diff options
Diffstat (limited to 'kernel/sched/hmp.c')
| -rw-r--r-- | kernel/sched/hmp.c | 4416 |
1 files changed, 4416 insertions, 0 deletions
diff --git a/kernel/sched/hmp.c b/kernel/sched/hmp.c new file mode 100644 index 000000000000..598656b42203 --- /dev/null +++ b/kernel/sched/hmp.c @@ -0,0 +1,4416 @@ +/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * Implementation credits: Srivatsa Vaddagiri, Steve Muckle + * Syed Rameez Mustafa, Olav haugan, Joonwoo Park, Pavan Kumar Kondeti + * and Vikram Mulukutla + */ + +#include <linux/cpufreq.h> +#include <linux/list_sort.h> +#include <linux/syscore_ops.h> + +#include "sched.h" + +#include <trace/events/sched.h> + +#define CSTATE_LATENCY_GRANULARITY_SHIFT (6) + +const char *task_event_names[] = {"PUT_PREV_TASK", "PICK_NEXT_TASK", + "TASK_WAKE", "TASK_MIGRATE", "TASK_UPDATE", + "IRQ_UPDATE"}; + +const char *migrate_type_names[] = {"GROUP_TO_RQ", "RQ_TO_GROUP"}; + +static ktime_t ktime_last; +static bool sched_ktime_suspended; + +static bool use_cycle_counter; +static struct cpu_cycle_counter_cb cpu_cycle_counter_cb; + +u64 sched_ktime_clock(void) +{ + if (unlikely(sched_ktime_suspended)) + return ktime_to_ns(ktime_last); + return ktime_get_ns(); +} + +static void sched_resume(void) +{ + sched_ktime_suspended = false; +} + +static int sched_suspend(void) +{ + ktime_last = ktime_get(); + sched_ktime_suspended = true; + return 0; +} + +static struct syscore_ops sched_syscore_ops = { + .resume = sched_resume, + .suspend = sched_suspend +}; + +static int __init sched_init_ops(void) +{ + register_syscore_ops(&sched_syscore_ops); + return 0; +} +late_initcall(sched_init_ops); + +inline void clear_ed_task(struct task_struct *p, struct rq *rq) +{ + if (p == rq->ed_task) + rq->ed_task = NULL; +} + +inline void set_task_last_switch_out(struct task_struct *p, u64 wallclock) +{ + p->last_switch_out_ts = wallclock; +} + +/* + * Note C-state for (idle) cpus. + * + * @cstate = cstate index, 0 -> active state + * @wakeup_energy = energy spent in waking up cpu + * @wakeup_latency = latency to wakeup from cstate + * + */ +void +sched_set_cpu_cstate(int cpu, int cstate, int wakeup_energy, int wakeup_latency) +{ + struct rq *rq = cpu_rq(cpu); + + rq->cstate = cstate; /* C1, C2 etc */ + rq->wakeup_energy = wakeup_energy; + /* disregard small latency delta (64 us). */ + rq->wakeup_latency = ((wakeup_latency >> + CSTATE_LATENCY_GRANULARITY_SHIFT) << + CSTATE_LATENCY_GRANULARITY_SHIFT); +} + +/* + * Note D-state for (idle) cluster. + * + * @dstate = dstate index, 0 -> active state + * @wakeup_energy = energy spent in waking up cluster + * @wakeup_latency = latency to wakeup from cluster + * + */ +void sched_set_cluster_dstate(const cpumask_t *cluster_cpus, int dstate, + int wakeup_energy, int wakeup_latency) +{ + struct sched_cluster *cluster = + cpu_rq(cpumask_first(cluster_cpus))->cluster; + cluster->dstate = dstate; + cluster->dstate_wakeup_energy = wakeup_energy; + cluster->dstate_wakeup_latency = wakeup_latency; +} + +u32 __weak get_freq_max_load(int cpu, u32 freq) +{ + /* 100% by default */ + return 100; +} + +struct freq_max_load_entry { + /* The maximum load which has accounted governor's headroom. */ + u64 hdemand; +}; + +struct freq_max_load { + struct rcu_head rcu; + int length; + struct freq_max_load_entry freqs[0]; +}; + +static DEFINE_PER_CPU(struct freq_max_load *, freq_max_load); +static DEFINE_SPINLOCK(freq_max_load_lock); + +struct cpu_pwr_stats __weak *get_cpu_pwr_stats(void) +{ + return NULL; +} + +int sched_update_freq_max_load(const cpumask_t *cpumask) +{ + int i, cpu, ret; + unsigned int freq; + struct cpu_pstate_pwr *costs; + struct cpu_pwr_stats *per_cpu_info = get_cpu_pwr_stats(); + struct freq_max_load *max_load, *old_max_load; + struct freq_max_load_entry *entry; + u64 max_demand_capacity, max_demand; + unsigned long flags; + u32 hfreq; + int hpct; + + if (!per_cpu_info) + return 0; + + spin_lock_irqsave(&freq_max_load_lock, flags); + max_demand_capacity = div64_u64(max_task_load(), max_possible_capacity); + for_each_cpu(cpu, cpumask) { + if (!per_cpu_info[cpu].ptable) { + ret = -EINVAL; + goto fail; + } + + old_max_load = rcu_dereference(per_cpu(freq_max_load, cpu)); + + /* + * allocate len + 1 and leave the last power cost as 0 for + * power_cost() can stop iterating index when + * per_cpu_info[cpu].len > len of max_load due to race between + * cpu power stats update and get_cpu_pwr_stats(). + */ + max_load = kzalloc(sizeof(struct freq_max_load) + + sizeof(struct freq_max_load_entry) * + (per_cpu_info[cpu].len + 1), GFP_ATOMIC); + if (unlikely(!max_load)) { + ret = -ENOMEM; + goto fail; + } + + max_load->length = per_cpu_info[cpu].len; + + max_demand = max_demand_capacity * + cpu_max_possible_capacity(cpu); + + i = 0; + costs = per_cpu_info[cpu].ptable; + while (costs[i].freq) { + entry = &max_load->freqs[i]; + freq = costs[i].freq; + hpct = get_freq_max_load(cpu, freq); + if (hpct <= 0 || hpct > 100) + hpct = 100; + hfreq = div64_u64((u64)freq * hpct, 100); + entry->hdemand = + div64_u64(max_demand * hfreq, + cpu_max_possible_freq(cpu)); + i++; + } + + rcu_assign_pointer(per_cpu(freq_max_load, cpu), max_load); + if (old_max_load) + kfree_rcu(old_max_load, rcu); + } + + spin_unlock_irqrestore(&freq_max_load_lock, flags); + return 0; + +fail: + for_each_cpu(cpu, cpumask) { + max_load = rcu_dereference(per_cpu(freq_max_load, cpu)); + if (max_load) { + rcu_assign_pointer(per_cpu(freq_max_load, cpu), NULL); + kfree_rcu(max_load, rcu); + } + } + + spin_unlock_irqrestore(&freq_max_load_lock, flags); + return ret; +} + +unsigned int max_possible_efficiency = 1; +unsigned int min_possible_efficiency = UINT_MAX; + +unsigned long __weak arch_get_cpu_efficiency(int cpu) +{ + return SCHED_LOAD_SCALE; +} + +/* Keep track of max/min capacity possible across CPUs "currently" */ +static void __update_min_max_capacity(void) +{ + int i; + int max_cap = 0, min_cap = INT_MAX; + + for_each_online_cpu(i) { + max_cap = max(max_cap, cpu_capacity(i)); + min_cap = min(min_cap, cpu_capacity(i)); + } + + max_capacity = max_cap; + min_capacity = min_cap; +} + +static void update_min_max_capacity(void) +{ + unsigned long flags; + int i; + + local_irq_save(flags); + for_each_possible_cpu(i) + raw_spin_lock(&cpu_rq(i)->lock); + + __update_min_max_capacity(); + + for_each_possible_cpu(i) + raw_spin_unlock(&cpu_rq(i)->lock); + local_irq_restore(flags); +} + +/* + * Return 'capacity' of a cpu in reference to "least" efficient cpu, such that + * least efficient cpu gets capacity of 1024 + */ +static unsigned long +capacity_scale_cpu_efficiency(struct sched_cluster *cluster) +{ + return (1024 * cluster->efficiency) / min_possible_efficiency; +} + +/* + * Return 'capacity' of a cpu in reference to cpu with lowest max_freq + * (min_max_freq), such that one with lowest max_freq gets capacity of 1024. + */ +static unsigned long capacity_scale_cpu_freq(struct sched_cluster *cluster) +{ + return (1024 * cluster_max_freq(cluster)) / min_max_freq; +} + +/* + * Return load_scale_factor of a cpu in reference to "most" efficient cpu, so + * that "most" efficient cpu gets a load_scale_factor of 1 + */ +static inline unsigned long +load_scale_cpu_efficiency(struct sched_cluster *cluster) +{ + return DIV_ROUND_UP(1024 * max_possible_efficiency, + cluster->efficiency); +} + +/* + * Return load_scale_factor of a cpu in reference to cpu with best max_freq + * (max_possible_freq), so that one with best max_freq gets a load_scale_factor + * of 1. + */ +static inline unsigned long load_scale_cpu_freq(struct sched_cluster *cluster) +{ + return DIV_ROUND_UP(1024 * max_possible_freq, + cluster_max_freq(cluster)); +} + +static int compute_capacity(struct sched_cluster *cluster) +{ + int capacity = 1024; + + capacity *= capacity_scale_cpu_efficiency(cluster); + capacity >>= 10; + + capacity *= capacity_scale_cpu_freq(cluster); + capacity >>= 10; + + return capacity; +} + +static int compute_max_possible_capacity(struct sched_cluster *cluster) +{ + int capacity = 1024; + + capacity *= capacity_scale_cpu_efficiency(cluster); + capacity >>= 10; + + capacity *= (1024 * cluster->max_possible_freq) / min_max_freq; + capacity >>= 10; + + return capacity; +} + +static int compute_load_scale_factor(struct sched_cluster *cluster) +{ + int load_scale = 1024; + + /* + * load_scale_factor accounts for the fact that task load + * is in reference to "best" performing cpu. Task's load will need to be + * scaled (up) by a factor to determine suitability to be placed on a + * (little) cpu. + */ + load_scale *= load_scale_cpu_efficiency(cluster); + load_scale >>= 10; + + load_scale *= load_scale_cpu_freq(cluster); + load_scale >>= 10; + + return load_scale; +} + +struct list_head cluster_head; +static DEFINE_MUTEX(cluster_lock); +static cpumask_t all_cluster_cpus = CPU_MASK_NONE; +DECLARE_BITMAP(all_cluster_ids, NR_CPUS); +struct sched_cluster *sched_cluster[NR_CPUS]; +int num_clusters; + +unsigned int max_power_cost = 1; + +struct sched_cluster init_cluster = { + .list = LIST_HEAD_INIT(init_cluster.list), + .id = 0, + .max_power_cost = 1, + .min_power_cost = 1, + .capacity = 1024, + .max_possible_capacity = 1024, + .efficiency = 1, + .load_scale_factor = 1024, + .cur_freq = 1, + .max_freq = 1, + .max_mitigated_freq = UINT_MAX, + .min_freq = 1, + .max_possible_freq = 1, + .dstate = 0, + .dstate_wakeup_energy = 0, + .dstate_wakeup_latency = 0, + .exec_scale_factor = 1024, + .notifier_sent = 0, + .wake_up_idle = 0, +}; + +static void update_all_clusters_stats(void) +{ + struct sched_cluster *cluster; + u64 highest_mpc = 0, lowest_mpc = U64_MAX; + + pre_big_task_count_change(cpu_possible_mask); + + for_each_sched_cluster(cluster) { + u64 mpc; + + cluster->capacity = compute_capacity(cluster); + mpc = cluster->max_possible_capacity = + compute_max_possible_capacity(cluster); + cluster->load_scale_factor = compute_load_scale_factor(cluster); + + cluster->exec_scale_factor = + DIV_ROUND_UP(cluster->efficiency * 1024, + max_possible_efficiency); + + if (mpc > highest_mpc) + highest_mpc = mpc; + + if (mpc < lowest_mpc) + lowest_mpc = mpc; + } + + max_possible_capacity = highest_mpc; + min_max_possible_capacity = lowest_mpc; + + __update_min_max_capacity(); + sched_update_freq_max_load(cpu_possible_mask); + post_big_task_count_change(cpu_possible_mask); +} + +static void assign_cluster_ids(struct list_head *head) +{ + struct sched_cluster *cluster; + int pos = 0; + + list_for_each_entry(cluster, head, list) { + cluster->id = pos; + sched_cluster[pos++] = cluster; + } +} + +static void +move_list(struct list_head *dst, struct list_head *src, bool sync_rcu) +{ + struct list_head *first, *last; + + first = src->next; + last = src->prev; + + if (sync_rcu) { + INIT_LIST_HEAD_RCU(src); + synchronize_rcu(); + } + + first->prev = dst; + dst->prev = last; + last->next = dst; + + /* Ensure list sanity before making the head visible to all CPUs. */ + smp_mb(); + dst->next = first; +} + +static int +compare_clusters(void *priv, struct list_head *a, struct list_head *b) +{ + struct sched_cluster *cluster1, *cluster2; + int ret; + + cluster1 = container_of(a, struct sched_cluster, list); + cluster2 = container_of(b, struct sched_cluster, list); + + /* + * Don't assume higher capacity means higher power. If the + * power cost is same, sort the higher capacity cluster before + * the lower capacity cluster to start placing the tasks + * on the higher capacity cluster. + */ + ret = cluster1->max_power_cost > cluster2->max_power_cost || + (cluster1->max_power_cost == cluster2->max_power_cost && + cluster1->max_possible_capacity < + cluster2->max_possible_capacity); + + return ret; +} + +static void sort_clusters(void) +{ + struct sched_cluster *cluster; + struct list_head new_head; + unsigned int tmp_max = 1; + + INIT_LIST_HEAD(&new_head); + + for_each_sched_cluster(cluster) { + cluster->max_power_cost = power_cost(cluster_first_cpu(cluster), + max_task_load()); + cluster->min_power_cost = power_cost(cluster_first_cpu(cluster), + 0); + + if (cluster->max_power_cost > tmp_max) + tmp_max = cluster->max_power_cost; + } + max_power_cost = tmp_max; + + move_list(&new_head, &cluster_head, true); + + list_sort(NULL, &new_head, compare_clusters); + assign_cluster_ids(&new_head); + + /* + * Ensure cluster ids are visible to all CPUs before making + * cluster_head visible. + */ + move_list(&cluster_head, &new_head, false); +} + +static void +insert_cluster(struct sched_cluster *cluster, struct list_head *head) +{ + struct sched_cluster *tmp; + struct list_head *iter = head; + + list_for_each_entry(tmp, head, list) { + if (cluster->max_power_cost < tmp->max_power_cost) + break; + iter = &tmp->list; + } + + list_add(&cluster->list, iter); +} + +static struct sched_cluster *alloc_new_cluster(const struct cpumask *cpus) +{ + struct sched_cluster *cluster = NULL; + + cluster = kzalloc(sizeof(struct sched_cluster), GFP_ATOMIC); + if (!cluster) { + __WARN_printf("Cluster allocation failed. \ + Possible bad scheduling\n"); + return NULL; + } + + INIT_LIST_HEAD(&cluster->list); + cluster->max_power_cost = 1; + cluster->min_power_cost = 1; + cluster->capacity = 1024; + cluster->max_possible_capacity = 1024; + cluster->efficiency = 1; + cluster->load_scale_factor = 1024; + cluster->cur_freq = 1; + cluster->max_freq = 1; + cluster->max_mitigated_freq = UINT_MAX; + cluster->min_freq = 1; + cluster->max_possible_freq = 1; + cluster->dstate = 0; + cluster->dstate_wakeup_energy = 0; + cluster->dstate_wakeup_latency = 0; + cluster->freq_init_done = false; + + raw_spin_lock_init(&cluster->load_lock); + cluster->cpus = *cpus; + cluster->efficiency = arch_get_cpu_efficiency(cpumask_first(cpus)); + + if (cluster->efficiency > max_possible_efficiency) + max_possible_efficiency = cluster->efficiency; + if (cluster->efficiency < min_possible_efficiency) + min_possible_efficiency = cluster->efficiency; + + cluster->notifier_sent = 0; + return cluster; +} + +static void add_cluster(const struct cpumask *cpus, struct list_head *head) +{ + struct sched_cluster *cluster = alloc_new_cluster(cpus); + int i; + + if (!cluster) + return; + + for_each_cpu(i, cpus) + cpu_rq(i)->cluster = cluster; + + insert_cluster(cluster, head); + set_bit(num_clusters, all_cluster_ids); + num_clusters++; +} + +void update_cluster_topology(void) +{ + struct cpumask cpus = *cpu_possible_mask; + const struct cpumask *cluster_cpus; + struct list_head new_head; + int i; + + INIT_LIST_HEAD(&new_head); + + for_each_cpu(i, &cpus) { + cluster_cpus = cpu_coregroup_mask(i); + cpumask_or(&all_cluster_cpus, &all_cluster_cpus, cluster_cpus); + cpumask_andnot(&cpus, &cpus, cluster_cpus); + add_cluster(cluster_cpus, &new_head); + } + + assign_cluster_ids(&new_head); + + /* + * Ensure