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([2a01:4b00:bd21:4f00:7cc6:d3ca:494:116c]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4804d61f1f8sm54540925e9.5.2026.01.24.08.37.43 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 24 Jan 2026 08:37:44 -0800 (PST) Message-ID: Date: Sat, 24 Jan 2026 16:37:43 +0000 Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH liburing 0/2] Add support for IORING_SETUP_SQ_REWIND To: Jens Axboe , io-uring@vger.kernel.org References: <176912275112.522897.5400530813917730862.b4-ty@kernel.dk> <517fc5f0-5e6d-46ef-800d-9ef4428278a1@kernel.dk> <2d2da3b2-74c6-4605-8d13-3f0cdc67191e@kernel.dk> <9c10b8e7-d64c-491a-96b3-fc26863e0dbf@gmail.com> <30ee2371-f82f-4b29-9276-71b8cc12b87d@kernel.dk> Content-Language: en-US From: Pavel Begunkov In-Reply-To: <30ee2371-f82f-4b29-9276-71b8cc12b87d@kernel.dk> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 1/24/26 15:12, Jens Axboe wrote: > On 1/24/26 3:44 AM, Pavel Begunkov wrote: ... >>>> The head should already be zero. Actually, sounds like the get_sqe >>>> hunk from the patch is not needed either. >>> >>> Yeah agree, I think they are both false alarms. Might warrant a comment >>> though. Or maybe we just fold it into io_uring_load_sq_head()? >> >> What I'm implying is that the >> >> + if (!(ring->flags & IORING_SETUP_SQ_REWIND)) >> + head = io_uring_load_sq_head(ring); >> + >> >> change from the original patch for normal 64B _io_uring_get_sqe() >> doesn't seem to be necessary. I need to take a look, but that's >> a good thing since the function is somewhat frequently called and >> inlined. >> >> That would leave __io_uring_flush_sq() to be the only place >> checking the flag, so maybe comments would better to be put >> there. > > If you have time, would you mind checking the current repo and sending a > patch? Looks like I messed up a bit and committed some of these bits > with: I'll take a look a bit later, but removing should be fine unless liburing overwrites the sq head. -- Pavel Begunkov