1  /* SPDX-License-Identifier: GPL-2.0 */
2  /*
3   * Scheduler internal types and methods:
4   */
5  #include <linux/sched.h>
6  
7  #include <linux/sched/autogroup.h>
8  #include <linux/sched/clock.h>
9  #include <linux/sched/coredump.h>
10  #include <linux/sched/cpufreq.h>
11  #include <linux/sched/cputime.h>
12  #include <linux/sched/deadline.h>
13  #include <linux/sched/debug.h>
14  #include <linux/sched/hotplug.h>
15  #include <linux/sched/idle.h>
16  #include <linux/sched/init.h>
17  #include <linux/sched/isolation.h>
18  #include <linux/sched/jobctl.h>
19  #include <linux/sched/loadavg.h>
20  #include <linux/sched/mm.h>
21  #include <linux/sched/nohz.h>
22  #include <linux/sched/numa_balancing.h>
23  #include <linux/sched/prio.h>
24  #include <linux/sched/rt.h>
25  #include <linux/sched/signal.h>
26  #include <linux/sched/smt.h>
27  #include <linux/sched/stat.h>
28  #include <linux/sched/sysctl.h>
29  #include <linux/sched/task.h>
30  #include <linux/sched/task_stack.h>
31  #include <linux/sched/topology.h>
32  #include <linux/sched/user.h>
33  #include <linux/sched/wake_q.h>
34  #include <linux/sched/xacct.h>
35  
36  #include <uapi/linux/sched/types.h>
37  
38  #include <linux/binfmts.h>
39  #include <linux/bitops.h>
40  #include <linux/blkdev.h>
41  #include <linux/compat.h>
42  #include <linux/context_tracking.h>
43  #include <linux/cpufreq.h>
44  #include <linux/cpuidle.h>
45  #include <linux/cpuset.h>
46  #include <linux/ctype.h>
47  #include <linux/debugfs.h>
48  #include <linux/delayacct.h>
49  #include <linux/energy_model.h>
50  #include <linux/init_task.h>
51  #include <linux/kprobes.h>
52  #include <linux/kthread.h>
53  #include <linux/membarrier.h>
54  #include <linux/migrate.h>
55  #include <linux/mmu_context.h>
56  #include <linux/nmi.h>
57  #include <linux/proc_fs.h>
58  #include <linux/prefetch.h>
59  #include <linux/profile.h>
60  #include <linux/psi.h>
61  #include <linux/ratelimit.h>
62  #include <linux/rcupdate_wait.h>
63  #include <linux/security.h>
64  #include <linux/stop_machine.h>
65  #include <linux/suspend.h>
66  #include <linux/swait.h>
67  #include <linux/syscalls.h>
68  #include <linux/task_work.h>
69  #include <linux/tsacct_kern.h>
70  
71  #include <asm/tlb.h>
72  
73  #ifdef CONFIG_PARAVIRT
74  # include <asm/paravirt.h>
75  #endif
76  
77  #include "cpupri.h"
78  #include "cpudeadline.h"
79  
80  #include <trace/events/sched.h>
81  
82  #ifdef CONFIG_SCHED_DEBUG
83  # define SCHED_WARN_ON(x)	WARN_ONCE(x, #x)
84  #else
85  # define SCHED_WARN_ON(x)	({ (void)(x), 0; })
86  #endif
87  
88  struct rq;
89  struct cpuidle_state;
90  
91  /* task_struct::on_rq states: */
92  #define TASK_ON_RQ_QUEUED	1
93  #define TASK_ON_RQ_MIGRATING	2
94  
95  extern __read_mostly int scheduler_running;
96  
97  extern unsigned long calc_load_update;
98  extern atomic_long_t calc_load_tasks;
99  
100  extern void calc_global_load_tick(struct rq *this_rq);
101  extern long calc_load_fold_active(struct rq *this_rq, long adjust);
102  
103  extern void call_trace_sched_update_nr_running(struct rq *rq, int count);
104  /*
105   * Helpers for converting nanosecond timing to jiffy resolution
106   */
107  #define NS_TO_JIFFIES(TIME)	((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
108  
109  /*
110   * Increase resolution of nice-level calculations for 64-bit architectures.
111   * The extra resolution improves shares distribution and load balancing of
112   * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
113   * hierarchies, especially on larger systems. This is not a user-visible change
114   * and does not change the user-interface for setting shares/weights.
115   *
116   * We increase resolution only if we have enough bits to allow this increased
117   * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
118   * are pretty high and the returns do not justify the increased costs.
119   *
120   * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
121   * increase coverage and consistency always enable it on 64-bit platforms.
122   */
123  #ifdef CONFIG_64BIT
124  # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
125  # define scale_load(w)		((w) << SCHED_FIXEDPOINT_SHIFT)
126  # define scale_load_down(w) \
127  ({ \
128  	unsigned long __w = (w); \
129  	if (__w) \
130  		__w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \
131  	__w; \
132  })
133  #else
134  # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT)
135  # define scale_load(w)		(w)
136  # define scale_load_down(w)	(w)
137  #endif
138  
139  /*
140   * Task weight (visible to users) and its load (invisible to users) have
141   * independent resolution, but they should be well calibrated. We use
142   * scale_load() and scale_load_down(w) to convert between them. The
143   * following must be true:
144   *
145   *  scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD
146   *
147   */
148  #define NICE_0_LOAD		(1L << NICE_0_LOAD_SHIFT)
149  
150  /*
151   * Single value that decides SCHED_DEADLINE internal math precision.
152   * 10 -> just above 1us
153   * 9  -> just above 0.5us
154   */
155  #define DL_SCALE		10
156  
157  /*
158   * Single value that denotes runtime == period, ie unlimited time.
159   */
160  #define RUNTIME_INF		((u64)~0ULL)
161  
idle_policy(int policy)162  static inline int idle_policy(int policy)
163  {
164  	return policy == SCHED_IDLE;
165  }
fair_policy(int policy)166  static inline int fair_policy(int policy)
167  {
168  	return policy == SCHED_NORMAL || policy == SCHED_BATCH;
169  }
170  
rt_policy(int policy)171  static inline int rt_policy(int policy)
172  {
173  	return policy == SCHED_FIFO || policy == SCHED_RR;
174  }
175  
dl_policy(int policy)176  static inline int dl_policy(int policy)
177  {
178  	return policy == SCHED_DEADLINE;
179  }
valid_policy(int policy)180  static inline bool valid_policy(int policy)
181  {
182  	return idle_policy(policy) || fair_policy(policy) ||
183  		rt_policy(policy) || dl_policy(policy);
184  }
185  
task_has_idle_policy(struct task_struct * p)186  static inline int task_has_idle_policy(struct task_struct *p)
187  {
188  	return idle_policy(p->policy);
189  }
190  
task_has_rt_policy(struct task_struct * p)191  static inline int task_has_rt_policy(struct task_struct *p)
192  {
193  	return rt_policy(p->policy);
194  }
195  
task_has_dl_policy(struct task_struct * p)196  static inline int task_has_dl_policy(struct task_struct *p)
197  {
198  	return dl_policy(p->policy);
199  }
200  
201  #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
202  
update_avg(u64 * avg,u64 sample)203  static inline void update_avg(u64 *avg, u64 sample)
204  {
205  	s64 diff = sample - *avg;
206  	*avg += diff / 8;
207  }
208  
209  /*
210   * Shifting a value by an exponent greater *or equal* to the size of said value
211   * is UB; cap at size-1.
212   */
213  #define shr_bound(val, shift)							\
214  	(val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1))
215  
216  /*
217   * !! For sched_setattr_nocheck() (kernel) only !!
218   *
219   * This is actually gross. :(
220   *
221   * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
222   * tasks, but still be able to sleep. We need this on platforms that cannot
223   * atomically change clock frequency. Remove once fast switching will be
224   * available on such platforms.
225   *
226   * SUGOV stands for SchedUtil GOVernor.
227   */
228  #define SCHED_FLAG_SUGOV	0x10000000
229  
230  #define SCHED_DL_FLAGS (SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV)
231  
dl_entity_is_special(struct sched_dl_entity * dl_se)232  static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se)
233  {
234  #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
235  	return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
236  #else
237  	return false;
238  #endif
239  }
240  
241  /*
242   * Tells if entity @a should preempt entity @b.
