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=-4.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 A379AC433E0 for ; Sat, 20 Mar 2021 18:21:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7C39D6186A for ; Sat, 20 Mar 2021 18:21:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230028AbhCTSVV (ORCPT ); Sat, 20 Mar 2021 14:21:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46346 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229805AbhCTSUt (ORCPT ); Sat, 20 Mar 2021 14:20:49 -0400 Received: from mail-qk1-x72a.google.com (mail-qk1-x72a.google.com [IPv6:2607:f8b0:4864:20::72a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9A760C061574 for ; Sat, 20 Mar 2021 11:20:48 -0700 (PDT) Received: by mail-qk1-x72a.google.com with SMTP id g15so6442617qkl.4 for ; Sat, 20 Mar 2021 11:20:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=qjtwcm8fTgfE4yO/PEWWKlgJq9PQJ431uqNdo6ZHTRY=; b=aZGqiNkBU3FtTfzXguJ9fM7L8HsQEHbXBrYDTTOBhAgcYWpmDKpuUDo7cu1Gbqgh7G FcXBdR53mDAQN/h32tYE/Rz+4atVPwNmiQIro/WjSVG+o+3n6IjAYFhUBUaXHy5neHtC y/n6XT5Cpm0m/obhRuZLVuHoYzSTXy6u3Tu6bhwSyKODrrwIApx6sPIMQ4xB9DI8qE+f RACbb/Ktf+M6dj9zT1VwcqY9b4h0cQpzwWRR84BNS814G2P5Khwv/glKsPLUfmd0o/LQ oPPRxm7HCuanYMA0eDvrxSxAYWeM/Le8Iql4GnTBiYj/hOxF5Nd/FUhtBYhnJWeJldLZ B7pQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=qjtwcm8fTgfE4yO/PEWWKlgJq9PQJ431uqNdo6ZHTRY=; b=nDW12ftJKid/hJdiTvOb6Lw3sXrO/rP6zctb6iHH0wvgfrRzmVH548AJmf3lZga05z CDlSzuWbwPwlx3PqxdCS8C/EJ+9m90B2XAxWOV3KNqRb5PYNqQ7em/ajp15CmtUqY4CQ eULYOVjEmeXDjpvfTUmXbbcIMUYZNNg5nFnTkj58jujP5MsPI6Npbu2jeUKzgXLFKV0W zkUDEpND/CyfsHdqGRDGtI0MYUZc7sSaNx0Lkp1/ZIUcQVmCGioV3lq+6B8ZzNvalhu6 kr+hKhABuU/nxtoj6VcfOY3XFfsF4sVNPP3onNyh8PUybyTsQXpopNozvZ4QEp9U6pCi emIQ== X-Gm-Message-State: AOAM531J9lsm3g3TXYtKYOuLJdV0aAozQeEelv3PHnaFojbLumfskcMn +TJMB3n017rl/Uch2WHzKtA= X-Google-Smtp-Source: ABdhPJx7mQ6YjoT/7LdEReVD4sPb2YAM1LxG7u47Y/V+0uV3uircrrsB9wj+nC7+a8kuY0RJIpW2pg== X-Received: by 2002:a37:408:: with SMTP id 8mr3963942qke.406.1616264447660; Sat, 20 Mar 2021 11:20:47 -0700 (PDT) Received: from localhost (2603-7000-9602-8233-06d4-c4ff-fe48-9d05.res6.spectrum.com. [2603:7000:9602:8233:6d4:c4ff:fe48:9d05]) by smtp.gmail.com with ESMTPSA id y8sm6305723qtn.68.2021.03.20.11.20.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 20 Mar 2021 11:20:47 -0700 (PDT) Sender: Tejun Heo Date: Sat, 20 Mar 2021 14:20:46 -0400 From: Tejun Heo To: Wang Qing Cc: Lai Jiangshan , Andrew Morton , "Guilherme G. Piccoli" , Andrey Ignatov , Vlastimil Babka , Petr Mladek , Santosh Sivaraj , linux-kernel@vger.kernel.org Subject: Re: [PATCH V2] workqueue: watchdog: update wq_watchdog_touched for unbound lockup checking Message-ID: References: <1616140838-24222-1-git-send-email-wangqing@vivo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1616140838-24222-1-git-send-email-wangqing@vivo.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 19, 2021 at 04:00:36PM +0800, Wang Qing wrote: > When touch_softlockup_watchdog() is called, only wq_watchdog_touched_cpu > updated, while the unbound worker_pool running on its core uses > wq_watchdog_touched to determine whether locked up. This may be mischecked. Can you please elaborate here, preferably with a concrete scenario where the new code is better? Thanks. -- tejun