xref: /openbmc/linux/kernel/sched/sched.h (revision 8e9356c6)
1 
2 #include <linux/sched.h>
3 #include <linux/sched/sysctl.h>
4 #include <linux/sched/rt.h>
5 #include <linux/sched/deadline.h>
6 #include <linux/mutex.h>
7 #include <linux/spinlock.h>
8 #include <linux/stop_machine.h>
9 #include <linux/tick.h>
10 #include <linux/slab.h>
11 
12 #include "cpupri.h"
13 #include "cpudeadline.h"
14 #include "cpuacct.h"
15 
16 struct rq;
17 
18 extern __read_mostly int scheduler_running;
19 
20 extern unsigned long calc_load_update;
21 extern atomic_long_t calc_load_tasks;
22 
23 extern long calc_load_fold_active(struct rq *this_rq);
24 extern void update_cpu_load_active(struct rq *this_rq);
25 
26 /*
27  * Convert user-nice values [ -20 ... 0 ... 19 ]
28  * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
29  * and back.
30  */
31 #define NICE_TO_PRIO(nice)	(MAX_RT_PRIO + (nice) + 20)
32 #define PRIO_TO_NICE(prio)	((prio) - MAX_RT_PRIO - 20)
33 #define TASK_NICE(p)		PRIO_TO_NICE((p)->static_prio)
34 
35 /*
36  * 'User priority' is the nice value converted to something we
37  * can work with better when scaling various scheduler parameters,
38  * it's a [ 0 ... 39 ] range.
39  */
40 #define USER_PRIO(p)		((p)-MAX_RT_PRIO)
41 #define TASK_USER_PRIO(p)	USER_PRIO((p)->static_prio)
42 #define MAX_USER_PRIO		(USER_PRIO(MAX_PRIO))
43 
44 /*
45  * Helpers for converting nanosecond timing to jiffy resolution
46  */
47 #define NS_TO_JIFFIES(TIME)	((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
48 
49 /*
50  * Increase resolution of nice-level calculations for 64-bit architectures.
51  * The extra resolution improves shares distribution and load balancing of
52  * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
53  * hierarchies, especially on larger systems. This is not a user-visible change
54  * and does not change the user-interface for setting shares/weights.
55  *
56  * We increase resolution only if we have enough bits to allow this increased
57  * resolution (i.e. BITS_PER_LONG > 32). The costs for increasing resolution
58  * when BITS_PER_LONG <= 32 are pretty high and the returns do not justify the
59  * increased costs.
60  */
61 #if 0 /* BITS_PER_LONG > 32 -- currently broken: it increases power usage under light load  */
62 # define SCHED_LOAD_RESOLUTION	10
63 # define scale_load(w)		((w) << SCHED_LOAD_RESOLUTION)
64 # define scale_load_down(w)	((w) >> SCHED_LOAD_RESOLUTION)
65 #else
66 # define SCHED_LOAD_RESOLUTION	0
67 # define scale_load(w)		(w)
68 # define scale_load_down(w)	(w)
69 #endif
70 
71 #define SCHED_LOAD_SHIFT	(10 + SCHED_LOAD_RESOLUTION)
72 #define SCHED_LOAD_SCALE	(1L << SCHED_LOAD_SHIFT)
73 
74 #define NICE_0_LOAD		SCHED_LOAD_SCALE
75 #define NICE_0_SHIFT		SCHED_LOAD_SHIFT
76 
77 /*
78  * Single value that decides SCHED_DEADLINE internal math precision.
79  * 10 -> just above 1us
80  * 9  -> just above 0.5us
81  */
82 #define DL_SCALE (10)
83 
84 /*
85  * These are the 'tuning knobs' of the scheduler:
86  */
87 
88 /*
89  * single value that denotes runtime == period, ie unlimited time.
90  */
91 #define RUNTIME_INF	((u64)~0ULL)
92 
93 static inline int fair_policy(int policy)
94 {
95 	return policy == SCHED_NORMAL || policy == SCHED_BATCH;
96 }
97 
98 static inline int rt_policy(int policy)
99 {
100 	return policy == SCHED_FIFO || policy == SCHED_RR;
101 }
102 
103 static inline int dl_policy(int policy)
104 {
105 	return policy == SCHED_DEADLINE;
106 }
107 
108 static inline int task_has_rt_policy(struct task_struct *p)
109 {
110 	return rt_policy(p->policy);
111 }
112 
113 static inline int task_has_dl_policy(struct task_struct *p)
114 {
115 	return dl_policy(p->policy);
116 }
117 
118 static inline bool dl_time_before(u64 a, u64 b)
119 {
120 	return (s64)(a - b) < 0;
121 }
122 
123 /*
124  * Tells if entity @a should preempt entity @b.
125  */
126 static inline bool
127 dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
128 {
129 	return dl_time_before(a->deadline, b->deadline);
130 }
131 
132 /*
133  * This is the priority-queue data structure of the RT scheduling class:
134  */
135 struct rt_prio_array {
136 	DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
137 	struct list_head queue[MAX_RT_PRIO];
138 };
139 
140 struct rt_bandwidth {
141 	/* nests inside the rq lock: */
142 	raw_spinlock_t		rt_runtime_lock;
143 	ktime_t			rt_period;
144 	u64			rt_runtime;
145 	struct hrtimer		rt_period_timer;
146 };
147 /*
148  * To keep the bandwidth of -deadline tasks and groups under control
149  * we need some place where:
150  *  - store the maximum -deadline bandwidth of the system (the group);
151  *  - cache the fraction of that bandwidth that is currently allocated.
152  *
153  * This is all done in the data structure below. It is similar to the
154  * one used for RT-throttling (rt_bandwidth), with the main difference
155  * that, since here we are only interested in admission control, we
156  * do not decrease any runtime while the group "executes", neither we
157  * need a timer to replenish it.
158  *
159  * With respect to SMP, the bandwidth is given on a per-CPU basis,
160  * meaning that:
161  *  - dl_bw (< 100%) is the bandwidth of the system (group) on each CPU;
162  *  - dl_total_bw array contains, in the i-eth element, the currently
163  *    allocated bandwidth on the i-eth CPU.
164  * Moreover, groups consume bandwidth on each CPU, while tasks only
165  * consume bandwidth on the CPU they're running on.
166  * Finally, dl_total_bw_cpu is used to cache the index of dl_total_bw
167  * that will be shown the next time the proc or cgroup controls will
168  * be red. It on its turn can be changed by writing on its own
169  * control.
