sched: Aggregate load contributed by task entities on parenting cfs_rq
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / kernel / sched / sched.h
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1
2#include <linux/sched.h>
3#include <linux/mutex.h>
4#include <linux/spinlock.h>
5#include <linux/stop_machine.h>
6
391e43da 7#include "cpupri.h"
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8
9extern __read_mostly int scheduler_running;
10
11/*
12 * Convert user-nice values [ -20 ... 0 ... 19 ]
13 * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
14 * and back.
15 */
16#define NICE_TO_PRIO(nice) (MAX_RT_PRIO + (nice) + 20)
17#define PRIO_TO_NICE(prio) ((prio) - MAX_RT_PRIO - 20)
18#define TASK_NICE(p) PRIO_TO_NICE((p)->static_prio)
19
20/*
21 * 'User priority' is the nice value converted to something we
22 * can work with better when scaling various scheduler parameters,
23 * it's a [ 0 ... 39 ] range.
24 */
25#define USER_PRIO(p) ((p)-MAX_RT_PRIO)
26#define TASK_USER_PRIO(p) USER_PRIO((p)->static_prio)
27#define MAX_USER_PRIO (USER_PRIO(MAX_PRIO))
28
29/*
30 * Helpers for converting nanosecond timing to jiffy resolution
31 */
32#define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
33
34#define NICE_0_LOAD SCHED_LOAD_SCALE
35#define NICE_0_SHIFT SCHED_LOAD_SHIFT
36
37/*
38 * These are the 'tuning knobs' of the scheduler:
029632fb 39 */
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40
41/*
42 * single value that denotes runtime == period, ie unlimited time.
43 */
44#define RUNTIME_INF ((u64)~0ULL)
45
46static inline int rt_policy(int policy)
47{
48 if (policy == SCHED_FIFO || policy == SCHED_RR)
49 return 1;
50 return 0;
51}
52
53static inline int task_has_rt_policy(struct task_struct *p)
54{
55 return rt_policy(p->policy);
56}
57
58/*
59 * This is the priority-queue data structure of the RT scheduling class:
60 */
61struct rt_prio_array {
62 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
63 struct list_head queue[MAX_RT_PRIO];
64};
65
66struct rt_bandwidth {
67 /* nests inside the rq lock: */
68 raw_spinlock_t rt_runtime_lock;
69 ktime_t rt_period;
70 u64 rt_runtime;
71 struct hrtimer rt_period_timer;
72};
73
74extern struct mutex sched_domains_mutex;
75
76#ifdef CONFIG_CGROUP_SCHED
77
78#include <linux/cgroup.h>
79
80struct cfs_rq;
81struct rt_rq;
82
35cf4e50 83extern struct list_head task_groups;
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84
85struct cfs_bandwidth {
86#ifdef CONFIG_CFS_BANDWIDTH
87 raw_spinlock_t lock;
88 ktime_t period;
89 u64 quota, runtime;
90 s64 hierarchal_quota;
91 u64 runtime_expires;
92
93 int idle, timer_active;
94 struct hrtimer period_timer, slack_timer;
95 struct list_head throttled_cfs_rq;
96
97 /* statistics */
98 int nr_periods, nr_throttled;
99 u64 throttled_time;
100#endif
101};
102
103/* task group related information */
104struct task_group {
105 struct cgroup_subsys_state css;
106
107#ifdef CONFIG_FAIR_GROUP_SCHED
108 /* schedulable entities of this group on each cpu */
109 struct sched_entity **se;
110 /* runqueue "owned" by this group on each cpu */
111 struct cfs_rq **cfs_rq;
112 unsigned long shares;
113
114 atomic_t load_weight;
115#endif
116
117#ifdef CONFIG_RT_GROUP_SCHED
118 struct sched_rt_entity **rt_se;
119 struct rt_rq **rt_rq;
120
121 struct rt_bandwidth rt_bandwidth;
122#endif
123
124 struct rcu_head rcu;
125 struct list_head list;
126
127 struct task_group *parent;
128 struct list_head siblings;
129 struct list_head children;
130
131#ifdef CONFIG_SCHED_AUTOGROUP
132 struct autogroup *autogroup;
133#endif
134
135 struct cfs_bandwidth cfs_bandwidth;
136};
137
138#ifdef CONFIG_FAIR_GROUP_SCHED
139#define ROOT_TASK_GROUP_LOAD NICE_0_LOAD
140
141/*
142 * A weight of 0 or 1 can cause arithmetics problems.
143 * A weight of a cfs_rq is the sum of weights of which entities
144 * are queued on this cfs_rq, so a weight of a entity should not be
145 * too large, so as the shares value of a task group.
146 * (The default weight is 1024 - so there's no practical
147 * limitation from this.)
148 */
149#define MIN_SHARES (1UL << 1)
150#define MAX_SHARES (1UL << 18)
151#endif
152
153/* Default task group.