cluster ids are visible to all CPUs before making + * cluster_head visible. + */ + move_list(&cluster_head, &new_head, false); + update_all_clusters_stats(); +} + +void init_clusters(void) +{ + bitmap_clear(all_cluster_ids, 0, NR_CPUS); + init_cluster.cpus = *cpu_possible_mask; + raw_spin_lock_init(&init_cluster.load_lock); + INIT_LIST_HEAD(&cluster_head); +} + +int register_cpu_cycle_counter_cb(struct cpu_cycle_counter_cb *cb) +{ + mutex_lock(&cluster_lock); + if (!cb->get_cpu_cycle_counter) { + mutex_unlock(&cluster_lock); + return -EINVAL; + } + + cpu_cycle_counter_cb = *cb; + use_cycle_counter = true; + mutex_unlock(&cluster_lock); + + return 0; +} + +/* Clear any HMP scheduler related requests pending from or on cpu */ +void clear_hmp_request(int cpu) +{ + struct rq *rq = cpu_rq(cpu); + unsigned long flags; + + clear_boost_kick(cpu); + clear_reserved(cpu); + if (rq->push_task) { + struct task_struct *push_task = NULL; + + raw_spin_lock_irqsave(&rq->lock, flags); + if (rq->push_task) { + clear_reserved(rq->push_cpu); + push_task = rq->push_task; + rq->push_task = NULL; + } + rq->active_balance = 0; + raw_spin_unlock_irqrestore(&rq->lock, flags); + if (push_task) + put_task_struct(push_task); + } +} + +int sched_set_static_cpu_pwr_cost(int cpu, unsigned int cost) +{ + struct rq *rq = cpu_rq(cpu); + + rq->static_cpu_pwr_cost = cost; + return 0; +} + +unsigned int sched_get_static_cpu_pwr_cost(int cpu) +{ + return cpu_rq(cpu)->static_cpu_pwr_cost; +} + +int sched_set_static_cluster_pwr_cost(int cpu, unsigned int cost) +{ + struct sched_cluster *cluster = cpu_rq(cpu)->cluster; + + cluster->static_cluster_pwr_cost = cost; + return 0; +} + +unsigned int sched_get_static_cluster_pwr_cost(int cpu) +{ + return cpu_rq(cpu)->cluster->static_cluster_pwr_cost; +} + +int sched_set_cluster_wake_idle(int cpu, unsigned int wake_idle) +{ + struct sched_cluster *cluster = cpu_rq(cpu)->cluster; + + cluster->wake_up_idle = !!wake_idle; + return 0; +} + +unsigned int sched_get_cluster_wake_idle(int cpu) +{ + return cpu_rq(cpu)->cluster->wake_up_idle; +} + +/* + * sched_window_stats_policy and sched_ravg_hist_size have a 'sysctl' copy + * associated with them. This is required for atomic update of those variables + * when being modifed via sysctl interface. + * + * IMPORTANT: Initialize both copies to same value!! + */ + +/* + * Tasks that are runnable continuously for a period greather than + * EARLY_DETECTION_DURATION can be flagged early as potential + * high load tasks. + */ +#define EARLY_DETECTION_DURATION 9500000 + +static __read_mostly unsigned int sched_ravg_hist_size = 5; +__read_mostly unsigned int sysctl_sched_ravg_hist_size = 5; + +static __read_mostly unsigned int sched_window_stats_policy = + WINDOW_STATS_MAX_RECENT_AVG; +__read_mostly unsigned int sysctl_sched_window_stats_policy = + WINDOW_STATS_MAX_RECENT_AVG; + +#define SCHED_ACCOUNT_WAIT_TIME 1 + +__read_mostly unsigned int sysctl_sched_cpu_high_irqload = (10 * NSEC_PER_MSEC); + +/* + * Enable colocation and frequency aggregation for all threads in a process. + * The children inherits the group id from the parent. + */ +unsigned int __read_mostly sysctl_sched_enable_thread_grouping; + + +#define SCHED_NEW_TASK_WINDOWS 5 + +#define SCHED_FREQ_ACCOUNT_WAIT_TIME 0 + +/* + * This governs what load needs to be used when reporting CPU busy time + * to the cpufreq governor. + */ +__read_mostly unsigned int sysctl_sched_freq_reporting_policy; + +/* + * For increase, send notification if + * freq_required - cur_freq > sysctl_sched_freq_inc_notify + */ +__read_mostly int sysctl_sched_freq_inc_notify = 10 * 1024 * 1024; /* + 10GHz */ + +/* + * For decrease, send notification if + * cur_freq - freq_required > sysctl_sched_freq_dec_notify + */ +__read_mostly int sysctl_sched_freq_dec_notify = 10 * 1024 * 1024; /* - 10GHz */ + +static __read_mostly unsigned int sched_io_is_busy; + +__read_mostly unsigned int sysctl_sched_pred_alert_freq = 10 * 1024 * 1024; + +/* + * Maximum possible frequency across all cpus. Task demand and cpu + * capacity (cpu_power) metrics are scaled in reference to it. + */ +unsigned int max_possible_freq = 1; + +/* + * Minimum possible max_freq across all cpus. This will be same as + * max_possible_freq on homogeneous systems and could be different from + * max_possible_freq on heterogenous systems. min_max_freq is used to derive + * capacity (cpu_power) of cpus. + */ +unsigned int min_max_freq = 1; + +unsigned int max_capacity = 1024; /* max(rq->capacity) */ +unsigned int min_capacity = 1024; /* min(rq->capacity) */ +unsigned int max_possible_capacity = 1024; /* max(rq->max_possible_capacity) */ +unsigned int +min_max_possible_capacity = 1024; /* min(rq->max_possible_capacity) */ + +/* Min window size (in ns) = 10ms */ +#define MIN_SCHED_RAVG_WINDOW 10000000 + +/* Max window size (in ns) = 1s */ +#define MAX_SCHED_RAVG_WINDOW 1000000000 + +/* Window size (in ns) */ +__read_mostly unsigned int sched_ravg_window = MIN_SCHED_RAVG_WINDOW; + +/* Maximum allowed threshold before freq aggregation must be enabled */ +#define MAX_FREQ_AGGR_THRESH 1000 + +/* Temporarily disable window-stats activity on all cpus */ +unsigned int __read_mostly sched_disable_window_stats; + +struct related_thread_group *related_thread_groups[MAX_NUM_CGROUP_COLOC_ID]; +static LIST_HEAD(active_related_thread_groups); +static DEFINE_RWLOCK(related_thread_group_lock); + +#define for_each_related_thread_group(grp) \ + list_for_each_entry(grp, &active_related_thread_groups, list) + +/* + * Task load is categorized into buckets for the purpose of top task tracking. + * The entire range of load from 0 to sched_ravg_window needs to be covered + * in NUM_LOAD_INDICES number of buckets. Therefore the size of each bucket + * is given by sched_ravg_window / NUM_LOAD_INDICES. Since the default value + * of sched_ravg_window is MIN_SCHED_RAVG_WINDOW, use that to compute + * sched_load_granule. + */ +__read_mostly unsigned int sched_load_granule = + MIN_SCHED_RAVG_WINDOW / NUM_LOAD_INDICES; + +/* Size of bitmaps maintained to track top tasks */ +static const unsigned int top_tasks_bitmap_size = + BITS_TO_LONGS(NUM_LOAD_INDICES + 1) * sizeof(unsigned long); + +/* + * Demand aggregation for frequency purpose: + * + * 'sched_freq_aggregate' controls aggregation of cpu demand of related threads + * for frequency determination purpose. This aggregation is done per-cluster. + * + * CPU demand of tasks from various related groups is aggregated per-cluster and + * added to the "max_busy_cpu" in that cluster, where max_busy_cpu is determined + * by just rq->prev_runnable_sum. + * + * Some examples follow, which assume: + * Cluster0 = CPU0-3, Cluster1 = CPU4-7 + * One related thread group A that has tasks A0, A1, A2 + * + * A->cpu_time[X].curr/prev_sum = counters in which cpu execution stats of + * tasks belonging to group A are accumulated when they run on cpu X. + * + * CX->curr/prev_sum = counters in which cpu execution stats of all tasks + * not belonging to group A are accumulated when they run on cpu X + * + * Lets say the stats for window M was as below: + * + * C0->prev_sum = 1ms, A->cpu_time[0].prev_sum = 5ms + * Task A0 ran 5ms on CPU0 + * Task B0 ran 1ms on CPU0 + * + * C1->prev_sum = 5ms, A->cpu_time[1].prev_sum = 6ms + * Task A1 ran 4ms on CPU1 + * Task A2 ran 2ms on CPU1 + * Task B1 ran 5ms on CPU1 + * + * C2->prev_sum = 0ms, A->cpu_time[2].prev_sum = 0 + * CPU2 idle + * + * C3->prev_sum = 0ms, A->cpu_time[3].prev_sum = 0 + * CPU3 idle + * + * In this case, CPU1 was most busy going by just its prev_sum counter. Demand + * from all group A tasks are added to CPU1. IOW, at end of window M, cpu busy + * time reported to governor will be: + * + * + * C0 busy time = 1ms + * C1 busy time = 5 + 5 + 6 = 16ms + * + */ +static __read_mostly unsigned int sched_freq_aggregate = 1; +__read_mostly unsigned int sysctl_sched_freq_aggregate = 1; + +unsigned int __read_mostly sysctl_sched_freq_aggregate_threshold_pct; +static unsigned int __read_mostly sched_freq_aggregate_threshold; + +/* Initial task load. Newly created tasks are assigned this load. */ +unsigned int __read_mostly sched_init_task_load_windows; +unsigned int __read_mostly sysctl_sched_init_task_load_pct = 15; + +unsigned int max_task_load(void) +{ + return sched_ravg_window; +} + +/* A cpu can no longer accommodate more tasks if: + * + * rq->nr_running > sysctl_sched_spill_nr_run || + * rq->hmp_stats.cumulative_runnable_avg > sched_spill_load + */ +unsigned int __read_mostly sysctl_sched_spill_nr_run = 10; + +/* + * Place sync wakee tasks those have less than configured demand to the waker's + * cluster. + */ +unsigned int __read_mostly sched_small_wakee_task_load; +unsigned int __read_mostly sysctl_sched_small_wakee_task_load_pct = 10; + +unsigned int __read_mostly sched_big_waker_task_load; +unsigned int __read_mostly sysctl_sched_big_waker_task_load_pct = 25; + +/* + * CPUs with load greater than the sched_spill_load_threshold are not + * eligible for task placement. When all CPUs in a cluster achieve a + * load higher than this level, tasks becomes eligible for inter + * cluster migration. + */ +unsigned int __read_mostly sched_spill_load; +unsigned int __read_mostly sysctl_sched_spill_load_pct = 100; + +/* + * Prefer the waker CPU for sync wakee task, if the CPU has only 1 runnable + * task. This eliminates the LPM exit latency associated with the idle + * CPUs in the waker cluster. + */ +unsigned int __read_mostly sysctl_sched_prefer_sync_wakee_to_waker; + +/* + * Tasks whose bandwidth consumption on a cpu is more than + * sched_upmigrate are considered "big" tasks. Big tasks will be + * considered for "up" migration, i.e migrating to a cpu with better + * capacity. + */ +unsigned int __read_mostly sched_upmigrate; +unsigned int __read_mostly sysctl_sched_upmigrate_pct = 80; + +/* + * Big tasks, once migrated, will need to drop their bandwidth + * consumption to less than sched_downmigrate before they are "down" + * migrated. + */ +unsigned int __read_mostly sched_downmigrate; +unsigned int __read_mostly sysctl_sched_downmigrate_pct = 60; + +/* + * Task groups whose aggregate demand on a cpu is more than + * sched_group_upmigrate need to be up-migrated if possible. + */ +unsigned int __read_mostly sched_group_upmigrate; +unsigned int __read_mostly sysctl_sched_group_upmigrate_pct = 100; + +/* + * Task groups, once up-migrated, will need to drop their aggregate + * demand to less than sched_group_downmigrate before they are "down" + * migrated. + */ +unsigned int __read_mostly sched_group_downmigrate; +unsigned int __read_mostly sysctl_sched_group_downmigrate_pct = 95; + +/* + * The load scale factor of a CPU gets boosted when its max frequency + * is restricted due to which the tasks are migrating to higher capacity + * CPUs early. The sched_upmigrate threshold is auto-upgraded by + * rq->max_possible_freq/rq->max_freq of a lower capacity CPU. + */ +unsigned int up_down_migrate_scale_factor = 1024; + +/* + * Scheduler selects and places task to its previous CPU if sleep time is + * less than sysctl_sched_select_prev_cpu_us. + */ +unsigned int __read_mostly +sched_short_sleep_task_threshold = 2000 * NSEC_PER_USEC; + +unsigned int __read_mostly sysctl_sched_select_prev_cpu_us = 2000; + +unsigned int __read_mostly +sched_long_cpu_selection_threshold = 100 * NSEC_PER_MSEC; + +unsigned int __read_mostly sysctl_sched_restrict_cluster_spill; + +/* + * Scheduler tries to avoid waking up idle CPUs for tasks running + * in short bursts. If the task average burst is less than + * sysctl_sched_short_burst nanoseconds and it sleeps on an average + * for more than sysctl_sched_short_sleep nanoseconds, then the + * task is eligible for packing. + */ +unsigned int __read_mostly sysctl_sched_short_burst; +unsigned int __read_mostly sysctl_sched_short_sleep = 1 * NSEC_PER_MSEC; + +static void _update_up_down_migrate(unsigned int *up_migrate, + unsigned int *down_migrate, bool is_group) +{ + unsigned int delta; + + if (up_down_migrate_scale_factor == 1024) + return; + + delta = *up_migrate - *down_migrate; + + *up_migrate /= NSEC_PER_USEC; + *up_migrate *= up_down_migrate_scale_factor; + *up_migrate >>= 10; + *up_migrate *= NSEC_PER_USEC; + + if (!is_group) + *up_migrate = min(*up_migrate, sched_ravg_window); + + *down_migrate /= NSEC_PER_USEC; + *down_migrate *= up_down_migrate_scale_factor; + *down_migrate >>= 10; + *down_migrate *= NSEC_PER_USEC; + + *down_migrate = min(*down_migrate, *up_migrate - delta); +} + +static void update_up_down_migrate(void) +{ + unsigned int up_migrate = pct_to_real(sysctl_sched_upmigrate_pct); + unsigned int down_migrate = pct_to_real(sysctl_sched_downmigrate_pct); + + _update_up_down_migrate(&up_migrate, &down_migrate, false); + sched_upmigrate = up_migrate; + sched_downmigrate = down_migrate; + + up_migrate = pct_to_real(sysctl_sched_group_upmigrate_pct); + down_migrate = pct_to_real(sysctl_sched_group_downmigrate_pct); + + _update_up_down_migrate(&up_migrate, &down_migrate, true); + sched_group_upmigrate = up_migrate; + sched_group_downmigrate = down_migrate; +} + +void set_hmp_defaults(void) +{ + sched_spill_load = + pct_to_real(sysctl_sched_spill_load_pct); + + update_up_down_migrate(); + + sched_init_task_load_windows = + div64_u64((u64)sysctl_sched_init_task_load_pct * + (u64)sched_ravg_window, 100); + + sched_short_sleep_task_threshold = sysctl_sched_select_prev_cpu_us * + NSEC_PER_USEC; + + sched_small_wakee_task_load = + div64_u64((u64)sysctl_sched_small_wakee_task_load_pct * + (u64)sched_ravg_window, 100); + + sched_big_waker_task_load = + div64_u64((u64)sysctl_sched_big_waker_task_load_pct * + (u64)sched_ravg_window, 100); + + sched_freq_aggregate_threshold = + pct_to_real(sysctl_sched_freq_aggregate_threshold_pct); +} + +u32 sched_get_init_task_load(struct task_struct *p) +{ + return p->init_load_pct; +} + +int sched_set_init_task_load(struct task_struct *p, int init_load_pct) +{ + if (init_load_pct < 0 || init_load_pct > 100) + return -EINVAL; + + p->init_load_pct = init_load_pct; + + return 0; +} + +#ifdef CONFIG_CGROUP_SCHED + +int upmigrate_discouraged(struct task_struct *p) +{ + return task_group(p)->upmigrate_discouraged; +} + +#else + +static inline int upmigrate_discouraged(struct task_struct *p) +{ + return 0; +} + +#endif + +/* Is a task "big" on its current cpu */ +static inline int __is_big_task(struct task_struct *p, u64 scaled_load) +{ + int nice = task_nice(p); + + if (nice > SCHED_UPMIGRATE_MIN_NICE || upmigrate_discouraged(p)) + return 0; + + return