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TOMOYO Linux Cross Reference
Linux/kernel/sched/sched.h

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  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/irq_work.h>
 10 #include <linux/tick.h>
 11 #include <linux/slab.h>
 12 
 13 #include "cpupri.h"
 14 #include "cpudeadline.h"
 15 #include "cpuacct.h"
 16 
 17 struct rq;
 18 struct cpuidle_state;
 19 
 20 /* task_struct::on_rq states: */
 21 #define TASK_ON_RQ_QUEUED       1
 22 #define TASK_ON_RQ_MIGRATING    2
 23 
 24 extern __read_mostly int scheduler_running;
 25 
 26 extern unsigned long calc_load_update;
 27 extern atomic_long_t calc_load_tasks;
 28 
 29 extern void calc_global_load_tick(struct rq *this_rq);
 30 extern long calc_load_fold_active(struct rq *this_rq);
 31 
 32 #ifdef CONFIG_SMP
 33 extern void update_cpu_load_active(struct rq *this_rq);
 34 #else
 35 static inline void update_cpu_load_active(struct rq *this_rq) { }
 36 #endif
 37 
 38 /*
 39  * Helpers for converting nanosecond timing to jiffy resolution
 40  */
 41 #define NS_TO_JIFFIES(TIME)     ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
 42 
 43 /*
 44  * Increase resolution of nice-level calculations for 64-bit architectures.
 45  * The extra resolution improves shares distribution and load balancing of
 46  * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
 47  * hierarchies, especially on larger systems. This is not a user-visible change
 48  * and does not change the user-interface for setting shares/weights.
 49  *
 50  * We increase resolution only if we have enough bits to allow this increased
 51  * resolution (i.e. BITS_PER_LONG > 32). The costs for increasing resolution
 52  * when BITS_PER_LONG <= 32 are pretty high and the returns do not justify the
 53  * increased costs.
 54  */
 55 #if 0 /* BITS_PER_LONG > 32 -- currently broken: it increases power usage under light load  */
 56 # define SCHED_LOAD_RESOLUTION  10
 57 # define scale_load(w)          ((w) << SCHED_LOAD_RESOLUTION)
 58 # define scale_load_down(w)     ((w) >> SCHED_LOAD_RESOLUTION)
 59 #else
 60 # define SCHED_LOAD_RESOLUTION  0
 61 # define scale_load(w)          (w)
 62 # define scale_load_down(w)     (w)
 63 #endif
 64 
 65 #define SCHED_LOAD_SHIFT        (10 + SCHED_LOAD_RESOLUTION)
 66 #define SCHED_LOAD_SCALE        (1L << SCHED_LOAD_SHIFT)
 67 
 68 #define NICE_0_LOAD             SCHED_LOAD_SCALE
 69 #define NICE_0_SHIFT            SCHED_LOAD_SHIFT
 70 
 71 /*
 72  * Single value that decides SCHED_DEADLINE internal math precision.
 73  * 10 -> just above 1us
 74  * 9  -> just above 0.5us
 75  */
 76 #define DL_SCALE (10)
 77 
 78 /*
 79  * These are the 'tuning knobs' of the scheduler:
 80  */
 81 
 82 /*
 83  * single value that denotes runtime == period, ie unlimited time.
 84  */
 85 #define RUNTIME_INF     ((u64)~0ULL)
 86 
 87 static inline int idle_policy(int policy)
 88 {
 89         return policy == SCHED_IDLE;
 90 }
 91 static inline int fair_policy(int policy)
 92 {
 93         return policy == SCHED_NORMAL || policy == SCHED_BATCH;
 94 }
 95 
 96 static inline int rt_policy(int policy)
 97 {
 98         return policy == SCHED_FIFO || policy == SCHED_RR;
 99 }
100 
101 static inline int dl_policy(int policy)
102 {
103         return policy == SCHED_DEADLINE;
104 }
105 static inline bool valid_policy(int policy)
106 {
107         return idle_policy(policy) || fair_policy(policy) ||
108                 rt_policy(policy) || dl_policy(policy);
109 }
110 
111 static inline int task_has_rt_policy(struct task_struct *p)
112 {
113         return rt_policy(p->policy);
114 }
115 
116 static inline int task_has_dl_policy(struct task_struct *p)
117 {
118         return dl_policy(p->policy);
119 }
120 
121 /*
122  * Tells if entity @a should preempt entity @b.
123  */
124 static inline bool
125 dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
126 {
127         return dl_time_before(a->deadline, b->deadline);
128 }
129 
130 /*
131  * This is the priority-queue data structure of the RT scheduling class:
132  */
133 struct rt_prio_array {
134         DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
135         struct list_head queue[MAX_RT_PRIO];
136 };
137 
138 struct rt_bandwidth {
139         /* nests inside the rq lock: */
140         raw_spinlock_t          rt_runtime_lock;
141         ktime_t                 rt_period;
142         u64                     rt_runtime;
143         struct hrtimer          rt_period_timer;
144         unsigned int            rt_period_active;
145 };
146 
147 void __dl_clear_params(struct task_struct *p);
148 
149 /*
150  * To keep the bandwidth of -deadline tasks and groups under control
151  * we need some place where:
152  *  - store the maximum -deadline bandwidth of the system (the group);
153  *  - cache the fraction of that bandwidth that is currently allocated.
154  *
155  * This is all done in the data structure below. It is similar to the
156  * one used for RT-throttling (rt_bandwidth), with the main difference
157  * that, since here we are only interested in admission control, we
158  * do not decrease any runtime while the group "executes", neither we
159  * need a timer to replenish it.
160  *
161  * With respect to SMP, the bandwidth is given on a per-CPU basis,
162  * meaning that:
163  *  - dl_bw (< 100%) is the bandwidth of the system (group) on each CPU;
164  *  - dl_total_bw array contains, in the i-eth element, the currently
165  *    allocated bandwidth on the i-eth CPU.
166  * Moreover, groups consume bandwidth on each CPU, while tasks only
167  * consume bandwidth on the CPU they're running on.
168  * Finally, dl_total_bw_cpu is used to cache the index of dl_total_bw
169  * that will be shown the next time the proc or cgroup controls will
170  * be red. It on its turn can be changed by writing on its own
171  * control.
