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 X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E08C2C3815B for ; Fri, 17 Apr 2020 17:42:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C7A762220A for ; Fri, 17 Apr 2020 17:42:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="hfCzRr7n" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730154AbgDQRme (ORCPT ); Fri, 17 Apr 2020 13:42:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37118 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1730098AbgDQRmd (ORCPT ); Fri, 17 Apr 2020 13:42:33 -0400 Received: from mail-pj1-x1044.google.com (mail-pj1-x1044.google.com [IPv6:2607:f8b0:4864:20::1044]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 58C6AC061A0F for ; Fri, 17 Apr 2020 10:42:33 -0700 (PDT) Received: by mail-pj1-x1044.google.com with SMTP id 7so2396821pjo.0 for ; Fri, 17 Apr 2020 10:42:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=KjrOit2pYvG6gEqrAeDYI3gE0UdgfpjpULdnfz35SG4=; b=hfCzRr7n9mEYTAzBtGsqWPrXejcBdO5Qow4g1jcQych3gq3xMjtal1xwI1r0Xaltxg yOtWdQuQor/DxpjYesdIWV0ZJ0OS84Rbas3R5Jo6sGHlqZV8IucD609aVErkzYTaozDW iZRPrR2VgmL6QzTT68OtXYFHagWH+Xrq2cJ5T7LGCn65ywk8bJGveZF5ugT8ycyWpad1 gzB9YmagGJgST/YiEpY5nw9TpSElJVBxpla1je6WnVaA7RC1tTXPHwHEln0rgGic2siW kGIgF6hQ1pWO7t16HoW4SP7IVKGatWHYZkn70aDNcWTBQp3kJ1rLWPQRorrfjanJEROC ZAaA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=KjrOit2pYvG6gEqrAeDYI3gE0UdgfpjpULdnfz35SG4=; b=JbcxdJN0P/n/orfp92IIN52YvDeSbOlOg/l9udMAVFy5KDyQWYyTwevEDHEoB6eAR1 CpK3/W1jdYPOeIsL1DSVEG1j+Ep4mVuloPedcKU+PkhlMDueBBLEct82gRpuE13PrPxt MyxnXsg9KDd3FVSSaFLm73CPYHPoKiL7zKIQa/Y+UMrK+2g9dHPiacGAKd8iZ/orD8+y QjOv2yxo+HFGKBycbK+9/8yJGl5vhwQco5wN5CsuOaScJJS7V/tnkFZF+BYGxhKhR6da gwl0Qd3a2CwC1hcz8r3kMIi3P8DQ81sF45pT1E5HvIspZanGj+IAR0Sjs4P7MI8EIjz+ pXNQ== X-Gm-Message-State: AGi0Pua2PlfRBAs2O1TFbXCmn4NSG0KR9wcMfP6J7Dcm2ts+NM5cfyCt Hsbh4jz5wWrusqLli53nVPgLLg== X-Google-Smtp-Source: APiQypKVAurQv52m9wQY/0bAGCeuAPfRMLq4iN/ZNr5XO8b0GoTa0DND2q3neyht7vIzBR1tbdREHA== X-Received: by 2002:a17:90a:364c:: with SMTP id s70mr5685521pjb.143.1587145352627; Fri, 17 Apr 2020 10:42:32 -0700 (PDT) Received: from [192.168.1.188] ([66.219.217.145]) by smtp.gmail.com with ESMTPSA id h15sm13021131pgj.35.2020.04.17.10.42.30 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 17 Apr 2020 10:42:31 -0700 (PDT) Subject: Re: [GIT PULL] io_uring fixes for 5.7-rc To: Linus Torvalds Cc: "linux-kernel@vger.kernel.org" , io-uring References: <2750fd4f-8edc-18c2-1991-c1dc794a431f@kernel.dk> From: Jens Axboe Message-ID: <53ee39ac-2d97-9bcc-80c9-5ed9b0868e8f@kernel.dk> Date: Fri, 17 Apr 2020 11:42:29 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/17/20 11:26 AM, Linus Torvalds wrote: > On Fri, Apr 17, 2020 at 8:16 AM Jens Axboe wrote: >> >> - Work restore poll cancelation fix > > That whole apoll thing is disgusting. > > I cannot convince myself it is right. How do you convince yourself? req->poll is used for pure poll requests, req->apoll is used for poll that is armed on behalf of a non-poll request. So the paths are actually pretty well defined, for both the submission side entry, and the completion side which is through the wakeup handlers. The handlers that deal with the "poll on behalf of another request" is pretty short and limited. Anything that uses "poll on behalf of others" is not going to be queued async, which is the overlap with io_wq_work in the io_kiocb structure. The only part we have to be a bit careful with there is for the assume contexts, like mm etc. One of the fixes in this pull request deals with that. -- Jens Axboe