scaled_load > sched_upmigrate; +} + +int is_big_task(struct task_struct *p) +{ + return __is_big_task(p, scale_load_to_cpu(task_load(p), task_cpu(p))); +} + +u64 cpu_load(int cpu) +{ + struct rq *rq = cpu_rq(cpu); + + return scale_load_to_cpu(rq->hmp_stats.cumulative_runnable_avg, cpu); +} + +u64 cpu_load_sync(int cpu, int sync) +{ + return scale_load_to_cpu(cpu_cravg_sync(cpu, sync), cpu); +} + +/* + * Task will fit on a cpu if it's bandwidth consumption on that cpu + * will be less than sched_upmigrate. A big task that was previously + * "up" migrated will be considered fitting on "little" cpu if its + * bandwidth consumption on "little" cpu will be less than + * sched_downmigrate. This will help avoid frequenty migrations for + * tasks with load close to the upmigrate threshold + */ +int task_load_will_fit(struct task_struct *p, u64 task_load, int cpu, + enum sched_boost_policy boost_policy) +{ + int upmigrate = sched_upmigrate; + + if (cpu_capacity(cpu) == max_capacity) + return 1; + + if (cpu_capacity(task_cpu(p)) > cpu_capacity(cpu)) + upmigrate = sched_downmigrate; + + if (boost_policy != SCHED_BOOST_ON_BIG) { + if (task_nice(p) > SCHED_UPMIGRATE_MIN_NICE || + upmigrate_discouraged(p)) + return 1; + + if (task_load < upmigrate) + return 1; + } else { + if (task_sched_boost(p) || task_load >= upmigrate) + return 0; + + return 1; + } + + return 0; +} + +int task_will_fit(struct task_struct *p, int cpu) +{ + u64 tload = scale_load_to_cpu(task_load(p), cpu); + + return task_load_will_fit(p, tload, cpu, sched_boost_policy()); +} + +static int +group_will_fit(struct sched_cluster *cluster, struct related_thread_group *grp, + u64 demand, bool group_boost) +{ + int cpu = cluster_first_cpu(cluster); + int prev_capacity = 0; + unsigned int threshold = sched_group_upmigrate; + u64 load; + + if (cluster->capacity == max_capacity) + return 1; + + if (group_boost) + return 0; + + if (!demand) + return 1; + + if (grp->preferred_cluster) + prev_capacity = grp->preferred_cluster->capacity; + + if (cluster->capacity < prev_capacity) + threshold = sched_group_downmigrate; + + load = scale_load_to_cpu(demand, cpu); + if (load < threshold) + return 1; + + return 0; +} + +/* + * Return the cost of running task p on CPU cpu. This function + * currently assumes that task p is the only task which will run on + * the CPU. + */ +unsigned int power_cost(int cpu, u64 demand) +{ + int first, mid, last; + struct cpu_pwr_stats *per_cpu_info = get_cpu_pwr_stats(); + struct cpu_pstate_pwr *costs; + struct freq_max_load *max_load; + int total_static_pwr_cost = 0; + struct rq *rq = cpu_rq(cpu); + unsigned int pc; + + if (!per_cpu_info || !per_cpu_info[cpu].ptable) + /* + * When power aware scheduling is not in use, or CPU + * power data is not available, just use the CPU + * capacity as a rough stand-in for real CPU power + * numbers, assuming bigger CPUs are more power + * hungry. + */ + return cpu_max_possible_capacity(cpu); + + rcu_read_lock(); + max_load = rcu_dereference(per_cpu(freq_max_load, cpu)); + if (!max_load) { + pc = cpu_max_possible_capacity(cpu); + goto unlock; + } + + costs = per_cpu_info[cpu].ptable; + + if (demand <= max_load->freqs[0].hdemand) { + pc = costs[0].power; + goto unlock; + } else if (demand > max_load->freqs[max_load->length - 1].hdemand) { + pc = costs[max_load->length - 1].power; + goto unlock; + } + + first = 0; + last = max_load->length - 1; + mid = (last - first) >> 1; + while (1) { + if (demand <= max_load->freqs[mid].hdemand) + last = mid; + else + first = mid; + + if (last - first == 1) + break; + mid = first + ((last - first) >> 1); + } + + pc = costs[last].power; + +unlock: + rcu_read_unlock(); + + if (idle_cpu(cpu) && rq->cstate) { + total_static_pwr_cost += rq->static_cpu_pwr_cost; + if (rq->cluster->dstate) + total_static_pwr_cost += + rq->cluster->static_cluster_pwr_cost; + } + + return pc + total_static_pwr_cost; + +} + +void inc_nr_big_task(struct hmp_sched_stats *stats, struct task_struct *p) +{ + if (sched_disable_window_stats) + return; + + if (is_big_task(p)) + stats->nr_big_tasks++; +} + +void dec_nr_big_task(struct hmp_sched_stats *stats, struct task_struct *p) +{ + if (sched_disable_window_stats) + return; + + if (is_big_task(p)) + stats->nr_big_tasks--; + + BUG_ON(stats->nr_big_tasks < 0); +} + +void inc_rq_hmp_stats(struct rq *rq, struct task_struct *p, int change_cra) +{ + inc_nr_big_task(&rq->hmp_stats, p); + if (change_cra) + inc_cumulative_runnable_avg(&rq->hmp_stats, p); +} + +void dec_rq_hmp_stats(struct rq *rq, struct task_struct *p, int change_cra) +{ + dec_nr_big_task(&rq->hmp_stats, p); + if (change_cra) + dec_cumulative_runnable_avg(&rq->hmp_stats, p); +} + +void reset_hmp_stats(struct hmp_sched_stats *stats, int reset_cra) +{ + stats->nr_big_tasks = 0; + if (reset_cra) { + stats->cumulative_runnable_avg = 0; + stats->pred_demands_sum = 0; + } +} + +int preferred_cluster(struct sched_cluster *cluster, struct task_struct *p) +{ + struct related_thread_group *grp; + int rc = 1; + + rcu_read_lock(); + + grp = task_related_thread_group(p); + if (grp) + rc = (grp->preferred_cluster == cluster); + + rcu_read_unlock(); + return rc; +} + +struct sched_cluster *rq_cluster(struct rq *rq) +{ + return rq->cluster; +} + +/* + * reset_cpu_hmp_stats - reset HMP stats for a cpu + * nr_big_tasks + * cumulative_runnable_avg (iff reset_cra is true) + */ +void reset_cpu_hmp_stats(int cpu, int reset_cra) +{ + reset_cfs_rq_hmp_stats(cpu, reset_cra); + reset_hmp_stats(&cpu_rq(cpu)->hmp_stats, reset_cra); +} + +void fixup_nr_big_tasks(struct hmp_sched_stats *stats, + struct task_struct *p, s64 delta) +{ + u64 new_task_load; + u64 old_task_load; + + if (sched_disable_window_stats) + return; + + old_task_load = scale_load_to_cpu(task_load(p), task_cpu(p)); + new_task_load = scale_load_to_cpu(delta + task_load(p), task_cpu(p)); + + if (__is_big_task(p, old_task_load) && !__is_big_task(p, new_task_load)) + stats->nr_big_tasks--; + else if (!__is_big_task(p, old_task_load) && + __is_big_task(p, new_task_load)) + stats->nr_big_tasks++; + + BUG_ON(stats->nr_big_tasks < 0); +} + +/* + * Walk runqueue of cpu and re-initialize 'nr_big_tasks' counters. + */ +static void update_nr_big_tasks(int cpu) +{ + struct rq *rq = cpu_rq(cpu); + struct task_struct *p; + + /* Do not reset cumulative_runnable_avg */ + reset_cpu_hmp_stats(cpu, 0); + + list_for_each_entry(p, &rq->cfs_tasks, se.group_node) + _inc_hmp_sched_stats_fair(rq, p, 0); +} + +/* Disable interrupts and grab runqueue lock of all cpus listed in @cpus */ +void pre_big_task_count_change(const struct cpumask *cpus) +{ + int i; + + local_irq_disable(); + + for_each_cpu(i, cpus) + raw_spin_lock(&cpu_rq(i)->lock); +} + +/* + * Reinitialize 'nr_big_tasks' counters on all affected cpus + */ +void post_big_task_count_change(const struct cpumask *cpus) +{ + int i; + + /* Assumes local_irq_disable() keeps online cpumap stable */ + for_each_cpu(i, cpus) + update_nr_big_tasks(i); + + for_each_cpu(i, cpus) + raw_spin_unlock(&cpu_rq(i)->lock); + + local_irq_enable(); +} + +DEFINE_MUTEX(policy_mutex); + +unsigned int update_freq_aggregate_threshold(unsigned int threshold) +{ + unsigned int old_threshold; + + mutex_lock(&policy_mutex); + + old_threshold = sysctl_sched_freq_aggregate_threshold_pct; + + sysctl_sched_freq_aggregate_threshold_pct = threshold; + sched_freq_aggregate_threshold = + pct_to_real(sysctl_sched_freq_aggregate_threshold_pct); + + mutex_unlock(&policy_mutex); + + return old_threshold; +} + +static inline int invalid_value_freq_input(unsigned int *data) +{ + if (data == &sysctl_sched_freq_aggregate) + return !(*data == 0 || *data == 1); + + return 0; +} + +static inline int invalid_value(unsigned int *data) +{ + unsigned int val = *data; + + if (data == &sysctl_sched_ravg_hist_size) + return (val < 2 || val > RAVG_HIST_SIZE_MAX); + + if (data == &sysctl_sched_window_stats_policy) + return val >= WINDOW_STATS_INVALID_POLICY; + + return invalid_value_freq_input(data); +} + +/* + * Handle "atomic" update of sysctl_sched_window_stats_policy, + * sysctl_sched_ravg_hist_size variables. + */ +int sched_window_update_handler(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, + loff_t *ppos) +{ + int ret; + unsigned int *data = (unsigned int *)table->data; + unsigned int old_val; + + mutex_lock(&policy_mutex); + + old_val = *data; + + ret = proc_dointvec(table, write, buffer, lenp, ppos); + if (ret || !write || (write && (old_val == *data))) + goto done; + + if (invalid_value(data)) { + *data = old_val; + ret = -EINVAL; + goto done; + } + + reset_all_window_stats(0, 0); + +done: + mutex_unlock(&policy_mutex); + + return ret; +} + +/* + * Convert percentage value into absolute form. This will avoid div() operation + * in fast path, to convert task load in percentage scale. + */ +int sched_hmp_proc_update_handler(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, + loff_t *ppos) +{ + int ret; + unsigned int old_val; + unsigned int *data = (unsigned int *)table->data; + int update_task_count = 0; + + /* + * The policy mutex is acquired with cpu_hotplug.lock + * held from cpu_up()->cpufreq_governor_interactive()-> + * sched_set_window(). So enforce the same order here. + */ + if (write && (data == &sysctl_sched_upmigrate_pct)) { + update_task_count = 1; + get_online_cpus(); + } + + mutex_lock(&policy_mutex); + + old_val = *data; + + ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); + + if (ret || !write) + goto done; + + if (write && (old_val == *data)) + goto done; + + if (sysctl_sched_downmigrate_pct > sysctl_sched_upmigrate_pct || + sysctl_sched_group_downmigrate_pct > + sysctl_sched_group_upmigrate_pct) { + *data = old_val; + ret = -EINVAL; + goto done; + } + + /* + * Big task tunable change will need to re-classify tasks on + * runqueue as big and set their counters appropriately. + * sysctl interface affects secondary variables (*_pct), which is then + * "atomically" carried over to the primary variables. Atomic change + * includes taking runqueue lock of all online cpus and re-initiatizing + * their big counter values based on changed criteria. + */ + if (update_task_count) + pre_big_task_count_change(cpu_online_mask); + + set_hmp_defaults(); + + if (update_task_count) + post_big_task_count_change(cpu_online_mask); + +done: + mutex_unlock(&policy_mutex); + if (update_task_count) + put_online_cpus(); + return ret; +} + +inline int nr_big_tasks(struct rq *rq) +{ + return rq->hmp_stats.nr_big_tasks; +} + +unsigned int cpu_temp(int cpu) +{ + struct cpu_pwr_stats *per_cpu_info = get_cpu_pwr_stats(); + + if (per_cpu_info) + return per_cpu_info[cpu].temp; + else + return 0; +} + +/* + * kfree() may wakeup kswapd. So this function should NOT be called + * with any CPU's rq->lock acquired. + */ +void free_task_load_ptrs(struct task_struct *p) +{ + kfree(p->ravg.curr_window_cpu); + kfree(p->ravg.prev_window_cpu); + + /* + * update_task_ravg() can be called for exiting tasks. While the + * function itself ensures correct behavior, the corresponding + * trace event requires that these pointers be NULL. + */ + p->ravg.curr_window_cpu = NULL; + p->ravg.prev_window_cpu = NULL; +} + +void init_new_task_load(struct task_struct *p) +{ + int i; + u32 init_load_windows = sched_init_task_load_windows; + u32 init_load_pct = current->init_load_pct; + + p->init_load_pct = 0; + rcu_assign_pointer(p->grp, NULL); + INIT_LIST_HEAD(&p->grp_list); + memset(&p->ravg, 0, sizeof(struct ravg)); + p->cpu_cycles = 0; + p->ravg.curr_burst = 0; + /* + * Initialize the avg_burst to twice the threshold, so that + * a task would not be classified as short burst right away + * after fork. It takes at least 6 sleep-wakeup cycles for + * the avg_burst to go below the threshold. + */ + p->ravg.avg_burst = 2 * (u64)sysctl_sched_short_burst; + p->ravg.avg_sleep_time = 0; + + p->ravg.curr_window_cpu = kcalloc(nr_cpu_ids, sizeof(u32), GFP_KERNEL); + p->ravg.prev_window_cpu = kcalloc(nr_cpu_ids, sizeof(u32), GFP_KERNEL); + + /* Don't have much choice. CPU frequency would be bogus */ + BUG_ON(!p->ravg.curr_window_cpu || !p->ravg.prev_window_cpu); + + if (init_load_pct) + init_load_windows = div64_u64((u64)init_load_pct * + (u64)sched_ravg_window, 100); + + p->ravg.demand = init_load_windows; + p->ravg.pred_demand = 0; + for (i = 0; i < RAVG_HIST_SIZE_MAX; ++i) + p->ravg.sum_history[i] = init_load_windows; +} + +/* Return task demand in percentage scale */ +unsigned int pct_task_load(struct task_struct *p) +{ + unsigned int load; + + load = div64_u64((u64)task_load(p) * 100, (u64)max_task_load()); + + return load; +} + +/* + * Return total number of tasks "eligible" to run on highest capacity cpu + * + * This is simply nr_big_tasks for cpus which are not of max_capacity and + * nr_running for cpus of max_capacity + */ +unsigned int nr_eligible_big_tasks(int cpu) +{ + struct rq *rq = cpu_rq(cpu); + int nr_big = rq->hmp_stats.nr_big_tasks; + int nr = rq->nr_running; + + if (!is_max_capacity_cpu(cpu)) + return nr_big; + + return nr; +} + +static inline int exiting_task(struct task_struct *p) +{ + return (p->ravg.sum_history[0] == EXITING_TASK_MARKER); +} + +static int __init set_sched_ravg_window(char *str) +{ + unsigned int window_size; + + get_option(&str, &window_size); + + if (window_size < MIN_SCHED_RAVG_WINDOW || + window_size > MAX_SCHED_RAVG_WINDOW) { + WARN_ON(1); + return -EINVAL; + } + + sched_ravg_window = window_size; + return 0; +} + +early_param("sched_ravg_window", set_sched_ravg_window); + +static inline void +update_window_start(struct rq *rq, u64 wallclock) +{ + s64 delta; + int nr_windows; + + delta = wallclock - rq->window_start; + BUG_ON(delta < 0); + if (delta < sched_ravg_window) + return; + + nr_windows = div64_u64(delta, sched_ravg_window); + rq->window_start += (u64)nr_windows * (u64)sched_ravg_window; +} + +#define DIV64_U64_ROUNDUP(X, Y) div64_u64((X) + (Y - 1), Y) + +static inline u64 scale_exec_time(u64 delta, struct rq *rq) +{ + u32 freq; + + freq = cpu_cycles_to_freq(rq->cc.cycles, rq->cc.time); + delta = DIV64_U64_ROUNDUP(delta * freq, max_possible_freq); + delta *= rq->cluster->exec_scale_factor; + delta >>= 10; + + return delta; +} + +static inline int cpu_is_waiting_on_io(struct rq *rq) +{ + if (!sched_io_is_busy) + return 0; + + return atomic_read(&rq->nr_iowait); +} + +/* Does freq_required sufficiently exceed or fall behind cur_freq? */ +static inline int +nearly_same_freq(unsigned int cur_freq, unsigned int freq_required) +{ + int delta = freq_required - cur_freq; + + if (freq_required > cur_freq) + return delta < sysctl_sched_freq_inc_notify; + + delta = -delta; + + return delta < sysctl_sched_freq_dec_notify; +} + +/* Convert busy time to frequency equivalent */ +static inline unsigned int load_to_freq(struct rq *rq, u64 load) +{ + unsigned int freq; + + load = scale_load_to_cpu(load, cpu_of(rq)); + load *= 128; + load = div64_u64(load, max_task_load()); + + freq = load * cpu_max_possible_freq(cpu_of(rq)); + freq /= 128; + + return freq; +} + +/* + * Return load from all related groups in given frequency domain. + */ +static void group_load_in_freq_domain(struct cpumask *cpus, + u64 *grp_load, u64 *new_grp_load) +{ + int j; + + for_each_cpu(j, cpus) { + struct rq *rq = cpu_rq(j); + + *grp_load += rq->grp_time.prev_runnable_sum; + *new_grp_load += rq->grp_time.nt_prev_runnable_sum; + } +} + +static inline u64 freq_policy_load(struct rq *rq, u64 load); +/* + * Should scheduler alert governor for changing frequency? + * + * @check_pred - evaluate frequency based on the predictive demand + * @check_groups - add load from all related groups on given cpu + * + * check_groups is set to 1 if a "related" task movement/wakeup is triggering + * the notification check. To avoid "re-aggregation" of demand in such cases, + * we check whether the migrated/woken tasks demand (along with demand from + * existing tasks on the cpu) can be met on target cpu + * + */ + +static int send_notification(struct rq *rq, int check_pred, int check_groups) +{ + unsigned int cur_freq, freq_required; + unsigned long flags; + int rc = 0; + u64 group_load = 0, new_load = 0; + + if (check_pred) { + u64 prev = rq->old_busy_time; + u64 predicted = rq->hmp_stats.pred_demands_sum; + + if (rq->cluster->cur_freq == cpu_max_freq(cpu_of(rq))) + return 0; + + prev = max(prev, rq->old_estimated_time); + if (prev > predicted) + return 0; + + cur_freq = load_to_freq(rq, prev); + freq_required = load_to_freq(rq, predicted); + + if (freq_required < cur_freq + sysctl_sched_pred_alert_freq) + return 0; + } else { + /* + * Protect from concurrent update of rq->prev_runnable_sum and + * group cpu load + */ + raw_spin_lock_irqsave(&rq->lock, flags); + if (check_groups) + group_load = rq->grp_time.prev_runnable_sum; + + new_load = rq->prev_runnable_sum + group_load; + new_load = freq_policy_load(rq, new_load); + + raw_spin_unlock_irqrestore(&rq->lock, flags); + + cur_freq = load_to_freq(rq, rq->old_busy_time); + freq_required = load_to_freq(rq, new_load); + + if (nearly_same_freq(cur_freq, freq_required)) + return 0; + } + + raw_spin_lock_irqsave(&rq->lock, flags); + if (!rq->cluster->notifier_sent) { + rq->cluster->notifier_sent = 1; + rc = 1; + trace_sched_freq_alert(cpu_of(rq), check_pred, check_groups, rq, + new_load); + } + raw_spin_unlock_irqrestore(&rq->lock, flags); + + return rc; +} + +/* Alert governor if there is a need to change frequency */ +void check_for_freq_change(struct rq *rq, bool check_pred, bool check_groups) +{ + int cpu = cpu_of(rq); + + if (!send_notification(rq, check_pred, check_groups)) + return; + + atomic_notifier_call_chain( + &load_alert_notifier_head, 0, + (void *)(long)cpu); +} + +void notify_migration(int src_cpu, int dest_cpu, bool src_cpu_dead, + struct task_struct *p) +{ + bool check_groups; + + rcu_read_lock(); + check_groups = task_in_related_thread_group(p); + rcu_read_unlock(); + + if (!same_freq_domain(src_cpu, dest_cpu)) { + if (!src_cpu_dead) + check_for_freq_change(cpu_rq(src_cpu), false, + check_groups); + check_for_freq_change(cpu_rq(dest_cpu), false, check_groups); + } else { + check_for_freq_change(cpu_rq(dest_cpu), true, check_groups); + } +} + +static int account_busy_for_cpu_time(struct rq *rq, struct task_struct *p, + u64 irqtime, int event) +{ + if (is_idle_task(p)) { + /* TASK_WAKE && TASK_MIGRATE is not possible on idle task! */ + if (event == PICK_NEXT_TASK) + return 0; + + /* PUT_PREV_TASK, TASK_UPDATE && IRQ_UPDATE are left */ + return irqtime || cpu_is_waiting_on_io(rq); + } + + if (event == TASK_WAKE) + return 0; + + if (event == PUT_PREV_TASK || event == IRQ_UPDATE) + return 1; + + /* + * TASK_UPDATE can be called on sleeping task, when its moved between + * related groups + */ + if (event == TASK_UPDATE) { + if (rq->curr == p) + return 1; + + return p->on_rq ? SCHED_FREQ_ACCOUNT_WAIT_TIME : 0; + } + + /* TASK_MIGRATE, PICK_NEXT_TASK left */ + return SCHED_FREQ_ACCOUNT_WAIT_TIME; +} + +static inline bool is_new_task(struct task_struct *p) +{ + return p->ravg.active_windows < SCHED_NEW_TASK_WINDOWS; +} + +#define INC_STEP 8 +#define DEC_STEP 2 +#define CONSISTENT_THRES 16 +#define INC_STEP_BIG 16 +/* + * bucket_increase - update the count of all buckets + * + * @buckets: array of buckets tracking busy time of a task + * @idx: the index of bucket to be incremented + * + * Each time a complete window finishes, count of bucket that runtime + * falls in (@idx) is incremented. Counts of all other buckets are + * decayed. The rate of increase and decay could be different based + * on current count in the bucket. + */ +static inline void bucket_increase(u8 *buckets, int idx) +{ + int i, step; + + for (i = 0; i < NUM_BUSY_BUCKETS; i++) { + if (idx != i) { + if (buckets[i] > DEC_STEP) + buckets[i] -= DEC_STEP; + else + buckets[i] = 0; + } else { + step = buckets[i] >= CONSISTENT_THRES ? + INC_STEP_BIG : INC_STEP; + if (buckets[i] > U8_MAX - step) + buckets[i] = U8_MAX; + else + buckets[i] += step; + } + } +} + +static inline int busy_to_bucket(u32 normalized_rt) +{ + int bidx; + + bidx = mult_frac(normalized_rt, NUM_BUSY_BUCKETS, max_task_load()); + bidx = min(bidx, NUM_BUSY_BUCKETS - 1); + + /* + * Combine lowest two buckets. The lowest frequency falls into + * 2nd bucket and thus keep predicting lowest bucket is not + * useful. + */ + if (!bidx) + bidx++; + + return bidx; +} + +static inline u64 +scale_load_to_freq(u64 load, unsigned int src_freq, unsigned int dst_freq) +{ + return div64_u64(load * (u64)src_freq, (u64)dst_freq); +} + +/* + * get_pred_busy - calculate predicted demand for a task on runqueue + * + * @rq: runqueue of task p + * @p: task whose prediction is being updated + * @start: starting bucket. returned prediction should not be lower than + * this bucket. + * @runtime: runtime of the task. returned prediction should not be lower + * than this runtime. + * Note: @start can be derived from @runtime. It's passed in only to + * avoid duplicated calculation in some cases. + * + * A new predicted busy time is returned for task @p based on @runtime + * passed in. The function searches through buckets that represent busy + * time equal to or bigger than @runtime and attempts to find the bucket to + * to use for prediction. Once found, it searches through historical busy + * time and returns the latest that falls into the bucket. If no such busy + * time exists, it returns the medium of that bucket. + */ +static u32 get_pred_busy(struct rq *rq, struct task_struct *p, + int start, u32 runtime) +{ + int i; + u8 *buckets = p->ravg.busy_buckets; + u32 *hist = p->ravg.sum_history; + u32 dmin, dmax; + u64 cur_freq_runtime = 0; + int first = NUM_BUSY_BUCKETS, final; + u32 ret = runtime; + + /* skip prediction for new tasks due to lack of history */ + if (unlikely(is_new_task(p))) + goto out; + + /* find minimal bucket index to pick */ + for (i = start; i < NUM_BUSY_BUCKETS; i++) { + if (buckets[i]) { + first = i; + break; + } + } + /* if no higher buckets are filled, predict runtime */ + if (first >= NUM_BUSY_BUCKETS) + goto out; + + /* compute the bucket for prediction */ + final = first; + + /* determine demand range for the predicted bucket */ + if (final < 2) { + /* lowest two buckets are combined */ + dmin = 0; + final = 1; + } else { + dmin = mult_frac(final, max_task_load(), NUM_BUSY_BUCKETS); + } + dmax = mult_frac(final + 1, max_task_load(), NUM_BUSY_BUCKETS); + + /* + * search through runtime history and return first runtime that falls + * into the range of predicted bucket. + */ + for (i = 0; i < sched_ravg_hist_size; i++) { + if (hist[i] >= dmin && hist[i] < dmax) { + ret = hist[i]; + break; + } + } + /* no historical runtime within bucket found, use average of the bin */ + if (ret < dmin) + ret = (dmin + dmax) / 2; + /* + * when updating in middle of a window, runtime could be higher + * than all recorded history. Always predict at least runtime. + */ + ret = max(runtime, ret); +out: + trace_sched_update_pred_demand(rq, p, runtime, + mult_frac((unsigned int)cur_freq_runtime, 100, + sched_ravg_window), ret); + return ret; +} + +static inline u32 calc_pred_demand(struct rq *rq, struct task_struct *p) +{ + if (p->ravg.pred_demand >= p->ravg.curr_window) + return p->ravg.pred_demand; + + return get_pred_busy(rq, p, busy_to_bucket(p->ravg.curr_window), + p->ravg.curr_window); +} + +/* + * predictive demand of a task is calculated at the window roll-over. + * if the task current window busy time exceeds the predicted + * demand, update it here to reflect the task needs. + */ +void update_task_pred_demand(struct rq *rq, struct task_struct *p, int event) +{ + u32 new, old; + + if (is_idle_task(p) || exiting_task(p)) + return; + + if (event != PUT_PREV_TASK && event != TASK_UPDATE && + (!SCHED_FREQ_ACCOUNT_WAIT_TIME || + (event != TASK_MIGRATE && + event != PICK_NEXT_TASK))) + return; + + /* + * TASK_UPDATE can be called on sleeping task, when its moved between + * related groups + */ + if (event == TASK_UPDATE) { + if (!p->on_rq && !SCHED_FREQ_ACCOUNT_WAIT_TIME) + return; + } + + new = calc_pred_demand(rq, p); + old = p->ravg.pred_demand; + + if (old >= new) + return; + + if (task_on_rq_queued(p) && (!task_has_dl_policy(p) || + !p->dl.dl_throttled)) + p->sched_class->fixup_hmp_sched_stats(rq, p, + p->ravg.demand, + new); + + p->ravg.pred_demand = new; +} + +void clear_top_tasks_bitmap(unsigned long *bitmap) +{ + memset(bitmap, 0, top_tasks_bitmap_size); + __set_bit(NUM_LOAD_INDICES, bitmap); +} + +/* + * Special case the last index and provide a fast path for index = 0. + * Note that sched_load_granule can change underneath us if we are not + * holding any runqueue locks while calling the two functions below. + */ +static u32 top_task_load(struct rq *rq) +{ + int index = rq->prev_top; + u8 prev = 1 - rq->curr_table; + + if (!index) { + int msb = NUM_LOAD_INDICES - 1; + + if (!test_bit(msb, rq->top_tasks_bitmap[prev])) + return 0; + else + return sched_load_granule; + } else if (index == NUM_LOAD_INDICES - 1) { + return sched_ravg_window; + } else { + return (index + 1) * sched_load_granule; + } +} + +static u32 load_to_index(u32 load) +{ + u32 index = load / sched_load_granule; + + return min(index, (u32)(NUM_LOAD_INDICES - 1)); +} + +static void update_top_tasks(struct task_struct *p, struct rq *rq, + u32 old_curr_window, int new_window, bool full_window) +{ + u8 curr = rq->curr_table; + u8 prev = 1 - curr; + u8 *curr_table = rq->top_tasks[curr]; + u8 *prev_table = rq->top_tasks[prev]; + int old_index, new_index, update_index; + u32 curr_window = p->ravg.curr_window; + u32 prev_window = p->ravg.prev_window; + bool zero_index_update; + + if (old_curr_window == curr_window && !new_window) + return; + + old_index = load_to_index(old_curr_window); + new_index = load_to_index(curr_window); + + if (!new_window) { + zero_index_update = !old_curr_window && curr_window; + if (old_index != new_index || zero_index_update) { + if (old_curr_window) + curr_table[old_index] -= 1; + if (curr_window) + curr_table[new_index] += 1; + if (new_index > rq->curr_top) + rq->curr_top = new_index; + } + + if (!curr_table[old_index]) + __clear_bit(NUM_LOAD_INDICES - old_index - 1, + rq->top_tasks_bitmap[curr]); + + if (curr_table[new_index] == 1) + __set_bit(NUM_LOAD_INDICES - new_index - 1, + rq->top_tasks_bitmap[curr]); + + return; + } + + /* + * The window has rolled over for this task. By the time we get + * here, curr/prev swaps would has already occurred. So we need + * to use prev_window for the new index. + */ + update_index = load_to_index(prev_window); + + if (full_window) { + /* + * Two cases here. Either 'p' ran for the entire window or + * it didn't run at all. In either case there is no entry + * in the prev table. If 'p' ran the entire window, we just + * need to create a new entry in the prev table. In this case + * update_index will be correspond to sched_ravg_window + * so we can unconditionally update the top index. + */ + if (prev_window) { + prev_table[update_index] += 1; + rq->prev_top = update_index; + } + + if (prev_table[update_index] == 1) + __set_bit(NUM_LOAD_INDICES - update_index - 1, + rq->top_tasks_bitmap[prev]); + } else { + zero_index_update = !old_curr_window && prev_window; + if (old_index != update_index || zero_index_update) { + if (old_curr_window) + prev_table[old_index] -= 1; + + prev_table[update_index] += 1; + + if (update_index > rq->prev_top) + rq->prev_top = update_index; + + if (!prev_table[old_index]) + __clear_bit(NUM_LOAD_INDICES - old_index - 1, + rq->top_tasks_bitmap[prev]); + + if (prev_table[update_index] == 1) + __set_bit(NUM_LOAD_INDICES - update_index - 1, + rq->top_tasks_bitmap[prev]); + } + } + + if (curr_window) { + curr_table[new_index] += 1; + + if (new_index > rq->curr_top) + rq->curr_top = new_index; + + if (curr_table[new_index] == 1) + __set_bit(NUM_LOAD_INDICES - new_index - 1, + rq->top_tasks_bitmap[curr]); + } +} + +static inline void clear_top_tasks_table(u8 *table) +{ + memset(table, 0, NUM_LOAD_INDICES * sizeof(u8)); +} + +static void rollover_top_tasks(struct rq *rq, bool full_window) +{ + u8 curr_table = rq->curr_table; + u8 prev_table = 1 - curr_table; + int curr_top = rq->curr_top; + + clear_top_tasks_table(rq->top_tasks[prev_table]); + clear_top_tasks_bitmap(rq->top_tasks_bitmap[prev_table]); + + if (full_window) { + curr_top = 0; + clear_top_tasks_table(rq->top_tasks[curr_table]); + clear_top_tasks_bitmap( + rq->top_tasks_bitmap[curr_table]); + } + + rq->curr_table = prev_table; + rq->prev_top = curr_top; + rq->curr_top = 0; +} + +static u32 empty_windows[NR_CPUS]; + +static void rollover_task_window(struct task_struct *p, bool full_window) +{ + u32 *curr_cpu_windows = empty_windows; + u32 curr_window; + int i; + + /* Rollover the sum */ + curr_window = 0; + + if (!full_window) { + curr_window = p->ravg.curr_window; + curr_cpu_windows = p->ravg.curr_window_cpu; + } + + p->ravg.prev_window = curr_window; + p->ravg.curr_window = 0; + + /* Roll over individual CPU contributions */ + for (i = 0; i < nr_cpu_ids; i++) { + p->ravg.prev_window_cpu[i] = curr_cpu_windows[i]; + p->ravg.curr_window_cpu[i] = 0; + } +} + +static void rollover_cpu_window(struct rq *rq, bool full_window) +{ + u64 curr_sum = rq->curr_runnable_sum; + u64 nt_curr_sum = rq->nt_curr_runnable_sum; + u64 grp_curr_sum = rq->grp_time.curr_runnable_sum; + u64 