xref: /openbmc/linux/kernel/sched/sched.h (revision 278d3ba6)
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/context_tracking.h>
31 #include <linux/cpufreq.h>
32 #include <linux/cpumask_api.h>
33 #include <linux/ctype.h>
34 #include <linux/file.h>
35 #include <linux/fs_api.h>
36 #include <linux/hrtimer_api.h>
37 #include <linux/interrupt.h>
38 #include <linux/irq_work.h>
39 #include <linux/jiffies.h>
40 #include <linux/kref_api.h>
41 #include <linux/kthread.h>
42 #include <linux/ktime_api.h>
43 #include <linux/lockdep_api.h>
44 #include <linux/lockdep.h>
45 #include <linux/minmax.h>
46 #include <linux/mm.h>
47 #include <linux/module.h>
48 #include <linux/mutex_api.h>
49 #include <linux/plist.h>
50 #include <linux/poll.h>
51 #include <linux/proc_fs.h>
52 #include <linux/profile.h>
53 #include <linux/psi.h>
54 #include <linux/rcupdate.h>
55 #include <linux/seq_file.h>
56 #include <linux/seqlock.h>
57 #include <linux/softirq.h>
58 #include <linux/spinlock_api.h>
59 #include <linux/static_key.h>
60 #include <linux/stop_machine.h>
61 #include <linux/syscalls_api.h>
62 #include <linux/syscalls.h>
63 #include <linux/tick.h>
64 #include <linux/topology.h>
65 #include <linux/types.h>
66 #include <linux/u64_stats_sync_api.h>
67 #include <linux/uaccess.h>
68 #include <linux/wait_api.h>
69 #include <linux/wait_bit.h>
70 #include <linux/workqueue_api.h>
71 
72 #include <trace/events/power.h>
73 #include <trace/events/sched.h>
74 
75 #include "../workqueue_internal.h"
76 
77 #ifdef CONFIG_CGROUP_SCHED
78 #include <linux/cgroup.h>
79 #include <linux/psi.h>
80 #endif
81 
82 #ifdef CONFIG_SCHED_DEBUG
83 # include <linux/static_key.h>
84 #endif
85 
86 #ifdef CONFIG_PARAVIRT
87 # include <asm/paravirt.h>
88 # include <asm/paravirt_api_clock.h>
89 #endif
90 
91 #include "cpupri.h"
92 #include "cpudeadline.h"
93 
94 #ifdef CONFIG_SCHED_DEBUG
95 # define SCHED_WARN_ON(x)      WARN_ONCE(x, #x)
96 #else
97 # define SCHED_WARN_ON(x)      ({ (void)(x), 0; })
98 #endif
99 
100 struct rq;
101 struct cpuidle_state;
102 
103 /* task_struct::on_rq states: */
104 #define TASK_ON_RQ_QUEUED	1
105 #define TASK_ON_RQ_MIGRATING	2
106 
107 extern __read_mostly int scheduler_running;
108 
109 extern unsigned long calc_load_update;
110 extern atomic_long_t calc_load_tasks;
111 
112 extern unsigned int sysctl_sched_child_runs_first;
113 
114 extern void calc_global_load_tick(struct rq *this_rq);
115 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
116 
117 extern void call_trace_sched_update_nr_running(struct rq *rq, int count);
118 
119 extern unsigned int sysctl_sched_rt_period;
120 extern int sysctl_sched_rt_runtime;
121 extern int sched_rr_timeslice;
122 
123 /*
124  * Helpers for converting nanosecond timing to jiffy resolution
125  */
126 #define NS_TO_JIFFIES(TIME)	((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
127 
128 /*
129  * Increase resolution of nice-level calculations for 64-bit architectures.
130  * The extra resolution improves shares distribution and load balancing of
131  * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
132  * hierarchies, especially on larger systems. This is not a user-visible change
133  * and does not change the user-interface for setting shares/weights.
134  *
135  * We increase resolution only if we have enough bits to allow this increased
136  * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
137  * are pretty high and the returns do not justify the increased costs.
138  *
139  * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
140  * increase coverage and consistency always enable it on 64-bit platforms.
141  */
142 #ifdef CONFIG_64BIT
143 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
144 # define scale_load(w)		((w) << SCHED_FIXEDPOINT_SHIFT)
145 # define scale_load_down(w) \
146 ({ \
147 	unsigned long __w = (w); \
148 	if (__w) \
149 		__w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \
150 	__w; \
151 })
152 #else
153 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT)
154 # define scale_load(w)		(w)
155 # define scale_load_down(w)	(w)
156 #endif
157 
158 /*
159  * Task weight (visible to users) and its load (invisible to users) have
160  * independent resolution, but they should be well calibrated. We use
161  * scale_load() and scale_load_down(w) to convert between them. The
162  * following must be true:
163  *
164  *  scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD
165  *
166  */
167 #define NICE_0_LOAD		(1L << NICE_0_LOAD_SHIFT)
168 
169 /*
170  * Single value that decides SCHED_DEADLINE internal math precision.
171  * 10 -> just above 1us
172  * 9  -> just above 0.5us
173  */
174 #define DL_SCALE		10
175 
176 /*
177  * Single value that denotes runtime == period, ie unlimited time.
178  */
179 #define RUNTIME_INF		((u64)~0ULL)
180 
181 static inline int idle_policy(int policy)
182 {
183 	return policy == SCHED_IDLE;
184 }
185 static inline int fair_policy(int policy)
186 {
187 	return policy == SCHED_NORMAL || policy == SCHED_BATCH;
188 }
189 
190 static inline int rt_policy(int policy)
191 {
192 	return policy == SCHED_FIFO || policy == SCHED_RR;
193 }
194 
195 static inline int dl_policy(int policy)
196 {
197 	return policy == SCHED_DEADLINE;
198 }
199 static inline bool valid_policy(int policy)
200 {
201 	return idle_policy(policy) || fair_policy(policy) ||
202 		rt_policy(policy) || dl_policy(policy);
203 }
204 
205 static inline int task_has_idle_policy(struct task_struct *p)
206 {
207 	return idle_policy(p->policy);
208 }
209 
210 static inline int task_has_rt_policy(struct task_struct *p)
211 {
212 	return rt_policy(p->policy);
213 }
214 
215 static inline int task_has_dl_policy(struct task_struct *p)
216 {
217 	return dl_policy(p->policy);
218 }
219 
220 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
221 
222 static inline void update_avg(u64 *avg, u64 sample)
223 {
224 	s64 diff = sample - *avg;
225 	*avg += diff / 8;
226 }
227 
228 /*
229  * Shifting a value by an exponent greater *or equal* to the size of said value
230  * is UB; cap at size-1.
231  */
232 #define shr_bound(val, shift)							\
233 	(val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1))
234 
235 /*
236  * !! For sched_setattr_nocheck() (kernel) only !!
237  *
238  * This is actually gross. :(
239  *
240  * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
241  * tasks, but still be able to sleep. We need this on platforms that cannot
242  * atomically change clock frequency. Remove once fast switching will be
243  * available on such platforms.
244  *
245  * SUGOV stands for SchedUtil GOVernor.
246  */
247 #define SCHED_FLAG_SUGOV	0x10000000
248 
249 #define SCHED_DL_FLAGS (SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV)
250 
251 static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se)
252 {
253 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
254 	return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
255 #else
256 	return false;
257 #endif
258 }
259 
260 /*
261  * Tells if entity @a should preempt entity @b.
262  */
263 static inline bool
264 dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
265 {
266 	return dl_entity_is_special(a) ||
267 	       dl_time_before(a->deadline, b->deadline);
268 }
269 
270 /*
271  * This is the priority-queue data structure of the RT scheduling class:
272  */
273 struct rt_prio_array {
274 	DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
275 	struct list_head queue[MAX_RT_PRIO];
276 };
277 
278 struct rt_bandwidth {
279 	/* nests inside the rq lock: */
280 	raw_spinlock_t		rt_runtime_lock;
281 	ktime_t			rt_period;
282 	u64			rt_runtime;
283 	struct hrtimer		rt_period_timer;
284 	unsigned int		rt_period_active;
285 };
286 
287 void __dl_clear_params(struct task_struct *p);
288 
289 struct dl_bandwidth {
290 	raw_spinlock_t		dl_runtime_lock;
291 	u64			dl_runtime;
292 	u64			dl_period;
293 };
294 
295 static inline int dl_bandwidth_enabled(void)
296 {
297 	return sysctl_sched_rt_runtime >= 0;
298 }
299 
300 /*
301  * To keep the bandwidth of -deadline tasks under control
302  * we need some place where:
303  *  - store the maximum -deadline bandwidth of each cpu;
304  *  - cache the fraction of bandwidth that is currently allocated in
305  *    each root domain;
306  *
307  * This is all done in the data structure below. It is similar to the
308  * one used for RT-throttling (rt_bandwidth), with the main difference
309  * that, since here we are only interested in admission control, we
310  * do not decrease any runtime while the group "executes", neither we
311  * need a timer to replenish it.
312  *
313  * With respect to SMP, bandwidth is given on a per root domain basis,
314  * meaning that:
315  *  - bw (< 100%) is the deadline bandwidth of each CPU;
316  *  - total_bw is the currently allocated bandwidth in each root domain;
317  */
318 struct dl_bw {
319 	raw_spinlock_t		lock;
320 	u64			bw;
321 	u64			total_bw;
322 };
323 
324 /*
325  * Verify the fitness of task @p to run on @cpu taking into account the
326  * CPU original capacity and the runtime/deadline ratio of the task.
327  *
328  * The function will return true if the CPU original capacity of the
329  * @cpu scaled by SCHED_CAPACITY_SCALE >= runtime/deadline ratio of the
330  * task and false otherwise.
331  */
332 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
333 {
334 	unsigned long cap = arch_scale_cpu_capacity(cpu);
335 
336 	return cap_scale(p->dl.dl_deadline, cap) >= p->dl.dl_runtime;
337 }
338 
339 extern void init_dl_bw(struct dl_bw *dl_b);
340 extern int  sched_dl_global_validate(void);
341 extern void sched_dl_do_global(void);
342 extern int  sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
343 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
344 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
345 extern bool __checkparam_dl(const struct sched_attr *attr);
346 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
347 extern int  dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
348 extern int  dl_cpu_busy(int cpu, struct task_struct *p);
349 
350 #ifdef CONFIG_CGROUP_SCHED
351 
352 struct cfs_rq;
353 struct rt_rq;
354 
355 extern struct list_head task_groups;
356 
357 struct cfs_bandwidth {
358 #ifdef CONFIG_CFS_BANDWIDTH
359 	raw_spinlock_t		lock;
360 	ktime_t			period;
361 	u64			quota;
362 	u64			runtime;
363 	u64			burst;
364 	u64			runtime_snap;
365 	s64			hierarchical_quota;
366 
367 	u8			idle;
368 	u8			period_active;
369 	u8			slack_started;
370 	struct hrtimer		period_timer;
371 	struct hrtimer		slack_timer;
372 	struct list_head	throttled_cfs_rq;
373 
374 	/* Statistics: */
375 	int			nr_periods;
376 	int			nr_throttled;
377 	int			nr_burst;
378 	u64			throttled_time;
379 	u64			burst_time;
380 #endif
381 };
382 
383 /* Task group related information */
384 struct task_group {
385 	struct cgroup_subsys_state css;
386 
387 #ifdef CONFIG_FAIR_GROUP_SCHED
388 	/* schedulable entities of this group on each CPU */
389 	struct sched_entity	**se;
390 	/* runqueue "owned" by this group on each CPU */
391 	struct cfs_rq		**cfs_rq;
392 	unsigned long		shares;
393 
394 	/* A positive value indicates that this is a SCHED_IDLE group. */
395 	int			idle;
396 
397 #ifdef	CONFIG_SMP
398 	/*
399 	 * load_avg can be heavily contended at clock tick time, so put
400 	 * it in its own cacheline separated from the fields above which
401 	 * will also be accessed at each tick.
402 	 */
403 	atomic_long_t		load_avg ____cacheline_aligned;
404 #endif
405 #endif
406 
407 #ifdef CONFIG_RT_GROUP_SCHED
408 	struct sched_rt_entity	**rt_se;
409 	struct rt_rq		**rt_rq;
410 
411 	struct rt_bandwidth	rt_bandwidth;
412 #endif
413 
414 	struct rcu_head		rcu;
415 	struct list_head	list;
416 
417 	struct task_group	*parent;
418 	struct list_head	siblings;
419 	struct list_head	children;
420 
421 #ifdef CONFIG_SCHED_AUTOGROUP
422 	struct autogroup	*autogroup;
423 #endif
424 
425 	struct cfs_bandwidth	cfs_bandwidth;
426 
427 #ifdef CONFIG_UCLAMP_TASK_GROUP
428 	/* The two decimal precision [%] value requested from user-space */
429 	unsigned int		uclamp_pct[UCLAMP_CNT];
430 	/* Clamp values requested for a task group */
431 	struct uclamp_se	uclamp_req[UCLAMP_CNT];
432 	/* Effective clamp values used for a task group */
433 	struct uclamp_se	uclamp[UCLAMP_CNT];
434 #endif
435 
436 };
437 
438 #ifdef CONFIG_FAIR_GROUP_SCHED
439 #define ROOT_TASK_GROUP_LOAD	NICE_0_LOAD
440 
441 /*
442  * A weight of 0 or 1 can cause arithmetics problems.
