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1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Scheduler internal types and methods:
4 */
5 #ifndef _KERNEL_SCHED_SCHED_H
6 #define _KERNEL_SCHED_SCHED_H
7
8 #include <linux/sched/affinity.h>
9 #include <linux/sched/autogroup.h>
10 #include <linux/sched/cpufreq.h>
11 #include <linux/sched/deadline.h>
12 #include <linux/sched.h>
13 #include <linux/sched/loadavg.h>
14 #include <linux/sched/mm.h>
15 #include <linux/sched/rseq_api.h>
16 #include <linux/sched/signal.h>
17 #include <linux/sched/smt.h>
18 #include <linux/sched/stat.h>
19 #include <linux/sched/sysctl.h>
20 #include <linux/sched/task_flags.h>
21 #include <linux/sched/task.h>
22 #include <linux/sched/topology.h>
23
24 #include <linux/atomic.h>
25 #include <linux/bitmap.h>
26 #include <linux/bug.h>
27 #include <linux/capability.h>
28 #include <linux/cgroup_api.h>
29 #include <linux/cgroup.h>
30 #include <linux/cpufreq.h>
31 #include <linux/cpumask_api.h>
32 #include <linux/ctype.h>
33 #include <linux/file.h>
34 #include <linux/fs_api.h>
35 #include <linux/hrtimer_api.h>
36 #include <linux/interrupt.h>
37 #include <linux/irq_work.h>
38 #include <linux/jiffies.h>
39 #include <linux/kref_api.h>
40 #include <linux/kthread.h>
41 #include <linux/ktime_api.h>
42 #include <linux/lockdep_api.h>
43 #include <linux/lockdep.h>
44 #include <linux/minmax.h>
45 #include <linux/mm.h>
46 #include <linux/module.h>
47 #include <linux/mutex_api.h>
48 #include <linux/plist.h>
49 #include <linux/poll.h>
50 #include <linux/proc_fs.h>
51 #include <linux/profile.h>
52 #include <linux/psi.h>
53 #include <linux/rcupdate.h>
54 #include <linux/seq_file.h>
55 #include <linux/seqlock.h>
56 #include <linux/softirq.h>
57 #include <linux/spinlock_api.h>
58 #include <linux/static_key.h>
59 #include <linux/stop_machine.h>
60 #include <linux/syscalls_api.h>
61 #include <linux/syscalls.h>
62 #include <linux/tick.h>
63 #include <linux/topology.h>
64 #include <linux/types.h>
65 #include <linux/u64_stats_sync_api.h>
66 #include <linux/uaccess.h>
67 #include <linux/wait_api.h>
68 #include <linux/wait_bit.h>
69 #include <linux/workqueue_api.h>
70
71 #include <trace/events/power.h>
72 #include <trace/events/sched.h>
73
74 #include "../workqueue_internal.h"
75
76 #ifdef CONFIG_CGROUP_SCHED
77 #include <linux/cgroup.h>
78 #include <linux/psi.h>
79 #endif
80
81 #ifdef CONFIG_SCHED_DEBUG
82 # include <linux/static_key.h>
83 #endif
84
85 #ifdef CONFIG_PARAVIRT
86 # include <asm/paravirt.h>
87 # include <asm/paravirt_api_clock.h>
88 #endif
89
90 #include "cpupri.h"
91 #include "cpudeadline.h"
92
93 #ifdef CONFIG_SCHED_DEBUG
94 # define SCHED_WARN_ON(x) WARN_ONCE(x, #x)
95 #else
96 # define SCHED_WARN_ON(x) ({ (void)(x), 0; })
97 #endif
98
99 struct rq;
100 struct cpuidle_state;
101
102 /* task_struct::on_rq states: */
103 #define TASK_ON_RQ_QUEUED 1
104 #define TASK_ON_RQ_MIGRATING 2
105
106 extern __read_mostly int scheduler_running;
107
108 extern unsigned long calc_load_update;
109 extern atomic_long_t calc_load_tasks;
110
111 extern void calc_global_load_tick(struct rq *this_rq);
112 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
113
114 extern void call_trace_sched_update_nr_running(struct rq *rq, int count);
115 /*
116 * Helpers for converting nanosecond timing to jiffy resolution
117 */
118 #define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
119
120 /*
121 * Increase resolution of nice-level calculations for 64-bit architectures.
122 * The extra resolution improves shares distribution and load balancing of
123 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
124 * hierarchies, especially on larger systems. This is not a user-visible change
125 * and does not change the user-interface for setting shares/weights.
126 *
127 * We increase resolution only if we have enough bits to allow this increased
128 * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
129 * are pretty high and the returns do not justify the increased costs.
130 *
131 * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
132 * increase coverage and consistency always enable it on 64-bit platforms.
133 */
134 #ifdef CONFIG_64BIT
135 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
136 # define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT)
137 # define scale_load_down(w) \
138 ({ \
139 unsigned long __w = (w); \
140 if (__w) \
141 __w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \
142 __w; \
143 })
144 #else
145 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT)
146 # define scale_load(w) (w)
147 # define scale_load_down(w) (w)
148 #endif
149
150 /*
151 * Task weight (visible to users) and its load (invisible to users) have
152 * independent resolution, but they should be well calibrated. We use
153 * scale_load() and scale_load_down(w) to convert between them. The
154 * following must be true:
155 *
156 * scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD
157 *
158 */
159 #define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT)
160
161 /*
162 * Single value that decides SCHED_DEADLINE internal math precision.
163 * 10 -> just above 1us
164 * 9 -> just above 0.5us
165 */
166 #define DL_SCALE 10
167
168 /*
169 * Single value that denotes runtime == period, ie unlimited time.
170 */
171 #define RUNTIME_INF ((u64)~0ULL)
172
173 static inline int idle_policy(int policy)
174 {
175 return policy == SCHED_IDLE;
176 }
177 static inline int fair_policy(int policy)
178 {
179 return policy == SCHED_NORMAL || policy == SCHED_BATCH;
180 }
181
182 static inline int rt_policy(int policy)
183 {
184 return policy == SCHED_FIFO || policy == SCHED_RR;
185 }
186
187 static inline int dl_policy(int policy)
188 {
189 return policy == SCHED_DEADLINE;
190 }
191 static inline bool valid_policy(int policy)
192 {
193 return idle_policy(policy) || fair_policy(policy) ||
194 rt_policy(policy) || dl_policy(policy);
195 }
196
197 static inline int task_has_idle_policy(struct task_struct *p)
198 {
199 return idle_policy(p->policy);
200 }
201
202 static inline int task_has_rt_policy(struct task_struct *p)
203 {
204 return rt_policy(p->policy);
205 }
206
207 static inline int task_has_dl_policy(struct task_struct *p)
208 {
209 return dl_policy(p->policy);
210 }
211
212 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
213
214 static inline void update_avg(u64 *avg, u64 sample)
215 {
216 s64 diff = sample - *avg;
217 *avg += diff / 8;
218 }
219
220 /*
221 * Shifting a value by an exponent greater *or equal* to the size of said value
222 * is UB; cap at size-1.
223 */
224 #define shr_bound(val, shift) \
225 (val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1))
226
227 /*
228 * !! For sched_setattr_nocheck() (kernel) only !!
229 *
230 * This is actually gross. :(
231 *
232 * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
233 * tasks, but still be able to sleep. We need this on platforms that cannot
234 * atomically change clock frequency. Remove once fast switching will be
235 * available on such platforms.
236 *
237 * SUGOV stands for SchedUtil GOVernor.
238 */
239 #define SCHED_FLAG_SUGOV 0x10000000
240
241 #define SCHED_DL_FLAGS (SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV)
242
243 static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se)
244 {
245 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
246 return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
247 #else
248 return false;
249 #endif
250 }
251
252 /*
253 * Tells if entity @a should preempt entity @b.
254 */
255 static inline bool
256 dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
257 {
258 return dl_entity_is_special(a) ||
259 dl_time_before(a->deadline, b->deadline);
260 }
261
262 /*
263 * This is the priority-queue data structure of the RT scheduling class:
264 */
265 struct rt_prio_array {
266 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
267 struct list_head queue[MAX_RT_PRIO];
268 };
269
270 struct rt_bandwidth {
271 /* nests inside the rq lock: */
272 raw_spinlock_t rt_runtime_lock;
273 ktime_t rt_period;
274 u64 rt_runtime;
275 struct hrtimer rt_period_timer;
276 unsigned int rt_period_active;
277 };
278
279 void __dl_clear_params(struct task_struct *p);
280
281 struct dl_bandwidth {
282 raw_spinlock_t dl_runtime_lock;
283 u64 dl_runtime;
284 u64 dl_period;
285 };
286
287 static inline int dl_bandwidth_enabled(void)
288 {
289 return sysctl_sched_rt_runtime >= 0;
290 }
291
292 /*
293 * To keep the bandwidth of -deadline tasks under control
294 * we need some place where:
295 * - store the maximum -deadline bandwidth of each cpu;
296 * - cache the fraction of bandwidth that is currently allocated in
297 * each root domain;
298 *
299 * This is all done in the data structure below. It is similar to the
300 * one used for RT-throttling (rt_bandwidth), with the main difference
301 * that, since here we are only interested in admission control, we
302 * do not decrease any runtime while the group "executes", neither we
303 * need a timer to replenish it.
304 *
305 * With respect to SMP, bandwidth is given on a per root domain basis,
306 * meaning that:
307 * - bw (< 100%) is the deadline bandwidth of each CPU;
308 * - total_bw is the currently allocated bandwidth in each root domain;
309 */
310 struct dl_bw {
311 raw_spinlock_t lock;
312 u64 bw;
313 u64 total_bw;
314 };
315
316 /*
317 * Verify the fitness of task @p to run on @cpu taking into account the
318 * CPU original capacity and the runtime/deadline ratio of the task.
319 *
320 * The function will return true if the CPU original capacity of the
321 * @cpu scaled by SCHED_CAPACITY_SCALE >= runtime/deadline ratio of the
322 * task and false otherwise.
323 */
324 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
325 {
326 unsigned long cap = arch_scale_cpu_capacity(cpu);
327
328 return cap_scale(p->dl.dl_deadline, cap) >= p->dl.dl_runtime;
329 }
330
331 extern void init_dl_bw(struct dl_bw *dl_b);
332 extern int sched_dl_global_validate(void);
333 extern void sched_dl_do_global(void);
334 extern int sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
335 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
336 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
337 extern bool __checkparam_dl(const struct sched_attr *attr);
338 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
339 extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
340 extern int dl_cpu_busy(int cpu, struct task_struct *p);
341
342 #ifdef CONFIG_CGROUP_SCHED
343
344 struct cfs_rq;
345 struct rt_rq;
346
347 extern struct list_head task_groups;
348
349 struct cfs_bandwidth {
350 #ifdef CONFIG_CFS_BANDWIDTH
351 raw_spinlock_t lock;
352 ktime_t period;
353 u64 quota;
354 u64 runtime;
355 u64 burst;
356 u64 runtime_snap;
357 s64 hierarchical_quota;
358
359 u8 idle;
360 u8 period_active;
361 u8 slack_started;
362 struct hrtimer period_timer;
363 struct hrtimer slack_timer;
364 struct list_head throttled_cfs_rq;
365
366 /* Statistics: */
367 int nr_periods;
368 int nr_throttled;
369 int nr_burst;
370 u64 throttled_time;
371 u64 burst_time;
372 #endif
373 };
374
375 /* Task group related information */
376 struct task_group {
377 struct cgroup_subsys_state css;
378
379 #ifdef CONFIG_FAIR_GROUP_SCHED
380 /* schedulable entities of this group on each CPU */
381 struct sched_entity **se;
382 /* runqueue "owned" by this group on each CPU */
383 struct cfs_rq **cfs_rq;
384 unsigned long shares;
385
386 /* A positive value indicates that this is a SCHED_IDLE group. */
387 int idle;
388
389 #ifdef CONFIG_SMP
390 /*
391 * load_avg can be heavily contended at clock tick time, so put
392 * it in its own cacheline separated from the fields above which
393 * will also be accessed at each tick.