154 * Every task in system belong to this group at bootup.
155 */
156extern struct task_group root_task_group;
157
158typedef int (*tg_visitor)(struct task_group *, void *);
159
160extern int walk_tg_tree_from(struct task_group *from,
161 tg_visitor down, tg_visitor up, void *data);
162
163/*
164 * Iterate the full tree, calling @down when first entering a node and @up when
165 * leaving it for the final time.
166 *
167 * Caller must hold rcu_lock or sufficient equivalent.
168 */
169static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
170{
171 return walk_tg_tree_from(&root_task_group, down, up, data);
172}
173
174extern int tg_nop(struct task_group *tg, void *data);
175
176extern void free_fair_sched_group(struct task_group *tg);
177extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
178extern void unregister_fair_sched_group(struct task_group *tg, int cpu);
179extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
180 struct sched_entity *se, int cpu,
181 struct sched_entity *parent);
182extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
183extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
184
185extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
186extern void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
187extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
188
189extern void free_rt_sched_group(struct task_group *tg);
190extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
191extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
192 struct sched_rt_entity *rt_se, int cpu,
193 struct sched_rt_entity *parent);
194
195#else /* CONFIG_CGROUP_SCHED */
196
197struct cfs_bandwidth { };
198
199#endif /* CONFIG_CGROUP_SCHED */
200
201/* CFS-related fields in a runqueue */
202struct cfs_rq {
203 struct load_weight load;
c82513e5 204 unsigned int nr_running, h_nr_running;
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205
206 u64 exec_clock;
207 u64 min_vruntime;
208#ifndef CONFIG_64BIT
209 u64 min_vruntime_copy;
210#endif
211
212 struct rb_root tasks_timeline;
213 struct rb_node *rb_leftmost;
214
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215 /*
216 * 'curr' points to currently running entity on this cfs_rq.
217 * It is set to NULL otherwise (i.e when none are currently running).
218 */
219 struct sched_entity *curr, *next, *last, *skip;
220
221#ifdef CONFIG_SCHED_DEBUG
222 unsigned int nr_spread_over;
223#endif
224
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225#ifdef CONFIG_SMP
226 /*
227 * CFS Load tracking
228 * Under CFS, load is tracked on a per-entity basis and aggregated up.
229 * This allows for the description of both thread and group usage (in
230 * the FAIR_GROUP_SCHED case).
231 */
232 u64 runnable_load_avg;
233#endif
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234#ifdef CONFIG_FAIR_GROUP_SCHED
235 struct rq *rq; /* cpu runqueue to which this cfs_rq is attached */
236
237 /*
238 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
239 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
240 * (like users, containers etc.)
241 *
242 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This
243 * list is used during load balance.
244 */
245 int on_list;
246 struct list_head leaf_cfs_rq_list;
247 struct task_group *tg; /* group that "owns" this runqueue */
248
249#ifdef CONFIG_SMP
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250 /*
251 * h_load = weight * f(tg)
252 *
253 * Where f(tg) is the recursive weight fraction assigned to
254 * this group.
255 */
256 unsigned long h_load;
257
258 /*
259 * Maintaining per-cpu shares distribution for group scheduling
260 *
261 * load_stamp is the last time we updated the load average
262 * load_last is the last time we updated the load average and saw load
263 * load_unacc_exec_time is currently unaccounted execution time
264 */
265 u64 load_avg;
266 u64 load_period;
267 u64 load_stamp, load_last, load_unacc_exec_time;
268
269 unsigned long load_contribution;
270#endif /* CONFIG_SMP */
271#ifdef CONFIG_CFS_BANDWIDTH
272 int runtime_enabled;
273 u64 runtime_expires;
274 s64 runtime_remaining;
275
276 u64 throttled_timestamp;
277 int throttled, throttle_count;
278 struct list_head throttled_list;
279#endif /* CONFIG_CFS_BANDWIDTH */
280#endif /* CONFIG_FAIR_GROUP_SCHED */
281};
282
283static inline int rt_bandwidth_enabled(void)
284{
285 return sysctl_sched_rt_runtime >= 0;
286}
287
288/* Real-Time classes' related field in a runqueue: */
289struct rt_rq {
290 struct rt_prio_array active;
c82513e5 291 unsigned int rt_nr_running;
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292#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
293 struct {
294 int curr; /* highest queued rt task prio */
295#ifdef CONFIG_SMP
296 int next; /* next highest */
297#endif
298 } highest_prio;
299#endif
300#ifdef CONFIG_SMP
301 unsigned long rt_nr_migratory;
302 unsigned long rt_nr_total;
303 int overloaded;
304 struct plist_head pushable_tasks;
305#endif
306 int rt_throttled;
307 u64 rt_time;
308 u64 rt_runtime;
309 /* Nests inside the rq lock: */
310 raw_spinlock_t rt_runtime_lock;
311
312#ifdef CONFIG_RT_GROUP_SCHED
313 unsigned long rt_nr_boosted;
314
315 struct rq *rq;
316 struct list_head leaf_rt_rq_list;
317 struct task_group *tg;
318#endif
319};
320
321#ifdef CONFIG_SMP
322
323/*
324 * We add the notion of a root-domain which will be used to define per-domain
325 * variables. Each exclusive cpuset essentially defines an island domain by
326 * fully partitioning the member cpus from any other cpuset. Whenever a new
327 * exclusive cpuset is created, we also create and attach a new root-domain
328 * object.
