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=-5.5 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, 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 6A0B8C433DF for ; Fri, 16 Oct 2020 14:53:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 13F7120874 for ; Fri, 16 Oct 2020 14:53:59 +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="rvUHYiv6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2409436AbgJPOx6 (ORCPT ); Fri, 16 Oct 2020 10:53:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58132 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2394947AbgJPOx5 (ORCPT ); Fri, 16 Oct 2020 10:53:57 -0400 Received: from mail-pg1-x541.google.com (mail-pg1-x541.google.com [IPv6:2607:f8b0:4864:20::541]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D964BC0613D3 for ; Fri, 16 Oct 2020 07:53:55 -0700 (PDT) Received: by mail-pg1-x541.google.com with SMTP id q21so1579562pgi.13 for ; Fri, 16 Oct 2020 07:53:55 -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=7wrAFrQUbhjohmG+yzeVkhlwYfh81dSt3oQQlEyyNKQ=; b=rvUHYiv61e9UOpqMZ+1aLFH3V8k1Sy2d+UAevkQKgGSi8I5uAdCcSSkknLrG3NchXK 7jeWq31V/oLD1kCucsslIcUcfTG/EvAfn2qCF4pZ8eXeUrlOsf9mcSf++TVN1SJvyEbS kaJWz/WkpsWZEl7yd3MOXklPQQFwoWMSP6KgVq7is1KZAzW4hs8H/5fuG0yApyLnJs06 893TadG7sR7BazPsL2Q7qNQlYQz5F6Ov03xqJ7ZiGESruEvc95o7UEic9rtDlM4O27+t tqDLlqM8BKLDVzX0gOy6RPCp9a7Q9cLjFdLsyxJ9wyQgnJJKnI0Co9zbTp15Msi+eghq Rdmg== 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=7wrAFrQUbhjohmG+yzeVkhlwYfh81dSt3oQQlEyyNKQ=; b=lyNy5Aixr+fX18JlQTYXwRDQLuxDpzlL9Y6cD0KCCvrlAOe8GHx/JvhSraGgNQNw1b TxS+XyYhqBmZNV9KazWb9V7Onwbupd4fUmaWnMuOmQRm2K3bQd9FGaWFH1sjdGWkZzwD Iz1lm7cBRsYspTnsCszKzJr2c5JujQrCcCptIeFSc+SIP9CLD+9JAVCJf2eI9gtXchv/ NgU1XX9rasPv27EzrHk5APwHvoerjbEH0yB/sJg5A6bfkiNJVMzuIEU2k4qIMElRPo0E 3hHP8UeDfjFBKbZDQ0J75uGqpZ+mx30L+m/iN1594LcPxuQ2HVwmJS+fFtBDu/XyIV1h YpCA== X-Gm-Message-State: AOAM532a5mlZ8KMjI8wyFfqSkH1aRFOi83dOgPYJBFvRUZijuFI4peyc YKQ0kS6wcMGzF/ggt61e3C4ttQ== X-Google-Smtp-Source: ABdhPJwQZhhvkLFb1LbTZK7fHEb1X6uNP4Dy3qqVx1CPMR97ZjGa84MNNPd0X/7+SLmhIO9usrv4cw== X-Received: by 2002:a63:e705:: with SMTP id b5mr3374044pgi.230.1602860035351; Fri, 16 Oct 2020 07:53:55 -0700 (PDT) Received: from [192.168.1.134] ([66.219.217.173]) by smtp.gmail.com with ESMTPSA id 132sm3094943pfu.52.2020.10.16.07.53.54 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 16 Oct 2020 07:53:54 -0700 (PDT) Subject: Re: [PATCH 5/5] task_work: use TIF_NOTIFY_SIGNAL if available To: Oleg Nesterov , Thomas Gleixner Cc: linux-kernel@vger.kernel.org, io-uring@vger.kernel.org, peterz@infradead.org, Roman Gershman References: <20201015131701.511523-1-axboe@kernel.dk> <20201015131701.511523-6-axboe@kernel.dk> <20201015154953.GM24156@redhat.com> <87a6wmv93v.fsf@nanos.tec.linutronix.de> <871rhyv7a8.fsf@nanos.tec.linutronix.de> <87a6wmtfvb.fsf@nanos.tec.linutronix.de> <20201016145138.GB21989@redhat.com> From: Jens Axboe Message-ID: <1a89eacd-830e-7310-0e56-9b4b389cdc5d@kernel.dk> Date: Fri, 16 Oct 2020 08:53:53 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20201016145138.GB21989@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/16/20 8:51 AM, Oleg Nesterov wrote: > On 10/16, Thomas Gleixner wrote: >> >> With moving the handling into get_signal() you don't need more changes >> to arch/* than adding the TIF bit, right? > > we still need to do something like > > - if (thread_flags & _TIF_SIGPENDING) > + if (thread_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) > do_signal(...); > > and add _TIF_NOTIFY_SIGNAL to the WORK-PENDING mask in arch/* code. Yes, but it becomes really minimal at that point, and just that. There's no touching any of the arch do_signal() code. Just finished the update of the branch to this model, and it does simplify things quite a bit! Most arch patches are now exactly just what you write above, no more. -- Jens Axboe