grp_nt_curr_sum = rq->grp_time.nt_curr_runnable_sum; + + if (unlikely(full_window)) { + curr_sum = 0; + nt_curr_sum = 0; + grp_curr_sum = 0; + grp_nt_curr_sum = 0; + } + + rq->prev_runnable_sum = curr_sum; + rq->nt_prev_runnable_sum = nt_curr_sum; + rq->grp_time.prev_runnable_sum = grp_curr_sum; + rq->grp_time.nt_prev_runnable_sum = grp_nt_curr_sum; + + rq->curr_runnable_sum = 0; + rq->nt_curr_runnable_sum = 0; + rq->grp_time.curr_runnable_sum = 0; + rq->grp_time.nt_curr_runnable_sum = 0; +} + +/* + * Account cpu activity in its busy time counters (rq->curr/prev_runnable_sum) + */ +static void update_cpu_busy_time(struct task_struct *p, struct rq *rq, + int event, u64 wallclock, u64 irqtime) +{ + int new_window, full_window = 0; + int p_is_curr_task = (p == rq->curr); + u64 mark_start = p->ravg.mark_start; + u64 window_start = rq->window_start; + u32 window_size = sched_ravg_window; + u64 delta; + u64 *curr_runnable_sum = &rq->curr_runnable_sum; + u64 *prev_runnable_sum = &rq->prev_runnable_sum; + u64 *nt_curr_runnable_sum = &rq->nt_curr_runnable_sum; + u64 *nt_prev_runnable_sum = &rq->nt_prev_runnable_sum; + bool new_task; + struct related_thread_group *grp; + int cpu = rq->cpu; + u32 old_curr_window = p->ravg.curr_window; + + new_window = mark_start < window_start; + if (new_window) { + full_window = (window_start - mark_start) >= window_size; + if (p->ravg.active_windows < USHRT_MAX) + p->ravg.active_windows++; + } + + new_task = is_new_task(p); + + /* + * Handle per-task window rollover. We don't care about the idle + * task or exiting tasks. + */ + if (!is_idle_task(p) && !exiting_task(p)) { + if (new_window) + rollover_task_window(p, full_window); + } + + if (p_is_curr_task && new_window) { + rollover_cpu_window(rq, full_window); + rollover_top_tasks(rq, full_window); + } + + if (!account_busy_for_cpu_time(rq, p, irqtime, event)) + goto done; + + grp = p->grp; + if (grp && sched_freq_aggregate) { + struct group_cpu_time *cpu_time = &rq->grp_time; + + curr_runnable_sum = &cpu_time->curr_runnable_sum; + prev_runnable_sum = &cpu_time->prev_runnable_sum; + + nt_curr_runnable_sum = &cpu_time->nt_curr_runnable_sum; + nt_prev_runnable_sum = &cpu_time->nt_prev_runnable_sum; + } + + if (!new_window) { + /* + * account_busy_for_cpu_time() = 1 so busy time needs + * to be accounted to the current window. No rollover + * since we didn't start a new window. An example of this is + * when a task starts execution and then sleeps within the + * same window. + */ + + if (!irqtime || !is_idle_task(p) || cpu_is_waiting_on_io(rq)) + delta = wallclock - mark_start; + else + delta = irqtime; + delta = scale_exec_time(delta, rq); + *curr_runnable_sum += delta; + if (new_task) + *nt_curr_runnable_sum += delta; + + if (!is_idle_task(p) && !exiting_task(p)) { + p->ravg.curr_window += delta; + p->ravg.curr_window_cpu[cpu] += delta; + } + + goto done; + } + + if (!p_is_curr_task) { + /* + * account_busy_for_cpu_time() = 1 so busy time needs + * to be accounted to the current window. A new window + * has also started, but p is not the current task, so the + * window is not rolled over - just split up and account + * as necessary into curr and prev. The window is only + * rolled over when a new window is processed for the current + * task. + * + * Irqtime can't be accounted by a task that isn't the + * currently running task. + */ + + if (!full_window) { + /* + * A full window hasn't elapsed, account partial + * contribution to previous completed window. + */ + delta = scale_exec_time(window_start - mark_start, rq); + if (!exiting_task(p)) { + p->ravg.prev_window += delta; + p->ravg.prev_window_cpu[cpu] += delta; + } + } else { + /* + * Since at least one full window has elapsed, + * the contribution to the previous window is the + * full window (window_size). + */ + delta = scale_exec_time(window_size, rq); + if (!exiting_task(p)) { + p->ravg.prev_window = delta; + p->ravg.prev_window_cpu[cpu] = delta; + } + } + + *prev_runnable_sum += delta; + if (new_task) + *nt_prev_runnable_sum += delta; + + /* Account piece of busy time in the current window. */ + delta = scale_exec_time(wallclock - window_start, rq); + *curr_runnable_sum += delta; + if (new_task) + *nt_curr_runnable_sum += delta; + + if (!exiting_task(p)) { + p->ravg.curr_window = delta; + p->ravg.curr_window_cpu[cpu] = delta; + } + + goto done; + } + + if (!irqtime || !is_idle_task(p) || cpu_is_waiting_on_io(rq)) { + /* + * account_busy_for_cpu_time() = 1 so busy time needs + * to be accounted to the current window. A new window + * has started and p is the current task so rollover is + * needed. If any of these three above conditions are true + * then this busy time can't be accounted as irqtime. + * + * Busy time for the idle task or exiting tasks need not + * be accounted. + * + * An example of this would be a task that starts execution + * and then sleeps once a new window has begun. + */ + + if (!full_window) { + /* + * A full window hasn't elapsed, account partial + * contribution to previous completed window. + */ + delta = scale_exec_time(window_start - mark_start, rq); + if (!is_idle_task(p) && !exiting_task(p)) { + p->ravg.prev_window += delta; + p->ravg.prev_window_cpu[cpu] += delta; + } + } else { + /* + * Since at least one full window has elapsed, + * the contribution to the previous window is the + * full window (window_size). + */ + delta = scale_exec_time(window_size, rq); + if (!is_idle_task(p) && !exiting_task(p)) { + p->ravg.prev_window = delta; + p->ravg.prev_window_cpu[cpu] = delta; + } + } + + /* + * Rollover is done here by overwriting the values in + * prev_runnable_sum and curr_runnable_sum. + */ + *prev_runnable_sum += delta; + if (new_task) + *nt_prev_runnable_sum += delta; + + /* Account piece of busy time in the current window. */ + delta = scale_exec_time(wallclock - window_start, rq); + *curr_runnable_sum += delta; + if (new_task) + *nt_curr_runnable_sum += delta; + + if (!is_idle_task(p) && !exiting_task(p)) { + p->ravg.curr_window = delta; + p->ravg.curr_window_cpu[cpu] = delta; + } + + goto done; + } + + if (irqtime) { + /* + * account_busy_for_cpu_time() = 1 so busy time needs + * to be accounted to the current window. A new window + * has started and p is the current task so rollover is + * needed. The current task must be the idle task because + * irqtime is not accounted for any other task. + * + * Irqtime will be accounted each time we process IRQ activity + * after a period of idleness, so we know the IRQ busy time + * started at wallclock - irqtime. + */ + + BUG_ON(!is_idle_task(p)); + mark_start = wallclock - irqtime; + + /* + * Roll window over. If IRQ busy time was just in the current + * window then that is all that need be accounted. + */ + if (mark_start > window_start) { + *curr_runnable_sum = scale_exec_time(irqtime, rq); + return; + } + + /* + * The IRQ busy time spanned multiple windows. Process the + * busy time preceding the current window start first. + */ + delta = window_start - mark_start; + if (delta > window_size) + delta = window_size; + delta = scale_exec_time(delta, rq); + *prev_runnable_sum += delta; + + /* Process the remaining IRQ busy time in the current window. */ + delta = wallclock - window_start; + rq->curr_runnable_sum = scale_exec_time(delta, rq); + + return; + } + +done: + if (!is_idle_task(p) && !exiting_task(p)) + update_top_tasks(p, rq, old_curr_window, + new_window, full_window); +} + +static inline u32 predict_and_update_buckets(struct rq *rq, + struct task_struct *p, u32 runtime) { + + int bidx; + u32 pred_demand; + + bidx = busy_to_bucket(runtime); + pred_demand = get_pred_busy(rq, p, bidx, runtime); + bucket_increase(p->ravg.busy_buckets, bidx); + + return pred_demand; +} + +#define THRESH_CC_UPDATE (2 * NSEC_PER_USEC) + +/* + * Assumes rq_lock is held and wallclock was recorded in the same critical + * section as this function's invocation. + */ +static inline u64 read_cycle_counter(int cpu, u64 wallclock) +{ + struct sched_cluster *cluster = cpu_rq(cpu)->cluster; + u64 delta; + + if (unlikely(!cluster)) + return cpu_cycle_counter_cb.get_cpu_cycle_counter(cpu); + + /* + * Why don't we need locking here? Let's say that delta is negative + * because some other CPU happened to update last_cc_update with a + * more recent timestamp. We simply read the conter again in that case + * with no harmful side effects. This can happen if there is an FIQ + * between when we read the wallclock and when we use it here. + */ + delta = wallclock - atomic64_read(&cluster->last_cc_update); + if (delta > THRESH_CC_UPDATE) { + atomic64_set(&cluster->cycles, + cpu_cycle_counter_cb.get_cpu_cycle_counter(cpu)); + atomic64_set(&cluster->last_cc_update, wallclock); + } + + return atomic64_read(&cluster->cycles); +} + +static void update_task_cpu_cycles(struct task_struct *p, int cpu, + u64 wallclock) +{ + if (use_cycle_counter) + p->cpu_cycles = read_cycle_counter(cpu, wallclock); +} + +static void +update_task_rq_cpu_cycles(struct task_struct *p, struct rq *rq, int event, + u64 wallclock, u64 irqtime) +{ + u64 cur_cycles; + int cpu = cpu_of(rq); + + lockdep_assert_held(&rq->lock); + + if (!use_cycle_counter) { + rq->cc.cycles = cpu_cur_freq(cpu); + rq->cc.time = 1; + return; + } + + cur_cycles = read_cycle_counter(cpu, wallclock); + + /* + * If current task is idle task and irqtime == 0 CPU was + * indeed idle and probably its cycle counter was not + * increasing. We still need estimatied CPU frequency + * for IO wait time accounting. Use the previously + * calculated frequency in such a case. + */ + if (!is_idle_task(rq->curr) || irqtime) { + if (unlikely(cur_cycles < p->cpu_cycles)) + rq->cc.cycles = cur_cycles + (U64_MAX - p->cpu_cycles); + else + rq->cc.cycles = cur_cycles - p->cpu_cycles; + rq->cc.cycles = rq->cc.cycles * NSEC_PER_MSEC; + + if (event == IRQ_UPDATE && is_idle_task(p)) + /* + * Time between mark_start of idle task and IRQ handler + * entry time is CPU cycle counter stall period. + * Upon IRQ handler entry sched_account_irqstart() + * replenishes idle task's cpu cycle counter so + * rq->cc.cycles now represents increased cycles during + * IRQ handler rather than time between idle entry and + * IRQ exit. Thus use irqtime as time delta. + */ + rq->cc.time = irqtime; + else + rq->cc.time = wallclock - p->ravg.mark_start; + BUG_ON((s64)rq->cc.time < 0); + } + + p->cpu_cycles = cur_cycles; + + trace_sched_get_task_cpu_cycles(cpu, event, rq->cc.cycles, + rq->cc.time, p); +} + +static int +account_busy_for_task_demand(struct rq *rq, struct task_struct *p, int event) +{ + /* + * No need to bother updating task demand for exiting tasks + * or the idle task. + */ + if (exiting_task(p) || is_idle_task(p)) + return 0; + + /* + * When a task is waking up it is completing a segment of non-busy + * time. Likewise, if wait time is not treated as busy time, then + * when a task begins to run or is migrated, it is not running and + * is completing a segment of non-busy time. + */ + if (event == TASK_WAKE || (!SCHED_ACCOUNT_WAIT_TIME && + (event == PICK_NEXT_TASK || event == TASK_MIGRATE))) + return 0; + + /* + * TASK_UPDATE can be called on sleeping task, when its moved between + * related groups + */ + if (event == TASK_UPDATE) { + if (rq->curr == p) + return 1; + + return p->on_rq ? SCHED_ACCOUNT_WAIT_TIME : 0; + } + + return 1; +} + +/* + * Called when new window is starting for a task, to record cpu usage over + * recently concluded window(s). Normally 'samples' should be 1. It can be > 1 + * when, say, a real-time task runs without preemption for several windows at a + * stretch. + */ +static void update_history(struct rq *rq, struct task_struct *p, + u32 runtime, int samples, int event) +{ + u32 *hist = &p->ravg.sum_history[0]; + int ridx, widx; + u32 max = 0, avg, demand, pred_demand; + u64 sum = 0; + + /* Ignore windows where task had no activity */ + if (!runtime || is_idle_task(p) || exiting_task(p) || !samples) + goto done; + + /* Push new 'runtime' value onto stack */ + widx = sched_ravg_hist_size - 1; + ridx = widx - samples; + for (; ridx >= 0; --widx, --ridx) { + hist[widx] = hist[ridx]; + sum += hist[widx]; + if (hist[widx] > max) + max = hist[widx]; + } + + for (widx = 0; widx < samples && widx < sched_ravg_hist_size; widx++) { + hist[widx] = runtime; + sum += hist[widx]; + if (hist[widx] > max) + max = hist[widx]; + } + + p->ravg.sum = 0; + + if (sched_window_stats_policy == WINDOW_STATS_RECENT) { + demand = runtime; + } else if (sched_window_stats_policy == WINDOW_STATS_MAX) { + demand = max; + } else { + avg = div64_u64(sum, sched_ravg_hist_size); + if (sched_window_stats_policy == WINDOW_STATS_AVG) + demand = avg; + else + demand = max(avg, runtime); + } + pred_demand = predict_and_update_buckets(rq, p, runtime); + + /* + * A throttled deadline sched class task gets dequeued without + * changing p->on_rq. Since the dequeue decrements hmp stats + * avoid decrementing it here again. + */ + if (task_on_rq_queued(p) && (!task_has_dl_policy(p) || + !p->dl.dl_throttled)) + p->sched_class->fixup_hmp_sched_stats(rq, p, demand, + pred_demand); + + p->ravg.demand = demand; + p->ravg.pred_demand = pred_demand; + +done: + trace_sched_update_history(rq, p, runtime, samples, event); +} + +static u64 add_to_task_demand(struct rq *rq, struct task_struct *p, u64 delta) +{ + delta = scale_exec_time(delta, rq); + p->ravg.sum += delta; + if (unlikely(p->ravg.sum > sched_ravg_window)) + p->ravg.sum = sched_ravg_window; + + return delta; +} + +/* + * Account cpu demand of task and/or update task's cpu demand history + * + * ms = p->ravg.mark_start; + * wc = wallclock + * ws = rq->window_start + * + * Three possibilities: + * + * a) Task event is contained within one window. + * window_start < mark_start < wallclock + * + * ws ms wc + * | | | + * V V V + * |---------------| + * + * In this case, p->ravg.sum is updated *iff* event is appropriate + * (ex: event == PUT_PREV_TASK) + * + * b) Task event spans two windows. + * mark_start < window_start < wallclock + * + * ms ws wc + * | | | + * V V V + * -----|------------------- + * + * In this case, p->ravg.sum is updated with (ws - ms) *iff* event + * is appropriate, then a new window sample is recorded followed + * by p->ravg.sum being set to (wc - ws) *iff* event is appropriate. + * + * c) Task event spans more than two windows. + * + * ms ws_tmp ws wc + * | | | | + * V V V V + * ---|-------|-------|-------|-------|------ + * | | + * |<------ nr_full_windows ------>| + * + * In this case, p->ravg.sum is updated with (ws_tmp - ms) first *iff* + * event is appropriate, window sample of p->ravg.sum is recorded, + * 