xref: /openbmc/linux/kernel/sched/sched.h (revision 3557b3fd)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Scheduler internal types and methods:
4  */
5 #include <linux/sched.h>
6 
7 #include <linux/sched/autogroup.h>
8 #include <linux/sched/clock.h>
9 #include <linux/sched/coredump.h>
10 #include <linux/sched/cpufreq.h>
11 #include <linux/sched/cputime.h>
12 #include <linux/sched/deadline.h>
13 #include <linux/sched/debug.h>
14 #include <linux/sched/hotplug.h>
15 #include <linux/sched/idle.h>
16 #include <linux/sched/init.h>
17 #include <linux/sched/isolation.h>
18 #include <linux/sched/jobctl.h>
19 #include <linux/sched/loadavg.h>
20 #include <linux/sched/mm.h>
21 #include <linux/sched/nohz.h>
22 #include <linux/sched/numa_balancing.h>
23 #include <linux/sched/prio.h>
24 #include <linux/sched/rt.h>
25 #include <linux/sched/signal.h>
26 #include <linux/sched/smt.h>
27 #include <linux/sched/stat.h>
28 #include <linux/sched/sysctl.h>
29 #include <linux/sched/task.h>
30 #include <linux/sched/task_stack.h>
31 #include <linux/sched/topology.h>
32 #include <linux/sched/user.h>
33 #include <linux/sched/wake_q.h>
34 #include <linux/sched/xacct.h>
35 
36 #include <uapi/linux/sched/types.h>
37 
38 #include <linux/binfmts.h>
39 #include <linux/blkdev.h>
40 #include <linux/compat.h>
41 #include <linux/context_tracking.h>
42 #include <linux/cpufreq.h>
43 #include <linux/cpuidle.h>
44 #include <linux/cpuset.h>
45 #include <linux/ctype.h>
46 #include <linux/debugfs.h>
47 #include <linux/delayacct.h>
48 #include <linux/energy_model.h>
49 #include <linux/init_task.h>
50 #include <linux/kprobes.h>
51 #include <linux/kthread.h>
52 #include <linux/membarrier.h>
53 #include <linux/migrate.h>
54 #include <linux/mmu_context.h>
55 #include <linux/nmi.h>
56 #include <linux/proc_fs.h>
57 #include <linux/prefetch.h>
58 #include <linux/profile.h>
59 #include <linux/psi.h>
60 #include <linux/rcupdate_wait.h>
61 #include <linux/security.h>
62 #include <linux/stop_machine.h>
63 #include <linux/suspend.h>
64 #include <linux/swait.h>
65 #include <linux/syscalls.h>
66 #include <linux/task_work.h>
67 #include <linux/tsacct_kern.h>
68 
69 #include <asm/tlb.h>
70 
71 #ifdef CONFIG_PARAVIRT
72 # include <asm/paravirt.h>
73 #endif
74 
75 #include "cpupri.h"
76 #include "cpudeadline.h"
77 
78 #ifdef CONFIG_SCHED_DEBUG
79 # define SCHED_WARN_ON(x)	WARN_ONCE(x, #x)
80 #else
81 # define SCHED_WARN_ON(x)	({ (void)(x), 0; })
82 #endif
83 
84 struct rq;
85 struct cpuidle_state;
86 
87 /* task_struct::on_rq states: */
88 #define TASK_ON_RQ_QUEUED	1
89 #define TASK_ON_RQ_MIGRATING	2
90 
91 extern __read_mostly int scheduler_running;
92 
93 extern unsigned long calc_load_update;
94 extern atomic_long_t calc_load_tasks;
95 
96 extern void calc_global_load_tick(struct rq *this_rq);
97 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
98 
99 #ifdef CONFIG_SMP
100 extern void cpu_load_update_active(struct rq *this_rq);
101 #else
102 static inline void cpu_load_update_active(struct rq *this_rq) { }
103 #endif
104 
105 /*
106  * Helpers for converting nanosecond timing to jiffy resolution
107  */
108 #define NS_TO_JIFFIES(TIME)	((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
109 
110 /*
111  * Increase resolution of nice-level calculations for 64-bit architectures.
112  * The extra resolution improves shares distribution and load balancing of
113  * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
114  * hierarchies, especially on larger systems. This is not a user-visible change
115  * and does not change the user-interface for setting shares/weights.
116  *
117  * We increase resolution only if we have enough bits to allow this increased
118  * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
119  * are pretty high and the returns do not justify the increased costs.
120  *
121  * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
122  * increase coverage and consistency always enable it on 64-bit platforms.
123  */
124 #ifdef CONFIG_64BIT
125 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
126 # define scale_load(w)		((w) << SCHED_FIXEDPOINT_SHIFT)
127 # define scale_load_down(w)	((w) >> SCHED_FIXEDPOINT_SHIFT)
128 #else
129 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT)
130 # define scale_load(w)		(w)
131 # define scale_load_down(w)	(w)
132 #endif
133 
134 /*
135  * Task weight (visible to users) and its load (invisible to users) have
136  * independent resolution, but they should be well calibrated. We use
137  * scale_load() and scale_load_down(w) to convert between them. The
138  * following must be true:
139  *
140  *  scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD
141  *
142  */
143 #define NICE_0_LOAD		(1L << NICE_0_LOAD_SHIFT)
144 
145 /*
146  * Single value that decides SCHED_DEADLINE internal math precision.
147  * 10 -> just above 1us
148  * 9  -> just above 0.5us
149  */
150 #define DL_SCALE		10
151 
152 /*
153  * Single value that denotes runtime == period, ie unlimited time.
154  */
155 #define RUNTIME_INF		((u64)~0ULL)
156 
157 static inline int idle_policy(int policy)
158 {
159 	return policy == SCHED_IDLE;
160 }
161 static inline int fair_policy(int policy)
162 {
163 	return policy == SCHED_NORMAL || policy == SCHED_BATCH;
164 }
165 
166 static inline int rt_policy(int policy)
167 {
168 	return policy == SCHED_FIFO || policy == SCHED_RR;
169 }
170 
171 static inline int dl_policy(int policy)
172 {
173 	return policy == SCHED_DEADLINE;
174 }
175 static inline bool valid_policy(int policy)
176 {
177 	return idle_policy(policy) || fair_policy(policy) ||
178 		rt_policy(policy) || dl_policy(policy);
179 }
180 
181 static inline int task_has_idle_policy(struct task_struct *p)
182 {
183 	return idle_policy(p->policy);
184 }
185 
186 static inline int task_has_rt_policy(struct task_struct *p)
187 {
188 	return rt_policy(p->policy);
189 }
190 
191 static inline int task_has_dl_policy(struct task_struct *p)
192 {
193 	return dl_policy(p->policy);
194 }
195 
196 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
197 
198 /*
199  * !! For sched_setattr_nocheck() (kernel) only !!
200  *
201  * This is actually gross. :(
202  *
203  * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
204  * tasks, but still be able to sleep. We need this on platforms that cannot
205  * atomically change clock frequency. Remove once fast switching will be
206  * available on such platforms.
207  *
208  * SUGOV stands for SchedUtil GOVernor.
209  */
210 #define SCHED_FLAG_SUGOV	0x10000000
211 
212 static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se)
213 {
214 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
215 	return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
216 #else
217 	return false;
218 #endif
219 }
220 
221 /*
222  * Tells if entity @a should preempt entity @b.
223  */
224 static inline bool
225 dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
226 {
227 	return dl_entity_is_special(a) ||
228 	       dl_time_before(a->deadline, b->deadline);
229 }
230 
231 /*
232  * This is the priority-queue data structure of the RT scheduling class:
233  */
234 struct rt_prio_array {
235 	DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
236 	struct list_head queue[MAX_RT_PRIO];
237 };
238 
239 struct rt_bandwidth {
240 	/* nests inside the rq lock: */
241 	raw_spinlock_t		rt_runtime_lock;
242 	ktime_t			rt_period;
243 	u64			rt_runtime;
244 	struct hrtimer		rt_period_timer;
245 	unsigned int		rt_period_active;
246 };
247 
248 void __dl_clear_params(struct task_struct *p);
249 
250 /*
251  * To keep the bandwidth of -deadline tasks and groups under control
252  * we need some place where:
253  *  - store the maximum -deadline bandwidth of the system (the group);
254  *  - cache the fraction of that bandwidth that is currently allocated.
255  *
256  * This is all done in the data structure below. It is similar to the
257  * one used for RT-throttling (rt_bandwidth), with the main difference
258  * that, since here we are only interested in admission control, we
259  * do not decrease any runtime while the group "executes", neither we
260  * need a timer to replenish it.
261  *
262  * With respect to SMP, the bandwidth is given on a per-CPU basis,
263  * meaning that:
264  *  - dl_bw (< 100%) is the bandwidth of the system (group) on each CPU;
265  *  - dl_total_bw array contains, in the i-eth element, the currently
266  *    allocated bandwidth on the i-eth CPU.
267  * Moreover, groups consume bandwidth on each CPU, while tasks only
268  * consume bandwidth on the CPU they're running on.
269  * Finally, dl_total_bw_cpu is used to cache the index of dl_total_bw
270  * that will be shown the next time the proc or cgroup controls will
271  * be red. It on its turn can be changed by writing on its own
272  * control.
