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Tsirkin" , Jason Wang , linux-block@vger.kernel.org, virtualization@lists.linux.dev, linux-kernel@vger.kernel.org, io-uring@vger.kernel.org, Joseph Qi References: <20241203121424.19887-1-mengferry@linux.alibaba.com> <0535520b-a6a6-4578-9aca-c698e148004e@linux.alibaba.com> Content-Language: en-US From: Jens Axboe In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 12/17/24 2:00 PM, Stefan Hajnoczi wrote: > On Tue, 17 Dec 2024 at 12:54, Jens Axboe wrote: >> >> On 12/16/24 11:08 PM, Jingbo Xu wrote: >>>> That's why I asked Jens to weigh in on whether there is a generic >>>> block layer solution here. If uring_cmd is faster then maybe a generic >>>> uring_cmd I/O interface can be defined without tying applications to >>>> device-specific commands. Or maybe the traditional io_uring code path >>>> can be optimized so that bypass is no longer attractive. >> >> It's not that the traditional io_uring code path is slower, it's in fact >> basically the same thing. It's that all the other jazz that happens >> below io_uring slows things down, which is why passthrough ends up being >> faster. > > Are you happy with virtio_blk passthrough or do you want a different approach? I think it looks fine. -- Jens Axboe