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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Scheduler internal types and methods:
4 */
5#include <linux/sched.h>
6
7#include <linux/sched/autogroup.h>
8#include <linux/sched/clock.h>
9#include <linux/sched/coredump.h>
10#include <linux/sched/cpufreq.h>
11#include <linux/sched/cputime.h>
12#include <linux/sched/deadline.h>
13#include <linux/sched/debug.h>
14#include <linux/sched/hotplug.h>
15#include <linux/sched/idle.h>
16#include <linux/sched/init.h>
17#include <linux/sched/isolation.h>
18#include <linux/sched/jobctl.h>
19#include <linux/sched/loadavg.h>
20#include <linux/sched/mm.h>
21#include <linux/sched/nohz.h>
22#include <linux/sched/numa_balancing.h>
23#include <linux/sched/prio.h>
24#include <linux/sched/rt.h>
25#include <linux/sched/signal.h>
26#include <linux/sched/smt.h>
27#include <linux/sched/stat.h>
28#include <linux/sched/sysctl.h>
29#include <linux/sched/task.h>
30#include <linux/sched/task_stack.h>
31#include <linux/sched/topology.h>
32#include <linux/sched/user.h>
33#include <linux/sched/wake_q.h>
34#include <linux/sched/xacct.h>
35
36#include <uapi/linux/sched/types.h>
37
38#include <linux/binfmts.h>
39#include <linux/blkdev.h>
40#include <linux/compat.h>
41#include <linux/context_tracking.h>
42#include <linux/cpufreq.h>
43#include <linux/cpuidle.h>
44#include <linux/cpuset.h>
45#include <linux/ctype.h>
46#include <linux/debugfs.h>
47#include <linux/delayacct.h>
48#include <linux/energy_model.h>
49#include <linux/init_task.h>
50#include <linux/kprobes.h>
51#include <linux/kthread.h>
52#include <linux/membarrier.h>
53#include <linux/migrate.h>
54#include <linux/mmu_context.h>
55#include <linux/nmi.h>
56#include <linux/proc_fs.h>
57#include <linux/prefetch.h>
58#include <linux/profile.h>
59#include <linux/psi.h>
60#include <linux/rcupdate_wait.h>
61#include <linux/security.h>
62#include <linux/stop_machine.h>
63#include <linux/suspend.h>
64#include <linux/swait.h>
65#include <linux/syscalls.h>
66#include <linux/task_work.h>
67#include <linux/tsacct_kern.h>
68
69#include <asm/tlb.h>
70
71#ifdef CONFIG_PARAVIRT
72# include <asm/paravirt.h>
73#endif
74
75#include "cpupri.h"
76#include "cpudeadline.h"
77
78#ifdef CONFIG_SCHED_DEBUG
79# define SCHED_WARN_ON(x) WARN_ONCE(x, #x)
80#else
81# define SCHED_WARN_ON(x) ({ (void)(x), 0; })
82#endif
83
84struct rq;
85struct cpuidle_state;
86
87/* task_struct::on_rq states: */
88#define TASK_ON_RQ_QUEUED 1
89#define TASK_ON_RQ_MIGRATING 2
90
91extern __read_mostly int scheduler_running;
92
93extern unsigned long calc_load_update;
94extern atomic_long_t calc_load_tasks;
95
96extern void calc_global_load_tick(struct rq *this_rq);
97extern long calc_load_fold_active(struct rq *this_rq, long adjust);
98
99/*
100 * Helpers for converting nanosecond timing to jiffy resolution
101 */
102#define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
103
104/*
105 * Increase resolution of nice-level calculations for 64-bit architectures.
106 * The extra resolution improves shares distribution and load balancing of
107 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
108 * hierarchies, especially on larger systems. This is not a user-visible change
109 * and does not change the user-interface for setting shares/weights.
110 *
111 * We increase resolution only if we have enough bits to allow this increased
112 * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
113 * are pretty high and the returns do not justify the increased costs.
114 *
115 * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
116 * increase coverage and consistency always enable it on 64-bit platforms.
117 */
118#ifdef CONFIG_64BIT
119# define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
120# define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT)
121# define scale_load_down(w) ((w) >> SCHED_FIXEDPOINT_SHIFT)
122#else
123# define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT)
124# define scale_load(w) (w)
125# define scale_load_down(w) (w)
126#endif
127
128/*
129 * Task weight (visible to users) and its load (invisible to users) have
130 * independent resolution, but they should be well calibrated. We use
131 * scale_load() and scale_load_down(w) to convert between them. The
132 * following must be true:
133 *
134 * scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD
135 *
136 */
137#define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT)
138
139/*
140 * Single value that decides SCHED_DEADLINE internal math precision.
141 * 10 -> just above 1us
142 * 9 -> just above 0.5us
143 */
144#define DL_SCALE 10
145
146/*
147 * Single value that denotes runtime == period, ie unlimited time.
148 */
149#define RUNTIME_INF ((u64)~0ULL)
150
151static inline int idle_policy(int policy)
152{
153 return policy == SCHED_IDLE;
154}
155static inline int fair_policy(int policy)
156{
157 return policy == SCHED_NORMAL || policy == SCHED_BATCH;
158}
159
160static inline int rt_policy(int policy)
161{
162 return policy == SCHED_FIFO || policy == SCHED_RR;
163}
164
165static inline int dl_policy(int policy)
166{
167 return policy == SCHED_DEADLINE;
168}
169static inline bool valid_policy(int policy)
170{
171 return idle_policy(policy) || fair_policy(policy) ||
172 rt_policy(policy) || dl_policy(policy);
173}
174
175static inline int task_has_idle_policy(struct task_struct *p)
176{
177 return idle_policy(p->policy);
178}
179
180static inline int task_has_rt_policy(struct task_struct *p)
181{
182 return rt_policy(p->policy);
183}
184
185static inline int task_has_dl_policy(struct task_struct *p)
186{
187 return dl_policy(p->policy);
188}
189
190#define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
191
192/*
193 * !! For sched_setattr_nocheck() (kernel) only !!
194 *
195 * This is actually gross. :(
196 *
197 * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
198 * tasks, but still be able to sleep. We need this on platforms that cannot
199 * atomically change clock frequency. Remove once fast switching will be
200 * available on such platforms.
201 *
202 * SUGOV stands for SchedUtil GOVernor.
203 */
204#define SCHED_FLAG_SUGOV 0x10000000
205
206static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se)
207{
208#ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
209 return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
210#else
211 return false;
212#endif
213}
214
215/*
216 * Tells if entity @a should preempt entity @b.
217 */
218static inline bool
219dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
220{
221 return dl_entity_is_special(a) ||
222 dl_time_before(a->deadline, b->deadline);
223}
224
225/*
226 * This is the priority-queue data structure of the RT scheduling class:
227 */
228struct rt_prio_array {
229 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
230 struct list_head queue[MAX_RT_PRIO];
231};
232
233struct rt_bandwidth {
234 /* nests inside the rq lock: */
235 raw_spinlock_t rt_runtime_lock;
236 ktime_t rt_period;
237 u64 rt_runtime;
238 struct hrtimer rt_period_timer;
239 unsigned int rt_period_active;
240};
241
242void __dl_clear_params(struct task_struct *p);
243
244/*
245 * To keep the bandwidth of -deadline tasks and groups under control
246 * we need some place where:
247 * - store the maximum -deadline bandwidth of the system (the group);
248 * - cache the fraction of that bandwidth that is currently allocated.
249 *
250 * This is all done in the data structure below. It is similar to the
251 * one used for RT-throttling (rt_bandwidth), with the main difference
252 * that, since here we are only interested in admission control, we
253 * do not decrease any runtime while the group "executes", neither we
254 * need a timer to replenish it.
255 *
256 * With respect to SMP, the bandwidth is given on a per-CPU basis,
257 * meaning that:
258 * - dl_bw (< 100%) is the bandwidth of the system (group) on each CPU;
259 * - dl_total_bw array contains, in the i-eth element, the currently
260 * allocated bandwidth on the i-eth CPU.
261 * Moreover, groups consume bandwidth on each CPU, while tasks only
262 * consume bandwidth on the CPU they're running on.
263 * Finally, dl_total_bw_cpu is used to cache the index of dl_total_bw
264 * that will be shown the next time the proc or cgroup controls will
265 * be red. It on its turn can be changed by writing on its own
266 * control.
267 */
268struct dl_bandwidth {
269 raw_spinlock_t dl_runtime_lock;
270 u64 dl_runtime;
271 u64 dl_period;
272};
273
274static inline int dl_bandwidth_enabled(void)
275{
276 return sysctl_sched_rt_runtime >= 0;
277}
278
279struct dl_bw {
280 raw_spinlock_t lock;
281 u64 bw;
282 u64 total_bw;
283};
284
285static inline void __dl_update(struct dl_bw *dl_b, s64 bw);
286
287static inline
288void __dl_sub(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
289{
290 dl_b->total_bw -= tsk_bw;
291 __dl_update(dl_b, (s32)tsk_bw / cpus);
292}
293
294static inline
295void __dl_add(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
296{
297 dl_b->total_bw += tsk_bw;
298 __dl_update(dl_b, -((s32)tsk_bw / cpus));
299}
300
301static inline
302bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw)
303{
304 return dl_b->bw != -1 &&
305 dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw;
306}
307
308extern void dl_change_utilization(struct task_struct *p, u64 new_bw);
309extern void init_dl_bw(struct dl_bw *dl_b);
310extern int sched_dl_global_validate(void);
311extern void sched_dl_do_global(void);
312extern int sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
313extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
314extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
315extern bool __checkparam_dl(const struct sched_attr *attr);
316extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
317extern int dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
318extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
319extern bool dl_cpu_busy(unsigned int cpu);
320
321#ifdef CONFIG_CGROUP_SCHED
322
323#include <linux/cgroup.h>
324#include <linux/psi.h>
325
326struct cfs_rq;
327struct rt_rq;
328
329extern struct list_head task_groups;
330
331struct cfs_bandwidth {
332#ifdef CONFIG_CFS_BANDWIDTH
333 raw_spinlock_t lock;
334 ktime_t period;
335 u64 quota;
336 u64 runtime;
337 s64 hierarchical_quota;
338
339 u8 idle;
340 u8 period_active;
341 u8 distribute_running;
342 u8 slack_started;
343 struct hrtimer period_timer;
344 struct hrtimer slack_timer;
345 struct list_head throttled_cfs_rq;
346
347 /* Statistics: */
348 int nr_periods;
349 int nr_throttled;
350 u64 throttled_time;
351#endif
352};
353
354/* Task group related information */
355struct task_group {
356 struct cgroup_subsys_state css;
357
358#ifdef CONFIG_FAIR_GROUP_SCHED
359 /* schedulable entities of this group on each CPU */
360 struct sched_entity **se;
361 /* runqueue "owned" by this group on each CPU */
362 struct cfs_rq **cfs_rq;
363 unsigned long shares;
364
365#ifdef CONFIG_SMP
366 /*
367 * load_avg can be heavily contended at clock tick time, so put
368 * it in its own cacheline separated from the fields above which
369 * will also be accessed at each tick.
370 */
371 atomic_long_t load_avg ____cacheline_aligned;
372#endif
373#endif
374
375#ifdef CONFIG_RT_GROUP_SCHED
376 struct sched_rt_entity **rt_se;
377 struct rt_rq **rt_rq;
378
379 struct rt_bandwidth rt_bandwidth;
380#endif
381
382 struct rcu_head rcu;
383 struct list_head list;
384
385 struct task_group *parent;
386 struct list_head siblings;
387 struct list_head children;
388
389#ifdef CONFIG_SCHED_AUTOGROUP
390 struct autogroup *autogroup;
391#endif
392
393 struct cfs_bandwidth cfs_bandwidth;
394
395#ifdef CONFIG_UCLAMP_TASK_GROUP
396 /* The two decimal precision [%] value requested from user-space */
397 unsigned int uclamp_pct[UCLAMP_CNT];
398 /* Clamp values requested for a task group */
399 struct uclamp_se uclamp_req[UCLAMP_CNT];
400 /* Effective clamp values used for a task group */
401 struct uclamp_se uclamp[UCLAMP_CNT];
402#endif
403
404};
405
406#ifdef CONFIG_FAIR_GROUP_SCHED
407#define ROOT_TASK_GROUP_LOAD NICE_0_LOAD
408
409/*
410 * A weight of 0 or 1 can cause arithmetics problems.
411 * A weight of a cfs_rq is the sum of weights of which entities
412 * are queued on this cfs_rq, so a weight of a entity should not be
413 * too large, so as the shares value of a task group.
414 * (The default weight is 1024 - so there's no practical
415 * limitation from this.)
416 */
417#define MIN_SHARES (1UL << 1)
418#define MAX_SHARES (1UL << 18)
419#endif
420
421typedef int (*tg_visitor)(struct task_group *, void *);
422
423extern int walk_tg_tree_from(struct task_group *from,
424 tg_visitor down, tg_visitor up, void *data);
425
426/*
427 * Iterate the full tree, calling @down when first entering a node and @up when
428 * leaving it for the final time.
429 *
430 * Caller must hold rcu_lock or sufficient equivalent.
431 */
432static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
433{
434 return walk_tg_tree_from(&root_task_group, down, up, data);
435}
436
437extern int tg_nop(struct task_group *tg, void *data);
438
439extern void free_fair_sched_group(struct task_group *tg);
440extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
441extern void online_fair_sched_group(struct task_group *tg);
442extern void unregister_fair_sched_group(struct task_group *tg);
443extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
444 struct sched_entity *se, int cpu,
445 struct sched_entity *parent);
446extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
447
448extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
449extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
450extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
451
452extern void free_rt_sched_group(struct task_group *tg);
453extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
454extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
455 struct sched_rt_entity *rt_se, int cpu,
456 struct sched_rt_entity *parent);
457extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
458extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
459extern long sched_group_rt_runtime(struct task_group *tg);
460extern long sched_group_rt_period(struct task_group *tg);
461extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
462
463extern struct task_group *sched_create_group(struct task_group *parent);
464extern void sched_online_group(struct task_group *tg,
465 struct task_group *parent);
466extern void sched_destroy_group(struct task_group *tg);
467extern void sched_offline_group(struct task_group *tg);
468
469extern void sched_move_task(struct task_struct *tsk);
470
471#ifdef CONFIG_FAIR_GROUP_SCHED
472extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
473
474#ifdef CONFIG_SMP
475extern void set_task_rq_fair(struct sched_entity *se,
476 struct cfs_rq *prev, struct cfs_rq *next);
477#else /* !CONFIG_SMP */
478static inline void set_task_rq_fair(struct sched_entity *se,
479 struct cfs_rq *prev, struct cfs_rq *next) { }
480#endif /* CONFIG_SMP */
481#endif /* CONFIG_FAIR_GROUP_SCHED */
482
483#else /* CONFIG_CGROUP_SCHED */
484
485struct cfs_bandwidth { };
486
487#endif /* CONFIG_CGROUP_SCHED */
488
489/* CFS-related fields in a runqueue */
490struct cfs_rq {
491 struct load_weight load;
492 unsigned long runnable_weight;
493 unsigned int nr_running;
494 unsigned int h_nr_running; /* SCHED_{NORMAL,BATCH,IDLE} */
495 unsigned int idle_h_nr_running; /* SCHED_IDLE */
496
497 u64 exec_clock;
498 u64 min_vruntime;
499#ifndef CONFIG_64BIT
500 u64 min_vruntime_copy;
501#endif
502
503 struct rb_root_cached tasks_timeline;
504
505 /*
506 * 'curr' points to currently running entity on this cfs_rq.