170  */
171 struct dl_bandwidth {
172 	raw_spinlock_t dl_runtime_lock;
173 	u64 dl_runtime;
174 	u64 dl_period;
175 };
176 
177 static inline int dl_bandwidth_enabled(void)
178 {
179 	return sysctl_sched_rt_runtime >= 0;
180 }
181 
182 extern struct dl_bw *dl_bw_of(int i);
183 
184 struct dl_bw {
185 	raw_spinlock_t lock;
186 	u64 bw, total_bw;
187 };
188 
189 extern struct mutex sched_domains_mutex;
190 
191 #ifdef CONFIG_CGROUP_SCHED
192 
193 #include <linux/cgroup.h>
194 
195 struct cfs_rq;
196 struct rt_rq;
197 
198 extern struct list_head task_groups;
199 
200 struct cfs_bandwidth {
201 #ifdef CONFIG_CFS_BANDWIDTH
202 	raw_spinlock_t lock;
203 	ktime_t period;
204 	u64 quota, runtime;
205 	s64 hierarchal_quota;
206 	u64 runtime_expires;
207 
208 	int idle, timer_active;
209 	struct hrtimer period_timer, slack_timer;
210 	struct list_head throttled_cfs_rq;
211 
212 	/* statistics */
213 	int nr_periods, nr_throttled;
214 	u64 throttled_time;
215 #endif
216 };
217 
218 /* task group related information */
219 struct task_group {
220 	struct cgroup_subsys_state css;
221 
222 #ifdef CONFIG_FAIR_GROUP_SCHED
223 	/* schedulable entities of this group on each cpu */
224 	struct sched_entity **se;
225 	/* runqueue "owned" by this group on each cpu */
226 	struct cfs_rq **cfs_rq;
227 	unsigned long shares;
228 
229 #ifdef	CONFIG_SMP
230 	atomic_long_t load_avg;
231 	atomic_t runnable_avg;
232 #endif
233 #endif
234 
235 #ifdef CONFIG_RT_GROUP_SCHED
236 	struct sched_rt_entity **rt_se;
237 	struct rt_rq **rt_rq;
238 
239 	struct rt_bandwidth rt_bandwidth;
240 #endif
241 
242 	struct rcu_head rcu;
243 	struct list_head list;
244 
245 	struct task_group *parent;
246 	struct list_head siblings;
247 	struct list_head children;
248 
249 #ifdef CONFIG_SCHED_AUTOGROUP
250 	struct autogroup *autogroup;
251 #endif
252 
253 	struct cfs_bandwidth cfs_bandwidth;
254 };
255 
256 #ifdef CONFIG_FAIR_GROUP_SCHED
257 #define ROOT_TASK_GROUP_LOAD	NICE_0_LOAD
258 
259 /*
260  * A weight of 0 or 1 can cause arithmetics problems.
261  * A weight of a cfs_rq is the sum of weights of which entities
262  * are queued on this cfs_rq, so a weight of a entity should not be
263  * too large, so as the shares value of a task group.
264  * (The default weight is 1024 - so there's no practical
265  *  limitation from this.)
266  */
267 #define MIN_SHARES	(1UL <<  1)
268 #define MAX_SHARES	(1UL << 18)
269 #endif
270 
271 typedef int (*tg_visitor)(struct task_group *, void *);
272 
273 extern int walk_tg_tree_from(struct task_group *from,
274 			     tg_visitor down, tg_visitor up, void *data);
275 
276 /*
277  * Iterate the full tree, calling @down when first entering a node and @up when
278  * leaving it for the final time.
279  *
280  * Caller must hold rcu_lock or sufficient equivalent.
281  */
282 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
283 {
284 	return walk_tg_tree_from(&root_task_group, down, up, data);
285 }
286 
287 extern int tg_nop(struct task_group *tg, void *data);
288 
289 extern void free_fair_sched_group(struct task_group *tg);
290 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
291 extern void unregister_fair_sched_group(struct task_group *tg, int cpu);
292 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
293 			struct sched_entity *se, int cpu,
294 			struct sched_entity *parent);
295 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
296 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
297 
298 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
299 extern void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
300 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
301 
302 extern void free_rt_sched_group(struct task_group *tg);
303 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
304 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
305 		struct sched_rt_entity *rt_se, int cpu,
306 		struct sched_rt_entity *parent);
307 
308 extern struct task_group *sched_create_group(struct task_group *parent);
309 extern void sched_online_group(struct task_group *tg,
310 			       struct task_group *parent);
311 extern void sched_destroy_group(struct task_group *tg);
312 extern void sched_offline_group(struct task_group *tg);
313 
314 extern void sched_move_task(struct task_struct *tsk);
315 
316 #ifdef CONFIG_FAIR_GROUP_SCHED
317 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
318 #endif
319 
320 #else /* CONFIG_CGROUP_SCHED */
321 
322 struct cfs_bandwidth { };
323 
324 #endif	/* CONFIG_CGROUP_SCHED */
325 
326 /* CFS-related fields in a runqueue */
327 struct cfs_rq {
328 	struct load_weight load;
329 	unsigned int nr_running, h_nr_running;
330 
331 	u64 exec_clock;
332 	u64 min_vruntime;
333 #ifndef CONFIG_64BIT
334 	u64 min_vruntime_copy;
335 #endif
336 
337 	struct rb_root tasks_timeline;
338 	struct rb_node *rb_leftmost;
339 
340 	/*
341 	 * 'curr' points to currently running entity on this cfs_rq.
342 	 * It is set to NULL otherwise (i.e when none are currently running).
343 	 */
344 	struct sched_entity *curr, *next, *last, *skip;
345 
346 #ifdef	CONFIG_SCHED_DEBUG
347 	unsigned int nr_spread_over;
348 #endif
349 
350 #ifdef CONFIG_SMP
351 	/*
352 	 * CFS Load tracking
353 	 * Under CFS, load is tracked on a per-entity basis and aggregated up.
354 	 * This allows for the description of both thread and group usage (in
355 	 * the FAIR_GROUP_SCHED case).
356 	 */
357 	unsigned long runnable_load_avg, blocked_load_avg;
358 	atomic64_t decay_counter;
359 	u64 last_decay;
360 	atomic_long_t removed_load;
361 
362 #ifdef CONFIG_FAIR_GROUP_SCHED
363 	/* Required to track per-cpu representation of a task_group */
364 	u32 tg_runnable_contrib;
365 	unsigned long tg_load_contrib;
366 
367 	/*
368 	 *   h_load = weight * f(tg)
369 	 *
370 	 * Where f(tg) is the recursive weight fraction assigned to
371 	 * this group.
