xref: /linux/kernel/sched/sched.h (revision 7fc2cd2e4b398c57c9cf961cfea05eadbf34c05c)
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/prandom.h>
9 #include <linux/sched/affinity.h>
10 #include <linux/sched/autogroup.h>
11 #include <linux/sched/cpufreq.h>
12 #include <linux/sched/deadline.h>
13 #include <linux/sched.h>
14 #include <linux/sched/loadavg.h>
15 #include <linux/sched/mm.h>
16 #include <linux/sched/rseq_api.h>
17 #include <linux/sched/signal.h>
18 #include <linux/sched/smt.h>
19 #include <linux/sched/stat.h>
20 #include <linux/sched/sysctl.h>
21 #include <linux/sched/task_flags.h>
22 #include <linux/sched/task.h>
23 #include <linux/sched/topology.h>
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 #include <linux/delayacct.h>
72 #include <linux/mmu_context.h>
73 
74 #include <trace/events/power.h>
75 #include <trace/events/sched.h>
76 
77 #include "../workqueue_internal.h"
78 
79 struct rq;
80 struct cfs_rq;
81 struct rt_rq;
82 struct sched_group;
83 struct cpuidle_state;
84 
85 #ifdef CONFIG_PARAVIRT
86 # include <asm/paravirt.h>
87 # include <asm/paravirt_api_clock.h>
88 #endif
89 
90 #include <asm/barrier.h>
91 
92 #include "cpupri.h"
93 #include "cpudeadline.h"
94 
95 /* task_struct::on_rq states: */
96 #define TASK_ON_RQ_QUEUED	1
97 #define TASK_ON_RQ_MIGRATING	2
98 
99 extern __read_mostly int scheduler_running;
100 
101 extern unsigned long calc_load_update;
102 extern atomic_long_t calc_load_tasks;
103 
104 extern void calc_global_load_tick(struct rq *this_rq);
105 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
106 
107 extern void call_trace_sched_update_nr_running(struct rq *rq, int count);
108 
109 extern int sysctl_sched_rt_period;
110 extern int sysctl_sched_rt_runtime;
111 extern int sched_rr_timeslice;
112 
113 /*
114  * Asymmetric CPU capacity bits
115  */
116 struct asym_cap_data {
117 	struct list_head link;
118 	struct rcu_head rcu;
119 	unsigned long capacity;
120 	unsigned long cpus[];
121 };
122 
123 extern struct list_head asym_cap_list;
124 
125 #define cpu_capacity_span(asym_data) to_cpumask((asym_data)->cpus)
126 
127 /*
128  * Helpers for converting nanosecond timing to jiffy resolution
129  */
130 #define NS_TO_JIFFIES(time)	((unsigned long)(time) / (NSEC_PER_SEC/HZ))
131 
132 /*
133  * Increase resolution of nice-level calculations for 64-bit architectures.
134  * The extra resolution improves shares distribution and load balancing of
135  * low-weight task groups (eg. nice +19 on an autogroup), deeper task-group
136  * hierarchies, especially on larger systems. This is not a user-visible change
137  * and does not change the user-interface for setting shares/weights.
138  *
139  * We increase resolution only if we have enough bits to allow this increased
140  * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
141  * are pretty high and the returns do not justify the increased costs.
142  *
143  * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
144  * increase coverage and consistency always enable it on 64-bit platforms.
145  */
146 #ifdef CONFIG_64BIT
147 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
148 # define scale_load(w)		((w) << SCHED_FIXEDPOINT_SHIFT)
149 # define scale_load_down(w)					\
150 ({								\
151 	unsigned long __w = (w);				\
152 								\
153 	if (__w)						\
154 		__w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT);	\
155 	__w;							\
156 })
157 #else
158 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT)
159 # define scale_load(w)		(w)
160 # define scale_load_down(w)	(w)
161 #endif
162 
163 /*
164  * Task weight (visible to users) and its load (invisible to users) have
165  * independent resolution, but they should be well calibrated. We use
166  * scale_load() and scale_load_down(w) to convert between them. The
167  * following must be true:
168  *
169  *  scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD
170  *
171  */
172 #define NICE_0_LOAD		(1L << NICE_0_LOAD_SHIFT)
173 
174 /*
175  * Single value that decides SCHED_DEADLINE internal math precision.
176  * 10 -> just above 1us
177  * 9  -> just above 0.5us
178  */
179 #define DL_SCALE		10
180 
181 /*
182  * Single value that denotes runtime == period, ie unlimited time.
183  */
184 #define RUNTIME_INF		((u64)~0ULL)
185 
186 static inline int idle_policy(int policy)
187 {
188 	return policy == SCHED_IDLE;
189 }
190 
191 static inline int normal_policy(int policy)
192 {
193 #ifdef CONFIG_SCHED_CLASS_EXT
194 	if (policy == SCHED_EXT)
195 		return true;
196 #endif
197 	return policy == SCHED_NORMAL;
198 }
199 
200 static inline int fair_policy(int policy)
201 {
202 	return normal_policy(policy) || policy == SCHED_BATCH;
203 }
204 
205 static inline int rt_policy(int policy)
206 {
207 	return policy == SCHED_FIFO || policy == SCHED_RR;
208 }
209 
210 static inline int dl_policy(int policy)
211 {
212 	return policy == SCHED_DEADLINE;
213 }
214 
215 static inline bool valid_policy(int policy)
216 {
217 	return idle_policy(policy) || fair_policy(policy) ||
218 		rt_policy(policy) || dl_policy(policy);
219 }
220 
221 static inline int task_has_idle_policy(struct task_struct *p)
222 {
223 	return idle_policy(p->policy);
224 }
225 
226 static inline int task_has_rt_policy(struct task_struct *p)
227 {
228 	return rt_policy(p->policy);
229 }
230 
231 static inline int task_has_dl_policy(struct task_struct *p)
232 {
233 	return dl_policy(p->policy);
234 }
235 
236 #define cap_scale(v, s)		((v)*(s) >> SCHED_CAPACITY_SHIFT)
237 
238 static inline void update_avg(u64 *avg, u64 sample)
239 {
240 	s64 diff = sample - *avg;
241 
242 	*avg += diff / 8;
243 }
244 
245 /*
246  * Shifting a value by an exponent greater *or equal* to the size of said value
247  * is UB; cap at size-1.
248  */
249 #define shr_bound(val, shift)							\
250 	(val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1))
251 
252 /*
253  * cgroup weight knobs should use the common MIN, DFL and MAX values which are
254  * 1, 100 and 10000 respectively. While it loses a bit of range on both ends, it
255  * maps pretty well onto the shares value used by scheduler and the round-trip
256  * conversions preserve the original value over the entire range.
257  */
258 static inline unsigned long sched_weight_from_cgroup(unsigned long cgrp_weight)
259 {
260 	return DIV_ROUND_CLOSEST_ULL(cgrp_weight * 1024, CGROUP_WEIGHT_DFL);
261 }
262 
263 static inline unsigned long sched_weight_to_cgroup(unsigned long weight)
264 {
265 	return clamp_t(unsigned long,
266 		       DIV_ROUND_CLOSEST_ULL(weight * CGROUP_WEIGHT_DFL, 1024),
267 		       CGROUP_WEIGHT_MIN, CGROUP_WEIGHT_MAX);
268 }
269 
270 /*
271  * !! For sched_setattr_nocheck() (kernel) only !!
272  *
273  * This is actually gross. :(
274  *
275  * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
276  * tasks, but still be able to sleep. We need this on platforms that cannot
277  * atomically change clock frequency. Remove once fast switching will be
278  * available on such platforms.
279  *
280  * SUGOV stands for SchedUtil GOVernor.
281  */
282 #define SCHED_FLAG_SUGOV	0x10000000
283 
284 #define SCHED_DL_FLAGS		(SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV)
285 
286 static inline bool dl_entity_is_special(const struct sched_dl_entity *dl_se)
287 {
288 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
289 	return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
290 #else
291 	return false;
292 #endif
293 }
294 
295 /*
296  * Tells if entity @a should preempt entity @b.
297  */
298 static inline bool dl_entity_preempt(const struct sched_dl_entity *a,
299 				     const struct sched_dl_entity *b)
300 {
301 	return dl_entity_is_special(a) ||
302 	       dl_time_before(a->deadline, b->deadline);
303 }
304 
305 /*
306  * This is the priority-queue data structure of the RT scheduling class:
307  */
308 struct rt_prio_array {
309 	DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
310 	struct list_head queue[MAX_RT_PRIO];
311 };
312 
313 struct rt_bandwidth {
314 	/* nests inside the rq lock: */
315 	raw_spinlock_t		rt_runtime_lock;
316 	ktime_t			rt_period;
317 	u64			rt_runtime;
318 	struct hrtimer		rt_period_timer;
319 	unsigned int		rt_period_active;
320 };
321 
322 static inline int dl_bandwidth_enabled(void)
323 {
324 	return sysctl_sched_rt_runtime >= 0;
325 }
326 
327 /*
328  * To keep the bandwidth of -deadline tasks under control
329  * we need some place where:
330  *  - store the maximum -deadline bandwidth of each cpu;
331  *  - cache the fraction of bandwidth that is currently allocated in
332  *    each root domain;
333  *
334  * This is all done in the data structure below. It is similar to the
335  * one used for RT-throttling (rt_bandwidth), with the main difference
336  * that, since here we are only interested in admission control, we
337  * do not decrease any runtime while the group "executes", neither we
338  * need a timer to replenish it.
339  *
340  * With respect to SMP, bandwidth is given on a per root domain basis,
341  * meaning that:
342  *  - bw (< 100%) is the deadline bandwidth of each CPU;
343  *  - total_bw is the currently allocated bandwidth in each root domain;
344  */
345 struct dl_bw {
346 	raw_spinlock_t		lock;
347 	u64			bw;
348 	u64			total_bw;
349 };
350 
351 extern void init_dl_bw(struct dl_bw *dl_b);
352 extern int  sched_dl_global_validate(void);
353 extern void sched_dl_do_global(void);
354 extern int  sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
355 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
356 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
357 extern bool __checkparam_dl(const struct sched_attr *attr);
358 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
359 extern int  dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
360 extern int  dl_bw_deactivate(int cpu);
361 extern s64 dl_scaled_delta_exec(struct rq *rq, struct sched_dl_entity *dl_se, s64 delta_exec);
362 /*
363  * SCHED_DEADLINE supports servers (nested scheduling) with the following
364  * interface:
365  *
366  *   dl_se::rq -- runqueue we belong to.
367  *
368  *   dl_se::server_pick() -- nested pick_next_task(); we yield the period if this
369  *                           returns NULL.
370  *
371  *   dl_server_update() -- called from update_curr_common(), propagates runtime
372  *                         to the server.
373  *
374  *   dl_server_start() -- start the server when it has tasks; it will stop
375  *			  automatically when there are no more tasks, per
376  *			  dl_se::server_pick() returning NULL.
377  *
378  *   dl_server_stop() -- (force) stop the server; use when updating
379  *                       parameters.
380  *
381  *   dl_server_init() -- initializes the server.
382  *
383  * When started the dl_server will (per dl_defer) schedule a timer for its
384  * zero-laxity point -- that is, unlike regular EDF tasks which run ASAP, a
385  * server will run at the very end of its period.
386  *
387  * This is done such that any runtime from the target class can be accounted
388  * against the server -- through dl_server_update() above -- such that when it
389  * becomes time to run, it might already be out of runtime and get deferred
390  * until the next period. In this case dl_server_timer() will alternate
391  * between defer and replenish but never actually enqueue the server.
392  *
393  * Only when the target class does not manage to exhaust the server's runtime
394  * (there's actualy starvation in the given period), will the dl_server get on
395  * the runqueue. Once queued it will pick tasks from the target class and run
396  * them until either its runtime is exhaused, at which point its back to
397  * dl_server_timer, or until there are no more tasks to run, at which point
398  * the dl_server stops itself.
399  *
400  * By stopping at this point the dl_server retains bandwidth, which, if a new
401  * task wakes up imminently (starting the server again), can be used --
402  * subject to CBS wakeup rules -- without having to wait for the next period.
403  *
404  * Additionally, because of the dl_defer behaviour the start/stop behaviour is
405  * naturally thottled to once per period, avoiding high context switch
406  * workloads from spamming the hrtimer program/cancel paths.
407  */
408 extern void dl_server_update_idle(struct sched_dl_entity *dl_se, s64 delta_exec);
409 extern void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec);
410 extern void dl_server_start(struct sched_dl_entity *dl_se);
411 extern void dl_server_stop(struct sched_dl_entity *dl_se);
412 extern void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq,
413 		    dl_server_pick_f pick_task);
414 extern void sched_init_dl_servers(void);
415 
416 extern void fair_server_init(struct rq *rq);
417 extern void __dl_server_attach_root(struct sched_dl_entity *dl_se, struct rq *rq);
418 extern int dl_server_apply_params(struct sched_dl_entity *dl_se,
419 		    u64 runtime, u64 period, bool init);
420 
421 static inline bool dl_server_active(struct sched_dl_entity *dl_se)
422 {
423 	return dl_se->dl_server_active;
424 }
425 
426 #ifdef CONFIG_CGROUP_SCHED
427 
428 extern struct list_head task_groups;
429 
430 #ifdef CONFIG_GROUP_SCHED_BANDWIDTH
431 extern const u64 max_bw_quota_period_us;
432 
433 /*
434  * default period for group bandwidth.
435  * default: 0.1s, units: microseconds
436  */
437 static inline u64 default_bw_period_us(void)
438 {
439 	return 100000ULL;
440 }
441 #endif /* CONFIG_GROUP_SCHED_BANDWIDTH */
442 
443 struct cfs_bandwidth {
444 #ifdef CONFIG_CFS_BANDWIDTH
445 	raw_spinlock_t		lock;
446 	ktime_t			period;
447 	u64			quota;
448 	u64			runtime;
449 	u64			burst;
450 	u64			runtime_snap;
451 	s64			hierarchical_quota;
452 
453 	u8			idle;
454 	u8			period_active;
455 	u8			slack_started;
456 	struct hrtimer		period_timer;
457 	struct hrtimer		slack_timer;
458 	struct list_head	throttled_cfs_rq;
459 
460 	/* Statistics: */
461 	int			nr_periods;
462 	int			nr_throttled;
463 	int			nr_burst;
464 	u64			throttled_time;
465 	u64			burst_time;
466 #endif /* CONFIG_CFS_BANDWIDTH */
467 };
468 
469 /* Task group related information */
470 struct task_group {
471 	struct cgroup_subsys_state css;
472 
473 #ifdef CONFIG_GROUP_SCHED_WEIGHT
474 	/* A positive value indicates that this is a SCHED_IDLE group. */
475 	int			idle;
476 #endif
477 
478 #ifdef CONFIG_FAIR_GROUP_SCHED
479 	/* schedulable entities of this group on each CPU */
480 	struct sched_entity	**se;
481 	/* runqueue "owned" by this group on each CPU */
482 	struct cfs_rq		**cfs_rq;
483 	unsigned long		shares;
484 	/*
485 	 * load_avg can be heavily contended at clock tick time, so put
486 	 * it in its own cache-line separated from the fields above which
487 	 * will also be accessed at each tick.
488 	 */
489 	atomic_long_t		load_avg ____cacheline_aligned;
490 #endif /* CONFIG_FAIR_GROUP_SCHED */
491 
492 #ifdef CONFIG_RT_GROUP_SCHED
493 	struct sched_rt_entity	**rt_se;
494 	struct rt_rq		**rt_rq;
495 
496 	struct rt_bandwidth	rt_bandwidth;
497 #endif
498 
499 	struct scx_task_group	scx;
500 
501 	struct rcu_head		rcu;
502 	struct list_head	list;
503 
504 	struct task_group	*parent;
505 	struct list_head	siblings;
506 	struct list_head	children;
507 
508 #ifdef CONFIG_SCHED_AUTOGROUP
509 	struct autogroup	*autogroup;
510 #endif
511 
512 	struct cfs_bandwidth	cfs_bandwidth;
513 
514 #ifdef CONFIG_UCLAMP_TASK_GROUP
515 	/* The two decimal precision [%] value requested from user-space */
516 	unsigned int		uclamp_pct[UCLAMP_CNT];
517 	/* Clamp values requested for a task group */
518 	struct uclamp_se	uclamp_req[UCLAMP_CNT];
519 	/* Effective clamp values used for a task group */
520 	struct uclamp_se	uclamp[UCLAMP_CNT];
521 #endif
522 
523 };
524 
525 #ifdef CONFIG_GROUP_SCHED_WEIGHT
526 #define ROOT_TASK_GROUP_LOAD	NICE_0_LOAD
527 
528 /*
529  * A weight of 0 or 1 can cause arithmetics problems.
530  * A weight of a cfs_rq is the sum of weights of which entities
531  * are queued on this cfs_rq, so a weight of a entity should not be
532  * too large, so as the shares value of a task group.
533  * (The default weight is 1024 - so there's no practical
534  *  limitation from this.)
535  */
536 #define MIN_SHARES		(1UL <<  1)
537 #define MAX_SHARES		(1UL << 18)
538 #endif
539 
540 typedef int (*tg_visitor)(struct task_group *, void *);
541 
542 extern int walk_tg_tree_from(struct task_group *from,
543 			     tg_visitor down, tg_visitor up, void *data);
544 
545 /*
546  * Iterate the full tree, calling @down when first entering a node and @up when
547  * leaving it for the final time.
