Re: [PATCH v3 2/2] mm/mm_slot.h: add comments for mm_slot_lookup/insert

[Lorenzo Stoakes (ARM)]

On Tue, Jul 14, 2026 at 09:28:15AM +0800, xu.xin16@xxxxxxxxxx wrote:
> From: xu xin <xu.xin16@xxxxxxxxxx>
>
> mm_slot_lookup() and mm_slot_insert() are the only helpers in
> this header that are implemented as macros rather than static inline
> functions. This may look inconsistent without explanation.
>
> Explain they must be macros because hash_for_each_possible()
> needs the table as an array (for sizeof), not a pointer.
>
> Signed-off-by: xu xin <xu.xin16@xxxxxxxxxx>

LGTM, so:

Reviewed-by: Lorenzo Stoakes (ARM) <ljs@xxxxxxxxxx>

> ---
>  mm/mm_slot.h | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/mm/mm_slot.h b/mm/mm_slot.h
> index 5de3e91d86b4..9b09b68e5742 100644
> --- a/mm/mm_slot.h
> +++ b/mm/mm_slot.h
> @@ -33,6 +33,12 @@ static inline void mm_slot_free(struct kmem_cache *cache, void *objp)
>  	kmem_cache_free(cache, objp);
>  }
>
> +/*
> + * Note: mm_slot_lookup and mm_slot_insert cannot be converted to static inline
> + * functions because the hash helpers (hash_for_each_possible and hash_add) rely
> + * on the actual array argument 'hashtable' for sizeof() instead of pointers.
> + */
> +
>  #define mm_slot_lookup(_hashtable, _mm) 				       \
>  ({									       \
>  	struct mm_slot *tmp_slot, *mm_slot = NULL;			       \
> --
> 2.25.1