From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753159Ab3ILMEN (ORCPT ); Thu, 12 Sep 2013 08:04:13 -0400 Received: from e32.co.us.ibm.com ([32.97.110.150]:50086 "EHLO e32.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751778Ab3ILMEL (ORCPT ); Thu, 12 Sep 2013 08:04:11 -0400 From: "Srivatsa S. Bhat" Subject: [PATCH] cpufreq: Detect spurious invocations of update_policy_cpu() To: rjw@sisk.pl, viresh.kumar@linaro.org, swarren@wwwdotorg.org Cc: cpufreq@vger.kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, "Srivatsa S. Bhat" Date: Thu, 12 Sep 2013 17:29:09 +0530 Message-ID: <20130912115710.25951.98497.stgit@srivatsabhat.in.ibm.com> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13091212-0928-0000-0000-000001A196BD Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The function update_policy_cpu() is expected to be called when the policy->cpu of a cpufreq policy is to be changed: ie., the new CPU nominated to become the policy->cpu is different from the old one. Print a warning if it is invoked with new_cpu == old_cpu, since such an invocation might hint at a faulty logic in the caller. Suggested-by: Viresh Kumar Signed-off-by: Srivatsa S. Bhat --- drivers/cpufreq/cpufreq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 43c24aa..2084132 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -949,7 +949,7 @@ static void cpufreq_policy_free(struct cpufreq_policy *policy) static void update_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) { - if (cpu == policy->cpu) + if (WARN_ON(cpu == policy->cpu)) return; policy->last_cpu = policy->cpu;