[PATCH v4 5/5] thermal: power_allocator: exit early if there are no cooling devices

From: Javi Merino
Date: Wed Aug 26 2015 - 09:27:43 EST

Don't waste cycles in the power allocator governor's throttle function
if there are no cooling devices and exit early.

This commit doesn't change any functionality, but should provide better
performance for the odd case of a thermal zone with trip points but
without cooling devices.

Cc: Zhang Rui <rui.zhang@xxxxxxxxx>
Cc: Eduardo Valentin <edubezval@xxxxxxxxx>
Signed-off-by: Javi Merino <javi.merino@xxxxxxx>
drivers/thermal/power_allocator.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/thermal/power_allocator.c b/drivers/thermal/power_allocator.c
index 85ce0aac9a41..e6fdcf24ba88 100644
--- a/drivers/thermal/power_allocator.c
+++ b/drivers/thermal/power_allocator.c
@@ -348,6 +348,11 @@ static int allocate_power(struct thermal_zone_device *tz,

+ if (!num_actors) {
+ ret = -ENODEV;
+ goto unlock;
+ }
* We need to allocate five arrays of the same size:
* req_power, max_power, granted_power, extra_actor_power and

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/