[dpdk-dev] [PATCH] net/mlx5: do not select legacy MPW implicitly

[Slava Ovsiienko]

> -----Original Message-----
> From: Alexander Kozyrev <akozyrev at mellanox.com>
> Sent: Thursday, June 11, 2020 20:42
> To: dev at dpdk.org
> Cc: stable at dpdk.org; Raslan Darawsheh <rasland at mellanox.com>; Slava
> Ovsiienko <viacheslavo at mellanox.com>
> Subject: [PATCH] net/mlx5: do not select legacy MPW implicitly
> 
> The Legacy MPW (multi-packet write) should not be engaged implicitly.
> We should exclude this function form a Tx burst routine selection process
> unless it is requested specifically by setting the txq_mpw_en devarg.
> Exclude this function from the selection process the same way it is done for
> the Enhanced MPW in the mlx5_select_tx_function() routine.
> 
> Fixes: eb8121ab9dac ("net/mlx5: introduce Tx burst routine template")
> Cc: stable at dpdk.org
> 
> Signed-off-by: Alexander Kozyrev <akozyrev at mellanox.com>
Acked-by: Viacheslav Ovsiienko <viacheslavo at mellanox.com>

> ---
>  drivers/net/mlx5/mlx5_rxtx.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/net/mlx5/mlx5_rxtx.c b/drivers/net/mlx5/mlx5_rxtx.c
> index 6a17a9a..df58af5 100644
> --- a/drivers/net/mlx5/mlx5_rxtx.c
> +++ b/drivers/net/mlx5/mlx5_rxtx.c
> @@ -5542,6 +5542,9 @@ enum mlx5_txcmp_code {
>  			/* Does not meet requested offloads at all. */
>  			continue;
>  		}
> +		if ((olx ^ tmp) & MLX5_TXOFF_CONFIG_MPW)
> +			/* Do not enable legacy MPW if not configured. */
> +			continue;
>  		if ((olx ^ tmp) & MLX5_TXOFF_CONFIG_EMPW)
>  			/* Do not enable eMPW if not configured. */
>  			continue;
> --
> 1.8.3.1