2 #include <linux/sched.h>
3 #include <linux/sched/sysctl.h>
4 #include <linux/sched/rt.h>
5 #include <linux/sched/deadline.h>
6 #include <linux/binfmts.h>
7 #include <linux/mutex.h>
8 #include <linux/spinlock.h>
9 #include <linux/stop_machine.h>
10 #include <linux/irq_work.h>
11 #include <linux/tick.h>
12 #include <linux/slab.h>
15 #include "cpudeadline.h"
21 /* task_struct::on_rq states: */
22 #define TASK_ON_RQ_QUEUED 1
23 #define TASK_ON_RQ_MIGRATING 2
25 extern __read_mostly int scheduler_running;
27 extern unsigned long calc_load_update;
28 extern atomic_long_t calc_load_tasks;
30 extern void calc_global_load_tick(struct rq *this_rq);
31 extern long calc_load_fold_active(struct rq *this_rq);
34 extern void cpu_load_update_active(struct rq *this_rq);
36 static inline void cpu_load_update_active(struct rq *this_rq) { }
40 * Helpers for converting nanosecond timing to jiffy resolution
42 #define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
45 * Increase resolution of nice-level calculations for 64-bit architectures.
46 * The extra resolution improves shares distribution and load balancing of
47 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
48 * hierarchies, especially on larger systems. This is not a user-visible change
49 * and does not change the user-interface for setting shares/weights.
51 * We increase resolution only if we have enough bits to allow this increased
52 * resolution (i.e. BITS_PER_LONG > 32). The costs for increasing resolution
53 * when BITS_PER_LONG <= 32 are pretty high and the returns do not justify the
56 #if 0 /* BITS_PER_LONG > 32 -- currently broken: it increases power usage under light load */
57 # define SCHED_LOAD_RESOLUTION 10
58 # define scale_load(w) ((w) << SCHED_LOAD_RESOLUTION)
59 # define scale_load_down(w) ((w) >> SCHED_LOAD_RESOLUTION)
61 # define SCHED_LOAD_RESOLUTION 0
62 # define scale_load(w) (w)
63 # define scale_load_down(w) (w)
66 #define SCHED_LOAD_SHIFT (10 + SCHED_LOAD_RESOLUTION)
67 #define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT)
69 #define NICE_0_LOAD SCHED_LOAD_SCALE
70 #define NICE_0_SHIFT SCHED_LOAD_SHIFT
73 * Single value that decides SCHED_DEADLINE internal math precision.
74 * 10 -> just above 1us
75 * 9 -> just above 0.5us
80 * These are the 'tuning knobs' of the scheduler:
84 * single value that denotes runtime == period, ie unlimited time.
86 #define RUNTIME_INF ((u64)~0ULL)
88 static inline int idle_policy(int policy)
90 return policy == SCHED_IDLE;
92 static inline int fair_policy(int policy)
94 return policy == SCHED_NORMAL || policy == SCHED_BATCH;
97 static inline int rt_policy(int policy)
99 return policy == SCHED_FIFO || policy == SCHED_RR;
102 static inline int dl_policy(int policy)
104 return policy == SCHED_DEADLINE;
106 static inline bool valid_policy(int policy)
108 return idle_policy(policy) || fair_policy(policy) ||
109 rt_policy(policy) || dl_policy(policy);
112 static inline int task_has_rt_policy(struct task_struct *p)
114 return rt_policy(p->policy);
117 static inline int task_has_dl_policy(struct task_struct *p)
119 return dl_policy(p->policy);
123 * Tells if entity @a should preempt entity @b.
126 dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
128 return dl_time_before(a->deadline, b->deadline);
132 * This is the priority-queue data structure of the RT scheduling class:
134 struct rt_prio_array {
135 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
136 struct list_head queue[MAX_RT_PRIO];
139 struct rt_bandwidth {
140 /* nests inside the rq lock: */
141 raw_spinlock_t rt_runtime_lock;
144 struct hrtimer rt_period_timer;
145 unsigned int rt_period_active;
148 void __dl_clear_params(struct task_struct *p);
151 * To keep the bandwidth of -deadline tasks and groups under control
152 * we need some place where:
153 * - store the maximum -deadline bandwidth of the system (the group);
154 * - cache the fraction of that bandwidth that is currently allocated.
156 * This is all done in the data structure below. It is similar to the
157 * one used for RT-throttling (rt_bandwidth), with the main difference
158 * that, since here we are only interested in admission control, we
159 * do not decrease any runtime while the group "executes", neither we
160 * need a timer to replenish it.
162 * With respect to SMP, the bandwidth is given on a per-CPU basis,
164 * - dl_bw (< 100%) is the bandwidth of the system (group) on each CPU;
165 * - dl_total_bw array contains, in the i-eth element, the currently
166 * allocated bandwidth on the i-eth CPU.
167 * Moreover, groups consume bandwidth on each CPU, while tasks only
168 * consume bandwidth on the CPU they're running on.
169 * Finally, dl_total_bw_cpu is used to cache the index of dl_total_bw
170 * that will be shown the next time the proc or cgroup controls will
171 * be red. It on its turn can be changed by writing on its own
174 struct dl_bandwidth {
175 raw_spinlock_t dl_runtime_lock;
180 static inline int dl_bandwidth_enabled(void)
182 return sysctl_sched_rt_runtime >= 0;
185 extern struct dl_bw *dl_bw_of(int i);
193 void __dl_clear(struct dl_bw *dl_b, u64 tsk_bw)
195 dl_b->total_bw -= tsk_bw;
199 void __dl_add(struct dl_bw *dl_b, u64 tsk_bw)
201 dl_b->total_bw += tsk_bw;
205 bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw)
207 return dl_b->bw != -1 &&
208 dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw;
211 extern struct mutex sched_domains_mutex;
213 #ifdef CONFIG_CGROUP_SCHED
215 #include <linux/cgroup.h>
220 extern struct list_head task_groups;
222 struct cfs_bandwidth {
223 #ifdef CONFIG_CFS_BANDWIDTH
227 s64 hierarchical_quota;
230 int idle, period_active;
231 struct hrtimer period_timer, slack_timer;
232 struct list_head throttled_cfs_rq;
235 int nr_periods, nr_throttled;
240 /* task group related information */
242 struct cgroup_subsys_state css;
244 #ifdef CONFIG_FAIR_GROUP_SCHED
245 /* schedulable entities of this group on each cpu */
246 struct sched_entity **se;
247 /* runqueue "owned" by this group on each cpu */
248 struct cfs_rq **cfs_rq;
249 unsigned long shares;
253 * load_avg can be heavily contended at clock tick time, so put
254 * it in its own cacheline separated from the fields above which
255 * will also be accessed at each tick.