172  */
173 struct dl_bandwidth {
174         raw_spinlock_t dl_runtime_lock;
175         u64 dl_runtime;
176         u64 dl_period;
177 };
178 
179 static inline int dl_bandwidth_enabled(void)
180 {
181         return sysctl_sched_rt_runtime >= 0;
182 }
183 
184 extern struct dl_bw *dl_bw_of(int i);
185 
186 struct dl_bw {
187         raw_spinlock_t lock;
188         u64 bw, total_bw;
189 };
190 
191 static inline
192 void __dl_clear(struct dl_bw *dl_b, u64 tsk_bw)
193 {
194         dl_b->total_bw -= tsk_bw;
195 }
196 
197 static inline
198 void __dl_add(struct dl_bw *dl_b, u64 tsk_bw)
199 {
200         dl_b->total_bw += tsk_bw;
201 }
202 
203 static inline
204 bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw)
205 {
206         return dl_b->bw != -1 &&
207                dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw;
208 }
209 
210 extern struct mutex sched_domains_mutex;
211 
212 #ifdef CONFIG_CGROUP_SCHED
213 
214 #include <linux/cgroup.h>
215 
216 struct cfs_rq;
217 struct rt_rq;
218 
219 extern struct list_head task_groups;
220 
221 struct cfs_bandwidth {
222 #ifdef CONFIG_CFS_BANDWIDTH
223         raw_spinlock_t lock;
224         ktime_t period;
225         u64 quota, runtime;
226         s64 hierarchical_quota;
227         u64 runtime_expires;
228 
229         int idle, period_active;
230         struct hrtimer period_timer, slack_timer;
231         struct list_head throttled_cfs_rq;
232 
233         /* statistics */
234         int nr_periods, nr_throttled;
235         u64 throttled_time;
236 #endif
237 };
238 
239 /* task group related information */
240 struct task_group {
241         struct cgroup_subsys_state css;
242 
243 #ifdef CONFIG_FAIR_GROUP_SCHED
244         /* schedulable entities of this group on each cpu */
245         struct sched_entity **se;
246         /* runqueue "owned" by this group on each cpu */
247         struct cfs_rq **cfs_rq;
248         unsigned long shares;
249 
250 #ifdef  CONFIG_SMP
251         /*
252          * load_avg can be heavily contended at clock tick time, so put
253          * it in its own cacheline separated from the fields above which
254          * will also be accessed at each tick.
255          */
256         atomic_long_t load_avg ____cacheline_aligned;
257 #endif
258 #endif
259 
260 #ifdef CONFIG_RT_GROUP_SCHED
261         struct sched_rt_entity **rt_se;
262         struct rt_rq **rt_rq;
263 
264         struct rt_bandwidth rt_bandwidth;
265 #endif
266 
267         struct rcu_head rcu;
268         struct list_head list;
269 
270         struct task_group *parent;
271         struct list_head siblings;
272         struct list_head children;
273 
274 #ifdef CONFIG_SCHED_AUTOGROUP
275         struct autogroup *autogroup;
276 #endif
277 
278         struct cfs_bandwidth cfs_bandwidth;
279 };
280 
281 #ifdef CONFIG_FAIR_GROUP_SCHED
282 #define ROOT_TASK_GROUP_LOAD    NICE_0_LOAD
283 
284 /*
285  * A weight of 0 or 1 can cause arithmetics problems.
286  * A weight of a cfs_rq is the sum of weights of which entities
287  * are queued on this cfs_rq, so a weight of a entity should not be
288  * too large, so as the shares value of a task group.
289  * (The default weight is 1024 - so there's no practical
290  *  limitation from this.)
291  */
292 #define MIN_SHARES      (1UL <<  1)
293 #define MAX_SHARES      (1UL << 18)
294 #endif
295 
296 typedef int (*tg_visitor)(struct task_group *, void *);
297 
298 extern int walk_tg_tree_from(struct task_group *from,
299                              tg_visitor down, tg_visitor up, void *data);
300 
301 /*
302  * Iterate the full tree, calling @down when first entering a node and @up when
303  * leaving it for the final time.
304  *
305  * Caller must hold rcu_lock or sufficient equivalent.
306  */
307 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
308 {
309         return walk_tg_tree_from(&root_task_group, down, up, data);
310 }
311 
312 extern int tg_nop(struct task_group *tg, void *data);
313 
314 extern void free_fair_sched_group(struct task_group *tg);
315 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
316 extern void unregister_fair_sched_group(struct task_group *tg, int cpu);
317 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
318                         struct sched_entity *se, int cpu,
319                         struct sched_entity *parent);
320 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
321 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
322 
323 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
324 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
325 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
326 
327 extern void free_rt_sched_group(struct task_group *tg);
328 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
329 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
330                 struct sched_rt_entity *rt_se, int cpu,
331                 struct sched_rt_entity *parent);
332 
333 extern struct task_group *sched_create_group(struct task_group *parent);
334 extern void sched_online_group(struct task_group *tg,
335                                struct task_group *parent);
336 extern void sched_destroy_group(struct task_group *tg);
337 extern void sched_offline_group(struct task_group *tg);
338 
339 extern void sched_move_task(struct task_struct *tsk);
340 
341 #ifdef CONFIG_FAIR_GROUP_SCHED
342 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
343 
344 #ifdef CONFIG_SMP
345 extern void set_task_rq_fair(struct sched_entity *se,
346                              struct cfs_rq *prev, struct cfs_rq *next);
347 #else /* !CONFIG_SMP */
348 static inline void set_task_rq_fair(struct sched_entity *se,
349                              struct cfs_rq *prev, struct cfs_rq *next) { }
350 #endif /* CONFIG_SMP */
351 #endif /* CONFIG_FAIR_GROUP_SCHED */
352 
353 #else /* CONFIG_CGROUP_SCHED */
354 
355 struct cfs_bandwidth { };
356 
357 #endif  /* CONFIG_CGROUP_SCHED */
358 
359 /* CFS-related fields in a runqueue */
360 struct cfs_rq {
361         struct load_weight load;
362         unsigned int nr_running, h_nr_running;
363 
364         u64 exec_clock;
365         u64 min_vruntime;
366 #ifndef CONFIG_64BIT
367         u64 min_vruntime_copy;
368 #endif
369 
370         struct rb_root tasks_timeline;
371         struct rb_node *rb_leftmost;
372 
373         /*
374          * 'curr' points to currently running entity on this cfs_rq.
375          * It is set to NULL otherwise (i.e when none are currently running).
376          */
377         struct sched_entity *curr, *next, *last, *skip;
378 
379 #ifdef  CONFIG_SCHED_DEBUG
380         unsigned int nr_spread_over;
381 #endif
382 
383 #ifdef CONFIG_SMP
384         /*
385          * CFS load tracking
386          */
387         struct sched_avg avg;
388         u64 runnable_load_sum;
389         unsigned long runnable_load_avg;
390 #ifdef CONFIG_FAIR_GROUP_SCHED
391         unsigned long tg_load_avg_contrib;
392 #endif
393         atomic_long_t removed_load_avg, removed_util_avg;
394 #ifndef CONFIG_64BIT
395         u64 load_last_update_time_copy;
396 #endif
397 
398 #ifdef CONFIG_FAIR_GROUP_SCHED
399         /*
400          *   h_load = weight * f(tg)
401          *
402          * Where f(tg) is the recursive weight fraction assigned to
403          * this group.
404          */
405         unsigned long h_load;
406         u64 last_h_load_update;
407         struct sched_entity *h_load_next;
408 #endif /* CONFIG_FAIR_GROUP_SCHED */
409 #endif /* CONFIG_SMP */
410 
411 #ifdef CONFIG_FAIR_GROUP_SCHED
412         struct rq *rq;  /* cpu runqueue to which this cfs_rq is attached */
413 
414         /*
415          * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
416          * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
417          * (like users, containers etc.)
418          *
419          * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This
420          * list is used during load balance.
