xref: /linux/kernel/sched/sched.h (revision a3f5d48222532484c1e85ef27cc6893803e4cd17)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Scheduler internal types and methods:
4  */
5 #ifndef _KERNEL_SCHED_SCHED_H
6 #define _KERNEL_SCHED_SCHED_H
7 
8 #include <linux/sched/affinity.h>
9 #include <linux/sched/autogroup.h>
10 #include <linux/sched/cpufreq.h>
11 #include <linux/sched/deadline.h>
12 #include <linux/sched.h>
13 #include <linux/sched/loadavg.h>
14 #include <linux/sched/mm.h>
15 #include <linux/sched/rseq_api.h>
16 #include <linux/sched/signal.h>
17 #include <linux/sched/smt.h>
18 #include <linux/sched/stat.h>
19 #include <linux/sched/sysctl.h>
20 #include <linux/sched/task_flags.h>
21 #include <linux/sched/task.h>
22 #include <linux/sched/topology.h>
23 #include <linux/atomic.h>
24 #include <linux/bitmap.h>
25 #include <linux/bug.h>
26 #include <linux/capability.h>
27 #include <linux/cgroup_api.h>
28 #include <linux/cgroup.h>
29 #include <linux/context_tracking.h>
30 #include <linux/cpufreq.h>
31 #include <linux/cpumask_api.h>
32 #include <linux/ctype.h>
33 #include <linux/file.h>
34 #include <linux/fs_api.h>
35 #include <linux/hrtimer_api.h>
36 #include <linux/interrupt.h>
37 #include <linux/irq_work.h>
38 #include <linux/jiffies.h>
39 #include <linux/kref_api.h>
40 #include <linux/kthread.h>
41 #include <linux/ktime_api.h>
42 #include <linux/lockdep_api.h>
43 #include <linux/lockdep.h>
44 #include <linux/minmax.h>
45 #include <linux/mm.h>
46 #include <linux/module.h>
47 #include <linux/mutex_api.h>
48 #include <linux/plist.h>
49 #include <linux/poll.h>
50 #include <linux/proc_fs.h>
51 #include <linux/profile.h>
52 #include <linux/psi.h>
53 #include <linux/rcupdate.h>
54 #include <linux/seq_file.h>
55 #include <linux/seqlock.h>
56 #include <linux/softirq.h>
57 #include <linux/spinlock_api.h>
58 #include <linux/static_key.h>
59 #include <linux/stop_machine.h>
60 #include <linux/syscalls_api.h>
61 #include <linux/syscalls.h>
62 #include <linux/tick.h>
63 #include <linux/topology.h>
64 #include <linux/types.h>
65 #include <linux/u64_stats_sync_api.h>
66 #include <linux/uaccess.h>
67 #include <linux/wait_api.h>
68 #include <linux/wait_bit.h>
69 #include <linux/workqueue_api.h>
70 #include <linux/delayacct.h>
71 #include <linux/mmu_context.h>
72 
73 #include <trace/events/power.h>
74 #include <trace/events/sched.h>
75 
76 #include "../workqueue_internal.h"
77 
78 struct rq;
79 struct cfs_rq;
80 struct rt_rq;
81 struct sched_group;
82 struct cpuidle_state;
83 
84 #ifdef CONFIG_PARAVIRT
85 # include <asm/paravirt.h>
86 # include <asm/paravirt_api_clock.h>
87 #endif
88 
89 #include <asm/barrier.h>
90 
91 #include "cpupri.h"
92 #include "cpudeadline.h"
93 
94 /* task_struct::on_rq states: */
95 #define TASK_ON_RQ_QUEUED	1
96 #define TASK_ON_RQ_MIGRATING	2
97 
98 extern __read_mostly int scheduler_running;
99 
100 extern unsigned long calc_load_update;
101 extern atomic_long_t calc_load_tasks;
102 
103 extern void calc_global_load_tick(struct rq *this_rq);
104 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
105 
106 extern void call_trace_sched_update_nr_running(struct rq *rq, int count);
107 
108 extern int sysctl_sched_rt_period;
109 extern int sysctl_sched_rt_runtime;
110 extern int sched_rr_timeslice;
111 
112 /*
113  * Asymmetric CPU capacity bits
114  */
115 struct asym_cap_data {
116 	struct list_head link;
117 	struct rcu_head rcu;
118 	unsigned long capacity;
119 	unsigned long cpus[];
120 };
121 
122 extern struct list_head asym_cap_list;
123 
124 #define cpu_capacity_span(asym_data) to_cpumask((asym_data)->cpus)
125 
126 /*
127  * Helpers for converting nanosecond timing to jiffy resolution
128  */
129 #define NS_TO_JIFFIES(time)	((unsigned long)(time) / (NSEC_PER_SEC/HZ))
130 
131 /*
132  * Increase resolution of nice-level calculations for 64-bit architectures.
133  * The extra resolution improves shares distribution and load balancing of
134  * low-weight task groups (eg. nice +19 on an autogroup), deeper task-group
135  * hierarchies, especially on larger systems. This is not a user-visible change
136  * and does not change the user-interface for setting shares/weights.
137  *
138  * We increase resolution only if we have enough bits to allow this increased
139  * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
140  * are pretty high and the returns do not justify the increased costs.
141  *
142  * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
143  * increase coverage and consistency always enable it on 64-bit platforms.
144  */
145 #ifdef CONFIG_64BIT
146 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
147 # define scale_load(w)		((w) << SCHED_FIXEDPOINT_SHIFT)
148 # define scale_load_down(w)					\
149 ({								\
150 	unsigned long __w = (w);				\
151 								\
152 	if (__w)						\
153 		__w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT);	\
154 	__w;							\
155 })
156 #else
157 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT)
158 # define scale_load(w)		(w)
159 # define scale_load_down(w)	(w)
160 #endif
161 
162 /*
163  * Task weight (visible to users) and its load (invisible to users) have
164  * independent resolution, but they should be well calibrated. We use
165  * scale_load() and scale_load_down(w) to convert between them. The
166  * following must be true:
167  *
168  *  scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD
169  *
170  */
171 #define NICE_0_LOAD		(1L << NICE_0_LOAD_SHIFT)
172 
173 /*
174  * Single value that decides SCHED_DEADLINE internal math precision.
175  * 10 -> just above 1us
176  * 9  -> just above 0.5us
177  */
178 #define DL_SCALE		10
179 
180 /*
181  * Single value that denotes runtime == period, ie unlimited time.
182  */
183 #define RUNTIME_INF		((u64)~0ULL)
184 
185 static inline int idle_policy(int policy)
186 {
187 	return policy == SCHED_IDLE;
188 }
189 
190 static inline int normal_policy(int policy)
191 {
192 #ifdef CONFIG_SCHED_CLASS_EXT
193 	if (policy == SCHED_EXT)
194 		return true;
195 #endif
196 	return policy == SCHED_NORMAL;
197 }
198 
199 static inline int fair_policy(int policy)
200 {
201 	return normal_policy(policy) || policy == SCHED_BATCH;
202 }
203 
204 static inline int rt_policy(int policy)
205 {
206 	return policy == SCHED_FIFO || policy == SCHED_RR;
207 }
208 
209 static inline int dl_policy(int policy)
210 {
211 	return policy == SCHED_DEADLINE;
212 }
213 
214 static inline bool valid_policy(int policy)
215 {
216 	return idle_policy(policy) || fair_policy(policy) ||
217 		rt_policy(policy) || dl_policy(policy);
218 }
219 
220 static inline int task_has_idle_policy(struct task_struct *p)
221 {
222 	return idle_policy(p->policy);
223 }
224 
225 static inline int task_has_rt_policy(struct task_struct *p)
226 {
227 	return rt_policy(p->policy);
228 }
229 
230 static inline int task_has_dl_policy(struct task_struct *p)
231 {
232 	return dl_policy(p->policy);
233 }
234 
235 #define cap_scale(v, s)		((v)*(s) >> SCHED_CAPACITY_SHIFT)
236 
237 static inline void update_avg(u64 *avg, u64 sample)
238 {
239 	s64 diff = sample - *avg;
240 
241 	*avg += diff / 8;
242 }
243 
244 /*
245  * Shifting a value by an exponent greater *or equal* to the size of said value
246  * is UB; cap at size-1.
247  */
248 #define shr_bound(val, shift)							\
249 	(val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1))
250 
251 /*
252  * cgroup weight knobs should use the common MIN, DFL and MAX values which are
253  * 1, 100 and 10000 respectively. While it loses a bit of range on both ends, it
254  * maps pretty well onto the shares value used by scheduler and the round-trip
255  * conversions preserve the original value over the entire range.
256  */
257 static inline unsigned long sched_weight_from_cgroup(unsigned long cgrp_weight)
258 {
259 	return DIV_ROUND_CLOSEST_ULL(cgrp_weight * 1024, CGROUP_WEIGHT_DFL);
260 }
261 
262 static inline unsigned long sched_weight_to_cgroup(unsigned long weight)
263 {
264 	return clamp_t(unsigned long,
265 		       DIV_ROUND_CLOSEST_ULL(weight * CGROUP_WEIGHT_DFL, 1024),
266 		       CGROUP_WEIGHT_MIN, CGROUP_WEIGHT_MAX);
267 }
268 
269 /*
270  * !! For sched_setattr_nocheck() (kernel) only !!
271  *
272  * This is actually gross. :(
273  *
274  * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
275  * tasks, but still be able to sleep. We need this on platforms that cannot
276  * atomically change clock frequency. Remove once fast switching will be
277  * available on such platforms.
278  *
279  * SUGOV stands for SchedUtil GOVernor.
280  */
281 #define SCHED_FLAG_SUGOV	0x10000000
282 
283 #define SCHED_DL_FLAGS		(SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV)
284 
285 static inline bool dl_entity_is_special(const struct sched_dl_entity *dl_se)
286 {
287 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
288 	return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
289 #else
290 	return false;
291 #endif
292 }
293 
294 /*
295  * Tells if entity @a should preempt entity @b.
296  */
297 static inline bool dl_entity_preempt(const struct sched_dl_entity *a,
298 				     const struct sched_dl_entity *b)
299 {
300 	return dl_entity_is_special(a) ||
301 	       dl_time_before(a->deadline, b->deadline);
302 }
303 
304 /*
305  * This is the priority-queue data structure of the RT scheduling class:
306  */
307 struct rt_prio_array {
308 	DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
309 	struct list_head queue[MAX_RT_PRIO];
310 };
311 
312 struct rt_bandwidth {
313 	/* nests inside the rq lock: */
314 	raw_spinlock_t		rt_runtime_lock;
315 	ktime_t			rt_period;
316 	u64			rt_runtime;
317 	struct hrtimer		rt_period_timer;
318 	unsigned int		rt_period_active;
319 };
320 
321 static inline int dl_bandwidth_enabled(void)
322 {
323 	return sysctl_sched_rt_runtime >= 0;
324 }
325 
326 /*
327  * To keep the bandwidth of -deadline tasks under control
328  * we need some place where:
329  *  - store the maximum -deadline bandwidth of each cpu;
330  *  - cache the fraction of bandwidth that is currently allocated in
331  *    each root domain;
332  *
333  * This is all done in the data structure below. It is similar to the
334  * one used for RT-throttling (rt_bandwidth), with the main difference
335  * that, since here we are only interested in admission control, we
336  * do not decrease any runtime while the group "executes", neither we
337  * need a timer to replenish it.
338  *
339  * With respect to SMP, bandwidth is given on a per root domain basis,
340  * meaning that:
341  *  - bw (< 100%) is the deadline bandwidth of each CPU;
342  *  - total_bw is the currently allocated bandwidth in each root domain;
343  */
344 struct dl_bw {
345 	raw_spinlock_t		lock;
346 	u64			bw;
347 	u64			total_bw;
348 };
349 
350 extern void init_dl_bw(struct dl_bw *dl_b);
351 extern int  sched_dl_global_validate(void);
352 extern void sched_dl_do_global(void);
353 extern int  sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
354 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
355 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
356 extern bool __checkparam_dl(const struct sched_attr *attr);
357 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
358 extern int  dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
359 extern int  dl_bw_deactivate(int cpu);
360 extern s64 dl_scaled_delta_exec(struct rq *rq, struct sched_dl_entity *dl_se, s64 delta_exec);
361 /*
362  * SCHED_DEADLINE supports servers (nested scheduling) with the following
363  * interface:
364  *
365  *   dl_se::rq -- runqueue we belong to.
366  *
367  *   dl_se::server_pick() -- nested pick_next_task(); we yield the period if this
368  *                           returns NULL.
369  *
370  *   dl_server_update() -- called from update_curr_common(), propagates runtime
371  *                         to the server.
372  *
373  *   dl_server_start() -- start the server when it has tasks; it will stop
374  *			  automatically when there are no more tasks, per
375  *			  dl_se::server_pick() returning NULL.
376  *
377  *   dl_server_stop() -- (force) stop the server; use when updating
378  *                       parameters.
379  *
380  *   dl_server_init() -- initializes the server.
381  *
382  * When started the dl_server will (per dl_defer) schedule a timer for its
383  * zero-laxity point -- that is, unlike regular EDF tasks which run ASAP, a
384  * server will run at the very end of its period.
385  *
386  * This is done such that any runtime from the target class can be accounted
387  * against the server -- through dl_server_update() above -- such that when it
388  * becomes time to run, it might already be out of runtime and get deferred
389  * until the next period. In this case dl_server_timer() will alternate
390  * between defer and replenish but never actually enqueue the server.
391  *
392  * Only when the target class does not manage to exhaust the server's runtime
393  * (there's actualy starvation in the given period), will the dl_server get on
394  * the runqueue. Once queued it will pick tasks from the target class and run
395  * them until either its runtime is exhaused, at which point its back to
396  * dl_server_timer, or until there are no more tasks to run, at which point
397  * the dl_server stops itself.
398  *
399  * By stopping at this point the dl_server retains bandwidth, which, if a new
400  * task wakes up imminently (starting the server again), can be used --
401  * subject to CBS wakeup rules -- without having to wait for the next period.
402  *
403  * Additionally, because of the dl_defer behaviour the start/stop behaviour is
404  * naturally thottled to once per period, avoiding high context switch
405  * workloads from spamming the hrtimer program/cancel paths.
406  */
407 extern void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec);
408 extern void dl_server_start(struct sched_dl_entity *dl_se);
409 extern void dl_server_stop(struct sched_dl_entity *dl_se);
410 extern void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq,
411 		    dl_server_pick_f pick_task);
412 extern void sched_init_dl_servers(void);
413 
414 extern void dl_server_update_idle_time(struct rq *rq,
415 		    struct task_struct *p);
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			min_vruntime;
685 #ifdef CONFIG_SCHED_CORE
686 	unsigned int		forceidle_seq;
687 	u64			min_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		kick_sync;
807 	local_t			reenq_local_deferred;
808 	struct balance_callback	deferred_bal_cb;
809 	struct irq_work		deferred_irq_work;
810 	struct irq_work		kick_cpus_irq_work;
811 };
812 #endif /* CONFIG_SCHED_CLASS_EXT */
813 
814 static inline int rt_bandwidth_enabled(void)
815 {
816 	return sysctl_sched_rt_runtime >= 0;
817 }
818 
819 /* RT IPI pull logic requires IRQ_WORK */
820 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
821 # define HAVE_RT_PUSH_IPI
822 #endif
823 
824 /* Real-Time classes' related field in a runqueue: */
825 struct rt_rq {
826 	struct rt_prio_array	active;
827 	unsigned int		rt_nr_running;
828 	unsigned int		rr_nr_running;
829 	struct {
830 		int		curr; /* highest queued rt task prio */
831 		int		next; /* next highest */
832 	} highest_prio;
833 	bool			overloaded;
834 	struct plist_head	pushable_tasks;
835 
836 	int			rt_queued;
837 
838 #ifdef CONFIG_RT_GROUP_SCHED
839 	int			rt_throttled;
840 	u64			rt_time; /* consumed RT time, goes up in update_curr_rt */
841 	u64			rt_runtime; /* allotted RT time, "slice" from rt_bandwidth, RT sharing/balancing */
842 	/* Nests inside the rq lock: */
843 	raw_spinlock_t		rt_runtime_lock;
844 
845 	unsigned int		rt_nr_boosted;
846 
847 	struct rq		*rq; /* this is always top-level rq, cache? */
848 #endif
849 #ifdef CONFIG_CGROUP_SCHED
850 	struct task_group	*tg; /* this tg has "this" rt_rq on given CPU for runnable entities */
851 #endif
852 };
853 
854 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
855 {
856 	return rt_rq->rt_queued && rt_rq->rt_nr_running;
857 }
858 
859 /* Deadline class' related fields in a runqueue */
860 struct dl_rq {
861 	/* runqueue is an rbtree, ordered by deadline */
862 	struct rb_root_cached	root;
863 
864 	unsigned int		dl_nr_running;
865 
866 	/*
867 	 * Deadline values of the currently executing and the
868 	 * earliest ready task on this rq. Caching these facilitates
869 	 * the decision whether or not a ready but not running task
870 	 * should migrate somewhere else.
