xref: /openbmc/linux/kernel/sched/sched.h (revision 141e5239)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Scheduler internal types and methods:
4  */
5 #ifndef _KERNEL_SCHED_SCHED_H
6 #define _KERNEL_SCHED_SCHED_H
7 
8 #include <linux/sched/affinity.h>
9 #include <linux/sched/autogroup.h>
10 #include <linux/sched/cpufreq.h>
11 #include <linux/sched/deadline.h>
12 #include <linux/sched.h>
13 #include <linux/sched/loadavg.h>
14 #include <linux/sched/mm.h>
15 #include <linux/sched/rseq_api.h>
16 #include <linux/sched/signal.h>
17 #include <linux/sched/smt.h>
18 #include <linux/sched/stat.h>
19 #include <linux/sched/sysctl.h>
20 #include <linux/sched/task_flags.h>
21 #include <linux/sched/task.h>
22 #include <linux/sched/topology.h>
23 
24 #include <linux/atomic.h>
25 #include <linux/bitmap.h>
26 #include <linux/bug.h>
27 #include <linux/capability.h>
28 #include <linux/cgroup_api.h>
29 #include <linux/cgroup.h>
30 #include <linux/cpufreq.h>
31 #include <linux/cpumask_api.h>
32 #include <linux/ctype.h>
33 #include <linux/file.h>
34 #include <linux/fs_api.h>
35 #include <linux/hrtimer_api.h>
36 #include <linux/interrupt.h>
37 #include <linux/irq_work.h>
38 #include <linux/jiffies.h>
39 #include <linux/kref_api.h>
40 #include <linux/kthread.h>
41 #include <linux/ktime_api.h>
42 #include <linux/lockdep_api.h>
43 #include <linux/lockdep.h>
44 #include <linux/minmax.h>
45 #include <linux/mm.h>
46 #include <linux/module.h>
47 #include <linux/mutex_api.h>
48 #include <linux/plist.h>
49 #include <linux/poll.h>
50 #include <linux/proc_fs.h>
51 #include <linux/profile.h>
52 #include <linux/psi.h>
53 #include <linux/rcupdate.h>
54 #include <linux/seq_file.h>
55 #include <linux/seqlock.h>
56 #include <linux/softirq.h>
57 #include <linux/spinlock_api.h>
58 #include <linux/static_key.h>
59 #include <linux/stop_machine.h>
60 #include <linux/syscalls_api.h>
61 #include <linux/syscalls.h>
62 #include <linux/tick.h>
63 #include <linux/topology.h>
64 #include <linux/types.h>
65 #include <linux/u64_stats_sync_api.h>
66 #include <linux/uaccess.h>
67 #include <linux/wait_api.h>
68 #include <linux/wait_bit.h>
69 #include <linux/workqueue_api.h>
70 
71 #include <trace/events/power.h>
72 #include <trace/events/sched.h>
73 
74 #include "../workqueue_internal.h"
75 
76 #ifdef CONFIG_CGROUP_SCHED
77 #include <linux/cgroup.h>
78 #include <linux/psi.h>
79 #endif
80 
81 #ifdef CONFIG_SCHED_DEBUG
82 # include <linux/static_key.h>
83 #endif
84 
85 #ifdef CONFIG_PARAVIRT
86 # include <asm/paravirt.h>
87 # include <asm/paravirt_api_clock.h>
88 #endif
89 
90 #include "cpupri.h"
91 #include "cpudeadline.h"
92 
93 #ifdef CONFIG_SCHED_DEBUG
94 # define SCHED_WARN_ON(x)      WARN_ONCE(x, #x)
95 #else
96 # define SCHED_WARN_ON(x)      ({ (void)(x), 0; })
97 #endif
98 
99 struct rq;
100 struct cpuidle_state;
101 
102 /* task_struct::on_rq states: */
103 #define TASK_ON_RQ_QUEUED	1
104 #define TASK_ON_RQ_MIGRATING	2
105 
106 extern __read_mostly int scheduler_running;
107 
108 extern unsigned long calc_load_update;
109 extern atomic_long_t calc_load_tasks;
110 
111 extern void calc_global_load_tick(struct rq *this_rq);
112 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
113 
114 extern void call_trace_sched_update_nr_running(struct rq *rq, int count);
115 /*
116  * Helpers for converting nanosecond timing to jiffy resolution
117  */
118 #define NS_TO_JIFFIES(TIME)	((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
119 
120 /*
121  * Increase resolution of nice-level calculations for 64-bit architectures.
122  * The extra resolution improves shares distribution and load balancing of
123  * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
124  * hierarchies, especially on larger systems. This is not a user-visible change
125  * and does not change the user-interface for setting shares/weights.
126  *
127  * We increase resolution only if we have enough bits to allow this increased
128  * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
129  * are pretty high and the returns do not justify the increased costs.
130  *
131  * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
132  * increase coverage and consistency always enable it on 64-bit platforms.
133  */
134 #ifdef CONFIG_64BIT
135 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
136 # define scale_load(w)		((w) << SCHED_FIXEDPOINT_SHIFT)
137 # define scale_load_down(w) \
138 ({ \
139 	unsigned long __w = (w); \
140 	if (__w) \
141 		__w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \
142 	__w; \
143 })
144 #else
145 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT)
146 # define scale_load(w)		(w)
147 # define scale_load_down(w)	(w)
148 #endif
149 
150 /*
151  * Task weight (visible to users) and its load (invisible to users) have
152  * independent resolution, but they should be well calibrated. We use
153  * scale_load() and scale_load_down(w) to convert between them. The
154  * following must be true:
155  *
156  *  scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD
157  *
158  */
159 #define NICE_0_LOAD		(1L << NICE_0_LOAD_SHIFT)
160 
161 /*
162  * Single value that decides SCHED_DEADLINE internal math precision.
163  * 10 -> just above 1us
164  * 9  -> just above 0.5us
165  */
166 #define DL_SCALE		10
167 
168 /*
169  * Single value that denotes runtime == period, ie unlimited time.
170  */
171 #define RUNTIME_INF		((u64)~0ULL)
172 
173 static inline int idle_policy(int policy)
174 {
175 	return policy == SCHED_IDLE;
176 }
177 static inline int fair_policy(int policy)
178 {
179 	return policy == SCHED_NORMAL || policy == SCHED_BATCH;
180 }
181 
182 static inline int rt_policy(int policy)
183 {
184 	return policy == SCHED_FIFO || policy == SCHED_RR;
185 }
186 
187 static inline int dl_policy(int policy)
188 {
189 	return policy == SCHED_DEADLINE;
190 }
191 static inline bool valid_policy(int policy)
192 {
193 	return idle_policy(policy) || fair_policy(policy) ||
194 		rt_policy(policy) || dl_policy(policy);
195 }
196 
197 static inline int task_has_idle_policy(struct task_struct *p)
198 {
199 	return idle_policy(p->policy);
200 }
201 
202 static inline int task_has_rt_policy(struct task_struct *p)
203 {
204 	return rt_policy(p->policy);
205 }
206 
207 static inline int task_has_dl_policy(struct task_struct *p)
208 {
209 	return dl_policy(p->policy);
210 }
211 
212 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
213 
214 static inline void update_avg(u64 *avg, u64 sample)
215 {
216 	s64 diff = sample - *avg;
217 	*avg += diff / 8;
218 }
219 
220 /*
221  * Shifting a value by an exponent greater *or equal* to the size of said value
222  * is UB; cap at size-1.
223  */
224 #define shr_bound(val, shift)							\
225 	(val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1))
226 
227 /*
228  * !! For sched_setattr_nocheck() (kernel) only !!
229  *
230  * This is actually gross. :(
231  *
232  * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
233  * tasks, but still be able to sleep. We need this on platforms that cannot
234  * atomically change clock frequency. Remove once fast switching will be
235  * available on such platforms.
236  *
237  * SUGOV stands for SchedUtil GOVernor.
238  */
239 #define SCHED_FLAG_SUGOV	0x10000000
240 
241 #define SCHED_DL_FLAGS (SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV)
242 
243 static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se)
244 {
245 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
246 	return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
247 #else
248 	return false;
249 #endif
250 }
251 
252 /*
253  * Tells if entity @a should preempt entity @b.
254  */
255 static inline bool
256 dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
257 {
258 	return dl_entity_is_special(a) ||
259 	       dl_time_before(a->deadline, b->deadline);
260 }
261 
262 /*
263  * This is the priority-queue data structure of the RT scheduling class:
264  */
265 struct rt_prio_array {
266 	DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
267 	struct list_head queue[MAX_RT_PRIO];
268 };
269 
270 struct rt_bandwidth {
271 	/* nests inside the rq lock: */
272 	raw_spinlock_t		rt_runtime_lock;
273 	ktime_t			rt_period;
274 	u64			rt_runtime;
275 	struct hrtimer		rt_period_timer;
276 	unsigned int		rt_period_active;
277 };
278 
279 void __dl_clear_params(struct task_struct *p);
280 
281 struct dl_bandwidth {
282 	raw_spinlock_t		dl_runtime_lock;
283 	u64			dl_runtime;
284 	u64			dl_period;
285 };
286 
287 static inline int dl_bandwidth_enabled(void)
288 {
289 	return sysctl_sched_rt_runtime >= 0;
290 }
291 
292 /*
293  * To keep the bandwidth of -deadline tasks under control
294  * we need some place where:
295  *  - store the maximum -deadline bandwidth of each cpu;
296  *  - cache the fraction of bandwidth that is currently allocated in
297  *    each root domain;
298  *
299  * This is all done in the data structure below. It is similar to the
300  * one used for RT-throttling (rt_bandwidth), with the main difference
301  * that, since here we are only interested in admission control, we
302  * do not decrease any runtime while the group "executes", neither we
303  * need a timer to replenish it.
304  *
305  * With respect to SMP, bandwidth is given on a per root domain basis,
306  * meaning that:
307  *  - bw (< 100%) is the deadline bandwidth of each CPU;
308  *  - total_bw is the currently allocated bandwidth in each root domain;
309  */
310 struct dl_bw {
311 	raw_spinlock_t		lock;
312 	u64			bw;
313 	u64			total_bw;
314 };
315 
316 /*
317  * Verify the fitness of task @p to run on @cpu taking into account the
318  * CPU original capacity and the runtime/deadline ratio of the task.
319  *
320  * The function will return true if the CPU original capacity of the
321  * @cpu scaled by SCHED_CAPACITY_SCALE >= runtime/deadline ratio of the
322  * task and false otherwise.
323  */
324 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
325 {
326 	unsigned long cap = arch_scale_cpu_capacity(cpu);
327 
328 	return cap_scale(p->dl.dl_deadline, cap) >= p->dl.dl_runtime;
329 }
330 
331 extern void init_dl_bw(struct dl_bw *dl_b);
332 extern int  sched_dl_global_validate(void);
333 extern void sched_dl_do_global(void);
334 extern int  sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
335 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
336 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
337 extern bool __checkparam_dl(const struct sched_attr *attr);
338 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
339 extern int  dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
340 extern int  dl_cpu_busy(int cpu, struct task_struct *p);
341 
342 #ifdef CONFIG_CGROUP_SCHED
343 
344 struct cfs_rq;
345 struct rt_rq;
346 
347 extern struct list_head task_groups;
348 
349 struct cfs_bandwidth {
350 #ifdef CONFIG_CFS_BANDWIDTH
351 	raw_spinlock_t		lock;
352 	ktime_t			period;
353 	u64			quota;
354 	u64			runtime;
355 	u64			burst;
356 	u64			runtime_snap;
357 	s64			hierarchical_quota;
358 
359 	u8			idle;
360 	u8			period_active;
361 	u8			slack_started;
362 	struct hrtimer		period_timer;
363 	struct hrtimer		slack_timer;
364 	struct list_head	throttled_cfs_rq;
365 
366 	/* Statistics: */
367 	int			nr_periods;
368 	int			nr_throttled;
369 	int			nr_burst;
370 	u64			throttled_time;
371 	u64			burst_time;
372 #endif
373 };
374 
375 /* Task group related information */
376 struct task_group {
377 	struct cgroup_subsys_state css;
378 
379 #ifdef CONFIG_FAIR_GROUP_SCHED
380 	/* schedulable entities of this group on each CPU */
381 	struct sched_entity	**se;
382 	/* runqueue "owned" by this group on each CPU */
383 	struct cfs_rq		**cfs_rq;
384 	unsigned long		shares;
385 
386 	/* A positive value indicates that this is a SCHED_IDLE group. */
387 	int			idle;
388 
389 #ifdef	CONFIG_SMP
390 	/*
391 	 * load_avg can be heavily contended at clock tick time, so put
392 	 * it in its own cacheline separated from the fields above which
393 	 * will also be accessed at each tick.
