/* * kernel/sched/core.c * * Kernel scheduler and related syscalls * * Copyright (C) 1991-2002 Linus Torvalds * * 1996-12-23 Modified by Dave Grothe to fix bugs in semaphores and * make semaphores SMP safe * 1998-11-19 Implemented schedule_timeout() and related stuff * by Andrea Arcangeli * 2002-01-04 New ultra-scalable O(1) scheduler by Ingo Molnar: * hybrid priority-list and round-robin design with * an array-switch method of distributing timeslices * and per-CPU runqueues. Cleanups and useful suggestions * by Davide Libenzi, preemptible kernel bits by Robert Love. * 2003-09-03 Interactivity tuning by Con Kolivas. * 2004-04-02 Scheduler domains code by Nick Piggin * 2007-04-15 Work begun on replacing all interactivity tuning with a * fair scheduling design by Con Kolivas. * 2007-05-05 Load balancing (smp-nice) and other improvements * by Peter Williams * 2007-05-06 Interactivity improvements to CFS by Mike Galbraith * 2007-07-01 Group scheduling enhancements by Srivatsa Vaddagiri * 2007-11-29 RT balancing improvements by Steven Rostedt, Gregory Haskins, * Thomas Gleixner, Mike Kravetz */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef CONFIG_PARAVIRT #include #endif #include "sched.h" #include "../workqueue_sched.h" #define CREATE_TRACE_POINTS #include ATOMIC_NOTIFIER_HEAD(migration_notifier_head); void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period) { unsigned long delta; ktime_t soft, hard, now; for (;;) { if (hrtimer_active(period_timer)) break; now = hrtimer_cb_get_time(period_timer); hrtimer_forward(period_timer, now, period); soft = hrtimer_get_softexpires(period_timer); hard = hrtimer_get_expires(period_timer); delta = ktime_to_ns(ktime_sub(hard, soft)); __hrtimer_start_range_ns(period_timer, soft, delta, HRTIMER_MODE_ABS_PINNED, 0); } } DEFINE_MUTEX(sched_domains_mutex); DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); static void update_rq_clock_task(struct rq *rq, s64 delta); void update_rq_clock(struct rq *rq) { s64 delta; if (rq->skip_clock_update > 0) return; delta = sched_clock_cpu(cpu_of(rq)) - rq->clock; rq->clock += delta; update_rq_clock_task(rq, delta); } #define SCHED_FEAT(name, enabled) \ (1UL << __SCHED_FEAT_##name) * enabled | const_debug unsigned int sysctl_sched_features = #include "features.h" 0; #undef SCHED_FEAT #ifdef CONFIG_SCHED_DEBUG #define SCHED_FEAT(name, enabled) \ #name , static __read_mostly char *sched_feat_names[] = { #include "features.h" NULL }; #undef SCHED_FEAT static int sched_feat_show(struct seq_file *m, void *v) { int i; for (i = 0; i < __SCHED_FEAT_NR; i++) { if (!(sysctl_sched_features & (1UL << i))) seq_puts(m, "NO_"); seq_printf(m, "%s ", sched_feat_names[i]); } seq_puts(m, "\n"); return 0; } #ifdef HAVE_JUMP_LABEL #define jump_label_key__true STATIC_KEY_INIT_TRUE #define jump_label_key__false STATIC_KEY_INIT_FALSE #define SCHED_FEAT(name, enabled) \ jump_label_key__##enabled , struct static_key sched_feat_keys[__SCHED_FEAT_NR] = { #include "features.h" }; #undef SCHED_FEAT static void sched_feat_disable(int i) { if (static_key_enabled(&sched_feat_keys[i])) static_key_slow_dec(&sched_feat_keys[i]); } static void sched_feat_enable(int i) { if (!static_key_enabled(&sched_feat_keys[i])) static_key_slow_inc(&sched_feat_keys[i]); } #else static void sched_feat_disable(int i) { }; static void sched_feat_enable(int i) { }; #endif static ssize_t sched_feat_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { char buf[64]; char *cmp; int neg = 0; int i; if (cnt > 63) cnt = 63; if (copy_from_user(&buf, ubuf, cnt)) return -EFAULT; buf[cnt] = 0; cmp = strstrip(buf); if (strncmp(cmp, "NO_", 3) == 0) { neg = 1; cmp += 3; } for (i = 0; i < __SCHED_FEAT_NR; i++) { if (strcmp(cmp, sched_feat_names[i]) == 0) { if (neg) { sysctl_sched_features &= ~(1UL << i); sched_feat_disable(i); } else { sysctl_sched_features |= (1UL << i); sched_feat_enable(i); } break; } } if (i == __SCHED_FEAT_NR) return -EINVAL; *ppos += cnt; return cnt; } static int sched_feat_open(struct inode *inode, struct file *filp) { return single_open(filp, sched_feat_show, NULL); } static const struct file_operations sched_feat_fops = { .open = sched_feat_open, .write = sched_feat_write, .read = seq_read, .llseek = seq_lseek, .release = single_release, }; static __init int sched_init_debug(void) { debugfs_create_file("sched_features", 0644, NULL, NULL, &sched_feat_fops); return 0; } late_initcall(sched_init_debug); #endif const_debug unsigned int sysctl_sched_nr_migrate = 32; const_debug unsigned int sysctl_sched_time_avg = MSEC_PER_SEC; unsigned int sysctl_sched_rt_period = 1000000; __read_mostly int scheduler_running; int sysctl_sched_rt_runtime = 950000; static inline struct rq *__task_rq_lock(struct task_struct *p) __acquires(rq->lock) { struct rq *rq; lockdep_assert_held(&p->pi_lock); for (;;) { rq = task_rq(p); raw_spin_lock(&rq->lock); if (likely(rq == task_rq(p))) return rq; raw_spin_unlock(&rq->lock); } } static struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags) __acquires(p->pi_lock) __acquires(rq->lock) { struct rq *rq; for (;;) { raw_spin_lock_irqsave(&p->pi_lock, *flags); rq = task_rq(p); raw_spin_lock(&rq->lock); if (likely(rq == task_rq(p))) return rq; raw_spin_unlock(&rq->lock); raw_spin_unlock_irqrestore(&p->pi_lock, *flags); } } static void __task_rq_unlock(struct rq *rq) __releases(rq->lock) { raw_spin_unlock(&rq->lock); } static inline void task_rq_unlock(struct rq *rq, struct task_struct *p, unsigned long *flags) __releases(rq->lock) __releases(p->pi_lock) { raw_spin_unlock(&rq->lock); raw_spin_unlock_irqrestore(&p->pi_lock, *flags); } static struct rq *this_rq_lock(void) __acquires(rq->lock) { struct rq *rq; local_irq_disable(); rq = this_rq(); raw_spin_lock(&rq->lock); return rq; } #ifdef CONFIG_SCHED_HRTICK static void hrtick_clear(struct rq *rq) { if (hrtimer_active(&rq->hrtick_timer)) hrtimer_cancel(&rq->hrtick_timer); } static enum hrtimer_restart hrtick(struct hrtimer *timer) { struct rq *rq = container_of(timer, struct rq, hrtick_timer); WARN_ON_ONCE(cpu_of(rq) != smp_processor_id()); raw_spin_lock(&rq->lock); update_rq_clock(rq); rq->curr->sched_class->task_tick(rq, rq->curr, 1); raw_spin_unlock(&rq->lock); return HRTIMER_NORESTART; } #ifdef CONFIG_SMP static void __hrtick_start(void *arg) { struct rq *rq = arg; struct hrtimer *timer = &rq->hrtick_timer; ktime_t soft, hard; unsigned long delta; soft = hrtimer_get_softexpires(timer); hard = hrtimer_get_expires(timer); delta = ktime_to_ns(ktime_sub(hard, soft)); raw_spin_lock(&rq->lock); __hrtimer_start_range_ns(timer, soft, delta, HRTIMER_MODE_ABS, 0); rq->hrtick_csd_pending = 0; raw_spin_unlock(&rq->lock); } void hrtick_start(struct rq *rq, u64 delay) { struct hrtimer *timer = &rq->hrtick_timer; ktime_t time = ktime_add_ns(timer->base->get_time(), delay); hrtimer_set_expires(timer, time); if (rq == this_rq()) { __hrtimer_start_range_ns(timer, ns_to_ktime(delay), 0, HRTIMER_MODE_REL_PINNED, 0); } else if (!rq->hrtick_csd_pending) { __smp_call_function_single(cpu_of(rq), &rq->hrtick_csd, 0); rq->hrtick_csd_pending = 1; } } static int hotplug_hrtick(struct notifier_block *nfb, unsigned long action, void *hcpu) { int cpu = (int)(long)hcpu; switch (action) { case CPU_UP_CANCELED: case CPU_UP_CANCELED_FROZEN: case CPU_DOWN_PREPARE: case CPU_DOWN_PREPARE_FROZEN: case CPU_DEAD: case CPU_DEAD_FROZEN: hrtick_clear(cpu_rq(cpu)); return NOTIFY_OK; } return NOTIFY_DONE; } static __init void init_hrtick(void) { hotcpu_notifier(hotplug_hrtick, 0); } #else void hrtick_start(struct rq *rq, u64 delay) { __hrtimer_start_range_ns(&rq->hrtick_timer, ns_to_ktime(delay), 0, HRTIMER_MODE_REL_PINNED, 0); } static inline void init_hrtick(void) { } #endif static void init_rq_hrtick(struct rq *rq) { #ifdef CONFIG_SMP rq->hrtick_csd_pending = 0; rq->hrtick_csd.flags = 0; rq->hrtick_csd.func = __hrtick_start; rq->hrtick_csd.info = rq; #endif hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); rq->hrtick_timer.function = hrtick; } #else static inline void hrtick_clear(struct rq *rq) { } static inline void init_rq_hrtick(struct rq *rq) { } static inline void init_hrtick(void) { } #endif #ifdef CONFIG_SMP #ifndef tsk_is_polling #define tsk_is_polling(t) test_tsk_thread_flag(t, TIF_POLLING_NRFLAG) #endif void resched_task(struct task_struct *p) { int cpu; assert_raw_spin_locked(&task_rq(p)->lock); if (test_tsk_need_resched(p)) return; set_tsk_need_resched(p); cpu = task_cpu(p); if (cpu == smp_processor_id()) return; smp_mb(); if (!tsk_is_polling(p)) smp_send_reschedule(cpu); } void resched_cpu(int cpu) { struct rq *rq = cpu_rq(cpu); unsigned long flags; if (!raw_spin_trylock_irqsave(&rq->lock, flags)) return; resched_task(cpu_curr(cpu)); raw_spin_unlock_irqrestore(&rq->lock, flags); } #ifdef CONFIG_NO_HZ int get_nohz_timer_target(void) { int cpu = smp_processor_id(); int i; struct sched_domain *sd; rcu_read_lock(); for_each_domain(cpu, sd) { for_each_cpu(i, sched_domain_span(sd)) { if (!idle_cpu(i)) { cpu = i; goto unlock; } } } unlock: rcu_read_unlock(); return cpu; } void wake_up_idle_cpu(int cpu) { struct rq *rq = cpu_rq(cpu); if (cpu == smp_processor_id()) return; if (rq->curr != rq->idle) return; set_tsk_need_resched(rq->idle); smp_mb(); if (!tsk_is_polling(rq->idle)) smp_send_reschedule(cpu); } static inline bool got_nohz_idle_kick(void) { int cpu = smp_processor_id(); return idle_cpu(cpu) && test_bit(NOHZ_BALANCE_KICK, nohz_flags(cpu)); } #else static inline bool got_nohz_idle_kick(void) { return false; } #endif void sched_avg_update(struct rq *rq) { s64 period = sched_avg_period(); while ((s64)(rq->clock - rq->age_stamp) > period) { asm("" : "+rm" (rq->age_stamp)); rq->age_stamp += period; rq->rt_avg /= 2; } } #else void resched_task(struct task_struct *p) { assert_raw_spin_locked(&task_rq(p)->lock); set_tsk_need_resched(p); } #endif #if defined(CONFIG_RT_GROUP_SCHED) || (defined(CONFIG_FAIR_GROUP_SCHED) && \ (defined(CONFIG_SMP) || defined(CONFIG_CFS_BANDWIDTH))) int walk_tg_tree_from(struct task_group *from, tg_visitor down, tg_visitor up, void *data) { struct task_group *parent, *child; int ret; parent = from; down: ret = (*down)(parent, data); if (ret) goto out; list_for_each_entry_rcu(child, &parent->children, siblings) { parent = child; goto down; up: continue; } ret = (*up)(parent, data); if (ret || parent == from) goto out; child = parent; parent = parent->parent; if (parent) goto up; out: return ret; } int tg_nop(struct task_group *tg, void *data) { return 0; } #endif void update_cpu_load(struct rq *this_rq); static void set_load_weight(struct task_struct *p) { int prio = p->static_prio - MAX_RT_PRIO; struct load_weight *load = &p->se.load; if (p->policy == SCHED_IDLE) { load->weight = scale_load(WEIGHT_IDLEPRIO); load->inv_weight = WMULT_IDLEPRIO; return; } load->weight = scale_load(prio_to_weight[prio]); load->inv_weight = prio_to_wmult[prio]; } static void enqueue_task(struct rq *rq, struct task_struct *p, int flags) { update_rq_clock(rq); sched_info_queued(p); p->sched_class->enqueue_task(rq, p, flags); } static void dequeue_task(struct rq *rq, struct task_struct *p, int flags) { update_rq_clock(rq); sched_info_dequeued(p); p->sched_class->dequeue_task(rq, p, flags); } void activate_task(struct rq *rq, struct task_struct *p, int flags) { if (task_contributes_to_load(p)) rq->nr_uninterruptible--; enqueue_task(rq, p, flags); } void deactivate_task(struct rq *rq, struct task_struct *p, int flags) { if (task_contributes_to_load(p)) rq->nr_uninterruptible++; dequeue_task(rq, p, flags); } #ifdef CONFIG_IRQ_TIME_ACCOUNTING static DEFINE_PER_CPU(u64, cpu_hardirq_time); static DEFINE_PER_CPU(u64, cpu_softirq_time); static DEFINE_PER_CPU(u64, irq_start_time); static int sched_clock_irqtime; void enable_sched_clock_irqtime(void) { sched_clock_irqtime = 1; } void disable_sched_clock_irqtime(void) { sched_clock_irqtime = 0; } #ifndef CONFIG_64BIT static DEFINE_PER_CPU(seqcount_t, irq_time_seq); static inline void irq_time_write_begin(void) { __this_cpu_inc(irq_time_seq.sequence); smp_wmb(); } static inline void irq_time_write_end(void) { smp_wmb(); __this_cpu_inc(irq_time_seq.sequence); } static inline u64 irq_time_read(int cpu) { u64 irq_time; unsigned seq; do { seq = read_seqcount_begin(&per_cpu(irq_time_seq, cpu)); irq_time = per_cpu(cpu_softirq_time, cpu) + per_cpu(cpu_hardirq_time, cpu); } while (read_seqcount_retry(&per_cpu(irq_time_seq, cpu), seq)); return irq_time; } #else static inline void irq_time_write_begin(void) { } static inline void irq_time_write_end(void) { } static inline u64 irq_time_read(int cpu) { return per_cpu(cpu_softirq_time, cpu) + per_cpu(cpu_hardirq_time, cpu); } #endif void account_system_vtime(struct task_struct *curr) { unsigned long flags; s64 delta; int cpu; if (!sched_clock_irqtime) return; local_irq_save(flags); cpu = smp_processor_id(); delta = sched_clock_cpu(cpu) - __this_cpu_read(irq_start_time); __this_cpu_add(irq_start_time, delta); irq_time_write_begin(); if (hardirq_count()) __this_cpu_add(cpu_hardirq_time, delta); else if (in_serving_softirq() && curr != this_cpu_ksoftirqd()) __this_cpu_add(cpu_softirq_time, delta); irq_time_write_end(); local_irq_restore(flags); } EXPORT_SYMBOL_GPL(account_system_vtime); #endif #ifdef CONFIG_PARAVIRT static inline u64 steal_ticks(u64 steal) { if (unlikely(steal > NSEC_PER_SEC)) return div_u64(steal, TICK_NSEC); return __iter_div_u64_rem(steal, TICK_NSEC, &steal); } #endif static void update_rq_clock_task(struct rq *rq, s64 delta) { #if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING) s64 steal = 0, irq_delta = 0; #endif #ifdef CONFIG_IRQ_TIME_ACCOUNTING irq_delta = irq_time_read(cpu_of(rq)) - rq->prev_irq_time; if (irq_delta > delta) irq_delta = delta; rq->prev_irq_time += irq_delta; delta -= irq_delta; #endif #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING if (static_key_false((¶virt_steal_rq_enabled))) { u64 st; steal = paravirt_steal_clock(cpu_of(rq)); steal -= rq->prev_steal_time_rq; if (unlikely(steal > delta)) steal = delta; st = steal_ticks(steal); steal = st * TICK_NSEC; rq->prev_steal_time_rq += steal; delta -= steal; } #endif rq->clock_task += delta; #if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING) if ((irq_delta + steal) && sched_feat(NONTASK_POWER)) sched_rt_avg_update(rq, irq_delta + steal); #endif } #ifdef CONFIG_IRQ_TIME_ACCOUNTING static int irqtime_account_hi_update(void) { u64 *cpustat = kcpustat_this_cpu->cpustat; unsigned long flags; u64 latest_ns; int ret = 0; local_irq_save(flags); latest_ns = this_cpu_read(cpu_hardirq_time); if (nsecs_to_cputime64(latest_ns) > cpustat[CPUTIME_IRQ]) ret = 1; local_irq_restore(flags); return ret; } static int irqtime_account_si_update(void) { u64 *cpustat = kcpustat_this_cpu->cpustat; unsigned long flags; u64 latest_ns; int ret = 0; local_irq_save(flags); latest_ns = this_cpu_read(cpu_softirq_time); if (nsecs_to_cputime64(latest_ns) > cpustat[CPUTIME_SOFTIRQ]) ret = 1; local_irq_restore(flags); return ret; } #else #define sched_clock_irqtime (0) #endif void sched_set_stop_task(int cpu, struct task_struct *stop) { struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 }; struct task_struct *old_stop = cpu_rq(cpu)->stop; if (stop) { sched_setscheduler_nocheck(stop, SCHED_FIFO, ¶m); stop->sched_class = &stop_sched_class; } cpu_rq(cpu)->stop = stop; if (old_stop) { old_stop->sched_class = &rt_sched_class; } } static inline int __normal_prio(struct task_struct *p) { return p->static_prio; } static inline int normal_prio(struct task_struct *p) { int prio; if (task_has_rt_policy(p)) prio = MAX_RT_PRIO-1 - p->rt_priority; else prio = __normal_prio(p); return prio; } static int effective_prio(struct task_struct *p) { p->normal_prio = normal_prio(p); if (!rt_prio(p->prio)) return p->normal_prio; return p->prio; } inline int task_curr(const struct task_struct *p) { return cpu_curr(task_cpu(p)) == p; } static inline void check_class_changed(struct rq *rq, struct task_struct *p, const struct sched_class *prev_class, int oldprio) { if (prev_class != p->sched_class) { if (prev_class->switched_from) prev_class->switched_from(rq, p); p->sched_class->switched_to(rq, p); } else if (oldprio != p->prio) p->sched_class->prio_changed(rq, p, oldprio); } void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags) { const struct sched_class *class; if (p->sched_class == rq->curr->sched_class) { rq->curr->sched_class->check_preempt_curr(rq, p, flags); } else { for_each_class(class) { if (class == rq->curr->sched_class) break; if (class == p->sched_class) { resched_task(rq->curr); break; } } } if (rq->curr->on_rq && test_tsk_need_resched(rq->curr)) rq->skip_clock_update = 1; } #ifdef CONFIG_SMP void set_task_cpu(struct task_struct *p, unsigned int new_cpu) { #ifdef CONFIG_SCHED_DEBUG WARN_ON_ONCE(p->state != TASK_RUNNING && p->state != TASK_WAKING && !