xref: /openbmc/linux/kernel/sched/sched.h (revision aaeb31c0)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Scheduler internal types and methods:
4  */
5 #ifndef _KERNEL_SCHED_SCHED_H
6 #define _KERNEL_SCHED_SCHED_H
7 
8 #include <linux/sched/affinity.h>
9 #include <linux/sched/autogroup.h>
10 #include <linux/sched/cpufreq.h>
11 #include <linux/sched/deadline.h>
12 #include <linux/sched.h>
13 #include <linux/sched/loadavg.h>
14 #include <linux/sched/mm.h>
15 #include <linux/sched/rseq_api.h>
16 #include <linux/sched/signal.h>
17 #include <linux/sched/smt.h>
18 #include <linux/sched/stat.h>
19 #include <linux/sched/sysctl.h>
20 #include <linux/sched/task_flags.h>
21 #include <linux/sched/task.h>
22 #include <linux/sched/topology.h>
23 
24 #include <linux/atomic.h>
25 #include <linux/bitmap.h>
26 #include <linux/bug.h>
27 #include <linux/capability.h>
28 #include <linux/cgroup_api.h>
29 #include <linux/cgroup.h>
30 #include <linux/context_tracking.h>
31 #include <linux/cpufreq.h>
32 #include <linux/cpumask_api.h>
33 #include <linux/ctype.h>
34 #include <linux/file.h>
35 #include <linux/fs_api.h>
36 #include <linux/hrtimer_api.h>
37 #include <linux/interrupt.h>
38 #include <linux/irq_work.h>
39 #include <linux/jiffies.h>
40 #include <linux/kref_api.h>
41 #include <linux/kthread.h>
42 #include <linux/ktime_api.h>
43 #include <linux/lockdep_api.h>
44 #include <linux/lockdep.h>
45 #include <linux/minmax.h>
46 #include <linux/mm.h>
47 #include <linux/module.h>
48 #include <linux/mutex_api.h>
49 #include <linux/plist.h>
50 #include <linux/poll.h>
51 #include <linux/proc_fs.h>
52 #include <linux/profile.h>
53 #include <linux/psi.h>
54 #include <linux/rcupdate.h>
55 #include <linux/seq_file.h>
56 #include <linux/seqlock.h>
57 #include <linux/softirq.h>
58 #include <linux/spinlock_api.h>
59 #include <linux/static_key.h>
60 #include <linux/stop_machine.h>
61 #include <linux/syscalls_api.h>
62 #include <linux/syscalls.h>
63 #include <linux/tick.h>
64 #include <linux/topology.h>
65 #include <linux/types.h>
66 #include <linux/u64_stats_sync_api.h>
67 #include <linux/uaccess.h>
68 #include <linux/wait_api.h>
69 #include <linux/wait_bit.h>
70 #include <linux/workqueue_api.h>
71 
72 #include <trace/events/power.h>
73 #include <trace/events/sched.h>
74 
75 #include "../workqueue_internal.h"
76 
77 #ifdef CONFIG_CGROUP_SCHED
78 #include <linux/cgroup.h>
79 #include <linux/psi.h>
80 #endif
81 
82 #ifdef CONFIG_SCHED_DEBUG
83 # include <linux/static_key.h>
84 #endif
85 
86 #ifdef CONFIG_PARAVIRT
87 # include <asm/paravirt.h>
88 # include <asm/paravirt_api_clock.h>
89 #endif
90 
91 #include "cpupri.h"
92 #include "cpudeadline.h"
93 
94 #ifdef CONFIG_SCHED_DEBUG
95 # define SCHED_WARN_ON(x)      WARN_ONCE(x, #x)
96 #else
97 # define SCHED_WARN_ON(x)      ({ (void)(x), 0; })
98 #endif
99 
100 struct rq;
101 struct cpuidle_state;
102 
103 /* task_struct::on_rq states: */
104 #define TASK_ON_RQ_QUEUED	1
105 #define TASK_ON_RQ_MIGRATING	2
106 
107 extern __read_mostly int scheduler_running;
108 
109 extern unsigned long calc_load_update;
110 extern atomic_long_t calc_load_tasks;
111 
112 extern unsigned int sysctl_sched_child_runs_first;
113 
114 extern void calc_global_load_tick(struct rq *this_rq);
115 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
116 
117 extern void call_trace_sched_update_nr_running(struct rq *rq, int count);
118 
119 extern unsigned int sysctl_sched_rt_period;
120 extern int sysctl_sched_rt_runtime;
121 extern int sched_rr_timeslice;
122 
123 /*
124  * Helpers for converting nanosecond timing to jiffy resolution
125  */
126 #define NS_TO_JIFFIES(TIME)	((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
127 
128 /*
129  * Increase resolution of nice-level calculations for 64-bit architectures.
130  * The extra resolution improves shares distribution and load balancing of
131  * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
132  * hierarchies, especially on larger systems. This is not a user-visible change
133  * and does not change the user-interface for setting shares/weights.
134  *
135  * We increase resolution only if we have enough bits to allow this increased
136  * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
137  * are pretty high and the returns do not justify the increased costs.
138  *
139  * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
140  * increase coverage and consistency always enable it on 64-bit platforms.
141  */
142 #ifdef CONFIG_64BIT
143 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
144 # define scale_load(w)		((w) << SCHED_FIXEDPOINT_SHIFT)
145 # define scale_load_down(w) \
146 ({ \
147 	unsigned long __w = (w); \
148 	if (__w) \
149 		__w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \
150 	__w; \
151 })
152 #else
153 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT)
154 # define scale_load(w)		(w)
155 # define scale_load_down(w)	(w)
156 #endif
157 
158 /*
159  * Task weight (visible to users) and its load (invisible to users) have
160  * independent resolution, but they should be well calibrated. We use
161  * scale_load() and scale_load_down(w) to convert between them. The
162  * following must be true:
163  *
164  *  scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD
165  *
166  */
167 #define NICE_0_LOAD		(1L << NICE_0_LOAD_SHIFT)
168 
169 /*
170  * Single value that decides SCHED_DEADLINE internal math precision.
171  * 10 -> just above 1us
172  * 9  -> just above 0.5us
173  */
174 #define DL_SCALE		10
175 
176 /*
177  * Single value that denotes runtime == period, ie unlimited time.
178  */
179 #define RUNTIME_INF		((u64)~0ULL)
180 
181 static inline int idle_policy(int policy)
182 {
183 	return policy == SCHED_IDLE;
184 }
185 static inline int fair_policy(int policy)
186 {
187 	return policy == SCHED_NORMAL || policy == SCHED_BATCH;
188 }
189 
190 static inline int rt_policy(int policy)
191 {
192 	return policy == SCHED_FIFO || policy == SCHED_RR;
193 }
194 
195 static inline int dl_policy(int policy)
196 {
197 	return policy == SCHED_DEADLINE;
198 }
199 static inline bool valid_policy(int policy)
200 {
201 	return idle_policy(policy) || fair_policy(policy) ||
202 		rt_policy(policy) || dl_policy(policy);
203 }
204 
205 static inline int task_has_idle_policy(struct task_struct *p)
206 {
207 	return idle_policy(p->policy);
208 }
209 
210 static inline int task_has_rt_policy(struct task_struct *p)
211 {
212 	return rt_policy(p->policy);
213 }
214 
215 static inline int task_has_dl_policy(struct task_struct *p)
216 {
217 	return dl_policy(p->policy);
218 }
219 
220 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
221 
222 static inline void update_avg(u64 *avg, u64 sample)
223 {
224 	s64 diff = sample - *avg;
225 	*avg += diff / 8;
226 }
227 
228 /*
229  * Shifting a value by an exponent greater *or equal* to the size of said value
230  * is UB; cap at size-1.
231  */
232 #define shr_bound(val, shift)							\
233 	(val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1))
234 
235 /*
236  * !! For sched_setattr_nocheck() (kernel) only !!
237  *
238  * This is actually gross. :(
239  *
240  * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
241  * tasks, but still be able to sleep. We need this on platforms that cannot
242  * atomically change clock frequency. Remove once fast switching will be
243  * available on such platforms.
244  *
245  * SUGOV stands for SchedUtil GOVernor.
246  */
247 #define SCHED_FLAG_SUGOV	0x10000000
248 
249 #define SCHED_DL_FLAGS (SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV)
250 
251 static inline bool dl_entity_is_special(const struct sched_dl_entity *dl_se)
252 {
253 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
254 	return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
255 #else
256 	return false;
257 #endif
258 }
259 
260 /*
261  * Tells if entity @a should preempt entity @b.
262  */
263 static inline bool dl_entity_preempt(const struct sched_dl_entity *a,
264 				     const struct sched_dl_entity *b)
265 {
266 	return dl_entity_is_special(a) ||
267 	       dl_time_before(a->deadline, b->deadline);
268 }
269 
270 /*
271  * This is the priority-queue data structure of the RT scheduling class:
272  */
273 struct rt_prio_array {
274 	DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
275 	struct list_head queue[MAX_RT_PRIO];
276 };
277 
278 struct rt_bandwidth {
279 	/* nests inside the rq lock: */
280 	raw_spinlock_t		rt_runtime_lock;
281 	ktime_t			rt_period;
282 	u64			rt_runtime;
283 	struct hrtimer		rt_period_timer;
284 	unsigned int		rt_period_active;
285 };
286 
287 void __dl_clear_params(struct task_struct *p);
288 
289 struct dl_bandwidth {
290 	raw_spinlock_t		dl_runtime_lock;
291 	u64			dl_runtime;
292 	u64			dl_period;
293 };
294 
295 static inline int dl_bandwidth_enabled(void)
296 {
297 	return sysctl_sched_rt_runtime >= 0;
298 }
299 
300 /*
301  * To keep the bandwidth of -deadline tasks under control
302  * we need some place where:
303  *  - store the maximum -deadline bandwidth of each cpu;
304  *  - cache the fraction of bandwidth that is currently allocated in
305  *    each root domain;
306  *
307  * This is all done in the data structure below. It is similar to the
308  * one used for RT-throttling (rt_bandwidth), with the main difference
309  * that, since here we are only interested in admission control, we
310  * do not decrease any runtime while the group "executes", neither we
311  * need a timer to replenish it.
312  *
313  * With respect to SMP, bandwidth is given on a per root domain basis,
314  * meaning that:
315  *  - bw (< 100%) is the deadline bandwidth of each CPU;
316  *  - total_bw is the currently allocated bandwidth in each root domain;
317  */
318 struct dl_bw {
319 	raw_spinlock_t		lock;
320 	u64			bw;
321 	u64			total_bw;
322 };
323 
324 extern void init_dl_bw(struct dl_bw *dl_b);
325 extern int  sched_dl_global_validate(void);
326 extern void sched_dl_do_global(void);
327 extern int  sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
328 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
329 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
330 extern bool __checkparam_dl(const struct sched_attr *attr);
331 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
332 extern int  dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
333 extern int  dl_cpu_busy(int cpu, struct task_struct *p);
334 
335 #ifdef CONFIG_CGROUP_SCHED
336 
337 struct cfs_rq;
338 struct rt_rq;
339 
340 extern struct list_head task_groups;
341 
342 struct cfs_bandwidth {
343 #ifdef CONFIG_CFS_BANDWIDTH
344 	raw_spinlock_t		lock;
345 	ktime_t			period;
346 	u64			quota;
347 	u64			runtime;
348 	u64			burst;
349 	u64			runtime_snap;
350 	s64			hierarchical_quota;
351 
352 	u8			idle;
353 	u8			period_active;
354 	u8			slack_started;
355 	struct hrtimer		period_timer;
356 	struct hrtimer		slack_timer;
357 	struct list_head	throttled_cfs_rq;
358 
359 	/* Statistics: */
360 	int			nr_periods;
361 	int			nr_throttled;
362 	int			nr_burst;
363 	u64			throttled_time;
364 	u64			burst_time;
365 #endif
366 };
367 
368 /* Task group related information */
369 struct task_group {
370 	struct cgroup_subsys_state css;
371 
372 #ifdef CONFIG_FAIR_GROUP_SCHED
373 	/* schedulable entities of this group on each CPU */
374 	struct sched_entity	**se;
375 	/* runqueue "owned" by this group on each CPU */
376 	struct cfs_rq		**cfs_rq;
377 	unsigned long		shares;
378 
379 	/* A positive value indicates that this is a SCHED_IDLE group. */
380 	int			idle;
381 
382 #ifdef	CONFIG_SMP
383 	/*
384 	 * load_avg can be heavily contended at clock tick time, so put
385 	 * it in its own cacheline separated from the fields above which
386 	 * will also be accessed at each tick.
387 	 */
388 	atomic_long_t		load_avg ____cacheline_aligned;
389 #endif
390 #endif
391 
392 #ifdef CONFIG_RT_GROUP_SCHED
393 	struct sched_rt_entity	**rt_se;
394 	struct rt_rq		**rt_rq;
395 
396 	struct rt_bandwidth	rt_bandwidth;
397 #endif
398 
399 	struct rcu_head		rcu;
400 	struct list_head	list;
401 
402 	struct task_group	*parent;
403 	struct list_head	siblings;
404 	struct list_head	children;
405 
406 #ifdef CONFIG_SCHED_AUTOGROUP
407 	struct autogroup	*autogroup;
408 #endif
409 
410 	struct cfs_bandwidth	cfs_bandwidth;
411 
412 #ifdef CONFIG_UCLAMP_TASK_GROUP
413 	/* The two decimal precision [%] value requested from user-space */
414 	unsigned int		uclamp_pct[UCLAMP_CNT];
415 	/* Clamp values requested for a task group */
416 	struct uclamp_se	uclamp_req[UCLAMP_CNT];
417 	/* Effective clamp values used for a task group */
418 	struct uclamp_se	uclamp[UCLAMP_CNT];
419 #endif
420 
421 };
422 
423 #ifdef CONFIG_FAIR_GROUP_SCHED
424 #define ROOT_TASK_GROUP_LOAD	NICE_0_LOAD
425 
426 /*
427  * A weight of 0 or 1 can cause arithmetics problems.
428  * A weight of a cfs_rq is the sum of weights of which entities
429  * are queued on this cfs_rq, so a weight of a entity should not be
430  * too large, so as the shares value of a task group.
431  * (The default weight is 1024 - so there's no practical
432  *  limitation from this.)
433  */
434 #define MIN_SHARES		(1UL <<  1)
435 #define MAX_SHARES		(1UL << 18)
436 #endif
437 
438 typedef int (*tg_visitor)(struct task_group *, void *);
439 
440 extern int walk_tg_tree_from(struct task_group *from,
441 			     tg_visitor down, tg_visitor up, void *data);
442 
443 /*
444  * Iterate the full tree, calling @down when first entering a node and @up when
445  * leaving it for the final time.