421          */
422         int on_list;
423         struct list_head leaf_cfs_rq_list;
424         struct task_group *tg;  /* group that "owns" this runqueue */
425 
426 #ifdef CONFIG_CFS_BANDWIDTH
427         int runtime_enabled;
428         u64 runtime_expires;
429         s64 runtime_remaining;
430 
431         u64 throttled_clock, throttled_clock_task;
432         u64 throttled_clock_task_time;
433         int throttled, throttle_count;
434         struct list_head throttled_list;
435 #endif /* CONFIG_CFS_BANDWIDTH */
436 #endif /* CONFIG_FAIR_GROUP_SCHED */
437 };
438 
439 static inline int rt_bandwidth_enabled(void)
440 {
441         return sysctl_sched_rt_runtime >= 0;
442 }
443 
444 /* RT IPI pull logic requires IRQ_WORK */
445 #ifdef CONFIG_IRQ_WORK
446 # define HAVE_RT_PUSH_IPI
447 #endif
448 
449 /* Real-Time classes' related field in a runqueue: */
450 struct rt_rq {
451         struct rt_prio_array active;
452         unsigned int rt_nr_running;
453 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
454         struct {
455                 int curr; /* highest queued rt task prio */
456 #ifdef CONFIG_SMP
457                 int next; /* next highest */
458 #endif
459         } highest_prio;
460 #endif
461 #ifdef CONFIG_SMP
462         unsigned long rt_nr_migratory;
463         unsigned long rt_nr_total;
464         int overloaded;
465         struct plist_head pushable_tasks;
466 #ifdef HAVE_RT_PUSH_IPI
467         int push_flags;
468         int push_cpu;
469         struct irq_work push_work;
470         raw_spinlock_t push_lock;
471 #endif
472 #endif /* CONFIG_SMP */
473         int rt_queued;
474 
475         int rt_throttled;
476         u64 rt_time;
477         u64 rt_runtime;
478         /* Nests inside the rq lock: */
479         raw_spinlock_t rt_runtime_lock;
480 
481 #ifdef CONFIG_RT_GROUP_SCHED
482         unsigned long rt_nr_boosted;
483 
484         struct rq *rq;
485         struct task_group *tg;
486 #endif
487 };
488 
489 /* Deadline class' related fields in a runqueue */
490 struct dl_rq {
491         /* runqueue is an rbtree, ordered by deadline */
492         struct rb_root rb_root;
493         struct rb_node *rb_leftmost;
494 
495         unsigned long dl_nr_running;
496 
497 #ifdef CONFIG_SMP
498         /*
499          * Deadline values of the currently executing and the
500          * earliest ready task on this rq. Caching these facilitates
501          * the decision wether or not a ready but not running task
502          * should migrate somewhere else.
503          */
504         struct {
505                 u64 curr;
506                 u64 next;
507         } earliest_dl;
508 
509         unsigned long dl_nr_migratory;
510         int overloaded;
511 
512         /*
513          * Tasks on this rq that can be pushed away. They are kept in
514          * an rb-tree, ordered by tasks' deadlines, with caching
515          * of the leftmost (earliest deadline) element.
516          */
517         struct rb_root pushable_dl_tasks_root;
518         struct rb_node *pushable_dl_tasks_leftmost;
519 #else
520         struct dl_bw dl_bw;
521 #endif
522 };
523 
524 #ifdef CONFIG_SMP
525 
526 /*
527  * We add the notion of a root-domain which will be used to define per-domain
528  * variables. Each exclusive cpuset essentially defines an island domain by
529  * fully partitioning the member cpus from any other cpuset. Whenever a new
530  * exclusive cpuset is created, we also create and attach a new root-domain
531  * object.
532  *
533  */
534 struct root_domain {
535         atomic_t refcount;
536         atomic_t rto_count;
537         struct rcu_head rcu;
538         cpumask_var_t span;
539         cpumask_var_t online;
540 
541         /* Indicate more than one runnable task for any CPU */
542         bool overload;
543 
544         /*
545          * The bit corresponding to a CPU gets set here if such CPU has more
546          * than one runnable -deadline task (as it is below for RT tasks).
547          */
548         cpumask_var_t dlo_mask;
549         atomic_t dlo_count;
550         struct dl_bw dl_bw;
551         struct cpudl cpudl;
552 
553         /*
554          * The "RT overload" flag: it gets set if a CPU has more than
555          * one runnable RT task.
556          */
557         cpumask_var_t rto_mask;
558         struct cpupri cpupri;
559 };
560 
561 extern struct root_domain def_root_domain;
562 
563 #endif /* CONFIG_SMP */
564 
565 /*
566  * This is the main, per-CPU runqueue data structure.
567  *
568  * Locking rule: those places that want to lock multiple runqueues
569  * (such as the load balancing or the thread migration code), lock
570  * acquire operations must be ordered by ascending &runqueue.
571  */
572 struct rq {
573         /* runqueue lock: */
574         raw_spinlock_t lock;
575 
576         /*
577          * nr_running and cpu_load should be in the same cacheline because
578          * remote CPUs use both these fields when doing load calculation.
579          */
580         unsigned int nr_running;
581 #ifdef CONFIG_NUMA_BALANCING
582         unsigned int nr_numa_running;
583         unsigned int nr_preferred_running;
584 #endif
585         #define CPU_LOAD_IDX_MAX 5
586         unsigned long cpu_load[CPU_LOAD_IDX_MAX];
587         unsigned long last_load_update_tick;
588 #ifdef CONFIG_NO_HZ_COMMON
589         u64 nohz_stamp;
590         unsigned long nohz_flags;
591 #endif
592 #ifdef CONFIG_NO_HZ_FULL
593         unsigned long last_sched_tick;
594 #endif
595         /* capture load from *all* tasks on this cpu: */
596         struct load_weight load;
597         unsigned long nr_load_updates;
598         u64 nr_switches;
599 
600         struct cfs_rq cfs;
601         struct rt_rq rt;
602         struct dl_rq dl;
603 
604 #ifdef CONFIG_FAIR_GROUP_SCHED
605         /* list of leaf cfs_rq on this cpu: */
606         struct list_head leaf_cfs_rq_list;
607 #endif /* CONFIG_FAIR_GROUP_SCHED */
608 
609         /*
610          * This is part of a global counter where only the total sum
611          * over all CPUs matters. A task can increase this counter on
612          * one CPU and if it got migrated afterwards it may decrease
613          * it on another CPU. Always updated under the runqueue lock:
614          */
615         unsigned long nr_uninterruptible;
616 
617         struct task_struct *curr, *idle, *stop;
618         unsigned long next_balance;
619         struct mm_struct *prev_mm;
620 
621         unsigned int clock_skip_update;
622         u64 clock;
623         u64 clock_task;
624 
625         atomic_t nr_iowait;
626 
627 #ifdef CONFIG_SMP
628         struct root_domain *rd;
629         struct sched_domain *sd;
630 
631         unsigned long cpu_capacity;
632         unsigned long cpu_capacity_orig;
633 
634         struct callback_head *balance_callback;
635 
636         unsigned char idle_balance;
637         /* For active balancing */
638         int active_balance;
639         int push_cpu;
640         struct cpu_stop_work active_balance_work;
641         /* cpu of this runqueue: */
