1 // SPDX-License-Identifier: GPL-2.0
3 * CPUFreq governor based on scheduler-provided CPU utilization data.
5 * Copyright (C) 2016, Intel Corporation
6 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
9 #define IOWAIT_BOOST_MIN (SCHED_CAPACITY_SCALE / 8)
11 struct sugov_tunables {
12 struct gov_attr_set attr_set;
13 unsigned int rate_limit_us;
17 struct cpufreq_policy *policy;
19 struct sugov_tunables *tunables;
20 struct list_head tunables_hook;
22 raw_spinlock_t update_lock;
23 u64 last_freq_update_time;
24 s64 freq_update_delay_ns;
25 unsigned int next_freq;
26 unsigned int cached_raw_freq;
28 /* The next fields are only needed if fast switch cannot be used: */
29 struct irq_work irq_work;
30 struct kthread_work work;
31 struct mutex work_lock;
32 struct kthread_worker worker;
33 struct task_struct *thread;
34 bool work_in_progress;
37 bool need_freq_update;
41 struct update_util_data update_util;
42 struct sugov_policy *sg_policy;
45 bool iowait_boost_pending;
46 unsigned int iowait_boost;
53 /* The field below is for single-CPU policies only: */
54 #ifdef CONFIG_NO_HZ_COMMON
55 unsigned long saved_idle_calls;
59 static DEFINE_PER_CPU(struct sugov_cpu, sugov_cpu);
61 /************************ Governor internals ***********************/
63 static bool sugov_should_update_freq(struct sugov_policy *sg_policy, u64 time)
68 * Since cpufreq_update_util() is called with rq->lock held for
69 * the @target_cpu, our per-CPU data is fully serialized.
71 * However, drivers cannot in general deal with cross-CPU
72 * requests, so while get_next_freq() will work, our
73 * sugov_update_commit() call may not for the fast switching platforms.
75 * Hence stop here for remote requests if they aren't supported
76 * by the hardware, as calculating the frequency is pointless if
77 * we cannot in fact act on it.
79 * This is needed on the slow switching platforms too to prevent CPUs
80 * going offline from leaving stale IRQ work items behind.
82 if (!cpufreq_this_cpu_can_update(sg_policy->policy))
85 if (unlikely(sg_policy->limits_changed)) {
86 sg_policy->limits_changed = false;
87 sg_policy->need_freq_update = true;
91 delta_ns = time - sg_policy->last_freq_update_time;
93 return delta_ns >= sg_policy->freq_update_delay_ns;
96 static bool sugov_update_next_freq(struct sugov_policy *sg_policy, u64 time,
97 unsigned int next_freq)
99 if (sg_policy->need_freq_update)
100 sg_policy->need_freq_update = cpufreq_driver_test_flags(CPUFREQ_NEED_UPDATE_LIMITS);
101 else if (sg_policy->next_freq == next_freq)
104 sg_policy->next_freq = next_freq;
105 sg_policy->last_freq_update_time = time;
110 static void sugov_deferred_update(struct sugov_policy *sg_policy)
112 if (!sg_policy->work_in_progress) {
113 sg_policy->work_in_progress = true;
114 irq_work_queue(&sg_policy->irq_work);
119 * get_next_freq - Compute a new frequency for a given cpufreq policy.
120 * @sg_policy: schedutil policy object to compute the new frequency for.
121 * @util: Current CPU utilization.
122 * @max: CPU capacity.
124 * If the utilization is frequency-invariant, choose the new frequency to be
125 * proportional to it, that is
127 * next_freq = C * max_freq * util / max
129 * Otherwise, approximate the would-be frequency-invariant utilization by
130 * util_raw * (curr_freq / max_freq) which leads to
132 * next_freq = C * curr_freq * util_raw / max
134 * Take C = 1.25 for the frequency tipping point at (util / max) = 0.8.
136 * The lowest driver-supported frequency which is equal or greater than the raw
137 * next_freq (as calculated above) is returned, subject to policy min/max and
138 * cpufreq driver limitations.
