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=-5.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, 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 515EBC433FE for ; Sun, 6 Dec 2020 01:19:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2385122D08 for ; Sun, 6 Dec 2020 01:19:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726419AbgLFBS7 (ORCPT ); Sat, 5 Dec 2020 20:18:59 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:26600 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725920AbgLFBS6 (ORCPT ); Sat, 5 Dec 2020 20:18:58 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1607217452; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3oBqs4Sgc/+zmOSMdRU+JqaQfvk0jsHxfKMItF61nLE=; b=GaUDoh/xT6x2dw0AlwqpPV1sah6kWMsNMnTTwh6LOV7MhBPoOwbQeYHZdfqMGTa0sR6i5Q E07J1SgT7jbC6HAzu8Ww43YtWbGUvgM7T2PBol7rD1BLdm3Jg1fERTSmQXFAHV9DTQdJ6F YLylRbp78BKqP4Xsi51axNhRHgjcPZ4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-125-ROCizOzXNCOZBB4dPv2IRg-1; Sat, 05 Dec 2020 20:17:30 -0500 X-MC-Unique: ROCizOzXNCOZBB4dPv2IRg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 436691005504; Sun, 6 Dec 2020 01:17:28 +0000 (UTC) Received: from ovpn-66-5.rdu2.redhat.com (unknown [10.10.67.5]) by smtp.corp.redhat.com (Postfix) with ESMTP id B4E4D5C1A1; Sun, 6 Dec 2020 01:17:18 +0000 (UTC) Message-ID: <665aeda20e06c7f21224a48a42044112d59b3754.camel@redhat.com> Subject: Re: [PATCH v4 11/19] sched/core: Make migrate disable and CPU hotplug cooperative From: Qian Cai To: Valentin Schneider Cc: Peter Zijlstra , tglx@linutronix.de, mingo@kernel.org, linux-kernel@vger.kernel.org, bigeasy@linutronix.de, qais.yousef@arm.com, swood@redhat.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vincent.donnefort@arm.com, tj@kernel.org, ouwen210@hotmail.com Date: Sat, 05 Dec 2020 20:17:18 -0500 In-Reply-To: References: <20201023101158.088940906@infradead.org> <20201023102347.067278757@infradead.org> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2020-12-05 at 18:37 +0000, Valentin Schneider wrote: > From there I see: > > [20798.166987][ T650] CPU127 nr_running=2 > [20798.171185][ T650] p=migration/127 > [20798.175161][ T650] p=kworker/127:1 > > so this might be another workqueue hurdle. This should be prevented by: > > 06249738a41a ("workqueue: Manually break affinity on hotplug") Well, since it was reproduced on the latest linux-next which has already included the commit. > Note that much earlier in your log, you have a softlockup on CPU127: > > [ 74.278367][ C127] watchdog: BUG: soft lockup - CPU#127 stuck for 23s! > [swapper/0:1] That's something separate. It was there all the time. https://lore.kernel.org/linux-acpi/20200929183444.25079-1-cai@redhat.com/