freebsd-skq/sys/dev/netmap/if_lem_netmap.h
Luigi Rizzo 847bf38369 Sync netmap sources with the version in our private tree.
This commit contains large contributions from Giuseppe Lettieri and
Stefano Garzarella, is partly supported by grants from Verisign and Cisco,
and brings in the following:

- fix zerocopy monitor ports and introduce copying monitor ports
  (the latter are lower performance but give access to all traffic
  in parallel with the application)

- exclusive open mode, useful to implement solutions that recover
  from crashes of the main netmap client (suggested by Patrick Kelsey)

- revised memory allocator in preparation for the 'passthrough mode'
  (ptnetmap) recently presented at bsdcan. ptnetmap is described in
        S. Garzarella, G. Lettieri, L. Rizzo;
        Virtual device passthrough for high speed VM networking,
        ACM/IEEE ANCS 2015, Oakland (CA) May 2015
        http://info.iet.unipi.it/~luigi/research.html

- fix rx CRC handing on ixl

- add module dependencies for netmap when building drivers as modules

- minor simplifications to device-specific routines (*txsync, *rxsync)

- general code cleanup (remove unused variables, introduce macros
  to access rings and remove duplicate code,

Applications do not need to be recompiled, unless of course
they want to use the new features (monitors and exclusive open).

Those willing to try this code on stable/10 can just update the
sys/dev/netmap/*, sys/net/netmap* with the version in HEAD
and apply the small patches to individual device drivers.

MFC after:	1 month
Sponsored by:	(partly) Verisign, Cisco
2015-07-10 05:51:36 +00:00