443  * A weight of a cfs_rq is the sum of weights of which entities
444  * are queued on this cfs_rq, so a weight of a entity should not be
445  * too large, so as the shares value of a task group.
446  * (The default weight is 1024 - so there's no practical
447  *  limitation from this.)
448  */
449 #define MIN_SHARES		(1UL <<  1)
450 #define MAX_SHARES		(1UL << 18)
451 #endif
452 
453 typedef int (*tg_visitor)(struct task_group *, void *);
454 
455 extern int walk_tg_tree_from(struct task_group *from,
456 			     tg_visitor down, tg_visitor up, void *data);
457 
458 /*
459  * Iterate the full tree, calling @down when first entering a node and @up when
460  * leaving it for the final time.
461  *
462  * Caller must hold rcu_lock or sufficient equivalent.
463  */
464 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
465 {
466 	return walk_tg_tree_from(&root_task_group, down, up, data);
467 }
468 
469 extern int tg_nop(struct task_group *tg, void *data);
470 
471 extern void free_fair_sched_group(struct task_group *tg);
472 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
473 extern void online_fair_sched_group(struct task_group *tg);
474 extern void unregister_fair_sched_group(struct task_group *tg);
475 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
476 			struct sched_entity *se, int cpu,
477 			struct sched_entity *parent);
478 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
479 
480 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
481 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
482 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
483 
484 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
485 		struct sched_rt_entity *rt_se, int cpu,
486 		struct sched_rt_entity *parent);
487 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
488 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
489 extern long sched_group_rt_runtime(struct task_group *tg);
490 extern long sched_group_rt_period(struct task_group *tg);
491 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
492 
493 extern struct task_group *sched_create_group(struct task_group *parent);
494 extern void sched_online_group(struct task_group *tg,
495 			       struct task_group *parent);
496 extern void sched_destroy_group(struct task_group *tg);
497 extern void sched_release_group(struct task_group *tg);
498 
499 extern void sched_move_task(struct task_struct *tsk);
500 
501 #ifdef CONFIG_FAIR_GROUP_SCHED
502 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
503 
504 extern int sched_group_set_idle(struct task_group *tg, long idle);
505 
506 #ifdef CONFIG_SMP
507 extern void set_task_rq_fair(struct sched_entity *se,
508 			     struct cfs_rq *prev, struct cfs_rq *next);
509 #else /* !CONFIG_SMP */
510 static inline void set_task_rq_fair(struct sched_entity *se,
511 			     struct cfs_rq *prev, struct cfs_rq *next) { }
512 #endif /* CONFIG_SMP */
513 #endif /* CONFIG_FAIR_GROUP_SCHED */
514 
515 #else /* CONFIG_CGROUP_SCHED */
516 
517 struct cfs_bandwidth { };
518 
519 #endif	/* CONFIG_CGROUP_SCHED */
520 
521 extern void unregister_rt_sched_group(struct task_group *tg);
522 extern void free_rt_sched_group(struct task_group *tg);
523 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
524 
525 /*
526  * u64_u32_load/u64_u32_store
527  *
528  * Use a copy of a u64 value to protect against data race. This is only
529  * applicable for 32-bits architectures.
530  */
531 #ifdef CONFIG_64BIT
532 # define u64_u32_load_copy(var, copy)       var
533 # define u64_u32_store_copy(var, copy, val) (var = val)
534 #else
535 # define u64_u32_load_copy(var, copy)					\
536 ({									\
537 	u64 __val, __val_copy;						\
538 	do {								\
539 		__val_copy = copy;					\
540 		/*							\
541 		 * paired with u64_u32_store_copy(), ordering access	\
542 		 * to var and copy.					\
543 		 */							\
544 		smp_rmb();						\
545 		__val = var;						\
546 	} while (__val != __val_copy);					\
547 	__val;								\
548 })
549 # define u64_u32_store_copy(var, copy, val)				\
550 do {									\
551 	typeof(val) __val = (val);					\
552 	var = __val;							\
553 	/*								\
554 	 * paired with u64_u32_load_copy(), ordering access to var and	\
555 	 * copy.							\
556 	 */								\
557 	smp_wmb();							\
558 	copy = __val;							\
559 } while (0)
560 #endif
561 # define u64_u32_load(var)      u64_u32_load_copy(var, var##_copy)
562 # define u64_u32_store(var, val) u64_u32_store_copy(var, var##_copy, val)
563 
564 /* CFS-related fields in a runqueue */
565 struct cfs_rq {
566 	struct load_weight	load;
567 	unsigned int		nr_running;
568 	unsigned int		h_nr_running;      /* SCHED_{NORMAL,BATCH,IDLE} */
569 	unsigned int		idle_nr_running;   /* SCHED_IDLE */
570 	unsigned int		idle_h_nr_running; /* SCHED_IDLE */
571 
572 	u64			exec_clock;
573 	u64			min_vruntime;
574 #ifdef CONFIG_SCHED_CORE
575 	unsigned int		forceidle_seq;
576 	u64			min_vruntime_fi;
577 #endif
578 
579 #ifndef CONFIG_64BIT
580 	u64			min_vruntime_copy;
581 #endif
582 
583 	struct rb_root_cached	tasks_timeline;
584 
585 	/*
586 	 * 'curr' points to currently running entity on this cfs_rq.
587 	 * It is set to NULL otherwise (i.e when none are currently running).
588 	 */
589 	struct sched_entity	*curr;
590 	struct sched_entity	*next;
591 	struct sched_entity	*last;
592 	struct sched_entity	*skip;
593 
594 #ifdef	CONFIG_SCHED_DEBUG
595 	unsigned int		nr_spread_over;
596 #endif
597 
598 #ifdef CONFIG_SMP
599 	/*
600 	 * CFS load tracking
601 	 */
602 	struct sched_avg	avg;
603 #ifndef CONFIG_64BIT
604 	u64			last_update_time_copy;
605 #endif
606 	struct {
607 		raw_spinlock_t	lock ____cacheline_aligned;
608 		int		nr;
609 		unsigned long	load_avg;
610 		unsigned long	util_avg;
611 		unsigned long	runnable_avg;
612 	} removed;
613 
614 #ifdef CONFIG_FAIR_GROUP_SCHED
615 	unsigned long		tg_load_avg_contrib;
616 	long			propagate;
617 	long			prop_runnable_sum;
618 
619 	/*
620 	 *   h_load = weight * f(tg)
621 	 *
622 	 * Where f(tg) is the recursive weight fraction assigned to
623 	 * this group.
624 	 */
625 	unsigned long		h_load;
626 	u64			last_h_load_update;
627 	struct sched_entity	*h_load_next;
628 #endif /* CONFIG_FAIR_GROUP_SCHED */
629 #endif /* CONFIG_SMP */
630 
631 #ifdef CONFIG_FAIR_GROUP_SCHED
632 	struct rq		*rq;	/* CPU runqueue to which this cfs_rq is attached */
633 
634 	/*
635 	 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
636 	 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
637 	 * (like users, containers etc.)
638 	 *
639 	 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
640 	 * This list is used during load balance.
641 	 */
642 	int			on_list;
643 	struct list_head	leaf_cfs_rq_list;
644 	struct task_group	*tg;	/* group that "owns" this runqueue */
645 
646 	/* Locally cached copy of our task_group's idle value */
647 	int			idle;
648 
649 #ifdef CONFIG_CFS_BANDWIDTH
650 	int			runtime_enabled;
651 	s64			runtime_remaining;
652 
653 	u64			throttled_pelt_idle;
654 #ifndef CONFIG_64BIT
655 	u64                     throttled_pelt_idle_copy;
656 #endif
657 	u64			throttled_clock;
658 	u64			throttled_clock_pelt;
659 	u64			throttled_clock_pelt_time;
660 	int			throttled;
661 	int			throttle_count;
662 	struct list_head	throttled_list;
663 #endif /* CONFIG_CFS_BANDWIDTH */
664 #endif /* CONFIG_FAIR_GROUP_SCHED */
665 };
666 
667 static inline int rt_bandwidth_enabled(void)
668 {
669 	return sysctl_sched_rt_runtime >= 0;
670 }
671 
672 /* RT IPI pull logic requires IRQ_WORK */
673 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
674 # define HAVE_RT_PUSH_IPI
675 #endif
676 
677 /* Real-Time classes' related field in a runqueue: */
678 struct rt_rq {
679 	struct rt_prio_array	active;
680 	unsigned int		rt_nr_running;
681 	unsigned int		rr_nr_running;
682 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
683 	struct {
684 		int		curr; /* highest queued rt task prio */
685 #ifdef CONFIG_SMP
686 		int		next; /* next highest */
687 #endif
688 	} highest_prio;
689 #endif
690 #ifdef CONFIG_SMP
691 	unsigned int		rt_nr_migratory;
692 	unsigned int		rt_nr_total;
693 	int			overloaded;
694 	struct plist_head	pushable_tasks;
695 
696 #endif /* CONFIG_SMP */
697 	int			rt_queued;
698 
699 	int			rt_throttled;
700 	u64			rt_time;
701 	u64			rt_runtime;
702 	/* Nests inside the rq lock: */
703 	raw_spinlock_t		rt_runtime_lock;
704 
705 #ifdef CONFIG_RT_GROUP_SCHED
706 	unsigned int		rt_nr_boosted;
707 
708 	struct rq		*rq;
709 	struct task_group	*tg;
710 #endif
711 };
712 
713 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
714 {
715 	return rt_rq->rt_queued && rt_rq->rt_nr_running;
716 }
717 
718 /* Deadline class' related fields in a runqueue */
719 struct dl_rq {
720 	/* runqueue is an rbtree, ordered by deadline */
721 	struct rb_root_cached	root;
722 
723 	unsigned int		dl_nr_running;
724 
725 #ifdef CONFIG_SMP
726 	/*
727 	 * Deadline values of the currently executing and the
728 	 * earliest ready task on this rq. Caching these facilitates
729 	 * the decision whether or not a ready but not running task
730 	 * should migrate somewhere else.
731 	 */
732 	struct {
733 		u64		curr;
734 		u64		next;
735 	} earliest_dl;
736 
737 	unsigned int		dl_nr_migratory;
738 	int			overloaded;
739 
740 	/*
741 	 * Tasks on this rq that can be pushed away. They are kept in
742 	 * an rb-tree, ordered by tasks' deadlines, with caching
743 	 * of the leftmost (earliest deadline) element.
744 	 */
745 	struct rb_root_cached	pushable_dl_tasks_root;
746 #else
747 	struct dl_bw		dl_bw;
748 #endif
749 	/*
750 	 * "Active utilization" for this runqueue: increased when a
751 	 * task wakes up (becomes TASK_RUNNING) and decreased when a
752 	 * task blocks
753 	 */
754 	u64			running_bw;
755 
756 	/*
757 	 * Utilization of the tasks "assigned" to this runqueue (including
758 	 * the tasks that are in runqueue and the tasks that executed on this
759 	 * CPU and blocked). Increased when a task moves to this runqueue, and
760 	 * decreased when the task moves away (migrates, changes scheduling
761 	 * policy, or terminates).
762 	 * This is needed to compute the "inactive utilization" for the
763 	 * runqueue (inactive utilization = this_bw - running_bw).
764 	 */
765 	u64			this_bw;
766 	u64			extra_bw;
767 
768 	/*
769 	 * Inverse of the fraction of CPU utilization that can be reclaimed
770 	 * by the GRUB algorithm.
771 	 */
772 	u64			bw_ratio;
773 };
774 
775 #ifdef CONFIG_FAIR_GROUP_SCHED
776 /* An entity is a task if it doesn't "own" a runqueue */
777 #define entity_is_task(se)	(!se->my_q)
778 
779 static inline void se_update_runnable(struct sched_entity *se)
780 {
781 	if (!entity_is_task(se))
782 		se->runnable_weight = se->my_q->h_nr_running;
783 }
784 
785 static inline long se_runnable(struct sched_entity *se)
786 {
787 	if (entity_is_task(se))
788 		return !!se->on_rq;
789 	else
790 		return se->runnable_weight;
791 }
792 
793 #else
794 #define entity_is_task(se)	1
795 
796 static inline void se_update_runnable(struct sched_entity *se) {}
797 
798 static inline long se_runnable(struct sched_entity *se)
799 {
800 	return !!se->on_rq;
801 }
802 #endif
803 
804 #ifdef CONFIG_SMP
805 /*
806  * XXX we want to get rid of these helpers and use the full load resolution.