394 */
395 atomic_long_t load_avg ____cacheline_aligned;
396 #endif
397 #endif
398
399 #ifdef CONFIG_RT_GROUP_SCHED
400 struct sched_rt_entity **rt_se;
401 struct rt_rq **rt_rq;
402
403 struct rt_bandwidth rt_bandwidth;
404 #endif
405
406 struct rcu_head rcu;
407 struct list_head list;
408
409 struct task_group *parent;
410 struct list_head siblings;
411 struct list_head children;
412
413 #ifdef CONFIG_SCHED_AUTOGROUP
414 struct autogroup *autogroup;
415 #endif
416
417 struct cfs_bandwidth cfs_bandwidth;
418
419 #ifdef CONFIG_UCLAMP_TASK_GROUP
420 /* The two decimal precision [%] value requested from user-space */
421 unsigned int uclamp_pct[UCLAMP_CNT];
422 /* Clamp values requested for a task group */
423 struct uclamp_se uclamp_req[UCLAMP_CNT];
424 /* Effective clamp values used for a task group */
425 struct uclamp_se uclamp[UCLAMP_CNT];
426 #endif
427
428 };
429
430 #ifdef CONFIG_FAIR_GROUP_SCHED
431 #define ROOT_TASK_GROUP_LOAD NICE_0_LOAD
432
433 /*
434 * A weight of 0 or 1 can cause arithmetics problems.
435 * A weight of a cfs_rq is the sum of weights of which entities
436 * are queued on this cfs_rq, so a weight of a entity should not be
437 * too large, so as the shares value of a task group.
438 * (The default weight is 1024 - so there's no practical
439 * limitation from this.)
440 */
441 #define MIN_SHARES (1UL << 1)
442 #define MAX_SHARES (1UL << 18)
443 #endif
444
445 typedef int (*tg_visitor)(struct task_group *, void *);
446
447 extern int walk_tg_tree_from(struct task_group *from,
448 tg_visitor down, tg_visitor up, void *data);
449
450 /*
451 * Iterate the full tree, calling @down when first entering a node and @up when
452 * leaving it for the final time.
453 *
454 * Caller must hold rcu_lock or sufficient equivalent.
455 */
456 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
457 {
458 return walk_tg_tree_from(&root_task_group, down, up, data);
459 }
460
461 extern int tg_nop(struct task_group *tg, void *data);
462
463 extern void free_fair_sched_group(struct task_group *tg);
464 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
465 extern void online_fair_sched_group(struct task_group *tg);
466 extern void unregister_fair_sched_group(struct task_group *tg);
467 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
468 struct sched_entity *se, int cpu,
469 struct sched_entity *parent);
470 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
471
472 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
473 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
474 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
475
476 extern void unregister_rt_sched_group(struct task_group *tg);
477 extern void free_rt_sched_group(struct task_group *tg);
478 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
479 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
480 struct sched_rt_entity *rt_se, int cpu,
481 struct sched_rt_entity *parent);
482 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
483 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
484 extern long sched_group_rt_runtime(struct task_group *tg);
485 extern long sched_group_rt_period(struct task_group *tg);
486 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
487
488 extern struct task_group *sched_create_group(struct task_group *parent);
489 extern void sched_online_group(struct task_group *tg,
490 struct task_group *parent);
491 extern void sched_destroy_group(struct task_group *tg);
492 extern void sched_release_group(struct task_group *tg);
493
494 extern void sched_move_task(struct task_struct *tsk);
495
496 #ifdef CONFIG_FAIR_GROUP_SCHED
497 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
498
499 extern int sched_group_set_idle(struct task_group *tg, long idle);
500
501 #ifdef CONFIG_SMP
502 extern void set_task_rq_fair(struct sched_entity *se,
503 struct cfs_rq *prev, struct cfs_rq *next);
504 #else /* !CONFIG_SMP */
505 static inline void set_task_rq_fair(struct sched_entity *se,
506 struct cfs_rq *prev, struct cfs_rq *next) { }
507 #endif /* CONFIG_SMP */
508 #endif /* CONFIG_FAIR_GROUP_SCHED */
509
510 #else /* CONFIG_CGROUP_SCHED */
511
512 struct cfs_bandwidth { };
513
514 #endif /* CONFIG_CGROUP_SCHED */
515
516 /* CFS-related fields in a runqueue */
517 struct cfs_rq {
518 struct load_weight load;
519 unsigned int nr_running;
520 unsigned int h_nr_running; /* SCHED_{NORMAL,BATCH,IDLE} */
521 unsigned int idle_nr_running; /* SCHED_IDLE */
522 unsigned int idle_h_nr_running; /* SCHED_IDLE */
523
524 u64 exec_clock;
525 u64 min_vruntime;
526 #ifdef CONFIG_SCHED_CORE
527 unsigned int forceidle_seq;
528 u64 min_vruntime_fi;
529 #endif
530
531 #ifndef CONFIG_64BIT
532 u64 min_vruntime_copy;
533 #endif
534
535 struct rb_root_cached tasks_timeline;
536
537 /*
538 * 'curr' points to currently running entity on this cfs_rq.
539 * It is set to NULL otherwise (i.e when none are currently running).
540 */
541 struct sched_entity *curr;
542 struct sched_entity *next;
543 struct sched_entity *last;
544 struct sched_entity *skip;
545
546 #ifdef CONFIG_SCHED_DEBUG
547 unsigned int nr_spread_over;
548 #endif
549
550 #ifdef CONFIG_SMP
551 /*
552 * CFS load tracking
553 */
554 struct sched_avg avg;
555 #ifndef CONFIG_64BIT
556 u64 load_last_update_time_copy;
557 #endif
558 struct {
559 raw_spinlock_t lock ____cacheline_aligned;
560 int nr;
561 unsigned long load_avg;
562 unsigned long util_avg;
563 unsigned long runnable_avg;
564 } removed;
565
566 #ifdef CONFIG_FAIR_GROUP_SCHED
567 unsigned long tg_load_avg_contrib;
568 long propagate;
569 long prop_runnable_sum;
570
571 /*
572 * h_load = weight * f(tg)
573 *
574 * Where f(tg) is the recursive weight fraction assigned to
575 * this group.
576 */
577 unsigned long h_load;
578 u64 last_h_load_update;
579 struct sched_entity *h_load_next;
580 #endif /* CONFIG_FAIR_GROUP_SCHED */
581 #endif /* CONFIG_SMP */
582
583 #ifdef CONFIG_FAIR_GROUP_SCHED
584 struct rq *rq; /* CPU runqueue to which this cfs_rq is attached */
585
586 /*
587 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
588 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
589 * (like users, containers etc.)
590 *
591 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
592 * This list is used during load balance.
593 */
594 int on_list;
595 struct list_head leaf_cfs_rq_list;
596 struct task_group *tg; /* group that "owns" this runqueue */
597
598 /* Locally cached copy of our task_group's idle value */
599 int idle;
600
601 #ifdef CONFIG_CFS_BANDWIDTH
602 int runtime_enabled;
603 s64 runtime_remaining;
604
605 u64 throttled_clock;
606 u64 throttled_clock_task;
607 u64 throttled_clock_task_time;
608 int throttled;
609 int throttle_count;
610 struct list_head throttled_list;
611 #endif /* CONFIG_CFS_BANDWIDTH */
612 #endif /* CONFIG_FAIR_GROUP_SCHED */
613 };
614
615 static inline int rt_bandwidth_enabled(void)
616 {
617 return sysctl_sched_rt_runtime >= 0;
618 }
619
620 /* RT IPI pull logic requires IRQ_WORK */
621 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
622 # define HAVE_RT_PUSH_IPI
623 #endif
624
625 /* Real-Time classes' related field in a runqueue: */
626 struct rt_rq {
627 struct rt_prio_array active;
628 unsigned int rt_nr_running;
629 unsigned int rr_nr_running;
630 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
631 struct {
632 int curr; /* highest queued rt task prio */
633 #ifdef CONFIG_SMP
634 int next; /* next highest */
635 #endif
636 } highest_prio;
637 #endif
638 #ifdef CONFIG_SMP
639 unsigned int rt_nr_migratory;
640 unsigned int rt_nr_total;
641 int overloaded;
642 struct plist_head pushable_tasks;
643
644 #endif /* CONFIG_SMP */
645 int rt_queued;
646
647 int rt_throttled;
648 u64 rt_time;
649 u64 rt_runtime;
650 /* Nests inside the rq lock: */
651 raw_spinlock_t rt_runtime_lock;
652
653 #ifdef CONFIG_RT_GROUP_SCHED
654 unsigned int rt_nr_boosted;
655
656 struct rq *rq;
657 struct task_group *tg;
658 #endif
659 };
660
661 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
662 {
663 return rt_rq->rt_queued && rt_rq->rt_nr_running;
664 }
665
666 /* Deadline class' related fields in a runqueue */
667 struct dl_rq {
668 /* runqueue is an rbtree, ordered by deadline */
669 struct rb_root_cached root;
670
671 unsigned int dl_nr_running;
672
673 #ifdef CONFIG_SMP
674 /*
675 * Deadline values of the currently executing and the
676 * earliest ready task on this rq. Caching these facilitates
677 * the decision whether or not a ready but not running task
678 * should migrate somewhere else.
679 */
680 struct {
681 u64 curr;
682 u64 next;
683 } earliest_dl;
684
685 unsigned int dl_nr_migratory;
686 int overloaded;
687
688 /*
689 * Tasks on this rq that can be pushed away. They are kept in
690 * an rb-tree, ordered by tasks' deadlines, with caching
691 * of the leftmost (earliest deadline) element.
692 */
693 struct rb_root_cached pushable_dl_tasks_root;
694 #else
695 struct dl_bw dl_bw;
696 #endif
697 /*
698 * "Active utilization" for this runqueue: increased when a
699 * task wakes up (becomes TASK_RUNNING) and decreased when a
700 * task blocks
701 */
702 u64 running_bw;
703
704 /*
705 * Utilization of the tasks "assigned" to this runqueue (including
706 * the tasks that are in runqueue and the tasks that executed on this
707 * CPU and blocked). Increased when a task moves to this runqueue, and
708 * decreased when the task moves away (migrates, changes scheduling
709 * policy, or terminates).
710 * This is needed to compute the "inactive utilization" for the
711 * runqueue (inactive utilization = this_bw - running_bw).
712 */
713 u64 this_bw;
714 u64 extra_bw;
715
716 /*
717 * Inverse of the fraction of CPU utilization that can be reclaimed
718 * by the GRUB algorithm.
719 */
720 u64 bw_ratio;
721 };
722
723 #ifdef CONFIG_FAIR_GROUP_SCHED
724 /* An entity is a task if it doesn't "own" a runqueue */
725 #define entity_is_task(se) (!se->my_q)
726
727 static inline void se_update_runnable(struct sched_entity *se)
728 {
729 if (!entity_is_task(se))
730 se->runnable_weight = se->my_q->h_nr_running;
731 }
732
733 static inline long se_runnable(struct sched_entity *se)
734 {
735 if (entity_is_task(se))
736 return !!se->on_rq;
737 else
738 return se->runnable_weight;
739 }
740
741 #else
742 #define entity_is_task(se) 1
743
744 static inline void se_update_runnable(struct sched_entity *se) {}
745
746 static inline long se_runnable(struct sched_entity *se)
747 {
748 return !!se->on_rq;
749 }
750 #endif
751
752 #ifdef CONFIG_SMP
753 /*
754 * XXX we want to get rid of these helpers and use the full load resolution.
755 */
756 static inline long se_weight(struct sched_entity *se)
757 {
758 return scale_load_down(se->load.weight);
759 }
760
761
762 static inline bool sched_asym_prefer(int a, int b)
763 {
764 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
765 }
766
767 struct perf_domain {
768 struct em_perf_domain *em_pd;
769 struct perf_domain *next;
770 struct rcu_head rcu;
771 };
772
773 /* Scheduling group status flags */
774 #define SG_OVERLOAD 0x1 /* More than one runnable task on a CPU. */
775 #define SG_OVERUTILIZED 0x2 /* One or more CPUs are over-utilized. */
776
777 /*
778 * We add the notion of a root-domain which will be used to define per-domain
779 * variables. Each exclusive cpuset essentially defines an island domain by
780 * fully partitioning the member CPUs from any other cpuset. Whenever a new
781 * exclusive cpuset is created, we also create and attach a new root-domain
782 * object.
