From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758221AbdCVBCb (ORCPT ); Tue, 21 Mar 2017 21:02:31 -0400 Received: from cloudserver094114.home.net.pl ([79.96.170.134]:58513 "EHLO cloudserver094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757730AbdCVBC3 (ORCPT ); Tue, 21 Mar 2017 21:02:29 -0400 From: "Rafael J. Wysocki" To: Linux PM Cc: LKML , Viresh Kumar , Peter Zijlstra , Patrick Bellasi , Vincent Guittot Subject: [PATCH] cpufreq: schedutil: Always trace frequency if it does not change Date: Wed, 22 Mar 2017 01:56:53 +0100 Message-ID: <10655562.4O9KtquB0A@aspire.rjw.lan> User-Agent: KMail/4.14.10 (Linux/4.10.0+; KDE/4.14.9; x86_64; ; ) MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rafael J. Wysocki sugov_update_commit() calls trace_cpu_frequency() to record the current CPU frequency if it has not changed in the fast switch case to prevent utilities from getting confused (they may report that the CPU is idle if the frequency has not been recorded for too long, for example). However, the same problem may occur for a cpufreq driver that doesn't support fast frequency switching and implements the ->target callback (that is, it doesn't use frequency tables), but trace_cpu_frequency() is not called if frequency updates are skipped in that case. For this reason, modify sugov_update_commit() to always call trace_cpu_frequency() when the new frequency to be set is equal to the one that was set previously and reorganize the code in there to reduce duplication somewhat. Signed-off-by: Rafael J. Wysocki --- kernel/sched/cpufreq_schedutil.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) Index: linux-pm/kernel/sched/cpufreq_schedutil.c =================================================================== --- linux-pm.orig/kernel/sched/cpufreq_schedutil.c +++ linux-pm/kernel/sched/cpufreq_schedutil.c @@ -98,22 +98,22 @@ static void sugov_update_commit(struct s { struct cpufreq_policy *policy = sg_policy->policy; + if (sg_policy->next_freq == next_freq) { + trace_cpu_frequency(policy->cur, smp_processor_id()); + return; + } + + sg_policy->next_freq = next_freq; + sg_policy->last_freq_update_time = time; + if (policy->fast_switch_enabled) { - if (sg_policy->next_freq == next_freq) { - trace_cpu_frequency(policy->cur, smp_processor_id()); - return; - } - sg_policy->next_freq = next_freq; - sg_policy->last_freq_update_time = time; next_freq = cpufreq_driver_fast_switch(policy, next_freq); if (next_freq == CPUFREQ_ENTRY_INVALID) return; policy->cur = next_freq; trace_cpu_frequency(next_freq, smp_processor_id()); - } else if (sg_policy->next_freq != next_freq) { - sg_policy->next_freq = next_freq; - sg_policy->last_freq_update_time = time; + } else { sg_policy->work_in_progress = true; irq_work_queue(&sg_policy->irq_work); }