Commit e0288b0e authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

Merge branch 'pm-opp' 

* pm-opp:
  PM / OPP: take RCU lock in dev_pm_opp_get_opp_count
  PM / OPP: fix warning in of_free_opp_table()
  PM / OPP: add some lockdep annotations
parents b7392d22 b4718c02

drivers/base/power/opp.c

+31 −8
Original line number Diff line number Diff line
@@ -108,6 +108,14 @@ static LIST_HEAD(dev_opp_list); 
/* Lock to allow exclusive modification to the device and opp lists */

static DEFINE_MUTEX(dev_opp_list_lock);



#define opp_rcu_lockdep_assert()					\

do {									\

	rcu_lockdep_assert(rcu_read_lock_held() ||			\

				lockdep_is_held(&dev_opp_list_lock),	\

			   "Missing rcu_read_lock() or "		\

			   "dev_opp_list_lock protection");		\

} while (0)



/**

 * find_device_opp() - find device_opp struct using device pointer

 * @dev:	device pointer used to lookup device OPPs
@@ -208,9 +216,7 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_get_freq); 
 * This function returns the number of available opps if there are any,

 * else returns 0 if none or the corresponding error value.

 *

 * Locking: This function must be called under rcu_read_lock(). This function

 * internally references two RCU protected structures: device_opp and opp which

 * are safe as long as we are under a common RCU locked section.

 * Locking: This function takes rcu_read_lock().

 */

int dev_pm_opp_get_opp_count(struct device *dev)

{
@@ -218,11 +224,14 @@ int dev_pm_opp_get_opp_count(struct device *dev) 
	struct dev_pm_opp *temp_opp;

	int count = 0;



	rcu_read_lock();



	dev_opp = find_device_opp(dev);

	if (IS_ERR(dev_opp)) {

		int r = PTR_ERR(dev_opp);

		dev_err(dev, "%s: device OPP not found (%d)\n", __func__, r);

		return r;

		count = PTR_ERR(dev_opp);

		dev_err(dev, "%s: device OPP not found (%d)\n",

			__func__, count);

		goto out_unlock;

	}



	list_for_each_entry_rcu(temp_opp, &dev_opp->opp_list, node) {
@@ -230,6 +239,8 @@ int dev_pm_opp_get_opp_count(struct device *dev) 
			count++;

	}



out_unlock:

	rcu_read_unlock();

	return count;

}

EXPORT_SYMBOL_GPL(dev_pm_opp_get_opp_count);
@@ -267,6 +278,8 @@ struct dev_pm_opp *dev_pm_opp_find_freq_exact(struct device *dev, 
	struct device_opp *dev_opp;

	struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);



	opp_rcu_lockdep_assert();



	dev_opp = find_device_opp(dev);

	if (IS_ERR(dev_opp)) {

		int r = PTR_ERR(dev_opp);
@@ -313,6 +326,8 @@ struct dev_pm_opp *dev_pm_opp_find_freq_ceil(struct device *dev, 
	struct device_opp *dev_opp;

	struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);



	opp_rcu_lockdep_assert();



	if (!dev || !freq) {

		dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq);

		return ERR_PTR(-EINVAL);
@@ -361,6 +376,8 @@ struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev, 
	struct device_opp *dev_opp;

	struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);



	opp_rcu_lockdep_assert();



	if (!dev || !freq) {

		dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq);

		return ERR_PTR(-EINVAL);
@@ -783,9 +800,15 @@ void of_free_opp_table(struct device *dev) 


	/* Check for existing list for 'dev' */

	dev_opp = find_device_opp(dev);

	if (WARN(IS_ERR(dev_opp), "%s: dev_opp: %ld\n", dev_name(dev),

		 PTR_ERR(dev_opp)))

	if (IS_ERR(dev_opp)) {

		int error = PTR_ERR(dev_opp);

		if (error != -ENODEV)

			WARN(1, "%s: dev_opp: %d\n",

			     IS_ERR_OR_NULL(dev) ?

					"Invalid device" : dev_name(dev),

			     error);

		return;

	}



	/* Hold our list modification lock here */

	mutex_lock(&dev_opp_list_lock);