548  *
549  * Caller must hold rcu_lock or sufficient equivalent.
550  */
551 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
552 {
553 	return walk_tg_tree_from(&root_task_group, down, up, data);
554 }
555 
556 static inline struct task_group *css_tg(struct cgroup_subsys_state *css)
557 {
558 	return css ? container_of(css, struct task_group, css) : NULL;
559 }
560 
561 extern int tg_nop(struct task_group *tg, void *data);
562 
563 #ifdef CONFIG_FAIR_GROUP_SCHED
564 extern void free_fair_sched_group(struct task_group *tg);
565 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
566 extern void online_fair_sched_group(struct task_group *tg);
567 extern void unregister_fair_sched_group(struct task_group *tg);
568 #else /* !CONFIG_FAIR_GROUP_SCHED: */
569 static inline void free_fair_sched_group(struct task_group *tg) { }
570 static inline int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
571 {
572        return 1;
573 }
574 static inline void online_fair_sched_group(struct task_group *tg) { }
575 static inline void unregister_fair_sched_group(struct task_group *tg) { }
576 #endif /* !CONFIG_FAIR_GROUP_SCHED */
577 
578 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
579 			struct sched_entity *se, int cpu,
580 			struct sched_entity *parent);
581 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b, struct cfs_bandwidth *parent);
582 
583 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
584 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
585 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
586 extern bool cfs_task_bw_constrained(struct task_struct *p);
587 
588 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
589 		struct sched_rt_entity *rt_se, int cpu,
590 		struct sched_rt_entity *parent);
591 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
592 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
593 extern long sched_group_rt_runtime(struct task_group *tg);
594 extern long sched_group_rt_period(struct task_group *tg);
595 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
596 
597 extern struct task_group *sched_create_group(struct task_group *parent);
598 extern void sched_online_group(struct task_group *tg,
599 			       struct task_group *parent);
600 extern void sched_destroy_group(struct task_group *tg);
601 extern void sched_release_group(struct task_group *tg);
602 
603 extern void sched_move_task(struct task_struct *tsk, bool for_autogroup);
604 
605 #ifdef CONFIG_FAIR_GROUP_SCHED
606 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
607 
608 extern int sched_group_set_idle(struct task_group *tg, long idle);
609 
610 extern void set_task_rq_fair(struct sched_entity *se,
611 			     struct cfs_rq *prev, struct cfs_rq *next);
612 #else /* !CONFIG_FAIR_GROUP_SCHED: */
613 static inline int sched_group_set_shares(struct task_group *tg, unsigned long shares) { return 0; }
614 static inline int sched_group_set_idle(struct task_group *tg, long idle) { return 0; }
615 #endif /* !CONFIG_FAIR_GROUP_SCHED */
616 
617 #else /* !CONFIG_CGROUP_SCHED: */
618 
619 struct cfs_bandwidth { };
620 
621 static inline bool cfs_task_bw_constrained(struct task_struct *p) { return false; }
622 
623 #endif /* !CONFIG_CGROUP_SCHED */
624 
625 extern void unregister_rt_sched_group(struct task_group *tg);
626 extern void free_rt_sched_group(struct task_group *tg);
627 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
628 
629 /*
630  * u64_u32_load/u64_u32_store
631  *
632  * Use a copy of a u64 value to protect against data race. This is only
633  * applicable for 32-bits architectures.
634  */
635 #ifdef CONFIG_64BIT
636 # define u64_u32_load_copy(var, copy)		var
637 # define u64_u32_store_copy(var, copy, val)	(var = val)
638 #else
639 # define u64_u32_load_copy(var, copy)					\
640 ({									\
641 	u64 __val, __val_copy;						\
642 	do {								\
643 		__val_copy = copy;					\
644 		/*							\
645 		 * paired with u64_u32_store_copy(), ordering access	\
646 		 * to var and copy.					\
647 		 */							\
648 		smp_rmb();						\
649 		__val = var;						\
650 	} while (__val != __val_copy);					\
651 	__val;								\
652 })
653 # define u64_u32_store_copy(var, copy, val)				\
654 do {									\
655 	typeof(val) __val = (val);					\
656 	var = __val;							\
657 	/*								\
658 	 * paired with u64_u32_load_copy(), ordering access to var and	\
659 	 * copy.							\
660 	 */								\
661 	smp_wmb();							\
662 	copy = __val;							\
663 } while (0)
664 #endif
665 # define u64_u32_load(var)		u64_u32_load_copy(var, var##_copy)
666 # define u64_u32_store(var, val)	u64_u32_store_copy(var, var##_copy, val)
667 
668 struct balance_callback {
669 	struct balance_callback *next;
670 	void (*func)(struct rq *rq);
671 };
672 
673 /* CFS-related fields in a runqueue */
674 struct cfs_rq {
675 	struct load_weight	load;
676 	unsigned int		nr_queued;
677 	unsigned int		h_nr_queued;       /* SCHED_{NORMAL,BATCH,IDLE} */
678 	unsigned int		h_nr_runnable;     /* SCHED_{NORMAL,BATCH,IDLE} */
679 	unsigned int		h_nr_idle; /* SCHED_IDLE */
680 
681 	s64			avg_vruntime;
682 	u64			avg_load;
683 
684 	u64			zero_vruntime;
685 #ifdef CONFIG_SCHED_CORE
686 	unsigned int		forceidle_seq;
687 	u64			zero_vruntime_fi;
688 #endif
689 
690 	struct rb_root_cached	tasks_timeline;
691 
692 	/*
693 	 * 'curr' points to currently running entity on this cfs_rq.
694 	 * It is set to NULL otherwise (i.e when none are currently running).
695 	 */
696 	struct sched_entity	*curr;
697 	struct sched_entity	*next;
698 
699 	/*
700 	 * CFS load tracking
701 	 */
702 	struct sched_avg	avg;
703 #ifndef CONFIG_64BIT
704 	u64			last_update_time_copy;
705 #endif
706 	struct {
707 		raw_spinlock_t	lock ____cacheline_aligned;
708 		int		nr;
709 		unsigned long	load_avg;
710 		unsigned long	util_avg;
711 		unsigned long	runnable_avg;
712 	} removed;
713 
714 #ifdef CONFIG_FAIR_GROUP_SCHED
715 	u64			last_update_tg_load_avg;
716 	unsigned long		tg_load_avg_contrib;
717 	long			propagate;
718 	long			prop_runnable_sum;
719 
720 	/*
721 	 *   h_load = weight * f(tg)
722 	 *
723 	 * Where f(tg) is the recursive weight fraction assigned to
724 	 * this group.
725 	 */
726 	unsigned long		h_load;
727 	u64			last_h_load_update;
728 	struct sched_entity	*h_load_next;
729 #endif /* CONFIG_FAIR_GROUP_SCHED */
730 
731 #ifdef CONFIG_FAIR_GROUP_SCHED
732 	struct rq		*rq;	/* CPU runqueue to which this cfs_rq is attached */
733 
734 	/*
735 	 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
736 	 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
737 	 * (like users, containers etc.)
738 	 *
739 	 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
740 	 * This list is used during load balance.
741 	 */
742 	int			on_list;
743 	struct list_head	leaf_cfs_rq_list;
744 	struct task_group	*tg;	/* group that "owns" this runqueue */
745 
746 	/* Locally cached copy of our task_group's idle value */
747 	int			idle;
748 
749 #ifdef CONFIG_CFS_BANDWIDTH
750 	int			runtime_enabled;
751 	s64			runtime_remaining;
752 
753 	u64			throttled_pelt_idle;
754 #ifndef CONFIG_64BIT
755 	u64                     throttled_pelt_idle_copy;
756 #endif
757 	u64			throttled_clock;
758 	u64			throttled_clock_pelt;
759 	u64			throttled_clock_pelt_time;
760 	u64			throttled_clock_self;
761 	u64			throttled_clock_self_time;
762 	bool			throttled:1;
763 	bool			pelt_clock_throttled:1;
764 	int			throttle_count;
765 	struct list_head	throttled_list;
766 	struct list_head	throttled_csd_list;
767 	struct list_head        throttled_limbo_list;
768 #endif /* CONFIG_CFS_BANDWIDTH */
769 #endif /* CONFIG_FAIR_GROUP_SCHED */
770 };
771 
772 #ifdef CONFIG_SCHED_CLASS_EXT
773 /* scx_rq->flags, protected by the rq lock */
774 enum scx_rq_flags {
775 	/*
776 	 * A hotplugged CPU starts scheduling before rq_online_scx(). Track
777 	 * ops.cpu_on/offline() state so that ops.enqueue/dispatch() are called
778 	 * only while the BPF scheduler considers the CPU to be online.
779 	 */
780 	SCX_RQ_ONLINE		= 1 << 0,
781 	SCX_RQ_CAN_STOP_TICK	= 1 << 1,
782 	SCX_RQ_BAL_KEEP		= 1 << 3, /* balance decided to keep current */
783 	SCX_RQ_BYPASSING	= 1 << 4,
784 	SCX_RQ_CLK_VALID	= 1 << 5, /* RQ clock is fresh and valid */
785 	SCX_RQ_BAL_CB_PENDING	= 1 << 6, /* must queue a cb after dispatching */
786 
787 	SCX_RQ_IN_WAKEUP	= 1 << 16,
788 	SCX_RQ_IN_BALANCE	= 1 << 17,
789 };
790 
791 struct scx_rq {
792 	struct scx_dispatch_q	local_dsq;
793 	struct list_head	runnable_list;		/* runnable tasks on this rq */
794 	struct list_head	ddsp_deferred_locals;	/* deferred ddsps from enq */
795 	unsigned long		ops_qseq;
796 	u64			extra_enq_flags;	/* see move_task_to_local_dsq() */
797 	u32			nr_running;
798 	u32			cpuperf_target;		/* [0, SCHED_CAPACITY_SCALE] */
799 	bool			cpu_released;
800 	u32			flags;
801 	u64			clock;			/* current per-rq clock -- see scx_bpf_now() */
802 	cpumask_var_t		cpus_to_kick;
803 	cpumask_var_t		cpus_to_kick_if_idle;
804 	cpumask_var_t		cpus_to_preempt;
805 	cpumask_var_t		cpus_to_wait;
806 	unsigned long		pnt_seq;
807 	struct balance_callback	deferred_bal_cb;
808 	struct irq_work		deferred_irq_work;
809 	struct irq_work		kick_cpus_irq_work;
810 };
811 #endif /* CONFIG_SCHED_CLASS_EXT */
812 
813 static inline int rt_bandwidth_enabled(void)
814 {
815 	return sysctl_sched_rt_runtime >= 0;
816 }
817 
818 /* RT IPI pull logic requires IRQ_WORK */
819 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
820 # define HAVE_RT_PUSH_IPI
821 #endif
822 
823 /* Real-Time classes' related field in a runqueue: */
824 struct rt_rq {
825 	struct rt_prio_array	active;
826 	unsigned int		rt_nr_running;
827 	unsigned int		rr_nr_running;
828 	struct {
829 		int		curr; /* highest queued rt task prio */
830 		int		next; /* next highest */
831 	} highest_prio;
832 	bool			overloaded;
833 	struct plist_head	pushable_tasks;
834 
835 	int			rt_queued;
836 
837 #ifdef CONFIG_RT_GROUP_SCHED
838 	int			rt_throttled;
839 	u64			rt_time; /* consumed RT time, goes up in update_curr_rt */
840 	u64			rt_runtime; /* allotted RT time, "slice" from rt_bandwidth, RT sharing/balancing */
841 	/* Nests inside the rq lock: */
842 	raw_spinlock_t		rt_runtime_lock;
843 
844 	unsigned int		rt_nr_boosted;
845 
846 	struct rq		*rq; /* this is always top-level rq, cache? */
847 #endif
848 #ifdef CONFIG_CGROUP_SCHED
849 	struct task_group	*tg; /* this tg has "this" rt_rq on given CPU for runnable entities */
850 #endif
851 };
852 
853 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
854 {
855 	return rt_rq->rt_queued && rt_rq->rt_nr_running;
856 }
857 
858 /* Deadline class' related fields in a runqueue */
859 struct dl_rq {
860 	/* runqueue is an rbtree, ordered by deadline */
861 	struct rb_root_cached	root;
862 
863 	unsigned int		dl_nr_running;
864 
865 	/*
866 	 * Deadline values of the currently executing and the
867 	 * earliest ready task on this rq. Caching these facilitates
868 	 * the decision whether or not a ready but not running task
869 	 * should migrate somewhere else.
870 	 */
871 	struct {
872 		u64		curr;
873 		u64		next;
874 	} earliest_dl;
875 
876 	bool			overloaded;
877 
878 	/*
879 	 * Tasks on this rq that can be pushed away. They are kept in
880 	 * an rb-tree, ordered by tasks' deadlines, with caching
881 	 * of the leftmost (earliest deadline) element.
882 	 */
883 	struct rb_root_cached	pushable_dl_tasks_root;
884 
885 	/*
886 	 * "Active utilization" for this runqueue: increased when a
887 	 * task wakes up (becomes TASK_RUNNING) and decreased when a
888 	 * task blocks
889 	 */
890 	u64			running_bw;
891 
892 	/*
893 	 * Utilization of the tasks "assigned" to this runqueue (including
894 	 * the tasks that are in runqueue and the tasks that executed on this
895 	 * CPU and blocked). Increased when a task moves to this runqueue, and
896 	 * decreased when the task moves away (migrates, changes scheduling
897 	 * policy, or terminates).
898 	 * This is needed to compute the "inactive utilization" for the
899 	 * runqueue (inactive utilization = this_bw - running_bw).
900 	 */
901 	u64			this_bw;
902 	u64			extra_bw;
903 
904 	/*
905 	 * Maximum available bandwidth for reclaiming by SCHED_FLAG_RECLAIM
906 	 * tasks of this rq. Used in calculation of reclaimable bandwidth(GRUB).
907 	 */
908 	u64			max_bw;
909 
910 	/*
911 	 * Inverse of the fraction of CPU utilization that can be reclaimed
912 	 * by the GRUB algorithm.
913 	 */
914 	u64			bw_ratio;
915 };
916 
917 #ifdef CONFIG_FAIR_GROUP_SCHED
918 
919 /* An entity is a task if it doesn't "own" a runqueue */
920 #define entity_is_task(se)	(!se->my_q)
921 
922 static inline void se_update_runnable(struct sched_entity *se)
923 {
924 	if (!entity_is_task(se))
925 		se->runnable_weight = se->my_q->h_nr_runnable;
926 }
927 
928 static inline long se_runnable(struct sched_entity *se)
929 {
930 	if (se->sched_delayed)
931 		return false;
932 
933 	if (entity_is_task(se))
934 		return !!se->on_rq;
935 	else
936 		return se->runnable_weight;
937 }
938 
939 #else /* !CONFIG_FAIR_GROUP_SCHED: */
940 
941 #define entity_is_task(se)	1
942 
943 static inline void se_update_runnable(struct sched_entity *se) { }
944 
945 static inline long se_runnable(struct sched_entity *se)
946 {
947 	if (se->sched_delayed)
948 		return false;
949 
950 	return !!se->on_rq;
951 }
952 
953 #endif /* !CONFIG_FAIR_GROUP_SCHED */
954 
955 /*
956  * XXX we want to get rid of these helpers and use the full load resolution.
957  */
958 static inline long se_weight(struct sched_entity *se)
959 {
960 	return scale_load_down(se->load.weight);
961 }
962 
963 
964 static inline bool sched_asym_prefer(int a, int b)
965 {
966 	return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
967 }
968 
969 struct perf_domain {
970 	struct em_perf_domain *em_pd;
971 	struct perf_domain *next;
972 	struct rcu_head rcu;
973 };
974 
975 /*
976  * We add the notion of a root-domain which will be used to define per-domain
977  * variables. Each exclusive cpuset essentially defines an island domain by
978  * fully partitioning the member CPUs from any other cpuset. Whenever a new
979  * exclusive cpuset is created, we also create and attach a new root-domain
980  * object.
981  *
982  */
983 struct root_domain {
984 	atomic_t		refcount;
985 	atomic_t		rto_count;
986 	struct rcu_head		rcu;
987 	cpumask_var_t		span;
988 	cpumask_var_t		online;
989 
990 	/*
991 	 * Indicate pullable load on at least one CPU, e.g:
992 	 * - More than one runnable task
993 	 * - Running task is misfit
994 	 */
995 	bool			overloaded;
996 
997 	/* Indicate one or more CPUs over-utilized (tipping point) */
998 	bool			overutilized;
999 
1000 	/*
1001 	 * The bit corresponding to a CPU gets set here if such CPU has more
1002 	 * than one runnable -deadline task (as it is below for RT tasks).
1003 	 */
1004 	cpumask_var_t		dlo_mask;
1005 	atomic_t		dlo_count;
1006 	struct dl_bw		dl_bw;
1007 	struct cpudl		cpudl;
1008 
1009 	/*
1010 	 * Indicate whether a root_domain's dl_bw has been checked or
1011 	 * updated. It's monotonously increasing value.
1012 	 *
1013 	 * Also, some corner cases, like 'wrap around' is dangerous, but given
1014 	 * that u64 is 'big enough'. So that shouldn't be a concern.
1015 	 */
1016 	u64 visit_cookie;
1017 
1018 #ifdef HAVE_RT_PUSH_IPI
1019 	/*
1020 	 * For IPI pull requests, loop across the rto_mask.
