From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: [PATCH] cpufreq: stats: Walk online CPUs with CPU offline/online locked Date: Fri, 20 May 2016 03:34:51 +0200 Message-ID: <19792191.esL3UuyORb@vostro.rjw.lan> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7Bit Return-path: Received: from cloudserver094114.home.net.pl ([79.96.170.134]:42186 "HELO cloudserver094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1754038AbcETBbU (ORCPT ); Thu, 19 May 2016 21:31:20 -0400 Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Linux PM list Cc: Linux Kernel Mailing List , Viresh Kumar , Srinivas Pandruvada From: Rafael J. Wysocki Loops over online CPUs in cpufreq_stats_init() and cpufreq_stats_exit() should be carried out with CPU offline/online locked or races are possible otherwise, so make that happen. Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/cpufreq_stats.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) Index: linux-pm/drivers/cpufreq/cpufreq_stats.c =================================================================== --- linux-pm.orig/drivers/cpufreq/cpufreq_stats.c +++ linux-pm/drivers/cpufreq/cpufreq_stats.c @@ -322,6 +322,8 @@ static int __init cpufreq_stats_init(voi if (ret) return ret; + get_online_cpus(); + for_each_online_cpu(cpu) cpufreq_stats_create_table(cpu); @@ -332,21 +334,27 @@ static int __init cpufreq_stats_init(voi CPUFREQ_POLICY_NOTIFIER); for_each_online_cpu(cpu) cpufreq_stats_free_table(cpu); - return ret; } - return 0; + put_online_cpus(); + + return ret; } static void __exit cpufreq_stats_exit(void) { unsigned int cpu; + get_online_cpus(); + cpufreq_unregister_notifier(¬ifier_policy_block, CPUFREQ_POLICY_NOTIFIER); cpufreq_unregister_notifier(¬ifier_trans_block, CPUFREQ_TRANSITION_NOTIFIER); + for_each_online_cpu(cpu) cpufreq_stats_free_table(cpu); + + put_online_cpus(); } MODULE_AUTHOR("Zou Nan hai ");