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[185.107.14.3]) by smtp.gmail.com with ESMTPSA id r4sm4064242wmq.10.2021.08.20.00.12.29 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 20 Aug 2021 00:12:30 -0700 (PDT) From: Jesper Dangaard Brouer X-Google-Original-From: Jesper Dangaard Brouer Cc: brouer@redhat.com, hawk@kernel.org, ilias.apalodimas@linaro.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, hkallweit1@gmail.com Subject: Re: [PATCH net-next v2 1/2] page_pool: use relaxed atomic for release side accounting To: Yunsheng Lin , davem@davemloft.net, kuba@kernel.org References: <1629442611-61547-1-git-send-email-linyunsheng@huawei.com> <1629442611-61547-2-git-send-email-linyunsheng@huawei.com> Message-ID: <9363880e-4ed2-5acd-87da-d669b68d0134@redhat.com> Date: Fri, 20 Aug 2021 09:12:29 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <1629442611-61547-2-git-send-email-linyunsheng@huawei.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 20/08/2021 08.56, Yunsheng Lin wrote: > There is no need to synchronize the account updating, so > use the relaxed atomic to avoid some memory barrier in the > data path. > > Signed-off-by: Yunsheng Lin LGTM Acked-by: Jesper Dangaard Brouer > --- > net/core/page_pool.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/core/page_pool.c b/net/core/page_pool.c > index e140905..1a69784 100644 > --- a/net/core/page_pool.c > +++ b/net/core/page_pool.c > @@ -370,7 +370,7 @@ void page_pool_release_page(struct page_pool *pool, struct page *page) > /* This may be the last page returned, releasing the pool, so > * it is not safe to reference pool afterwards. > */ > - count = atomic_inc_return(&pool->pages_state_release_cnt); > + count = atomic_inc_return_relaxed(&pool->pages_state_release_cnt); > trace_page_pool_state_release(pool, page, count); > } > EXPORT_SYMBOL(page_pool_release_page); >