freebsd-skq/sys/dev/ath/if_ath_tx.c

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/*-
* Copyright (c) 2002-2009 Sam Leffler, Errno Consulting
* Copyright (c) 2010-2012 Adrian Chadd, Xenion Pty Ltd
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
* redistribution must be conditioned upon including a substantially
* similar Disclaimer requirement for further binary redistribution.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
* OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
* IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGES.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Driver for the Atheros Wireless LAN controller.
*
* This software is derived from work of Atsushi Onoe; his contribution
* is greatly appreciated.
*/
#include "opt_inet.h"
#include "opt_ath.h"
#include "opt_wlan.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <sys/mbuf.h>
#include <sys/malloc.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/kernel.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/errno.h>
#include <sys/callout.h>
#include <sys/bus.h>
#include <sys/endian.h>
#include <sys/kthread.h>
#include <sys/taskqueue.h>
#include <sys/priv.h>
#include <sys/ktr.h>
#include <machine/bus.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_dl.h>
#include <net/if_media.h>
#include <net/if_types.h>
#include <net/if_arp.h>
#include <net/ethernet.h>
#include <net/if_llc.h>
#include <net80211/ieee80211_var.h>
#include <net80211/ieee80211_regdomain.h>
#ifdef IEEE80211_SUPPORT_SUPERG
#include <net80211/ieee80211_superg.h>
#endif
#ifdef IEEE80211_SUPPORT_TDMA
#include <net80211/ieee80211_tdma.h>
#endif
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
#include <net80211/ieee80211_ht.h>
#include <net/bpf.h>
#ifdef INET
#include <netinet/in.h>
#include <netinet/if_ether.h>
#endif
#include <dev/ath/if_athvar.h>
#include <dev/ath/ath_hal/ah_devid.h> /* XXX for softled */
#include <dev/ath/ath_hal/ah_diagcodes.h>
#include <dev/ath/if_ath_debug.h>
#ifdef ATH_TX99_DIAG
#include <dev/ath/ath_tx99/ath_tx99.h>
#endif
#include <dev/ath/if_ath_misc.h>
#include <dev/ath/if_ath_tx.h>
#include <dev/ath/if_ath_tx_ht.h>
#ifdef ATH_DEBUG_ALQ
#include <dev/ath/if_ath_alq.h>
#endif
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* How many retries to perform in software
*/
#define SWMAX_RETRIES 10
Map the non-QoS TID to the voice queue, in order to ensure important things like EAPOL frames make it out. After a whole bunch of hacking/testing, I discovered that they weren't being early-dropped by the stack (but I should look at ensuring that later..) but were even making to the hardware transmit queue. They were mostly even being received by the remote end. However, the remote end was completely ignoring them. This didn't happen under 150-170MBit TCP tests as I'm guessing the TX queue stayed very busy and the STA didn't do any scanning. However, when doing 100Mbit/s of TCP traffic, the STA would do background scanning - which involves it coming in and out of powersave mode with the AP. Now, this is a total and utter hack around the real problems, which are: * I need to implement proper power save handling and integrate it into the filtered frames support, so the driver/stack doesn't send frames whilst the station is actually in sleep; * .. but frames were actually making it to the STA (macbook pro) and the AP did receive an ACK; but a tcpdump on the receiving side showed the EAPOL frame never made it. So the stack was dropping it for some reason; * Importantly - the EAPOL frames are currently going into the non-QoS TID, which maps to the BE queue and is susceptible to that queue being busy doing other things, but; * There's other traffic going on in the non-QoS TID from other contexts when scanning is going on and it's possible there's some races causing sequence number/IV issues, but; * Importantly importantlly, I think the interaction with TID 16 multicast traffic in power save mode is causing issues - since I -believe- the sequence number space being used by the EAPOL frames on TID 16 overlaps with the multicast frames that have sequence numbers allocated and are then stuffed on the cabq. Since with EAPOL frames being in TID 16 and queued to the BE queue, it's going to be waiting to be serviced with all of the aggregate traffic going on - and if the CABQ gets emptied beforehand, those TID 16 multicast frames with sequence numbers will go out beforehand. Now, there's quite likely a bunch of "stuff happening slightly out of sequence" going on due to the nature of the TX path (read: lots of overlapping and concurrent ath_start() and ath_raw_xmit() calls going on, sigh) but I thought I had caught them all and stuffed each TID TX behind a lock (that lasted as long as it needed to in order to get the frame onto the relevant destination queue - thus keeping things in order.) Unfortunately the last problem is the big one and I'm going to stare at it some more. If it _is_ So this is a work around for now to ensure that EAPOL frames actually make it out before any other stuff in the non-QoS TID and HOPEFULLY before the CABQ gets active. I'm now going to spend a little time in the TX path figuring out exactly why the sender is rejecting things. There's two (well, three if you count EAPOL contents invalid) possibilities: * The sequence number is out of order (ie, something else like the multicast traffic on CABQ) is going out first on TID 16; * The CCMP IV is out of order (similar to above - but less likely, as the TX key for multicast traffic is different to unicast traffic); * EAPOL contents strangely invalid. AP: Ubiquiti RSPRO, AR9160/AR9220 NICs STA: Macbook Pro, Broadcom 11n NIC
2012-09-26 03:45:42 +00:00
/*
* What queue to throw the non-QoS TID traffic into
*/
#define ATH_NONQOS_TID_AC WME_AC_VO
#if 0
static int ath_tx_node_is_asleep(struct ath_softc *sc, struct ath_node *an);
#endif
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
static int ath_tx_ampdu_pending(struct ath_softc *sc, struct ath_node *an,
int tid);
static int ath_tx_ampdu_running(struct ath_softc *sc, struct ath_node *an,
int tid);
static ieee80211_seq ath_tx_tid_seqno_assign(struct ath_softc *sc,
struct ieee80211_node *ni, struct ath_buf *bf, struct mbuf *m0);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
static int ath_tx_action_frame_override_queue(struct ath_softc *sc,
struct ieee80211_node *ni, struct mbuf *m0, int *tid);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
static struct ath_buf *
ath_tx_retry_clone(struct ath_softc *sc, struct ath_node *an,
struct ath_tid *tid, struct ath_buf *bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
#ifdef ATH_DEBUG_ALQ
void
ath_tx_alq_post(struct ath_softc *sc, struct ath_buf *bf_first)
{
struct ath_buf *bf;
int i, n;
const char *ds;
/* XXX we should skip out early if debugging isn't enabled! */
bf = bf_first;
while (bf != NULL) {
/* XXX should ensure bf_nseg > 0! */
if (bf->bf_nseg == 0)
break;
n = ((bf->bf_nseg - 1) / sc->sc_tx_nmaps) + 1;
for (i = 0, ds = (const char *) bf->bf_desc;
i < n;
i++, ds += sc->sc_tx_desclen) {
if_ath_alq_post(&sc->sc_alq,
ATH_ALQ_EDMA_TXDESC,
sc->sc_tx_desclen,
ds);
}
bf = bf->bf_next;
}
}
#endif /* ATH_DEBUG_ALQ */
/*
* Whether to use the 11n rate scenario functions or not
*/
static inline int
ath_tx_is_11n(struct ath_softc *sc)
{
return ((sc->sc_ah->ah_magic == 0x20065416) ||
(sc->sc_ah->ah_magic == 0x19741014));
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Obtain the current TID from the given frame.
*
* Non-QoS frames need to go into TID 16 (IEEE80211_NONQOS_TID.)
* This has implications for which AC/priority the packet is placed
* in.
*/
static int
ath_tx_gettid(struct ath_softc *sc, const struct mbuf *m0)
{
const struct ieee80211_frame *wh;
int pri = M_WME_GETAC(m0);
wh = mtod(m0, const struct ieee80211_frame *);
if (! IEEE80211_QOS_HAS_SEQ(wh))
return IEEE80211_NONQOS_TID;
else
return WME_AC_TO_TID(pri);
}
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
static void
ath_tx_set_retry(struct ath_softc *sc, struct ath_buf *bf)
{
struct ieee80211_frame *wh;
wh = mtod(bf->bf_m, struct ieee80211_frame *);
/* Only update/resync if needed */
if (bf->bf_state.bfs_isretried == 0) {
wh->i_fc[1] |= IEEE80211_FC1_RETRY;
bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap,
BUS_DMASYNC_PREWRITE);
}
bf->bf_state.bfs_isretried = 1;
bf->bf_state.bfs_retries ++;
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Determine what the correct AC queue for the given frame
* should be.
*
* This code assumes that the TIDs map consistently to
* the underlying hardware (or software) ath_txq.
* Since the sender may try to set an AC which is
* arbitrary, non-QoS TIDs may end up being put on
* completely different ACs. There's no way to put a
* TID into multiple ath_txq's for scheduling, so
* for now we override the AC/TXQ selection and set
* non-QOS TID frames into the BE queue.
*
* This may be completely incorrect - specifically,
* some management frames may end up out of order
* compared to the QoS traffic they're controlling.
* I'll look into this later.
*/
static int
ath_tx_getac(struct ath_softc *sc, const struct mbuf *m0)
{
const struct ieee80211_frame *wh;
int pri = M_WME_GETAC(m0);
wh = mtod(m0, const struct ieee80211_frame *);
if (IEEE80211_QOS_HAS_SEQ(wh))
return pri;
Map the non-QoS TID to the voice queue, in order to ensure important things like EAPOL frames make it out. After a whole bunch of hacking/testing, I discovered that they weren't being early-dropped by the stack (but I should look at ensuring that later..) but were even making to the hardware transmit queue. They were mostly even being received by the remote end. However, the remote end was completely ignoring them. This didn't happen under 150-170MBit TCP tests as I'm guessing the TX queue stayed very busy and the STA didn't do any scanning. However, when doing 100Mbit/s of TCP traffic, the STA would do background scanning - which involves it coming in and out of powersave mode with the AP. Now, this is a total and utter hack around the real problems, which are: * I need to implement proper power save handling and integrate it into the filtered frames support, so the driver/stack doesn't send frames whilst the station is actually in sleep; * .. but frames were actually making it to the STA (macbook pro) and the AP did receive an ACK; but a tcpdump on the receiving side showed the EAPOL frame never made it. So the stack was dropping it for some reason; * Importantly - the EAPOL frames are currently going into the non-QoS TID, which maps to the BE queue and is susceptible to that queue being busy doing other things, but; * There's other traffic going on in the non-QoS TID from other contexts when scanning is going on and it's possible there's some races causing sequence number/IV issues, but; * Importantly importantlly, I think the interaction with TID 16 multicast traffic in power save mode is causing issues - since I -believe- the sequence number space being used by the EAPOL frames on TID 16 overlaps with the multicast frames that have sequence numbers allocated and are then stuffed on the cabq. Since with EAPOL frames being in TID 16 and queued to the BE queue, it's going to be waiting to be serviced with all of the aggregate traffic going on - and if the CABQ gets emptied beforehand, those TID 16 multicast frames with sequence numbers will go out beforehand. Now, there's quite likely a bunch of "stuff happening slightly out of sequence" going on due to the nature of the TX path (read: lots of overlapping and concurrent ath_start() and ath_raw_xmit() calls going on, sigh) but I thought I had caught them all and stuffed each TID TX behind a lock (that lasted as long as it needed to in order to get the frame onto the relevant destination queue - thus keeping things in order.) Unfortunately the last problem is the big one and I'm going to stare at it some more. If it _is_ So this is a work around for now to ensure that EAPOL frames actually make it out before any other stuff in the non-QoS TID and HOPEFULLY before the CABQ gets active. I'm now going to spend a little time in the TX path figuring out exactly why the sender is rejecting things. There's two (well, three if you count EAPOL contents invalid) possibilities: * The sequence number is out of order (ie, something else like the multicast traffic on CABQ) is going out first on TID 16; * The CCMP IV is out of order (similar to above - but less likely, as the TX key for multicast traffic is different to unicast traffic); * EAPOL contents strangely invalid. AP: Ubiquiti RSPRO, AR9160/AR9220 NICs STA: Macbook Pro, Broadcom 11n NIC
2012-09-26 03:45:42 +00:00
return ATH_NONQOS_TID_AC;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
void
ath_txfrag_cleanup(struct ath_softc *sc,
ath_bufhead *frags, struct ieee80211_node *ni)
{
struct ath_buf *bf, *next;
ATH_TXBUF_LOCK_ASSERT(sc);
TAILQ_FOREACH_SAFE(bf, frags, bf_list, next) {
/* NB: bf assumed clean */
TAILQ_REMOVE(frags, bf, bf_list);
ath_returnbuf_head(sc, bf);
ieee80211_node_decref(ni);
}
}
/*
* Setup xmit of a fragmented frame. Allocate a buffer
* for each frag and bump the node reference count to
* reflect the held reference to be setup by ath_tx_start.
*/
int
ath_txfrag_setup(struct ath_softc *sc, ath_bufhead *frags,
struct mbuf *m0, struct ieee80211_node *ni)
{
struct mbuf *m;
struct ath_buf *bf;
ATH_TXBUF_LOCK(sc);
for (m = m0->m_nextpkt; m != NULL; m = m->m_nextpkt) {
/* XXX non-management? */
bf = _ath_getbuf_locked(sc, ATH_BUFTYPE_NORMAL);
if (bf == NULL) { /* out of buffers, cleanup */
DPRINTF(sc, ATH_DEBUG_XMIT, "%s: no buffer?\n",
__func__);
ath_txfrag_cleanup(sc, frags, ni);
break;
}
ieee80211_node_incref(ni);
TAILQ_INSERT_TAIL(frags, bf, bf_list);
}
ATH_TXBUF_UNLOCK(sc);
return !TAILQ_EMPTY(frags);
}
/*
* Reclaim mbuf resources. For fragmented frames we
* need to claim each frag chained with m_nextpkt.
*/
void
ath_freetx(struct mbuf *m)
{
struct mbuf *next;
do {
next = m->m_nextpkt;
m->m_nextpkt = NULL;
m_freem(m);
} while ((m = next) != NULL);
}
static int
ath_tx_dmasetup(struct ath_softc *sc, struct ath_buf *bf, struct mbuf *m0)
{
struct mbuf *m;
int error;
/*
* Load the DMA map so any coalescing is done. This
* also calculates the number of descriptors we need.
*/
error = bus_dmamap_load_mbuf_sg(sc->sc_dmat, bf->bf_dmamap, m0,
bf->bf_segs, &bf->bf_nseg,
BUS_DMA_NOWAIT);
if (error == EFBIG) {
/* XXX packet requires too many descriptors */
bf->bf_nseg = ATH_MAX_SCATTER + 1;
} else if (error != 0) {
sc->sc_stats.ast_tx_busdma++;
ath_freetx(m0);
return error;
}
/*
* Discard null packets and check for packets that
* require too many TX descriptors. We try to convert
* the latter to a cluster.
*/
if (bf->bf_nseg > ATH_MAX_SCATTER) { /* too many desc's, linearize */
sc->sc_stats.ast_tx_linear++;
m = m_collapse(m0, M_NOWAIT, ATH_MAX_SCATTER);
if (m == NULL) {
ath_freetx(m0);
sc->sc_stats.ast_tx_nombuf++;
return ENOMEM;
}
m0 = m;
error = bus_dmamap_load_mbuf_sg(sc->sc_dmat, bf->bf_dmamap, m0,
bf->bf_segs, &bf->bf_nseg,
BUS_DMA_NOWAIT);
if (error != 0) {
sc->sc_stats.ast_tx_busdma++;
ath_freetx(m0);
return error;
}
KASSERT(bf->bf_nseg <= ATH_MAX_SCATTER,
("too many segments after defrag; nseg %u", bf->bf_nseg));
} else if (bf->bf_nseg == 0) { /* null packet, discard */
sc->sc_stats.ast_tx_nodata++;
ath_freetx(m0);
return EIO;
}
DPRINTF(sc, ATH_DEBUG_XMIT, "%s: m %p len %u\n",
__func__, m0, m0->m_pkthdr.len);
bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_PREWRITE);
bf->bf_m = m0;
return 0;
}
/*
Convert the aggregate descriptor path over to use the same API as the non-aggregate path. I "cheated" by using some TX setup code in our HAL that isn't present in the atheros HAL (or Linux ath9k.) The old path for forming aggregates was: * setup the rate control in the first descriptor; * call chaintxdesc() on all the frames; * call setupfirsttxdesc() on the first descrpitor in the first frame; * call setuplasttxdesc() on the last descriptor in the last frame. The new path for forming aggregates looks like the non-aggregate path: * call setuptxdesc() on the first descriptor in the first frame; * setup the rate control in the first descriptor; * call filltxdesc() on each descriptor in the frame; * if it's an aggregate - call set11n_aggr_{first, middle, last} as appropriate (see the code for a description of what is "appropriate".) Now, this is done primarily for the AR9300 HAL - it doesn't implement the first set of aggregate functions. It just has the older methods and the "first/middle/last" aggregate methods. So, let's convert the code to use these. Note: the AR5416 HAL in FreeBSD had that code (from me, a while ago) and a previous commit brought it up to behave the same as the AR9300 HAL routines. There's some further tidyups to be done - specifically, avoid doing multiple calls to the 11n descriptor functions. I shouldn't call clr11n_aggr(), then set11n_aggr_middle(), then also set11n_aggr_first(). On (at least MIPS) the TX descriptors are in non-cachable memory and this will cause multiple slow writes. I'll debug/tidy that up in a future commit. Tested: * AR9280, STA * AR9280/AR9160, AP * AR9380, STA (using a local, closed source HAL, sorry!)
2012-11-06 06:19:11 +00:00
* Chain together segments+descriptors for a frame - 11n or otherwise.
*
* For aggregates, this is called on each frame in the aggregate.
*/
static void
Convert the aggregate descriptor path over to use the same API as the non-aggregate path. I "cheated" by using some TX setup code in our HAL that isn't present in the atheros HAL (or Linux ath9k.) The old path for forming aggregates was: * setup the rate control in the first descriptor; * call chaintxdesc() on all the frames; * call setupfirsttxdesc() on the first descrpitor in the first frame; * call setuplasttxdesc() on the last descriptor in the last frame. The new path for forming aggregates looks like the non-aggregate path: * call setuptxdesc() on the first descriptor in the first frame; * setup the rate control in the first descriptor; * call filltxdesc() on each descriptor in the frame; * if it's an aggregate - call set11n_aggr_{first, middle, last} as appropriate (see the code for a description of what is "appropriate".) Now, this is done primarily for the AR9300 HAL - it doesn't implement the first set of aggregate functions. It just has the older methods and the "first/middle/last" aggregate methods. So, let's convert the code to use these. Note: the AR5416 HAL in FreeBSD had that code (from me, a while ago) and a previous commit brought it up to behave the same as the AR9300 HAL routines. There's some further tidyups to be done - specifically, avoid doing multiple calls to the 11n descriptor functions. I shouldn't call clr11n_aggr(), then set11n_aggr_middle(), then also set11n_aggr_first(). On (at least MIPS) the TX descriptors are in non-cachable memory and this will cause multiple slow writes. I'll debug/tidy that up in a future commit. Tested: * AR9280, STA * AR9280/AR9160, AP * AR9380, STA (using a local, closed source HAL, sorry!)
2012-11-06 06:19:11 +00:00
ath_tx_chaindesclist(struct ath_softc *sc, struct ath_desc *ds0,
struct ath_buf *bf, int is_aggr, int is_first_subframe,
int is_last_subframe)
{
struct ath_hal *ah = sc->sc_ah;
Convert the aggregate descriptor path over to use the same API as the non-aggregate path. I "cheated" by using some TX setup code in our HAL that isn't present in the atheros HAL (or Linux ath9k.) The old path for forming aggregates was: * setup the rate control in the first descriptor; * call chaintxdesc() on all the frames; * call setupfirsttxdesc() on the first descrpitor in the first frame; * call setuplasttxdesc() on the last descriptor in the last frame. The new path for forming aggregates looks like the non-aggregate path: * call setuptxdesc() on the first descriptor in the first frame; * setup the rate control in the first descriptor; * call filltxdesc() on each descriptor in the frame; * if it's an aggregate - call set11n_aggr_{first, middle, last} as appropriate (see the code for a description of what is "appropriate".) Now, this is done primarily for the AR9300 HAL - it doesn't implement the first set of aggregate functions. It just has the older methods and the "first/middle/last" aggregate methods. So, let's convert the code to use these. Note: the AR5416 HAL in FreeBSD had that code (from me, a while ago) and a previous commit brought it up to behave the same as the AR9300 HAL routines. There's some further tidyups to be done - specifically, avoid doing multiple calls to the 11n descriptor functions. I shouldn't call clr11n_aggr(), then set11n_aggr_middle(), then also set11n_aggr_first(). On (at least MIPS) the TX descriptors are in non-cachable memory and this will cause multiple slow writes. I'll debug/tidy that up in a future commit. Tested: * AR9280, STA * AR9280/AR9160, AP * AR9380, STA (using a local, closed source HAL, sorry!)
2012-11-06 06:19:11 +00:00
char *ds;
int i, bp, dsp;
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
HAL_DMA_ADDR bufAddrList[4];
uint32_t segLenList[4];
int numTxMaps = 1;
int isFirstDesc = 1;
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
/*
* XXX There's txdma and txdma_mgmt; the descriptor
* sizes must match.
*/
struct ath_descdma *dd = &sc->sc_txdma;
/*
* Fillin the remainder of the descriptor info.
*/
/*
* We need the number of TX data pointers in each descriptor.
* EDMA and later chips support 4 TX buffers per descriptor;
* previous chips just support one.
*/
numTxMaps = sc->sc_tx_nmaps;
/*
* For EDMA and later chips ensure the TX map is fully populated
* before advancing to the next descriptor.
*/
Convert the aggregate descriptor path over to use the same API as the non-aggregate path. I "cheated" by using some TX setup code in our HAL that isn't present in the atheros HAL (or Linux ath9k.) The old path for forming aggregates was: * setup the rate control in the first descriptor; * call chaintxdesc() on all the frames; * call setupfirsttxdesc() on the first descrpitor in the first frame; * call setuplasttxdesc() on the last descriptor in the last frame. The new path for forming aggregates looks like the non-aggregate path: * call setuptxdesc() on the first descriptor in the first frame; * setup the rate control in the first descriptor; * call filltxdesc() on each descriptor in the frame; * if it's an aggregate - call set11n_aggr_{first, middle, last} as appropriate (see the code for a description of what is "appropriate".) Now, this is done primarily for the AR9300 HAL - it doesn't implement the first set of aggregate functions. It just has the older methods and the "first/middle/last" aggregate methods. So, let's convert the code to use these. Note: the AR5416 HAL in FreeBSD had that code (from me, a while ago) and a previous commit brought it up to behave the same as the AR9300 HAL routines. There's some further tidyups to be done - specifically, avoid doing multiple calls to the 11n descriptor functions. I shouldn't call clr11n_aggr(), then set11n_aggr_middle(), then also set11n_aggr_first(). On (at least MIPS) the TX descriptors are in non-cachable memory and this will cause multiple slow writes. I'll debug/tidy that up in a future commit. Tested: * AR9280, STA * AR9280/AR9160, AP * AR9380, STA (using a local, closed source HAL, sorry!)
2012-11-06 06:19:11 +00:00
ds = (char *) bf->bf_desc;
bp = dsp = 0;
bzero(bufAddrList, sizeof(bufAddrList));
bzero(segLenList, sizeof(segLenList));
for (i = 0; i < bf->bf_nseg; i++) {
bufAddrList[bp] = bf->bf_segs[i].ds_addr;
segLenList[bp] = bf->bf_segs[i].ds_len;
bp++;
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
/*
* Go to the next segment if this isn't the last segment
* and there's space in the current TX map.
*/
if ((i != bf->bf_nseg - 1) && (bp < numTxMaps))
continue;
/*
* Last segment or we're out of buffer pointers.
*/
bp = 0;
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
if (i == bf->bf_nseg - 1)
ath_hal_settxdesclink(ah, (struct ath_desc *) ds, 0);
else
ath_hal_settxdesclink(ah, (struct ath_desc *) ds,
bf->bf_daddr + dd->dd_descsize * (dsp + 1));
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
/*
* XXX This assumes that bfs_txq is the actual destination
* hardware queue at this point. It may not have been
* assigned, it may actually be pointing to the multicast
* software TXQ id. These must be fixed!
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
*/
ath_hal_filltxdesc(ah, (struct ath_desc *) ds
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
, bufAddrList
, segLenList
, bf->bf_descid /* XXX desc id */
, bf->bf_state.bfs_tx_queue
, isFirstDesc /* first segment */
, i == bf->bf_nseg - 1 /* last segment */
, (struct ath_desc *) ds0 /* first descriptor */
);
Convert the aggregate descriptor path over to use the same API as the non-aggregate path. I "cheated" by using some TX setup code in our HAL that isn't present in the atheros HAL (or Linux ath9k.) The old path for forming aggregates was: * setup the rate control in the first descriptor; * call chaintxdesc() on all the frames; * call setupfirsttxdesc() on the first descrpitor in the first frame; * call setuplasttxdesc() on the last descriptor in the last frame. The new path for forming aggregates looks like the non-aggregate path: * call setuptxdesc() on the first descriptor in the first frame; * setup the rate control in the first descriptor; * call filltxdesc() on each descriptor in the frame; * if it's an aggregate - call set11n_aggr_{first, middle, last} as appropriate (see the code for a description of what is "appropriate".) Now, this is done primarily for the AR9300 HAL - it doesn't implement the first set of aggregate functions. It just has the older methods and the "first/middle/last" aggregate methods. So, let's convert the code to use these. Note: the AR5416 HAL in FreeBSD had that code (from me, a while ago) and a previous commit brought it up to behave the same as the AR9300 HAL routines. There's some further tidyups to be done - specifically, avoid doing multiple calls to the 11n descriptor functions. I shouldn't call clr11n_aggr(), then set11n_aggr_middle(), then also set11n_aggr_first(). On (at least MIPS) the TX descriptors are in non-cachable memory and this will cause multiple slow writes. I'll debug/tidy that up in a future commit. Tested: * AR9280, STA * AR9280/AR9160, AP * AR9380, STA (using a local, closed source HAL, sorry!)
2012-11-06 06:19:11 +00:00
/*
* Make sure the 11n aggregate fields are cleared.
*
* XXX TODO: this doesn't need to be called for
* aggregate frames; as it'll be called on all
* sub-frames. Since the descriptors are in
* non-cacheable memory, this leads to some
* rather slow writes on MIPS/ARM platforms.
*/
if (ath_tx_is_11n(sc))
ath_hal_clr11n_aggr(sc->sc_ah, (struct ath_desc *) ds);
Convert the aggregate descriptor path over to use the same API as the non-aggregate path. I "cheated" by using some TX setup code in our HAL that isn't present in the atheros HAL (or Linux ath9k.) The old path for forming aggregates was: * setup the rate control in the first descriptor; * call chaintxdesc() on all the frames; * call setupfirsttxdesc() on the first descrpitor in the first frame; * call setuplasttxdesc() on the last descriptor in the last frame. The new path for forming aggregates looks like the non-aggregate path: * call setuptxdesc() on the first descriptor in the first frame; * setup the rate control in the first descriptor; * call filltxdesc() on each descriptor in the frame; * if it's an aggregate - call set11n_aggr_{first, middle, last} as appropriate (see the code for a description of what is "appropriate".) Now, this is done primarily for the AR9300 HAL - it doesn't implement the first set of aggregate functions. It just has the older methods and the "first/middle/last" aggregate methods. So, let's convert the code to use these. Note: the AR5416 HAL in FreeBSD had that code (from me, a while ago) and a previous commit brought it up to behave the same as the AR9300 HAL routines. There's some further tidyups to be done - specifically, avoid doing multiple calls to the 11n descriptor functions. I shouldn't call clr11n_aggr(), then set11n_aggr_middle(), then also set11n_aggr_first(). On (at least MIPS) the TX descriptors are in non-cachable memory and this will cause multiple slow writes. I'll debug/tidy that up in a future commit. Tested: * AR9280, STA * AR9280/AR9160, AP * AR9380, STA (using a local, closed source HAL, sorry!)
2012-11-06 06:19:11 +00:00
/*
* If 11n is enabled, set it up as if it's an aggregate
* frame.
*/
if (is_last_subframe) {
ath_hal_set11n_aggr_last(sc->sc_ah,
(struct ath_desc *) ds);
} else if (is_aggr) {
/*
* This clears the aggrlen field; so
* the caller needs to call set_aggr_first()!
*
* XXX TODO: don't call this for the first
* descriptor in the first frame in an
* aggregate!
*/
ath_hal_set11n_aggr_middle(sc->sc_ah,
(struct ath_desc *) ds,
bf->bf_state.bfs_ndelim);
}
isFirstDesc = 0;
bf->bf_lastds = (struct ath_desc *) ds;
/*
* Don't forget to skip to the next descriptor.
*/
ds += sc->sc_tx_desclen;
dsp++;
/*
* .. and don't forget to blank these out!
*/
bzero(bufAddrList, sizeof(bufAddrList));
bzero(segLenList, sizeof(segLenList));
}
bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_PREWRITE);
}
/*
* Set the rate control fields in the given descriptor based on
* the bf_state fields and node state.
*
* The bfs fields should already be set with the relevant rate
* control information, including whether MRR is to be enabled.
*
* Since the FreeBSD HAL currently sets up the first TX rate
* in ath_hal_setuptxdesc(), this will setup the MRR
* conditionally for the pre-11n chips, and call ath_buf_set_rate
* unconditionally for 11n chips. These require the 11n rate
* scenario to be set if MCS rates are enabled, so it's easier
* to just always call it. The caller can then only set rates 2, 3
* and 4 if multi-rate retry is needed.
*/
static void
ath_tx_set_ratectrl(struct ath_softc *sc, struct ieee80211_node *ni,
struct ath_buf *bf)
{
struct ath_rc_series *rc = bf->bf_state.bfs_rc;
/* If mrr is disabled, blank tries 1, 2, 3 */
if (! bf->bf_state.bfs_ismrr)
rc[1].tries = rc[2].tries = rc[3].tries = 0;
#if 0
/*
* If NOACK is set, just set ntries=1.
*/
else if (bf->bf_state.bfs_txflags & HAL_TXDESC_NOACK) {
rc[1].tries = rc[2].tries = rc[3].tries = 0;
rc[0].tries = 1;
}
#endif
/*
* Always call - that way a retried descriptor will
* have the MRR fields overwritten.
*
* XXX TODO: see if this is really needed - setting up
* the first descriptor should set the MRR fields to 0
* for us anyway.
*/
if (ath_tx_is_11n(sc)) {
ath_buf_set_rate(sc, ni, bf);
} else {
ath_hal_setupxtxdesc(sc->sc_ah, bf->bf_desc
, rc[1].ratecode, rc[1].tries
, rc[2].ratecode, rc[2].tries
, rc[3].ratecode, rc[3].tries
);
}
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Setup segments+descriptors for an 11n aggregate.
* bf_first is the first buffer in the aggregate.
* The descriptor list must already been linked together using
* bf->bf_next.
*/
static void
ath_tx_setds_11n(struct ath_softc *sc, struct ath_buf *bf_first)
{
struct ath_buf *bf, *bf_prev = NULL;
Convert the aggregate descriptor path over to use the same API as the non-aggregate path. I "cheated" by using some TX setup code in our HAL that isn't present in the atheros HAL (or Linux ath9k.) The old path for forming aggregates was: * setup the rate control in the first descriptor; * call chaintxdesc() on all the frames; * call setupfirsttxdesc() on the first descrpitor in the first frame; * call setuplasttxdesc() on the last descriptor in the last frame. The new path for forming aggregates looks like the non-aggregate path: * call setuptxdesc() on the first descriptor in the first frame; * setup the rate control in the first descriptor; * call filltxdesc() on each descriptor in the frame; * if it's an aggregate - call set11n_aggr_{first, middle, last} as appropriate (see the code for a description of what is "appropriate".) Now, this is done primarily for the AR9300 HAL - it doesn't implement the first set of aggregate functions. It just has the older methods and the "first/middle/last" aggregate methods. So, let's convert the code to use these. Note: the AR5416 HAL in FreeBSD had that code (from me, a while ago) and a previous commit brought it up to behave the same as the AR9300 HAL routines. There's some further tidyups to be done - specifically, avoid doing multiple calls to the 11n descriptor functions. I shouldn't call clr11n_aggr(), then set11n_aggr_middle(), then also set11n_aggr_first(). On (at least MIPS) the TX descriptors are in non-cachable memory and this will cause multiple slow writes. I'll debug/tidy that up in a future commit. Tested: * AR9280, STA * AR9280/AR9160, AP * AR9380, STA (using a local, closed source HAL, sorry!)
2012-11-06 06:19:11 +00:00
struct ath_desc *ds0 = bf_first->bf_desc;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR, "%s: nframes=%d, al=%d\n",
__func__, bf_first->bf_state.bfs_nframes,
bf_first->bf_state.bfs_al);
bf = bf_first;
if (bf->bf_state.bfs_txrate0 == 0)
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR, "%s: bf=%p, txrate0=%d\n",
__func__, bf, 0);
if (bf->bf_state.bfs_rc[0].ratecode == 0)
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR, "%s: bf=%p, rix0=%d\n",
__func__, bf, 0);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
Convert the aggregate descriptor path over to use the same API as the non-aggregate path. I "cheated" by using some TX setup code in our HAL that isn't present in the atheros HAL (or Linux ath9k.) The old path for forming aggregates was: * setup the rate control in the first descriptor; * call chaintxdesc() on all the frames; * call setupfirsttxdesc() on the first descrpitor in the first frame; * call setuplasttxdesc() on the last descriptor in the last frame. The new path for forming aggregates looks like the non-aggregate path: * call setuptxdesc() on the first descriptor in the first frame; * setup the rate control in the first descriptor; * call filltxdesc() on each descriptor in the frame; * if it's an aggregate - call set11n_aggr_{first, middle, last} as appropriate (see the code for a description of what is "appropriate".) Now, this is done primarily for the AR9300 HAL - it doesn't implement the first set of aggregate functions. It just has the older methods and the "first/middle/last" aggregate methods. So, let's convert the code to use these. Note: the AR5416 HAL in FreeBSD had that code (from me, a while ago) and a previous commit brought it up to behave the same as the AR9300 HAL routines. There's some further tidyups to be done - specifically, avoid doing multiple calls to the 11n descriptor functions. I shouldn't call clr11n_aggr(), then set11n_aggr_middle(), then also set11n_aggr_first(). On (at least MIPS) the TX descriptors are in non-cachable memory and this will cause multiple slow writes. I'll debug/tidy that up in a future commit. Tested: * AR9280, STA * AR9280/AR9160, AP * AR9380, STA (using a local, closed source HAL, sorry!)
2012-11-06 06:19:11 +00:00
* Setup all descriptors of all subframes - this will
* call ath_hal_set11naggrmiddle() on every frame.
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
*/
while (bf != NULL) {
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
"%s: bf=%p, nseg=%d, pktlen=%d, seqno=%d\n",
__func__, bf, bf->bf_nseg, bf->bf_state.bfs_pktlen,
SEQNO(bf->bf_state.bfs_seqno));
Convert the aggregate descriptor path over to use the same API as the non-aggregate path. I "cheated" by using some TX setup code in our HAL that isn't present in the atheros HAL (or Linux ath9k.) The old path for forming aggregates was: * setup the rate control in the first descriptor; * call chaintxdesc() on all the frames; * call setupfirsttxdesc() on the first descrpitor in the first frame; * call setuplasttxdesc() on the last descriptor in the last frame. The new path for forming aggregates looks like the non-aggregate path: * call setuptxdesc() on the first descriptor in the first frame; * setup the rate control in the first descriptor; * call filltxdesc() on each descriptor in the frame; * if it's an aggregate - call set11n_aggr_{first, middle, last} as appropriate (see the code for a description of what is "appropriate".) Now, this is done primarily for the AR9300 HAL - it doesn't implement the first set of aggregate functions. It just has the older methods and the "first/middle/last" aggregate methods. So, let's convert the code to use these. Note: the AR5416 HAL in FreeBSD had that code (from me, a while ago) and a previous commit brought it up to behave the same as the AR9300 HAL routines. There's some further tidyups to be done - specifically, avoid doing multiple calls to the 11n descriptor functions. I shouldn't call clr11n_aggr(), then set11n_aggr_middle(), then also set11n_aggr_first(). On (at least MIPS) the TX descriptors are in non-cachable memory and this will cause multiple slow writes. I'll debug/tidy that up in a future commit. Tested: * AR9280, STA * AR9280/AR9160, AP * AR9380, STA (using a local, closed source HAL, sorry!)
2012-11-06 06:19:11 +00:00
/*
* Setup the initial fields for the first descriptor - all
* the non-11n specific stuff.
*/
ath_hal_setuptxdesc(sc->sc_ah, bf->bf_desc
, bf->bf_state.bfs_pktlen /* packet length */
, bf->bf_state.bfs_hdrlen /* header length */
, bf->bf_state.bfs_atype /* Atheros packet type */
, bf->bf_state.bfs_txpower /* txpower */
, bf->bf_state.bfs_txrate0
, bf->bf_state.bfs_try0 /* series 0 rate/tries */
, bf->bf_state.bfs_keyix /* key cache index */
, bf->bf_state.bfs_txantenna /* antenna mode */
, bf->bf_state.bfs_txflags | HAL_TXDESC_INTREQ /* flags */
, bf->bf_state.bfs_ctsrate /* rts/cts rate */
, bf->bf_state.bfs_ctsduration /* rts/cts duration */
);
/*
* First descriptor? Setup the rate control and initial
* aggregate header information.
*/
if (bf == bf_first) {
/*
* setup first desc with rate and aggr info
*/
ath_tx_set_ratectrl(sc, bf->bf_node, bf);
}
/*
* Setup the descriptors for a multi-descriptor frame.
* This is both aggregate and non-aggregate aware.
*/
ath_tx_chaindesclist(sc, ds0, bf,
1, /* is_aggr */
!! (bf == bf_first), /* is_first_subframe */
!! (bf->bf_next == NULL) /* is_last_subframe */
);
if (bf == bf_first) {
/*
* Initialise the first 11n aggregate with the
* aggregate length and aggregate enable bits.