140 static unsigned int get_next_freq(struct sugov_policy *sg_policy,
141 unsigned long util, unsigned long max)
143 struct cpufreq_policy *policy = sg_policy->policy;
144 unsigned int freq = arch_scale_freq_invariant() ?
145 policy->cpuinfo.max_freq : policy->cur;
147 util = map_util_perf(util);
148 freq = map_util_freq(util, freq, max);
150 if (freq == sg_policy->cached_raw_freq && !sg_policy->need_freq_update)
151 return sg_policy->next_freq;
153 sg_policy->cached_raw_freq = freq;
154 return cpufreq_driver_resolve_freq(policy, freq);
157 static void sugov_get_util(struct sugov_cpu *sg_cpu)
159 struct rq *rq = cpu_rq(sg_cpu->cpu);
160 unsigned long max = arch_scale_cpu_capacity(sg_cpu->cpu);
163 sg_cpu->bw_dl = cpu_bw_dl(rq);
164 sg_cpu->util = effective_cpu_util(sg_cpu->cpu, cpu_util_cfs(sg_cpu->cpu), max,
165 FREQUENCY_UTIL, NULL);
169 * sugov_iowait_reset() - Reset the IO boost status of a CPU.
170 * @sg_cpu: the sugov data for the CPU to boost
171 * @time: the update time from the caller
172 * @set_iowait_boost: true if an IO boost has been requested
174 * The IO wait boost of a task is disabled after a tick since the last update
175 * of a CPU. If a new IO wait boost is requested after more then a tick, then
176 * we enable the boost starting from IOWAIT_BOOST_MIN, which improves energy
177 * efficiency by ignoring sporadic wakeups from IO.
179 static bool sugov_iowait_reset(struct sugov_cpu *sg_cpu, u64 time,
180 bool set_iowait_boost)
182 s64 delta_ns = time - sg_cpu->last_update;
184 /* Reset boost only if a tick has elapsed since last request */
185 if (delta_ns <= TICK_NSEC)
188 sg_cpu->iowait_boost = set_iowait_boost ? IOWAIT_BOOST_MIN : 0;
189 sg_cpu->iowait_boost_pending = set_iowait_boost;
195 * sugov_iowait_boost() - Updates the IO boost status of a CPU.
196 * @sg_cpu: the sugov data for the CPU to boost
197 * @time: the update time from the caller
198 * @flags: SCHED_CPUFREQ_IOWAIT if the task is waking up after an IO wait
200 * Each time a task wakes up after an IO operation, the CPU utilization can be
201 * boosted to a certain utilization which doubles at each "frequent and
202 * successive" wakeup from IO, ranging from IOWAIT_BOOST_MIN to the utilization
203 * of the maximum OPP.
205 * To keep doubling, an IO boost has to be requested at least once per tick,
206 * otherwise we restart from the utilization of the minimum OPP.
208 static void sugov_iowait_boost(struct sugov_cpu *sg_cpu, u64 time,
211 bool set_iowait_boost = flags & SCHED_CPUFREQ_IOWAIT;
213 /* Reset boost if the CPU appears to have been idle enough */
214 if (sg_cpu->iowait_boost &&
215 sugov_iowait_reset(sg_cpu, time, set_iowait_boost))
218 /* Boost only tasks waking up after IO */
219 if (!set_iowait_boost)
222 /* Ensure boost doubles only one time at each request */
223 if (sg_cpu->iowait_boost_pending)
225 sg_cpu->iowait_boost_pending = true;
227 /* Double the boost at each request */
228 if (sg_cpu->iowait_boost) {
229 sg_cpu->iowait_boost =
230 min_t(unsigned int, sg_cpu->iowait_boost << 1, SCHED_CAPACITY_SCALE);
234 /* First wakeup after IO: start with minimum boost */
235 sg_cpu->iowait_boost = IOWAIT_BOOST_MIN;
239 * sugov_iowait_apply() - Apply the IO boost to a CPU.