507 * It is set to NULL otherwise (i.e when none are currently running).
508 */
509 struct sched_entity *curr;
510 struct sched_entity *next;
511 struct sched_entity *last;
512 struct sched_entity *skip;
513
514#ifdef CONFIG_SCHED_DEBUG
515 unsigned int nr_spread_over;
516#endif
517
518#ifdef CONFIG_SMP
519 /*
520 * CFS load tracking
521 */
522 struct sched_avg avg;
523#ifndef CONFIG_64BIT
524 u64 load_last_update_time_copy;
525#endif
526 struct {
527 raw_spinlock_t lock ____cacheline_aligned;
528 int nr;
529 unsigned long load_avg;
530 unsigned long util_avg;
531 unsigned long runnable_sum;
532 } removed;
533
534#ifdef CONFIG_FAIR_GROUP_SCHED
535 unsigned long tg_load_avg_contrib;
536 long propagate;
537 long prop_runnable_sum;
538
539 /*
540 * h_load = weight * f(tg)
541 *
542 * Where f(tg) is the recursive weight fraction assigned to
543 * this group.
544 */
545 unsigned long h_load;
546 u64 last_h_load_update;
547 struct sched_entity *h_load_next;
548#endif /* CONFIG_FAIR_GROUP_SCHED */
549#endif /* CONFIG_SMP */
550
551#ifdef CONFIG_FAIR_GROUP_SCHED
552 struct rq *rq; /* CPU runqueue to which this cfs_rq is attached */
553
554 /*
555 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
556 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
557 * (like users, containers etc.)
558 *
559 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
560 * This list is used during load balance.
561 */
562 int on_list;
563 struct list_head leaf_cfs_rq_list;
564 struct task_group *tg; /* group that "owns" this runqueue */
565
566#ifdef CONFIG_CFS_BANDWIDTH
567 int runtime_enabled;
568 s64 runtime_remaining;
569
570 u64 throttled_clock;
571 u64 throttled_clock_task;
572 u64 throttled_clock_task_time;
573 int throttled;
574 int throttle_count;
575 struct list_head throttled_list;
576#endif /* CONFIG_CFS_BANDWIDTH */
577#endif /* CONFIG_FAIR_GROUP_SCHED */
578};
579
580static inline int rt_bandwidth_enabled(void)
581{
582 return sysctl_sched_rt_runtime >= 0;
583}
584
585/* RT IPI pull logic requires IRQ_WORK */
586#if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
587# define HAVE_RT_PUSH_IPI
588#endif
589
590/* Real-Time classes' related field in a runqueue: */
591struct rt_rq {
592 struct rt_prio_array active;
593 unsigned int rt_nr_running;
594 unsigned int rr_nr_running;
595#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
596 struct {
597 int curr; /* highest queued rt task prio */
598#ifdef CONFIG_SMP
599 int next; /* next highest */
600#endif
601 } highest_prio;
602#endif
603#ifdef CONFIG_SMP
604 unsigned long rt_nr_migratory;
605 unsigned long rt_nr_total;
606 int overloaded;
607 struct plist_head pushable_tasks;
608
609#endif /* CONFIG_SMP */
610 int rt_queued;
611
612 int rt_throttled;
613 u64 rt_time;
614 u64 rt_runtime;
615 /* Nests inside the rq lock: */
616 raw_spinlock_t rt_runtime_lock;
617
618#ifdef CONFIG_RT_GROUP_SCHED
619 unsigned long rt_nr_boosted;
620
621 struct rq *rq;
622 struct task_group *tg;
623#endif
624};
625
626static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
627{
628 return rt_rq->rt_queued && rt_rq->rt_nr_running;
629}
630
631/* Deadline class' related fields in a runqueue */
632struct dl_rq {
633 /* runqueue is an rbtree, ordered by deadline */
634 struct rb_root_cached root;
635
636 unsigned long dl_nr_running;
637
638#ifdef CONFIG_SMP
639 /*
640 * Deadline values of the currently executing and the
641 * earliest ready task on this rq. Caching these facilitates
642 * the decision whether or not a ready but not running task
643 * should migrate somewhere else.
644 */
645 struct {
646 u64 curr;
647 u64 next;
648 } earliest_dl;
649
650 unsigned long dl_nr_migratory;
651 int overloaded;
652
653 /*
654 * Tasks on this rq that can be pushed away. They are kept in
655 * an rb-tree, ordered by tasks' deadlines, with caching
656 * of the leftmost (earliest deadline) element.
657 */
658 struct rb_root_cached pushable_dl_tasks_root;
659#else
660 struct dl_bw dl_bw;
661#endif
662 /*
663 * "Active utilization" for this runqueue: increased when a
664 * task wakes up (becomes TASK_RUNNING) and decreased when a
665 * task blocks
666 */
667 u64 running_bw;
668
669 /*
670 * Utilization of the tasks "assigned" to this runqueue (including
671 * the tasks that are in runqueue and the tasks that executed on this
672 * CPU and blocked). Increased when a task moves to this runqueue, and
673 * decreased when the task moves away (migrates, changes scheduling
674 * policy, or terminates).
675 * This is needed to compute the "inactive utilization" for the
676 * runqueue (inactive utilization = this_bw - running_bw).
677 */
678 u64 this_bw;
679 u64 extra_bw;
680
681 /*
682 * Inverse of the fraction of CPU utilization that can be reclaimed
683 * by the GRUB algorithm.
684 */
685 u64 bw_ratio;
686};
687
688#ifdef CONFIG_FAIR_GROUP_SCHED
689/* An entity is a task if it doesn't "own" a runqueue */
690#define entity_is_task(se) (!se->my_q)
691#else
692#define entity_is_task(se) 1
693#endif
694
695#ifdef CONFIG_SMP
696/*
697 * XXX we want to get rid of these helpers and use the full load resolution.
698 */
699static inline long se_weight(struct sched_entity *se)
700{
701 return scale_load_down(se->load.weight);
702}
703
704static inline long se_runnable(struct sched_entity *se)
705{
706 return scale_load_down(se->runnable_weight);
707}
708
709static inline bool sched_asym_prefer(int a, int b)
710{
711 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
712}
713
714struct perf_domain {
715 struct em_perf_domain *em_pd;
716 struct perf_domain *next;
717 struct rcu_head rcu;
718};
719
720/* Scheduling group status flags */
721#define SG_OVERLOAD 0x1 /* More than one runnable task on a CPU. */
722#define SG_OVERUTILIZED 0x2 /* One or more CPUs are over-utilized. */
723
724/*
725 * We add the notion of a root-domain which will be used to define per-domain
726 * variables. Each exclusive cpuset essentially defines an island domain by
727 * fully partitioning the member CPUs from any other cpuset. Whenever a new
728 * exclusive cpuset is created, we also create and attach a new root-domain
729 * object.
730 *
731 */
732struct root_domain {
733 atomic_t refcount;
734 atomic_t rto_count;
735 struct rcu_head rcu;
736 cpumask_var_t span;
737 cpumask_var_t online;
738
739 /*
740 * Indicate pullable load on at least one CPU, e.g:
741 * - More than one runnable task
742 * - Running task is misfit
743 */
744 int overload;
745
746 /* Indicate one or more cpus over-utilized (tipping point) */
747 int overutilized;
748
749 /*
750 * The bit corresponding to a CPU gets set here if such CPU has more
751 * than one runnable -deadline task (as it is below for RT tasks).
752 */
753 cpumask_var_t dlo_mask;
754 atomic_t dlo_count;
755 struct dl_bw dl_bw;
756 struct cpudl cpudl;
757
758#ifdef HAVE_RT_PUSH_IPI
759 /*
760 * For IPI pull requests, loop across the rto_mask.
761 */
762 struct irq_work rto_push_work;
763 raw_spinlock_t rto_lock;
764 /* These are only updated and read within rto_lock */
765 int rto_loop;
766 int rto_cpu;
767 /* These atomics are updated outside of a lock */
768 atomic_t rto_loop_next;
769 atomic_t rto_loop_start;
770#endif
771 /*
772 * The "RT overload" flag: it gets set if a CPU has more than
773 * one runnable RT task.
774 */
775 cpumask_var_t rto_mask;
776 struct cpupri cpupri;
777
778 unsigned long max_cpu_capacity;
779
780 /*
781 * NULL-terminated list of performance domains intersecting with the
782 * CPUs of the rd. Protected by RCU.
783 */
784 struct perf_domain __rcu *pd;
785};
786
787extern void init_defrootdomain(void);
788extern int sched_init_domains(const struct cpumask *cpu_map);
789extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
790extern void sched_get_rd(struct root_domain *rd);
791extern void sched_put_rd(struct root_domain *rd);
792
793#ifdef HAVE_RT_PUSH_IPI
794extern void rto_push_irq_work_func(struct irq_work *work);
795#endif
796#endif /* CONFIG_SMP */
797
798#ifdef CONFIG_UCLAMP_TASK
799/*
800 * struct uclamp_bucket - Utilization clamp bucket
801 * @value: utilization clamp value for tasks on this clamp bucket
802 * @tasks: number of RUNNABLE tasks on this clamp bucket
803 *
804 * Keep track of how many tasks are RUNNABLE for a given utilization
805 * clamp value.
806 */
807struct uclamp_bucket {
808 unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
809 unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
810};
811
812/*
813 * struct uclamp_rq - rq's utilization clamp
814 * @value: currently active clamp values for a rq
815 * @bucket: utilization clamp buckets affecting a rq
816 *
817 * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
818 * A clamp value is affecting a rq when there is at least one task RUNNABLE
819 * (or actually running) with that value.
820 *
821 * There are up to UCLAMP_CNT possible different clamp values, currently there
822 * are only two: minimum utilization and maximum utilization.
823 *
824 * All utilization clamping values are MAX aggregated, since:
825 * - for util_min: we want to run the CPU at least at the max of the minimum
826 * utilization required by its currently RUNNABLE tasks.
827 * - for util_max: we want to allow the CPU to run up to the max of the
828 * maximum utilization allowed by its currently RUNNABLE tasks.
829 *
830 * Since on each system we expect only a limited number of different
831 * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
832 * the metrics required to compute all the per-rq utilization clamp values.
833 */
834struct uclamp_rq {
835 unsigned int value;
836 struct uclamp_bucket bucket[UCLAMP_BUCKETS];
837};
838#endif /* CONFIG_UCLAMP_TASK */
839
840/*
841 * This is the main, per-CPU runqueue data structure.
842 *
843 * Locking rule: those places that want to lock multiple runqueues
844 * (such as the load balancing or the thread migration code), lock
845 * acquire operations must be ordered by ascending &runqueue.
846 */
847struct rq {
848 /* runqueue lock: */
849 raw_spinlock_t lock;
850
851 /*
852 * nr_running and cpu_load should be in the same cacheline because
853 * remote CPUs use both these fields when doing load calculation.
854 */
855 unsigned int nr_running;
856#ifdef CONFIG_NUMA_BALANCING
857 unsigned int nr_numa_running;
858 unsigned int nr_preferred_running;
859 unsigned int numa_migrate_on;
860#endif
861#ifdef CONFIG_NO_HZ_COMMON
862#ifdef CONFIG_SMP
863 unsigned long last_load_update_tick;
864 unsigned long last_blocked_load_update_tick;
865 unsigned int has_blocked_load;
866#endif /* CONFIG_SMP */
867 unsigned int nohz_tick_stopped;
868 atomic_t nohz_flags;
869#endif /* CONFIG_NO_HZ_COMMON */
870
871 unsigned long nr_load_updates;
872 u64 nr_switches;
873
874#ifdef CONFIG_UCLAMP_TASK
875 /* Utilization clamp values based on CPU's RUNNABLE tasks */
876 struct uclamp_rq uclamp[UCLAMP_CNT] ____cacheline_aligned;
877 unsigned int uclamp_flags;
878#define UCLAMP_FLAG_IDLE 0x01
879#endif
880
881 struct cfs_rq cfs;
882 struct rt_rq rt;
883 struct dl_rq dl;
884
885#ifdef CONFIG_FAIR_GROUP_SCHED
886 /* list of leaf cfs_rq on this CPU: */
887 struct list_head leaf_cfs_rq_list;
888 struct list_head *tmp_alone_branch;
889#endif /* CONFIG_FAIR_GROUP_SCHED */
890
891 /*
892 * This is part of a global counter where only the total sum
893 * over all CPUs matters. A task can increase this counter on
894 * one CPU and if it got migrated afterwards it may decrease
895 * it on another CPU. Always updated under the runqueue lock:
896 */
897 unsigned long nr_uninterruptible;
898
899 struct task_struct *curr;
900 struct task_struct *idle;
901 struct task_struct *stop;
902 unsigned long next_balance;
903 struct mm_struct *prev_mm;
904
905 unsigned int clock_update_flags;
906 u64 clock;
907 /* Ensure that all clocks are in the same cache line */
908 u64 clock_task ____cacheline_aligned;
909 u64 clock_pelt;
910 unsigned long lost_idle_time;
911
912 atomic_t nr_iowait;
913
914#ifdef CONFIG_MEMBARRIER
915 int membarrier_state;
916#endif
917
918#ifdef CONFIG_SMP
919 struct root_domain *rd;
920 struct sched_domain __rcu *sd;
921
922 unsigned long cpu_capacity;
923 unsigned long cpu_capacity_orig;
924
925 struct callback_head *balance_callback;
926
927 unsigned char idle_balance;
928
929 unsigned long misfit_task_load;
930
931 /* For active balancing */
932 int active_balance;
933 int push_cpu;
934 struct cpu_stop_work active_balance_work;
935
936 /* CPU of this runqueue: */
937 int cpu;
938 int online;
939
940 struct list_head cfs_tasks;
941
942 struct sched_avg avg_rt;
943 struct sched_avg avg_dl;
944#ifdef CONFIG_HAVE_SCHED_AVG_IRQ
945 struct sched_avg avg_irq;
946#endif
947 u64 idle_stamp;
948 u64 avg_idle;
949
950 /* This is used to determine avg_idle's max value */
951 u64 max_idle_balance_cost;
952#endif
953
954#ifdef CONFIG_IRQ_TIME_ACCOUNTING
955 u64 prev_irq_time;
956#endif
957#ifdef CONFIG_PARAVIRT
958 u64 prev_steal_time;
959#endif
960#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
961 u64 prev_steal_time_rq;
962#endif
963
964 /* calc_load related fields */
965 unsigned long calc_load_update;
966 long calc_load_active;
967
968#ifdef CONFIG_SCHED_HRTICK
969#ifdef CONFIG_SMP
970 int hrtick_csd_pending;
971 call_single_data_t hrtick_csd;
972#endif
973 struct hrtimer hrtick_timer;
974#endif
975
976#ifdef CONFIG_SCHEDSTATS
977 /* latency stats */
978 struct sched_info rq_sched_info;
979 unsigned long long rq_cpu_time;
980 /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
981
982 /* sys_sched_yield() stats */
983 unsigned int yld_count;
984
985 /* schedule() stats */
986 unsigned int sched_count;
987 unsigned int sched_goidle;
988
989 /* try_to_wake_up() stats */
990 unsigned int ttwu_count;
991 unsigned int ttwu_local;
992#endif
993
994#ifdef CONFIG_SMP
995 struct llist_head wake_list;
996#endif
997
998#ifdef CONFIG_CPU_IDLE
999 /* Must be inspected within a rcu lock section */
1000 struct cpuidle_state *idle_state;
1001#endif
1002};
1003
1004#ifdef CONFIG_FAIR_GROUP_SCHED
1005
1006/* CPU runqueue to which this cfs_rq is attached */
1007static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1008{
1009 return cfs_rq->rq;
1010}
1011
1012#else
1013
1014static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1015{
1016 return container_of(cfs_rq, struct rq, cfs);
1017}
1018#endif
1019
1020static inline int cpu_of(struct rq *rq)
1021{
1022#ifdef CONFIG_SMP
1023 return rq->cpu;
1024#else
1025 return 0;
1026#endif
1027}
1028
1029
1030#ifdef CONFIG_SCHED_SMT
1031extern void __update_idle_core(struct rq *rq);
1032
1033static inline void update_idle_core(struct rq *rq)
1034{
1035 if (static_branch_unlikely(&sched_smt_present))
1036 __update_idle_core(rq);
1037}
1038
1039#else
1040static inline void update_idle_core(struct rq *rq) { }
1041#endif
1042
1043DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1044
1045#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
1046#define this_rq() this_cpu_ptr(&runqueues)
1047#define task_rq(p) cpu_rq(task_cpu(p))
1048#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
1049#define raw_rq() raw_cpu_ptr(&runqueues)
1050
1051extern void update_rq_clock(struct rq *rq);
1052
1053static inline u64 __rq_clock_broken(struct rq *rq)
1054{
1055 return READ_ONCE(rq->clock);
1056}
1057
1058/*
1059 * rq::clock_update_flags bits
1060 *
1061 * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1062 * call to __schedule(). This is an optimisation to avoid
1063 * neighbouring rq clock updates.
