xref: /linux/kernel/sched/sched.h (revision e6a901a00822659181c93c86d8bbc2a17779fddc)
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_PARAVIRT
78 # include <asm/paravirt.h>
79 # include <asm/paravirt_api_clock.h>
80 #endif
81 
82 #include <asm/barrier.h>
83 
84 #include "cpupri.h"
85 #include "cpudeadline.h"
86 
87 #ifdef CONFIG_SCHED_DEBUG
88 # define SCHED_WARN_ON(x)      WARN_ONCE(x, #x)
89 #else
90 # define SCHED_WARN_ON(x)      ({ (void)(x), 0; })
91 #endif
92 
93 struct rq;
94 struct cpuidle_state;
95 
96 /* task_struct::on_rq states: */
97 #define TASK_ON_RQ_QUEUED	1
98 #define TASK_ON_RQ_MIGRATING	2
99 
100 extern __read_mostly int scheduler_running;
101 
102 extern unsigned long calc_load_update;
103 extern atomic_long_t calc_load_tasks;
104 
105 extern void calc_global_load_tick(struct rq *this_rq);
106 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
107 
108 extern void call_trace_sched_update_nr_running(struct rq *rq, int count);
109 
110 extern int sysctl_sched_rt_period;
111 extern int sysctl_sched_rt_runtime;
112 extern int sched_rr_timeslice;
113 
114 /*
115  * Helpers for converting nanosecond timing to jiffy resolution
116  */
117 #define NS_TO_JIFFIES(TIME)	((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
118 
119 /*
120  * Increase resolution of nice-level calculations for 64-bit architectures.
121  * The extra resolution improves shares distribution and load balancing of
122  * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
123  * hierarchies, especially on larger systems. This is not a user-visible change
124  * and does not change the user-interface for setting shares/weights.
125  *
126  * We increase resolution only if we have enough bits to allow this increased
127  * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
128  * are pretty high and the returns do not justify the increased costs.
129  *
130  * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
131  * increase coverage and consistency always enable it on 64-bit platforms.
132  */
133 #ifdef CONFIG_64BIT
134 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
135 # define scale_load(w)		((w) << SCHED_FIXEDPOINT_SHIFT)
136 # define scale_load_down(w) \
137 ({ \
138 	unsigned long __w = (w); \
139 	if (__w) \
140 		__w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \
141 	__w; \
142 })
143 #else
144 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT)
145 # define scale_load(w)		(w)
146 # define scale_load_down(w)	(w)
147 #endif
148 
149 /*
150  * Task weight (visible to users) and its load (invisible to users) have
151  * independent resolution, but they should be well calibrated. We use
152  * scale_load() and scale_load_down(w) to convert between them. The
153  * following must be true:
154  *
155  *  scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD
156  *
157  */
158 #define NICE_0_LOAD		(1L << NICE_0_LOAD_SHIFT)
159 
160 /*
161  * Single value that decides SCHED_DEADLINE internal math precision.
162  * 10 -> just above 1us
163  * 9  -> just above 0.5us
164  */
165 #define DL_SCALE		10
166 
167 /*
168  * Single value that denotes runtime == period, ie unlimited time.
169  */
170 #define RUNTIME_INF		((u64)~0ULL)
171 
172 static inline int idle_policy(int policy)
173 {
174 	return policy == SCHED_IDLE;
175 }
176 static inline int fair_policy(int policy)
177 {
178 	return policy == SCHED_NORMAL || policy == SCHED_BATCH;
179 }
180 
181 static inline int rt_policy(int policy)
182 {
183 	return policy == SCHED_FIFO || policy == SCHED_RR;
184 }
185 
186 static inline int dl_policy(int policy)
187 {
188 	return policy == SCHED_DEADLINE;
189 }
190 static inline bool valid_policy(int policy)
191 {
192 	return idle_policy(policy) || fair_policy(policy) ||
193 		rt_policy(policy) || dl_policy(policy);
194 }
195 
196 static inline int task_has_idle_policy(struct task_struct *p)
197 {
198 	return idle_policy(p->policy);
199 }
200 
201 static inline int task_has_rt_policy(struct task_struct *p)
202 {
203 	return rt_policy(p->policy);
204 }
205 
206 static inline int task_has_dl_policy(struct task_struct *p)
207 {
208 	return dl_policy(p->policy);
209 }
210 
211 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
212 
213 static inline void update_avg(u64 *avg, u64 sample)
214 {
215 	s64 diff = sample - *avg;
216 	*avg += diff / 8;
217 }
218 
219 /*
220  * Shifting a value by an exponent greater *or equal* to the size of said value
221  * is UB; cap at size-1.
222  */
223 #define shr_bound(val, shift)							\
224 	(val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1))
225 
226 /*
227  * !! For sched_setattr_nocheck() (kernel) only !!
228  *
229  * This is actually gross. :(
230  *
231  * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
232  * tasks, but still be able to sleep. We need this on platforms that cannot
233  * atomically change clock frequency. Remove once fast switching will be
234  * available on such platforms.
235  *
236  * SUGOV stands for SchedUtil GOVernor.
237  */
238 #define SCHED_FLAG_SUGOV	0x10000000
239 
240 #define SCHED_DL_FLAGS (SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV)
241 
242 static inline bool dl_entity_is_special(const struct sched_dl_entity *dl_se)
243 {
244 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
245 	return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
246 #else
247 	return false;
248 #endif
249 }
250 
251 /*
252  * Tells if entity @a should preempt entity @b.
253  */
254 static inline bool dl_entity_preempt(const struct sched_dl_entity *a,
255 				     const struct sched_dl_entity *b)
256 {
257 	return dl_entity_is_special(a) ||
258 	       dl_time_before(a->deadline, b->deadline);
259 }
260 
261 /*
262  * This is the priority-queue data structure of the RT scheduling class:
263  */
264 struct rt_prio_array {
265 	DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
266 	struct list_head queue[MAX_RT_PRIO];
267 };
268 
269 struct rt_bandwidth {
270 	/* nests inside the rq lock: */
271 	raw_spinlock_t		rt_runtime_lock;
272 	ktime_t			rt_period;
273 	u64			rt_runtime;
274 	struct hrtimer		rt_period_timer;
275 	unsigned int		rt_period_active;
276 };
277 
278 static inline int dl_bandwidth_enabled(void)
279 {
280 	return sysctl_sched_rt_runtime >= 0;
281 }
282 
283 /*
284  * To keep the bandwidth of -deadline tasks under control
285  * we need some place where:
286  *  - store the maximum -deadline bandwidth of each cpu;
287  *  - cache the fraction of bandwidth that is currently allocated in
288  *    each root domain;
289  *
290  * This is all done in the data structure below. It is similar to the
291  * one used for RT-throttling (rt_bandwidth), with the main difference
292  * that, since here we are only interested in admission control, we
293  * do not decrease any runtime while the group "executes", neither we
294  * need a timer to replenish it.
295  *
296  * With respect to SMP, bandwidth is given on a per root domain basis,
297  * meaning that:
298  *  - bw (< 100%) is the deadline bandwidth of each CPU;
299  *  - total_bw is the currently allocated bandwidth in each root domain;
300  */
301 struct dl_bw {
302 	raw_spinlock_t		lock;
303 	u64			bw;
304 	u64			total_bw;
305 };
306 
307 extern void init_dl_bw(struct dl_bw *dl_b);
308 extern int  sched_dl_global_validate(void);
309 extern void sched_dl_do_global(void);
310 extern int  sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
311 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
312 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
313 extern bool __checkparam_dl(const struct sched_attr *attr);
314 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
315 extern int  dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
316 extern int  dl_bw_check_overflow(int cpu);
317 
318 /*
319  * SCHED_DEADLINE supports servers (nested scheduling) with the following
320  * interface:
321  *
322  *   dl_se::rq -- runqueue we belong to.
323  *
324  *   dl_se::server_has_tasks() -- used on bandwidth enforcement; we 'stop' the
325  *                                server when it runs out of tasks to run.
326  *
327  *   dl_se::server_pick() -- nested pick_next_task(); we yield the period if this
328  *                           returns NULL.
329  *
330  *   dl_server_update() -- called from update_curr_common(), propagates runtime
331  *                         to the server.
332  *
333  *   dl_server_start()
334  *   dl_server_stop()  -- start/stop the server when it has (no) tasks.
335  *
336  *   dl_server_init() -- initializes the server.
337  */
338 extern void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec);
339 extern void dl_server_start(struct sched_dl_entity *dl_se);
340 extern void dl_server_stop(struct sched_dl_entity *dl_se);
341 extern void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq,
342 		    dl_server_has_tasks_f has_tasks,
343 		    dl_server_pick_f pick);
344 
345 #ifdef CONFIG_CGROUP_SCHED
346 
347 struct cfs_rq;
348 struct rt_rq;
349 
350 extern struct list_head task_groups;
351 
352 struct cfs_bandwidth {
353 #ifdef CONFIG_CFS_BANDWIDTH
354 	raw_spinlock_t		lock;
355 	ktime_t			period;
356 	u64			quota;
357 	u64			runtime;
358 	u64			burst;
359 	u64			runtime_snap;
360 	s64			hierarchical_quota;
361 
362 	u8			idle;
363 	u8			period_active;
364 	u8			slack_started;
365 	struct hrtimer		period_timer;
366 	struct hrtimer		slack_timer;
367 	struct list_head	throttled_cfs_rq;
368 
369 	/* Statistics: */
370 	int			nr_periods;
371 	int			nr_throttled;
372 	int			nr_burst;
373 	u64			throttled_time;
374 	u64			burst_time;
375 #endif
376 };
377 
378 /* Task group related information */
379 struct task_group {
380 	struct cgroup_subsys_state css;
381 
382 #ifdef CONFIG_FAIR_GROUP_SCHED
383 	/* schedulable entities of this group on each CPU */
384 	struct sched_entity	**se;
385 	/* runqueue "owned" by this group on each CPU */
386 	struct cfs_rq		**cfs_rq;
387 	unsigned long		shares;
388 
389 	/* A positive value indicates that this is a SCHED_IDLE group. */
390 	int			idle;
391 
392 #ifdef	CONFIG_SMP
393 	/*
394 	 * load_avg can be heavily contended at clock tick time, so put
395 	 * it in its own cacheline separated from the fields above which
396 	 * will also be accessed at each tick.
397 	 */
398 	atomic_long_t		load_avg ____cacheline_aligned;
399 #endif
400 #endif
401 
402 #ifdef CONFIG_RT_GROUP_SCHED
403 	struct sched_rt_entity	**rt_se;
404 	struct rt_rq		**rt_rq;
405 
406 	struct rt_bandwidth	rt_bandwidth;
407 #endif
408 
409 	struct rcu_head		rcu;
410 	struct list_head	list;
411 
412 	struct task_group	*parent;
413 	struct list_head	siblings;
414 	struct list_head	children;
415 
416 #ifdef CONFIG_SCHED_AUTOGROUP
417 	struct autogroup	*autogroup;
418 #endif
419 
420 	struct cfs_bandwidth	cfs_bandwidth;
421 
422 #ifdef CONFIG_UCLAMP_TASK_GROUP
423 	/* The two decimal precision [%] value requested from user-space */
424 	unsigned int		uclamp_pct[UCLAMP_CNT];
425 	/* Clamp values requested for a task group */
426 	struct uclamp_se	uclamp_req[UCLAMP_CNT];
427 	/* Effective clamp values used for a task group */
428 	struct uclamp_se	uclamp[UCLAMP_CNT];
429 #endif
430 
431 };
432 
433 #ifdef CONFIG_FAIR_GROUP_SCHED
434 #define ROOT_TASK_GROUP_LOAD	NICE_0_LOAD
435 
436 /*
437  * A weight of 0 or 1 can cause arithmetics problems.
438  * A weight of a cfs_rq is the sum of weights of which entities
439  * are queued on this cfs_rq, so a weight of a entity should not be
440  * too large, so as the shares value of a task group.
441  * (The default weight is 1024 - so there's no practical
442  *  limitation from this.)
443  */
444 #define MIN_SHARES		(1UL <<  1)
445 #define MAX_SHARES		(1UL << 18)
446 #endif
447 
448 typedef int (*tg_visitor)(struct task_group *, void *);
449 
450 extern int walk_tg_tree_from(struct task_group *from,
451 			     tg_visitor down, tg_visitor up, void *data);
452 
453 /*
454  * Iterate the full tree, calling @down when first entering a node and @up when
455  * leaving it for the final time.
456  *
457  * Caller must hold rcu_lock or sufficient equivalent.
458  */
459 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
460 {
461 	return walk_tg_tree_from(&root_task_group, down, up, data);
462 }
463 
464 extern int tg_nop(struct task_group *tg, void *data);
465 
466 #ifdef CONFIG_FAIR_GROUP_SCHED
467 extern void free_fair_sched_group(struct task_group *tg);
468 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
469 extern void online_fair_sched_group(struct task_group *tg);
470 extern void unregister_fair_sched_group(struct task_group *tg);
471 #else
472 static inline void free_fair_sched_group(struct task_group *tg) { }
473 static inline int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
474 {
475        return 1;
476 }
477 static inline void online_fair_sched_group(struct task_group *tg) { }
478 static inline void unregister_fair_sched_group(struct task_group *tg) { }
479 #endif
480 
481 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
482 			struct sched_entity *se, int cpu,
483 			struct sched_entity *parent);
484 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b, struct cfs_bandwidth *parent);
485 
486 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
487 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
488 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
489 extern bool cfs_task_bw_constrained(struct task_struct *p);
490 
491 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
492 		struct sched_rt_entity *rt_se, int cpu,
493 		struct sched_rt_entity *parent);
494 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
495 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
496 extern long sched_group_rt_runtime(struct task_group *tg);
497 extern long sched_group_rt_period(struct task_group *tg);
498 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
499 
500 extern struct task_group *sched_create_group(struct task_group *parent);
501 extern void sched_online_group(struct task_group *tg,
502 			       struct task_group *parent);
503 extern void sched_destroy_group(struct task_group *tg);
504 extern void sched_release_group(struct task_group *tg);
505 
506 extern void sched_move_task(struct task_struct *tsk);
507 
508 #ifdef CONFIG_FAIR_GROUP_SCHED
509 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
510 
511 extern int sched_group_set_idle(struct task_group *tg, long idle);
512 
513 #ifdef CONFIG_SMP
514 extern void set_task_rq_fair(struct sched_entity *se,
515 			     struct cfs_rq *prev, struct cfs_rq *next);
516 #else /* !CONFIG_SMP */
517 static inline void set_task_rq_fair(struct sched_entity *se,
518 			     struct cfs_rq *prev, struct cfs_rq *next) { }
519 #endif /* CONFIG_SMP */
520 #endif /* CONFIG_FAIR_GROUP_SCHED */
521 
522 #else /* CONFIG_CGROUP_SCHED */
523 
524 struct cfs_bandwidth { };
525 static inline bool cfs_task_bw_constrained(struct task_struct *p) { return false; }
526 
527 #endif	/* CONFIG_CGROUP_SCHED */
528 
529 extern void unregister_rt_sched_group(struct task_group *tg);
530 extern void free_rt_sched_group(struct task_group *tg);
531 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
532 
533 /*
534  * u64_u32_load/u64_u32_store
535  *
536  * Use a copy of a u64 value to protect against data race. This is only
537  * applicable for 32-bits architectures.
