net/bnxt: fix Rx handling and buffer allocation logic

Even when rx buffer allocation fails, we are wrongly updating
the producer index. This patch fixes that.
Also in case of a buffer allocation failure, reattempt buffer
allocation before the rx handler exits.

Fixes: 2eb53b134aae ("net/bnxt: add initial Rx code")
Cc: stable@dpdk.org
Signed-off-by: Ajit Khaparde <ajit.khaparde@broadcom.com>

diff --git a/drivers/net/bnxt/bnxt_rxr.c b/drivers/net/bnxt/bnxt_rxr.c
index bee67d3..bf9f78a 100644 (file)
--- a/drivers/net/bnxt/bnxt_rxr.c
+++ b/drivers/net/bnxt/bnxt_rxr.c
@@ -391,7 +391,7 @@ static int bnxt_rx_pkt(struct rte_mbuf **rx_pkt,
        rte_prefetch0(mbuf);
 
        if (mbuf == NULL)
-               return -ENOMEM;
+               return -EBUSY;
 
        mbuf->nb_segs = 1;
        mbuf->next = NULL;
@@ -448,13 +448,14 @@ static int bnxt_rx_pkt(struct rte_mbuf **rx_pkt,
        if (bnxt_alloc_rx_data(rxq, rxr, prod)) {
                RTE_LOG(ERR, PMD, "mbuf alloc failed with prod=0x%x\n", prod);
                rc = -ENOMEM;
+               goto rx;
        }
        rxr->rx_prod = prod;
        /*
         * All MBUFs are allocated with the same size under DPDK,
         * no optimization for rx_copy_thresh
         */
-
+rx:
        *rx_pkt = mbuf;
 
 next_rx:
@@ -476,6 +477,7 @@ uint16_t bnxt_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
        struct rx_pkt_cmpl *rxcmp;
        uint16_t prod = rxr->rx_prod;
        uint16_t ag_prod = rxr->ag_prod;
+       int rc = 0;
 
        /* Handle RX burst request */
        while (1) {
@@ -491,7 +493,7 @@ uint16_t bnxt_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
                /* TODO: Avoid magic numbers... */
                if ((CMP_TYPE(rxcmp) & 0x30) == 0x10) {
                        rc = bnxt_rx_pkt(&rx_pkts[nb_rx_pkts], rxq, &raw_cons);
-                       if (likely(!rc))
+                       if (likely(!rc) || rc == -ENOMEM)
                                nb_rx_pkts++;
                        if (rc == -EBUSY)       /* partial completion */
                                break;
@@ -514,6 +516,30 @@ uint16_t bnxt_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
        B_RX_DB(rxr->rx_doorbell, rxr->rx_prod);
        /* Ring the AGG ring DB */
        B_RX_DB(rxr->ag_doorbell, rxr->ag_prod);
+
+       /* Attempt to alloc Rx buf in case of a previous allocation failure. */
+       if (rc == -ENOMEM) {
+               int i;
+
+               for (i = prod; i <= nb_rx_pkts;
+                       i = RING_NEXT(rxr->rx_ring_struct, i)) {
+                       struct bnxt_sw_rx_bd *rx_buf = &rxr->rx_buf_ring[i];
+
+                       /* Buffer already allocated for this index. */
+                       if (rx_buf->mbuf != NULL)
+                               continue;
+
+                       /* This slot is empty. Alloc buffer for Rx */
+                       if (!bnxt_alloc_rx_data(rxq, rxr, i)) {
+                               rxr->rx_prod = i;
+                               B_RX_DB(rxr->rx_doorbell, rxr->rx_prod);
+                       } else {
+                               RTE_LOG(ERR, PMD, "Alloc  mbuf failed\n");
+                               break;
+                       }
+               }
+       }
+
        return nb_rx_pkts;
 }