240 * @sg_cpu: the sugov data for the cpu to boost
241 * @time: the update time from the caller
243 * A CPU running a task which woken up after an IO operation can have its
244 * utilization boosted to speed up the completion of those IO operations.
245 * The IO boost value is increased each time a task wakes up from IO, in
246 * sugov_iowait_apply(), and it's instead decreased by this function,
247 * each time an increase has not been requested (!iowait_boost_pending).
249 * A CPU which also appears to have been idle for at least one tick has also
250 * its IO boost utilization reset.
252 * This mechanism is designed to boost high frequently IO waiting tasks, while
253 * being more conservative on tasks which does sporadic IO operations.
255 static void sugov_iowait_apply(struct sugov_cpu *sg_cpu, u64 time)
259 /* No boost currently required */
260 if (!sg_cpu->iowait_boost)
263 /* Reset boost if the CPU appears to have been idle enough */
264 if (sugov_iowait_reset(sg_cpu, time, false))
267 if (!sg_cpu->iowait_boost_pending) {
269 * No boost pending; reduce the boost value.
271 sg_cpu->iowait_boost >>= 1;
272 if (sg_cpu->iowait_boost < IOWAIT_BOOST_MIN) {
273 sg_cpu->iowait_boost = 0;
278 sg_cpu->iowait_boost_pending = false;
281 * sg_cpu->util is already in capacity scale; convert iowait_boost
282 * into the same scale so we can compare.
284 boost = (sg_cpu->iowait_boost * sg_cpu->max) >> SCHED_CAPACITY_SHIFT;
285 boost = uclamp_rq_util_with(cpu_rq(sg_cpu->cpu), boost, NULL);
286 if (sg_cpu->util < boost)
287 sg_cpu->util = boost;
290 #ifdef CONFIG_NO_HZ_COMMON
291 static bool sugov_cpu_is_busy(struct sugov_cpu *sg_cpu)
293 unsigned long idle_calls = tick_nohz_get_idle_calls_cpu(sg_cpu->cpu);
294 bool ret = idle_calls == sg_cpu->saved_idle_calls;
296 sg_cpu->saved_idle_calls = idle_calls;
300 static inline bool sugov_cpu_is_busy(struct sugov_cpu *sg_cpu) { return false; }
301 #endif /* CONFIG_NO_HZ_COMMON */
304 * Make sugov_should_update_freq() ignore the rate limit when DL
305 * has increased the utilization.
307 static inline void ignore_dl_rate_limit(struct sugov_cpu *sg_cpu)
309 if (cpu_bw_dl(cpu_rq(sg_cpu->cpu)) > sg_cpu->bw_dl)
310 sg_cpu->sg_policy->limits_changed = true;
313 static inline bool sugov_update_single_common(struct sugov_cpu *sg_cpu,
314 u64 time, unsigned int flags)
316 sugov_iowait_boost(sg_cpu, time, flags);
317 sg_cpu->last_update = time;
319 ignore_dl_rate_limit(sg_cpu);
321 if (!sugov_should_update_freq(sg_cpu->sg_policy, time))
324 sugov_get_util(sg_cpu);
325 sugov_iowait_apply(sg_cpu, time);
330 static void sugov_update_single_freq(struct update_util_data *hook, u64 time,
333 struct sugov_cpu *sg_cpu = container_of(hook, struct sugov_cpu, update_util);
334 struct sugov_policy *sg_policy = sg_cpu->sg_policy;
335 unsigned int cached_freq = sg_policy->cached_raw_freq;
338 if (!sugov_update_single_common(sg_cpu, time, flags))
341 next_f = get_next_freq(sg_policy, sg_cpu->util, sg_cpu->max);
343 * Do not reduce the frequency if the CPU has not been idle
344 * recently, as the reduction is likely to be premature then.
346 * Except when the rq is capped by uclamp_max.
