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[73.241.150.58]) by smtp.gmail.com with ESMTPSA id b24sm39794104pfo.55.2020.01.20.09.58.24 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 20 Jan 2020 09:58:25 -0800 (PST) Subject: Re: [PATCH] tcp_bbr: improve arithmetic division in bbr_update_bw() To: Wen Yang , Eric Dumazet , davem@davemloft.net Cc: Alexey Kuznetsov , Hideaki YOSHIFUJI , netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <20200120100456.45609-1-wenyang@linux.alibaba.com> From: Eric Dumazet Message-ID: Date: Mon, 20 Jan 2020 09:58:23 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: <20200120100456.45609-1-wenyang@linux.alibaba.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 1/20/20 2:04 AM, Wen Yang wrote: > do_div() does a 64-by-32 division. Use div64_long() instead of it > if the divisor is long, to avoid truncation to 32-bit. > And as a nice side effect also cleans up the function a bit. > Signed-off-by: Eric Dumazet Thanks !