394 	 */
395 	atomic_long_t		load_avg ____cacheline_aligned;
396 #endif
397 #endif
398 
399 #ifdef CONFIG_RT_GROUP_SCHED
400 	struct sched_rt_entity	**rt_se;
401 	struct rt_rq		**rt_rq;
402 
403 	struct rt_bandwidth	rt_bandwidth;
404 #endif
405 
406 	struct rcu_head		rcu;
407 	struct list_head	list;
408 
409 	struct task_group	*parent;
410 	struct list_head	siblings;
411 	struct list_head	children;
412 
413 #ifdef CONFIG_SCHED_AUTOGROUP
414 	struct autogroup	*autogroup;
415 #endif
416 
417 	struct cfs_bandwidth	cfs_bandwidth;
418 
419 #ifdef CONFIG_UCLAMP_TASK_GROUP
420 	/* The two decimal precision [%] value requested from user-space */
421 	unsigned int		uclamp_pct[UCLAMP_CNT];
422 	/* Clamp values requested for a task group */
423 	struct uclamp_se	uclamp_req[UCLAMP_CNT];
424 	/* Effective clamp values used for a task group */
425 	struct uclamp_se	uclamp[UCLAMP_CNT];
426 #endif
427 
428 };
429 
430 #ifdef CONFIG_FAIR_GROUP_SCHED
431 #define ROOT_TASK_GROUP_LOAD	NICE_0_LOAD
432 
433 /*
434  * A weight of 0 or 1 can cause arithmetics problems.
435  * A weight of a cfs_rq is the sum of weights of which entities
436  * are queued on this cfs_rq, so a weight of a entity should not be
437  * too large, so as the shares value of a task group.
438  * (The default weight is 1024 - so there's no practical
439  *  limitation from this.)
440  */
441 #define MIN_SHARES		(1UL <<  1)
442 #define MAX_SHARES		(1UL << 18)
443 #endif
444 
445 typedef int (*tg_visitor)(struct task_group *, void *);
446 
447 extern int walk_tg_tree_from(struct task_group *from,
448 			     tg_visitor down, tg_visitor up, void *data);
449 
450 /*
451  * Iterate the full tree, calling @down when first entering a node and @up when
452  * leaving it for the final time.
453  *
454  * Caller must hold rcu_lock or sufficient equivalent.
455  */
456 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
457 {
458 	return walk_tg_tree_from(&root_task_group, down, up, data);
459 }
460 
461 extern int tg_nop(struct task_group *tg, void *data);
462 
463 extern void free_fair_sched_group(struct task_group *tg);
464 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
465 extern void online_fair_sched_group(struct task_group *tg);
466 extern void unregister_fair_sched_group(struct task_group *tg);
467 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
468 			struct sched_entity *se, int cpu,
469 			struct sched_entity *parent);
470 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
471 
472 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
473 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
474 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
475 
476 extern void unregister_rt_sched_group(struct task_group *tg);
477 extern void free_rt_sched_group(struct task_group *tg);
478 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
479 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
480 		struct sched_rt_entity *rt_se, int cpu,
481 		struct sched_rt_entity *parent);
482 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
483 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
484 extern long sched_group_rt_runtime(struct task_group *tg);
485 extern long sched_group_rt_period(struct task_group *tg);
486 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
487 
488 extern struct task_group *sched_create_group(struct task_group *parent);
489 extern void sched_online_group(struct task_group *tg,
490 			       struct task_group *parent);
491 extern void sched_destroy_group(struct task_group *tg);
492 extern void sched_release_group(struct task_group *tg);
493 
494 extern void sched_move_task(struct task_struct *tsk);
495 
496 #ifdef CONFIG_FAIR_GROUP_SCHED
497 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
498 
499 extern int sched_group_set_idle(struct task_group *tg, long idle);
500 
501 #ifdef CONFIG_SMP
502 extern void set_task_rq_fair(struct sched_entity *se,
503 			     struct cfs_rq *prev, struct cfs_rq *next);
504 #else /* !CONFIG_SMP */
505 static inline void set_task_rq_fair(struct sched_entity *se,
506 			     struct cfs_rq *prev, struct cfs_rq *next) { }
507 #endif /* CONFIG_SMP */
508 #endif /* CONFIG_FAIR_GROUP_SCHED */
509 
510 #else /* CONFIG_CGROUP_SCHED */
511 
512 struct cfs_bandwidth { };
513 
514 #endif	/* CONFIG_CGROUP_SCHED */
515 
516 /* CFS-related fields in a runqueue */
517 struct cfs_rq {
518 	struct load_weight	load;
519 	unsigned int		nr_running;
520 	unsigned int		h_nr_running;      /* SCHED_{NORMAL,BATCH,IDLE} */
521 	unsigned int		idle_nr_running;   /* SCHED_IDLE */
522 	unsigned int		idle_h_nr_running; /* SCHED_IDLE */
523 
524 	u64			exec_clock;
525 	u64			min_vruntime;
526 #ifdef CONFIG_SCHED_CORE
527 	unsigned int		forceidle_seq;
528 	u64			min_vruntime_fi;
529 #endif
530 
531 #ifndef CONFIG_64BIT
532 	u64			min_vruntime_copy;
533 #endif
534 
535 	struct rb_root_cached	tasks_timeline;
536 
537 	/*
538 	 * 'curr' points to currently running entity on this cfs_rq.
539 	 * It is set to NULL otherwise (i.e when none are currently running).
540 	 */
541 	struct sched_entity	*curr;
542 	struct sched_entity	*next;
543 	struct sched_entity	*last;
544 	struct sched_entity	*skip;
545 
546 #ifdef	CONFIG_SCHED_DEBUG
547 	unsigned int		nr_spread_over;
548 #endif
549 
550 #ifdef CONFIG_SMP
551 	/*
552 	 * CFS load tracking
553 	 */
554 	struct sched_avg	avg;
555 #ifndef CONFIG_64BIT
556 	u64			load_last_update_time_copy;
557 #endif
558 	struct {
559 		raw_spinlock_t	lock ____cacheline_aligned;
560 		int		nr;
561 		unsigned long	load_avg;
562 		unsigned long	util_avg;
563 		unsigned long	runnable_avg;
564 	} removed;
565 
566 #ifdef CONFIG_FAIR_GROUP_SCHED
567 	unsigned long		tg_load_avg_contrib;
568 	long			propagate;
569 	long			prop_runnable_sum;
570 
571 	/*
572 	 *   h_load = weight * f(tg)
573 	 *
574 	 * Where f(tg) is the recursive weight fraction assigned to
575 	 * this group.
576 	 */
577 	unsigned long		h_load;
578 	u64			last_h_load_update;
579 	struct sched_entity	*h_load_next;
580 #endif /* CONFIG_FAIR_GROUP_SCHED */
581 #endif /* CONFIG_SMP */
582 
583 #ifdef CONFIG_FAIR_GROUP_SCHED
584 	struct rq		*rq;	/* CPU runqueue to which this cfs_rq is attached */
585 
586 	/*
587 	 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
588 	 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
589 	 * (like users, containers etc.)
590 	 *
591 	 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
592 	 * This list is used during load balance.
593 	 */
594 	int			on_list;
595 	struct list_head	leaf_cfs_rq_list;
596 	struct task_group	*tg;	/* group that "owns" this runqueue */
597 
598 	/* Locally cached copy of our task_group's idle value */
599 	int			idle;
600 
601 #ifdef CONFIG_CFS_BANDWIDTH
602 	int			runtime_enabled;
603 	s64			runtime_remaining;
604 
605 	u64			throttled_clock;
606 	u64			throttled_clock_task;
607 	u64			throttled_clock_task_time;
608 	int			throttled;
609 	int			throttle_count;
610 	struct list_head	throttled_list;
611 #endif /* CONFIG_CFS_BANDWIDTH */
612 #endif /* CONFIG_FAIR_GROUP_SCHED */
613 };
614 
615 static inline int rt_bandwidth_enabled(void)
616 {
617 	return sysctl_sched_rt_runtime >= 0;
618 }
619 
620 /* RT IPI pull logic requires IRQ_WORK */
621 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
622 # define HAVE_RT_PUSH_IPI
623 #endif
624 
625 /* Real-Time classes' related field in a runqueue: */
626 struct rt_rq {
627 	struct rt_prio_array	active;
628 	unsigned int		rt_nr_running;
629 	unsigned int		rr_nr_running;
630 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
631 	struct {
632 		int		curr; /* highest queued rt task prio */
633 #ifdef CONFIG_SMP
634 		int		next; /* next highest */
635 #endif
636 	} highest_prio;
637 #endif
638 #ifdef CONFIG_SMP
639 	unsigned int		rt_nr_migratory;
640 	unsigned int		rt_nr_total;
641 	int			overloaded;
642 	struct plist_head	pushable_tasks;
643 
644 #endif /* CONFIG_SMP */
645 	int			rt_queued;
646 
647 	int			rt_throttled;
648 	u64			rt_time;
649 	u64			rt_runtime;
650 	/* Nests inside the rq lock: */
651 	raw_spinlock_t		rt_runtime_lock;
652 
653 #ifdef CONFIG_RT_GROUP_SCHED
654 	unsigned int		rt_nr_boosted;
655 
656 	struct rq		*rq;
657 	struct task_group	*tg;
658 #endif
659 };
660 
661 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
662 {
663 	return rt_rq->rt_queued && rt_rq->rt_nr_running;
664 }
665 
666 /* Deadline class' related fields in a runqueue */
667 struct dl_rq {
668 	/* runqueue is an rbtree, ordered by deadline */
669 	struct rb_root_cached	root;
670 
671 	unsigned int		dl_nr_running;
672 
673 #ifdef CONFIG_SMP
674 	/*
675 	 * Deadline values of the currently executing and the
676 	 * earliest ready task on this rq. Caching these facilitates
677 	 * the decision whether or not a ready but not running task
678 	 * should migrate somewhere else.
679 	 */
680 	struct {
681 		u64		curr;
682 		u64		next;
683 	} earliest_dl;
684 
685 	unsigned int		dl_nr_migratory;
686 	int			overloaded;
687 
688 	/*
689 	 * Tasks on this rq that can be pushed away. They are kept in
690 	 * an rb-tree, ordered by tasks' deadlines, with caching
691 	 * of the leftmost (earliest deadline) element.
692 	 */
693 	struct rb_root_cached	pushable_dl_tasks_root;
694 #else
695 	struct dl_bw		dl_bw;
696 #endif
697 	/*
698 	 * "Active utilization" for this runqueue: increased when a
699 	 * task wakes up (becomes TASK_RUNNING) and decreased when a
700 	 * task blocks
701 	 */
702 	u64			running_bw;
703 
704 	/*
705 	 * Utilization of the tasks "assigned" to this runqueue (including
706 	 * the tasks that are in runqueue and the tasks that executed on this
707 	 * CPU and blocked). Increased when a task moves to this runqueue, and
708 	 * decreased when the task moves away (migrates, changes scheduling
709 	 * policy, or terminates).
710 	 * This is needed to compute the "inactive utilization" for the
711 	 * runqueue (inactive utilization = this_bw - running_bw).
712 	 */
713 	u64			this_bw;
714 	u64			extra_bw;
715 
716 	/*
717 	 * Inverse of the fraction of CPU utilization that can be reclaimed
718 	 * by the GRUB algorithm.
719 	 */
720 	u64			bw_ratio;
721 };
722 
723 #ifdef CONFIG_FAIR_GROUP_SCHED
724 /* An entity is a task if it doesn't "own" a runqueue */
725 #define entity_is_task(se)	(!se->my_q)
726 
727 static inline void se_update_runnable(struct sched_entity *se)
728 {
729 	if (!entity_is_task(se))
730 		se->runnable_weight = se->my_q->h_nr_running;
731 }
732 
733 static inline long se_runnable(struct sched_entity *se)
734 {
735 	if (entity_is_task(se))
736 		return !!se->on_rq;
737 	else
738 		return se->runnable_weight;
739 }
740 
741 #else
742 #define entity_is_task(se)	1
743 
744 static inline void se_update_runnable(struct sched_entity *se) {}
745 
746 static inline long se_runnable(struct sched_entity *se)
747 {
748 	return !!se->on_rq;
749 }
750 #endif
751 
752 #ifdef CONFIG_SMP
753 /*
754  * XXX we want to get rid of these helpers and use the full load resolution.