807  */
808 static inline long se_weight(struct sched_entity *se)
809 {
810 	return scale_load_down(se->load.weight);
811 }
812 
813 
814 static inline bool sched_asym_prefer(int a, int b)
815 {
816 	return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
817 }
818 
819 struct perf_domain {
820 	struct em_perf_domain *em_pd;
821 	struct perf_domain *next;
822 	struct rcu_head rcu;
823 };
824 
825 /* Scheduling group status flags */
826 #define SG_OVERLOAD		0x1 /* More than one runnable task on a CPU. */
827 #define SG_OVERUTILIZED		0x2 /* One or more CPUs are over-utilized. */
828 
829 /*
830  * We add the notion of a root-domain which will be used to define per-domain
831  * variables. Each exclusive cpuset essentially defines an island domain by
832  * fully partitioning the member CPUs from any other cpuset. Whenever a new
833  * exclusive cpuset is created, we also create and attach a new root-domain
834  * object.
835  *
836  */
837 struct root_domain {
838 	atomic_t		refcount;
839 	atomic_t		rto_count;
840 	struct rcu_head		rcu;
841 	cpumask_var_t		span;
842 	cpumask_var_t		online;
843 
844 	/*
845 	 * Indicate pullable load on at least one CPU, e.g:
846 	 * - More than one runnable task
847 	 * - Running task is misfit
848 	 */
849 	int			overload;
850 
851 	/* Indicate one or more cpus over-utilized (tipping point) */
852 	int			overutilized;
853 
854 	/*
855 	 * The bit corresponding to a CPU gets set here if such CPU has more
856 	 * than one runnable -deadline task (as it is below for RT tasks).
857 	 */
858 	cpumask_var_t		dlo_mask;
859 	atomic_t		dlo_count;
860 	struct dl_bw		dl_bw;
861 	struct cpudl		cpudl;
862 
863 	/*
864 	 * Indicate whether a root_domain's dl_bw has been checked or
865 	 * updated. It's monotonously increasing value.
866 	 *
867 	 * Also, some corner cases, like 'wrap around' is dangerous, but given
868 	 * that u64 is 'big enough'. So that shouldn't be a concern.
869 	 */
870 	u64 visit_gen;
871 
872 #ifdef HAVE_RT_PUSH_IPI
873 	/*
874 	 * For IPI pull requests, loop across the rto_mask.
875 	 */
876 	struct irq_work		rto_push_work;
877 	raw_spinlock_t		rto_lock;
878 	/* These are only updated and read within rto_lock */
879 	int			rto_loop;
880 	int			rto_cpu;
881 	/* These atomics are updated outside of a lock */
882 	atomic_t		rto_loop_next;
883 	atomic_t		rto_loop_start;
884 #endif
885 	/*
886 	 * The "RT overload" flag: it gets set if a CPU has more than
887 	 * one runnable RT task.
888 	 */
889 	cpumask_var_t		rto_mask;
890 	struct cpupri		cpupri;
891 
892 	unsigned long		max_cpu_capacity;
893 
894 	/*
895 	 * NULL-terminated list of performance domains intersecting with the
896 	 * CPUs of the rd. Protected by RCU.
897 	 */
898 	struct perf_domain __rcu *pd;
899 };
900 
901 extern void init_defrootdomain(void);
902 extern int sched_init_domains(const struct cpumask *cpu_map);
903 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
904 extern void sched_get_rd(struct root_domain *rd);
905 extern void sched_put_rd(struct root_domain *rd);
906 
907 #ifdef HAVE_RT_PUSH_IPI
908 extern void rto_push_irq_work_func(struct irq_work *work);
909 #endif
910 #endif /* CONFIG_SMP */
911 
912 #ifdef CONFIG_UCLAMP_TASK
913 /*
914  * struct uclamp_bucket - Utilization clamp bucket
915  * @value: utilization clamp value for tasks on this clamp bucket
916  * @tasks: number of RUNNABLE tasks on this clamp bucket
917  *
918  * Keep track of how many tasks are RUNNABLE for a given utilization
919  * clamp value.
920  */
921 struct uclamp_bucket {
922 	unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
923 	unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
924 };
925 
926 /*
927  * struct uclamp_rq - rq's utilization clamp
928  * @value: currently active clamp values for a rq
929  * @bucket: utilization clamp buckets affecting a rq
930  *
931  * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
932  * A clamp value is affecting a rq when there is at least one task RUNNABLE
933  * (or actually running) with that value.
934  *
935  * There are up to UCLAMP_CNT possible different clamp values, currently there
936  * are only two: minimum utilization and maximum utilization.
937  *
938  * All utilization clamping values are MAX aggregated, since:
939  * - for util_min: we want to run the CPU at least at the max of the minimum
940  *   utilization required by its currently RUNNABLE tasks.
941  * - for util_max: we want to allow the CPU to run up to the max of the
942  *   maximum utilization allowed by its currently RUNNABLE tasks.
943  *
944  * Since on each system we expect only a limited number of different
945  * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
946  * the metrics required to compute all the per-rq utilization clamp values.
947  */
948 struct uclamp_rq {
949 	unsigned int value;
950 	struct uclamp_bucket bucket[UCLAMP_BUCKETS];
951 };
952 
953 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
954 #endif /* CONFIG_UCLAMP_TASK */
955 
956 /*
957  * This is the main, per-CPU runqueue data structure.
958  *
959  * Locking rule: those places that want to lock multiple runqueues
960  * (such as the load balancing or the thread migration code), lock
961  * acquire operations must be ordered by ascending &runqueue.
962  */
963 struct rq {
964 	/* runqueue lock: */
965 	raw_spinlock_t		__lock;
966 
967 	/*
968 	 * nr_running and cpu_load should be in the same cacheline because
969 	 * remote CPUs use both these fields when doing load calculation.
970 	 */
971 	unsigned int		nr_running;
972 #ifdef CONFIG_NUMA_BALANCING
973 	unsigned int		nr_numa_running;
974 	unsigned int		nr_preferred_running;
975 	unsigned int		numa_migrate_on;
976 #endif
977 #ifdef CONFIG_NO_HZ_COMMON
978 #ifdef CONFIG_SMP
979 	unsigned long		last_blocked_load_update_tick;
980 	unsigned int		has_blocked_load;
981 	call_single_data_t	nohz_csd;
982 #endif /* CONFIG_SMP */
983 	unsigned int		nohz_tick_stopped;
984 	atomic_t		nohz_flags;
985 #endif /* CONFIG_NO_HZ_COMMON */
986 
987 #ifdef CONFIG_SMP
988 	unsigned int		ttwu_pending;
989 #endif
990 	u64			nr_switches;
991 
992 #ifdef CONFIG_UCLAMP_TASK
993 	/* Utilization clamp values based on CPU's RUNNABLE tasks */
994 	struct uclamp_rq	uclamp[UCLAMP_CNT] ____cacheline_aligned;
995 	unsigned int		uclamp_flags;
996 #define UCLAMP_FLAG_IDLE 0x01
997 #endif
998 
999 	struct cfs_rq		cfs;
1000 	struct rt_rq		rt;
1001 	struct dl_rq		dl;
1002 
1003 #ifdef CONFIG_FAIR_GROUP_SCHED
1004 	/* list of leaf cfs_rq on this CPU: */
1005 	struct list_head	leaf_cfs_rq_list;
1006 	struct list_head	*tmp_alone_branch;
1007 #endif /* CONFIG_FAIR_GROUP_SCHED */
1008 
1009 	/*
1010 	 * This is part of a global counter where only the total sum
1011 	 * over all CPUs matters. A task can increase this counter on
1012 	 * one CPU and if it got migrated afterwards it may decrease
1013 	 * it on another CPU. Always updated under the runqueue lock:
1014 	 */
1015 	unsigned int		nr_uninterruptible;
1016 
1017 	struct task_struct __rcu	*curr;
1018 	struct task_struct	*idle;
1019 	struct task_struct	*stop;
1020 	unsigned long		next_balance;
1021 	struct mm_struct	*prev_mm;
1022 
1023 	unsigned int		clock_update_flags;
1024 	u64			clock;
1025 	/* Ensure that all clocks are in the same cache line */
1026 	u64			clock_task ____cacheline_aligned;
1027 	u64			clock_pelt;
1028 	unsigned long		lost_idle_time;
1029 	u64			clock_pelt_idle;
1030 	u64			clock_idle;
1031 #ifndef CONFIG_64BIT
1032 	u64			clock_pelt_idle_copy;
1033 	u64			clock_idle_copy;
1034 #endif
1035 
1036 	atomic_t		nr_iowait;
1037 
1038 #ifdef CONFIG_SCHED_DEBUG
1039 	u64 last_seen_need_resched_ns;
1040 	int ticks_without_resched;
1041 #endif
1042 
1043 #ifdef CONFIG_MEMBARRIER
1044 	int membarrier_state;
1045 #endif
1046 
1047 #ifdef CONFIG_SMP
1048 	struct root_domain		*rd;
1049 	struct sched_domain __rcu	*sd;
1050 
1051 	unsigned long		cpu_capacity;
1052 	unsigned long		cpu_capacity_orig;
1053 
1054 	struct callback_head	*balance_callback;
1055 
1056 	unsigned char		nohz_idle_balance;
1057 	unsigned char		idle_balance;
1058 
1059 	unsigned long		misfit_task_load;
1060 
1061 	/* For active balancing */
1062 	int			active_balance;
1063 	int			push_cpu;
1064 	struct cpu_stop_work	active_balance_work;
1065 
1066 	/* CPU of this runqueue: */
1067 	int			cpu;
1068 	int			online;
1069 
1070 	struct list_head cfs_tasks;
1071 
1072 	struct sched_avg	avg_rt;
1073 	struct sched_avg	avg_dl;
1074 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1075 	struct sched_avg	avg_irq;
1076 #endif
1077 #ifdef CONFIG_SCHED_THERMAL_PRESSURE
1078 	struct sched_avg	avg_thermal;
1079 #endif
1080 	u64			idle_stamp;
1081 	u64			avg_idle;
1082 
1083 	unsigned long		wake_stamp;
1084 	u64			wake_avg_idle;
1085 
1086 	/* This is used to determine avg_idle's max value */
1087 	u64			max_idle_balance_cost;
1088 
1089 #ifdef CONFIG_HOTPLUG_CPU
1090 	struct rcuwait		hotplug_wait;
1091 #endif
1092 #endif /* CONFIG_SMP */
1093 
1094 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1095 	u64			prev_irq_time;
1096 #endif
1097 #ifdef CONFIG_PARAVIRT
1098 	u64			prev_steal_time;
1099 #endif
1100 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1101 	u64			prev_steal_time_rq;
1102 #endif
1103 
1104 	/* calc_load related fields */
1105 	unsigned long		calc_load_update;
1106 	long			calc_load_active;
1107 
1108 #ifdef CONFIG_SCHED_HRTICK
1109 #ifdef CONFIG_SMP
1110 	call_single_data_t	hrtick_csd;
1111 #endif
1112 	struct hrtimer		hrtick_timer;
1113 	ktime_t 		hrtick_time;
1114 #endif
1115 
1116 #ifdef CONFIG_SCHEDSTATS
1117 	/* latency stats */
1118 	struct sched_info	rq_sched_info;
1119 	unsigned long long	rq_cpu_time;
1120 	/* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
1121 
1122 	/* sys_sched_yield() stats */
1123 	unsigned int		yld_count;
1124 
1125 	/* schedule() stats */
1126 	unsigned int		sched_count;
1127 	unsigned int		sched_goidle;
1128 
1129 	/* try_to_wake_up() stats */
1130 	unsigned int		ttwu_count;
1131 	unsigned int		ttwu_local;
1132 #endif
1133 
1134 #ifdef CONFIG_CPU_IDLE
1135 	/* Must be inspected within a rcu lock section */
1136 	struct cpuidle_state	*idle_state;
1137 #endif
1138 
1139 #ifdef CONFIG_SMP
1140 	unsigned int		nr_pinned;
1141 #endif
1142 	unsigned int		push_busy;
1143 	struct cpu_stop_work	push_work;
1144 
1145 #ifdef CONFIG_SCHED_CORE
1146 	/* per rq */
1147 	struct rq		*core;
1148 	struct task_struct	*core_pick;
1149 	unsigned int		core_enabled;
1150 	unsigned int		core_sched_seq;
1151 	struct rb_root		core_tree;
1152 
1153 	/* shared state -- careful with sched_core_cpu_deactivate() */
1154 	unsigned int		core_task_seq;
1155 	unsigned int		core_pick_seq;
1156 	unsigned long		core_cookie;
1157 	unsigned int		core_forceidle_count;
1158 	unsigned int		core_forceidle_seq;
1159 	unsigned int		core_forceidle_occupation;
1160 	u64			core_forceidle_start;
1161 #endif
1162 };
1163 
1164 #ifdef CONFIG_FAIR_GROUP_SCHED
1165 
1166 /* CPU runqueue to which this cfs_rq is attached */
1167 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1168 {
1169 	return cfs_rq->rq;
1170 }
1171 
1172 #else
1173 
1174 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1175 {
1176 	return container_of(cfs_rq, struct rq, cfs);
1177 }
1178 #endif
1179 
1180 static inline int cpu_of(struct rq *rq)
1181 {
1182 #ifdef CONFIG_SMP
1183 	return rq->cpu;
1184 #else
1185 	return 0;
1186 #endif
1187 }
1188 
1189 #define MDF_PUSH	0x01
1190 
1191 static inline bool is_migration_disabled(struct task_struct *p)
1192 {
1193 #ifdef CONFIG_SMP
1194 	return p->migration_disabled;
1195 #else
1196 	return false;
1197 #endif
1198 }
1199 
1200 struct sched_group;
1201 #ifdef CONFIG_SCHED_CORE
1202 static inline struct cpumask *sched_group_span(struct sched_group *sg);
1203 
1204 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled);
1205 
1206 static inline bool sched_core_enabled(struct rq *rq)
1207 {
1208 	return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled;
1209 }
1210 
1211 static inline bool sched_core_disabled(void)
1212 {
1213 	return !static_branch_unlikely(&__sched_core_enabled);
1214 }
1215 
1216 /*
1217  * Be careful with this function; not for general use. The return value isn't
1218  * stable unless you actually hold a relevant rq->__lock.