538  */
539 #ifdef CONFIG_64BIT
540 # define u64_u32_load_copy(var, copy)       var
541 # define u64_u32_store_copy(var, copy, val) (var = val)
542 #else
543 # define u64_u32_load_copy(var, copy)					\
544 ({									\
545 	u64 __val, __val_copy;						\
546 	do {								\
547 		__val_copy = copy;					\
548 		/*							\
549 		 * paired with u64_u32_store_copy(), ordering access	\
550 		 * to var and copy.					\
551 		 */							\
552 		smp_rmb();						\
553 		__val = var;						\
554 	} while (__val != __val_copy);					\
555 	__val;								\
556 })
557 # define u64_u32_store_copy(var, copy, val)				\
558 do {									\
559 	typeof(val) __val = (val);					\
560 	var = __val;							\
561 	/*								\
562 	 * paired with u64_u32_load_copy(), ordering access to var and	\
563 	 * copy.							\
564 	 */								\
565 	smp_wmb();							\
566 	copy = __val;							\
567 } while (0)
568 #endif
569 # define u64_u32_load(var)      u64_u32_load_copy(var, var##_copy)
570 # define u64_u32_store(var, val) u64_u32_store_copy(var, var##_copy, val)
571 
572 /* CFS-related fields in a runqueue */
573 struct cfs_rq {
574 	struct load_weight	load;
575 	unsigned int		nr_running;
576 	unsigned int		h_nr_running;      /* SCHED_{NORMAL,BATCH,IDLE} */
577 	unsigned int		idle_nr_running;   /* SCHED_IDLE */
578 	unsigned int		idle_h_nr_running; /* SCHED_IDLE */
579 
580 	s64			avg_vruntime;
581 	u64			avg_load;
582 
583 	u64			exec_clock;
584 	u64			min_vruntime;
585 #ifdef CONFIG_SCHED_CORE
586 	unsigned int		forceidle_seq;
587 	u64			min_vruntime_fi;
588 #endif
589 
590 #ifndef CONFIG_64BIT
591 	u64			min_vruntime_copy;
592 #endif
593 
594 	struct rb_root_cached	tasks_timeline;
595 
596 	/*
597 	 * 'curr' points to currently running entity on this cfs_rq.
598 	 * It is set to NULL otherwise (i.e when none are currently running).
599 	 */
600 	struct sched_entity	*curr;
601 	struct sched_entity	*next;
602 
603 #ifdef	CONFIG_SCHED_DEBUG
604 	unsigned int		nr_spread_over;
605 #endif
606 
607 #ifdef CONFIG_SMP
608 	/*
609 	 * CFS load tracking
610 	 */
611 	struct sched_avg	avg;
612 #ifndef CONFIG_64BIT
613 	u64			last_update_time_copy;
614 #endif
615 	struct {
616 		raw_spinlock_t	lock ____cacheline_aligned;
617 		int		nr;
618 		unsigned long	load_avg;
619 		unsigned long	util_avg;
620 		unsigned long	runnable_avg;
621 	} removed;
622 
623 #ifdef CONFIG_FAIR_GROUP_SCHED
624 	u64			last_update_tg_load_avg;
625 	unsigned long		tg_load_avg_contrib;
626 	long			propagate;
627 	long			prop_runnable_sum;
628 
629 	/*
630 	 *   h_load = weight * f(tg)
631 	 *
632 	 * Where f(tg) is the recursive weight fraction assigned to
633 	 * this group.
634 	 */
635 	unsigned long		h_load;
636 	u64			last_h_load_update;
637 	struct sched_entity	*h_load_next;
638 #endif /* CONFIG_FAIR_GROUP_SCHED */
639 #endif /* CONFIG_SMP */
640 
641 #ifdef CONFIG_FAIR_GROUP_SCHED
642 	struct rq		*rq;	/* CPU runqueue to which this cfs_rq is attached */
643 
644 	/*
645 	 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
646 	 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
647 	 * (like users, containers etc.)
648 	 *
649 	 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
650 	 * This list is used during load balance.
651 	 */
652 	int			on_list;
653 	struct list_head	leaf_cfs_rq_list;
654 	struct task_group	*tg;	/* group that "owns" this runqueue */
655 
656 	/* Locally cached copy of our task_group's idle value */
657 	int			idle;
658 
659 #ifdef CONFIG_CFS_BANDWIDTH
660 	int			runtime_enabled;
661 	s64			runtime_remaining;
662 
663 	u64			throttled_pelt_idle;
664 #ifndef CONFIG_64BIT
665 	u64                     throttled_pelt_idle_copy;
666 #endif
667 	u64			throttled_clock;
668 	u64			throttled_clock_pelt;
669 	u64			throttled_clock_pelt_time;
670 	u64			throttled_clock_self;
671 	u64			throttled_clock_self_time;
672 	int			throttled;
673 	int			throttle_count;
674 	struct list_head	throttled_list;
675 	struct list_head	throttled_csd_list;
676 #endif /* CONFIG_CFS_BANDWIDTH */
677 #endif /* CONFIG_FAIR_GROUP_SCHED */
678 };
679 
680 static inline int rt_bandwidth_enabled(void)
681 {
682 	return sysctl_sched_rt_runtime >= 0;
683 }
684 
685 /* RT IPI pull logic requires IRQ_WORK */
686 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
687 # define HAVE_RT_PUSH_IPI
688 #endif
689 
690 /* Real-Time classes' related field in a runqueue: */
691 struct rt_rq {
692 	struct rt_prio_array	active;
693 	unsigned int		rt_nr_running;
694 	unsigned int		rr_nr_running;
695 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
696 	struct {
697 		int		curr; /* highest queued rt task prio */
698 #ifdef CONFIG_SMP
699 		int		next; /* next highest */
700 #endif
701 	} highest_prio;
702 #endif
703 #ifdef CONFIG_SMP
704 	int			overloaded;
705 	struct plist_head	pushable_tasks;
706 
707 #endif /* CONFIG_SMP */
708 	int			rt_queued;
709 
710 	int			rt_throttled;
711 	u64			rt_time;
712 	u64			rt_runtime;
713 	/* Nests inside the rq lock: */
714 	raw_spinlock_t		rt_runtime_lock;
715 
716 #ifdef CONFIG_RT_GROUP_SCHED
717 	unsigned int		rt_nr_boosted;
718 
719 	struct rq		*rq;
720 	struct task_group	*tg;
721 #endif
722 };
723 
724 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
725 {
726 	return rt_rq->rt_queued && rt_rq->rt_nr_running;
727 }
728 
729 /* Deadline class' related fields in a runqueue */
730 struct dl_rq {
731 	/* runqueue is an rbtree, ordered by deadline */
732 	struct rb_root_cached	root;
733 
734 	unsigned int		dl_nr_running;
735 
736 #ifdef CONFIG_SMP
737 	/*
738 	 * Deadline values of the currently executing and the
739 	 * earliest ready task on this rq. Caching these facilitates
740 	 * the decision whether or not a ready but not running task
741 	 * should migrate somewhere else.
742 	 */
743 	struct {
744 		u64		curr;
745 		u64		next;
746 	} earliest_dl;
747 
748 	int			overloaded;
749 
750 	/*
751 	 * Tasks on this rq that can be pushed away. They are kept in
752 	 * an rb-tree, ordered by tasks' deadlines, with caching
753 	 * of the leftmost (earliest deadline) element.
754 	 */
755 	struct rb_root_cached	pushable_dl_tasks_root;
756 #else
757 	struct dl_bw		dl_bw;
758 #endif
759 	/*
760 	 * "Active utilization" for this runqueue: increased when a
761 	 * task wakes up (becomes TASK_RUNNING) and decreased when a
762 	 * task blocks
763 	 */
764 	u64			running_bw;
765 
766 	/*
767 	 * Utilization of the tasks "assigned" to this runqueue (including
768 	 * the tasks that are in runqueue and the tasks that executed on this
769 	 * CPU and blocked). Increased when a task moves to this runqueue, and
770 	 * decreased when the task moves away (migrates, changes scheduling
771 	 * policy, or terminates).
772 	 * This is needed to compute the "inactive utilization" for the
773 	 * runqueue (inactive utilization = this_bw - running_bw).
774 	 */
775 	u64			this_bw;
776 	u64			extra_bw;
777 
778 	/*
779 	 * Maximum available bandwidth for reclaiming by SCHED_FLAG_RECLAIM
780 	 * tasks of this rq. Used in calculation of reclaimable bandwidth(GRUB).
781 	 */
782 	u64			max_bw;
783 
784 	/*
785 	 * Inverse of the fraction of CPU utilization that can be reclaimed
786 	 * by the GRUB algorithm.
787 	 */
788 	u64			bw_ratio;
789 };
790 
791 #ifdef CONFIG_FAIR_GROUP_SCHED
792 /* An entity is a task if it doesn't "own" a runqueue */
793 #define entity_is_task(se)	(!se->my_q)
794 
795 static inline void se_update_runnable(struct sched_entity *se)
796 {
797 	if (!entity_is_task(se))
798 		se->runnable_weight = se->my_q->h_nr_running;
799 }
800 
801 static inline long se_runnable(struct sched_entity *se)
802 {
803 	if (entity_is_task(se))
804 		return !!se->on_rq;
805 	else
806 		return se->runnable_weight;
807 }
808 
809 #else
810 #define entity_is_task(se)	1
811 
812 static inline void se_update_runnable(struct sched_entity *se) {}
813 
814 static inline long se_runnable(struct sched_entity *se)
815 {
816 	return !!se->on_rq;
817 }
818 #endif
819 
820 #ifdef CONFIG_SMP
821 /*
822  * XXX we want to get rid of these helpers and use the full load resolution.
823  */
824 static inline long se_weight(struct sched_entity *se)
825 {
826 	return scale_load_down(se->load.weight);
827 }
828 
829 
830 static inline bool sched_asym_prefer(int a, int b)
831 {
832 	return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
833 }
834 
835 struct perf_domain {
836 	struct em_perf_domain *em_pd;
837 	struct perf_domain *next;
838 	struct rcu_head rcu;
839 };
840 
841 /* Scheduling group status flags */
842 #define SG_OVERLOAD		0x1 /* More than one runnable task on a CPU. */
843 #define SG_OVERUTILIZED		0x2 /* One or more CPUs are over-utilized. */
844 
845 /*
846  * We add the notion of a root-domain which will be used to define per-domain
847  * variables. Each exclusive cpuset essentially defines an island domain by
848  * fully partitioning the member CPUs from any other cpuset. Whenever a new
849  * exclusive cpuset is created, we also create and attach a new root-domain
850  * object.
851  *
852  */
853 struct root_domain {
854 	atomic_t		refcount;
855 	atomic_t		rto_count;
856 	struct rcu_head		rcu;
857 	cpumask_var_t		span;
858 	cpumask_var_t		online;
859 
860 	/*
861 	 * Indicate pullable load on at least one CPU, e.g:
862 	 * - More than one runnable task
863 	 * - Running task is misfit
864 	 */
865 	int			overload;
866 
867 	/* Indicate one or more cpus over-utilized (tipping point) */
868 	int			overutilized;
869 
870 	/*
871 	 * The bit corresponding to a CPU gets set here if such CPU has more
872 	 * than one runnable -deadline task (as it is below for RT tasks).
873 	 */
874 	cpumask_var_t		dlo_mask;
875 	atomic_t		dlo_count;
876 	struct dl_bw		dl_bw;
877 	struct cpudl		cpudl;
878 
879 	/*
880 	 * Indicate whether a root_domain's dl_bw has been checked or
881 	 * updated. It's monotonously increasing value.
882 	 *
883 	 * Also, some corner cases, like 'wrap around' is dangerous, but given
884 	 * that u64 is 'big enough'. So that shouldn't be a concern.
885 	 */
886 	u64 visit_gen;
887 
888 #ifdef HAVE_RT_PUSH_IPI
889 	/*
890 	 * For IPI pull requests, loop across the rto_mask.
891 	 */
892 	struct irq_work		rto_push_work;
893 	raw_spinlock_t		rto_lock;
894 	/* These are only updated and read within rto_lock */
895 	int			rto_loop;
896 	int			rto_cpu;
897 	/* These atomics are updated outside of a lock */
898 	atomic_t		rto_loop_next;
899 	atomic_t		rto_loop_start;
900 #endif
901 	/*
902 	 * The "RT overload" flag: it gets set if a CPU has more than
903 	 * one runnable RT task.
904 	 */
905 	cpumask_var_t		rto_mask;
906 	struct cpupri		cpupri;
907 
908 	unsigned long		max_cpu_capacity;
909 
910 	/*
911 	 * NULL-terminated list of performance domains intersecting with the
912 	 * CPUs of the rd. Protected by RCU.
