[dpdk-stable] [dpdk-dev] [PATCH v2] net/mlx5: optimize Rx hash fields conversion

[Kevin Traynor]

On 14/01/2020 09:18, Dekel Peled wrote:
> Previous fix added translation of Rx hash fields to PRM format.
> 
> This patch optimizes the fix, to perform value translation only
> if value is not zero.
> In case value is zero, there is no need to translate it.
> 
> Cc: stable at dpdk.org
> 
> Signed-off-by: Dekel Peled <dekelp at mellanox.com>
> Acked-by: Viacheslav Ovsiienko <viacheslavo at mellanox.com>
> 
> ---
> v2: Modify title for clarity, change 'fix' to 'optimize'.
>     Remove the 'Fixes' label. 

Thanks for the effort to categorize it correctly. Even if it's not with
the Fixes tag, can you add a reference in the commit log to the
"Previous fix". It will provide context for someone reading this commit
log and stable maintainer can at check if the previous commit is in a
particular stable branch.

Kevin.

> ---
> 
> ---
>  drivers/net/mlx5/mlx5_rxq.c | 34 +++++++++++++++++++---------------
>  1 file changed, 19 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/net/mlx5/mlx5_rxq.c b/drivers/net/mlx5/mlx5_rxq.c
> index ca25e32..c936a7f 100644
> --- a/drivers/net/mlx5/mlx5_rxq.c
> +++ b/drivers/net/mlx5/mlx5_rxq.c
> @@ -2460,7 +2460,6 @@ struct mlx5_hrxq *
>  		}
>  	} else { /* ind_tbl->type == MLX5_IND_TBL_TYPE_DEVX */
>  		struct mlx5_devx_tir_attr tir_attr;
> -		struct mlx5_rx_hash_field_select *rx_hash_field_select;
>  		uint32_t i;
>  		uint32_t lro = 1;
>  
> @@ -2474,23 +2473,27 @@ struct mlx5_hrxq *
>  		memset(&tir_attr, 0, sizeof(tir_attr));
>  		tir_attr.disp_type = MLX5_TIRC_DISP_TYPE_INDIRECT;
>  		tir_attr.rx_hash_fn = MLX5_RX_HASH_FN_TOEPLITZ;
> -#ifdef HAVE_IBV_DEVICE_TUNNEL_SUPPORT
>  		tir_attr.tunneled_offload_en = !!tunnel;
> -		/* Translate hash_fields bitmap to PRM format. */
> -		rx_hash_field_select = hash_fields & IBV_RX_HASH_INNER ?
> -				       &tir_attr.rx_hash_field_selector_inner :
> -				       &tir_attr.rx_hash_field_selector_outer;
> +		/* If needed, translate hash_fields bitmap to PRM format. */
> +		if (hash_fields) {
> +#ifdef HAVE_IBV_DEVICE_TUNNEL_SUPPORT
> +			struct mlx5_rx_hash_field_select *rx_hash_field_select =
> +					hash_fields & IBV_RX_HASH_INNER ?
> +					&tir_attr.rx_hash_field_selector_inner :
> +					&tir_attr.rx_hash_field_selector_outer;
>  #else
> -		rx_hash_field_select = &tir_attr.rx_hash_field_selector_outer;
> +			struct mlx5_rx_hash_field_select *rx_hash_field_select =
> +					&tir_attr.rx_hash_field_selector_outer;
>  #endif
> -		/* 1 bit: 0: IPv4, 1: IPv6. */
> -		rx_hash_field_select->l3_prot_type =
> -			!!(hash_fields & MLX5_IPV6_IBV_RX_HASH);
> -		/* 1 bit: 0: TCP, 1: UDP. */
> -		rx_hash_field_select->l4_prot_type =
> -			!!(hash_fields & MLX5_UDP_IBV_RX_HASH);
> -		/* Bitmask which sets which fields to use in RX Hash. */
> -		rx_hash_field_select->selected_fields =
> +
> +			/* 1 bit: 0: IPv4, 1: IPv6. */
> +			rx_hash_field_select->l3_prot_type =
> +				!!(hash_fields & MLX5_IPV6_IBV_RX_HASH);
> +			/* 1 bit: 0: TCP, 1: UDP. */
> +			rx_hash_field_select->l4_prot_type =
> +				!!(hash_fields & MLX5_UDP_IBV_RX_HASH);
> +			/* Bitmask which sets which fields to use in RX Hash. */
> +			rx_hash_field_select->selected_fields =
>  			((!!(hash_fields & MLX5_L3_SRC_IBV_RX_HASH)) <<
>  			 MLX5_RX_HASH_FIELD_SELECT_SELECTED_FIELDS_SRC_IP) |
>  			(!!(hash_fields & MLX5_L3_DST_IBV_RX_HASH)) <<
> @@ -2499,6 +2502,7 @@ struct mlx5_hrxq *
>  			 MLX5_RX_HASH_FIELD_SELECT_SELECTED_FIELDS_L4_SPORT |
>  			(!!(hash_fields & MLX5_L4_DST_IBV_RX_HASH)) <<
>  			 MLX5_RX_HASH_FIELD_SELECT_SELECTED_FIELDS_L4_DPORT;
> +		}
>  		if (rxq_ctrl->obj->type == MLX5_RXQ_OBJ_TYPE_DEVX_HAIRPIN)
>  			tir_attr.transport_domain = priv->sh->td->id;
>  		else
>