cpufreq: Use cpufreq_policy_list for iterating over policies

To iterate over all policies we currently iterate over all online
CPUs and then get the policy for each of them which is suboptimal.
Use the newly created cpufreq_policy_list for this purpose instead.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/cpufreq/cpufreq.c

@@ -961,8 +961,8 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif,
 	struct cpufreq_policy *policy;
 	unsigned long flags;
 #ifdef CONFIG_HOTPLUG_CPU
+	struct cpufreq_policy *tpolicy;
 	struct cpufreq_governor *gov;
-	int sibling;
 #endif
 
 	if (cpu_is_offline(cpu))
@@ -985,11 +985,10 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif,
 #ifdef CONFIG_HOTPLUG_CPU
 	/* Check if this cpu was hot-unplugged earlier and has siblings */
 	read_lock_irqsave(&cpufreq_driver_lock, flags);
-	for_each_online_cpu(sibling) {
-		struct cpufreq_policy *cp = per_cpu(cpufreq_cpu_data, sibling);
-		if (cp && cpumask_test_cpu(cpu, cp->related_cpus)) {
+	list_for_each_entry(tpolicy, &cpufreq_policy_list, policy_list) {
+		if (cpumask_test_cpu(cpu, tpolicy->related_cpus)) {
 			read_unlock_irqrestore(&cpufreq_driver_lock, flags);
-			ret = cpufreq_add_policy_cpu(cp, cpu, dev, frozen);
+			ret = cpufreq_add_policy_cpu(tpolicy, cpu, dev, frozen);
 			up_read(&cpufreq_rwsem);
 			return ret;
 		}