446  *
447  * Caller must hold rcu_lock or sufficient equivalent.
448  */
449 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
450 {
451 	return walk_tg_tree_from(&root_task_group, down, up, data);
452 }
453 
454 extern int tg_nop(struct task_group *tg, void *data);
455 
456 extern void free_fair_sched_group(struct task_group *tg);
457 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
458 extern void online_fair_sched_group(struct task_group *tg);
459 extern void unregister_fair_sched_group(struct task_group *tg);
460 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
461 			struct sched_entity *se, int cpu,
462 			struct sched_entity *parent);
463 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
464 
465 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
466 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
467 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
468 
469 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
470 		struct sched_rt_entity *rt_se, int cpu,
471 		struct sched_rt_entity *parent);
472 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
473 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
474 extern long sched_group_rt_runtime(struct task_group *tg);
475 extern long sched_group_rt_period(struct task_group *tg);
476 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
477 
478 extern struct task_group *sched_create_group(struct task_group *parent);
479 extern void sched_online_group(struct task_group *tg,
480 			       struct task_group *parent);
481 extern void sched_destroy_group(struct task_group *tg);
482 extern void sched_release_group(struct task_group *tg);
483 
484 extern void sched_move_task(struct task_struct *tsk);
485 
486 #ifdef CONFIG_FAIR_GROUP_SCHED
487 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
488 
489 extern int sched_group_set_idle(struct task_group *tg, long idle);
490 
491 #ifdef CONFIG_SMP
492 extern void set_task_rq_fair(struct sched_entity *se,
493 			     struct cfs_rq *prev, struct cfs_rq *next);
494 #else /* !CONFIG_SMP */
495 static inline void set_task_rq_fair(struct sched_entity *se,
496 			     struct cfs_rq *prev, struct cfs_rq *next) { }
497 #endif /* CONFIG_SMP */
498 #endif /* CONFIG_FAIR_GROUP_SCHED */
499 
500 #else /* CONFIG_CGROUP_SCHED */
501 
502 struct cfs_bandwidth { };
503 
504 #endif	/* CONFIG_CGROUP_SCHED */
505 
506 extern void unregister_rt_sched_group(struct task_group *tg);
507 extern void free_rt_sched_group(struct task_group *tg);
508 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
509 
510 /*
511  * u64_u32_load/u64_u32_store
512  *
513  * Use a copy of a u64 value to protect against data race. This is only
514  * applicable for 32-bits architectures.
515  */
516 #ifdef CONFIG_64BIT
517 # define u64_u32_load_copy(var, copy)       var
518 # define u64_u32_store_copy(var, copy, val) (var = val)
519 #else
520 # define u64_u32_load_copy(var, copy)					\
521 ({									\
522 	u64 __val, __val_copy;						\
523 	do {								\
524 		__val_copy = copy;					\
525 		/*							\
526 		 * paired with u64_u32_store_copy(), ordering access	\
527 		 * to var and copy.					\
528 		 */							\
529 		smp_rmb();						\
530 		__val = var;						\
531 	} while (__val != __val_copy);					\
532 	__val;								\
533 })
534 # define u64_u32_store_copy(var, copy, val)				\
535 do {									\
536 	typeof(val) __val = (val);					\
537 	var = __val;							\
538 	/*								\
539 	 * paired with u64_u32_load_copy(), ordering access to var and	\
540 	 * copy.							\
541 	 */								\
542 	smp_wmb();							\
543 	copy = __val;							\
544 } while (0)
545 #endif
546 # define u64_u32_load(var)      u64_u32_load_copy(var, var##_copy)
547 # define u64_u32_store(var, val) u64_u32_store_copy(var, var##_copy, val)
548 
549 /* CFS-related fields in a runqueue */
550 struct cfs_rq {
551 	struct load_weight	load;
552 	unsigned int		nr_running;
553 	unsigned int		h_nr_running;      /* SCHED_{NORMAL,BATCH,IDLE} */
554 	unsigned int		idle_nr_running;   /* SCHED_IDLE */
555 	unsigned int		idle_h_nr_running; /* SCHED_IDLE */
556 
557 	u64			exec_clock;
558 	u64			min_vruntime;
559 #ifdef CONFIG_SCHED_CORE
560 	unsigned int		forceidle_seq;
561 	u64			min_vruntime_fi;
562 #endif
563 
564 #ifndef CONFIG_64BIT
565 	u64			min_vruntime_copy;
566 #endif
567 
568 	struct rb_root_cached	tasks_timeline;
569 
570 	/*
571 	 * 'curr' points to currently running entity on this cfs_rq.
572 	 * It is set to NULL otherwise (i.e when none are currently running).
573 	 */
574 	struct sched_entity	*curr;
575 	struct sched_entity	*next;
576 	struct sched_entity	*last;
577 	struct sched_entity	*skip;
578 
579 #ifdef	CONFIG_SCHED_DEBUG
580 	unsigned int		nr_spread_over;
581 #endif
582 
583 #ifdef CONFIG_SMP
584 	/*
585 	 * CFS load tracking
586 	 */
587 	struct sched_avg	avg;
588 #ifndef CONFIG_64BIT
589 	u64			last_update_time_copy;
590 #endif
591 	struct {
592 		raw_spinlock_t	lock ____cacheline_aligned;
593 		int		nr;
594 		unsigned long	load_avg;
595 		unsigned long	util_avg;
596 		unsigned long	runnable_avg;
597 	} removed;
598 
599 #ifdef CONFIG_FAIR_GROUP_SCHED
600 	unsigned long		tg_load_avg_contrib;
601 	long			propagate;
602 	long			prop_runnable_sum;
603 
604 	/*
605 	 *   h_load = weight * f(tg)
606 	 *
607 	 * Where f(tg) is the recursive weight fraction assigned to
608 	 * this group.
609 	 */
610 	unsigned long		h_load;
611 	u64			last_h_load_update;
612 	struct sched_entity	*h_load_next;
613 #endif /* CONFIG_FAIR_GROUP_SCHED */
614 #endif /* CONFIG_SMP */
615 
616 #ifdef CONFIG_FAIR_GROUP_SCHED
617 	struct rq		*rq;	/* CPU runqueue to which this cfs_rq is attached */
618 
619 	/*
620 	 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
621 	 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
622 	 * (like users, containers etc.)
623 	 *
624 	 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
625 	 * This list is used during load balance.
626 	 */
627 	int			on_list;
628 	struct list_head	leaf_cfs_rq_list;
629 	struct task_group	*tg;	/* group that "owns" this runqueue */
630 
631 	/* Locally cached copy of our task_group's idle value */
632 	int			idle;
633 
634 #ifdef CONFIG_CFS_BANDWIDTH
635 	int			runtime_enabled;
636 	s64			runtime_remaining;
637 
638 	u64			throttled_pelt_idle;
639 #ifndef CONFIG_64BIT
640 	u64                     throttled_pelt_idle_copy;
641 #endif
642 	u64			throttled_clock;
643 	u64			throttled_clock_pelt;
644 	u64			throttled_clock_pelt_time;
645 	int			throttled;
646 	int			throttle_count;
647 	struct list_head	throttled_list;
648 #ifdef CONFIG_SMP
649 	struct list_head	throttled_csd_list;
650 #endif
651 #endif /* CONFIG_CFS_BANDWIDTH */
652 #endif /* CONFIG_FAIR_GROUP_SCHED */
653 };
654 
655 static inline int rt_bandwidth_enabled(void)
656 {
657 	return sysctl_sched_rt_runtime >= 0;
658 }
659 
660 /* RT IPI pull logic requires IRQ_WORK */
661 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
662 # define HAVE_RT_PUSH_IPI
663 #endif
664 
665 /* Real-Time classes' related field in a runqueue: */
666 struct rt_rq {
667 	struct rt_prio_array	active;
668 	unsigned int		rt_nr_running;
669 	unsigned int		rr_nr_running;
670 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
671 	struct {
672 		int		curr; /* highest queued rt task prio */
673 #ifdef CONFIG_SMP
674 		int		next; /* next highest */
675 #endif
676 	} highest_prio;
677 #endif
678 #ifdef CONFIG_SMP
679 	unsigned int		rt_nr_migratory;
680 	unsigned int		rt_nr_total;
681 	int			overloaded;
682 	struct plist_head	pushable_tasks;
683 
684 #endif /* CONFIG_SMP */
685 	int			rt_queued;
686 
687 	int			rt_throttled;
688 	u64			rt_time;
689 	u64			rt_runtime;
690 	/* Nests inside the rq lock: */
691 	raw_spinlock_t		rt_runtime_lock;
692 
693 #ifdef CONFIG_RT_GROUP_SCHED
694 	unsigned int		rt_nr_boosted;
695 
696 	struct rq		*rq;
697 	struct task_group	*tg;
698 #endif
699 };
700 
701 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
702 {
703 	return rt_rq->rt_queued && rt_rq->rt_nr_running;
704 }
705 
706 /* Deadline class' related fields in a runqueue */
707 struct dl_rq {
708 	/* runqueue is an rbtree, ordered by deadline */
709 	struct rb_root_cached	root;
710 
711 	unsigned int		dl_nr_running;
712 
713 #ifdef CONFIG_SMP
714 	/*
715 	 * Deadline values of the currently executing and the
716 	 * earliest ready task on this rq. Caching these facilitates
717 	 * the decision whether or not a ready but not running task
718 	 * should migrate somewhere else.
719 	 */
720 	struct {
721 		u64		curr;
722 		u64		next;
723 	} earliest_dl;
724 
725 	unsigned int		dl_nr_migratory;
726 	int			overloaded;
727 
728 	/*
729 	 * Tasks on this rq that can be pushed away. They are kept in
730 	 * an rb-tree, ordered by tasks' deadlines, with caching
731 	 * of the leftmost (earliest deadline) element.
732 	 */
733 	struct rb_root_cached	pushable_dl_tasks_root;
734 #else
735 	struct dl_bw		dl_bw;
736 #endif
737 	/*
738 	 * "Active utilization" for this runqueue: increased when a
739 	 * task wakes up (becomes TASK_RUNNING) and decreased when a
740 	 * task blocks
741 	 */
742 	u64			running_bw;
743 
744 	/*
745 	 * Utilization of the tasks "assigned" to this runqueue (including
746 	 * the tasks that are in runqueue and the tasks that executed on this
747 	 * CPU and blocked). Increased when a task moves to this runqueue, and
748 	 * decreased when the task moves away (migrates, changes scheduling
749 	 * policy, or terminates).
750 	 * This is needed to compute the "inactive utilization" for the
751 	 * runqueue (inactive utilization = this_bw - running_bw).
752 	 */
753 	u64			this_bw;
754 	u64			extra_bw;
755 
756 	/*
757 	 * Inverse of the fraction of CPU utilization that can be reclaimed
758 	 * by the GRUB algorithm.
759 	 */
760 	u64			bw_ratio;
761 };
762 
763 #ifdef CONFIG_FAIR_GROUP_SCHED
764 /* An entity is a task if it doesn't "own" a runqueue */
765 #define entity_is_task(se)	(!se->my_q)
766 
767 static inline void se_update_runnable(struct sched_entity *se)
768 {
769 	if (!entity_is_task(se))
770 		se->runnable_weight = se->my_q->h_nr_running;
771 }
772 
773 static inline long se_runnable(struct sched_entity *se)
774 {
775 	if (entity_is_task(se))
776 		return !!se->on_rq;
777 	else
778 		return se->runnable_weight;
779 }
780 
781 #else
782 #define entity_is_task(se)	1
783 
784 static inline void se_update_runnable(struct sched_entity *se) {}
785 
786 static inline long se_runnable(struct sched_entity *se)
787 {
788 	return !!se->on_rq;
789 }
790 #endif
791 
792 #ifdef CONFIG_SMP
793 /*
794  * XXX we want to get rid of these helpers and use the full load resolution.
795  */
796 static inline long se_weight(struct sched_entity *se)
797 {
798 	return scale_load_down(se->load.weight);
799 }
800 
801 
802 static inline bool sched_asym_prefer(int a, int b)
803 {
804 	return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
805 }
806 
807 struct perf_domain {
808 	struct em_perf_domain *em_pd;
809 	struct perf_domain *next;
810 	struct rcu_head rcu;
811 };
812 
813 /* Scheduling group status flags */
814 #define SG_OVERLOAD		0x1 /* More than one runnable task on a CPU. */
815 #define SG_OVERUTILIZED		0x2 /* One or more CPUs are over-utilized. */
816 
817 /*
818  * We add the notion of a root-domain which will be used to define per-domain
819  * variables. Each exclusive cpuset essentially defines an island domain by
820  * fully partitioning the member CPUs from any other cpuset. Whenever a new
821  * exclusive cpuset is created, we also create and attach a new root-domain
822  * object.
823  *
824  */
825 struct root_domain {
826 	atomic_t		refcount;
827 	atomic_t		rto_count;
828 	struct rcu_head		rcu;
829 	cpumask_var_t		span;
830 	cpumask_var_t		online;
831 
832 	/*
833 	 * Indicate pullable load on at least one CPU, e.g:
834 	 * - More than one runnable task
835 	 * - Running task is misfit
836 	 */
837 	int			overload;
838 
839 	/* Indicate one or more cpus over-utilized (tipping point) */
840 	int			overutilized;
841 
842 	/*
843 	 * The bit corresponding to a CPU gets set here if such CPU has more
844 	 * than one runnable -deadline task (as it is below for RT tasks).
845 	 */
846 	cpumask_var_t		dlo_mask;
847 	atomic_t		dlo_count;
848 	struct dl_bw		dl_bw;
849 	struct cpudl		cpudl;
850 
851 	/*
852 	 * Indicate whether a root_domain's dl_bw has been checked or
853 	 * updated. It's monotonously increasing value.
854 	 *
855 	 * Also, some corner cases, like 'wrap around' is dangerous, but given
856 	 * that u64 is 'big enough'. So that shouldn't be a concern.
857 	 */
858 	u64 visit_gen;
859 
860 #ifdef HAVE_RT_PUSH_IPI
861 	/*
862 	 * For IPI pull requests, loop across the rto_mask.
863 	 */
864 	struct irq_work		rto_push_work;
865 	raw_spinlock_t		rto_lock;
866 	/* These are only updated and read within rto_lock */
867 	int			rto_loop;
868 	int			rto_cpu;
869 	/* These atomics are updated outside of a lock */
870 	atomic_t		rto_loop_next;
871 	atomic_t		rto_loop_start;
872 #endif
873 	/*
874 	 * The "RT overload" flag: it gets set if a CPU has more than
875 	 * one runnable RT task.
