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cpuidle: rename expected_us to next_timer_us in menu governor

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The field expected_us is used to store the time remaining until next
timer expiry. The name is inaccurate, as we really do not expect all
wakeups to be caused by timers. In addition, another field with a very
similar name (predicted_us) is used to store the predicted time
remaining until any wakeup source being active.

This patch renames expected_us to next_timer_us in order to better
reflect the contained information.

Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
tuukka.tikkanen@linaro.org 2014-02-24 08:29:31 +02:00 committed by Rafael J. Wysocki
parent cfbf8d4857
commit 5dc2f5a303
1 changed files with 9 additions and 9 deletions
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18
drivers/cpuidle/governors/menu.c
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@ -122,7 +122,7 @@ struct menu_device {
int last_state_idx;
int needs_update;
unsigned int expected_us;
unsigned int next_timer_us;
unsigned int predicted_us;
unsigned int exit_us;
unsigned int bucket;
@ -257,7 +257,7 @@ again:
stddev = int_sqrt(stddev);
if (((avg > stddev * 6) && (divisor * 4 >= INTERVALS * 3))
|| stddev <= 20) {
if (data->expected_us > avg)
if (data->next_timer_us > avg)
data->predicted_us = avg;
return;
}
@ -306,11 +306,11 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
/* determine the expected residency time, round up */
t = ktime_to_timespec(tick_nohz_get_sleep_length());
data->expected_us =
data->next_timer_us =
t.tv_sec * USEC_PER_SEC + t.tv_nsec / NSEC_PER_USEC;
data->bucket = which_bucket(data->expected_us);
data->bucket = which_bucket(data->next_timer_us);
multiplier = performance_multiplier();
@ -326,7 +326,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
* operands are 32 bits.
* Make sure to round up for half microseconds.
*/
data->predicted_us = div_round64((uint64_t)data->expected_us *
data->predicted_us = div_round64((uint64_t)data->next_timer_us *
data->correction_factor[data->bucket],
RESOLUTION * DECAY);
@ -336,7 +336,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
* We want to default to C1 (hlt), not to busy polling
* unless the timer is happening really really soon.
*/
if (data->expected_us > 5 &&
if (data->next_timer_us > 5 &&
!drv->states[CPUIDLE_DRIVER_STATE_START].disabled &&
dev->states_usage[CPUIDLE_DRIVER_STATE_START].disable == 0)
data->last_state_idx = CPUIDLE_DRIVER_STATE_START;
@ -401,7 +401,7 @@ static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev)
* for the whole expected time.
*/
if (unlikely(!(target->flags & CPUIDLE_FLAG_TIME_VALID)))
last_idle_us = data->expected_us;
last_idle_us = data->next_timer_us;
measured_us = last_idle_us;
@ -418,8 +418,8 @@ static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev)
new_factor = data->correction_factor[data->bucket];
new_factor -= new_factor / DECAY;
if (data->expected_us > 0 && measured_us < MAX_INTERESTING)
new_factor += RESOLUTION * measured_us / data->expected_us;
if (data->next_timer_us > 0 && measured_us < MAX_INTERESTING)
new_factor += RESOLUTION * measured_us / data->next_timer_us;
else
/*
* we were idle so long that we count it as a perfect