cpufreq: Initialize policy->kobj while allocating policy

policy->kobj is required to be initialized once in the lifetime of a
policy.  Currently we are initializing it from __cpufreq_add_dev() and
that doesn't look to be the best place for doing so as we have to do
this on special cases (like: !recover_policy).

We can initialize it from a more obvious place cpufreq_policy_alloc()
and that will make code look cleaner, specially the error handling part.

The error handling part of __cpufreq_add_dev() was doing almost the same
thing while recover_policy is true or false. Fix that as well by always
calling cpufreq_policy_put_kobj() with an additional parameter to skip
notification part of it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 4bfe0a53502fa2107872a3d9546b4730acb2492c..dbb1bd6c57ebcda464fd31d65e33200e3f2a56f9 100644 (file)
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1134,9 +1134,10 @@ static struct cpufreq_policy *cpufreq_policy_restore(unsigned int cpu)
        return policy;
 }
 
-static struct cpufreq_policy *cpufreq_policy_alloc(int cpu)
+static struct cpufreq_policy *cpufreq_policy_alloc(struct device *dev)
 {
        struct cpufreq_policy *policy;
+       int ret;
 
        policy = kzalloc(sizeof(*policy), GFP_KERNEL);
        if (!policy)
@@ -1148,6 +1149,13 @@ static struct cpufreq_policy *cpufreq_policy_alloc(int cpu)
        if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL))
                goto err_free_cpumask;
 
+       ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, &dev->kobj,
+                                  "cpufreq");
+       if (ret) {
+               pr_err("%s: failed to init policy->kobj: %d\n", __func__, ret);
+               goto err_free_rcpumask;
+       }
+
        INIT_LIST_HEAD(&policy->policy_list);
        init_rwsem(&policy->rwsem);
        spin_lock_init(&policy->transition_lock);
@@ -1155,13 +1163,15 @@ static struct cpufreq_policy *cpufreq_policy_alloc(int cpu)
        init_completion(&policy->kobj_unregister);
        INIT_WORK(&policy->update, handle_update);
 
-       policy->cpu = cpu;
+       policy->cpu = dev->id;
 
        /* Set this once on allocation */
-       policy->kobj_cpu = cpu;
+       policy->kobj_cpu = dev->id;
 
        return policy;
 
+err_free_rcpumask:
+       free_cpumask_var(policy->related_cpus);
 err_free_cpumask:
        free_cpumask_var(policy->cpus);
 err_free_policy:
@@ -1170,13 +1180,14 @@ err_free_policy:
        return NULL;
 }
 
-static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy)
+static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy, bool notify)
 {
        struct kobject *kobj;
        struct completion *cmp;
 
-       blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
-                       CPUFREQ_REMOVE_POLICY, policy);
+       if (notify)
+               blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
+                                            CPUFREQ_REMOVE_POLICY, policy);
 
        down_write(&policy->rwsem);
        cpufreq_remove_dev_symlink(policy);
@@ -1270,7 +1281,7 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif)
        policy = recover_policy ? cpufreq_policy_restore(cpu) : NULL;
        if (!policy) {
                recover_policy = false;
-               policy = cpufreq_policy_alloc(cpu);
+               policy = cpufreq_policy_alloc(dev);
                if (!policy)
                        goto nomem_out;
        }
@@ -1310,15 +1321,6 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif)
                policy->user_policy.min = policy->min;
                policy->user_policy.max = policy->max;
 
-               /* prepare interface data */
-               ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq,
-                                          &dev->kobj, "cpufreq");
-               if (ret) {
-                       pr_err("%s: failed to init policy->kobj: %d\n",
-                              __func__, ret);
-                       goto err_init_policy_kobj;
-               }
-
                write_lock_irqsave(&cpufreq_driver_lock, flags);
                for_each_cpu(j, policy->related_cpus)
                        per_cpu(cpufreq_cpu_data, j) = policy;
@@ -1410,18 +1412,12 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif)
 
 err_out_unregister:
 err_get_freq:
-       if (!recover_policy) {
-               kobject_put(&policy->kobj);
-               wait_for_completion(&policy->kobj_unregister);
-       }
-err_init_policy_kobj:
        up_write(&policy->rwsem);
 
        if (cpufreq_driver->exit)
                cpufreq_driver->exit(policy);
 err_set_policy_cpu:
-       if (recover_policy)
-               cpufreq_policy_put_kobj(policy);
+       cpufreq_policy_put_kobj(policy, recover_policy);
        cpufreq_policy_free(policy);
 
 nomem_out:
@@ -1517,7 +1513,7 @@ static int __cpufreq_remove_dev_finish(struct device *dev,
 
        /* Free the policy kobjects only if the driver is getting removed. */
        if (sif)
-               cpufreq_policy_put_kobj(policy);
+               cpufreq_policy_put_kobj(policy, true);
 
        /*
         * Perform the ->exit() even during light-weight tear-down,
@@ -1567,7 +1563,7 @@ static int cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif)
                        return 0;
                }
 
-               cpufreq_policy_put_kobj(policy);
+               cpufreq_policy_put_kobj(policy, true);
                cpufreq_policy_free(policy);
                return 0;
        }