// SPDX-License-Identifier: GPL-2.0 /* * CPUFreq governor based on scheduler-provided CPU utilization data. * * Copyright (C) 2016, Intel Corporation * Author: Rafael J. Wysocki */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include "sched.h" #include #include #include static unsigned int default_efficient_freq[] = {0}; static u64 default_up_delay[] = {0}; struct sugov_tunables { struct gov_attr_set attr_set; unsigned int up_rate_limit_us; unsigned int down_rate_limit_us; unsigned int *efficient_freq; int nefficient_freq; u64 *up_delay; int nup_delay; int current_step; }; struct sugov_policy { struct cpufreq_policy *policy; struct sugov_tunables *tunables; struct list_head tunables_hook; raw_spinlock_t update_lock; /* For shared policies */ u64 last_freq_update_time; s64 min_rate_limit_ns; s64 up_rate_delay_ns; s64 down_rate_delay_ns; unsigned int next_freq; unsigned int cached_raw_freq; u64 first_hp_request_time; /* The next fields are only needed if fast switch cannot be used: */ struct irq_work irq_work; struct kthread_work work; struct mutex work_lock; struct kthread_worker worker; struct task_struct *thread; bool work_in_progress; bool limits_changed; bool need_freq_update; }; struct sugov_cpu { struct update_util_data update_util; struct sugov_policy *sg_policy; unsigned int cpu; u64 last_update; unsigned long bw_dl; unsigned long max; }; static DEFINE_PER_CPU(struct sugov_cpu, sugov_cpu); static inline int match_nearest_efficient_step(int freq, int maxstep, int *freq_table) { int i; for (i=0; i= freq) break; } return i; } static inline void do_freq_limit(struct sugov_policy *sg_policy, unsigned int *freq, u64 time) { if (*freq > sg_policy->tunables->efficient_freq[sg_policy->tunables->current_step] && !sg_policy->first_hp_request_time) { /* First request */ *freq = sg_policy->tunables->efficient_freq[sg_policy->tunables->current_step]; sg_policy->first_hp_request_time = time; return; } if (*freq < sg_policy->tunables->efficient_freq[sg_policy->tunables->current_step]) { /* It's already under current efficient frequency */ /* Goto a lower one */ sg_policy->tunables->current_step = match_nearest_efficient_step(*freq, sg_policy->tunables->nefficient_freq, sg_policy->tunables->efficient_freq); sg_policy->first_hp_request_time = 0; return; } if ((sg_policy->first_hp_request_time && time < sg_policy->first_hp_request_time + sg_policy->tunables->up_delay[sg_policy->tunables->current_step])){ /* Restrict it */ *freq = sg_policy->tunables->efficient_freq[sg_policy->tunables->current_step]; return; } if (sg_policy->tunables->current_step + 1 <= sg_policy->tunables->nefficient_freq - 1 && sg_policy->tunables->current_step + 1 <= sg_policy->tunables->nup_delay - 1) { /* Unlock a higher efficient frequency */ sg_policy->tunables->current_step++; sg_policy->first_hp_request_time = time; if (*freq > sg_policy->tunables->efficient_freq[sg_policy->tunables->current_step]) *freq = sg_policy->tunables->efficient_freq[sg_policy->tunables->current_step]; return; } } /************************ Governor internals ***********************/ static bool sugov_should_update_freq(struct sugov_policy *sg_policy, u64 time) { s64 delta_ns; /* * Since cpufreq_update_util() is called with rq->lock held for * the @target_cpu, our per-CPU data is fully serialized. * * However, drivers cannot in general deal with cross-CPU * requests, so while get_next_freq() will work, our * sugov_update_commit() call may not for the fast switching platforms. * * Hence stop here for remote requests if they aren't supported * by the hardware, as calculating the frequency is pointless if * we cannot in fact act on it. * * This is needed on the slow switching platforms