273  */
274 struct dl_bandwidth {
275 	raw_spinlock_t		dl_runtime_lock;
276 	u64			dl_runtime;
277 	u64			dl_period;
278 };
279 
280 static inline int dl_bandwidth_enabled(void)
281 {
282 	return sysctl_sched_rt_runtime >= 0;
283 }
284 
285 struct dl_bw {
286 	raw_spinlock_t		lock;
287 	u64			bw;
288 	u64			total_bw;
289 };
290 
291 static inline void __dl_update(struct dl_bw *dl_b, s64 bw);
292 
293 static inline
294 void __dl_sub(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
295 {
296 	dl_b->total_bw -= tsk_bw;
297 	__dl_update(dl_b, (s32)tsk_bw / cpus);
298 }
299 
300 static inline
301 void __dl_add(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
302 {
303 	dl_b->total_bw += tsk_bw;
304 	__dl_update(dl_b, -((s32)tsk_bw / cpus));
305 }
306 
307 static inline
308 bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw)
309 {
310 	return dl_b->bw != -1 &&
311 	       dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw;
312 }
313 
314 extern void dl_change_utilization(struct task_struct *p, u64 new_bw);
315 extern void init_dl_bw(struct dl_bw *dl_b);
316 extern int  sched_dl_global_validate(void);
317 extern void sched_dl_do_global(void);
318 extern int  sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
319 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
320 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
321 extern bool __checkparam_dl(const struct sched_attr *attr);
322 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
323 extern int  dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
324 extern int  dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
325 extern bool dl_cpu_busy(unsigned int cpu);
326 
327 #ifdef CONFIG_CGROUP_SCHED
328 
329 #include <linux/cgroup.h>
330 #include <linux/psi.h>
331 
332 struct cfs_rq;
333 struct rt_rq;
334 
335 extern struct list_head task_groups;
336 
337 struct cfs_bandwidth {
338 #ifdef CONFIG_CFS_BANDWIDTH
339 	raw_spinlock_t		lock;
340 	ktime_t			period;
341 	u64			quota;
342 	u64			runtime;
343 	s64			hierarchical_quota;
344 	u64			runtime_expires;
345 	int			expires_seq;
346 
347 	short			idle;
348 	short			period_active;
349 	struct hrtimer		period_timer;
350 	struct hrtimer		slack_timer;
351 	struct list_head	throttled_cfs_rq;
352 
353 	/* Statistics: */
354 	int			nr_periods;
355 	int			nr_throttled;
356 	u64			throttled_time;
357 
358 	bool                    distribute_running;
359 #endif
360 };
361 
362 /* Task group related information */
363 struct task_group {
364 	struct cgroup_subsys_state css;
365 
366 #ifdef CONFIG_FAIR_GROUP_SCHED
367 	/* schedulable entities of this group on each CPU */
368 	struct sched_entity	**se;
369 	/* runqueue "owned" by this group on each CPU */
370 	struct cfs_rq		**cfs_rq;
371 	unsigned long		shares;
372 
373 #ifdef	CONFIG_SMP
374 	/*
375 	 * load_avg can be heavily contended at clock tick time, so put
376 	 * it in its own cacheline separated from the fields above which
377 	 * will also be accessed at each tick.
378 	 */
379 	atomic_long_t		load_avg ____cacheline_aligned;
380 #endif
381 #endif
382 
383 #ifdef CONFIG_RT_GROUP_SCHED
384 	struct sched_rt_entity	**rt_se;
385 	struct rt_rq		**rt_rq;
386 
387 	struct rt_bandwidth	rt_bandwidth;
388 #endif
389 
390 	struct rcu_head		rcu;
391 	struct list_head	list;
392 
393 	struct task_group	*parent;
394 	struct list_head	siblings;
395 	struct list_head	children;
396 
397 #ifdef CONFIG_SCHED_AUTOGROUP
398 	struct autogroup	*autogroup;
399 #endif
400 
401 	struct cfs_bandwidth	cfs_bandwidth;
402 };
403 
404 #ifdef CONFIG_FAIR_GROUP_SCHED
405 #define ROOT_TASK_GROUP_LOAD	NICE_0_LOAD
406 
407 /*
408  * A weight of 0 or 1 can cause arithmetics problems.
409  * A weight of a cfs_rq is the sum of weights of which entities
410  * are queued on this cfs_rq, so a weight of a entity should not be
411  * too large, so as the shares value of a task group.
412  * (The default weight is 1024 - so there's no practical
413  *  limitation from this.)
414  */
415 #define MIN_SHARES		(1UL <<  1)
416 #define MAX_SHARES		(1UL << 18)
417 #endif
418 
419 typedef int (*tg_visitor)(struct task_group *, void *);
420 
421 extern int walk_tg_tree_from(struct task_group *from,
422 			     tg_visitor down, tg_visitor up, void *data);
423 
424 /*
425  * Iterate the full tree, calling @down when first entering a node and @up when
426  * leaving it for the final time.
427  *
428  * Caller must hold rcu_lock or sufficient equivalent.
429  */
430 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
431 {
432 	return walk_tg_tree_from(&root_task_group, down, up, data);
433 }
434 
435 extern int tg_nop(struct task_group *tg, void *data);
436 
437 extern void free_fair_sched_group(struct task_group *tg);
438 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
439 extern void online_fair_sched_group(struct task_group *tg);
440 extern void unregister_fair_sched_group(struct task_group *tg);
441 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
442 			struct sched_entity *se, int cpu,
443 			struct sched_entity *parent);
444 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
445 
446 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
447 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
448 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
449 
450 extern void free_rt_sched_group(struct task_group *tg);
451 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
452 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
453 		struct sched_rt_entity *rt_se, int cpu,
454 		struct sched_rt_entity *parent);
455 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
456 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
457 extern long sched_group_rt_runtime(struct task_group *tg);
458 extern long sched_group_rt_period(struct task_group *tg);
459 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
460 
461 extern struct task_group *sched_create_group(struct task_group *parent);
462 extern void sched_online_group(struct task_group *tg,
463 			       struct task_group *parent);
464 extern void sched_destroy_group(struct task_group *tg);
465 extern void sched_offline_group(struct task_group *tg);
466 
467 extern void sched_move_task(struct task_struct *tsk);
468 
469 #ifdef CONFIG_FAIR_GROUP_SCHED
470 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
471 
472 #ifdef CONFIG_SMP
473 extern void set_task_rq_fair(struct sched_entity *se,
474 			     struct cfs_rq *prev, struct cfs_rq *next);
475 #else /* !CONFIG_SMP */
476 static inline void set_task_rq_fair(struct sched_entity *se,
477 			     struct cfs_rq *prev, struct cfs_rq *next) { }
478 #endif /* CONFIG_SMP */
479 #endif /* CONFIG_FAIR_GROUP_SCHED */
480 
481 #else /* CONFIG_CGROUP_SCHED */
482 
483 struct cfs_bandwidth { };
484 
485 #endif	/* CONFIG_CGROUP_SCHED */
486 
487 /* CFS-related fields in a runqueue */
488 struct cfs_rq {
489 	struct load_weight	load;
490 	unsigned long		runnable_weight;
491 	unsigned int		nr_running;
492 	unsigned int		h_nr_running;
493 
494 	u64			exec_clock;
495 	u64			min_vruntime;
496 #ifndef CONFIG_64BIT
497 	u64			min_vruntime_copy;
498 #endif
499 
500 	struct rb_root_cached	tasks_timeline;
501 
502 	/*
503 	 * 'curr' points to currently running entity on this cfs_rq.
504 	 * It is set to NULL otherwise (i.e when none are currently running).
505 	 */
506 	struct sched_entity	*curr;
507 	struct sched_entity	*next;
508 	struct sched_entity	*last;
509 	struct sched_entity	*skip;
510 
511 #ifdef	CONFIG_SCHED_DEBUG
512 	unsigned int		nr_spread_over;
513 #endif
514 
515 #ifdef CONFIG_SMP
516 	/*
517 	 * CFS load tracking
518 	 */
519 	struct sched_avg	avg;
520 #ifndef CONFIG_64BIT
521 	u64			load_last_update_time_copy;
522 #endif
523 	struct {
524 		raw_spinlock_t	lock ____cacheline_aligned;
525 		int		nr;
526 		unsigned long	load_avg;
527 		unsigned long	util_avg;
528 		unsigned long	runnable_sum;
529 	} removed;
530 
531 #ifdef CONFIG_FAIR_GROUP_SCHED
532 	unsigned long		tg_load_avg_contrib;
533 	long			propagate;
534 	long			prop_runnable_sum;
535 
536 	/*
537 	 *   h_load = weight * f(tg)
538 	 *
539 	 * Where f(tg) is the recursive weight fraction assigned to
540 	 * this group.
541 	 */
542 	unsigned long		h_load;
543 	u64			last_h_load_update;
544 	struct sched_entity	*h_load_next;
545 #endif /* CONFIG_FAIR_GROUP_SCHED */
546 #endif /* CONFIG_SMP */
547 
548 #ifdef CONFIG_FAIR_GROUP_SCHED
549 	struct rq		*rq;	/* CPU runqueue to which this cfs_rq is attached */
550 
551 	/*
552 	 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
553 	 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
554 	 * (like users, containers etc.)
555 	 *
556 	 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
557 	 * This list is used during load balance.
