]> git.proxmox.com Git - mirror_ubuntu-hirsute-kernel.git/blob - kernel/sched/sched.h
UBUNTU: Ubuntu-5.11.0-22.23
[mirror_ubuntu-hirsute-kernel.git] / kernel / sched / sched.h
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/blkdev.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/rcupdate_wait.h>
61 #include <linux/security.h>
62 #include <linux/stop_machine.h>
63 #include <linux/suspend.h>
64 #include <linux/swait.h>
65 #include <linux/syscalls.h>
66 #include <linux/task_work.h>
67 #include <linux/tsacct_kern.h>
68
69 #include <asm/tlb.h>
70
71 #ifdef CONFIG_PARAVIRT
72 # include <asm/paravirt.h>
73 #endif
74
75 #include "cpupri.h"
76 #include "cpudeadline.h"
77
78 #include <trace/events/sched.h>
79
80 #ifdef CONFIG_SCHED_DEBUG
81 # define SCHED_WARN_ON(x) WARN_ONCE(x, #x)
82 #else
83 # define SCHED_WARN_ON(x) ({ (void)(x), 0; })
84 #endif
85
86 struct rq;
87 struct cpuidle_state;
88
89 /* task_struct::on_rq states: */
90 #define TASK_ON_RQ_QUEUED 1
91 #define TASK_ON_RQ_MIGRATING 2
92
93 extern __read_mostly int scheduler_running;
94
95 extern unsigned long calc_load_update;
96 extern atomic_long_t calc_load_tasks;
97
98 extern void calc_global_load_tick(struct rq *this_rq);
99 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
100
101 extern void call_trace_sched_update_nr_running(struct rq *rq, int count);
102 /*
103 * Helpers for converting nanosecond timing to jiffy resolution
104 */
105 #define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
106
107 /*
108 * Increase resolution of nice-level calculations for 64-bit architectures.
109 * The extra resolution improves shares distribution and load balancing of
110 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
111 * hierarchies, especially on larger systems. This is not a user-visible change
112 * and does not change the user-interface for setting shares/weights.
113 *
114 * We increase resolution only if we have enough bits to allow this increased
115 * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
116 * are pretty high and the returns do not justify the increased costs.
117 *
118 * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
119 * increase coverage and consistency always enable it on 64-bit platforms.
120 */
121 #ifdef CONFIG_64BIT
122 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
123 # define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT)
124 # define scale_load_down(w) \
125 ({ \
126 unsigned long __w = (w); \
127 if (__w) \
128 __w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \
129 __w; \
130 })
131 #else
132 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT)
133 # define scale_load(w) (w)
134 # define scale_load_down(w) (w)
135 #endif
136
137 /*
138 * Task weight (visible to users) and its load (invisible to users) have
139 * independent resolution, but they should be well calibrated. We use
140 * scale_load() and scale_load_down(w) to convert between them. The
141 * following must be true:
142 *
143 * scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD
144 *
145 */
146 #define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT)
147
148 /*
149 * Single value that decides SCHED_DEADLINE internal math precision.
150 * 10 -> just above 1us
151 * 9 -> just above 0.5us
152 */
153 #define DL_SCALE 10
154
155 /*
156 * Single value that denotes runtime == period, ie unlimited time.
157 */
158 #define RUNTIME_INF ((u64)~0ULL)
159
160 static inline int idle_policy(int policy)
161 {
162 return policy == SCHED_IDLE;
163 }
164 static inline int fair_policy(int policy)
165 {
166 return policy == SCHED_NORMAL || policy == SCHED_BATCH;
167 }
168
169 static inline int rt_policy(int policy)
170 {
171 return policy == SCHED_FIFO || policy == SCHED_RR;
172 }
173
174 static inline int dl_policy(int policy)
175 {
176 return policy == SCHED_DEADLINE;
177 }
178 static inline bool valid_policy(int policy)
179 {
180 return idle_policy(policy) || fair_policy(policy) ||
181 rt_policy(policy) || dl_policy(policy);
182 }
183
184 static inline int task_has_idle_policy(struct task_struct *p)
185 {
186 return idle_policy(p->policy);
187 }
188
189 static inline int task_has_rt_policy(struct task_struct *p)
190 {
191 return rt_policy(p->policy);
192 }
193
194 static inline int task_has_dl_policy(struct task_struct *p)
195 {
196 return dl_policy(p->policy);
197 }
198
199 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
200
201 static inline void update_avg(u64 *avg, u64 sample)
202 {
203 s64 diff = sample - *avg;
204 *avg += diff / 8;
205 }
206
207 /*
208 * Shifting a value by an exponent greater *or equal* to the size of said value
209 * is UB; cap at size-1.
210 */
211 #define shr_bound(val, shift) \
212 (val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1))
213
214 /*
215 * !! For sched_setattr_nocheck() (kernel) only !!
216 *
217 * This is actually gross. :(
218 *
219 * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
220 * tasks, but still be able to sleep. We need this on platforms that cannot
221 * atomically change clock frequency. Remove once fast switching will be
222 * available on such platforms.
223 *
224 * SUGOV stands for SchedUtil GOVernor.
225 */
226 #define SCHED_FLAG_SUGOV 0x10000000
227
228 static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se)
229 {
230 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
231 return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
232 #else
233 return false;
234 #endif
235 }
236
237 /*
238 * Tells if entity @a should preempt entity @b.
239 */
240 static inline bool
241 dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
242 {
243 return dl_entity_is_special(a) ||
244 dl_time_before(a->deadline, b->deadline);
245 }
246
247 /*
248 * This is the priority-queue data structure of the RT scheduling class:
249 */
250 struct rt_prio_array {
251 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
252 struct list_head queue[MAX_RT_PRIO];
253 };
254
255 struct rt_bandwidth {
256 /* nests inside the rq lock: */
257 raw_spinlock_t rt_runtime_lock;
258 ktime_t rt_period;
259 u64 rt_runtime;
260 struct hrtimer rt_period_timer;
261 unsigned int rt_period_active;
262 };
263
264 void __dl_clear_params(struct task_struct *p);
265
266 struct dl_bandwidth {
267 raw_spinlock_t dl_runtime_lock;
268 u64 dl_runtime;
269 u64 dl_period;
270 };
271
272 static inline int dl_bandwidth_enabled(void)
273 {
274 return sysctl_sched_rt_runtime >= 0;
275 }
276
277 /*
278 * To keep the bandwidth of -deadline tasks under control
279 * we need some place where:
280 * - store the maximum -deadline bandwidth of each cpu;
281 * - cache the fraction of bandwidth that is currently allocated in
282 * each root domain;
283 *
284 * This is all done in the data structure below. It is similar to the
285 * one used for RT-throttling (rt_bandwidth), with the main difference
286 * that, since here we are only interested in admission control, we
287 * do not decrease any runtime while the group "executes", neither we
288 * need a timer to replenish it.
289 *
290 * With respect to SMP, bandwidth is given on a per root domain basis,
291 * meaning that:
292 * - bw (< 100%) is the deadline bandwidth of each CPU;
293 * - total_bw is the currently allocated bandwidth in each root domain;
294 */
295 struct dl_bw {
296 raw_spinlock_t lock;
297 u64 bw;
298 u64 total_bw;
299 };
300
301 static inline void __dl_update(struct dl_bw *dl_b, s64 bw);
302
303 static inline
304 void __dl_sub(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
305 {
306 dl_b->total_bw -= tsk_bw;
307 __dl_update(dl_b, (s32)tsk_bw / cpus);
308 }
309
310 static inline
311 void __dl_add(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
312 {
313 dl_b->total_bw += tsk_bw;
314 __dl_update(dl_b, -((s32)tsk_bw / cpus));
315 }
316
317 static inline bool __dl_overflow(struct dl_bw *dl_b, unsigned long cap,
318 u64 old_bw, u64 new_bw)
319 {
320 return dl_b->bw != -1 &&
321 cap_scale(dl_b->bw, cap) < dl_b->total_bw - old_bw + new_bw;
322 }
323
324 /*
325 * Verify the fitness of task @p to run on @cpu taking into account the
326 * CPU original capacity and the runtime/deadline ratio of the task.
327 *
328 * The function will return true if the CPU original capacity of the
329 * @cpu scaled by SCHED_CAPACITY_SCALE >= runtime/deadline ratio of the
330 * task and false otherwise.
331 */
332 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
333 {
334 unsigned long cap = arch_scale_cpu_capacity(cpu);
335
336 return cap_scale(p->dl.dl_deadline, cap) >= p->dl.dl_runtime;
337 }
338
339 extern void init_dl_bw(struct dl_bw *dl_b);
340 extern int sched_dl_global_validate(void);
341 extern void sched_dl_do_global(void);
342 extern int sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
343 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
344 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
345 extern bool __checkparam_dl(const struct sched_attr *attr);
346 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
347 extern int dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
348 extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
349 extern bool dl_cpu_busy(unsigned int cpu);
350
351 #ifdef CONFIG_CGROUP_SCHED
352
353 #include <linux/cgroup.h>
354 #include <linux/psi.h>
355
356 struct cfs_rq;
357 struct rt_rq;
358
359 extern struct list_head task_groups;
360
361 struct cfs_bandwidth {
362 #ifdef CONFIG_CFS_BANDWIDTH
363 raw_spinlock_t lock;
364 ktime_t period;
365 u64 quota;
366 u64 runtime;
367 s64 hierarchical_quota;
368
369 u8 idle;
370 u8 period_active;
371 u8 slack_started;
372 struct hrtimer period_timer;
373 struct hrtimer slack_timer;
374 struct list_head throttled_cfs_rq;
375
376 /* Statistics: */
377 int nr_periods;
378 int nr_throttled;
379 u64 throttled_time;
380 #endif
381 };
382
383 /* Task group related information */
384 struct task_group {
385 struct cgroup_subsys_state css;
386
387 #ifdef CONFIG_FAIR_GROUP_SCHED
388 /* schedulable entities of this group on each CPU */
389 struct sched_entity **se;
390 /* runqueue "owned" by this group on each CPU */
391 struct cfs_rq **cfs_rq;
392 unsigned long shares;
393
394 #ifdef CONFIG_SMP
395 /*
396 * load_avg can be heavily contended at clock tick time, so put
397 * it in its own cacheline separated from the fields above which
398 * will also be accessed at each tick.