243   */
244  static inline bool
dl_entity_preempt(struct sched_dl_entity * a,struct sched_dl_entity * b)245  dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
246  {
247  	return dl_entity_is_special(a) ||
248  	       dl_time_before(a->deadline, b->deadline);
249  }
250  
251  /*
252   * This is the priority-queue data structure of the RT scheduling class:
253   */
254  struct rt_prio_array {
255  	DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
256  	struct list_head queue[MAX_RT_PRIO];
257  };
258  
259  struct rt_bandwidth {
260  	/* nests inside the rq lock: */
261  	raw_spinlock_t		rt_runtime_lock;
262  	ktime_t			rt_period;
263  	u64			rt_runtime;
264  	struct hrtimer		rt_period_timer;
265  	unsigned int		rt_period_active;
266  };
267  
268  void __dl_clear_params(struct task_struct *p);
269  
270  struct dl_bandwidth {
271  	raw_spinlock_t		dl_runtime_lock;
272  	u64			dl_runtime;
273  	u64			dl_period;
274  };
275  
dl_bandwidth_enabled(void)276  static inline int dl_bandwidth_enabled(void)
277  {
278  	return sysctl_sched_rt_runtime >= 0;
279  }
280  
281  /*
282   * To keep the bandwidth of -deadline tasks under control
283   * we need some place where:
284   *  - store the maximum -deadline bandwidth of each cpu;
285   *  - cache the fraction of bandwidth that is currently allocated in
286   *    each root domain;
287   *
288   * This is all done in the data structure below. It is similar to the
289   * one used for RT-throttling (rt_bandwidth), with the main difference
290   * that, since here we are only interested in admission control, we
291   * do not decrease any runtime while the group "executes", neither we
292   * need a timer to replenish it.
293   *
294   * With respect to SMP, bandwidth is given on a per root domain basis,
295   * meaning that:
296   *  - bw (< 100%) is the deadline bandwidth of each CPU;
297   *  - total_bw is the currently allocated bandwidth in each root domain;
298   */
299  struct dl_bw {
300  	raw_spinlock_t		lock;
301  	u64			bw;
302  	u64			total_bw;
303  };
304  
305  static inline void __dl_update(struct dl_bw *dl_b, s64 bw);
306  
307  static inline
__dl_sub(struct dl_bw * dl_b,u64 tsk_bw,int cpus)308  void __dl_sub(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
309  {
310  	dl_b->total_bw -= tsk_bw;
311  	__dl_update(dl_b, (s32)tsk_bw / cpus);
312  }
313  
314  static inline
__dl_add(struct dl_bw * dl_b,u64 tsk_bw,int cpus)315  void __dl_add(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
316  {
317  	dl_b->total_bw += tsk_bw;
318  	__dl_update(dl_b, -((s32)tsk_bw / cpus));
319  }
320  
__dl_overflow(struct dl_bw * dl_b,unsigned long cap,u64 old_bw,u64 new_bw)321  static inline bool __dl_overflow(struct dl_bw *dl_b, unsigned long cap,
322  				 u64 old_bw, u64 new_bw)
323  {
324  	return dl_b->bw != -1 &&
325  	       cap_scale(dl_b->bw, cap) < dl_b->total_bw - old_bw + new_bw;
326  }
327  
328  /*
329   * Verify the fitness of task @p to run on @cpu taking into account the
330   * CPU original capacity and the runtime/deadline ratio of the task.
331   *
332   * The function will return true if the CPU original capacity of the
333   * @cpu scaled by SCHED_CAPACITY_SCALE >= runtime/deadline ratio of the
334   * task and false otherwise.
335   */
dl_task_fits_capacity(struct task_struct * p,int cpu)336  static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
337  {
338  	unsigned long cap = arch_scale_cpu_capacity(cpu);
339  
340  	return cap_scale(p->dl.dl_deadline, cap) >= p->dl.dl_runtime;
341  }
342  
343  extern void init_dl_bw(struct dl_bw *dl_b);
344  extern int  sched_dl_global_validate(void);
345  extern void sched_dl_do_global(void);
346  extern int  sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
347  extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
348  extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
349  extern bool __checkparam_dl(const struct sched_attr *attr);
350  extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
351  extern int  dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
352  extern int  dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
353  extern bool dl_cpu_busy(unsigned int cpu);
354  
355  #ifdef CONFIG_CGROUP_SCHED
356  
357  #include <linux/cgroup.h>
358  #include <linux/psi.h>
359  
360  struct cfs_rq;
361  struct rt_rq;
362  
363  extern struct list_head task_groups;
364  
365  struct cfs_bandwidth {
366  #ifdef CONFIG_CFS_BANDWIDTH
367  	raw_spinlock_t		lock;
368  	ktime_t			period;
369  	u64			quota;
370  	u64			runtime;
371  	u64			burst;
372  	s64			hierarchical_quota;
373  
374  	u8			idle;
375  	u8			period_active;
376  	u8			slack_started;
377  	struct hrtimer		period_timer;
378  	struct hrtimer		slack_timer;
379  	struct list_head	throttled_cfs_rq;
380  
381  	/* Statistics: */
382  	int			nr_periods;
383  	int			nr_throttled;
384  	u64			throttled_time;
385  #endif
386  };
387  
388  /* Task group related information */
389  struct task_group {
390  	struct cgroup_subsys_state css;
391  
392  #ifdef CONFIG_FAIR_GROUP_SCHED
393  	/* schedulable entities of this group on each CPU */
394  	struct sched_entity	**se;
395  	/* runqueue "owned" by this group on each CPU */
396  	struct cfs_rq		**cfs_rq;
397  	unsigned long		shares;
398  
399  	/* A positive value indicates that this is a SCHED_IDLE group. */
400  	int			idle;
401  
402  #ifdef	CONFIG_SMP
403  	/*
404  	 * load_avg can be heavily contended at clock tick time, so put
405  	 * it in its own cacheline separated from the fields above which
406  	 * will also be accessed at each tick.
407  	 */
408  	atomic_long_t		load_avg ____cacheline_aligned;
409  #endif
410  #endif
411  
412  #ifdef CONFIG_RT_GROUP_SCHED
413  	struct sched_rt_entity	**rt_se;
414  	struct rt_rq		**rt_rq;
415  
416  	struct rt_bandwidth	rt_bandwidth;
417  #endif
418  
419  	struct rcu_head		rcu;
420  	struct list_head	list;
421  
422  	struct task_group	*parent;
423  	struct list_head	siblings;
424  	struct list_head	children;
425  
426  #ifdef CONFIG_SCHED_AUTOGROUP
427  	struct autogroup	*autogroup;
428  #endif
429  
430  	struct cfs_bandwidth	cfs_bandwidth;
431  
432  #ifdef CONFIG_UCLAMP_TASK_GROUP
433  	/* The two decimal precision [%] value requested from user-space */
434  	unsigned int		uclamp_pct[UCLAMP_CNT];
435  	/* Clamp values requested for a task group */
436  	struct uclamp_se	uclamp_req[UCLAMP_CNT];
437  	/* Effective clamp values used for a task group */
438  	struct uclamp_se	uclamp[UCLAMP_CNT];
439  #endif
440  
441  };
442  
443  #ifdef CONFIG_FAIR_GROUP_SCHED
444  #define ROOT_TASK_GROUP_LOAD	NICE_0_LOAD
445  
446  /*
447   * A weight of 0 or 1 can cause arithmetics problems.
448   * A weight of a cfs_rq is the sum of weights of which entities
449   * are queued on this cfs_rq, so a weight of a entity should not be
450   * too large, so as the shares value of a task group.
451   * (The default weight is 1024 - so there's no practical
452   *  limitation from this.)
453   */
454  #define MIN_SHARES		(1UL <<  1)
455  #define MAX_SHARES		(1UL << 18)
456  #endif
457  
458  typedef int (*tg_visitor)(struct task_group *, void *);
459  
460  extern int walk_tg_tree_from(struct task_group *from,
461  			     tg_visitor down, tg_visitor up, void *data);
462  
463  /*
464   * Iterate the full tree, calling @down when first entering a node and @up when
465   * leaving it for the final time.
466   *
467   * Caller must hold rcu_lock or sufficient equivalent.
468   */
walk_tg_tree(tg_visitor down,tg_visitor up,void * data)469  static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
470  {
471  	return walk_tg_tree_from(&root_task_group, down, up, data);
472  }
473  
474  extern int tg_nop(struct task_group *tg, void *data);
475  
476  extern void free_fair_sched_group(struct task_group *tg);
477  extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
478  extern void online_fair_sched_group(struct task_group *tg);
479  extern void unregister_fair_sched_group(struct task_group *tg);
480  extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
481  			struct sched_entity *se, int cpu,
482  			struct sched_entity *parent);
483  extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
484  
485  extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
486  extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
487  extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
488  
489  extern void free_rt_sched_group(struct task_group *tg);
490  extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
491  extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
492  		struct sched_rt_entity *rt_se, int cpu,
493  		struct sched_rt_entity *parent);
494  extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
495  extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
496  extern long sched_group_rt_runtime(struct task_group *tg);
497  extern long sched_group_rt_period(struct task_group *tg);
498  extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
499  
500  extern struct task_group *sched_create_group(struct task_group *parent);
501  extern void sched_online_group(struct task_group *tg,
502  			       struct task_group *parent);
503  extern void sched_destroy_group(struct task_group *tg);
504  extern void sched_offline_group(struct task_group *tg);
505  
506  extern void sched_move_task(struct task_struct *tsk);
507  
508  #ifdef CONFIG_FAIR_GROUP_SCHED
509  extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
510  
511  extern int sched_group_set_idle(struct task_group *tg, long idle);
512  
513  #ifdef CONFIG_SMP
514  extern void set_task_rq_fair(struct sched_entity *se,
515  			     struct cfs_rq *prev, struct cfs_rq *next);
516  #else /* !CONFIG_SMP */
set_task_rq_fair(struct sched_entity * se,struct cfs_rq * prev,struct cfs_rq * next)517  static inline void set_task_rq_fair(struct sched_entity *se,
518  			     struct cfs_rq *prev, struct cfs_rq *next) { }
519  #endif /* CONFIG_SMP */
520  #endif /* CONFIG_FAIR_GROUP_SCHED */
521  
522  #else /* CONFIG_CGROUP_SCHED */
523  
524  struct cfs_bandwidth { };
525  
526  #endif	/* CONFIG_CGROUP_SCHED */
527  
528  /* CFS-related fields in a runqueue */
529  struct cfs_rq {
530  	struct load_weight	load;
531  	unsigned int		nr_running;
532  	unsigned int		h_nr_running;      /* SCHED_{NORMAL,BATCH,IDLE} */
533  	unsigned int		idle_h_nr_running; /* SCHED_IDLE */
534  
535  	u64			exec_clock;
536  	u64			min_vruntime;
537  #ifdef CONFIG_SCHED_CORE
538  	unsigned int		forceidle_seq;
539  	u64			min_vruntime_fi;
540  #endif
541  
542  #ifndef CONFIG_64BIT
543  	u64			min_vruntime_copy;
544  #endif
545  
546  	struct rb_root_cached	tasks_timeline;
547  
548  	/*
549  	 * 'curr' points to currently running entity on this cfs_rq.
