From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C8779C4332F for ; Mon, 6 Dec 2021 20:24:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349507AbhLFU1p (ORCPT ); Mon, 6 Dec 2021 15:27:45 -0500 Received: from cloud48395.mywhc.ca ([173.209.37.211]:40056 "EHLO cloud48395.mywhc.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349484AbhLFU1o (ORCPT ); Mon, 6 Dec 2021 15:27:44 -0500 X-Greylist: delayed 2103 seconds by postgrey-1.27 at vger.kernel.org; Mon, 06 Dec 2021 15:27:44 EST Received: from modemcable064.203-130-66.mc.videotron.ca ([66.130.203.64]:37826 helo=[192.168.1.179]) by cloud48395.mywhc.ca with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1muJz5-0000EI-V1; Mon, 06 Dec 2021 14:49:11 -0500 Message-ID: <5a7ddacb6729a401f99bc7da17b3131ad5217c4a.camel@olivierlanglois.net> Subject: Re: [PATCH v2 0/4] allow to skip CQE posting From: Olivier Langlois To: Jens Axboe , io-uring@vger.kernel.org, Pavel Begunkov Date: Mon, 06 Dec 2021 14:49:11 -0500 In-Reply-To: <163777789036.479228.12615656445425738291.b4-ty@kernel.dk> References: <163777789036.479228.12615656445425738291.b4-ty@kernel.dk> Content-Type: text/plain; charset="ISO-8859-1" User-Agent: Evolution 3.42.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - cloud48395.mywhc.ca X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - olivierlanglois.net X-Get-Message-Sender-Via: cloud48395.mywhc.ca: authenticated_id: olivier@olivierlanglois.net X-Authenticated-Sender: cloud48395.mywhc.ca: olivier@olivierlanglois.net X-Source: X-Source-Args: X-Source-Dir: Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On Wed, 2021-11-24 at 11:18 -0700, Jens Axboe wrote: > On Wed, 10 Nov 2021 15:49:30 +0000, Pavel Begunkov wrote: > > It's expensive enough to post an CQE, and there are other > > reasons to want to ignore them, e.g. for link handling and > > it may just be more convenient for the userspace. > > > > Try to cover most of the use cases with one flag. The overhead > > is one "if (cqe->flags & IOSQE_CQE_SKIP_SUCCESS)" check per > > requests and a bit bloated req_set_fail(), should be bearable. > > > > [...] > > Applied, thanks! > > [1/4] io_uring: clean cqe filling functions >       commit: 913a571affedd17239c4d4ea90c8874b32fc2191 > [2/4] io_uring: add option to skip CQE posting >       commit: 04c76b41ca974b508522831441dd7e5b1b59cbb0 > [3/4] io_uring: don't spinlock when not posting CQEs >       commit: 3d4aeb9f98058c3bdfef5286e240cf18c50fee89 > [4/4] io_uring: disable drain with cqe skip >       commit: 5562a8d71aa32ea27133d8b10406b3dcd57c01a5 > > Best regards, Awesome! that set of patches was on my radar and I am very interested in it. If 5.15 or the soon to be released 5.16 is patchable with it, I'll give it a try in my app and I will report back the benefits it got from it... Greetings,