913 	 */
914 	struct perf_domain __rcu *pd;
915 };
916 
917 extern void init_defrootdomain(void);
918 extern int sched_init_domains(const struct cpumask *cpu_map);
919 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
920 extern void sched_get_rd(struct root_domain *rd);
921 extern void sched_put_rd(struct root_domain *rd);
922 
923 #ifdef HAVE_RT_PUSH_IPI
924 extern void rto_push_irq_work_func(struct irq_work *work);
925 #endif
926 #endif /* CONFIG_SMP */
927 
928 #ifdef CONFIG_UCLAMP_TASK
929 /*
930  * struct uclamp_bucket - Utilization clamp bucket
931  * @value: utilization clamp value for tasks on this clamp bucket
932  * @tasks: number of RUNNABLE tasks on this clamp bucket
933  *
934  * Keep track of how many tasks are RUNNABLE for a given utilization
935  * clamp value.
936  */
937 struct uclamp_bucket {
938 	unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
939 	unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
940 };
941 
942 /*
943  * struct uclamp_rq - rq's utilization clamp
944  * @value: currently active clamp values for a rq
945  * @bucket: utilization clamp buckets affecting a rq
946  *
947  * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
948  * A clamp value is affecting a rq when there is at least one task RUNNABLE
949  * (or actually running) with that value.
950  *
951  * There are up to UCLAMP_CNT possible different clamp values, currently there
952  * are only two: minimum utilization and maximum utilization.
953  *
954  * All utilization clamping values are MAX aggregated, since:
955  * - for util_min: we want to run the CPU at least at the max of the minimum
956  *   utilization required by its currently RUNNABLE tasks.
957  * - for util_max: we want to allow the CPU to run up to the max of the
958  *   maximum utilization allowed by its currently RUNNABLE tasks.
959  *
960  * Since on each system we expect only a limited number of different
961  * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
962  * the metrics required to compute all the per-rq utilization clamp values.
963  */
964 struct uclamp_rq {
965 	unsigned int value;
966 	struct uclamp_bucket bucket[UCLAMP_BUCKETS];
967 };
968 
969 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
970 #endif /* CONFIG_UCLAMP_TASK */
971 
972 struct rq;
973 struct balance_callback {
974 	struct balance_callback *next;
975 	void (*func)(struct rq *rq);
976 };
977 
978 /*
979  * This is the main, per-CPU runqueue data structure.
980  *
981  * Locking rule: those places that want to lock multiple runqueues
982  * (such as the load balancing or the thread migration code), lock
983  * acquire operations must be ordered by ascending &runqueue.
984  */
985 struct rq {
986 	/* runqueue lock: */
987 	raw_spinlock_t		__lock;
988 
989 	unsigned int		nr_running;
990 #ifdef CONFIG_NUMA_BALANCING
991 	unsigned int		nr_numa_running;
992 	unsigned int		nr_preferred_running;
993 	unsigned int		numa_migrate_on;
994 #endif
995 #ifdef CONFIG_NO_HZ_COMMON
996 #ifdef CONFIG_SMP
997 	unsigned long		last_blocked_load_update_tick;
998 	unsigned int		has_blocked_load;
999 	call_single_data_t	nohz_csd;
1000 #endif /* CONFIG_SMP */
1001 	unsigned int		nohz_tick_stopped;
1002 	atomic_t		nohz_flags;
1003 #endif /* CONFIG_NO_HZ_COMMON */
1004 
1005 #ifdef CONFIG_SMP
1006 	unsigned int		ttwu_pending;
1007 #endif
1008 	u64			nr_switches;
1009 
1010 #ifdef CONFIG_UCLAMP_TASK
1011 	/* Utilization clamp values based on CPU's RUNNABLE tasks */
1012 	struct uclamp_rq	uclamp[UCLAMP_CNT] ____cacheline_aligned;
1013 	unsigned int		uclamp_flags;
1014 #define UCLAMP_FLAG_IDLE 0x01
1015 #endif
1016 
1017 	struct cfs_rq		cfs;
1018 	struct rt_rq		rt;
1019 	struct dl_rq		dl;
1020 
1021 #ifdef CONFIG_FAIR_GROUP_SCHED
1022 	/* list of leaf cfs_rq on this CPU: */
1023 	struct list_head	leaf_cfs_rq_list;
1024 	struct list_head	*tmp_alone_branch;
1025 #endif /* CONFIG_FAIR_GROUP_SCHED */
1026 
1027 	/*
1028 	 * This is part of a global counter where only the total sum
1029 	 * over all CPUs matters. A task can increase this counter on
1030 	 * one CPU and if it got migrated afterwards it may decrease
1031 	 * it on another CPU. Always updated under the runqueue lock:
1032 	 */
1033 	unsigned int		nr_uninterruptible;
1034 
1035 	struct task_struct __rcu	*curr;
1036 	struct task_struct	*idle;
1037 	struct task_struct	*stop;
1038 	unsigned long		next_balance;
1039 	struct mm_struct	*prev_mm;
1040 
1041 	unsigned int		clock_update_flags;
1042 	u64			clock;
1043 	/* Ensure that all clocks are in the same cache line */
1044 	u64			clock_task ____cacheline_aligned;
1045 	u64			clock_pelt;
1046 	unsigned long		lost_idle_time;
1047 	u64			clock_pelt_idle;
1048 	u64			clock_idle;
1049 #ifndef CONFIG_64BIT
1050 	u64			clock_pelt_idle_copy;
1051 	u64			clock_idle_copy;
1052 #endif
1053 
1054 	atomic_t		nr_iowait;
1055 
1056 #ifdef CONFIG_SCHED_DEBUG
1057 	u64 last_seen_need_resched_ns;
1058 	int ticks_without_resched;
1059 #endif
1060 
1061 #ifdef CONFIG_MEMBARRIER
1062 	int membarrier_state;
1063 #endif
1064 
1065 #ifdef CONFIG_SMP
1066 	struct root_domain		*rd;
1067 	struct sched_domain __rcu	*sd;
1068 
1069 	unsigned long		cpu_capacity;
1070 
1071 	struct balance_callback *balance_callback;
1072 
1073 	unsigned char		nohz_idle_balance;
1074 	unsigned char		idle_balance;
1075 
1076 	unsigned long		misfit_task_load;
1077 
1078 	/* For active balancing */
1079 	int			active_balance;
1080 	int			push_cpu;
1081 	struct cpu_stop_work	active_balance_work;
1082 
1083 	/* CPU of this runqueue: */
1084 	int			cpu;
1085 	int			online;
1086 
1087 	struct list_head cfs_tasks;
1088 
1089 	struct sched_avg	avg_rt;
1090 	struct sched_avg	avg_dl;
1091 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1092 	struct sched_avg	avg_irq;
1093 #endif
1094 #ifdef CONFIG_SCHED_THERMAL_PRESSURE
1095 	struct sched_avg	avg_thermal;
1096 #endif
1097 	u64			idle_stamp;
1098 	u64			avg_idle;
1099 
1100 	/* This is used to determine avg_idle's max value */
1101 	u64			max_idle_balance_cost;
1102 
1103 #ifdef CONFIG_HOTPLUG_CPU
1104 	struct rcuwait		hotplug_wait;
1105 #endif
1106 #endif /* CONFIG_SMP */
1107 
1108 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1109 	u64			prev_irq_time;
1110 #endif
1111 #ifdef CONFIG_PARAVIRT
1112 	u64			prev_steal_time;
1113 #endif
1114 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1115 	u64			prev_steal_time_rq;
1116 #endif
1117 
1118 	/* calc_load related fields */
1119 	unsigned long		calc_load_update;
1120 	long			calc_load_active;
1121 
1122 #ifdef CONFIG_SCHED_HRTICK
1123 #ifdef CONFIG_SMP
1124 	call_single_data_t	hrtick_csd;
1125 #endif
1126 	struct hrtimer		hrtick_timer;
1127 	ktime_t 		hrtick_time;
1128 #endif
1129 
1130 #ifdef CONFIG_SCHEDSTATS
1131 	/* latency stats */
1132 	struct sched_info	rq_sched_info;
1133 	unsigned long long	rq_cpu_time;
1134 	/* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
1135 
1136 	/* sys_sched_yield() stats */
1137 	unsigned int		yld_count;
1138 
1139 	/* schedule() stats */
1140 	unsigned int		sched_count;
1141 	unsigned int		sched_goidle;
1142 
1143 	/* try_to_wake_up() stats */
1144 	unsigned int		ttwu_count;
1145 	unsigned int		ttwu_local;
1146 #endif
1147 
1148 #ifdef CONFIG_CPU_IDLE
1149 	/* Must be inspected within a rcu lock section */
1150 	struct cpuidle_state	*idle_state;
1151 #endif
1152 
1153 #ifdef CONFIG_SMP
1154 	unsigned int		nr_pinned;
1155 #endif
1156 	unsigned int		push_busy;
1157 	struct cpu_stop_work	push_work;
1158 
1159 #ifdef CONFIG_SCHED_CORE
1160 	/* per rq */
1161 	struct rq		*core;
1162 	struct task_struct	*core_pick;
1163 	unsigned int		core_enabled;
1164 	unsigned int		core_sched_seq;
1165 	struct rb_root		core_tree;
1166 
1167 	/* shared state -- careful with sched_core_cpu_deactivate() */
1168 	unsigned int		core_task_seq;
1169 	unsigned int		core_pick_seq;
1170 	unsigned long		core_cookie;
1171 	unsigned int		core_forceidle_count;
1172 	unsigned int		core_forceidle_seq;
1173 	unsigned int		core_forceidle_occupation;
1174 	u64			core_forceidle_start;
1175 #endif
1176 
1177 	/* Scratch cpumask to be temporarily used under rq_lock */
1178 	cpumask_var_t		scratch_mask;
1179 
1180 #if defined(CONFIG_CFS_BANDWIDTH) && defined(CONFIG_SMP)
1181 	call_single_data_t	cfsb_csd;
1182 	struct list_head	cfsb_csd_list;
1183 #endif
1184 };
1185 
1186 #ifdef CONFIG_FAIR_GROUP_SCHED
1187 
1188 /* CPU runqueue to which this cfs_rq is attached */
1189 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1190 {
1191 	return cfs_rq->rq;
1192 }
1193 
1194 #else
1195 
1196 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1197 {
1198 	return container_of(cfs_rq, struct rq, cfs);
1199 }
1200 #endif
1201 
1202 static inline int cpu_of(struct rq *rq)
1203 {
1204 #ifdef CONFIG_SMP
1205 	return rq->cpu;
1206 #else
1207 	return 0;
1208 #endif
1209 }
1210 
1211 #define MDF_PUSH	0x01
1212 
1213 static inline bool is_migration_disabled(struct task_struct *p)
1214 {
1215 #ifdef CONFIG_SMP
1216 	return p->migration_disabled;
1217 #else
1218 	return false;
1219 #endif
1220 }
1221 
1222 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1223 
1224 #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
1225 #define this_rq()		this_cpu_ptr(&runqueues)
1226 #define task_rq(p)		cpu_rq(task_cpu(p))
1227 #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
1228 #define raw_rq()		raw_cpu_ptr(&runqueues)
1229 
1230 struct sched_group;
1231 #ifdef CONFIG_SCHED_CORE
1232 static inline struct cpumask *sched_group_span(struct sched_group *sg);
1233 
1234 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled);
1235 
1236 static inline bool sched_core_enabled(struct rq *rq)
1237 {
1238 	return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled;
1239 }
1240 
1241 static inline bool sched_core_disabled(void)
1242 {
1243 	return !static_branch_unlikely(&__sched_core_enabled);
1244 }
1245 
1246 /*
1247  * Be careful with this function; not for general use. The return value isn't
1248  * stable unless you actually hold a relevant rq->__lock.
1249  */
1250 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1251 {
1252 	if (sched_core_enabled(rq))
1253 		return &rq->core->__lock;
1254 
1255 	return &rq->__lock;
1256 }
1257 
1258 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1259 {
1260 	if (rq->core_enabled)
1261 		return &rq->core->__lock;
1262 
1263 	return &rq->__lock;
1264 }
1265 
1266 bool cfs_prio_less(const struct task_struct *a, const struct task_struct *b,
1267 			bool fi);
1268 void task_vruntime_update(struct rq *rq, struct task_struct *p, bool in_fi);
1269 
1270 /*
1271  * Helpers to check if the CPU's core cookie matches with the task's cookie
1272  * when core scheduling is enabled.
1273  * A special case is that the task's cookie always matches with CPU's core
1274  * cookie if the CPU is in an idle core.
1275  */
1276 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1277 {
1278 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1279 	if (!sched_core_enabled(rq))
1280 		return true;
1281 
1282 	return rq->core->core_cookie == p->core_cookie;
1283 }
1284 
1285 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1286 {
1287 	bool idle_core = true;
1288 	int cpu;
1289 
1290 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1291 	if (!sched_core_enabled(rq))
1292 		return true;
1293 
1294 	for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) {
1295 		if (!available_idle_cpu(cpu)) {
1296 			idle_core = false;
1297 			break;
1298 		}
1299 	}
1300 
1301 	/*
1302 	 * A CPU in an idle core is always the best choice for tasks with
1303 	 * cookies.
