From c8a1a172ae2b4535b57bcf194a731334246a5a35 Mon Sep 17 00:00:00 2001 From: Viacheslav Ovsiienko Date: Wed, 27 Nov 2019 13:06:16 +0000 Subject: [PATCH] net/mlx5: fix legacy inline multi-packet performance The legacy multi-packet write is the feature allowing to put multiple packets into one transmitting descriptor, this feature is supported by only NIC ConnectX-4LX. The number of packets should be limited to provide optimal size descriptor and better performance. Fixes: 18a1c20044c0 ("net/mlx5: implement Tx burst template") Cc: stable@dpdk.org Signed-off-by: Viacheslav Ovsiienko Acked-by: Matan Azrad --- drivers/net/mlx5/mlx5_prm.h | 1 + drivers/net/mlx5/mlx5_rxtx.c | 4 +++- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/net/mlx5/mlx5_prm.h b/drivers/net/mlx5/mlx5_prm.h index 2bac6a74e0..a805363757 100644 --- a/drivers/net/mlx5/mlx5_prm.h +++ b/drivers/net/mlx5/mlx5_prm.h @@ -100,6 +100,7 @@ */ #define MLX5_EMPW_MAX_PACKETS MLX5_TX_COMP_THRESH #define MLX5_MPW_MAX_PACKETS 6 +#define MLX5_MPW_INLINE_MAX_PACKETS 2 /* * Default packet length threshold to be inlined with diff --git a/drivers/net/mlx5/mlx5_rxtx.c b/drivers/net/mlx5/mlx5_rxtx.c index 25d915c8fd..acf0fd794b 100644 --- a/drivers/net/mlx5/mlx5_rxtx.c +++ b/drivers/net/mlx5/mlx5_rxtx.c @@ -4059,7 +4059,9 @@ mlx5_tx_burst_empw_inline(struct mlx5_txq_data *restrict txq, * Limits the amount of packets in one WQE * to improve CQE latency generation. */ - nlim = RTE_MIN(pkts_n, MLX5_EMPW_MAX_PACKETS); + nlim = RTE_MIN(pkts_n, MLX5_TXOFF_CONFIG(MPW) ? + MLX5_MPW_INLINE_MAX_PACKETS : + MLX5_EMPW_MAX_PACKETS); /* Check whether we have minimal amount WQEs */ if (unlikely(loc->wqe_free < ((2 + MLX5_EMPW_MIN_PACKETS + 3) / 4))) -- 2.20.1