*/
ath_hal_set11n_aggr_first(sc->sc_ah,
ds0,
bf->bf_state.bfs_al,
bf->bf_state.bfs_ndelim);
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Link the last descriptor of the previous frame
* to the beginning descriptor of this frame.
*/
if (bf_prev != NULL)
Convert the TX path to use the new HAL methods for accessing the TX descriptor link pointers. This is required for the AR93xx and later chipsets. The RX path is slightly different - the legacy RX path directly accesses ath_desc->ds_link for now, however this isn't at all done for EDMA (FIFO) RX. Now, for those performing a little software archeology here: This is all a bit sub-optimal. "struct ath_desc" is only really relevant for the pre-AR93xx NICs - where ds_link and ds_data is always in the same location. The AR93xx and later NICs have different descriptor layouts altogether. Now, for AR93xx and later NICs, you should never directly reference ds_link and ds_data, as: * the RX descriptors don't have either - the data is _after_ the RX descriptor. They're just one large buffer. There's also no need for a per-descriptor RX buffer size as they're all fixed sizes. * the TX descriptors have 4 buffer and 4 length fields _and_ a link pointer. Each frame takes up one TX FIFO pointer, but it can contain multiple subframes (either multiple frames in a buffer, and/or multiple frames in an aggregate/RIFS burst.) * .. so, when TX frames are queued to a hardware queue, the link pointer is ONLY for buffers in that frame/aggregate. The next frame starts in a new FIFO pointer. * Finally, descriptor completion status is in a different ring. I'll write something up about that when its time to do so. This was inspired by Linux ath9k and the reference driver but is a reimplementation. Obtained from: Linux ath9k, Qualcomm Atheros
2012-07-19 03:51:16 +00:00
ath_hal_settxdesclink(sc->sc_ah, bf_prev->bf_lastds,
bf->bf_daddr);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Save a copy so we can link the next descriptor in */
bf_prev = bf;
bf = bf->bf_next;
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Set the first descriptor bf_lastds field to point to
* the last descriptor in the last subframe, that's where
* the status update will occur.
*/
bf_first->bf_lastds = bf_prev->bf_lastds;
/*
* And bf_last in the first descriptor points to the end of
* the aggregate list.
*/
bf_first->bf_last = bf_prev;
/*
* For non-AR9300 NICs, which require the rate control
* in the final descriptor - let's set that up now.
*
* This is because the filltxdesc() HAL call doesn't
* populate the last segment with rate control information
* if firstSeg is also true. For non-aggregate frames
* that is fine, as the first frame already has rate control
* info. But if the last frame in an aggregate has one
* descriptor, both firstseg and lastseg will be true and
* the rate info isn't copied.
*
* This is inefficient on MIPS/ARM platforms that have
* non-cachable memory for TX descriptors, but we'll just
* make do for now.
*
* As to why the rate table is stashed in the last descriptor
* rather than the first descriptor? Because proctxdesc()
* is called on the final descriptor in an MPDU or A-MPDU -
* ie, the one that gets updated by the hardware upon
* completion. That way proctxdesc() doesn't need to know
* about the first _and_ last TX descriptor.
*/
ath_hal_setuplasttxdesc(sc->sc_ah, bf_prev->bf_lastds, ds0);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR, "%s: end\n", __func__);
}
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
/*
* Hand-off a frame to the multicast TX queue.
*
* This is a software TXQ which will be appended to the CAB queue
* during the beacon setup code.
*
* XXX TODO: since the AR9300 EDMA TX queue support wants the QCU ID
* as part of the TX descriptor, bf_state.bfs_tx_queue must be updated
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
* with the actual hardware txq, or all of this will fall apart.
*
* XXX It may not be a bad idea to just stuff the QCU ID into bf_state
* and retire bfs_tx_queue; then make sure the CABQ QCU ID is populated
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
* correctly.
*/
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
static void
ath_tx_handoff_mcast(struct ath_softc *sc, struct ath_txq *txq,
struct ath_buf *bf)
{
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
KASSERT((bf->bf_flags & ATH_BUF_BUSY) == 0,
("%s: busy status 0x%x", __func__, bf->bf_flags));
/*
* Ensure that the tx queue is the cabq, so things get
* mapped correctly.
*/
if (bf->bf_state.bfs_tx_queue != sc->sc_cabq->axq_qnum) {
DPRINTF(sc, ATH_DEBUG_XMIT,
"%s: bf=%p, bfs_tx_queue=%d, axq_qnum=%d\n",
__func__, bf, bf->bf_state.bfs_tx_queue,
txq->axq_qnum);
}
ATH_TXQ_LOCK(txq);
if (ATH_TXQ_LAST(txq, axq_q_s) != NULL) {
struct ath_buf *bf_last = ATH_TXQ_LAST(txq, axq_q_s);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
struct ieee80211_frame *wh;
/* mark previous frame */
wh = mtod(bf_last->bf_m, struct ieee80211_frame *);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
wh->i_fc[1] |= IEEE80211_FC1_MORE_DATA;
bus_dmamap_sync(sc->sc_dmat, bf_last->bf_dmamap,
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
BUS_DMASYNC_PREWRITE);
/* link descriptor */
ath_hal_settxdesclink(sc->sc_ah,
bf_last->bf_lastds,
bf->bf_daddr);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
ATH_TXQ_INSERT_TAIL(txq, bf, bf_list);
Overhaul the TXQ locking (again!) as part of some beacon/cabq timing related issues. Moving the TX locking under one lock made things easier to progress on but it had one important side-effect - it increased the latency when handling CABQ setup when sending beacons. This commit introduces a bunch of new changes and a few unrelated changs that are just easier to lump in here. The aim is to have the CABQ locking separate from other locking. The CABQ transmit path in the beacon process thus doesn't have to grab the general TX lock, reducing lock contention/latency and making it more likely that we'll make the beacon TX timing. The second half of this commit is the CABQ related setup changes needed for sane looking EDMA CABQ support. Right now the EDMA TX code naively assumes that only one frame (MPDU or A-MPDU) is being pushed into each FIFO slot. For the CABQ this isn't true - a whole list of frames is being pushed in - and thus CABQ handling breaks very quickly. The aim here is to setup the CABQ list and then push _that list_ to the hardware for transmission. I can then extend the EDMA TX code to stamp that list as being "one" FIFO entry (likely by tagging the last buffer in that list as "FIFO END") so the EDMA TX completion code correctly tracks things. Major: * Migrate the per-TXQ add/removal locking back to per-TXQ, rather than a single lock. * Leave the software queue side of things under the ATH_TX_LOCK lock, (continuing) to serialise things as they are. * Add a new function which is called whenever there's a beacon miss, to print out some debugging. This is primarily designed to help me figure out if the beacon miss events are due to a noisy environment, issues with the PHY/MAC, or other. * Move the CABQ setup/enable to occur _after_ all the VAPs have been looked at. This means that for multiple VAPS in bursted mode, the CABQ gets primed once all VAPs are checked, rather than being primed on the first VAP and then having frames appended after this. Minor: * Add a (disabled) twiddle to let me enable/disable cabq traffic. It's primarily there to let me easily debug what's going on with beacon and CABQ setup/traffic; there's some DMA engine hangs which I'm finally trying to trace down. * Clear bf_next when flushing frames; it should quieten some warnings that show up when a node goes away. Tested: * AR9280, STA/hostap, up to 4 vaps (staggered) * AR5416, STA/hostap, up to 4 vaps (staggered) TODO: * (Lots) more AR9380 and later testing, as I may have missed something here. * Leverage this to fix CABQ hanling for AR9380 and later chips. * Force bursted beaconing on the chips that default to staggered beacons and ensure the CABQ stuff is all sane (eg, the MORE bits that aren't being correctly set when chaining descriptors.)
2013-03-24 00:03:12 +00:00
ATH_TXQ_UNLOCK(txq);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
/*
* Hand-off packet to a hardware queue.
*/
static void
ath_tx_handoff_hw(struct ath_softc *sc, struct ath_txq *txq,
struct ath_buf *bf)
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
{
struct ath_hal *ah = sc->sc_ah;
Be (very) careful about how to add more TX DMA work. The list-based DMA engine has the following behaviour: * When the DMA engine is in the init state, you can write the first descriptor address to the QCU TxDP register and it will work. * Then when it hits the end of the list (ie, it either hits a NULL link pointer, OR it hits a descriptor with VEOL set) the QCU stops, and the TxDP points to the last descriptor that was transmitted. * Then when you want to transmit a new frame, you can then either: + write the head of the new list into TxDP, or + you write the head of the new list into the link pointer of the last completed descriptor (ie, where TxDP points), then kick TxE to restart transmission on that QCU> * The hardware then will re-read the descriptor to pick up the link pointer and then jump to that. Now, the quirks: * If you write a TxDP when there's been no previous TxDP (ie, it's 0), it works. * If you write a TxDP in any other instance, the TxDP write may actually fail. Thus, when you start transmission, it will re-read the last transmitted descriptor to get the link pointer, NOT just start a new transmission. So the correct thing to do here is: * ALWAYS use the holding descriptor (ie, the last transmitted descriptor that we've kept safe) and use the link pointer in _THAT_ to transmit the next frame. * NEVER write to the TxDP after you've done the initial write. * .. also, don't do this whilst you're also resetting the NIC. With this in mind, the following patch does basically the above. * Since this encapsulates Sam's issues with the QCU behaviour w/ TDMA, kill the TDMA special case and replace it with the above. * Add a new TXQ flag - PUTRUNNING - which indicates that we've started DMA. * Clear that flag when DMA has been shutdown. * Ensure that we're not restarting DMA with PUTRUNNING enabled. * Fix the link pointer logic during TXQ drain - we should always ensure the link pointer does point to something if there's a list of frames. Having it be NULL as an indication that DMA has finished or during a reset causes trouble. Now, given all of this, i want to nuke axq_link from orbit. There's now HAL methods to get and set the link pointer of a descriptor, so what we should do instead is to update the right link pointer. * If there's a holding descriptor and an empty TXQ list, set the link pointer of said holding descriptor to the new frame. * If there's a non-empty TXQ list, set the link pointer of the last descriptor in the list to the new frame. * Nuke axq_link from orbit. Note: * The AR9380 doesn't need this. FIFO TX writes are atomic. As long as we don't append to a list of frames that we've already passed to the hardware, all of the above doesn't apply. The holding descriptor stuff is still needed to ensure the hardware can re-read a completed descriptor to move onto the next one, but we restart DMA by pushing in a new FIFO entry into the TX QCU. That doesn't require any real gymnastics. Tested: * AR5210, AR5211, AR5212, AR5416, AR9380 - STA mode.
2013-05-18 18:27:53 +00:00
struct ath_buf *bf_first;
/*
* Insert the frame on the outbound list and pass it on
* to the hardware. Multicast frames buffered for power
* save stations and transmit from the CAB queue are stored
* on a s/w only queue and loaded on to the CAB queue in
* the SWBA handler since frames only go out on DTIM and
* to avoid possible races.
*/
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
KASSERT((bf->bf_flags & ATH_BUF_BUSY) == 0,
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
("%s: busy status 0x%x", __func__, bf->bf_flags));
KASSERT(txq->axq_qnum != ATH_TXQ_SWQ,
("ath_tx_handoff_hw called for mcast queue"));
Be (very) careful about how to add more TX DMA work. The list-based DMA engine has the following behaviour: * When the DMA engine is in the init state, you can write the first descriptor address to the QCU TxDP register and it will work. * Then when it hits the end of the list (ie, it either hits a NULL link pointer, OR it hits a descriptor with VEOL set) the QCU stops, and the TxDP points to the last descriptor that was transmitted. * Then when you want to transmit a new frame, you can then either: + write the head of the new list into TxDP, or + you write the head of the new list into the link pointer of the last completed descriptor (ie, where TxDP points), then kick TxE to restart transmission on that QCU> * The hardware then will re-read the descriptor to pick up the link pointer and then jump to that. Now, the quirks: * If you write a TxDP when there's been no previous TxDP (ie, it's 0), it works. * If you write a TxDP in any other instance, the TxDP write may actually fail. Thus, when you start transmission, it will re-read the last transmitted descriptor to get the link pointer, NOT just start a new transmission. So the correct thing to do here is: * ALWAYS use the holding descriptor (ie, the last transmitted descriptor that we've kept safe) and use the link pointer in _THAT_ to transmit the next frame. * NEVER write to the TxDP after you've done the initial write. * .. also, don't do this whilst you're also resetting the NIC. With this in mind, the following patch does basically the above. * Since this encapsulates Sam's issues with the QCU behaviour w/ TDMA, kill the TDMA special case and replace it with the above. * Add a new TXQ flag - PUTRUNNING - which indicates that we've started DMA. * Clear that flag when DMA has been shutdown. * Ensure that we're not restarting DMA with PUTRUNNING enabled. * Fix the link pointer logic during TXQ drain - we should always ensure the link pointer does point to something if there's a list of frames. Having it be NULL as an indication that DMA has finished or during a reset causes trouble. Now, given all of this, i want to nuke axq_link from orbit. There's now HAL methods to get and set the link pointer of a descriptor, so what we should do instead is to update the right link pointer. * If there's a holding descriptor and an empty TXQ list, set the link pointer of said holding descriptor to the new frame. * If there's a non-empty TXQ list, set the link pointer of the last descriptor in the list to the new frame. * Nuke axq_link from orbit. Note: * The AR9380 doesn't need this. FIFO TX writes are atomic. As long as we don't append to a list of frames that we've already passed to the hardware, all of the above doesn't apply. The holding descriptor stuff is still needed to ensure the hardware can re-read a completed descriptor to move onto the next one, but we restart DMA by pushing in a new FIFO entry into the TX QCU. That doesn't require any real gymnastics. Tested: * AR5210, AR5211, AR5212, AR5416, AR9380 - STA mode.
2013-05-18 18:27:53 +00:00
/*
* XXX racy, should hold the PCU lock when checking this,
* and also should ensure that the TX counter is >0!
*/
KASSERT((sc->sc_inreset_cnt == 0),
("%s: TX during reset?\n", __func__));
Flesh out some slightly dirty reset/channel change serialisation code for the ath(4) driver. Currently, there's nothing stopping reset, channel change and general TX/RX from overlapping with each other. This wasn't a big deal with pre-11n traffic as it just results in some dropped frames. It's possible this may have also caused some inconsistencies and badly-setup hardware. Since locks can't be held across all of this (the Linux solution) due to LORs with the network stack locks, some state counter variables are used to track what parts of the code the driver is currently in. When the hardware is being reset, it disables the taskqueue and waits for pending interrupts, tx, rx and tx completion before it begins the reset or channel change. TX and RX both abort if called during an active reset or channel change. Finally, the reset path now doesn't flush frames if ATH_RESET_NOLOSS is set. Instead, completed TX and RX frames are passed back up to net80211 before the reset occurs. This is not without problems: * Raw frame xmit are just dropped, rather than placed on a queue. The net80211 stack should be the one which queues these frames rather than the driver. * It's all very messy. It'd be better if these hardware operations were serialised on some kind of work queue, rather than hoping they can be run in parallel. * The taskqueue block/unblock may occur in parallel with the newstate() function - which shuts down the taskqueue and restarts it once the new state is known. It's likely these operations should be refcounted so the taskqueue is restored once no other areas in the code wish to suspend operations. * .. interrupt disable/enable should likely be refcounted as well. With this work, the driver does not drop frames during stuck beacon or fatal errors and thus 11n traffic continues to run correctly. Default and full resets however do still drop frames and it's possible this may occur, causing traffic loss and session stalls. Sponsored by: Hobnob, Inc.
2011-11-18 05:06:30 +00:00
#if 0
/*
* This causes a LOR. Find out where the PCU lock is being
* held whilst the TXQ lock is grabbed - that shouldn't
* be occuring.
*/
ATH_PCU_LOCK(sc);
if (sc->sc_inreset_cnt) {
ATH_PCU_UNLOCK(sc);
DPRINTF(sc, ATH_DEBUG_RESET,
"%s: called with sc_in_reset != 0\n",
__func__);
DPRINTF(sc, ATH_DEBUG_XMIT,
"%s: queued: TXDP[%u] = %p (%p) depth %d\n",
__func__, txq->axq_qnum,
(caddr_t)bf->bf_daddr, bf->bf_desc,
txq->axq_depth);
Be (very) careful about how to add more TX DMA work. The list-based DMA engine has the following behaviour: * When the DMA engine is in the init state, you can write the first descriptor address to the QCU TxDP register and it will work. * Then when it hits the end of the list (ie, it either hits a NULL link pointer, OR it hits a descriptor with VEOL set) the QCU stops, and the TxDP points to the last descriptor that was transmitted. * Then when you want to transmit a new frame, you can then either: + write the head of the new list into TxDP, or + you write the head of the new list into the link pointer of the last completed descriptor (ie, where TxDP points), then kick TxE to restart transmission on that QCU> * The hardware then will re-read the descriptor to pick up the link pointer and then jump to that. Now, the quirks: * If you write a TxDP when there's been no previous TxDP (ie, it's 0), it works. * If you write a TxDP in any other instance, the TxDP write may actually fail. Thus, when you start transmission, it will re-read the last transmitted descriptor to get the link pointer, NOT just start a new transmission. So the correct thing to do here is: * ALWAYS use the holding descriptor (ie, the last transmitted descriptor that we've kept safe) and use the link pointer in _THAT_ to transmit the next frame. * NEVER write to the TxDP after you've done the initial write. * .. also, don't do this whilst you're also resetting the NIC. With this in mind, the following patch does basically the above. * Since this encapsulates Sam's issues with the QCU behaviour w/ TDMA, kill the TDMA special case and replace it with the above. * Add a new TXQ flag - PUTRUNNING - which indicates that we've started DMA. * Clear that flag when DMA has been shutdown. * Ensure that we're not restarting DMA with PUTRUNNING enabled. * Fix the link pointer logic during TXQ drain - we should always ensure the link pointer does point to something if there's a list of frames. Having it be NULL as an indication that DMA has finished or during a reset causes trouble. Now, given all of this, i want to nuke axq_link from orbit. There's now HAL methods to get and set the link pointer of a descriptor, so what we should do instead is to update the right link pointer. * If there's a holding descriptor and an empty TXQ list, set the link pointer of said holding descriptor to the new frame. * If there's a non-empty TXQ list, set the link pointer of the last descriptor in the list to the new frame. * Nuke axq_link from orbit. Note: * The AR9380 doesn't need this. FIFO TX writes are atomic. As long as we don't append to a list of frames that we've already passed to the hardware, all of the above doesn't apply. The holding descriptor stuff is still needed to ensure the hardware can re-read a completed descriptor to move onto the next one, but we restart DMA by pushing in a new FIFO entry into the TX QCU. That doesn't require any real gymnastics. Tested: * AR5210, AR5211, AR5212, AR5416, AR9380 - STA mode.
2013-05-18 18:27:53 +00:00
/* XXX axq_link needs to be set and updated! */
Flesh out some slightly dirty reset/channel change serialisation code for the ath(4) driver. Currently, there's nothing stopping reset, channel change and general TX/RX from overlapping with each other. This wasn't a big deal with pre-11n traffic as it just results in some dropped frames. It's possible this may have also caused some inconsistencies and badly-setup hardware. Since locks can't be held across all of this (the Linux solution) due to LORs with the network stack locks, some state counter variables are used to track what parts of the code the driver is currently in. When the hardware is being reset, it disables the taskqueue and waits for pending interrupts, tx, rx and tx completion before it begins the reset or channel change. TX and RX both abort if called during an active reset or channel change. Finally, the reset path now doesn't flush frames if ATH_RESET_NOLOSS is set. Instead, completed TX and RX frames are passed back up to net80211 before the reset occurs. This is not without problems: * Raw frame xmit are just dropped, rather than placed on a queue. The net80211 stack should be the one which queues these frames rather than the driver. * It's all very messy. It'd be better if these hardware operations were serialised on some kind of work queue, rather than hoping they can be run in parallel. * The taskqueue block/unblock may occur in parallel with the newstate() function - which shuts down the taskqueue and restarts it once the new state is known. It's likely these operations should be refcounted so the taskqueue is restored once no other areas in the code wish to suspend operations. * .. interrupt disable/enable should likely be refcounted as well. With this work, the driver does not drop frames during stuck beacon or fatal errors and thus 11n traffic continues to run correctly. Default and full resets however do still drop frames and it's possible this may occur, causing traffic loss and session stalls. Sponsored by: Hobnob, Inc.
2011-11-18 05:06:30 +00:00
ATH_TXQ_INSERT_TAIL(txq, bf, bf_list);
if (bf->bf_state.bfs_aggr)
txq->axq_aggr_depth++;
return;
}
ATH_PCU_UNLOCK(sc);
#endif
Be (very) careful about how to add more TX DMA work. The list-based DMA engine has the following behaviour: * When the DMA engine is in the init state, you can write the first descriptor address to the QCU TxDP register and it will work. * Then when it hits the end of the list (ie, it either hits a NULL link pointer, OR it hits a descriptor with VEOL set) the QCU stops, and the TxDP points to the last descriptor that was transmitted. * Then when you want to transmit a new frame, you can then either: + write the head of the new list into TxDP, or + you write the head of the new list into the link pointer of the last completed descriptor (ie, where TxDP points), then kick TxE to restart transmission on that QCU> * The hardware then will re-read the descriptor to pick up the link pointer and then jump to that. Now, the quirks: * If you write a TxDP when there's been no previous TxDP (ie, it's 0), it works. * If you write a TxDP in any other instance, the TxDP write may actually fail. Thus, when you start transmission, it will re-read the last transmitted descriptor to get the link pointer, NOT just start a new transmission. So the correct thing to do here is: * ALWAYS use the holding descriptor (ie, the last transmitted descriptor that we've kept safe) and use the link pointer in _THAT_ to transmit the next frame. * NEVER write to the TxDP after you've done the initial write. * .. also, don't do this whilst you're also resetting the NIC. With this in mind, the following patch does basically the above. * Since this encapsulates Sam's issues with the QCU behaviour w/ TDMA, kill the TDMA special case and replace it with the above. * Add a new TXQ flag - PUTRUNNING - which indicates that we've started DMA. * Clear that flag when DMA has been shutdown. * Ensure that we're not restarting DMA with PUTRUNNING enabled. * Fix the link pointer logic during TXQ drain - we should always ensure the link pointer does point to something if there's a list of frames. Having it be NULL as an indication that DMA has finished or during a reset causes trouble. Now, given all of this, i want to nuke axq_link from orbit. There's now HAL methods to get and set the link pointer of a descriptor, so what we should do instead is to update the right link pointer. * If there's a holding descriptor and an empty TXQ list, set the link pointer of said holding descriptor to the new frame. * If there's a non-empty TXQ list, set the link pointer of the last descriptor in the list to the new frame. * Nuke axq_link from orbit. Note: * The AR9380 doesn't need this. FIFO TX writes are atomic. As long as we don't append to a list of frames that we've already passed to the hardware, all of the above doesn't apply. The holding descriptor stuff is still needed to ensure the hardware can re-read a completed descriptor to move onto the next one, but we restart DMA by pushing in a new FIFO entry into the TX QCU. That doesn't require any real gymnastics. Tested: * AR5210, AR5211, AR5212, AR5416, AR9380 - STA mode.
2013-05-18 18:27:53 +00:00
ATH_TXQ_LOCK(txq);
Be (very) careful about how to add more TX DMA work. The list-based DMA engine has the following behaviour: * When the DMA engine is in the init state, you can write the first descriptor address to the QCU TxDP register and it will work. * Then when it hits the end of the list (ie, it either hits a NULL link pointer, OR it hits a descriptor with VEOL set) the QCU stops, and the TxDP points to the last descriptor that was transmitted. * Then when you want to transmit a new frame, you can then either: + write the head of the new list into TxDP, or + you write the head of the new list into the link pointer of the last completed descriptor (ie, where TxDP points), then kick TxE to restart transmission on that QCU> * The hardware then will re-read the descriptor to pick up the link pointer and then jump to that. Now, the quirks: * If you write a TxDP when there's been no previous TxDP (ie, it's 0), it works. * If you write a TxDP in any other instance, the TxDP write may actually fail. Thus, when you start transmission, it will re-read the last transmitted descriptor to get the link pointer, NOT just start a new transmission. So the correct thing to do here is: * ALWAYS use the holding descriptor (ie, the last transmitted descriptor that we've kept safe) and use the link pointer in _THAT_ to transmit the next frame. * NEVER write to the TxDP after you've done the initial write. * .. also, don't do this whilst you're also resetting the NIC. With this in mind, the following patch does basically the above. * Since this encapsulates Sam's issues with the QCU behaviour w/ TDMA, kill the TDMA special case and replace it with the above. * Add a new TXQ flag - PUTRUNNING - which indicates that we've started DMA. * Clear that flag when DMA has been shutdown. * Ensure that we're not restarting DMA with PUTRUNNING enabled. * Fix the link pointer logic during TXQ drain - we should always ensure the link pointer does point to something if there's a list of frames. Having it be NULL as an indication that DMA has finished or during a reset causes trouble. Now, given all of this, i want to nuke axq_link from orbit. There's now HAL methods to get and set the link pointer of a descriptor, so what we should do instead is to update the right link pointer. * If there's a holding descriptor and an empty TXQ list, set the link pointer of said holding descriptor to the new frame. * If there's a non-empty TXQ list, set the link pointer of the last descriptor in the list to the new frame. * Nuke axq_link from orbit. Note: * The AR9380 doesn't need this. FIFO TX writes are atomic. As long as we don't append to a list of frames that we've already passed to the hardware, all of the above doesn't apply. The holding descriptor stuff is still needed to ensure the hardware can re-read a completed descriptor to move onto the next one, but we restart DMA by pushing in a new FIFO entry into the TX QCU. That doesn't require any real gymnastics. Tested: * AR5210, AR5211, AR5212, AR5416, AR9380 - STA mode.
2013-05-18 18:27:53 +00:00
/*
* XXX TODO: if there's a holdingbf, then
* ATH_TXQ_PUTRUNNING should be clear.
*
* If there is a holdingbf and the list is empty,
* then axq_link should be pointing to the holdingbf.
*
* Otherwise it should point to the last descriptor
* in the last ath_buf.
*
* In any case, we should really ensure that we
* update the previous descriptor link pointer to
* this descriptor, regardless of all of the above state.
*
* For now this is captured by having axq_link point
* to either the holdingbf (if the TXQ list is empty)
* or the end of the list (if the TXQ list isn't empty.)
* I'd rather just kill axq_link here and do it as above.
*/
Be (very) careful about how to add more TX DMA work. The list-based DMA engine has the following behaviour: * When the DMA engine is in the init state, you can write the first descriptor address to the QCU TxDP register and it will work. * Then when it hits the end of the list (ie, it either hits a NULL link pointer, OR it hits a descriptor with VEOL set) the QCU stops, and the TxDP points to the last descriptor that was transmitted. * Then when you want to transmit a new frame, you can then either: + write the head of the new list into TxDP, or + you write the head of the new list into the link pointer of the last completed descriptor (ie, where TxDP points), then kick TxE to restart transmission on that QCU> * The hardware then will re-read the descriptor to pick up the link pointer and then jump to that. Now, the quirks: * If you write a TxDP when there's been no previous TxDP (ie, it's 0), it works. * If you write a TxDP in any other instance, the TxDP write may actually fail. Thus, when you start transmission, it will re-read the last transmitted descriptor to get the link pointer, NOT just start a new transmission. So the correct thing to do here is: * ALWAYS use the holding descriptor (ie, the last transmitted descriptor that we've kept safe) and use the link pointer in _THAT_ to transmit the next frame. * NEVER write to the TxDP after you've done the initial write. * .. also, don't do this whilst you're also resetting the NIC. With this in mind, the following patch does basically the above. * Since this encapsulates Sam's issues with the QCU behaviour w/ TDMA, kill the TDMA special case and replace it with the above. * Add a new TXQ flag - PUTRUNNING - which indicates that we've started DMA. * Clear that flag when DMA has been shutdown. * Ensure that we're not restarting DMA with PUTRUNNING enabled. * Fix the link pointer logic during TXQ drain - we should always ensure the link pointer does point to something if there's a list of frames. Having it be NULL as an indication that DMA has finished or during a reset causes trouble. Now, given all of this, i want to nuke axq_link from orbit. There's now HAL methods to get and set the link pointer of a descriptor, so what we should do instead is to update the right link pointer. * If there's a holding descriptor and an empty TXQ list, set the link pointer of said holding descriptor to the new frame. * If there's a non-empty TXQ list, set the link pointer of the last descriptor in the list to the new frame. * Nuke axq_link from orbit. Note: * The AR9380 doesn't need this. FIFO TX writes are atomic. As long as we don't append to a list of frames that we've already passed to the hardware, all of the above doesn't apply. The holding descriptor stuff is still needed to ensure the hardware can re-read a completed descriptor to move onto the next one, but we restart DMA by pushing in a new FIFO entry into the TX QCU. That doesn't require any real gymnastics. Tested: * AR5210, AR5211, AR5212, AR5416, AR9380 - STA mode.
2013-05-18 18:27:53 +00:00
/*
* Append the frame to the TX queue.
*/
ATH_TXQ_INSERT_TAIL(txq, bf, bf_list);
ATH_KTR(sc, ATH_KTR_TX, 3,
"ath_tx_handoff: non-tdma: txq=%u, add bf=%p "
"depth=%d",
txq->axq_qnum,
bf,
txq->axq_depth);
/*
* If there's a link pointer, update it.
*
* XXX we should replace this with the above logic, just
* to kill axq_link with fire.
*/
if (txq->axq_link != NULL) {
*txq->axq_link = bf->bf_daddr;
DPRINTF(sc, ATH_DEBUG_XMIT,
"%s: link[%u](%p)=%p (%p) depth %d\n", __func__,
txq->axq_qnum, txq->axq_link,
(caddr_t)bf->bf_daddr, bf->bf_desc,
txq->axq_depth);
Be (very) careful about how to add more TX DMA work. The list-based DMA engine has the following behaviour: * When the DMA engine is in the init state, you can write the first descriptor address to the QCU TxDP register and it will work. * Then when it hits the end of the list (ie, it either hits a NULL link pointer, OR it hits a descriptor with VEOL set) the QCU stops, and the TxDP points to the last descriptor that was transmitted. * Then when you want to transmit a new frame, you can then either: + write the head of the new list into TxDP, or + you write the head of the new list into the link pointer of the last completed descriptor (ie, where TxDP points), then kick TxE to restart transmission on that QCU> * The hardware then will re-read the descriptor to pick up the link pointer and then jump to that. Now, the quirks: * If you write a TxDP when there's been no previous TxDP (ie, it's 0), it works. * If you write a TxDP in any other instance, the TxDP write may actually fail. Thus, when you start transmission, it will re-read the last transmitted descriptor to get the link pointer, NOT just start a new transmission. So the correct thing to do here is: * ALWAYS use the holding descriptor (ie, the last transmitted descriptor that we've kept safe) and use the link pointer in _THAT_ to transmit the next frame. * NEVER write to the TxDP after you've done the initial write. * .. also, don't do this whilst you're also resetting the NIC. With this in mind, the following patch does basically the above. * Since this encapsulates Sam's issues with the QCU behaviour w/ TDMA, kill the TDMA special case and replace it with the above. * Add a new TXQ flag - PUTRUNNING - which indicates that we've started DMA. * Clear that flag when DMA has been shutdown. * Ensure that we're not restarting DMA with PUTRUNNING enabled. * Fix the link pointer logic during TXQ drain - we should always ensure the link pointer does point to something if there's a list of frames. Having it be NULL as an indication that DMA has finished or during a reset causes trouble. Now, given all of this, i want to nuke axq_link from orbit. There's now HAL methods to get and set the link pointer of a descriptor, so what we should do instead is to update the right link pointer. * If there's a holding descriptor and an empty TXQ list, set the link pointer of said holding descriptor to the new frame. * If there's a non-empty TXQ list, set the link pointer of the last descriptor in the list to the new frame. * Nuke axq_link from orbit. Note: * The AR9380 doesn't need this. FIFO TX writes are atomic. As long as we don't append to a list of frames that we've already passed to the hardware, all of the above doesn't apply. The holding descriptor stuff is still needed to ensure the hardware can re-read a completed descriptor to move onto the next one, but we restart DMA by pushing in a new FIFO entry into the TX QCU. That doesn't require any real gymnastics. Tested: * AR5210, AR5211, AR5212, AR5416, AR9380 - STA mode.
2013-05-18 18:27:53 +00:00
ATH_KTR(sc, ATH_KTR_TX, 5,
"ath_tx_handoff: non-tdma: link[%u](%p)=%p (%p) "
"lastds=%d",
txq->axq_qnum, txq->axq_link,
(caddr_t)bf->bf_daddr, bf->bf_desc,
bf->bf_lastds);
}
Be (very) careful about how to add more TX DMA work. The list-based DMA engine has the following behaviour: * When the DMA engine is in the init state, you can write the first descriptor address to the QCU TxDP register and it will work. * Then when it hits the end of the list (ie, it either hits a NULL link pointer, OR it hits a descriptor with VEOL set) the QCU stops, and the TxDP points to the last descriptor that was transmitted. * Then when you want to transmit a new frame, you can then either: + write the head of the new list into TxDP, or + you write the head of the new list into the link pointer of the last completed descriptor (ie, where TxDP points), then kick TxE to restart transmission on that QCU> * The hardware then will re-read the descriptor to pick up the link pointer and then jump to that. Now, the quirks: * If you write a TxDP when there's been no previous TxDP (ie, it's 0), it works. * If you write a TxDP in any other instance, the TxDP write may actually fail. Thus, when you start transmission, it will re-read the last transmitted descriptor to get the link pointer, NOT just start a new transmission. So the correct thing to do here is: * ALWAYS use the holding descriptor (ie, the last transmitted descriptor that we've kept safe) and use the link pointer in _THAT_ to transmit the next frame. * NEVER write to the TxDP after you've done the initial write. * .. also, don't do this whilst you're also resetting the NIC. With this in mind, the following patch does basically the above. * Since this encapsulates Sam's issues with the QCU behaviour w/ TDMA, kill the TDMA special case and replace it with the above. * Add a new TXQ flag - PUTRUNNING - which indicates that we've started DMA. * Clear that flag when DMA has been shutdown. * Ensure that we're not restarting DMA with PUTRUNNING enabled. * Fix the link pointer logic during TXQ drain - we should always ensure the link pointer does point to something if there's a list of frames. Having it be NULL as an indication that DMA has finished or during a reset causes trouble. Now, given all of this, i want to nuke axq_link from orbit. There's now HAL methods to get and set the link pointer of a descriptor, so what we should do instead is to update the right link pointer. * If there's a holding descriptor and an empty TXQ list, set the link pointer of said holding descriptor to the new frame. * If there's a non-empty TXQ list, set the link pointer of the last descriptor in the list to the new frame. * Nuke axq_link from orbit. Note: * The AR9380 doesn't need this. FIFO TX writes are atomic. As long as we don't append to a list of frames that we've already passed to the hardware, all of the above doesn't apply. The holding descriptor stuff is still needed to ensure the hardware can re-read a completed descriptor to move onto the next one, but we restart DMA by pushing in a new FIFO entry into the TX QCU. That doesn't require any real gymnastics. Tested: * AR5210, AR5211, AR5212, AR5416, AR9380 - STA mode.
2013-05-18 18:27:53 +00:00
/*
* If we've not pushed anything into the hardware yet,
* push the head of the queue into the TxDP.
*
* Once we've started DMA, there's no guarantee that
* updating the TxDP with a new value will actually work.
* So we just don't do that - if we hit the end of the list,
* we keep that buffer around (the "holding buffer") and
* re-start DMA by updating the link pointer of _that_
* descriptor and then restart DMA.
*/
if (! (txq->axq_flags & ATH_TXQ_PUTRUNNING)) {
bf_first = TAILQ_FIRST(&txq->axq_q);
txq->axq_flags |= ATH_TXQ_PUTRUNNING;
ath_hal_puttxbuf(ah, txq->axq_qnum, bf_first->bf_daddr);
DPRINTF(sc, ATH_DEBUG_XMIT,
"%s: TXDP[%u] = %p (%p) depth %d\n",
__func__, txq->axq_qnum,
(caddr_t)bf_first->bf_daddr, bf_first->bf_desc,
txq->axq_depth);
ATH_KTR(sc, ATH_KTR_TX, 5,
"ath_tx_handoff: TXDP[%u] = %p (%p) "
"lastds=%p depth %d",
txq->axq_qnum,
(caddr_t)bf_first->bf_daddr, bf_first->bf_desc,
bf_first->bf_lastds,
txq->axq_depth);
}
Be (very) careful about how to add more TX DMA work. The list-based DMA engine has the following behaviour: * When the DMA engine is in the init state, you can write the first descriptor address to the QCU TxDP register and it will work. * Then when it hits the end of the list (ie, it either hits a NULL link pointer, OR it hits a descriptor with VEOL set) the QCU stops, and the TxDP points to the last descriptor that was transmitted. * Then when you want to transmit a new frame, you can then either: + write the head of the new list into TxDP, or + you write the head of the new list into the link pointer of the last completed descriptor (ie, where TxDP points), then kick TxE to restart transmission on that QCU> * The hardware then will re-read the descriptor to pick up the link pointer and then jump to that. Now, the quirks: * If you write a TxDP when there's been no previous TxDP (ie, it's 0), it works. * If you write a TxDP in any other instance, the TxDP write may actually fail. Thus, when you start transmission, it will re-read the last transmitted descriptor to get the link pointer, NOT just start a new transmission. So the correct thing to do here is: * ALWAYS use the holding descriptor (ie, the last transmitted descriptor that we've kept safe) and use the link pointer in _THAT_ to transmit the next frame. * NEVER write to the TxDP after you've done the initial write. * .. also, don't do this whilst you're also resetting the NIC. With this in mind, the following patch does basically the above. * Since this encapsulates Sam's issues with the QCU behaviour w/ TDMA, kill the TDMA special case and replace it with the above. * Add a new TXQ flag - PUTRUNNING - which indicates that we've started DMA. * Clear that flag when DMA has been shutdown. * Ensure that we're not restarting DMA with PUTRUNNING enabled. * Fix the link pointer logic during TXQ drain - we should always ensure the link pointer does point to something if there's a list of frames. Having it be NULL as an indication that DMA has finished or during a reset causes trouble. Now, given all of this, i want to nuke axq_link from orbit. There's now HAL methods to get and set the link pointer of a descriptor, so what we should do instead is to update the right link pointer. * If there's a holding descriptor and an empty TXQ list, set the link pointer of said holding descriptor to the new frame. * If there's a non-empty TXQ list, set the link pointer of the last descriptor in the list to the new frame. * Nuke axq_link from orbit. Note: * The AR9380 doesn't need this. FIFO TX writes are atomic. As long as we don't append to a list of frames that we've already passed to the hardware, all of the above doesn't apply. The holding descriptor stuff is still needed to ensure the hardware can re-read a completed descriptor to move onto the next one, but we restart DMA by pushing in a new FIFO entry into the TX QCU. That doesn't require any real gymnastics. Tested: * AR5210, AR5211, AR5212, AR5416, AR9380 - STA mode.