'nr_full_window' samples of window_size is also recorded *iff* + * event is appropriate and finally p->ravg.sum is set to (wc - ws) + * *iff* event is appropriate. + * + * IMPORTANT : Leave p->ravg.mark_start unchanged, as update_cpu_busy_time() + * depends on it! + */ +static u64 update_task_demand(struct task_struct *p, struct rq *rq, + int event, u64 wallclock) +{ + u64 mark_start = p->ravg.mark_start; + u64 delta, window_start = rq->window_start; + int new_window, nr_full_windows; + u32 window_size = sched_ravg_window; + u64 runtime; + + new_window = mark_start < window_start; + if (!account_busy_for_task_demand(rq, p, event)) { + if (new_window) + /* + * If the time accounted isn't being accounted as + * busy time, and a new window started, only the + * previous window need be closed out with the + * pre-existing demand. Multiple windows may have + * elapsed, but since empty windows are dropped, + * it is not necessary to account those. + */ + update_history(rq, p, p->ravg.sum, 1, event); + return 0; + } + + if (!new_window) { + /* + * The simple case - busy time contained within the existing + * window. + */ + return add_to_task_demand(rq, p, wallclock - mark_start); + } + + /* + * Busy time spans at least two windows. Temporarily rewind + * window_start to first window boundary after mark_start. + */ + delta = window_start - mark_start; + nr_full_windows = div64_u64(delta, window_size); + window_start -= (u64)nr_full_windows * (u64)window_size; + + /* Process (window_start - mark_start) first */ + runtime = add_to_task_demand(rq, p, window_start - mark_start); + + /* Push new sample(s) into task's demand history */ + update_history(rq, p, p->ravg.sum, 1, event); + if (nr_full_windows) { + u64 scaled_window = scale_exec_time(window_size, rq); + + update_history(rq, p, scaled_window, nr_full_windows, event); + runtime += nr_full_windows * scaled_window; + } + + /* + * Roll window_start back to current to process any remainder + * in current window. + */ + window_start += (u64)nr_full_windows * (u64)window_size; + + /* Process (wallclock - window_start) next */ + mark_start = window_start; + runtime += add_to_task_demand(rq, p, wallclock - mark_start); + + return runtime; +} + +static inline void +update_task_burst(struct task_struct *p, struct rq *rq, int event, u64 runtime) +{ + /* + * update_task_demand() has checks for idle task and + * exit task. The runtime may include the wait time, + * so update the burst only for the cases where the + * task is running. + */ + if (event == PUT_PREV_TASK || (event == TASK_UPDATE && + rq->curr == p)) + p->ravg.curr_burst += runtime; +} + +/* Reflect task activity on its demand and cpu's busy time statistics */ +void update_task_ravg(struct task_struct *p, struct rq *rq, int event, + u64 wallclock, u64 irqtime) +{ + u64 runtime; + + if (!rq->window_start || sched_disable_window_stats || + p->ravg.mark_start == wallclock) + return; + + lockdep_assert_held(&rq->lock); + + update_window_start(rq, wallclock); + + if (!p->ravg.mark_start) { + update_task_cpu_cycles(p, cpu_of(rq), wallclock); + goto done; + } + + update_task_rq_cpu_cycles(p, rq, event, wallclock, irqtime); + runtime = update_task_demand(p, rq, event, wallclock); + if (runtime) + update_task_burst(p, rq, event, runtime); + update_cpu_busy_time(p, rq, event, wallclock, irqtime); + update_task_pred_demand(rq, p, event); + + if (exiting_task(p)) + goto done; + + trace_sched_update_task_ravg(p, rq, event, wallclock, irqtime, + rq->cc.cycles, rq->cc.time, + p->grp ? &rq->grp_time : NULL); + +done: + p->ravg.mark_start = wallclock; +} + +void sched_account_irqtime(int cpu, struct task_struct *curr, + u64 delta, u64 wallclock) +{ + struct rq *rq = cpu_rq(cpu); + unsigned long flags, nr_windows; + u64 cur_jiffies_ts; + + raw_spin_lock_irqsave(&rq->lock, flags); + + /* + * cputime (wallclock) uses sched_clock so use the same here for + * consistency. + */ + delta += sched_clock() - wallclock; + cur_jiffies_ts = get_jiffies_64(); + + if (is_idle_task(curr)) + update_task_ravg(curr, rq, IRQ_UPDATE, sched_ktime_clock(), + delta); + + nr_windows = cur_jiffies_ts - rq->irqload_ts; + + if (nr_windows) { + if (nr_windows < 10) { + /* Decay CPU's irqload by 3/4 for each window. */ + rq->avg_irqload *= (3 * nr_windows); + rq->avg_irqload = div64_u64(rq->avg_irqload, + 4 * nr_windows); + } else { + rq->avg_irqload = 0; + } + rq->avg_irqload += rq->cur_irqload; + rq->cur_irqload = 0; + } + + rq->cur_irqload += delta; + rq->irqload_ts = cur_jiffies_ts; + raw_spin_unlock_irqrestore(&rq->lock, flags); +} + +void sched_account_irqstart(int cpu, struct task_struct *curr, u64 wallclock) +{ + struct rq *rq = cpu_rq(cpu); + + if (!rq->window_start || sched_disable_window_stats) + return; + + if (is_idle_task(curr)) { + /* We're here without rq->lock held, IRQ disabled */ + raw_spin_lock(&rq->lock); + update_task_cpu_cycles(curr, cpu, sched_ktime_clock()); + raw_spin_unlock(&rq->lock); + } +} + +void reset_task_stats(struct task_struct *p) +{ + u32 sum = 0; + u32 *curr_window_ptr = NULL; + u32 *prev_window_ptr = NULL; + + if (exiting_task(p)) { + sum = EXITING_TASK_MARKER; + } else { + curr_window_ptr = p->ravg.curr_window_cpu; + prev_window_ptr = p->ravg.prev_window_cpu; + memset(curr_window_ptr, 0, sizeof(u32) * nr_cpu_ids); + memset(prev_window_ptr, 0, sizeof(u32) * nr_cpu_ids); + } + + memset(&p->ravg, 0, sizeof(struct ravg)); + + p->ravg.curr_window_cpu = curr_window_ptr; + p->ravg.prev_window_cpu = prev_window_ptr; + + p->ravg.avg_burst = 2 * (u64)sysctl_sched_short_burst; + + /* Retain EXITING_TASK marker */ + p->ravg.sum_history[0] = sum; +} + +void mark_task_starting(struct task_struct *p) +{ + u64 wallclock; + struct rq *rq = task_rq(p); + + if (!rq->window_start || sched_disable_window_stats) { + reset_task_stats(p); + return; + } + + wallclock = sched_ktime_clock(); + p->ravg.mark_start = p->last_wake_ts = wallclock; + p->last_cpu_selected_ts = wallclock; + p->last_switch_out_ts = 0; + update_task_cpu_cycles(p, cpu_of(rq), wallclock); +} + +void set_window_start(struct rq *rq) +{ + static int sync_cpu_available; + + if (rq->window_start) + return; + + if (!sync_cpu_available) { + rq->window_start = sched_ktime_clock(); + sync_cpu_available = 1; + } else { + struct rq *sync_rq = cpu_rq(cpumask_any(cpu_online_mask)); + + raw_spin_unlock(&rq->lock); + double_rq_lock(rq, sync_rq); + rq->window_start = sync_rq->window_start; + rq->curr_runnable_sum = rq->prev_runnable_sum = 0; + rq->nt_curr_runnable_sum = rq->nt_prev_runnable_sum = 0; + raw_spin_unlock(&sync_rq->lock); + } + + rq->curr->ravg.mark_start = rq->window_start; +} + +static void reset_all_task_stats(void) +{ + struct task_struct *g, *p; + + do_each_thread(g, p) { + reset_task_stats(p); + } while_each_thread(g, p); +} + +enum reset_reason_code { + WINDOW_CHANGE, + POLICY_CHANGE, + HIST_SIZE_CHANGE, + FREQ_AGGREGATE_CHANGE, +}; + +const char *sched_window_reset_reasons[] = { + "WINDOW_CHANGE", + "POLICY_CHANGE", + "HIST_SIZE_CHANGE", + "FREQ_AGGREGATE_CHANGE", +}; + +/* Called with IRQs enabled */ +void reset_all_window_stats(u64 window_start, unsigned int window_size) +{ + int cpu, i; + unsigned long flags; + u64 start_ts = sched_ktime_clock(); + int reason = WINDOW_CHANGE; + unsigned int old = 0, new = 0; + + local_irq_save(flags); + + read_lock(&tasklist_lock); + + read_lock(&related_thread_group_lock); + + /* Taking all runqueue locks prevents race with sched_exit(). */ + for_each_possible_cpu(cpu) + raw_spin_lock(&cpu_rq(cpu)->lock); + + sched_disable_window_stats = 1; + + reset_all_task_stats(); + + read_unlock(&tasklist_lock); + + if (window_size) { + sched_ravg_window = window_size * TICK_NSEC; + set_hmp_defaults(); + sched_load_granule = sched_ravg_window / NUM_LOAD_INDICES; + } + + sched_disable_window_stats = 0; + + for_each_possible_cpu(cpu) { + struct rq *rq = cpu_rq(cpu); + + if (window_start) + rq->window_start = window_start; + rq->curr_runnable_sum = rq->prev_runnable_sum = 0; + rq->nt_curr_runnable_sum = rq->nt_prev_runnable_sum = 0; + memset(&rq->grp_time, 0, sizeof(struct group_cpu_time)); + for (i = 0; i < NUM_TRACKED_WINDOWS; i++) { + memset(&rq->load_subs[i], 0, + sizeof(struct load_subtractions)); + clear_top_tasks_table(rq->top_tasks[i]); + clear_top_tasks_bitmap(rq->top_tasks_bitmap[i]); + } + + rq->curr_table = 0; + rq->curr_top = 0; + rq->prev_top = 0; + reset_cpu_hmp_stats(cpu, 1); + } + + if (sched_window_stats_policy != sysctl_sched_window_stats_policy) { + reason = POLICY_CHANGE; + old = sched_window_stats_policy; + new = sysctl_sched_window_stats_policy; + sched_window_stats_policy = sysctl_sched_window_stats_policy; + } else if (sched_ravg_hist_size != sysctl_sched_ravg_hist_size) { + reason = HIST_SIZE_CHANGE; + old = sched_ravg_hist_size; + new = sysctl_sched_ravg_hist_size; + sched_ravg_hist_size = sysctl_sched_ravg_hist_size; + } else if (sched_freq_aggregate != + sysctl_sched_freq_aggregate) { + reason = FREQ_AGGREGATE_CHANGE; + old = sched_freq_aggregate; + new = sysctl_sched_freq_aggregate; + sched_freq_aggregate = sysctl_sched_freq_aggregate; + } + + for_each_possible_cpu(cpu) + raw_spin_unlock(&cpu_rq(cpu)->lock); + + read_unlock(&related_thread_group_lock); + + local_irq_restore(flags); + + trace_sched_reset_all_window_stats(window_start, window_size, + sched_ktime_clock() - start_ts, reason, old, new); +} + +/* + * In this function we match the accumulated subtractions with the current + * and previous windows we are operating with. Ignore any entries where + * the window start in the load_subtraction struct does not match either + * the curent or the previous window. This could happen whenever CPUs + * become idle or busy with interrupts disabled for an extended period. + */ +static inline void account_load_subtractions(struct rq *rq) +{ + u64 ws = rq->window_start; + u64 prev_ws = ws - sched_ravg_window; + struct load_subtractions *ls = rq->load_subs; + int i; + + for (i = 0; i < NUM_TRACKED_WINDOWS; i++) { + if (ls[i].window_start == ws) { + rq->curr_runnable_sum -= ls[i].subs; + rq->nt_curr_runnable_sum -= ls[i].new_subs; + } else if (ls[i].window_start == prev_ws) { + rq->prev_runnable_sum -= ls[i].subs; + rq->nt_prev_runnable_sum -= ls[i].new_subs; + } + + ls[i].subs = 0; + ls[i].new_subs = 0; + } + + BUG_ON((s64)rq->prev_runnable_sum < 0); + BUG_ON((s64)rq->curr_runnable_sum < 0); + BUG_ON((s64)rq->nt_prev_runnable_sum < 0); + BUG_ON((s64)rq->nt_curr_runnable_sum < 0); +} + +static inline u64 freq_policy_load(struct rq *rq, u64 load) +{ + unsigned int reporting_policy = sysctl_sched_freq_reporting_policy; + + switch (reporting_policy) { + case FREQ_REPORT_MAX_CPU_LOAD_TOP_TASK: + load = max_t(u64, load, top_task_load(rq)); + break; + case FREQ_REPORT_TOP_TASK: + load = top_task_load(rq); + break; + case FREQ_REPORT_CPU_LOAD: + break; + default: + break; + } + + return load; +} + +void sched_get_cpus_busy(struct sched_load *busy, + const struct cpumask *query_cpus) +{ + unsigned long flags; + struct rq *rq; + const int cpus = cpumask_weight(query_cpus); + u64 load[cpus], group_load[cpus]; + u64 nload[cpus], ngload[cpus]; + u64 pload[cpus]; + unsigned int max_freq[cpus]; + int notifier_sent = 0; + int early_detection[cpus]; + int cpu, i = 0; + unsigned int window_size; + u64 max_prev_sum = 0; + int max_busy_cpu = cpumask_first(query_cpus); + u64 total_group_load = 0, total_ngload = 0; + bool aggregate_load = false; + struct sched_cluster *cluster = cpu_cluster(cpumask_first(query_cpus)); + + if (unlikely(cpus == 0)) + return; + + local_irq_save(flags); + + /* + * This function could be called in timer context, and the + * current task may have been executing for a long time. Ensure + * that the window stats are current by doing an update. + */ + + for_each_cpu(cpu, query_cpus) + raw_spin_lock(&cpu_rq(cpu)->lock); + + window_size = sched_ravg_window; + + /* + * We don't really need the cluster lock for this entire for loop + * block. However, there is no advantage in optimizing this as rq + * locks are held regardless and would prevent migration anyways + */ + raw_spin_lock(&cluster->load_lock); + + for_each_cpu(cpu, query_cpus) { + rq = cpu_rq(cpu); + + update_task_ravg(rq->curr, rq, TASK_UPDATE, sched_ktime_clock(), + 0); + + /* + * Ensure that we don't report load for 'cpu' again via the + * cpufreq_update_util path in the window that started at + * rq->window_start + */ + rq->load_reported_window = rq->window_start; + + account_load_subtractions(rq); + load[i] = rq->prev_runnable_sum; + nload[i] = rq->nt_prev_runnable_sum; + pload[i] = rq->hmp_stats.pred_demands_sum; + rq->old_estimated_time = pload[i]; + + if (load[i] > max_prev_sum) { + max_prev_sum = load[i]; + max_busy_cpu = cpu; + } + + /* + * sched_get_cpus_busy() is called for all CPUs in a + * frequency domain. So the notifier_sent flag per + * cluster works even when a frequency domain spans + * more than 1 cluster. + */ + if (rq->cluster->notifier_sent) { + notifier_sent = 1; + rq->cluster->notifier_sent = 0; + } + early_detection[i] = (rq->ed_task != NULL); + max_freq[i] = cpu_max_freq(cpu); + i++; + } + + raw_spin_unlock(&cluster->load_lock); + + group_load_in_freq_domain( + &cpu_rq(max_busy_cpu)->freq_domain_cpumask, + &total_group_load, &total_ngload); + aggregate_load = !!