Fix one issue in virtio TX: it needs one more vring entry to hold the virtio
header when transmitting packets, it is used later to determine whether to free
more entries from used vring.
Signed-off-by: Changchun Ouyang <changchun.ouyang at intel.com>
Reviewed-by: Huawei Xie <huawei.xie at intel.com>
Tested-by: Jingguo Fu <jingguox.fu at intel.com>
---
lib/librte_pmd_virtio/virtio_rxtx.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/lib/librte_pmd_virtio/virtio_rxtx.c
b/lib/librte_pmd_virtio/virtio_rxtx.c
index 0b10108..b1c189c 100644
--- a/lib/librte_pmd_virtio/virtio_rxtx.c
+++ b/lib/librte_pmd_virtio/virtio_rxtx.c
@@ -699,7 +699,8 @@ virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
uint16_t nb_pkts)
num = (uint16_t)(likely(nb_used < VIRTIO_MBUF_BURST_SZ) ? nb_used :
VIRTIO_MBUF_BURST_SZ);
while (nb_tx < nb_pkts) {
- int need = tx_pkts[nb_tx]->pkt.nb_segs - txvq->vq_free_cnt;
+ /* Need one more entry for virtio header. */
+ int need = tx_pkts[nb_tx]->pkt.nb_segs - txvq->vq_free_cnt + 1;
int deq_cnt = RTE_MIN(need, (int)num);
num -= (deq_cnt > 0) ? deq_cnt : 0;
--
1.8.4.2