755  */
756 static inline long se_weight(struct sched_entity *se)
757 {
758 	return scale_load_down(se->load.weight);
759 }
760 
761 
762 static inline bool sched_asym_prefer(int a, int b)
763 {
764 	return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
765 }
766 
767 struct perf_domain {
768 	struct em_perf_domain *em_pd;
769 	struct perf_domain *next;
770 	struct rcu_head rcu;
771 };
772 
773 /* Scheduling group status flags */
774 #define SG_OVERLOAD		0x1 /* More than one runnable task on a CPU. */
775 #define SG_OVERUTILIZED		0x2 /* One or more CPUs are over-utilized. */
776 
777 /*
778  * We add the notion of a root-domain which will be used to define per-domain
779  * variables. Each exclusive cpuset essentially defines an island domain by
780  * fully partitioning the member CPUs from any other cpuset. Whenever a new
781  * exclusive cpuset is created, we also create and attach a new root-domain
782  * object.
783  *
784  */
785 struct root_domain {
786 	atomic_t		refcount;
787 	atomic_t		rto_count;
788 	struct rcu_head		rcu;
789 	cpumask_var_t		span;
790 	cpumask_var_t		online;
791 
792 	/*
793 	 * Indicate pullable load on at least one CPU, e.g:
794 	 * - More than one runnable task
795 	 * - Running task is misfit
796 	 */
797 	int			overload;
798 
799 	/* Indicate one or more cpus over-utilized (tipping point) */
800 	int			overutilized;
801 
802 	/*
803 	 * The bit corresponding to a CPU gets set here if such CPU has more
804 	 * than one runnable -deadline task (as it is below for RT tasks).
805 	 */
806 	cpumask_var_t		dlo_mask;
807 	atomic_t		dlo_count;
808 	struct dl_bw		dl_bw;
809 	struct cpudl		cpudl;
810 
811 	/*
812 	 * Indicate whether a root_domain's dl_bw has been checked or
813 	 * updated. It's monotonously increasing value.
814 	 *
815 	 * Also, some corner cases, like 'wrap around' is dangerous, but given
816 	 * that u64 is 'big enough'. So that shouldn't be a concern.
817 	 */
818 	u64 visit_gen;
819 
820 #ifdef HAVE_RT_PUSH_IPI
821 	/*
822 	 * For IPI pull requests, loop across the rto_mask.
823 	 */
824 	struct irq_work		rto_push_work;
825 	raw_spinlock_t		rto_lock;
826 	/* These are only updated and read within rto_lock */
827 	int			rto_loop;
828 	int			rto_cpu;
829 	/* These atomics are updated outside of a lock */
830 	atomic_t		rto_loop_next;
831 	atomic_t		rto_loop_start;
832 #endif
833 	/*
834 	 * The "RT overload" flag: it gets set if a CPU has more than
835 	 * one runnable RT task.
836 	 */
837 	cpumask_var_t		rto_mask;
838 	struct cpupri		cpupri;
839 
840 	unsigned long		max_cpu_capacity;
841 
842 	/*
843 	 * NULL-terminated list of performance domains intersecting with the
844 	 * CPUs of the rd. Protected by RCU.
845 	 */
846 	struct perf_domain __rcu *pd;
847 };
848 
849 extern void init_defrootdomain(void);
850 extern int sched_init_domains(const struct cpumask *cpu_map);
851 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
852 extern void sched_get_rd(struct root_domain *rd);
853 extern void sched_put_rd(struct root_domain *rd);
854 
855 #ifdef HAVE_RT_PUSH_IPI
856 extern void rto_push_irq_work_func(struct irq_work *work);
857 #endif
858 #endif /* CONFIG_SMP */
859 
860 #ifdef CONFIG_UCLAMP_TASK
861 /*
862  * struct uclamp_bucket - Utilization clamp bucket
863  * @value: utilization clamp value for tasks on this clamp bucket
864  * @tasks: number of RUNNABLE tasks on this clamp bucket
865  *
866  * Keep track of how many tasks are RUNNABLE for a given utilization
867  * clamp value.
868  */
869 struct uclamp_bucket {
870 	unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
871 	unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
872 };
873 
874 /*
875  * struct uclamp_rq - rq's utilization clamp
876  * @value: currently active clamp values for a rq
877  * @bucket: utilization clamp buckets affecting a rq
878  *
879  * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
880  * A clamp value is affecting a rq when there is at least one task RUNNABLE
881  * (or actually running) with that value.
882  *
883  * There are up to UCLAMP_CNT possible different clamp values, currently there
884  * are only two: minimum utilization and maximum utilization.
885  *
886  * All utilization clamping values are MAX aggregated, since:
887  * - for util_min: we want to run the CPU at least at the max of the minimum
888  *   utilization required by its currently RUNNABLE tasks.
889  * - for util_max: we want to allow the CPU to run up to the max of the
890  *   maximum utilization allowed by its currently RUNNABLE tasks.
891  *
892  * Since on each system we expect only a limited number of different
893  * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
894  * the metrics required to compute all the per-rq utilization clamp values.
895  */
896 struct uclamp_rq {
897 	unsigned int value;
898 	struct uclamp_bucket bucket[UCLAMP_BUCKETS];
899 };
900 
901 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
902 #endif /* CONFIG_UCLAMP_TASK */
903 
904 /*
905  * This is the main, per-CPU runqueue data structure.
906  *
907  * Locking rule: those places that want to lock multiple runqueues
908  * (such as the load balancing or the thread migration code), lock
909  * acquire operations must be ordered by ascending &runqueue.
910  */
911 struct rq {
912 	/* runqueue lock: */
913 	raw_spinlock_t		__lock;
914 
915 	/*
916 	 * nr_running and cpu_load should be in the same cacheline because
917 	 * remote CPUs use both these fields when doing load calculation.
918 	 */
919 	unsigned int		nr_running;
920 #ifdef CONFIG_NUMA_BALANCING
921 	unsigned int		nr_numa_running;
922 	unsigned int		nr_preferred_running;
923 	unsigned int		numa_migrate_on;
924 #endif
925 #ifdef CONFIG_NO_HZ_COMMON
926 #ifdef CONFIG_SMP
927 	unsigned long		last_blocked_load_update_tick;
928 	unsigned int		has_blocked_load;
929 	call_single_data_t	nohz_csd;
930 #endif /* CONFIG_SMP */
931 	unsigned int		nohz_tick_stopped;
932 	atomic_t		nohz_flags;
933 #endif /* CONFIG_NO_HZ_COMMON */
934 
935 #ifdef CONFIG_SMP
936 	unsigned int		ttwu_pending;
937 #endif
938 	u64			nr_switches;
939 
940 #ifdef CONFIG_UCLAMP_TASK
941 	/* Utilization clamp values based on CPU's RUNNABLE tasks */
942 	struct uclamp_rq	uclamp[UCLAMP_CNT] ____cacheline_aligned;
943 	unsigned int		uclamp_flags;
944 #define UCLAMP_FLAG_IDLE 0x01
945 #endif
946 
947 	struct cfs_rq		cfs;
948 	struct rt_rq		rt;
949 	struct dl_rq		dl;
950 
951 #ifdef CONFIG_FAIR_GROUP_SCHED
952 	/* list of leaf cfs_rq on this CPU: */
953 	struct list_head	leaf_cfs_rq_list;
954 	struct list_head	*tmp_alone_branch;
955 #endif /* CONFIG_FAIR_GROUP_SCHED */
956 
957 	/*
958 	 * This is part of a global counter where only the total sum
959 	 * over all CPUs matters. A task can increase this counter on
960 	 * one CPU and if it got migrated afterwards it may decrease
961 	 * it on another CPU. Always updated under the runqueue lock:
962 	 */
963 	unsigned int		nr_uninterruptible;
964 
965 	struct task_struct __rcu	*curr;
966 	struct task_struct	*idle;
967 	struct task_struct	*stop;
968 	unsigned long		next_balance;
969 	struct mm_struct	*prev_mm;
970 
971 	unsigned int		clock_update_flags;
972 	u64			clock;
973 	/* Ensure that all clocks are in the same cache line */
974 	u64			clock_task ____cacheline_aligned;
975 	u64			clock_pelt;
976 	unsigned long		lost_idle_time;
977 
978 	atomic_t		nr_iowait;
979 
980 #ifdef CONFIG_SCHED_DEBUG
981 	u64 last_seen_need_resched_ns;
982 	int ticks_without_resched;
983 #endif
984 
985 #ifdef CONFIG_MEMBARRIER
986 	int membarrier_state;
987 #endif
988 
989 #ifdef CONFIG_SMP
990 	struct root_domain		*rd;
991 	struct sched_domain __rcu	*sd;
992 
993 	unsigned long		cpu_capacity;
994 	unsigned long		cpu_capacity_orig;
995 
996 	struct callback_head	*balance_callback;
997 
998 	unsigned char		nohz_idle_balance;
999 	unsigned char		idle_balance;
1000 
1001 	unsigned long		misfit_task_load;
1002 
1003 	/* For active balancing */
1004 	int			active_balance;
1005 	int			push_cpu;
1006 	struct cpu_stop_work	active_balance_work;
1007 
1008 	/* CPU of this runqueue: */
1009 	int			cpu;
1010 	int			online;
1011 
1012 	struct list_head cfs_tasks;
1013 
1014 	struct sched_avg	avg_rt;
1015 	struct sched_avg	avg_dl;
1016 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1017 	struct sched_avg	avg_irq;
1018 #endif
1019 #ifdef CONFIG_SCHED_THERMAL_PRESSURE
1020 	struct sched_avg	avg_thermal;
1021 #endif
1022 	u64			idle_stamp;
1023 	u64			avg_idle;
1024 
1025 	unsigned long		wake_stamp;
1026 	u64			wake_avg_idle;
1027 
1028 	/* This is used to determine avg_idle's max value */
1029 	u64			max_idle_balance_cost;
1030 
1031 #ifdef CONFIG_HOTPLUG_CPU
1032 	struct rcuwait		hotplug_wait;
1033 #endif
1034 #endif /* CONFIG_SMP */
1035 
1036 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1037 	u64			prev_irq_time;
1038 #endif
1039 #ifdef CONFIG_PARAVIRT
1040 	u64			prev_steal_time;
1041 #endif
1042 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1043 	u64			prev_steal_time_rq;
1044 #endif
1045 
1046 	/* calc_load related fields */
1047 	unsigned long		calc_load_update;
1048 	long			calc_load_active;
1049 
1050 #ifdef CONFIG_SCHED_HRTICK
1051 #ifdef CONFIG_SMP
1052 	call_single_data_t	hrtick_csd;
1053 #endif
1054 	struct hrtimer		hrtick_timer;
1055 	ktime_t 		hrtick_time;
1056 #endif
1057 
1058 #ifdef CONFIG_SCHEDSTATS
1059 	/* latency stats */
1060 	struct sched_info	rq_sched_info;
1061 	unsigned long long	rq_cpu_time;
1062 	/* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
1063 
1064 	/* sys_sched_yield() stats */
1065 	unsigned int		yld_count;
1066 
1067 	/* schedule() stats */
1068 	unsigned int		sched_count;
1069 	unsigned int		sched_goidle;
1070 
1071 	/* try_to_wake_up() stats */
1072 	unsigned int		ttwu_count;
1073 	unsigned int		ttwu_local;
1074 #endif
1075 
1076 #ifdef CONFIG_CPU_IDLE
1077 	/* Must be inspected within a rcu lock section */
1078 	struct cpuidle_state	*idle_state;
1079 #endif
1080 
1081 #ifdef CONFIG_SMP
1082 	unsigned int		nr_pinned;
1083 #endif
1084 	unsigned int		push_busy;
1085 	struct cpu_stop_work	push_work;
1086 
1087 #ifdef CONFIG_SCHED_CORE
1088 	/* per rq */
1089 	struct rq		*core;
1090 	struct task_struct	*core_pick;
1091 	unsigned int		core_enabled;
1092 	unsigned int		core_sched_seq;
1093 	struct rb_root		core_tree;
1094 
1095 	/* shared state -- careful with sched_core_cpu_deactivate() */
1096 	unsigned int		core_task_seq;
1097 	unsigned int		core_pick_seq;
1098 	unsigned long		core_cookie;
1099 	unsigned int		core_forceidle_count;
1100 	unsigned int		core_forceidle_seq;
1101 	unsigned int		core_forceidle_occupation;
1102 	u64			core_forceidle_start;
1103 #endif
1104 };
1105 
1106 #ifdef CONFIG_FAIR_GROUP_SCHED
1107 
1108 /* CPU runqueue to which this cfs_rq is attached */
1109 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1110 {
1111 	return cfs_rq->rq;
1112 }
1113 
1114 #else
1115 
1116 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1117 {
1118 	return container_of(cfs_rq, struct rq, cfs);
1119 }
1120 #endif
1121 
1122 static inline int cpu_of(struct rq *rq)
1123 {
1124 #ifdef CONFIG_SMP
1125 	return rq->cpu;
1126 #else
1127 	return 0;
1128 #endif
1129 }
1130 
1131 #define MDF_PUSH	0x01
1132 
1133 static inline bool is_migration_disabled(struct task_struct *p)
1134 {
1135 #ifdef CONFIG_SMP
1136 	return p->migration_disabled;
1137 #else
1138 	return false;
1139 #endif
1140 }
1141 
1142 struct sched_group;
1143 #ifdef CONFIG_SCHED_CORE
1144 static inline struct cpumask *sched_group_span(struct sched_group *sg);
1145 
1146 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled);
1147 
1148 static inline bool sched_core_enabled(struct rq *rq)
1149 {
1150 	return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled;
1151 }
1152 
1153 static inline bool sched_core_disabled(void)
1154 {
1155 	return !static_branch_unlikely(&__sched_core_enabled);
1156 }
1157 
1158 /*
1159  * Be careful with this function; not for general use. The return value isn't
1160  * stable unless you actually hold a relevant rq->__lock.