876 	 */
877 	cpumask_var_t		rto_mask;
878 	struct cpupri		cpupri;
879 
880 	unsigned long		max_cpu_capacity;
881 
882 	/*
883 	 * NULL-terminated list of performance domains intersecting with the
884 	 * CPUs of the rd. Protected by RCU.
885 	 */
886 	struct perf_domain __rcu *pd;
887 };
888 
889 extern void init_defrootdomain(void);
890 extern int sched_init_domains(const struct cpumask *cpu_map);
891 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
892 extern void sched_get_rd(struct root_domain *rd);
893 extern void sched_put_rd(struct root_domain *rd);
894 
895 #ifdef HAVE_RT_PUSH_IPI
896 extern void rto_push_irq_work_func(struct irq_work *work);
897 #endif
898 #endif /* CONFIG_SMP */
899 
900 #ifdef CONFIG_UCLAMP_TASK
901 /*
902  * struct uclamp_bucket - Utilization clamp bucket
903  * @value: utilization clamp value for tasks on this clamp bucket
904  * @tasks: number of RUNNABLE tasks on this clamp bucket
905  *
906  * Keep track of how many tasks are RUNNABLE for a given utilization
907  * clamp value.
908  */
909 struct uclamp_bucket {
910 	unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
911 	unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
912 };
913 
914 /*
915  * struct uclamp_rq - rq's utilization clamp
916  * @value: currently active clamp values for a rq
917  * @bucket: utilization clamp buckets affecting a rq
918  *
919  * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
920  * A clamp value is affecting a rq when there is at least one task RUNNABLE
921  * (or actually running) with that value.
922  *
923  * There are up to UCLAMP_CNT possible different clamp values, currently there
924  * are only two: minimum utilization and maximum utilization.
925  *
926  * All utilization clamping values are MAX aggregated, since:
927  * - for util_min: we want to run the CPU at least at the max of the minimum
928  *   utilization required by its currently RUNNABLE tasks.
929  * - for util_max: we want to allow the CPU to run up to the max of the
930  *   maximum utilization allowed by its currently RUNNABLE tasks.
931  *
932  * Since on each system we expect only a limited number of different
933  * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
934  * the metrics required to compute all the per-rq utilization clamp values.
935  */
936 struct uclamp_rq {
937 	unsigned int value;
938 	struct uclamp_bucket bucket[UCLAMP_BUCKETS];
939 };
940 
941 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
942 #endif /* CONFIG_UCLAMP_TASK */
943 
944 struct rq;
945 struct balance_callback {
946 	struct balance_callback *next;
947 	void (*func)(struct rq *rq);
948 };
949 
950 /*
951  * This is the main, per-CPU runqueue data structure.
952  *
953  * Locking rule: those places that want to lock multiple runqueues
954  * (such as the load balancing or the thread migration code), lock
955  * acquire operations must be ordered by ascending &runqueue.
956  */
957 struct rq {
958 	/* runqueue lock: */
959 	raw_spinlock_t		__lock;
960 
961 	/*
962 	 * nr_running and cpu_load should be in the same cacheline because
963 	 * remote CPUs use both these fields when doing load calculation.
964 	 */
965 	unsigned int		nr_running;
966 #ifdef CONFIG_NUMA_BALANCING
967 	unsigned int		nr_numa_running;
968 	unsigned int		nr_preferred_running;
969 	unsigned int		numa_migrate_on;
970 #endif
971 #ifdef CONFIG_NO_HZ_COMMON
972 #ifdef CONFIG_SMP
973 	unsigned long		last_blocked_load_update_tick;
974 	unsigned int		has_blocked_load;
975 	call_single_data_t	nohz_csd;
976 #endif /* CONFIG_SMP */
977 	unsigned int		nohz_tick_stopped;
978 	atomic_t		nohz_flags;
979 #endif /* CONFIG_NO_HZ_COMMON */
980 
981 #ifdef CONFIG_SMP
982 	unsigned int		ttwu_pending;
983 #endif
984 	u64			nr_switches;
985 
986 #ifdef CONFIG_UCLAMP_TASK
987 	/* Utilization clamp values based on CPU's RUNNABLE tasks */
988 	struct uclamp_rq	uclamp[UCLAMP_CNT] ____cacheline_aligned;
989 	unsigned int		uclamp_flags;
990 #define UCLAMP_FLAG_IDLE 0x01
991 #endif
992 
993 	struct cfs_rq		cfs;
994 	struct rt_rq		rt;
995 	struct dl_rq		dl;
996 
997 #ifdef CONFIG_FAIR_GROUP_SCHED
998 	/* list of leaf cfs_rq on this CPU: */
999 	struct list_head	leaf_cfs_rq_list;
1000 	struct list_head	*tmp_alone_branch;
1001 #endif /* CONFIG_FAIR_GROUP_SCHED */
1002 
1003 	/*
1004 	 * This is part of a global counter where only the total sum
1005 	 * over all CPUs matters. A task can increase this counter on
1006 	 * one CPU and if it got migrated afterwards it may decrease
1007 	 * it on another CPU. Always updated under the runqueue lock:
1008 	 */
1009 	unsigned int		nr_uninterruptible;
1010 
1011 	struct task_struct __rcu	*curr;
1012 	struct task_struct	*idle;
1013 	struct task_struct	*stop;
1014 	unsigned long		next_balance;
1015 	struct mm_struct	*prev_mm;
1016 
1017 	unsigned int		clock_update_flags;
1018 	u64			clock;
1019 	/* Ensure that all clocks are in the same cache line */
1020 	u64			clock_task ____cacheline_aligned;
1021 	u64			clock_pelt;
1022 	unsigned long		lost_idle_time;
1023 	u64			clock_pelt_idle;
1024 	u64			clock_idle;
1025 #ifndef CONFIG_64BIT
1026 	u64			clock_pelt_idle_copy;
1027 	u64			clock_idle_copy;
1028 #endif
1029 
1030 	atomic_t		nr_iowait;
1031 
1032 #ifdef CONFIG_SCHED_DEBUG
1033 	u64 last_seen_need_resched_ns;
1034 	int ticks_without_resched;
1035 #endif
1036 
1037 #ifdef CONFIG_MEMBARRIER
1038 	int membarrier_state;
1039 #endif
1040 
1041 #ifdef CONFIG_SMP
1042 	struct root_domain		*rd;
1043 	struct sched_domain __rcu	*sd;
1044 
1045 	unsigned long		cpu_capacity;
1046 	unsigned long		cpu_capacity_orig;
1047 
1048 	struct balance_callback *balance_callback;
1049 
1050 	unsigned char		nohz_idle_balance;
1051 	unsigned char		idle_balance;
1052 
1053 	unsigned long		misfit_task_load;
1054 
1055 	/* For active balancing */
1056 	int			active_balance;
1057 	int			push_cpu;
1058 	struct cpu_stop_work	active_balance_work;
1059 
1060 	/* CPU of this runqueue: */
1061 	int			cpu;
1062 	int			online;
1063 
1064 	struct list_head cfs_tasks;
1065 
1066 	struct sched_avg	avg_rt;
1067 	struct sched_avg	avg_dl;
1068 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1069 	struct sched_avg	avg_irq;
1070 #endif
1071 #ifdef CONFIG_SCHED_THERMAL_PRESSURE
1072 	struct sched_avg	avg_thermal;
1073 #endif
1074 	u64			idle_stamp;
1075 	u64			avg_idle;
1076 
1077 	unsigned long		wake_stamp;
1078 	u64			wake_avg_idle;
1079 
1080 	/* This is used to determine avg_idle's max value */
1081 	u64			max_idle_balance_cost;
1082 
1083 #ifdef CONFIG_HOTPLUG_CPU
1084 	struct rcuwait		hotplug_wait;
1085 #endif
1086 #endif /* CONFIG_SMP */
1087 
1088 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1089 	u64			prev_irq_time;
1090 #endif
1091 #ifdef CONFIG_PARAVIRT
1092 	u64			prev_steal_time;
1093 #endif
1094 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1095 	u64			prev_steal_time_rq;
1096 #endif
1097 
1098 	/* calc_load related fields */
1099 	unsigned long		calc_load_update;
1100 	long			calc_load_active;
1101 
1102 #ifdef CONFIG_SCHED_HRTICK
1103 #ifdef CONFIG_SMP
1104 	call_single_data_t	hrtick_csd;
1105 #endif
1106 	struct hrtimer		hrtick_timer;
1107 	ktime_t 		hrtick_time;
1108 #endif
1109 
1110 #ifdef CONFIG_SCHEDSTATS
1111 	/* latency stats */
1112 	struct sched_info	rq_sched_info;
1113 	unsigned long long	rq_cpu_time;
1114 	/* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
1115 
1116 	/* sys_sched_yield() stats */
1117 	unsigned int		yld_count;
1118 
1119 	/* schedule() stats */
1120 	unsigned int		sched_count;
1121 	unsigned int		sched_goidle;
1122 
1123 	/* try_to_wake_up() stats */
1124 	unsigned int		ttwu_count;
1125 	unsigned int		ttwu_local;
1126 #endif
1127 
1128 #ifdef CONFIG_CPU_IDLE
1129 	/* Must be inspected within a rcu lock section */
1130 	struct cpuidle_state	*idle_state;
1131 #endif
1132 
1133 #ifdef CONFIG_SMP
1134 	unsigned int		nr_pinned;
1135 #endif
1136 	unsigned int		push_busy;
1137 	struct cpu_stop_work	push_work;
1138 
1139 #ifdef CONFIG_SCHED_CORE
1140 	/* per rq */
1141 	struct rq		*core;
1142 	struct task_struct	*core_pick;
1143 	unsigned int		core_enabled;
1144 	unsigned int		core_sched_seq;
1145 	struct rb_root		core_tree;
1146 
1147 	/* shared state -- careful with sched_core_cpu_deactivate() */
1148 	unsigned int		core_task_seq;
1149 	unsigned int		core_pick_seq;
1150 	unsigned long		core_cookie;
1151 	unsigned int		core_forceidle_count;
1152 	unsigned int		core_forceidle_seq;
1153 	unsigned int		core_forceidle_occupation;
1154 	u64			core_forceidle_start;
1155 #endif
1156 
1157 	/* Scratch cpumask to be temporarily used under rq_lock */
1158 	cpumask_var_t		scratch_mask;
1159 
1160 #if defined(CONFIG_CFS_BANDWIDTH) && defined(CONFIG_SMP)
1161 	call_single_data_t	cfsb_csd;
1162 	struct list_head	cfsb_csd_list;
1163 #endif
1164 };
1165 
1166 #ifdef CONFIG_FAIR_GROUP_SCHED
1167 
1168 /* CPU runqueue to which this cfs_rq is attached */
1169 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1170 {
1171 	return cfs_rq->rq;
1172 }
1173 
1174 #else
1175 
1176 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1177 {
1178 	return container_of(cfs_rq, struct rq, cfs);
1179 }
1180 #endif
1181 
1182 static inline int cpu_of(struct rq *rq)
1183 {
1184 #ifdef CONFIG_SMP
1185 	return rq->cpu;
1186 #else
1187 	return 0;
1188 #endif
1189 }
1190 
1191 #define MDF_PUSH	0x01
1192 
1193 static inline bool is_migration_disabled(struct task_struct *p)
1194 {
1195 #ifdef CONFIG_SMP
1196 	return p->migration_disabled;
1197 #else
1198 	return false;
1199 #endif
1200 }
1201 
1202 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1203 
1204 #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
1205 #define this_rq()		this_cpu_ptr(&runqueues)
1206 #define task_rq(p)		cpu_rq(task_cpu(p))
1207 #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
1208 #define raw_rq()		raw_cpu_ptr(&runqueues)
1209 
1210 struct sched_group;
1211 #ifdef CONFIG_SCHED_CORE
1212 static inline struct cpumask *sched_group_span(struct sched_group *sg);
1213 
1214 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled);
1215 
1216 static inline bool sched_core_enabled(struct rq *rq)
1217 {
1218 	return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled;
1219 }
1220 
1221 static inline bool sched_core_disabled(void)
1222 {
1223 	return !static_branch_unlikely(&__sched_core_enabled);
1224 }
1225 
1226 /*
1227  * Be careful with this function; not for general use. The return value isn't
1228  * stable unless you actually hold a relevant rq->__lock.
1229  */
1230 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1231 {
1232 	if (sched_core_enabled(rq))
1233 		return &rq->core->__lock;
1234 
1235 	return &rq->__lock;
1236 }
1237 
1238 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1239 {
1240 	if (rq->core_enabled)
1241 		return &rq->core->__lock;
1242 
1243 	return &rq->__lock;
1244 }
1245 
1246 bool cfs_prio_less(const struct task_struct *a, const struct task_struct *b,
1247 			bool fi);
1248 
1249 /*
1250  * Helpers to check if the CPU's core cookie matches with the task's cookie
1251  * when core scheduling is enabled.
1252  * A special case is that the task's cookie always matches with CPU's core
1253  * cookie if the CPU is in an idle core.
1254  */
1255 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1256 {
1257 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1258 	if (!sched_core_enabled(rq))
1259 		return true;
1260 
1261 	return rq->core->core_cookie == p->core_cookie;
1262 }
1263 
1264 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1265 {
1266 	bool idle_core = true;
1267 	int cpu;
1268 
1269 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1270 	if (!sched_core_enabled(rq))
1271 		return true;
1272 
1273 	for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) {
1274 		if (!available_idle_cpu(cpu)) {
1275 			idle_core = false;
1276 			break;
1277 		}
1278 	}
1279 
1280 	/*
1281 	 * A CPU in an idle core is always the best choice for tasks with
1282 	 * cookies.
