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Wed, 02 Jul 2025 16:19:09 -0700 (PDT) From: Jens Axboe To: Caleb Sander Mateos Cc: io-uring@vger.kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20250619143435.3474028-1-csander@purestorage.com> References: <20250619143435.3474028-1-csander@purestorage.com> Subject: Re: [PATCH] io_uring/rsrc: skip atomic refcount for uncloned buffers Message-Id: <175149834929.467027.590610605534865564.b4-ty@kernel.dk> Date: Wed, 02 Jul 2025 17:19:09 -0600 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Mailer: b4 0.14.3-dev-d7477 On Thu, 19 Jun 2025 08:34:34 -0600, Caleb Sander Mateos wrote: > io_buffer_unmap() performs an atomic decrement of the io_mapped_ubuf's > reference count in case it has been cloned into another io_ring_ctx's > registered buffer table. This is an expensive operation and unnecessary > in the common case that the io_mapped_ubuf is only registered once. > Load the reference count first and check whether it's 1. In that case, > skip the atomic decrement and immediately free the io_mapped_ubuf. > > [...] Applied, thanks! [1/1] io_uring/rsrc: skip atomic refcount for uncloned buffers commit: daa01d954b13a178c216b6a91f8451a7b83b3bf6 Best regards, -- Jens Axboe