558 	 */
559 	int			on_list;
560 	struct list_head	leaf_cfs_rq_list;
561 	struct task_group	*tg;	/* group that "owns" this runqueue */
562 
563 #ifdef CONFIG_CFS_BANDWIDTH
564 	int			runtime_enabled;
565 	int			expires_seq;
566 	u64			runtime_expires;
567 	s64			runtime_remaining;
568 
569 	u64			throttled_clock;
570 	u64			throttled_clock_task;
571 	u64			throttled_clock_task_time;
572 	int			throttled;
573 	int			throttle_count;
574 	struct list_head	throttled_list;
575 #endif /* CONFIG_CFS_BANDWIDTH */
576 #endif /* CONFIG_FAIR_GROUP_SCHED */
577 };
578 
579 static inline int rt_bandwidth_enabled(void)
580 {
581 	return sysctl_sched_rt_runtime >= 0;
582 }
583 
584 /* RT IPI pull logic requires IRQ_WORK */
585 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
586 # define HAVE_RT_PUSH_IPI
587 #endif
588 
589 /* Real-Time classes' related field in a runqueue: */
590 struct rt_rq {
591 	struct rt_prio_array	active;
592 	unsigned int		rt_nr_running;
593 	unsigned int		rr_nr_running;
594 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
595 	struct {
596 		int		curr; /* highest queued rt task prio */
597 #ifdef CONFIG_SMP
598 		int		next; /* next highest */
599 #endif
600 	} highest_prio;
601 #endif
602 #ifdef CONFIG_SMP
603 	unsigned long		rt_nr_migratory;
604 	unsigned long		rt_nr_total;
605 	int			overloaded;
606 	struct plist_head	pushable_tasks;
607 
608 #endif /* CONFIG_SMP */
609 	int			rt_queued;
610 
611 	int			rt_throttled;
612 	u64			rt_time;
613 	u64			rt_runtime;
614 	/* Nests inside the rq lock: */
615 	raw_spinlock_t		rt_runtime_lock;
616 
617 #ifdef CONFIG_RT_GROUP_SCHED
618 	unsigned long		rt_nr_boosted;
619 
620 	struct rq		*rq;
621 	struct task_group	*tg;
622 #endif
623 };
624 
625 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
626 {
627 	return rt_rq->rt_queued && rt_rq->rt_nr_running;
628 }
629 
630 /* Deadline class' related fields in a runqueue */
631 struct dl_rq {
632 	/* runqueue is an rbtree, ordered by deadline */
633 	struct rb_root_cached	root;
634 
635 	unsigned long		dl_nr_running;
636 
637 #ifdef CONFIG_SMP
638 	/*
639 	 * Deadline values of the currently executing and the
640 	 * earliest ready task on this rq. Caching these facilitates
641 	 * the decision whether or not a ready but not running task
642 	 * should migrate somewhere else.
643 	 */
644 	struct {
645 		u64		curr;
646 		u64		next;
647 	} earliest_dl;
648 
649 	unsigned long		dl_nr_migratory;
650 	int			overloaded;
651 
652 	/*
653 	 * Tasks on this rq that can be pushed away. They are kept in
654 	 * an rb-tree, ordered by tasks' deadlines, with caching
655 	 * of the leftmost (earliest deadline) element.
656 	 */
657 	struct rb_root_cached	pushable_dl_tasks_root;
658 #else
659 	struct dl_bw		dl_bw;
660 #endif
661 	/*
662 	 * "Active utilization" for this runqueue: increased when a
663 	 * task wakes up (becomes TASK_RUNNING) and decreased when a
664 	 * task blocks
665 	 */
666 	u64			running_bw;
667 
668 	/*
669 	 * Utilization of the tasks "assigned" to this runqueue (including
670 	 * the tasks that are in runqueue and the tasks that executed on this
671 	 * CPU and blocked). Increased when a task moves to this runqueue, and
672 	 * decreased when the task moves away (migrates, changes scheduling
673 	 * policy, or terminates).
674 	 * This is needed to compute the "inactive utilization" for the
675 	 * runqueue (inactive utilization = this_bw - running_bw).
676 	 */
677 	u64			this_bw;
678 	u64			extra_bw;
679 
680 	/*
681 	 * Inverse of the fraction of CPU utilization that can be reclaimed
682 	 * by the GRUB algorithm.
683 	 */
684 	u64			bw_ratio;
685 };
686 
687 #ifdef CONFIG_FAIR_GROUP_SCHED
688 /* An entity is a task if it doesn't "own" a runqueue */
689 #define entity_is_task(se)	(!se->my_q)
690 #else
691 #define entity_is_task(se)	1
692 #endif
693 
694 #ifdef CONFIG_SMP
695 /*
696  * XXX we want to get rid of these helpers and use the full load resolution.
697  */
698 static inline long se_weight(struct sched_entity *se)
699 {
700 	return scale_load_down(se->load.weight);
701 }
702 
703 static inline long se_runnable(struct sched_entity *se)
704 {
705 	return scale_load_down(se->runnable_weight);
706 }
707 
708 static inline bool sched_asym_prefer(int a, int b)
709 {
710 	return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
711 }
712 
713 struct perf_domain {
714 	struct em_perf_domain *em_pd;
715 	struct perf_domain *next;
716 	struct rcu_head rcu;
717 };
718 
719 /* Scheduling group status flags */
720 #define SG_OVERLOAD		0x1 /* More than one runnable task on a CPU. */
721 #define SG_OVERUTILIZED		0x2 /* One or more CPUs are over-utilized. */
722 
723 /*
724  * We add the notion of a root-domain which will be used to define per-domain
725  * variables. Each exclusive cpuset essentially defines an island domain by
726  * fully partitioning the member CPUs from any other cpuset. Whenever a new
727  * exclusive cpuset is created, we also create and attach a new root-domain
728  * object.
729  *
730  */
731 struct root_domain {
732 	atomic_t		refcount;
733 	atomic_t		rto_count;
734 	struct rcu_head		rcu;
735 	cpumask_var_t		span;
736 	cpumask_var_t		online;
737 
738 	/*
739 	 * Indicate pullable load on at least one CPU, e.g:
740 	 * - More than one runnable task
741 	 * - Running task is misfit
742 	 */
743 	int			overload;
744 
745 	/* Indicate one or more cpus over-utilized (tipping point) */
746 	int			overutilized;
747 
748 	/*
749 	 * The bit corresponding to a CPU gets set here if such CPU has more
750 	 * than one runnable -deadline task (as it is below for RT tasks).
751 	 */
752 	cpumask_var_t		dlo_mask;
753 	atomic_t		dlo_count;
754 	struct dl_bw		dl_bw;
755 	struct cpudl		cpudl;
756 
757 #ifdef HAVE_RT_PUSH_IPI
758 	/*
759 	 * For IPI pull requests, loop across the rto_mask.
760 	 */
761 	struct irq_work		rto_push_work;
762 	raw_spinlock_t		rto_lock;
763 	/* These are only updated and read within rto_lock */
764 	int			rto_loop;
765 	int			rto_cpu;
766 	/* These atomics are updated outside of a lock */
767 	atomic_t		rto_loop_next;
768 	atomic_t		rto_loop_start;
769 #endif
770 	/*
771 	 * The "RT overload" flag: it gets set if a CPU has more than
772 	 * one runnable RT task.
773 	 */
774 	cpumask_var_t		rto_mask;
775 	struct cpupri		cpupri;
776 
777 	unsigned long		max_cpu_capacity;
778 
779 	/*
780 	 * NULL-terminated list of performance domains intersecting with the
781 	 * CPUs of the rd. Protected by RCU.
782 	 */
783 	struct perf_domain	*pd;
784 };
785 
786 extern struct root_domain def_root_domain;
787 extern struct mutex sched_domains_mutex;
788 
789 extern void init_defrootdomain(void);
790 extern int sched_init_domains(const struct cpumask *cpu_map);
791 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
792 extern void sched_get_rd(struct root_domain *rd);
793 extern void sched_put_rd(struct root_domain *rd);
794 
795 #ifdef HAVE_RT_PUSH_IPI
796 extern void rto_push_irq_work_func(struct irq_work *work);
797 #endif
798 #endif /* CONFIG_SMP */
799 
800 /*
801  * This is the main, per-CPU runqueue data structure.
802  *
803  * Locking rule: those places that want to lock multiple runqueues
804  * (such as the load balancing or the thread migration code), lock
805  * acquire operations must be ordered by ascending &runqueue.
806  */
807 struct rq {
808 	/* runqueue lock: */
809 	raw_spinlock_t		lock;
810 
811 	/*
812 	 * nr_running and cpu_load should be in the same cacheline because
813 	 * remote CPUs use both these fields when doing load calculation.
