Re: [PATCH v4 05/16] mm/hugetlb: use direct assignment instead of folio_change_private()

[David Hildenbrand (Arm)]

On 9/14/26 04:24, Zi Yan wrote:
> folio_change_private() should be used along with folio_attach_private() and
> folio_detach_private(), where adding and remove ->private content requires
> folio refcount change. add_hugetlb_folio() simply sets folio->private to
> NULL without refcount manipulation. Change it to direct assignment to avoid
> semantic confusion.
> 
> It prepares for a future commit that remove PG_private.

s/remove/removes/

> 
> No functional change intended.
> 
> Assisted-by: LLM
> To: Muchun Song <muchun.song@xxxxxxxxx>
> To: Oscar Salvador <osalvador@xxxxxxx>
> To: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Cc: David Hildenbrand <david@xxxxxxxxxx>
> Cc: linux-mm@xxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Acked-by: Usama Arif <usama.arif@xxxxxxxxx>
> Reviewed-by: Gregory Price (Meta) <gourry@xxxxxxxxxx>
> Signed-off-by: Zi Yan <ziy@xxxxxxxxxx>
> ---
>  mm/hugetlb.c | 7 ++-----
>  1 file changed, 2 insertions(+), 5 deletions(-)
> 
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index d3a0650ff6905..8d551cdaef9db 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -1446,11 +1446,8 @@ void add_hugetlb_folio(struct hstate *h, struct folio *folio,
>  	}
>  
>  	__folio_set_hugetlb(folio);
> -	folio_change_private(folio, NULL);
> -	/*
> -	 * We have to set hugetlb_vmemmap_optimized again as above
> -	 * folio_change_private(folio, NULL) cleared it.
> -	 */
> +	/* Clear all folio->private flags except hugetlb_vmemmap_optimized. */
> +	folio->private = NULL;
>  	folio_set_hugetlb_vmemmap_optimized(folio);
>  
>  	arch_clear_hugetlb_flags(folio);
> 

Acked-by: David Hildenbrand (Arm) <david@xxxxxxxxxx>

-- 
Cheers,

David