372 	 */
373 	unsigned long h_load;
374 	u64 last_h_load_update;
375 	struct sched_entity *h_load_next;
376 #endif /* CONFIG_FAIR_GROUP_SCHED */
377 #endif /* CONFIG_SMP */
378 
379 #ifdef CONFIG_FAIR_GROUP_SCHED
380 	struct rq *rq;	/* cpu runqueue to which this cfs_rq is attached */
381 
382 	/*
383 	 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
384 	 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
385 	 * (like users, containers etc.)
386 	 *
387 	 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This
388 	 * list is used during load balance.
389 	 */
390 	int on_list;
391 	struct list_head leaf_cfs_rq_list;
392 	struct task_group *tg;	/* group that "owns" this runqueue */
393 
394 #ifdef CONFIG_CFS_BANDWIDTH
395 	int runtime_enabled;
396 	u64 runtime_expires;
397 	s64 runtime_remaining;
398 
399 	u64 throttled_clock, throttled_clock_task;
400 	u64 throttled_clock_task_time;
401 	int throttled, throttle_count;
402 	struct list_head throttled_list;
403 #endif /* CONFIG_CFS_BANDWIDTH */
404 #endif /* CONFIG_FAIR_GROUP_SCHED */
405 };
406 
407 static inline int rt_bandwidth_enabled(void)
408 {
409 	return sysctl_sched_rt_runtime >= 0;
410 }
411 
412 /* Real-Time classes' related field in a runqueue: */
413 struct rt_rq {
414 	struct rt_prio_array active;
415 	unsigned int rt_nr_running;
416 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
417 	struct {
418 		int curr; /* highest queued rt task prio */
419 #ifdef CONFIG_SMP
420 		int next; /* next highest */
421 #endif
422 	} highest_prio;
423 #endif
424 #ifdef CONFIG_SMP
425 	unsigned long rt_nr_migratory;
426 	unsigned long rt_nr_total;
427 	int overloaded;
428 	struct plist_head pushable_tasks;
429 #endif
430 	int rt_throttled;
431 	u64 rt_time;
432 	u64 rt_runtime;
433 	/* Nests inside the rq lock: */
434 	raw_spinlock_t rt_runtime_lock;
435 
436 #ifdef CONFIG_RT_GROUP_SCHED
437 	unsigned long rt_nr_boosted;
438 
439 	struct rq *rq;
440 	struct task_group *tg;
441 #endif
442 };
443 
444 /* Deadline class' related fields in a runqueue */
445 struct dl_rq {
446 	/* runqueue is an rbtree, ordered by deadline */
447 	struct rb_root rb_root;
448 	struct rb_node *rb_leftmost;
449 
450 	unsigned long dl_nr_running;
451 
452 #ifdef CONFIG_SMP
453 	/*
454 	 * Deadline values of the currently executing and the
455 	 * earliest ready task on this rq. Caching these facilitates
456 	 * the decision wether or not a ready but not running task
457 	 * should migrate somewhere else.
458 	 */
459 	struct {
460 		u64 curr;
461 		u64 next;
462 	} earliest_dl;
463 
464 	unsigned long dl_nr_migratory;
465 	unsigned long dl_nr_total;
466 	int overloaded;
467 
468 	/*
469 	 * Tasks on this rq that can be pushed away. They are kept in
470 	 * an rb-tree, ordered by tasks' deadlines, with caching
471 	 * of the leftmost (earliest deadline) element.
472 	 */
473 	struct rb_root pushable_dl_tasks_root;
474 	struct rb_node *pushable_dl_tasks_leftmost;
475 #else
476 	struct dl_bw dl_bw;
477 #endif
478 };
479 
480 #ifdef CONFIG_SMP
481 
482 /*
483  * We add the notion of a root-domain which will be used to define per-domain
484  * variables. Each exclusive cpuset essentially defines an island domain by
485  * fully partitioning the member cpus from any other cpuset. Whenever a new
486  * exclusive cpuset is created, we also create and attach a new root-domain
487  * object.
488  *
489  */
490 struct root_domain {
491 	atomic_t refcount;
492 	atomic_t rto_count;
493 	struct rcu_head rcu;
494 	cpumask_var_t span;
495 	cpumask_var_t online;
496 
497 	/*
498 	 * The bit corresponding to a CPU gets set here if such CPU has more
499 	 * than one runnable -deadline task (as it is below for RT tasks).
500 	 */
501 	cpumask_var_t dlo_mask;
502 	atomic_t dlo_count;
503 	struct dl_bw dl_bw;
504 	struct cpudl cpudl;
505 
506 	/*
507 	 * The "RT overload" flag: it gets set if a CPU has more than
508 	 * one runnable RT task.
509 	 */
510 	cpumask_var_t rto_mask;
511 	struct cpupri cpupri;
512 };
513 
514 extern struct root_domain def_root_domain;
515 
516 #endif /* CONFIG_SMP */
517 
518 /*
519  * This is the main, per-CPU runqueue data structure.
520  *
521  * Locking rule: those places that want to lock multiple runqueues
522  * (such as the load balancing or the thread migration code), lock
523  * acquire operations must be ordered by ascending &runqueue.
524  */
525 struct rq {
526 	/* runqueue lock: */
527 	raw_spinlock_t lock;
528 
529 	/*
530 	 * nr_running and cpu_load should be in the same cacheline because
531 	 * remote CPUs use both these fields when doing load calculation.