2013-05-18 18:27:53 +00:00
/*
* Ensure that the bf TXQ matches this TXQ, so later
* checking and holding buffer manipulation is sane.
*/
if (bf->bf_state.bfs_tx_queue != txq->axq_qnum) {
DPRINTF(sc, ATH_DEBUG_XMIT,
Be (very) careful about how to add more TX DMA work. The list-based DMA engine has the following behaviour: * When the DMA engine is in the init state, you can write the first descriptor address to the QCU TxDP register and it will work. * Then when it hits the end of the list (ie, it either hits a NULL link pointer, OR it hits a descriptor with VEOL set) the QCU stops, and the TxDP points to the last descriptor that was transmitted. * Then when you want to transmit a new frame, you can then either: + write the head of the new list into TxDP, or + you write the head of the new list into the link pointer of the last completed descriptor (ie, where TxDP points), then kick TxE to restart transmission on that QCU> * The hardware then will re-read the descriptor to pick up the link pointer and then jump to that. Now, the quirks: * If you write a TxDP when there's been no previous TxDP (ie, it's 0), it works. * If you write a TxDP in any other instance, the TxDP write may actually fail. Thus, when you start transmission, it will re-read the last transmitted descriptor to get the link pointer, NOT just start a new transmission. So the correct thing to do here is: * ALWAYS use the holding descriptor (ie, the last transmitted descriptor that we've kept safe) and use the link pointer in _THAT_ to transmit the next frame. * NEVER write to the TxDP after you've done the initial write. * .. also, don't do this whilst you're also resetting the NIC. With this in mind, the following patch does basically the above. * Since this encapsulates Sam's issues with the QCU behaviour w/ TDMA, kill the TDMA special case and replace it with the above. * Add a new TXQ flag - PUTRUNNING - which indicates that we've started DMA. * Clear that flag when DMA has been shutdown. * Ensure that we're not restarting DMA with PUTRUNNING enabled. * Fix the link pointer logic during TXQ drain - we should always ensure the link pointer does point to something if there's a list of frames. Having it be NULL as an indication that DMA has finished or during a reset causes trouble. Now, given all of this, i want to nuke axq_link from orbit. There's now HAL methods to get and set the link pointer of a descriptor, so what we should do instead is to update the right link pointer. * If there's a holding descriptor and an empty TXQ list, set the link pointer of said holding descriptor to the new frame. * If there's a non-empty TXQ list, set the link pointer of the last descriptor in the list to the new frame. * Nuke axq_link from orbit. Note: * The AR9380 doesn't need this. FIFO TX writes are atomic. As long as we don't append to a list of frames that we've already passed to the hardware, all of the above doesn't apply. The holding descriptor stuff is still needed to ensure the hardware can re-read a completed descriptor to move onto the next one, but we restart DMA by pushing in a new FIFO entry into the TX QCU. That doesn't require any real gymnastics. Tested: * AR5210, AR5211, AR5212, AR5416, AR9380 - STA mode.
2013-05-18 18:27:53 +00:00
"%s: bf=%p, bfs_tx_queue=%d, axq_qnum=%d\n",
__func__, bf, bf->bf_state.bfs_tx_queue,
Be (very) careful about how to add more TX DMA work. The list-based DMA engine has the following behaviour: * When the DMA engine is in the init state, you can write the first descriptor address to the QCU TxDP register and it will work. * Then when it hits the end of the list (ie, it either hits a NULL link pointer, OR it hits a descriptor with VEOL set) the QCU stops, and the TxDP points to the last descriptor that was transmitted. * Then when you want to transmit a new frame, you can then either: + write the head of the new list into TxDP, or + you write the head of the new list into the link pointer of the last completed descriptor (ie, where TxDP points), then kick TxE to restart transmission on that QCU> * The hardware then will re-read the descriptor to pick up the link pointer and then jump to that. Now, the quirks: * If you write a TxDP when there's been no previous TxDP (ie, it's 0), it works. * If you write a TxDP in any other instance, the TxDP write may actually fail. Thus, when you start transmission, it will re-read the last transmitted descriptor to get the link pointer, NOT just start a new transmission. So the correct thing to do here is: * ALWAYS use the holding descriptor (ie, the last transmitted descriptor that we've kept safe) and use the link pointer in _THAT_ to transmit the next frame. * NEVER write to the TxDP after you've done the initial write. * .. also, don't do this whilst you're also resetting the NIC. With this in mind, the following patch does basically the above. * Since this encapsulates Sam's issues with the QCU behaviour w/ TDMA, kill the TDMA special case and replace it with the above. * Add a new TXQ flag - PUTRUNNING - which indicates that we've started DMA. * Clear that flag when DMA has been shutdown. * Ensure that we're not restarting DMA with PUTRUNNING enabled. * Fix the link pointer logic during TXQ drain - we should always ensure the link pointer does point to something if there's a list of frames. Having it be NULL as an indication that DMA has finished or during a reset causes trouble. Now, given all of this, i want to nuke axq_link from orbit. There's now HAL methods to get and set the link pointer of a descriptor, so what we should do instead is to update the right link pointer. * If there's a holding descriptor and an empty TXQ list, set the link pointer of said holding descriptor to the new frame. * If there's a non-empty TXQ list, set the link pointer of the last descriptor in the list to the new frame. * Nuke axq_link from orbit. Note: * The AR9380 doesn't need this. FIFO TX writes are atomic. As long as we don't append to a list of frames that we've already passed to the hardware, all of the above doesn't apply. The holding descriptor stuff is still needed to ensure the hardware can re-read a completed descriptor to move onto the next one, but we restart DMA by pushing in a new FIFO entry into the TX QCU. That doesn't require any real gymnastics. Tested: * AR5210, AR5211, AR5212, AR5416, AR9380 - STA mode.
2013-05-18 18:27:53 +00:00
txq->axq_qnum);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
Be (very) careful about how to add more TX DMA work. The list-based DMA engine has the following behaviour: * When the DMA engine is in the init state, you can write the first descriptor address to the QCU TxDP register and it will work. * Then when it hits the end of the list (ie, it either hits a NULL link pointer, OR it hits a descriptor with VEOL set) the QCU stops, and the TxDP points to the last descriptor that was transmitted. * Then when you want to transmit a new frame, you can then either: + write the head of the new list into TxDP, or + you write the head of the new list into the link pointer of the last completed descriptor (ie, where TxDP points), then kick TxE to restart transmission on that QCU> * The hardware then will re-read the descriptor to pick up the link pointer and then jump to that. Now, the quirks: * If you write a TxDP when there's been no previous TxDP (ie, it's 0), it works. * If you write a TxDP in any other instance, the TxDP write may actually fail. Thus, when you start transmission, it will re-read the last transmitted descriptor to get the link pointer, NOT just start a new transmission. So the correct thing to do here is: * ALWAYS use the holding descriptor (ie, the last transmitted descriptor that we've kept safe) and use the link pointer in _THAT_ to transmit the next frame. * NEVER write to the TxDP after you've done the initial write. * .. also, don't do this whilst you're also resetting the NIC. With this in mind, the following patch does basically the above. * Since this encapsulates Sam's issues with the QCU behaviour w/ TDMA, kill the TDMA special case and replace it with the above. * Add a new TXQ flag - PUTRUNNING - which indicates that we've started DMA. * Clear that flag when DMA has been shutdown. * Ensure that we're not restarting DMA with PUTRUNNING enabled. * Fix the link pointer logic during TXQ drain - we should always ensure the link pointer does point to something if there's a list of frames. Having it be NULL as an indication that DMA has finished or during a reset causes trouble. Now, given all of this, i want to nuke axq_link from orbit. There's now HAL methods to get and set the link pointer of a descriptor, so what we should do instead is to update the right link pointer. * If there's a holding descriptor and an empty TXQ list, set the link pointer of said holding descriptor to the new frame. * If there's a non-empty TXQ list, set the link pointer of the last descriptor in the list to the new frame. * Nuke axq_link from orbit. Note: * The AR9380 doesn't need this. FIFO TX writes are atomic. As long as we don't append to a list of frames that we've already passed to the hardware, all of the above doesn't apply. The holding descriptor stuff is still needed to ensure the hardware can re-read a completed descriptor to move onto the next one, but we restart DMA by pushing in a new FIFO entry into the TX QCU. That doesn't require any real gymnastics. Tested: * AR5210, AR5211, AR5212, AR5416, AR9380 - STA mode.
2013-05-18 18:27:53 +00:00
/*
* Track aggregate queue depth.
*/
if (bf->bf_state.bfs_aggr)
txq->axq_aggr_depth++;
/*
* Update the link pointer.
*/
ath_hal_gettxdesclinkptr(ah, bf->bf_lastds, &txq->axq_link);
/*
* Start DMA.
*
* If we wrote a TxDP above, DMA will start from here.
*
* If DMA is running, it'll do nothing.
*
* If the DMA engine hit the end of the QCU list (ie LINK=NULL,
* or VEOL) then it stops at the last transmitted write.
* We then append a new frame by updating the link pointer
* in that descriptor and then kick TxE here; it will re-read
* that last descriptor and find the new descriptor to transmit.
*
* This is why we keep the holding descriptor around.
*/
ath_hal_txstart(ah, txq->axq_qnum);
ATH_TXQ_UNLOCK(txq);
ATH_KTR(sc, ATH_KTR_TX, 1,
"ath_tx_handoff: txq=%u, txstart", txq->axq_qnum);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Restart TX DMA for the given TXQ.
*
* This must be called whether the queue is empty or not.
*/
static void
ath_legacy_tx_dma_restart(struct ath_softc *sc, struct ath_txq *txq)
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
{
struct ath_buf *bf, *bf_last;
Overhaul the TXQ locking (again!) as part of some beacon/cabq timing related issues. Moving the TX locking under one lock made things easier to progress on but it had one important side-effect - it increased the latency when handling CABQ setup when sending beacons. This commit introduces a bunch of new changes and a few unrelated changs that are just easier to lump in here. The aim is to have the CABQ locking separate from other locking. The CABQ transmit path in the beacon process thus doesn't have to grab the general TX lock, reducing lock contention/latency and making it more likely that we'll make the beacon TX timing. The second half of this commit is the CABQ related setup changes needed for sane looking EDMA CABQ support. Right now the EDMA TX code naively assumes that only one frame (MPDU or A-MPDU) is being pushed into each FIFO slot. For the CABQ this isn't true - a whole list of frames is being pushed in - and thus CABQ handling breaks very quickly. The aim here is to setup the CABQ list and then push _that list_ to the hardware for transmission. I can then extend the EDMA TX code to stamp that list as being "one" FIFO entry (likely by tagging the last buffer in that list as "FIFO END") so the EDMA TX completion code correctly tracks things. Major: * Migrate the per-TXQ add/removal locking back to per-TXQ, rather than a single lock. * Leave the software queue side of things under the ATH_TX_LOCK lock, (continuing) to serialise things as they are. * Add a new function which is called whenever there's a beacon miss, to print out some debugging. This is primarily designed to help me figure out if the beacon miss events are due to a noisy environment, issues with the PHY/MAC, or other. * Move the CABQ setup/enable to occur _after_ all the VAPs have been looked at. This means that for multiple VAPS in bursted mode, the CABQ gets primed once all VAPs are checked, rather than being primed on the first VAP and then having frames appended after this. Minor: * Add a (disabled) twiddle to let me enable/disable cabq traffic. It's primarily there to let me easily debug what's going on with beacon and CABQ setup/traffic; there's some DMA engine hangs which I'm finally trying to trace down. * Clear bf_next when flushing frames; it should quieten some warnings that show up when a node goes away. Tested: * AR9280, STA/hostap, up to 4 vaps (staggered) * AR5416, STA/hostap, up to 4 vaps (staggered) TODO: * (Lots) more AR9380 and later testing, as I may have missed something here. * Leverage this to fix CABQ hanling for AR9380 and later chips. * Force bursted beaconing on the chips that default to staggered beacons and ensure the CABQ stuff is all sane (eg, the MORE bits that aren't being correctly set when chaining descriptors.)
2013-03-24 00:03:12 +00:00
ATH_TXQ_LOCK_ASSERT(txq);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* XXX make this ATH_TXQ_FIRST */
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
bf = TAILQ_FIRST(&txq->axq_q);
bf_last = ATH_TXQ_LAST(txq, axq_q_s);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (bf == NULL)
return;
Be (very) careful about how to add more TX DMA work. The list-based DMA engine has the following behaviour: * When the DMA engine is in the init state, you can write the first descriptor address to the QCU TxDP register and it will work. * Then when it hits the end of the list (ie, it either hits a NULL link pointer, OR it hits a descriptor with VEOL set) the QCU stops, and the TxDP points to the last descriptor that was transmitted. * Then when you want to transmit a new frame, you can then either: + write the head of the new list into TxDP, or + you write the head of the new list into the link pointer of the last completed descriptor (ie, where TxDP points), then kick TxE to restart transmission on that QCU> * The hardware then will re-read the descriptor to pick up the link pointer and then jump to that. Now, the quirks: * If you write a TxDP when there's been no previous TxDP (ie, it's 0), it works. * If you write a TxDP in any other instance, the TxDP write may actually fail. Thus, when you start transmission, it will re-read the last transmitted descriptor to get the link pointer, NOT just start a new transmission. So the correct thing to do here is: * ALWAYS use the holding descriptor (ie, the last transmitted descriptor that we've kept safe) and use the link pointer in _THAT_ to transmit the next frame. * NEVER write to the TxDP after you've done the initial write. * .. also, don't do this whilst you're also resetting the NIC. With this in mind, the following patch does basically the above. * Since this encapsulates Sam's issues with the QCU behaviour w/ TDMA, kill the TDMA special case and replace it with the above. * Add a new TXQ flag - PUTRUNNING - which indicates that we've started DMA. * Clear that flag when DMA has been shutdown. * Ensure that we're not restarting DMA with PUTRUNNING enabled. * Fix the link pointer logic during TXQ drain - we should always ensure the link pointer does point to something if there's a list of frames. Having it be NULL as an indication that DMA has finished or during a reset causes trouble. Now, given all of this, i want to nuke axq_link from orbit. There's now HAL methods to get and set the link pointer of a descriptor, so what we should do instead is to update the right link pointer. * If there's a holding descriptor and an empty TXQ list, set the link pointer of said holding descriptor to the new frame. * If there's a non-empty TXQ list, set the link pointer of the last descriptor in the list to the new frame. * Nuke axq_link from orbit. Note: * The AR9380 doesn't need this. FIFO TX writes are atomic. As long as we don't append to a list of frames that we've already passed to the hardware, all of the above doesn't apply. The holding descriptor stuff is still needed to ensure the hardware can re-read a completed descriptor to move onto the next one, but we restart DMA by pushing in a new FIFO entry into the TX QCU. That doesn't require any real gymnastics. Tested: * AR5210, AR5211, AR5212, AR5416, AR9380 - STA mode.
2013-05-18 18:27:53 +00:00
DPRINTF(sc, ATH_DEBUG_RESET,
"%s: Q%d: bf=%p, bf_last=%p, daddr=0x%08x\n",
__func__,
txq->axq_qnum,
bf,
bf_last,
(uint32_t) bf->bf_daddr);
2013-05-19 01:33:17 +00:00
#ifdef ATH_DEBUG
Be (very) careful about how to add more TX DMA work. The list-based DMA engine has the following behaviour: * When the DMA engine is in the init state, you can write the first descriptor address to the QCU TxDP register and it will work. * Then when it hits the end of the list (ie, it either hits a NULL link pointer, OR it hits a descriptor with VEOL set) the QCU stops, and the TxDP points to the last descriptor that was transmitted. * Then when you want to transmit a new frame, you can then either: + write the head of the new list into TxDP, or + you write the head of the new list into the link pointer of the last completed descriptor (ie, where TxDP points), then kick TxE to restart transmission on that QCU> * The hardware then will re-read the descriptor to pick up the link pointer and then jump to that. Now, the quirks: * If you write a TxDP when there's been no previous TxDP (ie, it's 0), it works. * If you write a TxDP in any other instance, the TxDP write may actually fail. Thus, when you start transmission, it will re-read the last transmitted descriptor to get the link pointer, NOT just start a new transmission. So the correct thing to do here is: * ALWAYS use the holding descriptor (ie, the last transmitted descriptor that we've kept safe) and use the link pointer in _THAT_ to transmit the next frame. * NEVER write to the TxDP after you've done the initial write. * .. also, don't do this whilst you're also resetting the NIC. With this in mind, the following patch does basically the above. * Since this encapsulates Sam's issues with the QCU behaviour w/ TDMA, kill the TDMA special case and replace it with the above. * Add a new TXQ flag - PUTRUNNING - which indicates that we've started DMA. * Clear that flag when DMA has been shutdown. * Ensure that we're not restarting DMA with PUTRUNNING enabled. * Fix the link pointer logic during TXQ drain - we should always ensure the link pointer does point to something if there's a list of frames. Having it be NULL as an indication that DMA has finished or during a reset causes trouble. Now, given all of this, i want to nuke axq_link from orbit. There's now HAL methods to get and set the link pointer of a descriptor, so what we should do instead is to update the right link pointer. * If there's a holding descriptor and an empty TXQ list, set the link pointer of said holding descriptor to the new frame. * If there's a non-empty TXQ list, set the link pointer of the last descriptor in the list to the new frame. * Nuke axq_link from orbit. Note: * The AR9380 doesn't need this. FIFO TX writes are atomic. As long as we don't append to a list of frames that we've already passed to the hardware, all of the above doesn't apply. The holding descriptor stuff is still needed to ensure the hardware can re-read a completed descriptor to move onto the next one, but we restart DMA by pushing in a new FIFO entry into the TX QCU. That doesn't require any real gymnastics. Tested: * AR5210, AR5211, AR5212, AR5416, AR9380 - STA mode.
2013-05-18 18:27:53 +00:00
if (sc->sc_debug & ATH_DEBUG_RESET)
ath_tx_dump(sc, txq);
2013-05-19 01:33:17 +00:00
#endif
Be (very) careful about how to add more TX DMA work. The list-based DMA engine has the following behaviour: * When the DMA engine is in the init state, you can write the first descriptor address to the QCU TxDP register and it will work. * Then when it hits the end of the list (ie, it either hits a NULL link pointer, OR it hits a descriptor with VEOL set) the QCU stops, and the TxDP points to the last descriptor that was transmitted. * Then when you want to transmit a new frame, you can then either: + write the head of the new list into TxDP, or + you write the head of the new list into the link pointer of the last completed descriptor (ie, where TxDP points), then kick TxE to restart transmission on that QCU> * The hardware then will re-read the descriptor to pick up the link pointer and then jump to that. Now, the quirks: * If you write a TxDP when there's been no previous TxDP (ie, it's 0), it works. * If you write a TxDP in any other instance, the TxDP write may actually fail. Thus, when you start transmission, it will re-read the last transmitted descriptor to get the link pointer, NOT just start a new transmission. So the correct thing to do here is: * ALWAYS use the holding descriptor (ie, the last transmitted descriptor that we've kept safe) and use the link pointer in _THAT_ to transmit the next frame. * NEVER write to the TxDP after you've done the initial write. * .. also, don't do this whilst you're also resetting the NIC. With this in mind, the following patch does basically the above. * Since this encapsulates Sam's issues with the QCU behaviour w/ TDMA, kill the TDMA special case and replace it with the above. * Add a new TXQ flag - PUTRUNNING - which indicates that we've started DMA. * Clear that flag when DMA has been shutdown. * Ensure that we're not restarting DMA with PUTRUNNING enabled. * Fix the link pointer logic during TXQ drain - we should always ensure the link pointer does point to something if there's a list of frames. Having it be NULL as an indication that DMA has finished or during a reset causes trouble. Now, given all of this, i want to nuke axq_link from orbit. There's now HAL methods to get and set the link pointer of a descriptor, so what we should do instead is to update the right link pointer. * If there's a holding descriptor and an empty TXQ list, set the link pointer of said holding descriptor to the new frame. * If there's a non-empty TXQ list, set the link pointer of the last descriptor in the list to the new frame. * Nuke axq_link from orbit. Note: * The AR9380 doesn't need this. FIFO TX writes are atomic. As long as we don't append to a list of frames that we've already passed to the hardware, all of the above doesn't apply. The holding descriptor stuff is still needed to ensure the hardware can re-read a completed descriptor to move onto the next one, but we restart DMA by pushing in a new FIFO entry into the TX QCU. That doesn't require any real gymnastics. Tested: * AR5210, AR5211, AR5212, AR5416, AR9380 - STA mode.
2013-05-18 18:27:53 +00:00
/*
* This is called from a restart, so DMA is known to be
* completely stopped.
*/
KASSERT((!(txq->axq_flags & ATH_TXQ_PUTRUNNING)),
("%s: Q%d: called with PUTRUNNING=1\n",
__func__,
txq->axq_qnum));
ath_hal_puttxbuf(sc->sc_ah, txq->axq_qnum, bf->bf_daddr);
txq->axq_flags |= ATH_TXQ_PUTRUNNING;
2013-05-19 01:33:17 +00:00
ath_hal_gettxdesclinkptr(sc->sc_ah, bf_last->bf_lastds,
&txq->axq_link);
ath_hal_txstart(sc->sc_ah, txq->axq_qnum);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
/*
* Hand off a packet to the hardware (or mcast queue.)
*
* The relevant hardware txq should be locked.
*/
static void
ath_legacy_xmit_handoff(struct ath_softc *sc, struct ath_txq *txq,
struct ath_buf *bf)
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
{
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
#ifdef ATH_DEBUG_ALQ
if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_EDMA_TXDESC))
ath_tx_alq_post(sc, bf);
#endif
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (txq->axq_qnum == ATH_TXQ_SWQ)
ath_tx_handoff_mcast(sc, txq, bf);
else
ath_tx_handoff_hw(sc, txq, bf);
}
static int
ath_tx_tag_crypto(struct ath_softc *sc, struct ieee80211_node *ni,
struct mbuf *m0, int iswep, int isfrag, int *hdrlen, int *pktlen,
int *keyix)
{
DPRINTF(sc, ATH_DEBUG_XMIT,
"%s: hdrlen=%d, pktlen=%d, isfrag=%d, iswep=%d, m0=%p\n",
__func__,
*hdrlen,
*pktlen,
isfrag,
iswep,
m0);
if (iswep) {
const struct ieee80211_cipher *cip;
struct ieee80211_key *k;
/*
* Construct the 802.11 header+trailer for an encrypted
* frame. The only reason this can fail is because of an
* unknown or unsupported cipher/key type.
*/
k = ieee80211_crypto_encap(ni, m0);
if (k == NULL) {
/*
* This can happen when the key is yanked after the
* frame was queued. Just discard the frame; the
* 802.11 layer counts failures and provides
* debugging/diagnostics.
*/
return (0);
}
/*
* Adjust the packet + header lengths for the crypto
* additions and calculate the h/w key index. When
* a s/w mic is done the frame will have had any mic
* added to it prior to entry so m0->m_pkthdr.len will
* account for it. Otherwise we need to add it to the
* packet length.
*/
cip = k->wk_cipher;
(*hdrlen) += cip->ic_header;
(*pktlen) += cip->ic_header + cip->ic_trailer;
/* NB: frags always have any TKIP MIC done in s/w */
if ((k->wk_flags & IEEE80211_KEY_SWMIC) == 0 && !isfrag)
(*pktlen) += cip->ic_miclen;
(*keyix) = k->wk_keyix;
} else if (ni->ni_ucastkey.wk_cipher == &ieee80211_cipher_none) {
/*
* Use station key cache slot, if assigned.
*/
(*keyix) = ni->ni_ucastkey.wk_keyix;
if ((*keyix) == IEEE80211_KEYIX_NONE)
(*keyix) = HAL_TXKEYIX_INVALID;
} else
(*keyix) = HAL_TXKEYIX_INVALID;
return (1);
}
/*
* Calculate whether interoperability protection is required for
* this frame.
*
* This requires the rate control information be filled in,
* as the protection requirement depends upon the current
* operating mode / PHY.
*/
static void
ath_tx_calc_protection(struct ath_softc *sc, struct ath_buf *bf)
{
struct ieee80211_frame *wh;
uint8_t rix;
uint16_t flags;
int shortPreamble;
const HAL_RATE_TABLE *rt = sc->sc_currates;
struct ifnet *ifp = sc->sc_ifp;
struct ieee80211com *ic = ifp->if_l2com;
flags = bf->bf_state.bfs_txflags;
rix = bf->bf_state.bfs_rc[0].rix;
shortPreamble = bf->bf_state.bfs_shpream;
wh = mtod(bf->bf_m, struct ieee80211_frame *);
/*
* If 802.11g protection is enabled, determine whether
* to use RTS/CTS or just CTS. Note that this is only
* done for OFDM unicast frames.
*/
if ((ic->ic_flags & IEEE80211_F_USEPROT) &&
rt->info[rix].phy == IEEE80211_T_OFDM &&
(flags & HAL_TXDESC_NOACK) == 0) {
bf->bf_state.bfs_doprot = 1;
/* XXX fragments must use CCK rates w/ protection */
if (ic->ic_protmode == IEEE80211_PROT_RTSCTS) {
flags |= HAL_TXDESC_RTSENA;
} else if (ic->ic_protmode == IEEE80211_PROT_CTSONLY) {
flags |= HAL_TXDESC_CTSENA;
}
/*
* For frags it would be desirable to use the
* highest CCK rate for RTS/CTS. But stations
* farther away may detect it at a lower CCK rate
* so use the configured protection rate instead
* (for now).
*/
sc->sc_stats.ast_tx_protect++;
}
/*
* If 11n protection is enabled and it's a HT frame,
* enable RTS.
*
* XXX ic_htprotmode or ic_curhtprotmode?
* XXX should it_htprotmode only matter if ic_curhtprotmode
* XXX indicates it's not a HT pure environment?
*/
if ((ic->ic_htprotmode == IEEE80211_PROT_RTSCTS) &&
rt->info[rix].phy == IEEE80211_T_HT &&
(flags & HAL_TXDESC_NOACK) == 0) {
flags |= HAL_TXDESC_RTSENA;
sc->sc_stats.ast_tx_htprotect++;
}
bf->bf_state.bfs_txflags = flags;
}
/*
* Update the frame duration given the currently selected rate.
*
* This also updates the frame duration value, so it will require
* a DMA flush.
*/
static void
ath_tx_calc_duration(struct ath_softc *sc, struct ath_buf *bf)
{
struct ieee80211_frame *wh;
uint8_t rix;
uint16_t flags;
int shortPreamble;
struct ath_hal *ah = sc->sc_ah;
const HAL_RATE_TABLE *rt = sc->sc_currates;
int isfrag = bf->bf_m->m_flags & M_FRAG;
flags = bf->bf_state.bfs_txflags;
rix = bf->bf_state.bfs_rc[0].rix;
shortPreamble = bf->bf_state.bfs_shpream;
wh = mtod(bf->bf_m, struct ieee80211_frame *);
/*
* Calculate duration. This logically belongs in the 802.11
* layer but it lacks sufficient information to calculate it.
*/
if ((flags & HAL_TXDESC_NOACK) == 0 &&
(wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) != IEEE80211_FC0_TYPE_CTL) {
u_int16_t dur;
if (shortPreamble)
dur = rt->info[rix].spAckDuration;
else
dur = rt->info[rix].lpAckDuration;
if (wh->i_fc[1] & IEEE80211_FC1_MORE_FRAG) {
dur += dur; /* additional SIFS+ACK */
/*
* Include the size of next fragment so NAV is
* updated properly. The last fragment uses only
* the ACK duration
*
* XXX TODO: ensure that the rate lookup for each
* fragment is the same as the rate used by the
* first fragment!
*/
Migrate ath(4) to now use if_transmit instead of the legacy if_start and if queue mechanism; also fix up (non-11n) TX fragment handling. This may result in a bit of a performance drop for now but I plan on debugging and resolving this at a later stage. Whilst here, fix the transmit path so fragment transmission works. The TX fragmentation handling is a bit more special. In order to correctly transmit TX fragments, there's a bunch of corner cases that need to be handled: * They must be transmitted back to back, in the same order.. * .. ie, you need to hold the TX lock whilst transmitting this set of fragments rather than interleaving it with other MSDUs destined to other nodes; * The length of the next fragment is required when transmitting, in order to correctly set the NAV field in the current frame to the length of the next frame; which requires .. * .. that we know the transmit duration of the next frame, which .. * .. requires us to set the rate of all fragments to the same length, or make the decision up-front, etc. To facilitate this, I've added a new ath_buf field to describe the length of the next fragment. This avoids having to keep the mbuf chain together. This used to work before my 11n TX path work because the ath_tx_start() routine would be handed a single mbuf with m_nextpkt pointing to the next frame, and that would be maintained all the way up to when the duration calculation was done. This doesn't hold true any longer - the actual queuing may occur at any point in the future (think ath_node TID software queuing) so this information needs to be maintained. Right now this does work for non-11n frames but it doesn't at all enforce the same rate control decision for all frames in the fragment. I plan on fixing this in a followup commit. RTS/CTS has the same issue, I'll look at fixing this in a subsequent commit. Finaly, 11n fragment support requires the driver to have fully decided what the rate scenario setup is - including 20/40MHz, short/long GI, STBC, LDPC, number of streams, etc. Right now that decision is (currently) made _after_ the NAV field value is updated. I'll fix all of this in subsequent commits. Tested: * AR5416, STA, transmitting 11abg fragments * AR5416, STA, 11n fragments work but the NAV field is incorrect for the reasons above. TODO: * It would be nice to be able to queue mbufs per-node and per-TID so we can only queue ath_buf entries when it's time to assemble frames to send to the hardware. But honestly, we should just do that level of software queue management in net80211 rather than ath(4), so I'm going to leave this alone for now. * More thorough AP, mesh and adhoc testing. * Ensure that net80211 doesn't hand us fragmented frames when A-MPDU has been negotiated, as we can't do software retransmission of fragments. * .. set CLRDMASK when transmitting fragments, just to ensure.
2013-05-26 22:23:39 +00:00
dur += ath_hal_computetxtime(ah,
rt,
bf->bf_nextfraglen,
rix, shortPreamble);
}
if (isfrag) {
/*
* Force hardware to use computed duration for next
* fragment by disabling multi-rate retry which updates
* duration based on the multi-rate duration table.
*/
bf->bf_state.bfs_ismrr = 0;
bf->bf_state.bfs_try0 = ATH_TXMGTTRY;
/* XXX update bfs_rc[0].try? */
}
/* Update the duration field itself */
*(u_int16_t *)wh->i_dur = htole16(dur);
}
}
static uint8_t
ath_tx_get_rtscts_rate(struct ath_hal *ah, const HAL_RATE_TABLE *rt,
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
int cix, int shortPreamble)
{
uint8_t ctsrate;
/*
* CTS transmit rate is derived from the transmit rate
* by looking in the h/w rate table. We must also factor
* in whether or not a short preamble is to be used.
*/
/* NB: cix is set above where RTS/CTS is enabled */
KASSERT(cix != 0xff, ("cix not setup"));
ctsrate = rt->info[cix].rateCode;
/* XXX this should only matter for legacy rates */
if (shortPreamble)
ctsrate |= rt->info[cix].shortPreamble;
return (ctsrate);
}
/*
* Calculate the RTS/CTS duration for legacy frames.
*/
static int
ath_tx_calc_ctsduration(struct ath_hal *ah, int rix, int cix,
int shortPreamble, int pktlen, const HAL_RATE_TABLE *rt,
int flags)
{
int ctsduration = 0;
/* This mustn't be called for HT modes */
if (rt->info[cix].phy == IEEE80211_T_HT) {
printf("%s: HT rate where it shouldn't be (0x%x)\n",
__func__, rt->info[cix].rateCode);
return (-1);
}
/*
* Compute the transmit duration based on the frame
* size and the size of an ACK frame. We call into the
* HAL to do the computation since it depends on the
* characteristics of the actual PHY being used.
*
* NB: CTS is assumed the same size as an ACK so we can
* use the precalculated ACK durations.
*/
if (shortPreamble) {
if (flags & HAL_TXDESC_RTSENA) /* SIFS + CTS */
ctsduration += rt->info[cix].spAckDuration;
ctsduration += ath_hal_computetxtime(ah,
rt, pktlen, rix, AH_TRUE);
if ((flags & HAL_TXDESC_NOACK) == 0) /* SIFS + ACK */
ctsduration += rt->info[rix].spAckDuration;
} else {
if (flags & HAL_TXDESC_RTSENA) /* SIFS + CTS */
ctsduration += rt->info[cix].lpAckDuration;
ctsduration += ath_hal_computetxtime(ah,
rt, pktlen, rix, AH_FALSE);
if ((flags & HAL_TXDESC_NOACK) == 0) /* SIFS + ACK */
ctsduration += rt->info[rix].lpAckDuration;
}
return (ctsduration);
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Update the given ath_buf with updated rts/cts setup and duration
* values.
*
* To support rate lookups for each software retry, the rts/cts rate
* and cts duration must be re-calculated.
*
* This function assumes the RTS/CTS flags have been set as needed;
* mrr has been disabled; and the rate control lookup has been done.
*
* XXX TODO: MRR need only be disabled for the pre-11n NICs.
* XXX The 11n NICs support per-rate RTS/CTS configuration.
*/
static void
ath_tx_set_rtscts(struct ath_softc *sc, struct ath_buf *bf)
{
uint16_t ctsduration = 0;
uint8_t ctsrate = 0;
uint8_t rix = bf->bf_state.bfs_rc[0].rix;
uint8_t cix = 0;
const HAL_RATE_TABLE *rt = sc->sc_currates;
/*
* No RTS/CTS enabled? Don't bother.
*/
if ((bf->bf_state.bfs_txflags &
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
(HAL_TXDESC_RTSENA | HAL_TXDESC_CTSENA)) == 0) {
/* XXX is this really needed? */
bf->bf_state.bfs_ctsrate = 0;
bf->bf_state.bfs_ctsduration = 0;
return;
}
/*
* If protection is enabled, use the protection rix control
* rate. Otherwise use the rate0 control rate.
*/
if (bf->bf_state.bfs_doprot)
rix = sc->sc_protrix;
else
rix = bf->bf_state.bfs_rc[0].rix;
/*
* If the raw path has hard-coded ctsrate0 to something,
* use it.
*/
if (bf->bf_state.bfs_ctsrate0 != 0)
cix = ath_tx_findrix(sc, bf->bf_state.bfs_ctsrate0);
else
/* Control rate from above */
cix = rt->info[rix].controlRate;
/* Calculate the rtscts rate for the given cix */
ctsrate = ath_tx_get_rtscts_rate(sc->sc_ah, rt, cix,
bf->bf_state.bfs_shpream);
/* The 11n chipsets do ctsduration calculations for you */
if (! ath_tx_is_11n(sc))
ctsduration = ath_tx_calc_ctsduration(sc->sc_ah, rix, cix,
bf->bf_state.bfs_shpream, bf->bf_state.bfs_pktlen,
rt, bf->bf_state.bfs_txflags);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Squirrel away in ath_buf */
bf->bf_state.bfs_ctsrate = ctsrate;
bf->bf_state.bfs_ctsduration = ctsduration;
/*
* Must disable multi-rate retry when using RTS/CTS.
*/
if (!sc->sc_mrrprot) {
bf->bf_state.bfs_ismrr = 0;
bf->bf_state.bfs_try0 =
bf->bf_state.bfs_rc[0].tries = ATH_TXMGTTRY; /* XXX ew */
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
/*
* Setup the descriptor chain for a normal or fast-frame
* frame.
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
*
* XXX TODO: extend to include the destination hardware QCU ID.
* Make sure that is correct. Make sure that when being added
* to the mcastq, the CABQ QCUID is set or things will get a bit
* odd.
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
*/
static void
ath_tx_setds(struct ath_softc *sc, struct ath_buf *bf)
{
struct ath_desc *ds = bf->bf_desc;
struct ath_hal *ah = sc->sc_ah;
if (bf->bf_state.bfs_txrate0 == 0)
DPRINTF(sc, ATH_DEBUG_XMIT,
"%s: bf=%p, txrate0=%d\n", __func__, bf, 0);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_hal_setuptxdesc(ah, ds
, bf->bf_state.bfs_pktlen /* packet length */
, bf->bf_state.bfs_hdrlen /* header length */
, bf->bf_state.bfs_atype /* Atheros packet type */
, bf->bf_state.bfs_txpower /* txpower */
, bf->bf_state.bfs_txrate0
, bf->bf_state.bfs_try0 /* series 0 rate/tries */
, bf->bf_state.bfs_keyix /* key cache index */
, bf->bf_state.bfs_txantenna /* antenna mode */
, bf->bf_state.bfs_txflags /* flags */
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
, bf->bf_state.bfs_ctsrate /* rts/cts rate */
, bf->bf_state.bfs_ctsduration /* rts/cts duration */
);
/*
* This will be overriden when the descriptor chain is written.