(task_thread_info(p)->preempt_count & PREEMPT_ACTIVE)); #ifdef CONFIG_LOCKDEP WARN_ON_ONCE(debug_locks && !(lockdep_is_held(&p->pi_lock) || lockdep_is_held(&task_rq(p)->lock))); #endif #endif trace_sched_migrate_task(p, new_cpu); if (task_cpu(p) != new_cpu) { p->se.nr_migrations++; perf_sw_event(PERF_COUNT_SW_CPU_MIGRATIONS, 1, NULL, 0); } __set_task_cpu(p, new_cpu); } struct migration_arg { struct task_struct *task; int dest_cpu; }; static int migration_cpu_stop(void *data); unsigned long wait_task_inactive(struct task_struct *p, long match_state) { unsigned long flags; int running, on_rq; unsigned long ncsw; struct rq *rq; for (;;) { rq = task_rq(p); while (task_running(rq, p)) { if (match_state && unlikely(p->state != match_state)) return 0; cpu_relax(); } rq = task_rq_lock(p, &flags); trace_sched_wait_task(p); running = task_running(rq, p); on_rq = p->on_rq; ncsw = 0; if (!match_state || p->state == match_state) ncsw = p->nvcsw | LONG_MIN; task_rq_unlock(rq, p, &flags); if (unlikely(!ncsw)) break; if (unlikely(running)) { cpu_relax(); continue; } if (unlikely(on_rq)) { ktime_t to = ktime_set(0, NSEC_PER_MSEC); set_current_state(TASK_UNINTERRUPTIBLE); schedule_hrtimeout(&to, HRTIMER_MODE_REL); continue; } break; } return ncsw; } void kick_process(struct task_struct *p) { int cpu; preempt_disable(); cpu = task_cpu(p); if ((cpu != smp_processor_id()) && task_curr(p)) smp_send_reschedule(cpu); preempt_enable(); } EXPORT_SYMBOL_GPL(kick_process); #endif #ifdef CONFIG_SMP static int select_fallback_rq(int cpu, struct task_struct *p) { const struct cpumask *nodemask = cpumask_of_node(cpu_to_node(cpu)); enum { cpuset, possible, fail } state = cpuset; int dest_cpu; for_each_cpu(dest_cpu, nodemask) { if (!cpu_online(dest_cpu)) continue; if (!cpu_active(dest_cpu)) continue; if (cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p))) return dest_cpu; } for (;;) { for_each_cpu(dest_cpu, tsk_cpus_allowed(p)) { if (!cpu_online(dest_cpu)) continue; if (!cpu_active(dest_cpu)) continue; goto out; } switch (state) { case cpuset: cpuset_cpus_allowed_fallback(p); state = possible; break; case possible: do_set_cpus_allowed(p, cpu_possible_mask); state = fail; break; case fail: BUG(); break; } } out: if (state != cpuset) { if (p->mm && printk_ratelimit()) { printk_deferred("process %d (%s) no longer affine to cpu%d\n", task_pid_nr(p), p->comm, cpu); } } return dest_cpu; } static inline int select_task_rq(struct task_struct *p, int sd_flags, int wake_flags) { int cpu = p->sched_class->select_task_rq(p, sd_flags, wake_flags); if (unlikely(!cpumask_test_cpu(cpu, tsk_cpus_allowed(p)) || !cpu_online(cpu))) cpu = select_fallback_rq(task_cpu(p), p); return cpu; } static void update_avg(u64 *avg, u64 sample) { s64 diff = sample - *avg; *avg += diff >> 3; } #endif static void ttwu_stat(struct task_struct *p, int cpu, int wake_flags) { #ifdef CONFIG_SCHEDSTATS struct rq *rq = this_rq(); #ifdef CONFIG_SMP int this_cpu = smp_processor_id(); if (cpu == this_cpu) { schedstat_inc(rq, ttwu_local); schedstat_inc(p, se.statistics.nr_wakeups_local); } else { struct sched_domain *sd; schedstat_inc(p, se.statistics.nr_wakeups_remote); rcu_read_lock(); for_each_domain(this_cpu, sd) { if (cpumask_test_cpu(cpu, sched_domain_span(sd))) { schedstat_inc(sd, ttwu_wake_remote); break; } } rcu_read_unlock(); } if (wake_flags & WF_MIGRATED) schedstat_inc(p, se.statistics.nr_wakeups_migrate); #endif schedstat_inc(rq, ttwu_count); schedstat_inc(p, se.statistics.nr_wakeups); if (wake_flags & WF_SYNC) schedstat_inc(p, se.statistics.nr_wakeups_sync); #endif } static void ttwu_activate(struct rq *rq, struct task_struct *p, int en_flags) { activate_task(rq, p, en_flags); p->on_rq = 1; if (p->flags & PF_WQ_WORKER) wq_worker_waking_up(p, cpu_of(rq)); } static void ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags) { trace_sched_wakeup(p, true); check_preempt_curr(rq, p, wake_flags); p->state = TASK_RUNNING; #ifdef CONFIG_SMP if (p->sched_class->task_woken) p->sched_class->task_woken(rq, p); if (rq->idle_stamp) { u64 delta = rq->clock - rq->idle_stamp; u64 max = 2*sysctl_sched_migration_cost; if (delta > max) rq->avg_idle = max; else update_avg(&rq->avg_idle, delta); rq->idle_stamp = 0; } #endif } static void ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags) { #ifdef CONFIG_SMP if (p->sched_contributes_to_load) rq->nr_uninterruptible--; #endif ttwu_activate(rq, p, ENQUEUE_WAKEUP | ENQUEUE_WAKING); ttwu_do_wakeup(rq, p, wake_flags); } static int ttwu_remote(struct task_struct *p, int wake_flags) { struct rq *rq; int ret = 0; rq = __task_rq_lock(p); if (p->on_rq) { ttwu_do_wakeup(rq, p, wake_flags); ret = 1; } __task_rq_unlock(rq); return ret; } #ifdef CONFIG_SMP static void sched_ttwu_pending(void) { struct rq *rq = this_rq(); struct llist_node *llist = llist_del_all(&rq->wake_list); struct task_struct *p; raw_spin_lock(&rq->lock); while (llist) { p = llist_entry(llist, struct task_struct, wake_entry); llist = llist_next(llist); ttwu_do_activate(rq, p, 0); } raw_spin_unlock(&rq->lock); } void scheduler_ipi(void) { if (llist_empty(&this_rq()->wake_list) && !got_nohz_idle_kick()) return; irq_enter(); sched_ttwu_pending(); if (unlikely(got_nohz_idle_kick() && !need_resched())) { this_rq()->idle_balance = 1; raise_softirq_irqoff(SCHED_SOFTIRQ); } irq_exit(); } static void ttwu_queue_remote(struct task_struct *p, int cpu) { if (llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list)) smp_send_reschedule(cpu); } #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW static int ttwu_activate_remote(struct task_struct *p, int wake_flags) { struct rq *rq; int ret = 0; rq = __task_rq_lock(p); if (p->on_cpu) { ttwu_activate(rq, p, ENQUEUE_WAKEUP); ttwu_do_wakeup(rq, p, wake_flags); ret = 1; } __task_rq_unlock(rq); return ret; } #endif bool cpus_share_cache(int this_cpu, int that_cpu) { return per_cpu(sd_llc_id, this_cpu) == per_cpu(sd_llc_id, that_cpu); } #endif static void ttwu_queue(struct task_struct *p, int cpu) { struct rq *rq = cpu_rq(cpu); #if defined(CONFIG_SMP) if (sched_feat(TTWU_QUEUE) && !cpus_share_cache(smp_processor_id(), cpu)) { sched_clock_cpu(cpu); ttwu_queue_remote(p, cpu); return; } #endif raw_spin_lock(&rq->lock); ttwu_do_activate(rq, p, 0); raw_spin_unlock(&rq->lock); } static int try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags) { unsigned long flags; int cpu, src_cpu, success = 0; smp_wmb(); raw_spin_lock_irqsave(&p->pi_lock, flags); src_cpu = task_cpu(p); cpu = src_cpu; if (!(p->state & state)) goto out; success = 1; /* we're going to change ->state */ if (p->on_rq && ttwu_remote(p, wake_flags)) goto stat; #ifdef CONFIG_SMP while (p->on_cpu) { #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW if (ttwu_activate_remote(p, wake_flags)) goto stat; #else cpu_relax(); #endif } smp_rmb(); p->sched_contributes_to_load = !!task_contributes_to_load(p); p->state = TASK_WAKING; if (p->sched_class->task_waking) p->sched_class->task_waking(p); cpu = select_task_rq(p, SD_BALANCE_WAKE, wake_flags); if (src_cpu != cpu) { wake_flags |= WF_MIGRATED; set_task_cpu(p, cpu); } #endif ttwu_queue(p, cpu); stat: ttwu_stat(p, cpu, wake_flags); out: raw_spin_unlock_irqrestore(&p->pi_lock, flags); if (src_cpu != cpu && task_notify_on_migrate(p)) atomic_notifier_call_chain(&migration_notifier_head, cpu, (void *)src_cpu); return success; } static void try_to_wake_up_local(struct task_struct *p) { struct rq *rq = task_rq(p); if (WARN_ON(rq != this_rq()) || WARN_ON(p == current)) return; lockdep_assert_held(&rq->lock); if (!raw_spin_trylock(&p->pi_lock)) { raw_spin_unlock(&rq->lock); raw_spin_lock(&p->pi_lock); raw_spin_lock(&rq->lock); } if (!(p->state & TASK_NORMAL)) goto out; if (!p->on_rq) ttwu_activate(rq, p, ENQUEUE_WAKEUP); ttwu_do_wakeup(rq, p, 0); ttwu_stat(p, smp_processor_id(), 0); out: raw_spin_unlock(&p->pi_lock); } int wake_up_process(struct task_struct *p) { return try_to_wake_up(p, TASK_ALL, 0); } EXPORT_SYMBOL(wake_up_process); int wake_up_state(struct task_struct *p, unsigned int state) { return try_to_wake_up(p, state, 0); } static void __sched_fork(struct task_struct *p) { p->on_rq = 0; p->se.on_rq = 0; p->se.exec_start = 0; p->se.sum_exec_runtime = 0; p->se.prev_sum_exec_runtime = 0; p->se.nr_migrations = 0; p->se.vruntime = 0; INIT_LIST_HEAD(&p->se.group_node); #ifdef CONFIG_SCHEDSTATS memset(&p->se.statistics, 0, sizeof(p->se.statistics)); #endif INIT_LIST_HEAD(&p->rt.run_list); #ifdef CONFIG_PREEMPT_NOTIFIERS INIT_HLIST_HEAD(&p->preempt_notifiers); #endif } void sched_fork(struct task_struct *p) { unsigned long flags; int cpu = get_cpu(); __sched_fork(p); p->state = TASK_RUNNING; p->prio = current->normal_prio; if (unlikely(p->sched_reset_on_fork)) { if (task_has_rt_policy(p)) { p->policy = SCHED_NORMAL; p->static_prio = NICE_TO_PRIO(0); p->rt_priority = 0; } else if (PRIO_TO_NICE(p->static_prio) < 0) p->static_prio = NICE_TO_PRIO(0); p->prio = p->normal_prio = __normal_prio(p); set_load_weight(p); p->sched_reset_on_fork = 0; } if (!rt_prio(p->prio)) p->sched_class = &fair_sched_class; if (p->sched_class->task_fork) p->sched_class->task_fork(p); raw_spin_lock_irqsave(&p->pi_lock, flags); set_task_cpu(p, cpu); raw_spin_unlock_irqrestore(&p->pi_lock, flags); #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) if (likely(sched_info_on())) memset(&p->sched_info, 0, sizeof(p->sched_info)); #endif #if defined(CONFIG_SMP) p->on_cpu = 0; #endif #ifdef CONFIG_PREEMPT_COUNT task_thread_info(p)->preempt_count = 1; #endif #ifdef CONFIG_SMP plist_node_init(&p->pushable_tasks, MAX_PRIO); #endif put_cpu(); } void wake_up_new_task(struct task_struct *p) { unsigned long flags; struct rq *rq; raw_spin_lock_irqsave(&p->pi_lock, flags); #ifdef CONFIG_SMP set_task_cpu(p, select_task_rq(p, SD_BALANCE_FORK, 0)); #endif rq = __task_rq_lock(p); activate_task(rq, p, 0); p->on_rq = 1; trace_sched_wakeup_new(p, true); check_preempt_curr(rq, p, WF_FORK); #ifdef CONFIG_SMP if (p->sched_class->task_woken) p->sched_class->task_woken(rq, p); #endif task_rq_unlock(rq, p, &flags); } #ifdef CONFIG_PREEMPT_NOTIFIERS void preempt_notifier_register(struct preempt_notifier *notifier) { hlist_add_head(¬ifier->link, ¤t->preempt_notifiers); } EXPORT_SYMBOL_GPL(preempt_notifier_register); void preempt_notifier_unregister(struct preempt_notifier *notifier) { hlist_del(¬ifier->link); } EXPORT_SYMBOL_GPL(preempt_notifier_unregister); static void fire_sched_in_preempt_notifiers(struct task_struct *curr) { struct preempt_notifier *notifier; struct hlist_node *node; hlist_for_each_entry(notifier, node, &curr->preempt_notifiers, link) notifier->ops->sched_in(notifier, raw_smp_processor_id()); } static void fire_sched_out_preempt_notifiers(struct task_struct *curr, struct task_struct *next) { struct preempt_notifier *notifier; struct hlist_node *node; hlist_for_each_entry(notifier, node, &curr->preempt_notifiers, link) notifier->ops->sched_out(notifier, next); } #else static void fire_sched_in_preempt_notifiers(struct task_struct *curr) { } static void fire_sched_out_preempt_notifiers(struct task_struct *curr, struct task_struct *next) { } #endif static inline void prepare_task_switch(struct rq *rq, struct task_struct *prev, struct task_struct *next) { sched_info_switch(prev, next); perf_event_task_sched_out(prev, next); fire_sched_out_preempt_notifiers(prev, next); prepare_lock_switch(rq, next); prepare_arch_switch(next); trace_sched_switch(prev, next); } static void finish_task_switch(struct rq *rq, struct task_struct *prev) __releases(rq->lock) { struct mm_struct *mm = rq->prev_mm; long prev_state; rq->prev_mm = NULL; prev_state = prev->state; finish_arch_switch(prev); #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW local_irq_disable(); #endif perf_event_task_sched_in(prev, current); #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW local_irq_enable(); #endif finish_lock_switch(rq, prev); finish_arch_post_lock_switch(); fire_sched_in_preempt_notifiers(current); if (mm) mmdrop(mm); if (unlikely(prev_state == TASK_DEAD)) { kprobe_flush_task(prev); put_task_struct(prev); } } #ifdef CONFIG_SMP static inline void pre_schedule(struct rq *rq, struct task_struct *prev) { if (prev->sched_class->pre_schedule) prev->sched_class->pre_schedule(rq, prev); } static inline void post_schedule(struct rq *rq) { if (rq->post_schedule) { unsigned long flags; raw_spin_lock_irqsave(&rq->lock, flags); if (rq->curr->sched_class->post_schedule) rq->curr->sched_class->post_schedule(rq); raw_spin_unlock_irqrestore(&rq->lock, flags); rq->post_schedule = 0; } } #else static inline void pre_schedule(struct rq *rq, struct task_struct *p) { } static inline void post_schedule(struct rq *rq) { } #endif asmlinkage void schedule_tail(struct task_struct *prev) __releases(rq->lock) { struct rq *rq = this_rq(); finish_task_switch(rq, prev); post_schedule(rq); #ifdef __ARCH_WANT_UNLOCKED_CTXSW preempt_enable(); #endif if (current->set_child_tid) put_user(task_pid_vnr(current), current->set_child_tid); } static inline void context_switch(struct rq *rq, struct task_struct *prev, struct task_struct *next) { struct mm_struct *mm, *oldmm; prepare_task_switch(rq, prev, next); mm = next->mm; oldmm = prev->active_mm; arch_start_context_switch(prev); if (!mm) { next->active_mm = oldmm; atomic_inc(&oldmm->mm_count); enter_lazy_tlb(oldmm, next); } else switch_mm(oldmm, mm, next); if (!prev->mm) { prev->active_mm = NULL; rq->prev_mm = oldmm; } #ifndef __ARCH_WANT_UNLOCKED_CTXSW spin_release(&rq->lock.dep_map, 1, _THIS_IP_); #endif switch_to(prev, next, prev); barrier(); finish_task_switch(this_rq(), prev); } unsigned long nr_running(void) { unsigned long i, sum = 0; for_each_online_cpu(i) sum += cpu_rq(i)->nr_running; return sum; } unsigned long nr_uninterruptible(void) { unsigned long i, sum = 0; for_each_possible_cpu(i) sum += cpu_rq(i)->nr_uninterruptible; if (unlikely((long)sum < 0)) sum = 0; return sum; } unsigned long long nr_context_switches(void) { int i; unsigned long long sum = 0; for_each_possible_cpu(i) sum += cpu_rq(i)->nr_switches; return sum; } unsigned long nr_iowait(void) { unsigned long i, sum = 0; for_each_possible_cpu(i) sum += atomic_read(&cpu_rq(i)->nr_iowait); return sum; } unsigned long nr_iowait_cpu(int cpu) { struct rq *this = cpu_rq(cpu); return atomic_read(&this->nr_iowait); } unsigned long this_cpu_load(void) { struct rq *this = this_rq(); return this->cpu_load[0]; } unsigned long avg_nr_running(void) { unsigned long i, sum = 0; unsigned int seqcnt, ave_nr_running; for_each_online_cpu(i) { struct rq *q = cpu_rq(i); /* * Update average to avoid reading stalled value if there were * no run-queue changes for a long time. On the other hand if * the changes are happening right now, just read current value * directly. */ seqcnt = read_seqcount_begin(&q->ave_seqcnt); ave_nr_running = do_avg_nr_running(q); if (read_seqcount_retry(&q->ave_seqcnt, seqcnt)) { read_seqcount_begin(&q->ave_seqcnt); ave_nr_running = q->ave_nr_running; } sum += ave_nr_running; } return sum; } unsigned long get_avg_nr_running(unsigned int cpu) { struct rq *q; if (cpu >= nr_cpu_ids) return 0; q = cpu_rq(cpu); return q->ave_nr_running; } static atomic_long_t calc_load_tasks; static unsigned long calc_load_update; unsigned long avenrun[3]; EXPORT_SYMBOL(avenrun); void get_avenrun(unsigned long *loads, unsigned long offset, int shift) { loads[0] = (avenrun[0] + offset) << shift; loads[1] = (avenrun[1] + offset) << shift; loads[2] = (avenrun[2] + offset) << shift; } static long calc_load_fold_active(struct rq *this_rq) { long nr_active, delta = 0; nr_active = this_rq->nr_running; nr_active += (long) this_rq->nr_uninterruptible; if (nr_active != this_rq->calc_load_active) { delta = nr_active - this_rq->calc_load_active; this_rq->calc_load_active = nr_active; } return delta; } static unsigned long calc_load(unsigned long load, unsigned long exp, unsigned long active) { load *= exp; load += active * (FIXED_1 - exp); load += 1UL << (FSHIFT - 1); return load >> FSHIFT; } #ifdef CONFIG_NO_HZ static atomic_long_t calc_load_idle[2]; static int calc_load_idx; static inline int calc_load_write_idx(void) { int idx = calc_load_idx; smp_rmb(); if (!time_before(jiffies, calc_load_update)) idx++; return idx & 1; } static inline int calc_load_read_idx(void) { return calc_load_idx & 1; } void calc_load_enter_idle(void) { struct rq *this_rq = this_rq(); long delta; delta = calc_load_fold_active(this_rq); if (delta) { int idx = calc_load_write_idx(); atomic_long_add(delta, &calc_load_idle[idx]); } } void calc_load_exit_idle(void) { struct rq *this_rq = this_rq(); if (time_before(jiffies, this_rq->calc_load_update)) return; this_rq->calc_load_update = calc_load_update; if (time_before(jiffies, this_rq->calc_load_update + 10)) this_rq->calc_load_update += LOAD_FREQ; } static long calc_load_fold_idle(void) { int idx = calc_load_read_idx(); long delta = 0; if (atomic_long_read(&calc_load_idle[idx])) delta = atomic_long_xchg(&calc_load_idle[idx], 0); return delta; } static unsigned long fixed_power_int(unsigned long x, unsigned int frac_bits, unsigned int n) { unsigned long result = 1UL << frac_bits; if (n) for (;;) { if (n & 1) { result *= x; result += 1UL << (frac_bits - 1); result >>= frac_bits; } n >>= 1; if (!n) break; x *= x; x += 1UL << (frac_bits - 1); x >>= frac_bits; } return result; } static unsigned long calc_load_n(unsigned long load, unsigned long exp, unsigned long active, unsigned int n) { return calc_load(load, fixed_power_int(exp, FSHIFT, n), active); } static void calc_global_nohz(void) { long delta, active, n; if (!time_before(jiffies, calc_load_update + 10)) { delta = jiffies - calc_load_update - 10; n = 1 + (delta / LOAD_FREQ); active = atomic_long_read(&calc_load_tasks); active = active > 0 ? active * FIXED_1 : 0; avenrun[0] = calc_load_n(avenrun[0], EXP_1, active, n); avenrun[1] = calc_load_n(avenrun[1], EXP_5, active, n); avenrun[2] = calc_load_n(avenrun[2], EXP_15, active, n); calc_load_update += n * LOAD_FREQ; } smp_wmb(); calc_load_idx++; } #else static inline long calc_load_fold_idle(void) { return 0; } static inline void calc_global_nohz(void) { } #endif void calc_global_load(unsigned long ticks) { long active, delta; if (time_before(jiffies, calc_load_update + 10)) return; delta = calc_load_fold_idle(); if (delta) atomic_long_add(delta, &calc_load_tasks); active = atomic_long_read(&calc_load_tasks); active = active > 0 ? active * FIXED_1 : 0; avenrun[0] = calc_load(avenrun[0], EXP_1, active); avenrun[1] = calc_load(avenrun[1], EXP_5, active); avenrun[2] = calc_load(avenrun[2], EXP_15, active); calc_load_update += LOAD_FREQ; calc_global_nohz(); } static void calc_load_account_active(struct rq *this_rq) { long delta; if (time_before(jiffies, this_rq->calc_load_update)) return; delta = calc_load_fold_active(this_rq); if (delta) atomic_long_add(delta, &calc_load_tasks); this_rq->calc_load_update += LOAD_FREQ; } #define DEGRADE_SHIFT 7 static const unsigned char degrade_zero_ticks[CPU_LOAD_IDX_MAX] = {0, 8, 32, 64, 128}; static const unsigned char degrade_factor[CPU_LOAD_IDX_MAX][DEGRADE_SHIFT + 1] = { {0, 0, 0, 0, 0, 0, 0, 0}, {64, 32, 8, 0, 0, 0, 0, 0}, {96, 72, 40, 12, 1, 0, 0}, {112, 98, 75, 43, 15, 1, 0}, {120, 112, 98, 76, 45, 16, 2} }; static unsigned long decay_load_missed(unsigned long load, unsigned long missed_updates, int idx) { int j = 0; if (!missed_updates) return load; if (missed_updates >= degrade_zero_ticks[idx]) return 0; if (idx == 1) return load >> missed_updates; while (missed_updates) { if (missed_updates % 2) load = (load * degrade_factor[idx][j]) >> DEGRADE_SHIFT; missed_updates >>= 1; j++; } return load; } void update_cpu_load(struct rq *this_rq) { unsigned long this_load = this_rq->load.weight; unsigned long curr_jiffies = jiffies; unsigned long pending_updates; int i, scale; this_rq->nr_load_updates++; if (curr_jiffies == this_rq->last_load_update_tick) return; pending_updates = curr_jiffies - this_rq->last_load_update_tick; this_rq->last_load_update_tick = curr_jiffies; this_rq->cpu_load[0] = this_load; for (i = 1, scale = 2; i < CPU_LOAD_IDX_MAX; i++, scale += scale) { unsigned long old_load, new_load; old_load = this_rq->cpu_load[i]; old_load = decay_load_missed(old_load, pending_updates - 1, i); new_load = this_load; if (new_load > old_load) new_load += scale - 1; this_rq->cpu_load[i] = (old_load * (scale - 1) + new_load) >> i; } sched_avg_update(this_rq); } static void update_cpu_load_active(struct rq *this_rq) { update_cpu_load(this_rq); calc_load_account_active(this_rq); } #ifdef CONFIG_SMP void sched_exec(void) { struct task_struct *p = current; unsigned long flags; int dest_cpu; raw_spin_lock_irqsave(&p->pi_lock, flags); dest_cpu = p->sched_class->select_task_rq(p, SD_BALANCE_EXEC, 0); if (dest_cpu == smp_processor_id()) goto unlock; if (likely(cpu_active(dest_cpu))) { struct migration_arg arg = { p, dest_cpu }; raw_spin_unlock_irqrestore(&p->pi_lock, flags); stop_one_cpu(task_cpu(p), migration_cpu_stop, &arg); return; } unlock: raw_spin_unlock_irqrestore(&p->pi_lock, flags); } #endif DEFINE_PER_CPU(struct kernel_stat, kstat); DEFINE_PER_CPU(struct kernel_cpustat, kernel_cpustat); EXPORT_PER_CPU_SYMBOL(kstat); EXPORT_PER_CPU_SYMBOL(kernel_cpustat); static u64 do_task_delta_exec(struct task_struct *p, struct rq *rq) { u64 ns = 0; if (task_current(rq, p)) { update_rq_clock(rq); ns = rq->clock_task - p->se.exec_start; if ((s64)ns < 0) ns = 0; } return ns; } unsigned long long task_delta_exec(struct task_struct *p) { unsigned long flags; struct rq *rq; u64 ns = 0; rq = task_rq_lock(p, &flags); ns = do_task_delta_exec(p, rq); task_rq_unlock(rq, p, &flags); return ns; } unsigned long long task_sched_runtime(struct task_struct *p) { unsigned long flags; struct rq *rq; u64 ns = 0; rq = task_rq_lock(p, &flags); ns = p->se.sum_exec_runtime + do_task_delta_exec(p, rq); task_rq_unlock(rq, p, &flags); return ns; } #ifdef CONFIG_CGROUP_CPUACCT struct cgroup_subsys cpuacct_subsys; struct cpuacct root_cpuacct; #endif static inline void task_group_account_field(struct task_struct *p, int index, u64 tmp) { #ifdef CONFIG_CGROUP_CPUACCT struct kernel_cpustat *kcpustat; struct cpuacct *ca; #endif __get_cpu_var(kernel_cpustat).cpustat[index] += tmp; #ifdef CONFIG_CGROUP_CPUACCT if (unlikely(!cpuacct_subsys.active)) return; rcu_read_lock(); ca = task_ca(p); while (ca && (ca != &root_cpuacct)) { kcpustat = this_cpu_ptr(ca->cpustat); kcpustat->cpustat[index] += tmp; ca = parent_ca(ca); } rcu_read_unlock(); #endif } void account_user_time(struct task_struct *p, cputime_t cputime, cputime_t cputime_scaled) { int index; p->utime += cputime; p->utimescaled += cputime_scaled; account_group_user_time(p, cputime); index = (TASK_NICE(p) > 0) ? CPUTIME_NICE : CPUTIME_USER; task_group_account_field(p, index, (__force u64) cputime); acct_update_integrals(p); } static void account_guest_time(struct task_struct *p, cputime_t cputime, cputime_t cputime_scaled) { u64 *cpustat = kcpustat_this_cpu->cpustat; p->utime += cputime; p->utimescaled += cputime_scaled; account_group_user_time(p, cputime); p->gtime += cputime; if (TASK_NICE(p) > 0) { cpustat[CPUTIME_NICE] += (__force u64) cputime; cpustat[CPUTIME_GUEST_NICE] += (__force u64) cputime; } else { cpustat[CPUTIME_USER] += (__force u64) cputime; cpustat[CPUTIME_GUEST] += (__force u64) cputime; } } static inline void __account_system_time(struct task_struct *p, cputime_t cputime, cputime_t cputime_scaled, int index) { p->stime += cputime; p->stimescaled += cputime_scaled; account_group_system_time(p, cputime); task_group_account_field(p, index, (__force u64) cputime); acct_update_integrals(p); } void account_system_time(struct task_struct *p, int hardirq_offset, cputime_t cputime, cputime_t cputime_scaled) { int index; if ((p->flags & PF_VCPU) && (irq_count() - hardirq_offset == 0)) { account_guest_time(p, cputime, cputime_scaled); return; } if (hardirq_count() - hardirq_offset) index = CPUTIME_IRQ; else if (in_serving_softirq()) index = CPUTIME_SOFTIRQ; else index = CPUTIME_SYSTEM; __account_system_time(p, cputime, cputime_scaled, index); } void account_steal_time(cputime_t cputime) { u64 *cpustat = kcpustat_this_cpu->cpustat; cpustat[CPUTIME_STEAL] += (__force u64) cputime; } void account_idle_time(cputime_t cputime) { u64 *cpustat = kcpustat_this_cpu->cpustat; struct rq *rq = this_rq(); if (atomic_read(&rq->nr_iowait) > 0) cpustat[CPUTIME_IOWAIT] += (__force u64) cputime; else cpustat[CPUTIME_IDLE] += (__force u64) cputime; } static __always_inline bool steal_account_process_tick(void) { #ifdef CONFIG_PARAVIRT if (static_key_false(¶virt_steal_enabled)) { u64 steal, st = 0; steal = paravirt_steal_clock(smp_processor_id()); steal -= this_rq()->prev_steal_time; st = steal_ticks(steal); this_rq()->prev_steal_time += st * TICK_NSEC; account_steal_time(st); return st; } #endif return false; } #ifndef CONFIG_VIRT_CPU_ACCOUNTING #ifdef CONFIG_IRQ_TIME_ACCOUNTING static void irqtime_account_process_tick(struct task_struct *p, int user_tick, struct rq *rq) { cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy); u64 *cpustat = kcpustat_this_cpu->cpustat; if (steal_account_process_tick()) return; if (irqtime_account_hi_update()) { cpustat[CPUTIME_IRQ] += (__force u64) cputime_one_jiffy; } else if (irqtime_account_si_update()) { cpustat[CPUTIME_SOFTIRQ] += (__force u64) cputime_one_jiffy; } else if (this_cpu_ksoftirqd() == p) { __account_system_time(p, cputime_one_jiffy, one_jiffy_scaled, CPUTIME_SOFTIRQ); } else if (user_tick) { account_user_time(p, cputime_one_jiffy, one_jiffy_scaled); } else if (p == rq->idle) { account_idle_time(cputime_one_jiffy); } else if (p->flags & PF_VCPU) { account_guest_time(p, cputime_one_jiffy, one_jiffy_scaled); } else { __account_system_time(p, cputime_one_jiffy, one_jiffy_scaled, CPUTIME_SYSTEM); } } static void irqtime_account_idle_ticks(int ticks) { int i; struct rq *rq = this_rq(); for (i = 0; i < ticks; i++) irqtime_account_process_tick(current, 0, rq); } #else static void irqtime_account_idle_ticks(int ticks) {} static void irqtime_account_process_tick(struct task_struct *p, int user_tick, struct rq *rq) {} #endif void account_process_tick(struct task_struct *p, int user_tick) { cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy); struct rq *rq = this_rq(); if (sched_clock_irqtime) { irqtime_account_process_tick(p, user_tick, rq); return; } if (steal_account_process_tick()) return; if (user_tick) account_user_time(p, cputime_one_jiffy, one_jiffy_scaled); else if ((p != rq->idle) || (irq_count() != HARDIRQ_OFFSET)) account_system_time(p, HARDIRQ_OFFSET, cputime_one_jiffy, one_jiffy_scaled); else account_idle_time(cputime_one_jiffy); } void account_steal_ticks(unsigned long ticks) { account_steal_time(jiffies_to_cputime(ticks)); } void account_idle_ticks(unsigned long ticks) { if (sched_clock_irqtime) { irqtime_account_idle_ticks(ticks); return; } account_idle_time(jiffies_to_cputime(ticks)); } #endif #ifdef CONFIG_VIRT_CPU_ACCOUNTING void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st) { *ut = p->utime; *st = p->stime; } void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st) { struct task_cputime cputime; thread_group_cputime(p, &cputime); *ut = cputime.utime; *st = cputime.stime; } #else #ifndef nsecs_to_cputime # define nsecs_to_cputime(__nsecs) nsecs_to_jiffies(__nsecs) #endif void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st) { cputime_t rtime, utime = p->utime, total = utime + p->stime; rtime = nsecs_to_cputime(p->se.sum_exec_runtime); if (total) { u64 temp = (__force u64) rtime; temp *= (__force u64) utime; do_div(temp, (__force u32) total); utime = (__force cputime_t) temp; } else utime = rtime; p->prev_utime = max(p->prev_utime, utime); p->prev_stime = max(p->prev_stime, rtime - p->prev_utime); *ut = p->prev_utime; *st = p->prev_stime; } void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st) { struct signal_struct *sig = p->signal; struct task_cputime cputime; cputime_t rtime, utime, total; thread_group_cputime(p, &cputime); total = cputime.utime + cputime.stime; rtime = nsecs_to_cputime(cputime.sum_exec_runtime); if (total) { u64 temp = (__force u64) rtime; temp *= (__force u64) cputime.utime; do_div(temp, (__force u32) total); utime = (__force cputime_t) temp; } else utime = rtime; sig->prev_utime = max(sig->prev_utime, utime); sig->prev_stime = max(sig->prev_stime, rtime - sig->prev_utime); *ut = sig->prev_utime; *st = sig->prev_stime; } #endif void scheduler_tick(void) { int cpu = smp_processor_id(); struct rq *rq = cpu_rq(cpu); struct task_struct *curr = rq->curr; sched_clock_tick(); raw_spin_lock(&rq->lock); update_rq_clock(rq); update_cpu_load_active(rq); curr->sched_class->task_tick(rq, curr, 0); raw_spin_unlock(&rq->lock); perf_event_task_tick(); #ifdef CONFIG_SMP rq->idle_balance = idle_cpu(cpu); trigger_load_balance(rq, cpu); #endif } notrace unsigned long get_parent_ip(unsigned long addr) { if (in_lock_functions(addr)) { addr = CALLER_ADDR2; if (in_lock_functions(addr)) addr = CALLER_ADDR3; } return addr; } #if defined(CONFIG_PREEMPT) && (defined(CONFIG_DEBUG_PREEMPT) || \ defined(CONFIG_PREEMPT_TRACER)) void __kprobes add_preempt_count(int val) { #ifdef CONFIG_DEBUG_PREEMPT if (DEBUG_LOCKS_WARN_ON((preempt_count() < 0))) return; #endif preempt_count() += val; #ifdef CONFIG_DEBUG_PREEMPT DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >= PREEMPT_MASK - 10); #endif if (preempt_count() == val) trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1)); } EXPORT_SYMBOL(add_preempt_count); void __kprobes sub_preempt_count(int val) { #ifdef CONFIG_DEBUG_PREEMPT if (DEBUG_LOCKS_WARN_ON(val > preempt_count())) return; if (DEBUG_LOCKS_WARN_ON((val < PREEMPT_MASK) && !(preempt_count() & PREEMPT_MASK))) return; #endif if (preempt_count() == val) trace_preempt_on(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1)); preempt_count() -= val; } EXPORT_SYMBOL(sub_preempt_count); #endif static noinline void __schedule_bug(struct task_struct *prev) { if (oops_in_progress) return; printk(KERN_ERR "BUG: scheduling while atomic: %s/%d/0x%08x\n", prev->comm, prev->pid, preempt_count()); debug_show_held_locks(prev); print_modules(); if (irqs_disabled()) print_irqtrace_events(prev); dump_stack(); } static inline void schedule_debug(struct task_struct *prev) { if (unlikely(in_atomic_preempt_off() && !prev->exit_state)) __schedule_bug(prev); rcu_sleep_check(); profile_hit(SCHED_PROFILING, __builtin_return_address(0)); schedstat_inc(this_rq(), sched_count); } static void put_prev_task(struct rq *rq, struct task_struct *prev) { if (prev->on_rq || rq->skip_clock_update < 0) update_rq_clock(rq); prev->sched_class->put_prev_task(rq, prev); } static inline struct task_struct * pick_next_task(struct rq *rq) { const struct sched_class *class; struct task_struct *p; if (likely(rq->nr_running == rq->cfs.h_nr_running)) { p = fair_sched_class.pick_next_task(rq); if (likely(p)) return p; } for_each_class(class) { p = class->pick_next_task(rq); if (p) return p; } BUG(); } static void __sched __schedule(void) { struct task_struct *prev, *next; unsigned long *switch_count; struct rq *rq; int cpu; need_resched: preempt_disable(); cpu = smp_processor_id(); rq = cpu_rq(cpu); rcu_note_context_switch(cpu); prev = rq->curr; schedule_debug(prev); if (sched_feat(HRTICK)) hrtick_clear(rq); raw_spin_lock_irq(&rq->lock); switch_count = &prev->nivcsw; if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) { if (unlikely(signal_pending_state(prev->state, prev))) { prev->state = TASK_RUNNING; } else { deactivate_task(rq, prev, DEQUEUE_SLEEP); prev->on_rq = 0; if (prev->flags & PF_WQ_WORKER) { struct task_struct *to_wakeup; to_wakeup = wq_worker_sleeping(prev, cpu); if (to_wakeup) try_to_wake_up_local(to_wakeup); } } switch_count = &prev->nvcsw; } pre_schedule(rq, prev); if (unlikely(!rq->nr_running)) idle_balance(cpu, rq); put_prev_task(rq, prev); next = pick_next_task(rq); clear_tsk_need_resched(prev); rq->skip_clock_update = 0; if (likely(prev != next)) { rq->nr_switches++; rq->curr = next; ++*switch_count; context_switch(rq, prev, next); cpu = smp_processor_id(); rq = cpu_rq(cpu); } else raw_spin_unlock_irq(&rq->lock); post_schedule(rq); sched_preempt_enable_no_resched(); if (need_resched()) goto need_resched; } static inline void sched_submit_work(struct task_struct *tsk) { if (!tsk->state || tsk_is_pi_blocked(tsk)) return; if (blk_needs_flush_plug(tsk)) blk_schedule_flush_plug(tsk); } asmlinkage void __sched schedule(void) { struct task_struct *tsk = current; sched_submit_work(tsk); __schedule(); } EXPORT_SYMBOL(schedule); void __sched schedule_preempt_disabled(void) { sched_preempt_enable_no_resched(); schedule(); preempt_disable(); } #ifdef CONFIG_MUTEX_SPIN_ON_OWNER static inline bool owner_running(struct mutex *lock, struct task_struct *owner) { if (lock->owner != owner) return false; barrier(); return owner->on_cpu; } int mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner) { if (!sched_feat(OWNER_SPIN)) return 0; rcu_read_lock(); while (owner_running(lock, owner)) { if (need_resched()) break; arch_mutex_cpu_relax(); } rcu_read_unlock(); return lock->owner == NULL; } #endif #ifdef CONFIG_PREEMPT asmlinkage void __sched notrace preempt_schedule(void) { struct thread_info *ti = current_thread_info(); if (likely(ti->preempt_count || irqs_disabled())) return; do { add_preempt_count_notrace(PREEMPT_ACTIVE); __schedule(); sub_preempt_count_notrace(PREEMPT_ACTIVE); barrier(); } while (need_resched()); } EXPORT_SYMBOL(preempt_schedule); asmlinkage void __sched preempt_schedule_irq(void) { struct thread_info *ti = current_thread_info(); BUG_ON(ti->preempt_count || !irqs_disabled()); do { add_preempt_count(PREEMPT_ACTIVE); local_irq_enable(); __schedule(); local_irq_disable(); sub_preempt_count(PREEMPT_ACTIVE); barrier(); } while (need_resched()); } #endif int default_wake_function(wait_queue_t *curr, unsigned mode, int wake_flags, void *key) { return try_to_wake_up(curr->private, mode, wake_flags); } EXPORT_SYMBOL(default_wake_function); static void __wake_up_common(wait_queue_head_t *q, unsigned int mode, int nr_exclusive, int wake_flags, void *key) { wait_queue_t *curr, *next; list_for_each_entry_safe(curr, next, &q->task_list, task_list) { unsigned flags = curr->flags; if (curr->func(curr, mode, wake_flags, key) && (flags & WQ_FLAG_EXCLUSIVE) && !