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=-5.3 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 B980FC433E0 for ; Mon, 25 Jan 2021 04:29:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 82BE322C7B for ; Mon, 25 Jan 2021 04:29:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726934AbhAYE2w (ORCPT ); Sun, 24 Jan 2021 23:28:52 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56820 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726760AbhAYE2p (ORCPT ); Sun, 24 Jan 2021 23:28:45 -0500 Received: from mail-pj1-x102a.google.com (mail-pj1-x102a.google.com [IPv6:2607:f8b0:4864:20::102a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B32DC061573 for ; Sun, 24 Jan 2021 20:28:05 -0800 (PST) Received: by mail-pj1-x102a.google.com with SMTP id e9so383587pjj.0 for ; Sun, 24 Jan 2021 20:28:05 -0800 (PST) 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=6dXiISuywEBuazI4xj4yFxY1nkp6ZflUiyorvnDifvs=; b=Pq81h34KvrPTQiyWomze+Gw0KOD9of/oGveHh8B5C5f5Sw4seL+lndqGq/fAjIrD+J 05Cx+85/WkzFyXxhTM5yroL3dsKGbDYim/4ymqHmdb7IR3xzTBf3w2oGIBTQFsDm1st3 hHEDn3TsvNVeMQ3/2qwteLe7YDeG/gE+x/cn6aO3UAHsIa7MF1h9DPFeoaf2sCEvujnO 6JaptvWLA7TZRWpvpkGFFG4C6yh9Hy5FZUS1NW8LBIQbROK31BVgszsAhQZK9qtmOJzX WqSFtCAH8vAZvmoCr00LoAGUqYUtjbSl418ug6Cav3y2Loqs5rsA09FKY4BJumwuwhQa d0VA== 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=6dXiISuywEBuazI4xj4yFxY1nkp6ZflUiyorvnDifvs=; b=YK+fJMrzBcUPQW9C6G+9S9V54snXqfHh7ZOPCDoxI+WjvMmQGf8A3cKsh9I8tSQN/i xDcOKbZxdNaHTx81/U7+5twlP6GllYSlRgTiuVK0wUlxgHdtdiMZiMa+/SaP9ZFpzwte V7NFz+7bxIMhaakwckrKpCiD85CqUbCqZ2ImSezZVrN0pCB7n0q2ql4URM0bvg6R3oP+ uHeo1NUOZEsQhmsEZT6P8AIlcQ0Wle6auZE1i4MAIrUSzUu0sacCovlTzOoKIV0N2vHh 8vFVL/8T1FJbtH+/pvrN8AsEo2rBH06Hi+mu07TIjjlYDhmvbnLZufR9n2X/cp/UPaoC Nz9g== X-Gm-Message-State: AOAM533+mDp7WM65AhiG6mf9cJYfHEvSFkL/UVPHQVofG1MP7SnLrVgo ocXyfrUcfDvxhZ7PXQnZIXgNRg== X-Google-Smtp-Source: ABdhPJw/2/1B5rytSzbIS7zdfgAkoF4oaB/9PLp8Tj4sfje42S00tsY6WtySESAMMoXHwKIe7NHOoQ== X-Received: by 2002:a17:902:ed88:b029:de:86f9:3e09 with SMTP id e8-20020a170902ed88b02900de86f93e09mr17759813plj.38.1611548885148; Sun, 24 Jan 2021 20:28:05 -0800 (PST) Received: from [192.168.4.41] (cpe-72-132-29-68.dc.res.rr.com. [72.132.29.68]) by smtp.gmail.com with ESMTPSA id gv22sm16102738pjb.56.2021.01.24.20.28.03 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 24 Jan 2021 20:28:04 -0800 (PST) Subject: Re: [PATCH v3 0/3] blk-mq: Don't complete in IRQ, use llist_head To: Sebastian Andrzej Siewior , linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Thomas Gleixner , Peter Zijlstra , Ingo Molnar References: <20210123201027.3262800-1-bigeasy@linutronix.de> From: Jens Axboe Message-ID: <4e703284-2f75-6030-f697-aa2d362c3949@kernel.dk> Date: Sun, 24 Jan 2021 21:27:54 -0700 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: <20210123201027.3262800-1-bigeasy@linutronix.de> 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 1/23/21 1:10 PM, Sebastian Andrzej Siewior wrote: > Patch 2+3 were applied and then dropped by Jens due to a NOHZ+softirq > related warning [0]. Turns out a successful wakeup via > set_nr_if_polling() will not process any softirqs and the CPU may go > back to idle. This is addressed by patch #1. > > smpcfd_dying_cpu() will also invoke SMP-functions calls via > flush_smp_call_function_queue() but the block layer shouldn't queue > anything because the CPU isn't online anymore. > The two caller of flush_smp_call_function_from_idle() look fine with > opening interrupts from within do_softirq(). > > [0] https://lkml.kernel.org/r/1ee4b31b-350e-a9f5-4349-cfb34b89829a@kernel.dk I can queue up the block side once the IPI fix is in some stable branch that I can pull in. -- Jens Axboe