xref: /linux/kernel/sched/sched.h (revision 2dbbdeda77a61b39dc4a34dfce873907cfea2c4b)
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		pnt_seq;
807 	struct balance_callback	deferred_bal_cb;
808 	struct irq_work		deferred_irq_work;
809 	struct irq_work		kick_cpus_irq_work;
810 };
811 #endif /* CONFIG_SCHED_CLASS_EXT */
812 
813 static inline int rt_bandwidth_enabled(void)
814 {
815 	return sysctl_sched_rt_runtime >= 0;
816 }
817 
818 /* RT IPI pull logic requires IRQ_WORK */
819 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
820 # define HAVE_RT_PUSH_IPI
821 #endif
822 
823 /* Real-Time classes' related field in a runqueue: */
824 struct rt_rq {
825 	struct rt_prio_array	active;
826 	unsigned int		rt_nr_running;
827 	unsigned int		rr_nr_running;
828 	struct {
829 		int		curr; /* highest queued rt task prio */
830 		int		next; /* next highest */
831 	} highest_prio;
832 	bool			overloaded;
833 	struct plist_head	pushable_tasks;
834 
835 	int			rt_queued;
836 
837 #ifdef CONFIG_RT_GROUP_SCHED
838 	int			rt_throttled;
839 	u64			rt_time; /* consumed RT time, goes up in update_curr_rt */
840 	u64			rt_runtime; /* allotted RT time, "slice" from rt_bandwidth, RT sharing/balancing */
841 	/* Nests inside the rq lock: */
842 	raw_spinlock_t		rt_runtime_lock;
843 
844 	unsigned int		rt_nr_boosted;
845 
846 	struct rq		*rq; /* this is always top-level rq, cache? */
847 #endif
848 #ifdef CONFIG_CGROUP_SCHED
849 	struct task_group	*tg; /* this tg has "this" rt_rq on given CPU for runnable entities */
850 #endif
851 };
852 
853 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
854 {
855 	return rt_rq->rt_queued && rt_rq->rt_nr_running;
856 }
857 
858 /* Deadline class' related fields in a runqueue */
859 struct dl_rq {
860 	/* runqueue is an rbtree, ordered by deadline */
861 	struct rb_root_cached	root;
862 
863 	unsigned int		dl_nr_running;
864 
865 	/*
866 	 * Deadline values of the currently executing and the
867 	 * earliest ready task on this rq. Caching these facilitates
868 	 * the decision whether or not a ready but not running task
869 	 * should migrate somewhere else.
870 	 */
871 	struct {
872 		u64		curr;
873 		u64		next;
874 	} earliest_dl;
875 
876 	bool			overloaded;
877 
878 	/*
879 	 * Tasks on this rq that can be pushed away. They are kept in
880 	 * an rb-tree, ordered by tasks' deadlines, with caching
881 	 * of the leftmost (earliest deadline) element.
882 	 */
883 	struct rb_root_cached	pushable_dl_tasks_root;
884 
885 	/*
886 	 * "Active utilization" for this runqueue: increased when a
887 	 * task wakes up (becomes TASK_RUNNING) and decreased when a
888 	 * task blocks
889 	 */
890 	u64			running_bw;
891 
892 	/*
893 	 * Utilization of the tasks "assigned" to this runqueue (including
894 	 * the tasks that are in runqueue and the tasks that executed on this
895 	 * CPU and blocked). Increased when a task moves to this runqueue, and
896 	 * decreased when the task moves away (migrates, changes scheduling
897 	 * policy, or terminates).
898 	 * This is needed to compute the "inactive utilization" for the
899 	 * runqueue (inactive utilization = this_bw - running_bw).
900 	 */
901 	u64			this_bw;
902 	u64			extra_bw;
903 
904 	/*
905 	 * Maximum available bandwidth for reclaiming by SCHED_FLAG_RECLAIM
906 	 * tasks of this rq. Used in calculation of reclaimable bandwidth(GRUB).
907 	 */
908 	u64			max_bw;
909 
910 	/*
911 	 * Inverse of the fraction of CPU utilization that can be reclaimed
912 	 * by the GRUB algorithm.
913 	 */
914 	u64			bw_ratio;
915 };
916 
917 #ifdef CONFIG_FAIR_GROUP_SCHED
918 
919 /* An entity is a task if it doesn't "own" a runqueue */
920 #define entity_is_task(se)	(!se->my_q)
921 
922 static inline void se_update_runnable(struct sched_entity *se)
923 {
924 	if (!entity_is_task(se))
925 		se->runnable_weight = se->my_q->h_nr_runnable;
926 }
927 
928 static inline long se_runnable(struct sched_entity *se)
929 {
930 	if (se->sched_delayed)
931 		return false;
932 
933 	if (entity_is_task(se))
934 		return !!se->on_rq;
935 	else
936 		return se->runnable_weight;
937 }
938 
939 #else /* !CONFIG_FAIR_GROUP_SCHED: */
940 
941 #define entity_is_task(se)	1
942 
943 static inline void se_update_runnable(struct sched_entity *se) { }
944 
945 static inline long se_runnable(struct sched_entity *se)
946 {
947 	if (se->sched_delayed)
948 		return false;
949 
950 	return !!se->on_rq;
951 }
952 
953 #endif /* !CONFIG_FAIR_GROUP_SCHED */
954 
955 /*
956  * XXX we want to get rid of these helpers and use the full load resolution.
957  */
958 static inline long se_weight(struct sched_entity *se)
959 {
960 	return scale_load_down(se->load.weight);
961 }
962 
963 
964 static inline bool sched_asym_prefer(int a, int b)
965 {
966 	return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
967 }
968 
969 struct perf_domain {
970 	struct em_perf_domain *em_pd;
971 	struct perf_domain *next;
972 	struct rcu_head rcu;
973 };
974 
975 /*
976  * We add the notion of a root-domain which will be used to define per-domain
977  * variables. Each exclusive cpuset essentially defines an island domain by
978  * fully partitioning the member CPUs from any other cpuset. Whenever a new
979  * exclusive cpuset is created, we also create and attach a new root-domain
980  * object.
981  *
982  */
983 struct root_domain {
984 	atomic_t		refcount;
985 	atomic_t		rto_count;
986 	struct rcu_head		rcu;
987 	cpumask_var_t		span;
988 	cpumask_var_t		online;
989 
990 	/*
991 	 * Indicate pullable load on at least one CPU, e.g:
992 	 * - More than one runnable task
993 	 * - Running task is misfit
994 	 */
995 	bool			overloaded;
996 
997 	/* Indicate one or more CPUs over-utilized (tipping point) */
998 	bool			overutilized;
999 
1000 	/*
1001 	 * The bit corresponding to a CPU gets set here if such CPU has more
1002 	 * than one runnable -deadline task (as it is below for RT tasks).
1003 	 */
1004 	cpumask_var_t		dlo_mask;
1005 	atomic_t		dlo_count;
1006 	struct dl_bw		dl_bw;
1007 	struct cpudl		cpudl;
1008 
1009 	/*
1010 	 * Indicate whether a root_domain's dl_bw has been checked or
1011 	 * updated. It's monotonously increasing value.
1012 	 *
1013 	 * Also, some corner cases, like 'wrap around' is dangerous, but given
1014 	 * that u64 is 'big enough'. So that shouldn't be a concern.
1015 	 */
1016 	u64 visit_cookie;
1017 
1018 #ifdef HAVE_RT_PUSH_IPI
1019 	/*
1020 	 * For IPI pull requests, loop across the rto_mask.
1021 	 */
1022 	struct irq_work		rto_push_work;
1023 	raw_spinlock_t		rto_lock;
1024 	/* These are only updated and read within rto_lock */
1025 	int			rto_loop;
1026 	int			rto_cpu;
1027 	/* These atomics are updated outside of a lock */
1028 	atomic_t		rto_loop_next;
1029 	atomic_t		rto_loop_start;
1030 #endif /* HAVE_RT_PUSH_IPI */
1031 	/*
1032 	 * The "RT overload" flag: it gets set if a CPU has more than
1033 	 * one runnable RT task.
1034 	 */
1035 	cpumask_var_t		rto_mask;
1036 	struct cpupri		cpupri;
1037 
1038 	/*
1039 	 * NULL-terminated list of performance domains intersecting with the
1040 	 * CPUs of the rd. Protected by RCU.
1041 	 */
1042 	struct perf_domain __rcu *pd;
1043 };
1044 
1045 extern void init_defrootdomain(void);
1046 extern int sched_init_domains(const struct cpumask *cpu_map);
1047 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
1048 extern void sched_get_rd(struct root_domain *rd);
1049 extern void sched_put_rd(struct root_domain *rd);
1050 
1051 static inline int get_rd_overloaded(struct root_domain *rd)
1052 {
1053 	return READ_ONCE(rd->overloaded);
1054 }
1055 
1056 static inline void set_rd_overloaded(struct root_domain *rd, int status)
1057 {
1058 	if (get_rd_overloaded(rd) != status)
1059 		WRITE_ONCE(rd->overloaded, status);
1060 }
1061 
1062 #ifdef HAVE_RT_PUSH_IPI
1063 extern void rto_push_irq_work_func(struct irq_work *work);
1064 #endif
1065 
1066 #ifdef CONFIG_UCLAMP_TASK
1067 /*
1068  * struct uclamp_bucket - Utilization clamp bucket
1069  * @value: utilization clamp value for tasks on this clamp bucket
1070  * @tasks: number of RUNNABLE tasks on this clamp bucket
1071  *
1072  * Keep track of how many tasks are RUNNABLE for a given utilization
1073  * clamp value.
1074  */
1075 struct uclamp_bucket {
1076 	unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
1077 	unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
1078 };
1079 
1080 /*
1081  * struct uclamp_rq - rq's utilization clamp
1082  * @value: currently active clamp values for a rq
1083  * @bucket: utilization clamp buckets affecting a rq
1084  *
1085  * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
1086  * A clamp value is affecting a rq when there is at least one task RUNNABLE
1087  * (or actually running) with that value.
1088  *
1089  * There are up to UCLAMP_CNT possible different clamp values, currently there
1090  * are only two: minimum utilization and maximum utilization.
1091  *
1092  * All utilization clamping values are MAX aggregated, since:
1093  * - for util_min: we want to run the CPU at least at the max of the minimum
1094  *   utilization required by its currently RUNNABLE tasks.
1095  * - for util_max: we want to allow the CPU to run up to the max of the
1096  *   maximum utilization allowed by its currently RUNNABLE tasks.
1097  *
1098  * Since on each system we expect only a limited number of different
1099  * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
1100  * the metrics required to compute all the per-rq utilization clamp values.
1101  */
1102 struct uclamp_rq {
1103 	unsigned int value;
1104 	struct uclamp_bucket bucket[UCLAMP_BUCKETS];
1105 };
1106 
1107 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
1108 #endif /* CONFIG_UCLAMP_TASK */
1109 
1110 /*
1111  * This is the main, per-CPU runqueue data structure.
1112  *
1113  * Locking rule: those places that want to lock multiple runqueues
1114  * (such as the load balancing or the thread migration code), lock
1115  * acquire operations must be ordered by ascending &runqueue.