329 *
330 */
331struct root_domain {
332 atomic_t refcount;
333 atomic_t rto_count;
334 struct rcu_head rcu;
335 cpumask_var_t span;
336 cpumask_var_t online;
337
338 /*
339 * The "RT overload" flag: it gets set if a CPU has more than
340 * one runnable RT task.
341 */
342 cpumask_var_t rto_mask;
343 struct cpupri cpupri;
344};
345
346extern struct root_domain def_root_domain;
347
348#endif /* CONFIG_SMP */
349
350/*
351 * This is the main, per-CPU runqueue data structure.
352 *
353 * Locking rule: those places that want to lock multiple runqueues
354 * (such as the load balancing or the thread migration code), lock
355 * acquire operations must be ordered by ascending &runqueue.
356 */
357struct rq {
358 /* runqueue lock: */
359 raw_spinlock_t lock;
360
361 /*
362 * nr_running and cpu_load should be in the same cacheline because
363 * remote CPUs use both these fields when doing load calculation.
364 */
c82513e5 365 unsigned int nr_running;
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366 #define CPU_LOAD_IDX_MAX 5
367 unsigned long cpu_load[CPU_LOAD_IDX_MAX];
368 unsigned long last_load_update_tick;
369#ifdef CONFIG_NO_HZ
370 u64 nohz_stamp;
1c792db7 371 unsigned long nohz_flags;
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372#endif
373 int skip_clock_update;
374
375 /* capture load from *all* tasks on this cpu: */
376 struct load_weight load;
377 unsigned long nr_load_updates;
378 u64 nr_switches;
379
380 struct cfs_rq cfs;
381 struct rt_rq rt;
382
383#ifdef CONFIG_FAIR_GROUP_SCHED
384 /* list of leaf cfs_rq on this cpu: */
385 struct list_head leaf_cfs_rq_list;
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386#ifdef CONFIG_SMP
387 unsigned long h_load_throttle;
388#endif /* CONFIG_SMP */
389#endif /* CONFIG_FAIR_GROUP_SCHED */
390
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391#ifdef CONFIG_RT_GROUP_SCHED
392 struct list_head leaf_rt_rq_list;
393#endif
394
395 /*
396 * This is part of a global counter where only the total sum
397 * over all CPUs matters. A task can increase this counter on
398 * one CPU and if it got migrated afterwards it may decrease
399 * it on another CPU. Always updated under the runqueue lock:
400 */
401 unsigned long nr_uninterruptible;
402
403 struct task_struct *curr, *idle, *stop;
404 unsigned long next_balance;
405 struct mm_struct *prev_mm;
406
407 u64 clock;
408 u64 clock_task;
409
410 atomic_t nr_iowait;
411
412#ifdef CONFIG_SMP
413 struct root_domain *rd;
414 struct sched_domain *sd;
415
416 unsigned long cpu_power;
417
418 unsigned char idle_balance;
419 /* For active balancing */
420 int post_schedule;
421 int active_balance;
422 int push_cpu;
423 struct cpu_stop_work active_balance_work;
424 /* cpu of this runqueue: */
425 int cpu;
426 int online;
427
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428 struct list_head cfs_tasks;
429
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430 u64 rt_avg;
431 u64 age_stamp;
432 u64 idle_stamp;
433 u64 avg_idle;
434#endif
435
436#ifdef CONFIG_IRQ_TIME_ACCOUNTING
437 u64 prev_irq_time;
438#endif
439#ifdef CONFIG_PARAVIRT
440 u64 prev_steal_time;
441#endif
442#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
443 u64 prev_steal_time_rq;
444#endif
445
446 /* calc_load related fields */
447 unsigned long calc_load_update;
448 long calc_load_active;
449
450#ifdef CONFIG_SCHED_HRTICK
451#ifdef CONFIG_SMP
452 int hrtick_csd_pending;
453 struct call_single_data hrtick_csd;
454#endif
455 struct hrtimer hrtick_timer;
456#endif
457
458#ifdef CONFIG_SCHEDSTATS
459 /* latency stats */
460 struct sched_info rq_sched_info;
461 unsigned long long rq_cpu_time;
462 /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
463
464 /* sys_sched_yield() stats */
465 unsigned int yld_count;
466
467 /* schedule() stats */
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468 unsigned int sched_count;
469 unsigned int sched_goidle;
470
471 /* try_to_wake_up() stats */
472 unsigned int ttwu_count;
473 unsigned int ttwu_local;
474#endif
475
476#ifdef CONFIG_SMP
477 struct llist_head wake_list;
478#endif
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479
480 struct sched_avg avg;
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481};
482
483static inline int cpu_of(struct rq *rq)
484{
485#ifdef CONFIG_SMP
486 return rq->cpu;
487#else
488 return 0;
489#endif
490}
491
492DECLARE_PER_CPU(struct rq, runqueues);
493
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494#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
495#define this_rq() (&__get_cpu_var(runqueues))
496#define task_rq(p) cpu_rq(task_cpu(p))
497#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
498#define raw_rq() (&__raw_get_cpu_var(runqueues))
499
500#ifdef CONFIG_SMP
501
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502#define rcu_dereference_check_sched_domain(p) \
503 rcu_dereference_check((p), \
504 lockdep_is_held(&sched_domains_mutex))
505
506/*
507 * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
508 * See detach_destroy_domains: synchronize_sched for details.