1021 	 */
1022 	struct irq_work		rto_push_work;
1023 	raw_spinlock_t		rto_lock;
1024 	/* These are only updated and read within rto_lock */
1025 	int			rto_loop;
1026 	int			rto_cpu;
1027 	/* These atomics are updated outside of a lock */
1028 	atomic_t		rto_loop_next;
1029 	atomic_t		rto_loop_start;
1030 #endif /* HAVE_RT_PUSH_IPI */
1031 	/*
1032 	 * The "RT overload" flag: it gets set if a CPU has more than
1033 	 * one runnable RT task.
1034 	 */
1035 	cpumask_var_t		rto_mask;
1036 	struct cpupri		cpupri;
1037 
1038 	/*
1039 	 * NULL-terminated list of performance domains intersecting with the
1040 	 * CPUs of the rd. Protected by RCU.
1041 	 */
1042 	struct perf_domain __rcu *pd;
1043 };
1044 
1045 extern void init_defrootdomain(void);
1046 extern int sched_init_domains(const struct cpumask *cpu_map);
1047 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
1048 extern void sched_get_rd(struct root_domain *rd);
1049 extern void sched_put_rd(struct root_domain *rd);
1050 
1051 static inline int get_rd_overloaded(struct root_domain *rd)
1052 {
1053 	return READ_ONCE(rd->overloaded);
1054 }
1055 
1056 static inline void set_rd_overloaded(struct root_domain *rd, int status)
1057 {
1058 	if (get_rd_overloaded(rd) != status)
1059 		WRITE_ONCE(rd->overloaded, status);
1060 }
1061 
1062 #ifdef HAVE_RT_PUSH_IPI
1063 extern void rto_push_irq_work_func(struct irq_work *work);
1064 #endif
1065 
1066 #ifdef CONFIG_UCLAMP_TASK
1067 /*
1068  * struct uclamp_bucket - Utilization clamp bucket
1069  * @value: utilization clamp value for tasks on this clamp bucket
1070  * @tasks: number of RUNNABLE tasks on this clamp bucket
1071  *
1072  * Keep track of how many tasks are RUNNABLE for a given utilization
1073  * clamp value.
1074  */
1075 struct uclamp_bucket {
1076 	unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
1077 	unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
1078 };
1079 
1080 /*
1081  * struct uclamp_rq - rq's utilization clamp
1082  * @value: currently active clamp values for a rq
1083  * @bucket: utilization clamp buckets affecting a rq
1084  *
1085  * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
1086  * A clamp value is affecting a rq when there is at least one task RUNNABLE
1087  * (or actually running) with that value.
1088  *
1089  * There are up to UCLAMP_CNT possible different clamp values, currently there
1090  * are only two: minimum utilization and maximum utilization.
1091  *
1092  * All utilization clamping values are MAX aggregated, since:
1093  * - for util_min: we want to run the CPU at least at the max of the minimum
1094  *   utilization required by its currently RUNNABLE tasks.
1095  * - for util_max: we want to allow the CPU to run up to the max of the
1096  *   maximum utilization allowed by its currently RUNNABLE tasks.
1097  *
1098  * Since on each system we expect only a limited number of different
1099  * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
1100  * the metrics required to compute all the per-rq utilization clamp values.
1101  */
1102 struct uclamp_rq {
1103 	unsigned int value;
1104 	struct uclamp_bucket bucket[UCLAMP_BUCKETS];
1105 };
1106 
1107 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
1108 #endif /* CONFIG_UCLAMP_TASK */
1109 
1110 /*
1111  * This is the main, per-CPU runqueue data structure.
1112  *
1113  * Locking rule: those places that want to lock multiple runqueues
1114  * (such as the load balancing or the thread migration code), lock
1115  * acquire operations must be ordered by ascending &runqueue.
1116  */
1117 struct rq {
1118 	/* runqueue lock: */
1119 	raw_spinlock_t		__lock;
1120 
1121 	/* Per class runqueue modification mask; bits in class order. */
1122 	unsigned int		queue_mask;
1123 	unsigned int		nr_running;
1124 #ifdef CONFIG_NUMA_BALANCING
1125 	unsigned int		nr_numa_running;
1126 	unsigned int		nr_preferred_running;
1127 	unsigned int		numa_migrate_on;
1128 #endif
1129 #ifdef CONFIG_NO_HZ_COMMON
1130 	unsigned long		last_blocked_load_update_tick;
1131 	unsigned int		has_blocked_load;
1132 	call_single_data_t	nohz_csd;
1133 	unsigned int		nohz_tick_stopped;
1134 	atomic_t		nohz_flags;
1135 #endif /* CONFIG_NO_HZ_COMMON */
1136 
1137 	unsigned int		ttwu_pending;
1138 	u64			nr_switches;
1139 
1140 #ifdef CONFIG_UCLAMP_TASK
1141 	/* Utilization clamp values based on CPU's RUNNABLE tasks */
1142 	struct uclamp_rq	uclamp[UCLAMP_CNT] ____cacheline_aligned;
1143 	unsigned int		uclamp_flags;
1144 #define UCLAMP_FLAG_IDLE 0x01
1145 #endif
1146 
1147 	struct cfs_rq		cfs;
1148 	struct rt_rq		rt;
1149 	struct dl_rq		dl;
1150 #ifdef CONFIG_SCHED_CLASS_EXT
1151 	struct scx_rq		scx;
1152 #endif
1153 
1154 	struct sched_dl_entity	fair_server;
1155 
1156 #ifdef CONFIG_FAIR_GROUP_SCHED
1157 	/* list of leaf cfs_rq on this CPU: */
1158 	struct list_head	leaf_cfs_rq_list;
1159 	struct list_head	*tmp_alone_branch;
1160 #endif /* CONFIG_FAIR_GROUP_SCHED */
1161 
1162 	/*
1163 	 * This is part of a global counter where only the total sum
1164 	 * over all CPUs matters. A task can increase this counter on
1165 	 * one CPU and if it got migrated afterwards it may decrease
1166 	 * it on another CPU. Always updated under the runqueue lock:
1167 	 */
1168 	unsigned long 		nr_uninterruptible;
1169 
1170 #ifdef CONFIG_SCHED_PROXY_EXEC
1171 	struct task_struct __rcu	*donor;  /* Scheduling context */
1172 	struct task_struct __rcu	*curr;   /* Execution context */
1173 #else
1174 	union {
1175 		struct task_struct __rcu *donor; /* Scheduler context */
1176 		struct task_struct __rcu *curr;  /* Execution context */
1177 	};
1178 #endif
1179 	struct sched_dl_entity	*dl_server;
1180 	struct task_struct	*idle;
1181 	struct task_struct	*stop;
1182 	unsigned long		next_balance;
1183 	struct mm_struct	*prev_mm;
1184 
1185 	unsigned int		clock_update_flags;
1186 	u64			clock;
1187 	/* Ensure that all clocks are in the same cache line */
1188 	u64			clock_task ____cacheline_aligned;
1189 	u64			clock_pelt;
1190 	unsigned long		lost_idle_time;
1191 	u64			clock_pelt_idle;
1192 	u64			clock_idle;
1193 #ifndef CONFIG_64BIT
1194 	u64			clock_pelt_idle_copy;
1195 	u64			clock_idle_copy;
1196 #endif
1197 
1198 	atomic_t		nr_iowait;
1199 
1200 	u64 last_seen_need_resched_ns;
1201 	int ticks_without_resched;
1202 
1203 #ifdef CONFIG_MEMBARRIER
1204 	int membarrier_state;
1205 #endif
1206 
1207 	struct root_domain		*rd;
1208 	struct sched_domain __rcu	*sd;
1209 
1210 	unsigned long		cpu_capacity;
1211 
1212 	struct balance_callback *balance_callback;
1213 
1214 	unsigned char		nohz_idle_balance;
1215 	unsigned char		idle_balance;
1216 
1217 	unsigned long		misfit_task_load;
1218 
1219 	/* For active balancing */
1220 	int			active_balance;
1221 	int			push_cpu;
1222 	struct cpu_stop_work	active_balance_work;
1223 
1224 	/* CPU of this runqueue: */
1225 	int			cpu;
1226 	int			online;
1227 
1228 	struct list_head cfs_tasks;
1229 
1230 	struct sched_avg	avg_rt;
1231 	struct sched_avg	avg_dl;
1232 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1233 	struct sched_avg	avg_irq;
1234 #endif
1235 #ifdef CONFIG_SCHED_HW_PRESSURE
1236 	struct sched_avg	avg_hw;
1237 #endif
1238 	u64			idle_stamp;
1239 	u64			avg_idle;
1240 
1241 	/* This is used to determine avg_idle's max value */
1242 	u64			max_idle_balance_cost;
1243 
1244 #ifdef CONFIG_HOTPLUG_CPU
1245 	struct rcuwait		hotplug_wait;
1246 #endif
1247 
1248 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1249 	u64			prev_irq_time;
1250 	u64			psi_irq_time;
1251 #endif
1252 #ifdef CONFIG_PARAVIRT
1253 	u64			prev_steal_time;
1254 #endif
1255 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1256 	u64			prev_steal_time_rq;
1257 #endif
1258 
1259 	/* calc_load related fields */
1260 	unsigned long		calc_load_update;
1261 	long			calc_load_active;
1262 
1263 #ifdef CONFIG_SCHED_HRTICK
1264 	call_single_data_t	hrtick_csd;
1265 	struct hrtimer		hrtick_timer;
1266 	ktime_t			hrtick_time;
1267 #endif
1268 
1269 #ifdef CONFIG_SCHEDSTATS
1270 	/* latency stats */
1271 	struct sched_info	rq_sched_info;
1272 	unsigned long long	rq_cpu_time;
1273 
1274 	/* sys_sched_yield() stats */
1275 	unsigned int		yld_count;
1276 
1277 	/* schedule() stats */
1278 	unsigned int		sched_count;
1279 	unsigned int		sched_goidle;
1280 
1281 	/* try_to_wake_up() stats */
1282 	unsigned int		ttwu_count;
1283 	unsigned int		ttwu_local;
1284 #endif
1285 
1286 #ifdef CONFIG_CPU_IDLE
1287 	/* Must be inspected within a RCU lock section */
1288 	struct cpuidle_state	*idle_state;
1289 #endif
1290 
1291 	unsigned int		nr_pinned;
1292 	unsigned int		push_busy;
1293 	struct cpu_stop_work	push_work;
1294 
1295 #ifdef CONFIG_SCHED_CORE
1296 	/* per rq */
1297 	struct rq		*core;
1298 	struct task_struct	*core_pick;
1299 	struct sched_dl_entity	*core_dl_server;
1300 	unsigned int		core_enabled;
1301 	unsigned int		core_sched_seq;
1302 	struct rb_root		core_tree;
1303 
1304 	/* shared state -- careful with sched_core_cpu_deactivate() */
1305 	unsigned int		core_task_seq;
1306 	unsigned int		core_pick_seq;
1307 	unsigned long		core_cookie;
1308 	unsigned int		core_forceidle_count;
1309 	unsigned int		core_forceidle_seq;
1310 	unsigned int		core_forceidle_occupation;
1311 	u64			core_forceidle_start;
1312 #endif /* CONFIG_SCHED_CORE */
1313 
1314 	/* Scratch cpumask to be temporarily used under rq_lock */
1315 	cpumask_var_t		scratch_mask;
1316 
1317 #ifdef CONFIG_CFS_BANDWIDTH
1318 	call_single_data_t	cfsb_csd;
1319 	struct list_head	cfsb_csd_list;
1320 #endif
1321 };
1322 
1323 #ifdef CONFIG_FAIR_GROUP_SCHED
1324 
1325 /* CPU runqueue to which this cfs_rq is attached */
1326 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1327 {
1328 	return cfs_rq->rq;
1329 }
1330 
1331 #else /* !CONFIG_FAIR_GROUP_SCHED: */
1332 
1333 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1334 {
1335 	return container_of(cfs_rq, struct rq, cfs);
1336 }
1337 #endif /* !CONFIG_FAIR_GROUP_SCHED */
1338 
1339 static inline int cpu_of(struct rq *rq)
1340 {
1341 	return rq->cpu;
1342 }
1343 
1344 #define MDF_PUSH		0x01
1345 
1346 static inline bool is_migration_disabled(struct task_struct *p)
1347 {
1348 	return p->migration_disabled;
1349 }
1350 
1351 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1352 DECLARE_PER_CPU(struct rnd_state, sched_rnd_state);
1353 
1354 static inline u32 sched_rng(void)
1355 {
1356 	return prandom_u32_state(this_cpu_ptr(&sched_rnd_state));
1357 }
1358 
1359 #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
1360 #define this_rq()		this_cpu_ptr(&runqueues)
1361 #define task_rq(p)		cpu_rq(task_cpu(p))
1362 #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
1363 #define raw_rq()		raw_cpu_ptr(&runqueues)
1364 
1365 #ifdef CONFIG_SCHED_PROXY_EXEC
1366 static inline void rq_set_donor(struct rq *rq, struct task_struct *t)
1367 {
1368 	rcu_assign_pointer(rq->donor, t);
1369 }
1370 #else
1371 static inline void rq_set_donor(struct rq *rq, struct task_struct *t)
1372 {
1373 	/* Do nothing */
1374 }
1375 #endif
1376 
1377 #ifdef CONFIG_SCHED_CORE
1378 static inline struct cpumask *sched_group_span(struct sched_group *sg);
1379 
1380 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled);
1381 
1382 static inline bool sched_core_enabled(struct rq *rq)
1383 {
1384 	return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled;
1385 }
1386 
1387 static inline bool sched_core_disabled(void)
1388 {
1389 	return !static_branch_unlikely(&__sched_core_enabled);
1390 }
1391 
1392 /*
1393  * Be careful with this function; not for general use. The return value isn't
1394  * stable unless you actually hold a relevant rq->__lock.
1395  */
1396 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1397 {
1398 	if (sched_core_enabled(rq))
1399 		return &rq->core->__lock;
1400 
1401 	return &rq->__lock;
1402 }
1403 
1404 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1405 {
1406 	if (rq->core_enabled)
1407 		return &rq->core->__lock;
1408 
1409 	return &rq->__lock;
1410 }
1411 
1412 extern bool
1413 cfs_prio_less(const struct task_struct *a, const struct task_struct *b, bool fi);
1414 
1415 extern void task_vruntime_update(struct rq *rq, struct task_struct *p, bool in_fi);
1416 
1417 /*
1418  * Helpers to check if the CPU's core cookie matches with the task's cookie
1419  * when core scheduling is enabled.
1420  * A special case is that the task's cookie always matches with CPU's core
1421  * cookie if the CPU is in an idle core.
1422  */
1423 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1424 {
1425 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1426 	if (!sched_core_enabled(rq))
1427 		return true;
1428 
1429 	return rq->core->core_cookie == p->core_cookie;
1430 }
1431 
1432 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1433 {
1434 	bool idle_core = true;
1435 	int cpu;
1436 
1437 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1438 	if (!sched_core_enabled(rq))
1439 		return true;
1440 
1441 	if (rq->core->core_cookie == p->core_cookie)
1442 		return true;
1443 
1444 	for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) {
1445 		if (!available_idle_cpu(cpu)) {
1446 			idle_core = false;
1447 			break;
1448 		}
1449 	}
1450 
1451 	/*
1452 	 * A CPU in an idle core is always the best choice for tasks with
1453 	 * cookies.
