xref: /linux/kernel/sched/sched.h (revision 53439363c0a111f11625982b69c88ee2ce8608ec)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Scheduler internal types and methods:
4  */
5 #ifndef _KERNEL_SCHED_SCHED_H
6 #define _KERNEL_SCHED_SCHED_H
7 
8 #include <linux/prandom.h>
9 #include <linux/sched/affinity.h>
10 #include <linux/sched/autogroup.h>
11 #include <linux/sched/cpufreq.h>
12 #include <linux/sched/deadline.h>
13 #include <linux/sched.h>
14 #include <linux/sched/loadavg.h>
15 #include <linux/sched/mm.h>
16 #include <linux/sched/rseq_api.h>
17 #include <linux/sched/signal.h>
18 #include <linux/sched/smt.h>
19 #include <linux/sched/stat.h>
20 #include <linux/sched/sysctl.h>
21 #include <linux/sched/task_flags.h>
22 #include <linux/sched/task.h>
23 #include <linux/sched/topology.h>
24 #include <linux/atomic.h>
25 #include <linux/bitmap.h>
26 #include <linux/bug.h>
27 #include <linux/capability.h>
28 #include <linux/cgroup_api.h>
29 #include <linux/cgroup.h>
30 #include <linux/context_tracking.h>
31 #include <linux/cpufreq.h>
32 #include <linux/cpumask_api.h>
33 #include <linux/ctype.h>
34 #include <linux/file.h>
35 #include <linux/fs_api.h>
36 #include <linux/hrtimer_api.h>
37 #include <linux/interrupt.h>
38 #include <linux/irq_work.h>
39 #include <linux/jiffies.h>
40 #include <linux/kref_api.h>
41 #include <linux/kthread.h>
42 #include <linux/ktime_api.h>
43 #include <linux/lockdep_api.h>
44 #include <linux/lockdep.h>
45 #include <linux/minmax.h>
46 #include <linux/mm.h>
47 #include <linux/module.h>
48 #include <linux/mutex_api.h>
49 #include <linux/plist.h>
50 #include <linux/poll.h>
51 #include <linux/proc_fs.h>
52 #include <linux/profile.h>
53 #include <linux/psi.h>
54 #include <linux/rcupdate.h>
55 #include <linux/seq_file.h>
56 #include <linux/seqlock.h>
57 #include <linux/softirq.h>
58 #include <linux/spinlock_api.h>
59 #include <linux/static_key.h>
60 #include <linux/stop_machine.h>
61 #include <linux/syscalls_api.h>
62 #include <linux/syscalls.h>
63 #include <linux/tick.h>
64 #include <linux/topology.h>
65 #include <linux/types.h>
66 #include <linux/u64_stats_sync_api.h>
67 #include <linux/uaccess.h>
68 #include <linux/wait_api.h>
69 #include <linux/wait_bit.h>
70 #include <linux/workqueue_api.h>
71 #include <linux/delayacct.h>
72 #include <linux/mmu_context.h>
73 
74 #include <trace/events/power.h>
75 #include <trace/events/sched.h>
76 
77 #include "../workqueue_internal.h"
78 
79 struct rq;
80 struct cfs_rq;
81 struct rt_rq;
82 struct sched_group;
83 struct cpuidle_state;
84 
85 #ifdef CONFIG_PARAVIRT
86 # include <asm/paravirt.h>
87 # include <asm/paravirt_api_clock.h>
88 #endif
89 
90 #include <asm/barrier.h>
91 
92 #include "cpupri.h"
93 #include "cpudeadline.h"
94 
95 /* task_struct::on_rq states: */
96 #define TASK_ON_RQ_QUEUED	1
97 #define TASK_ON_RQ_MIGRATING	2
98 
99 extern __read_mostly int scheduler_running;
100 
101 extern unsigned long calc_load_update;
102 extern atomic_long_t calc_load_tasks;
103 
104 extern void calc_global_load_tick(struct rq *this_rq);
105 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
106 
107 extern void call_trace_sched_update_nr_running(struct rq *rq, int count);
108 
109 extern int sysctl_sched_rt_period;
110 extern int sysctl_sched_rt_runtime;
111 extern int sched_rr_timeslice;
112 
113 /*
114  * Asymmetric CPU capacity bits
115  */
116 struct asym_cap_data {
117 	struct list_head link;
118 	struct rcu_head rcu;
119 	unsigned long capacity;
120 	unsigned long cpus[];
121 };
122 
123 extern struct list_head asym_cap_list;
124 
125 #define cpu_capacity_span(asym_data) to_cpumask((asym_data)->cpus)
126 
127 /*
128  * Helpers for converting nanosecond timing to jiffy resolution
129  */
130 #define NS_TO_JIFFIES(time)	((unsigned long)(time) / (NSEC_PER_SEC/HZ))
131 
132 /*
133  * Increase resolution of nice-level calculations for 64-bit architectures.
134  * The extra resolution improves shares distribution and load balancing of
135  * low-weight task groups (eg. nice +19 on an autogroup), deeper task-group
136  * hierarchies, especially on larger systems. This is not a user-visible change
137  * and does not change the user-interface for setting shares/weights.
138  *
139  * We increase resolution only if we have enough bits to allow this increased
140  * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
141  * are pretty high and the returns do not justify the increased costs.
142  *
143  * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
144  * increase coverage and consistency always enable it on 64-bit platforms.
145  */
146 #ifdef CONFIG_64BIT
147 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
148 # define scale_load(w)		((w) << SCHED_FIXEDPOINT_SHIFT)
149 # define scale_load_down(w)					\
150 ({								\
151 	unsigned long __w = (w);				\
152 								\
153 	if (__w)						\
154 		__w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT);	\
155 	__w;							\
156 })
157 #else
158 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT)
159 # define scale_load(w)		(w)
160 # define scale_load_down(w)	(w)
161 #endif
162 
163 /*
164  * Task weight (visible to users) and its load (invisible to users) have
165  * independent resolution, but they should be well calibrated. We use
166  * scale_load() and scale_load_down(w) to convert between them. The
167  * following must be true:
168  *
169  *  scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD
170  *
171  */
172 #define NICE_0_LOAD		(1L << NICE_0_LOAD_SHIFT)
173 
174 /*
175  * Single value that decides SCHED_DEADLINE internal math precision.
176  * 10 -> just above 1us
177  * 9  -> just above 0.5us
178  */
179 #define DL_SCALE		10
180 
181 /*
182  * Single value that denotes runtime == period, ie unlimited time.
183  */
184 #define RUNTIME_INF		((u64)~0ULL)
185 
186 static inline int idle_policy(int policy)
187 {
188 	return policy == SCHED_IDLE;
189 }
190 
191 static inline int normal_policy(int policy)
192 {
193 #ifdef CONFIG_SCHED_CLASS_EXT
194 	if (policy == SCHED_EXT)
195 		return true;
196 #endif
197 	return policy == SCHED_NORMAL;
198 }
199 
200 static inline int fair_policy(int policy)
201 {
202 	return normal_policy(policy) || policy == SCHED_BATCH;
203 }
204 
205 static inline int rt_policy(int policy)
206 {
207 	return policy == SCHED_FIFO || policy == SCHED_RR;
208 }
209 
210 static inline int dl_policy(int policy)
211 {
212 	return policy == SCHED_DEADLINE;
213 }
214 
215 static inline bool valid_policy(int policy)
216 {
217 	return idle_policy(policy) || fair_policy(policy) ||
218 		rt_policy(policy) || dl_policy(policy);
219 }
220 
221 static inline int task_has_idle_policy(struct task_struct *p)
222 {
223 	return idle_policy(p->policy);
224 }
225 
226 static inline int task_has_rt_policy(struct task_struct *p)
227 {
228 	return rt_policy(p->policy);
229 }
230 
231 static inline int task_has_dl_policy(struct task_struct *p)
232 {
233 	return dl_policy(p->policy);
234 }
235 
236 #define cap_scale(v, s)		((v)*(s) >> SCHED_CAPACITY_SHIFT)
237 
238 static inline void update_avg(u64 *avg, u64 sample)
239 {
240 	s64 diff = sample - *avg;
241 
242 	*avg += diff / 8;
243 }
244 
245 /*
246  * Shifting a value by an exponent greater *or equal* to the size of said value
247  * is UB; cap at size-1.
248  */
249 #define shr_bound(val, shift)							\
250 	(val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1))
251 
252 /*
253  * cgroup weight knobs should use the common MIN, DFL and MAX values which are
254  * 1, 100 and 10000 respectively. While it loses a bit of range on both ends, it
255  * maps pretty well onto the shares value used by scheduler and the round-trip
256  * conversions preserve the original value over the entire range.
257  */
258 static inline unsigned long sched_weight_from_cgroup(unsigned long cgrp_weight)
259 {
260 	return DIV_ROUND_CLOSEST_ULL(cgrp_weight * 1024, CGROUP_WEIGHT_DFL);
261 }
262 
263 static inline unsigned long sched_weight_to_cgroup(unsigned long weight)
264 {
265 	return clamp_t(unsigned long,
266 		       DIV_ROUND_CLOSEST_ULL(weight * CGROUP_WEIGHT_DFL, 1024),
267 		       CGROUP_WEIGHT_MIN, CGROUP_WEIGHT_MAX);
268 }
269 
270 /*
271  * !! For sched_setattr_nocheck() (kernel) only !!
272  *
273  * This is actually gross. :(
274  *
275  * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
276  * tasks, but still be able to sleep. We need this on platforms that cannot
277  * atomically change clock frequency. Remove once fast switching will be
278  * available on such platforms.
279  *
280  * SUGOV stands for SchedUtil GOVernor.
281  */
282 #define SCHED_FLAG_SUGOV	0x10000000
283 
284 #define SCHED_DL_FLAGS		(SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV)
285 
286 static inline bool dl_entity_is_special(const struct sched_dl_entity *dl_se)
287 {
288 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
289 	return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
290 #else
291 	return false;
292 #endif
293 }
294 
295 /*
296  * Tells if entity @a should preempt entity @b.
297  */
298 static inline bool dl_entity_preempt(const struct sched_dl_entity *a,
299 				     const struct sched_dl_entity *b)
300 {
301 	return dl_entity_is_special(a) ||
302 	       dl_time_before(a->deadline, b->deadline);
303 }
304 
305 /*
306  * This is the priority-queue data structure of the RT scheduling class:
307  */
308 struct rt_prio_array {
309 	DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
310 	struct list_head queue[MAX_RT_PRIO];
311 };
312 
313 struct rt_bandwidth {
314 	/* nests inside the rq lock: */
315 	raw_spinlock_t		rt_runtime_lock;
316 	ktime_t			rt_period;
317 	u64			rt_runtime;
318 	struct hrtimer		rt_period_timer;
319 	unsigned int		rt_period_active;
320 };
321 
322 static inline int dl_bandwidth_enabled(void)
323 {
324 	return sysctl_sched_rt_runtime >= 0;
325 }
326 
327 /*
328  * To keep the bandwidth of -deadline tasks under control
329  * we need some place where:
330  *  - store the maximum -deadline bandwidth of each cpu;
331  *  - cache the fraction of bandwidth that is currently allocated in
332  *    each root domain;
333  *
334  * This is all done in the data structure below. It is similar to the
335  * one used for RT-throttling (rt_bandwidth), with the main difference
336  * that, since here we are only interested in admission control, we
337  * do not decrease any runtime while the group "executes", neither we
338  * need a timer to replenish it.
339  *
340  * With respect to SMP, bandwidth is given on a per root domain basis,
341  * meaning that:
342  *  - bw (< 100%) is the deadline bandwidth of each CPU;
343  *  - total_bw is the currently allocated bandwidth in each root domain;
344  */
345 struct dl_bw {
346 	raw_spinlock_t		lock;
347 	u64			bw;
348 	u64			total_bw;
349 };
350 
351 extern void init_dl_bw(struct dl_bw *dl_b);
352 extern int  sched_dl_global_validate(void);
353 extern void sched_dl_do_global(void);
354 extern int  sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
355 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
356 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
357 extern bool __checkparam_dl(const struct sched_attr *attr);
358 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
359 extern int  dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
360 extern int  dl_bw_deactivate(int cpu);
361 extern s64 dl_scaled_delta_exec(struct rq *rq, struct sched_dl_entity *dl_se, s64 delta_exec);
362 /*
363  * SCHED_DEADLINE supports servers (nested scheduling) with the following
364  * interface:
365  *
366  *   dl_se::rq -- runqueue we belong to.
367  *
368  *   dl_se::server_pick() -- nested pick_next_task(); we yield the period if this
369  *                           returns NULL.
370  *
371  *   dl_server_update() -- called from update_curr_common(), propagates runtime
372  *                         to the server.
373  *
374  *   dl_server_start() -- start the server when it has tasks; it will stop
375  *			  automatically when there are no more tasks, per
376  *			  dl_se::server_pick() returning NULL.
377  *
378  *   dl_server_stop() -- (force) stop the server; use when updating
379  *                       parameters.
380  *
381  *   dl_server_init() -- initializes the server.
382  *
383  * When started the dl_server will (per dl_defer) schedule a timer for its
384  * zero-laxity point -- that is, unlike regular EDF tasks which run ASAP, a
385  * server will run at the very end of its period.
386  *
387  * This is done such that any runtime from the target class can be accounted
388  * against the server -- through dl_server_update() above -- such that when it
389  * becomes time to run, it might already be out of runtime and get deferred
390  * until the next period. In this case dl_server_timer() will alternate
391  * between defer and replenish but never actually enqueue the server.
392  *
393  * Only when the target class does not manage to exhaust the server's runtime
394  * (there's actualy starvation in the given period), will the dl_server get on
395  * the runqueue. Once queued it will pick tasks from the target class and run
396  * them until either its runtime is exhaused, at which point its back to
397  * dl_server_timer, or until there are no more tasks to run, at which point
398  * the dl_server stops itself.
399  *
400  * By stopping at this point the dl_server retains bandwidth, which, if a new
401  * task wakes up imminently (starting the server again), can be used --
402  * subject to CBS wakeup rules -- without having to wait for the next period.
403  *
404  * Additionally, because of the dl_defer behaviour the start/stop behaviour is
405  * naturally thottled to once per period, avoiding high context switch
406  * workloads from spamming the hrtimer program/cancel paths.
407  */
408 extern void dl_server_update_idle(struct sched_dl_entity *dl_se, s64 delta_exec);
409 extern void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec);
410 extern void dl_server_start(struct sched_dl_entity *dl_se);
411 extern void dl_server_stop(struct sched_dl_entity *dl_se);
412 extern void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq,
413 		    dl_server_pick_f pick_task);
414 extern void sched_init_dl_servers(void);
415 
416 extern void fair_server_init(struct rq *rq);
417 extern void __dl_server_attach_root(struct sched_dl_entity *dl_se, struct rq *rq);
418 extern int dl_server_apply_params(struct sched_dl_entity *dl_se,
419 		    u64 runtime, u64 period, bool init);
420 
421 static inline bool dl_server_active(struct sched_dl_entity *dl_se)
422 {
423 	return dl_se->dl_server_active;
424 }
425 
426 #ifdef CONFIG_CGROUP_SCHED
427 
428 extern struct list_head task_groups;
429 
430 #ifdef CONFIG_GROUP_SCHED_BANDWIDTH
431 extern const u64 max_bw_quota_period_us;
432 
433 /*
434  * default period for group bandwidth.
435  * default: 0.1s, units: microseconds
436  */
437 static inline u64 default_bw_period_us(void)
438 {
439 	return 100000ULL;
440 }
441 #endif /* CONFIG_GROUP_SCHED_BANDWIDTH */
442 
443 struct cfs_bandwidth {
444 #ifdef CONFIG_CFS_BANDWIDTH
445 	raw_spinlock_t		lock;
446 	ktime_t			period;
447 	u64			quota;
448 	u64			runtime;
449 	u64			burst;
450 	u64			runtime_snap;
451 	s64			hierarchical_quota;
452 
453 	u8			idle;
454 	u8			period_active;
455 	u8			slack_started;
456 	struct hrtimer		period_timer;
457 	struct hrtimer		slack_timer;
458 	struct list_head	throttled_cfs_rq;
459 
460 	/* Statistics: */
461 	int			nr_periods;
462 	int			nr_throttled;
463 	int			nr_burst;
464 	u64			throttled_time;
465 	u64			burst_time;
466 #endif /* CONFIG_CFS_BANDWIDTH */
467 };
468 
469 /* Task group related information */
470 struct task_group {
471 	struct cgroup_subsys_state css;
472 
473 #ifdef CONFIG_GROUP_SCHED_WEIGHT
474 	/* A positive value indicates that this is a SCHED_IDLE group. */
475 	int			idle;
476 #endif
477 
478 #ifdef CONFIG_FAIR_GROUP_SCHED
479 	/* schedulable entities of this group on each CPU */
480 	struct sched_entity	**se;
481 	/* runqueue "owned" by this group on each CPU */
482 	struct cfs_rq		**cfs_rq;
483 	unsigned long		shares;
484 	/*
485 	 * load_avg can be heavily contended at clock tick time, so put
486 	 * it in its own cache-line separated from the fields above which
487 	 * will also be accessed at each tick.