871 	 */
872 	struct {
873 		u64		curr;
874 		u64		next;
875 	} earliest_dl;
876 
877 	bool			overloaded;
878 
879 	/*
880 	 * Tasks on this rq that can be pushed away. They are kept in
881 	 * an rb-tree, ordered by tasks' deadlines, with caching
882 	 * of the leftmost (earliest deadline) element.
883 	 */
884 	struct rb_root_cached	pushable_dl_tasks_root;
885 
886 	/*
887 	 * "Active utilization" for this runqueue: increased when a
888 	 * task wakes up (becomes TASK_RUNNING) and decreased when a
889 	 * task blocks
890 	 */
891 	u64			running_bw;
892 
893 	/*
894 	 * Utilization of the tasks "assigned" to this runqueue (including
895 	 * the tasks that are in runqueue and the tasks that executed on this
896 	 * CPU and blocked). Increased when a task moves to this runqueue, and
897 	 * decreased when the task moves away (migrates, changes scheduling
898 	 * policy, or terminates).
899 	 * This is needed to compute the "inactive utilization" for the
900 	 * runqueue (inactive utilization = this_bw - running_bw).
901 	 */
902 	u64			this_bw;
903 	u64			extra_bw;
904 
905 	/*
906 	 * Maximum available bandwidth for reclaiming by SCHED_FLAG_RECLAIM
907 	 * tasks of this rq. Used in calculation of reclaimable bandwidth(GRUB).
908 	 */
909 	u64			max_bw;
910 
911 	/*
912 	 * Inverse of the fraction of CPU utilization that can be reclaimed
913 	 * by the GRUB algorithm.
914 	 */
915 	u64			bw_ratio;
916 };
917 
918 #ifdef CONFIG_FAIR_GROUP_SCHED
919 
920 /* An entity is a task if it doesn't "own" a runqueue */
921 #define entity_is_task(se)	(!se->my_q)
922 
923 static inline void se_update_runnable(struct sched_entity *se)
924 {
925 	if (!entity_is_task(se))
926 		se->runnable_weight = se->my_q->h_nr_runnable;
927 }
928 
929 static inline long se_runnable(struct sched_entity *se)
930 {
931 	if (se->sched_delayed)
932 		return false;
933 
934 	if (entity_is_task(se))
935 		return !!se->on_rq;
936 	else
937 		return se->runnable_weight;
938 }
939 
940 #else /* !CONFIG_FAIR_GROUP_SCHED: */
941 
942 #define entity_is_task(se)	1
943 
944 static inline void se_update_runnable(struct sched_entity *se) { }
945 
946 static inline long se_runnable(struct sched_entity *se)
947 {
948 	if (se->sched_delayed)
949 		return false;
950 
951 	return !!se->on_rq;
952 }
953 
954 #endif /* !CONFIG_FAIR_GROUP_SCHED */
955 
956 /*
957  * XXX we want to get rid of these helpers and use the full load resolution.
958  */
959 static inline long se_weight(struct sched_entity *se)
960 {
961 	return scale_load_down(se->load.weight);
962 }
963 
964 
965 static inline bool sched_asym_prefer(int a, int b)
966 {
967 	return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
968 }
969 
970 struct perf_domain {
971 	struct em_perf_domain *em_pd;
972 	struct perf_domain *next;
973 	struct rcu_head rcu;
974 };
975 
976 /*
977  * We add the notion of a root-domain which will be used to define per-domain
978  * variables. Each exclusive cpuset essentially defines an island domain by
979  * fully partitioning the member CPUs from any other cpuset. Whenever a new
980  * exclusive cpuset is created, we also create and attach a new root-domain
981  * object.
982  *
983  */
984 struct root_domain {
985 	atomic_t		refcount;
986 	atomic_t		rto_count;
987 	struct rcu_head		rcu;
988 	cpumask_var_t		span;
989 	cpumask_var_t		online;
990 
991 	/*
992 	 * Indicate pullable load on at least one CPU, e.g:
993 	 * - More than one runnable task
994 	 * - Running task is misfit
995 	 */
996 	bool			overloaded;
997 
998 	/* Indicate one or more CPUs over-utilized (tipping point) */
999 	bool			overutilized;
1000 
1001 	/*
1002 	 * The bit corresponding to a CPU gets set here if such CPU has more
1003 	 * than one runnable -deadline task (as it is below for RT tasks).
1004 	 */
1005 	cpumask_var_t		dlo_mask;
1006 	atomic_t		dlo_count;
1007 	struct dl_bw		dl_bw;
1008 	struct cpudl		cpudl;
1009 
1010 	/*
1011 	 * Indicate whether a root_domain's dl_bw has been checked or
1012 	 * updated. It's monotonously increasing value.
1013 	 *
1014 	 * Also, some corner cases, like 'wrap around' is dangerous, but given
1015 	 * that u64 is 'big enough'. So that shouldn't be a concern.
1016 	 */
1017 	u64 visit_cookie;
1018 
1019 #ifdef HAVE_RT_PUSH_IPI
1020 	/*
1021 	 * For IPI pull requests, loop across the rto_mask.
1022 	 */
1023 	struct irq_work		rto_push_work;
1024 	raw_spinlock_t		rto_lock;
1025 	/* These are only updated and read within rto_lock */
1026 	int			rto_loop;
1027 	int			rto_cpu;
1028 	/* These atomics are updated outside of a lock */
1029 	atomic_t		rto_loop_next;
1030 	atomic_t		rto_loop_start;
1031 #endif /* HAVE_RT_PUSH_IPI */
1032 	/*
1033 	 * The "RT overload" flag: it gets set if a CPU has more than
1034 	 * one runnable RT task.
1035 	 */
1036 	cpumask_var_t		rto_mask;
1037 	struct cpupri		cpupri;
1038 
1039 	/*
1040 	 * NULL-terminated list of performance domains intersecting with the
1041 	 * CPUs of the rd. Protected by RCU.
1042 	 */
1043 	struct perf_domain __rcu *pd;
1044 };
1045 
1046 extern void init_defrootdomain(void);
1047 extern int sched_init_domains(const struct cpumask *cpu_map);
1048 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
1049 extern void sched_get_rd(struct root_domain *rd);
1050 extern void sched_put_rd(struct root_domain *rd);
1051 
1052 static inline int get_rd_overloaded(struct root_domain *rd)
1053 {
1054 	return READ_ONCE(rd->overloaded);
1055 }
1056 
1057 static inline void set_rd_overloaded(struct root_domain *rd, int status)
1058 {
1059 	if (get_rd_overloaded(rd) != status)
1060 		WRITE_ONCE(rd->overloaded, status);
1061 }
1062 
1063 #ifdef HAVE_RT_PUSH_IPI
1064 extern void rto_push_irq_work_func(struct irq_work *work);
1065 #endif
1066 
1067 #ifdef CONFIG_UCLAMP_TASK
1068 /*
1069  * struct uclamp_bucket - Utilization clamp bucket
1070  * @value: utilization clamp value for tasks on this clamp bucket
1071  * @tasks: number of RUNNABLE tasks on this clamp bucket
1072  *
1073  * Keep track of how many tasks are RUNNABLE for a given utilization
1074  * clamp value.
1075  */
1076 struct uclamp_bucket {
1077 	unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
1078 	unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
1079 };
1080 
1081 /*
1082  * struct uclamp_rq - rq's utilization clamp
1083  * @value: currently active clamp values for a rq
1084  * @bucket: utilization clamp buckets affecting a rq
1085  *
1086  * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
1087  * A clamp value is affecting a rq when there is at least one task RUNNABLE
1088  * (or actually running) with that value.
1089  *
1090  * There are up to UCLAMP_CNT possible different clamp values, currently there
1091  * are only two: minimum utilization and maximum utilization.
1092  *
1093  * All utilization clamping values are MAX aggregated, since:
1094  * - for util_min: we want to run the CPU at least at the max of the minimum
1095  *   utilization required by its currently RUNNABLE tasks.
1096  * - for util_max: we want to allow the CPU to run up to the max of the
1097  *   maximum utilization allowed by its currently RUNNABLE tasks.
1098  *
1099  * Since on each system we expect only a limited number of different
1100  * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
1101  * the metrics required to compute all the per-rq utilization clamp values.
1102  */
1103 struct uclamp_rq {
1104 	unsigned int value;
1105 	struct uclamp_bucket bucket[UCLAMP_BUCKETS];
1106 };
1107 
1108 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
1109 #endif /* CONFIG_UCLAMP_TASK */
1110 
1111 /*
1112  * This is the main, per-CPU runqueue data structure.
1113  *
1114  * Locking rule: those places that want to lock multiple runqueues
1115  * (such as the load balancing or the thread migration code), lock
1116  * acquire operations must be ordered by ascending &runqueue.
1117  */
1118 struct rq {
1119 	/* runqueue lock: */
1120 	raw_spinlock_t		__lock;
1121 
1122 	/* Per class runqueue modification mask; bits in class order. */
1123 	unsigned int		queue_mask;
1124 	unsigned int		nr_running;
1125 #ifdef CONFIG_NUMA_BALANCING
1126 	unsigned int		nr_numa_running;
1127 	unsigned int		nr_preferred_running;
1128 	unsigned int		numa_migrate_on;
1129 #endif
1130 #ifdef CONFIG_NO_HZ_COMMON
1131 	unsigned long		last_blocked_load_update_tick;
1132 	unsigned int		has_blocked_load;
1133 	call_single_data_t	nohz_csd;
1134 	unsigned int		nohz_tick_stopped;
1135 	atomic_t		nohz_flags;
1136 #endif /* CONFIG_NO_HZ_COMMON */
1137 
1138 	unsigned int		ttwu_pending;
1139 	u64			nr_switches;
1140 
1141 #ifdef CONFIG_UCLAMP_TASK
1142 	/* Utilization clamp values based on CPU's RUNNABLE tasks */
1143 	struct uclamp_rq	uclamp[UCLAMP_CNT] ____cacheline_aligned;
1144 	unsigned int		uclamp_flags;
1145 #define UCLAMP_FLAG_IDLE 0x01
1146 #endif
1147 
1148 	struct cfs_rq		cfs;
1149 	struct rt_rq		rt;
1150 	struct dl_rq		dl;
1151 #ifdef CONFIG_SCHED_CLASS_EXT
1152 	struct scx_rq		scx;
1153 #endif
1154 
1155 	struct sched_dl_entity	fair_server;
1156 
1157 #ifdef CONFIG_FAIR_GROUP_SCHED
1158 	/* list of leaf cfs_rq on this CPU: */
1159 	struct list_head	leaf_cfs_rq_list;
1160 	struct list_head	*tmp_alone_branch;
1161 #endif /* CONFIG_FAIR_GROUP_SCHED */
1162 
1163 	/*
1164 	 * This is part of a global counter where only the total sum
1165 	 * over all CPUs matters. A task can increase this counter on
1166 	 * one CPU and if it got migrated afterwards it may decrease
1167 	 * it on another CPU. Always updated under the runqueue lock:
1168 	 */
1169 	unsigned long 		nr_uninterruptible;
1170 
1171 #ifdef CONFIG_SCHED_PROXY_EXEC
1172 	struct task_struct __rcu	*donor;  /* Scheduling context */
1173 	struct task_struct __rcu	*curr;   /* Execution context */
1174 #else
1175 	union {
1176 		struct task_struct __rcu *donor; /* Scheduler context */
1177 		struct task_struct __rcu *curr;  /* Execution context */
1178 	};
1179 #endif
1180 	struct sched_dl_entity	*dl_server;
1181 	struct task_struct	*idle;
1182 	struct task_struct	*stop;
1183 	unsigned long		next_balance;
1184 	struct mm_struct	*prev_mm;
1185 
1186 	unsigned int		clock_update_flags;
1187 	u64			clock;
1188 	/* Ensure that all clocks are in the same cache line */
1189 	u64			clock_task ____cacheline_aligned;
1190 	u64			clock_pelt;
1191 	unsigned long		lost_idle_time;
1192 	u64			clock_pelt_idle;
1193 	u64			clock_idle;
1194 #ifndef CONFIG_64BIT
1195 	u64			clock_pelt_idle_copy;
1196 	u64			clock_idle_copy;
1197 #endif
1198 
1199 	atomic_t		nr_iowait;
1200 
1201 	u64 last_seen_need_resched_ns;
1202 	int ticks_without_resched;
1203 
1204 #ifdef CONFIG_MEMBARRIER
1205 	int membarrier_state;
1206 #endif
1207 
1208 	struct root_domain		*rd;
1209 	struct sched_domain __rcu	*sd;
1210 
1211 	unsigned long		cpu_capacity;
1212 
1213 	struct balance_callback *balance_callback;
1214 
1215 	unsigned char		nohz_idle_balance;
1216 	unsigned char		idle_balance;
1217 
1218 	unsigned long		misfit_task_load;
1219 
1220 	/* For active balancing */
1221 	int			active_balance;
1222 	int			push_cpu;
1223 	struct cpu_stop_work	active_balance_work;
1224 
1225 	/* CPU of this runqueue: */
1226 	int			cpu;
1227 	int			online;
1228 
1229 	struct list_head cfs_tasks;
1230 
1231 	struct sched_avg	avg_rt;
1232 	struct sched_avg	avg_dl;
1233 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1234 	struct sched_avg	avg_irq;
1235 #endif
1236 #ifdef CONFIG_SCHED_HW_PRESSURE
1237 	struct sched_avg	avg_hw;
1238 #endif
1239 	u64			idle_stamp;
1240 	u64			avg_idle;
1241 
1242 	/* This is used to determine avg_idle's max value */
1243 	u64			max_idle_balance_cost;
1244 
1245 #ifdef CONFIG_HOTPLUG_CPU
1246 	struct rcuwait		hotplug_wait;
1247 #endif
1248 
1249 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1250 	u64			prev_irq_time;
1251 	u64			psi_irq_time;
1252 #endif
1253 #ifdef CONFIG_PARAVIRT
1254 	u64			prev_steal_time;
1255 #endif
1256 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1257 	u64			prev_steal_time_rq;
1258 #endif
1259 
1260 	/* calc_load related fields */
1261 	unsigned long		calc_load_update;
1262 	long			calc_load_active;
1263 
1264 #ifdef CONFIG_SCHED_HRTICK
1265 	call_single_data_t	hrtick_csd;
1266 	struct hrtimer		hrtick_timer;
1267 	ktime_t			hrtick_time;
1268 #endif
1269 
1270 #ifdef CONFIG_SCHEDSTATS
1271 	/* latency stats */
1272 	struct sched_info	rq_sched_info;
1273 	unsigned long long	rq_cpu_time;
1274 
1275 	/* sys_sched_yield() stats */
1276 	unsigned int		yld_count;
1277 
1278 	/* schedule() stats */
1279 	unsigned int		sched_count;
1280 	unsigned int		sched_goidle;
1281 
1282 	/* try_to_wake_up() stats */
1283 	unsigned int		ttwu_count;
1284 	unsigned int		ttwu_local;
1285 #endif
1286 
1287 #ifdef CONFIG_CPU_IDLE
1288 	/* Must be inspected within a RCU lock section */
1289 	struct cpuidle_state	*idle_state;
1290 #endif
1291 
1292 	unsigned int		nr_pinned;
1293 	unsigned int		push_busy;
1294 	struct cpu_stop_work	push_work;
1295 
1296 #ifdef CONFIG_SCHED_CORE
1297 	/* per rq */
1298 	struct rq		*core;
1299 	struct task_struct	*core_pick;
1300 	struct sched_dl_entity	*core_dl_server;
1301 	unsigned int		core_enabled;
1302 	unsigned int		core_sched_seq;
1303 	struct rb_root		core_tree;
1304 
1305 	/* shared state -- careful with sched_core_cpu_deactivate() */
1306 	unsigned int		core_task_seq;
1307 	unsigned int		core_pick_seq;
1308 	unsigned long		core_cookie;
1309 	unsigned int		core_forceidle_count;
1310 	unsigned int		core_forceidle_seq;
1311 	unsigned int		core_forceidle_occupation;
1312 	u64			core_forceidle_start;
1313 #endif /* CONFIG_SCHED_CORE */
1314 
1315 	/* Scratch cpumask to be temporarily used under rq_lock */
1316 	cpumask_var_t		scratch_mask;
1317 
1318 #ifdef CONFIG_CFS_BANDWIDTH
1319 	call_single_data_t	cfsb_csd;
1320 	struct list_head	cfsb_csd_list;
1321 #endif
1322 };
1323 
1324 #ifdef CONFIG_FAIR_GROUP_SCHED
1325 
1326 /* CPU runqueue to which this cfs_rq is attached */
1327 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1328 {
1329 	return cfs_rq->rq;
1330 }
1331 
1332 #else /* !CONFIG_FAIR_GROUP_SCHED: */
1333 
1334 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1335 {
1336 	return container_of(cfs_rq, struct rq, cfs);
1337 }
1338 #endif /* !CONFIG_FAIR_GROUP_SCHED */
1339 
1340 static inline int cpu_of(struct rq *rq)
1341 {
1342 	return rq->cpu;
1343 }
1344 
1345 #define MDF_PUSH		0x01
1346 
1347 static inline bool is_migration_disabled(struct task_struct *p)
1348 {
1349 	return p->migration_disabled;
1350 }
1351 
1352 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1353 
1354 #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
1355 #define this_rq()		this_cpu_ptr(&runqueues)
1356 #define task_rq(p)		cpu_rq(task_cpu(p))
1357 #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
1358 #define raw_rq()		raw_cpu_ptr(&runqueues)
1359 
1360 #ifdef CONFIG_SCHED_PROXY_EXEC
1361 static inline void rq_set_donor(struct rq *rq, struct task_struct *t)
1362 {
1363 	rcu_assign_pointer(rq->donor, t);
1364 }
1365 #else
1366 static inline void rq_set_donor(struct rq *rq, struct task_struct *t)
1367 {
1368 	/* Do nothing */
1369 }
1370 #endif
1371 
1372 #ifdef CONFIG_SCHED_CORE
1373 static inline struct cpumask *sched_group_span(struct sched_group *sg);
1374 
1375 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled);
1376 
1377 static inline bool sched_core_enabled(struct rq *rq)
1378 {
1379 	return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled;
1380 }
1381 
1382 static inline bool sched_core_disabled(void)
1383 {
1384 	return !static_branch_unlikely(&__sched_core_enabled);
1385 }
1386 
1387 /*
1388  * Be careful with this function; not for general use. The return value isn't
1389  * stable unless you actually hold a relevant rq->__lock.
