1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Scheduler internal types and methods:
4  */
5 #include <linux/sched.h>
6 
7 #include <linux/sched/autogroup.h>
8 #include <linux/sched/clock.h>
9 #include <linux/sched/coredump.h>
10 #include <linux/sched/cpufreq.h>
11 #include <linux/sched/cputime.h>
12 #include <linux/sched/deadline.h>
13 #include <linux/sched/debug.h>
14 #include <linux/sched/hotplug.h>
15 #include <linux/sched/idle.h>
16 #include <linux/sched/init.h>
17 #include <linux/sched/isolation.h>
18 #include <linux/sched/jobctl.h>
19 #include <linux/sched/loadavg.h>
20 #include <linux/sched/mm.h>
21 #include <linux/sched/nohz.h>
22 #include <linux/sched/numa_balancing.h>
23 #include <linux/sched/prio.h>
24 #include <linux/sched/rt.h>
25 #include <linux/sched/signal.h>
26 #include <linux/sched/smt.h>
27 #include <linux/sched/stat.h>
28 #include <linux/sched/sysctl.h>
29 #include <linux/sched/task.h>
30 #include <linux/sched/task_stack.h>
31 #include <linux/sched/topology.h>
32 #include <linux/sched/user.h>
33 #include <linux/sched/wake_q.h>
34 #include <linux/sched/xacct.h>
35 
36 #include <uapi/linux/sched/types.h>
37 
38 #include <linux/binfmts.h>
39 #include <linux/bitops.h>
40 #include <linux/compat.h>
41 #include <linux/context_tracking.h>
42 #include <linux/cpufreq.h>
43 #include <linux/cpuidle.h>
44 #include <linux/cpuset.h>
45 #include <linux/ctype.h>
46 #include <linux/debugfs.h>
47 #include <linux/delayacct.h>
48 #include <linux/energy_model.h>
49 #include <linux/init_task.h>
50 #include <linux/kprobes.h>
51 #include <linux/kthread.h>
52 #include <linux/membarrier.h>
53 #include <linux/migrate.h>
54 #include <linux/mmu_context.h>
55 #include <linux/nmi.h>
56 #include <linux/proc_fs.h>
57 #include <linux/prefetch.h>
58 #include <linux/profile.h>
59 #include <linux/psi.h>
60 #include <linux/ratelimit.h>
61 #include <linux/rcupdate_wait.h>
62 #include <linux/security.h>
63 #include <linux/stop_machine.h>
64 #include <linux/suspend.h>
65 #include <linux/swait.h>
66 #include <linux/syscalls.h>
67 #include <linux/task_work.h>
68 #include <linux/tsacct_kern.h>
69 
70 #include <asm/tlb.h>
71 
72 #ifdef CONFIG_PARAVIRT
73 # include <asm/paravirt.h>
74 #endif
75 
76 #include "cpupri.h"
77 #include "cpudeadline.h"
78 
79 #include <trace/events/sched.h>
80 
81 #ifdef CONFIG_SCHED_DEBUG
82 # define SCHED_WARN_ON(x)	WARN_ONCE(x, #x)
83 #else
84 # define SCHED_WARN_ON(x)	({ (void)(x), 0; })
85 #endif
86 
87 struct rq;
88 struct cpuidle_state;
89 
90 /* task_struct::on_rq states: */
91 #define TASK_ON_RQ_QUEUED	1
92 #define TASK_ON_RQ_MIGRATING	2
93 
94 extern __read_mostly int scheduler_running;
95 
96 extern unsigned long calc_load_update;
97 extern atomic_long_t calc_load_tasks;
98 
99 extern void calc_global_load_tick(struct rq *this_rq);
100 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
101 
102 extern void call_trace_sched_update_nr_running(struct rq *rq, int count);
103 /*
104  * Helpers for converting nanosecond timing to jiffy resolution
105  */
106 #define NS_TO_JIFFIES(TIME)	((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
107 
108 /*
109  * Increase resolution of nice-level calculations for 64-bit architectures.
110  * The extra resolution improves shares distribution and load balancing of
111  * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
112  * hierarchies, especially on larger systems. This is not a user-visible change
113  * and does not change the user-interface for setting shares/weights.
114  *
115  * We increase resolution only if we have enough bits to allow this increased
116  * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
117  * are pretty high and the returns do not justify the increased costs.
118  *
119  * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
120  * increase coverage and consistency always enable it on 64-bit platforms.
121  */
122 #ifdef CONFIG_64BIT
123 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
124 # define scale_load(w)		((w) << SCHED_FIXEDPOINT_SHIFT)
125 # define scale_load_down(w) \
126 ({ \
127 	unsigned long __w = (w); \
128 	if (__w) \
129 		__w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \
130 	__w; \
131 })
132 #else
133 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT)
134 # define scale_load(w)		(w)
135 # define scale_load_down(w)	(w)
136 #endif
137 
138 /*
139  * Task weight (visible to users) and its load (invisible to users) have
140  * independent resolution, but they should be well calibrated. We use
141  * scale_load() and scale_load_down(w) to convert between them. The
142  * following must be true:
143  *
144  *  scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD
145  *
146  */
147 #define NICE_0_LOAD		(1L << NICE_0_LOAD_SHIFT)
148 
149 /*
150  * Single value that decides SCHED_DEADLINE internal math precision.
151  * 10 -> just above 1us
152  * 9  -> just above 0.5us
153  */
154 #define DL_SCALE		10
155 
156 /*
157  * Single value that denotes runtime == period, ie unlimited time.
158  */
159 #define RUNTIME_INF		((u64)~0ULL)
160 
idle_policy(int policy)161 static inline int idle_policy(int policy)
162 {
163 	return policy == SCHED_IDLE;
164 }
fair_policy(int policy)165 static inline int fair_policy(int policy)
166 {
167 	return policy == SCHED_NORMAL || policy == SCHED_BATCH;
168 }
169 
rt_policy(int policy)170 static inline int rt_policy(int policy)
171 {
172 	return policy == SCHED_FIFO || policy == SCHED_RR;
173 }
174 
dl_policy(int policy)175 static inline int dl_policy(int policy)
176 {
177 	return policy == SCHED_DEADLINE;
178 }
valid_policy(int policy)179 static inline bool valid_policy(int policy)
180 {
181 	return idle_policy(policy) || fair_policy(policy) ||
182 		rt_policy(policy) || dl_policy(policy);
183 }
184 
task_has_idle_policy(struct task_struct * p)185 static inline int task_has_idle_policy(struct task_struct *p)
186 {
187 	return idle_policy(p->policy);
188 }
189 
task_has_rt_policy(struct task_struct * p)190 static inline int task_has_rt_policy(struct task_struct *p)
191 {
192 	return rt_policy(p->policy);
193 }
194 
task_has_dl_policy(struct task_struct * p)195 static inline int task_has_dl_policy(struct task_struct *p)
196 {
197 	return dl_policy(p->policy);
198 }
199 
200 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
201 
update_avg(u64 * avg,u64 sample)202 static inline void update_avg(u64 *avg, u64 sample)
203 {
204 	s64 diff = sample - *avg;
205 	*avg += diff / 8;
206 }
207 
208 /*
209  * Shifting a value by an exponent greater *or equal* to the size of said value
210  * is UB; cap at size-1.
211  */
212 #define shr_bound(val, shift)							\
213 	(val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1))
214 
215 /*
216  * !! For sched_setattr_nocheck() (kernel) only !!
217  *
218  * This is actually gross. :(
219  *
220  * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
221  * tasks, but still be able to sleep. We need this on platforms that cannot
222  * atomically change clock frequency. Remove once fast switching will be
223  * available on such platforms.
224  *
225  * SUGOV stands for SchedUtil GOVernor.
226  */
227 #define SCHED_FLAG_SUGOV	0x10000000
228 
229 #define SCHED_DL_FLAGS (SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV)
230 
dl_entity_is_special(struct sched_dl_entity * dl_se)231 static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se)
232 {
233 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
234 	return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
235 #else
236 	return false;
237 #endif
238 }
239 
240 /*
241  * Tells if entity @a should preempt entity @b.
242  */
243 static inline bool
dl_entity_preempt(struct sched_dl_entity * a,struct sched_dl_entity * b)244 dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
245 {
246 	return dl_entity_is_special(a) ||
247 	       dl_time_before(a->deadline, b->deadline);
248 }
249 
250 /*
251  * This is the priority-queue data structure of the RT scheduling class:
252  */
253 struct rt_prio_array {
254 	DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
255 	struct list_head queue[MAX_RT_PRIO];
256 };
257 
258 struct rt_bandwidth {
259 	/* nests inside the rq lock: */
260 	raw_spinlock_t		rt_runtime_lock;
261 	ktime_t			rt_period;
262 	u64			rt_runtime;
263 	struct hrtimer		rt_period_timer;
264 	unsigned int		rt_period_active;
265 };
266 
267 void __dl_clear_params(struct task_struct *p);
268 
269 struct dl_bandwidth {
270 	raw_spinlock_t		dl_runtime_lock;
271 	u64			dl_runtime;
272 	u64			dl_period;
273 };
274 
dl_bandwidth_enabled(void)275 static inline int dl_bandwidth_enabled(void)
276 {
277 	return sysctl_sched_rt_runtime >= 0;
278 }
279 
280 /*
281  * To keep the bandwidth of -deadline tasks under control
282  * we need some place where:
283  *  - store the maximum -deadline bandwidth of each cpu;
284  *  - cache the fraction of bandwidth that is currently allocated in
285  *    each root domain;
286  *
287  * This is all done in the data structure below. It is similar to the
288  * one used for RT-throttling (rt_bandwidth), with the main difference
289  * that, since here we are only interested in admission control, we
290  * do not decrease any runtime while the group "executes", neither we
291  * need a timer to replenish it.
292  *
293  * With respect to SMP, bandwidth is given on a per root domain basis,
294  * meaning that:
295  *  - bw (< 100%) is the deadline bandwidth of each CPU;
296  *  - total_bw is the currently allocated bandwidth in each root domain;
297  */
298 struct dl_bw {
299 	raw_spinlock_t		lock;
300 	u64			bw;
301 	u64			total_bw;
302 };
303 
304 static inline void __dl_update(struct dl_bw *dl_b, s64 bw);
305 
306 static inline
__dl_sub(struct dl_bw * dl_b,u64 tsk_bw,int cpus)307 void __dl_sub(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
308 {
309 	dl_b->total_bw -= tsk_bw;
310 	__dl_update(dl_b, (s32)tsk_bw / cpus);
311 }
312 
313 static inline
__dl_add(struct dl_bw * dl_b,u64 tsk_bw,int cpus)314 void __dl_add(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
315 {
316 	dl_b->total_bw += tsk_bw;
317 	__dl_update(dl_b, -((s32)tsk_bw / cpus));
318 }
319 
__dl_overflow(struct dl_bw * dl_b,unsigned long cap,u64 old_bw,u64 new_bw)320 static inline bool __dl_overflow(struct dl_bw *dl_b, unsigned long cap,
321 				 u64 old_bw, u64 new_bw)
322 {
323 	return dl_b->bw != -1 &&
324 	       cap_scale(dl_b->bw, cap) < dl_b->total_bw - old_bw + new_bw;
325 }
326 
327 /*
328  * Verify the fitness of task @p to run on @cpu taking into account the
329  * CPU original capacity and the runtime/deadline ratio of the task.
330  *
331  * The function will return true if the CPU original capacity of the
332  * @cpu scaled by SCHED_CAPACITY_SCALE >= runtime/deadline ratio of the
333  * task and false otherwise.
334  */
dl_task_fits_capacity(struct task_struct * p,int cpu)335 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
336 {
337 	unsigned long cap = arch_scale_cpu_capacity(cpu);
338 
339 	return cap_scale(p->dl.dl_deadline, cap) >= p->dl.dl_runtime;
340 }
341 
342 extern void init_dl_bw(struct dl_bw *dl_b);
343 extern int  sched_dl_global_validate(void);
344 extern void sched_dl_do_global(void);
345 extern int  sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
346 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
347 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
348 extern bool __checkparam_dl(const struct sched_attr *attr);
349 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
350 extern int  dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
351 extern int  dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
352 extern bool dl_cpu_busy(unsigned int cpu);
353 
354 #ifdef CONFIG_CGROUP_SCHED
355 
356 #include <linux/cgroup.h>
357 #include <linux/psi.h>
358 
359 struct cfs_rq;
360 struct rt_rq;
361 
362 extern struct list_head task_groups;
363 
364 struct cfs_bandwidth {
365 #ifdef CONFIG_CFS_BANDWIDTH
366 	raw_spinlock_t		lock;
367 	ktime_t			period;
368 	u64			quota;
369 	u64			runtime;
370 	u64			burst;
371 	u64			runtime_snap;
372 	s64			hierarchical_quota;
373 
374 	u8			idle;
375 	u8			period_active;
376 	u8			slack_started;
377 	struct hrtimer		period_timer;
378 	struct hrtimer		slack_timer;
379 	struct list_head	throttled_cfs_rq;
380 
381 	/* Statistics: */
382 	int			nr_periods;
383 	int			nr_throttled;
384 	int			nr_burst;
385 	u64			throttled_time;
386 	u64			burst_time;
387 #endif
388 };
389 
390 /* Task group related information */
391 struct task_group {
392 	struct cgroup_subsys_state css;
393 
394 #ifdef CONFIG_FAIR_GROUP_SCHED
395 	/* schedulable entities of this group on each CPU */
396 	struct sched_entity	**se;
397 	/* runqueue "owned" by this group on each CPU */
398 	struct cfs_rq		**cfs_rq;
399 	unsigned long		shares;
400 
401 	/* A positive value indicates that this is a SCHED_IDLE group. */
402 	int			idle;
403 
404 #ifdef	CONFIG_SMP
405 	/*
406 	 * load_avg can be heavily contended at clock tick time, so put
407 	 * it in its own cacheline separated from the fields above which
408 	 * will also be accessed at each tick.