348 if (!uclamp_rq_is_capped(cpu_rq(sg_cpu->cpu)) &&
349 sugov_cpu_is_busy(sg_cpu) && next_f < sg_policy->next_freq) {
350 next_f = sg_policy->next_freq;
352 /* Restore cached freq as next_freq has changed */
353 sg_policy->cached_raw_freq = cached_freq;
356 if (!sugov_update_next_freq(sg_policy, time, next_f))
360 * This code runs under rq->lock for the target CPU, so it won't run
361 * concurrently on two different CPUs for the same target and it is not
362 * necessary to acquire the lock in the fast switch case.
364 if (sg_policy->policy->fast_switch_enabled) {
365 cpufreq_driver_fast_switch(sg_policy->policy, next_f);
367 raw_spin_lock(&sg_policy->update_lock);
368 sugov_deferred_update(sg_policy);
369 raw_spin_unlock(&sg_policy->update_lock);
373 static void sugov_update_single_perf(struct update_util_data *hook, u64 time,
376 struct sugov_cpu *sg_cpu = container_of(hook, struct sugov_cpu, update_util);
377 unsigned long prev_util = sg_cpu->util;
380 * Fall back to the "frequency" path if frequency invariance is not
381 * supported, because the direct mapping between the utilization and
382 * the performance levels depends on the frequency invariance.
384 if (!arch_scale_freq_invariant()) {
385 sugov_update_single_freq(hook, time, flags);
389 if (!sugov_update_single_common(sg_cpu, time, flags))
393 * Do not reduce the target performance level if the CPU has not been
394 * idle recently, as the reduction is likely to be premature then.
396 * Except when the rq is capped by uclamp_max.
398 if (!uclamp_rq_is_capped(cpu_rq(sg_cpu->cpu)) &&
399 sugov_cpu_is_busy(sg_cpu) && sg_cpu->util < prev_util)
400 sg_cpu->util = prev_util;
402 cpufreq_driver_adjust_perf(sg_cpu->cpu, map_util_perf(sg_cpu->bw_dl),
403 map_util_perf(sg_cpu->util), sg_cpu->max);
405 sg_cpu->sg_policy->last_freq_update_time = time;
408 static unsigned int sugov_next_freq_shared(struct sugov_cpu *sg_cpu, u64 time)
410 struct sugov_policy *sg_policy = sg_cpu->sg_policy;
411 struct cpufreq_policy *policy = sg_policy->policy;
412 unsigned long util = 0, max = 1;
415 for_each_cpu(j, policy->cpus) {
416 struct sugov_cpu *j_sg_cpu = &per_cpu(sugov_cpu, j);
417 unsigned long j_util, j_max;
419 sugov_get_util(j_sg_cpu);
420 sugov_iowait_apply(j_sg_cpu, time);
421 j_util = j_sg_cpu->util;
422 j_max = j_sg_cpu->max;
424 if (j_util * max > j_max * util) {
430 return get_next_freq(sg_policy, util, max);
434 sugov_update_shared(struct update_util_data *hook, u64 time, unsigned int flags)
436 struct sugov_cpu *sg_cpu = container_of(hook, struct sugov_cpu, update_util);
437 struct sugov_policy *sg_policy = sg_cpu->sg_policy;
440 raw_spin_lock(&sg_policy->update_lock);
442 sugov_iowait_boost(sg_cpu, time, flags);
443 sg_cpu->last_update = time;
445 ignore_dl_rate_limit(sg_cpu);
447 if (sugov_should_update_freq(sg_policy, time)) {
448 next_f = sugov_next_freq_shared(sg_cpu, time);
450 if (!sugov_update_next_freq(sg_policy, time, next_f))
453 if (sg_policy->policy->fast_switch_enabled)
454 cpufreq_driver_fast_switch(sg_policy->policy, next_f);
456 sugov_deferred_update(sg_policy);
459 raw_spin_unlock(&sg_policy->update_lock);
462 static void sugov_work(struct kthread_work *work)
464 struct sugov_policy *sg_policy = container_of(work, struct sugov_policy, work);
469 * Hold sg_policy->update_lock shortly to handle the case where:
470 * in case sg_policy->next_freq is read here, and then updated by
471 * sugov_deferred_update() just before work_in_progress is set to false
472 * here, we may miss queueing the new update.