1064 *
1065 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1066 * in effect and calls to update_rq_clock() are being ignored.
1067 *
1068 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1069 * made to update_rq_clock() since the last time rq::lock was pinned.
1070 *
1071 * If inside of __schedule(), clock_update_flags will have been
1072 * shifted left (a left shift is a cheap operation for the fast path
1073 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1074 *
1075 * if (rq-clock_update_flags >= RQCF_UPDATED)
1076 *
1077 * to check if %RQCF_UPADTED is set. It'll never be shifted more than
1078 * one position though, because the next rq_unpin_lock() will shift it
1079 * back.
1080 */
1081#define RQCF_REQ_SKIP 0x01
1082#define RQCF_ACT_SKIP 0x02
1083#define RQCF_UPDATED 0x04
1084
1085static inline void assert_clock_updated(struct rq *rq)
1086{
1087 /*
1088 * The only reason for not seeing a clock update since the
1089 * last rq_pin_lock() is if we're currently skipping updates.
1090 */
1091 SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
1092}
1093
1094static inline u64 rq_clock(struct rq *rq)
1095{
1096 lockdep_assert_held(&rq->lock);
1097 assert_clock_updated(rq);
1098
1099 return rq->clock;
1100}
1101
1102static inline u64 rq_clock_task(struct rq *rq)
1103{
1104 lockdep_assert_held(&rq->lock);
1105 assert_clock_updated(rq);
1106
1107 return rq->clock_task;
1108}
1109
1110static inline void rq_clock_skip_update(struct rq *rq)
1111{
1112 lockdep_assert_held(&rq->lock);
1113 rq->clock_update_flags |= RQCF_REQ_SKIP;
1114}
1115
1116/*
1117 * See rt task throttling, which is the only time a skip
1118 * request is cancelled.
1119 */
1120static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1121{
1122 lockdep_assert_held(&rq->lock);
1123 rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1124}
1125
1126struct rq_flags {
1127 unsigned long flags;
1128 struct pin_cookie cookie;
1129#ifdef CONFIG_SCHED_DEBUG
1130 /*
1131 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1132 * current pin context is stashed here in case it needs to be
1133 * restored in rq_repin_lock().
1134 */
1135 unsigned int clock_update_flags;
1136#endif
1137};
1138
1139static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1140{
1141 rf->cookie = lockdep_pin_lock(&rq->lock);
1142
1143#ifdef CONFIG_SCHED_DEBUG
1144 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1145 rf->clock_update_flags = 0;
1146#endif
1147}
1148
1149static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1150{
1151#ifdef CONFIG_SCHED_DEBUG
1152 if (rq->clock_update_flags > RQCF_ACT_SKIP)
1153 rf->clock_update_flags = RQCF_UPDATED;
1154#endif
1155
1156 lockdep_unpin_lock(&rq->lock, rf->cookie);
1157}
1158
1159static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1160{
1161 lockdep_repin_lock(&rq->lock, rf->cookie);
1162
1163#ifdef CONFIG_SCHED_DEBUG
1164 /*
1165 * Restore the value we stashed in @rf for this pin context.
1166 */
1167 rq->clock_update_flags |= rf->clock_update_flags;
1168#endif
1169}
1170
1171struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1172 __acquires(rq->lock);
1173
1174struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1175 __acquires(p->pi_lock)
1176 __acquires(rq->lock);
1177
1178static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1179 __releases(rq->lock)
1180{
1181 rq_unpin_lock(rq, rf);
1182 raw_spin_unlock(&rq->lock);
1183}
1184
1185static inline void
1186task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1187 __releases(rq->lock)
1188 __releases(p->pi_lock)
1189{
1190 rq_unpin_lock(rq, rf);
1191 raw_spin_unlock(&rq->lock);
1192 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1193}
1194
1195static inline void
1196rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1197 __acquires(rq->lock)
1198{
1199 raw_spin_lock_irqsave(&rq->lock, rf->flags);
1200 rq_pin_lock(rq, rf);
1201}
1202
1203static inline void
1204rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1205 __acquires(rq->lock)
1206{
1207 raw_spin_lock_irq(&rq->lock);
1208 rq_pin_lock(rq, rf);
1209}
1210
1211static inline void
1212rq_lock(struct rq *rq, struct rq_flags *rf)
1213 __acquires(rq->lock)
1214{
1215 raw_spin_lock(&rq->lock);
1216 rq_pin_lock(rq, rf);
1217}
1218
1219static inline void
1220rq_relock(struct rq *rq, struct rq_flags *rf)
1221 __acquires(rq->lock)
1222{
1223 raw_spin_lock(&rq->lock);
1224 rq_repin_lock(rq, rf);
1225}
1226
1227static inline void
1228rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1229 __releases(rq->lock)
1230{
1231 rq_unpin_lock(rq, rf);
1232 raw_spin_unlock_irqrestore(&rq->lock, rf->flags);
1233}
1234
1235static inline void
1236rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1237 __releases(rq->lock)
1238{
1239 rq_unpin_lock(rq, rf);
1240 raw_spin_unlock_irq(&rq->lock);
1241}
1242
1243static inline void
1244rq_unlock(struct rq *rq, struct rq_flags *rf)
1245 __releases(rq->lock)
1246{
1247 rq_unpin_lock(rq, rf);
1248 raw_spin_unlock(&rq->lock);
1249}
1250
1251static inline struct rq *
1252this_rq_lock_irq(struct rq_flags *rf)
1253 __acquires(rq->lock)
1254{
1255 struct rq *rq;
1256
1257 local_irq_disable();
1258 rq = this_rq();
1259 rq_lock(rq, rf);
1260 return rq;
1261}
1262
1263#ifdef CONFIG_NUMA
1264enum numa_topology_type {
1265 NUMA_DIRECT,
1266 NUMA_GLUELESS_MESH,
1267 NUMA_BACKPLANE,
1268};
1269extern enum numa_topology_type sched_numa_topology_type;
1270extern int sched_max_numa_distance;
1271extern bool find_numa_distance(int distance);
1272extern void sched_init_numa(void);
1273extern void sched_domains_numa_masks_set(unsigned int cpu);
1274extern void sched_domains_numa_masks_clear(unsigned int cpu);
1275extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1276#else
1277static inline void sched_init_numa(void) { }
1278static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
1279static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1280static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1281{
1282 return nr_cpu_ids;
1283}
1284#endif
1285
1286#ifdef CONFIG_NUMA_BALANCING
1287/* The regions in numa_faults array from task_struct */
1288enum numa_faults_stats {
1289 NUMA_MEM = 0,
1290 NUMA_CPU,
1291 NUMA_MEMBUF,
1292 NUMA_CPUBUF
1293};
1294extern void sched_setnuma(struct task_struct *p, int node);
1295extern int migrate_task_to(struct task_struct *p, int cpu);
1296extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1297 int cpu, int scpu);
1298extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1299#else
1300static inline void
1301init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1302{
1303}
1304#endif /* CONFIG_NUMA_BALANCING */
1305
1306#ifdef CONFIG_SMP
1307
1308static inline void
1309queue_balance_callback(struct rq *rq,
1310 struct callback_head *head,
1311 void (*func)(struct rq *rq))
1312{
1313 lockdep_assert_held(&rq->lock);
1314
1315 if (unlikely(head->next))
1316 return;
1317
1318 head->func = (void (*)(struct callback_head *))func;
1319 head->next = rq->balance_callback;
1320 rq->balance_callback = head;
1321}
1322
1323extern void sched_ttwu_pending(void);
1324
1325#define rcu_dereference_check_sched_domain(p) \
1326 rcu_dereference_check((p), \
1327 lockdep_is_held(&sched_domains_mutex))
1328
1329/*
1330 * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1331 * See destroy_sched_domains: call_rcu for details.
1332 *
1333 * The domain tree of any CPU may only be accessed from within
1334 * preempt-disabled sections.
1335 */
1336#define for_each_domain(cpu, __sd) \
1337 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1338 __sd; __sd = __sd->parent)
1339
1340#define for_each_lower_domain(sd) for (; sd; sd = sd->child)
1341
1342/**
1343 * highest_flag_domain - Return highest sched_domain containing flag.
1344 * @cpu: The CPU whose highest level of sched domain is to
1345 * be returned.
1346 * @flag: The flag to check for the highest sched_domain
1347 * for the given CPU.
1348 *
1349 * Returns the highest sched_domain of a CPU which contains the given flag.
1350 */
1351static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1352{
1353 struct sched_domain *sd, *hsd = NULL;
1354
1355 for_each_domain(cpu, sd) {
1356 if (!(sd->flags & flag))
1357 break;
1358 hsd = sd;
1359 }
1360
1361 return hsd;
1362}
1363
1364static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1365{
1366 struct sched_domain *sd;
1367
1368 for_each_domain(cpu, sd) {
1369 if (sd->flags & flag)
1370 break;
1371 }
1372
1373 return sd;
1374}
1375
1376DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
1377DECLARE_PER_CPU(int, sd_llc_size);
1378DECLARE_PER_CPU(int, sd_llc_id);
1379DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
1380DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
1381DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
1382DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
1383extern struct static_key_false sched_asym_cpucapacity;
1384
1385struct sched_group_capacity {
1386 atomic_t ref;
1387 /*
1388 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
1389 * for a single CPU.
1390 */
1391 unsigned long capacity;
1392 unsigned long min_capacity; /* Min per-CPU capacity in group */
1393 unsigned long max_capacity; /* Max per-CPU capacity in group */
1394 unsigned long next_update;
1395 int imbalance; /* XXX unrelated to capacity but shared group state */
1396
1397#ifdef CONFIG_SCHED_DEBUG
1398 int id;
1399#endif
1400
1401 unsigned long cpumask[0]; /* Balance mask */
1402};
1403
1404struct sched_group {
1405 struct sched_group *next; /* Must be a circular list */
1406 atomic_t ref;
1407
1408 unsigned int group_weight;
1409 struct sched_group_capacity *sgc;
1410 int asym_prefer_cpu; /* CPU of highest priority in group */
1411
1412 /*
1413 * The CPUs this group covers.
1414 *
1415 * NOTE: this field is variable length. (Allocated dynamically
1416 * by attaching extra space to the end of the structure,
1417 * depending on how many CPUs the kernel has booted up with)
1418 */
1419 unsigned long cpumask[0];
1420};
1421
1422static inline struct cpumask *sched_group_span(struct sched_group *sg)
1423{
1424 return to_cpumask(sg->cpumask);
1425}
1426
1427/*
1428 * See build_balance_mask().
1429 */
1430static inline struct cpumask *group_balance_mask(struct sched_group *sg)
1431{
1432 return to_cpumask(sg->sgc->cpumask);
1433}
1434
1435/**
1436 * group_first_cpu - Returns the first CPU in the cpumask of a sched_group.
1437 * @group: The group whose first CPU is to be returned.
1438 */
1439static inline unsigned int group_first_cpu(struct sched_group *group)
1440{
1441 return cpumask_first(sched_group_span(group));
1442}
1443
1444extern int group_balance_cpu(struct sched_group *sg);
1445
1446#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
1447void register_sched_domain_sysctl(void);
1448void dirty_sched_domain_sysctl(int cpu);
1449void unregister_sched_domain_sysctl(void);
1450#else
1451static inline void register_sched_domain_sysctl(void)
1452{
1453}
1454static inline void dirty_sched_domain_sysctl(int cpu)
1455{
1456}
1457static inline void unregister_sched_domain_sysctl(void)
1458{
1459}
1460#endif
1461
1462extern int newidle_balance(struct rq *this_rq, struct rq_flags *rf);
1463
1464#else
1465
1466static inline void sched_ttwu_pending(void) { }
1467
1468static inline int newidle_balance(struct rq *this_rq, struct rq_flags *rf) { return 0; }
1469
1470#endif /* CONFIG_SMP */
1471
1472#include "stats.h"
1473#include "autogroup.h"
1474
1475#ifdef CONFIG_CGROUP_SCHED
1476
1477/*
1478 * Return the group to which this tasks belongs.
1479 *
1480 * We cannot use task_css() and friends because the cgroup subsystem
1481 * changes that value before the cgroup_subsys::attach() method is called,
1482 * therefore we cannot pin it and might observe the wrong value.
1483 *
1484 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
1485 * core changes this before calling sched_move_task().
1486 *
1487 * Instead we use a 'copy' which is updated from sched_move_task() while
1488 * holding both task_struct::pi_lock and rq::lock.
1489 */
1490static inline struct task_group *task_group(struct task_struct *p)
1491{
1492 return p->sched_task_group;
1493}
1494
1495/* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
1496static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
1497{
1498#if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
1499 struct task_group *tg = task_group(p);
1500#endif
1501
1502#ifdef CONFIG_FAIR_GROUP_SCHED
1503 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
1504 p->se.cfs_rq = tg->cfs_rq[cpu];
1505 p->se.parent = tg->se[cpu];
1506#endif
1507
1508#ifdef CONFIG_RT_GROUP_SCHED
1509 p->rt.rt_rq = tg->rt_rq[cpu];
1510 p->rt.parent = tg->rt_se[cpu];
1511#endif
1512}
1513
1514#else /* CONFIG_CGROUP_SCHED */
1515
1516static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
1517static inline struct task_group *task_group(struct task_struct *p)
1518{
1519 return NULL;
1520}
1521
1522#endif /* CONFIG_CGROUP_SCHED */
1523
1524static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
1525{
1526 set_task_rq(p, cpu);
1527#ifdef CONFIG_SMP
1528 /*
1529 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
1530 * successfully executed on another CPU. We must ensure that updates of
1531 * per-task data have been completed by this moment.