--nr_exclusive) break; } } void __wake_up(wait_queue_head_t *q, unsigned int mode, int nr_exclusive, void *key) { unsigned long flags; spin_lock_irqsave(&q->lock, flags); __wake_up_common(q, mode, nr_exclusive, 0, key); spin_unlock_irqrestore(&q->lock, flags); } EXPORT_SYMBOL(__wake_up); void __wake_up_locked(wait_queue_head_t *q, unsigned int mode, int nr) { __wake_up_common(q, mode, nr, 0, NULL); } EXPORT_SYMBOL_GPL(__wake_up_locked); void __wake_up_locked_key(wait_queue_head_t *q, unsigned int mode, void *key) { __wake_up_common(q, mode, 1, 0, key); } EXPORT_SYMBOL_GPL(__wake_up_locked_key); void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode, int nr_exclusive, void *key) { unsigned long flags; int wake_flags = WF_SYNC; if (unlikely(!q)) return; if (unlikely(!nr_exclusive)) wake_flags = 0; spin_lock_irqsave(&q->lock, flags); __wake_up_common(q, mode, nr_exclusive, wake_flags, key); spin_unlock_irqrestore(&q->lock, flags); } EXPORT_SYMBOL_GPL(__wake_up_sync_key); void __wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr_exclusive) { __wake_up_sync_key(q, mode, nr_exclusive, NULL); } EXPORT_SYMBOL_GPL(__wake_up_sync); void complete(struct completion *x) { unsigned long flags; spin_lock_irqsave(&x->wait.lock, flags); x->done++; __wake_up_common(&x->wait, TASK_NORMAL, 1, 0, NULL); spin_unlock_irqrestore(&x->wait.lock, flags); } EXPORT_SYMBOL(complete); void complete_all(struct completion *x) { unsigned long flags; spin_lock_irqsave(&x->wait.lock, flags); x->done += UINT_MAX/2; __wake_up_common(&x->wait, TASK_NORMAL, 0, 0, NULL); spin_unlock_irqrestore(&x->wait.lock, flags); } EXPORT_SYMBOL(complete_all); static inline long __sched do_wait_for_common(struct completion *x, long timeout, int state, int iowait) { if (!x->done) { DECLARE_WAITQUEUE(wait, current); __add_wait_queue_tail_exclusive(&x->wait, &wait); do { if (signal_pending_state(state, current)) { timeout = -ERESTARTSYS; break; } __set_current_state(state); spin_unlock_irq(&x->wait.lock); if (iowait) timeout = io_schedule_timeout(timeout); else timeout = schedule_timeout(timeout); spin_lock_irq(&x->wait.lock); } while (!x->done && timeout); __remove_wait_queue(&x->wait, &wait); if (!x->done) return timeout; } x->done--; return timeout ?: 1; } static long __sched wait_for_common(struct completion *x, long timeout, int state, int iowait) { might_sleep(); spin_lock_irq(&x->wait.lock); timeout = do_wait_for_common(x, timeout, state, iowait); spin_unlock_irq(&x->wait.lock); return timeout; } void __sched wait_for_completion(struct completion *x) { wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_UNINTERRUPTIBLE, 0); } EXPORT_SYMBOL(wait_for_completion); void __sched wait_for_completion_io(struct completion *x) { wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_UNINTERRUPTIBLE, 1); } EXPORT_SYMBOL(wait_for_completion_io); unsigned long __sched wait_for_completion_timeout(struct completion *x, unsigned long timeout) { return wait_for_common(x, timeout, TASK_UNINTERRUPTIBLE, 0); } EXPORT_SYMBOL(wait_for_completion_timeout); int __sched wait_for_completion_interruptible(struct completion *x) { long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_INTERRUPTIBLE, 0); if (t == -ERESTARTSYS) return t; return 0; } EXPORT_SYMBOL(wait_for_completion_interruptible); long __sched wait_for_completion_interruptible_timeout(struct completion *x, unsigned long timeout) { return wait_for_common(x, timeout, TASK_INTERRUPTIBLE, 0); } EXPORT_SYMBOL(wait_for_completion_interruptible_timeout); int __sched wait_for_completion_killable(struct completion *x) { long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_KILLABLE, 0); if (t == -ERESTARTSYS) return t; return 0; } EXPORT_SYMBOL(wait_for_completion_killable); long __sched wait_for_completion_killable_timeout(struct completion *x, unsigned long timeout) { return wait_for_common(x, timeout, TASK_KILLABLE, 0); } EXPORT_SYMBOL(wait_for_completion_killable_timeout); bool try_wait_for_completion(struct completion *x) { unsigned long flags; int ret = 1; spin_lock_irqsave(&x->wait.lock, flags); if (!x->done) ret = 0; else x->done--; spin_unlock_irqrestore(&x->wait.lock, flags); return ret; } EXPORT_SYMBOL(try_wait_for_completion); bool completion_done(struct completion *x) { unsigned long flags; int ret = 1; spin_lock_irqsave(&x->wait.lock, flags); if (!x->done) ret = 0; spin_unlock_irqrestore(&x->wait.lock, flags); return ret; } EXPORT_SYMBOL(completion_done); static long __sched sleep_on_common(wait_queue_head_t *q, int state, long timeout) { unsigned long flags; wait_queue_t wait; init_waitqueue_entry(&wait, current); __set_current_state(state); spin_lock_irqsave(&q->lock, flags); __add_wait_queue(q, &wait); spin_unlock(&q->lock); timeout = schedule_timeout(timeout); spin_lock_irq(&q->lock); __remove_wait_queue(q, &wait); spin_unlock_irqrestore(&q->lock, flags); return timeout; } void __sched interruptible_sleep_on(wait_queue_head_t *q) { sleep_on_common(q, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); } EXPORT_SYMBOL(interruptible_sleep_on); long __sched interruptible_sleep_on_timeout(wait_queue_head_t *q, long timeout) { return sleep_on_common(q, TASK_INTERRUPTIBLE, timeout); } EXPORT_SYMBOL(interruptible_sleep_on_timeout); void __sched sleep_on(wait_queue_head_t *q) { sleep_on_common(q, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); } EXPORT_SYMBOL(sleep_on); long __sched sleep_on_timeout(wait_queue_head_t *q, long timeout) { return sleep_on_common(q, TASK_UNINTERRUPTIBLE, timeout); } EXPORT_SYMBOL(sleep_on_timeout); #ifdef CONFIG_RT_MUTEXES void rt_mutex_setprio(struct task_struct *p, int prio) { int oldprio, on_rq, running; struct rq *rq; const struct sched_class *prev_class; BUG_ON(prio < 0 || prio > MAX_PRIO); rq = __task_rq_lock(p); if (unlikely(p == rq->idle)) { WARN_ON(p != rq->curr); WARN_ON(p->pi_blocked_on); goto out_unlock; } trace_sched_pi_setprio(p, prio); oldprio = p->prio; prev_class = p->sched_class; on_rq = p->on_rq; running = task_current(rq, p); if (on_rq) dequeue_task(rq, p, 0); if (running) p->sched_class->put_prev_task(rq, p); if (rt_prio(prio)) p->sched_class = &rt_sched_class; else p->sched_class = &fair_sched_class; p->prio = prio; if (running) p->sched_class->set_curr_task(rq); if (on_rq) enqueue_task(rq, p, oldprio < prio ? ENQUEUE_HEAD : 0); check_class_changed(rq, p, prev_class, oldprio); out_unlock: __task_rq_unlock(rq); } #endif void set_user_nice(struct task_struct *p, long nice) { int old_prio, delta, on_rq; unsigned long flags; struct rq *rq; if (TASK_NICE(p) == nice || nice < -20 || nice > 19) return; rq = task_rq_lock(p, &flags); if (task_has_rt_policy(p)) { p->static_prio = NICE_TO_PRIO(nice); goto out_unlock; } on_rq = p->on_rq; if (on_rq) dequeue_task(rq, p, 0); p->static_prio = NICE_TO_PRIO(nice); set_load_weight(p); old_prio = p->prio; p->prio = effective_prio(p); delta = p->prio - old_prio; if (on_rq) { enqueue_task(rq, p, 0); if (delta < 0 || (delta > 0 && task_running(rq, p))) resched_task(rq->curr); } out_unlock: task_rq_unlock(rq, p, &flags); } EXPORT_SYMBOL(set_user_nice); int can_nice(const struct task_struct *p, const int nice) { int nice_rlim = 20 - nice; return (nice_rlim <= task_rlimit(p, RLIMIT_NICE) || capable(CAP_SYS_NICE)); } #ifdef __ARCH_WANT_SYS_NICE SYSCALL_DEFINE1(nice, int, increment) { long nice, retval; if (increment < -40) increment = -40; if (increment > 40) increment = 40; nice = TASK_NICE(current) + increment; if (nice < -20) nice = -20; if (nice > 19) nice = 19; if (increment < 0 && !can_nice(current, nice)) return -EPERM; retval = security_task_setnice(current, nice); if (retval) return retval; set_user_nice(current, nice); return 0; } #endif int task_prio(const struct task_struct *p) { return p->prio - MAX_RT_PRIO; } int task_nice(const struct task_struct *p) { return TASK_NICE(p); } EXPORT_SYMBOL(task_nice); int idle_cpu(int cpu) { struct rq *rq = cpu_rq(cpu); if (rq->curr != rq->idle) return 0; if (rq->nr_running) return 0; #ifdef CONFIG_SMP if (!llist_empty(&rq->wake_list)) return 0; #endif return 1; } struct task_struct *idle_task(int cpu) { return cpu_rq(cpu)->idle; } static struct task_struct *find_process_by_pid(pid_t pid) { return pid ? find_task_by_vpid(pid) : current; } static void __setscheduler(struct rq *rq, struct task_struct *p, int policy, int prio) { p->policy = policy; p->rt_priority = prio; p->normal_prio = normal_prio(p); p->prio = rt_mutex_getprio(p); if (rt_prio(p->prio)) p->sched_class = &rt_sched_class; else p->sched_class = &fair_sched_class; set_load_weight(p); } static bool check_same_owner(struct task_struct *p) { const struct cred *cred = current_cred(), *pcred; bool match; rcu_read_lock(); pcred = __task_cred(p); if (cred->user->user_ns == pcred->user->user_ns) match = (cred->euid == pcred->euid || cred->euid == pcred->uid); else match = false; rcu_read_unlock(); return match; } static int __sched_setscheduler(struct task_struct *p, int policy, const struct sched_param *param, bool user) { int retval, oldprio, oldpolicy = -1, on_rq, running; unsigned long flags; const struct sched_class *prev_class; struct rq *rq; int reset_on_fork; BUG_ON(in_interrupt()); recheck: if (policy < 0) { reset_on_fork = p->sched_reset_on_fork; policy = oldpolicy = p->policy; } else { reset_on_fork = !!(policy & SCHED_RESET_ON_FORK); policy &= ~SCHED_RESET_ON_FORK; if (policy != SCHED_FIFO && policy != SCHED_RR && policy != SCHED_NORMAL && policy != SCHED_BATCH && policy != SCHED_IDLE) return -EINVAL; } if (param->sched_priority < 0 || (p->mm && param->sched_priority > MAX_USER_RT_PRIO-1) || (!p->mm && param->sched_priority > MAX_RT_PRIO-1)) return -EINVAL; if (rt_policy(policy) != (param->sched_priority != 0)) return -EINVAL; if (user && !capable(CAP_SYS_NICE)) { if (rt_policy(policy)) { unsigned long rlim_rtprio = task_rlimit(p, RLIMIT_RTPRIO); if (policy != p->policy && !rlim_rtprio) return -EPERM; if (param->sched_priority > p->rt_priority && param->sched_priority > rlim_rtprio) return -EPERM; } if (p->policy == SCHED_IDLE && policy != SCHED_IDLE) { if (!can_nice(p, TASK_NICE(p))) return -EPERM; } if (!check_same_owner(p)) return -EPERM; if (p->sched_reset_on_fork && !reset_on_fork) return -EPERM; } if (user) { retval = security_task_setscheduler(p); if (retval) return retval; } rq = task_rq_lock(p, &flags); if (p == rq->stop) { task_rq_unlock(rq, p, &flags); return -EINVAL; } if (unlikely(policy == p->policy && (!rt_policy(policy) || param->sched_priority == p->rt_priority))) { __task_rq_unlock(rq); raw_spin_unlock_irqrestore(&p->pi_lock, flags); return 0; } #ifdef CONFIG_RT_GROUP_SCHED if (user) { if (rt_bandwidth_enabled() && rt_policy(policy) && task_group(p)->rt_bandwidth.rt_runtime == 0 && !task_group_is_autogroup(task_group(p))) { task_rq_unlock(rq, p, &flags); return -EPERM; } } #endif if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) { policy = oldpolicy = -1; task_rq_unlock(rq, p, &flags); goto recheck; } on_rq = p->on_rq; running = task_current(rq, p); if (on_rq) dequeue_task(rq, p, 0); if (running) p->sched_class->put_prev_task(rq, p); p->sched_reset_on_fork = reset_on_fork; oldprio = p->prio; prev_class = p->sched_class; __setscheduler(rq, p, policy, param->sched_priority); if (running) p->sched_class->set_curr_task(rq); if (on_rq) enqueue_task(rq, p, 0); check_class_changed(rq, p, prev_class, oldprio); task_rq_unlock(rq, p, &flags); rt_mutex_adjust_pi(p); return 0; } int sched_setscheduler(struct task_struct *p, int policy, const struct sched_param *param) { return __sched_setscheduler(p, policy, param, true); } EXPORT_SYMBOL(sched_setscheduler); int sched_setscheduler_nocheck(struct task_struct *p, int policy, const struct sched_param *param) { return __sched_setscheduler(p, policy, param, false); } static int do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param) { struct sched_param lparam; struct task_struct *p; int retval; if (!param || pid < 0) return -EINVAL; if (copy_from_user(&lparam, param, sizeof(struct sched_param))) return -EFAULT; rcu_read_lock(); retval = -ESRCH; p = find_process_by_pid(pid); if (p != NULL) retval = sched_setscheduler(p, policy, &lparam); rcu_read_unlock(); return retval; } SYSCALL_DEFINE3(sched_setscheduler, pid_t, pid, int, policy, struct sched_param __user *, param) { if (policy < 0) return -EINVAL; return do_sched_setscheduler(pid, policy, param); } SYSCALL_DEFINE2(sched_setparam, pid_t, pid, struct sched_param __user *, param) { return do_sched_setscheduler(pid, -1, param); } SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid) { struct task_struct *p; int retval; if (pid < 0) return -EINVAL; retval = -ESRCH; rcu_read_lock(); p = find_process_by_pid(pid); if (p) { retval = security_task_getscheduler(p); if (!retval) retval = p->policy | (p->sched_reset_on_fork ? SCHED_RESET_ON_FORK : 0); } rcu_read_unlock(); return retval; } SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param) { struct sched_param lp; struct task_struct *p; int retval; if (!param || pid < 0) return -EINVAL; rcu_read_lock(); p = find_process_by_pid(pid); retval = -ESRCH; if (!p) goto out_unlock; retval = security_task_getscheduler(p); if (retval) goto out_unlock; lp.sched_priority = p->rt_priority; rcu_read_unlock(); retval = copy_to_user(param, &lp, sizeof(*param)) ? -EFAULT : 0; return retval; out_unlock: rcu_read_unlock(); return retval; } long sched_setaffinity(pid_t pid, const struct cpumask *in_mask) { cpumask_var_t cpus_allowed, new_mask; struct task_struct *p; int retval; get_online_cpus(); rcu_read_lock(); p = find_process_by_pid(pid); if (!p) { rcu_read_unlock(); put_online_cpus(); return -ESRCH; } get_task_struct(p); rcu_read_unlock(); if (!alloc_cpumask_var(&cpus_allowed, GFP_KERNEL)) { retval = -ENOMEM; goto out_put_task; } if (!alloc_cpumask_var(&new_mask, GFP_KERNEL)) { retval = -ENOMEM; goto out_free_cpus_allowed; } retval = -EPERM; if (!check_same_owner(p) && !ns_capable(task_user_ns(p), CAP_SYS_NICE)) goto out_unlock; retval = security_task_setscheduler(p); if (retval) goto out_unlock; cpuset_cpus_allowed(p, cpus_allowed); cpumask_and(new_mask, in_mask, cpus_allowed); again: retval = set_cpus_allowed_ptr(p, new_mask); if (!retval) { cpuset_cpus_allowed(p, cpus_allowed); if (!cpumask_subset(new_mask, cpus_allowed)) { cpumask_copy(new_mask, cpus_allowed); goto again; } } out_unlock: free_cpumask_var(new_mask); out_free_cpus_allowed: free_cpumask_var(cpus_allowed); out_put_task: put_task_struct(p); put_online_cpus(); return retval; } EXPORT_SYMBOL_GPL(sched_setaffinity); static int get_user_cpu_mask(unsigned long __user *user_mask_ptr, unsigned len, struct cpumask *new_mask) { if (len < cpumask_size()) cpumask_clear(new_mask); else if (len > cpumask_size()) len = cpumask_size(); return copy_from_user(new_mask, user_mask_ptr, len) ? -EFAULT : 0; } SYSCALL_DEFINE3(sched_setaffinity, pid_t, pid, unsigned int, len, unsigned long __user *, user_mask_ptr) { cpumask_var_t new_mask; int retval; if (!alloc_cpumask_var(&new_mask, GFP_KERNEL)) return -ENOMEM; retval = get_user_cpu_mask(user_mask_ptr, len, new_mask); if (retval == 0) retval = sched_setaffinity(pid, new_mask); free_cpumask_var(new_mask); return retval; } long sched_getaffinity(pid_t pid, struct cpumask *mask) { struct task_struct *p; unsigned long flags; int retval; get_online_cpus(); rcu_read_lock(); retval = -ESRCH; p = find_process_by_pid(pid); if (!p) goto out_unlock; retval = security_task_getscheduler(p); if (retval) goto out_unlock; raw_spin_lock_irqsave(&p->pi_lock, flags); cpumask_and(mask, &p->cpus_allowed, cpu_online_mask); raw_spin_unlock_irqrestore(&p->pi_lock, flags); out_unlock: rcu_read_unlock(); put_online_cpus(); return retval; } SYSCALL_DEFINE3(sched_getaffinity, pid_t, pid, unsigned int, len, unsigned long __user *, user_mask_ptr) { int ret; cpumask_var_t mask; if ((len * BITS_PER_BYTE) < nr_cpu_ids) return -EINVAL; if (len & (sizeof(unsigned long)-1)) return -EINVAL; if (!alloc_cpumask_var(&mask, GFP_KERNEL)) return -ENOMEM; ret = sched_getaffinity(pid, mask); if (ret == 0) { size_t retlen = min_t(size_t, len, cpumask_size()); if (copy_to_user(user_mask_ptr, mask, retlen)) ret = -EFAULT; else ret = retlen; } free_cpumask_var(mask); return ret; } SYSCALL_DEFINE0(sched_yield) { struct rq *rq = this_rq_lock(); schedstat_inc(rq, yld_count); current->sched_class->yield_task(rq); __release(rq->lock); spin_release(&rq->lock.dep_map, 1, _THIS_IP_); do_raw_spin_unlock(&rq->lock); sched_preempt_enable_no_resched(); schedule(); return 0; } static inline int should_resched(void) { return need_resched() && !