488 	 */
489 	atomic_long_t		load_avg ____cacheline_aligned;
490 #endif /* CONFIG_FAIR_GROUP_SCHED */
491 
492 #ifdef CONFIG_RT_GROUP_SCHED
493 	struct sched_rt_entity	**rt_se;
494 	struct rt_rq		**rt_rq;
495 
496 	struct rt_bandwidth	rt_bandwidth;
497 #endif
498 
499 	struct scx_task_group	scx;
500 
501 	struct rcu_head		rcu;
502 	struct list_head	list;
503 
504 	struct task_group	*parent;
505 	struct list_head	siblings;
506 	struct list_head	children;
507 
508 #ifdef CONFIG_SCHED_AUTOGROUP
509 	struct autogroup	*autogroup;
510 #endif
511 
512 	struct cfs_bandwidth	cfs_bandwidth;
513 
514 #ifdef CONFIG_UCLAMP_TASK_GROUP
515 	/* The two decimal precision [%] value requested from user-space */
516 	unsigned int		uclamp_pct[UCLAMP_CNT];
517 	/* Clamp values requested for a task group */
518 	struct uclamp_se	uclamp_req[UCLAMP_CNT];
519 	/* Effective clamp values used for a task group */
520 	struct uclamp_se	uclamp[UCLAMP_CNT];
521 #endif
522 
523 };
524 
525 #ifdef CONFIG_GROUP_SCHED_WEIGHT
526 #define ROOT_TASK_GROUP_LOAD	NICE_0_LOAD
527 
528 /*
529  * A weight of 0 or 1 can cause arithmetics problems.
530  * A weight of a cfs_rq is the sum of weights of which entities
531  * are queued on this cfs_rq, so a weight of a entity should not be
532  * too large, so as the shares value of a task group.
533  * (The default weight is 1024 - so there's no practical
534  *  limitation from this.)
535  */
536 #define MIN_SHARES		(1UL <<  1)
537 #define MAX_SHARES		(1UL << 18)
538 #endif
539 
540 typedef int (*tg_visitor)(struct task_group *, void *);
541 
542 extern int walk_tg_tree_from(struct task_group *from,
543 			     tg_visitor down, tg_visitor up, void *data);
544 
545 /*
546  * Iterate the full tree, calling @down when first entering a node and @up when
547  * leaving it for the final time.
548  *
549  * Caller must hold rcu_lock or sufficient equivalent.
550  */
551 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
552 {
553 	return walk_tg_tree_from(&root_task_group, down, up, data);
554 }
555 
556 static inline struct task_group *css_tg(struct cgroup_subsys_state *css)
557 {
558 	return css ? container_of(css, struct task_group, css) : NULL;
559 }
560 
561 extern int tg_nop(struct task_group *tg, void *data);
562 
563 #ifdef CONFIG_FAIR_GROUP_SCHED
564 extern void free_fair_sched_group(struct task_group *tg);
565 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
566 extern void online_fair_sched_group(struct task_group *tg);
567 extern void unregister_fair_sched_group(struct task_group *tg);
568 #else /* !CONFIG_FAIR_GROUP_SCHED: */
569 static inline void free_fair_sched_group(struct task_group *tg) { }
570 static inline int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
571 {
572        return 1;
573 }
574 static inline void online_fair_sched_group(struct task_group *tg) { }
575 static inline void unregister_fair_sched_group(struct task_group *tg) { }
576 #endif /* !CONFIG_FAIR_GROUP_SCHED */
577 
578 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
579 			struct sched_entity *se, int cpu,
580 			struct sched_entity *parent);
581 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b, struct cfs_bandwidth *parent);
582 
583 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
584 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
585 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
586 extern bool cfs_task_bw_constrained(struct task_struct *p);
587 
588 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
589 		struct sched_rt_entity *rt_se, int cpu,
590 		struct sched_rt_entity *parent);
591 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
592 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
593 extern long sched_group_rt_runtime(struct task_group *tg);
594 extern long sched_group_rt_period(struct task_group *tg);
595 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
596 
597 extern struct task_group *sched_create_group(struct task_group *parent);
598 extern void sched_online_group(struct task_group *tg,
599 			       struct task_group *parent);
600 extern void sched_destroy_group(struct task_group *tg);
601 extern void sched_release_group(struct task_group *tg);
602 
603 extern void sched_move_task(struct task_struct *tsk, bool for_autogroup);
604 
605 #ifdef CONFIG_FAIR_GROUP_SCHED
606 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
607 
608 extern int sched_group_set_idle(struct task_group *tg, long idle);
609 
610 extern void set_task_rq_fair(struct sched_entity *se,
611 			     struct cfs_rq *prev, struct cfs_rq *next);
612 #else /* !CONFIG_FAIR_GROUP_SCHED: */
613 static inline int sched_group_set_shares(struct task_group *tg, unsigned long shares) { return 0; }
614 static inline int sched_group_set_idle(struct task_group *tg, long idle) { return 0; }
615 #endif /* !CONFIG_FAIR_GROUP_SCHED */
616 
617 #else /* !CONFIG_CGROUP_SCHED: */
618 
619 struct cfs_bandwidth { };
620 
621 static inline bool cfs_task_bw_constrained(struct task_struct *p) { return false; }
622 
623 #endif /* !CONFIG_CGROUP_SCHED */
624 
625 extern void unregister_rt_sched_group(struct task_group *tg);
626 extern void free_rt_sched_group(struct task_group *tg);
627 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
628 
629 /*
630  * u64_u32_load/u64_u32_store
631  *
632  * Use a copy of a u64 value to protect against data race. This is only
633  * applicable for 32-bits architectures.
634  */
635 #ifdef CONFIG_64BIT
636 # define u64_u32_load_copy(var, copy)		var
637 # define u64_u32_store_copy(var, copy, val)	(var = val)
638 #else
639 # define u64_u32_load_copy(var, copy)					\
640 ({									\
641 	u64 __val, __val_copy;						\
642 	do {								\
643 		__val_copy = copy;					\
644 		/*							\
645 		 * paired with u64_u32_store_copy(), ordering access	\
646 		 * to var and copy.					\
647 		 */							\
648 		smp_rmb();						\
649 		__val = var;						\
650 	} while (__val != __val_copy);					\
651 	__val;								\
652 })
653 # define u64_u32_store_copy(var, copy, val)				\
654 do {									\
655 	typeof(val) __val = (val);					\
656 	var = __val;							\
657 	/*								\
658 	 * paired with u64_u32_load_copy(), ordering access to var and	\
659 	 * copy.							\
660 	 */								\
661 	smp_wmb();							\
662 	copy = __val;							\
663 } while (0)
664 #endif
665 # define u64_u32_load(var)		u64_u32_load_copy(var, var##_copy)
666 # define u64_u32_store(var, val)	u64_u32_store_copy(var, var##_copy, val)
667 
668 struct balance_callback {
669 	struct balance_callback *next;
670 	void (*func)(struct rq *rq);
671 };
672 
673 /* CFS-related fields in a runqueue */
674 struct cfs_rq {
675 	struct load_weight	load;
676 	unsigned int		nr_queued;
677 	unsigned int		h_nr_queued;       /* SCHED_{NORMAL,BATCH,IDLE} */
678 	unsigned int		h_nr_runnable;     /* SCHED_{NORMAL,BATCH,IDLE} */
679 	unsigned int		h_nr_idle; /* SCHED_IDLE */
680 
681 	s64			avg_vruntime;
682 	u64			avg_load;
683 
684 	u64			zero_vruntime;
685 #ifdef CONFIG_SCHED_CORE
686 	unsigned int		forceidle_seq;
687 	u64			zero_vruntime_fi;
688 #endif
689 
690 	struct rb_root_cached	tasks_timeline;
691 
692 	/*
693 	 * 'curr' points to currently running entity on this cfs_rq.
694 	 * It is set to NULL otherwise (i.e when none are currently running).
695 	 */
696 	struct sched_entity	*curr;
697 	struct sched_entity	*next;
698 
699 	/*
700 	 * CFS load tracking
701 	 */
702 	struct sched_avg	avg;
703 #ifndef CONFIG_64BIT
704 	u64			last_update_time_copy;
705 #endif
706 	struct {
707 		raw_spinlock_t	lock ____cacheline_aligned;
708 		int		nr;
709 		unsigned long	load_avg;
710 		unsigned long	util_avg;
711 		unsigned long	runnable_avg;
712 	} removed;
713 
714 #ifdef CONFIG_FAIR_GROUP_SCHED
715 	u64			last_update_tg_load_avg;
716 	unsigned long		tg_load_avg_contrib;
717 	long			propagate;
718 	long			prop_runnable_sum;
719 
720 	/*
721 	 *   h_load = weight * f(tg)
722 	 *
723 	 * Where f(tg) is the recursive weight fraction assigned to
724 	 * this group.
725 	 */
726 	unsigned long		h_load;
727 	u64			last_h_load_update;
728 	struct sched_entity	*h_load_next;
729 #endif /* CONFIG_FAIR_GROUP_SCHED */
730 
731 #ifdef CONFIG_FAIR_GROUP_SCHED
732 	struct rq		*rq;	/* CPU runqueue to which this cfs_rq is attached */
733 
734 	/*
735 	 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
736 	 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
737 	 * (like users, containers etc.)
738 	 *
739 	 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
740 	 * This list is used during load balance.
741 	 */
742 	int			on_list;
743 	struct list_head	leaf_cfs_rq_list;
744 	struct task_group	*tg;	/* group that "owns" this runqueue */
745 
746 	/* Locally cached copy of our task_group's idle value */
747 	int			idle;
748 
749 #ifdef CONFIG_CFS_BANDWIDTH
750 	int			runtime_enabled;
751 	s64			runtime_remaining;
752 
753 	u64			throttled_pelt_idle;
754 #ifndef CONFIG_64BIT
755 	u64                     throttled_pelt_idle_copy;
756 #endif
757 	u64			throttled_clock;
758 	u64			throttled_clock_pelt;
759 	u64			throttled_clock_pelt_time;
760 	u64			throttled_clock_self;
761 	u64			throttled_clock_self_time;
762 	bool			throttled:1;
763 	bool			pelt_clock_throttled:1;
764 	int			throttle_count;
765 	struct list_head	throttled_list;
766 	struct list_head	throttled_csd_list;
767 	struct list_head        throttled_limbo_list;
768 #endif /* CONFIG_CFS_BANDWIDTH */
769 #endif /* CONFIG_FAIR_GROUP_SCHED */
770 };
771 
772 #ifdef CONFIG_SCHED_CLASS_EXT
773 /* scx_rq->flags, protected by the rq lock */
774 enum scx_rq_flags {
775 	/*
776 	 * A hotplugged CPU starts scheduling before rq_online_scx(). Track
777 	 * ops.cpu_on/offline() state so that ops.enqueue/dispatch() are called
778 	 * only while the BPF scheduler considers the CPU to be online.
779 	 */
780 	SCX_RQ_ONLINE		= 1 << 0,
781 	SCX_RQ_CAN_STOP_TICK	= 1 << 1,
782 	SCX_RQ_BAL_KEEP		= 1 << 3, /* balance decided to keep current */
783 	SCX_RQ_BYPASSING	= 1 << 4,
784 	SCX_RQ_CLK_VALID	= 1 << 5, /* RQ clock is fresh and valid */
785 	SCX_RQ_BAL_CB_PENDING	= 1 << 6, /* must queue a cb after dispatching */
786 
787 	SCX_RQ_IN_WAKEUP	= 1 << 16,
788 	SCX_RQ_IN_BALANCE	= 1 << 17,
789 };
790 
791 struct scx_rq {
792 	struct scx_dispatch_q	local_dsq;
793 	struct list_head	runnable_list;		/* runnable tasks on this rq */
794 	struct list_head	ddsp_deferred_locals;	/* deferred ddsps from enq */
795 	unsigned long		ops_qseq;
796 	u64			extra_enq_flags;	/* see move_task_to_local_dsq() */
797 	u32			nr_running;
798 	u32			cpuperf_target;		/* [0, SCHED_CAPACITY_SCALE] */
799 	bool			cpu_released;
800 	u32			flags;
801 	u64			clock;			/* current per-rq clock -- see scx_bpf_now() */
802 	cpumask_var_t		cpus_to_kick;
803 	cpumask_var_t		cpus_to_kick_if_idle;
804 	cpumask_var_t		cpus_to_preempt;
805 	cpumask_var_t		cpus_to_wait;
806 	unsigned long		kick_sync;
807 	local_t			reenq_local_deferred;
808 	struct balance_callback	deferred_bal_cb;
809 	struct irq_work		deferred_irq_work;
810 	struct irq_work		kick_cpus_irq_work;
811 	struct scx_dispatch_q	bypass_dsq;
812 };
813 #endif /* CONFIG_SCHED_CLASS_EXT */
814 
815 static inline int rt_bandwidth_enabled(void)
816 {
817 	return sysctl_sched_rt_runtime >= 0;
818 }
819 
820 /* RT IPI pull logic requires IRQ_WORK */
821 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
822 # define HAVE_RT_PUSH_IPI
823 #endif
824 
825 /* Real-Time classes' related field in a runqueue: */
826 struct rt_rq {
827 	struct rt_prio_array	active;
828 	unsigned int		rt_nr_running;
829 	unsigned int		rr_nr_running;
830 	struct {
831 		int		curr; /* highest queued rt task prio */
832 		int		next; /* next highest */
833 	} highest_prio;
834 	bool			overloaded;
835 	struct plist_head	pushable_tasks;
836 
837 	int			rt_queued;
838 
839 #ifdef CONFIG_RT_GROUP_SCHED
840 	int			rt_throttled;
841 	u64			rt_time; /* consumed RT time, goes up in update_curr_rt */
842 	u64			rt_runtime; /* allotted RT time, "slice" from rt_bandwidth, RT sharing/balancing */
843 	/* Nests inside the rq lock: */
844 	raw_spinlock_t		rt_runtime_lock;
845 
846 	unsigned int		rt_nr_boosted;
847 
848 	struct rq		*rq; /* this is always top-level rq, cache? */
849 #endif
850 #ifdef CONFIG_CGROUP_SCHED
851 	struct task_group	*tg; /* this tg has "this" rt_rq on given CPU for runnable entities */
852 #endif
853 };
854 
855 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
856 {
857 	return rt_rq->rt_queued && rt_rq->rt_nr_running;
858 }
859 
860 /* Deadline class' related fields in a runqueue */
861 struct dl_rq {
862 	/* runqueue is an rbtree, ordered by deadline */
863 	struct rb_root_cached	root;
864 
865 	unsigned int		dl_nr_running;
866 
867 	/*
868 	 * Deadline values of the currently executing and the
869 	 * earliest ready task on this rq. Caching these facilitates
870 	 * the decision whether or not a ready but not running task
871 	 * should migrate somewhere else.
872 	 */
873 	struct {
874 		u64		curr;
875 		u64		next;
876 	} earliest_dl;
877 
878 	bool			overloaded;
879 
880 	/*
881 	 * Tasks on this rq that can be pushed away. They are kept in
882 	 * an rb-tree, ordered by tasks' deadlines, with caching
883 	 * of the leftmost (earliest deadline) element.
884 	 */
885 	struct rb_root_cached	pushable_dl_tasks_root;
886 
887 	/*
888 	 * "Active utilization" for this runqueue: increased when a
889 	 * task wakes up (becomes TASK_RUNNING) and decreased when a
890 	 * task blocks
891 	 */
892 	u64			running_bw;
893 
894 	/*
895 	 * Utilization of the tasks "assigned" to this runqueue (including
896 	 * the tasks that are in runqueue and the tasks that executed on this
897 	 * CPU and blocked). Increased when a task moves to this runqueue, and
898 	 * decreased when the task moves away (migrates, changes scheduling
899 	 * policy, or terminates).
900 	 * This is needed to compute the "inactive utilization" for the
901 	 * runqueue (inactive utilization = this_bw - running_bw).
902 	 */
903 	u64			this_bw;
904 	u64			extra_bw;
905 
906 	/*
907 	 * Maximum available bandwidth for reclaiming by SCHED_FLAG_RECLAIM
908 	 * tasks of this rq. Used in calculation of reclaimable bandwidth(GRUB).
909 	 */
910 	u64			max_bw;
911 
912 	/*
913 	 * Inverse of the fraction of CPU utilization that can be reclaimed
914 	 * by the GRUB algorithm.
915 	 */
916 	u64			bw_ratio;
917 };
918 
919 #ifdef CONFIG_FAIR_GROUP_SCHED
920 
921 /* An entity is a task if it doesn't "own" a runqueue */
922 #define entity_is_task(se)	(!se->my_q)
923 
924 static inline void se_update_runnable(struct sched_entity *se)
925 {
926 	if (!entity_is_task(se))
927 		se->runnable_weight = se->my_q->h_nr_runnable;
928 }
929 
930 static inline long se_runnable(struct sched_entity *se)
931 {
932 	if (se->sched_delayed)
933 		return false;
934 
935 	if (entity_is_task(se))
936 		return !!se->on_rq;
937 	else
938 		return se->runnable_weight;
939 }
940 
941 #else /* !CONFIG_FAIR_GROUP_SCHED: */
942 
943 #define entity_is_task(se)	1
944 
945 static inline void se_update_runnable(struct sched_entity *se) { }
946 
947 static inline long se_runnable(struct sched_entity *se)
948 {
949 	if (se->sched_delayed)
950 		return false;
951 
952 	return !!se->on_rq;
953 }
954 
955 #endif /* !CONFIG_FAIR_GROUP_SCHED */
956 
957 /*
958  * XXX we want to get rid of these helpers and use the full load resolution.
959  */
960 static inline long se_weight(struct sched_entity *se)
961 {
962 	return scale_load_down(se->load.weight);
963 }
964 
965 
966 static inline bool sched_asym_prefer(int a, int b)
967 {
968 	return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
969 }
970 
971 struct perf_domain {
972 	struct em_perf_domain *em_pd;
973 	struct perf_domain *next;
974 	struct rcu_head rcu;
975 };
976 
977 /*
978  * We add the notion of a root-domain which will be used to define per-domain
979  * variables. Each exclusive cpuset essentially defines an island domain by
980  * fully partitioning the member CPUs from any other cpuset. Whenever a new
981  * exclusive cpuset is created, we also create and attach a new root-domain
982  * object.