1161  */
1162 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1163 {
1164 	if (sched_core_enabled(rq))
1165 		return &rq->core->__lock;
1166 
1167 	return &rq->__lock;
1168 }
1169 
1170 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1171 {
1172 	if (rq->core_enabled)
1173 		return &rq->core->__lock;
1174 
1175 	return &rq->__lock;
1176 }
1177 
1178 bool cfs_prio_less(struct task_struct *a, struct task_struct *b, bool fi);
1179 
1180 /*
1181  * Helpers to check if the CPU's core cookie matches with the task's cookie
1182  * when core scheduling is enabled.
1183  * A special case is that the task's cookie always matches with CPU's core
1184  * cookie if the CPU is in an idle core.
1185  */
1186 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1187 {
1188 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1189 	if (!sched_core_enabled(rq))
1190 		return true;
1191 
1192 	return rq->core->core_cookie == p->core_cookie;
1193 }
1194 
1195 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1196 {
1197 	bool idle_core = true;
1198 	int cpu;
1199 
1200 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1201 	if (!sched_core_enabled(rq))
1202 		return true;
1203 
1204 	for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) {
1205 		if (!available_idle_cpu(cpu)) {
1206 			idle_core = false;
1207 			break;
1208 		}
1209 	}
1210 
1211 	/*
1212 	 * A CPU in an idle core is always the best choice for tasks with
1213 	 * cookies.
1214 	 */
1215 	return idle_core || rq->core->core_cookie == p->core_cookie;
1216 }
1217 
1218 static inline bool sched_group_cookie_match(struct rq *rq,
1219 					    struct task_struct *p,
1220 					    struct sched_group *group)
1221 {
1222 	int cpu;
1223 
1224 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1225 	if (!sched_core_enabled(rq))
1226 		return true;
1227 
1228 	for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
1229 		if (sched_core_cookie_match(rq, p))
1230 			return true;
1231 	}
1232 	return false;
1233 }
1234 
1235 static inline bool sched_core_enqueued(struct task_struct *p)
1236 {
1237 	return !RB_EMPTY_NODE(&p->core_node);
1238 }
1239 
1240 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p);
1241 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags);
1242 
1243 extern void sched_core_get(void);
1244 extern void sched_core_put(void);
1245 
1246 #else /* !CONFIG_SCHED_CORE */
1247 
1248 static inline bool sched_core_enabled(struct rq *rq)
1249 {
1250 	return false;
1251 }
1252 
1253 static inline bool sched_core_disabled(void)
1254 {
1255 	return true;
1256 }
1257 
1258 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1259 {
1260 	return &rq->__lock;
1261 }
1262 
1263 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1264 {
1265 	return &rq->__lock;
1266 }
1267 
1268 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1269 {
1270 	return true;
1271 }
1272 
1273 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1274 {
1275 	return true;
1276 }
1277 
1278 static inline bool sched_group_cookie_match(struct rq *rq,
1279 					    struct task_struct *p,
1280 					    struct sched_group *group)
1281 {
1282 	return true;
1283 }
1284 #endif /* CONFIG_SCHED_CORE */
1285 
1286 static inline void lockdep_assert_rq_held(struct rq *rq)
1287 {
1288 	lockdep_assert_held(__rq_lockp(rq));
1289 }
1290 
1291 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass);
1292 extern bool raw_spin_rq_trylock(struct rq *rq);
1293 extern void raw_spin_rq_unlock(struct rq *rq);
1294 
1295 static inline void raw_spin_rq_lock(struct rq *rq)
1296 {
1297 	raw_spin_rq_lock_nested(rq, 0);
1298 }
1299 
1300 static inline void raw_spin_rq_lock_irq(struct rq *rq)
1301 {
1302 	local_irq_disable();
1303 	raw_spin_rq_lock(rq);
1304 }
1305 
1306 static inline void raw_spin_rq_unlock_irq(struct rq *rq)
1307 {
1308 	raw_spin_rq_unlock(rq);
1309 	local_irq_enable();
1310 }
1311 
1312 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq)
1313 {
1314 	unsigned long flags;
1315 	local_irq_save(flags);
1316 	raw_spin_rq_lock(rq);
1317 	return flags;
1318 }
1319 
1320 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags)
1321 {
1322 	raw_spin_rq_unlock(rq);
1323 	local_irq_restore(flags);
1324 }
1325 
1326 #define raw_spin_rq_lock_irqsave(rq, flags)	\
1327 do {						\
1328 	flags = _raw_spin_rq_lock_irqsave(rq);	\
1329 } while (0)
1330 
1331 #ifdef CONFIG_SCHED_SMT
1332 extern void __update_idle_core(struct rq *rq);
1333 
1334 static inline void update_idle_core(struct rq *rq)
1335 {
1336 	if (static_branch_unlikely(&sched_smt_present))
1337 		__update_idle_core(rq);
1338 }
1339 
1340 #else
1341 static inline void update_idle_core(struct rq *rq) { }
1342 #endif
1343 
1344 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1345 
1346 #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
1347 #define this_rq()		this_cpu_ptr(&runqueues)
1348 #define task_rq(p)		cpu_rq(task_cpu(p))
1349 #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
1350 #define raw_rq()		raw_cpu_ptr(&runqueues)
1351 
1352 #ifdef CONFIG_FAIR_GROUP_SCHED
1353 static inline struct task_struct *task_of(struct sched_entity *se)
1354 {
1355 	SCHED_WARN_ON(!entity_is_task(se));
1356 	return container_of(se, struct task_struct, se);
1357 }
1358 
1359 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1360 {
1361 	return p->se.cfs_rq;
1362 }
1363 
1364 /* runqueue on which this entity is (to be) queued */
1365 static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se)
1366 {
1367 	return se->cfs_rq;
1368 }
1369 
1370 /* runqueue "owned" by this group */
1371 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1372 {
1373 	return grp->my_q;
1374 }
1375 
1376 #else
1377 
1378 static inline struct task_struct *task_of(struct sched_entity *se)
1379 {
1380 	return container_of(se, struct task_struct, se);
1381 }
1382 
1383 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1384 {
1385 	return &task_rq(p)->cfs;
1386 }
1387 
1388 static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se)
1389 {
1390 	struct task_struct *p = task_of(se);
1391 	struct rq *rq = task_rq(p);
1392 
1393 	return &rq->cfs;
1394 }
1395 
1396 /* runqueue "owned" by this group */
1397 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1398 {
1399 	return NULL;
1400 }
1401 #endif
1402 
1403 extern void update_rq_clock(struct rq *rq);
1404 
1405 /*
1406  * rq::clock_update_flags bits
1407  *
1408  * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1409  *  call to __schedule(). This is an optimisation to avoid
1410  *  neighbouring rq clock updates.
1411  *
1412  * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1413  *  in effect and calls to update_rq_clock() are being ignored.
1414  *
1415  * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1416  *  made to update_rq_clock() since the last time rq::lock was pinned.
1417  *
1418  * If inside of __schedule(), clock_update_flags will have been
1419  * shifted left (a left shift is a cheap operation for the fast path
1420  * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1421  *
1422  *	if (rq-clock_update_flags >= RQCF_UPDATED)
1423  *
1424  * to check if %RQCF_UPDATED is set. It'll never be shifted more than
1425  * one position though, because the next rq_unpin_lock() will shift it
1426  * back.
1427  */
1428 #define RQCF_REQ_SKIP		0x01
1429 #define RQCF_ACT_SKIP		0x02
1430 #define RQCF_UPDATED		0x04
1431 
1432 static inline void assert_clock_updated(struct rq *rq)
1433 {
1434 	/*
1435 	 * The only reason for not seeing a clock update since the
1436 	 * last rq_pin_lock() is if we're currently skipping updates.
1437 	 */
1438 	SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
1439 }
1440 
1441 static inline u64 rq_clock(struct rq *rq)
1442 {
1443 	lockdep_assert_rq_held(rq);
1444 	assert_clock_updated(rq);
1445 
1446 	return rq->clock;
1447 }
1448 
1449 static inline u64 rq_clock_task(struct rq *rq)
1450 {
1451 	lockdep_assert_rq_held(rq);
1452 	assert_clock_updated(rq);
1453 
1454 	return rq->clock_task;
1455 }
1456 
1457 /**
1458  * By default the decay is the default pelt decay period.
1459  * The decay shift can change the decay period in
1460  * multiples of 32.
1461  *  Decay shift		Decay period(ms)
1462  *	0			32
1463  *	1			64
1464  *	2			128
1465  *	3			256
1466  *	4			512
1467  */
1468 extern int sched_thermal_decay_shift;
1469 
1470 static inline u64 rq_clock_thermal(struct rq *rq)
1471 {
1472 	return rq_clock_task(rq) >> sched_thermal_decay_shift;
1473 }
1474 
1475 static inline void rq_clock_skip_update(struct rq *rq)
1476 {
1477 	lockdep_assert_rq_held(rq);
1478 	rq->clock_update_flags |= RQCF_REQ_SKIP;
1479 }
1480 
1481 /*
1482  * See rt task throttling, which is the only time a skip
1483  * request is canceled.
1484  */
1485 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1486 {
1487 	lockdep_assert_rq_held(rq);
1488 	rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1489 }
1490 
1491 struct rq_flags {
1492 	unsigned long flags;
1493 	struct pin_cookie cookie;
1494 #ifdef CONFIG_SCHED_DEBUG
1495 	/*
1496 	 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1497 	 * current pin context is stashed here in case it needs to be
1498 	 * restored in rq_repin_lock().
1499 	 */
1500 	unsigned int clock_update_flags;
1501 #endif
1502 };
1503 
1504 extern struct callback_head balance_push_callback;
1505 
1506 /*
1507  * Lockdep annotation that avoids accidental unlocks; it's like a
1508  * sticky/continuous lockdep_assert_held().
1509  *
1510  * This avoids code that has access to 'struct rq *rq' (basically everything in
1511  * the scheduler) from accidentally unlocking the rq if they do not also have a
1512  * copy of the (on-stack) 'struct rq_flags rf'.
1513  *
1514  * Also see Documentation/locking/lockdep-design.rst.
1515  */
1516 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1517 {
1518 	rf->cookie = lockdep_pin_lock(__rq_lockp(rq));
1519 
1520 #ifdef CONFIG_SCHED_DEBUG
1521 	rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1522 	rf->clock_update_flags = 0;
1523 #ifdef CONFIG_SMP
1524 	SCHED_WARN_ON(rq->balance_callback && rq->balance_callback != &balance_push_callback);
1525 #endif
1526 #endif
1527 }
1528 
1529 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1530 {
1531 #ifdef CONFIG_SCHED_DEBUG
1532 	if (rq->clock_update_flags > RQCF_ACT_SKIP)
1533 		rf->clock_update_flags = RQCF_UPDATED;
1534 #endif
1535 
1536 	lockdep_unpin_lock(__rq_lockp(rq), rf->cookie);
1537 }
1538 
1539 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1540 {
1541 	lockdep_repin_lock(__rq_lockp(rq), rf->cookie);
1542 
1543 #ifdef CONFIG_SCHED_DEBUG
1544 	/*
1545 	 * Restore the value we stashed in @rf for this pin context.