257 atomic_long_t load_avg ____cacheline_aligned;
261 #ifdef CONFIG_RT_GROUP_SCHED
262 struct sched_rt_entity **rt_se;
263 struct rt_rq **rt_rq;
265 struct rt_bandwidth rt_bandwidth;
269 struct list_head list;
271 struct task_group *parent;
272 struct list_head siblings;
273 struct list_head children;
275 #ifdef CONFIG_SCHED_AUTOGROUP
276 struct autogroup *autogroup;
279 struct cfs_bandwidth cfs_bandwidth;
282 #ifdef CONFIG_FAIR_GROUP_SCHED
283 #define ROOT_TASK_GROUP_LOAD NICE_0_LOAD
286 * A weight of 0 or 1 can cause arithmetics problems.
287 * A weight of a cfs_rq is the sum of weights of which entities
288 * are queued on this cfs_rq, so a weight of a entity should not be
289 * too large, so as the shares value of a task group.
290 * (The default weight is 1024 - so there's no practical
291 * limitation from this.)
293 #define MIN_SHARES (1UL << 1)
294 #define MAX_SHARES (1UL << 18)
297 typedef int (*tg_visitor)(struct task_group *, void *);
299 extern int walk_tg_tree_from(struct task_group *from,
300 tg_visitor down, tg_visitor up, void *data);
303 * Iterate the full tree, calling @down when first entering a node and @up when
304 * leaving it for the final time.
306 * Caller must hold rcu_lock or sufficient equivalent.
308 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
310 return walk_tg_tree_from(&root_task_group, down, up, data);
313 extern int tg_nop(struct task_group *tg, void *data);
315 extern void free_fair_sched_group(struct task_group *tg);
316 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
317 extern void unregister_fair_sched_group(struct task_group *tg);
318 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
319 struct sched_entity *se, int cpu,
320 struct sched_entity *parent);
321 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
323 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
324 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
325 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
327 extern void free_rt_sched_group(struct task_group *tg);
328 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
329 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
330 struct sched_rt_entity *rt_se, int cpu,
331 struct sched_rt_entity *parent);
333 extern struct task_group *sched_create_group(struct task_group *parent);
334 extern void sched_online_group(struct task_group *tg,
335 struct task_group *parent);
336 extern void sched_destroy_group(struct task_group *tg);
337 extern void sched_offline_group(struct task_group *tg);
339 extern void sched_move_task(struct task_struct *tsk);
341 #ifdef CONFIG_FAIR_GROUP_SCHED
342 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
345 extern void set_task_rq_fair(struct sched_entity *se,
346 struct cfs_rq *prev, struct cfs_rq *next);
347 #else /* !CONFIG_SMP */
348 static inline void set_task_rq_fair(struct sched_entity *se,
349 struct cfs_rq *prev, struct cfs_rq *next) { }
350 #endif /* CONFIG_SMP */
351 #endif /* CONFIG_FAIR_GROUP_SCHED */
353 #else /* CONFIG_CGROUP_SCHED */
355 struct cfs_bandwidth { };
357 #endif /* CONFIG_CGROUP_SCHED */
359 /* CFS-related fields in a runqueue */
361 struct load_weight load;
362 unsigned int nr_running, h_nr_running;
367 u64 min_vruntime_copy;
370 struct rb_root tasks_timeline;
371 struct rb_node *rb_leftmost;
374 * 'curr' points to currently running entity on this cfs_rq.
375 * It is set to NULL otherwise (i.e when none are currently running).
377 struct sched_entity *curr, *next, *last, *skip;
379 #ifdef CONFIG_SCHED_DEBUG
380 unsigned int nr_spread_over;
387 struct sched_avg avg;
388 u64 runnable_load_sum;
389 unsigned long runnable_load_avg;
390 #ifdef CONFIG_FAIR_GROUP_SCHED
391 unsigned long tg_load_avg_contrib;
393 atomic_long_t removed_load_avg, removed_util_avg;
395 u64 load_last_update_time_copy;
398 #ifdef CONFIG_FAIR_GROUP_SCHED
400 * h_load = weight * f(tg)
402 * Where f(tg) is the recursive weight fraction assigned to
405 unsigned long h_load;
406 u64 last_h_load_update;
407 struct sched_entity *h_load_next;
408 #endif /* CONFIG_FAIR_GROUP_SCHED */
409 #endif /* CONFIG_SMP */
411 #ifdef CONFIG_FAIR_GROUP_SCHED
412 struct rq *rq; /* cpu runqueue to which this cfs_rq is attached */
415 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
416 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
417 * (like users, containers etc.)
419 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This
420 * list is used during load balance.