409 	 */
410 	atomic_long_t		load_avg ____cacheline_aligned;
411 #endif
412 #endif
413 
414 #ifdef CONFIG_RT_GROUP_SCHED
415 	struct sched_rt_entity	**rt_se;
416 	struct rt_rq		**rt_rq;
417 
418 	struct rt_bandwidth	rt_bandwidth;
419 #endif
420 
421 	struct rcu_head		rcu;
422 	struct list_head	list;
423 
424 	struct task_group	*parent;
425 	struct list_head	siblings;
426 	struct list_head	children;
427 
428 #ifdef CONFIG_SCHED_AUTOGROUP
429 	struct autogroup	*autogroup;
430 #endif
431 
432 	struct cfs_bandwidth	cfs_bandwidth;
433 
434 #ifdef CONFIG_UCLAMP_TASK_GROUP
435 	/* The two decimal precision [%] value requested from user-space */
436 	unsigned int		uclamp_pct[UCLAMP_CNT];
437 	/* Clamp values requested for a task group */
438 	struct uclamp_se	uclamp_req[UCLAMP_CNT];
439 	/* Effective clamp values used for a task group */
440 	struct uclamp_se	uclamp[UCLAMP_CNT];
441 #endif
442 
443 };
444 
445 #ifdef CONFIG_FAIR_GROUP_SCHED
446 #define ROOT_TASK_GROUP_LOAD	NICE_0_LOAD
447 
448 /*
449  * A weight of 0 or 1 can cause arithmetics problems.
450  * A weight of a cfs_rq is the sum of weights of which entities
451  * are queued on this cfs_rq, so a weight of a entity should not be
452  * too large, so as the shares value of a task group.
453  * (The default weight is 1024 - so there's no practical
454  *  limitation from this.)
455  */
456 #define MIN_SHARES		(1UL <<  1)
457 #define MAX_SHARES		(1UL << 18)
458 #endif
459 
460 typedef int (*tg_visitor)(struct task_group *, void *);
461 
462 extern int walk_tg_tree_from(struct task_group *from,
463 			     tg_visitor down, tg_visitor up, void *data);
464 
465 /*
466  * Iterate the full tree, calling @down when first entering a node and @up when
467  * leaving it for the final time.
468  *
469  * Caller must hold rcu_lock or sufficient equivalent.
470  */
walk_tg_tree(tg_visitor down,tg_visitor up,void * data)471 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
472 {
473 	return walk_tg_tree_from(&root_task_group, down, up, data);
474 }
475 
476 extern int tg_nop(struct task_group *tg, void *data);
477 
478 extern void free_fair_sched_group(struct task_group *tg);
479 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
480 extern void online_fair_sched_group(struct task_group *tg);
481 extern void unregister_fair_sched_group(struct task_group *tg);
482 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
483 			struct sched_entity *se, int cpu,
484 			struct sched_entity *parent);
485 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
486 
487 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
488 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
489 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
490 
491 extern void unregister_rt_sched_group(struct task_group *tg);
492 extern void free_rt_sched_group(struct task_group *tg);
493 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
494 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
495 		struct sched_rt_entity *rt_se, int cpu,
496 		struct sched_rt_entity *parent);
497 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
498 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
499 extern long sched_group_rt_runtime(struct task_group *tg);
500 extern long sched_group_rt_period(struct task_group *tg);
501 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
502 
503 extern struct task_group *sched_create_group(struct task_group *parent);
504 extern void sched_online_group(struct task_group *tg,
505 			       struct task_group *parent);
506 extern void sched_destroy_group(struct task_group *tg);
507 extern void sched_release_group(struct task_group *tg);
508 
509 extern void sched_move_task(struct task_struct *tsk);
510 
511 #ifdef CONFIG_FAIR_GROUP_SCHED
512 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
513 
514 extern int sched_group_set_idle(struct task_group *tg, long idle);
515 
516 #ifdef CONFIG_SMP
517 extern void set_task_rq_fair(struct sched_entity *se,
518 			     struct cfs_rq *prev, struct cfs_rq *next);
519 #else /* !CONFIG_SMP */
set_task_rq_fair(struct sched_entity * se,struct cfs_rq * prev,struct cfs_rq * next)520 static inline void set_task_rq_fair(struct sched_entity *se,
521 			     struct cfs_rq *prev, struct cfs_rq *next) { }
522 #endif /* CONFIG_SMP */
523 #endif /* CONFIG_FAIR_GROUP_SCHED */
524 
525 #else /* CONFIG_CGROUP_SCHED */
526 
527 struct cfs_bandwidth { };
528 
529 #endif	/* CONFIG_CGROUP_SCHED */
530 
531 /* CFS-related fields in a runqueue */
532 struct cfs_rq {
533 	struct load_weight	load;
534 	unsigned int		nr_running;
535 	unsigned int		h_nr_running;      /* SCHED_{NORMAL,BATCH,IDLE} */
536 	unsigned int		idle_nr_running;   /* SCHED_IDLE */
537 	unsigned int		idle_h_nr_running; /* SCHED_IDLE */
538 
539 	u64			exec_clock;
540 	u64			min_vruntime;
541 #ifdef CONFIG_SCHED_CORE
542 	unsigned int		forceidle_seq;
543 	u64			min_vruntime_fi;
544 #endif
545 
546 #ifndef CONFIG_64BIT
547 	u64			min_vruntime_copy;
548 #endif
549 
550 	struct rb_root_cached	tasks_timeline;
551 
552 	/*
553 	 * 'curr' points to currently running entity on this cfs_rq.
554 	 * It is set to NULL otherwise (i.e when none are currently running).
555 	 */
556 	struct sched_entity	*curr;
557 	struct sched_entity	*next;
558 	struct sched_entity	*last;
559 	struct sched_entity	*skip;
560 
561 #ifdef	CONFIG_SCHED_DEBUG
562 	unsigned int		nr_spread_over;
563 #endif
564 
565 #ifdef CONFIG_SMP
566 	/*
567 	 * CFS load tracking
568 	 */
569 	struct sched_avg	avg;
570 #ifndef CONFIG_64BIT
571 	u64			load_last_update_time_copy;
572 #endif
573 	struct {
574 		raw_spinlock_t	lock ____cacheline_aligned;
575 		int		nr;
576 		unsigned long	load_avg;
577 		unsigned long	util_avg;
578 		unsigned long	runnable_avg;
579 	} removed;
580 
581 #ifdef CONFIG_FAIR_GROUP_SCHED
582 	unsigned long		tg_load_avg_contrib;
583 	long			propagate;
584 	long			prop_runnable_sum;
585 
586 	/*
587 	 *   h_load = weight * f(tg)
588 	 *
589 	 * Where f(tg) is the recursive weight fraction assigned to
590 	 * this group.
591 	 */
592 	unsigned long		h_load;
593 	u64			last_h_load_update;
594 	struct sched_entity	*h_load_next;
595 #endif /* CONFIG_FAIR_GROUP_SCHED */
596 #endif /* CONFIG_SMP */
597 
598 #ifdef CONFIG_FAIR_GROUP_SCHED
599 	struct rq		*rq;	/* CPU runqueue to which this cfs_rq is attached */
600 
601 	/*
602 	 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
603 	 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
604 	 * (like users, containers etc.)
605 	 *
606 	 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
607 	 * This list is used during load balance.
608 	 */
609 	int			on_list;
610 	struct list_head	leaf_cfs_rq_list;
611 	struct task_group	*tg;	/* group that "owns" this runqueue */
612 
613 	/* Locally cached copy of our task_group's idle value */
614 	int			idle;
615 
616 #ifdef CONFIG_CFS_BANDWIDTH
617 	int			runtime_enabled;
618 	s64			runtime_remaining;
619 
620 	u64			throttled_clock;
621 	u64			throttled_clock_task;
622 	u64			throttled_clock_task_time;
623 	int			throttled;
624 	int			throttle_count;
625 	struct list_head	throttled_list;
626 #endif /* CONFIG_CFS_BANDWIDTH */
627 #endif /* CONFIG_FAIR_GROUP_SCHED */
628 };
629 
rt_bandwidth_enabled(void)630 static inline int rt_bandwidth_enabled(void)
631 {
632 	return sysctl_sched_rt_runtime >= 0;
633 }
634 
635 /* RT IPI pull logic requires IRQ_WORK */
636 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
637 # define HAVE_RT_PUSH_IPI
638 #endif
639 
640 /* Real-Time classes' related field in a runqueue: */
641 struct rt_rq {
642 	struct rt_prio_array	active;
643 	unsigned int		rt_nr_running;
644 	unsigned int		rr_nr_running;
645 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
646 	struct {
647 		int		curr; /* highest queued rt task prio */
648 #ifdef CONFIG_SMP
649 		int		next; /* next highest */
650 #endif
651 	} highest_prio;
652 #endif
653 #ifdef CONFIG_SMP
654 	unsigned int		rt_nr_migratory;
655 	unsigned int		rt_nr_total;
656 	int			overloaded;
657 	struct plist_head	pushable_tasks;
658 
659 #endif /* CONFIG_SMP */
660 	int			rt_queued;
661 
662 	int			rt_throttled;
663 	u64			rt_time;
664 	u64			rt_runtime;
665 	/* Nests inside the rq lock: */
666 	raw_spinlock_t		rt_runtime_lock;
667 
668 #ifdef CONFIG_RT_GROUP_SCHED
669 	unsigned int		rt_nr_boosted;
670 
671 	struct rq		*rq;
672 	struct task_group	*tg;
673 #endif
674 };
675 
rt_rq_is_runnable(struct rt_rq * rt_rq)676 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
677 {
678 	return rt_rq->rt_queued && rt_rq->rt_nr_running;
679 }
680 
681 /* Deadline class' related fields in a runqueue */
682 struct dl_rq {
683 	/* runqueue is an rbtree, ordered by deadline */
684 	struct rb_root_cached	root;
685 
686 	unsigned int		dl_nr_running;
687 
688 #ifdef CONFIG_SMP
689 	/*
690 	 * Deadline values of the currently executing and the
691 	 * earliest ready task on this rq. Caching these facilitates
692 	 * the decision whether or not a ready but not running task
693 	 * should migrate somewhere else.
694 	 */
695 	struct {
696 		u64		curr;
697 		u64		next;
698 	} earliest_dl;
699 
700 	unsigned int		dl_nr_migratory;
701 	int			overloaded;
702 
703 	/*
704 	 * Tasks on this rq that can be pushed away. They are kept in
705 	 * an rb-tree, ordered by tasks' deadlines, with caching
706 	 * of the leftmost (earliest deadline) element.
707 	 */
708 	struct rb_root_cached	pushable_dl_tasks_root;
709 #else
710 	struct dl_bw		dl_bw;
711 #endif
712 	/*
713 	 * "Active utilization" for this runqueue: increased when a
714 	 * task wakes up (becomes TASK_RUNNING) and decreased when a
715 	 * task blocks
716 	 */
717 	u64			running_bw;
718 
719 	/*
720 	 * Utilization of the tasks "assigned" to this runqueue (including
721 	 * the tasks that are in runqueue and the tasks that executed on this
722 	 * CPU and blocked). Increased when a task moves to this runqueue, and
723 	 * decreased when the task moves away (migrates, changes scheduling
724 	 * policy, or terminates).
725 	 * This is needed to compute the "inactive utilization" for the
726 	 * runqueue (inactive utilization = this_bw - running_bw).
727 	 */
728 	u64			this_bw;
729 	u64			extra_bw;
730 
731 	/*
732 	 * Inverse of the fraction of CPU utilization that can be reclaimed
733 	 * by the GRUB algorithm.
734 	 */
735 	u64			bw_ratio;
736 };
737 
738 #ifdef CONFIG_FAIR_GROUP_SCHED
739 /* An entity is a task if it doesn't "own" a runqueue */
740 #define entity_is_task(se)	(!se->my_q)
741 
se_update_runnable(struct sched_entity * se)742 static inline void se_update_runnable(struct sched_entity *se)
743 {
744 	if (!entity_is_task(se))
745 		se->runnable_weight = se->my_q->h_nr_running;
746 }
747 
se_runnable(struct sched_entity * se)748 static inline long se_runnable(struct sched_entity *se)
749 {
750 	if (entity_is_task(se))
751 		return !!se->on_rq;
752 	else
753 		return se->runnable_weight;
754 }
755 
756 #else
757 #define entity_is_task(se)	1
758 
se_update_runnable(struct sched_entity * se)759 static inline void se_update_runnable(struct sched_entity *se) {}
760 
se_runnable(struct sched_entity * se)761 static inline long se_runnable(struct sched_entity *se)
762 {
763 	return !!se->on_rq;
764 }
765 #endif
766 
767 #ifdef CONFIG_SMP
768 /*
769  * XXX we want to get rid of these helpers and use the full load resolution.
