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=-5.9 required=3.0 tests=BAYES_00, 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 0D531C47082 for ; Thu, 3 Jun 2021 10:50:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E923E613D2 for ; Thu, 3 Jun 2021 10:50:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229864AbhFCKwa (ORCPT ); Thu, 3 Jun 2021 06:52:30 -0400 Received: from foss.arm.com ([217.140.110.172]:37990 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229817AbhFCKw3 (ORCPT ); Thu, 3 Jun 2021 06:52:29 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7C0431063; Thu, 3 Jun 2021 03:50:44 -0700 (PDT) Received: from [192.168.178.6] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 0F8FC3F774; Thu, 3 Jun 2021 03:50:41 -0700 (PDT) Subject: Re: [sched/pelt] e906550aca: WARNING:at_kernel/sched/fair.c:#update_blocked_averages To: kernel test robot , Vincent Guittot Cc: 0day robot , LKML , lkp@lists.01.org, ltp@lists.linux.it, mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, odin@uged.al, aubrey.li@linux.intel.com, yu.c.chen@intel.com References: <20210602064526.GB9872@xsang-OptiPlex-9020> From: Dietmar Eggemann Message-ID: <56316b95-3ec5-74e6-a4f7-d91aea022abe@arm.com> Date: Thu, 3 Jun 2021 12:50:36 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: <20210602064526.GB9872@xsang-OptiPlex-9020> Content-Type: text/plain; charset=windows-1252 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/06/2021 08:45, kernel test robot wrote: [...] > kern :warn : [ 40.989618] WARNING: CPU: 2 PID: 253 at kernel/sched/fair.c:8029 update_blocked_averages (kbuild/src/consumer/kernel/sched/fair.c:8029 kbuild/src/consumer/kernel/sched/fair.c:8065 kbuild/src/consumer/kernel/sched/fair.c:8152) Hit something like this on my Ubuntu i7-7567U as well. With more debugging: [ 7.388006] WARNING: CPU: 1 PID: 926 at kernel/sched/fair.c:8029 update_blocked_averages+0x30d/0x7e0 ... [ 7.388167] path=/autogroup-2 load_avg=1 util_avg=0 runnable_avg=1 IMHO, this is because this patch needs: (1) sched/pelt: ensure that *_sum is always synced with *_avg (2021-06-03 Vincent Guittot) https://lkml.kernel.org/r/20210601085832.12626-1-vincent.guittot@linaro.org (2) sched/fair: Keep load_avg and load_sum synced (2021-06-03 Vincent Guittot) tip/sched/urgent 7c7ad626d9a0 Using both patches underneath makes this warning go away.