550  	 * It is set to NULL otherwise (i.e when none are currently running).
551  	 */
552  	struct sched_entity	*curr;
553  	struct sched_entity	*next;
554  	struct sched_entity	*last;
555  	struct sched_entity	*skip;
556  
557  #ifdef	CONFIG_SCHED_DEBUG
558  	unsigned int		nr_spread_over;
559  #endif
560  
561  #ifdef CONFIG_SMP
562  	/*
563  	 * CFS load tracking
564  	 */
565  	struct sched_avg	avg;
566  #ifndef CONFIG_64BIT
567  	u64			load_last_update_time_copy;
568  #endif
569  	struct {
570  		raw_spinlock_t	lock ____cacheline_aligned;
571  		int		nr;
572  		unsigned long	load_avg;
573  		unsigned long	util_avg;
574  		unsigned long	runnable_avg;
575  	} removed;
576  
577  #ifdef CONFIG_FAIR_GROUP_SCHED
578  	unsigned long		tg_load_avg_contrib;
579  	long			propagate;
580  	long			prop_runnable_sum;
581  
582  	/*
583  	 *   h_load = weight * f(tg)
584  	 *
585  	 * Where f(tg) is the recursive weight fraction assigned to
586  	 * this group.
587  	 */
588  	unsigned long		h_load;
589  	u64			last_h_load_update;
590  	struct sched_entity	*h_load_next;
591  #endif /* CONFIG_FAIR_GROUP_SCHED */
592  #endif /* CONFIG_SMP */
593  
594  #ifdef CONFIG_FAIR_GROUP_SCHED
595  	struct rq		*rq;	/* CPU runqueue to which this cfs_rq is attached */
596  
597  	/*
598  	 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
599  	 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
600  	 * (like users, containers etc.)
601  	 *
602  	 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
603  	 * This list is used during load balance.
604  	 */
605  	int			on_list;
606  	struct list_head	leaf_cfs_rq_list;
607  	struct task_group	*tg;	/* group that "owns" this runqueue */
608  
609  	/* Locally cached copy of our task_group's idle value */
610  	int			idle;
611  
612  #ifdef CONFIG_CFS_BANDWIDTH
613  	int			runtime_enabled;
614  	s64			runtime_remaining;
615  
616  	u64			throttled_clock;
617  	u64			throttled_clock_task;
618  	u64			throttled_clock_task_time;
619  	int			throttled;
620  	int			throttle_count;
621  	struct list_head	throttled_list;
622  #endif /* CONFIG_CFS_BANDWIDTH */
623  #endif /* CONFIG_FAIR_GROUP_SCHED */
624  };
625  
rt_bandwidth_enabled(void)626  static inline int rt_bandwidth_enabled(void)
627  {
628  	return sysctl_sched_rt_runtime >= 0;
629  }
630  
631  /* RT IPI pull logic requires IRQ_WORK */
632  #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
633  # define HAVE_RT_PUSH_IPI
634  #endif
635  
636  /* Real-Time classes' related field in a runqueue: */
637  struct rt_rq {
638  	struct rt_prio_array	active;
639  	unsigned int		rt_nr_running;
640  	unsigned int		rr_nr_running;
641  #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
642  	struct {
643  		int		curr; /* highest queued rt task prio */
644  #ifdef CONFIG_SMP
645  		int		next; /* next highest */
646  #endif
647  	} highest_prio;
648  #endif
649  #ifdef CONFIG_SMP
650  	unsigned int		rt_nr_migratory;
651  	unsigned int		rt_nr_total;
652  	int			overloaded;
653  	struct plist_head	pushable_tasks;
654  
655  #endif /* CONFIG_SMP */
656  	int			rt_queued;
657  
658  	int			rt_throttled;
659  	u64			rt_time;
660  	u64			rt_runtime;
661  	/* Nests inside the rq lock: */
662  	raw_spinlock_t		rt_runtime_lock;
663  
664  #ifdef CONFIG_RT_GROUP_SCHED
665  	unsigned int		rt_nr_boosted;
666  
667  	struct rq		*rq;
668  	struct task_group	*tg;
669  #endif
670  };
671  
rt_rq_is_runnable(struct rt_rq * rt_rq)672  static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
673  {
674  	return rt_rq->rt_queued && rt_rq->rt_nr_running;
675  }
676  
677  /* Deadline class' related fields in a runqueue */
678  struct dl_rq {
679  	/* runqueue is an rbtree, ordered by deadline */
680  	struct rb_root_cached	root;
681  
682  	unsigned int		dl_nr_running;
683  
684  #ifdef CONFIG_SMP
685  	/*
686  	 * Deadline values of the currently executing and the
687  	 * earliest ready task on this rq. Caching these facilitates
688  	 * the decision whether or not a ready but not running task
689  	 * should migrate somewhere else.
690  	 */
691  	struct {
692  		u64		curr;
693  		u64		next;
694  	} earliest_dl;
695  
696  	unsigned int		dl_nr_migratory;
697  	int			overloaded;
698  
699  	/*
700  	 * Tasks on this rq that can be pushed away. They are kept in
701  	 * an rb-tree, ordered by tasks' deadlines, with caching
702  	 * of the leftmost (earliest deadline) element.
703  	 */
704  	struct rb_root_cached	pushable_dl_tasks_root;
705  #else
706  	struct dl_bw		dl_bw;
707  #endif
708  	/*
709  	 * "Active utilization" for this runqueue: increased when a
710  	 * task wakes up (becomes TASK_RUNNING) and decreased when a
711  	 * task blocks
712  	 */
713  	u64			running_bw;
714  
715  	/*
716  	 * Utilization of the tasks "assigned" to this runqueue (including
717  	 * the tasks that are in runqueue and the tasks that executed on this
718  	 * CPU and blocked). Increased when a task moves to this runqueue, and
719  	 * decreased when the task moves away (migrates, changes scheduling
720  	 * policy, or terminates).
721  	 * This is needed to compute the "inactive utilization" for the
722  	 * runqueue (inactive utilization = this_bw - running_bw).
723  	 */
724  	u64			this_bw;
725  	u64			extra_bw;
726  
727  	/*
728  	 * Inverse of the fraction of CPU utilization that can be reclaimed
729  	 * by the GRUB algorithm.
730  	 */
731  	u64			bw_ratio;
732  };
733  
734  #ifdef CONFIG_FAIR_GROUP_SCHED
735  /* An entity is a task if it doesn't "own" a runqueue */
736  #define entity_is_task(se)	(!se->my_q)
737  
se_update_runnable(struct sched_entity * se)738  static inline void se_update_runnable(struct sched_entity *se)
739  {
740  	if (!entity_is_task(se))
741  		se->runnable_weight = se->my_q->h_nr_running;
742  }
743  
se_runnable(struct sched_entity * se)744  static inline long se_runnable(struct sched_entity *se)
745  {
746  	if (entity_is_task(se))
747  		return !!se->on_rq;
748  	else
749  		return se->runnable_weight;
750  }
751  
752  #else
753  #define entity_is_task(se)	1
754  
se_update_runnable(struct sched_entity * se)755  static inline void se_update_runnable(struct sched_entity *se) {}
756  
se_runnable(struct sched_entity * se)757  static inline long se_runnable(struct sched_entity *se)
758  {
759  	return !!se->on_rq;
760  }
761  #endif
762  
763  #ifdef CONFIG_SMP
764  /*
765   * XXX we want to get rid of these helpers and use the full load resolution.