642         int cpu;
643         int online;
644 
645         struct list_head cfs_tasks;
646 
647         u64 rt_avg;
648         u64 age_stamp;
649         u64 idle_stamp;
650         u64 avg_idle;
651 
652         /* This is used to determine avg_idle's max value */
653         u64 max_idle_balance_cost;
654 #endif
655 
656 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
657         u64 prev_irq_time;
658 #endif
659 #ifdef CONFIG_PARAVIRT
660         u64 prev_steal_time;
661 #endif
662 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
663         u64 prev_steal_time_rq;
664 #endif
665 
666         /* calc_load related fields */
667         unsigned long calc_load_update;
668         long calc_load_active;
669 
670 #ifdef CONFIG_SCHED_HRTICK
671 #ifdef CONFIG_SMP
672         int hrtick_csd_pending;
673         struct call_single_data hrtick_csd;
674 #endif
675         struct hrtimer hrtick_timer;
676 #endif
677 
678 #ifdef CONFIG_SCHEDSTATS
679         /* latency stats */
680         struct sched_info rq_sched_info;
681         unsigned long long rq_cpu_time;
682         /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
683 
684         /* sys_sched_yield() stats */
685         unsigned int yld_count;
686 
687         /* schedule() stats */
688         unsigned int sched_count;
689         unsigned int sched_goidle;
690 
691         /* try_to_wake_up() stats */
692         unsigned int ttwu_count;
693         unsigned int ttwu_local;
694 #endif
695 
696 #ifdef CONFIG_SMP
697         struct llist_head wake_list;
698 #endif
699 
700 #ifdef CONFIG_CPU_IDLE
701         /* Must be inspected within a rcu lock section */
702         struct cpuidle_state *idle_state;
703 #endif
704 };
705 
706 static inline int cpu_of(struct rq *rq)
707 {
708 #ifdef CONFIG_SMP
709         return rq->cpu;
710 #else
711         return 0;
712 #endif
713 }
714 
715 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
716 
717 #define cpu_rq(cpu)             (&per_cpu(runqueues, (cpu)))
718 #define this_rq()               this_cpu_ptr(&runqueues)
719 #define task_rq(p)              cpu_rq(task_cpu(p))
720 #define cpu_curr(cpu)           (cpu_rq(cpu)->curr)
721 #define raw_rq()                raw_cpu_ptr(&runqueues)
722 
723 static inline u64 __rq_clock_broken(struct rq *rq)
724 {
725         return READ_ONCE(rq->clock);
726 }
727 
728 static inline u64 rq_clock(struct rq *rq)
729 {
730         lockdep_assert_held(&rq->lock);
731         return rq->clock;
732 }
733 
734 static inline u64 rq_clock_task(struct rq *rq)
735 {
736         lockdep_assert_held(&rq->lock);
737         return rq->clock_task;
738 }
739 
740 #define RQCF_REQ_SKIP   0x01
741 #define RQCF_ACT_SKIP   0x02
742 
743 static inline void rq_clock_skip_update(struct rq *rq, bool skip)
744 {
745         lockdep_assert_held(&rq->lock);
746         if (skip)
747                 rq->clock_skip_update |= RQCF_REQ_SKIP;
748         else
749                 rq->clock_skip_update &= ~RQCF_REQ_SKIP;
750 }
751 
752 #ifdef CONFIG_NUMA
753 enum numa_topology_type {
754         NUMA_DIRECT,
755         NUMA_GLUELESS_MESH,
756         NUMA_BACKPLANE,
757 };
758 extern enum numa_topology_type sched_numa_topology_type;
759 extern int sched_max_numa_distance;
760 extern bool find_numa_distance(int distance);
761 #endif
762 
763 #ifdef CONFIG_NUMA_BALANCING
764 /* The regions in numa_faults array from task_struct */
765 enum numa_faults_stats {
766         NUMA_MEM = 0,
767         NUMA_CPU,
768         NUMA_MEMBUF,
769         NUMA_CPUBUF
770 };
771 extern void sched_setnuma(struct task_struct *p, int node);
772 extern int migrate_task_to(struct task_struct *p, int cpu);
773 extern int migrate_swap(struct task_struct *, struct task_struct *);
774 #endif /* CONFIG_NUMA_BALANCING */
775 
776 #ifdef CONFIG_SMP
777 
778 static inline void
779 queue_balance_callback(struct rq *rq,
780                        struct callback_head *head,
781                        void (*func)(struct rq *rq))
782 {
783         lockdep_assert_held(&rq->lock);
784 
785         if (unlikely(head->next))
786                 return;
787 
788         head->func = (void (*)(struct callback_head *))func;
789         head->next = rq->balance_callback;
790         rq->balance_callback = head;
791 }
792 
793 extern void sched_ttwu_pending(void);
794 
795 #define rcu_dereference_check_sched_domain(p) \
796         rcu_dereference_check((p), \
797                               lockdep_is_held(&sched_domains_mutex))
798 
799 /*
800  * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
801  * See detach_destroy_domains: synchronize_sched for details.
802  *
803  * The domain tree of any CPU may only be accessed from within
804  * preempt-disabled sections.
805  */
806 #define for_each_domain(cpu, __sd) \
807         for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
808                         __sd; __sd = __sd->parent)
809 
810 #define for_each_lower_domain(sd) for (; sd; sd = sd->child)
811 
812 /**
813  * highest_flag_domain - Return highest sched_domain containing flag.
814  * @cpu:        The cpu whose highest level of sched domain is to
815  *              be returned.
816  * @flag:       The flag to check for the highest sched_domain
817  *              for the given cpu.
818  *
819  * Returns the highest sched_domain of a cpu which contains the given flag.
820  */
821 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
822 {
823         struct sched_domain *sd, *hsd = NULL;
824 
825         for_each_domain(cpu, sd) {
826                 if (!(sd->flags & flag))
827                         break;
828                 hsd = sd;
829         }
830 
831         return hsd;
832 }
833 
834 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
835 {
836         struct sched_domain *sd;
837 
838         for_each_domain(cpu, sd) {
839                 if (sd->flags & flag)
840                         break;
841         }
842 
843         return sd;
844 }
845 
846 DECLARE_PER_CPU(struct sched_domain *, sd_llc);
847 DECLARE_PER_CPU(int, sd_llc_size);
848 DECLARE_PER_CPU(int, sd_llc_id);
849 DECLARE_PER_CPU(struct sched_domain *, sd_numa);
850 DECLARE_PER_CPU(struct sched_domain *, sd_busy);
851 DECLARE_PER_CPU(struct sched_domain *, sd_asym);
852 
853 struct sched_group_capacity {
854         atomic_t ref;
855         /*
856          * CPU capacity of this group, SCHED_LOAD_SCALE being max capacity
857          * for a single CPU.
858          */
859         unsigned int capacity;
860         unsigned long next_update;
861         int imbalance; /* XXX unrelated to capacity but shared group state */
862         /*
863          * Number of busy cpus in this group.
864          */
865         atomic_t nr_busy_cpus;
866 
867         unsigned long cpumask[0]; /* iteration mask */
868 };
869 
870 struct sched_group {
871         struct sched_group *next;       /* Must be a circular list */
872         atomic_t ref;
873 
874         unsigned int group_weight;
875         struct sched_group_capacity *sgc;
876 
877         /*
878          * The CPUs this group covers.
