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1
2#include <linux/sched.h>
3#include <linux/sched/sysctl.h>
4#include <linux/sched/rt.h>
5#include <linux/u64_stats_sync.h>
6#include <linux/sched/deadline.h>
7#include <linux/binfmts.h>
8#include <linux/mutex.h>
9#include <linux/spinlock.h>
10#include <linux/stop_machine.h>
11#include <linux/irq_work.h>
12#include <linux/tick.h>
13#include <linux/slab.h>
14
15#include "cpupri.h"
16#include "cpudeadline.h"
17#include "cpuacct.h"
18
19#ifdef CONFIG_SCHED_DEBUG
20#define SCHED_WARN_ON(x) WARN_ONCE(x, #x)
21#else
22#define SCHED_WARN_ON(x) ((void)(x))
23#endif
24
25struct rq;
26struct cpuidle_state;
27
28/* task_struct::on_rq states: */
29#define TASK_ON_RQ_QUEUED 1
30#define TASK_ON_RQ_MIGRATING 2
31
32extern __read_mostly int scheduler_running;
33
34extern unsigned long calc_load_update;
35extern atomic_long_t calc_load_tasks;
36
37extern void calc_global_load_tick(struct rq *this_rq);
38extern long calc_load_fold_active(struct rq *this_rq, long adjust);
39
40#ifdef CONFIG_SMP
41extern void cpu_load_update_active(struct rq *this_rq);
42#else
43static inline void cpu_load_update_active(struct rq *this_rq) { }
44#endif
45
46/*
47 * Helpers for converting nanosecond timing to jiffy resolution
48 */
49#define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
50
51/*
52 * Increase resolution of nice-level calculations for 64-bit architectures.
53 * The extra resolution improves shares distribution and load balancing of
54 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
55 * hierarchies, especially on larger systems. This is not a user-visible change
56 * and does not change the user-interface for setting shares/weights.
57 *
58 * We increase resolution only if we have enough bits to allow this increased
59 * resolution (i.e. 64bit). The costs for increasing resolution when 32bit are
60 * pretty high and the returns do not justify the increased costs.
61 *
62 * Really only required when CONFIG_FAIR_GROUP_SCHED is also set, but to
63 * increase coverage and consistency always enable it on 64bit platforms.
64 */
65#ifdef CONFIG_64BIT
66# define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
67# define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT)
68# define scale_load_down(w) ((w) >> SCHED_FIXEDPOINT_SHIFT)
69#else
70# define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT)
71# define scale_load(w) (w)
72# define scale_load_down(w) (w)
73#endif
74
75/*
76 * Task weight (visible to users) and its load (invisible to users) have
77 * independent resolution, but they should be well calibrated. We use
78 * scale_load() and scale_load_down(w) to convert between them. The
79 * following must be true:
80 *
81 * scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD
82 *
83 */
84#define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT)
85
86/*
87 * Single value that decides SCHED_DEADLINE internal math precision.
88 * 10 -> just above 1us
89 * 9 -> just above 0.5us
90 */
91#define DL_SCALE (10)
92
93/*
94 * These are the 'tuning knobs' of the scheduler:
95 */
96
97/*
98 * single value that denotes runtime == period, ie unlimited time.
99 */
100#define RUNTIME_INF ((u64)~0ULL)
101
102static inline int idle_policy(int policy)
103{
104 return policy == SCHED_IDLE;
105}
106static inline int fair_policy(int policy)
107{
108 return policy == SCHED_NORMAL || policy == SCHED_BATCH;
109}
110
111static inline int rt_policy(int policy)
112{
113 return policy == SCHED_FIFO || policy == SCHED_RR;
114}
115
116static inline int dl_policy(int policy)
117{
118 return policy == SCHED_DEADLINE;
119}
120static inline bool valid_policy(int policy)
121{
122 return idle_policy(policy) || fair_policy(policy) ||
123 rt_policy(policy) || dl_policy(policy);
124}
125
126static inline int task_has_rt_policy(struct task_struct *p)
127{
128 return rt_policy(p->policy);
129}
130
131static inline int task_has_dl_policy(struct task_struct *p)
132{
133 return dl_policy(p->policy);
134}
135
136/*
137 * Tells if entity @a should preempt entity @b.
138 */
139static inline bool
140dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
141{
142 return dl_time_before(a->deadline, b->deadline);
143}
144
145/*
146 * This is the priority-queue data structure of the RT scheduling class:
147 */
148struct rt_prio_array {
149 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
150 struct list_head queue[MAX_RT_PRIO];
151};
152
153struct rt_bandwidth {
154 /* nests inside the rq lock: */
155 raw_spinlock_t rt_runtime_lock;
156 ktime_t rt_period;
157 u64 rt_runtime;
158 struct hrtimer rt_period_timer;
159 unsigned int rt_period_active;
160};
161
162void __dl_clear_params(struct task_struct *p);
163
164/*
165 * To keep the bandwidth of -deadline tasks and groups under control
166 * we need some place where:
167 * - store the maximum -deadline bandwidth of the system (the group);
168 * - cache the fraction of that bandwidth that is currently allocated.
169 *
170 * This is all done in the data structure below. It is similar to the
171 * one used for RT-throttling (rt_bandwidth), with the main difference
172 * that, since here we are only interested in admission control, we
173 * do not decrease any runtime while the group "executes", neither we
174 * need a timer to replenish it.
175 *
176 * With respect to SMP, the bandwidth is given on a per-CPU basis,
177 * meaning that:
178 * - dl_bw (< 100%) is the bandwidth of the system (group) on each CPU;
179 * - dl_total_bw array contains, in the i-eth element, the currently
180 * allocated bandwidth on the i-eth CPU.
181 * Moreover, groups consume bandwidth on each CPU, while tasks only
182 * consume bandwidth on the CPU they're running on.
183 * Finally, dl_total_bw_cpu is used to cache the index of dl_total_bw
184 * that will be shown the next time the proc or cgroup controls will
185 * be red. It on its turn can be changed by writing on its own
186 * control.
187 */
188struct dl_bandwidth {
189 raw_spinlock_t dl_runtime_lock;
190 u64 dl_runtime;
191 u64 dl_period;
192};
193
194static inline int dl_bandwidth_enabled(void)
195{
196 return sysctl_sched_rt_runtime >= 0;
197}
198
199extern struct dl_bw *dl_bw_of(int i);
200
201struct dl_bw {
202 raw_spinlock_t lock;
203 u64 bw, total_bw;
204};
205
206static inline
207void __dl_clear(struct dl_bw *dl_b, u64 tsk_bw)
208{
209 dl_b->total_bw -= tsk_bw;
210}
211
212static inline
213void __dl_add(struct dl_bw *dl_b, u64 tsk_bw)
214{
215 dl_b->total_bw += tsk_bw;
216}
217
218static inline
219bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw)
220{
221 return dl_b->bw != -1 &&
222 dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw;
223}
224
225extern struct mutex sched_domains_mutex;
226
227#ifdef CONFIG_CGROUP_SCHED
228
229#include <linux/cgroup.h>
230
231struct cfs_rq;
232struct rt_rq;
233
234extern struct list_head task_groups;
235
236struct cfs_bandwidth {
237#ifdef CONFIG_CFS_BANDWIDTH
238 raw_spinlock_t lock;
239 ktime_t period;
240 u64 quota, runtime;
241 s64 hierarchical_quota;
242 u64 runtime_expires;
243
244 int idle, period_active;
245 struct hrtimer period_timer, slack_timer;
246 struct list_head throttled_cfs_rq;
247
248 /* statistics */
249 int nr_periods, nr_throttled;
250 u64 throttled_time;
251#endif
252};
253
254/* task group related information */
255struct task_group {
256 struct cgroup_subsys_state css;
257
258#ifdef CONFIG_FAIR_GROUP_SCHED
259 /* schedulable entities of this group on each cpu */
260 struct sched_entity **se;
261 /* runqueue "owned" by this group on each cpu */
262 struct cfs_rq **cfs_rq;
263 unsigned long shares;
264
265#ifdef CONFIG_SMP
266 /*
267 * load_avg can be heavily contended at clock tick time, so put
268 * it in its own cacheline separated from the fields above which
269 * will also be accessed at each tick.
270 */
271 atomic_long_t load_avg ____cacheline_aligned;
272#endif
273#endif
274
275#ifdef CONFIG_RT_GROUP_SCHED
276 struct sched_rt_entity **rt_se;
277 struct rt_rq **rt_rq;
278
279 struct rt_bandwidth rt_bandwidth;
280#endif
281
282 struct rcu_head rcu;
283 struct list_head list;
284
285 struct task_group *parent;
286 struct list_head siblings;
287 struct list_head children;
288
289#ifdef CONFIG_SCHED_AUTOGROUP
290 struct autogroup *autogroup;
291#endif
292
293 struct cfs_bandwidth cfs_bandwidth;
294};
295
296#ifdef CONFIG_FAIR_GROUP_SCHED
297#define ROOT_TASK_GROUP_LOAD NICE_0_LOAD
298
299/*
300 * A weight of 0 or 1 can cause arithmetics problems.
301 * A weight of a cfs_rq is the sum of weights of which entities
302 * are queued on this cfs_rq, so a weight of a entity should not be
303 * too large, so as the shares value of a task group.
304 * (The default weight is 1024 - so there's no practical
305 * limitation from this.)
306 */
307#define MIN_SHARES (1UL << 1)
308#define MAX_SHARES (1UL << 18)
309#endif
310
311typedef int (*tg_visitor)(struct task_group *, void *);
312
313extern int walk_tg_tree_from(struct task_group *from,
314 tg_visitor down, tg_visitor up, void *data);
315
316/*
317 * Iterate the full tree, calling @down when first entering a node and @up when
318 * leaving it for the final time.
319 *
320 * Caller must hold rcu_lock or sufficient equivalent.
321 */
322static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
323{
324 return walk_tg_tree_from(&root_task_group, down, up, data);
325}
326
327extern int tg_nop(struct task_group *tg, void *data);
328
329extern void free_fair_sched_group(struct task_group *tg);
330extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
331extern void online_fair_sched_group(struct task_group *tg);
332extern void unregister_fair_sched_group(struct task_group *tg);
333extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
334 struct sched_entity *se, int cpu,
335 struct sched_entity *parent);
336extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
337
338extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
339extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
340extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
341
342extern void free_rt_sched_group(struct task_group *tg);
343extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
344extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
345 struct sched_rt_entity *rt_se, int cpu,
346 struct sched_rt_entity *parent);
347
348extern struct task_group *sched_create_group(struct task_group *parent);
349extern void sched_online_group(struct task_group *tg,
350 struct task_group *parent);
351extern void sched_destroy_group(struct task_group *tg);
352extern void sched_offline_group(struct task_group *tg);
353
354extern void sched_move_task(struct task_struct *tsk);
355
356#ifdef CONFIG_FAIR_GROUP_SCHED
357extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
358
359#ifdef CONFIG_SMP
360extern void set_task_rq_fair(struct sched_entity *se,
361 struct cfs_rq *prev, struct cfs_rq *next);
362#else /* !CONFIG_SMP */
363static inline void set_task_rq_fair(struct sched_entity *se,
364 struct cfs_rq *prev, struct cfs_rq *next) { }
365#endif /* CONFIG_SMP */
366#endif /* CONFIG_FAIR_GROUP_SCHED */
367
368#else /* CONFIG_CGROUP_SCHED */
369
370struct cfs_bandwidth { };
371
372#endif /* CONFIG_CGROUP_SCHED */
373
374/* CFS-related fields in a runqueue */
375struct cfs_rq {
376 struct load_weight load;
377 unsigned int nr_running, h_nr_running;
378
379 u64 exec_clock;
380 u64 min_vruntime;
381#ifndef CONFIG_64BIT
382 u64 min_vruntime_copy;
383#endif
384
385 struct rb_root tasks_timeline;
386 struct rb_node *rb_leftmost;
387
388 /*
389 * 'curr' points to currently running entity on this cfs_rq.
390 * It is set to NULL otherwise (i.e when none are currently running).
391 */
392 struct sched_entity *curr, *next, *last, *skip;
393
394#ifdef CONFIG_SCHED_DEBUG
395 unsigned int nr_spread_over;
396#endif
397
398#ifdef CONFIG_SMP
399 /*
400 * CFS load tracking
401 */
402 struct sched_avg avg;
403 u64 runnable_load_sum;
404 unsigned long runnable_load_avg;
405#ifdef CONFIG_FAIR_GROUP_SCHED
406 unsigned long tg_load_avg_contrib;
407 unsigned long propagate_avg;
408#endif
409 atomic_long_t removed_load_avg, removed_util_avg;
410#ifndef CONFIG_64BIT
411 u64 load_last_update_time_copy;
412#endif
413
414#ifdef CONFIG_FAIR_GROUP_SCHED
415 /*
416 * h_load = weight * f(tg)
417 *
418 * Where f(tg) is the recursive weight fraction assigned to
419 * this group.
420 */
421 unsigned long h_load;
422 u64 last_h_load_update;
423 struct sched_entity *h_load_next;
424#endif /* CONFIG_FAIR_GROUP_SCHED */
425#endif /* CONFIG_SMP */
426
427#ifdef CONFIG_FAIR_GROUP_SCHED
428 struct rq *rq; /* cpu runqueue to which this cfs_rq is attached */
429
430 /*
431 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
432 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
433 * (like users, containers etc.)
434 *
435 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This
436 * list is used during load balance.
437 */
438 int on_list;
439 struct list_head leaf_cfs_rq_list;
440 struct task_group *tg; /* group that "owns" this runqueue */
441
442#ifdef CONFIG_CFS_BANDWIDTH
443 int runtime_enabled;
444 u64 runtime_expires;
445 s64 runtime_remaining;
446
447 u64 throttled_clock, throttled_clock_task;
448 u64 throttled_clock_task_time;
449 int throttled, throttle_count;
450 struct list_head throttled_list;
451#endif /* CONFIG_CFS_BANDWIDTH */
452#endif /* CONFIG_FAIR_GROUP_SCHED */
453};
454
455static inline int rt_bandwidth_enabled(void)
456{
457 return sysctl_sched_rt_runtime >= 0;
458}
459
460/* RT IPI pull logic requires IRQ_WORK */
461#ifdef CONFIG_IRQ_WORK
462# define HAVE_RT_PUSH_IPI
463#endif
464
465/* Real-Time classes' related field in a runqueue: */
466struct rt_rq {
467 struct rt_prio_array active;
468 unsigned int rt_nr_running;
469 unsigned int rr_nr_running;
470#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
471 struct {
472 int curr; /* highest queued rt task prio */
473#ifdef CONFIG_SMP
474 int next; /* next highest */
475#endif
476 } highest_prio;
477#endif
478#ifdef CONFIG_SMP
479 unsigned long rt_nr_migratory;
480 unsigned long rt_nr_total;
481 int overloaded;
482 struct plist_head pushable_tasks;
483#ifdef HAVE_RT_PUSH_IPI
484 int push_flags;
485 int push_cpu;
486 struct irq_work push_work;
487 raw_spinlock_t push_lock;
488#endif
489#endif /* CONFIG_SMP */
490 int rt_queued;
491
492 int rt_throttled;
493 u64 rt_time;
494 u64 rt_runtime;
495 /* Nests inside the rq lock: */
496 raw_spinlock_t rt_runtime_lock;
497
498#ifdef CONFIG_RT_GROUP_SCHED
499 unsigned long rt_nr_boosted;
500
501 struct rq *rq;
502 struct task_group *tg;
503#endif
504};
505
506/* Deadline class' related fields in a runqueue */
507struct dl_rq {
508 /* runqueue is an rbtree, ordered by deadline */
509 struct rb_root rb_root;
510 struct rb_node *rb_leftmost;
511
512 unsigned long dl_nr_running;
513
514#ifdef CONFIG_SMP
515 /*
516 * Deadline values of the currently executing and the
517 * earliest ready task on this rq. Caching these facilitates
518 * the decision wether or not a ready but not running task
519 * should migrate somewhere else.
520 */
521 struct {
522 u64 curr;
523 u64 next;
524 } earliest_dl;
525
526 unsigned long dl_nr_migratory;
527 int overloaded;
528
529 /*
530 * Tasks on this rq that can be pushed away. They are kept in
531 * an rb-tree, ordered by tasks' deadlines, with caching
532 * of the leftmost (earliest deadline) element.
533 */
534 struct rb_root pushable_dl_tasks_root;
535 struct rb_node *pushable_dl_tasks_leftmost;
536#else
537 struct dl_bw dl_bw;
538#endif
539};
540
541#ifdef CONFIG_SMP
542
543static inline bool sched_asym_prefer(int a, int b)
544{
545 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
546}
547
548/*
549 * We add the notion of a root-domain which will be used to define per-domain
550 * variables. Each exclusive cpuset essentially defines an island domain by
551 * fully partitioning the member cpus from any other cpuset. Whenever a new
552 * exclusive cpuset is created, we also create and attach a new root-domain
553 * object.
554 *
555 */
556struct root_domain {
557 atomic_t refcount;
558 atomic_t rto_count;
559 struct rcu_head rcu;
560 cpumask_var_t span;
561 cpumask_var_t online;
562
563 /* Indicate more than one runnable task for any CPU */
564 bool overload;
565
566 /*
567 * The bit corresponding to a CPU gets set here if such CPU has more
568 * than one runnable -deadline task (as it is below for RT tasks).
569 */
570 cpumask_var_t dlo_mask;
571 atomic_t dlo_count;
572 struct dl_bw dl_bw;
573 struct cpudl cpudl;
574
575 /*
576 * The "RT overload" flag: it gets set if a CPU has more than
577 * one runnable RT task.
578 */
579 cpumask_var_t rto_mask;
580 struct cpupri cpupri;
581
582 unsigned long max_cpu_capacity;
583};
584
585extern struct root_domain def_root_domain;
586
587#endif /* CONFIG_SMP */
588
589/*
590 * This is the main, per-CPU runqueue data structure.
591 *
592 * Locking rule: those places that want to lock multiple runqueues
593 * (such as the load balancing or the thread migration code), lock
594 * acquire operations must be ordered by ascending &runqueue.
595 */
596struct rq {
597 /* runqueue lock: */
598 raw_spinlock_t lock;
599
600 /*
601 * nr_running and cpu_load should be in the same cacheline because
602 * remote CPUs use both these fields when doing load calculation.
603 */
604 unsigned int nr_running;
605#ifdef CONFIG_NUMA_BALANCING
606 unsigned int nr_numa_running;
607 unsigned int nr_preferred_running;
608#endif
609 #define CPU_LOAD_IDX_MAX 5
610 unsigned long cpu_load[CPU_LOAD_IDX_MAX];
611#ifdef CONFIG_NO_HZ_COMMON
612#ifdef CONFIG_SMP
613 unsigned long last_load_update_tick;
614#endif /* CONFIG_SMP */
615 unsigned long nohz_flags;
616#endif /* CONFIG_NO_HZ_COMMON */
617#ifdef CONFIG_NO_HZ_FULL
618 unsigned long last_sched_tick;
619#endif
620 /* capture load from *all* tasks on this cpu: */
621 struct load_weight load;
622 unsigned long nr_load_updates;
623 u64 nr_switches;
624
625 struct cfs_rq cfs;
626 struct rt_rq rt;
627 struct dl_rq dl;
628
629#ifdef CONFIG_FAIR_GROUP_SCHED
630 /* list of leaf cfs_rq on this cpu: */
631 struct list_head leaf_cfs_rq_list;
632 struct list_head *tmp_alone_branch;
633#endif /* CONFIG_FAIR_GROUP_SCHED */
634
635 /*
636 * This is part of a global counter where only the total sum
637 * over all CPUs matters. A task can increase this counter on
638 * one CPU and if it got migrated afterwards it may decrease
639 * it on another CPU. Always updated under the runqueue lock:
640 */
641 unsigned long nr_uninterruptible;
642
643 struct task_struct *curr, *idle, *stop;
644 unsigned long next_balance;
645 struct mm_struct *prev_mm;
646
647 unsigned int clock_skip_update;
648 u64 clock;
649 u64 clock_task;
650
651 atomic_t nr_iowait;
652
653#ifdef CONFIG_SMP
654 struct root_domain *rd;
655 struct sched_domain *sd;
656
657 unsigned long cpu_capacity;
658 unsigned long cpu_capacity_orig;
659
660 struct callback_head *balance_callback;
661
662 unsigned char idle_balance;
663 /* For active balancing */
664 int active_balance;
665 int push_cpu;
666 struct cpu_stop_work active_balance_work;
667 /* cpu of this runqueue: */
668 int cpu;
669 int online;
670
671 struct list_head cfs_tasks;
672
673 u64 rt_avg;
674 u64 age_stamp;
675 u64 idle_stamp;
676 u64 avg_idle;
677
678 /* This is used to determine avg_idle's max value */
679 u64 max_idle_balance_cost;
680#endif
681
682#ifdef CONFIG_IRQ_TIME_ACCOUNTING
683 u64 prev_irq_time;
684#endif
685#ifdef CONFIG_PARAVIRT
686 u64 prev_steal_time;
687#endif
688#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
689 u64 prev_steal_time_rq;
690#endif
691
692 /* calc_load related fields */
693 unsigned long calc_load_update;
694 long calc_load_active;
695
696#ifdef CONFIG_SCHED_HRTICK
697#ifdef CONFIG_SMP
698 int hrtick_csd_pending;
699 struct call_single_data hrtick_csd;
700#endif
701 struct hrtimer hrtick_timer;
702#endif
703
704#ifdef CONFIG_SCHEDSTATS
705 /* latency stats */
706 struct sched_info rq_sched_info;
707 unsigned long long rq_cpu_time;
708 /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
709
710 /* sys_sched_yield() stats */
711 unsigned int yld_count;
712
713 /* schedule() stats */
714 unsigned int sched_count;
715 unsigned int sched_goidle;
716
717 /* try_to_wake_up() stats */
718 unsigned int ttwu_count;
719 unsigned int ttwu_local;
720#endif
721
722#ifdef CONFIG_SMP
723 struct llist_head wake_list;
724#endif
725
726#ifdef CONFIG_CPU_IDLE
727 /* Must be inspected within a rcu lock section */
728 struct cpuidle_state *idle_state;
729#endif
730};
731
732static inline int cpu_of(struct rq *rq)
733{
734#ifdef CONFIG_SMP
735 return rq->cpu;
736#else
737 return 0;
738#endif
739}
740
741
742#ifdef CONFIG_SCHED_SMT
743
744extern struct static_key_false sched_smt_present;
745
746extern void __update_idle_core(struct rq *rq);
747
748static inline void update_idle_core(struct rq *rq)
749{
750 if (static_branch_unlikely(&sched_smt_present))
751 __update_idle_core(rq);
752}
753
754#else
755static inline void update_idle_core(struct rq *rq) { }
756#endif
757
758DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
759
760#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
761#define this_rq() this_cpu_ptr(&runqueues)
762#define task_rq(p) cpu_rq(task_cpu(p))
763#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
764#define raw_rq() raw_cpu_ptr(&runqueues)
765
766static inline u64 __rq_clock_broken(struct rq *rq)
767{
768 return READ_ONCE(rq->clock);
769}
770
771static inline u64 rq_clock(struct rq *rq)
772{
773 lockdep_assert_held(&rq->lock);
774 return rq->clock;
775}
776
777static inline u64 rq_clock_task(struct rq *rq)
778{
779 lockdep_assert_held(&rq->lock);
780 return rq->clock_task;
781}
782
783#define RQCF_REQ_SKIP 0x01
784#define RQCF_ACT_SKIP 0x02
785
786static inline void rq_clock_skip_update(struct rq *rq, bool skip)
787{
788 lockdep_assert_held(&rq->lock);
789 if (skip)
790 rq->clock_skip_update |= RQCF_REQ_SKIP;
791 else
792 rq->clock_skip_update &= ~RQCF_REQ_SKIP;
793}
794
795#ifdef CONFIG_NUMA
796enum numa_topology_type {
797 NUMA_DIRECT,
798 NUMA_GLUELESS_MESH,
799 NUMA_BACKPLANE,
800};
801extern enum numa_topology_type sched_numa_topology_type;
802extern int sched_max_numa_distance;
803extern bool find_numa_distance(int distance);
804#endif
805
806#ifdef CONFIG_NUMA_BALANCING
807/* The regions in numa_faults array from task_struct */
808enum numa_faults_stats {
809 NUMA_MEM = 0,
810 NUMA_CPU,
811 NUMA_MEMBUF,
812 NUMA_CPUBUF
813};
814extern void sched_setnuma(struct task_struct *p, int node);
815extern int migrate_task_to(struct task_struct *p, int cpu);
816extern int migrate_swap(struct task_struct *, struct task_struct *);
817#endif /* CONFIG_NUMA_BALANCING */
818
819#ifdef CONFIG_SMP
820
821static inline void
822queue_balance_callback(struct rq *rq,
823 struct callback_head *head,
824 void (*func)(struct rq *rq))
825{
826 lockdep_assert_held(&rq->lock);
827
828 if (unlikely(head->next))
829 return;
830
831 head->func = (void (*)(struct callback_head *))func;
832 head->next = rq->balance_callback;
833 rq->balance_callback = head;
834}
835
836extern void sched_ttwu_pending(void);
837
838#define rcu_dereference_check_sched_domain(p) \
839 rcu_dereference_check((p), \
840 lockdep_is_held(&sched_domains_mutex))
841
842/*
843 * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
844 * See detach_destroy_domains: synchronize_sched for details.
845 *
846 * The domain tree of any CPU may only be accessed from within
847 * preempt-disabled sections.
848 */
849#define for_each_domain(cpu, __sd) \
850 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
851 __sd; __sd = __sd->parent)
852
853#define for_each_lower_domain(sd) for (; sd; sd = sd->child)
854
855/**
856 * highest_flag_domain - Return highest sched_domain containing flag.
857 * @cpu: The cpu whose highest level of sched domain is to
858 * be returned.
859 * @flag: The flag to check for the highest sched_domain
860 * for the given cpu.
861 *
862 * Returns the highest sched_domain of a cpu which contains the given flag.
863 */
864static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
865{
866 struct sched_domain *sd, *hsd = NULL;
867
868 for_each_domain(cpu, sd) {
869 if (!(sd->flags & flag))
870 break;
871 hsd = sd;
872 }
873
874 return hsd;
875}
876
877static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
878{
879 struct sched_domain *sd;
880
881 for_each_domain(cpu, sd) {
882 if (sd->flags & flag)
883 break;
884 }
885
886 return sd;
887}
888
889DECLARE_PER_CPU(struct sched_domain *, sd_llc);
890DECLARE_PER_CPU(int, sd_llc_size);
891DECLARE_PER_CPU(int, sd_llc_id);
892DECLARE_PER_CPU(struct sched_domain_shared *, sd_llc_shared);
893DECLARE_PER_CPU(struct sched_domain *, sd_numa);
894DECLARE_PER_CPU(struct sched_domain *, sd_asym);
895
896struct sched_group_capacity {
897 atomic_t ref;
898 /*
899 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
900 * for a single CPU.
901 */
902 unsigned long capacity;
903 unsigned long min_capacity; /* Min per-CPU capacity in group */
904 unsigned long next_update;
905 int imbalance; /* XXX unrelated to capacity but shared group state */
906
907 unsigned long cpumask[0]; /* iteration mask */
908};
909
910struct sched_group {
911 struct sched_group *next; /* Must be a circular list */
912 atomic_t ref;
913
914 unsigned int group_weight;
915 struct sched_group_capacity *sgc;
916 int asym_prefer_cpu; /* cpu of highest priority in group */
917
918 /*
919 * The CPUs this group covers.
920 *
921 * NOTE: this field is variable length. (Allocated dynamically
922 * by attaching extra space to the end of the structure,
923 * depending on how many CPUs the kernel has booted up with)
924 */
925 unsigned long cpumask[0];
926};
927
928static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
929{
930 return to_cpumask(sg->cpumask);
931}
932
933/*
934 * cpumask masking which cpus in the group are allowed to iterate up the domain
935 * tree.
936 */
937static inline struct cpumask *sched_group_mask(struct sched_group *sg)
938{
939 return to_cpumask(sg->sgc->cpumask);
940}
941
942/**
943 * group_first_cpu - Returns the first cpu in the cpumask of a sched_group.
944 * @group: The group whose first cpu is to be returned.
945 */
946static inline unsigned int group_first_cpu(struct sched_group *group)
947{
948 return cpumask_first(sched_group_cpus(group));
949}
950
951extern int group_balance_cpu(struct sched_group *sg);
952
953#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
954void register_sched_domain_sysctl(void);
955void unregister_sched_domain_sysctl(void);
956#else
957static inline void register_sched_domain_sysctl(void)
958{
959}
960static inline void unregister_sched_domain_sysctl(void)
961{
962}
963#endif
964
965#else
966
967static inline void sched_ttwu_pending(void) { }
968
969#endif /* CONFIG_SMP */
970
971#include "stats.h"
972#include "auto_group.h"
973
974#ifdef CONFIG_CGROUP_SCHED
975
976/*
977 * Return the group to which this tasks belongs.
978 *
979 * We cannot use task_css() and friends because the cgroup subsystem
980 * changes that value before the cgroup_subsys::attach() method is called,
981 * therefore we cannot pin it and might observe the wrong value.
982 *
983 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
984 * core changes this before calling sched_move_task().
985 *
986 * Instead we use a 'copy' which is updated from sched_move_task() while
987 * holding both task_struct::pi_lock and rq::lock.
988 */
989static inline struct task_group *task_group(struct task_struct *p)
990{
991 return p->sched_task_group;
992}
993
994/* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
995static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
996{
997#if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
998 struct task_group *tg = task_group(p);
999#endif
1000
1001#ifdef CONFIG_FAIR_GROUP_SCHED
1002 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
1003 p->se.cfs_rq = tg->cfs_rq[cpu];
1004 p->se.parent = tg->se[cpu];
1005#endif
1006
1007#ifdef CONFIG_RT_GROUP_SCHED
1008 p->rt.rt_rq = tg->rt_rq[cpu];
1009 p->rt.parent = tg->rt_se[cpu];
1010#endif
1011}
1012
1013#else /* CONFIG_CGROUP_SCHED */
1014
1015static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
1016static inline struct task_group *task_group(struct task_struct *p)
1017{
1018 return NULL;
1019}
1020
1021#endif /* CONFIG_CGROUP_SCHED */
1022
1023static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
1024{
1025 set_task_rq(p, cpu);
1026#ifdef CONFIG_SMP
1027 /*
1028 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
1029 * successfuly executed on another CPU. We must ensure that updates of
1030 * per-task data have been completed by this moment.
1031 */
1032 smp_wmb();
1033#ifdef CONFIG_THREAD_INFO_IN_TASK
1034 p->cpu = cpu;
1035#else
1036 task_thread_info(p)->cpu = cpu;
1037#endif
1038 p->wake_cpu = cpu;
1039#endif
1040}
1041
1042/*
1043 * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
1044 */
1045#ifdef CONFIG_SCHED_DEBUG
1046# include <linux/static_key.h>
1047# define const_debug __read_mostly
1048#else
1049# define const_debug const
1050#endif
1051
1052extern const_debug unsigned int sysctl_sched_features;
1053
1054#define SCHED_FEAT(name, enabled) \
1055 __SCHED_FEAT_##name ,
1056
1057enum {
1058#include "features.h"
1059 __SCHED_FEAT_NR,
1060};
1061
1062#undef SCHED_FEAT
1063
1064#if defined(CONFIG_SCHED_DEBUG) && defined(HAVE_JUMP_LABEL)
1065#define SCHED_FEAT(name, enabled) \
1066static __always_inline bool static_branch_##name(struct static_key *key) \
1067{ \
1068 return static_key_##enabled(key); \
1069}
1070
1071#include "features.h"
1072
1073#undef SCHED_FEAT
1074
1075extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
1076#define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
1077#else /* !(SCHED_DEBUG && HAVE_JUMP_LABEL) */
1078#define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1079#endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */
1080
1081extern struct static_key_false sched_numa_balancing;
1082extern struct static_key_false sched_schedstats;
1083
1084static inline u64 global_rt_period(void)
1085{
1086 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
1087}
1088
1089static inline u64 global_rt_runtime(void)
1090{
1091 if (sysctl_sched_rt_runtime < 0)
1092 return RUNTIME_INF;
1093
1094 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
1095}
1096
1097static inline int task_current(struct rq *rq, struct task_struct *p)
1098{
1099 return rq->curr == p;
1100}
1101
1102static inline int task_running(struct rq *rq, struct task_struct *p)
1103{
1104#ifdef CONFIG_SMP
1105 return p->on_cpu;
1106#else
1107 return task_current(rq, p);
1108#endif
1109}
1110
1111static inline int task_on_rq_queued(struct task_struct *p)
1112{
1113 return p->on_rq == TASK_ON_RQ_QUEUED;
1114}
1115
1116static inline int task_on_rq_migrating(struct task_struct *p)
1117{
1118 return p->on_rq == TASK_ON_RQ_MIGRATING;
1119}
1120
1121#ifndef prepare_arch_switch
1122# define prepare_arch_switch(next) do { } while (0)
1123#endif
1124#ifndef finish_arch_post_lock_switch
1125# define finish_arch_post_lock_switch() do { } while (0)
1126#endif
1127
1128static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
1129{
1130#ifdef CONFIG_SMP
1131 /*
1132 * We can optimise this out completely for !SMP, because the
1133 * SMP rebalancing from interrupt is the only thing that cares
1134 * here.
1135 */
1136 next->on_cpu = 1;
1137#endif
1138}
1139
1140static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
1141{
1142#ifdef CONFIG_SMP
1143 /*
1144 * After ->on_cpu is cleared, the task can be moved to a different CPU.
1145 * We must ensure this doesn't happen until the switch is completely
1146 * finished.
1147 *
1148 * In particular, the load of prev->state in finish_task_switch() must
1149 * happen before this.
1150 *
1151 * Pairs with the smp_cond_load_acquire() in try_to_wake_up().
1152 */
1153 smp_store_release(&prev->on_cpu, 0);
1154#endif
1155#ifdef CONFIG_DEBUG_SPINLOCK
1156 /* this is a valid case when another task releases the spinlock */
1157 rq->lock.owner = current;
1158#endif
1159 /*
1160 * If we are tracking spinlock dependencies then we have to
1161 * fix up the runqueue lock - which gets 'carried over' from
1162 * prev into current:
1163 */
1164 spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_);
1165
1166 raw_spin_unlock_irq(&rq->lock);
1167}
1168
1169/*
1170 * wake flags
1171 */
1172#define WF_SYNC 0x01 /* waker goes to sleep after wakeup */
1173#define WF_FORK 0x02 /* child wakeup after fork */
1174#define WF_MIGRATED 0x4 /* internal use, task got migrated */
1175
1176/*
1177 * To aid in avoiding the subversion of "niceness" due to uneven distribution
1178 * of tasks with abnormal "nice" values across CPUs the contribution that
1179 * each task makes to its run queue's load is weighted according to its
1180 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
1181 * scaled version of the new time slice allocation that they receive on time
1182 * slice expiry etc.
1183 */
1184
1185#define WEIGHT_IDLEPRIO 3
1186#define WMULT_IDLEPRIO 1431655765
1187
1188extern const int sched_prio_to_weight[40];
1189extern const u32 sched_prio_to_wmult[40];
1190
1191/*
1192 * {de,en}queue flags:
1193 *
1194 * DEQUEUE_SLEEP - task is no longer runnable
1195 * ENQUEUE_WAKEUP - task just became runnable
1196 *
1197 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
1198 * are in a known state which allows modification. Such pairs
1199 * should preserve as much state as possible.
1200 *
1201 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
1202 * in the runqueue.
1203 *
1204 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified)
1205 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
1206 * ENQUEUE_MIGRATED - the task was migrated during wakeup
1207 *
1208 */
1209
1210#define DEQUEUE_SLEEP 0x01
1211#define DEQUEUE_SAVE 0x02 /* matches ENQUEUE_RESTORE */
1212#define DEQUEUE_MOVE 0x04 /* matches ENQUEUE_MOVE */
1213
1214#define ENQUEUE_WAKEUP 0x01
1215#define ENQUEUE_RESTORE 0x02
1216#define ENQUEUE_MOVE 0x04
1217
1218#define ENQUEUE_HEAD 0x08
1219#define ENQUEUE_REPLENISH 0x10
1220#ifdef CONFIG_SMP
1221#define ENQUEUE_MIGRATED 0x20
1222#else
1223#define ENQUEUE_MIGRATED 0x00
1224#endif
1225
1226#define RETRY_TASK ((void *)-1UL)
1227
1228struct sched_class {
1229 const struct sched_class *next;
1230
1231 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1232 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1233 void (*yield_task) (struct rq *rq);
1234 bool (*yield_to_task) (struct rq *rq, struct task_struct *p, bool preempt);
1235
1236 void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
1237
1238 /*
1239 * It is the responsibility of the pick_next_task() method that will
1240 * return the next task to call put_prev_task() on the @prev task or
1241 * something equivalent.
1242 *
1243 * May return RETRY_TASK when it finds a higher prio class has runnable
1244 * tasks.
1245 */
1246 struct task_struct * (*pick_next_task) (struct rq *rq,
1247 struct task_struct *prev,
1248 struct pin_cookie cookie);
1249 void (*put_prev_task) (struct rq *rq, struct task_struct *p);
1250
1251#ifdef CONFIG_SMP
1252 int (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
1253 void (*migrate_task_rq)(struct task_struct *p);
1254
1255 void (*task_woken) (struct rq *this_rq, struct task_struct *task);
1256
1257 void (*set_cpus_allowed)(struct task_struct *p,
1258 const struct cpumask *newmask);
1259
1260 void (*rq_online)(struct rq *rq);
1261 void (*rq_offline)(struct rq *rq);
1262#endif
1263
1264 void (*set_curr_task) (struct rq *rq);
1265 void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1266 void (*task_fork) (struct task_struct *p);
1267 void (*task_dead) (struct task_struct *p);
1268
1269 /*
1270 * The switched_from() call is allowed to drop rq->lock, therefore we
1271 * cannot assume the switched_from/switched_to pair is serliazed by
1272 * rq->lock. They are however serialized by p->pi_lock.
1273 */
1274 void (*switched_from) (struct rq *this_rq, struct task_struct *task);
1275 void (*switched_to) (struct rq *this_rq, struct task_struct *task);
1276 void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1277 int oldprio);
1278
1279 unsigned int (*get_rr_interval) (struct rq *rq,
1280 struct task_struct *task);
1281
1282 void (*update_curr) (struct rq *rq);
1283
1284#define TASK_SET_GROUP 0
1285#define TASK_MOVE_GROUP 1
1286
1287#ifdef CONFIG_FAIR_GROUP_SCHED
1288 void (*task_change_group) (struct task_struct *p, int type);
1289#endif
1290};
1291
1292static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
1293{
1294 prev->sched_class->put_prev_task(rq, prev);
1295}
1296
1297static inline void set_curr_task(struct rq *rq, struct task_struct *curr)
1298{
1299 curr->sched_class->set_curr_task(rq);
1300}
1301
1302#define sched_class_highest (&stop_sched_class)
1303#define for_each_class(class) \
1304 for (class = sched_class_highest; class; class = class->next)
1305
1306extern const struct sched_class stop_sched_class;
1307extern const struct sched_class dl_sched_class;
1308extern const struct sched_class rt_sched_class;
1309extern const struct sched_class fair_sched_class;
1310extern const struct sched_class idle_sched_class;
1311
1312
1313#ifdef CONFIG_SMP
1314
1315extern void update_group_capacity(struct sched_domain *sd, int cpu);
1316
1317extern void trigger_load_balance(struct rq *rq);
1318
1319extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask);
1320
1321#endif
1322
1323#ifdef CONFIG_CPU_IDLE
1324static inline void idle_set_state(struct rq *rq,
1325 struct cpuidle_state *idle_state)
1326{
1327 rq->idle_state = idle_state;
1328}
1329
1330static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1331{
1332 SCHED_WARN_ON(!rcu_read_lock_held());
1333 return rq->idle_state;
1334}
1335#else
1336static inline void idle_set_state(struct rq *rq,
1337 struct cpuidle_state *idle_state)
1338{
1339}
1340
1341static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1342{
1343 return NULL;
1344}
1345#endif
1346
1347extern void sysrq_sched_debug_show(void);
1348extern void sched_init_granularity(void);
1349extern void update_max_interval(void);
1350
1351extern void init_sched_dl_class(void);
1352extern void init_sched_rt_class(void);
1353extern void init_sched_fair_class(void);
1354
1355extern void resched_curr(struct rq *rq);
1356extern void resched_cpu(int cpu);
1357
1358extern struct rt_bandwidth def_rt_bandwidth;
1359extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
1360
1361extern struct dl_bandwidth def_dl_bandwidth;
1362extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
1363extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
1364
1365unsigned long to_ratio(u64 period, u64 runtime);
1366
1367extern void init_entity_runnable_average(struct sched_entity *se);
1368extern void post_init_entity_util_avg(struct sched_entity *se);
1369
1370#ifdef CONFIG_NO_HZ_FULL
1371extern bool sched_can_stop_tick(struct rq *rq);
1372
1373/*
1374 * Tick may be needed by tasks in the runqueue depending on their policy and
1375 * requirements. If tick is needed, lets send the target an IPI to kick it out of
1376 * nohz mode if necessary.
1377 */
1378static inline void sched_update_tick_dependency(struct rq *rq)
1379{
1380 int cpu;
1381
1382 if (!tick_nohz_full_enabled())
1383 return;
1384
1385 cpu = cpu_of(rq);
1386
1387 if (!tick_nohz_full_cpu(cpu))
1388 return;
1389
1390 if (sched_can_stop_tick(rq))
1391 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
1392 else
1393 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
1394}
1395#else
1396static inline void sched_update_tick_dependency(struct rq *rq) { }
1397#endif
1398
1399static inline void add_nr_running(struct rq *rq, unsigned count)
1400{
1401 unsigned prev_nr = rq->nr_running;
1402
1403 rq->nr_running = prev_nr + count;
1404
1405 if (prev_nr < 2 && rq->nr_running >= 2) {
1406#ifdef CONFIG_SMP
1407 if (!rq->rd->overload)
1408 rq->rd->overload = true;
1409#endif
1410 }
1411
1412 sched_update_tick_dependency(rq);
1413}
1414
1415static inline void sub_nr_running(struct rq *rq, unsigned count)
1416{
1417 rq->nr_running -= count;
1418 /* Check if we still need preemption */
1419 sched_update_tick_dependency(rq);
1420}
1421
1422static inline void rq_last_tick_reset(struct rq *rq)
1423{
1424#ifdef CONFIG_NO_HZ_FULL
1425 rq->last_sched_tick = jiffies;
1426#endif
1427}
1428
1429extern void update_rq_clock(struct rq *rq);
1430
1431extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
1432extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
1433
1434extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
1435
1436extern const_debug unsigned int sysctl_sched_time_avg;
1437extern const_debug unsigned int sysctl_sched_nr_migrate;
1438extern const_debug unsigned int sysctl_sched_migration_cost;
1439
1440static inline u64 sched_avg_period(void)
1441{
1442 return (u64)sysctl_sched_time_avg * NSEC_PER_MSEC / 2;
1443}
1444
1445#ifdef CONFIG_SCHED_HRTICK
1446
1447/*
1448 * Use hrtick when:
1449 * - enabled by features
1450 * - hrtimer is actually high res
1451 */
1452static inline int hrtick_enabled(struct rq *rq)
1453{
1454 if (!sched_feat(HRTICK))
1455 return 0;
1456 if (!cpu_active(cpu_of(rq)))
1457 return 0;
1458 return hrtimer_is_hres_active(&rq->hrtick_timer);
1459}
1460
1461void hrtick_start(struct rq *rq, u64 delay);
1462
1463#else
1464
1465static inline int hrtick_enabled(struct rq *rq)
1466{
1467 return 0;
1468}
1469
1470#endif /* CONFIG_SCHED_HRTICK */
1471
1472#ifdef CONFIG_SMP
1473extern void sched_avg_update(struct rq *rq);
1474
1475#ifndef arch_scale_freq_capacity
1476static __always_inline
1477unsigned long arch_scale_freq_capacity(struct sched_domain *sd, int cpu)
1478{
1479 return SCHED_CAPACITY_SCALE;
1480}
1481#endif
1482
1483#ifndef arch_scale_cpu_capacity
1484static __always_inline
1485unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu)
1486{
1487 if (sd && (sd->flags & SD_SHARE_CPUCAPACITY) && (sd->span_weight > 1))
1488 return sd->smt_gain / sd->span_weight;
1489
1490 return SCHED_CAPACITY_SCALE;
1491}
1492#endif
1493
1494static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
1495{
1496 rq->rt_avg += rt_delta * arch_scale_freq_capacity(NULL, cpu_of(rq));
1497 sched_avg_update(rq);
1498}
1499#else
1500static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { }
1501static inline void sched_avg_update(struct rq *rq) { }
1502#endif
1503
1504struct rq_flags {
1505 unsigned long flags;
1506 struct pin_cookie cookie;
1507};
1508
1509struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1510 __acquires(rq->lock);
1511struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1512 __acquires(p->pi_lock)
1513 __acquires(rq->lock);
1514
1515static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1516 __releases(rq->lock)
1517{
1518 lockdep_unpin_lock(&rq->lock, rf->cookie);
1519 raw_spin_unlock(&rq->lock);
1520}
1521
1522static inline void
1523task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1524 __releases(rq->lock)
1525 __releases(p->pi_lock)
1526{
1527 lockdep_unpin_lock(&rq->lock, rf->cookie);
1528 raw_spin_unlock(&rq->lock);
1529 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1530}
1531
1532#ifdef CONFIG_SMP
1533#ifdef CONFIG_PREEMPT
1534
1535static inline void double_rq_lock(struct rq *rq1, struct rq *rq2);
1536
1537/*
1538 * fair double_lock_balance: Safely acquires both rq->locks in a fair
1539 * way at the expense of forcing extra atomic operations in all
1540 * invocations. This assures that the double_lock is acquired using the
1541 * same underlying policy as the spinlock_t on this architecture, which
1542 * reduces latency compared to the unfair variant below. However, it
1543 * also adds more overhead and therefore may reduce throughput.
1544 */
1545static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1546 __releases(this_rq->lock)
1547 __acquires(busiest->lock)
1548 __acquires(this_rq->lock)
1549{
1550 raw_spin_unlock(&this_rq->lock);
1551 double_rq_lock(this_rq, busiest);
1552
1553 return 1;
1554}
1555
1556#else
1557/*
1558 * Unfair double_lock_balance: Optimizes throughput at the expense of
1559 * latency by eliminating extra atomic operations when the locks are
1560 * already in proper order on entry. This favors lower cpu-ids and will
1561 * grant the double lock to lower cpus over higher ids under contention,
1562 * regardless of entry order into the function.
1563 */
1564static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1565 __releases(this_rq->lock)
1566 __acquires(busiest->lock)
1567 __acquires(this_rq->lock)
1568{
1569 int ret = 0;
1570
1571 if (unlikely(!raw_spin_trylock(&busiest->lock))) {
1572 if (busiest < this_rq) {
1573 raw_spin_unlock(&this_rq->lock);
1574 raw_spin_lock(&busiest->lock);
1575 raw_spin_lock_nested(&this_rq->lock,
1576 SINGLE_DEPTH_NESTING);
1577 ret = 1;
1578 } else
1579 raw_spin_lock_nested(&busiest->lock,
1580 SINGLE_DEPTH_NESTING);
1581 }
1582 return ret;
1583}
1584
1585#endif /* CONFIG_PREEMPT */
1586
1587/*
1588 * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
1589 */
1590static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
1591{
1592 if (unlikely(!irqs_disabled())) {
1593 /* printk() doesn't work good under rq->lock */
1594 raw_spin_unlock(&this_rq->lock);
1595 BUG_ON(1);
1596 }
1597
1598 return _double_lock_balance(this_rq, busiest);
1599}
1600
1601static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
1602 __releases(busiest->lock)
1603{
1604 raw_spin_unlock(&busiest->lock);
1605 lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
1606}
1607
1608static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
1609{
1610 if (l1 > l2)
1611 swap(l1, l2);
1612
1613 spin_lock(l1);
1614 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1615}
1616
1617static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
1618{
1619 if (l1 > l2)
1620 swap(l1, l2);
1621
1622 spin_lock_irq(l1);
1623 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1624}
1625
1626static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
1627{
1628 if (l1 > l2)
1629 swap(l1, l2);
1630
1631 raw_spin_lock(l1);
1632 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1633}
1634
1635/*
1636 * double_rq_lock - safely lock two runqueues
1637 *
1638 * Note this does not disable interrupts like task_rq_lock,
1639 * you need to do so manually before calling.
1640 */
1641static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
1642 __acquires(rq1->lock)
1643 __acquires(rq2->lock)
1644{
1645 BUG_ON(!irqs_disabled());
1646 if (rq1 == rq2) {
1647 raw_spin_lock(&rq1->lock);
1648 __acquire(rq2->lock); /* Fake it out ;) */
1649 } else {
1650 if (rq1 < rq2) {
1651 raw_spin_lock(&rq1->lock);
1652 raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
1653 } else {
1654 raw_spin_lock(&rq2->lock);
1655 raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
1656 }
1657 }
1658}
1659
1660/*
1661 * double_rq_unlock - safely unlock two runqueues
1662 *
1663 * Note this does not restore interrupts like task_rq_unlock,
1664 * you need to do so manually after calling.
1665 */
1666static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
1667 __releases(rq1->lock)
1668 __releases(rq2->lock)
1669{
1670 raw_spin_unlock(&rq1->lock);
1671 if (rq1 != rq2)
1672 raw_spin_unlock(&rq2->lock);
1673 else
1674 __release(rq2->lock);
1675}
1676
1677#else /* CONFIG_SMP */
1678
1679/*
1680 * double_rq_lock - safely lock two runqueues
1681 *
1682 * Note this does not disable interrupts like task_rq_lock,
1683 * you need to do so manually before calling.
1684 */
1685static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
1686 __acquires(rq1->lock)
1687 __acquires(rq2->lock)
1688{
1689 BUG_ON(!irqs_disabled());
1690 BUG_ON(rq1 != rq2);
1691 raw_spin_lock(&rq1->lock);
1692 __acquire(rq2->lock); /* Fake it out ;) */
1693}
1694
1695/*
1696 * double_rq_unlock - safely unlock two runqueues
1697 *
1698 * Note this does not restore interrupts like task_rq_unlock,
1699 * you need to do so manually after calling.
1700 */
1701static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
1702 __releases(rq1->lock)
1703 __releases(rq2->lock)
1704{
1705 BUG_ON(rq1 != rq2);
1706 raw_spin_unlock(&rq1->lock);
1707 __release(rq2->lock);
1708}
1709
1710#endif
1711
1712extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
1713extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
1714
1715#ifdef CONFIG_SCHED_DEBUG
1716extern void print_cfs_stats(struct seq_file *m, int cpu);
1717extern void print_rt_stats(struct seq_file *m, int cpu);
1718extern void print_dl_stats(struct seq_file *m, int cpu);
1719extern void
1720print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
1721
1722#ifdef CONFIG_NUMA_BALANCING
1723extern void
1724show_numa_stats(struct task_struct *p, struct seq_file *m);
1725extern void
1726print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
1727 unsigned long tpf, unsigned long gsf, unsigned long gpf);
1728#endif /* CONFIG_NUMA_BALANCING */
1729#endif /* CONFIG_SCHED_DEBUG */
1730
1731extern void init_cfs_rq(struct cfs_rq *cfs_rq);
1732extern void init_rt_rq(struct rt_rq *rt_rq);
1733extern void init_dl_rq(struct dl_rq *dl_rq);
1734
1735extern void cfs_bandwidth_usage_inc(void);
1736extern void cfs_bandwidth_usage_dec(void);
1737
1738#ifdef CONFIG_NO_HZ_COMMON
1739enum rq_nohz_flag_bits {
1740 NOHZ_TICK_STOPPED,
1741 NOHZ_BALANCE_KICK,
1742};
1743
1744#define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
1745
1746extern void nohz_balance_exit_idle(unsigned int cpu);
1747#else
1748static inline void nohz_balance_exit_idle(unsigned int cpu) { }
1749#endif
1750
1751#ifdef CONFIG_IRQ_TIME_ACCOUNTING
1752struct irqtime {
1753 u64 hardirq_time;
1754 u64 softirq_time;
1755 u64 irq_start_time;
1756 struct u64_stats_sync sync;
1757};
1758
1759DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
1760
1761static inline u64 irq_time_read(int cpu)
1762{
1763 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
1764 unsigned int seq;
1765 u64 total;
1766
1767 do {
1768 seq = __u64_stats_fetch_begin(&irqtime->sync);
1769 total = irqtime->softirq_time + irqtime->hardirq_time;
1770 } while (__u64_stats_fetch_retry(&irqtime->sync, seq));
1771
1772 return total;
1773}
1774#endif /* CONFIG_IRQ_TIME_ACCOUNTING */
1775
1776#ifdef CONFIG_CPU_FREQ
1777DECLARE_PER_CPU(struct update_util_data *, cpufreq_update_util_data);
1778
1779/**
1780 * cpufreq_update_util - Take a note about CPU utilization changes.
1781 * @rq: Runqueue to carry out the update for.
1782 * @flags: Update reason flags.
1783 *
1784 * This function is called by the scheduler on the CPU whose utilization is
1785 * being updated.
1786 *
1787 * It can only be called from RCU-sched read-side critical sections.
1788 *
1789 * The way cpufreq is currently arranged requires it to evaluate the CPU
1790 * performance state (frequency/voltage) on a regular basis to prevent it from
1791 * being stuck in a completely inadequate performance level for too long.
1792 * That is not guaranteed to happen if the updates are only triggered from CFS,
1793 * though, because they may not be coming in if RT or deadline tasks are active
1794 * all the time (or there are RT and DL tasks only).
1795 *
1796 * As a workaround for that issue, this function is called by the RT and DL
1797 * sched classes to trigger extra cpufreq updates to prevent it from stalling,
1798 * but that really is a band-aid. Going forward it should be replaced with
1799 * solutions targeted more specifically at RT and DL tasks.
1800 */
1801static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
1802{
1803 struct update_util_data *data;
1804
1805 data = rcu_dereference_sched(*this_cpu_ptr(&cpufreq_update_util_data));
1806 if (data)
1807 data->func(data, rq_clock(rq), flags);
1808}
1809
1810static inline void cpufreq_update_this_cpu(struct rq *rq, unsigned int flags)
1811{
1812 if (cpu_of(rq) == smp_processor_id())
1813 cpufreq_update_util(rq, flags);
1814}
1815#else
1816static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
1817static inline void cpufreq_update_this_cpu(struct rq *rq, unsigned int flags) {}
1818#endif /* CONFIG_CPU_FREQ */
1819
1820#ifdef arch_scale_freq_capacity
1821#ifndef arch_scale_freq_invariant
1822#define arch_scale_freq_invariant() (true)
1823#endif
1824#else /* arch_scale_freq_capacity */
1825#define arch_scale_freq_invariant() (false)
1826#endif