diff mbox series

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

Message ID 20201210194044.876342330@linutronix.de (mailing list archive)
State New
Headers show
Series genirq: Treewide hunt for irq descriptor abuse and assorted fixes | expand

Commit Message

Thomas Gleixner Dec. 10, 2020, 7:25 p.m. UTC
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@linutronix.de>
Cc: Saeed Mahameed <saeedm@nvidia.com>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: netdev@vger.kernel.org
Cc: linux-rdma@vger.kernel.org
---
 drivers/net/ethernet/mellanox/mlx5/core/en_main.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Tariq Toukan Dec. 13, 2020, 11:35 a.m. UTC | #1
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@linutronix.de>
> Cc: Saeed Mahameed <saeedm@nvidia.com>
> Cc: Leon Romanovsky <leon@kernel.org>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Jakub Kicinski <kuba@kernel.org>
> Cc: netdev@vger.kernel.org
> Cc: linux-rdma@vger.kernel.org
> ---
>   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@nvidia.com>

Thanks.
Saeed Mahameed Dec. 14, 2020, 8:58 p.m. UTC | #2
On Thu, 2020-12-10 at 20:25 +0100, 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@linutronix.de>
> Cc: Saeed Mahameed <saeedm@nvidia.com>
> Cc: Leon Romanovsky <leon@kernel.org>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Jakub Kicinski <kuba@kernel.org>
> Cc: netdev@vger.kernel.org
> Cc: linux-rdma@vger.kernel.org
> 

Acked-by: Saeed Mahameed <saeedm@nvidia.com>
diff mbox series

Patch

--- 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);