Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752207Ab3F3S4V (ORCPT ); Sun, 30 Jun 2013 14:56:21 -0400 Received: from e23smtp07.au.ibm.com ([202.81.31.140]:42393 "EHLO e23smtp07.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751691Ab3F3S4S (ORCPT ); Sun, 30 Jun 2013 14:56:18 -0400 Message-ID: <51D07E7F.2030709@linux.vnet.ibm.com> Date: Mon, 01 Jul 2013 00:22:47 +0530 From: "Srivatsa S. Bhat" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120828 Thunderbird/15.0 MIME-Version: 1.0 To: =?UTF-8?B?VG9yYWxmIEbDtnJzdGVy?= CC: "Rafael J. Wysocki" , Viresh Kumar , cpufreq@vger.kernel.org, Linux PM list , "linux-kernel@vger.kernel.org" Subject: [PATCH] cpufreq: Fix cpufreq regression after suspend/resume References: <51C08370.4050906@gmx.de> <51CF1E53.6060902@gmx.de> <8029836.CFiJCXmRQ0@vostro.rjw.lan> <51D05DF4.50704@linux.vnet.ibm.com> <51D06556.7080204@gmx.de> In-Reply-To: <51D06556.7080204@gmx.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13063018-0260-0000-0000-0000033DB5E1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2453 Lines: 65 On 06/30/2013 10:35 PM, Toralf Förster wrote: > On 06/30/2013 06:33 PM, Srivatsa S. Bhat wrote: >> Toralf, can you please >> try out the below patch and see if it improves anything? (Don't revert anything, >> just apply the below diff on a problematic kernel and see if it solves your >> issue). > > applied on top of a66b2e5 - issue went away (either fixed or hidden now) > Cool! So here is the proper patch, with changelog added. Regards, Srivatsa S. Bhat ----------------------------------------------------------------------------- From: Srivatsa S. Bhat Subject: [PATCH] cpufreq: Fix cpufreq regression after suspend/resume Toralf Förster reported that the cpufreq ondemand governor behaves erratically (doesn't scale well) after a suspend/resume cycle. The problem was that the cpufreq subsystem's idea of the cpu frequencies differed from the actual frequencies set in the hardware after a suspend/resume cycle. Toralf bisected the problem to commit a66b2e5 (cpufreq: Preserve sysfs files across suspend/resume). Among other (harmless) things, that commit skipped the call to cpufreq_update_policy() in the resume path. But cpufreq_update_policy() plays an important role during resume, because it is responsible for checking if the BIOS changed the cpu frequencies behind our back and resynchronize the cpufreq subsystem's knowledge of the cpu frequencies, and update them accordingly. So, restore the call to cpufreq_update_policy() in the resume path to fix the cpufreq regression. Reported-by: Toralf Förster Tested-by: Toralf Förster Signed-off-by: Srivatsa S. Bhat --- drivers/cpufreq/cpufreq_stats.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c index fb65dec..591b6fb 100644 --- a/drivers/cpufreq/cpufreq_stats.c +++ b/drivers/cpufreq/cpufreq_stats.c @@ -349,6 +349,7 @@ static int __cpuinit cpufreq_stat_cpu_callback(struct notifier_block *nfb, switch (action) { case CPU_ONLINE: + case CPU_ONLINE_FROZEN: cpufreq_update_policy(cpu); break; case CPU_DOWN_PREPARE: -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/