814 	 */
815 	unsigned int		nr_running;
816 #ifdef CONFIG_NUMA_BALANCING
817 	unsigned int		nr_numa_running;
818 	unsigned int		nr_preferred_running;
819 	unsigned int		numa_migrate_on;
820 #endif
821 	#define CPU_LOAD_IDX_MAX 5
822 	unsigned long		cpu_load[CPU_LOAD_IDX_MAX];
823 #ifdef CONFIG_NO_HZ_COMMON
824 #ifdef CONFIG_SMP
825 	unsigned long		last_load_update_tick;
826 	unsigned long		last_blocked_load_update_tick;
827 	unsigned int		has_blocked_load;
828 #endif /* CONFIG_SMP */
829 	unsigned int		nohz_tick_stopped;
830 	atomic_t nohz_flags;
831 #endif /* CONFIG_NO_HZ_COMMON */
832 
833 	/* capture load from *all* tasks on this CPU: */
834 	struct load_weight	load;
835 	unsigned long		nr_load_updates;
836 	u64			nr_switches;
837 
838 	struct cfs_rq		cfs;
839 	struct rt_rq		rt;
840 	struct dl_rq		dl;
841 
842 #ifdef CONFIG_FAIR_GROUP_SCHED
843 	/* list of leaf cfs_rq on this CPU: */
844 	struct list_head	leaf_cfs_rq_list;
845 	struct list_head	*tmp_alone_branch;
846 #endif /* CONFIG_FAIR_GROUP_SCHED */
847 
848 	/*
849 	 * This is part of a global counter where only the total sum
850 	 * over all CPUs matters. A task can increase this counter on
851 	 * one CPU and if it got migrated afterwards it may decrease
852 	 * it on another CPU. Always updated under the runqueue lock:
853 	 */
854 	unsigned long		nr_uninterruptible;
855 
856 	struct task_struct	*curr;
857 	struct task_struct	*idle;
858 	struct task_struct	*stop;
859 	unsigned long		next_balance;
860 	struct mm_struct	*prev_mm;
861 
862 	unsigned int		clock_update_flags;
863 	u64			clock;
864 	/* Ensure that all clocks are in the same cache line */
865 	u64			clock_task ____cacheline_aligned;
866 	u64			clock_pelt;
867 	unsigned long		lost_idle_time;
868 
869 	atomic_t		nr_iowait;
870 
871 #ifdef CONFIG_SMP
872 	struct root_domain	*rd;
873 	struct sched_domain	*sd;
874 
875 	unsigned long		cpu_capacity;
876 	unsigned long		cpu_capacity_orig;
877 
878 	struct callback_head	*balance_callback;
879 
880 	unsigned char		idle_balance;
881 
882 	unsigned long		misfit_task_load;
883 
884 	/* For active balancing */
885 	int			active_balance;
886 	int			push_cpu;
887 	struct cpu_stop_work	active_balance_work;
888 
889 	/* CPU of this runqueue: */
890 	int			cpu;
891 	int			online;
892 
893 	struct list_head cfs_tasks;
894 
895 	struct sched_avg	avg_rt;
896 	struct sched_avg	avg_dl;
897 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
898 	struct sched_avg	avg_irq;
899 #endif
900 	u64			idle_stamp;
901 	u64			avg_idle;
902 
903 	/* This is used to determine avg_idle's max value */
904 	u64			max_idle_balance_cost;
905 #endif
906 
907 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
908 	u64			prev_irq_time;
909 #endif
910 #ifdef CONFIG_PARAVIRT
911 	u64			prev_steal_time;
912 #endif
913 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
914 	u64			prev_steal_time_rq;
915 #endif
916 
917 	/* calc_load related fields */
918 	unsigned long		calc_load_update;
919 	long			calc_load_active;
920 
921 #ifdef CONFIG_SCHED_HRTICK
922 #ifdef CONFIG_SMP
923 	int			hrtick_csd_pending;
924 	call_single_data_t	hrtick_csd;
925 #endif
926 	struct hrtimer		hrtick_timer;
927 #endif
928 
929 #ifdef CONFIG_SCHEDSTATS
930 	/* latency stats */
931 	struct sched_info	rq_sched_info;
932 	unsigned long long	rq_cpu_time;
933 	/* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
934 
935 	/* sys_sched_yield() stats */
936 	unsigned int		yld_count;
937 
938 	/* schedule() stats */
939 	unsigned int		sched_count;
940 	unsigned int		sched_goidle;
941 
942 	/* try_to_wake_up() stats */
943 	unsigned int		ttwu_count;
944 	unsigned int		ttwu_local;
945 #endif
946 
947 #ifdef CONFIG_SMP
948 	struct llist_head	wake_list;
949 #endif
950 
951 #ifdef CONFIG_CPU_IDLE
952 	/* Must be inspected within a rcu lock section */
953 	struct cpuidle_state	*idle_state;
954 #endif
955 };
956 
957 #ifdef CONFIG_FAIR_GROUP_SCHED
958 
959 /* CPU runqueue to which this cfs_rq is attached */
960 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
961 {
962 	return cfs_rq->rq;
963 }
964 
965 #else
966 
967 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
968 {
969 	return container_of(cfs_rq, struct rq, cfs);
970 }
971 #endif
972 
973 static inline int cpu_of(struct rq *rq)
974 {
975 #ifdef CONFIG_SMP
976 	return rq->cpu;
977 #else
978 	return 0;
979 #endif
980 }
981 
982 
983 #ifdef CONFIG_SCHED_SMT
984 extern void __update_idle_core(struct rq *rq);
985 
986 static inline void update_idle_core(struct rq *rq)
987 {
988 	if (static_branch_unlikely(&sched_smt_present))
989 		__update_idle_core(rq);
990 }
991 
992 #else
993 static inline void update_idle_core(struct rq *rq) { }
994 #endif
995 
996 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
997 
998 #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
999 #define this_rq()		this_cpu_ptr(&runqueues)
1000 #define task_rq(p)		cpu_rq(task_cpu(p))
1001 #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
1002 #define raw_rq()		raw_cpu_ptr(&runqueues)
1003 
1004 extern void update_rq_clock(struct rq *rq);
1005 
1006 static inline u64 __rq_clock_broken(struct rq *rq)
1007 {
1008 	return READ_ONCE(rq->clock);
1009 }
1010 
1011 /*
1012  * rq::clock_update_flags bits
1013  *
1014  * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1015  *  call to __schedule(). This is an optimisation to avoid
1016  *  neighbouring rq clock updates.
1017  *
1018  * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1019  *  in effect and calls to update_rq_clock() are being ignored.
1020  *
1021  * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1022  *  made to update_rq_clock() since the last time rq::lock was pinned.
1023  *
1024  * If inside of __schedule(), clock_update_flags will have been
1025  * shifted left (a left shift is a cheap operation for the fast path
1026  * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1027  *
1028  *	if (rq-clock_update_flags >= RQCF_UPDATED)
1029  *
1030  * to check if %RQCF_UPADTED is set. It'll never be shifted more than
1031  * one position though, because the next rq_unpin_lock() will shift it
1032  * back.
1033  */
1034 #define RQCF_REQ_SKIP		0x01
1035 #define RQCF_ACT_SKIP		0x02
1036 #define RQCF_UPDATED		0x04
1037 
1038 static inline void assert_clock_updated(struct rq *rq)
1039 {
1040 	/*
1041 	 * The only reason for not seeing a clock update since the
1042 	 * last rq_pin_lock() is if we're currently skipping updates.
1043 	 */
1044 	SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
1045 }
1046 
1047 static inline u64 rq_clock(struct rq *rq)
1048 {
1049 	lockdep_assert_held(&rq->lock);
1050 	assert_clock_updated(rq);
1051 
1052 	return rq->clock;
1053 }
1054 
1055 static inline u64 rq_clock_task(struct rq *rq)
1056 {
1057 	lockdep_assert_held(&rq->lock);
1058 	assert_clock_updated(rq);
1059 
1060 	return rq->clock_task;
1061 }
1062 
1063 static inline void rq_clock_skip_update(struct rq *rq)
1064 {
1065 	lockdep_assert_held(&rq->lock);
1066 	rq->clock_update_flags |= RQCF_REQ_SKIP;
1067 }
1068 
1069 /*
1070  * See rt task throttling, which is the only time a skip
1071  * request is cancelled.
1072  */
1073 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1074 {
1075 	lockdep_assert_held(&rq->lock);
1076 	rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1077 }
1078 
1079 struct rq_flags {
1080 	unsigned long flags;
1081 	struct pin_cookie cookie;
1082 #ifdef CONFIG_SCHED_DEBUG
1083 	/*
1084 	 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1085 	 * current pin context is stashed here in case it needs to be
1086 	 * restored in rq_repin_lock().
1087 	 */
1088 	unsigned int clock_update_flags;
1089 #endif
1090 };
1091 
1092 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1093 {
1094 	rf->cookie = lockdep_pin_lock(&rq->lock);
1095 
1096 #ifdef CONFIG_SCHED_DEBUG
1097 	rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1098 	rf->clock_update_flags = 0;
1099 #endif
1100 }
1101 
1102 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1103 {
1104 #ifdef CONFIG_SCHED_DEBUG
1105 	if (rq->clock_update_flags > RQCF_ACT_SKIP)
1106 		rf->clock_update_flags = RQCF_UPDATED;
1107 #endif
1108 
1109 	lockdep_unpin_lock(&rq->lock, rf->cookie);
1110 }
1111 
1112 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1113 {
1114 	lockdep_repin_lock(&rq->lock, rf->cookie);
1115 
1116 #ifdef CONFIG_SCHED_DEBUG
1117 	/*
1118 	 * Restore the value we stashed in @rf for this pin context.