*/
bf->bf_lastds = ds;
bf->bf_last = bf;
/* Set rate control and descriptor chain for this frame */
ath_tx_set_ratectrl(sc, bf->bf_node, bf);
Convert the aggregate descriptor path over to use the same API as the non-aggregate path. I "cheated" by using some TX setup code in our HAL that isn't present in the atheros HAL (or Linux ath9k.) The old path for forming aggregates was: * setup the rate control in the first descriptor; * call chaintxdesc() on all the frames; * call setupfirsttxdesc() on the first descrpitor in the first frame; * call setuplasttxdesc() on the last descriptor in the last frame. The new path for forming aggregates looks like the non-aggregate path: * call setuptxdesc() on the first descriptor in the first frame; * setup the rate control in the first descriptor; * call filltxdesc() on each descriptor in the frame; * if it's an aggregate - call set11n_aggr_{first, middle, last} as appropriate (see the code for a description of what is "appropriate".) Now, this is done primarily for the AR9300 HAL - it doesn't implement the first set of aggregate functions. It just has the older methods and the "first/middle/last" aggregate methods. So, let's convert the code to use these. Note: the AR5416 HAL in FreeBSD had that code (from me, a while ago) and a previous commit brought it up to behave the same as the AR9300 HAL routines. There's some further tidyups to be done - specifically, avoid doing multiple calls to the 11n descriptor functions. I shouldn't call clr11n_aggr(), then set11n_aggr_middle(), then also set11n_aggr_first(). On (at least MIPS) the TX descriptors are in non-cachable memory and this will cause multiple slow writes. I'll debug/tidy that up in a future commit. Tested: * AR9280, STA * AR9280/AR9160, AP * AR9380, STA (using a local, closed source HAL, sorry!)
2012-11-06 06:19:11 +00:00
ath_tx_chaindesclist(sc, ds, bf, 0, 0, 0);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
/*
* Do a rate lookup.
*
* This performs a rate lookup for the given ath_buf only if it's required.
* Non-data frames and raw frames don't require it.
*
* This populates the primary and MRR entries; MRR values are
* then disabled later on if something requires it (eg RTS/CTS on
* pre-11n chipsets.
*
* This needs to be done before the RTS/CTS fields are calculated
* as they may depend upon the rate chosen.
*/
static void
ath_tx_do_ratelookup(struct ath_softc *sc, struct ath_buf *bf)
{
uint8_t rate, rix;
int try0;
if (! bf->bf_state.bfs_doratelookup)
return;
/* Get rid of any previous state */
bzero(bf->bf_state.bfs_rc, sizeof(bf->bf_state.bfs_rc));
ATH_NODE_LOCK(ATH_NODE(bf->bf_node));
ath_rate_findrate(sc, ATH_NODE(bf->bf_node), bf->bf_state.bfs_shpream,
bf->bf_state.bfs_pktlen, &rix, &try0, &rate);
/* In case MRR is disabled, make sure rc[0] is setup correctly */
bf->bf_state.bfs_rc[0].rix = rix;
bf->bf_state.bfs_rc[0].ratecode = rate;
bf->bf_state.bfs_rc[0].tries = try0;
if (bf->bf_state.bfs_ismrr && try0 != ATH_TXMAXTRY)
ath_rate_getxtxrates(sc, ATH_NODE(bf->bf_node), rix,
bf->bf_state.bfs_rc);
ATH_NODE_UNLOCK(ATH_NODE(bf->bf_node));
sc->sc_txrix = rix; /* for LED blinking */
sc->sc_lastdatarix = rix; /* for fast frames */
bf->bf_state.bfs_try0 = try0;
bf->bf_state.bfs_txrate0 = rate;
}
/*
* Update the CLRDMASK bit in the ath_buf if it needs to be set.
*/
static void
ath_tx_update_clrdmask(struct ath_softc *sc, struct ath_tid *tid,
struct ath_buf *bf)
{
struct ath_node *an = ATH_NODE(bf->bf_node);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
if (an->clrdmask == 1) {
bf->bf_state.bfs_txflags |= HAL_TXDESC_CLRDMASK;
an->clrdmask = 0;
}
}
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* Return whether this frame should be software queued or
* direct dispatched.
*
* When doing powersave, BAR frames should be queued but other management
* frames should be directly sent.
*
* When not doing powersave, stick BAR frames into the hardware queue
* so it goes out even though the queue is paused.
*
* For now, management frames are also software queued by default.
*/
static int
ath_tx_should_swq_frame(struct ath_softc *sc, struct ath_node *an,
struct mbuf *m0, int *queue_to_head)
{
struct ieee80211_node *ni = &an->an_node;
struct ieee80211_frame *wh;
uint8_t type, subtype;
wh = mtod(m0, struct ieee80211_frame *);
type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
(*queue_to_head) = 0;
/* If it's not in powersave - direct-dispatch BAR */
if ((ATH_NODE(ni)->an_is_powersave == 0)
&& type == IEEE80211_FC0_TYPE_CTL &&
subtype == IEEE80211_FC0_SUBTYPE_BAR) {
DPRINTF(sc, ATH_DEBUG_SW_TX,
"%s: BAR: TX'ing direct\n", __func__);
return (0);
} else if ((ATH_NODE(ni)->an_is_powersave == 1)
&& type == IEEE80211_FC0_TYPE_CTL &&
subtype == IEEE80211_FC0_SUBTYPE_BAR) {
/* BAR TX whilst asleep; queue */
DPRINTF(sc, ATH_DEBUG_SW_TX,
"%s: swq: TX'ing\n", __func__);
(*queue_to_head) = 1;
return (1);
} else if ((ATH_NODE(ni)->an_is_powersave == 1)
&& (type == IEEE80211_FC0_TYPE_MGT ||
type == IEEE80211_FC0_TYPE_CTL)) {
/*
* Other control/mgmt frame; bypass software queuing
* for now!
*/
DPRINTF(sc, ATH_DEBUG_XMIT,
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
"%s: %6D: Node is asleep; sending mgmt "
"(type=%d, subtype=%d)\n",
__func__, ni->ni_macaddr, ":", type, subtype);
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
return (0);
} else {
return (1);
}
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Transmit the given frame to the hardware.
*
* The frame must already be setup; rate control must already have
* been done.
*
* XXX since the TXQ lock is being held here (and I dislike holding
* it for this long when not doing software aggregation), later on
* break this function into "setup_normal" and "xmit_normal". The
* lock only needs to be held for the ath_tx_handoff call.
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
*
* XXX we don't update the leak count here - if we're doing
* direct frame dispatch, we need to be able to do it without
* decrementing the leak count (eg multicast queue frames.)
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
*/
static void
ath_tx_xmit_normal(struct ath_softc *sc, struct ath_txq *txq,
struct ath_buf *bf)
{
struct ath_node *an = ATH_NODE(bf->bf_node);
struct ath_tid *tid = &an->an_tid[bf->bf_state.bfs_tid];
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* For now, just enable CLRDMASK. ath_tx_xmit_normal() does
* set a completion handler however it doesn't (yet) properly
* handle the strict ordering requirements needed for normal,
* non-aggregate session frames.
*
* Once this is implemented, only set CLRDMASK like this for
* frames that must go out - eg management/raw frames.
*/
bf->bf_state.bfs_txflags |= HAL_TXDESC_CLRDMASK;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Setup the descriptor before handoff */
ath_tx_do_ratelookup(sc, bf);
ath_tx_calc_duration(sc, bf);
ath_tx_calc_protection(sc, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_set_rtscts(sc, bf);
ath_tx_rate_fill_rcflags(sc, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_setds(sc, bf);
/* Track per-TID hardware queue depth correctly */
tid->hwq_depth++;
/* Assign the completion handler */
bf->bf_comp = ath_tx_normal_comp;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Hand off to hardware */
ath_tx_handoff(sc, txq, bf);
}
2012-09-20 03:04:19 +00:00
/*
* Do the basic frame setup stuff that's required before the frame
* is added to a software queue.
*
* All frames get mostly the same treatment and it's done once.
* Retransmits fiddle with things like the rate control setup,
* setting the retransmit bit in the packet; doing relevant DMA/bus
* syncing and relinking it (back) into the hardware TX queue.
*
* Note that this may cause the mbuf to be reallocated, so
* m0 may not be valid.
*/
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
static int
ath_tx_normal_setup(struct ath_softc *sc, struct ieee80211_node *ni,
struct ath_buf *bf, struct mbuf *m0, struct ath_txq *txq)
{
struct ieee80211vap *vap = ni->ni_vap;
struct ath_hal *ah = sc->sc_ah;
struct ifnet *ifp = sc->sc_ifp;
struct ieee80211com *ic = ifp->if_l2com;
const struct chanAccParams *cap = &ic->ic_wme.wme_chanParams;
int error, iswep, ismcast, isfrag, ismrr;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
int keyix, hdrlen, pktlen, try0 = 0;
u_int8_t rix = 0, txrate = 0;
struct ath_desc *ds;
struct ieee80211_frame *wh;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
u_int subtype, flags;
HAL_PKT_TYPE atype;
const HAL_RATE_TABLE *rt;
HAL_BOOL shortPreamble;
struct ath_node *an;
u_int pri;
/*
* To ensure that both sequence numbers and the CCMP PN handling
* is "correct", make sure that the relevant TID queue is locked.
* Otherwise the CCMP PN and seqno may appear out of order, causing
* re-ordered frames to have out of order CCMP PN's, resulting
* in many, many frame drops.
*/
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
wh = mtod(m0, struct ieee80211_frame *);
iswep = wh->i_fc[1] & IEEE80211_FC1_WEP;
ismcast = IEEE80211_IS_MULTICAST(wh->i_addr1);
isfrag = m0->m_flags & M_FRAG;
hdrlen = ieee80211_anyhdrsize(wh);
/*
* Packet length must not include any
* pad bytes; deduct them here.
*/
pktlen = m0->m_pkthdr.len - (hdrlen & 3);
/* Handle encryption twiddling if needed */
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (! ath_tx_tag_crypto(sc, ni, m0, iswep, isfrag, &hdrlen,
&pktlen, &keyix)) {
ath_freetx(m0);
return EIO;
}
/* packet header may have moved, reset our local pointer */
wh = mtod(m0, struct ieee80211_frame *);
pktlen += IEEE80211_CRC_LEN;
/*
* Load the DMA map so any coalescing is done. This
* also calculates the number of descriptors we need.
*/
error = ath_tx_dmasetup(sc, bf, m0);
if (error != 0)
return error;
bf->bf_node = ni; /* NB: held reference */
m0 = bf->bf_m; /* NB: may have changed */
wh = mtod(m0, struct ieee80211_frame *);
/* setup descriptors */
ds = bf->bf_desc;
rt = sc->sc_currates;
KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
/*
* NB: the 802.11 layer marks whether or not we should
* use short preamble based on the current mode and
* negotiated parameters.
*/
if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
(ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_PREAMBLE)) {
shortPreamble = AH_TRUE;
sc->sc_stats.ast_tx_shortpre++;
} else {
shortPreamble = AH_FALSE;
}
an = ATH_NODE(ni);
//flags = HAL_TXDESC_CLRDMASK; /* XXX needed for crypto errs */
flags = 0;
ismrr = 0; /* default no multi-rate retry*/
pri = M_WME_GETAC(m0); /* honor classification */
/* XXX use txparams instead of fixed values */
/*
* Calculate Atheros packet type from IEEE80211 packet header,
* setup for rate calculations, and select h/w transmit queue.
*/
switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) {
case IEEE80211_FC0_TYPE_MGT:
subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
if (subtype == IEEE80211_FC0_SUBTYPE_BEACON)
atype = HAL_PKT_TYPE_BEACON;
else if (subtype == IEEE80211_FC0_SUBTYPE_PROBE_RESP)
atype = HAL_PKT_TYPE_PROBE_RESP;
else if (subtype == IEEE80211_FC0_SUBTYPE_ATIM)
atype = HAL_PKT_TYPE_ATIM;
else
atype = HAL_PKT_TYPE_NORMAL; /* XXX */
rix = an->an_mgmtrix;
txrate = rt->info[rix].rateCode;
if (shortPreamble)
txrate |= rt->info[rix].shortPreamble;
try0 = ATH_TXMGTTRY;
flags |= HAL_TXDESC_INTREQ; /* force interrupt */
break;
case IEEE80211_FC0_TYPE_CTL:
atype = HAL_PKT_TYPE_PSPOLL; /* stop setting of duration */
rix = an->an_mgmtrix;
txrate = rt->info[rix].rateCode;
if (shortPreamble)
txrate |= rt->info[rix].shortPreamble;
try0 = ATH_TXMGTTRY;
flags |= HAL_TXDESC_INTREQ; /* force interrupt */
break;
case IEEE80211_FC0_TYPE_DATA:
atype = HAL_PKT_TYPE_NORMAL; /* default */
/*
* Data frames: multicast frames go out at a fixed rate,
* EAPOL frames use the mgmt frame rate; otherwise consult
* the rate control module for the rate to use.
*/
if (ismcast) {
rix = an->an_mcastrix;
txrate = rt->info[rix].rateCode;
if (shortPreamble)
txrate |= rt->info[rix].shortPreamble;
try0 = 1;
} else if (m0->m_flags & M_EAPOL) {
/* XXX? maybe always use long preamble? */
rix = an->an_mgmtrix;
txrate = rt->info[rix].rateCode;
if (shortPreamble)
txrate |= rt->info[rix].shortPreamble;
try0 = ATH_TXMAXTRY; /* XXX?too many? */
} else {
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Do rate lookup on each TX, rather than using
* the hard-coded TX information decided here.
*/
ismrr = 1;
bf->bf_state.bfs_doratelookup = 1;
}
if (cap->cap_wmeParams[pri].wmep_noackPolicy)
flags |= HAL_TXDESC_NOACK;
break;
default:
if_printf(ifp, "bogus frame type 0x%x (%s)\n",
wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK, __func__);
/* XXX statistic */
/* XXX free tx dmamap */
ath_freetx(m0);
return EIO;
}
/*
* There are two known scenarios where the frame AC doesn't match
* what the destination TXQ is.
*
* + non-QoS frames (eg management?) that the net80211 stack has
* assigned a higher AC to, but since it's a non-QoS TID, it's
* being thrown into TID 16. TID 16 gets the AC_BE queue.
* It's quite possible that management frames should just be
* direct dispatched to hardware rather than go via the software
* queue; that should be investigated in the future. There are
* some specific scenarios where this doesn't make sense, mostly
* surrounding ADDBA request/response - hence why that is special
* cased.
*
* + Multicast frames going into the VAP mcast queue. That shows up
* as "TXQ 11".
*
* This driver should eventually support separate TID and TXQ locking,
* allowing for arbitrary AC frames to appear on arbitrary software
* queues, being queued to the "correct" hardware queue when needed.
*/
#if 0
if (txq != sc->sc_ac2q[pri]) {
DPRINTF(sc, ATH_DEBUG_XMIT,
"%s: txq=%p (%d), pri=%d, pri txq=%p (%d)\n",
__func__,
txq,
txq->axq_qnum,
pri,
sc->sc_ac2q[pri],
sc->sc_ac2q[pri]->axq_qnum);
}
#endif
/*
* Calculate miscellaneous flags.
*/
if (ismcast) {
flags |= HAL_TXDESC_NOACK; /* no ack on broad/multicast */
} else if (pktlen > vap->iv_rtsthreshold &&
(ni->ni_ath_flags & IEEE80211_NODE_FF) == 0) {
flags |= HAL_TXDESC_RTSENA; /* RTS based on frame length */
sc->sc_stats.ast_tx_rts++;
}
if (flags & HAL_TXDESC_NOACK) /* NB: avoid double counting */
sc->sc_stats.ast_tx_noack++;
#ifdef IEEE80211_SUPPORT_TDMA
if (sc->sc_tdma && (flags & HAL_TXDESC_NOACK) == 0) {
DPRINTF(sc, ATH_DEBUG_TDMA,
"%s: discard frame, ACK required w/ TDMA\n", __func__);
sc->sc_stats.ast_tdma_ack++;
/* XXX free tx dmamap */
ath_freetx(m0);
return EIO;
}
#endif
/*
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
* Determine if a tx interrupt should be generated for
* this descriptor. We take a tx interrupt to reap
* descriptors when the h/w hits an EOL condition or
* when the descriptor is specifically marked to generate
* an interrupt. We periodically mark descriptors in this
* way to insure timely replenishing of the supply needed
* for sending frames. Defering interrupts reduces system
* load and potentially allows more concurrent work to be
* done but if done to aggressively can cause senders to
* backup.
*
* NB: use >= to deal with sc_txintrperiod changing
* dynamically through sysctl.
*/
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (flags & HAL_TXDESC_INTREQ) {
txq->axq_intrcnt = 0;
} else if (++txq->axq_intrcnt >= sc->sc_txintrperiod) {
flags |= HAL_TXDESC_INTREQ;
txq->axq_intrcnt = 0;
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* This point forward is actual TX bits */
/*
* At this point we are committed to sending the frame
* and we don't need to look at m_nextpkt; clear it in
* case this frame is part of frag chain.
*/
m0->m_nextpkt = NULL;
if (IFF_DUMPPKTS(sc, ATH_DEBUG_XMIT))
ieee80211_dump_pkt(ic, mtod(m0, const uint8_t *), m0->m_len,
sc->sc_hwmap[rix].ieeerate, -1);
if (ieee80211_radiotap_active_vap(vap)) {
u_int64_t tsf = ath_hal_gettsf64(ah);
sc->sc_tx_th.wt_tsf = htole64(tsf);
sc->sc_tx_th.wt_flags = sc->sc_hwmap[rix].txflags;
if (iswep)
sc->sc_tx_th.wt_flags |= IEEE80211_RADIOTAP_F_WEP;
if (isfrag)
sc->sc_tx_th.wt_flags |= IEEE80211_RADIOTAP_F_FRAG;
sc->sc_tx_th.wt_rate = sc->sc_hwmap[rix].ieeerate;
sc->sc_tx_th.wt_txpower = ieee80211_get_node_txpower(ni);
sc->sc_tx_th.wt_antenna = sc->sc_txantenna;
ieee80211_radiotap_tx(vap, m0);
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Blank the legacy rate array */
bzero(&bf->bf_state.bfs_rc, sizeof(bf->bf_state.bfs_rc));
/*
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
* ath_buf_set_rate needs at least one rate/try to setup
* the rate scenario.
*/
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
bf->bf_state.bfs_rc[0].rix = rix;
bf->bf_state.bfs_rc[0].tries = try0;
bf->bf_state.bfs_rc[0].ratecode = txrate;
/* Store the decided rate index values away */
bf->bf_state.bfs_pktlen = pktlen;
bf->bf_state.bfs_hdrlen = hdrlen;
bf->bf_state.bfs_atype = atype;
bf->bf_state.bfs_txpower = ieee80211_get_node_txpower(ni);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
bf->bf_state.bfs_txrate0 = txrate;
bf->bf_state.bfs_try0 = try0;
bf->bf_state.bfs_keyix = keyix;
bf->bf_state.bfs_txantenna = sc->sc_txantenna;
bf->bf_state.bfs_txflags = flags;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
bf->bf_state.bfs_shpream = shortPreamble;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* XXX this should be done in ath_tx_setrate() */
bf->bf_state.bfs_ctsrate0 = 0; /* ie, no hard-coded ctsrate */
bf->bf_state.bfs_ctsrate = 0; /* calculated later */
bf->bf_state.bfs_ctsduration = 0;
bf->bf_state.bfs_ismrr = ismrr;
return 0;
}
/*
* Queue a frame to the hardware or software queue.
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
*
* This can be called by the net80211 code.
*
* XXX what about locking? Or, push the seqno assign into the
* XXX aggregate scheduler so its serialised?
*
* XXX When sending management frames via ath_raw_xmit(),
* should CLRDMASK be set unconditionally?
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
*/
int
ath_tx_start(struct ath_softc *sc, struct ieee80211_node *ni,
struct ath_buf *bf, struct mbuf *m0)
{
struct ieee80211vap *vap = ni->ni_vap;
struct ath_vap *avp = ATH_VAP(vap);
int r = 0;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
u_int pri;
int tid;
struct ath_txq *txq;
int ismcast;
const struct ieee80211_frame *wh;
int is_ampdu, is_ampdu_tx, is_ampdu_pending;
ieee80211_seq seqno;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
uint8_t type, subtype;
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
int queue_to_head;
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
/*
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
* Determine the target hardware queue.
*
* For multicast frames, the txq gets overridden appropriately
* depending upon the state of PS.
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
*
* For any other frame, we do a TID/QoS lookup inside the frame
* to see what the TID should be. If it's a non-QoS frame, the
* AC and TID are overridden. The TID/TXQ code assumes the
* TID is on a predictable hardware TXQ, so we don't support
* having a node TID queued to multiple hardware TXQs.
* This may change in the future but would require some locking
* fudgery.
*/
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
pri = ath_tx_getac(sc, m0);
tid = ath_tx_gettid(sc, m0);
txq = sc->sc_ac2q[pri];
wh = mtod(m0, struct ieee80211_frame *);
ismcast = IEEE80211_IS_MULTICAST(wh->i_addr1);
type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
/*
* Enforce how deep the multicast queue can grow.
*
* XXX duplicated in ath_raw_xmit().
*/
if (IEEE80211_IS_MULTICAST(wh->i_addr1)) {
Implement the replacement EDMA FIFO code. (Yes, the previous code temporarily broke EDMA TX. I'm sorry; I should've actually setup ATH_BUF_FIFOEND on frames so txq->axq_fifo_depth was cleared!) This code implements a whole bunch of sorely needed EDMA TX improvements along with CABQ TX support. The specifics: * When filling/refilling the FIFO, use the new TXQ staging queue for FIFO frames * Tag frames with ATH_BUF_FIFOPTR and ATH_BUF_FIFOEND correctly. For now the non-CABQ transmit path pushes one frame into the TXQ staging queue without setting up the intermediary link pointers to chain them together, so draining frames from the txq staging queue to the FIFO queue occurs AMPDU / MPDU at a time. * In the CABQ case, manually tag the list with ATH_BUF_FIFOPTR and ATH_BUF_FIFOEND so a chain of frames is pushed into the FIFO at once. * Now that frames are in a FIFO pending queue, we can top up the FIFO after completing a single frame. This means we can keep it filled rather than waiting for it drain and _then_ adding more frames. * The EDMA restart routine now walks the FIFO queue in the TXQ rather than the pending queue and re-initialises the FIFO with that. * When restarting EDMA, we may have partially completed sending a list. So stamp the first frame that we see in a list with ATH_BUF_FIFOPTR and push _that_ into the hardware. * When completing frames, only check those on the FIFO queue. We should never ever queue frames from the pending queue direct to the hardware, so there's no point in checking. * Until I figure out what's going on, make sure if the TXSTATUS for an empty queue pops up, complain loudly and continue. This will stop the panics that people are seeing. I'll add some code later which will assist in ensuring I'm populating each descriptor with the correct queue ID. * When considering whether to queue frames to the hardware queue directly or software queue frames, make sure the depth of the FIFO is taken into account now. * When completing frames, tag them with ATH_BUF_BUSY if they're not the final frame in a FIFO list. The same holding descriptor behaviour is required when handling descriptors linked together with a link pointer as the hardware will re-read the previous descriptor to refresh the link pointer before contiuning. * .. and if we complete the FIFO list (ie, the buffer has ATH_BUF_FIFOEND set), then we don't need the holding buffer any longer. Thus, free it. Tested: * AR9380/AR9580, STA and hostap * AR9280, STA/hostap TODO: * I don't yet trust that the EDMA restart routine is totally correct in all circumstances. I'll continue to thrash this out under heavy multiple-TXQ traffic load and fix whatever pops up.
2013-03-26 20:04:45 +00:00
if (sc->sc_cabq->axq_depth + sc->sc_cabq->fifo.axq_depth
> sc->sc_txq_mcastq_maxdepth) {
sc->sc_stats.ast_tx_mcastq_overflow++;
m_freem(m0);
2013-05-07 07:44:07 +00:00
return (ENOBUFS);
}
}
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* Enforce how deep the unicast queue can grow.
*
* If the node is in power save then we don't want
* the software queue to grow too deep, or a node may
* end up consuming all of the ath_buf entries.
*
* For now, only do this for DATA frames.
*
* We will want to cap how many management/control
* frames get punted to the software queue so it doesn't
* fill up. But the correct solution isn't yet obvious.
* In any case, this check should at least let frames pass
* that we are direct-dispatching.
*
* XXX TODO: duplicate this to the raw xmit path!
*/
if (type == IEEE80211_FC0_TYPE_DATA &&
ATH_NODE(ni)->an_is_powersave &&
ATH_NODE(ni)->an_swq_depth >
sc->sc_txq_node_psq_maxdepth) {
sc->sc_stats.ast_tx_node_psq_overflow++;
m_freem(m0);
return (ENOBUFS);
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* A-MPDU TX */
is_ampdu_tx = ath_tx_ampdu_running(sc, ATH_NODE(ni), tid);
is_ampdu_pending = ath_tx_ampdu_pending(sc, ATH_NODE(ni), tid);
is_ampdu = is_ampdu_tx | is_ampdu_pending;
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: tid=%d, ac=%d, is_ampdu=%d\n",
__func__, tid, pri, is_ampdu);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
/* Set local packet state, used to queue packets to hardware */
bf->bf_state.bfs_tid = tid;
bf->bf_state.bfs_tx_queue = txq->axq_qnum;
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
bf->bf_state.bfs_pri = pri;
Overhaul the TXQ locking (again!) as part of some beacon/cabq timing related issues. Moving the TX locking under one lock made things easier to progress on but it had one important side-effect - it increased the latency when handling CABQ setup when sending beacons. This commit introduces a bunch of new changes and a few unrelated changs that are just easier to lump in here. The aim is to have the CABQ locking separate from other locking. The CABQ transmit path in the beacon process thus doesn't have to grab the general TX lock, reducing lock contention/latency and making it more likely that we'll make the beacon TX timing. The second half of this commit is the CABQ related setup changes needed for sane looking EDMA CABQ support. Right now the EDMA TX code naively assumes that only one frame (MPDU or A-MPDU) is being pushed into each FIFO slot. For the CABQ this isn't true - a whole list of frames is being pushed in - and thus CABQ handling breaks very quickly. The aim here is to setup the CABQ list and then push _that list_ to the hardware for transmission. I can then extend the EDMA TX code to stamp that list as being "one" FIFO entry (likely by tagging the last buffer in that list as "FIFO END") so the EDMA TX completion code correctly tracks things. Major: * Migrate the per-TXQ add/removal locking back to per-TXQ, rather than a single lock. * Leave the software queue side of things under the ATH_TX_LOCK lock, (continuing) to serialise things as they are. * Add a new function which is called whenever there's a beacon miss, to print out some debugging. This is primarily designed to help me figure out if the beacon miss events are due to a noisy environment, issues with the PHY/MAC, or other. * Move the CABQ setup/enable to occur _after_ all the VAPs have been looked at. This means that for multiple VAPS in bursted mode, the CABQ gets primed once all VAPs are checked, rather than being primed on the first VAP and then having frames appended after this. Minor: * Add a (disabled) twiddle to let me enable/disable cabq traffic. It's primarily there to let me easily debug what's going on with beacon and CABQ setup/traffic; there's some DMA engine hangs which I'm finally trying to trace down. * Clear bf_next when flushing frames; it should quieten some warnings that show up when a node goes away. Tested: * AR9280, STA/hostap, up to 4 vaps (staggered) * AR5416, STA/hostap, up to 4 vaps (staggered) TODO: * (Lots) more AR9380 and later testing, as I may have missed something here. * Leverage this to fix CABQ hanling for AR9380 and later chips. * Force bursted beaconing on the chips that default to staggered beacons and ensure the CABQ stuff is all sane (eg, the MORE bits that aren't being correctly set when chaining descriptors.)
2013-03-24 00:03:12 +00:00
#if 1
/*
* When servicing one or more stations in power-save mode
* (or) if there is some mcast data waiting on the mcast
* queue (to prevent out of order delivery) multicast frames
* must be bufferd until after the beacon.
*
* TODO: we should lock the mcastq before we check the length.
*/
Overhaul the TXQ locking (again!) as part of some beacon/cabq timing related issues. Moving the TX locking under one lock made things easier to progress on but it had one important side-effect - it increased the latency when handling CABQ setup when sending beacons. This commit introduces a bunch of new changes and a few unrelated changs that are just easier to lump in here. The aim is to have the CABQ locking separate from other locking. The CABQ transmit path in the beacon process thus doesn't have to grab the general TX lock, reducing lock contention/latency and making it more likely that we'll make the beacon TX timing. The second half of this commit is the CABQ related setup changes needed for sane looking EDMA CABQ support. Right now the EDMA TX code naively assumes that only one frame (MPDU or A-MPDU) is being pushed into each FIFO slot. For the CABQ this isn't true - a whole list of frames is being pushed in - and thus CABQ handling breaks very quickly. The aim here is to setup the CABQ list and then push _that list_ to the hardware for transmission. I can then extend the EDMA TX code to stamp that list as being "one" FIFO entry (likely by tagging the last buffer in that list as "FIFO END") so the EDMA TX completion code correctly tracks things. Major: * Migrate the per-TXQ add/removal locking back to per-TXQ, rather than a single lock. * Leave the software queue side of things under the ATH_TX_LOCK lock, (continuing) to serialise things as they are. * Add a new function which is called whenever there's a beacon miss, to print out some debugging. This is primarily designed to help me figure out if the beacon miss events are due to a noisy environment, issues with the PHY/MAC, or other. * Move the CABQ setup/enable to occur _after_ all the VAPs have been looked at. This means that for multiple VAPS in bursted mode, the CABQ gets primed once all VAPs are checked, rather than being primed on the first VAP and then having frames appended after this. Minor: * Add a (disabled) twiddle to let me enable/disable cabq traffic. It's primarily there to let me easily debug what's going on with beacon and CABQ setup/traffic; there's some DMA engine hangs which I'm finally trying to trace down. * Clear bf_next when flushing frames; it should quieten some warnings that show up when a node goes away. Tested: * AR9280, STA/hostap, up to 4 vaps (staggered) * AR5416, STA/hostap, up to 4 vaps (staggered) TODO: * (Lots) more AR9380 and later testing, as I may have missed something here. * Leverage this to fix CABQ hanling for AR9380 and later chips. * Force bursted beaconing on the chips that default to staggered beacons and ensure the CABQ stuff is all sane (eg, the MORE bits that aren't being correctly set when chaining descriptors.)
2013-03-24 00:03:12 +00:00
if (sc->sc_cabq_enable && ismcast && (vap->iv_ps_sta || avp->av_mcastq.axq_depth)) {
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
txq = &avp->av_mcastq;
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
/*
* Mark the frame as eventually belonging on the CAB
* queue, so the descriptor setup functions will
* correctly initialise the descriptor 'qcuId' field.
*/
bf->bf_state.bfs_tx_queue = sc->sc_cabq->axq_qnum;
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
}
Overhaul the TXQ locking (again!) as part of some beacon/cabq timing related issues. Moving the TX locking under one lock made things easier to progress on but it had one important side-effect - it increased the latency when handling CABQ setup when sending beacons. This commit introduces a bunch of new changes and a few unrelated changs that are just easier to lump in here. The aim is to have the CABQ locking separate from other locking. The CABQ transmit path in the beacon process thus doesn't have to grab the general TX lock, reducing lock contention/latency and making it more likely that we'll make the beacon TX timing. The second half of this commit is the CABQ related setup changes needed for sane looking EDMA CABQ support. Right now the EDMA TX code naively assumes that only one frame (MPDU or A-MPDU) is being pushed into each FIFO slot. For the CABQ this isn't true - a whole list of frames is being pushed in - and thus CABQ handling breaks very quickly. The aim here is to setup the CABQ list and then push _that list_ to the hardware for transmission. I can then extend the EDMA TX code to stamp that list as being "one" FIFO entry (likely by tagging the last buffer in that list as "FIFO END") so the EDMA TX completion code correctly tracks things. Major: * Migrate the per-TXQ add/removal locking back to per-TXQ, rather than a single lock. * Leave the software queue side of things under the ATH_TX_LOCK lock, (continuing) to serialise things as they are. * Add a new function which is called whenever there's a beacon miss, to print out some debugging. This is primarily designed to help me figure out if the beacon miss events are due to a noisy environment, issues with the PHY/MAC, or other. * Move the CABQ setup/enable to occur _after_ all the VAPs have been looked at. This means that for multiple VAPS in bursted mode, the CABQ gets primed once all VAPs are checked, rather than being primed on the first VAP and then having frames appended after this. Minor: * Add a (disabled) twiddle to let me enable/disable cabq traffic. It's primarily there to let me easily debug what's going on with beacon and CABQ setup/traffic; there's some DMA engine hangs which I'm finally trying to trace down. * Clear bf_next when flushing frames; it should quieten some warnings that show up when a node goes away. Tested: * AR9280, STA/hostap, up to 4 vaps (staggered) * AR5416, STA/hostap, up to 4 vaps (staggered) TODO: * (Lots) more AR9380 and later testing, as I may have missed something here. * Leverage this to fix CABQ hanling for AR9380 and later chips. * Force bursted beaconing on the chips that default to staggered beacons and ensure the CABQ stuff is all sane (eg, the MORE bits that aren't being correctly set when chaining descriptors.)
2013-03-24 00:03:12 +00:00
#endif
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Do the generic frame setup */
/* XXX should just bzero the bf_state? */
bf->bf_state.bfs_dobaw = 0;
/* A-MPDU TX? Manually set sequence number */
/*
* Don't do it whilst pending; the net80211 layer still
* assigns them.
*/
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (is_ampdu_tx) {
/*
* Always call; this function will
* handle making sure that null data frames
* don't get a sequence number from the current
* TID and thus mess with the BAW.
*/
seqno = ath_tx_tid_seqno_assign(sc, ni, bf, m0);
/*
* Don't add QoS NULL frames to the BAW.
*/
if (IEEE80211_QOS_HAS_SEQ(wh) &&
subtype != IEEE80211_FC0_SUBTYPE_QOS_NULL) {
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
bf->bf_state.bfs_dobaw = 1;
}
}
/*
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
* If needed, the sequence number has been assigned.
* Squirrel it away somewhere easy to get to.
*/
bf->bf_state.bfs_seqno = M_SEQNO_GET(m0) << IEEE80211_SEQ_SEQ_SHIFT;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Is ampdu pending? fetch the seqno and print it out */
if (is_ampdu_pending)
DPRINTF(sc, ATH_DEBUG_SW_TX,
"%s: tid %d: ampdu pending, seqno %d\n",
__func__, tid, M_SEQNO_GET(m0));
/* This also sets up the DMA map */
r = ath_tx_normal_setup(sc, ni, bf, m0, txq);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (r != 0)
goto done;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* At this point m0 could have changed! */
m0 = bf->bf_m;
#if 1
/*
* If it's a multicast frame, do a direct-dispatch to the
* destination hardware queue. Don't bother software
* queuing it.
*/
/*
* If it's a BAR frame, do a direct dispatch to the
* destination hardware queue. Don't bother software
* queuing it, as the TID will now be paused.
* Sending a BAR frame can occur from the net80211 txa timer
* (ie, retries) or from the ath txtask (completion call.)
* It queues directly to hardware because the TID is paused
* at this point (and won't be unpaused until the BAR has
* either been TXed successfully or max retries has been
* reached.)
*/
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* Until things are better debugged - if this node is asleep
* and we're sending it a non-BAR frame, direct dispatch it.
* Why? Because we need to figure out what's actually being
* sent - eg, during reassociation/reauthentication after
* the node (last) disappeared whilst asleep, the driver should
* have unpaused/unsleep'ed the node. So until that is
* sorted out, use this workaround.
*/
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (txq == &avp->av_mcastq) {
DPRINTF(sc, ATH_DEBUG_SW_TX,
Delay sequence number allocation for A-MPDU until just before the frame is queued to the hardware. Because multiple concurrent paths can execute ath_start(), multiple concurrent paths can push frames into the software/hardware TX queue and since preemption/interrupting can occur, there's the possibility that a gap in time will occur between allocating the sequence number and queuing it to the hardware. Because of this, it's possible that a thread will have allocated a sequence number and then be preempted by another thread doing the same. If the second thread sneaks the frame into the BAW, the (earlier) sequence number of the first frame will be now outside the BAW and will result in the frame being constantly re-added to the tail of the queue. There it will live until the sequence numbers cycle around again. This also creates a hole in the RX BAW tracking which can also cause issues. This patch delays the sequence number allocation to occur only just before the frame is going to be added to the BAW. I've been wanting to do this anyway as part of a general code tidyup but I've not gotten around to it. This fixes the PR. However, it still makes it quite difficult to try and ensure in-order queuing and dequeuing of frames. Since multiple copies of ath_start() can be run at the same time (eg one TXing process thread, one TX completion task/one RX task) the driver may end up having frames dequeued and pushed into the hardware slightly/occasionally out of order. And, to make matters more annoying, net80211 may have the same behaviour - in the non-aggregation case, the TX code allocates sequence numbers before it's thrown to the driver. I'll open another PR to investigate this and potentially introduce some kind of final-pass TX serialisation before frames are thrown to the hardware. It's also very likely worthwhile adding some debugging code into ath(4) and net80211 to catch when/if this does occur. PR: kern/166190
2012-03-20 04:50:25 +00:00
"%s: bf=%p: mcastq: TX'ing\n", __func__, bf);
bf->bf_state.bfs_txflags |= HAL_TXDESC_CLRDMASK;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_xmit_normal(sc, txq, bf);
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
} else if (ath_tx_should_swq_frame(sc, ATH_NODE(ni), m0,
&queue_to_head)) {
ath_tx_swq(sc, ni, txq, queue_to_head, bf);
} else {
bf->bf_state.bfs_txflags |= HAL_TXDESC_CLRDMASK;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_xmit_normal(sc, txq, bf);
}
#else
/*
* For now, since there's no software queue,
* direct-dispatch to the hardware.
*/
bf->bf_state.bfs_txflags |= HAL_TXDESC_CLRDMASK;
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* Update the current leak count if
* we're leaking frames; and set the
* MORE flag as appropriate.
