lkml.org 
[lkml]   [2012]   [Nov]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC] cpuidle - remove the power_specified field in the driver
Hi,

On 11/12/2012 09:26 PM, Daniel Lezcano wrote:
> This patch follows the discussion about reinitializing the power usage
> when a C-state is added/removed.
>
> https://lkml.org/lkml/2012/10/16/518
>
> We realized the power usage field is never filled and when it is
> filled for tegra, the power_specified flag is not set making all these
> values to be resetted when the driver is initialized with the set_power_state
> function.
>
> Julius and I feel this is over-engineered and the power_specified
> flag could be simply removed and continue assuming the states are
> backward sorted.
>
> The menu governor select function is simplified as the power is ordered.
> Actually the condition is always true with the current code.
>
> The cpuidle_play_dead function is also simplified by doing a reverse lookup
> on the array.
>
> The set_power_states function is removed as it does no make sense anymore.
>
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> ---
> drivers/cpuidle/cpuidle.c | 17 ++++-------------
> drivers/cpuidle/driver.c | 25 -------------------------
> drivers/cpuidle/governors/menu.c | 8 ++------
> include/linux/cpuidle.h | 2 +-
> 4 files changed, 7 insertions(+), 45 deletions(-)
>
> diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
> index 711dd83..f983262 100644
> --- a/drivers/cpuidle/cpuidle.c
> +++ b/drivers/cpuidle/cpuidle.c
> @@ -69,24 +69,15 @@ int cpuidle_play_dead(void)
> {
> struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices);
> struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev);
> - int i, dead_state = -1;
> - int power_usage = -1;
> + int i;
>
> if (!drv)
> return -ENODEV;
>
> /* Find lowest-power state that supports long-term idle */
> - for (i = CPUIDLE_DRIVER_STATE_START; i < drv->state_count; i++) {
> - struct cpuidle_state *s = &drv->states[i];
> -
> - if (s->power_usage < power_usage && s->enter_dead) {
> - power_usage = s->power_usage;
> - dead_state = i;
> - }
> - }
> -
> - if (dead_state != -1)
> - return drv->states[dead_state].enter_dead(dev, dead_state);
> + for (i = drv->state_count; i >= CPUIDLE_DRIVER_STATE_START; i--)
> + if (drv->states[i].play_dead)

I guess you meant drv->states[i].enter_dead

> + return drv->states[i].enter_dead(dev, i);

--
Francesco


\
 
 \ /
  Last update: 2012-11-18 10:01    [W:0.067 / U:0.308 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site