770  */
se_weight(struct sched_entity * se)771 static inline long se_weight(struct sched_entity *se)
772 {
773 	return scale_load_down(se->load.weight);
774 }
775 
776 
sched_asym_prefer(int a,int b)777 static inline bool sched_asym_prefer(int a, int b)
778 {
779 	return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
780 }
781 
782 struct perf_domain {
783 	struct em_perf_domain *em_pd;
784 	struct perf_domain *next;
785 	struct rcu_head rcu;
786 };
787 
788 /* Scheduling group status flags */
789 #define SG_OVERLOAD		0x1 /* More than one runnable task on a CPU. */
790 #define SG_OVERUTILIZED		0x2 /* One or more CPUs are over-utilized. */
791 
792 /*
793  * We add the notion of a root-domain which will be used to define per-domain
794  * variables. Each exclusive cpuset essentially defines an island domain by
795  * fully partitioning the member CPUs from any other cpuset. Whenever a new
796  * exclusive cpuset is created, we also create and attach a new root-domain
797  * object.
798  *
799  */
800 struct root_domain {
801 	atomic_t		refcount;
802 	atomic_t		rto_count;
803 	struct rcu_head		rcu;
804 	cpumask_var_t		span;
805 	cpumask_var_t		online;
806 
807 	/*
808 	 * Indicate pullable load on at least one CPU, e.g:
809 	 * - More than one runnable task
810 	 * - Running task is misfit
811 	 */
812 	int			overload;
813 
814 	/* Indicate one or more cpus over-utilized (tipping point) */
815 	int			overutilized;
816 
817 	/*
818 	 * The bit corresponding to a CPU gets set here if such CPU has more
819 	 * than one runnable -deadline task (as it is below for RT tasks).
820 	 */
821 	cpumask_var_t		dlo_mask;
822 	atomic_t		dlo_count;
823 	struct dl_bw		dl_bw;
824 	struct cpudl		cpudl;
825 
826 	/*
827 	 * Indicate whether a root_domain's dl_bw has been checked or
828 	 * updated. It's monotonously increasing value.
829 	 *
830 	 * Also, some corner cases, like 'wrap around' is dangerous, but given
831 	 * that u64 is 'big enough'. So that shouldn't be a concern.
832 	 */
833 	u64 visit_gen;
834 
835 #ifdef HAVE_RT_PUSH_IPI
836 	/*
837 	 * For IPI pull requests, loop across the rto_mask.
838 	 */
839 	struct irq_work		rto_push_work;
840 	raw_spinlock_t		rto_lock;
841 	/* These are only updated and read within rto_lock */
842 	int			rto_loop;
843 	int			rto_cpu;
844 	/* These atomics are updated outside of a lock */
845 	atomic_t		rto_loop_next;
846 	atomic_t		rto_loop_start;
847 #endif
848 	/*
849 	 * The "RT overload" flag: it gets set if a CPU has more than
850 	 * one runnable RT task.
851 	 */
852 	cpumask_var_t		rto_mask;
853 	struct cpupri		cpupri;
854 
855 	unsigned long		max_cpu_capacity;
856 
857 	/*
858 	 * NULL-terminated list of performance domains intersecting with the
859 	 * CPUs of the rd. Protected by RCU.
860 	 */
861 	struct perf_domain __rcu *pd;
862 };
863 
864 extern void init_defrootdomain(void);
865 extern int sched_init_domains(const struct cpumask *cpu_map);
866 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
867 extern void sched_get_rd(struct root_domain *rd);
868 extern void sched_put_rd(struct root_domain *rd);
869 
870 #ifdef HAVE_RT_PUSH_IPI
871 extern void rto_push_irq_work_func(struct irq_work *work);
872 #endif
873 #endif /* CONFIG_SMP */
874 
875 #ifdef CONFIG_UCLAMP_TASK
876 /*
877  * struct uclamp_bucket - Utilization clamp bucket
878  * @value: utilization clamp value for tasks on this clamp bucket
879  * @tasks: number of RUNNABLE tasks on this clamp bucket
880  *
881  * Keep track of how many tasks are RUNNABLE for a given utilization
882  * clamp value.
883  */
884 struct uclamp_bucket {
885 	unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
886 	unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
887 };
888 
889 /*
890  * struct uclamp_rq - rq's utilization clamp
891  * @value: currently active clamp values for a rq
892  * @bucket: utilization clamp buckets affecting a rq
893  *
894  * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
895  * A clamp value is affecting a rq when there is at least one task RUNNABLE
896  * (or actually running) with that value.
897  *
898  * There are up to UCLAMP_CNT possible different clamp values, currently there
899  * are only two: minimum utilization and maximum utilization.
900  *
901  * All utilization clamping values are MAX aggregated, since:
902  * - for util_min: we want to run the CPU at least at the max of the minimum
903  *   utilization required by its currently RUNNABLE tasks.
904  * - for util_max: we want to allow the CPU to run up to the max of the
905  *   maximum utilization allowed by its currently RUNNABLE tasks.
906  *
907  * Since on each system we expect only a limited number of different
908  * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
909  * the metrics required to compute all the per-rq utilization clamp values.
910  */
911 struct uclamp_rq {
912 	unsigned int value;
913 	struct uclamp_bucket bucket[UCLAMP_BUCKETS];
914 };
915 
916 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
917 #endif /* CONFIG_UCLAMP_TASK */
918 
919 /*
920  * This is the main, per-CPU runqueue data structure.
921  *
922  * Locking rule: those places that want to lock multiple runqueues
923  * (such as the load balancing or the thread migration code), lock
924  * acquire operations must be ordered by ascending &runqueue.
925  */
926 struct rq {
927 	/* runqueue lock: */
928 	raw_spinlock_t		__lock;
929 
930 	/*
931 	 * nr_running and cpu_load should be in the same cacheline because
932 	 * remote CPUs use both these fields when doing load calculation.
933 	 */
934 	unsigned int		nr_running;
935 #ifdef CONFIG_NUMA_BALANCING
936 	unsigned int		nr_numa_running;
937 	unsigned int		nr_preferred_running;
938 	unsigned int		numa_migrate_on;
939 #endif
940 #ifdef CONFIG_NO_HZ_COMMON
941 #ifdef CONFIG_SMP
942 	unsigned long		last_blocked_load_update_tick;
943 	unsigned int		has_blocked_load;
944 	call_single_data_t	nohz_csd;
945 #endif /* CONFIG_SMP */
946 	unsigned int		nohz_tick_stopped;
947 	atomic_t		nohz_flags;
948 #endif /* CONFIG_NO_HZ_COMMON */
949 
950 #ifdef CONFIG_SMP
951 	unsigned int		ttwu_pending;
952 #endif
953 	u64			nr_switches;
954 
955 #ifdef CONFIG_UCLAMP_TASK
956 	/* Utilization clamp values based on CPU's RUNNABLE tasks */
957 	struct uclamp_rq	uclamp[UCLAMP_CNT] ____cacheline_aligned;
958 	unsigned int		uclamp_flags;
959 #define UCLAMP_FLAG_IDLE 0x01
960 #endif
961 
962 	struct cfs_rq		cfs;
963 	struct rt_rq		rt;
964 	struct dl_rq		dl;
965 
966 #ifdef CONFIG_FAIR_GROUP_SCHED
967 	/* list of leaf cfs_rq on this CPU: */
968 	struct list_head	leaf_cfs_rq_list;
969 	struct list_head	*tmp_alone_branch;
970 #endif /* CONFIG_FAIR_GROUP_SCHED */
971 
972 	/*
973 	 * This is part of a global counter where only the total sum
974 	 * over all CPUs matters. A task can increase this counter on
975 	 * one CPU and if it got migrated afterwards it may decrease
976 	 * it on another CPU. Always updated under the runqueue lock:
977 	 */
978 	unsigned int		nr_uninterruptible;
979 
980 	struct task_struct __rcu	*curr;
981 	struct task_struct	*idle;
982 	struct task_struct	*stop;
983 	unsigned long		next_balance;
984 	struct mm_struct	*prev_mm;
985 
986 	unsigned int		clock_update_flags;
987 	u64			clock;
988 	/* Ensure that all clocks are in the same cache line */
989 	u64			clock_task ____cacheline_aligned;
990 	u64			clock_pelt;
991 	unsigned long		lost_idle_time;
992 
993 	atomic_t		nr_iowait;
994 
995 #ifdef CONFIG_SCHED_DEBUG
996 	u64 last_seen_need_resched_ns;
997 	int ticks_without_resched;
998 #endif
999 
1000 #ifdef CONFIG_MEMBARRIER
1001 	int membarrier_state;
1002 #endif
1003 
1004 #ifdef CONFIG_SMP
1005 	struct root_domain		*rd;
1006 	struct sched_domain __rcu	*sd;
1007 
1008 	unsigned long		cpu_capacity;
1009 	unsigned long		cpu_capacity_orig;
1010 
1011 	struct callback_head	*balance_callback;
1012 
1013 	unsigned char		nohz_idle_balance;
1014 	unsigned char		idle_balance;
1015 
1016 	unsigned long		misfit_task_load;
1017 
1018 	/* For active balancing */
1019 	int			active_balance;
1020 	int			push_cpu;
1021 	struct cpu_stop_work	active_balance_work;
1022 
1023 	/* CPU of this runqueue: */
1024 	int			cpu;
1025 	int			online;
1026 
1027 	struct list_head cfs_tasks;
1028 
1029 	struct sched_avg	avg_rt;
1030 	struct sched_avg	avg_dl;
1031 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1032 	struct sched_avg	avg_irq;
1033 #endif
1034 #ifdef CONFIG_SCHED_THERMAL_PRESSURE
1035 	struct sched_avg	avg_thermal;
1036 #endif
1037 	u64			idle_stamp;
1038 	u64			avg_idle;
1039 
1040 	unsigned long		wake_stamp;
1041 	u64			wake_avg_idle;
1042 
1043 	/* This is used to determine avg_idle's max value */
1044 	u64			max_idle_balance_cost;
1045 
1046 #ifdef CONFIG_HOTPLUG_CPU
1047 	struct rcuwait		hotplug_wait;
1048 #endif
1049 #endif /* CONFIG_SMP */
1050 
1051 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1052 	u64			prev_irq_time;
1053 #endif
1054 #ifdef CONFIG_PARAVIRT
1055 	u64			prev_steal_time;
1056 #endif
1057 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1058 	u64			prev_steal_time_rq;
1059 #endif
1060 
1061 	/* calc_load related fields */
1062 	unsigned long		calc_load_update;
1063 	long			calc_load_active;
1064 
1065 #ifdef CONFIG_SCHED_HRTICK
1066 #ifdef CONFIG_SMP
1067 	call_single_data_t	hrtick_csd;
1068 #endif
1069 	struct hrtimer		hrtick_timer;
1070 	ktime_t 		hrtick_time;
1071 #endif
1072 
1073 #ifdef CONFIG_SCHEDSTATS
1074 	/* latency stats */
1075 	struct sched_info	rq_sched_info;
1076 	unsigned long long	rq_cpu_time;
1077 	/* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
1078 
1079 	/* sys_sched_yield() stats */
1080 	unsigned int		yld_count;
1081 
1082 	/* schedule() stats */
1083 	unsigned int		sched_count;
1084 	unsigned int		sched_goidle;
1085 
1086 	/* try_to_wake_up() stats */
1087 	unsigned int		ttwu_count;
1088 	unsigned int		ttwu_local;
1089 #endif
1090 
1091 #ifdef CONFIG_CPU_IDLE
1092 	/* Must be inspected within a rcu lock section */
1093 	struct cpuidle_state	*idle_state;
1094 #endif
1095 
1096 #ifdef CONFIG_SMP
1097 	unsigned int		nr_pinned;
1098 #endif
1099 	unsigned int		push_busy;
1100 	struct cpu_stop_work	push_work;
1101 
1102 #ifdef CONFIG_SCHED_CORE
1103 	/* per rq */
1104 	struct rq		*core;
1105 	struct task_struct	*core_pick;
1106 	unsigned int		core_enabled;
1107 	unsigned int		core_sched_seq;
1108 	struct rb_root		core_tree;
1109 
1110 	/* shared state -- careful with sched_core_cpu_deactivate() */
1111 	unsigned int		core_task_seq;
1112 	unsigned int		core_pick_seq;
1113 	unsigned long		core_cookie;
1114 	unsigned char		core_forceidle;
1115 	unsigned int		core_forceidle_seq;
1116 #endif
1117 };
1118 
1119 #ifdef CONFIG_FAIR_GROUP_SCHED
1120 
1121 /* CPU runqueue to which this cfs_rq is attached */
rq_of(struct cfs_rq * cfs_rq)1122 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1123 {
1124 	return cfs_rq->rq;
1125 }
1126 
1127 #else
1128 
rq_of(struct cfs_rq * cfs_rq)1129 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1130 {
1131 	return container_of(cfs_rq, struct rq, cfs);
1132 }
1133 #endif
1134 
cpu_of(struct rq * rq)1135 static inline int cpu_of(struct rq *rq)
1136 {
1137 #ifdef CONFIG_SMP
1138 	return rq->cpu;
1139 #else
1140 	return 0;
1141 #endif
1142 }
1143 
1144 #define MDF_PUSH	0x01
1145 
is_migration_disabled(struct task_struct * p)1146 static inline bool is_migration_disabled(struct task_struct *p)
1147 {
1148 #ifdef CONFIG_SMP
1149 	return p->migration_disabled;
1150 #else
1151 	return false;
1152 #endif
1153 }
1154 
1155 struct sched_group;
1156 #ifdef CONFIG_SCHED_CORE
1157 static inline struct cpumask *sched_group_span(struct sched_group *sg);
1158 
1159 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled);
1160 
sched_core_enabled(struct rq * rq)1161 static inline bool sched_core_enabled(struct rq *rq)
1162 {
1163 	return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled;
1164 }
1165 
sched_core_disabled(void)1166 static inline bool sched_core_disabled(void)
1167 {
1168 	return !static_branch_unlikely(&__sched_core_enabled);
1169 }
1170 
1171 /*
1172  * Be careful with this function; not for general use. The return value isn't
1173  * stable unless you actually hold a relevant rq->__lock.
