net/mlx4: fix ring wraparound compiler hint
[dpdk.git] / drivers / net / mlx4 / mlx4_rxtx.c
index 38b87a0..3169fe5 100644 (file)
@@ -37,7 +37,6 @@
  */
 
 #include <assert.h>
-#include <inttypes.h>
 #include <stdint.h>
 #include <string.h>
 
@@ -169,6 +168,7 @@ mlx4_txq_complete(struct txq *txq)
                 * Make sure we read the CQE after we read the ownership bit.
                 */
                rte_rmb();
+#ifndef NDEBUG
                if (unlikely((cqe->owner_sr_opcode & MLX4_CQE_OPCODE_MASK) ==
                             MLX4_CQE_OPCODE_ERROR)) {
                        struct mlx4_err_cqe *cqe_err =
@@ -178,6 +178,7 @@ mlx4_txq_complete(struct txq *txq)
                              (void *)txq, cqe_err->vendor_err,
                              cqe_err->syndrome);
                }
+#endif /* NDEBUG */
                /* Get WQE index reported in the CQE. */
                new_index =
                        rte_be_to_cpu_16(cqe->wqe_index) & sq->txbb_cnt_mask;
@@ -200,7 +201,7 @@ mlx4_txq_complete(struct txq *txq)
         * the ring consumer.
         */
        cq->cons_index = cons_index;
-       *cq->set_ci_db = rte_cpu_to_be_32(cq->cons_index & 0xffffff);
+       *cq->set_ci_db = rte_cpu_to_be_32(cq->cons_index & MLX4_CQ_DB_CI_MASK);
        rte_wmb();
        sq->tail = sq->tail + nr_txbbs;
        /* Update the list of packets posted for transmission. */
@@ -236,63 +237,6 @@ mlx4_txq_mb2mp(struct rte_mbuf *buf)
        return buf->pool;
 }
 
-/**
- * Get memory region (MR) <-> memory pool (MP) association from txq->mp2mr[].
- * Add MP to txq->mp2mr[] if it's not registered yet. If mp2mr[] is full,
- * remove an entry first.
- *
- * @param txq
- *   Pointer to Tx queue structure.
- * @param[in] mp
- *   Memory pool for which a memory region lkey must be returned.
- *
- * @return
- *   mr->lkey on success, (uint32_t)-1 on failure.
- */
-uint32_t
-mlx4_txq_mp2mr(struct txq *txq, struct rte_mempool *mp)
-{
-       unsigned int i;
-       struct ibv_mr *mr;
-
-       for (i = 0; (i != RTE_DIM(txq->mp2mr)); ++i) {
-               if (unlikely(txq->mp2mr[i].mp == NULL)) {
-                       /* Unknown MP, add a new MR for it. */
-                       break;
-               }
-               if (txq->mp2mr[i].mp == mp) {
-                       assert(txq->mp2mr[i].lkey != (uint32_t)-1);
-                       assert(txq->mp2mr[i].mr->lkey == txq->mp2mr[i].lkey);
-                       return txq->mp2mr[i].lkey;
-               }
-       }
-       /* Add a new entry, register MR first. */
-       DEBUG("%p: discovered new memory pool \"%s\" (%p)",
-             (void *)txq, mp->name, (void *)mp);
-       mr = mlx4_mp2mr(txq->priv->pd, mp);
-       if (unlikely(mr == NULL)) {
-               DEBUG("%p: unable to configure MR, ibv_reg_mr() failed.",
-                     (void *)txq);
-               return (uint32_t)-1;
-       }
-       if (unlikely(i == RTE_DIM(txq->mp2mr))) {
-               /* Table is full, remove oldest entry. */
-               DEBUG("%p: MR <-> MP table full, dropping oldest entry.",
-                     (void *)txq);
-               --i;
-               claim_zero(ibv_dereg_mr(txq->mp2mr[0].mr));
-               memmove(&txq->mp2mr[0], &txq->mp2mr[1],
-                       (sizeof(txq->mp2mr) - sizeof(txq->mp2mr[0])));
-       }
-       /* Store the new entry. */
-       txq->mp2mr[i].mp = mp;
-       txq->mp2mr[i].mr = mr;
-       txq->mp2mr[i].lkey = mr->lkey;
-       DEBUG("%p: new MR lkey for MP \"%s\" (%p): 0x%08" PRIu32,
-             (void *)txq, mp->name, (void *)mp, txq->mp2mr[i].lkey);
-       return txq->mp2mr[i].lkey;
-}
-
 /**
  * Posts a single work request to a send queue.
