From mboxrd@z Thu Jan 1 00:00:00 1970 From: Viresh Kumar Subject: Re: [RFC PATCH 07/19] cpufreq: assert locking when accessing cpufreq_governor_list Date: Tue, 12 Jan 2016 15:31:22 +0530 Message-ID: <20160112100122.GY1084@ubuntu> References: <1452533760-13787-1-git-send-email-juri.lelli@arm.com> <1452533760-13787-8-git-send-email-juri.lelli@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pf0-f170.google.com ([209.85.192.170]:32939 "EHLO mail-pf0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933472AbcALKB1 (ORCPT ); Tue, 12 Jan 2016 05:01:27 -0500 Received: by mail-pf0-f170.google.com with SMTP id e65so60708859pfe.0 for ; Tue, 12 Jan 2016 02:01:26 -0800 (PST) Content-Disposition: inline In-Reply-To: <1452533760-13787-8-git-send-email-juri.lelli@arm.com> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Juri Lelli Cc: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, peterz@infradead.org, rjw@rjwysocki.net, mturquette@baylibre.com, steve.muckle@linaro.org, vincent.guittot@linaro.org, morten.rasmussen@arm.com, dietmar.eggemann@arm.com On 11-01-16, 17:35, Juri Lelli wrote: > @@ -2025,6 +2027,7 @@ int cpufreq_register_governor(struct cpufreq_governor *governor) > err = -EBUSY; > if (!find_governor(governor->name)) { > err = 0; > + lockdep_assert_held(&cpufreq_governor_mutex); > list_add(&governor->governor_list, &cpufreq_governor_list); > } Why here? This is how the routine looks like: int cpufreq_register_governor(struct cpufreq_governor *governor) { int err; if (!governor) return -EINVAL; if (cpufreq_disabled()) return -ENODEV; mutex_lock(&cpufreq_governor_mutex); governor->initialized = 0; err = -EBUSY; if (!find_governor(governor->name)) { err = 0; list_add(&governor->governor_list, &cpufreq_governor_list); } mutex_unlock(&cpufreq_governor_mutex); return err; } -- viresh