[PATCH] thermal: step_wise: cdev only needs update on a new target state

[PATCH] thermal: step_wise: cdev only needs update on a new target state

[Shawn Guo]

The cooling device only needs update on a new target state.  Since we
already check old target in thermal_zone_trip_update(), we can do one
more check to see if it's a new target state.  If not, we can reasonably
save some uncecesary code execution.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
---
 drivers/thermal/step_wise.c |    3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/thermal/step_wise.c b/drivers/thermal/step_wise.c
index 4d4ddae..0afbd86 100644
--- a/drivers/thermal/step_wise.c
+++ b/drivers/thermal/step_wise.c
@@ -133,6 +133,9 @@ static void thermal_zone_trip_update(struct thermal_zone_device *tz, int trip)
 		old_target = instance->target;
 		instance->target = get_target_state(instance, trend, throttle);
 
+		if (old_target == instance->target)
+			continue;
+
 		/* Activate a passive thermal instance */
 		if (old_target == THERMAL_NO_TARGET &&
 			instance->target != THERMAL_NO_TARGET)
-- 
1.7.9.5

[PATCH] thermal: step_wise: cdev only needs update on a new target state

[Eduardo Valentin]

Rui,

On 28-05-2013 02:55, Shawn Guo wrote:
> The cooling device only needs update on a new target state.  Since we
> already check old target in thermal_zone_trip_update(), we can do one
> more check to see if it's a new target state.  If not, we can reasonably
> save some uncecesary code execution.
> 

typo above:
s/uncecesary/unnecessary

> Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
> ---

A part from the above typo, I believe we must have this change in:

Acked-by: Eduardo Valentin <eduardo.valentin@ti.com>

>  drivers/thermal/step_wise.c |    3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/thermal/step_wise.c b/drivers/thermal/step_wise.c
> index 4d4ddae..0afbd86 100644
> --- a/drivers/thermal/step_wise.c
> +++ b/drivers/thermal/step_wise.c
> @@ -133,6 +133,9 @@ static void thermal_zone_trip_update(struct thermal_zone_device *tz, int trip)
>  		old_target = instance->target;
>  		instance->target = get_target_state(instance, trend, throttle);
>  
> +		if (old_target == instance->target)
> +			continue;
> +
>  		/* Activate a passive thermal instance */
>  		if (old_target == THERMAL_NO_TARGET &&
>  			instance->target != THERMAL_NO_TARGET)
> 


-- 
You have got to be excited about what you are doing. (L. Lamport)

Eduardo Valentin

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