1174  */
rq_lockp(struct rq * rq)1175 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1176 {
1177 	if (sched_core_enabled(rq))
1178 		return &rq->core->__lock;
1179 
1180 	return &rq->__lock;
1181 }
1182 
__rq_lockp(struct rq * rq)1183 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1184 {
1185 	if (rq->core_enabled)
1186 		return &rq->core->__lock;
1187 
1188 	return &rq->__lock;
1189 }
1190 
1191 bool cfs_prio_less(struct task_struct *a, struct task_struct *b, bool fi);
1192 
1193 /*
1194  * Helpers to check if the CPU's core cookie matches with the task's cookie
1195  * when core scheduling is enabled.
1196  * A special case is that the task's cookie always matches with CPU's core
1197  * cookie if the CPU is in an idle core.
1198  */
sched_cpu_cookie_match(struct rq * rq,struct task_struct * p)1199 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1200 {
1201 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1202 	if (!sched_core_enabled(rq))
1203 		return true;
1204 
1205 	return rq->core->core_cookie == p->core_cookie;
1206 }
1207 
sched_core_cookie_match(struct rq * rq,struct task_struct * p)1208 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1209 {
1210 	bool idle_core = true;
1211 	int cpu;
1212 
1213 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1214 	if (!sched_core_enabled(rq))
1215 		return true;
1216 
1217 	for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) {
1218 		if (!available_idle_cpu(cpu)) {
1219 			idle_core = false;
1220 			break;
1221 		}
1222 	}
1223 
1224 	/*
1225 	 * A CPU in an idle core is always the best choice for tasks with
1226 	 * cookies.
1227 	 */
1228 	return idle_core || rq->core->core_cookie == p->core_cookie;
1229 }
1230 
sched_group_cookie_match(struct rq * rq,struct task_struct * p,struct sched_group * group)1231 static inline bool sched_group_cookie_match(struct rq *rq,
1232 					    struct task_struct *p,
1233 					    struct sched_group *group)
1234 {
1235 	int cpu;
1236 
1237 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1238 	if (!sched_core_enabled(rq))
1239 		return true;
1240 
1241 	for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
1242 		if (sched_core_cookie_match(rq, p))
1243 			return true;
1244 	}
1245 	return false;
1246 }
1247 
1248 extern void queue_core_balance(struct rq *rq);
1249 
sched_core_enqueued(struct task_struct * p)1250 static inline bool sched_core_enqueued(struct task_struct *p)
1251 {
1252 	return !RB_EMPTY_NODE(&p->core_node);
1253 }
1254 
1255 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p);
1256 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p);
1257 
1258 extern void sched_core_get(void);
1259 extern void sched_core_put(void);
1260 
1261 #else /* !CONFIG_SCHED_CORE */
1262 
sched_core_enabled(struct rq * rq)1263 static inline bool sched_core_enabled(struct rq *rq)
1264 {
1265 	return false;
1266 }
1267 
sched_core_disabled(void)1268 static inline bool sched_core_disabled(void)
1269 {
1270 	return true;
1271 }
1272 
rq_lockp(struct rq * rq)1273 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1274 {
1275 	return &rq->__lock;
1276 }
1277 
__rq_lockp(struct rq * rq)1278 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1279 {
1280 	return &rq->__lock;
1281 }
1282 
queue_core_balance(struct rq * rq)1283 static inline void queue_core_balance(struct rq *rq)
1284 {
1285 }
1286 
sched_cpu_cookie_match(struct rq * rq,struct task_struct * p)1287 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1288 {
1289 	return true;
1290 }
1291 
sched_core_cookie_match(struct rq * rq,struct task_struct * p)1292 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1293 {
1294 	return true;
1295 }
1296 
sched_group_cookie_match(struct rq * rq,struct task_struct * p,struct sched_group * group)1297 static inline bool sched_group_cookie_match(struct rq *rq,
1298 					    struct task_struct *p,
1299 					    struct sched_group *group)
1300 {
1301 	return true;
1302 }
1303 #endif /* CONFIG_SCHED_CORE */
1304 
lockdep_assert_rq_held(struct rq * rq)1305 static inline void lockdep_assert_rq_held(struct rq *rq)
1306 {
1307 	lockdep_assert_held(__rq_lockp(rq));
1308 }
1309 
1310 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass);
1311 extern bool raw_spin_rq_trylock(struct rq *rq);
1312 extern void raw_spin_rq_unlock(struct rq *rq);
1313 
raw_spin_rq_lock(struct rq * rq)1314 static inline void raw_spin_rq_lock(struct rq *rq)
1315 {
1316 	raw_spin_rq_lock_nested(rq, 0);
1317 }
1318 
raw_spin_rq_lock_irq(struct rq * rq)1319 static inline void raw_spin_rq_lock_irq(struct rq *rq)
1320 {
1321 	local_irq_disable();
1322 	raw_spin_rq_lock(rq);
1323 }
1324 
raw_spin_rq_unlock_irq(struct rq * rq)1325 static inline void raw_spin_rq_unlock_irq(struct rq *rq)
1326 {
1327 	raw_spin_rq_unlock(rq);
1328 	local_irq_enable();
1329 }
1330 
_raw_spin_rq_lock_irqsave(struct rq * rq)1331 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq)
1332 {
1333 	unsigned long flags;
1334 	local_irq_save(flags);
1335 	raw_spin_rq_lock(rq);
1336 	return flags;
1337 }
1338 
raw_spin_rq_unlock_irqrestore(struct rq * rq,unsigned long flags)1339 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags)
1340 {
1341 	raw_spin_rq_unlock(rq);
1342 	local_irq_restore(flags);
1343 }
1344 
1345 #define raw_spin_rq_lock_irqsave(rq, flags)	\
1346 do {						\
1347 	flags = _raw_spin_rq_lock_irqsave(rq);	\
1348 } while (0)
1349 
1350 #ifdef CONFIG_SCHED_SMT
1351 extern void __update_idle_core(struct rq *rq);
1352 
update_idle_core(struct rq * rq)1353 static inline void update_idle_core(struct rq *rq)
1354 {
1355 	if (static_branch_unlikely(&sched_smt_present))
1356 		__update_idle_core(rq);
1357 }
1358 
1359 #else
update_idle_core(struct rq * rq)1360 static inline void update_idle_core(struct rq *rq) { }
1361 #endif
1362 
1363 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1364 
1365 #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
1366 #define this_rq()		this_cpu_ptr(&runqueues)
1367 #define task_rq(p)		cpu_rq(task_cpu(p))
1368 #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
1369 #define raw_rq()		raw_cpu_ptr(&runqueues)
1370 
1371 #ifdef CONFIG_FAIR_GROUP_SCHED
task_of(struct sched_entity * se)1372 static inline struct task_struct *task_of(struct sched_entity *se)
1373 {
1374 	SCHED_WARN_ON(!entity_is_task(se));
1375 	return container_of(se, struct task_struct, se);
1376 }
1377 
task_cfs_rq(struct task_struct * p)1378 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1379 {
1380 	return p->se.cfs_rq;
1381 }
1382 
1383 /* runqueue on which this entity is (to be) queued */
cfs_rq_of(struct sched_entity * se)1384 static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se)
1385 {
1386 	return se->cfs_rq;
1387 }
1388 
1389 /* runqueue "owned" by this group */
group_cfs_rq(struct sched_entity * grp)1390 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1391 {
1392 	return grp->my_q;
1393 }
1394 
1395 #else
1396 
task_of(struct sched_entity * se)1397 static inline struct task_struct *task_of(struct sched_entity *se)
1398 {
1399 	return container_of(se, struct task_struct, se);
1400 }
1401 
task_cfs_rq(struct task_struct * p)1402 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1403 {
1404 	return &task_rq(p)->cfs;
1405 }
1406 
cfs_rq_of(struct sched_entity * se)1407 static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se)
1408 {
1409 	struct task_struct *p = task_of(se);
1410 	struct rq *rq = task_rq(p);
1411 
1412 	return &rq->cfs;
1413 }
1414 
1415 /* runqueue "owned" by this group */
group_cfs_rq(struct sched_entity * grp)1416 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1417 {
1418 	return NULL;
1419 }
1420 #endif
1421 
1422 extern void update_rq_clock(struct rq *rq);
1423 
1424 /*
1425  * rq::clock_update_flags bits
1426  *
1427  * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1428  *  call to __schedule(). This is an optimisation to avoid
1429  *  neighbouring rq clock updates.
1430  *
1431  * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1432  *  in effect and calls to update_rq_clock() are being ignored.
1433  *
1434  * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1435  *  made to update_rq_clock() since the last time rq::lock was pinned.
1436  *
1437  * If inside of __schedule(), clock_update_flags will have been
1438  * shifted left (a left shift is a cheap operation for the fast path
1439  * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1440  *
1441  *	if (rq-clock_update_flags >= RQCF_UPDATED)
1442  *
1443  * to check if %RQCF_UPDATED is set. It'll never be shifted more than
1444  * one position though, because the next rq_unpin_lock() will shift it
1445  * back.
1446  */
1447 #define RQCF_REQ_SKIP		0x01
1448 #define RQCF_ACT_SKIP		0x02
1449 #define RQCF_UPDATED		0x04
1450 
assert_clock_updated(struct rq * rq)1451 static inline void assert_clock_updated(struct rq *rq)
1452 {
1453 	/*
1454 	 * The only reason for not seeing a clock update since the
1455 	 * last rq_pin_lock() is if we're currently skipping updates.
1456 	 */
1457 	SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
1458 }
1459 
rq_clock(struct rq * rq)1460 static inline u64 rq_clock(struct rq *rq)
1461 {
1462 	lockdep_assert_rq_held(rq);
1463 	assert_clock_updated(rq);
1464 
1465 	return rq->clock;
1466 }
1467 
rq_clock_task(struct rq * rq)1468 static inline u64 rq_clock_task(struct rq *rq)
1469 {
1470 	lockdep_assert_rq_held(rq);
1471 	assert_clock_updated(rq);
1472 
1473 	return rq->clock_task;
1474 }
1475 
1476 /**
1477  * By default the decay is the default pelt decay period.
1478  * The decay shift can change the decay period in
1479  * multiples of 32.
1480  *  Decay shift		Decay period(ms)
1481  *	0			32
1482  *	1			64
1483  *	2			128
1484  *	3			256
1485  *	4			512
1486  */
1487 extern int sched_thermal_decay_shift;
1488 
rq_clock_thermal(struct rq * rq)1489 static inline u64 rq_clock_thermal(struct rq *rq)
1490 {
1491 	return rq_clock_task(rq) >> sched_thermal_decay_shift;
1492 }
1493 
rq_clock_skip_update(struct rq * rq)1494 static inline void rq_clock_skip_update(struct rq *rq)
1495 {
1496 	lockdep_assert_rq_held(rq);
1497 	rq->clock_update_flags |= RQCF_REQ_SKIP;
1498 }
1499 
1500 /*
1501  * See rt task throttling, which is the only time a skip
1502  * request is canceled.
1503  */
rq_clock_cancel_skipupdate(struct rq * rq)1504 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1505 {
1506 	lockdep_assert_rq_held(rq);
1507 	rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1508 }
1509 
1510 struct rq_flags {
1511 	unsigned long flags;
1512 	struct pin_cookie cookie;
1513 #ifdef CONFIG_SCHED_DEBUG
1514 	/*
1515 	 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1516 	 * current pin context is stashed here in case it needs to be
1517 	 * restored in rq_repin_lock().
1518 	 */
1519 	unsigned int clock_update_flags;
1520 #endif
1521 };
1522 
1523 extern struct callback_head balance_push_callback;
1524 
1525 /*
1526  * Lockdep annotation that avoids accidental unlocks; it's like a
1527  * sticky/continuous lockdep_assert_held().
1528  *
1529  * This avoids code that has access to 'struct rq *rq' (basically everything in
1530  * the scheduler) from accidentally unlocking the rq if they do not also have a
1531  * copy of the (on-stack) 'struct rq_flags rf'.
1532  *
1533  * Also see Documentation/locking/lockdep-design.rst.
1534  */
rq_pin_lock(struct rq * rq,struct rq_flags * rf)1535 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1536 {
1537 	rf->cookie = lockdep_pin_lock(__rq_lockp(rq));
1538 
1539 #ifdef CONFIG_SCHED_DEBUG
1540 	rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1541 	rf->clock_update_flags = 0;
1542 #ifdef CONFIG_SMP
1543 	SCHED_WARN_ON(rq->balance_callback && rq->balance_callback != &balance_push_callback);
1544 #endif
1545 #endif
1546 }
1547 
rq_unpin_lock(struct rq * rq,struct rq_flags * rf)1548 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1549 {
1550 #ifdef CONFIG_SCHED_DEBUG
1551 	if (rq->clock_update_flags > RQCF_ACT_SKIP)
1552 		rf->clock_update_flags = RQCF_UPDATED;
1553 #endif
1554 
1555 	lockdep_unpin_lock(__rq_lockp(rq), rf->cookie);
1556 }
1557 
rq_repin_lock(struct rq * rq,struct rq_flags * rf)1558 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1559 {
1560 	lockdep_repin_lock(__rq_lockp(rq), rf->cookie);
1561 
1562 #ifdef CONFIG_SCHED_DEBUG
1563 	/*
1564 	 * Restore the value we stashed in @rf for this pin context.