1454 	 */
1455 	return idle_core;
1456 }
1457 
1458 static inline bool sched_group_cookie_match(struct rq *rq,
1459 					    struct task_struct *p,
1460 					    struct sched_group *group)
1461 {
1462 	int cpu;
1463 
1464 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1465 	if (!sched_core_enabled(rq))
1466 		return true;
1467 
1468 	for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
1469 		if (sched_core_cookie_match(cpu_rq(cpu), p))
1470 			return true;
1471 	}
1472 	return false;
1473 }
1474 
1475 static inline bool sched_core_enqueued(struct task_struct *p)
1476 {
1477 	return !RB_EMPTY_NODE(&p->core_node);
1478 }
1479 
1480 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p);
1481 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags);
1482 
1483 extern void sched_core_get(void);
1484 extern void sched_core_put(void);
1485 
1486 #else /* !CONFIG_SCHED_CORE: */
1487 
1488 static inline bool sched_core_enabled(struct rq *rq)
1489 {
1490 	return false;
1491 }
1492 
1493 static inline bool sched_core_disabled(void)
1494 {
1495 	return true;
1496 }
1497 
1498 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1499 {
1500 	return &rq->__lock;
1501 }
1502 
1503 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1504 {
1505 	return &rq->__lock;
1506 }
1507 
1508 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1509 {
1510 	return true;
1511 }
1512 
1513 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1514 {
1515 	return true;
1516 }
1517 
1518 static inline bool sched_group_cookie_match(struct rq *rq,
1519 					    struct task_struct *p,
1520 					    struct sched_group *group)
1521 {
1522 	return true;
1523 }
1524 
1525 #endif /* !CONFIG_SCHED_CORE */
1526 
1527 #ifdef CONFIG_RT_GROUP_SCHED
1528 # ifdef CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED
1529 DECLARE_STATIC_KEY_FALSE(rt_group_sched);
1530 static inline bool rt_group_sched_enabled(void)
1531 {
1532 	return static_branch_unlikely(&rt_group_sched);
1533 }
1534 # else /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED: */
1535 DECLARE_STATIC_KEY_TRUE(rt_group_sched);
1536 static inline bool rt_group_sched_enabled(void)
1537 {
1538 	return static_branch_likely(&rt_group_sched);
1539 }
1540 # endif /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED */
1541 #else /* !CONFIG_RT_GROUP_SCHED: */
1542 # define rt_group_sched_enabled()	false
1543 #endif /* !CONFIG_RT_GROUP_SCHED */
1544 
1545 static inline void lockdep_assert_rq_held(struct rq *rq)
1546 {
1547 	lockdep_assert_held(__rq_lockp(rq));
1548 }
1549 
1550 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass);
1551 extern bool raw_spin_rq_trylock(struct rq *rq);
1552 extern void raw_spin_rq_unlock(struct rq *rq);
1553 
1554 static inline void raw_spin_rq_lock(struct rq *rq)
1555 {
1556 	raw_spin_rq_lock_nested(rq, 0);
1557 }
1558 
1559 static inline void raw_spin_rq_lock_irq(struct rq *rq)
1560 {
1561 	local_irq_disable();
1562 	raw_spin_rq_lock(rq);
1563 }
1564 
1565 static inline void raw_spin_rq_unlock_irq(struct rq *rq)
1566 {
1567 	raw_spin_rq_unlock(rq);
1568 	local_irq_enable();
1569 }
1570 
1571 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq)
1572 {
1573 	unsigned long flags;
1574 
1575 	local_irq_save(flags);
1576 	raw_spin_rq_lock(rq);
1577 
1578 	return flags;
1579 }
1580 
1581 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags)
1582 {
1583 	raw_spin_rq_unlock(rq);
1584 	local_irq_restore(flags);
1585 }
1586 
1587 #define raw_spin_rq_lock_irqsave(rq, flags)	\
1588 do {						\
1589 	flags = _raw_spin_rq_lock_irqsave(rq);	\
1590 } while (0)
1591 
1592 #ifdef CONFIG_SCHED_SMT
1593 extern void __update_idle_core(struct rq *rq);
1594 
1595 static inline void update_idle_core(struct rq *rq)
1596 {
1597 	if (static_branch_unlikely(&sched_smt_present))
1598 		__update_idle_core(rq);
1599 }
1600 
1601 #else /* !CONFIG_SCHED_SMT: */
1602 static inline void update_idle_core(struct rq *rq) { }
1603 #endif /* !CONFIG_SCHED_SMT */
1604 
1605 #ifdef CONFIG_FAIR_GROUP_SCHED
1606 
1607 static inline struct task_struct *task_of(struct sched_entity *se)
1608 {
1609 	WARN_ON_ONCE(!entity_is_task(se));
1610 	return container_of(se, struct task_struct, se);
1611 }
1612 
1613 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1614 {
1615 	return p->se.cfs_rq;
1616 }
1617 
1618 /* runqueue on which this entity is (to be) queued */
1619 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1620 {
1621 	return se->cfs_rq;
1622 }
1623 
1624 /* runqueue "owned" by this group */
1625 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1626 {
1627 	return grp->my_q;
1628 }
1629 
1630 #else /* !CONFIG_FAIR_GROUP_SCHED: */
1631 
1632 #define task_of(_se)		container_of(_se, struct task_struct, se)
1633 
1634 static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p)
1635 {
1636 	return &task_rq(p)->cfs;
1637 }
1638 
1639 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1640 {
1641 	const struct task_struct *p = task_of(se);
1642 	struct rq *rq = task_rq(p);
1643 
1644 	return &rq->cfs;
1645 }
1646 
1647 /* runqueue "owned" by this group */
1648 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1649 {
1650 	return NULL;
1651 }
1652 
1653 #endif /* !CONFIG_FAIR_GROUP_SCHED */
1654 
1655 extern void update_rq_clock(struct rq *rq);
1656 
1657 /*
1658  * rq::clock_update_flags bits
1659  *
1660  * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1661  *  call to __schedule(). This is an optimisation to avoid
1662  *  neighbouring rq clock updates.
1663  *
1664  * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1665  *  in effect and calls to update_rq_clock() are being ignored.
1666  *
1667  * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1668  *  made to update_rq_clock() since the last time rq::lock was pinned.
1669  *
1670  * If inside of __schedule(), clock_update_flags will have been
1671  * shifted left (a left shift is a cheap operation for the fast path
1672  * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1673  *
1674  *	if (rq-clock_update_flags >= RQCF_UPDATED)
1675  *
1676  * to check if %RQCF_UPDATED is set. It'll never be shifted more than
1677  * one position though, because the next rq_unpin_lock() will shift it
1678  * back.
1679  */
1680 #define RQCF_REQ_SKIP		0x01
1681 #define RQCF_ACT_SKIP		0x02
1682 #define RQCF_UPDATED		0x04
1683 
1684 static inline void assert_clock_updated(struct rq *rq)
1685 {
1686 	/*
1687 	 * The only reason for not seeing a clock update since the
1688 	 * last rq_pin_lock() is if we're currently skipping updates.
1689 	 */
1690 	WARN_ON_ONCE(rq->clock_update_flags < RQCF_ACT_SKIP);
1691 }
1692 
1693 static inline u64 rq_clock(struct rq *rq)
1694 {
1695 	lockdep_assert_rq_held(rq);
1696 	assert_clock_updated(rq);
1697 
1698 	return rq->clock;
1699 }
1700 
1701 static inline u64 rq_clock_task(struct rq *rq)
1702 {
1703 	lockdep_assert_rq_held(rq);
1704 	assert_clock_updated(rq);
1705 
1706 	return rq->clock_task;
1707 }
1708 
1709 static inline void rq_clock_skip_update(struct rq *rq)
1710 {
1711 	lockdep_assert_rq_held(rq);
1712 	rq->clock_update_flags |= RQCF_REQ_SKIP;
1713 }
1714 
1715 /*
1716  * See rt task throttling, which is the only time a skip
1717  * request is canceled.
1718  */
1719 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1720 {
1721 	lockdep_assert_rq_held(rq);
1722 	rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1723 }
1724 
1725 /*
1726  * During cpu offlining and rq wide unthrottling, we can trigger
1727  * an update_rq_clock() for several cfs and rt runqueues (Typically
1728  * when using list_for_each_entry_*)
1729  * rq_clock_start_loop_update() can be called after updating the clock
1730  * once and before iterating over the list to prevent multiple update.
1731  * After the iterative traversal, we need to call rq_clock_stop_loop_update()
1732  * to clear RQCF_ACT_SKIP of rq->clock_update_flags.
1733  */
1734 static inline void rq_clock_start_loop_update(struct rq *rq)
1735 {
1736 	lockdep_assert_rq_held(rq);
1737 	WARN_ON_ONCE(rq->clock_update_flags & RQCF_ACT_SKIP);
1738 	rq->clock_update_flags |= RQCF_ACT_SKIP;
1739 }
1740 
1741 static inline void rq_clock_stop_loop_update(struct rq *rq)
1742 {
1743 	lockdep_assert_rq_held(rq);
1744 	rq->clock_update_flags &= ~RQCF_ACT_SKIP;
1745 }
1746 
1747 struct rq_flags {
1748 	unsigned long flags;
1749 	struct pin_cookie cookie;
1750 	/*
1751 	 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1752 	 * current pin context is stashed here in case it needs to be
1753 	 * restored in rq_repin_lock().
1754 	 */
1755 	unsigned int clock_update_flags;
1756 };
1757 
1758 extern struct balance_callback balance_push_callback;
1759 
1760 #ifdef CONFIG_SCHED_CLASS_EXT
1761 extern const struct sched_class ext_sched_class;
1762 
1763 DECLARE_STATIC_KEY_FALSE(__scx_enabled);	/* SCX BPF scheduler loaded */
1764 DECLARE_STATIC_KEY_FALSE(__scx_switched_all);	/* all fair class tasks on SCX */
1765 
1766 #define scx_enabled()		static_branch_unlikely(&__scx_enabled)
1767 #define scx_switched_all()	static_branch_unlikely(&__scx_switched_all)
1768 
1769 static inline void scx_rq_clock_update(struct rq *rq, u64 clock)
1770 {
1771 	if (!scx_enabled())
1772 		return;
1773 	WRITE_ONCE(rq->scx.clock, clock);
1774 	smp_store_release(&rq->scx.flags, rq->scx.flags | SCX_RQ_CLK_VALID);
1775 }
1776 
1777 static inline void scx_rq_clock_invalidate(struct rq *rq)
1778 {
1779 	if (!scx_enabled())
1780 		return;
1781 	WRITE_ONCE(rq->scx.flags, rq->scx.flags & ~SCX_RQ_CLK_VALID);
1782 }
1783 
1784 #else /* !CONFIG_SCHED_CLASS_EXT: */
1785 #define scx_enabled()		false
1786 #define scx_switched_all()	false
1787 
1788 static inline void scx_rq_clock_update(struct rq *rq, u64 clock) {}
1789 static inline void scx_rq_clock_invalidate(struct rq *rq) {}
1790 #endif /* !CONFIG_SCHED_CLASS_EXT */
1791 
1792 /*
1793  * Lockdep annotation that avoids accidental unlocks; it's like a
1794  * sticky/continuous lockdep_assert_held().
1795  *
1796  * This avoids code that has access to 'struct rq *rq' (basically everything in
1797  * the scheduler) from accidentally unlocking the rq if they do not also have a
1798  * copy of the (on-stack) 'struct rq_flags rf'.
1799  *
1800  * Also see Documentation/locking/lockdep-design.rst.
1801  */
1802 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1803 {
1804 	rf->cookie = lockdep_pin_lock(__rq_lockp(rq));
1805 
1806 	rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1807 	rf->clock_update_flags = 0;
1808 	WARN_ON_ONCE(rq->balance_callback && rq->balance_callback != &balance_push_callback);
1809 }
1810 
1811 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1812 {
1813 	if (rq->clock_update_flags > RQCF_ACT_SKIP)
1814 		rf->clock_update_flags = RQCF_UPDATED;
1815 
1816 	scx_rq_clock_invalidate(rq);
1817 	lockdep_unpin_lock(__rq_lockp(rq), rf->cookie);
1818 }
1819 
1820 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1821 {
1822 	lockdep_repin_lock(__rq_lockp(rq), rf->cookie);
1823 
1824 	/*
1825 	 * Restore the value we stashed in @rf for this pin context.
1826 	 */
1827 	rq->clock_update_flags |= rf->clock_update_flags;
1828 }
1829 
1830 extern
1831 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1832 	__acquires(rq->lock);
1833 
1834 extern
1835 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1836 	__acquires(p->pi_lock)
1837 	__acquires(rq->lock);
1838 
1839 static inline void
1840 __task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1841 	__releases(rq->lock)
1842 {
1843 	rq_unpin_lock(rq, rf);
1844 	raw_spin_rq_unlock(rq);
1845 }
1846 
1847 static inline void
1848 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1849 	__releases(rq->lock)
1850 	__releases(p->pi_lock)
1851 {
1852 	__task_rq_unlock(rq, p, rf);
1853 	raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1854 }
1855 
1856 DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct,
1857 		    _T->rq = task_rq_lock(_T->lock, &_T->rf),
1858 		    task_rq_unlock(_T->rq, _T->lock, &_T->rf),
1859 		    struct rq *rq; struct rq_flags rf)
1860 
1861 DEFINE_LOCK_GUARD_1(__task_rq_lock, struct task_struct,
1862 		    _T->rq = __task_rq_lock(_T->lock, &_T->rf),
1863 		    __task_rq_unlock(_T->rq, _T->lock, &_T->rf),
1864 		    struct rq *rq; struct rq_flags rf)
1865 
1866 static inline void rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1867 	__acquires(rq->lock)
1868 {
1869 	raw_spin_rq_lock_irqsave(rq, rf->flags);
1870 	rq_pin_lock(rq, rf);
1871 }
1872 
1873 static inline void rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1874 	__acquires(rq->lock)
1875 {
1876 	raw_spin_rq_lock_irq(rq);
1877 	rq_pin_lock(rq, rf);
1878 }
1879 
1880 static inline void rq_lock(struct rq *rq, struct rq_flags *rf)
1881 	__acquires(rq->lock)
1882 {
1883 	raw_spin_rq_lock(rq);
1884 	rq_pin_lock(rq, rf);
1885 }
1886 
1887 static inline void rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1888 	__releases(rq->lock)
1889 {
1890 	rq_unpin_lock(rq, rf);
1891 	raw_spin_rq_unlock_irqrestore(rq, rf->flags);
1892 }
1893 
1894 static inline void rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1895 	__releases(rq->lock)
1896 {
1897 	rq_unpin_lock(rq, rf);
1898 	raw_spin_rq_unlock_irq(rq);
1899 }
1900 
1901 static inline void rq_unlock(struct rq *rq, struct rq_flags *rf)
1902 	__releases(rq->lock)
1903 {
1904 	rq_unpin_lock(rq, rf);
1905 	raw_spin_rq_unlock(rq);
1906 }
1907 
1908 DEFINE_LOCK_GUARD_1(rq_lock, struct rq,
1909 		    rq_lock(_T->lock, &_T->rf),
1910 		    rq_unlock(_T->lock, &_T->rf),
1911 		    struct rq_flags rf)
1912 
1913 DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq,
1914 		    rq_lock_irq(_T->lock, &_T->rf),
1915 		    rq_unlock_irq(_T->lock, &_T->rf),
1916 		    struct rq_flags rf)
1917 
1918 DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq,
1919 		    rq_lock_irqsave(_T->lock, &_T->rf),
1920 		    rq_unlock_irqrestore(_T->lock, &_T->rf),
1921 		    struct rq_flags rf)
1922 
1923 static inline struct rq *this_rq_lock_irq(struct rq_flags *rf)
1924 	__acquires(rq->lock)
1925 {
1926 	struct rq *rq;
1927 
1928 	local_irq_disable();
1929 	rq = this_rq();
1930 	rq_lock(rq, rf);
1931 
1932 	return rq;
1933 }
1934 
1935 #ifdef CONFIG_NUMA
1936 
1937 enum numa_topology_type {
1938 	NUMA_DIRECT,
1939 	NUMA_GLUELESS_MESH,
1940 	NUMA_BACKPLANE,
1941 };
1942 
1943 extern enum numa_topology_type sched_numa_topology_type;
1944 extern int sched_max_numa_distance;
1945 extern bool find_numa_distance(int distance);
1946 extern void sched_init_numa(int offline_node);
1947 extern void sched_update_numa(int cpu, bool online);
1948 extern void sched_domains_numa_masks_set(unsigned int cpu);
1949 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1950 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1951 
1952 #else /* !CONFIG_NUMA: */
1953 
1954 static inline void sched_init_numa(int offline_node) { }
1955 static inline void sched_update_numa(int cpu, bool online) { }
1956 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
1957 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1958 
1959 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1960 {
1961 	return nr_cpu_ids;
1962 }
1963 
1964 #endif /* !CONFIG_NUMA */
1965 
1966 #ifdef CONFIG_NUMA_BALANCING
1967 
1968 /* The regions in numa_faults array from task_struct */
1969 enum numa_faults_stats {
1970 	NUMA_MEM = 0,
1971 	NUMA_CPU,
1972 	NUMA_MEMBUF,
1973 	NUMA_CPUBUF
1974 };
1975 
1976 extern void sched_setnuma(struct task_struct *p, int node);
1977 extern int migrate_task_to(struct task_struct *p, int cpu);
1978 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1979 			int cpu, int scpu);
1980 extern void init_numa_balancing(u64 clone_flags, struct task_struct *p);
1981 
1982 #else /* !CONFIG_NUMA_BALANCING: */
1983 
1984 static inline void
1985 init_numa_balancing(u64 clone_flags, struct task_struct *p)
1986 {
1987 }
1988 
1989 #endif /* !CONFIG_NUMA_BALANCING */
1990 
1991 static inline void
1992 queue_balance_callback(struct rq *rq,
1993 		       struct balance_callback *head,
1994 		       void (*func)(struct rq *rq))
1995 {
1996 	lockdep_assert_rq_held(rq);
1997 
1998 	/*
1999 	 * Don't (re)queue an already queued item; nor queue anything when
2000 	 * balance_push() is active, see the comment with
2001 	 * balance_push_callback.
2002 	 */
2003 	if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
2004 		return;
2005 
2006 	head->func = func;
2007 	head->next = rq->balance_callback;
2008 	rq->balance_callback = head;
2009 }
2010 
2011 #define rcu_dereference_check_sched_domain(p) \
2012 	rcu_dereference_check((p), lockdep_is_held(&sched_domains_mutex))
2013 
2014 /*
2015  * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
2016  * See destroy_sched_domains: call_rcu for details.
2017  *
2018  * The domain tree of any CPU may only be accessed from within
2019  * preempt-disabled sections.
2020  */
2021 #define for_each_domain(cpu, __sd) \
2022 	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
2023 			__sd; __sd = __sd->parent)
2024 
2025 /* A mask of all the SD flags that have the SDF_SHARED_CHILD metaflag */
2026 #define SD_FLAG(name, mflags) (name * !!((mflags) & SDF_SHARED_CHILD)) |
2027 static const unsigned int SD_SHARED_CHILD_MASK =
2028 #include <linux/sched/sd_flags.h>
2029 0;
2030 #undef SD_FLAG
2031 
2032 /**
2033  * highest_flag_domain - Return highest sched_domain containing flag.
