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author | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2019-10-24 23:12:55 +0200 |
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committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2019-10-24 23:12:55 +0200 |
commit | 2c2a83d329b89c74063580bad95bcb595dc09535 (patch) | |
tree | 75603538c7e5527fa351ec49890771a08acbc1be /drivers/cpuidle | |
parent | 31d851407f90076c58291fb5eadc82c1dd613cee (diff) | |
parent | 159e48560f51d9c2aa02d762a18cd24f7868ab27 (diff) | |
download | linux-2c2a83d329b89c74063580bad95bcb595dc09535.tar.bz2 |
Merge back earlier cpuidle material for v5.5.
Diffstat (limited to 'drivers/cpuidle')
-rw-r--r-- | drivers/cpuidle/governors/teo.c | 78 |
1 files changed, 59 insertions, 19 deletions
diff --git a/drivers/cpuidle/governors/teo.c b/drivers/cpuidle/governors/teo.c index b5a0e498f798..b9b9156618e6 100644 --- a/drivers/cpuidle/governors/teo.c +++ b/drivers/cpuidle/governors/teo.c @@ -233,7 +233,7 @@ 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; + unsigned int duration_us, hits, misses, early_hits; int max_early_idx, constraint_idx, idx, i; ktime_t delta_tick; @@ -247,7 +247,9 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, cpu_data->sleep_length_ns = tick_nohz_get_sleep_length(&delta_tick); duration_us = ktime_to_us(cpu_data->sleep_length_ns); - count = 0; + hits = 0; + misses = 0; + early_hits = 0; max_early_idx = -1; constraint_idx = drv->state_count; idx = -1; @@ -258,23 +260,61 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, if (s->disabled || su->disable) { /* - * If the "early hits" metric of a disabled state is - * greater than the current maximum, it should be taken - * into account, because it would be a mistake to select - * a deeper state with lower "early hits" metric. The - * index cannot be changed to point to it, however, so - * just increase the max count alone and let the index - * still point to a shallower idle state. + * Ignore disabled states with target residencies beyond + * the anticipated idle duration. */ - if (max_early_idx >= 0 && - count < cpu_data->states[i].early_hits) - count = cpu_data->states[i].early_hits; + if (s->target_residency > duration_us) + continue; + + /* + * This state is disabled, so the range of idle duration + * values corresponding to it is covered by the current + * candidate state, but still the "hits" and "misses" + * metrics of the disabled state need to be used to + * decide whether or not the state covering the range in + * question is good enough. + */ + hits = cpu_data->states[i].hits; + misses = cpu_data->states[i].misses; + + if (early_hits >= cpu_data->states[i].early_hits || + idx < 0) + continue; + + /* + * If the current candidate state has been the one with + * the maximum "early hits" metric so far, the "early + * hits" metric of the disabled state replaces the + * current "early hits" count to avoid selecting a + * deeper state with lower "early hits" metric. + */ + if (max_early_idx == idx) { + early_hits = cpu_data->states[i].early_hits; + continue; + } + + /* + * The current candidate state is closer to the disabled + * one than the current maximum "early hits" state, so + * replace the latter with it, but in case the maximum + * "early hits" state index has not been set so far, + * check if the current candidate state is not too + * shallow for that role. + */ + if (!(tick_nohz_tick_stopped() && + drv->states[idx].target_residency < TICK_USEC)) { + early_hits = cpu_data->states[i].early_hits; + max_early_idx = idx; + } continue; } - if (idx < 0) + if (idx < 0) { idx = i; /* first enabled state */ + hits = cpu_data->states[i].hits; + misses = cpu_data->states[i].misses; + } if (s->target_residency > duration_us) break; @@ -283,11 +323,13 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, constraint_idx = i; idx = i; + hits = cpu_data->states[i].hits; + misses = cpu_data->states[i].misses; - if (count < cpu_data->states[i].early_hits && + if (early_hits < cpu_data->states[i].early_hits && !(tick_nohz_tick_stopped() && drv->states[i].target_residency < TICK_USEC)) { - count = cpu_data->states[i].early_hits; + early_hits = cpu_data->states[i].early_hits; max_early_idx = i; } } @@ -300,8 +342,7 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, * "early hits" metric, but if that cannot be determined, just use the * state selected so far. */ - if (cpu_data->states[idx].hits <= cpu_data->states[idx].misses && - max_early_idx >= 0) { + if (hits <= misses && max_early_idx >= 0) { idx = max_early_idx; duration_us = drv->states[idx].target_residency; } @@ -316,10 +357,9 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, if (idx < 0) { idx = 0; /* No states enabled. Must use 0. */ } else if (idx > 0) { + unsigned int count = 0; u64 sum = 0; - count = 0; - /* * Count and sum the most recent idle duration values less than * the current expected idle duration value. |