freebsd-dev/sys/dev/ath/if_ath_misc.h
Adrian Chadd 1b5c5f5ad0 I give up - introduce a TX lock to serialise TX operations.
I've tried serialising TX using queues and such but unfortunately
due to how this interacts with the locking going on elsewhere in the
networking stack, the TX task gets delayed, resulting in quite a
noticable throughput loss:

* baseline TCP for 2x2 11n HT40 is ~ 170mbit/sec;
* TCP for TX task in the ath taskq, with the RX also going on - 80mbit/sec;
* TCP for TX task in a separate, second taskq - 100mbit/sec.

So for now I'm going with the Linux wireless stack approach - lock tx
early.  The linux code does in the wireless stack, before the 802.11
state stuff happens and before it's punted to the driver.
But TX locking needs to also occur at the driver layer as the TX
completion code _also_ begins to drain the ifnet TX queue.

Whilst I'm here, add some KTR traces for the TX path.

Note:

* This really should be done at the net80211 layer (as well, at least.)
  But that'll have to wait for a little more thought to happen.
2012-10-31 06:27:58 +00:00

133 lines
4.9 KiB
C

/*-
* Copyright (c) 2002-2009 Sam Leffler, Errno Consulting
* 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.
*
* $FreeBSD$
*/
#ifndef __IF_ATH_MISC_H__
#define __IF_ATH_MISC_H__
/*
* This is where definitions for "public things" in if_ath.c
* will go for the time being.
*
* Anything in here should eventually be moved out of if_ath.c
* and into something else.
*/
/* unaligned little endian access */
#define LE_READ_2(p) \
((u_int16_t) \
((((u_int8_t *)(p))[0] ) | (((u_int8_t *)(p))[1] << 8)))
#define LE_READ_4(p) \
((u_int32_t) \
((((u_int8_t *)(p))[0] ) | (((u_int8_t *)(p))[1] << 8) | \
(((u_int8_t *)(p))[2] << 16) | (((u_int8_t *)(p))[3] << 24)))
extern int ath_rxbuf;
extern int ath_txbuf;
extern int ath_txbuf_mgmt;
extern int ath_tx_findrix(const struct ath_softc *sc, uint8_t rate);
extern struct ath_buf * ath_getbuf(struct ath_softc *sc,
ath_buf_type_t btype);
extern struct ath_buf * _ath_getbuf_locked(struct ath_softc *sc,
ath_buf_type_t btype);
extern struct ath_buf * ath_buf_clone(struct ath_softc *sc,
const struct ath_buf *bf);
/* XXX change this to NULL the buffer pointer? */
extern void ath_freebuf(struct ath_softc *sc, struct ath_buf *bf);
extern void ath_returnbuf_head(struct ath_softc *sc, struct ath_buf *bf);
extern void ath_returnbuf_tail(struct ath_softc *sc, struct ath_buf *bf);
extern int ath_reset(struct ifnet *, ATH_RESET_TYPE);
extern void ath_tx_default_comp(struct ath_softc *sc, struct ath_buf *bf,
int fail);
extern void ath_tx_update_ratectrl(struct ath_softc *sc,
struct ieee80211_node *ni, struct ath_rc_series *rc,
struct ath_tx_status *ts, int frmlen, int nframes, int nbad);
extern void ath_tx_freebuf(struct ath_softc *sc, struct ath_buf *bf,
int status);
extern void ath_txqmove(struct ath_txq *dst, struct ath_txq *src);
extern void ath_mode_init(struct ath_softc *sc);
extern void ath_setdefantenna(struct ath_softc *sc, u_int antenna);
extern void ath_setslottime(struct ath_softc *sc);
extern int ath_descdma_alloc_desc(struct ath_softc *sc,
struct ath_descdma *dd, ath_bufhead *head, const char *name,
int ds_size, int ndesc);
extern int ath_descdma_setup(struct ath_softc *sc, struct ath_descdma *dd,
ath_bufhead *head, const char *name, int ds_size, int nbuf,
int ndesc);
extern int ath_descdma_setup_rx_edma(struct ath_softc *sc,
struct ath_descdma *dd, ath_bufhead *head, const char *name,
int nbuf, int desclen);
extern void ath_descdma_cleanup(struct ath_softc *sc,
struct ath_descdma *dd, ath_bufhead *head);
extern void ath_legacy_attach_comp_func(struct ath_softc *sc);
extern void ath_tx_draintxq(struct ath_softc *sc, struct ath_txq *txq);
extern void ath_legacy_tx_drain(struct ath_softc *sc,
ATH_RESET_TYPE reset_type);
extern void ath_tx_process_buf_completion(struct ath_softc *sc,
struct ath_txq *txq, struct ath_tx_status *ts, struct ath_buf *bf);
extern int ath_stoptxdma(struct ath_softc *sc);
extern void ath_tx_update_tim(struct ath_softc *sc,
struct ieee80211_node *ni, int enable);
/*
* This is only here so that the RX proc function can call it.
* It's very likely that the "start TX after RX" call should be
* done via something in if_ath.c, moving "rx tasklet" into
* if_ath.c and do the ath_start() call there. Once that's done,
* we can kill this.
*/
extern void ath_start(struct ifnet *ifp);
extern void ath_start_task(void *arg, int npending);
static inline void
ath_tx_kick(struct ath_softc *sc)
{
ATH_TX_LOCK(sc);
ath_start(sc->sc_ifp);
ATH_TX_UNLOCK(sc);
}
#endif