Re: [PATCH v4 1/3] mm/huge_memory: add split_huge_page_to_order()

[David Hildenbrand]

On 30.10.25 02:40, Zi Yan wrote:
> When caller does not supply a list to split_huge_page_to_list_to_order(),
> use split_huge_page_to_order() instead.
>
> Signed-off-by: Zi Yan <ziy@xxxxxxxxxx>
> Acked-by: David Hildenbrand <david@xxxxxxxxxx>
> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx>
> ---
>   include/linux/huge_mm.h | 12 ++++++++++--
>   1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
> index 7698b3542c4f..34f8d8453bf3 100644
> --- a/include/linux/huge_mm.h
> +++ b/include/linux/huge_mm.h
> @@ -381,6 +381,10 @@ static inline int split_huge_page_to_list_to_order(struct page *page, struct lis
>   {
>   	return __split_huge_page_to_list_to_order(page, list, new_order, false);
>   }
> +static inline int split_huge_page_to_order(struct page *page, unsigned int new_order)
> +{
> +	return split_huge_page_to_list_to_order(page, NULL, new_order);
> +}
>   

Scanning this once again, I guess in the future all these interfaces 
should rather be folio-based, and if we want to split at a specific page 
where we want the reference to be held later, pass in a page:

int folio_split_to_order(struct folio *folio, struct page *page,
			 unsigned int new_order);

With the hope that we could end up with all folio split functions to
look similar in that regard ... and remove all the "huge_page" terminology.

Of course, that can be done as cleanups on top, because there seems to 
be quite some inconsistency already.


--
Cheers

David / dhildenb