2034  * @cpu:	The CPU whose highest level of sched domain is to
2035  *		be returned.
2036  * @flag:	The flag to check for the highest sched_domain
2037  *		for the given CPU.
2038  *
2039  * Returns the highest sched_domain of a CPU which contains @flag. If @flag has
2040  * the SDF_SHARED_CHILD metaflag, all the children domains also have @flag.
2041  */
2042 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
2043 {
2044 	struct sched_domain *sd, *hsd = NULL;
2045 
2046 	for_each_domain(cpu, sd) {
2047 		if (sd->flags & flag) {
2048 			hsd = sd;
2049 			continue;
2050 		}
2051 
2052 		/*
2053 		 * Stop the search if @flag is known to be shared at lower
2054 		 * levels. It will not be found further up.
2055 		 */
2056 		if (flag & SD_SHARED_CHILD_MASK)
2057 			break;
2058 	}
2059 
2060 	return hsd;
2061 }
2062 
2063 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
2064 {
2065 	struct sched_domain *sd;
2066 
2067 	for_each_domain(cpu, sd) {
2068 		if (sd->flags & flag)
2069 			break;
2070 	}
2071 
2072 	return sd;
2073 }
2074 
2075 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
2076 DECLARE_PER_CPU(int, sd_llc_size);
2077 DECLARE_PER_CPU(int, sd_llc_id);
2078 DECLARE_PER_CPU(int, sd_share_id);
2079 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
2080 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
2081 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
2082 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
2083 
2084 extern struct static_key_false sched_asym_cpucapacity;
2085 extern struct static_key_false sched_cluster_active;
2086 
2087 static __always_inline bool sched_asym_cpucap_active(void)
2088 {
2089 	return static_branch_unlikely(&sched_asym_cpucapacity);
2090 }
2091 
2092 struct sched_group_capacity {
2093 	atomic_t		ref;
2094 	/*
2095 	 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
2096 	 * for a single CPU.
2097 	 */
2098 	unsigned long		capacity;
2099 	unsigned long		min_capacity;		/* Min per-CPU capacity in group */
2100 	unsigned long		max_capacity;		/* Max per-CPU capacity in group */
2101 	unsigned long		next_update;
2102 	int			imbalance;		/* XXX unrelated to capacity but shared group state */
2103 
2104 	int			id;
2105 
2106 	unsigned long		cpumask[];		/* Balance mask */
2107 };
2108 
2109 struct sched_group {
2110 	struct sched_group	*next;			/* Must be a circular list */
2111 	atomic_t		ref;
2112 
2113 	unsigned int		group_weight;
2114 	unsigned int		cores;
2115 	struct sched_group_capacity *sgc;
2116 	int			asym_prefer_cpu;	/* CPU of highest priority in group */
2117 	int			flags;
2118 
2119 	/*
2120 	 * The CPUs this group covers.
2121 	 *
2122 	 * NOTE: this field is variable length. (Allocated dynamically
2123 	 * by attaching extra space to the end of the structure,
2124 	 * depending on how many CPUs the kernel has booted up with)
2125 	 */
2126 	unsigned long		cpumask[];
2127 };
2128 
2129 static inline struct cpumask *sched_group_span(struct sched_group *sg)
2130 {
2131 	return to_cpumask(sg->cpumask);
2132 }
2133 
2134 /*
2135  * See build_balance_mask().
2136  */
2137 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
2138 {
2139 	return to_cpumask(sg->sgc->cpumask);
2140 }
2141 
2142 extern int group_balance_cpu(struct sched_group *sg);
2143 
2144 extern void update_sched_domain_debugfs(void);
2145 extern void dirty_sched_domain_sysctl(int cpu);
2146 
2147 extern int sched_update_scaling(void);
2148 
2149 static inline const struct cpumask *task_user_cpus(struct task_struct *p)
2150 {
2151 	if (!p->user_cpus_ptr)
2152 		return cpu_possible_mask; /* &init_task.cpus_mask */
2153 	return p->user_cpus_ptr;
2154 }
2155 
2156 #ifdef CONFIG_CGROUP_SCHED
2157 
2158 /*
2159  * Return the group to which this tasks belongs.
2160  *
2161  * We cannot use task_css() and friends because the cgroup subsystem
2162  * changes that value before the cgroup_subsys::attach() method is called,
2163  * therefore we cannot pin it and might observe the wrong value.
2164  *
2165  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
2166  * core changes this before calling sched_move_task().
2167  *
2168  * Instead we use a 'copy' which is updated from sched_move_task() while
2169  * holding both task_struct::pi_lock and rq::lock.
2170  */
2171 static inline struct task_group *task_group(struct task_struct *p)
2172 {
2173 	return p->sched_task_group;
2174 }
2175 
2176 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
2177 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
2178 {
2179 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
2180 	struct task_group *tg = task_group(p);
2181 #endif
2182 
2183 #ifdef CONFIG_FAIR_GROUP_SCHED
2184 	set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
2185 	p->se.cfs_rq = tg->cfs_rq[cpu];
2186 	p->se.parent = tg->se[cpu];
2187 	p->se.depth = tg->se[cpu] ? tg->se[cpu]->depth + 1 : 0;
2188 #endif
2189 
2190 #ifdef CONFIG_RT_GROUP_SCHED
2191 	/*
2192 	 * p->rt.rt_rq is NULL initially and it is easier to assign
2193 	 * root_task_group's rt_rq than switching in rt_rq_of_se()
2194 	 * Clobbers tg(!)
2195 	 */
2196 	if (!rt_group_sched_enabled())
2197 		tg = &root_task_group;
2198 	p->rt.rt_rq  = tg->rt_rq[cpu];
2199 	p->rt.parent = tg->rt_se[cpu];
2200 #endif /* CONFIG_RT_GROUP_SCHED */
2201 }
2202 
2203 #else /* !CONFIG_CGROUP_SCHED: */
2204 
2205 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
2206 
2207 static inline struct task_group *task_group(struct task_struct *p)
2208 {
2209 	return NULL;
2210 }
2211 
2212 #endif /* !CONFIG_CGROUP_SCHED */
2213 
2214 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
2215 {
2216 	set_task_rq(p, cpu);
2217 #ifdef CONFIG_SMP
2218 	/*
2219 	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
2220 	 * successfully executed on another CPU. We must ensure that updates of
2221 	 * per-task data have been completed by this moment.
2222 	 */
2223 	smp_wmb();
2224 	WRITE_ONCE(task_thread_info(p)->cpu, cpu);
2225 	p->wake_cpu = cpu;
2226 	rseq_sched_set_ids_changed(p);
2227 #endif /* CONFIG_SMP */
2228 }
2229 
2230 /*
2231  * Tunables:
2232  */
2233 
2234 #define SCHED_FEAT(name, enabled)	\
2235 	__SCHED_FEAT_##name ,
2236 
2237 enum {
2238 #include "features.h"
2239 	__SCHED_FEAT_NR,
2240 };
2241 
2242 #undef SCHED_FEAT
2243 
2244 /*
2245  * To support run-time toggling of sched features, all the translation units
2246  * (but core.c) reference the sysctl_sched_features defined in core.c.
2247  */
2248 extern __read_mostly unsigned int sysctl_sched_features;
2249 
2250 #ifdef CONFIG_JUMP_LABEL
2251 
2252 #define SCHED_FEAT(name, enabled)					\
2253 static __always_inline bool static_branch_##name(struct static_key *key) \
2254 {									\
2255 	return static_key_##enabled(key);				\
2256 }
2257 
2258 #include "features.h"
2259 #undef SCHED_FEAT
2260 
2261 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
2262 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
2263 
2264 #else /* !CONFIG_JUMP_LABEL: */
2265 
2266 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2267 
2268 #endif /* !CONFIG_JUMP_LABEL */
2269 
2270 extern struct static_key_false sched_numa_balancing;
2271 extern struct static_key_false sched_schedstats;
2272 
2273 static inline u64 global_rt_period(void)
2274 {
2275 	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
2276 }
2277 
2278 static inline u64 global_rt_runtime(void)
2279 {
2280 	if (sysctl_sched_rt_runtime < 0)
2281 		return RUNTIME_INF;
2282 
2283 	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
2284 }
2285 
2286 /*
2287  * Is p the current execution context?
2288  */
2289 static inline int task_current(struct rq *rq, struct task_struct *p)
2290 {
2291 	return rq->curr == p;
2292 }
2293 
2294 /*
2295  * Is p the current scheduling context?
2296  *
2297  * Note that it might be the current execution context at the same time if
2298  * rq->curr == rq->donor == p.
2299  */
2300 static inline int task_current_donor(struct rq *rq, struct task_struct *p)
2301 {
2302 	return rq->donor == p;
2303 }
2304 
2305 static inline bool task_is_blocked(struct task_struct *p)
2306 {
2307 	if (!sched_proxy_exec())
2308 		return false;
2309 
2310 	return !!p->blocked_on;
2311 }
2312 
2313 static inline int task_on_cpu(struct rq *rq, struct task_struct *p)
2314 {
2315 	return p->on_cpu;
2316 }
2317 
2318 static inline int task_on_rq_queued(struct task_struct *p)
2319 {
2320 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_QUEUED;
2321 }
2322 
2323 static inline int task_on_rq_migrating(struct task_struct *p)
2324 {
2325 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
2326 }
2327 
2328 /* Wake flags. The first three directly map to some SD flag value */
2329 #define WF_EXEC			0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
2330 #define WF_FORK			0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
2331 #define WF_TTWU			0x08 /* Wakeup;            maps to SD_BALANCE_WAKE */
2332 
2333 #define WF_SYNC			0x10 /* Waker goes to sleep after wakeup */
2334 #define WF_MIGRATED		0x20 /* Internal use, task got migrated */
2335 #define WF_CURRENT_CPU		0x40 /* Prefer to move the wakee to the current CPU. */
2336 #define WF_RQ_SELECTED		0x80 /* ->select_task_rq() was called */
2337 
2338 static_assert(WF_EXEC == SD_BALANCE_EXEC);
2339 static_assert(WF_FORK == SD_BALANCE_FORK);
2340 static_assert(WF_TTWU == SD_BALANCE_WAKE);
2341 
2342 /*
2343  * To aid in avoiding the subversion of "niceness" due to uneven distribution
2344  * of tasks with abnormal "nice" values across CPUs the contribution that
2345  * each task makes to its run queue's load is weighted according to its
2346  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
2347  * scaled version of the new time slice allocation that they receive on time
2348  * slice expiry etc.
2349  */
2350 
2351 #define WEIGHT_IDLEPRIO		3
2352 #define WMULT_IDLEPRIO		1431655765
2353 
2354 extern const int		sched_prio_to_weight[40];
2355 extern const u32		sched_prio_to_wmult[40];
2356 
2357 /*
2358  * {de,en}queue flags:
2359  *
2360  * SLEEP/WAKEUP - task is no-longer/just-became runnable
2361  *
2362  * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
2363  *                are in a known state which allows modification. Such pairs
2364  *                should preserve as much state as possible.
2365  *
2366  * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
2367  *        in the runqueue.
2368  *
2369  * NOCLOCK - skip the update_rq_clock() (avoids double updates)
2370  *
2371  * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE)
2372  *
2373  * DELAYED - de/re-queue a sched_delayed task
2374  *
2375  * CLASS - going to update p->sched_class; makes sched_change call the
2376  *         various switch methods.
2377  *
2378  * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
2379  * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
2380  * ENQUEUE_MIGRATED  - the task was migrated during wakeup
2381  * ENQUEUE_RQ_SELECTED - ->select_task_rq() was called
2382  *
2383  * XXX SAVE/RESTORE in combination with CLASS doesn't really make sense, but
2384  * SCHED_DEADLINE seems to rely on this for now.
2385  */
2386 
2387 #define DEQUEUE_SLEEP		0x0001 /* Matches ENQUEUE_WAKEUP */
2388 #define DEQUEUE_SAVE		0x0002 /* Matches ENQUEUE_RESTORE */
2389 #define DEQUEUE_MOVE		0x0004 /* Matches ENQUEUE_MOVE */
2390 #define DEQUEUE_NOCLOCK		0x0008 /* Matches ENQUEUE_NOCLOCK */
2391 
2392 #define DEQUEUE_MIGRATING	0x0010 /* Matches ENQUEUE_MIGRATING */
2393 #define DEQUEUE_DELAYED		0x0020 /* Matches ENQUEUE_DELAYED */
2394 #define DEQUEUE_CLASS		0x0040 /* Matches ENQUEUE_CLASS */
2395 
2396 #define DEQUEUE_SPECIAL		0x00010000
2397 #define DEQUEUE_THROTTLE	0x00020000
2398 
2399 #define ENQUEUE_WAKEUP		0x0001
2400 #define ENQUEUE_RESTORE		0x0002
2401 #define ENQUEUE_MOVE		0x0004
2402 #define ENQUEUE_NOCLOCK		0x0008
2403 
2404 #define ENQUEUE_MIGRATING	0x0010
2405 #define ENQUEUE_DELAYED		0x0020
2406 #define ENQUEUE_CLASS		0x0040
2407 
2408 #define ENQUEUE_HEAD		0x00010000
2409 #define ENQUEUE_REPLENISH	0x00020000
2410 #define ENQUEUE_MIGRATED	0x00040000
2411 #define ENQUEUE_INITIAL		0x00080000
2412 #define ENQUEUE_RQ_SELECTED	0x00100000
2413 
2414 #define RETRY_TASK		((void *)-1UL)
2415 
2416 struct affinity_context {
2417 	const struct cpumask	*new_mask;
2418 	struct cpumask		*user_mask;
2419 	unsigned int		flags;
2420 };
2421 
2422 extern s64 update_curr_common(struct rq *rq);
2423 
2424 struct sched_class {
2425 
2426 #ifdef CONFIG_UCLAMP_TASK
2427 	int uclamp_enabled;
2428 #endif
2429 	/*
2430 	 * idle:  0
2431 	 * ext:   1
2432 	 * fair:  2
2433 	 * rt:    4
2434 	 * dl:    8
2435 	 * stop: 16
2436 	 */
2437 	unsigned int queue_mask;
2438 
2439 	/*
2440 	 * move_queued_task/activate_task/enqueue_task: rq->lock
2441 	 * ttwu_do_activate/activate_task/enqueue_task: rq->lock
2442 	 * wake_up_new_task/activate_task/enqueue_task: task_rq_lock
2443 	 * ttwu_runnable/enqueue_task: task_rq_lock
2444 	 * proxy_task_current: rq->lock
2445 	 * sched_change_end
2446 	 */
2447 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
2448 	/*
2449 	 * move_queued_task/deactivate_task/dequeue_task: rq->lock
2450 	 * __schedule/block_task/dequeue_task: rq->lock
2451 	 * proxy_task_current: rq->lock
2452 	 * wait_task_inactive: task_rq_lock
2453 	 * sched_change_begin
2454 	 */
2455 	bool (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
2456 
2457 	/*
2458 	 * do_sched_yield: rq->lock
2459 	 */
2460 	void (*yield_task)   (struct rq *rq);
2461 	/*
2462 	 * yield_to: rq->lock (double)
2463 	 */
2464 	bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
2465 
2466 	/*
2467 	 * move_queued_task: rq->lock
2468 	 * __migrate_swap_task: rq->lock
2469 	 * ttwu_do_activate: rq->lock
2470 	 * ttwu_runnable: task_rq_lock
2471 	 * wake_up_new_task: task_rq_lock
2472 	 */
2473 	void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags);
2474 
2475 	/*
2476 	 * schedule/pick_next_task/prev_balance: rq->lock
2477 	 */
2478 	int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2479 
2480 	/*
2481 	 * schedule/pick_next_task: rq->lock
2482 	 */
2483 	struct task_struct *(*pick_task)(struct rq *rq, struct rq_flags *rf);
2484 	/*
2485 	 * Optional! When implemented pick_next_task() should be equivalent to:
2486 	 *
2487 	 *   next = pick_task();
2488 	 *   if (next) {
2489 	 *       put_prev_task(prev);
2490 	 *       set_next_task_first(next);
2491 	 *   }
2492 	 */
2493 	struct task_struct *(*pick_next_task)(struct rq *rq, struct task_struct *prev,
2494 					      struct rq_flags *rf);
2495 
2496 	/*
2497 	 * sched_change:
2498 	 * __schedule: rq->lock
2499 	 */
2500 	void (*put_prev_task)(struct rq *rq, struct task_struct *p, struct task_struct *next);
2501 	void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
2502 
2503 	/*
2504 	 * select_task_rq: p->pi_lock
2505 	 * sched_exec: p->pi_lock
2506 	 */
2507 	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
2508 
2509 	/*
2510 	 * set_task_cpu: p->pi_lock || rq->lock (ttwu like)
2511 	 */
2512 	void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
2513 
2514 	/*
2515 	 * ttwu_do_activate: rq->lock
2516 	 * wake_up_new_task: task_rq_lock
2517 	 */
2518 	void (*task_woken)(struct rq *this_rq, struct task_struct *task);
2519 
2520 	/*
2521 	 * do_set_cpus_allowed: task_rq_lock + sched_change
2522 	 */
2523 	void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx);
2524 
2525 	/*
2526 	 * sched_set_rq_{on,off}line: rq->lock
2527 	 */
2528 	void (*rq_online)(struct rq *rq);
2529 	void (*rq_offline)(struct rq *rq);
2530 
2531 	/*
2532 	 * push_cpu_stop: p->pi_lock && rq->lock
2533 	 */
2534 	struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
2535 
2536 	/*
2537 	 * hrtick: rq->lock
2538 	 * sched_tick: rq->lock
2539 	 * sched_tick_remote: rq->lock
2540 	 */
2541 	void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
2542 	/*
2543 	 * sched_cgroup_fork: p->pi_lock
2544 	 */
2545 	void (*task_fork)(struct task_struct *p);
2546 	/*
2547 	 * finish_task_switch: no locks
2548 	 */
2549 	void (*task_dead)(struct task_struct *p);
2550 
2551 	/*
2552 	 * sched_change
2553 	 */
2554 	void (*switching_from)(struct rq *this_rq, struct task_struct *task);
2555 	void (*switched_from) (struct rq *this_rq, struct task_struct *task);
2556 	void (*switching_to)  (struct rq *this_rq, struct task_struct *task);
2557 	void (*switched_to)   (struct rq *this_rq, struct task_struct *task);
2558 	u64  (*get_prio)     (struct rq *this_rq, struct task_struct *task);
2559 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
2560 			      u64 oldprio);
2561 
2562 	/*
2563 	 * set_load_weight: task_rq_lock + sched_change
2564 	 * __setscheduler_parms: task_rq_lock + sched_change
2565 	 */
2566 	void (*reweight_task)(struct rq *this_rq, struct task_struct *task,
2567 			      const struct load_weight *lw);
2568 
2569 	/*
2570 	 * sched_rr_get_interval: task_rq_lock
2571 	 */
2572 	unsigned int (*get_rr_interval)(struct rq *rq,
2573 					struct task_struct *task);
2574 
2575 	/*
2576 	 * task_sched_runtime: task_rq_lock
2577 	 */
2578 	void (*update_curr)(struct rq *rq);
2579 
2580 #ifdef CONFIG_FAIR_GROUP_SCHED
2581 	/*
2582 	 * sched_change_group: task_rq_lock + sched_change
2583 	 */
2584 	void (*task_change_group)(struct task_struct *p);
2585 #endif
2586 
2587 #ifdef CONFIG_SCHED_CORE
2588 	/*
2589 	 * pick_next_task: rq->lock
2590 	 * try_steal_cookie: rq->lock (double)
2591 	 */
2592 	int (*task_is_throttled)(struct task_struct *p, int cpu);
2593 #endif
2594 };
2595 
2596 /*
2597  * Does not nest; only used around sched_class::pick_task() rq-lock-breaks.