1532 */
1533 smp_wmb();
1534#ifdef CONFIG_THREAD_INFO_IN_TASK
1535 WRITE_ONCE(p->cpu, cpu);
1536#else
1537 WRITE_ONCE(task_thread_info(p)->cpu, cpu);
1538#endif
1539 p->wake_cpu = cpu;
1540#endif
1541}
1542
1543/*
1544 * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
1545 */
1546#ifdef CONFIG_SCHED_DEBUG
1547# include <linux/static_key.h>
1548# define const_debug __read_mostly
1549#else
1550# define const_debug const
1551#endif
1552
1553#define SCHED_FEAT(name, enabled) \
1554 __SCHED_FEAT_##name ,
1555
1556enum {
1557#include "features.h"
1558 __SCHED_FEAT_NR,
1559};
1560
1561#undef SCHED_FEAT
1562
1563#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_JUMP_LABEL)
1564
1565/*
1566 * To support run-time toggling of sched features, all the translation units
1567 * (but core.c) reference the sysctl_sched_features defined in core.c.
1568 */
1569extern const_debug unsigned int sysctl_sched_features;
1570
1571#define SCHED_FEAT(name, enabled) \
1572static __always_inline bool static_branch_##name(struct static_key *key) \
1573{ \
1574 return static_key_##enabled(key); \
1575}
1576
1577#include "features.h"
1578#undef SCHED_FEAT
1579
1580extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
1581#define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
1582
1583#else /* !(SCHED_DEBUG && CONFIG_JUMP_LABEL) */
1584
1585/*
1586 * Each translation unit has its own copy of sysctl_sched_features to allow
1587 * constants propagation at compile time and compiler optimization based on
1588 * features default.
1589 */
1590#define SCHED_FEAT(name, enabled) \
1591 (1UL << __SCHED_FEAT_##name) * enabled |
1592static const_debug __maybe_unused unsigned int sysctl_sched_features =
1593#include "features.h"
1594 0;
1595#undef SCHED_FEAT
1596
1597#define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1598
1599#endif /* SCHED_DEBUG && CONFIG_JUMP_LABEL */
1600
1601extern struct static_key_false sched_numa_balancing;
1602extern struct static_key_false sched_schedstats;
1603
1604static inline u64 global_rt_period(void)
1605{
1606 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
1607}
1608
1609static inline u64 global_rt_runtime(void)
1610{
1611 if (sysctl_sched_rt_runtime < 0)
1612 return RUNTIME_INF;
1613
1614 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
1615}
1616
1617static inline int task_current(struct rq *rq, struct task_struct *p)
1618{
1619 return rq->curr == p;
1620}
1621
1622static inline int task_running(struct rq *rq, struct task_struct *p)
1623{
1624#ifdef CONFIG_SMP
1625 return p->on_cpu;
1626#else
1627 return task_current(rq, p);
1628#endif
1629}
1630
1631static inline int task_on_rq_queued(struct task_struct *p)
1632{
1633 return p->on_rq == TASK_ON_RQ_QUEUED;
1634}
1635
1636static inline int task_on_rq_migrating(struct task_struct *p)
1637{
1638 return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
1639}
1640
1641/*
1642 * wake flags
1643 */
1644#define WF_SYNC 0x01 /* Waker goes to sleep after wakeup */
1645#define WF_FORK 0x02 /* Child wakeup after fork */
1646#define WF_MIGRATED 0x4 /* Internal use, task got migrated */
1647
1648/*
1649 * To aid in avoiding the subversion of "niceness" due to uneven distribution
1650 * of tasks with abnormal "nice" values across CPUs the contribution that
1651 * each task makes to its run queue's load is weighted according to its
1652 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
1653 * scaled version of the new time slice allocation that they receive on time
1654 * slice expiry etc.
1655 */
1656
1657#define WEIGHT_IDLEPRIO 3
1658#define WMULT_IDLEPRIO 1431655765
1659
1660extern const int sched_prio_to_weight[40];
1661extern const u32 sched_prio_to_wmult[40];
1662
1663/*
1664 * {de,en}queue flags:
1665 *
1666 * DEQUEUE_SLEEP - task is no longer runnable
1667 * ENQUEUE_WAKEUP - task just became runnable
1668 *
1669 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
1670 * are in a known state which allows modification. Such pairs
1671 * should preserve as much state as possible.
1672 *
1673 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
1674 * in the runqueue.
1675 *
1676 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified)
1677 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
1678 * ENQUEUE_MIGRATED - the task was migrated during wakeup
1679 *
1680 */
1681
1682#define DEQUEUE_SLEEP 0x01
1683#define DEQUEUE_SAVE 0x02 /* Matches ENQUEUE_RESTORE */
1684#define DEQUEUE_MOVE 0x04 /* Matches ENQUEUE_MOVE */
1685#define DEQUEUE_NOCLOCK 0x08 /* Matches ENQUEUE_NOCLOCK */
1686
1687#define ENQUEUE_WAKEUP 0x01
1688#define ENQUEUE_RESTORE 0x02
1689#define ENQUEUE_MOVE 0x04
1690#define ENQUEUE_NOCLOCK 0x08
1691
1692#define ENQUEUE_HEAD 0x10
1693#define ENQUEUE_REPLENISH 0x20
1694#ifdef CONFIG_SMP
1695#define ENQUEUE_MIGRATED 0x40
1696#else
1697#define ENQUEUE_MIGRATED 0x00
1698#endif
1699
1700#define RETRY_TASK ((void *)-1UL)
1701
1702struct sched_class {
1703 const struct sched_class *next;
1704
1705#ifdef CONFIG_UCLAMP_TASK
1706 int uclamp_enabled;
1707#endif
1708
1709 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1710 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1711 void (*yield_task) (struct rq *rq);
1712 bool (*yield_to_task)(struct rq *rq, struct task_struct *p, bool preempt);
1713
1714 void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags);
1715
1716 /*
1717 * Both @prev and @rf are optional and may be NULL, in which case the
1718 * caller must already have invoked put_prev_task(rq, prev, rf).
1719 *
1720 * Otherwise it is the responsibility of the pick_next_task() to call
1721 * put_prev_task() on the @prev task or something equivalent, IFF it
1722 * returns a next task.
1723 *
1724 * In that case (@rf != NULL) it may return RETRY_TASK when it finds a
1725 * higher prio class has runnable tasks.
1726 */
1727 struct task_struct * (*pick_next_task)(struct rq *rq,
1728 struct task_struct *prev,
1729 struct rq_flags *rf);
1730 void (*put_prev_task)(struct rq *rq, struct task_struct *p);
1731 void (*set_next_task)(struct rq *rq, struct task_struct *p);
1732
1733#ifdef CONFIG_SMP
1734 int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
1735 int (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
1736 void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
1737
1738 void (*task_woken)(struct rq *this_rq, struct task_struct *task);
1739
1740 void (*set_cpus_allowed)(struct task_struct *p,
1741 const struct cpumask *newmask);
1742
1743 void (*rq_online)(struct rq *rq);
1744 void (*rq_offline)(struct rq *rq);
1745#endif
1746
1747 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
1748 void (*task_fork)(struct task_struct *p);
1749 void (*task_dead)(struct task_struct *p);
1750
1751 /*
1752 * The switched_from() call is allowed to drop rq->lock, therefore we
1753 * cannot assume the switched_from/switched_to pair is serliazed by
1754 * rq->lock. They are however serialized by p->pi_lock.
1755 */
1756 void (*switched_from)(struct rq *this_rq, struct task_struct *task);
1757 void (*switched_to) (struct rq *this_rq, struct task_struct *task);
1758 void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1759 int oldprio);
1760
1761 unsigned int (*get_rr_interval)(struct rq *rq,
1762 struct task_struct *task);
1763
1764 void (*update_curr)(struct rq *rq);
1765
1766#define TASK_SET_GROUP 0
1767#define TASK_MOVE_GROUP 1
1768
1769#ifdef CONFIG_FAIR_GROUP_SCHED
1770 void (*task_change_group)(struct task_struct *p, int type);
1771#endif
1772};
1773
1774static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
1775{
1776 WARN_ON_ONCE(rq->curr != prev);
1777 prev->sched_class->put_prev_task(rq, prev);
1778}
1779
1780static inline void set_next_task(struct rq *rq, struct task_struct *next)
1781{
1782 WARN_ON_ONCE(rq->curr != next);
1783 next->sched_class->set_next_task(rq, next);
1784}
1785
1786#ifdef CONFIG_SMP
1787#define sched_class_highest (&stop_sched_class)
1788#else
1789#define sched_class_highest (&dl_sched_class)
1790#endif
1791
1792#define for_class_range(class, _from, _to) \
1793 for (class = (_from); class != (_to); class = class->next)
1794
1795#define for_each_class(class) \
1796 for_class_range(class, sched_class_highest, NULL)
1797
1798extern const struct sched_class stop_sched_class;
1799extern const struct sched_class dl_sched_class;
1800extern const struct sched_class rt_sched_class;
1801extern const struct sched_class fair_sched_class;
1802extern const struct sched_class idle_sched_class;
1803
1804static inline bool sched_stop_runnable(struct rq *rq)
1805{
1806 return rq->stop && task_on_rq_queued(rq->stop);
1807}
1808
1809static inline bool sched_dl_runnable(struct rq *rq)
1810{
1811 return rq->dl.dl_nr_running > 0;
1812}
1813
1814static inline bool sched_rt_runnable(struct rq *rq)
1815{
1816 return rq->rt.rt_queued > 0;
1817}
1818
1819static inline bool sched_fair_runnable(struct rq *rq)
1820{
1821 return rq->cfs.nr_running > 0;
1822}
1823
1824#ifdef CONFIG_SMP
1825
1826extern void update_group_capacity(struct sched_domain *sd, int cpu);
1827
1828extern void trigger_load_balance(struct rq *rq);
1829
1830extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask);
1831
1832#endif
1833
1834#ifdef CONFIG_CPU_IDLE
1835static inline void idle_set_state(struct rq *rq,
1836 struct cpuidle_state *idle_state)
1837{
1838 rq->idle_state = idle_state;
1839}
1840
1841static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1842{
1843 SCHED_WARN_ON(!rcu_read_lock_held());
1844
1845 return rq->idle_state;
1846}
1847#else
1848static inline void idle_set_state(struct rq *rq,
1849 struct cpuidle_state *idle_state)
1850{
1851}
1852
1853static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1854{
1855 return NULL;
1856}
1857#endif
1858
1859extern void schedule_idle(void);
1860
1861extern void sysrq_sched_debug_show(void);
1862extern void sched_init_granularity(void);
1863extern void update_max_interval(void);
1864
1865extern void init_sched_dl_class(void);
1866extern void init_sched_rt_class(void);
1867extern void init_sched_fair_class(void);
1868
1869extern void reweight_task(struct task_struct *p, int prio);
1870
1871extern void resched_curr(struct rq *rq);
1872extern void resched_cpu(int cpu);
1873
1874extern struct rt_bandwidth def_rt_bandwidth;
1875extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
1876
1877extern struct dl_bandwidth def_dl_bandwidth;
1878extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
1879extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
1880extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se);
1881extern void init_dl_rq_bw_ratio(struct dl_rq *dl_rq);
1882
1883#define BW_SHIFT 20
1884#define BW_UNIT (1 << BW_SHIFT)
1885#define RATIO_SHIFT 8
1886unsigned long to_ratio(u64 period, u64 runtime);
1887
1888extern void init_entity_runnable_average(struct sched_entity *se);
1889extern void post_init_entity_util_avg(struct task_struct *p);
1890
1891#ifdef CONFIG_NO_HZ_FULL
1892extern bool sched_can_stop_tick(struct rq *rq);
1893extern int __init sched_tick_offload_init(void);
1894
1895/*
1896 * Tick may be needed by tasks in the runqueue depending on their policy and
1897 * requirements. If tick is needed, lets send the target an IPI to kick it out of
1898 * nohz mode if necessary.
1899 */
1900static inline void sched_update_tick_dependency(struct rq *rq)
1901{
1902 int cpu;
1903
1904 if (!tick_nohz_full_enabled())
1905 return;
1906
1907 cpu = cpu_of(rq);
1908
1909 if (!tick_nohz_full_cpu(cpu))
1910 return;
1911
1912 if (sched_can_stop_tick(rq))
1913 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
1914 else
1915 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
1916}
1917#else
1918static inline int sched_tick_offload_init(void) { return 0; }
1919static inline void sched_update_tick_dependency(struct rq *rq) { }
1920#endif
1921
1922static inline void add_nr_running(struct rq *rq, unsigned count)
1923{
1924 unsigned prev_nr = rq->nr_running;
1925
1926 rq->nr_running = prev_nr + count;
1927
1928#ifdef CONFIG_SMP
1929 if (prev_nr < 2 && rq->nr_running >= 2) {
1930 if (!READ_ONCE(rq->rd->overload))
1931 WRITE_ONCE(rq->rd->overload, 1);
1932 }
1933#endif
1934
1935 sched_update_tick_dependency(rq);
1936}
1937
1938static inline void sub_nr_running(struct rq *rq, unsigned count)
1939{
1940 rq->nr_running -= count;
1941 /* Check if we still need preemption */
1942 sched_update_tick_dependency(rq);
1943}
1944
1945extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
1946extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
1947
1948extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
1949
1950extern const_debug unsigned int sysctl_sched_nr_migrate;
1951extern const_debug unsigned int sysctl_sched_migration_cost;
1952
1953#ifdef CONFIG_SCHED_HRTICK
1954
1955/*
1956 * Use hrtick when:
1957 * - enabled by features
1958 * - hrtimer is actually high res
1959 */
1960static inline int hrtick_enabled(struct rq *rq)
1961{
1962 if (!sched_feat(HRTICK))
1963 return 0;
1964 if (!cpu_active(cpu_of(rq)))
1965 return 0;
1966 return hrtimer_is_hres_active(&rq->hrtick_timer);
1967}
1968
1969void hrtick_start(struct rq *rq, u64 delay);
1970
1971#else
1972
1973static inline int hrtick_enabled(struct rq *rq)
1974{
1975 return 0;
1976}
1977
1978#endif /* CONFIG_SCHED_HRTICK */
1979
1980#ifndef arch_scale_freq_capacity
1981static __always_inline
1982unsigned long arch_scale_freq_capacity(int cpu)
1983{
1984 return SCHED_CAPACITY_SCALE;
1985}
1986#endif
1987
1988#ifdef CONFIG_SMP
1989#ifdef CONFIG_PREEMPTION
1990
1991static inline void double_rq_lock(struct rq *rq1, struct rq *rq2);
1992
1993/*
1994 * fair double_lock_balance: Safely acquires both rq->locks in a fair
1995 * way at the expense of forcing extra atomic operations in all
1996 * invocations. This assures that the double_lock is acquired using the
1997 * same underlying policy as the spinlock_t on this architecture, which
1998 * reduces latency compared to the unfair variant below. However, it
1999 * also adds more overhead and therefore may reduce throughput.
2000 */
2001static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2002 __releases(this_rq->lock)
2003 __acquires(busiest->lock)
2004 __acquires(this_rq->lock)
2005{
2006 raw_spin_unlock(&this_rq->lock);
2007 double_rq_lock(this_rq, busiest);
2008
2009 return 1;
2010}
2011
2012#else
2013/*
2014 * Unfair double_lock_balance: Optimizes throughput at the expense of
2015 * latency by eliminating extra atomic operations when the locks are
2016 * already in proper order on entry. This favors lower CPU-ids and will
2017 * grant the double lock to lower CPUs over higher ids under contention,
2018 * regardless of entry order into the function.
