mlx4: use MOFED 3.0 fast verbs interface for Rx operations

This commit replaces the CQ polling and QP posting functions
(mlx4_rx_burst() only) with a new low level interface to improve
performance.

Signed-off-by: Alex Rosenbaum <alexr@mellanox.com>
Signed-off-by: Gilad Berman <giladb@mellanox.com>
Signed-off-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>

diff --git a/drivers/net/mlx4/mlx4.c b/drivers/net/mlx4/mlx4.c
index cdc679a..1881f5b 100644 (file)
--- a/drivers/net/mlx4/mlx4.c
+++ b/drivers/net/mlx4/mlx4.c
@@ -188,6 +188,8 @@ struct rxq {
        struct ibv_mr *mr; /* Memory Region (for mp). */
        struct ibv_cq *cq; /* Completion Queue. */
        struct ibv_qp *qp; /* Queue Pair. */
+       struct ibv_exp_qp_burst_family *if_qp; /* QP burst interface. */
+       struct ibv_exp_cq_family *if_cq; /* CQ interface. */
        /*
         * Each VLAN ID requires a separate flow steering rule.
         */
@@ -2319,11 +2321,35 @@ rxq_promiscuous_disable(struct rxq *rxq)
 static void
 rxq_cleanup(struct rxq *rxq)
 {
+       struct ibv_exp_release_intf_params params;
+
        DEBUG("cleaning up %p", (void *)rxq);
        if (rxq->sp)
                rxq_free_elts_sp(rxq);
        else
                rxq_free_elts(rxq);
+       if (rxq->if_qp != NULL) {
+               assert(rxq->priv != NULL);
+               assert(rxq->priv->ctx != NULL);
+               assert(rxq->qp != NULL);
+               params = (struct ibv_exp_release_intf_params){
+                       .comp_mask = 0,
+               };
+               claim_zero(ibv_exp_release_intf(rxq->priv->ctx,
+                                               rxq->if_qp,
+                                               &params));
+       }
+       if (rxq->if_cq != NULL) {
+               assert(rxq->priv != NULL);
+               assert(rxq->priv->ctx != NULL);
+               assert(rxq->cq != NULL);
+               params = (struct ibv_exp_release_intf_params){
+                       .comp_mask = 0,
+               };
+               claim_zero(ibv_exp_release_intf(rxq->priv->ctx,
+                                               rxq->if_cq,
+                                               &params));
+       }
        if (rxq->qp != NULL) {
                rxq_promiscuous_disable(rxq);
                rxq_allmulticast_disable(rxq);
@@ -2360,34 +2386,23 @@ mlx4_rx_burst_sp(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n)
        struct rxq_elt_sp (*elts)[rxq->elts_n] = rxq->elts.sp;
        const unsigned int elts_n = rxq->elts_n;
        unsigned int elts_head = rxq->elts_head;
-       struct ibv_wc wcs[pkts_n];
        struct ibv_recv_wr head;
        struct ibv_recv_wr **next = &head.next;
        struct ibv_recv_wr *bad_wr;
-       int ret = 0;
-       int wcs_n;
-       int i;
+       unsigned int i;
+       unsigned int pkts_ret = 0;
+       int ret;
 