*/
ath_tx_leak_count_update(sc, tid, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_xmit_normal(sc, txq, bf);
#endif
done:
return 0;
}
static int
ath_tx_raw_start(struct ath_softc *sc, struct ieee80211_node *ni,
struct ath_buf *bf, struct mbuf *m0,
const struct ieee80211_bpf_params *params)
{
struct ifnet *ifp = sc->sc_ifp;
struct ieee80211com *ic = ifp->if_l2com;
struct ath_hal *ah = sc->sc_ah;
struct ieee80211vap *vap = ni->ni_vap;
int error, ismcast, ismrr;
int keyix, hdrlen, pktlen, try0, txantenna;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
u_int8_t rix, txrate;
struct ieee80211_frame *wh;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
u_int flags;
HAL_PKT_TYPE atype;
const HAL_RATE_TABLE *rt;
struct ath_desc *ds;
u_int pri;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
int o_tid = -1;
int do_override;
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
uint8_t type, subtype;
int queue_to_head;
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
wh = mtod(m0, struct ieee80211_frame *);
ismcast = IEEE80211_IS_MULTICAST(wh->i_addr1);
hdrlen = ieee80211_anyhdrsize(wh);
/*
* Packet length must not include any
* pad bytes; deduct them here.
*/
/* XXX honor IEEE80211_BPF_DATAPAD */
pktlen = m0->m_pkthdr.len - (hdrlen & 3) + IEEE80211_CRC_LEN;
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
ATH_KTR(sc, ATH_KTR_TX, 2,
"ath_tx_raw_start: ni=%p, bf=%p, raw", ni, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: ismcast=%d\n",
__func__, ismcast);
pri = params->ibp_pri & 3;
/* Override pri if the frame isn't a QoS one */
if (! IEEE80211_QOS_HAS_SEQ(wh))
pri = ath_tx_getac(sc, m0);
/* XXX If it's an ADDBA, override the correct queue */
do_override = ath_tx_action_frame_override_queue(sc, ni, m0, &o_tid);
/* Map ADDBA to the correct priority */
if (do_override) {
#if 0
DPRINTF(sc, ATH_DEBUG_XMIT,
"%s: overriding tid %d pri %d -> %d\n",
__func__, o_tid, pri, TID_TO_WME_AC(o_tid));
#endif
pri = TID_TO_WME_AC(o_tid);
}
/* Handle encryption twiddling if needed */
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (! ath_tx_tag_crypto(sc, ni,
m0, params->ibp_flags & IEEE80211_BPF_CRYPTO, 0,
&hdrlen, &pktlen, &keyix)) {
ath_freetx(m0);
return EIO;
}
/* packet header may have moved, reset our local pointer */
wh = mtod(m0, struct ieee80211_frame *);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Do the generic frame setup */
/* XXX should just bzero the bf_state? */
bf->bf_state.bfs_dobaw = 0;
error = ath_tx_dmasetup(sc, bf, m0);
if (error != 0)
return error;
m0 = bf->bf_m; /* NB: may have changed */
wh = mtod(m0, struct ieee80211_frame *);
bf->bf_node = ni; /* NB: held reference */
/* Always enable CLRDMASK for raw frames for now.. */
flags = HAL_TXDESC_CLRDMASK; /* XXX needed for crypto errs */
flags |= HAL_TXDESC_INTREQ; /* force interrupt */
if (params->ibp_flags & IEEE80211_BPF_RTS)
flags |= HAL_TXDESC_RTSENA;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
else if (params->ibp_flags & IEEE80211_BPF_CTS) {
/* XXX assume 11g/11n protection? */
bf->bf_state.bfs_doprot = 1;
flags |= HAL_TXDESC_CTSENA;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
/* XXX leave ismcast to injector? */
if ((params->ibp_flags & IEEE80211_BPF_NOACK) || ismcast)
flags |= HAL_TXDESC_NOACK;
rt = sc->sc_currates;
KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
rix = ath_tx_findrix(sc, params->ibp_rate0);
txrate = rt->info[rix].rateCode;
if (params->ibp_flags & IEEE80211_BPF_SHORTPRE)
txrate |= rt->info[rix].shortPreamble;
sc->sc_txrix = rix;
try0 = params->ibp_try0;
ismrr = (params->ibp_try1 != 0);
txantenna = params->ibp_pri >> 2;
if (txantenna == 0) /* XXX? */
txantenna = sc->sc_txantenna;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Since ctsrate is fixed, store it away for later
* use when the descriptor fields are being set.
*/
if (flags & (HAL_TXDESC_RTSENA|HAL_TXDESC_CTSENA))
bf->bf_state.bfs_ctsrate0 = params->ibp_ctsrate;
/*
* NB: we mark all packets as type PSPOLL so the h/w won't
* set the sequence number, duration, etc.
*/
atype = HAL_PKT_TYPE_PSPOLL;
if (IFF_DUMPPKTS(sc, ATH_DEBUG_XMIT))
ieee80211_dump_pkt(ic, mtod(m0, caddr_t), m0->m_len,
sc->sc_hwmap[rix].ieeerate, -1);
if (ieee80211_radiotap_active_vap(vap)) {
u_int64_t tsf = ath_hal_gettsf64(ah);
sc->sc_tx_th.wt_tsf = htole64(tsf);
sc->sc_tx_th.wt_flags = sc->sc_hwmap[rix].txflags;
if (wh->i_fc[1] & IEEE80211_FC1_WEP)
sc->sc_tx_th.wt_flags |= IEEE80211_RADIOTAP_F_WEP;
if (m0->m_flags & M_FRAG)
sc->sc_tx_th.wt_flags |= IEEE80211_RADIOTAP_F_FRAG;
sc->sc_tx_th.wt_rate = sc->sc_hwmap[rix].ieeerate;
sc->sc_tx_th.wt_txpower = MIN(params->ibp_power,
ieee80211_get_node_txpower(ni));
sc->sc_tx_th.wt_antenna = sc->sc_txantenna;
ieee80211_radiotap_tx(vap, m0);
}
/*
* Formulate first tx descriptor with tx controls.
*/
ds = bf->bf_desc;
/* XXX check return value? */
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Store the decided rate index values away */
bf->bf_state.bfs_pktlen = pktlen;
bf->bf_state.bfs_hdrlen = hdrlen;
bf->bf_state.bfs_atype = atype;
bf->bf_state.bfs_txpower = MIN(params->ibp_power,
ieee80211_get_node_txpower(ni));
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
bf->bf_state.bfs_txrate0 = txrate;
bf->bf_state.bfs_try0 = try0;
bf->bf_state.bfs_keyix = keyix;
bf->bf_state.bfs_txantenna = txantenna;
bf->bf_state.bfs_txflags = flags;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
bf->bf_state.bfs_shpream =
!! (params->ibp_flags & IEEE80211_BPF_SHORTPRE);
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
/* Set local packet state, used to queue packets to hardware */
bf->bf_state.bfs_tid = WME_AC_TO_TID(pri);
bf->bf_state.bfs_tx_queue = sc->sc_ac2q[pri]->axq_qnum;
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
bf->bf_state.bfs_pri = pri;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* XXX this should be done in ath_tx_setrate() */
bf->bf_state.bfs_ctsrate = 0;
bf->bf_state.bfs_ctsduration = 0;
bf->bf_state.bfs_ismrr = ismrr;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Blank the legacy rate array */
bzero(&bf->bf_state.bfs_rc, sizeof(bf->bf_state.bfs_rc));
bf->bf_state.bfs_rc[0].rix =
ath_tx_findrix(sc, params->ibp_rate0);
bf->bf_state.bfs_rc[0].tries = try0;
bf->bf_state.bfs_rc[0].ratecode = txrate;
if (ismrr) {
int rix;
rix = ath_tx_findrix(sc, params->ibp_rate1);
bf->bf_state.bfs_rc[1].rix = rix;
bf->bf_state.bfs_rc[1].tries = params->ibp_try1;
rix = ath_tx_findrix(sc, params->ibp_rate2);
bf->bf_state.bfs_rc[2].rix = rix;
bf->bf_state.bfs_rc[2].tries = params->ibp_try2;
rix = ath_tx_findrix(sc, params->ibp_rate3);
bf->bf_state.bfs_rc[3].rix = rix;
bf->bf_state.bfs_rc[3].tries = params->ibp_try3;
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* All the required rate control decisions have been made;
* fill in the rc flags.
*/
ath_tx_rate_fill_rcflags(sc, bf);
/* NB: no buffered multicast in power save support */
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* If we're overiding the ADDBA destination, dump directly
* into the hardware queue, right after any pending
* frames to that node are.
*/
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: dooverride=%d\n",
__func__, do_override);
#if 1
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* Put addba frames in the right place in the right TID/HWQ.
*/
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (do_override) {
bf->bf_state.bfs_txflags |= HAL_TXDESC_CLRDMASK;
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* XXX if it's addba frames, should we be leaking
* them out via the frame leak method?
* XXX for now let's not risk it; but we may wish
* to investigate this later.
*/
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_xmit_normal(sc, sc->sc_ac2q[pri], bf);
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
} else if (ath_tx_should_swq_frame(sc, ATH_NODE(ni), m0,
&queue_to_head)) {
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Queue to software queue */
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
ath_tx_swq(sc, ni, sc->sc_ac2q[pri], queue_to_head, bf);
} else {
bf->bf_state.bfs_txflags |= HAL_TXDESC_CLRDMASK;
ath_tx_xmit_normal(sc, sc->sc_ac2q[pri], bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
#else
/* Direct-dispatch to the hardware */
bf->bf_state.bfs_txflags |= HAL_TXDESC_CLRDMASK;
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* Update the current leak count if
* we're leaking frames; and set the
* MORE flag as appropriate.
*/
ath_tx_leak_count_update(sc, tid, bf);
ath_tx_xmit_normal(sc, sc->sc_ac2q[pri], bf);
#endif
return 0;
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Send a raw frame.
*
* This can be called by net80211.
*/
int
ath_raw_xmit(struct ieee80211_node *ni, struct mbuf *m,
const struct ieee80211_bpf_params *params)
{
struct ieee80211com *ic = ni->ni_ic;
struct ifnet *ifp = ic->ic_ifp;
struct ath_softc *sc = ifp->if_softc;
struct ath_buf *bf;
struct ieee80211_frame *wh = mtod(m, struct ieee80211_frame *);
int error = 0;
Flesh out some slightly dirty reset/channel change serialisation code for the ath(4) driver. Currently, there's nothing stopping reset, channel change and general TX/RX from overlapping with each other. This wasn't a big deal with pre-11n traffic as it just results in some dropped frames. It's possible this may have also caused some inconsistencies and badly-setup hardware. Since locks can't be held across all of this (the Linux solution) due to LORs with the network stack locks, some state counter variables are used to track what parts of the code the driver is currently in. When the hardware is being reset, it disables the taskqueue and waits for pending interrupts, tx, rx and tx completion before it begins the reset or channel change. TX and RX both abort if called during an active reset or channel change. Finally, the reset path now doesn't flush frames if ATH_RESET_NOLOSS is set. Instead, completed TX and RX frames are passed back up to net80211 before the reset occurs. This is not without problems: * Raw frame xmit are just dropped, rather than placed on a queue. The net80211 stack should be the one which queues these frames rather than the driver. * It's all very messy. It'd be better if these hardware operations were serialised on some kind of work queue, rather than hoping they can be run in parallel. * The taskqueue block/unblock may occur in parallel with the newstate() function - which shuts down the taskqueue and restarts it once the new state is known. It's likely these operations should be refcounted so the taskqueue is restored once no other areas in the code wish to suspend operations. * .. interrupt disable/enable should likely be refcounted as well. With this work, the driver does not drop frames during stuck beacon or fatal errors and thus 11n traffic continues to run correctly. Default and full resets however do still drop frames and it's possible this may occur, causing traffic loss and session stalls. Sponsored by: Hobnob, Inc.
2011-11-18 05:06:30 +00:00
ATH_PCU_LOCK(sc);
if (sc->sc_inreset_cnt > 0) {
DPRINTF(sc, ATH_DEBUG_XMIT,
"%s: sc_inreset_cnt > 0; bailing\n", __func__);
Flesh out some slightly dirty reset/channel change serialisation code for the ath(4) driver. Currently, there's nothing stopping reset, channel change and general TX/RX from overlapping with each other. This wasn't a big deal with pre-11n traffic as it just results in some dropped frames. It's possible this may have also caused some inconsistencies and badly-setup hardware. Since locks can't be held across all of this (the Linux solution) due to LORs with the network stack locks, some state counter variables are used to track what parts of the code the driver is currently in. When the hardware is being reset, it disables the taskqueue and waits for pending interrupts, tx, rx and tx completion before it begins the reset or channel change. TX and RX both abort if called during an active reset or channel change. Finally, the reset path now doesn't flush frames if ATH_RESET_NOLOSS is set. Instead, completed TX and RX frames are passed back up to net80211 before the reset occurs. This is not without problems: * Raw frame xmit are just dropped, rather than placed on a queue. The net80211 stack should be the one which queues these frames rather than the driver. * It's all very messy. It'd be better if these hardware operations were serialised on some kind of work queue, rather than hoping they can be run in parallel. * The taskqueue block/unblock may occur in parallel with the newstate() function - which shuts down the taskqueue and restarts it once the new state is known. It's likely these operations should be refcounted so the taskqueue is restored once no other areas in the code wish to suspend operations. * .. interrupt disable/enable should likely be refcounted as well. With this work, the driver does not drop frames during stuck beacon or fatal errors and thus 11n traffic continues to run correctly. Default and full resets however do still drop frames and it's possible this may occur, causing traffic loss and session stalls. Sponsored by: Hobnob, Inc.
2011-11-18 05:06:30 +00:00
error = EIO;
ATH_PCU_UNLOCK(sc);
goto bad0;
}
sc->sc_txstart_cnt++;
ATH_PCU_UNLOCK(sc);
ATH_TX_LOCK(sc);
if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0 || sc->sc_invalid) {
DPRINTF(sc, ATH_DEBUG_XMIT, "%s: discard frame, %s", __func__,
(ifp->if_drv_flags & IFF_DRV_RUNNING) == 0 ?
"!running" : "invalid");
m_freem(m);
error = ENETDOWN;
goto bad;
}
/*
* Enforce how deep the multicast queue can grow.
*
* XXX duplicated in ath_tx_start().
*/
if (IEEE80211_IS_MULTICAST(wh->i_addr1)) {
Implement the replacement EDMA FIFO code. (Yes, the previous code temporarily broke EDMA TX. I'm sorry; I should've actually setup ATH_BUF_FIFOEND on frames so txq->axq_fifo_depth was cleared!) This code implements a whole bunch of sorely needed EDMA TX improvements along with CABQ TX support. The specifics: * When filling/refilling the FIFO, use the new TXQ staging queue for FIFO frames * Tag frames with ATH_BUF_FIFOPTR and ATH_BUF_FIFOEND correctly. For now the non-CABQ transmit path pushes one frame into the TXQ staging queue without setting up the intermediary link pointers to chain them together, so draining frames from the txq staging queue to the FIFO queue occurs AMPDU / MPDU at a time. * In the CABQ case, manually tag the list with ATH_BUF_FIFOPTR and ATH_BUF_FIFOEND so a chain of frames is pushed into the FIFO at once. * Now that frames are in a FIFO pending queue, we can top up the FIFO after completing a single frame. This means we can keep it filled rather than waiting for it drain and _then_ adding more frames. * The EDMA restart routine now walks the FIFO queue in the TXQ rather than the pending queue and re-initialises the FIFO with that. * When restarting EDMA, we may have partially completed sending a list. So stamp the first frame that we see in a list with ATH_BUF_FIFOPTR and push _that_ into the hardware. * When completing frames, only check those on the FIFO queue. We should never ever queue frames from the pending queue direct to the hardware, so there's no point in checking. * Until I figure out what's going on, make sure if the TXSTATUS for an empty queue pops up, complain loudly and continue. This will stop the panics that people are seeing. I'll add some code later which will assist in ensuring I'm populating each descriptor with the correct queue ID. * When considering whether to queue frames to the hardware queue directly or software queue frames, make sure the depth of the FIFO is taken into account now. * When completing frames, tag them with ATH_BUF_BUSY if they're not the final frame in a FIFO list. The same holding descriptor behaviour is required when handling descriptors linked together with a link pointer as the hardware will re-read the previous descriptor to refresh the link pointer before contiuning. * .. and if we complete the FIFO list (ie, the buffer has ATH_BUF_FIFOEND set), then we don't need the holding buffer any longer. Thus, free it. Tested: * AR9380/AR9580, STA and hostap * AR9280, STA/hostap TODO: * I don't yet trust that the EDMA restart routine is totally correct in all circumstances. I'll continue to thrash this out under heavy multiple-TXQ traffic load and fix whatever pops up.
2013-03-26 20:04:45 +00:00
if (sc->sc_cabq->axq_depth + sc->sc_cabq->fifo.axq_depth
> sc->sc_txq_mcastq_maxdepth) {
sc->sc_stats.ast_tx_mcastq_overflow++;
error = ENOBUFS;
}
if (error != 0) {
m_freem(m);
goto bad;
}
}
/*
* Grab a TX buffer and associated resources.
*/
bf = ath_getbuf(sc, ATH_BUFTYPE_MGMT);
if (bf == NULL) {
sc->sc_stats.ast_tx_nobuf++;
m_freem(m);
error = ENOBUFS;
goto bad;
}
ATH_KTR(sc, ATH_KTR_TX, 3, "ath_raw_xmit: m=%p, params=%p, bf=%p\n",
m, params, bf);
if (params == NULL) {
/*
* Legacy path; interpret frame contents to decide
* precisely how to send the frame.
*/
if (ath_tx_start(sc, ni, bf, m)) {
error = EIO; /* XXX */
goto bad2;
}
} else {
/*
* Caller supplied explicit parameters to use in
* sending the frame.
*/
if (ath_tx_raw_start(sc, ni, bf, m, params)) {
error = EIO; /* XXX */
goto bad2;
}
}
sc->sc_wd_timer = 5;
ifp->if_opackets++;
sc->sc_stats.ast_tx_raw++;
/*
* Update the TIM - if there's anything queued to the
* software queue and power save is enabled, we should
* set the TIM.
*/
ath_tx_update_tim(sc, ni, 1);
ATH_TX_UNLOCK(sc);
Flesh out some slightly dirty reset/channel change serialisation code for the ath(4) driver. Currently, there's nothing stopping reset, channel change and general TX/RX from overlapping with each other. This wasn't a big deal with pre-11n traffic as it just results in some dropped frames. It's possible this may have also caused some inconsistencies and badly-setup hardware. Since locks can't be held across all of this (the Linux solution) due to LORs with the network stack locks, some state counter variables are used to track what parts of the code the driver is currently in. When the hardware is being reset, it disables the taskqueue and waits for pending interrupts, tx, rx and tx completion before it begins the reset or channel change. TX and RX both abort if called during an active reset or channel change. Finally, the reset path now doesn't flush frames if ATH_RESET_NOLOSS is set. Instead, completed TX and RX frames are passed back up to net80211 before the reset occurs. This is not without problems: * Raw frame xmit are just dropped, rather than placed on a queue. The net80211 stack should be the one which queues these frames rather than the driver. * It's all very messy. It'd be better if these hardware operations were serialised on some kind of work queue, rather than hoping they can be run in parallel. * The taskqueue block/unblock may occur in parallel with the newstate() function - which shuts down the taskqueue and restarts it once the new state is known. It's likely these operations should be refcounted so the taskqueue is restored once no other areas in the code wish to suspend operations. * .. interrupt disable/enable should likely be refcounted as well. With this work, the driver does not drop frames during stuck beacon or fatal errors and thus 11n traffic continues to run correctly. Default and full resets however do still drop frames and it's possible this may occur, causing traffic loss and session stalls. Sponsored by: Hobnob, Inc.
2011-11-18 05:06:30 +00:00
ATH_PCU_LOCK(sc);
sc->sc_txstart_cnt--;
ATH_PCU_UNLOCK(sc);
return 0;
bad2:
ATH_KTR(sc, ATH_KTR_TX, 3, "ath_raw_xmit: bad2: m=%p, params=%p, "
"bf=%p",
m,
params,
bf);
ATH_TXBUF_LOCK(sc);
ath_returnbuf_head(sc, bf);
ATH_TXBUF_UNLOCK(sc);
bad:
ATH_TX_UNLOCK(sc);
Flesh out some slightly dirty reset/channel change serialisation code for the ath(4) driver. Currently, there's nothing stopping reset, channel change and general TX/RX from overlapping with each other. This wasn't a big deal with pre-11n traffic as it just results in some dropped frames. It's possible this may have also caused some inconsistencies and badly-setup hardware. Since locks can't be held across all of this (the Linux solution) due to LORs with the network stack locks, some state counter variables are used to track what parts of the code the driver is currently in. When the hardware is being reset, it disables the taskqueue and waits for pending interrupts, tx, rx and tx completion before it begins the reset or channel change. TX and RX both abort if called during an active reset or channel change. Finally, the reset path now doesn't flush frames if ATH_RESET_NOLOSS is set. Instead, completed TX and RX frames are passed back up to net80211 before the reset occurs. This is not without problems: * Raw frame xmit are just dropped, rather than placed on a queue. The net80211 stack should be the one which queues these frames rather than the driver. * It's all very messy. It'd be better if these hardware operations were serialised on some kind of work queue, rather than hoping they can be run in parallel. * The taskqueue block/unblock may occur in parallel with the newstate() function - which shuts down the taskqueue and restarts it once the new state is known. It's likely these operations should be refcounted so the taskqueue is restored once no other areas in the code wish to suspend operations. * .. interrupt disable/enable should likely be refcounted as well. With this work, the driver does not drop frames during stuck beacon or fatal errors and thus 11n traffic continues to run correctly. Default and full resets however do still drop frames and it's possible this may occur, causing traffic loss and session stalls. Sponsored by: Hobnob, Inc.
2011-11-18 05:06:30 +00:00
ATH_PCU_LOCK(sc);
sc->sc_txstart_cnt--;
ATH_PCU_UNLOCK(sc);
bad0:
ATH_KTR(sc, ATH_KTR_TX, 2, "ath_raw_xmit: bad0: m=%p, params=%p",
m, params);
ifp->if_oerrors++;
sc->sc_stats.ast_tx_raw_fail++;
ieee80211_free_node(ni);
Flesh out some slightly dirty reset/channel change serialisation code for the ath(4) driver. Currently, there's nothing stopping reset, channel change and general TX/RX from overlapping with each other. This wasn't a big deal with pre-11n traffic as it just results in some dropped frames. It's possible this may have also caused some inconsistencies and badly-setup hardware. Since locks can't be held across all of this (the Linux solution) due to LORs with the network stack locks, some state counter variables are used to track what parts of the code the driver is currently in. When the hardware is being reset, it disables the taskqueue and waits for pending interrupts, tx, rx and tx completion before it begins the reset or channel change. TX and RX both abort if called during an active reset or channel change. Finally, the reset path now doesn't flush frames if ATH_RESET_NOLOSS is set. Instead, completed TX and RX frames are passed back up to net80211 before the reset occurs. This is not without problems: * Raw frame xmit are just dropped, rather than placed on a queue. The net80211 stack should be the one which queues these frames rather than the driver. * It's all very messy. It'd be better if these hardware operations were serialised on some kind of work queue, rather than hoping they can be run in parallel. * The taskqueue block/unblock may occur in parallel with the newstate() function - which shuts down the taskqueue and restarts it once the new state is known. It's likely these operations should be refcounted so the taskqueue is restored once no other areas in the code wish to suspend operations. * .. interrupt disable/enable should likely be refcounted as well. With this work, the driver does not drop frames during stuck beacon or fatal errors and thus 11n traffic continues to run correctly. Default and full resets however do still drop frames and it's possible this may occur, causing traffic loss and session stalls. Sponsored by: Hobnob, Inc.
2011-11-18 05:06:30 +00:00
return error;
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Some helper functions */
/*
* ADDBA (and potentially others) need to be placed in the same
* hardware queue as the TID/node it's relating to. This is so
* it goes out after any pending non-aggregate frames to the
* same node/TID.
*
* If this isn't done, the ADDBA can go out before the frames
* queued in hardware. Even though these frames have a sequence
* number -earlier- than the ADDBA can be transmitted (but
* no frames whose sequence numbers are after the ADDBA should
* be!) they'll arrive after the ADDBA - and the receiving end
* will simply drop them as being out of the BAW.
*
* The frames can't be appended to the TID software queue - it'll
* never be sent out. So these frames have to be directly
* dispatched to the hardware, rather than queued in software.
* So if this function returns true, the TXQ has to be
* overridden and it has to be directly dispatched.
*
* It's a dirty hack, but someone's gotta do it.
*/
/*
* XXX doesn't belong here!
*/
static int
ieee80211_is_action(struct ieee80211_frame *wh)
{
/* Type: Management frame? */
if ((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) !=
IEEE80211_FC0_TYPE_MGT)
return 0;
/* Subtype: Action frame? */
if ((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) !=
IEEE80211_FC0_SUBTYPE_ACTION)
return 0;
return 1;
}
#define MS(_v, _f) (((_v) & _f) >> _f##_S)
/*
* Return an alternate TID for ADDBA request frames.
*
* Yes, this likely should be done in the net80211 layer.
*/
static int
ath_tx_action_frame_override_queue(struct ath_softc *sc,
struct ieee80211_node *ni,
struct mbuf *m0, int *tid)
{
struct ieee80211_frame *wh = mtod(m0, struct ieee80211_frame *);
struct ieee80211_action_ba_addbarequest *ia;
uint8_t *frm;
uint16_t baparamset;
/* Not action frame? Bail */
if (! ieee80211_is_action(wh))
return 0;
/* XXX Not needed for frames we send? */
#if 0
/* Correct length? */
if (! ieee80211_parse_action(ni, m))
return 0;
#endif
/* Extract out action frame */
frm = (u_int8_t *)&wh[1];
ia = (struct ieee80211_action_ba_addbarequest *) frm;
/* Not ADDBA? Bail */
if (ia->rq_header.ia_category != IEEE80211_ACTION_CAT_BA)
return 0;
if (ia->rq_header.ia_action != IEEE80211_ACTION_BA_ADDBA_REQUEST)
return 0;
/* Extract TID, return it */
baparamset = le16toh(ia->rq_baparamset);
*tid = (int) MS(baparamset, IEEE80211_BAPS_TID);
return 1;
}
#undef MS
/* Per-node software queue operations */
/*
* Add the current packet to the given BAW.
* It is assumed that the current packet
*
* + fits inside the BAW;
* + already has had a sequence number allocated.
*
* Since the BAW status may be modified by both the ath task and
* the net80211/ifnet contexts, the TID must be locked.
*/
void
ath_tx_addto_baw(struct ath_softc *sc, struct ath_node *an,
struct ath_tid *tid, struct ath_buf *bf)
{
int index, cindex;
struct ieee80211_tx_ampdu *tap;
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (bf->bf_state.bfs_isretried)
return;
tap = ath_tx_get_tx_tid(an, tid->tid);
if (! bf->bf_state.bfs_dobaw) {
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
"%s: dobaw=0, seqno=%d, window %d:%d\n",
__func__, SEQNO(bf->bf_state.bfs_seqno),
tap->txa_start, tap->txa_wnd);
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (bf->bf_state.bfs_addedbaw)
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
"%s: re-added? tid=%d, seqno %d; window %d:%d; "
"baw head=%d tail=%d\n",
__func__, tid->tid, SEQNO(bf->bf_state.bfs_seqno),
tap->txa_start, tap->txa_wnd, tid->baw_head,
tid->baw_tail);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Verify that the given sequence number is not outside of the
* BAW. Complain loudly if that's the case.
*/
if (! BAW_WITHIN(tap->txa_start, tap->txa_wnd,
SEQNO(bf->bf_state.bfs_seqno))) {
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
"%s: bf=%p: outside of BAW?? tid=%d, seqno %d; window %d:%d; "
"baw head=%d tail=%d\n",
__func__, bf, tid->tid, SEQNO(bf->bf_state.bfs_seqno),
tap->txa_start, tap->txa_wnd, tid->baw_head,
tid->baw_tail);
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* ni->ni_txseqs[] is the currently allocated seqno.
* the txa state contains the current baw start.
*/
index = ATH_BA_INDEX(tap->txa_start, SEQNO(bf->bf_state.bfs_seqno));
cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
"%s: tid=%d, seqno %d; window %d:%d; index=%d cindex=%d "
"baw head=%d tail=%d\n",
__func__, tid->tid, SEQNO(bf->bf_state.bfs_seqno),
tap->txa_start, tap->txa_wnd, index, cindex, tid->baw_head,
tid->baw_tail);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
#if 0
assert(tid->tx_buf[cindex] == NULL);
#endif
if (tid->tx_buf[cindex] != NULL) {
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
"%s: ba packet dup (index=%d, cindex=%d, "
"head=%d, tail=%d)\n",
__func__, index, cindex, tid->baw_head, tid->baw_tail);
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
"%s: BA bf: %p; seqno=%d ; new bf: %p; seqno=%d\n",
__func__,
tid->tx_buf[cindex],
SEQNO(tid->tx_buf[cindex]->bf_state.bfs_seqno),
bf,
SEQNO(bf->bf_state.bfs_seqno)
);
}
tid->tx_buf[cindex] = bf;
if (index >= ((tid->baw_tail - tid->baw_head) &
(ATH_TID_MAX_BUFS - 1))) {
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
tid->baw_tail = cindex;
INCR(tid->baw_tail, ATH_TID_MAX_BUFS);
}
}
/*
* Flip the BAW buffer entry over from the existing one to the new one.
*
* When software retransmitting a (sub-)frame, it is entirely possible that
* the frame ath_buf is marked as BUSY and can't be immediately reused.
* In that instance the buffer is cloned and the new buffer is used for
* retransmit. We thus need to update the ath_buf slot in the BAW buf
* tracking array to maintain consistency.
*/
static void
ath_tx_switch_baw_buf(struct ath_softc *sc, struct ath_node *an,
struct ath_tid *tid, struct ath_buf *old_bf, struct ath_buf *new_bf)
{
int index, cindex;
struct ieee80211_tx_ampdu *tap;
int seqno = SEQNO(old_bf->bf_state.bfs_seqno);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
tap = ath_tx_get_tx_tid(an, tid->tid);
index = ATH_BA_INDEX(tap->txa_start, seqno);
cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
/*
* Just warn for now; if it happens then we should find out
* about it. It's highly likely the aggregation session will
* soon hang.
*/
if (old_bf->bf_state.bfs_seqno != new_bf->bf_state.bfs_seqno) {
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
"%s: retransmitted buffer"
" has mismatching seqno's, BA session may hang.\n",
__func__);
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
"%s: old seqno=%d, new_seqno=%d\n", __func__,
old_bf->bf_state.bfs_seqno, new_bf->bf_state.bfs_seqno);
}
if (tid->tx_buf[cindex] != old_bf) {
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
"%s: ath_buf pointer incorrect; "
" has m BA session may hang.\n", __func__);
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
"%s: old bf=%p, new bf=%p\n", __func__, old_bf, new_bf);
}
tid->tx_buf[cindex] = new_bf;
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* seq_start - left edge of BAW
* seq_next - current/next sequence number to allocate
*
* Since the BAW status may be modified by both the ath task and
* the net80211/ifnet contexts, the TID must be locked.
*/
static void
ath_tx_update_baw(struct ath_softc *sc, struct ath_node *an,
struct ath_tid *tid, const struct ath_buf *bf)
{
int index, cindex;
struct ieee80211_tx_ampdu *tap;
int seqno = SEQNO(bf->bf_state.bfs_seqno);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
tap = ath_tx_get_tx_tid(an, tid->tid);
index = ATH_BA_INDEX(tap->txa_start, seqno);
cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
"%s: tid=%d, baw=%d:%d, seqno=%d, index=%d, cindex=%d, "
"baw head=%d, tail=%d\n",
__func__, tid->tid, tap->txa_start, tap->txa_wnd, seqno, index,
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
cindex, tid->baw_head, tid->baw_tail);
/*
* If this occurs then we have a big problem - something else
* has slid tap->txa_start along without updating the BAW
* tracking start/end pointers. Thus the TX BAW state is now
* completely busted.
*
* But for now, since I haven't yet fixed TDMA and buffer cloning,
* it's quite possible that a cloned buffer is making its way
* here and causing it to fire off. Disable TDMA for now.
*/
if (tid->tx_buf[cindex] != bf) {
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
"%s: comp bf=%p, seq=%d; slot bf=%p, seqno=%d\n",
__func__, bf, SEQNO(bf->bf_state.bfs_seqno),
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
tid->tx_buf[cindex],
(tid->tx_buf[cindex] != NULL) ?
SEQNO(tid->tx_buf[cindex]->bf_state.bfs_seqno) : -1);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
tid->tx_buf[cindex] = NULL;
while (tid->baw_head != tid->baw_tail &&
!tid->tx_buf[tid->baw_head]) {
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
INCR(tap->txa_start, IEEE80211_SEQ_RANGE);
INCR(tid->baw_head, ATH_TID_MAX_BUFS);
}
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
"%s: baw is now %d:%d, baw head=%d\n",
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
__func__, tap->txa_start, tap->txa_wnd, tid->baw_head);
}
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
static void
ath_tx_leak_count_update(struct ath_softc *sc, struct ath_tid *tid,
struct ath_buf *bf)
{
struct ieee80211_frame *wh;
ATH_TX_LOCK_ASSERT(sc);
if (tid->an->an_leak_count > 0) {
wh = mtod(bf->bf_m, struct ieee80211_frame *);
/*
* Update MORE based on the software/net80211 queue states.
*/
if ((tid->an->an_stack_psq > 0)
|| (tid->an->an_swq_depth > 0))
wh->i_fc[1] |= IEEE80211_FC1_MORE_DATA;
else
wh->i_fc[1] &= ~IEEE80211_FC1_MORE_DATA;
DPRINTF(sc, ATH_DEBUG_NODE_PWRSAVE,
"%s: %6D: leak count = %d, psq=%d, swq=%d, MORE=%d\n",
__func__,
tid->an->an_node.ni_macaddr,
":",
tid->an->an_leak_count,
tid->an->an_stack_psq,
tid->an->an_swq_depth,
!! (wh->i_fc[1] & IEEE80211_FC1_MORE_DATA));
/*
* Re-sync the underlying buffer.
*/
bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap,
BUS_DMASYNC_PREWRITE);
tid->an->an_leak_count --;
}
}
static int
ath_tx_tid_can_tx_or_sched(struct ath_softc *sc, struct ath_tid *tid)
{
ATH_TX_LOCK_ASSERT(sc);
if (tid->an->an_leak_count > 0) {
return (1);
}
if (tid->paused)
return (0);
return (1);
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Mark the current node/TID as ready to TX.
*
* This is done to make it easy for the software scheduler to
* find which nodes have data to send.
*
* The TXQ lock must be held.
*/
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
void
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_tid_sched(struct ath_softc *sc, struct ath_tid *tid)
{
struct ath_txq *txq = sc->sc_ac2q[tid->ac];
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* If we are leaking out a frame to this destination
* for PS-POLL, ensure that we allow scheduling to
* occur.
*/
if (! ath_tx_tid_can_tx_or_sched(sc, tid))
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
return; /* paused, can't schedule yet */
if (tid->sched)
return; /* already scheduled */
tid->sched = 1;
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
#if 0
/*
* If this is a sleeping node we're leaking to, given
* it a higher priority. This is so bad for QoS it hurts.
*/
if (tid->an->an_leak_count) {
TAILQ_INSERT_HEAD(&txq->axq_tidq, tid, axq_qelem);
} else {
TAILQ_INSERT_TAIL(&txq->axq_tidq, tid, axq_qelem);
}
#endif
/*
* We can't do the above - it'll confuse the TXQ software
* scheduler which will keep checking the _head_ TID
* in the list to see if it has traffic. If we queue
* a TID to the head of the list and it doesn't transmit,
* we'll check it again.
*
* So, get the rest of this leaking frames support working
* and reliable first and _then_ optimise it so they're
* pushed out in front of any other pending software
* queued nodes.
*/
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
TAILQ_INSERT_TAIL(&txq->axq_tidq, tid, axq_qelem);
}
/*
* Mark the current node as no longer needing to be polled for
* TX packets.
*
* The TXQ lock must be held.
*/
static void
ath_tx_tid_unsched(struct ath_softc *sc, struct ath_tid *tid)
{
struct ath_txq *txq = sc->sc_ac2q[tid->ac];
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (tid->sched == 0)
return;
tid->sched = 0;
TAILQ_REMOVE(&txq->axq_tidq, tid, axq_qelem);
}
/*
* Assign a sequence number manually to the given frame.
*
* This should only be called for A-MPDU TX frames.
*/
static ieee80211_seq
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_tid_seqno_assign(struct ath_softc *sc, struct ieee80211_node *ni,
struct ath_buf *bf, struct mbuf *m0)
{
struct ieee80211_frame *wh;
int tid, pri;
ieee80211_seq seqno;
uint8_t subtype;
/* TID lookup */
wh = mtod(m0, struct ieee80211_frame *);
pri = M_WME_GETAC(m0); /* honor classification */
tid = WME_AC_TO_TID(pri);
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: pri=%d, tid=%d, qos has seq=%d\n",
__func__, pri, tid, IEEE80211_QOS_HAS_SEQ(wh));
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* XXX Is it a control frame? Ignore */
/* Does the packet require a sequence number? */
if (! IEEE80211_QOS_HAS_SEQ(wh))
return -1;
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Is it a QOS NULL Data frame? Give it a sequence number from
* the default TID (IEEE80211_NONQOS_TID.)
*
* The RX path of everything I've looked at doesn't include the NULL
* data frame sequence number in the aggregation state updates, so
* assigning it a sequence number there will cause a BAW hole on the
* RX side.