423 struct list_head leaf_cfs_rq_list;
424 struct task_group *tg; /* group that "owns" this runqueue */
426 #ifdef CONFIG_CFS_BANDWIDTH
429 s64 runtime_remaining;
431 u64 throttled_clock, throttled_clock_task;
432 u64 throttled_clock_task_time;
433 int throttled, throttle_count;
434 struct list_head throttled_list;
435 #endif /* CONFIG_CFS_BANDWIDTH */
436 #endif /* CONFIG_FAIR_GROUP_SCHED */
439 static inline int rt_bandwidth_enabled(void)
441 return sysctl_sched_rt_runtime >= 0;
444 /* RT IPI pull logic requires IRQ_WORK */
445 #ifdef CONFIG_IRQ_WORK
446 # define HAVE_RT_PUSH_IPI
449 /* Real-Time classes' related field in a runqueue: */
451 struct rt_prio_array active;
452 unsigned int rt_nr_running;
453 unsigned int rr_nr_running;
454 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
456 int curr; /* highest queued rt task prio */
458 int next; /* next highest */
463 unsigned long rt_nr_migratory;
464 unsigned long rt_nr_total;
466 struct plist_head pushable_tasks;
467 #ifdef HAVE_RT_PUSH_IPI
470 struct irq_work push_work;
471 raw_spinlock_t push_lock;
473 #endif /* CONFIG_SMP */
479 /* Nests inside the rq lock: */
480 raw_spinlock_t rt_runtime_lock;
482 #ifdef CONFIG_RT_GROUP_SCHED
483 unsigned long rt_nr_boosted;
486 struct task_group *tg;
490 /* Deadline class' related fields in a runqueue */
492 /* runqueue is an rbtree, ordered by deadline */
493 struct rb_root rb_root;
494 struct rb_node *rb_leftmost;
496 unsigned long dl_nr_running;
500 * Deadline values of the currently executing and the
501 * earliest ready task on this rq. Caching these facilitates
502 * the decision wether or not a ready but not running task
503 * should migrate somewhere else.
510 unsigned long dl_nr_migratory;
514 * Tasks on this rq that can be pushed away. They are kept in
515 * an rb-tree, ordered by tasks' deadlines, with caching
516 * of the leftmost (earliest deadline) element.
518 struct rb_root pushable_dl_tasks_root;
519 struct rb_node *pushable_dl_tasks_leftmost;
528 * We add the notion of a root-domain which will be used to define per-domain
529 * variables. Each exclusive cpuset essentially defines an island domain by
530 * fully partitioning the member cpus from any other cpuset. Whenever a new
531 * exclusive cpuset is created, we also create and attach a new root-domain
540 cpumask_var_t online;
542 /* Indicate more than one runnable task for any CPU */
546 * The bit corresponding to a CPU gets set here if such CPU has more
547 * than one runnable -deadline task (as it is below for RT tasks).
549 cpumask_var_t dlo_mask;
555 * The "RT overload" flag: it gets set if a CPU has more than
556 * one runnable RT task.
558 cpumask_var_t rto_mask;
559 struct cpupri cpupri;
562 extern struct root_domain def_root_domain;
564 #endif /* CONFIG_SMP */
567 * This is the main, per-CPU runqueue data structure.
569 * Locking rule: those places that want to lock multiple runqueues
570 * (such as the load balancing or the thread migration code), lock
571 * acquire operations must be ordered by ascending &runqueue.
578 * nr_running and cpu_load should be in the same cacheline because
579 * remote CPUs use both these fields when doing load calculation.
581 unsigned int nr_running;
582 #ifdef CONFIG_NUMA_BALANCING
583 unsigned int nr_numa_running;
584 unsigned int nr_preferred_running;
586 #define CPU_LOAD_IDX_MAX 5
587 unsigned long cpu_load[CPU_LOAD_IDX_MAX];
588 unsigned long last_load_update_tick;
589 #ifdef CONFIG_NO_HZ_COMMON
591 unsigned long nohz_flags;
593 #ifdef CONFIG_NO_HZ_FULL
594 unsigned long last_sched_tick;
596 /* capture load from *all* tasks on this cpu: */
597 struct load_weight load;
598 unsigned long nr_load_updates;
605 #ifdef CONFIG_FAIR_GROUP_SCHED
606 /* list of leaf cfs_rq on this cpu: */
607 struct list_head leaf_cfs_rq_list;
608 #endif /* CONFIG_FAIR_GROUP_SCHED */
611 * This is part of a global counter where only the total sum
612 * over all CPUs matters. A task can increase this counter on
613 * one CPU and if it got migrated afterwards it may decrease
614 * it on another CPU. Always updated under the runqueue lock:
616 unsigned long nr_uninterruptible;
618 struct task_struct *curr, *idle, *stop;
619 unsigned long next_balance;
620 struct mm_struct *prev_mm;
622 unsigned int clock_skip_update;
629 struct root_domain *rd;
630 struct sched_domain *sd;
632 unsigned long cpu_capacity;
633 unsigned long cpu_capacity_orig;
635 struct callback_head *balance_callback;
637 unsigned char idle_balance;
638 /* For active balancing */
641 struct cpu_stop_work active_balance_work;
642 /* cpu of this runqueue: */
646 struct list_head cfs_tasks;
653 /* This is used to determine avg_idle's max value */
654 u64 max_idle_balance_cost;
657 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
660 #ifdef CONFIG_PARAVIRT
663 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
664 u64 prev_steal_time_rq;
667 /* calc_load related fields */
668 unsigned long calc_load_update;
669 long calc_load_active;
671 #ifdef CONFIG_SCHED_HRTICK
673 int hrtick_csd_pending;
674 struct call_single_data hrtick_csd;
676 struct hrtimer hrtick_timer;
679 #ifdef CONFIG_SCHEDSTATS
681 struct sched_info rq_sched_info;
682 unsigned long long rq_cpu_time;
683 /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
685 /* sys_sched_yield() stats */
686 unsigned int yld_count;
688 /* schedule() stats */
689 unsigned int sched_count;
690 unsigned int sched_goidle;
692 /* try_to_wake_up() stats */
693 unsigned int ttwu_count;
694 unsigned int ttwu_local;
698 struct llist_head wake_list;
701 #ifdef CONFIG_CPU_IDLE