  *
@@ -302,7 +246,7 @@ mlx4_txq_mp2mr(struct txq *txq, struct rte_mempool *mp)
  *   Packet to transmit.
  *
  * @return
- *   0 on success, negative errno value otherwise and rte_errno is set.
+ *   0 on success, negative errno value otherwise.
  */
 static inline int
 mlx4_post_send(struct txq *txq, struct rte_mbuf *pkt)
@@ -311,15 +255,17 @@ mlx4_post_send(struct txq *txq, struct rte_mbuf *pkt)
        struct mlx4_wqe_data_seg *dseg;
        struct mlx4_sq *sq = &txq->msq;
        struct rte_mbuf *buf;
+       union {
+               uint32_t flags;
+               uint16_t flags16[2];
+       } srcrb;
        uint32_t head_idx = sq->head & sq->txbb_cnt_mask;
        uint32_t lkey;
        uintptr_t addr;
-       uint32_t srcrb_flags;
        uint32_t owner_opcode = MLX4_OPCODE_SEND;
        uint32_t byte_count;
        int wqe_real_size;
        int nr_txbbs;
-       int rc;
        struct pv *pv = (struct pv *)txq->bounce_buf;
        int pv_counter = 0;
 
@@ -334,8 +280,7 @@ mlx4_post_send(struct txq *txq, struct rte_mbuf *pkt)
        if (((sq->head - sq->tail) + nr_txbbs +
             sq->headroom_txbbs) >= sq->txbb_cnt ||
            nr_txbbs > MLX4_MAX_WQE_TXBBS) {
-               rc = ENOSPC;
-               goto err;
+               return -ENOSPC;
        }
        /* Get the control and data entries of the WQE. */
        ctrl = (struct mlx4_wqe_ctrl_seg *)mlx4_get_send_wqe(sq, head_idx);
@@ -346,11 +291,12 @@ mlx4_post_send(struct txq *txq, struct rte_mbuf *pkt)
                addr = rte_pktmbuf_mtod(buf, uintptr_t);
                rte_prefetch0((volatile void *)addr);
                /* Handle WQE wraparound. */
-               if (unlikely(dseg >= (struct mlx4_wqe_data_seg *)sq->eob))
+               if (dseg >= (struct mlx4_wqe_data_seg *)sq->eob)
                        dseg = (struct mlx4_wqe_data_seg *)sq->buf;
                dseg->addr = rte_cpu_to_be_64(addr);
                /* Memory region key for this memory pool. */
                lkey = mlx4_txq_mp2mr(txq, mlx4_txq_mb2mp(buf));
+#ifndef NDEBUG
                if (unlikely(lkey == (uint32_t)-1)) {
                        /* MR does not exist. */
                        DEBUG("%p: unable to get MP <-> MR association",
@@ -363,9 +309,9 @@ mlx4_post_send(struct txq *txq, struct rte_mbuf *pkt)
                        ctrl->fence_size = (wqe_real_size >> 4) & 0x3f;
                        mlx4_txq_stamp_freed_wqe(sq, head_idx,
                                     (sq->head & sq->txbb_cnt) ? 0 : 1);
-                       rc = EFAULT;
-                       goto err;
+                       return -EFAULT;
                }
+#endif /* NDEBUG */
                dseg->lkey = rte_cpu_to_be_32(lkey);
                if (likely(buf->data_len)) {
                        byte_count = rte_cpu_to_be_32(buf->data_len);
@@ -413,12 +359,6 @@ mlx4_post_send(struct txq *txq, struct rte_mbuf *pkt)
        }
        /* Fill the control parameters for this packet. */
        ctrl->fence_size = (wqe_real_size >> 4) & 0x3f;
-       /*
-        * The caller should prepare "imm" in advance in order to support
-        * VF to VF communication (when the device is a virtual-function
-        * device (VF)).
-        */
-       ctrl->imm = 0;
        /*
         * For raw Ethernet, the SOLICIT flag is used to indicate that no ICRC
         * should be calculated.
