[dpdk-dev] [PATCH] net/mlx5: fix updating total length of multi-packet send

[Yongseok Koh]

The total length field in descriptor of inlined multi-packet send must be
updated before closing a seesion. There's possibility of updating it
afterward. This bug might cause one packet out of MLX5_MPW_DSEG_MAX gets
silently dropped by HW and impact performance, escpecially lossless test.

Fixes: 230189d9ff22 ("net/mlx5: support multi-packet send")
CC: stable at dpdk.org

Signed-off-by: Yongseok Koh <yskoh at mellanox.com>
---
 drivers/net/mlx5/mlx5_rxtx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/mlx5/mlx5_rxtx.c b/drivers/net/mlx5/mlx5_rxtx.c
index 94fe74763..1043ebbc0 100644
--- a/drivers/net/mlx5/mlx5_rxtx.c
+++ b/drivers/net/mlx5/mlx5_rxtx.c
@@ -1046,6 +1046,7 @@ mlx5_tx_burst_mpw_inline(void *dpdk_txq, struct rte_mbuf **pkts,
 					mpw.data.raw += length;
 			}
 			++mpw.pkts_n;
+			mpw.total_len += length;
 			++j;
 			if (mpw.pkts_n == MLX5_MPW_DSEG_MAX) {
 				mlx5_mpw_inline_close(txq, &mpw);
@@ -1055,7 +1056,6 @@ mlx5_tx_burst_mpw_inline(void *dpdk_txq, struct rte_mbuf **pkts,
 				inline_room -= length;
 			}
 		}
-		mpw.total_len += length;
 		elts_head = elts_head_next;
 #ifdef MLX5_PMD_SOFT_COUNTERS
 		/* Increment sent bytes counter. */
-- 
2.11.0