509 *
510 * The domain tree of any CPU may only be accessed from within
511 * preempt-disabled sections.
512 */
513#define for_each_domain(cpu, __sd) \
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514 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
515 __sd; __sd = __sd->parent)
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517#define for_each_lower_domain(sd) for (; sd; sd = sd->child)
518
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519/**
520 * highest_flag_domain - Return highest sched_domain containing flag.
521 * @cpu: The cpu whose highest level of sched domain is to
522 * be returned.
523 * @flag: The flag to check for the highest sched_domain
524 * for the given cpu.
525 *
526 * Returns the highest sched_domain of a cpu which contains the given flag.
527 */
528static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
529{
530 struct sched_domain *sd, *hsd = NULL;
531
532 for_each_domain(cpu, sd) {
533 if (!(sd->flags & flag))
534 break;
535 hsd = sd;
536 }
537
538 return hsd;
539}
540
541DECLARE_PER_CPU(struct sched_domain *, sd_llc);
542DECLARE_PER_CPU(int, sd_llc_id);
543
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544extern int group_balance_cpu(struct sched_group *sg);
545
518cd623 546#endif /* CONFIG_SMP */
029632fb 547
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548#include "stats.h"
549#include "auto_group.h"
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550
551#ifdef CONFIG_CGROUP_SCHED
552
553/*
554 * Return the group to which this tasks belongs.
555 *
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556 * We cannot use task_subsys_state() and friends because the cgroup
557 * subsystem changes that value before the cgroup_subsys::attach() method
558 * is called, therefore we cannot pin it and might observe the wrong value.
559 *
560 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
561 * core changes this before calling sched_move_task().
562 *
563 * Instead we use a 'copy' which is updated from sched_move_task() while
564 * holding both task_struct::pi_lock and rq::lock.
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565 */
566static inline struct task_group *task_group(struct task_struct *p)
567{
8323f26c 568 return p->sched_task_group;
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569}
570
571/* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
572static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
573{
574#if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
575 struct task_group *tg = task_group(p);
576#endif
577
578#ifdef CONFIG_FAIR_GROUP_SCHED
579 p->se.cfs_rq = tg->cfs_rq[cpu];
580 p->se.parent = tg->se[cpu];
581#endif
582
583#ifdef CONFIG_RT_GROUP_SCHED
584 p->rt.rt_rq = tg->rt_rq[cpu];
585 p->rt.parent = tg->rt_se[cpu];
586#endif
587}
588
589#else /* CONFIG_CGROUP_SCHED */
590
591static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
592static inline struct task_group *task_group(struct task_struct *p)
593{
594 return NULL;
595}
596
597#endif /* CONFIG_CGROUP_SCHED */
598
599static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
600{
601 set_task_rq(p, cpu);
602#ifdef CONFIG_SMP
603 /*
604 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
605 * successfuly executed on another CPU. We must ensure that updates of
606 * per-task data have been completed by this moment.
