Commit b70dbf40 authored by Lukasz Luba's avatar Lukasz Luba Committed by Daniel Lezcano
Browse files

thermal/core: Create a helper __thermal_cdev_update() without a lock 

There is a need to have a helper function which updates cooling device
state from the governors code. With this change governor can use
lock and unlock while calling helper function. This avoid unnecessary
second time lock/unlock which was in previous solution present in
governor implementation. This new helper function must be called
with mutex 'cdev->lock' hold.

The changed been discussed and part of code presented in thread:
https://lore.kernel.org/linux-pm/20210419084536.25000-1-lukasz.luba@arm.com/



Co-developed-by: default avatarDaniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: default avatarDaniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: default avatarLukasz Luba <lukasz.luba@arm.com>
Link: https://lore.kernel.org/r/20210422114308.29684-2-lukasz.luba@arm.com
parent 26b2f03d

drivers/thermal/thermal_core.h

+1 −0
Original line number Diff line number Diff line
@@ -66,6 +66,7 @@ static inline bool cdev_is_power_actor(struct thermal_cooling_device *cdev) 
}



void thermal_cdev_update(struct thermal_cooling_device *);

void __thermal_cdev_update(struct thermal_cooling_device *cdev);



/**

 * struct thermal_trip - representation of a point in temperature domain

drivers/thermal/thermal_helpers.c

+17 −10
Original line number Diff line number Diff line
@@ -192,18 +192,11 @@ static void thermal_cdev_set_cur_state(struct thermal_cooling_device *cdev, 
	thermal_cooling_device_stats_update(cdev, target);

}



void thermal_cdev_update(struct thermal_cooling_device *cdev)

void __thermal_cdev_update(struct thermal_cooling_device *cdev)

{

	struct thermal_instance *instance;

	unsigned long target = 0;



	mutex_lock(&cdev->lock);

	/* cooling device is updated*/

	if (cdev->updated) {

		mutex_unlock(&cdev->lock);

		return;

	}



	/* Make sure cdev enters the deepest cooling state */

	list_for_each_entry(instance, &cdev->thermal_instances, cdev_node) {

		dev_dbg(&cdev->device, "zone%d->target=%lu\n",
@@ -216,11 +209,25 @@ void thermal_cdev_update(struct thermal_cooling_device *cdev) 


	thermal_cdev_set_cur_state(cdev, target);



	cdev->updated = true;

	mutex_unlock(&cdev->lock);

	trace_cdev_update(cdev, target);

	dev_dbg(&cdev->device, "set to state %lu\n", target);

}



/**

 * thermal_cdev_update - update cooling device state if needed

 * @cdev:	pointer to struct thermal_cooling_device

 *

 * Update the cooling device state if there is a need.

 */

void thermal_cdev_update(struct thermal_cooling_device *cdev)

{

	mutex_lock(&cdev->lock);

	if (!cdev->updated) {

		__thermal_cdev_update(cdev);

		cdev->updated = true;

	}

	mutex_unlock(&cdev->lock);

}

EXPORT_SYMBOL(thermal_cdev_update);



/**