983  *
984  */
985 struct root_domain {
986 	atomic_t		refcount;
987 	atomic_t		rto_count;
988 	struct rcu_head		rcu;
989 	cpumask_var_t		span;
990 	cpumask_var_t		online;
991 
992 	/*
993 	 * Indicate pullable load on at least one CPU, e.g:
994 	 * - More than one runnable task
995 	 * - Running task is misfit
996 	 */
997 	bool			overloaded;
998 
999 	/* Indicate one or more CPUs over-utilized (tipping point) */
1000 	bool			overutilized;
1001 
1002 	/*
1003 	 * The bit corresponding to a CPU gets set here if such CPU has more
1004 	 * than one runnable -deadline task (as it is below for RT tasks).
1005 	 */
1006 	cpumask_var_t		dlo_mask;
1007 	atomic_t		dlo_count;
1008 	struct dl_bw		dl_bw;
1009 	struct cpudl		cpudl;
1010 
1011 	/*
1012 	 * Indicate whether a root_domain's dl_bw has been checked or
1013 	 * updated. It's monotonously increasing value.
1014 	 *
1015 	 * Also, some corner cases, like 'wrap around' is dangerous, but given
1016 	 * that u64 is 'big enough'. So that shouldn't be a concern.
1017 	 */
1018 	u64 visit_cookie;
1019 
1020 #ifdef HAVE_RT_PUSH_IPI
1021 	/*
1022 	 * For IPI pull requests, loop across the rto_mask.
1023 	 */
1024 	struct irq_work		rto_push_work;
1025 	raw_spinlock_t		rto_lock;
1026 	/* These are only updated and read within rto_lock */
1027 	int			rto_loop;
1028 	int			rto_cpu;
1029 	/* These atomics are updated outside of a lock */
1030 	atomic_t		rto_loop_next;
1031 	atomic_t		rto_loop_start;
1032 #endif /* HAVE_RT_PUSH_IPI */
1033 	/*
1034 	 * The "RT overload" flag: it gets set if a CPU has more than
1035 	 * one runnable RT task.
1036 	 */
1037 	cpumask_var_t		rto_mask;
1038 	struct cpupri		cpupri;
1039 
1040 	/*
1041 	 * NULL-terminated list of performance domains intersecting with the
1042 	 * CPUs of the rd. Protected by RCU.
1043 	 */
1044 	struct perf_domain __rcu *pd;
1045 };
1046 
1047 extern void init_defrootdomain(void);
1048 extern int sched_init_domains(const struct cpumask *cpu_map);
1049 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
1050 extern void sched_get_rd(struct root_domain *rd);
1051 extern void sched_put_rd(struct root_domain *rd);
1052 
1053 static inline int get_rd_overloaded(struct root_domain *rd)
1054 {
1055 	return READ_ONCE(rd->overloaded);
1056 }
1057 
1058 static inline void set_rd_overloaded(struct root_domain *rd, int status)
1059 {
1060 	if (get_rd_overloaded(rd) != status)
1061 		WRITE_ONCE(rd->overloaded, status);
1062 }
1063 
1064 #ifdef HAVE_RT_PUSH_IPI
1065 extern void rto_push_irq_work_func(struct irq_work *work);
1066 #endif
1067 
1068 #ifdef CONFIG_UCLAMP_TASK
1069 /*
1070  * struct uclamp_bucket - Utilization clamp bucket
1071  * @value: utilization clamp value for tasks on this clamp bucket
1072  * @tasks: number of RUNNABLE tasks on this clamp bucket
1073  *
1074  * Keep track of how many tasks are RUNNABLE for a given utilization
1075  * clamp value.
1076  */
1077 struct uclamp_bucket {
1078 	unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
1079 	unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
1080 };
1081 
1082 /*
1083  * struct uclamp_rq - rq's utilization clamp
1084  * @value: currently active clamp values for a rq
1085  * @bucket: utilization clamp buckets affecting a rq
1086  *
1087  * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
1088  * A clamp value is affecting a rq when there is at least one task RUNNABLE
1089  * (or actually running) with that value.
1090  *
1091  * There are up to UCLAMP_CNT possible different clamp values, currently there
1092  * are only two: minimum utilization and maximum utilization.
1093  *
1094  * All utilization clamping values are MAX aggregated, since:
1095  * - for util_min: we want to run the CPU at least at the max of the minimum
1096  *   utilization required by its currently RUNNABLE tasks.
1097  * - for util_max: we want to allow the CPU to run up to the max of the
1098  *   maximum utilization allowed by its currently RUNNABLE tasks.
1099  *
1100  * Since on each system we expect only a limited number of different
1101  * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
1102  * the metrics required to compute all the per-rq utilization clamp values.
1103  */
1104 struct uclamp_rq {
1105 	unsigned int value;
1106 	struct uclamp_bucket bucket[UCLAMP_BUCKETS];
1107 };
1108 
1109 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
1110 #endif /* CONFIG_UCLAMP_TASK */
1111 
1112 /*
1113  * This is the main, per-CPU runqueue data structure.
1114  *
1115  * Locking rule: those places that want to lock multiple runqueues
1116  * (such as the load balancing or the thread migration code), lock
1117  * acquire operations must be ordered by ascending &runqueue.
1118  */
1119 struct rq {
1120 	/* runqueue lock: */
1121 	raw_spinlock_t		__lock;
1122 
1123 	/* Per class runqueue modification mask; bits in class order. */
1124 	unsigned int		queue_mask;
1125 	unsigned int		nr_running;
1126 #ifdef CONFIG_NUMA_BALANCING
1127 	unsigned int		nr_numa_running;
1128 	unsigned int		nr_preferred_running;
1129 	unsigned int		numa_migrate_on;
1130 #endif
1131 #ifdef CONFIG_NO_HZ_COMMON
1132 	unsigned long		last_blocked_load_update_tick;
1133 	unsigned int		has_blocked_load;
1134 	call_single_data_t	nohz_csd;
1135 	unsigned int		nohz_tick_stopped;
1136 	atomic_t		nohz_flags;
1137 #endif /* CONFIG_NO_HZ_COMMON */
1138 
1139 	unsigned int		ttwu_pending;
1140 	u64			nr_switches;
1141 
1142 #ifdef CONFIG_UCLAMP_TASK
1143 	/* Utilization clamp values based on CPU's RUNNABLE tasks */
1144 	struct uclamp_rq	uclamp[UCLAMP_CNT] ____cacheline_aligned;
1145 	unsigned int		uclamp_flags;
1146 #define UCLAMP_FLAG_IDLE 0x01
1147 #endif
1148 
1149 	struct cfs_rq		cfs;
1150 	struct rt_rq		rt;
1151 	struct dl_rq		dl;
1152 #ifdef CONFIG_SCHED_CLASS_EXT
1153 	struct scx_rq		scx;
1154 #endif
1155 
1156 	struct sched_dl_entity	fair_server;
1157 
1158 #ifdef CONFIG_FAIR_GROUP_SCHED
1159 	/* list of leaf cfs_rq on this CPU: */
1160 	struct list_head	leaf_cfs_rq_list;
1161 	struct list_head	*tmp_alone_branch;
1162 #endif /* CONFIG_FAIR_GROUP_SCHED */
1163 
1164 	/*
1165 	 * This is part of a global counter where only the total sum
1166 	 * over all CPUs matters. A task can increase this counter on
1167 	 * one CPU and if it got migrated afterwards it may decrease
1168 	 * it on another CPU. Always updated under the runqueue lock:
1169 	 */
1170 	unsigned long		nr_uninterruptible;
1171 
1172 #ifdef CONFIG_SCHED_PROXY_EXEC
1173 	struct task_struct __rcu	*donor;  /* Scheduling context */
1174 	struct task_struct __rcu	*curr;   /* Execution context */
1175 #else
1176 	union {
1177 		struct task_struct __rcu *donor; /* Scheduler context */
1178 		struct task_struct __rcu *curr;  /* Execution context */
1179 	};
1180 #endif
1181 	struct sched_dl_entity	*dl_server;
1182 	struct task_struct	*idle;
1183 	struct task_struct	*stop;
1184 	unsigned long		next_balance;
1185 	struct mm_struct	*prev_mm;
1186 
1187 	unsigned int		clock_update_flags;
1188 	u64			clock;
1189 	/* Ensure that all clocks are in the same cache line */
1190 	u64			clock_task ____cacheline_aligned;
1191 	u64			clock_pelt;
1192 	unsigned long		lost_idle_time;
1193 	u64			clock_pelt_idle;
1194 	u64			clock_idle;
1195 #ifndef CONFIG_64BIT
1196 	u64			clock_pelt_idle_copy;
1197 	u64			clock_idle_copy;
1198 #endif
1199 
1200 	atomic_t		nr_iowait;
1201 
1202 	u64 last_seen_need_resched_ns;
1203 	int ticks_without_resched;
1204 
1205 #ifdef CONFIG_MEMBARRIER
1206 	int membarrier_state;
1207 #endif
1208 
1209 	struct root_domain		*rd;
1210 	struct sched_domain __rcu	*sd;
1211 
1212 	unsigned long		cpu_capacity;
1213 
1214 	struct balance_callback *balance_callback;
1215 
1216 	unsigned char		nohz_idle_balance;
1217 	unsigned char		idle_balance;
1218 
1219 	unsigned long		misfit_task_load;
1220 
1221 	/* For active balancing */
1222 	int			active_balance;
1223 	int			push_cpu;
1224 	struct cpu_stop_work	active_balance_work;
1225 
1226 	/* CPU of this runqueue: */
1227 	int			cpu;
1228 	int			online;
1229 
1230 	struct list_head cfs_tasks;
1231 
1232 	struct sched_avg	avg_rt;
1233 	struct sched_avg	avg_dl;
1234 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1235 	struct sched_avg	avg_irq;
1236 #endif
1237 #ifdef CONFIG_SCHED_HW_PRESSURE
1238 	struct sched_avg	avg_hw;
1239 #endif
1240 	u64			idle_stamp;
1241 	u64			avg_idle;
1242 
1243 	/* This is used to determine avg_idle's max value */
1244 	u64			max_idle_balance_cost;
1245 
1246 #ifdef CONFIG_HOTPLUG_CPU
1247 	struct rcuwait		hotplug_wait;
1248 #endif
1249 
1250 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1251 	u64			prev_irq_time;
1252 	u64			psi_irq_time;
1253 #endif
1254 #ifdef CONFIG_PARAVIRT
1255 	u64			prev_steal_time;
1256 #endif
1257 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1258 	u64			prev_steal_time_rq;
1259 #endif
1260 
1261 	/* calc_load related fields */
1262 	unsigned long		calc_load_update;
1263 	long			calc_load_active;
1264 
1265 #ifdef CONFIG_SCHED_HRTICK
1266 	call_single_data_t	hrtick_csd;
1267 	struct hrtimer		hrtick_timer;
1268 	ktime_t			hrtick_time;
1269 #endif
1270 
1271 #ifdef CONFIG_SCHEDSTATS
1272 	/* latency stats */
1273 	struct sched_info	rq_sched_info;
1274 	unsigned long long	rq_cpu_time;
1275 
1276 	/* sys_sched_yield() stats */
1277 	unsigned int		yld_count;
1278 
1279 	/* schedule() stats */
1280 	unsigned int		sched_count;
1281 	unsigned int		sched_goidle;
1282 
1283 	/* try_to_wake_up() stats */
1284 	unsigned int		ttwu_count;
1285 	unsigned int		ttwu_local;
1286 #endif
1287 
1288 #ifdef CONFIG_CPU_IDLE
1289 	/* Must be inspected within a RCU lock section */
1290 	struct cpuidle_state	*idle_state;
1291 #endif
1292 
1293 	unsigned int		nr_pinned;
1294 	unsigned int		push_busy;
1295 	struct cpu_stop_work	push_work;
1296 
1297 #ifdef CONFIG_SCHED_CORE
1298 	/* per rq */
1299 	struct rq		*core;
1300 	struct task_struct	*core_pick;
1301 	struct sched_dl_entity	*core_dl_server;
1302 	unsigned int		core_enabled;
1303 	unsigned int		core_sched_seq;
1304 	struct rb_root		core_tree;
1305 
1306 	/* shared state -- careful with sched_core_cpu_deactivate() */
1307 	unsigned int		core_task_seq;
1308 	unsigned int		core_pick_seq;
1309 	unsigned long		core_cookie;
1310 	unsigned int		core_forceidle_count;
1311 	unsigned int		core_forceidle_seq;
1312 	unsigned int		core_forceidle_occupation;
1313 	u64			core_forceidle_start;
1314 #endif /* CONFIG_SCHED_CORE */
1315 
1316 	/* Scratch cpumask to be temporarily used under rq_lock */
1317 	cpumask_var_t		scratch_mask;
1318 
1319 #ifdef CONFIG_CFS_BANDWIDTH
1320 	call_single_data_t	cfsb_csd;
1321 	struct list_head	cfsb_csd_list;
1322 #endif
1323 };
1324 
1325 #ifdef CONFIG_FAIR_GROUP_SCHED
1326 
1327 /* CPU runqueue to which this cfs_rq is attached */
1328 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1329 {
1330 	return cfs_rq->rq;
1331 }
1332 
1333 #else /* !CONFIG_FAIR_GROUP_SCHED: */
1334 
1335 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1336 {
1337 	return container_of(cfs_rq, struct rq, cfs);
1338 }
1339 #endif /* !CONFIG_FAIR_GROUP_SCHED */
1340 
1341 static inline int cpu_of(struct rq *rq)
1342 {
1343 	return rq->cpu;
1344 }
1345 
1346 #define MDF_PUSH		0x01
1347 
1348 static inline bool is_migration_disabled(struct task_struct *p)
1349 {
1350 	return p->migration_disabled;
1351 }
1352 
1353 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1354 DECLARE_PER_CPU(struct rnd_state, sched_rnd_state);
1355 
1356 static inline u32 sched_rng(void)
1357 {
1358 	return prandom_u32_state(this_cpu_ptr(&sched_rnd_state));
1359 }
1360 
1361 #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
1362 #define this_rq()		this_cpu_ptr(&runqueues)
1363 #define task_rq(p)		cpu_rq(task_cpu(p))
1364 #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
1365 #define raw_rq()		raw_cpu_ptr(&runqueues)
1366 
1367 static inline bool idle_rq(struct rq *rq)
1368 {
1369 	return rq->curr == rq->idle && !rq->nr_running && !rq->ttwu_pending;
1370 }
1371 
1372 /**
1373  * available_idle_cpu - is a given CPU idle for enqueuing work.
1374  * @cpu: the CPU in question.
1375  *
1376  * Return: 1 if the CPU is currently idle. 0 otherwise.
1377  */
1378 static inline bool available_idle_cpu(int cpu)
1379 {
1380 	if (!idle_rq(cpu_rq(cpu)))
1381 		return 0;
1382 
1383 	if (vcpu_is_preempted(cpu))
1384 		return 0;
1385 
1386 	return 1;
1387 }
1388 
1389 #ifdef CONFIG_SCHED_PROXY_EXEC
1390 static inline void rq_set_donor(struct rq *rq, struct task_struct *t)
1391 {
1392 	rcu_assign_pointer(rq->donor, t);
1393 }
1394 #else
1395 static inline void rq_set_donor(struct rq *rq, struct task_struct *t)
1396 {
1397 	/* Do nothing */
1398 }
1399 #endif
1400 
1401 #ifdef CONFIG_SCHED_CORE
1402 static inline struct cpumask *sched_group_span(struct sched_group *sg);
1403 
1404 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled);
1405 
1406 static inline bool sched_core_enabled(struct rq *rq)
1407 {
1408 	return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled;
1409 }
1410 
1411 static inline bool sched_core_disabled(void)
1412 {
1413 	return !static_branch_unlikely(&__sched_core_enabled);
1414 }
1415 
1416 /*
1417  * Be careful with this function; not for general use. The return value isn't
1418  * stable unless you actually hold a relevant rq->__lock.
1419  */
1420 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1421 {
1422 	if (sched_core_enabled(rq))
1423 		return &rq->core->__lock;
1424 
1425 	return &rq->__lock;
1426 }
1427 
1428 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1429 {
1430 	if (rq->core_enabled)
1431 		return &rq->core->__lock;
1432 
1433 	return &rq->__lock;
1434 }
1435 
1436 extern bool
1437 cfs_prio_less(const struct task_struct *a, const struct task_struct *b, bool fi);
1438 
1439 extern void task_vruntime_update(struct rq *rq, struct task_struct *p, bool in_fi);
1440 
1441 /*
1442  * Helpers to check if the CPU's core cookie matches with the task's cookie
1443  * when core scheduling is enabled.
1444  * A special case is that the task's cookie always matches with CPU's core
1445  * cookie if the CPU is in an idle core.
1446  */
1447 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1448 {
1449 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1450 	if (!sched_core_enabled(rq))
1451 		return true;
1452 
1453 	return rq->core->core_cookie == p->core_cookie;
1454 }
1455 
1456 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1457 {
1458 	bool idle_core = true;
1459 	int cpu;
1460 
1461 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1462 	if (!sched_core_enabled(rq))
1463 		return true;
1464 
1465 	if (rq->core->core_cookie == p->core_cookie)
1466 		return true;
1467 
1468 	for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) {
1469 		if (!available_idle_cpu(cpu)) {
1470 			idle_core = false;
1471 			break;
1472 		}
1473 	}
1474 
1475 	/*
1476 	 * A CPU in an idle core is always the best choice for tasks with
1477 	 * cookies.
