From nobody Thu May 7 19:50:13 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B7ACDC433F5 for ; Thu, 19 May 2022 16:12:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241850AbiESQMD (ORCPT ); Thu, 19 May 2022 12:12:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33744 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241083AbiESQL6 (ORCPT ); Thu, 19 May 2022 12:11:58 -0400 Received: from mail-io1-xd29.google.com (mail-io1-xd29.google.com [IPv6:2607:f8b0:4864:20::d29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EDCABAFB1D for ; Thu, 19 May 2022 09:11:55 -0700 (PDT) Received: by mail-io1-xd29.google.com with SMTP id p74so2639117iod.8 for ; Thu, 19 May 2022 09:11:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=Z9JuQdbnyix/Cw2s/uS/02pnjmPQ42SuLyLty1YjLH8=; b=Aa841zG4DYWnqVq5zJHLVf9PcPp8NoKgOR8vVxN68li1B198TGkNUKfJDQDPqq3PKF 9auRyny2CyM0KAeiww1FQQGBl7uh04eAyUO8LDra0c4R69+3DCcpNw9vcyxjrkXwh6FH 3u8GKzljCq+yRdESJki4sDv1msi3XokEKEgQx0y4B2KMkDmXuAEqAePA0lfp4I7BJgKF ch/EaBfy8ujyLEOOK7eXG6grUpIGZ5Dfuak53cjVJ4w9XaXpRWDTCyxQCYyK+MbwBYUo L9U4QhjPxExwRhkXneBV5PeyVWZWFwR0AwdbQu19vjfm/V3J4cdxg4jMA7jXNsGQuMyN 1OXA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=Z9JuQdbnyix/Cw2s/uS/02pnjmPQ42SuLyLty1YjLH8=; b=rPcdPdXRP/TKKmN4gdGolnREHYuZ6VuZ4csIzb5t0yXXlel6ZN+PGUTBj4IAQdBwXb 9op4vQJPi6Fg3JXLfgjQjmLUdGGH5KXjU6A1gsqcxLdmuVMzYVUqxQ17aHvZQFileRqg eLmYrSzWecg2bGJFF0bC9hnGKWKl7Thh9QJzAZR+vJ0S0MatLMFZn/QjrlDqzHsOGvOE V20THEZk2Aexm/6THgo8crLP3ZSleOOPv+7+k9w/p+IcAKMplFzMqEF4hOmYMvUeZtfW ZqVqRmipHMgibkYVI/OJQPgl1/4g00eIb0Asl2SIZRDq4KSzeKnQH1rDzhX4MSfO3PV4 nT4g== X-Gm-Message-State: AOAM530wyUul0p51wsVCgFZdHRsIK1rt7VFha9AZk32ew83YvvitoHed DStX2miTQtiCdzNDEmmnBAQ= X-Google-Smtp-Source: ABdhPJwWqjwfIJd8j6I/+9ff9Vz6fKNxGW4RFWDoJajx/RLpilS9EvjwcwZailmSGC+66ruuR5yL1g== X-Received: by 2002:a05:6602:1501:b0:65a:c412:2eeb with SMTP id g1-20020a056602150100b0065ac4122eebmr2811315iow.29.1652976715359; Thu, 19 May 2022 09:11:55 -0700 (PDT) Received: from localhost.localdomain (ec2-13-59-0-164.us-east-2.compute.amazonaws.com. [13.59.0.164]) by smtp.gmail.com with ESMTPSA id g8-20020a05660203c800b0065a47e16f64sm823862iov.54.2022.05.19.09.11.49 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Thu, 19 May 2022 09:11:55 -0700 (PDT) From: Schspa Shi To: mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com Cc: linux-kernel@vger.kernel.org, Schspa Shi Subject: [PATCH] sched: Dump stacktrace when some task failed to stop Date: Fri, 20 May 2022 00:11:25 +0800 Message-Id: <20220519161125.41144-1-schspa@gmail.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Some processes may not be stopped, such as workqueue workers. Add this dump_stack to easily figure out which process caused the problems. Before this change: <4>[ 517.545889] ------------[ cut here ]------------ <4>[ 517.545901] Dying CPU not properly vacated! <4>[ 517.546366] ---[ end trace 0000000000000002 ]--- <4>[ 518.546831] CPU6 enqueued tasks (2 total): <4>[ 518.546855] pid: 49, name: migration/6 <4>[ 518.547010] pid: 6231, name: kworker/6:0 Signed-off-by: Schspa Shi --- kernel/sched/core.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 53596842f0d8..de6b5320e4d7 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -9416,7 +9416,14 @@ static void dump_rq_tasks(struct rq *rq, const char = *loglvl) continue; =20 printk("%s\tpid: %d, name: %s\n", loglvl, p->pid, p->comm); + if (p !=3D current) + sched_show_task(p); } + /* + * We need the stack of each cpu to analyze who is blocking the + * current cpu scheduling + */ + trigger_all_cpu_backtrace(); } =20 int sched_cpu_dying(unsigned int cpu) --=20 2.24.3 (Apple Git-128)