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Message-ID: <8adb69f3-b0c0-42bf-b386-51b2be76cbb4@davidwei.uk>
Date: Fri, 8 Mar 2024 15:49:58 -0800
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Subject: Re: [PATCH net-next v1] net: page_pool: factor out page_pool recycle
 check
Content-Language: en-GB
To: Mina Almasry <almasrymina@google.com>, netdev@vger.kernel.org,
 linux-kernel@vger.kernel.org
Cc: Jesper Dangaard Brouer <hawk@kernel.org>,
 Ilias Apalodimas <ilias.apalodimas@linaro.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>
References: <20240308204500.1112858-1-almasrymina@google.com>
From: David Wei <dw@davidwei.uk>
In-Reply-To: <20240308204500.1112858-1-almasrymina@google.com>
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On 2024-03-08 12:44, Mina Almasry 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)

Could this be made inline?

> +{
> +	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);
>