1219  */
1220 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1221 {
1222 	if (sched_core_enabled(rq))
1223 		return &rq->core->__lock;
1224 
1225 	return &rq->__lock;
1226 }
1227 
1228 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1229 {
1230 	if (rq->core_enabled)
1231 		return &rq->core->__lock;
1232 
1233 	return &rq->__lock;
1234 }
1235 
1236 bool cfs_prio_less(struct task_struct *a, struct task_struct *b, bool fi);
1237 
1238 /*
1239  * Helpers to check if the CPU's core cookie matches with the task's cookie
1240  * when core scheduling is enabled.
1241  * A special case is that the task's cookie always matches with CPU's core
1242  * cookie if the CPU is in an idle core.
1243  */
1244 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1245 {
1246 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1247 	if (!sched_core_enabled(rq))
1248 		return true;
1249 
1250 	return rq->core->core_cookie == p->core_cookie;
1251 }
1252 
1253 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1254 {
1255 	bool idle_core = true;
1256 	int cpu;
1257 
1258 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1259 	if (!sched_core_enabled(rq))
1260 		return true;
1261 
1262 	for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) {
1263 		if (!available_idle_cpu(cpu)) {
1264 			idle_core = false;
1265 			break;
1266 		}
1267 	}
1268 
1269 	/*
1270 	 * A CPU in an idle core is always the best choice for tasks with
1271 	 * cookies.
1272 	 */
1273 	return idle_core || rq->core->core_cookie == p->core_cookie;
1274 }
1275 
1276 static inline bool sched_group_cookie_match(struct rq *rq,
1277 					    struct task_struct *p,
1278 					    struct sched_group *group)
1279 {
1280 	int cpu;
1281 
1282 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1283 	if (!sched_core_enabled(rq))
1284 		return true;
1285 
1286 	for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
1287 		if (sched_core_cookie_match(rq, p))
1288 			return true;
1289 	}
1290 	return false;
1291 }
1292 
1293 static inline bool sched_core_enqueued(struct task_struct *p)
1294 {
1295 	return !RB_EMPTY_NODE(&p->core_node);
1296 }
1297 
1298 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p);
1299 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags);
1300 
1301 extern void sched_core_get(void);
1302 extern void sched_core_put(void);
1303 
1304 #else /* !CONFIG_SCHED_CORE */
1305 
1306 static inline bool sched_core_enabled(struct rq *rq)
1307 {
1308 	return false;
1309 }
1310 
1311 static inline bool sched_core_disabled(void)
1312 {
1313 	return true;
1314 }
1315 
1316 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1317 {
1318 	return &rq->__lock;
1319 }
1320 
1321 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1322 {
1323 	return &rq->__lock;
1324 }
1325 
1326 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1327 {
1328 	return true;
1329 }
1330 
1331 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1332 {
1333 	return true;
1334 }
1335 
1336 static inline bool sched_group_cookie_match(struct rq *rq,
1337 					    struct task_struct *p,
1338 					    struct sched_group *group)
1339 {
1340 	return true;
1341 }
1342 #endif /* CONFIG_SCHED_CORE */
1343 
1344 static inline void lockdep_assert_rq_held(struct rq *rq)
1345 {
1346 	lockdep_assert_held(__rq_lockp(rq));
1347 }
1348 
1349 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass);
1350 extern bool raw_spin_rq_trylock(struct rq *rq);
1351 extern void raw_spin_rq_unlock(struct rq *rq);
1352 
1353 static inline void raw_spin_rq_lock(struct rq *rq)
1354 {
1355 	raw_spin_rq_lock_nested(rq, 0);
1356 }
1357 
1358 static inline void raw_spin_rq_lock_irq(struct rq *rq)
1359 {
1360 	local_irq_disable();
1361 	raw_spin_rq_lock(rq);
1362 }
1363 
1364 static inline void raw_spin_rq_unlock_irq(struct rq *rq)
1365 {
1366 	raw_spin_rq_unlock(rq);
1367 	local_irq_enable();
1368 }
1369 
1370 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq)
1371 {
1372 	unsigned long flags;
1373 	local_irq_save(flags);
1374 	raw_spin_rq_lock(rq);
1375 	return flags;
1376 }
1377 
1378 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags)
1379 {
1380 	raw_spin_rq_unlock(rq);
1381 	local_irq_restore(flags);
1382 }
1383 
1384 #define raw_spin_rq_lock_irqsave(rq, flags)	\
1385 do {						\
1386 	flags = _raw_spin_rq_lock_irqsave(rq);	\
1387 } while (0)
1388 
1389 #ifdef CONFIG_SCHED_SMT
1390 extern void __update_idle_core(struct rq *rq);
1391 
1392 static inline void update_idle_core(struct rq *rq)
1393 {
1394 	if (static_branch_unlikely(&sched_smt_present))
1395 		__update_idle_core(rq);
1396 }
1397 
1398 #else
1399 static inline void update_idle_core(struct rq *rq) { }
1400 #endif
1401 
1402 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1403 
1404 #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
1405 #define this_rq()		this_cpu_ptr(&runqueues)
1406 #define task_rq(p)		cpu_rq(task_cpu(p))
1407 #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
1408 #define raw_rq()		raw_cpu_ptr(&runqueues)
1409 
1410 #ifdef CONFIG_FAIR_GROUP_SCHED
1411 static inline struct task_struct *task_of(struct sched_entity *se)
1412 {
1413 	SCHED_WARN_ON(!entity_is_task(se));
1414 	return container_of(se, struct task_struct, se);
1415 }
1416 
1417 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1418 {
1419 	return p->se.cfs_rq;
1420 }
1421 
1422 /* runqueue on which this entity is (to be) queued */
1423 static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se)
1424 {
1425 	return se->cfs_rq;
1426 }
1427 
1428 /* runqueue "owned" by this group */
1429 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1430 {
1431 	return grp->my_q;
1432 }
1433 
1434 #else
1435 
1436 static inline struct task_struct *task_of(struct sched_entity *se)
1437 {
1438 	return container_of(se, struct task_struct, se);
1439 }
1440 
1441 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1442 {
1443 	return &task_rq(p)->cfs;
1444 }
1445 
1446 static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se)
1447 {
1448 	struct task_struct *p = task_of(se);
1449 	struct rq *rq = task_rq(p);
1450 
1451 	return &rq->cfs;
1452 }
1453 
1454 /* runqueue "owned" by this group */
1455 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1456 {
1457 	return NULL;
1458 }
1459 #endif
1460 
1461 extern void update_rq_clock(struct rq *rq);
1462 
1463 /*
1464  * rq::clock_update_flags bits
1465  *
1466  * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1467  *  call to __schedule(). This is an optimisation to avoid
1468  *  neighbouring rq clock updates.
1469  *
1470  * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1471  *  in effect and calls to update_rq_clock() are being ignored.
1472  *
1473  * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1474  *  made to update_rq_clock() since the last time rq::lock was pinned.
1475  *
1476  * If inside of __schedule(), clock_update_flags will have been
1477  * shifted left (a left shift is a cheap operation for the fast path
1478  * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1479  *
1480  *	if (rq-clock_update_flags >= RQCF_UPDATED)
1481  *
1482  * to check if %RQCF_UPDATED is set. It'll never be shifted more than
1483  * one position though, because the next rq_unpin_lock() will shift it
1484  * back.
1485  */
1486 #define RQCF_REQ_SKIP		0x01
1487 #define RQCF_ACT_SKIP		0x02
1488 #define RQCF_UPDATED		0x04
1489 
1490 static inline void assert_clock_updated(struct rq *rq)
1491 {
1492 	/*
1493 	 * The only reason for not seeing a clock update since the
1494 	 * last rq_pin_lock() is if we're currently skipping updates.
1495 	 */
1496 	SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
1497 }
1498 
1499 static inline u64 rq_clock(struct rq *rq)
1500 {
1501 	lockdep_assert_rq_held(rq);
1502 	assert_clock_updated(rq);
1503 
1504 	return rq->clock;
1505 }
1506 
1507 static inline u64 rq_clock_task(struct rq *rq)
1508 {
1509 	lockdep_assert_rq_held(rq);
1510 	assert_clock_updated(rq);
1511 
1512 	return rq->clock_task;
1513 }
1514 
1515 /**
1516  * By default the decay is the default pelt decay period.
1517  * The decay shift can change the decay period in
1518  * multiples of 32.
1519  *  Decay shift		Decay period(ms)
1520  *	0			32
1521  *	1			64
1522  *	2			128
1523  *	3			256
1524  *	4			512
1525  */
1526 extern int sched_thermal_decay_shift;
1527 
1528 static inline u64 rq_clock_thermal(struct rq *rq)
1529 {
1530 	return rq_clock_task(rq) >> sched_thermal_decay_shift;
1531 }
1532 
1533 static inline void rq_clock_skip_update(struct rq *rq)
1534 {
1535 	lockdep_assert_rq_held(rq);
1536 	rq->clock_update_flags |= RQCF_REQ_SKIP;
1537 }
1538 
1539 /*
1540  * See rt task throttling, which is the only time a skip
1541  * request is canceled.
1542  */
1543 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1544 {
1545 	lockdep_assert_rq_held(rq);
1546 	rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1547 }
1548 
1549 struct rq_flags {
1550 	unsigned long flags;
1551 	struct pin_cookie cookie;
1552 #ifdef CONFIG_SCHED_DEBUG
1553 	/*
1554 	 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1555 	 * current pin context is stashed here in case it needs to be
1556 	 * restored in rq_repin_lock().
1557 	 */
1558 	unsigned int clock_update_flags;
1559 #endif
1560 };
1561 
1562 extern struct callback_head balance_push_callback;
1563 
1564 /*
1565  * Lockdep annotation that avoids accidental unlocks; it's like a
1566  * sticky/continuous lockdep_assert_held().
1567  *
1568  * This avoids code that has access to 'struct rq *rq' (basically everything in
1569  * the scheduler) from accidentally unlocking the rq if they do not also have a
1570  * copy of the (on-stack) 'struct rq_flags rf'.
1571  *
1572  * Also see Documentation/locking/lockdep-design.rst.
1573  */
1574 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1575 {
1576 	rf->cookie = lockdep_pin_lock(__rq_lockp(rq));
1577 
1578 #ifdef CONFIG_SCHED_DEBUG
1579 	rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1580 	rf->clock_update_flags = 0;
1581 #ifdef CONFIG_SMP
1582 	SCHED_WARN_ON(rq->balance_callback && rq->balance_callback != &balance_push_callback);
1583 #endif
1584 #endif
1585 }
1586 
1587 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1588 {
1589 #ifdef CONFIG_SCHED_DEBUG
1590 	if (rq->clock_update_flags > RQCF_ACT_SKIP)
1591 		rf->clock_update_flags = RQCF_UPDATED;
1592 #endif
1593 
1594 	lockdep_unpin_lock(__rq_lockp(rq), rf->cookie);
1595 }
1596 
1597 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1598 {
1599 	lockdep_repin_lock(__rq_lockp(rq), rf->cookie);
1600 
1601 #ifdef CONFIG_SCHED_DEBUG
1602 	/*
1603 	 * Restore the value we stashed in @rf for this pin context.