1116  */
1117 struct rq {
1118 	/* runqueue lock: */
1119 	raw_spinlock_t		__lock;
1120 
1121 	/* Per class runqueue modification mask; bits in class order. */
1122 	unsigned int		queue_mask;
1123 	unsigned int		nr_running;
1124 #ifdef CONFIG_NUMA_BALANCING
1125 	unsigned int		nr_numa_running;
1126 	unsigned int		nr_preferred_running;
1127 	unsigned int		numa_migrate_on;
1128 #endif
1129 #ifdef CONFIG_NO_HZ_COMMON
1130 	unsigned long		last_blocked_load_update_tick;
1131 	unsigned int		has_blocked_load;
1132 	call_single_data_t	nohz_csd;
1133 	unsigned int		nohz_tick_stopped;
1134 	atomic_t		nohz_flags;
1135 #endif /* CONFIG_NO_HZ_COMMON */
1136 
1137 	unsigned int		ttwu_pending;
1138 	u64			nr_switches;
1139 
1140 #ifdef CONFIG_UCLAMP_TASK
1141 	/* Utilization clamp values based on CPU's RUNNABLE tasks */
1142 	struct uclamp_rq	uclamp[UCLAMP_CNT] ____cacheline_aligned;
1143 	unsigned int		uclamp_flags;
1144 #define UCLAMP_FLAG_IDLE 0x01
1145 #endif
1146 
1147 	struct cfs_rq		cfs;
1148 	struct rt_rq		rt;
1149 	struct dl_rq		dl;
1150 #ifdef CONFIG_SCHED_CLASS_EXT
1151 	struct scx_rq		scx;
1152 #endif
1153 
1154 	struct sched_dl_entity	fair_server;
1155 
1156 #ifdef CONFIG_FAIR_GROUP_SCHED
1157 	/* list of leaf cfs_rq on this CPU: */
1158 	struct list_head	leaf_cfs_rq_list;
1159 	struct list_head	*tmp_alone_branch;
1160 #endif /* CONFIG_FAIR_GROUP_SCHED */
1161 
1162 	/*
1163 	 * This is part of a global counter where only the total sum
1164 	 * over all CPUs matters. A task can increase this counter on
1165 	 * one CPU and if it got migrated afterwards it may decrease
1166 	 * it on another CPU. Always updated under the runqueue lock:
1167 	 */
1168 	unsigned long 		nr_uninterruptible;
1169 
1170 #ifdef CONFIG_SCHED_PROXY_EXEC
1171 	struct task_struct __rcu	*donor;  /* Scheduling context */
1172 	struct task_struct __rcu	*curr;   /* Execution context */
1173 #else
1174 	union {
1175 		struct task_struct __rcu *donor; /* Scheduler context */
1176 		struct task_struct __rcu *curr;  /* Execution context */
1177 	};
1178 #endif
1179 	struct sched_dl_entity	*dl_server;
1180 	struct task_struct	*idle;
1181 	struct task_struct	*stop;
1182 	unsigned long		next_balance;
1183 	struct mm_struct	*prev_mm;
1184 
1185 	unsigned int		clock_update_flags;
1186 	u64			clock;
1187 	/* Ensure that all clocks are in the same cache line */
1188 	u64			clock_task ____cacheline_aligned;
1189 	u64			clock_pelt;
1190 	unsigned long		lost_idle_time;
1191 	u64			clock_pelt_idle;
1192 	u64			clock_idle;
1193 #ifndef CONFIG_64BIT
1194 	u64			clock_pelt_idle_copy;
1195 	u64			clock_idle_copy;
1196 #endif
1197 
1198 	atomic_t		nr_iowait;
1199 
1200 	u64 last_seen_need_resched_ns;
1201 	int ticks_without_resched;
1202 
1203 #ifdef CONFIG_MEMBARRIER
1204 	int membarrier_state;
1205 #endif
1206 
1207 	struct root_domain		*rd;
1208 	struct sched_domain __rcu	*sd;
1209 
1210 	unsigned long		cpu_capacity;
1211 
1212 	struct balance_callback *balance_callback;
1213 
1214 	unsigned char		nohz_idle_balance;
1215 	unsigned char		idle_balance;
1216 
1217 	unsigned long		misfit_task_load;
1218 
1219 	/* For active balancing */
1220 	int			active_balance;
1221 	int			push_cpu;
1222 	struct cpu_stop_work	active_balance_work;
1223 
1224 	/* CPU of this runqueue: */
1225 	int			cpu;
1226 	int			online;
1227 
1228 	struct list_head cfs_tasks;
1229 
1230 	struct sched_avg	avg_rt;
1231 	struct sched_avg	avg_dl;
1232 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1233 	struct sched_avg	avg_irq;
1234 #endif
1235 #ifdef CONFIG_SCHED_HW_PRESSURE
1236 	struct sched_avg	avg_hw;
1237 #endif
1238 	u64			idle_stamp;
1239 	u64			avg_idle;
1240 
1241 	/* This is used to determine avg_idle's max value */
1242 	u64			max_idle_balance_cost;
1243 
1244 #ifdef CONFIG_HOTPLUG_CPU
1245 	struct rcuwait		hotplug_wait;
1246 #endif
1247 
1248 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1249 	u64			prev_irq_time;
1250 	u64			psi_irq_time;
1251 #endif
1252 #ifdef CONFIG_PARAVIRT
1253 	u64			prev_steal_time;
1254 #endif
1255 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1256 	u64			prev_steal_time_rq;
1257 #endif
1258 
1259 	/* calc_load related fields */
1260 	unsigned long		calc_load_update;
1261 	long			calc_load_active;
1262 
1263 #ifdef CONFIG_SCHED_HRTICK
1264 	call_single_data_t	hrtick_csd;
1265 	struct hrtimer		hrtick_timer;
1266 	ktime_t			hrtick_time;
1267 #endif
1268 
1269 #ifdef CONFIG_SCHEDSTATS
1270 	/* latency stats */
1271 	struct sched_info	rq_sched_info;
1272 	unsigned long long	rq_cpu_time;
1273 
1274 	/* sys_sched_yield() stats */
1275 	unsigned int		yld_count;
1276 
1277 	/* schedule() stats */
1278 	unsigned int		sched_count;
1279 	unsigned int		sched_goidle;
1280 
1281 	/* try_to_wake_up() stats */
1282 	unsigned int		ttwu_count;
1283 	unsigned int		ttwu_local;
1284 #endif
1285 
1286 #ifdef CONFIG_CPU_IDLE
1287 	/* Must be inspected within a RCU lock section */
1288 	struct cpuidle_state	*idle_state;
1289 #endif
1290 
1291 	unsigned int		nr_pinned;
1292 	unsigned int		push_busy;
1293 	struct cpu_stop_work	push_work;
1294 
1295 #ifdef CONFIG_SCHED_CORE
1296 	/* per rq */
1297 	struct rq		*core;
1298 	struct task_struct	*core_pick;
1299 	struct sched_dl_entity	*core_dl_server;
1300 	unsigned int		core_enabled;
1301 	unsigned int		core_sched_seq;
1302 	struct rb_root		core_tree;
1303 
1304 	/* shared state -- careful with sched_core_cpu_deactivate() */
1305 	unsigned int		core_task_seq;
1306 	unsigned int		core_pick_seq;
1307 	unsigned long		core_cookie;
1308 	unsigned int		core_forceidle_count;
1309 	unsigned int		core_forceidle_seq;
1310 	unsigned int		core_forceidle_occupation;
1311 	u64			core_forceidle_start;
1312 #endif /* CONFIG_SCHED_CORE */
1313 
1314 	/* Scratch cpumask to be temporarily used under rq_lock */
1315 	cpumask_var_t		scratch_mask;
1316 
1317 #ifdef CONFIG_CFS_BANDWIDTH
1318 	call_single_data_t	cfsb_csd;
1319 	struct list_head	cfsb_csd_list;
1320 #endif
1321 };
1322 
1323 #ifdef CONFIG_FAIR_GROUP_SCHED
1324 
1325 /* CPU runqueue to which this cfs_rq is attached */
1326 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1327 {
1328 	return cfs_rq->rq;
1329 }
1330 
1331 #else /* !CONFIG_FAIR_GROUP_SCHED: */
1332 
1333 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1334 {
1335 	return container_of(cfs_rq, struct rq, cfs);
1336 }
1337 #endif /* !CONFIG_FAIR_GROUP_SCHED */
1338 
1339 static inline int cpu_of(struct rq *rq)
1340 {
1341 	return rq->cpu;
1342 }
1343 
1344 #define MDF_PUSH		0x01
1345 
1346 static inline bool is_migration_disabled(struct task_struct *p)
1347 {
1348 	return p->migration_disabled;
1349 }
1350 
1351 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1352 
1353 #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
1354 #define this_rq()		this_cpu_ptr(&runqueues)
1355 #define task_rq(p)		cpu_rq(task_cpu(p))
1356 #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
1357 #define raw_rq()		raw_cpu_ptr(&runqueues)
1358 
1359 #ifdef CONFIG_SCHED_PROXY_EXEC
1360 static inline void rq_set_donor(struct rq *rq, struct task_struct *t)
1361 {
1362 	rcu_assign_pointer(rq->donor, t);
1363 }
1364 #else
1365 static inline void rq_set_donor(struct rq *rq, struct task_struct *t)
1366 {
1367 	/* Do nothing */
1368 }
1369 #endif
1370 
1371 #ifdef CONFIG_SCHED_CORE
1372 static inline struct cpumask *sched_group_span(struct sched_group *sg);
1373 
1374 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled);
1375 
1376 static inline bool sched_core_enabled(struct rq *rq)
1377 {
1378 	return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled;
1379 }
1380 
1381 static inline bool sched_core_disabled(void)
1382 {
1383 	return !static_branch_unlikely(&__sched_core_enabled);
1384 }
1385 
1386 /*
1387  * Be careful with this function; not for general use. The return value isn't
1388  * stable unless you actually hold a relevant rq->__lock.
1389  */
1390 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1391 {
1392 	if (sched_core_enabled(rq))
1393 		return &rq->core->__lock;
1394 
1395 	return &rq->__lock;
1396 }
1397 
1398 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1399 {
1400 	if (rq->core_enabled)
1401 		return &rq->core->__lock;
1402 
1403 	return &rq->__lock;
1404 }
1405 
1406 extern bool
1407 cfs_prio_less(const struct task_struct *a, const struct task_struct *b, bool fi);
1408 
1409 extern void task_vruntime_update(struct rq *rq, struct task_struct *p, bool in_fi);
1410 
1411 /*
1412  * Helpers to check if the CPU's core cookie matches with the task's cookie
1413  * when core scheduling is enabled.
1414  * A special case is that the task's cookie always matches with CPU's core
1415  * cookie if the CPU is in an idle core.
1416  */
1417 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1418 {
1419 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1420 	if (!sched_core_enabled(rq))
1421 		return true;
1422 
1423 	return rq->core->core_cookie == p->core_cookie;
1424 }
1425 
1426 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1427 {
1428 	bool idle_core = true;
1429 	int cpu;
1430 
1431 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1432 	if (!sched_core_enabled(rq))
1433 		return true;
1434 
1435 	for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) {
1436 		if (!available_idle_cpu(cpu)) {
1437 			idle_core = false;
1438 			break;
1439 		}
1440 	}
1441 
1442 	/*
1443 	 * A CPU in an idle core is always the best choice for tasks with
1444 	 * cookies.
1445 	 */
1446 	return idle_core || rq->core->core_cookie == p->core_cookie;
1447 }
1448 
1449 static inline bool sched_group_cookie_match(struct rq *rq,
1450 					    struct task_struct *p,
1451 					    struct sched_group *group)
1452 {
1453 	int cpu;
1454 
1455 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1456 	if (!sched_core_enabled(rq))
1457 		return true;
1458 
1459 	for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
1460 		if (sched_core_cookie_match(cpu_rq(cpu), p))
1461 			return true;
1462 	}
1463 	return false;
1464 }
1465 
1466 static inline bool sched_core_enqueued(struct task_struct *p)
1467 {
1468 	return !RB_EMPTY_NODE(&p->core_node);
1469 }
1470 
1471 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p);
1472 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags);
1473 
1474 extern void sched_core_get(void);
1475 extern void sched_core_put(void);
1476 
1477 #else /* !CONFIG_SCHED_CORE: */
1478 
1479 static inline bool sched_core_enabled(struct rq *rq)
1480 {
1481 	return false;
1482 }
1483 
1484 static inline bool sched_core_disabled(void)
1485 {
1486 	return true;
1487 }
1488 
1489 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1490 {
1491 	return &rq->__lock;
1492 }
1493 
1494 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1495 {
1496 	return &rq->__lock;
1497 }
1498 
1499 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1500 {
1501 	return true;
1502 }
1503 
1504 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1505 {
1506 	return true;
1507 }
1508 
1509 static inline bool sched_group_cookie_match(struct rq *rq,
1510 					    struct task_struct *p,
1511 					    struct sched_group *group)
1512 {
1513 	return true;
1514 }
1515 
1516 #endif /* !CONFIG_SCHED_CORE */
1517 
1518 #ifdef CONFIG_RT_GROUP_SCHED
1519 # ifdef CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED
1520 DECLARE_STATIC_KEY_FALSE(rt_group_sched);
1521 static inline bool rt_group_sched_enabled(void)
1522 {
1523 	return static_branch_unlikely(&rt_group_sched);
1524 }
1525 # else /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED: */
1526 DECLARE_STATIC_KEY_TRUE(rt_group_sched);
1527 static inline bool rt_group_sched_enabled(void)
1528 {
1529 	return static_branch_likely(&rt_group_sched);
1530 }
1531 # endif /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED */
1532 #else /* !CONFIG_RT_GROUP_SCHED: */
1533 # define rt_group_sched_enabled()	false
1534 #endif /* !CONFIG_RT_GROUP_SCHED */
1535 
1536 static inline void lockdep_assert_rq_held(struct rq *rq)
1537 {
1538 	lockdep_assert_held(__rq_lockp(rq));
1539 }
1540 
1541 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass);
1542 extern bool raw_spin_rq_trylock(struct rq *rq);
1543 extern void raw_spin_rq_unlock(struct rq *rq);
1544 
1545 static inline void raw_spin_rq_lock(struct rq *rq)
1546 {
1547 	raw_spin_rq_lock_nested(rq, 0);
1548 }
1549 
1550 static inline void raw_spin_rq_lock_irq(struct rq *rq)
1551 {
1552 	local_irq_disable();
1553 	raw_spin_rq_lock(rq);
1554 }
1555 
1556 static inline void raw_spin_rq_unlock_irq(struct rq *rq)
1557 {
1558 	raw_spin_rq_unlock(rq);
1559 	local_irq_enable();
1560 }
1561 
1562 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq)
1563 {
1564 	unsigned long flags;
1565 
1566 	local_irq_save(flags);
1567 	raw_spin_rq_lock(rq);
1568 
1569 	return flags;
1570 }
1571 
1572 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags)
1573 {
1574 	raw_spin_rq_unlock(rq);
1575 	local_irq_restore(flags);
1576 }
1577 
1578 #define raw_spin_rq_lock_irqsave(rq, flags)	\
1579 do {						\
1580 	flags = _raw_spin_rq_lock_irqsave(rq);	\
1581 } while (0)
1582 
1583 #ifdef CONFIG_SCHED_SMT
1584 extern void __update_idle_core(struct rq *rq);
1585 
1586 static inline void update_idle_core(struct rq *rq)
1587 {
1588 	if (static_branch_unlikely(&sched_smt_present))
1589 		__update_idle_core(rq);
1590 }
1591 
1592 #else /* !CONFIG_SCHED_SMT: */
1593 static inline void update_idle_core(struct rq *rq) { }
1594 #endif /* !CONFIG_SCHED_SMT */
1595 
1596 #ifdef CONFIG_FAIR_GROUP_SCHED
1597 
1598 static inline struct task_struct *task_of(struct sched_entity *se)
1599 {
1600 	WARN_ON_ONCE(!entity_is_task(se));
1601 	return container_of(se, struct task_struct, se);
1602 }
1603 
1604 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1605 {
1606 	return p->se.cfs_rq;
1607 }
1608 
1609 /* runqueue on which this entity is (to be) queued */
1610 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1611 {
1612 	return se->cfs_rq;
1613 }
1614 
1615 /* runqueue "owned" by this group */
1616 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1617 {
1618 	return grp->my_q;
1619 }
1620 
1621 #else /* !CONFIG_FAIR_GROUP_SCHED: */
1622 
1623 #define task_of(_se)		container_of(_se, struct task_struct, se)
1624 
1625 static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p)
1626 {
1627 	return &task_rq(p)->cfs;
1628 }
1629 
1630 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1631 {
1632 	const struct task_struct *p = task_of(se);
1633 	struct rq *rq = task_rq(p);
1634 
1635 	return &rq->cfs;
1636 }
1637 
1638 /* runqueue "owned" by this group */
1639 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1640 {
1641 	return NULL;
1642 }
1643 
1644 #endif /* !CONFIG_FAIR_GROUP_SCHED */
1645 
1646 extern void update_rq_clock(struct rq *rq);
1647 
1648 /*
1649  * rq::clock_update_flags bits
1650  *
1651  * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1652  *  call to __schedule(). This is an optimisation to avoid
1653  *  neighbouring rq clock updates.
1654  *
1655  * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1656  *  in effect and calls to update_rq_clock() are being ignored.