493 lines
14 KiB
C

/*
* Copyright (C) 2011-2014 Matteo Landi, Luigi Rizzo. 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.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, 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 DAMAGE.
*/
/*
* $FreeBSD$
*
* netmap support for: lem
*
* For details on netmap support please see ixgbe_netmap.h
*/
#include <net/netmap.h>
#include <sys/selinfo.h>
#include <vm/vm.h>
#include <vm/pmap.h> /* vtophys ? */
#include <dev/netmap/netmap_kern.h>
extern int netmap_adaptive_io;
/*
* Register/unregister. We are already under netmap lock.
*/
static int
lem_netmap_reg(struct netmap_adapter *na, int onoff)
{
struct ifnet *ifp = na->ifp;
struct adapter *adapter = ifp->if_softc;
EM_CORE_LOCK(adapter);
lem_disable_intr(adapter);
/* Tell the stack that the interface is no longer active */
ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
#ifndef EM_LEGACY_IRQ // XXX do we need this ?
taskqueue_block(adapter->tq);
taskqueue_drain(adapter->tq, &adapter->rxtx_task);
taskqueue_drain(adapter->tq, &adapter->link_task);
#endif /* !EM_LEGCY_IRQ */
/* enable or disable flags and callbacks in na and ifp */
if (onoff) {
nm_set_native_flags(na);
} else {
nm_clear_native_flags(na);
}
lem_init_locked(adapter); /* also enable intr */
#ifndef EM_LEGACY_IRQ
taskqueue_unblock(adapter->tq); // XXX do we need this ?
#endif /* !EM_LEGCY_IRQ */
EM_CORE_UNLOCK(adapter);
return (ifp->if_drv_flags & IFF_DRV_RUNNING ? 0 : 1);
}
/*
* Reconcile kernel and user view of the transmit ring.
*/
static int
lem_netmap_txsync(struct netmap_kring *kring, int flags)
{
struct netmap_adapter *na = kring->na;
struct ifnet *ifp = na->ifp;
struct netmap_ring *ring = kring->ring;
u_int nm_i; /* index into the netmap ring */
u_int nic_i; /* index into the NIC ring */
u_int const lim = kring->nkr_num_slots - 1;
u_int const head = kring->rhead;
/* generate an interrupt approximately every half ring */
u_int report_frequency = kring->nkr_num_slots >> 1;
/* device-specific */
struct adapter *adapter = ifp->if_softc;
#ifdef NIC_PARAVIRT
struct paravirt_csb *csb = adapter->csb;
uint64_t *csbd = (uint64_t *)(csb + 1);
#endif /* NIC_PARAVIRT */
bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
BUS_DMASYNC_POSTREAD);
/*
* First part: process new packets to send.
*/
nm_i = kring->nr_hwcur;
if (nm_i != head) { /* we have new packets to send */
#ifdef NIC_PARAVIRT
int do_kick = 0;
uint64_t t = 0; // timestamp
int n = head - nm_i;
if (n < 0)
n += lim + 1;
if (csb) {
t = rdtsc(); /* last timestamp */
csbd[16] += t - csbd[0]; /* total Wg */
csbd[17] += n; /* Wg count */
csbd[0] = t;
}
#endif /* NIC_PARAVIRT */
nic_i = netmap_idx_k2n(kring, nm_i);
while (nm_i != head) {
struct netmap_slot *slot = &ring->slot[nm_i];
u_int len = slot->len;
uint64_t paddr;
void *addr = PNMB(na, slot, &paddr);
/* device-specific */
struct e1000_tx_desc *curr = &adapter->tx_desc_base[nic_i];
struct em_buffer *txbuf = &adapter->tx_buffer_area[nic_i];
int flags = (slot->flags & NS_REPORT ||
nic_i == 0 || nic_i == report_frequency) ?
E1000_TXD_CMD_RS : 0;
NM_CHECK_ADDR_LEN(na, addr, len);
if (slot->flags & NS_BUF_CHANGED) {
/* buffer has changed, reload map */
curr->buffer_addr = htole64(paddr);
netmap_reload_map(na, adapter->txtag, txbuf->map, addr);
}
slot->flags &= ~(NS_REPORT | NS_BUF_CHANGED);
/* Fill the slot in the NIC ring. */
curr->upper.data = 0;
curr->lower.data = htole32(adapter->txd_cmd | len |
(E1000_TXD_CMD_EOP | flags) );
bus_dmamap_sync(adapter->txtag, txbuf->map,
BUS_DMASYNC_PREWRITE);
nm_i = nm_next(nm_i, lim);
nic_i = nm_next(nic_i, lim);
// XXX might try an early kick
}
kring->nr_hwcur = head;
/* synchronize the NIC ring */
bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
#ifdef NIC_PARAVIRT
/* set unconditionally, then also kick if needed */