1546 	 */
1547 	rq->clock_update_flags |= rf->clock_update_flags;
1548 #endif
1549 }
1550 
1551 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1552 	__acquires(rq->lock);
1553 
1554 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1555 	__acquires(p->pi_lock)
1556 	__acquires(rq->lock);
1557 
1558 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1559 	__releases(rq->lock)
1560 {
1561 	rq_unpin_lock(rq, rf);
1562 	raw_spin_rq_unlock(rq);
1563 }
1564 
1565 static inline void
1566 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1567 	__releases(rq->lock)
1568 	__releases(p->pi_lock)
1569 {
1570 	rq_unpin_lock(rq, rf);
1571 	raw_spin_rq_unlock(rq);
1572 	raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1573 }
1574 
1575 static inline void
1576 rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1577 	__acquires(rq->lock)
1578 {
1579 	raw_spin_rq_lock_irqsave(rq, rf->flags);
1580 	rq_pin_lock(rq, rf);
1581 }
1582 
1583 static inline void
1584 rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1585 	__acquires(rq->lock)
1586 {
1587 	raw_spin_rq_lock_irq(rq);
1588 	rq_pin_lock(rq, rf);
1589 }
1590 
1591 static inline void
1592 rq_lock(struct rq *rq, struct rq_flags *rf)
1593 	__acquires(rq->lock)
1594 {
1595 	raw_spin_rq_lock(rq);
1596 	rq_pin_lock(rq, rf);
1597 }
1598 
1599 static inline void
1600 rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1601 	__releases(rq->lock)
1602 {
1603 	rq_unpin_lock(rq, rf);
1604 	raw_spin_rq_unlock_irqrestore(rq, rf->flags);
1605 }
1606 
1607 static inline void
1608 rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1609 	__releases(rq->lock)
1610 {
1611 	rq_unpin_lock(rq, rf);
1612 	raw_spin_rq_unlock_irq(rq);
1613 }
1614 
1615 static inline void
1616 rq_unlock(struct rq *rq, struct rq_flags *rf)
1617 	__releases(rq->lock)
1618 {
1619 	rq_unpin_lock(rq, rf);
1620 	raw_spin_rq_unlock(rq);
1621 }
1622 
1623 static inline struct rq *
1624 this_rq_lock_irq(struct rq_flags *rf)
1625 	__acquires(rq->lock)
1626 {
1627 	struct rq *rq;
1628 
1629 	local_irq_disable();
1630 	rq = this_rq();
1631 	rq_lock(rq, rf);
1632 	return rq;
1633 }
1634 
1635 #ifdef CONFIG_NUMA
1636 enum numa_topology_type {
1637 	NUMA_DIRECT,
1638 	NUMA_GLUELESS_MESH,
1639 	NUMA_BACKPLANE,
1640 };
1641 extern enum numa_topology_type sched_numa_topology_type;
1642 extern int sched_max_numa_distance;
1643 extern bool find_numa_distance(int distance);
1644 extern void sched_init_numa(int offline_node);
1645 extern void sched_update_numa(int cpu, bool online);
1646 extern void sched_domains_numa_masks_set(unsigned int cpu);
1647 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1648 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1649 #else
1650 static inline void sched_init_numa(int offline_node) { }
1651 static inline void sched_update_numa(int cpu, bool online) { }
1652 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
1653 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1654 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1655 {
1656 	return nr_cpu_ids;
1657 }
1658 #endif
1659 
1660 #ifdef CONFIG_NUMA_BALANCING
1661 /* The regions in numa_faults array from task_struct */
1662 enum numa_faults_stats {
1663 	NUMA_MEM = 0,
1664 	NUMA_CPU,
1665 	NUMA_MEMBUF,
1666 	NUMA_CPUBUF
1667 };
1668 extern void sched_setnuma(struct task_struct *p, int node);
1669 extern int migrate_task_to(struct task_struct *p, int cpu);
1670 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1671 			int cpu, int scpu);
1672 extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1673 #else
1674 static inline void
1675 init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1676 {
1677 }
1678 #endif /* CONFIG_NUMA_BALANCING */
1679 
1680 #ifdef CONFIG_SMP
1681 
1682 static inline void
1683 queue_balance_callback(struct rq *rq,
1684 		       struct callback_head *head,
1685 		       void (*func)(struct rq *rq))
1686 {
1687 	lockdep_assert_rq_held(rq);
1688 
1689 	if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
1690 		return;
1691 
1692 	head->func = (void (*)(struct callback_head *))func;
1693 	head->next = rq->balance_callback;
1694 	rq->balance_callback = head;
1695 }
1696 
1697 #define rcu_dereference_check_sched_domain(p) \
1698 	rcu_dereference_check((p), \
1699 			      lockdep_is_held(&sched_domains_mutex))
1700 
1701 /*
1702  * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1703  * See destroy_sched_domains: call_rcu for details.
1704  *
1705  * The domain tree of any CPU may only be accessed from within
1706  * preempt-disabled sections.
1707  */
1708 #define for_each_domain(cpu, __sd) \
1709 	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1710 			__sd; __sd = __sd->parent)
1711 
1712 /**
1713  * highest_flag_domain - Return highest sched_domain containing flag.
1714  * @cpu:	The CPU whose highest level of sched domain is to
1715  *		be returned.
1716  * @flag:	The flag to check for the highest sched_domain
1717  *		for the given CPU.
1718  *
1719  * Returns the highest sched_domain of a CPU which contains the given flag.
1720  */
1721 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1722 {
1723 	struct sched_domain *sd, *hsd = NULL;
1724 
1725 	for_each_domain(cpu, sd) {
1726 		if (!(sd->flags & flag))
1727 			break;
1728 		hsd = sd;
1729 	}
1730 
1731 	return hsd;
1732 }
1733 
1734 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1735 {
1736 	struct sched_domain *sd;
1737 
1738 	for_each_domain(cpu, sd) {
1739 		if (sd->flags & flag)
1740 			break;
1741 	}
1742 
1743 	return sd;
1744 }
1745 
1746 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
1747 DECLARE_PER_CPU(int, sd_llc_size);
1748 DECLARE_PER_CPU(int, sd_llc_id);
1749 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
1750 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
1751 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
1752 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
1753 extern struct static_key_false sched_asym_cpucapacity;
1754 
1755 struct sched_group_capacity {
1756 	atomic_t		ref;
1757 	/*
1758 	 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
1759 	 * for a single CPU.
1760 	 */
1761 	unsigned long		capacity;
1762 	unsigned long		min_capacity;		/* Min per-CPU capacity in group */
1763 	unsigned long		max_capacity;		/* Max per-CPU capacity in group */
1764 	unsigned long		next_update;
1765 	int			imbalance;		/* XXX unrelated to capacity but shared group state */
1766 
1767 #ifdef CONFIG_SCHED_DEBUG
1768 	int			id;
1769 #endif
1770 
1771 	unsigned long		cpumask[];		/* Balance mask */
1772 };
1773 
1774 struct sched_group {
1775 	struct sched_group	*next;			/* Must be a circular list */
1776 	atomic_t		ref;
1777 
1778 	unsigned int		group_weight;
1779 	struct sched_group_capacity *sgc;
1780 	int			asym_prefer_cpu;	/* CPU of highest priority in group */
1781 	int			flags;
1782 
1783 	/*
1784 	 * The CPUs this group covers.
1785 	 *
1786 	 * NOTE: this field is variable length. (Allocated dynamically
1787 	 * by attaching extra space to the end of the structure,
1788 	 * depending on how many CPUs the kernel has booted up with)
1789 	 */
1790 	unsigned long		cpumask[];
1791 };
1792 
1793 static inline struct cpumask *sched_group_span(struct sched_group *sg)
1794 {
1795 	return to_cpumask(sg->cpumask);
1796 }
1797 
1798 /*
1799  * See build_balance_mask().
1800  */
1801 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
1802 {
1803 	return to_cpumask(sg->sgc->cpumask);
1804 }
1805 
1806 /**
1807  * group_first_cpu - Returns the first CPU in the cpumask of a sched_group.
1808  * @group: The group whose first CPU is to be returned.
1809  */
1810 static inline unsigned int group_first_cpu(struct sched_group *group)
1811 {
1812 	return cpumask_first(sched_group_span(group));
1813 }
1814 
1815 extern int group_balance_cpu(struct sched_group *sg);
1816 
1817 #ifdef CONFIG_SCHED_DEBUG
1818 void update_sched_domain_debugfs(void);
1819 void dirty_sched_domain_sysctl(int cpu);
1820 #else
1821 static inline void update_sched_domain_debugfs(void)
1822 {
1823 }
1824 static inline void dirty_sched_domain_sysctl(int cpu)
1825 {
1826 }
1827 #endif
1828 
1829 extern int sched_update_scaling(void);
1830 
1831 extern void flush_smp_call_function_from_idle(void);
1832 
1833 #else /* !CONFIG_SMP: */
1834 static inline void flush_smp_call_function_from_idle(void) { }
1835 #endif
1836 
1837 #include "stats.h"
1838 
1839 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS)
1840 
1841 extern void __sched_core_account_forceidle(struct rq *rq);
1842 
1843 static inline void sched_core_account_forceidle(struct rq *rq)
1844 {
1845 	if (schedstat_enabled())
1846 		__sched_core_account_forceidle(rq);
1847 }
1848 
1849 extern void __sched_core_tick(struct rq *rq);
1850 
1851 static inline void sched_core_tick(struct rq *rq)
1852 {
1853 	if (sched_core_enabled(rq) && schedstat_enabled())
1854 		__sched_core_tick(rq);
1855 }
1856 
1857 #else
1858 
1859 static inline void sched_core_account_forceidle(struct rq *rq) {}
1860 
1861 static inline void sched_core_tick(struct rq *rq) {}
1862 
1863 #endif /* CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS */
1864 
1865 #ifdef CONFIG_CGROUP_SCHED
1866 
1867 /*
1868  * Return the group to which this tasks belongs.
1869  *
1870  * We cannot use task_css() and friends because the cgroup subsystem
1871  * changes that value before the cgroup_subsys::attach() method is called,
1872  * therefore we cannot pin it and might observe the wrong value.
1873  *
1874  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
1875  * core changes this before calling sched_move_task().
1876  *
1877  * Instead we use a 'copy' which is updated from sched_move_task() while
1878  * holding both task_struct::pi_lock and rq::lock.
1879  */
1880 static inline struct task_group *task_group(struct task_struct *p)
1881 {
1882 	return p->sched_task_group;
1883 }
1884 
1885 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
1886 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
1887 {
1888 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
1889 	struct task_group *tg = task_group(p);
1890 #endif
1891 
1892 #ifdef CONFIG_FAIR_GROUP_SCHED
1893 	set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
1894 	p->se.cfs_rq = tg->cfs_rq[cpu];
1895 	p->se.parent = tg->se[cpu];
1896 #endif
1897 
1898 #ifdef CONFIG_RT_GROUP_SCHED
1899 	p->rt.rt_rq  = tg->rt_rq[cpu];
1900 	p->rt.parent = tg->rt_se[cpu];
1901 #endif
1902 }
1903 
1904 #else /* CONFIG_CGROUP_SCHED */
1905 
1906 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
1907 static inline struct task_group *task_group(struct task_struct *p)
1908 {
1909 	return NULL;
1910 }
1911 
1912 #endif /* CONFIG_CGROUP_SCHED */
1913 
1914 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
1915 {
1916 	set_task_rq(p, cpu);
1917 #ifdef CONFIG_SMP
1918 	/*
1919 	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
1920 	 * successfully executed on another CPU. We must ensure that updates of
1921 	 * per-task data have been completed by this moment.
1922 	 */
1923 	smp_wmb();
1924 	WRITE_ONCE(task_thread_info(p)->cpu, cpu);
1925 	p->wake_cpu = cpu;
1926 #endif
1927 }
1928 
1929 /*
1930  * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
1931  */
1932 #ifdef CONFIG_SCHED_DEBUG
1933 # define const_debug __read_mostly
1934 #else
1935 # define const_debug const
1936 #endif
1937 
1938 #define SCHED_FEAT(name, enabled)	\
1939 	__SCHED_FEAT_##name ,
1940 
1941 enum {
1942 #include "features.h"
1943 	__SCHED_FEAT_NR,
1944 };
1945 
1946 #undef SCHED_FEAT
1947 
1948 #ifdef CONFIG_SCHED_DEBUG
1949 
1950 /*
1951  * To support run-time toggling of sched features, all the translation units
1952  * (but core.c) reference the sysctl_sched_features defined in core.c.
1953  */
1954 extern const_debug unsigned int sysctl_sched_features;
1955 
1956 #ifdef CONFIG_JUMP_LABEL
1957 #define SCHED_FEAT(name, enabled)					\
1958 static __always_inline bool static_branch_##name(struct static_key *key) \
1959 {									\
1960 	return static_key_##enabled(key);				\
1961 }
1962 
1963 #include "features.h"
1964 #undef SCHED_FEAT
1965 
1966 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
1967 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
1968 
1969 #else /* !CONFIG_JUMP_LABEL */
1970 
1971 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1972 
1973 #endif /* CONFIG_JUMP_LABEL */
1974 
1975 #else /* !SCHED_DEBUG */
1976 
1977 /*
1978  * Each translation unit has its own copy of sysctl_sched_features to allow
1979  * constants propagation at compile time and compiler optimization based on
1980  * features default.
