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Tue, 14 Oct 2025 10:21:20 -0700 (PDT) Message-ID: <0a659c8b-45e4-489e-9b84-fce7600a4beb@kernel.dk> Date: Tue, 14 Oct 2025 11:21:19 -0600 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: Pavel Begunkov , io-uring@vger.kernel.org References: Content-Language: en-US From: Jens Axboe In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit 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. -- Jens Axboe