@@ -426,12 +366,43 @@ mlx4_post_send(struct txq *txq, struct rte_mbuf *pkt)
        txq->elts_comp_cd -= nr_txbbs;
        if (unlikely(txq->elts_comp_cd <= 0)) {
                txq->elts_comp_cd = txq->elts_comp_cd_init;
-               srcrb_flags = RTE_BE32(MLX4_WQE_CTRL_SOLICIT |
+               srcrb.flags = RTE_BE32(MLX4_WQE_CTRL_SOLICIT |
                                       MLX4_WQE_CTRL_CQ_UPDATE);
        } else {
-               srcrb_flags = RTE_BE32(MLX4_WQE_CTRL_SOLICIT);
+               srcrb.flags = RTE_BE32(MLX4_WQE_CTRL_SOLICIT);
        }
-       ctrl->srcrb_flags = srcrb_flags;
+       /* Enable HW checksum offload if requested */
+       if (txq->csum &&
+           (pkt->ol_flags &
+            (PKT_TX_IP_CKSUM | PKT_TX_TCP_CKSUM | PKT_TX_UDP_CKSUM))) {
+               const uint64_t is_tunneled = (pkt->ol_flags &
+                                             (PKT_TX_TUNNEL_GRE |
+                                              PKT_TX_TUNNEL_VXLAN));
+
+               if (is_tunneled && txq->csum_l2tun) {
+                       owner_opcode |= MLX4_WQE_CTRL_IIP_HDR_CSUM |
+                                       MLX4_WQE_CTRL_IL4_HDR_CSUM;
+                       if (pkt->ol_flags & PKT_TX_OUTER_IP_CKSUM)
+                               srcrb.flags |=
+                                       RTE_BE32(MLX4_WQE_CTRL_IP_HDR_CSUM);
+               } else {
+                       srcrb.flags |= RTE_BE32(MLX4_WQE_CTRL_IP_HDR_CSUM |
+                                               MLX4_WQE_CTRL_TCP_UDP_CSUM);
+               }
+       }
+       if (txq->lb) {
+               /*
+                * Copy destination MAC address to the WQE, this allows
+                * loopback in eSwitch, so that VFs and PF can communicate
+                * with each other.
+                */
+               srcrb.flags16[0] = *(rte_pktmbuf_mtod(pkt, uint16_t *));
+               ctrl->imm = *(rte_pktmbuf_mtod_offset(pkt, uint32_t *,
+                                                     sizeof(uint16_t)));
+       } else {
+               ctrl->imm = 0;
+       }
+       ctrl->srcrb_flags = srcrb.flags;
        /*
         * Make sure descriptor is fully written before
         * setting ownership bit (because HW can start
@@ -443,9 +414,6 @@ mlx4_post_send(struct txq *txq, struct rte_mbuf *pkt)
                                               MLX4_BIT_WQE_OWN : 0));
        sq->head += nr_txbbs;
        return 0;
-err:
-       rte_errno = rc;
-       return -rc;
 }
 
 /**
@@ -538,9 +506,145 @@ stop:
 }
 
 /**
- * DPDK callback for Rx.
+ * Translate Rx completion flags to packet type.
+ *
+ * @param flags
+ *   Rx completion flags returned by mlx4_cqe_flags().
+ *
+ * @return
+ *   Packet type in mbuf format.
+ */
+static inline uint32_t
+rxq_cq_to_pkt_type(uint32_t flags)
+{
+       uint32_t pkt_type;
+
+       if (flags & MLX4_CQE_L2_TUNNEL)
+               pkt_type =
+                       mlx4_transpose(flags,
+                                      MLX4_CQE_L2_TUNNEL_IPV4,
+                                      RTE_PTYPE_L3_IPV4_EXT_UNKNOWN) |
+                       mlx4_transpose(flags,
+                                      MLX4_CQE_STATUS_IPV4_PKT,
+                                      RTE_PTYPE_INNER_L3_IPV4_EXT_UNKNOWN);
+       else
+               pkt_type = mlx4_transpose(flags,
+                                         MLX4_CQE_STATUS_IPV4_PKT,
+                                         RTE_PTYPE_L3_IPV4_EXT_UNKNOWN);
+       return pkt_type;
+}
+
+/**
+ * Translate Rx completion flags to offload flags.
+ *
+ * @param flags
+ *   Rx completion flags returned by mlx4_cqe_flags().