399 */
400 atomic_long_t load_avg ____cacheline_aligned;
401 #endif
402 #endif
403
404 #ifdef CONFIG_RT_GROUP_SCHED
405 struct sched_rt_entity **rt_se;
406 struct rt_rq **rt_rq;
407
408 struct rt_bandwidth rt_bandwidth;
409 #endif
410
411 struct rcu_head rcu;
412 struct list_head list;
413
414 struct task_group *parent;
415 struct list_head siblings;
416 struct list_head children;
417
418 #ifdef CONFIG_SCHED_AUTOGROUP
419 struct autogroup *autogroup;
420 #endif
421
422 struct cfs_bandwidth cfs_bandwidth;
423
424 #ifdef CONFIG_UCLAMP_TASK_GROUP
425 /* The two decimal precision [%] value requested from user-space */
426 unsigned int uclamp_pct[UCLAMP_CNT];
427 /* Clamp values requested for a task group */
428 struct uclamp_se uclamp_req[UCLAMP_CNT];
429 /* Effective clamp values used for a task group */
430 struct uclamp_se uclamp[UCLAMP_CNT];
431 #endif
432
433 };
434
435 #ifdef CONFIG_FAIR_GROUP_SCHED
436 #define ROOT_TASK_GROUP_LOAD NICE_0_LOAD
437
438 /*
439 * A weight of 0 or 1 can cause arithmetics problems.
440 * A weight of a cfs_rq is the sum of weights of which entities
441 * are queued on this cfs_rq, so a weight of a entity should not be
442 * too large, so as the shares value of a task group.
443 * (The default weight is 1024 - so there's no practical
444 * limitation from this.)
445 */
446 #define MIN_SHARES (1UL << 1)
447 #define MAX_SHARES (1UL << 18)
448 #endif
449
450 typedef int (*tg_visitor)(struct task_group *, void *);
451
452 extern int walk_tg_tree_from(struct task_group *from,
453 tg_visitor down, tg_visitor up, void *data);
454
455 /*
456 * Iterate the full tree, calling @down when first entering a node and @up when
457 * leaving it for the final time.
458 *
459 * Caller must hold rcu_lock or sufficient equivalent.
460 */
461 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
462 {
463 return walk_tg_tree_from(&root_task_group, down, up, data);
464 }
465
466 extern int tg_nop(struct task_group *tg, void *data);
467
468 extern void free_fair_sched_group(struct task_group *tg);
469 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
470 extern void online_fair_sched_group(struct task_group *tg);
471 extern void unregister_fair_sched_group(struct task_group *tg);
472 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
473 struct sched_entity *se, int cpu,
474 struct sched_entity *parent);
475 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
476
477 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
478 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
479 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
480
481 extern void free_rt_sched_group(struct task_group *tg);
482 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
483 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
484 struct sched_rt_entity *rt_se, int cpu,
485 struct sched_rt_entity *parent);
486 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
487 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
488 extern long sched_group_rt_runtime(struct task_group *tg);
489 extern long sched_group_rt_period(struct task_group *tg);
490 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
491
492 extern struct task_group *sched_create_group(struct task_group *parent);
493 extern void sched_online_group(struct task_group *tg,
494 struct task_group *parent);
495 extern void sched_destroy_group(struct task_group *tg);
496 extern void sched_offline_group(struct task_group *tg);
497
498 extern void sched_move_task(struct task_struct *tsk);
499
500 #ifdef CONFIG_FAIR_GROUP_SCHED
501 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
502
503 #ifdef CONFIG_SMP
504 extern void set_task_rq_fair(struct sched_entity *se,
505 struct cfs_rq *prev, struct cfs_rq *next);
506 #else /* !CONFIG_SMP */
507 static inline void set_task_rq_fair(struct sched_entity *se,
508 struct cfs_rq *prev, struct cfs_rq *next) { }
509 #endif /* CONFIG_SMP */
510 #endif /* CONFIG_FAIR_GROUP_SCHED */
511
512 #else /* CONFIG_CGROUP_SCHED */
513
514 struct cfs_bandwidth { };
515
516 #endif /* CONFIG_CGROUP_SCHED */
517
518 /* CFS-related fields in a runqueue */
519 struct cfs_rq {
520 struct load_weight load;
521 unsigned int nr_running;
522 unsigned int h_nr_running; /* SCHED_{NORMAL,BATCH,IDLE} */
523 unsigned int idle_h_nr_running; /* SCHED_IDLE */
524
525 u64 exec_clock;
526 u64 min_vruntime;
527 #ifndef CONFIG_64BIT
528 u64 min_vruntime_copy;
529 #endif
530
531 struct rb_root_cached tasks_timeline;
532
533 /*
534 * 'curr' points to currently running entity on this cfs_rq.
535 * It is set to NULL otherwise (i.e when none are currently running).
536 */
537 struct sched_entity *curr;
538 struct sched_entity *next;
539 struct sched_entity *last;
540 struct sched_entity *skip;
541
542 #ifdef CONFIG_SCHED_DEBUG
543 unsigned int nr_spread_over;
544 #endif
545
546 #ifdef CONFIG_SMP
547 /*
548 * CFS load tracking
549 */
550 struct sched_avg avg;
551 #ifndef CONFIG_64BIT
552 u64 load_last_update_time_copy;
553 #endif
554 struct {
555 raw_spinlock_t lock ____cacheline_aligned;
556 int nr;
557 unsigned long load_avg;
558 unsigned long util_avg;
559 unsigned long runnable_avg;
560 } removed;
561
562 #ifdef CONFIG_FAIR_GROUP_SCHED
563 unsigned long tg_load_avg_contrib;
564 long propagate;
565 long prop_runnable_sum;
566
567 /*
568 * h_load = weight * f(tg)
569 *
570 * Where f(tg) is the recursive weight fraction assigned to
571 * this group.
572 */
573 unsigned long h_load;
574 u64 last_h_load_update;
575 struct sched_entity *h_load_next;
576 #endif /* CONFIG_FAIR_GROUP_SCHED */
577 #endif /* CONFIG_SMP */
578
579 #ifdef CONFIG_FAIR_GROUP_SCHED
580 struct rq *rq; /* CPU runqueue to which this cfs_rq is attached */
581
582 /*
583 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
584 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
585 * (like users, containers etc.)
586 *
587 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
588 * This list is used during load balance.
589 */
590 int on_list;
591 struct list_head leaf_cfs_rq_list;
592 struct task_group *tg; /* group that "owns" this runqueue */
593
594 #ifdef CONFIG_CFS_BANDWIDTH
595 int runtime_enabled;
596 s64 runtime_remaining;
597
598 u64 throttled_clock;
599 u64 throttled_clock_task;
600 u64 throttled_clock_task_time;
601 int throttled;
602 int throttle_count;
603 struct list_head throttled_list;
604 #endif /* CONFIG_CFS_BANDWIDTH */
605 #endif /* CONFIG_FAIR_GROUP_SCHED */
606 };
607
608 static inline int rt_bandwidth_enabled(void)
609 {
610 return sysctl_sched_rt_runtime >= 0;
611 }
612
613 /* RT IPI pull logic requires IRQ_WORK */
614 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
615 # define HAVE_RT_PUSH_IPI
616 #endif
617
618 /* Real-Time classes' related field in a runqueue: */
619 struct rt_rq {
620 struct rt_prio_array active;
621 unsigned int rt_nr_running;
622 unsigned int rr_nr_running;
623 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
624 struct {
625 int curr; /* highest queued rt task prio */
626 #ifdef CONFIG_SMP
627 int next; /* next highest */
628 #endif
629 } highest_prio;
630 #endif
631 #ifdef CONFIG_SMP
632 unsigned long rt_nr_migratory;
633 unsigned long rt_nr_total;
634 int overloaded;
635 struct plist_head pushable_tasks;
636
637 #endif /* CONFIG_SMP */
638 int rt_queued;
639
640 int rt_throttled;
641 u64 rt_time;
642 u64 rt_runtime;
643 /* Nests inside the rq lock: */
644 raw_spinlock_t rt_runtime_lock;
645
646 #ifdef CONFIG_RT_GROUP_SCHED
647 unsigned long rt_nr_boosted;
648
649 struct rq *rq;
650 struct task_group *tg;
651 #endif
652 };
653
654 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
655 {
656 return rt_rq->rt_queued && rt_rq->rt_nr_running;
657 }
658
659 /* Deadline class' related fields in a runqueue */
660 struct dl_rq {
661 /* runqueue is an rbtree, ordered by deadline */
662 struct rb_root_cached root;
663
664 unsigned long dl_nr_running;
665
666 #ifdef CONFIG_SMP
667 /*
668 * Deadline values of the currently executing and the
669 * earliest ready task on this rq. Caching these facilitates
670 * the decision whether or not a ready but not running task
671 * should migrate somewhere else.
672 */
673 struct {
674 u64 curr;
675 u64 next;
676 } earliest_dl;
677
678 unsigned long dl_nr_migratory;
679 int overloaded;
680
681 /*
682 * Tasks on this rq that can be pushed away. They are kept in
683 * an rb-tree, ordered by tasks' deadlines, with caching
684 * of the leftmost (earliest deadline) element.
685 */
686 struct rb_root_cached pushable_dl_tasks_root;
687 #else
688 struct dl_bw dl_bw;
689 #endif
690 /*
691 * "Active utilization" for this runqueue: increased when a
692 * task wakes up (becomes TASK_RUNNING) and decreased when a
693 * task blocks
694 */
695 u64 running_bw;
696
697 /*
698 * Utilization of the tasks "assigned" to this runqueue (including
699 * the tasks that are in runqueue and the tasks that executed on this
700 * CPU and blocked). Increased when a task moves to this runqueue, and
701 * decreased when the task moves away (migrates, changes scheduling
702 * policy, or terminates).
703 * This is needed to compute the "inactive utilization" for the
704 * runqueue (inactive utilization = this_bw - running_bw).
705 */
706 u64 this_bw;
707 u64 extra_bw;
708
709 /*
710 * Inverse of the fraction of CPU utilization that can be reclaimed
711 * by the GRUB algorithm.
