cpufreq: governor: CPUFREQ_GOV_STOP never fails
authorRafael J. Wysocki <rafael.j.wysocki@intel.com>
Thu, 12 May 2016 13:14:12 +0000 (15:14 +0200)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Wed, 18 May 2016 00:28:29 +0000 (02:28 +0200)
None of the cpufreq governors currently in the tree will ever fail
an invocation of the ->governor() callback with the event argument
equal to CPUFREQ_GOV_STOP (unless invoked with incorrect arguments
which doesn't matter anyway) and it is rather difficult to imagine
a valid reason for such a failure.

Accordingly, rearrange the code in the core to make it clear that
this call never fails.

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

index 74ab6f7..d199256 100644 (file)
@@ -83,6 +83,11 @@ static inline void cpufreq_exit_governor(struct cpufreq_policy *policy)
        (void)cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT);
 }
 
+static inline void cpufreq_stop_governor(struct cpufreq_policy *policy)
+{
+       (void)cpufreq_governor(policy, CPUFREQ_GOV_STOP);
+}
+
 /**
  * Two notifier lists: the "policy" list is involved in the
  * validation process for a new CPU frequency policy; the
@@ -1026,13 +1031,8 @@ static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cp
                return 0;
 
        down_write(&policy->rwsem);
-       if (has_target()) {
-               ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP);
-               if (ret) {
-                       pr_err("%s: Failed to stop governor\n", __func__);
-                       goto unlock;
-               }
-       }
+       if (has_target())
+               cpufreq_stop_governor(policy);
 
        cpumask_set_cpu(cpu, policy->cpus);
 
@@ -1041,8 +1041,6 @@ static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cp
                if (ret)
                        pr_err("%s: Failed to start governor\n", __func__);
        }
-
-unlock:
        up_write(&policy->rwsem);
        return ret;
 }
@@ -1354,11 +1352,8 @@ static void cpufreq_offline(unsigned int cpu)
        }
 
        down_write(&policy->rwsem);
-       if (has_target()) {
-               ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP);
-               if (ret)
-                       pr_err("%s: Failed to stop governor\n", __func__);
-       }
+       if (has_target())
+               cpufreq_stop_governor(policy);
 
        cpumask_clear_cpu(cpu, policy->cpus);
 
@@ -1622,7 +1617,6 @@ EXPORT_SYMBOL(cpufreq_generic_suspend);
 void cpufreq_suspend(void)
 {
        struct cpufreq_policy *policy;
-       int ret;
 
        if (!cpufreq_driver)
                return;
@@ -1635,14 +1629,8 @@ void cpufreq_suspend(void)
        for_each_active_policy(policy) {
                if (has_target()) {
                        down_write(&policy->rwsem);
-                       ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP);
+                       cpufreq_stop_governor(policy);
                        up_write(&policy->rwsem);
-
-                       if (ret) {
-                               pr_err("%s: Failed to stop governor for policy: %p\n",
-                                       __func__, policy);
-                               continue;
-                       }
                }
 
                if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy))
@@ -2216,13 +2204,7 @@ static int cpufreq_set_policy(struct cpufreq_policy *policy,
        old_gov = policy->governor;
        /* end old governor */
        if (old_gov) {
-               ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP);
-               if (ret) {
-                       /* This can happen due to race with other operations */
-                       pr_debug("%s: Failed to Stop Governor: %s (%d)\n",
-                                __func__, old_gov->name, ret);
-                       return ret;
-               }
+               cpufreq_stop_governor(policy);
                cpufreq_exit_governor(policy);
        }