474 * Note: If a work was queued after the update_lock is released,
475 * sugov_work() will just be called again by kthread_work code; and the
476 * request will be proceed before the sugov thread sleeps.
478 raw_spin_lock_irqsave(&sg_policy->update_lock, flags);
479 freq = sg_policy->next_freq;
480 sg_policy->work_in_progress = false;
481 raw_spin_unlock_irqrestore(&sg_policy->update_lock, flags);
483 mutex_lock(&sg_policy->work_lock);
484 __cpufreq_driver_target(sg_policy->policy, freq, CPUFREQ_RELATION_L);
485 mutex_unlock(&sg_policy->work_lock);
488 static void sugov_irq_work(struct irq_work *irq_work)
490 struct sugov_policy *sg_policy;
492 sg_policy = container_of(irq_work, struct sugov_policy, irq_work);
494 kthread_queue_work(&sg_policy->worker, &sg_policy->work);
497 /************************** sysfs interface ************************/
499 static struct sugov_tunables *global_tunables;
500 static DEFINE_MUTEX(global_tunables_lock);
502 static inline struct sugov_tunables *to_sugov_tunables(struct gov_attr_set *attr_set)
504 return container_of(attr_set, struct sugov_tunables, attr_set);
507 static ssize_t rate_limit_us_show(struct gov_attr_set *attr_set, char *buf)
509 struct sugov_tunables *tunables = to_sugov_tunables(attr_set);
511 return sprintf(buf, "%u\n", tunables->rate_limit_us);
515 rate_limit_us_store(struct gov_attr_set *attr_set, const char *buf, size_t count)
517 struct sugov_tunables *tunables = to_sugov_tunables(attr_set);
518 struct sugov_policy *sg_policy;
519 unsigned int rate_limit_us;
521 if (kstrtouint(buf, 10, &rate_limit_us))
524 tunables->rate_limit_us = rate_limit_us;
526 list_for_each_entry(sg_policy, &attr_set->policy_list, tunables_hook)
527 sg_policy->freq_update_delay_ns = rate_limit_us * NSEC_PER_USEC;
532 static struct governor_attr rate_limit_us = __ATTR_RW(rate_limit_us);
534 static struct attribute *sugov_attrs[] = {
538 ATTRIBUTE_GROUPS(sugov);
540 static void sugov_tunables_free(struct kobject *kobj)
542 struct gov_attr_set *attr_set = to_gov_attr_set(kobj);
544 kfree(to_sugov_tunables(attr_set));
547 static struct kobj_type sugov_tunables_ktype = {
548 .default_groups = sugov_groups,
549 .sysfs_ops = &governor_sysfs_ops,
550 .release = &sugov_tunables_free,
553 /********************** cpufreq governor interface *********************/
555 struct cpufreq_governor schedutil_gov;
557 static struct sugov_policy *sugov_policy_alloc(struct cpufreq_policy *policy)
559 struct sugov_policy *sg_policy;
561 sg_policy = kzalloc(sizeof(*sg_policy), GFP_KERNEL);
565 sg_policy->policy = policy;
566 raw_spin_lock_init(&sg_policy->update_lock);
570 static void sugov_policy_free(struct sugov_policy *sg_policy)
575 static int sugov_kthread_create(struct sugov_policy *sg_policy)
577 struct task_struct *thread;
578 struct sched_attr attr = {
579 .size = sizeof(struct sched_attr),
580 .sched_policy = SCHED_DEADLINE,
581 .sched_flags = SCHED_FLAG_SUGOV,
585 * Fake (unused) bandwidth; workaround to "fix"
586 * priority inheritance.