712 */
713 u64 bw_ratio;
714 };
715
716 #ifdef CONFIG_FAIR_GROUP_SCHED
717 /* An entity is a task if it doesn't "own" a runqueue */
718 #define entity_is_task(se) (!se->my_q)
719
720 static inline void se_update_runnable(struct sched_entity *se)
721 {
722 if (!entity_is_task(se))
723 se->runnable_weight = se->my_q->h_nr_running;
724 }
725
726 static inline long se_runnable(struct sched_entity *se)
727 {
728 if (entity_is_task(se))
729 return !!se->on_rq;
730 else
731 return se->runnable_weight;
732 }
733
734 #else
735 #define entity_is_task(se) 1
736
737 static inline void se_update_runnable(struct sched_entity *se) {}
738
739 static inline long se_runnable(struct sched_entity *se)
740 {
741 return !!se->on_rq;
742 }
743 #endif
744
745 #ifdef CONFIG_SMP
746 /*
747 * XXX we want to get rid of these helpers and use the full load resolution.
748 */
749 static inline long se_weight(struct sched_entity *se)
750 {
751 return scale_load_down(se->load.weight);
752 }
753
754
755 static inline bool sched_asym_prefer(int a, int b)
756 {
757 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
758 }
759
760 struct perf_domain {
761 struct em_perf_domain *em_pd;
762 struct perf_domain *next;
763 struct rcu_head rcu;
764 };
765
766 /* Scheduling group status flags */
767 #define SG_OVERLOAD 0x1 /* More than one runnable task on a CPU. */
768 #define SG_OVERUTILIZED 0x2 /* One or more CPUs are over-utilized. */
769
770 /*
771 * We add the notion of a root-domain which will be used to define per-domain
772 * variables. Each exclusive cpuset essentially defines an island domain by
773 * fully partitioning the member CPUs from any other cpuset. Whenever a new
774 * exclusive cpuset is created, we also create and attach a new root-domain
775 * object.
776 *
777 */
778 struct root_domain {
779 atomic_t refcount;
780 atomic_t rto_count;
781 struct rcu_head rcu;
782 cpumask_var_t span;
783 cpumask_var_t online;
784
785 /*
786 * Indicate pullable load on at least one CPU, e.g:
787 * - More than one runnable task
788 * - Running task is misfit
789 */
790 int overload;
791
792 /* Indicate one or more cpus over-utilized (tipping point) */
793 int overutilized;
794
795 /*
796 * The bit corresponding to a CPU gets set here if such CPU has more
797 * than one runnable -deadline task (as it is below for RT tasks).
798 */
799 cpumask_var_t dlo_mask;
800 atomic_t dlo_count;
801 struct dl_bw dl_bw;
802 struct cpudl cpudl;
803
804 /*
805 * Indicate whether a root_domain's dl_bw has been checked or
806 * updated. It's monotonously increasing value.
807 *
808 * Also, some corner cases, like 'wrap around' is dangerous, but given
809 * that u64 is 'big enough'. So that shouldn't be a concern.
810 */
811 u64 visit_gen;
812
813 #ifdef HAVE_RT_PUSH_IPI
814 /*
815 * For IPI pull requests, loop across the rto_mask.
816 */
817 struct irq_work rto_push_work;
818 raw_spinlock_t rto_lock;
819 /* These are only updated and read within rto_lock */
820 int rto_loop;
821 int rto_cpu;
822 /* These atomics are updated outside of a lock */
823 atomic_t rto_loop_next;
824 atomic_t rto_loop_start;
825 #endif
826 /*
827 * The "RT overload" flag: it gets set if a CPU has more than
828 * one runnable RT task.
829 */
830 cpumask_var_t rto_mask;
831 struct cpupri cpupri;
832
833 unsigned long max_cpu_capacity;
834
835 /*
836 * NULL-terminated list of performance domains intersecting with the
837 * CPUs of the rd. Protected by RCU.
838 */
839 struct perf_domain __rcu *pd;
840 };
841
842 extern void init_defrootdomain(void);
843 extern int sched_init_domains(const struct cpumask *cpu_map);
844 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
845 extern void sched_get_rd(struct root_domain *rd);
846 extern void sched_put_rd(struct root_domain *rd);
847
848 #ifdef HAVE_RT_PUSH_IPI
849 extern void rto_push_irq_work_func(struct irq_work *work);
850 #endif
851 #endif /* CONFIG_SMP */
852
853 #ifdef CONFIG_UCLAMP_TASK
854 /*
855 * struct uclamp_bucket - Utilization clamp bucket
856 * @value: utilization clamp value for tasks on this clamp bucket
857 * @tasks: number of RUNNABLE tasks on this clamp bucket
858 *
859 * Keep track of how many tasks are RUNNABLE for a given utilization
860 * clamp value.
861 */
862 struct uclamp_bucket {
863 unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
864 unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
865 };
866
867 /*
868 * struct uclamp_rq - rq's utilization clamp
869 * @value: currently active clamp values for a rq
870 * @bucket: utilization clamp buckets affecting a rq
871 *
872 * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
873 * A clamp value is affecting a rq when there is at least one task RUNNABLE
874 * (or actually running) with that value.
875 *
876 * There are up to UCLAMP_CNT possible different clamp values, currently there
877 * are only two: minimum utilization and maximum utilization.
878 *
879 * All utilization clamping values are MAX aggregated, since:
880 * - for util_min: we want to run the CPU at least at the max of the minimum
881 * utilization required by its currently RUNNABLE tasks.
882 * - for util_max: we want to allow the CPU to run up to the max of the
883 * maximum utilization allowed by its currently RUNNABLE tasks.
884 *
885 * Since on each system we expect only a limited number of different
886 * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
887 * the metrics required to compute all the per-rq utilization clamp values.
888 */
889 struct uclamp_rq {
890 unsigned int value;
891 struct uclamp_bucket bucket[UCLAMP_BUCKETS];
892 };
893
894 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
895 #endif /* CONFIG_UCLAMP_TASK */
896
897 /*
898 * This is the main, per-CPU runqueue data structure.
899 *
900 * Locking rule: those places that want to lock multiple runqueues
901 * (such as the load balancing or the thread migration code), lock
902 * acquire operations must be ordered by ascending &runqueue.
903 */
904 struct rq {
905 /* runqueue lock: */
906 raw_spinlock_t lock;
907
908 /*
909 * nr_running and cpu_load should be in the same cacheline because
910 * remote CPUs use both these fields when doing load calculation.
911 */
912 unsigned int nr_running;
913 #ifdef CONFIG_NUMA_BALANCING
914 unsigned int nr_numa_running;
915 unsigned int nr_preferred_running;
916 unsigned int numa_migrate_on;
917 #endif
918 #ifdef CONFIG_NO_HZ_COMMON
919 #ifdef CONFIG_SMP
920 unsigned long last_blocked_load_update_tick;
921 unsigned int has_blocked_load;
922 call_single_data_t nohz_csd;
923 #endif /* CONFIG_SMP */
924 unsigned int nohz_tick_stopped;
925 atomic_t nohz_flags;
926 #endif /* CONFIG_NO_HZ_COMMON */
927
928 #ifdef CONFIG_SMP
929 unsigned int ttwu_pending;
930 #endif
931 u64 nr_switches;
932
933 #ifdef CONFIG_UCLAMP_TASK
934 /* Utilization clamp values based on CPU's RUNNABLE tasks */
935 struct uclamp_rq uclamp[UCLAMP_CNT] ____cacheline_aligned;
936 unsigned int uclamp_flags;
937 #define UCLAMP_FLAG_IDLE 0x01
938 #endif
939
940 struct cfs_rq cfs;
941 struct rt_rq rt;
942 struct dl_rq dl;
943
944 #ifdef CONFIG_FAIR_GROUP_SCHED
945 /* list of leaf cfs_rq on this CPU: */
946 struct list_head leaf_cfs_rq_list;
947 struct list_head *tmp_alone_branch;
948 #endif /* CONFIG_FAIR_GROUP_SCHED */
949
950 /*
951 * This is part of a global counter where only the total sum
952 * over all CPUs matters. A task can increase this counter on
953 * one CPU and if it got migrated afterwards it may decrease
954 * it on another CPU. Always updated under the runqueue lock:
955 */
956 unsigned long nr_uninterruptible;
957
958 struct task_struct __rcu *curr;
959 struct task_struct *idle;
960 struct task_struct *stop;
961 unsigned long next_balance;
962 struct mm_struct *prev_mm;
963
964 unsigned int clock_update_flags;
965 u64 clock;
966 /* Ensure that all clocks are in the same cache line */
967 u64 clock_task ____cacheline_aligned;
968 u64 clock_pelt;
969 unsigned long lost_idle_time;
970
971 atomic_t nr_iowait;
972
973 #ifdef CONFIG_MEMBARRIER
974 int membarrier_state;
975 #endif
976
977 #ifdef CONFIG_SMP
978 struct root_domain *rd;
979 struct sched_domain __rcu *sd;
980
981 unsigned long cpu_capacity;
982 unsigned long cpu_capacity_orig;
983
984 struct callback_head *balance_callback;
985 unsigned char balance_push;
986
987 unsigned char nohz_idle_balance;
988 unsigned char idle_balance;
989
990 unsigned long misfit_task_load;
991
992 /* For active balancing */
993 int active_balance;
994 int push_cpu;
995 struct cpu_stop_work active_balance_work;
996
997 /* CPU of this runqueue: */
998 int cpu;
999 int online;
1000
1001 struct list_head cfs_tasks;
1002
1003 struct sched_avg avg_rt;
1004 struct sched_avg avg_dl;
1005 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1006 struct sched_avg avg_irq;
1007 #endif
1008 #ifdef CONFIG_SCHED_THERMAL_PRESSURE
1009 struct sched_avg avg_thermal;
1010 #endif
1011 u64 idle_stamp;
1012 u64 avg_idle;
1013
1014 /* This is used to determine avg_idle's max value */
1015 u64 max_idle_balance_cost;
1016
1017 #ifdef CONFIG_HOTPLUG_CPU
1018 struct rcuwait hotplug_wait;
1019 #endif
1020 #endif /* CONFIG_SMP */
1021
1022 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1023 u64 prev_irq_time;
1024 #endif
1025 #ifdef CONFIG_PARAVIRT
1026 u64 prev_steal_time;
1027 #endif
1028 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1029 u64 prev_steal_time_rq;
1030 #endif
1031
1032 /* calc_load related fields */
1033 unsigned long calc_load_update;
1034 long calc_load_active;
1035
1036 #ifdef CONFIG_SCHED_HRTICK
1037 #ifdef CONFIG_SMP
1038 call_single_data_t hrtick_csd;
1039 #endif
1040 struct hrtimer hrtick_timer;
1041 ktime_t hrtick_time;
1042 #endif
1043
1044 #ifdef CONFIG_SCHEDSTATS
1045 /* latency stats */
1046 struct sched_info rq_sched_info;
1047 unsigned long long rq_cpu_time;
1048 /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
1049
1050 /* sys_sched_yield() stats */
1051 unsigned int yld_count;
1052
1053 /* schedule() stats */
1054 unsigned int sched_count;
1055 unsigned int sched_goidle;
1056
1057 /* try_to_wake_up() stats */
1058 unsigned int ttwu_count;
1059 unsigned int ttwu_local;
1060 #endif
1061
1062 #ifdef CONFIG_CPU_IDLE
1063 /* Must be inspected within a rcu lock section */
1064 struct cpuidle_state *idle_state;
1065 #endif
1066
1067 #ifdef CONFIG_SMP
1068 unsigned int nr_pinned;
1069 #endif
1070 unsigned int push_busy;
1071 struct cpu_stop_work push_work;
1072 };
1073
1074 #ifdef CONFIG_FAIR_GROUP_SCHED
1075
1076 /* CPU runqueue to which this cfs_rq is attached */
1077 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1078 {
1079 return cfs_rq->rq;
1080 }
1081
1082 #else
1083
1084 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1085 {
1086 return container_of(cfs_rq, struct rq, cfs);
1087 }
1088 #endif
1089
1090 static inline int cpu_of(struct rq *rq)
1091 {
1092 #ifdef CONFIG_SMP
1093 return rq->cpu;
1094 #else
1095 return 0;
1096 #endif
1097 }
1098
1099 #define MDF_PUSH 0x01
1100
1101 static inline bool is_migration_disabled(struct task_struct *p)
1102 {
1103 #ifdef CONFIG_SMP
1104 return p->migration_disabled;
1105 #else
1106 return false;
1107 #endif
1108 }
1109
1110 #ifdef CONFIG_SCHED_SMT
1111 extern void __update_idle_core(struct rq *rq);
1112
1113 static inline void update_idle_core(struct rq *rq)
1114 {
1115 if (static_branch_unlikely(&sched_smt_present))
1116 __update_idle_core(rq);
1117 }
1118
1119 #else
1120 static inline void update_idle_core(struct rq *rq) { }
1121 #endif
1122
1123 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1124
1125 #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
1126 #define this_rq() this_cpu_ptr(&runqueues)
1127 #define task_rq(p) cpu_rq(task_cpu(p))
1128 #define cpu_curr(cpu) (cpu_rq(cpu)->curr)
1129 #define raw_rq() raw_cpu_ptr(&runqueues)
1130
1131 extern void update_rq_clock(struct rq *rq);
1132
1133 static inline u64 __rq_clock_broken(struct rq *rq)
1134 {
1135 return READ_ONCE(rq->clock);
1136 }
1137
1138 /*
1139 * rq::clock_update_flags bits
1140 *
1141 * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1142 * call to __schedule(). This is an optimisation to avoid
1143 * neighbouring rq clock updates.