783 *
784 */
785 struct root_domain {
786 atomic_t refcount;
787 atomic_t rto_count;
788 struct rcu_head rcu;
789 cpumask_var_t span;
790 cpumask_var_t online;
791
792 /*
793 * Indicate pullable load on at least one CPU, e.g:
794 * - More than one runnable task
795 * - Running task is misfit
796 */
797 int overload;
798
799 /* Indicate one or more cpus over-utilized (tipping point) */
800 int overutilized;
801
802 /*
803 * The bit corresponding to a CPU gets set here if such CPU has more
804 * than one runnable -deadline task (as it is below for RT tasks).
805 */
806 cpumask_var_t dlo_mask;
807 atomic_t dlo_count;
808 struct dl_bw dl_bw;
809 struct cpudl cpudl;
810
811 /*
812 * Indicate whether a root_domain's dl_bw has been checked or
813 * updated. It's monotonously increasing value.
814 *
815 * Also, some corner cases, like 'wrap around' is dangerous, but given
816 * that u64 is 'big enough'. So that shouldn't be a concern.
817 */
818 u64 visit_gen;
819
820 #ifdef HAVE_RT_PUSH_IPI
821 /*
822 * For IPI pull requests, loop across the rto_mask.
823 */
824 struct irq_work rto_push_work;
825 raw_spinlock_t rto_lock;
826 /* These are only updated and read within rto_lock */
827 int rto_loop;
828 int rto_cpu;
829 /* These atomics are updated outside of a lock */
830 atomic_t rto_loop_next;
831 atomic_t rto_loop_start;
832 #endif
833 /*
834 * The "RT overload" flag: it gets set if a CPU has more than
835 * one runnable RT task.
836 */
837 cpumask_var_t rto_mask;
838 struct cpupri cpupri;
839
840 unsigned long max_cpu_capacity;
841
842 /*
843 * NULL-terminated list of performance domains intersecting with the
844 * CPUs of the rd. Protected by RCU.
845 */
846 struct perf_domain __rcu *pd;
847 };
848
849 extern void init_defrootdomain(void);
850 extern int sched_init_domains(const struct cpumask *cpu_map);
851 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
852 extern void sched_get_rd(struct root_domain *rd);
853 extern void sched_put_rd(struct root_domain *rd);
854
855 #ifdef HAVE_RT_PUSH_IPI
856 extern void rto_push_irq_work_func(struct irq_work *work);
857 #endif
858 #endif /* CONFIG_SMP */
859
860 #ifdef CONFIG_UCLAMP_TASK
861 /*
862 * struct uclamp_bucket - Utilization clamp bucket
863 * @value: utilization clamp value for tasks on this clamp bucket
864 * @tasks: number of RUNNABLE tasks on this clamp bucket
865 *
866 * Keep track of how many tasks are RUNNABLE for a given utilization
867 * clamp value.
868 */
869 struct uclamp_bucket {
870 unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
871 unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
872 };
873
874 /*
875 * struct uclamp_rq - rq's utilization clamp
876 * @value: currently active clamp values for a rq
877 * @bucket: utilization clamp buckets affecting a rq
878 *
879 * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
880 * A clamp value is affecting a rq when there is at least one task RUNNABLE
881 * (or actually running) with that value.
882 *
883 * There are up to UCLAMP_CNT possible different clamp values, currently there
884 * are only two: minimum utilization and maximum utilization.
885 *
886 * All utilization clamping values are MAX aggregated, since:
887 * - for util_min: we want to run the CPU at least at the max of the minimum
888 * utilization required by its currently RUNNABLE tasks.
889 * - for util_max: we want to allow the CPU to run up to the max of the
890 * maximum utilization allowed by its currently RUNNABLE tasks.
891 *
892 * Since on each system we expect only a limited number of different
893 * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
894 * the metrics required to compute all the per-rq utilization clamp values.
895 */
896 struct uclamp_rq {
897 unsigned int value;
898 struct uclamp_bucket bucket[UCLAMP_BUCKETS];
899 };
900
901 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
902 #endif /* CONFIG_UCLAMP_TASK */
903
904 /*
905 * This is the main, per-CPU runqueue data structure.
906 *
907 * Locking rule: those places that want to lock multiple runqueues
908 * (such as the load balancing or the thread migration code), lock
909 * acquire operations must be ordered by ascending &runqueue.
910 */
911 struct rq {
912 /* runqueue lock: */
913 raw_spinlock_t __lock;
914
915 /*
916 * nr_running and cpu_load should be in the same cacheline because
917 * remote CPUs use both these fields when doing load calculation.
918 */
919 unsigned int nr_running;
920 #ifdef CONFIG_NUMA_BALANCING
921 unsigned int nr_numa_running;
922 unsigned int nr_preferred_running;
923 unsigned int numa_migrate_on;
924 #endif
925 #ifdef CONFIG_NO_HZ_COMMON
926 #ifdef CONFIG_SMP
927 unsigned long last_blocked_load_update_tick;
928 unsigned int has_blocked_load;
929 call_single_data_t nohz_csd;
930 #endif /* CONFIG_SMP */
931 unsigned int nohz_tick_stopped;
932 atomic_t nohz_flags;
933 #endif /* CONFIG_NO_HZ_COMMON */
934
935 #ifdef CONFIG_SMP
936 unsigned int ttwu_pending;
937 #endif
938 u64 nr_switches;
939
940 #ifdef CONFIG_UCLAMP_TASK
941 /* Utilization clamp values based on CPU's RUNNABLE tasks */
942 struct uclamp_rq uclamp[UCLAMP_CNT] ____cacheline_aligned;
943 unsigned int uclamp_flags;
944 #define UCLAMP_FLAG_IDLE 0x01
945 #endif
946
947 struct cfs_rq cfs;
948 struct rt_rq rt;
949 struct dl_rq dl;
950
951 #ifdef CONFIG_FAIR_GROUP_SCHED
952 /* list of leaf cfs_rq on this CPU: */
953 struct list_head leaf_cfs_rq_list;
954 struct list_head *tmp_alone_branch;
955 #endif /* CONFIG_FAIR_GROUP_SCHED */
956
957 /*
958 * This is part of a global counter where only the total sum
959 * over all CPUs matters. A task can increase this counter on
960 * one CPU and if it got migrated afterwards it may decrease
961 * it on another CPU. Always updated under the runqueue lock:
962 */
963 unsigned int nr_uninterruptible;
964
965 struct task_struct __rcu *curr;
966 struct task_struct *idle;
967 struct task_struct *stop;
968 unsigned long next_balance;
969 struct mm_struct *prev_mm;
970
971 unsigned int clock_update_flags;
972 u64 clock;
973 /* Ensure that all clocks are in the same cache line */
974 u64 clock_task ____cacheline_aligned;
975 u64 clock_pelt;
976 unsigned long lost_idle_time;
977
978 atomic_t nr_iowait;
979
980 #ifdef CONFIG_SCHED_DEBUG
981 u64 last_seen_need_resched_ns;
982 int ticks_without_resched;
983 #endif
984
985 #ifdef CONFIG_MEMBARRIER
986 int membarrier_state;
987 #endif
988
989 #ifdef CONFIG_SMP
990 struct root_domain *rd;
991 struct sched_domain __rcu *sd;
992
993 unsigned long cpu_capacity;
994 unsigned long cpu_capacity_orig;
995
996 struct callback_head *balance_callback;
997
998 unsigned char nohz_idle_balance;
999 unsigned char idle_balance;
1000
1001 unsigned long misfit_task_load;
1002
1003 /* For active balancing */
1004 int active_balance;
1005 int push_cpu;
1006 struct cpu_stop_work active_balance_work;
1007
1008 /* CPU of this runqueue: */
1009 int cpu;
1010 int online;
1011
1012 struct list_head cfs_tasks;
1013
1014 struct sched_avg avg_rt;
1015 struct sched_avg avg_dl;
1016 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1017 struct sched_avg avg_irq;
1018 #endif
1019 #ifdef CONFIG_SCHED_THERMAL_PRESSURE
1020 struct sched_avg avg_thermal;
1021 #endif
1022 u64 idle_stamp;
1023 u64 avg_idle;
1024
1025 unsigned long wake_stamp;
1026 u64 wake_avg_idle;
1027
1028 /* This is used to determine avg_idle's max value */
1029 u64 max_idle_balance_cost;
1030
1031 #ifdef CONFIG_HOTPLUG_CPU
1032 struct rcuwait hotplug_wait;
1033 #endif
1034 #endif /* CONFIG_SMP */
1035
1036 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1037 u64 prev_irq_time;
1038 #endif
1039 #ifdef CONFIG_PARAVIRT
1040 u64 prev_steal_time;
1041 #endif
1042 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1043 u64 prev_steal_time_rq;
1044 #endif
1045
1046 /* calc_load related fields */
1047 unsigned long calc_load_update;
1048 long calc_load_active;
1049
1050 #ifdef CONFIG_SCHED_HRTICK
1051 #ifdef CONFIG_SMP
1052 call_single_data_t hrtick_csd;
1053 #endif
1054 struct hrtimer hrtick_timer;
1055 ktime_t hrtick_time;
1056 #endif
1057
1058 #ifdef CONFIG_SCHEDSTATS
1059 /* latency stats */
1060 struct sched_info rq_sched_info;
1061 unsigned long long rq_cpu_time;
1062 /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
1063
1064 /* sys_sched_yield() stats */
1065 unsigned int yld_count;
1066
1067 /* schedule() stats */
1068 unsigned int sched_count;
1069 unsigned int sched_goidle;
1070
1071 /* try_to_wake_up() stats */
1072 unsigned int ttwu_count;
1073 unsigned int ttwu_local;
1074 #endif
1075
1076 #ifdef CONFIG_CPU_IDLE
1077 /* Must be inspected within a rcu lock section */
1078 struct cpuidle_state *idle_state;
1079 #endif
1080
1081 #ifdef CONFIG_SMP
1082 unsigned int nr_pinned;
1083 #endif
1084 unsigned int push_busy;
1085 struct cpu_stop_work push_work;
1086
1087 #ifdef CONFIG_SCHED_CORE
1088 /* per rq */
1089 struct rq *core;
1090 struct task_struct *core_pick;
1091 unsigned int core_enabled;
1092 unsigned int core_sched_seq;
1093 struct rb_root core_tree;
1094
1095 /* shared state -- careful with sched_core_cpu_deactivate() */
1096 unsigned int core_task_seq;
1097 unsigned int core_pick_seq;
1098 unsigned long core_cookie;
1099 unsigned int core_forceidle_count;
1100 unsigned int core_forceidle_seq;
1101 unsigned int core_forceidle_occupation;
1102 u64 core_forceidle_start;
1103 #endif
1104 };
1105
1106 #ifdef CONFIG_FAIR_GROUP_SCHED
1107
1108 /* CPU runqueue to which this cfs_rq is attached */
1109 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1110 {
1111 return cfs_rq->rq;
1112 }
1113
1114 #else
1115
1116 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1117 {
1118 return container_of(cfs_rq, struct rq, cfs);
1119 }
1120 #endif
1121
1122 static inline int cpu_of(struct rq *rq)
1123 {
1124 #ifdef CONFIG_SMP
1125 return rq->cpu;
1126 #else
1127 return 0;
1128 #endif
1129 }
1130
1131 #define MDF_PUSH 0x01
1132
1133 static inline bool is_migration_disabled(struct task_struct *p)
1134 {
1135 #ifdef CONFIG_SMP
1136 return p->migration_disabled;
1137 #else
1138 return false;
1139 #endif
1140 }
1141
1142 struct sched_group;
1143 #ifdef CONFIG_SCHED_CORE
1144 static inline struct cpumask *sched_group_span(struct sched_group *sg);
1145
1146 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled);
1147
1148 static inline bool sched_core_enabled(struct rq *rq)
1149 {
1150 return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled;
1151 }
1152
1153 static inline bool sched_core_disabled(void)
1154 {
1155 return !static_branch_unlikely(&__sched_core_enabled);
1156 }
1157
1158 /*
1159 * Be careful with this function; not for general use. The return value isn't
1160 * stable unless you actually hold a relevant rq->__lock.
