Re: [patch 23/30] net/mlx5: Use effective interrupt affinity

[Tariq Toukan]

On 12/10/2020 9:25 PM, Thomas Gleixner wrote:
> Using the interrupt affinity mask for checking locality is not really
> working well on architectures which support effective affinity masks.
>
> The affinity mask is either the system wide default or set by user space,
> but the architecture can or even must reduce the mask to the effective set,
> which means that checking the affinity mask itself does not really tell
> about the actual target CPUs.
>
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: Saeed Mahameed <saeedm@xxxxxxxxxx>
> Cc: Leon Romanovsky <leon@xxxxxxxxxx>
> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
> Cc: netdev@xxxxxxxxxxxxxxx
> Cc: linux-rdma@xxxxxxxxxxxxxxx
> ---
>   drivers/net/ethernet/mellanox/mlx5/core/en_main.c |    2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> @@ -1998,7 +1998,7 @@ static int mlx5e_open_channel(struct mlx
>   	c->num_tc   = params->num_tc;
>   	c->xdp      = !!params->xdp_prog;
>   	c->stats    = &priv->channel_stats[ix].ch;
> -	c->aff_mask = irq_get_affinity_mask(irq);
> +	c->aff_mask = irq_get_effective_affinity_mask(irq);
>   	c->lag_port = mlx5e_enumerate_lag_port(priv->mdev, ix);
>   
>   	netif_napi_add(netdev, &c->napi, mlx5e_napi_poll, 64);

Reviewed-by: Tariq Toukan <tariqt@xxxxxxxxxx>

Thanks.