1304 	 */
1305 	return idle_core || rq->core->core_cookie == p->core_cookie;
1306 }
1307 
1308 static inline bool sched_group_cookie_match(struct rq *rq,
1309 					    struct task_struct *p,
1310 					    struct sched_group *group)
1311 {
1312 	int cpu;
1313 
1314 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1315 	if (!sched_core_enabled(rq))
1316 		return true;
1317 
1318 	for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
1319 		if (sched_core_cookie_match(cpu_rq(cpu), p))
1320 			return true;
1321 	}
1322 	return false;
1323 }
1324 
1325 static inline bool sched_core_enqueued(struct task_struct *p)
1326 {
1327 	return !RB_EMPTY_NODE(&p->core_node);
1328 }
1329 
1330 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p);
1331 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags);
1332 
1333 extern void sched_core_get(void);
1334 extern void sched_core_put(void);
1335 
1336 #else /* !CONFIG_SCHED_CORE */
1337 
1338 static inline bool sched_core_enabled(struct rq *rq)
1339 {
1340 	return false;
1341 }
1342 
1343 static inline bool sched_core_disabled(void)
1344 {
1345 	return true;
1346 }
1347 
1348 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1349 {
1350 	return &rq->__lock;
1351 }
1352 
1353 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1354 {
1355 	return &rq->__lock;
1356 }
1357 
1358 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1359 {
1360 	return true;
1361 }
1362 
1363 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1364 {
1365 	return true;
1366 }
1367 
1368 static inline bool sched_group_cookie_match(struct rq *rq,
1369 					    struct task_struct *p,
1370 					    struct sched_group *group)
1371 {
1372 	return true;
1373 }
1374 #endif /* CONFIG_SCHED_CORE */
1375 
1376 static inline void lockdep_assert_rq_held(struct rq *rq)
1377 {
1378 	lockdep_assert_held(__rq_lockp(rq));
1379 }
1380 
1381 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass);
1382 extern bool raw_spin_rq_trylock(struct rq *rq);
1383 extern void raw_spin_rq_unlock(struct rq *rq);
1384 
1385 static inline void raw_spin_rq_lock(struct rq *rq)
1386 {
1387 	raw_spin_rq_lock_nested(rq, 0);
1388 }
1389 
1390 static inline void raw_spin_rq_lock_irq(struct rq *rq)
1391 {
1392 	local_irq_disable();
1393 	raw_spin_rq_lock(rq);
1394 }
1395 
1396 static inline void raw_spin_rq_unlock_irq(struct rq *rq)
1397 {
1398 	raw_spin_rq_unlock(rq);
1399 	local_irq_enable();
1400 }
1401 
1402 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq)
1403 {
1404 	unsigned long flags;
1405 	local_irq_save(flags);
1406 	raw_spin_rq_lock(rq);
1407 	return flags;
1408 }
1409 
1410 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags)
1411 {
1412 	raw_spin_rq_unlock(rq);
1413 	local_irq_restore(flags);
1414 }
1415 
1416 #define raw_spin_rq_lock_irqsave(rq, flags)	\
1417 do {						\
1418 	flags = _raw_spin_rq_lock_irqsave(rq);	\
1419 } while (0)
1420 
1421 #ifdef CONFIG_SCHED_SMT
1422 extern void __update_idle_core(struct rq *rq);
1423 
1424 static inline void update_idle_core(struct rq *rq)
1425 {
1426 	if (static_branch_unlikely(&sched_smt_present))
1427 		__update_idle_core(rq);
1428 }
1429 
1430 #else
1431 static inline void update_idle_core(struct rq *rq) { }
1432 #endif
1433 
1434 #ifdef CONFIG_FAIR_GROUP_SCHED
1435 static inline struct task_struct *task_of(struct sched_entity *se)
1436 {
1437 	SCHED_WARN_ON(!entity_is_task(se));
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 p->se.cfs_rq;
1444 }
1445 
1446 /* runqueue on which this entity is (to be) queued */
1447 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1448 {
1449 	return se->cfs_rq;
1450 }
1451 
1452 /* runqueue "owned" by this group */
1453 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1454 {
1455 	return grp->my_q;
1456 }
1457 
1458 #else
1459 
1460 #define task_of(_se)	container_of(_se, struct task_struct, se)
1461 
1462 static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p)
1463 {
1464 	return &task_rq(p)->cfs;
1465 }
1466 
1467 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1468 {
1469 	const struct task_struct *p = task_of(se);
1470 	struct rq *rq = task_rq(p);
1471 
1472 	return &rq->cfs;
1473 }
1474 
1475 /* runqueue "owned" by this group */
1476 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1477 {
1478 	return NULL;
1479 }
1480 #endif
1481 
1482 extern void update_rq_clock(struct rq *rq);
1483 
1484 /*
1485  * rq::clock_update_flags bits
1486  *
1487  * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1488  *  call to __schedule(). This is an optimisation to avoid
1489  *  neighbouring rq clock updates.
1490  *
1491  * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1492  *  in effect and calls to update_rq_clock() are being ignored.
1493  *
1494  * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1495  *  made to update_rq_clock() since the last time rq::lock was pinned.
1496  *
1497  * If inside of __schedule(), clock_update_flags will have been
1498  * shifted left (a left shift is a cheap operation for the fast path
1499  * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1500  *
1501  *	if (rq-clock_update_flags >= RQCF_UPDATED)
1502  *
1503  * to check if %RQCF_UPDATED is set. It'll never be shifted more than
1504  * one position though, because the next rq_unpin_lock() will shift it
1505  * back.
1506  */
1507 #define RQCF_REQ_SKIP		0x01
1508 #define RQCF_ACT_SKIP		0x02
1509 #define RQCF_UPDATED		0x04
1510 
1511 static inline void assert_clock_updated(struct rq *rq)
1512 {
1513 	/*
1514 	 * The only reason for not seeing a clock update since the
1515 	 * last rq_pin_lock() is if we're currently skipping updates.
1516 	 */
1517 	SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
1518 }
1519 
1520 static inline u64 rq_clock(struct rq *rq)
1521 {
1522 	lockdep_assert_rq_held(rq);
1523 	assert_clock_updated(rq);
1524 
1525 	return rq->clock;
1526 }
1527 
1528 static inline u64 rq_clock_task(struct rq *rq)
1529 {
1530 	lockdep_assert_rq_held(rq);
1531 	assert_clock_updated(rq);
1532 
1533 	return rq->clock_task;
1534 }
1535 
1536 /**
1537  * By default the decay is the default pelt decay period.
1538  * The decay shift can change the decay period in
1539  * multiples of 32.
1540  *  Decay shift		Decay period(ms)
1541  *	0			32
1542  *	1			64
1543  *	2			128
1544  *	3			256
1545  *	4			512
1546  */
1547 extern int sched_thermal_decay_shift;
1548 
1549 static inline u64 rq_clock_thermal(struct rq *rq)
1550 {
1551 	return rq_clock_task(rq) >> sched_thermal_decay_shift;
1552 }
1553 
1554 static inline void rq_clock_skip_update(struct rq *rq)
1555 {
1556 	lockdep_assert_rq_held(rq);
1557 	rq->clock_update_flags |= RQCF_REQ_SKIP;
1558 }
1559 
1560 /*
1561  * See rt task throttling, which is the only time a skip
1562  * request is canceled.
1563  */
1564 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1565 {
1566 	lockdep_assert_rq_held(rq);
1567 	rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1568 }
1569 
1570 /*
1571  * During cpu offlining and rq wide unthrottling, we can trigger
1572  * an update_rq_clock() for several cfs and rt runqueues (Typically
1573  * when using list_for_each_entry_*)
1574  * rq_clock_start_loop_update() can be called after updating the clock
1575  * once and before iterating over the list to prevent multiple update.
1576  * After the iterative traversal, we need to call rq_clock_stop_loop_update()
1577  * to clear RQCF_ACT_SKIP of rq->clock_update_flags.
1578  */
1579 static inline void rq_clock_start_loop_update(struct rq *rq)
1580 {
1581 	lockdep_assert_rq_held(rq);
1582 	SCHED_WARN_ON(rq->clock_update_flags & RQCF_ACT_SKIP);
1583 	rq->clock_update_flags |= RQCF_ACT_SKIP;
1584 }
1585 
1586 static inline void rq_clock_stop_loop_update(struct rq *rq)
1587 {
1588 	lockdep_assert_rq_held(rq);
1589 	rq->clock_update_flags &= ~RQCF_ACT_SKIP;
1590 }
1591 
1592 struct rq_flags {
1593 	unsigned long flags;
1594 	struct pin_cookie cookie;
1595 #ifdef CONFIG_SCHED_DEBUG
1596 	/*
1597 	 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1598 	 * current pin context is stashed here in case it needs to be
1599 	 * restored in rq_repin_lock().
1600 	 */
1601 	unsigned int clock_update_flags;
1602 #endif
1603 };
1604 
1605 extern struct balance_callback balance_push_callback;
1606 
1607 /*
1608  * Lockdep annotation that avoids accidental unlocks; it's like a
1609  * sticky/continuous lockdep_assert_held().
1610  *
1611  * This avoids code that has access to 'struct rq *rq' (basically everything in
1612  * the scheduler) from accidentally unlocking the rq if they do not also have a
1613  * copy of the (on-stack) 'struct rq_flags rf'.
1614  *
1615  * Also see Documentation/locking/lockdep-design.rst.
1616  */
1617 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1618 {
1619 	rf->cookie = lockdep_pin_lock(__rq_lockp(rq));
1620 
1621 #ifdef CONFIG_SCHED_DEBUG
1622 	rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1623 	rf->clock_update_flags = 0;
1624 #ifdef CONFIG_SMP
1625 	SCHED_WARN_ON(rq->balance_callback && rq->balance_callback != &balance_push_callback);
1626 #endif
1627 #endif
1628 }
1629 
1630 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1631 {
1632 #ifdef CONFIG_SCHED_DEBUG
1633 	if (rq->clock_update_flags > RQCF_ACT_SKIP)
1634 		rf->clock_update_flags = RQCF_UPDATED;
1635 #endif
1636 
1637 	lockdep_unpin_lock(__rq_lockp(rq), rf->cookie);
1638 }
1639 
1640 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1641 {
1642 	lockdep_repin_lock(__rq_lockp(rq), rf->cookie);
1643 
1644 #ifdef CONFIG_SCHED_DEBUG
1645 	/*
1646 	 * Restore the value we stashed in @rf for this pin context.
1647 	 */
1648 	rq->clock_update_flags |= rf->clock_update_flags;
1649 #endif
1650 }
1651 
1652 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1653 	__acquires(rq->lock);
1654 
1655 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1656 	__acquires(p->pi_lock)
1657 	__acquires(rq->lock);
1658 
1659 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1660 	__releases(rq->lock)
1661 {
1662 	rq_unpin_lock(rq, rf);
1663 	raw_spin_rq_unlock(rq);
1664 }
1665 
1666 static inline void
1667 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1668 	__releases(rq->lock)
1669 	__releases(p->pi_lock)
1670 {
1671 	rq_unpin_lock(rq, rf);
1672 	raw_spin_rq_unlock(rq);
1673 	raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1674 }
1675 
1676 DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct,
1677 		    _T->rq = task_rq_lock(_T->lock, &_T->rf),
1678 		    task_rq_unlock(_T->rq, _T->lock, &_T->rf),
1679 		    struct rq *rq; struct rq_flags rf)
1680 
1681 static inline void
1682 rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1683 	__acquires(rq->lock)
1684 {
1685 	raw_spin_rq_lock_irqsave(rq, rf->flags);
1686 	rq_pin_lock(rq, rf);
1687 }
1688 
1689 static inline void
1690 rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1691 	__acquires(rq->lock)
1692 {
1693 	raw_spin_rq_lock_irq(rq);
1694 	rq_pin_lock(rq, rf);
1695 }
1696 
1697 static inline void
1698 rq_lock(struct rq *rq, struct rq_flags *rf)
1699 	__acquires(rq->lock)
1700 {
1701 	raw_spin_rq_lock(rq);
1702 	rq_pin_lock(rq, rf);
1703 }
1704 
1705 static inline void
1706 rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1707 	__releases(rq->lock)
1708 {
1709 	rq_unpin_lock(rq, rf);
1710 	raw_spin_rq_unlock_irqrestore(rq, rf->flags);
1711 }
1712 
1713 static inline void
1714 rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1715 	__releases(rq->lock)
1716 {
1717 	rq_unpin_lock(rq, rf);
1718 	raw_spin_rq_unlock_irq(rq);
1719 }
1720 
1721 static inline void
1722 rq_unlock(struct rq *rq, struct rq_flags *rf)
1723 	__releases(rq->lock)
1724 {
1725 	rq_unpin_lock(rq, rf);
1726 	raw_spin_rq_unlock(rq);
1727 }
1728 
1729 DEFINE_LOCK_GUARD_1(rq_lock, struct rq,
1730 		    rq_lock(_T->lock, &_T->rf),
1731 		    rq_unlock(_T->lock, &_T->rf),
1732 		    struct rq_flags rf)
1733 
1734 DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq,
1735 		    rq_lock_irq(_T->lock, &_T->rf),
1736 		    rq_unlock_irq(_T->lock, &_T->rf),
1737 		    struct rq_flags rf)
1738 
1739 DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq,
1740 		    rq_lock_irqsave(_T->lock, &_T->rf),
1741 		    rq_unlock_irqrestore(_T->lock, &_T->rf),
1742 		    struct rq_flags rf)
1743 
1744 static inline struct rq *
1745 this_rq_lock_irq(struct rq_flags *rf)
1746 	__acquires(rq->lock)
1747 {
1748 	struct rq *rq;
1749 
1750 	local_irq_disable();
1751 	rq = this_rq();
1752 	rq_lock(rq, rf);
1753 	return rq;
1754 }
1755 
1756 #ifdef CONFIG_NUMA
1757 enum numa_topology_type {
1758 	NUMA_DIRECT,
1759 	NUMA_GLUELESS_MESH,
1760 	NUMA_BACKPLANE,
1761 };
1762 extern enum numa_topology_type sched_numa_topology_type;
1763 extern int sched_max_numa_distance;
1764 extern bool find_numa_distance(int distance);
1765 extern void sched_init_numa(int offline_node);
1766 extern void sched_update_numa(int cpu, bool online);
1767 extern void sched_domains_numa_masks_set(unsigned int cpu);
1768 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1769 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1770 #else
1771 static inline void sched_init_numa(int offline_node) { }
1772 static inline void sched_update_numa(int cpu, bool online) { }
1773 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
1774 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1775 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1776 {
1777 	return nr_cpu_ids;
1778 }
1779 #endif
1780 
1781 #ifdef CONFIG_NUMA_BALANCING
1782 /* The regions in numa_faults array from task_struct */
1783 enum numa_faults_stats {
1784 	NUMA_MEM = 0,
1785 	NUMA_CPU,
1786 	NUMA_MEMBUF,
1787 	NUMA_CPUBUF
1788 };
1789 extern void sched_setnuma(struct task_struct *p, int node);
1790 extern int migrate_task_to(struct task_struct *p, int cpu);
1791 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1792 			int cpu, int scpu);
1793 extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1794 #else
1795 static inline void
1796 init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1797 {
1798 }
1799 #endif /* CONFIG_NUMA_BALANCING */
1800 
1801 #ifdef CONFIG_SMP
1802 
1803 static inline void
1804 queue_balance_callback(struct rq *rq,
1805 		       struct balance_callback *head,
1806 		       void (*func)(struct rq *rq))
1807 {
1808 	lockdep_assert_rq_held(rq);
1809 
1810 	/*
1811 	 * Don't (re)queue an already queued item; nor queue anything when
1812 	 * balance_push() is active, see the comment with
1813 	 * balance_push_callback.
