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cpuidle: menu: Replace data->predicted_us with local variable

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The predicted_us field in struct menu_device is only accessed in
menu_select(), so replace it with a local variable in that function.

With that, stop using expected_interval instead of predicted_us to
store the new predicted idle duration value if it is set to the
selected state's target residency which is quite confusing.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
This commit is contained in:
Rafael J. Wysocki 2018-10-01 11:56:21 +02:00
parent 7037b43e00
commit 03dba27804
1 changed files with 11 additions and 12 deletions
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23
drivers/cpuidle/governors/menu.c
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@ -124,7 +124,6 @@ struct menu_device {
int tick_wakeup;
unsigned int next_timer_us;
unsigned int predicted_us;
unsigned int bucket;
unsigned int correction_factor[BUCKETS];
unsigned int intervals[INTERVALS];
@ -290,6 +289,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
int idx;
unsigned int interactivity_req;
unsigned int expected_interval;
unsigned int predicted_us;
unsigned long nr_iowaiters, cpu_load;
ktime_t delta_next;
@ -315,7 +315,7 @@ 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_ROUND_CLOSEST_ULL((uint64_t)data->next_timer_us *
predicted_us = DIV_ROUND_CLOSEST_ULL((uint64_t)data->next_timer_us *
data->correction_factor[data->bucket],
RESOLUTION * DECAY);
@ -341,7 +341,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
/*
* Use the lowest expected idle interval to pick the idle state.
*/
data->predicted_us = min(data->predicted_us, expected_interval);
predicted_us = min(predicted_us, expected_interval);
if (tick_nohz_tick_stopped()) {
/*
@ -352,19 +352,18 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
* the known time till the closest timer event for the idle
* state selection.
*/
if (data->predicted_us < TICK_USEC)
data->predicted_us = ktime_to_us(delta_next);
if (predicted_us < TICK_USEC)
predicted_us = ktime_to_us(delta_next);
} else {
/*
* Use the performance multiplier and the user-configurable
* latency_req to determine the maximum exit latency.
*/
interactivity_req = data->predicted_us / performance_multiplier(nr_iowaiters, cpu_load);
interactivity_req = predicted_us / performance_multiplier(nr_iowaiters, cpu_load);
if (latency_req > interactivity_req)
latency_req = interactivity_req;
}
expected_interval = data->predicted_us;
/*
* Find the idle state with the lowest power while satisfying
* our constraints.
@ -378,8 +377,8 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
continue;
if (idx == -1)
idx = i; /* first enabled state */
if (s->target_residency > data->predicted_us) {
if (data->predicted_us < TICK_USEC)
if (s->target_residency > predicted_us) {
if (predicted_us < TICK_USEC)
break;
if (!tick_nohz_tick_stopped()) {
@ -389,7 +388,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
* tick in that case and let the governor run
* again in the next iteration of the loop.
*/
expected_interval = drv->states[idx].target_residency;
predicted_us = drv->states[idx].target_residency;
break;
}
@ -412,7 +411,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
* expected idle duration so that the tick is retained
* as long as that target residency is low enough.
*/
expected_interval = drv->states[idx].target_residency;
predicted_us = drv->states[idx].target_residency;
break;
}
idx = i;
@ -426,7 +425,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
* expected idle duration is shorter than the tick period length.
*/
if (((drv->states[idx].flags & CPUIDLE_FLAG_POLLING) ||
expected_interval < TICK_USEC) && !tick_nohz_tick_stopped()) {
predicted_us < TICK_USEC) && !tick_nohz_tick_stopped()) {
unsigned int delta_next_us = ktime_to_us(delta_next);
*stop_tick = false;