1161 */
1162 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1163 {
1164 if (sched_core_enabled(rq))
1165 return &rq->core->__lock;
1166
1167 return &rq->__lock;
1168 }
1169
1170 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1171 {
1172 if (rq->core_enabled)
1173 return &rq->core->__lock;
1174
1175 return &rq->__lock;
1176 }
1177
1178 bool cfs_prio_less(struct task_struct *a, struct task_struct *b, bool fi);
1179
1180 /*
1181 * Helpers to check if the CPU's core cookie matches with the task's cookie
1182 * when core scheduling is enabled.
1183 * A special case is that the task's cookie always matches with CPU's core
1184 * cookie if the CPU is in an idle core.
1185 */
1186 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1187 {
1188 /* Ignore cookie match if core scheduler is not enabled on the CPU. */
1189 if (!sched_core_enabled(rq))
1190 return true;
1191
1192 return rq->core->core_cookie == p->core_cookie;
1193 }
1194
1195 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1196 {
1197 bool idle_core = true;
1198 int cpu;
1199
1200 /* Ignore cookie match if core scheduler is not enabled on the CPU. */
1201 if (!sched_core_enabled(rq))
1202 return true;
1203
1204 for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) {
1205 if (!available_idle_cpu(cpu)) {
1206 idle_core = false;
1207 break;
1208 }
1209 }
1210
1211 /*
1212 * A CPU in an idle core is always the best choice for tasks with
1213 * cookies.
1214 */
1215 return idle_core || rq->core->core_cookie == p->core_cookie;
1216 }
1217
1218 static inline bool sched_group_cookie_match(struct rq *rq,
1219 struct task_struct *p,
1220 struct sched_group *group)
1221 {
1222 int cpu;
1223
1224 /* Ignore cookie match if core scheduler is not enabled on the CPU. */
1225 if (!sched_core_enabled(rq))
1226 return true;
1227
1228 for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
1229 if (sched_core_cookie_match(rq, p))
1230 return true;
1231 }
1232 return false;
1233 }
1234
1235 extern void queue_core_balance(struct rq *rq);
1236
1237 static inline bool sched_core_enqueued(struct task_struct *p)
1238 {
1239 return !RB_EMPTY_NODE(&p->core_node);
1240 }
1241
1242 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p);
1243 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags);
1244
1245 extern void sched_core_get(void);
1246 extern void sched_core_put(void);
1247
1248 #else /* !CONFIG_SCHED_CORE */
1249
1250 static inline bool sched_core_enabled(struct rq *rq)
1251 {
1252 return false;
1253 }
1254
1255 static inline bool sched_core_disabled(void)
1256 {
1257 return true;
1258 }
1259
1260 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1261 {
1262 return &rq->__lock;
1263 }
1264
1265 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1266 {
1267 return &rq->__lock;
1268 }
1269
1270 static inline void queue_core_balance(struct rq *rq)
1271 {
1272 }
1273
1274 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1275 {
1276 return true;
1277 }
1278
1279 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1280 {
1281 return true;
1282 }
1283
1284 static inline bool sched_group_cookie_match(struct rq *rq,
1285 struct task_struct *p,
1286 struct sched_group *group)
1287 {
1288 return true;
1289 }
1290 #endif /* CONFIG_SCHED_CORE */
1291
1292 static inline void lockdep_assert_rq_held(struct rq *rq)
1293 {
1294 lockdep_assert_held(__rq_lockp(rq));
1295 }
1296
1297 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass);
1298 extern bool raw_spin_rq_trylock(struct rq *rq);
1299 extern void raw_spin_rq_unlock(struct rq *rq);
1300
1301 static inline void raw_spin_rq_lock(struct rq *rq)
1302 {
1303 raw_spin_rq_lock_nested(rq, 0);
1304 }
1305
1306 static inline void raw_spin_rq_lock_irq(struct rq *rq)
1307 {
1308 local_irq_disable();
1309 raw_spin_rq_lock(rq);
1310 }
1311
1312 static inline void raw_spin_rq_unlock_irq(struct rq *rq)
1313 {
1314 raw_spin_rq_unlock(rq);
1315 local_irq_enable();
1316 }
1317
1318 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq)
1319 {
1320 unsigned long flags;
1321 local_irq_save(flags);
1322 raw_spin_rq_lock(rq);
1323 return flags;
1324 }
1325
1326 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags)
1327 {
1328 raw_spin_rq_unlock(rq);
1329 local_irq_restore(flags);
1330 }
1331
1332 #define raw_spin_rq_lock_irqsave(rq, flags) \
1333 do { \
1334 flags = _raw_spin_rq_lock_irqsave(rq); \
1335 } while (0)
1336
1337 #ifdef CONFIG_SCHED_SMT
1338 extern void __update_idle_core(struct rq *rq);
1339
1340 static inline void update_idle_core(struct rq *rq)
1341 {
1342 if (static_branch_unlikely(&sched_smt_present))
1343 __update_idle_core(rq);
1344 }
1345
1346 #else
1347 static inline void update_idle_core(struct rq *rq) { }
1348 #endif
1349
1350 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1351
1352 #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
1353 #define this_rq() this_cpu_ptr(&runqueues)
1354 #define task_rq(p) cpu_rq(task_cpu(p))
1355 #define cpu_curr(cpu) (cpu_rq(cpu)->curr)
1356 #define raw_rq() raw_cpu_ptr(&runqueues)
1357
1358 #ifdef CONFIG_FAIR_GROUP_SCHED
1359 static inline struct task_struct *task_of(struct sched_entity *se)
1360 {
1361 SCHED_WARN_ON(!entity_is_task(se));
1362 return container_of(se, struct task_struct, se);
1363 }
1364
1365 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1366 {
1367 return p->se.cfs_rq;
1368 }
1369
1370 /* runqueue on which this entity is (to be) queued */
1371 static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se)
1372 {
1373 return se->cfs_rq;
1374 }
1375
1376 /* runqueue "owned" by this group */
1377 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1378 {
1379 return grp->my_q;
1380 }
1381
1382 #else
1383
1384 static inline struct task_struct *task_of(struct sched_entity *se)
1385 {
1386 return container_of(se, struct task_struct, se);
1387 }
1388
1389 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1390 {
1391 return &task_rq(p)->cfs;
1392 }
1393
1394 static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se)
1395 {
1396 struct task_struct *p = task_of(se);
1397 struct rq *rq = task_rq(p);
1398
1399 return &rq->cfs;
1400 }
1401
1402 /* runqueue "owned" by this group */
1403 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1404 {
1405 return NULL;
1406 }
1407 #endif
1408
1409 extern void update_rq_clock(struct rq *rq);
1410
1411 /*
1412 * rq::clock_update_flags bits
1413 *
1414 * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1415 * call to __schedule(). This is an optimisation to avoid
1416 * neighbouring rq clock updates.
1417 *
1418 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1419 * in effect and calls to update_rq_clock() are being ignored.
1420 *
1421 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1422 * made to update_rq_clock() since the last time rq::lock was pinned.
1423 *
1424 * If inside of __schedule(), clock_update_flags will have been
1425 * shifted left (a left shift is a cheap operation for the fast path
1426 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1427 *
1428 * if (rq-clock_update_flags >= RQCF_UPDATED)
1429 *
1430 * to check if %RQCF_UPDATED is set. It'll never be shifted more than
1431 * one position though, because the next rq_unpin_lock() will shift it
1432 * back.
1433 */
1434 #define RQCF_REQ_SKIP 0x01
1435 #define RQCF_ACT_SKIP 0x02
1436 #define RQCF_UPDATED 0x04
1437
1438 static inline void assert_clock_updated(struct rq *rq)
1439 {
1440 /*
1441 * The only reason for not seeing a clock update since the
1442 * last rq_pin_lock() is if we're currently skipping updates.
1443 */
1444 SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
1445 }
1446
1447 static inline u64 rq_clock(struct rq *rq)
1448 {
1449 lockdep_assert_rq_held(rq);
1450 assert_clock_updated(rq);
1451
1452 return rq->clock;
1453 }
1454
1455 static inline u64 rq_clock_task(struct rq *rq)
1456 {
1457 lockdep_assert_rq_held(rq);
1458 assert_clock_updated(rq);
1459
1460 return rq->clock_task;
1461 }
1462
1463 /**
1464 * By default the decay is the default pelt decay period.
1465 * The decay shift can change the decay period in
1466 * multiples of 32.
1467 * Decay shift Decay period(ms)
1468 * 0 32
1469 * 1 64
1470 * 2 128
1471 * 3 256
1472 * 4 512
1473 */
1474 extern int sched_thermal_decay_shift;
1475
1476 static inline u64 rq_clock_thermal(struct rq *rq)
1477 {
1478 return rq_clock_task(rq) >> sched_thermal_decay_shift;
1479 }
1480
1481 static inline void rq_clock_skip_update(struct rq *rq)
1482 {
1483 lockdep_assert_rq_held(rq);
1484 rq->clock_update_flags |= RQCF_REQ_SKIP;
1485 }
1486
1487 /*
1488 * See rt task throttling, which is the only time a skip
1489 * request is canceled.
1490 */
1491 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1492 {
1493 lockdep_assert_rq_held(rq);
1494 rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1495 }
1496
1497 struct rq_flags {
1498 unsigned long flags;
1499 struct pin_cookie cookie;
1500 #ifdef CONFIG_SCHED_DEBUG
1501 /*
1502 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1503 * current pin context is stashed here in case it needs to be
1504 * restored in rq_repin_lock().
1505 */
1506 unsigned int clock_update_flags;
1507 #endif
1508 };
1509
1510 extern struct callback_head balance_push_callback;
1511
1512 /*
1513 * Lockdep annotation that avoids accidental unlocks; it's like a
1514 * sticky/continuous lockdep_assert_held().
1515 *
1516 * This avoids code that has access to 'struct rq *rq' (basically everything in
1517 * the scheduler) from accidentally unlocking the rq if they do not also have a
1518 * copy of the (on-stack) 'struct rq_flags rf'.
1519 *
1520 * Also see Documentation/locking/lockdep-design.rst.
1521 */
1522 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1523 {
1524 rf->cookie = lockdep_pin_lock(__rq_lockp(rq));
1525
1526 #ifdef CONFIG_SCHED_DEBUG
1527 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1528 rf->clock_update_flags = 0;
1529 #ifdef CONFIG_SMP
1530 SCHED_WARN_ON(rq->balance_callback && rq->balance_callback != &balance_push_callback);
1531 #endif
1532 #endif
1533 }
1534
1535 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1536 {
1537 #ifdef CONFIG_SCHED_DEBUG
1538 if (rq->clock_update_flags > RQCF_ACT_SKIP)
1539 rf->clock_update_flags = RQCF_UPDATED;
1540 #endif
1541
1542 lockdep_unpin_lock(__rq_lockp(rq), rf->cookie);
1543 }
1544
1545 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1546 {
1547 lockdep_repin_lock(__rq_lockp(rq), rf->cookie);
1548
1549 #ifdef CONFIG_SCHED_DEBUG
1550 /*
1551 * Restore the value we stashed in @rf for this pin context.