702 /* Must be inspected within a rcu lock section */
703 struct cpuidle_state *idle_state;
707 static inline int cpu_of(struct rq *rq)
716 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
718 #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
719 #define this_rq() this_cpu_ptr(&runqueues)
720 #define task_rq(p) cpu_rq(task_cpu(p))
721 #define cpu_curr(cpu) (cpu_rq(cpu)->curr)
722 #define raw_rq() raw_cpu_ptr(&runqueues)
724 static inline u64 __rq_clock_broken(struct rq *rq)
726 return READ_ONCE(rq->clock);
729 static inline u64 rq_clock(struct rq *rq)
731 lockdep_assert_held(&rq->lock);
735 static inline u64 rq_clock_task(struct rq *rq)
737 lockdep_assert_held(&rq->lock);
738 return rq->clock_task;
741 #define RQCF_REQ_SKIP 0x01
742 #define RQCF_ACT_SKIP 0x02
744 static inline void rq_clock_skip_update(struct rq *rq, bool skip)
746 lockdep_assert_held(&rq->lock);
748 rq->clock_skip_update |= RQCF_REQ_SKIP;
750 rq->clock_skip_update &= ~RQCF_REQ_SKIP;
754 enum numa_topology_type {
759 extern enum numa_topology_type sched_numa_topology_type;
760 extern int sched_max_numa_distance;
761 extern bool find_numa_distance(int distance);
764 #ifdef CONFIG_NUMA_BALANCING
765 /* The regions in numa_faults array from task_struct */
766 enum numa_faults_stats {
772 extern void sched_setnuma(struct task_struct *p, int node);
773 extern int migrate_task_to(struct task_struct *p, int cpu);
774 extern int migrate_swap(struct task_struct *, struct task_struct *);
775 #endif /* CONFIG_NUMA_BALANCING */
780 queue_balance_callback(struct rq *rq,
781 struct callback_head *head,
782 void (*func)(struct rq *rq))
784 lockdep_assert_held(&rq->lock);
786 if (unlikely(head->next))
789 head->func = (void (*)(struct callback_head *))func;
790 head->next = rq->balance_callback;
791 rq->balance_callback = head;
794 extern void sched_ttwu_pending(void);
796 #define rcu_dereference_check_sched_domain(p) \
797 rcu_dereference_check((p), \
798 lockdep_is_held(&sched_domains_mutex))
801 * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
802 * See detach_destroy_domains: synchronize_sched for details.
804 * The domain tree of any CPU may only be accessed from within
805 * preempt-disabled sections.
807 #define for_each_domain(cpu, __sd) \
808 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
809 __sd; __sd = __sd->parent)
811 #define for_each_lower_domain(sd) for (; sd; sd = sd->child)
814 * highest_flag_domain - Return highest sched_domain containing flag.
815 * @cpu: The cpu whose highest level of sched domain is to
817 * @flag: The flag to check for the highest sched_domain
820 * Returns the highest sched_domain of a cpu which contains the given flag.
822 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
824 struct sched_domain *sd, *hsd = NULL;
826 for_each_domain(cpu, sd) {
827 if (!(sd->flags & flag))
835 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
837 struct sched_domain *sd;
839 for_each_domain(cpu, sd) {
840 if (sd->flags & flag)
847 DECLARE_PER_CPU(struct sched_domain *, sd_llc);
848 DECLARE_PER_CPU(int, sd_llc_size);
849 DECLARE_PER_CPU(int, sd_llc_id);
850 DECLARE_PER_CPU(struct sched_domain *, sd_numa);
851 DECLARE_PER_CPU(struct sched_domain *, sd_busy);
852 DECLARE_PER_CPU(struct sched_domain *, sd_asym);
854 struct sched_group_capacity {
857 * CPU capacity of this group, SCHED_LOAD_SCALE being max capacity
860 unsigned int capacity;
861 unsigned long next_update;
862 int imbalance; /* XXX unrelated to capacity but shared group state */
864 * Number of busy cpus in this group.
866 atomic_t nr_busy_cpus;
868 unsigned long cpumask[0]; /* iteration mask */
872 struct sched_group *next; /* Must be a circular list */
875 unsigned int group_weight;
876 struct sched_group_capacity *sgc;
879 * The CPUs this group covers.
881 * NOTE: this field is variable length. (Allocated dynamically
882 * by attaching extra space to the end of the structure,
883 * depending on how many CPUs the kernel has booted up with)
885 unsigned long cpumask[0];
888 static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
890 return to_cpumask(sg->cpumask);
894 * cpumask masking which cpus in the group are allowed to iterate up the domain
897 static inline struct cpumask *sched_group_mask(struct sched_group *sg)
899 return to_cpumask(sg->sgc->cpumask);
903 * group_first_cpu - Returns the first cpu in the cpumask of a sched_group.
904 * @group: The group whose first cpu is to be returned.
906 static inline unsigned int group_first_cpu(struct sched_group *group)
908 return cpumask_first(sched_group_cpus(group));
911 extern int group_balance_cpu(struct sched_group *sg);
913 #if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
914 void register_sched_domain_sysctl(void);
915 void unregister_sched_domain_sysctl(void);
917 static inline void register_sched_domain_sysctl(void)
920 static inline void unregister_sched_domain_sysctl(void)
927 static inline void sched_ttwu_pending(void) { }
929 #endif /* CONFIG_SMP */
932 #include "auto_group.h"
934 #ifdef CONFIG_CGROUP_SCHED
937 * Return the group to which this tasks belongs.
939 * We cannot use task_css() and friends because the cgroup subsystem
940 * changes that value before the cgroup_subsys::attach() method is called,
941 * therefore we cannot pin it and might observe the wrong value.
943 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
944 * core changes this before calling sched_move_task().
946 * Instead we use a 'copy' which is updated from sched_move_task() while
947 * holding both task_struct::pi_lock and rq::lock.