*/
subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
if (subtype == IEEE80211_FC0_SUBTYPE_QOS_NULL) {
/* XXX no locking for this TID? This is a bit of a problem. */
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
seqno = ni->ni_txseqs[IEEE80211_NONQOS_TID];
INCR(ni->ni_txseqs[IEEE80211_NONQOS_TID], IEEE80211_SEQ_RANGE);
} else {
/* Manually assign sequence number */
seqno = ni->ni_txseqs[tid];
INCR(ni->ni_txseqs[tid], IEEE80211_SEQ_RANGE);
}
*(uint16_t *)&wh->i_seq[0] = htole16(seqno << IEEE80211_SEQ_SEQ_SHIFT);
M_SEQNO_SET(m0, seqno);
/* Return so caller can do something with it if needed */
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: -> seqno=%d\n", __func__, seqno);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
return seqno;
}
/*
* Attempt to direct dispatch an aggregate frame to hardware.
* If the frame is out of BAW, queue.
* Otherwise, schedule it as a single frame.
*/
static void
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
ath_tx_xmit_aggr(struct ath_softc *sc, struct ath_node *an,
struct ath_txq *txq, struct ath_buf *bf)
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
{
struct ath_tid *tid = &an->an_tid[bf->bf_state.bfs_tid];
struct ieee80211_tx_ampdu *tap;
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
tap = ath_tx_get_tx_tid(an, tid->tid);
/* paused? queue */
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
if (! ath_tx_tid_can_tx_or_sched(sc, tid)) {
ATH_TID_INSERT_HEAD(tid, bf, bf_list);
/* XXX don't sched - we're paused! */
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
return;
}
/* outside baw? queue */
if (bf->bf_state.bfs_dobaw &&
(! BAW_WITHIN(tap->txa_start, tap->txa_wnd,
SEQNO(bf->bf_state.bfs_seqno)))) {
ATH_TID_INSERT_HEAD(tid, bf, bf_list);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_tid_sched(sc, tid);
return;
}
/*
* This is a temporary check and should be removed once
* all the relevant code paths have been fixed.
*
* During aggregate retries, it's possible that the head
* frame will fail (which has the bfs_aggr and bfs_nframes
* fields set for said aggregate) and will be retried as
* a single frame. In this instance, the values should
* be reset or the completion code will get upset with you.
*/
if (bf->bf_state.bfs_aggr != 0 || bf->bf_state.bfs_nframes > 1) {
2013-10-17 05:51:54 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
"%s: bfs_aggr=%d, bfs_nframes=%d\n", __func__,
bf->bf_state.bfs_aggr, bf->bf_state.bfs_nframes);
bf->bf_state.bfs_aggr = 0;
bf->bf_state.bfs_nframes = 1;
}
/* Update CLRDMASK just before this frame is queued */
ath_tx_update_clrdmask(sc, tid, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Direct dispatch to hardware */
ath_tx_do_ratelookup(sc, bf);
ath_tx_calc_duration(sc, bf);
ath_tx_calc_protection(sc, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_set_rtscts(sc, bf);
ath_tx_rate_fill_rcflags(sc, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_setds(sc, bf);
/* Statistics */
sc->sc_aggr_stats.aggr_low_hwq_single_pkt++;
/* Track per-TID hardware queue depth correctly */
tid->hwq_depth++;
/* Add to BAW */
if (bf->bf_state.bfs_dobaw) {
ath_tx_addto_baw(sc, an, tid, bf);
bf->bf_state.bfs_addedbaw = 1;
}
/* Set completion handler, multi-frame aggregate or not */
bf->bf_comp = ath_tx_aggr_comp;
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* Update the current leak count if
* we're leaking frames; and set the
* MORE flag as appropriate.
*/
ath_tx_leak_count_update(sc, tid, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Hand off to hardware */
ath_tx_handoff(sc, txq, bf);
}
/*
* Attempt to send the packet.
* If the queue isn't busy, direct-dispatch.
* If the queue is busy enough, queue the given packet on the
* relevant software queue.
*/
void
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
ath_tx_swq(struct ath_softc *sc, struct ieee80211_node *ni,
struct ath_txq *txq, int queue_to_head, struct ath_buf *bf)
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
{
struct ath_node *an = ATH_NODE(ni);
struct ieee80211_frame *wh;
struct ath_tid *atid;
int pri, tid;
struct mbuf *m0 = bf->bf_m;
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Fetch the TID - non-QoS frames get assigned to TID 16 */
wh = mtod(m0, struct ieee80211_frame *);
pri = ath_tx_getac(sc, m0);
tid = ath_tx_gettid(sc, m0);
atid = &an->an_tid[tid];
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: bf=%p, pri=%d, tid=%d, qos=%d\n",
__func__, bf, pri, tid, IEEE80211_QOS_HAS_SEQ(wh));
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Set local packet state, used to queue packets to hardware */
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
/* XXX potentially duplicate info, re-check */
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
bf->bf_state.bfs_tid = tid;
bf->bf_state.bfs_tx_queue = txq->axq_qnum;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
bf->bf_state.bfs_pri = pri;
/*
* If the hardware queue isn't busy, queue it directly.
* If the hardware queue is busy, queue it.
* If the TID is paused or the traffic it outside BAW, software
* queue it.
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
*
* If the node is in power-save and we're leaking a frame,
* leak a single frame.
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
*/
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
if (! ath_tx_tid_can_tx_or_sched(sc, atid)) {
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* TID is paused, queue */
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: paused\n", __func__);
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* If the caller requested that it be sent at a high
* priority, queue it at the head of the list.
*/
if (queue_to_head)
ATH_TID_INSERT_HEAD(atid, bf, bf_list);
else
ATH_TID_INSERT_TAIL(atid, bf, bf_list);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
} else if (ath_tx_ampdu_pending(sc, an, tid)) {
/* AMPDU pending; queue */
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: pending\n", __func__);
ATH_TID_INSERT_TAIL(atid, bf, bf_list);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* XXX sched? */
} else if (ath_tx_ampdu_running(sc, an, tid)) {
/* AMPDU running, attempt direct dispatch if possible */
/*
* Always queue the frame to the tail of the list.
*/
ATH_TID_INSERT_TAIL(atid, bf, bf_list);
/*
* If the hardware queue isn't busy, direct dispatch
* the head frame in the list. Don't schedule the
* TID - let it build some more frames first?
*
* When running A-MPDU, always just check the hardware
* queue depth against the aggregate frame limit.
* We don't want to burst a large number of single frames
* out to the hardware; we want to aggressively hold back.
*
* Otherwise, schedule the TID.
*/
/* XXX TXQ locking */
if (txq->axq_depth + txq->fifo.axq_depth < sc->sc_hwq_limit_aggr) {
bf = ATH_TID_FIRST(atid);
ATH_TID_REMOVE(atid, bf, bf_list);
/*
* Ensure it's definitely treated as a non-AMPDU
* frame - this information may have been left
* over from a previous attempt.
*/
bf->bf_state.bfs_aggr = 0;
bf->bf_state.bfs_nframes = 1;
/* Queue to the hardware */
Migrate the ath_hal_filltxdesc() API to take a list of buffer/seglen values. The existing API only exposes 'seglen' (the current buffer (segment) length) with the data buffer pointer set in 'ds_data'. This is fine for the legacy DMA engine but it won't work for the EDMA engines. The EDMA engine has a significantly different TX descriptor layout. * The legacy DMA engine had a ds_data pointer at the same offset in the descriptor for both TX and RX buffers; * The EDMA engine has no ds_data for RX - the data is DMAed after the descriptor; * The EDMA engine has support for 4 TX buffer/segment pairs in the TX DMA descriptor; * The EDMA TX completion is in a different FIFO, and the driver will 'link' the status completion entry to a QCU by a "QCU ID". I don't know why it's just not filled in by the hardware, alas. So given that, here are the changes: * Instead of directly fondling 'ds_data' in ath_desc, change the ath_hal_filltxdesc() to take an array of buffer pointers as well as segment len pointers; * The EDMA TX completion status wants a descriptor and queue id. This (for now) uses bf_state.bfs_txq and will extract the hardware QCU ID from that. * .. and this is ugly and wasteful; it should change to just store the QCU in the bf_state and save 3/7 bytes in the process. Now, the weird crap: * The aggregate TX path was using bf_state->bfs_txq for the TXQ, rather than taking a function argument. I've tidied that up. * The multicast queue frames get put on a software TXQ and then that is appended to the hardware CABQ when appropriate. So for now, make sure that bf_state->bfs_txq points at the CABQ when adding frames to the multicast queue. * .. but the multicast queue TX path for now doesn't use the software queue and instead (a) directly sets up the descriptor contents at that point; (b) the frames on the vap->avp_mcastq are then just appended wholesale to the CABQ. So for now, I don't have to worry about making the multicast path work with aggregation or the per-TID software queue. Phew. What's left to do: * I need to modify the 11n ath_hal_chaintxdesc() API to do the same. I'll do that in a subsequent commit. * Remove bf_state.bfs_txq entirely and store the QCU as appropriate. * .. then do the runtime "is this going on the right HWQ?" checks using that, rather than comparing pointer values. Tested on: * AR9280 STA/AP * AR5416 STA/AP
2012-08-05 10:12:27 +00:00
ath_tx_xmit_aggr(sc, an, txq, bf);
DPRINTF(sc, ATH_DEBUG_SW_TX,
"%s: xmit_aggr\n",
__func__);
} else {
DPRINTF(sc, ATH_DEBUG_SW_TX,
"%s: ampdu; swq'ing\n",
__func__);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_tid_sched(sc, atid);
}
/*
* If we're not doing A-MPDU, be prepared to direct dispatch
* up to both limits if possible. This particular corner
* case may end up with packet starvation between aggregate
* traffic and non-aggregate traffic: we wnat to ensure
* that non-aggregate stations get a few frames queued to the
* hardware before the aggregate station(s) get their chance.
*
* So if you only ever see a couple of frames direct dispatched
* to the hardware from a non-AMPDU client, check both here
* and in the software queue dispatcher to ensure that those
* non-AMPDU stations get a fair chance to transmit.
*/
/* XXX TXQ locking */
} else if ((txq->axq_depth + txq->fifo.axq_depth < sc->sc_hwq_limit_nonaggr) &&
(txq->axq_aggr_depth < sc->sc_hwq_limit_aggr)) {
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* AMPDU not running, attempt direct dispatch */
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: xmit_normal\n", __func__);
/* See if clrdmask needs to be set */
ath_tx_update_clrdmask(sc, atid, bf);
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* Update the current leak count if
* we're leaking frames; and set the
* MORE flag as appropriate.
*/
ath_tx_leak_count_update(sc, atid, bf);
/*
* Dispatch the frame.
*/
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_xmit_normal(sc, txq, bf);
} else {
/* Busy; queue */
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: swq'ing\n", __func__);
ATH_TID_INSERT_TAIL(atid, bf, bf_list);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_tid_sched(sc, atid);
}
}
/*
* Only set the clrdmask bit if none of the nodes are currently
* filtered.
*
* XXX TODO: go through all the callers and check to see
* which are being called in the context of looping over all
* TIDs (eg, if all tids are being paused, resumed, etc.)
* That'll avoid O(n^2) complexity here.
*/
static void
ath_tx_set_clrdmask(struct ath_softc *sc, struct ath_node *an)
{
int i;
ATH_TX_LOCK_ASSERT(sc);
for (i = 0; i < IEEE80211_TID_SIZE; i++) {
if (an->an_tid[i].isfiltered == 1)
return;
}
an->clrdmask = 1;
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Configure the per-TID node state.
*
* This likely belongs in if_ath_node.c but I can't think of anywhere
* else to put it just yet.
*
* This sets up the SLISTs and the mutex as appropriate.
*/
void
ath_tx_tid_init(struct ath_softc *sc, struct ath_node *an)
{
int i, j;
struct ath_tid *atid;
for (i = 0; i < IEEE80211_TID_SIZE; i++) {
atid = &an->an_tid[i];
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/* XXX now with this bzer(), is the field 0'ing needed? */
bzero(atid, sizeof(*atid));
TAILQ_INIT(&atid->tid_q);
TAILQ_INIT(&atid->filtq.tid_q);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
atid->tid = i;
atid->an = an;
for (j = 0; j < ATH_TID_MAX_BUFS; j++)
atid->tx_buf[j] = NULL;
atid->baw_head = atid->baw_tail = 0;
atid->paused = 0;
atid->sched = 0;
atid->hwq_depth = 0;
atid->cleanup_inprogress = 0;
if (i == IEEE80211_NONQOS_TID)
Map the non-QoS TID to the voice queue, in order to ensure important things like EAPOL frames make it out. After a whole bunch of hacking/testing, I discovered that they weren't being early-dropped by the stack (but I should look at ensuring that later..) but were even making to the hardware transmit queue. They were mostly even being received by the remote end. However, the remote end was completely ignoring them. This didn't happen under 150-170MBit TCP tests as I'm guessing the TX queue stayed very busy and the STA didn't do any scanning. However, when doing 100Mbit/s of TCP traffic, the STA would do background scanning - which involves it coming in and out of powersave mode with the AP. Now, this is a total and utter hack around the real problems, which are: * I need to implement proper power save handling and integrate it into the filtered frames support, so the driver/stack doesn't send frames whilst the station is actually in sleep; * .. but frames were actually making it to the STA (macbook pro) and the AP did receive an ACK; but a tcpdump on the receiving side showed the EAPOL frame never made it. So the stack was dropping it for some reason; * Importantly - the EAPOL frames are currently going into the non-QoS TID, which maps to the BE queue and is susceptible to that queue being busy doing other things, but; * There's other traffic going on in the non-QoS TID from other contexts when scanning is going on and it's possible there's some races causing sequence number/IV issues, but; * Importantly importantlly, I think the interaction with TID 16 multicast traffic in power save mode is causing issues - since I -believe- the sequence number space being used by the EAPOL frames on TID 16 overlaps with the multicast frames that have sequence numbers allocated and are then stuffed on the cabq. Since with EAPOL frames being in TID 16 and queued to the BE queue, it's going to be waiting to be serviced with all of the aggregate traffic going on - and if the CABQ gets emptied beforehand, those TID 16 multicast frames with sequence numbers will go out beforehand. Now, there's quite likely a bunch of "stuff happening slightly out of sequence" going on due to the nature of the TX path (read: lots of overlapping and concurrent ath_start() and ath_raw_xmit() calls going on, sigh) but I thought I had caught them all and stuffed each TID TX behind a lock (that lasted as long as it needed to in order to get the frame onto the relevant destination queue - thus keeping things in order.) Unfortunately the last problem is the big one and I'm going to stare at it some more. If it _is_ So this is a work around for now to ensure that EAPOL frames actually make it out before any other stuff in the non-QoS TID and HOPEFULLY before the CABQ gets active. I'm now going to spend a little time in the TX path figuring out exactly why the sender is rejecting things. There's two (well, three if you count EAPOL contents invalid) possibilities: * The sequence number is out of order (ie, something else like the multicast traffic on CABQ) is going out first on TID 16; * The CCMP IV is out of order (similar to above - but less likely, as the TX key for multicast traffic is different to unicast traffic); * EAPOL contents strangely invalid. AP: Ubiquiti RSPRO, AR9160/AR9220 NICs STA: Macbook Pro, Broadcom 11n NIC
2012-09-26 03:45:42 +00:00
atid->ac = ATH_NONQOS_TID_AC;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
else
atid->ac = TID_TO_WME_AC(i);
}
an->clrdmask = 1; /* Always start by setting this bit */
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
/*
* Pause the current TID. This stops packets from being transmitted
* on it.
*
* Since this is also called from upper layers as well as the driver,
* it will get the TID lock.
*/
static void
ath_tx_tid_pause(struct ath_softc *sc, struct ath_tid *tid)
{
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
tid->paused++;
DPRINTF(sc, ATH_DEBUG_SW_TX_CTRL, "%s: paused = %d\n",
__func__, tid->paused);
}
/*
* Unpause the current TID, and schedule it if needed.
*/
static void
ath_tx_tid_resume(struct ath_softc *sc, struct ath_tid *tid)
{
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* There's some odd places where ath_tx_tid_resume() is called
* when it shouldn't be; this works around that particular issue
* until it's actually resolved.
*/
if (tid->paused == 0) {
DPRINTF(sc, ATH_DEBUG_SW_TX_CTRL,
"%s: %6D: paused=0?\n", __func__,
tid->an->an_node.ni_macaddr, ":");
} else {
tid->paused--;
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX_CTRL, "%s: unpaused = %d\n",
__func__, tid->paused);
if (tid->paused)
return;
/*
* Override the clrdmask configuration for the next frame
* from this TID, just to get the ball rolling.
*/
ath_tx_set_clrdmask(sc, tid->an);
if (tid->axq_depth == 0)
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
return;
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/* XXX isfiltered shouldn't ever be 0 at this point */
if (tid->isfiltered == 1) {
DPRINTF(sc, ATH_DEBUG_SW_TX_CTRL, "%s: filtered?!\n",
__func__);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
return;
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_tid_sched(sc, tid);
/*
* Queue the software TX scheduler.
*/
ath_tx_swq_kick(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/*
* Add the given ath_buf to the TID filtered frame list.
* This requires the TID be filtered.
*/
static void
ath_tx_tid_filt_addbuf(struct ath_softc *sc, struct ath_tid *tid,
struct ath_buf *bf)
{
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
if (!tid->isfiltered)
DPRINTF(sc, ATH_DEBUG_SW_TX_FILT, "%s: not filtered?!\n",
__func__);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX_FILT, "%s: bf=%p\n", __func__, bf);
/* Set the retry bit and bump the retry counter */
ath_tx_set_retry(sc, bf);
sc->sc_stats.ast_tx_swfiltered++;
ATH_TID_FILT_INSERT_TAIL(tid, bf, bf_list);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
}
/*
* Handle a completed filtered frame from the given TID.
* This just enables/pauses the filtered frame state if required
* and appends the filtered frame to the filtered queue.
*/
static void
ath_tx_tid_filt_comp_buf(struct ath_softc *sc, struct ath_tid *tid,
struct ath_buf *bf)
{
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
if (! tid->isfiltered) {
DPRINTF(sc, ATH_DEBUG_SW_TX_FILT, "%s: filter transition\n",
__func__);
tid->isfiltered = 1;
ath_tx_tid_pause(sc, tid);
}
/* Add the frame to the filter queue */
ath_tx_tid_filt_addbuf(sc, tid, bf);
}
/*
* Complete the filtered frame TX completion.
*
* If there are no more frames in the hardware queue, unpause/unfilter
* the TID if applicable. Otherwise we will wait for a node PS transition
* to unfilter.
*/
static void
ath_tx_tid_filt_comp_complete(struct ath_softc *sc, struct ath_tid *tid)
{
struct ath_buf *bf;
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
if (tid->hwq_depth != 0)
return;
DPRINTF(sc, ATH_DEBUG_SW_TX_FILT, "%s: hwq=0, transition back\n",
__func__);
tid->isfiltered = 0;
/* XXX ath_tx_tid_resume() also calls ath_tx_set_clrdmask()! */
ath_tx_set_clrdmask(sc, tid->an);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/* XXX this is really quite inefficient */
while ((bf = ATH_TID_FILT_LAST(tid, ath_bufhead_s)) != NULL) {
ATH_TID_FILT_REMOVE(tid, bf, bf_list);
ATH_TID_INSERT_HEAD(tid, bf, bf_list);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
}
ath_tx_tid_resume(sc, tid);
}
/*
* Called when a single (aggregate or otherwise) frame is completed.
*
* Returns 1 if the buffer could be added to the filtered list
* (cloned or otherwise), 0 if the buffer couldn't be added to the
* filtered list (failed clone; expired retry) and the caller should
* free it and handle it like a failure (eg by sending a BAR.)
*/
static int
ath_tx_tid_filt_comp_single(struct ath_softc *sc, struct ath_tid *tid,
struct ath_buf *bf)
{
struct ath_buf *nbf;
int retval;
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/*
* Don't allow a filtered frame to live forever.
*/
if (bf->bf_state.bfs_retries > SWMAX_RETRIES) {
sc->sc_stats.ast_tx_swretrymax++;
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX_FILT,
"%s: bf=%p, seqno=%d, exceeded retries\n",
__func__,
bf,
bf->bf_state.bfs_seqno);
return (0);
}
/*
* A busy buffer can't be added to the retry list.
* It needs to be cloned.
*/
if (bf->bf_flags & ATH_BUF_BUSY) {
nbf = ath_tx_retry_clone(sc, tid->an, tid, bf);
DPRINTF(sc, ATH_DEBUG_SW_TX_FILT,
"%s: busy buffer clone: %p -> %p\n",
__func__, bf, nbf);
} else {
nbf = bf;
}
if (nbf == NULL) {
DPRINTF(sc, ATH_DEBUG_SW_TX_FILT,
"%s: busy buffer couldn't be cloned (%p)!\n",
__func__, bf);
retval = 1;
} else {
ath_tx_tid_filt_comp_buf(sc, tid, nbf);
retval = 0;
}
ath_tx_tid_filt_comp_complete(sc, tid);
return (retval);
}
static void
ath_tx_tid_filt_comp_aggr(struct ath_softc *sc, struct ath_tid *tid,
struct ath_buf *bf_first, ath_bufhead *bf_q)
{
struct ath_buf *bf, *bf_next, *nbf;
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
bf = bf_first;
while (bf) {
bf_next = bf->bf_next;
bf->bf_next = NULL; /* Remove it from the aggr list */
/*
* Don't allow a filtered frame to live forever.
*/
if (bf->bf_state.bfs_retries > SWMAX_RETRIES) {
sc->sc_stats.ast_tx_swretrymax++;
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX_FILT,
"%s: bf=%p, seqno=%d, exceeded retries\n",
__func__,
bf,
bf->bf_state.bfs_seqno);
TAILQ_INSERT_TAIL(bf_q, bf, bf_list);
goto next;
}
if (bf->bf_flags & ATH_BUF_BUSY) {
nbf = ath_tx_retry_clone(sc, tid->an, tid, bf);
DPRINTF(sc, ATH_DEBUG_SW_TX_FILT,
"%s: busy buffer cloned: %p -> %p",
__func__, bf, nbf);
} else {
nbf = bf;
}
/*
* If the buffer couldn't be cloned, add it to bf_q;
* the caller will free the buffer(s) as required.
*/
if (nbf == NULL) {
DPRINTF(sc, ATH_DEBUG_SW_TX_FILT,
"%s: buffer couldn't be cloned! (%p)\n",
__func__, bf);
TAILQ_INSERT_TAIL(bf_q, bf, bf_list);
} else {
ath_tx_tid_filt_comp_buf(sc, tid, nbf);
}
next:
bf = bf_next;
}
ath_tx_tid_filt_comp_complete(sc, tid);
}
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
/*
* Suspend the queue because we need to TX a BAR.
*/
static void
ath_tx_tid_bar_suspend(struct ath_softc *sc, struct ath_tid *tid)
{
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX_BAR,
"%s: tid=%d, bar_wait=%d, bar_tx=%d, called\n",
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
__func__,
tid->tid,
tid->bar_wait,
tid->bar_tx);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
/* We shouldn't be called when bar_tx is 1 */
if (tid->bar_tx) {
DPRINTF(sc, ATH_DEBUG_SW_TX_BAR,
"%s: bar_tx is 1?!\n", __func__);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
}
/* If we've already been called, just be patient. */
if (tid->bar_wait)
return;
/* Wait! */
tid->bar_wait = 1;
/* Only one pause, no matter how many frames fail */
ath_tx_tid_pause(sc, tid);
}
/*
* We've finished with BAR handling - either we succeeded or
* failed. Either way, unsuspend TX.
*/
static void
ath_tx_tid_bar_unsuspend(struct ath_softc *sc, struct ath_tid *tid)
{
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX_BAR,
"%s: %6D: TID=%d, called\n",
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
__func__,
tid->an->an_node.ni_macaddr,
":",
tid->tid);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
if (tid->bar_tx == 0 || tid->bar_wait == 0) {
DPRINTF(sc, ATH_DEBUG_SW_TX_BAR,
"%s: %6D: TID=%d, bar_tx=%d, bar_wait=%d: ?\n",
__func__, tid->an->an_node.ni_macaddr, ":",
tid->tid, tid->bar_tx, tid->bar_wait);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
}
tid->bar_tx = tid->bar_wait = 0;
ath_tx_tid_resume(sc, tid);
}
/*
* Return whether we're ready to TX a BAR frame.
*
* Requires the TID lock be held.
*/
static int
ath_tx_tid_bar_tx_ready(struct ath_softc *sc, struct ath_tid *tid)
{
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
if (tid->bar_wait == 0 || tid->hwq_depth > 0)
return (0);
DPRINTF(sc, ATH_DEBUG_SW_TX_BAR,
"%s: %6D: TID=%d, bar ready\n",
__func__,
tid->an->an_node.ni_macaddr,
":",
tid->tid);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
return (1);
}
/*
* Check whether the current TID is ready to have a BAR
* TXed and if so, do the TX.
*
* Since the TID/TXQ lock can't be held during a call to
* ieee80211_send_bar(), we have to do the dirty thing of unlocking it,
* sending the BAR and locking it again.
*
* Eventually, the code to send the BAR should be broken out
* from this routine so the lock doesn't have to be reacquired
* just to be immediately dropped by the caller.
*/
static void
ath_tx_tid_bar_tx(struct ath_softc *sc, struct ath_tid *tid)
{
struct ieee80211_tx_ampdu *tap;
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX_BAR,
"%s: %6D: TID=%d, called\n",
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
__func__,
tid->an->an_node.ni_macaddr,
":",
tid->tid);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
tap = ath_tx_get_tx_tid(tid->an, tid->tid);
/*
* This is an error condition!
*/
if (tid->bar_wait == 0 || tid->bar_tx == 1) {
DPRINTF(sc, ATH_DEBUG_SW_TX_BAR,
"%s: %6D: TID=%d, bar_tx=%d, bar_wait=%d: ?\n",
__func__, tid->an->an_node.ni_macaddr, ":",
tid->tid, tid->bar_tx, tid->bar_wait);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
return;
}
/* Don't do anything if we still have pending frames */
if (tid->hwq_depth > 0) {
DPRINTF(sc, ATH_DEBUG_SW_TX_BAR,
"%s: %6D: TID=%d, hwq_depth=%d, waiting\n",
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
__func__,
tid->an->an_node.ni_macaddr,
":",
tid->tid,
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
tid->hwq_depth);
return;
}
/* We're now about to TX */
tid->bar_tx = 1;
/*
* Override the clrdmask configuration for the next frame,
* just to get the ball rolling.
*/
ath_tx_set_clrdmask(sc, tid->an);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
/*
* Calculate new BAW left edge, now that all frames have either
* succeeded or failed.
*
* XXX verify this is _actually_ the valid value to begin at!
*/
DPRINTF(sc, ATH_DEBUG_SW_TX_BAR,
"%s: %6D: TID=%d, new BAW left edge=%d\n",
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
__func__,
tid->an->an_node.ni_macaddr,
":",
tid->tid,
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
tap->txa_start);
/* Try sending the BAR frame */
/* We can't hold the lock here! */
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
if (ieee80211_send_bar(&tid->an->an_node, tap, tap->txa_start) == 0) {
/* Success? Now we wait for notification that it's done */
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
return;
}
/* Failure? For now, warn loudly and continue */
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
DPRINTF(sc, ATH_DEBUG_SW_TX_BAR,
"%s: %6D: TID=%d, failed to TX BAR, continue!\n",
__func__, tid->an->an_node.ni_macaddr, ":",
tid->tid);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
ath_tx_tid_bar_unsuspend(sc, tid);
}
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
static void
ath_tx_tid_drain_pkt(struct ath_softc *sc, struct ath_node *an,
struct ath_tid *tid, ath_bufhead *bf_cq, struct ath_buf *bf)
{
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/*
* If the current TID is running AMPDU, update
* the BAW.
*/
if (ath_tx_ampdu_running(sc, an, tid->tid) &&
bf->bf_state.bfs_dobaw) {
/*
* Only remove the frame from the BAW if it's
* been transmitted at least once; this means
* the frame was in the BAW to begin with.
*/
if (bf->bf_state.bfs_retries > 0) {
ath_tx_update_baw(sc, an, tid, bf);
bf->bf_state.bfs_dobaw = 0;
}
#if 0
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/*
* This has become a non-fatal error now
*/
if (! bf->bf_state.bfs_addedbaw)
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
"%s: wasn't added: seqno %d\n",
__func__, SEQNO(bf->bf_state.bfs_seqno));
#endif
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
}
Overhaul the TXQ locking (again!) as part of some beacon/cabq timing related issues. Moving the TX locking under one lock made things easier to progress on but it had one important side-effect - it increased the latency when handling CABQ setup when sending beacons. This commit introduces a bunch of new changes and a few unrelated changs that are just easier to lump in here. The aim is to have the CABQ locking separate from other locking. The CABQ transmit path in the beacon process thus doesn't have to grab the general TX lock, reducing lock contention/latency and making it more likely that we'll make the beacon TX timing. The second half of this commit is the CABQ related setup changes needed for sane looking EDMA CABQ support. Right now the EDMA TX code naively assumes that only one frame (MPDU or A-MPDU) is being pushed into each FIFO slot. For the CABQ this isn't true - a whole list of frames is being pushed in - and thus CABQ handling breaks very quickly. The aim here is to setup the CABQ list and then push _that list_ to the hardware for transmission. I can then extend the EDMA TX code to stamp that list as being "one" FIFO entry (likely by tagging the last buffer in that list as "FIFO END") so the EDMA TX completion code correctly tracks things. Major: * Migrate the per-TXQ add/removal locking back to per-TXQ, rather than a single lock. * Leave the software queue side of things under the ATH_TX_LOCK lock, (continuing) to serialise things as they are. * Add a new function which is called whenever there's a beacon miss, to print out some debugging. This is primarily designed to help me figure out if the beacon miss events are due to a noisy environment, issues with the PHY/MAC, or other. * Move the CABQ setup/enable to occur _after_ all the VAPs have been looked at. This means that for multiple VAPS in bursted mode, the CABQ gets primed once all VAPs are checked, rather than being primed on the first VAP and then having frames appended after this. Minor: * Add a (disabled) twiddle to let me enable/disable cabq traffic. It's primarily there to let me easily debug what's going on with beacon and CABQ setup/traffic; there's some DMA engine hangs which I'm finally trying to trace down. * Clear bf_next when flushing frames; it should quieten some warnings that show up when a node goes away. Tested: * AR9280, STA/hostap, up to 4 vaps (staggered) * AR5416, STA/hostap, up to 4 vaps (staggered) TODO: * (Lots) more AR9380 and later testing, as I may have missed something here. * Leverage this to fix CABQ hanling for AR9380 and later chips. * Force bursted beaconing on the chips that default to staggered beacons and ensure the CABQ stuff is all sane (eg, the MORE bits that aren't being correctly set when chaining descriptors.)
2013-03-24 00:03:12 +00:00
/* Strip it out of an aggregate list if it was in one */
bf->bf_next = NULL;
/* Insert on the free queue to be freed by the caller */
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
TAILQ_INSERT_TAIL(bf_cq, bf, bf_list);
}
static void
ath_tx_tid_drain_print(struct ath_softc *sc, struct ath_node *an,
const char *pfx, struct ath_tid *tid, struct ath_buf *bf)
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
{
struct ieee80211_node *ni = &an->an_node;
struct ath_txq *txq;
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
struct ieee80211_tx_ampdu *tap;
txq = sc->sc_ac2q[tid->ac];
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
tap = ath_tx_get_tx_tid(an, tid->tid);
DPRINTF(sc, ATH_DEBUG_SW_TX,
"%s: %s: %6D: bf=%p: addbaw=%d, dobaw=%d, "
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
"seqno=%d, retry=%d\n",
__func__,
pfx,
ni->ni_macaddr,
":",
bf,
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
bf->bf_state.bfs_addedbaw,
bf->bf_state.bfs_dobaw,
SEQNO(bf->bf_state.bfs_seqno),
bf->bf_state.bfs_retries);
DPRINTF(sc, ATH_DEBUG_SW_TX,
"%s: %s: %6D: bf=%p: txq[%d] axq_depth=%d, axq_aggr_depth=%d\n",
__func__,
pfx,
ni->ni_macaddr,
":",
bf,
txq->axq_qnum,
txq->axq_depth,
txq->axq_aggr_depth);
DPRINTF(sc, ATH_DEBUG_SW_TX,
"%s: %s: %6D: bf=%p: tid txq_depth=%d hwq_depth=%d, bar_wait=%d, "
"isfiltered=%d\n",
__func__,
pfx,
ni->ni_macaddr,
":",
bf,
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
tid->axq_depth,
tid->hwq_depth,
tid->bar_wait,
tid->isfiltered);
DPRINTF(sc, ATH_DEBUG_SW_TX,
"%s: %s: %6D: tid %d: "
"sched=%d, paused=%d, "
"incomp=%d, baw_head=%d, "
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
"baw_tail=%d txa_start=%d, ni_txseqs=%d\n",
__func__,
pfx,
ni->ni_macaddr,
":",
tid->tid,
tid->sched, tid->paused,
tid->incomp, tid->baw_head,
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
tid->baw_tail, tap == NULL ? -1 : tap->txa_start,
ni->ni_txseqs[tid->tid]);
/* XXX Dump the frame, see what it is? */
ieee80211_dump_pkt(ni->ni_ic,
mtod(bf->bf_m, const uint8_t *),
bf->bf_m->m_len, 0, -1);
}
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Free any packets currently pending in the software TX queue.
*
* This will be called when a node is being deleted.
*
* It can also be called on an active node during an interface
* reset or state transition.
*
* (From Linux/reference):
*
* TODO: For frame(s) that are in the retry state, we will reuse the
* sequence number(s) without setting the retry bit. The
* alternative is to give up on these and BAR the receiver's window
* forward.
*/
static void
ath_tx_tid_drain(struct ath_softc *sc, struct ath_node *an,
struct ath_tid *tid, ath_bufhead *bf_cq)
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
{
struct ath_buf *bf;
struct ieee80211_tx_ampdu *tap;
struct ieee80211_node *ni = &an->an_node;
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
int t;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
tap = ath_tx_get_tx_tid(an, tid->tid);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Walk the queue, free frames */
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
t = 0;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
for (;;) {
bf = ATH_TID_FIRST(tid);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (bf == NULL) {
break;
}
if (t == 0) {
ath_tx_tid_drain_print(sc, an, "norm", tid, bf);
t = 1;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
ATH_TID_REMOVE(tid, bf, bf_list);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
ath_tx_tid_drain_pkt(sc, an, tid, bf_cq, bf);
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/* And now, drain the filtered frame queue */
t = 0;
for (;;) {
bf = ATH_TID_FILT_FIRST(tid);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
if (bf == NULL)
break;
if (t == 0) {
ath_tx_tid_drain_print(sc, an, "filt", tid, bf);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
t = 1;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
ATH_TID_FILT_REMOVE(tid, bf, bf_list);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
ath_tx_tid_drain_pkt(sc, an, tid, bf_cq, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
/*
* Override the clrdmask configuration for the next frame
* in case there is some future transmission, just to get
* the ball rolling.
*
* This won't hurt things if the TID is about to be freed.
*/
ath_tx_set_clrdmask(sc, tid->an);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Now that it's completed, grab the TID lock and update
* the sequence number and BAW window.
* Because sequence numbers have been assigned to frames
* that haven't been sent yet, it's entirely possible
* we'll be called with some pending frames that have not
* been transmitted.
*
* The cleaner solution is to do the sequence number allocation
* when the packet is first transmitted - and thus the "retries"
* check above would be enough to update the BAW/seqno.
*/
/* But don't do it for non-QoS TIDs */
if (tap) {
#if 1
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX_CTRL,
"%s: %6D: node %p: TID %d: sliding BAW left edge to %d\n",
__func__,
ni->ni_macaddr,
":",
an,
tid->tid,
tap->txa_start);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
#endif
ni->ni_txseqs[tid->tid] = tap->txa_start;
tid->baw_tail = tid->baw_head;
}
}
/*
* Reset the TID state. This must be only called once the node has
* had its frames flushed from this TID, to ensure that no other
* pause / unpause logic can kick in.
*/
static void
ath_tx_tid_reset(struct ath_softc *sc, struct ath_tid *tid)
{
#if 0
tid->bar_wait = tid->bar_tx = tid->isfiltered = 0;
tid->paused = tid->sched = tid->addba_tx_pending = 0;
tid->incomp = tid->cleanup_inprogress = 0;
#endif
/*
* If we have a bar_wait set, we need to unpause the TID
* here. Otherwise once cleanup has finished, the TID won't
* have the right paused counter.
*
* XXX I'm not going through resume here - I don't want the
* node to be rescheuled just yet. This however should be
* methodized!
*/
if (tid->bar_wait) {
if (tid->paused > 0) {
tid->paused --;
}
}
/*
* XXX same with a currently filtered TID.
*
* Since this is being called during a flush, we assume that
* the filtered frame list is actually empty.
*
* XXX TODO: add in a check to ensure that the filtered queue
* depth is actually 0!
*/
if (tid->isfiltered) {
if (tid->paused > 0) {
tid->paused --;
}
}
/*
* Clear BAR, filtered frames, scheduled and ADDBA pending.
* The TID may be going through cleanup from the last association
* where things in the BAW are still in the hardware queue.
*/
tid->bar_wait = 0;
tid->bar_tx = 0;
tid->isfiltered = 0;
tid->sched = 0;
tid->addba_tx_pending = 0;
/*
* XXX TODO: it may just be enough to walk the HWQs and mark
* frames for that node as non-aggregate; or mark the ath_node
* with something that indicates that aggregation is no longer
* occuring. Then we can just toss the BAW complaints and
* do a complete hard reset of state here - no pause, no
* complete counter, etc.
*/
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Flush all software queued packets for the given node.
*
* This occurs when a completion handler frees the last buffer
* for a node, and the node is thus freed. This causes the node
* to be cleaned up, which ends up calling ath_tx_node_flush.
