cpufreq: governor: Get rid of governor events

The design of the cpufreq governor API is not very straightforward,
as struct cpufreq_governor provides only one callback to be invoked
from different code paths for different purposes.  The purpose it is
invoked for is determined by its second "event" argument, causing it
to act as a "callback multiplexer" of sorts.

Unfortunately, that leads to extra complexity in governors, some of
which implement the ->governor() callback as a switch statement
that simply checks the event argument and invokes a separate function
to handle that specific event.

That extra complexity can be eliminated by replacing the all-purpose
->governor() callback with a family of callbacks to carry out specific
governor operations: initialization and exit, start and stop and policy
limits updates.  That also turns out to reduce the code size too, so
do it.

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

1 files changed, 52 insertions, 52 deletions

diff --git a/drivers/cpufreq/cpufreq_userspace.c b/drivers/cpufreq/cpufreq_userspace.c
index 9f3dec9..bd897e3 100644
--- a/drivers/cpufreq/cpufreq_userspace.c
+++ b/drivers/cpufreq/cpufreq_userspace.c
@@ -65,66 +65,66 @@ static int cpufreq_userspace_policy_init(struct cpufreq_policy *policy)
 	return 0;
 }
 
-static int cpufreq_governor_userspace(struct cpufreq_policy *policy,
-				   unsigned int event)
+static void cpufreq_userspace_policy_exit(struct cpufreq_policy *policy)
+{
+	mutex_lock(&userspace_mutex);
+	kfree(policy->governor_data);
+	policy->governor_data = NULL;
+	mutex_unlock(&userspace_mutex);
+}
+
+static int cpufreq_userspace_policy_start(struct cpufreq_policy *policy)
 {
 	unsigned int *setspeed = policy->governor_data;
-	unsigned int cpu = policy->cpu;
-	int rc = 0;
 
-	if (event == CPUFREQ_GOV_POLICY_INIT)
-		return cpufreq_userspace_policy_init(policy);
+	BUG_ON(!policy->cur);
+	pr_debug("started managing cpu %u\n", policy->cpu);
 
-	if (!setspeed)
-		return -EINVAL;
-
-	switch (event) {
-	case CPUFREQ_GOV_POLICY_EXIT:
-		mutex_lock(&userspace_mutex);
-		policy->governor_data = NULL;
-		kfree(setspeed);
-		mutex_unlock(&userspace_mutex);
-		break;
-	case CPUFREQ_GOV_START:
-		BUG_ON(!policy->cur);
-		pr_debug("started managing cpu %u\n", cpu);
-
-		mutex_lock(&userspace_mutex);
-		per_cpu(cpu_is_managed, cpu) = 1;
-		*setspeed = policy->cur;
-		mutex_unlock(&userspace_mutex);
-		break;
-	case CPUFREQ_GOV_STOP:
-		pr_debug("managing cpu %u stopped\n", cpu);
-
-		mutex_lock(&userspace_mutex);
-		per_cpu(cpu_is_managed, cpu) = 0;
-		*setspeed = 0;
-		mutex_unlock(&userspace_mutex);
-		break;
-	case CPUFREQ_GOV_LIMITS:
-		mutex_lock(&userspace_mutex);
-		pr_debug("limit event for cpu %u: %u - %u kHz, currently %u kHz, last set to %u kHz\n",
-			cpu, policy->min, policy->max, policy->cur, *setspeed);
-
-		if (policy->max < *setspeed)
-			__cpufreq_driver_target(policy, policy->max,
-						CPUFREQ_RELATION_H);
-		else if (policy->min > *setspeed)
-			__cpufreq_driver_target(policy, policy->min,
-						CPUFREQ_RELATION_L);
-		else
-			__cpufreq_driver_target(policy, *setspeed,
-						CPUFREQ_RELATION_L);
-		mutex_unlock(&userspace_mutex);
-		break;
-	}
-	return rc;
+	mutex_lock(&userspace_mutex);
+	per_cpu(cpu_is_managed, policy->cpu) = 1;
+	*setspeed = policy->cur;
+	mutex_unlock(&userspace_mutex);
+	return 0;
+}
+
+static void cpufreq_userspace_policy_stop(struct cpufreq_policy *policy)
+{
+	unsigned int *setspeed = policy->governor_data;
+
+	pr_debug("managing cpu %u stopped\n", policy->cpu);
+
+	mutex_lock(&userspace_mutex);
+	per_cpu(cpu_is_managed, policy->cpu) = 0;
+	*setspeed = 0;
+	mutex_unlock(&userspace_mutex);
+}
+
+static void cpufreq_userspace_policy_limits(struct cpufreq_policy *policy)
+{
+	unsigned int *setspeed = policy->governor_data;
+
+	mutex_lock(&userspace_mutex);
+
+	pr_debug("limit event for cpu %u: %u - %u kHz, currently %u kHz, last set to %u kHz\n",
+		 policy->cpu, policy->min, policy->max, policy->cur, *setspeed);
+
+	if (policy->max < *setspeed)
+		__cpufreq_driver_target(policy, policy->max, CPUFREQ_RELATION_H);
+	else if (policy->min > *setspeed)
+		__cpufreq_driver_target(policy, policy->min, CPUFREQ_RELATION_L);
+	else
+		__cpufreq_driver_target(policy, *setspeed, CPUFREQ_RELATION_L);
+
+	mutex_unlock(&userspace_mutex);
 }
 
 static struct cpufreq_governor cpufreq_gov_userspace = {
 	.name		= "userspace",
-	.governor	= cpufreq_governor_userspace,
+	.init		= cpufreq_userspace_policy_init,
+	.exit		= cpufreq_userspace_policy_exit,
+	.start		= cpufreq_userspace_policy_start,
+	.stop		= cpufreq_userspace_policy_stop,
+	.limits		= cpufreq_userspace_policy_limits,
 	.store_setspeed	= cpufreq_set,
 	.show_setspeed	= show_speed,
 	.owner		= THIS_MODULE,