Commit 19bc45a5 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

Merge branch 'pm-cpufreq' 

* pm-cpufreq:
  cpufreq: Initialize governor for a new policy under policy->rwsem
  cpufreq: Initialize policy before making it available for others to use
  cpufreq: use cpufreq_cpu_get() to avoid cpufreq_get() race conditions
parents beb0082e 4e97b631

drivers/cpufreq/cpufreq.c

+23 −28
Original line number Diff line number Diff line
@@ -1109,6 +1109,21 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, 
		goto err_set_policy_cpu;

	}



	/* related cpus should atleast have policy->cpus */

	cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus);



	/*

	 * affected cpus must always be the one, which are online. We aren't

	 * managing offline cpus here.

	 */

	cpumask_and(policy->cpus, policy->cpus, cpu_online_mask);



	if (!frozen) {

		policy->user_policy.min = policy->min;

		policy->user_policy.max = policy->max;

	}



	down_write(&policy->rwsem);

	write_lock_irqsave(&cpufreq_driver_lock, flags);

	for_each_cpu(j, policy->cpus)

		per_cpu(cpufreq_cpu_data, j) = policy;
@@ -1162,20 +1177,6 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, 
		}

	}



	/* related cpus should atleast have policy->cpus */

	cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus);



	/*

	 * affected cpus must always be the one, which are online. We aren't

	 * managing offline cpus here.

	 */

	cpumask_and(policy->cpus, policy->cpus, cpu_online_mask);



	if (!frozen) {

		policy->user_policy.min = policy->min;

		policy->user_policy.max = policy->max;

	}



	blocking_notifier_call_chain(&cpufreq_policy_notifier_list,

				     CPUFREQ_START, policy);
@@ -1206,6 +1207,7 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, 
		policy->user_policy.policy = policy->policy;

		policy->user_policy.governor = policy->governor;

	}

	up_write(&policy->rwsem);



	kobject_uevent(&policy->kobj, KOBJ_ADD);

	up_read(&cpufreq_rwsem);
@@ -1546,23 +1548,16 @@ static unsigned int __cpufreq_get(unsigned int cpu) 
 */

unsigned int cpufreq_get(unsigned int cpu)

{

	struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);

	struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);

	unsigned int ret_freq = 0;



	if (cpufreq_disabled() || !cpufreq_driver)

		return -ENOENT;



	BUG_ON(!policy);



	if (!down_read_trylock(&cpufreq_rwsem))

		return 0;



	if (policy) {

		down_read(&policy->rwsem);



		ret_freq = __cpufreq_get(cpu);



		up_read(&policy->rwsem);

	up_read(&cpufreq_rwsem);



		cpufreq_cpu_put(policy);

	}



	return ret_freq;

}