2019 */
2020static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2021 __releases(this_rq->lock)
2022 __acquires(busiest->lock)
2023 __acquires(this_rq->lock)
2024{
2025 int ret = 0;
2026
2027 if (unlikely(!raw_spin_trylock(&busiest->lock))) {
2028 if (busiest < this_rq) {
2029 raw_spin_unlock(&this_rq->lock);
2030 raw_spin_lock(&busiest->lock);
2031 raw_spin_lock_nested(&this_rq->lock,
2032 SINGLE_DEPTH_NESTING);
2033 ret = 1;
2034 } else
2035 raw_spin_lock_nested(&busiest->lock,
2036 SINGLE_DEPTH_NESTING);
2037 }
2038 return ret;
2039}
2040
2041#endif /* CONFIG_PREEMPTION */
2042
2043/*
2044 * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
2045 */
2046static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
2047{
2048 if (unlikely(!irqs_disabled())) {
2049 /* printk() doesn't work well under rq->lock */
2050 raw_spin_unlock(&this_rq->lock);
2051 BUG_ON(1);
2052 }
2053
2054 return _double_lock_balance(this_rq, busiest);
2055}
2056
2057static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
2058 __releases(busiest->lock)
2059{
2060 raw_spin_unlock(&busiest->lock);
2061 lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
2062}
2063
2064static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
2065{
2066 if (l1 > l2)
2067 swap(l1, l2);
2068
2069 spin_lock(l1);
2070 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2071}
2072
2073static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
2074{
2075 if (l1 > l2)
2076 swap(l1, l2);
2077
2078 spin_lock_irq(l1);
2079 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2080}
2081
2082static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
2083{
2084 if (l1 > l2)
2085 swap(l1, l2);
2086
2087 raw_spin_lock(l1);
2088 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2089}
2090
2091/*
2092 * double_rq_lock - safely lock two runqueues
2093 *
2094 * Note this does not disable interrupts like task_rq_lock,
2095 * you need to do so manually before calling.
2096 */
2097static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2098 __acquires(rq1->lock)
2099 __acquires(rq2->lock)
2100{
2101 BUG_ON(!irqs_disabled());
2102 if (rq1 == rq2) {
2103 raw_spin_lock(&rq1->lock);
2104 __acquire(rq2->lock); /* Fake it out ;) */
2105 } else {
2106 if (rq1 < rq2) {
2107 raw_spin_lock(&rq1->lock);
2108 raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
2109 } else {
2110 raw_spin_lock(&rq2->lock);
2111 raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
2112 }
2113 }
2114}
2115
2116/*
2117 * double_rq_unlock - safely unlock two runqueues
2118 *
2119 * Note this does not restore interrupts like task_rq_unlock,
2120 * you need to do so manually after calling.
2121 */
2122static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2123 __releases(rq1->lock)
2124 __releases(rq2->lock)
2125{
2126 raw_spin_unlock(&rq1->lock);
2127 if (rq1 != rq2)
2128 raw_spin_unlock(&rq2->lock);
2129 else
2130 __release(rq2->lock);
2131}
2132
2133extern void set_rq_online (struct rq *rq);
2134extern void set_rq_offline(struct rq *rq);
2135extern bool sched_smp_initialized;
2136
2137#else /* CONFIG_SMP */
2138
2139/*
2140 * double_rq_lock - safely lock two runqueues
2141 *
2142 * Note this does not disable interrupts like task_rq_lock,
2143 * you need to do so manually before calling.
2144 */
2145static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2146 __acquires(rq1->lock)
2147 __acquires(rq2->lock)
2148{
2149 BUG_ON(!irqs_disabled());
2150 BUG_ON(rq1 != rq2);
2151 raw_spin_lock(&rq1->lock);
2152 __acquire(rq2->lock); /* Fake it out ;) */
2153}
2154
2155/*
2156 * double_rq_unlock - safely unlock two runqueues
2157 *
2158 * Note this does not restore interrupts like task_rq_unlock,
2159 * you need to do so manually after calling.
2160 */
2161static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2162 __releases(rq1->lock)
2163 __releases(rq2->lock)
2164{
2165 BUG_ON(rq1 != rq2);
2166 raw_spin_unlock(&rq1->lock);
2167 __release(rq2->lock);
2168}
2169
2170#endif
2171
2172extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
2173extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
2174
2175#ifdef CONFIG_SCHED_DEBUG
2176extern bool sched_debug_enabled;
2177
2178extern void print_cfs_stats(struct seq_file *m, int cpu);
2179extern void print_rt_stats(struct seq_file *m, int cpu);
2180extern void print_dl_stats(struct seq_file *m, int cpu);
2181extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
2182extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
2183extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
2184#ifdef CONFIG_NUMA_BALANCING
2185extern void
2186show_numa_stats(struct task_struct *p, struct seq_file *m);
2187extern void
2188print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
2189 unsigned long tpf, unsigned long gsf, unsigned long gpf);
2190#endif /* CONFIG_NUMA_BALANCING */
2191#endif /* CONFIG_SCHED_DEBUG */
2192
2193extern void init_cfs_rq(struct cfs_rq *cfs_rq);
2194extern void init_rt_rq(struct rt_rq *rt_rq);
2195extern void init_dl_rq(struct dl_rq *dl_rq);
2196
2197extern void cfs_bandwidth_usage_inc(void);
2198extern void cfs_bandwidth_usage_dec(void);
2199
2200#ifdef CONFIG_NO_HZ_COMMON
2201#define NOHZ_BALANCE_KICK_BIT 0
2202#define NOHZ_STATS_KICK_BIT 1
2203
2204#define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT)
2205#define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT)
2206
2207#define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK)
2208
2209#define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
2210
2211extern void nohz_balance_exit_idle(struct rq *rq);
2212#else
2213static inline void nohz_balance_exit_idle(struct rq *rq) { }
2214#endif
2215
2216
2217#ifdef CONFIG_SMP
2218static inline
2219void __dl_update(struct dl_bw *dl_b, s64 bw)
2220{
2221 struct root_domain *rd = container_of(dl_b, struct root_domain, dl_bw);
2222 int i;
2223
2224 RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
2225 "sched RCU must be held");
2226 for_each_cpu_and(i, rd->span, cpu_active_mask) {
2227 struct rq *rq = cpu_rq(i);
2228
2229 rq->dl.extra_bw += bw;
2230 }
2231}
2232#else
2233static inline
2234void __dl_update(struct dl_bw *dl_b, s64 bw)
2235{
2236 struct dl_rq *dl = container_of(dl_b, struct dl_rq, dl_bw);
2237
2238 dl->extra_bw += bw;
2239}
2240#endif
2241
2242
2243#ifdef CONFIG_IRQ_TIME_ACCOUNTING
2244struct irqtime {
2245 u64 total;
2246 u64 tick_delta;
2247 u64 irq_start_time;
2248 struct u64_stats_sync sync;
2249};
2250
2251DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
2252
2253/*
2254 * Returns the irqtime minus the softirq time computed by ksoftirqd.
2255 * Otherwise ksoftirqd's sum_exec_runtime is substracted its own runtime
2256 * and never move forward.
2257 */
2258static inline u64 irq_time_read(int cpu)
2259{
2260 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
2261 unsigned int seq;
2262 u64 total;
2263
2264 do {
2265 seq = __u64_stats_fetch_begin(&irqtime->sync);
2266 total = irqtime->total;
2267 } while (__u64_stats_fetch_retry(&irqtime->sync, seq));
2268
2269 return total;
2270}
2271#endif /* CONFIG_IRQ_TIME_ACCOUNTING */
2272
2273#ifdef CONFIG_CPU_FREQ
2274DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
2275
2276/**
2277 * cpufreq_update_util - Take a note about CPU utilization changes.
2278 * @rq: Runqueue to carry out the update for.
2279 * @flags: Update reason flags.
2280 *
2281 * This function is called by the scheduler on the CPU whose utilization is
2282 * being updated.
2283 *
2284 * It can only be called from RCU-sched read-side critical sections.
2285 *
2286 * The way cpufreq is currently arranged requires it to evaluate the CPU
2287 * performance state (frequency/voltage) on a regular basis to prevent it from
2288 * being stuck in a completely inadequate performance level for too long.
2289 * That is not guaranteed to happen if the updates are only triggered from CFS
2290 * and DL, though, because they may not be coming in if only RT tasks are
2291 * active all the time (or there are RT tasks only).
2292 *
2293 * As a workaround for that issue, this function is called periodically by the
2294 * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
2295 * but that really is a band-aid. Going forward it should be replaced with
2296 * solutions targeted more specifically at RT tasks.
2297 */
2298static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
2299{
2300 struct update_util_data *data;
2301
2302 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
2303 cpu_of(rq)));
2304 if (data)
2305 data->func(data, rq_clock(rq), flags);
2306}
2307#else
2308static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
2309#endif /* CONFIG_CPU_FREQ */
2310
2311#ifdef CONFIG_UCLAMP_TASK
2312enum uclamp_id uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
2313
2314static __always_inline
2315unsigned int uclamp_util_with(struct rq *rq, unsigned int util,
2316 struct task_struct *p)
2317{
2318 unsigned int min_util = READ_ONCE(rq->uclamp[UCLAMP_MIN].value);
2319 unsigned int max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
2320
2321 if (p) {
2322 min_util = max(min_util, uclamp_eff_value(p, UCLAMP_MIN));
2323 max_util = max(max_util, uclamp_eff_value(p, UCLAMP_MAX));
2324 }
2325
2326 /*
2327 * Since CPU's {min,max}_util clamps are MAX aggregated considering
2328 * RUNNABLE tasks with _different_ clamps, we can end up with an
2329 * inversion. Fix it now when the clamps are applied.
2330 */
2331 if (unlikely(min_util >= max_util))
2332 return min_util;
2333
2334 return clamp(util, min_util, max_util);
2335}
2336
2337static inline unsigned int uclamp_util(struct rq *rq, unsigned int util)
2338{
2339 return uclamp_util_with(rq, util, NULL);
2340}
2341#else /* CONFIG_UCLAMP_TASK */
2342static inline unsigned int uclamp_util_with(struct rq *rq, unsigned int util,
2343 struct task_struct *p)
2344{
2345 return util;
2346}
2347static inline unsigned int uclamp_util(struct rq *rq, unsigned int util)
2348{
2349 return util;
2350}
2351#endif /* CONFIG_UCLAMP_TASK */
2352
2353#ifdef arch_scale_freq_capacity
2354# ifndef arch_scale_freq_invariant
2355# define arch_scale_freq_invariant() true
2356# endif
2357#else
2358# define arch_scale_freq_invariant() false
2359#endif
2360
2361#ifdef CONFIG_SMP
2362static inline unsigned long capacity_orig_of(int cpu)
2363{
2364 return cpu_rq(cpu)->cpu_capacity_orig;
2365}
2366#endif
2367
2368/**
2369 * enum schedutil_type - CPU utilization type
2370 * @FREQUENCY_UTIL: Utilization used to select frequency
2371 * @ENERGY_UTIL: Utilization used during energy calculation
2372 *
2373 * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time
2374 * need to be aggregated differently depending on the usage made of them. This
2375 * enum is used within schedutil_freq_util() to differentiate the types of
2376 * utilization expected by the callers, and adjust the aggregation accordingly.
2377 */
2378enum schedutil_type {
2379 FREQUENCY_UTIL,
2380 ENERGY_UTIL,
2381};
2382
2383#ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
2384
2385unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
2386 unsigned long max, enum schedutil_type type,
2387 struct task_struct *p);
2388
2389static inline unsigned long cpu_bw_dl(struct rq *rq)
2390{
2391 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
2392}
2393
2394static inline unsigned long cpu_util_dl(struct rq *rq)
2395{
2396 return READ_ONCE(rq->avg_dl.util_avg);
2397}
2398
2399static inline unsigned long cpu_util_cfs(struct rq *rq)
2400{
2401 unsigned long util = READ_ONCE(rq->cfs.avg.util_avg);
2402
2403 if (sched_feat(UTIL_EST)) {
2404 util = max_t(unsigned long, util,
2405 READ_ONCE(rq->cfs.avg.util_est.enqueued));
2406 }
2407
2408 return util;
2409}
2410
2411static inline unsigned long cpu_util_rt(struct rq *rq)
2412{
2413 return READ_ONCE(rq->avg_rt.util_avg);
2414}
2415#else /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
2416static inline unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
2417 unsigned long max, enum schedutil_type type,
2418 struct task_struct *p)
2419{
2420 return 0;
2421}
2422#endif /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
2423
2424#ifdef CONFIG_HAVE_SCHED_AVG_IRQ
2425static inline unsigned long cpu_util_irq(struct rq *rq)
2426{
2427 return rq->avg_irq.util_avg;
2428}
2429
2430static inline
2431unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2432{
2433 util *= (max - irq);
2434 util /= max;
2435
2436 return util;
2437
2438}
2439#else
2440static inline unsigned long cpu_util_irq(struct rq *rq)
2441{
2442 return 0;
2443}
2444
2445static inline
2446unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2447{
2448 return util;
2449}
2450#endif
2451
2452#if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
2453
2454#define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
2455
2456DECLARE_STATIC_KEY_FALSE(sched_energy_present);
2457
2458static inline bool sched_energy_enabled(void)
2459{
2460 return static_branch_unlikely(&sched_energy_present);
2461}
2462
2463#else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
2464
2465#define perf_domain_span(pd) NULL
2466static inline bool sched_energy_enabled(void) { return false; }
2467
2468#endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
2469
2470#ifdef CONFIG_MEMBARRIER
2471/*
2472 * The scheduler provides memory barriers required by membarrier between:
2473 * - prior user-space memory accesses and store to rq->membarrier_state,
2474 * - store to rq->membarrier_state and following user-space memory accesses.
2475 * In the same way it provides those guarantees around store to rq->curr.
2476 */
2477static inline void membarrier_switch_mm(struct rq *rq,
2478 struct mm_struct *prev_mm,
2479 struct mm_struct *next_mm)
2480{
2481 int membarrier_state;
2482
2483 if (prev_mm == next_mm)
2484 return;
2485
2486 membarrier_state = atomic_read(&next_mm->membarrier_state);
2487 if (READ_ONCE(rq->membarrier_state) == membarrier_state)
2488 return;
2489
2490 WRITE_ONCE(rq->membarrier_state, membarrier_state);
2491}
2492#else
2493static inline void membarrier_switch_mm(struct rq *rq,
2494 struct mm_struct *prev_mm,
2495 struct mm_struct *next_mm)
2496{
2497}
2498#endif
1
2#include <linux/sched.h>
3#include <linux/sched/sysctl.h>
4#include <linux/sched/rt.h>
5#include <linux/sched/deadline.h>
6#include <linux/mutex.h>
7#include <linux/spinlock.h>
8#include <linux/stop_machine.h>
9#include <linux/tick.h>
10#include <linux/slab.h>
11
12#include "cpupri.h"
13#include "cpudeadline.h"
14#include "cpuacct.h"
15
16struct rq;
17
18extern __read_mostly int scheduler_running;
19
20extern unsigned long calc_load_update;
21extern atomic_long_t calc_load_tasks;
22
23extern long calc_load_fold_active(struct rq *this_rq);
24extern void update_cpu_load_active(struct rq *this_rq);
25
26/*
27 * Helpers for converting nanosecond timing to jiffy resolution
28 */
29#define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
30
31/*
32 * Increase resolution of nice-level calculations for 64-bit architectures.
33 * The extra resolution improves shares distribution and load balancing of
34 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
35 * hierarchies, especially on larger systems. This is not a user-visible change
36 * and does not change the user-interface for setting shares/weights.
37 *
38 * We increase resolution only if we have enough bits to allow this increased
39 * resolution (i.e. BITS_PER_LONG > 32). The costs for increasing resolution
40 * when BITS_PER_LONG <= 32 are pretty high and the returns do not justify the
41 * increased costs.
