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Sat, 17 Sep 2022 09:50:27 -0700 (PDT) Message-ID: Date: Sat, 17 Sep 2022 10:50:26 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:102.0) Gecko/20100101 Thunderbird/102.2.2 Subject: Re: [RFC PATCH] nvme: request remote is usually not involved for nvme devices Content-Language: en-US To: Liu Song , kbusch@kernel.org, axboe@fb.com, hch@lst.de, sagi@grimberg.me Cc: linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org References: <1663432858-99743-1-git-send-email-liusong@linux.alibaba.com> From: Jens Axboe In-Reply-To: <1663432858-99743-1-git-send-email-liusong@linux.alibaba.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220917_095030_219144_9D1D5C1C X-CRM114-Status: GOOD ( 10.15 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On 9/17/22 10:40 AM, Liu Song wrote: > From: Liu Song > > NVMe devices usually have a 1:1 mapping between "ctx" and "hctx", > so when "nr_ctx" is equal to 1, there is no possibility of remote > request, so the corresponding process can be simplified. If the worry is the call overhead of blk_mq_complete_request_remote(), why don't we just make that available as an inline instead? That seems vastly superior to providing a random shortcut in a driver to avoid calling it. -- Jens Axboe