numam-dpdk/drivers/net/sfc/sfc_ef10_tx.c
Ivan Malov d321954343 net/sfc: free mbufs in bulks on EF10 native Tx reap
Signed-off-by: Ivan Malov <ivan.malov@oktetlabs.ru>
Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
2017-10-06 02:49:48 +02:00

643 lines
17 KiB
C

/*-
* BSD LICENSE
*
* Copyright (c) 2016 Solarflare Communications Inc.
* All rights reserved.
*
* This software was jointly developed between OKTET Labs (under contract
* for Solarflare) and Solarflare Communications, Inc.
*
* 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 COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
*/
#include <stdbool.h>
#include <rte_mbuf.h>
#include <rte_io.h>
#include "efx.h"
#include "efx_types.h"
#include "efx_regs.h"
#include "efx_regs_ef10.h"
#include "sfc_dp_tx.h"
#include "sfc_tweak.h"
#include "sfc_kvargs.h"
#include "sfc_ef10.h"
#define sfc_ef10_tx_err(dpq, ...) \
SFC_DP_LOG(SFC_KVARG_DATAPATH_EF10, ERR, dpq, __VA_ARGS__)
/** Maximum length of the DMA descriptor data */
#define SFC_EF10_TX_DMA_DESC_LEN_MAX \
((1u << ESF_DZ_TX_KER_BYTE_CNT_WIDTH) - 1)
/**
* Maximum number of descriptors/buffers in the Tx ring.
* It should guarantee that corresponding event queue never overfill.
* EF10 native datapath uses event queue of the same size as Tx queue.
* Maximum number of events on datapath can be estimated as number of
* Tx queue entries (one event per Tx buffer in the worst case) plus
* Tx error and flush events.
*/
#define SFC_EF10_TXQ_LIMIT(_ndesc) \
((_ndesc) - 1 /* head must not step on tail */ - \
(SFC_EF10_EV_PER_CACHE_LINE - 1) /* max unused EvQ entries */ - \
1 /* Rx error */ - 1 /* flush */)
struct sfc_ef10_tx_sw_desc {
struct rte_mbuf *mbuf;
};
struct sfc_ef10_txq {
unsigned int flags;
#define SFC_EF10_TXQ_STARTED 0x1
#define SFC_EF10_TXQ_NOT_RUNNING 0x2
#define SFC_EF10_TXQ_EXCEPTION 0x4
unsigned int ptr_mask;
unsigned int added;
unsigned int completed;
unsigned int free_thresh;
unsigned int evq_read_ptr;
struct sfc_ef10_tx_sw_desc *sw_ring;
efx_qword_t *txq_hw_ring;
volatile void *doorbell;
efx_qword_t *evq_hw_ring;
/* Datapath transmit queue anchor */
struct sfc_dp_txq dp;
};
static inline struct sfc_ef10_txq *
sfc_ef10_txq_by_dp_txq(struct sfc_dp_txq *dp_txq)
{
return container_of(dp_txq, struct sfc_ef10_txq, dp);
}
static bool
sfc_ef10_tx_get_event(struct sfc_ef10_txq *txq, efx_qword_t *tx_ev)
{
volatile efx_qword_t *evq_hw_ring = txq->evq_hw_ring;
/*
* Exception flag is set when reap is done.
* It is never done twice per packet burst get and absence of
* the flag is checked on burst get entry.
*/
SFC_ASSERT((txq->flags & SFC_EF10_TXQ_EXCEPTION) == 0);
*tx_ev = evq_hw_ring[txq->evq_read_ptr & txq->ptr_mask];
if (!sfc_ef10_ev_present(*tx_ev))
return false;
if (unlikely(EFX_QWORD_FIELD(*tx_ev, FSF_AZ_EV_CODE) !=
FSE_AZ_EV_CODE_TX_EV)) {
/*
* Do not move read_ptr to keep the event for exception
* handling by the control path.
*/
txq->flags |= SFC_EF10_TXQ_EXCEPTION;
sfc_ef10_tx_err(&txq->dp.dpq,
"TxQ exception at EvQ read ptr %#x",
txq->evq_read_ptr);
return false;
}
txq->evq_read_ptr++;
return true;
}
static unsigned int
sfc_ef10_tx_process_events(struct sfc_ef10_txq *txq)
{
const unsigned int curr_done = txq->completed - 1;
unsigned int anew_done = curr_done;
efx_qword_t tx_ev;
while (sfc_ef10_tx_get_event(txq, &tx_ev)) {
/*
* DROP_EVENT is an internal to the NIC, software should
* never see it and, therefore, may ignore it.