1657  *
1658  * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1659  *  made to update_rq_clock() since the last time rq::lock was pinned.
1660  *
1661  * If inside of __schedule(), clock_update_flags will have been
1662  * shifted left (a left shift is a cheap operation for the fast path
1663  * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1664  *
1665  *	if (rq-clock_update_flags >= RQCF_UPDATED)
1666  *
1667  * to check if %RQCF_UPDATED is set. It'll never be shifted more than
1668  * one position though, because the next rq_unpin_lock() will shift it
1669  * back.
1670  */
1671 #define RQCF_REQ_SKIP		0x01
1672 #define RQCF_ACT_SKIP		0x02
1673 #define RQCF_UPDATED		0x04
1674 
1675 static inline void assert_clock_updated(struct rq *rq)
1676 {
1677 	/*
1678 	 * The only reason for not seeing a clock update since the
1679 	 * last rq_pin_lock() is if we're currently skipping updates.
1680 	 */
1681 	WARN_ON_ONCE(rq->clock_update_flags < RQCF_ACT_SKIP);
1682 }
1683 
1684 static inline u64 rq_clock(struct rq *rq)
1685 {
1686 	lockdep_assert_rq_held(rq);
1687 	assert_clock_updated(rq);
1688 
1689 	return rq->clock;
1690 }
1691 
1692 static inline u64 rq_clock_task(struct rq *rq)
1693 {
1694 	lockdep_assert_rq_held(rq);
1695 	assert_clock_updated(rq);
1696 
1697 	return rq->clock_task;
1698 }
1699 
1700 static inline void rq_clock_skip_update(struct rq *rq)
1701 {
1702 	lockdep_assert_rq_held(rq);
1703 	rq->clock_update_flags |= RQCF_REQ_SKIP;
1704 }
1705 
1706 /*
1707  * See rt task throttling, which is the only time a skip
1708  * request is canceled.
1709  */
1710 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1711 {
1712 	lockdep_assert_rq_held(rq);
1713 	rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1714 }
1715 
1716 /*
1717  * During cpu offlining and rq wide unthrottling, we can trigger
1718  * an update_rq_clock() for several cfs and rt runqueues (Typically
1719  * when using list_for_each_entry_*)
1720  * rq_clock_start_loop_update() can be called after updating the clock
1721  * once and before iterating over the list to prevent multiple update.
1722  * After the iterative traversal, we need to call rq_clock_stop_loop_update()
1723  * to clear RQCF_ACT_SKIP of rq->clock_update_flags.
1724  */
1725 static inline void rq_clock_start_loop_update(struct rq *rq)
1726 {
1727 	lockdep_assert_rq_held(rq);
1728 	WARN_ON_ONCE(rq->clock_update_flags & RQCF_ACT_SKIP);
1729 	rq->clock_update_flags |= RQCF_ACT_SKIP;
1730 }
1731 
1732 static inline void rq_clock_stop_loop_update(struct rq *rq)
1733 {
1734 	lockdep_assert_rq_held(rq);
1735 	rq->clock_update_flags &= ~RQCF_ACT_SKIP;
1736 }
1737 
1738 struct rq_flags {
1739 	unsigned long flags;
1740 	struct pin_cookie cookie;
1741 	/*
1742 	 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1743 	 * current pin context is stashed here in case it needs to be
1744 	 * restored in rq_repin_lock().
1745 	 */
1746 	unsigned int clock_update_flags;
1747 };
1748 
1749 extern struct balance_callback balance_push_callback;
1750 
1751 #ifdef CONFIG_SCHED_CLASS_EXT
1752 extern const struct sched_class ext_sched_class;
1753 
1754 DECLARE_STATIC_KEY_FALSE(__scx_enabled);	/* SCX BPF scheduler loaded */
1755 DECLARE_STATIC_KEY_FALSE(__scx_switched_all);	/* all fair class tasks on SCX */
1756 
1757 #define scx_enabled()		static_branch_unlikely(&__scx_enabled)
1758 #define scx_switched_all()	static_branch_unlikely(&__scx_switched_all)
1759 
1760 static inline void scx_rq_clock_update(struct rq *rq, u64 clock)
1761 {
1762 	if (!scx_enabled())
1763 		return;
1764 	WRITE_ONCE(rq->scx.clock, clock);
1765 	smp_store_release(&rq->scx.flags, rq->scx.flags | SCX_RQ_CLK_VALID);
1766 }
1767 
1768 static inline void scx_rq_clock_invalidate(struct rq *rq)
1769 {
1770 	if (!scx_enabled())
1771 		return;
1772 	WRITE_ONCE(rq->scx.flags, rq->scx.flags & ~SCX_RQ_CLK_VALID);
1773 }
1774 
1775 #else /* !CONFIG_SCHED_CLASS_EXT: */
1776 #define scx_enabled()		false
1777 #define scx_switched_all()	false
1778 
1779 static inline void scx_rq_clock_update(struct rq *rq, u64 clock) {}
1780 static inline void scx_rq_clock_invalidate(struct rq *rq) {}
1781 #endif /* !CONFIG_SCHED_CLASS_EXT */
1782 
1783 /*
1784  * Lockdep annotation that avoids accidental unlocks; it's like a
1785  * sticky/continuous lockdep_assert_held().
1786  *
1787  * This avoids code that has access to 'struct rq *rq' (basically everything in
1788  * the scheduler) from accidentally unlocking the rq if they do not also have a
1789  * copy of the (on-stack) 'struct rq_flags rf'.
1790  *
1791  * Also see Documentation/locking/lockdep-design.rst.
1792  */
1793 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1794 {
1795 	rf->cookie = lockdep_pin_lock(__rq_lockp(rq));
1796 
1797 	rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1798 	rf->clock_update_flags = 0;
1799 	WARN_ON_ONCE(rq->balance_callback && rq->balance_callback != &balance_push_callback);
1800 }
1801 
1802 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1803 {
1804 	if (rq->clock_update_flags > RQCF_ACT_SKIP)
1805 		rf->clock_update_flags = RQCF_UPDATED;
1806 
1807 	scx_rq_clock_invalidate(rq);
1808 	lockdep_unpin_lock(__rq_lockp(rq), rf->cookie);
1809 }
1810 
1811 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1812 {
1813 	lockdep_repin_lock(__rq_lockp(rq), rf->cookie);
1814 
1815 	/*
1816 	 * Restore the value we stashed in @rf for this pin context.
1817 	 */
1818 	rq->clock_update_flags |= rf->clock_update_flags;
1819 }
1820 
1821 extern
1822 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1823 	__acquires(rq->lock);
1824 
1825 extern
1826 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1827 	__acquires(p->pi_lock)
1828 	__acquires(rq->lock);
1829 
1830 static inline void
1831 __task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1832 	__releases(rq->lock)
1833 {
1834 	rq_unpin_lock(rq, rf);
1835 	raw_spin_rq_unlock(rq);
1836 }
1837 
1838 static inline void
1839 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1840 	__releases(rq->lock)
1841 	__releases(p->pi_lock)
1842 {
1843 	__task_rq_unlock(rq, p, rf);
1844 	raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1845 }
1846 
1847 DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct,
1848 		    _T->rq = task_rq_lock(_T->lock, &_T->rf),
1849 		    task_rq_unlock(_T->rq, _T->lock, &_T->rf),
1850 		    struct rq *rq; struct rq_flags rf)
1851 
1852 DEFINE_LOCK_GUARD_1(__task_rq_lock, struct task_struct,
1853 		    _T->rq = __task_rq_lock(_T->lock, &_T->rf),
1854 		    __task_rq_unlock(_T->rq, _T->lock, &_T->rf),
1855 		    struct rq *rq; struct rq_flags rf)
1856 
1857 static inline void rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1858 	__acquires(rq->lock)
1859 {
1860 	raw_spin_rq_lock_irqsave(rq, rf->flags);
1861 	rq_pin_lock(rq, rf);
1862 }
1863 
1864 static inline void rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1865 	__acquires(rq->lock)
1866 {
1867 	raw_spin_rq_lock_irq(rq);
1868 	rq_pin_lock(rq, rf);
1869 }
1870 
1871 static inline void rq_lock(struct rq *rq, struct rq_flags *rf)
1872 	__acquires(rq->lock)
1873 {
1874 	raw_spin_rq_lock(rq);
1875 	rq_pin_lock(rq, rf);
1876 }
1877 
1878 static inline void rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1879 	__releases(rq->lock)
1880 {
1881 	rq_unpin_lock(rq, rf);
1882 	raw_spin_rq_unlock_irqrestore(rq, rf->flags);
1883 }
1884 
1885 static inline void rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1886 	__releases(rq->lock)
1887 {
1888 	rq_unpin_lock(rq, rf);
1889 	raw_spin_rq_unlock_irq(rq);
1890 }
1891 
1892 static inline void rq_unlock(struct rq *rq, struct rq_flags *rf)
1893 	__releases(rq->lock)
1894 {
1895 	rq_unpin_lock(rq, rf);
1896 	raw_spin_rq_unlock(rq);
1897 }
1898 
1899 DEFINE_LOCK_GUARD_1(rq_lock, struct rq,
1900 		    rq_lock(_T->lock, &_T->rf),
1901 		    rq_unlock(_T->lock, &_T->rf),
1902 		    struct rq_flags rf)
1903 
1904 DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq,
1905 		    rq_lock_irq(_T->lock, &_T->rf),
1906 		    rq_unlock_irq(_T->lock, &_T->rf),
1907 		    struct rq_flags rf)
1908 
1909 DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq,
1910 		    rq_lock_irqsave(_T->lock, &_T->rf),
1911 		    rq_unlock_irqrestore(_T->lock, &_T->rf),
1912 		    struct rq_flags rf)
1913 
1914 static inline struct rq *this_rq_lock_irq(struct rq_flags *rf)
1915 	__acquires(rq->lock)
1916 {
1917 	struct rq *rq;
1918 
1919 	local_irq_disable();
1920 	rq = this_rq();
1921 	rq_lock(rq, rf);
1922 
1923 	return rq;
1924 }
1925 
1926 #ifdef CONFIG_NUMA
1927 
1928 enum numa_topology_type {
1929 	NUMA_DIRECT,
1930 	NUMA_GLUELESS_MESH,
1931 	NUMA_BACKPLANE,
1932 };
1933 
1934 extern enum numa_topology_type sched_numa_topology_type;
1935 extern int sched_max_numa_distance;
1936 extern bool find_numa_distance(int distance);
1937 extern void sched_init_numa(int offline_node);
1938 extern void sched_update_numa(int cpu, bool online);
1939 extern void sched_domains_numa_masks_set(unsigned int cpu);
1940 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1941 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1942 
1943 #else /* !CONFIG_NUMA: */
1944 
1945 static inline void sched_init_numa(int offline_node) { }
1946 static inline void sched_update_numa(int cpu, bool online) { }
1947 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
1948 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1949 
1950 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1951 {
1952 	return nr_cpu_ids;
1953 }
1954 
1955 #endif /* !CONFIG_NUMA */
1956 
1957 #ifdef CONFIG_NUMA_BALANCING
1958 
1959 /* The regions in numa_faults array from task_struct */
1960 enum numa_faults_stats {
1961 	NUMA_MEM = 0,
1962 	NUMA_CPU,
1963 	NUMA_MEMBUF,
1964 	NUMA_CPUBUF
1965 };
1966 
1967 extern void sched_setnuma(struct task_struct *p, int node);
1968 extern int migrate_task_to(struct task_struct *p, int cpu);
1969 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1970 			int cpu, int scpu);
1971 extern void init_numa_balancing(u64 clone_flags, struct task_struct *p);
1972 
1973 #else /* !CONFIG_NUMA_BALANCING: */
1974 
1975 static inline void
1976 init_numa_balancing(u64 clone_flags, struct task_struct *p)
1977 {
1978 }
1979 
1980 #endif /* !CONFIG_NUMA_BALANCING */
1981 
1982 static inline void
1983 queue_balance_callback(struct rq *rq,
1984 		       struct balance_callback *head,
1985 		       void (*func)(struct rq *rq))
1986 {
1987 	lockdep_assert_rq_held(rq);
1988 
1989 	/*
1990 	 * Don't (re)queue an already queued item; nor queue anything when
1991 	 * balance_push() is active, see the comment with
1992 	 * balance_push_callback.
1993 	 */
1994 	if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
1995 		return;
1996 
1997 	head->func = func;
1998 	head->next = rq->balance_callback;
1999 	rq->balance_callback = head;
2000 }
2001 
2002 #define rcu_dereference_check_sched_domain(p) \
2003 	rcu_dereference_check((p), lockdep_is_held(&sched_domains_mutex))
2004 
2005 /*
2006  * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
2007  * See destroy_sched_domains: call_rcu for details.
2008  *
2009  * The domain tree of any CPU may only be accessed from within
2010  * preempt-disabled sections.
2011  */
2012 #define for_each_domain(cpu, __sd) \
2013 	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
2014 			__sd; __sd = __sd->parent)
2015 
2016 /* A mask of all the SD flags that have the SDF_SHARED_CHILD metaflag */
2017 #define SD_FLAG(name, mflags) (name * !!((mflags) & SDF_SHARED_CHILD)) |
2018 static const unsigned int SD_SHARED_CHILD_MASK =
2019 #include <linux/sched/sd_flags.h>
2020 0;
2021 #undef SD_FLAG
2022 
2023 /**
2024  * highest_flag_domain - Return highest sched_domain containing flag.
2025  * @cpu:	The CPU whose highest level of sched domain is to
2026  *		be returned.
2027  * @flag:	The flag to check for the highest sched_domain
2028  *		for the given CPU.
2029  *
2030  * Returns the highest sched_domain of a CPU which contains @flag. If @flag has
2031  * the SDF_SHARED_CHILD metaflag, all the children domains also have @flag.
2032  */
2033 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
2034 {
2035 	struct sched_domain *sd, *hsd = NULL;
2036 
2037 	for_each_domain(cpu, sd) {
2038 		if (sd->flags & flag) {
2039 			hsd = sd;
2040 			continue;
2041 		}
2042 
2043 		/*
2044 		 * Stop the search if @flag is known to be shared at lower
2045 		 * levels. It will not be found further up.