*/
void
ath_tx_node_flush(struct ath_softc *sc, struct ath_node *an)
{
int tid;
ath_bufhead bf_cq;
struct ath_buf *bf;
TAILQ_INIT(&bf_cq);
ATH_KTR(sc, ATH_KTR_NODE, 1, "ath_tx_node_flush: flush node; ni=%p",
&an->an_node);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
DPRINTF(sc, ATH_DEBUG_NODE,
"%s: %6D: flush; is_powersave=%d, stack_psq=%d, tim=%d, "
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
"swq_depth=%d, clrdmask=%d, leak_count=%d\n",
__func__,
an->an_node.ni_macaddr,
":",
an->an_is_powersave,
an->an_stack_psq,
an->an_tim_set,
an->an_swq_depth,
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
an->clrdmask,
an->an_leak_count);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
for (tid = 0; tid < IEEE80211_TID_SIZE; tid++) {
struct ath_tid *atid = &an->an_tid[tid];
/* Free packets */
ath_tx_tid_drain(sc, an, atid, &bf_cq);
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/* Remove this tid from the list of active tids */
ath_tx_tid_unsched(sc, atid);
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/* Reset the per-TID pause, BAR, etc state */
ath_tx_tid_reset(sc, atid);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* Clear global leak count
*/
an->an_leak_count = 0;
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Handle completed frames */
while ((bf = TAILQ_FIRST(&bf_cq)) != NULL) {
TAILQ_REMOVE(&bf_cq, bf, bf_list);
ath_tx_default_comp(sc, bf, 0);
}
}
/*
* Drain all the software TXQs currently with traffic queued.
*/
void
ath_tx_txq_drain(struct ath_softc *sc, struct ath_txq *txq)
{
struct ath_tid *tid;
ath_bufhead bf_cq;
struct ath_buf *bf;
TAILQ_INIT(&bf_cq);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Iterate over all active tids for the given txq,
* flushing and unsched'ing them
*/
while (! TAILQ_EMPTY(&txq->axq_tidq)) {
tid = TAILQ_FIRST(&txq->axq_tidq);
ath_tx_tid_drain(sc, tid->an, tid, &bf_cq);
ath_tx_tid_unsched(sc, tid);
}
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
while ((bf = TAILQ_FIRST(&bf_cq)) != NULL) {
TAILQ_REMOVE(&bf_cq, bf, bf_list);
ath_tx_default_comp(sc, bf, 0);
}
}
/*
* Handle completion of non-aggregate session frames.
*
* This (currently) doesn't implement software retransmission of
* non-aggregate frames!
*
* Software retransmission of non-aggregate frames needs to obey
* the strict sequence number ordering, and drop any frames that
* will fail this.
*
* For now, filtered frames and frame transmission will cause
* all kinds of issues. So we don't support them.
*
* So anyone queuing frames via ath_tx_normal_xmit() or
* ath_tx_hw_queue_norm() must override and set CLRDMASK.
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
*/
void
ath_tx_normal_comp(struct ath_softc *sc, struct ath_buf *bf, int fail)
{
struct ieee80211_node *ni = bf->bf_node;
struct ath_node *an = ATH_NODE(ni);
int tid = bf->bf_state.bfs_tid;
struct ath_tid *atid = &an->an_tid[tid];
struct ath_tx_status *ts = &bf->bf_status.ds_txstat;
/* The TID state is protected behind the TXQ lock */
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: bf=%p: fail=%d, hwq_depth now %d\n",
__func__, bf, fail, atid->hwq_depth - 1);
atid->hwq_depth--;
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
#if 0
/*
* If the frame was filtered, stick it on the filter frame
* queue and complain about it. It shouldn't happen!
*/
if ((ts->ts_status & HAL_TXERR_FILT) ||
(ts->ts_status != 0 && atid->isfiltered)) {
DPRINTF(sc, ATH_DEBUG_SW_TX,
"%s: isfiltered=%d, ts_status=%d: huh?\n",
__func__,
atid->isfiltered,
ts->ts_status);
ath_tx_tid_filt_comp_buf(sc, atid, bf);
}
#endif
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
if (atid->isfiltered)
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: filtered?!\n", __func__);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (atid->hwq_depth < 0)
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: hwq_depth < 0: %d\n",
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
__func__, atid->hwq_depth);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/*
* If the queue is filtered, potentially mark it as complete
* and reschedule it as needed.
*
* This is required as there may be a subsequent TX descriptor
* for this end-node that has CLRDMASK set, so it's quite possible
* that a filtered frame will be followed by a non-filtered
* (complete or otherwise) frame.
*
* XXX should we do this before we complete the frame?
*/
if (atid->isfiltered)
ath_tx_tid_filt_comp_complete(sc, atid);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* punt to rate control if we're not being cleaned up
* during a hw queue drain and the frame wanted an ACK.
*/
if (fail == 0 && ((bf->bf_state.bfs_txflags & HAL_TXDESC_NOACK) == 0))
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_update_ratectrl(sc, ni, bf->bf_state.bfs_rc,
ts, bf->bf_state.bfs_pktlen,
1, (ts->ts_status == 0) ? 0 : 1);
ath_tx_default_comp(sc, bf, fail);
}
/*
* Handle cleanup of aggregate session packets that aren't
* an A-MPDU.
*
* There's no need to update the BAW here - the session is being
* torn down.
*/
static void
ath_tx_comp_cleanup_unaggr(struct ath_softc *sc, struct ath_buf *bf)
{
struct ieee80211_node *ni = bf->bf_node;
struct ath_node *an = ATH_NODE(ni);
int tid = bf->bf_state.bfs_tid;
struct ath_tid *atid = &an->an_tid[tid];
DPRINTF(sc, ATH_DEBUG_SW_TX_CTRL, "%s: TID %d: incomp=%d\n",
__func__, tid, atid->incomp);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
atid->incomp--;
if (atid->incomp == 0) {
DPRINTF(sc, ATH_DEBUG_SW_TX_CTRL,
"%s: TID %d: cleaned up! resume!\n",
__func__, tid);
atid->cleanup_inprogress = 0;
ath_tx_tid_resume(sc, atid);
}
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_default_comp(sc, bf, 0);
}
/*
* Performs transmit side cleanup when TID changes from aggregated to
* unaggregated.
*
* - Discard all retry frames from the s/w queue.
* - Fix the tx completion function for all buffers in s/w queue.
* - Count the number of unacked frames, and let transmit completion
* handle it later.
*
* The caller is responsible for pausing the TID and unpausing the
* TID if no cleanup was required. Otherwise the cleanup path will
* unpause the TID once the last hardware queued frame is completed.
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
*/
static void
ath_tx_tid_cleanup(struct ath_softc *sc, struct ath_node *an, int tid,
ath_bufhead *bf_cq)
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
{
struct ath_tid *atid = &an->an_tid[tid];
struct ieee80211_tx_ampdu *tap;
struct ath_buf *bf, *bf_next;
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
"%s: TID %d: called\n", __func__, tid);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/*
* Move the filtered frames to the TX queue, before
* we run off and discard/process things.
*/
/* XXX this is really quite inefficient */
while ((bf = ATH_TID_FILT_LAST(atid, ath_bufhead_s)) != NULL) {
ATH_TID_FILT_REMOVE(atid, bf, bf_list);
ATH_TID_INSERT_HEAD(atid, bf, bf_list);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Update the frames in the software TX queue:
*
* + Discard retry frames in the queue
* + Fix the completion function to be non-aggregate
*/
bf = ATH_TID_FIRST(atid);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
while (bf) {
if (bf->bf_state.bfs_isretried) {
bf_next = TAILQ_NEXT(bf, bf_list);
ATH_TID_REMOVE(atid, bf, bf_list);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (bf->bf_state.bfs_dobaw) {
ath_tx_update_baw(sc, an, atid, bf);
if (!bf->bf_state.bfs_addedbaw)
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
"%s: wasn't added: seqno %d\n",
__func__,
SEQNO(bf->bf_state.bfs_seqno));
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
bf->bf_state.bfs_dobaw = 0;
/*
* Call the default completion handler with "fail" just
* so upper levels are suitably notified about this.
*/
TAILQ_INSERT_TAIL(bf_cq, bf, bf_list);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
bf = bf_next;
continue;
}
/* Give these the default completion handler */
bf->bf_comp = ath_tx_normal_comp;
bf = TAILQ_NEXT(bf, bf_list);
}
/*
* Calculate what hardware-queued frames exist based
* on the current BAW size. Ie, what frames have been
* added to the TX hardware queue for this TID but
* not yet ACKed.
*/
tap = ath_tx_get_tx_tid(an, tid);
/* Need the lock - fiddling with BAW */
while (atid->baw_head != atid->baw_tail) {
if (atid->tx_buf[atid->baw_head]) {
atid->incomp++;
atid->cleanup_inprogress = 1;
atid->tx_buf[atid->baw_head] = NULL;
}
INCR(atid->baw_head, ATH_TID_MAX_BUFS);
INCR(tap->txa_start, IEEE80211_SEQ_RANGE);
}
if (atid->cleanup_inprogress)
DPRINTF(sc, ATH_DEBUG_SW_TX_CTRL,
"%s: TID %d: cleanup needed: %d packets\n",
__func__, tid, atid->incomp);
/* Owner now must free completed frames */
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
static struct ath_buf *
ath_tx_retry_clone(struct ath_softc *sc, struct ath_node *an,
struct ath_tid *tid, struct ath_buf *bf)
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
{
struct ath_buf *nbf;
int error;
/*
* Clone the buffer. This will handle the dma unmap and
* copy the node reference to the new buffer. If this
* works out, 'bf' will have no DMA mapping, no mbuf
* pointer and no node reference.
*/
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
nbf = ath_buf_clone(sc, bf);
#if 0
DPRINTF(sc, ATH_DEBUG_XMIT, "%s: ATH_BUF_BUSY; cloning\n",
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
__func__);
#endif
if (nbf == NULL) {
/* Failed to clone */
DPRINTF(sc, ATH_DEBUG_XMIT,
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
"%s: failed to clone a busy buffer\n",
__func__);
return NULL;
}
/* Setup the dma for the new buffer */
error = ath_tx_dmasetup(sc, nbf, nbf->bf_m);
if (error != 0) {
DPRINTF(sc, ATH_DEBUG_XMIT,
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
"%s: failed to setup dma for clone\n",
__func__);
/*
* Put this at the head of the list, not tail;
* that way it doesn't interfere with the
* busy buffer logic (which uses the tail of
* the list.)
*/
ATH_TXBUF_LOCK(sc);
ath_returnbuf_head(sc, nbf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ATH_TXBUF_UNLOCK(sc);
return NULL;
}
/* Update BAW if required, before we free the original buf */
if (bf->bf_state.bfs_dobaw)
ath_tx_switch_baw_buf(sc, an, tid, bf, nbf);
/* Free original buffer; return new buffer */
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_freebuf(sc, bf);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
return nbf;
}
/*
* Handle retrying an unaggregate frame in an aggregate
* session.
*
* If too many retries occur, pause the TID, wait for
* any further retransmits (as there's no reason why
* non-aggregate frames in an aggregate session are
* transmitted in-order; they just have to be in-BAW)
* and then queue a BAR.
*/
static void
ath_tx_aggr_retry_unaggr(struct ath_softc *sc, struct ath_buf *bf)
{
struct ieee80211_node *ni = bf->bf_node;
struct ath_node *an = ATH_NODE(ni);
int tid = bf->bf_state.bfs_tid;
struct ath_tid *atid = &an->an_tid[tid];
struct ieee80211_tx_ampdu *tap;
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
tap = ath_tx_get_tx_tid(an, tid);
/*
* If the buffer is marked as busy, we can't directly
* reuse it. Instead, try to clone the buffer.
* If the clone is successful, recycle the old buffer.
* If the clone is unsuccessful, set bfs_retries to max
* to force the next bit of code to free the buffer
* for us.
*/
if ((bf->bf_state.bfs_retries < SWMAX_RETRIES) &&
(bf->bf_flags & ATH_BUF_BUSY)) {
struct ath_buf *nbf;
nbf = ath_tx_retry_clone(sc, an, atid, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (nbf)
/* bf has been freed at this point */
bf = nbf;
else
bf->bf_state.bfs_retries = SWMAX_RETRIES + 1;
}
if (bf->bf_state.bfs_retries >= SWMAX_RETRIES) {
DPRINTF(sc, ATH_DEBUG_SW_TX_RETRIES,
"%s: exceeded retries; seqno %d\n",
__func__, SEQNO(bf->bf_state.bfs_seqno));
sc->sc_stats.ast_tx_swretrymax++;
/* Update BAW anyway */
if (bf->bf_state.bfs_dobaw) {
ath_tx_update_baw(sc, an, atid, bf);
if (! bf->bf_state.bfs_addedbaw)
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
"%s: wasn't added: seqno %d\n",
__func__, SEQNO(bf->bf_state.bfs_seqno));
}
bf->bf_state.bfs_dobaw = 0;
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
/* Suspend the TX queue and get ready to send the BAR */
ath_tx_tid_bar_suspend(sc, atid);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
/* Send the BAR if there are no other frames waiting */
if (ath_tx_tid_bar_tx_ready(sc, atid))
ath_tx_tid_bar_tx(sc, atid);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Free buffer, bf is free after this call */
ath_tx_default_comp(sc, bf, 0);
return;
}
/*
* This increments the retry counter as well as
* sets the retry flag in the ath_buf and packet
* body.
*/
ath_tx_set_retry(sc, bf);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
sc->sc_stats.ast_tx_swretries++;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Insert this at the head of the queue, so it's
* retried before any current/subsequent frames.
*/
ATH_TID_INSERT_HEAD(atid, bf, bf_list);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_tid_sched(sc, atid);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
/* Send the BAR if there are no other frames waiting */
if (ath_tx_tid_bar_tx_ready(sc, atid))
ath_tx_tid_bar_tx(sc, atid);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
/*
* Common code for aggregate excessive retry/subframe retry.
* If retrying, queues buffers to bf_q. If not, frees the
* buffers.
*
* XXX should unify this with ath_tx_aggr_retry_unaggr()
*/
static int
ath_tx_retry_subframe(struct ath_softc *sc, struct ath_buf *bf,
ath_bufhead *bf_q)
{
struct ieee80211_node *ni = bf->bf_node;
struct ath_node *an = ATH_NODE(ni);
int tid = bf->bf_state.bfs_tid;
struct ath_tid *atid = &an->an_tid[tid];
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* XXX clr11naggr should be done for all subframes */
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_hal_clr11n_aggr(sc->sc_ah, bf->bf_desc);
ath_hal_set11nburstduration(sc->sc_ah, bf->bf_desc, 0);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* ath_hal_set11n_virtualmorefrag(sc->sc_ah, bf->bf_desc, 0); */
/*
* If the buffer is marked as busy, we can't directly
* reuse it. Instead, try to clone the buffer.
* If the clone is successful, recycle the old buffer.
* If the clone is unsuccessful, set bfs_retries to max
* to force the next bit of code to free the buffer
* for us.
*/
if ((bf->bf_state.bfs_retries < SWMAX_RETRIES) &&
(bf->bf_flags & ATH_BUF_BUSY)) {
struct ath_buf *nbf;
nbf = ath_tx_retry_clone(sc, an, atid, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (nbf)
/* bf has been freed at this point */
bf = nbf;
else
bf->bf_state.bfs_retries = SWMAX_RETRIES + 1;
}
if (bf->bf_state.bfs_retries >= SWMAX_RETRIES) {
sc->sc_stats.ast_tx_swretrymax++;
DPRINTF(sc, ATH_DEBUG_SW_TX_RETRIES,
"%s: max retries: seqno %d\n",
__func__, SEQNO(bf->bf_state.bfs_seqno));
ath_tx_update_baw(sc, an, atid, bf);
if (!bf->bf_state.bfs_addedbaw)
DPRINTF(sc, ATH_DEBUG_SW_TX_BAW,
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
"%s: wasn't added: seqno %d\n",
__func__, SEQNO(bf->bf_state.bfs_seqno));
bf->bf_state.bfs_dobaw = 0;
return 1;
}
ath_tx_set_retry(sc, bf);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
sc->sc_stats.ast_tx_swretries++;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
bf->bf_next = NULL; /* Just to make sure */
/* Clear the aggregate state */
bf->bf_state.bfs_aggr = 0;
bf->bf_state.bfs_ndelim = 0; /* ??? needed? */
bf->bf_state.bfs_nframes = 1;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
TAILQ_INSERT_TAIL(bf_q, bf, bf_list);
return 0;
}
/*
* error pkt completion for an aggregate destination
*/
static void
ath_tx_comp_aggr_error(struct ath_softc *sc, struct ath_buf *bf_first,
struct ath_tid *tid)
{
struct ieee80211_node *ni = bf_first->bf_node;
struct ath_node *an = ATH_NODE(ni);
struct ath_buf *bf_next, *bf;
ath_bufhead bf_q;
int drops = 0;
struct ieee80211_tx_ampdu *tap;
ath_bufhead bf_cq;
TAILQ_INIT(&bf_q);
TAILQ_INIT(&bf_cq);
/*
* Update rate control - all frames have failed.
*
* XXX use the length in the first frame in the series;
* XXX just so things are consistent for now.
*/
ath_tx_update_ratectrl(sc, ni, bf_first->bf_state.bfs_rc,
&bf_first->bf_status.ds_txstat,
bf_first->bf_state.bfs_pktlen,
bf_first->bf_state.bfs_nframes, bf_first->bf_state.bfs_nframes);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
tap = ath_tx_get_tx_tid(an, tid->tid);
sc->sc_stats.ast_tx_aggr_failall++;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Retry all subframes */
bf = bf_first;
while (bf) {
bf_next = bf->bf_next;
bf->bf_next = NULL; /* Remove it from the aggr list */
sc->sc_stats.ast_tx_aggr_fail++;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (ath_tx_retry_subframe(sc, bf, &bf_q)) {
drops++;
bf->bf_next = NULL;
TAILQ_INSERT_TAIL(&bf_cq, bf, bf_list);
}
bf = bf_next;
}
/* Prepend all frames to the beginning of the queue */
while ((bf = TAILQ_LAST(&bf_q, ath_bufhead_s)) != NULL) {
TAILQ_REMOVE(&bf_q, bf, bf_list);
ATH_TID_INSERT_HEAD(tid, bf, bf_list);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
/*
* Schedule the TID to be re-tried.
*/
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_tid_sched(sc, tid);
/*
* send bar if we dropped any frames
*
* Keep the txq lock held for now, as we need to ensure
* that ni_txseqs[] is consistent (as it's being updated
* in the ifnet TX context or raw TX context.)
*/
if (drops) {
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
/* Suspend the TX queue and get ready to send the BAR */
ath_tx_tid_bar_suspend(sc, tid);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
/*
* Send BAR if required
*/
if (ath_tx_tid_bar_tx_ready(sc, tid))
ath_tx_tid_bar_tx(sc, tid);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Complete frames which errored out */
while ((bf = TAILQ_FIRST(&bf_cq)) != NULL) {
TAILQ_REMOVE(&bf_cq, bf, bf_list);
ath_tx_default_comp(sc, bf, 0);
}
}
/*
* Handle clean-up of packets from an aggregate list.
*
* There's no need to update the BAW here - the session is being
* torn down.
*/
static void
ath_tx_comp_cleanup_aggr(struct ath_softc *sc, struct ath_buf *bf_first)
{
struct ath_buf *bf, *bf_next;
struct ieee80211_node *ni = bf_first->bf_node;
struct ath_node *an = ATH_NODE(ni);
int tid = bf_first->bf_state.bfs_tid;
struct ath_tid *atid = &an->an_tid[tid];
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* update incomp */
bf = bf_first;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
while (bf) {
atid->incomp--;
bf = bf->bf_next;
}
if (atid->incomp == 0) {
DPRINTF(sc, ATH_DEBUG_SW_TX_CTRL,
"%s: TID %d: cleaned up! resume!\n",
__func__, tid);
atid->cleanup_inprogress = 0;
ath_tx_tid_resume(sc, atid);
}
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
/* Send BAR if required */
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/* XXX why would we send a BAR when transitioning to non-aggregation? */
/*
* XXX TODO: we should likely just tear down the BAR state here,
* rather than sending a BAR.
*/
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
if (ath_tx_tid_bar_tx_ready(sc, atid))
ath_tx_tid_bar_tx(sc, atid);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Handle frame completion */
bf = bf_first;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
while (bf) {
bf_next = bf->bf_next;
ath_tx_default_comp(sc, bf, 1);
bf = bf_next;
}
}
/*
* Handle completion of an set of aggregate frames.
*
* Note: the completion handler is the last descriptor in the aggregate,
* not the last descriptor in the first frame.
*/
static void
ath_tx_aggr_comp_aggr(struct ath_softc *sc, struct ath_buf *bf_first,
int fail)
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
{
//struct ath_desc *ds = bf->bf_lastds;
struct ieee80211_node *ni = bf_first->bf_node;
struct ath_node *an = ATH_NODE(ni);
int tid = bf_first->bf_state.bfs_tid;
struct ath_tid *atid = &an->an_tid[tid];
struct ath_tx_status ts;
struct ieee80211_tx_ampdu *tap;
ath_bufhead bf_q;
ath_bufhead bf_cq;
int seq_st, tx_ok;
int hasba, isaggr;
uint32_t ba[2];
struct ath_buf *bf, *bf_next;
int ba_index;
int drops = 0;
int nframes = 0, nbad = 0, nf;
int pktlen;
/* XXX there's too much on the stack? */
2012-05-26 01:35:11 +00:00
struct ath_rc_series rc[ATH_RC_NUM];
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
int txseq;
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR, "%s: called; hwq_depth=%d\n",
__func__, atid->hwq_depth);
/*
* Take a copy; this may be needed -after- bf_first
* has been completed and freed.
*/
ts = bf_first->bf_status.ds_txstat;
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
TAILQ_INIT(&bf_q);
TAILQ_INIT(&bf_cq);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* The TID state is kept behind the TXQ lock */
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
atid->hwq_depth--;
if (atid->hwq_depth < 0)
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR, "%s: hwq_depth < 0: %d\n",
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
__func__, atid->hwq_depth);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/*
* If the TID is filtered, handle completing the filter
* transition before potentially kicking it to the cleanup
* function.
*
* XXX this is duplicate work, ew.
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
*/
if (atid->isfiltered)
ath_tx_tid_filt_comp_complete(sc, atid);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Punt cleanup to the relevant function, not our problem now
*/
if (atid->cleanup_inprogress) {
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
if (atid->isfiltered)
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
"%s: isfiltered=1, normal_comp?\n",
__func__);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_comp_cleanup_aggr(sc, bf_first);
return;
}
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/*
* If the frame is filtered, transition to filtered frame
* mode and add this to the filtered frame list.
*
* XXX TODO: figure out how this interoperates with
* BAR, pause and cleanup states.
*/
if ((ts.ts_status & HAL_TXERR_FILT) ||
(ts.ts_status != 0 && atid->isfiltered)) {
if (fail != 0)
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
"%s: isfiltered=1, fail=%d\n", __func__, fail);
ath_tx_tid_filt_comp_aggr(sc, atid, bf_first, &bf_cq);
/* Remove from BAW */
TAILQ_FOREACH_SAFE(bf, &bf_cq, bf_list, bf_next) {
if (bf->bf_state.bfs_addedbaw)
drops++;
if (bf->bf_state.bfs_dobaw) {
ath_tx_update_baw(sc, an, atid, bf);
if (!bf->bf_state.bfs_addedbaw)
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
"%s: wasn't added: seqno %d\n",
__func__,
SEQNO(bf->bf_state.bfs_seqno));
}
bf->bf_state.bfs_dobaw = 0;
}
/*
* If any intermediate frames in the BAW were dropped when
* handling filtering things, send a BAR.
*/
if (drops)
ath_tx_tid_bar_suspend(sc, atid);
/*
* Finish up by sending a BAR if required and freeing
* the frames outside of the TX lock.
*/
goto finish_send_bar;
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* XXX for now, use the first frame in the aggregate for
* XXX rate control completion; it's at least consistent.
*/
pktlen = bf_first->bf_state.bfs_pktlen;
/*
* Handle errors first!
*
* Here, handle _any_ error as a "exceeded retries" error.
* Later on (when filtered frames are to be specially handled)
* it'll have to be expanded.
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
*/
#if 0
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (ts.ts_status & HAL_TXERR_XRETRY) {
#endif
if (ts.ts_status != 0) {
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_comp_aggr_error(sc, bf_first, atid);
return;
}
tap = ath_tx_get_tx_tid(an, tid);
/*
* extract starting sequence and block-ack bitmap
*/
/* XXX endian-ness of seq_st, ba? */
seq_st = ts.ts_seqnum;
hasba = !! (ts.ts_flags & HAL_TX_BA);
tx_ok = (ts.ts_status == 0);
isaggr = bf_first->bf_state.bfs_aggr;
ba[0] = ts.ts_ba_low;
ba[1] = ts.ts_ba_high;
/*
* Copy the TX completion status and the rate control
* series from the first descriptor, as it may be freed
* before the rate control code can get its grubby fingers
* into things.
*/
memcpy(rc, bf_first->bf_state.bfs_rc, sizeof(rc));
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
"%s: txa_start=%d, tx_ok=%d, status=%.8x, flags=%.8x, "
"isaggr=%d, seq_st=%d, hasba=%d, ba=%.8x, %.8x\n",
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
__func__, tap->txa_start, tx_ok, ts.ts_status, ts.ts_flags,
isaggr, seq_st, hasba, ba[0], ba[1]);
/*
* The reference driver doesn't do this; it simply ignores
* this check in its entirety.
*
* I've seen this occur when using iperf to send traffic
* out tid 1 - the aggregate frames are all marked as TID 1,
* but the TXSTATUS has TID=0. So, let's just ignore this
* check.
*/
#if 0
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Occasionally, the MAC sends a tx status for the wrong TID. */
if (tid != ts.ts_tid) {
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR, "%s: tid %d != hw tid %d\n",
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
__func__, tid, ts.ts_tid);
tx_ok = 0;
}
#endif
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* AR5416 BA bug; this requires an interface reset */
if (isaggr && tx_ok && (! hasba)) {
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
"%s: AR5416 bug: hasba=%d; txok=%d, isaggr=%d, "
"seq_st=%d\n",
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
__func__, hasba, tx_ok, isaggr, seq_st);
/* XXX TODO: schedule an interface reset */
#ifdef ATH_DEBUG
ath_printtxbuf(sc, bf_first,
sc->sc_ac2q[atid->ac]->axq_qnum, 0, 0);
#endif
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
/*
* Walk the list of frames, figure out which ones were correctly
* sent and which weren't.
*/
bf = bf_first;
nf = bf_first->bf_state.bfs_nframes;
/* bf_first is going to be invalid once this list is walked */
bf_first = NULL;
/*
* Walk the list of completed frames and determine
* which need to be completed and which need to be
* retransmitted.
*
* For completed frames, the completion functions need
* to be called at the end of this function as the last
* node reference may free the node.
*
* Finally, since the TXQ lock can't be held during the
* completion callback (to avoid lock recursion),
* the completion calls have to be done outside of the
* lock.
*/
while (bf) {
nframes++;
ba_index = ATH_BA_INDEX(seq_st,
SEQNO(bf->bf_state.bfs_seqno));
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
bf_next = bf->bf_next;
bf->bf_next = NULL; /* Remove it from the aggr list */
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
"%s: checking bf=%p seqno=%d; ack=%d\n",
__func__, bf, SEQNO(bf->bf_state.bfs_seqno),
ATH_BA_ISSET(ba, ba_index));
if (tx_ok && ATH_BA_ISSET(ba, ba_index)) {
sc->sc_stats.ast_tx_aggr_ok++;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_update_baw(sc, an, atid, bf);
bf->bf_state.bfs_dobaw = 0;
if (!bf->bf_state.bfs_addedbaw)
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
"%s: wasn't added: seqno %d\n",
__func__, SEQNO(bf->bf_state.bfs_seqno));
bf->bf_next = NULL;
TAILQ_INSERT_TAIL(&bf_cq, bf, bf_list);
} else {
sc->sc_stats.ast_tx_aggr_fail++;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (ath_tx_retry_subframe(sc, bf, &bf_q)) {
drops++;
bf->bf_next = NULL;
TAILQ_INSERT_TAIL(&bf_cq, bf, bf_list);
}
nbad++;
}
bf = bf_next;
}
/*
* Now that the BAW updates have been done, unlock
*
* txseq is grabbed before the lock is released so we
* have a consistent view of what -was- in the BAW.
* Anything after this point will not yet have been
* TXed.
*/
txseq = tap->txa_start;
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (nframes != nf)
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
"%s: num frames seen=%d; bf nframes=%d\n",
__func__, nframes, nf);
/*
* Now we know how many frames were bad, call the rate
* control code.
*/
if (fail == 0)
ath_tx_update_ratectrl(sc, ni, rc, &ts, pktlen, nframes,
nbad);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* send bar if we dropped any frames
*/
if (drops) {
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
/* Suspend the TX queue and get ready to send the BAR */
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
ath_tx_tid_bar_suspend(sc, atid);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
"%s: txa_start now %d\n", __func__, tap->txa_start);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
/* Prepend all frames to the beginning of the queue */
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
while ((bf = TAILQ_LAST(&bf_q, ath_bufhead_s)) != NULL) {
TAILQ_REMOVE(&bf_q, bf, bf_list);
ATH_TID_INSERT_HEAD(atid, bf, bf_list);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
/*
* Reschedule to grab some further frames.
*/
ath_tx_tid_sched(sc, atid);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/*
* If the queue is filtered, re-schedule as required.
*
* This is required as there may be a subsequent TX descriptor
* for this end-node that has CLRDMASK set, so it's quite possible
* that a filtered frame will be followed by a non-filtered
* (complete or otherwise) frame.
*
* XXX should we do this before we complete the frame?
*/
if (atid->isfiltered)
ath_tx_tid_filt_comp_complete(sc, atid);
finish_send_bar:
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
/*
* Send BAR if required
*/
if (ath_tx_tid_bar_tx_ready(sc, atid))
ath_tx_tid_bar_tx(sc, atid);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Do deferred completion */
while ((bf = TAILQ_FIRST(&bf_cq)) != NULL) {
TAILQ_REMOVE(&bf_cq, bf, bf_list);
ath_tx_default_comp(sc, bf, 0);
}
}
/*
* Handle completion of unaggregated frames in an ADDBA
* session.
*
* Fail is set to 1 if the entry is being freed via a call to
* ath_tx_draintxq().
*/
static void
ath_tx_aggr_comp_unaggr(struct ath_softc *sc, struct ath_buf *bf, int fail)
{
struct ieee80211_node *ni = bf->bf_node;
struct ath_node *an = ATH_NODE(ni);
int tid = bf->bf_state.bfs_tid;
struct ath_tid *atid = &an->an_tid[tid];
struct ath_tx_status ts;
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
int drops = 0;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Take a copy of this; filtering/cloning the frame may free the
* bf pointer.
*/
ts = bf->bf_status.ds_txstat;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Update rate control status here, before we possibly
* punt to retry or cleanup.
*
* Do it outside of the TXQ lock.
*/
if (fail == 0 && ((bf->bf_state.bfs_txflags & HAL_TXDESC_NOACK) == 0))
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_update_ratectrl(sc, ni, bf->bf_state.bfs_rc,
&bf->bf_status.ds_txstat,
bf->bf_state.bfs_pktlen,
1, (ts.ts_status == 0) ? 0 : 1);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* This is called early so atid->hwq_depth can be tracked.
* This unfortunately means that it's released and regrabbed
* during retry and cleanup. That's rather inefficient.
*/
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (tid == IEEE80211_NONQOS_TID)
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: TID=16!\n", __func__);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX,
"%s: bf=%p: tid=%d, hwq_depth=%d, seqno=%d\n",
__func__, bf, bf->bf_state.bfs_tid, atid->hwq_depth,
SEQNO(bf->bf_state.bfs_seqno));
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
atid->hwq_depth--;
if (atid->hwq_depth < 0)
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: hwq_depth < 0: %d\n",
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
__func__, atid->hwq_depth);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/*
* If the TID is filtered, handle completing the filter
* transition before potentially kicking it to the cleanup
* function.
*/
if (atid->isfiltered)
ath_tx_tid_filt_comp_complete(sc, atid);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* If a cleanup is in progress, punt to comp_cleanup;
* rather than handling it here. It's thus their
* responsibility to clean up, call the completion
* function in net80211, etc.
*/
if (atid->cleanup_inprogress) {
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
if (atid->isfiltered)
DPRINTF(sc, ATH_DEBUG_SW_TX,
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
"%s: isfiltered=1, normal_comp?\n",
__func__);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: cleanup_unaggr\n",
__func__);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_comp_cleanup_unaggr(sc, bf);
return;
}
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/*
* XXX TODO: how does cleanup, BAR and filtered frame handling
* overlap?
*
* If the frame is filtered OR if it's any failure but
* the TID is filtered, the frame must be added to the
* filtered frame list.
*
* However - a busy buffer can't be added to the filtered
* list as it will end up being recycled without having
* been made available for the hardware.
*/
if ((ts.ts_status & HAL_TXERR_FILT) ||
(ts.ts_status != 0 && atid->isfiltered)) {
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
int freeframe;
if (fail != 0)
DPRINTF(sc, ATH_DEBUG_SW_TX,
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
"%s: isfiltered=1, fail=%d\n",
__func__, fail);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
freeframe = ath_tx_tid_filt_comp_single(sc, atid, bf);
if (freeframe) {
/* Remove from BAW */
if (bf->bf_state.bfs_addedbaw)
drops++;
if (bf->bf_state.bfs_dobaw) {
ath_tx_update_baw(sc, an, atid, bf);
if (!bf->bf_state.bfs_addedbaw)
DPRINTF(sc, ATH_DEBUG_SW_TX,
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
"%s: wasn't added: seqno %d\n",
__func__, SEQNO(bf->bf_state.bfs_seqno));
}
bf->bf_state.bfs_dobaw = 0;
}
/*
* If the frame couldn't be filtered, treat it as a drop and
* prepare to send a BAR.
*/
if (freeframe && drops)
ath_tx_tid_bar_suspend(sc, atid);
/*
* Send BAR if required
*/
if (ath_tx_tid_bar_tx_ready(sc, atid))
ath_tx_tid_bar_tx(sc, atid);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/*
* If freeframe is set, then the frame couldn't be
* cloned and bf is still valid. Just complete/free it.
*/
if (freeframe)
ath_tx_default_comp(sc, bf, fail);
return;
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Don't bother with the retry check if all frames
* are being failed (eg during queue deletion.)
*/
#if 0
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (fail == 0 && ts->ts_status & HAL_TXERR_XRETRY) {
#endif
if (fail == 0 && ts.ts_status != 0) {
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: retry_unaggr\n",
__func__);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_aggr_retry_unaggr(sc, bf);
return;
}
/* Success? Complete */
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: TID=%d, seqno %d\n",
__func__, tid, SEQNO(bf->bf_state.bfs_seqno));
if (bf->bf_state.bfs_dobaw) {
ath_tx_update_baw(sc, an, atid, bf);
bf->bf_state.bfs_dobaw = 0;
if (!bf->bf_state.bfs_addedbaw)
DPRINTF(sc, ATH_DEBUG_SW_TX,
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
"%s: wasn't added: seqno %d\n",
__func__, SEQNO(bf->bf_state.bfs_seqno));
}
Implement my first cut at filtered frames in aggregation sessions. The hardware can optionally "filter" frames if successive transmissions to a given node (ie, "entry in the keycache") fail. That way the hardware can implement a kind of early abort of all the other frames queued to that destination, rather than simply trying to TX each frame to that destination (and failing.) The background: * If a frame comes back as being filtered, the hardware didn't try to TX it (or it was outside the TX burst opportunity.) So, take it as a hint that some (but not all, see below) frames to the destination may be filtered. * If the CLRDMASK bit is set in a TX descriptor, the "filter to this destination" bit in the keycache entry is cleared and TX to that host will be unconditionally retried. * Right now everything has the CLRDMASK bit set, so filtered frames tend to be aggregates and frames that fall outside of the WME burst window. It was a bit worse in the past as I had messed up the TX flags and CLRDMASK wasn't being set on aggregate frames. The annoying bits: * It's easy (ish) to do for aggregate session frames - firstly, they can be retried in any order as long as they're within the BAW, and there's already a bunch of infrastructure tracking how many frames the TID has queued to the hardware (tid->hwq_depth.) However, for frames that bypassed the software queue, hwq_depth doesn't get incremented. I'll fix that in a subsequent commit. * For non-aggregate session frames, the only retries that can occur are ones for sequence numbers that hvaen't successfully been TXed yet. Since there's no re-ordering going on in non-aggregate sessions, if any subsequent seqno frames make it out, any filtered frames before that seqno need to be dropped. Hence why this initially is just for aggregate session frames. * Since there may be intermediary frames to the destination that have CLRDMASK set - for example, any directly dispatched management frames to that destination - it's possible that there will be some filtered frames followed up by some non filtered frames. Thus, it can't be assumed that once you see a filtered frame for the given destination node, all subsequent frames for all TIDs will be filtered. Ok, with that in mind: * Create a per-TID filtered frame queue for frames that the hardware returns as filtered. * Track filtered frames per-tid, rather than per-node. It just makes the locking much easier. * When a filtered frame appears in the completion function, the node transitions to "filtered", and all subsequent completed error frames (filtered or otherwise) are put on the filtered frame queue. The TID is paused once (during the transition from non-filtered to filtered). * If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be sent. * Once all the frames queued to the hardware for the given filtered frame TID, transition back from filtered frame to non-filtered frame, which means pre-pending all the filtered frames onto the head of the software queue, clearing the filtered frame state and unpausing the TID. Things get quite hairy around handling completion (aggr, non-aggr, norm, direct-dispatched frames to a hardware queue); whether it's an "error", "cleanup" or "BAR" state as well as filtered, which order to do things in (eg do filtered BEFORE checking for BAR, as the filter completion may be needed to actually transmit a BAR frame.) This work has definitely reminded me that I have to tidy up all the locking and remove some of the ridiculous lock/unlock/lock/unlock going on in the completion functions. It's also reminded me that I should really split out TID versus hardware TXQ locking, even if the underlying locking is still the destination hardware TXQ. Finally, this is all pre-requisite for working on AP mode power save support (PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as they can transition into filter mode, stopping any TX until everything has caught up.) Finally (ish) - this should also be done for non-aggregate sessions as there are still plenty of laptops and mobile devices that don't speak 802.11n but do wish for stable, useful power save AP support where packets aren't simply dropped. This requires software retransmission for non-aggregate sessions to be implemented, which includes the caveats I've mentioned above. Finally finally - this doesn't yet do anything about the CLRDMASK bit in the TX descriptor. That's still unconditionally set to 1. I'll debug the current work (mostly ensuring I haven't busted up the hairy transitions between BAR, filtered, error (all frames in an aggregate failing) and cleanup (when transitioning from aggregation -> non-aggregation.)) Finally finally finally - this is all original work by yours truely, rather than ported from the Atheros internal driver codebase or Linux ath9k. Tested: * AR9280, AR5416 in STA mode * AR9280, AR9130 in hostap mode * Lots and lots of iperf testing in very marginal and non-marginal conditions, complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
/*
* If the queue is filtered, re-schedule as required.