1144 *
1145 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1146 * in effect and calls to update_rq_clock() are being ignored.
1147 *
1148 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1149 * made to update_rq_clock() since the last time rq::lock was pinned.
1150 *
1151 * If inside of __schedule(), clock_update_flags will have been
1152 * shifted left (a left shift is a cheap operation for the fast path
1153 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1154 *
1155 * if (rq-clock_update_flags >= RQCF_UPDATED)
1156 *
1157 * to check if %RQCF_UPADTED is set. It'll never be shifted more than
1158 * one position though, because the next rq_unpin_lock() will shift it
1159 * back.
1160 */
1161 #define RQCF_REQ_SKIP 0x01
1162 #define RQCF_ACT_SKIP 0x02
1163 #define RQCF_UPDATED 0x04
1164
1165 static inline void assert_clock_updated(struct rq *rq)
1166 {
1167 /*
1168 * The only reason for not seeing a clock update since the
1169 * last rq_pin_lock() is if we're currently skipping updates.
1170 */
1171 SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
1172 }
1173
1174 static inline u64 rq_clock(struct rq *rq)
1175 {
1176 lockdep_assert_held(&rq->lock);
1177 assert_clock_updated(rq);
1178
1179 return rq->clock;
1180 }
1181
1182 static inline u64 rq_clock_task(struct rq *rq)
1183 {
1184 lockdep_assert_held(&rq->lock);
1185 assert_clock_updated(rq);
1186
1187 return rq->clock_task;
1188 }
1189
1190 /**
1191 * By default the decay is the default pelt decay period.
1192 * The decay shift can change the decay period in
1193 * multiples of 32.
1194 * Decay shift Decay period(ms)
1195 * 0 32
1196 * 1 64
1197 * 2 128
1198 * 3 256
1199 * 4 512
1200 */
1201 extern int sched_thermal_decay_shift;
1202
1203 static inline u64 rq_clock_thermal(struct rq *rq)
1204 {
1205 return rq_clock_task(rq) >> sched_thermal_decay_shift;
1206 }
1207
1208 static inline void rq_clock_skip_update(struct rq *rq)
1209 {
1210 lockdep_assert_held(&rq->lock);
1211 rq->clock_update_flags |= RQCF_REQ_SKIP;
1212 }
1213
1214 /*
1215 * See rt task throttling, which is the only time a skip
1216 * request is cancelled.
1217 */
1218 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1219 {
1220 lockdep_assert_held(&rq->lock);
1221 rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1222 }
1223
1224 struct rq_flags {
1225 unsigned long flags;
1226 struct pin_cookie cookie;
1227 #ifdef CONFIG_SCHED_DEBUG
1228 /*
1229 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1230 * current pin context is stashed here in case it needs to be
1231 * restored in rq_repin_lock().
1232 */
1233 unsigned int clock_update_flags;
1234 #endif
1235 };
1236
1237 extern struct callback_head balance_push_callback;
1238
1239 /*
1240 * Lockdep annotation that avoids accidental unlocks; it's like a
1241 * sticky/continuous lockdep_assert_held().
1242 *
1243 * This avoids code that has access to 'struct rq *rq' (basically everything in
1244 * the scheduler) from accidentally unlocking the rq if they do not also have a
1245 * copy of the (on-stack) 'struct rq_flags rf'.
1246 *
1247 * Also see Documentation/locking/lockdep-design.rst.
1248 */
1249 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1250 {
1251 rf->cookie = lockdep_pin_lock(&rq->lock);
1252
1253 #ifdef CONFIG_SCHED_DEBUG
1254 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1255 rf->clock_update_flags = 0;
1256 #ifdef CONFIG_SMP
1257 SCHED_WARN_ON(rq->balance_callback && rq->balance_callback != &balance_push_callback);
1258 #endif
1259 #endif
1260 }
1261
1262 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1263 {
1264 #ifdef CONFIG_SCHED_DEBUG
1265 if (rq->clock_update_flags > RQCF_ACT_SKIP)
1266 rf->clock_update_flags = RQCF_UPDATED;
1267 #endif
1268
1269 lockdep_unpin_lock(&rq->lock, rf->cookie);
1270 }
1271
1272 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1273 {
1274 lockdep_repin_lock(&rq->lock, rf->cookie);
1275
1276 #ifdef CONFIG_SCHED_DEBUG
1277 /*
1278 * Restore the value we stashed in @rf for this pin context.
1279 */
1280 rq->clock_update_flags |= rf->clock_update_flags;
1281 #endif
1282 }
1283
1284 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1285 __acquires(rq->lock);
1286
1287 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1288 __acquires(p->pi_lock)
1289 __acquires(rq->lock);
1290
1291 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1292 __releases(rq->lock)
1293 {
1294 rq_unpin_lock(rq, rf);
1295 raw_spin_unlock(&rq->lock);
1296 }
1297
1298 static inline void
1299 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1300 __releases(rq->lock)
1301 __releases(p->pi_lock)
1302 {
1303 rq_unpin_lock(rq, rf);
1304 raw_spin_unlock(&rq->lock);
1305 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1306 }
1307
1308 static inline void
1309 rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1310 __acquires(rq->lock)
1311 {
1312 raw_spin_lock_irqsave(&rq->lock, rf->flags);
1313 rq_pin_lock(rq, rf);
1314 }
1315
1316 static inline void
1317 rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1318 __acquires(rq->lock)
1319 {
1320 raw_spin_lock_irq(&rq->lock);
1321 rq_pin_lock(rq, rf);
1322 }
1323
1324 static inline void
1325 rq_lock(struct rq *rq, struct rq_flags *rf)
1326 __acquires(rq->lock)
1327 {
1328 raw_spin_lock(&rq->lock);
1329 rq_pin_lock(rq, rf);
1330 }
1331
1332 static inline void
1333 rq_relock(struct rq *rq, struct rq_flags *rf)
1334 __acquires(rq->lock)
1335 {
1336 raw_spin_lock(&rq->lock);
1337 rq_repin_lock(rq, rf);
1338 }
1339
1340 static inline void
1341 rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1342 __releases(rq->lock)
1343 {
1344 rq_unpin_lock(rq, rf);
1345 raw_spin_unlock_irqrestore(&rq->lock, rf->flags);
1346 }
1347
1348 static inline void
1349 rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1350 __releases(rq->lock)
1351 {
1352 rq_unpin_lock(rq, rf);
1353 raw_spin_unlock_irq(&rq->lock);
1354 }
1355
1356 static inline void
1357 rq_unlock(struct rq *rq, struct rq_flags *rf)
1358 __releases(rq->lock)
1359 {
1360 rq_unpin_lock(rq, rf);
1361 raw_spin_unlock(&rq->lock);
1362 }
1363
1364 static inline struct rq *
1365 this_rq_lock_irq(struct rq_flags *rf)
1366 __acquires(rq->lock)
1367 {
1368 struct rq *rq;
1369
1370 local_irq_disable();
1371 rq = this_rq();
1372 rq_lock(rq, rf);
1373 return rq;
1374 }
1375
1376 #ifdef CONFIG_NUMA
1377 enum numa_topology_type {
1378 NUMA_DIRECT,
1379 NUMA_GLUELESS_MESH,
1380 NUMA_BACKPLANE,
1381 };
1382 extern enum numa_topology_type sched_numa_topology_type;
1383 extern int sched_max_numa_distance;
1384 extern bool find_numa_distance(int distance);
1385 extern void sched_init_numa(void);
1386 extern void sched_domains_numa_masks_set(unsigned int cpu);
1387 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1388 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1389 #else
1390 static inline void sched_init_numa(void) { }
1391 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
1392 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1393 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1394 {
1395 return nr_cpu_ids;
1396 }
1397 #endif
1398
1399 #ifdef CONFIG_NUMA_BALANCING
1400 /* The regions in numa_faults array from task_struct */
1401 enum numa_faults_stats {
1402 NUMA_MEM = 0,
1403 NUMA_CPU,
1404 NUMA_MEMBUF,
1405 NUMA_CPUBUF
1406 };
1407 extern void sched_setnuma(struct task_struct *p, int node);
1408 extern int migrate_task_to(struct task_struct *p, int cpu);
1409 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1410 int cpu, int scpu);
1411 extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1412 #else
1413 static inline void
1414 init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1415 {
1416 }
1417 #endif /* CONFIG_NUMA_BALANCING */
1418
1419 #ifdef CONFIG_SMP
1420
1421 static inline void
1422 queue_balance_callback(struct rq *rq,
1423 struct callback_head *head,
1424 void (*func)(struct rq *rq))
1425 {
1426 lockdep_assert_held(&rq->lock);
1427
1428 if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
1429 return;
1430
1431 head->func = (void (*)(struct callback_head *))func;
1432 head->next = rq->balance_callback;
1433 rq->balance_callback = head;
1434 }
1435
1436 #define rcu_dereference_check_sched_domain(p) \
1437 rcu_dereference_check((p), \
1438 lockdep_is_held(&sched_domains_mutex))
1439
1440 /*
1441 * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1442 * See destroy_sched_domains: call_rcu for details.
