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=-5.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 68BF7C432C0 for ; Wed, 27 Nov 2019 12:10:35 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 369F22071E for ; Wed, 27 Nov 2019 12:10:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="hB9bU/6y" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 369F22071E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=XSSdNe9c9AgTMTspfNvg5phH3Jg+6Cdf8BynZNq2Esk=; b=hB9bU/6yW306ZP KA2y3PqIvBMFSJhyBMiglf5E+43URpO8LQtFJJgAhl8l36WB0vvHwH3ZK2AFiQxE7E2TgcDfMVENz EDcH/1WTQ2Rzm4yvmCKPGO6JIu3VMdSjeiU+mIEUsdGNFIRuEOiRe8Mw4dEYmpmRQ/x5uem39dWdQ E2kqyBGvSI+LVdNn+kzzDMIzTXt0iwVsa+C0Vy+bp/MQUCC0HgWrgkr+BtYv1/uT0q9dr5a5elneG yGxVnjwyMCvv2ZCS0LNQ6uIQjATni2W2kg5MG/JRs2GuJp14gix6iQ46o+VmNpy1tApnRo0zp4lrb zpgbdPSieGGX745OoZcg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iZw9S-0002MQ-7H; Wed, 27 Nov 2019 12:10:34 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iZw9O-0002LU-3B for linux-arm-kernel@lists.infradead.org; Wed, 27 Nov 2019 12:10:31 +0000 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 C48DF30E; Wed, 27 Nov 2019 04:10:28 -0800 (PST) Received: from bogus (e107155-lin.cambridge.arm.com [10.1.196.42]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 54C553F6C4; Wed, 27 Nov 2019 04:10:27 -0800 (PST) Date: Wed, 27 Nov 2019 12:10:25 +0000 From: Sudeep Holla To: Viresh Kumar Subject: Re: [PATCH] cpufreq: vexpress-spc: Fix wrong alternation of policy->related_cpus during CPU hp Message-ID: <20191127121025.GD29301@bogus> References: <20191127114801.23837-1-dietmar.eggemann@arm.com> <20191127120744.iivgw25nixovfj7i@vireshk-i7> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20191127120744.iivgw25nixovfj7i@vireshk-i7> User-Agent: Mutt/1.9.4 (2018-02-28) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191127_041030_189076_7075C643 X-CRM114-Status: GOOD ( 19.35 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Lorenzo Pieralisi , linux-pm@vger.kernel.org, "Rafael J . Wysocki" , Liviu Dudau , linux-kernel@vger.kernel.org, Morten Rasmussen , linux-arm-kernel@lists.infradead.org, Sudeep Holla , Dietmar Eggemann , Lukasz Luba Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Nov 27, 2019 at 05:37:44PM +0530, Viresh Kumar wrote: > On 27-11-19, 12:48, Dietmar Eggemann wrote: > > Since commit ca74b316df96 ("arm: Use common cpu_topology structure and > > functions.") the core cpumask has to be modified during cpu hotplug > > operations. > > > > ("arm: Fix topology setup in case of CPU hotplug for CONFIG_SCHED_MC") > > [1] fixed that but revealed another issue on TC2, i.e in its cpufreq > > driver. > > > > During CPU hp stress operations on multiple CPUs, policy->related_cpus > > can be altered. This is wrong since this cpumask should contain the > > online and offline CPUs. > > > > The WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)) in > > cpufreq_online() triggers in this case. > > > > The core cpumask can't be used to set the policy->cpus in > > ve_spc_cpufreq_init() anymore in case it is called via > > cpuhp_cpufreq_online()->cpufreq_online()->cpufreq_driver->init(). > > > > An empty online() callback can be used to avoid that the init() > > driver function is called during CPU hotplug in so that > > policy->related_cpus will not be changed. > > > > Implementing an online() also requires an offline() callback. > > > > Tested on TC2 with CPU hp stress test (CPU hp from multiple CPUs at > > the same time). > > > > [1] > > https://lore.kernel.org/r/20191127103353.12417-1-dietmar.eggemann@arm.com > > > > Signed-off-by: Dietmar Eggemann > > Wanna provide any fixes tag ? > > > --- > > drivers/cpufreq/vexpress-spc-cpufreq.c | 12 ++++++++++++ > > 1 file changed, 12 insertions(+) > > This is 5.5 material or 5.6 ? > v5.5 for sure, broken even on v5.4 but unless someone really cares for stable on TC2, I am happy to skip it. -- Regards, Sudeep _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel