xref: /openbmc/linux/kernel/sched/sched.h (revision ca481398)
1 
2 #include <linux/sched.h>
3 #include <linux/sched/autogroup.h>
4 #include <linux/sched/sysctl.h>
5 #include <linux/sched/topology.h>
6 #include <linux/sched/rt.h>
7 #include <linux/sched/deadline.h>
8 #include <linux/sched/clock.h>
9 #include <linux/sched/wake_q.h>
10 #include <linux/sched/signal.h>
11 #include <linux/sched/numa_balancing.h>
12 #include <linux/sched/mm.h>
13 #include <linux/sched/cpufreq.h>
14 #include <linux/sched/stat.h>
15 #include <linux/sched/nohz.h>
16 #include <linux/sched/debug.h>
17 #include <linux/sched/hotplug.h>
18 #include <linux/sched/task.h>
19 #include <linux/sched/task_stack.h>
20 #include <linux/sched/cputime.h>
21 #include <linux/sched/init.h>
22 
23 #include <linux/u64_stats_sync.h>
24 #include <linux/kernel_stat.h>
25 #include <linux/binfmts.h>
26 #include <linux/mutex.h>
27 #include <linux/spinlock.h>
28 #include <linux/stop_machine.h>
29 #include <linux/irq_work.h>
30 #include <linux/tick.h>
31 #include <linux/slab.h>
32 
33 #ifdef CONFIG_PARAVIRT
34 #include <asm/paravirt.h>
35 #endif
36 
37 #include "cpupri.h"
38 #include "cpudeadline.h"
39 #include "cpuacct.h"
40 
41 #ifdef CONFIG_SCHED_DEBUG
42 # define SCHED_WARN_ON(x)	WARN_ONCE(x, #x)
43 #else
44 # define SCHED_WARN_ON(x)	({ (void)(x), 0; })
45 #endif
46 
47 struct rq;
48 struct cpuidle_state;
49 
50 /* task_struct::on_rq states: */
51 #define TASK_ON_RQ_QUEUED	1
52 #define TASK_ON_RQ_MIGRATING	2
53 
54 extern __read_mostly int scheduler_running;
55 
56 extern unsigned long calc_load_update;
57 extern atomic_long_t calc_load_tasks;
58 
59 extern void calc_global_load_tick(struct rq *this_rq);
60 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
61 
62 #ifdef CONFIG_SMP
63 extern void cpu_load_update_active(struct rq *this_rq);
64 #else
65 static inline void cpu_load_update_active(struct rq *this_rq) { }
66 #endif
67 
68 /*
69  * Helpers for converting nanosecond timing to jiffy resolution
70  */
71 #define NS_TO_JIFFIES(TIME)	((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
72 
73 /*
74  * Increase resolution of nice-level calculations for 64-bit architectures.
75  * The extra resolution improves shares distribution and load balancing of
76  * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
77  * hierarchies, especially on larger systems. This is not a user-visible change
78  * and does not change the user-interface for setting shares/weights.
79  *
80  * We increase resolution only if we have enough bits to allow this increased
81  * resolution (i.e. 64bit). The costs for increasing resolution when 32bit are
82  * pretty high and the returns do not justify the increased costs.
83  *
84  * Really only required when CONFIG_FAIR_GROUP_SCHED is also set, but to
85  * increase coverage and consistency always enable it on 64bit platforms.
86  */
87 #ifdef CONFIG_64BIT
88 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
89 # define scale_load(w)		((w) << SCHED_FIXEDPOINT_SHIFT)
90 # define scale_load_down(w)	((w) >> SCHED_FIXEDPOINT_SHIFT)
91 #else
92 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT)
93 # define scale_load(w)		(w)
94 # define scale_load_down(w)	(w)
95 #endif
96 
97 /*
98  * Task weight (visible to users) and its load (invisible to users) have
99  * independent resolution, but they should be well calibrated. We use
100  * scale_load() and scale_load_down(w) to convert between them. The
101  * following must be true:
102  *
103  *  scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD
104  *
105  */
106 #define NICE_0_LOAD		(1L << NICE_0_LOAD_SHIFT)
107 
108 /*
109  * Single value that decides SCHED_DEADLINE internal math precision.
110  * 10 -> just above 1us
111  * 9  -> just above 0.5us
112  */
113 #define DL_SCALE (10)
114 
115 /*
116  * These are the 'tuning knobs' of the scheduler:
117  */
118 
119 /*
120  * single value that denotes runtime == period, ie unlimited time.
121  */
122 #define RUNTIME_INF	((u64)~0ULL)
123 
124 static inline int idle_policy(int policy)
125 {
126 	return policy == SCHED_IDLE;
127 }
128 static inline int fair_policy(int policy)
129 {
130 	return policy == SCHED_NORMAL || policy == SCHED_BATCH;
131 }
132 
133 static inline int rt_policy(int policy)
134 {
135 	return policy == SCHED_FIFO || policy == SCHED_RR;
136 }
137 
138 static inline int dl_policy(int policy)
139 {
140 	return policy == SCHED_DEADLINE;
141 }
142 static inline bool valid_policy(int policy)
143 {
144 	return idle_policy(policy) || fair_policy(policy) ||
145 		rt_policy(policy) || dl_policy(policy);
146 }
147 
148 static inline int task_has_rt_policy(struct task_struct *p)
149 {
150 	return rt_policy(p->policy);
151 }
152 
153 static inline int task_has_dl_policy(struct task_struct *p)
154 {
155 	return dl_policy(p->policy);
156 }
157 
158 /*
159  * Tells if entity @a should preempt entity @b.
160  */
161 static inline bool
162 dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
163 {
164 	return dl_time_before(a->deadline, b->deadline);
165 }
166 
167 /*
168  * This is the priority-queue data structure of the RT scheduling class:
169  */
170 struct rt_prio_array {
171 	DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
172 	struct list_head queue[MAX_RT_PRIO];
173 };
174 
175 struct rt_bandwidth {
176 	/* nests inside the rq lock: */
177 	raw_spinlock_t		rt_runtime_lock;
178 	ktime_t			rt_period;
179 	u64			rt_runtime;
180 	struct hrtimer		rt_period_timer;
181 	unsigned int		rt_period_active;
182 };
183 
184 void __dl_clear_params(struct task_struct *p);
185 
186 /*
187  * To keep the bandwidth of -deadline tasks and groups under control
188  * we need some place where:
189  *  - store the maximum -deadline bandwidth of the system (the group);
190  *  - cache the fraction of that bandwidth that is currently allocated.
191  *
192  * This is all done in the data structure below. It is similar to the
193  * one used for RT-throttling (rt_bandwidth), with the main difference
194  * that, since here we are only interested in admission control, we
195  * do not decrease any runtime while the group "executes", neither we
196  * need a timer to replenish it.
197  *
198  * With respect to SMP, the bandwidth is given on a per-CPU basis,
199  * meaning that:
200  *  - dl_bw (< 100%) is the bandwidth of the system (group) on each CPU;
201  *  - dl_total_bw array contains, in the i-eth element, the currently
202  *    allocated bandwidth on the i-eth CPU.
203  * Moreover, groups consume bandwidth on each CPU, while tasks only
204  * consume bandwidth on the CPU they're running on.
205  * Finally, dl_total_bw_cpu is used to cache the index of dl_total_bw
206  * that will be shown the next time the proc or cgroup controls will
207  * be red. It on its turn can be changed by writing on its own
208  * control.
209  */
210 struct dl_bandwidth {
211 	raw_spinlock_t dl_runtime_lock;
212 	u64 dl_runtime;
213 	u64 dl_period;
214 };
215 
216 static inline int dl_bandwidth_enabled(void)
217 {
218 	return sysctl_sched_rt_runtime >= 0;
219 }
220 
221 struct dl_bw {
222 	raw_spinlock_t lock;
223 	u64 bw, total_bw;
224 };
225 
226 static inline void __dl_update(struct dl_bw *dl_b, s64 bw);
227 
228 static inline
229 void __dl_clear(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
230 {
231 	dl_b->total_bw -= tsk_bw;
232 	__dl_update(dl_b, (s32)tsk_bw / cpus);
233 }
234 
235 static inline
236 void __dl_add(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
237 {
238 	dl_b->total_bw += tsk_bw;
239 	__dl_update(dl_b, -((s32)tsk_bw / cpus));
240 }
241 
242 static inline
243 bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw)
244 {
245 	return dl_b->bw != -1 &&
246 	       dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw;
247 }
248 
249 void dl_change_utilization(struct task_struct *p, u64 new_bw);
250 extern void init_dl_bw(struct dl_bw *dl_b);
251 extern int sched_dl_global_validate(void);
252 extern void sched_dl_do_global(void);
253 extern int sched_dl_overflow(struct task_struct *p, int policy,
254 			     const struct sched_attr *attr);
255 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
256 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
257 extern bool __checkparam_dl(const struct sched_attr *attr);
258 extern void __dl_clear_params(struct task_struct *p);
259 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
260 extern int dl_task_can_attach(struct task_struct *p,
261 			      const struct cpumask *cs_cpus_allowed);
262 extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur,
263 					const struct cpumask *trial);
264 extern bool dl_cpu_busy(unsigned int cpu);
265 
266 #ifdef CONFIG_CGROUP_SCHED
267 
268 #include <linux/cgroup.h>
269 
270 struct cfs_rq;
271 struct rt_rq;
272 
273 extern struct list_head task_groups;
274 
275 struct cfs_bandwidth {
276 #ifdef CONFIG_CFS_BANDWIDTH
277 	raw_spinlock_t lock;
278 	ktime_t period;
279 	u64 quota, runtime;
280 	s64 hierarchical_quota;
281 	u64 runtime_expires;
282 
283 	int idle, period_active;
284 	struct hrtimer period_timer, slack_timer;
285 	struct list_head throttled_cfs_rq;
286 
287 	/* statistics */
288 	int nr_periods, nr_throttled;
289 	u64 throttled_time;
290 #endif
291 };
292 
293 /* task group related information */
294 struct task_group {
295 	struct cgroup_subsys_state css;
296 
297 #ifdef CONFIG_FAIR_GROUP_SCHED
298 	/* schedulable entities of this group on each cpu */
299 	struct sched_entity **se;
300 	/* runqueue "owned" by this group on each cpu */
301 	struct cfs_rq **cfs_rq;
302 	unsigned long shares;
303 
304 #ifdef	CONFIG_SMP
305 	/*
306 	 * load_avg can be heavily contended at clock tick time, so put
307 	 * it in its own cacheline separated from the fields above which
308 	 * will also be accessed at each tick.
309 	 */
310 	atomic_long_t load_avg ____cacheline_aligned;
311 #endif
312 #endif
313 
314 #ifdef CONFIG_RT_GROUP_SCHED
315 	struct sched_rt_entity **rt_se;
316 	struct rt_rq **rt_rq;
317 
318 	struct rt_bandwidth rt_bandwidth;
319 #endif
320 
321 	struct rcu_head rcu;
322 	struct list_head list;
323 
324 	struct task_group *parent;
325 	struct list_head siblings;
326 	struct list_head children;
327 
328 #ifdef CONFIG_SCHED_AUTOGROUP
329 	struct autogroup *autogroup;
330 #endif
331 
332 	struct cfs_bandwidth cfs_bandwidth;
333 };
334 
335 #ifdef CONFIG_FAIR_GROUP_SCHED
336 #define ROOT_TASK_GROUP_LOAD	NICE_0_LOAD
337 
338 /*
339  * A weight of 0 or 1 can cause arithmetics problems.
340  * A weight of a cfs_rq is the sum of weights of which entities
341  * are queued on this cfs_rq, so a weight of a entity should not be
342  * too large, so as the shares value of a task group.
343  * (The default weight is 1024 - so there's no practical
344  *  limitation from this.)
345  */
346 #define MIN_SHARES	(1UL <<  1)
347 #define MAX_SHARES	(1UL << 18)
348 #endif
349 
350 typedef int (*tg_visitor)(struct task_group *, void *);
351 
352 extern int walk_tg_tree_from(struct task_group *from,
353 			     tg_visitor down, tg_visitor up, void *data);
354 
355 /*
356  * Iterate the full tree, calling @down when first entering a node and @up when
357  * leaving it for the final time.
358  *
359  * Caller must hold rcu_lock or sufficient equivalent.
360  */
361 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
362 {
363 	return walk_tg_tree_from(&root_task_group, down, up, data);
364 }
365 
366 extern int tg_nop(struct task_group *tg, void *data);
367 
368 extern void free_fair_sched_group(struct task_group *tg);
369 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
370 extern void online_fair_sched_group(struct task_group *tg);
371 extern void unregister_fair_sched_group(struct task_group *tg);
372 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
373 			struct sched_entity *se, int cpu,
374 			struct sched_entity *parent);
375 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
376 
377 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
378 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
379 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
380 
381 extern void free_rt_sched_group(struct task_group *tg);
382 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
383 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
384 		struct sched_rt_entity *rt_se, int cpu,
385 		struct sched_rt_entity *parent);
386 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
387 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
388 extern long sched_group_rt_runtime(struct task_group *tg);
389 extern long sched_group_rt_period(struct task_group *tg);
390 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
391 
392 extern struct task_group *sched_create_group(struct task_group *parent);
393 extern void sched_online_group(struct task_group *tg,
394 			       struct task_group *parent);
395 extern void sched_destroy_group(struct task_group *tg);
396 extern void sched_offline_group(struct task_group *tg);
397 
398 extern void sched_move_task(struct task_struct *tsk);
399 
400 #ifdef CONFIG_FAIR_GROUP_SCHED
401 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
402 
403 #ifdef CONFIG_SMP
404 extern void set_task_rq_fair(struct sched_entity *se,
405 			     struct cfs_rq *prev, struct cfs_rq *next);
406 #else /* !CONFIG_SMP */
407 static inline void set_task_rq_fair(struct sched_entity *se,
408 			     struct cfs_rq *prev, struct cfs_rq *next) { }
409 #endif /* CONFIG_SMP */
410 #endif /* CONFIG_FAIR_GROUP_SCHED */
411 
412 #else /* CONFIG_CGROUP_SCHED */
413 
414 struct cfs_bandwidth { };
415 
416 #endif	/* CONFIG_CGROUP_SCHED */
417 
418 /* CFS-related fields in a runqueue */
419 struct cfs_rq {
420 	struct load_weight load;
421 	unsigned int nr_running, h_nr_running;
422 
423 	u64 exec_clock;
424 	u64 min_vruntime;
425 #ifndef CONFIG_64BIT
426 	u64 min_vruntime_copy;
427 #endif
428 
429 	struct rb_root_cached tasks_timeline;
430 
431 	/*
432 	 * 'curr' points to currently running entity on this cfs_rq.
433 	 * It is set to NULL otherwise (i.e when none are currently running).
434 	 */
435 	struct sched_entity *curr, *next, *last, *skip;
436 
437 #ifdef	CONFIG_SCHED_DEBUG
438 	unsigned int nr_spread_over;
439 #endif
440 
441 #ifdef CONFIG_SMP
442 	/*
443 	 * CFS load tracking
444 	 */
445 	struct sched_avg avg;
446 	u64 runnable_load_sum;
447 	unsigned long runnable_load_avg;
448 #ifdef CONFIG_FAIR_GROUP_SCHED
449 	unsigned long tg_load_avg_contrib;
450 	unsigned long propagate_avg;
451 #endif
452 	atomic_long_t removed_load_avg, removed_util_avg;
453 #ifndef CONFIG_64BIT
454 	u64 load_last_update_time_copy;
455 #endif
456 
457 #ifdef CONFIG_FAIR_GROUP_SCHED
458 	/*
459 	 *   h_load = weight * f(tg)
460 	 *
461 	 * Where f(tg) is the recursive weight fraction assigned to
462 	 * this group.
463 	 */
464 	unsigned long h_load;
465 	u64 last_h_load_update;
466 	struct sched_entity *h_load_next;
467 #endif /* CONFIG_FAIR_GROUP_SCHED */
468 #endif /* CONFIG_SMP */
469 
470 #ifdef CONFIG_FAIR_GROUP_SCHED
471 	struct rq *rq;	/* cpu runqueue to which this cfs_rq is attached */
472 
473 	/*
474 	 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
475 	 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
476 	 * (like users, containers etc.)
477 	 *
478 	 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This
479 	 * list is used during load balance.
480 	 */
481 	int on_list;
482 	struct list_head leaf_cfs_rq_list;
483 	struct task_group *tg;	/* group that "owns" this runqueue */
484 
485 #ifdef CONFIG_CFS_BANDWIDTH
486 	int runtime_enabled;
487 	u64 runtime_expires;
488 	s64 runtime_remaining;
489 
490 	u64 throttled_clock, throttled_clock_task;
491 	u64 throttled_clock_task_time;
492 	int throttled, throttle_count;
493 	struct list_head throttled_list;
494 #endif /* CONFIG_CFS_BANDWIDTH */
495 #endif /* CONFIG_FAIR_GROUP_SCHED */
496 };
497 
498 static inline int rt_bandwidth_enabled(void)
499 {
500 	return sysctl_sched_rt_runtime >= 0;
501 }
502 
503 /* RT IPI pull logic requires IRQ_WORK */
504 #ifdef CONFIG_IRQ_WORK
505 # define HAVE_RT_PUSH_IPI
506 #endif
507 
508 /* Real-Time classes' related field in a runqueue: */
509 struct rt_rq {
510 	struct rt_prio_array active;
511 	unsigned int rt_nr_running;
512 	unsigned int rr_nr_running;
513 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
514 	struct {
515 		int curr; /* highest queued rt task prio */
516 #ifdef CONFIG_SMP
517 		int next; /* next highest */
518 #endif
519 	} highest_prio;
520 #endif
521 #ifdef CONFIG_SMP
522 	unsigned long rt_nr_migratory;
523 	unsigned long rt_nr_total;
524 	int overloaded;
525 	struct plist_head pushable_tasks;
526 #ifdef HAVE_RT_PUSH_IPI
527 	int push_flags;
528 	int push_cpu;
529 	struct irq_work push_work;
530 	raw_spinlock_t push_lock;
531 #endif
532 #endif /* CONFIG_SMP */
533 	int rt_queued;
534 
535 	int rt_throttled;
536 	u64 rt_time;
537 	u64 rt_runtime;
538 	/* Nests inside the rq lock: */
539 	raw_spinlock_t rt_runtime_lock;
540 
541 #ifdef CONFIG_RT_GROUP_SCHED
542 	unsigned long rt_nr_boosted;
543 
544 	struct rq *rq;
545 	struct task_group *tg;
546 #endif
547 };
548 
549 /* Deadline class' related fields in a runqueue */
550 struct dl_rq {
551 	/* runqueue is an rbtree, ordered by deadline */
552 	struct rb_root_cached root;
553 
554 	unsigned long dl_nr_running;
555 
556 #ifdef CONFIG_SMP
557 	/*
558 	 * Deadline values of the currently executing and the
559 	 * earliest ready task on this rq. Caching these facilitates
560 	 * the decision wether or not a ready but not running task
561 	 * should migrate somewhere else.
562 	 */
563 	struct {
564 		u64 curr;
565 		u64 next;
566 	} earliest_dl;
567 
568 	unsigned long dl_nr_migratory;
569 	int overloaded;
570 
571 	/*
572 	 * Tasks on this rq that can be pushed away. They are kept in
573 	 * an rb-tree, ordered by tasks' deadlines, with caching
574 	 * of the leftmost (earliest deadline) element.
575 	 */
576 	struct rb_root_cached pushable_dl_tasks_root;
577 #else
578 	struct dl_bw dl_bw;
579 #endif
580 	/*
581 	 * "Active utilization" for this runqueue: increased when a
582 	 * task wakes up (becomes TASK_RUNNING) and decreased when a
583 	 * task blocks
584 	 */
585 	u64 running_bw;
586 
587 	/*
588 	 * Utilization of the tasks "assigned" to this runqueue (including
589 	 * the tasks that are in runqueue and the tasks that executed on this
590 	 * CPU and blocked). Increased when a task moves to this runqueue, and
591 	 * decreased when the task moves away (migrates, changes scheduling
592 	 * policy, or terminates).
593 	 * This is needed to compute the "inactive utilization" for the
594 	 * runqueue (inactive utilization = this_bw - running_bw).
595 	 */
596 	u64 this_bw;
597 	u64 extra_bw;
598 
599 	/*
600 	 * Inverse of the fraction of CPU utilization that can be reclaimed
601 	 * by the GRUB algorithm.
602 	 */
603 	u64 bw_ratio;
604 };
605 
606 #ifdef CONFIG_SMP
607 
608 static inline bool sched_asym_prefer(int a, int b)
609 {
610 	return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
611 }
612 
613 /*
614  * We add the notion of a root-domain which will be used to define per-domain
615  * variables. Each exclusive cpuset essentially defines an island domain by
616  * fully partitioning the member cpus from any other cpuset. Whenever a new
617  * exclusive cpuset is created, we also create and attach a new root-domain
618  * object.
619  *
620  */
621 struct root_domain {
622 	atomic_t refcount;
623 	atomic_t rto_count;
624 	struct rcu_head rcu;
625 	cpumask_var_t span;
626 	cpumask_var_t online;
627 
628 	/* Indicate more than one runnable task for any CPU */
629 	bool overload;
630 
631 	/*
632 	 * The bit corresponding to a CPU gets set here if such CPU has more
633 	 * than one runnable -deadline task (as it is below for RT tasks).
634 	 */
635 	cpumask_var_t dlo_mask;
636 	atomic_t dlo_count;
637 	struct dl_bw dl_bw;
638 	struct cpudl cpudl;
639 
640 	/*
641 	 * The "RT overload" flag: it gets set if a CPU has more than
642 	 * one runnable RT task.
643 	 */
644 	cpumask_var_t rto_mask;
645 	struct cpupri cpupri;
646 
647 	unsigned long max_cpu_capacity;
648 };
649 
650 extern struct root_domain def_root_domain;
651 extern struct mutex sched_domains_mutex;
652 
653 extern void init_defrootdomain(void);
654 extern int sched_init_domains(const struct cpumask *cpu_map);
655 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
656 
657 #endif /* CONFIG_SMP */
658 
659 /*
660  * This is the main, per-CPU runqueue data structure.
661  *
662  * Locking rule: those places that want to lock multiple runqueues
663  * (such as the load balancing or the thread migration code), lock
664  * acquire operations must be ordered by ascending &runqueue.
665  */
666 struct rq {
667 	/* runqueue lock: */
668 	raw_spinlock_t lock;
669 
670 	/*
671 	 * nr_running and cpu_load should be in the same cacheline because
672 	 * remote CPUs use both these fields when doing load calculation.
673 	 */
674 	unsigned int nr_running;
675 #ifdef CONFIG_NUMA_BALANCING
676 	unsigned int nr_numa_running;
677 	unsigned int nr_preferred_running;
678 #endif
679 	#define CPU_LOAD_IDX_MAX 5
680 	unsigned long cpu_load[CPU_LOAD_IDX_MAX];
681 #ifdef CONFIG_NO_HZ_COMMON
682 #ifdef CONFIG_SMP
683 	unsigned long last_load_update_tick;
684 #endif /* CONFIG_SMP */
685 	unsigned long nohz_flags;
686 #endif /* CONFIG_NO_HZ_COMMON */
687 #ifdef CONFIG_NO_HZ_FULL
688 	unsigned long last_sched_tick;
689 #endif
690 	/* capture load from *all* tasks on this cpu: */
691 	struct load_weight load;
692 	unsigned long nr_load_updates;
693 	u64 nr_switches;
694 
695 	struct cfs_rq cfs;
696 	struct rt_rq rt;
697 	struct dl_rq dl;
698 
699 #ifdef CONFIG_FAIR_GROUP_SCHED
700 	/* list of leaf cfs_rq on this cpu: */
701 	struct list_head leaf_cfs_rq_list;
702 	struct list_head *tmp_alone_branch;
703 #endif /* CONFIG_FAIR_GROUP_SCHED */
704 
705 	/*
706 	 * This is part of a global counter where only the total sum
707 	 * over all CPUs matters. A task can increase this counter on
708 	 * one CPU and if it got migrated afterwards it may decrease
709 	 * it on another CPU. Always updated under the runqueue lock:
710 	 */
711 	unsigned long nr_uninterruptible;
712 
713 	struct task_struct *curr, *idle, *stop;
714 	unsigned long next_balance;
715 	struct mm_struct *prev_mm;
716 
717 	unsigned int clock_update_flags;
718 	u64 clock;
719 	u64 clock_task;
720 
721 	atomic_t nr_iowait;
722 
723 #ifdef CONFIG_SMP
724 	struct root_domain *rd;
725 	struct sched_domain *sd;
726 
727 	unsigned long cpu_capacity;
728 	unsigned long cpu_capacity_orig;
729 
730 	struct callback_head *balance_callback;
731 
732 	unsigned char idle_balance;
733 	/* For active balancing */
734 	int active_balance;
735 	int push_cpu;
736 	struct cpu_stop_work active_balance_work;
737 	/* cpu of this runqueue: */
738 	int cpu;
739 	int online;
740 
741 	struct list_head cfs_tasks;
742 
743 	u64 rt_avg;
744 	u64 age_stamp;
745 	u64 idle_stamp;
746 	u64 avg_idle;
747 
748 	/* This is used to determine avg_idle's max value */
749 	u64 max_idle_balance_cost;
750 #endif
751 
752 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
753 	u64 prev_irq_time;
754 #endif
755 #ifdef CONFIG_PARAVIRT
756 	u64 prev_steal_time;
757 #endif
758 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
759 	u64 prev_steal_time_rq;
760 #endif
761 
762 	/* calc_load related fields */
763 	unsigned long calc_load_update;
764 	long calc_load_active;
765 
766 #ifdef CONFIG_SCHED_HRTICK
767 #ifdef CONFIG_SMP
768 	int hrtick_csd_pending;
769 	call_single_data_t hrtick_csd;
770 #endif
771 	struct hrtimer hrtick_timer;
772 #endif
773 
774 #ifdef CONFIG_SCHEDSTATS
775 	/* latency stats */
776 	struct sched_info rq_sched_info;
777 	unsigned long long rq_cpu_time;
778 	/* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
779 
780 	/* sys_sched_yield() stats */
781 	unsigned int yld_count;
782 
783 	/* schedule() stats */
784 	unsigned int sched_count;
785 	unsigned int sched_goidle;
786 
787 	/* try_to_wake_up() stats */
788 	unsigned int ttwu_count;
789 	unsigned int ttwu_local;
790 #endif
791 
792 #ifdef CONFIG_SMP
793 	struct llist_head wake_list;
794 #endif
795 
796 #ifdef CONFIG_CPU_IDLE
797 	/* Must be inspected within a rcu lock section */
798 	struct cpuidle_state *idle_state;
799 #endif
800 };
801 
802 static inline int cpu_of(struct rq *rq)
803 {
804 #ifdef CONFIG_SMP
805 	return rq->cpu;
806 #else
807 	return 0;
808 #endif
809 }
810 
811 
812 #ifdef CONFIG_SCHED_SMT
813 
814 extern struct static_key_false sched_smt_present;
815 
816 extern void __update_idle_core(struct rq *rq);
817 
818 static inline void update_idle_core(struct rq *rq)
819 {
820 	if (static_branch_unlikely(&sched_smt_present))
821 		__update_idle_core(rq);
822 }
823 
824 #else
825 static inline void update_idle_core(struct rq *rq) { }
826 #endif
827 
828 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
829 
830 #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
831 #define this_rq()		this_cpu_ptr(&runqueues)
832 #define task_rq(p)		cpu_rq(task_cpu(p))
833 #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
834 #define raw_rq()		raw_cpu_ptr(&runqueues)
835 
836 static inline u64 __rq_clock_broken(struct rq *rq)
837 {
838 	return READ_ONCE(rq->clock);
839 }
840 
841 /*
842  * rq::clock_update_flags bits
843  *
844  * %RQCF_REQ_SKIP - will request skipping of clock update on the next
845  *  call to __schedule(). This is an optimisation to avoid
846  *  neighbouring rq clock updates.
847  *
848  * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
849  *  in effect and calls to update_rq_clock() are being ignored.
850  *
851  * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
852  *  made to update_rq_clock() since the last time rq::lock was pinned.
853  *
854  * If inside of __schedule(), clock_update_flags will have been
855  * shifted left (a left shift is a cheap operation for the fast path
856  * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
857  *
858  *	if (rq-clock_update_flags >= RQCF_UPDATED)
859  *
860  * to check if %RQCF_UPADTED is set. It'll never be shifted more than
861  * one position though, because the next rq_unpin_lock() will shift it
862  * back.
863  */
864 #define RQCF_REQ_SKIP	0x01
865 #define RQCF_ACT_SKIP	0x02
866 #define RQCF_UPDATED	0x04
867 
868 static inline void assert_clock_updated(struct rq *rq)
869 {
870 	/*
871 	 * The only reason for not seeing a clock update since the
872 	 * last rq_pin_lock() is if we're currently skipping updates.
873 	 */
874 	SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
875 }
876 
877 static inline u64 rq_clock(struct rq *rq)
878 {
879 	lockdep_assert_held(&rq->lock);
880 	assert_clock_updated(rq);
881 
882 	return rq->clock;
883 }
884 
885 static inline u64 rq_clock_task(struct rq *rq)
886 {
887 	lockdep_assert_held(&rq->lock);
888 	assert_clock_updated(rq);
889 
890 	return rq->clock_task;
891 }
892 
893 static inline void rq_clock_skip_update(struct rq *rq, bool skip)
894 {
895 	lockdep_assert_held(&rq->lock);
896 	if (skip)
897 		rq->clock_update_flags |= RQCF_REQ_SKIP;
898 	else
899 		rq->clock_update_flags &= ~RQCF_REQ_SKIP;
900 }
901 
902 struct rq_flags {
903 	unsigned long flags;
904 	struct pin_cookie cookie;
905 #ifdef CONFIG_SCHED_DEBUG
906 	/*
907 	 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
908 	 * current pin context is stashed here in case it needs to be
909 	 * restored in rq_repin_lock().
910 	 */
911 	unsigned int clock_update_flags;
912 #endif
913 };
914 
915 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
916 {
917 	rf->cookie = lockdep_pin_lock(&rq->lock);
918 
919 #ifdef CONFIG_SCHED_DEBUG
920 	rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
921 	rf->clock_update_flags = 0;
922 #endif
923 }
924 
925 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
926 {
927 #ifdef CONFIG_SCHED_DEBUG
928 	if (rq->clock_update_flags > RQCF_ACT_SKIP)
929 		rf->clock_update_flags = RQCF_UPDATED;
930 #endif
931 
932 	lockdep_unpin_lock(&rq->lock, rf->cookie);
933 }
934 
935 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
936 {
937 	lockdep_repin_lock(&rq->lock, rf->cookie);
938 
939 #ifdef CONFIG_SCHED_DEBUG
940 	/*
941 	 * Restore the value we stashed in @rf for this pin context.
942 	 */
943 	rq->clock_update_flags |= rf->clock_update_flags;
944 #endif
945 }
946 
947 #ifdef CONFIG_NUMA
948 enum numa_topology_type {
949 	NUMA_DIRECT,
950 	NUMA_GLUELESS_MESH,
951 	NUMA_BACKPLANE,
952 };
953 extern enum numa_topology_type sched_numa_topology_type;
954 extern int sched_max_numa_distance;
955 extern bool find_numa_distance(int distance);
956 #endif
957 
958 #ifdef CONFIG_NUMA
959 extern void sched_init_numa(void);
960 extern void sched_domains_numa_masks_set(unsigned int cpu);
961 extern void sched_domains_numa_masks_clear(unsigned int cpu);
962 #else
963 static inline void sched_init_numa(void) { }
964 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
965 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
966 #endif
967 
968 #ifdef CONFIG_NUMA_BALANCING
969 /* The regions in numa_faults array from task_struct */
970 enum numa_faults_stats {
971 	NUMA_MEM = 0,
972 	NUMA_CPU,
973 	NUMA_MEMBUF,
974 	NUMA_CPUBUF
975 };
976 extern void sched_setnuma(struct task_struct *p, int node);
977 extern int migrate_task_to(struct task_struct *p, int cpu);
978 extern int migrate_swap(struct task_struct *, struct task_struct *);
979 #endif /* CONFIG_NUMA_BALANCING */
980 
981 #ifdef CONFIG_SMP
982 
983 static inline void
984 queue_balance_callback(struct rq *rq,
985 		       struct callback_head *head,
986 		       void (*func)(struct rq *rq))
987 {
988 	lockdep_assert_held(&rq->lock);
989 
990 	if (unlikely(head->next))
991 		return;
992 
993 	head->func = (void (*)(struct callback_head *))func;
994 	head->next = rq->balance_callback;
995 	rq->balance_callback = head;
996 }
997 
998 extern void sched_ttwu_pending(void);
999 
1000 #define rcu_dereference_check_sched_domain(p) \
1001 	rcu_dereference_check((p), \
1002 			      lockdep_is_held(&sched_domains_mutex))
1003 
1004 /*
1005  * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1006  * See detach_destroy_domains: synchronize_sched for details.
1007  *
1008  * The domain tree of any CPU may only be accessed from within
1009  * preempt-disabled sections.
1010  */
1011 #define for_each_domain(cpu, __sd) \
1012 	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1013 			__sd; __sd = __sd->parent)
1014 
1015 #define for_each_lower_domain(sd) for (; sd; sd = sd->child)
1016 
1017 /**
1018  * highest_flag_domain - Return highest sched_domain containing flag.
1019  * @cpu:	The cpu whose highest level of sched domain is to
1020  *		be returned.
1021  * @flag:	The flag to check for the highest sched_domain
1022  *		for the given cpu.
1023  *
1024  * Returns the highest sched_domain of a cpu which contains the given flag.
1025  */
1026 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1027 {
1028 	struct sched_domain *sd, *hsd = NULL;
1029 
1030 	for_each_domain(cpu, sd) {
1031 		if (!(sd->flags & flag))
1032 			break;
1033 		hsd = sd;
1034 	}
1035 
1036 	return hsd;
1037 }
1038 
1039 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1040 {
1041 	struct sched_domain *sd;
1042 
1043 	for_each_domain(cpu, sd) {
1044 		if (sd->flags & flag)
1045 			break;
1046 	}
1047 
1048 	return sd;
1049 }
1050 
1051 DECLARE_PER_CPU(struct sched_domain *, sd_llc);
1052 DECLARE_PER_CPU(int, sd_llc_size);
1053 DECLARE_PER_CPU(int, sd_llc_id);
1054 DECLARE_PER_CPU(struct sched_domain_shared *, sd_llc_shared);
1055 DECLARE_PER_CPU(struct sched_domain *, sd_numa);
1056 DECLARE_PER_CPU(struct sched_domain *, sd_asym);
1057 
1058 struct sched_group_capacity {
1059 	atomic_t ref;
1060 	/*
1061 	 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
1062 	 * for a single CPU.
1063 	 */
1064 	unsigned long capacity;
1065 	unsigned long min_capacity; /* Min per-CPU capacity in group */
1066 	unsigned long next_update;
1067 	int imbalance; /* XXX unrelated to capacity but shared group state */
1068 
1069 #ifdef CONFIG_SCHED_DEBUG
1070 	int id;
1071 #endif
1072 
1073 	unsigned long cpumask[0]; /* balance mask */
1074 };
1075 
1076 struct sched_group {
1077 	struct sched_group *next;	/* Must be a circular list */
1078 	atomic_t ref;
1079 
1080 	unsigned int group_weight;
1081 	struct sched_group_capacity *sgc;
1082 	int asym_prefer_cpu;		/* cpu of highest priority in group */
1083 
1084 	/*
1085 	 * The CPUs this group covers.
1086 	 *
1087 	 * NOTE: this field is variable length. (Allocated dynamically
1088 	 * by attaching extra space to the end of the structure,
1089 	 * depending on how many CPUs the kernel has booted up with)
1090 	 */
1091 	unsigned long cpumask[0];
1092 };
1093 
1094 static inline struct cpumask *sched_group_span(struct sched_group *sg)
1095 {
1096 	return to_cpumask(sg->cpumask);
1097 }
1098 
1099 /*
1100  * See build_balance_mask().
1101  */
1102 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
1103 {
1104 	return to_cpumask(sg->sgc->cpumask);
1105 }
1106 
1107 /**
1108  * group_first_cpu - Returns the first cpu in the cpumask of a sched_group.
1109  * @group: The group whose first cpu is to be returned.
1110  */
1111 static inline unsigned int group_first_cpu(struct sched_group *group)
1112 {
1113 	return cpumask_first(sched_group_span(group));
1114 }
1115 
1116 extern int group_balance_cpu(struct sched_group *sg);
1117 
1118 #if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
1119 void register_sched_domain_sysctl(void);
1120 void dirty_sched_domain_sysctl(int cpu);
1121 void unregister_sched_domain_sysctl(void);
1122 #else
1123 static inline void register_sched_domain_sysctl(void)
1124 {
1125 }
1126 static inline void dirty_sched_domain_sysctl(int cpu)
1127 {
1128 }
1129 static inline void unregister_sched_domain_sysctl(void)
1130 {
1131 }
1132 #endif
1133 
1134 #else
1135 
1136 static inline void sched_ttwu_pending(void) { }
1137 
1138 #endif /* CONFIG_SMP */
1139 
1140 #include "stats.h"
1141 #include "autogroup.h"
1142 
1143 #ifdef CONFIG_CGROUP_SCHED
1144 
1145 /*
1146  * Return the group to which this tasks belongs.
1147  *
1148  * We cannot use task_css() and friends because the cgroup subsystem
1149  * changes that value before the cgroup_subsys::attach() method is called,
1150  * therefore we cannot pin it and might observe the wrong value.
1151  *
1152  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
1153  * core changes this before calling sched_move_task().
1154  *
1155  * Instead we use a 'copy' which is updated from sched_move_task() while
1156  * holding both task_struct::pi_lock and rq::lock.
1157  */
1158 static inline struct task_group *task_group(struct task_struct *p)
1159 {
1160 	return p->sched_task_group;
1161 }
1162 
1163 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
1164 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
1165 {
1166 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
1167 	struct task_group *tg = task_group(p);
1168 #endif
1169 
1170 #ifdef CONFIG_FAIR_GROUP_SCHED
1171 	set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
1172 	p->se.cfs_rq = tg->cfs_rq[cpu];
1173 	p->se.parent = tg->se[cpu];
1174 #endif
1175 
1176 #ifdef CONFIG_RT_GROUP_SCHED
1177 	p->rt.rt_rq  = tg->rt_rq[cpu];
1178 	p->rt.parent = tg->rt_se[cpu];
1179 #endif
1180 }
1181 
1182 #else /* CONFIG_CGROUP_SCHED */
1183 
1184 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
1185 static inline struct task_group *task_group(struct task_struct *p)
1186 {
1187 	return NULL;
1188 }
1189 
1190 #endif /* CONFIG_CGROUP_SCHED */
1191 
1192 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
1193 {
1194 	set_task_rq(p, cpu);
1195 #ifdef CONFIG_SMP
1196 	/*
1197 	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
1198 	 * successfuly executed on another CPU. We must ensure that updates of
1199 	 * per-task data have been completed by this moment.
1200 	 */
1201 	smp_wmb();
1202 #ifdef CONFIG_THREAD_INFO_IN_TASK
1203 	p->cpu = cpu;
1204 #else
1205 	task_thread_info(p)->cpu = cpu;
1206 #endif
1207 	p->wake_cpu = cpu;
1208 #endif
1209 }
1210 
1211 /*
1212  * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
1213  */
1214 #ifdef CONFIG_SCHED_DEBUG
1215 # include <linux/static_key.h>
1216 # define const_debug __read_mostly
1217 #else
1218 # define const_debug const
1219 #endif
1220 
1221 extern const_debug unsigned int sysctl_sched_features;
1222 
1223 #define SCHED_FEAT(name, enabled)	\
1224 	__SCHED_FEAT_##name ,
1225 
1226 enum {
1227 #include "features.h"
1228 	__SCHED_FEAT_NR,
1229 };
1230 
1231 #undef SCHED_FEAT
1232 
1233 #if defined(CONFIG_SCHED_DEBUG) && defined(HAVE_JUMP_LABEL)
1234 #define SCHED_FEAT(name, enabled)					\
1235 static __always_inline bool static_branch_##name(struct static_key *key) \
1236 {									\
1237 	return static_key_##enabled(key);				\
1238 }
1239 
1240 #include "features.h"
1241 
1242 #undef SCHED_FEAT
1243 
1244 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
1245 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
1246 #else /* !(SCHED_DEBUG && HAVE_JUMP_LABEL) */
1247 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1248 #endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */
1249 
1250 extern struct static_key_false sched_numa_balancing;
1251 extern struct static_key_false sched_schedstats;
1252 
1253 static inline u64 global_rt_period(void)
1254 {
1255 	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
1256 }
1257 
1258 static inline u64 global_rt_runtime(void)
1259 {
1260 	if (sysctl_sched_rt_runtime < 0)
1261 		return RUNTIME_INF;
1262 
1263 	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
1264 }
1265 
1266 static inline int task_current(struct rq *rq, struct task_struct *p)
1267 {
1268 	return rq->curr == p;
1269 }
1270 
1271 static inline int task_running(struct rq *rq, struct task_struct *p)
1272 {
1273 #ifdef CONFIG_SMP
1274 	return p->on_cpu;
1275 #else
1276 	return task_current(rq, p);
1277 #endif
1278 }
1279 
1280 static inline int task_on_rq_queued(struct task_struct *p)
1281 {
1282 	return p->on_rq == TASK_ON_RQ_QUEUED;
1283 }
1284 
1285 static inline int task_on_rq_migrating(struct task_struct *p)
1286 {
1287 	return p->on_rq == TASK_ON_RQ_MIGRATING;
1288 }
1289 
1290 #ifndef prepare_arch_switch
1291 # define prepare_arch_switch(next)	do { } while (0)
1292 #endif
1293 #ifndef finish_arch_post_lock_switch
1294 # define finish_arch_post_lock_switch()	do { } while (0)
1295 #endif
1296 
1297 static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
1298 {
1299 #ifdef CONFIG_SMP
1300 	/*
1301 	 * We can optimise this out completely for !SMP, because the
1302 	 * SMP rebalancing from interrupt is the only thing that cares
1303 	 * here.
1304 	 */
1305 	next->on_cpu = 1;
1306 #endif
1307 }
1308 
1309 static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
1310 {
1311 #ifdef CONFIG_SMP
1312 	/*
1313 	 * After ->on_cpu is cleared, the task can be moved to a different CPU.
1314 	 * We must ensure this doesn't happen until the switch is completely
1315 	 * finished.
1316 	 *
1317 	 * In particular, the load of prev->state in finish_task_switch() must
1318 	 * happen before this.
1319 	 *
1320 	 * Pairs with the smp_cond_load_acquire() in try_to_wake_up().
1321 	 */
1322 	smp_store_release(&prev->on_cpu, 0);
1323 #endif
1324 #ifdef CONFIG_DEBUG_SPINLOCK
1325 	/* this is a valid case when another task releases the spinlock */
1326 	rq->lock.owner = current;
1327 #endif
1328 	/*
1329 	 * If we are tracking spinlock dependencies then we have to
1330 	 * fix up the runqueue lock - which gets 'carried over' from
1331 	 * prev into current:
1332 	 */
1333 	spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_);
1334 
1335 	raw_spin_unlock_irq(&rq->lock);
1336 }
1337 
1338 /*
1339  * wake flags
1340  */
1341 #define WF_SYNC		0x01		/* waker goes to sleep after wakeup */
1342 #define WF_FORK		0x02		/* child wakeup after fork */
1343 #define WF_MIGRATED	0x4		/* internal use, task got migrated */
1344 
1345 /*
1346  * To aid in avoiding the subversion of "niceness" due to uneven distribution
1347  * of tasks with abnormal "nice" values across CPUs the contribution that
1348  * each task makes to its run queue's load is weighted according to its
1349  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
1350  * scaled version of the new time slice allocation that they receive on time
1351  * slice expiry etc.
1352  */
1353 
1354 #define WEIGHT_IDLEPRIO                3
1355 #define WMULT_IDLEPRIO         1431655765
1356 
1357 extern const int sched_prio_to_weight[40];
1358 extern const u32 sched_prio_to_wmult[40];
1359 
1360 /*
1361  * {de,en}queue flags:
1362  *
1363  * DEQUEUE_SLEEP  - task is no longer runnable
1364  * ENQUEUE_WAKEUP - task just became runnable
1365  *
1366  * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
1367  *                are in a known state which allows modification. Such pairs
1368  *                should preserve as much state as possible.
1369  *
1370  * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
1371  *        in the runqueue.
1372  *
1373  * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
1374  * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
1375  * ENQUEUE_MIGRATED  - the task was migrated during wakeup
1376  *
1377  */
1378 
1379 #define DEQUEUE_SLEEP		0x01
1380 #define DEQUEUE_SAVE		0x02 /* matches ENQUEUE_RESTORE */
1381 #define DEQUEUE_MOVE		0x04 /* matches ENQUEUE_MOVE */
1382 #define DEQUEUE_NOCLOCK		0x08 /* matches ENQUEUE_NOCLOCK */
1383 
1384 #define ENQUEUE_WAKEUP		0x01
1385 #define ENQUEUE_RESTORE		0x02
1386 #define ENQUEUE_MOVE		0x04
1387 #define ENQUEUE_NOCLOCK		0x08
1388 
1389 #define ENQUEUE_HEAD		0x10
1390 #define ENQUEUE_REPLENISH	0x20
1391 #ifdef CONFIG_SMP
1392 #define ENQUEUE_MIGRATED	0x40
1393 #else
1394 #define ENQUEUE_MIGRATED	0x00
1395 #endif
1396 
1397 #define RETRY_TASK		((void *)-1UL)
1398 
1399 struct sched_class {
1400 	const struct sched_class *next;
1401 
1402 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1403 	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1404 	void (*yield_task) (struct rq *rq);
1405 	bool (*yield_to_task) (struct rq *rq, struct task_struct *p, bool preempt);
1406 
1407 	void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
1408 
1409 	/*
1410 	 * It is the responsibility of the pick_next_task() method that will
1411 	 * return the next task to call put_prev_task() on the @prev task or
1412 	 * something equivalent.
1413 	 *
1414 	 * May return RETRY_TASK when it finds a higher prio class has runnable
1415 	 * tasks.
1416 	 */
1417 	struct task_struct * (*pick_next_task) (struct rq *rq,
1418 						struct task_struct *prev,
1419 						struct rq_flags *rf);
1420 	void (*put_prev_task) (struct rq *rq, struct task_struct *p);
1421 
1422 #ifdef CONFIG_SMP
1423 	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
1424 	void (*migrate_task_rq)(struct task_struct *p);
1425 
1426 	void (*task_woken) (struct rq *this_rq, struct task_struct *task);
1427 
1428 	void (*set_cpus_allowed)(struct task_struct *p,
1429 				 const struct cpumask *newmask);
1430 
1431 	void (*rq_online)(struct rq *rq);
1432 	void (*rq_offline)(struct rq *rq);
1433 #endif
1434 
1435 	void (*set_curr_task) (struct rq *rq);
1436 	void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1437 	void (*task_fork) (struct task_struct *p);
1438 	void (*task_dead) (struct task_struct *p);
1439 
1440 	/*
1441 	 * The switched_from() call is allowed to drop rq->lock, therefore we
1442 	 * cannot assume the switched_from/switched_to pair is serliazed by
1443 	 * rq->lock. They are however serialized by p->pi_lock.
1444 	 */
1445 	void (*switched_from) (struct rq *this_rq, struct task_struct *task);
1446 	void (*switched_to) (struct rq *this_rq, struct task_struct *task);
1447 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1448 			     int oldprio);
1449 
1450 	unsigned int (*get_rr_interval) (struct rq *rq,
1451 					 struct task_struct *task);
1452 
1453 	void (*update_curr) (struct rq *rq);
1454 
1455 #define TASK_SET_GROUP  0
1456 #define TASK_MOVE_GROUP	1
1457 
1458 #ifdef CONFIG_FAIR_GROUP_SCHED
1459 	void (*task_change_group) (struct task_struct *p, int type);
1460 #endif
1461 };
1462 
1463 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
1464 {
1465 	prev->sched_class->put_prev_task(rq, prev);
1466 }
1467 
1468 static inline void set_curr_task(struct rq *rq, struct task_struct *curr)
1469 {
1470 	curr->sched_class->set_curr_task(rq);
1471 }
1472 
1473 #ifdef CONFIG_SMP
1474 #define sched_class_highest (&stop_sched_class)
1475 #else
1476 #define sched_class_highest (&dl_sched_class)
1477 #endif
1478 #define for_each_class(class) \
1479    for (class = sched_class_highest; class; class = class->next)
1480 
1481 extern const struct sched_class stop_sched_class;
1482 extern const struct sched_class dl_sched_class;
1483 extern const struct sched_class rt_sched_class;
1484 extern const struct sched_class fair_sched_class;
1485 extern const struct sched_class idle_sched_class;
1486 
1487 
1488 #ifdef CONFIG_SMP
1489 
1490 extern void update_group_capacity(struct sched_domain *sd, int cpu);
1491 
1492 extern void trigger_load_balance(struct rq *rq);
1493 
1494 extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask);
1495 
1496 #endif
1497 
1498 #ifdef CONFIG_CPU_IDLE
1499 static inline void idle_set_state(struct rq *rq,
1500 				  struct cpuidle_state *idle_state)
1501 {
1502 	rq->idle_state = idle_state;
1503 }
1504 
1505 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1506 {
1507 	SCHED_WARN_ON(!rcu_read_lock_held());
1508 	return rq->idle_state;
1509 }
1510 #else
1511 static inline void idle_set_state(struct rq *rq,
1512 				  struct cpuidle_state *idle_state)
1513 {
1514 }
1515 
1516 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1517 {
1518 	return NULL;
1519 }
1520 #endif
1521 
1522 extern void schedule_idle(void);
1523 
1524 extern void sysrq_sched_debug_show(void);
1525 extern void sched_init_granularity(void);
1526 extern void update_max_interval(void);
1527 
1528 extern void init_sched_dl_class(void);
1529 extern void init_sched_rt_class(void);
1530 extern void init_sched_fair_class(void);
1531 
1532 extern void resched_curr(struct rq *rq);
1533 extern void resched_cpu(int cpu);
1534 
1535 extern struct rt_bandwidth def_rt_bandwidth;
1536 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
1537 
1538 extern struct dl_bandwidth def_dl_bandwidth;
1539 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
1540 extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
1541 extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se);
1542 extern void init_dl_rq_bw_ratio(struct dl_rq *dl_rq);
1543 
1544 #define BW_SHIFT	20
1545 #define BW_UNIT		(1 << BW_SHIFT)
1546 #define RATIO_SHIFT	8
1547 unsigned long to_ratio(u64 period, u64 runtime);
1548 
1549 extern void init_entity_runnable_average(struct sched_entity *se);
1550 extern void post_init_entity_util_avg(struct sched_entity *se);
1551 
1552 #ifdef CONFIG_NO_HZ_FULL
1553 extern bool sched_can_stop_tick(struct rq *rq);
1554 
1555 /*
1556  * Tick may be needed by tasks in the runqueue depending on their policy and
1557  * requirements. If tick is needed, lets send the target an IPI to kick it out of
1558  * nohz mode if necessary.
1559  */
1560 static inline void sched_update_tick_dependency(struct rq *rq)
1561 {
1562 	int cpu;
1563 
1564 	if (!tick_nohz_full_enabled())
1565 		return;
1566 
1567 	cpu = cpu_of(rq);
1568 
1569 	if (!tick_nohz_full_cpu(cpu))
1570 		return;
1571 
1572 	if (sched_can_stop_tick(rq))
1573 		tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
1574 	else
1575 		tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
1576 }
1577 #else
1578 static inline void sched_update_tick_dependency(struct rq *rq) { }
1579 #endif
1580 
1581 static inline void add_nr_running(struct rq *rq, unsigned count)
1582 {
1583 	unsigned prev_nr = rq->nr_running;
1584 
1585 	rq->nr_running = prev_nr + count;
1586 
1587 	if (prev_nr < 2 && rq->nr_running >= 2) {
1588 #ifdef CONFIG_SMP
1589 		if (!rq->rd->overload)
1590 			rq->rd->overload = true;
1591 #endif
1592 	}
1593 
1594 	sched_update_tick_dependency(rq);
1595 }
1596 
1597 static inline void sub_nr_running(struct rq *rq, unsigned count)
1598 {
1599 	rq->nr_running -= count;
1600 	/* Check if we still need preemption */
1601 	sched_update_tick_dependency(rq);
1602 }
1603 
1604 static inline void rq_last_tick_reset(struct rq *rq)
1605 {
1606 #ifdef CONFIG_NO_HZ_FULL
1607 	rq->last_sched_tick = jiffies;
1608 #endif
1609 }
1610 
1611 extern void update_rq_clock(struct rq *rq);
1612 
1613 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
1614 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
1615 
1616 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
1617 
1618 extern const_debug unsigned int sysctl_sched_time_avg;
1619 extern const_debug unsigned int sysctl_sched_nr_migrate;
1620 extern const_debug unsigned int sysctl_sched_migration_cost;
1621 
1622 static inline u64 sched_avg_period(void)
1623 {
1624 	return (u64)sysctl_sched_time_avg * NSEC_PER_MSEC / 2;
1625 }
1626 
1627 #ifdef CONFIG_SCHED_HRTICK
1628 
1629 /*
1630  * Use hrtick when:
1631  *  - enabled by features
1632  *  - hrtimer is actually high res
1633  */
1634 static inline int hrtick_enabled(struct rq *rq)
1635 {
1636 	if (!sched_feat(HRTICK))
1637 		return 0;
1638 	if (!cpu_active(cpu_of(rq)))
1639 		return 0;
1640 	return hrtimer_is_hres_active(&rq->hrtick_timer);
1641 }
1642 
1643 void hrtick_start(struct rq *rq, u64 delay);
1644 
1645 #else
1646 
1647 static inline int hrtick_enabled(struct rq *rq)
1648 {
1649 	return 0;
1650 }
1651 
1652 #endif /* CONFIG_SCHED_HRTICK */
1653 
1654 #ifdef CONFIG_SMP
1655 extern void sched_avg_update(struct rq *rq);
1656 
1657 #ifndef arch_scale_freq_capacity
1658 static __always_inline
1659 unsigned long arch_scale_freq_capacity(struct sched_domain *sd, int cpu)
1660 {
1661 	return SCHED_CAPACITY_SCALE;
1662 }
1663 #endif
1664 
1665 #ifndef arch_scale_cpu_capacity
1666 static __always_inline
1667 unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu)
1668 {
1669 	if (sd && (sd->flags & SD_SHARE_CPUCAPACITY) && (sd->span_weight > 1))
1670 		return sd->smt_gain / sd->span_weight;
1671 
1672 	return SCHED_CAPACITY_SCALE;
1673 }
1674 #endif
1675 
1676 static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
1677 {
1678 	rq->rt_avg += rt_delta * arch_scale_freq_capacity(NULL, cpu_of(rq));
1679 	sched_avg_update(rq);
1680 }
1681 #else
1682 static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { }
1683 static inline void sched_avg_update(struct rq *rq) { }
1684 #endif
1685 
1686 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1687 	__acquires(rq->lock);
1688 
1689 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1690 	__acquires(p->pi_lock)
1691 	__acquires(rq->lock);
1692 
1693 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1694 	__releases(rq->lock)
1695 {
1696 	rq_unpin_lock(rq, rf);
1697 	raw_spin_unlock(&rq->lock);
1698 }
1699 
1700 static inline void
1701 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1702 	__releases(rq->lock)
1703 	__releases(p->pi_lock)
1704 {
1705 	rq_unpin_lock(rq, rf);
1706 	raw_spin_unlock(&rq->lock);
1707 	raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1708 }
1709 
1710 static inline void
1711 rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1712 	__acquires(rq->lock)
1713 {
1714 	raw_spin_lock_irqsave(&rq->lock, rf->flags);
1715 	rq_pin_lock(rq, rf);
1716 }
1717 
1718 static inline void
1719 rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1720 	__acquires(rq->lock)
1721 {
1722 	raw_spin_lock_irq(&rq->lock);
1723 	rq_pin_lock(rq, rf);
1724 }
1725 
1726 static inline void
1727 rq_lock(struct rq *rq, struct rq_flags *rf)
1728 	__acquires(rq->lock)
1729 {
1730 	raw_spin_lock(&rq->lock);
1731 	rq_pin_lock(rq, rf);
1732 }
1733 
1734 static inline void
1735 rq_relock(struct rq *rq, struct rq_flags *rf)
1736 	__acquires(rq->lock)
1737 {
1738 	raw_spin_lock(&rq->lock);
1739 	rq_repin_lock(rq, rf);
1740 }
1741 
1742 static inline void
1743 rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1744 	__releases(rq->lock)
1745 {
1746 	rq_unpin_lock(rq, rf);
1747 	raw_spin_unlock_irqrestore(&rq->lock, rf->flags);
1748 }
1749 
1750 static inline void
1751 rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1752 	__releases(rq->lock)
1753 {
1754 	rq_unpin_lock(rq, rf);
1755 	raw_spin_unlock_irq(&rq->lock);
1756 }
1757 
1758 static inline void
1759 rq_unlock(struct rq *rq, struct rq_flags *rf)
1760 	__releases(rq->lock)
1761 {
1762 	rq_unpin_lock(rq, rf);
1763 	raw_spin_unlock(&rq->lock);
1764 }
1765 
1766 #ifdef CONFIG_SMP
1767 #ifdef CONFIG_PREEMPT
1768 
1769 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2);
1770 
1771 /*
1772  * fair double_lock_balance: Safely acquires both rq->locks in a fair
1773  * way at the expense of forcing extra atomic operations in all
1774  * invocations.  This assures that the double_lock is acquired using the
1775  * same underlying policy as the spinlock_t on this architecture, which
1776  * reduces latency compared to the unfair variant below.  However, it
1777  * also adds more overhead and therefore may reduce throughput.
1778  */
1779 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1780 	__releases(this_rq->lock)
1781 	__acquires(busiest->lock)
1782 	__acquires(this_rq->lock)
1783 {
1784 	raw_spin_unlock(&this_rq->lock);
1785 	double_rq_lock(this_rq, busiest);
1786 
1787 	return 1;
1788 }
1789 
1790 #else
1791 /*
1792  * Unfair double_lock_balance: Optimizes throughput at the expense of
1793  * latency by eliminating extra atomic operations when the locks are
1794  * already in proper order on entry.  This favors lower cpu-ids and will
1795  * grant the double lock to lower cpus over higher ids under contention,
1796  * regardless of entry order into the function.
1797  */
1798 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1799 	__releases(this_rq->lock)
1800 	__acquires(busiest->lock)
1801 	__acquires(this_rq->lock)
1802 {
1803 	int ret = 0;
1804 
1805 	if (unlikely(!raw_spin_trylock(&busiest->lock))) {
1806 		if (busiest < this_rq) {
1807 			raw_spin_unlock(&this_rq->lock);
1808 			raw_spin_lock(&busiest->lock);
1809 			raw_spin_lock_nested(&this_rq->lock,
1810 					      SINGLE_DEPTH_NESTING);
1811 			ret = 1;
1812 		} else
1813 			raw_spin_lock_nested(&busiest->lock,
1814 					      SINGLE_DEPTH_NESTING);
1815 	}
1816 	return ret;
1817 }
1818 
1819 #endif /* CONFIG_PREEMPT */
1820 
1821 /*
1822  * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
1823  */
1824 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
1825 {
1826 	if (unlikely(!irqs_disabled())) {
1827 		/* printk() doesn't work good under rq->lock */
1828 		raw_spin_unlock(&this_rq->lock);
1829 		BUG_ON(1);
1830 	}
1831 
1832 	return _double_lock_balance(this_rq, busiest);
1833 }
1834 
1835 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
1836 	__releases(busiest->lock)
1837 {
1838 	raw_spin_unlock(&busiest->lock);
1839 	lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
1840 }
1841 
1842 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
1843 {
1844 	if (l1 > l2)
1845 		swap(l1, l2);
1846 
1847 	spin_lock(l1);
1848 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1849 }
1850 
1851 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
1852 {
1853 	if (l1 > l2)
1854 		swap(l1, l2);
1855 
1856 	spin_lock_irq(l1);
1857 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1858 }
1859 
1860 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
1861 {
1862 	if (l1 > l2)
1863 		swap(l1, l2);
1864 
1865 	raw_spin_lock(l1);
1866 	raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1867 }
1868 
1869 /*
1870  * double_rq_lock - safely lock two runqueues
1871  *
1872  * Note this does not disable interrupts like task_rq_lock,
1873  * you need to do so manually before calling.
1874  */
1875 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
1876 	__acquires(rq1->lock)
1877 	__acquires(rq2->lock)
1878 {
1879 	BUG_ON(!irqs_disabled());
1880 	if (rq1 == rq2) {
1881 		raw_spin_lock(&rq1->lock);
1882 		__acquire(rq2->lock);	/* Fake it out ;) */
1883 	} else {
1884 		if (rq1 < rq2) {
1885 			raw_spin_lock(&rq1->lock);
1886 			raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
1887 		} else {
1888 			raw_spin_lock(&rq2->lock);
1889 			raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
1890 		}
1891 	}
1892 }
1893 
1894 /*
1895  * double_rq_unlock - safely unlock two runqueues
1896  *
1897  * Note this does not restore interrupts like task_rq_unlock,
1898  * you need to do so manually after calling.
1899  */
1900 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
1901 	__releases(rq1->lock)
1902 	__releases(rq2->lock)
1903 {
1904 	raw_spin_unlock(&rq1->lock);
1905 	if (rq1 != rq2)
1906 		raw_spin_unlock(&rq2->lock);
1907 	else
1908 		__release(rq2->lock);
1909 }
1910 
1911 extern void set_rq_online (struct rq *rq);
1912 extern void set_rq_offline(struct rq *rq);
1913 extern bool sched_smp_initialized;
1914 
1915 #else /* CONFIG_SMP */
1916 
1917 /*
1918  * double_rq_lock - safely lock two runqueues
1919  *
1920  * Note this does not disable interrupts like task_rq_lock,
1921  * you need to do so manually before calling.
1922  */
1923 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
1924 	__acquires(rq1->lock)
1925 	__acquires(rq2->lock)
1926 {
1927 	BUG_ON(!irqs_disabled());
1928 	BUG_ON(rq1 != rq2);
1929 	raw_spin_lock(&rq1->lock);
1930 	__acquire(rq2->lock);	/* Fake it out ;) */
1931 }
1932 
1933 /*
1934  * double_rq_unlock - safely unlock two runqueues
1935  *
1936  * Note this does not restore interrupts like task_rq_unlock,
1937  * you need to do so manually after calling.
1938  */
1939 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
1940 	__releases(rq1->lock)
1941 	__releases(rq2->lock)
1942 {
1943 	BUG_ON(rq1 != rq2);
1944 	raw_spin_unlock(&rq1->lock);
1945 	__release(rq2->lock);
1946 }
1947 
1948 #endif
1949 
1950 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
1951 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
1952 
1953 #ifdef	CONFIG_SCHED_DEBUG
1954 extern bool sched_debug_enabled;
1955 
1956 extern void print_cfs_stats(struct seq_file *m, int cpu);
1957 extern void print_rt_stats(struct seq_file *m, int cpu);
1958 extern void print_dl_stats(struct seq_file *m, int cpu);
1959 extern void
1960 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
1961 #ifdef CONFIG_NUMA_BALANCING
1962 extern void
1963 show_numa_stats(struct task_struct *p, struct seq_file *m);
1964 extern void
1965 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
1966 	unsigned long tpf, unsigned long gsf, unsigned long gpf);
1967 #endif /* CONFIG_NUMA_BALANCING */
1968 #endif /* CONFIG_SCHED_DEBUG */
1969 
1970 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
1971 extern void init_rt_rq(struct rt_rq *rt_rq);
1972 extern void init_dl_rq(struct dl_rq *dl_rq);
1973 
1974 extern void cfs_bandwidth_usage_inc(void);
1975 extern void cfs_bandwidth_usage_dec(void);
1976 
1977 #ifdef CONFIG_NO_HZ_COMMON
1978 enum rq_nohz_flag_bits {
1979 	NOHZ_TICK_STOPPED,
1980 	NOHZ_BALANCE_KICK,
1981 };
1982 
1983 #define nohz_flags(cpu)	(&cpu_rq(cpu)->nohz_flags)
1984 
1985 extern void nohz_balance_exit_idle(unsigned int cpu);
1986 #else
1987 static inline void nohz_balance_exit_idle(unsigned int cpu) { }
1988 #endif
1989 
1990 
1991 #ifdef CONFIG_SMP
1992 static inline
1993 void __dl_update(struct dl_bw *dl_b, s64 bw)
1994 {
1995 	struct root_domain *rd = container_of(dl_b, struct root_domain, dl_bw);
1996 	int i;
1997 
1998 	RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
1999 			 "sched RCU must be held");
2000 	for_each_cpu_and(i, rd->span, cpu_active_mask) {
2001 		struct rq *rq = cpu_rq(i);
2002 
2003 		rq->dl.extra_bw += bw;
2004 	}
2005 }
2006 #else
2007 static inline
2008 void __dl_update(struct dl_bw *dl_b, s64 bw)
2009 {
2010 	struct dl_rq *dl = container_of(dl_b, struct dl_rq, dl_bw);
2011 
2012 	dl->extra_bw += bw;
2013 }
2014 #endif
2015 
2016 
2017 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2018 struct irqtime {
2019 	u64			total;
2020 	u64			tick_delta;
2021 	u64			irq_start_time;
2022 	struct u64_stats_sync	sync;
2023 };
2024 
2025 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
2026 
2027 /*
2028  * Returns the irqtime minus the softirq time computed by ksoftirqd.
2029  * Otherwise ksoftirqd's sum_exec_runtime is substracted its own runtime
2030  * and never move forward.
2031  */
2032 static inline u64 irq_time_read(int cpu)
2033 {
2034 	struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
2035 	unsigned int seq;
2036 	u64 total;
2037 
2038 	do {
2039 		seq = __u64_stats_fetch_begin(&irqtime->sync);
2040 		total = irqtime->total;
2041 	} while (__u64_stats_fetch_retry(&irqtime->sync, seq));
2042 
2043 	return total;
2044 }
2045 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
2046 
2047 #ifdef CONFIG_CPU_FREQ
2048 DECLARE_PER_CPU(struct update_util_data *, cpufreq_update_util_data);
2049 
2050 /**
2051  * cpufreq_update_util - Take a note about CPU utilization changes.
2052  * @rq: Runqueue to carry out the update for.
2053  * @flags: Update reason flags.
2054  *
2055  * This function is called by the scheduler on the CPU whose utilization is
2056  * being updated.
2057  *
2058  * It can only be called from RCU-sched read-side critical sections.
2059  *
2060  * The way cpufreq is currently arranged requires it to evaluate the CPU
2061  * performance state (frequency/voltage) on a regular basis to prevent it from
2062  * being stuck in a completely inadequate performance level for too long.
2063  * That is not guaranteed to happen if the updates are only triggered from CFS,
2064  * though, because they may not be coming in if RT or deadline tasks are active
2065  * all the time (or there are RT and DL tasks only).
2066  *
2067  * As a workaround for that issue, this function is called by the RT and DL
2068  * sched classes to trigger extra cpufreq updates to prevent it from stalling,
2069  * but that really is a band-aid.  Going forward it should be replaced with
2070  * solutions targeted more specifically at RT and DL tasks.
2071  */
2072 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
2073 {
2074 	struct update_util_data *data;
2075 
2076 	data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
2077 						  cpu_of(rq)));
2078 	if (data)
2079 		data->func(data, rq_clock(rq), flags);
2080 }
2081 #else
2082 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
2083 #endif /* CONFIG_CPU_FREQ */
2084 
2085 #ifdef arch_scale_freq_capacity
2086 #ifndef arch_scale_freq_invariant
2087 #define arch_scale_freq_invariant()	(true)
2088 #endif
2089 #else /* arch_scale_freq_capacity */
2090 #define arch_scale_freq_invariant()	(false)
2091 #endif
2092