        if (unlikely(!rxq->sp))
                return mlx4_rx_burst(dpdk_rxq, pkts, pkts_n);
        if (unlikely(elts == NULL)) /* See RTE_DEV_CMD_SET_MTU. */
                return 0;
-       wcs_n = ibv_poll_cq(rxq->cq, pkts_n, wcs);
-       if (unlikely(wcs_n == 0))
-               return 0;
-       if (unlikely(wcs_n < 0)) {
-               DEBUG("rxq=%p, ibv_poll_cq() failed (wc_n=%d)",
-                     (void *)rxq, wcs_n);
-               return 0;
-       }
-       assert(wcs_n <= (int)pkts_n);
-       /* For each work completion. */
-       for (i = 0; (i != wcs_n); ++i) {
-               struct ibv_wc *wc = &wcs[i];
-               uint64_t wr_id = wc->wr_id;
-               uint32_t len = wc->byte_len;
+       for (i = 0; (i != pkts_n); ++i) {
                struct rxq_elt_sp *elt = &(*elts)[elts_head];
                struct ibv_recv_wr *wr = &elt->wr;
+               uint64_t wr_id = wr->wr_id;
+               unsigned int len;
+               unsigned int pkt_buf_len;
                struct rte_mbuf *pkt_buf = NULL; /* Buffer returned in pkts. */
                struct rte_mbuf **pkt_buf_next = &pkt_buf;
                unsigned int seg_headroom = RTE_PKTMBUF_HEADROOM;
@@ -2398,26 +2413,51 @@ mlx4_rx_burst_sp(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n)
                (void)wr_id;
 #endif
                assert(wr_id < rxq->elts_n);
-               assert(wr_id == wr->wr_id);
                assert(wr->sg_list == elt->sges);
                assert(wr->num_sge == elemof(elt->sges));
                assert(elts_head < rxq->elts_n);
                assert(rxq->elts_head < rxq->elts_n);
-               /* Link completed WRs together for repost. */
-               *next = wr;
-               next = &wr->next;
-               if (unlikely(wc->status != IBV_WC_SUCCESS)) {
-                       /* Whatever, just repost the offending WR. */
-                       DEBUG("rxq=%p, wr_id=%" PRIu64 ": bad work completion"
-                             " status (%d): %s",
-                             (void *)rxq, wc->wr_id, wc->status,
-                             ibv_wc_status_str(wc->status));
+               ret = rxq->if_cq->poll_length(rxq->cq, NULL, NULL);
+               if (unlikely(ret < 0)) {
+                       struct ibv_wc wc;
+                       int wcs_n;
+
+                       DEBUG("rxq=%p, poll_length() failed (ret=%d)",
+                             (void *)rxq, ret);
+                       /* ibv_poll_cq() must be used in case of failure. */
+                       wcs_n = ibv_poll_cq(rxq->cq, 1, &wc);
+                       if (unlikely(wcs_n == 0))
+                               break;
+                       if (unlikely(wcs_n < 0)) {
+                               DEBUG("rxq=%p, ibv_poll_cq() failed (wcs_n=%d)",
+                                     (void *)rxq, wcs_n);
+                               break;
+                       }
+                       assert(wcs_n == 1);
+                       if (unlikely(wc.status != IBV_WC_SUCCESS)) {
+                               /* Whatever, just repost the offending WR. */
+                               DEBUG("rxq=%p, wr_id=%" PRIu64 ": bad work"
+                                     " completion status (%d): %s",
+                                     (void *)rxq, wc.wr_id, wc.status,
+                                     ibv_wc_status_str(wc.status));
 #ifdef MLX4_PMD_SOFT_COUNTERS
-                       /* Increase dropped packets counter. */
-                       ++rxq->stats.idropped;
+                               /* Increment dropped packets counter. */
+                               ++rxq->stats.idropped;
 #endif
-                       goto repost;
+                               /* Link completed WRs together for repost. */
+                               *next = wr;
+                               next = &wr->next;
+                               goto repost;
+                       }
+                       ret = wc.byte_len;
                }
+               if (ret == 0)
+                       break;
+               len = ret;
+               pkt_buf_len = len;
+               /* Link completed WRs together for repost. */
+               *next = wr;
+               next = &wr->next;
                /*
                 * Replace spent segments with new ones, concatenate and
                 * return them as pkt_buf.
@@ -2502,42 +2542,43 @@ mlx4_rx_burst_sp(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n)
                assert(j != 0);
                NB_SEGS(pkt_buf) = j;
                PORT(pkt_buf) = rxq->port_id;
-               PKT_LEN(pkt_buf) = wc->byte_len;
+               PKT_LEN(pkt_buf) = pkt_buf_len;
                pkt_buf->ol_flags = 0;
 
                /* Return packet. */
                *(pkts++) = pkt_buf;
-               ++ret;
+               ++pkts_ret;
 #ifdef MLX4_PMD_SOFT_COUNTERS
                /* Increase bytes counter. */
-               rxq->stats.ibytes += wc->byte_len;
+               rxq->stats.ibytes += pkt_buf_len;
 #endif
 repost:
                if (++elts_head >= elts_n)
                        elts_head = 0;
                continue;
        }
+       if (unlikely(i == 0))
+               return 0;
        *next = NULL;
        /* Repost WRs. */
 #ifdef DEBUG_RECV
-       DEBUG("%p: reposting %d WRs starting from %" PRIu64 " (%p)",
-             (void *)rxq, wcs_n, wcs[0].wr_id, (void *)head.next);
+       DEBUG("%p: reposting %d WRs", (void *)rxq, i);
 #endif
-       i = ibv_post_recv(rxq->qp, head.next, &bad_wr);
-       if (unlikely(i)) {
+       ret = ibv_post_recv(rxq->qp, head.next, &bad_wr);
+       if (unlikely(ret)) {
                /* Inability to repost WRs is fatal. */
                DEBUG("%p: ibv_post_recv(): failed for WR %p: %s",
                      (void *)rxq->priv,
                      (void *)bad_wr,
-                     strerror(i));
+                     strerror(ret));
                abort();
        }
        rxq->elts_head = elts_head;
 #ifdef MLX4_PMD_SOFT_COUNTERS
        /* Increase packets counter. */
-       rxq->stats.ipackets += ret;
+       rxq->stats.ipackets += pkts_ret;
 #endif
-       return ret;
+       return pkts_ret;
 }
 
