From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932328AbcELNMK (ORCPT ); Thu, 12 May 2016 09:12:10 -0400 Received: from cloudserver094114.home.net.pl ([79.96.170.134]:46869 "HELO cloudserver094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752473AbcELNMH (ORCPT ); Thu, 12 May 2016 09:12:07 -0400 From: "Rafael J. Wysocki" To: Linux PM list Cc: Srinivas Pandruvada , Viresh Kumar , Linux Kernel Mailing List Subject: [PATCH 2/2] cpufreq: governor: CPUFREQ_GOV_STOP never fails Date: Thu, 12 May 2016 15:14:12 +0200 Message-ID: <2034165.RqMO62khMb@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/4.5.0-rc1+; KDE/4.11.5; x86_64; ; ) In-Reply-To: <4540082.RMPf3KxPDh@vostro.rjw.lan> References: <4540082.RMPf3KxPDh@vostro.rjw.lan> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rafael J. Wysocki None of the cpufreq governors currently in the tree will ever fail an invocation of the ->governor() callback with the event argument equal to CPUFREQ_GOV_STOP (unless invoked with incorrect arguments which doesn't matter anyway) and it is rather difficult to imagine a valid reason for such a failure. Accordingly, rearrange the code in the core to make it clear that this call never fails. Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/cpufreq.c | 40 +++++++++++----------------------------- 1 file changed, 11 insertions(+), 29 deletions(-) Index: linux-pm/drivers/cpufreq/cpufreq.c =================================================================== --- linux-pm.orig/drivers/cpufreq/cpufreq.c +++ linux-pm/drivers/cpufreq/cpufreq.c @@ -83,6 +83,11 @@ static inline void cpufreq_exit_governor (void)cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); } +static inline void cpufreq_stop_governor(struct cpufreq_policy *policy) +{ + (void)cpufreq_governor(policy, CPUFREQ_GOV_STOP); +} + /** * Two notifier lists: the "policy" list is involved in the * validation process for a new CPU frequency policy; the @@ -1026,13 +1031,8 @@ static int cpufreq_add_policy_cpu(struct return 0; down_write(&policy->rwsem); - if (has_target()) { - ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP); - if (ret) { - pr_err("%s: Failed to stop governor\n", __func__); - goto unlock; - } - } + if (has_target()) + cpufreq_stop_governor(policy); cpumask_set_cpu(cpu, policy->cpus); @@ -1041,8 +1041,6 @@ static int cpufreq_add_policy_cpu(struct if (ret) pr_err("%s: Failed to start governor\n", __func__); } - -unlock: up_write(&policy->rwsem); return ret; } @@ -1354,11 +1352,8 @@ static void cpufreq_offline(unsigned int } down_write(&policy->rwsem); - if (has_target()) { - ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP); - if (ret) - pr_err("%s: Failed to stop governor\n", __func__); - } + if (has_target()) + cpufreq_stop_governor(policy); cpumask_clear_cpu(cpu, policy->cpus); @@ -1622,7 +1617,6 @@ EXPORT_SYMBOL(cpufreq_generic_suspend); void cpufreq_suspend(void) { struct cpufreq_policy *policy; - int ret; if (!cpufreq_driver) return; @@ -1635,14 +1629,8 @@ void cpufreq_suspend(void) for_each_active_policy(policy) { if (has_target()) { down_write(&policy->rwsem); - ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP); + cpufreq_stop_governor(policy); up_write(&policy->rwsem); - - if (ret) { - pr_err("%s: Failed to stop governor for policy: %p\n", - __func__, policy); - continue; - } } if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy)) @@ -2216,13 +2204,7 @@ static int cpufreq_set_policy(struct cpu old_gov = policy->governor; /* end old governor */ if (old_gov) { - ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP); - if (ret) { - /* This can happen due to race with other operations */ - pr_debug("%s: Failed to Stop Governor: %s (%d)\n", - __func__, old_gov->name, ret); - return ret; - } + cpufreq_stop_governor(policy); cpufreq_exit_governor(policy); }