cpufreq: Create for_each_{in}active_policy()
policy->cpus is cleared unconditionally now on hotplug-out of a CPU and
it can be checked to know if a policy is active or not. Create helper
routines to iterate over all active/inactive policies, based on
policy->cpus field.
Replace all instances of for_each_policy() with for_each_active_policy()
to make them iterate only for active policies. (We haven't made changes
yet to keep inactive policies in the same list, but that will be
followed in a later patch).
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 8cf0c0e..74d9fcb 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -31,10 +31,62 @@
#include <linux/tick.h>
#include <trace/events/power.h>
-/* Macros to iterate over lists */
-/* Iterate over online CPUs policies */
static LIST_HEAD(cpufreq_policy_list);
-#define for_each_policy(__policy) \
+
+static inline bool policy_is_inactive(struct cpufreq_policy *policy)
+{
+ return cpumask_empty(policy->cpus);
+}
+
+static bool suitable_policy(struct cpufreq_policy *policy, bool active)
+{
+ return active == !policy_is_inactive(policy);
+}
+
+/* Finds Next Acive/Inactive policy */
+static struct cpufreq_policy *next_policy(struct cpufreq_policy *policy,
+ bool active)
+{
+ do {
+ policy = list_next_entry(policy, policy_list);
+
+ /* No more policies in the list */
+ if (&policy->policy_list == &cpufreq_policy_list)
+ return NULL;
+ } while (!suitable_policy(policy, active));
+
+ return policy;
+}
+
+static struct cpufreq_policy *first_policy(bool active)
+{
+ struct cpufreq_policy *policy;
+
+ /* No policies in the list */
+ if (list_empty(&cpufreq_policy_list))
+ return NULL;
+
+ policy = list_first_entry(&cpufreq_policy_list, typeof(*policy),
+ policy_list);
+
+ if (!suitable_policy(policy, active))
+ policy = next_policy(policy, active);
+
+ return policy;
+}
+
+/* Macros to iterate over CPU policies */
+#define for_each_suitable_policy(__policy, __active) \
+ for (__policy = first_policy(__active); \
+ __policy; \
+ __policy = next_policy(__policy, __active))
+
+#define for_each_active_policy(__policy) \
+ for_each_suitable_policy(__policy, true)
+#define for_each_inactive_policy(__policy) \
+ for_each_suitable_policy(__policy, false)
+
+#define for_each_policy(__policy) \
list_for_each_entry(__policy, &cpufreq_policy_list, policy_list)
/* Iterate over governors */
@@ -1156,7 +1208,7 @@
/* Check if this CPU already has a policy to manage it */
read_lock_irqsave(&cpufreq_driver_lock, flags);
- for_each_policy(policy) {
+ for_each_active_policy(policy) {
if (cpumask_test_cpu(cpu, policy->related_cpus)) {
read_unlock_irqrestore(&cpufreq_driver_lock, flags);
ret = cpufreq_add_policy_cpu(policy, cpu, dev);
@@ -1674,7 +1726,7 @@
pr_debug("%s: Suspending Governors\n", __func__);
- for_each_policy(policy) {
+ for_each_active_policy(policy) {
if (__cpufreq_governor(policy, CPUFREQ_GOV_STOP))
pr_err("%s: Failed to stop governor for policy: %p\n",
__func__, policy);
@@ -1708,7 +1760,7 @@
pr_debug("%s: Resuming Governors\n", __func__);
- for_each_policy(policy) {
+ for_each_active_policy(policy) {
if (cpufreq_driver->resume && cpufreq_driver->resume(policy))
pr_err("%s: Failed to resume driver: %p\n", __func__,
policy);
@@ -2354,7 +2406,7 @@
struct cpufreq_policy *policy;
int ret = -EINVAL;
- for_each_policy(policy) {
+ for_each_active_policy(policy) {
freq_table = cpufreq_frequency_get_table(policy->cpu);
if (freq_table) {
ret = cpufreq_frequency_table_cpuinfo(policy,