588 .sched_runtime = 1000000,
589 .sched_deadline = 10000000,
590 .sched_period = 10000000,
592 struct cpufreq_policy *policy = sg_policy->policy;
595 /* kthread only required for slow path */
596 if (policy->fast_switch_enabled)
599 kthread_init_work(&sg_policy->work, sugov_work);
600 kthread_init_worker(&sg_policy->worker);
601 thread = kthread_create(kthread_worker_fn, &sg_policy->worker,
603 cpumask_first(policy->related_cpus));
604 if (IS_ERR(thread)) {
605 pr_err("failed to create sugov thread: %ld\n", PTR_ERR(thread));
606 return PTR_ERR(thread);
609 ret = sched_setattr_nocheck(thread, &attr);
611 kthread_stop(thread);
612 pr_warn("%s: failed to set SCHED_DEADLINE\n", __func__);
616 sg_policy->thread = thread;
617 kthread_bind_mask(thread, policy->related_cpus);
618 init_irq_work(&sg_policy->irq_work, sugov_irq_work);
619 mutex_init(&sg_policy->work_lock);
621 wake_up_process(thread);
626 static void sugov_kthread_stop(struct sugov_policy *sg_policy)
628 /* kthread only required for slow path */
629 if (sg_policy->policy->fast_switch_enabled)
632 kthread_flush_worker(&sg_policy->worker);
633 kthread_stop(sg_policy->thread);
634 mutex_destroy(&sg_policy->work_lock);
637 static struct sugov_tunables *sugov_tunables_alloc(struct sugov_policy *sg_policy)
639 struct sugov_tunables *tunables;
641 tunables = kzalloc(sizeof(*tunables), GFP_KERNEL);
643 gov_attr_set_init(&tunables->attr_set, &sg_policy->tunables_hook);
644 if (!have_governor_per_policy())
645 global_tunables = tunables;
650 static void sugov_clear_global_tunables(void)
652 if (!have_governor_per_policy())
653 global_tunables = NULL;
656 static int sugov_init(struct cpufreq_policy *policy)
658 struct sugov_policy *sg_policy;
659 struct sugov_tunables *tunables;
662 /* State should be equivalent to EXIT */
663 if (policy->governor_data)
666 cpufreq_enable_fast_switch(policy);
668 sg_policy = sugov_policy_alloc(policy);
671 goto disable_fast_switch;
674 ret = sugov_kthread_create(sg_policy);
678 mutex_lock(&global_tunables_lock);
680 if (global_tunables) {
681 if (WARN_ON(have_governor_per_policy())) {
685 policy->governor_data = sg_policy;
686 sg_policy->tunables = global_tunables;
688 gov_attr_set_get(&global_tunables->attr_set, &sg_policy->tunables_hook);
692 tunables = sugov_tunables_alloc(sg_policy);
698 tunables->rate_limit_us = cpufreq_policy_transition_delay_us(policy);
700 policy->governor_data = sg_policy;
701 sg_policy->tunables = tunables;
703 ret = kobject_init_and_add(&tunables->attr_set.kobj, &sugov_tunables_ktype,
704 get_governor_parent_kobj(policy), "%s",
710 mutex_unlock(&global_tunables_lock);
714 kobject_put(&tunables->attr_set.kobj);
715 policy->governor_data = NULL;
716 sugov_clear_global_tunables();
719 sugov_kthread_stop(sg_policy);
720 mutex_unlock(&global_tunables_lock);
723 sugov_policy_free(sg_policy);
726 cpufreq_disable_fast_switch(policy);
728 pr_err("initialization failed (error %d)\n", ret);
732 static void sugov_exit(struct cpufreq_policy *policy)
734 struct sugov_policy *sg_policy = policy->governor_data;
735 struct sugov_tunables *tunables = sg_policy->tunables;
738 mutex_lock(&global_tunables_lock);