766   */
se_weight(struct sched_entity * se)767  static inline long se_weight(struct sched_entity *se)
768  {
769  	return scale_load_down(se->load.weight);
770  }
771  
772  
sched_asym_prefer(int a,int b)773  static inline bool sched_asym_prefer(int a, int b)
774  {
775  	return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
776  }
777  
778  struct perf_domain {
779  	struct em_perf_domain *em_pd;
780  	struct perf_domain *next;
781  	struct rcu_head rcu;
782  };
783  
784  /* Scheduling group status flags */
785  #define SG_OVERLOAD		0x1 /* More than one runnable task on a CPU. */
786  #define SG_OVERUTILIZED		0x2 /* One or more CPUs are over-utilized. */
787  
788  /*
789   * We add the notion of a root-domain which will be used to define per-domain
790   * variables. Each exclusive cpuset essentially defines an island domain by
791   * fully partitioning the member CPUs from any other cpuset. Whenever a new
792   * exclusive cpuset is created, we also create and attach a new root-domain
793   * object.
794   *
795   */
796  struct root_domain {
797  	atomic_t		refcount;
798  	atomic_t		rto_count;
799  	struct rcu_head		rcu;
800  	cpumask_var_t		span;
801  	cpumask_var_t		online;
802  
803  	/*
804  	 * Indicate pullable load on at least one CPU, e.g:
805  	 * - More than one runnable task
806  	 * - Running task is misfit
807  	 */
808  	int			overload;
809  
810  	/* Indicate one or more cpus over-utilized (tipping point) */
811  	int			overutilized;
812  
813  	/*
814  	 * The bit corresponding to a CPU gets set here if such CPU has more
815  	 * than one runnable -deadline task (as it is below for RT tasks).
816  	 */
817  	cpumask_var_t		dlo_mask;
818  	atomic_t		dlo_count;
819  	struct dl_bw		dl_bw;
820  	struct cpudl		cpudl;
821  
822  	/*
823  	 * Indicate whether a root_domain's dl_bw has been checked or
824  	 * updated. It's monotonously increasing value.
825  	 *
826  	 * Also, some corner cases, like 'wrap around' is dangerous, but given
827  	 * that u64 is 'big enough'. So that shouldn't be a concern.
828  	 */
829  	u64 visit_gen;
830  
831  #ifdef HAVE_RT_PUSH_IPI
832  	/*
833  	 * For IPI pull requests, loop across the rto_mask.
834  	 */
835  	struct irq_work		rto_push_work;
836  	raw_spinlock_t		rto_lock;
837  	/* These are only updated and read within rto_lock */
838  	int			rto_loop;
839  	int			rto_cpu;
840  	/* These atomics are updated outside of a lock */
841  	atomic_t		rto_loop_next;
842  	atomic_t		rto_loop_start;
843  #endif
844  	/*
845  	 * The "RT overload" flag: it gets set if a CPU has more than
846  	 * one runnable RT task.
847  	 */
848  	cpumask_var_t		rto_mask;
849  	struct cpupri		cpupri;
850  
851  	unsigned long		max_cpu_capacity;
852  
853  	/*
854  	 * NULL-terminated list of performance domains intersecting with the
855  	 * CPUs of the rd. Protected by RCU.
856  	 */
857  	struct perf_domain __rcu *pd;
858  };
859  
860  extern void init_defrootdomain(void);
861  extern int sched_init_domains(const struct cpumask *cpu_map);
862  extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
863  extern void sched_get_rd(struct root_domain *rd);
864  extern void sched_put_rd(struct root_domain *rd);
865  
866  #ifdef HAVE_RT_PUSH_IPI
867  extern void rto_push_irq_work_func(struct irq_work *work);
868  #endif
869  #endif /* CONFIG_SMP */
870  
871  #ifdef CONFIG_UCLAMP_TASK
872  /*
873   * struct uclamp_bucket - Utilization clamp bucket
874   * @value: utilization clamp value for tasks on this clamp bucket
875   * @tasks: number of RUNNABLE tasks on this clamp bucket
876   *
877   * Keep track of how many tasks are RUNNABLE for a given utilization
878   * clamp value.
879   */
880  struct uclamp_bucket {
881  	unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
882  	unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
883  };
884  
885  /*
886   * struct uclamp_rq - rq's utilization clamp
887   * @value: currently active clamp values for a rq
888   * @bucket: utilization clamp buckets affecting a rq
889   *
890   * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
891   * A clamp value is affecting a rq when there is at least one task RUNNABLE
892   * (or actually running) with that value.
893   *
894   * There are up to UCLAMP_CNT possible different clamp values, currently there
895   * are only two: minimum utilization and maximum utilization.
896   *
897   * All utilization clamping values are MAX aggregated, since:
898   * - for util_min: we want to run the CPU at least at the max of the minimum
899   *   utilization required by its currently RUNNABLE tasks.
900   * - for util_max: we want to allow the CPU to run up to the max of the
901   *   maximum utilization allowed by its currently RUNNABLE tasks.
902   *
903   * Since on each system we expect only a limited number of different
904   * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
905   * the metrics required to compute all the per-rq utilization clamp values.
906   */
907  struct uclamp_rq {
908  	unsigned int value;
909  	struct uclamp_bucket bucket[UCLAMP_BUCKETS];
910  };
911  
912  DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
913  #endif /* CONFIG_UCLAMP_TASK */
914  
915  /*
916   * This is the main, per-CPU runqueue data structure.
917   *
918   * Locking rule: those places that want to lock multiple runqueues
919   * (such as the load balancing or the thread migration code), lock
920   * acquire operations must be ordered by ascending &runqueue.
921   */
922  struct rq {
923  	/* runqueue lock: */
924  	raw_spinlock_t		__lock;
925  
926  	/*
927  	 * nr_running and cpu_load should be in the same cacheline because
928  	 * remote CPUs use both these fields when doing load calculation.
929  	 */
930  	unsigned int		nr_running;
931  #ifdef CONFIG_NUMA_BALANCING
932  	unsigned int		nr_numa_running;
933  	unsigned int		nr_preferred_running;
934  	unsigned int		numa_migrate_on;
935  #endif
936  #ifdef CONFIG_NO_HZ_COMMON
937  #ifdef CONFIG_SMP
938  	unsigned long		last_blocked_load_update_tick;
939  	unsigned int		has_blocked_load;
940  	call_single_data_t	nohz_csd;
941  #endif /* CONFIG_SMP */
942  	unsigned int		nohz_tick_stopped;
943  	atomic_t		nohz_flags;
944  #endif /* CONFIG_NO_HZ_COMMON */
945  
946  #ifdef CONFIG_SMP
947  	unsigned int		ttwu_pending;
948  #endif
949  	u64			nr_switches;
950  
951  #ifdef CONFIG_UCLAMP_TASK
952  	/* Utilization clamp values based on CPU's RUNNABLE tasks */
953  	struct uclamp_rq	uclamp[UCLAMP_CNT] ____cacheline_aligned;
954  	unsigned int		uclamp_flags;
955  #define UCLAMP_FLAG_IDLE 0x01
956  #endif
957  
958  	struct cfs_rq		cfs;
959  	struct rt_rq		rt;
960  	struct dl_rq		dl;
961  
962  #ifdef CONFIG_FAIR_GROUP_SCHED
963  	/* list of leaf cfs_rq on this CPU: */
964  	struct list_head	leaf_cfs_rq_list;
965  	struct list_head	*tmp_alone_branch;
966  #endif /* CONFIG_FAIR_GROUP_SCHED */
967  
968  	/*
969  	 * This is part of a global counter where only the total sum
970  	 * over all CPUs matters. A task can increase this counter on
971  	 * one CPU and if it got migrated afterwards it may decrease
972  	 * it on another CPU. Always updated under the runqueue lock:
973  	 */
974  	unsigned int		nr_uninterruptible;
975  
976  	struct task_struct __rcu	*curr;
977  	struct task_struct	*idle;
978  	struct task_struct	*stop;
979  	unsigned long		next_balance;
980  	struct mm_struct	*prev_mm;
981  
982  	unsigned int		clock_update_flags;
983  	u64			clock;
984  	/* Ensure that all clocks are in the same cache line */
985  	u64			clock_task ____cacheline_aligned;
986  	u64			clock_pelt;
987  	unsigned long		lost_idle_time;
988  
989  	atomic_t		nr_iowait;
990  
991  #ifdef CONFIG_SCHED_DEBUG
992  	u64 last_seen_need_resched_ns;
993  	int ticks_without_resched;
994  #endif
995  
996  #ifdef CONFIG_MEMBARRIER
997  	int membarrier_state;
998  #endif
999  
1000  #ifdef CONFIG_SMP
1001  	struct root_domain		*rd;
1002  	struct sched_domain __rcu	*sd;
1003  
1004  	unsigned long		cpu_capacity;
1005  	unsigned long		cpu_capacity_orig;
1006  
1007  	struct callback_head	*balance_callback;
1008  
1009  	unsigned char		nohz_idle_balance;
1010  	unsigned char		idle_balance;
1011  
1012  	unsigned long		misfit_task_load;
1013  
1014  	/* For active balancing */
1015  	int			active_balance;
1016  	int			push_cpu;
1017  	struct cpu_stop_work	active_balance_work;
1018  
1019  	/* CPU of this runqueue: */
1020  	int			cpu;
1021  	int			online;
1022  
1023  	struct list_head cfs_tasks;
1024  
1025  	struct sched_avg	avg_rt;
1026  	struct sched_avg	avg_dl;
1027  #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1028  	struct sched_avg	avg_irq;
1029  #endif
1030  #ifdef CONFIG_SCHED_THERMAL_PRESSURE
1031  	struct sched_avg	avg_thermal;
1032  #endif
1033  	u64			idle_stamp;
1034  	u64			avg_idle;
1035  
1036  	unsigned long		wake_stamp;
1037  	u64			wake_avg_idle;
1038  
1039  	/* This is used to determine avg_idle's max value */
1040  	u64			max_idle_balance_cost;
1041  
1042  #ifdef CONFIG_HOTPLUG_CPU
1043  	struct rcuwait		hotplug_wait;
1044  #endif
1045  #endif /* CONFIG_SMP */
1046  
1047  #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1048  	u64			prev_irq_time;
1049  #endif
1050  #ifdef CONFIG_PARAVIRT
1051  	u64			prev_steal_time;
1052  #endif
1053  #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1054  	u64			prev_steal_time_rq;
1055  #endif
1056  
1057  	/* calc_load related fields */
1058  	unsigned long		calc_load_update;
1059  	long			calc_load_active;
1060  
1061  #ifdef CONFIG_SCHED_HRTICK
1062  #ifdef CONFIG_SMP
1063  	call_single_data_t	hrtick_csd;
1064  #endif
1065  	struct hrtimer		hrtick_timer;
1066  	ktime_t 		hrtick_time;
1067  #endif
1068  
1069  #ifdef CONFIG_SCHEDSTATS
1070  	/* latency stats */
1071  	struct sched_info	rq_sched_info;
1072  	unsigned long long	rq_cpu_time;
1073  	/* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
1074  
1075  	/* sys_sched_yield() stats */
1076  	unsigned int		yld_count;
1077  
1078  	/* schedule() stats */
1079  	unsigned int		sched_count;
1080  	unsigned int		sched_goidle;
1081  
1082  	/* try_to_wake_up() stats */
1083  	unsigned int		ttwu_count;
1084  	unsigned int		ttwu_local;
1085  #endif
1086  
1087  #ifdef CONFIG_CPU_IDLE
1088  	/* Must be inspected within a rcu lock section */
1089  	struct cpuidle_state	*idle_state;
1090  #endif
1091  
1092  #ifdef CONFIG_SMP
1093  	unsigned int		nr_pinned;
1094  #endif
1095  	unsigned int		push_busy;
1096  	struct cpu_stop_work	push_work;
1097  
1098  #ifdef CONFIG_SCHED_CORE
1099  	/* per rq */
1100  	struct rq		*core;
1101  	struct task_struct	*core_pick;
1102  	unsigned int		core_enabled;
1103  	unsigned int		core_sched_seq;
1104  	struct rb_root		core_tree;
1105  
1106  	/* shared state -- careful with sched_core_cpu_deactivate() */
1107  	unsigned int		core_task_seq;
1108  	unsigned int		core_pick_seq;
1109  	unsigned long		core_cookie;
1110  	unsigned char		core_forceidle;
1111  	unsigned int		core_forceidle_seq;
1112  #endif
1113  };
1114  
1115  #ifdef CONFIG_FAIR_GROUP_SCHED
1116  
1117  /* CPU runqueue to which this cfs_rq is attached */
rq_of(struct cfs_rq * cfs_rq)1118  static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1119  {
1120  	return cfs_rq->rq;
1121  }
1122  
1123  #else
1124  
rq_of(struct cfs_rq * cfs_rq)1125  static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1126  {
1127  	return container_of(cfs_rq, struct rq, cfs);
1128  }
1129  #endif
1130  
cpu_of(struct rq * rq)1131  static inline int cpu_of(struct rq *rq)
1132  {
1133  #ifdef CONFIG_SMP
1134  	return rq->cpu;
1135  #else
1136  	return 0;
1137  #endif
1138  }
1139  
1140  #define MDF_PUSH	0x01
1141  
is_migration_disabled(struct task_struct * p)1142  static inline bool is_migration_disabled(struct task_struct *p)
1143  {
1144  #ifdef CONFIG_SMP
1145  	return p->migration_disabled;
1146  #else
1147  	return false;
1148  #endif
1149  }
1150  
1151  struct sched_group;
1152  #ifdef CONFIG_SCHED_CORE
1153  static inline struct cpumask *sched_group_span(struct sched_group *sg);
1154  
1155  DECLARE_STATIC_KEY_FALSE(__sched_core_enabled);
1156  
sched_core_enabled(struct rq * rq)1157  static inline bool sched_core_enabled(struct rq *rq)
1158  {
1159  	return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled;
1160  }
1161  
sched_core_disabled(void)1162  static inline bool sched_core_disabled(void)
1163  {
1164  	return !static_branch_unlikely(&__sched_core_enabled);
1165  }
1166  
1167  /*
1168   * Be careful with this function; not for general use. The return value isn't
1169   * stable unless you actually hold a relevant rq->__lock.
1170   */
rq_lockp(struct rq * rq)1171  static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1172  {
1173  	if (sched_core_enabled(rq))
1174  		return &rq->core->__lock;
1175  
1176  	return &rq->__lock;
1177  }
1178  
__rq_lockp(struct rq * rq)1179  static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1180  {
1181  	if (rq->core_enabled)
1182  		return &rq->core->__lock;
1183  
1184  	return &rq->__lock;
1185  }
1186  
1187  bool cfs_prio_less(struct task_struct *a, struct task_struct *b, bool fi);
1188  
1189  /*
1190   * Helpers to check if the CPU's core cookie matches with the task's cookie
1191   * when core scheduling is enabled.
1192   * A special case is that the task's cookie always matches with CPU's core
1193   * cookie if the CPU is in an idle core.
1194   */
sched_cpu_cookie_match(struct rq * rq,struct task_struct * p)1195  static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1196  {
1197  	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1198  	if (!sched_core_enabled(rq))
1199  		return true;
1200  
1201  	return rq->core->core_cookie == p->core_cookie;
1202  }
1203  
sched_core_cookie_match(struct rq * rq,struct task_struct * p)1204  static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1205  {
1206  	bool idle_core = true;
1207  	int cpu;
1208  
1209  	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1210  	if (!sched_core_enabled(rq))
1211  		return true;
1212  
1213  	for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) {
1214  		if (!available_idle_cpu(cpu)) {
1215  			idle_core = false;
1216  			break;
1217  		}
1218  	}
1219  
1220  	/*
1221  	 * A CPU in an idle core is always the best choice for tasks with
1222  	 * cookies.