607 */
608 smp_wmb();
609 task_thread_info(p)->cpu = cpu;
610#endif
611}
612
613/*
614 * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
615 */
616#ifdef CONFIG_SCHED_DEBUG
c5905afb 617# include <linux/static_key.h>
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618# define const_debug __read_mostly
619#else
620# define const_debug const
621#endif
622
623extern const_debug unsigned int sysctl_sched_features;
624
625#define SCHED_FEAT(name, enabled) \
626 __SCHED_FEAT_##name ,
627
628enum {
391e43da 629#include "features.h"
f8b6d1cc 630 __SCHED_FEAT_NR,
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631};
632
633#undef SCHED_FEAT
634
f8b6d1cc 635#if defined(CONFIG_SCHED_DEBUG) && defined(HAVE_JUMP_LABEL)
c5905afb 636static __always_inline bool static_branch__true(struct static_key *key)
f8b6d1cc 637{
c5905afb 638 return static_key_true(key); /* Not out of line branch. */
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639}
640
c5905afb 641static __always_inline bool static_branch__false(struct static_key *key)
f8b6d1cc 642{
c5905afb 643 return static_key_false(key); /* Out of line branch. */
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644}
645
646#define SCHED_FEAT(name, enabled) \
c5905afb 647static __always_inline bool static_branch_##name(struct static_key *key) \
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648{ \
649 return static_branch__##enabled(key); \
650}
651
652#include "features.h"
653
654#undef SCHED_FEAT
655
c5905afb 656extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
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657#define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
658#else /* !(SCHED_DEBUG && HAVE_JUMP_LABEL) */
029632fb 659#define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
f8b6d1cc 660#endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */
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661
662static inline u64 global_rt_period(void)
663{
664 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
665}
666
667static inline u64 global_rt_runtime(void)
668{
669 if (sysctl_sched_rt_runtime < 0)
670 return RUNTIME_INF;
671
672 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
673}
674
675
676
677static inline int task_current(struct rq *rq, struct task_struct *p)
678{
679 return rq->curr == p;
680}
681
682static inline int task_running(struct rq *rq, struct task_struct *p)
683{
684#ifdef CONFIG_SMP
685 return p->on_cpu;
686#else
687 return task_current(rq, p);
688#endif
689}
690
691
692#ifndef prepare_arch_switch
693# define prepare_arch_switch(next) do { } while (0)
694#endif
695#ifndef finish_arch_switch
696# define finish_arch_switch(prev) do { } while (0)
697#endif
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698#ifndef finish_arch_post_lock_switch
699# define finish_arch_post_lock_switch() do { } while (0)
700#endif
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701
702#ifndef __ARCH_WANT_UNLOCKED_CTXSW
703static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
704{
705#ifdef CONFIG_SMP
706 /*
707 * We can optimise this out completely for !SMP, because the
708 * SMP rebalancing from interrupt is the only thing that cares
709 * here.
710 */
711 next->on_cpu = 1;
712#endif
713}
714
715static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
716{
717#ifdef CONFIG_SMP
718 /*
719 * After ->on_cpu is cleared, the task can be moved to a different CPU.
720 * We must ensure this doesn't happen until the switch is completely
721 * finished.
722 */
723 smp_wmb();
724 prev->on_cpu = 0;
725#endif
726#ifdef CONFIG_DEBUG_SPINLOCK
727 /* this is a valid case when another task releases the spinlock */
728 rq->lock.owner = current;
729#endif
730 /*
731 * If we are tracking spinlock dependencies then we have to
732 * fix up the runqueue lock - which gets 'carried over' from
733 * prev into current:
734 */
735 spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_);
736
737 raw_spin_unlock_irq(&rq->lock);
738}
739
740#else /* __ARCH_WANT_UNLOCKED_CTXSW */
741static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
742{
743#ifdef CONFIG_SMP
744 /*
745 * We can optimise this out completely for !SMP, because the
746 * SMP rebalancing from interrupt is the only thing that cares
747 * here.
748 */
749 next->on_cpu = 1;
750#endif
029632fb 751 raw_spin_unlock(&rq->lock);
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752}
753
754static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
755{
756#ifdef CONFIG_SMP
757 /*
758 * After ->on_cpu is cleared, the task can be moved to a different CPU.
759 * We must ensure this doesn't happen until the switch is completely
760 * finished.
761 */
762 smp_wmb();
763 prev->on_cpu = 0;
764#endif
029632fb 765 local_irq_enable();
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766}
767#endif /* __ARCH_WANT_UNLOCKED_CTXSW */
768
769
770static inline void update_load_add(struct load_weight *lw, unsigned long inc)
771{
772 lw->weight += inc;
773 lw->inv_weight = 0;
774}
775
776static inline void update_load_sub(struct load_weight *lw, unsigned long dec)
777{
778 lw->weight -= dec;
779 lw->inv_weight = 0;
780}
781
782static inline void update_load_set(struct load_weight *lw, unsigned long w)
783{
784 lw->weight = w;
785 lw->inv_weight = 0;
786}
787
788/*
789 * To aid in avoiding the subversion of "niceness" due to uneven distribution
790 * of tasks with abnormal "nice" values across CPUs the contribution that
791 * each task makes to its run queue's load is weighted according to its
792 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
793 * scaled version of the new time slice allocation that they receive on time
794 * slice expiry etc.
795 */
796
797#define WEIGHT_IDLEPRIO 3
798#define WMULT_IDLEPRIO 1431655765
799
800/*
801 * Nice levels are multiplicative, with a gentle 10% change for every
802 * nice level changed. I.e. when a CPU-bound task goes from nice 0 to
803 * nice 1, it will get ~10% less CPU time than another CPU-bound task
804 * that remained on nice 0.