 /**
@@ -2564,58 +2605,64 @@ mlx4_rx_burst(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n)
        struct rxq_elt (*elts)[rxq->elts_n] = rxq->elts.no_sp;
        const unsigned int elts_n = rxq->elts_n;
        unsigned int elts_head = rxq->elts_head;
-       struct ibv_wc wcs[pkts_n];
-       struct ibv_recv_wr head;
-       struct ibv_recv_wr **next = &head.next;
-       struct ibv_recv_wr *bad_wr;
-       int ret = 0;
-       int wcs_n;
-       int i;
+       struct ibv_sge sges[pkts_n];
+       unsigned int i;
+       unsigned int pkts_ret = 0;
+       int ret;
 
        if (unlikely(rxq->sp))
                return mlx4_rx_burst_sp(dpdk_rxq, pkts, pkts_n);
-       wcs_n = ibv_poll_cq(rxq->cq, pkts_n, wcs);
-       if (unlikely(wcs_n == 0))
-               return 0;
-       if (unlikely(wcs_n < 0)) {
-               DEBUG("rxq=%p, ibv_poll_cq() failed (wc_n=%d)",
-                     (void *)rxq, wcs_n);
-               return 0;
-       }
-       assert(wcs_n <= (int)pkts_n);
-       /* For each work completion. */
-       for (i = 0; (i != wcs_n); ++i) {
-               struct ibv_wc *wc = &wcs[i];
-               uint64_t wr_id = wc->wr_id;
-               uint32_t len = wc->byte_len;
+       for (i = 0; (i != pkts_n); ++i) {
                struct rxq_elt *elt = &(*elts)[elts_head];
                struct ibv_recv_wr *wr = &elt->wr;
+               uint64_t wr_id = wr->wr_id;
+               unsigned int len;
                struct rte_mbuf *seg = (void *)((uintptr_t)elt->sge.addr -
                        WR_ID(wr_id).offset);
                struct rte_mbuf *rep;
 
                /* Sanity checks. */
                assert(WR_ID(wr_id).id < rxq->elts_n);
-               assert(wr_id == wr->wr_id);
                assert(wr->sg_list == &elt->sge);
                assert(wr->num_sge == 1);
                assert(elts_head < rxq->elts_n);
                assert(rxq->elts_head < rxq->elts_n);
-               /* Link completed WRs together for repost. */
-               *next = wr;
-               next = &wr->next;
-               if (unlikely(wc->status != IBV_WC_SUCCESS)) {
-                       /* Whatever, just repost the offending WR. */
-                       DEBUG("rxq=%p, wr_id=%" PRIu32 ": bad work completion"
-                             " status (%d): %s",
-                             (void *)rxq, WR_ID(wr_id).id, wc->status,
-                             ibv_wc_status_str(wc->status));
+               ret = rxq->if_cq->poll_length(rxq->cq, NULL, NULL);
+               if (unlikely(ret < 0)) {
+                       struct ibv_wc wc;
+                       int wcs_n;
+
+                       DEBUG("rxq=%p, poll_length() failed (ret=%d)",
+                             (void *)rxq, ret);
+                       /* ibv_poll_cq() must be used in case of failure. */
+                       wcs_n = ibv_poll_cq(rxq->cq, 1, &wc);
+                       if (unlikely(wcs_n == 0))
+                               break;
+                       if (unlikely(wcs_n < 0)) {
+                               DEBUG("rxq=%p, ibv_poll_cq() failed (wcs_n=%d)",
+                                     (void *)rxq, wcs_n);
+                               break;
+                       }
+                       assert(wcs_n == 1);
+                       if (unlikely(wc.status != IBV_WC_SUCCESS)) {
+                               /* Whatever, just repost the offending WR. */
+                               DEBUG("rxq=%p, wr_id=%" PRIu64 ": bad work"
+                                     " completion status (%d): %s",
+                                     (void *)rxq, wc.wr_id, wc.status,
+                                     ibv_wc_status_str(wc.status));
 #ifdef MLX4_PMD_SOFT_COUNTERS
-                       /* Increase dropped packets counter. */
-                       ++rxq->stats.idropped;
+                               /* Increment dropped packets counter. */
+                               ++rxq->stats.idropped;
 #endif
-                       goto repost;
+                               /* Add SGE to array for repost. */
+                               sges[i] = elt->sge;
+                               goto repost;
+                       }
+                       ret = wc.byte_len;
                }
+               if (ret == 0)
+                       break;
+               len = ret;
                /*
                 * Fetch initial bytes of packet descriptor into a
                 * cacheline while allocating rep.
@@ -2644,6 +2691,9 @@ mlx4_rx_burst(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n)
                         (uintptr_t)rep);
                assert(WR_ID(wr->wr_id).id == WR_ID(wr_id).id);
 
