net/enic: cap Rx packet processing to end of desc ring

[dpdk.git] / drivers / net / enic / enic_rxtx.c

diff --git a/drivers/net/enic/enic_rxtx.c b/drivers/net/enic/enic_rxtx.c
index e0f93dd..7ae03f3 100644 (file)
--- a/drivers/net/enic/enic_rxtx.c
+++ b/drivers/net/enic/enic_rxtx.c
@@ -310,7 +310,7 @@ enic_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
        struct vnic_rq *rq;
        struct enic *enic = vnic_dev_priv(sop_rq->vdev);
        uint16_t cq_idx;
-       uint16_t rq_idx;
+       uint16_t rq_idx, max_rx;
        uint16_t rq_num;
        struct rte_mbuf *nmb, *rxmb;
        uint16_t nb_rx = 0;
@@ -325,19 +325,23 @@ enic_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
        cq = &enic->cq[enic_cq_rq(enic, sop_rq->index)];
        cq_idx = cq->to_clean;          /* index of cqd, rqd, mbuf_table */
        cqd_ptr = (struct cq_desc *)(cq->ring.descs) + cq_idx;
+       color = cq->last_color;
 
        data_rq = &enic->rq[sop_rq->data_queue_idx];
 
-       while (nb_rx < nb_pkts) {
+       /* Receive until the end of the ring, at most. */
+       max_rx = RTE_MIN(nb_pkts, cq->ring.desc_count - cq_idx);
+
+       while (max_rx) {
                volatile struct rq_enet_desc *rqd_ptr;
                struct cq_desc cqd;
                uint8_t packet_error;
                uint16_t ciflags;
 
+               max_rx--;
+
                /* Check for pkts available */
-               color = (cqd_ptr->type_color >> CQ_DESC_COLOR_SHIFT)
-                       & CQ_DESC_COLOR_MASK;
-               if (color == cq->last_color)
+               if ((cqd_ptr->type_color & CQ_DESC_COLOR_MASK_NOSHIFT) == color)
                        break;
 
                /* Get the cq descriptor and extract rq info from it */
@@ -361,13 +365,7 @@ enic_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
                /* Get the mbuf to return and replace with one just allocated */
                rxmb = rq->mbuf_ring[rq_idx];
                rq->mbuf_ring[rq_idx] = nmb;
-
-               /* Increment cqd, rqd, mbuf_table index */
                cq_idx++;
-               if (unlikely(cq_idx == cq->ring.desc_count)) {
-                       cq_idx = 0;
-                       cq->last_color = cq->last_color ? 0 : 1;
-               }
 
                /* Prefetch next mbuf & desc while processing current one */
                cqd_ptr = (struct cq_desc *)(cq->ring.descs) + cq_idx;
@@ -419,6 +417,7 @@ enic_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
                first_seg->packet_type =
                        enic_cq_rx_flags_to_pkt_type(&cqd, tnl);
                enic_cq_rx_to_pkt_flags(&cqd, first_seg);
+
                /* Wipe the outer types set by enic_cq_rx_flags_to_pkt_type() */
                if (tnl) {
                        first_seg->packet_type &= ~(RTE_PTYPE_L3_MASK |
@@ -438,6 +437,10 @@ enic_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
                /* store the mbuf address into the next entry of the array */
                rx_pkts[nb_rx++] = first_seg;
        }
+       if (unlikely(cq_idx == cq->ring.desc_count)) {
+               cq_idx = 0;
+               cq->last_color ^= CQ_DESC_COLOR_MASK_NOSHIFT;
+       }
 
        sop_rq->pkt_first_seg = first_seg;
        sop_rq->pkt_last_seg = last_seg;