1478 	 */
1479 	return idle_core;
1480 }
1481 
1482 static inline bool sched_group_cookie_match(struct rq *rq,
1483 					    struct task_struct *p,
1484 					    struct sched_group *group)
1485 {
1486 	int cpu;
1487 
1488 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1489 	if (!sched_core_enabled(rq))
1490 		return true;
1491 
1492 	for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
1493 		if (sched_core_cookie_match(cpu_rq(cpu), p))
1494 			return true;
1495 	}
1496 	return false;
1497 }
1498 
1499 static inline bool sched_core_enqueued(struct task_struct *p)
1500 {
1501 	return !RB_EMPTY_NODE(&p->core_node);
1502 }
1503 
1504 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p);
1505 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags);
1506 
1507 extern void sched_core_get(void);
1508 extern void sched_core_put(void);
1509 
1510 #else /* !CONFIG_SCHED_CORE: */
1511 
1512 static inline bool sched_core_enabled(struct rq *rq)
1513 {
1514 	return false;
1515 }
1516 
1517 static inline bool sched_core_disabled(void)
1518 {
1519 	return true;
1520 }
1521 
1522 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1523 {
1524 	return &rq->__lock;
1525 }
1526 
1527 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1528 {
1529 	return &rq->__lock;
1530 }
1531 
1532 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1533 {
1534 	return true;
1535 }
1536 
1537 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1538 {
1539 	return true;
1540 }
1541 
1542 static inline bool sched_group_cookie_match(struct rq *rq,
1543 					    struct task_struct *p,
1544 					    struct sched_group *group)
1545 {
1546 	return true;
1547 }
1548 
1549 #endif /* !CONFIG_SCHED_CORE */
1550 
1551 #ifdef CONFIG_RT_GROUP_SCHED
1552 # ifdef CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED
1553 DECLARE_STATIC_KEY_FALSE(rt_group_sched);
1554 static inline bool rt_group_sched_enabled(void)
1555 {
1556 	return static_branch_unlikely(&rt_group_sched);
1557 }
1558 # else /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED: */
1559 DECLARE_STATIC_KEY_TRUE(rt_group_sched);
1560 static inline bool rt_group_sched_enabled(void)
1561 {
1562 	return static_branch_likely(&rt_group_sched);
1563 }
1564 # endif /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED */
1565 #else /* !CONFIG_RT_GROUP_SCHED: */
1566 # define rt_group_sched_enabled()	false
1567 #endif /* !CONFIG_RT_GROUP_SCHED */
1568 
1569 static inline void lockdep_assert_rq_held(struct rq *rq)
1570 {
1571 	lockdep_assert_held(__rq_lockp(rq));
1572 }
1573 
1574 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass);
1575 extern bool raw_spin_rq_trylock(struct rq *rq);
1576 extern void raw_spin_rq_unlock(struct rq *rq);
1577 
1578 static inline void raw_spin_rq_lock(struct rq *rq)
1579 {
1580 	raw_spin_rq_lock_nested(rq, 0);
1581 }
1582 
1583 static inline void raw_spin_rq_lock_irq(struct rq *rq)
1584 {
1585 	local_irq_disable();
1586 	raw_spin_rq_lock(rq);
1587 }
1588 
1589 static inline void raw_spin_rq_unlock_irq(struct rq *rq)
1590 {
1591 	raw_spin_rq_unlock(rq);
1592 	local_irq_enable();
1593 }
1594 
1595 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq)
1596 {
1597 	unsigned long flags;
1598 
1599 	local_irq_save(flags);
1600 	raw_spin_rq_lock(rq);
1601 
1602 	return flags;
1603 }
1604 
1605 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags)
1606 {
1607 	raw_spin_rq_unlock(rq);
1608 	local_irq_restore(flags);
1609 }
1610 
1611 #define raw_spin_rq_lock_irqsave(rq, flags)	\
1612 do {						\
1613 	flags = _raw_spin_rq_lock_irqsave(rq);	\
1614 } while (0)
1615 
1616 #ifdef CONFIG_SCHED_SMT
1617 extern void __update_idle_core(struct rq *rq);
1618 
1619 static inline void update_idle_core(struct rq *rq)
1620 {
1621 	if (static_branch_unlikely(&sched_smt_present))
1622 		__update_idle_core(rq);
1623 }
1624 
1625 #else /* !CONFIG_SCHED_SMT: */
1626 static inline void update_idle_core(struct rq *rq) { }
1627 #endif /* !CONFIG_SCHED_SMT */
1628 
1629 #ifdef CONFIG_FAIR_GROUP_SCHED
1630 
1631 static inline struct task_struct *task_of(struct sched_entity *se)
1632 {
1633 	WARN_ON_ONCE(!entity_is_task(se));
1634 	return container_of(se, struct task_struct, se);
1635 }
1636 
1637 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1638 {
1639 	return p->se.cfs_rq;
1640 }
1641 
1642 /* runqueue on which this entity is (to be) queued */
1643 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1644 {
1645 	return se->cfs_rq;
1646 }
1647 
1648 /* runqueue "owned" by this group */
1649 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1650 {
1651 	return grp->my_q;
1652 }
1653 
1654 #else /* !CONFIG_FAIR_GROUP_SCHED: */
1655 
1656 #define task_of(_se)		container_of(_se, struct task_struct, se)
1657 
1658 static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p)
1659 {
1660 	return &task_rq(p)->cfs;
1661 }
1662 
1663 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1664 {
1665 	const struct task_struct *p = task_of(se);
1666 	struct rq *rq = task_rq(p);
1667 
1668 	return &rq->cfs;
1669 }
1670 
1671 /* runqueue "owned" by this group */
1672 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1673 {
1674 	return NULL;
1675 }
1676 
1677 #endif /* !CONFIG_FAIR_GROUP_SCHED */
1678 
1679 extern void update_rq_clock(struct rq *rq);
1680 
1681 /*
1682  * rq::clock_update_flags bits
1683  *
1684  * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1685  *  call to __schedule(). This is an optimisation to avoid
1686  *  neighbouring rq clock updates.
1687  *
1688  * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1689  *  in effect and calls to update_rq_clock() are being ignored.
1690  *
1691  * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1692  *  made to update_rq_clock() since the last time rq::lock was pinned.
1693  *
1694  * If inside of __schedule(), clock_update_flags will have been
1695  * shifted left (a left shift is a cheap operation for the fast path
1696  * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1697  *
1698  *	if (rq-clock_update_flags >= RQCF_UPDATED)
1699  *
1700  * to check if %RQCF_UPDATED is set. It'll never be shifted more than
1701  * one position though, because the next rq_unpin_lock() will shift it
1702  * back.
1703  */
1704 #define RQCF_REQ_SKIP		0x01
1705 #define RQCF_ACT_SKIP		0x02
1706 #define RQCF_UPDATED		0x04
1707 
1708 static inline void assert_clock_updated(struct rq *rq)
1709 {
1710 	/*
1711 	 * The only reason for not seeing a clock update since the
1712 	 * last rq_pin_lock() is if we're currently skipping updates.
1713 	 */
1714 	WARN_ON_ONCE(rq->clock_update_flags < RQCF_ACT_SKIP);
1715 }
1716 
1717 static inline u64 rq_clock(struct rq *rq)
1718 {
1719 	lockdep_assert_rq_held(rq);
1720 	assert_clock_updated(rq);
1721 
1722 	return rq->clock;
1723 }
1724 
1725 static inline u64 rq_clock_task(struct rq *rq)
1726 {
1727 	lockdep_assert_rq_held(rq);
1728 	assert_clock_updated(rq);
1729 
1730 	return rq->clock_task;
1731 }
1732 
1733 static inline void rq_clock_skip_update(struct rq *rq)
1734 {
1735 	lockdep_assert_rq_held(rq);
1736 	rq->clock_update_flags |= RQCF_REQ_SKIP;
1737 }
1738 
1739 /*
1740  * See rt task throttling, which is the only time a skip
1741  * request is canceled.
1742  */
1743 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1744 {
1745 	lockdep_assert_rq_held(rq);
1746 	rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1747 }
1748 
1749 /*
1750  * During cpu offlining and rq wide unthrottling, we can trigger
1751  * an update_rq_clock() for several cfs and rt runqueues (Typically
1752  * when using list_for_each_entry_*)
1753  * rq_clock_start_loop_update() can be called after updating the clock
1754  * once and before iterating over the list to prevent multiple update.
1755  * After the iterative traversal, we need to call rq_clock_stop_loop_update()
1756  * to clear RQCF_ACT_SKIP of rq->clock_update_flags.
1757  */
1758 static inline void rq_clock_start_loop_update(struct rq *rq)
1759 {
1760 	lockdep_assert_rq_held(rq);
1761 	WARN_ON_ONCE(rq->clock_update_flags & RQCF_ACT_SKIP);
1762 	rq->clock_update_flags |= RQCF_ACT_SKIP;
1763 }
1764 
1765 static inline void rq_clock_stop_loop_update(struct rq *rq)
1766 {
1767 	lockdep_assert_rq_held(rq);
1768 	rq->clock_update_flags &= ~RQCF_ACT_SKIP;
1769 }
1770 
1771 struct rq_flags {
1772 	unsigned long flags;
1773 	struct pin_cookie cookie;
1774 	/*
1775 	 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1776 	 * current pin context is stashed here in case it needs to be
1777 	 * restored in rq_repin_lock().
1778 	 */
1779 	unsigned int clock_update_flags;
1780 };
1781 
1782 extern struct balance_callback balance_push_callback;
1783 
1784 #ifdef CONFIG_SCHED_CLASS_EXT
1785 extern const struct sched_class ext_sched_class;
1786 
1787 DECLARE_STATIC_KEY_FALSE(__scx_enabled);	/* SCX BPF scheduler loaded */
1788 DECLARE_STATIC_KEY_FALSE(__scx_switched_all);	/* all fair class tasks on SCX */
1789 
1790 #define scx_enabled()		static_branch_unlikely(&__scx_enabled)
1791 #define scx_switched_all()	static_branch_unlikely(&__scx_switched_all)
1792 
1793 static inline void scx_rq_clock_update(struct rq *rq, u64 clock)
1794 {
1795 	if (!scx_enabled())
1796 		return;
1797 	WRITE_ONCE(rq->scx.clock, clock);
1798 	smp_store_release(&rq->scx.flags, rq->scx.flags | SCX_RQ_CLK_VALID);
1799 }
1800 
1801 static inline void scx_rq_clock_invalidate(struct rq *rq)
1802 {
1803 	if (!scx_enabled())
1804 		return;
1805 	WRITE_ONCE(rq->scx.flags, rq->scx.flags & ~SCX_RQ_CLK_VALID);
1806 }
1807 
1808 #else /* !CONFIG_SCHED_CLASS_EXT: */
1809 #define scx_enabled()		false
1810 #define scx_switched_all()	false
1811 
1812 static inline void scx_rq_clock_update(struct rq *rq, u64 clock) {}
1813 static inline void scx_rq_clock_invalidate(struct rq *rq) {}
1814 #endif /* !CONFIG_SCHED_CLASS_EXT */
1815 
1816 /*
1817  * Lockdep annotation that avoids accidental unlocks; it's like a
1818  * sticky/continuous lockdep_assert_held().
1819  *
1820  * This avoids code that has access to 'struct rq *rq' (basically everything in
1821  * the scheduler) from accidentally unlocking the rq if they do not also have a
1822  * copy of the (on-stack) 'struct rq_flags rf'.
1823  *
1824  * Also see Documentation/locking/lockdep-design.rst.
1825  */
1826 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1827 {
1828 	rf->cookie = lockdep_pin_lock(__rq_lockp(rq));
1829 
1830 	rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1831 	rf->clock_update_flags = 0;
1832 	WARN_ON_ONCE(rq->balance_callback && rq->balance_callback != &balance_push_callback);
1833 }
1834 
1835 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1836 {
1837 	if (rq->clock_update_flags > RQCF_ACT_SKIP)
1838 		rf->clock_update_flags = RQCF_UPDATED;
1839 
1840 	scx_rq_clock_invalidate(rq);
1841 	lockdep_unpin_lock(__rq_lockp(rq), rf->cookie);
1842 }
1843 
1844 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1845 {
1846 	lockdep_repin_lock(__rq_lockp(rq), rf->cookie);
1847 
1848 	/*
1849 	 * Restore the value we stashed in @rf for this pin context.
1850 	 */
1851 	rq->clock_update_flags |= rf->clock_update_flags;
1852 }
1853 
1854 extern
1855 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1856 	__acquires(rq->lock);
1857 
1858 extern
1859 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1860 	__acquires(p->pi_lock)
1861 	__acquires(rq->lock);
1862 
1863 static inline void
1864 __task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1865 	__releases(rq->lock)
1866 {
1867 	rq_unpin_lock(rq, rf);
1868 	raw_spin_rq_unlock(rq);
1869 }
1870 
1871 static inline void
1872 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1873 	__releases(rq->lock)
1874 	__releases(p->pi_lock)
1875 {
1876 	__task_rq_unlock(rq, p, rf);
1877 	raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1878 }
1879 
1880 DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct,
1881 		    _T->rq = task_rq_lock(_T->lock, &_T->rf),
1882 		    task_rq_unlock(_T->rq, _T->lock, &_T->rf),
1883 		    struct rq *rq; struct rq_flags rf)
1884 
1885 DEFINE_LOCK_GUARD_1(__task_rq_lock, struct task_struct,
1886 		    _T->rq = __task_rq_lock(_T->lock, &_T->rf),
1887 		    __task_rq_unlock(_T->rq, _T->lock, &_T->rf),
1888 		    struct rq *rq; struct rq_flags rf)
1889 
1890 static inline void rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1891 	__acquires(rq->lock)
1892 {
1893 	raw_spin_rq_lock_irqsave(rq, rf->flags);
1894 	rq_pin_lock(rq, rf);
1895 }
1896 
1897 static inline void rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1898 	__acquires(rq->lock)
1899 {
1900 	raw_spin_rq_lock_irq(rq);
1901 	rq_pin_lock(rq, rf);
1902 }
1903 
1904 static inline void rq_lock(struct rq *rq, struct rq_flags *rf)
1905 	__acquires(rq->lock)
1906 {
1907 	raw_spin_rq_lock(rq);
1908 	rq_pin_lock(rq, rf);
1909 }
1910 
1911 static inline void rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1912 	__releases(rq->lock)
1913 {
1914 	rq_unpin_lock(rq, rf);
1915 	raw_spin_rq_unlock_irqrestore(rq, rf->flags);
1916 }
1917 
1918 static inline void rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1919 	__releases(rq->lock)
1920 {
1921 	rq_unpin_lock(rq, rf);
1922 	raw_spin_rq_unlock_irq(rq);
1923 }
1924 
1925 static inline void rq_unlock(struct rq *rq, struct rq_flags *rf)
1926 	__releases(rq->lock)
1927 {
1928 	rq_unpin_lock(rq, rf);
1929 	raw_spin_rq_unlock(rq);
1930 }
1931 
1932 DEFINE_LOCK_GUARD_1(rq_lock, struct rq,
1933 		    rq_lock(_T->lock, &_T->rf),
1934 		    rq_unlock(_T->lock, &_T->rf),
1935 		    struct rq_flags rf)
1936 
1937 DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq,
1938 		    rq_lock_irq(_T->lock, &_T->rf),
1939 		    rq_unlock_irq(_T->lock, &_T->rf),
1940 		    struct rq_flags rf)
1941 
1942 DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq,
1943 		    rq_lock_irqsave(_T->lock, &_T->rf),
1944 		    rq_unlock_irqrestore(_T->lock, &_T->rf),
1945 		    struct rq_flags rf)
1946 
1947 static inline struct rq *this_rq_lock_irq(struct rq_flags *rf)
1948 	__acquires(rq->lock)
1949 {
1950 	struct rq *rq;
1951 
1952 	local_irq_disable();
1953 	rq = this_rq();
1954 	rq_lock(rq, rf);
1955 
1956 	return rq;
1957 }
1958 
1959 #ifdef CONFIG_NUMA
1960 
1961 enum numa_topology_type {
1962 	NUMA_DIRECT,
1963 	NUMA_GLUELESS_MESH,
1964 	NUMA_BACKPLANE,
1965 };
1966 
1967 extern enum numa_topology_type sched_numa_topology_type;
1968 extern int sched_max_numa_distance;
1969 extern bool find_numa_distance(int distance);
1970 extern void sched_init_numa(int offline_node);
1971 extern void sched_update_numa(int cpu, bool online);
1972 extern void sched_domains_numa_masks_set(unsigned int cpu);
1973 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1974 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1975 
1976 #else /* !CONFIG_NUMA: */
1977 
1978 static inline void sched_init_numa(int offline_node) { }
1979 static inline void sched_update_numa(int cpu, bool online) { }
1980 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
1981 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1982 
1983 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1984 {
1985 	return nr_cpu_ids;
1986 }
1987 
1988 #endif /* !CONFIG_NUMA */
1989 
1990 #ifdef CONFIG_NUMA_BALANCING
1991 
1992 /* The regions in numa_faults array from task_struct */
1993 enum numa_faults_stats {
1994 	NUMA_MEM = 0,
1995 	NUMA_CPU,
1996 	NUMA_MEMBUF,
1997 	NUMA_CPUBUF
1998 };
1999 
2000 extern void sched_setnuma(struct task_struct *p, int node);
2001 extern int migrate_task_to(struct task_struct *p, int cpu);
2002 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
2003 			int cpu, int scpu);
2004 extern void init_numa_balancing(u64 clone_flags, struct task_struct *p);
2005 
2006 #else /* !CONFIG_NUMA_BALANCING: */
2007 
2008 static inline void
2009 init_numa_balancing(u64 clone_flags, struct task_struct *p)
2010 {
2011 }
2012 
2013 #endif /* !CONFIG_NUMA_BALANCING */
2014 
2015 static inline void
2016 queue_balance_callback(struct rq *rq,
2017 		       struct balance_callback *head,
2018 		       void (*func)(struct rq *rq))
2019 {
2020 	lockdep_assert_rq_held(rq);
2021 
2022 	/*
2023 	 * Don't (re)queue an already queued item; nor queue anything when
2024 	 * balance_push() is active, see the comment with
2025 	 * balance_push_callback.