1814 	 */
1815 	if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
1816 		return;
1817 
1818 	head->func = func;
1819 	head->next = rq->balance_callback;
1820 	rq->balance_callback = head;
1821 }
1822 
1823 #define rcu_dereference_check_sched_domain(p) \
1824 	rcu_dereference_check((p), \
1825 			      lockdep_is_held(&sched_domains_mutex))
1826 
1827 /*
1828  * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1829  * See destroy_sched_domains: call_rcu for details.
1830  *
1831  * The domain tree of any CPU may only be accessed from within
1832  * preempt-disabled sections.
1833  */
1834 #define for_each_domain(cpu, __sd) \
1835 	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1836 			__sd; __sd = __sd->parent)
1837 
1838 /* A mask of all the SD flags that have the SDF_SHARED_CHILD metaflag */
1839 #define SD_FLAG(name, mflags) (name * !!((mflags) & SDF_SHARED_CHILD)) |
1840 static const unsigned int SD_SHARED_CHILD_MASK =
1841 #include <linux/sched/sd_flags.h>
1842 0;
1843 #undef SD_FLAG
1844 
1845 /**
1846  * highest_flag_domain - Return highest sched_domain containing flag.
1847  * @cpu:	The CPU whose highest level of sched domain is to
1848  *		be returned.
1849  * @flag:	The flag to check for the highest sched_domain
1850  *		for the given CPU.
1851  *
1852  * Returns the highest sched_domain of a CPU which contains @flag. If @flag has
1853  * the SDF_SHARED_CHILD metaflag, all the children domains also have @flag.
1854  */
1855 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1856 {
1857 	struct sched_domain *sd, *hsd = NULL;
1858 
1859 	for_each_domain(cpu, sd) {
1860 		if (sd->flags & flag) {
1861 			hsd = sd;
1862 			continue;
1863 		}
1864 
1865 		/*
1866 		 * Stop the search if @flag is known to be shared at lower
1867 		 * levels. It will not be found further up.
1868 		 */
1869 		if (flag & SD_SHARED_CHILD_MASK)
1870 			break;
1871 	}
1872 
1873 	return hsd;
1874 }
1875 
1876 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1877 {
1878 	struct sched_domain *sd;
1879 
1880 	for_each_domain(cpu, sd) {
1881 		if (sd->flags & flag)
1882 			break;
1883 	}
1884 
1885 	return sd;
1886 }
1887 
1888 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
1889 DECLARE_PER_CPU(int, sd_llc_size);
1890 DECLARE_PER_CPU(int, sd_llc_id);
1891 DECLARE_PER_CPU(int, sd_share_id);
1892 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
1893 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
1894 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
1895 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
1896 extern struct static_key_false sched_asym_cpucapacity;
1897 extern struct static_key_false sched_cluster_active;
1898 
1899 static __always_inline bool sched_asym_cpucap_active(void)
1900 {
1901 	return static_branch_unlikely(&sched_asym_cpucapacity);
1902 }
1903 
1904 struct sched_group_capacity {
1905 	atomic_t		ref;
1906 	/*
1907 	 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
1908 	 * for a single CPU.
1909 	 */
1910 	unsigned long		capacity;
1911 	unsigned long		min_capacity;		/* Min per-CPU capacity in group */
1912 	unsigned long		max_capacity;		/* Max per-CPU capacity in group */
1913 	unsigned long		next_update;
1914 	int			imbalance;		/* XXX unrelated to capacity but shared group state */
1915 
1916 #ifdef CONFIG_SCHED_DEBUG
1917 	int			id;
1918 #endif
1919 
1920 	unsigned long		cpumask[];		/* Balance mask */
1921 };
1922 
1923 struct sched_group {
1924 	struct sched_group	*next;			/* Must be a circular list */
1925 	atomic_t		ref;
1926 
1927 	unsigned int		group_weight;
1928 	unsigned int		cores;
1929 	struct sched_group_capacity *sgc;
1930 	int			asym_prefer_cpu;	/* CPU of highest priority in group */
1931 	int			flags;
1932 
1933 	/*
1934 	 * The CPUs this group covers.
1935 	 *
1936 	 * NOTE: this field is variable length. (Allocated dynamically
1937 	 * by attaching extra space to the end of the structure,
1938 	 * depending on how many CPUs the kernel has booted up with)
1939 	 */
1940 	unsigned long		cpumask[];
1941 };
1942 
1943 static inline struct cpumask *sched_group_span(struct sched_group *sg)
1944 {
1945 	return to_cpumask(sg->cpumask);
1946 }
1947 
1948 /*
1949  * See build_balance_mask().
1950  */
1951 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
1952 {
1953 	return to_cpumask(sg->sgc->cpumask);
1954 }
1955 
1956 extern int group_balance_cpu(struct sched_group *sg);
1957 
1958 #ifdef CONFIG_SCHED_DEBUG
1959 void update_sched_domain_debugfs(void);
1960 void dirty_sched_domain_sysctl(int cpu);
1961 #else
1962 static inline void update_sched_domain_debugfs(void)
1963 {
1964 }
1965 static inline void dirty_sched_domain_sysctl(int cpu)
1966 {
1967 }
1968 #endif
1969 
1970 extern int sched_update_scaling(void);
1971 
1972 static inline const struct cpumask *task_user_cpus(struct task_struct *p)
1973 {
1974 	if (!p->user_cpus_ptr)
1975 		return cpu_possible_mask; /* &init_task.cpus_mask */
1976 	return p->user_cpus_ptr;
1977 }
1978 #endif /* CONFIG_SMP */
1979 
1980 #include "stats.h"
1981 
1982 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS)
1983 
1984 extern void __sched_core_account_forceidle(struct rq *rq);
1985 
1986 static inline void sched_core_account_forceidle(struct rq *rq)
1987 {
1988 	if (schedstat_enabled())
1989 		__sched_core_account_forceidle(rq);
1990 }
1991 
1992 extern void __sched_core_tick(struct rq *rq);
1993 
1994 static inline void sched_core_tick(struct rq *rq)
1995 {
1996 	if (sched_core_enabled(rq) && schedstat_enabled())
1997 		__sched_core_tick(rq);
1998 }
1999 
2000 #else
2001 
2002 static inline void sched_core_account_forceidle(struct rq *rq) {}
2003 
2004 static inline void sched_core_tick(struct rq *rq) {}
2005 
2006 #endif /* CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS */
2007 
2008 #ifdef CONFIG_CGROUP_SCHED
2009 
2010 /*
2011  * Return the group to which this tasks belongs.
2012  *
2013  * We cannot use task_css() and friends because the cgroup subsystem
2014  * changes that value before the cgroup_subsys::attach() method is called,
2015  * therefore we cannot pin it and might observe the wrong value.
2016  *
2017  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
2018  * core changes this before calling sched_move_task().
2019  *
2020  * Instead we use a 'copy' which is updated from sched_move_task() while
2021  * holding both task_struct::pi_lock and rq::lock.
2022  */
2023 static inline struct task_group *task_group(struct task_struct *p)
2024 {
2025 	return p->sched_task_group;
2026 }
2027 
2028 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
2029 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
2030 {
2031 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
2032 	struct task_group *tg = task_group(p);
2033 #endif
2034 
2035 #ifdef CONFIG_FAIR_GROUP_SCHED
2036 	set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
2037 	p->se.cfs_rq = tg->cfs_rq[cpu];
2038 	p->se.parent = tg->se[cpu];
2039 	p->se.depth = tg->se[cpu] ? tg->se[cpu]->depth + 1 : 0;
2040 #endif
2041 
2042 #ifdef CONFIG_RT_GROUP_SCHED
2043 	p->rt.rt_rq  = tg->rt_rq[cpu];
2044 	p->rt.parent = tg->rt_se[cpu];
2045 #endif
2046 }
2047 
2048 #else /* CONFIG_CGROUP_SCHED */
2049 
2050 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
2051 static inline struct task_group *task_group(struct task_struct *p)
2052 {
2053 	return NULL;
2054 }
2055 
2056 #endif /* CONFIG_CGROUP_SCHED */
2057 
2058 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
2059 {
2060 	set_task_rq(p, cpu);
2061 #ifdef CONFIG_SMP
2062 	/*
2063 	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
2064 	 * successfully executed on another CPU. We must ensure that updates of
2065 	 * per-task data have been completed by this moment.
2066 	 */
2067 	smp_wmb();
2068 	WRITE_ONCE(task_thread_info(p)->cpu, cpu);
2069 	p->wake_cpu = cpu;
2070 #endif
2071 }
2072 
2073 /*
2074  * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
2075  */
2076 #ifdef CONFIG_SCHED_DEBUG
2077 # define const_debug __read_mostly
2078 #else
2079 # define const_debug const
2080 #endif
2081 
2082 #define SCHED_FEAT(name, enabled)	\
2083 	__SCHED_FEAT_##name ,
2084 
2085 enum {
2086 #include "features.h"
2087 	__SCHED_FEAT_NR,
2088 };
2089 
2090 #undef SCHED_FEAT
2091 
2092 #ifdef CONFIG_SCHED_DEBUG
2093 
2094 /*
2095  * To support run-time toggling of sched features, all the translation units
2096  * (but core.c) reference the sysctl_sched_features defined in core.c.
2097  */
2098 extern const_debug unsigned int sysctl_sched_features;
2099 
2100 #ifdef CONFIG_JUMP_LABEL
2101 #define SCHED_FEAT(name, enabled)					\
2102 static __always_inline bool static_branch_##name(struct static_key *key) \
2103 {									\
2104 	return static_key_##enabled(key);				\
2105 }
2106 
2107 #include "features.h"
2108 #undef SCHED_FEAT
2109 
2110 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
2111 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
2112 
2113 #else /* !CONFIG_JUMP_LABEL */
2114 
2115 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2116 
2117 #endif /* CONFIG_JUMP_LABEL */
2118 
2119 #else /* !SCHED_DEBUG */
2120 
2121 /*
2122  * Each translation unit has its own copy of sysctl_sched_features to allow
2123  * constants propagation at compile time and compiler optimization based on
2124  * features default.
2125  */
2126 #define SCHED_FEAT(name, enabled)	\
2127 	(1UL << __SCHED_FEAT_##name) * enabled |
2128 static const_debug __maybe_unused unsigned int sysctl_sched_features =
2129 #include "features.h"
2130 	0;
2131 #undef SCHED_FEAT
2132 
2133 #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2134 
2135 #endif /* SCHED_DEBUG */
2136 
2137 extern struct static_key_false sched_numa_balancing;
2138 extern struct static_key_false sched_schedstats;
2139 
2140 static inline u64 global_rt_period(void)
2141 {
2142 	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
2143 }
2144 
2145 static inline u64 global_rt_runtime(void)
2146 {
2147 	if (sysctl_sched_rt_runtime < 0)
2148 		return RUNTIME_INF;
2149 
2150 	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
2151 }
2152 
2153 static inline int task_current(struct rq *rq, struct task_struct *p)
2154 {
2155 	return rq->curr == p;
2156 }
2157 
2158 static inline int task_on_cpu(struct rq *rq, struct task_struct *p)
2159 {
2160 #ifdef CONFIG_SMP
2161 	return p->on_cpu;
2162 #else
2163 	return task_current(rq, p);
2164 #endif
2165 }
2166 
2167 static inline int task_on_rq_queued(struct task_struct *p)
2168 {
2169 	return p->on_rq == TASK_ON_RQ_QUEUED;
2170 }
2171 
2172 static inline int task_on_rq_migrating(struct task_struct *p)
2173 {
2174 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
2175 }
2176 
2177 /* Wake flags. The first three directly map to some SD flag value */
2178 #define WF_EXEC         0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
2179 #define WF_FORK         0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
2180 #define WF_TTWU         0x08 /* Wakeup;            maps to SD_BALANCE_WAKE */
2181 
2182 #define WF_SYNC         0x10 /* Waker goes to sleep after wakeup */
2183 #define WF_MIGRATED     0x20 /* Internal use, task got migrated */
2184 #define WF_CURRENT_CPU  0x40 /* Prefer to move the wakee to the current CPU. */
2185 
2186 #ifdef CONFIG_SMP
2187 static_assert(WF_EXEC == SD_BALANCE_EXEC);
2188 static_assert(WF_FORK == SD_BALANCE_FORK);
2189 static_assert(WF_TTWU == SD_BALANCE_WAKE);
2190 #endif
2191 
2192 /*
2193  * To aid in avoiding the subversion of "niceness" due to uneven distribution
2194  * of tasks with abnormal "nice" values across CPUs the contribution that
2195  * each task makes to its run queue's load is weighted according to its
2196  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
2197  * scaled version of the new time slice allocation that they receive on time
2198  * slice expiry etc.
2199  */
2200 
2201 #define WEIGHT_IDLEPRIO		3
2202 #define WMULT_IDLEPRIO		1431655765
2203 
2204 extern const int		sched_prio_to_weight[40];
2205 extern const u32		sched_prio_to_wmult[40];
2206 
2207 /*
2208  * {de,en}queue flags:
2209  *
2210  * DEQUEUE_SLEEP  - task is no longer runnable
2211  * ENQUEUE_WAKEUP - task just became runnable
2212  *
2213  * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
2214  *                are in a known state which allows modification. Such pairs
2215  *                should preserve as much state as possible.
2216  *
2217  * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
2218  *        in the runqueue.