1565 	 */
1566 	rq->clock_update_flags |= rf->clock_update_flags;
1567 #endif
1568 }
1569 
1570 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1571 	__acquires(rq->lock);
1572 
1573 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1574 	__acquires(p->pi_lock)
1575 	__acquires(rq->lock);
1576 
__task_rq_unlock(struct rq * rq,struct rq_flags * rf)1577 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1578 	__releases(rq->lock)
1579 {
1580 	rq_unpin_lock(rq, rf);
1581 	raw_spin_rq_unlock(rq);
1582 }
1583 
1584 static inline void
task_rq_unlock(struct rq * rq,struct task_struct * p,struct rq_flags * rf)1585 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1586 	__releases(rq->lock)
1587 	__releases(p->pi_lock)
1588 {
1589 	rq_unpin_lock(rq, rf);
1590 	raw_spin_rq_unlock(rq);
1591 	raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1592 }
1593 
1594 static inline void
rq_lock_irqsave(struct rq * rq,struct rq_flags * rf)1595 rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1596 	__acquires(rq->lock)
1597 {
1598 	raw_spin_rq_lock_irqsave(rq, rf->flags);
1599 	rq_pin_lock(rq, rf);
1600 }
1601 
1602 static inline void
rq_lock_irq(struct rq * rq,struct rq_flags * rf)1603 rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1604 	__acquires(rq->lock)
1605 {
1606 	raw_spin_rq_lock_irq(rq);
1607 	rq_pin_lock(rq, rf);
1608 }
1609 
1610 static inline void
rq_lock(struct rq * rq,struct rq_flags * rf)1611 rq_lock(struct rq *rq, struct rq_flags *rf)
1612 	__acquires(rq->lock)
1613 {
1614 	raw_spin_rq_lock(rq);
1615 	rq_pin_lock(rq, rf);
1616 }
1617 
1618 static inline void
rq_unlock_irqrestore(struct rq * rq,struct rq_flags * rf)1619 rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1620 	__releases(rq->lock)
1621 {
1622 	rq_unpin_lock(rq, rf);
1623 	raw_spin_rq_unlock_irqrestore(rq, rf->flags);
1624 }
1625 
1626 static inline void
rq_unlock_irq(struct rq * rq,struct rq_flags * rf)1627 rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1628 	__releases(rq->lock)
1629 {
1630 	rq_unpin_lock(rq, rf);
1631 	raw_spin_rq_unlock_irq(rq);
1632 }
1633 
1634 static inline void
rq_unlock(struct rq * rq,struct rq_flags * rf)1635 rq_unlock(struct rq *rq, struct rq_flags *rf)
1636 	__releases(rq->lock)
1637 {
1638 	rq_unpin_lock(rq, rf);
1639 	raw_spin_rq_unlock(rq);
1640 }
1641 
1642 static inline struct rq *
this_rq_lock_irq(struct rq_flags * rf)1643 this_rq_lock_irq(struct rq_flags *rf)
1644 	__acquires(rq->lock)
1645 {
1646 	struct rq *rq;
1647 
1648 	local_irq_disable();
1649 	rq = this_rq();
1650 	rq_lock(rq, rf);
1651 	return rq;
1652 }
1653 
1654 #ifdef CONFIG_NUMA
1655 enum numa_topology_type {
1656 	NUMA_DIRECT,
1657 	NUMA_GLUELESS_MESH,
1658 	NUMA_BACKPLANE,
1659 };
1660 extern enum numa_topology_type sched_numa_topology_type;
1661 extern int sched_max_numa_distance;
1662 extern bool find_numa_distance(int distance);
1663 extern void sched_init_numa(void);
1664 extern void sched_domains_numa_masks_set(unsigned int cpu);
1665 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1666 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1667 #else
sched_init_numa(void)1668 static inline void sched_init_numa(void) { }
sched_domains_numa_masks_set(unsigned int cpu)1669 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
sched_domains_numa_masks_clear(unsigned int cpu)1670 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
sched_numa_find_closest(const struct cpumask * cpus,int cpu)1671 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1672 {
1673 	return nr_cpu_ids;
1674 }
1675 #endif
1676 
1677 #ifdef CONFIG_NUMA_BALANCING
1678 /* The regions in numa_faults array from task_struct */
1679 enum numa_faults_stats {
1680 	NUMA_MEM = 0,
1681 	NUMA_CPU,
1682 	NUMA_MEMBUF,
1683 	NUMA_CPUBUF
1684 };
1685 extern void sched_setnuma(struct task_struct *p, int node);
1686 extern int migrate_task_to(struct task_struct *p, int cpu);
1687 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1688 			int cpu, int scpu);
1689 extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1690 #else
1691 static inline void
init_numa_balancing(unsigned long clone_flags,struct task_struct * p)1692 init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1693 {
1694 }
1695 #endif /* CONFIG_NUMA_BALANCING */
1696 
1697 #ifdef CONFIG_SMP
1698 
1699 static inline void
queue_balance_callback(struct rq * rq,struct callback_head * head,void (* func)(struct rq * rq))1700 queue_balance_callback(struct rq *rq,
1701 		       struct callback_head *head,
1702 		       void (*func)(struct rq *rq))
1703 {
1704 	lockdep_assert_rq_held(rq);
1705 
1706 	if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
1707 		return;
1708 
1709 	head->func = (void (*)(struct callback_head *))func;
1710 	head->next = rq->balance_callback;
1711 	rq->balance_callback = head;
1712 }
1713 
1714 #define rcu_dereference_check_sched_domain(p) \
1715 	rcu_dereference_check((p), \
1716 			      lockdep_is_held(&sched_domains_mutex))
1717 
1718 /*
1719  * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1720  * See destroy_sched_domains: call_rcu for details.
1721  *
1722  * The domain tree of any CPU may only be accessed from within
1723  * preempt-disabled sections.
1724  */
1725 #define for_each_domain(cpu, __sd) \
1726 	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1727 			__sd; __sd = __sd->parent)
1728 
1729 /**
1730  * highest_flag_domain - Return highest sched_domain containing flag.
1731  * @cpu:	The CPU whose highest level of sched domain is to
1732  *		be returned.
1733  * @flag:	The flag to check for the highest sched_domain
1734  *		for the given CPU.
1735  *
1736  * Returns the highest sched_domain of a CPU which contains the given flag.
1737  */
highest_flag_domain(int cpu,int flag)1738 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1739 {
1740 	struct sched_domain *sd, *hsd = NULL;
1741 
1742 	for_each_domain(cpu, sd) {
1743 		if (!(sd->flags & flag))
1744 			break;
1745 		hsd = sd;
1746 	}
1747 
1748 	return hsd;
1749 }
1750 
lowest_flag_domain(int cpu,int flag)1751 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1752 {
1753 	struct sched_domain *sd;
1754 
1755 	for_each_domain(cpu, sd) {
1756 		if (sd->flags & flag)
1757 			break;
1758 	}
1759 
1760 	return sd;
1761 }
1762 
1763 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
1764 DECLARE_PER_CPU(int, sd_llc_size);
1765 DECLARE_PER_CPU(int, sd_llc_id);
1766 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
1767 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
1768 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
1769 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
1770 extern struct static_key_false sched_asym_cpucapacity;
1771 
1772 struct sched_group_capacity {
1773 	atomic_t		ref;
1774 	/*
1775 	 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
1776 	 * for a single CPU.
1777 	 */
1778 	unsigned long		capacity;
1779 	unsigned long		min_capacity;		/* Min per-CPU capacity in group */
1780 	unsigned long		max_capacity;		/* Max per-CPU capacity in group */
1781 	unsigned long		next_update;
1782 	int			imbalance;		/* XXX unrelated to capacity but shared group state */
1783 
1784 #ifdef CONFIG_SCHED_DEBUG
1785 	int			id;
1786 #endif
1787 
1788 	unsigned long		cpumask[];		/* Balance mask */
1789 };
1790 
1791 struct sched_group {
1792 	struct sched_group	*next;			/* Must be a circular list */
1793 	atomic_t		ref;
1794 
1795 	unsigned int		group_weight;
1796 	struct sched_group_capacity *sgc;
1797 	int			asym_prefer_cpu;	/* CPU of highest priority in group */
1798 	int			flags;
1799 
1800 	/*
1801 	 * The CPUs this group covers.
1802 	 *
1803 	 * NOTE: this field is variable length. (Allocated dynamically
1804 	 * by attaching extra space to the end of the structure,
1805 	 * depending on how many CPUs the kernel has booted up with)
1806 	 */
1807 	unsigned long		cpumask[];
1808 };
1809 
sched_group_span(struct sched_group * sg)1810 static inline struct cpumask *sched_group_span(struct sched_group *sg)
1811 {
1812 	return to_cpumask(sg->cpumask);
1813 }
1814 
1815 /*
1816  * See build_balance_mask().
1817  */
group_balance_mask(struct sched_group * sg)1818 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
1819 {
1820 	return to_cpumask(sg->sgc->cpumask);
1821 }
1822 
1823 /**
1824  * group_first_cpu - Returns the first CPU in the cpumask of a sched_group.
1825  * @group: The group whose first CPU is to be returned.
1826  */
group_first_cpu(struct sched_group * group)1827 static inline unsigned int group_first_cpu(struct sched_group *group)
1828 {
1829 	return cpumask_first(sched_group_span(group));
1830 }
1831 
1832 extern int group_balance_cpu(struct sched_group *sg);
1833 
1834 #ifdef CONFIG_SCHED_DEBUG
1835 void update_sched_domain_debugfs(void);
1836 void dirty_sched_domain_sysctl(int cpu);
1837 #else
update_sched_domain_debugfs(void)1838 static inline void update_sched_domain_debugfs(void)
1839 {
1840 }
dirty_sched_domain_sysctl(int cpu)1841 static inline void dirty_sched_domain_sysctl(int cpu)
1842 {
1843 }
1844 #endif
1845 
1846 extern int sched_update_scaling(void);
1847 
1848 extern void flush_smp_call_function_from_idle(void);
1849 
1850 #else /* !CONFIG_SMP: */
flush_smp_call_function_from_idle(void)1851 static inline void flush_smp_call_function_from_idle(void) { }
1852 #endif
1853 
1854 #include "stats.h"
1855 #include "autogroup.h"
1856 
1857 #ifdef CONFIG_CGROUP_SCHED
1858 
1859 /*
1860  * Return the group to which this tasks belongs.
1861  *
1862  * We cannot use task_css() and friends because the cgroup subsystem
1863  * changes that value before the cgroup_subsys::attach() method is called,
1864  * therefore we cannot pin it and might observe the wrong value.
1865  *
1866  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
1867  * core changes this before calling sched_move_task().
1868  *
1869  * Instead we use a 'copy' which is updated from sched_move_task() while
1870  * holding both task_struct::pi_lock and rq::lock.
1871  */
task_group(struct task_struct * p)1872 static inline struct task_group *task_group(struct task_struct *p)
1873 {
1874 	return p->sched_task_group;
1875 }
1876 
1877 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
set_task_rq(struct task_struct * p,unsigned int cpu)1878 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
1879 {
1880 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
1881 	struct task_group *tg = task_group(p);
1882 #endif
1883 
1884 #ifdef CONFIG_FAIR_GROUP_SCHED
1885 	set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
1886 	p->se.cfs_rq = tg->cfs_rq[cpu];
1887 	p->se.parent = tg->se[cpu];
1888 #endif
1889 
1890 #ifdef CONFIG_RT_GROUP_SCHED
1891 	p->rt.rt_rq  = tg->rt_rq[cpu];
1892 	p->rt.parent = tg->rt_se[cpu];
1893 #endif
1894 }
1895 
1896 #else /* CONFIG_CGROUP_SCHED */
1897 
set_task_rq(struct task_struct * p,unsigned int cpu)1898 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
task_group(struct task_struct * p)1899 static inline struct task_group *task_group(struct task_struct *p)
1900 {
1901 	return NULL;
1902 }
1903 
1904 #endif /* CONFIG_CGROUP_SCHED */
1905 
__set_task_cpu(struct task_struct * p,unsigned int cpu)1906 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
1907 {
1908 	set_task_rq(p, cpu);
1909 #ifdef CONFIG_SMP
1910 	/*
1911 	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
1912 	 * successfully executed on another CPU. We must ensure that updates of
1913 	 * per-task data have been completed by this moment.
1914 	 */
1915 	smp_wmb();
1916 	WRITE_ONCE(task_thread_info(p)->cpu, cpu);
1917 	p->wake_cpu = cpu;
1918 #endif
1919 }
1920 
1921 /*
1922  * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
1923  */
1924 #ifdef CONFIG_SCHED_DEBUG
1925 # include <linux/static_key.h>
1926 # define const_debug __read_mostly
1927 #else
1928 # define const_debug const
1929 #endif
1930 
1931 #define SCHED_FEAT(name, enabled)	\
1932 	__SCHED_FEAT_##name ,
1933 
1934 enum {
1935 #include "features.h"
1936 	__SCHED_FEAT_NR,
1937 };
1938 
1939 #undef SCHED_FEAT
1940 
1941 #ifdef CONFIG_SCHED_DEBUG
1942 
1943 /*
1944  * To support run-time toggling of sched features, all the translation units
1945  * (but core.c) reference the sysctl_sched_features defined in core.c.