*/
/* Update the latest done descriptor */
anew_done = EFX_QWORD_FIELD(tx_ev, ESF_DZ_TX_DESCR_INDX);
}
return (anew_done - curr_done) & txq->ptr_mask;
}
static void
sfc_ef10_tx_reap(struct sfc_ef10_txq *txq)
{
const unsigned int old_read_ptr = txq->evq_read_ptr;
const unsigned int ptr_mask = txq->ptr_mask;
unsigned int completed = txq->completed;
unsigned int pending = completed;
pending += sfc_ef10_tx_process_events(txq);
if (pending != completed) {
struct rte_mbuf *bulk[SFC_TX_REAP_BULK_SIZE];
unsigned int nb = 0;
do {
struct sfc_ef10_tx_sw_desc *txd;
struct rte_mbuf *m;
txd = &txq->sw_ring[completed & ptr_mask];
if (txd->mbuf == NULL)
continue;
m = rte_pktmbuf_prefree_seg(txd->mbuf);
txd->mbuf = NULL;
if (m == NULL)
continue;
if ((nb == RTE_DIM(bulk)) ||
((nb != 0) && (m->pool != bulk[0]->pool))) {
rte_mempool_put_bulk(bulk[0]->pool,
(void *)bulk, nb);
nb = 0;
}
bulk[nb++] = m;
} while (++completed != pending);
if (nb != 0)
rte_mempool_put_bulk(bulk[0]->pool, (void *)bulk, nb);
txq->completed = completed;
}
sfc_ef10_ev_qclear(txq->evq_hw_ring, ptr_mask, old_read_ptr,
txq->evq_read_ptr);
}
static void
sfc_ef10_tx_qdesc_dma_create(phys_addr_t addr, uint16_t size, bool eop,
efx_qword_t *edp)
{
EFX_POPULATE_QWORD_4(*edp,
ESF_DZ_TX_KER_TYPE, 0,
ESF_DZ_TX_KER_CONT, !eop,
ESF_DZ_TX_KER_BYTE_CNT, size,
ESF_DZ_TX_KER_BUF_ADDR, addr);
}
static inline void
sfc_ef10_tx_qpush(struct sfc_ef10_txq *txq, unsigned int added,
unsigned int pushed)
{
efx_qword_t desc;
efx_oword_t oword;
/*
* This improves performance by pushing a TX descriptor at the same
* time as the doorbell. The descriptor must be added to the TXQ,
* so that can be used if the hardware decides not to use the pushed
* descriptor.
*/
desc.eq_u64[0] = txq->txq_hw_ring[pushed & txq->ptr_mask].eq_u64[0];
EFX_POPULATE_OWORD_3(oword,
ERF_DZ_TX_DESC_WPTR, added & txq->ptr_mask,
ERF_DZ_TX_DESC_HWORD, EFX_QWORD_FIELD(desc, EFX_DWORD_1),
ERF_DZ_TX_DESC_LWORD, EFX_QWORD_FIELD(desc, EFX_DWORD_0));
/* DMA sync to device is not required */
/*
* rte_io_wmb() which guarantees that the STORE operations
* (i.e. Tx and event descriptor updates) that precede
* the rte_io_wmb() call are visible to NIC before the STORE
* operations that follow it (i.e. doorbell write).
*/
rte_io_wmb();
*(volatile __m128i *)txq->doorbell = oword.eo_u128[0];
}
static unsigned int
sfc_ef10_tx_pkt_descs_max(const struct rte_mbuf *m)
{
unsigned int extra_descs_per_seg;
unsigned int extra_descs_per_pkt;
/*
* VLAN offload is not supported yet, so no extra descriptors
* are required for VLAN option descriptor.
*/
/** Maximum length of the mbuf segment data */
#define SFC_MBUF_SEG_LEN_MAX UINT16_MAX
RTE_BUILD_BUG_ON(sizeof(m->data_len) != 2);
/*
* Each segment is already counted once below. So, calculate
* how many extra DMA descriptors may be required per segment in
* the worst case because of maximum DMA descriptor length limit.
* If maximum segment length is less or equal to maximum DMA
* descriptor length, no extra DMA descriptors are required.
*/
extra_descs_per_seg =
(SFC_MBUF_SEG_LEN_MAX - 1) / SFC_EF10_TX_DMA_DESC_LEN_MAX;
/** Maximum length of the packet */
#define SFC_MBUF_PKT_LEN_MAX UINT32_MAX
RTE_BUILD_BUG_ON(sizeof(m->pkt_len) != 4);
/*
* One more limitation on maximum number of extra DMA descriptors
* comes from slicing entire packet because of DMA descriptor length
* limit taking into account that there is at least one segment
* which is already counted below (so division of the maximum
* packet length minus one with round down).