1283 	 */
1284 	return idle_core || rq->core->core_cookie == p->core_cookie;
1285 }
1286 
1287 static inline bool sched_group_cookie_match(struct rq *rq,
1288 					    struct task_struct *p,
1289 					    struct sched_group *group)
1290 {
1291 	int cpu;
1292 
1293 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1294 	if (!sched_core_enabled(rq))
1295 		return true;
1296 
1297 	for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
1298 		if (sched_core_cookie_match(cpu_rq(cpu), p))
1299 			return true;
1300 	}
1301 	return false;
1302 }
1303 
1304 static inline bool sched_core_enqueued(struct task_struct *p)
1305 {
1306 	return !RB_EMPTY_NODE(&p->core_node);
1307 }
1308 
1309 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p);
1310 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags);
1311 
1312 extern void sched_core_get(void);
1313 extern void sched_core_put(void);
1314 
1315 #else /* !CONFIG_SCHED_CORE */
1316 
1317 static inline bool sched_core_enabled(struct rq *rq)
1318 {
1319 	return false;
1320 }
1321 
1322 static inline bool sched_core_disabled(void)
1323 {
1324 	return true;
1325 }
1326 
1327 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1328 {
1329 	return &rq->__lock;
1330 }
1331 
1332 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1333 {
1334 	return &rq->__lock;
1335 }
1336 
1337 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1338 {
1339 	return true;
1340 }
1341 
1342 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1343 {
1344 	return true;
1345 }
1346 
1347 static inline bool sched_group_cookie_match(struct rq *rq,
1348 					    struct task_struct *p,
1349 					    struct sched_group *group)
1350 {
1351 	return true;
1352 }
1353 #endif /* CONFIG_SCHED_CORE */
1354 
1355 static inline void lockdep_assert_rq_held(struct rq *rq)
1356 {
1357 	lockdep_assert_held(__rq_lockp(rq));
1358 }
1359 
1360 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass);
1361 extern bool raw_spin_rq_trylock(struct rq *rq);
1362 extern void raw_spin_rq_unlock(struct rq *rq);
1363 
1364 static inline void raw_spin_rq_lock(struct rq *rq)
1365 {
1366 	raw_spin_rq_lock_nested(rq, 0);
1367 }
1368 
1369 static inline void raw_spin_rq_lock_irq(struct rq *rq)
1370 {
1371 	local_irq_disable();
1372 	raw_spin_rq_lock(rq);
1373 }
1374 
1375 static inline void raw_spin_rq_unlock_irq(struct rq *rq)
1376 {
1377 	raw_spin_rq_unlock(rq);
1378 	local_irq_enable();
1379 }
1380 
1381 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq)
1382 {
1383 	unsigned long flags;
1384 	local_irq_save(flags);
1385 	raw_spin_rq_lock(rq);
1386 	return flags;
1387 }
1388 
1389 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags)
1390 {
1391 	raw_spin_rq_unlock(rq);
1392 	local_irq_restore(flags);
1393 }
1394 
1395 #define raw_spin_rq_lock_irqsave(rq, flags)	\
1396 do {						\
1397 	flags = _raw_spin_rq_lock_irqsave(rq);	\
1398 } while (0)
1399 
1400 #ifdef CONFIG_SCHED_SMT
1401 extern void __update_idle_core(struct rq *rq);
1402 
1403 static inline void update_idle_core(struct rq *rq)
1404 {
1405 	if (static_branch_unlikely(&sched_smt_present))
1406 		__update_idle_core(rq);
1407 }
1408 
1409 #else
1410 static inline void update_idle_core(struct rq *rq) { }
1411 #endif
1412 
1413 #ifdef CONFIG_FAIR_GROUP_SCHED
1414 static inline struct task_struct *task_of(struct sched_entity *se)
1415 {
1416 	SCHED_WARN_ON(!entity_is_task(se));
1417 	return container_of(se, struct task_struct, se);
1418 }
1419 
1420 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1421 {
1422 	return p->se.cfs_rq;
1423 }
1424 
1425 /* runqueue on which this entity is (to be) queued */
1426 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1427 {
1428 	return se->cfs_rq;
1429 }
1430 
1431 /* runqueue "owned" by this group */
1432 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1433 {
1434 	return grp->my_q;
1435 }
1436 
1437 #else
1438 
1439 #define task_of(_se)	container_of(_se, struct task_struct, se)
1440 
1441 static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p)
1442 {
1443 	return &task_rq(p)->cfs;
1444 }
1445 
1446 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1447 {
1448 	const struct task_struct *p = task_of(se);
1449 	struct rq *rq = task_rq(p);
1450 
1451 	return &rq->cfs;
1452 }
1453 
1454 /* runqueue "owned" by this group */
1455 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1456 {
1457 	return NULL;
1458 }
1459 #endif
1460 
1461 extern void update_rq_clock(struct rq *rq);
1462 
1463 /*
1464  * rq::clock_update_flags bits
1465  *
1466  * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1467  *  call to __schedule(). This is an optimisation to avoid
1468  *  neighbouring rq clock updates.
1469  *
1470  * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1471  *  in effect and calls to update_rq_clock() are being ignored.
1472  *
1473  * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1474  *  made to update_rq_clock() since the last time rq::lock was pinned.
1475  *
1476  * If inside of __schedule(), clock_update_flags will have been
1477  * shifted left (a left shift is a cheap operation for the fast path
1478  * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1479  *
1480  *	if (rq-clock_update_flags >= RQCF_UPDATED)
1481  *
1482  * to check if %RQCF_UPDATED is set. It'll never be shifted more than
1483  * one position though, because the next rq_unpin_lock() will shift it
1484  * back.
1485  */
1486 #define RQCF_REQ_SKIP		0x01
1487 #define RQCF_ACT_SKIP		0x02
1488 #define RQCF_UPDATED		0x04
1489 
1490 static inline void assert_clock_updated(struct rq *rq)
1491 {
1492 	/*
1493 	 * The only reason for not seeing a clock update since the
1494 	 * last rq_pin_lock() is if we're currently skipping updates.
1495 	 */
1496 	SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
1497 }
1498 
1499 static inline u64 rq_clock(struct rq *rq)
1500 {
1501 	lockdep_assert_rq_held(rq);
1502 	assert_clock_updated(rq);
1503 
1504 	return rq->clock;
1505 }
1506 
1507 static inline u64 rq_clock_task(struct rq *rq)
1508 {
1509 	lockdep_assert_rq_held(rq);
1510 	assert_clock_updated(rq);
1511 
1512 	return rq->clock_task;
1513 }
1514 
1515 /**
1516  * By default the decay is the default pelt decay period.
1517  * The decay shift can change the decay period in
1518  * multiples of 32.
1519  *  Decay shift		Decay period(ms)
1520  *	0			32
1521  *	1			64
1522  *	2			128
1523  *	3			256
1524  *	4			512
1525  */
1526 extern int sched_thermal_decay_shift;
1527 
1528 static inline u64 rq_clock_thermal(struct rq *rq)
1529 {
1530 	return rq_clock_task(rq) >> sched_thermal_decay_shift;
1531 }
1532 
1533 static inline void rq_clock_skip_update(struct rq *rq)
1534 {
1535 	lockdep_assert_rq_held(rq);
1536 	rq->clock_update_flags |= RQCF_REQ_SKIP;
1537 }
1538 
1539 /*
1540  * See rt task throttling, which is the only time a skip
1541  * request is canceled.
1542  */
1543 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1544 {
1545 	lockdep_assert_rq_held(rq);
1546 	rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1547 }
1548 
1549 struct rq_flags {
1550 	unsigned long flags;
1551 	struct pin_cookie cookie;
1552 #ifdef CONFIG_SCHED_DEBUG
1553 	/*
1554 	 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1555 	 * current pin context is stashed here in case it needs to be
1556 	 * restored in rq_repin_lock().
1557 	 */
1558 	unsigned int clock_update_flags;
1559 #endif
1560 };
1561 
1562 extern struct balance_callback balance_push_callback;
1563 
1564 /*
1565  * Lockdep annotation that avoids accidental unlocks; it's like a
1566  * sticky/continuous lockdep_assert_held().
1567  *
1568  * This avoids code that has access to 'struct rq *rq' (basically everything in
1569  * the scheduler) from accidentally unlocking the rq if they do not also have a
1570  * copy of the (on-stack) 'struct rq_flags rf'.
1571  *
1572  * Also see Documentation/locking/lockdep-design.rst.
1573  */
1574 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1575 {
1576 	rf->cookie = lockdep_pin_lock(__rq_lockp(rq));
1577 
1578 #ifdef CONFIG_SCHED_DEBUG
1579 	rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1580 	rf->clock_update_flags = 0;
1581 #ifdef CONFIG_SMP
1582 	SCHED_WARN_ON(rq->balance_callback && rq->balance_callback != &balance_push_callback);
1583 #endif
1584 #endif
1585 }
1586 
1587 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1588 {
1589 #ifdef CONFIG_SCHED_DEBUG
1590 	if (rq->clock_update_flags > RQCF_ACT_SKIP)
1591 		rf->clock_update_flags = RQCF_UPDATED;
1592 #endif
1593 
1594 	lockdep_unpin_lock(__rq_lockp(rq), rf->cookie);
1595 }
1596 
1597 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1598 {
1599 	lockdep_repin_lock(__rq_lockp(rq), rf->cookie);
1600 
1601 #ifdef CONFIG_SCHED_DEBUG
1602 	/*
1603 	 * Restore the value we stashed in @rf for this pin context.
1604 	 */
1605 	rq->clock_update_flags |= rf->clock_update_flags;
1606 #endif
1607 }
1608 
1609 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1610 	__acquires(rq->lock);
1611 
1612 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1613 	__acquires(p->pi_lock)
1614 	__acquires(rq->lock);
1615 
1616 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1617 	__releases(rq->lock)
1618 {
1619 	rq_unpin_lock(rq, rf);
1620 	raw_spin_rq_unlock(rq);
1621 }
1622 
1623 static inline void
1624 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1625 	__releases(rq->lock)
1626 	__releases(p->pi_lock)
1627 {
1628 	rq_unpin_lock(rq, rf);
1629 	raw_spin_rq_unlock(rq);
1630 	raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1631 }
1632 
1633 static inline void
1634 rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1635 	__acquires(rq->lock)
1636 {
1637 	raw_spin_rq_lock_irqsave(rq, rf->flags);
1638 	rq_pin_lock(rq, rf);
1639 }
1640 
1641 static inline void
1642 rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1643 	__acquires(rq->lock)
1644 {
1645 	raw_spin_rq_lock_irq(rq);
1646 	rq_pin_lock(rq, rf);
1647 }
1648 
1649 static inline void
1650 rq_lock(struct rq *rq, struct rq_flags *rf)
1651 	__acquires(rq->lock)
1652 {
1653 	raw_spin_rq_lock(rq);
1654 	rq_pin_lock(rq, rf);
1655 }
1656 
1657 static inline void
1658 rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1659 	__releases(rq->lock)
1660 {
1661 	rq_unpin_lock(rq, rf);
1662 	raw_spin_rq_unlock_irqrestore(rq, rf->flags);
1663 }
1664 
1665 static inline void
1666 rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1667 	__releases(rq->lock)
1668 {
1669 	rq_unpin_lock(rq, rf);
1670 	raw_spin_rq_unlock_irq(rq);
1671 }
1672 
1673 static inline void
1674 rq_unlock(struct rq *rq, struct rq_flags *rf)
1675 	__releases(rq->lock)
1676 {
1677 	rq_unpin_lock(rq, rf);
1678 	raw_spin_rq_unlock(rq);
1679 }
1680 
1681 static inline struct rq *
1682 this_rq_lock_irq(struct rq_flags *rf)
1683 	__acquires(rq->lock)
1684 {
1685 	struct rq *rq;
1686 
1687 	local_irq_disable();
1688 	rq = this_rq();
1689 	rq_lock(rq, rf);
1690 	return rq;
1691 }
1692 
1693 #ifdef CONFIG_NUMA
1694 enum numa_topology_type {
1695 	NUMA_DIRECT,
1696 	NUMA_GLUELESS_MESH,
1697 	NUMA_BACKPLANE,
1698 };
1699 extern enum numa_topology_type sched_numa_topology_type;
1700 extern int sched_max_numa_distance;
1701 extern bool find_numa_distance(int distance);
1702 extern void sched_init_numa(int offline_node);
1703 extern void sched_update_numa(int cpu, bool online);
1704 extern void sched_domains_numa_masks_set(unsigned int cpu);
1705 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1706 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1707 #else
1708 static inline void sched_init_numa(int offline_node) { }
1709 static inline void sched_update_numa(int cpu, bool online) { }
1710 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
1711 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1712 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1713 {
1714 	return nr_cpu_ids;
1715 }
1716 #endif
1717 
1718 #ifdef CONFIG_NUMA_BALANCING
1719 /* The regions in numa_faults array from task_struct */
1720 enum numa_faults_stats {
1721 	NUMA_MEM = 0,
1722 	NUMA_CPU,
1723 	NUMA_MEMBUF,
1724 	NUMA_CPUBUF
1725 };
1726 extern void sched_setnuma(struct task_struct *p, int node);
1727 extern int migrate_task_to(struct task_struct *p, int cpu);
1728 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1729 			int cpu, int scpu);
1730 extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1731 #else
1732 static inline void
1733 init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1734 {
1735 }
1736 #endif /* CONFIG_NUMA_BALANCING */
1737 
1738 #ifdef CONFIG_SMP
1739 
1740 static inline void
1741 queue_balance_callback(struct rq *rq,
1742 		       struct balance_callback *head,
1743 		       void (*func)(struct rq *rq))
1744 {
1745 	lockdep_assert_rq_held(rq);
1746 
1747 	/*
1748 	 * Don't (re)queue an already queued item; nor queue anything when
1749 	 * balance_push() is active, see the comment with
1750 	 * balance_push_callback.
1751 	 */
1752 	if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
1753 		return;
1754 
1755 	head->func = func;
1756 	head->next = rq->balance_callback;
1757 	rq->balance_callback = head;
1758 }
1759 
1760 #define rcu_dereference_check_sched_domain(p) \
1761 	rcu_dereference_check((p), \
1762 			      lockdep_is_held(&sched_domains_mutex))
1763 
1764 /*
1765  * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1766  * See destroy_sched_domains: call_rcu for details.
1767  *
1768  * The domain tree of any CPU may only be accessed from within
1769  * preempt-disabled sections.
1770  */
1771 #define for_each_domain(cpu, __sd) \
1772 	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1773 			__sd; __sd = __sd->parent)
1774 
1775 /**
1776  * highest_flag_domain - Return highest sched_domain containing flag.
1777  * @cpu:	The CPU whose highest level of sched domain is to
1778  *		be returned.
1779  * @flag:	The flag to check for the highest sched_domain
1780  *		for the given CPU.
1781  *
1782  * Returns the highest sched_domain of a CPU which contains the given flag.