532 	 */
533 	unsigned int nr_running;
534 #ifdef CONFIG_NUMA_BALANCING
535 	unsigned int nr_numa_running;
536 	unsigned int nr_preferred_running;
537 #endif
538 	#define CPU_LOAD_IDX_MAX 5
539 	unsigned long cpu_load[CPU_LOAD_IDX_MAX];
540 	unsigned long last_load_update_tick;
541 #ifdef CONFIG_NO_HZ_COMMON
542 	u64 nohz_stamp;
543 	unsigned long nohz_flags;
544 #endif
545 #ifdef CONFIG_NO_HZ_FULL
546 	unsigned long last_sched_tick;
547 #endif
548 	int skip_clock_update;
549 
550 	/* capture load from *all* tasks on this cpu: */
551 	struct load_weight load;
552 	unsigned long nr_load_updates;
553 	u64 nr_switches;
554 
555 	struct cfs_rq cfs;
556 	struct rt_rq rt;
557 	struct dl_rq dl;
558 
559 #ifdef CONFIG_FAIR_GROUP_SCHED
560 	/* list of leaf cfs_rq on this cpu: */
561 	struct list_head leaf_cfs_rq_list;
562 #endif /* CONFIG_FAIR_GROUP_SCHED */
563 
564 #ifdef CONFIG_RT_GROUP_SCHED
565 	struct list_head leaf_rt_rq_list;
566 #endif
567 
568 	/*
569 	 * This is part of a global counter where only the total sum
570 	 * over all CPUs matters. A task can increase this counter on
571 	 * one CPU and if it got migrated afterwards it may decrease
572 	 * it on another CPU. Always updated under the runqueue lock:
573 	 */
574 	unsigned long nr_uninterruptible;
575 
576 	struct task_struct *curr, *idle, *stop;
577 	unsigned long next_balance;
578 	struct mm_struct *prev_mm;
579 
580 	u64 clock;
581 	u64 clock_task;
582 
583 	atomic_t nr_iowait;
584 
585 #ifdef CONFIG_SMP
586 	struct root_domain *rd;
587 	struct sched_domain *sd;
588 
589 	unsigned long cpu_power;
590 
591 	unsigned char idle_balance;
592 	/* For active balancing */
593 	int post_schedule;
594 	int active_balance;
595 	int push_cpu;
596 	struct cpu_stop_work active_balance_work;
597 	/* cpu of this runqueue: */
598 	int cpu;
599 	int online;
600 
601 	struct list_head cfs_tasks;
602 
603 	u64 rt_avg;
604 	u64 age_stamp;
605 	u64 idle_stamp;
606 	u64 avg_idle;
607 
608 	/* This is used to determine avg_idle's max value */
609 	u64 max_idle_balance_cost;
610 #endif
611 
612 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
613 	u64 prev_irq_time;
614 #endif
615 #ifdef CONFIG_PARAVIRT
616 	u64 prev_steal_time;
617 #endif
618 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
619 	u64 prev_steal_time_rq;
620 #endif
621 
622 	/* calc_load related fields */
623 	unsigned long calc_load_update;
624 	long calc_load_active;
625 
626 #ifdef CONFIG_SCHED_HRTICK
627 #ifdef CONFIG_SMP
628 	int hrtick_csd_pending;
629 	struct call_single_data hrtick_csd;
630 #endif
631 	struct hrtimer hrtick_timer;
632 #endif
633 
634 #ifdef CONFIG_SCHEDSTATS
635 	/* latency stats */
636 	struct sched_info rq_sched_info;
637 	unsigned long long rq_cpu_time;
638 	/* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
639 
640 	/* sys_sched_yield() stats */
641 	unsigned int yld_count;
642 
643 	/* schedule() stats */
644 	unsigned int sched_count;
645 	unsigned int sched_goidle;
646 
647 	/* try_to_wake_up() stats */
648 	unsigned int ttwu_count;
649 	unsigned int ttwu_local;
650 #endif
651 
652 #ifdef CONFIG_SMP
653 	struct llist_head wake_list;
654 #endif
655 
656 	struct sched_avg avg;
657 };
658 
659 static inline int cpu_of(struct rq *rq)
660 {
661 #ifdef CONFIG_SMP
662 	return rq->cpu;
663 #else
664 	return 0;
665 #endif
666 }
667 
668 DECLARE_PER_CPU(struct rq, runqueues);
669 
670 #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
671 #define this_rq()		(&__get_cpu_var(runqueues))
672 #define task_rq(p)		cpu_rq(task_cpu(p))
673 #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
674 #define raw_rq()		(&__raw_get_cpu_var(runqueues))
675 
676 static inline u64 rq_clock(struct rq *rq)
677 {
678 	return rq->clock;
679 }
680 
681 static inline u64 rq_clock_task(struct rq *rq)
682 {
683 	return rq->clock_task;
684 }
685 
686 #ifdef CONFIG_NUMA_BALANCING
687 extern void sched_setnuma(struct task_struct *p, int node);
688 extern int migrate_task_to(struct task_struct *p, int cpu);
689 extern int migrate_swap(struct task_struct *, struct task_struct *);
690 #endif /* CONFIG_NUMA_BALANCING */
691 
692 #ifdef CONFIG_SMP
693 
694 #define rcu_dereference_check_sched_domain(p) \
695 	rcu_dereference_check((p), \
696 			      lockdep_is_held(&sched_domains_mutex))
697 
698 /*
699  * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
700  * See detach_destroy_domains: synchronize_sched for details.
701  *
702  * The domain tree of any CPU may only be accessed from within
703  * preempt-disabled sections.
704  */
705 #define for_each_domain(cpu, __sd) \
706 	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
707 			__sd; __sd = __sd->parent)
708 
709 #define for_each_lower_domain(sd) for (; sd; sd = sd->child)
710 
711 /**
712  * highest_flag_domain - Return highest sched_domain containing flag.
713  * @cpu:	The cpu whose highest level of sched domain is to
714  *		be returned.
715  * @flag:	The flag to check for the highest sched_domain
716  *		for the given cpu.
717  *
718  * Returns the highest sched_domain of a cpu which contains the given flag.
719  */
720 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
721 {
722 	struct sched_domain *sd, *hsd = NULL;
723 
724 	for_each_domain(cpu, sd) {
725 		if (!(sd->flags & flag))
726 			break;
727 		hsd = sd;
728 	}
729 
730 	return hsd;
731 }
732 
733 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
734 {
735 	struct sched_domain *sd;
736 
737 	for_each_domain(cpu, sd) {
738 		if (sd->flags & flag)
739 			break;
740 	}
741 
742 	return sd;
743 }
744 
745 DECLARE_PER_CPU(struct sched_domain *, sd_llc);
746 DECLARE_PER_CPU(int, sd_llc_size);
747 DECLARE_PER_CPU(int, sd_llc_id);
748 DECLARE_PER_CPU(struct sched_domain *, sd_numa);
749 DECLARE_PER_CPU(struct sched_domain *, sd_busy);
750 DECLARE_PER_CPU(struct sched_domain *, sd_asym);
751 
752 struct sched_group_power {
753 	atomic_t ref;
754 	/*
755 	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
756 	 * single CPU.
757 	 */
758 	unsigned int power, power_orig;
759 	unsigned long next_update;
760 	int imbalance; /* XXX unrelated to power but shared group state */
761 	/*
762 	 * Number of busy cpus in this group.
763 	 */
764 	atomic_t nr_busy_cpus;
765 
766 	unsigned long cpumask[0]; /* iteration mask */
767 };
768 
769 struct sched_group {
770 	struct sched_group *next;	/* Must be a circular list */
771 	atomic_t ref;
772 
773 	unsigned int group_weight;
774 	struct sched_group_power *sgp;
775 
776 	/*
777 	 * The CPUs this group covers.
