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

1 files changed, 23 insertions, 28 deletions

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index cb003a6b72c8..cf485d928903 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -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;
-
-        down_read(&policy->rwsem);
-
-        ret_freq = __cpufreq_get(cpu);
+        if (policy) {
+                down_read(&policy->rwsem);
+                ret_freq = __cpufreq_get(cpu);
+                up_read(&policy->rwsem);
 
-        up_read(&policy->rwsem);
-        up_read(&cpufreq_rwsem);
+                cpufreq_cpu_put(policy);
+        }
 
         return ret_freq;
 }