1783  */
1784 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1785 {
1786 	struct sched_domain *sd, *hsd = NULL;
1787 
1788 	for_each_domain(cpu, sd) {
1789 		if (!(sd->flags & flag))
1790 			break;
1791 		hsd = sd;
1792 	}
1793 
1794 	return hsd;
1795 }
1796 
1797 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1798 {
1799 	struct sched_domain *sd;
1800 
1801 	for_each_domain(cpu, sd) {
1802 		if (sd->flags & flag)
1803 			break;
1804 	}
1805 
1806 	return sd;
1807 }
1808 
1809 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
1810 DECLARE_PER_CPU(int, sd_llc_size);
1811 DECLARE_PER_CPU(int, sd_llc_id);
1812 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
1813 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
1814 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
1815 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
1816 extern struct static_key_false sched_asym_cpucapacity;
1817 
1818 static __always_inline bool sched_asym_cpucap_active(void)
1819 {
1820 	return static_branch_unlikely(&sched_asym_cpucapacity);
1821 }
1822 
1823 struct sched_group_capacity {
1824 	atomic_t		ref;
1825 	/*
1826 	 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
1827 	 * for a single CPU.
1828 	 */
1829 	unsigned long		capacity;
1830 	unsigned long		min_capacity;		/* Min per-CPU capacity in group */
1831 	unsigned long		max_capacity;		/* Max per-CPU capacity in group */
1832 	unsigned long		next_update;
1833 	int			imbalance;		/* XXX unrelated to capacity but shared group state */
1834 
1835 #ifdef CONFIG_SCHED_DEBUG
1836 	int			id;
1837 #endif
1838 
1839 	unsigned long		cpumask[];		/* Balance mask */
1840 };
1841 
1842 struct sched_group {
1843 	struct sched_group	*next;			/* Must be a circular list */
1844 	atomic_t		ref;
1845 
1846 	unsigned int		group_weight;
1847 	struct sched_group_capacity *sgc;
1848 	int			asym_prefer_cpu;	/* CPU of highest priority in group */
1849 	int			flags;
1850 
1851 	/*
1852 	 * The CPUs this group covers.
1853 	 *
1854 	 * NOTE: this field is variable length. (Allocated dynamically
1855 	 * by attaching extra space to the end of the structure,
1856 	 * depending on how many CPUs the kernel has booted up with)
1857 	 */
1858 	unsigned long		cpumask[];
1859 };
1860 
1861 static inline struct cpumask *sched_group_span(struct sched_group *sg)
1862 {
1863 	return to_cpumask(sg->cpumask);
1864 }
1865 
1866 /*
1867  * See build_balance_mask().
1868  */
1869 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
1870 {
1871 	return to_cpumask(sg->sgc->cpumask);
1872 }
1873 
1874 extern int group_balance_cpu(struct sched_group *sg);
1875 
1876 #ifdef CONFIG_SCHED_DEBUG
1877 void update_sched_domain_debugfs(void);
1878 void dirty_sched_domain_sysctl(int cpu);
1879 #else
1880 static inline void update_sched_domain_debugfs(void)
1881 {
1882 }
1883 static inline void dirty_sched_domain_sysctl(int cpu)
1884 {
1885 }
1886 #endif
1887 
1888 extern int sched_update_scaling(void);
1889 
1890 static inline const struct cpumask *task_user_cpus(struct task_struct *p)
1891 {
1892 	if (!p->user_cpus_ptr)
1893 		return cpu_possible_mask; /* &init_task.cpus_mask */
1894 	return p->user_cpus_ptr;
1895 }
1896 #endif /* CONFIG_SMP */
1897 
1898 #include "stats.h"
1899 
1900 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS)
1901 
1902 extern void __sched_core_account_forceidle(struct rq *rq);
1903 
1904 static inline void sched_core_account_forceidle(struct rq *rq)
1905 {
1906 	if (schedstat_enabled())
1907 		__sched_core_account_forceidle(rq);
1908 }
1909 
1910 extern void __sched_core_tick(struct rq *rq);
1911 
1912 static inline void sched_core_tick(struct rq *rq)
1913 {
1914 	if (sched_core_enabled(rq) && schedstat_enabled())
1915 		__sched_core_tick(rq);
1916 }
1917 
1918 #else
1919 
1920 static inline void sched_core_account_forceidle(struct rq *rq) {}
1921 
1922 static inline void sched_core_tick(struct rq *rq) {}
1923 
1924 #endif /* CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS */
1925 
1926 #ifdef CONFIG_CGROUP_SCHED
1927 
1928 /*
1929  * Return the group to which this tasks belongs.
1930  *
1931  * We cannot use task_css() and friends because the cgroup subsystem
1932  * changes that value before the cgroup_subsys::attach() method is called,
1933  * therefore we cannot pin it and might observe the wrong value.
1934  *
1935  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
1936  * core changes this before calling sched_move_task().
1937  *
1938  * Instead we use a 'copy' which is updated from sched_move_task() while
1939  * holding both task_struct::pi_lock and rq::lock.
1940  */
1941 static inline struct task_group *task_group(struct task_struct *p)
1942 {
1943 	return p->sched_task_group;
1944 }
1945 
1946 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
1947 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
1948 {
1949 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
1950 	struct task_group *tg = task_group(p);
1951 #endif
1952 
1953 #ifdef CONFIG_FAIR_GROUP_SCHED
1954 	set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
1955 	p->se.cfs_rq = tg->cfs_rq[cpu];
1956 	p->se.parent = tg->se[cpu];
1957 	p->se.depth = tg->se[cpu] ? tg->se[cpu]->depth + 1 : 0;
1958 #endif
1959 
1960 #ifdef CONFIG_RT_GROUP_SCHED
1961 	p->rt.rt_rq  = tg->rt_rq[cpu];
1962 	p->rt.parent = tg->rt_se[cpu];
1963 #endif
1964 }
1965 
1966 #else /* CONFIG_CGROUP_SCHED */
1967 
1968 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
1969 static inline struct task_group *task_group(struct task_struct *p)
1970 {
1971 	return NULL;
1972 }
1973 
1974 #endif /* CONFIG_CGROUP_SCHED */
1975 
1976 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
1977 {
1978 	set_task_rq(p, cpu);
1979 #ifdef CONFIG_SMP
1980 	/*
1981 	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
1982 	 * successfully executed on another CPU. We must ensure that updates of
1983 	 * per-task data have been completed by this moment.
1984 	 */
1985 	smp_wmb();
1986 	WRITE_ONCE(task_thread_info(p)->cpu, cpu);
1987 	p->wake_cpu = cpu;
1988 #endif
1989 }
1990 
1991 /*
1992  * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
1993  */
1994 #ifdef CONFIG_SCHED_DEBUG
1995 # define const_debug __read_mostly
1996 #else
1997 # define const_debug const
1998 #endif
1999 
2000 #define SCHED_FEAT(name, enabled)	\
2001 	__SCHED_FEAT_##name ,
2002 
2003 enum {
2004 #include "features.h"
2005 	__SCHED_FEAT_NR,
2006 };
2007 
2008 #undef SCHED_FEAT
2009 
2010 #ifdef CONFIG_SCHED_DEBUG
2011 
2012 /*
2013  * To support run-time toggling of sched features, all the translation units
2014  * (but core.c) reference the sysctl_sched_features defined in core.c.
2015  */
2016 extern const_debug unsigned int sysctl_sched_features;
2017 
2018 #ifdef CONFIG_JUMP_LABEL
2019 #define SCHED_FEAT(name, enabled)					\
2020 static __always_inline bool static_branch_##name(struct static_key *key) \
2021 {									\
2022 	return static_key_##enabled(key);				\
2023 }
2024 
2025 #include "features.h"
2026 #undef SCHED_FEAT
2027 
2028 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
2029 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
2030 
2031 #else /* !CONFIG_JUMP_LABEL */
2032 
2033 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2034 
2035 #endif /* CONFIG_JUMP_LABEL */
2036 
2037 #else /* !SCHED_DEBUG */
2038 
2039 /*
2040  * Each translation unit has its own copy of sysctl_sched_features to allow
2041  * constants propagation at compile time and compiler optimization based on
2042  * features default.
2043  */
2044 #define SCHED_FEAT(name, enabled)	\
2045 	(1UL << __SCHED_FEAT_##name) * enabled |
2046 static const_debug __maybe_unused unsigned int sysctl_sched_features =
2047 #include "features.h"
2048 	0;
2049 #undef SCHED_FEAT
2050 
2051 #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2052 
2053 #endif /* SCHED_DEBUG */
2054 
2055 extern struct static_key_false sched_numa_balancing;
2056 extern struct static_key_false sched_schedstats;
2057 
2058 static inline u64 global_rt_period(void)
2059 {
2060 	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
2061 }
2062 
2063 static inline u64 global_rt_runtime(void)
2064 {
2065 	if (sysctl_sched_rt_runtime < 0)
2066 		return RUNTIME_INF;
2067 
2068 	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
2069 }
2070 
2071 static inline int task_current(struct rq *rq, struct task_struct *p)
2072 {
2073 	return rq->curr == p;
2074 }
2075 
2076 static inline int task_on_cpu(struct rq *rq, struct task_struct *p)
2077 {
2078 #ifdef CONFIG_SMP
2079 	return p->on_cpu;
2080 #else
2081 	return task_current(rq, p);
2082 #endif
2083 }
2084 
2085 static inline int task_on_rq_queued(struct task_struct *p)
2086 {
2087 	return p->on_rq == TASK_ON_RQ_QUEUED;
2088 }
2089 
2090 static inline int task_on_rq_migrating(struct task_struct *p)
2091 {
2092 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
2093 }
2094 
2095 /* Wake flags. The first three directly map to some SD flag value */
2096 #define WF_EXEC     0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
2097 #define WF_FORK     0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
2098 #define WF_TTWU     0x08 /* Wakeup;            maps to SD_BALANCE_WAKE */
2099 
2100 #define WF_SYNC     0x10 /* Waker goes to sleep after wakeup */
2101 #define WF_MIGRATED 0x20 /* Internal use, task got migrated */
2102 
2103 #ifdef CONFIG_SMP
2104 static_assert(WF_EXEC == SD_BALANCE_EXEC);
2105 static_assert(WF_FORK == SD_BALANCE_FORK);
2106 static_assert(WF_TTWU == SD_BALANCE_WAKE);
2107 #endif
2108 
2109 /*
2110  * To aid in avoiding the subversion of "niceness" due to uneven distribution
2111  * of tasks with abnormal "nice" values across CPUs the contribution that
2112  * each task makes to its run queue's load is weighted according to its
2113  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
2114  * scaled version of the new time slice allocation that they receive on time
2115  * slice expiry etc.
2116  */
2117 
2118 #define WEIGHT_IDLEPRIO		3
2119 #define WMULT_IDLEPRIO		1431655765
2120 
2121 extern const int		sched_prio_to_weight[40];
2122 extern const u32		sched_prio_to_wmult[40];
2123 
2124 /*
2125  * {de,en}queue flags:
2126  *
2127  * DEQUEUE_SLEEP  - task is no longer runnable
2128  * ENQUEUE_WAKEUP - task just became runnable
2129  *
2130  * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
2131  *                are in a known state which allows modification. Such pairs
2132  *                should preserve as much state as possible.
2133  *
2134  * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
2135  *        in the runqueue.
2136  *
2137  * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
2138  * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
2139  * ENQUEUE_MIGRATED  - the task was migrated during wakeup
2140  *
2141  */
2142 
2143 #define DEQUEUE_SLEEP		0x01
2144 #define DEQUEUE_SAVE		0x02 /* Matches ENQUEUE_RESTORE */
2145 #define DEQUEUE_MOVE		0x04 /* Matches ENQUEUE_MOVE */
2146 #define DEQUEUE_NOCLOCK		0x08 /* Matches ENQUEUE_NOCLOCK */
2147 
2148 #define ENQUEUE_WAKEUP		0x01
2149 #define ENQUEUE_RESTORE		0x02
2150 #define ENQUEUE_MOVE		0x04
2151 #define ENQUEUE_NOCLOCK		0x08
2152 
2153 #define ENQUEUE_HEAD		0x10
2154 #define ENQUEUE_REPLENISH	0x20
2155 #ifdef CONFIG_SMP
2156 #define ENQUEUE_MIGRATED	0x40
2157 #else
2158 #define ENQUEUE_MIGRATED	0x00
2159 #endif
2160 
2161 #define RETRY_TASK		((void *)-1UL)
2162 
2163 struct affinity_context {
2164 	const struct cpumask *new_mask;
2165 	struct cpumask *user_mask;
2166 	unsigned int flags;
2167 };
2168 
2169 struct sched_class {
2170 
2171 #ifdef CONFIG_UCLAMP_TASK
2172 	int uclamp_enabled;
2173 #endif
2174 
2175 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
2176 	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
2177 	void (*yield_task)   (struct rq *rq);
2178 	bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
2179 
2180 	void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags);
2181 
2182 	struct task_struct *(*pick_next_task)(struct rq *rq);
2183 
2184 	void (*put_prev_task)(struct rq *rq, struct task_struct *p);
2185 	void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
2186 
2187 #ifdef CONFIG_SMP
2188 	int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2189 	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
2190 
2191 	struct task_struct * (*pick_task)(struct rq *rq);
2192 
2193 	void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
2194 
2195 	void (*task_woken)(struct rq *this_rq, struct task_struct *task);
2196 
2197 	void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx);
2198 
2199 	void (*rq_online)(struct rq *rq);
2200 	void (*rq_offline)(struct rq *rq);
2201 
2202 	struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
2203 #endif
2204 
2205 	void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
2206 	void (*task_fork)(struct task_struct *p);
2207 	void (*task_dead)(struct task_struct *p);
2208 
2209 	/*
2210 	 * The switched_from() call is allowed to drop rq->lock, therefore we
2211 	 * cannot assume the switched_from/switched_to pair is serialized by
2212 	 * rq->lock. They are however serialized by p->pi_lock.
2213 	 */
2214 	void (*switched_from)(struct rq *this_rq, struct task_struct *task);
2215 	void (*switched_to)  (struct rq *this_rq, struct task_struct *task);
2216 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
2217 			      int oldprio);
2218 
2219 	unsigned int (*get_rr_interval)(struct rq *rq,
2220 					struct task_struct *task);
2221 
2222 	void (*update_curr)(struct rq *rq);
2223 
2224 #ifdef CONFIG_FAIR_GROUP_SCHED
2225 	void (*task_change_group)(struct task_struct *p);
2226 #endif
2227 
2228 #ifdef CONFIG_SCHED_CORE
2229 	int (*task_is_throttled)(struct task_struct *p, int cpu);
2230 #endif
2231 };
2232 
2233 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
2234 {
2235 	WARN_ON_ONCE(rq->curr != prev);
2236 	prev->sched_class->put_prev_task(rq, prev);
2237 }
2238 
2239 static inline void set_next_task(struct rq *rq, struct task_struct *next)
2240 {
2241 	next->sched_class->set_next_task(rq, next, false);
2242 }
2243 
2244 
2245 /*
2246  * Helper to define a sched_class instance; each one is placed in a separate
2247  * section which is ordered by the linker script:
2248  *
2249  *   include/asm-generic/vmlinux.lds.h
2250  *
2251  * *CAREFUL* they are laid out in *REVERSE* order!!!