+ * @param csum
+ *   Whether Rx checksums are enabled.
+ * @param csum_l2tun
+ *   Whether Rx L2 tunnel checksums are enabled.
+ *
+ * @return
+ *   Offload flags (ol_flags) in mbuf format.
+ */
+static inline uint32_t
+rxq_cq_to_ol_flags(uint32_t flags, int csum, int csum_l2tun)
+{
+       uint32_t ol_flags = 0;
+
+       if (csum)
+               ol_flags |=
+                       mlx4_transpose(flags,
+                                      MLX4_CQE_STATUS_IP_HDR_CSUM_OK,
+                                      PKT_RX_IP_CKSUM_GOOD) |
+                       mlx4_transpose(flags,
+                                      MLX4_CQE_STATUS_TCP_UDP_CSUM_OK,
+                                      PKT_RX_L4_CKSUM_GOOD);
+       if ((flags & MLX4_CQE_L2_TUNNEL) && csum_l2tun)
+               ol_flags |=
+                       mlx4_transpose(flags,
+                                      MLX4_CQE_L2_TUNNEL_IPOK,
+                                      PKT_RX_IP_CKSUM_GOOD) |
+                       mlx4_transpose(flags,
+                                      MLX4_CQE_L2_TUNNEL_L4_CSUM,
+                                      PKT_RX_L4_CKSUM_GOOD);
+       return ol_flags;
+}
+
+/**
+ * Extract checksum information from CQE flags.
+ *
+ * @param cqe
+ *   Pointer to CQE structure.
+ * @param csum
+ *   Whether Rx checksums are enabled.
+ * @param csum_l2tun
+ *   Whether Rx L2 tunnel checksums are enabled.
+ *
+ * @return
+ *   CQE checksum information.
+ */
+static inline uint32_t
+mlx4_cqe_flags(struct mlx4_cqe *cqe, int csum, int csum_l2tun)
+{
+       uint32_t flags = 0;
+
+       /*
+        * The relevant bits are in different locations on their
+        * CQE fields therefore we can join them in one 32bit
+        * variable.
+        */
+       if (csum)
+               flags = (rte_be_to_cpu_32(cqe->status) &
+                        MLX4_CQE_STATUS_IPV4_CSUM_OK);
+       if (csum_l2tun)
+               flags |= (rte_be_to_cpu_32(cqe->vlan_my_qpn) &
+                         (MLX4_CQE_L2_TUNNEL |
+                          MLX4_CQE_L2_TUNNEL_IPOK |
+                          MLX4_CQE_L2_TUNNEL_L4_CSUM |
+                          MLX4_CQE_L2_TUNNEL_IPV4));
+       return flags;
+}
+
+/**
+ * Poll one CQE from CQ.
  *
- * The following function doesn't manage scattered packets.
+ * @param rxq
+ *   Pointer to the receive queue structure.
+ * @param[out] out
+ *   Just polled CQE.
+ *
+ * @return
+ *   Number of bytes of the CQE, 0 in case there is no completion.
+ */
+static unsigned int
+mlx4_cq_poll_one(struct rxq *rxq, struct mlx4_cqe **out)
+{
+       int ret = 0;
+       struct mlx4_cqe *cqe = NULL;
+       struct mlx4_cq *cq = &rxq->mcq;
+
+       cqe = (struct mlx4_cqe *)mlx4_get_cqe(cq, cq->cons_index);
+       if (!!(cqe->owner_sr_opcode & MLX4_CQE_OWNER_MASK) ^
+           !!(cq->cons_index & cq->cqe_cnt))
+               goto out;
+       /*
+        * Make sure we read CQ entry contents after we've checked the
+        * ownership bit.
+        */
+       rte_rmb();
+       assert(!(cqe->owner_sr_opcode & MLX4_CQE_IS_SEND_MASK));
+       assert((cqe->owner_sr_opcode & MLX4_CQE_OPCODE_MASK) !=
+              MLX4_CQE_OPCODE_ERROR);
+       ret = rte_be_to_cpu_32(cqe->byte_cnt);
+       ++cq->cons_index;
+out:
+       *out = cqe;
+       return ret;
+}
+
+/**
+ * DPDK callback for Rx with scattered packets support.
  *
  * @param dpdk_rxq
  *   Generic pointer to Rx queue structure.
