Re: [PATCH] mm: No need to check pcp page when free it to buddy

From: Andrew Morton
Date: Wed Sep 14 2022 - 17:19:28 EST


On Wed, 14 Sep 2022 18:53:40 +0800 "zhaoyang.huang" <zhaoyang.huang@xxxxxxxxxx> wrote:

> From: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx>
>
> The pages on pcp list have been checked the validity from each entrance. It is
> no need to check it again when free them back to buddy.
>

I'm not sure what "from each entrance" means. Please identify the
codesite where this other check is occurring?

> ---
> mm/page_alloc.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index e008a3d..131536e 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -1445,7 +1445,7 @@ static bool free_pcp_prepare(struct page *page, unsigned int order)
>
> static bool bulkfree_pcp_prepare(struct page *page)
> {
> - return check_free_page(page);
> + return false;
> }
> #endif /* CONFIG_DEBUG_VM */