1390  */
1391 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1392 {
1393 	if (sched_core_enabled(rq))
1394 		return &rq->core->__lock;
1395 
1396 	return &rq->__lock;
1397 }
1398 
1399 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1400 {
1401 	if (rq->core_enabled)
1402 		return &rq->core->__lock;
1403 
1404 	return &rq->__lock;
1405 }
1406 
1407 extern bool
1408 cfs_prio_less(const struct task_struct *a, const struct task_struct *b, bool fi);
1409 
1410 extern void task_vruntime_update(struct rq *rq, struct task_struct *p, bool in_fi);
1411 
1412 /*
1413  * Helpers to check if the CPU's core cookie matches with the task's cookie
1414  * when core scheduling is enabled.
1415  * A special case is that the task's cookie always matches with CPU's core
1416  * cookie if the CPU is in an idle core.
1417  */
1418 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1419 {
1420 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1421 	if (!sched_core_enabled(rq))
1422 		return true;
1423 
1424 	return rq->core->core_cookie == p->core_cookie;
1425 }
1426 
1427 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1428 {
1429 	bool idle_core = true;
1430 	int cpu;
1431 
1432 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1433 	if (!sched_core_enabled(rq))
1434 		return true;
1435 
1436 	for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) {
1437 		if (!available_idle_cpu(cpu)) {
1438 			idle_core = false;
1439 			break;
1440 		}
1441 	}
1442 
1443 	/*
1444 	 * A CPU in an idle core is always the best choice for tasks with
1445 	 * cookies.
1446 	 */
1447 	return idle_core || rq->core->core_cookie == p->core_cookie;
1448 }
1449 
1450 static inline bool sched_group_cookie_match(struct rq *rq,
1451 					    struct task_struct *p,
1452 					    struct sched_group *group)
1453 {
1454 	int cpu;
1455 
1456 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1457 	if (!sched_core_enabled(rq))
1458 		return true;
1459 
1460 	for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
1461 		if (sched_core_cookie_match(cpu_rq(cpu), p))
1462 			return true;
1463 	}
1464 	return false;
1465 }
1466 
1467 static inline bool sched_core_enqueued(struct task_struct *p)
1468 {
1469 	return !RB_EMPTY_NODE(&p->core_node);
1470 }
1471 
1472 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p);
1473 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags);
1474 
1475 extern void sched_core_get(void);
1476 extern void sched_core_put(void);
1477 
1478 #else /* !CONFIG_SCHED_CORE: */
1479 
1480 static inline bool sched_core_enabled(struct rq *rq)
1481 {
1482 	return false;
1483 }
1484 
1485 static inline bool sched_core_disabled(void)
1486 {
1487 	return true;
1488 }
1489 
1490 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1491 {
1492 	return &rq->__lock;
1493 }
1494 
1495 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1496 {
1497 	return &rq->__lock;
1498 }
1499 
1500 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1501 {
1502 	return true;
1503 }
1504 
1505 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1506 {
1507 	return true;
1508 }
1509 
1510 static inline bool sched_group_cookie_match(struct rq *rq,
1511 					    struct task_struct *p,
1512 					    struct sched_group *group)
1513 {
1514 	return true;
1515 }
1516 
1517 #endif /* !CONFIG_SCHED_CORE */
1518 
1519 #ifdef CONFIG_RT_GROUP_SCHED
1520 # ifdef CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED
1521 DECLARE_STATIC_KEY_FALSE(rt_group_sched);
1522 static inline bool rt_group_sched_enabled(void)
1523 {
1524 	return static_branch_unlikely(&rt_group_sched);
1525 }
1526 # else /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED: */
1527 DECLARE_STATIC_KEY_TRUE(rt_group_sched);
1528 static inline bool rt_group_sched_enabled(void)
1529 {
1530 	return static_branch_likely(&rt_group_sched);
1531 }
1532 # endif /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED */
1533 #else /* !CONFIG_RT_GROUP_SCHED: */
1534 # define rt_group_sched_enabled()	false
1535 #endif /* !CONFIG_RT_GROUP_SCHED */
1536 
1537 static inline void lockdep_assert_rq_held(struct rq *rq)
1538 {
1539 	lockdep_assert_held(__rq_lockp(rq));
1540 }
1541 
1542 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass);
1543 extern bool raw_spin_rq_trylock(struct rq *rq);
1544 extern void raw_spin_rq_unlock(struct rq *rq);
1545 
1546 static inline void raw_spin_rq_lock(struct rq *rq)
1547 {
1548 	raw_spin_rq_lock_nested(rq, 0);
1549 }
1550 
1551 static inline void raw_spin_rq_lock_irq(struct rq *rq)
1552 {
1553 	local_irq_disable();
1554 	raw_spin_rq_lock(rq);
1555 }
1556 
1557 static inline void raw_spin_rq_unlock_irq(struct rq *rq)
1558 {
1559 	raw_spin_rq_unlock(rq);
1560 	local_irq_enable();
1561 }
1562 
1563 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq)
1564 {
1565 	unsigned long flags;
1566 
1567 	local_irq_save(flags);
1568 	raw_spin_rq_lock(rq);
1569 
1570 	return flags;
1571 }
1572 
1573 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags)
1574 {
1575 	raw_spin_rq_unlock(rq);
1576 	local_irq_restore(flags);
1577 }
1578 
1579 #define raw_spin_rq_lock_irqsave(rq, flags)	\
1580 do {						\
1581 	flags = _raw_spin_rq_lock_irqsave(rq);	\
1582 } while (0)
1583 
1584 #ifdef CONFIG_SCHED_SMT
1585 extern void __update_idle_core(struct rq *rq);
1586 
1587 static inline void update_idle_core(struct rq *rq)
1588 {
1589 	if (static_branch_unlikely(&sched_smt_present))
1590 		__update_idle_core(rq);
1591 }
1592 
1593 #else /* !CONFIG_SCHED_SMT: */
1594 static inline void update_idle_core(struct rq *rq) { }
1595 #endif /* !CONFIG_SCHED_SMT */
1596 
1597 #ifdef CONFIG_FAIR_GROUP_SCHED
1598 
1599 static inline struct task_struct *task_of(struct sched_entity *se)
1600 {
1601 	WARN_ON_ONCE(!entity_is_task(se));
1602 	return container_of(se, struct task_struct, se);
1603 }
1604 
1605 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1606 {
1607 	return p->se.cfs_rq;
1608 }
1609 
1610 /* runqueue on which this entity is (to be) queued */
1611 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1612 {
1613 	return se->cfs_rq;
1614 }
1615 
1616 /* runqueue "owned" by this group */
1617 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1618 {
1619 	return grp->my_q;
1620 }
1621 
1622 #else /* !CONFIG_FAIR_GROUP_SCHED: */
1623 
1624 #define task_of(_se)		container_of(_se, struct task_struct, se)
1625 
1626 static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p)
1627 {
1628 	return &task_rq(p)->cfs;
1629 }
1630 
1631 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1632 {
1633 	const struct task_struct *p = task_of(se);
1634 	struct rq *rq = task_rq(p);
1635 
1636 	return &rq->cfs;
1637 }
1638 
1639 /* runqueue "owned" by this group */
1640 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1641 {
1642 	return NULL;
1643 }
1644 
1645 #endif /* !CONFIG_FAIR_GROUP_SCHED */
1646 
1647 extern void update_rq_clock(struct rq *rq);
1648 
1649 /*
1650  * rq::clock_update_flags bits
1651  *
1652  * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1653  *  call to __schedule(). This is an optimisation to avoid
1654  *  neighbouring rq clock updates.
1655  *
1656  * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1657  *  in effect and calls to update_rq_clock() are being ignored.
1658  *
1659  * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1660  *  made to update_rq_clock() since the last time rq::lock was pinned.
1661  *
1662  * If inside of __schedule(), clock_update_flags will have been
1663  * shifted left (a left shift is a cheap operation for the fast path
1664  * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1665  *
1666  *	if (rq-clock_update_flags >= RQCF_UPDATED)
1667  *
1668  * to check if %RQCF_UPDATED is set. It'll never be shifted more than
1669  * one position though, because the next rq_unpin_lock() will shift it
1670  * back.
1671  */
1672 #define RQCF_REQ_SKIP		0x01
1673 #define RQCF_ACT_SKIP		0x02
1674 #define RQCF_UPDATED		0x04
1675 
1676 static inline void assert_clock_updated(struct rq *rq)
1677 {
1678 	/*
1679 	 * The only reason for not seeing a clock update since the
1680 	 * last rq_pin_lock() is if we're currently skipping updates.
1681 	 */
1682 	WARN_ON_ONCE(rq->clock_update_flags < RQCF_ACT_SKIP);
1683 }
1684 
1685 static inline u64 rq_clock(struct rq *rq)
1686 {
1687 	lockdep_assert_rq_held(rq);
1688 	assert_clock_updated(rq);
1689 
1690 	return rq->clock;
1691 }
1692 
1693 static inline u64 rq_clock_task(struct rq *rq)
1694 {
1695 	lockdep_assert_rq_held(rq);
1696 	assert_clock_updated(rq);
1697 
1698 	return rq->clock_task;
1699 }
1700 
1701 static inline void rq_clock_skip_update(struct rq *rq)
1702 {
1703 	lockdep_assert_rq_held(rq);
1704 	rq->clock_update_flags |= RQCF_REQ_SKIP;
1705 }
1706 
1707 /*
1708  * See rt task throttling, which is the only time a skip
1709  * request is canceled.
1710  */
1711 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1712 {
1713 	lockdep_assert_rq_held(rq);
1714 	rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1715 }
1716 
1717 /*
1718  * During cpu offlining and rq wide unthrottling, we can trigger
1719  * an update_rq_clock() for several cfs and rt runqueues (Typically
1720  * when using list_for_each_entry_*)
1721  * rq_clock_start_loop_update() can be called after updating the clock
1722  * once and before iterating over the list to prevent multiple update.
1723  * After the iterative traversal, we need to call rq_clock_stop_loop_update()
1724  * to clear RQCF_ACT_SKIP of rq->clock_update_flags.
1725  */
1726 static inline void rq_clock_start_loop_update(struct rq *rq)
1727 {
1728 	lockdep_assert_rq_held(rq);
1729 	WARN_ON_ONCE(rq->clock_update_flags & RQCF_ACT_SKIP);
1730 	rq->clock_update_flags |= RQCF_ACT_SKIP;
1731 }
1732 
1733 static inline void rq_clock_stop_loop_update(struct rq *rq)
1734 {
1735 	lockdep_assert_rq_held(rq);
1736 	rq->clock_update_flags &= ~RQCF_ACT_SKIP;
1737 }
1738 
1739 struct rq_flags {
1740 	unsigned long flags;
1741 	struct pin_cookie cookie;
1742 	/*
1743 	 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1744 	 * current pin context is stashed here in case it needs to be
1745 	 * restored in rq_repin_lock().
1746 	 */
1747 	unsigned int clock_update_flags;
1748 };
1749 
1750 extern struct balance_callback balance_push_callback;
1751 
1752 #ifdef CONFIG_SCHED_CLASS_EXT
1753 extern const struct sched_class ext_sched_class;
1754 
1755 DECLARE_STATIC_KEY_FALSE(__scx_enabled);	/* SCX BPF scheduler loaded */
1756 DECLARE_STATIC_KEY_FALSE(__scx_switched_all);	/* all fair class tasks on SCX */
1757 
1758 #define scx_enabled()		static_branch_unlikely(&__scx_enabled)
1759 #define scx_switched_all()	static_branch_unlikely(&__scx_switched_all)
1760 
1761 static inline void scx_rq_clock_update(struct rq *rq, u64 clock)
1762 {
1763 	if (!scx_enabled())
1764 		return;
1765 	WRITE_ONCE(rq->scx.clock, clock);
1766 	smp_store_release(&rq->scx.flags, rq->scx.flags | SCX_RQ_CLK_VALID);
1767 }
1768 
1769 static inline void scx_rq_clock_invalidate(struct rq *rq)
1770 {
1771 	if (!scx_enabled())
1772 		return;
1773 	WRITE_ONCE(rq->scx.flags, rq->scx.flags & ~SCX_RQ_CLK_VALID);
1774 }
1775 
1776 #else /* !CONFIG_SCHED_CLASS_EXT: */
1777 #define scx_enabled()		false
1778 #define scx_switched_all()	false
1779 
1780 static inline void scx_rq_clock_update(struct rq *rq, u64 clock) {}
1781 static inline void scx_rq_clock_invalidate(struct rq *rq) {}
1782 #endif /* !CONFIG_SCHED_CLASS_EXT */
1783 
1784 /*
1785  * Lockdep annotation that avoids accidental unlocks; it's like a
1786  * sticky/continuous lockdep_assert_held().