too to prevent CPUs * going offline from leaving stale IRQ work items behind. */ if (!cpufreq_this_cpu_can_update(sg_policy->policy)) return false; if (unlikely(sg_policy->limits_changed)) { sg_policy->limits_changed = false; sg_policy->need_freq_update = true; return true; } /* If the last frequency wasn't set yet then we can still amend it */ if (sg_policy->work_in_progress) return true; /* No need to recalculate next freq for min_rate_limit_us * at least. However we might still decide to further rate * limit once frequency change direction is decided, according * to the separate rate limits. */ delta_ns = time - sg_policy->last_freq_update_time; return delta_ns >= sg_policy->min_rate_limit_ns; } static bool sugov_up_down_rate_limit(struct sugov_policy *sg_policy, u64 time, unsigned int next_freq) { s64 delta_ns; delta_ns = time - sg_policy->last_freq_update_time; if (next_freq > sg_policy->next_freq && delta_ns < sg_policy->up_rate_delay_ns) return true; if (next_freq < sg_policy->next_freq && delta_ns < sg_policy->down_rate_delay_ns) return true; return false; } static bool sugov_update_next_freq(struct sugov_policy *sg_policy, u64 time, unsigned int next_freq) { if (!sg_policy->need_freq_update) { if (sg_policy->next_freq == next_freq) return false; } else { sg_policy->need_freq_update = cpufreq_driver_test_flags(CPUFREQ_NEED_UPDATE_LIMITS); } if (sugov_up_down_rate_limit(sg_policy, time, next_freq)) return false; sg_policy->next_freq = next_freq; sg_policy->last_freq_update_time = time; return true; } static void sugov_fast_switch(struct sugov_policy *sg_policy, u64 time, unsigned int next_freq) { if (sugov_update_next_freq(sg_policy, time, next_freq)) cpufreq_driver_fast_switch(sg_policy->policy, next_freq); } static void sugov_deferred_update(struct sugov_policy *sg_policy, u64 time, unsigned int next_freq) { if (!sugov_update_next_freq(sg_policy, time, next_freq)) return; if (!sg_policy->work_in_progress) { sg_policy->work_in_progress = true; irq_work_queue(&sg_policy->irq_work); } } /** * get_next_freq - Compute a new frequency for a given cpufreq policy. * @sg_policy: schedhorizon policy object to compute the new frequency for. * @util: Current CPU utilization. * @max: CPU capacity. * * If the utilization is frequency-invariant, choose the new frequency to be * proportional to it, that is * * next_freq = C * max_freq * util / max * * Otherwise, approximate the would-be frequency-invariant utilization by * util_raw * (curr_freq / max_freq) which leads to * * next_freq = C * curr_freq * util_raw / max * * Take C = 1.25 for the frequency tipping point at (util / max) = 0.8. * * The lowest driver-supported frequency which is equal or greater than the raw * next_freq (as calculated above) is returned, subject to policy min/max and * cpufreq driver limitations. */ static unsigned int get_next_freq(struct sugov_policy *sg_policy, unsigned long util, unsigned long max, u64 time) { struct cpufreq_policy *policy = sg_policy->policy; unsigned int freq = arch_scale_freq_invariant() ? policy->cpuinfo.max_freq : policy->cur; unsigned int idx, l_freq, h_freq; unsigned long next_freq = 0; trace_android_vh_map_util_freq(util, freq, max, &next_freq, policy, &sg_policy->need_freq_update); if (next_freq) freq = next_freq; else freq = map_util_freq(util, freq, max); do_freq_limit(sg_policy, &freq, time); if (freq == sg_policy->cached_raw_freq && !sg_policy->need_freq_update) return sg_policy->next_freq; sg_policy->cached_raw_freq = freq; l_freq = cpufreq_driver_resolve_freq(policy, freq); idx = cpufreq_frequency_table_target(policy, freq, CPUFREQ_RELATION_H); h_freq = policy->freq_table[idx].frequency; h_freq = clamp(h_freq, policy->min, policy->max); if (l_freq <= h_freq || l_freq == policy->min) return l_freq; /* * Use the frequency step below if the calculated frequency is <20% * higher than it. */ if (mult_frac(100, freq - h_freq, l_freq - h_freq) < 20) return h_freq; return l_freq; } /* * This function computes an effective utilization for the given CPU, to be * used for frequency selection given the linear relation: f = u * f_max. * * The scheduler tracks the following metrics: * * cpu_util_{cfs,rt,dl,irq}() * cpu_bw_dl() * * Where the cfs,rt and dl util numbers are tracked with the same metric and * synchronized windows and are thus directly comparable. * * The cfs,rt,dl utilization are the running times measured with rq->clock_task * which excludes things like IRQ and steal-time. These latter are then accrued * in the irq utilization. * * The DL bandwidth number otoh is not a measured metric but a value computed * based on the task model parameters and gives the minimal utilization * required to meet deadlines. */ unsigned long schedhorizon_cpu_util(int cpu, unsigned long util_cfs, unsigned long max, enum schedutil_type type, struct task_struct *p) { unsigned long dl_util, util, irq; struct rq *rq = cpu_rq(cpu); if (!uclamp_is_used() && type == FREQUENCY_UTIL && rt_rq_is_runnable(&rq->rt)) { return max; } /* * Early check to see if IRQ/steal time saturates the CPU, can be * because of inaccuracies in how we track these -- see * update_irq_load_avg(). */ irq = cpu_util_irq(rq); if (unlikely(irq >= max)) return max; /* * Because the time spend on RT/DL tasks is visible as 'lost' time to * CFS tasks and we use the same metric to track the effective * utilization (PELT windows are synchronized) we can directly add them * to obtain the CPU's actual utilization. * * CFS and RT utilization can be boosted or capped, depending on * utilization clamp constraints requested by currently RUNNABLE * tasks. * When there are no CFS RUNNABLE tasks, clamps are released and * frequency will be gracefully reduced with the utilization decay. */ util = util_cfs + cpu_util_rt(rq); if (type == FREQUENCY_UTIL) util = uclamp_rq_util_with(rq, util, p); dl_util = cpu_util_dl(rq); /* * For frequency selection we do not make cpu_util_dl() a permanent part * of this sum because we want to use cpu_bw_dl() later on, but we need * to check if the CFS+RT+DL sum is saturated (ie. no idle time) such * that we select f_max when there is no idle time. * * NOTE: numerical errors or stop class might cause us to not quite hit * saturation when we should -- something for later. */ if (util + dl_util >= max) return max; /* * OTOH, for energy computation we need the estimated running time, so * include util_dl and ignore dl_bw. */ if (type == ENERGY_UTIL) util += dl_util; /* * There is still idle time; further improve the number by using the * irq metric. Because IRQ/steal time is hidden from the task clock we * need to scale the task numbers: * * max - irq * U' = irq + --------- * U * max */ util = scale_irq_capacity(util, irq, max); util += irq; /* * Bandwidth required by DEADLINE must always be granted while, for * FAIR and RT, we use blocked utilization of IDLE CPUs as a mechanism * to gracefully reduce the frequency when no tasks show up for longer * periods of time. * * Ideally we would like to set bw_dl as min/guaranteed freq and util + * bw_dl as requested freq. However, cpufreq is not yet ready for such * an interface. So, we only do the latter for now. */ if (type == FREQUENCY_UTIL) util += cpu_bw_dl(rq); return min(max, util); } EXPORT_SYMBOL_GPL(schedhorizon_cpu_util); static unsigned long sugov_get_util(struct sugov_cpu *sg_cpu) { struct rq *rq = cpu_rq(sg_cpu->cpu); unsigned long util = cpu_util_cfs(rq); unsigned long max = arch_scale_cpu_capacity(sg_cpu->cpu); sg_cpu->max = max; sg_cpu->bw_dl = cpu_bw_dl(rq); return schedhorizon_cpu_util(sg_cpu->cpu, util, max, FREQUENCY_UTIL, NULL); } /* * Make sugov_should_update_freq() ignore the rate limit when DL * has increased the utilization. */ static inline void ignore_dl_rate_limit(struct sugov_cpu *sg_cpu, struct sugov_policy *sg_policy) { if (cpu_bw_dl(cpu_rq(sg_cpu->cpu)) > sg_cpu->bw_dl) sg_policy->limits_changed = true; } static void sugov_update_single(struct update_util_data *hook, u64 time, unsigned int flags) { struct sugov_cpu *sg_cpu = container_of(hook, struct sugov_cpu, update_util); struct sugov_policy *sg_policy = sg_cpu->sg_policy; unsigned long util, max; unsigned int next_f; sg_cpu->last_update = time; ignore_dl_rate_limit(sg_cpu, sg_policy); if (!sugov_should_update_freq(sg_policy, time)) return; util = sugov_get_util(sg_cpu); max = sg_cpu->max; next_f = get_next_freq(sg_policy, util, max, time); /* * This code runs under rq->lock for the target CPU, so it won't run * concurrently on two different CPUs for the same target and it is not * necessary to acquire the lock in the fast switch case. */ if (sg_policy->policy->fast_switch_enabled) { sugov_fast_switch(sg_policy, time, next_f); } else { raw_spin_lock(&sg_policy->update_lock); sugov_deferred_update(sg_policy, time, next_f); raw_spin_unlock(&sg_policy->update_lock); } } static unsigned int sugov_next_freq_shared(struct sugov_cpu *sg_cpu, u64 time) { struct sugov_policy *sg_policy = sg_cpu->sg_policy; struct cpufreq_policy *policy = sg_policy->policy; unsigned long util = 0, max = 1; unsigned int j; for_each_cpu(j, policy->cpus) { struct sugov_cpu *j_sg_cpu = &per_cpu(sugov_cpu, j); unsigned long j_util, j_max; j_util = sugov_get_util(j_sg_cpu); j_max = j_sg_cpu->max; if (j_util * max > j_max * util) { util = j_util; max = j_max; } } return get_next_freq(sg_policy, util, max, time); } static void sugov_update_shared(struct update_util_data *hook, u64 time, unsigned int flags) { struct sugov_cpu *sg_cpu = container_of(hook, struct sugov_cpu, update_util); struct sugov_policy *sg_policy = sg_cpu->sg_policy; unsigned int next_f; raw_spin_lock(&sg_policy->update_lock); sg_cpu->last_update = time; ignore_dl_rate_limit(sg_cpu, sg_policy); if (sugov_should_update_freq(sg_policy, time)) { next_f = sugov_next_freq_shared(sg_cpu, time); if (sg_policy->policy->fast_switch_enabled) sugov_fast_switch(sg_policy, time, next_f); else sugov_deferred_update(sg_policy, time, next_f); } raw_spin_unlock(&sg_policy->update_lock); } static void sugov_work(struct kthread_work *work) { struct sugov_policy *sg_policy = container_of(work, struct sugov_policy, work); unsigned int freq; unsigned long flags; /* * Hold sg_policy->update_lock shortly to handle the case where: * incase sg_policy->next_freq is read here, and then updated by * sugov_deferred_update() just before work_in_progress is set to false * here, we may miss queueing the new update. * * Note: If a work was queued after the update_lock is released, * sugov_work() will just be called again by kthread_work code; and the * request will be proceed before the sugov thread sleeps. */ raw_spin_lock_irqsave(&sg_policy->update_lock, flags); freq = sg_policy->next_freq; sg_policy->work_in_progress = false; raw_spin_unlock_irqrestore(&sg_policy->update_lock, flags); mutex_lock(&sg_policy->work_lock); __cpufreq_driver_target(sg_policy->policy, freq, CPUFREQ_RELATION_L); mutex_unlock(&sg_policy->work_lock); } static void sugov_irq_work(struct irq_work *irq_work) { struct sugov_policy *sg_policy; sg_policy = container_of(irq_work, struct