879          *
880          * NOTE: this field is variable length. (Allocated dynamically
881          * by attaching extra space to the end of the structure,
882          * depending on how many CPUs the kernel has booted up with)
883          */
884         unsigned long cpumask[0];
885 };
886 
887 static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
888 {
889         return to_cpumask(sg->cpumask);
890 }
891 
892 /*
893  * cpumask masking which cpus in the group are allowed to iterate up the domain
894  * tree.
895  */
896 static inline struct cpumask *sched_group_mask(struct sched_group *sg)
897 {
898         return to_cpumask(sg->sgc->cpumask);
899 }
900 
901 /**
902  * group_first_cpu - Returns the first cpu in the cpumask of a sched_group.
903  * @group: The group whose first cpu is to be returned.
904  */
905 static inline unsigned int group_first_cpu(struct sched_group *group)
906 {
907         return cpumask_first(sched_group_cpus(group));
908 }
909 
910 extern int group_balance_cpu(struct sched_group *sg);
911 
912 #else
913 
914 static inline void sched_ttwu_pending(void) { }
915 
916 #endif /* CONFIG_SMP */
917 
918 #include "stats.h"
919 #include "auto_group.h"
920 
921 #ifdef CONFIG_CGROUP_SCHED
922 
923 /*
924  * Return the group to which this tasks belongs.
925  *
926  * We cannot use task_css() and friends because the cgroup subsystem
927  * changes that value before the cgroup_subsys::attach() method is called,
928  * therefore we cannot pin it and might observe the wrong value.
929  *
930  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
931  * core changes this before calling sched_move_task().
932  *
933  * Instead we use a 'copy' which is updated from sched_move_task() while
934  * holding both task_struct::pi_lock and rq::lock.
935  */
936 static inline struct task_group *task_group(struct task_struct *p)
937 {
938         return p->sched_task_group;
939 }
940 
941 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
942 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
943 {
944 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
945         struct task_group *tg = task_group(p);
946 #endif
947 
948 #ifdef CONFIG_FAIR_GROUP_SCHED
949         set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
950         p->se.cfs_rq = tg->cfs_rq[cpu];
951         p->se.parent = tg->se[cpu];
952 #endif
953 
954 #ifdef CONFIG_RT_GROUP_SCHED
955         p->rt.rt_rq  = tg->rt_rq[cpu];
956         p->rt.parent = tg->rt_se[cpu];
957 #endif
958 }
959 
960 #else /* CONFIG_CGROUP_SCHED */
961 
962 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
963 static inline struct task_group *task_group(struct task_struct *p)
964 {
965         return NULL;
966 }
967 
968 #endif /* CONFIG_CGROUP_SCHED */
969 
970 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
971 {
972         set_task_rq(p, cpu);
973 #ifdef CONFIG_SMP
974         /*
975          * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
976          * successfuly executed on another CPU. We must ensure that updates of
977          * per-task data have been completed by this moment.
978          */
979         smp_wmb();
980         task_thread_info(p)->cpu = cpu;
981         p->wake_cpu = cpu;
982 #endif
983 }
984 
985 /*
986  * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
987  */
988 #ifdef CONFIG_SCHED_DEBUG
989 # include <linux/static_key.h>
990 # define const_debug __read_mostly
991 #else
992 # define const_debug const
993 #endif
994 
995 extern const_debug unsigned int sysctl_sched_features;
996 
997 #define SCHED_FEAT(name, enabled)       \
998         __SCHED_FEAT_##name ,
999 
1000 enum {
1001 #include "features.h"
1002         __SCHED_FEAT_NR,
1003 };
1004 
1005 #undef SCHED_FEAT
1006 
1007 #if defined(CONFIG_SCHED_DEBUG) && defined(HAVE_JUMP_LABEL)
1008 #define SCHED_FEAT(name, enabled)                                       \
1009 static __always_inline bool static_branch_##name(struct static_key *key) \
1010 {                                                                       \
1011         return static_key_##enabled(key);                               \
1012 }
1013 
1014 #include "features.h"
1015 
1016 #undef SCHED_FEAT
1017 
1018 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
1019 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
1020 #else /* !(SCHED_DEBUG && HAVE_JUMP_LABEL) */
1021 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1022 #endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */
1023 
1024 extern struct static_key_false sched_numa_balancing;
1025 
1026 static inline u64 global_rt_period(void)
1027 {
1028         return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
1029 }
1030 
1031 static inline u64 global_rt_runtime(void)
1032 {
1033         if (sysctl_sched_rt_runtime < 0)
1034                 return RUNTIME_INF;
1035 
1036         return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
1037 }
1038 
1039 static inline int task_current(struct rq *rq, struct task_struct *p)
1040 {
1041         return rq->curr == p;
1042 }
1043 
1044 static inline int task_running(struct rq *rq, struct task_struct *p)
1045 {
1046 #ifdef CONFIG_SMP
1047         return p->on_cpu;
1048 #else
1049         return task_current(rq, p);
1050 #endif
1051 }
1052 
1053 static inline int task_on_rq_queued(struct task_struct *p)
1054 {
1055         return p->on_rq == TASK_ON_RQ_QUEUED;
1056 }
1057 
1058 static inline int task_on_rq_migrating(struct task_struct *p)
1059 {
1060         return p->on_rq == TASK_ON_RQ_MIGRATING;
1061 }
1062 
1063 #ifndef prepare_arch_switch
1064 # define prepare_arch_switch(next)      do { } while (0)
1065 #endif
1066 #ifndef finish_arch_post_lock_switch
1067 # define finish_arch_post_lock_switch() do { } while (0)
1068 #endif
1069 
1070 static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
1071 {
1072 #ifdef CONFIG_SMP
1073         /*
1074          * We can optimise this out completely for !SMP, because the
1075          * SMP rebalancing from interrupt is the only thing that cares
1076          * here.
1077          */
1078         next->on_cpu = 1;
1079 #endif
1080 }
1081 
1082 static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
1083 {
1084 #ifdef CONFIG_SMP
1085         /*
1086          * After ->on_cpu is cleared, the task can be moved to a different CPU.
1087          * We must ensure this doesn't happen until the switch is completely
1088          * finished.
1089          *
1090          * In particular, the load of prev->state in finish_task_switch() must
1091          * happen before this.
1092          *
1093          * Pairs with the smp_cond_acquire() in try_to_wake_up().
1094          */
1095         smp_store_release(&prev->on_cpu, 0);
1096 #endif
1097 #ifdef CONFIG_DEBUG_SPINLOCK
1098         /* this is a valid case when another task releases the spinlock */
1099         rq->lock.owner = current;
1100 #endif
1101         /*
1102          * If we are tracking spinlock dependencies then we have to
1103          * fix up the runqueue lock - which gets 'carried over' from
1104          * prev into current:
1105          */
1106         spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_);
1107 
1108         raw_spin_unlock_irq(&rq->lock);
1109 }
1110 
1111 /*
1112  * wake flags
1113  */
1114 #define WF_SYNC         0x01            /* waker goes to sleep after wakeup */
1115 #define WF_FORK         0x02            /* child wakeup after fork */
1116 #define WF_MIGRATED     0x4             /* internal use, task got migrated */
1117 
1118 /*
1119  * To aid in avoiding the subversion of "niceness" due to uneven distribution
1120  * of tasks with abnormal "nice" values across CPUs the contribution that
1121  * each task makes to its run queue's load is weighted according to its
1122  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
1123  * scaled version of the new time slice allocation that they receive on time
1124  * slice expiry etc.
