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[47.44.98.30]) by smtp.gmail.com with ESMTPSA id 8926c6da1cb9f-50d8f3ab9c9sm3466418173.76.2025.09.02.18.29.40 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 02 Sep 2025 18:29:40 -0700 (PDT) Message-ID: <0be5cd99-9b0d-494a-8648-d767e06eb02d@kernel.dk> Date: Tue, 2 Sep 2025 19:29:39 -0600 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 0/4] io_uring: avoid uring_lock for IORING_SETUP_SINGLE_ISSUER From: Jens Axboe To: Caleb Sander Mateos Cc: linux-kernel@vger.kernel.org References: <20250902220803.1932692-1-csander@purestorage.com> <97fbbd68-cdd1-49fa-82d3-e3714ca70eeb@kernel.dk> Content-Language: en-US In-Reply-To: <97fbbd68-cdd1-49fa-82d3-e3714ca70eeb@kernel.dk> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/2/25 7:28 PM, Jens Axboe wrote: > On 9/2/25 4:07 PM, Caleb Sander Mateos wrote: >> As far as I can tell, setting IORING_SETUP_SINGLE_ISSUER when creating >> an io_uring doesn't actually enable any additional optimizations (aside >> from being a requirement for IORING_SETUP_DEFER_TASKRUN). > > Indeed. It was supposed to enable future optimizations, but they > didn't quite materialize. > >> This series leverages IORING_SETUP_SINGLE_ISSUER's guarantee that only >> one task submits SQEs to skip taking the uring_lock mutex in the >> submission and task work paths. > > Interesting, would indeed be great to kill the lock/unlock for each > submit and local work run. I'll take a closer look at this tomorrow. I just noticed that you forgot to CC io-uring@vger.kernel.org on this posting. Would you mind re-sending and doing that? LKML isn't really useful, for anything really, the key list to CC is the io_uring one. -- Jens Axboe