Re: [RFC PATCH 07/19] cpufreq: assert locking when accessing cpufreq_governor_list

From: Viresh Kumar
Date: Tue Jan 12 2016 - 05:01:34 EST


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