2598  */
2599 static inline void rq_modified_clear(struct rq *rq)
2600 {
2601 	rq->queue_mask = 0;
2602 }
2603 
2604 static inline bool rq_modified_above(struct rq *rq, const struct sched_class * class)
2605 {
2606 	unsigned int mask = class->queue_mask;
2607 	return rq->queue_mask & ~((mask << 1) - 1);
2608 }
2609 
2610 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
2611 {
2612 	WARN_ON_ONCE(rq->donor != prev);
2613 	prev->sched_class->put_prev_task(rq, prev, NULL);
2614 }
2615 
2616 static inline void set_next_task(struct rq *rq, struct task_struct *next)
2617 {
2618 	next->sched_class->set_next_task(rq, next, false);
2619 }
2620 
2621 static inline void
2622 __put_prev_set_next_dl_server(struct rq *rq,
2623 			      struct task_struct *prev,
2624 			      struct task_struct *next)
2625 {
2626 	prev->dl_server = NULL;
2627 	next->dl_server = rq->dl_server;
2628 	rq->dl_server = NULL;
2629 }
2630 
2631 static inline void put_prev_set_next_task(struct rq *rq,
2632 					  struct task_struct *prev,
2633 					  struct task_struct *next)
2634 {
2635 	WARN_ON_ONCE(rq->donor != prev);
2636 
2637 	__put_prev_set_next_dl_server(rq, prev, next);
2638 
2639 	if (next == prev)
2640 		return;
2641 
2642 	prev->sched_class->put_prev_task(rq, prev, next);
2643 	next->sched_class->set_next_task(rq, next, true);
2644 }
2645 
2646 /*
2647  * Helper to define a sched_class instance; each one is placed in a separate
2648  * section which is ordered by the linker script:
2649  *
2650  *   include/asm-generic/vmlinux.lds.h
2651  *
2652  * *CAREFUL* they are laid out in *REVERSE* order!!!
2653  *
2654  * Also enforce alignment on the instance, not the type, to guarantee layout.
2655  */
2656 #define DEFINE_SCHED_CLASS(name) \
2657 const struct sched_class name##_sched_class \
2658 	__aligned(__alignof__(struct sched_class)) \
2659 	__section("__" #name "_sched_class")
2660 
2661 /* Defined in include/asm-generic/vmlinux.lds.h */
2662 extern struct sched_class __sched_class_highest[];
2663 extern struct sched_class __sched_class_lowest[];
2664 
2665 extern const struct sched_class stop_sched_class;
2666 extern const struct sched_class dl_sched_class;
2667 extern const struct sched_class rt_sched_class;
2668 extern const struct sched_class fair_sched_class;
2669 extern const struct sched_class idle_sched_class;
2670 
2671 /*
2672  * Iterate only active classes. SCX can take over all fair tasks or be
2673  * completely disabled. If the former, skip fair. If the latter, skip SCX.
2674  */
2675 static inline const struct sched_class *next_active_class(const struct sched_class *class)
2676 {
2677 	class++;
2678 #ifdef CONFIG_SCHED_CLASS_EXT
2679 	if (scx_switched_all() && class == &fair_sched_class)
2680 		class++;
2681 	if (!scx_enabled() && class == &ext_sched_class)
2682 		class++;
2683 #endif
2684 	return class;
2685 }
2686 
2687 #define for_class_range(class, _from, _to) \
2688 	for (class = (_from); class < (_to); class++)
2689 
2690 #define for_each_class(class) \
2691 	for_class_range(class, __sched_class_highest, __sched_class_lowest)
2692 
2693 #define for_active_class_range(class, _from, _to)				\
2694 	for (class = (_from); class != (_to); class = next_active_class(class))
2695 
2696 #define for_each_active_class(class)						\
2697 	for_active_class_range(class, __sched_class_highest, __sched_class_lowest)
2698 
2699 #define sched_class_above(_a, _b)	((_a) < (_b))
2700 
2701 static inline bool sched_stop_runnable(struct rq *rq)
2702 {
2703 	return rq->stop && task_on_rq_queued(rq->stop);
2704 }
2705 
2706 static inline bool sched_dl_runnable(struct rq *rq)
2707 {
2708 	return rq->dl.dl_nr_running > 0;
2709 }
2710 
2711 static inline bool sched_rt_runnable(struct rq *rq)
2712 {
2713 	return rq->rt.rt_queued > 0;
2714 }
2715 
2716 static inline bool sched_fair_runnable(struct rq *rq)
2717 {
2718 	return rq->cfs.nr_queued > 0;
2719 }
2720 
2721 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev,
2722 					       struct rq_flags *rf);
2723 extern struct task_struct *pick_task_idle(struct rq *rq, struct rq_flags *rf);
2724 
2725 #define SCA_CHECK		0x01
2726 #define SCA_MIGRATE_DISABLE	0x02
2727 #define SCA_MIGRATE_ENABLE	0x04
2728 #define SCA_USER		0x08
2729 
2730 extern void update_group_capacity(struct sched_domain *sd, int cpu);
2731 
2732 extern void sched_balance_trigger(struct rq *rq);
2733 
2734 extern int __set_cpus_allowed_ptr(struct task_struct *p, struct affinity_context *ctx);
2735 extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx);
2736 
2737 static inline bool task_allowed_on_cpu(struct task_struct *p, int cpu)
2738 {
2739 	/* When not in the task's cpumask, no point in looking further. */
2740 	if (!cpumask_test_cpu(cpu, p->cpus_ptr))
2741 		return false;
2742 
2743 	/* Can @cpu run a user thread? */
2744 	if (!(p->flags & PF_KTHREAD) && !task_cpu_possible(cpu, p))
2745 		return false;
2746 
2747 	return true;
2748 }
2749 
2750 static inline cpumask_t *alloc_user_cpus_ptr(int node)
2751 {
2752 	/*
2753 	 * See set_cpus_allowed_force() above for the rcu_head usage.
2754 	 */
2755 	int size = max_t(int, cpumask_size(), sizeof(struct rcu_head));
2756 
2757 	return kmalloc_node(size, GFP_KERNEL, node);
2758 }
2759 
2760 static inline struct task_struct *get_push_task(struct rq *rq)
2761 {
2762 	struct task_struct *p = rq->donor;
2763 
2764 	lockdep_assert_rq_held(rq);
2765 
2766 	if (rq->push_busy)
2767 		return NULL;
2768 
2769 	if (p->nr_cpus_allowed == 1)
2770 		return NULL;
2771 
2772 	if (p->migration_disabled)
2773 		return NULL;
2774 
2775 	rq->push_busy = true;
2776 	return get_task_struct(p);
2777 }
2778 
2779 extern int push_cpu_stop(void *arg);
2780 
2781 #ifdef CONFIG_CPU_IDLE
2782 
2783 static inline void idle_set_state(struct rq *rq,
2784 				  struct cpuidle_state *idle_state)
2785 {
2786 	rq->idle_state = idle_state;
2787 }
2788 
2789 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2790 {
2791 	WARN_ON_ONCE(!rcu_read_lock_held());
2792 
2793 	return rq->idle_state;
2794 }
2795 
2796 #else /* !CONFIG_CPU_IDLE: */
2797 
2798 static inline void idle_set_state(struct rq *rq,
2799 				  struct cpuidle_state *idle_state)
2800 {
2801 }
2802 
2803 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2804 {
2805 	return NULL;
2806 }
2807 
2808 #endif /* !CONFIG_CPU_IDLE */
2809 
2810 extern void schedule_idle(void);
2811 asmlinkage void schedule_user(void);
2812 
2813 extern void sysrq_sched_debug_show(void);
2814 extern void sched_init_granularity(void);
2815 extern void update_max_interval(void);
2816 
2817 extern void init_sched_dl_class(void);
2818 extern void init_sched_rt_class(void);
2819 extern void init_sched_fair_class(void);
2820 
2821 extern void resched_curr(struct rq *rq);
2822 extern void resched_curr_lazy(struct rq *rq);
2823 extern void resched_cpu(int cpu);
2824 
2825 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
2826 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq);
2827 
2828 extern void init_dl_entity(struct sched_dl_entity *dl_se);
2829 
2830 extern void init_cfs_throttle_work(struct task_struct *p);
2831 
2832 #define BW_SHIFT		20
2833 #define BW_UNIT			(1 << BW_SHIFT)
2834 #define RATIO_SHIFT		8
2835 #define MAX_BW_BITS		(64 - BW_SHIFT)
2836 #define MAX_BW			((1ULL << MAX_BW_BITS) - 1)
2837 
2838 extern unsigned long to_ratio(u64 period, u64 runtime);
2839 
2840 extern void init_entity_runnable_average(struct sched_entity *se);
2841 extern void post_init_entity_util_avg(struct task_struct *p);
2842 
2843 #ifdef CONFIG_NO_HZ_FULL
2844 extern bool sched_can_stop_tick(struct rq *rq);
2845 extern int __init sched_tick_offload_init(void);
2846 
2847 /*
2848  * Tick may be needed by tasks in the runqueue depending on their policy and
2849  * requirements. If tick is needed, lets send the target an IPI to kick it out of
2850  * nohz mode if necessary.
2851  */
2852 static inline void sched_update_tick_dependency(struct rq *rq)
2853 {
2854 	int cpu = cpu_of(rq);
2855 
2856 	if (!tick_nohz_full_cpu(cpu))
2857 		return;
2858 
2859 	if (sched_can_stop_tick(rq))
2860 		tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
2861 	else
2862 		tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
2863 }
2864 #else /* !CONFIG_NO_HZ_FULL: */
2865 static inline int sched_tick_offload_init(void) { return 0; }
2866 static inline void sched_update_tick_dependency(struct rq *rq) { }
2867 #endif /* !CONFIG_NO_HZ_FULL */
2868 
2869 static inline void add_nr_running(struct rq *rq, unsigned count)
2870 {
2871 	unsigned prev_nr = rq->nr_running;
2872 
2873 	rq->nr_running = prev_nr + count;
2874 	if (trace_sched_update_nr_running_tp_enabled()) {
2875 		call_trace_sched_update_nr_running(rq, count);
2876 	}
2877 
2878 	if (prev_nr < 2 && rq->nr_running >= 2)
2879 		set_rd_overloaded(rq->rd, 1);
2880 
2881 	sched_update_tick_dependency(rq);
2882 }
2883 
2884 static inline void sub_nr_running(struct rq *rq, unsigned count)
2885 {
2886 	rq->nr_running -= count;
2887 	if (trace_sched_update_nr_running_tp_enabled()) {
2888 		call_trace_sched_update_nr_running(rq, -count);
2889 	}
2890 
2891 	/* Check if we still need preemption */
2892 	sched_update_tick_dependency(rq);
2893 }
2894 
2895 static inline void __block_task(struct rq *rq, struct task_struct *p)
2896 {
2897 	if (p->sched_contributes_to_load)
2898 		rq->nr_uninterruptible++;
2899 
2900 	if (p->in_iowait) {
2901 		atomic_inc(&rq->nr_iowait);
2902 		delayacct_blkio_start();
2903 	}
2904 
2905 	ASSERT_EXCLUSIVE_WRITER(p->on_rq);
2906 
2907 	/*
2908 	 * The moment this write goes through, ttwu() can swoop in and migrate
2909 	 * this task, rendering our rq->__lock ineffective.
2910 	 *
2911 	 * __schedule()				try_to_wake_up()
2912 	 *   LOCK rq->__lock			  LOCK p->pi_lock
2913 	 *   pick_next_task()
2914 	 *     pick_next_task_fair()
2915 	 *       pick_next_entity()
2916 	 *         dequeue_entities()
2917 	 *           __block_task()
2918 	 *             RELEASE p->on_rq = 0	  if (p->on_rq && ...)
2919 	 *					    break;
2920 	 *
2921 	 *					  ACQUIRE (after ctrl-dep)
2922 	 *
2923 	 *					  cpu = select_task_rq();
2924 	 *					  set_task_cpu(p, cpu);
2925 	 *					  ttwu_queue()
2926 	 *					    ttwu_do_activate()
2927 	 *					      LOCK rq->__lock
2928 	 *					      activate_task()
2929 	 *					        STORE p->on_rq = 1
2930 	 *   UNLOCK rq->__lock
2931 	 *
2932 	 * Callers must ensure to not reference @p after this -- we no longer
2933 	 * own it.
2934 	 */
2935 	smp_store_release(&p->on_rq, 0);
2936 }
2937 
2938 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
2939 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
2940 
2941 extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags);
2942 
2943 #ifdef CONFIG_PREEMPT_RT
2944 # define SCHED_NR_MIGRATE_BREAK 8
2945 #else
2946 # define SCHED_NR_MIGRATE_BREAK 32
2947 #endif
2948 
2949 extern __read_mostly unsigned int sysctl_sched_nr_migrate;
2950 extern __read_mostly unsigned int sysctl_sched_migration_cost;
2951 
2952 extern unsigned int sysctl_sched_base_slice;
2953 
2954 extern int sysctl_resched_latency_warn_ms;
2955 extern int sysctl_resched_latency_warn_once;
2956 
2957 extern unsigned int sysctl_sched_tunable_scaling;
2958 
2959 extern unsigned int sysctl_numa_balancing_scan_delay;
2960 extern unsigned int sysctl_numa_balancing_scan_period_min;
2961 extern unsigned int sysctl_numa_balancing_scan_period_max;
2962 extern unsigned int sysctl_numa_balancing_scan_size;
2963 extern unsigned int sysctl_numa_balancing_hot_threshold;
2964 
2965 #ifdef CONFIG_SCHED_HRTICK
2966 
2967 /*
2968  * Use hrtick when:
2969  *  - enabled by features
2970  *  - hrtimer is actually high res
2971  */
2972 static inline int hrtick_enabled(struct rq *rq)
2973 {
2974 	if (!cpu_active(cpu_of(rq)))
2975 		return 0;
2976 	return hrtimer_is_hres_active(&rq->hrtick_timer);
2977 }
2978 
2979 static inline int hrtick_enabled_fair(struct rq *rq)
2980 {
2981 	if (!sched_feat(HRTICK))
2982 		return 0;
2983 	return hrtick_enabled(rq);
2984 }
2985 
2986 static inline int hrtick_enabled_dl(struct rq *rq)
2987 {
2988 	if (!sched_feat(HRTICK_DL))
2989 		return 0;
2990 	return hrtick_enabled(rq);
2991 }
2992 
2993 extern void hrtick_start(struct rq *rq, u64 delay);
2994 
2995 #else /* !CONFIG_SCHED_HRTICK: */
2996 
2997 static inline int hrtick_enabled_fair(struct rq *rq)
2998 {
2999 	return 0;
3000 }
3001 
3002 static inline int hrtick_enabled_dl(struct rq *rq)
3003 {
3004 	return 0;
3005 }
3006 
3007 static inline int hrtick_enabled(struct rq *rq)
3008 {
3009 	return 0;
3010 }
3011 
3012 #endif /* !CONFIG_SCHED_HRTICK */
3013 
3014 #ifndef arch_scale_freq_tick
3015 static __always_inline void arch_scale_freq_tick(void) { }
3016 #endif
3017 
3018 #ifndef arch_scale_freq_capacity
3019 /**
3020  * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
3021  * @cpu: the CPU in question.