2046 		 */
2047 		if (flag & SD_SHARED_CHILD_MASK)
2048 			break;
2049 	}
2050 
2051 	return hsd;
2052 }
2053 
2054 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
2055 {
2056 	struct sched_domain *sd;
2057 
2058 	for_each_domain(cpu, sd) {
2059 		if (sd->flags & flag)
2060 			break;
2061 	}
2062 
2063 	return sd;
2064 }
2065 
2066 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
2067 DECLARE_PER_CPU(int, sd_llc_size);
2068 DECLARE_PER_CPU(int, sd_llc_id);
2069 DECLARE_PER_CPU(int, sd_share_id);
2070 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
2071 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
2072 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
2073 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
2074 
2075 extern struct static_key_false sched_asym_cpucapacity;
2076 extern struct static_key_false sched_cluster_active;
2077 
2078 static __always_inline bool sched_asym_cpucap_active(void)
2079 {
2080 	return static_branch_unlikely(&sched_asym_cpucapacity);
2081 }
2082 
2083 struct sched_group_capacity {
2084 	atomic_t		ref;
2085 	/*
2086 	 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
2087 	 * for a single CPU.
2088 	 */
2089 	unsigned long		capacity;
2090 	unsigned long		min_capacity;		/* Min per-CPU capacity in group */
2091 	unsigned long		max_capacity;		/* Max per-CPU capacity in group */
2092 	unsigned long		next_update;
2093 	int			imbalance;		/* XXX unrelated to capacity but shared group state */
2094 
2095 	int			id;
2096 
2097 	unsigned long		cpumask[];		/* Balance mask */
2098 };
2099 
2100 struct sched_group {
2101 	struct sched_group	*next;			/* Must be a circular list */
2102 	atomic_t		ref;
2103 
2104 	unsigned int		group_weight;
2105 	unsigned int		cores;
2106 	struct sched_group_capacity *sgc;
2107 	int			asym_prefer_cpu;	/* CPU of highest priority in group */
2108 	int			flags;
2109 
2110 	/*
2111 	 * The CPUs this group covers.
2112 	 *
2113 	 * NOTE: this field is variable length. (Allocated dynamically
2114 	 * by attaching extra space to the end of the structure,
2115 	 * depending on how many CPUs the kernel has booted up with)
2116 	 */
2117 	unsigned long		cpumask[];
2118 };
2119 
2120 static inline struct cpumask *sched_group_span(struct sched_group *sg)
2121 {
2122 	return to_cpumask(sg->cpumask);
2123 }
2124 
2125 /*
2126  * See build_balance_mask().
2127  */
2128 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
2129 {
2130 	return to_cpumask(sg->sgc->cpumask);
2131 }
2132 
2133 extern int group_balance_cpu(struct sched_group *sg);
2134 
2135 extern void update_sched_domain_debugfs(void);
2136 extern void dirty_sched_domain_sysctl(int cpu);
2137 
2138 extern int sched_update_scaling(void);
2139 
2140 static inline const struct cpumask *task_user_cpus(struct task_struct *p)
2141 {
2142 	if (!p->user_cpus_ptr)
2143 		return cpu_possible_mask; /* &init_task.cpus_mask */
2144 	return p->user_cpus_ptr;
2145 }
2146 
2147 #ifdef CONFIG_CGROUP_SCHED
2148 
2149 /*
2150  * Return the group to which this tasks belongs.
2151  *
2152  * We cannot use task_css() and friends because the cgroup subsystem
2153  * changes that value before the cgroup_subsys::attach() method is called,
2154  * therefore we cannot pin it and might observe the wrong value.
2155  *
2156  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
2157  * core changes this before calling sched_move_task().
2158  *
2159  * Instead we use a 'copy' which is updated from sched_move_task() while
2160  * holding both task_struct::pi_lock and rq::lock.
2161  */
2162 static inline struct task_group *task_group(struct task_struct *p)
2163 {
2164 	return p->sched_task_group;
2165 }
2166 
2167 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
2168 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
2169 {
2170 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
2171 	struct task_group *tg = task_group(p);
2172 #endif
2173 
2174 #ifdef CONFIG_FAIR_GROUP_SCHED
2175 	set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
2176 	p->se.cfs_rq = tg->cfs_rq[cpu];
2177 	p->se.parent = tg->se[cpu];
2178 	p->se.depth = tg->se[cpu] ? tg->se[cpu]->depth + 1 : 0;
2179 #endif
2180 
2181 #ifdef CONFIG_RT_GROUP_SCHED
2182 	/*
2183 	 * p->rt.rt_rq is NULL initially and it is easier to assign
2184 	 * root_task_group's rt_rq than switching in rt_rq_of_se()
2185 	 * Clobbers tg(!)
2186 	 */
2187 	if (!rt_group_sched_enabled())
2188 		tg = &root_task_group;
2189 	p->rt.rt_rq  = tg->rt_rq[cpu];
2190 	p->rt.parent = tg->rt_se[cpu];
2191 #endif /* CONFIG_RT_GROUP_SCHED */
2192 }
2193 
2194 #else /* !CONFIG_CGROUP_SCHED: */
2195 
2196 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
2197 
2198 static inline struct task_group *task_group(struct task_struct *p)
2199 {
2200 	return NULL;
2201 }
2202 
2203 #endif /* !CONFIG_CGROUP_SCHED */
2204 
2205 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
2206 {
2207 	set_task_rq(p, cpu);
2208 #ifdef CONFIG_SMP
2209 	/*
2210 	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
2211 	 * successfully executed on another CPU. We must ensure that updates of
2212 	 * per-task data have been completed by this moment.
2213 	 */
2214 	smp_wmb();
2215 	WRITE_ONCE(task_thread_info(p)->cpu, cpu);
2216 	p->wake_cpu = cpu;
2217 #endif /* CONFIG_SMP */
2218 }
2219 
2220 /*
2221  * Tunables:
2222  */
2223 
2224 #define SCHED_FEAT(name, enabled)	\
2225 	__SCHED_FEAT_##name ,
2226 
2227 enum {
2228 #include "features.h"
2229 	__SCHED_FEAT_NR,
2230 };
2231 
2232 #undef SCHED_FEAT
2233 
2234 /*
2235  * To support run-time toggling of sched features, all the translation units
2236  * (but core.c) reference the sysctl_sched_features defined in core.c.
2237  */
2238 extern __read_mostly unsigned int sysctl_sched_features;
2239 
2240 #ifdef CONFIG_JUMP_LABEL
2241 
2242 #define SCHED_FEAT(name, enabled)					\
2243 static __always_inline bool static_branch_##name(struct static_key *key) \
2244 {									\
2245 	return static_key_##enabled(key);				\
2246 }
2247 
2248 #include "features.h"
2249 #undef SCHED_FEAT
2250 
2251 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
2252 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
2253 
2254 #else /* !CONFIG_JUMP_LABEL: */
2255 
2256 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2257 
2258 #endif /* !CONFIG_JUMP_LABEL */
2259 
2260 extern struct static_key_false sched_numa_balancing;
2261 extern struct static_key_false sched_schedstats;
2262 
2263 static inline u64 global_rt_period(void)
2264 {
2265 	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
2266 }
2267 
2268 static inline u64 global_rt_runtime(void)
2269 {
2270 	if (sysctl_sched_rt_runtime < 0)
2271 		return RUNTIME_INF;
2272 
2273 	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
2274 }
2275 
2276 /*
2277  * Is p the current execution context?
2278  */
2279 static inline int task_current(struct rq *rq, struct task_struct *p)
2280 {
2281 	return rq->curr == p;
2282 }
2283 
2284 /*
2285  * Is p the current scheduling context?
2286  *
2287  * Note that it might be the current execution context at the same time if
2288  * rq->curr == rq->donor == p.
2289  */
2290 static inline int task_current_donor(struct rq *rq, struct task_struct *p)
2291 {
2292 	return rq->donor == p;
2293 }
2294 
2295 static inline bool task_is_blocked(struct task_struct *p)
2296 {
2297 	if (!sched_proxy_exec())
2298 		return false;
2299 
2300 	return !!p->blocked_on;
2301 }
2302 
2303 static inline int task_on_cpu(struct rq *rq, struct task_struct *p)
2304 {
2305 	return p->on_cpu;
2306 }
2307 
2308 static inline int task_on_rq_queued(struct task_struct *p)
2309 {
2310 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_QUEUED;
2311 }
2312 
2313 static inline int task_on_rq_migrating(struct task_struct *p)
2314 {
2315 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
2316 }
2317 
2318 /* Wake flags. The first three directly map to some SD flag value */
2319 #define WF_EXEC			0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
2320 #define WF_FORK			0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
2321 #define WF_TTWU			0x08 /* Wakeup;            maps to SD_BALANCE_WAKE */
2322 
2323 #define WF_SYNC			0x10 /* Waker goes to sleep after wakeup */
2324 #define WF_MIGRATED		0x20 /* Internal use, task got migrated */
2325 #define WF_CURRENT_CPU		0x40 /* Prefer to move the wakee to the current CPU. */
2326 #define WF_RQ_SELECTED		0x80 /* ->select_task_rq() was called */
2327 
2328 static_assert(WF_EXEC == SD_BALANCE_EXEC);
2329 static_assert(WF_FORK == SD_BALANCE_FORK);
2330 static_assert(WF_TTWU == SD_BALANCE_WAKE);
2331 
2332 /*
2333  * To aid in avoiding the subversion of "niceness" due to uneven distribution
2334  * of tasks with abnormal "nice" values across CPUs the contribution that
2335  * each task makes to its run queue's load is weighted according to its
2336  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
2337  * scaled version of the new time slice allocation that they receive on time
2338  * slice expiry etc.
2339  */
2340 
2341 #define WEIGHT_IDLEPRIO		3
2342 #define WMULT_IDLEPRIO		1431655765
2343 
2344 extern const int		sched_prio_to_weight[40];
2345 extern const u32		sched_prio_to_wmult[40];
2346 
2347 /*
2348  * {de,en}queue flags:
2349  *
2350  * SLEEP/WAKEUP - task is no-longer/just-became runnable
2351  *
2352  * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
2353  *                are in a known state which allows modification. Such pairs
2354  *                should preserve as much state as possible.
2355  *
2356  * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
2357  *        in the runqueue.
2358  *
2359  * NOCLOCK - skip the update_rq_clock() (avoids double updates)
2360  *
2361  * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE)
2362  *
2363  * DELAYED - de/re-queue a sched_delayed task
2364  *
2365  * CLASS - going to update p->sched_class; makes sched_change call the
2366  *         various switch methods.
2367  *
2368  * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
2369  * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
2370  * ENQUEUE_MIGRATED  - the task was migrated during wakeup
2371  * ENQUEUE_RQ_SELECTED - ->select_task_rq() was called
2372  *
2373  * XXX SAVE/RESTORE in combination with CLASS doesn't really make sense, but
2374  * SCHED_DEADLINE seems to rely on this for now.