(preempt_count() & PREEMPT_ACTIVE); } static void __cond_resched(void) { add_preempt_count(PREEMPT_ACTIVE); __schedule(); sub_preempt_count(PREEMPT_ACTIVE); } int __sched _cond_resched(void) { if (should_resched()) { __cond_resched(); return 1; } return 0; } EXPORT_SYMBOL(_cond_resched); int __cond_resched_lock(spinlock_t *lock) { int resched = should_resched(); int ret = 0; lockdep_assert_held(lock); if (spin_needbreak(lock) || resched) { spin_unlock(lock); if (resched) __cond_resched(); else cpu_relax(); ret = 1; spin_lock(lock); } return ret; } EXPORT_SYMBOL(__cond_resched_lock); int __sched __cond_resched_softirq(void) { BUG_ON(!in_softirq()); if (should_resched()) { local_bh_enable(); __cond_resched(); local_bh_disable(); return 1; } return 0; } EXPORT_SYMBOL(__cond_resched_softirq); void __sched yield(void) { set_current_state(TASK_RUNNING); sys_sched_yield(); } EXPORT_SYMBOL(yield); bool __sched yield_to(struct task_struct *p, bool preempt) { struct task_struct *curr = current; struct rq *rq, *p_rq; unsigned long flags; bool yielded = 0; local_irq_save(flags); rq = this_rq(); again: p_rq = task_rq(p); double_rq_lock(rq, p_rq); while (task_rq(p) != p_rq) { double_rq_unlock(rq, p_rq); goto again; } if (!curr->sched_class->yield_to_task) goto out; if (curr->sched_class != p->sched_class) goto out; if (task_running(p_rq, p) || p->state) goto out; yielded = curr->sched_class->yield_to_task(rq, p, preempt); if (yielded) { schedstat_inc(rq, yld_count); if (preempt && rq != p_rq) resched_task(p_rq->curr); } else { rq->skip_clock_update = 0; } out: double_rq_unlock(rq, p_rq); local_irq_restore(flags); if (yielded) schedule(); return yielded; } EXPORT_SYMBOL_GPL(yield_to); void __sched io_schedule(void) { struct rq *rq = raw_rq(); delayacct_blkio_start(); atomic_inc(&rq->nr_iowait); blk_flush_plug(current); current->in_iowait = 1; schedule(); current->in_iowait = 0; atomic_dec(&rq->nr_iowait); delayacct_blkio_end(); } EXPORT_SYMBOL(io_schedule); long __sched io_schedule_timeout(long timeout) { struct rq *rq = raw_rq(); long ret; delayacct_blkio_start(); atomic_inc(&rq->nr_iowait); blk_flush_plug(current); current->in_iowait = 1; ret = schedule_timeout(timeout); current->in_iowait = 0; atomic_dec(&rq->nr_iowait); delayacct_blkio_end(); return ret; } SYSCALL_DEFINE1(sched_get_priority_max, int, policy) { int ret = -EINVAL; switch (policy) { case SCHED_FIFO: case SCHED_RR: ret = MAX_USER_RT_PRIO-1; break; case SCHED_NORMAL: case SCHED_BATCH: case SCHED_IDLE: ret = 0; break; } return ret; } SYSCALL_DEFINE1(sched_get_priority_min, int, policy) { int ret = -EINVAL; switch (policy) { case SCHED_FIFO: case SCHED_RR: ret = 1; break; case SCHED_NORMAL: case SCHED_BATCH: case SCHED_IDLE: ret = 0; } return ret; } SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid, struct timespec __user *, interval) { struct task_struct *p; unsigned int time_slice; unsigned long flags; struct rq *rq; int retval; struct timespec t; if (pid < 0) return -EINVAL; retval = -ESRCH; rcu_read_lock(); p = find_process_by_pid(pid); if (!p) goto out_unlock; retval = security_task_getscheduler(p); if (retval) goto out_unlock; rq = task_rq_lock(p, &flags); time_slice = p->sched_class->get_rr_interval(rq, p); task_rq_unlock(rq, p, &flags); rcu_read_unlock(); jiffies_to_timespec(time_slice, &t); retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0; return retval; out_unlock: rcu_read_unlock(); return retval; } static const char stat_nam[] = TASK_STATE_TO_CHAR_STR; void sched_show_task(struct task_struct *p) { unsigned long free = 0; unsigned state; state = p->state ? __ffs(p->state) + 1 : 0; printk(KERN_INFO "%-15.15s %c", p->comm, state < sizeof(stat_nam) - 1 ? stat_nam[state] : '?'); #if BITS_PER_LONG == 32 if (state == TASK_RUNNING) printk(KERN_CONT " running "); else printk(KERN_CONT " %08lx ", thread_saved_pc(p)); #else if (state == TASK_RUNNING) printk(KERN_CONT " running task "); else printk(KERN_CONT " %016lx ", thread_saved_pc(p)); #endif #ifdef CONFIG_DEBUG_STACK_USAGE free = stack_not_used(p); #endif printk(KERN_CONT "%5lu %5d %6d 0x%08lx c%d %llu\n", free, task_pid_nr(p), task_pid_nr(rcu_dereference(p->real_parent)), (unsigned long)task_thread_info(p)->flags, p->on_cpu, #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) div64_u64(task_rq(p)->clock - p->sched_info.last_arrival, NSEC_PER_MSEC)); #else (unsigned long long)0); #endif #if defined(CONFIG_DEBUG_MUTEXES) if (state == TASK_UNINTERRUPTIBLE) if (p->blocked_by) printk(KERN_CONT " blocked by %s (%d) for %u ms\n", p->blocked_by->comm, p->blocked_by->tgid, jiffies_to_msecs(jiffies - p->blocked_since)); #endif show_stack(p, NULL); } void show_state_filter(unsigned long state_filter) { show_thread_group_state_filter(NULL, state_filter); } void show_thread_group_state_filter(const char *tg_comm, unsigned long state_filter) { struct task_struct *g, *p; #if BITS_PER_LONG == 32 printk(KERN_INFO " task PC stack pid father\n"); #else printk(KERN_INFO " task PC stack pid father\n"); #endif rcu_read_lock(); do_each_thread(g, p) { touch_nmi_watchdog(); if (!tg_comm || (tg_comm && !strncmp(tg_comm, g->comm, TASK_COMM_LEN))) { if (!state_filter || (p->state & state_filter)) sched_show_task(p); } } while_each_thread(g, p); touch_all_softlockup_watchdogs(); #ifdef CONFIG_SCHED_DEBUG sysrq_sched_debug_show(); #endif rcu_read_unlock(); if (!state_filter) debug_show_all_locks(); } void __cpuinit init_idle_bootup_task(struct task_struct *idle) { idle->sched_class = &idle_sched_class; } void __cpuinit init_idle(struct task_struct *idle, int cpu) { struct rq *rq = cpu_rq(cpu); unsigned long flags; raw_spin_lock_irqsave(&rq->lock, flags); __sched_fork(idle); idle->state = TASK_RUNNING; idle->se.exec_start = sched_clock(); do_set_cpus_allowed(idle, cpumask_of(cpu)); rcu_read_lock(); __set_task_cpu(idle, cpu); rcu_read_unlock(); rq->curr = rq->idle = idle; #if defined(CONFIG_SMP) idle->on_cpu = 1; #endif raw_spin_unlock_irqrestore(&rq->lock, flags); task_thread_info(idle)->preempt_count = 0; idle->sched_class = &idle_sched_class; ftrace_graph_init_idle_task(idle, cpu); #if defined(CONFIG_SMP) sprintf(idle->comm, "%s/%d", INIT_TASK_COMM, cpu); #endif } #ifdef CONFIG_SMP void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) { if (p->sched_class && p->sched_class->set_cpus_allowed) p->sched_class->set_cpus_allowed(p, new_mask); cpumask_copy(&p->cpus_allowed, new_mask); p->rt.nr_cpus_allowed = cpumask_weight(new_mask); } int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask) { unsigned long flags; struct rq *rq; unsigned int dest_cpu; int ret = 0; rq = task_rq_lock(p, &flags); if (cpumask_equal(&p->cpus_allowed, new_mask)) goto out; if (!cpumask_intersects(new_mask, cpu_active_mask)) { ret = -EINVAL; goto out; } if (unlikely((p->flags & PF_THREAD_BOUND) && p != current)) { ret = -EINVAL; goto out; } do_set_cpus_allowed(p, new_mask); if (cpumask_test_cpu(task_cpu(p), new_mask)) goto out; dest_cpu = cpumask_any_and(cpu_active_mask, new_mask); if (p->on_rq) { struct migration_arg arg = { p, dest_cpu }; task_rq_unlock(rq, p, &flags); stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg); tlb_migrate_finish(p->mm); return 0; } out: task_rq_unlock(rq, p, &flags); return ret; } EXPORT_SYMBOL_GPL(set_cpus_allowed_ptr); static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu) { struct rq *rq_dest, *rq_src; bool moved = false; int ret = 0; if (unlikely(!cpu_active(dest_cpu))) return ret; rq_src = cpu_rq(src_cpu); rq_dest = cpu_rq(dest_cpu); raw_spin_lock(&p->pi_lock); double_rq_lock(rq_src, rq_dest); if (task_cpu(p) != src_cpu) goto done; if (!cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p))) goto fail; if (p->on_rq) { dequeue_task(rq_src, p, 0); set_task_cpu(p, dest_cpu); enqueue_task(rq_dest, p, 0); check_preempt_curr(rq_dest, p, 0); moved = true; } done: ret = 1; fail: double_rq_unlock(rq_src, rq_dest); raw_spin_unlock(&p->pi_lock); if (moved && task_notify_on_migrate(p)) atomic_notifier_call_chain(&migration_notifier_head, dest_cpu, (void *)src_cpu); return ret; } static int migration_cpu_stop(void *data) { struct migration_arg *arg = data; local_irq_disable(); __migrate_task(arg->task, raw_smp_processor_id(), arg->dest_cpu); local_irq_enable(); return 0; } #ifdef CONFIG_HOTPLUG_CPU void idle_task_exit(void) { struct mm_struct *mm = current->active_mm; BUG_ON(cpu_online(smp_processor_id())); if (mm != &init_mm) switch_mm(mm, &init_mm, current); mmdrop(mm); } static void calc_load_migrate(struct rq *rq) { long delta = calc_load_fold_active(rq); if (delta) atomic_long_add(delta, &calc_load_tasks); } static void migrate_tasks(unsigned int dead_cpu) { struct rq *rq = cpu_rq(dead_cpu); struct task_struct *next, *stop = rq->stop; int dest_cpu; rq->stop = NULL; for ( ; ; ) { if (rq->nr_running == 1) break; next = pick_next_task(rq); BUG_ON(!next); next->sched_class->put_prev_task(rq, next); dest_cpu = select_fallback_rq(dead_cpu, next); raw_spin_unlock(&rq->lock); __migrate_task(next, dead_cpu, dest_cpu); raw_spin_lock(&rq->lock); } rq->stop = stop; } #endif #if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL) static struct ctl_table sd_ctl_dir[] = { { .procname = "sched_domain", .mode = 0555, }, {} }; static struct ctl_table sd_ctl_root[] = { { .procname = "kernel", .mode = 0555, .child = sd_ctl_dir, }, {} }; static struct ctl_table *sd_alloc_ctl_entry(int n) { struct ctl_table *entry = kcalloc(n, sizeof(struct ctl_table), GFP_KERNEL); return entry; } static void sd_free_ctl_entry(struct ctl_table **tablep) { struct ctl_table *entry; for (entry = *tablep; entry->mode; entry++) { if (entry->child) sd_free_ctl_entry(&entry->child); if (entry->proc_handler == NULL) kfree(entry->procname); } kfree(*tablep); *tablep = NULL; } static int min_load_idx = 0; static int max_load_idx = CPU_LOAD_IDX_MAX-1; static void set_table_entry(struct ctl_table *entry, const char *procname, void *data, int maxlen, umode_t mode, proc_handler *proc_handler, bool load_idx) { entry->procname = procname; entry->data = data; entry->maxlen = maxlen; entry->mode = mode; entry->proc_handler = proc_handler; if (load_idx) { entry->extra1 = &min_load_idx; entry->extra2 = &max_load_idx; } } static struct ctl_table * sd_alloc_ctl_domain_table(struct sched_domain *sd) { struct ctl_table *table = sd_alloc_ctl_entry(13); if (table == NULL) return NULL; set_table_entry(&table[0], "min_interval", &sd->min_interval, sizeof(long), 0644, proc_doulongvec_minmax, false); set_table_entry(&table[1], "max_interval", &sd->max_interval, sizeof(long), 0644, proc_doulongvec_minmax, false); set_table_entry(&table[2], "busy_idx", &sd->busy_idx, sizeof(int), 0644, proc_dointvec_minmax, true); set_table_entry(&table[3], "idle_idx", &sd->idle_idx, sizeof(int), 0644, proc_dointvec_minmax, true); set_table_entry(&table[4], "newidle_idx", &sd->newidle_idx, sizeof(int), 0644, proc_dointvec_minmax, true); set_table_entry(&table[5], "wake_idx", &sd->wake_idx, sizeof(int), 0644, proc_dointvec_minmax, true); set_table_entry(&table[6], "forkexec_idx", &sd->forkexec_idx, sizeof(int), 0644, proc_dointvec_minmax, true); set_table_entry(&table[7], "busy_factor", &sd->busy_factor, sizeof(int), 0644, proc_dointvec_minmax, false); set_table_entry(&table[8], "imbalance_pct", &sd->imbalance_pct, sizeof(int), 0644, proc_dointvec_minmax, false); set_table_entry(&table[9], "cache_nice_tries", &sd->cache_nice_tries, sizeof(int), 0644, proc_dointvec_minmax, false); set_table_entry(&table[10], "flags", &sd->flags, sizeof(int), 0644, proc_dointvec_minmax, false); set_table_entry(&table[11], "name", sd->name, CORENAME_MAX_SIZE, 0444, proc_dostring, false); /* &table[12] is terminator */ return table; } static ctl_table *sd_alloc_ctl_cpu_table(int cpu) { struct ctl_table *entry, *table; struct sched_domain *sd; int domain_num = 0, i; char buf[32]; for_each_domain(cpu, sd) domain_num++; entry = table = sd_alloc_ctl_entry(domain_num + 1); if (table == NULL) return NULL; i = 0; for_each_domain(cpu, sd) { snprintf(buf, 32, "domain%d", i); entry->procname = kstrdup(buf, GFP_KERNEL); entry->mode = 0555; entry->child = sd_alloc_ctl_domain_table(sd); entry++; i++; } return table; } static struct ctl_table_header *sd_sysctl_header; static void register_sched_domain_sysctl(void) { int i, cpu_num = num_possible_cpus(); struct ctl_table *entry = sd_alloc_ctl_entry(cpu_num + 1); char buf[32]; WARN_ON(sd_ctl_dir[0].child); sd_ctl_dir[0].child = entry; if (entry == NULL) return; for_each_possible_cpu(i) { snprintf(buf, 32, "cpu%d", i); entry->procname = kstrdup(buf, GFP_KERNEL); entry->mode = 0555; entry->child = sd_alloc_ctl_cpu_table(i); entry++; } WARN_ON(sd_sysctl_header); sd_sysctl_header = register_sysctl_table(sd_ctl_root); } static void unregister_sched_domain_sysctl(void) { if (sd_sysctl_header) unregister_sysctl_table(sd_sysctl_header); sd_sysctl_header = NULL; if (sd_ctl_dir[0].child) sd_free_ctl_entry(&sd_ctl_dir[0].child); } #else static void register_sched_domain_sysctl(void) { } static void unregister_sched_domain_sysctl(void) { } #endif static void set_rq_online(struct rq *rq) { if (!rq->online) { const struct sched_class *class; cpumask_set_cpu(rq->cpu, rq->rd->online); rq->online = 1; for_each_class(class) { if (class->rq_online) class->rq_online(rq); } } } static void set_rq_offline(struct rq *rq) { if (rq->online) { const struct sched_class *class; for_each_class(class) { if (class->rq_offline) class->rq_offline(rq); } cpumask_clear_cpu(rq->cpu, rq->rd->online); rq->online = 0; } } static int __cpuinit migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) { int cpu = (long)hcpu; unsigned long flags; struct rq *rq = cpu_rq(cpu); switch (action & ~CPU_TASKS_FROZEN) { case CPU_UP_PREPARE: rq->calc_load_update = calc_load_update; break; case CPU_ONLINE: raw_spin_lock_irqsave(&rq->lock, flags); if (rq->rd) { BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span)); set_rq_online(rq); } raw_spin_unlock_irqrestore(&rq->lock, flags); break; #ifdef CONFIG_HOTPLUG_CPU case CPU_DYING: sched_ttwu_pending(); raw_spin_lock_irqsave(&rq->lock, flags); if (rq->rd) { BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span)); set_rq_offline(rq); } migrate_tasks(cpu); BUG_ON(rq->nr_running != 1); raw_spin_unlock_irqrestore(&rq->lock, flags); break; case CPU_DEAD: calc_load_migrate(rq); break; #endif } update_max_interval(); return NOTIFY_OK; } static struct notifier_block __cpuinitdata migration_notifier = { .notifier_call = migration_call, .priority = CPU_PRI_MIGRATION, }; static int __cpuinit sched_cpu_active(struct notifier_block *nfb, unsigned long action, void *hcpu) { switch (action & ~CPU_TASKS_FROZEN) { case CPU_DOWN_FAILED: set_cpu_active((long)hcpu, true); return NOTIFY_OK; default: return NOTIFY_DONE; } } static int __cpuinit sched_cpu_inactive(struct notifier_block *nfb, unsigned long action, void *hcpu) { switch (action & ~CPU_TASKS_FROZEN) { case CPU_DOWN_PREPARE: set_cpu_active((long)hcpu, false); return NOTIFY_OK; default: return NOTIFY_DONE; } } static int __init migration_init(void) { void *cpu = (void *)(long)smp_processor_id(); int err; err = migration_call(&migration_notifier, CPU_UP_PREPARE, cpu); BUG_ON(err == NOTIFY_BAD); migration_call(&migration_notifier, CPU_ONLINE, cpu); register_cpu_notifier(&migration_notifier); cpu_notifier(sched_cpu_active, CPU_PRI_SCHED_ACTIVE); cpu_notifier(sched_cpu_inactive, CPU_PRI_SCHED_INACTIVE); return 0; } early_initcall(migration_init); #endif #ifdef CONFIG_SMP static cpumask_var_t sched_domains_tmpmask; #ifdef CONFIG_SCHED_DEBUG static __read_mostly int sched_domain_debug_enabled; static int __init sched_domain_debug_setup(char *str) { sched_domain_debug_enabled = 1; return 0; } early_param("sched_debug", sched_domain_debug_setup); static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level, struct cpumask *groupmask) { struct sched_group *group = sd->groups; char str[256]; cpulist_scnprintf(str, sizeof(str), sched_domain_span(sd)); cpumask_clear(groupmask); printk(KERN_DEBUG "%*s domain %d: ", level, "", level); if (!