1223  	 */
1224  	return idle_core || rq->core->core_cookie == p->core_cookie;
1225  }
1226  
sched_group_cookie_match(struct rq * rq,struct task_struct * p,struct sched_group * group)1227  static inline bool sched_group_cookie_match(struct rq *rq,
1228  					    struct task_struct *p,
1229  					    struct sched_group *group)
1230  {
1231  	int cpu;
1232  
1233  	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1234  	if (!sched_core_enabled(rq))
1235  		return true;
1236  
1237  	for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
1238  		if (sched_core_cookie_match(rq, p))
1239  			return true;
1240  	}
1241  	return false;
1242  }
1243  
1244  extern void queue_core_balance(struct rq *rq);
1245  
sched_core_enqueued(struct task_struct * p)1246  static inline bool sched_core_enqueued(struct task_struct *p)
1247  {
1248  	return !RB_EMPTY_NODE(&p->core_node);
1249  }
1250  
1251  extern void sched_core_enqueue(struct rq *rq, struct task_struct *p);
1252  extern void sched_core_dequeue(struct rq *rq, struct task_struct *p);
1253  
1254  extern void sched_core_get(void);
1255  extern void sched_core_put(void);
1256  
1257  extern unsigned long sched_core_alloc_cookie(void);
1258  extern void sched_core_put_cookie(unsigned long cookie);
1259  extern unsigned long sched_core_get_cookie(unsigned long cookie);
1260  extern unsigned long sched_core_update_cookie(struct task_struct *p, unsigned long cookie);
1261  
1262  #else /* !CONFIG_SCHED_CORE */
1263  
sched_core_enabled(struct rq * rq)1264  static inline bool sched_core_enabled(struct rq *rq)
1265  {
1266  	return false;
1267  }
1268  
sched_core_disabled(void)1269  static inline bool sched_core_disabled(void)
1270  {
1271  	return true;
1272  }
1273  
rq_lockp(struct rq * rq)1274  static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1275  {
1276  	return &rq->__lock;
1277  }
1278  
__rq_lockp(struct rq * rq)1279  static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1280  {
1281  	return &rq->__lock;
1282  }
1283  
queue_core_balance(struct rq * rq)1284  static inline void queue_core_balance(struct rq *rq)
1285  {
1286  }
1287  
sched_cpu_cookie_match(struct rq * rq,struct task_struct * p)1288  static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1289  {
1290  	return true;
1291  }
1292  
sched_core_cookie_match(struct rq * rq,struct task_struct * p)1293  static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1294  {
1295  	return true;
1296  }
1297  
sched_group_cookie_match(struct rq * rq,struct task_struct * p,struct sched_group * group)1298  static inline bool sched_group_cookie_match(struct rq *rq,
1299  					    struct task_struct *p,
1300  					    struct sched_group *group)
1301  {
1302  	return true;
1303  }
1304  #endif /* CONFIG_SCHED_CORE */
1305  
lockdep_assert_rq_held(struct rq * rq)1306  static inline void lockdep_assert_rq_held(struct rq *rq)
1307  {
1308  	lockdep_assert_held(__rq_lockp(rq));
1309  }
1310  
1311  extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass);
1312  extern bool raw_spin_rq_trylock(struct rq *rq);
1313  extern void raw_spin_rq_unlock(struct rq *rq);
1314  
raw_spin_rq_lock(struct rq * rq)1315  static inline void raw_spin_rq_lock(struct rq *rq)
1316  {
1317  	raw_spin_rq_lock_nested(rq, 0);
1318  }
1319  
raw_spin_rq_lock_irq(struct rq * rq)1320  static inline void raw_spin_rq_lock_irq(struct rq *rq)
1321  {
1322  	local_irq_disable();
1323  	raw_spin_rq_lock(rq);
1324  }
1325  
raw_spin_rq_unlock_irq(struct rq * rq)1326  static inline void raw_spin_rq_unlock_irq(struct rq *rq)
1327  {
1328  	raw_spin_rq_unlock(rq);
1329  	local_irq_enable();
1330  }
1331  
_raw_spin_rq_lock_irqsave(struct rq * rq)1332  static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq)
1333  {
1334  	unsigned long flags;
1335  	local_irq_save(flags);
1336  	raw_spin_rq_lock(rq);
1337  	return flags;
1338  }
1339  
raw_spin_rq_unlock_irqrestore(struct rq * rq,unsigned long flags)1340  static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags)
1341  {
1342  	raw_spin_rq_unlock(rq);
1343  	local_irq_restore(flags);
1344  }
1345  
1346  #define raw_spin_rq_lock_irqsave(rq, flags)	\
1347  do {						\
1348  	flags = _raw_spin_rq_lock_irqsave(rq);	\
1349  } while (0)
1350  
1351  #ifdef CONFIG_SCHED_SMT
1352  extern void __update_idle_core(struct rq *rq);
1353  
update_idle_core(struct rq * rq)1354  static inline void update_idle_core(struct rq *rq)
1355  {
1356  	if (static_branch_unlikely(&sched_smt_present))
1357  		__update_idle_core(rq);
1358  }
1359  
1360  #else
update_idle_core(struct rq * rq)1361  static inline void update_idle_core(struct rq *rq) { }
1362  #endif
1363  
1364  DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1365  
1366  #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
1367  #define this_rq()		this_cpu_ptr(&runqueues)
1368  #define task_rq(p)		cpu_rq(task_cpu(p))
1369  #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
1370  #define raw_rq()		raw_cpu_ptr(&runqueues)
1371  
1372  #ifdef CONFIG_FAIR_GROUP_SCHED
task_of(struct sched_entity * se)1373  static inline struct task_struct *task_of(struct sched_entity *se)
1374  {
1375  	SCHED_WARN_ON(!entity_is_task(se));
1376  	return container_of(se, struct task_struct, se);
1377  }
1378  
task_cfs_rq(struct task_struct * p)1379  static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1380  {
1381  	return p->se.cfs_rq;
1382  }
1383  
1384  /* runqueue on which this entity is (to be) queued */
cfs_rq_of(struct sched_entity * se)1385  static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se)
1386  {
1387  	return se->cfs_rq;
1388  }
1389  
1390  /* runqueue "owned" by this group */
group_cfs_rq(struct sched_entity * grp)1391  static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1392  {
1393  	return grp->my_q;
1394  }
1395  
1396  #else
1397  
task_of(struct sched_entity * se)1398  static inline struct task_struct *task_of(struct sched_entity *se)
1399  {
1400  	return container_of(se, struct task_struct, se);
1401  }
1402  
task_cfs_rq(struct task_struct * p)1403  static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1404  {
1405  	return &task_rq(p)->cfs;
1406  }
1407  
cfs_rq_of(struct sched_entity * se)1408  static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se)
1409  {
1410  	struct task_struct *p = task_of(se);
1411  	struct rq *rq = task_rq(p);
1412  
1413  	return &rq->cfs;
1414  }
1415  
1416  /* runqueue "owned" by this group */
group_cfs_rq(struct sched_entity * grp)1417  static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1418  {
1419  	return NULL;
1420  }
1421  #endif
1422  
1423  extern void update_rq_clock(struct rq *rq);
1424  
__rq_clock_broken(struct rq * rq)1425  static inline u64 __rq_clock_broken(struct rq *rq)
1426  {
1427  	return READ_ONCE(rq->clock);
1428  }
1429  
1430  /*
1431   * rq::clock_update_flags bits
1432   *
1433   * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1434   *  call to __schedule(). This is an optimisation to avoid
1435   *  neighbouring rq clock updates.
1436   *
1437   * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1438   *  in effect and calls to update_rq_clock() are being ignored.
1439   *
1440   * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1441   *  made to update_rq_clock() since the last time rq::lock was pinned.
1442   *
1443   * If inside of __schedule(), clock_update_flags will have been
1444   * shifted left (a left shift is a cheap operation for the fast path
1445   * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1446   *
1447   *	if (rq-clock_update_flags >= RQCF_UPDATED)
1448   *
1449   * to check if %RQCF_UPDATED is set. It'll never be shifted more than
1450   * one position though, because the next rq_unpin_lock() will shift it
1451   * back.
1452   */
1453  #define RQCF_REQ_SKIP		0x01
1454  #define RQCF_ACT_SKIP		0x02
1455  #define RQCF_UPDATED		0x04
1456  
assert_clock_updated(struct rq * rq)1457  static inline void assert_clock_updated(struct rq *rq)
1458  {
1459  	/*
1460  	 * The only reason for not seeing a clock update since the
1461  	 * last rq_pin_lock() is if we're currently skipping updates.
1462  	 */
1463  	SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
1464  }
1465  
rq_clock(struct rq * rq)1466  static inline u64 rq_clock(struct rq *rq)
1467  {
1468  	lockdep_assert_rq_held(rq);
1469  	assert_clock_updated(rq);
1470  
1471  	return rq->clock;
1472  }
1473  
rq_clock_task(struct rq * rq)1474  static inline u64 rq_clock_task(struct rq *rq)
1475  {
1476  	lockdep_assert_rq_held(rq);
1477  	assert_clock_updated(rq);
1478  
1479  	return rq->clock_task;
1480  }
1481  
1482  /**
1483   * By default the decay is the default pelt decay period.
1484   * The decay shift can change the decay period in
1485   * multiples of 32.
1486   *  Decay shift		Decay period(ms)
1487   *	0			32
1488   *	1			64
1489   *	2			128
1490   *	3			256
1491   *	4			512
1492   */
1493  extern int sched_thermal_decay_shift;
1494  
rq_clock_thermal(struct rq * rq)1495  static inline u64 rq_clock_thermal(struct rq *rq)
1496  {
1497  	return rq_clock_task(rq) >> sched_thermal_decay_shift;
1498  }
1499  
rq_clock_skip_update(struct rq * rq)1500  static inline void rq_clock_skip_update(struct rq *rq)
1501  {
1502  	lockdep_assert_rq_held(rq);
1503  	rq->clock_update_flags |= RQCF_REQ_SKIP;
1504  }
1505  
1506  /*
1507   * See rt task throttling, which is the only time a skip
1508   * request is canceled.
1509   */
rq_clock_cancel_skipupdate(struct rq * rq)1510  static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1511  {
1512  	lockdep_assert_rq_held(rq);
1513  	rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1514  }
1515  
1516  struct rq_flags {
1517  	unsigned long flags;
1518  	struct pin_cookie cookie;
1519  #ifdef CONFIG_SCHED_DEBUG
1520  	/*
1521  	 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1522  	 * current pin context is stashed here in case it needs to be
1523  	 * restored in rq_repin_lock().
1524  	 */
1525  	unsigned int clock_update_flags;
1526  #endif
1527  };
1528  
1529  extern struct callback_head balance_push_callback;
1530  
1531  /*
1532   * Lockdep annotation that avoids accidental unlocks; it's like a
1533   * sticky/continuous lockdep_assert_held().
1534   *
1535   * This avoids code that has access to 'struct rq *rq' (basically everything in
1536   * the scheduler) from accidentally unlocking the rq if they do not also have a
1537   * copy of the (on-stack) 'struct rq_flags rf'.
1538   *
1539   * Also see Documentation/locking/lockdep-design.rst.