1119 	 */
1120 	rq->clock_update_flags |= rf->clock_update_flags;
1121 #endif
1122 }
1123 
1124 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1125 	__acquires(rq->lock);
1126 
1127 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1128 	__acquires(p->pi_lock)
1129 	__acquires(rq->lock);
1130 
1131 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1132 	__releases(rq->lock)
1133 {
1134 	rq_unpin_lock(rq, rf);
1135 	raw_spin_unlock(&rq->lock);
1136 }
1137 
1138 static inline void
1139 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1140 	__releases(rq->lock)
1141 	__releases(p->pi_lock)
1142 {
1143 	rq_unpin_lock(rq, rf);
1144 	raw_spin_unlock(&rq->lock);
1145 	raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1146 }
1147 
1148 static inline void
1149 rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1150 	__acquires(rq->lock)
1151 {
1152 	raw_spin_lock_irqsave(&rq->lock, rf->flags);
1153 	rq_pin_lock(rq, rf);
1154 }
1155 
1156 static inline void
1157 rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1158 	__acquires(rq->lock)
1159 {
1160 	raw_spin_lock_irq(&rq->lock);
1161 	rq_pin_lock(rq, rf);
1162 }
1163 
1164 static inline void
1165 rq_lock(struct rq *rq, struct rq_flags *rf)
1166 	__acquires(rq->lock)
1167 {
1168 	raw_spin_lock(&rq->lock);
1169 	rq_pin_lock(rq, rf);
1170 }
1171 
1172 static inline void
1173 rq_relock(struct rq *rq, struct rq_flags *rf)
1174 	__acquires(rq->lock)
1175 {
1176 	raw_spin_lock(&rq->lock);
1177 	rq_repin_lock(rq, rf);
1178 }
1179 
1180 static inline void
1181 rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1182 	__releases(rq->lock)
1183 {
1184 	rq_unpin_lock(rq, rf);
1185 	raw_spin_unlock_irqrestore(&rq->lock, rf->flags);
1186 }
1187 
1188 static inline void
1189 rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1190 	__releases(rq->lock)
1191 {
1192 	rq_unpin_lock(rq, rf);
1193 	raw_spin_unlock_irq(&rq->lock);
1194 }
1195 
1196 static inline void
1197 rq_unlock(struct rq *rq, struct rq_flags *rf)
1198 	__releases(rq->lock)
1199 {
1200 	rq_unpin_lock(rq, rf);
1201 	raw_spin_unlock(&rq->lock);
1202 }
1203 
1204 static inline struct rq *
1205 this_rq_lock_irq(struct rq_flags *rf)
1206 	__acquires(rq->lock)
1207 {
1208 	struct rq *rq;
1209 
1210 	local_irq_disable();
1211 	rq = this_rq();
1212 	rq_lock(rq, rf);
1213 	return rq;
1214 }
1215 
1216 #ifdef CONFIG_NUMA
1217 enum numa_topology_type {
1218 	NUMA_DIRECT,
1219 	NUMA_GLUELESS_MESH,
1220 	NUMA_BACKPLANE,
1221 };
1222 extern enum numa_topology_type sched_numa_topology_type;
1223 extern int sched_max_numa_distance;
1224 extern bool find_numa_distance(int distance);
1225 #endif
1226 
1227 #ifdef CONFIG_NUMA
1228 extern void sched_init_numa(void);
1229 extern void sched_domains_numa_masks_set(unsigned int cpu);
1230 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1231 #else
1232 static inline void sched_init_numa(void) { }
1233 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
1234 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1235 #endif
1236 
1237 #ifdef CONFIG_NUMA_BALANCING
1238 /* The regions in numa_faults array from task_struct */
1239 enum numa_faults_stats {
1240 	NUMA_MEM = 0,
1241 	NUMA_CPU,
1242 	NUMA_MEMBUF,
1243 	NUMA_CPUBUF
1244 };
1245 extern void sched_setnuma(struct task_struct *p, int node);
1246 extern int migrate_task_to(struct task_struct *p, int cpu);
1247 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1248 			int cpu, int scpu);
1249 extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1250 #else
1251 static inline void
1252 init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1253 {
1254 }
1255 #endif /* CONFIG_NUMA_BALANCING */
1256 
1257 #ifdef CONFIG_SMP
1258 
1259 static inline void
1260 queue_balance_callback(struct rq *rq,
1261 		       struct callback_head *head,
1262 		       void (*func)(struct rq *rq))
1263 {
1264 	lockdep_assert_held(&rq->lock);
1265 
1266 	if (unlikely(head->next))
1267 		return;
1268 
1269 	head->func = (void (*)(struct callback_head *))func;
1270 	head->next = rq->balance_callback;
1271 	rq->balance_callback = head;
1272 }
1273 
1274 extern void sched_ttwu_pending(void);
1275 
1276 #define rcu_dereference_check_sched_domain(p) \
1277 	rcu_dereference_check((p), \
1278 			      lockdep_is_held(&sched_domains_mutex))
1279 
1280 /*
1281  * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1282  * See destroy_sched_domains: call_rcu for details.
1283  *
1284  * The domain tree of any CPU may only be accessed from within
1285  * preempt-disabled sections.
1286  */
1287 #define for_each_domain(cpu, __sd) \
1288 	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1289 			__sd; __sd = __sd->parent)
1290 
1291 #define for_each_lower_domain(sd) for (; sd; sd = sd->child)
1292 
1293 /**
1294  * highest_flag_domain - Return highest sched_domain containing flag.
1295  * @cpu:	The CPU whose highest level of sched domain is to
1296  *		be returned.
1297  * @flag:	The flag to check for the highest sched_domain
1298  *		for the given CPU.
1299  *
1300  * Returns the highest sched_domain of a CPU which contains the given flag.
1301  */
1302 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1303 {
1304 	struct sched_domain *sd, *hsd = NULL;
1305 
1306 	for_each_domain(cpu, sd) {
1307 		if (!(sd->flags & flag))
1308 			break;
1309 		hsd = sd;
1310 	}
1311 
1312 	return hsd;
1313 }
1314 
1315 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1316 {
1317 	struct sched_domain *sd;
1318 
1319 	for_each_domain(cpu, sd) {
1320 		if (sd->flags & flag)
1321 			break;
1322 	}
1323 
1324 	return sd;
1325 }
1326 
1327 DECLARE_PER_CPU(struct sched_domain *, sd_llc);
1328 DECLARE_PER_CPU(int, sd_llc_size);
1329 DECLARE_PER_CPU(int, sd_llc_id);
1330 DECLARE_PER_CPU(struct sched_domain_shared *, sd_llc_shared);
1331 DECLARE_PER_CPU(struct sched_domain *, sd_numa);
1332 DECLARE_PER_CPU(struct sched_domain *, sd_asym_packing);
1333 DECLARE_PER_CPU(struct sched_domain *, sd_asym_cpucapacity);
1334 extern struct static_key_false sched_asym_cpucapacity;
1335 
1336 struct sched_group_capacity {
1337 	atomic_t		ref;
1338 	/*
1339 	 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
1340 	 * for a single CPU.
1341 	 */
1342 	unsigned long		capacity;
1343 	unsigned long		min_capacity;		/* Min per-CPU capacity in group */
1344 	unsigned long		max_capacity;		/* Max per-CPU capacity in group */
1345 	unsigned long		next_update;
1346 	int			imbalance;		/* XXX unrelated to capacity but shared group state */
1347 
1348 #ifdef CONFIG_SCHED_DEBUG
1349 	int			id;
1350 #endif
1351 
1352 	unsigned long		cpumask[0];		/* Balance mask */
1353 };
1354 
1355 struct sched_group {
1356 	struct sched_group	*next;			/* Must be a circular list */
1357 	atomic_t		ref;
1358 
1359 	unsigned int		group_weight;
1360 	struct sched_group_capacity *sgc;
1361 	int			asym_prefer_cpu;	/* CPU of highest priority in group */
1362 
1363 	/*
1364 	 * The CPUs this group covers.
1365 	 *
1366 	 * NOTE: this field is variable length. (Allocated dynamically
1367 	 * by attaching extra space to the end of the structure,
1368 	 * depending on how many CPUs the kernel has booted up with)
1369 	 */
1370 	unsigned long		cpumask[0];
1371 };
1372 
1373 static inline struct cpumask *sched_group_span(struct sched_group *sg)
1374 {
1375 	return to_cpumask(sg->cpumask);
1376 }
1377 
1378 /*
1379  * See build_balance_mask().
1380  */
1381 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
1382 {
1383 	return to_cpumask(sg->sgc->cpumask);
1384 }
1385 
1386 /**
1387  * group_first_cpu - Returns the first CPU in the cpumask of a sched_group.
1388  * @group: The group whose first CPU is to be returned.
1389  */
1390 static inline unsigned int group_first_cpu(struct sched_group *group)
1391 {
1392 	return cpumask_first(sched_group_span(group));
1393 }
1394 
1395 extern int group_balance_cpu(struct sched_group *sg);
1396 
1397 #if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
1398 void register_sched_domain_sysctl(void);
1399 void dirty_sched_domain_sysctl(int cpu);
1400 void unregister_sched_domain_sysctl(void);
1401 #else
1402 static inline void register_sched_domain_sysctl(void)
1403 {
1404 }
1405 static inline void dirty_sched_domain_sysctl(int cpu)
1406 {
1407 }
1408 static inline void unregister_sched_domain_sysctl(void)
1409 {
1410 }
1411 #endif
1412 
1413 #else
1414 
1415 static inline void sched_ttwu_pending(void) { }
1416 
1417 #endif /* CONFIG_SMP */
1418 
1419 #include "stats.h"
1420 #include "autogroup.h"
1421 
1422 #ifdef CONFIG_CGROUP_SCHED
1423 
1424 /*
1425  * Return the group to which this tasks belongs.
1426  *
1427  * We cannot use task_css() and friends because the cgroup subsystem
1428  * changes that value before the cgroup_subsys::attach() method is called,
1429  * therefore we cannot pin it and might observe the wrong value.
1430  *
1431  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
1432  * core changes this before calling sched_move_task().
1433  *
1434  * Instead we use a 'copy' which is updated from sched_move_task() while
1435  * holding both task_struct::pi_lock and rq::lock.
1436  */
1437 static inline struct task_group *task_group(struct task_struct *p)
1438 {
1439 	return p->sched_task_group;
1440 }
1441 
1442 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
1443 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
1444 {
1445 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
1446 	struct task_group *tg = task_group(p);
1447 #endif
1448 
1449 #ifdef CONFIG_FAIR_GROUP_SCHED
1450 	set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
1451 	p->se.cfs_rq = tg->cfs_rq[cpu];
1452 	p->se.parent = tg->se[cpu];
1453 #endif
1454 
1455 #ifdef CONFIG_RT_GROUP_SCHED
1456 	p->rt.rt_rq  = tg->rt_rq[cpu];
1457 	p->rt.parent = tg->rt_se[cpu];
1458 #endif
1459 }
1460 
1461 #else /* CONFIG_CGROUP_SCHED */
1462 
1463 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
1464 static inline struct task_group *task_group(struct task_struct *p)
1465 {
1466 	return NULL;
1467 }
1468 
1469 #endif /* CONFIG_CGROUP_SCHED */
1470 
1471 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
1472 {
1473 	set_task_rq(p, cpu);
1474 #ifdef CONFIG_SMP
1475 	/*
1476 	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
1477 	 * successfully executed on another CPU. We must ensure that updates of
1478 	 * per-task data have been completed by this moment.