1604 	 */
1605 	rq->clock_update_flags |= rf->clock_update_flags;
1606 #endif
1607 }
1608 
1609 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1610 	__acquires(rq->lock);
1611 
1612 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1613 	__acquires(p->pi_lock)
1614 	__acquires(rq->lock);
1615 
1616 static inline void __task_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 void
1624 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1625 	__releases(rq->lock)
1626 	__releases(p->pi_lock)
1627 {
1628 	rq_unpin_lock(rq, rf);
1629 	raw_spin_rq_unlock(rq);
1630 	raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1631 }
1632 
1633 static inline void
1634 rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1635 	__acquires(rq->lock)
1636 {
1637 	raw_spin_rq_lock_irqsave(rq, rf->flags);
1638 	rq_pin_lock(rq, rf);
1639 }
1640 
1641 static inline void
1642 rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1643 	__acquires(rq->lock)
1644 {
1645 	raw_spin_rq_lock_irq(rq);
1646 	rq_pin_lock(rq, rf);
1647 }
1648 
1649 static inline void
1650 rq_lock(struct rq *rq, struct rq_flags *rf)
1651 	__acquires(rq->lock)
1652 {
1653 	raw_spin_rq_lock(rq);
1654 	rq_pin_lock(rq, rf);
1655 }
1656 
1657 static inline void
1658 rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1659 	__releases(rq->lock)
1660 {
1661 	rq_unpin_lock(rq, rf);
1662 	raw_spin_rq_unlock_irqrestore(rq, rf->flags);
1663 }
1664 
1665 static inline void
1666 rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1667 	__releases(rq->lock)
1668 {
1669 	rq_unpin_lock(rq, rf);
1670 	raw_spin_rq_unlock_irq(rq);
1671 }
1672 
1673 static inline void
1674 rq_unlock(struct rq *rq, struct rq_flags *rf)
1675 	__releases(rq->lock)
1676 {
1677 	rq_unpin_lock(rq, rf);
1678 	raw_spin_rq_unlock(rq);
1679 }
1680 
1681 static inline struct rq *
1682 this_rq_lock_irq(struct rq_flags *rf)
1683 	__acquires(rq->lock)
1684 {
1685 	struct rq *rq;
1686 
1687 	local_irq_disable();
1688 	rq = this_rq();
1689 	rq_lock(rq, rf);
1690 	return rq;
1691 }
1692 
1693 #ifdef CONFIG_NUMA
1694 enum numa_topology_type {
1695 	NUMA_DIRECT,
1696 	NUMA_GLUELESS_MESH,
1697 	NUMA_BACKPLANE,
1698 };
1699 extern enum numa_topology_type sched_numa_topology_type;
1700 extern int sched_max_numa_distance;
1701 extern bool find_numa_distance(int distance);
1702 extern void sched_init_numa(int offline_node);
1703 extern void sched_update_numa(int cpu, bool online);
1704 extern void sched_domains_numa_masks_set(unsigned int cpu);
1705 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1706 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1707 #else
1708 static inline void sched_init_numa(int offline_node) { }
1709 static inline void sched_update_numa(int cpu, bool online) { }
1710 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
1711 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1712 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1713 {
1714 	return nr_cpu_ids;
1715 }
1716 #endif
1717 
1718 #ifdef CONFIG_NUMA_BALANCING
1719 /* The regions in numa_faults array from task_struct */
1720 enum numa_faults_stats {
1721 	NUMA_MEM = 0,
1722 	NUMA_CPU,
1723 	NUMA_MEMBUF,
1724 	NUMA_CPUBUF
1725 };
1726 extern void sched_setnuma(struct task_struct *p, int node);
1727 extern int migrate_task_to(struct task_struct *p, int cpu);
1728 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1729 			int cpu, int scpu);
1730 extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1731 #else
1732 static inline void
1733 init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1734 {
1735 }
1736 #endif /* CONFIG_NUMA_BALANCING */
1737 
1738 #ifdef CONFIG_SMP
1739 
1740 static inline void
1741 queue_balance_callback(struct rq *rq,
1742 		       struct callback_head *head,
1743 		       void (*func)(struct rq *rq))
1744 {
1745 	lockdep_assert_rq_held(rq);
1746 
1747 	/*
1748 	 * Don't (re)queue an already queued item; nor queue anything when
1749 	 * balance_push() is active, see the comment with
1750 	 * balance_push_callback.
1751 	 */
1752 	if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
1753 		return;
1754 
1755 	head->func = (void (*)(struct callback_head *))func;
1756 	head->next = rq->balance_callback;
1757 	rq->balance_callback = head;
1758 }
1759 
1760 #define rcu_dereference_check_sched_domain(p) \
1761 	rcu_dereference_check((p), \
1762 			      lockdep_is_held(&sched_domains_mutex))
1763 
1764 /*
1765  * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1766  * See destroy_sched_domains: call_rcu for details.
1767  *
1768  * The domain tree of any CPU may only be accessed from within
1769  * preempt-disabled sections.
1770  */
1771 #define for_each_domain(cpu, __sd) \
1772 	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1773 			__sd; __sd = __sd->parent)
1774 
1775 /**
1776  * highest_flag_domain - Return highest sched_domain containing flag.
1777  * @cpu:	The CPU whose highest level of sched domain is to
1778  *		be returned.
1779  * @flag:	The flag to check for the highest sched_domain
1780  *		for the given CPU.
1781  *
1782  * Returns the highest sched_domain of a CPU which contains the given flag.
1783  */
1784 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1785 {
1786 	struct sched_domain *sd, *hsd = NULL;
1787 
1788 	for_each_domain(cpu, sd) {
1789 		if (!(sd->flags & flag))
1790 			break;
1791 		hsd = sd;
1792 	}
1793 
1794 	return hsd;
1795 }
1796 
1797 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1798 {
1799 	struct sched_domain *sd;
1800 
1801 	for_each_domain(cpu, sd) {
1802 		if (sd->flags & flag)
1803 			break;
1804 	}
1805 
1806 	return sd;
1807 }
1808 
1809 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
1810 DECLARE_PER_CPU(int, sd_llc_size);
1811 DECLARE_PER_CPU(int, sd_llc_id);
1812 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
1813 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
1814 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
1815 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
1816 extern struct static_key_false sched_asym_cpucapacity;
1817 
1818 struct sched_group_capacity {
1819 	atomic_t		ref;
1820 	/*
1821 	 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
1822 	 * for a single CPU.
1823 	 */
1824 	unsigned long		capacity;
1825 	unsigned long		min_capacity;		/* Min per-CPU capacity in group */
1826 	unsigned long		max_capacity;		/* Max per-CPU capacity in group */
1827 	unsigned long		next_update;
1828 	int			imbalance;		/* XXX unrelated to capacity but shared group state */
1829 
1830 #ifdef CONFIG_SCHED_DEBUG
1831 	int			id;
1832 #endif
1833 
1834 	unsigned long		cpumask[];		/* Balance mask */
1835 };
1836 
1837 struct sched_group {
1838 	struct sched_group	*next;			/* Must be a circular list */
1839 	atomic_t		ref;
1840 
1841 	unsigned int		group_weight;
1842 	struct sched_group_capacity *sgc;
1843 	int			asym_prefer_cpu;	/* CPU of highest priority in group */
1844 	int			flags;
1845 
1846 	/*
1847 	 * The CPUs this group covers.
1848 	 *
1849 	 * NOTE: this field is variable length. (Allocated dynamically
1850 	 * by attaching extra space to the end of the structure,
1851 	 * depending on how many CPUs the kernel has booted up with)
1852 	 */
1853 	unsigned long		cpumask[];
1854 };
1855 
1856 static inline struct cpumask *sched_group_span(struct sched_group *sg)
1857 {
1858 	return to_cpumask(sg->cpumask);
1859 }
1860 
1861 /*
1862  * See build_balance_mask().
1863  */
1864 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
1865 {
1866 	return to_cpumask(sg->sgc->cpumask);
1867 }
1868 
1869 extern int group_balance_cpu(struct sched_group *sg);
1870 
1871 #ifdef CONFIG_SCHED_DEBUG
1872 void update_sched_domain_debugfs(void);
1873 void dirty_sched_domain_sysctl(int cpu);
1874 #else
1875 static inline void update_sched_domain_debugfs(void)
1876 {
1877 }
1878 static inline void dirty_sched_domain_sysctl(int cpu)
1879 {
1880 }
1881 #endif
1882 
1883 extern int sched_update_scaling(void);
1884 #endif /* CONFIG_SMP */
1885 
1886 #include "stats.h"
1887 
1888 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS)
1889 
1890 extern void __sched_core_account_forceidle(struct rq *rq);
1891 
1892 static inline void sched_core_account_forceidle(struct rq *rq)
1893 {
1894 	if (schedstat_enabled())
1895 		__sched_core_account_forceidle(rq);
1896 }
1897 
1898 extern void __sched_core_tick(struct rq *rq);
1899 
1900 static inline void sched_core_tick(struct rq *rq)
1901 {
1902 	if (sched_core_enabled(rq) && schedstat_enabled())
1903 		__sched_core_tick(rq);
1904 }
1905 
1906 #else
1907 
1908 static inline void sched_core_account_forceidle(struct rq *rq) {}
1909 
1910 static inline void sched_core_tick(struct rq *rq) {}
1911 
1912 #endif /* CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS */
1913 
1914 #ifdef CONFIG_CGROUP_SCHED
1915 
1916 /*
1917  * Return the group to which this tasks belongs.
1918  *
1919  * We cannot use task_css() and friends because the cgroup subsystem
1920  * changes that value before the cgroup_subsys::attach() method is called,
1921  * therefore we cannot pin it and might observe the wrong value.
1922  *
1923  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
1924  * core changes this before calling sched_move_task().
1925  *
1926  * Instead we use a 'copy' which is updated from sched_move_task() while
1927  * holding both task_struct::pi_lock and rq::lock.
1928  */
1929 static inline struct task_group *task_group(struct task_struct *p)
1930 {
1931 	return p->sched_task_group;
1932 }
1933 
1934 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
1935 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
1936 {
1937 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
1938 	struct task_group *tg = task_group(p);
1939 #endif
1940 
1941 #ifdef CONFIG_FAIR_GROUP_SCHED
1942 	set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
1943 	p->se.cfs_rq = tg->cfs_rq[cpu];
1944 	p->se.parent = tg->se[cpu];
1945 #endif
1946 
1947 #ifdef CONFIG_RT_GROUP_SCHED
1948 	p->rt.rt_rq  = tg->rt_rq[cpu];
1949 	p->rt.parent = tg->rt_se[cpu];
1950 #endif
1951 }
1952 
1953 #else /* CONFIG_CGROUP_SCHED */
1954 
1955 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
1956 static inline struct task_group *task_group(struct task_struct *p)
1957 {
1958 	return NULL;
1959 }
1960 
1961 #endif /* CONFIG_CGROUP_SCHED */
1962 
1963 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
1964 {
1965 	set_task_rq(p, cpu);
1966 #ifdef CONFIG_SMP
1967 	/*
1968 	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
1969 	 * successfully executed on another CPU. We must ensure that updates of
1970 	 * per-task data have been completed by this moment.
1971 	 */
1972 	smp_wmb();
1973 	WRITE_ONCE(task_thread_info(p)->cpu, cpu);
1974 	p->wake_cpu = cpu;
1975 #endif
1976 }
1977 
1978 /*
1979  * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
1980  */
1981 #ifdef CONFIG_SCHED_DEBUG
1982 # define const_debug __read_mostly
1983 #else
1984 # define const_debug const
1985 #endif
1986 
1987 #define SCHED_FEAT(name, enabled)	\
1988 	__SCHED_FEAT_##name ,
1989 
1990 enum {
1991 #include "features.h"
1992 	__SCHED_FEAT_NR,
1993 };
1994 
1995 #undef SCHED_FEAT
1996 
1997 #ifdef CONFIG_SCHED_DEBUG
1998 
1999 /*
2000  * To support run-time toggling of sched features, all the translation units
2001  * (but core.c) reference the sysctl_sched_features defined in core.c.
2002  */
2003 extern const_debug unsigned int sysctl_sched_features;
2004 
2005 #ifdef CONFIG_JUMP_LABEL
2006 #define SCHED_FEAT(name, enabled)					\
2007 static __always_inline bool static_branch_##name(struct static_key *key) \
2008 {									\
2009 	return static_key_##enabled(key);				\
2010 }
2011 
2012 #include "features.h"
2013 #undef SCHED_FEAT
2014 
2015 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
2016 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
2017 
2018 #else /* !CONFIG_JUMP_LABEL */
2019 
2020 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2021 
2022 #endif /* CONFIG_JUMP_LABEL */
2023 
2024 #else /* !SCHED_DEBUG */
2025 
2026 /*
2027  * Each translation unit has its own copy of sysctl_sched_features to allow
2028  * constants propagation at compile time and compiler optimization based on
2029  * features default.