1981  */
1982 #define SCHED_FEAT(name, enabled)	\
1983 	(1UL << __SCHED_FEAT_##name) * enabled |
1984 static const_debug __maybe_unused unsigned int sysctl_sched_features =
1985 #include "features.h"
1986 	0;
1987 #undef SCHED_FEAT
1988 
1989 #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1990 
1991 #endif /* SCHED_DEBUG */
1992 
1993 extern struct static_key_false sched_numa_balancing;
1994 extern struct static_key_false sched_schedstats;
1995 
1996 static inline u64 global_rt_period(void)
1997 {
1998 	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
1999 }
2000 
2001 static inline u64 global_rt_runtime(void)
2002 {
2003 	if (sysctl_sched_rt_runtime < 0)
2004 		return RUNTIME_INF;
2005 
2006 	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
2007 }
2008 
2009 static inline int task_current(struct rq *rq, struct task_struct *p)
2010 {
2011 	return rq->curr == p;
2012 }
2013 
2014 static inline int task_running(struct rq *rq, struct task_struct *p)
2015 {
2016 #ifdef CONFIG_SMP
2017 	return p->on_cpu;
2018 #else
2019 	return task_current(rq, p);
2020 #endif
2021 }
2022 
2023 static inline int task_on_rq_queued(struct task_struct *p)
2024 {
2025 	return p->on_rq == TASK_ON_RQ_QUEUED;
2026 }
2027 
2028 static inline int task_on_rq_migrating(struct task_struct *p)
2029 {
2030 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
2031 }
2032 
2033 /* Wake flags. The first three directly map to some SD flag value */
2034 #define WF_EXEC     0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
2035 #define WF_FORK     0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
2036 #define WF_TTWU     0x08 /* Wakeup;            maps to SD_BALANCE_WAKE */
2037 
2038 #define WF_SYNC     0x10 /* Waker goes to sleep after wakeup */
2039 #define WF_MIGRATED 0x20 /* Internal use, task got migrated */
2040 #define WF_ON_CPU   0x40 /* Wakee is on_cpu */
2041 
2042 #ifdef CONFIG_SMP
2043 static_assert(WF_EXEC == SD_BALANCE_EXEC);
2044 static_assert(WF_FORK == SD_BALANCE_FORK);
2045 static_assert(WF_TTWU == SD_BALANCE_WAKE);
2046 #endif
2047 
2048 /*
2049  * To aid in avoiding the subversion of "niceness" due to uneven distribution
2050  * of tasks with abnormal "nice" values across CPUs the contribution that
2051  * each task makes to its run queue's load is weighted according to its
2052  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
2053  * scaled version of the new time slice allocation that they receive on time
2054  * slice expiry etc.
2055  */
2056 
2057 #define WEIGHT_IDLEPRIO		3
2058 #define WMULT_IDLEPRIO		1431655765
2059 
2060 extern const int		sched_prio_to_weight[40];
2061 extern const u32		sched_prio_to_wmult[40];
2062 
2063 /*
2064  * {de,en}queue flags:
2065  *
2066  * DEQUEUE_SLEEP  - task is no longer runnable
2067  * ENQUEUE_WAKEUP - task just became runnable
2068  *
2069  * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
2070  *                are in a known state which allows modification. Such pairs
2071  *                should preserve as much state as possible.
2072  *
2073  * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
2074  *        in the runqueue.
2075  *
2076  * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
2077  * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
2078  * ENQUEUE_MIGRATED  - the task was migrated during wakeup
2079  *
2080  */
2081 
2082 #define DEQUEUE_SLEEP		0x01
2083 #define DEQUEUE_SAVE		0x02 /* Matches ENQUEUE_RESTORE */
2084 #define DEQUEUE_MOVE		0x04 /* Matches ENQUEUE_MOVE */
2085 #define DEQUEUE_NOCLOCK		0x08 /* Matches ENQUEUE_NOCLOCK */
2086 
2087 #define ENQUEUE_WAKEUP		0x01
2088 #define ENQUEUE_RESTORE		0x02
2089 #define ENQUEUE_MOVE		0x04
2090 #define ENQUEUE_NOCLOCK		0x08
2091 
2092 #define ENQUEUE_HEAD		0x10
2093 #define ENQUEUE_REPLENISH	0x20
2094 #ifdef CONFIG_SMP
2095 #define ENQUEUE_MIGRATED	0x40
2096 #else
2097 #define ENQUEUE_MIGRATED	0x00
2098 #endif
2099 
2100 #define RETRY_TASK		((void *)-1UL)
2101 
2102 struct sched_class {
2103 
2104 #ifdef CONFIG_UCLAMP_TASK
2105 	int uclamp_enabled;
2106 #endif
2107 
2108 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
2109 	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
2110 	void (*yield_task)   (struct rq *rq);
2111 	bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
2112 
2113 	void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags);
2114 
2115 	struct task_struct *(*pick_next_task)(struct rq *rq);
2116 
2117 	void (*put_prev_task)(struct rq *rq, struct task_struct *p);
2118 	void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
2119 
2120 #ifdef CONFIG_SMP
2121 	int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2122 	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
2123 
2124 	struct task_struct * (*pick_task)(struct rq *rq);
2125 
2126 	void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
2127 
2128 	void (*task_woken)(struct rq *this_rq, struct task_struct *task);
2129 
2130 	void (*set_cpus_allowed)(struct task_struct *p,
2131 				 const struct cpumask *newmask,
2132 				 u32 flags);
2133 
2134 	void (*rq_online)(struct rq *rq);
2135 	void (*rq_offline)(struct rq *rq);
2136 
2137 	struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
2138 #endif
2139 
2140 	void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
2141 	void (*task_fork)(struct task_struct *p);
2142 	void (*task_dead)(struct task_struct *p);
2143 
2144 	/*
2145 	 * The switched_from() call is allowed to drop rq->lock, therefore we
2146 	 * cannot assume the switched_from/switched_to pair is serialized by
2147 	 * rq->lock. They are however serialized by p->pi_lock.
2148 	 */
2149 	void (*switched_from)(struct rq *this_rq, struct task_struct *task);
2150 	void (*switched_to)  (struct rq *this_rq, struct task_struct *task);
2151 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
2152 			      int oldprio);
2153 
2154 	unsigned int (*get_rr_interval)(struct rq *rq,
2155 					struct task_struct *task);
2156 
2157 	void (*update_curr)(struct rq *rq);
2158 
2159 #define TASK_SET_GROUP		0
2160 #define TASK_MOVE_GROUP		1
2161 
2162 #ifdef CONFIG_FAIR_GROUP_SCHED
2163 	void (*task_change_group)(struct task_struct *p, int type);
2164 #endif
2165 };
2166 
2167 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
2168 {
2169 	WARN_ON_ONCE(rq->curr != prev);
2170 	prev->sched_class->put_prev_task(rq, prev);
2171 }
2172 
2173 static inline void set_next_task(struct rq *rq, struct task_struct *next)
2174 {
2175 	next->sched_class->set_next_task(rq, next, false);
2176 }
2177 
2178 
2179 /*
2180  * Helper to define a sched_class instance; each one is placed in a separate
2181  * section which is ordered by the linker script:
2182  *
2183  *   include/asm-generic/vmlinux.lds.h
2184  *
2185  * Also enforce alignment on the instance, not the type, to guarantee layout.
2186  */
2187 #define DEFINE_SCHED_CLASS(name) \
2188 const struct sched_class name##_sched_class \
2189 	__aligned(__alignof__(struct sched_class)) \
2190 	__section("__" #name "_sched_class")
2191 
2192 /* Defined in include/asm-generic/vmlinux.lds.h */
2193 extern struct sched_class __begin_sched_classes[];
2194 extern struct sched_class __end_sched_classes[];
2195 
2196 #define sched_class_highest (__end_sched_classes - 1)
2197 #define sched_class_lowest  (__begin_sched_classes - 1)
2198 
2199 #define for_class_range(class, _from, _to) \
2200 	for (class = (_from); class != (_to); class--)
2201 
2202 #define for_each_class(class) \
2203 	for_class_range(class, sched_class_highest, sched_class_lowest)
2204 
2205 extern const struct sched_class stop_sched_class;
2206 extern const struct sched_class dl_sched_class;
2207 extern const struct sched_class rt_sched_class;
2208 extern const struct sched_class fair_sched_class;
2209 extern const struct sched_class idle_sched_class;
2210 
2211 static inline bool sched_stop_runnable(struct rq *rq)
2212 {
2213 	return rq->stop && task_on_rq_queued(rq->stop);
2214 }
2215 
2216 static inline bool sched_dl_runnable(struct rq *rq)
2217 {
2218 	return rq->dl.dl_nr_running > 0;
2219 }
2220 
2221 static inline bool sched_rt_runnable(struct rq *rq)
2222 {
2223 	return rq->rt.rt_queued > 0;
2224 }
2225 
2226 static inline bool sched_fair_runnable(struct rq *rq)
2227 {
2228 	return rq->cfs.nr_running > 0;
2229 }
2230 
2231 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2232 extern struct task_struct *pick_next_task_idle(struct rq *rq);
2233 
2234 #define SCA_CHECK		0x01
2235 #define SCA_MIGRATE_DISABLE	0x02
2236 #define SCA_MIGRATE_ENABLE	0x04
2237 #define SCA_USER		0x08
2238 
2239 #ifdef CONFIG_SMP
2240 
2241 extern void update_group_capacity(struct sched_domain *sd, int cpu);
2242 
2243 extern void trigger_load_balance(struct rq *rq);
2244 
2245 extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask, u32 flags);
2246 
2247 static inline struct task_struct *get_push_task(struct rq *rq)
2248 {
2249 	struct task_struct *p = rq->curr;
2250 
2251 	lockdep_assert_rq_held(rq);
2252 
2253 	if (rq->push_busy)
2254 		return NULL;
2255 
2256 	if (p->nr_cpus_allowed == 1)
2257 		return NULL;
2258 
2259 	if (p->migration_disabled)
2260 		return NULL;
2261 
2262 	rq->push_busy = true;
2263 	return get_task_struct(p);
2264 }
2265 
2266 extern int push_cpu_stop(void *arg);
2267 
2268 #endif
2269 
2270 #ifdef CONFIG_CPU_IDLE
2271 static inline void idle_set_state(struct rq *rq,
2272 				  struct cpuidle_state *idle_state)
2273 {
2274 	rq->idle_state = idle_state;
2275 }
2276 
2277 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2278 {
2279 	SCHED_WARN_ON(!rcu_read_lock_held());
2280 
2281 	return rq->idle_state;
2282 }
2283 #else
2284 static inline void idle_set_state(struct rq *rq,
2285 				  struct cpuidle_state *idle_state)
2286 {
2287 }
2288 
2289 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2290 {
2291 	return NULL;
2292 }
2293 #endif
2294 
2295 extern void schedule_idle(void);
2296 
2297 extern void sysrq_sched_debug_show(void);
2298 extern void sched_init_granularity(void);
2299 extern void update_max_interval(void);
2300 
2301 extern void init_sched_dl_class(void);
2302 extern void init_sched_rt_class(void);
2303 extern void init_sched_fair_class(void);
2304 
2305 extern void reweight_task(struct task_struct *p, int prio);
2306 
2307 extern void resched_curr(struct rq *rq);
2308 extern void resched_cpu(int cpu);
2309 
2310 extern struct rt_bandwidth def_rt_bandwidth;
2311 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
2312 
2313 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
2314 extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
2315 extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se);
2316 
2317 #define BW_SHIFT		20
2318 #define BW_UNIT			(1 << BW_SHIFT)
2319 #define RATIO_SHIFT		8
2320 #define MAX_BW_BITS		(64 - BW_SHIFT)
2321 #define MAX_BW			((1ULL << MAX_BW_BITS) - 1)
2322 unsigned long to_ratio(u64 period, u64 runtime);
2323 
2324 extern void init_entity_runnable_average(struct sched_entity *se);
2325 extern void post_init_entity_util_avg(struct task_struct *p);
2326 
2327 #ifdef CONFIG_NO_HZ_FULL
2328 extern bool sched_can_stop_tick(struct rq *rq);
2329 extern int __init sched_tick_offload_init(void);
2330 
2331 /*
2332  * Tick may be needed by tasks in the runqueue depending on their policy and
2333  * requirements. If tick is needed, lets send the target an IPI to kick it out of
2334  * nohz mode if necessary.