1443 *
1444 * The domain tree of any CPU may only be accessed from within
1445 * preempt-disabled sections.
1446 */
1447 #define for_each_domain(cpu, __sd) \
1448 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1449 __sd; __sd = __sd->parent)
1450
1451 /**
1452 * highest_flag_domain - Return highest sched_domain containing flag.
1453 * @cpu: The CPU whose highest level of sched domain is to
1454 * be returned.
1455 * @flag: The flag to check for the highest sched_domain
1456 * for the given CPU.
1457 *
1458 * Returns the highest sched_domain of a CPU which contains the given flag.
1459 */
1460 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1461 {
1462 struct sched_domain *sd, *hsd = NULL;
1463
1464 for_each_domain(cpu, sd) {
1465 if (!(sd->flags & flag))
1466 break;
1467 hsd = sd;
1468 }
1469
1470 return hsd;
1471 }
1472
1473 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1474 {
1475 struct sched_domain *sd;
1476
1477 for_each_domain(cpu, sd) {
1478 if (sd->flags & flag)
1479 break;
1480 }
1481
1482 return sd;
1483 }
1484
1485 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
1486 DECLARE_PER_CPU(int, sd_llc_size);
1487 DECLARE_PER_CPU(int, sd_llc_id);
1488 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
1489 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
1490 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
1491 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
1492 extern struct static_key_false sched_asym_cpucapacity;
1493
1494 struct sched_group_capacity {
1495 atomic_t ref;
1496 /*
1497 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
1498 * for a single CPU.
1499 */
1500 unsigned long capacity;
1501 unsigned long min_capacity; /* Min per-CPU capacity in group */
1502 unsigned long max_capacity; /* Max per-CPU capacity in group */
1503 unsigned long next_update;
1504 int imbalance; /* XXX unrelated to capacity but shared group state */
1505
1506 #ifdef CONFIG_SCHED_DEBUG
1507 int id;
1508 #endif
1509
1510 unsigned long cpumask[]; /* Balance mask */
1511 };
1512
1513 struct sched_group {
1514 struct sched_group *next; /* Must be a circular list */
1515 atomic_t ref;
1516
1517 unsigned int group_weight;
1518 struct sched_group_capacity *sgc;
1519 int asym_prefer_cpu; /* CPU of highest priority in group */
1520
1521 /*
1522 * The CPUs this group covers.
1523 *
1524 * NOTE: this field is variable length. (Allocated dynamically
1525 * by attaching extra space to the end of the structure,
1526 * depending on how many CPUs the kernel has booted up with)
1527 */
1528 unsigned long cpumask[];
1529 };
1530
1531 static inline struct cpumask *sched_group_span(struct sched_group *sg)
1532 {
1533 return to_cpumask(sg->cpumask);
1534 }
1535
1536 /*
1537 * See build_balance_mask().
1538 */
1539 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
1540 {
1541 return to_cpumask(sg->sgc->cpumask);
1542 }
1543
1544 /**
1545 * group_first_cpu - Returns the first CPU in the cpumask of a sched_group.
1546 * @group: The group whose first CPU is to be returned.
1547 */
1548 static inline unsigned int group_first_cpu(struct sched_group *group)
1549 {
1550 return cpumask_first(sched_group_span(group));
1551 }
1552
1553 extern int group_balance_cpu(struct sched_group *sg);
1554
1555 #if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
1556 void register_sched_domain_sysctl(void);
1557 void dirty_sched_domain_sysctl(int cpu);
1558 void unregister_sched_domain_sysctl(void);
1559 #else
1560 static inline void register_sched_domain_sysctl(void)
1561 {
1562 }
1563 static inline void dirty_sched_domain_sysctl(int cpu)
1564 {
1565 }
1566 static inline void unregister_sched_domain_sysctl(void)
1567 {
1568 }
1569 #endif
1570
1571 extern void flush_smp_call_function_from_idle(void);
1572
1573 #else /* !CONFIG_SMP: */
1574 static inline void flush_smp_call_function_from_idle(void) { }
1575 #endif
1576
1577 #include "stats.h"
1578 #include "autogroup.h"
1579
1580 #ifdef CONFIG_CGROUP_SCHED
1581
1582 /*
1583 * Return the group to which this tasks belongs.
1584 *
1585 * We cannot use task_css() and friends because the cgroup subsystem
1586 * changes that value before the cgroup_subsys::attach() method is called,
1587 * therefore we cannot pin it and might observe the wrong value.
1588 *
1589 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
1590 * core changes this before calling sched_move_task().
1591 *
1592 * Instead we use a 'copy' which is updated from sched_move_task() while
1593 * holding both task_struct::pi_lock and rq::lock.
1594 */
1595 static inline struct task_group *task_group(struct task_struct *p)
1596 {
1597 return p->sched_task_group;
1598 }
1599
1600 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
1601 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
1602 {
1603 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
1604 struct task_group *tg = task_group(p);
1605 #endif
1606
1607 #ifdef CONFIG_FAIR_GROUP_SCHED
1608 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
1609 p->se.cfs_rq = tg->cfs_rq[cpu];
1610 p->se.parent = tg->se[cpu];
1611 #endif
1612
1613 #ifdef CONFIG_RT_GROUP_SCHED
1614 p->rt.rt_rq = tg->rt_rq[cpu];
1615 p->rt.parent = tg->rt_se[cpu];
1616 #endif
1617 }
1618
1619 #else /* CONFIG_CGROUP_SCHED */
1620
1621 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
1622 static inline struct task_group *task_group(struct task_struct *p)
1623 {
1624 return NULL;
1625 }
1626
1627 #endif /* CONFIG_CGROUP_SCHED */
1628
1629 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
1630 {
1631 set_task_rq(p, cpu);
1632 #ifdef CONFIG_SMP
1633 /*
1634 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
1635 * successfully executed on another CPU. We must ensure that updates of
1636 * per-task data have been completed by this moment.
1637 */
1638 smp_wmb();
1639 #ifdef CONFIG_THREAD_INFO_IN_TASK
1640 WRITE_ONCE(p->cpu, cpu);
1641 #else
1642 WRITE_ONCE(task_thread_info(p)->cpu, cpu);
1643 #endif
1644 p->wake_cpu = cpu;
1645 #endif
1646 }
1647
1648 /*
1649 * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
1650 */
1651 #ifdef CONFIG_SCHED_DEBUG
1652 # include <linux/static_key.h>
1653 # define const_debug __read_mostly
1654 #else
1655 # define const_debug const
1656 #endif
1657
1658 #define SCHED_FEAT(name, enabled) \
1659 __SCHED_FEAT_##name ,
1660
1661 enum {
1662 #include "features.h"
1663 __SCHED_FEAT_NR,
1664 };
1665
1666 #undef SCHED_FEAT
1667
1668 #ifdef CONFIG_SCHED_DEBUG
1669
1670 /*
1671 * To support run-time toggling of sched features, all the translation units
1672 * (but core.c) reference the sysctl_sched_features defined in core.c.
1673 */
1674 extern const_debug unsigned int sysctl_sched_features;
1675
1676 #ifdef CONFIG_JUMP_LABEL
1677 #define SCHED_FEAT(name, enabled) \
1678 static __always_inline bool static_branch_##name(struct static_key *key) \
1679 { \
1680 return static_key_##enabled(key); \
1681 }
1682
1683 #include "features.h"
1684 #undef SCHED_FEAT
1685
1686 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
1687 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
1688
1689 #else /* !CONFIG_JUMP_LABEL */
1690
1691 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1692
1693 #endif /* CONFIG_JUMP_LABEL */
1694
1695 #else /* !SCHED_DEBUG */
1696
1697 /*
1698 * Each translation unit has its own copy of sysctl_sched_features to allow
1699 * constants propagation at compile time and compiler optimization based on
1700 * features default.