2030  */
2031 #define SCHED_FEAT(name, enabled)	\
2032 	(1UL << __SCHED_FEAT_##name) * enabled |
2033 static const_debug __maybe_unused unsigned int sysctl_sched_features =
2034 #include "features.h"
2035 	0;
2036 #undef SCHED_FEAT
2037 
2038 #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2039 
2040 #endif /* SCHED_DEBUG */
2041 
2042 extern struct static_key_false sched_numa_balancing;
2043 extern struct static_key_false sched_schedstats;
2044 
2045 static inline u64 global_rt_period(void)
2046 {
2047 	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
2048 }
2049 
2050 static inline u64 global_rt_runtime(void)
2051 {
2052 	if (sysctl_sched_rt_runtime < 0)
2053 		return RUNTIME_INF;
2054 
2055 	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
2056 }
2057 
2058 static inline int task_current(struct rq *rq, struct task_struct *p)
2059 {
2060 	return rq->curr == p;
2061 }
2062 
2063 static inline int task_running(struct rq *rq, struct task_struct *p)
2064 {
2065 #ifdef CONFIG_SMP
2066 	return p->on_cpu;
2067 #else
2068 	return task_current(rq, p);
2069 #endif
2070 }
2071 
2072 static inline int task_on_rq_queued(struct task_struct *p)
2073 {
2074 	return p->on_rq == TASK_ON_RQ_QUEUED;
2075 }
2076 
2077 static inline int task_on_rq_migrating(struct task_struct *p)
2078 {
2079 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
2080 }
2081 
2082 /* Wake flags. The first three directly map to some SD flag value */
2083 #define WF_EXEC     0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
2084 #define WF_FORK     0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
2085 #define WF_TTWU     0x08 /* Wakeup;            maps to SD_BALANCE_WAKE */
2086 
2087 #define WF_SYNC     0x10 /* Waker goes to sleep after wakeup */
2088 #define WF_MIGRATED 0x20 /* Internal use, task got migrated */
2089 
2090 #ifdef CONFIG_SMP
2091 static_assert(WF_EXEC == SD_BALANCE_EXEC);
2092 static_assert(WF_FORK == SD_BALANCE_FORK);
2093 static_assert(WF_TTWU == SD_BALANCE_WAKE);
2094 #endif
2095 
2096 /*
2097  * To aid in avoiding the subversion of "niceness" due to uneven distribution
2098  * of tasks with abnormal "nice" values across CPUs the contribution that
2099  * each task makes to its run queue's load is weighted according to its
2100  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
2101  * scaled version of the new time slice allocation that they receive on time
2102  * slice expiry etc.
2103  */
2104 
2105 #define WEIGHT_IDLEPRIO		3
2106 #define WMULT_IDLEPRIO		1431655765
2107 
2108 extern const int		sched_prio_to_weight[40];
2109 extern const u32		sched_prio_to_wmult[40];
2110 
2111 /*
2112  * {de,en}queue flags:
2113  *
2114  * DEQUEUE_SLEEP  - task is no longer runnable
2115  * ENQUEUE_WAKEUP - task just became runnable
2116  *
2117  * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
2118  *                are in a known state which allows modification. Such pairs
2119  *                should preserve as much state as possible.
2120  *
2121  * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
2122  *        in the runqueue.
2123  *
2124  * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
2125  * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
2126  * ENQUEUE_MIGRATED  - the task was migrated during wakeup
2127  *
2128  */
2129 
2130 #define DEQUEUE_SLEEP		0x01
2131 #define DEQUEUE_SAVE		0x02 /* Matches ENQUEUE_RESTORE */
2132 #define DEQUEUE_MOVE		0x04 /* Matches ENQUEUE_MOVE */
2133 #define DEQUEUE_NOCLOCK		0x08 /* Matches ENQUEUE_NOCLOCK */
2134 
2135 #define ENQUEUE_WAKEUP		0x01
2136 #define ENQUEUE_RESTORE		0x02
2137 #define ENQUEUE_MOVE		0x04
2138 #define ENQUEUE_NOCLOCK		0x08
2139 
2140 #define ENQUEUE_HEAD		0x10
2141 #define ENQUEUE_REPLENISH	0x20
2142 #ifdef CONFIG_SMP
2143 #define ENQUEUE_MIGRATED	0x40
2144 #else
2145 #define ENQUEUE_MIGRATED	0x00
2146 #endif
2147 
2148 #define RETRY_TASK		((void *)-1UL)
2149 
2150 struct sched_class {
2151 
2152 #ifdef CONFIG_UCLAMP_TASK
2153 	int uclamp_enabled;
2154 #endif
2155 
2156 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
2157 	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
2158 	void (*yield_task)   (struct rq *rq);
2159 	bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
2160 
2161 	void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags);
2162 
2163 	struct task_struct *(*pick_next_task)(struct rq *rq);
2164 
2165 	void (*put_prev_task)(struct rq *rq, struct task_struct *p);
2166 	void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
2167 
2168 #ifdef CONFIG_SMP
2169 	int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2170 	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
2171 
2172 	struct task_struct * (*pick_task)(struct rq *rq);
2173 
2174 	void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
2175 
2176 	void (*task_woken)(struct rq *this_rq, struct task_struct *task);
2177 
2178 	void (*set_cpus_allowed)(struct task_struct *p,
2179 				 const struct cpumask *newmask,
2180 				 u32 flags);
2181 
2182 	void (*rq_online)(struct rq *rq);
2183 	void (*rq_offline)(struct rq *rq);
2184 
2185 	struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
2186 #endif
2187 
2188 	void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
2189 	void (*task_fork)(struct task_struct *p);
2190 	void (*task_dead)(struct task_struct *p);
2191 
2192 	/*
2193 	 * The switched_from() call is allowed to drop rq->lock, therefore we
2194 	 * cannot assume the switched_from/switched_to pair is serialized by
2195 	 * rq->lock. They are however serialized by p->pi_lock.
2196 	 */
2197 	void (*switched_from)(struct rq *this_rq, struct task_struct *task);
2198 	void (*switched_to)  (struct rq *this_rq, struct task_struct *task);
2199 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
2200 			      int oldprio);
2201 
2202 	unsigned int (*get_rr_interval)(struct rq *rq,
2203 					struct task_struct *task);
2204 
2205 	void (*update_curr)(struct rq *rq);
2206 
2207 #define TASK_SET_GROUP		0
2208 #define TASK_MOVE_GROUP		1
2209 
2210 #ifdef CONFIG_FAIR_GROUP_SCHED
2211 	void (*task_change_group)(struct task_struct *p, int type);
2212 #endif
2213 };
2214 
2215 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
2216 {
2217 	WARN_ON_ONCE(rq->curr != prev);
2218 	prev->sched_class->put_prev_task(rq, prev);
2219 }
2220 
2221 static inline void set_next_task(struct rq *rq, struct task_struct *next)
2222 {
2223 	next->sched_class->set_next_task(rq, next, false);
2224 }
2225 
2226 
2227 /*
2228  * Helper to define a sched_class instance; each one is placed in a separate
2229  * section which is ordered by the linker script:
2230  *
2231  *   include/asm-generic/vmlinux.lds.h
2232  *
2233  * *CAREFUL* they are laid out in *REVERSE* order!!!
2234  *
2235  * Also enforce alignment on the instance, not the type, to guarantee layout.
2236  */
2237 #define DEFINE_SCHED_CLASS(name) \
2238 const struct sched_class name##_sched_class \
2239 	__aligned(__alignof__(struct sched_class)) \
2240 	__section("__" #name "_sched_class")
2241 
2242 /* Defined in include/asm-generic/vmlinux.lds.h */
2243 extern struct sched_class __sched_class_highest[];
2244 extern struct sched_class __sched_class_lowest[];
2245 
2246 #define for_class_range(class, _from, _to) \
2247 	for (class = (_from); class < (_to); class++)
2248 
2249 #define for_each_class(class) \
2250 	for_class_range(class, __sched_class_highest, __sched_class_lowest)
2251 
2252 #define sched_class_above(_a, _b)	((_a) < (_b))
2253 
2254 extern const struct sched_class stop_sched_class;
2255 extern const struct sched_class dl_sched_class;
2256 extern const struct sched_class rt_sched_class;
2257 extern const struct sched_class fair_sched_class;
2258 extern const struct sched_class idle_sched_class;
2259 
2260 static inline bool sched_stop_runnable(struct rq *rq)
2261 {
2262 	return rq->stop && task_on_rq_queued(rq->stop);
2263 }
2264 
2265 static inline bool sched_dl_runnable(struct rq *rq)
2266 {
2267 	return rq->dl.dl_nr_running > 0;
2268 }
2269 
2270 static inline bool sched_rt_runnable(struct rq *rq)
2271 {
2272 	return rq->rt.rt_queued > 0;
2273 }
2274 
2275 static inline bool sched_fair_runnable(struct rq *rq)
2276 {
2277 	return rq->cfs.nr_running > 0;
2278 }
2279 
2280 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2281 extern struct task_struct *pick_next_task_idle(struct rq *rq);
2282 
2283 #define SCA_CHECK		0x01
2284 #define SCA_MIGRATE_DISABLE	0x02
2285 #define SCA_MIGRATE_ENABLE	0x04
2286 #define SCA_USER		0x08
2287 
2288 #ifdef CONFIG_SMP
2289 
2290 extern void update_group_capacity(struct sched_domain *sd, int cpu);
2291 
2292 extern void trigger_load_balance(struct rq *rq);
2293 
2294 extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask, u32 flags);
2295 
2296 static inline struct task_struct *get_push_task(struct rq *rq)
2297 {
2298 	struct task_struct *p = rq->curr;
2299 
2300 	lockdep_assert_rq_held(rq);
2301 
2302 	if (rq->push_busy)
2303 		return NULL;
2304 
2305 	if (p->nr_cpus_allowed == 1)
2306 		return NULL;
2307 
2308 	if (p->migration_disabled)
2309 		return NULL;
2310 
2311 	rq->push_busy = true;
2312 	return get_task_struct(p);
2313 }
2314 
2315 extern int push_cpu_stop(void *arg);
2316 
2317 #endif
2318 
2319 #ifdef CONFIG_CPU_IDLE
2320 static inline void idle_set_state(struct rq *rq,
2321 				  struct cpuidle_state *idle_state)
2322 {
2323 	rq->idle_state = idle_state;
2324 }
2325 
2326 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2327 {
2328 	SCHED_WARN_ON(!rcu_read_lock_held());
2329 
2330 	return rq->idle_state;
2331 }
2332 #else
2333 static inline void idle_set_state(struct rq *rq,
2334 				  struct cpuidle_state *idle_state)
2335 {
2336 }
2337 
2338 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2339 {
2340 	return NULL;
2341 }
2342 #endif
2343 
2344 extern void schedule_idle(void);
2345 
2346 extern void sysrq_sched_debug_show(void);
2347 extern void sched_init_granularity(void);
2348 extern void update_max_interval(void);
2349 
2350 extern void init_sched_dl_class(void);
2351 extern void init_sched_rt_class(void);
2352 extern void init_sched_fair_class(void);
2353 
2354 extern void reweight_task(struct task_struct *p, int prio);
2355 
2356 extern void resched_curr(struct rq *rq);
2357 extern void resched_cpu(int cpu);
2358 
2359 extern struct rt_bandwidth def_rt_bandwidth;
2360 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
2361 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq);
2362 
2363 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
2364 extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
2365 extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se);
2366 
2367 #define BW_SHIFT		20
2368 #define BW_UNIT			(1 << BW_SHIFT)
2369 #define RATIO_SHIFT		8
2370 #define MAX_BW_BITS		(64 - BW_SHIFT)
2371 #define MAX_BW			((1ULL << MAX_BW_BITS) - 1)
2372 unsigned long to_ratio(u64 period, u64 runtime);
2373 
2374 extern void init_entity_runnable_average(struct sched_entity *se);
2375 extern void post_init_entity_util_avg(struct task_struct *p);
2376 
2377 #ifdef CONFIG_NO_HZ_FULL
2378 extern bool sched_can_stop_tick(struct rq *rq);
2379 extern int __init sched_tick_offload_init(void);
2380 
2381 /*
2382  * Tick may be needed by tasks in the runqueue depending on their policy and
2383  * requirements. If tick is needed, lets send the target an IPI to kick it out of
2384  * nohz mode if necessary.