1540   */
rq_pin_lock(struct rq * rq,struct rq_flags * rf)1541  static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1542  {
1543  	rf->cookie = lockdep_pin_lock(__rq_lockp(rq));
1544  
1545  #ifdef CONFIG_SCHED_DEBUG
1546  	rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1547  	rf->clock_update_flags = 0;
1548  #ifdef CONFIG_SMP
1549  	SCHED_WARN_ON(rq->balance_callback && rq->balance_callback != &balance_push_callback);
1550  #endif
1551  #endif
1552  }
1553  
rq_unpin_lock(struct rq * rq,struct rq_flags * rf)1554  static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1555  {
1556  #ifdef CONFIG_SCHED_DEBUG
1557  	if (rq->clock_update_flags > RQCF_ACT_SKIP)
1558  		rf->clock_update_flags = RQCF_UPDATED;
1559  #endif
1560  
1561  	lockdep_unpin_lock(__rq_lockp(rq), rf->cookie);
1562  }
1563  
rq_repin_lock(struct rq * rq,struct rq_flags * rf)1564  static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1565  {
1566  	lockdep_repin_lock(__rq_lockp(rq), rf->cookie);
1567  
1568  #ifdef CONFIG_SCHED_DEBUG
1569  	/*
1570  	 * Restore the value we stashed in @rf for this pin context.
1571  	 */
1572  	rq->clock_update_flags |= rf->clock_update_flags;
1573  #endif
1574  }
1575  
1576  struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1577  	__acquires(rq->lock);
1578  
1579  struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1580  	__acquires(p->pi_lock)
1581  	__acquires(rq->lock);
1582  
__task_rq_unlock(struct rq * rq,struct rq_flags * rf)1583  static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1584  	__releases(rq->lock)
1585  {
1586  	rq_unpin_lock(rq, rf);
1587  	raw_spin_rq_unlock(rq);
1588  }
1589  
1590  static inline void
task_rq_unlock(struct rq * rq,struct task_struct * p,struct rq_flags * rf)1591  task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1592  	__releases(rq->lock)
1593  	__releases(p->pi_lock)
1594  {
1595  	rq_unpin_lock(rq, rf);
1596  	raw_spin_rq_unlock(rq);
1597  	raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1598  }
1599  
1600  static inline void
rq_lock_irqsave(struct rq * rq,struct rq_flags * rf)1601  rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1602  	__acquires(rq->lock)
1603  {
1604  	raw_spin_rq_lock_irqsave(rq, rf->flags);
1605  	rq_pin_lock(rq, rf);
1606  }
1607  
1608  static inline void
rq_lock_irq(struct rq * rq,struct rq_flags * rf)1609  rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1610  	__acquires(rq->lock)
1611  {
1612  	raw_spin_rq_lock_irq(rq);
1613  	rq_pin_lock(rq, rf);
1614  }
1615  
1616  static inline void
rq_lock(struct rq * rq,struct rq_flags * rf)1617  rq_lock(struct rq *rq, struct rq_flags *rf)
1618  	__acquires(rq->lock)
1619  {
1620  	raw_spin_rq_lock(rq);
1621  	rq_pin_lock(rq, rf);
1622  }
1623  
1624  static inline void
rq_relock(struct rq * rq,struct rq_flags * rf)1625  rq_relock(struct rq *rq, struct rq_flags *rf)
1626  	__acquires(rq->lock)
1627  {
1628  	raw_spin_rq_lock(rq);
1629  	rq_repin_lock(rq, rf);
1630  }
1631  
1632  static inline void
rq_unlock_irqrestore(struct rq * rq,struct rq_flags * rf)1633  rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1634  	__releases(rq->lock)
1635  {
1636  	rq_unpin_lock(rq, rf);
1637  	raw_spin_rq_unlock_irqrestore(rq, rf->flags);
1638  }
1639  
1640  static inline void
rq_unlock_irq(struct rq * rq,struct rq_flags * rf)1641  rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1642  	__releases(rq->lock)
1643  {
1644  	rq_unpin_lock(rq, rf);
1645  	raw_spin_rq_unlock_irq(rq);
1646  }
1647  
1648  static inline void
rq_unlock(struct rq * rq,struct rq_flags * rf)1649  rq_unlock(struct rq *rq, struct rq_flags *rf)
1650  	__releases(rq->lock)
1651  {
1652  	rq_unpin_lock(rq, rf);
1653  	raw_spin_rq_unlock(rq);
1654  }
1655  
1656  static inline struct rq *
this_rq_lock_irq(struct rq_flags * rf)1657  this_rq_lock_irq(struct rq_flags *rf)
1658  	__acquires(rq->lock)
1659  {
1660  	struct rq *rq;
1661  
1662  	local_irq_disable();
1663  	rq = this_rq();
1664  	rq_lock(rq, rf);
1665  	return rq;
1666  }
1667  
1668  #ifdef CONFIG_NUMA
1669  enum numa_topology_type {
1670  	NUMA_DIRECT,
1671  	NUMA_GLUELESS_MESH,
1672  	NUMA_BACKPLANE,
1673  };
1674  extern enum numa_topology_type sched_numa_topology_type;
1675  extern int sched_max_numa_distance;
1676  extern bool find_numa_distance(int distance);
1677  extern void sched_init_numa(void);
1678  extern void sched_domains_numa_masks_set(unsigned int cpu);
1679  extern void sched_domains_numa_masks_clear(unsigned int cpu);
1680  extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1681  #else
sched_init_numa(void)1682  static inline void sched_init_numa(void) { }
sched_domains_numa_masks_set(unsigned int cpu)1683  static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
sched_domains_numa_masks_clear(unsigned int cpu)1684  static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
sched_numa_find_closest(const struct cpumask * cpus,int cpu)1685  static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1686  {
1687  	return nr_cpu_ids;
1688  }
1689  #endif
1690  
1691  #ifdef CONFIG_NUMA_BALANCING
1692  /* The regions in numa_faults array from task_struct */
1693  enum numa_faults_stats {
1694  	NUMA_MEM = 0,
1695  	NUMA_CPU,
1696  	NUMA_MEMBUF,
1697  	NUMA_CPUBUF
1698  };
1699  extern void sched_setnuma(struct task_struct *p, int node);
1700  extern int migrate_task_to(struct task_struct *p, int cpu);
1701  extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1702  			int cpu, int scpu);
1703  extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1704  #else
1705  static inline void
init_numa_balancing(unsigned long clone_flags,struct task_struct * p)1706  init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1707  {
1708  }
1709  #endif /* CONFIG_NUMA_BALANCING */
1710  
1711  #ifdef CONFIG_SMP
1712  
1713  static inline void
queue_balance_callback(struct rq * rq,struct callback_head * head,void (* func)(struct rq * rq))1714  queue_balance_callback(struct rq *rq,
1715  		       struct callback_head *head,
1716  		       void (*func)(struct rq *rq))
1717  {
1718  	lockdep_assert_rq_held(rq);
1719  
1720  	if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
1721  		return;
1722  
1723  	head->func = (void (*)(struct callback_head *))func;
1724  	head->next = rq->balance_callback;
1725  	rq->balance_callback = head;
1726  }
1727  
1728  #define rcu_dereference_check_sched_domain(p) \
1729  	rcu_dereference_check((p), \
1730  			      lockdep_is_held(&sched_domains_mutex))
1731  
1732  /*
1733   * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1734   * See destroy_sched_domains: call_rcu for details.
1735   *
1736   * The domain tree of any CPU may only be accessed from within
1737   * preempt-disabled sections.
1738   */
1739  #define for_each_domain(cpu, __sd) \
1740  	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1741  			__sd; __sd = __sd->parent)
1742  
1743  /**
1744   * highest_flag_domain - Return highest sched_domain containing flag.
1745   * @cpu:	The CPU whose highest level of sched domain is to
1746   *		be returned.
1747   * @flag:	The flag to check for the highest sched_domain
1748   *		for the given CPU.
1749   *
1750   * Returns the highest sched_domain of a CPU which contains the given flag.
1751   */
highest_flag_domain(int cpu,int flag)1752  static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1753  {
1754  	struct sched_domain *sd, *hsd = NULL;
1755  
1756  	for_each_domain(cpu, sd) {
1757  		if (!(sd->flags & flag))
1758  			break;
1759  		hsd = sd;
1760  	}
1761  
1762  	return hsd;
1763  }
1764  
lowest_flag_domain(int cpu,int flag)1765  static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1766  {
1767  	struct sched_domain *sd;
1768  
1769  	for_each_domain(cpu, sd) {
1770  		if (sd->flags & flag)
1771  			break;
1772  	}
1773  
1774  	return sd;
1775  }
1776  
1777  DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
1778  DECLARE_PER_CPU(int, sd_llc_size);
1779  DECLARE_PER_CPU(int, sd_llc_id);
1780  DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
1781  DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
1782  DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
1783  DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
1784  extern struct static_key_false sched_asym_cpucapacity;
1785  
1786  struct sched_group_capacity {
1787  	atomic_t		ref;
1788  	/*
1789  	 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
1790  	 * for a single CPU.