1701 */
1702 #define SCHED_FEAT(name, enabled) \
1703 (1UL << __SCHED_FEAT_##name) * enabled |
1704 static const_debug __maybe_unused unsigned int sysctl_sched_features =
1705 #include "features.h"
1706 0;
1707 #undef SCHED_FEAT
1708
1709 #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1710
1711 #endif /* SCHED_DEBUG */
1712
1713 extern struct static_key_false sched_numa_balancing;
1714 extern struct static_key_false sched_schedstats;
1715
1716 static inline u64 global_rt_period(void)
1717 {
1718 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
1719 }
1720
1721 static inline u64 global_rt_runtime(void)
1722 {
1723 if (sysctl_sched_rt_runtime < 0)
1724 return RUNTIME_INF;
1725
1726 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
1727 }
1728
1729 static inline int task_current(struct rq *rq, struct task_struct *p)
1730 {
1731 return rq->curr == p;
1732 }
1733
1734 static inline int task_running(struct rq *rq, struct task_struct *p)
1735 {
1736 #ifdef CONFIG_SMP
1737 return p->on_cpu;
1738 #else
1739 return task_current(rq, p);
1740 #endif
1741 }
1742
1743 static inline int task_on_rq_queued(struct task_struct *p)
1744 {
1745 return p->on_rq == TASK_ON_RQ_QUEUED;
1746 }
1747
1748 static inline int task_on_rq_migrating(struct task_struct *p)
1749 {
1750 return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
1751 }
1752
1753 /* Wake flags. The first three directly map to some SD flag value */
1754 #define WF_EXEC 0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
1755 #define WF_FORK 0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
1756 #define WF_TTWU 0x08 /* Wakeup; maps to SD_BALANCE_WAKE */
1757
1758 #define WF_SYNC 0x10 /* Waker goes to sleep after wakeup */
1759 #define WF_MIGRATED 0x20 /* Internal use, task got migrated */
1760 #define WF_ON_CPU 0x40 /* Wakee is on_cpu */
1761
1762 #ifdef CONFIG_SMP
1763 static_assert(WF_EXEC == SD_BALANCE_EXEC);
1764 static_assert(WF_FORK == SD_BALANCE_FORK);
1765 static_assert(WF_TTWU == SD_BALANCE_WAKE);
1766 #endif
1767
1768 /*
1769 * To aid in avoiding the subversion of "niceness" due to uneven distribution
1770 * of tasks with abnormal "nice" values across CPUs the contribution that
1771 * each task makes to its run queue's load is weighted according to its
1772 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
1773 * scaled version of the new time slice allocation that they receive on time
1774 * slice expiry etc.
1775 */
1776
1777 #define WEIGHT_IDLEPRIO 3
1778 #define WMULT_IDLEPRIO 1431655765
1779
1780 extern const int sched_prio_to_weight[40];
1781 extern const u32 sched_prio_to_wmult[40];
1782
1783 /*
1784 * {de,en}queue flags:
1785 *
1786 * DEQUEUE_SLEEP - task is no longer runnable
1787 * ENQUEUE_WAKEUP - task just became runnable
1788 *
1789 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
1790 * are in a known state which allows modification. Such pairs
1791 * should preserve as much state as possible.
1792 *
1793 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
1794 * in the runqueue.
1795 *
1796 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified)
1797 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
1798 * ENQUEUE_MIGRATED - the task was migrated during wakeup
1799 *
1800 */
1801
1802 #define DEQUEUE_SLEEP 0x01
1803 #define DEQUEUE_SAVE 0x02 /* Matches ENQUEUE_RESTORE */
1804 #define DEQUEUE_MOVE 0x04 /* Matches ENQUEUE_MOVE */
1805 #define DEQUEUE_NOCLOCK 0x08 /* Matches ENQUEUE_NOCLOCK */
1806
1807 #define ENQUEUE_WAKEUP 0x01
1808 #define ENQUEUE_RESTORE 0x02
1809 #define ENQUEUE_MOVE 0x04
1810 #define ENQUEUE_NOCLOCK 0x08
1811
1812 #define ENQUEUE_HEAD 0x10
1813 #define ENQUEUE_REPLENISH 0x20
1814 #ifdef CONFIG_SMP
1815 #define ENQUEUE_MIGRATED 0x40
1816 #else
1817 #define ENQUEUE_MIGRATED 0x00
1818 #endif
1819
1820 #define RETRY_TASK ((void *)-1UL)
1821
1822 struct sched_class {
1823
1824 #ifdef CONFIG_UCLAMP_TASK
1825 int uclamp_enabled;
1826 #endif
1827
1828 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1829 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1830 void (*yield_task) (struct rq *rq);
1831 bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
1832
1833 void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags);
1834
1835 struct task_struct *(*pick_next_task)(struct rq *rq);
1836
1837 void (*put_prev_task)(struct rq *rq, struct task_struct *p);
1838 void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
1839
1840 #ifdef CONFIG_SMP
1841 int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
1842 int (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
1843 void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
1844
1845 void (*task_woken)(struct rq *this_rq, struct task_struct *task);
1846
1847 void (*set_cpus_allowed)(struct task_struct *p,
1848 const struct cpumask *newmask,
1849 u32 flags);
1850
1851 void (*rq_online)(struct rq *rq);
1852 void (*rq_offline)(struct rq *rq);
1853
1854 struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
1855 #endif
1856
1857 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
1858 void (*task_fork)(struct task_struct *p);
1859 void (*task_dead)(struct task_struct *p);
1860
1861 /*
1862 * The switched_from() call is allowed to drop rq->lock, therefore we
1863 * cannot assume the switched_from/switched_to pair is serliazed by
1864 * rq->lock. They are however serialized by p->pi_lock.
1865 */
1866 void (*switched_from)(struct rq *this_rq, struct task_struct *task);
1867 void (*switched_to) (struct rq *this_rq, struct task_struct *task);
1868 void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1869 int oldprio);
1870
1871 unsigned int (*get_rr_interval)(struct rq *rq,
1872 struct task_struct *task);
1873
1874 void (*update_curr)(struct rq *rq);
1875
1876 #define TASK_SET_GROUP 0
1877 #define TASK_MOVE_GROUP 1
1878
1879 #ifdef CONFIG_FAIR_GROUP_SCHED
1880 void (*task_change_group)(struct task_struct *p, int type);
1881 #endif
1882 };
1883
1884 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
1885 {
1886 WARN_ON_ONCE(rq->curr != prev);
1887 prev->sched_class->put_prev_task(rq, prev);
1888 }
1889
1890 static inline void set_next_task(struct rq *rq, struct task_struct *next)
1891 {
1892 WARN_ON_ONCE(rq->curr != next);
1893 next->sched_class->set_next_task(rq, next, false);
1894 }
1895
1896
1897 /*
1898 * Helper to define a sched_class instance; each one is placed in a separate
1899 * section which is ordered by the linker script:
1900 *
1901 * include/asm-generic/vmlinux.lds.h
1902 *
1903 * Also enforce alignment on the instance, not the type, to guarantee layout.
1904 */
1905 #define DEFINE_SCHED_CLASS(name) \
1906 const struct sched_class name##_sched_class \
1907 __aligned(__alignof__(struct sched_class)) \
1908 __section("__" #name "_sched_class")
1909
1910 /* Defined in include/asm-generic/vmlinux.lds.h */
1911 extern struct sched_class __begin_sched_classes[];
1912 extern struct sched_class __end_sched_classes[];
1913
1914 #define sched_class_highest (__end_sched_classes - 1)
1915 #define sched_class_lowest (__begin_sched_classes - 1)
1916
1917 #define for_class_range(class, _from, _to) \
1918 for (class = (_from); class != (_to); class--)
1919
1920 #define for_each_class(class) \
1921 for_class_range(class, sched_class_highest, sched_class_lowest)
1922
1923 extern const struct sched_class stop_sched_class;
1924 extern const struct sched_class dl_sched_class;
1925 extern const struct sched_class rt_sched_class;
1926 extern const struct sched_class fair_sched_class;
1927 extern const struct sched_class idle_sched_class;
1928
1929 static inline bool sched_stop_runnable(struct rq *rq)
1930 {
1931 return rq->stop && task_on_rq_queued(rq->stop);
1932 }
1933
1934 static inline bool sched_dl_runnable(struct rq *rq)
1935 {
1936 return rq->dl.dl_nr_running > 0;
1937 }
1938
1939 static inline bool sched_rt_runnable(struct rq *rq)
1940 {
1941 return rq->rt.rt_queued > 0;
1942 }
1943
1944 static inline bool sched_fair_runnable(struct rq *rq)
1945 {
1946 return rq->cfs.nr_running > 0;
1947 }
1948
1949 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
1950 extern struct task_struct *pick_next_task_idle(struct rq *rq);
1951
1952 #define SCA_CHECK 0x01
1953 #define SCA_MIGRATE_DISABLE 0x02
1954 #define SCA_MIGRATE_ENABLE 0x04
1955
1956 #ifdef CONFIG_SMP
1957
1958 extern void update_group_capacity(struct sched_domain *sd, int cpu);
1959
1960 extern void trigger_load_balance(struct rq *rq);
1961
1962 extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask, u32 flags);
1963
1964 static inline struct task_struct *get_push_task(struct rq *rq)
1965 {
1966 struct task_struct *p = rq->curr;
1967
1968 lockdep_assert_held(&rq->lock);
1969
1970 if (rq->push_busy)
1971 return NULL;
1972
1973 if (p->nr_cpus_allowed == 1)
1974 return NULL;
1975
1976 rq->push_busy = true;
1977 return get_task_struct(p);
1978 }
1979
1980 extern int push_cpu_stop(void *arg);
1981
1982 #endif
1983
1984 #ifdef CONFIG_CPU_IDLE
1985 static inline void idle_set_state(struct rq *rq,
1986 struct cpuidle_state *idle_state)
1987 {
1988 rq->idle_state = idle_state;
1989 }
1990
1991 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1992 {
1993 SCHED_WARN_ON(!rcu_read_lock_held());
1994
1995 return rq->idle_state;
1996 }
1997 #else
1998 static inline void idle_set_state(struct rq *rq,
1999 struct cpuidle_state *idle_state)
2000 {
2001 }
2002
2003 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2004 {
2005 return NULL;
2006 }
2007 #endif
2008
2009 extern void schedule_idle(void);
2010
2011 extern void sysrq_sched_debug_show(void);
2012 extern void sched_init_granularity(void);
2013 extern void update_max_interval(void);
2014
2015 extern void init_sched_dl_class(void);
2016 extern void init_sched_rt_class(void);
2017 extern void init_sched_fair_class(void);
2018
2019 extern void reweight_task(struct task_struct *p, int prio);
2020
2021 extern void resched_curr(struct rq *rq);
2022 extern void resched_cpu(int cpu);
2023
2024 extern struct rt_bandwidth def_rt_bandwidth;
2025 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
2026
2027 extern struct dl_bandwidth def_dl_bandwidth;
2028 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
2029 extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
2030 extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se);
2031
2032 #define BW_SHIFT 20
2033 #define BW_UNIT (1 << BW_SHIFT)
2034 #define RATIO_SHIFT 8
2035 #define MAX_BW_BITS (64 - BW_SHIFT)
2036 #define MAX_BW ((1ULL << MAX_BW_BITS) - 1)
2037 unsigned long to_ratio(u64 period, u64 runtime);
2038
2039 extern void init_entity_runnable_average(struct sched_entity *se);
2040 extern void post_init_entity_util_avg(struct task_struct *p);
2041
2042 #ifdef CONFIG_NO_HZ_FULL
2043 extern bool sched_can_stop_tick(struct rq *rq);
2044 extern int __init sched_tick_offload_init(void);
2045
2046 /*
2047 * Tick may be needed by tasks in the runqueue depending on their policy and
2048 * requirements. If tick is needed, lets send the target an IPI to kick it out of
2049 * nohz mode if necessary.
