net/virtio: fix packets check in mergeable packed Rx

We should check the descriptor state instead of vq's internal
free count (i.e. the number of descriptors that we haven't made
available) for the remaining mergeable packets.

Fixes: a76290c8f1cf ("net/virtio: implement Rx path for packed queues")
Cc: stable@dpdk.org
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>

diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c
index df0fe06..27ead19 100644 (file)
--- a/drivers/net/virtio/virtio_rxtx.c
+++ b/drivers/net/virtio/virtio_rxtx.c
@@ -1881,38 +1881,34 @@ virtio_recv_mergeable_pkts_packed(void *rx_queue,
        while (seg_res != 0) {
                uint16_t rcv_cnt = RTE_MIN((uint16_t)seg_res,
                                        VIRTIO_MBUF_BURST_SZ);
-               if (likely(vq->vq_free_cnt >= rcv_cnt)) {
-                       num = virtqueue_dequeue_burst_rx_packed(vq, rcv_pkts,
-                                       len, rcv_cnt);
-                       uint16_t extra_idx = 0;
-
-                       rcv_cnt = num;
-
-                       while (extra_idx < rcv_cnt) {
-                               rxm = rcv_pkts[extra_idx];
-
-                               rxm->data_off =
-                                       RTE_PKTMBUF_HEADROOM - hdr_size;
-                               rxm->pkt_len = (uint32_t)(len[extra_idx]);
-                               rxm->data_len = (uint16_t)(len[extra_idx]);
+               uint16_t extra_idx = 0;
 
-                               prev->next = rxm;
-                               prev = rxm;
-                               rx_pkts[nb_rx]->pkt_len += len[extra_idx];
-                               extra_idx += 1;
-                       }
-                       seg_res -= rcv_cnt;
-                       if (!seg_res) {
-                               virtio_rx_stats_updated(rxvq, rx_pkts[nb_rx]);
-                               nb_rx++;
-                       }
-               } else {
-                       PMD_RX_LOG(ERR,
-                                       "No enough segments for packet.");
+               rcv_cnt = virtqueue_dequeue_burst_rx_packed(vq, rcv_pkts,
+                               len, rcv_cnt);
+               if (unlikely(rcv_cnt == 0)) {
+                       PMD_RX_LOG(ERR, "No enough segments for packet.");
                        rte_pktmbuf_free(rx_pkts[nb_rx]);
                        rxvq->stats.errors++;
                        break;
                }
+
+               while (extra_idx < rcv_cnt) {
+                       rxm = rcv_pkts[extra_idx];
+
+                       rxm->data_off = RTE_PKTMBUF_HEADROOM - hdr_size;
+                       rxm->pkt_len = (uint32_t)(len[extra_idx]);
+                       rxm->data_len = (uint16_t)(len[extra_idx]);
+
+                       prev->next = rxm;
+                       prev = rxm;
+                       rx_pkts[nb_rx]->pkt_len += len[extra_idx];
+                       extra_idx += 1;
+               }
+               seg_res -= rcv_cnt;
+               if (!seg_res) {
+                       virtio_rx_stats_updated(rxvq, rx_pkts[nb_rx]);
+                       nb_rx++;
+               }
        }
 
        rxvq->stats.packets += nb_rx;