(total_group_load > sched_freq_aggregate_threshold); + + i = 0; + for_each_cpu(cpu, query_cpus) { + group_load[i] = 0; + ngload[i] = 0; + + if (early_detection[i]) + goto skip_early; + + rq = cpu_rq(cpu); + if (aggregate_load) { + if (cpu == max_busy_cpu) { + group_load[i] = total_group_load; + ngload[i] = total_ngload; + } + } else { + group_load[i] = rq->grp_time.prev_runnable_sum; + ngload[i] = rq->grp_time.nt_prev_runnable_sum; + } + + load[i] += group_load[i]; + nload[i] += ngload[i]; + + load[i] = freq_policy_load(rq, load[i]); + rq->old_busy_time = load[i]; + + /* + * Scale load in reference to cluster max_possible_freq. + * + * Note that scale_load_to_cpu() scales load in reference to + * the cluster max_freq. + */ + load[i] = scale_load_to_cpu(load[i], cpu); + nload[i] = scale_load_to_cpu(nload[i], cpu); + pload[i] = scale_load_to_cpu(pload[i], cpu); +skip_early: + i++; + } + + for_each_cpu(cpu, query_cpus) + raw_spin_unlock(&(cpu_rq(cpu))->lock); + + local_irq_restore(flags); + + i = 0; + for_each_cpu(cpu, query_cpus) { + rq = cpu_rq(cpu); + + if (early_detection[i]) { + busy[i].prev_load = div64_u64(sched_ravg_window, + NSEC_PER_USEC); + busy[i].new_task_load = 0; + busy[i].predicted_load = 0; + goto exit_early; + } + + load[i] = scale_load_to_freq(load[i], max_freq[i], + cpu_max_possible_freq(cpu)); + nload[i] = scale_load_to_freq(nload[i], max_freq[i], + cpu_max_possible_freq(cpu)); + + pload[i] = scale_load_to_freq(pload[i], max_freq[i], + rq->cluster->max_possible_freq); + + busy[i].prev_load = div64_u64(load[i], NSEC_PER_USEC); + busy[i].new_task_load = div64_u64(nload[i], NSEC_PER_USEC); + busy[i].predicted_load = div64_u64(pload[i], NSEC_PER_USEC); + +exit_early: + trace_sched_get_busy(cpu, busy[i].prev_load, + busy[i].new_task_load, + busy[i].predicted_load, + early_detection[i], + aggregate_load && + cpu == max_busy_cpu); + i++; + } +} + +void sched_set_io_is_busy(int val) +{ + sched_io_is_busy = val; +} + +int sched_set_window(u64 window_start, unsigned int window_size) +{ + u64 now, cur_jiffies, jiffy_ktime_ns; + s64 ws; + unsigned long flags; + + if (window_size * TICK_NSEC < MIN_SCHED_RAVG_WINDOW) + return -EINVAL; + + mutex_lock(&policy_mutex); + + /* + * Get a consistent view of ktime, jiffies, and the time + * since the last jiffy (based on last_jiffies_update). + */ + local_irq_save(flags); + cur_jiffies = jiffy_to_ktime_ns(&now, &jiffy_ktime_ns); + local_irq_restore(flags); + + /* translate window_start from jiffies to nanoseconds */ + ws = (window_start - cur_jiffies); /* jiffy difference */ + ws *= TICK_NSEC; + ws += jiffy_ktime_ns; + + /* + * Roll back calculated window start so that it is in + * the past (window stats must have a current window). + */ + while (ws > now) + ws -= (window_size * TICK_NSEC); + + BUG_ON(sched_ktime_clock() < ws); + + reset_all_window_stats(ws, window_size); + + sched_update_freq_max_load(cpu_possible_mask); + + mutex_unlock(&policy_mutex); + + return 0; +} + +static inline void create_subtraction_entry(struct rq *rq, u64 ws, int index) +{ + rq->load_subs[index].window_start = ws; + rq->load_subs[index].subs = 0; + rq->load_subs[index].new_subs = 0; +} + +static bool get_subtraction_index(struct rq *rq, u64 ws) +{ + int i; + u64 oldest = ULLONG_MAX; + int oldest_index = 0; + + for (i = 0; i < NUM_TRACKED_WINDOWS; i++) { + u64 entry_ws = rq->load_subs[i].window_start; + + if (ws == entry_ws) + return i; + + if (entry_ws < oldest) { + oldest = entry_ws; + oldest_index = i; + } + } + + create_subtraction_entry(rq, ws, oldest_index); + return oldest_index; +} + +static void update_rq_load_subtractions(int index, struct rq *rq, + u32 sub_load, bool new_task) +{ + rq->load_subs[index].subs += sub_load; + if (new_task) + rq->load_subs[index].new_subs += sub_load; +} + +static void update_cluster_load_subtractions(struct task_struct *p, + int cpu, u64 ws, bool new_task) +{ + struct sched_cluster *cluster = cpu_cluster(cpu); + struct cpumask cluster_cpus = cluster->cpus; + u64 prev_ws = ws - sched_ravg_window; + int i; + + cpumask_clear_cpu(cpu, &cluster_cpus); + raw_spin_lock(&cluster->load_lock); + + for_each_cpu(i, &cluster_cpus) { + struct rq *rq = cpu_rq(i); + int index; + + if (p->ravg.curr_window_cpu[i]) { + index = get_subtraction_index(rq, ws); + update_rq_load_subtractions(index, rq, + p->ravg.curr_window_cpu[i], new_task); + p->ravg.curr_window_cpu[i] = 0; + } + + if (p->ravg.prev_window_cpu[i]) { + index = get_subtraction_index(rq, prev_ws); + update_rq_load_subtractions(index, rq, + p->ravg.prev_window_cpu[i], new_task); + p->ravg.prev_window_cpu[i] = 0; + } + } + + raw_spin_unlock(&cluster->load_lock); +} + +static inline void inter_cluster_migration_fixup + (struct task_struct *p, int new_cpu, int task_cpu, bool new_task) +{ + struct rq *dest_rq = cpu_rq(new_cpu); + struct rq *src_rq = cpu_rq(task_cpu); + + if (same_freq_domain(new_cpu, task_cpu)) + return; + + p->ravg.curr_window_cpu[new_cpu] = p->ravg.curr_window; + p->ravg.prev_window_cpu[new_cpu] = p->ravg.prev_window; + + dest_rq->curr_runnable_sum += p->ravg.curr_window; + dest_rq->prev_runnable_sum += p->ravg.prev_window; + + src_rq->curr_runnable_sum -= p->ravg.curr_window_cpu[task_cpu]; + src_rq->prev_runnable_sum -= p->ravg.prev_window_cpu[task_cpu]; + + if (new_task) { + dest_rq->nt_curr_runnable_sum += p->ravg.curr_window; + dest_rq->nt_prev_runnable_sum += p->ravg.prev_window; + + src_rq->nt_curr_runnable_sum -= + p->ravg.curr_window_cpu[task_cpu]; + src_rq->nt_prev_runnable_sum -= + p->ravg.prev_window_cpu[task_cpu]; + } + + p->ravg.curr_window_cpu[task_cpu] = 0; + p->ravg.prev_window_cpu[task_cpu] = 0; + + update_cluster_load_subtractions(p, task_cpu, + src_rq->window_start, new_task); + + BUG_ON((s64)src_rq->prev_runnable_sum < 0); + BUG_ON((s64)src_rq->curr_runnable_sum < 0); + BUG_ON((s64)src_rq->nt_prev_runnable_sum < 0); + BUG_ON((s64)src_rq->nt_curr_runnable_sum < 0); +} + +static int get_top_index(unsigned long *bitmap, unsigned long old_top) +{ + int index = find_next_bit(bitmap, NUM_LOAD_INDICES, old_top); + + if (index == NUM_LOAD_INDICES) + return 0; + + return NUM_LOAD_INDICES - 1 - index; +} + +static void +migrate_top_tasks(struct task_struct *p, struct rq *src_rq, struct rq *dst_rq) +{ + int index; + int top_index; + u32 curr_window = p->ravg.curr_window; + u32 prev_window = p->ravg.prev_window; + u8 src = src_rq->curr_table; + u8 dst = dst_rq->curr_table; + u8 *src_table; + u8 *dst_table; + + if (curr_window) { + src_table = src_rq->top_tasks[src]; + dst_table = dst_rq->top_tasks[dst]; + index = load_to_index(curr_window); + src_table[index] -= 1; + dst_table[index] += 1; + + if (!src_table[index]) + __clear_bit(NUM_LOAD_INDICES - index - 1, + src_rq->top_tasks_bitmap[src]); + + if (dst_table[index] == 1) + __set_bit(NUM_LOAD_INDICES - index - 1, + dst_rq->top_tasks_bitmap[dst]); + + if (index > dst_rq->curr_top) + dst_rq->curr_top = index; + + top_index = src_rq->curr_top; + if (index == top_index && !src_table[index]) + src_rq->curr_top = get_top_index( + src_rq->top_tasks_bitmap[src], top_index); + } + + if (prev_window) { + src = 1 - src; + dst = 1 - dst; + src_table = src_rq->top_tasks[src]; + dst_table = dst_rq->top_tasks[dst]; + index = load_to_index(prev_window); + src_table[index] -= 1; + dst_table[index] += 1; + + if (!src_table[index]) + __clear_bit(NUM_LOAD_INDICES - index - 1, + src_rq->top_tasks_bitmap[src]); + + if (dst_table[index] == 1) + __set_bit(NUM_LOAD_INDICES - index - 1, + dst_rq->top_tasks_bitmap[dst]); + + if (index > dst_rq->prev_top) + dst_rq->prev_top = index; + + top_index = src_rq->prev_top; + if (index == top_index && !src_table[index]) + src_rq->prev_top = get_top_index( + src_rq->top_tasks_bitmap[src], top_index); + } +} + +void fixup_busy_time(struct task_struct *p, int new_cpu) +{ + struct rq *src_rq = task_rq(p); + struct rq *dest_rq = cpu_rq(new_cpu); + u64 wallclock; + u64 *src_curr_runnable_sum, *dst_curr_runnable_sum; + u64 *src_prev_runnable_sum, *dst_prev_runnable_sum; + u64 *src_nt_curr_runnable_sum, *dst_nt_curr_runnable_sum; + u64 *src_nt_prev_runnable_sum, *dst_nt_prev_runnable_sum; + bool new_task; + struct related_thread_group *grp; + + if (!p->on_rq && p->state != TASK_WAKING) + return; + + if (exiting_task(p)) { + clear_ed_task(p, src_rq); + return; + } + + if (p->state == TASK_WAKING) + double_rq_lock(src_rq, dest_rq); + + if (sched_disable_window_stats) + goto done; + + wallclock = sched_ktime_clock(); + + update_task_ravg(task_rq(p)->curr, task_rq(p), + TASK_UPDATE, + wallclock, 0); + update_task_ravg(dest_rq->curr, dest_rq, + TASK_UPDATE, wallclock, 0); + + update_task_ravg(p, task_rq(p), TASK_MIGRATE, + wallclock, 0); + + update_task_cpu_cycles(p, new_cpu, wallclock); + + new_task = is_new_task(p); + /* Protected by rq_lock */ + grp = p->grp; + + /* + * For frequency aggregation, we continue to do migration fixups + * even for intra cluster migrations. This is because, the aggregated + * load has to reported on a single CPU regardless. + */ + if (grp && sched_freq_aggregate) { + struct group_cpu_time *cpu_time; + + cpu_time = &src_rq->grp_time; + src_curr_runnable_sum = &cpu_time->curr_runnable_sum; + src_prev_runnable_sum = &cpu_time->prev_runnable_sum; + src_nt_curr_runnable_sum = &cpu_time->nt_curr_runnable_sum; + src_nt_prev_runnable_sum = &cpu_time->nt_prev_runnable_sum; + + cpu_time = &dest_rq->grp_time; + dst_curr_runnable_sum = &cpu_time->curr_runnable_sum; + dst_prev_runnable_sum = &cpu_time->prev_runnable_sum; + dst_nt_curr_runnable_sum = &cpu_time->nt_curr_runnable_sum; + dst_nt_prev_runnable_sum = &cpu_time->nt_prev_runnable_sum; + + if (p->ravg.curr_window) { + *src_curr_runnable_sum -= p->ravg.curr_window; + *dst_curr_runnable_sum += p->ravg.curr_window; + if (new_task) { + *src_nt_curr_runnable_sum -= + p->ravg.curr_window; + *dst_nt_curr_runnable_sum += + p->ravg.curr_window; + } + } + + if (p->ravg.prev_window) { + *src_prev_runnable_sum -= p->ravg.prev_window; + *dst_prev_runnable_sum += p->ravg.prev_window; + if (new_task) { + *src_nt_prev_runnable_sum -= + p->ravg.prev_window; + *dst_nt_prev_runnable_sum += + p->ravg.prev_window; + } + } + } else { + inter_cluster_migration_fixup(p, new_cpu, + task_cpu(p), new_task); + } + + migrate_top_tasks(p, src_rq, dest_rq); + + if (!same_freq_domain(new_cpu, task_cpu(p))) { + cpufreq_update_util(dest_rq, SCHED_CPUFREQ_INTERCLUSTER_MIG); + cpufreq_update_util(src_rq, SCHED_CPUFREQ_INTERCLUSTER_MIG); + } + + if (p == src_rq->ed_task) { + src_rq->ed_task = NULL; + if (!dest_rq->ed_task) + dest_rq->ed_task = p; + } + +done: + if (p->state == TASK_WAKING) + double_rq_unlock(src_rq, dest_rq); +} + +#define sched_up_down_migrate_auto_update 1 +static void check_for_up_down_migrate_update(const struct cpumask *cpus) +{ + int i = cpumask_first(cpus); + + if (!sched_up_down_migrate_auto_update) + return; + + if (cpu_max_possible_capacity(i) == max_possible_capacity) + return; + + if (cpu_max_possible_freq(i) == cpu_max_freq(i)) + up_down_migrate_scale_factor = 1024; + else + up_down_migrate_scale_factor = (1024 * + cpu_max_possible_freq(i)) / cpu_max_freq(i); + + update_up_down_migrate(); +} + +/* Return cluster which can offer required capacity for group */ +static struct sched_cluster *best_cluster(struct related_thread_group *grp, + u64 total_demand, bool group_boost) +{ + struct sched_cluster *cluster = NULL; + + for_each_sched_cluster(cluster) { + if (group_will_fit(cluster, grp, total_demand, group_boost)) + return cluster; + } + + return sched_cluster[0]; +} + +static void _set_preferred_cluster(struct related_thread_group *grp) +{ + struct task_struct *p; + u64 combined_demand = 0; + bool boost_on_big = sched_boost_policy() == SCHED_BOOST_ON_BIG; + bool group_boost = false; + u64 wallclock; + + if (list_empty(&grp->tasks)) + return; + + wallclock = sched_ktime_clock(); + + /* + * wakeup of two or more related tasks could race with each other and + * could result in multiple calls to _set_preferred_cluster being issued + * at same time. Avoid overhead in such cases of rechecking preferred + * cluster + */ + if (wallclock - grp->last_update < sched_ravg_window / 10) + return; + + list_for_each_entry(p, &grp->tasks, grp_list) { + if (boost_on_big && task_sched_boost(p)) { + group_boost = true; + break; + } + + if (p->ravg.mark_start < wallclock - + (sched_ravg_window * sched_ravg_hist_size)) + continue; + + combined_demand += p->ravg.demand; + + } + + grp->preferred_cluster = best_cluster(grp, + combined_demand, group_boost); + grp->last_update = sched_ktime_clock(); + trace_sched_set_preferred_cluster(grp, combined_demand); +} + +void set_preferred_cluster(struct related_thread_group *grp) +{ + raw_spin_lock(&grp->lock); + _set_preferred_cluster(grp); + raw_spin_unlock(&grp->lock); +} + +#define ADD_TASK 0 +#define REM_TASK 1 + +#define DEFAULT_CGROUP_COLOC_ID 1 + +/* + * Task's cpu usage is accounted in: + * rq->curr/prev_runnable_sum, when its ->grp is NULL + * grp->cpu_time[cpu]->curr/prev_runnable_sum, when its ->grp is !NULL + * + * Transfer task's cpu usage between those counters when transitioning between + * groups + */ +static void transfer_busy_time(struct rq *rq, struct related_thread_group *grp, + struct task_struct *p, int event) +{ + u64 wallclock; + struct group_cpu_time *cpu_time; + u64 *src_curr_runnable_sum, *dst_curr_runnable_sum; + u64 *src_prev_runnable_sum, *dst_prev_runnable_sum; + u64 *src_nt_curr_runnable_sum, *dst_nt_curr_runnable_sum; + u64 *src_nt_prev_runnable_sum, *dst_nt_prev_runnable_sum; + int migrate_type; + int cpu = cpu_of(rq); + bool new_task; + int i; + + if (!sched_freq_aggregate) + return; + + wallclock = sched_ktime_clock(); + + update_task_ravg(rq->curr, rq, TASK_UPDATE, wallclock, 0); + update_task_ravg(p, rq, TASK_UPDATE, wallclock, 0); + new_task = is_new_task(p); + + cpu_time = &rq->grp_time; + if (event == ADD_TASK) { + migrate_type = RQ_TO_GROUP; + + src_curr_runnable_sum = &rq->curr_runnable_sum; + dst_curr_runnable_sum = &cpu_time->curr_runnable_sum; + src_prev_runnable_sum = &rq->prev_runnable_sum; + dst_prev_runnable_sum = &cpu_time->prev_runnable_sum; + + src_nt_curr_runnable_sum = &rq->nt_curr_runnable_sum; + dst_nt_curr_runnable_sum = &cpu_time->nt_curr_runnable_sum; + src_nt_prev_runnable_sum = &rq->nt_prev_runnable_sum; + dst_nt_prev_runnable_sum = &cpu_time->nt_prev_runnable_sum; + + *src_curr_runnable_sum -= p->ravg.curr_window_cpu[cpu]; + *src_prev_runnable_sum -= p->ravg.prev_window_cpu[cpu]; + if (new_task) { + *src_nt_curr_runnable_sum -= + p->ravg.curr_window_cpu[cpu]; + *src_nt_prev_runnable_sum -= + p->ravg.prev_window_cpu[cpu]; + } + + update_cluster_load_subtractions(p, cpu, + rq->window_start, new_task); + + } else { + migrate_type = GROUP_TO_RQ; + + src_curr_runnable_sum = &cpu_time->curr_runnable_sum; + dst_curr_runnable_sum = &rq->curr_runnable_sum; + src_prev_runnable_sum = &cpu_time->prev_runnable_sum; + dst_prev_runnable_sum = &rq->prev_runnable_sum; + + src_nt_curr_runnable_sum = &cpu_time->nt_curr_runnable_sum; + dst_nt_curr_runnable_sum = &rq->nt_curr_runnable_sum; + src_nt_prev_runnable_sum = &cpu_time->nt_prev_runnable_sum; + dst_nt_prev_runnable_sum = &rq->nt_prev_runnable_sum; + + *src_curr_runnable_sum -= p->ravg.curr_window; + *src_prev_runnable_sum -= p->ravg.prev_window; + if (new_task) { + *src_nt_curr_runnable_sum -= p->ravg.curr_window; + *src_nt_prev_runnable_sum -= p->ravg.prev_window; + } + + /* + * Need to reset curr/prev windows for all CPUs, not just the + * ones in the same cluster. Since inter cluster migrations + * did not result in the appropriate book keeping, the values + * per CPU would be inaccurate. + */ + for_each_possible_cpu(i) { + p->ravg.curr_window_cpu[i] = 0; + p->ravg.prev_window_cpu[i] = 0; + } + } + + *dst_curr_runnable_sum += p->ravg.curr_window; + *dst_prev_runnable_sum += p->ravg.prev_window; + if (new_task) { + *dst_nt_curr_runnable_sum += p->ravg.curr_window; + *dst_nt_prev_runnable_sum += p->ravg.prev_window; + } + + /* + * When