2375  */
2376 
2377 #define DEQUEUE_SLEEP		0x0001 /* Matches ENQUEUE_WAKEUP */
2378 #define DEQUEUE_SAVE		0x0002 /* Matches ENQUEUE_RESTORE */
2379 #define DEQUEUE_MOVE		0x0004 /* Matches ENQUEUE_MOVE */
2380 #define DEQUEUE_NOCLOCK		0x0008 /* Matches ENQUEUE_NOCLOCK */
2381 
2382 #define DEQUEUE_MIGRATING	0x0010 /* Matches ENQUEUE_MIGRATING */
2383 #define DEQUEUE_DELAYED		0x0020 /* Matches ENQUEUE_DELAYED */
2384 #define DEQUEUE_CLASS		0x0040 /* Matches ENQUEUE_CLASS */
2385 
2386 #define DEQUEUE_SPECIAL		0x00010000
2387 #define DEQUEUE_THROTTLE	0x00020000
2388 
2389 #define ENQUEUE_WAKEUP		0x0001
2390 #define ENQUEUE_RESTORE		0x0002
2391 #define ENQUEUE_MOVE		0x0004
2392 #define ENQUEUE_NOCLOCK		0x0008
2393 
2394 #define ENQUEUE_MIGRATING	0x0010
2395 #define ENQUEUE_DELAYED		0x0020
2396 #define ENQUEUE_CLASS		0x0040
2397 
2398 #define ENQUEUE_HEAD		0x00010000
2399 #define ENQUEUE_REPLENISH	0x00020000
2400 #define ENQUEUE_MIGRATED	0x00040000
2401 #define ENQUEUE_INITIAL		0x00080000
2402 #define ENQUEUE_RQ_SELECTED	0x00100000
2403 
2404 #define RETRY_TASK		((void *)-1UL)
2405 
2406 struct affinity_context {
2407 	const struct cpumask	*new_mask;
2408 	struct cpumask		*user_mask;
2409 	unsigned int		flags;
2410 };
2411 
2412 extern s64 update_curr_common(struct rq *rq);
2413 
2414 struct sched_class {
2415 
2416 #ifdef CONFIG_UCLAMP_TASK
2417 	int uclamp_enabled;
2418 #endif
2419 	/*
2420 	 * idle:  0
2421 	 * ext:   1
2422 	 * fair:  2
2423 	 * rt:    4
2424 	 * dl:    8
2425 	 * stop: 16
2426 	 */
2427 	unsigned int queue_mask;
2428 
2429 	/*
2430 	 * move_queued_task/activate_task/enqueue_task: rq->lock
2431 	 * ttwu_do_activate/activate_task/enqueue_task: rq->lock
2432 	 * wake_up_new_task/activate_task/enqueue_task: task_rq_lock
2433 	 * ttwu_runnable/enqueue_task: task_rq_lock
2434 	 * proxy_task_current: rq->lock
2435 	 * sched_change_end
2436 	 */
2437 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
2438 	/*
2439 	 * move_queued_task/deactivate_task/dequeue_task: rq->lock
2440 	 * __schedule/block_task/dequeue_task: rq->lock
2441 	 * proxy_task_current: rq->lock
2442 	 * wait_task_inactive: task_rq_lock
2443 	 * sched_change_begin
2444 	 */
2445 	bool (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
2446 
2447 	/*
2448 	 * do_sched_yield: rq->lock
2449 	 */
2450 	void (*yield_task)   (struct rq *rq);
2451 	/*
2452 	 * yield_to: rq->lock (double)
2453 	 */
2454 	bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
2455 
2456 	/*
2457 	 * move_queued_task: rq->lock
2458 	 * __migrate_swap_task: rq->lock
2459 	 * ttwu_do_activate: rq->lock
2460 	 * ttwu_runnable: task_rq_lock
2461 	 * wake_up_new_task: task_rq_lock
2462 	 */
2463 	void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags);
2464 
2465 	/*
2466 	 * schedule/pick_next_task/prev_balance: rq->lock
2467 	 */
2468 	int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2469 
2470 	/*
2471 	 * schedule/pick_next_task: rq->lock
2472 	 */
2473 	struct task_struct *(*pick_task)(struct rq *rq, struct rq_flags *rf);
2474 	/*
2475 	 * Optional! When implemented pick_next_task() should be equivalent to:
2476 	 *
2477 	 *   next = pick_task();
2478 	 *   if (next) {
2479 	 *       put_prev_task(prev);
2480 	 *       set_next_task_first(next);
2481 	 *   }
2482 	 */
2483 	struct task_struct *(*pick_next_task)(struct rq *rq, struct task_struct *prev,
2484 					      struct rq_flags *rf);
2485 
2486 	/*
2487 	 * sched_change:
2488 	 * __schedule: rq->lock
2489 	 */
2490 	void (*put_prev_task)(struct rq *rq, struct task_struct *p, struct task_struct *next);
2491 	void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
2492 
2493 	/*
2494 	 * select_task_rq: p->pi_lock
2495 	 * sched_exec: p->pi_lock
2496 	 */
2497 	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
2498 
2499 	/*
2500 	 * set_task_cpu: p->pi_lock || rq->lock (ttwu like)
2501 	 */
2502 	void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
2503 
2504 	/*
2505 	 * ttwu_do_activate: rq->lock
2506 	 * wake_up_new_task: task_rq_lock
2507 	 */
2508 	void (*task_woken)(struct rq *this_rq, struct task_struct *task);
2509 
2510 	/*
2511 	 * do_set_cpus_allowed: task_rq_lock + sched_change
2512 	 */
2513 	void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx);
2514 
2515 	/*
2516 	 * sched_set_rq_{on,off}line: rq->lock
2517 	 */
2518 	void (*rq_online)(struct rq *rq);
2519 	void (*rq_offline)(struct rq *rq);
2520 
2521 	/*
2522 	 * push_cpu_stop: p->pi_lock && rq->lock
2523 	 */
2524 	struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
2525 
2526 	/*
2527 	 * hrtick: rq->lock
2528 	 * sched_tick: rq->lock
2529 	 * sched_tick_remote: rq->lock
2530 	 */
2531 	void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
2532 	/*
2533 	 * sched_cgroup_fork: p->pi_lock
2534 	 */
2535 	void (*task_fork)(struct task_struct *p);
2536 	/*
2537 	 * finish_task_switch: no locks
2538 	 */
2539 	void (*task_dead)(struct task_struct *p);
2540 
2541 	/*
2542 	 * sched_change
2543 	 */
2544 	void (*switching_from)(struct rq *this_rq, struct task_struct *task);
2545 	void (*switched_from) (struct rq *this_rq, struct task_struct *task);
2546 	void (*switching_to)  (struct rq *this_rq, struct task_struct *task);
2547 	void (*switched_to)   (struct rq *this_rq, struct task_struct *task);
2548 	u64  (*get_prio)     (struct rq *this_rq, struct task_struct *task);
2549 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
2550 			      u64 oldprio);
2551 
2552 	/*
2553 	 * set_load_weight: task_rq_lock + sched_change
2554 	 * __setscheduler_parms: task_rq_lock + sched_change
2555 	 */
2556 	void (*reweight_task)(struct rq *this_rq, struct task_struct *task,
2557 			      const struct load_weight *lw);
2558 
2559 	/*
2560 	 * sched_rr_get_interval: task_rq_lock
2561 	 */
2562 	unsigned int (*get_rr_interval)(struct rq *rq,
2563 					struct task_struct *task);
2564 
2565 	/*
2566 	 * task_sched_runtime: task_rq_lock
2567 	 */
2568 	void (*update_curr)(struct rq *rq);
2569 
2570 #ifdef CONFIG_FAIR_GROUP_SCHED
2571 	/*
2572 	 * sched_change_group: task_rq_lock + sched_change
2573 	 */
2574 	void (*task_change_group)(struct task_struct *p);
2575 #endif
2576 
2577 #ifdef CONFIG_SCHED_CORE
2578 	/*
2579 	 * pick_next_task: rq->lock
2580 	 * try_steal_cookie: rq->lock (double)
2581 	 */
2582 	int (*task_is_throttled)(struct task_struct *p, int cpu);
2583 #endif
2584 };
2585 
2586 /*
2587  * Does not nest; only used around sched_class::pick_task() rq-lock-breaks.
2588  */
2589 static inline void rq_modified_clear(struct rq *rq)
2590 {
2591 	rq->queue_mask = 0;
2592 }
2593 
2594 static inline bool rq_modified_above(struct rq *rq, const struct sched_class * class)
2595 {
2596 	unsigned int mask = class->queue_mask;
2597 	return rq->queue_mask & ~((mask << 1) - 1);
2598 }
2599 
2600 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
2601 {
2602 	WARN_ON_ONCE(rq->donor != prev);
2603 	prev->sched_class->put_prev_task(rq, prev, NULL);
2604 }
2605 
2606 static inline void set_next_task(struct rq *rq, struct task_struct *next)
2607 {
2608 	next->sched_class->set_next_task(rq, next, false);
2609 }
2610 
2611 static inline void
2612 __put_prev_set_next_dl_server(struct rq *rq,
2613 			      struct task_struct *prev,
2614 			      struct task_struct *next)
2615 {
2616 	prev->dl_server = NULL;
2617 	next->dl_server = rq->dl_server;
2618 	rq->dl_server = NULL;
2619 }
2620 
2621 static inline void put_prev_set_next_task(struct rq *rq,
2622 					  struct task_struct *prev,
2623 					  struct task_struct *next)
2624 {
2625 	WARN_ON_ONCE(rq->donor != prev);
2626 
2627 	__put_prev_set_next_dl_server(rq, prev, next);
2628 
2629 	if (next == prev)
2630 		return;
2631 
2632 	prev->sched_class->put_prev_task(rq, prev, next);
2633 	next->sched_class->set_next_task(rq, next, true);
2634 }
2635 
2636 /*
2637  * Helper to define a sched_class instance; each one is placed in a separate
2638  * section which is ordered by the linker script:
2639  *
2640  *   include/asm-generic/vmlinux.lds.h
2641  *
2642  * *CAREFUL* they are laid out in *REVERSE* order!!!
2643  *
2644  * Also enforce alignment on the instance, not the type, to guarantee layout.
2645  */
2646 #define DEFINE_SCHED_CLASS(name) \
2647 const struct sched_class name##_sched_class \
2648 	__aligned(__alignof__(struct sched_class)) \
2649 	__section("__" #name "_sched_class")
2650 
2651 /* Defined in include/asm-generic/vmlinux.lds.h */
2652 extern struct sched_class __sched_class_highest[];
2653 extern struct sched_class __sched_class_lowest[];
2654 
2655 extern const struct sched_class stop_sched_class;
2656 extern const struct sched_class dl_sched_class;
2657 extern const struct sched_class rt_sched_class;
2658 extern const struct sched_class fair_sched_class;
2659 extern const struct sched_class idle_sched_class;
2660 
2661 /*
2662  * Iterate only active classes. SCX can take over all fair tasks or be
2663  * completely disabled. If the former, skip fair. If the latter, skip SCX.
2664  */
2665 static inline const struct sched_class *next_active_class(const struct sched_class *class)
2666 {
2667 	class++;
2668 #ifdef CONFIG_SCHED_CLASS_EXT
2669 	if (scx_switched_all() && class == &fair_sched_class)
2670 		class++;
2671 	if (!scx_enabled() && class == &ext_sched_class)
2672 		class++;
2673 #endif
2674 	return class;
2675 }
2676 
2677 #define for_class_range(class, _from, _to) \
2678 	for (class = (_from); class < (_to); class++)
2679 
2680 #define for_each_class(class) \
2681 	for_class_range(class, __sched_class_highest, __sched_class_lowest)
2682 
2683 #define for_active_class_range(class, _from, _to)				\
2684 	for (class = (_from); class != (_to); class = next_active_class(class))
2685 
2686 #define for_each_active_class(class)						\
2687 	for_active_class_range(class, __sched_class_highest, __sched_class_lowest)
2688 
2689 #define sched_class_above(_a, _b)	((_a) < (_b))
2690 
2691 static inline bool sched_stop_runnable(struct rq *rq)
2692 {
2693 	return rq->stop && task_on_rq_queued(rq->stop);
2694 }
2695 
2696 static inline bool sched_dl_runnable(struct rq *rq)
2697 {
2698 	return rq->dl.dl_nr_running > 0;
2699 }
2700 
2701 static inline bool sched_rt_runnable(struct rq *rq)
2702 {
2703 	return rq->rt.rt_queued > 0;
2704 }
2705 
2706 static inline bool sched_fair_runnable(struct rq *rq)
2707 {
2708 	return rq->cfs.nr_queued > 0;
2709 }
2710 
2711 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev,
2712 					       struct rq_flags *rf);
2713 extern struct task_struct *pick_task_idle(struct rq *rq, struct rq_flags *rf);
2714 
2715 #define SCA_CHECK		0x01
2716 #define SCA_MIGRATE_DISABLE	0x02
2717 #define SCA_MIGRATE_ENABLE	0x04
2718 #define SCA_USER		0x08
2719 
2720 extern void update_group_capacity(struct sched_domain *sd, int cpu);
2721 
2722 extern void sched_balance_trigger(struct rq *rq);
2723 
2724 extern int __set_cpus_allowed_ptr(struct task_struct *p, struct affinity_context *ctx);
2725 extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx);
2726 
2727 static inline bool task_allowed_on_cpu(struct task_struct *p, int cpu)
2728 {
2729 	/* When not in the task's cpumask, no point in looking further. */
2730 	if (!cpumask_test_cpu(cpu, p->cpus_ptr))
2731 		return false;
2732 
2733 	/* Can @cpu run a user thread? */
2734 	if (!(p->flags & PF_KTHREAD) && !task_cpu_possible(cpu, p))
2735 		return false;
2736 
2737 	return true;
2738 }
2739 
2740 static inline cpumask_t *alloc_user_cpus_ptr(int node)
2741 {
2742 	/*
2743 	 * See set_cpus_allowed_force() above for the rcu_head usage.
2744 	 */
2745 	int size = max_t(int, cpumask_size(), sizeof(struct rcu_head));
2746 
2747 	return kmalloc_node(size, GFP_KERNEL, node);
2748 }
2749 
2750 static inline struct task_struct *get_push_task(struct rq *rq)
2751 {
2752 	struct task_struct *p = rq->donor;
2753 
2754 	lockdep_assert_rq_held(rq);
2755 
2756 	if (rq->push_busy)
2757 		return NULL;
2758 
2759 	if (p->nr_cpus_allowed == 1)
2760 		return NULL;
2761 
2762 	if (p->migration_disabled)
2763 		return NULL;
2764 
2765 	rq->push_busy = true;
2766 	return get_task_struct(p);
2767 }
2768 
2769 extern int push_cpu_stop(void *arg);
2770 
2771 #ifdef CONFIG_CPU_IDLE
2772 
2773 static inline void idle_set_state(struct rq *rq,
2774 				  struct cpuidle_state *idle_state)
2775 {
2776 	rq->idle_state = idle_state;
2777 }
2778 
2779 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2780 {
2781 	WARN_ON_ONCE(!rcu_read_lock_held());
2782 
2783 	return rq->idle_state;
2784 }
2785 
2786 #else /* !CONFIG_CPU_IDLE: */
2787 
2788 static inline void idle_set_state(struct rq *rq,
2789 				  struct cpuidle_state *idle_state)
2790 {
2791 }
2792 
2793 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2794 {
2795 	return NULL;
2796 }
2797 
2798 #endif /* !CONFIG_CPU_IDLE */
2799 
2800 extern void schedule_idle(void);
2801 asmlinkage void schedule_user(void);
2802 
2803 extern void sysrq_sched_debug_show(void);
2804 extern void sched_init_granularity(void);
2805 extern void update_max_interval(void);
2806 
2807 extern void init_sched_dl_class(void);
2808 extern void init_sched_rt_class(void);
2809 extern void init_sched_fair_class(void);
2810 
2811 extern void resched_curr(struct rq *rq);
2812 extern void resched_curr_lazy(struct rq *rq);
2813 extern void resched_cpu(int cpu);
2814 
2815 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
2816 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq);
2817 
2818 extern void init_dl_entity(struct sched_dl_entity *dl_se);
2819 
2820 extern void init_cfs_throttle_work(struct task_struct *p);
2821 
2822 #define BW_SHIFT		20
2823 #define BW_UNIT			(1 << BW_SHIFT)
2824 #define RATIO_SHIFT		8
2825 #define MAX_BW_BITS		(64 - BW_SHIFT)
2826 #define MAX_BW			((1ULL << MAX_BW_BITS) - 1)
2827 
2828 extern unsigned long to_ratio(u64 period, u64 runtime);
2829 
2830 extern void init_entity_runnable_average(struct sched_entity *se);
2831 extern void post_init_entity_util_avg(struct task_struct *p);
2832 
2833 #ifdef CONFIG_NO_HZ_FULL
2834 extern bool sched_can_stop_tick(struct rq *rq);
2835 extern int __init sched_tick_offload_init(void);
2836 
2837 /*
2838  * Tick may be needed by tasks in the runqueue depending on their policy and
2839  * requirements. If tick is needed, lets send the target an IPI to kick it out of
2840  * nohz mode if necessary.