2385  */
2386 static inline void sched_update_tick_dependency(struct rq *rq)
2387 {
2388 	int cpu = cpu_of(rq);
2389 
2390 	if (!tick_nohz_full_cpu(cpu))
2391 		return;
2392 
2393 	if (sched_can_stop_tick(rq))
2394 		tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
2395 	else
2396 		tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
2397 }
2398 #else
2399 static inline int sched_tick_offload_init(void) { return 0; }
2400 static inline void sched_update_tick_dependency(struct rq *rq) { }
2401 #endif
2402 
2403 static inline void add_nr_running(struct rq *rq, unsigned count)
2404 {
2405 	unsigned prev_nr = rq->nr_running;
2406 
2407 	rq->nr_running = prev_nr + count;
2408 	if (trace_sched_update_nr_running_tp_enabled()) {
2409 		call_trace_sched_update_nr_running(rq, count);
2410 	}
2411 
2412 #ifdef CONFIG_SMP
2413 	if (prev_nr < 2 && rq->nr_running >= 2) {
2414 		if (!READ_ONCE(rq->rd->overload))
2415 			WRITE_ONCE(rq->rd->overload, 1);
2416 	}
2417 #endif
2418 
2419 	sched_update_tick_dependency(rq);
2420 }
2421 
2422 static inline void sub_nr_running(struct rq *rq, unsigned count)
2423 {
2424 	rq->nr_running -= count;
2425 	if (trace_sched_update_nr_running_tp_enabled()) {
2426 		call_trace_sched_update_nr_running(rq, -count);
2427 	}
2428 
2429 	/* Check if we still need preemption */
2430 	sched_update_tick_dependency(rq);
2431 }
2432 
2433 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
2434 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
2435 
2436 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
2437 
2438 extern const_debug unsigned int sysctl_sched_nr_migrate;
2439 extern const_debug unsigned int sysctl_sched_migration_cost;
2440 
2441 #ifdef CONFIG_SCHED_DEBUG
2442 extern unsigned int sysctl_sched_latency;
2443 extern unsigned int sysctl_sched_min_granularity;
2444 extern unsigned int sysctl_sched_idle_min_granularity;
2445 extern unsigned int sysctl_sched_wakeup_granularity;
2446 extern int sysctl_resched_latency_warn_ms;
2447 extern int sysctl_resched_latency_warn_once;
2448 
2449 extern unsigned int sysctl_sched_tunable_scaling;
2450 
2451 extern unsigned int sysctl_numa_balancing_scan_delay;
2452 extern unsigned int sysctl_numa_balancing_scan_period_min;
2453 extern unsigned int sysctl_numa_balancing_scan_period_max;
2454 extern unsigned int sysctl_numa_balancing_scan_size;
2455 #endif
2456 
2457 #ifdef CONFIG_SCHED_HRTICK
2458 
2459 /*
2460  * Use hrtick when:
2461  *  - enabled by features
2462  *  - hrtimer is actually high res
2463  */
2464 static inline int hrtick_enabled(struct rq *rq)
2465 {
2466 	if (!cpu_active(cpu_of(rq)))
2467 		return 0;
2468 	return hrtimer_is_hres_active(&rq->hrtick_timer);
2469 }
2470 
2471 static inline int hrtick_enabled_fair(struct rq *rq)
2472 {
2473 	if (!sched_feat(HRTICK))
2474 		return 0;
2475 	return hrtick_enabled(rq);
2476 }
2477 
2478 static inline int hrtick_enabled_dl(struct rq *rq)
2479 {
2480 	if (!sched_feat(HRTICK_DL))
2481 		return 0;
2482 	return hrtick_enabled(rq);
2483 }
2484 
2485 void hrtick_start(struct rq *rq, u64 delay);
2486 
2487 #else
2488 
2489 static inline int hrtick_enabled_fair(struct rq *rq)
2490 {
2491 	return 0;
2492 }
2493 
2494 static inline int hrtick_enabled_dl(struct rq *rq)
2495 {
2496 	return 0;
2497 }
2498 
2499 static inline int hrtick_enabled(struct rq *rq)
2500 {
2501 	return 0;
2502 }
2503 
2504 #endif /* CONFIG_SCHED_HRTICK */
2505 
2506 #ifndef arch_scale_freq_tick
2507 static __always_inline
2508 void arch_scale_freq_tick(void)
2509 {
2510 }
2511 #endif
2512 
2513 #ifndef arch_scale_freq_capacity
2514 /**
2515  * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
2516  * @cpu: the CPU in question.
2517  *
2518  * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
2519  *
2520  *     f_curr
2521  *     ------ * SCHED_CAPACITY_SCALE
2522  *     f_max
2523  */
2524 static __always_inline
2525 unsigned long arch_scale_freq_capacity(int cpu)
2526 {
2527 	return SCHED_CAPACITY_SCALE;
2528 }
2529 #endif
2530 
2531 #ifdef CONFIG_SCHED_DEBUG
2532 /*
2533  * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to
2534  * acquire rq lock instead of rq_lock(). So at the end of these two functions
2535  * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of
2536  * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning.
2537  */
2538 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2)
2539 {
2540 	rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
2541 	/* rq1 == rq2 for !CONFIG_SMP, so just clear RQCF_UPDATED once. */
2542 #ifdef CONFIG_SMP
2543 	rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
2544 #endif
2545 }
2546 #else
2547 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2) {}
2548 #endif
2549 
2550 #ifdef CONFIG_SMP
2551 
2552 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2)
2553 {
2554 #ifdef CONFIG_SCHED_CORE
2555 	/*
2556 	 * In order to not have {0,2},{1,3} turn into into an AB-BA,
2557 	 * order by core-id first and cpu-id second.
2558 	 *
2559 	 * Notably:
2560 	 *
2561 	 *	double_rq_lock(0,3); will take core-0, core-1 lock
2562 	 *	double_rq_lock(1,2); will take core-1, core-0 lock
2563 	 *
2564 	 * when only cpu-id is considered.
2565 	 */
2566 	if (rq1->core->cpu < rq2->core->cpu)
2567 		return true;
2568 	if (rq1->core->cpu > rq2->core->cpu)
2569 		return false;
2570 
2571 	/*
2572 	 * __sched_core_flip() relies on SMT having cpu-id lock order.
2573 	 */
2574 #endif
2575 	return rq1->cpu < rq2->cpu;
2576 }
2577 
2578 extern void double_rq_lock(struct rq *rq1, struct rq *rq2);
2579 
2580 #ifdef CONFIG_PREEMPTION
2581 
2582 /*
2583  * fair double_lock_balance: Safely acquires both rq->locks in a fair
2584  * way at the expense of forcing extra atomic operations in all
2585  * invocations.  This assures that the double_lock is acquired using the
2586  * same underlying policy as the spinlock_t on this architecture, which
2587  * reduces latency compared to the unfair variant below.  However, it
2588  * also adds more overhead and therefore may reduce throughput.
2589  */
2590 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2591 	__releases(this_rq->lock)
2592 	__acquires(busiest->lock)
2593 	__acquires(this_rq->lock)
2594 {
2595 	raw_spin_rq_unlock(this_rq);
2596 	double_rq_lock(this_rq, busiest);
2597 
2598 	return 1;
2599 }
2600 
2601 #else
2602 /*
2603  * Unfair double_lock_balance: Optimizes throughput at the expense of
2604  * latency by eliminating extra atomic operations when the locks are
2605  * already in proper order on entry.  This favors lower CPU-ids and will
2606  * grant the double lock to lower CPUs over higher ids under contention,
2607  * regardless of entry order into the function.
2608  */
2609 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2610 	__releases(this_rq->lock)
2611 	__acquires(busiest->lock)
2612 	__acquires(this_rq->lock)
2613 {
2614 	if (__rq_lockp(this_rq) == __rq_lockp(busiest) ||
2615 	    likely(raw_spin_rq_trylock(busiest))) {
2616 		double_rq_clock_clear_update(this_rq, busiest);
2617 		return 0;
2618 	}
2619 
2620 	if (rq_order_less(this_rq, busiest)) {
2621 		raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING);
2622 		double_rq_clock_clear_update(this_rq, busiest);
2623 		return 0;
2624 	}
2625 
2626 	raw_spin_rq_unlock(this_rq);
2627 	double_rq_lock(this_rq, busiest);
2628 
2629 	return 1;
2630 }
2631 
2632 #endif /* CONFIG_PREEMPTION */
2633 
2634 /*
2635  * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
2636  */
2637 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
2638 {
2639 	lockdep_assert_irqs_disabled();
2640 
2641 	return _double_lock_balance(this_rq, busiest);
2642 }
2643 
2644 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
2645 	__releases(busiest->lock)
2646 {
2647 	if (__rq_lockp(this_rq) != __rq_lockp(busiest))
2648 		raw_spin_rq_unlock(busiest);
2649 	lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_);
2650 }
2651 
2652 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
2653 {
2654 	if (l1 > l2)
2655 		swap(l1, l2);
2656 
2657 	spin_lock(l1);
2658 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2659 }
2660 
2661 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
2662 {
2663 	if (l1 > l2)
2664 		swap(l1, l2);
2665 
2666 	spin_lock_irq(l1);
2667 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2668 }
2669 
2670 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
2671 {
2672 	if (l1 > l2)
2673 		swap(l1, l2);
2674 
2675 	raw_spin_lock(l1);
2676 	raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2677 }
2678 
2679 /*
2680  * double_rq_unlock - safely unlock two runqueues
2681  *
2682  * Note this does not restore interrupts like task_rq_unlock,
2683  * you need to do so manually after calling.
2684  */
2685 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2686 	__releases(rq1->lock)
2687 	__releases(rq2->lock)
2688 {
2689 	if (__rq_lockp(rq1) != __rq_lockp(rq2))
2690 		raw_spin_rq_unlock(rq2);
2691 	else
2692 		__release(rq2->lock);
2693 	raw_spin_rq_unlock(rq1);
2694 }
2695 
2696 extern void set_rq_online (struct rq *rq);
2697 extern void set_rq_offline(struct rq *rq);
2698 extern bool sched_smp_initialized;
2699 
2700 #else /* CONFIG_SMP */
2701 
2702 /*
2703  * double_rq_lock - safely lock two runqueues
2704  *
2705  * Note this does not disable interrupts like task_rq_lock,
2706  * you need to do so manually before calling.
2707  */
2708 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2709 	__acquires(rq1->lock)
2710 	__acquires(rq2->lock)
2711 {
2712 	BUG_ON(!irqs_disabled());
2713 	BUG_ON(rq1 != rq2);
2714 	raw_spin_rq_lock(rq1);
2715 	__acquire(rq2->lock);	/* Fake it out ;) */
2716 	double_rq_clock_clear_update(rq1, rq2);
2717 }
2718 
2719 /*
2720  * double_rq_unlock - safely unlock two runqueues
2721  *
2722  * Note this does not restore interrupts like task_rq_unlock,
2723  * you need to do so manually after calling.
2724  */
2725 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2726 	__releases(rq1->lock)
2727 	__releases(rq2->lock)
2728 {
2729 	BUG_ON(rq1 != rq2);
2730 	raw_spin_rq_unlock(rq1);
2731 	__release(rq2->lock);
2732 }
2733 
2734 #endif
2735 
2736 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
2737 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
2738 
2739 #ifdef	CONFIG_SCHED_DEBUG
2740 extern bool sched_debug_verbose;
2741 
2742 extern void print_cfs_stats(struct seq_file *m, int cpu);
2743 extern void print_rt_stats(struct seq_file *m, int cpu);
2744 extern void print_dl_stats(struct seq_file *m, int cpu);
2745 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
2746 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
2747 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
2748 
2749 extern void resched_latency_warn(int cpu, u64 latency);
2750 #ifdef CONFIG_NUMA_BALANCING
2751 extern void
2752 show_numa_stats(struct task_struct *p, struct seq_file *m);
2753 extern void
2754 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
2755 	unsigned long tpf, unsigned long gsf, unsigned long gpf);
2756 #endif /* CONFIG_NUMA_BALANCING */
2757 #else
2758 static inline void resched_latency_warn(int cpu, u64 latency) {}
2759 #endif /* CONFIG_SCHED_DEBUG */
2760 
2761 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
2762 extern void init_rt_rq(struct rt_rq *rt_rq);
2763 extern void init_dl_rq(struct dl_rq *dl_rq);
2764 
2765 extern void cfs_bandwidth_usage_inc(void);
2766 extern void cfs_bandwidth_usage_dec(void);
2767 
2768 #ifdef CONFIG_NO_HZ_COMMON
2769 #define NOHZ_BALANCE_KICK_BIT	0
2770 #define NOHZ_STATS_KICK_BIT	1
2771 #define NOHZ_NEWILB_KICK_BIT	2
2772 #define NOHZ_NEXT_KICK_BIT	3
2773 
2774 /* Run rebalance_domains() */
2775 #define NOHZ_BALANCE_KICK	BIT(NOHZ_BALANCE_KICK_BIT)
2776 /* Update blocked load */
2777 #define NOHZ_STATS_KICK		BIT(NOHZ_STATS_KICK_BIT)
2778 /* Update blocked load when entering idle */
2779 #define NOHZ_NEWILB_KICK	BIT(NOHZ_NEWILB_KICK_BIT)
2780 /* Update nohz.next_balance */
2781 #define NOHZ_NEXT_KICK		BIT(NOHZ_NEXT_KICK_BIT)
2782 
2783 #define NOHZ_KICK_MASK	(NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK)
2784 
2785 #define nohz_flags(cpu)	(&cpu_rq(cpu)->nohz_flags)
2786 
2787 extern void nohz_balance_exit_idle(struct rq *rq);
2788 #else
2789 static inline void nohz_balance_exit_idle(struct rq *rq) { }
2790 #endif
2791 
2792 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
2793 extern void nohz_run_idle_balance(int cpu);
2794 #else
2795 static inline void nohz_run_idle_balance(int cpu) { }
2796 #endif
2797 
2798 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2799 struct irqtime {
2800 	u64			total;
2801 	u64			tick_delta;
2802 	u64			irq_start_time;
2803 	struct u64_stats_sync	sync;
2804 };
2805 
2806 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
2807 
2808 /*
2809  * Returns the irqtime minus the softirq time computed by ksoftirqd.