1552 */
1553 rq->clock_update_flags |= rf->clock_update_flags;
1554 #endif
1555 }
1556
1557 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1558 __acquires(rq->lock);
1559
1560 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1561 __acquires(p->pi_lock)
1562 __acquires(rq->lock);
1563
1564 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1565 __releases(rq->lock)
1566 {
1567 rq_unpin_lock(rq, rf);
1568 raw_spin_rq_unlock(rq);
1569 }
1570
1571 static inline void
1572 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1573 __releases(rq->lock)
1574 __releases(p->pi_lock)
1575 {
1576 rq_unpin_lock(rq, rf);
1577 raw_spin_rq_unlock(rq);
1578 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1579 }
1580
1581 static inline void
1582 rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1583 __acquires(rq->lock)
1584 {
1585 raw_spin_rq_lock_irqsave(rq, rf->flags);
1586 rq_pin_lock(rq, rf);
1587 }
1588
1589 static inline void
1590 rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1591 __acquires(rq->lock)
1592 {
1593 raw_spin_rq_lock_irq(rq);
1594 rq_pin_lock(rq, rf);
1595 }
1596
1597 static inline void
1598 rq_lock(struct rq *rq, struct rq_flags *rf)
1599 __acquires(rq->lock)
1600 {
1601 raw_spin_rq_lock(rq);
1602 rq_pin_lock(rq, rf);
1603 }
1604
1605 static inline void
1606 rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1607 __releases(rq->lock)
1608 {
1609 rq_unpin_lock(rq, rf);
1610 raw_spin_rq_unlock_irqrestore(rq, rf->flags);
1611 }
1612
1613 static inline void
1614 rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1615 __releases(rq->lock)
1616 {
1617 rq_unpin_lock(rq, rf);
1618 raw_spin_rq_unlock_irq(rq);
1619 }
1620
1621 static inline void
1622 rq_unlock(struct rq *rq, struct rq_flags *rf)
1623 __releases(rq->lock)
1624 {
1625 rq_unpin_lock(rq, rf);
1626 raw_spin_rq_unlock(rq);
1627 }
1628
1629 static inline struct rq *
1630 this_rq_lock_irq(struct rq_flags *rf)
1631 __acquires(rq->lock)
1632 {
1633 struct rq *rq;
1634
1635 local_irq_disable();
1636 rq = this_rq();
1637 rq_lock(rq, rf);
1638 return rq;
1639 }
1640
1641 #ifdef CONFIG_NUMA
1642 enum numa_topology_type {
1643 NUMA_DIRECT,
1644 NUMA_GLUELESS_MESH,
1645 NUMA_BACKPLANE,
1646 };
1647 extern enum numa_topology_type sched_numa_topology_type;
1648 extern int sched_max_numa_distance;
1649 extern bool find_numa_distance(int distance);
1650 extern void sched_init_numa(int offline_node);
1651 extern void sched_update_numa(int cpu, bool online);
1652 extern void sched_domains_numa_masks_set(unsigned int cpu);
1653 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1654 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1655 #else
1656 static inline void sched_init_numa(int offline_node) { }
1657 static inline void sched_update_numa(int cpu, bool online) { }
1658 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
1659 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1660 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1661 {
1662 return nr_cpu_ids;
1663 }
1664 #endif
1665
1666 #ifdef CONFIG_NUMA_BALANCING
1667 /* The regions in numa_faults array from task_struct */
1668 enum numa_faults_stats {
1669 NUMA_MEM = 0,
1670 NUMA_CPU,
1671 NUMA_MEMBUF,
1672 NUMA_CPUBUF
1673 };
1674 extern void sched_setnuma(struct task_struct *p, int node);
1675 extern int migrate_task_to(struct task_struct *p, int cpu);
1676 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1677 int cpu, int scpu);
1678 extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1679 #else
1680 static inline void
1681 init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1682 {
1683 }
1684 #endif /* CONFIG_NUMA_BALANCING */
1685
1686 #ifdef CONFIG_SMP
1687
1688 static inline void
1689 queue_balance_callback(struct rq *rq,
1690 struct callback_head *head,
1691 void (*func)(struct rq *rq))
1692 {
1693 lockdep_assert_rq_held(rq);
1694
1695 if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
1696 return;
1697
1698 head->func = (void (*)(struct callback_head *))func;
1699 head->next = rq->balance_callback;
1700 rq->balance_callback = head;
1701 }
1702
1703 #define rcu_dereference_check_sched_domain(p) \
1704 rcu_dereference_check((p), \
1705 lockdep_is_held(&sched_domains_mutex))
1706
1707 /*
1708 * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1709 * See destroy_sched_domains: call_rcu for details.
1710 *
1711 * The domain tree of any CPU may only be accessed from within
1712 * preempt-disabled sections.
1713 */
1714 #define for_each_domain(cpu, __sd) \
1715 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1716 __sd; __sd = __sd->parent)
1717
1718 /**
1719 * highest_flag_domain - Return highest sched_domain containing flag.
1720 * @cpu: The CPU whose highest level of sched domain is to
1721 * be returned.
1722 * @flag: The flag to check for the highest sched_domain
1723 * for the given CPU.
1724 *
1725 * Returns the highest sched_domain of a CPU which contains the given flag.
1726 */
1727 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1728 {
1729 struct sched_domain *sd, *hsd = NULL;
1730
1731 for_each_domain(cpu, sd) {
1732 if (!(sd->flags & flag))
1733 break;
1734 hsd = sd;
1735 }
1736
1737 return hsd;
1738 }
1739
1740 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1741 {
1742 struct sched_domain *sd;
1743
1744 for_each_domain(cpu, sd) {
1745 if (sd->flags & flag)
1746 break;
1747 }
1748
1749 return sd;
1750 }
1751
1752 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
1753 DECLARE_PER_CPU(int, sd_llc_size);
1754 DECLARE_PER_CPU(int, sd_llc_id);
1755 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
1756 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
1757 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
1758 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
1759 extern struct static_key_false sched_asym_cpucapacity;
1760
1761 struct sched_group_capacity {
1762 atomic_t ref;
1763 /*
1764 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
1765 * for a single CPU.
1766 */
1767 unsigned long capacity;
1768 unsigned long min_capacity; /* Min per-CPU capacity in group */
1769 unsigned long max_capacity; /* Max per-CPU capacity in group */
1770 unsigned long next_update;
1771 int imbalance; /* XXX unrelated to capacity but shared group state */
1772
1773 #ifdef CONFIG_SCHED_DEBUG
1774 int id;
1775 #endif
1776
1777 unsigned long cpumask[]; /* Balance mask */
1778 };
1779
1780 struct sched_group {
1781 struct sched_group *next; /* Must be a circular list */
1782 atomic_t ref;
1783
1784 unsigned int group_weight;
1785 struct sched_group_capacity *sgc;
1786 int asym_prefer_cpu; /* CPU of highest priority in group */
1787 int flags;
1788
1789 /*
1790 * The CPUs this group covers.
1791 *
1792 * NOTE: this field is variable length. (Allocated dynamically
1793 * by attaching extra space to the end of the structure,
1794 * depending on how many CPUs the kernel has booted up with)
1795 */
1796 unsigned long cpumask[];
1797 };
1798
1799 static inline struct cpumask *sched_group_span(struct sched_group *sg)
1800 {
1801 return to_cpumask(sg->cpumask);
1802 }
1803
1804 /*
1805 * See build_balance_mask().
1806 */
1807 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
1808 {
1809 return to_cpumask(sg->sgc->cpumask);
1810 }
1811
1812 /**
1813 * group_first_cpu - Returns the first CPU in the cpumask of a sched_group.
1814 * @group: The group whose first CPU is to be returned.
1815 */
1816 static inline unsigned int group_first_cpu(struct sched_group *group)
1817 {
1818 return cpumask_first(sched_group_span(group));
1819 }
1820
1821 extern int group_balance_cpu(struct sched_group *sg);
1822
1823 #ifdef CONFIG_SCHED_DEBUG
1824 void update_sched_domain_debugfs(void);
1825 void dirty_sched_domain_sysctl(int cpu);
1826 #else
1827 static inline void update_sched_domain_debugfs(void)
1828 {
1829 }
1830 static inline void dirty_sched_domain_sysctl(int cpu)
1831 {
1832 }
1833 #endif
1834
1835 extern int sched_update_scaling(void);
1836
1837 extern void flush_smp_call_function_from_idle(void);
1838
1839 #else /* !CONFIG_SMP: */
1840 static inline void flush_smp_call_function_from_idle(void) { }
1841 #endif
1842
1843 #include "stats.h"
1844
1845 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS)
1846
1847 extern void __sched_core_account_forceidle(struct rq *rq);
1848
1849 static inline void sched_core_account_forceidle(struct rq *rq)
1850 {
1851 if (schedstat_enabled())
1852 __sched_core_account_forceidle(rq);
1853 }
1854
1855 extern void __sched_core_tick(struct rq *rq);
1856
1857 static inline void sched_core_tick(struct rq *rq)
1858 {
1859 if (sched_core_enabled(rq) && schedstat_enabled())
1860 __sched_core_tick(rq);
1861 }
1862
1863 #else
1864
1865 static inline void sched_core_account_forceidle(struct rq *rq) {}
1866
1867 static inline void sched_core_tick(struct rq *rq) {}
1868
1869 #endif /* CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS */
1870
1871 #ifdef CONFIG_CGROUP_SCHED
1872
1873 /*
1874 * Return the group to which this tasks belongs.
1875 *
1876 * We cannot use task_css() and friends because the cgroup subsystem
1877 * changes that value before the cgroup_subsys::attach() method is called,
1878 * therefore we cannot pin it and might observe the wrong value.
1879 *
1880 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
1881 * core changes this before calling sched_move_task().
1882 *
1883 * Instead we use a 'copy' which is updated from sched_move_task() while
1884 * holding both task_struct::pi_lock and rq::lock.
1885 */
1886 static inline struct task_group *task_group(struct task_struct *p)
1887 {
1888 return p->sched_task_group;
1889 }
1890
1891 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
1892 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
1893 {
1894 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
1895 struct task_group *tg = task_group(p);
1896 #endif
1897
1898 #ifdef CONFIG_FAIR_GROUP_SCHED
1899 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
1900 p->se.cfs_rq = tg->cfs_rq[cpu];
1901 p->se.parent = tg->se[cpu];
1902 #endif
1903
1904 #ifdef CONFIG_RT_GROUP_SCHED
1905 p->rt.rt_rq = tg->rt_rq[cpu];
1906 p->rt.parent = tg->rt_se[cpu];
1907 #endif
1908 }
1909
1910 #else /* CONFIG_CGROUP_SCHED */
1911
1912 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
1913 static inline struct task_group *task_group(struct task_struct *p)
1914 {
1915 return NULL;
1916 }
1917
1918 #endif /* CONFIG_CGROUP_SCHED */
1919
1920 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
1921 {
1922 set_task_rq(p, cpu);
1923 #ifdef CONFIG_SMP
1924 /*
1925 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
1926 * successfully executed on another CPU. We must ensure that updates of
1927 * per-task data have been completed by this moment.
1928 */
1929 smp_wmb();
1930 WRITE_ONCE(task_thread_info(p)->cpu, cpu);
1931 p->wake_cpu = cpu;
1932 #endif
1933 }
1934
1935 /*
1936 * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
1937 */
1938 #ifdef CONFIG_SCHED_DEBUG
1939 # define const_debug __read_mostly
1940 #else
1941 # define const_debug const
1942 #endif
1943
1944 #define SCHED_FEAT(name, enabled) \
1945 __SCHED_FEAT_##name ,
1946
1947 enum {
1948 #include "features.h"
1949 __SCHED_FEAT_NR,
1950 };
1951
1952 #undef SCHED_FEAT
1953
1954 #ifdef CONFIG_SCHED_DEBUG
1955
1956 /*
1957 * To support run-time toggling of sched features, all the translation units
1958 * (but core.c) reference the sysctl_sched_features defined in core.c.
1959 */
1960 extern const_debug unsigned int sysctl_sched_features;
1961
1962 #ifdef CONFIG_JUMP_LABEL
1963 #define SCHED_FEAT(name, enabled) \
1964 static __always_inline bool static_branch_##name(struct static_key *key) \
1965 { \
1966 return static_key_##enabled(key); \
1967 }
1968
1969 #include "features.h"
1970 #undef SCHED_FEAT
1971
1972 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
1973 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
1974
1975 #else /* !CONFIG_JUMP_LABEL */
1976
1977 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1978
1979 #endif /* CONFIG_JUMP_LABEL */
1980
1981 #else /* !SCHED_DEBUG */
1982
1983 /*
1984 * Each translation unit has its own copy of sysctl_sched_features to allow
1985 * constants propagation at compile time and compiler optimization based on
1986 * features default.