2841  */
2842 static inline void sched_update_tick_dependency(struct rq *rq)
2843 {
2844 	int cpu = cpu_of(rq);
2845 
2846 	if (!tick_nohz_full_cpu(cpu))
2847 		return;
2848 
2849 	if (sched_can_stop_tick(rq))
2850 		tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
2851 	else
2852 		tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
2853 }
2854 #else /* !CONFIG_NO_HZ_FULL: */
2855 static inline int sched_tick_offload_init(void) { return 0; }
2856 static inline void sched_update_tick_dependency(struct rq *rq) { }
2857 #endif /* !CONFIG_NO_HZ_FULL */
2858 
2859 static inline void add_nr_running(struct rq *rq, unsigned count)
2860 {
2861 	unsigned prev_nr = rq->nr_running;
2862 
2863 	rq->nr_running = prev_nr + count;
2864 	if (trace_sched_update_nr_running_tp_enabled()) {
2865 		call_trace_sched_update_nr_running(rq, count);
2866 	}
2867 
2868 	if (prev_nr < 2 && rq->nr_running >= 2)
2869 		set_rd_overloaded(rq->rd, 1);
2870 
2871 	sched_update_tick_dependency(rq);
2872 }
2873 
2874 static inline void sub_nr_running(struct rq *rq, unsigned count)
2875 {
2876 	rq->nr_running -= count;
2877 	if (trace_sched_update_nr_running_tp_enabled()) {
2878 		call_trace_sched_update_nr_running(rq, -count);
2879 	}
2880 
2881 	/* Check if we still need preemption */
2882 	sched_update_tick_dependency(rq);
2883 }
2884 
2885 static inline void __block_task(struct rq *rq, struct task_struct *p)
2886 {
2887 	if (p->sched_contributes_to_load)
2888 		rq->nr_uninterruptible++;
2889 
2890 	if (p->in_iowait) {
2891 		atomic_inc(&rq->nr_iowait);
2892 		delayacct_blkio_start();
2893 	}
2894 
2895 	ASSERT_EXCLUSIVE_WRITER(p->on_rq);
2896 
2897 	/*
2898 	 * The moment this write goes through, ttwu() can swoop in and migrate
2899 	 * this task, rendering our rq->__lock ineffective.
2900 	 *
2901 	 * __schedule()				try_to_wake_up()
2902 	 *   LOCK rq->__lock			  LOCK p->pi_lock
2903 	 *   pick_next_task()
2904 	 *     pick_next_task_fair()
2905 	 *       pick_next_entity()
2906 	 *         dequeue_entities()
2907 	 *           __block_task()
2908 	 *             RELEASE p->on_rq = 0	  if (p->on_rq && ...)
2909 	 *					    break;
2910 	 *
2911 	 *					  ACQUIRE (after ctrl-dep)
2912 	 *
2913 	 *					  cpu = select_task_rq();
2914 	 *					  set_task_cpu(p, cpu);
2915 	 *					  ttwu_queue()
2916 	 *					    ttwu_do_activate()
2917 	 *					      LOCK rq->__lock
2918 	 *					      activate_task()
2919 	 *					        STORE p->on_rq = 1
2920 	 *   UNLOCK rq->__lock
2921 	 *
2922 	 * Callers must ensure to not reference @p after this -- we no longer
2923 	 * own it.
2924 	 */
2925 	smp_store_release(&p->on_rq, 0);
2926 }
2927 
2928 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
2929 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
2930 
2931 extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags);
2932 
2933 #ifdef CONFIG_PREEMPT_RT
2934 # define SCHED_NR_MIGRATE_BREAK 8
2935 #else
2936 # define SCHED_NR_MIGRATE_BREAK 32
2937 #endif
2938 
2939 extern __read_mostly unsigned int sysctl_sched_nr_migrate;
2940 extern __read_mostly unsigned int sysctl_sched_migration_cost;
2941 
2942 extern unsigned int sysctl_sched_base_slice;
2943 
2944 extern int sysctl_resched_latency_warn_ms;
2945 extern int sysctl_resched_latency_warn_once;
2946 
2947 extern unsigned int sysctl_sched_tunable_scaling;
2948 
2949 extern unsigned int sysctl_numa_balancing_scan_delay;
2950 extern unsigned int sysctl_numa_balancing_scan_period_min;
2951 extern unsigned int sysctl_numa_balancing_scan_period_max;
2952 extern unsigned int sysctl_numa_balancing_scan_size;
2953 extern unsigned int sysctl_numa_balancing_hot_threshold;
2954 
2955 #ifdef CONFIG_SCHED_HRTICK
2956 
2957 /*
2958  * Use hrtick when:
2959  *  - enabled by features
2960  *  - hrtimer is actually high res
2961  */
2962 static inline int hrtick_enabled(struct rq *rq)
2963 {
2964 	if (!cpu_active(cpu_of(rq)))
2965 		return 0;
2966 	return hrtimer_is_hres_active(&rq->hrtick_timer);
2967 }
2968 
2969 static inline int hrtick_enabled_fair(struct rq *rq)
2970 {
2971 	if (!sched_feat(HRTICK))
2972 		return 0;
2973 	return hrtick_enabled(rq);
2974 }
2975 
2976 static inline int hrtick_enabled_dl(struct rq *rq)
2977 {
2978 	if (!sched_feat(HRTICK_DL))
2979 		return 0;
2980 	return hrtick_enabled(rq);
2981 }
2982 
2983 extern void hrtick_start(struct rq *rq, u64 delay);
2984 
2985 #else /* !CONFIG_SCHED_HRTICK: */
2986 
2987 static inline int hrtick_enabled_fair(struct rq *rq)
2988 {
2989 	return 0;
2990 }
2991 
2992 static inline int hrtick_enabled_dl(struct rq *rq)
2993 {
2994 	return 0;
2995 }
2996 
2997 static inline int hrtick_enabled(struct rq *rq)
2998 {
2999 	return 0;
3000 }
3001 
3002 #endif /* !CONFIG_SCHED_HRTICK */
3003 
3004 #ifndef arch_scale_freq_tick
3005 static __always_inline void arch_scale_freq_tick(void) { }
3006 #endif
3007 
3008 #ifndef arch_scale_freq_capacity
3009 /**
3010  * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
3011  * @cpu: the CPU in question.
3012  *
3013  * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
3014  *
3015  *     f_curr
3016  *     ------ * SCHED_CAPACITY_SCALE
3017  *     f_max
3018  */
3019 static __always_inline
3020 unsigned long arch_scale_freq_capacity(int cpu)
3021 {
3022 	return SCHED_CAPACITY_SCALE;
3023 }
3024 #endif
3025 
3026 /*
3027  * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to
3028  * acquire rq lock instead of rq_lock(). So at the end of these two functions
3029  * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of
3030  * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning.
3031  */
3032 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2)
3033 {
3034 	rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
3035 	rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
3036 }
3037 
3038 #define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...)				\
3039 __DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__)			\
3040 static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2)	\
3041 { class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t;			\
3042   _lock; return _t; }
3043 
3044 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2)
3045 {
3046 #ifdef CONFIG_SCHED_CORE
3047 	/*
3048 	 * In order to not have {0,2},{1,3} turn into into an AB-BA,
3049 	 * order by core-id first and cpu-id second.
3050 	 *
3051 	 * Notably:
3052 	 *
3053 	 *	double_rq_lock(0,3); will take core-0, core-1 lock
3054 	 *	double_rq_lock(1,2); will take core-1, core-0 lock
3055 	 *
3056 	 * when only cpu-id is considered.
3057 	 */
3058 	if (rq1->core->cpu < rq2->core->cpu)
3059 		return true;
3060 	if (rq1->core->cpu > rq2->core->cpu)
3061 		return false;
3062 
3063 	/*
3064 	 * __sched_core_flip() relies on SMT having cpu-id lock order.
3065 	 */
3066 #endif /* CONFIG_SCHED_CORE */
3067 	return rq1->cpu < rq2->cpu;
3068 }
3069 
3070 extern void double_rq_lock(struct rq *rq1, struct rq *rq2);
3071 
3072 #ifdef CONFIG_PREEMPTION
3073 
3074 /*
3075  * fair double_lock_balance: Safely acquires both rq->locks in a fair
3076  * way at the expense of forcing extra atomic operations in all
3077  * invocations.  This assures that the double_lock is acquired using the
3078  * same underlying policy as the spinlock_t on this architecture, which
3079  * reduces latency compared to the unfair variant below.  However, it
3080  * also adds more overhead and therefore may reduce throughput.
3081  */
3082 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
3083 	__releases(this_rq->lock)
3084 	__acquires(busiest->lock)
3085 	__acquires(this_rq->lock)
3086 {
3087 	raw_spin_rq_unlock(this_rq);
3088 	double_rq_lock(this_rq, busiest);
3089 
3090 	return 1;
3091 }
3092 
3093 #else /* !CONFIG_PREEMPTION: */
3094 /*
3095  * Unfair double_lock_balance: Optimizes throughput at the expense of
3096  * latency by eliminating extra atomic operations when the locks are
3097  * already in proper order on entry.  This favors lower CPU-ids and will
3098  * grant the double lock to lower CPUs over higher ids under contention,
3099  * regardless of entry order into the function.
3100  */
3101 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
3102 	__releases(this_rq->lock)
3103 	__acquires(busiest->lock)
3104 	__acquires(this_rq->lock)
3105 {
3106 	if (__rq_lockp(this_rq) == __rq_lockp(busiest) ||
3107 	    likely(raw_spin_rq_trylock(busiest))) {
3108 		double_rq_clock_clear_update(this_rq, busiest);
3109 		return 0;
3110 	}
3111 
3112 	if (rq_order_less(this_rq, busiest)) {
3113 		raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING);
3114 		double_rq_clock_clear_update(this_rq, busiest);
3115 		return 0;
3116 	}
3117 
3118 	raw_spin_rq_unlock(this_rq);
3119 	double_rq_lock(this_rq, busiest);
3120 
3121 	return 1;
3122 }
3123 
3124 #endif /* !CONFIG_PREEMPTION */
3125 
3126 /*
3127  * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
3128  */
3129 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
3130 {
3131 	lockdep_assert_irqs_disabled();
3132 
3133 	return _double_lock_balance(this_rq, busiest);
3134 }
3135 
3136 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
3137 	__releases(busiest->lock)
3138 {
3139 	if (__rq_lockp(this_rq) != __rq_lockp(busiest))
3140 		raw_spin_rq_unlock(busiest);
3141 	lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_);
3142 }
3143 
3144 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
3145 {
3146 	if (l1 > l2)
3147 		swap(l1, l2);
3148 
3149 	spin_lock(l1);
3150 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3151 }
3152 
3153 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
3154 {
3155 	if (l1 > l2)
3156 		swap(l1, l2);
3157 
3158 	spin_lock_irq(l1);
3159 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3160 }
3161 
3162 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
3163 {
3164 	if (l1 > l2)
3165 		swap(l1, l2);
3166 
3167 	raw_spin_lock(l1);
3168 	raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3169 }
3170 
3171 static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2)
3172 {
3173 	raw_spin_unlock(l1);
3174 	raw_spin_unlock(l2);
3175 }
3176 
3177 DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t,
3178 		    double_raw_lock(_T->lock, _T->lock2),
3179 		    double_raw_unlock(_T->lock, _T->lock2))
3180 
3181 /*
3182  * double_rq_unlock - safely unlock two runqueues
3183  *
3184  * Note this does not restore interrupts like task_rq_unlock,
3185  * you need to do so manually after calling.
3186  */
3187 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
3188 	__releases(rq1->lock)
3189 	__releases(rq2->lock)
3190 {
3191 	if (__rq_lockp(rq1) != __rq_lockp(rq2))
3192 		raw_spin_rq_unlock(rq2);
3193 	else
3194 		__release(rq2->lock);
3195 	raw_spin_rq_unlock(rq1);
3196 }
3197 
3198 extern void set_rq_online (struct rq *rq);
3199 extern void set_rq_offline(struct rq *rq);
3200 
3201 extern bool sched_smp_initialized;
3202 
3203 DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq,
3204 		    double_rq_lock(_T->lock, _T->lock2),
3205 		    double_rq_unlock(_T->lock, _T->lock2))
3206 
3207 extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq);
3208 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
3209 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
3210 
3211 extern bool sched_debug_verbose;
3212 
3213 extern void print_cfs_stats(struct seq_file *m, int cpu);
3214 extern void print_rt_stats(struct seq_file *m, int cpu);
3215 extern void print_dl_stats(struct seq_file *m, int cpu);
3216 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
3217 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
3218 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
3219 
3220 extern void resched_latency_warn(int cpu, u64 latency);
3221 
3222 #ifdef CONFIG_NUMA_BALANCING
3223 extern void show_numa_stats(struct task_struct *p, struct seq_file *m);
3224 extern void
3225 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
3226 		 unsigned long tpf, unsigned long gsf, unsigned long gpf);
3227 #endif /* CONFIG_NUMA_BALANCING */
3228 
3229 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
3230 extern void init_rt_rq(struct rt_rq *rt_rq);
3231 extern void init_dl_rq(struct dl_rq *dl_rq);
3232 
3233 extern void cfs_bandwidth_usage_inc(void);
3234 extern void cfs_bandwidth_usage_dec(void);
3235 
3236 #ifdef CONFIG_NO_HZ_COMMON
3237 
3238 #define NOHZ_BALANCE_KICK_BIT	0
3239 #define NOHZ_STATS_KICK_BIT	1
3240 #define NOHZ_NEWILB_KICK_BIT	2
3241 #define NOHZ_NEXT_KICK_BIT	3
3242 
3243 /* Run sched_balance_domains() */
3244 #define NOHZ_BALANCE_KICK	BIT(NOHZ_BALANCE_KICK_BIT)
3245 /* Update blocked load */
3246 #define NOHZ_STATS_KICK		BIT(NOHZ_STATS_KICK_BIT)
3247 /* Update blocked load when entering idle */
3248 #define NOHZ_NEWILB_KICK	BIT(NOHZ_NEWILB_KICK_BIT)
3249 /* Update nohz.next_balance */
3250 #define NOHZ_NEXT_KICK		BIT(NOHZ_NEXT_KICK_BIT)
3251 
3252 #define NOHZ_KICK_MASK		(NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK)
3253 
3254 #define nohz_flags(cpu)		(&cpu_rq(cpu)->nohz_flags)
3255 
3256 extern void nohz_balance_exit_idle(struct rq *rq);
3257 #else /* !CONFIG_NO_HZ_COMMON: */
3258 static inline void nohz_balance_exit_idle(struct rq *rq) { }
3259 #endif /* !CONFIG_NO_HZ_COMMON */
3260 
3261 #ifdef CONFIG_NO_HZ_COMMON
3262 extern void nohz_run_idle_balance(int cpu);
3263 #else
3264 static inline void nohz_run_idle_balance(int cpu) { }
3265 #endif
3266 
3267 #include "stats.h"
3268 
3269 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS)
3270 
3271 extern void __sched_core_account_forceidle(struct rq *rq);
3272 
3273 static inline void sched_core_account_forceidle(struct rq *rq)
3274 {
3275 	if (schedstat_enabled())
3276 		__sched_core_account_forceidle(rq);
3277 }
3278 
3279 extern void __sched_core_tick(struct rq *rq);
3280 
3281 static inline void sched_core_tick(struct rq *rq)
3282 {
3283 	if (sched_core_enabled(rq) && schedstat_enabled())
3284 		__sched_core_tick(rq);
3285 }
3286 
3287 #else /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS): */
3288 
3289 static inline void sched_core_account_forceidle(struct rq *rq) { }
3290 
3291 static inline void sched_core_tick(struct rq *rq) { }
3292 
3293 #endif /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS) */
3294 
3295 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
3296 
3297 struct irqtime {
3298 	u64			total;
3299 	u64			tick_delta;
3300 	u64			irq_start_time;
3301 	struct u64_stats_sync	sync;
3302 };
3303 
3304 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
3305 extern int sched_clock_irqtime;
3306 
3307 static inline int irqtime_enabled(void)
3308 {
3309 	return sched_clock_irqtime;
3310 }
3311 
3312 /*
3313  * Returns the irqtime minus the softirq time computed by ksoftirqd.