2252  *
2253  * Also enforce alignment on the instance, not the type, to guarantee layout.
2254  */
2255 #define DEFINE_SCHED_CLASS(name) \
2256 const struct sched_class name##_sched_class \
2257 	__aligned(__alignof__(struct sched_class)) \
2258 	__section("__" #name "_sched_class")
2259 
2260 /* Defined in include/asm-generic/vmlinux.lds.h */
2261 extern struct sched_class __sched_class_highest[];
2262 extern struct sched_class __sched_class_lowest[];
2263 
2264 #define for_class_range(class, _from, _to) \
2265 	for (class = (_from); class < (_to); class++)
2266 
2267 #define for_each_class(class) \
2268 	for_class_range(class, __sched_class_highest, __sched_class_lowest)
2269 
2270 #define sched_class_above(_a, _b)	((_a) < (_b))
2271 
2272 extern const struct sched_class stop_sched_class;
2273 extern const struct sched_class dl_sched_class;
2274 extern const struct sched_class rt_sched_class;
2275 extern const struct sched_class fair_sched_class;
2276 extern const struct sched_class idle_sched_class;
2277 
2278 static inline bool sched_stop_runnable(struct rq *rq)
2279 {
2280 	return rq->stop && task_on_rq_queued(rq->stop);
2281 }
2282 
2283 static inline bool sched_dl_runnable(struct rq *rq)
2284 {
2285 	return rq->dl.dl_nr_running > 0;
2286 }
2287 
2288 static inline bool sched_rt_runnable(struct rq *rq)
2289 {
2290 	return rq->rt.rt_queued > 0;
2291 }
2292 
2293 static inline bool sched_fair_runnable(struct rq *rq)
2294 {
2295 	return rq->cfs.nr_running > 0;
2296 }
2297 
2298 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2299 extern struct task_struct *pick_next_task_idle(struct rq *rq);
2300 
2301 #define SCA_CHECK		0x01
2302 #define SCA_MIGRATE_DISABLE	0x02
2303 #define SCA_MIGRATE_ENABLE	0x04
2304 #define SCA_USER		0x08
2305 
2306 #ifdef CONFIG_SMP
2307 
2308 extern void update_group_capacity(struct sched_domain *sd, int cpu);
2309 
2310 extern void trigger_load_balance(struct rq *rq);
2311 
2312 extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx);
2313 
2314 static inline struct task_struct *get_push_task(struct rq *rq)
2315 {
2316 	struct task_struct *p = rq->curr;
2317 
2318 	lockdep_assert_rq_held(rq);
2319 
2320 	if (rq->push_busy)
2321 		return NULL;
2322 
2323 	if (p->nr_cpus_allowed == 1)
2324 		return NULL;
2325 
2326 	if (p->migration_disabled)
2327 		return NULL;
2328 
2329 	rq->push_busy = true;
2330 	return get_task_struct(p);
2331 }
2332 
2333 extern int push_cpu_stop(void *arg);
2334 
2335 #endif
2336 
2337 #ifdef CONFIG_CPU_IDLE
2338 static inline void idle_set_state(struct rq *rq,
2339 				  struct cpuidle_state *idle_state)
2340 {
2341 	rq->idle_state = idle_state;
2342 }
2343 
2344 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2345 {
2346 	SCHED_WARN_ON(!rcu_read_lock_held());
2347 
2348 	return rq->idle_state;
2349 }
2350 #else
2351 static inline void idle_set_state(struct rq *rq,
2352 				  struct cpuidle_state *idle_state)
2353 {
2354 }
2355 
2356 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2357 {
2358 	return NULL;
2359 }
2360 #endif
2361 
2362 extern void schedule_idle(void);
2363 
2364 extern void sysrq_sched_debug_show(void);
2365 extern void sched_init_granularity(void);
2366 extern void update_max_interval(void);
2367 
2368 extern void init_sched_dl_class(void);
2369 extern void init_sched_rt_class(void);
2370 extern void init_sched_fair_class(void);
2371 
2372 extern void reweight_task(struct task_struct *p, int prio);
2373 
2374 extern void resched_curr(struct rq *rq);
2375 extern void resched_cpu(int cpu);
2376 
2377 extern struct rt_bandwidth def_rt_bandwidth;
2378 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
2379 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq);
2380 
2381 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
2382 extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
2383 extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se);
2384 
2385 #define BW_SHIFT		20
2386 #define BW_UNIT			(1 << BW_SHIFT)
2387 #define RATIO_SHIFT		8
2388 #define MAX_BW_BITS		(64 - BW_SHIFT)
2389 #define MAX_BW			((1ULL << MAX_BW_BITS) - 1)
2390 unsigned long to_ratio(u64 period, u64 runtime);
2391 
2392 extern void init_entity_runnable_average(struct sched_entity *se);
2393 extern void post_init_entity_util_avg(struct task_struct *p);
2394 
2395 #ifdef CONFIG_NO_HZ_FULL
2396 extern bool sched_can_stop_tick(struct rq *rq);
2397 extern int __init sched_tick_offload_init(void);
2398 
2399 /*
2400  * Tick may be needed by tasks in the runqueue depending on their policy and
2401  * requirements. If tick is needed, lets send the target an IPI to kick it out of
2402  * nohz mode if necessary.
2403  */
2404 static inline void sched_update_tick_dependency(struct rq *rq)
2405 {
2406 	int cpu = cpu_of(rq);
2407 
2408 	if (!tick_nohz_full_cpu(cpu))
2409 		return;
2410 
2411 	if (sched_can_stop_tick(rq))
2412 		tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
2413 	else
2414 		tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
2415 }
2416 #else
2417 static inline int sched_tick_offload_init(void) { return 0; }
2418 static inline void sched_update_tick_dependency(struct rq *rq) { }
2419 #endif
2420 
2421 static inline void add_nr_running(struct rq *rq, unsigned count)
2422 {
2423 	unsigned prev_nr = rq->nr_running;
2424 
2425 	rq->nr_running = prev_nr + count;
2426 	if (trace_sched_update_nr_running_tp_enabled()) {
2427 		call_trace_sched_update_nr_running(rq, count);
2428 	}
2429 
2430 #ifdef CONFIG_SMP
2431 	if (prev_nr < 2 && rq->nr_running >= 2) {
2432 		if (!READ_ONCE(rq->rd->overload))
2433 			WRITE_ONCE(rq->rd->overload, 1);
2434 	}
2435 #endif
2436 
2437 	sched_update_tick_dependency(rq);
2438 }
2439 
2440 static inline void sub_nr_running(struct rq *rq, unsigned count)
2441 {
2442 	rq->nr_running -= count;
2443 	if (trace_sched_update_nr_running_tp_enabled()) {
2444 		call_trace_sched_update_nr_running(rq, -count);
2445 	}
2446 
2447 	/* Check if we still need preemption */
2448 	sched_update_tick_dependency(rq);
2449 }
2450 
2451 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
2452 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
2453 
2454 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
2455 
2456 #ifdef CONFIG_PREEMPT_RT
2457 #define SCHED_NR_MIGRATE_BREAK 8
2458 #else
2459 #define SCHED_NR_MIGRATE_BREAK 32
2460 #endif
2461 
2462 extern const_debug unsigned int sysctl_sched_nr_migrate;
2463 extern const_debug unsigned int sysctl_sched_migration_cost;
2464 
2465 #ifdef CONFIG_SCHED_DEBUG
2466 extern unsigned int sysctl_sched_latency;
2467 extern unsigned int sysctl_sched_min_granularity;
2468 extern unsigned int sysctl_sched_idle_min_granularity;
2469 extern unsigned int sysctl_sched_wakeup_granularity;
2470 extern int sysctl_resched_latency_warn_ms;
2471 extern int sysctl_resched_latency_warn_once;
2472 
2473 extern unsigned int sysctl_sched_tunable_scaling;
2474 
2475 extern unsigned int sysctl_numa_balancing_scan_delay;
2476 extern unsigned int sysctl_numa_balancing_scan_period_min;
2477 extern unsigned int sysctl_numa_balancing_scan_period_max;
2478 extern unsigned int sysctl_numa_balancing_scan_size;
2479 extern unsigned int sysctl_numa_balancing_hot_threshold;
2480 #endif
2481 
2482 #ifdef CONFIG_SCHED_HRTICK
2483 
2484 /*
2485  * Use hrtick when:
2486  *  - enabled by features
2487  *  - hrtimer is actually high res
2488  */
2489 static inline int hrtick_enabled(struct rq *rq)
2490 {
2491 	if (!cpu_active(cpu_of(rq)))
2492 		return 0;
2493 	return hrtimer_is_hres_active(&rq->hrtick_timer);
2494 }
2495 
2496 static inline int hrtick_enabled_fair(struct rq *rq)
2497 {
2498 	if (!sched_feat(HRTICK))
2499 		return 0;
2500 	return hrtick_enabled(rq);
2501 }
2502 
2503 static inline int hrtick_enabled_dl(struct rq *rq)
2504 {
2505 	if (!sched_feat(HRTICK_DL))
2506 		return 0;
2507 	return hrtick_enabled(rq);
2508 }
2509 
2510 void hrtick_start(struct rq *rq, u64 delay);
2511 
2512 #else
2513 
2514 static inline int hrtick_enabled_fair(struct rq *rq)
2515 {
2516 	return 0;
2517 }
2518 
2519 static inline int hrtick_enabled_dl(struct rq *rq)
2520 {
2521 	return 0;
2522 }
2523 
2524 static inline int hrtick_enabled(struct rq *rq)
2525 {
2526 	return 0;
2527 }
2528 
2529 #endif /* CONFIG_SCHED_HRTICK */
2530 
2531 #ifndef arch_scale_freq_tick
2532 static __always_inline
2533 void arch_scale_freq_tick(void)
2534 {
2535 }
2536 #endif
2537 
2538 #ifndef arch_scale_freq_capacity
2539 /**
2540  * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
2541  * @cpu: the CPU in question.
2542  *
2543  * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
2544  *
2545  *     f_curr
2546  *     ------ * SCHED_CAPACITY_SCALE
2547  *     f_max
2548  */
2549 static __always_inline
2550 unsigned long arch_scale_freq_capacity(int cpu)
2551 {
2552 	return SCHED_CAPACITY_SCALE;
2553 }
2554 #endif
2555 
2556 #ifdef CONFIG_SCHED_DEBUG
2557 /*
2558  * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to
2559  * acquire rq lock instead of rq_lock(). So at the end of these two functions
2560  * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of
2561  * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning.
2562  */
2563 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2)
2564 {
2565 	rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
2566 	/* rq1 == rq2 for !CONFIG_SMP, so just clear RQCF_UPDATED once. */
2567 #ifdef CONFIG_SMP
2568 	rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
2569 #endif
2570 }
2571 #else
2572 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2) {}
2573 #endif
2574 
2575 #ifdef CONFIG_SMP
2576 
2577 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2)
2578 {
2579 #ifdef CONFIG_SCHED_CORE
2580 	/*
2581 	 * In order to not have {0,2},{1,3} turn into into an AB-BA,
2582 	 * order by core-id first and cpu-id second.
2583 	 *
2584 	 * Notably:
2585 	 *
2586 	 *	double_rq_lock(0,3); will take core-0, core-1 lock
2587 	 *	double_rq_lock(1,2); will take core-1, core-0 lock
2588 	 *
2589 	 * when only cpu-id is considered.
2590 	 */
2591 	if (rq1->core->cpu < rq2->core->cpu)
2592 		return true;
2593 	if (rq1->core->cpu > rq2->core->cpu)
2594 		return false;
2595 
2596 	/*
2597 	 * __sched_core_flip() relies on SMT having cpu-id lock order.
2598 	 */
2599 #endif
2600 	return rq1->cpu < rq2->cpu;
2601 }
2602 
2603 extern void double_rq_lock(struct rq *rq1, struct rq *rq2);
2604 
2605 #ifdef CONFIG_PREEMPTION
2606 
2607 /*
2608  * fair double_lock_balance: Safely acquires both rq->locks in a fair
2609  * way at the expense of forcing extra atomic operations in all
2610  * invocations.  This assures that the double_lock is acquired using the
2611  * same underlying policy as the spinlock_t on this architecture, which
2612  * reduces latency compared to the unfair variant below.  However, it
2613  * also adds more overhead and therefore may reduce throughput.
2614  */
2615 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2616 	__releases(this_rq->lock)
2617 	__acquires(busiest->lock)
2618 	__acquires(this_rq->lock)
2619 {
2620 	raw_spin_rq_unlock(this_rq);
2621 	double_rq_lock(this_rq, busiest);
2622 
2623 	return 1;
2624 }
2625 
2626 #else
2627 /*
2628  * Unfair double_lock_balance: Optimizes throughput at the expense of
2629  * latency by eliminating extra atomic operations when the locks are
2630  * already in proper order on entry.  This favors lower CPU-ids and will
2631  * grant the double lock to lower CPUs over higher ids under contention,
2632  * regardless of entry order into the function.
2633  */
2634 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2635 	__releases(this_rq->lock)
2636 	__acquires(busiest->lock)
2637 	__acquires(this_rq->lock)
2638 {
2639 	if (__rq_lockp(this_rq) == __rq_lockp(busiest) ||
2640 	    likely(raw_spin_rq_trylock(busiest))) {
2641 		double_rq_clock_clear_update(this_rq, busiest);
2642 		return 0;
2643 	}
2644 
2645 	if (rq_order_less(this_rq, busiest)) {
2646 		raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING);
2647 		double_rq_clock_clear_update(this_rq, busiest);
2648 		return 0;
2649 	}
2650 
2651 	raw_spin_rq_unlock(this_rq);
2652 	double_rq_lock(this_rq, busiest);
2653 
2654 	return 1;
2655 }
2656 
2657 #endif /* CONFIG_PREEMPTION */
2658 
2659 /*
2660  * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
2661  */
2662 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
2663 {
2664 	lockdep_assert_irqs_disabled();
2665 
2666 	return _double_lock_balance(this_rq, busiest);
2667 }
2668 
2669 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
2670 	__releases(busiest->lock)
2671 {
2672 	if (__rq_lockp(this_rq) != __rq_lockp(busiest))
2673 		raw_spin_rq_unlock(busiest);
2674 	lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_);
2675 }
2676 
2677 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
2678 {
2679 	if (l1 > l2)
2680 		swap(l1, l2);
2681 
2682 	spin_lock(l1);
2683 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2684 }
2685 
2686 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
2687 {
2688 	if (l1 > l2)
2689 		swap(l1, l2);
2690 
2691 	spin_lock_irq(l1);
2692 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2693 }
2694 
2695 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
2696 {
2697 	if (l1 > l2)
2698 		swap(l1, l2);
2699 
2700 	raw_spin_lock(l1);
2701 	raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2702 }
2703 
2704 /*
2705  * double_rq_unlock - safely unlock two runqueues
2706  *
2707  * Note this does not restore interrupts like task_rq_unlock,
2708  * you need to do so manually after calling.