1987 */
1988 #define SCHED_FEAT(name, enabled) \
1989 (1UL << __SCHED_FEAT_##name) * enabled |
1990 static const_debug __maybe_unused unsigned int sysctl_sched_features =
1991 #include "features.h"
1992 0;
1993 #undef SCHED_FEAT
1994
1995 #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1996
1997 #endif /* SCHED_DEBUG */
1998
1999 extern struct static_key_false sched_numa_balancing;
2000 extern struct static_key_false sched_schedstats;
2001
2002 static inline u64 global_rt_period(void)
2003 {
2004 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
2005 }
2006
2007 static inline u64 global_rt_runtime(void)
2008 {
2009 if (sysctl_sched_rt_runtime < 0)
2010 return RUNTIME_INF;
2011
2012 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
2013 }
2014
2015 static inline int task_current(struct rq *rq, struct task_struct *p)
2016 {
2017 return rq->curr == p;
2018 }
2019
2020 static inline int task_running(struct rq *rq, struct task_struct *p)
2021 {
2022 #ifdef CONFIG_SMP
2023 return p->on_cpu;
2024 #else
2025 return task_current(rq, p);
2026 #endif
2027 }
2028
2029 static inline int task_on_rq_queued(struct task_struct *p)
2030 {
2031 return p->on_rq == TASK_ON_RQ_QUEUED;
2032 }
2033
2034 static inline int task_on_rq_migrating(struct task_struct *p)
2035 {
2036 return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
2037 }
2038
2039 /* Wake flags. The first three directly map to some SD flag value */
2040 #define WF_EXEC 0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
2041 #define WF_FORK 0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
2042 #define WF_TTWU 0x08 /* Wakeup; maps to SD_BALANCE_WAKE */
2043
2044 #define WF_SYNC 0x10 /* Waker goes to sleep after wakeup */
2045 #define WF_MIGRATED 0x20 /* Internal use, task got migrated */
2046 #define WF_ON_CPU 0x40 /* Wakee is on_cpu */
2047
2048 #ifdef CONFIG_SMP
2049 static_assert(WF_EXEC == SD_BALANCE_EXEC);
2050 static_assert(WF_FORK == SD_BALANCE_FORK);
2051 static_assert(WF_TTWU == SD_BALANCE_WAKE);
2052 #endif
2053
2054 /*
2055 * To aid in avoiding the subversion of "niceness" due to uneven distribution
2056 * of tasks with abnormal "nice" values across CPUs the contribution that
2057 * each task makes to its run queue's load is weighted according to its
2058 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
2059 * scaled version of the new time slice allocation that they receive on time
2060 * slice expiry etc.
2061 */
2062
2063 #define WEIGHT_IDLEPRIO 3
2064 #define WMULT_IDLEPRIO 1431655765
2065
2066 extern const int sched_prio_to_weight[40];
2067 extern const u32 sched_prio_to_wmult[40];
2068
2069 /*
2070 * {de,en}queue flags:
2071 *
2072 * DEQUEUE_SLEEP - task is no longer runnable
2073 * ENQUEUE_WAKEUP - task just became runnable
2074 *
2075 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
2076 * are in a known state which allows modification. Such pairs
2077 * should preserve as much state as possible.
2078 *
2079 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
2080 * in the runqueue.
2081 *
2082 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified)
2083 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
2084 * ENQUEUE_MIGRATED - the task was migrated during wakeup
2085 *
2086 */
2087
2088 #define DEQUEUE_SLEEP 0x01
2089 #define DEQUEUE_SAVE 0x02 /* Matches ENQUEUE_RESTORE */
2090 #define DEQUEUE_MOVE 0x04 /* Matches ENQUEUE_MOVE */
2091 #define DEQUEUE_NOCLOCK 0x08 /* Matches ENQUEUE_NOCLOCK */
2092
2093 #define ENQUEUE_WAKEUP 0x01
2094 #define ENQUEUE_RESTORE 0x02
2095 #define ENQUEUE_MOVE 0x04
2096 #define ENQUEUE_NOCLOCK 0x08
2097
2098 #define ENQUEUE_HEAD 0x10
2099 #define ENQUEUE_REPLENISH 0x20
2100 #ifdef CONFIG_SMP
2101 #define ENQUEUE_MIGRATED 0x40
2102 #else
2103 #define ENQUEUE_MIGRATED 0x00
2104 #endif
2105
2106 #define RETRY_TASK ((void *)-1UL)
2107
2108 struct sched_class {
2109
2110 #ifdef CONFIG_UCLAMP_TASK
2111 int uclamp_enabled;
2112 #endif
2113
2114 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
2115 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
2116 void (*yield_task) (struct rq *rq);
2117 bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
2118
2119 void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags);
2120
2121 struct task_struct *(*pick_next_task)(struct rq *rq);
2122
2123 void (*put_prev_task)(struct rq *rq, struct task_struct *p);
2124 void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
2125
2126 #ifdef CONFIG_SMP
2127 int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2128 int (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
2129
2130 struct task_struct * (*pick_task)(struct rq *rq);
2131
2132 void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
2133
2134 void (*task_woken)(struct rq *this_rq, struct task_struct *task);
2135
2136 void (*set_cpus_allowed)(struct task_struct *p,
2137 const struct cpumask *newmask,
2138 u32 flags);
2139
2140 void (*rq_online)(struct rq *rq);
2141 void (*rq_offline)(struct rq *rq);
2142
2143 struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
2144 #endif
2145
2146 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
2147 void (*task_fork)(struct task_struct *p);
2148 void (*task_dead)(struct task_struct *p);
2149
2150 /*
2151 * The switched_from() call is allowed to drop rq->lock, therefore we
2152 * cannot assume the switched_from/switched_to pair is serialized by
2153 * rq->lock. They are however serialized by p->pi_lock.
2154 */
2155 void (*switched_from)(struct rq *this_rq, struct task_struct *task);
2156 void (*switched_to) (struct rq *this_rq, struct task_struct *task);
2157 void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
2158 int oldprio);
2159
2160 unsigned int (*get_rr_interval)(struct rq *rq,
2161 struct task_struct *task);
2162
2163 void (*update_curr)(struct rq *rq);
2164
2165 #define TASK_SET_GROUP 0
2166 #define TASK_MOVE_GROUP 1
2167
2168 #ifdef CONFIG_FAIR_GROUP_SCHED
2169 void (*task_change_group)(struct task_struct *p, int type);
2170 #endif
2171 };
2172
2173 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
2174 {
2175 WARN_ON_ONCE(rq->curr != prev);
2176 prev->sched_class->put_prev_task(rq, prev);
2177 }
2178
2179 static inline void set_next_task(struct rq *rq, struct task_struct *next)
2180 {
2181 next->sched_class->set_next_task(rq, next, false);
2182 }
2183
2184
2185 /*
2186 * Helper to define a sched_class instance; each one is placed in a separate
2187 * section which is ordered by the linker script:
2188 *
2189 * include/asm-generic/vmlinux.lds.h
2190 *
2191 * Also enforce alignment on the instance, not the type, to guarantee layout.
2192 */
2193 #define DEFINE_SCHED_CLASS(name) \
2194 const struct sched_class name##_sched_class \
2195 __aligned(__alignof__(struct sched_class)) \
2196 __section("__" #name "_sched_class")
2197
2198 /* Defined in include/asm-generic/vmlinux.lds.h */
2199 extern struct sched_class __begin_sched_classes[];
2200 extern struct sched_class __end_sched_classes[];
2201
2202 #define sched_class_highest (__end_sched_classes - 1)
2203 #define sched_class_lowest (__begin_sched_classes - 1)
2204
2205 #define for_class_range(class, _from, _to) \
2206 for (class = (_from); class != (_to); class--)
2207
2208 #define for_each_class(class) \
2209 for_class_range(class, sched_class_highest, sched_class_lowest)
2210
2211 extern const struct sched_class stop_sched_class;
2212 extern const struct sched_class dl_sched_class;
2213 extern const struct sched_class rt_sched_class;
2214 extern const struct sched_class fair_sched_class;
2215 extern const struct sched_class idle_sched_class;
2216
2217 static inline bool sched_stop_runnable(struct rq *rq)
2218 {
2219 return rq->stop && task_on_rq_queued(rq->stop);
2220 }
2221
2222 static inline bool sched_dl_runnable(struct rq *rq)
2223 {
2224 return rq->dl.dl_nr_running > 0;
2225 }
2226
2227 static inline bool sched_rt_runnable(struct rq *rq)
2228 {
2229 return rq->rt.rt_queued > 0;
2230 }
2231
2232 static inline bool sched_fair_runnable(struct rq *rq)
2233 {
2234 return rq->cfs.nr_running > 0;
2235 }
2236
2237 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2238 extern struct task_struct *pick_next_task_idle(struct rq *rq);
2239
2240 #define SCA_CHECK 0x01
2241 #define SCA_MIGRATE_DISABLE 0x02
2242 #define SCA_MIGRATE_ENABLE 0x04
2243 #define SCA_USER 0x08
2244
2245 #ifdef CONFIG_SMP
2246
2247 extern void update_group_capacity(struct sched_domain *sd, int cpu);
2248
2249 extern void trigger_load_balance(struct rq *rq);
2250
2251 extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask, u32 flags);
2252
2253 static inline struct task_struct *get_push_task(struct rq *rq)
2254 {
2255 struct task_struct *p = rq->curr;
2256
2257 lockdep_assert_rq_held(rq);
2258
2259 if (rq->push_busy)
2260 return NULL;
2261
2262 if (p->nr_cpus_allowed == 1)
2263 return NULL;
2264
2265 if (p->migration_disabled)
2266 return NULL;
2267
2268 rq->push_busy = true;
2269 return get_task_struct(p);
2270 }
2271
2272 extern int push_cpu_stop(void *arg);
2273
2274 #endif
2275
2276 #ifdef CONFIG_CPU_IDLE
2277 static inline void idle_set_state(struct rq *rq,
2278 struct cpuidle_state *idle_state)
2279 {
2280 rq->idle_state = idle_state;
2281 }
2282
2283 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2284 {
2285 SCHED_WARN_ON(!rcu_read_lock_held());
2286
2287 return rq->idle_state;
2288 }
2289 #else
2290 static inline void idle_set_state(struct rq *rq,
2291 struct cpuidle_state *idle_state)
2292 {
2293 }
2294
2295 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2296 {
2297 return NULL;
2298 }
2299 #endif
2300
2301 extern void schedule_idle(void);
2302
2303 extern void sysrq_sched_debug_show(void);
2304 extern void sched_init_granularity(void);
2305 extern void update_max_interval(void);
2306
2307 extern void init_sched_dl_class(void);
2308 extern void init_sched_rt_class(void);
2309 extern void init_sched_fair_class(void);
2310
2311 extern void reweight_task(struct task_struct *p, int prio);
2312
2313 extern void resched_curr(struct rq *rq);
2314 extern void resched_cpu(int cpu);
2315
2316 extern struct rt_bandwidth def_rt_bandwidth;
2317 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
2318
2319 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
2320 extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
2321 extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se);
2322
2323 #define BW_SHIFT 20
2324 #define BW_UNIT (1 << BW_SHIFT)
2325 #define RATIO_SHIFT 8
2326 #define MAX_BW_BITS (64 - BW_SHIFT)
2327 #define MAX_BW ((1ULL << MAX_BW_BITS) - 1)
2328 unsigned long to_ratio(u64 period, u64 runtime);
2329
2330 extern void init_entity_runnable_average(struct sched_entity *se);
2331 extern void post_init_entity_util_avg(struct task_struct *p);
2332
2333 #ifdef CONFIG_NO_HZ_FULL
2334 extern bool sched_can_stop_tick(struct rq *rq);
2335 extern int __init sched_tick_offload_init(void);
2336
2337 /*
2338 * Tick may be needed by tasks in the runqueue depending on their policy and
2339 * requirements. If tick is needed, lets send the target an IPI to kick it out of
2340 * nohz mode if necessary.