778 	 *
779 	 * NOTE: this field is variable length. (Allocated dynamically
780 	 * by attaching extra space to the end of the structure,
781 	 * depending on how many CPUs the kernel has booted up with)
782 	 */
783 	unsigned long cpumask[0];
784 };
785 
786 static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
787 {
788 	return to_cpumask(sg->cpumask);
789 }
790 
791 /*
792  * cpumask masking which cpus in the group are allowed to iterate up the domain
793  * tree.
794  */
795 static inline struct cpumask *sched_group_mask(struct sched_group *sg)
796 {
797 	return to_cpumask(sg->sgp->cpumask);
798 }
799 
800 /**
801  * group_first_cpu - Returns the first cpu in the cpumask of a sched_group.
802  * @group: The group whose first cpu is to be returned.
803  */
804 static inline unsigned int group_first_cpu(struct sched_group *group)
805 {
806 	return cpumask_first(sched_group_cpus(group));
807 }
808 
809 extern int group_balance_cpu(struct sched_group *sg);
810 
811 #endif /* CONFIG_SMP */
812 
813 #include "stats.h"
814 #include "auto_group.h"
815 
816 #ifdef CONFIG_CGROUP_SCHED
817 
818 /*
819  * Return the group to which this tasks belongs.
820  *
821  * We cannot use task_css() and friends because the cgroup subsystem
822  * changes that value before the cgroup_subsys::attach() method is called,
823  * therefore we cannot pin it and might observe the wrong value.
824  *
825  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
826  * core changes this before calling sched_move_task().
827  *
828  * Instead we use a 'copy' which is updated from sched_move_task() while
829  * holding both task_struct::pi_lock and rq::lock.
830  */
831 static inline struct task_group *task_group(struct task_struct *p)
832 {
833 	return p->sched_task_group;
834 }
835 
836 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
837 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
838 {
839 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
840 	struct task_group *tg = task_group(p);
841 #endif
842 
843 #ifdef CONFIG_FAIR_GROUP_SCHED
844 	p->se.cfs_rq = tg->cfs_rq[cpu];
845 	p->se.parent = tg->se[cpu];
846 #endif
847 
848 #ifdef CONFIG_RT_GROUP_SCHED
849 	p->rt.rt_rq  = tg->rt_rq[cpu];
850 	p->rt.parent = tg->rt_se[cpu];
851 #endif
852 }
853 
854 #else /* CONFIG_CGROUP_SCHED */
855 
856 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
857 static inline struct task_group *task_group(struct task_struct *p)
858 {
859 	return NULL;
860 }
861 
862 #endif /* CONFIG_CGROUP_SCHED */
863 
864 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
865 {
866 	set_task_rq(p, cpu);
867 #ifdef CONFIG_SMP
868 	/*
869 	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
870 	 * successfuly executed on another CPU. We must ensure that updates of
871 	 * per-task data have been completed by this moment.
872 	 */
873 	smp_wmb();
874 	task_thread_info(p)->cpu = cpu;
875 	p->wake_cpu = cpu;
876 #endif
877 }
878 
879 /*
880  * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
881  */
882 #ifdef CONFIG_SCHED_DEBUG
883 # include <linux/static_key.h>
884 # define const_debug __read_mostly
885 #else
886 # define const_debug const
887 #endif
888 
889 extern const_debug unsigned int sysctl_sched_features;
890 
891 #define SCHED_FEAT(name, enabled)	\
892 	__SCHED_FEAT_##name ,
893 
894 enum {
895 #include "features.h"
896 	__SCHED_FEAT_NR,
897 };
898 
899 #undef SCHED_FEAT
900 
901 #if defined(CONFIG_SCHED_DEBUG) && defined(HAVE_JUMP_LABEL)
902 static __always_inline bool static_branch__true(struct static_key *key)
903 {
904 	return static_key_true(key); /* Not out of line branch. */
905 }
906 
907 static __always_inline bool static_branch__false(struct static_key *key)
908 {
909 	return static_key_false(key); /* Out of line branch. */
910 }
911 
912 #define SCHED_FEAT(name, enabled)					\
913 static __always_inline bool static_branch_##name(struct static_key *key) \
914 {									\
915 	return static_branch__##enabled(key);				\
916 }
917 
918 #include "features.h"
919 
920 #undef SCHED_FEAT
921 
922 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
923 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
924 #else /* !(SCHED_DEBUG && HAVE_JUMP_LABEL) */
925 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
926 #endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */
927 
928 #ifdef CONFIG_NUMA_BALANCING
929 #define sched_feat_numa(x) sched_feat(x)
930 #ifdef CONFIG_SCHED_DEBUG
931 #define numabalancing_enabled sched_feat_numa(NUMA)
932 #else
933 extern bool numabalancing_enabled;
934 #endif /* CONFIG_SCHED_DEBUG */
935 #else
936 #define sched_feat_numa(x) (0)
937 #define numabalancing_enabled (0)
938 #endif /* CONFIG_NUMA_BALANCING */
939 
940 static inline u64 global_rt_period(void)
941 {
942 	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
943 }
944 
945 static inline u64 global_rt_runtime(void)
946 {
947 	if (sysctl_sched_rt_runtime < 0)
948 		return RUNTIME_INF;
949 
950 	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
951 }
952 
953 static inline int task_current(struct rq *rq, struct task_struct *p)
954 {
955 	return rq->curr == p;
956 }
957 
958 static inline int task_running(struct rq *rq, struct task_struct *p)
959 {
960 #ifdef CONFIG_SMP
961 	return p->on_cpu;
962 #else
963 	return task_current(rq, p);
964 #endif
965 }
966 
967 
968 #ifndef prepare_arch_switch
969 # define prepare_arch_switch(next)	do { } while (0)
970 #endif
971 #ifndef finish_arch_switch
972 # define finish_arch_switch(prev)	do { } while (0)
973 #endif
974 #ifndef finish_arch_post_lock_switch
975 # define finish_arch_post_lock_switch()	do { } while (0)
976 #endif
977 
978 #ifndef __ARCH_WANT_UNLOCKED_CTXSW
979 static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
980 {
981 #ifdef CONFIG_SMP
982 	/*
983 	 * We can optimise this out completely for !SMP, because the
984 	 * SMP rebalancing from interrupt is the only thing that cares
985 	 * here.
986 	 */
987 	next->on_cpu = 1;
988 #endif
989 }
990 
991 static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
992 {
993 #ifdef CONFIG_SMP
994 	/*
995 	 * After ->on_cpu is cleared, the task can be moved to a different CPU.
996 	 * We must ensure this doesn't happen until the switch is completely
997 	 * finished.
