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([2a01:4b00:bd21:4f00:7cc6:d3ca:494:116c]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-426ce5e1024sm24860259f8f.42.2025.10.14.11.57.00 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 14 Oct 2025 11:57:01 -0700 (PDT) Message-ID: Date: Tue, 14 Oct 2025 19:58:22 +0100 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 2/2] io_uring: introduce non-circular SQ To: Jens Axboe , io-uring@vger.kernel.org References: <0a659c8b-45e4-489e-9b84-fce7600a4beb@kernel.dk> Content-Language: en-US From: Pavel Begunkov In-Reply-To: <0a659c8b-45e4-489e-9b84-fce7600a4beb@kernel.dk> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 10/14/25 18:21, Jens Axboe wrote: > On 10/14/25 4:58 AM, Pavel Begunkov wrote: >> diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h >> index a0cc1cc0dd01..d1c654a7fa9a 100644 >> --- a/include/uapi/linux/io_uring.h >> +++ b/include/uapi/linux/io_uring.h >> @@ -231,6 +231,12 @@ enum io_uring_sqe_flags_bit { >> */ >> #define IORING_SETUP_CQE_MIXED (1U << 18) >> >> +/* >> + * SQEs always start at index 0 in the submission ring instead of using a >> + * wrap around indexing. >> + */ >> +#define IORING_SETUP_SQ_REWIND (1U << 19) > > No real comments on this patch, very straightforward. I do think this > comment should be expanded on considerably, mostly just by adding a > comparison to how it's different from the normal non-rewind way of > tracking which SQEs to submit. I can do it too, or send a v2. Please do if that's fine with you. Not entirely sure how you want to put it into words. -- Pavel Begunkov