@@ -555,112 +659,121 @@ stop:
 uint16_t
 mlx4_rx_burst(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n)
 {
-       struct rxq *rxq = (struct rxq *)dpdk_rxq;
-       struct rxq_elt (*elts)[rxq->elts_n] = rxq->elts;
-       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 *wr_head = NULL;
-       struct ibv_recv_wr **wr_next = &wr_head;
-       struct ibv_recv_wr *wr_bad = NULL;
-       unsigned int i;
-       unsigned int pkts_ret = 0;
-       int ret;
+       struct rxq *rxq = dpdk_rxq;
+       const uint32_t wr_cnt = (1 << rxq->elts_n) - 1;
+       const uint16_t sges_n = rxq->sges_n;
+       struct rte_mbuf *pkt = NULL;
+       struct rte_mbuf *seg = NULL;
+       unsigned int i = 0;
+       uint32_t rq_ci = rxq->rq_ci << sges_n;
+       int len = 0;
 
-       ret = ibv_poll_cq(rxq->cq, pkts_n, wcs);
-       if (unlikely(ret == 0))
-               return 0;
-       if (unlikely(ret < 0)) {
-               DEBUG("rxq=%p, ibv_poll_cq() failed (wc_n=%d)",
-                     (void *)rxq, ret);
-               return 0;
-       }
-       assert(ret <= (int)pkts_n);
-       /* For each work completion. */
-       for (i = 0; i != (unsigned int)ret; ++i) {
-               struct ibv_wc *wc = &wcs[i];
-               struct rxq_elt *elt = &(*elts)[elts_head];
-               struct ibv_recv_wr *wr = &elt->wr;
-               uint32_t len = wc->byte_len;
-               struct rte_mbuf *seg = elt->buf;
-               struct rte_mbuf *rep;
-
-               /* Sanity checks. */
-               assert(wr->sg_list == &elt->sge);
-               assert(wr->num_sge == 1);
-               assert(elts_head < rxq->elts_n);
-               assert(rxq->elts_head < rxq->elts_n);
-               /*
-                * Fetch initial bytes of packet descriptor into a
-                * cacheline while allocating rep.
-                */
-               rte_mbuf_prefetch_part1(seg);
-               rte_mbuf_prefetch_part2(seg);
-               /* Link completed WRs together for repost. */
-               *wr_next = wr;
-               wr_next = &wr->next;
-               if (unlikely(wc->status != IBV_WC_SUCCESS)) {
-                       /* Whatever, just repost the offending WR. */
-                       DEBUG("rxq=%p: bad work completion status (%d): %s",
-                             (void *)rxq, wc->status,
-                             ibv_wc_status_str(wc->status));
-                       /* Increment dropped packets counter. */
-                       ++rxq->stats.idropped;
-                       goto repost;
-               }
+       while (pkts_n) {
+               struct mlx4_cqe *cqe;
+               uint32_t idx = rq_ci & wr_cnt;
+               struct rte_mbuf *rep = (*rxq->elts)[idx];
+               volatile struct mlx4_wqe_data_seg *scat = &(*rxq->wqes)[idx];
+
+               /* Update the 'next' pointer of the previous segment. */
+               if (pkt)
+                       seg->next = rep;
+               seg = rep;
+               rte_prefetch0(seg);
+               rte_prefetch0(scat);
                rep = rte_mbuf_raw_alloc(rxq->mp);
                if (unlikely(rep == NULL)) {
-                       /*
-                        * Unable to allocate a replacement mbuf,
-                        * repost WR.
-                        */
-                       DEBUG("rxq=%p: can't allocate a new mbuf",
-                             (void *)rxq);
-                       /* Increase out of memory counters. */
                        ++rxq->stats.rx_nombuf;
-                       ++rxq->priv->dev->data->rx_mbuf_alloc_failed;
-                       goto repost;
+                       if (!pkt) {
+                               /*
+                                * No buffers before we even started,
+                                * bail out silently.