998 	 */
999 	smp_wmb();
1000 	prev->on_cpu = 0;
1001 #endif
1002 #ifdef CONFIG_DEBUG_SPINLOCK
1003 	/* this is a valid case when another task releases the spinlock */
1004 	rq->lock.owner = current;
1005 #endif
1006 	/*
1007 	 * If we are tracking spinlock dependencies then we have to
1008 	 * fix up the runqueue lock - which gets 'carried over' from
1009 	 * prev into current:
1010 	 */
1011 	spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_);
1012 
1013 	raw_spin_unlock_irq(&rq->lock);
1014 }
1015 
1016 #else /* __ARCH_WANT_UNLOCKED_CTXSW */
1017 static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
1018 {
1019 #ifdef CONFIG_SMP
1020 	/*
1021 	 * We can optimise this out completely for !SMP, because the
1022 	 * SMP rebalancing from interrupt is the only thing that cares
1023 	 * here.
1024 	 */
1025 	next->on_cpu = 1;
1026 #endif
1027 	raw_spin_unlock(&rq->lock);
1028 }
1029 
1030 static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
1031 {
1032 #ifdef CONFIG_SMP
1033 	/*
1034 	 * After ->on_cpu is cleared, the task can be moved to a different CPU.
1035 	 * We must ensure this doesn't happen until the switch is completely
1036 	 * finished.
1037 	 */
1038 	smp_wmb();
1039 	prev->on_cpu = 0;
1040 #endif
1041 	local_irq_enable();
1042 }
1043 #endif /* __ARCH_WANT_UNLOCKED_CTXSW */
1044 
1045 /*
1046  * wake flags
1047  */
1048 #define WF_SYNC		0x01		/* waker goes to sleep after wakeup */
1049 #define WF_FORK		0x02		/* child wakeup after fork */
1050 #define WF_MIGRATED	0x4		/* internal use, task got migrated */
1051 
1052 /*
1053  * To aid in avoiding the subversion of "niceness" due to uneven distribution
1054  * of tasks with abnormal "nice" values across CPUs the contribution that
1055  * each task makes to its run queue's load is weighted according to its
1056  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
1057  * scaled version of the new time slice allocation that they receive on time
1058  * slice expiry etc.
1059  */
1060 
1061 #define WEIGHT_IDLEPRIO                3
1062 #define WMULT_IDLEPRIO         1431655765
1063 
1064 /*
1065  * Nice levels are multiplicative, with a gentle 10% change for every
1066  * nice level changed. I.e. when a CPU-bound task goes from nice 0 to
1067  * nice 1, it will get ~10% less CPU time than another CPU-bound task
1068  * that remained on nice 0.
1069  *
1070  * The "10% effect" is relative and cumulative: from _any_ nice level,
1071  * if you go up 1 level, it's -10% CPU usage, if you go down 1 level
1072  * it's +10% CPU usage. (to achieve that we use a multiplier of 1.25.
1073  * If a task goes up by ~10% and another task goes down by ~10% then
1074  * the relative distance between them is ~25%.)
1075  */
1076 static const int prio_to_weight[40] = {
1077  /* -20 */     88761,     71755,     56483,     46273,     36291,
1078  /* -15 */     29154,     23254,     18705,     14949,     11916,
1079  /* -10 */      9548,      7620,      6100,      4904,      3906,
1080  /*  -5 */      3121,      2501,      1991,      1586,      1277,
1081  /*   0 */      1024,       820,       655,       526,       423,
1082  /*   5 */       335,       272,       215,       172,       137,
1083  /*  10 */       110,        87,        70,        56,        45,
1084  /*  15 */        36,        29,        23,        18,        15,
1085 };
1086 
1087 /*
1088  * Inverse (2^32/x) values of the prio_to_weight[] array, precalculated.
1089  *
1090  * In cases where the weight does not change often, we can use the
1091  * precalculated inverse to speed up arithmetics by turning divisions
1092  * into multiplications:
1093  */
1094 static const u32 prio_to_wmult[40] = {
1095  /* -20 */     48388,     59856,     76040,     92818,    118348,
1096  /* -15 */    147320,    184698,    229616,    287308,    360437,
1097  /* -10 */    449829,    563644,    704093,    875809,   1099582,
1098  /*  -5 */   1376151,   1717300,   2157191,   2708050,   3363326,
1099  /*   0 */   4194304,   5237765,   6557202,   8165337,  10153587,
1100  /*   5 */  12820798,  15790321,  19976592,  24970740,  31350126,
1101  /*  10 */  39045157,  49367440,  61356676,  76695844,  95443717,
1102  /*  15 */ 119304647, 148102320, 186737708, 238609294, 286331153,
1103 };
1104 
1105 #define ENQUEUE_WAKEUP		1
1106 #define ENQUEUE_HEAD		2
1107 #ifdef CONFIG_SMP
1108 #define ENQUEUE_WAKING		4	/* sched_class::task_waking was called */
1109 #else
1110 #define ENQUEUE_WAKING		0
1111 #endif
1112 #define ENQUEUE_REPLENISH	8
1113 
1114 #define DEQUEUE_SLEEP		1
1115 
1116 struct sched_class {
1117 	const struct sched_class *next;
1118 
1119 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1120 	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1121 	void (*yield_task) (struct rq *rq);
1122 	bool (*yield_to_task) (struct rq *rq, struct task_struct *p, bool preempt);
1123 
1124 	void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
1125 
1126 	struct task_struct * (*pick_next_task) (struct rq *rq);
1127 	void (*put_prev_task) (struct rq *rq, struct task_struct *p);
1128 
1129 #ifdef CONFIG_SMP
1130 	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
1131 	void (*migrate_task_rq)(struct task_struct *p, int next_cpu);
1132 
1133 	void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
1134 	void (*post_schedule) (struct rq *this_rq);
1135 	void (*task_waking) (struct task_struct *task);
1136 	void (*task_woken) (struct rq *this_rq, struct task_struct *task);
1137 
1138 	void (*set_cpus_allowed)(struct task_struct *p,
1139 				 const struct cpumask *newmask);
1140 
1141 	void (*rq_online)(struct rq *rq);
1142 	void (*rq_offline)(struct rq *rq);
1143 #endif
1144 
1145 	void (*set_curr_task) (struct rq *rq);
1146 	void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1147 	void (*task_fork) (struct task_struct *p);
1148 	void (*task_dead) (struct task_struct *p);
1149 
1150 	void (*switched_from) (struct rq *this_rq, struct task_struct *task);