2219  *
2220  * NOCLOCK - skip the update_rq_clock() (avoids double updates)
2221  *
2222  * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE)
2223  *
2224  * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
2225  * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
2226  * ENQUEUE_MIGRATED  - the task was migrated during wakeup
2227  *
2228  */
2229 
2230 #define DEQUEUE_SLEEP		0x01
2231 #define DEQUEUE_SAVE		0x02 /* Matches ENQUEUE_RESTORE */
2232 #define DEQUEUE_MOVE		0x04 /* Matches ENQUEUE_MOVE */
2233 #define DEQUEUE_NOCLOCK		0x08 /* Matches ENQUEUE_NOCLOCK */
2234 #define DEQUEUE_MIGRATING	0x100 /* Matches ENQUEUE_MIGRATING */
2235 
2236 #define ENQUEUE_WAKEUP		0x01
2237 #define ENQUEUE_RESTORE		0x02
2238 #define ENQUEUE_MOVE		0x04
2239 #define ENQUEUE_NOCLOCK		0x08
2240 
2241 #define ENQUEUE_HEAD		0x10
2242 #define ENQUEUE_REPLENISH	0x20
2243 #ifdef CONFIG_SMP
2244 #define ENQUEUE_MIGRATED	0x40
2245 #else
2246 #define ENQUEUE_MIGRATED	0x00
2247 #endif
2248 #define ENQUEUE_INITIAL		0x80
2249 #define ENQUEUE_MIGRATING	0x100
2250 
2251 #define RETRY_TASK		((void *)-1UL)
2252 
2253 struct affinity_context {
2254 	const struct cpumask *new_mask;
2255 	struct cpumask *user_mask;
2256 	unsigned int flags;
2257 };
2258 
2259 extern s64 update_curr_common(struct rq *rq);
2260 
2261 struct sched_class {
2262 
2263 #ifdef CONFIG_UCLAMP_TASK
2264 	int uclamp_enabled;
2265 #endif
2266 
2267 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
2268 	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
2269 	void (*yield_task)   (struct rq *rq);
2270 	bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
2271 
2272 	void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags);
2273 
2274 	struct task_struct *(*pick_next_task)(struct rq *rq);
2275 
2276 	void (*put_prev_task)(struct rq *rq, struct task_struct *p);
2277 	void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
2278 
2279 #ifdef CONFIG_SMP
2280 	int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2281 	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
2282 
2283 	struct task_struct * (*pick_task)(struct rq *rq);
2284 
2285 	void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
2286 
2287 	void (*task_woken)(struct rq *this_rq, struct task_struct *task);
2288 
2289 	void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx);
2290 
2291 	void (*rq_online)(struct rq *rq);
2292 	void (*rq_offline)(struct rq *rq);
2293 
2294 	struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
2295 #endif
2296 
2297 	void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
2298 	void (*task_fork)(struct task_struct *p);
2299 	void (*task_dead)(struct task_struct *p);
2300 
2301 	/*
2302 	 * The switched_from() call is allowed to drop rq->lock, therefore we
2303 	 * cannot assume the switched_from/switched_to pair is serialized by
2304 	 * rq->lock. They are however serialized by p->pi_lock.
2305 	 */
2306 	void (*switched_from)(struct rq *this_rq, struct task_struct *task);
2307 	void (*switched_to)  (struct rq *this_rq, struct task_struct *task);
2308 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
2309 			      int oldprio);
2310 
2311 	unsigned int (*get_rr_interval)(struct rq *rq,
2312 					struct task_struct *task);
2313 
2314 	void (*update_curr)(struct rq *rq);
2315 
2316 #ifdef CONFIG_FAIR_GROUP_SCHED
2317 	void (*task_change_group)(struct task_struct *p);
2318 #endif
2319 
2320 #ifdef CONFIG_SCHED_CORE
2321 	int (*task_is_throttled)(struct task_struct *p, int cpu);
2322 #endif
2323 };
2324 
2325 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
2326 {
2327 	WARN_ON_ONCE(rq->curr != prev);
2328 	prev->sched_class->put_prev_task(rq, prev);
2329 }
2330 
2331 static inline void set_next_task(struct rq *rq, struct task_struct *next)
2332 {
2333 	next->sched_class->set_next_task(rq, next, false);
2334 }
2335 
2336 
2337 /*
2338  * Helper to define a sched_class instance; each one is placed in a separate
2339  * section which is ordered by the linker script:
2340  *
2341  *   include/asm-generic/vmlinux.lds.h
2342  *
2343  * *CAREFUL* they are laid out in *REVERSE* order!!!
2344  *
2345  * Also enforce alignment on the instance, not the type, to guarantee layout.
2346  */
2347 #define DEFINE_SCHED_CLASS(name) \
2348 const struct sched_class name##_sched_class \
2349 	__aligned(__alignof__(struct sched_class)) \
2350 	__section("__" #name "_sched_class")
2351 
2352 /* Defined in include/asm-generic/vmlinux.lds.h */
2353 extern struct sched_class __sched_class_highest[];
2354 extern struct sched_class __sched_class_lowest[];
2355 
2356 #define for_class_range(class, _from, _to) \
2357 	for (class = (_from); class < (_to); class++)
2358 
2359 #define for_each_class(class) \
2360 	for_class_range(class, __sched_class_highest, __sched_class_lowest)
2361 
2362 #define sched_class_above(_a, _b)	((_a) < (_b))
2363 
2364 extern const struct sched_class stop_sched_class;
2365 extern const struct sched_class dl_sched_class;
2366 extern const struct sched_class rt_sched_class;
2367 extern const struct sched_class fair_sched_class;
2368 extern const struct sched_class idle_sched_class;
2369 
2370 static inline bool sched_stop_runnable(struct rq *rq)
2371 {
2372 	return rq->stop && task_on_rq_queued(rq->stop);
2373 }
2374 
2375 static inline bool sched_dl_runnable(struct rq *rq)
2376 {
2377 	return rq->dl.dl_nr_running > 0;
2378 }
2379 
2380 static inline bool sched_rt_runnable(struct rq *rq)
2381 {
2382 	return rq->rt.rt_queued > 0;
2383 }
2384 
2385 static inline bool sched_fair_runnable(struct rq *rq)
2386 {
2387 	return rq->cfs.nr_running > 0;
2388 }
2389 
2390 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2391 extern struct task_struct *pick_next_task_idle(struct rq *rq);
2392 
2393 #define SCA_CHECK		0x01
2394 #define SCA_MIGRATE_DISABLE	0x02
2395 #define SCA_MIGRATE_ENABLE	0x04
2396 #define SCA_USER		0x08
2397 
2398 #ifdef CONFIG_SMP
2399 
2400 extern void update_group_capacity(struct sched_domain *sd, int cpu);
2401 
2402 extern void trigger_load_balance(struct rq *rq);
2403 
2404 extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx);
2405 
2406 static inline struct task_struct *get_push_task(struct rq *rq)
2407 {
2408 	struct task_struct *p = rq->curr;
2409 
2410 	lockdep_assert_rq_held(rq);
2411 
2412 	if (rq->push_busy)
2413 		return NULL;
2414 
2415 	if (p->nr_cpus_allowed == 1)
2416 		return NULL;
2417 
2418 	if (p->migration_disabled)
2419 		return NULL;
2420 
2421 	rq->push_busy = true;
2422 	return get_task_struct(p);
2423 }
2424 
2425 extern int push_cpu_stop(void *arg);
2426 
2427 #endif
2428 
2429 #ifdef CONFIG_CPU_IDLE
2430 static inline void idle_set_state(struct rq *rq,
2431 				  struct cpuidle_state *idle_state)
2432 {
2433 	rq->idle_state = idle_state;
2434 }
2435 
2436 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2437 {
2438 	SCHED_WARN_ON(!rcu_read_lock_held());
2439 
2440 	return rq->idle_state;
2441 }
2442 #else
2443 static inline void idle_set_state(struct rq *rq,
2444 				  struct cpuidle_state *idle_state)
2445 {
2446 }
2447 
2448 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2449 {
2450 	return NULL;
2451 }
2452 #endif
2453 
2454 extern void schedule_idle(void);
2455 asmlinkage void schedule_user(void);
2456 
2457 extern void sysrq_sched_debug_show(void);
2458 extern void sched_init_granularity(void);
2459 extern void update_max_interval(void);
2460 
2461 extern void init_sched_dl_class(void);
2462 extern void init_sched_rt_class(void);
2463 extern void init_sched_fair_class(void);
2464 
2465 extern void reweight_task(struct task_struct *p, int prio);
2466 
2467 extern void resched_curr(struct rq *rq);
2468 extern void resched_cpu(int cpu);
2469 
2470 extern struct rt_bandwidth def_rt_bandwidth;
2471 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
2472 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq);
2473 
2474 extern void init_dl_entity(struct sched_dl_entity *dl_se);
2475 
2476 #define BW_SHIFT		20
2477 #define BW_UNIT			(1 << BW_SHIFT)
2478 #define RATIO_SHIFT		8
2479 #define MAX_BW_BITS		(64 - BW_SHIFT)
2480 #define MAX_BW			((1ULL << MAX_BW_BITS) - 1)
2481 unsigned long to_ratio(u64 period, u64 runtime);
2482 
2483 extern void init_entity_runnable_average(struct sched_entity *se);
2484 extern void post_init_entity_util_avg(struct task_struct *p);
2485 
2486 #ifdef CONFIG_NO_HZ_FULL
2487 extern bool sched_can_stop_tick(struct rq *rq);
2488 extern int __init sched_tick_offload_init(void);
2489 
2490 /*
2491  * Tick may be needed by tasks in the runqueue depending on their policy and
2492  * requirements. If tick is needed, lets send the target an IPI to kick it out of
2493  * nohz mode if necessary.
2494  */
2495 static inline void sched_update_tick_dependency(struct rq *rq)
2496 {
2497 	int cpu = cpu_of(rq);
2498 
2499 	if (!tick_nohz_full_cpu(cpu))
2500 		return;
2501 
2502 	if (sched_can_stop_tick(rq))
2503 		tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
2504 	else
2505 		tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
2506 }
2507 #else
2508 static inline int sched_tick_offload_init(void) { return 0; }
2509 static inline void sched_update_tick_dependency(struct rq *rq) { }
2510 #endif
2511 
2512 static inline void add_nr_running(struct rq *rq, unsigned count)
2513 {
2514 	unsigned prev_nr = rq->nr_running;
2515 
2516 	rq->nr_running = prev_nr + count;
2517 	if (trace_sched_update_nr_running_tp_enabled()) {
2518 		call_trace_sched_update_nr_running(rq, count);
2519 	}
2520 
2521 #ifdef CONFIG_SMP
2522 	if (prev_nr < 2 && rq->nr_running >= 2) {
2523 		if (!READ_ONCE(rq->rd->overload))
2524 			WRITE_ONCE(rq->rd->overload, 1);
2525 	}
2526 #endif
2527 
2528 	sched_update_tick_dependency(rq);
2529 }
2530 
2531 static inline void sub_nr_running(struct rq *rq, unsigned count)
2532 {
2533 	rq->nr_running -= count;
2534 	if (trace_sched_update_nr_running_tp_enabled()) {
2535 		call_trace_sched_update_nr_running(rq, -count);
2536 	}
2537 
2538 	/* Check if we still need preemption */
2539 	sched_update_tick_dependency(rq);
2540 }
2541 
2542 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
2543 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
2544 
2545 extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags);
2546 
2547 #ifdef CONFIG_PREEMPT_RT
2548 #define SCHED_NR_MIGRATE_BREAK 8
2549 #else
2550 #define SCHED_NR_MIGRATE_BREAK 32
2551 #endif
2552 
2553 extern const_debug unsigned int sysctl_sched_nr_migrate;
2554 extern const_debug unsigned int sysctl_sched_migration_cost;
2555 
2556 extern unsigned int sysctl_sched_base_slice;
2557 
2558 #ifdef CONFIG_SCHED_DEBUG
2559 extern int sysctl_resched_latency_warn_ms;
2560 extern int sysctl_resched_latency_warn_once;
2561 
2562 extern unsigned int sysctl_sched_tunable_scaling;
2563 
2564 extern unsigned int sysctl_numa_balancing_scan_delay;
2565 extern unsigned int sysctl_numa_balancing_scan_period_min;
2566 extern unsigned int sysctl_numa_balancing_scan_period_max;
2567 extern unsigned int sysctl_numa_balancing_scan_size;
2568 extern unsigned int sysctl_numa_balancing_hot_threshold;
2569 #endif
2570 
2571 #ifdef CONFIG_SCHED_HRTICK
2572 
2573 /*
2574  * Use hrtick when:
2575  *  - enabled by features
2576  *  - hrtimer is actually high res
2577  */
2578 static inline int hrtick_enabled(struct rq *rq)
2579 {
2580 	if (!cpu_active(cpu_of(rq)))
2581 		return 0;
2582 	return hrtimer_is_hres_active(&rq->hrtick_timer);
2583 }
2584 
2585 static inline int hrtick_enabled_fair(struct rq *rq)
2586 {
2587 	if (!sched_feat(HRTICK))
2588 		return 0;
2589 	return hrtick_enabled(rq);
2590 }
2591 
2592 static inline int hrtick_enabled_dl(struct rq *rq)
2593 {
2594 	if (!sched_feat(HRTICK_DL))
2595 		return 0;
2596 	return hrtick_enabled(rq);
2597 }
2598 
2599 void hrtick_start(struct rq *rq, u64 delay);
2600 
2601 #else
2602 
2603 static inline int hrtick_enabled_fair(struct rq *rq)
2604 {
2605 	return 0;
2606 }
2607 
2608 static inline int hrtick_enabled_dl(struct rq *rq)
2609 {
2610 	return 0;
2611 }
2612 
2613 static inline int hrtick_enabled(struct rq *rq)
2614 {
2615 	return 0;
2616 }
2617 
2618 #endif /* CONFIG_SCHED_HRTICK */
2619 
2620 #ifndef arch_scale_freq_tick
2621 static __always_inline
2622 void arch_scale_freq_tick(void)
2623 {
2624 }
2625 #endif
2626 
2627 #ifndef arch_scale_freq_capacity
2628 /**
2629  * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
2630  * @cpu: the CPU in question.
2631  *
2632  * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
2633  *
2634  *     f_curr
2635  *     ------ * SCHED_CAPACITY_SCALE
2636  *     f_max
2637  */
2638 static __always_inline
2639 unsigned long arch_scale_freq_capacity(int cpu)
2640 {
2641 	return SCHED_CAPACITY_SCALE;
2642 }
2643 #endif
2644 
2645 #ifdef CONFIG_SCHED_DEBUG
2646 /*
2647  * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to
2648  * acquire rq lock instead of rq_lock(). So at the end of these two functions
2649  * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of
2650  * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning.