* TSO is not supported yet, so packet length is limited by
* maximum PDU size.
*/
extra_descs_per_pkt =
(RTE_MIN((unsigned int)EFX_MAC_PDU_MAX,
SFC_MBUF_PKT_LEN_MAX) - 1) /
SFC_EF10_TX_DMA_DESC_LEN_MAX;
return m->nb_segs + RTE_MIN(m->nb_segs * extra_descs_per_seg,
extra_descs_per_pkt);
}
static uint16_t
sfc_ef10_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
{
struct sfc_ef10_txq * const txq = sfc_ef10_txq_by_dp_txq(tx_queue);
unsigned int ptr_mask;
unsigned int added;
unsigned int dma_desc_space;
bool reap_done;
struct rte_mbuf **pktp;
struct rte_mbuf **pktp_end;
if (unlikely(txq->flags &
(SFC_EF10_TXQ_NOT_RUNNING | SFC_EF10_TXQ_EXCEPTION)))
return 0;
ptr_mask = txq->ptr_mask;
added = txq->added;
dma_desc_space = SFC_EF10_TXQ_LIMIT(ptr_mask + 1) -
(added - txq->completed);
reap_done = (dma_desc_space < txq->free_thresh);
if (reap_done) {
sfc_ef10_tx_reap(txq);
dma_desc_space = SFC_EF10_TXQ_LIMIT(ptr_mask + 1) -
(added - txq->completed);
}
for (pktp = &tx_pkts[0], pktp_end = &tx_pkts[nb_pkts];
pktp != pktp_end;
++pktp) {
struct rte_mbuf *m_seg = *pktp;
unsigned int pkt_start = added;
uint32_t pkt_len;
if (likely(pktp + 1 != pktp_end))
rte_mbuf_prefetch_part1(pktp[1]);
if (sfc_ef10_tx_pkt_descs_max(m_seg) > dma_desc_space) {
if (reap_done)
break;
/* Push already prepared descriptors before polling */
if (added != txq->added) {
sfc_ef10_tx_qpush(txq, added, txq->added);
txq->added = added;
}
sfc_ef10_tx_reap(txq);
reap_done = true;
dma_desc_space = SFC_EF10_TXQ_LIMIT(ptr_mask + 1) -
(added - txq->completed);
if (sfc_ef10_tx_pkt_descs_max(m_seg) > dma_desc_space)
break;
}
pkt_len = m_seg->pkt_len;
do {
phys_addr_t seg_addr = rte_mbuf_data_dma_addr(m_seg);
unsigned int seg_len = rte_pktmbuf_data_len(m_seg);
unsigned int id = added & ptr_mask;
SFC_ASSERT(seg_len <= SFC_EF10_TX_DMA_DESC_LEN_MAX);
pkt_len -= seg_len;
sfc_ef10_tx_qdesc_dma_create(seg_addr,
seg_len, (pkt_len == 0),
&txq->txq_hw_ring[id]);
/*
* rte_pktmbuf_free() is commonly used in DPDK for
* recycling packets - the function checks every
* segment's reference counter and returns the
* buffer to its pool whenever possible;
* nevertheless, freeing mbuf segments one by one
* may entail some performance decline;
* from this point, sfc_efx_tx_reap() does the same job
* on its own and frees buffers in bulks (all mbufs
* within a bulk belong to the same pool);
* from this perspective, individual segment pointers
* must be associated with the corresponding SW
* descriptors independently so that only one loop
* is sufficient on reap to inspect all the buffers
*/
txq->sw_ring[id].mbuf = m_seg;
++added;
} while ((m_seg = m_seg->next) != 0);
dma_desc_space -= (added - pkt_start);
}
if (likely(added != txq->added)) {
sfc_ef10_tx_qpush(txq, added, txq->added);
txq->added = added;
}
#if SFC_TX_XMIT_PKTS_REAP_AT_LEAST_ONCE
if (!reap_done)
sfc_ef10_tx_reap(txq);
#endif
return pktp - &tx_pkts[0];
}
static void
