cpufreq: Store cpufreq policies in a list

Policies available in the cpufreq framework are now linked together.
They are accessible via cpufreq_policy_list defined in the cpufreq
core.

[rjw: Fix from Yinghai Lu folded in]
Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Myungjoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 9e83d9142072..75c5bd424d59 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -40,6 +40,7 @@ static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data);
 static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data_fallback);
 static DEFINE_RWLOCK(cpufreq_driver_lock);
 static DEFINE_MUTEX(cpufreq_governor_lock);
+static LIST_HEAD(cpufreq_policy_list);
 
 #ifdef CONFIG_HOTPLUG_CPU
 /* This one keeps track of the previously set governor of a removed CPU */
@@ -952,6 +953,7 @@ static struct cpufreq_policy *cpufreq_policy_alloc(void)
         if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL))
                 goto err_free_cpumask;
 
+        INIT_LIST_HEAD(&policy->policy_list);
         return policy;
 
 err_free_cpumask:
@@ -964,6 +966,12 @@ err_free_policy:
 
 static void cpufreq_policy_free(struct cpufreq_policy *policy)
 {
+        unsigned long flags;
+
+        write_lock_irqsave(&cpufreq_driver_lock, flags);
+        list_del(&policy->policy_list);
+        write_unlock_irqrestore(&cpufreq_driver_lock, flags);
+
         free_cpumask_var(policy->related_cpus);
         free_cpumask_var(policy->cpus);
         kfree(policy);
@@ -1077,6 +1085,10 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif,
                 ret = cpufreq_add_dev_interface(policy, dev);
                 if (ret)
                         goto err_out_unregister;
+
+                write_lock_irqsave(&cpufreq_driver_lock, flags);
+                list_add(&policy->policy_list, &cpufreq_policy_list);
+                write_unlock_irqrestore(&cpufreq_driver_lock, flags);
         }
 
         cpufreq_init_policy(policy);