Re: [PATCH 2/4] drm/ttm: do not set NULL to debugfs dentry

["Christian König" <christian.koenig@amd.com>]

Am 11.10.21 um 21:06 schrieb Nirmoy Das:
> For debugfs directory, it is recommended to save the result
> and pass over to next debugfs API for creating debugfs
> files/directories. Error conditions are handled by debugfs APIs.
>
> CC: Christian Koenig <christian.koenig@amd.com>
> CC: Huang Rui <ray.huang@amd.com>
> CC: David Airlie <airlied@linux.ie>
> CC: Daniel Vetter <daniel@ffwll.ch>
>
> Signed-off-by: Nirmoy Das <nirmoy.das@amd.com>

Please also add a comment to ttm_debugfs_root that this can also be an 
ERR_PTR and should not be dereferenced.

Apart from that looks good to me.

Christian.

> ---
>   drivers/gpu/drm/ttm/ttm_device.c | 6 +-----
>   1 file changed, 1 insertion(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/ttm/ttm_device.c b/drivers/gpu/drm/ttm/ttm_device.c
> index be24bb6cefd0..225ae6b0b4c2 100644
> --- a/drivers/gpu/drm/ttm/ttm_device.c
> +++ b/drivers/gpu/drm/ttm/ttm_device.c
> @@ -77,9 +77,6 @@ static int ttm_global_init(void)
>   	si_meminfo(&si);
>
>   	ttm_debugfs_root = debugfs_create_dir("ttm", NULL);
> -	if (IS_ERR(ttm_debugfs_root)) {
> -		ttm_debugfs_root = NULL;
> -	}
>
>   	/* Limit the number of pages in the pool to about 50% of the total
>   	 * system memory.
> @@ -108,8 +105,7 @@ static int ttm_global_init(void)
>   	debugfs_create_atomic_t("buffer_objects", 0444, ttm_debugfs_root,
>   				&glob->bo_count);
>   out:
> -	if (ret && ttm_debugfs_root)
> -		debugfs_remove(ttm_debugfs_root);
> +	debugfs_remove(ttm_debugfs_root);
>   	if (ret)
>   		--ttm_glob_use_count;
>   	mutex_unlock(&ttm_global_mutex);
> --
> 2.32.0
>