Re: [PATCH net-next v9 3/4] skbuff: Add a function to check if a page belongs to page_pool

[Mina Almasry <almasrymina@google.com>]

On Mon, Dec 11, 2023 at 8:47 PM Liang Chen <liangchen.linux@gmail.com> wrote:
>
> Wrap code for checking if a page is a page_pool page into a
> function for better readability and ease of reuse.
>
> Signed-off-by: Liang Chen <liangchen.linux@gmail.com>
> Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com>
> Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

Only 1 nit, feel free to ignore since especially if Jakub wants to
merge the patch asap.

Reviewed-by: Mina Almasry <almasrymina@google.com>

> ---
>  net/core/skbuff.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/net/core/skbuff.c b/net/core/skbuff.c
> index b157efea5dea..7e26b56cda38 100644
> --- a/net/core/skbuff.c
> +++ b/net/core/skbuff.c
> @@ -890,6 +890,11 @@ static void skb_clone_fraglist(struct sk_buff *skb)
>                 skb_get(list);
>  }
>
> +static bool is_pp_page(struct page *page)
> +{
> +       return (page->pp_magic & ~0x3UL) == PP_SIGNATURE;
> +}
> +
>  #if IS_ENABLED(CONFIG_PAGE_POOL)
>  bool napi_pp_put_page(struct page *page, bool napi_safe)
>  {
> @@ -905,7 +910,7 @@ bool napi_pp_put_page(struct page *page, bool napi_safe)
>          * and page_is_pfmemalloc() is checked in __page_pool_put_page()
>          * to avoid recycling the pfmemalloc page.
>          */
> -       if (unlikely((page->pp_magic & ~0x3UL) != PP_SIGNATURE))
> +       if (unlikely(!is_pp_page(page)))

Nit: I think the unlikely here is unnecessary anyway, and can be
removed (if without else is already unlikely).

>                 return false;
>
>         pp = page->pp;
> --
> 2.31.1
>
>


-- 
Thanks,
Mina