42 */
43#if 0 /* BITS_PER_LONG > 32 -- currently broken: it increases power usage under light load */
44# define SCHED_LOAD_RESOLUTION 10
45# define scale_load(w) ((w) << SCHED_LOAD_RESOLUTION)
46# define scale_load_down(w) ((w) >> SCHED_LOAD_RESOLUTION)
47#else
48# define SCHED_LOAD_RESOLUTION 0
49# define scale_load(w) (w)
50# define scale_load_down(w) (w)
51#endif
52
53#define SCHED_LOAD_SHIFT (10 + SCHED_LOAD_RESOLUTION)
54#define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT)
55
56#define NICE_0_LOAD SCHED_LOAD_SCALE
57#define NICE_0_SHIFT SCHED_LOAD_SHIFT
58
59/*
60 * Single value that decides SCHED_DEADLINE internal math precision.
61 * 10 -> just above 1us
62 * 9 -> just above 0.5us
63 */
64#define DL_SCALE (10)
65
66/*
67 * These are the 'tuning knobs' of the scheduler:
68 */
69
70/*
71 * single value that denotes runtime == period, ie unlimited time.
72 */
73#define RUNTIME_INF ((u64)~0ULL)
74
75static inline int fair_policy(int policy)
76{
77 return policy == SCHED_NORMAL || policy == SCHED_BATCH;
78}
79
80static inline int rt_policy(int policy)
81{
82 return policy == SCHED_FIFO || policy == SCHED_RR;
83}
84
85static inline int dl_policy(int policy)
86{
87 return policy == SCHED_DEADLINE;
88}
89
90static inline int task_has_rt_policy(struct task_struct *p)
91{
92 return rt_policy(p->policy);
93}
94
95static inline int task_has_dl_policy(struct task_struct *p)
96{
97 return dl_policy(p->policy);
98}
99
100static inline bool dl_time_before(u64 a, u64 b)
101{
102 return (s64)(a - b) < 0;
103}
104
105/*
106 * Tells if entity @a should preempt entity @b.
107 */
108static inline bool
109dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
110{
111 return dl_time_before(a->deadline, b->deadline);
112}
113
114/*
115 * This is the priority-queue data structure of the RT scheduling class:
116 */
117struct rt_prio_array {
118 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
119 struct list_head queue[MAX_RT_PRIO];
120};
121
122struct rt_bandwidth {
123 /* nests inside the rq lock: */
124 raw_spinlock_t rt_runtime_lock;
125 ktime_t rt_period;
126 u64 rt_runtime;
127 struct hrtimer rt_period_timer;
128};
129/*
130 * To keep the bandwidth of -deadline tasks and groups under control
131 * we need some place where:
132 * - store the maximum -deadline bandwidth of the system (the group);
133 * - cache the fraction of that bandwidth that is currently allocated.
134 *
135 * This is all done in the data structure below. It is similar to the
136 * one used for RT-throttling (rt_bandwidth), with the main difference
137 * that, since here we are only interested in admission control, we
138 * do not decrease any runtime while the group "executes", neither we
139 * need a timer to replenish it.
140 *
141 * With respect to SMP, the bandwidth is given on a per-CPU basis,
142 * meaning that:
143 * - dl_bw (< 100%) is the bandwidth of the system (group) on each CPU;
144 * - dl_total_bw array contains, in the i-eth element, the currently
145 * allocated bandwidth on the i-eth CPU.
146 * Moreover, groups consume bandwidth on each CPU, while tasks only
147 * consume bandwidth on the CPU they're running on.
148 * Finally, dl_total_bw_cpu is used to cache the index of dl_total_bw
149 * that will be shown the next time the proc or cgroup controls will
150 * be red. It on its turn can be changed by writing on its own
151 * control.
152 */
153struct dl_bandwidth {
154 raw_spinlock_t dl_runtime_lock;
155 u64 dl_runtime;
156 u64 dl_period;
157};
158
159static inline int dl_bandwidth_enabled(void)
160{
161 return sysctl_sched_rt_runtime >= 0;
162}
163
164extern struct dl_bw *dl_bw_of(int i);
165
166struct dl_bw {
167 raw_spinlock_t lock;
168 u64 bw, total_bw;
169};
170
171extern struct mutex sched_domains_mutex;
172
173#ifdef CONFIG_CGROUP_SCHED
174
175#include <linux/cgroup.h>
176
177struct cfs_rq;
178struct rt_rq;
179
180extern struct list_head task_groups;
181
182struct cfs_bandwidth {
183#ifdef CONFIG_CFS_BANDWIDTH
184 raw_spinlock_t lock;
185 ktime_t period;
186 u64 quota, runtime;
187 s64 hierarchal_quota;
188 u64 runtime_expires;
189
190 int idle, timer_active;
191 struct hrtimer period_timer, slack_timer;
192 struct list_head throttled_cfs_rq;
193
194 /* statistics */
195 int nr_periods, nr_throttled;
196 u64 throttled_time;
197#endif
198};
199
200/* task group related information */
201struct task_group {
202 struct cgroup_subsys_state css;
203
204#ifdef CONFIG_FAIR_GROUP_SCHED
205 /* schedulable entities of this group on each cpu */
206 struct sched_entity **se;
207 /* runqueue "owned" by this group on each cpu */
208 struct cfs_rq **cfs_rq;
209 unsigned long shares;
210
211#ifdef CONFIG_SMP
212 atomic_long_t load_avg;
213 atomic_t runnable_avg;
214#endif
215#endif
216
217#ifdef CONFIG_RT_GROUP_SCHED
218 struct sched_rt_entity **rt_se;
219 struct rt_rq **rt_rq;
220
221 struct rt_bandwidth rt_bandwidth;
222#endif
223
224 struct rcu_head rcu;
225 struct list_head list;
226
227 struct task_group *parent;
228 struct list_head siblings;
229 struct list_head children;
230
231#ifdef CONFIG_SCHED_AUTOGROUP
232 struct autogroup *autogroup;
233#endif
234
235 struct cfs_bandwidth cfs_bandwidth;
236};
237
238#ifdef CONFIG_FAIR_GROUP_SCHED
239#define ROOT_TASK_GROUP_LOAD NICE_0_LOAD
240
241/*
242 * A weight of 0 or 1 can cause arithmetics problems.
243 * A weight of a cfs_rq is the sum of weights of which entities
244 * are queued on this cfs_rq, so a weight of a entity should not be
245 * too large, so as the shares value of a task group.
246 * (The default weight is 1024 - so there's no practical
247 * limitation from this.)
248 */
249#define MIN_SHARES (1UL << 1)
250#define MAX_SHARES (1UL << 18)
251#endif
252
253typedef int (*tg_visitor)(struct task_group *, void *);
254
255extern int walk_tg_tree_from(struct task_group *from,
256 tg_visitor down, tg_visitor up, void *data);
257
258/*
259 * Iterate the full tree, calling @down when first entering a node and @up when
260 * leaving it for the final time.
261 *
262 * Caller must hold rcu_lock or sufficient equivalent.
263 */
264static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
265{
266 return walk_tg_tree_from(&root_task_group, down, up, data);
267}
268
269extern int tg_nop(struct task_group *tg, void *data);
270
271extern void free_fair_sched_group(struct task_group *tg);
272extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
273extern void unregister_fair_sched_group(struct task_group *tg, int cpu);
274extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
275 struct sched_entity *se, int cpu,
276 struct sched_entity *parent);
277extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
278extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
279
280extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
281extern void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b, bool force);
282extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
283
284extern void free_rt_sched_group(struct task_group *tg);
285extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
286extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
287 struct sched_rt_entity *rt_se, int cpu,
288 struct sched_rt_entity *parent);
289
290extern struct task_group *sched_create_group(struct task_group *parent);
291extern void sched_online_group(struct task_group *tg,
292 struct task_group *parent);
293extern void sched_destroy_group(struct task_group *tg);
294extern void sched_offline_group(struct task_group *tg);
295
296extern void sched_move_task(struct task_struct *tsk);
297
298#ifdef CONFIG_FAIR_GROUP_SCHED
299extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
300#endif
301
302#else /* CONFIG_CGROUP_SCHED */
303
304struct cfs_bandwidth { };
305
306#endif /* CONFIG_CGROUP_SCHED */
307
308/* CFS-related fields in a runqueue */
309struct cfs_rq {
310 struct load_weight load;
311 unsigned int nr_running, h_nr_running;
312
313 u64 exec_clock;
314 u64 min_vruntime;
315#ifndef CONFIG_64BIT
316 u64 min_vruntime_copy;
317#endif
318
319 struct rb_root tasks_timeline;
320 struct rb_node *rb_leftmost;
321
322 /*
323 * 'curr' points to currently running entity on this cfs_rq.
324 * It is set to NULL otherwise (i.e when none are currently running).
325 */
326 struct sched_entity *curr, *next, *last, *skip;
327
328#ifdef CONFIG_SCHED_DEBUG
329 unsigned int nr_spread_over;
330#endif
331
332#ifdef CONFIG_SMP
333 /*
334 * CFS Load tracking
335 * Under CFS, load is tracked on a per-entity basis and aggregated up.
336 * This allows for the description of both thread and group usage (in
337 * the FAIR_GROUP_SCHED case).
338 */
339 unsigned long runnable_load_avg, blocked_load_avg;
340 atomic64_t decay_counter;
341 u64 last_decay;
342 atomic_long_t removed_load;
343
344#ifdef CONFIG_FAIR_GROUP_SCHED
345 /* Required to track per-cpu representation of a task_group */
346 u32 tg_runnable_contrib;
347 unsigned long tg_load_contrib;
348
349 /*
350 * h_load = weight * f(tg)
351 *
352 * Where f(tg) is the recursive weight fraction assigned to
353 * this group.
354 */
355 unsigned long h_load;
356 u64 last_h_load_update;
357 struct sched_entity *h_load_next;
358#endif /* CONFIG_FAIR_GROUP_SCHED */
359#endif /* CONFIG_SMP */
360
361#ifdef CONFIG_FAIR_GROUP_SCHED
362 struct rq *rq; /* cpu runqueue to which this cfs_rq is attached */
363
364 /*
365 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
366 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
367 * (like users, containers etc.)
368 *
369 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This
370 * list is used during load balance.
371 */
372 int on_list;
373 struct list_head leaf_cfs_rq_list;
374 struct task_group *tg; /* group that "owns" this runqueue */
375
376#ifdef CONFIG_CFS_BANDWIDTH
377 int runtime_enabled;
378 u64 runtime_expires;
379 s64 runtime_remaining;
380
381 u64 throttled_clock, throttled_clock_task;
382 u64 throttled_clock_task_time;
383 int throttled, throttle_count;
384 struct list_head throttled_list;
385#endif /* CONFIG_CFS_BANDWIDTH */
386#endif /* CONFIG_FAIR_GROUP_SCHED */
387};
388
389static inline int rt_bandwidth_enabled(void)
390{
391 return sysctl_sched_rt_runtime >= 0;
392}
393
394/* Real-Time classes' related field in a runqueue: */
395struct rt_rq {
396 struct rt_prio_array active;
397 unsigned int rt_nr_running;
398#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
399 struct {
400 int curr; /* highest queued rt task prio */
401#ifdef CONFIG_SMP
402 int next; /* next highest */
403#endif
404 } highest_prio;
405#endif
406#ifdef CONFIG_SMP
407 unsigned long rt_nr_migratory;
408 unsigned long rt_nr_total;
409 int overloaded;
410 struct plist_head pushable_tasks;
411#endif
412 int rt_throttled;
413 u64 rt_time;
414 u64 rt_runtime;
415 /* Nests inside the rq lock: */
416 raw_spinlock_t rt_runtime_lock;
417
418#ifdef CONFIG_RT_GROUP_SCHED
419 unsigned long rt_nr_boosted;
420
421 struct rq *rq;
422 struct task_group *tg;
423#endif
424};
425
426#ifdef CONFIG_RT_GROUP_SCHED
427static inline int rt_rq_throttled(struct rt_rq *rt_rq)
428{
429 return rt_rq->rt_throttled && !rt_rq->rt_nr_boosted;
430}
431#else
432static inline int rt_rq_throttled(struct rt_rq *rt_rq)
433{
434 return rt_rq->rt_throttled;
435}
436#endif
437
438/* Deadline class' related fields in a runqueue */
439struct dl_rq {
440 /* runqueue is an rbtree, ordered by deadline */
441 struct rb_root rb_root;
442 struct rb_node *rb_leftmost;
443
444 unsigned long dl_nr_running;
445
446#ifdef CONFIG_SMP
447 /*
448 * Deadline values of the currently executing and the
449 * earliest ready task on this rq. Caching these facilitates
450 * the decision wether or not a ready but not running task
451 * should migrate somewhere else.
452 */
453 struct {
454 u64 curr;
455 u64 next;
456 } earliest_dl;
457
458 unsigned long dl_nr_migratory;
459 int overloaded;
460
461 /*
462 * Tasks on this rq that can be pushed away. They are kept in
463 * an rb-tree, ordered by tasks' deadlines, with caching
464 * of the leftmost (earliest deadline) element.
465 */
466 struct rb_root pushable_dl_tasks_root;
467 struct rb_node *pushable_dl_tasks_leftmost;
468#else
469 struct dl_bw dl_bw;
470#endif
471};
472
473#ifdef CONFIG_SMP
474
475/*
476 * We add the notion of a root-domain which will be used to define per-domain
477 * variables. Each exclusive cpuset essentially defines an island domain by
478 * fully partitioning the member cpus from any other cpuset. Whenever a new
479 * exclusive cpuset is created, we also create and attach a new root-domain
480 * object.
481 *
482 */
483struct root_domain {
484 atomic_t refcount;
485 atomic_t rto_count;
486 struct rcu_head rcu;
487 cpumask_var_t span;
488 cpumask_var_t online;
489
490 /*
491 * The bit corresponding to a CPU gets set here if such CPU has more
492 * than one runnable -deadline task (as it is below for RT tasks).
493 */
494 cpumask_var_t dlo_mask;
495 atomic_t dlo_count;
496 struct dl_bw dl_bw;
497 struct cpudl cpudl;
498
499 /*
500 * The "RT overload" flag: it gets set if a CPU has more than
501 * one runnable RT task.
502 */
503 cpumask_var_t rto_mask;
504 struct cpupri cpupri;
505};
506
507extern struct root_domain def_root_domain;
508
509#endif /* CONFIG_SMP */
510
511/*
512 * This is the main, per-CPU runqueue data structure.
513 *
514 * Locking rule: those places that want to lock multiple runqueues
515 * (such as the load balancing or the thread migration code), lock
516 * acquire operations must be ordered by ascending &runqueue.
517 */
518struct rq {
519 /* runqueue lock: */
520 raw_spinlock_t lock;
521
522 /*
523 * nr_running and cpu_load should be in the same cacheline because
524 * remote CPUs use both these fields when doing load calculation.