+                                */
+                               break;
+                       }
+                       while (pkt != seg) {
+                               assert(pkt != (*rxq->elts)[idx]);
+                               rep = pkt->next;
+                               pkt->next = NULL;
+                               pkt->nb_segs = 1;
+                               rte_mbuf_raw_free(pkt);
+                               pkt = rep;
+                       }
+                       break;
                }
-               /* Reconfigure sge to use rep instead of seg. */
-               elt->sge.addr = (uintptr_t)rep->buf_addr + RTE_PKTMBUF_HEADROOM;
-               assert(elt->sge.lkey == rxq->mr->lkey);
-               elt->buf = rep;
-               /* Update seg information. */
-               seg->data_off = RTE_PKTMBUF_HEADROOM;
-               seg->nb_segs = 1;
-               seg->port = rxq->port_id;
-               seg->next = NULL;
-               seg->pkt_len = len;
+               if (!pkt) {
+                       /* Looking for the new packet. */
+                       len = mlx4_cq_poll_one(rxq, &cqe);
+                       if (!len) {
+                               rte_mbuf_raw_free(rep);
+                               break;
+                       }
+                       if (unlikely(len < 0)) {
+                               /* Rx error, packet is likely too large. */
+                               rte_mbuf_raw_free(rep);
+                               ++rxq->stats.idropped;
+                               goto skip;
+                       }
+                       pkt = seg;
+                       if (rxq->csum | rxq->csum_l2tun) {
+                               uint32_t flags =
+                                       mlx4_cqe_flags(cqe,
+                                                      rxq->csum,
+                                                      rxq->csum_l2tun);
+
+                               pkt->ol_flags =
+                                       rxq_cq_to_ol_flags(flags,
+                                                          rxq->csum,
+                                                          rxq->csum_l2tun);
+                               pkt->packet_type = rxq_cq_to_pkt_type(flags);
+                       } else {
+                               pkt->packet_type = 0;
+                               pkt->ol_flags = 0;
+                       }
+                       pkt->pkt_len = len;
+               }
+               rep->nb_segs = 1;
+               rep->port = rxq->port_id;
+               rep->data_len = seg->data_len;
+               rep->data_off = seg->data_off;
+               (*rxq->elts)[idx] = rep;
+               /*
+                * Fill NIC descriptor with the new buffer. The lkey and size
+                * of the buffers are already known, only the buffer address
+                * changes.
+                */
+               scat->addr = rte_cpu_to_be_64(rte_pktmbuf_mtod(rep, uintptr_t));
+               if (len > seg->data_len) {
+                       len -= seg->data_len;
+                       ++pkt->nb_segs;
+                       ++rq_ci;
+                       continue;
+               }
+               /* The last segment. */
                seg->data_len = len;
-               seg->packet_type = 0;
-               seg->ol_flags = 0;
+               /* Increment bytes counter. */
+               rxq->stats.ibytes += pkt->pkt_len;
                /* Return packet. */
-               *(pkts++) = seg;
-               ++pkts_ret;
-               /* Increase bytes counter. */
-               rxq->stats.ibytes += len;
-repost:
-               if (++elts_head >= elts_n)
-                       elts_head = 0;
-               continue;
+               *(pkts++) = pkt;
+               pkt = NULL;
+               --pkts_n;
+               ++i;
+skip:
+               /* Align consumer index to the next stride. */
+               rq_ci >>= sges_n;
+               ++rq_ci;
+               rq_ci <<= sges_n;
        }
-       if (unlikely(i == 0))
+       if (unlikely(i == 0 && (rq_ci >> sges_n) == rxq->rq_ci))
                return 0;
-       /* Repost WRs. */
-       *wr_next = NULL;
-       assert(wr_head);
-       ret = ibv_post_wq_recv(rxq->wq, wr_head, &wr_bad);
-       if (unlikely(ret)) {
-               /* Inability to repost WRs is fatal. */
-               DEBUG("%p: recv_burst(): failed (ret=%d)",
-                     (void *)rxq->priv,
-                     ret);
-               abort();
-       }
-       rxq->elts_head = elts_head;
-       /* Increase packets counter. */
-       rxq->stats.ipackets += pkts_ret;
-       return pkts_ret;
+       /* Update the consumer index. */
+       rxq->rq_ci = rq_ci >> sges_n;
+       rte_wmb();
+       *rxq->rq_db = rte_cpu_to_be_32(rxq->rq_ci);
+       *rxq->mcq.set_ci_db =
+               rte_cpu_to_be_32(rxq->mcq.cons_index & MLX4_CQ_DB_CI_MASK);
+       /* Increment packets counter. */
+       rxq->stats.ipackets += i;
+       return i;
 }
 
 /**