From patchwork Mon Jan 11 17:35:45 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Juri Lelli X-Patchwork-Id: 8007521 Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 2DCF2BEEE5 for ; Mon, 11 Jan 2016 17:42:33 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 08FA12026C for ; Mon, 11 Jan 2016 17:42:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 14F1E201FE for ; Mon, 11 Jan 2016 17:42:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760489AbcAKRhV (ORCPT ); Mon, 11 Jan 2016 12:37:21 -0500 Received: from foss.arm.com ([217.140.101.70]:57226 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758586AbcAKRhT (ORCPT ); Mon, 11 Jan 2016 12:37:19 -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 9AFFE5EE; Mon, 11 Jan 2016 09:36:44 -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 8E2053F24D; Mon, 11 Jan 2016 09:37:17 -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 04/19] cpufreq: bring data structures close to their locks Date: Mon, 11 Jan 2016 17:35:45 +0000 Message-Id: <1452533760-13787-5-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-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Currently it is not easy to figure out which lock/mutex protects which data structure. Clean things up by moving data structures and their locks/mutexs closer; also, change comments to document relations further. Cc: "Rafael J. Wysocki" Cc: Viresh Kumar Signed-off-by: Juri Lelli Acked-by: Viresh Kumar --- drivers/cpufreq/cpufreq.c | 33 ++++++++++++++++++--------------- 1 file changed, 18 insertions(+), 15 deletions(-) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 2e41356..00a00cd 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -31,7 +31,25 @@ #include #include +/** + * Iterate over governors + * + * cpufreq_governor_list is protected by cpufreq_governor_mutex. + */ +static LIST_HEAD(cpufreq_governor_list); +static DEFINE_MUTEX(cpufreq_governor_mutex); +#define for_each_governor(__governor) \ + list_for_each_entry(__governor, &cpufreq_governor_list, governor_list) + +/** + * The "cpufreq driver" - the arch- or hardware-dependent low + * level driver of CPUFreq support, and its spinlock (cpufreq_driver_lock). + * This lock also protects cpufreq_cpu_data array and cpufreq_policy_list. + */ +static struct cpufreq_driver *cpufreq_driver; +static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); static LIST_HEAD(cpufreq_policy_list); +static DEFINE_RWLOCK(cpufreq_driver_lock); static inline bool policy_is_inactive(struct cpufreq_policy *policy) { @@ -86,21 +104,6 @@ static struct cpufreq_policy *first_policy(bool active) #define for_each_inactive_policy(__policy) \ for_each_suitable_policy(__policy, false) -/* Iterate over governors */ -static LIST_HEAD(cpufreq_governor_list); -#define for_each_governor(__governor) \ - list_for_each_entry(__governor, &cpufreq_governor_list, governor_list) - -/** - * The "cpufreq driver" - the arch- or hardware-dependent low - * level driver of CPUFreq support, and its spinlock. This lock - * also protects the cpufreq_cpu_data array. - */ -static struct cpufreq_driver *cpufreq_driver; -static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); -static DEFINE_RWLOCK(cpufreq_driver_lock); -static DEFINE_MUTEX(cpufreq_governor_mutex); - /* Flag to suspend/resume CPUFreq governors */ static bool cpufreq_suspended;