3022  *
3023  * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
3024  *
3025  *     f_curr
3026  *     ------ * SCHED_CAPACITY_SCALE
3027  *     f_max
3028  */
3029 static __always_inline
3030 unsigned long arch_scale_freq_capacity(int cpu)
3031 {
3032 	return SCHED_CAPACITY_SCALE;
3033 }
3034 #endif
3035 
3036 /*
3037  * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to
3038  * acquire rq lock instead of rq_lock(). So at the end of these two functions
3039  * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of
3040  * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning.
3041  */
3042 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2)
3043 {
3044 	rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
3045 	rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
3046 }
3047 
3048 #define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...)				\
3049 __DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__)			\
3050 static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2)	\
3051 { class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t;			\
3052   _lock; return _t; }
3053 
3054 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2)
3055 {
3056 #ifdef CONFIG_SCHED_CORE
3057 	/*
3058 	 * In order to not have {0,2},{1,3} turn into into an AB-BA,
3059 	 * order by core-id first and cpu-id second.
3060 	 *
3061 	 * Notably:
3062 	 *
3063 	 *	double_rq_lock(0,3); will take core-0, core-1 lock
3064 	 *	double_rq_lock(1,2); will take core-1, core-0 lock
3065 	 *
3066 	 * when only cpu-id is considered.
3067 	 */
3068 	if (rq1->core->cpu < rq2->core->cpu)
3069 		return true;
3070 	if (rq1->core->cpu > rq2->core->cpu)
3071 		return false;
3072 
3073 	/*
3074 	 * __sched_core_flip() relies on SMT having cpu-id lock order.
3075 	 */
3076 #endif /* CONFIG_SCHED_CORE */
3077 	return rq1->cpu < rq2->cpu;
3078 }
3079 
3080 extern void double_rq_lock(struct rq *rq1, struct rq *rq2);
3081 
3082 #ifdef CONFIG_PREEMPTION
3083 
3084 /*
3085  * fair double_lock_balance: Safely acquires both rq->locks in a fair
3086  * way at the expense of forcing extra atomic operations in all
3087  * invocations.  This assures that the double_lock is acquired using the
3088  * same underlying policy as the spinlock_t on this architecture, which
3089  * reduces latency compared to the unfair variant below.  However, it
3090  * also adds more overhead and therefore may reduce throughput.
3091  */
3092 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
3093 	__releases(this_rq->lock)
3094 	__acquires(busiest->lock)
3095 	__acquires(this_rq->lock)
3096 {
3097 	raw_spin_rq_unlock(this_rq);
3098 	double_rq_lock(this_rq, busiest);
3099 
3100 	return 1;
3101 }
3102 
3103 #else /* !CONFIG_PREEMPTION: */
3104 /*
3105  * Unfair double_lock_balance: Optimizes throughput at the expense of
3106  * latency by eliminating extra atomic operations when the locks are
3107  * already in proper order on entry.  This favors lower CPU-ids and will
3108  * grant the double lock to lower CPUs over higher ids under contention,
3109  * regardless of entry order into the function.
3110  */
3111 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
3112 	__releases(this_rq->lock)
3113 	__acquires(busiest->lock)
3114 	__acquires(this_rq->lock)
3115 {
3116 	if (__rq_lockp(this_rq) == __rq_lockp(busiest) ||
3117 	    likely(raw_spin_rq_trylock(busiest))) {
3118 		double_rq_clock_clear_update(this_rq, busiest);
3119 		return 0;
3120 	}
3121 
3122 	if (rq_order_less(this_rq, busiest)) {
3123 		raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING);
3124 		double_rq_clock_clear_update(this_rq, busiest);
3125 		return 0;
3126 	}
3127 
3128 	raw_spin_rq_unlock(this_rq);
3129 	double_rq_lock(this_rq, busiest);
3130 
3131 	return 1;
3132 }
3133 
3134 #endif /* !CONFIG_PREEMPTION */
3135 
3136 /*
3137  * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
3138  */
3139 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
3140 {
3141 	lockdep_assert_irqs_disabled();
3142 
3143 	return _double_lock_balance(this_rq, busiest);
3144 }
3145 
3146 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
3147 	__releases(busiest->lock)
3148 {
3149 	if (__rq_lockp(this_rq) != __rq_lockp(busiest))
3150 		raw_spin_rq_unlock(busiest);
3151 	lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_);
3152 }
3153 
3154 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
3155 {
3156 	if (l1 > l2)
3157 		swap(l1, l2);
3158 
3159 	spin_lock(l1);
3160 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3161 }
3162 
3163 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
3164 {
3165 	if (l1 > l2)
3166 		swap(l1, l2);
3167 
3168 	spin_lock_irq(l1);
3169 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3170 }
3171 
3172 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
3173 {
3174 	if (l1 > l2)
3175 		swap(l1, l2);
3176 
3177 	raw_spin_lock(l1);
3178 	raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3179 }
3180 
3181 static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2)
3182 {
3183 	raw_spin_unlock(l1);
3184 	raw_spin_unlock(l2);
3185 }
3186 
3187 DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t,
3188 		    double_raw_lock(_T->lock, _T->lock2),
3189 		    double_raw_unlock(_T->lock, _T->lock2))
3190 
3191 /*
3192  * double_rq_unlock - safely unlock two runqueues
3193  *
3194  * Note this does not restore interrupts like task_rq_unlock,
3195  * you need to do so manually after calling.
3196  */
3197 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
3198 	__releases(rq1->lock)
3199 	__releases(rq2->lock)
3200 {
3201 	if (__rq_lockp(rq1) != __rq_lockp(rq2))
3202 		raw_spin_rq_unlock(rq2);
3203 	else
3204 		__release(rq2->lock);
3205 	raw_spin_rq_unlock(rq1);
3206 }
3207 
3208 extern void set_rq_online (struct rq *rq);
3209 extern void set_rq_offline(struct rq *rq);
3210 
3211 extern bool sched_smp_initialized;
3212 
3213 DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq,
3214 		    double_rq_lock(_T->lock, _T->lock2),
3215 		    double_rq_unlock(_T->lock, _T->lock2))
3216 
3217 extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq);
3218 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
3219 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
3220 
3221 extern bool sched_debug_verbose;
3222 
3223 extern void print_cfs_stats(struct seq_file *m, int cpu);
3224 extern void print_rt_stats(struct seq_file *m, int cpu);
3225 extern void print_dl_stats(struct seq_file *m, int cpu);
3226 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
3227 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
3228 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
3229 
3230 extern void resched_latency_warn(int cpu, u64 latency);
3231 
3232 #ifdef CONFIG_NUMA_BALANCING
3233 extern void show_numa_stats(struct task_struct *p, struct seq_file *m);
3234 extern void
3235 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
3236 		 unsigned long tpf, unsigned long gsf, unsigned long gpf);
3237 #endif /* CONFIG_NUMA_BALANCING */
3238 
3239 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
3240 extern void init_rt_rq(struct rt_rq *rt_rq);
3241 extern void init_dl_rq(struct dl_rq *dl_rq);
3242 
3243 extern void cfs_bandwidth_usage_inc(void);
3244 extern void cfs_bandwidth_usage_dec(void);
3245 
3246 #ifdef CONFIG_NO_HZ_COMMON
3247 
3248 #define NOHZ_BALANCE_KICK_BIT	0
3249 #define NOHZ_STATS_KICK_BIT	1
3250 #define NOHZ_NEWILB_KICK_BIT	2
3251 #define NOHZ_NEXT_KICK_BIT	3
3252 
3253 /* Run sched_balance_domains() */
3254 #define NOHZ_BALANCE_KICK	BIT(NOHZ_BALANCE_KICK_BIT)
3255 /* Update blocked load */
3256 #define NOHZ_STATS_KICK		BIT(NOHZ_STATS_KICK_BIT)
3257 /* Update blocked load when entering idle */
3258 #define NOHZ_NEWILB_KICK	BIT(NOHZ_NEWILB_KICK_BIT)
3259 /* Update nohz.next_balance */
3260 #define NOHZ_NEXT_KICK		BIT(NOHZ_NEXT_KICK_BIT)
3261 
3262 #define NOHZ_KICK_MASK		(NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK)
3263 
3264 #define nohz_flags(cpu)		(&cpu_rq(cpu)->nohz_flags)
3265 
3266 extern void nohz_balance_exit_idle(struct rq *rq);
3267 #else /* !CONFIG_NO_HZ_COMMON: */
3268 static inline void nohz_balance_exit_idle(struct rq *rq) { }
3269 #endif /* !CONFIG_NO_HZ_COMMON */
3270 
3271 #ifdef CONFIG_NO_HZ_COMMON
3272 extern void nohz_run_idle_balance(int cpu);
3273 #else
3274 static inline void nohz_run_idle_balance(int cpu) { }
3275 #endif
3276 
3277 #include "stats.h"
3278 
3279 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS)
3280 
3281 extern void __sched_core_account_forceidle(struct rq *rq);
3282 
3283 static inline void sched_core_account_forceidle(struct rq *rq)
3284 {
3285 	if (schedstat_enabled())
3286 		__sched_core_account_forceidle(rq);
3287 }
3288 
3289 extern void __sched_core_tick(struct rq *rq);
3290 
3291 static inline void sched_core_tick(struct rq *rq)
3292 {
3293 	if (sched_core_enabled(rq) && schedstat_enabled())
3294 		__sched_core_tick(rq);
3295 }
3296 
3297 #else /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS): */
3298 
3299 static inline void sched_core_account_forceidle(struct rq *rq) { }
3300 
3301 static inline void sched_core_tick(struct rq *rq) { }
3302 
3303 #endif /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS) */
3304 
3305 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
3306 
3307 struct irqtime {
3308 	u64			total;
3309 	u64			tick_delta;
3310 	u64			irq_start_time;
3311 	struct u64_stats_sync	sync;
3312 };
3313 
3314 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
3315 extern int sched_clock_irqtime;
3316 
3317 static inline int irqtime_enabled(void)
3318 {
3319 	return sched_clock_irqtime;
3320 }
3321 
3322 /*
3323  * Returns the irqtime minus the softirq time computed by ksoftirqd.
3324  * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime
3325  * and never move forward.
3326  */
3327 static inline u64 irq_time_read(int cpu)
3328 {
3329 	struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
3330 	unsigned int seq;
3331 	u64 total;
3332 
3333 	do {
3334 		seq = __u64_stats_fetch_begin(&irqtime->sync);
3335 		total = irqtime->total;
3336 	} while (__u64_stats_fetch_retry(&irqtime->sync, seq));
3337 
3338 	return total;
3339 }
3340 
3341 #else /* !CONFIG_IRQ_TIME_ACCOUNTING: */
3342 
3343 static inline int irqtime_enabled(void)
3344 {
3345 	return 0;
3346 }
3347 
3348 #endif /* !CONFIG_IRQ_TIME_ACCOUNTING */
3349 
3350 #ifdef CONFIG_CPU_FREQ
3351 
3352 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
3353 
3354 /**
3355  * cpufreq_update_util - Take a note about CPU utilization changes.
3356  * @rq: Runqueue to carry out the update for.
3357  * @flags: Update reason flags.
3358  *
3359  * This function is called by the scheduler on the CPU whose utilization is
3360  * being updated.
3361  *
3362  * It can only be called from RCU-sched read-side critical sections.
3363  *
3364  * The way cpufreq is currently arranged requires it to evaluate the CPU
3365  * performance state (frequency/voltage) on a regular basis to prevent it from
3366  * being stuck in a completely inadequate performance level for too long.
3367  * That is not guaranteed to happen if the updates are only triggered from CFS
3368  * and DL, though, because they may not be coming in if only RT tasks are
3369  * active all the time (or there are RT tasks only).
3370  *
3371  * As a workaround for that issue, this function is called periodically by the
3372  * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
3373  * but that really is a band-aid.  Going forward it should be replaced with
3374  * solutions targeted more specifically at RT tasks.
3375  */
3376 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
3377 {
3378 	struct update_util_data *data;
3379 
3380 	data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
3381 						  cpu_of(rq)));
3382 	if (data)
3383 		data->func(data, rq_clock(rq), flags);
3384 }
3385 #else /* !CONFIG_CPU_FREQ: */
3386 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) { }
3387 #endif /* !CONFIG_CPU_FREQ */
3388 
3389 #ifdef arch_scale_freq_capacity
3390 # ifndef arch_scale_freq_invariant
3391 #  define arch_scale_freq_invariant()	true
3392 # endif
3393 #else
3394 # define arch_scale_freq_invariant()	false
3395 #endif
3396 
3397 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
3398 				 unsigned long *min,
3399 				 unsigned long *max);
3400 
3401 unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual,
3402 				 unsigned long min,
3403 				 unsigned long max);
3404 
3405 
3406 /*
3407  * Verify the fitness of task @p to run on @cpu taking into account the
3408  * CPU original capacity and the runtime/deadline ratio of the task.
3409  *
3410  * The function will return true if the original capacity of @cpu is
3411  * greater than or equal to task's deadline density right shifted by
3412  * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise.
3413  */
3414 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
3415 {
3416 	unsigned long cap = arch_scale_cpu_capacity(cpu);
3417 
3418 	return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT);
3419 }
3420 
3421 static inline unsigned long cpu_bw_dl(struct rq *rq)
3422 {
3423 	return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
3424 }
3425 
3426 static inline unsigned long cpu_util_dl(struct rq *rq)
3427 {
3428 	return READ_ONCE(rq->avg_dl.util_avg);
3429 }
3430 
3431 
3432 extern unsigned long cpu_util_cfs(int cpu);
3433 extern unsigned long cpu_util_cfs_boost(int cpu);
3434 
3435 static inline unsigned long cpu_util_rt(struct rq *rq)
3436 {
3437 	return READ_ONCE(rq->avg_rt.util_avg);
3438 }
3439 
3440 #ifdef CONFIG_UCLAMP_TASK
3441 
3442 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
3443 
3444 /*
3445  * When uclamp is compiled in, the aggregation at rq level is 'turned off'
3446  * by default in the fast path and only gets turned on once userspace performs
3447  * an operation that requires it.
3448  *
3449  * Returns true if userspace opted-in to use uclamp and aggregation at rq level
3450  * hence is active.
3451  */
3452 static inline bool uclamp_is_used(void)
3453 {
3454 	return static_branch_likely(&sched_uclamp_used);
3455 }
3456 
3457 /*
3458  * Enabling static branches would get the cpus_read_lock(),
3459  * check whether uclamp_is_used before enable it to avoid always
3460  * calling cpus_read_lock(). Because we never disable this
3461  * static key once enable it.