740 count = gov_attr_set_put(&tunables->attr_set, &sg_policy->tunables_hook);
741 policy->governor_data = NULL;
743 sugov_clear_global_tunables();
745 mutex_unlock(&global_tunables_lock);
747 sugov_kthread_stop(sg_policy);
748 sugov_policy_free(sg_policy);
749 cpufreq_disable_fast_switch(policy);
752 static int sugov_start(struct cpufreq_policy *policy)
754 struct sugov_policy *sg_policy = policy->governor_data;
755 void (*uu)(struct update_util_data *data, u64 time, unsigned int flags);
758 sg_policy->freq_update_delay_ns = sg_policy->tunables->rate_limit_us * NSEC_PER_USEC;
759 sg_policy->last_freq_update_time = 0;
760 sg_policy->next_freq = 0;
761 sg_policy->work_in_progress = false;
762 sg_policy->limits_changed = false;
763 sg_policy->cached_raw_freq = 0;
765 sg_policy->need_freq_update = cpufreq_driver_test_flags(CPUFREQ_NEED_UPDATE_LIMITS);
767 for_each_cpu(cpu, policy->cpus) {
768 struct sugov_cpu *sg_cpu = &per_cpu(sugov_cpu, cpu);
770 memset(sg_cpu, 0, sizeof(*sg_cpu));
772 sg_cpu->sg_policy = sg_policy;
775 if (policy_is_shared(policy))
776 uu = sugov_update_shared;
777 else if (policy->fast_switch_enabled && cpufreq_driver_has_adjust_perf())
778 uu = sugov_update_single_perf;
780 uu = sugov_update_single_freq;
782 for_each_cpu(cpu, policy->cpus) {
783 struct sugov_cpu *sg_cpu = &per_cpu(sugov_cpu, cpu);
785 cpufreq_add_update_util_hook(cpu, &sg_cpu->update_util, uu);
790 static void sugov_stop(struct cpufreq_policy *policy)
792 struct sugov_policy *sg_policy = policy->governor_data;
795 for_each_cpu(cpu, policy->cpus)
796 cpufreq_remove_update_util_hook(cpu);
800 if (!policy->fast_switch_enabled) {
801 irq_work_sync(&sg_policy->irq_work);
802 kthread_cancel_work_sync(&sg_policy->work);
806 static void sugov_limits(struct cpufreq_policy *policy)
808 struct sugov_policy *sg_policy = policy->governor_data;
810 if (!policy->fast_switch_enabled) {
811 mutex_lock(&sg_policy->work_lock);
812 cpufreq_policy_apply_limits(policy);
813 mutex_unlock(&sg_policy->work_lock);
816 sg_policy->limits_changed = true;
819 struct cpufreq_governor schedutil_gov = {
821 .owner = THIS_MODULE,
822 .flags = CPUFREQ_GOV_DYNAMIC_SWITCHING,
825 .start = sugov_start,
827 .limits = sugov_limits,
830 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL
831 struct cpufreq_governor *cpufreq_default_governor(void)
833 return &schedutil_gov;
837 cpufreq_governor_init(schedutil_gov);
839 #ifdef CONFIG_ENERGY_MODEL
840 static void rebuild_sd_workfn(struct work_struct *work)
842 rebuild_sched_domains_energy();
844 static DECLARE_WORK(rebuild_sd_work, rebuild_sd_workfn);
847 * EAS shouldn't be attempted without sugov, so rebuild the sched_domains
848 * on governor changes to make sure the scheduler knows about it.
850 void sched_cpufreq_governor_change(struct cpufreq_policy *policy,
851 struct cpufreq_governor *old_gov)
853 if (old_gov == &schedutil_gov || policy->governor == &schedutil_gov) {
855 * When called from the cpufreq_register_driver() path, the
856 * cpu_hotplug_lock is already held, so use a work item to
857 * avoid nested locking in rebuild_sched_domains().
859 schedule_work(&rebuild_sd_work);