2026 	 */
2027 	if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
2028 		return;
2029 
2030 	head->func = func;
2031 	head->next = rq->balance_callback;
2032 	rq->balance_callback = head;
2033 }
2034 
2035 #define rcu_dereference_check_sched_domain(p) \
2036 	rcu_dereference_check((p), lockdep_is_held(&sched_domains_mutex))
2037 
2038 /*
2039  * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
2040  * See destroy_sched_domains: call_rcu for details.
2041  *
2042  * The domain tree of any CPU may only be accessed from within
2043  * preempt-disabled sections.
2044  */
2045 #define for_each_domain(cpu, __sd) \
2046 	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
2047 			__sd; __sd = __sd->parent)
2048 
2049 /* A mask of all the SD flags that have the SDF_SHARED_CHILD metaflag */
2050 #define SD_FLAG(name, mflags) (name * !!((mflags) & SDF_SHARED_CHILD)) |
2051 static const unsigned int SD_SHARED_CHILD_MASK =
2052 #include <linux/sched/sd_flags.h>
2053 0;
2054 #undef SD_FLAG
2055 
2056 /**
2057  * highest_flag_domain - Return highest sched_domain containing flag.
2058  * @cpu:	The CPU whose highest level of sched domain is to
2059  *		be returned.
2060  * @flag:	The flag to check for the highest sched_domain
2061  *		for the given CPU.
2062  *
2063  * Returns the highest sched_domain of a CPU which contains @flag. If @flag has
2064  * the SDF_SHARED_CHILD metaflag, all the children domains also have @flag.
2065  */
2066 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
2067 {
2068 	struct sched_domain *sd, *hsd = NULL;
2069 
2070 	for_each_domain(cpu, sd) {
2071 		if (sd->flags & flag) {
2072 			hsd = sd;
2073 			continue;
2074 		}
2075 
2076 		/*
2077 		 * Stop the search if @flag is known to be shared at lower
2078 		 * levels. It will not be found further up.
2079 		 */
2080 		if (flag & SD_SHARED_CHILD_MASK)
2081 			break;
2082 	}
2083 
2084 	return hsd;
2085 }
2086 
2087 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
2088 {
2089 	struct sched_domain *sd;
2090 
2091 	for_each_domain(cpu, sd) {
2092 		if (sd->flags & flag)
2093 			break;
2094 	}
2095 
2096 	return sd;
2097 }
2098 
2099 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
2100 DECLARE_PER_CPU(int, sd_llc_size);
2101 DECLARE_PER_CPU(int, sd_llc_id);
2102 DECLARE_PER_CPU(int, sd_share_id);
2103 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
2104 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
2105 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
2106 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
2107 
2108 extern struct static_key_false sched_asym_cpucapacity;
2109 extern struct static_key_false sched_cluster_active;
2110 
2111 static __always_inline bool sched_asym_cpucap_active(void)
2112 {
2113 	return static_branch_unlikely(&sched_asym_cpucapacity);
2114 }
2115 
2116 struct sched_group_capacity {
2117 	atomic_t		ref;
2118 	/*
2119 	 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
2120 	 * for a single CPU.
2121 	 */
2122 	unsigned long		capacity;
2123 	unsigned long		min_capacity;		/* Min per-CPU capacity in group */
2124 	unsigned long		max_capacity;		/* Max per-CPU capacity in group */
2125 	unsigned long		next_update;
2126 	int			imbalance;		/* XXX unrelated to capacity but shared group state */
2127 
2128 	int			id;
2129 
2130 	unsigned long		cpumask[];		/* Balance mask */
2131 };
2132 
2133 struct sched_group {
2134 	struct sched_group	*next;			/* Must be a circular list */
2135 	atomic_t		ref;
2136 
2137 	unsigned int		group_weight;
2138 	unsigned int		cores;
2139 	struct sched_group_capacity *sgc;
2140 	int			asym_prefer_cpu;	/* CPU of highest priority in group */
2141 	int			flags;
2142 
2143 	/*
2144 	 * The CPUs this group covers.
2145 	 *
2146 	 * NOTE: this field is variable length. (Allocated dynamically
2147 	 * by attaching extra space to the end of the structure,
2148 	 * depending on how many CPUs the kernel has booted up with)
2149 	 */
2150 	unsigned long		cpumask[];
2151 };
2152 
2153 static inline struct cpumask *sched_group_span(struct sched_group *sg)
2154 {
2155 	return to_cpumask(sg->cpumask);
2156 }
2157 
2158 /*
2159  * See build_balance_mask().
2160  */
2161 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
2162 {
2163 	return to_cpumask(sg->sgc->cpumask);
2164 }
2165 
2166 extern int group_balance_cpu(struct sched_group *sg);
2167 
2168 extern void update_sched_domain_debugfs(void);
2169 extern void dirty_sched_domain_sysctl(int cpu);
2170 
2171 extern int sched_update_scaling(void);
2172 
2173 static inline const struct cpumask *task_user_cpus(struct task_struct *p)
2174 {
2175 	if (!p->user_cpus_ptr)
2176 		return cpu_possible_mask; /* &init_task.cpus_mask */
2177 	return p->user_cpus_ptr;
2178 }
2179 
2180 #ifdef CONFIG_CGROUP_SCHED
2181 
2182 /*
2183  * Return the group to which this tasks belongs.
2184  *
2185  * We cannot use task_css() and friends because the cgroup subsystem
2186  * changes that value before the cgroup_subsys::attach() method is called,
2187  * therefore we cannot pin it and might observe the wrong value.
2188  *
2189  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
2190  * core changes this before calling sched_move_task().
2191  *
2192  * Instead we use a 'copy' which is updated from sched_move_task() while
2193  * holding both task_struct::pi_lock and rq::lock.
2194  */
2195 static inline struct task_group *task_group(struct task_struct *p)
2196 {
2197 	return p->sched_task_group;
2198 }
2199 
2200 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
2201 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
2202 {
2203 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
2204 	struct task_group *tg = task_group(p);
2205 #endif
2206 
2207 #ifdef CONFIG_FAIR_GROUP_SCHED
2208 	set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
2209 	p->se.cfs_rq = tg->cfs_rq[cpu];
2210 	p->se.parent = tg->se[cpu];
2211 	p->se.depth = tg->se[cpu] ? tg->se[cpu]->depth + 1 : 0;
2212 #endif
2213 
2214 #ifdef CONFIG_RT_GROUP_SCHED
2215 	/*
2216 	 * p->rt.rt_rq is NULL initially and it is easier to assign
2217 	 * root_task_group's rt_rq than switching in rt_rq_of_se()
2218 	 * Clobbers tg(!)
2219 	 */
2220 	if (!rt_group_sched_enabled())
2221 		tg = &root_task_group;
2222 	p->rt.rt_rq  = tg->rt_rq[cpu];
2223 	p->rt.parent = tg->rt_se[cpu];
2224 #endif /* CONFIG_RT_GROUP_SCHED */
2225 }
2226 
2227 #else /* !CONFIG_CGROUP_SCHED: */
2228 
2229 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
2230 
2231 static inline struct task_group *task_group(struct task_struct *p)
2232 {
2233 	return NULL;
2234 }
2235 
2236 #endif /* !CONFIG_CGROUP_SCHED */
2237 
2238 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
2239 {
2240 	set_task_rq(p, cpu);
2241 #ifdef CONFIG_SMP
2242 	/*
2243 	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
2244 	 * successfully executed on another CPU. We must ensure that updates of
2245 	 * per-task data have been completed by this moment.
2246 	 */
2247 	smp_wmb();
2248 	WRITE_ONCE(task_thread_info(p)->cpu, cpu);
2249 	p->wake_cpu = cpu;
2250 	rseq_sched_set_ids_changed(p);
2251 #endif /* CONFIG_SMP */
2252 }
2253 
2254 /*
2255  * Tunables:
2256  */
2257 
2258 #define SCHED_FEAT(name, enabled)	\
2259 	__SCHED_FEAT_##name ,
2260 
2261 enum {
2262 #include "features.h"
2263 	__SCHED_FEAT_NR,
2264 };
2265 
2266 #undef SCHED_FEAT
2267 
2268 /*
2269  * To support run-time toggling of sched features, all the translation units
2270  * (but core.c) reference the sysctl_sched_features defined in core.c.
2271  */
2272 extern __read_mostly unsigned int sysctl_sched_features;
2273 
2274 #ifdef CONFIG_JUMP_LABEL
2275 
2276 #define SCHED_FEAT(name, enabled)					\
2277 static __always_inline bool static_branch_##name(struct static_key *key) \
2278 {									\
2279 	return static_key_##enabled(key);				\
2280 }
2281 
2282 #include "features.h"
2283 #undef SCHED_FEAT
2284 
2285 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
2286 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
2287 
2288 #else /* !CONFIG_JUMP_LABEL: */
2289 
2290 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2291 
2292 #endif /* !CONFIG_JUMP_LABEL */
2293 
2294 extern struct static_key_false sched_numa_balancing;
2295 extern struct static_key_false sched_schedstats;
2296 
2297 static inline u64 global_rt_period(void)
2298 {
2299 	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
2300 }
2301 
2302 static inline u64 global_rt_runtime(void)
2303 {
2304 	if (sysctl_sched_rt_runtime < 0)
2305 		return RUNTIME_INF;
2306 
2307 	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
2308 }
2309 
2310 /*
2311  * Is p the current execution context?
2312  */
2313 static inline int task_current(struct rq *rq, struct task_struct *p)
2314 {
2315 	return rq->curr == p;
2316 }
2317 
2318 /*
2319  * Is p the current scheduling context?
2320  *
2321  * Note that it might be the current execution context at the same time if
2322  * rq->curr == rq->donor == p.
2323  */
2324 static inline int task_current_donor(struct rq *rq, struct task_struct *p)
2325 {
2326 	return rq->donor == p;
2327 }
2328 
2329 static inline bool task_is_blocked(struct task_struct *p)
2330 {
2331 	if (!sched_proxy_exec())
2332 		return false;
2333 
2334 	return !!p->blocked_on;
2335 }
2336 
2337 static inline int task_on_cpu(struct rq *rq, struct task_struct *p)
2338 {
2339 	return p->on_cpu;
2340 }
2341 
2342 static inline int task_on_rq_queued(struct task_struct *p)
2343 {
2344 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_QUEUED;
2345 }
2346 
2347 static inline int task_on_rq_migrating(struct task_struct *p)
2348 {
2349 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
2350 }
2351 
2352 /* Wake flags. The first three directly map to some SD flag value */
2353 #define WF_EXEC			0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
2354 #define WF_FORK			0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
2355 #define WF_TTWU			0x08 /* Wakeup;            maps to SD_BALANCE_WAKE */
2356 
2357 #define WF_SYNC			0x10 /* Waker goes to sleep after wakeup */
2358 #define WF_MIGRATED		0x20 /* Internal use, task got migrated */
2359 #define WF_CURRENT_CPU		0x40 /* Prefer to move the wakee to the current CPU. */
2360 #define WF_RQ_SELECTED		0x80 /* ->select_task_rq() was called */
2361 
2362 static_assert(WF_EXEC == SD_BALANCE_EXEC);
2363 static_assert(WF_FORK == SD_BALANCE_FORK);
2364 static_assert(WF_TTWU == SD_BALANCE_WAKE);
2365 
2366 /*
2367  * To aid in avoiding the subversion of "niceness" due to uneven distribution
2368  * of tasks with abnormal "nice" values across CPUs the contribution that
2369  * each task makes to its run queue's load is weighted according to its
2370  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
2371  * scaled version of the new time slice allocation that they receive on time
2372  * slice expiry etc.
2373  */
2374 
2375 #define WEIGHT_IDLEPRIO		3
2376 #define WMULT_IDLEPRIO		1431655765
2377 
2378 extern const int		sched_prio_to_weight[40];
2379 extern const u32		sched_prio_to_wmult[40];
2380 
2381 /*
2382  * {de,en}queue flags:
2383  *
2384  * SLEEP/WAKEUP - task is no-longer/just-became runnable
2385  *
2386  * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
2387  *                are in a known state which allows modification. Such pairs
2388  *                should preserve as much state as possible.
2389  *
2390  * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
2391  *        in the runqueue. IOW the priority is allowed to change. Callers
2392  *        must expect to deal with balance callbacks.
2393  *
2394  * NOCLOCK - skip the update_rq_clock() (avoids double updates)
2395  *
2396  * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE)
2397  *
2398  * DELAYED - de/re-queue a sched_delayed task
2399  *
2400  * CLASS - going to update p->sched_class; makes sched_change call the
2401  *         various switch methods.
2402  *
2403  * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
2404  * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
2405  * ENQUEUE_MIGRATED  - the task was migrated during wakeup
2406  * ENQUEUE_RQ_SELECTED - ->select_task_rq() was called
2407  *
2408  * XXX SAVE/RESTORE in combination with CLASS doesn't really make sense, but
2409  * SCHED_DEADLINE seems to rely on this for now.
2410  */
2411 
2412 #define DEQUEUE_SLEEP		0x0001 /* Matches ENQUEUE_WAKEUP */
2413 #define DEQUEUE_SAVE		0x0002 /* Matches ENQUEUE_RESTORE */
2414 #define DEQUEUE_MOVE		0x0004 /* Matches ENQUEUE_MOVE */
2415 #define DEQUEUE_NOCLOCK		0x0008 /* Matches ENQUEUE_NOCLOCK */
2416 
2417 #define DEQUEUE_MIGRATING	0x0010 /* Matches ENQUEUE_MIGRATING */
2418 #define DEQUEUE_DELAYED		0x0020 /* Matches ENQUEUE_DELAYED */
2419 #define DEQUEUE_CLASS		0x0040 /* Matches ENQUEUE_CLASS */
2420 
2421 #define DEQUEUE_SPECIAL		0x00010000
2422 #define DEQUEUE_THROTTLE	0x00020000
2423 
2424 #define ENQUEUE_WAKEUP		0x0001
2425 #define ENQUEUE_RESTORE		0x0002
2426 #define ENQUEUE_MOVE		0x0004
2427 #define ENQUEUE_NOCLOCK		0x0008
2428 
2429 #define ENQUEUE_MIGRATING	0x0010
2430 #define ENQUEUE_DELAYED		0x0020
2431 #define ENQUEUE_CLASS		0x0040
2432 
2433 #define ENQUEUE_HEAD		0x00010000
2434 #define ENQUEUE_REPLENISH	0x00020000
2435 #define ENQUEUE_MIGRATED	0x00040000
2436 #define ENQUEUE_INITIAL		0x00080000
2437 #define ENQUEUE_RQ_SELECTED	0x00100000
2438 
2439 #define RETRY_TASK		((void *)-1UL)
2440 
2441 struct affinity_context {
2442 	const struct cpumask	*new_mask;
2443 	struct cpumask		*user_mask;
2444 	unsigned int		flags;
2445 };
2446 
2447 extern s64 update_curr_common(struct rq *rq);
2448 
2449 struct sched_class {
2450 
2451 #ifdef CONFIG_UCLAMP_TASK
2452 	int uclamp_enabled;
2453 #endif
2454 	/*
2455 	 * idle:  0
2456 	 * ext:   1
2457 	 * fair:  2
2458 	 * rt:    4
2459 	 * dl:    8
2460 	 * stop: 16
2461 	 */
2462 	unsigned int queue_mask;
2463 
2464 	/*
2465 	 * move_queued_task/activate_task/enqueue_task: rq->lock
2466 	 * ttwu_do_activate/activate_task/enqueue_task: rq->lock
2467 	 * wake_up_new_task/activate_task/enqueue_task: task_rq_lock
2468 	 * ttwu_runnable/enqueue_task: task_rq_lock
2469 	 * proxy_task_current: rq->lock
2470 	 * sched_change_end
2471 	 */
2472 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
2473 	/*
2474 	 * move_queued_task/deactivate_task/dequeue_task: rq->lock
2475 	 * __schedule/block_task/dequeue_task: rq->lock
2476 	 * proxy_task_current: rq->lock
2477 	 * wait_task_inactive: task_rq_lock
2478 	 * sched_change_begin
2479 	 */
2480 	bool (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
2481 
2482 	/*
2483 	 * do_sched_yield: rq->lock
2484 	 */
2485 	void (*yield_task)   (struct rq *rq);
2486 	/*
2487 	 * yield_to: rq->lock (double)
2488 	 */
2489 	bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
2490 
2491 	/*
2492 	 * move_queued_task: rq->lock
2493 	 * __migrate_swap_task: rq->lock
2494 	 * ttwu_do_activate: rq->lock
2495 	 * ttwu_runnable: task_rq_lock
2496 	 * wake_up_new_task: task_rq_lock
2497 	 */
2498 	void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags);
2499 
2500 	/*
2501 	 * schedule/pick_next_task/prev_balance: rq->lock
2502 	 */
2503 	int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2504 
2505 	/*
2506 	 * schedule/pick_next_task: rq->lock
2507 	 */
2508 	struct task_struct *(*pick_task)(struct rq *rq, struct rq_flags *rf);
2509 	/*
2510 	 * Optional! When implemented pick_next_task() should be equivalent to:
2511 	 *
2512 	 *   next = pick_task();
2513 	 *   if (next) {
2514 	 *       put_prev_task(prev);
2515 	 *       set_next_task_first(next);
2516 	 *   }
2517 	 */
2518 	struct task_struct *(*pick_next_task)(struct rq *rq, struct task_struct *prev,
2519 					      struct rq_flags *rf);
2520 
2521 	/*
2522 	 * sched_change:
2523 	 * __schedule: rq->lock
2524 	 */
2525 	void (*put_prev_task)(struct rq *rq, struct task_struct *p, struct task_struct *next);
2526 	void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
2527 
2528 	/*
2529 	 * select_task_rq: p->pi_lock
2530 	 * sched_exec: p->pi_lock
2531 	 */
2532 	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
2533 
2534 	/*
2535 	 * set_task_cpu: p->pi_lock || rq->lock (ttwu like)
2536 	 */
2537 	void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
2538 
2539 	/*
2540 	 * ttwu_do_activate: rq->lock
2541 	 * wake_up_new_task: task_rq_lock
2542 	 */
2543 	void (*task_woken)(struct rq *this_rq, struct task_struct *task);
2544 
2545 	/*
2546 	 * do_set_cpus_allowed: task_rq_lock + sched_change
2547 	 */
2548 	void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx);
2549 
2550 	/*
2551 	 * sched_set_rq_{on,off}line: rq->lock
2552 	 */
2553 	void (*rq_online)(struct rq *rq);
2554 	void (*rq_offline)(struct rq *rq);
2555 
2556 	/*
2557 	 * push_cpu_stop: p->pi_lock && rq->lock
2558 	 */
2559 	struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
2560 
2561 	/*
2562 	 * hrtick: rq->lock
2563 	 * sched_tick: rq->lock
2564 	 * sched_tick_remote: rq->lock
2565 	 */
2566 	void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
2567 	/*
2568 	 * sched_cgroup_fork: p->pi_lock
2569 	 */
2570 	void (*task_fork)(struct task_struct *p);
2571 	/*
2572 	 * finish_task_switch: no locks
2573 	 */
2574 	void (*task_dead)(struct task_struct *p);
2575 
2576 	/*
2577 	 * sched_change
2578 	 */
2579 	void (*switching_from)(struct rq *this_rq, struct task_struct *task);
2580 	void (*switched_from) (struct rq *this_rq, struct task_struct *task);
2581 	void (*switching_to)  (struct rq *this_rq, struct task_struct *task);
2582 	void (*switched_to)   (struct rq *this_rq, struct task_struct *task);
2583 	u64  (*get_prio)     (struct rq *this_rq, struct task_struct *task);
2584 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
2585 			      u64 oldprio);
2586 
2587 	/*
2588 	 * set_load_weight: task_rq_lock + sched_change
2589 	 * __setscheduler_parms: task_rq_lock + sched_change
2590 	 */
2591 	void (*reweight_task)(struct rq *this_rq, struct task_struct *task,
2592 			      const struct load_weight *lw);
2593 
2594 	/*
2595 	 * sched_rr_get_interval: task_rq_lock
2596 	 */
2597 	unsigned int (*get_rr_interval)(struct rq *rq,
2598 					struct task_struct *task);
2599 
2600 	/*
2601 	 * task_sched_runtime: task_rq_lock
2602 	 */
2603 	void (*update_curr)(struct rq *rq);
2604 
2605 #ifdef CONFIG_FAIR_GROUP_SCHED
2606 	/*
2607 	 * sched_change_group: task_rq_lock + sched_change
2608 	 */
2609 	void (*task_change_group)(struct task_struct *p);
2610 #endif
2611 
2612 #ifdef CONFIG_SCHED_CORE
2613 	/*
2614 	 * pick_next_task: rq->lock
2615 	 * try_steal_cookie: rq->lock (double)
2616 	 */
2617 	int (*task_is_throttled)(struct task_struct *p, int cpu);
2618 #endif
2619 };
2620 
2621 /*
2622  * Does not nest; only used around sched_class::pick_task() rq-lock-breaks.