1787  *
1788  * This avoids code that has access to 'struct rq *rq' (basically everything in
1789  * the scheduler) from accidentally unlocking the rq if they do not also have a
1790  * copy of the (on-stack) 'struct rq_flags rf'.
1791  *
1792  * Also see Documentation/locking/lockdep-design.rst.
1793  */
1794 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1795 {
1796 	rf->cookie = lockdep_pin_lock(__rq_lockp(rq));
1797 
1798 	rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1799 	rf->clock_update_flags = 0;
1800 	WARN_ON_ONCE(rq->balance_callback && rq->balance_callback != &balance_push_callback);
1801 }
1802 
1803 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1804 {
1805 	if (rq->clock_update_flags > RQCF_ACT_SKIP)
1806 		rf->clock_update_flags = RQCF_UPDATED;
1807 
1808 	scx_rq_clock_invalidate(rq);
1809 	lockdep_unpin_lock(__rq_lockp(rq), rf->cookie);
1810 }
1811 
1812 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1813 {
1814 	lockdep_repin_lock(__rq_lockp(rq), rf->cookie);
1815 
1816 	/*
1817 	 * Restore the value we stashed in @rf for this pin context.
1818 	 */
1819 	rq->clock_update_flags |= rf->clock_update_flags;
1820 }
1821 
1822 extern
1823 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1824 	__acquires(rq->lock);
1825 
1826 extern
1827 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1828 	__acquires(p->pi_lock)
1829 	__acquires(rq->lock);
1830 
1831 static inline void
1832 __task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1833 	__releases(rq->lock)
1834 {
1835 	rq_unpin_lock(rq, rf);
1836 	raw_spin_rq_unlock(rq);
1837 }
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 	__releases(p->pi_lock)
1843 {
1844 	__task_rq_unlock(rq, p, rf);
1845 	raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1846 }
1847 
1848 DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct,
1849 		    _T->rq = task_rq_lock(_T->lock, &_T->rf),
1850 		    task_rq_unlock(_T->rq, _T->lock, &_T->rf),
1851 		    struct rq *rq; struct rq_flags rf)
1852 
1853 DEFINE_LOCK_GUARD_1(__task_rq_lock, struct task_struct,
1854 		    _T->rq = __task_rq_lock(_T->lock, &_T->rf),
1855 		    __task_rq_unlock(_T->rq, _T->lock, &_T->rf),
1856 		    struct rq *rq; struct rq_flags rf)
1857 
1858 static inline void rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1859 	__acquires(rq->lock)
1860 {
1861 	raw_spin_rq_lock_irqsave(rq, rf->flags);
1862 	rq_pin_lock(rq, rf);
1863 }
1864 
1865 static inline void rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1866 	__acquires(rq->lock)
1867 {
1868 	raw_spin_rq_lock_irq(rq);
1869 	rq_pin_lock(rq, rf);
1870 }
1871 
1872 static inline void rq_lock(struct rq *rq, struct rq_flags *rf)
1873 	__acquires(rq->lock)
1874 {
1875 	raw_spin_rq_lock(rq);
1876 	rq_pin_lock(rq, rf);
1877 }
1878 
1879 static inline void rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1880 	__releases(rq->lock)
1881 {
1882 	rq_unpin_lock(rq, rf);
1883 	raw_spin_rq_unlock_irqrestore(rq, rf->flags);
1884 }
1885 
1886 static inline void rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1887 	__releases(rq->lock)
1888 {
1889 	rq_unpin_lock(rq, rf);
1890 	raw_spin_rq_unlock_irq(rq);
1891 }
1892 
1893 static inline void rq_unlock(struct rq *rq, struct rq_flags *rf)
1894 	__releases(rq->lock)
1895 {
1896 	rq_unpin_lock(rq, rf);
1897 	raw_spin_rq_unlock(rq);
1898 }
1899 
1900 DEFINE_LOCK_GUARD_1(rq_lock, struct rq,
1901 		    rq_lock(_T->lock, &_T->rf),
1902 		    rq_unlock(_T->lock, &_T->rf),
1903 		    struct rq_flags rf)
1904 
1905 DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq,
1906 		    rq_lock_irq(_T->lock, &_T->rf),
1907 		    rq_unlock_irq(_T->lock, &_T->rf),
1908 		    struct rq_flags rf)
1909 
1910 DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq,
1911 		    rq_lock_irqsave(_T->lock, &_T->rf),
1912 		    rq_unlock_irqrestore(_T->lock, &_T->rf),
1913 		    struct rq_flags rf)
1914 
1915 static inline struct rq *this_rq_lock_irq(struct rq_flags *rf)
1916 	__acquires(rq->lock)
1917 {
1918 	struct rq *rq;
1919 
1920 	local_irq_disable();
1921 	rq = this_rq();
1922 	rq_lock(rq, rf);
1923 
1924 	return rq;
1925 }
1926 
1927 #ifdef CONFIG_NUMA
1928 
1929 enum numa_topology_type {
1930 	NUMA_DIRECT,
1931 	NUMA_GLUELESS_MESH,
1932 	NUMA_BACKPLANE,
1933 };
1934 
1935 extern enum numa_topology_type sched_numa_topology_type;
1936 extern int sched_max_numa_distance;
1937 extern bool find_numa_distance(int distance);
1938 extern void sched_init_numa(int offline_node);
1939 extern void sched_update_numa(int cpu, bool online);
1940 extern void sched_domains_numa_masks_set(unsigned int cpu);
1941 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1942 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1943 
1944 #else /* !CONFIG_NUMA: */
1945 
1946 static inline void sched_init_numa(int offline_node) { }
1947 static inline void sched_update_numa(int cpu, bool online) { }
1948 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
1949 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1950 
1951 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1952 {
1953 	return nr_cpu_ids;
1954 }
1955 
1956 #endif /* !CONFIG_NUMA */
1957 
1958 #ifdef CONFIG_NUMA_BALANCING
1959 
1960 /* The regions in numa_faults array from task_struct */
1961 enum numa_faults_stats {
1962 	NUMA_MEM = 0,
1963 	NUMA_CPU,
1964 	NUMA_MEMBUF,
1965 	NUMA_CPUBUF
1966 };
1967 
1968 extern void sched_setnuma(struct task_struct *p, int node);
1969 extern int migrate_task_to(struct task_struct *p, int cpu);
1970 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1971 			int cpu, int scpu);
1972 extern void init_numa_balancing(u64 clone_flags, struct task_struct *p);
1973 
1974 #else /* !CONFIG_NUMA_BALANCING: */
1975 
1976 static inline void
1977 init_numa_balancing(u64 clone_flags, struct task_struct *p)
1978 {
1979 }
1980 
1981 #endif /* !CONFIG_NUMA_BALANCING */
1982 
1983 static inline void
1984 queue_balance_callback(struct rq *rq,
1985 		       struct balance_callback *head,
1986 		       void (*func)(struct rq *rq))
1987 {
1988 	lockdep_assert_rq_held(rq);
1989 
1990 	/*
1991 	 * Don't (re)queue an already queued item; nor queue anything when
1992 	 * balance_push() is active, see the comment with
1993 	 * balance_push_callback.
1994 	 */
1995 	if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
1996 		return;
1997 
1998 	head->func = func;
1999 	head->next = rq->balance_callback;
2000 	rq->balance_callback = head;
2001 }
2002 
2003 #define rcu_dereference_check_sched_domain(p) \
2004 	rcu_dereference_check((p), lockdep_is_held(&sched_domains_mutex))
2005 
2006 /*
2007  * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
2008  * See destroy_sched_domains: call_rcu for details.
2009  *
2010  * The domain tree of any CPU may only be accessed from within
2011  * preempt-disabled sections.
2012  */
2013 #define for_each_domain(cpu, __sd) \
2014 	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
2015 			__sd; __sd = __sd->parent)
2016 
2017 /* A mask of all the SD flags that have the SDF_SHARED_CHILD metaflag */
2018 #define SD_FLAG(name, mflags) (name * !!((mflags) & SDF_SHARED_CHILD)) |
2019 static const unsigned int SD_SHARED_CHILD_MASK =
2020 #include <linux/sched/sd_flags.h>
2021 0;
2022 #undef SD_FLAG
2023 
2024 /**
2025  * highest_flag_domain - Return highest sched_domain containing flag.
2026  * @cpu:	The CPU whose highest level of sched domain is to
2027  *		be returned.
2028  * @flag:	The flag to check for the highest sched_domain
2029  *		for the given CPU.
2030  *
2031  * Returns the highest sched_domain of a CPU which contains @flag. If @flag has
2032  * the SDF_SHARED_CHILD metaflag, all the children domains also have @flag.
2033  */
2034 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
2035 {
2036 	struct sched_domain *sd, *hsd = NULL;
2037 
2038 	for_each_domain(cpu, sd) {
2039 		if (sd->flags & flag) {
2040 			hsd = sd;
2041 			continue;
2042 		}
2043 
2044 		/*
2045 		 * Stop the search if @flag is known to be shared at lower
2046 		 * levels. It will not be found further up.
2047 		 */
2048 		if (flag & SD_SHARED_CHILD_MASK)
2049 			break;
2050 	}
2051 
2052 	return hsd;
2053 }
2054 
2055 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
2056 {
2057 	struct sched_domain *sd;
2058 
2059 	for_each_domain(cpu, sd) {
2060 		if (sd->flags & flag)
2061 			break;
2062 	}
2063 
2064 	return sd;
2065 }
2066 
2067 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
2068 DECLARE_PER_CPU(int, sd_llc_size);
2069 DECLARE_PER_CPU(int, sd_llc_id);
2070 DECLARE_PER_CPU(int, sd_share_id);
2071 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
2072 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
2073 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
2074 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
2075 
2076 extern struct static_key_false sched_asym_cpucapacity;
2077 extern struct static_key_false sched_cluster_active;
2078 
2079 static __always_inline bool sched_asym_cpucap_active(void)
2080 {
2081 	return static_branch_unlikely(&sched_asym_cpucapacity);
2082 }
2083 
2084 struct sched_group_capacity {
2085 	atomic_t		ref;
2086 	/*
2087 	 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
2088 	 * for a single CPU.
2089 	 */
2090 	unsigned long		capacity;
2091 	unsigned long		min_capacity;		/* Min per-CPU capacity in group */
2092 	unsigned long		max_capacity;		/* Max per-CPU capacity in group */
2093 	unsigned long		next_update;
2094 	int			imbalance;		/* XXX unrelated to capacity but shared group state */
2095 
2096 	int			id;
2097 
2098 	unsigned long		cpumask[];		/* Balance mask */
2099 };
2100 
2101 struct sched_group {
2102 	struct sched_group	*next;			/* Must be a circular list */
2103 	atomic_t		ref;
2104 
2105 	unsigned int		group_weight;
2106 	unsigned int		cores;
2107 	struct sched_group_capacity *sgc;
2108 	int			asym_prefer_cpu;	/* CPU of highest priority in group */
2109 	int			flags;
2110 
2111 	/*
2112 	 * The CPUs this group covers.
2113 	 *
2114 	 * NOTE: this field is variable length. (Allocated dynamically
2115 	 * by attaching extra space to the end of the structure,
2116 	 * depending on how many CPUs the kernel has booted up with)
2117 	 */
2118 	unsigned long		cpumask[];
2119 };
2120 
2121 static inline struct cpumask *sched_group_span(struct sched_group *sg)
2122 {
2123 	return to_cpumask(sg->cpumask);
2124 }
2125 
2126 /*
2127  * See build_balance_mask().
2128  */
2129 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
2130 {
2131 	return to_cpumask(sg->sgc->cpumask);
2132 }
2133 
2134 extern int group_balance_cpu(struct sched_group *sg);
2135 
2136 extern void update_sched_domain_debugfs(void);
2137 extern void dirty_sched_domain_sysctl(int cpu);
2138 
2139 extern int sched_update_scaling(void);
2140 
2141 static inline const struct cpumask *task_user_cpus(struct task_struct *p)
2142 {
2143 	if (!p->user_cpus_ptr)
2144 		return cpu_possible_mask; /* &init_task.cpus_mask */
2145 	return p->user_cpus_ptr;
2146 }
2147 
2148 #ifdef CONFIG_CGROUP_SCHED
2149 
2150 /*
2151  * Return the group to which this tasks belongs.
2152  *
2153  * We cannot use task_css() and friends because the cgroup subsystem
2154  * changes that value before the cgroup_subsys::attach() method is called,
2155  * therefore we cannot pin it and might observe the wrong value.
2156  *
2157  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
2158  * core changes this before calling sched_move_task().
2159  *
2160  * Instead we use a 'copy' which is updated from sched_move_task() while
2161  * holding both task_struct::pi_lock and rq::lock.
2162  */
2163 static inline struct task_group *task_group(struct task_struct *p)
2164 {
2165 	return p->sched_task_group;
2166 }
2167 
2168 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
2169 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
2170 {
2171 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
2172 	struct task_group *tg = task_group(p);
2173 #endif
2174 
2175 #ifdef CONFIG_FAIR_GROUP_SCHED
2176 	set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
2177 	p->se.cfs_rq = tg->cfs_rq[cpu];
2178 	p->se.parent = tg->se[cpu];
2179 	p->se.depth = tg->se[cpu] ? tg->se[cpu]->depth + 1 : 0;
2180 #endif
2181 
2182 #ifdef CONFIG_RT_GROUP_SCHED
2183 	/*
2184 	 * p->rt.rt_rq is NULL initially and it is easier to assign
2185 	 * root_task_group's rt_rq than switching in rt_rq_of_se()
2186 	 * Clobbers tg(!)
2187 	 */
2188 	if (!rt_group_sched_enabled())
2189 		tg = &root_task_group;
2190 	p->rt.rt_rq  = tg->rt_rq[cpu];
2191 	p->rt.parent = tg->rt_se[cpu];
2192 #endif /* CONFIG_RT_GROUP_SCHED */
2193 }
2194 
2195 #else /* !CONFIG_CGROUP_SCHED: */
2196 
2197 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
2198 
2199 static inline struct task_group *task_group(struct task_struct *p)
2200 {
2201 	return NULL;
2202 }
2203 
2204 #endif /* !CONFIG_CGROUP_SCHED */
2205 
2206 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
2207 {
2208 	set_task_rq(p, cpu);
2209 #ifdef CONFIG_SMP
2210 	/*
2211 	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
2212 	 * successfully executed on another CPU. We must ensure that updates of
2213 	 * per-task data have been completed by this moment.
2214 	 */
2215 	smp_wmb();
2216 	WRITE_ONCE(task_thread_info(p)->cpu, cpu);
2217 	p->wake_cpu = cpu;
2218 #endif /* CONFIG_SMP */
2219 }
2220 
2221 /*
2222  * Tunables:
2223  */
2224 
2225 #define SCHED_FEAT(name, enabled)	\
2226 	__SCHED_FEAT_##name ,
2227 
2228 enum {
2229 #include "features.h"
2230 	__SCHED_FEAT_NR,
2231 };
2232 
2233 #undef SCHED_FEAT
2234 
2235 /*
2236  * To support run-time toggling of sched features, all the translation units
2237  * (but core.c) reference the sysctl_sched_features defined in core.c.
2238  */
2239 extern __read_mostly unsigned int sysctl_sched_features;
2240 
2241 #ifdef CONFIG_JUMP_LABEL
2242 
2243 #define SCHED_FEAT(name, enabled)					\
2244 static __always_inline bool static_branch_##name(struct static_key *key) \
2245 {									\
2246 	return static_key_##enabled(key);				\
2247 }
2248 
2249 #include "features.h"
2250 #undef SCHED_FEAT
2251 
2252 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
2253 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
2254 
2255 #else /* !CONFIG_JUMP_LABEL: */
2256 
2257 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2258 
2259 #endif /* !CONFIG_JUMP_LABEL */
2260 
2261 extern struct static_key_false sched_numa_balancing;
2262 extern struct static_key_false sched_schedstats;
2263 
2264 static inline u64 global_rt_period(void)
2265 {
2266 	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
2267 }
2268 
2269 static inline u64 global_rt_runtime(void)
2270 {
2271 	if (sysctl_sched_rt_runtime < 0)
2272 		return RUNTIME_INF;
2273 
2274 	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
2275 }
2276 
2277 /*
2278  * Is p the current execution context?