sugov_policy, irq_work); kthread_queue_work(&sg_policy->worker, &sg_policy->work); } static unsigned int *resolve_data_freq (const char *buf, int *num_ret,size_t count) { const char *cp; unsigned int *output; int num = 1, i; cp = buf; while ((cp = strpbrk(cp + 1, " "))) num++; output = kmalloc(num * sizeof(unsigned int), GFP_KERNEL); cp = buf; i = 0; while (i < num && cp-bufmin_rate_limit_ns = min(sg_policy->up_rate_delay_ns, sg_policy->down_rate_delay_ns); mutex_unlock(&min_rate_lock); } static ssize_t up_rate_limit_us_show(struct gov_attr_set *attr_set, char *buf) { struct sugov_tunables *tunables = to_sugov_tunables(attr_set); return sprintf(buf, "%u\n", tunables->up_rate_limit_us); } static ssize_t down_rate_limit_us_show(struct gov_attr_set *attr_set, char *buf) { struct sugov_tunables *tunables = to_sugov_tunables(attr_set); return sprintf(buf, "%u\n", tunables->down_rate_limit_us); } static ssize_t up_rate_limit_us_store(struct gov_attr_set *attr_set, const char *buf, size_t count) { struct sugov_tunables *tunables = to_sugov_tunables(attr_set); struct sugov_policy *sg_policy; unsigned int rate_limit_us; if (kstrtouint(buf, 10, &rate_limit_us)) return -EINVAL; tunables->up_rate_limit_us = rate_limit_us; list_for_each_entry(sg_policy, &attr_set->policy_list, tunables_hook) { sg_policy->up_rate_delay_ns = rate_limit_us * NSEC_PER_USEC; update_min_rate_limit_ns(sg_policy); } return count; } static ssize_t down_rate_limit_us_store(struct gov_attr_set *attr_set, const char *buf, size_t count) { struct sugov_tunables *tunables = to_sugov_tunables(attr_set); struct sugov_policy *sg_policy; unsigned int rate_limit_us; if (kstrtouint(buf, 10, &rate_limit_us)) return -EINVAL; tunables->down_rate_limit_us = rate_limit_us; list_for_each_entry(sg_policy, &attr_set->policy_list, tunables_hook) { sg_policy->down_rate_delay_ns = rate_limit_us * NSEC_PER_USEC; update_min_rate_limit_ns(sg_policy); } return count; } static ssize_t efficient_freq_show(struct gov_attr_set *attr_set, char *buf) { struct sugov_tunables *tunables = to_sugov_tunables(attr_set); int i; ssize_t ret = 0; for (i = 0; i < tunables->nefficient_freq; i++) ret += sprintf(buf + ret, "%llu%s", tunables->efficient_freq[i], " "); sprintf(buf + ret - 1, "\n"); return ret; } static ssize_t up_delay_show(struct gov_attr_set *attr_set, char *buf) { struct sugov_tunables *tunables = to_sugov_tunables(attr_set); int i; ssize_t ret = 0; for (i = 0; i < tunables->nup_delay; i++) ret += sprintf(buf + ret, "%u%s", tunables->up_delay[i] / NSEC_PER_MSEC, " "); sprintf(buf + ret - 1, "\n"); return ret; } static ssize_t efficient_freq_store(struct gov_attr_set *attr_set, const char *buf, size_t count) { struct sugov_tunables *tunables = to_sugov_tunables(attr_set); int new_num; unsigned int *new_efficient_freq = NULL, *old; new_efficient_freq = resolve_data_freq(buf, &new_num, count); if (new_efficient_freq) { old = tunables->efficient_freq; tunables->efficient_freq = new_efficient_freq; tunables->nefficient_freq = new_num; tunables->current_step = 0; if (old != default_efficient_freq) kfree(old); } return count; } static ssize_t up_delay_store(struct gov_attr_set *attr_set, const char *buf, size_t count) { struct sugov_tunables *tunables = to_sugov_tunables(attr_set); int new_num; u64 *new_up_delay = NULL, *old; new_up_delay = resolve_data_delay(buf, &new_num, count); if (new_up_delay) { old = tunables->up_delay; tunables->up_delay = new_up_delay; tunables->nup_delay = new_num; tunables->current_step = 0; if (old != default_up_delay) kfree(old); } return count; } static struct governor_attr up_rate_limit_us = __ATTR_RW(up_rate_limit_us); static struct governor_attr down_rate_limit_us = __ATTR_RW(down_rate_limit_us); static