3462  */
3463 static inline void sched_uclamp_enable(void)
3464 {
3465 	if (!uclamp_is_used())
3466 		static_branch_enable(&sched_uclamp_used);
3467 }
3468 
3469 static inline unsigned long uclamp_rq_get(struct rq *rq,
3470 					  enum uclamp_id clamp_id)
3471 {
3472 	return READ_ONCE(rq->uclamp[clamp_id].value);
3473 }
3474 
3475 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id,
3476 				 unsigned int value)
3477 {
3478 	WRITE_ONCE(rq->uclamp[clamp_id].value, value);
3479 }
3480 
3481 static inline bool uclamp_rq_is_idle(struct rq *rq)
3482 {
3483 	return rq->uclamp_flags & UCLAMP_FLAG_IDLE;
3484 }
3485 
3486 /* Is the rq being capped/throttled by uclamp_max? */
3487 static inline bool uclamp_rq_is_capped(struct rq *rq)
3488 {
3489 	unsigned long rq_util;
3490 	unsigned long max_util;
3491 
3492 	if (!uclamp_is_used())
3493 		return false;
3494 
3495 	rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq);
3496 	max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
3497 
3498 	return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util;
3499 }
3500 
3501 #define for_each_clamp_id(clamp_id) \
3502 	for ((clamp_id) = 0; (clamp_id) < UCLAMP_CNT; (clamp_id)++)
3503 
3504 extern unsigned int sysctl_sched_uclamp_util_min_rt_default;
3505 
3506 
3507 static inline unsigned int uclamp_none(enum uclamp_id clamp_id)
3508 {
3509 	if (clamp_id == UCLAMP_MIN)
3510 		return 0;
3511 	return SCHED_CAPACITY_SCALE;
3512 }
3513 
3514 /* Integer rounded range for each bucket */
3515 #define UCLAMP_BUCKET_DELTA DIV_ROUND_CLOSEST(SCHED_CAPACITY_SCALE, UCLAMP_BUCKETS)
3516 
3517 static inline unsigned int uclamp_bucket_id(unsigned int clamp_value)
3518 {
3519 	return min_t(unsigned int, clamp_value / UCLAMP_BUCKET_DELTA, UCLAMP_BUCKETS - 1);
3520 }
3521 
3522 static inline void
3523 uclamp_se_set(struct uclamp_se *uc_se, unsigned int value, bool user_defined)
3524 {
3525 	uc_se->value = value;
3526 	uc_se->bucket_id = uclamp_bucket_id(value);
3527 	uc_se->user_defined = user_defined;
3528 }
3529 
3530 #else /* !CONFIG_UCLAMP_TASK: */
3531 
3532 static inline unsigned long
3533 uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id)
3534 {
3535 	if (clamp_id == UCLAMP_MIN)
3536 		return 0;
3537 
3538 	return SCHED_CAPACITY_SCALE;
3539 }
3540 
3541 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; }
3542 
3543 static inline bool uclamp_is_used(void)
3544 {
3545 	return false;
3546 }
3547 
3548 static inline void sched_uclamp_enable(void) {}
3549 
3550 static inline unsigned long
3551 uclamp_rq_get(struct rq *rq, enum uclamp_id clamp_id)
3552 {
3553 	if (clamp_id == UCLAMP_MIN)
3554 		return 0;
3555 
3556 	return SCHED_CAPACITY_SCALE;
3557 }
3558 
3559 static inline void
3560 uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, unsigned int value)
3561 {
3562 }
3563 
3564 static inline bool uclamp_rq_is_idle(struct rq *rq)
3565 {
3566 	return false;
3567 }
3568 
3569 #endif /* !CONFIG_UCLAMP_TASK */
3570 
3571 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
3572 
3573 static inline unsigned long cpu_util_irq(struct rq *rq)
3574 {
3575 	return READ_ONCE(rq->avg_irq.util_avg);
3576 }
3577 
3578 static inline
3579 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3580 {
3581 	util *= (max - irq);
3582 	util /= max;
3583 
3584 	return util;
3585 
3586 }
3587 
3588 #else /* !CONFIG_HAVE_SCHED_AVG_IRQ: */
3589 
3590 static inline unsigned long cpu_util_irq(struct rq *rq)
3591 {
3592 	return 0;
3593 }
3594 
3595 static inline
3596 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3597 {
3598 	return util;
3599 }
3600 
3601 #endif /* !CONFIG_HAVE_SCHED_AVG_IRQ */
3602 
3603 extern void __setparam_fair(struct task_struct *p, const struct sched_attr *attr);
3604 
3605 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
3606 
3607 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
3608 
3609 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
3610 
3611 static inline bool sched_energy_enabled(void)
3612 {
3613 	return static_branch_unlikely(&sched_energy_present);
3614 }
3615 
3616 #else /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL): */
3617 
3618 #define perf_domain_span(pd) NULL
3619 
3620 static inline bool sched_energy_enabled(void) { return false; }
3621 
3622 #endif /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
3623 
3624 #ifdef CONFIG_MEMBARRIER
3625 
3626 /*
3627  * The scheduler provides memory barriers required by membarrier between:
3628  * - prior user-space memory accesses and store to rq->membarrier_state,
3629  * - store to rq->membarrier_state and following user-space memory accesses.
3630  * In the same way it provides those guarantees around store to rq->curr.
3631  */
3632 static inline void membarrier_switch_mm(struct rq *rq,
3633 					struct mm_struct *prev_mm,
3634 					struct mm_struct *next_mm)
3635 {
3636 	int membarrier_state;
3637 
3638 	if (prev_mm == next_mm)
3639 		return;
3640 
3641 	membarrier_state = atomic_read(&next_mm->membarrier_state);
3642 	if (READ_ONCE(rq->membarrier_state) == membarrier_state)
3643 		return;
3644 
3645 	WRITE_ONCE(rq->membarrier_state, membarrier_state);
3646 }
3647 
3648 #else /* !CONFIG_MEMBARRIER: */
3649 
3650 static inline void membarrier_switch_mm(struct rq *rq,
3651 					struct mm_struct *prev_mm,
3652 					struct mm_struct *next_mm)
3653 {
3654 }
3655 
3656 #endif /* !CONFIG_MEMBARRIER */
3657 
3658 static inline bool is_per_cpu_kthread(struct task_struct *p)
3659 {
3660 	if (!(p->flags & PF_KTHREAD))
3661 		return false;
3662 
3663 	if (p->nr_cpus_allowed != 1)
3664 		return false;
3665 
3666 	return true;
3667 }
3668 
3669 extern void swake_up_all_locked(struct swait_queue_head *q);
3670 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
3671 
3672 extern int try_to_wake_up(struct task_struct *tsk, unsigned int state, int wake_flags);
3673 
3674 #ifdef CONFIG_PREEMPT_DYNAMIC
3675 extern int preempt_dynamic_mode;
3676 extern int sched_dynamic_mode(const char *str);
3677 extern void sched_dynamic_update(int mode);
3678 #endif
3679 extern const char *preempt_modes[];
3680 
3681 #ifdef CONFIG_SCHED_MM_CID
3682 
3683 static __always_inline bool cid_on_cpu(unsigned int cid)
3684 {
3685 	return cid & MM_CID_ONCPU;
3686 }
3687 
3688 static __always_inline bool cid_in_transit(unsigned int cid)
3689 {
3690 	return cid & MM_CID_TRANSIT;
3691 }
3692 
3693 static __always_inline unsigned int cpu_cid_to_cid(unsigned int cid)
3694 {
3695 	return cid & ~MM_CID_ONCPU;
3696 }
3697 
3698 static __always_inline unsigned int cid_to_cpu_cid(unsigned int cid)
3699 {
3700 	return cid | MM_CID_ONCPU;
3701 }
3702 
3703 static __always_inline unsigned int cid_to_transit_cid(unsigned int cid)
3704 {
3705 	return cid | MM_CID_TRANSIT;
3706 }
3707 
3708 static __always_inline unsigned int cid_from_transit_cid(unsigned int cid)
3709 {
3710 	return cid & ~MM_CID_TRANSIT;
3711 }
3712 
3713 static __always_inline bool cid_on_task(unsigned int cid)
3714 {
3715 	/* True if none of the MM_CID_ONCPU, MM_CID_TRANSIT, MM_CID_UNSET bits is set */
3716 	return cid < MM_CID_TRANSIT;
3717 }
3718 
3719 static __always_inline void mm_drop_cid(struct mm_struct *mm, unsigned int cid)
3720 {
3721 	clear_bit(cid, mm_cidmask(mm));
3722 }
3723 
3724 static __always_inline void mm_unset_cid_on_task(struct task_struct *t)
3725 {
3726 	unsigned int cid = t->mm_cid.cid;
3727 
3728 	t->mm_cid.cid = MM_CID_UNSET;
3729 	if (cid_on_task(cid))
3730 		mm_drop_cid(t->mm, cid);
3731 }
3732 
3733 static __always_inline void mm_drop_cid_on_cpu(struct mm_struct *mm, struct mm_cid_pcpu *pcp)
3734 {
3735 	/* Clear the ONCPU bit, but do not set UNSET in the per CPU storage */
3736 	pcp->cid = cpu_cid_to_cid(pcp->cid);
3737 	mm_drop_cid(mm, pcp->cid);
3738 }
3739 
3740 static inline unsigned int __mm_get_cid(struct mm_struct *mm, unsigned int max_cids)
3741 {
3742 	unsigned int cid = find_first_zero_bit(mm_cidmask(mm), max_cids);
3743 
3744 	if (cid >= max_cids)
3745 		return MM_CID_UNSET;
3746 	if (test_and_set_bit(cid, mm_cidmask(mm)))
3747 		return MM_CID_UNSET;
3748 	return cid;
3749 }
3750 
3751 static inline unsigned int mm_get_cid(struct mm_struct *mm)
3752 {
3753 	unsigned int cid = __mm_get_cid(mm, READ_ONCE(mm->mm_cid.max_cids));
3754 
3755 	while (cid == MM_CID_UNSET) {
3756 		cpu_relax();
3757 		cid = __mm_get_cid(mm, num_possible_cpus());
3758 	}
3759 	return cid;
3760 }
3761 
3762 static inline unsigned int mm_cid_converge(struct mm_struct *mm, unsigned int orig_cid,
3763 					   unsigned int max_cids)
3764 {
3765 	unsigned int new_cid, cid = cpu_cid_to_cid(orig_cid);
3766 
3767 	/* Is it in the optimal CID space? */
3768 	if (likely(cid < max_cids))
3769 		return orig_cid;
3770 
3771 	/* Try to find one in the optimal space. Otherwise keep the provided. */
3772 	new_cid = __mm_get_cid(mm, max_cids);
3773 	if (new_cid != MM_CID_UNSET) {
3774 		mm_drop_cid(mm, cid);
3775 		/* Preserve the ONCPU mode of the original CID */
3776 		return new_cid | (orig_cid & MM_CID_ONCPU);
3777 	}
3778 	return orig_cid;
3779 }
3780 
3781 static __always_inline void mm_cid_update_task_cid(struct task_struct *t, unsigned int cid)
3782 {
3783 	if (t->mm_cid.cid != cid) {
3784 		t->mm_cid.cid = cid;
3785 		rseq_sched_set_ids_changed(t);
3786 	}
3787 }
3788 
3789 static __always_inline void mm_cid_update_pcpu_cid(struct mm_struct *mm, unsigned int cid)
3790 {
3791 	__this_cpu_write(mm->mm_cid.pcpu->cid, cid);
3792 }
3793 
3794 static __always_inline void mm_cid_from_cpu(struct task_struct *t, unsigned int cpu_cid)
3795 {
3796 	unsigned int max_cids, tcid = t->mm_cid.cid;
3797 	struct mm_struct *mm = t->mm;
3798 
3799 	max_cids = READ_ONCE(mm->mm_cid.max_cids);
3800 	/* Optimize for the common case where both have the ONCPU bit set */
3801 	if (likely(cid_on_cpu(cpu_cid & tcid))) {
3802 		if (likely(cpu_cid_to_cid(cpu_cid) < max_cids)) {
3803 			mm_cid_update_task_cid(t, cpu_cid);
3804 			return;
3805 		}
3806 		/* Try to converge into the optimal CID space */
3807 		cpu_cid = mm_cid_converge(mm, cpu_cid, max_cids);
3808 	} else {
3809 		/* Hand over or drop the task owned CID */
3810 		if (cid_on_task(tcid)) {
3811 			if (cid_on_cpu(cpu_cid))
3812 				mm_unset_cid_on_task(t);
3813 			else
3814 				cpu_cid = cid_to_cpu_cid(tcid);
3815 		}
3816 		/* Still nothing, allocate a new one */
3817 		if (!cid_on_cpu(cpu_cid))
3818 			cpu_cid = cid_to_cpu_cid(mm_get_cid(mm));
3819 	}
3820 	mm_cid_update_pcpu_cid(mm, cpu_cid);
3821 	mm_cid_update_task_cid(t, cpu_cid);
3822 }
3823 
3824 static __always_inline void mm_cid_from_task(struct task_struct *t, unsigned int cpu_cid)
3825 {
3826 	unsigned int max_cids, tcid = t->mm_cid.cid;
3827 	struct mm_struct *mm = t->mm;
3828 
3829 	max_cids = READ_ONCE(mm->mm_cid.max_cids);
3830 	/* Optimize for the common case, where both have the ONCPU bit clear */
3831 	if (likely(cid_on_task(tcid | cpu_cid))) {
3832 		if (likely(tcid < max_cids)) {
3833 			mm_cid_update_pcpu_cid(mm, tcid);
3834 			return;
3835 		}
3836 		/* Try to converge into the optimal CID space */
3837 		tcid = mm_cid_converge(mm, tcid, max_cids);
3838 	} else {
3839 		/* Hand over or drop the CPU owned CID */
3840 		if (cid_on_cpu(cpu_cid)) {
3841 			if (cid_on_task(tcid))
3842 				mm_drop_cid_on_cpu(mm, this_cpu_ptr(mm->mm_cid.pcpu));
3843 			else
3844 				tcid = cpu_cid_to_cid(cpu_cid);
3845 		}
3846 		/* Still nothing, allocate a new one */
3847 		if (!cid_on_task(tcid))
3848 			tcid = mm_get_cid(mm);
3849 		/* Set the transition mode flag if required */
3850 		tcid |= READ_ONCE(mm->mm_cid.transit);
3851 	}
3852 	mm_cid_update_pcpu_cid(mm, tcid);
3853 	mm_cid_update_task_cid(t, tcid);
3854 }
3855 
3856 static __always_inline void mm_cid_schedin(struct task_struct *next)
3857 {
3858 	struct mm_struct *mm = next->mm;
3859 	unsigned int cpu_cid;
3860 
3861 	if (!next->mm_cid.active)
3862 		return;
3863 
3864 	cpu_cid = __this_cpu_read(mm->mm_cid.pcpu->cid);
3865 	if (likely(!READ_ONCE(mm->mm_cid.percpu)))
3866 		mm_cid_from_task(next, cpu_cid);
3867 	else
3868 		mm_cid_from_cpu(next, cpu_cid);
3869 }
3870 
3871 static __always_inline void mm_cid_schedout(struct task_struct *prev)
3872 {
3873 	/* During mode transitions CIDs are temporary and need to be dropped */
3874 	if (likely(!cid_in_transit(prev->mm_cid.cid)))
3875 		return;
3876 
3877 	mm_drop_cid(prev->mm, cid_from_transit_cid(prev->mm_cid.cid));
3878 	prev->mm_cid.cid = MM_CID_UNSET;
3879 }
3880 
3881 static inline void mm_cid_switch_to(struct task_struct *prev, struct task_struct *next)
3882 {
3883 	mm_cid_schedout(prev);
3884 	mm_cid_schedin(next);
3885 }
3886 
3887 #else /* !CONFIG_SCHED_MM_CID: */
3888 static inline void mm_cid_switch_to(struct task_struct *prev, struct task_struct *next) { }
3889 #endif /* !CONFIG_SCHED_MM_CID */
3890 
3891 extern u64 avg_vruntime(struct cfs_rq *cfs_rq);
3892 extern int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se);
3893 static inline
3894 void move_queued_task_locked(struct rq *src_rq, struct rq *dst_rq, struct task_struct *task)
3895 {
3896 	lockdep_assert_rq_held(src_rq);
3897 	lockdep_assert_rq_held(dst_rq);
3898 
3899 	deactivate_task(src_rq, task, 0);
3900 	set_task_cpu(task, dst_rq->cpu);
3901 	activate_task(dst_rq, task, 0);
3902 }
3903 
3904 static inline
3905 bool task_is_pushable(struct rq *rq, struct task_struct *p, int cpu)
3906 {
3907 	if (!task_on_cpu(rq, p) &&
3908 	    cpumask_test_cpu(cpu, &p->cpus_mask))
3909 		return true;
3910 
3911 	return false;
3912 }
3913 
3914 #ifdef CONFIG_RT_MUTEXES
3915 
3916 static inline int __rt_effective_prio(struct task_struct *pi_task, int prio)
3917 {
3918 	if (pi_task)
3919 		prio = min(prio, pi_task->prio);
3920 
3921 	return prio;
3922 }
3923 
3924 static inline int rt_effective_prio(struct task_struct *p, int prio)
3925 {
3926 	struct task_struct *pi_task = rt_mutex_get_top_task(p);
3927 
3928 	return __rt_effective_prio(pi_task, prio);
3929 }
3930 
3931 #else /* !CONFIG_RT_MUTEXES: */
3932 
3933 static inline int rt_effective_prio(struct task_struct *p, int prio)
3934 {
3935 	return prio;
3936 }
3937 
3938 #endif /* !CONFIG_RT_MUTEXES */
3939 
3940 extern int __sched_setscheduler(struct task_struct *p, const struct sched_attr *attr, bool user, bool pi);
3941 extern int __sched_setaffinity(struct task_struct *p, struct affinity_context *ctx);
3942 extern const struct sched_class *__setscheduler_class(int policy, int prio);
3943 extern void set_load_weight(struct task_struct *p, bool update_load);
3944 extern void enqueue_task(struct rq *rq, struct task_struct *p, int flags);
3945 extern bool dequeue_task(struct rq *rq, struct task_struct *p, int flags);
3946 
3947 extern struct balance_callback *splice_balance_callbacks(struct rq *rq);
3948 extern void balance_callbacks(struct rq *rq, struct balance_callback *head);
3949 
3950 /*
3951  * The 'sched_change' pattern is the safe, easy and slow way of changing a
3952  * task's scheduling properties. It dequeues a task, such that the scheduler
3953  * is fully unaware of it; at which point its properties can be modified;
3954  * after which it is enqueued again.
3955  *
3956  * Typically this must be called while holding task_rq_lock, since most/all
3957  * properties are serialized under those locks. There is currently one
3958  * exception to this rule in sched/ext which only holds rq->lock.
3959  */
3960 
3961 /*
3962  * This structure is a temporary, used to preserve/convey the queueing state
3963  * of the task between sched_change_begin() and sched_change_end(). Ensuring
3964  * the task's queueing state is idempotent across the operation.
3965  */
3966 struct sched_change_ctx {
3967 	u64			prio;
3968 	struct task_struct	*p;
3969 	int			flags;
3970 	bool			queued;
3971 	bool			running;
3972 };
3973 
3974 struct sched_change_ctx *sched_change_begin(struct task_struct *p, unsigned int flags);
3975 void sched_change_end(struct sched_change_ctx *ctx);
3976 
3977 DEFINE_CLASS(sched_change, struct sched_change_ctx *,
3978 	     sched_change_end(_T),
3979 	     sched_change_begin(p, flags),
3980 	     struct task_struct *p, unsigned int flags)
3981 
3982 DEFINE_CLASS_IS_UNCONDITIONAL(sched_change)
3983 
3984 #include "ext.h"
3985 
3986 #endif /* _KERNEL_SCHED_SCHED_H */
3987