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cpufreq: Fix misplaced call to cpufreq_update_policy()

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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 that, 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 <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Srivatsa S. Bhat 2013-07-30 04:23:56 +05:30 committed by Rafael J. Wysocki
parent c095ba7224
commit 23d328994b
2 changed files with 1 additions and 6 deletions
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1
drivers/cpufreq/cpufreq.c
View File

@ -1945,6 +1945,7 @@ static int 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:

6
drivers/cpufreq/cpufreq_stats.c
View File

@ -348,10 +348,6 @@ static int 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(&notifier_trans_block,
CPUFREQ_TRANSITION_NOTIFIER);