805 *
806 * The "10% effect" is relative and cumulative: from _any_ nice level,
807 * if you go up 1 level, it's -10% CPU usage, if you go down 1 level
808 * it's +10% CPU usage. (to achieve that we use a multiplier of 1.25.
809 * If a task goes up by ~10% and another task goes down by ~10% then
810 * the relative distance between them is ~25%.)
811 */
812static const int prio_to_weight[40] = {
813 /* -20 */ 88761, 71755, 56483, 46273, 36291,
814 /* -15 */ 29154, 23254, 18705, 14949, 11916,
815 /* -10 */ 9548, 7620, 6100, 4904, 3906,
816 /* -5 */ 3121, 2501, 1991, 1586, 1277,
817 /* 0 */ 1024, 820, 655, 526, 423,
818 /* 5 */ 335, 272, 215, 172, 137,
819 /* 10 */ 110, 87, 70, 56, 45,
820 /* 15 */ 36, 29, 23, 18, 15,
821};
822
823/*
824 * Inverse (2^32/x) values of the prio_to_weight[] array, precalculated.
825 *
826 * In cases where the weight does not change often, we can use the
827 * precalculated inverse to speed up arithmetics by turning divisions
828 * into multiplications:
829 */
830static const u32 prio_to_wmult[40] = {
831 /* -20 */ 48388, 59856, 76040, 92818, 118348,
832 /* -15 */ 147320, 184698, 229616, 287308, 360437,
833 /* -10 */ 449829, 563644, 704093, 875809, 1099582,
834 /* -5 */ 1376151, 1717300, 2157191, 2708050, 3363326,
835 /* 0 */ 4194304, 5237765, 6557202, 8165337, 10153587,
836 /* 5 */ 12820798, 15790321, 19976592, 24970740, 31350126,
837 /* 10 */ 39045157, 49367440, 61356676, 76695844, 95443717,
838 /* 15 */ 119304647, 148102320, 186737708, 238609294, 286331153,
839};
840
841/* Time spent by the tasks of the cpu accounting group executing in ... */
842enum cpuacct_stat_index {
843 CPUACCT_STAT_USER, /* ... user mode */
844 CPUACCT_STAT_SYSTEM, /* ... kernel mode */
845
846 CPUACCT_STAT_NSTATS,
847};
848
849
850#define sched_class_highest (&stop_sched_class)
851#define for_each_class(class) \
852 for (class = sched_class_highest; class; class = class->next)
853
854extern const struct sched_class stop_sched_class;
855extern const struct sched_class rt_sched_class;
856extern const struct sched_class fair_sched_class;
857extern const struct sched_class idle_sched_class;
858
859
860#ifdef CONFIG_SMP
861
862extern void trigger_load_balance(struct rq *rq, int cpu);
863extern void idle_balance(int this_cpu, struct rq *this_rq);
864
865#else /* CONFIG_SMP */
866
867static inline void idle_balance(int cpu, struct rq *rq)
868{
869}
870
871#endif
872
873extern void sysrq_sched_debug_show(void);
874extern void sched_init_granularity(void);
875extern void update_max_interval(void);
876extern void update_group_power(struct sched_domain *sd, int cpu);
877extern int update_runtime(struct notifier_block *nfb, unsigned long action, void *hcpu);
878extern void init_sched_rt_class(void);
879extern void init_sched_fair_class(void);
880
881extern void resched_task(struct task_struct *p);
882extern void resched_cpu(int cpu);
883
884extern struct rt_bandwidth def_rt_bandwidth;
885extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
886
556061b0 887extern void update_idle_cpu_load(struct rq *this_rq);
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888
889#ifdef CONFIG_CGROUP_CPUACCT
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890#include <linux/cgroup.h>
891/* track cpu usage of a group of tasks and its child groups */
892struct cpuacct {
893 struct cgroup_subsys_state css;
894 /* cpuusage holds pointer to a u64-type object on every cpu */
895 u64 __percpu *cpuusage;
896 struct kernel_cpustat __percpu *cpustat;
897};
898
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899extern struct cgroup_subsys cpuacct_subsys;
900extern struct cpuacct root_cpuacct;
901
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902/* return cpu accounting group corresponding to this container */
903static inline struct cpuacct *cgroup_ca(struct cgroup *cgrp)
904{
905 return container_of(cgroup_subsys_state(cgrp, cpuacct_subsys_id),
906 struct cpuacct, css);
907}
908
909/* return cpu accounting group to which this task belongs */
910static inline struct cpuacct *task_ca(struct task_struct *tsk)
911{
912 return container_of(task_subsys_state(tsk, cpuacct_subsys_id),
913 struct cpuacct, css);
914}
915
916static inline struct cpuacct *parent_ca(struct cpuacct *ca)
917{
918 if (!ca || !ca->css.cgroup->parent)
919 return NULL;
920 return cgroup_ca(ca->css.cgroup->parent);
921}
922
029632fb 923extern void cpuacct_charge(struct task_struct *tsk, u64 cputime);
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924#else
925static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {}
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926#endif
927
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928#ifdef CONFIG_PARAVIRT
