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 E3F45C433DF for ; Tue, 11 Aug 2020 14:12:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B5CA820866 for ; Tue, 11 Aug 2020 14:12:28 +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="sY4W60GQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728491AbgHKOM2 (ORCPT ); Tue, 11 Aug 2020 10:12:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48150 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728516AbgHKOM2 (ORCPT ); Tue, 11 Aug 2020 10:12:28 -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 0CBA8C061787 for ; Tue, 11 Aug 2020 07:12:28 -0700 (PDT) Received: by mail-pj1-x1044.google.com with SMTP id i92so1574511pje.0 for ; Tue, 11 Aug 2020 07:12:28 -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=OOlZ+ATYXp0embk0Xt0D7/zojHK+eypmET3/SJQqP3Q=; b=sY4W60GQgss5PGDlEi0PP5sQjeZSO3iLmw8XGvV1kJUYz2oJe5Hz5Yr2NHhY9Nzgqv OljIi/qatKO7Wwa83fSKC+uSZXzkEHHyA/qjY/IHRInj2tQZVvysxtIbO1ohvpR3UB8C 6xM3TiQHp1rI55Kw5YfEWrXoDgrODPfZi6VjT9qU3+ytjKqqPbJooOGYiNzb/PeKTmZu NPl1rbFBj1UbDJZUdJrRObyKeWJbHVpztJimro6g2KzDOzTPC5tMhtieN6U7a17ZxEkF I10ceLErgH0vqWjlIzV+gzRKn9LgQTSn3sSYhPucrkn+sBMtGeB+zTq5V3QEvpG2LcyH Y9Qw== 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=OOlZ+ATYXp0embk0Xt0D7/zojHK+eypmET3/SJQqP3Q=; b=Sbgb/UH4HCyWvZfVtk4btiXcYa0LTv0z1lPeuBz75csoIMBrP6W/XQrt8HzwYQjVXU dz4bi6SxMkZdMhAdSzSF+AU117Iu6+p35Gu67wHwKCWxHV4HgAWce+oxHaxnrqAka3Dm 8epBc4w3fABiM2ltSrN3wmCq7ZUkj0Ggqg0ilBCpT92dOFU/S0585AdZiXYl4tBX56Sx uoLsIJqmiAnIy0nGgcXRqKQX53C/Ts5lsUru49ejTao0NrIN4vjH5L+qL3ErM9vLm1mm AnTVB3RZXmCrxiCXBSrfKq8p80BYdXdlUd4O/jnYhpPHav7QyuywllIyD6fX8QDxpI2O ALCA== X-Gm-Message-State: AOAM532g5by70dE62Nl2kBJHLIIfryyNNan+Bgmx0gTGp+whZk+gvvl1 No+BtojdQDBYMYZ2MsRywuXzmQ== X-Google-Smtp-Source: ABdhPJxxjtY+Kp4EiPt+PSXYh8asEW33CoEBH2K4kvELJ2y3apqudwX2y0SeNMSQkeA1CMpoyt7T8A== X-Received: by 2002:a17:90b:784:: with SMTP id l4mr1191498pjz.96.1597155147453; Tue, 11 Aug 2020 07:12:27 -0700 (PDT) Received: from [192.168.1.182] ([66.219.217.173]) by smtp.gmail.com with ESMTPSA id lk16sm2860632pjb.13.2020.08.11.07.12.26 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 11 Aug 2020 07:12:26 -0700 (PDT) Subject: Re: [PATCH 2/2] io_uring: use TWA_SIGNAL for task_work if the task isn't running To: Oleg Nesterov Cc: Peter Zijlstra , Jann Horn , io-uring , stable , Josef References: <1629f8a9-cee0-75f1-810a-af32968c4055@kernel.dk> <20200811064516.GA21797@redhat.com> <20200811065659.GQ3982@worktop.programming.kicks-ass.net> <20200811071401.GB21797@redhat.com> <20200811074538.GS3982@worktop.programming.kicks-ass.net> <20200811081033.GD21797@redhat.com> <20200811140525.GE21797@redhat.com> From: Jens Axboe Message-ID: <0790382f-46d0-0520-443a-cbedb37900f8@kernel.dk> Date: Tue, 11 Aug 2020 08:12:25 -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: <20200811140525.GE21797@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: io-uring-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 8/11/20 8:05 AM, Oleg Nesterov wrote: > On 08/11, Jens Axboe wrote: >> >> I'd really like to get this done at the same time as the io_uring >> change. Are you open to doing the READ_ONCE() based JOBCTL_TASK_WORK >> addition for 5.9? > > Yes, the patch looks fine to me. In fact I was going to add this > optimization from the very beginning, but then decided to make that > patch as simple as possible. OK great, I'll send that out separately. > And in any case I personally like this change much more than 1/2 + > 2/2 which I honestly don't understand ;) Yes, in retrospect, me too :-) -- Jens Axboe