525 */
526 unsigned int nr_running;
527#ifdef CONFIG_NUMA_BALANCING
528 unsigned int nr_numa_running;
529 unsigned int nr_preferred_running;
530#endif
531 #define CPU_LOAD_IDX_MAX 5
532 unsigned long cpu_load[CPU_LOAD_IDX_MAX];
533 unsigned long last_load_update_tick;
534#ifdef CONFIG_NO_HZ_COMMON
535 u64 nohz_stamp;
536 unsigned long nohz_flags;
537#endif
538#ifdef CONFIG_NO_HZ_FULL
539 unsigned long last_sched_tick;
540#endif
541 int skip_clock_update;
542
543 /* capture load from *all* tasks on this cpu: */
544 struct load_weight load;
545 unsigned long nr_load_updates;
546 u64 nr_switches;
547
548 struct cfs_rq cfs;
549 struct rt_rq rt;
550 struct dl_rq dl;
551
552#ifdef CONFIG_FAIR_GROUP_SCHED
553 /* list of leaf cfs_rq on this cpu: */
554 struct list_head leaf_cfs_rq_list;
555
556 struct sched_avg avg;
557#endif /* CONFIG_FAIR_GROUP_SCHED */
558
559 /*
560 * This is part of a global counter where only the total sum
561 * over all CPUs matters. A task can increase this counter on
562 * one CPU and if it got migrated afterwards it may decrease
563 * it on another CPU. Always updated under the runqueue lock:
564 */
565 unsigned long nr_uninterruptible;
566
567 struct task_struct *curr, *idle, *stop;
568 unsigned long next_balance;
569 struct mm_struct *prev_mm;
570
571 u64 clock;
572 u64 clock_task;
573
574 atomic_t nr_iowait;
575
576#ifdef CONFIG_SMP
577 struct root_domain *rd;
578 struct sched_domain *sd;
579
580 unsigned long cpu_power;
581
582 unsigned char idle_balance;
583 /* For active balancing */
584 int post_schedule;
585 int active_balance;
586 int push_cpu;
587 struct cpu_stop_work active_balance_work;
588 /* cpu of this runqueue: */
589 int cpu;
590 int online;
591
592 struct list_head cfs_tasks;
593
594 u64 rt_avg;
595 u64 age_stamp;
596 u64 idle_stamp;
597 u64 avg_idle;
598
599 /* This is used to determine avg_idle's max value */
600 u64 max_idle_balance_cost;
601#endif
602
603#ifdef CONFIG_IRQ_TIME_ACCOUNTING
604 u64 prev_irq_time;
605#endif
606#ifdef CONFIG_PARAVIRT
607 u64 prev_steal_time;
608#endif
609#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
610 u64 prev_steal_time_rq;
611#endif
612
613 /* calc_load related fields */
614 unsigned long calc_load_update;
615 long calc_load_active;
616
617#ifdef CONFIG_SCHED_HRTICK
618#ifdef CONFIG_SMP
619 int hrtick_csd_pending;
620 struct call_single_data hrtick_csd;
621#endif
622 struct hrtimer hrtick_timer;
623#endif
624
625#ifdef CONFIG_SCHEDSTATS
626 /* latency stats */
627 struct sched_info rq_sched_info;
628 unsigned long long rq_cpu_time;
629 /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
630
631 /* sys_sched_yield() stats */
632 unsigned int yld_count;
633
634 /* schedule() stats */
635 unsigned int sched_count;
636 unsigned int sched_goidle;
637
638 /* try_to_wake_up() stats */
639 unsigned int ttwu_count;
640 unsigned int ttwu_local;
641#endif
642
643#ifdef CONFIG_SMP
644 struct llist_head wake_list;
645#endif
646};
647
648static inline int cpu_of(struct rq *rq)
649{
650#ifdef CONFIG_SMP
651 return rq->cpu;
652#else
653 return 0;
654#endif
655}
656
657DECLARE_PER_CPU(struct rq, runqueues);
658
659#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
660#define this_rq() (&__get_cpu_var(runqueues))
661#define task_rq(p) cpu_rq(task_cpu(p))
662#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
663#define raw_rq() (&__raw_get_cpu_var(runqueues))
664
665static inline u64 rq_clock(struct rq *rq)
666{
667 return rq->clock;
668}
669
670static inline u64 rq_clock_task(struct rq *rq)
671{
672 return rq->clock_task;
673}
674
675#ifdef CONFIG_NUMA_BALANCING
676extern void sched_setnuma(struct task_struct *p, int node);
677extern int migrate_task_to(struct task_struct *p, int cpu);
678extern int migrate_swap(struct task_struct *, struct task_struct *);
679#endif /* CONFIG_NUMA_BALANCING */
680
681#ifdef CONFIG_SMP
682
683#define rcu_dereference_check_sched_domain(p) \
684 rcu_dereference_check((p), \
685 lockdep_is_held(&sched_domains_mutex))
686
687/*
688 * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
689 * See detach_destroy_domains: synchronize_sched for details.
690 *
691 * The domain tree of any CPU may only be accessed from within
692 * preempt-disabled sections.
693 */
694#define for_each_domain(cpu, __sd) \
695 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
696 __sd; __sd = __sd->parent)
697
698#define for_each_lower_domain(sd) for (; sd; sd = sd->child)
699
700/**
701 * highest_flag_domain - Return highest sched_domain containing flag.
702 * @cpu: The cpu whose highest level of sched domain is to
703 * be returned.
704 * @flag: The flag to check for the highest sched_domain
705 * for the given cpu.
706 *
707 * Returns the highest sched_domain of a cpu which contains the given flag.
708 */
709static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
710{
711 struct sched_domain *sd, *hsd = NULL;
712
713 for_each_domain(cpu, sd) {
714 if (!(sd->flags & flag))
715 break;
716 hsd = sd;
717 }
718
719 return hsd;
720}
721
722static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
723{
724 struct sched_domain *sd;
725
726 for_each_domain(cpu, sd) {
727 if (sd->flags & flag)
728 break;
729 }
730
731 return sd;
732}
733
734DECLARE_PER_CPU(struct sched_domain *, sd_llc);
735DECLARE_PER_CPU(int, sd_llc_size);
736DECLARE_PER_CPU(int, sd_llc_id);
737DECLARE_PER_CPU(struct sched_domain *, sd_numa);
738DECLARE_PER_CPU(struct sched_domain *, sd_busy);
739DECLARE_PER_CPU(struct sched_domain *, sd_asym);
740
741struct sched_group_power {
742 atomic_t ref;
743 /*
744 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
745 * single CPU.
746 */
747 unsigned int power, power_orig;
748 unsigned long next_update;
749 int imbalance; /* XXX unrelated to power but shared group state */
750 /*
751 * Number of busy cpus in this group.
752 */
753 atomic_t nr_busy_cpus;
754
755 unsigned long cpumask[0]; /* iteration mask */
756};
757
758struct sched_group {
759 struct sched_group *next; /* Must be a circular list */
760 atomic_t ref;
761
762 unsigned int group_weight;
763 struct sched_group_power *sgp;
764
765 /*
766 * The CPUs this group covers.
767 *
768 * NOTE: this field is variable length. (Allocated dynamically
769 * by attaching extra space to the end of the structure,
770 * depending on how many CPUs the kernel has booted up with)
771 */
772 unsigned long cpumask[0];
773};
774
775static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
776{
777 return to_cpumask(sg->cpumask);
778}
779
780/*
781 * cpumask masking which cpus in the group are allowed to iterate up the domain
782 * tree.
783 */
784static inline struct cpumask *sched_group_mask(struct sched_group *sg)
785{
786 return to_cpumask(sg->sgp->cpumask);
787}
788
789/**
790 * group_first_cpu - Returns the first cpu in the cpumask of a sched_group.
791 * @group: The group whose first cpu is to be returned.
792 */
793static inline unsigned int group_first_cpu(struct sched_group *group)
794{
795 return cpumask_first(sched_group_cpus(group));
796}
797
798extern int group_balance_cpu(struct sched_group *sg);
799
800#endif /* CONFIG_SMP */
801
802#include "stats.h"
803#include "auto_group.h"
804
805#ifdef CONFIG_CGROUP_SCHED
806
807/*
808 * Return the group to which this tasks belongs.
809 *
810 * We cannot use task_css() and friends because the cgroup subsystem
811 * changes that value before the cgroup_subsys::attach() method is called,
812 * therefore we cannot pin it and might observe the wrong value.
813 *
814 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
815 * core changes this before calling sched_move_task().
816 *
817 * Instead we use a 'copy' which is updated from sched_move_task() while
818 * holding both task_struct::pi_lock and rq::lock.
819 */
820static inline struct task_group *task_group(struct task_struct *p)
821{
822 return p->sched_task_group;
823}
824
825/* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
826static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
827{
828#if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
829 struct task_group *tg = task_group(p);
830#endif
831
832#ifdef CONFIG_FAIR_GROUP_SCHED
833 p->se.cfs_rq = tg->cfs_rq[cpu];
834 p->se.parent = tg->se[cpu];
835#endif
836
837#ifdef CONFIG_RT_GROUP_SCHED
838 p->rt.rt_rq = tg->rt_rq[cpu];
839 p->rt.parent = tg->rt_se[cpu];
840#endif
841}
842
843#else /* CONFIG_CGROUP_SCHED */
844
845static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
846static inline struct task_group *task_group(struct task_struct *p)
847{
848 return NULL;
849}
850
851#endif /* CONFIG_CGROUP_SCHED */
852
853static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
854{
855 set_task_rq(p, cpu);
856#ifdef CONFIG_SMP
857 /*
858 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
859 * successfuly executed on another CPU. We must ensure that updates of
860 * per-task data have been completed by this moment.
861 */
862 smp_wmb();
863 task_thread_info(p)->cpu = cpu;
864 p->wake_cpu = cpu;
865#endif
866}
867
868/*
869 * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
870 */
871#ifdef CONFIG_SCHED_DEBUG
872# include <linux/static_key.h>
873# define const_debug __read_mostly
874#else
875# define const_debug const
876#endif
877
878extern const_debug unsigned int sysctl_sched_features;
879
880#define SCHED_FEAT(name, enabled) \
881 __SCHED_FEAT_##name ,
882
883enum {
884#include "features.h"
885 __SCHED_FEAT_NR,
886};
887
888#undef SCHED_FEAT
889
890#if defined(CONFIG_SCHED_DEBUG) && defined(HAVE_JUMP_LABEL)
891static __always_inline bool static_branch__true(struct static_key *key)
892{
893 return static_key_true(key); /* Not out of line branch. */
894}
895
896static __always_inline bool static_branch__false(struct static_key *key)
897{
898 return static_key_false(key); /* Out of line branch. */
899}
900
901#define SCHED_FEAT(name, enabled) \
902static __always_inline bool static_branch_##name(struct static_key *key) \
903{ \
904 return static_branch__##enabled(key); \
905}
906
907#include "features.h"
908
909#undef SCHED_FEAT
910
911extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
912#define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
913#else /* !(SCHED_DEBUG && HAVE_JUMP_LABEL) */
914#define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
915#endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */
916
917#ifdef CONFIG_NUMA_BALANCING
918#define sched_feat_numa(x) sched_feat(x)
919#ifdef CONFIG_SCHED_DEBUG
920#define numabalancing_enabled sched_feat_numa(NUMA)
921#else
922extern bool numabalancing_enabled;
923#endif /* CONFIG_SCHED_DEBUG */
924#else
925#define sched_feat_numa(x) (0)
926#define numabalancing_enabled (0)
927#endif /* CONFIG_NUMA_BALANCING */
928
929static inline u64 global_rt_period(void)
930{
931 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
932}
933
934static inline u64 global_rt_runtime(void)
935{
936 if (sysctl_sched_rt_runtime < 0)
937 return RUNTIME_INF;
938
939 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
940}
941
942static inline int task_current(struct rq *rq, struct task_struct *p)
943{
944 return rq->curr == p;
945}
946
947static inline int task_running(struct rq *rq, struct task_struct *p)
948{
949#ifdef CONFIG_SMP
950 return p->on_cpu;
951#else
952 return task_current(rq, p);
953#endif
954}
955
956
957#ifndef prepare_arch_switch
958# define prepare_arch_switch(next) do { } while (0)
959#endif
960#ifndef finish_arch_switch
961# define finish_arch_switch(prev) do { } while (0)
962#endif
963#ifndef finish_arch_post_lock_switch
964# define finish_arch_post_lock_switch() do { } while (0)
965#endif
966
967#ifndef __ARCH_WANT_UNLOCKED_CTXSW
968static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
969{
970#ifdef CONFIG_SMP
971 /*
972 * We can optimise this out completely for !SMP, because the
973 * SMP rebalancing from interrupt is the only thing that cares
974 * here.
975 */
976 next->on_cpu = 1;
977#endif
978}
979
980static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
981{
982#ifdef CONFIG_SMP
983 /*
984 * After ->on_cpu is cleared, the task can be moved to a different CPU.
985 * We must ensure this doesn't happen until the switch is completely
986 * finished.
987 */
988 smp_wmb();
989 prev->on_cpu = 0;
990#endif
991#ifdef CONFIG_DEBUG_SPINLOCK
992 /* this is a valid case when another task releases the spinlock */
993 rq->lock.owner = current;
994#endif
995 /*
996 * If we are tracking spinlock dependencies then we have to
997 * fix up the runqueue lock - which gets 'carried over' from
998 * prev into current:
999 */
1000 spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_);
1001
1002 raw_spin_unlock_irq(&rq->lock);
1003}
1004
1005#else /* __ARCH_WANT_UNLOCKED_CTXSW */
1006static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
1007{
1008#ifdef CONFIG_SMP
1009 /*
1010 * We can optimise this out completely for !SMP, because the
1011 * SMP rebalancing from interrupt is the only thing that cares
1012 * here.
1013 */
1014 next->on_cpu = 1;
1015#endif
1016 raw_spin_unlock(&rq->lock);
1017}
1018
1019static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
1020{
1021#ifdef CONFIG_SMP
1022 /*
1023 * After ->on_cpu is cleared, the task can be moved to a different CPU.
1024 * We must ensure this doesn't happen until the switch is completely
1025 * finished.
1026 */
1027 smp_wmb();
1028 prev->on_cpu = 0;
1029#endif
1030 local_irq_enable();
1031}
1032#endif /* __ARCH_WANT_UNLOCKED_CTXSW */
1033
1034/*
1035 * wake flags
1036 */
1037#define WF_SYNC 0x01 /* waker goes to sleep after wakeup */
1038#define WF_FORK 0x02 /* child wakeup after fork */
1039#define WF_MIGRATED 0x4 /* internal use, task got migrated */
1040
1041/*
1042 * To aid in avoiding the subversion of "niceness" due to uneven distribution
1043 * of tasks with abnormal "nice" values across CPUs the contribution that
1044 * each task makes to its run queue's load is weighted according to its
1045 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
1046 * scaled version of the new time slice allocation that they receive on time
1047 * slice expiry etc.
1048 */
1049
1050#define WEIGHT_IDLEPRIO 3
1051#define WMULT_IDLEPRIO 1431655765
1052
1053/*
1054 * Nice levels are multiplicative, with a gentle 10% change for every
1055 * nice level changed. I.e. when a CPU-bound task goes from nice 0 to
1056 * nice 1, it will get ~10% less CPU time than another CPU-bound task
1057 * that remained on nice 0.
1058 *
1059 * The "10% effect" is relative and cumulative: from _any_ nice level,
1060 * if you go up 1 level, it's -10% CPU usage, if you go down 1 level
1061 * it's +10% CPU usage. (to achieve that we use a multiplier of 1.25.
1062 * If a task goes up by ~10% and another task goes down by ~10% then
1063 * the relative distance between them is ~25%.)
1064 */
1065static const int prio_to_weight[40] = {
1066 /* -20 */ 88761, 71755, 56483, 46273, 36291,
1067 /* -15 */ 29154, 23254, 18705, 14949, 11916,
1068 /* -10 */ 9548, 7620, 6100, 4904, 3906,
1069 /* -5 */ 3121, 2501, 1991, 1586, 1277,
1070 /* 0 */ 1024, 820, 655, 526, 423,
1071 /* 5 */ 335, 272, 215, 172, 137,
1072 /* 10 */ 110, 87, 70, 56, 45,
1073 /* 15 */ 36, 29, 23, 18, 15,
1074};
1075
1076/*
1077 * Inverse (2^32/x) values of the prio_to_weight[] array, precalculated.
