Re: [dpdk-dev] [PATCH v2 3/3] net/mlx5: add jump action support for NIC

[Shahaf Shuler <shahafs@mellanox.com>]

Thursday, March 28, 2019 6:33 PM, Ori Kam:
> Subject: [PATCH v2 3/3] net/mlx5: add jump action support for NIC
> 
> When using Direct Rules we can add actions to jump between tables.
> This is extra useful since rule insertion rate is much higher on other tables
> compared to table zero.
> 
> if no group is selected the rule is added to group 0.
> 
> Signed-off-by: Ori Kam <orika@mellanox.com>
> ---
>  drivers/net/mlx5/mlx5.h         |   6 +
>  drivers/net/mlx5/mlx5_flow.h    |  15 ++-
>  drivers/net/mlx5/mlx5_flow_dv.c | 278
> +++++++++++++++++++++++++++++++++++-----
>  drivers/net/mlx5/mlx5_glue.c    |  13 ++
>  drivers/net/mlx5/mlx5_glue.h    |   1 +
>  5 files changed, 282 insertions(+), 31 deletions(-)
> 

[...]

>  /**
>   * Register the flow matcher.
>   *
> @@ -2784,6 +2952,9 @@ struct field_modify_info modify_tcp[] = {
>  		.match_mask = (void *)&matcher->mask,
>  	};
>  	struct mlx5_flow_tbl_resource *tbl = NULL;
> +#ifndef HAVE_MLX5DV_DR
> +	struct mlx5_flow_tbl_resource tbl_tmp; #endif
> 
>  	/* Lookup from cache. */
>  	LIST_FOREACH(cache_matcher, &priv->matchers, next) { @@ -
> 2805,33 +2976,24 @@ struct field_modify_info modify_tcp[] = {
>  			return 0;
>  		}
>  	}
> -#ifdef HAVE_MLX5DV_DR
> -	if (matcher->egress) {
> -		tbl = &priv->tx_tbl[matcher->group];
> -		if (!tbl->obj)
> -			tbl->obj = mlx5_glue->dr_create_flow_tbl
> -				(priv->tx_ns,
> -				 matcher->group * MLX5_GROUP_FACTOR);
> -	} else {
> -		tbl = &priv->rx_tbl[matcher->group];
> -		if (!tbl->obj)
> -			tbl->obj = mlx5_glue->dr_create_flow_tbl
> -				(priv->rx_ns,
> -				 matcher->group * MLX5_GROUP_FACTOR);
> -	}
> -	if (!tbl->obj)
> -		return rte_flow_error_set(error, ENOMEM,
> -
> RTE_FLOW_ERROR_TYPE_UNSPECIFIED,
> -					  NULL, "cannot create table");
> -
> -	rte_atomic32_inc(&tbl->refcnt);
> -#endif
>  	/* Register new matcher. */
>  	cache_matcher = rte_calloc(__func__, 1, sizeof(*cache_matcher),
> 0);
>  	if (!cache_matcher)
>  		return rte_flow_error_set(error, ENOMEM,
> 
> RTE_FLOW_ERROR_TYPE_UNSPECIFIED, NULL,
>  					  "cannot allocate matcher memory");
> +#ifdef HAVE_MLX5DV_DR
> +	tbl = flow_dv_tbl_resource_get(dev, matcher->group *
> MLX5_GROUP_FACTOR,
> +				       matcher->egress, error);
> +	if (!tbl) {
> +		rte_free(cache_matcher);
> +		return rte_flow_error_set(error, ENOMEM,
> +
> RTE_FLOW_ERROR_TYPE_UNSPECIFIED,
> +					  NULL, "cannot create table");
> +	}
> +#else
> +	tbl = &tbl_tmp;
> +#endif

I suggest to have the HAVE_MLX5DV_DR inside the flow_dv_tbl_resource_get (return NULL if no DR support). 
Then we can have a cleaner code of this function.