2279  */
2280 static inline int task_current(struct rq *rq, struct task_struct *p)
2281 {
2282 	return rq->curr == p;
2283 }
2284 
2285 /*
2286  * Is p the current scheduling context?
2287  *
2288  * Note that it might be the current execution context at the same time if
2289  * rq->curr == rq->donor == p.
2290  */
2291 static inline int task_current_donor(struct rq *rq, struct task_struct *p)
2292 {
2293 	return rq->donor == p;
2294 }
2295 
2296 static inline bool task_is_blocked(struct task_struct *p)
2297 {
2298 	if (!sched_proxy_exec())
2299 		return false;
2300 
2301 	return !!p->blocked_on;
2302 }
2303 
2304 static inline int task_on_cpu(struct rq *rq, struct task_struct *p)
2305 {
2306 	return p->on_cpu;
2307 }
2308 
2309 static inline int task_on_rq_queued(struct task_struct *p)
2310 {
2311 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_QUEUED;
2312 }
2313 
2314 static inline int task_on_rq_migrating(struct task_struct *p)
2315 {
2316 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
2317 }
2318 
2319 /* Wake flags. The first three directly map to some SD flag value */
2320 #define WF_EXEC			0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
2321 #define WF_FORK			0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
2322 #define WF_TTWU			0x08 /* Wakeup;            maps to SD_BALANCE_WAKE */
2323 
2324 #define WF_SYNC			0x10 /* Waker goes to sleep after wakeup */
2325 #define WF_MIGRATED		0x20 /* Internal use, task got migrated */
2326 #define WF_CURRENT_CPU		0x40 /* Prefer to move the wakee to the current CPU. */
2327 #define WF_RQ_SELECTED		0x80 /* ->select_task_rq() was called */
2328 
2329 static_assert(WF_EXEC == SD_BALANCE_EXEC);
2330 static_assert(WF_FORK == SD_BALANCE_FORK);
2331 static_assert(WF_TTWU == SD_BALANCE_WAKE);
2332 
2333 /*
2334  * To aid in avoiding the subversion of "niceness" due to uneven distribution
2335  * of tasks with abnormal "nice" values across CPUs the contribution that
2336  * each task makes to its run queue's load is weighted according to its
2337  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
2338  * scaled version of the new time slice allocation that they receive on time
2339  * slice expiry etc.
2340  */
2341 
2342 #define WEIGHT_IDLEPRIO		3
2343 #define WMULT_IDLEPRIO		1431655765
2344 
2345 extern const int		sched_prio_to_weight[40];
2346 extern const u32		sched_prio_to_wmult[40];
2347 
2348 /*
2349  * {de,en}queue flags:
2350  *
2351  * SLEEP/WAKEUP - task is no-longer/just-became runnable
2352  *
2353  * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
2354  *                are in a known state which allows modification. Such pairs
2355  *                should preserve as much state as possible.
2356  *
2357  * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
2358  *        in the runqueue.
2359  *
2360  * NOCLOCK - skip the update_rq_clock() (avoids double updates)
2361  *
2362  * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE)
2363  *
2364  * DELAYED - de/re-queue a sched_delayed task
2365  *
2366  * CLASS - going to update p->sched_class; makes sched_change call the
2367  *         various switch methods.
2368  *
2369  * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
2370  * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
2371  * ENQUEUE_MIGRATED  - the task was migrated during wakeup
2372  * ENQUEUE_RQ_SELECTED - ->select_task_rq() was called
2373  *
2374  * XXX SAVE/RESTORE in combination with CLASS doesn't really make sense, but
2375  * SCHED_DEADLINE seems to rely on this for now.
2376  */
2377 
2378 #define DEQUEUE_SLEEP		0x0001 /* Matches ENQUEUE_WAKEUP */
2379 #define DEQUEUE_SAVE		0x0002 /* Matches ENQUEUE_RESTORE */
2380 #define DEQUEUE_MOVE		0x0004 /* Matches ENQUEUE_MOVE */
2381 #define DEQUEUE_NOCLOCK		0x0008 /* Matches ENQUEUE_NOCLOCK */
2382 
2383 #define DEQUEUE_MIGRATING	0x0010 /* Matches ENQUEUE_MIGRATING */
2384 #define DEQUEUE_DELAYED		0x0020 /* Matches ENQUEUE_DELAYED */
2385 #define DEQUEUE_CLASS		0x0040 /* Matches ENQUEUE_CLASS */
2386 
2387 #define DEQUEUE_SPECIAL		0x00010000
2388 #define DEQUEUE_THROTTLE	0x00020000
2389 
2390 #define ENQUEUE_WAKEUP		0x0001
2391 #define ENQUEUE_RESTORE		0x0002
2392 #define ENQUEUE_MOVE		0x0004
2393 #define ENQUEUE_NOCLOCK		0x0008
2394 
2395 #define ENQUEUE_MIGRATING	0x0010
2396 #define ENQUEUE_DELAYED		0x0020
2397 #define ENQUEUE_CLASS		0x0040
2398 
2399 #define ENQUEUE_HEAD		0x00010000
2400 #define ENQUEUE_REPLENISH	0x00020000
2401 #define ENQUEUE_MIGRATED	0x00040000
2402 #define ENQUEUE_INITIAL		0x00080000
2403 #define ENQUEUE_RQ_SELECTED	0x00100000
2404 
2405 #define RETRY_TASK		((void *)-1UL)
2406 
2407 struct affinity_context {
2408 	const struct cpumask	*new_mask;
2409 	struct cpumask		*user_mask;
2410 	unsigned int		flags;
2411 };
2412 
2413 extern s64 update_curr_common(struct rq *rq);
2414 
2415 struct sched_class {
2416 
2417 #ifdef CONFIG_UCLAMP_TASK
2418 	int uclamp_enabled;
2419 #endif
2420 	/*
2421 	 * idle:  0
2422 	 * ext:   1
2423 	 * fair:  2
2424 	 * rt:    4
2425 	 * dl:    8
2426 	 * stop: 16
2427 	 */
2428 	unsigned int queue_mask;
2429 
2430 	/*
2431 	 * move_queued_task/activate_task/enqueue_task: rq->lock
2432 	 * ttwu_do_activate/activate_task/enqueue_task: rq->lock
2433 	 * wake_up_new_task/activate_task/enqueue_task: task_rq_lock
2434 	 * ttwu_runnable/enqueue_task: task_rq_lock
2435 	 * proxy_task_current: rq->lock
2436 	 * sched_change_end
2437 	 */
2438 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
2439 	/*
2440 	 * move_queued_task/deactivate_task/dequeue_task: rq->lock
2441 	 * __schedule/block_task/dequeue_task: rq->lock
2442 	 * proxy_task_current: rq->lock
2443 	 * wait_task_inactive: task_rq_lock
2444 	 * sched_change_begin
2445 	 */
2446 	bool (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
2447 
2448 	/*
2449 	 * do_sched_yield: rq->lock
2450 	 */
2451 	void (*yield_task)   (struct rq *rq);
2452 	/*
2453 	 * yield_to: rq->lock (double)
2454 	 */
2455 	bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
2456 
2457 	/*
2458 	 * move_queued_task: rq->lock
2459 	 * __migrate_swap_task: rq->lock
2460 	 * ttwu_do_activate: rq->lock
2461 	 * ttwu_runnable: task_rq_lock
2462 	 * wake_up_new_task: task_rq_lock
2463 	 */
2464 	void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags);
2465 
2466 	/*
2467 	 * schedule/pick_next_task/prev_balance: rq->lock
2468 	 */
2469 	int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2470 
2471 	/*
2472 	 * schedule/pick_next_task: rq->lock
2473 	 */
2474 	struct task_struct *(*pick_task)(struct rq *rq, struct rq_flags *rf);
2475 	/*
2476 	 * Optional! When implemented pick_next_task() should be equivalent to:
2477 	 *
2478 	 *   next = pick_task();
2479 	 *   if (next) {
2480 	 *       put_prev_task(prev);
2481 	 *       set_next_task_first(next);
2482 	 *   }
2483 	 */
2484 	struct task_struct *(*pick_next_task)(struct rq *rq, struct task_struct *prev,
2485 					      struct rq_flags *rf);
2486 
2487 	/*
2488 	 * sched_change:
2489 	 * __schedule: rq->lock
2490 	 */
2491 	void (*put_prev_task)(struct rq *rq, struct task_struct *p, struct task_struct *next);
2492 	void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
2493 
2494 	/*
2495 	 * select_task_rq: p->pi_lock
2496 	 * sched_exec: p->pi_lock
2497 	 */
2498 	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
2499 
2500 	/*
2501 	 * set_task_cpu: p->pi_lock || rq->lock (ttwu like)
2502 	 */
2503 	void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
2504 
2505 	/*
2506 	 * ttwu_do_activate: rq->lock
2507 	 * wake_up_new_task: task_rq_lock
2508 	 */
2509 	void (*task_woken)(struct rq *this_rq, struct task_struct *task);
2510 
2511 	/*
2512 	 * do_set_cpus_allowed: task_rq_lock + sched_change
2513 	 */
2514 	void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx);
2515 
2516 	/*
2517 	 * sched_set_rq_{on,off}line: rq->lock
2518 	 */
2519 	void (*rq_online)(struct rq *rq);
2520 	void (*rq_offline)(struct rq *rq);
2521 
2522 	/*
2523 	 * push_cpu_stop: p->pi_lock && rq->lock
2524 	 */
2525 	struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
2526 
2527 	/*
2528 	 * hrtick: rq->lock
2529 	 * sched_tick: rq->lock
2530 	 * sched_tick_remote: rq->lock
2531 	 */
2532 	void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
2533 	/*
2534 	 * sched_cgroup_fork: p->pi_lock
2535 	 */
2536 	void (*task_fork)(struct task_struct *p);
2537 	/*
2538 	 * finish_task_switch: no locks
2539 	 */
2540 	void (*task_dead)(struct task_struct *p);
2541 
2542 	/*
2543 	 * sched_change
2544 	 */
2545 	void (*switching_from)(struct rq *this_rq, struct task_struct *task);
2546 	void (*switched_from) (struct rq *this_rq, struct task_struct *task);
2547 	void (*switching_to)  (struct rq *this_rq, struct task_struct *task);
2548 	void (*switched_to)   (struct rq *this_rq, struct task_struct *task);
2549 	u64  (*get_prio)     (struct rq *this_rq, struct task_struct *task);
2550 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
2551 			      u64 oldprio);
2552 
2553 	/*
2554 	 * set_load_weight: task_rq_lock + sched_change
2555 	 * __setscheduler_parms: task_rq_lock + sched_change
2556 	 */
2557 	void (*reweight_task)(struct rq *this_rq, struct task_struct *task,
2558 			      const struct load_weight *lw);
2559 
2560 	/*
2561 	 * sched_rr_get_interval: task_rq_lock
2562 	 */
2563 	unsigned int (*get_rr_interval)(struct rq *rq,
2564 					struct task_struct *task);
2565 
2566 	/*
2567 	 * task_sched_runtime: task_rq_lock
2568 	 */
2569 	void (*update_curr)(struct rq *rq);
2570 
2571 #ifdef CONFIG_FAIR_GROUP_SCHED
2572 	/*
2573 	 * sched_change_group: task_rq_lock + sched_change
2574 	 */
2575 	void (*task_change_group)(struct task_struct *p);
2576 #endif
2577 
2578 #ifdef CONFIG_SCHED_CORE
2579 	/*
2580 	 * pick_next_task: rq->lock
2581 	 * try_steal_cookie: rq->lock (double)
2582 	 */
2583 	int (*task_is_throttled)(struct task_struct *p, int cpu);
2584 #endif
2585 };
2586 
2587 /*
2588  * Does not nest; only used around sched_class::pick_task() rq-lock-breaks.
2589  */
2590 static inline void rq_modified_clear(struct rq *rq)
2591 {
2592 	rq->queue_mask = 0;
2593 }
2594 
2595 static inline bool rq_modified_above(struct rq *rq, const struct sched_class * class)
2596 {
2597 	unsigned int mask = class->queue_mask;
2598 	return rq->queue_mask & ~((mask << 1) - 1);
2599 }
2600 
2601 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
2602 {
2603 	WARN_ON_ONCE(rq->donor != prev);
2604 	prev->sched_class->put_prev_task(rq, prev, NULL);
2605 }
2606 
2607 static inline void set_next_task(struct rq *rq, struct task_struct *next)
2608 {
2609 	next->sched_class->set_next_task(rq, next, false);
2610 }
2611 
2612 static inline void
2613 __put_prev_set_next_dl_server(struct rq *rq,
2614 			      struct task_struct *prev,
2615 			      struct task_struct *next)
2616 {
2617 	prev->dl_server = NULL;
2618 	next->dl_server = rq->dl_server;
2619 	rq->dl_server = NULL;
2620 }
2621 
2622 static inline void put_prev_set_next_task(struct rq *rq,
2623 					  struct task_struct *prev,
2624 					  struct task_struct *next)
2625 {
2626 	WARN_ON_ONCE(rq->donor != prev);
2627 
2628 	__put_prev_set_next_dl_server(rq, prev, next);
2629 
2630 	if (next == prev)
2631 		return;
2632 
2633 	prev->sched_class->put_prev_task(rq, prev, next);
2634 	next->sched_class->set_next_task(rq, next, true);
2635 }
2636 
2637 /*
2638  * Helper to define a sched_class instance; each one is placed in a separate
2639  * section which is ordered by the linker script:
2640  *
2641  *   include/asm-generic/vmlinux.lds.h
2642  *
2643  * *CAREFUL* they are laid out in *REVERSE* order!!!
2644  *
2645  * Also enforce alignment on the instance, not the type, to guarantee layout.
2646  */
2647 #define DEFINE_SCHED_CLASS(name) \
2648 const struct sched_class name##_sched_class \
2649 	__aligned(__alignof__(struct sched_class)) \
2650 	__section("__" #name "_sched_class")
2651 
2652 /* Defined in include/asm-generic/vmlinux.lds.h */
2653 extern struct sched_class __sched_class_highest[];
2654 extern struct sched_class __sched_class_lowest[];
2655 
2656 extern const struct sched_class stop_sched_class;
2657 extern const struct sched_class dl_sched_class;
2658 extern const struct sched_class rt_sched_class;
2659 extern const struct sched_class fair_sched_class;
2660 extern const struct sched_class idle_sched_class;
2661 
2662 /*
2663  * Iterate only active classes. SCX can take over all fair tasks or be
2664  * completely disabled. If the former, skip fair. If the latter, skip SCX.