1479 	 */
1480 	smp_wmb();
1481 #ifdef CONFIG_THREAD_INFO_IN_TASK
1482 	WRITE_ONCE(p->cpu, cpu);
1483 #else
1484 	WRITE_ONCE(task_thread_info(p)->cpu, cpu);
1485 #endif
1486 	p->wake_cpu = cpu;
1487 #endif
1488 }
1489 
1490 /*
1491  * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
1492  */
1493 #ifdef CONFIG_SCHED_DEBUG
1494 # include <linux/static_key.h>
1495 # define const_debug __read_mostly
1496 #else
1497 # define const_debug const
1498 #endif
1499 
1500 #define SCHED_FEAT(name, enabled)	\
1501 	__SCHED_FEAT_##name ,
1502 
1503 enum {
1504 #include "features.h"
1505 	__SCHED_FEAT_NR,
1506 };
1507 
1508 #undef SCHED_FEAT
1509 
1510 #if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_JUMP_LABEL)
1511 
1512 /*
1513  * To support run-time toggling of sched features, all the translation units
1514  * (but core.c) reference the sysctl_sched_features defined in core.c.
1515  */
1516 extern const_debug unsigned int sysctl_sched_features;
1517 
1518 #define SCHED_FEAT(name, enabled)					\
1519 static __always_inline bool static_branch_##name(struct static_key *key) \
1520 {									\
1521 	return static_key_##enabled(key);				\
1522 }
1523 
1524 #include "features.h"
1525 #undef SCHED_FEAT
1526 
1527 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
1528 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
1529 
1530 #else /* !(SCHED_DEBUG && CONFIG_JUMP_LABEL) */
1531 
1532 /*
1533  * Each translation unit has its own copy of sysctl_sched_features to allow
1534  * constants propagation at compile time and compiler optimization based on
1535  * features default.
1536  */
1537 #define SCHED_FEAT(name, enabled)	\
1538 	(1UL << __SCHED_FEAT_##name) * enabled |
1539 static const_debug __maybe_unused unsigned int sysctl_sched_features =
1540 #include "features.h"
1541 	0;
1542 #undef SCHED_FEAT
1543 
1544 #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1545 
1546 #endif /* SCHED_DEBUG && CONFIG_JUMP_LABEL */
1547 
1548 extern struct static_key_false sched_numa_balancing;
1549 extern struct static_key_false sched_schedstats;
1550 
1551 static inline u64 global_rt_period(void)
1552 {
1553 	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
1554 }
1555 
1556 static inline u64 global_rt_runtime(void)
1557 {
1558 	if (sysctl_sched_rt_runtime < 0)
1559 		return RUNTIME_INF;
1560 
1561 	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
1562 }
1563 
1564 static inline int task_current(struct rq *rq, struct task_struct *p)
1565 {
1566 	return rq->curr == p;
1567 }
1568 
1569 static inline int task_running(struct rq *rq, struct task_struct *p)
1570 {
1571 #ifdef CONFIG_SMP
1572 	return p->on_cpu;
1573 #else
1574 	return task_current(rq, p);
1575 #endif
1576 }
1577 
1578 static inline int task_on_rq_queued(struct task_struct *p)
1579 {
1580 	return p->on_rq == TASK_ON_RQ_QUEUED;
1581 }
1582 
1583 static inline int task_on_rq_migrating(struct task_struct *p)
1584 {
1585 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
1586 }
1587 
1588 /*
1589  * wake flags
1590  */
1591 #define WF_SYNC			0x01		/* Waker goes to sleep after wakeup */
1592 #define WF_FORK			0x02		/* Child wakeup after fork */
1593 #define WF_MIGRATED		0x4		/* Internal use, task got migrated */
1594 
1595 /*
1596  * To aid in avoiding the subversion of "niceness" due to uneven distribution
1597  * of tasks with abnormal "nice" values across CPUs the contribution that
1598  * each task makes to its run queue's load is weighted according to its
1599  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
1600  * scaled version of the new time slice allocation that they receive on time
1601  * slice expiry etc.
1602  */
1603 
1604 #define WEIGHT_IDLEPRIO		3
1605 #define WMULT_IDLEPRIO		1431655765
1606 
1607 extern const int		sched_prio_to_weight[40];
1608 extern const u32		sched_prio_to_wmult[40];
1609 
1610 /*
1611  * {de,en}queue flags:
1612  *
1613  * DEQUEUE_SLEEP  - task is no longer runnable
1614  * ENQUEUE_WAKEUP - task just became runnable
1615  *
1616  * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
1617  *                are in a known state which allows modification. Such pairs
1618  *                should preserve as much state as possible.
1619  *
1620  * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
1621  *        in the runqueue.
1622  *
1623  * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
1624  * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
1625  * ENQUEUE_MIGRATED  - the task was migrated during wakeup
1626  *
1627  */
1628 
1629 #define DEQUEUE_SLEEP		0x01
1630 #define DEQUEUE_SAVE		0x02 /* Matches ENQUEUE_RESTORE */
1631 #define DEQUEUE_MOVE		0x04 /* Matches ENQUEUE_MOVE */
1632 #define DEQUEUE_NOCLOCK		0x08 /* Matches ENQUEUE_NOCLOCK */
1633 
1634 #define ENQUEUE_WAKEUP		0x01
1635 #define ENQUEUE_RESTORE		0x02
1636 #define ENQUEUE_MOVE		0x04
1637 #define ENQUEUE_NOCLOCK		0x08
1638 
1639 #define ENQUEUE_HEAD		0x10
1640 #define ENQUEUE_REPLENISH	0x20
1641 #ifdef CONFIG_SMP
1642 #define ENQUEUE_MIGRATED	0x40
1643 #else
1644 #define ENQUEUE_MIGRATED	0x00
1645 #endif
1646 
1647 #define RETRY_TASK		((void *)-1UL)
1648 
1649 struct sched_class {
1650 	const struct sched_class *next;
1651 
1652 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1653 	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1654 	void (*yield_task)   (struct rq *rq);
1655 	bool (*yield_to_task)(struct rq *rq, struct task_struct *p, bool preempt);
1656 
1657 	void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags);
1658 
1659 	/*
1660 	 * It is the responsibility of the pick_next_task() method that will
1661 	 * return the next task to call put_prev_task() on the @prev task or
1662 	 * something equivalent.
1663 	 *
1664 	 * May return RETRY_TASK when it finds a higher prio class has runnable
1665 	 * tasks.
1666 	 */
1667 	struct task_struct * (*pick_next_task)(struct rq *rq,
1668 					       struct task_struct *prev,
1669 					       struct rq_flags *rf);
1670 	void (*put_prev_task)(struct rq *rq, struct task_struct *p);
1671 
1672 #ifdef CONFIG_SMP
1673 	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
1674 	void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
1675 
1676 	void (*task_woken)(struct rq *this_rq, struct task_struct *task);
1677 
1678 	void (*set_cpus_allowed)(struct task_struct *p,
1679 				 const struct cpumask *newmask);
1680 
1681 	void (*rq_online)(struct rq *rq);
1682 	void (*rq_offline)(struct rq *rq);
1683 #endif
1684 
1685 	void (*set_curr_task)(struct rq *rq);
1686 	void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
1687 	void (*task_fork)(struct task_struct *p);
1688 	void (*task_dead)(struct task_struct *p);
1689 
1690 	/*
1691 	 * The switched_from() call is allowed to drop rq->lock, therefore we
1692 	 * cannot assume the switched_from/switched_to pair is serliazed by
1693 	 * rq->lock. They are however serialized by p->pi_lock.
