net/mlx5: Lag, Remove NULL check before dev_{put, hold}

[PATCH] net/mlx5: Lag, Remove NULL check before dev_{put, hold}

Posted by Jiapeng Chong 1 year, 7 months ago

The call netdev_{put, hold} of dev_{put, hold} will check NULL, so there
is no need to check before using dev_{put, hold}, remove it to silence
the warning:

./drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c:1518:2-10: WARNING: NULL check before dev_{put, hold} functions is not needed.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=9361
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c b/drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c
index d0871c46b8c5..a2fd9a84f877 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c
@@ -1514,8 +1514,7 @@ struct net_device *mlx5_lag_get_roce_netdev(struct mlx5_core_dev *dev)
 	} else {
 		ndev = ldev->pf[MLX5_LAG_P1].netdev;
 	}
-	if (ndev)
-		dev_hold(ndev);
+	dev_hold(ndev);
 
 unlock:
 	spin_unlock_irqrestore(&lag_lock, flags);
-- 
2.20.1.7.g153144c

Re: [PATCH] net/mlx5: Lag, Remove NULL check before dev_{put, hold}

Posted by Simon Horman 1 year, 7 months ago

On Wed, Jun 19, 2024 at 11:53:57AM +0800, Jiapeng Chong wrote:
> The call netdev_{put, hold} of dev_{put, hold} will check NULL, so there
> is no need to check before using dev_{put, hold}, remove it to silence
> the warning:
> 
> ./drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c:1518:2-10: WARNING: NULL check before dev_{put, hold} functions is not needed.
> 
> Reported-by: Abaci Robot <abaci@linux.alibaba.com>
> Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=9361
> Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>

Reviewed-by: Simon Horman <horms@kernel.org>

Re: [PATCH] net/mlx5: Lag, Remove NULL check before dev_{put, hold}

Posted by Jakub Kicinski 1 year, 7 months ago

On Wed, 19 Jun 2024 11:53:57 +0800 Jiapeng Chong wrote:
> The call netdev_{put, hold} of dev_{put, hold} will check NULL

s/of/or/

if you're touching this why not convert to netdev_hold() at the same
time?
-- 
pw-bot: au

Re: [PATCH] net/mlx5: Lag, Remove NULL check before dev_{put, hold}

Posted by Tariq Toukan 1 year, 7 months ago


On 19/06/2024 6:53, Jiapeng Chong wrote:
> The call netdev_{put, hold} of dev_{put, hold} will check NULL, so there
> is no need to check before using dev_{put, hold}, remove it to silence
> the warning:
> 
> ./drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c:1518:2-10: WARNING: NULL check before dev_{put, hold} functions is not needed.
> 
> Reported-by: Abaci Robot <abaci@linux.alibaba.com>
> Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=9361
> Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
> ---
>   drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c | 3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c b/drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c
> index d0871c46b8c5..a2fd9a84f877 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c
> @@ -1514,8 +1514,7 @@ struct net_device *mlx5_lag_get_roce_netdev(struct mlx5_core_dev *dev)
>   	} else {
>   		ndev = ldev->pf[MLX5_LAG_P1].netdev;
>   	}
> -	if (ndev)
> -		dev_hold(ndev);
> +	dev_hold(ndev);
>   
>   unlock:
>   	spin_unlock_irqrestore(&lag_lock, flags);

Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Thanks.

Re: [PATCH] net/mlx5: Lag, Remove NULL check before dev_{put, hold}

Posted by David Wei 1 year, 7 months ago

On 2024-06-18 20:53, Jiapeng Chong wrote:
> The call netdev_{put, hold} of dev_{put, hold} will check NULL, so there
> is no need to check before using dev_{put, hold}, remove it to silence
> the warning:
> 
> ./drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c:1518:2-10: WARNING: NULL check before dev_{put, hold} functions is not needed.
> 
> Reported-by: Abaci Robot <abaci@linux.alibaba.com>
> Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=9361
> Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
> ---
>  drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c b/drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c
> index d0871c46b8c5..a2fd9a84f877 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/lag/lag.c
> @@ -1514,8 +1514,7 @@ struct net_device *mlx5_lag_get_roce_netdev(struct mlx5_core_dev *dev)
>  	} else {
>  		ndev = ldev->pf[MLX5_LAG_P1].netdev;
>  	}
> -	if (ndev)
> -		dev_hold(ndev);
> +	dev_hold(ndev);

Looks safe, dev_hold() -> netdev_hold() which checks for ndev.

Reviewed-by: David Wei <dw@davidwei.uk>

>  
>  unlock:
>  	spin_unlock_irqrestore(&lag_lock, flags);