2665  */
2666 static inline const struct sched_class *next_active_class(const struct sched_class *class)
2667 {
2668 	class++;
2669 #ifdef CONFIG_SCHED_CLASS_EXT
2670 	if (scx_switched_all() && class == &fair_sched_class)
2671 		class++;
2672 	if (!scx_enabled() && class == &ext_sched_class)
2673 		class++;
2674 #endif
2675 	return class;
2676 }
2677 
2678 #define for_class_range(class, _from, _to) \
2679 	for (class = (_from); class < (_to); class++)
2680 
2681 #define for_each_class(class) \
2682 	for_class_range(class, __sched_class_highest, __sched_class_lowest)
2683 
2684 #define for_active_class_range(class, _from, _to)				\
2685 	for (class = (_from); class != (_to); class = next_active_class(class))
2686 
2687 #define for_each_active_class(class)						\
2688 	for_active_class_range(class, __sched_class_highest, __sched_class_lowest)
2689 
2690 #define sched_class_above(_a, _b)	((_a) < (_b))
2691 
2692 static inline bool sched_stop_runnable(struct rq *rq)
2693 {
2694 	return rq->stop && task_on_rq_queued(rq->stop);
2695 }
2696 
2697 static inline bool sched_dl_runnable(struct rq *rq)
2698 {
2699 	return rq->dl.dl_nr_running > 0;
2700 }
2701 
2702 static inline bool sched_rt_runnable(struct rq *rq)
2703 {
2704 	return rq->rt.rt_queued > 0;
2705 }
2706 
2707 static inline bool sched_fair_runnable(struct rq *rq)
2708 {
2709 	return rq->cfs.nr_queued > 0;
2710 }
2711 
2712 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev,
2713 					       struct rq_flags *rf);
2714 extern struct task_struct *pick_task_idle(struct rq *rq, struct rq_flags *rf);
2715 
2716 #define SCA_CHECK		0x01
2717 #define SCA_MIGRATE_DISABLE	0x02
2718 #define SCA_MIGRATE_ENABLE	0x04
2719 #define SCA_USER		0x08
2720 
2721 extern void update_group_capacity(struct sched_domain *sd, int cpu);
2722 
2723 extern void sched_balance_trigger(struct rq *rq);
2724 
2725 extern int __set_cpus_allowed_ptr(struct task_struct *p, struct affinity_context *ctx);
2726 extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx);
2727 
2728 static inline bool task_allowed_on_cpu(struct task_struct *p, int cpu)
2729 {
2730 	/* When not in the task's cpumask, no point in looking further. */
2731 	if (!cpumask_test_cpu(cpu, p->cpus_ptr))
2732 		return false;
2733 
2734 	/* Can @cpu run a user thread? */
2735 	if (!(p->flags & PF_KTHREAD) && !task_cpu_possible(cpu, p))
2736 		return false;
2737 
2738 	return true;
2739 }
2740 
2741 static inline cpumask_t *alloc_user_cpus_ptr(int node)
2742 {
2743 	/*
2744 	 * See set_cpus_allowed_force() above for the rcu_head usage.
2745 	 */
2746 	int size = max_t(int, cpumask_size(), sizeof(struct rcu_head));
2747 
2748 	return kmalloc_node(size, GFP_KERNEL, node);
2749 }
2750 
2751 static inline struct task_struct *get_push_task(struct rq *rq)
2752 {
2753 	struct task_struct *p = rq->donor;
2754 
2755 	lockdep_assert_rq_held(rq);
2756 
2757 	if (rq->push_busy)
2758 		return NULL;
2759 
2760 	if (p->nr_cpus_allowed == 1)
2761 		return NULL;
2762 
2763 	if (p->migration_disabled)
2764 		return NULL;
2765 
2766 	rq->push_busy = true;
2767 	return get_task_struct(p);
2768 }
2769 
2770 extern int push_cpu_stop(void *arg);
2771 
2772 #ifdef CONFIG_CPU_IDLE
2773 
2774 static inline void idle_set_state(struct rq *rq,
2775 				  struct cpuidle_state *idle_state)
2776 {
2777 	rq->idle_state = idle_state;
2778 }
2779 
2780 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2781 {
2782 	WARN_ON_ONCE(!rcu_read_lock_held());
2783 
2784 	return rq->idle_state;
2785 }
2786 
2787 #else /* !CONFIG_CPU_IDLE: */
2788 
2789 static inline void idle_set_state(struct rq *rq,
2790 				  struct cpuidle_state *idle_state)
2791 {
2792 }
2793 
2794 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2795 {
2796 	return NULL;
2797 }
2798 
2799 #endif /* !CONFIG_CPU_IDLE */
2800 
2801 extern void schedule_idle(void);
2802 asmlinkage void schedule_user(void);
2803 
2804 extern void sysrq_sched_debug_show(void);
2805 extern void sched_init_granularity(void);
2806 extern void update_max_interval(void);
2807 
2808 extern void init_sched_dl_class(void);
2809 extern void init_sched_rt_class(void);
2810 extern void init_sched_fair_class(void);
2811 
2812 extern void resched_curr(struct rq *rq);
2813 extern void resched_curr_lazy(struct rq *rq);
2814 extern void resched_cpu(int cpu);
2815 
2816 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
2817 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq);
2818 
2819 extern void init_dl_entity(struct sched_dl_entity *dl_se);
2820 
2821 extern void init_cfs_throttle_work(struct task_struct *p);
2822 
2823 #define BW_SHIFT		20
2824 #define BW_UNIT			(1 << BW_SHIFT)
2825 #define RATIO_SHIFT		8
2826 #define MAX_BW_BITS		(64 - BW_SHIFT)
2827 #define MAX_BW			((1ULL << MAX_BW_BITS) - 1)
2828 
2829 extern unsigned long to_ratio(u64 period, u64 runtime);
2830 
2831 extern void init_entity_runnable_average(struct sched_entity *se);
2832 extern void post_init_entity_util_avg(struct task_struct *p);
2833 
2834 #ifdef CONFIG_NO_HZ_FULL
2835 extern bool sched_can_stop_tick(struct rq *rq);
2836 extern int __init sched_tick_offload_init(void);
2837 
2838 /*
2839  * Tick may be needed by tasks in the runqueue depending on their policy and
2840  * requirements. If tick is needed, lets send the target an IPI to kick it out of
2841  * nohz mode if necessary.
2842  */
2843 static inline void sched_update_tick_dependency(struct rq *rq)
2844 {
2845 	int cpu = cpu_of(rq);
2846 
2847 	if (!tick_nohz_full_cpu(cpu))
2848 		return;
2849 
2850 	if (sched_can_stop_tick(rq))
2851 		tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
2852 	else
2853 		tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
2854 }
2855 #else /* !CONFIG_NO_HZ_FULL: */
2856 static inline int sched_tick_offload_init(void) { return 0; }
2857 static inline void sched_update_tick_dependency(struct rq *rq) { }
2858 #endif /* !CONFIG_NO_HZ_FULL */
2859 
2860 static inline void add_nr_running(struct rq *rq, unsigned count)
2861 {
2862 	unsigned prev_nr = rq->nr_running;
2863 
2864 	rq->nr_running = prev_nr + count;
2865 	if (trace_sched_update_nr_running_tp_enabled()) {
2866 		call_trace_sched_update_nr_running(rq, count);
2867 	}
2868 
2869 	if (prev_nr < 2 && rq->nr_running >= 2)
2870 		set_rd_overloaded(rq->rd, 1);
2871 
2872 	sched_update_tick_dependency(rq);
2873 }
2874 
2875 static inline void sub_nr_running(struct rq *rq, unsigned count)
2876 {
2877 	rq->nr_running -= count;
2878 	if (trace_sched_update_nr_running_tp_enabled()) {
2879 		call_trace_sched_update_nr_running(rq, -count);
2880 	}
2881 
2882 	/* Check if we still need preemption */
2883 	sched_update_tick_dependency(rq);
2884 }
2885 
2886 static inline void __block_task(struct rq *rq, struct task_struct *p)
2887 {
2888 	if (p->sched_contributes_to_load)
2889 		rq->nr_uninterruptible++;
2890 
2891 	if (p->in_iowait) {
2892 		atomic_inc(&rq->nr_iowait);
2893 		delayacct_blkio_start();
2894 	}
2895 
2896 	ASSERT_EXCLUSIVE_WRITER(p->on_rq);
2897 
2898 	/*
2899 	 * The moment this write goes through, ttwu() can swoop in and migrate
2900 	 * this task, rendering our rq->__lock ineffective.
2901 	 *
2902 	 * __schedule()				try_to_wake_up()
2903 	 *   LOCK rq->__lock			  LOCK p->pi_lock
2904 	 *   pick_next_task()
2905 	 *     pick_next_task_fair()
2906 	 *       pick_next_entity()
2907 	 *         dequeue_entities()
2908 	 *           __block_task()
2909 	 *             RELEASE p->on_rq = 0	  if (p->on_rq && ...)
2910 	 *					    break;
2911 	 *
2912 	 *					  ACQUIRE (after ctrl-dep)
2913 	 *
2914 	 *					  cpu = select_task_rq();
2915 	 *					  set_task_cpu(p, cpu);
2916 	 *					  ttwu_queue()
2917 	 *					    ttwu_do_activate()
2918 	 *					      LOCK rq->__lock
2919 	 *					      activate_task()
2920 	 *					        STORE p->on_rq = 1
2921 	 *   UNLOCK rq->__lock
2922 	 *
2923 	 * Callers must ensure to not reference @p after this -- we no longer
2924 	 * own it.
2925 	 */
2926 	smp_store_release(&p->on_rq, 0);
2927 }
2928 
2929 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
2930 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
2931 
2932 extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags);
2933 
2934 #ifdef CONFIG_PREEMPT_RT
2935 # define SCHED_NR_MIGRATE_BREAK 8
2936 #else
2937 # define SCHED_NR_MIGRATE_BREAK 32
2938 #endif
2939 
2940 extern __read_mostly unsigned int sysctl_sched_nr_migrate;
2941 extern __read_mostly unsigned int sysctl_sched_migration_cost;
2942 
2943 extern unsigned int sysctl_sched_base_slice;
2944 
2945 extern int sysctl_resched_latency_warn_ms;
2946 extern int sysctl_resched_latency_warn_once;
2947 
2948 extern unsigned int sysctl_sched_tunable_scaling;
2949 
2950 extern unsigned int sysctl_numa_balancing_scan_delay;
2951 extern unsigned int sysctl_numa_balancing_scan_period_min;
2952 extern unsigned int sysctl_numa_balancing_scan_period_max;
2953 extern unsigned int sysctl_numa_balancing_scan_size;
2954 extern unsigned int sysctl_numa_balancing_hot_threshold;
2955 
2956 #ifdef CONFIG_SCHED_HRTICK
2957 
2958 /*
2959  * Use hrtick when:
2960  *  - enabled by features
2961  *  - hrtimer is actually high res
2962  */
2963 static inline int hrtick_enabled(struct rq *rq)
2964 {
2965 	if (!cpu_active(cpu_of(rq)))
2966 		return 0;
2967 	return hrtimer_is_hres_active(&rq->hrtick_timer);
2968 }
2969 
2970 static inline int hrtick_enabled_fair(struct rq *rq)
2971 {
2972 	if (!sched_feat(HRTICK))
2973 		return 0;
2974 	return hrtick_enabled(rq);
2975 }
2976 
2977 static inline int hrtick_enabled_dl(struct rq *rq)
2978 {
2979 	if (!sched_feat(HRTICK_DL))
2980 		return 0;
2981 	return hrtick_enabled(rq);
2982 }
2983 
2984 extern void hrtick_start(struct rq *rq, u64 delay);
2985 
2986 #else /* !CONFIG_SCHED_HRTICK: */
2987 
2988 static inline int hrtick_enabled_fair(struct rq *rq)
2989 {
2990 	return 0;
2991 }
2992 
2993 static inline int hrtick_enabled_dl(struct rq *rq)
2994 {
2995 	return 0;
2996 }
2997 
2998 static inline int hrtick_enabled(struct rq *rq)
2999 {
3000 	return 0;
3001 }
3002 
3003 #endif /* !CONFIG_SCHED_HRTICK */
3004 
3005 #ifndef arch_scale_freq_tick
3006 static __always_inline void arch_scale_freq_tick(void) { }
3007 #endif
3008 
3009 #ifndef arch_scale_freq_capacity
3010 /**
3011  * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
3012  * @cpu: the CPU in question.
3013  *
3014  * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
3015  *
3016  *     f_curr
3017  *     ------ * SCHED_CAPACITY_SCALE
3018  *     f_max
3019  */
3020 static __always_inline
3021 unsigned long arch_scale_freq_capacity(int cpu)
3022 {
3023 	return SCHED_CAPACITY_SCALE;
3024 }
3025 #endif
3026 
3027 /*
3028  * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to
3029  * acquire rq lock instead of rq_lock(). So at the end of these two functions
3030  * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of
3031  * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning.
3032  */
3033 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2)
3034 {
3035 	rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
3036 	rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
3037 }
3038 
3039 #define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...)				\
3040 __DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__)			\
3041 static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2)	\
3042 { class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t;			\
3043   _lock; return _t; }
3044 
3045 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2)
3046 {
3047 #ifdef CONFIG_SCHED_CORE
3048 	/*
3049 	 * In order to not have {0,2},{1,3} turn into into an AB-BA,
3050 	 * order by core-id first and cpu-id second.
3051 	 *
3052 	 * Notably:
3053 	 *
3054 	 *	double_rq_lock(0,3); will take core-0, core-1 lock
3055 	 *	double_rq_lock(1,2); will take core-1, core-0 lock
3056 	 *
3057 	 * when only cpu-id is considered.
3058 	 */
3059 	if (rq1->core->cpu < rq2->core->cpu)
3060 		return true;
3061 	if (rq1->core->cpu > rq2->core->cpu)
3062 		return false;
3063 
3064 	/*
3065 	 * __sched_core_flip() relies on SMT having cpu-id lock order.
3066 	 */
3067 #endif /* CONFIG_SCHED_CORE */
3068 	return rq1->cpu < rq2->cpu;
3069 }
3070 
3071 extern void double_rq_lock(struct rq *rq1, struct rq *rq2);
3072 
3073 #ifdef CONFIG_PREEMPTION
3074 
3075 /*
3076  * fair double_lock_balance: Safely acquires both rq->locks in a fair
3077  * way at the expense of forcing extra atomic operations in all
3078  * invocations.  This assures that the double_lock is acquired using the
3079  * same underlying policy as the spinlock_t on this architecture, which
3080  * reduces latency compared to the unfair variant below.  However, it
3081  * also adds more overhead and therefore may reduce throughput.
3082  */
3083 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
3084 	__releases(this_rq->lock)
3085 	__acquires(busiest->lock)
3086 	__acquires(this_rq->lock)
3087 {
3088 	raw_spin_rq_unlock(this_rq);
3089 	double_rq_lock(this_rq, busiest);
3090 
3091 	return 1;
3092 }
3093 
3094 #else /* !CONFIG_PREEMPTION: */
3095 /*
3096  * Unfair double_lock_balance: Optimizes throughput at the expense of
3097  * latency by eliminating extra atomic operations when the locks are
3098  * already in proper order on entry.  This favors lower CPU-ids and will
3099  * grant the double lock to lower CPUs over higher ids under contention,
3100  * regardless of entry order into the function.
3101  */
3102 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
3103 	__releases(this_rq->lock)
3104 	__acquires(busiest->lock)
3105 	__acquires(this_rq->lock)
3106 {
3107 	if (__rq_lockp(this_rq) == __rq_lockp(busiest) ||
3108 	    likely(raw_spin_rq_trylock(busiest))) {
3109 		double_rq_clock_clear_update(this_rq, busiest);
3110 		return 0;
3111 	}
3112 
3113 	if (rq_order_less(this_rq, busiest)) {
3114 		raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING);
3115 		double_rq_clock_clear_update(this_rq, busiest);
3116 		return 0;
3117 	}
3118 
3119 	raw_spin_rq_unlock(this_rq);
3120 	double_rq_lock(this_rq, busiest);
3121 
3122 	return 1;
3123 }
3124 
3125 #endif /* !CONFIG_PREEMPTION */
3126 
3127 /*
3128  * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
3129  */
3130 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
3131 {
3132 	lockdep_assert_irqs_disabled();
3133 
3134 	return _double_lock_balance(this_rq, busiest);
3135 }
3136 
3137 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
3138 	__releases(busiest->lock)
3139 {
3140 	if (__rq_lockp(this_rq) != __rq_lockp(busiest))
3141 		raw_spin_rq_unlock(busiest);
3142 	lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_);
3143 }
3144 
3145 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
3146 {
3147 	if (l1 > l2)
3148 		swap(l1, l2);
3149 
3150 	spin_lock(l1);
3151 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3152 }
3153 
3154 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
3155 {
3156 	if (l1 > l2)
3157 		swap(l1, l2);
3158 
3159 	spin_lock_irq(l1);
3160 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3161 }
3162 
3163 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
3164 {
3165 	if (l1 > l2)
3166 		swap(l1, l2);
3167 
3168 	raw_spin_lock(l1);
3169 	raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3170 }
3171 
3172 static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2)
3173 {
3174 	raw_spin_unlock(l1);
3175 	raw_spin_unlock(l2);
3176 }
3177 
3178 DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t,
3179 		    double_raw_lock(_T->lock, _T->lock2),
3180 		    double_raw_unlock(_T->lock, _T->lock2))
3181 
3182 /*
3183  * double_rq_unlock - safely unlock two runqueues
3184  *
3185  * Note this does not restore interrupts like task_rq_unlock,
3186  * you need to do so manually after calling.