929static inline u64 steal_ticks(u64 steal)
930{
931 if (unlikely(steal > NSEC_PER_SEC))
932 return div_u64(steal, TICK_NSEC);
933
934 return __iter_div_u64_rem(steal, TICK_NSEC, &steal);
935}
936#endif
937
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938static inline void inc_nr_running(struct rq *rq)
939{
940 rq->nr_running++;
941}
942
943static inline void dec_nr_running(struct rq *rq)
944{
945 rq->nr_running--;
946}
947
948extern void update_rq_clock(struct rq *rq);
949
950extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
951extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
952
953extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
954
955extern const_debug unsigned int sysctl_sched_time_avg;
956extern const_debug unsigned int sysctl_sched_nr_migrate;
957extern const_debug unsigned int sysctl_sched_migration_cost;
958
959static inline u64 sched_avg_period(void)
960{
961 return (u64)sysctl_sched_time_avg * NSEC_PER_MSEC / 2;
962}
963
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964#ifdef CONFIG_SCHED_HRTICK
965
966/*
967 * Use hrtick when:
968 * - enabled by features
969 * - hrtimer is actually high res
970 */
971static inline int hrtick_enabled(struct rq *rq)
972{
973 if (!sched_feat(HRTICK))
974 return 0;
975 if (!cpu_active(cpu_of(rq)))
976 return 0;
977 return hrtimer_is_hres_active(&rq->hrtick_timer);
978}
979
980void hrtick_start(struct rq *rq, u64 delay);
981
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982#else
983
984static inline int hrtick_enabled(struct rq *rq)
985{
986 return 0;
987}
988
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989#endif /* CONFIG_SCHED_HRTICK */
990
991#ifdef CONFIG_SMP
992extern void sched_avg_update(struct rq *rq);
993static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
994{
995 rq->rt_avg += rt_delta;
996 sched_avg_update(rq);
997}
998#else
999static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { }
1000static inline void sched_avg_update(struct rq *rq) { }
1001#endif
1002
1003extern void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period);
1004
1005#ifdef CONFIG_SMP
1006#ifdef CONFIG_PREEMPT
1007
1008static inline void double_rq_lock(struct rq *rq1, struct rq *rq2);
1009
1010/*
1011 * fair double_lock_balance: Safely acquires both rq->locks in a fair
1012 * way at the expense of forcing extra atomic operations in all
1013 * invocations. This assures that the double_lock is acquired using the
1014 * same underlying policy as the spinlock_t on this architecture, which
1015 * reduces latency compared to the unfair variant below. However, it
1016 * also adds more overhead and therefore may reduce throughput.
1017 */
1018static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1019 __releases(this_rq->lock)
1020 __acquires(busiest->lock)
1021 __acquires(this_rq->lock)
1022{
1023 raw_spin_unlock(&this_rq->lock);
1024 double_rq_lock(this_rq, busiest);
1025
1026 return 1;
1027}
1028
1029#else
1030/*
1031 * Unfair double_lock_balance: Optimizes throughput at the expense of
1032 * latency by eliminating extra atomic operations when the locks are
1033 * already in proper order on entry. This favors lower cpu-ids and will
1034 * grant the double lock to lower cpus over higher ids under contention,
1035 * regardless of entry order into the function.
1036 */
1037static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1038 __releases(this_rq->lock)
1039 __acquires(busiest->lock)
1040 __acquires(this_rq->lock)
1041{
1042 int ret = 0;
1043
1044 if (unlikely(!raw_spin_trylock(&busiest->lock))) {
1045 if (busiest < this_rq) {
1046 raw_spin_unlock(&this_rq->lock);
1047 raw_spin_lock(&busiest->lock);
1048 raw_spin_lock_nested(&this_rq->lock,
1049 SINGLE_DEPTH_NESTING);
1050 ret = 1;
1051 } else
1052 raw_spin_lock_nested(&busiest->lock,
1053 SINGLE_DEPTH_NESTING);
1054 }
1055 return ret;
1056}
1057
1058#endif /* CONFIG_PREEMPT */
1059
1060/*
1061 * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
1062 */
1063static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
1064{
1065 if (unlikely(!irqs_disabled())) {
1066 /* printk() doesn't work good under rq->lock */
1067 raw_spin_unlock(&this_rq->lock);
1068 BUG_ON(1);
1069 }
1070
1071 return _double_lock_balance(this_rq, busiest);
1072}
1073
1074static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
1075 __releases(busiest->lock)
1076{
1077 raw_spin_unlock(&busiest->lock);
1078 lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
1079}
1080
1081/*
1082 * double_rq_lock - safely lock two runqueues
1083 *
1084 * Note this does not disable interrupts like task_rq_lock,
1085 * you need to do so manually before calling.
