Re: [PATCH 2/3] mm/slub: remove full list manipulation for non-debug slab

[Vlastimil Babka]

On 1/17/24 12:45, Chengming Zhou wrote:
> Since debug slab is processed by free_to_partial_list(), and only debug
> slab which has SLAB_STORE_USER flag would care about the full list, we
> can remove these unrelated full list manipulations from __slab_free().

Well spotted.

> Signed-off-by: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>

Reviewed-by: Vlastimil Babka <vbabka@xxxxxxx>

> ---
>  mm/slub.c | 4 ----
>  1 file changed, 4 deletions(-)
> 
> diff --git a/mm/slub.c b/mm/slub.c
> index 20c03555c97b..f0307e8b4cd2 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -4187,7 +4187,6 @@ static void __slab_free(struct kmem_cache *s, struct slab *slab,
>  	 * then add it.
>  	 */
>  	if (!kmem_cache_has_cpu_partial(s) && unlikely(!prior)) {
> -		remove_full(s, n, slab);
>  		add_partial(n, slab, DEACTIVATE_TO_TAIL);
>  		stat(s, FREE_ADD_PARTIAL);
>  	}
> @@ -4201,9 +4200,6 @@ static void __slab_free(struct kmem_cache *s, struct slab *slab,
>  		 */
>  		remove_partial(n, slab);
>  		stat(s, FREE_REMOVE_PARTIAL);
> -	} else {
> -		/* Slab must be on the full list */
> -		remove_full(s, n, slab);
>  	}
>  
>  	spin_unlock_irqrestore(&n->list_lock, flags);
>