3314  * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime
3315  * and never move forward.
3316  */
3317 static inline u64 irq_time_read(int cpu)
3318 {
3319 	struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
3320 	unsigned int seq;
3321 	u64 total;
3322 
3323 	do {
3324 		seq = __u64_stats_fetch_begin(&irqtime->sync);
3325 		total = irqtime->total;
3326 	} while (__u64_stats_fetch_retry(&irqtime->sync, seq));
3327 
3328 	return total;
3329 }
3330 
3331 #else /* !CONFIG_IRQ_TIME_ACCOUNTING: */
3332 
3333 static inline int irqtime_enabled(void)
3334 {
3335 	return 0;
3336 }
3337 
3338 #endif /* !CONFIG_IRQ_TIME_ACCOUNTING */
3339 
3340 #ifdef CONFIG_CPU_FREQ
3341 
3342 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
3343 
3344 /**
3345  * cpufreq_update_util - Take a note about CPU utilization changes.
3346  * @rq: Runqueue to carry out the update for.
3347  * @flags: Update reason flags.
3348  *
3349  * This function is called by the scheduler on the CPU whose utilization is
3350  * being updated.
3351  *
3352  * It can only be called from RCU-sched read-side critical sections.
3353  *
3354  * The way cpufreq is currently arranged requires it to evaluate the CPU
3355  * performance state (frequency/voltage) on a regular basis to prevent it from
3356  * being stuck in a completely inadequate performance level for too long.
3357  * That is not guaranteed to happen if the updates are only triggered from CFS
3358  * and DL, though, because they may not be coming in if only RT tasks are
3359  * active all the time (or there are RT tasks only).
3360  *
3361  * As a workaround for that issue, this function is called periodically by the
3362  * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
3363  * but that really is a band-aid.  Going forward it should be replaced with
3364  * solutions targeted more specifically at RT tasks.
3365  */
3366 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
3367 {
3368 	struct update_util_data *data;
3369 
3370 	data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
3371 						  cpu_of(rq)));
3372 	if (data)
3373 		data->func(data, rq_clock(rq), flags);
3374 }
3375 #else /* !CONFIG_CPU_FREQ: */
3376 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) { }
3377 #endif /* !CONFIG_CPU_FREQ */
3378 
3379 #ifdef arch_scale_freq_capacity
3380 # ifndef arch_scale_freq_invariant
3381 #  define arch_scale_freq_invariant()	true
3382 # endif
3383 #else
3384 # define arch_scale_freq_invariant()	false
3385 #endif
3386 
3387 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
3388 				 unsigned long *min,
3389 				 unsigned long *max);
3390 
3391 unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual,
3392 				 unsigned long min,
3393 				 unsigned long max);
3394 
3395 
3396 /*
3397  * Verify the fitness of task @p to run on @cpu taking into account the
3398  * CPU original capacity and the runtime/deadline ratio of the task.
3399  *
3400  * The function will return true if the original capacity of @cpu is
3401  * greater than or equal to task's deadline density right shifted by
3402  * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise.
3403  */
3404 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
3405 {
3406 	unsigned long cap = arch_scale_cpu_capacity(cpu);
3407 
3408 	return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT);
3409 }
3410 
3411 static inline unsigned long cpu_bw_dl(struct rq *rq)
3412 {
3413 	return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
3414 }
3415 
3416 static inline unsigned long cpu_util_dl(struct rq *rq)
3417 {
3418 	return READ_ONCE(rq->avg_dl.util_avg);
3419 }
3420 
3421 
3422 extern unsigned long cpu_util_cfs(int cpu);
3423 extern unsigned long cpu_util_cfs_boost(int cpu);
3424 
3425 static inline unsigned long cpu_util_rt(struct rq *rq)
3426 {
3427 	return READ_ONCE(rq->avg_rt.util_avg);
3428 }
3429 
3430 #ifdef CONFIG_UCLAMP_TASK
3431 
3432 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
3433 
3434 /*
3435  * When uclamp is compiled in, the aggregation at rq level is 'turned off'
3436  * by default in the fast path and only gets turned on once userspace performs
3437  * an operation that requires it.
3438  *
3439  * Returns true if userspace opted-in to use uclamp and aggregation at rq level
3440  * hence is active.
3441  */
3442 static inline bool uclamp_is_used(void)
3443 {
3444 	return static_branch_likely(&sched_uclamp_used);
3445 }
3446 
3447 /*
3448  * Enabling static branches would get the cpus_read_lock(),
3449  * check whether uclamp_is_used before enable it to avoid always
3450  * calling cpus_read_lock(). Because we never disable this
3451  * static key once enable it.
3452  */
3453 static inline void sched_uclamp_enable(void)
3454 {
3455 	if (!uclamp_is_used())
3456 		static_branch_enable(&sched_uclamp_used);
3457 }
3458 
3459 static inline unsigned long uclamp_rq_get(struct rq *rq,
3460 					  enum uclamp_id clamp_id)
3461 {
3462 	return READ_ONCE(rq->uclamp[clamp_id].value);
3463 }
3464 
3465 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id,
3466 				 unsigned int value)
3467 {
3468 	WRITE_ONCE(rq->uclamp[clamp_id].value, value);
3469 }
3470 
3471 static inline bool uclamp_rq_is_idle(struct rq *rq)
3472 {
3473 	return rq->uclamp_flags & UCLAMP_FLAG_IDLE;
3474 }
3475 
3476 /* Is the rq being capped/throttled by uclamp_max? */
3477 static inline bool uclamp_rq_is_capped(struct rq *rq)
3478 {
3479 	unsigned long rq_util;
3480 	unsigned long max_util;
3481 
3482 	if (!uclamp_is_used())
3483 		return false;
3484 
3485 	rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq);
3486 	max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
3487 
3488 	return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util;
3489 }
3490 
3491 #define for_each_clamp_id(clamp_id) \
3492 	for ((clamp_id) = 0; (clamp_id) < UCLAMP_CNT; (clamp_id)++)
3493 
3494 extern unsigned int sysctl_sched_uclamp_util_min_rt_default;
3495 
3496 
3497 static inline unsigned int uclamp_none(enum uclamp_id clamp_id)
3498 {
3499 	if (clamp_id == UCLAMP_MIN)
3500 		return 0;
3501 	return SCHED_CAPACITY_SCALE;
3502 }
3503 
3504 /* Integer rounded range for each bucket */
3505 #define UCLAMP_BUCKET_DELTA DIV_ROUND_CLOSEST(SCHED_CAPACITY_SCALE, UCLAMP_BUCKETS)
3506 
3507 static inline unsigned int uclamp_bucket_id(unsigned int clamp_value)
3508 {
3509 	return min_t(unsigned int, clamp_value / UCLAMP_BUCKET_DELTA, UCLAMP_BUCKETS - 1);
3510 }
3511 
3512 static inline void
3513 uclamp_se_set(struct uclamp_se *uc_se, unsigned int value, bool user_defined)
3514 {
3515 	uc_se->value = value;
3516 	uc_se->bucket_id = uclamp_bucket_id(value);
3517 	uc_se->user_defined = user_defined;
3518 }
3519 
3520 #else /* !CONFIG_UCLAMP_TASK: */
3521 
3522 static inline unsigned long
3523 uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id)
3524 {
3525 	if (clamp_id == UCLAMP_MIN)
3526 		return 0;
3527 
3528 	return SCHED_CAPACITY_SCALE;
3529 }
3530 
3531 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; }
3532 
3533 static inline bool uclamp_is_used(void)
3534 {
3535 	return false;
3536 }
3537 
3538 static inline void sched_uclamp_enable(void) {}
3539 
3540 static inline unsigned long
3541 uclamp_rq_get(struct rq *rq, enum uclamp_id clamp_id)
3542 {
3543 	if (clamp_id == UCLAMP_MIN)
3544 		return 0;
3545 
3546 	return SCHED_CAPACITY_SCALE;
3547 }
3548 
3549 static inline void
3550 uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, unsigned int value)
3551 {
3552 }
3553 
3554 static inline bool uclamp_rq_is_idle(struct rq *rq)
3555 {
3556 	return false;
3557 }
3558 
3559 #endif /* !CONFIG_UCLAMP_TASK */
3560 
3561 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
3562 
3563 static inline unsigned long cpu_util_irq(struct rq *rq)
3564 {
3565 	return READ_ONCE(rq->avg_irq.util_avg);
3566 }
3567 
3568 static inline
3569 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3570 {
3571 	util *= (max - irq);
3572 	util /= max;
3573 
3574 	return util;
3575 
3576 }
3577 
3578 #else /* !CONFIG_HAVE_SCHED_AVG_IRQ: */
3579 
3580 static inline unsigned long cpu_util_irq(struct rq *rq)
3581 {
3582 	return 0;
3583 }
3584 
3585 static inline
3586 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3587 {
3588 	return util;
3589 }
3590 
3591 #endif /* !CONFIG_HAVE_SCHED_AVG_IRQ */
3592 
3593 extern void __setparam_fair(struct task_struct *p, const struct sched_attr *attr);
3594 
3595 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
3596 
3597 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
3598 
3599 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
3600 
3601 static inline bool sched_energy_enabled(void)
3602 {
3603 	return static_branch_unlikely(&sched_energy_present);
3604 }
3605 
3606 #else /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL): */
3607 
3608 #define perf_domain_span(pd) NULL
3609 
3610 static inline bool sched_energy_enabled(void) { return false; }
3611 
3612 #endif /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
3613 
3614 #ifdef CONFIG_MEMBARRIER
3615 
3616 /*
3617  * The scheduler provides memory barriers required by membarrier between:
3618  * - prior user-space memory accesses and store to rq->membarrier_state,
3619  * - store to rq->membarrier_state and following user-space memory accesses.
3620  * In the same way it provides those guarantees around store to rq->curr.
3621  */
3622 static inline void membarrier_switch_mm(struct rq *rq,
3623 					struct mm_struct *prev_mm,
3624 					struct mm_struct *next_mm)
3625 {
3626 	int membarrier_state;
3627 
3628 	if (prev_mm == next_mm)
3629 		return;
3630 
3631 	membarrier_state = atomic_read(&next_mm->membarrier_state);
3632 	if (READ_ONCE(rq->membarrier_state) == membarrier_state)
3633 		return;
3634 
3635 	WRITE_ONCE(rq->membarrier_state, membarrier_state);
3636 }
3637 
3638 #else /* !CONFIG_MEMBARRIER: */
3639 
3640 static inline void membarrier_switch_mm(struct rq *rq,
3641 					struct mm_struct *prev_mm,
3642 					struct mm_struct *next_mm)
3643 {
3644 }
3645 
3646 #endif /* !CONFIG_MEMBARRIER */
3647 
3648 static inline bool is_per_cpu_kthread(struct task_struct *p)
3649 {
3650 	if (!(p->flags & PF_KTHREAD))
3651 		return false;
3652 
3653 	if (p->nr_cpus_allowed != 1)
3654 		return false;
3655 
3656 	return true;
3657 }
3658 
3659 extern void swake_up_all_locked(struct swait_queue_head *q);
3660 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
3661 
3662 extern int try_to_wake_up(struct task_struct *tsk, unsigned int state, int wake_flags);
3663 
3664 #ifdef CONFIG_PREEMPT_DYNAMIC
3665 extern int preempt_dynamic_mode;
3666 extern int sched_dynamic_mode(const char *str);
3667 extern void sched_dynamic_update(int mode);
3668 #endif
3669 extern const char *preempt_modes[];
3670 
3671 #ifdef CONFIG_SCHED_MM_CID
3672 
3673 #define SCHED_MM_CID_PERIOD_NS	(100ULL * 1000000)	/* 100ms */
3674 #define MM_CID_SCAN_DELAY	100			/* 100ms */
3675 
3676 extern raw_spinlock_t cid_lock;
3677 extern int use_cid_lock;
3678 
3679 extern void sched_mm_cid_migrate_from(struct task_struct *t);
3680 extern void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t);
3681 extern void task_tick_mm_cid(struct rq *rq, struct task_struct *curr);
3682 extern void init_sched_mm_cid(struct task_struct *t);
3683 
3684 static inline void __mm_cid_put(struct mm_struct *mm, int cid)
3685 {
3686 	if (cid < 0)
3687 		return;
3688 	cpumask_clear_cpu(cid, mm_cidmask(mm));
3689 }
3690 
3691 /*
3692  * The per-mm/cpu cid can have the MM_CID_LAZY_PUT flag set or transition to
3693  * the MM_CID_UNSET state without holding the rq lock, but the rq lock needs to
3694  * be held to transition to other states.
3695  *
3696  * State transitions synchronized with cmpxchg or try_cmpxchg need to be
3697  * consistent across CPUs, which prevents use of this_cpu_cmpxchg.
