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[87.12.139.105]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4887e83682fsm279873525e9.7.2026.04.03.04.54.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 03 Apr 2026 04:54:49 -0700 (PDT) Date: Fri, 3 Apr 2026 13:54:45 +0200 From: Stefano Garzarella To: Laurence Rowe Cc: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , virtualization@lists.linux.dev, netdev@vger.kernel.org, Bobby Eshleman Subject: Re: [PATCH net-next v2] vsock: avoid timeout for non-blocking accept() with empty backlog Message-ID: References: <20260402204918.130395-1-laurencerowe@gmail.com> Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: <20260402204918.130395-1-laurencerowe@gmail.com> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: l586HJNdjvcNspZRqhwCNguBNq89Bb-SBRaESTHLjmI_1775217291 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline On Thu, Apr 02, 2026 at 01:49:18PM -0700, Laurence Rowe wrote: >A common pattern in epoll network servers is to eagerly accept all >pending connections from the non-blocking listening socket after >epoll_wait indicates the socket is ready by calling accept in a loop >until EAGAIN is returned indicating that the backlog is empty. > >Scheduling a timeout for a non-blocking accept with an empty backlog >meant AF_VSOCK sockets used by epoll network servers incurred hundreds >of microseconds of additional latency per accept loop compared to >AF_INET or AF_UNIX sockets. > >Signed-off-by: Laurence Rowe >Reviewed-by: Bobby Eshleman >--- > >Patch v2 with feedback from Stefano Garzarella and Bobby Eshleman: > >- Move prepare_to_wait before release_sock to match previous behaviour. > >- Simplify not connected case. Thanks for addressing them, now LGTM! Reviewed-by: Stefano Garzarella