1151 	void (*switched_to) (struct rq *this_rq, struct task_struct *task);
1152 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1153 			     int oldprio);
1154 
1155 	unsigned int (*get_rr_interval) (struct rq *rq,
1156 					 struct task_struct *task);
1157 
1158 #ifdef CONFIG_FAIR_GROUP_SCHED
1159 	void (*task_move_group) (struct task_struct *p, int on_rq);
1160 #endif
1161 };
1162 
1163 #define sched_class_highest (&stop_sched_class)
1164 #define for_each_class(class) \
1165    for (class = sched_class_highest; class; class = class->next)
1166 
1167 extern const struct sched_class stop_sched_class;
1168 extern const struct sched_class dl_sched_class;
1169 extern const struct sched_class rt_sched_class;
1170 extern const struct sched_class fair_sched_class;
1171 extern const struct sched_class idle_sched_class;
1172 
1173 
1174 #ifdef CONFIG_SMP
1175 
1176 extern void update_group_power(struct sched_domain *sd, int cpu);
1177 
1178 extern void trigger_load_balance(struct rq *rq);
1179 extern void idle_balance(int this_cpu, struct rq *this_rq);
1180 
1181 extern void idle_enter_fair(struct rq *this_rq);
1182 extern void idle_exit_fair(struct rq *this_rq);
1183 
1184 #else	/* CONFIG_SMP */
1185 
1186 static inline void idle_balance(int cpu, struct rq *rq)
1187 {
1188 }
1189 
1190 #endif
1191 
1192 extern void sysrq_sched_debug_show(void);
1193 extern void sched_init_granularity(void);
1194 extern void update_max_interval(void);
1195 
1196 extern void init_sched_dl_class(void);
1197 extern void init_sched_rt_class(void);
1198 extern void init_sched_fair_class(void);
1199 extern void init_sched_dl_class(void);
1200 
1201 extern void resched_task(struct task_struct *p);
1202 extern void resched_cpu(int cpu);
1203 
1204 extern struct rt_bandwidth def_rt_bandwidth;
1205 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
1206 
1207 extern struct dl_bandwidth def_dl_bandwidth;
1208 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
1209 extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
1210 
1211 unsigned long to_ratio(u64 period, u64 runtime);
1212 
1213 extern void update_idle_cpu_load(struct rq *this_rq);
1214 
1215 extern void init_task_runnable_average(struct task_struct *p);
1216 
1217 #ifdef CONFIG_PARAVIRT
1218 static inline u64 steal_ticks(u64 steal)
1219 {
1220 	if (unlikely(steal > NSEC_PER_SEC))
1221 		return div_u64(steal, TICK_NSEC);
1222 
1223 	return __iter_div_u64_rem(steal, TICK_NSEC, &steal);
1224 }
1225 #endif
1226 
1227 static inline void inc_nr_running(struct rq *rq)
1228 {
1229 	rq->nr_running++;
1230 
1231 #ifdef CONFIG_NO_HZ_FULL
1232 	if (rq->nr_running == 2) {
1233 		if (tick_nohz_full_cpu(rq->cpu)) {
1234 			/* Order rq->nr_running write against the IPI */
1235 			smp_wmb();
1236 			smp_send_reschedule(rq->cpu);
1237 		}
1238        }
1239 #endif
1240 }
1241 
1242 static inline void dec_nr_running(struct rq *rq)
1243 {
1244 	rq->nr_running--;
1245 }
1246 
1247 static inline void rq_last_tick_reset(struct rq *rq)
1248 {
1249 #ifdef CONFIG_NO_HZ_FULL
1250 	rq->last_sched_tick = jiffies;
1251 #endif
1252 }
1253 
1254 extern void update_rq_clock(struct rq *rq);
1255 
1256 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
1257 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
1258 
1259 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
1260 
1261 extern const_debug unsigned int sysctl_sched_time_avg;
1262 extern const_debug unsigned int sysctl_sched_nr_migrate;
1263 extern const_debug unsigned int sysctl_sched_migration_cost;
1264 
1265 static inline u64 sched_avg_period(void)
1266 {
1267 	return (u64)sysctl_sched_time_avg * NSEC_PER_MSEC / 2;
1268 }
1269 
1270 #ifdef CONFIG_SCHED_HRTICK
1271 
1272 /*
1273  * Use hrtick when:
1274  *  - enabled by features
1275  *  - hrtimer is actually high res
1276  */
1277 static inline int hrtick_enabled(struct rq *rq)
1278 {
1279 	if (!sched_feat(HRTICK))
1280 		return 0;
1281 	if (!cpu_active(cpu_of(rq)))
1282 		return 0;
1283 	return hrtimer_is_hres_active(&rq->hrtick_timer);
1284 }
1285 
1286 void hrtick_start(struct rq *rq, u64 delay);
1287 
1288 #else
1289 
1290 static inline int hrtick_enabled(struct rq *rq)
1291 {
1292 	return 0;
1293 }
1294 
1295 #endif /* CONFIG_SCHED_HRTICK */
1296 
1297 #ifdef CONFIG_SMP
1298 extern void sched_avg_update(struct rq *rq);
1299 static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
1300 {
1301 	rq->rt_avg += rt_delta;
1302 	sched_avg_update(rq);
1303 }
1304 #else
1305 static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { }
1306 static inline void sched_avg_update(struct rq *rq) { }
1307 #endif
1308 
1309 extern void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period);
1310 
1311 #ifdef CONFIG_SMP
1312 #ifdef CONFIG_PREEMPT
1313 
1314 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2);
1315 
1316 /*
1317  * fair double_lock_balance: Safely acquires both rq->locks in a fair
1318  * way at the expense of forcing extra atomic operations in all
1319  * invocations.  This assures that the double_lock is acquired using the
1320  * same underlying policy as the spinlock_t on this architecture, which
1321  * reduces latency compared to the unfair variant below.  However, it
1322  * also adds more overhead and therefore may reduce throughput.
1323  */
1324 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1325 	__releases(this_rq->lock)
1326 	__acquires(busiest->lock)
1327 	__acquires(this_rq->lock)
1328 {
1329 	raw_spin_unlock(&this_rq->lock);
1330 	double_rq_lock(this_rq, busiest);
1331 
1332 	return 1;
1333 }
1334 
1335 #else
1336 /*
1337  * Unfair double_lock_balance: Optimizes throughput at the expense of
1338  * latency by eliminating extra atomic operations when the locks are
1339  * already in proper order on entry.  This favors lower cpu-ids and will
1340  * grant the double lock to lower cpus over higher ids under contention,
1341  * regardless of entry order into the function.