1694 	 */
1695 	void (*switched_from)(struct rq *this_rq, struct task_struct *task);
1696 	void (*switched_to)  (struct rq *this_rq, struct task_struct *task);
1697 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1698 			      int oldprio);
1699 
1700 	unsigned int (*get_rr_interval)(struct rq *rq,
1701 					struct task_struct *task);
1702 
1703 	void (*update_curr)(struct rq *rq);
1704 
1705 #define TASK_SET_GROUP		0
1706 #define TASK_MOVE_GROUP		1
1707 
1708 #ifdef CONFIG_FAIR_GROUP_SCHED
1709 	void (*task_change_group)(struct task_struct *p, int type);
1710 #endif
1711 };
1712 
1713 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
1714 {
1715 	prev->sched_class->put_prev_task(rq, prev);
1716 }
1717 
1718 static inline void set_curr_task(struct rq *rq, struct task_struct *curr)
1719 {
1720 	curr->sched_class->set_curr_task(rq);
1721 }
1722 
1723 #ifdef CONFIG_SMP
1724 #define sched_class_highest (&stop_sched_class)
1725 #else
1726 #define sched_class_highest (&dl_sched_class)
1727 #endif
1728 #define for_each_class(class) \
1729    for (class = sched_class_highest; class; class = class->next)
1730 
1731 extern const struct sched_class stop_sched_class;
1732 extern const struct sched_class dl_sched_class;
1733 extern const struct sched_class rt_sched_class;
1734 extern const struct sched_class fair_sched_class;
1735 extern const struct sched_class idle_sched_class;
1736 
1737 
1738 #ifdef CONFIG_SMP
1739 
1740 extern void update_group_capacity(struct sched_domain *sd, int cpu);
1741 
1742 extern void trigger_load_balance(struct rq *rq);
1743 
1744 extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask);
1745 
1746 #endif
1747 
1748 #ifdef CONFIG_CPU_IDLE
1749 static inline void idle_set_state(struct rq *rq,
1750 				  struct cpuidle_state *idle_state)
1751 {
1752 	rq->idle_state = idle_state;
1753 }
1754 
1755 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1756 {
1757 	SCHED_WARN_ON(!rcu_read_lock_held());
1758 
1759 	return rq->idle_state;
1760 }
1761 #else
1762 static inline void idle_set_state(struct rq *rq,
1763 				  struct cpuidle_state *idle_state)
1764 {
1765 }
1766 
1767 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1768 {
1769 	return NULL;
1770 }
1771 #endif
1772 
1773 extern void schedule_idle(void);
1774 
1775 extern void sysrq_sched_debug_show(void);
1776 extern void sched_init_granularity(void);
1777 extern void update_max_interval(void);
1778 
1779 extern void init_sched_dl_class(void);
1780 extern void init_sched_rt_class(void);
1781 extern void init_sched_fair_class(void);
1782 
1783 extern void reweight_task(struct task_struct *p, int prio);
1784 
1785 extern void resched_curr(struct rq *rq);
1786 extern void resched_cpu(int cpu);
1787 
1788 extern struct rt_bandwidth def_rt_bandwidth;
1789 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
1790 
1791 extern struct dl_bandwidth def_dl_bandwidth;
1792 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
1793 extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
1794 extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se);
1795 extern void init_dl_rq_bw_ratio(struct dl_rq *dl_rq);
1796 
1797 #define BW_SHIFT		20
1798 #define BW_UNIT			(1 << BW_SHIFT)
1799 #define RATIO_SHIFT		8
1800 unsigned long to_ratio(u64 period, u64 runtime);
1801 
1802 extern void init_entity_runnable_average(struct sched_entity *se);
1803 extern void post_init_entity_util_avg(struct task_struct *p);
1804 
1805 #ifdef CONFIG_NO_HZ_FULL
1806 extern bool sched_can_stop_tick(struct rq *rq);
1807 extern int __init sched_tick_offload_init(void);
1808 
1809 /*
1810  * Tick may be needed by tasks in the runqueue depending on their policy and
1811  * requirements. If tick is needed, lets send the target an IPI to kick it out of
1812  * nohz mode if necessary.
1813  */
1814 static inline void sched_update_tick_dependency(struct rq *rq)
1815 {
1816 	int cpu;
1817 
1818 	if (!tick_nohz_full_enabled())
1819 		return;
1820 
1821 	cpu = cpu_of(rq);
1822 
1823 	if (!tick_nohz_full_cpu(cpu))
1824 		return;
1825 
1826 	if (sched_can_stop_tick(rq))
1827 		tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
1828 	else
1829 		tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
1830 }
1831 #else
1832 static inline int sched_tick_offload_init(void) { return 0; }
1833 static inline void sched_update_tick_dependency(struct rq *rq) { }
1834 #endif
1835 
1836 static inline void add_nr_running(struct rq *rq, unsigned count)
1837 {
1838 	unsigned prev_nr = rq->nr_running;
1839 
1840 	rq->nr_running = prev_nr + count;
1841 
1842 #ifdef CONFIG_SMP
1843 	if (prev_nr < 2 && rq->nr_running >= 2) {
1844 		if (!READ_ONCE(rq->rd->overload))
1845 			WRITE_ONCE(rq->rd->overload, 1);
1846 	}
1847 #endif
1848 
1849 	sched_update_tick_dependency(rq);
1850 }
1851 
1852 static inline void sub_nr_running(struct rq *rq, unsigned count)
1853 {
1854 	rq->nr_running -= count;
1855 	/* Check if we still need preemption */
1856 	sched_update_tick_dependency(rq);
1857 }
1858 
1859 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
1860 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
1861 
1862 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
1863 
1864 extern const_debug unsigned int sysctl_sched_nr_migrate;
1865 extern const_debug unsigned int sysctl_sched_migration_cost;
1866 
1867 #ifdef CONFIG_SCHED_HRTICK
1868 
1869 /*
1870  * Use hrtick when:
1871  *  - enabled by features
1872  *  - hrtimer is actually high res
1873  */
1874 static inline int hrtick_enabled(struct rq *rq)
1875 {
1876 	if (!sched_feat(HRTICK))
1877 		return 0;
1878 	if (!cpu_active(cpu_of(rq)))
1879 		return 0;
1880 	return hrtimer_is_hres_active(&rq->hrtick_timer);
1881 }
1882 
1883 void hrtick_start(struct rq *rq, u64 delay);
1884 
1885 #else
1886 
1887 static inline int hrtick_enabled(struct rq *rq)
1888 {
1889 	return 0;
1890 }
1891 
1892 #endif /* CONFIG_SCHED_HRTICK */
1893 
1894 #ifndef arch_scale_freq_capacity
1895 static __always_inline
1896 unsigned long arch_scale_freq_capacity(int cpu)
1897 {
1898 	return SCHED_CAPACITY_SCALE;
1899 }
1900 #endif
1901 
1902 #ifdef CONFIG_SMP
1903 #ifdef CONFIG_PREEMPT
1904 
1905 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2);
1906 
1907 /*
1908  * fair double_lock_balance: Safely acquires both rq->locks in a fair
1909  * way at the expense of forcing extra atomic operations in all
1910  * invocations.  This assures that the double_lock is acquired using the
1911  * same underlying policy as the spinlock_t on this architecture, which
1912  * reduces latency compared to the unfair variant below.  However, it
1913  * also adds more overhead and therefore may reduce throughput.
1914  */
1915 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1916 	__releases(this_rq->lock)
1917 	__acquires(busiest->lock)
1918 	__acquires(this_rq->lock)
1919 {
1920 	raw_spin_unlock(&this_rq->lock);
1921 	double_rq_lock(this_rq, busiest);
1922 
1923 	return 1;
1924 }
1925 
1926 #else
1927 /*
1928  * Unfair double_lock_balance: Optimizes throughput at the expense of
1929  * latency by eliminating extra atomic operations when the locks are
1930  * already in proper order on entry.  This favors lower CPU-ids and will
1931  * grant the double lock to lower CPUs over higher ids under contention,
1932  * regardless of entry order into the function.
1933  */
1934 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1935 	__releases(this_rq->lock)
1936 	__acquires(busiest->lock)
1937 	__acquires(this_rq->lock)
1938 {
1939 	int ret = 0;
1940 
1941 	if (unlikely(!raw_spin_trylock(&busiest->lock))) {
1942 		if (busiest < this_rq) {
1943 			raw_spin_unlock(&this_rq->lock);
1944 			raw_spin_lock(&busiest->lock);
1945 			raw_spin_lock_nested(&this_rq->lock,
1946 					      SINGLE_DEPTH_NESTING);
1947 			ret = 1;
1948 		} else
1949 			raw_spin_lock_nested(&busiest->lock,
1950 					      SINGLE_DEPTH_NESTING);
1951 	}
1952 	return ret;
1953 }
1954 
1955 #endif /* CONFIG_PREEMPT */
1956 
1957 /*
1958  * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
1959  */
1960 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
1961 {
1962 	if (unlikely(!irqs_disabled())) {
1963 		/* printk() doesn't work well under rq->lock */
1964 		raw_spin_unlock(&this_rq->lock);
1965 		BUG_ON(1);
1966 	}
1967 
1968 	return _double_lock_balance(this_rq, busiest);
1969 }
1970 
1971 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
1972 	__releases(busiest->lock)
1973 {
1974 	raw_spin_unlock(&busiest->lock);
1975 	lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
1976 }
1977 
1978 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
1979 {
1980 	if (l1 > l2)
1981 		swap(l1, l2);
1982 
1983 	spin_lock(l1);
1984 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1985 }
1986 
1987 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
1988 {
1989 	if (l1 > l2)
1990 		swap(l1, l2);
1991 
1992 	spin_lock_irq(l1);
1993 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1994 }
1995 
1996 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
1997 {
1998 	if (l1 > l2)
1999 		swap(l1, l2);
2000 
2001 	raw_spin_lock(l1);
2002 	raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2003 }
2004 
2005 /*
2006  * double_rq_lock - safely lock two runqueues
2007  *
2008  * Note this does not disable interrupts like task_rq_lock,
2009  * you need to do so manually before calling.
2010  */
2011 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2012 	__acquires(rq1->lock)
2013 	__acquires(rq2->lock)
2014 {
2015 	BUG_ON(!irqs_disabled());
2016 	if (rq1 == rq2) {
2017 		raw_spin_lock(&rq1->lock);
2018 		__acquire(rq2->lock);	/* Fake it out ;) */
2019 	} else {
2020 		if (rq1 < rq2) {
2021 			raw_spin_lock(&rq1->lock);
2022 			raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
2023 		} else {
2024 			raw_spin_lock(&rq2->lock);
2025 			raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
2026 		}
2027 	}
2028 }
2029 
2030 /*
2031  * double_rq_unlock - safely unlock two runqueues
2032  *
2033  * Note this does not restore interrupts like task_rq_unlock,
2034  * you need to do so manually after calling.
2035  */
2036 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2037 	__releases(rq1->lock)
2038 	__releases(rq2->lock)
2039 {
2040 	raw_spin_unlock(&rq1->lock);
2041 	if (rq1 != rq2)
2042 		raw_spin_unlock(&rq2->lock);
2043 	else
2044 		__release(rq2->lock);
2045 }
2046 
2047 extern void set_rq_online (struct rq *rq);
2048 extern void set_rq_offline(struct rq *rq);
2049 extern bool sched_smp_initialized;
2050 
2051 #else /* CONFIG_SMP */
2052 
2053 /*
2054  * double_rq_lock - safely lock two runqueues
2055  *
2056  * Note this does not disable interrupts like task_rq_lock,
2057  * you need to do so manually before calling.