2623  */
2624 static inline void rq_modified_clear(struct rq *rq)
2625 {
2626 	rq->queue_mask = 0;
2627 }
2628 
2629 static inline bool rq_modified_above(struct rq *rq, const struct sched_class * class)
2630 {
2631 	unsigned int mask = class->queue_mask;
2632 	return rq->queue_mask & ~((mask << 1) - 1);
2633 }
2634 
2635 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
2636 {
2637 	WARN_ON_ONCE(rq->donor != prev);
2638 	prev->sched_class->put_prev_task(rq, prev, NULL);
2639 }
2640 
2641 static inline void set_next_task(struct rq *rq, struct task_struct *next)
2642 {
2643 	next->sched_class->set_next_task(rq, next, false);
2644 }
2645 
2646 static inline void
2647 __put_prev_set_next_dl_server(struct rq *rq,
2648 			      struct task_struct *prev,
2649 			      struct task_struct *next)
2650 {
2651 	prev->dl_server = NULL;
2652 	next->dl_server = rq->dl_server;
2653 	rq->dl_server = NULL;
2654 }
2655 
2656 static inline void put_prev_set_next_task(struct rq *rq,
2657 					  struct task_struct *prev,
2658 					  struct task_struct *next)
2659 {
2660 	WARN_ON_ONCE(rq->donor != prev);
2661 
2662 	__put_prev_set_next_dl_server(rq, prev, next);
2663 
2664 	if (next == prev)
2665 		return;
2666 
2667 	prev->sched_class->put_prev_task(rq, prev, next);
2668 	next->sched_class->set_next_task(rq, next, true);
2669 }
2670 
2671 /*
2672  * Helper to define a sched_class instance; each one is placed in a separate
2673  * section which is ordered by the linker script:
2674  *
2675  *   include/asm-generic/vmlinux.lds.h
2676  *
2677  * *CAREFUL* they are laid out in *REVERSE* order!!!
2678  *
2679  * Also enforce alignment on the instance, not the type, to guarantee layout.
2680  */
2681 #define DEFINE_SCHED_CLASS(name) \
2682 const struct sched_class name##_sched_class \
2683 	__aligned(__alignof__(struct sched_class)) \
2684 	__section("__" #name "_sched_class")
2685 
2686 /* Defined in include/asm-generic/vmlinux.lds.h */
2687 extern struct sched_class __sched_class_highest[];
2688 extern struct sched_class __sched_class_lowest[];
2689 
2690 extern const struct sched_class stop_sched_class;
2691 extern const struct sched_class dl_sched_class;
2692 extern const struct sched_class rt_sched_class;
2693 extern const struct sched_class fair_sched_class;
2694 extern const struct sched_class idle_sched_class;
2695 
2696 /*
2697  * Iterate only active classes. SCX can take over all fair tasks or be
2698  * completely disabled. If the former, skip fair. If the latter, skip SCX.
2699  */
2700 static inline const struct sched_class *next_active_class(const struct sched_class *class)
2701 {
2702 	class++;
2703 #ifdef CONFIG_SCHED_CLASS_EXT
2704 	if (scx_switched_all() && class == &fair_sched_class)
2705 		class++;
2706 	if (!scx_enabled() && class == &ext_sched_class)
2707 		class++;
2708 #endif
2709 	return class;
2710 }
2711 
2712 #define for_class_range(class, _from, _to) \
2713 	for (class = (_from); class < (_to); class++)
2714 
2715 #define for_each_class(class) \
2716 	for_class_range(class, __sched_class_highest, __sched_class_lowest)
2717 
2718 #define for_active_class_range(class, _from, _to)				\
2719 	for (class = (_from); class != (_to); class = next_active_class(class))
2720 
2721 #define for_each_active_class(class)						\
2722 	for_active_class_range(class, __sched_class_highest, __sched_class_lowest)
2723 
2724 #define sched_class_above(_a, _b)	((_a) < (_b))
2725 
2726 static inline bool sched_stop_runnable(struct rq *rq)
2727 {
2728 	return rq->stop && task_on_rq_queued(rq->stop);
2729 }
2730 
2731 static inline bool sched_dl_runnable(struct rq *rq)
2732 {
2733 	return rq->dl.dl_nr_running > 0;
2734 }
2735 
2736 static inline bool sched_rt_runnable(struct rq *rq)
2737 {
2738 	return rq->rt.rt_queued > 0;
2739 }
2740 
2741 static inline bool sched_fair_runnable(struct rq *rq)
2742 {
2743 	return rq->cfs.nr_queued > 0;
2744 }
2745 
2746 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev,
2747 					       struct rq_flags *rf);
2748 extern struct task_struct *pick_task_idle(struct rq *rq, struct rq_flags *rf);
2749 
2750 #define SCA_CHECK		0x01
2751 #define SCA_MIGRATE_DISABLE	0x02
2752 #define SCA_MIGRATE_ENABLE	0x04
2753 #define SCA_USER		0x08
2754 
2755 extern void update_group_capacity(struct sched_domain *sd, int cpu);
2756 
2757 extern void sched_balance_trigger(struct rq *rq);
2758 
2759 extern int __set_cpus_allowed_ptr(struct task_struct *p, struct affinity_context *ctx);
2760 extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx);
2761 
2762 static inline bool task_allowed_on_cpu(struct task_struct *p, int cpu)
2763 {
2764 	/* When not in the task's cpumask, no point in looking further. */
2765 	if (!cpumask_test_cpu(cpu, p->cpus_ptr))
2766 		return false;
2767 
2768 	/* Can @cpu run a user thread? */
2769 	if (!(p->flags & PF_KTHREAD) && !task_cpu_possible(cpu, p))
2770 		return false;
2771 
2772 	return true;
2773 }
2774 
2775 static inline cpumask_t *alloc_user_cpus_ptr(int node)
2776 {
2777 	/*
2778 	 * See set_cpus_allowed_force() above for the rcu_head usage.
2779 	 */
2780 	int size = max_t(int, cpumask_size(), sizeof(struct rcu_head));
2781 
2782 	return kmalloc_node(size, GFP_KERNEL, node);
2783 }
2784 
2785 static inline struct task_struct *get_push_task(struct rq *rq)
2786 {
2787 	struct task_struct *p = rq->donor;
2788 
2789 	lockdep_assert_rq_held(rq);
2790 
2791 	if (rq->push_busy)
2792 		return NULL;
2793 
2794 	if (p->nr_cpus_allowed == 1)
2795 		return NULL;
2796 
2797 	if (p->migration_disabled)
2798 		return NULL;
2799 
2800 	rq->push_busy = true;
2801 	return get_task_struct(p);
2802 }
2803 
2804 extern int push_cpu_stop(void *arg);
2805 
2806 #ifdef CONFIG_CPU_IDLE
2807 
2808 static inline void idle_set_state(struct rq *rq,
2809 				  struct cpuidle_state *idle_state)
2810 {
2811 	rq->idle_state = idle_state;
2812 }
2813 
2814 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2815 {
2816 	WARN_ON_ONCE(!rcu_read_lock_held());
2817 
2818 	return rq->idle_state;
2819 }
2820 
2821 #else /* !CONFIG_CPU_IDLE: */
2822 
2823 static inline void idle_set_state(struct rq *rq,
2824 				  struct cpuidle_state *idle_state)
2825 {
2826 }
2827 
2828 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2829 {
2830 	return NULL;
2831 }
2832 
2833 #endif /* !CONFIG_CPU_IDLE */
2834 
2835 extern void schedule_idle(void);
2836 asmlinkage void schedule_user(void);
2837 
2838 extern void sysrq_sched_debug_show(void);
2839 extern void sched_init_granularity(void);
2840 extern void update_max_interval(void);
2841 
2842 extern void init_sched_dl_class(void);
2843 extern void init_sched_rt_class(void);
2844 extern void init_sched_fair_class(void);
2845 
2846 extern void resched_curr(struct rq *rq);
2847 extern void resched_curr_lazy(struct rq *rq);
2848 extern void resched_cpu(int cpu);
2849 
2850 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
2851 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq);
2852 
2853 extern void init_dl_entity(struct sched_dl_entity *dl_se);
2854 
2855 extern void init_cfs_throttle_work(struct task_struct *p);
2856 
2857 #define BW_SHIFT		20
2858 #define BW_UNIT			(1 << BW_SHIFT)
2859 #define RATIO_SHIFT		8
2860 #define MAX_BW_BITS		(64 - BW_SHIFT)
2861 #define MAX_BW			((1ULL << MAX_BW_BITS) - 1)
2862 
2863 extern unsigned long to_ratio(u64 period, u64 runtime);
2864 
2865 extern void init_entity_runnable_average(struct sched_entity *se);
2866 extern void post_init_entity_util_avg(struct task_struct *p);
2867 
2868 #ifdef CONFIG_NO_HZ_FULL
2869 extern bool sched_can_stop_tick(struct rq *rq);
2870 extern int __init sched_tick_offload_init(void);
2871 
2872 /*
2873  * Tick may be needed by tasks in the runqueue depending on their policy and
2874  * requirements. If tick is needed, lets send the target an IPI to kick it out of
2875  * nohz mode if necessary.
2876  */
2877 static inline void sched_update_tick_dependency(struct rq *rq)
2878 {
2879 	int cpu = cpu_of(rq);
2880 
2881 	if (!tick_nohz_full_cpu(cpu))
2882 		return;
2883 
2884 	if (sched_can_stop_tick(rq))
2885 		tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
2886 	else
2887 		tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
2888 }
2889 #else /* !CONFIG_NO_HZ_FULL: */
2890 static inline int sched_tick_offload_init(void) { return 0; }
2891 static inline void sched_update_tick_dependency(struct rq *rq) { }
2892 #endif /* !CONFIG_NO_HZ_FULL */
2893 
2894 static inline void add_nr_running(struct rq *rq, unsigned count)
2895 {
2896 	unsigned prev_nr = rq->nr_running;
2897 
2898 	rq->nr_running = prev_nr + count;
2899 	if (trace_sched_update_nr_running_tp_enabled()) {
2900 		call_trace_sched_update_nr_running(rq, count);
2901 	}
2902 
2903 	if (prev_nr < 2 && rq->nr_running >= 2)
2904 		set_rd_overloaded(rq->rd, 1);
2905 
2906 	sched_update_tick_dependency(rq);
2907 }
2908 
2909 static inline void sub_nr_running(struct rq *rq, unsigned count)
2910 {
2911 	rq->nr_running -= count;
2912 	if (trace_sched_update_nr_running_tp_enabled()) {
2913 		call_trace_sched_update_nr_running(rq, -count);
2914 	}
2915 
2916 	/* Check if we still need preemption */
2917 	sched_update_tick_dependency(rq);
2918 }
2919 
2920 static inline void __block_task(struct rq *rq, struct task_struct *p)
2921 {
2922 	if (p->sched_contributes_to_load)
2923 		rq->nr_uninterruptible++;
2924 
2925 	if (p->in_iowait) {
2926 		atomic_inc(&rq->nr_iowait);
2927 		delayacct_blkio_start();
2928 	}
2929 
2930 	ASSERT_EXCLUSIVE_WRITER(p->on_rq);
2931 
2932 	/*
2933 	 * The moment this write goes through, ttwu() can swoop in and migrate
2934 	 * this task, rendering our rq->__lock ineffective.
2935 	 *
2936 	 * __schedule()				try_to_wake_up()
2937 	 *   LOCK rq->__lock			  LOCK p->pi_lock
2938 	 *   pick_next_task()
2939 	 *     pick_next_task_fair()
2940 	 *       pick_next_entity()
2941 	 *         dequeue_entities()
2942 	 *           __block_task()
2943 	 *             RELEASE p->on_rq = 0	  if (p->on_rq && ...)
2944 	 *					    break;
2945 	 *
2946 	 *					  ACQUIRE (after ctrl-dep)
2947 	 *
2948 	 *					  cpu = select_task_rq();
2949 	 *					  set_task_cpu(p, cpu);
2950 	 *					  ttwu_queue()
2951 	 *					    ttwu_do_activate()
2952 	 *					      LOCK rq->__lock
2953 	 *					      activate_task()
2954 	 *					        STORE p->on_rq = 1
2955 	 *   UNLOCK rq->__lock
2956 	 *
2957 	 * Callers must ensure to not reference @p after this -- we no longer
2958 	 * own it.
2959 	 */
2960 	smp_store_release(&p->on_rq, 0);
2961 }
2962 
2963 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
2964 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
2965 
2966 extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags);
2967 
2968 #ifdef CONFIG_PREEMPT_RT
2969 # define SCHED_NR_MIGRATE_BREAK 8
2970 #else
2971 # define SCHED_NR_MIGRATE_BREAK 32
2972 #endif
2973 
2974 extern __read_mostly unsigned int sysctl_sched_nr_migrate;
2975 extern __read_mostly unsigned int sysctl_sched_migration_cost;
2976 
2977 extern unsigned int sysctl_sched_base_slice;
2978 
2979 extern int sysctl_resched_latency_warn_ms;
2980 extern int sysctl_resched_latency_warn_once;
2981 
2982 extern unsigned int sysctl_sched_tunable_scaling;
2983 
2984 extern unsigned int sysctl_numa_balancing_scan_delay;
2985 extern unsigned int sysctl_numa_balancing_scan_period_min;
2986 extern unsigned int sysctl_numa_balancing_scan_period_max;
2987 extern unsigned int sysctl_numa_balancing_scan_size;
2988 extern unsigned int sysctl_numa_balancing_hot_threshold;
2989 
2990 #ifdef CONFIG_SCHED_HRTICK
2991 
2992 /*
2993  * Use hrtick when:
2994  *  - enabled by features
2995  *  - hrtimer is actually high res
2996  */
2997 static inline int hrtick_enabled(struct rq *rq)
2998 {
2999 	if (!cpu_active(cpu_of(rq)))
3000 		return 0;
3001 	return hrtimer_is_hres_active(&rq->hrtick_timer);
3002 }
3003 
3004 static inline int hrtick_enabled_fair(struct rq *rq)
3005 {
3006 	if (!sched_feat(HRTICK))
3007 		return 0;
3008 	return hrtick_enabled(rq);
3009 }
3010 
3011 static inline int hrtick_enabled_dl(struct rq *rq)
3012 {
3013 	if (!sched_feat(HRTICK_DL))
3014 		return 0;
3015 	return hrtick_enabled(rq);
3016 }
3017 
3018 extern void hrtick_start(struct rq *rq, u64 delay);
3019 
3020 #else /* !CONFIG_SCHED_HRTICK: */
3021 
3022 static inline int hrtick_enabled_fair(struct rq *rq)
3023 {
3024 	return 0;
3025 }
3026 
3027 static inline int hrtick_enabled_dl(struct rq *rq)
3028 {
3029 	return 0;
3030 }
3031 
3032 static inline int hrtick_enabled(struct rq *rq)
3033 {
3034 	return 0;
3035 }
3036 
3037 #endif /* !CONFIG_SCHED_HRTICK */
3038 
3039 #ifndef arch_scale_freq_tick
3040 static __always_inline void arch_scale_freq_tick(void) { }
3041 #endif
3042 
3043 #ifndef arch_scale_freq_capacity
3044 /**
3045  * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
3046  * @cpu: the CPU in question.