2341 */
2342 static inline void sched_update_tick_dependency(struct rq *rq)
2343 {
2344 int cpu = cpu_of(rq);
2345
2346 if (!tick_nohz_full_cpu(cpu))
2347 return;
2348
2349 if (sched_can_stop_tick(rq))
2350 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
2351 else
2352 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
2353 }
2354 #else
2355 static inline int sched_tick_offload_init(void) { return 0; }
2356 static inline void sched_update_tick_dependency(struct rq *rq) { }
2357 #endif
2358
2359 static inline void add_nr_running(struct rq *rq, unsigned count)
2360 {
2361 unsigned prev_nr = rq->nr_running;
2362
2363 rq->nr_running = prev_nr + count;
2364 if (trace_sched_update_nr_running_tp_enabled()) {
2365 call_trace_sched_update_nr_running(rq, count);
2366 }
2367
2368 #ifdef CONFIG_SMP
2369 if (prev_nr < 2 && rq->nr_running >= 2) {
2370 if (!READ_ONCE(rq->rd->overload))
2371 WRITE_ONCE(rq->rd->overload, 1);
2372 }
2373 #endif
2374
2375 sched_update_tick_dependency(rq);
2376 }
2377
2378 static inline void sub_nr_running(struct rq *rq, unsigned count)
2379 {
2380 rq->nr_running -= count;
2381 if (trace_sched_update_nr_running_tp_enabled()) {
2382 call_trace_sched_update_nr_running(rq, -count);
2383 }
2384
2385 /* Check if we still need preemption */
2386 sched_update_tick_dependency(rq);
2387 }
2388
2389 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
2390 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
2391
2392 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
2393
2394 extern const_debug unsigned int sysctl_sched_nr_migrate;
2395 extern const_debug unsigned int sysctl_sched_migration_cost;
2396
2397 #ifdef CONFIG_SCHED_DEBUG
2398 extern unsigned int sysctl_sched_latency;
2399 extern unsigned int sysctl_sched_min_granularity;
2400 extern unsigned int sysctl_sched_idle_min_granularity;
2401 extern unsigned int sysctl_sched_wakeup_granularity;
2402 extern int sysctl_resched_latency_warn_ms;
2403 extern int sysctl_resched_latency_warn_once;
2404
2405 extern unsigned int sysctl_sched_tunable_scaling;
2406
2407 extern unsigned int sysctl_numa_balancing_scan_delay;
2408 extern unsigned int sysctl_numa_balancing_scan_period_min;
2409 extern unsigned int sysctl_numa_balancing_scan_period_max;
2410 extern unsigned int sysctl_numa_balancing_scan_size;
2411 #endif
2412
2413 #ifdef CONFIG_SCHED_HRTICK
2414
2415 /*
2416 * Use hrtick when:
2417 * - enabled by features
2418 * - hrtimer is actually high res
2419 */
2420 static inline int hrtick_enabled(struct rq *rq)
2421 {
2422 if (!cpu_active(cpu_of(rq)))
2423 return 0;
2424 return hrtimer_is_hres_active(&rq->hrtick_timer);
2425 }
2426
2427 static inline int hrtick_enabled_fair(struct rq *rq)
2428 {
2429 if (!sched_feat(HRTICK))
2430 return 0;
2431 return hrtick_enabled(rq);
2432 }
2433
2434 static inline int hrtick_enabled_dl(struct rq *rq)
2435 {
2436 if (!sched_feat(HRTICK_DL))
2437 return 0;
2438 return hrtick_enabled(rq);
2439 }
2440
2441 void hrtick_start(struct rq *rq, u64 delay);
2442
2443 #else
2444
2445 static inline int hrtick_enabled_fair(struct rq *rq)
2446 {
2447 return 0;
2448 }
2449
2450 static inline int hrtick_enabled_dl(struct rq *rq)
2451 {
2452 return 0;
2453 }
2454
2455 static inline int hrtick_enabled(struct rq *rq)
2456 {
2457 return 0;
2458 }
2459
2460 #endif /* CONFIG_SCHED_HRTICK */
2461
2462 #ifndef arch_scale_freq_tick
2463 static __always_inline
2464 void arch_scale_freq_tick(void)
2465 {
2466 }
2467 #endif
2468
2469 #ifndef arch_scale_freq_capacity
2470 /**
2471 * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
2472 * @cpu: the CPU in question.
2473 *
2474 * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
2475 *
2476 * f_curr
2477 * ------ * SCHED_CAPACITY_SCALE
2478 * f_max
2479 */
2480 static __always_inline
2481 unsigned long arch_scale_freq_capacity(int cpu)
2482 {
2483 return SCHED_CAPACITY_SCALE;
2484 }
2485 #endif
2486
2487
2488 #ifdef CONFIG_SMP
2489
2490 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2)
2491 {
2492 #ifdef CONFIG_SCHED_CORE
2493 /*
2494 * In order to not have {0,2},{1,3} turn into into an AB-BA,
2495 * order by core-id first and cpu-id second.
2496 *
2497 * Notably:
2498 *
2499 * double_rq_lock(0,3); will take core-0, core-1 lock
2500 * double_rq_lock(1,2); will take core-1, core-0 lock
2501 *
2502 * when only cpu-id is considered.
2503 */
2504 if (rq1->core->cpu < rq2->core->cpu)
2505 return true;
2506 if (rq1->core->cpu > rq2->core->cpu)
2507 return false;
2508
2509 /*
2510 * __sched_core_flip() relies on SMT having cpu-id lock order.
2511 */
2512 #endif
2513 return rq1->cpu < rq2->cpu;
2514 }
2515
2516 extern void double_rq_lock(struct rq *rq1, struct rq *rq2);
2517
2518 #ifdef CONFIG_PREEMPTION
2519
2520 /*
2521 * fair double_lock_balance: Safely acquires both rq->locks in a fair
2522 * way at the expense of forcing extra atomic operations in all
2523 * invocations. This assures that the double_lock is acquired using the
2524 * same underlying policy as the spinlock_t on this architecture, which
2525 * reduces latency compared to the unfair variant below. However, it
2526 * also adds more overhead and therefore may reduce throughput.
2527 */
2528 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2529 __releases(this_rq->lock)
2530 __acquires(busiest->lock)
2531 __acquires(this_rq->lock)
2532 {
2533 raw_spin_rq_unlock(this_rq);
2534 double_rq_lock(this_rq, busiest);
2535
2536 return 1;
2537 }
2538
2539 #else
2540 /*
2541 * Unfair double_lock_balance: Optimizes throughput at the expense of
2542 * latency by eliminating extra atomic operations when the locks are
2543 * already in proper order on entry. This favors lower CPU-ids and will
2544 * grant the double lock to lower CPUs over higher ids under contention,
2545 * regardless of entry order into the function.
2546 */
2547 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2548 __releases(this_rq->lock)
2549 __acquires(busiest->lock)
2550 __acquires(this_rq->lock)
2551 {
2552 if (__rq_lockp(this_rq) == __rq_lockp(busiest))
2553 return 0;
2554
2555 if (likely(raw_spin_rq_trylock(busiest)))
2556 return 0;
2557
2558 if (rq_order_less(this_rq, busiest)) {
2559 raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING);
2560 return 0;
2561 }
2562
2563 raw_spin_rq_unlock(this_rq);
2564 double_rq_lock(this_rq, busiest);
2565
2566 return 1;
2567 }
2568
2569 #endif /* CONFIG_PREEMPTION */
2570
2571 /*
2572 * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
2573 */
2574 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
2575 {
2576 lockdep_assert_irqs_disabled();
2577
2578 return _double_lock_balance(this_rq, busiest);
2579 }
2580
2581 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
2582 __releases(busiest->lock)
2583 {
2584 if (__rq_lockp(this_rq) != __rq_lockp(busiest))
2585 raw_spin_rq_unlock(busiest);
2586 lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_);
2587 }
2588
2589 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
2590 {
2591 if (l1 > l2)
2592 swap(l1, l2);
2593
2594 spin_lock(l1);
2595 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2596 }
2597
2598 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
2599 {
2600 if (l1 > l2)
2601 swap(l1, l2);
2602
2603 spin_lock_irq(l1);
2604 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2605 }
2606
2607 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
2608 {
2609 if (l1 > l2)
2610 swap(l1, l2);
2611
2612 raw_spin_lock(l1);
2613 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2614 }
2615
2616 /*
2617 * double_rq_unlock - safely unlock two runqueues
2618 *
2619 * Note this does not restore interrupts like task_rq_unlock,
2620 * you need to do so manually after calling.
2621 */
2622 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2623 __releases(rq1->lock)
2624 __releases(rq2->lock)
2625 {
2626 if (__rq_lockp(rq1) != __rq_lockp(rq2))
2627 raw_spin_rq_unlock(rq2);
2628 else
2629 __release(rq2->lock);
2630 raw_spin_rq_unlock(rq1);
2631 }
2632
2633 extern void set_rq_online (struct rq *rq);
2634 extern void set_rq_offline(struct rq *rq);
2635 extern bool sched_smp_initialized;
2636
2637 #else /* CONFIG_SMP */
2638
2639 /*
2640 * double_rq_lock - safely lock two runqueues
2641 *
2642 * Note this does not disable interrupts like task_rq_lock,
2643 * you need to do so manually before calling.
2644 */
2645 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2646 __acquires(rq1->lock)
2647 __acquires(rq2->lock)
2648 {
2649 BUG_ON(!irqs_disabled());
2650 BUG_ON(rq1 != rq2);
2651 raw_spin_rq_lock(rq1);
2652 __acquire(rq2->lock); /* Fake it out ;) */
2653 }
2654
2655 /*
2656 * double_rq_unlock - safely unlock two runqueues
2657 *
2658 * Note this does not restore interrupts like task_rq_unlock,
2659 * you need to do so manually after calling.
2660 */
2661 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2662 __releases(rq1->lock)
2663 __releases(rq2->lock)
2664 {
2665 BUG_ON(rq1 != rq2);
2666 raw_spin_rq_unlock(rq1);
2667 __release(rq2->lock);
2668 }
2669
2670 #endif
2671
2672 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
2673 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
2674
2675 #ifdef CONFIG_SCHED_DEBUG
2676 extern bool sched_debug_verbose;
2677
2678 extern void print_cfs_stats(struct seq_file *m, int cpu);
2679 extern void print_rt_stats(struct seq_file *m, int cpu);
2680 extern void print_dl_stats(struct seq_file *m, int cpu);
2681 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
2682 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
2683 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
2684
2685 extern void resched_latency_warn(int cpu, u64 latency);
2686 #ifdef CONFIG_NUMA_BALANCING
2687 extern void
2688 show_numa_stats(struct task_struct *p, struct seq_file *m);
2689 extern void
2690 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
2691 unsigned long tpf, unsigned long gsf, unsigned long gpf);
2692 #endif /* CONFIG_NUMA_BALANCING */
2693 #else
2694 static inline void resched_latency_warn(int cpu, u64 latency) {}
2695 #endif /* CONFIG_SCHED_DEBUG */
2696
2697 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
2698 extern void init_rt_rq(struct rt_rq *rt_rq);
2699 extern void init_dl_rq(struct dl_rq *dl_rq);
2700
2701 extern void cfs_bandwidth_usage_inc(void);
2702 extern void cfs_bandwidth_usage_dec(void);
2703
2704 #ifdef CONFIG_NO_HZ_COMMON
2705 #define NOHZ_BALANCE_KICK_BIT 0
2706 #define NOHZ_STATS_KICK_BIT 1
2707 #define NOHZ_NEWILB_KICK_BIT 2
2708 #define NOHZ_NEXT_KICK_BIT 3
2709
2710 /* Run rebalance_domains() */
2711 #define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT)
2712 /* Update blocked load */
2713 #define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT)
2714 /* Update blocked load when entering idle */
2715 #define NOHZ_NEWILB_KICK BIT(NOHZ_NEWILB_KICK_BIT)
2716 /* Update nohz.next_balance */
2717 #define NOHZ_NEXT_KICK BIT(NOHZ_NEXT_KICK_BIT)
2718
2719 #define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK)
2720
2721 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
2722
2723 extern void nohz_balance_exit_idle(struct rq *rq);
2724 #else
2725 static inline void nohz_balance_exit_idle(struct rq *rq) { }
2726 #endif
2727
2728 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
2729 extern void nohz_run_idle_balance(int cpu);
2730 #else
2731 static inline void nohz_run_idle_balance(int cpu) { }
2732 #endif
2733
2734 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2735 struct irqtime {
2736 u64 total;
2737 u64 tick_delta;
2738 u64 irq_start_time;
2739 struct u64_stats_sync sync;
2740 };
2741
2742 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
2743
2744 /*
2745 * Returns the irqtime minus the softirq time computed by ksoftirqd.