1086 */
1087static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
1088 __acquires(rq1->lock)
1089 __acquires(rq2->lock)
1090{
1091 BUG_ON(!irqs_disabled());
1092 if (rq1 == rq2) {
1093 raw_spin_lock(&rq1->lock);
1094 __acquire(rq2->lock); /* Fake it out ;) */
1095 } else {
1096 if (rq1 < rq2) {
1097 raw_spin_lock(&rq1->lock);
1098 raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
1099 } else {
1100 raw_spin_lock(&rq2->lock);
1101 raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
1102 }
1103 }
1104}
1105
1106/*
1107 * double_rq_unlock - safely unlock two runqueues
1108 *
1109 * Note this does not restore interrupts like task_rq_unlock,
1110 * you need to do so manually after calling.
1111 */
1112static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
1113 __releases(rq1->lock)
1114 __releases(rq2->lock)
1115{
1116 raw_spin_unlock(&rq1->lock);
1117 if (rq1 != rq2)
1118 raw_spin_unlock(&rq2->lock);
1119 else
1120 __release(rq2->lock);
1121}
1122
1123#else /* CONFIG_SMP */
1124
1125/*
1126 * double_rq_lock - safely lock two runqueues
1127 *
1128 * Note this does not disable interrupts like task_rq_lock,
1129 * you need to do so manually before calling.
1130 */
1131static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
1132 __acquires(rq1->lock)
1133 __acquires(rq2->lock)
1134{
1135 BUG_ON(!irqs_disabled());
1136 BUG_ON(rq1 != rq2);
1137 raw_spin_lock(&rq1->lock);
1138 __acquire(rq2->lock); /* Fake it out ;) */
1139}
1140
1141/*
1142 * double_rq_unlock - safely unlock two runqueues
1143 *
1144 * Note this does not restore interrupts like task_rq_unlock,
1145 * you need to do so manually after calling.
1146 */
1147static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
1148 __releases(rq1->lock)
1149 __releases(rq2->lock)
1150{
1151 BUG_ON(rq1 != rq2);
1152 raw_spin_unlock(&rq1->lock);
1153 __release(rq2->lock);
1154}
1155
1156#endif
1157
1158extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
1159extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
1160extern void print_cfs_stats(struct seq_file *m, int cpu);
1161extern void print_rt_stats(struct seq_file *m, int cpu);
1162
1163extern void init_cfs_rq(struct cfs_rq *cfs_rq);
1164extern void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq);
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1165
1166extern void account_cfs_bandwidth_used(int enabled, int was_enabled);
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1167
1168#ifdef CONFIG_NO_HZ
1169enum rq_nohz_flag_bits {
1170 NOHZ_TICK_STOPPED,
1171 NOHZ_BALANCE_KICK,
69e1e811 1172 NOHZ_IDLE,
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1173};
1174
1175#define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
1176#endif
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1177
1178#ifdef CONFIG_IRQ_TIME_ACCOUNTING
1179
1180DECLARE_PER_CPU(u64, cpu_hardirq_time);
1181DECLARE_PER_CPU(u64, cpu_softirq_time);
1182
1183#ifndef CONFIG_64BIT
1184DECLARE_PER_CPU(seqcount_t, irq_time_seq);
1185
1186static inline void irq_time_write_begin(void)
1187{
1188 __this_cpu_inc(irq_time_seq.sequence);
1189 smp_wmb();
1190}
1191
1192static inline void irq_time_write_end(void)
1193{
1194 smp_wmb();
1195 __this_cpu_inc(irq_time_seq.sequence);
1196}
1197
1198static inline u64 irq_time_read(int cpu)
1199{
1200 u64 irq_time;
1201 unsigned seq;
1202
1203 do {
1204 seq = read_seqcount_begin(&per_cpu(irq_time_seq, cpu));
1205 irq_time = per_cpu(cpu_softirq_time, cpu) +
1206 per_cpu(cpu_hardirq_time, cpu);
1207 } while (read_seqcount_retry(&per_cpu(irq_time_seq, cpu), seq));
1208
1209 return irq_time;
1210}
1211#else /* CONFIG_64BIT */
1212static inline void irq_time_write_begin(void)
1213{
1214}
1215
1216static inline void irq_time_write_end(void)
1217{
1218}
1219
1220static inline u64 irq_time_read(int cpu)
1221{
1222 return per_cpu(cpu_softirq_time, cpu) + per_cpu(cpu_hardirq_time, cpu);
1223}
1224#endif /* CONFIG_64BIT */
1225#endif /* CONFIG_IRQ_TIME_ACCOUNTING */