if (csb) {
t = rdtsc();
if (csb->host_need_txkick == 2) {
/* can compute an update of delta */
int64_t delta = t - csbd[3];
if (delta < 0)
delta = -delta;
if (csbd[8] == 0 || delta < csbd[8]) {
csbd[8] = delta;
csbd[9]++;
}
csbd[10]++;
}
csb->guest_tdt = nic_i;
csbd[18] += t - csbd[0]; // total wp
csbd[19] += n;
}
if (!csb || !csb->guest_csb_on || (csb->host_need_txkick & 1))
do_kick = 1;
if (do_kick)
#endif /* NIC_PARAVIRT */
/* (re)start the tx unit up to slot nic_i (excluded) */
E1000_WRITE_REG(&adapter->hw, E1000_TDT(0), nic_i);
#ifdef NIC_PARAVIRT
if (do_kick) {
uint64_t t1 = rdtsc();
csbd[20] += t1 - t; // total Np
csbd[21]++;
}
#endif /* NIC_PARAVIRT */
}
/*
* Second part: reclaim buffers for completed transmissions.
*/
if (ticks != kring->last_reclaim || flags & NAF_FORCE_RECLAIM || nm_kr_txempty(kring)) {
kring->last_reclaim = ticks;
/* record completed transmissions using TDH */
#ifdef NIC_PARAVIRT
/* host updates tdh unconditionally, and we have
* no side effects on reads, so we can read from there
* instead of exiting.
*/
if (csb) {
static int drain = 0, nodrain=0, good = 0, bad = 0, fail = 0;
u_int x = adapter->next_tx_to_clean;
csbd[19]++; // XXX count reclaims
nic_i = csb->host_tdh;
if (csb->guest_csb_on) {
if (nic_i == x) {
bad++;
csbd[24]++; // failed reclaims
/* no progress, request kick and retry */
csb->guest_need_txkick = 1;
mb(); // XXX barrier
nic_i = csb->host_tdh;
} else {
good++;
}
if (nic_i != x) {
csb->guest_need_txkick = 2;
if (nic_i == csb->guest_tdt)
drain++;
else
nodrain++;
#if 1
if (netmap_adaptive_io) {
/* new mechanism: last half ring (or so)
* released one slot at a time.
* This effectively makes the system spin.
*
* Take next_to_clean + 1 as a reference.
* tdh must be ahead or equal
* On entry, the logical order is
* x < tdh = nic_i
* We first push tdh up to avoid wraps.
* The limit is tdh-ll (half ring).
* if tdh-256 < x we report x;
* else we report tdh-256
*/
u_int tdh = nic_i;
u_int ll = csbd[15];
u_int delta = lim/8;
if (netmap_adaptive_io == 2 || ll > delta)
csbd[15] = ll = delta;
else if (netmap_adaptive_io == 1 && ll > 1) {
csbd[15]--;
}
if (nic_i >= kring->nkr_num_slots) {
RD(5, "bad nic_i %d on input", nic_i);
}
x = nm_next(x, lim);
if (tdh < x)
tdh += lim + 1;
if (tdh <= x + ll) {
nic_i = x;
csbd[25]++; //report n + 1;
} else {
tdh = nic_i;
if (tdh < ll)
tdh += lim + 1;
nic_i = tdh - ll;
csbd[26]++; // report tdh - ll
}
}
#endif
} else {
/* we stop, count whether we are idle or not */
int bh_active = csb->host_need_txkick & 2 ? 4 : 0;
csbd[27+ csb->host_need_txkick]++;
if (netmap_adaptive_io == 1) {
if (bh_active && csbd[15] > 1)
csbd[15]--;
else if (!bh_active && csbd[15] < lim/2)
csbd[15]++;
}
bad--;
fail++;
}
}
RD(1, "drain %d nodrain %d good %d retry %d fail %d",
drain, nodrain, good, bad, fail);
} else
#endif /* !NIC_PARAVIRT */
nic_i = E1000_READ_REG(&adapter->hw, E1000_TDH(0));
if (nic_i >= kring->nkr_num_slots) { /* XXX can it happen ? */
D("TDH wrap %d", nic_i);
nic_i -= kring->nkr_num_slots;
}
adapter->next_tx_to_clean = nic_i;
kring->nr_hwtail = nm_prev(netmap_idx_n2k(kring, nic_i), lim);
}
return 0;
}
/*
* Reconcile kernel and user view of the receive ring.
*/
static int
lem_netmap_rxsync(struct netmap_kring *kring, int flags)
{
struct netmap_adapter *na = kring->na;
struct ifnet *ifp = na->ifp;
struct netmap_ring *ring = kring->ring;
u_int nm_i; /* index into the netmap ring */
u_int nic_i; /* index into the NIC ring */
u_int n;
u_int const lim = kring->nkr_num_slots - 1;
u_int const head = kring->rhead;
int force_update = (flags & NAF_FORCE_READ) || kring->nr_kflags & NKR_PENDINTR;
/* device-specific */
struct adapter *adapter = ifp->if_softc;
#ifdef NIC_PARAVIRT
struct paravirt_csb *csb = adapter->csb;
uint32_t csb_mode = csb && csb->guest_csb_on;