1946  */
1947 extern const_debug unsigned int sysctl_sched_features;
1948 
1949 #ifdef CONFIG_JUMP_LABEL
1950 #define SCHED_FEAT(name, enabled)					\
1951 static __always_inline bool static_branch_##name(struct static_key *key) \
1952 {									\
1953 	return static_key_##enabled(key);				\
1954 }
1955 
1956 #include "features.h"
1957 #undef SCHED_FEAT
1958 
1959 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
1960 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
1961 
1962 #else /* !CONFIG_JUMP_LABEL */
1963 
1964 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1965 
1966 #endif /* CONFIG_JUMP_LABEL */
1967 
1968 #else /* !SCHED_DEBUG */
1969 
1970 /*
1971  * Each translation unit has its own copy of sysctl_sched_features to allow
1972  * constants propagation at compile time and compiler optimization based on
1973  * features default.
1974  */
1975 #define SCHED_FEAT(name, enabled)	\
1976 	(1UL << __SCHED_FEAT_##name) * enabled |
1977 static const_debug __maybe_unused unsigned int sysctl_sched_features =
1978 #include "features.h"
1979 	0;
1980 #undef SCHED_FEAT
1981 
1982 #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1983 
1984 #endif /* SCHED_DEBUG */
1985 
1986 extern struct static_key_false sched_numa_balancing;
1987 extern struct static_key_false sched_schedstats;
1988 
global_rt_period(void)1989 static inline u64 global_rt_period(void)
1990 {
1991 	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
1992 }
1993 
global_rt_runtime(void)1994 static inline u64 global_rt_runtime(void)
1995 {
1996 	if (sysctl_sched_rt_runtime < 0)
1997 		return RUNTIME_INF;
1998 
1999 	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
2000 }
2001 
task_current(struct rq * rq,struct task_struct * p)2002 static inline int task_current(struct rq *rq, struct task_struct *p)
2003 {
2004 	return rq->curr == p;
2005 }
2006 
task_running(struct rq * rq,struct task_struct * p)2007 static inline int task_running(struct rq *rq, struct task_struct *p)
2008 {
2009 #ifdef CONFIG_SMP
2010 	return p->on_cpu;
2011 #else
2012 	return task_current(rq, p);
2013 #endif
2014 }
2015 
task_on_rq_queued(struct task_struct * p)2016 static inline int task_on_rq_queued(struct task_struct *p)
2017 {
2018 	return p->on_rq == TASK_ON_RQ_QUEUED;
2019 }
2020 
task_on_rq_migrating(struct task_struct * p)2021 static inline int task_on_rq_migrating(struct task_struct *p)
2022 {
2023 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
2024 }
2025 
2026 /* Wake flags. The first three directly map to some SD flag value */
2027 #define WF_EXEC     0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
2028 #define WF_FORK     0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
2029 #define WF_TTWU     0x08 /* Wakeup;            maps to SD_BALANCE_WAKE */
2030 
2031 #define WF_SYNC     0x10 /* Waker goes to sleep after wakeup */
2032 #define WF_MIGRATED 0x20 /* Internal use, task got migrated */
2033 #define WF_ON_CPU   0x40 /* Wakee is on_cpu */
2034 
2035 #ifdef CONFIG_SMP
2036 static_assert(WF_EXEC == SD_BALANCE_EXEC);
2037 static_assert(WF_FORK == SD_BALANCE_FORK);
2038 static_assert(WF_TTWU == SD_BALANCE_WAKE);
2039 #endif
2040 
2041 /*
2042  * To aid in avoiding the subversion of "niceness" due to uneven distribution
2043  * of tasks with abnormal "nice" values across CPUs the contribution that
2044  * each task makes to its run queue's load is weighted according to its
2045  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
2046  * scaled version of the new time slice allocation that they receive on time
2047  * slice expiry etc.
2048  */
2049 
2050 #define WEIGHT_IDLEPRIO		3
2051 #define WMULT_IDLEPRIO		1431655765
2052 
2053 extern const int		sched_prio_to_weight[40];
2054 extern const u32		sched_prio_to_wmult[40];
2055 
2056 /*
2057  * {de,en}queue flags:
2058  *
2059  * DEQUEUE_SLEEP  - task is no longer runnable
2060  * ENQUEUE_WAKEUP - task just became runnable
2061  *
2062  * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
2063  *                are in a known state which allows modification. Such pairs
2064  *                should preserve as much state as possible.
2065  *
2066  * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
2067  *        in the runqueue.
2068  *
2069  * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
2070  * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
2071  * ENQUEUE_MIGRATED  - the task was migrated during wakeup
2072  *
2073  */
2074 
2075 #define DEQUEUE_SLEEP		0x01
2076 #define DEQUEUE_SAVE		0x02 /* Matches ENQUEUE_RESTORE */
2077 #define DEQUEUE_MOVE		0x04 /* Matches ENQUEUE_MOVE */
2078 #define DEQUEUE_NOCLOCK		0x08 /* Matches ENQUEUE_NOCLOCK */
2079 
2080 #define ENQUEUE_WAKEUP		0x01
2081 #define ENQUEUE_RESTORE		0x02
2082 #define ENQUEUE_MOVE		0x04
2083 #define ENQUEUE_NOCLOCK		0x08
2084 
2085 #define ENQUEUE_HEAD		0x10
2086 #define ENQUEUE_REPLENISH	0x20
2087 #ifdef CONFIG_SMP
2088 #define ENQUEUE_MIGRATED	0x40
2089 #else
2090 #define ENQUEUE_MIGRATED	0x00
2091 #endif
2092 
2093 #define RETRY_TASK		((void *)-1UL)
2094 
2095 struct sched_class {
2096 
2097 #ifdef CONFIG_UCLAMP_TASK
2098 	int uclamp_enabled;
2099 #endif
2100 
2101 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
2102 	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
2103 	void (*yield_task)   (struct rq *rq);
2104 	bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
2105 
2106 	void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags);
2107 
2108 	struct task_struct *(*pick_next_task)(struct rq *rq);
2109 
2110 	void (*put_prev_task)(struct rq *rq, struct task_struct *p);
2111 	void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
2112 
2113 #ifdef CONFIG_SMP
2114 	int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2115 	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
2116 
2117 	struct task_struct * (*pick_task)(struct rq *rq);
2118 
2119 	void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
2120 
2121 	void (*task_woken)(struct rq *this_rq, struct task_struct *task);
2122 
2123 	void (*set_cpus_allowed)(struct task_struct *p,
2124 				 const struct cpumask *newmask,
2125 				 u32 flags);
2126 
2127 	void (*rq_online)(struct rq *rq);
2128 	void (*rq_offline)(struct rq *rq);
2129 
2130 	struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
2131 #endif
2132 
2133 	void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
2134 	void (*task_fork)(struct task_struct *p);
2135 	void (*task_dead)(struct task_struct *p);
2136 
2137 	/*
2138 	 * The switched_from() call is allowed to drop rq->lock, therefore we
2139 	 * cannot assume the switched_from/switched_to pair is serialized by
2140 	 * rq->lock. They are however serialized by p->pi_lock.
2141 	 */
2142 	void (*switched_from)(struct rq *this_rq, struct task_struct *task);
2143 	void (*switched_to)  (struct rq *this_rq, struct task_struct *task);
2144 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
2145 			      int oldprio);
2146 
2147 	unsigned int (*get_rr_interval)(struct rq *rq,
2148 					struct task_struct *task);
2149 
2150 	void (*update_curr)(struct rq *rq);
2151 
2152 #define TASK_SET_GROUP		0
2153 #define TASK_MOVE_GROUP		1
2154 
2155 #ifdef CONFIG_FAIR_GROUP_SCHED
2156 	void (*task_change_group)(struct task_struct *p, int type);
2157 #endif
2158 };
2159 
put_prev_task(struct rq * rq,struct task_struct * prev)2160 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
2161 {
2162 	WARN_ON_ONCE(rq->curr != prev);
2163 	prev->sched_class->put_prev_task(rq, prev);
2164 }
2165 
set_next_task(struct rq * rq,struct task_struct * next)2166 static inline void set_next_task(struct rq *rq, struct task_struct *next)
2167 {
2168 	next->sched_class->set_next_task(rq, next, false);
2169 }
2170 
2171 
2172 /*
2173  * Helper to define a sched_class instance; each one is placed in a separate
2174  * section which is ordered by the linker script:
2175  *
2176  *   include/asm-generic/vmlinux.lds.h
2177  *
2178  * Also enforce alignment on the instance, not the type, to guarantee layout.
2179  */
2180 #define DEFINE_SCHED_CLASS(name) \
2181 const struct sched_class name##_sched_class \
2182 	__aligned(__alignof__(struct sched_class)) \
2183 	__section("__" #name "_sched_class")
2184 
2185 /* Defined in include/asm-generic/vmlinux.lds.h */
2186 extern struct sched_class __begin_sched_classes[];
2187 extern struct sched_class __end_sched_classes[];
2188 
2189 #define sched_class_highest (__end_sched_classes - 1)
2190 #define sched_class_lowest  (__begin_sched_classes - 1)
2191 
2192 #define for_class_range(class, _from, _to) \
2193 	for (class = (_from); class != (_to); class--)
2194 
2195 #define for_each_class(class) \
2196 	for_class_range(class, sched_class_highest, sched_class_lowest)
2197 
2198 extern const struct sched_class stop_sched_class;
2199 extern const struct sched_class dl_sched_class;
2200 extern const struct sched_class rt_sched_class;
2201 extern const struct sched_class fair_sched_class;
2202 extern const struct sched_class idle_sched_class;
2203 
sched_stop_runnable(struct rq * rq)2204 static inline bool sched_stop_runnable(struct rq *rq)
2205 {
2206 	return rq->stop && task_on_rq_queued(rq->stop);
2207 }
2208 
sched_dl_runnable(struct rq * rq)2209 static inline bool sched_dl_runnable(struct rq *rq)
2210 {
2211 	return rq->dl.dl_nr_running > 0;
2212 }
2213 
sched_rt_runnable(struct rq * rq)2214 static inline bool sched_rt_runnable(struct rq *rq)
2215 {
2216 	return rq->rt.rt_queued > 0;
2217 }
2218 
sched_fair_runnable(struct rq * rq)2219 static inline bool sched_fair_runnable(struct rq *rq)
2220 {
2221 	return rq->cfs.nr_running > 0;
2222 }
2223 
2224 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2225 extern struct task_struct *pick_next_task_idle(struct rq *rq);
2226 
2227 #define SCA_CHECK		0x01
2228 #define SCA_MIGRATE_DISABLE	0x02
2229 #define SCA_MIGRATE_ENABLE	0x04
2230 #define SCA_USER		0x08
2231 
2232 #ifdef CONFIG_SMP
2233 
2234 extern void update_group_capacity(struct sched_domain *sd, int cpu);
2235 
2236 extern void trigger_load_balance(struct rq *rq);
2237 
2238 extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask, u32 flags);
2239 
get_push_task(struct rq * rq)2240 static inline struct task_struct *get_push_task(struct rq *rq)
2241 {
2242 	struct task_struct *p = rq->curr;
2243 
2244 	lockdep_assert_rq_held(rq);
2245 
2246 	if (rq->push_busy)
2247 		return NULL;
2248 
2249 	if (p->nr_cpus_allowed == 1)
2250 		return NULL;
2251 
2252 	if (p->migration_disabled)
2253 		return NULL;
2254 
2255 	rq->push_busy = true;
2256 	return get_task_struct(p);
2257 }
2258 
2259 extern int push_cpu_stop(void *arg);
2260 
2261 #endif
2262 
2263 #ifdef CONFIG_CPU_IDLE
idle_set_state(struct rq * rq,struct cpuidle_state * idle_state)2264 static inline void idle_set_state(struct rq *rq,
2265 				  struct cpuidle_state *idle_state)
2266 {
2267 	rq->idle_state = idle_state;
2268 }
2269 
idle_get_state(struct rq * rq)2270 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2271 {
2272 	SCHED_WARN_ON(!rcu_read_lock_held());
2273 
2274 	return rq->idle_state;
2275 }
2276 #else
idle_set_state(struct rq * rq,struct cpuidle_state * idle_state)2277 static inline void idle_set_state(struct rq *rq,
2278 				  struct cpuidle_state *idle_state)
2279 {
2280 }
2281 
idle_get_state(struct rq * rq)2282 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2283 {
2284 	return NULL;
2285 }
2286 #endif
2287 
2288 extern void schedule_idle(void);
2289 
2290 extern void sysrq_sched_debug_show(void);
2291 extern void sched_init_granularity(void);
2292 extern void update_max_interval(void);
2293 
2294 extern void init_sched_dl_class(void);
2295 extern void init_sched_rt_class(void);
2296 extern void init_sched_fair_class(void);
2297 
2298 extern void reweight_task(struct task_struct *p, int prio);
2299 
2300 extern void resched_curr(struct rq *rq);
2301 extern void resched_cpu(int cpu);
2302 
2303 extern struct rt_bandwidth def_rt_bandwidth;
2304 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
2305 
2306 extern struct dl_bandwidth def_dl_bandwidth;
2307 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
2308 extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
2309 extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se);
2310 
2311 #define BW_SHIFT		20
2312 #define BW_UNIT			(1 << BW_SHIFT)
2313 #define RATIO_SHIFT		8
2314 #define MAX_BW_BITS		(64 - BW_SHIFT)
2315 #define MAX_BW			((1ULL << MAX_BW_BITS) - 1)
2316 unsigned long to_ratio(u64 period, u64 runtime);
2317 
2318 extern void init_entity_runnable_average(struct sched_entity *se);
2319 extern void post_init_entity_util_avg(struct task_struct *p);
2320 
2321 #ifdef CONFIG_NO_HZ_FULL
2322 extern bool sched_can_stop_tick(struct rq *rq);
2323 extern int __init sched_tick_offload_init(void);
2324 
2325 /*
2326  * Tick may be needed by tasks in the runqueue depending on their policy and
2327  * requirements. If tick is needed, lets send the target an IPI to kick it out of
2328  * nohz mode if necessary.
