Re: [PATCH v3 4/6] mm/hugetlb: add hugetlb_set_folio_subpool() helper

[Mike Kravetz <mike.kravetz@oracle.com>]

On 09/08/22 12:37, Sidhartha Kumar wrote:
> Allows hugetlb subpool information to be set through a folio.
> 
> Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
> ---
>  fs/hugetlbfs/inode.c    | 4 ++--
>  include/linux/hugetlb.h | 8 +++++++-
>  2 files changed, 9 insertions(+), 3 deletions(-)

As previously mentioned, I would suggest just combining this with the
previous patch.  Changes look fine.
-- 
Mike Kravetz

> 
> diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
> index c2e9c0cdbd81..d9e08c445e2f 100644
> --- a/fs/hugetlbfs/inode.c
> +++ b/fs/hugetlbfs/inode.c
> @@ -1152,9 +1152,9 @@ static int hugetlbfs_migrate_folio(struct address_space *mapping,
>  		return rc;
>  
>  	if (hugetlb_folio_subpool(src)) {
> -		hugetlb_set_page_subpool(&dst->page,
> +		hugetlb_set_folio_subpool(dst,
>  					hugetlb_folio_subpool(src));
> -		hugetlb_set_page_subpool(&src->page, NULL);
> +		hugetlb_set_folio_subpool(src, NULL);
>  	}
>  
>  	if (mode != MIGRATE_SYNC_NO_COPY)
> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
> index 1e7c4007386e..0bcaca694ab7 100644
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -757,10 +757,16 @@ static inline struct hugepage_subpool *hugetlb_page_subpool(struct page *hpage)
>  	return hugetlb_folio_subpool(page_folio(hpage));
>  }
>  
> +static inline void hugetlb_set_folio_subpool(struct folio *folio,
> +					struct hugepage_subpool *subpool)
> +{
> +	folio_set_private_1(folio, (unsigned long)subpool);
> +}
> +
>  static inline void hugetlb_set_page_subpool(struct page *hpage,
>  					struct hugepage_subpool *subpool)
>  {
> -	set_page_private(hpage + SUBPAGE_INDEX_SUBPOOL, (unsigned long)subpool);
> +	hugetlb_set_folio_subpool(page_folio(hpage), subpool);
>  }
>  
>  static inline struct hstate *hstate_file(struct file *f)
> -- 
> 2.31.1
>