1125  */
1126 
1127 #define WEIGHT_IDLEPRIO                3
1128 #define WMULT_IDLEPRIO         1431655765
1129 
1130 extern const int sched_prio_to_weight[40];
1131 extern const u32 sched_prio_to_wmult[40];
1132 
1133 #define ENQUEUE_WAKEUP          0x01
1134 #define ENQUEUE_HEAD            0x02
1135 #ifdef CONFIG_SMP
1136 #define ENQUEUE_WAKING          0x04    /* sched_class::task_waking was called */
1137 #else
1138 #define ENQUEUE_WAKING          0x00
1139 #endif
1140 #define ENQUEUE_REPLENISH       0x08
1141 #define ENQUEUE_RESTORE 0x10
1142 
1143 #define DEQUEUE_SLEEP           0x01
1144 #define DEQUEUE_SAVE            0x02
1145 
1146 #define RETRY_TASK              ((void *)-1UL)
1147 
1148 struct sched_class {
1149         const struct sched_class *next;
1150 
1151         void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1152         void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1153         void (*yield_task) (struct rq *rq);
1154         bool (*yield_to_task) (struct rq *rq, struct task_struct *p, bool preempt);
1155 
1156         void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
1157 
1158         /*
1159          * It is the responsibility of the pick_next_task() method that will
1160          * return the next task to call put_prev_task() on the @prev task or
1161          * something equivalent.
1162          *
1163          * May return RETRY_TASK when it finds a higher prio class has runnable
1164          * tasks.
1165          */
1166         struct task_struct * (*pick_next_task) (struct rq *rq,
1167                                                 struct task_struct *prev);
1168         void (*put_prev_task) (struct rq *rq, struct task_struct *p);
1169 
1170 #ifdef CONFIG_SMP
1171         int  (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
1172         void (*migrate_task_rq)(struct task_struct *p);
1173 
1174         void (*task_waking) (struct task_struct *task);
1175         void (*task_woken) (struct rq *this_rq, struct task_struct *task);
1176 
1177         void (*set_cpus_allowed)(struct task_struct *p,
1178                                  const struct cpumask *newmask);
1179 
1180         void (*rq_online)(struct rq *rq);
1181         void (*rq_offline)(struct rq *rq);
1182 #endif
1183 
1184         void (*set_curr_task) (struct rq *rq);
1185         void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1186         void (*task_fork) (struct task_struct *p);
1187         void (*task_dead) (struct task_struct *p);
1188 
1189         /*
1190          * The switched_from() call is allowed to drop rq->lock, therefore we
1191          * cannot assume the switched_from/switched_to pair is serliazed by
1192          * rq->lock. They are however serialized by p->pi_lock.
1193          */
1194         void (*switched_from) (struct rq *this_rq, struct task_struct *task);
1195         void (*switched_to) (struct rq *this_rq, struct task_struct *task);
1196         void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1197                              int oldprio);
1198 
1199         unsigned int (*get_rr_interval) (struct rq *rq,
1200                                          struct task_struct *task);
1201 
1202         void (*update_curr) (struct rq *rq);
1203 
1204 #ifdef CONFIG_FAIR_GROUP_SCHED
1205         void (*task_move_group) (struct task_struct *p);
1206 #endif
1207 };
1208 
1209 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
1210 {
1211         prev->sched_class->put_prev_task(rq, prev);
1212 }
1213 
1214 #define sched_class_highest (&stop_sched_class)
1215 #define for_each_class(class) \
1216    for (class = sched_class_highest; class; class = class->next)
1217 
1218 extern const struct sched_class stop_sched_class;
1219 extern const struct sched_class dl_sched_class;
1220 extern const struct sched_class rt_sched_class;
1221 extern const struct sched_class fair_sched_class;
1222 extern const struct sched_class idle_sched_class;
1223 
1224 
1225 #ifdef CONFIG_SMP
1226 
1227 extern void update_group_capacity(struct sched_domain *sd, int cpu);
1228 
1229 extern void trigger_load_balance(struct rq *rq);
1230 
1231 extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask);
1232 
1233 #endif
1234 
1235 #ifdef CONFIG_CPU_IDLE
1236 static inline void idle_set_state(struct rq *rq,
1237                                   struct cpuidle_state *idle_state)
1238 {
1239         rq->idle_state = idle_state;
1240 }
1241 
1242 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1243 {
1244         WARN_ON(!rcu_read_lock_held());
1245         return rq->idle_state;
1246 }
1247 #else
1248 static inline void idle_set_state(struct rq *rq,
1249                                   struct cpuidle_state *idle_state)
1250 {
1251 }
1252 
1253 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1254 {
1255         return NULL;
1256 }
1257 #endif
1258 
1259 extern void sysrq_sched_debug_show(void);
1260 extern void sched_init_granularity(void);
1261 extern void update_max_interval(void);
1262 
1263 extern void init_sched_dl_class(void);
1264 extern void init_sched_rt_class(void);
1265 extern void init_sched_fair_class(void);
1266 
1267 extern void resched_curr(struct rq *rq);
1268 extern void resched_cpu(int cpu);
1269 
1270 extern struct rt_bandwidth def_rt_bandwidth;
1271 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
1272 
1273 extern struct dl_bandwidth def_dl_bandwidth;
1274 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
1275 extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
1276 
1277 unsigned long to_ratio(u64 period, u64 runtime);
1278 
1279 extern void init_entity_runnable_average(struct sched_entity *se);
1280 
1281 static inline void add_nr_running(struct rq *rq, unsigned count)
1282 {
1283         unsigned prev_nr = rq->nr_running;
1284 
1285         rq->nr_running = prev_nr + count;
1286 
1287         if (prev_nr < 2 && rq->nr_running >= 2) {
1288 #ifdef CONFIG_SMP
1289                 if (!rq->rd->overload)
1290                         rq->rd->overload = true;
1291 #endif
1292 
1293 #ifdef CONFIG_NO_HZ_FULL
1294                 if (tick_nohz_full_cpu(rq->cpu)) {
1295                         /*
1296                          * Tick is needed if more than one task runs on a CPU.
1297                          * Send the target an IPI to kick it out of nohz mode.
1298                          *
1299                          * We assume that IPI implies full memory barrier and the
1300                          * new value of rq->nr_running is visible on reception
1301                          * from the target.