*
* This is required as there may be a subsequent TX descriptor
* for this end-node that has CLRDMASK set, so it's quite possible
* that a filtered frame will be followed by a non-filtered
* (complete or otherwise) frame.
*
* XXX should we do this before we complete the frame?
*/
if (atid->isfiltered)
ath_tx_tid_filt_comp_complete(sc, atid);
Implement BAR TX. A BAR frame must be transmitted when an frame in an A-MPDU session fails to transmit - it's retried too often, or it can't be cloned for re-transmission. The BAR frame tells the remote side to advance the left edge of the block-ack window (BAW) to a new value. In order to do this: * TX for that particular node/TID must be paused; * The existing frames in the hardware queue needs to be completed, whether they're TXed successfully or otherwise; * The new left edge of the BAW is then communicated to the remote side via a BAR frame; * Once the BAR frame has been sucessfully TXed, aggregation can resume; * If the BAR frame can't be successfully TXed, the aggregation session is torn down. This is a first pass that implements the above. What needs to be done/ tested: * What happens during say, a channel reset / stuck beacon _and_ BAR TX. It _should_ be correctly buffered and retried once the reset has completed. But if a bgscan occurs (and they shouldn't, grr) the BAR frame will be forcibly failed and the aggregation session will be torn down. Yes, another reason to disable bgscan until I've figured this out. * There's way too much locking going on here. I'm going to do a couple of further passes of sanitising and refactoring so the (re) locking isn't so heavy. Right now I'm going for correctness, not speed. * The BAR TX can fail if the hardware TX queue is full. Since there's no "free" space kept for management frames, a full TX queue (from eg an iperf test) can race with your ability to allocate ath_buf/mbufs and cause issues. I'll knock this on the head with a subsequent commit. * I need to do some _much_ more thorough testing in hostap mode to ensure that many concurrent traffic streams to different end nodes are correctly handled. I'll find and squish whichever bugs show up here. But, this is an important step to being able to flip on 802.11n by default. The last issue (besides bug fixes, of course) is HT frame protection and I'll address that in a subsequent commit.
2012-04-04 23:45:15 +00:00
/*
* Send BAR if required
*/
if (ath_tx_tid_bar_tx_ready(sc, atid))
ath_tx_tid_bar_tx(sc, atid);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_default_comp(sc, bf, fail);
/* bf is freed at this point */
}
void
ath_tx_aggr_comp(struct ath_softc *sc, struct ath_buf *bf, int fail)
{
if (bf->bf_state.bfs_aggr)
ath_tx_aggr_comp_aggr(sc, bf, fail);
else
ath_tx_aggr_comp_unaggr(sc, bf, fail);
}
/*
* Schedule some packets from the given node/TID to the hardware.
*
* This is the aggregate version.
*/
void
ath_tx_tid_hw_queue_aggr(struct ath_softc *sc, struct ath_node *an,
struct ath_tid *tid)
{
struct ath_buf *bf;
struct ath_txq *txq = sc->sc_ac2q[tid->ac];
struct ieee80211_tx_ampdu *tap;
ATH_AGGR_STATUS status;
ath_bufhead bf_q;
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: tid=%d\n", __func__, tid->tid);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* XXX TODO: If we're called for a queue that we're leaking frames to,
* ensure we only leak one.
*/
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
tap = ath_tx_get_tx_tid(an, tid->tid);
if (tid->tid == IEEE80211_NONQOS_TID)
DPRINTF(sc, ATH_DEBUG_SW_TX,
"%s: called for TID=NONQOS_TID?\n", __func__);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
for (;;) {
status = ATH_AGGR_DONE;
/*
* If the upper layer has paused the TID, don't
* queue any further packets.
*
* This can also occur from the completion task because
* of packet loss; but as its serialised with this code,
* it won't "appear" half way through queuing packets.
*/
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
if (! ath_tx_tid_can_tx_or_sched(sc, tid))
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
break;
bf = ATH_TID_FIRST(tid);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (bf == NULL) {
break;
}
/*
* If the packet doesn't fall within the BAW (eg a NULL
* data frame), schedule it directly; continue.
*/
if (! bf->bf_state.bfs_dobaw) {
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
"%s: non-baw packet\n",
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
__func__);
ATH_TID_REMOVE(tid, bf, bf_list);
if (bf->bf_state.bfs_nframes > 1)
DPRINTF(sc, ATH_DEBUG_SW_TX,
"%s: aggr=%d, nframes=%d\n",
__func__,
bf->bf_state.bfs_aggr,
bf->bf_state.bfs_nframes);
/*
* This shouldn't happen - such frames shouldn't
* ever have been queued as an aggregate in the
* first place. However, make sure the fields
* are correctly setup just to be totally sure.
*/
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
bf->bf_state.bfs_aggr = 0;
bf->bf_state.bfs_nframes = 1;
/* Update CLRDMASK just before this frame is queued */
ath_tx_update_clrdmask(sc, tid, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_do_ratelookup(sc, bf);
ath_tx_calc_duration(sc, bf);
ath_tx_calc_protection(sc, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_set_rtscts(sc, bf);
ath_tx_rate_fill_rcflags(sc, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_setds(sc, bf);
ath_hal_clr11n_aggr(sc->sc_ah, bf->bf_desc);
sc->sc_aggr_stats.aggr_nonbaw_pkt++;
/* Queue the packet; continue */
goto queuepkt;
}
TAILQ_INIT(&bf_q);
/*
* Do a rate control lookup on the first frame in the
* list. The rate control code needs that to occur
* before it can determine whether to TX.
* It's inaccurate because the rate control code doesn't
* really "do" aggregate lookups, so it only considers
* the size of the first frame.
*/
ath_tx_do_ratelookup(sc, bf);
bf->bf_state.bfs_rc[3].rix = 0;
bf->bf_state.bfs_rc[3].tries = 0;
ath_tx_calc_duration(sc, bf);
ath_tx_calc_protection(sc, bf);
ath_tx_set_rtscts(sc, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_rate_fill_rcflags(sc, bf);
status = ath_tx_form_aggr(sc, an, tid, &bf_q);
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
"%s: ath_tx_form_aggr() status=%d\n", __func__, status);
/*
* No frames to be picked up - out of BAW
*/
if (TAILQ_EMPTY(&bf_q))
break;
/*
* This assumes that the descriptor list in the ath_bufhead
* are already linked together via bf_next pointers.
*/
bf = TAILQ_FIRST(&bf_q);
if (status == ATH_AGGR_8K_LIMITED)
sc->sc_aggr_stats.aggr_rts_aggr_limited++;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* If it's the only frame send as non-aggregate
* assume that ath_tx_form_aggr() has checked
* whether it's in the BAW and added it appropriately.
*/
if (bf->bf_state.bfs_nframes == 1) {
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
"%s: single-frame aggregate\n", __func__);
/* Update CLRDMASK just before this frame is queued */
ath_tx_update_clrdmask(sc, tid, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
bf->bf_state.bfs_aggr = 0;
bf->bf_state.bfs_ndelim = 0;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_setds(sc, bf);
ath_hal_clr11n_aggr(sc->sc_ah, bf->bf_desc);
if (status == ATH_AGGR_BAW_CLOSED)
sc->sc_aggr_stats.aggr_baw_closed_single_pkt++;
else
sc->sc_aggr_stats.aggr_single_pkt++;
} else {
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
"%s: multi-frame aggregate: %d frames, "
"length %d\n",
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
__func__, bf->bf_state.bfs_nframes,
bf->bf_state.bfs_al);
bf->bf_state.bfs_aggr = 1;
sc->sc_aggr_stats.aggr_pkts[bf->bf_state.bfs_nframes]++;
sc->sc_aggr_stats.aggr_aggr_pkt++;
/* Update CLRDMASK just before this frame is queued */
ath_tx_update_clrdmask(sc, tid, bf);
/*
* Calculate the duration/protection as required.
*/
ath_tx_calc_duration(sc, bf);
ath_tx_calc_protection(sc, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Update the rate and rtscts information based on the
* rate decision made by the rate control code;
* the first frame in the aggregate needs it.
*/
ath_tx_set_rtscts(sc, bf);
/*
* Setup the relevant descriptor fields
* for aggregation. The first descriptor
* already points to the rest in the chain.
*/
ath_tx_setds_11n(sc, bf);
}
queuepkt:
/* Set completion handler, multi-frame aggregate or not */
bf->bf_comp = ath_tx_aggr_comp;
if (bf->bf_state.bfs_tid == IEEE80211_NONQOS_TID)
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: TID=16?\n", __func__);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* Update leak count and frame config if were leaking frames.
*
* XXX TODO: it should update all frames in an aggregate
* correctly!
*/
ath_tx_leak_count_update(sc, tid, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Punt to txq */
ath_tx_handoff(sc, txq, bf);
/* Track outstanding buffer count to hardware */
/* aggregates are "one" buffer */
tid->hwq_depth++;
/*
* Break out if ath_tx_form_aggr() indicated
* there can't be any further progress (eg BAW is full.)
* Checking for an empty txq is done above.
*
* XXX locking on txq here?
*/
/* XXX TXQ locking */
if (txq->axq_aggr_depth >= sc->sc_hwq_limit_aggr ||
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
(status == ATH_AGGR_BAW_CLOSED ||
status == ATH_AGGR_LEAK_CLOSED))
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
break;
}
}
/*
* Schedule some packets from the given node/TID to the hardware.
*
* XXX TODO: this routine doesn't enforce the maximum TXQ depth.
* It just dumps frames into the TXQ. We should limit how deep
* the transmit queue can grow for frames dispatched to the given
* TXQ.
*
* To avoid locking issues, either we need to own the TXQ lock
* at this point, or we need to pass in the maximum frame count
* from the caller.
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
*/
void
ath_tx_tid_hw_queue_norm(struct ath_softc *sc, struct ath_node *an,
struct ath_tid *tid)
{
struct ath_buf *bf;
struct ath_txq *txq = sc->sc_ac2q[tid->ac];
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: node %p: TID %d: called\n",
__func__, an, tid->tid);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Check - is AMPDU pending or running? then print out something */
if (ath_tx_ampdu_pending(sc, an, tid->tid))
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: tid=%d, ampdu pending?\n",
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
__func__, tid->tid);
if (ath_tx_ampdu_running(sc, an, tid->tid))
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: tid=%d, ampdu running?\n",
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
__func__, tid->tid);
for (;;) {
/*
* If the upper layers have paused the TID, don't
* queue any further packets.
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
*
* XXX if we are leaking frames, make sure we decrement
* that counter _and_ we continue here.
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
*/
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
if (! ath_tx_tid_can_tx_or_sched(sc, tid))
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
break;
bf = ATH_TID_FIRST(tid);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
if (bf == NULL) {
break;
}
ATH_TID_REMOVE(tid, bf, bf_list);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Sanity check! */
if (tid->tid != bf->bf_state.bfs_tid) {
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: bfs_tid %d !="
" tid %d\n", __func__, bf->bf_state.bfs_tid,
tid->tid);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
/* Normal completion handler */
bf->bf_comp = ath_tx_normal_comp;
/*
* Override this for now, until the non-aggregate
* completion handler correctly handles software retransmits.
*/
bf->bf_state.bfs_txflags |= HAL_TXDESC_CLRDMASK;
/* Update CLRDMASK just before this frame is queued */
ath_tx_update_clrdmask(sc, tid, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Program descriptors + rate control */
ath_tx_do_ratelookup(sc, bf);
ath_tx_calc_duration(sc, bf);
ath_tx_calc_protection(sc, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_set_rtscts(sc, bf);
ath_tx_rate_fill_rcflags(sc, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_setds(sc, bf);
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* Update the current leak count if
* we're leaking frames; and set the
* MORE flag as appropriate.
*/
ath_tx_leak_count_update(sc, tid, bf);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Track outstanding buffer count to hardware */
/* aggregates are "one" buffer */
tid->hwq_depth++;
/* Punt to hardware or software txq */
ath_tx_handoff(sc, txq, bf);
}
}
/*
* Schedule some packets to the given hardware queue.
*
* This function walks the list of TIDs (ie, ath_node TIDs
* with queued traffic) and attempts to schedule traffic
* from them.
*
* TID scheduling is implemented as a FIFO, with TIDs being
* added to the end of the queue after some frames have been
* scheduled.
*/
void
ath_txq_sched(struct ath_softc *sc, struct ath_txq *txq)
{
struct ath_tid *tid, *next, *last;
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK_ASSERT(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Don't schedule if the hardware queue is busy.
* This (hopefully) gives some more time to aggregate
* some packets in the aggregation queue.
*
* XXX It doesn't stop a parallel sender from sneaking
* in transmitting a frame!
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
*/
/* XXX TXQ locking */
if (txq->axq_aggr_depth + txq->fifo.axq_depth >= sc->sc_hwq_limit_aggr) {
sc->sc_aggr_stats.aggr_sched_nopkt++;
return;
}
if (txq->axq_depth >= sc->sc_hwq_limit_nonaggr) {
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
sc->sc_aggr_stats.aggr_sched_nopkt++;
return;
}
last = TAILQ_LAST(&txq->axq_tidq, axq_t_s);
TAILQ_FOREACH_SAFE(tid, &txq->axq_tidq, axq_qelem, next) {
/*
* Suspend paused queues here; they'll be resumed
* once the addba completes or times out.
*/
DPRINTF(sc, ATH_DEBUG_SW_TX, "%s: tid=%d, paused=%d\n",
__func__, tid->tid, tid->paused);
ath_tx_tid_unsched(sc, tid);
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* This node may be in power-save and we're leaking
* a frame; be careful.
*/
if (! ath_tx_tid_can_tx_or_sched(sc, tid)) {
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
continue;
}
if (ath_tx_ampdu_running(sc, tid->an, tid->tid))
ath_tx_tid_hw_queue_aggr(sc, tid->an, tid);
else
ath_tx_tid_hw_queue_norm(sc, tid->an, tid);
/* Not empty? Re-schedule */
if (tid->axq_depth != 0)
ath_tx_tid_sched(sc, tid);
/*
* Give the software queue time to aggregate more
* packets. If we aren't running aggregation then
* we should still limit the hardware queue depth.
*/
/* XXX TXQ locking */
if (txq->axq_aggr_depth + txq->fifo.axq_depth >= sc->sc_hwq_limit_aggr) {
break;
}
if (txq->axq_depth >= sc->sc_hwq_limit_nonaggr) {
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
break;
}
/*
* If this was the last entry on the original list, stop.
* Otherwise nodes that have been rescheduled onto the end
* of the TID FIFO list will just keep being rescheduled.
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
*
* XXX What should we do about nodes that were paused
* but are pending a leaking frame in response to a ps-poll?
* They'll be put at the front of the list; so they'll
* prematurely trigger this condition! Ew.
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
*/
if (tid == last)
break;
}
}
/*
* TX addba handling
*/
/*
* Return net80211 TID struct pointer, or NULL for none
*/
struct ieee80211_tx_ampdu *
ath_tx_get_tx_tid(struct ath_node *an, int tid)
{
struct ieee80211_node *ni = &an->an_node;
struct ieee80211_tx_ampdu *tap;
if (tid == IEEE80211_NONQOS_TID)
return NULL;
tap = &ni->ni_tx_ampdu[tid];
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
return tap;
}
/*
* Is AMPDU-TX running?
*/
static int
ath_tx_ampdu_running(struct ath_softc *sc, struct ath_node *an, int tid)
{
struct ieee80211_tx_ampdu *tap;
if (tid == IEEE80211_NONQOS_TID)
return 0;
tap = ath_tx_get_tx_tid(an, tid);
if (tap == NULL)
return 0; /* Not valid; default to not running */
return !! (tap->txa_flags & IEEE80211_AGGR_RUNNING);
}
/*
* Is AMPDU-TX negotiation pending?
*/
static int
ath_tx_ampdu_pending(struct ath_softc *sc, struct ath_node *an, int tid)
{
struct ieee80211_tx_ampdu *tap;
if (tid == IEEE80211_NONQOS_TID)
return 0;
tap = ath_tx_get_tx_tid(an, tid);
if (tap == NULL)
return 0; /* Not valid; default to not pending */
return !! (tap->txa_flags & IEEE80211_AGGR_XCHGPEND);
}
/*
* Is AMPDU-TX pending for the given TID?
*/
/*
* Method to handle sending an ADDBA request.
*
* We tap this so the relevant flags can be set to pause the TID
* whilst waiting for the response.
*
* XXX there's no timeout handler we can override?
*/
int
ath_addba_request(struct ieee80211_node *ni, struct ieee80211_tx_ampdu *tap,
int dialogtoken, int baparamset, int batimeout)
{
struct ath_softc *sc = ni->ni_ic->ic_ifp->if_softc;
int tid = tap->txa_tid;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
struct ath_node *an = ATH_NODE(ni);
struct ath_tid *atid = &an->an_tid[tid];
/*
* XXX danger Will Robinson!
*
* Although the taskqueue may be running and scheduling some more
* packets, these should all be _before_ the addba sequence number.
* However, net80211 will keep self-assigning sequence numbers
* until addba has been negotiated.
*
* In the past, these packets would be "paused" (which still works
* fine, as they're being scheduled to the driver in the same
* serialised method which is calling the addba request routine)
* and when the aggregation session begins, they'll be dequeued
* as aggregate packets and added to the BAW. However, now there's
* a "bf->bf_state.bfs_dobaw" flag, and this isn't set for these
* packets. Thus they never get included in the BAW tracking and
* this can cause the initial burst of packets after the addba
* negotiation to "hang", as they quickly fall outside the BAW.
*
* The "eventual" solution should be to tag these packets with
* dobaw. Although net80211 has given us a sequence number,
* it'll be "after" the left edge of the BAW and thus it'll
* fall within it.
*/
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
/*
* This is a bit annoying. Until net80211 HT code inherits some
* (any) locking, we may have this called in parallel BUT only
* one response/timeout will be called. Grr.
*/
if (atid->addba_tx_pending == 0) {
ath_tx_tid_pause(sc, atid);
atid->addba_tx_pending = 1;
}
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX_CTRL,
"%s: %6D: called; dialogtoken=%d, baparamset=%d, batimeout=%d\n",
__func__,
ni->ni_macaddr,
":",
dialogtoken, baparamset, batimeout);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX_CTRL,
"%s: txa_start=%d, ni_txseqs=%d\n",
__func__, tap->txa_start, ni->ni_txseqs[tid]);
return sc->sc_addba_request(ni, tap, dialogtoken, baparamset,
batimeout);
}
/*
* Handle an ADDBA response.
*
* We unpause the queue so TX'ing can resume.
*
* Any packets TX'ed from this point should be "aggregate" (whether
* aggregate or not) so the BAW is updated.
*
* Note! net80211 keeps self-assigning sequence numbers until
* ampdu is negotiated. This means the initially-negotiated BAW left
* edge won't match the ni->ni_txseq.
*
* So, being very dirty, the BAW left edge is "slid" here to match
* ni->ni_txseq.
*
* What likely SHOULD happen is that all packets subsequent to the
* addba request should be tagged as aggregate and queued as non-aggregate
* frames; thus updating the BAW. For now though, I'll just slide the
* window.
*/
int
ath_addba_response(struct ieee80211_node *ni, struct ieee80211_tx_ampdu *tap,
int status, int code, int batimeout)
{
struct ath_softc *sc = ni->ni_ic->ic_ifp->if_softc;
int tid = tap->txa_tid;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
struct ath_node *an = ATH_NODE(ni);
struct ath_tid *atid = &an->an_tid[tid];
int r;
DPRINTF(sc, ATH_DEBUG_SW_TX_CTRL,
"%s: %6D: called; status=%d, code=%d, batimeout=%d\n", __func__,
ni->ni_macaddr,
":",
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
status, code, batimeout);
DPRINTF(sc, ATH_DEBUG_SW_TX_CTRL,
"%s: txa_start=%d, ni_txseqs=%d\n",
__func__, tap->txa_start, ni->ni_txseqs[tid]);
/*
* Call this first, so the interface flags get updated
* before the TID is unpaused. Otherwise a race condition
* exists where the unpaused TID still doesn't yet have
* IEEE80211_AGGR_RUNNING set.
*/
r = sc->sc_addba_response(ni, tap, status, code, batimeout);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
atid->addba_tx_pending = 0;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* XXX dirty!
* Slide the BAW left edge to wherever net80211 left it for us.
* Read above for more information.
*/
tap->txa_start = ni->ni_txseqs[tid];
ath_tx_tid_resume(sc, atid);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
return r;
}
/*
* Stop ADDBA on a queue.
*
* This can be called whilst BAR TX is currently active on the queue,
* so make sure this is unblocked before continuing.
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
*/
void
ath_addba_stop(struct ieee80211_node *ni, struct ieee80211_tx_ampdu *tap)
{
struct ath_softc *sc = ni->ni_ic->ic_ifp->if_softc;
int tid = tap->txa_tid;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
struct ath_node *an = ATH_NODE(ni);
struct ath_tid *atid = &an->an_tid[tid];
ath_bufhead bf_cq;
struct ath_buf *bf;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
DPRINTF(sc, ATH_DEBUG_SW_TX_CTRL, "%s: %6D: called\n",
__func__,
ni->ni_macaddr,
":");
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/*
* Pause TID traffic early, so there aren't any races
* Unblock the pending BAR held traffic, if it's currently paused.
*/
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_tid_pause(sc, atid);
if (atid->bar_wait) {
/*
* bar_unsuspend() expects bar_tx == 1, as it should be
* called from the TX completion path. This quietens
* the warning. It's cleared for us anyway.
*/
atid->bar_tx = 1;
ath_tx_tid_bar_unsuspend(sc, atid);
}
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* There's no need to hold the TXQ lock here */
sc->sc_addba_stop(ni, tap);
/*
* ath_tx_tid_cleanup will resume the TID if possible, otherwise
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
* it'll set the cleanup flag, and it'll be unpaused once
* things have been cleaned up.
*/
TAILQ_INIT(&bf_cq);
ATH_TX_LOCK(sc);
ath_tx_tid_cleanup(sc, an, tid, &bf_cq);
/*
* Unpause the TID if no cleanup is required.
*/
if (! atid->cleanup_inprogress)
ath_tx_tid_resume(sc, atid);
ATH_TX_UNLOCK(sc);
/* Handle completing frames and fail them */
while ((bf = TAILQ_FIRST(&bf_cq)) != NULL) {
TAILQ_REMOVE(&bf_cq, bf, bf_list);
ath_tx_default_comp(sc, bf, 1);
}
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
}
/*
* Handle a node reassociation.
*
* We may have a bunch of frames queued to the hardware; those need
* to be marked as cleanup.
*/
void
ath_tx_node_reassoc(struct ath_softc *sc, struct ath_node *an)
{
struct ath_tid *tid;
int i;
ath_bufhead bf_cq;
struct ath_buf *bf;
TAILQ_INIT(&bf_cq);
ATH_TX_UNLOCK_ASSERT(sc);
ATH_TX_LOCK(sc);
for (i = 0; i < IEEE80211_TID_SIZE; i++) {
tid = &an->an_tid[i];
if (tid->hwq_depth == 0)
continue;
ath_tx_tid_pause(sc, tid);
DPRINTF(sc, ATH_DEBUG_NODE,
"%s: %6D: TID %d: cleaning up TID\n",
__func__,
an->an_node.ni_macaddr,
":",
i);
ath_tx_tid_cleanup(sc, an, i, &bf_cq);
/*
* Unpause the TID if no cleanup is required.
*/
if (! tid->cleanup_inprogress)
ath_tx_tid_resume(sc, tid);
}
ATH_TX_UNLOCK(sc);
/* Handle completing frames and fail them */
while ((bf = TAILQ_FIRST(&bf_cq)) != NULL) {
TAILQ_REMOVE(&bf_cq, bf, bf_list);
ath_tx_default_comp(sc, bf, 1);
}
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
/*
* Note: net80211 bar_timeout() doesn't call this function on BAR failure;
* it simply tears down the aggregation session. Ew.
*
* It however will call ieee80211_ampdu_stop() which will call
* ic->ic_addba_stop().
*
* XXX This uses a hard-coded max BAR count value; the whole
* XXX BAR TX success or failure should be better handled!
*/
void
ath_bar_response(struct ieee80211_node *ni, struct ieee80211_tx_ampdu *tap,
int status)
{
struct ath_softc *sc = ni->ni_ic->ic_ifp->if_softc;
int tid = tap->txa_tid;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
struct ath_node *an = ATH_NODE(ni);
struct ath_tid *atid = &an->an_tid[tid];
int attempts = tap->txa_attempts;
DPRINTF(sc, ATH_DEBUG_SW_TX_BAR,
"%s: %6D: called; txa_tid=%d, atid->tid=%d, status=%d, attempts=%d\n",
__func__,
ni->ni_macaddr,
":",
tap->txa_tid,
atid->tid,
status,
attempts);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Note: This may update the BAW details */
sc->sc_bar_response(ni, tap, status);
/* Unpause the TID */
/*
* XXX if this is attempt=50, the TID will be downgraded
* XXX to a non-aggregate session. So we must unpause the
* XXX TID here or it'll never be done.
*
* Also, don't call it if bar_tx/bar_wait are 0; something
* has beaten us to the punch? (XXX figure out what?)
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
*/
if (status == 0 || attempts == 50) {
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
if (atid->bar_tx == 0 || atid->bar_wait == 0)
DPRINTF(sc, ATH_DEBUG_SW_TX_BAR,
"%s: huh? bar_tx=%d, bar_wait=%d\n",
__func__,
atid->bar_tx, atid->bar_wait);
else
ath_tx_tid_bar_unsuspend(sc, atid);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
}
/*
* This is called whenever the pending ADDBA request times out.
* Unpause and reschedule the TID.
*/
void
ath_addba_response_timeout(struct ieee80211_node *ni,
struct ieee80211_tx_ampdu *tap)
{
struct ath_softc *sc = ni->ni_ic->ic_ifp->if_softc;
int tid = tap->txa_tid;
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
struct ath_node *an = ATH_NODE(ni);
struct ath_tid *atid = &an->an_tid[tid];
DPRINTF(sc, ATH_DEBUG_SW_TX_CTRL,
"%s: %6D: TID=%d, called; resuming\n",
__func__,
ni->ni_macaddr,
":",
tid);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
atid->addba_tx_pending = 0;
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
/* Note: This updates the aggregate state to (again) pending */
sc->sc_addba_response_timeout(ni, tap);
/* Unpause the TID; which reschedules it */
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
ath_tx_tid_resume(sc, atid);
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
Introduce TX aggregation and software TX queue management for Atheros AR5416 and later wireless devices. This is a very large commit - the complete history can be found in the user/adrian/if_ath_tx branch. Legacy (ie, pre-AR5416) devices also use the per-software TXQ support and (in theory) can support non-aggregation ADDBA sessions. However, the net80211 stack doesn't currently support this. In summary: TX path: * queued frames normally go onto a per-TID, per-node queue * some special frames (eg ADDBA control frames) are thrown directly onto the relevant hardware queue so they can go out before any software queued frames are queued. * Add methods to create, suspend, resume and tear down an aggregation session. * Add in software retransmission of both normal and aggregate frames. * Add in completion handling of aggregate frames, including parsing the block ack bitmap provided by the hardware. * Write an aggregation function which can assemble frames into an aggregate based on the selected rate control and channel configuration. * The per-TID queues are locked based on their target hardware TX queue. This matches what ath9k/atheros does, and thus simplified porting over some of the aggregation logic. * When doing TX aggregation, stick the sequence number allocation in the TX path rather than net80211 TX path, and protect it by the TXQ lock. Rate control: * Delay rate control selection until the frame is about to be queued to the hardware, so retried frames can have their rate control choices changed. Frames with a static rate control selection have that applied before each TX, just to simplify the TX path (ie, not have "static" and "dynamic" rate control special cased.) * Teach ath_rate_sample about aggregates - both completion and errors. * Add an EWMA for tracking what the current "good" MCS rate is based on failure rates. Misc: * Introduce a bunch of dirty hacks and workarounds so TID mapping and net80211 frame inspection can be kept out of the net80211 layer. Because of the way this code works (and it's from Atheros and Linux ath9k), there is a consistent, 1:1 mapping between TID and AC. So we need to ensure that frames going to a specific TID will _always_ end up on the right AC, and vice versa, or the completion/locking will simply get very confused. I plan on addressing this mess in the future. Known issues: * There is no BAR frame transmission just yet. A whole lot of tidying up needs to occur before BAR frame TX can occur in the "correct" place - ie, once the TID TX queue has been drained. * Interface reset/purge/etc results in frames in the TX and RX queues being removed. This creates holes in the sequence numbers being assigned and the TX/RX AMPDU code (on either side) just hangs. * There's no filtered frame support at the present moment, so stations going into power saving mode will simply have a number of frames dropped - likely resulting in a traffic "hang". * Raw frame TX is going to just not function with 11n aggregation. Likely this needs to be modified to always override the sequence number if the frame is going into an aggregation session. However, general raw frame injection currently doesn't work in general in net80211, so let's just ignore this for now until this is sorted out. * HT protection is just not implemented and won't be until the above is sorted out. In addition, the AR5416 has issues RTS protecting large aggregates (anything >8k), so the work around needs to be ported and tested. Thus, this will be put on hold until the above work is complete. * The rate control module 'sample' is the only currently supported module; onoe/amrr haven't been tested and have likely bit rotted a little. I'll follow up with some commits to make them work again for non-11n rates, but they won't be updated to handle 11n and aggregation. If someone wishes to do so then they're welcome to send along patches. * .. and "sample" doesn't really do a good job of 11n TX. Specifically, the metrics used (packet TX time and failure/success rates) isn't as useful for 11n. It's likely that it should be extended to take into account the aggregate throughput possible and then choose a rate which maximises that. Ie, it may be acceptable for a higher MCS rate with a higher failure to be used if it gives a more acceptable throughput/latency then a lower MCS rate @ a lower error rate. Again, patches will be gratefully accepted. Because of this, ATH_ENABLE_11N is still not enabled by default. Sponsored by: Hobnob, Inc. Obtained from: Linux, Atheros
2011-11-08 22:43:13 +00:00
}
/*
* Check if a node is asleep or not.
*/
int
ath_tx_node_is_asleep(struct ath_softc *sc, struct ath_node *an)
{
ATH_TX_LOCK_ASSERT(sc);
return (an->an_is_powersave);
}
/*
* Mark a node as currently "in powersaving."
* This suspends all traffic on the node.
*
* This must be called with the node/tx locks free.
*
* XXX TODO: the locking silliness below is due to how the node
* locking currently works. Right now, the node lock is grabbed
* to do rate control lookups and these are done with the TX
* queue lock held. This means the node lock can't be grabbed
* first here or a LOR will occur.
*
* Eventually (hopefully!) the TX path code will only grab
* the TXQ lock when transmitting and the ath_node lock when
* doing node/TID operations. There are other complications -
* the sched/unsched operations involve walking the per-txq
* 'active tid' list and this requires both locks to be held.
*/
void
ath_tx_node_sleep(struct ath_softc *sc, struct ath_node *an)
{
struct ath_tid *atid;
struct ath_txq *txq;
int tid;
ATH_TX_UNLOCK_ASSERT(sc);
/* Suspend all traffic on the node */
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_LOCK(sc);
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
if (an->an_is_powersave) {
DPRINTF(sc, ATH_DEBUG_XMIT,
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
"%s: %6D: node was already asleep!\n",
__func__, an->an_node.ni_macaddr, ":");
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
ATH_TX_UNLOCK(sc);
return;
}
for (tid = 0; tid < IEEE80211_TID_SIZE; tid++) {
atid = &an->an_tid[tid];
txq = sc->sc_ac2q[atid->ac];
ath_tx_tid_pause(sc, atid);
}
/* Mark node as in powersaving */
an->an_is_powersave = 1;
ATH_TX_UNLOCK(sc);
}
/*
* Mark a node as currently "awake."
* This resumes all traffic to the node.
*/
void
ath_tx_node_wakeup(struct ath_softc *sc, struct ath_node *an)
{
struct ath_tid *atid;
struct ath_txq *txq;
int tid;
ATH_TX_UNLOCK_ASSERT(sc);
ATH_TX_LOCK(sc);
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/* !? */
if (an->an_is_powersave == 0) {
ATH_TX_UNLOCK(sc);
DPRINTF(sc, ATH_DEBUG_XMIT,
"%s: an=%p: node was already awake\n",
__func__, an);
return;
}
/* Mark node as awake */
an->an_is_powersave = 0;
Implement my first cut at "correct" node power-save and PS-POLL support. This implements PS-POLL awareness i nthe * Implement frame "leaking", which allows for a software queue to be scheduled even though it's asleep * Track whether a frame has been leaked or not * Leak out a single non-AMPDU frame when transmitting aggregates * Queue BAR frames if the node is asleep * Direct-dispatch the rest of control and management frames. This allows for things like re-association to occur (which involves sending probe req/resp as well as assoc request/response) when the node is asleep and then tries reassociating. * Limit how many frames can set in the software node queue whilst the node is asleep. net80211 is already buffering frames for us so this is mostly just paranoia. * Add a PS-POLL method which leaks out a frame if there's something in the software queue, else it calls net80211's ps-poll routine. Since the ath PS-POLL routine marks the node as having a single frame to leak, either a software queued frame would leak, OR the next queued frame would leak. The next queued frame could be something from the net80211 power save queue, OR it could be a NULL frame from net80211. TODO: * Don't transmit further BAR frames (eg via a timeout) if the node is currently asleep. Otherwise we may end up exhausting management frames due to the lots of queued BAR frames. I may just undo this bit later on and direct-dispatch BAR frames even if the node is asleep. * It would be nice to burst out a single A-MPDU frame if both ends support this. I may end adding a FreeBSD IE soon to negotiate this power save behaviour. * I should make STAs timeout of power save mode if they've been in power save for more than a handful of seconds. This way cards that get "stuck" in power save mode don't stay there for the "inactivity" timeout in net80211. * Move the queue depth check into the driver layer (ath_start / ath_transmit) rather than doing it in the TX path. * There could be some naughty corner cases with ps-poll leaking. Specifically, if net80211 generates a NULL data frame whilst another transmitter sends a normal data frame out net80211 output / transmit, we need to ensure that the NULL data frame goes out first. This is one of those things that should occur inside the VAP/ic TX lock. Grr, more investigations to do.. Tested: * STA: AR5416, AR9280 * AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
/*
* Clear any pending leaked frame requests
*/
an->an_leak_count = 0;
for (tid = 0; tid < IEEE80211_TID_SIZE; tid++) {
atid = &an->an_tid[tid];
txq = sc->sc_ac2q[atid->ac];
ath_tx_tid_resume(sc, atid);
}
Delete the per-TXQ locks and replace them with a single TX lock. I couldn't think of a way to maintain the hardware TXQ locks _and_ layer on top of that per-TXQ software queuing and any other kind of fine-grained locks (eg per-TID, or per-node locks.) So for now, to facilitate some further code refactoring and development as part of the final push to get software queue ps-poll and u-apsd handling into this driver, just do away with them entirely. I may eventually bring them back at some point, when it looks slightly more architectually cleaner to do so. But as it stands at the present, it's not really buying us much: * in order to properly serialise things and not get bitten by scheduling and locking interactions with things higher up in the stack, we need to wrap the whole TX path in a long held lock. Otherwise we can end up being pre-empted during frame handling, resulting in some out of order frame handling between sequence number allocation and encryption handling (ie, the seqno and the CCMP IV get out of sequence); * .. so whilst that's the case, holding the lock for that long means that we're acquiring and releasing the TXQ lock _inside_ that context; * And we also acquire it per-frame during frame completion, but we currently can't hold the lock for the duration of the TX completion as we need to call net80211 layer things with the locks _unheld_ to avoid LOR. * .. the other places were grab that lock are reset/flush, which don't happen often. My eventual aim is to change the TX path so all rejected frame transmissions and all frame completions result in any ieee80211_free_node() calls to occur outside of the TX lock; then I can cut back on the amount of locking that goes on here. There may be some LORs that occur when ieee80211_free_node() is called when the TX queue path fails; I'll begin to address these in follow-up commits.
2012-12-02 06:24:08 +00:00
ATH_TX_UNLOCK(sc);
}
static int
ath_legacy_dma_txsetup(struct ath_softc *sc)
{
/* nothing new needed */
return (0);
}
static int
ath_legacy_dma_txteardown(struct ath_softc *sc)
{
/* nothing new needed */
return (0);
}
void
ath_xmit_setup_legacy(struct ath_softc *sc)
{
/*
* For now, just set the descriptor length to sizeof(ath_desc);
* worry about extracting the real length out of the HAL later.
*/
sc->sc_tx_desclen = sizeof(struct ath_desc);
sc->sc_tx_statuslen = sizeof(struct ath_desc);
sc->sc_tx_nmaps = 1; /* only one buffer per TX desc */
sc->sc_tx.xmit_setup = ath_legacy_dma_txsetup;
sc->sc_tx.xmit_teardown = ath_legacy_dma_txteardown;
sc->sc_tx.xmit_attach_comp_func = ath_legacy_attach_comp_func;
sc->sc_tx.xmit_dma_restart = ath_legacy_tx_dma_restart;
sc->sc_tx.xmit_handoff = ath_legacy_xmit_handoff;
sc->sc_tx.xmit_drain = ath_legacy_tx_drain;
}