struct governor_attr efficient_freq = __ATTR_RW(efficient_freq); static struct governor_attr up_delay = __ATTR_RW(up_delay); static struct attribute *sugov_attrs[] = { &up_rate_limit_us.attr, &down_rate_limit_us.attr, &efficient_freq.attr, &up_delay.attr, NULL }; ATTRIBUTE_GROUPS(sugov); static void sugov_tunables_free(struct kobject *kobj) { struct gov_attr_set *attr_set = container_of(kobj, struct gov_attr_set, kobj); kfree(to_sugov_tunables(attr_set)); } static struct kobj_type sugov_tunables_ktype = { .default_groups = sugov_groups, .sysfs_ops = &governor_sysfs_ops, .release = &sugov_tunables_free, }; /********************** cpufreq governor interface *********************/ struct cpufreq_governor schedhorizon_gov; static struct sugov_policy *sugov_policy_alloc(struct cpufreq_policy *policy) { struct sugov_policy *sg_policy; sg_policy = kzalloc(sizeof(*sg_policy), GFP_KERNEL); if (!sg_policy) return NULL; sg_policy->policy = policy; raw_spin_lock_init(&sg_policy->update_lock); return sg_policy; } static void sugov_policy_free(struct sugov_policy *sg_policy) { kfree(sg_policy); } static int sugov_kthread_create(struct sugov_policy *sg_policy) { struct task_struct *thread; struct sched_attr attr = { .size = sizeof(struct sched_attr), .sched_policy = SCHED_DEADLINE, .sched_flags = SCHED_FLAG_SUGOV, .sched_nice = 0, .sched_priority = 0, /* * Fake (unused) bandwidth; workaround to "fix" * priority inheritance. */ .sched_runtime = 1000000, .sched_deadline = 10000000, .sched_period = 10000000, }; struct cpufreq_policy *policy = sg_policy->policy; int ret; /* kthread only required for slow path */ if (policy->fast_switch_enabled) return 0; kthread_init_work(&sg_policy->work, sugov_work); kthread_init_worker(&sg_policy->worker); thread = kthread_create(kthread_worker_fn, &sg_policy->worker, "sugov:%d", cpumask_first(policy->related_cpus)); if (IS_ERR(thread)) { pr_err("failed to create sugov thread: %ld\n", PTR_ERR(thread)); return PTR_ERR(thread); } ret = sched_setattr_nocheck(thread, &attr); if (ret) { kthread_stop(thread); pr_warn("%s: failed to set SCHED_DEADLINE\n", __func__); return ret; } sg_policy->thread = thread; if (!policy->dvfs_possible_from_any_cpu) kthread_bind_mask(thread, policy->related_cpus); init_irq_work(&sg_policy->irq_work, sugov_irq_work); mutex_init(&sg_policy->work_lock); wake_up_process(thread); return 0; } static void sugov_kthread_stop(struct sugov_policy *sg_policy) { /* kthread only required for slow path */ if (sg_policy->policy->fast_switch_enabled) return; kthread_flush_worker(&sg_policy->worker); kthread_stop(sg_policy->thread); mutex_destroy(&sg_policy->work_lock); } static struct sugov_tunables *sugov_tunables_alloc(struct sugov_policy *sg_policy) { struct sugov_tunables *tunables; tunables = kzalloc(sizeof(*tunables), GFP_KERNEL); if (tunables) { gov_attr_set_init(&tunables->attr_set, &sg_policy->tunables_hook); if (!have_governor_per_policy()) global_tunables = tunables; } return tunables; } static void sugov_clear_global_tunables(void) { if (!have_governor_per_policy()) global_tunables = NULL; } static int sugov_init(struct cpufreq_policy *policy) { struct sugov_policy *sg_policy; struct sugov_tunables *tunables; int ret = 0; /* State should be equivalent to EXIT */ if (policy->governor_data) return -EBUSY; cpufreq_enable_fast_switch(policy); sg_policy = sugov_policy_alloc(policy); if (!sg_policy) { ret = -ENOMEM; goto disable_fast_switch; } ret = sugov_kthread_create(sg_policy); if (ret) goto free_sg_policy; mutex_lock(&global_tunables_lock); if (global_tunables) { if (WARN_ON(have_governor_per_policy())) { ret = -EINVAL; goto stop_kthread; } policy->governor_data = sg_policy; sg_policy->tunables = global_tunables; gov_attr_set_get(&global_tunables->attr_set, &sg_policy->tunables_hook); goto out; } tunables = sugov_tunables_alloc(sg_policy); if (!tunables) { ret = -ENOMEM; goto stop_kthread; } tunables->up_rate_limit_us = 500; tunables->down_rate_limit_us = 1000; tunables->efficient_freq = default_efficient_freq; tunables->nefficient_freq = ARRAY_SIZE(default_efficient_freq); tunables->up_delay = default_up_delay; tunables->nup_delay = ARRAY_SIZE(default_up_delay); policy->governor_data = sg_policy; sg_policy->tunables = tunables; ret = kobject_init_and_add(&tunables->attr_set.kobj, &sugov_tunables_ktype, get_governor_parent_kobj(policy), "%s", schedhorizon_gov.name); if (ret) goto fail; out: mutex_unlock(&global_tunables_lock); return 0; fail: kobject_put(&tunables->attr_set.kobj); policy->governor_data = NULL; sugov_clear_global_tunables(); stop_kthread: sugov_kthread_stop(sg_policy); mutex_unlock(&global_tunables_lock); free_sg_policy: sugov_policy_free(sg_policy); disable_fast_switch: cpufreq_disable_fast_switch(policy); pr_err("initialization failed (error %d)\n", ret); return ret; } static void sugov_exit(struct cpufreq_policy *policy) { struct sugov_policy *sg_policy = policy->governor_data; struct sugov_tunables *tunables = sg_policy->tunables; unsigned int count; mutex_lock(&global_tunables_lock); count = gov_attr_set_put(&tunables->attr_set, &sg_policy->tunables_hook); policy->governor_data = NULL; if (!count) sugov_clear_global_tunables(); mutex_unlock(&global_tunables_lock); sugov_kthread_stop(sg_policy); sugov_policy_free(sg_policy); cpufreq_disable_fast_switch(policy); } static int sugov_start(struct cpufreq_policy *policy) { struct sugov_policy *sg_policy = policy->governor_data; unsigned int cpu; sg_policy->up_rate_delay_ns = sg_policy->tunables->up_rate_limit_us * NSEC_PER_USEC; sg_policy->down_rate_delay_ns = sg_policy->tunables->down_rate_limit_us * NSEC_PER_USEC; update_min_rate_limit_ns(sg_policy); sg_policy->last_freq_update_time = 0; sg_policy->next_freq = 0; sg_policy->work_in_progress = false; sg_policy->limits_changed = false; sg_policy->cached_raw_freq = 0; sg_policy->need_freq_update = cpufreq_driver_test_flags(CPUFREQ_NEED_UPDATE_LIMITS); for_each_cpu(cpu, policy->cpus) { struct sugov_cpu *sg_cpu = &per_cpu(sugov_cpu, cpu); memset(sg_cpu, 0, sizeof(*sg_cpu)); sg_cpu->cpu = cpu; sg_cpu->sg_policy = sg_policy; } for_each_cpu(cpu, policy->cpus) { struct sugov_cpu *sg_cpu = &per_cpu(sugov_cpu, cpu); cpufreq_add_update_util_hook(cpu, &sg_cpu->update_util, policy_is_shared(policy) ? sugov_update_shared : sugov_update_single); } return 0; } static void sugov_stop(struct cpufreq_policy *policy) { struct sugov_policy *sg_policy = policy->governor_data; unsigned int cpu; for_each_cpu(cpu, policy->cpus) cpufreq_remove_update_util_hook(cpu); synchronize_rcu(); if (!policy->fast_switch_enabled) { irq_work_sync(&sg_policy->irq_work); kthread_cancel_work_sync(&sg_policy->work); } } static void sugov_limits(struct cpufreq_policy *policy) { struct sugov_policy *sg_policy = policy->governor_data; if (!policy->fast_switch_enabled) { mutex_lock(&sg_policy->work_lock); cpufreq_policy_apply_limits(policy); mutex_unlock(&sg_policy->work_lock); } sg_policy->limits_changed = true; } struct cpufreq_governor schedhorizon_gov = { .name = "schedhorizon", .owner = THIS_MODULE, .flags = CPUFREQ_GOV_DYNAMIC_SWITCHING, .init = sugov_init, .exit = sugov_exit, .start = sugov_start, .stop = sugov_stop, .limits = sugov_limits, }; #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDHORIZON struct cpufreq_governor *cpufreq_default_governor(void) { return &schedhorizon_gov; } #endif cpufreq_governor_init(schedhorizon_gov);