diff --git a/drivers/cpuidle/governors/teo.c b/drivers/cpuidle/governors/teo.c index a2fd81067a13..4d7a60c5b24a 100644 --- a/drivers/cpuidle/governors/teo.c +++ b/drivers/cpuidle/governors/teo.c @@ -242,7 +242,7 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); int latency_req = cpuidle_governor_latency_req(dev->cpu); unsigned int duration_us, count; - int max_early_idx, idx, i; + int max_early_idx, constraint_idx, idx, i; ktime_t delta_tick; if (dev->last_state_idx >= 0) { @@ -257,6 +257,7 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, count = 0; max_early_idx = -1; + constraint_idx = drv->state_count; idx = -1; for (i = 0; i < drv->state_count; i++) { @@ -286,16 +287,8 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, if (s->target_residency > duration_us) break; - if (s->exit_latency > latency_req) { - /* - * If we break out of the loop for latency reasons, use - * the target residency of the selected state as the - * expected idle duration to avoid stopping the tick - * as long as that target residency is low enough. - */ - duration_us = drv->states[idx].target_residency; - goto refine; - } + if (s->exit_latency > latency_req && constraint_idx > i) + constraint_idx = i; idx = i; @@ -321,7 +314,13 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, duration_us = drv->states[idx].target_residency; } -refine: + /* + * If there is a latency constraint, it may be necessary to use a + * shallower idle state than the one selected so far. + */ + if (constraint_idx < idx) + idx = constraint_idx; + if (idx < 0) { idx = 0; /* No states enabled. Must use 0. */ } else if (idx > 0) { @@ -331,13 +330,12 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, /* * Count and sum the most recent idle duration values less than - * the target residency of the state selected so far, find the - * max. + * the current expected idle duration value. */ for (i = 0; i < INTERVALS; i++) { unsigned int val = cpu_data->intervals[i]; - if (val >= drv->states[idx].target_residency) + if (val >= duration_us) continue; count++; @@ -356,8 +354,10 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, * would be too shallow. */ if (!(tick_nohz_tick_stopped() && avg_us < TICK_USEC)) { - idx = teo_find_shallower_state(drv, dev, idx, avg_us); duration_us = avg_us; + if (drv->states[idx].target_residency > avg_us) + idx = teo_find_shallower_state(drv, dev, + idx, avg_us); } } }