1342  */
1343 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1344 	__releases(this_rq->lock)
1345 	__acquires(busiest->lock)
1346 	__acquires(this_rq->lock)
1347 {
1348 	int ret = 0;
1349 
1350 	if (unlikely(!raw_spin_trylock(&busiest->lock))) {
1351 		if (busiest < this_rq) {
1352 			raw_spin_unlock(&this_rq->lock);
1353 			raw_spin_lock(&busiest->lock);
1354 			raw_spin_lock_nested(&this_rq->lock,
1355 					      SINGLE_DEPTH_NESTING);
1356 			ret = 1;
1357 		} else
1358 			raw_spin_lock_nested(&busiest->lock,
1359 					      SINGLE_DEPTH_NESTING);
1360 	}
1361 	return ret;
1362 }
1363 
1364 #endif /* CONFIG_PREEMPT */
1365 
1366 /*
1367  * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
1368  */
1369 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
1370 {
1371 	if (unlikely(!irqs_disabled())) {
1372 		/* printk() doesn't work good under rq->lock */
1373 		raw_spin_unlock(&this_rq->lock);
1374 		BUG_ON(1);
1375 	}
1376 
1377 	return _double_lock_balance(this_rq, busiest);
1378 }
1379 
1380 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
1381 	__releases(busiest->lock)
1382 {
1383 	raw_spin_unlock(&busiest->lock);
1384 	lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
1385 }
1386 
1387 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
1388 {
1389 	if (l1 > l2)
1390 		swap(l1, l2);
1391 
1392 	spin_lock(l1);
1393 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1394 }
1395 
1396 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
1397 {
1398 	if (l1 > l2)
1399 		swap(l1, l2);
1400 
1401 	raw_spin_lock(l1);
1402 	raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1403 }
1404 
1405 /*
1406  * double_rq_lock - safely lock two runqueues
1407  *
1408  * Note this does not disable interrupts like task_rq_lock,
1409  * you need to do so manually before calling.
1410  */
1411 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
1412 	__acquires(rq1->lock)
1413 	__acquires(rq2->lock)
1414 {
1415 	BUG_ON(!irqs_disabled());
1416 	if (rq1 == rq2) {
1417 		raw_spin_lock(&rq1->lock);
1418 		__acquire(rq2->lock);	/* Fake it out ;) */
1419 	} else {
1420 		if (rq1 < rq2) {
1421 			raw_spin_lock(&rq1->lock);
1422 			raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
1423 		} else {
1424 			raw_spin_lock(&rq2->lock);
1425 			raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
1426 		}
1427 	}
1428 }
1429 
1430 /*
1431  * double_rq_unlock - safely unlock two runqueues
1432  *
1433  * Note this does not restore interrupts like task_rq_unlock,
1434  * you need to do so manually after calling.
1435  */
1436 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
1437 	__releases(rq1->lock)
1438 	__releases(rq2->lock)
1439 {
1440 	raw_spin_unlock(&rq1->lock);
1441 	if (rq1 != rq2)
1442 		raw_spin_unlock(&rq2->lock);
1443 	else
1444 		__release(rq2->lock);
1445 }
1446 
1447 #else /* CONFIG_SMP */
1448 
1449 /*
1450  * double_rq_lock - safely lock two runqueues
1451  *
1452  * Note this does not disable interrupts like task_rq_lock,
1453  * you need to do so manually before calling.
1454  */
1455 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
1456 	__acquires(rq1->lock)
1457 	__acquires(rq2->lock)
1458 {
1459 	BUG_ON(!irqs_disabled());
1460 	BUG_ON(rq1 != rq2);
1461 	raw_spin_lock(&rq1->lock);
1462 	__acquire(rq2->lock);	/* Fake it out ;) */
1463 }
1464 
1465 /*
1466  * double_rq_unlock - safely unlock two runqueues
1467  *
1468  * Note this does not restore interrupts like task_rq_unlock,
1469  * you need to do so manually after calling.
1470  */
1471 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
1472 	__releases(rq1->lock)
1473 	__releases(rq2->lock)
1474 {
1475 	BUG_ON(rq1 != rq2);
1476 	raw_spin_unlock(&rq1->lock);
1477 	__release(rq2->lock);
1478 }
1479 
1480 #endif
1481 
1482 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
1483 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
1484 extern void print_cfs_stats(struct seq_file *m, int cpu);
1485 extern void print_rt_stats(struct seq_file *m, int cpu);
1486 
1487 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
1488 extern void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq);
1489 extern void init_dl_rq(struct dl_rq *dl_rq, struct rq *rq);
1490 
1491 extern void cfs_bandwidth_usage_inc(void);
1492 extern void cfs_bandwidth_usage_dec(void);
1493 
1494 #ifdef CONFIG_NO_HZ_COMMON
1495 enum rq_nohz_flag_bits {
1496 	NOHZ_TICK_STOPPED,
1497 	NOHZ_BALANCE_KICK,
1498 };
1499 
1500 #define nohz_flags(cpu)	(&cpu_rq(cpu)->nohz_flags)
1501 #endif
1502 
1503 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1504 
1505 DECLARE_PER_CPU(u64, cpu_hardirq_time);
1506 DECLARE_PER_CPU(u64, cpu_softirq_time);
1507 
1508 #ifndef CONFIG_64BIT
1509 DECLARE_PER_CPU(seqcount_t, irq_time_seq);
1510 
1511 static inline void irq_time_write_begin(void)
1512 {
1513 	__this_cpu_inc(irq_time_seq.sequence);
1514 	smp_wmb();
1515 }
1516 
1517 static inline void irq_time_write_end(void)
1518 {
1519 	smp_wmb();
1520 	__this_cpu_inc(irq_time_seq.sequence);
1521 }
1522 
1523 static inline u64 irq_time_read(int cpu)
1524 {
1525 	u64 irq_time;
1526 	unsigned seq;
1527 
1528 	do {
1529 		seq = read_seqcount_begin(&per_cpu(irq_time_seq, cpu));
1530 		irq_time = per_cpu(cpu_softirq_time, cpu) +
1531 			   per_cpu(cpu_hardirq_time, cpu);
1532 	} while (read_seqcount_retry(&per_cpu(irq_time_seq, cpu), seq));
1533 
1534 	return irq_time;
1535 }
1536 #else /* CONFIG_64BIT */
1537 static inline void irq_time_write_begin(void)
1538 {
1539 }
1540 
1541 static inline void irq_time_write_end(void)
1542 {
1543 }
1544 
1545 static inline u64 irq_time_read(int cpu)
1546 {
1547 	return per_cpu(cpu_softirq_time, cpu) + per_cpu(cpu_hardirq_time, cpu);
1548 }
1549 #endif /* CONFIG_64BIT */
1550 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
1551