2050 */
2051 static inline void sched_update_tick_dependency(struct rq *rq)
2052 {
2053 int cpu = cpu_of(rq);
2054
2055 if (!tick_nohz_full_cpu(cpu))
2056 return;
2057
2058 if (sched_can_stop_tick(rq))
2059 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
2060 else
2061 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
2062 }
2063 #else
2064 static inline int sched_tick_offload_init(void) { return 0; }
2065 static inline void sched_update_tick_dependency(struct rq *rq) { }
2066 #endif
2067
2068 static inline void add_nr_running(struct rq *rq, unsigned count)
2069 {
2070 unsigned prev_nr = rq->nr_running;
2071
2072 rq->nr_running = prev_nr + count;
2073 if (trace_sched_update_nr_running_tp_enabled()) {
2074 call_trace_sched_update_nr_running(rq, count);
2075 }
2076
2077 #ifdef CONFIG_SMP
2078 if (prev_nr < 2 && rq->nr_running >= 2) {
2079 if (!READ_ONCE(rq->rd->overload))
2080 WRITE_ONCE(rq->rd->overload, 1);
2081 }
2082 #endif
2083
2084 sched_update_tick_dependency(rq);
2085 }
2086
2087 static inline void sub_nr_running(struct rq *rq, unsigned count)
2088 {
2089 rq->nr_running -= count;
2090 if (trace_sched_update_nr_running_tp_enabled()) {
2091 call_trace_sched_update_nr_running(rq, -count);
2092 }
2093
2094 /* Check if we still need preemption */
2095 sched_update_tick_dependency(rq);
2096 }
2097
2098 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
2099 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
2100
2101 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
2102
2103 extern const_debug unsigned int sysctl_sched_nr_migrate;
2104 extern const_debug unsigned int sysctl_sched_migration_cost;
2105
2106 #ifdef CONFIG_SCHED_HRTICK
2107
2108 /*
2109 * Use hrtick when:
2110 * - enabled by features
2111 * - hrtimer is actually high res
2112 */
2113 static inline int hrtick_enabled(struct rq *rq)
2114 {
2115 if (!sched_feat(HRTICK))
2116 return 0;
2117 if (!cpu_active(cpu_of(rq)))
2118 return 0;
2119 return hrtimer_is_hres_active(&rq->hrtick_timer);
2120 }
2121
2122 void hrtick_start(struct rq *rq, u64 delay);
2123
2124 #else
2125
2126 static inline int hrtick_enabled(struct rq *rq)
2127 {
2128 return 0;
2129 }
2130
2131 #endif /* CONFIG_SCHED_HRTICK */
2132
2133 #ifndef arch_scale_freq_tick
2134 static __always_inline
2135 void arch_scale_freq_tick(void)
2136 {
2137 }
2138 #endif
2139
2140 #ifndef arch_scale_freq_capacity
2141 /**
2142 * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
2143 * @cpu: the CPU in question.
2144 *
2145 * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
2146 *
2147 * f_curr
2148 * ------ * SCHED_CAPACITY_SCALE
2149 * f_max
2150 */
2151 static __always_inline
2152 unsigned long arch_scale_freq_capacity(int cpu)
2153 {
2154 return SCHED_CAPACITY_SCALE;
2155 }
2156 #endif
2157
2158 #ifdef CONFIG_SMP
2159 #ifdef CONFIG_PREEMPTION
2160
2161 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2);
2162
2163 /*
2164 * fair double_lock_balance: Safely acquires both rq->locks in a fair
2165 * way at the expense of forcing extra atomic operations in all
2166 * invocations. This assures that the double_lock is acquired using the
2167 * same underlying policy as the spinlock_t on this architecture, which
2168 * reduces latency compared to the unfair variant below. However, it
2169 * also adds more overhead and therefore may reduce throughput.
2170 */
2171 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2172 __releases(this_rq->lock)
2173 __acquires(busiest->lock)
2174 __acquires(this_rq->lock)
2175 {
2176 raw_spin_unlock(&this_rq->lock);
2177 double_rq_lock(this_rq, busiest);
2178
2179 return 1;
2180 }
2181
2182 #else
2183 /*
2184 * Unfair double_lock_balance: Optimizes throughput at the expense of
2185 * latency by eliminating extra atomic operations when the locks are
2186 * already in proper order on entry. This favors lower CPU-ids and will
2187 * grant the double lock to lower CPUs over higher ids under contention,
2188 * regardless of entry order into the function.
2189 */
2190 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2191 __releases(this_rq->lock)
2192 __acquires(busiest->lock)
2193 __acquires(this_rq->lock)
2194 {
2195 int ret = 0;
2196
2197 if (unlikely(!raw_spin_trylock(&busiest->lock))) {
2198 if (busiest < this_rq) {
2199 raw_spin_unlock(&this_rq->lock);
2200 raw_spin_lock(&busiest->lock);
2201 raw_spin_lock_nested(&this_rq->lock,
2202 SINGLE_DEPTH_NESTING);
2203 ret = 1;
2204 } else
2205 raw_spin_lock_nested(&busiest->lock,
2206 SINGLE_DEPTH_NESTING);
2207 }
2208 return ret;
2209 }
2210
2211 #endif /* CONFIG_PREEMPTION */
2212
2213 /*
2214 * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
2215 */
2216 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
2217 {
2218 if (unlikely(!irqs_disabled())) {
2219 /* printk() doesn't work well under rq->lock */
2220 raw_spin_unlock(&this_rq->lock);
2221 BUG_ON(1);
2222 }
2223
2224 return _double_lock_balance(this_rq, busiest);
2225 }
2226
2227 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
2228 __releases(busiest->lock)
2229 {
2230 raw_spin_unlock(&busiest->lock);
2231 lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
2232 }
2233
2234 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
2235 {
2236 if (l1 > l2)
2237 swap(l1, l2);
2238
2239 spin_lock(l1);
2240 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2241 }
2242
2243 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
2244 {
2245 if (l1 > l2)
2246 swap(l1, l2);
2247
2248 spin_lock_irq(l1);
2249 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2250 }
2251
2252 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
2253 {
2254 if (l1 > l2)
2255 swap(l1, l2);
2256
2257 raw_spin_lock(l1);
2258 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2259 }
2260
2261 /*
2262 * double_rq_lock - safely lock two runqueues
2263 *
2264 * Note this does not disable interrupts like task_rq_lock,
2265 * you need to do so manually before calling.
2266 */
2267 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2268 __acquires(rq1->lock)
2269 __acquires(rq2->lock)
2270 {
2271 BUG_ON(!irqs_disabled());
2272 if (rq1 == rq2) {
2273 raw_spin_lock(&rq1->lock);
2274 __acquire(rq2->lock); /* Fake it out ;) */
2275 } else {
2276 if (rq1 < rq2) {
2277 raw_spin_lock(&rq1->lock);
2278 raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
2279 } else {
2280 raw_spin_lock(&rq2->lock);
2281 raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
2282 }
2283 }
2284 }
2285
2286 /*
2287 * double_rq_unlock - safely unlock two runqueues
2288 *
2289 * Note this does not restore interrupts like task_rq_unlock,
2290 * you need to do so manually after calling.
2291 */
2292 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2293 __releases(rq1->lock)
2294 __releases(rq2->lock)
2295 {
2296 raw_spin_unlock(&rq1->lock);
2297 if (rq1 != rq2)
2298 raw_spin_unlock(&rq2->lock);
2299 else
2300 __release(rq2->lock);
2301 }
2302
2303 extern void set_rq_online (struct rq *rq);
2304 extern void set_rq_offline(struct rq *rq);
2305 extern bool sched_smp_initialized;
2306
2307 #else /* CONFIG_SMP */
2308
2309 /*
2310 * double_rq_lock - safely lock two runqueues
2311 *
2312 * Note this does not disable interrupts like task_rq_lock,
2313 * you need to do so manually before calling.
2314 */
2315 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2316 __acquires(rq1->lock)
2317 __acquires(rq2->lock)
2318 {
2319 BUG_ON(!irqs_disabled());
2320 BUG_ON(rq1 != rq2);
2321 raw_spin_lock(&rq1->lock);
2322 __acquire(rq2->lock); /* Fake it out ;) */
2323 }
2324
2325 /*
2326 * double_rq_unlock - safely unlock two runqueues
2327 *
2328 * Note this does not restore interrupts like task_rq_unlock,
2329 * you need to do so manually after calling.
2330 */
2331 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2332 __releases(rq1->lock)
2333 __releases(rq2->lock)
2334 {
2335 BUG_ON(rq1 != rq2);
2336 raw_spin_unlock(&rq1->lock);
2337 __release(rq2->lock);
2338 }
2339
2340 #endif
2341
2342 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
2343 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
2344
2345 #ifdef CONFIG_SCHED_DEBUG
2346 extern bool sched_debug_enabled;
2347
2348 extern void print_cfs_stats(struct seq_file *m, int cpu);
2349 extern void print_rt_stats(struct seq_file *m, int cpu);
2350 extern void print_dl_stats(struct seq_file *m, int cpu);
2351 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
2352 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
2353 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
2354 #ifdef CONFIG_NUMA_BALANCING
2355 extern void
2356 show_numa_stats(struct task_struct *p, struct seq_file *m);
2357 extern void
2358 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
2359 unsigned long tpf, unsigned long gsf, unsigned long gpf);
2360 #endif /* CONFIG_NUMA_BALANCING */
2361 #endif /* CONFIG_SCHED_DEBUG */
2362
2363 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
2364 extern void init_rt_rq(struct rt_rq *rt_rq);
2365 extern void init_dl_rq(struct dl_rq *dl_rq);
2366
2367 extern void cfs_bandwidth_usage_inc(void);
2368 extern void cfs_bandwidth_usage_dec(void);
2369
2370 #ifdef CONFIG_NO_HZ_COMMON
2371 #define NOHZ_BALANCE_KICK_BIT 0
2372 #define NOHZ_STATS_KICK_BIT 1
2373
2374 #define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT)
2375 #define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT)
2376
2377 #define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK)
2378
2379 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
2380
2381 extern void nohz_balance_exit_idle(struct rq *rq);
2382 #else
2383 static inline void nohz_balance_exit_idle(struct rq *rq) { }
2384 #endif
2385
2386
2387 #ifdef CONFIG_SMP
2388 static inline
2389 void __dl_update(struct dl_bw *dl_b, s64 bw)
2390 {
2391 struct root_domain *rd = container_of(dl_b, struct root_domain, dl_bw);
2392 int i;
2393
2394 RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
2395 "sched RCU must be held");
2396 for_each_cpu_and(i, rd->span, cpu_active_mask) {
2397 struct rq *rq = cpu_rq(i);
2398
2399 rq->dl.extra_bw += bw;
2400 }
2401 }
2402 #else
2403 static inline
2404 void __dl_update(struct dl_bw *dl_b, s64 bw)
2405 {
2406 struct dl_rq *dl = container_of(dl_b, struct dl_rq, dl_bw);
2407
2408 dl->extra_bw += bw;
2409 }
2410 #endif
2411
2412
2413 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2414 struct irqtime {
2415 u64 total;
2416 u64 tick_delta;
2417 u64 irq_start_time;
2418 struct u64_stats_sync sync;
2419 };
2420
2421 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
2422
2423 /*
2424 * Returns the irqtime minus the softirq time computed by ksoftirqd.