2746 * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime
2747 * and never move forward.
2748 */
2749 static inline u64 irq_time_read(int cpu)
2750 {
2751 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
2752 unsigned int seq;
2753 u64 total;
2754
2755 do {
2756 seq = __u64_stats_fetch_begin(&irqtime->sync);
2757 total = irqtime->total;
2758 } while (__u64_stats_fetch_retry(&irqtime->sync, seq));
2759
2760 return total;
2761 }
2762 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
2763
2764 #ifdef CONFIG_CPU_FREQ
2765 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
2766
2767 /**
2768 * cpufreq_update_util - Take a note about CPU utilization changes.
2769 * @rq: Runqueue to carry out the update for.
2770 * @flags: Update reason flags.
2771 *
2772 * This function is called by the scheduler on the CPU whose utilization is
2773 * being updated.
2774 *
2775 * It can only be called from RCU-sched read-side critical sections.
2776 *
2777 * The way cpufreq is currently arranged requires it to evaluate the CPU
2778 * performance state (frequency/voltage) on a regular basis to prevent it from
2779 * being stuck in a completely inadequate performance level for too long.
2780 * That is not guaranteed to happen if the updates are only triggered from CFS
2781 * and DL, though, because they may not be coming in if only RT tasks are
2782 * active all the time (or there are RT tasks only).
2783 *
2784 * As a workaround for that issue, this function is called periodically by the
2785 * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
2786 * but that really is a band-aid. Going forward it should be replaced with
2787 * solutions targeted more specifically at RT tasks.
2788 */
2789 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
2790 {
2791 struct update_util_data *data;
2792
2793 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
2794 cpu_of(rq)));
2795 if (data)
2796 data->func(data, rq_clock(rq), flags);
2797 }
2798 #else
2799 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
2800 #endif /* CONFIG_CPU_FREQ */
2801
2802 #ifdef arch_scale_freq_capacity
2803 # ifndef arch_scale_freq_invariant
2804 # define arch_scale_freq_invariant() true
2805 # endif
2806 #else
2807 # define arch_scale_freq_invariant() false
2808 #endif
2809
2810 #ifdef CONFIG_SMP
2811 static inline unsigned long capacity_orig_of(int cpu)
2812 {
2813 return cpu_rq(cpu)->cpu_capacity_orig;
2814 }
2815
2816 /**
2817 * enum cpu_util_type - CPU utilization type
2818 * @FREQUENCY_UTIL: Utilization used to select frequency
2819 * @ENERGY_UTIL: Utilization used during energy calculation
2820 *
2821 * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time
2822 * need to be aggregated differently depending on the usage made of them. This
2823 * enum is used within effective_cpu_util() to differentiate the types of
2824 * utilization expected by the callers, and adjust the aggregation accordingly.
2825 */
2826 enum cpu_util_type {
2827 FREQUENCY_UTIL,
2828 ENERGY_UTIL,
2829 };
2830
2831 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
2832 unsigned long max, enum cpu_util_type type,
2833 struct task_struct *p);
2834
2835 static inline unsigned long cpu_bw_dl(struct rq *rq)
2836 {
2837 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
2838 }
2839
2840 static inline unsigned long cpu_util_dl(struct rq *rq)
2841 {
2842 return READ_ONCE(rq->avg_dl.util_avg);
2843 }
2844
2845 /**
2846 * cpu_util_cfs() - Estimates the amount of CPU capacity used by CFS tasks.
2847 * @cpu: the CPU to get the utilization for.
2848 *
2849 * The unit of the return value must be the same as the one of CPU capacity
2850 * so that CPU utilization can be compared with CPU capacity.
2851 *
2852 * CPU utilization is the sum of running time of runnable tasks plus the
2853 * recent utilization of currently non-runnable tasks on that CPU.
2854 * It represents the amount of CPU capacity currently used by CFS tasks in
2855 * the range [0..max CPU capacity] with max CPU capacity being the CPU
2856 * capacity at f_max.
2857 *
2858 * The estimated CPU utilization is defined as the maximum between CPU
2859 * utilization and sum of the estimated utilization of the currently
2860 * runnable tasks on that CPU. It preserves a utilization "snapshot" of
2861 * previously-executed tasks, which helps better deduce how busy a CPU will
2862 * be when a long-sleeping task wakes up. The contribution to CPU utilization
2863 * of such a task would be significantly decayed at this point of time.
2864 *
2865 * CPU utilization can be higher than the current CPU capacity
2866 * (f_curr/f_max * max CPU capacity) or even the max CPU capacity because
2867 * of rounding errors as well as task migrations or wakeups of new tasks.
2868 * CPU utilization has to be capped to fit into the [0..max CPU capacity]
2869 * range. Otherwise a group of CPUs (CPU0 util = 121% + CPU1 util = 80%)
2870 * could be seen as over-utilized even though CPU1 has 20% of spare CPU
2871 * capacity. CPU utilization is allowed to overshoot current CPU capacity
2872 * though since this is useful for predicting the CPU capacity required
2873 * after task migrations (scheduler-driven DVFS).
2874 *
2875 * Return: (Estimated) utilization for the specified CPU.
2876 */
2877 static inline unsigned long cpu_util_cfs(int cpu)
2878 {
2879 struct cfs_rq *cfs_rq;
2880 unsigned long util;
2881
2882 cfs_rq = &cpu_rq(cpu)->cfs;
2883 util = READ_ONCE(cfs_rq->avg.util_avg);
2884
2885 if (sched_feat(UTIL_EST)) {
2886 util = max_t(unsigned long, util,
2887 READ_ONCE(cfs_rq->avg.util_est.enqueued));
2888 }
2889
2890 return min(util, capacity_orig_of(cpu));
2891 }
2892
2893 static inline unsigned long cpu_util_rt(struct rq *rq)
2894 {
2895 return READ_ONCE(rq->avg_rt.util_avg);
2896 }
2897 #endif
2898
2899 #ifdef CONFIG_UCLAMP_TASK
2900 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
2901
2902 /**
2903 * uclamp_rq_util_with - clamp @util with @rq and @p effective uclamp values.
2904 * @rq: The rq to clamp against. Must not be NULL.
2905 * @util: The util value to clamp.
2906 * @p: The task to clamp against. Can be NULL if you want to clamp
2907 * against @rq only.
2908 *
2909 * Clamps the passed @util to the max(@rq, @p) effective uclamp values.
2910 *
2911 * If sched_uclamp_used static key is disabled, then just return the util
2912 * without any clamping since uclamp aggregation at the rq level in the fast
2913 * path is disabled, rendering this operation a NOP.
2914 *
2915 * Use uclamp_eff_value() if you don't care about uclamp values at rq level. It
2916 * will return the correct effective uclamp value of the task even if the
2917 * static key is disabled.
2918 */
2919 static __always_inline
2920 unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
2921 struct task_struct *p)
2922 {
2923 unsigned long min_util = 0;
2924 unsigned long max_util = 0;
2925
2926 if (!static_branch_likely(&sched_uclamp_used))
2927 return util;
2928
2929 if (p) {
2930 min_util = uclamp_eff_value(p, UCLAMP_MIN);
2931 max_util = uclamp_eff_value(p, UCLAMP_MAX);
2932
2933 /*
2934 * Ignore last runnable task's max clamp, as this task will
2935 * reset it. Similarly, no need to read the rq's min clamp.
2936 */
2937 if (rq->uclamp_flags & UCLAMP_FLAG_IDLE)
2938 goto out;
2939 }
2940
2941 min_util = max_t(unsigned long, min_util, READ_ONCE(rq->uclamp[UCLAMP_MIN].value));
2942 max_util = max_t(unsigned long, max_util, READ_ONCE(rq->uclamp[UCLAMP_MAX].value));
2943 out:
2944 /*
2945 * Since CPU's {min,max}_util clamps are MAX aggregated considering
2946 * RUNNABLE tasks with _different_ clamps, we can end up with an
2947 * inversion. Fix it now when the clamps are applied.
2948 */
2949 if (unlikely(min_util >= max_util))
2950 return min_util;
2951
2952 return clamp(util, min_util, max_util);
2953 }
2954
2955 /* Is the rq being capped/throttled by uclamp_max? */
2956 static inline bool uclamp_rq_is_capped(struct rq *rq)
2957 {
2958 unsigned long rq_util;
2959 unsigned long max_util;
2960
2961 if (!static_branch_likely(&sched_uclamp_used))
2962 return false;
2963
2964 rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq);
2965 max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
2966
2967 return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util;
2968 }
2969
2970 /*
2971 * When uclamp is compiled in, the aggregation at rq level is 'turned off'
2972 * by default in the fast path and only gets turned on once userspace performs
2973 * an operation that requires it.
2974 *
2975 * Returns true if userspace opted-in to use uclamp and aggregation at rq level
2976 * hence is active.
2977 */
2978 static inline bool uclamp_is_used(void)
2979 {
2980 return static_branch_likely(&sched_uclamp_used);
2981 }
2982 #else /* CONFIG_UCLAMP_TASK */
2983 static inline
2984 unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
2985 struct task_struct *p)
2986 {
2987 return util;
2988 }
2989
2990 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; }
2991
2992 static inline bool uclamp_is_used(void)
2993 {
2994 return false;
2995 }
2996 #endif /* CONFIG_UCLAMP_TASK */
2997
2998 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
2999 static inline unsigned long cpu_util_irq(struct rq *rq)
3000 {
3001 return rq->avg_irq.util_avg;
3002 }
3003
3004 static inline
3005 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3006 {
3007 util *= (max - irq);
3008 util /= max;
3009
3010 return util;
3011
3012 }
3013 #else
3014 static inline unsigned long cpu_util_irq(struct rq *rq)
3015 {
3016 return 0;
3017 }
3018
3019 static inline
3020 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3021 {
3022 return util;
3023 }
3024 #endif
3025
3026 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
3027
3028 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
3029
3030 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
3031
3032 static inline bool sched_energy_enabled(void)
3033 {
3034 return static_branch_unlikely(&sched_energy_present);
3035 }
3036
3037 #else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
3038
3039 #define perf_domain_span(pd) NULL
3040 static inline bool sched_energy_enabled(void) { return false; }
3041
3042 #endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
3043
3044 #ifdef CONFIG_MEMBARRIER
3045 /*
3046 * The scheduler provides memory barriers required by membarrier between:
3047 * - prior user-space memory accesses and store to rq->membarrier_state,
3048 * - store to rq->membarrier_state and following user-space memory accesses.
3049 * In the same way it provides those guarantees around store to rq->curr.
3050 */
3051 static inline void membarrier_switch_mm(struct rq *rq,
3052 struct mm_struct *prev_mm,
3053 struct mm_struct *next_mm)
3054 {
3055 int membarrier_state;
3056
3057 if (prev_mm == next_mm)
3058 return;
3059
3060 membarrier_state = atomic_read(&next_mm->membarrier_state);
3061 if (READ_ONCE(rq->membarrier_state) == membarrier_state)
3062 return;
3063
3064 WRITE_ONCE(rq->membarrier_state, membarrier_state);
3065 }
3066 #else
3067 static inline void membarrier_switch_mm(struct rq *rq,
3068 struct mm_struct *prev_mm,
3069 struct mm_struct *next_mm)
3070 {
3071 }
3072 #endif
3073
3074 #ifdef CONFIG_SMP
3075 static inline bool is_per_cpu_kthread(struct task_struct *p)
3076 {
3077 if (!(p->flags & PF_KTHREAD))
3078 return false;
3079
3080 if (p->nr_cpus_allowed != 1)
3081 return false;
3082
3083 return true;
3084 }
3085 #endif
3086
3087 extern void swake_up_all_locked(struct swait_queue_head *q);
3088 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
3089
3090 #ifdef CONFIG_PREEMPT_DYNAMIC
3091 extern int preempt_dynamic_mode;
3092 extern int sched_dynamic_mode(const char *str);
3093 extern void sched_dynamic_update(int mode);
3094 #endif
3095
3096 #endif /* _KERNEL_SCHED_SCHED_H */