1078 *
1079 * In cases where the weight does not change often, we can use the
1080 * precalculated inverse to speed up arithmetics by turning divisions
1081 * into multiplications:
1082 */
1083static const u32 prio_to_wmult[40] = {
1084 /* -20 */ 48388, 59856, 76040, 92818, 118348,
1085 /* -15 */ 147320, 184698, 229616, 287308, 360437,
1086 /* -10 */ 449829, 563644, 704093, 875809, 1099582,
1087 /* -5 */ 1376151, 1717300, 2157191, 2708050, 3363326,
1088 /* 0 */ 4194304, 5237765, 6557202, 8165337, 10153587,
1089 /* 5 */ 12820798, 15790321, 19976592, 24970740, 31350126,
1090 /* 10 */ 39045157, 49367440, 61356676, 76695844, 95443717,
1091 /* 15 */ 119304647, 148102320, 186737708, 238609294, 286331153,
1092};
1093
1094#define ENQUEUE_WAKEUP 1
1095#define ENQUEUE_HEAD 2
1096#ifdef CONFIG_SMP
1097#define ENQUEUE_WAKING 4 /* sched_class::task_waking was called */
1098#else
1099#define ENQUEUE_WAKING 0
1100#endif
1101#define ENQUEUE_REPLENISH 8
1102
1103#define DEQUEUE_SLEEP 1
1104
1105#define RETRY_TASK ((void *)-1UL)
1106
1107struct sched_class {
1108 const struct sched_class *next;
1109
1110 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1111 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1112 void (*yield_task) (struct rq *rq);
1113 bool (*yield_to_task) (struct rq *rq, struct task_struct *p, bool preempt);
1114
1115 void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
1116
1117 /*
1118 * It is the responsibility of the pick_next_task() method that will
1119 * return the next task to call put_prev_task() on the @prev task or
1120 * something equivalent.
1121 *
1122 * May return RETRY_TASK when it finds a higher prio class has runnable
1123 * tasks.
1124 */
1125 struct task_struct * (*pick_next_task) (struct rq *rq,
1126 struct task_struct *prev);
1127 void (*put_prev_task) (struct rq *rq, struct task_struct *p);
1128
1129#ifdef CONFIG_SMP
1130 int (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
1131 void (*migrate_task_rq)(struct task_struct *p, int next_cpu);
1132
1133 void (*post_schedule) (struct rq *this_rq);
1134 void (*task_waking) (struct task_struct *task);
1135 void (*task_woken) (struct rq *this_rq, struct task_struct *task);
1136
1137 void (*set_cpus_allowed)(struct task_struct *p,
1138 const struct cpumask *newmask);
1139
1140 void (*rq_online)(struct rq *rq);
1141 void (*rq_offline)(struct rq *rq);
1142#endif
1143
1144 void (*set_curr_task) (struct rq *rq);
1145 void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1146 void (*task_fork) (struct task_struct *p);
1147 void (*task_dead) (struct task_struct *p);
1148
1149 void (*switched_from) (struct rq *this_rq, struct task_struct *task);
1150 void (*switched_to) (struct rq *this_rq, struct task_struct *task);
1151 void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1152 int oldprio);
1153
1154 unsigned int (*get_rr_interval) (struct rq *rq,
1155 struct task_struct *task);
1156
1157#ifdef CONFIG_FAIR_GROUP_SCHED
1158 void (*task_move_group) (struct task_struct *p, int on_rq);
1159#endif
1160};
1161
1162static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
1163{
1164 prev->sched_class->put_prev_task(rq, prev);
1165}
1166
1167#define sched_class_highest (&stop_sched_class)
1168#define for_each_class(class) \
1169 for (class = sched_class_highest; class; class = class->next)
1170
1171extern const struct sched_class stop_sched_class;
1172extern const struct sched_class dl_sched_class;
1173extern const struct sched_class rt_sched_class;
1174extern const struct sched_class fair_sched_class;
1175extern const struct sched_class idle_sched_class;
1176
1177
1178#ifdef CONFIG_SMP
1179
1180extern void update_group_power(struct sched_domain *sd, int cpu);
1181
1182extern void trigger_load_balance(struct rq *rq);
1183
1184extern void idle_enter_fair(struct rq *this_rq);
1185extern void idle_exit_fair(struct rq *this_rq);
1186
1187#else
1188
1189static inline void idle_enter_fair(struct rq *rq) { }
1190static inline void idle_exit_fair(struct rq *rq) { }
1191
1192#endif
1193
1194extern void sysrq_sched_debug_show(void);
1195extern void sched_init_granularity(void);
1196extern void update_max_interval(void);
1197
1198extern void init_sched_dl_class(void);
1199extern void init_sched_rt_class(void);
1200extern void init_sched_fair_class(void);
1201extern void init_sched_dl_class(void);
1202
1203extern void resched_task(struct task_struct *p);
1204extern void resched_cpu(int cpu);
1205
1206extern struct rt_bandwidth def_rt_bandwidth;
1207extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
1208
1209extern struct dl_bandwidth def_dl_bandwidth;
1210extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
1211extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
1212
1213unsigned long to_ratio(u64 period, u64 runtime);
1214
1215extern void update_idle_cpu_load(struct rq *this_rq);
1216
1217extern void init_task_runnable_average(struct task_struct *p);
1218
1219static inline void inc_nr_running(struct rq *rq)
1220{
1221 rq->nr_running++;
1222
1223#ifdef CONFIG_NO_HZ_FULL
1224 if (rq->nr_running == 2) {
1225 if (tick_nohz_full_cpu(rq->cpu)) {
1226 /* Order rq->nr_running write against the IPI */
1227 smp_wmb();
1228 smp_send_reschedule(rq->cpu);
1229 }
1230 }
1231#endif
1232}
1233
1234static inline void dec_nr_running(struct rq *rq)
1235{
1236 rq->nr_running--;
1237}
1238
1239static inline void rq_last_tick_reset(struct rq *rq)
1240{
1241#ifdef CONFIG_NO_HZ_FULL
1242 rq->last_sched_tick = jiffies;
1243#endif
1244}
1245
1246extern void update_rq_clock(struct rq *rq);
1247
1248extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
1249extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
1250
1251extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
1252
1253extern const_debug unsigned int sysctl_sched_time_avg;
1254extern const_debug unsigned int sysctl_sched_nr_migrate;
1255extern const_debug unsigned int sysctl_sched_migration_cost;
1256
1257static inline u64 sched_avg_period(void)
1258{
1259 return (u64)sysctl_sched_time_avg * NSEC_PER_MSEC / 2;
1260}
1261
1262#ifdef CONFIG_SCHED_HRTICK
1263
1264/*
1265 * Use hrtick when:
1266 * - enabled by features
1267 * - hrtimer is actually high res
1268 */
1269static inline int hrtick_enabled(struct rq *rq)
1270{
1271 if (!sched_feat(HRTICK))
1272 return 0;
1273 if (!cpu_active(cpu_of(rq)))
1274 return 0;
1275 return hrtimer_is_hres_active(&rq->hrtick_timer);
1276}
1277
1278void hrtick_start(struct rq *rq, u64 delay);
1279
1280#else
1281
1282static inline int hrtick_enabled(struct rq *rq)
1283{
1284 return 0;
1285}
1286
1287#endif /* CONFIG_SCHED_HRTICK */
1288
1289#ifdef CONFIG_SMP
1290extern void sched_avg_update(struct rq *rq);
1291static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
1292{
1293 rq->rt_avg += rt_delta;
1294 sched_avg_update(rq);
1295}
1296#else
1297static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { }
1298static inline void sched_avg_update(struct rq *rq) { }
1299#endif
1300
1301extern void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period);
1302
1303#ifdef CONFIG_SMP
1304#ifdef CONFIG_PREEMPT
1305
1306static inline void double_rq_lock(struct rq *rq1, struct rq *rq2);
1307
1308/*
1309 * fair double_lock_balance: Safely acquires both rq->locks in a fair
1310 * way at the expense of forcing extra atomic operations in all
1311 * invocations. This assures that the double_lock is acquired using the
1312 * same underlying policy as the spinlock_t on this architecture, which
1313 * reduces latency compared to the unfair variant below. However, it
1314 * also adds more overhead and therefore may reduce throughput.
1315 */
1316static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1317 __releases(this_rq->lock)
1318 __acquires(busiest->lock)
1319 __acquires(this_rq->lock)
1320{
1321 raw_spin_unlock(&this_rq->lock);
1322 double_rq_lock(this_rq, busiest);
1323
1324 return 1;
1325}
1326
1327#else
1328/*
1329 * Unfair double_lock_balance: Optimizes throughput at the expense of
1330 * latency by eliminating extra atomic operations when the locks are
1331 * already in proper order on entry. This favors lower cpu-ids and will
1332 * grant the double lock to lower cpus over higher ids under contention,
1333 * regardless of entry order into the function.
1334 */
1335static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1336 __releases(this_rq->lock)
1337 __acquires(busiest->lock)
1338 __acquires(this_rq->lock)
1339{
1340 int ret = 0;
1341
1342 if (unlikely(!raw_spin_trylock(&busiest->lock))) {
1343 if (busiest < this_rq) {
1344 raw_spin_unlock(&this_rq->lock);
1345 raw_spin_lock(&busiest->lock);
1346 raw_spin_lock_nested(&this_rq->lock,
1347 SINGLE_DEPTH_NESTING);
1348 ret = 1;
1349 } else
1350 raw_spin_lock_nested(&busiest->lock,
1351 SINGLE_DEPTH_NESTING);
1352 }
1353 return ret;
1354}
1355
1356#endif /* CONFIG_PREEMPT */
1357
1358/*
1359 * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
1360 */
1361static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
1362{
1363 if (unlikely(!irqs_disabled())) {
1364 /* printk() doesn't work good under rq->lock */
1365 raw_spin_unlock(&this_rq->lock);
1366 BUG_ON(1);
1367 }
1368
1369 return _double_lock_balance(this_rq, busiest);
1370}
1371
1372static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
1373 __releases(busiest->lock)
1374{
1375 raw_spin_unlock(&busiest->lock);
1376 lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
1377}
1378
1379static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
1380{
1381 if (l1 > l2)
1382 swap(l1, l2);
1383
1384 spin_lock(l1);
1385 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1386}
1387
1388static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
1389{
1390 if (l1 > l2)
1391 swap(l1, l2);
1392
1393 spin_lock_irq(l1);
1394 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1395}
1396
1397static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
1398{
1399 if (l1 > l2)
1400 swap(l1, l2);
1401
1402 raw_spin_lock(l1);
1403 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1404}
1405
1406/*
1407 * double_rq_lock - safely lock two runqueues
1408 *
1409 * Note this does not disable interrupts like task_rq_lock,
1410 * you need to do so manually before calling.
1411 */
1412static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
1413 __acquires(rq1->lock)
1414 __acquires(rq2->lock)
1415{
1416 BUG_ON(!irqs_disabled());
1417 if (rq1 == rq2) {
1418 raw_spin_lock(&rq1->lock);
1419 __acquire(rq2->lock); /* Fake it out ;) */
1420 } else {
1421 if (rq1 < rq2) {
1422 raw_spin_lock(&rq1->lock);
1423 raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
1424 } else {
1425 raw_spin_lock(&rq2->lock);
1426 raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
1427 }
1428 }
1429}
1430
1431/*
1432 * double_rq_unlock - safely unlock two runqueues
1433 *
1434 * Note this does not restore interrupts like task_rq_unlock,
1435 * you need to do so manually after calling.
1436 */
1437static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
1438 __releases(rq1->lock)
1439 __releases(rq2->lock)
1440{
1441 raw_spin_unlock(&rq1->lock);
1442 if (rq1 != rq2)
1443 raw_spin_unlock(&rq2->lock);
1444 else
1445 __release(rq2->lock);
1446}
1447
1448#else /* CONFIG_SMP */
1449
1450/*
1451 * double_rq_lock - safely lock two runqueues
1452 *
1453 * Note this does not disable interrupts like task_rq_lock,
1454 * you need to do so manually before calling.
1455 */
1456static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
1457 __acquires(rq1->lock)
1458 __acquires(rq2->lock)
1459{
1460 BUG_ON(!irqs_disabled());
1461 BUG_ON(rq1 != rq2);
1462 raw_spin_lock(&rq1->lock);
1463 __acquire(rq2->lock); /* Fake it out ;) */
1464}
1465
1466/*
1467 * double_rq_unlock - safely unlock two runqueues
1468 *
1469 * Note this does not restore interrupts like task_rq_unlock,
1470 * you need to do so manually after calling.
1471 */
1472static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
1473 __releases(rq1->lock)
1474 __releases(rq2->lock)
1475{
1476 BUG_ON(rq1 != rq2);
1477 raw_spin_unlock(&rq1->lock);
1478 __release(rq2->lock);
1479}
1480
1481#endif
1482
1483extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
1484extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
1485extern void print_cfs_stats(struct seq_file *m, int cpu);
1486extern void print_rt_stats(struct seq_file *m, int cpu);
1487
1488extern void init_cfs_rq(struct cfs_rq *cfs_rq);
1489extern void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq);
1490extern void init_dl_rq(struct dl_rq *dl_rq, struct rq *rq);
1491
1492extern void cfs_bandwidth_usage_inc(void);
1493extern void cfs_bandwidth_usage_dec(void);
1494
1495#ifdef CONFIG_NO_HZ_COMMON
1496enum rq_nohz_flag_bits {
1497 NOHZ_TICK_STOPPED,
1498 NOHZ_BALANCE_KICK,
1499};
1500
1501#define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
1502#endif
1503
1504#ifdef CONFIG_IRQ_TIME_ACCOUNTING
1505
1506DECLARE_PER_CPU(u64, cpu_hardirq_time);
1507DECLARE_PER_CPU(u64, cpu_softirq_time);
1508
1509#ifndef CONFIG_64BIT
1510DECLARE_PER_CPU(seqcount_t, irq_time_seq);
1511
1512static inline void irq_time_write_begin(void)
1513{
1514 __this_cpu_inc(irq_time_seq.sequence);
1515 smp_wmb();
1516}
1517
1518static inline void irq_time_write_end(void)
1519{
1520 smp_wmb();
1521 __this_cpu_inc(irq_time_seq.sequence);
1522}
1523
1524static inline u64 irq_time_read(int cpu)
1525{
1526 u64 irq_time;
1527 unsigned seq;
1528
1529 do {
1530 seq = read_seqcount_begin(&per_cpu(irq_time_seq, cpu));
1531 irq_time = per_cpu(cpu_softirq_time, cpu) +
1532 per_cpu(cpu_hardirq_time, cpu);
1533 } while (read_seqcount_retry(&per_cpu(irq_time_seq, cpu), seq));
1534
1535 return irq_time;
1536}
1537#else /* CONFIG_64BIT */
1538static inline void irq_time_write_begin(void)
1539{
1540}
1541
1542static inline void irq_time_write_end(void)
1543{
1544}
1545
1546static inline u64 irq_time_read(int cpu)
1547{
1548 return per_cpu(cpu_softirq_time, cpu) + per_cpu(cpu_hardirq_time, cpu);
1549}
1550#endif /* CONFIG_64BIT */
1551#endif /* CONFIG_IRQ_TIME_ACCOUNTING */