uint32_t do_host_rxkick = 0;
#endif /* NIC_PARAVIRT */
if (head > lim)
return netmap_ring_reinit(kring);
#ifdef NIC_PARAVIRT
if (csb_mode) {
force_update = 1;
csb->guest_need_rxkick = 0;
}
#endif /* NIC_PARAVIRT */
/* XXX check sync modes */
bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
/*
* First part: import newly received packets.
*/
if (netmap_no_pendintr || force_update) {
uint16_t slot_flags = kring->nkr_slot_flags;
nic_i = adapter->next_rx_desc_to_check;
nm_i = netmap_idx_n2k(kring, nic_i);
for (n = 0; ; n++) {
struct e1000_rx_desc *curr = &adapter->rx_desc_base[nic_i];
uint32_t staterr = le32toh(curr->status);
int len;
#ifdef NIC_PARAVIRT
if (csb_mode) {
if ((staterr & E1000_RXD_STAT_DD) == 0) {
/* don't bother to retry if more than 1 pkt */
if (n > 1)
break;
csb->guest_need_rxkick = 1;
wmb();
staterr = le32toh(curr->status);
if ((staterr & E1000_RXD_STAT_DD) == 0) {
break;
} else { /* we are good */
csb->guest_need_rxkick = 0;
}
}
} else
#endif /* NIC_PARAVIRT */
if ((staterr & E1000_RXD_STAT_DD) == 0)
break;
len = le16toh(curr->length) - 4; // CRC
if (len < 0) {
RD(5, "bogus pkt (%d) size %d nic idx %d", n, len, nic_i);
len = 0;
}
ring->slot[nm_i].len = len;
ring->slot[nm_i].flags = slot_flags;
bus_dmamap_sync(adapter->rxtag,
adapter->rx_buffer_area[nic_i].map,
BUS_DMASYNC_POSTREAD);
nm_i = nm_next(nm_i, lim);
nic_i = nm_next(nic_i, lim);
}
if (n) { /* update the state variables */
#ifdef NIC_PARAVIRT
if (csb_mode) {
if (n > 1) {
/* leave one spare buffer so we avoid rxkicks */
nm_i = nm_prev(nm_i, lim);
nic_i = nm_prev(nic_i, lim);
n--;
} else {
csb->guest_need_rxkick = 1;
}
}
#endif /* NIC_PARAVIRT */
ND("%d new packets at nic %d nm %d tail %d",
n,
adapter->next_rx_desc_to_check,
netmap_idx_n2k(kring, adapter->next_rx_desc_to_check),
kring->nr_hwtail);
adapter->next_rx_desc_to_check = nic_i;
// if_inc_counter(ifp, IFCOUNTER_IPACKETS, n);
kring->nr_hwtail = nm_i;
}
kring->nr_kflags &= ~NKR_PENDINTR;
}
/*
* Second part: skip past packets that userspace has released.
*/
nm_i = kring->nr_hwcur;
if (nm_i != head) {
nic_i = netmap_idx_k2n(kring, nm_i);
for (n = 0; nm_i != head; n++) {
struct netmap_slot *slot = &ring->slot[nm_i];
uint64_t paddr;
void *addr = PNMB(na, slot, &paddr);
struct e1000_rx_desc *curr = &adapter->rx_desc_base[nic_i];
struct em_buffer *rxbuf = &adapter->rx_buffer_area[nic_i];
if (addr == NETMAP_BUF_BASE(na)) /* bad buf */
goto ring_reset;
if (slot->flags & NS_BUF_CHANGED) {
/* buffer has changed, reload map */
curr->buffer_addr = htole64(paddr);
netmap_reload_map(na, adapter->rxtag, rxbuf->map, addr);
slot->flags &= ~NS_BUF_CHANGED;
}
curr->status = 0;
bus_dmamap_sync(adapter->rxtag, rxbuf->map,
BUS_DMASYNC_PREREAD);
#ifdef NIC_PARAVIRT
if (csb_mode && csb->host_rxkick_at == nic_i)
do_host_rxkick = 1;
#endif /* NIC_PARAVIRT */
nm_i = nm_next(nm_i, lim);
nic_i = nm_next(nic_i, lim);
}
kring->nr_hwcur = head;
bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
/*
* IMPORTANT: we must leave one free slot in the ring,
* so move nic_i back by one unit
*/
nic_i = nm_prev(nic_i, lim);
#ifdef NIC_PARAVIRT
/* set unconditionally, then also kick if needed */
if (csb)
csb->guest_rdt = nic_i;
if (!csb_mode || do_host_rxkick)
#endif /* NIC_PARAVIRT */
E1000_WRITE_REG(&adapter->hw, E1000_RDT(0), nic_i);
}
return 0;
ring_reset:
return netmap_ring_reinit(kring);
}
static void
lem_netmap_attach(struct adapter *adapter)
{
struct netmap_adapter na;
bzero(&na, sizeof(na));
na.ifp = adapter->ifp;
na.na_flags = NAF_BDG_MAYSLEEP;
na.num_tx_desc = adapter->num_tx_desc;
na.num_rx_desc = adapter->num_rx_desc;
na.nm_txsync = lem_netmap_txsync;
na.nm_rxsync = lem_netmap_rxsync;
na.nm_register = lem_netmap_reg;
na.num_tx_rings = na.num_rx_rings = 1;
netmap_attach(&na);
}
/* end of file */