3698  */
3699 static inline void mm_cid_put_lazy(struct task_struct *t)
3700 {
3701 	struct mm_struct *mm = t->mm;
3702 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3703 	int cid;
3704 
3705 	lockdep_assert_irqs_disabled();
3706 	cid = __this_cpu_read(pcpu_cid->cid);
3707 	if (!mm_cid_is_lazy_put(cid) ||
3708 	    !try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET))
3709 		return;
3710 	__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3711 }
3712 
3713 static inline int mm_cid_pcpu_unset(struct mm_struct *mm)
3714 {
3715 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3716 	int cid, res;
3717 
3718 	lockdep_assert_irqs_disabled();
3719 	cid = __this_cpu_read(pcpu_cid->cid);
3720 	for (;;) {
3721 		if (mm_cid_is_unset(cid))
3722 			return MM_CID_UNSET;
3723 		/*
3724 		 * Attempt transition from valid or lazy-put to unset.
3725 		 */
3726 		res = cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, cid, MM_CID_UNSET);
3727 		if (res == cid)
3728 			break;
3729 		cid = res;
3730 	}
3731 	return cid;
3732 }
3733 
3734 static inline void mm_cid_put(struct mm_struct *mm)
3735 {
3736 	int cid;
3737 
3738 	lockdep_assert_irqs_disabled();
3739 	cid = mm_cid_pcpu_unset(mm);
3740 	if (cid == MM_CID_UNSET)
3741 		return;
3742 	__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3743 }
3744 
3745 static inline int __mm_cid_try_get(struct task_struct *t, struct mm_struct *mm)
3746 {
3747 	struct cpumask *cidmask = mm_cidmask(mm);
3748 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3749 	int cid, max_nr_cid, allowed_max_nr_cid;
3750 
3751 	/*
3752 	 * After shrinking the number of threads or reducing the number
3753 	 * of allowed cpus, reduce the value of max_nr_cid so expansion
3754 	 * of cid allocation will preserve cache locality if the number
3755 	 * of threads or allowed cpus increase again.
3756 	 */
3757 	max_nr_cid = atomic_read(&mm->max_nr_cid);
3758 	while ((allowed_max_nr_cid = min_t(int, READ_ONCE(mm->nr_cpus_allowed),
3759 					   atomic_read(&mm->mm_users))),
3760 	       max_nr_cid > allowed_max_nr_cid) {
3761 		/* atomic_try_cmpxchg loads previous mm->max_nr_cid into max_nr_cid. */
3762 		if (atomic_try_cmpxchg(&mm->max_nr_cid, &max_nr_cid, allowed_max_nr_cid)) {
3763 			max_nr_cid = allowed_max_nr_cid;
3764 			break;
3765 		}
3766 	}
3767 	/* Try to re-use recent cid. This improves cache locality. */
3768 	cid = __this_cpu_read(pcpu_cid->recent_cid);
3769 	if (!mm_cid_is_unset(cid) && cid < max_nr_cid &&
3770 	    !cpumask_test_and_set_cpu(cid, cidmask))
3771 		return cid;
3772 	/*
3773 	 * Expand cid allocation if the maximum number of concurrency
3774 	 * IDs allocated (max_nr_cid) is below the number cpus allowed
3775 	 * and number of threads. Expanding cid allocation as much as
3776 	 * possible improves cache locality.
3777 	 */
3778 	cid = max_nr_cid;
3779 	while (cid < READ_ONCE(mm->nr_cpus_allowed) && cid < atomic_read(&mm->mm_users)) {
3780 		/* atomic_try_cmpxchg loads previous mm->max_nr_cid into cid. */
3781 		if (!atomic_try_cmpxchg(&mm->max_nr_cid, &cid, cid + 1))
3782 			continue;
3783 		if (!cpumask_test_and_set_cpu(cid, cidmask))
3784 			return cid;
3785 	}
3786 	/*
3787 	 * Find the first available concurrency id.
3788 	 * Retry finding first zero bit if the mask is temporarily
3789 	 * filled. This only happens during concurrent remote-clear
3790 	 * which owns a cid without holding a rq lock.
3791 	 */
3792 	for (;;) {
3793 		cid = cpumask_first_zero(cidmask);
3794 		if (cid < READ_ONCE(mm->nr_cpus_allowed))
3795 			break;
3796 		cpu_relax();
3797 	}
3798 	if (cpumask_test_and_set_cpu(cid, cidmask))
3799 		return -1;
3800 
3801 	return cid;
3802 }
3803 
3804 /*
3805  * Save a snapshot of the current runqueue time of this cpu
3806  * with the per-cpu cid value, allowing to estimate how recently it was used.
3807  */
3808 static inline void mm_cid_snapshot_time(struct rq *rq, struct mm_struct *mm)
3809 {
3810 	struct mm_cid *pcpu_cid = per_cpu_ptr(mm->pcpu_cid, cpu_of(rq));
3811 
3812 	lockdep_assert_rq_held(rq);
3813 	WRITE_ONCE(pcpu_cid->time, rq->clock);
3814 }
3815 
3816 static inline int __mm_cid_get(struct rq *rq, struct task_struct *t,
3817 			       struct mm_struct *mm)
3818 {
3819 	int cid;
3820 
3821 	/*
3822 	 * All allocations (even those using the cid_lock) are lock-free. If
3823 	 * use_cid_lock is set, hold the cid_lock to perform cid allocation to
3824 	 * guarantee forward progress.
3825 	 */
3826 	if (!READ_ONCE(use_cid_lock)) {
3827 		cid = __mm_cid_try_get(t, mm);
3828 		if (cid >= 0)
3829 			goto end;
3830 		raw_spin_lock(&cid_lock);
3831 	} else {
3832 		raw_spin_lock(&cid_lock);
3833 		cid = __mm_cid_try_get(t, mm);
3834 		if (cid >= 0)
3835 			goto unlock;
3836 	}
3837 
3838 	/*
3839 	 * cid concurrently allocated. Retry while forcing following
3840 	 * allocations to use the cid_lock to ensure forward progress.
3841 	 */
3842 	WRITE_ONCE(use_cid_lock, 1);
3843 	/*
3844 	 * Set use_cid_lock before allocation. Only care about program order
3845 	 * because this is only required for forward progress.
3846 	 */
3847 	barrier();
3848 	/*
3849 	 * Retry until it succeeds. It is guaranteed to eventually succeed once
3850 	 * all newcoming allocations observe the use_cid_lock flag set.
3851 	 */
3852 	do {
3853 		cid = __mm_cid_try_get(t, mm);
3854 		cpu_relax();
3855 	} while (cid < 0);
3856 	/*
3857 	 * Allocate before clearing use_cid_lock. Only care about
3858 	 * program order because this is for forward progress.
3859 	 */
3860 	barrier();
3861 	WRITE_ONCE(use_cid_lock, 0);
3862 unlock:
3863 	raw_spin_unlock(&cid_lock);
3864 end:
3865 	mm_cid_snapshot_time(rq, mm);
3866 
3867 	return cid;
3868 }
3869 
3870 static inline int mm_cid_get(struct rq *rq, struct task_struct *t,
3871 			     struct mm_struct *mm)
3872 {
3873 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3874 	struct cpumask *cpumask;
3875 	int cid;
3876 
3877 	lockdep_assert_rq_held(rq);
3878 	cpumask = mm_cidmask(mm);
3879 	cid = __this_cpu_read(pcpu_cid->cid);
3880 	if (mm_cid_is_valid(cid)) {
3881 		mm_cid_snapshot_time(rq, mm);
3882 		return cid;
3883 	}
3884 	if (mm_cid_is_lazy_put(cid)) {
3885 		if (try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET))
3886 			__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3887 	}
3888 	cid = __mm_cid_get(rq, t, mm);
3889 	__this_cpu_write(pcpu_cid->cid, cid);
3890 	__this_cpu_write(pcpu_cid->recent_cid, cid);
3891 
3892 	return cid;
3893 }
3894 
3895 static inline void switch_mm_cid(struct rq *rq,
3896 				 struct task_struct *prev,
3897 				 struct task_struct *next)
3898 {
3899 	/*
3900 	 * Provide a memory barrier between rq->curr store and load of
3901 	 * {prev,next}->mm->pcpu_cid[cpu] on rq->curr->mm transition.
3902 	 *
3903 	 * Should be adapted if context_switch() is modified.
3904 	 */
3905 	if (!next->mm) {                                // to kernel
3906 		/*
3907 		 * user -> kernel transition does not guarantee a barrier, but
3908 		 * we can use the fact that it performs an atomic operation in
3909 		 * mmgrab().
3910 		 */
3911 		if (prev->mm)                           // from user
3912 			smp_mb__after_mmgrab();
3913 		/*
3914 		 * kernel -> kernel transition does not change rq->curr->mm
3915 		 * state. It stays NULL.
3916 		 */
3917 	} else {                                        // to user
3918 		/*
3919 		 * kernel -> user transition does not provide a barrier
3920 		 * between rq->curr store and load of {prev,next}->mm->pcpu_cid[cpu].
3921 		 * Provide it here.
3922 		 */
3923 		if (!prev->mm) {                        // from kernel
3924 			smp_mb();
3925 		} else {				// from user
3926 			/*
3927 			 * user->user transition relies on an implicit
3928 			 * memory barrier in switch_mm() when
3929 			 * current->mm changes. If the architecture
3930 			 * switch_mm() does not have an implicit memory
3931 			 * barrier, it is emitted here.  If current->mm
3932 			 * is unchanged, no barrier is needed.
3933 			 */
3934 			smp_mb__after_switch_mm();
3935 		}
3936 	}
3937 	if (prev->mm_cid_active) {
3938 		mm_cid_snapshot_time(rq, prev->mm);
3939 		mm_cid_put_lazy(prev);
3940 		prev->mm_cid = -1;
3941 	}
3942 	if (next->mm_cid_active)
3943 		next->last_mm_cid = next->mm_cid = mm_cid_get(rq, next, next->mm);
3944 }
3945 
3946 #else /* !CONFIG_SCHED_MM_CID: */
3947 static inline void switch_mm_cid(struct rq *rq, struct task_struct *prev, struct task_struct *next) { }
3948 static inline void sched_mm_cid_migrate_from(struct task_struct *t) { }
3949 static inline void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t) { }
3950 static inline void task_tick_mm_cid(struct rq *rq, struct task_struct *curr) { }
3951 static inline void init_sched_mm_cid(struct task_struct *t) { }
3952 #endif /* !CONFIG_SCHED_MM_CID */
3953 
3954 extern u64 avg_vruntime(struct cfs_rq *cfs_rq);
3955 extern int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se);
3956 static inline
3957 void move_queued_task_locked(struct rq *src_rq, struct rq *dst_rq, struct task_struct *task)
3958 {
3959 	lockdep_assert_rq_held(src_rq);
3960 	lockdep_assert_rq_held(dst_rq);
3961 
3962 	deactivate_task(src_rq, task, 0);
3963 	set_task_cpu(task, dst_rq->cpu);
3964 	activate_task(dst_rq, task, 0);
3965 }
3966 
3967 static inline
3968 bool task_is_pushable(struct rq *rq, struct task_struct *p, int cpu)
3969 {
3970 	if (!task_on_cpu(rq, p) &&
3971 	    cpumask_test_cpu(cpu, &p->cpus_mask))
3972 		return true;
3973 
3974 	return false;
3975 }
3976 
3977 #ifdef CONFIG_RT_MUTEXES
3978 
3979 static inline int __rt_effective_prio(struct task_struct *pi_task, int prio)
3980 {
3981 	if (pi_task)
3982 		prio = min(prio, pi_task->prio);
3983 
3984 	return prio;
3985 }
3986 
3987 static inline int rt_effective_prio(struct task_struct *p, int prio)
3988 {
3989 	struct task_struct *pi_task = rt_mutex_get_top_task(p);
3990 
3991 	return __rt_effective_prio(pi_task, prio);
3992 }
3993 
3994 #else /* !CONFIG_RT_MUTEXES: */
3995 
3996 static inline int rt_effective_prio(struct task_struct *p, int prio)
3997 {
3998 	return prio;
3999 }
4000 
4001 #endif /* !CONFIG_RT_MUTEXES */
4002 
4003 extern int __sched_setscheduler(struct task_struct *p, const struct sched_attr *attr, bool user, bool pi);
4004 extern int __sched_setaffinity(struct task_struct *p, struct affinity_context *ctx);
4005 extern const struct sched_class *__setscheduler_class(int policy, int prio);
4006 extern void set_load_weight(struct task_struct *p, bool update_load);
4007 extern void enqueue_task(struct rq *rq, struct task_struct *p, int flags);
4008 extern bool dequeue_task(struct rq *rq, struct task_struct *p, int flags);
4009 
4010 extern struct balance_callback *splice_balance_callbacks(struct rq *rq);
4011 extern void balance_callbacks(struct rq *rq, struct balance_callback *head);
4012 
4013 /*
4014  * The 'sched_change' pattern is the safe, easy and slow way of changing a
4015  * task's scheduling properties. It dequeues a task, such that the scheduler
4016  * is fully unaware of it; at which point its properties can be modified;
4017  * after which it is enqueued again.
4018  *
4019  * Typically this must be called while holding task_rq_lock, since most/all
4020  * properties are serialized under those locks. There is currently one
4021  * exception to this rule in sched/ext which only holds rq->lock.
4022  */
4023 
4024 /*
4025  * This structure is a temporary, used to preserve/convey the queueing state
4026  * of the task between sched_change_begin() and sched_change_end(). Ensuring
4027  * the task's queueing state is idempotent across the operation.
4028  */
4029 struct sched_change_ctx {
4030 	u64			prio;
4031 	struct task_struct	*p;
4032 	int			flags;
4033 	bool			queued;
4034 	bool			running;
4035 };
4036 
4037 struct sched_change_ctx *sched_change_begin(struct task_struct *p, unsigned int flags);
4038 void sched_change_end(struct sched_change_ctx *ctx);
4039 
4040 DEFINE_CLASS(sched_change, struct sched_change_ctx *,
4041 	     sched_change_end(_T),
4042 	     sched_change_begin(p, flags),
4043 	     struct task_struct *p, unsigned int flags)
4044 
4045 DEFINE_CLASS_IS_UNCONDITIONAL(sched_change)
4046 
4047 #include "ext.h"
4048 
4049 #endif /* _KERNEL_SCHED_SCHED_H */
4050