sfc_ef10_simple_tx_reap(struct sfc_ef10_txq *txq)
{
const unsigned int old_read_ptr = txq->evq_read_ptr;
const unsigned int ptr_mask = txq->ptr_mask;
unsigned int completed = txq->completed;
unsigned int pending = completed;
pending += sfc_ef10_tx_process_events(txq);
if (pending != completed) {
do {
struct sfc_ef10_tx_sw_desc *txd;
txd = &txq->sw_ring[completed & ptr_mask];
rte_pktmbuf_free_seg(txd->mbuf);
} while (++completed != pending);
txq->completed = completed;
}
sfc_ef10_ev_qclear(txq->evq_hw_ring, ptr_mask, old_read_ptr,
txq->evq_read_ptr);
}
static uint16_t
sfc_ef10_simple_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
uint16_t nb_pkts)
{
struct sfc_ef10_txq * const txq = sfc_ef10_txq_by_dp_txq(tx_queue);
unsigned int ptr_mask;
unsigned int added;
unsigned int dma_desc_space;
bool reap_done;
struct rte_mbuf **pktp;
struct rte_mbuf **pktp_end;
if (unlikely(txq->flags &
(SFC_EF10_TXQ_NOT_RUNNING | SFC_EF10_TXQ_EXCEPTION)))
return 0;
ptr_mask = txq->ptr_mask;
added = txq->added;
dma_desc_space = SFC_EF10_TXQ_LIMIT(ptr_mask + 1) -
(added - txq->completed);
reap_done = (dma_desc_space < RTE_MAX(txq->free_thresh, nb_pkts));
if (reap_done) {
sfc_ef10_simple_tx_reap(txq);
dma_desc_space = SFC_EF10_TXQ_LIMIT(ptr_mask + 1) -
(added - txq->completed);
}
pktp_end = &tx_pkts[MIN(nb_pkts, dma_desc_space)];
for (pktp = &tx_pkts[0]; pktp != pktp_end; ++pktp) {
struct rte_mbuf *pkt = *pktp;
unsigned int id = added & ptr_mask;
SFC_ASSERT(rte_pktmbuf_data_len(pkt) <=
SFC_EF10_TX_DMA_DESC_LEN_MAX);
sfc_ef10_tx_qdesc_dma_create(rte_mbuf_data_dma_addr(pkt),
rte_pktmbuf_data_len(pkt),
true, &txq->txq_hw_ring[id]);
txq->sw_ring[id].mbuf = pkt;
++added;
}
if (likely(added != txq->added)) {
sfc_ef10_tx_qpush(txq, added, txq->added);
txq->added = added;
}
#if SFC_TX_XMIT_PKTS_REAP_AT_LEAST_ONCE
if (!reap_done)
sfc_ef10_simple_tx_reap(txq);
#endif
return pktp - &tx_pkts[0];
}
static sfc_dp_tx_qcreate_t sfc_ef10_tx_qcreate;
static int
sfc_ef10_tx_qcreate(uint16_t port_id, uint16_t queue_id,
const struct rte_pci_addr *pci_addr, int socket_id,
const struct sfc_dp_tx_qcreate_info *info,
struct sfc_dp_txq **dp_txqp)
{
struct sfc_ef10_txq *txq;
int rc;
rc = EINVAL;
if (info->txq_entries != info->evq_entries)
goto fail_bad_args;
rc = ENOMEM;
txq = rte_zmalloc_socket("sfc-ef10-txq", sizeof(*txq),
RTE_CACHE_LINE_SIZE, socket_id);
if (txq == NULL)
goto fail_txq_alloc;
sfc_dp_queue_init(&txq->dp.dpq, port_id, queue_id, pci_addr);
rc = ENOMEM;
txq->sw_ring = rte_calloc_socket("sfc-ef10-txq-sw_ring",
info->txq_entries,
sizeof(*txq->sw_ring),
RTE_CACHE_LINE_SIZE, socket_id);
if (txq->sw_ring == NULL)
goto fail_sw_ring_alloc;
txq->flags = SFC_EF10_TXQ_NOT_RUNNING;
txq->ptr_mask = info->txq_entries - 1;
txq->free_thresh = info->free_thresh;
txq->txq_hw_ring = info->txq_hw_ring;
txq->doorbell = (volatile uint8_t *)info->mem_bar +
ER_DZ_TX_DESC_UPD_REG_OFST +
info->hw_index * ER_DZ_TX_DESC_UPD_REG_STEP;
