Re: [PATCH 6/6] mm: Constify page_count and page_ref_count
From: Anshuman Khandual
Date: Mon Apr 26 2021 - 23:31:51 EST
On 4/17/21 4:45 AM, Matthew Wilcox (Oracle) wrote:
> Now that compound_head() accepts a const struct page pointer, these two
> functions can be marked as not modifying the page pointer they are passed.
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
> ---
> include/linux/page_ref.h | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/page_ref.h b/include/linux/page_ref.h
> index f3318f34fc54..7ad46f45df39 100644
> --- a/include/linux/page_ref.h
> +++ b/include/linux/page_ref.h
> @@ -62,12 +62,12 @@ static inline void __page_ref_unfreeze(struct page *page, int v)
>
> #endif
>
> -static inline int page_ref_count(struct page *page)
> +static inline int page_ref_count(const struct page *page)
> {
> return atomic_read(&page->_refcount);
> }
>
> -static inline int page_count(struct page *page)
> +static inline int page_count(const struct page *page)
> {
> return atomic_read(&compound_head(page)->_refcount);
> }
>
Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>