1302                          */
1303                         tick_nohz_full_kick_cpu(rq->cpu);
1304                 }
1305 #endif
1306         }
1307 }
1308 
1309 static inline void sub_nr_running(struct rq *rq, unsigned count)
1310 {
1311         rq->nr_running -= count;
1312 }
1313 
1314 static inline void rq_last_tick_reset(struct rq *rq)
1315 {
1316 #ifdef CONFIG_NO_HZ_FULL
1317         rq->last_sched_tick = jiffies;
1318 #endif
1319 }
1320 
1321 extern void update_rq_clock(struct rq *rq);
1322 
1323 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
1324 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
1325 
1326 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
1327 
1328 extern const_debug unsigned int sysctl_sched_time_avg;
1329 extern const_debug unsigned int sysctl_sched_nr_migrate;
1330 extern const_debug unsigned int sysctl_sched_migration_cost;
1331 
1332 static inline u64 sched_avg_period(void)
1333 {
1334         return (u64)sysctl_sched_time_avg * NSEC_PER_MSEC / 2;
1335 }
1336 
1337 #ifdef CONFIG_SCHED_HRTICK
1338 
1339 /*
1340  * Use hrtick when:
1341  *  - enabled by features
1342  *  - hrtimer is actually high res
1343  */
1344 static inline int hrtick_enabled(struct rq *rq)
1345 {
1346         if (!sched_feat(HRTICK))
1347                 return 0;
1348         if (!cpu_active(cpu_of(rq)))
1349                 return 0;
1350         return hrtimer_is_hres_active(&rq->hrtick_timer);
1351 }
1352 
1353 void hrtick_start(struct rq *rq, u64 delay);
1354 
1355 #else
1356 
1357 static inline int hrtick_enabled(struct rq *rq)
1358 {
1359         return 0;
1360 }
1361 
1362 #endif /* CONFIG_SCHED_HRTICK */
1363 
1364 #ifdef CONFIG_SMP
1365 extern void sched_avg_update(struct rq *rq);
1366 
1367 #ifndef arch_scale_freq_capacity
1368 static __always_inline
1369 unsigned long arch_scale_freq_capacity(struct sched_domain *sd, int cpu)
1370 {
1371         return SCHED_CAPACITY_SCALE;
1372 }
1373 #endif
1374 
1375 #ifndef arch_scale_cpu_capacity
1376 static __always_inline
1377 unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu)
1378 {
1379         if (sd && (sd->flags & SD_SHARE_CPUCAPACITY) && (sd->span_weight > 1))
1380                 return sd->smt_gain / sd->span_weight;
1381 
1382         return SCHED_CAPACITY_SCALE;
1383 }
1384 #endif
1385 
1386 static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
1387 {
1388         rq->rt_avg += rt_delta * arch_scale_freq_capacity(NULL, cpu_of(rq));
1389         sched_avg_update(rq);
1390 }
1391 #else
1392 static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { }
1393 static inline void sched_avg_update(struct rq *rq) { }
1394 #endif
1395 
1396 /*
1397  * __task_rq_lock - lock the rq @p resides on.
1398  */
1399 static inline struct rq *__task_rq_lock(struct task_struct *p)
1400         __acquires(rq->lock)
1401 {
1402         struct rq *rq;
1403 
1404         lockdep_assert_held(&p->pi_lock);
1405 
1406         for (;;) {
1407                 rq = task_rq(p);
1408                 raw_spin_lock(&rq->lock);
1409                 if (likely(rq == task_rq(p) && !task_on_rq_migrating(p))) {
1410                         lockdep_pin_lock(&rq->lock);
1411                         return rq;
1412                 }
1413                 raw_spin_unlock(&rq->lock);
1414 
1415                 while (unlikely(task_on_rq_migrating(p)))
1416                         cpu_relax();
1417         }
1418 }
1419 
1420 /*
1421  * task_rq_lock - lock p->pi_lock and lock the rq @p resides on.
1422  */
1423 static inline struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags)
1424         __acquires(p->pi_lock)
1425         __acquires(rq->lock)
1426 {
1427         struct rq *rq;
1428 
1429         for (;;) {
1430                 raw_spin_lock_irqsave(&p->pi_lock, *flags);
1431                 rq = task_rq(p);
1432                 raw_spin_lock(&rq->lock);
1433                 /*
1434                  *      move_queued_task()              task_rq_lock()
1435                  *
1436                  *      ACQUIRE (rq->lock)
1437                  *      [S] ->on_rq = MIGRATING         [L] rq = task_rq()
1438                  *      WMB (__set_task_cpu())          ACQUIRE (rq->lock);
1439                  *      [S] ->cpu = new_cpu             [L] task_rq()
1440                  *                                      [L] ->on_rq
1441                  *      RELEASE (rq->lock)
1442                  *
1443                  * If we observe the old cpu in task_rq_lock, the acquire of
1444                  * the old rq->lock will fully serialize against the stores.
1445                  *
1446                  * If we observe the new cpu in task_rq_lock, the acquire will
1447                  * pair with the WMB to ensure we must then also see migrating.
1448                  */
1449                 if (likely(rq == task_rq(p) && !task_on_rq_migrating(p))) {
1450                         lockdep_pin_lock(&rq->lock);
1451                         return rq;
1452                 }
1453                 raw_spin_unlock(&rq->lock);
1454                 raw_spin_unlock_irqrestore(&p->pi_lock, *flags);
1455 
1456                 while (unlikely(task_on_rq_migrating(p)))
1457                         cpu_relax();
1458         }
1459 }
1460 
1461 static inline void __task_rq_unlock(struct rq *rq)
1462         __releases(rq->lock)
1463 {
1464         lockdep_unpin_lock(&rq->lock);
1465         raw_spin_unlock(&rq->lock);
1466 }
1467 
1468 static inline void
1469 task_rq_unlock(struct rq *rq, struct task_struct *p, unsigned long *flags)
1470         __releases(rq->lock)
1471         __releases(p->pi_lock)
1472 {
1473         lockdep_unpin_lock(&rq->lock);
1474         raw_spin_unlock(&rq->lock);
1475         raw_spin_unlock_irqrestore(&p->pi_lock, *flags);
1476 }
1477 
1478 #ifdef CONFIG_SMP
1479 #ifdef CONFIG_PREEMPT
1480 
1481 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2);
1482 
1483 /*
1484  * fair double_lock_balance: Safely acquires both rq->locks in a fair
1485  * way at the expense of forcing extra atomic operations in all
1486  * invocations.  This assures that the double_lock is acquired using the
1487  * same underlying policy as the spinlock_t on this architecture, which
1488  * reduces latency compared to the unfair variant below.  However, it
1489  * also adds more overhead and therefore may reduce throughput.
1490  */
1491 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1492         __releases(this_rq->lock)
1493         __acquires(busiest->lock)
1494         __acquires(this_rq->lock)
1495 {
1496         raw_spin_unlock(&this_rq->lock);
1497         double_rq_lock(this_rq, busiest);
1498 
1499         return 1;
1500 }
1501 
1502 #else
1503 /*
1504  * Unfair double_lock_balance: Optimizes throughput at the expense of
1505  * latency by eliminating extra atomic operations when the locks are
1506  * already in proper order on entry.  This favors lower cpu-ids and will
1507  * grant the double lock to lower cpus over higher ids under contention,
1508  * regardless of entry order into the function.