2058  */
2059 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2060 	__acquires(rq1->lock)
2061 	__acquires(rq2->lock)
2062 {
2063 	BUG_ON(!irqs_disabled());
2064 	BUG_ON(rq1 != rq2);
2065 	raw_spin_lock(&rq1->lock);
2066 	__acquire(rq2->lock);	/* Fake it out ;) */
2067 }
2068 
2069 /*
2070  * double_rq_unlock - safely unlock two runqueues
2071  *
2072  * Note this does not restore interrupts like task_rq_unlock,
2073  * you need to do so manually after calling.
2074  */
2075 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2076 	__releases(rq1->lock)
2077 	__releases(rq2->lock)
2078 {
2079 	BUG_ON(rq1 != rq2);
2080 	raw_spin_unlock(&rq1->lock);
2081 	__release(rq2->lock);
2082 }
2083 
2084 #endif
2085 
2086 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
2087 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
2088 
2089 #ifdef	CONFIG_SCHED_DEBUG
2090 extern bool sched_debug_enabled;
2091 
2092 extern void print_cfs_stats(struct seq_file *m, int cpu);
2093 extern void print_rt_stats(struct seq_file *m, int cpu);
2094 extern void print_dl_stats(struct seq_file *m, int cpu);
2095 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
2096 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
2097 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
2098 #ifdef CONFIG_NUMA_BALANCING
2099 extern void
2100 show_numa_stats(struct task_struct *p, struct seq_file *m);
2101 extern void
2102 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
2103 	unsigned long tpf, unsigned long gsf, unsigned long gpf);
2104 #endif /* CONFIG_NUMA_BALANCING */
2105 #endif /* CONFIG_SCHED_DEBUG */
2106 
2107 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
2108 extern void init_rt_rq(struct rt_rq *rt_rq);
2109 extern void init_dl_rq(struct dl_rq *dl_rq);
2110 
2111 extern void cfs_bandwidth_usage_inc(void);
2112 extern void cfs_bandwidth_usage_dec(void);
2113 
2114 #ifdef CONFIG_NO_HZ_COMMON
2115 #define NOHZ_BALANCE_KICK_BIT	0
2116 #define NOHZ_STATS_KICK_BIT	1
2117 
2118 #define NOHZ_BALANCE_KICK	BIT(NOHZ_BALANCE_KICK_BIT)
2119 #define NOHZ_STATS_KICK		BIT(NOHZ_STATS_KICK_BIT)
2120 
2121 #define NOHZ_KICK_MASK	(NOHZ_BALANCE_KICK | NOHZ_STATS_KICK)
2122 
2123 #define nohz_flags(cpu)	(&cpu_rq(cpu)->nohz_flags)
2124 
2125 extern void nohz_balance_exit_idle(struct rq *rq);
2126 #else
2127 static inline void nohz_balance_exit_idle(struct rq *rq) { }
2128 #endif
2129 
2130 
2131 #ifdef CONFIG_SMP
2132 static inline
2133 void __dl_update(struct dl_bw *dl_b, s64 bw)
2134 {
2135 	struct root_domain *rd = container_of(dl_b, struct root_domain, dl_bw);
2136 	int i;
2137 
2138 	RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
2139 			 "sched RCU must be held");
2140 	for_each_cpu_and(i, rd->span, cpu_active_mask) {
2141 		struct rq *rq = cpu_rq(i);
2142 
2143 		rq->dl.extra_bw += bw;
2144 	}
2145 }
2146 #else
2147 static inline
2148 void __dl_update(struct dl_bw *dl_b, s64 bw)
2149 {
2150 	struct dl_rq *dl = container_of(dl_b, struct dl_rq, dl_bw);
2151 
2152 	dl->extra_bw += bw;
2153 }
2154 #endif
2155 
2156 
2157 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2158 struct irqtime {
2159 	u64			total;
2160 	u64			tick_delta;
2161 	u64			irq_start_time;
2162 	struct u64_stats_sync	sync;
2163 };
2164 
2165 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
2166 
2167 /*
2168  * Returns the irqtime minus the softirq time computed by ksoftirqd.
2169  * Otherwise ksoftirqd's sum_exec_runtime is substracted its own runtime
2170  * and never move forward.
2171  */
2172 static inline u64 irq_time_read(int cpu)
2173 {
2174 	struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
2175 	unsigned int seq;
2176 	u64 total;
2177 
2178 	do {
2179 		seq = __u64_stats_fetch_begin(&irqtime->sync);
2180 		total = irqtime->total;
2181 	} while (__u64_stats_fetch_retry(&irqtime->sync, seq));
2182 
2183 	return total;
2184 }
2185 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
2186 
2187 #ifdef CONFIG_CPU_FREQ
2188 DECLARE_PER_CPU(struct update_util_data *, cpufreq_update_util_data);
2189 
2190 /**
2191  * cpufreq_update_util - Take a note about CPU utilization changes.
2192  * @rq: Runqueue to carry out the update for.
2193  * @flags: Update reason flags.
2194  *
2195  * This function is called by the scheduler on the CPU whose utilization is
2196  * being updated.
2197  *
2198  * It can only be called from RCU-sched read-side critical sections.
2199  *
2200  * The way cpufreq is currently arranged requires it to evaluate the CPU
2201  * performance state (frequency/voltage) on a regular basis to prevent it from
2202  * being stuck in a completely inadequate performance level for too long.
2203  * That is not guaranteed to happen if the updates are only triggered from CFS
2204  * and DL, though, because they may not be coming in if only RT tasks are
2205  * active all the time (or there are RT tasks only).
2206  *
2207  * As a workaround for that issue, this function is called periodically by the
2208  * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
2209  * but that really is a band-aid.  Going forward it should be replaced with
2210  * solutions targeted more specifically at RT tasks.
2211  */
2212 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
2213 {
2214 	struct update_util_data *data;
2215 
2216 	data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
2217 						  cpu_of(rq)));
2218 	if (data)
2219 		data->func(data, rq_clock(rq), flags);
2220 }
2221 #else
2222 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
2223 #endif /* CONFIG_CPU_FREQ */
2224 
2225 #ifdef arch_scale_freq_capacity
2226 # ifndef arch_scale_freq_invariant
2227 #  define arch_scale_freq_invariant()	true
2228 # endif
2229 #else
2230 # define arch_scale_freq_invariant()	false
2231 #endif
2232 
2233 #ifdef CONFIG_SMP
2234 static inline unsigned long capacity_orig_of(int cpu)
2235 {
2236 	return cpu_rq(cpu)->cpu_capacity_orig;
2237 }
2238 #endif
2239 
2240 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
2241 /**
2242  * enum schedutil_type - CPU utilization type
2243  * @FREQUENCY_UTIL:	Utilization used to select frequency
2244  * @ENERGY_UTIL:	Utilization used during energy calculation
2245  *
2246  * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time
2247  * need to be aggregated differently depending on the usage made of them. This
2248  * enum is used within schedutil_freq_util() to differentiate the types of
2249  * utilization expected by the callers, and adjust the aggregation accordingly.
2250  */
2251 enum schedutil_type {
2252 	FREQUENCY_UTIL,
2253 	ENERGY_UTIL,
2254 };
2255 
2256 unsigned long schedutil_freq_util(int cpu, unsigned long util_cfs,
2257 				  unsigned long max, enum schedutil_type type);
2258 
2259 static inline unsigned long schedutil_energy_util(int cpu, unsigned long cfs)
2260 {
2261 	unsigned long max = arch_scale_cpu_capacity(NULL, cpu);
2262 
2263 	return schedutil_freq_util(cpu, cfs, max, ENERGY_UTIL);
2264 }
2265 
2266 static inline unsigned long cpu_bw_dl(struct rq *rq)
2267 {
2268 	return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
2269 }
2270 
2271 static inline unsigned long cpu_util_dl(struct rq *rq)
2272 {
2273 	return READ_ONCE(rq->avg_dl.util_avg);
2274 }
2275 
2276 static inline unsigned long cpu_util_cfs(struct rq *rq)
2277 {
2278 	unsigned long util = READ_ONCE(rq->cfs.avg.util_avg);
2279 
2280 	if (sched_feat(UTIL_EST)) {
2281 		util = max_t(unsigned long, util,
2282 			     READ_ONCE(rq->cfs.avg.util_est.enqueued));
2283 	}
2284 
2285 	return util;
2286 }
2287 
2288 static inline unsigned long cpu_util_rt(struct rq *rq)
2289 {
2290 	return READ_ONCE(rq->avg_rt.util_avg);
2291 }
2292 #else /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
2293 static inline unsigned long schedutil_energy_util(int cpu, unsigned long cfs)
2294 {
2295 	return cfs;
2296 }
2297 #endif
2298 
2299 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
2300 static inline unsigned long cpu_util_irq(struct rq *rq)
2301 {
2302 	return rq->avg_irq.util_avg;
2303 }
2304 
2305 static inline
2306 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2307 {
2308 	util *= (max - irq);
2309 	util /= max;
2310 
2311 	return util;
2312 
2313 }
2314 #else
2315 static inline unsigned long cpu_util_irq(struct rq *rq)
2316 {
2317 	return 0;
2318 }
2319 
2320 static inline
2321 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2322 {
2323 	return util;
2324 }
2325 #endif
2326 
2327 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
2328 
2329 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
2330 
2331 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
2332 
2333 static inline bool sched_energy_enabled(void)
2334 {
2335 	return static_branch_unlikely(&sched_energy_present);
2336 }
2337 
2338 #else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
2339 
2340 #define perf_domain_span(pd) NULL
2341 static inline bool sched_energy_enabled(void) { return false; }
2342 
2343 #endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
2344