Re: [PATCH v2 2/4] drm/xe/ct: fix xa_store() error checking

["Nilawar, Badal" <badal.nilawar@intel.com>]

On 01-10-2024 14:13, Matthew Auld wrote:
> Looks like we are meant to use xa_err() to extract the error encoded in
> the ptr.
> 
> Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
> Signed-off-by: Matthew Auld <matthew.auld@intel.com>
> Cc: Matthew Brost <matthew.brost@intel.com>
> Cc: Badal Nilawar <badal.nilawar@intel.com>
> Cc: <stable@vger.kernel.org> # v6.8+
> ---
>   drivers/gpu/drm/xe/xe_guc_ct.c | 23 ++++++++---------------
>   1 file changed, 8 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_guc_ct.c b/drivers/gpu/drm/xe/xe_guc_ct.c
> index 44263b3cd8c7..d3de2e6d690f 100644
> --- a/drivers/gpu/drm/xe/xe_guc_ct.c
> +++ b/drivers/gpu/drm/xe/xe_guc_ct.c
> @@ -667,16 +667,12 @@ static int __guc_ct_send_locked(struct xe_guc_ct *ct, const u32 *action,
>   		num_g2h = 1;
>   
>   		if (g2h_fence_needs_alloc(g2h_fence)) {
> -			void *ptr;
> -
>   			g2h_fence->seqno = next_ct_seqno(ct, true);
> -			ptr = xa_store(&ct->fence_lookup,
> -				       g2h_fence->seqno,
> -				       g2h_fence, GFP_ATOMIC);
> -			if (IS_ERR(ptr)) {
> -				ret = PTR_ERR(ptr);
> +			ret = xa_err(xa_store(&ct->fence_lookup,
> +					      g2h_fence->seqno, g2h_fence,
> +					      GFP_ATOMIC));
> +			if (ret)
>   				goto out;
> -			}
>   		}
>   
>   		seqno = g2h_fence->seqno;
> @@ -879,14 +875,11 @@ static int guc_ct_send_recv(struct xe_guc_ct *ct, const u32 *action, u32 len,
>   retry_same_fence:
>   	ret = guc_ct_send(ct, action, len, 0, 0, &g2h_fence);
>   	if (unlikely(ret == -ENOMEM)) {
> -		void *ptr;
> -
>   		/* Retry allocation /w GFP_KERNEL */
> -		ptr = xa_store(&ct->fence_lookup,
> -			       g2h_fence.seqno,
> -			       &g2h_fence, GFP_KERNEL);
> -		if (IS_ERR(ptr))
> -			return PTR_ERR(ptr);
> +		ret = xa_err(xa_store(&ct->fence_lookup, g2h_fence.seqno,
> +				      &g2h_fence, GFP_KERNEL));
> +		if (ret)
> +			return ret;

Looks good to me.
Reviewed-by: Badal Nilawar <badal.nilawar@intel.com>

Regards,
Badal

>   
>   		goto retry_same_fence;
>   	} else if (unlikely(ret)) {