1509  */
1510 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1511         __releases(this_rq->lock)
1512         __acquires(busiest->lock)
1513         __acquires(this_rq->lock)
1514 {
1515         int ret = 0;
1516 
1517         if (unlikely(!raw_spin_trylock(&busiest->lock))) {
1518                 if (busiest < this_rq) {
1519                         raw_spin_unlock(&this_rq->lock);
1520                         raw_spin_lock(&busiest->lock);
1521                         raw_spin_lock_nested(&this_rq->lock,
1522                                               SINGLE_DEPTH_NESTING);
1523                         ret = 1;
1524                 } else
1525                         raw_spin_lock_nested(&busiest->lock,
1526                                               SINGLE_DEPTH_NESTING);
1527         }
1528         return ret;
1529 }
1530 
1531 #endif /* CONFIG_PREEMPT */
1532 
1533 /*
1534  * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
1535  */
1536 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
1537 {
1538         if (unlikely(!irqs_disabled())) {
1539                 /* printk() doesn't work good under rq->lock */
1540                 raw_spin_unlock(&this_rq->lock);
1541                 BUG_ON(1);
1542         }
1543 
1544         return _double_lock_balance(this_rq, busiest);
1545 }
1546 
1547 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
1548         __releases(busiest->lock)
1549 {
1550         raw_spin_unlock(&busiest->lock);
1551         lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
1552 }
1553 
1554 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
1555 {
1556         if (l1 > l2)
1557                 swap(l1, l2);
1558 
1559         spin_lock(l1);
1560         spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1561 }
1562 
1563 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
1564 {
1565         if (l1 > l2)
1566                 swap(l1, l2);
1567 
1568         spin_lock_irq(l1);
1569         spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1570 }
1571 
1572 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
1573 {
1574         if (l1 > l2)
1575                 swap(l1, l2);
1576 
1577         raw_spin_lock(l1);
1578         raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1579 }
1580 
1581 /*
1582  * double_rq_lock - safely lock two runqueues
1583  *
1584  * Note this does not disable interrupts like task_rq_lock,
1585  * you need to do so manually before calling.
1586  */
1587 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
1588         __acquires(rq1->lock)
1589         __acquires(rq2->lock)
1590 {
1591         BUG_ON(!irqs_disabled());
1592         if (rq1 == rq2) {
1593                 raw_spin_lock(&rq1->lock);
1594                 __acquire(rq2->lock);   /* Fake it out ;) */
1595         } else {
1596                 if (rq1 < rq2) {
1597                         raw_spin_lock(&rq1->lock);
1598                         raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
1599                 } else {
1600                         raw_spin_lock(&rq2->lock);
1601                         raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
1602                 }
1603         }
1604 }
1605 
1606 /*
1607  * double_rq_unlock - safely unlock two runqueues
1608  *
1609  * Note this does not restore interrupts like task_rq_unlock,
1610  * you need to do so manually after calling.
1611  */
1612 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
1613         __releases(rq1->lock)
1614         __releases(rq2->lock)
1615 {
1616         raw_spin_unlock(&rq1->lock);
1617         if (rq1 != rq2)
1618                 raw_spin_unlock(&rq2->lock);
1619         else
1620                 __release(rq2->lock);
1621 }
1622 
1623 #else /* CONFIG_SMP */
1624 
1625 /*
1626  * double_rq_lock - safely lock two runqueues
1627  *
1628  * Note this does not disable interrupts like task_rq_lock,
1629  * you need to do so manually before calling.
1630  */
1631 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
1632         __acquires(rq1->lock)
1633         __acquires(rq2->lock)
1634 {
1635         BUG_ON(!irqs_disabled());
1636         BUG_ON(rq1 != rq2);
1637         raw_spin_lock(&rq1->lock);
1638         __acquire(rq2->lock);   /* Fake it out ;) */
1639 }
1640 
1641 /*
1642  * double_rq_unlock - safely unlock two runqueues
1643  *
1644  * Note this does not restore interrupts like task_rq_unlock,
1645  * you need to do so manually after calling.
1646  */
1647 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
1648         __releases(rq1->lock)
1649         __releases(rq2->lock)
1650 {
1651         BUG_ON(rq1 != rq2);
1652         raw_spin_unlock(&rq1->lock);
1653         __release(rq2->lock);
1654 }
1655 
1656 #endif
1657 
1658 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
1659 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
1660 
1661 #ifdef  CONFIG_SCHED_DEBUG
1662 extern void print_cfs_stats(struct seq_file *m, int cpu);
1663 extern void print_rt_stats(struct seq_file *m, int cpu);
1664 extern void print_dl_stats(struct seq_file *m, int cpu);
1665 extern void
1666 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
1667 
1668 #ifdef CONFIG_NUMA_BALANCING
1669 extern void
1670 show_numa_stats(struct task_struct *p, struct seq_file *m);
1671 extern void
1672 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
1673         unsigned long tpf, unsigned long gsf, unsigned long gpf);
1674 #endif /* CONFIG_NUMA_BALANCING */
1675 #endif /* CONFIG_SCHED_DEBUG */
1676 
1677 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
1678 extern void init_rt_rq(struct rt_rq *rt_rq);
1679 extern void init_dl_rq(struct dl_rq *dl_rq);
1680 
1681 extern void cfs_bandwidth_usage_inc(void);
1682 extern void cfs_bandwidth_usage_dec(void);
1683 
1684 #ifdef CONFIG_NO_HZ_COMMON
1685 enum rq_nohz_flag_bits {
1686         NOHZ_TICK_STOPPED,
1687         NOHZ_BALANCE_KICK,
1688 };
1689 
1690 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
1691 #endif
1692 
1693 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1694 
1695 DECLARE_PER_CPU(u64, cpu_hardirq_time);
1696 DECLARE_PER_CPU(u64, cpu_softirq_time);
1697 
1698 #ifndef CONFIG_64BIT
1699 DECLARE_PER_CPU(seqcount_t, irq_time_seq);
1700 
1701 static inline void irq_time_write_begin(void)
1702 {
1703         __this_cpu_inc(irq_time_seq.sequence);
1704         smp_wmb();
1705 }
1706 
1707 static inline void irq_time_write_end(void)
1708 {
1709         smp_wmb();
1710         __this_cpu_inc(irq_time_seq.sequence);
1711 }
1712 
1713 static inline u64 irq_time_read(int cpu)
1714 {
1715         u64 irq_time;
1716         unsigned seq;
1717 
1718         do {
1719                 seq = read_seqcount_begin(&per_cpu(irq_time_seq, cpu));
1720                 irq_time = per_cpu(cpu_softirq_time, cpu) +
1721                            per_cpu(cpu_hardirq_time, cpu);
1722         } while (read_seqcount_retry(&per_cpu(irq_time_seq, cpu), seq));
1723 
1724         return irq_time;
1725 }
1726 #else /* CONFIG_64BIT */
1727 static inline void irq_time_write_begin(void)
1728 {
1729 }
1730 
1731 static inline void irq_time_write_end(void)
1732 {
1733 }
1734 
1735 static inline u64 irq_time_read(int cpu)
1736 {
1737         return per_cpu(cpu_softirq_time, cpu) + per_cpu(cpu_hardirq_time, cpu);
1738 }
1739 #endif /* CONFIG_64BIT */
1740 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
1741 
1742 static inline void account_reset_rq(struct rq *rq)
1743 {
1744 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1745         rq->prev_irq_time = 0;
1746 #endif
1747 #ifdef CONFIG_PARAVIRT
1748         rq->prev_steal_time = 0;
1749 #endif
1750 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1751         rq->prev_steal_time_rq = 0;
1752 #endif
1753 }
1754 

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