2329  */
sched_update_tick_dependency(struct rq * rq)2330 static inline void sched_update_tick_dependency(struct rq *rq)
2331 {
2332 	int cpu = cpu_of(rq);
2333 
2334 	if (!tick_nohz_full_cpu(cpu))
2335 		return;
2336 
2337 	if (sched_can_stop_tick(rq))
2338 		tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
2339 	else
2340 		tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
2341 }
2342 #else
sched_tick_offload_init(void)2343 static inline int sched_tick_offload_init(void) { return 0; }
sched_update_tick_dependency(struct rq * rq)2344 static inline void sched_update_tick_dependency(struct rq *rq) { }
2345 #endif
2346 
add_nr_running(struct rq * rq,unsigned count)2347 static inline void add_nr_running(struct rq *rq, unsigned count)
2348 {
2349 	unsigned prev_nr = rq->nr_running;
2350 
2351 	rq->nr_running = prev_nr + count;
2352 	if (trace_sched_update_nr_running_tp_enabled()) {
2353 		call_trace_sched_update_nr_running(rq, count);
2354 	}
2355 
2356 #ifdef CONFIG_SMP
2357 	if (prev_nr < 2 && rq->nr_running >= 2) {
2358 		if (!READ_ONCE(rq->rd->overload))
2359 			WRITE_ONCE(rq->rd->overload, 1);
2360 	}
2361 #endif
2362 
2363 	sched_update_tick_dependency(rq);
2364 }
2365 
sub_nr_running(struct rq * rq,unsigned count)2366 static inline void sub_nr_running(struct rq *rq, unsigned count)
2367 {
2368 	rq->nr_running -= count;
2369 	if (trace_sched_update_nr_running_tp_enabled()) {
2370 		call_trace_sched_update_nr_running(rq, -count);
2371 	}
2372 
2373 	/* Check if we still need preemption */
2374 	sched_update_tick_dependency(rq);
2375 }
2376 
2377 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
2378 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
2379 
2380 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
2381 
2382 extern const_debug unsigned int sysctl_sched_nr_migrate;
2383 extern const_debug unsigned int sysctl_sched_migration_cost;
2384 
2385 #ifdef CONFIG_SCHED_DEBUG
2386 extern unsigned int sysctl_sched_latency;
2387 extern unsigned int sysctl_sched_min_granularity;
2388 extern unsigned int sysctl_sched_idle_min_granularity;
2389 extern unsigned int sysctl_sched_wakeup_granularity;
2390 extern int sysctl_resched_latency_warn_ms;
2391 extern int sysctl_resched_latency_warn_once;
2392 
2393 extern unsigned int sysctl_sched_tunable_scaling;
2394 
2395 extern unsigned int sysctl_numa_balancing_scan_delay;
2396 extern unsigned int sysctl_numa_balancing_scan_period_min;
2397 extern unsigned int sysctl_numa_balancing_scan_period_max;
2398 extern unsigned int sysctl_numa_balancing_scan_size;
2399 #endif
2400 
2401 #ifdef CONFIG_SCHED_HRTICK
2402 
2403 /*
2404  * Use hrtick when:
2405  *  - enabled by features
2406  *  - hrtimer is actually high res
2407  */
hrtick_enabled(struct rq * rq)2408 static inline int hrtick_enabled(struct rq *rq)
2409 {
2410 	if (!cpu_active(cpu_of(rq)))
2411 		return 0;
2412 	return hrtimer_is_hres_active(&rq->hrtick_timer);
2413 }
2414 
hrtick_enabled_fair(struct rq * rq)2415 static inline int hrtick_enabled_fair(struct rq *rq)
2416 {
2417 	if (!sched_feat(HRTICK))
2418 		return 0;
2419 	return hrtick_enabled(rq);
2420 }
2421 
hrtick_enabled_dl(struct rq * rq)2422 static inline int hrtick_enabled_dl(struct rq *rq)
2423 {
2424 	if (!sched_feat(HRTICK_DL))
2425 		return 0;
2426 	return hrtick_enabled(rq);
2427 }
2428 
2429 void hrtick_start(struct rq *rq, u64 delay);
2430 
2431 #else
2432 
hrtick_enabled_fair(struct rq * rq)2433 static inline int hrtick_enabled_fair(struct rq *rq)
2434 {
2435 	return 0;
2436 }
2437 
hrtick_enabled_dl(struct rq * rq)2438 static inline int hrtick_enabled_dl(struct rq *rq)
2439 {
2440 	return 0;
2441 }
2442 
hrtick_enabled(struct rq * rq)2443 static inline int hrtick_enabled(struct rq *rq)
2444 {
2445 	return 0;
2446 }
2447 
2448 #endif /* CONFIG_SCHED_HRTICK */
2449 
2450 #ifndef arch_scale_freq_tick
2451 static __always_inline
arch_scale_freq_tick(void)2452 void arch_scale_freq_tick(void)
2453 {
2454 }
2455 #endif
2456 
2457 #ifndef arch_scale_freq_capacity
2458 /**
2459  * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
2460  * @cpu: the CPU in question.
2461  *
2462  * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
2463  *
2464  *     f_curr
2465  *     ------ * SCHED_CAPACITY_SCALE
2466  *     f_max
2467  */
2468 static __always_inline
arch_scale_freq_capacity(int cpu)2469 unsigned long arch_scale_freq_capacity(int cpu)
2470 {
2471 	return SCHED_CAPACITY_SCALE;
2472 }
2473 #endif
2474 
2475 
2476 #ifdef CONFIG_SMP
2477 
rq_order_less(struct rq * rq1,struct rq * rq2)2478 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2)
2479 {
2480 #ifdef CONFIG_SCHED_CORE
2481 	/*
2482 	 * In order to not have {0,2},{1,3} turn into into an AB-BA,
2483 	 * order by core-id first and cpu-id second.
2484 	 *
2485 	 * Notably:
2486 	 *
2487 	 *	double_rq_lock(0,3); will take core-0, core-1 lock
2488 	 *	double_rq_lock(1,2); will take core-1, core-0 lock
2489 	 *
2490 	 * when only cpu-id is considered.
2491 	 */
2492 	if (rq1->core->cpu < rq2->core->cpu)
2493 		return true;
2494 	if (rq1->core->cpu > rq2->core->cpu)
2495 		return false;
2496 
2497 	/*
2498 	 * __sched_core_flip() relies on SMT having cpu-id lock order.
2499 	 */
2500 #endif
2501 	return rq1->cpu < rq2->cpu;
2502 }
2503 
2504 extern void double_rq_lock(struct rq *rq1, struct rq *rq2);
2505 
2506 #ifdef CONFIG_PREEMPTION
2507 
2508 /*
2509  * fair double_lock_balance: Safely acquires both rq->locks in a fair
2510  * way at the expense of forcing extra atomic operations in all
2511  * invocations.  This assures that the double_lock is acquired using the
2512  * same underlying policy as the spinlock_t on this architecture, which
2513  * reduces latency compared to the unfair variant below.  However, it
2514  * also adds more overhead and therefore may reduce throughput.
2515  */
_double_lock_balance(struct rq * this_rq,struct rq * busiest)2516 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2517 	__releases(this_rq->lock)
2518 	__acquires(busiest->lock)
2519 	__acquires(this_rq->lock)
2520 {
2521 	raw_spin_rq_unlock(this_rq);
2522 	double_rq_lock(this_rq, busiest);
2523 
2524 	return 1;
2525 }
2526 
2527 #else
2528 /*
2529  * Unfair double_lock_balance: Optimizes throughput at the expense of
2530  * latency by eliminating extra atomic operations when the locks are
2531  * already in proper order on entry.  This favors lower CPU-ids and will
2532  * grant the double lock to lower CPUs over higher ids under contention,
2533  * regardless of entry order into the function.
2534  */
_double_lock_balance(struct rq * this_rq,struct rq * busiest)2535 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2536 	__releases(this_rq->lock)
2537 	__acquires(busiest->lock)
2538 	__acquires(this_rq->lock)
2539 {
2540 	if (__rq_lockp(this_rq) == __rq_lockp(busiest))
2541 		return 0;
2542 
2543 	if (likely(raw_spin_rq_trylock(busiest)))
2544 		return 0;
2545 
2546 	if (rq_order_less(this_rq, busiest)) {
2547 		raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING);
2548 		return 0;
2549 	}
2550 
2551 	raw_spin_rq_unlock(this_rq);
2552 	double_rq_lock(this_rq, busiest);
2553 
2554 	return 1;
2555 }
2556 
2557 #endif /* CONFIG_PREEMPTION */
2558 
2559 /*
2560  * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
2561  */
double_lock_balance(struct rq * this_rq,struct rq * busiest)2562 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
2563 {
2564 	lockdep_assert_irqs_disabled();
2565 
2566 	return _double_lock_balance(this_rq, busiest);
2567 }
2568 
double_unlock_balance(struct rq * this_rq,struct rq * busiest)2569 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
2570 	__releases(busiest->lock)
2571 {
2572 	if (__rq_lockp(this_rq) != __rq_lockp(busiest))
2573 		raw_spin_rq_unlock(busiest);
2574 	lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_);
2575 }
2576 
double_lock(spinlock_t * l1,spinlock_t * l2)2577 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
2578 {
2579 	if (l1 > l2)
2580 		swap(l1, l2);
2581 
2582 	spin_lock(l1);
2583 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2584 }
2585 
double_lock_irq(spinlock_t * l1,spinlock_t * l2)2586 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
2587 {
2588 	if (l1 > l2)
2589 		swap(l1, l2);
2590 
2591 	spin_lock_irq(l1);
2592 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2593 }
2594 
double_raw_lock(raw_spinlock_t * l1,raw_spinlock_t * l2)2595 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
2596 {
2597 	if (l1 > l2)
2598 		swap(l1, l2);
2599 
2600 	raw_spin_lock(l1);
2601 	raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2602 }
2603 
2604 /*
2605  * double_rq_unlock - safely unlock two runqueues
2606  *
2607  * Note this does not restore interrupts like task_rq_unlock,
2608  * you need to do so manually after calling.
2609  */
double_rq_unlock(struct rq * rq1,struct rq * rq2)2610 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2611 	__releases(rq1->lock)
2612 	__releases(rq2->lock)
2613 {
2614 	if (__rq_lockp(rq1) != __rq_lockp(rq2))
2615 		raw_spin_rq_unlock(rq2);
2616 	else
2617 		__release(rq2->lock);
2618 	raw_spin_rq_unlock(rq1);
2619 }
2620 
2621 extern void set_rq_online (struct rq *rq);
2622 extern void set_rq_offline(struct rq *rq);
2623 extern bool sched_smp_initialized;
2624 
2625 #else /* CONFIG_SMP */
2626 
2627 /*
2628  * double_rq_lock - safely lock two runqueues
2629  *
2630  * Note this does not disable interrupts like task_rq_lock,
2631  * you need to do so manually before calling.
2632  */
double_rq_lock(struct rq * rq1,struct rq * rq2)2633 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2634 	__acquires(rq1->lock)
2635 	__acquires(rq2->lock)
2636 {
2637 	BUG_ON(!irqs_disabled());
2638 	BUG_ON(rq1 != rq2);
2639 	raw_spin_rq_lock(rq1);
2640 	__acquire(rq2->lock);	/* Fake it out ;) */
2641 }
2642 
2643 /*
2644  * double_rq_unlock - safely unlock two runqueues
2645  *
2646  * Note this does not restore interrupts like task_rq_unlock,
2647  * you need to do so manually after calling.