2651  */
2652 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2)
2653 {
2654 	rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
2655 	/* rq1 == rq2 for !CONFIG_SMP, so just clear RQCF_UPDATED once. */
2656 #ifdef CONFIG_SMP
2657 	rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
2658 #endif
2659 }
2660 #else
2661 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2) {}
2662 #endif
2663 
2664 #define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...)		\
2665 __DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__) \
2666 static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2) \
2667 { class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t;	\
2668   _lock; return _t; }
2669 
2670 #ifdef CONFIG_SMP
2671 
2672 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2)
2673 {
2674 #ifdef CONFIG_SCHED_CORE
2675 	/*
2676 	 * In order to not have {0,2},{1,3} turn into into an AB-BA,
2677 	 * order by core-id first and cpu-id second.
2678 	 *
2679 	 * Notably:
2680 	 *
2681 	 *	double_rq_lock(0,3); will take core-0, core-1 lock
2682 	 *	double_rq_lock(1,2); will take core-1, core-0 lock
2683 	 *
2684 	 * when only cpu-id is considered.
2685 	 */
2686 	if (rq1->core->cpu < rq2->core->cpu)
2687 		return true;
2688 	if (rq1->core->cpu > rq2->core->cpu)
2689 		return false;
2690 
2691 	/*
2692 	 * __sched_core_flip() relies on SMT having cpu-id lock order.
2693 	 */
2694 #endif
2695 	return rq1->cpu < rq2->cpu;
2696 }
2697 
2698 extern void double_rq_lock(struct rq *rq1, struct rq *rq2);
2699 
2700 #ifdef CONFIG_PREEMPTION
2701 
2702 /*
2703  * fair double_lock_balance: Safely acquires both rq->locks in a fair
2704  * way at the expense of forcing extra atomic operations in all
2705  * invocations.  This assures that the double_lock is acquired using the
2706  * same underlying policy as the spinlock_t on this architecture, which
2707  * reduces latency compared to the unfair variant below.  However, it
2708  * also adds more overhead and therefore may reduce throughput.
2709  */
2710 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2711 	__releases(this_rq->lock)
2712 	__acquires(busiest->lock)
2713 	__acquires(this_rq->lock)
2714 {
2715 	raw_spin_rq_unlock(this_rq);
2716 	double_rq_lock(this_rq, busiest);
2717 
2718 	return 1;
2719 }
2720 
2721 #else
2722 /*
2723  * Unfair double_lock_balance: Optimizes throughput at the expense of
2724  * latency by eliminating extra atomic operations when the locks are
2725  * already in proper order on entry.  This favors lower CPU-ids and will
2726  * grant the double lock to lower CPUs over higher ids under contention,
2727  * regardless of entry order into the function.
2728  */
2729 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2730 	__releases(this_rq->lock)
2731 	__acquires(busiest->lock)
2732 	__acquires(this_rq->lock)
2733 {
2734 	if (__rq_lockp(this_rq) == __rq_lockp(busiest) ||
2735 	    likely(raw_spin_rq_trylock(busiest))) {
2736 		double_rq_clock_clear_update(this_rq, busiest);
2737 		return 0;
2738 	}
2739 
2740 	if (rq_order_less(this_rq, busiest)) {
2741 		raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING);
2742 		double_rq_clock_clear_update(this_rq, busiest);
2743 		return 0;
2744 	}
2745 
2746 	raw_spin_rq_unlock(this_rq);
2747 	double_rq_lock(this_rq, busiest);
2748 
2749 	return 1;
2750 }
2751 
2752 #endif /* CONFIG_PREEMPTION */
2753 
2754 /*
2755  * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
2756  */
2757 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
2758 {
2759 	lockdep_assert_irqs_disabled();
2760 
2761 	return _double_lock_balance(this_rq, busiest);
2762 }
2763 
2764 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
2765 	__releases(busiest->lock)
2766 {
2767 	if (__rq_lockp(this_rq) != __rq_lockp(busiest))
2768 		raw_spin_rq_unlock(busiest);
2769 	lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_);
2770 }
2771 
2772 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
2773 {
2774 	if (l1 > l2)
2775 		swap(l1, l2);
2776 
2777 	spin_lock(l1);
2778 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2779 }
2780 
2781 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
2782 {
2783 	if (l1 > l2)
2784 		swap(l1, l2);
2785 
2786 	spin_lock_irq(l1);
2787 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2788 }
2789 
2790 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
2791 {
2792 	if (l1 > l2)
2793 		swap(l1, l2);
2794 
2795 	raw_spin_lock(l1);
2796 	raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2797 }
2798 
2799 static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2)
2800 {
2801 	raw_spin_unlock(l1);
2802 	raw_spin_unlock(l2);
2803 }
2804 
2805 DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t,
2806 		    double_raw_lock(_T->lock, _T->lock2),
2807 		    double_raw_unlock(_T->lock, _T->lock2))
2808 
2809 /*
2810  * double_rq_unlock - safely unlock two runqueues
2811  *
2812  * Note this does not restore interrupts like task_rq_unlock,
2813  * you need to do so manually after calling.
2814  */
2815 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2816 	__releases(rq1->lock)
2817 	__releases(rq2->lock)
2818 {
2819 	if (__rq_lockp(rq1) != __rq_lockp(rq2))
2820 		raw_spin_rq_unlock(rq2);
2821 	else
2822 		__release(rq2->lock);
2823 	raw_spin_rq_unlock(rq1);
2824 }
2825 
2826 extern void set_rq_online (struct rq *rq);
2827 extern void set_rq_offline(struct rq *rq);
2828 extern bool sched_smp_initialized;
2829 
2830 #else /* CONFIG_SMP */
2831 
2832 /*
2833  * double_rq_lock - safely lock two runqueues
2834  *
2835  * Note this does not disable interrupts like task_rq_lock,
2836  * you need to do so manually before calling.
2837  */
2838 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2839 	__acquires(rq1->lock)
2840 	__acquires(rq2->lock)
2841 {
2842 	WARN_ON_ONCE(!irqs_disabled());
2843 	WARN_ON_ONCE(rq1 != rq2);
2844 	raw_spin_rq_lock(rq1);
2845 	__acquire(rq2->lock);	/* Fake it out ;) */
2846 	double_rq_clock_clear_update(rq1, rq2);
2847 }
2848 
2849 /*
2850  * double_rq_unlock - safely unlock two runqueues
2851  *
2852  * Note this does not restore interrupts like task_rq_unlock,
2853  * you need to do so manually after calling.
2854  */
2855 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2856 	__releases(rq1->lock)
2857 	__releases(rq2->lock)
2858 {
2859 	WARN_ON_ONCE(rq1 != rq2);
2860 	raw_spin_rq_unlock(rq1);
2861 	__release(rq2->lock);
2862 }
2863 
2864 #endif
2865 
2866 DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq,
2867 		    double_rq_lock(_T->lock, _T->lock2),
2868 		    double_rq_unlock(_T->lock, _T->lock2))
2869 
2870 extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq);
2871 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
2872 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
2873 
2874 #ifdef	CONFIG_SCHED_DEBUG
2875 extern bool sched_debug_verbose;
2876 
2877 extern void print_cfs_stats(struct seq_file *m, int cpu);
2878 extern void print_rt_stats(struct seq_file *m, int cpu);
2879 extern void print_dl_stats(struct seq_file *m, int cpu);
2880 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
2881 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
2882 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
2883 
2884 extern void resched_latency_warn(int cpu, u64 latency);
2885 #ifdef CONFIG_NUMA_BALANCING
2886 extern void
2887 show_numa_stats(struct task_struct *p, struct seq_file *m);
2888 extern void
2889 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
2890 	unsigned long tpf, unsigned long gsf, unsigned long gpf);
2891 #endif /* CONFIG_NUMA_BALANCING */
2892 #else
2893 static inline void resched_latency_warn(int cpu, u64 latency) {}
2894 #endif /* CONFIG_SCHED_DEBUG */
2895 
2896 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
2897 extern void init_rt_rq(struct rt_rq *rt_rq);
2898 extern void init_dl_rq(struct dl_rq *dl_rq);
2899 
2900 extern void cfs_bandwidth_usage_inc(void);
2901 extern void cfs_bandwidth_usage_dec(void);
2902 
2903 #ifdef CONFIG_NO_HZ_COMMON
2904 #define NOHZ_BALANCE_KICK_BIT	0
2905 #define NOHZ_STATS_KICK_BIT	1
2906 #define NOHZ_NEWILB_KICK_BIT	2
2907 #define NOHZ_NEXT_KICK_BIT	3
2908 
2909 /* Run rebalance_domains() */
2910 #define NOHZ_BALANCE_KICK	BIT(NOHZ_BALANCE_KICK_BIT)
2911 /* Update blocked load */
2912 #define NOHZ_STATS_KICK		BIT(NOHZ_STATS_KICK_BIT)
2913 /* Update blocked load when entering idle */
2914 #define NOHZ_NEWILB_KICK	BIT(NOHZ_NEWILB_KICK_BIT)
2915 /* Update nohz.next_balance */
2916 #define NOHZ_NEXT_KICK		BIT(NOHZ_NEXT_KICK_BIT)
2917 
2918 #define NOHZ_KICK_MASK	(NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK)
2919 
2920 #define nohz_flags(cpu)	(&cpu_rq(cpu)->nohz_flags)
2921 
2922 extern void nohz_balance_exit_idle(struct rq *rq);
2923 #else
2924 static inline void nohz_balance_exit_idle(struct rq *rq) { }
2925 #endif
2926 
2927 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
2928 extern void nohz_run_idle_balance(int cpu);
2929 #else
2930 static inline void nohz_run_idle_balance(int cpu) { }
2931 #endif
2932 
2933 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2934 struct irqtime {
2935 	u64			total;
2936 	u64			tick_delta;
2937 	u64			irq_start_time;
2938 	struct u64_stats_sync	sync;
2939 };
2940 
2941 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
2942 
2943 /*
2944  * Returns the irqtime minus the softirq time computed by ksoftirqd.
2945  * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime
2946  * and never move forward.
2947  */
2948 static inline u64 irq_time_read(int cpu)
2949 {
2950 	struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
2951 	unsigned int seq;
2952 	u64 total;
2953 
2954 	do {
2955 		seq = __u64_stats_fetch_begin(&irqtime->sync);
2956 		total = irqtime->total;
2957 	} while (__u64_stats_fetch_retry(&irqtime->sync, seq));
2958 
2959 	return total;
2960 }
2961 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
2962 
2963 #ifdef CONFIG_CPU_FREQ
2964 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
2965 
2966 /**
2967  * cpufreq_update_util - Take a note about CPU utilization changes.
2968  * @rq: Runqueue to carry out the update for.
2969  * @flags: Update reason flags.
2970  *
2971  * This function is called by the scheduler on the CPU whose utilization is
2972  * being updated.
2973  *
2974  * It can only be called from RCU-sched read-side critical sections.
2975  *
2976  * The way cpufreq is currently arranged requires it to evaluate the CPU
2977  * performance state (frequency/voltage) on a regular basis to prevent it from
2978  * being stuck in a completely inadequate performance level for too long.
2979  * That is not guaranteed to happen if the updates are only triggered from CFS
2980  * and DL, though, because they may not be coming in if only RT tasks are
2981  * active all the time (or there are RT tasks only).
2982  *
2983  * As a workaround for that issue, this function is called periodically by the
2984  * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
2985  * but that really is a band-aid.  Going forward it should be replaced with
2986  * solutions targeted more specifically at RT tasks.
2987  */
2988 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
2989 {
2990 	struct update_util_data *data;
2991 
2992 	data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
2993 						  cpu_of(rq)));
2994 	if (data)
2995 		data->func(data, rq_clock(rq), flags);
2996 }
2997 #else
2998 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
2999 #endif /* CONFIG_CPU_FREQ */
3000 
3001 #ifdef arch_scale_freq_capacity
3002 # ifndef arch_scale_freq_invariant
3003 #  define arch_scale_freq_invariant()	true
3004 # endif
3005 #else
3006 # define arch_scale_freq_invariant()	false
3007 #endif
3008 
3009 #ifdef CONFIG_SMP
3010 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
3011 				 unsigned long *min,
3012 				 unsigned long *max);
3013 
3014 unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual,
3015 				 unsigned long min,
3016 				 unsigned long max);
3017 
3018 
3019 /*
3020  * Verify the fitness of task @p to run on @cpu taking into account the
3021  * CPU original capacity and the runtime/deadline ratio of the task.
3022  *
3023  * The function will return true if the original capacity of @cpu is
3024  * greater than or equal to task's deadline density right shifted by
3025  * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise.
3026  */
3027 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
3028 {
3029 	unsigned long cap = arch_scale_cpu_capacity(cpu);
3030 
3031 	return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT);
3032 }
3033 
3034 static inline unsigned long cpu_bw_dl(struct rq *rq)
3035 {
3036 	return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
3037 }
3038 
3039 static inline unsigned long cpu_util_dl(struct rq *rq)
3040 {
3041 	return READ_ONCE(rq->avg_dl.util_avg);
3042 }
3043 
3044 
3045 extern unsigned long cpu_util_cfs(int cpu);
3046 extern unsigned long cpu_util_cfs_boost(int cpu);
3047 
3048 static inline unsigned long cpu_util_rt(struct rq *rq)
3049 {
3050 	return READ_ONCE(rq->avg_rt.util_avg);
3051 }
3052 #endif
3053 
3054 #ifdef CONFIG_UCLAMP_TASK
3055 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
3056 
3057 static inline unsigned long uclamp_rq_get(struct rq *rq,
3058 					  enum uclamp_id clamp_id)
3059 {
3060 	return READ_ONCE(rq->uclamp[clamp_id].value);
3061 }
3062 
3063 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id,
3064 				 unsigned int value)
3065 {
3066 	WRITE_ONCE(rq->uclamp[clamp_id].value, value);
3067 }
3068 
3069 static inline bool uclamp_rq_is_idle(struct rq *rq)
3070 {
3071 	return rq->uclamp_flags & UCLAMP_FLAG_IDLE;
3072 }
3073 
3074 /* Is the rq being capped/throttled by uclamp_max? */
3075 static inline bool uclamp_rq_is_capped(struct rq *rq)
3076 {
3077 	unsigned long rq_util;
3078 	unsigned long max_util;
3079 
3080 	if (!static_branch_likely(&sched_uclamp_used))
3081 		return false;
3082 
3083 	rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq);
3084 	max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
3085 
3086 	return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util;
3087 }
3088 
3089 /*
3090  * When uclamp is compiled in, the aggregation at rq level is 'turned off'
3091  * by default in the fast path and only gets turned on once userspace performs
3092  * an operation that requires it.
