From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Srivatsa S. Bhat" Subject: [PATCH 2/8] cpufreq: Fix misplaced call to cpufreq_update_policy() Date: Fri, 12 Jul 2013 03:45:56 +0530 Message-ID: <20130711221553.547.56787.stgit@srivatsabhat.in.ibm.com> References: <20130711221419.547.69781.stgit@srivatsabhat.in.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20130711221419.547.69781.stgit@srivatsabhat.in.ibm.com> Sender: linux-kernel-owner@vger.kernel.org To: rjw@sisk.pl, viresh.kumar@linaro.org, toralf.foerster@gmx.de, robert.jarzmik@intel.com, durgadoss.r@intel.com, tianyu.lan@intel.com, lantianyu1986@gmail.com, dirk.brandewie@gmail.com Cc: stern@rowland.harvard.edu, "Srivatsa S. Bhat" , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-pm@vger.kernel.org The call to cpufreq_update_policy() is placed in the CPU hotplug callback of cpufreq_stats, which has a higher priority than the CPU hotplug callback of cpufreq-core. As a result, during CPU_ONLINE/CPU_ONLINE_FROZEN, we end up calling cpufreq_update_policy() *before* calling cpufreq_add_dev() ! And for uninitialized CPUs, it just returns silently, not doing anything. To add to it, cpufreq_stats is not even the right place to call cpufreq_update_policy() to begin with. The cpufreq core ought to handle this in its own callback, from an elegance/relevance perspective. So move the invocation of cpufreq_update_policy() to cpufreq_cpu_callback, and place it *after* cpufreq_add_dev(). Signed-off-by: Srivatsa S. Bhat --- drivers/cpufreq/cpufreq.c | 1 + drivers/cpufreq/cpufreq_stats.c | 6 ------ 2 files changed, 1 insertion(+), 6 deletions(-) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index ccc6eab..f8c3100 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -1943,6 +1943,7 @@ static int __cpuinit cpufreq_cpu_callback(struct notifier_block *nfb, case CPU_ONLINE: case CPU_ONLINE_FROZEN: cpufreq_add_dev(dev, NULL); + cpufreq_update_policy(cpu); break; case CPU_DOWN_PREPARE: case CPU_DOWN_PREPARE_FROZEN: diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c index 12225d1..a3e7475 100644 --- a/drivers/cpufreq/cpufreq_stats.c +++ b/drivers/cpufreq/cpufreq_stats.c @@ -348,10 +348,6 @@ static int __cpuinit cpufreq_stat_cpu_callback(struct notifier_block *nfb, unsigned int cpu = (unsigned long)hcpu; switch (action) { - case CPU_ONLINE: - case CPU_ONLINE_FROZEN: - cpufreq_update_policy(cpu); - break; case CPU_DOWN_PREPARE: case CPU_DOWN_PREPARE_FROZEN: cpufreq_stats_free_sysfs(cpu); @@ -390,8 +386,6 @@ static int __init cpufreq_stats_init(void) return ret; register_hotcpu_notifier(&cpufreq_stat_cpu_notifier); - for_each_online_cpu(cpu) - cpufreq_update_policy(cpu); ret = cpufreq_register_notifier(¬ifier_trans_block, CPUFREQ_TRANSITION_NOTIFIER);