949 static inline struct task_group *task_group(struct task_struct *p)
951 return p->sched_task_group;
954 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
955 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
957 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
958 struct task_group *tg = task_group(p);
961 #ifdef CONFIG_FAIR_GROUP_SCHED
962 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
963 p->se.cfs_rq = tg->cfs_rq[cpu];
964 p->se.parent = tg->se[cpu];
967 #ifdef CONFIG_RT_GROUP_SCHED
968 p->rt.rt_rq = tg->rt_rq[cpu];
969 p->rt.parent = tg->rt_se[cpu];
973 #else /* CONFIG_CGROUP_SCHED */
975 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
976 static inline struct task_group *task_group(struct task_struct *p)
981 #endif /* CONFIG_CGROUP_SCHED */
983 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
988 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
989 * successfuly executed on another CPU. We must ensure that updates of
990 * per-task data have been completed by this moment.
993 task_thread_info(p)->cpu = cpu;
999 * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
1001 #ifdef CONFIG_SCHED_DEBUG
1002 # include <linux/static_key.h>
1003 # define const_debug __read_mostly
1005 # define const_debug const
1008 extern const_debug unsigned int sysctl_sched_features;
1010 #define SCHED_FEAT(name, enabled) \
1011 __SCHED_FEAT_##name ,
1014 #include "features.h"
1020 #if defined(CONFIG_SCHED_DEBUG) && defined(HAVE_JUMP_LABEL)
1021 #define SCHED_FEAT(name, enabled) \
1022 static __always_inline bool static_branch_##name(struct static_key *key) \
1024 return static_key_##enabled(key); \
1027 #include "features.h"
1031 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
1032 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
1033 #else /* !(SCHED_DEBUG && HAVE_JUMP_LABEL) */
1034 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1035 #endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */
1037 extern struct static_key_false sched_numa_balancing;
1038 extern struct static_key_false sched_schedstats;
1040 static inline u64 global_rt_period(void)
1042 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
1045 static inline u64 global_rt_runtime(void)
1047 if (sysctl_sched_rt_runtime < 0)
1050 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
1053 static inline int task_current(struct rq *rq, struct task_struct *p)
1055 return rq->curr == p;
1058 static inline int task_running(struct rq *rq, struct task_struct *p)
1063 return task_current(rq, p);
1067 static inline int task_on_rq_queued(struct task_struct *p)
1069 return p->on_rq == TASK_ON_RQ_QUEUED;
1072 static inline int task_on_rq_migrating(struct task_struct *p)
1074 return p->on_rq == TASK_ON_RQ_MIGRATING;
1077 #ifndef prepare_arch_switch
1078 # define prepare_arch_switch(next) do { } while (0)
1080 #ifndef finish_arch_post_lock_switch
1081 # define finish_arch_post_lock_switch() do { } while (0)
1084 static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
1088 * We can optimise this out completely for !SMP, because the
1089 * SMP rebalancing from interrupt is the only thing that cares
1096 static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
1100 * After ->on_cpu is cleared, the task can be moved to a different CPU.
1101 * We must ensure this doesn't happen until the switch is completely
1104 * In particular, the load of prev->state in finish_task_switch() must
1105 * happen before this.
1107 * Pairs with the smp_cond_acquire() in try_to_wake_up().
1109 smp_store_release(&prev->on_cpu, 0);
1111 #ifdef CONFIG_DEBUG_SPINLOCK
1112 /* this is a valid case when another task releases the spinlock */
1113 rq->lock.owner = current;
1116 * If we are tracking spinlock dependencies then we have to
1117 * fix up the runqueue lock - which gets 'carried over' from
1118 * prev into current:
1120 spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_);
1122 raw_spin_unlock_irq(&rq->lock);
1128 #define WF_SYNC 0x01 /* waker goes to sleep after wakeup */
1129 #define WF_FORK 0x02 /* child wakeup after fork */
1130 #define WF_MIGRATED 0x4 /* internal use, task got migrated */
1133 * To aid in avoiding the subversion of "niceness" due to uneven distribution
1134 * of tasks with abnormal "nice" values across CPUs the contribution that
1135 * each task makes to its run queue's load is weighted according to its
1136 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
1137 * scaled version of the new time slice allocation that they receive on time
1141 #define WEIGHT_IDLEPRIO 3
1142 #define WMULT_IDLEPRIO 1431655765
1144 extern const int sched_prio_to_weight[40];
1145 extern const u32 sched_prio_to_wmult[40];
1148 * {de,en}queue flags:
1150 * DEQUEUE_SLEEP - task is no longer runnable
1151 * ENQUEUE_WAKEUP - task just became runnable
1153 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
1154 * are in a known state which allows modification. Such pairs
1155 * should preserve as much state as possible.
1157 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
1160 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified)
1161 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
1162 * ENQUEUE_WAKING - sched_class::task_waking was called
1166 #define DEQUEUE_SLEEP 0x01
1167 #define DEQUEUE_SAVE 0x02 /* matches ENQUEUE_RESTORE */
1168 #define DEQUEUE_MOVE 0x04 /* matches ENQUEUE_MOVE */
1170 #define ENQUEUE_WAKEUP 0x01
1171 #define ENQUEUE_RESTORE 0x02
1172 #define ENQUEUE_MOVE 0x04
1174 #define ENQUEUE_HEAD 0x08
1175 #define ENQUEUE_REPLENISH 0x10
1177 #define ENQUEUE_WAKING 0x20
1179 #define ENQUEUE_WAKING 0x00
1182 #define RETRY_TASK ((void *)-1UL)
1184 struct sched_class {
1185 const struct sched_class *next;
1187 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1188 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1189 void (*yield_task) (struct rq *rq);
1190 bool (*yield_to_task) (struct rq *rq, struct task_struct *p, bool preempt);
1192 void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
1195 * It is the responsibility of the pick_next_task() method that will
1196 * return the next task to call put_prev_task() on the @prev task or
1197 * something equivalent.
1199 * May return RETRY_TASK when it finds a higher prio class has runnable
1202 struct task_struct * (*pick_next_task) (struct rq *rq,
1203 struct task_struct *prev);
1204 void (*put_prev_task) (struct rq *rq, struct task_struct *p);
1207 int (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
1208 void (*migrate_task_rq)(struct task_struct *p);
1210 void (*task_waking) (struct task_struct *task);
1211 void (*task_woken) (struct rq *this_rq, struct task_struct *task);
1213 void (*set_cpus_allowed)(struct task_struct *p,
1214 const struct cpumask *newmask);
1216 void (*rq_online)(struct rq *rq);
1217 void (*rq_offline)(struct rq *rq);
1220 void (*set_curr_task) (struct rq *rq);
1221 void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1222 void (*task_fork) (struct task_struct *p);
1223 void (*task_dead) (struct task_struct *p);
1226 * The switched_from() call is allowed to drop rq->lock, therefore we
1227 * cannot assume the switched_from/switched_to pair is serliazed by
1228 * rq->lock. They are however serialized by p->pi_lock.
1230 void (*switched_from) (struct rq *this_rq, struct task_struct *task);
1231 void (*switched_to) (struct rq *this_rq, struct task_struct *task);
1232 void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1235 unsigned int (*get_rr_interval) (struct rq *rq,
1236 struct task_struct *task);
1238 void (*update_curr) (struct rq *rq);
1240 #ifdef CONFIG_FAIR_GROUP_SCHED
1241 void (*task_move_group) (struct task_struct *p);
1245 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
1247 prev->sched_class->put_prev_task(rq, prev);
1250 #define sched_class_highest (&stop_sched_class)
1251 #define for_each_class(class) \
1252 for (class = sched_class_highest; class; class = class->next)
1254 extern const struct sched_class stop_sched_class;
1255 extern const struct sched_class dl_sched_class;
1256 extern const struct sched_class rt_sched_class;
1257 extern const struct sched_class fair_sched_class;
1258 extern const struct sched_class idle_sched_class;
1263 extern void update_group_capacity(struct sched_domain *sd, int cpu);
1265 extern void trigger_load_balance(struct rq *rq);
1267 extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask);
1271 #ifdef CONFIG_CPU_IDLE
1272 static inline void idle_set_state(struct rq *rq,
1273 struct cpuidle_state *idle_state)
1275 rq->idle_state = idle_state;
1278 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1280 WARN_ON(!rcu_read_lock_held());
1281 return rq->idle_state;
1284 static inline void idle_set_state(struct rq *rq,
1285 struct cpuidle_state *idle_state)
1289 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1295 extern void sysrq_sched_debug_show(void);
1296 extern void sched_init_granularity(void);
1297 extern void update_max_interval(void);
1299 extern void init_sched_dl_class(void);
1300 extern void init_sched_rt_class(void);
1301 extern void init_sched_fair_class(void);
1303 extern void resched_curr(struct rq *rq);
1304 extern void resched_cpu(int cpu);
1306 extern struct rt_bandwidth def_rt_bandwidth;
1307 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
1309 extern struct dl_bandwidth def_dl_bandwidth;
1310 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
1311 extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
1313 unsigned long to_ratio(u64 period, u64 runtime);
1315 extern void init_entity_runnable_average(struct sched_entity *se);
1316 extern void post_init_entity_util_avg(struct sched_entity *se);
1318 #ifdef CONFIG_NO_HZ_FULL
1319 extern bool sched_can_stop_tick(struct rq *rq);
1322 * Tick may be needed by tasks in the runqueue depending on their policy and
1323 * requirements. If tick is needed, lets send the target an IPI to kick it out of
1324 * nohz mode if necessary.
1326 static inline void sched_update_tick_dependency(struct rq *rq)
1330 if (!tick_nohz_full_enabled())
1335 if (!tick_nohz_full_cpu(cpu))
1338 if (sched_can_stop_tick(rq))
1339 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
1341 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
1344 static inline void sched_update_tick_dependency(struct rq *rq) { }
1347 static inline void add_nr_running(struct rq *rq, unsigned count)
1349 unsigned prev_nr = rq->nr_running;
1351 rq->nr_running = prev_nr + count;
1353 if (prev_nr < 2 && rq->nr_running >= 2) {
1355 if (!rq->rd->overload)
1356 rq->rd->overload = true;
1360 sched_update_tick_dependency(rq);
1363 static inline void sub_nr_running(struct rq *rq, unsigned count)
1365 rq->nr_running -= count;
1366 /* Check if we still need preemption */
1367 sched_update_tick_dependency(rq);
1370 static inline void rq_last_tick_reset(struct rq *rq)
1372 #ifdef CONFIG_NO_HZ_FULL
1373 rq->last_sched_tick = jiffies;
1377 extern void update_rq_clock(struct rq *rq);
1379 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
1380 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
1382 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
1384 extern const_debug unsigned int sysctl_sched_time_avg;
1385 extern const_debug unsigned int sysctl_sched_nr_migrate;
1386 extern const_debug unsigned int sysctl_sched_migration_cost;
1388 static inline u64 sched_avg_period(void)
1390 return (u64)sysctl_sched_time_avg * NSEC_PER_MSEC / 2;
1393 #ifdef CONFIG_SCHED_HRTICK
1397 * - enabled by features
1398 * - hrtimer is actually high res
1400 static inline int hrtick_enabled(struct rq *rq)
1402 if (!sched_feat(HRTICK))
1404 if (!cpu_active(cpu_of(rq)))
1406 return hrtimer_is_hres_active(&rq->hrtick_timer);
1409 void hrtick_start(struct rq *rq, u64 delay);
1413 static inline int hrtick_enabled(struct rq *rq)
1418 #endif /* CONFIG_SCHED_HRTICK */
1421 extern void sched_avg_update(struct rq *rq);
1423 #ifndef arch_scale_freq_capacity
1424 static __always_inline
1425 unsigned long arch_scale_freq_capacity(struct sched_domain *sd, int cpu)
1427 return SCHED_CAPACITY_SCALE;
1431 #ifndef arch_scale_cpu_capacity
1432 static __always_inline
1433 unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu)
1435 if (sd && (sd->flags & SD_SHARE_CPUCAPACITY) && (sd->span_weight > 1))
1436 return sd->smt_gain / sd->span_weight;
1438 return SCHED_CAPACITY_SCALE;
1442 static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
1444 rq->rt_avg += rt_delta * arch_scale_freq_capacity(NULL, cpu_of(rq));
1445 sched_avg_update(rq);
1448 static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { }
1449 static inline void sched_avg_update(struct rq *rq) { }
1453 * __task_rq_lock - lock the rq @p resides on.