2648  */
double_rq_unlock(struct rq * rq1,struct rq * rq2)2649 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2650 	__releases(rq1->lock)
2651 	__releases(rq2->lock)
2652 {
2653 	BUG_ON(rq1 != rq2);
2654 	raw_spin_rq_unlock(rq1);
2655 	__release(rq2->lock);
2656 }
2657 
2658 #endif
2659 
2660 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
2661 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
2662 
2663 #ifdef	CONFIG_SCHED_DEBUG
2664 extern bool sched_debug_verbose;
2665 
2666 extern void print_cfs_stats(struct seq_file *m, int cpu);
2667 extern void print_rt_stats(struct seq_file *m, int cpu);
2668 extern void print_dl_stats(struct seq_file *m, int cpu);
2669 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
2670 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
2671 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
2672 
2673 extern void resched_latency_warn(int cpu, u64 latency);
2674 #ifdef CONFIG_NUMA_BALANCING
2675 extern void
2676 show_numa_stats(struct task_struct *p, struct seq_file *m);
2677 extern void
2678 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
2679 	unsigned long tpf, unsigned long gsf, unsigned long gpf);
2680 #endif /* CONFIG_NUMA_BALANCING */
2681 #else
resched_latency_warn(int cpu,u64 latency)2682 static inline void resched_latency_warn(int cpu, u64 latency) {}
2683 #endif /* CONFIG_SCHED_DEBUG */
2684 
2685 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
2686 extern void init_rt_rq(struct rt_rq *rt_rq);
2687 extern void init_dl_rq(struct dl_rq *dl_rq);
2688 
2689 extern void cfs_bandwidth_usage_inc(void);
2690 extern void cfs_bandwidth_usage_dec(void);
2691 
2692 #ifdef CONFIG_NO_HZ_COMMON
2693 #define NOHZ_BALANCE_KICK_BIT	0
2694 #define NOHZ_STATS_KICK_BIT	1
2695 #define NOHZ_NEWILB_KICK_BIT	2
2696 #define NOHZ_NEXT_KICK_BIT	3
2697 
2698 /* Run rebalance_domains() */
2699 #define NOHZ_BALANCE_KICK	BIT(NOHZ_BALANCE_KICK_BIT)
2700 /* Update blocked load */
2701 #define NOHZ_STATS_KICK		BIT(NOHZ_STATS_KICK_BIT)
2702 /* Update blocked load when entering idle */
2703 #define NOHZ_NEWILB_KICK	BIT(NOHZ_NEWILB_KICK_BIT)
2704 /* Update nohz.next_balance */
2705 #define NOHZ_NEXT_KICK		BIT(NOHZ_NEXT_KICK_BIT)
2706 
2707 #define NOHZ_KICK_MASK	(NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK)
2708 
2709 #define nohz_flags(cpu)	(&cpu_rq(cpu)->nohz_flags)
2710 
2711 extern void nohz_balance_exit_idle(struct rq *rq);
2712 #else
nohz_balance_exit_idle(struct rq * rq)2713 static inline void nohz_balance_exit_idle(struct rq *rq) { }
2714 #endif
2715 
2716 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
2717 extern void nohz_run_idle_balance(int cpu);
2718 #else
nohz_run_idle_balance(int cpu)2719 static inline void nohz_run_idle_balance(int cpu) { }
2720 #endif
2721 
2722 #ifdef CONFIG_SMP
2723 static inline
__dl_update(struct dl_bw * dl_b,s64 bw)2724 void __dl_update(struct dl_bw *dl_b, s64 bw)
2725 {
2726 	struct root_domain *rd = container_of(dl_b, struct root_domain, dl_bw);
2727 	int i;
2728 
2729 	RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
2730 			 "sched RCU must be held");
2731 	for_each_cpu_and(i, rd->span, cpu_active_mask) {
2732 		struct rq *rq = cpu_rq(i);
2733 
2734 		rq->dl.extra_bw += bw;
2735 	}
2736 }
2737 #else
2738 static inline
__dl_update(struct dl_bw * dl_b,s64 bw)2739 void __dl_update(struct dl_bw *dl_b, s64 bw)
2740 {
2741 	struct dl_rq *dl = container_of(dl_b, struct dl_rq, dl_bw);
2742 
2743 	dl->extra_bw += bw;
2744 }
2745 #endif
2746 
2747 
2748 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2749 struct irqtime {
2750 	u64			total;
2751 	u64			tick_delta;
2752 	u64			irq_start_time;
2753 	struct u64_stats_sync	sync;
2754 };
2755 
2756 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
2757 
2758 /*
2759  * Returns the irqtime minus the softirq time computed by ksoftirqd.
2760  * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime
2761  * and never move forward.
2762  */
irq_time_read(int cpu)2763 static inline u64 irq_time_read(int cpu)
2764 {
2765 	struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
2766 	unsigned int seq;
2767 	u64 total;
2768 
2769 	do {
2770 		seq = __u64_stats_fetch_begin(&irqtime->sync);
2771 		total = irqtime->total;
2772 	} while (__u64_stats_fetch_retry(&irqtime->sync, seq));
2773 
2774 	return total;
2775 }
2776 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
2777 
2778 #ifdef CONFIG_CPU_FREQ
2779 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
2780 
2781 /**
2782  * cpufreq_update_util - Take a note about CPU utilization changes.
2783  * @rq: Runqueue to carry out the update for.
2784  * @flags: Update reason flags.
2785  *
2786  * This function is called by the scheduler on the CPU whose utilization is
2787  * being updated.
2788  *
2789  * It can only be called from RCU-sched read-side critical sections.
2790  *
2791  * The way cpufreq is currently arranged requires it to evaluate the CPU
2792  * performance state (frequency/voltage) on a regular basis to prevent it from
2793  * being stuck in a completely inadequate performance level for too long.
2794  * That is not guaranteed to happen if the updates are only triggered from CFS
2795  * and DL, though, because they may not be coming in if only RT tasks are
2796  * active all the time (or there are RT tasks only).
2797  *
2798  * As a workaround for that issue, this function is called periodically by the
2799  * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
2800  * but that really is a band-aid.  Going forward it should be replaced with
2801  * solutions targeted more specifically at RT tasks.
2802  */
cpufreq_update_util(struct rq * rq,unsigned int flags)2803 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
2804 {
2805 	struct update_util_data *data;
2806 
2807 	data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
2808 						  cpu_of(rq)));
2809 	if (data)
2810 		data->func(data, rq_clock(rq), flags);
2811 }
2812 #else
cpufreq_update_util(struct rq * rq,unsigned int flags)2813 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
2814 #endif /* CONFIG_CPU_FREQ */
2815 
2816 #ifdef CONFIG_UCLAMP_TASK
2817 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
2818 
2819 /**
2820  * uclamp_rq_util_with - clamp @util with @rq and @p effective uclamp values.
2821  * @rq:		The rq to clamp against. Must not be NULL.
2822  * @util:	The util value to clamp.
2823  * @p:		The task to clamp against. Can be NULL if you want to clamp
2824  *		against @rq only.
2825  *
2826  * Clamps the passed @util to the max(@rq, @p) effective uclamp values.
2827  *
2828  * If sched_uclamp_used static key is disabled, then just return the util
2829  * without any clamping since uclamp aggregation at the rq level in the fast
2830  * path is disabled, rendering this operation a NOP.
2831  *
2832  * Use uclamp_eff_value() if you don't care about uclamp values at rq level. It
2833  * will return the correct effective uclamp value of the task even if the
2834  * static key is disabled.
2835  */
2836 static __always_inline
uclamp_rq_util_with(struct rq * rq,unsigned long util,struct task_struct * p)2837 unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
2838 				  struct task_struct *p)
2839 {
2840 	unsigned long min_util = 0;
2841 	unsigned long max_util = 0;
2842 
2843 	if (!static_branch_likely(&sched_uclamp_used))
2844 		return util;
2845 
2846 	if (p) {
2847 		min_util = uclamp_eff_value(p, UCLAMP_MIN);
2848 		max_util = uclamp_eff_value(p, UCLAMP_MAX);
2849 
2850 		/*
2851 		 * Ignore last runnable task's max clamp, as this task will
2852 		 * reset it. Similarly, no need to read the rq's min clamp.
2853 		 */
2854 		if (rq->uclamp_flags & UCLAMP_FLAG_IDLE)
2855 			goto out;
2856 	}
2857 
2858 	min_util = max_t(unsigned long, min_util, READ_ONCE(rq->uclamp[UCLAMP_MIN].value));
2859 	max_util = max_t(unsigned long, max_util, READ_ONCE(rq->uclamp[UCLAMP_MAX].value));
2860 out:
2861 	/*
2862 	 * Since CPU's {min,max}_util clamps are MAX aggregated considering
2863 	 * RUNNABLE tasks with _different_ clamps, we can end up with an
2864 	 * inversion. Fix it now when the clamps are applied.
2865 	 */
2866 	if (unlikely(min_util >= max_util))
2867 		return min_util;
2868 
2869 	return clamp(util, min_util, max_util);
2870 }
2871 
2872 /*
2873  * When uclamp is compiled in, the aggregation at rq level is 'turned off'
2874  * by default in the fast path and only gets turned on once userspace performs
2875  * an operation that requires it.
2876  *
2877  * Returns true if userspace opted-in to use uclamp and aggregation at rq level
2878  * hence is active.
2879  */
uclamp_is_used(void)2880 static inline bool uclamp_is_used(void)
2881 {
2882 	return static_branch_likely(&sched_uclamp_used);
2883 }
2884 #else /* CONFIG_UCLAMP_TASK */
2885 static inline
uclamp_rq_util_with(struct rq * rq,unsigned long util,struct task_struct * p)2886 unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
2887 				  struct task_struct *p)
2888 {
2889 	return util;
2890 }
2891 
uclamp_is_used(void)2892 static inline bool uclamp_is_used(void)
2893 {
2894 	return false;
2895 }
2896 #endif /* CONFIG_UCLAMP_TASK */
2897 
2898 #ifdef arch_scale_freq_capacity
2899 # ifndef arch_scale_freq_invariant
2900 #  define arch_scale_freq_invariant()	true
2901 # endif
2902 #else
2903 # define arch_scale_freq_invariant()	false
2904 #endif
2905 
2906 #ifdef CONFIG_SMP
capacity_orig_of(int cpu)2907 static inline unsigned long capacity_orig_of(int cpu)
2908 {
2909 	return cpu_rq(cpu)->cpu_capacity_orig;
2910 }
2911 
2912 /**
2913  * enum cpu_util_type - CPU utilization type
2914  * @FREQUENCY_UTIL:	Utilization used to select frequency
2915  * @ENERGY_UTIL:	Utilization used during energy calculation
2916  *
2917  * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time
2918  * need to be aggregated differently depending on the usage made of them. This
2919  * enum is used within effective_cpu_util() to differentiate the types of
2920  * utilization expected by the callers, and adjust the aggregation accordingly.
2921  */
2922 enum cpu_util_type {
2923 	FREQUENCY_UTIL,
2924 	ENERGY_UTIL,
2925 };
2926 
2927 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
2928 				 unsigned long max, enum cpu_util_type type,
2929 				 struct task_struct *p);
2930 
cpu_bw_dl(struct rq * rq)2931 static inline unsigned long cpu_bw_dl(struct rq *rq)
2932 {
2933 	return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
2934 }
2935 
cpu_util_dl(struct rq * rq)2936 static inline unsigned long cpu_util_dl(struct rq *rq)
2937 {
2938 	return READ_ONCE(rq->avg_dl.util_avg);
2939 }
2940 
cpu_util_cfs(struct rq * rq)2941 static inline unsigned long cpu_util_cfs(struct rq *rq)
2942 {
2943 	unsigned long util = READ_ONCE(rq->cfs.avg.util_avg);
2944 
2945 	if (sched_feat(UTIL_EST)) {
2946 		util = max_t(unsigned long, util,
2947 			     READ_ONCE(rq->cfs.avg.util_est.enqueued));
2948 	}
2949 
2950 	return util;
2951 }
2952 
cpu_util_rt(struct rq * rq)2953 static inline unsigned long cpu_util_rt(struct rq *rq)
2954 {
2955 	return READ_ONCE(rq->avg_rt.util_avg);
2956 }
2957 #endif
2958 
2959 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
cpu_util_irq(struct rq * rq)2960 static inline unsigned long cpu_util_irq(struct rq *rq)
2961 {
2962 	return rq->avg_irq.util_avg;
2963 }
2964 
2965 static inline
scale_irq_capacity(unsigned long util,unsigned long irq,unsigned long max)2966 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2967 {
2968 	util *= (max - irq);
2969 	util /= max;
2970 
2971 	return util;
2972 
2973 }
2974 #else
cpu_util_irq(struct rq * rq)2975 static inline unsigned long cpu_util_irq(struct rq *rq)
2976 {
2977 	return 0;
2978 }
2979 
2980 static inline
scale_irq_capacity(unsigned long util,unsigned long irq,unsigned long max)2981 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2982 {
2983 	return util;
2984 }
2985 #endif
2986 
2987 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
2988 
2989 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
2990 
2991 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
2992 
sched_energy_enabled(void)2993 static inline bool sched_energy_enabled(void)
2994 {
2995 	return static_branch_unlikely(&sched_energy_present);
2996 }
2997 
2998 #else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
2999 
3000 #define perf_domain_span(pd) NULL
sched_energy_enabled(void)3001 static inline bool sched_energy_enabled(void) { return false; }
3002 
3003 #endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
3004 
3005 #ifdef CONFIG_MEMBARRIER
3006 /*
3007  * The scheduler provides memory barriers required by membarrier between:
3008  * - prior user-space memory accesses and store to rq->membarrier_state,
3009  * - store to rq->membarrier_state and following user-space memory accesses.
3010  * In the same way it provides those guarantees around store to rq->curr.
3011  */
membarrier_switch_mm(struct rq * rq,struct mm_struct * prev_mm,struct mm_struct * next_mm)3012 static inline void membarrier_switch_mm(struct rq *rq,
3013 					struct mm_struct *prev_mm,
3014 					struct mm_struct *next_mm)
3015 {
3016 	int membarrier_state;
3017 
3018 	if (prev_mm == next_mm)
3019 		return;
3020 
3021 	membarrier_state = atomic_read(&next_mm->membarrier_state);
3022 	if (READ_ONCE(rq->membarrier_state) == membarrier_state)
3023 		return;
3024 
3025 	WRITE_ONCE(rq->membarrier_state, membarrier_state);
3026 }
3027 #else
membarrier_switch_mm(struct rq * rq,struct mm_struct * prev_mm,struct mm_struct * next_mm)3028 static inline void membarrier_switch_mm(struct rq *rq,
3029 					struct mm_struct *prev_mm,
3030 					struct mm_struct *next_mm)
3031 {
3032 }
3033 #endif
3034 
3035 #ifdef CONFIG_SMP
is_per_cpu_kthread(struct task_struct * p)3036 static inline bool is_per_cpu_kthread(struct task_struct *p)
3037 {
3038 	if (!(p->flags & PF_KTHREAD))
3039 		return false;
3040 
3041 	if (p->nr_cpus_allowed != 1)
3042 		return false;
3043 
3044 	return true;
3045 }
3046 #endif
3047 
3048 extern void swake_up_all_locked(struct swait_queue_head *q);
3049 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
3050 
3051 #ifdef CONFIG_PREEMPT_DYNAMIC
3052 extern int preempt_dynamic_mode;
3053 extern int sched_dynamic_mode(const char *str);
3054 extern void sched_dynamic_update(int mode);
3055 #endif
3056 
3057