3047  *
3048  * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
3049  *
3050  *     f_curr
3051  *     ------ * SCHED_CAPACITY_SCALE
3052  *     f_max
3053  */
3054 static __always_inline
3055 unsigned long arch_scale_freq_capacity(int cpu)
3056 {
3057 	return SCHED_CAPACITY_SCALE;
3058 }
3059 #endif
3060 
3061 /*
3062  * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to
3063  * acquire rq lock instead of rq_lock(). So at the end of these two functions
3064  * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of
3065  * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning.
3066  */
3067 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2)
3068 {
3069 	rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
3070 	rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
3071 }
3072 
3073 #define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...)				\
3074 __DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__)			\
3075 static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2)	\
3076 { class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t;			\
3077   _lock; return _t; }
3078 
3079 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2)
3080 {
3081 #ifdef CONFIG_SCHED_CORE
3082 	/*
3083 	 * In order to not have {0,2},{1,3} turn into into an AB-BA,
3084 	 * order by core-id first and cpu-id second.
3085 	 *
3086 	 * Notably:
3087 	 *
3088 	 *	double_rq_lock(0,3); will take core-0, core-1 lock
3089 	 *	double_rq_lock(1,2); will take core-1, core-0 lock
3090 	 *
3091 	 * when only cpu-id is considered.
3092 	 */
3093 	if (rq1->core->cpu < rq2->core->cpu)
3094 		return true;
3095 	if (rq1->core->cpu > rq2->core->cpu)
3096 		return false;
3097 
3098 	/*
3099 	 * __sched_core_flip() relies on SMT having cpu-id lock order.
3100 	 */
3101 #endif /* CONFIG_SCHED_CORE */
3102 	return rq1->cpu < rq2->cpu;
3103 }
3104 
3105 extern void double_rq_lock(struct rq *rq1, struct rq *rq2);
3106 
3107 #ifdef CONFIG_PREEMPTION
3108 
3109 /*
3110  * fair double_lock_balance: Safely acquires both rq->locks in a fair
3111  * way at the expense of forcing extra atomic operations in all
3112  * invocations.  This assures that the double_lock is acquired using the
3113  * same underlying policy as the spinlock_t on this architecture, which
3114  * reduces latency compared to the unfair variant below.  However, it
3115  * also adds more overhead and therefore may reduce throughput.
3116  */
3117 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
3118 	__releases(this_rq->lock)
3119 	__acquires(busiest->lock)
3120 	__acquires(this_rq->lock)
3121 {
3122 	raw_spin_rq_unlock(this_rq);
3123 	double_rq_lock(this_rq, busiest);
3124 
3125 	return 1;
3126 }
3127 
3128 #else /* !CONFIG_PREEMPTION: */
3129 /*
3130  * Unfair double_lock_balance: Optimizes throughput at the expense of
3131  * latency by eliminating extra atomic operations when the locks are
3132  * already in proper order on entry.  This favors lower CPU-ids and will
3133  * grant the double lock to lower CPUs over higher ids under contention,
3134  * regardless of entry order into the function.
3135  */
3136 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
3137 	__releases(this_rq->lock)
3138 	__acquires(busiest->lock)
3139 	__acquires(this_rq->lock)
3140 {
3141 	if (__rq_lockp(this_rq) == __rq_lockp(busiest) ||
3142 	    likely(raw_spin_rq_trylock(busiest))) {
3143 		double_rq_clock_clear_update(this_rq, busiest);
3144 		return 0;
3145 	}
3146 
3147 	if (rq_order_less(this_rq, busiest)) {
3148 		raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING);
3149 		double_rq_clock_clear_update(this_rq, busiest);
3150 		return 0;
3151 	}
3152 
3153 	raw_spin_rq_unlock(this_rq);
3154 	double_rq_lock(this_rq, busiest);
3155 
3156 	return 1;
3157 }
3158 
3159 #endif /* !CONFIG_PREEMPTION */
3160 
3161 /*
3162  * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
3163  */
3164 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
3165 {
3166 	lockdep_assert_irqs_disabled();
3167 
3168 	return _double_lock_balance(this_rq, busiest);
3169 }
3170 
3171 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
3172 	__releases(busiest->lock)
3173 {
3174 	if (__rq_lockp(this_rq) != __rq_lockp(busiest))
3175 		raw_spin_rq_unlock(busiest);
3176 	lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_);
3177 }
3178 
3179 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
3180 {
3181 	if (l1 > l2)
3182 		swap(l1, l2);
3183 
3184 	spin_lock(l1);
3185 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3186 }
3187 
3188 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
3189 {
3190 	if (l1 > l2)
3191 		swap(l1, l2);
3192 
3193 	spin_lock_irq(l1);
3194 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3195 }
3196 
3197 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
3198 {
3199 	if (l1 > l2)
3200 		swap(l1, l2);
3201 
3202 	raw_spin_lock(l1);
3203 	raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3204 }
3205 
3206 static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2)
3207 {
3208 	raw_spin_unlock(l1);
3209 	raw_spin_unlock(l2);
3210 }
3211 
3212 DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t,
3213 		    double_raw_lock(_T->lock, _T->lock2),
3214 		    double_raw_unlock(_T->lock, _T->lock2))
3215 
3216 /*
3217  * double_rq_unlock - safely unlock two runqueues
3218  *
3219  * Note this does not restore interrupts like task_rq_unlock,
3220  * you need to do so manually after calling.
3221  */
3222 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
3223 	__releases(rq1->lock)
3224 	__releases(rq2->lock)
3225 {
3226 	if (__rq_lockp(rq1) != __rq_lockp(rq2))
3227 		raw_spin_rq_unlock(rq2);
3228 	else
3229 		__release(rq2->lock);
3230 	raw_spin_rq_unlock(rq1);
3231 }
3232 
3233 extern void set_rq_online (struct rq *rq);
3234 extern void set_rq_offline(struct rq *rq);
3235 
3236 extern bool sched_smp_initialized;
3237 
3238 DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq,
3239 		    double_rq_lock(_T->lock, _T->lock2),
3240 		    double_rq_unlock(_T->lock, _T->lock2))
3241 
3242 extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq);
3243 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
3244 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
3245 
3246 extern bool sched_debug_verbose;
3247 
3248 extern void print_cfs_stats(struct seq_file *m, int cpu);
3249 extern void print_rt_stats(struct seq_file *m, int cpu);
3250 extern void print_dl_stats(struct seq_file *m, int cpu);
3251 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
3252 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
3253 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
3254 
3255 extern void resched_latency_warn(int cpu, u64 latency);
3256 
3257 #ifdef CONFIG_NUMA_BALANCING
3258 extern void show_numa_stats(struct task_struct *p, struct seq_file *m);
3259 extern void
3260 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
3261 		 unsigned long tpf, unsigned long gsf, unsigned long gpf);
3262 #endif /* CONFIG_NUMA_BALANCING */
3263 
3264 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
3265 extern void init_rt_rq(struct rt_rq *rt_rq);
3266 extern void init_dl_rq(struct dl_rq *dl_rq);
3267 
3268 extern void cfs_bandwidth_usage_inc(void);
3269 extern void cfs_bandwidth_usage_dec(void);
3270 
3271 #ifdef CONFIG_NO_HZ_COMMON
3272 
3273 #define NOHZ_BALANCE_KICK_BIT	0
3274 #define NOHZ_STATS_KICK_BIT	1
3275 #define NOHZ_NEWILB_KICK_BIT	2
3276 #define NOHZ_NEXT_KICK_BIT	3
3277 
3278 /* Run sched_balance_domains() */
3279 #define NOHZ_BALANCE_KICK	BIT(NOHZ_BALANCE_KICK_BIT)
3280 /* Update blocked load */
3281 #define NOHZ_STATS_KICK		BIT(NOHZ_STATS_KICK_BIT)
3282 /* Update blocked load when entering idle */
3283 #define NOHZ_NEWILB_KICK	BIT(NOHZ_NEWILB_KICK_BIT)
3284 /* Update nohz.next_balance */
3285 #define NOHZ_NEXT_KICK		BIT(NOHZ_NEXT_KICK_BIT)
3286 
3287 #define NOHZ_KICK_MASK		(NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK)
3288 
3289 #define nohz_flags(cpu)		(&cpu_rq(cpu)->nohz_flags)
3290 
3291 extern void nohz_balance_exit_idle(struct rq *rq);
3292 #else /* !CONFIG_NO_HZ_COMMON: */
3293 static inline void nohz_balance_exit_idle(struct rq *rq) { }
3294 #endif /* !CONFIG_NO_HZ_COMMON */
3295 
3296 #ifdef CONFIG_NO_HZ_COMMON
3297 extern void nohz_run_idle_balance(int cpu);
3298 #else
3299 static inline void nohz_run_idle_balance(int cpu) { }
3300 #endif
3301 
3302 #include "stats.h"
3303 
3304 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS)
3305 
3306 extern void __sched_core_account_forceidle(struct rq *rq);
3307 
3308 static inline void sched_core_account_forceidle(struct rq *rq)
3309 {
3310 	if (schedstat_enabled())
3311 		__sched_core_account_forceidle(rq);
3312 }
3313 
3314 extern void __sched_core_tick(struct rq *rq);
3315 
3316 static inline void sched_core_tick(struct rq *rq)
3317 {
3318 	if (sched_core_enabled(rq) && schedstat_enabled())
3319 		__sched_core_tick(rq);
3320 }
3321 
3322 #else /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS): */
3323 
3324 static inline void sched_core_account_forceidle(struct rq *rq) { }
3325 
3326 static inline void sched_core_tick(struct rq *rq) { }
3327 
3328 #endif /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS) */
3329 
3330 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
3331 
3332 struct irqtime {
3333 	u64			total;
3334 	u64			tick_delta;
3335 	u64			irq_start_time;
3336 	struct u64_stats_sync	sync;
3337 };
3338 
3339 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
3340 extern int sched_clock_irqtime;
3341 
3342 static inline int irqtime_enabled(void)
3343 {
3344 	return sched_clock_irqtime;
3345 }
3346 
3347 /*
3348  * Returns the irqtime minus the softirq time computed by ksoftirqd.
3349  * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime
3350  * and never move forward.
3351  */
3352 static inline u64 irq_time_read(int cpu)
3353 {
3354 	struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
3355 	unsigned int seq;
3356 	u64 total;
3357 
3358 	do {
3359 		seq = __u64_stats_fetch_begin(&irqtime->sync);
3360 		total = irqtime->total;
3361 	} while (__u64_stats_fetch_retry(&irqtime->sync, seq));
3362 
3363 	return total;
3364 }
3365 
3366 #else /* !CONFIG_IRQ_TIME_ACCOUNTING: */
3367 
3368 static inline int irqtime_enabled(void)
3369 {
3370 	return 0;
3371 }
3372 
3373 #endif /* !CONFIG_IRQ_TIME_ACCOUNTING */
3374 
3375 #ifdef CONFIG_CPU_FREQ
3376 
3377 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
3378 
3379 /**
3380  * cpufreq_update_util - Take a note about CPU utilization changes.
3381  * @rq: Runqueue to carry out the update for.
3382  * @flags: Update reason flags.
3383  *
3384  * This function is called by the scheduler on the CPU whose utilization is
3385  * being updated.
3386  *
3387  * It can only be called from RCU-sched read-side critical sections.
3388  *
3389  * The way cpufreq is currently arranged requires it to evaluate the CPU
3390  * performance state (frequency/voltage) on a regular basis to prevent it from
3391  * being stuck in a completely inadequate performance level for too long.
3392  * That is not guaranteed to happen if the updates are only triggered from CFS
3393  * and DL, though, because they may not be coming in if only RT tasks are
3394  * active all the time (or there are RT tasks only).
3395  *
3396  * As a workaround for that issue, this function is called periodically by the
3397  * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
3398  * but that really is a band-aid.  Going forward it should be replaced with
3399  * solutions targeted more specifically at RT tasks.
3400  */
3401 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
3402 {
3403 	struct update_util_data *data;
3404 
3405 	data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
3406 						  cpu_of(rq)));
3407 	if (data)
3408 		data->func(data, rq_clock(rq), flags);
3409 }
3410 #else /* !CONFIG_CPU_FREQ: */
3411 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) { }
3412 #endif /* !CONFIG_CPU_FREQ */
3413 
3414 #ifdef arch_scale_freq_capacity
3415 # ifndef arch_scale_freq_invariant
3416 #  define arch_scale_freq_invariant()	true
3417 # endif
3418 #else
3419 # define arch_scale_freq_invariant()	false
3420 #endif
3421 
3422 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
3423 				 unsigned long *min,
3424 				 unsigned long *max);
3425 
3426 unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual,
3427 				 unsigned long min,
3428 				 unsigned long max);
3429 
3430 
3431 /*
3432  * Verify the fitness of task @p to run on @cpu taking into account the
3433  * CPU original capacity and the runtime/deadline ratio of the task.
3434  *
3435  * The function will return true if the original capacity of @cpu is
3436  * greater than or equal to task's deadline density right shifted by
3437  * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise.
3438  */
3439 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
3440 {
3441 	unsigned long cap = arch_scale_cpu_capacity(cpu);
3442 
3443 	return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT);
3444 }
3445 
3446 static inline unsigned long cpu_bw_dl(struct rq *rq)
3447 {
3448 	return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
3449 }
3450 
3451 static inline unsigned long cpu_util_dl(struct rq *rq)
3452 {
3453 	return READ_ONCE(rq->avg_dl.util_avg);
3454 }
3455 
3456 
3457 extern unsigned long cpu_util_cfs(int cpu);
3458 extern unsigned long cpu_util_cfs_boost(int cpu);
3459 
3460 static inline unsigned long cpu_util_rt(struct rq *rq)
3461 {
3462 	return READ_ONCE(rq->avg_rt.util_avg);
3463 }
3464 
3465 #ifdef CONFIG_UCLAMP_TASK
3466 
3467 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
3468 
3469 /*
3470  * When uclamp is compiled in, the aggregation at rq level is 'turned off'
3471  * by default in the fast path and only gets turned on once userspace performs
3472  * an operation that requires it.
3473  *
3474  * Returns true if userspace opted-in to use uclamp and aggregation at rq level
3475  * hence is active.
3476  */
3477 static inline bool uclamp_is_used(void)
3478 {
3479 	return static_branch_likely(&sched_uclamp_used);
3480 }
3481 
3482 /*
3483  * Enabling static branches would get the cpus_read_lock(),
3484  * check whether uclamp_is_used before enable it to avoid always
3485  * calling cpus_read_lock(). Because we never disable this
3486  * static key once enable it.