3187  */
3188 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
3189 	__releases(rq1->lock)
3190 	__releases(rq2->lock)
3191 {
3192 	if (__rq_lockp(rq1) != __rq_lockp(rq2))
3193 		raw_spin_rq_unlock(rq2);
3194 	else
3195 		__release(rq2->lock);
3196 	raw_spin_rq_unlock(rq1);
3197 }
3198 
3199 extern void set_rq_online (struct rq *rq);
3200 extern void set_rq_offline(struct rq *rq);
3201 
3202 extern bool sched_smp_initialized;
3203 
3204 DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq,
3205 		    double_rq_lock(_T->lock, _T->lock2),
3206 		    double_rq_unlock(_T->lock, _T->lock2))
3207 
3208 extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq);
3209 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
3210 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
3211 
3212 extern bool sched_debug_verbose;
3213 
3214 extern void print_cfs_stats(struct seq_file *m, int cpu);
3215 extern void print_rt_stats(struct seq_file *m, int cpu);
3216 extern void print_dl_stats(struct seq_file *m, int cpu);
3217 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
3218 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
3219 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
3220 
3221 extern void resched_latency_warn(int cpu, u64 latency);
3222 
3223 #ifdef CONFIG_NUMA_BALANCING
3224 extern void show_numa_stats(struct task_struct *p, struct seq_file *m);
3225 extern void
3226 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
3227 		 unsigned long tpf, unsigned long gsf, unsigned long gpf);
3228 #endif /* CONFIG_NUMA_BALANCING */
3229 
3230 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
3231 extern void init_rt_rq(struct rt_rq *rt_rq);
3232 extern void init_dl_rq(struct dl_rq *dl_rq);
3233 
3234 extern void cfs_bandwidth_usage_inc(void);
3235 extern void cfs_bandwidth_usage_dec(void);
3236 
3237 #ifdef CONFIG_NO_HZ_COMMON
3238 
3239 #define NOHZ_BALANCE_KICK_BIT	0
3240 #define NOHZ_STATS_KICK_BIT	1
3241 #define NOHZ_NEWILB_KICK_BIT	2
3242 #define NOHZ_NEXT_KICK_BIT	3
3243 
3244 /* Run sched_balance_domains() */
3245 #define NOHZ_BALANCE_KICK	BIT(NOHZ_BALANCE_KICK_BIT)
3246 /* Update blocked load */
3247 #define NOHZ_STATS_KICK		BIT(NOHZ_STATS_KICK_BIT)
3248 /* Update blocked load when entering idle */
3249 #define NOHZ_NEWILB_KICK	BIT(NOHZ_NEWILB_KICK_BIT)
3250 /* Update nohz.next_balance */
3251 #define NOHZ_NEXT_KICK		BIT(NOHZ_NEXT_KICK_BIT)
3252 
3253 #define NOHZ_KICK_MASK		(NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK)
3254 
3255 #define nohz_flags(cpu)		(&cpu_rq(cpu)->nohz_flags)
3256 
3257 extern void nohz_balance_exit_idle(struct rq *rq);
3258 #else /* !CONFIG_NO_HZ_COMMON: */
3259 static inline void nohz_balance_exit_idle(struct rq *rq) { }
3260 #endif /* !CONFIG_NO_HZ_COMMON */
3261 
3262 #ifdef CONFIG_NO_HZ_COMMON
3263 extern void nohz_run_idle_balance(int cpu);
3264 #else
3265 static inline void nohz_run_idle_balance(int cpu) { }
3266 #endif
3267 
3268 #include "stats.h"
3269 
3270 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS)
3271 
3272 extern void __sched_core_account_forceidle(struct rq *rq);
3273 
3274 static inline void sched_core_account_forceidle(struct rq *rq)
3275 {
3276 	if (schedstat_enabled())
3277 		__sched_core_account_forceidle(rq);
3278 }
3279 
3280 extern void __sched_core_tick(struct rq *rq);
3281 
3282 static inline void sched_core_tick(struct rq *rq)
3283 {
3284 	if (sched_core_enabled(rq) && schedstat_enabled())
3285 		__sched_core_tick(rq);
3286 }
3287 
3288 #else /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS): */
3289 
3290 static inline void sched_core_account_forceidle(struct rq *rq) { }
3291 
3292 static inline void sched_core_tick(struct rq *rq) { }
3293 
3294 #endif /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS) */
3295 
3296 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
3297 
3298 struct irqtime {
3299 	u64			total;
3300 	u64			tick_delta;
3301 	u64			irq_start_time;
3302 	struct u64_stats_sync	sync;
3303 };
3304 
3305 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
3306 extern int sched_clock_irqtime;
3307 
3308 static inline int irqtime_enabled(void)
3309 {
3310 	return sched_clock_irqtime;
3311 }
3312 
3313 /*
3314  * Returns the irqtime minus the softirq time computed by ksoftirqd.
3315  * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime
3316  * and never move forward.
3317  */
3318 static inline u64 irq_time_read(int cpu)
3319 {
3320 	struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
3321 	unsigned int seq;
3322 	u64 total;
3323 
3324 	do {
3325 		seq = __u64_stats_fetch_begin(&irqtime->sync);
3326 		total = irqtime->total;
3327 	} while (__u64_stats_fetch_retry(&irqtime->sync, seq));
3328 
3329 	return total;
3330 }
3331 
3332 #else /* !CONFIG_IRQ_TIME_ACCOUNTING: */
3333 
3334 static inline int irqtime_enabled(void)
3335 {
3336 	return 0;
3337 }
3338 
3339 #endif /* !CONFIG_IRQ_TIME_ACCOUNTING */
3340 
3341 #ifdef CONFIG_CPU_FREQ
3342 
3343 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
3344 
3345 /**
3346  * cpufreq_update_util - Take a note about CPU utilization changes.
3347  * @rq: Runqueue to carry out the update for.
3348  * @flags: Update reason flags.
3349  *
3350  * This function is called by the scheduler on the CPU whose utilization is
3351  * being updated.
3352  *
3353  * It can only be called from RCU-sched read-side critical sections.
3354  *
3355  * The way cpufreq is currently arranged requires it to evaluate the CPU
3356  * performance state (frequency/voltage) on a regular basis to prevent it from
3357  * being stuck in a completely inadequate performance level for too long.
3358  * That is not guaranteed to happen if the updates are only triggered from CFS
3359  * and DL, though, because they may not be coming in if only RT tasks are
3360  * active all the time (or there are RT tasks only).
3361  *
3362  * As a workaround for that issue, this function is called periodically by the
3363  * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
3364  * but that really is a band-aid.  Going forward it should be replaced with
3365  * solutions targeted more specifically at RT tasks.
3366  */
3367 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
3368 {
3369 	struct update_util_data *data;
3370 
3371 	data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
3372 						  cpu_of(rq)));
3373 	if (data)
3374 		data->func(data, rq_clock(rq), flags);
3375 }
3376 #else /* !CONFIG_CPU_FREQ: */
3377 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) { }
3378 #endif /* !CONFIG_CPU_FREQ */
3379 
3380 #ifdef arch_scale_freq_capacity
3381 # ifndef arch_scale_freq_invariant
3382 #  define arch_scale_freq_invariant()	true
3383 # endif
3384 #else
3385 # define arch_scale_freq_invariant()	false
3386 #endif
3387 
3388 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
3389 				 unsigned long *min,
3390 				 unsigned long *max);
3391 
3392 unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual,
3393 				 unsigned long min,
3394 				 unsigned long max);
3395 
3396 
3397 /*
3398  * Verify the fitness of task @p to run on @cpu taking into account the
3399  * CPU original capacity and the runtime/deadline ratio of the task.
3400  *
3401  * The function will return true if the original capacity of @cpu is
3402  * greater than or equal to task's deadline density right shifted by
3403  * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise.
3404  */
3405 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
3406 {
3407 	unsigned long cap = arch_scale_cpu_capacity(cpu);
3408 
3409 	return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT);
3410 }
3411 
3412 static inline unsigned long cpu_bw_dl(struct rq *rq)
3413 {
3414 	return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
3415 }
3416 
3417 static inline unsigned long cpu_util_dl(struct rq *rq)
3418 {
3419 	return READ_ONCE(rq->avg_dl.util_avg);
3420 }
3421 
3422 
3423 extern unsigned long cpu_util_cfs(int cpu);
3424 extern unsigned long cpu_util_cfs_boost(int cpu);
3425 
3426 static inline unsigned long cpu_util_rt(struct rq *rq)
3427 {
3428 	return READ_ONCE(rq->avg_rt.util_avg);
3429 }
3430 
3431 #ifdef CONFIG_UCLAMP_TASK
3432 
3433 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
3434 
3435 /*
3436  * When uclamp is compiled in, the aggregation at rq level is 'turned off'
3437  * by default in the fast path and only gets turned on once userspace performs
3438  * an operation that requires it.
3439  *
3440  * Returns true if userspace opted-in to use uclamp and aggregation at rq level
3441  * hence is active.
3442  */
3443 static inline bool uclamp_is_used(void)
3444 {
3445 	return static_branch_likely(&sched_uclamp_used);
3446 }
3447 
3448 /*
3449  * Enabling static branches would get the cpus_read_lock(),
3450  * check whether uclamp_is_used before enable it to avoid always
3451  * calling cpus_read_lock(). Because we never disable this
3452  * static key once enable it.
3453  */
3454 static inline void sched_uclamp_enable(void)
3455 {
3456 	if (!uclamp_is_used())
3457 		static_branch_enable(&sched_uclamp_used);
3458 }
3459 
3460 static inline unsigned long uclamp_rq_get(struct rq *rq,
3461 					  enum uclamp_id clamp_id)
3462 {
3463 	return READ_ONCE(rq->uclamp[clamp_id].value);
3464 }
3465 
3466 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id,
3467 				 unsigned int value)
3468 {
3469 	WRITE_ONCE(rq->uclamp[clamp_id].value, value);
3470 }
3471 
3472 static inline bool uclamp_rq_is_idle(struct rq *rq)
3473 {
3474 	return rq->uclamp_flags & UCLAMP_FLAG_IDLE;
3475 }
3476 
3477 /* Is the rq being capped/throttled by uclamp_max? */
3478 static inline bool uclamp_rq_is_capped(struct rq *rq)
3479 {
3480 	unsigned long rq_util;
3481 	unsigned long max_util;
3482 
3483 	if (!uclamp_is_used())
3484 		return false;
3485 
3486 	rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq);
3487 	max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
3488 
3489 	return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util;
3490 }
3491 
3492 #define for_each_clamp_id(clamp_id) \
3493 	for ((clamp_id) = 0; (clamp_id) < UCLAMP_CNT; (clamp_id)++)
3494 
3495 extern unsigned int sysctl_sched_uclamp_util_min_rt_default;
3496 
3497 
3498 static inline unsigned int uclamp_none(enum uclamp_id clamp_id)
3499 {
3500 	if (clamp_id == UCLAMP_MIN)
3501 		return 0;
3502 	return SCHED_CAPACITY_SCALE;
3503 }
3504 
3505 /* Integer rounded range for each bucket */
3506 #define UCLAMP_BUCKET_DELTA DIV_ROUND_CLOSEST(SCHED_CAPACITY_SCALE, UCLAMP_BUCKETS)
3507 
3508 static inline unsigned int uclamp_bucket_id(unsigned int clamp_value)
3509 {
3510 	return min_t(unsigned int, clamp_value / UCLAMP_BUCKET_DELTA, UCLAMP_BUCKETS - 1);
3511 }
3512 
3513 static inline void
3514 uclamp_se_set(struct uclamp_se *uc_se, unsigned int value, bool user_defined)
3515 {
3516 	uc_se->value = value;
3517 	uc_se->bucket_id = uclamp_bucket_id(value);
3518 	uc_se->user_defined = user_defined;
3519 }
3520 
3521 #else /* !CONFIG_UCLAMP_TASK: */
3522 
3523 static inline unsigned long
3524 uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id)
3525 {
3526 	if (clamp_id == UCLAMP_MIN)
3527 		return 0;
3528 
3529 	return SCHED_CAPACITY_SCALE;
3530 }
3531 
3532 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; }
3533 
3534 static inline bool uclamp_is_used(void)
3535 {
3536 	return false;
3537 }
3538 
3539 static inline void sched_uclamp_enable(void) {}
3540 
3541 static inline unsigned long
3542 uclamp_rq_get(struct rq *rq, enum uclamp_id clamp_id)
3543 {
3544 	if (clamp_id == UCLAMP_MIN)
3545 		return 0;
3546 
3547 	return SCHED_CAPACITY_SCALE;
3548 }
3549 
3550 static inline void
3551 uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, unsigned int value)
3552 {
3553 }
3554 
3555 static inline bool uclamp_rq_is_idle(struct rq *rq)
3556 {
3557 	return false;
3558 }
3559 
3560 #endif /* !CONFIG_UCLAMP_TASK */
3561 
3562 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
3563 
3564 static inline unsigned long cpu_util_irq(struct rq *rq)
3565 {
3566 	return READ_ONCE(rq->avg_irq.util_avg);
3567 }
3568 
3569 static inline
3570 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3571 {
3572 	util *= (max - irq);
3573 	util /= max;
3574 
3575 	return util;
3576 
3577 }
3578 
3579 #else /* !CONFIG_HAVE_SCHED_AVG_IRQ: */
3580 
3581 static inline unsigned long cpu_util_irq(struct rq *rq)
3582 {
3583 	return 0;
3584 }
3585 
3586 static inline
3587 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3588 {
3589 	return util;
3590 }
3591 
3592 #endif /* !CONFIG_HAVE_SCHED_AVG_IRQ */
3593 
3594 extern void __setparam_fair(struct task_struct *p, const struct sched_attr *attr);
3595 
3596 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
3597 
3598 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
3599 
3600 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
3601 
3602 static inline bool sched_energy_enabled(void)
3603 {
3604 	return static_branch_unlikely(&sched_energy_present);
3605 }
3606 
3607 #else /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL): */
3608 
3609 #define perf_domain_span(pd) NULL
3610 
3611 static inline bool sched_energy_enabled(void) { return false; }
3612 
3613 #endif /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
3614 
3615 #ifdef CONFIG_MEMBARRIER
3616 
3617 /*
3618  * The scheduler provides memory barriers required by membarrier between:
3619  * - prior user-space memory accesses and store to rq->membarrier_state,
3620  * - store to rq->membarrier_state and following user-space memory accesses.
3621  * In the same way it provides those guarantees around store to rq->curr.