2335  */
2336 static inline void sched_update_tick_dependency(struct rq *rq)
2337 {
2338 	int cpu = cpu_of(rq);
2339 
2340 	if (!tick_nohz_full_cpu(cpu))
2341 		return;
2342 
2343 	if (sched_can_stop_tick(rq))
2344 		tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
2345 	else
2346 		tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
2347 }
2348 #else
2349 static inline int sched_tick_offload_init(void) { return 0; }
2350 static inline void sched_update_tick_dependency(struct rq *rq) { }
2351 #endif
2352 
2353 static inline void add_nr_running(struct rq *rq, unsigned count)
2354 {
2355 	unsigned prev_nr = rq->nr_running;
2356 
2357 	rq->nr_running = prev_nr + count;
2358 	if (trace_sched_update_nr_running_tp_enabled()) {
2359 		call_trace_sched_update_nr_running(rq, count);
2360 	}
2361 
2362 #ifdef CONFIG_SMP
2363 	if (prev_nr < 2 && rq->nr_running >= 2) {
2364 		if (!READ_ONCE(rq->rd->overload))
2365 			WRITE_ONCE(rq->rd->overload, 1);
2366 	}
2367 #endif
2368 
2369 	sched_update_tick_dependency(rq);
2370 }
2371 
2372 static inline void sub_nr_running(struct rq *rq, unsigned count)
2373 {
2374 	rq->nr_running -= count;
2375 	if (trace_sched_update_nr_running_tp_enabled()) {
2376 		call_trace_sched_update_nr_running(rq, -count);
2377 	}
2378 
2379 	/* Check if we still need preemption */
2380 	sched_update_tick_dependency(rq);
2381 }
2382 
2383 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
2384 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
2385 
2386 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
2387 
2388 extern const_debug unsigned int sysctl_sched_nr_migrate;
2389 extern const_debug unsigned int sysctl_sched_migration_cost;
2390 
2391 #ifdef CONFIG_SCHED_DEBUG
2392 extern unsigned int sysctl_sched_latency;
2393 extern unsigned int sysctl_sched_min_granularity;
2394 extern unsigned int sysctl_sched_idle_min_granularity;
2395 extern unsigned int sysctl_sched_wakeup_granularity;
2396 extern int sysctl_resched_latency_warn_ms;
2397 extern int sysctl_resched_latency_warn_once;
2398 
2399 extern unsigned int sysctl_sched_tunable_scaling;
2400 
2401 extern unsigned int sysctl_numa_balancing_scan_delay;
2402 extern unsigned int sysctl_numa_balancing_scan_period_min;
2403 extern unsigned int sysctl_numa_balancing_scan_period_max;
2404 extern unsigned int sysctl_numa_balancing_scan_size;
2405 #endif
2406 
2407 #ifdef CONFIG_SCHED_HRTICK
2408 
2409 /*
2410  * Use hrtick when:
2411  *  - enabled by features
2412  *  - hrtimer is actually high res
2413  */
2414 static inline int hrtick_enabled(struct rq *rq)
2415 {
2416 	if (!cpu_active(cpu_of(rq)))
2417 		return 0;
2418 	return hrtimer_is_hres_active(&rq->hrtick_timer);
2419 }
2420 
2421 static inline int hrtick_enabled_fair(struct rq *rq)
2422 {
2423 	if (!sched_feat(HRTICK))
2424 		return 0;
2425 	return hrtick_enabled(rq);
2426 }
2427 
2428 static inline int hrtick_enabled_dl(struct rq *rq)
2429 {
2430 	if (!sched_feat(HRTICK_DL))
2431 		return 0;
2432 	return hrtick_enabled(rq);
2433 }
2434 
2435 void hrtick_start(struct rq *rq, u64 delay);
2436 
2437 #else
2438 
2439 static inline int hrtick_enabled_fair(struct rq *rq)
2440 {
2441 	return 0;
2442 }
2443 
2444 static inline int hrtick_enabled_dl(struct rq *rq)
2445 {
2446 	return 0;
2447 }
2448 
2449 static inline int hrtick_enabled(struct rq *rq)
2450 {
2451 	return 0;
2452 }
2453 
2454 #endif /* CONFIG_SCHED_HRTICK */
2455 
2456 #ifndef arch_scale_freq_tick
2457 static __always_inline
2458 void arch_scale_freq_tick(void)
2459 {
2460 }
2461 #endif
2462 
2463 #ifndef arch_scale_freq_capacity
2464 /**
2465  * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
2466  * @cpu: the CPU in question.
2467  *
2468  * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
2469  *
2470  *     f_curr
2471  *     ------ * SCHED_CAPACITY_SCALE
2472  *     f_max
2473  */
2474 static __always_inline
2475 unsigned long arch_scale_freq_capacity(int cpu)
2476 {
2477 	return SCHED_CAPACITY_SCALE;
2478 }
2479 #endif
2480 
2481 
2482 #ifdef CONFIG_SMP
2483 
2484 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2)
2485 {
2486 #ifdef CONFIG_SCHED_CORE
2487 	/*
2488 	 * In order to not have {0,2},{1,3} turn into into an AB-BA,
2489 	 * order by core-id first and cpu-id second.
2490 	 *
2491 	 * Notably:
2492 	 *
2493 	 *	double_rq_lock(0,3); will take core-0, core-1 lock
2494 	 *	double_rq_lock(1,2); will take core-1, core-0 lock
2495 	 *
2496 	 * when only cpu-id is considered.
2497 	 */
2498 	if (rq1->core->cpu < rq2->core->cpu)
2499 		return true;
2500 	if (rq1->core->cpu > rq2->core->cpu)
2501 		return false;
2502 
2503 	/*
2504 	 * __sched_core_flip() relies on SMT having cpu-id lock order.
2505 	 */
2506 #endif
2507 	return rq1->cpu < rq2->cpu;
2508 }
2509 
2510 extern void double_rq_lock(struct rq *rq1, struct rq *rq2);
2511 
2512 #ifdef CONFIG_PREEMPTION
2513 
2514 /*
2515  * fair double_lock_balance: Safely acquires both rq->locks in a fair
2516  * way at the expense of forcing extra atomic operations in all
2517  * invocations.  This assures that the double_lock is acquired using the
2518  * same underlying policy as the spinlock_t on this architecture, which
2519  * reduces latency compared to the unfair variant below.  However, it
2520  * also adds more overhead and therefore may reduce throughput.
2521  */
2522 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2523 	__releases(this_rq->lock)
2524 	__acquires(busiest->lock)
2525 	__acquires(this_rq->lock)
2526 {
2527 	raw_spin_rq_unlock(this_rq);
2528 	double_rq_lock(this_rq, busiest);
2529 
2530 	return 1;
2531 }
2532 
2533 #else
2534 /*
2535  * Unfair double_lock_balance: Optimizes throughput at the expense of
2536  * latency by eliminating extra atomic operations when the locks are
2537  * already in proper order on entry.  This favors lower CPU-ids and will
2538  * grant the double lock to lower CPUs over higher ids under contention,
2539  * regardless of entry order into the function.
2540  */
2541 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2542 	__releases(this_rq->lock)
2543 	__acquires(busiest->lock)
2544 	__acquires(this_rq->lock)
2545 {
2546 	if (__rq_lockp(this_rq) == __rq_lockp(busiest))
2547 		return 0;
2548 
2549 	if (likely(raw_spin_rq_trylock(busiest)))
2550 		return 0;
2551 
2552 	if (rq_order_less(this_rq, busiest)) {
2553 		raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING);
2554 		return 0;
2555 	}
2556 
2557 	raw_spin_rq_unlock(this_rq);
2558 	double_rq_lock(this_rq, busiest);
2559 
2560 	return 1;
2561 }
2562 
2563 #endif /* CONFIG_PREEMPTION */
2564 
2565 /*
2566  * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
2567  */
2568 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
2569 {
2570 	lockdep_assert_irqs_disabled();
2571 
2572 	return _double_lock_balance(this_rq, busiest);
2573 }
2574 
2575 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
2576 	__releases(busiest->lock)
2577 {
2578 	if (__rq_lockp(this_rq) != __rq_lockp(busiest))
2579 		raw_spin_rq_unlock(busiest);
2580 	lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_);
2581 }
2582 
2583 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
2584 {
2585 	if (l1 > l2)
2586 		swap(l1, l2);
2587 
2588 	spin_lock(l1);
2589 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2590 }
2591 
2592 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
2593 {
2594 	if (l1 > l2)
2595 		swap(l1, l2);
2596 
2597 	spin_lock_irq(l1);
2598 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2599 }
2600 
2601 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
2602 {
2603 	if (l1 > l2)
2604 		swap(l1, l2);
2605 
2606 	raw_spin_lock(l1);
2607 	raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2608 }
2609 
2610 /*
2611  * double_rq_unlock - safely unlock two runqueues
2612  *
2613  * Note this does not restore interrupts like task_rq_unlock,
2614  * you need to do so manually after calling.
2615  */
2616 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2617 	__releases(rq1->lock)
2618 	__releases(rq2->lock)
2619 {
2620 	if (__rq_lockp(rq1) != __rq_lockp(rq2))
2621 		raw_spin_rq_unlock(rq2);
2622 	else
2623 		__release(rq2->lock);
2624 	raw_spin_rq_unlock(rq1);
2625 }
2626 
2627 extern void set_rq_online (struct rq *rq);
2628 extern void set_rq_offline(struct rq *rq);
2629 extern bool sched_smp_initialized;
2630 
2631 #else /* CONFIG_SMP */
2632 
2633 /*
2634  * double_rq_lock - safely lock two runqueues
2635  *
2636  * Note this does not disable interrupts like task_rq_lock,
2637  * you need to do so manually before calling.
2638  */
2639 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2640 	__acquires(rq1->lock)
2641 	__acquires(rq2->lock)
2642 {
2643 	BUG_ON(!irqs_disabled());
2644 	BUG_ON(rq1 != rq2);
2645 	raw_spin_rq_lock(rq1);
2646 	__acquire(rq2->lock);	/* Fake it out ;) */
2647 }
2648 
2649 /*
2650  * double_rq_unlock - safely unlock two runqueues
2651  *
2652  * Note this does not restore interrupts like task_rq_unlock,
2653  * you need to do so manually after calling.
2654  */
2655 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2656 	__releases(rq1->lock)
2657 	__releases(rq2->lock)
2658 {
2659 	BUG_ON(rq1 != rq2);
2660 	raw_spin_rq_unlock(rq1);
2661 	__release(rq2->lock);
2662 }
2663 
2664 #endif
2665 
2666 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
2667 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
2668 
2669 #ifdef	CONFIG_SCHED_DEBUG
2670 extern bool sched_debug_verbose;
2671 
2672 extern void print_cfs_stats(struct seq_file *m, int cpu);
2673 extern void print_rt_stats(struct seq_file *m, int cpu);
2674 extern void print_dl_stats(struct seq_file *m, int cpu);
2675 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
2676 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
2677 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
2678 
2679 extern void resched_latency_warn(int cpu, u64 latency);
2680 #ifdef CONFIG_NUMA_BALANCING
2681 extern void
2682 show_numa_stats(struct task_struct *p, struct seq_file *m);
2683 extern void
2684 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
2685 	unsigned long tpf, unsigned long gsf, unsigned long gpf);
2686 #endif /* CONFIG_NUMA_BALANCING */
2687 #else
2688 static inline void resched_latency_warn(int cpu, u64 latency) {}
2689 #endif /* CONFIG_SCHED_DEBUG */
2690 
2691 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
2692 extern void init_rt_rq(struct rt_rq *rt_rq);
2693 extern void init_dl_rq(struct dl_rq *dl_rq);
2694 
2695 extern void cfs_bandwidth_usage_inc(void);
2696 extern void cfs_bandwidth_usage_dec(void);
2697 
2698 #ifdef CONFIG_NO_HZ_COMMON
2699 #define NOHZ_BALANCE_KICK_BIT	0
2700 #define NOHZ_STATS_KICK_BIT	1
2701 #define NOHZ_NEWILB_KICK_BIT	2
2702 #define NOHZ_NEXT_KICK_BIT	3
2703 
2704 /* Run rebalance_domains() */
2705 #define NOHZ_BALANCE_KICK	BIT(NOHZ_BALANCE_KICK_BIT)
2706 /* Update blocked load */
2707 #define NOHZ_STATS_KICK		BIT(NOHZ_STATS_KICK_BIT)
2708 /* Update blocked load when entering idle */
2709 #define NOHZ_NEWILB_KICK	BIT(NOHZ_NEWILB_KICK_BIT)
2710 /* Update nohz.next_balance */
2711 #define NOHZ_NEXT_KICK		BIT(NOHZ_NEXT_KICK_BIT)
2712 
2713 #define NOHZ_KICK_MASK	(NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK)
2714 
2715 #define nohz_flags(cpu)	(&cpu_rq(cpu)->nohz_flags)
2716 
2717 extern void nohz_balance_exit_idle(struct rq *rq);
2718 #else
2719 static inline void nohz_balance_exit_idle(struct rq *rq) { }
2720 #endif
2721 
2722 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
2723 extern void nohz_run_idle_balance(int cpu);
2724 #else
2725 static inline void nohz_run_idle_balance(int cpu) { }
2726 #endif
2727 
2728 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2729 struct irqtime {
2730 	u64			total;
2731 	u64			tick_delta;
2732 	u64			irq_start_time;
2733 	struct u64_stats_sync	sync;
2734 };
2735 
2736 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
2737 
2738 /*
2739  * Returns the irqtime minus the softirq time computed by ksoftirqd.