a task enter or exits a group, it's curr and prev windows are + * moved to a single CPU. This behavior might be sub-optimal in the + * exit case, however, it saves us the overhead of handling inter + * cluster migration fixups while the task is part of a related group. + */ + p->ravg.curr_window_cpu[cpu] = p->ravg.curr_window; + p->ravg.prev_window_cpu[cpu] = p->ravg.prev_window; + + trace_sched_migration_update_sum(p, migrate_type, rq); + + BUG_ON((s64)*src_curr_runnable_sum < 0); + BUG_ON((s64)*src_prev_runnable_sum < 0); + BUG_ON((s64)*src_nt_curr_runnable_sum < 0); + BUG_ON((s64)*src_nt_prev_runnable_sum < 0); +} + +static inline struct related_thread_group* +lookup_related_thread_group(unsigned int group_id) +{ + return related_thread_groups[group_id]; +} + +int alloc_related_thread_groups(void) +{ + int i, ret; + struct related_thread_group *grp; + + /* groupd_id = 0 is invalid as it's special id to remove group. */ + for (i = 1; i < MAX_NUM_CGROUP_COLOC_ID; i++) { + grp = kzalloc(sizeof(*grp), GFP_NOWAIT); + if (!grp) { + ret = -ENOMEM; + goto err; + } + + grp->id = i; + INIT_LIST_HEAD(&grp->tasks); + INIT_LIST_HEAD(&grp->list); + raw_spin_lock_init(&grp->lock); + + related_thread_groups[i] = grp; + } + + return 0; + +err: + for (i = 1; i < MAX_NUM_CGROUP_COLOC_ID; i++) { + grp = lookup_related_thread_group(i); + if (grp) { + kfree(grp); + related_thread_groups[i] = NULL; + } else { + break; + } + } + + return ret; +} + +static void remove_task_from_group(struct task_struct *p) +{ + struct related_thread_group *grp = p->grp; + struct rq *rq; + int empty_group = 1; + + raw_spin_lock(&grp->lock); + + rq = __task_rq_lock(p); + transfer_busy_time(rq, p->grp, p, REM_TASK); + list_del_init(&p->grp_list); + rcu_assign_pointer(p->grp, NULL); + __task_rq_unlock(rq); + + if (!list_empty(&grp->tasks)) { + empty_group = 0; + _set_preferred_cluster(grp); + } + + raw_spin_unlock(&grp->lock); + + /* Reserved groups cannot be destroyed */ + if (empty_group && grp->id != DEFAULT_CGROUP_COLOC_ID) + /* + * We test whether grp->list is attached with list_empty() + * hence re-init the list after deletion. + */ + list_del_init(&grp->list); +} + +static int +add_task_to_group(struct task_struct *p, struct related_thread_group *grp) +{ + struct rq *rq; + + raw_spin_lock(&grp->lock); + + /* + * Change p->grp under rq->lock. Will prevent races with read-side + * reference of p->grp in various hot-paths + */ + rq = __task_rq_lock(p); + transfer_busy_time(rq, grp, p, ADD_TASK); + list_add(&p->grp_list, &grp->tasks); + rcu_assign_pointer(p->grp, grp); + __task_rq_unlock(rq); + + _set_preferred_cluster(grp); + + raw_spin_unlock(&grp->lock); + + return 0; +} + +void add_new_task_to_grp(struct task_struct *new) +{ + unsigned long flags; + struct related_thread_group *grp; + struct task_struct *leader = new->group_leader; + unsigned int leader_grp_id = sched_get_group_id(leader); + + if (!sysctl_sched_enable_thread_grouping && + leader_grp_id != DEFAULT_CGROUP_COLOC_ID) + return; + + if (thread_group_leader(new)) + return; + + if (leader_grp_id == DEFAULT_CGROUP_COLOC_ID) { + if (!same_schedtune(new, leader)) + return; + } + + write_lock_irqsave(&related_thread_group_lock, flags); + + rcu_read_lock(); + grp = task_related_thread_group(leader); + rcu_read_unlock(); + + /* + * It's possible that someone already added the new task to the + * group. A leader's thread group is updated prior to calling + * this function. It's also possible that the leader has exited + * the group. In either case, there is nothing else to do. + */ + if (!grp || new->grp) { + write_unlock_irqrestore(&related_thread_group_lock, flags); + return; + } + + raw_spin_lock(&grp->lock); + + rcu_assign_pointer(new->grp, grp); + list_add(&new->grp_list, &grp->tasks); + + raw_spin_unlock(&grp->lock); + write_unlock_irqrestore(&related_thread_group_lock, flags); +} + +static int __sched_set_group_id(struct task_struct *p, unsigned int group_id) +{ + int rc = 0; + unsigned long flags; + struct related_thread_group *grp = NULL; + + if (group_id >= MAX_NUM_CGROUP_COLOC_ID) + return -EINVAL; + + raw_spin_lock_irqsave(&p->pi_lock, flags); + write_lock(&related_thread_group_lock); + + /* Switching from one group to another directly is not permitted */ + if ((current != p && p->flags & PF_EXITING) || + (!p->grp && !group_id) || + (p->grp && group_id)) + goto done; + + if (!group_id) { + remove_task_from_group(p); + goto done; + } + + grp = lookup_related_thread_group(group_id); + if (list_empty(&grp->list)) + list_add(&grp->list, &active_related_thread_groups); + + rc = add_task_to_group(p, grp); +done: + write_unlock(&related_thread_group_lock); + raw_spin_unlock_irqrestore(&p->pi_lock, flags); + + return rc; +} + +int sched_set_group_id(struct task_struct *p, unsigned int group_id) +{ + /* DEFAULT_CGROUP_COLOC_ID is a reserved id */ + if (group_id == DEFAULT_CGROUP_COLOC_ID) + return -EINVAL; + + return __sched_set_group_id(p, group_id); +} + +unsigned int sched_get_group_id(struct task_struct *p) +{ + unsigned int group_id; + struct related_thread_group *grp; + + rcu_read_lock(); + grp = task_related_thread_group(p); + group_id = grp ? grp->id : 0; + rcu_read_unlock(); + + return group_id; +} + +#if defined(CONFIG_SCHED_TUNE) && defined(CONFIG_CGROUP_SCHEDTUNE) +/* + * We create a default colocation group at boot. There is no need to + * synchronize tasks between cgroups at creation time because the + * correct cgroup hierarchy is not available at boot. Therefore cgroup + * colocation is turned off by default even though the colocation group + * itself has been allocated. Furthermore this colocation group cannot + * be destroyted once it has been created. All of this has been as part + * of runtime optimizations. + * + * The job of synchronizing tasks to the colocation group is done when + * the colocation flag in the cgroup is turned on. + */ +static int __init create_default_coloc_group(void) +{ + struct related_thread_group *grp = NULL; + unsigned long flags; + + grp = lookup_related_thread_group(DEFAULT_CGROUP_COLOC_ID); + write_lock_irqsave(&related_thread_group_lock, flags); + list_add(&grp->list, &active_related_thread_groups); + write_unlock_irqrestore(&related_thread_group_lock, flags); + + update_freq_aggregate_threshold(MAX_FREQ_AGGR_THRESH); + return 0; +} +late_initcall(create_default_coloc_group); + +int sync_cgroup_colocation(struct task_struct *p, bool insert) +{ + unsigned int grp_id = insert ? DEFAULT_CGROUP_COLOC_ID : 0; + + return __sched_set_group_id(p, grp_id); +} +#endif + +static void update_cpu_cluster_capacity(const cpumask_t *cpus) +{ + int i; + struct sched_cluster *cluster; + struct cpumask cpumask; + + cpumask_copy(&cpumask, cpus); + pre_big_task_count_change(cpu_possible_mask); + + for_each_cpu(i, &cpumask) { + cluster = cpu_rq(i)->cluster; + cpumask_andnot(&cpumask, &cpumask, &cluster->cpus); + + cluster->capacity = compute_capacity(cluster); + cluster->load_scale_factor = compute_load_scale_factor(cluster); + + /* 'cpus' can contain cpumask more than one cluster */ + check_for_up_down_migrate_update(&cluster->cpus); + } + + __update_min_max_capacity(); + + post_big_task_count_change(cpu_possible_mask); +} + +static DEFINE_SPINLOCK(cpu_freq_min_max_lock); +void sched_update_cpu_freq_min_max(const cpumask_t *cpus, u32 fmin, u32 fmax) +{ + struct cpumask cpumask; + struct sched_cluster *cluster; + int i, update_capacity = 0; + unsigned long flags; + + spin_lock_irqsave(&cpu_freq_min_max_lock, flags); + cpumask_copy(&cpumask, cpus); + for_each_cpu(i, &cpumask) { + cluster = cpu_rq(i)->cluster; + cpumask_andnot(&cpumask, &cpumask, &cluster->cpus); + + update_capacity += (cluster->max_mitigated_freq != fmax); + cluster->max_mitigated_freq = fmax; + } + spin_unlock_irqrestore(&cpu_freq_min_max_lock, flags); + + if (update_capacity) + update_cpu_cluster_capacity(cpus); +} + +static int cpufreq_notifier_policy(struct notifier_block *nb, + unsigned long val, void *data) +{ + struct cpufreq_policy *policy = (struct cpufreq_policy *)data; + struct sched_cluster *cluster = NULL; + struct cpumask policy_cluster = *policy->related_cpus; + unsigned int orig_max_freq = 0; + int i, j, update_capacity = 0; + + if (val != CPUFREQ_NOTIFY && val != CPUFREQ_REMOVE_POLICY && + val != CPUFREQ_CREATE_POLICY) + return 0; + + if (val == CPUFREQ_REMOVE_POLICY || val == CPUFREQ_CREATE_POLICY) { + update_min_max_capacity(); + return 0; + } + + max_possible_freq = max(max_possible_freq, policy->cpuinfo.max_freq); + if (min_max_freq == 1) + min_max_freq = UINT_MAX; + min_max_freq = min(min_max_freq, policy->cpuinfo.max_freq); + BUG_ON(!min_max_freq); + BUG_ON(!policy->max); + + for_each_cpu(i, &policy_cluster) { + cluster = cpu_rq(i)->cluster; + cpumask_andnot(&policy_cluster, &policy_cluster, + &cluster->cpus); + + orig_max_freq = cluster->max_freq; + cluster->min_freq = policy->min; + cluster->max_freq = policy->max; + cluster->cur_freq = policy->cur; + + if (!cluster->freq_init_done) { + mutex_lock(&cluster_lock); + for_each_cpu(j, &cluster->cpus) + cpumask_copy(&cpu_rq(j)->freq_domain_cpumask, + policy->related_cpus); + cluster->max_possible_freq = policy->cpuinfo.max_freq; + cluster->max_possible_capacity = + compute_max_possible_capacity(cluster); + cluster->freq_init_done = true; + + sort_clusters(); + update_all_clusters_stats(); + mutex_unlock(&cluster_lock); + continue; + } + + update_capacity += (orig_max_freq != cluster->max_freq); + } + + if (update_capacity) + update_cpu_cluster_capacity(policy->related_cpus); + + return 0; +} + +static int cpufreq_notifier_trans(struct notifier_block *nb, + unsigned long val, void *data) +{ + struct cpufreq_freqs *freq = (struct cpufreq_freqs *)data; + unsigned int cpu = freq->cpu, new_freq = freq->new; + unsigned long flags; + struct sched_cluster *cluster; + struct cpumask policy_cpus = cpu_rq(cpu)->freq_domain_cpumask; + int i, j; + + if (val != CPUFREQ_POSTCHANGE) + return 0; + + BUG_ON(!new_freq); + + if (cpu_cur_freq(cpu) == new_freq) + return 0; + + for_each_cpu(i, &policy_cpus) { + cluster = cpu_rq(i)->cluster; + + for_each_cpu(j, &cluster->cpus) { + struct rq *rq = cpu_rq(j); + + raw_spin_lock_irqsave(&rq->lock, flags); + update_task_ravg(rq->curr, rq, TASK_UPDATE, + sched_ktime_clock(), 0); + raw_spin_unlock_irqrestore(&rq->lock, flags); + } + + cluster->cur_freq = new_freq; + cpumask_andnot(&policy_cpus, &policy_cpus, &cluster->cpus); + } + + return 0; +} + +static int pwr_stats_ready_notifier(struct notifier_block *nb, + unsigned long cpu, void *data) +{ + cpumask_t mask = CPU_MASK_NONE; + + cpumask_set_cpu(cpu, &mask); + sched_update_freq_max_load(&mask); + + mutex_lock(&cluster_lock); + sort_clusters(); + mutex_unlock(&cluster_lock); + + return 0; +} + +static struct notifier_block notifier_policy_block = { + .notifier_call = cpufreq_notifier_policy +}; + +static struct notifier_block notifier_trans_block = { + .notifier_call = cpufreq_notifier_trans +}; + +static struct notifier_block notifier_pwr_stats_ready = { + .notifier_call = pwr_stats_ready_notifier +}; + +int __weak register_cpu_pwr_stats_ready_notifier(struct notifier_block *nb) +{ + return -EINVAL; +} + +static int register_sched_callback(void) +{ + int ret; + + ret = cpufreq_register_notifier(¬ifier_policy_block, + CPUFREQ_POLICY_NOTIFIER); + + if (!ret) + ret = cpufreq_register_notifier(¬ifier_trans_block, + CPUFREQ_TRANSITION_NOTIFIER); + + register_cpu_pwr_stats_ready_notifier(¬ifier_pwr_stats_ready); + + return 0; +} + +/* + * cpufreq callbacks can be registered at core_initcall or later time. + * Any registration done prior to that is "forgotten" by cpufreq. See + * initialization of variable init_cpufreq_transition_notifier_list_called + * for further information. + */ +core_initcall(register_sched_callback); + +int update_preferred_cluster(struct related_thread_group *grp, + struct task_struct *p, u32 old_load) +{ + u32 new_load = task_load(p); + + if (!grp) + return 0; + + /* + * Update if task's load has changed significantly or a complete window + * has passed since we last updated preference + */ + if (abs(new_load - old_load) > sched_ravg_window / 4 || + sched_ktime_clock() - grp->last_update > sched_ravg_window) + return 1; + + return 0; +} + +bool early_detection_notify(struct rq *rq, u64 wallclock) +{ + struct task_struct *p; + int loop_max = 10; + + if (sched_boost_policy() == SCHED_BOOST_NONE || !rq->cfs.h_nr_running) + return 0; + + rq->ed_task = NULL; + list_for_each_entry(p, &rq->cfs_tasks, se.group_node) { + if (!loop_max) + break; + + if (wallclock - p->last_wake_ts >= EARLY_DETECTION_DURATION) { + rq->ed_task = p; + return 1; + } + + loop_max--; + } + + return 0; +} + +void update_avg_burst(struct task_struct *p) +{ + update_avg(&p->ravg.avg_burst, p->ravg.curr_burst); + p->ravg.curr_burst = 0; +} + +void note_task_waking(struct task_struct *p, u64 wallclock) +{ + u64 sleep_time = wallclock - p->last_switch_out_ts; + + /* + * When a short burst and short sleeping task goes for a long + * sleep, the task's avg_sleep_time gets boosted. It will not + * come below short_sleep threshold for a lot of time and it + * results in incorrect packing. The idead behind tracking + * avg_sleep_time is to detect if a task is short sleeping + * or not. So limit the sleep time to twice the short sleep + * threshold. For regular long sleeping tasks, the avg_sleep_time + * would be higher than threshold, and packing happens correctly. + */ + sleep_time = min_t(u64, sleep_time, 2 * sysctl_sched_short_sleep); + update_avg(&p->ravg.avg_sleep_time, sleep_time); + + p->last_wake_ts = wallclock; +} + +#ifdef CONFIG_CGROUP_SCHED +u64 cpu_upmigrate_discourage_read_u64(struct cgroup_subsys_state *css, + struct cftype *cft) +{ + struct task_group *tg = css_tg(css); + + return tg->upmigrate_discouraged; +} + +int cpu_upmigrate_discourage_write_u64(struct cgroup_subsys_state *css, + struct cftype *cft, u64 upmigrate_discourage) +{ + struct task_group *tg = css_tg(css); + int discourage = upmigrate_discourage > 0; + + if (tg->upmigrate_discouraged == discourage) + return 0; + + /* + * Revisit big-task classification for tasks of this cgroup. It would + * have been efficient to walk tasks of just this cgroup in running + * state, but we don't have easy means to do that. Walk all tasks in + * running state on all cpus instead and re-visit their big task + * classification. + */ + get_online_cpus(); + pre_big_task_count_change(cpu_online_mask); + + tg->upmigrate_discouraged = discourage; + + post_big_task_count_change(cpu_online_mask); + put_online_cpus(); + + return 0; +} +#endif /* CONFIG_CGROUP_SCHED */ |