3622  */
3623 static inline void membarrier_switch_mm(struct rq *rq,
3624 					struct mm_struct *prev_mm,
3625 					struct mm_struct *next_mm)
3626 {
3627 	int membarrier_state;
3628 
3629 	if (prev_mm == next_mm)
3630 		return;
3631 
3632 	membarrier_state = atomic_read(&next_mm->membarrier_state);
3633 	if (READ_ONCE(rq->membarrier_state) == membarrier_state)
3634 		return;
3635 
3636 	WRITE_ONCE(rq->membarrier_state, membarrier_state);
3637 }
3638 
3639 #else /* !CONFIG_MEMBARRIER: */
3640 
3641 static inline void membarrier_switch_mm(struct rq *rq,
3642 					struct mm_struct *prev_mm,
3643 					struct mm_struct *next_mm)
3644 {
3645 }
3646 
3647 #endif /* !CONFIG_MEMBARRIER */
3648 
3649 static inline bool is_per_cpu_kthread(struct task_struct *p)
3650 {
3651 	if (!(p->flags & PF_KTHREAD))
3652 		return false;
3653 
3654 	if (p->nr_cpus_allowed != 1)
3655 		return false;
3656 
3657 	return true;
3658 }
3659 
3660 extern void swake_up_all_locked(struct swait_queue_head *q);
3661 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
3662 
3663 extern int try_to_wake_up(struct task_struct *tsk, unsigned int state, int wake_flags);
3664 
3665 #ifdef CONFIG_PREEMPT_DYNAMIC
3666 extern int preempt_dynamic_mode;
3667 extern int sched_dynamic_mode(const char *str);
3668 extern void sched_dynamic_update(int mode);
3669 #endif
3670 extern const char *preempt_modes[];
3671 
3672 #ifdef CONFIG_SCHED_MM_CID
3673 
3674 #define SCHED_MM_CID_PERIOD_NS	(100ULL * 1000000)	/* 100ms */
3675 #define MM_CID_SCAN_DELAY	100			/* 100ms */
3676 
3677 extern raw_spinlock_t cid_lock;
3678 extern int use_cid_lock;
3679 
3680 extern void sched_mm_cid_migrate_from(struct task_struct *t);
3681 extern void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t);
3682 extern void task_tick_mm_cid(struct rq *rq, struct task_struct *curr);
3683 extern void init_sched_mm_cid(struct task_struct *t);
3684 
3685 static inline void __mm_cid_put(struct mm_struct *mm, int cid)
3686 {
3687 	if (cid < 0)
3688 		return;
3689 	cpumask_clear_cpu(cid, mm_cidmask(mm));
3690 }
3691 
3692 /*
3693  * The per-mm/cpu cid can have the MM_CID_LAZY_PUT flag set or transition to
3694  * the MM_CID_UNSET state without holding the rq lock, but the rq lock needs to
3695  * be held to transition to other states.
3696  *
3697  * State transitions synchronized with cmpxchg or try_cmpxchg need to be
3698  * consistent across CPUs, which prevents use of this_cpu_cmpxchg.
3699  */
3700 static inline void mm_cid_put_lazy(struct task_struct *t)
3701 {
3702 	struct mm_struct *mm = t->mm;
3703 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3704 	int cid;
3705 
3706 	lockdep_assert_irqs_disabled();
3707 	cid = __this_cpu_read(pcpu_cid->cid);
3708 	if (!mm_cid_is_lazy_put(cid) ||
3709 	    !try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET))
3710 		return;
3711 	__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3712 }
3713 
3714 static inline int mm_cid_pcpu_unset(struct mm_struct *mm)
3715 {
3716 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3717 	int cid, res;
3718 
3719 	lockdep_assert_irqs_disabled();
3720 	cid = __this_cpu_read(pcpu_cid->cid);
3721 	for (;;) {
3722 		if (mm_cid_is_unset(cid))
3723 			return MM_CID_UNSET;
3724 		/*
3725 		 * Attempt transition from valid or lazy-put to unset.
3726 		 */
3727 		res = cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, cid, MM_CID_UNSET);
3728 		if (res == cid)
3729 			break;
3730 		cid = res;
3731 	}
3732 	return cid;
3733 }
3734 
3735 static inline void mm_cid_put(struct mm_struct *mm)
3736 {
3737 	int cid;
3738 
3739 	lockdep_assert_irqs_disabled();
3740 	cid = mm_cid_pcpu_unset(mm);
3741 	if (cid == MM_CID_UNSET)
3742 		return;
3743 	__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3744 }
3745 
3746 static inline int __mm_cid_try_get(struct task_struct *t, struct mm_struct *mm)
3747 {
3748 	struct cpumask *cidmask = mm_cidmask(mm);
3749 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3750 	int cid, max_nr_cid, allowed_max_nr_cid;
3751 
3752 	/*
3753 	 * After shrinking the number of threads or reducing the number
3754 	 * of allowed cpus, reduce the value of max_nr_cid so expansion
3755 	 * of cid allocation will preserve cache locality if the number
3756 	 * of threads or allowed cpus increase again.
3757 	 */
3758 	max_nr_cid = atomic_read(&mm->max_nr_cid);
3759 	while ((allowed_max_nr_cid = min_t(int, READ_ONCE(mm->nr_cpus_allowed),
3760 					   atomic_read(&mm->mm_users))),
3761 	       max_nr_cid > allowed_max_nr_cid) {
3762 		/* atomic_try_cmpxchg loads previous mm->max_nr_cid into max_nr_cid. */
3763 		if (atomic_try_cmpxchg(&mm->max_nr_cid, &max_nr_cid, allowed_max_nr_cid)) {
3764 			max_nr_cid = allowed_max_nr_cid;
3765 			break;
3766 		}
3767 	}
3768 	/* Try to re-use recent cid. This improves cache locality. */
3769 	cid = __this_cpu_read(pcpu_cid->recent_cid);
3770 	if (!mm_cid_is_unset(cid) && cid < max_nr_cid &&
3771 	    !cpumask_test_and_set_cpu(cid, cidmask))
3772 		return cid;
3773 	/*
3774 	 * Expand cid allocation if the maximum number of concurrency
3775 	 * IDs allocated (max_nr_cid) is below the number cpus allowed
3776 	 * and number of threads. Expanding cid allocation as much as
3777 	 * possible improves cache locality.
3778 	 */
3779 	cid = max_nr_cid;
3780 	while (cid < READ_ONCE(mm->nr_cpus_allowed) && cid < atomic_read(&mm->mm_users)) {
3781 		/* atomic_try_cmpxchg loads previous mm->max_nr_cid into cid. */
3782 		if (!atomic_try_cmpxchg(&mm->max_nr_cid, &cid, cid + 1))
3783 			continue;
3784 		if (!cpumask_test_and_set_cpu(cid, cidmask))
3785 			return cid;
3786 	}
3787 	/*
3788 	 * Find the first available concurrency id.
3789 	 * Retry finding first zero bit if the mask is temporarily
3790 	 * filled. This only happens during concurrent remote-clear
3791 	 * which owns a cid without holding a rq lock.
3792 	 */
3793 	for (;;) {
3794 		cid = cpumask_first_zero(cidmask);
3795 		if (cid < READ_ONCE(mm->nr_cpus_allowed))
3796 			break;
3797 		cpu_relax();
3798 	}
3799 	if (cpumask_test_and_set_cpu(cid, cidmask))
3800 		return -1;
3801 
3802 	return cid;
3803 }
3804 
3805 /*
3806  * Save a snapshot of the current runqueue time of this cpu
3807  * with the per-cpu cid value, allowing to estimate how recently it was used.
3808  */
3809 static inline void mm_cid_snapshot_time(struct rq *rq, struct mm_struct *mm)
3810 {
3811 	struct mm_cid *pcpu_cid = per_cpu_ptr(mm->pcpu_cid, cpu_of(rq));
3812 
3813 	lockdep_assert_rq_held(rq);
3814 	WRITE_ONCE(pcpu_cid->time, rq->clock);
3815 }
3816 
3817 static inline int __mm_cid_get(struct rq *rq, struct task_struct *t,
3818 			       struct mm_struct *mm)
3819 {
3820 	int cid;
3821 
3822 	/*
3823 	 * All allocations (even those using the cid_lock) are lock-free. If
3824 	 * use_cid_lock is set, hold the cid_lock to perform cid allocation to
3825 	 * guarantee forward progress.
3826 	 */
3827 	if (!READ_ONCE(use_cid_lock)) {
3828 		cid = __mm_cid_try_get(t, mm);
3829 		if (cid >= 0)
3830 			goto end;
3831 		raw_spin_lock(&cid_lock);
3832 	} else {
3833 		raw_spin_lock(&cid_lock);
3834 		cid = __mm_cid_try_get(t, mm);
3835 		if (cid >= 0)
3836 			goto unlock;
3837 	}
3838 
3839 	/*
3840 	 * cid concurrently allocated. Retry while forcing following
3841 	 * allocations to use the cid_lock to ensure forward progress.
3842 	 */
3843 	WRITE_ONCE(use_cid_lock, 1);
3844 	/*
3845 	 * Set use_cid_lock before allocation. Only care about program order
3846 	 * because this is only required for forward progress.
3847 	 */
3848 	barrier();
3849 	/*
3850 	 * Retry until it succeeds. It is guaranteed to eventually succeed once
3851 	 * all newcoming allocations observe the use_cid_lock flag set.
3852 	 */
3853 	do {
3854 		cid = __mm_cid_try_get(t, mm);
3855 		cpu_relax();
3856 	} while (cid < 0);
3857 	/*
3858 	 * Allocate before clearing use_cid_lock. Only care about
3859 	 * program order because this is for forward progress.
3860 	 */
3861 	barrier();
3862 	WRITE_ONCE(use_cid_lock, 0);
3863 unlock:
3864 	raw_spin_unlock(&cid_lock);
3865 end:
3866 	mm_cid_snapshot_time(rq, mm);
3867 
3868 	return cid;
3869 }
3870 
3871 static inline int mm_cid_get(struct rq *rq, struct task_struct *t,
3872 			     struct mm_struct *mm)
3873 {
3874 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3875 	struct cpumask *cpumask;
3876 	int cid;
3877 
3878 	lockdep_assert_rq_held(rq);
3879 	cpumask = mm_cidmask(mm);
3880 	cid = __this_cpu_read(pcpu_cid->cid);
3881 	if (mm_cid_is_valid(cid)) {
3882 		mm_cid_snapshot_time(rq, mm);
3883 		return cid;
3884 	}
3885 	if (mm_cid_is_lazy_put(cid)) {
3886 		if (try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET))
3887 			__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3888 	}
3889 	cid = __mm_cid_get(rq, t, mm);
3890 	__this_cpu_write(pcpu_cid->cid, cid);
3891 	__this_cpu_write(pcpu_cid->recent_cid, cid);
3892 
3893 	return cid;
3894 }
3895 
3896 static inline void switch_mm_cid(struct rq *rq,
3897 				 struct task_struct *prev,
3898 				 struct task_struct *next)
3899 {
3900 	/*
3901 	 * Provide a memory barrier between rq->curr store and load of
3902 	 * {prev,next}->mm->pcpu_cid[cpu] on rq->curr->mm transition.
3903 	 *
3904 	 * Should be adapted if context_switch() is modified.
3905 	 */
3906 	if (!next->mm) {                                // to kernel
3907 		/*
3908 		 * user -> kernel transition does not guarantee a barrier, but
3909 		 * we can use the fact that it performs an atomic operation in
3910 		 * mmgrab().
3911 		 */
3912 		if (prev->mm)                           // from user
3913 			smp_mb__after_mmgrab();
3914 		/*
3915 		 * kernel -> kernel transition does not change rq->curr->mm
3916 		 * state. It stays NULL.
3917 		 */
3918 	} else {                                        // to user
3919 		/*
3920 		 * kernel -> user transition does not provide a barrier
3921 		 * between rq->curr store and load of {prev,next}->mm->pcpu_cid[cpu].
3922 		 * Provide it here.
3923 		 */
3924 		if (!prev->mm) {                        // from kernel
3925 			smp_mb();
3926 		} else {				// from user
3927 			/*
3928 			 * user->user transition relies on an implicit
3929 			 * memory barrier in switch_mm() when
3930 			 * current->mm changes. If the architecture
3931 			 * switch_mm() does not have an implicit memory
3932 			 * barrier, it is emitted here.  If current->mm
3933 			 * is unchanged, no barrier is needed.
3934 			 */
3935 			smp_mb__after_switch_mm();
3936 		}
3937 	}
3938 	if (prev->mm_cid_active) {
3939 		mm_cid_snapshot_time(rq, prev->mm);
3940 		mm_cid_put_lazy(prev);
3941 		prev->mm_cid = -1;
3942 	}
3943 	if (next->mm_cid_active)
3944 		next->last_mm_cid = next->mm_cid = mm_cid_get(rq, next, next->mm);
3945 }
3946 
3947 #else /* !CONFIG_SCHED_MM_CID: */
3948 static inline void switch_mm_cid(struct rq *rq, struct task_struct *prev, struct task_struct *next) { }
3949 static inline void sched_mm_cid_migrate_from(struct task_struct *t) { }
3950 static inline void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t) { }
3951 static inline void task_tick_mm_cid(struct rq *rq, struct task_struct *curr) { }
3952 static inline void init_sched_mm_cid(struct task_struct *t) { }
3953 #endif /* !CONFIG_SCHED_MM_CID */
3954 
3955 extern u64 avg_vruntime(struct cfs_rq *cfs_rq);
3956 extern int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se);
3957 static inline
3958 void move_queued_task_locked(struct rq *src_rq, struct rq *dst_rq, struct task_struct *task)
3959 {
3960 	lockdep_assert_rq_held(src_rq);
3961 	lockdep_assert_rq_held(dst_rq);
3962 
3963 	deactivate_task(src_rq, task, 0);
3964 	set_task_cpu(task, dst_rq->cpu);
3965 	activate_task(dst_rq, task, 0);
3966 }
3967 
3968 static inline
3969 bool task_is_pushable(struct rq *rq, struct task_struct *p, int cpu)
3970 {
3971 	if (!task_on_cpu(rq, p) &&
3972 	    cpumask_test_cpu(cpu, &p->cpus_mask))
3973 		return true;
3974 
3975 	return false;
3976 }
3977 
3978 #ifdef CONFIG_RT_MUTEXES
3979 
3980 static inline int __rt_effective_prio(struct task_struct *pi_task, int prio)
3981 {
3982 	if (pi_task)
3983 		prio = min(prio, pi_task->prio);
3984 
3985 	return prio;
3986 }
3987 
3988 static inline int rt_effective_prio(struct task_struct *p, int prio)
3989 {
3990 	struct task_struct *pi_task = rt_mutex_get_top_task(p);
3991 
3992 	return __rt_effective_prio(pi_task, prio);
3993 }
3994 
3995 #else /* !CONFIG_RT_MUTEXES: */
3996 
3997 static inline int rt_effective_prio(struct task_struct *p, int prio)
3998 {
3999 	return prio;
4000 }
4001 
4002 #endif /* !CONFIG_RT_MUTEXES */
4003 
4004 extern int __sched_setscheduler(struct task_struct *p, const struct sched_attr *attr, bool user, bool pi);
4005 extern int __sched_setaffinity(struct task_struct *p, struct affinity_context *ctx);
4006 extern const struct sched_class *__setscheduler_class(int policy, int prio);
4007 extern void set_load_weight(struct task_struct *p, bool update_load);
4008 extern void enqueue_task(struct rq *rq, struct task_struct *p, int flags);
4009 extern bool dequeue_task(struct rq *rq, struct task_struct *p, int flags);
4010 
4011 extern struct balance_callback *splice_balance_callbacks(struct rq *rq);
4012 extern void balance_callbacks(struct rq *rq, struct balance_callback *head);
4013 
4014 /*
4015  * The 'sched_change' pattern is the safe, easy and slow way of changing a
4016  * task's scheduling properties. It dequeues a task, such that the scheduler
4017  * is fully unaware of it; at which point its properties can be modified;
4018  * after which it is enqueued again.
4019  *
4020  * Typically this must be called while holding task_rq_lock, since most/all
4021  * properties are serialized under those locks. There is currently one
4022  * exception to this rule in sched/ext which only holds rq->lock.
4023  */
4024 
4025 /*
4026  * This structure is a temporary, used to preserve/convey the queueing state
4027  * of the task between sched_change_begin() and sched_change_end(). Ensuring
4028  * the task's queueing state is idempotent across the operation.
4029  */
4030 struct sched_change_ctx {
4031 	u64			prio;
4032 	struct task_struct	*p;
4033 	int			flags;
4034 	bool			queued;
4035 	bool			running;
4036 };
4037 
4038 struct sched_change_ctx *sched_change_begin(struct task_struct *p, unsigned int flags);
4039 void sched_change_end(struct sched_change_ctx *ctx);
4040 
4041 DEFINE_CLASS(sched_change, struct sched_change_ctx *,
4042 	     sched_change_end(_T),
4043 	     sched_change_begin(p, flags),
4044 	     struct task_struct *p, unsigned int flags)
4045 
4046 DEFINE_CLASS_IS_UNCONDITIONAL(sched_change)
4047 
4048 #include "ext.h"
4049 
4050 #endif /* _KERNEL_SCHED_SCHED_H */
4051