diff options
Diffstat (limited to 'drivers/cpuidle/governors/menu.c')
| -rw-r--r-- | drivers/cpuidle/governors/menu.c | 50 |
1 files changed, 30 insertions, 20 deletions
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index 27fc733cb5b9..03d38c291de6 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -196,7 +196,7 @@ static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev); * of points is below a threshold. If it is... then use the * average of these 8 points as the estimated value. */ -static void get_typical_interval(struct menu_device *data) +static unsigned int get_typical_interval(struct menu_device *data) { int i, divisor; unsigned int max, thresh, avg; @@ -253,9 +253,7 @@ again: if (likely(variance <= U64_MAX/36)) { if ((((u64)avg*avg > variance*36) && (divisor * 4 >= INTERVALS * 3)) || variance <= 400) { - if (data->next_timer_us > avg) - data->predicted_us = avg; - return; + return avg; } } @@ -269,7 +267,7 @@ again: * with sporadic activity with a bunch of short pauses. */ if ((divisor * 4) <= INTERVALS * 3) - return; + return UINT_MAX; thresh = max - 1; goto again; @@ -286,6 +284,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) int latency_req = pm_qos_request(PM_QOS_CPU_DMA_LATENCY); int i; unsigned int interactivity_req; + unsigned int expected_interval; unsigned long nr_iowaiters, cpu_load; if (data->needs_update) { @@ -312,32 +311,43 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) data->correction_factor[data->bucket], RESOLUTION * DECAY); - get_typical_interval(data); - - /* - * Performance multiplier defines a minimum predicted idle - * duration / latency ratio. Adjust the latency limit if - * necessary. - */ - interactivity_req = data->predicted_us / performance_multiplier(nr_iowaiters, cpu_load); - if (latency_req > interactivity_req) - latency_req = interactivity_req; + expected_interval = get_typical_interval(data); + expected_interval = min(expected_interval, data->next_timer_us); if (CPUIDLE_DRIVER_STATE_START > 0) { - data->last_state_idx = CPUIDLE_DRIVER_STATE_START - 1; + struct cpuidle_state *s = &drv->states[CPUIDLE_DRIVER_STATE_START]; + unsigned int polling_threshold; + /* * We want to default to C1 (hlt), not to busy polling - * unless the timer is happening really really soon. + * unless the timer is happening really really soon, or + * C1's exit latency exceeds the user configured limit. */ - if (interactivity_req > 20 && - !drv->states[CPUIDLE_DRIVER_STATE_START].disabled && - dev->states_usage[CPUIDLE_DRIVER_STATE_START].disable == 0) + polling_threshold = max_t(unsigned int, 20, s->target_residency); + if (data->next_timer_us > polling_threshold && + latency_req > s->exit_latency && !s->disabled && + !dev->states_usage[CPUIDLE_DRIVER_STATE_START].disable) data->last_state_idx = CPUIDLE_DRIVER_STATE_START; + else + data->last_state_idx = CPUIDLE_DRIVER_STATE_START - 1; } else { data->last_state_idx = CPUIDLE_DRIVER_STATE_START; } /* + * Use the lowest expected idle interval to pick the idle state. + */ + data->predicted_us = min(data->predicted_us, expected_interval); + + /* + * 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); + if (latency_req > interactivity_req) + latency_req = interactivity_req; + + /* * Find the idle state with the lowest power while satisfying * our constraints. */ |