2709  */
2710 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2711 	__releases(rq1->lock)
2712 	__releases(rq2->lock)
2713 {
2714 	if (__rq_lockp(rq1) != __rq_lockp(rq2))
2715 		raw_spin_rq_unlock(rq2);
2716 	else
2717 		__release(rq2->lock);
2718 	raw_spin_rq_unlock(rq1);
2719 }
2720 
2721 extern void set_rq_online (struct rq *rq);
2722 extern void set_rq_offline(struct rq *rq);
2723 extern bool sched_smp_initialized;
2724 
2725 #else /* CONFIG_SMP */
2726 
2727 /*
2728  * double_rq_lock - safely lock two runqueues
2729  *
2730  * Note this does not disable interrupts like task_rq_lock,
2731  * you need to do so manually before calling.
2732  */
2733 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2734 	__acquires(rq1->lock)
2735 	__acquires(rq2->lock)
2736 {
2737 	WARN_ON_ONCE(!irqs_disabled());
2738 	WARN_ON_ONCE(rq1 != rq2);
2739 	raw_spin_rq_lock(rq1);
2740 	__acquire(rq2->lock);	/* Fake it out ;) */
2741 	double_rq_clock_clear_update(rq1, rq2);
2742 }
2743 
2744 /*
2745  * double_rq_unlock - safely unlock two runqueues
2746  *
2747  * Note this does not restore interrupts like task_rq_unlock,
2748  * you need to do so manually after calling.
2749  */
2750 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2751 	__releases(rq1->lock)
2752 	__releases(rq2->lock)
2753 {
2754 	WARN_ON_ONCE(rq1 != rq2);
2755 	raw_spin_rq_unlock(rq1);
2756 	__release(rq2->lock);
2757 }
2758 
2759 #endif
2760 
2761 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
2762 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
2763 
2764 #ifdef	CONFIG_SCHED_DEBUG
2765 extern bool sched_debug_verbose;
2766 
2767 extern void print_cfs_stats(struct seq_file *m, int cpu);
2768 extern void print_rt_stats(struct seq_file *m, int cpu);
2769 extern void print_dl_stats(struct seq_file *m, int cpu);
2770 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
2771 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
2772 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
2773 
2774 extern void resched_latency_warn(int cpu, u64 latency);
2775 #ifdef CONFIG_NUMA_BALANCING
2776 extern void
2777 show_numa_stats(struct task_struct *p, struct seq_file *m);
2778 extern void
2779 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
2780 	unsigned long tpf, unsigned long gsf, unsigned long gpf);
2781 #endif /* CONFIG_NUMA_BALANCING */
2782 #else
2783 static inline void resched_latency_warn(int cpu, u64 latency) {}
2784 #endif /* CONFIG_SCHED_DEBUG */
2785 
2786 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
2787 extern void init_rt_rq(struct rt_rq *rt_rq);
2788 extern void init_dl_rq(struct dl_rq *dl_rq);
2789 
2790 extern void cfs_bandwidth_usage_inc(void);
2791 extern void cfs_bandwidth_usage_dec(void);
2792 
2793 #ifdef CONFIG_NO_HZ_COMMON
2794 #define NOHZ_BALANCE_KICK_BIT	0
2795 #define NOHZ_STATS_KICK_BIT	1
2796 #define NOHZ_NEWILB_KICK_BIT	2
2797 #define NOHZ_NEXT_KICK_BIT	3
2798 
2799 /* Run rebalance_domains() */
2800 #define NOHZ_BALANCE_KICK	BIT(NOHZ_BALANCE_KICK_BIT)
2801 /* Update blocked load */
2802 #define NOHZ_STATS_KICK		BIT(NOHZ_STATS_KICK_BIT)
2803 /* Update blocked load when entering idle */
2804 #define NOHZ_NEWILB_KICK	BIT(NOHZ_NEWILB_KICK_BIT)
2805 /* Update nohz.next_balance */
2806 #define NOHZ_NEXT_KICK		BIT(NOHZ_NEXT_KICK_BIT)
2807 
2808 #define NOHZ_KICK_MASK	(NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK)
2809 
2810 #define nohz_flags(cpu)	(&cpu_rq(cpu)->nohz_flags)
2811 
2812 extern void nohz_balance_exit_idle(struct rq *rq);
2813 #else
2814 static inline void nohz_balance_exit_idle(struct rq *rq) { }
2815 #endif
2816 
2817 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
2818 extern void nohz_run_idle_balance(int cpu);
2819 #else
2820 static inline void nohz_run_idle_balance(int cpu) { }
2821 #endif
2822 
2823 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2824 struct irqtime {
2825 	u64			total;
2826 	u64			tick_delta;
2827 	u64			irq_start_time;
2828 	struct u64_stats_sync	sync;
2829 };
2830 
2831 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
2832 
2833 /*
2834  * Returns the irqtime minus the softirq time computed by ksoftirqd.
2835  * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime
2836  * and never move forward.
2837  */
2838 static inline u64 irq_time_read(int cpu)
2839 {
2840 	struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
2841 	unsigned int seq;
2842 	u64 total;
2843 
2844 	do {
2845 		seq = __u64_stats_fetch_begin(&irqtime->sync);
2846 		total = irqtime->total;
2847 	} while (__u64_stats_fetch_retry(&irqtime->sync, seq));
2848 
2849 	return total;
2850 }
2851 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
2852 
2853 #ifdef CONFIG_CPU_FREQ
2854 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
2855 
2856 /**
2857  * cpufreq_update_util - Take a note about CPU utilization changes.
2858  * @rq: Runqueue to carry out the update for.
2859  * @flags: Update reason flags.
2860  *
2861  * This function is called by the scheduler on the CPU whose utilization is
2862  * being updated.
2863  *
2864  * It can only be called from RCU-sched read-side critical sections.
2865  *
2866  * The way cpufreq is currently arranged requires it to evaluate the CPU
2867  * performance state (frequency/voltage) on a regular basis to prevent it from
2868  * being stuck in a completely inadequate performance level for too long.
2869  * That is not guaranteed to happen if the updates are only triggered from CFS
2870  * and DL, though, because they may not be coming in if only RT tasks are
2871  * active all the time (or there are RT tasks only).
2872  *
2873  * As a workaround for that issue, this function is called periodically by the
2874  * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
2875  * but that really is a band-aid.  Going forward it should be replaced with
2876  * solutions targeted more specifically at RT tasks.
2877  */
2878 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
2879 {
2880 	struct update_util_data *data;
2881 
2882 	data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
2883 						  cpu_of(rq)));
2884 	if (data)
2885 		data->func(data, rq_clock(rq), flags);
2886 }
2887 #else
2888 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
2889 #endif /* CONFIG_CPU_FREQ */
2890 
2891 #ifdef arch_scale_freq_capacity
2892 # ifndef arch_scale_freq_invariant
2893 #  define arch_scale_freq_invariant()	true
2894 # endif
2895 #else
2896 # define arch_scale_freq_invariant()	false
2897 #endif
2898 
2899 #ifdef CONFIG_SMP
2900 static inline unsigned long capacity_orig_of(int cpu)
2901 {
2902 	return cpu_rq(cpu)->cpu_capacity_orig;
2903 }
2904 
2905 /**
2906  * enum cpu_util_type - CPU utilization type
2907  * @FREQUENCY_UTIL:	Utilization used to select frequency
2908  * @ENERGY_UTIL:	Utilization used during energy calculation
2909  *
2910  * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time
2911  * need to be aggregated differently depending on the usage made of them. This
2912  * enum is used within effective_cpu_util() to differentiate the types of
2913  * utilization expected by the callers, and adjust the aggregation accordingly.
2914  */
2915 enum cpu_util_type {
2916 	FREQUENCY_UTIL,
2917 	ENERGY_UTIL,
2918 };
2919 
2920 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
2921 				 enum cpu_util_type type,
2922 				 struct task_struct *p);
2923 
2924 /*
2925  * Verify the fitness of task @p to run on @cpu taking into account the
2926  * CPU original capacity and the runtime/deadline ratio of the task.
2927  *
2928  * The function will return true if the original capacity of @cpu is
2929  * greater than or equal to task's deadline density right shifted by
2930  * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise.
2931  */
2932 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
2933 {
2934 	unsigned long cap = arch_scale_cpu_capacity(cpu);
2935 
2936 	return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT);
2937 }
2938 
2939 static inline unsigned long cpu_bw_dl(struct rq *rq)
2940 {
2941 	return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
2942 }
2943 
2944 static inline unsigned long cpu_util_dl(struct rq *rq)
2945 {
2946 	return READ_ONCE(rq->avg_dl.util_avg);
2947 }
2948 
2949 /**
2950  * cpu_util_cfs() - Estimates the amount of CPU capacity used by CFS tasks.
2951  * @cpu: the CPU to get the utilization for.
2952  *
2953  * The unit of the return value must be the same as the one of CPU capacity
2954  * so that CPU utilization can be compared with CPU capacity.
2955  *
2956  * CPU utilization is the sum of running time of runnable tasks plus the
2957  * recent utilization of currently non-runnable tasks on that CPU.
2958  * It represents the amount of CPU capacity currently used by CFS tasks in
2959  * the range [0..max CPU capacity] with max CPU capacity being the CPU
2960  * capacity at f_max.
2961  *
2962  * The estimated CPU utilization is defined as the maximum between CPU
2963  * utilization and sum of the estimated utilization of the currently
2964  * runnable tasks on that CPU. It preserves a utilization "snapshot" of
2965  * previously-executed tasks, which helps better deduce how busy a CPU will
2966  * be when a long-sleeping task wakes up. The contribution to CPU utilization
2967  * of such a task would be significantly decayed at this point of time.
2968  *
2969  * CPU utilization can be higher than the current CPU capacity
2970  * (f_curr/f_max * max CPU capacity) or even the max CPU capacity because
2971  * of rounding errors as well as task migrations or wakeups of new tasks.
2972  * CPU utilization has to be capped to fit into the [0..max CPU capacity]
2973  * range. Otherwise a group of CPUs (CPU0 util = 121% + CPU1 util = 80%)
2974  * could be seen as over-utilized even though CPU1 has 20% of spare CPU
2975  * capacity. CPU utilization is allowed to overshoot current CPU capacity
2976  * though since this is useful for predicting the CPU capacity required
2977  * after task migrations (scheduler-driven DVFS).
2978  *
2979  * Return: (Estimated) utilization for the specified CPU.
2980  */
2981 static inline unsigned long cpu_util_cfs(int cpu)
2982 {
2983 	struct cfs_rq *cfs_rq;
2984 	unsigned long util;
2985 
2986 	cfs_rq = &cpu_rq(cpu)->cfs;
2987 	util = READ_ONCE(cfs_rq->avg.util_avg);
2988 
2989 	if (sched_feat(UTIL_EST)) {
2990 		util = max_t(unsigned long, util,
2991 			     READ_ONCE(cfs_rq->avg.util_est.enqueued));
2992 	}
2993 
2994 	return min(util, capacity_orig_of(cpu));
2995 }
2996 
2997 static inline unsigned long cpu_util_rt(struct rq *rq)
2998 {
2999 	return READ_ONCE(rq->avg_rt.util_avg);
3000 }
3001 #endif
3002 
3003 #ifdef CONFIG_UCLAMP_TASK
3004 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
3005 
3006 static inline unsigned long uclamp_rq_get(struct rq *rq,
3007 					  enum uclamp_id clamp_id)
3008 {
3009 	return READ_ONCE(rq->uclamp[clamp_id].value);
3010 }
3011 
3012 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id,
3013 				 unsigned int value)
3014 {
3015 	WRITE_ONCE(rq->uclamp[clamp_id].value, value);
3016 }
3017 
3018 static inline bool uclamp_rq_is_idle(struct rq *rq)
3019 {
3020 	return rq->uclamp_flags & UCLAMP_FLAG_IDLE;
3021 }
3022 
3023 /**
3024  * uclamp_rq_util_with - clamp @util with @rq and @p effective uclamp values.
3025  * @rq:		The rq to clamp against. Must not be NULL.
3026  * @util:	The util value to clamp.
3027  * @p:		The task to clamp against. Can be NULL if you want to clamp
3028  *		against @rq only.
3029  *
3030  * Clamps the passed @util to the max(@rq, @p) effective uclamp values.
3031  *
3032  * If sched_uclamp_used static key is disabled, then just return the util
3033  * without any clamping since uclamp aggregation at the rq level in the fast
3034  * path is disabled, rendering this operation a NOP.
3035  *
3036  * Use uclamp_eff_value() if you don't care about uclamp values at rq level. It
3037  * will return the correct effective uclamp value of the task even if the
3038  * static key is disabled.
3039  */
3040 static __always_inline
3041 unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
3042 				  struct task_struct *p)
3043 {
3044 	unsigned long min_util = 0;
3045 	unsigned long max_util = 0;
3046 
3047 	if (!static_branch_likely(&sched_uclamp_used))
3048 		return util;
3049 
3050 	if (p) {
3051 		min_util = uclamp_eff_value(p, UCLAMP_MIN);
3052 		max_util = uclamp_eff_value(p, UCLAMP_MAX);
3053 
3054 		/*
3055 		 * Ignore last runnable task's max clamp, as this task will
3056 		 * reset it. Similarly, no need to read the rq's min clamp.
3057 		 */
3058 		if (uclamp_rq_is_idle(rq))
3059 			goto out;
3060 	}
3061 
3062 	min_util = max_t(unsigned long, min_util, uclamp_rq_get(rq, UCLAMP_MIN));
3063 	max_util = max_t(unsigned long, max_util, uclamp_rq_get(rq, UCLAMP_MAX));
3064 out:
3065 	/*
3066 	 * Since CPU's {min,max}_util clamps are MAX aggregated considering
3067 	 * RUNNABLE tasks with _different_ clamps, we can end up with an
3068 	 * inversion. Fix it now when the clamps are applied.
