netdev - Re: [PATCH net-next 2/2] net: qed_dev: fix redundant check of rc and against -EINVAL

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Date:   Wed, 20 Oct 2021 10:47:17 +0200
From:   Simon Horman <horms@...nel.org>
To:     Jεan Sacren <sakiwit@...il.com>
Cc:     Ariel Elior <aelior@...vell.com>, GR-everest-linux-l2@...vell.com,
        davem@...emloft.net, kuba@...nel.org, netdev@...r.kernel.org
Subject: Re: [PATCH net-next 2/2] net: qed_dev: fix redundant check of rc and
 against -EINVAL

On Tue, Oct 19, 2021 at 12:26:42AM -0600, Jεan Sacren wrote:
> From: Jean Sacren <sakiwit@...il.com>
> 
> We should first check rc alone and then check it against -EINVAL to
> avoid repeating the same operation multiple times.
> 
> Signed-off-by: Jean Sacren <sakiwit@...il.com>
> ---
>  drivers/net/ethernet/qlogic/qed/qed_dev.c | 35 +++++++++++++----------
>  1 file changed, 20 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/net/ethernet/qlogic/qed/qed_dev.c b/drivers/net/ethernet/qlogic/qed/qed_dev.c
> index 18f3bf7c4dfe..fe8bdb4523b5 100644
> --- a/drivers/net/ethernet/qlogic/qed/qed_dev.c
> +++ b/drivers/net/ethernet/qlogic/qed/qed_dev.c
> @@ -3987,30 +3987,35 @@ static int qed_hw_get_resc(struct qed_hwfn *p_hwfn, struct qed_ptt *p_ptt)
>  				       QED_RESC_LOCK_RESC_ALLOC, false);
>  
>  	rc = qed_mcp_resc_lock(p_hwfn, p_ptt, &resc_lock_params);
> -	if (rc && rc != -EINVAL) {
> -		return rc;
> -	} else if (rc == -EINVAL) {
> +	if (rc) {
> +		if (rc != -EINVAL)
> +			return rc;
> +
>  		DP_INFO(p_hwfn,
>  			"Skip the max values setting of the soft resources since the resource lock is not supported by the MFW\n");
> -	} else if (!rc && !resc_lock_params.b_granted) {
> +	}
> +
> +	if (!resc_lock_params.b_granted) {

Can it be the case where the condition above is met and !rc is false?
If so your patch seems to have changed the logic of this function.

>  		DP_NOTICE(p_hwfn,
>  			  "Failed to acquire the resource lock for the resource allocation commands\n");
>  		return -EBUSY;
> -	} else {
> -		rc = qed_hw_set_soft_resc_size(p_hwfn, p_ptt);
> -		if (rc && rc != -EINVAL) {
> +	}
> +
> +	rc = qed_hw_set_soft_resc_size(p_hwfn, p_ptt);
> +	if (rc) {
> +		if (rc != -EINVAL) {
>  			DP_NOTICE(p_hwfn,
>  				  "Failed to set the max values of the soft resources\n");
>  			goto unlock_and_exit;
> -		} else if (rc == -EINVAL) {
> -			DP_INFO(p_hwfn,
> -				"Skip the max values setting of the soft resources since it is not supported by the MFW\n");
> -			rc = qed_mcp_resc_unlock(p_hwfn, p_ptt,
> -						 &resc_unlock_params);

nit: it looks like the two lines above would now fit on one.

> -			if (rc)
> -				DP_INFO(p_hwfn,
> -					"Failed to release the resource lock for the resource allocation commands\n");
>  		}
> +
> +		DP_INFO(p_hwfn,
> +			"Skip the max values setting of the soft resources since it is not supported by the MFW\n");
> +		rc = qed_mcp_resc_unlock(p_hwfn, p_ptt,
> +					 &resc_unlock_params);
> +		if (rc)
> +			DP_INFO(p_hwfn,
> +				"Failed to release the resource lock for the resource allocation commands\n");
>  	}
>  
>  	rc = qed_hw_set_resc_info(p_hwfn);
>