(sd->flags & SD_LOAD_BALANCE)) { printk("does not load-balance\n"); if (sd->parent) printk(KERN_ERR "ERROR: !SD_LOAD_BALANCE domain" " has parent"); return -1; } printk(KERN_CONT "span %s level %s\n", str, sd->name); if (!cpumask_test_cpu(cpu, sched_domain_span(sd))) { printk(KERN_ERR "ERROR: domain->span does not contain " "CPU%d\n", cpu); } if (!cpumask_test_cpu(cpu, sched_group_cpus(group))) { printk(KERN_ERR "ERROR: domain->groups does not contain" " CPU%d\n", cpu); } printk(KERN_DEBUG "%*s groups:", level + 1, ""); do { if (!group) { printk("\n"); printk(KERN_ERR "ERROR: group is NULL\n"); break; } if (!group->sgp->power) { printk(KERN_CONT "\n"); printk(KERN_ERR "ERROR: domain->cpu_power not " "set\n"); break; } if (!cpumask_weight(sched_group_cpus(group))) { printk(KERN_CONT "\n"); printk(KERN_ERR "ERROR: empty group\n"); break; } if (cpumask_intersects(groupmask, sched_group_cpus(group))) { printk(KERN_CONT "\n"); printk(KERN_ERR "ERROR: repeated CPUs\n"); break; } cpumask_or(groupmask, groupmask, sched_group_cpus(group)); cpulist_scnprintf(str, sizeof(str), sched_group_cpus(group)); printk(KERN_CONT " %s", str); if (group->sgp->power != SCHED_POWER_SCALE) { printk(KERN_CONT " (cpu_power = %d)", group->sgp->power); } group = group->next; } while (group != sd->groups); printk(KERN_CONT "\n"); if (!cpumask_equal(sched_domain_span(sd), groupmask)) printk(KERN_ERR "ERROR: groups don't span domain->span\n"); if (sd->parent && !cpumask_subset(groupmask, sched_domain_span(sd->parent))) printk(KERN_ERR "ERROR: parent span is not a superset " "of domain->span\n"); return 0; } static void sched_domain_debug(struct sched_domain *sd, int cpu) { int level = 0; if (!sched_domain_debug_enabled) return; if (!sd) { printk(KERN_DEBUG "CPU%d attaching NULL sched-domain.\n", cpu); return; } printk(KERN_DEBUG "CPU%d attaching sched-domain:\n", cpu); for (;;) { if (sched_domain_debug_one(sd, cpu, level, sched_domains_tmpmask)) break; level++; sd = sd->parent; if (!sd) break; } } #else # define sched_domain_debug(sd, cpu) do { } while (0) #endif static int sd_degenerate(struct sched_domain *sd) { if (cpumask_weight(sched_domain_span(sd)) == 1) return 1; if (sd->flags & (SD_LOAD_BALANCE | SD_BALANCE_NEWIDLE | SD_BALANCE_FORK | SD_BALANCE_EXEC | SD_SHARE_CPUPOWER | SD_SHARE_PKG_RESOURCES)) { if (sd->groups != sd->groups->next) return 0; } if (sd->flags & (SD_WAKE_AFFINE)) return 0; return 1; } static int sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent) { unsigned long cflags = sd->flags, pflags = parent->flags; if (sd_degenerate(parent)) return 1; if (!cpumask_equal(sched_domain_span(sd), sched_domain_span(parent))) return 0; if (parent->groups == parent->groups->next) { pflags &= ~(SD_LOAD_BALANCE | SD_BALANCE_NEWIDLE | SD_BALANCE_FORK | SD_BALANCE_EXEC | SD_SHARE_CPUPOWER | SD_SHARE_PKG_RESOURCES); if (nr_node_ids == 1) pflags &= ~SD_SERIALIZE; } if (~cflags & pflags) return 0; return 1; } static void free_rootdomain(struct rcu_head *rcu) { struct root_domain *rd = container_of(rcu, struct root_domain, rcu); cpupri_cleanup(&rd->cpupri); free_cpumask_var(rd->rto_mask); free_cpumask_var(rd->online); free_cpumask_var(rd->span); kfree(rd); } static void rq_attach_root(struct rq *rq, struct root_domain *rd) { struct root_domain *old_rd = NULL; unsigned long flags; raw_spin_lock_irqsave(&rq->lock, flags); if (rq->rd) { old_rd = rq->rd; if (cpumask_test_cpu(rq->cpu, old_rd->online)) set_rq_offline(rq); cpumask_clear_cpu(rq->cpu, old_rd->span); if (!atomic_dec_and_test(&old_rd->refcount)) old_rd = NULL; } atomic_inc(&rd->refcount); rq->rd = rd; cpumask_set_cpu(rq->cpu, rd->span); if (cpumask_test_cpu(rq->cpu, cpu_active_mask)) set_rq_online(rq); raw_spin_unlock_irqrestore(&rq->lock, flags); if (old_rd) call_rcu_sched(&old_rd->rcu, free_rootdomain); } static int init_rootdomain(struct root_domain *rd) { memset(rd, 0, sizeof(*rd)); if (!alloc_cpumask_var(&rd->span, GFP_KERNEL)) goto out; if (!alloc_cpumask_var(&rd->online, GFP_KERNEL)) goto free_span; if (!alloc_cpumask_var(&rd->rto_mask, GFP_KERNEL)) goto free_online; if (cpupri_init(&rd->cpupri) != 0) goto free_rto_mask; return 0; free_rto_mask: free_cpumask_var(rd->rto_mask); free_online: free_cpumask_var(rd->online); free_span: free_cpumask_var(rd->span); out: return -ENOMEM; } struct root_domain def_root_domain; static void init_defrootdomain(void) { init_rootdomain(&def_root_domain); atomic_set(&def_root_domain.refcount, 1); } static struct root_domain *alloc_rootdomain(void) { struct root_domain *rd; rd = kmalloc(sizeof(*rd), GFP_KERNEL); if (!rd) return NULL; if (init_rootdomain(rd) != 0) { kfree(rd); return NULL; } return rd; } static void free_sched_groups(struct sched_group *sg, int free_sgp) { struct sched_group *tmp, *first; if (!sg) return; first = sg; do { tmp = sg->next; if (free_sgp && atomic_dec_and_test(&sg->sgp->ref)) kfree(sg->sgp); kfree(sg); sg = tmp; } while (sg != first); } static void free_sched_domain(struct rcu_head *rcu) { struct sched_domain *sd = container_of(rcu, struct sched_domain, rcu); if (sd->flags & SD_OVERLAP) { free_sched_groups(sd->groups, 1); } else if (atomic_dec_and_test(&sd->groups->ref)) { kfree(sd->groups->sgp); kfree(sd->groups); } kfree(sd); } static void destroy_sched_domain(struct sched_domain *sd, int cpu) { call_rcu(&sd->rcu, free_sched_domain); } static void destroy_sched_domains(struct sched_domain *sd, int cpu) { for (; sd; sd = sd->parent) destroy_sched_domain(sd, cpu); } DEFINE_PER_CPU(struct sched_domain *, sd_llc); DEFINE_PER_CPU(int, sd_llc_id); static void update_top_cache_domain(int cpu) { struct sched_domain *sd; int id = cpu; sd = highest_flag_domain(cpu, SD_SHARE_PKG_RESOURCES); if (sd) id = cpumask_first(sched_domain_span(sd)); rcu_assign_pointer(per_cpu(sd_llc, cpu), sd); per_cpu(sd_llc_id, cpu) = id; } static void cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) { struct rq *rq = cpu_rq(cpu); struct sched_domain *tmp; unsigned long next_balance = rq->next_balance; for (tmp = sd; tmp; ) { struct sched_domain *parent = tmp->parent; if (!parent) break; if (sd_parent_degenerate(tmp, parent)) { tmp->parent = parent->parent; if (parent->parent) parent->parent->child = tmp; destroy_sched_domain(parent, cpu); } else tmp = tmp->parent; } if (sd && sd_degenerate(sd)) { tmp = sd; sd = sd->parent; destroy_sched_domain(tmp, cpu); if (sd) sd->child = NULL; } for (tmp = sd; tmp; ) { unsigned long interval; interval = msecs_to_jiffies(tmp->balance_interval); if (time_after(next_balance, tmp->last_balance + interval)) next_balance = tmp->last_balance + interval; tmp = tmp->parent; } rq->next_balance = next_balance; sched_domain_debug(sd, cpu); rq_attach_root(rq, rd); tmp = rq->sd; rcu_assign_pointer(rq->sd, sd); destroy_sched_domains(tmp, cpu); update_top_cache_domain(cpu); } static cpumask_var_t cpu_isolated_map; static int __init isolated_cpu_setup(char *str) { alloc_bootmem_cpumask_var(&cpu_isolated_map); cpulist_parse(str, cpu_isolated_map); return 1; } __setup("isolcpus=", isolated_cpu_setup); #ifdef CONFIG_NUMA static int find_next_best_node(int node, nodemask_t *used_nodes) { int i, n, val, min_val, best_node = -1; min_val = INT_MAX; for (i = 0; i < nr_node_ids; i++) { n = (node + i) % nr_node_ids; if (!nr_cpus_node(n)) continue; if (node_isset(n, *used_nodes)) continue; val = node_distance(node, n); if (val < min_val) { min_val = val; best_node = n; } } if (best_node != -1) node_set(best_node, *used_nodes); return best_node; } static void sched_domain_node_span(int node, struct cpumask *span) { nodemask_t used_nodes; int i; cpumask_clear(span); nodes_clear(used_nodes); cpumask_or(span, span, cpumask_of_node(node)); node_set(node, used_nodes); for (i = 1; i < SD_NODES_PER_DOMAIN; i++) { int next_node = find_next_best_node(node, &used_nodes); if (next_node < 0) break; cpumask_or(span, span, cpumask_of_node(next_node)); } } static const struct cpumask *cpu_node_mask(int cpu) { lockdep_assert_held(&sched_domains_mutex); sched_domain_node_span(cpu_to_node(cpu), sched_domains_tmpmask); return sched_domains_tmpmask; } static const struct cpumask *cpu_allnodes_mask(int cpu) { return cpu_possible_mask; } #endif static const struct cpumask *cpu_cpu_mask(int cpu) { return cpumask_of_node(cpu_to_node(cpu)); } int sched_smt_power_savings = 0, sched_mc_power_savings = 0; struct sd_data { struct sched_domain **__percpu sd; struct sched_group **__percpu sg; struct sched_group_power **__percpu sgp; }; struct s_data { struct sched_domain ** __percpu sd; struct root_domain *rd; }; enum s_alloc { sa_rootdomain, sa_sd, sa_sd_storage, sa_none, }; struct sched_domain_topology_level; typedef struct sched_domain *(*sched_domain_init_f)(struct sched_domain_topology_level *tl, int cpu); typedef const struct cpumask *(*sched_domain_mask_f)(int cpu); #define SDTL_OVERLAP 0x01 struct sched_domain_topology_level { sched_domain_init_f init; sched_domain_mask_f mask; int flags; struct sd_data data; }; static int build_overlap_sched_groups(struct sched_domain *sd, int cpu) { struct sched_group *first = NULL, *last = NULL, *groups = NULL, *sg; const struct cpumask *span = sched_domain_span(sd); struct cpumask *covered = sched_domains_tmpmask; struct sd_data *sdd = sd->private; struct sched_domain *child; int i; cpumask_clear(covered); for_each_cpu(i, span) { struct cpumask *sg_span; if (cpumask_test_cpu(i, covered)) continue; sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(), GFP_KERNEL, cpu_to_node(cpu)); if (!sg) goto fail; sg_span = sched_group_cpus(sg); child = *per_cpu_ptr(sdd->sd, i); if (child->child) { child = child->child; cpumask_copy(sg_span, sched_domain_span(child)); } else cpumask_set_cpu(i, sg_span); cpumask_or(covered, covered, sg_span); sg->sgp = *per_cpu_ptr(sdd->sgp, cpumask_first(sg_span)); atomic_inc(&sg->sgp->ref); if (cpumask_test_cpu(cpu, sg_span)) groups = sg; if (!first) first = sg; if (last) last->next = sg; last = sg; last->next = first; } sd->groups = groups; return 0; fail: free_sched_groups(first, 0); return -ENOMEM; } static int get_group(int cpu, struct sd_data *sdd, struct sched_group **sg) { struct sched_domain *sd = *per_cpu_ptr(sdd->sd, cpu); struct sched_domain *child = sd->child; if (child) cpu = cpumask_first(sched_domain_span(child)); if (sg) { *sg = *per_cpu_ptr(sdd->sg, cpu); (*sg)->sgp = *per_cpu_ptr(sdd->sgp, cpu); atomic_set(&(*sg)->sgp->ref, 1); } return cpu; } static int build_sched_groups(struct sched_domain *sd, int cpu) { struct sched_group *first = NULL, *last = NULL; struct sd_data *sdd = sd->private; const struct cpumask *span = sched_domain_span(sd); struct cpumask *covered; int i; get_group(cpu, sdd, &sd->groups); atomic_inc(&sd->groups->ref); if (cpu != cpumask_first(sched_domain_span(sd))) return 0; lockdep_assert_held(&sched_domains_mutex); covered = sched_domains_tmpmask; cpumask_clear(covered); for_each_cpu(i, span) { struct sched_group *sg; int group = get_group(i, sdd, &sg); int j; if (cpumask_test_cpu(i, covered)) continue; cpumask_clear(sched_group_cpus(sg)); sg->sgp->power = 0; for_each_cpu(j, span) { if (get_group(j, sdd, NULL) != group) continue; cpumask_set_cpu(j, covered); cpumask_set_cpu(j, sched_group_cpus(sg)); } if (!first) first = sg; if (last) last->next = sg; last = sg; } if (last) last->next = first; return 0; } static void init_sched_groups_power(int cpu, struct sched_domain *sd) { struct sched_group *sg; BUG_ON(!sd); sg = sd->groups; BUG_ON(!sg); do { sg->group_weight = cpumask_weight(sched_group_cpus(sg)); sg = sg->next; } while (sg != sd->groups); if (cpu != group_first_cpu(sg)) return; update_group_power(sd, cpu); atomic_set(&sg->sgp->nr_busy_cpus, sg->group_weight); } int __weak arch_sd_sibling_asym_packing(void) { return 0*SD_ASYM_PACKING; } #ifdef CONFIG_SCHED_DEBUG # define SD_INIT_NAME(sd, type) sd->name = #type #else # define SD_INIT_NAME(sd, type) do { } while (0) #endif #define SD_INIT_FUNC(type) \ static noinline struct sched_domain * \ sd_init_##type(struct sched_domain_topology_level *tl, int cpu) \ { \ struct sched_domain *sd = *per_cpu_ptr(tl->data.sd, cpu); \ *sd = SD_##type##_INIT; \ SD_INIT_NAME(sd, type); \ sd->private = &tl->data; \ return sd; \ } SD_INIT_FUNC(CPU) #ifdef CONFIG_NUMA SD_INIT_FUNC(ALLNODES) SD_INIT_FUNC(NODE) #endif #ifdef CONFIG_SCHED_SMT SD_INIT_FUNC(SIBLING) #endif #ifdef CONFIG_SCHED_MC SD_INIT_FUNC(MC) #endif #ifdef CONFIG_SCHED_BOOK SD_INIT_FUNC(BOOK) #endif static int default_relax_domain_level = -1; int sched_domain_level_max; static int __init setup_relax_domain_level(char *str) { if (kstrtoint(str, 0, &default_relax_domain_level)) pr_warn("Unable to set relax_domain_level\n"); return 1; } __setup("relax_domain_level=", setup_relax_domain_level); static void set_domain_attribute(struct sched_domain *sd, struct sched_domain_attr *attr) { int request; if (!attr || attr->relax_domain_level < 0) { if (default_relax_domain_level < 0) return; else request = default_relax_domain_level; } else request = attr->relax_domain_level; if (request < sd->level) { sd->flags &= ~(SD_BALANCE_WAKE|SD_BALANCE_NEWIDLE); } else { sd->flags |= (SD_BALANCE_WAKE|SD_BALANCE_NEWIDLE); } } static void __sdt_free(const struct cpumask *cpu_map); static int __sdt_alloc(const struct cpumask *cpu_map); static void __free_domain_allocs(struct s_data *d, enum s_alloc what, const struct cpumask *cpu_map) { switch (what) { case sa_rootdomain: if (!atomic_read(&d->rd->refcount)) free_rootdomain(&d->rd->rcu); case sa_sd: free_percpu(d->sd); case sa_sd_storage: __sdt_free(cpu_map); case sa_none: break; } } static enum s_alloc __visit_domain_allocation_hell(struct s_data *d, const struct cpumask *cpu_map) { memset(d, 0, sizeof(*d)); if (__sdt_alloc(cpu_map)) return sa_sd_storage; d->sd = alloc_percpu(struct sched_domain *); if (!d->sd) return sa_sd_storage; d->rd = alloc_rootdomain(); if (!d->rd) return sa_sd; return sa_rootdomain; } static void claim_allocations(int cpu, struct sched_domain *sd) { struct sd_data *sdd = sd->private; WARN_ON_ONCE(*per_cpu_ptr(sdd->sd, cpu) != sd); *per_cpu_ptr(sdd->sd, cpu) = NULL; if (atomic_read(&(*per_cpu_ptr(sdd->sg, cpu))->ref)) *per_cpu_ptr(sdd->sg, cpu) = NULL; if (atomic_read(&(*per_cpu_ptr(sdd->sgp, cpu))->ref)) *per_cpu_ptr(sdd->sgp, cpu) = NULL; } #ifdef CONFIG_SCHED_SMT static const struct cpumask *cpu_smt_mask(int cpu) { return topology_thread_cpumask(cpu); } #endif static struct sched_domain_topology_level default_topology[] = { #ifdef CONFIG_SCHED_SMT { sd_init_SIBLING, cpu_smt_mask, }, #endif #ifdef CONFIG_SCHED_MC { sd_init_MC, cpu_coregroup_mask, }, #endif #ifdef CONFIG_SCHED_BOOK { sd_init_BOOK, cpu_book_mask, }, #endif { sd_init_CPU, cpu_cpu_mask, }, #ifdef CONFIG_NUMA { sd_init_NODE, cpu_node_mask, SDTL_OVERLAP, }, { sd_init_ALLNODES, cpu_allnodes_mask, }, #endif { NULL, }, }; static struct sched_domain_topology_level *sched_domain_topology = default_topology; static int __sdt_alloc(const struct cpumask *cpu_map) { struct sched_domain_topology_level *tl; int j; for (tl = sched_domain_topology; tl->init; tl++) { struct sd_data *sdd = &tl->data; sdd->sd = alloc_percpu(struct sched_domain *); if (!sdd->sd) return -ENOMEM; sdd->sg = alloc_percpu(struct sched_group *); if (!sdd->sg) return -ENOMEM; sdd->sgp = alloc_percpu(struct sched_group_power *); if (!sdd->sgp) return -ENOMEM; for_each_cpu(j, cpu_map) { struct sched_domain *sd; struct sched_group *sg; struct sched_group_power *sgp; sd = kzalloc_node(sizeof(struct sched_domain) + cpumask_size(), GFP_KERNEL, cpu_to_node(j)); if (!sd) return -ENOMEM; *per_cpu_ptr(sdd->sd, j) = sd; sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(), GFP_KERNEL, cpu_to_node(j)); if (!sg) return -ENOMEM; sg->next = sg; *per_cpu_ptr(sdd->sg, j) = sg; sgp = kzalloc_node(sizeof(struct sched_group_power), GFP_KERNEL, cpu_to_node(j)); if (!sgp) return -ENOMEM; *per_cpu_ptr(sdd->sgp, j) = sgp; } } return 0; } static void __sdt_free(const struct cpumask *cpu_map) { struct sched_domain_topology_level *tl; int j; for (tl = sched_domain_topology; tl->init; tl++) { struct sd_data *sdd = &tl->data; for_each_cpu(j, cpu_map) { struct sched_domain *sd; if (sdd->sd) { sd = *per_cpu_ptr(sdd->sd, j); if (sd && (sd->flags & SD_OVERLAP)) free_sched_groups(sd->groups, 0); kfree(*per_cpu_ptr(sdd->sd, j)); } if (sdd->sg) kfree(*per_cpu_ptr(sdd->sg, j)); if (sdd->sgp) kfree(*per_cpu_ptr(sdd->sgp, j)); } free_percpu(sdd->sd); sdd->sd = NULL; free_percpu(sdd->sg); sdd->sg = NULL; free_percpu(sdd->sgp); sdd->sgp = NULL; } } struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl, struct s_data *d, const struct cpumask *cpu_map, struct sched_domain_attr *attr, struct sched_domain *child, int cpu) { struct sched_domain *sd = tl->init(tl, cpu); if (!sd) return