[PATCH v6 1/8] cpufreq: Store cpufreq policies in a list

Lukasz Majewski
2013-07-25T16:34:10Z

Policies available in a cpufreq framework are now linked together. They are
accessible via cpufreq_policy_list defined at cpufreq core.

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Myungjoo Ham <myungjoo.ham@samsung.com>

---
Changes for v6:
- Move policy list entry delete code to __cpufreq_remove_dev()
- Protect operations on cpufreq_policy_list elements with lock

Changes for v5:
- Call list_add() only when device successfully added

Changes for v4:
- New patch

drivers/cpufreq/cpufreq.c | 9 +++++++++
include/linux/cpufreq.h | 1 +
2 files changed, 10 insertions(+)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 0937b8d..172a25e 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -46,6 +46,7 @@ static struct cpufreq_driver *cpufreq_driver;
static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data);
static DEFINE_RWLOCK(cpufreq_driver_lock);
static DEFINE_MUTEX(cpufreq_governor_lock);
+static LIST_HEAD(cpufreq_policy_list);

#ifdef CONFIG_HOTPLUG_CPU
/* This one keeps track of the previously set governor of a removed CPU */
@@ -1054,6 +1055,10 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif)
if (ret)
goto err_out_unregister;

+ write_lock_irqsave(&cpufreq_driver_lock, flags);
+ list_add(&policy->policy_list, &cpufreq_policy_list);
+ write_unlock_irqrestore(&cpufreq_driver_lock, flags);
+
kobject_uevent(&policy->kobj, KOBJ_ADD);
module_put(cpufreq_driver->owner);
pr_debug("initialization complete\n");
@@ -1202,6 +1207,10 @@ static int __cpufreq_remove_dev(struct device *dev,
if (cpufreq_driver->exit)
cpufreq_driver->exit(data);

+ write_lock_irqsave(&cpufreq_driver_lock, flags);
+ list_del(&data->policy_list);
+ write_unlock_irqrestore(&cpufreq_driver_lock, flags);
+
free_cpumask_var(data->related_cpus);
free_cpumask_var(data->cpus);
kfree(data);
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 90d5a15..d8e30fc 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -117,6 +117,7 @@ struct cpufreq_policy {

struct cpufreq_real_policy user_policy;

+ struct list_head policy_list;
struct kobject kobj;
struct completion kobj_unregister;
int transition_ongoing; /* Tracks transition status */
--
1.7.10.4