1455 static inline struct rq *__task_rq_lock(struct task_struct *p)
1456 __acquires(rq->lock)
1460 lockdep_assert_held(&p->pi_lock);
1464 raw_spin_lock(&rq->lock);
1465 if (likely(rq == task_rq(p) && !task_on_rq_migrating(p))) {
1466 lockdep_pin_lock(&rq->lock);
1469 raw_spin_unlock(&rq->lock);
1471 while (unlikely(task_on_rq_migrating(p)))
1477 * task_rq_lock - lock p->pi_lock and lock the rq @p resides on.
1479 static inline struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags)
1480 __acquires(p->pi_lock)
1481 __acquires(rq->lock)
1486 raw_spin_lock_irqsave(&p->pi_lock, *flags);
1488 raw_spin_lock(&rq->lock);
1490 * move_queued_task() task_rq_lock()
1492 * ACQUIRE (rq->lock)
1493 * [S] ->on_rq = MIGRATING [L] rq = task_rq()
1494 * WMB (__set_task_cpu()) ACQUIRE (rq->lock);
1495 * [S] ->cpu = new_cpu [L] task_rq()
1497 * RELEASE (rq->lock)
1499 * If we observe the old cpu in task_rq_lock, the acquire of
1500 * the old rq->lock will fully serialize against the stores.
1502 * If we observe the new cpu in task_rq_lock, the acquire will
1503 * pair with the WMB to ensure we must then also see migrating.
1505 if (likely(rq == task_rq(p) && !task_on_rq_migrating(p))) {
1506 lockdep_pin_lock(&rq->lock);
1509 raw_spin_unlock(&rq->lock);
1510 raw_spin_unlock_irqrestore(&p->pi_lock, *flags);
1512 while (unlikely(task_on_rq_migrating(p)))
1517 static inline void __task_rq_unlock(struct rq *rq)
1518 __releases(rq->lock)
1520 lockdep_unpin_lock(&rq->lock);
1521 raw_spin_unlock(&rq->lock);
1525 task_rq_unlock(struct rq *rq, struct task_struct *p, unsigned long *flags)
1526 __releases(rq->lock)
1527 __releases(p->pi_lock)
1529 lockdep_unpin_lock(&rq->lock);
1530 raw_spin_unlock(&rq->lock);
1531 raw_spin_unlock_irqrestore(&p->pi_lock, *flags);
1535 #ifdef CONFIG_PREEMPT
1537 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2);
1540 * fair double_lock_balance: Safely acquires both rq->locks in a fair
1541 * way at the expense of forcing extra atomic operations in all
1542 * invocations. This assures that the double_lock is acquired using the
1543 * same underlying policy as the spinlock_t on this architecture, which
1544 * reduces latency compared to the unfair variant below. However, it
1545 * also adds more overhead and therefore may reduce throughput.
1547 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1548 __releases(this_rq->lock)
1549 __acquires(busiest->lock)
1550 __acquires(this_rq->lock)
1552 raw_spin_unlock(&this_rq->lock);
1553 double_rq_lock(this_rq, busiest);
1560 * Unfair double_lock_balance: Optimizes throughput at the expense of
1561 * latency by eliminating extra atomic operations when the locks are
1562 * already in proper order on entry. This favors lower cpu-ids and will
1563 * grant the double lock to lower cpus over higher ids under contention,
1564 * regardless of entry order into the function.
1566 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1567 __releases(this_rq->lock)
1568 __acquires(busiest->lock)
1569 __acquires(this_rq->lock)
1573 if (unlikely(!raw_spin_trylock(&busiest->lock))) {
1574 if (busiest < this_rq) {
1575 raw_spin_unlock(&this_rq->lock);
1576 raw_spin_lock(&busiest->lock);
1577 raw_spin_lock_nested(&this_rq->lock,
1578 SINGLE_DEPTH_NESTING);
1581 raw_spin_lock_nested(&busiest->lock,
1582 SINGLE_DEPTH_NESTING);
1587 #endif /* CONFIG_PREEMPT */
1590 * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
1592 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
1594 if (unlikely(!irqs_disabled())) {
1595 /* printk() doesn't work good under rq->lock */
1596 raw_spin_unlock(&this_rq->lock);
1600 return _double_lock_balance(this_rq, busiest);
1603 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
1604 __releases(busiest->lock)
1606 raw_spin_unlock(&busiest->lock);
1607 lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
1610 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
1616 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1619 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
1625 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1628 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
1634 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1638 * double_rq_lock - safely lock two runqueues
1640 * Note this does not disable interrupts like task_rq_lock,
1641 * you need to do so manually before calling.
1643 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
1644 __acquires(rq1->lock)
1645 __acquires(rq2->lock)
1647 BUG_ON(!irqs_disabled());
1649 raw_spin_lock(&rq1->lock);
1650 __acquire(rq2->lock); /* Fake it out ;) */
1653 raw_spin_lock(&rq1->lock);
1654 raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
1656 raw_spin_lock(&rq2->lock);
1657 raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
1663 * double_rq_unlock - safely unlock two runqueues
1665 * Note this does not restore interrupts like task_rq_unlock,
1666 * you need to do so manually after calling.