child; cpumask_and(sched_domain_span(sd), cpu_map, tl->mask(cpu)); if (child) { sd->level = child->level + 1; sched_domain_level_max = max(sched_domain_level_max, sd->level); child->parent = sd; } sd->child = child; set_domain_attribute(sd, attr); return sd; } static int build_sched_domains(const struct cpumask *cpu_map, struct sched_domain_attr *attr) { enum s_alloc alloc_state = sa_none; struct sched_domain *sd; struct s_data d; int i, ret = -ENOMEM; alloc_state = __visit_domain_allocation_hell(&d, cpu_map); if (alloc_state != sa_rootdomain) goto error; for_each_cpu(i, cpu_map) { struct sched_domain_topology_level *tl; sd = NULL; for (tl = sched_domain_topology; tl->init; tl++) { sd = build_sched_domain(tl, &d, cpu_map, attr, sd, i); if (tl->flags & SDTL_OVERLAP || sched_feat(FORCE_SD_OVERLAP)) sd->flags |= SD_OVERLAP; if (cpumask_equal(cpu_map, sched_domain_span(sd))) break; } while (sd->child) sd = sd->child; *per_cpu_ptr(d.sd, i) = sd; } for_each_cpu(i, cpu_map) { for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) { sd->span_weight = cpumask_weight(sched_domain_span(sd)); if (sd->flags & SD_OVERLAP) { if (build_overlap_sched_groups(sd, i)) goto error; } else { if (build_sched_groups(sd, i)) goto error; } } } for (i = nr_cpumask_bits-1; i >= 0; i--) { if (!cpumask_test_cpu(i, cpu_map)) continue; for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) { claim_allocations(i, sd); init_sched_groups_power(i, sd); } } rcu_read_lock(); for_each_cpu(i, cpu_map) { sd = *per_cpu_ptr(d.sd, i); cpu_attach_domain(sd, d.rd, i); } rcu_read_unlock(); ret = 0; error: __free_domain_allocs(&d, alloc_state, cpu_map); return ret; } static cpumask_var_t *doms_cur; static int ndoms_cur; static struct sched_domain_attr *dattr_cur; static cpumask_var_t fallback_doms; int __attribute__((weak)) arch_update_cpu_topology(void) { return 0; } cpumask_var_t *alloc_sched_domains(unsigned int ndoms) { int i; cpumask_var_t *doms; doms = kmalloc(sizeof(*doms) * ndoms, GFP_KERNEL); if (!doms) return NULL; for (i = 0; i < ndoms; i++) { if (!alloc_cpumask_var(&doms[i], GFP_KERNEL)) { free_sched_domains(doms, i); return NULL; } } return doms; } void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms) { unsigned int i; for (i = 0; i < ndoms; i++) free_cpumask_var(doms[i]); kfree(doms); } static int init_sched_domains(const struct cpumask *cpu_map) { int err; arch_update_cpu_topology(); ndoms_cur = 1; doms_cur = alloc_sched_domains(ndoms_cur); if (!doms_cur) doms_cur = &fallback_doms; cpumask_andnot(doms_cur[0], cpu_map, cpu_isolated_map); dattr_cur = NULL; err = build_sched_domains(doms_cur[0], NULL); register_sched_domain_sysctl(); return err; } static void detach_destroy_domains(const struct cpumask *cpu_map) { int i; rcu_read_lock(); for_each_cpu(i, cpu_map) cpu_attach_domain(NULL, &def_root_domain, i); rcu_read_unlock(); } static int dattrs_equal(struct sched_domain_attr *cur, int idx_cur, struct sched_domain_attr *new, int idx_new) { struct sched_domain_attr tmp; if (!new && !cur) return 1; tmp = SD_ATTR_INIT; return !memcmp(cur ? (cur + idx_cur) : &tmp, new ? (new + idx_new) : &tmp, sizeof(struct sched_domain_attr)); } void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], struct sched_domain_attr *dattr_new) { int i, j, n; int new_topology; mutex_lock(&sched_domains_mutex); unregister_sched_domain_sysctl(); new_topology = arch_update_cpu_topology(); n = doms_new ? ndoms_new : 0; for (i = 0; i < ndoms_cur; i++) { for (j = 0; j < n && !new_topology; j++) { if (cpumask_equal(doms_cur[i], doms_new[j]) && dattrs_equal(dattr_cur, i, dattr_new, j)) goto match1; } detach_destroy_domains(doms_cur[i]); match1: ; } if (doms_new == NULL) { ndoms_cur = 0; doms_new = &fallback_doms; cpumask_andnot(doms_new[0], cpu_active_mask, cpu_isolated_map); WARN_ON_ONCE(dattr_new); } for (i = 0; i < ndoms_new; i++) { for (j = 0; j < ndoms_cur && !new_topology; j++) { if (cpumask_equal(doms_new[i], doms_cur[j]) && dattrs_equal(dattr_new, i, dattr_cur, j)) goto match2; } build_sched_domains(doms_new[i], dattr_new ? dattr_new + i : NULL); match2: ; } if (doms_cur != &fallback_doms) free_sched_domains(doms_cur, ndoms_cur); kfree(dattr_cur); doms_cur = doms_new; dattr_cur = dattr_new; ndoms_cur = ndoms_new; register_sched_domain_sysctl(); mutex_unlock(&sched_domains_mutex); } #if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT) static void reinit_sched_domains(void) { get_online_cpus(); partition_sched_domains(0, NULL, NULL); rebuild_sched_domains(); put_online_cpus(); } static ssize_t sched_power_savings_store(const char *buf, size_t count, int smt) { unsigned int level = 0; if (sscanf(buf, "%u", &level) != 1) return -EINVAL; if (level >= MAX_POWERSAVINGS_BALANCE_LEVELS) return -EINVAL; if (smt) sched_smt_power_savings = level; else sched_mc_power_savings = level; reinit_sched_domains(); return count; } #ifdef CONFIG_SCHED_MC static ssize_t sched_mc_power_savings_show(struct device *dev, struct device_attribute *attr, char *buf) { return sprintf(buf, "%u\n", sched_mc_power_savings); } static ssize_t sched_mc_power_savings_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { return sched_power_savings_store(buf, count, 0); } static DEVICE_ATTR(sched_mc_power_savings, 0644, sched_mc_power_savings_show, sched_mc_power_savings_store); #endif #ifdef CONFIG_SCHED_SMT static ssize_t sched_smt_power_savings_show(struct device *dev, struct device_attribute *attr, char *buf) { return sprintf(buf, "%u\n", sched_smt_power_savings); } static ssize_t sched_smt_power_savings_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { return sched_power_savings_store(buf, count, 1); } static DEVICE_ATTR(sched_smt_power_savings, 0644, sched_smt_power_savings_show, sched_smt_power_savings_store); #endif int __init sched_create_sysfs_power_savings_entries(struct device *dev) { int err = 0; #ifdef CONFIG_SCHED_SMT if (smt_capable()) err = device_create_file(dev, &dev_attr_sched_smt_power_savings); #endif #ifdef CONFIG_SCHED_MC if (!err && mc_capable()) err = device_create_file(dev, &dev_attr_sched_mc_power_savings); #endif return err; } #endif static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action, void *hcpu) { switch (action & ~CPU_TASKS_FROZEN) { case CPU_ONLINE: case CPU_DOWN_FAILED: cpuset_update_active_cpus(); return NOTIFY_OK; default: return NOTIFY_DONE; } } static int cpuset_cpu_inactive(struct notifier_block *nfb, unsigned long action, void *hcpu) { switch (action & ~CPU_TASKS_FROZEN) { case CPU_DOWN_PREPARE: cpuset_update_active_cpus(); return NOTIFY_OK; default: return NOTIFY_DONE; } } void __init sched_init_smp(void) { cpumask_var_t non_isolated_cpus; alloc_cpumask_var(&non_isolated_cpus, GFP_KERNEL); alloc_cpumask_var(&fallback_doms, GFP_KERNEL); get_online_cpus(); mutex_lock(&sched_domains_mutex); init_sched_domains(cpu_active_mask); cpumask_andnot(non_isolated_cpus, cpu_possible_mask, cpu_isolated_map); if (cpumask_empty(non_isolated_cpus)) cpumask_set_cpu(smp_processor_id(), non_isolated_cpus); mutex_unlock(&sched_domains_mutex); put_online_cpus(); hotcpu_notifier(cpuset_cpu_active, CPU_PRI_CPUSET_ACTIVE); hotcpu_notifier(cpuset_cpu_inactive, CPU_PRI_CPUSET_INACTIVE); hotcpu_notifier(update_runtime, 0); init_hrtick(); if (set_cpus_allowed_ptr(current, non_isolated_cpus) < 0) BUG(); sched_init_granularity(); free_cpumask_var(non_isolated_cpus); init_sched_rt_class(); } #else void __init sched_init_smp(void) { sched_init_granularity(); } #endif const_debug unsigned int sysctl_timer_migration = 1; int in_sched_functions(unsigned long addr) { return in_lock_functions(addr) || (addr >= (unsigned long)__sched_text_start && addr < (unsigned long)__sched_text_end); } #ifdef CONFIG_CGROUP_SCHED struct task_group root_task_group; #endif DECLARE_PER_CPU(cpumask_var_t, load_balance_tmpmask); void __init sched_init(void) { int i, j; unsigned long alloc_size = 0, ptr; #ifdef CONFIG_FAIR_GROUP_SCHED alloc_size += 2 * nr_cpu_ids * sizeof(void **); #endif #ifdef CONFIG_RT_GROUP_SCHED alloc_size += 2 * nr_cpu_ids * sizeof(void **); #endif #ifdef CONFIG_CPUMASK_OFFSTACK alloc_size += num_possible_cpus() * cpumask_size(); #endif if (alloc_size) { ptr = (unsigned long)kzalloc(alloc_size, GFP_NOWAIT); #ifdef CONFIG_FAIR_GROUP_SCHED root_task_group.se = (struct sched_entity **)ptr; ptr += nr_cpu_ids * sizeof(void **); root_task_group.cfs_rq = (struct cfs_rq **)ptr; ptr += nr_cpu_ids * sizeof(void **); #endif #ifdef CONFIG_RT_GROUP_SCHED root_task_group.rt_se = (struct sched_rt_entity **)ptr; ptr += nr_cpu_ids * sizeof(void **); root_task_group.rt_rq = (struct rt_rq **)ptr; ptr += nr_cpu_ids * sizeof(void **); #endif #ifdef CONFIG_CPUMASK_OFFSTACK for_each_possible_cpu(i) { per_cpu(load_balance_tmpmask, i) = (void *)ptr; ptr += cpumask_size(); } #endif } #ifdef CONFIG_SMP init_defrootdomain(); #endif init_rt_bandwidth(&def_rt_bandwidth, global_rt_period(), global_rt_runtime()); #ifdef CONFIG_RT_GROUP_SCHED init_rt_bandwidth(&root_task_group.rt_bandwidth, global_rt_period(), global_rt_runtime()); #endif #ifdef CONFIG_CGROUP_SCHED list_add(&root_task_group.list, &task_groups); INIT_LIST_HEAD(&root_task_group.children); INIT_LIST_HEAD(&root_task_group.siblings); autogroup_init(&init_task); #endif #ifdef CONFIG_CGROUP_CPUACCT root_cpuacct.cpustat = &kernel_cpustat; root_cpuacct.cpuusage = alloc_percpu(u64); BUG_ON(!root_cpuacct.cpuusage); #endif for_each_possible_cpu(i) { struct rq *rq; rq = cpu_rq(i); raw_spin_lock_init(&rq->lock); rq->nr_running = 0; rq->calc_load_active = 0; rq->calc_load_update = jiffies + LOAD_FREQ; init_cfs_rq(&rq->cfs); init_rt_rq(&rq->rt, rq); #ifdef CONFIG_FAIR_GROUP_SCHED root_task_group.shares = ROOT_TASK_GROUP_LOAD; INIT_LIST_HEAD(&rq->leaf_cfs_rq_list); init_cfs_bandwidth(&root_task_group.cfs_bandwidth); init_tg_cfs_entry(&root_task_group, &rq->cfs, NULL, i, NULL); #endif rq->rt.rt_runtime = def_rt_bandwidth.rt_runtime; #ifdef CONFIG_RT_GROUP_SCHED INIT_LIST_HEAD(&rq->leaf_rt_rq_list); init_tg_rt_entry(&root_task_group, &rq->rt, NULL, i, NULL); #endif for (j = 0; j < CPU_LOAD_IDX_MAX; j++) rq->cpu_load[j] = 0; rq->last_load_update_tick = jiffies; #ifdef CONFIG_SMP rq->sd = NULL; rq->rd = NULL; rq->cpu_power = SCHED_POWER_SCALE; rq->post_schedule = 0; rq->active_balance = 0; rq->next_balance = jiffies; rq->push_cpu = 0; rq->cpu = i; rq->online = 0; rq->idle_stamp = 0; rq->avg_idle = 2*sysctl_sched_migration_cost; INIT_LIST_HEAD(&rq->cfs_tasks); rq_attach_root(rq, &def_root_domain); #ifdef CONFIG_NO_HZ rq->nohz_flags = 0; #endif #endif init_rq_hrtick(rq); atomic_set(&rq->nr_iowait, 0); } set_load_weight(&init_task); #ifdef CONFIG_PREEMPT_NOTIFIERS INIT_HLIST_HEAD(&init_task.preempt_notifiers); #endif #ifdef CONFIG_RT_MUTEXES plist_head_init(&init_task.pi_waiters); #endif atomic_inc(&init_mm.mm_count); enter_lazy_tlb(&init_mm, current); init_idle(current, smp_processor_id()); calc_load_update = jiffies + LOAD_FREQ; current->sched_class = &fair_sched_class; #ifdef CONFIG_SMP zalloc_cpumask_var(&sched_domains_tmpmask, GFP_NOWAIT); if (cpu_isolated_map == NULL) zalloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT); #endif init_sched_fair_class(); scheduler_running = 1; } #ifdef CONFIG_DEBUG_ATOMIC_SLEEP static inline int preempt_count_equals(int preempt_offset) { int nested = (preempt_count() & ~PREEMPT_ACTIVE) + rcu_preempt_depth(); return (nested == preempt_offset); } static int __might_sleep_init_called; int __init __might_sleep_init(void) { __might_sleep_init_called = 1; return 0; } early_initcall(__might_sleep_init); void __might_sleep(const char *file, int line, int preempt_offset) { static unsigned long prev_jiffy; rcu_sleep_check(); if ((preempt_count_equals(preempt_offset) && !irqs_disabled()) || oops_in_progress) return; if (system_state != SYSTEM_RUNNING && (!__might_sleep_init_called || system_state != SYSTEM_BOOTING)) return; if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy) return; prev_jiffy = jiffies; printk(KERN_ERR "BUG: sleeping function called from invalid context at %s:%d\n", file, line); printk(KERN_ERR "in_atomic(): %d, irqs_disabled(): %d, pid: %d, name: %s\n", in_atomic(), irqs_disabled(), current->pid, current->comm); debug_show_held_locks(current); if (irqs_disabled()) print_irqtrace_events(current); dump_stack(); } EXPORT_SYMBOL(__might_sleep); #endif #ifdef CONFIG_MAGIC_SYSRQ static void normalize_task(struct rq *rq, struct task_struct *p) { const struct sched_class *prev_class = p->sched_class; int old_prio = p->prio; int on_rq; on_rq = p->on_rq; if (on_rq) dequeue_task(rq, p, 0); __setscheduler(rq, p, SCHED_NORMAL, 0); if (on_rq) { enqueue_task(rq, p, 0); resched_task(rq->curr); } check_class_changed(rq, p, prev_class, old_prio); } void normalize_rt_tasks(void) { struct task_struct *g, *p; unsigned long flags; struct rq *rq; read_lock_irqsave(&tasklist_lock, flags); do_each_thread(g, p) { if (!p->mm) continue; p->se.exec_start = 0; #ifdef CONFIG_SCHEDSTATS p->se.statistics.wait_start = 0; p->se.statistics.sleep_start = 0; p->se.statistics.block_start = 0; #endif if (!rt_task(p)) { if (TASK_NICE(p) < 0 && p->mm) set_user_nice(p, 0); continue; } raw_spin_lock(&p->pi_lock); rq = __task_rq_lock(p); normalize_task(rq, p); __task_rq_unlock(rq); raw_spin_unlock(&p->pi_lock); } while_each_thread(g, p); read_unlock_irqrestore(&tasklist_lock, flags); } #endif #if defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB) struct task_struct *curr_task(int cpu) { return cpu_curr(cpu); } #endif #ifdef CONFIG_IA64 void set_curr_task(int cpu, struct task_struct *p) { cpu_curr(cpu) = p; } #endif #ifdef CONFIG_CGROUP_SCHED static DEFINE_SPINLOCK(task_group_lock); static void free_sched_group(struct task_group *tg) { free_fair_sched_group(tg); free_rt_sched_group(tg); autogroup_free(tg); kfree(tg); } struct task_group *sched_create_group(struct task_group *parent) { struct task_group *tg; unsigned long flags; tg = kzalloc(sizeof(*tg), GFP_KERNEL); if (!tg) return ERR_PTR(-ENOMEM); if (!alloc_fair_sched_group(tg, parent)) goto err; if (!alloc_rt_sched_group(tg, parent)) goto err; spin_lock_irqsave(&task_group_lock, flags); list_add_rcu(&tg->list, &task_groups); WARN_ON(!parent); tg->parent = parent; INIT_LIST_HEAD(&tg->children); list_add_rcu(&tg->siblings, &parent->children); spin_unlock_irqrestore(&task_group_lock, flags); return tg; err: free_sched_group(tg); return ERR_PTR(-ENOMEM); } static void free_sched_group_rcu(struct rcu_head *rhp) { free_sched_group(container_of(rhp, struct task_group, rcu)); } void sched_destroy_group(struct task_group *tg) { unsigned long flags; int i; for_each_possible_cpu(i) unregister_fair_sched_group(tg, i); spin_lock_irqsave(&task_group_lock, flags); list_del_rcu(&tg->list); list_del_rcu(&tg->siblings); spin_unlock_irqrestore(&task_group_lock, flags); call_rcu(&tg->rcu, free_sched_group_rcu); } void sched_move_task(struct task_struct *tsk) { int on_rq, running; unsigned long flags; struct rq *rq; rq = task_rq_lock(tsk, &flags); running = task_current(rq, tsk); on_rq = tsk->on_rq; if (on_rq) dequeue_task(rq, tsk, 0); if (unlikely(running)) tsk->sched_class->put_prev_task(rq, tsk); #ifdef CONFIG_FAIR_GROUP_SCHED if (tsk->sched_class->task_move_group) tsk->sched_class->task_move_group(tsk, on_rq); else #endif set_task_rq(tsk, task_cpu(tsk)); if (unlikely(running)) tsk->sched_class->set_curr_task(rq); if (on_rq) enqueue_task(rq, tsk, 0); task_rq_unlock(rq, tsk, &flags); } #endif #if defined(CONFIG_RT_GROUP_SCHED) || defined(CONFIG_CFS_BANDWIDTH) static unsigned long to_ratio(u64 period, u64 runtime) { if (runtime == RUNTIME_INF) return 1ULL << 20; return div64_u64(runtime << 20, period); } #endif #ifdef CONFIG_RT_GROUP_SCHED static DEFINE_MUTEX(rt_constraints_mutex); static inline int tg_has_rt_tasks(struct task_group *tg) { struct task_struct *g, *p; do_each_thread(g, p) { if (rt_task(p) && task_rq(p)->rt.tg == tg) return 1; } while_each_thread(g, p); return 0; } struct rt_schedulable_data { struct task_group *tg; u64 rt_period; u64 rt_runtime; }; static int tg_rt_schedulable(struct task_group *tg, void *data) { struct rt_schedulable_data *d = data; struct task_group *child; unsigned long total, sum = 0; u64 period, runtime; period = ktime_to_ns(tg->rt_bandwidth.rt_period); runtime = tg->rt_bandwidth.rt_runtime; if (tg == d->tg) { period = d->rt_period; runtime = d->rt_runtime; } if (runtime > period && runtime != RUNTIME_INF) return -EINVAL; if (rt_bandwidth_enabled() && !runtime && tg_has_rt_tasks(tg)) return -EBUSY; total = to_ratio(period, runtime); if (total > to_ratio(global_rt_period(), global_rt_runtime())) return -EINVAL; list_for_each_entry_rcu(child, &tg->children, siblings) { period = ktime_to_ns(child->rt_bandwidth.rt_period); runtime = child->rt_bandwidth.rt_runtime; if (child == d->tg) { period = d->rt_period; runtime = d->rt_runtime; } sum += to_ratio(period, runtime); } if (sum > total) return -EINVAL; return 0; } static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime) { int ret; struct rt_schedulable_data data = { .tg = tg, .rt_period = period, .rt_runtime = runtime, }; rcu_read_lock(); ret = walk_tg_tree(tg_rt_schedulable, tg_nop, &data); rcu_read_unlock(); return ret; } static int tg_set_rt_bandwidth(struct task_group *tg, u64 rt_period, u64 rt_runtime) { int i, err = 0; mutex_lock(&rt_constraints_mutex); read_lock(&tasklist_lock); err = __rt_schedulable(tg, rt_period, rt_runtime); if (err) goto unlock; raw_spin_lock_irq(&tg->rt_bandwidth.rt_runtime_lock); tg->rt_bandwidth.rt_period = ns_to_ktime(rt_period); tg->rt_bandwidth.rt_runtime = rt_runtime; for_each_possible_cpu(i) { struct rt_rq *rt_rq = tg->rt_rq[i]; raw_spin_lock(&rt_rq->rt_runtime_lock); rt_rq->rt_runtime = rt_runtime; raw_spin_unlock(&rt_rq->rt_runtime_lock); } raw_spin_unlock_irq(&tg->rt_bandwidth.rt_runtime_lock); unlock: read_unlock(&tasklist_lock); mutex_unlock(&rt_constraints_mutex); return err; } int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us) { u64 rt_runtime, rt_period; rt_period = ktime_to_ns(tg->rt_bandwidth.rt_period); rt_runtime = (u64)rt_runtime_us * NSEC_PER_USEC; if (rt_runtime_us < 0) rt_runtime = RUNTIME_INF; return tg_set_rt_bandwidth(tg, rt_period, rt_runtime); } long sched_group_rt_runtime(struct task_group *tg) { u64 rt_runtime_us; if (tg->rt_bandwidth.rt_runtime == RUNTIME_INF) return -1; rt_runtime_us = tg->rt_bandwidth.rt_runtime; do_div(rt_runtime_us, NSEC_PER_USEC); return rt_runtime_us; } int sched_group_set_rt_period(struct task_group *tg, long rt_period_us) { u64 rt_runtime, rt_period; rt_period = (u64)rt_period_us * NSEC_PER_USEC; rt_runtime = tg->rt_bandwidth.rt_runtime; if (rt_period == 0) return -EINVAL; return tg_set_rt_bandwidth(tg, rt_period, rt_runtime); } long sched_group_rt_period(struct task_group *tg) { u64 rt_period_us; rt_period_us = ktime_to_ns(tg->rt_bandwidth.rt_period); do_div(rt_period_us, NSEC_PER_USEC); return rt_period_us; } static int sched_rt_global_constraints(void) { u64 runtime, period; int ret = 0; if (sysctl_sched_rt_period <= 0) return -EINVAL; runtime = global_rt_runtime(); period = global_rt_period(); if (runtime > period && runtime != RUNTIME_INF) return -EINVAL; mutex_lock(&rt_constraints_mutex); read_lock(&tasklist_lock); ret = __rt_schedulable(NULL, 0, 0); read_unlock(&tasklist_lock); mutex_unlock(&rt_constraints_mutex); return ret; } int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk) { if (rt_task(tsk) && tg->rt_bandwidth.rt_runtime == 0) return 0; return 1; } #else static int sched_rt_global_constraints(void) { unsigned long flags; int i; if (sysctl_sched_rt_period <= 0) return -EINVAL; if (sysctl_sched_rt_runtime == 0) return -EBUSY; raw_spin_lock_irqsave(&def_rt_bandwidth.rt_runtime_lock, flags); for_each_possible_cpu(i) { struct rt_rq *rt_rq = &cpu_rq(i)->rt; raw_spin_lock(&rt_rq->rt_runtime_lock); rt_rq->rt_runtime = global_rt_runtime(); raw_spin_unlock(&rt_rq->rt_runtime_lock); } raw_spin_unlock_irqrestore(&def_rt_bandwidth.rt_runtime_lock, flags); return 0; } #endif int sched_rt_handler(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { int ret; int old_period, old_runtime; static DEFINE_MUTEX(mutex); mutex_lock(&mutex); old_period = sysctl_sched_rt_period; old_runtime = sysctl_sched_rt_runtime; ret = proc_dointvec(table, write, buffer, lenp, ppos); if (!ret && write) { ret = sched_rt_global_constraints(); if (ret) { sysctl_sched_rt_period = old_period; sysctl_sched_rt_runtime = old_runtime; } else { def_rt_bandwidth.rt_runtime = global_rt_runtime(); def_rt_bandwidth.rt_period = ns_to_ktime(global_rt_period()); } } mutex_unlock(&mutex); return ret; } #ifdef CONFIG_CGROUP_SCHED static inline struct task_group *cgroup_tg(struct cgroup *cgrp) { return container_of(cgroup_subsys_state(cgrp, cpu_cgroup_subsys_id), struct task_group, css); } static struct cgroup_subsys_state *cpu_cgroup_create(struct cgroup *cgrp) { struct task_group *tg, *parent; if (!cgrp->parent) { return &root_task_group.css; } parent = cgroup_tg(cgrp->parent); tg = sched_create_group(parent); if (IS_ERR(tg)) return ERR_PTR(-ENOMEM); return &tg->css; } static void cpu_cgroup_destroy(struct cgroup *cgrp) { struct task_group *tg = cgroup_tg(cgrp); sched_destroy_group(tg); } static int cpu_cgroup_allow_attach(struct cgroup *cgrp, struct cgroup_taskset *tset) { const struct cred *cred = current_cred(), *tcred; struct task_struct *task; cgroup_taskset_for_each(task, cgrp, tset) { tcred = __task_cred(task); if ((current != task) && !capable(CAP_SYS_NICE) && cred->euid != tcred->uid && cred->euid != tcred->suid) return -EACCES; } return 0; } static int cpu_cgroup_can_attach(struct cgroup *cgrp, struct cgroup_taskset *tset) { struct task_struct *task; cgroup_taskset_for_each(task, cgrp, tset) { #ifdef CONFIG_RT_GROUP_SCHED if (!sched_rt_can_attach(cgroup_tg(cgrp), task)) return -EINVAL; #else if (task->sched_class != &fair_sched_class) return -EINVAL; #endif } return 0; } static void cpu_cgroup_attach(struct cgroup *cgrp, struct cgroup_taskset *tset) { struct task_struct *task; cgroup_taskset_for_each(task, cgrp, tset) sched_move_task(task); } static void cpu_cgroup_exit(struct cgroup *cgrp, struct cgroup *old_cgrp, struct task_struct *task) { if (!(task->flags & PF_EXITING)) return; sched_move_task(task); } static u64 cpu_notify_on_migrate_read_u64(struct cgroup *cgrp, struct cftype *cft) { struct task_group *tg = cgroup_tg(cgrp); return tg->notify_on_migrate; } static int cpu_notify_on_migrate_write_u64(struct cgroup *cgrp, struct cftype *cft, u64 notify) { struct task_group *tg = cgroup_tg(cgrp); tg->notify_on_migrate = (notify > 0); return 0; } #ifdef CONFIG_FAIR_GROUP_SCHED static int cpu_shares_write_u64(struct cgroup *cgrp, struct cftype *cftype, u64 shareval) { return sched_group_set_shares(cgroup_tg(cgrp), scale_load(shareval)); } static u64 cpu_shares_read_u64(struct cgroup *cgrp, struct cftype *cft) { struct task_group *tg = cgroup_tg(cgrp); return (u64) scale_load_down(tg->shares); } #ifdef CONFIG_CFS_BANDWIDTH static DEFINE_MUTEX(cfs_constraints_mutex); const u64 max_cfs_quota_period = 1 * NSEC_PER_SEC; const u64 min_cfs_quota_period = 1 * NSEC_PER_MSEC; static int __cfs_schedulable(struct task_group *tg, u64 period, u64 runtime); static int tg_set_cfs_bandwidth(struct task_group *tg, u64 period, u64 quota) { int i, ret = 0, runtime_enabled, runtime_was_enabled; struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth; if (tg == &root_task_group) return -EINVAL; if (quota < min_cfs_quota_period || period < min_cfs_quota_period) return -EINVAL; if (period > max_cfs_quota_period) return -EINVAL; mutex_lock(&cfs_constraints_mutex); ret = __cfs_schedulable(tg, period, quota); if (ret) goto out_unlock; runtime_enabled = quota != RUNTIME_INF; runtime_was_enabled = cfs_b->quota != RUNTIME_INF; /* * If we need to toggle cfs_bandwidth_used, off->on must occur * before making related changes, and on->off must occur afterwards */ if (runtime_enabled && !runtime_was_enabled) cfs_bandwidth_usage_inc(); raw_spin_lock_irq(&cfs_b->lock); cfs_b->period = ns_to_ktime(period); cfs_b->quota = quota; __refill_cfs_bandwidth_runtime(cfs_b); if (runtime_enabled && cfs_b->timer_active) { cfs_b->timer_active = 0; __start_cfs_bandwidth(cfs_b); } raw_spin_unlock_irq(&cfs_b->lock); for_each_possible_cpu(i) { struct cfs_rq *cfs_rq = tg->cfs_rq[i]; struct rq *rq = cfs_rq->rq; raw_spin_lock_irq(&rq->lock); cfs_rq->runtime_enabled = runtime_enabled; cfs_rq->runtime_remaining = 0; if (cfs_rq->throttled) unthrottle_cfs_rq(cfs_rq); raw_spin_unlock_irq(&rq->lock); } if (runtime_was_enabled && !runtime_enabled) cfs_bandwidth_usage_dec(); out_unlock: mutex_unlock(&cfs_constraints_mutex); return ret; } int tg_set_cfs_quota(struct task_group *tg, long cfs_quota_us) { u64 quota, period; period = ktime_to_ns(tg->cfs_bandwidth.period); if (cfs_quota_us < 0) quota = RUNTIME_INF; else quota = (u64)cfs_quota_us * NSEC_PER_USEC; return tg_set_cfs_bandwidth(tg, period, quota); } long tg_get_cfs_quota(struct task_group *tg) { u64 quota_us; if (tg->cfs_bandwidth.quota == RUNTIME_INF) return -1; quota_us = tg->cfs_bandwidth.quota; do_div(quota_us, NSEC_PER_USEC); return quota_us; } int tg_set_cfs_period(struct task_group *tg, long cfs_period_us) { u64 quota, period; period = (u64)cfs_period_us * NSEC_PER_USEC; quota = tg->cfs_bandwidth.quota; return tg_set_cfs_bandwidth(tg, period, quota); } long tg_get_cfs_period(struct task_group *tg) { u64 cfs_period_us; cfs_period_us = ktime_to_ns(tg->cfs_bandwidth.period); do_div(cfs_period_us, NSEC_PER_USEC); return cfs_period_us; } static s64 cpu_cfs_quota_read_s64(struct cgroup *cgrp, struct cftype *cft) { return tg_get_cfs_quota(cgroup_tg(cgrp)); } static int cpu_cfs_quota_write_s64(struct cgroup *cgrp, struct cftype *cftype, s64 cfs_quota_us) { return tg_set_cfs_quota(cgroup_tg(cgrp), cfs_quota_us); } static u64 cpu_cfs_period_read_u64(struct cgroup *cgrp, struct cftype *cft) { return tg_get_cfs_period(cgroup_tg(cgrp)); } static int cpu_cfs_period_write_u64(struct cgroup *cgrp, struct cftype *cftype, u64 cfs_period_us) { return tg_set_cfs_period(cgroup_tg(cgrp), cfs_period_us); } struct cfs_schedulable_data { struct task_group *tg; u64 period, quota; }; static u64 normalize_cfs_quota(struct task_group *tg, struct cfs_schedulable_data *d) { u64 quota, period; if (tg == d->tg) { period = d->period; quota = d->quota; } else { period = tg_get_cfs_period(tg); quota = tg_get_cfs_quota(tg); } if (quota == RUNTIME_INF || quota == -1) return RUNTIME_INF; return to_ratio(period, quota); } static int tg_cfs_schedulable_down(struct task_group *tg, void *data) { struct cfs_schedulable_data *d = data; struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth; s64 quota = 0, parent_quota = -1; if (!tg->parent) { quota = RUNTIME_INF; } else { struct cfs_bandwidth *parent_b = &tg->parent->cfs_bandwidth; quota = normalize_cfs_quota(tg, d); parent_quota = parent_b->hierarchal_quota; if (quota == RUNTIME_INF) quota = parent_quota; else if (parent_quota != RUNTIME_INF && quota > parent_quota) return -EINVAL; } cfs_b->hierarchal_quota = quota; return 0; } static int __cfs_schedulable(struct task_group *tg, u64 period, u64 quota) { int ret; struct cfs_schedulable_data data = { .tg = tg, .period = period, .quota = quota, }; if (quota != RUNTIME_INF) { do_div(data.period, NSEC_PER_USEC); do_div(data.quota, NSEC_PER_USEC); } rcu_read_lock(); ret = walk_tg_tree(tg_cfs_schedulable_down, tg_nop, &data); rcu_read_unlock(); return ret; } static int cpu_stats_show(struct cgroup *cgrp, struct cftype *cft, struct cgroup_map_cb *cb) { struct task_group *tg = cgroup_tg(cgrp); struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth; cb->fill(cb, "nr_periods", cfs_b->nr_periods); cb->fill(cb, "nr_throttled", cfs_b->nr_throttled); cb->fill(cb, "throttled_time", cfs_b->throttled_time); return 0; } #endif #endif #ifdef CONFIG_RT_GROUP_SCHED static int cpu_rt_runtime_write(struct cgroup *cgrp, struct cftype *cft, s64 val) { return sched_group_set_rt_runtime(cgroup_tg(cgrp), val); } static s64 cpu_rt_runtime_read(struct cgroup *cgrp, struct cftype *cft) { return sched_group_rt_runtime(cgroup_tg(cgrp)); } static int cpu_rt_period_write_uint(struct cgroup *cgrp, struct cftype *cftype, u64 rt_period_us) { return sched_group_set_rt_period(cgroup_tg(cgrp), rt_period_us); } static u64 cpu_rt_period_read_uint(struct cgroup *cgrp, struct cftype *cft) { return sched_group_rt_period(cgroup_tg(cgrp)); } #endif static struct cftype cpu_files[] = { { .name = "notify_on_migrate", .read_u64 = cpu_notify_on_migrate_read_u64, .write_u64 = cpu_notify_on_migrate_write_u64, }, #ifdef CONFIG_FAIR_GROUP_SCHED { .name = "shares", .read_u64 = cpu_shares_read_u64, .write_u64 = cpu_shares_write_u64, }, #endif #ifdef CONFIG_CFS_BANDWIDTH { .name = "cfs_quota_us", .read_s64 = cpu_cfs_quota_read_s64, .write_s64 = cpu_cfs_quota_write_s64, }, { .name = "cfs_period_us", .read_u64 = cpu_cfs_period_read_u64, .write_u64 = cpu_cfs_period_write_u64, }, { .name = "stat", .read_map = cpu_stats_show, }, #endif #ifdef CONFIG_RT_GROUP_SCHED { .name = "rt_runtime_us", .read_s64 = cpu_rt_runtime_read, .write_s64 = cpu_rt_runtime_write, }, { .name = "rt_period_us", .read_u64 = cpu_rt_period_read_uint, .write_u64 = cpu_rt_period_write_uint, }, #endif }; static int cpu_cgroup_populate(struct cgroup_subsys *ss, struct cgroup *cont) { return cgroup_add_files(cont, ss, cpu_files, ARRAY_SIZE(cpu_files)); } struct cgroup_subsys cpu_cgroup_subsys = { .name = "cpu", .create = cpu_cgroup_create, .destroy = cpu_cgroup_destroy, .can_attach = cpu_cgroup_can_attach, .attach = cpu_cgroup_attach, .allow_attach = cpu_cgroup_allow_attach, .exit = cpu_cgroup_exit, .populate = cpu_cgroup_populate, .subsys_id = cpu_cgroup_subsys_id, .early_init = 1, }; #endif #ifdef CONFIG_CGROUP_CPUACCT static struct cgroup_subsys_state *cpuacct_create(struct cgroup *cgrp) { struct cpuacct *ca; if (!cgrp->parent) return &root_cpuacct.css; ca = kzalloc(sizeof(*ca), GFP_KERNEL); if (!ca) goto out; ca->cpuusage = alloc_percpu(u64); if (!ca->cpuusage) goto out_free_ca; ca->cpustat = alloc_percpu(struct kernel_cpustat); if (!ca->cpustat) goto out_free_cpuusage; return &ca->css; out_free_cpuusage: free_percpu(ca->cpuusage); out_free_ca: kfree(ca); out: return ERR_PTR(-ENOMEM); } static void cpuacct_destroy(struct cgroup *cgrp) { struct cpuacct *ca = cgroup_ca(cgrp); free_percpu(ca->cpustat); free_percpu(ca->cpuusage); kfree(ca); } static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu) { u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu); u64 data; #ifndef CONFIG_64BIT raw_spin_lock_irq(&cpu_rq(cpu)->lock); data = *cpuusage; raw_spin_unlock_irq(&cpu_rq(cpu)->lock); #else data = *cpuusage; #endif return data; } static void cpuacct_cpuusage_write(struct cpuacct *ca, int cpu, u64 val) { u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu); #ifndef CONFIG_64BIT raw_spin_lock_irq(&cpu_rq(cpu)->lock); *cpuusage = val; raw_spin_unlock_irq(&cpu_rq(cpu)->lock); #else *cpuusage = val; #endif } static u64 cpuusage_read(struct cgroup *cgrp, struct cftype *cft) { struct cpuacct *ca = cgroup_ca(cgrp); u64 totalcpuusage = 0; int i; for_each_present_cpu(i) totalcpuusage += cpuacct_cpuusage_read(ca, i); return totalcpuusage; } static int cpuusage_write(struct cgroup *cgrp, struct cftype *cftype, u64 reset) { struct cpuacct *ca = cgroup_ca(cgrp); int err = 0; int i; if (reset) { err = -EINVAL; goto out; } for_each_present_cpu(i) cpuacct_cpuusage_write(ca, i, 0); out: return err; } static int cpuacct_percpu_seq_read(struct cgroup *cgroup, struct cftype *cft, struct seq_file *m) { struct cpuacct *ca = cgroup_ca(cgroup); u64 percpu; int i; for_each_present_cpu(i) { percpu = cpuacct_cpuusage_read(ca, i); seq_printf(m, "%llu ", (unsigned long long) percpu); } seq_printf(m, "\n"); return 0; } static const char *cpuacct_stat_desc[] = { [CPUACCT_STAT_USER] = "user", [CPUACCT_STAT_SYSTEM] = "system", }; static int cpuacct_stats_show(struct cgroup *cgrp, struct cftype *cft, struct cgroup_map_cb *cb) { struct cpuacct *ca = cgroup_ca(cgrp); int cpu; s64 val = 0; for_each_online_cpu(cpu) { struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu); val += kcpustat->cpustat[CPUTIME_USER]; val += kcpustat->cpustat[CPUTIME_NICE]; } val = cputime64_to_clock_t(val); cb->fill(cb, cpuacct_stat_desc[CPUACCT_STAT_USER], val); val = 0; for_each_online_cpu(cpu) { struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu); val += kcpustat->cpustat[CPUTIME_SYSTEM]; val += kcpustat->cpustat[CPUTIME_IRQ]; val += kcpustat->cpustat[CPUTIME_SOFTIRQ]; } val = cputime64_to_clock_t(val); cb->fill(cb, cpuacct_stat_desc[CPUACCT_STAT_SYSTEM], val); return 0; } static struct cftype files[] = { { .name = "usage", .read_u64 = cpuusage_read, .write_u64 = cpuusage_write, }, { .name = "usage_percpu", .read_seq_string = cpuacct_percpu_seq_read, }, { .name = "stat", .read_map = cpuacct_stats_show, }, }; static int cpuacct_populate(struct cgroup_subsys *ss, struct cgroup *cgrp) { return cgroup_add_files(cgrp, ss, files, ARRAY_SIZE(files)); } void cpuacct_charge(struct task_struct *tsk, u64 cputime) { struct cpuacct *ca; int cpu; if (unlikely(!cpuacct_subsys.active)) return; cpu = task_cpu(tsk); rcu_read_lock(); ca = task_ca(tsk); for (; ca; ca = parent_ca(ca)) { u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu); *cpuusage += cputime; } rcu_read_unlock(); } struct cgroup_subsys cpuacct_subsys = { .name = "cpuacct", .create = cpuacct_create, .destroy = cpuacct_destroy, .populate = cpuacct_populate, .subsys_id = cpuacct_subsys_id, }; #endif