Re: [PATCH] slab: Remove unnecessary call to compound_head() in alloc_from_pcs()

[Harry Yoo <harry.yoo@oracle.com>]

On Mon, Nov 24, 2025 at 02:23:27PM +0000, Matthew Wilcox (Oracle) wrote:
> Each page knows which node it belongs to, so there's no need to
> convert to a folio.
> 
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> ---

Nice observation!

Looks good to me,
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>

>  mm/slub.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/mm/slub.c b/mm/slub.c
> index e4a02586dacf..e6a330e24145 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -5126,7 +5126,7 @@ void *alloc_from_pcs(struct kmem_cache *s, gfp_t gfp, int node)
>  		 * be false because of cpu migration during an unlocked part of
>  		 * the current allocation or previous freeing process.
>  		 */
> -		if (folio_nid(virt_to_folio(object)) != node) {
> +		if (page_to_nid(virt_to_page(object)) != node) {
>  			local_unlock(&s->cpu_sheaves->lock);
>  			return NULL;
>  		}
> -- 
> 2.47.2
> 

-- 
Cheers,
Harry / Hyeonggon