3069 	 */
3070 	if (unlikely(min_util >= max_util))
3071 		return min_util;
3072 
3073 	return clamp(util, min_util, max_util);
3074 }
3075 
3076 /* Is the rq being capped/throttled by uclamp_max? */
3077 static inline bool uclamp_rq_is_capped(struct rq *rq)
3078 {
3079 	unsigned long rq_util;
3080 	unsigned long max_util;
3081 
3082 	if (!static_branch_likely(&sched_uclamp_used))
3083 		return false;
3084 
3085 	rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq);
3086 	max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
3087 
3088 	return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util;
3089 }
3090 
3091 /*
3092  * When uclamp is compiled in, the aggregation at rq level is 'turned off'
3093  * by default in the fast path and only gets turned on once userspace performs
3094  * an operation that requires it.
3095  *
3096  * Returns true if userspace opted-in to use uclamp and aggregation at rq level
3097  * hence is active.
3098  */
3099 static inline bool uclamp_is_used(void)
3100 {
3101 	return static_branch_likely(&sched_uclamp_used);
3102 }
3103 #else /* CONFIG_UCLAMP_TASK */
3104 static inline unsigned long uclamp_eff_value(struct task_struct *p,
3105 					     enum uclamp_id clamp_id)
3106 {
3107 	if (clamp_id == UCLAMP_MIN)
3108 		return 0;
3109 
3110 	return SCHED_CAPACITY_SCALE;
3111 }
3112 
3113 static inline
3114 unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
3115 				  struct task_struct *p)
3116 {
3117 	return util;
3118 }
3119 
3120 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; }
3121 
3122 static inline bool uclamp_is_used(void)
3123 {
3124 	return false;
3125 }
3126 
3127 static inline unsigned long uclamp_rq_get(struct rq *rq,
3128 					  enum uclamp_id clamp_id)
3129 {
3130 	if (clamp_id == UCLAMP_MIN)
3131 		return 0;
3132 
3133 	return SCHED_CAPACITY_SCALE;
3134 }
3135 
3136 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id,
3137 				 unsigned int value)
3138 {
3139 }
3140 
3141 static inline bool uclamp_rq_is_idle(struct rq *rq)
3142 {
3143 	return false;
3144 }
3145 #endif /* CONFIG_UCLAMP_TASK */
3146 
3147 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
3148 static inline unsigned long cpu_util_irq(struct rq *rq)
3149 {
3150 	return rq->avg_irq.util_avg;
3151 }
3152 
3153 static inline
3154 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3155 {
3156 	util *= (max - irq);
3157 	util /= max;
3158 
3159 	return util;
3160 
3161 }
3162 #else
3163 static inline unsigned long cpu_util_irq(struct rq *rq)
3164 {
3165 	return 0;
3166 }
3167 
3168 static inline
3169 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3170 {
3171 	return util;
3172 }
3173 #endif
3174 
3175 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
3176 
3177 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
3178 
3179 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
3180 
3181 static inline bool sched_energy_enabled(void)
3182 {
3183 	return static_branch_unlikely(&sched_energy_present);
3184 }
3185 
3186 #else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
3187 
3188 #define perf_domain_span(pd) NULL
3189 static inline bool sched_energy_enabled(void) { return false; }
3190 
3191 #endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
3192 
3193 #ifdef CONFIG_MEMBARRIER
3194 /*
3195  * The scheduler provides memory barriers required by membarrier between:
3196  * - prior user-space memory accesses and store to rq->membarrier_state,
3197  * - store to rq->membarrier_state and following user-space memory accesses.
3198  * In the same way it provides those guarantees around store to rq->curr.
3199  */
3200 static inline void membarrier_switch_mm(struct rq *rq,
3201 					struct mm_struct *prev_mm,
3202 					struct mm_struct *next_mm)
3203 {
3204 	int membarrier_state;
3205 
3206 	if (prev_mm == next_mm)
3207 		return;
3208 
3209 	membarrier_state = atomic_read(&next_mm->membarrier_state);
3210 	if (READ_ONCE(rq->membarrier_state) == membarrier_state)
3211 		return;
3212 
3213 	WRITE_ONCE(rq->membarrier_state, membarrier_state);
3214 }
3215 #else
3216 static inline void membarrier_switch_mm(struct rq *rq,
3217 					struct mm_struct *prev_mm,
3218 					struct mm_struct *next_mm)
3219 {
3220 }
3221 #endif
3222 
3223 #ifdef CONFIG_SMP
3224 static inline bool is_per_cpu_kthread(struct task_struct *p)
3225 {
3226 	if (!(p->flags & PF_KTHREAD))
3227 		return false;
3228 
3229 	if (p->nr_cpus_allowed != 1)
3230 		return false;
3231 
3232 	return true;
3233 }
3234 #endif
3235 
3236 extern void swake_up_all_locked(struct swait_queue_head *q);
3237 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
3238 
3239 #ifdef CONFIG_PREEMPT_DYNAMIC
3240 extern int preempt_dynamic_mode;
3241 extern int sched_dynamic_mode(const char *str);
3242 extern void sched_dynamic_update(int mode);
3243 #endif
3244 
3245 static inline void update_current_exec_runtime(struct task_struct *curr,
3246 						u64 now, u64 delta_exec)
3247 {
3248 	curr->se.sum_exec_runtime += delta_exec;
3249 	account_group_exec_runtime(curr, delta_exec);
3250 
3251 	curr->se.exec_start = now;
3252 	cgroup_account_cputime(curr, delta_exec);
3253 }
3254 
3255 #ifdef CONFIG_SCHED_MM_CID
3256 
3257 #define SCHED_MM_CID_PERIOD_NS	(100ULL * 1000000)	/* 100ms */
3258 #define MM_CID_SCAN_DELAY	100			/* 100ms */
3259 
3260 extern raw_spinlock_t cid_lock;
3261 extern int use_cid_lock;
3262 
3263 extern void sched_mm_cid_migrate_from(struct task_struct *t);
3264 extern void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t);
3265 extern void task_tick_mm_cid(struct rq *rq, struct task_struct *curr);
3266 extern void init_sched_mm_cid(struct task_struct *t);
3267 
3268 static inline void __mm_cid_put(struct mm_struct *mm, int cid)
3269 {
3270 	if (cid < 0)
3271 		return;
3272 	cpumask_clear_cpu(cid, mm_cidmask(mm));
3273 }
3274 
3275 /*
3276  * The per-mm/cpu cid can have the MM_CID_LAZY_PUT flag set or transition to
3277  * the MM_CID_UNSET state without holding the rq lock, but the rq lock needs to
3278  * be held to transition to other states.
3279  *
3280  * State transitions synchronized with cmpxchg or try_cmpxchg need to be
3281  * consistent across cpus, which prevents use of this_cpu_cmpxchg.
3282  */
3283 static inline void mm_cid_put_lazy(struct task_struct *t)
3284 {
3285 	struct mm_struct *mm = t->mm;
3286 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3287 	int cid;
3288 
3289 	lockdep_assert_irqs_disabled();
3290 	cid = __this_cpu_read(pcpu_cid->cid);
3291 	if (!mm_cid_is_lazy_put(cid) ||
3292 	    !try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET))
3293 		return;
3294 	__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3295 }
3296 
3297 static inline int mm_cid_pcpu_unset(struct mm_struct *mm)
3298 {
3299 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3300 	int cid, res;
3301 
3302 	lockdep_assert_irqs_disabled();
3303 	cid = __this_cpu_read(pcpu_cid->cid);
3304 	for (;;) {
3305 		if (mm_cid_is_unset(cid))
3306 			return MM_CID_UNSET;
3307 		/*
3308 		 * Attempt transition from valid or lazy-put to unset.
3309 		 */
3310 		res = cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, cid, MM_CID_UNSET);
3311 		if (res == cid)
3312 			break;
3313 		cid = res;
3314 	}
3315 	return cid;
3316 }
3317 
3318 static inline void mm_cid_put(struct mm_struct *mm)
3319 {
3320 	int cid;
3321 
3322 	lockdep_assert_irqs_disabled();
3323 	cid = mm_cid_pcpu_unset(mm);
3324 	if (cid == MM_CID_UNSET)
3325 		return;
3326 	__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3327 }
3328 
3329 static inline int __mm_cid_try_get(struct mm_struct *mm)
3330 {
3331 	struct cpumask *cpumask;
3332 	int cid;
3333 
3334 	cpumask = mm_cidmask(mm);
3335 	/*
3336 	 * Retry finding first zero bit if the mask is temporarily
3337 	 * filled. This only happens during concurrent remote-clear
3338 	 * which owns a cid without holding a rq lock.
3339 	 */
3340 	for (;;) {
3341 		cid = cpumask_first_zero(cpumask);
3342 		if (cid < nr_cpu_ids)
3343 			break;
3344 		cpu_relax();
3345 	}
3346 	if (cpumask_test_and_set_cpu(cid, cpumask))
3347 		return -1;
3348 	return cid;
3349 }
3350 
3351 /*
3352  * Save a snapshot of the current runqueue time of this cpu
3353  * with the per-cpu cid value, allowing to estimate how recently it was used.
3354  */
3355 static inline void mm_cid_snapshot_time(struct rq *rq, struct mm_struct *mm)
3356 {
3357 	struct mm_cid *pcpu_cid = per_cpu_ptr(mm->pcpu_cid, cpu_of(rq));
3358 
3359 	lockdep_assert_rq_held(rq);
3360 	WRITE_ONCE(pcpu_cid->time, rq->clock);
3361 }
3362 
3363 static inline int __mm_cid_get(struct rq *rq, struct mm_struct *mm)
3364 {
3365 	int cid;
3366 
3367 	/*
3368 	 * All allocations (even those using the cid_lock) are lock-free. If
3369 	 * use_cid_lock is set, hold the cid_lock to perform cid allocation to
3370 	 * guarantee forward progress.
3371 	 */
3372 	if (!READ_ONCE(use_cid_lock)) {
3373 		cid = __mm_cid_try_get(mm);
3374 		if (cid >= 0)
3375 			goto end;
3376 		raw_spin_lock(&cid_lock);
3377 	} else {
3378 		raw_spin_lock(&cid_lock);
3379 		cid = __mm_cid_try_get(mm);
3380 		if (cid >= 0)
3381 			goto unlock;
3382 	}
3383 
3384 	/*
3385 	 * cid concurrently allocated. Retry while forcing following
3386 	 * allocations to use the cid_lock to ensure forward progress.
3387 	 */
3388 	WRITE_ONCE(use_cid_lock, 1);
3389 	/*
3390 	 * Set use_cid_lock before allocation. Only care about program order
3391 	 * because this is only required for forward progress.
3392 	 */
3393 	barrier();
3394 	/*
3395 	 * Retry until it succeeds. It is guaranteed to eventually succeed once
3396 	 * all newcoming allocations observe the use_cid_lock flag set.
3397 	 */
3398 	do {
3399 		cid = __mm_cid_try_get(mm);
3400 		cpu_relax();
3401 	} while (cid < 0);
3402 	/*
3403 	 * Allocate before clearing use_cid_lock. Only care about
3404 	 * program order because this is for forward progress.
3405 	 */
3406 	barrier();
3407 	WRITE_ONCE(use_cid_lock, 0);
3408 unlock:
3409 	raw_spin_unlock(&cid_lock);
3410 end:
3411 	mm_cid_snapshot_time(rq, mm);
3412 	return cid;
3413 }
3414 
3415 static inline int mm_cid_get(struct rq *rq, struct mm_struct *mm)
3416 {
3417 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3418 	struct cpumask *cpumask;
3419 	int cid;
3420 
3421 	lockdep_assert_rq_held(rq);
3422 	cpumask = mm_cidmask(mm);
3423 	cid = __this_cpu_read(pcpu_cid->cid);
3424 	if (mm_cid_is_valid(cid)) {
3425 		mm_cid_snapshot_time(rq, mm);
3426 		return cid;
3427 	}
3428 	if (mm_cid_is_lazy_put(cid)) {
3429 		if (try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET))
3430 			__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3431 	}
3432 	cid = __mm_cid_get(rq, mm);
3433 	__this_cpu_write(pcpu_cid->cid, cid);
3434 	return cid;
3435 }
3436 
3437 static inline void switch_mm_cid(struct rq *rq,
3438 				 struct task_struct *prev,
3439 				 struct task_struct *next)
3440 {
3441 	/*
3442 	 * Provide a memory barrier between rq->curr store and load of
3443 	 * {prev,next}->mm->pcpu_cid[cpu] on rq->curr->mm transition.
3444 	 *
3445 	 * Should be adapted if context_switch() is modified.
3446 	 */
3447 	if (!next->mm) {                                // to kernel
3448 		/*
3449 		 * user -> kernel transition does not guarantee a barrier, but
3450 		 * we can use the fact that it performs an atomic operation in
3451 		 * mmgrab().
3452 		 */
3453 		if (prev->mm)                           // from user
3454 			smp_mb__after_mmgrab();
3455 		/*
3456 		 * kernel -> kernel transition does not change rq->curr->mm
3457 		 * state. It stays NULL.
3458 		 */
3459 	} else {                                        // to user
3460 		/*
3461 		 * kernel -> user transition does not provide a barrier
3462 		 * between rq->curr store and load of {prev,next}->mm->pcpu_cid[cpu].
3463 		 * Provide it here.
3464 		 */
3465 		if (!prev->mm)                          // from kernel
3466 			smp_mb();
3467 		/*
3468 		 * user -> user transition guarantees a memory barrier through
3469 		 * switch_mm() when current->mm changes. If current->mm is
3470 		 * unchanged, no barrier is needed.
3471 		 */
3472 	}
3473 	if (prev->mm_cid_active) {
3474 		mm_cid_snapshot_time(rq, prev->mm);
3475 		mm_cid_put_lazy(prev);
3476 		prev->mm_cid = -1;
3477 	}
3478 	if (next->mm_cid_active)
3479 		next->last_mm_cid = next->mm_cid = mm_cid_get(rq, next->mm);
3480 }
3481 
3482 #else
3483 static inline void switch_mm_cid(struct rq *rq, struct task_struct *prev, struct task_struct *next) { }
3484 static inline void sched_mm_cid_migrate_from(struct task_struct *t) { }
3485 static inline void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t) { }
3486 static inline void task_tick_mm_cid(struct rq *rq, struct task_struct *curr) { }
3487 static inline void init_sched_mm_cid(struct task_struct *t) { }
3488 #endif
3489 
3490 #endif /* _KERNEL_SCHED_SCHED_H */
3491