From patchwork Mon Jan 11 17:35:56 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Juri Lelli X-Patchwork-Id: 59561 Delivered-To: patch@linaro.org Received: by 10.112.130.2 with SMTP id oa2csp2252528lbb; Mon, 11 Jan 2016 09:39:02 -0800 (PST) X-Received: by 10.98.69.209 with SMTP id n78mr27219622pfi.81.1452533942537; Mon, 11 Jan 2016 09:39:02 -0800 (PST) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id r72si29730960pfa.200.2016.01.11.09.39.02; Mon, 11 Jan 2016 09:39:02 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934110AbcAKRjA (ORCPT + 29 others); Mon, 11 Jan 2016 12:39:00 -0500 Received: from foss.arm.com ([217.140.101.70]:57292 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761281AbcAKRhn (ORCPT ); Mon, 11 Jan 2016 12:37:43 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 1D1785ED; Mon, 11 Jan 2016 09:37:08 -0800 (PST) Received: from e106622-lin.cambridge.arm.com (e106622-lin.cambridge.arm.com [10.1.208.152]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 12ECD3F24D; Mon, 11 Jan 2016 09:37:40 -0800 (PST) From: Juri Lelli To: linux-kernel@vger.kernel.org Cc: linux-pm@vger.kernel.org, peterz@infradead.org, rjw@rjwysocki.net, viresh.kumar@linaro.org, mturquette@baylibre.com, steve.muckle@linaro.org, vincent.guittot@linaro.org, morten.rasmussen@arm.com, dietmar.eggemann@arm.com, juri.lelli@arm.com Subject: [RFC PATCH 15/19] cpufreq: remove useless usage of cpufreq_governor_mutex in __cpufreq_governor Date: Mon, 11 Jan 2016 17:35:56 +0000 Message-Id: <1452533760-13787-16-git-send-email-juri.lelli@arm.com> X-Mailer: git-send-email 2.2.2 In-Reply-To: <1452533760-13787-1-git-send-email-juri.lelli@arm.com> References: <1452533760-13787-1-git-send-email-juri.lelli@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit 6f1e4efd882e ("cpufreq: Fix timer/workqueue corruption by protecting reading governor_enabled") made policy->governor_enabled guarded by cpufreq_governor_mutex in __cpufreq_governor. Now that holding of policy->rwsem is asserted in __cpufreq_governor, cpufreq_governor_mutex is overkilling. Remove such usage. Also, this cleans up semantic of cpufreq_governor_mutex: it guards cpufreq_governor_list only. Cc: "Rafael J. Wysocki" Cc: Viresh Kumar Signed-off-by: Juri Lelli --- drivers/cpufreq/cpufreq.c | 6 ------ 1 file changed, 6 deletions(-) -- 2.2.2 diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index ba452c3..d58a622 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -1993,11 +1993,9 @@ static int __cpufreq_governor(struct cpufreq_policy *policy, pr_debug("%s: for CPU %u, event %u\n", __func__, policy->cpu, event); - mutex_lock(&cpufreq_governor_mutex); if ((policy->governor_enabled && event == CPUFREQ_GOV_START) || (!policy->governor_enabled && (event == CPUFREQ_GOV_LIMITS || event == CPUFREQ_GOV_STOP))) { - mutex_unlock(&cpufreq_governor_mutex); return -EBUSY; } @@ -2006,8 +2004,6 @@ static int __cpufreq_governor(struct cpufreq_policy *policy, else if (event == CPUFREQ_GOV_START) policy->governor_enabled = true; - mutex_unlock(&cpufreq_governor_mutex); - ret = policy->governor->governor(policy, event); if (!ret) { @@ -2017,12 +2013,10 @@ static int __cpufreq_governor(struct cpufreq_policy *policy, policy->governor->initialized--; } else { /* Restore original values */ - mutex_lock(&cpufreq_governor_mutex); if (event == CPUFREQ_GOV_STOP) policy->governor_enabled = true; else if (event == CPUFREQ_GOV_START) policy->governor_enabled = false; - mutex_unlock(&cpufreq_governor_mutex); } if (((event == CPUFREQ_GOV_POLICY_INIT) && ret) ||