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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 47A10C433EF for ; Mon, 11 Jul 2022 07:43:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230141AbiGKHnf (ORCPT ); Mon, 11 Jul 2022 03:43:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58446 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229668AbiGKHnc (ORCPT ); Mon, 11 Jul 2022 03:43:32 -0400 Received: from mail-lj1-x22c.google.com (mail-lj1-x22c.google.com [IPv6:2a00:1450:4864:20::22c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E1D116568; Mon, 11 Jul 2022 00:43:29 -0700 (PDT) Received: by mail-lj1-x22c.google.com with SMTP id o12so2608935ljc.3; Mon, 11 Jul 2022 00:43:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=6+Eje+BI4mgYWYNE16gkK8LI+X4SswO3LLw9Mljelro=; b=jcaIQZW81P74s1CpNAYO8N8l0GZfj7ayncDoX4MF8kXAAWbl4HvPSxXIfhr6A+3/nx O2ZTotadCJTDen2eFsibLo3TqpPkBw+NUjgBTB7Af8Mw7S5UftVGJMQSon7jl6ecbkgZ EQSw+JHmykzIY8For3YASqO7XzibR5TeF/gb8MClV4iPy86bXdZ9BFx+PW/7Z9s42sqT UZWwv9GJ8JC6+k1rOzTvSKIo2c52vAxnyYaRDOEmm+T7z48Lu9aSKMxmcz+TioEzGAN7 UghtWSk4Ct41GfxY16+1v6eaTagFAp/21tzaJUNRtO4it+xNy+BXVBlybJynr583Msin pw4w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=6+Eje+BI4mgYWYNE16gkK8LI+X4SswO3LLw9Mljelro=; b=c9mx3EgKZYvSVlSRIondbxnBTLWzH0gRlp9W12cCwVyOwQsW3BmIb+mlRPscujToyw VgOWzQ2OQoJORBT3JFuVrjBjt3AK1OHcZ1EZWTrKYfcLA2Crxu87ZOhqm1ZEC8rjHRKY 2bTHHrkibChZsefr63sq5C4E04raXfz54L0u4yky58S7ShnCl8wec1rndk+X84QGimDD ip94TNBVUWpUMfcE9im/aXKLM8HEkJ8onu/laCPi+jIpk3JIIFIC+rwBUie2VSgtPyG5 Mw2ecPJKFdXPz8NB7M6SiK+6PR8FpLcetQer/XNhBmATqevX97flQsGh228dDM4aHgmG XHHA== X-Gm-Message-State: AJIora+BwqHYyKVhlKzCli7XQT46LNKebWAX/fd6K8OE4NEcQqUAHcbU E1omtcw9u2kc9IrWNrfmHx4BZQ4D9vw46XTatpQ= X-Google-Smtp-Source: AGRyM1sWvpjgSJFW19NE3gcXq3cbOwxFZbvPtLSl2rdJY2M8qgy5upBrRLJTDyNwcyAnlw4QRDKk67ablDHOMGZeV7c= X-Received: by 2002:a2e:bf20:0:b0:25a:45a6:7587 with SMTP id c32-20020a2ebf20000000b0025a45a67587mr9504164ljr.377.1657525408206; Mon, 11 Jul 2022 00:43:28 -0700 (PDT) MIME-Version: 1.0 References: <20220705123705.764-1-xuewen.yan@unisoc.com> <9ade9d43-3ed1-1239-f26e-73145856275a@arm.com> In-Reply-To: <9ade9d43-3ed1-1239-f26e-73145856275a@arm.com> From: Xuewen Yan Date: Mon, 11 Jul 2022 15:43:17 +0800 Message-ID: Subject: Re: [PATCH] sched/schedutil: Fix deadlock between cpuset and cpu hotplug when using schedutil To: Lukasz Luba Cc: Xuewen Yan , rafael@kernel.org, viresh.kumar@linaro.org, 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, linux-kernel@vger.kernel.org, ke.wang@unisoc.com, xuewyan@foxmail.com, linux-pm@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 11, 2022 at 3:32 PM Lukasz Luba wrote: > > Hi Xuewen, > > On 7/11/22 08:21, Xuewen Yan wrote: > > Hi all > > > > This deadlock is inevitable, any comment? > > Could you tell me how to reproduce this? > Is there a need of special cgroup setup? This deadlock occurs when we run the monkey test on an Android phone, at the same time, randomly put online or offline a cpu core. Indeed the thread-A which get the cgroup_threadgroup_rwsem and waiting for the cpu_hotplug_lock is the thread whose name is "OomAdjuster" in android. And I see the cpu_hotplug_lock is added by the patch: https://lore.kernel.org/all/20220121101210.84926-1-zhangqiao22@huawei.com/ Thanks! > > Regards, > Lukasz