2740  * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime
2741  * and never move forward.
2742  */
2743 static inline u64 irq_time_read(int cpu)
2744 {
2745 	struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
2746 	unsigned int seq;
2747 	u64 total;
2748 
2749 	do {
2750 		seq = __u64_stats_fetch_begin(&irqtime->sync);
2751 		total = irqtime->total;
2752 	} while (__u64_stats_fetch_retry(&irqtime->sync, seq));
2753 
2754 	return total;
2755 }
2756 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
2757 
2758 #ifdef CONFIG_CPU_FREQ
2759 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
2760 
2761 /**
2762  * cpufreq_update_util - Take a note about CPU utilization changes.
2763  * @rq: Runqueue to carry out the update for.
2764  * @flags: Update reason flags.
2765  *
2766  * This function is called by the scheduler on the CPU whose utilization is
2767  * being updated.
2768  *
2769  * It can only be called from RCU-sched read-side critical sections.
2770  *
2771  * The way cpufreq is currently arranged requires it to evaluate the CPU
2772  * performance state (frequency/voltage) on a regular basis to prevent it from
2773  * being stuck in a completely inadequate performance level for too long.
2774  * That is not guaranteed to happen if the updates are only triggered from CFS
2775  * and DL, though, because they may not be coming in if only RT tasks are
2776  * active all the time (or there are RT tasks only).
2777  *
2778  * As a workaround for that issue, this function is called periodically by the
2779  * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
2780  * but that really is a band-aid.  Going forward it should be replaced with
2781  * solutions targeted more specifically at RT tasks.
2782  */
2783 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
2784 {
2785 	struct update_util_data *data;
2786 
2787 	data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
2788 						  cpu_of(rq)));
2789 	if (data)
2790 		data->func(data, rq_clock(rq), flags);
2791 }
2792 #else
2793 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
2794 #endif /* CONFIG_CPU_FREQ */
2795 
2796 #ifdef arch_scale_freq_capacity
2797 # ifndef arch_scale_freq_invariant
2798 #  define arch_scale_freq_invariant()	true
2799 # endif
2800 #else
2801 # define arch_scale_freq_invariant()	false
2802 #endif
2803 
2804 #ifdef CONFIG_SMP
2805 static inline unsigned long capacity_orig_of(int cpu)
2806 {
2807 	return cpu_rq(cpu)->cpu_capacity_orig;
2808 }
2809 
2810 /**
2811  * enum cpu_util_type - CPU utilization type
2812  * @FREQUENCY_UTIL:	Utilization used to select frequency
2813  * @ENERGY_UTIL:	Utilization used during energy calculation
2814  *
2815  * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time
2816  * need to be aggregated differently depending on the usage made of them. This
2817  * enum is used within effective_cpu_util() to differentiate the types of
2818  * utilization expected by the callers, and adjust the aggregation accordingly.
2819  */
2820 enum cpu_util_type {
2821 	FREQUENCY_UTIL,
2822 	ENERGY_UTIL,
2823 };
2824 
2825 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
2826 				 unsigned long max, enum cpu_util_type type,
2827 				 struct task_struct *p);
2828 
2829 static inline unsigned long cpu_bw_dl(struct rq *rq)
2830 {
2831 	return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
2832 }
2833 
2834 static inline unsigned long cpu_util_dl(struct rq *rq)
2835 {
2836 	return READ_ONCE(rq->avg_dl.util_avg);
2837 }
2838 
2839 /**
2840  * cpu_util_cfs() - Estimates the amount of CPU capacity used by CFS tasks.
2841  * @cpu: the CPU to get the utilization for.
2842  *
2843  * The unit of the return value must be the same as the one of CPU capacity
2844  * so that CPU utilization can be compared with CPU capacity.
2845  *
2846  * CPU utilization is the sum of running time of runnable tasks plus the
2847  * recent utilization of currently non-runnable tasks on that CPU.
2848  * It represents the amount of CPU capacity currently used by CFS tasks in
2849  * the range [0..max CPU capacity] with max CPU capacity being the CPU
2850  * capacity at f_max.
2851  *
2852  * The estimated CPU utilization is defined as the maximum between CPU
2853  * utilization and sum of the estimated utilization of the currently
2854  * runnable tasks on that CPU. It preserves a utilization "snapshot" of
2855  * previously-executed tasks, which helps better deduce how busy a CPU will
2856  * be when a long-sleeping task wakes up. The contribution to CPU utilization
2857  * of such a task would be significantly decayed at this point of time.
2858  *
2859  * CPU utilization can be higher than the current CPU capacity
2860  * (f_curr/f_max * max CPU capacity) or even the max CPU capacity because
2861  * of rounding errors as well as task migrations or wakeups of new tasks.
2862  * CPU utilization has to be capped to fit into the [0..max CPU capacity]
2863  * range. Otherwise a group of CPUs (CPU0 util = 121% + CPU1 util = 80%)
2864  * could be seen as over-utilized even though CPU1 has 20% of spare CPU
2865  * capacity. CPU utilization is allowed to overshoot current CPU capacity
2866  * though since this is useful for predicting the CPU capacity required
2867  * after task migrations (scheduler-driven DVFS).
2868  *
2869  * Return: (Estimated) utilization for the specified CPU.
2870  */
2871 static inline unsigned long cpu_util_cfs(int cpu)
2872 {
2873 	struct cfs_rq *cfs_rq;
2874 	unsigned long util;
2875 
2876 	cfs_rq = &cpu_rq(cpu)->cfs;
2877 	util = READ_ONCE(cfs_rq->avg.util_avg);
2878 
2879 	if (sched_feat(UTIL_EST)) {
2880 		util = max_t(unsigned long, util,
2881 			     READ_ONCE(cfs_rq->avg.util_est.enqueued));
2882 	}
2883 
2884 	return min(util, capacity_orig_of(cpu));
2885 }
2886 
2887 static inline unsigned long cpu_util_rt(struct rq *rq)
2888 {
2889 	return READ_ONCE(rq->avg_rt.util_avg);
2890 }
2891 #endif
2892 
2893 #ifdef CONFIG_UCLAMP_TASK
2894 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
2895 
2896 /**
2897  * uclamp_rq_util_with - clamp @util with @rq and @p effective uclamp values.
2898  * @rq:		The rq to clamp against. Must not be NULL.
2899  * @util:	The util value to clamp.
2900  * @p:		The task to clamp against. Can be NULL if you want to clamp
2901  *		against @rq only.
2902  *
2903  * Clamps the passed @util to the max(@rq, @p) effective uclamp values.
2904  *
2905  * If sched_uclamp_used static key is disabled, then just return the util
2906  * without any clamping since uclamp aggregation at the rq level in the fast
2907  * path is disabled, rendering this operation a NOP.
2908  *
2909  * Use uclamp_eff_value() if you don't care about uclamp values at rq level. It
2910  * will return the correct effective uclamp value of the task even if the
2911  * static key is disabled.
2912  */
2913 static __always_inline
2914 unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
2915 				  struct task_struct *p)
2916 {
2917 	unsigned long min_util = 0;
2918 	unsigned long max_util = 0;
2919 
2920 	if (!static_branch_likely(&sched_uclamp_used))
2921 		return util;
2922 
2923 	if (p) {
2924 		min_util = uclamp_eff_value(p, UCLAMP_MIN);
2925 		max_util = uclamp_eff_value(p, UCLAMP_MAX);
2926 
2927 		/*
2928 		 * Ignore last runnable task's max clamp, as this task will
2929 		 * reset it. Similarly, no need to read the rq's min clamp.
2930 		 */
2931 		if (rq->uclamp_flags & UCLAMP_FLAG_IDLE)
2932 			goto out;
2933 	}
2934 
2935 	min_util = max_t(unsigned long, min_util, READ_ONCE(rq->uclamp[UCLAMP_MIN].value));
2936 	max_util = max_t(unsigned long, max_util, READ_ONCE(rq->uclamp[UCLAMP_MAX].value));
2937 out:
2938 	/*
2939 	 * Since CPU's {min,max}_util clamps are MAX aggregated considering
2940 	 * RUNNABLE tasks with _different_ clamps, we can end up with an
2941 	 * inversion. Fix it now when the clamps are applied.
2942 	 */
2943 	if (unlikely(min_util >= max_util))
2944 		return min_util;
2945 
2946 	return clamp(util, min_util, max_util);
2947 }
2948 
2949 /* Is the rq being capped/throttled by uclamp_max? */
2950 static inline bool uclamp_rq_is_capped(struct rq *rq)
2951 {
2952 	unsigned long rq_util;
2953 	unsigned long max_util;
2954 
2955 	if (!static_branch_likely(&sched_uclamp_used))
2956 		return false;
2957 
2958 	rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq);
2959 	max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
2960 
2961 	return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util;
2962 }
2963 
2964 /*
2965  * When uclamp is compiled in, the aggregation at rq level is 'turned off'
2966  * by default in the fast path and only gets turned on once userspace performs
2967  * an operation that requires it.
2968  *
2969  * Returns true if userspace opted-in to use uclamp and aggregation at rq level
2970  * hence is active.
2971  */
2972 static inline bool uclamp_is_used(void)
2973 {
2974 	return static_branch_likely(&sched_uclamp_used);
2975 }
2976 #else /* CONFIG_UCLAMP_TASK */
2977 static inline
2978 unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
2979 				  struct task_struct *p)
2980 {
2981 	return util;
2982 }
2983 
2984 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; }
2985 
2986 static inline bool uclamp_is_used(void)
2987 {
2988 	return false;
2989 }
2990 #endif /* CONFIG_UCLAMP_TASK */
2991 
2992 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
2993 static inline unsigned long cpu_util_irq(struct rq *rq)
2994 {
2995 	return rq->avg_irq.util_avg;
2996 }
2997 
2998 static inline
2999 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3000 {
3001 	util *= (max - irq);
3002 	util /= max;
3003 
3004 	return util;
3005 
3006 }
3007 #else
3008 static inline unsigned long cpu_util_irq(struct rq *rq)
3009 {
3010 	return 0;
3011 }
3012 
3013 static inline
3014 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3015 {
3016 	return util;
3017 }
3018 #endif
3019 
3020 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
3021 
3022 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
3023 
3024 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
3025 
3026 static inline bool sched_energy_enabled(void)
3027 {
3028 	return static_branch_unlikely(&sched_energy_present);
3029 }
3030 
3031 #else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
3032 
3033 #define perf_domain_span(pd) NULL
3034 static inline bool sched_energy_enabled(void) { return false; }
3035 
3036 #endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
3037 
3038 #ifdef CONFIG_MEMBARRIER
3039 /*
3040  * The scheduler provides memory barriers required by membarrier between:
3041  * - prior user-space memory accesses and store to rq->membarrier_state,
3042  * - store to rq->membarrier_state and following user-space memory accesses.
3043  * In the same way it provides those guarantees around store to rq->curr.
3044  */
3045 static inline void membarrier_switch_mm(struct rq *rq,
3046 					struct mm_struct *prev_mm,
3047 					struct mm_struct *next_mm)
3048 {
3049 	int membarrier_state;
3050 
3051 	if (prev_mm == next_mm)
3052 		return;
3053 
3054 	membarrier_state = atomic_read(&next_mm->membarrier_state);
3055 	if (READ_ONCE(rq->membarrier_state) == membarrier_state)
3056 		return;
3057 
3058 	WRITE_ONCE(rq->membarrier_state, membarrier_state);
3059 }
3060 #else
3061 static inline void membarrier_switch_mm(struct rq *rq,
3062 					struct mm_struct *prev_mm,
3063 					struct mm_struct *next_mm)
3064 {
3065 }
3066 #endif
3067 
3068 #ifdef CONFIG_SMP
3069 static inline bool is_per_cpu_kthread(struct task_struct *p)
3070 {
3071 	if (!(p->flags & PF_KTHREAD))
3072 		return false;
3073 
3074 	if (p->nr_cpus_allowed != 1)
3075 		return false;
3076 
3077 	return true;
3078 }
3079 #endif
3080 
3081 extern void swake_up_all_locked(struct swait_queue_head *q);
3082 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
3083 
3084 #ifdef CONFIG_PREEMPT_DYNAMIC
3085 extern int preempt_dynamic_mode;
3086 extern int sched_dynamic_mode(const char *str);
3087 extern void sched_dynamic_update(int mode);
3088 #endif
3089 
3090 #endif /* _KERNEL_SCHED_SCHED_H */
3091