3093  *
3094  * Returns true if userspace opted-in to use uclamp and aggregation at rq level
3095  * hence is active.
3096  */
3097 static inline bool uclamp_is_used(void)
3098 {
3099 	return static_branch_likely(&sched_uclamp_used);
3100 }
3101 #else /* CONFIG_UCLAMP_TASK */
3102 static inline unsigned long uclamp_eff_value(struct task_struct *p,
3103 					     enum uclamp_id clamp_id)
3104 {
3105 	if (clamp_id == UCLAMP_MIN)
3106 		return 0;
3107 
3108 	return SCHED_CAPACITY_SCALE;
3109 }
3110 
3111 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; }
3112 
3113 static inline bool uclamp_is_used(void)
3114 {
3115 	return false;
3116 }
3117 
3118 static inline unsigned long uclamp_rq_get(struct rq *rq,
3119 					  enum uclamp_id clamp_id)
3120 {
3121 	if (clamp_id == UCLAMP_MIN)
3122 		return 0;
3123 
3124 	return SCHED_CAPACITY_SCALE;
3125 }
3126 
3127 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id,
3128 				 unsigned int value)
3129 {
3130 }
3131 
3132 static inline bool uclamp_rq_is_idle(struct rq *rq)
3133 {
3134 	return false;
3135 }
3136 #endif /* CONFIG_UCLAMP_TASK */
3137 
3138 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
3139 static inline unsigned long cpu_util_irq(struct rq *rq)
3140 {
3141 	return READ_ONCE(rq->avg_irq.util_avg);
3142 }
3143 
3144 static inline
3145 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3146 {
3147 	util *= (max - irq);
3148 	util /= max;
3149 
3150 	return util;
3151 
3152 }
3153 #else
3154 static inline unsigned long cpu_util_irq(struct rq *rq)
3155 {
3156 	return 0;
3157 }
3158 
3159 static inline
3160 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3161 {
3162 	return util;
3163 }
3164 #endif
3165 
3166 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
3167 
3168 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
3169 
3170 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
3171 
3172 static inline bool sched_energy_enabled(void)
3173 {
3174 	return static_branch_unlikely(&sched_energy_present);
3175 }
3176 
3177 extern struct cpufreq_governor schedutil_gov;
3178 
3179 #else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
3180 
3181 #define perf_domain_span(pd) NULL
3182 static inline bool sched_energy_enabled(void) { return false; }
3183 
3184 #endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
3185 
3186 #ifdef CONFIG_MEMBARRIER
3187 /*
3188  * The scheduler provides memory barriers required by membarrier between:
3189  * - prior user-space memory accesses and store to rq->membarrier_state,
3190  * - store to rq->membarrier_state and following user-space memory accesses.
3191  * In the same way it provides those guarantees around store to rq->curr.
3192  */
3193 static inline void membarrier_switch_mm(struct rq *rq,
3194 					struct mm_struct *prev_mm,
3195 					struct mm_struct *next_mm)
3196 {
3197 	int membarrier_state;
3198 
3199 	if (prev_mm == next_mm)
3200 		return;
3201 
3202 	membarrier_state = atomic_read(&next_mm->membarrier_state);
3203 	if (READ_ONCE(rq->membarrier_state) == membarrier_state)
3204 		return;
3205 
3206 	WRITE_ONCE(rq->membarrier_state, membarrier_state);
3207 }
3208 #else
3209 static inline void membarrier_switch_mm(struct rq *rq,
3210 					struct mm_struct *prev_mm,
3211 					struct mm_struct *next_mm)
3212 {
3213 }
3214 #endif
3215 
3216 #ifdef CONFIG_SMP
3217 static inline bool is_per_cpu_kthread(struct task_struct *p)
3218 {
3219 	if (!(p->flags & PF_KTHREAD))
3220 		return false;
3221 
3222 	if (p->nr_cpus_allowed != 1)
3223 		return false;
3224 
3225 	return true;
3226 }
3227 #endif
3228 
3229 extern void swake_up_all_locked(struct swait_queue_head *q);
3230 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
3231 
3232 extern int try_to_wake_up(struct task_struct *tsk, unsigned int state, int wake_flags);
3233 
3234 #ifdef CONFIG_PREEMPT_DYNAMIC
3235 extern int preempt_dynamic_mode;
3236 extern int sched_dynamic_mode(const char *str);
3237 extern void sched_dynamic_update(int mode);
3238 #endif
3239 
3240 #ifdef CONFIG_SCHED_MM_CID
3241 
3242 #define SCHED_MM_CID_PERIOD_NS	(100ULL * 1000000)	/* 100ms */
3243 #define MM_CID_SCAN_DELAY	100			/* 100ms */
3244 
3245 extern raw_spinlock_t cid_lock;
3246 extern int use_cid_lock;
3247 
3248 extern void sched_mm_cid_migrate_from(struct task_struct *t);
3249 extern void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t);
3250 extern void task_tick_mm_cid(struct rq *rq, struct task_struct *curr);
3251 extern void init_sched_mm_cid(struct task_struct *t);
3252 
3253 static inline void __mm_cid_put(struct mm_struct *mm, int cid)
3254 {
3255 	if (cid < 0)
3256 		return;
3257 	cpumask_clear_cpu(cid, mm_cidmask(mm));
3258 }
3259 
3260 /*
3261  * The per-mm/cpu cid can have the MM_CID_LAZY_PUT flag set or transition to
3262  * the MM_CID_UNSET state without holding the rq lock, but the rq lock needs to
3263  * be held to transition to other states.
3264  *
3265  * State transitions synchronized with cmpxchg or try_cmpxchg need to be
3266  * consistent across cpus, which prevents use of this_cpu_cmpxchg.
3267  */
3268 static inline void mm_cid_put_lazy(struct task_struct *t)
3269 {
3270 	struct mm_struct *mm = t->mm;
3271 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3272 	int cid;
3273 
3274 	lockdep_assert_irqs_disabled();
3275 	cid = __this_cpu_read(pcpu_cid->cid);
3276 	if (!mm_cid_is_lazy_put(cid) ||
3277 	    !try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET))
3278 		return;
3279 	__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3280 }
3281 
3282 static inline int mm_cid_pcpu_unset(struct mm_struct *mm)
3283 {
3284 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3285 	int cid, res;
3286 
3287 	lockdep_assert_irqs_disabled();
3288 	cid = __this_cpu_read(pcpu_cid->cid);
3289 	for (;;) {
3290 		if (mm_cid_is_unset(cid))
3291 			return MM_CID_UNSET;
3292 		/*
3293 		 * Attempt transition from valid or lazy-put to unset.
3294 		 */
3295 		res = cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, cid, MM_CID_UNSET);
3296 		if (res == cid)
3297 			break;
3298 		cid = res;
3299 	}
3300 	return cid;
3301 }
3302 
3303 static inline void mm_cid_put(struct mm_struct *mm)
3304 {
3305 	int cid;
3306 
3307 	lockdep_assert_irqs_disabled();
3308 	cid = mm_cid_pcpu_unset(mm);
3309 	if (cid == MM_CID_UNSET)
3310 		return;
3311 	__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3312 }
3313 
3314 static inline int __mm_cid_try_get(struct mm_struct *mm)
3315 {
3316 	struct cpumask *cpumask;
3317 	int cid;
3318 
3319 	cpumask = mm_cidmask(mm);
3320 	/*
3321 	 * Retry finding first zero bit if the mask is temporarily
3322 	 * filled. This only happens during concurrent remote-clear
3323 	 * which owns a cid without holding a rq lock.
3324 	 */
3325 	for (;;) {
3326 		cid = cpumask_first_zero(cpumask);
3327 		if (cid < nr_cpu_ids)
3328 			break;
3329 		cpu_relax();
3330 	}
3331 	if (cpumask_test_and_set_cpu(cid, cpumask))
3332 		return -1;
3333 	return cid;
3334 }
3335 
3336 /*
3337  * Save a snapshot of the current runqueue time of this cpu
3338  * with the per-cpu cid value, allowing to estimate how recently it was used.
3339  */
3340 static inline void mm_cid_snapshot_time(struct rq *rq, struct mm_struct *mm)
3341 {
3342 	struct mm_cid *pcpu_cid = per_cpu_ptr(mm->pcpu_cid, cpu_of(rq));
3343 
3344 	lockdep_assert_rq_held(rq);
3345 	WRITE_ONCE(pcpu_cid->time, rq->clock);
3346 }
3347 
3348 static inline int __mm_cid_get(struct rq *rq, struct mm_struct *mm)
3349 {
3350 	int cid;
3351 
3352 	/*
3353 	 * All allocations (even those using the cid_lock) are lock-free. If
3354 	 * use_cid_lock is set, hold the cid_lock to perform cid allocation to
3355 	 * guarantee forward progress.
3356 	 */
3357 	if (!READ_ONCE(use_cid_lock)) {
3358 		cid = __mm_cid_try_get(mm);
3359 		if (cid >= 0)
3360 			goto end;
3361 		raw_spin_lock(&cid_lock);
3362 	} else {
3363 		raw_spin_lock(&cid_lock);
3364 		cid = __mm_cid_try_get(mm);
3365 		if (cid >= 0)
3366 			goto unlock;
3367 	}
3368 
3369 	/*
3370 	 * cid concurrently allocated. Retry while forcing following
3371 	 * allocations to use the cid_lock to ensure forward progress.
3372 	 */
3373 	WRITE_ONCE(use_cid_lock, 1);
3374 	/*
3375 	 * Set use_cid_lock before allocation. Only care about program order
3376 	 * because this is only required for forward progress.
3377 	 */
3378 	barrier();
3379 	/*
3380 	 * Retry until it succeeds. It is guaranteed to eventually succeed once
3381 	 * all newcoming allocations observe the use_cid_lock flag set.
3382 	 */
3383 	do {
3384 		cid = __mm_cid_try_get(mm);
3385 		cpu_relax();
3386 	} while (cid < 0);
3387 	/*
3388 	 * Allocate before clearing use_cid_lock. Only care about
3389 	 * program order because this is for forward progress.
3390 	 */
3391 	barrier();
3392 	WRITE_ONCE(use_cid_lock, 0);
3393 unlock:
3394 	raw_spin_unlock(&cid_lock);
3395 end:
3396 	mm_cid_snapshot_time(rq, mm);
3397 	return cid;
3398 }
3399 
3400 static inline int mm_cid_get(struct rq *rq, struct mm_struct *mm)
3401 {
3402 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3403 	struct cpumask *cpumask;
3404 	int cid;
3405 
3406 	lockdep_assert_rq_held(rq);
3407 	cpumask = mm_cidmask(mm);
3408 	cid = __this_cpu_read(pcpu_cid->cid);
3409 	if (mm_cid_is_valid(cid)) {
3410 		mm_cid_snapshot_time(rq, mm);
3411 		return cid;
3412 	}
3413 	if (mm_cid_is_lazy_put(cid)) {
3414 		if (try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET))
3415 			__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3416 	}
3417 	cid = __mm_cid_get(rq, mm);
3418 	__this_cpu_write(pcpu_cid->cid, cid);
3419 	return cid;
3420 }
3421 
3422 static inline void switch_mm_cid(struct rq *rq,
3423 				 struct task_struct *prev,
3424 				 struct task_struct *next)
3425 {
3426 	/*
3427 	 * Provide a memory barrier between rq->curr store and load of
3428 	 * {prev,next}->mm->pcpu_cid[cpu] on rq->curr->mm transition.
3429 	 *
3430 	 * Should be adapted if context_switch() is modified.
3431 	 */
3432 	if (!next->mm) {                                // to kernel
3433 		/*
3434 		 * user -> kernel transition does not guarantee a barrier, but
3435 		 * we can use the fact that it performs an atomic operation in
3436 		 * mmgrab().
3437 		 */
3438 		if (prev->mm)                           // from user
3439 			smp_mb__after_mmgrab();
3440 		/*
3441 		 * kernel -> kernel transition does not change rq->curr->mm
3442 		 * state. It stays NULL.
3443 		 */
3444 	} else {                                        // to user
3445 		/*
3446 		 * kernel -> user transition does not provide a barrier
3447 		 * between rq->curr store and load of {prev,next}->mm->pcpu_cid[cpu].
3448 		 * Provide it here.
3449 		 */
3450 		if (!prev->mm) {                        // from kernel
3451 			smp_mb();
3452 		} else {				// from user
3453 			/*
3454 			 * user->user transition relies on an implicit
3455 			 * memory barrier in switch_mm() when
3456 			 * current->mm changes. If the architecture
3457 			 * switch_mm() does not have an implicit memory
3458 			 * barrier, it is emitted here.  If current->mm
3459 			 * is unchanged, no barrier is needed.
3460 			 */
3461 			smp_mb__after_switch_mm();
3462 		}
3463 	}
3464 	if (prev->mm_cid_active) {
3465 		mm_cid_snapshot_time(rq, prev->mm);
3466 		mm_cid_put_lazy(prev);
3467 		prev->mm_cid = -1;
3468 	}
3469 	if (next->mm_cid_active)
3470 		next->last_mm_cid = next->mm_cid = mm_cid_get(rq, next->mm);
3471 }
3472 
3473 #else
3474 static inline void switch_mm_cid(struct rq *rq, struct task_struct *prev, struct task_struct *next) { }
3475 static inline void sched_mm_cid_migrate_from(struct task_struct *t) { }
3476 static inline void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t) { }
3477 static inline void task_tick_mm_cid(struct rq *rq, struct task_struct *curr) { }
3478 static inline void init_sched_mm_cid(struct task_struct *t) { }
3479 #endif
3480 
3481 extern u64 avg_vruntime(struct cfs_rq *cfs_rq);
3482 extern int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se);
3483 
3484 #endif /* _KERNEL_SCHED_SCHED_H */
3485