txq->evq_hw_ring = info->evq_hw_ring;
*dp_txqp = &txq->dp;
return 0;
fail_sw_ring_alloc:
rte_free(txq);
fail_txq_alloc:
fail_bad_args:
return rc;
}
static sfc_dp_tx_qdestroy_t sfc_ef10_tx_qdestroy;
static void
sfc_ef10_tx_qdestroy(struct sfc_dp_txq *dp_txq)
{
struct sfc_ef10_txq *txq = sfc_ef10_txq_by_dp_txq(dp_txq);
rte_free(txq->sw_ring);
rte_free(txq);
}
static sfc_dp_tx_qstart_t sfc_ef10_tx_qstart;
static int
sfc_ef10_tx_qstart(struct sfc_dp_txq *dp_txq, unsigned int evq_read_ptr,
unsigned int txq_desc_index)
{
struct sfc_ef10_txq *txq = sfc_ef10_txq_by_dp_txq(dp_txq);
txq->evq_read_ptr = evq_read_ptr;
txq->added = txq->completed = txq_desc_index;
txq->flags |= SFC_EF10_TXQ_STARTED;
txq->flags &= ~(SFC_EF10_TXQ_NOT_RUNNING | SFC_EF10_TXQ_EXCEPTION);
return 0;
}
static sfc_dp_tx_qstop_t sfc_ef10_tx_qstop;
static void
sfc_ef10_tx_qstop(struct sfc_dp_txq *dp_txq, unsigned int *evq_read_ptr)
{
struct sfc_ef10_txq *txq = sfc_ef10_txq_by_dp_txq(dp_txq);
txq->flags |= SFC_EF10_TXQ_NOT_RUNNING;
*evq_read_ptr = txq->evq_read_ptr;
}
static sfc_dp_tx_qtx_ev_t sfc_ef10_tx_qtx_ev;
static bool
sfc_ef10_tx_qtx_ev(struct sfc_dp_txq *dp_txq, __rte_unused unsigned int id)
{
__rte_unused struct sfc_ef10_txq *txq = sfc_ef10_txq_by_dp_txq(dp_txq);
SFC_ASSERT(txq->flags & SFC_EF10_TXQ_NOT_RUNNING);
/*
* It is safe to ignore Tx event since we reap all mbufs on
* queue purge anyway.
*/
return false;
}
static sfc_dp_tx_qreap_t sfc_ef10_tx_qreap;
static void
sfc_ef10_tx_qreap(struct sfc_dp_txq *dp_txq)
{
struct sfc_ef10_txq *txq = sfc_ef10_txq_by_dp_txq(dp_txq);
unsigned int completed;
for (completed = txq->completed; completed != txq->added; ++completed) {
struct sfc_ef10_tx_sw_desc *txd;
txd = &txq->sw_ring[completed & txq->ptr_mask];
if (txd->mbuf != NULL) {
rte_pktmbuf_free(txd->mbuf);
txd->mbuf = NULL;
}
}
txq->flags &= ~SFC_EF10_TXQ_STARTED;
}
static sfc_dp_tx_qdesc_status_t sfc_ef10_tx_qdesc_status;
static int
sfc_ef10_tx_qdesc_status(__rte_unused struct sfc_dp_txq *dp_txq,
__rte_unused uint16_t offset)
{
return -ENOTSUP;
}
struct sfc_dp_tx sfc_ef10_tx = {
.dp = {
.name = SFC_KVARG_DATAPATH_EF10,
.type = SFC_DP_TX,
.hw_fw_caps = SFC_DP_HW_FW_CAP_EF10,
},
.features = SFC_DP_TX_FEAT_MULTI_SEG |
SFC_DP_TX_FEAT_MULTI_PROCESS,
.qcreate = sfc_ef10_tx_qcreate,
.qdestroy = sfc_ef10_tx_qdestroy,
.qstart = sfc_ef10_tx_qstart,
.qtx_ev = sfc_ef10_tx_qtx_ev,
.qstop = sfc_ef10_tx_qstop,
.qreap = sfc_ef10_tx_qreap,
.qdesc_status = sfc_ef10_tx_qdesc_status,
.pkt_burst = sfc_ef10_xmit_pkts,
};
struct sfc_dp_tx sfc_ef10_simple_tx = {
.dp = {
.name = SFC_KVARG_DATAPATH_EF10_SIMPLE,
.type = SFC_DP_TX,
},
.features = SFC_DP_TX_FEAT_MULTI_PROCESS,
.qcreate = sfc_ef10_tx_qcreate,
.qdestroy = sfc_ef10_tx_qdestroy,
.qstart = sfc_ef10_tx_qstart,
.qtx_ev = sfc_ef10_tx_qtx_ev,
.qstop = sfc_ef10_tx_qstop,
.qreap = sfc_ef10_tx_qreap,
.qdesc_status = sfc_ef10_tx_qdesc_status,
.pkt_burst = sfc_ef10_simple_xmit_pkts,
};