1668 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
1669 __releases(rq1->lock)
1670 __releases(rq2->lock)
1672 raw_spin_unlock(&rq1->lock);
1674 raw_spin_unlock(&rq2->lock);
1676 __release(rq2->lock);
1679 #else /* CONFIG_SMP */
1682 * double_rq_lock - safely lock two runqueues
1684 * Note this does not disable interrupts like task_rq_lock,
1685 * you need to do so manually before calling.
1687 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
1688 __acquires(rq1->lock)
1689 __acquires(rq2->lock)
1691 BUG_ON(!irqs_disabled());
1693 raw_spin_lock(&rq1->lock);
1694 __acquire(rq2->lock); /* Fake it out ;) */
1698 * double_rq_unlock - safely unlock two runqueues
1700 * Note this does not restore interrupts like task_rq_unlock,
1701 * you need to do so manually after calling.
1703 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
1704 __releases(rq1->lock)
1705 __releases(rq2->lock)
1708 raw_spin_unlock(&rq1->lock);
1709 __release(rq2->lock);
1714 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
1715 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
1717 #ifdef CONFIG_SCHED_DEBUG
1718 extern void print_cfs_stats(struct seq_file *m, int cpu);
1719 extern void print_rt_stats(struct seq_file *m, int cpu);
1720 extern void print_dl_stats(struct seq_file *m, int cpu);
1722 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
1724 #ifdef CONFIG_NUMA_BALANCING
1726 show_numa_stats(struct task_struct *p, struct seq_file *m);
1728 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
1729 unsigned long tpf, unsigned long gsf, unsigned long gpf);
1730 #endif /* CONFIG_NUMA_BALANCING */
1731 #endif /* CONFIG_SCHED_DEBUG */
1733 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
1734 extern void init_rt_rq(struct rt_rq *rt_rq);
1735 extern void init_dl_rq(struct dl_rq *dl_rq);
1737 extern void cfs_bandwidth_usage_inc(void);
1738 extern void cfs_bandwidth_usage_dec(void);
1740 #ifdef CONFIG_NO_HZ_COMMON
1741 enum rq_nohz_flag_bits {
1746 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
1749 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1751 DECLARE_PER_CPU(u64, cpu_hardirq_time);
1752 DECLARE_PER_CPU(u64, cpu_softirq_time);
1754 #ifndef CONFIG_64BIT
1755 DECLARE_PER_CPU(seqcount_t, irq_time_seq);
1757 static inline void irq_time_write_begin(void)
1759 __this_cpu_inc(irq_time_seq.sequence);
1763 static inline void irq_time_write_end(void)
1766 __this_cpu_inc(irq_time_seq.sequence);
1769 static inline u64 irq_time_read(int cpu)
1775 seq = read_seqcount_begin(&per_cpu(irq_time_seq, cpu));
1776 irq_time = per_cpu(cpu_softirq_time, cpu) +
1777 per_cpu(cpu_hardirq_time, cpu);
1778 } while (read_seqcount_retry(&per_cpu(irq_time_seq, cpu), seq));
1782 #else /* CONFIG_64BIT */
1783 static inline void irq_time_write_begin(void)
1787 static inline void irq_time_write_end(void)
1791 static inline u64 irq_time_read(int cpu)
1793 return per_cpu(cpu_softirq_time, cpu) + per_cpu(cpu_hardirq_time, cpu);
1795 #endif /* CONFIG_64BIT */
1796 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
1798 #ifdef CONFIG_CPU_FREQ
1799 DECLARE_PER_CPU(struct update_util_data *, cpufreq_update_util_data);
1802 * cpufreq_update_util - Take a note about CPU utilization changes.
1803 * @time: Current time.
1804 * @util: Current utilization.
1805 * @max: Utilization ceiling.
1807 * This function is called by the scheduler on every invocation of
1808 * update_load_avg() on the CPU whose utilization is being updated.
1810 * It can only be called from RCU-sched read-side critical sections.
1812 static inline void cpufreq_update_util(u64 time, unsigned long util, unsigned long max)
1814 struct update_util_data *data;
1816 data = rcu_dereference_sched(*this_cpu_ptr(&cpufreq_update_util_data));
1818 data->func(data, time, util, max);
1822 * cpufreq_trigger_update - Trigger CPU performance state evaluation if needed.
1823 * @time: Current time.
1825 * The way cpufreq is currently arranged requires it to evaluate the CPU
1826 * performance state (frequency/voltage) on a regular basis to prevent it from
1827 * being stuck in a completely inadequate performance level for too long.
1828 * That is not guaranteed to happen if the updates are only triggered from CFS,
1829 * though, because they may not be coming in if RT or deadline tasks are active
1830 * all the time (or there are RT and DL tasks only).
1832 * As a workaround for that issue, this function is called by the RT and DL
1833 * sched classes to trigger extra cpufreq updates to prevent it from stalling,
1834 * but that really is a band-aid. Going forward it should be replaced with
1835 * solutions targeted more specifically at RT and DL tasks.
1837 static inline void cpufreq_trigger_update(u64 time)
1839 cpufreq_update_util(time, ULONG_MAX, 0);
1842 static inline void cpufreq_update_util(u64 time, unsigned long util, unsigned long max) {}
1843 static inline void cpufreq_trigger_update(u64 time) {}
1844 #endif /* CONFIG_CPU_FREQ */
1846 static inline void account_reset_rq(struct rq *rq)
1848 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1849 rq->prev_irq_time = 0;
1851 #ifdef CONFIG_PARAVIRT
1852 rq->prev_steal_time = 0;
1854 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1855 rq->prev_steal_time_rq = 0;