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From: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Date: Mon, 11 Mar 2024 10:31:54 +0200
Message-ID: <CAC_iWj+304K5jDYXpK6NAO_sRtSwt5QJ+dYn0c1PAhKSi-0aSQ@mail.gmail.com>
Subject: Re: [PATCH net-next v1] net: page_pool: factor out page_pool recycle check
To: Mina Almasry <almasrymina@google.com>
Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, 
	Jesper Dangaard Brouer <hawk@kernel.org>, "David S. Miller" <davem@davemloft.net>, 
	Eric Dumazet <edumazet@google.com>, Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>, 
	Yunsheng Lin <linyunsheng@huawei.com>
Content-Type: text/plain; charset="UTF-8"

On Fri, 8 Mar 2024 at 22:45, Mina Almasry <almasrymina@google.com> wrote:
>
> The check is duplicated in 2 places, factor it out into a common helper.
>
> Signed-off-by: Mina Almasry <almasrymina@google.com>
> Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com>
> ---
>  net/core/page_pool.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/net/core/page_pool.c b/net/core/page_pool.c
> index d706fe5548df..dd364d738c00 100644
> --- a/net/core/page_pool.c
> +++ b/net/core/page_pool.c
> @@ -657,6 +657,11 @@ static bool page_pool_recycle_in_cache(struct page *page,
>         return true;
>  }
>
> +static bool __page_pool_page_can_be_recycled(const struct page *page)
> +{
> +       return page_ref_count(page) == 1 && !page_is_pfmemalloc(page);
> +}
> +
>  /* If the page refcnt == 1, this will try to recycle the page.
>   * if PP_FLAG_DMA_SYNC_DEV is set, we'll try to sync the DMA area for
>   * the configured size min(dma_sync_size, pool->max_len).
> @@ -678,7 +683,7 @@ __page_pool_put_page(struct page_pool *pool, struct page *page,
>          * page is NOT reusable when allocated when system is under
>          * some pressure. (page_is_pfmemalloc)
>          */
> -       if (likely(page_ref_count(page) == 1 && !page_is_pfmemalloc(page))) {
> +       if (likely(__page_pool_page_can_be_recycled(page))) {
>                 /* Read barrier done in page_ref_count / READ_ONCE */
>
>                 if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV)
> @@ -793,7 +798,7 @@ static struct page *page_pool_drain_frag(struct page_pool *pool,
>         if (likely(page_pool_unref_page(page, drain_count)))
>                 return NULL;
>
> -       if (page_ref_count(page) == 1 && !page_is_pfmemalloc(page)) {
> +       if (__page_pool_page_can_be_recycled(page)) {
>                 if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV)
>                         page_pool_dma_sync_for_device(pool, page, -1);
>
> --
> 2.44.0.278.ge034bb2e1d-goog
>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>