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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 99709ECE597 for ; Thu, 17 Oct 2019 17:15:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 77F902089C for ; Thu, 17 Oct 2019 17:15:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2440640AbfJQRPB (ORCPT ); Thu, 17 Oct 2019 13:15:01 -0400 Received: from [217.140.110.172] ([217.140.110.172]:41934 "EHLO foss.arm.com" rhost-flags-FAIL-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1728639AbfJQRO7 (ORCPT ); Thu, 17 Oct 2019 13:14:59 -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 8E266328; Thu, 17 Oct 2019 10:14:38 -0700 (PDT) Received: from bogus (e107155-lin.cambridge.arm.com [10.1.196.42]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8ADDE3F718; Thu, 17 Oct 2019 10:14:37 -0700 (PDT) Date: Thu, 17 Oct 2019 18:14:32 +0100 From: Sudeep Holla To: "Rafael J. Wysocki" Cc: Linux PM , Linux ACPI , LKML , Viresh Kumar , Dmitry Osipenko , Sudeep Holla Subject: Re: [RFT][PATCH 0/3] cpufreq / PM: QoS: Introduce frequency QoS and use it in cpufreq Message-ID: <20191017171432.GA32485@bogus> References: <2811202.iOFZ6YHztY@kreacher> <20191016142343.GB5330@bogus> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191016142343.GB5330@bogus> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 16, 2019 at 03:23:43PM +0100, Sudeep Holla wrote: > On Wed, Oct 16, 2019 at 12:37:58PM +0200, Rafael J. Wysocki wrote: > > Hi All, > > > > The motivation for this series is to address the problem discussed here: > > > > https://lore.kernel.org/linux-pm/5ad2624194baa2f53acc1f1e627eb7684c577a19.1562210705.git.viresh.kumar@linaro.org/T/#md2d89e95906b8c91c15f582146173dce2e86e99f > > > > and also reported here: > > > > https://lore.kernel.org/linux-pm/20191015155735.GA29105@bogus/ > > > > Plus, generally speaking, using the policy CPU as a proxy for the policy > > with respect to PM QoS does not feel particularly straightforward to me > > and adds extra complexity. > > > > Anyway, the first patch adds frequency QoS that is based on "raw" PM QoS (kind > > of in analogy with device PM QoS) and is just about min and max frequency > > requests (no direct relationship to devices). > > > > The second patch switches over cpufreq and its users to the new frequency QoS. > > [The Fixes: tag has been tentatively added to it.] > > > > The third one removes frequency request types from device PM QoS. > > > > Unfortunately, the patches are rather big, but also they are quite > > straightforward. > > > > I didn't have the time to test this series, so giving it a go would be much > > appreciated. > > Thanks for the spinning these patches so quickly. > For the record, I thought of providing the crash that this series fixes. After applying [1] which fixes the boot issue I was seeing on TC2, I started seeing the below crash, which this series fixes. FWIW, Tested-by: Sudeep Holla -- Unable to handle kernel paging request at virtual address 31b2c303 pgd = 772b96e1 [31b2c303] *pgd=a4050003, *pmd=00000000 Internal error: Oops: 206 [#1] SMP THUMB2 Modules linked in: CPU: 1 PID: 518 Comm: bash Not tainted 5.4.0-rc3-00062-g6e3a7fd7a87e-dirty #123 Hardware name: ARM-Versatile Express PC is at blocking_notifier_chain_unregister+0x2a/0x78 LR is at blocking_notifier_chain_unregister+0x1b/0x78 Flags: NzCv IRQs on FIQs off Mode SVC_32 ISA Thumb Segment user Control: 70c5387d Table: a57b08c0 DAC: 55555555 Process bash (pid: 518, stack limit = 0x018ebe57) (blocking_notifier_chain_unregister) from (dev_pm_qos_remove_notifier+0x5d/0xb4) (dev_pm_qos_remove_notifier) from (cpufreq_policy_free+0x77/0xc8) (cpufreq_policy_free) from (subsys_interface_unregister+0x4f/0x80) (subsys_interface_unregister) from (cpufreq_unregister_driver+0x29/0x6c) (cpufreq_unregister_driver) from (bL_cpufreq_switcher_notifier+0x41/0x4c) (bL_cpufreq_switcher_notifier) from (notifier_call_chain+0x3d/0x58) (notifier_call_chain) from (blocking_notifier_call_chain+0x29/0x38) (blocking_notifier_call_chain) from (bL_activation_notify+0x13/0x40) (bL_activation_notify) from (bL_switcher_active_store+0x59/0x190) (bL_switcher_active_store) from (kernfs_fop_write+0x85/0x12c) (kernfs_fop_write) from (__vfs_write+0x21/0x130) (__vfs_write) from (vfs_write+0x6b/0xfc) (vfs_write) from (ksys_write+0x6d/0x90) (ksys_write) from (ret_fast_syscall+0x1/0x5a)