[dpdk-dev] [PATCH] net/virtio: fix wrong TX pkt length stats

[Zhiyong Yang <zhiyong.yang@intel.com>]

In the function virtqueue_enqueue_xmit(), when can_push == 1 is true,
vtnet_hdr_size is added to pkt_len by calling rte_pktmbuf_prepend.
So, virtio header len should be subtracted before calling stats
function.

Fixes: 58169a9c8153 ("net/virtio: support Tx checksum offload")

Signed-off-by: Zhiyong Yang <zhiyong.yang@intel.com>
---
 drivers/net/virtio/virtio_rxtx.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c
index 609b4138a..bf14f9a99 100644
--- a/drivers/net/virtio/virtio_rxtx.c
+++ b/drivers/net/virtio/virtio_rxtx.c
@@ -1079,6 +1079,12 @@ virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
 		/* Enqueue Packet buffers */
 		virtqueue_enqueue_xmit(txvq, txm, slots, use_indirect, can_push);
 
+		/* In function virtqueue_enqueue_xmit(), when can_push == 1
+		 * is true, vtnet_hdr_size is added to pkt_len of mbuf. So, it
+		 * should be subtracted before calling stats function.
+		 */
+		if (can_push == 1)
+			txm->pkt_len -= txvq->vq->hw->vtnet_hdr_size;
 		txvq->stats.bytes += txm->pkt_len;
 		virtio_update_packet_stats(&txvq->stats, txm);
 	}
-- 
2.13.3