2425 * Otherwise ksoftirqd's sum_exec_runtime is substracted its own runtime
2426 * and never move forward.
2427 */
2428 static inline u64 irq_time_read(int cpu)
2429 {
2430 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
2431 unsigned int seq;
2432 u64 total;
2433
2434 do {
2435 seq = __u64_stats_fetch_begin(&irqtime->sync);
2436 total = irqtime->total;
2437 } while (__u64_stats_fetch_retry(&irqtime->sync, seq));
2438
2439 return total;
2440 }
2441 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
2442
2443 #ifdef CONFIG_CPU_FREQ
2444 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
2445
2446 /**
2447 * cpufreq_update_util - Take a note about CPU utilization changes.
2448 * @rq: Runqueue to carry out the update for.
2449 * @flags: Update reason flags.
2450 *
2451 * This function is called by the scheduler on the CPU whose utilization is
2452 * being updated.
2453 *
2454 * It can only be called from RCU-sched read-side critical sections.
2455 *
2456 * The way cpufreq is currently arranged requires it to evaluate the CPU
2457 * performance state (frequency/voltage) on a regular basis to prevent it from
2458 * being stuck in a completely inadequate performance level for too long.
2459 * That is not guaranteed to happen if the updates are only triggered from CFS
2460 * and DL, though, because they may not be coming in if only RT tasks are
2461 * active all the time (or there are RT tasks only).
2462 *
2463 * As a workaround for that issue, this function is called periodically by the
2464 * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
2465 * but that really is a band-aid. Going forward it should be replaced with
2466 * solutions targeted more specifically at RT tasks.
2467 */
2468 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
2469 {
2470 struct update_util_data *data;
2471
2472 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
2473 cpu_of(rq)));
2474 if (data)
2475 data->func(data, rq_clock(rq), flags);
2476 }
2477 #else
2478 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
2479 #endif /* CONFIG_CPU_FREQ */
2480
2481 #ifdef CONFIG_UCLAMP_TASK
2482 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
2483
2484 /**
2485 * uclamp_rq_util_with - clamp @util with @rq and @p effective uclamp values.
2486 * @rq: The rq to clamp against. Must not be NULL.
2487 * @util: The util value to clamp.
2488 * @p: The task to clamp against. Can be NULL if you want to clamp
2489 * against @rq only.
2490 *
2491 * Clamps the passed @util to the max(@rq, @p) effective uclamp values.
2492 *
2493 * If sched_uclamp_used static key is disabled, then just return the util
2494 * without any clamping since uclamp aggregation at the rq level in the fast
2495 * path is disabled, rendering this operation a NOP.
2496 *
2497 * Use uclamp_eff_value() if you don't care about uclamp values at rq level. It
2498 * will return the correct effective uclamp value of the task even if the
2499 * static key is disabled.
2500 */
2501 static __always_inline
2502 unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
2503 struct task_struct *p)
2504 {
2505 unsigned long min_util;
2506 unsigned long max_util;
2507
2508 if (!static_branch_likely(&sched_uclamp_used))
2509 return util;
2510
2511 min_util = READ_ONCE(rq->uclamp[UCLAMP_MIN].value);
2512 max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
2513
2514 if (p) {
2515 min_util = max(min_util, uclamp_eff_value(p, UCLAMP_MIN));
2516 max_util = max(max_util, uclamp_eff_value(p, UCLAMP_MAX));
2517 }
2518
2519 /*
2520 * Since CPU's {min,max}_util clamps are MAX aggregated considering
2521 * RUNNABLE tasks with _different_ clamps, we can end up with an
2522 * inversion. Fix it now when the clamps are applied.
2523 */
2524 if (unlikely(min_util >= max_util))
2525 return min_util;
2526
2527 return clamp(util, min_util, max_util);
2528 }
2529
2530 /*
2531 * When uclamp is compiled in, the aggregation at rq level is 'turned off'
2532 * by default in the fast path and only gets turned on once userspace performs
2533 * an operation that requires it.
2534 *
2535 * Returns true if userspace opted-in to use uclamp and aggregation at rq level
2536 * hence is active.
2537 */
2538 static inline bool uclamp_is_used(void)
2539 {
2540 return static_branch_likely(&sched_uclamp_used);
2541 }
2542 #else /* CONFIG_UCLAMP_TASK */
2543 static inline
2544 unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
2545 struct task_struct *p)
2546 {
2547 return util;
2548 }
2549
2550 static inline bool uclamp_is_used(void)
2551 {
2552 return false;
2553 }
2554 #endif /* CONFIG_UCLAMP_TASK */
2555
2556 #ifdef arch_scale_freq_capacity
2557 # ifndef arch_scale_freq_invariant
2558 # define arch_scale_freq_invariant() true
2559 # endif
2560 #else
2561 # define arch_scale_freq_invariant() false
2562 #endif
2563
2564 #ifdef CONFIG_SMP
2565 static inline unsigned long capacity_orig_of(int cpu)
2566 {
2567 return cpu_rq(cpu)->cpu_capacity_orig;
2568 }
2569 #endif
2570
2571 /**
2572 * enum schedutil_type - CPU utilization type
2573 * @FREQUENCY_UTIL: Utilization used to select frequency
2574 * @ENERGY_UTIL: Utilization used during energy calculation
2575 *
2576 * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time
2577 * need to be aggregated differently depending on the usage made of them. This
2578 * enum is used within schedutil_freq_util() to differentiate the types of
2579 * utilization expected by the callers, and adjust the aggregation accordingly.
2580 */
2581 enum schedutil_type {
2582 FREQUENCY_UTIL,
2583 ENERGY_UTIL,
2584 };
2585
2586 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
2587
2588 unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
2589 unsigned long max, enum schedutil_type type,
2590 struct task_struct *p);
2591
2592 static inline unsigned long cpu_bw_dl(struct rq *rq)
2593 {
2594 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
2595 }
2596
2597 static inline unsigned long cpu_util_dl(struct rq *rq)
2598 {
2599 return READ_ONCE(rq->avg_dl.util_avg);
2600 }
2601
2602 static inline unsigned long cpu_util_cfs(struct rq *rq)
2603 {
2604 unsigned long util = READ_ONCE(rq->cfs.avg.util_avg);
2605
2606 if (sched_feat(UTIL_EST)) {
2607 util = max_t(unsigned long, util,
2608 READ_ONCE(rq->cfs.avg.util_est.enqueued));
2609 }
2610
2611 return util;
2612 }
2613
2614 static inline unsigned long cpu_util_rt(struct rq *rq)
2615 {
2616 return READ_ONCE(rq->avg_rt.util_avg);
2617 }
2618 #else /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
2619 static inline unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
2620 unsigned long max, enum schedutil_type type,
2621 struct task_struct *p)
2622 {
2623 return 0;
2624 }
2625 #endif /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
2626
2627 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
2628 static inline unsigned long cpu_util_irq(struct rq *rq)
2629 {
2630 return rq->avg_irq.util_avg;
2631 }
2632
2633 static inline
2634 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2635 {
2636 util *= (max - irq);
2637 util /= max;
2638
2639 return util;
2640
2641 }
2642 #else
2643 static inline unsigned long cpu_util_irq(struct rq *rq)
2644 {
2645 return 0;
2646 }
2647
2648 static inline
2649 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2650 {
2651 return util;
2652 }
2653 #endif
2654
2655 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
2656
2657 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
2658
2659 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
2660
2661 static inline bool sched_energy_enabled(void)
2662 {
2663 return static_branch_unlikely(&sched_energy_present);
2664 }
2665
2666 #else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
2667
2668 #define perf_domain_span(pd) NULL
2669 static inline bool sched_energy_enabled(void) { return false; }
2670
2671 #endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
2672
2673 #ifdef CONFIG_MEMBARRIER
2674 /*
2675 * The scheduler provides memory barriers required by membarrier between:
2676 * - prior user-space memory accesses and store to rq->membarrier_state,
2677 * - store to rq->membarrier_state and following user-space memory accesses.
2678 * In the same way it provides those guarantees around store to rq->curr.
2679 */
2680 static inline void membarrier_switch_mm(struct rq *rq,
2681 struct mm_struct *prev_mm,
2682 struct mm_struct *next_mm)
2683 {
2684 int membarrier_state;
2685
2686 if (prev_mm == next_mm)
2687 return;
2688
2689 membarrier_state = atomic_read(&next_mm->membarrier_state);
2690 if (READ_ONCE(rq->membarrier_state) == membarrier_state)
2691 return;
2692
2693 WRITE_ONCE(rq->membarrier_state, membarrier_state);
2694 }
2695 #else
2696 static inline void membarrier_switch_mm(struct rq *rq,
2697 struct mm_struct *prev_mm,
2698 struct mm_struct *next_mm)
2699 {
2700 }
2701 #endif
2702
2703 #ifdef CONFIG_SMP
2704 static inline bool is_per_cpu_kthread(struct task_struct *p)
2705 {
2706 if (!(p->flags & PF_KTHREAD))
2707 return false;
2708
2709 if (p->nr_cpus_allowed != 1)
2710 return false;
2711
2712 return true;
2713 }
2714 #endif
2715
2716 void swake_up_all_locked(struct swait_queue_head *q);
2717 void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);