3487  */
3488 static inline void sched_uclamp_enable(void)
3489 {
3490 	if (!uclamp_is_used())
3491 		static_branch_enable(&sched_uclamp_used);
3492 }
3493 
3494 static inline unsigned long uclamp_rq_get(struct rq *rq,
3495 					  enum uclamp_id clamp_id)
3496 {
3497 	return READ_ONCE(rq->uclamp[clamp_id].value);
3498 }
3499 
3500 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id,
3501 				 unsigned int value)
3502 {
3503 	WRITE_ONCE(rq->uclamp[clamp_id].value, value);
3504 }
3505 
3506 static inline bool uclamp_rq_is_idle(struct rq *rq)
3507 {
3508 	return rq->uclamp_flags & UCLAMP_FLAG_IDLE;
3509 }
3510 
3511 /* Is the rq being capped/throttled by uclamp_max? */
3512 static inline bool uclamp_rq_is_capped(struct rq *rq)
3513 {
3514 	unsigned long rq_util;
3515 	unsigned long max_util;
3516 
3517 	if (!uclamp_is_used())
3518 		return false;
3519 
3520 	rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq);
3521 	max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
3522 
3523 	return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util;
3524 }
3525 
3526 #define for_each_clamp_id(clamp_id) \
3527 	for ((clamp_id) = 0; (clamp_id) < UCLAMP_CNT; (clamp_id)++)
3528 
3529 extern unsigned int sysctl_sched_uclamp_util_min_rt_default;
3530 
3531 
3532 static inline unsigned int uclamp_none(enum uclamp_id clamp_id)
3533 {
3534 	if (clamp_id == UCLAMP_MIN)
3535 		return 0;
3536 	return SCHED_CAPACITY_SCALE;
3537 }
3538 
3539 /* Integer rounded range for each bucket */
3540 #define UCLAMP_BUCKET_DELTA DIV_ROUND_CLOSEST(SCHED_CAPACITY_SCALE, UCLAMP_BUCKETS)
3541 
3542 static inline unsigned int uclamp_bucket_id(unsigned int clamp_value)
3543 {
3544 	return min_t(unsigned int, clamp_value / UCLAMP_BUCKET_DELTA, UCLAMP_BUCKETS - 1);
3545 }
3546 
3547 static inline void
3548 uclamp_se_set(struct uclamp_se *uc_se, unsigned int value, bool user_defined)
3549 {
3550 	uc_se->value = value;
3551 	uc_se->bucket_id = uclamp_bucket_id(value);
3552 	uc_se->user_defined = user_defined;
3553 }
3554 
3555 #else /* !CONFIG_UCLAMP_TASK: */
3556 
3557 static inline unsigned long
3558 uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id)
3559 {
3560 	if (clamp_id == UCLAMP_MIN)
3561 		return 0;
3562 
3563 	return SCHED_CAPACITY_SCALE;
3564 }
3565 
3566 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; }
3567 
3568 static inline bool uclamp_is_used(void)
3569 {
3570 	return false;
3571 }
3572 
3573 static inline void sched_uclamp_enable(void) {}
3574 
3575 static inline unsigned long
3576 uclamp_rq_get(struct rq *rq, enum uclamp_id clamp_id)
3577 {
3578 	if (clamp_id == UCLAMP_MIN)
3579 		return 0;
3580 
3581 	return SCHED_CAPACITY_SCALE;
3582 }
3583 
3584 static inline void
3585 uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, unsigned int value)
3586 {
3587 }
3588 
3589 static inline bool uclamp_rq_is_idle(struct rq *rq)
3590 {
3591 	return false;
3592 }
3593 
3594 #endif /* !CONFIG_UCLAMP_TASK */
3595 
3596 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
3597 
3598 static inline unsigned long cpu_util_irq(struct rq *rq)
3599 {
3600 	return READ_ONCE(rq->avg_irq.util_avg);
3601 }
3602 
3603 static inline
3604 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3605 {
3606 	util *= (max - irq);
3607 	util /= max;
3608 
3609 	return util;
3610 
3611 }
3612 
3613 #else /* !CONFIG_HAVE_SCHED_AVG_IRQ: */
3614 
3615 static inline unsigned long cpu_util_irq(struct rq *rq)
3616 {
3617 	return 0;
3618 }
3619 
3620 static inline
3621 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3622 {
3623 	return util;
3624 }
3625 
3626 #endif /* !CONFIG_HAVE_SCHED_AVG_IRQ */
3627 
3628 extern void __setparam_fair(struct task_struct *p, const struct sched_attr *attr);
3629 
3630 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
3631 
3632 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
3633 
3634 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
3635 
3636 static inline bool sched_energy_enabled(void)
3637 {
3638 	return static_branch_unlikely(&sched_energy_present);
3639 }
3640 
3641 #else /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL): */
3642 
3643 #define perf_domain_span(pd) NULL
3644 
3645 static inline bool sched_energy_enabled(void) { return false; }
3646 
3647 #endif /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
3648 
3649 #ifdef CONFIG_MEMBARRIER
3650 
3651 /*
3652  * The scheduler provides memory barriers required by membarrier between:
3653  * - prior user-space memory accesses and store to rq->membarrier_state,
3654  * - store to rq->membarrier_state and following user-space memory accesses.
3655  * In the same way it provides those guarantees around store to rq->curr.
3656  */
3657 static inline void membarrier_switch_mm(struct rq *rq,
3658 					struct mm_struct *prev_mm,
3659 					struct mm_struct *next_mm)
3660 {
3661 	int membarrier_state;
3662 
3663 	if (prev_mm == next_mm)
3664 		return;
3665 
3666 	membarrier_state = atomic_read(&next_mm->membarrier_state);
3667 	if (READ_ONCE(rq->membarrier_state) == membarrier_state)
3668 		return;
3669 
3670 	WRITE_ONCE(rq->membarrier_state, membarrier_state);
3671 }
3672 
3673 #else /* !CONFIG_MEMBARRIER: */
3674 
3675 static inline void membarrier_switch_mm(struct rq *rq,
3676 					struct mm_struct *prev_mm,
3677 					struct mm_struct *next_mm)
3678 {
3679 }
3680 
3681 #endif /* !CONFIG_MEMBARRIER */
3682 
3683 static inline bool is_per_cpu_kthread(struct task_struct *p)
3684 {
3685 	if (!(p->flags & PF_KTHREAD))
3686 		return false;
3687 
3688 	if (p->nr_cpus_allowed != 1)
3689 		return false;
3690 
3691 	return true;
3692 }
3693 
3694 extern void swake_up_all_locked(struct swait_queue_head *q);
3695 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
3696 
3697 extern int try_to_wake_up(struct task_struct *tsk, unsigned int state, int wake_flags);
3698 
3699 #ifdef CONFIG_PREEMPT_DYNAMIC
3700 extern int preempt_dynamic_mode;
3701 extern int sched_dynamic_mode(const char *str);
3702 extern void sched_dynamic_update(int mode);
3703 #endif
3704 extern const char *preempt_modes[];
3705 
3706 #ifdef CONFIG_SCHED_MM_CID
3707 
3708 static __always_inline bool cid_on_cpu(unsigned int cid)
3709 {
3710 	return cid & MM_CID_ONCPU;
3711 }
3712 
3713 static __always_inline bool cid_in_transit(unsigned int cid)
3714 {
3715 	return cid & MM_CID_TRANSIT;
3716 }
3717 
3718 static __always_inline unsigned int cpu_cid_to_cid(unsigned int cid)
3719 {
3720 	return cid & ~MM_CID_ONCPU;
3721 }
3722 
3723 static __always_inline unsigned int cid_to_cpu_cid(unsigned int cid)
3724 {
3725 	return cid | MM_CID_ONCPU;
3726 }
3727 
3728 static __always_inline unsigned int cid_to_transit_cid(unsigned int cid)
3729 {
3730 	return cid | MM_CID_TRANSIT;
3731 }
3732 
3733 static __always_inline unsigned int cid_from_transit_cid(unsigned int cid)
3734 {
3735 	return cid & ~MM_CID_TRANSIT;
3736 }
3737 
3738 static __always_inline bool cid_on_task(unsigned int cid)
3739 {
3740 	/* True if none of the MM_CID_ONCPU, MM_CID_TRANSIT, MM_CID_UNSET bits is set */
3741 	return cid < MM_CID_TRANSIT;
3742 }
3743 
3744 static __always_inline void mm_drop_cid(struct mm_struct *mm, unsigned int cid)
3745 {
3746 	clear_bit(cid, mm_cidmask(mm));
3747 }
3748 
3749 static __always_inline void mm_unset_cid_on_task(struct task_struct *t)
3750 {
3751 	unsigned int cid = t->mm_cid.cid;
3752 
3753 	t->mm_cid.cid = MM_CID_UNSET;
3754 	if (cid_on_task(cid))
3755 		mm_drop_cid(t->mm, cid);
3756 }
3757 
3758 static __always_inline void mm_drop_cid_on_cpu(struct mm_struct *mm, struct mm_cid_pcpu *pcp)
3759 {
3760 	/* Clear the ONCPU bit, but do not set UNSET in the per CPU storage */
3761 	pcp->cid = cpu_cid_to_cid(pcp->cid);
3762 	mm_drop_cid(mm, pcp->cid);
3763 }
3764 
3765 static inline unsigned int __mm_get_cid(struct mm_struct *mm, unsigned int max_cids)
3766 {
3767 	unsigned int cid = find_first_zero_bit(mm_cidmask(mm), max_cids);
3768 
3769 	if (cid >= max_cids)
3770 		return MM_CID_UNSET;
3771 	if (test_and_set_bit(cid, mm_cidmask(mm)))
3772 		return MM_CID_UNSET;
3773 	return cid;
3774 }
3775 
3776 static inline unsigned int mm_get_cid(struct mm_struct *mm)
3777 {
3778 	unsigned int cid = __mm_get_cid(mm, READ_ONCE(mm->mm_cid.max_cids));
3779 
3780 	while (cid == MM_CID_UNSET) {
3781 		cpu_relax();
3782 		cid = __mm_get_cid(mm, num_possible_cpus());
3783 	}
3784 	return cid;
3785 }
3786 
3787 static inline unsigned int mm_cid_converge(struct mm_struct *mm, unsigned int orig_cid,
3788 					   unsigned int max_cids)
3789 {
3790 	unsigned int new_cid, cid = cpu_cid_to_cid(orig_cid);
3791 
3792 	/* Is it in the optimal CID space? */
3793 	if (likely(cid < max_cids))
3794 		return orig_cid;
3795 
3796 	/* Try to find one in the optimal space. Otherwise keep the provided. */
3797 	new_cid = __mm_get_cid(mm, max_cids);
3798 	if (new_cid != MM_CID_UNSET) {
3799 		mm_drop_cid(mm, cid);
3800 		/* Preserve the ONCPU mode of the original CID */
3801 		return new_cid | (orig_cid & MM_CID_ONCPU);
3802 	}
3803 	return orig_cid;
3804 }
3805 
3806 static __always_inline void mm_cid_update_task_cid(struct task_struct *t, unsigned int cid)
3807 {
3808 	if (t->mm_cid.cid != cid) {
3809 		t->mm_cid.cid = cid;
3810 		rseq_sched_set_ids_changed(t);
3811 	}
3812 }
3813 
3814 static __always_inline void mm_cid_update_pcpu_cid(struct mm_struct *mm, unsigned int cid)
3815 {
3816 	__this_cpu_write(mm->mm_cid.pcpu->cid, cid);
3817 }
3818 
3819 static __always_inline void mm_cid_from_cpu(struct task_struct *t, unsigned int cpu_cid)
3820 {
3821 	unsigned int max_cids, tcid = t->mm_cid.cid;
3822 	struct mm_struct *mm = t->mm;
3823 
3824 	max_cids = READ_ONCE(mm->mm_cid.max_cids);
3825 	/* Optimize for the common case where both have the ONCPU bit set */
3826 	if (likely(cid_on_cpu(cpu_cid & tcid))) {
3827 		if (likely(cpu_cid_to_cid(cpu_cid) < max_cids)) {
3828 			mm_cid_update_task_cid(t, cpu_cid);
3829 			return;
3830 		}
3831 		/* Try to converge into the optimal CID space */
3832 		cpu_cid = mm_cid_converge(mm, cpu_cid, max_cids);
3833 	} else {
3834 		/* Hand over or drop the task owned CID */
3835 		if (cid_on_task(tcid)) {
3836 			if (cid_on_cpu(cpu_cid))
3837 				mm_unset_cid_on_task(t);
3838 			else
3839 				cpu_cid = cid_to_cpu_cid(tcid);
3840 		}
3841 		/* Still nothing, allocate a new one */
3842 		if (!cid_on_cpu(cpu_cid))
3843 			cpu_cid = cid_to_cpu_cid(mm_get_cid(mm));
3844 	}
3845 	mm_cid_update_pcpu_cid(mm, cpu_cid);
3846 	mm_cid_update_task_cid(t, cpu_cid);
3847 }
3848 
3849 static __always_inline void mm_cid_from_task(struct task_struct *t, unsigned int cpu_cid)
3850 {
3851 	unsigned int max_cids, tcid = t->mm_cid.cid;
3852 	struct mm_struct *mm = t->mm;
3853 
3854 	max_cids = READ_ONCE(mm->mm_cid.max_cids);
3855 	/* Optimize for the common case, where both have the ONCPU bit clear */
3856 	if (likely(cid_on_task(tcid | cpu_cid))) {
3857 		if (likely(tcid < max_cids)) {
3858 			mm_cid_update_pcpu_cid(mm, tcid);
3859 			return;
3860 		}
3861 		/* Try to converge into the optimal CID space */
3862 		tcid = mm_cid_converge(mm, tcid, max_cids);
3863 	} else {
3864 		/* Hand over or drop the CPU owned CID */
3865 		if (cid_on_cpu(cpu_cid)) {
3866 			if (cid_on_task(tcid))
3867 				mm_drop_cid_on_cpu(mm, this_cpu_ptr(mm->mm_cid.pcpu));
3868 			else
3869 				tcid = cpu_cid_to_cid(cpu_cid);
3870 		}
3871 		/* Still nothing, allocate a new one */
3872 		if (!cid_on_task(tcid))
3873 			tcid = mm_get_cid(mm);
3874 		/* Set the transition mode flag if required */
3875 		tcid |= READ_ONCE(mm->mm_cid.transit);
3876 	}
3877 	mm_cid_update_pcpu_cid(mm, tcid);
3878 	mm_cid_update_task_cid(t, tcid);
3879 }
3880 
3881 static __always_inline void mm_cid_schedin(struct task_struct *next)
3882 {
3883 	struct mm_struct *mm = next->mm;
3884 	unsigned int cpu_cid;
3885 
3886 	if (!next->mm_cid.active)
3887 		return;
3888 
3889 	cpu_cid = __this_cpu_read(mm->mm_cid.pcpu->cid);
3890 	if (likely(!READ_ONCE(mm->mm_cid.percpu)))
3891 		mm_cid_from_task(next, cpu_cid);
3892 	else
3893 		mm_cid_from_cpu(next, cpu_cid);
3894 }
3895 
3896 static __always_inline void mm_cid_schedout(struct task_struct *prev)
3897 {
3898 	/* During mode transitions CIDs are temporary and need to be dropped */
3899 	if (likely(!cid_in_transit(prev->mm_cid.cid)))
3900 		return;
3901 
3902 	mm_drop_cid(prev->mm, cid_from_transit_cid(prev->mm_cid.cid));
3903 	prev->mm_cid.cid = MM_CID_UNSET;
3904 }
3905 
3906 static inline void mm_cid_switch_to(struct task_struct *prev, struct task_struct *next)
3907 {
3908 	mm_cid_schedout(prev);
3909 	mm_cid_schedin(next);
3910 }
3911 
3912 #else /* !CONFIG_SCHED_MM_CID: */
3913 static inline void mm_cid_switch_to(struct task_struct *prev, struct task_struct *next) { }
3914 #endif /* !CONFIG_SCHED_MM_CID */
3915 
3916 extern u64 avg_vruntime(struct cfs_rq *cfs_rq);
3917 extern int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se);
3918 static inline
3919 void move_queued_task_locked(struct rq *src_rq, struct rq *dst_rq, struct task_struct *task)
3920 {
3921 	lockdep_assert_rq_held(src_rq);
3922 	lockdep_assert_rq_held(dst_rq);
3923 
3924 	deactivate_task(src_rq, task, 0);
3925 	set_task_cpu(task, dst_rq->cpu);
3926 	activate_task(dst_rq, task, 0);
3927 }
3928 
3929 static inline
3930 bool task_is_pushable(struct rq *rq, struct task_struct *p, int cpu)
3931 {
3932 	if (!task_on_cpu(rq, p) &&
3933 	    cpumask_test_cpu(cpu, &p->cpus_mask))
3934 		return true;
3935 
3936 	return false;
3937 }
3938 
3939 #ifdef CONFIG_RT_MUTEXES
3940 
3941 static inline int __rt_effective_prio(struct task_struct *pi_task, int prio)
3942 {
3943 	if (pi_task)
3944 		prio = min(prio, pi_task->prio);
3945 
3946 	return prio;
3947 }
3948 
3949 static inline int rt_effective_prio(struct task_struct *p, int prio)
3950 {
3951 	struct task_struct *pi_task = rt_mutex_get_top_task(p);
3952 
3953 	return __rt_effective_prio(pi_task, prio);
3954 }
3955 
3956 #else /* !CONFIG_RT_MUTEXES: */
3957 
3958 static inline int rt_effective_prio(struct task_struct *p, int prio)
3959 {
3960 	return prio;
3961 }
3962 
3963 #endif /* !CONFIG_RT_MUTEXES */
3964 
3965 extern int __sched_setscheduler(struct task_struct *p, const struct sched_attr *attr, bool user, bool pi);
3966 extern int __sched_setaffinity(struct task_struct *p, struct affinity_context *ctx);
3967 extern const struct sched_class *__setscheduler_class(int policy, int prio);
3968 extern void set_load_weight(struct task_struct *p, bool update_load);
3969 extern void enqueue_task(struct rq *rq, struct task_struct *p, int flags);
3970 extern bool dequeue_task(struct rq *rq, struct task_struct *p, int flags);
3971 
3972 extern struct balance_callback *splice_balance_callbacks(struct rq *rq);
3973 
3974 extern void __balance_callbacks(struct rq *rq, struct rq_flags *rf);
3975 extern void balance_callbacks(struct rq *rq, struct balance_callback *head);
3976 
3977 /*
3978  * The 'sched_change' pattern is the safe, easy and slow way of changing a
3979  * task's scheduling properties. It dequeues a task, such that the scheduler
3980  * is fully unaware of it; at which point its properties can be modified;
3981  * after which it is enqueued again.
3982  *
3983  * Typically this must be called while holding task_rq_lock, since most/all
3984  * properties are serialized under those locks. There is currently one
3985  * exception to this rule in sched/ext which only holds rq->lock.
3986  */
3987 
3988 /*
3989  * This structure is a temporary, used to preserve/convey the queueing state
3990  * of the task between sched_change_begin() and sched_change_end(). Ensuring
3991  * the task's queueing state is idempotent across the operation.
3992  */
3993 struct sched_change_ctx {
3994 	u64			prio;
3995 	struct task_struct	*p;
3996 	int			flags;
3997 	bool			queued;
3998 	bool			running;
3999 };
4000 
4001 struct sched_change_ctx *sched_change_begin(struct task_struct *p, unsigned int flags);
4002 void sched_change_end(struct sched_change_ctx *ctx);
4003 
4004 DEFINE_CLASS(sched_change, struct sched_change_ctx *,
4005 	     sched_change_end(_T),
4006 	     sched_change_begin(p, flags),
4007 	     struct task_struct *p, unsigned int flags)
4008 
4009 DEFINE_CLASS_IS_UNCONDITIONAL(sched_change)
4010 
4011 #include "ext.h"
4012 
4013 #endif /* _KERNEL_SCHED_SCHED_H */
4014