2810  * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime
2811  * and never move forward.
2812  */
2813 static inline u64 irq_time_read(int cpu)
2814 {
2815 	struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
2816 	unsigned int seq;
2817 	u64 total;
2818 
2819 	do {
2820 		seq = __u64_stats_fetch_begin(&irqtime->sync);
2821 		total = irqtime->total;
2822 	} while (__u64_stats_fetch_retry(&irqtime->sync, seq));
2823 
2824 	return total;
2825 }
2826 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
2827 
2828 #ifdef CONFIG_CPU_FREQ
2829 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
2830 
2831 /**
2832  * cpufreq_update_util - Take a note about CPU utilization changes.
2833  * @rq: Runqueue to carry out the update for.
2834  * @flags: Update reason flags.
2835  *
2836  * This function is called by the scheduler on the CPU whose utilization is
2837  * being updated.
2838  *
2839  * It can only be called from RCU-sched read-side critical sections.
2840  *
2841  * The way cpufreq is currently arranged requires it to evaluate the CPU
2842  * performance state (frequency/voltage) on a regular basis to prevent it from
2843  * being stuck in a completely inadequate performance level for too long.
2844  * That is not guaranteed to happen if the updates are only triggered from CFS
2845  * and DL, though, because they may not be coming in if only RT tasks are
2846  * active all the time (or there are RT tasks only).
2847  *
2848  * As a workaround for that issue, this function is called periodically by the
2849  * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
2850  * but that really is a band-aid.  Going forward it should be replaced with
2851  * solutions targeted more specifically at RT tasks.
2852  */
2853 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
2854 {
2855 	struct update_util_data *data;
2856 
2857 	data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
2858 						  cpu_of(rq)));
2859 	if (data)
2860 		data->func(data, rq_clock(rq), flags);
2861 }
2862 #else
2863 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
2864 #endif /* CONFIG_CPU_FREQ */
2865 
2866 #ifdef arch_scale_freq_capacity
2867 # ifndef arch_scale_freq_invariant
2868 #  define arch_scale_freq_invariant()	true
2869 # endif
2870 #else
2871 # define arch_scale_freq_invariant()	false
2872 #endif
2873 
2874 #ifdef CONFIG_SMP
2875 static inline unsigned long capacity_orig_of(int cpu)
2876 {
2877 	return cpu_rq(cpu)->cpu_capacity_orig;
2878 }
2879 
2880 /**
2881  * enum cpu_util_type - CPU utilization type
2882  * @FREQUENCY_UTIL:	Utilization used to select frequency
2883  * @ENERGY_UTIL:	Utilization used during energy calculation
2884  *
2885  * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time
2886  * need to be aggregated differently depending on the usage made of them. This
2887  * enum is used within effective_cpu_util() to differentiate the types of
2888  * utilization expected by the callers, and adjust the aggregation accordingly.
2889  */
2890 enum cpu_util_type {
2891 	FREQUENCY_UTIL,
2892 	ENERGY_UTIL,
2893 };
2894 
2895 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
2896 				 enum cpu_util_type type,
2897 				 struct task_struct *p);
2898 
2899 static inline unsigned long cpu_bw_dl(struct rq *rq)
2900 {
2901 	return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
2902 }
2903 
2904 static inline unsigned long cpu_util_dl(struct rq *rq)
2905 {
2906 	return READ_ONCE(rq->avg_dl.util_avg);
2907 }
2908 
2909 /**
2910  * cpu_util_cfs() - Estimates the amount of CPU capacity used by CFS tasks.
2911  * @cpu: the CPU to get the utilization for.
2912  *
2913  * The unit of the return value must be the same as the one of CPU capacity
2914  * so that CPU utilization can be compared with CPU capacity.
2915  *
2916  * CPU utilization is the sum of running time of runnable tasks plus the
2917  * recent utilization of currently non-runnable tasks on that CPU.
2918  * It represents the amount of CPU capacity currently used by CFS tasks in
2919  * the range [0..max CPU capacity] with max CPU capacity being the CPU
2920  * capacity at f_max.
2921  *
2922  * The estimated CPU utilization is defined as the maximum between CPU
2923  * utilization and sum of the estimated utilization of the currently
2924  * runnable tasks on that CPU. It preserves a utilization "snapshot" of
2925  * previously-executed tasks, which helps better deduce how busy a CPU will
2926  * be when a long-sleeping task wakes up. The contribution to CPU utilization
2927  * of such a task would be significantly decayed at this point of time.
2928  *
2929  * CPU utilization can be higher than the current CPU capacity
2930  * (f_curr/f_max * max CPU capacity) or even the max CPU capacity because
2931  * of rounding errors as well as task migrations or wakeups of new tasks.
2932  * CPU utilization has to be capped to fit into the [0..max CPU capacity]
2933  * range. Otherwise a group of CPUs (CPU0 util = 121% + CPU1 util = 80%)
2934  * could be seen as over-utilized even though CPU1 has 20% of spare CPU
2935  * capacity. CPU utilization is allowed to overshoot current CPU capacity
2936  * though since this is useful for predicting the CPU capacity required
2937  * after task migrations (scheduler-driven DVFS).
2938  *
2939  * Return: (Estimated) utilization for the specified CPU.
2940  */
2941 static inline unsigned long cpu_util_cfs(int cpu)
2942 {
2943 	struct cfs_rq *cfs_rq;
2944 	unsigned long util;
2945 
2946 	cfs_rq = &cpu_rq(cpu)->cfs;
2947 	util = READ_ONCE(cfs_rq->avg.util_avg);
2948 
2949 	if (sched_feat(UTIL_EST)) {
2950 		util = max_t(unsigned long, util,
2951 			     READ_ONCE(cfs_rq->avg.util_est.enqueued));
2952 	}
2953 
2954 	return min(util, capacity_orig_of(cpu));
2955 }
2956 
2957 static inline unsigned long cpu_util_rt(struct rq *rq)
2958 {
2959 	return READ_ONCE(rq->avg_rt.util_avg);
2960 }
2961 #endif
2962 
2963 #ifdef CONFIG_UCLAMP_TASK
2964 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
2965 
2966 /**
2967  * uclamp_rq_util_with - clamp @util with @rq and @p effective uclamp values.
2968  * @rq:		The rq to clamp against. Must not be NULL.
2969  * @util:	The util value to clamp.
2970  * @p:		The task to clamp against. Can be NULL if you want to clamp
2971  *		against @rq only.
2972  *
2973  * Clamps the passed @util to the max(@rq, @p) effective uclamp values.
2974  *
2975  * If sched_uclamp_used static key is disabled, then just return the util
2976  * without any clamping since uclamp aggregation at the rq level in the fast
2977  * path is disabled, rendering this operation a NOP.
2978  *
2979  * Use uclamp_eff_value() if you don't care about uclamp values at rq level. It
2980  * will return the correct effective uclamp value of the task even if the
2981  * static key is disabled.
2982  */
2983 static __always_inline
2984 unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
2985 				  struct task_struct *p)
2986 {
2987 	unsigned long min_util = 0;
2988 	unsigned long max_util = 0;
2989 
2990 	if (!static_branch_likely(&sched_uclamp_used))
2991 		return util;
2992 
2993 	if (p) {
2994 		min_util = uclamp_eff_value(p, UCLAMP_MIN);
2995 		max_util = uclamp_eff_value(p, UCLAMP_MAX);
2996 
2997 		/*
2998 		 * Ignore last runnable task's max clamp, as this task will
2999 		 * reset it. Similarly, no need to read the rq's min clamp.
3000 		 */
3001 		if (rq->uclamp_flags & UCLAMP_FLAG_IDLE)
3002 			goto out;
3003 	}
3004 
3005 	min_util = max_t(unsigned long, min_util, READ_ONCE(rq->uclamp[UCLAMP_MIN].value));
3006 	max_util = max_t(unsigned long, max_util, READ_ONCE(rq->uclamp[UCLAMP_MAX].value));
3007 out:
3008 	/*
3009 	 * Since CPU's {min,max}_util clamps are MAX aggregated considering
3010 	 * RUNNABLE tasks with _different_ clamps, we can end up with an
3011 	 * inversion. Fix it now when the clamps are applied.
3012 	 */
3013 	if (unlikely(min_util >= max_util))
3014 		return min_util;
3015 
3016 	return clamp(util, min_util, max_util);
3017 }
3018 
3019 /* Is the rq being capped/throttled by uclamp_max? */
3020 static inline bool uclamp_rq_is_capped(struct rq *rq)
3021 {
3022 	unsigned long rq_util;
3023 	unsigned long max_util;
3024 
3025 	if (!static_branch_likely(&sched_uclamp_used))
3026 		return false;
3027 
3028 	rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq);
3029 	max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
3030 
3031 	return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util;
3032 }
3033 
3034 /*
3035  * When uclamp is compiled in, the aggregation at rq level is 'turned off'
3036  * by default in the fast path and only gets turned on once userspace performs
3037  * an operation that requires it.
3038  *
3039  * Returns true if userspace opted-in to use uclamp and aggregation at rq level
3040  * hence is active.
3041  */
3042 static inline bool uclamp_is_used(void)
3043 {
3044 	return static_branch_likely(&sched_uclamp_used);
3045 }
3046 #else /* CONFIG_UCLAMP_TASK */
3047 static inline
3048 unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
3049 				  struct task_struct *p)
3050 {
3051 	return util;
3052 }
3053 
3054 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; }
3055 
3056 static inline bool uclamp_is_used(void)
3057 {
3058 	return false;
3059 }
3060 #endif /* CONFIG_UCLAMP_TASK */
3061 
3062 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
3063 static inline unsigned long cpu_util_irq(struct rq *rq)
3064 {
3065 	return rq->avg_irq.util_avg;
3066 }
3067 
3068 static inline
3069 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3070 {
3071 	util *= (max - irq);
3072 	util /= max;
3073 
3074 	return util;
3075 
3076 }
3077 #else
3078 static inline unsigned long cpu_util_irq(struct rq *rq)
3079 {
3080 	return 0;
3081 }
3082 
3083 static inline
3084 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3085 {
3086 	return util;
3087 }
3088 #endif
3089 
3090 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
3091 
3092 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
3093 
3094 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
3095 
3096 static inline bool sched_energy_enabled(void)
3097 {
3098 	return static_branch_unlikely(&sched_energy_present);
3099 }
3100 
3101 #else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
3102 
3103 #define perf_domain_span(pd) NULL
3104 static inline bool sched_energy_enabled(void) { return false; }
3105 
3106 #endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
3107 
3108 #ifdef CONFIG_MEMBARRIER
3109 /*
3110  * The scheduler provides memory barriers required by membarrier between:
3111  * - prior user-space memory accesses and store to rq->membarrier_state,
3112  * - store to rq->membarrier_state and following user-space memory accesses.
3113  * In the same way it provides those guarantees around store to rq->curr.
3114  */
3115 static inline void membarrier_switch_mm(struct rq *rq,
3116 					struct mm_struct *prev_mm,
3117 					struct mm_struct *next_mm)
3118 {
3119 	int membarrier_state;
3120 
3121 	if (prev_mm == next_mm)
3122 		return;
3123 
3124 	membarrier_state = atomic_read(&next_mm->membarrier_state);
3125 	if (READ_ONCE(rq->membarrier_state) == membarrier_state)
3126 		return;
3127 
3128 	WRITE_ONCE(rq->membarrier_state, membarrier_state);
3129 }
3130 #else
3131 static inline void membarrier_switch_mm(struct rq *rq,
3132 					struct mm_struct *prev_mm,
3133 					struct mm_struct *next_mm)
3134 {
3135 }
3136 #endif
3137 
3138 #ifdef CONFIG_SMP
3139 static inline bool is_per_cpu_kthread(struct task_struct *p)
3140 {
3141 	if (!(p->flags & PF_KTHREAD))
3142 		return false;
3143 
3144 	if (p->nr_cpus_allowed != 1)
3145 		return false;
3146 
3147 	return true;
3148 }
3149 #endif
3150 
3151 extern void swake_up_all_locked(struct swait_queue_head *q);
3152 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
3153 
3154 #ifdef CONFIG_PREEMPT_DYNAMIC
3155 extern int preempt_dynamic_mode;
3156 extern int sched_dynamic_mode(const char *str);
3157 extern void sched_dynamic_update(int mode);
3158 #endif
3159 
3160 #endif /* _KERNEL_SCHED_SCHED_H */
3161