+               /* Add SGE to array for repost. */
+               sges[i] = elt->sge;
+
                /* Update seg information. */
                SET_DATA_OFF(seg, RTE_PKTMBUF_HEADROOM);
                NB_SEGS(seg) = 1;
@@ -2655,37 +2705,36 @@ mlx4_rx_burst(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n)
 
                /* Return packet. */
                *(pkts++) = seg;
-               ++ret;
+               ++pkts_ret;
 #ifdef MLX4_PMD_SOFT_COUNTERS
                /* Increase bytes counter. */
-               rxq->stats.ibytes += wc->byte_len;
+               rxq->stats.ibytes += len;
 #endif
 repost:
                if (++elts_head >= elts_n)
                        elts_head = 0;
                continue;
        }
-       *next = NULL;
+       if (unlikely(i == 0))
+               return 0;
        /* Repost WRs. */
 #ifdef DEBUG_RECV
-       DEBUG("%p: reposting %d WRs starting from %" PRIu32 " (%p)",
-             (void *)rxq, wcs_n, WR_ID(wcs[0].wr_id).id, (void *)head.next);
+       DEBUG("%p: reposting %u WRs", (void *)rxq, i);
 #endif
-       i = ibv_post_recv(rxq->qp, head.next, &bad_wr);
-       if (unlikely(i)) {
+       ret = rxq->if_qp->recv_burst(rxq->qp, sges, i);
+       if (unlikely(ret)) {
                /* Inability to repost WRs is fatal. */
-               DEBUG("%p: ibv_post_recv(): failed for WR %p: %s",
+               DEBUG("%p: recv_burst(): failed (ret=%d)",
                      (void *)rxq->priv,
-                     (void *)bad_wr,
-                     strerror(i));
+                     ret);
                abort();
        }
        rxq->elts_head = elts_head;
 #ifdef MLX4_PMD_SOFT_COUNTERS
        /* Increase packets counter. */
-       rxq->stats.ipackets += ret;
+       rxq->stats.ipackets += pkts_ret;
 #endif
-       return ret;
+       return pkts_ret;
 }
 
 /**
@@ -3019,6 +3068,10 @@ rxq_setup(struct rte_eth_dev *dev, struct rxq *rxq, uint16_t desc,
                .socket = socket
        };
        struct ibv_exp_qp_attr mod;
+       union {
+               struct ibv_exp_query_intf_params params;
+       } attr;
+       enum ibv_exp_query_intf_status status;
        struct ibv_recv_wr *bad_wr;
        struct rte_mbuf *buf;
        int ret = 0;
@@ -3160,6 +3213,28 @@ skip_alloc:
        /* Save port ID. */
        tmpl.port_id = dev->data->port_id;
        DEBUG("%p: RTE port ID: %u", (void *)rxq, tmpl.port_id);
+       attr.params = (struct ibv_exp_query_intf_params){
+               .intf_scope = IBV_EXP_INTF_GLOBAL,
+               .intf = IBV_EXP_INTF_CQ,
+               .obj = tmpl.cq,
+       };
+       tmpl.if_cq = ibv_exp_query_intf(priv->ctx, &attr.params, &status);
+       if (tmpl.if_cq == NULL) {
+               ERROR("%p: CQ interface family query failed with status %d",
+                     (void *)dev, status);
+               goto error;
+       }
+       attr.params = (struct ibv_exp_query_intf_params){
+               .intf_scope = IBV_EXP_INTF_GLOBAL,
+               .intf = IBV_EXP_INTF_QP_BURST,
+               .obj = tmpl.qp,
+       };
+       tmpl.if_qp = ibv_exp_query_intf(priv->ctx, &attr.params, &status);
+       if (tmpl.if_qp == NULL) {
+               ERROR("%p: QP interface family query failed with status %d",
+                     (void *)dev, status);
+               goto error;
+       }
        /* Clean up rxq in case we're reinitializing it. */
        DEBUG("%p: cleaning-up old rxq just in case", (void *)rxq);
        rxq_cleanup(rxq);