Merge back earlier cpuidle material for v5.5. (2c2a83d3) · Commits · EulixOS / Software / Kernel

drivers/cpuidle/governors/teo.c

+59 −19

Original line number	Diff line number	Diff line
		@@ -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;
		}

		if (idx < 0)
		/*
		* 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) {
		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.