1791  	 */
1792  	unsigned long		capacity;
1793  	unsigned long		min_capacity;		/* Min per-CPU capacity in group */
1794  	unsigned long		max_capacity;		/* Max per-CPU capacity in group */
1795  	unsigned long		next_update;
1796  	int			imbalance;		/* XXX unrelated to capacity but shared group state */
1797  
1798  #ifdef CONFIG_SCHED_DEBUG
1799  	int			id;
1800  #endif
1801  
1802  	unsigned long		cpumask[];		/* Balance mask */
1803  };
1804  
1805  struct sched_group {
1806  	struct sched_group	*next;			/* Must be a circular list */
1807  	atomic_t		ref;
1808  
1809  	unsigned int		group_weight;
1810  	struct sched_group_capacity *sgc;
1811  	int			asym_prefer_cpu;	/* CPU of highest priority in group */
1812  
1813  	/*
1814  	 * The CPUs this group covers.
1815  	 *
1816  	 * NOTE: this field is variable length. (Allocated dynamically
1817  	 * by attaching extra space to the end of the structure,
1818  	 * depending on how many CPUs the kernel has booted up with)
1819  	 */
1820  	unsigned long		cpumask[];
1821  };
1822  
sched_group_span(struct sched_group * sg)1823  static inline struct cpumask *sched_group_span(struct sched_group *sg)
1824  {
1825  	return to_cpumask(sg->cpumask);
1826  }
1827  
1828  /*
1829   * See build_balance_mask().
1830   */
group_balance_mask(struct sched_group * sg)1831  static inline struct cpumask *group_balance_mask(struct sched_group *sg)
1832  {
1833  	return to_cpumask(sg->sgc->cpumask);
1834  }
1835  
1836  /**
1837   * group_first_cpu - Returns the first CPU in the cpumask of a sched_group.
1838   * @group: The group whose first CPU is to be returned.
1839   */
group_first_cpu(struct sched_group * group)1840  static inline unsigned int group_first_cpu(struct sched_group *group)
1841  {
1842  	return cpumask_first(sched_group_span(group));
1843  }
1844  
1845  extern int group_balance_cpu(struct sched_group *sg);
1846  
1847  #ifdef CONFIG_SCHED_DEBUG
1848  void update_sched_domain_debugfs(void);
1849  void dirty_sched_domain_sysctl(int cpu);
1850  #else
update_sched_domain_debugfs(void)1851  static inline void update_sched_domain_debugfs(void)
1852  {
1853  }
dirty_sched_domain_sysctl(int cpu)1854  static inline void dirty_sched_domain_sysctl(int cpu)
1855  {
1856  }
1857  #endif
1858  
1859  extern int sched_update_scaling(void);
1860  
1861  extern void flush_smp_call_function_from_idle(void);
1862  
1863  #else /* !CONFIG_SMP: */
flush_smp_call_function_from_idle(void)1864  static inline void flush_smp_call_function_from_idle(void) { }
1865  #endif
1866  
1867  #include "stats.h"
1868  #include "autogroup.h"
1869  
1870  #ifdef CONFIG_CGROUP_SCHED
1871  
1872  /*
1873   * Return the group to which this tasks belongs.
1874   *
1875   * We cannot use task_css() and friends because the cgroup subsystem
1876   * changes that value before the cgroup_subsys::attach() method is called,
1877   * therefore we cannot pin it and might observe the wrong value.
1878   *
1879   * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
1880   * core changes this before calling sched_move_task().
1881   *
1882   * Instead we use a 'copy' which is updated from sched_move_task() while
1883   * holding both task_struct::pi_lock and rq::lock.
1884   */
task_group(struct task_struct * p)1885  static inline struct task_group *task_group(struct task_struct *p)
1886  {
1887  	return p->sched_task_group;
1888  }
1889  
1890  /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
set_task_rq(struct task_struct * p,unsigned int cpu)1891  static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
1892  {
1893  #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
1894  	struct task_group *tg = task_group(p);
1895  #endif
1896  
1897  #ifdef CONFIG_FAIR_GROUP_SCHED
1898  	set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
1899  	p->se.cfs_rq = tg->cfs_rq[cpu];
1900  	p->se.parent = tg->se[cpu];
1901  #endif
1902  
1903  #ifdef CONFIG_RT_GROUP_SCHED
1904  	p->rt.rt_rq  = tg->rt_rq[cpu];
1905  	p->rt.parent = tg->rt_se[cpu];
1906  #endif
1907  }
1908  
1909  #else /* CONFIG_CGROUP_SCHED */
1910  
set_task_rq(struct task_struct * p,unsigned int cpu)1911  static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
task_group(struct task_struct * p)1912  static inline struct task_group *task_group(struct task_struct *p)
1913  {
1914  	return NULL;
1915  }
1916  
1917  #endif /* CONFIG_CGROUP_SCHED */
1918  
__set_task_cpu(struct task_struct * p,unsigned int cpu)1919  static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
1920  {
1921  	set_task_rq(p, cpu);
1922  #ifdef CONFIG_SMP
1923  	/*
1924  	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
1925  	 * successfully executed on another CPU. We must ensure that updates of
1926  	 * per-task data have been completed by this moment.
1927  	 */
1928  	smp_wmb();
1929  #ifdef CONFIG_THREAD_INFO_IN_TASK
1930  	WRITE_ONCE(p->cpu, cpu);
1931  #else
1932  	WRITE_ONCE(task_thread_info(p)->cpu, cpu);
1933  #endif
1934  	p->wake_cpu = cpu;
1935  #endif
1936  }
1937  
1938  /*
1939   * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
1940   */
1941  #ifdef CONFIG_SCHED_DEBUG
1942  # include <linux/static_key.h>
1943  # define const_debug __read_mostly
1944  #else
1945  # define const_debug const
1946  #endif
1947  
1948  #define SCHED_FEAT(name, enabled)	\
1949  	__SCHED_FEAT_##name ,
1950  
1951  enum {
1952  #include "features.h"
1953  	__SCHED_FEAT_NR,
1954  };
1955  
1956  #undef SCHED_FEAT
1957  
1958  #ifdef CONFIG_SCHED_DEBUG
1959  
1960  /*
1961   * To support run-time toggling of sched features, all the translation units
1962   * (but core.c) reference the sysctl_sched_features defined in core.c.
1963   */
1964  extern const_debug unsigned int sysctl_sched_features;
1965  
1966  #ifdef CONFIG_JUMP_LABEL
1967  #define SCHED_FEAT(name, enabled)					\
1968  static __always_inline bool static_branch_##name(struct static_key *key) \
1969  {									\
1970  	return static_key_##enabled(key);				\
1971  }
1972  
1973  #include "features.h"
1974  #undef SCHED_FEAT
1975  
1976  extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
1977  #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
1978  
1979  #else /* !CONFIG_JUMP_LABEL */
1980  
1981  #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1982  
1983  #endif /* CONFIG_JUMP_LABEL */
1984  
1985  #else /* !SCHED_DEBUG */
1986  
1987  /*
1988   * Each translation unit has its own copy of sysctl_sched_features to allow
1989   * constants propagation at compile time and compiler optimization based on
1990   * features default.
1991   */
1992  #define SCHED_FEAT(name, enabled)	\
1993  	(1UL << __SCHED_FEAT_##name) * enabled |
1994  static const_debug __maybe_unused unsigned int sysctl_sched_features =
1995  #include "features.h"
1996  	0;
1997  #undef SCHED_FEAT
1998  
1999  #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2000  
2001  #endif /* SCHED_DEBUG */
2002  
2003  extern struct static_key_false sched_numa_balancing;
2004  extern struct static_key_false sched_schedstats;
2005  
global_rt_period(void)2006  static inline u64 global_rt_period(void)
2007  {
2008  	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
2009  }
2010  
global_rt_runtime(void)2011  static inline u64 global_rt_runtime(void)
2012  {
2013  	if (sysctl_sched_rt_runtime < 0)
2014  		return RUNTIME_INF;
2015  
2016  	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
2017  }
2018  
task_current(struct rq * rq,struct task_struct * p)2019  static inline int task_current(struct rq *rq, struct task_struct *p)
2020  {
2021  	return rq->curr == p;
2022  }
2023  
task_running(struct rq * rq,struct task_struct * p)2024  static inline int task_running(struct rq *rq, struct task_struct *p)
2025  {
2026  #ifdef CONFIG_SMP
2027  	return p->on_cpu;
2028  #else
2029  	return task_current(rq, p);
2030  #endif
2031  }
2032  
task_on_rq_queued(struct task_struct * p)2033  static inline int task_on_rq_queued(struct task_struct *p)
2034  {
2035  	return p->on_rq == TASK_ON_RQ_QUEUED;
2036  }
2037  
task_on_rq_migrating(struct task_struct * p)2038  static inline int task_on_rq_migrating(struct task_struct *p)
2039  {
2040  	return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
2041  }
2042  
2043  /* Wake flags. The first three directly map to some SD flag value */
2044  #define WF_EXEC     0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
2045  #define WF_FORK     0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
2046  #define WF_TTWU     0x08 /* Wakeup;            maps to SD_BALANCE_WAKE */
2047  
2048  #define WF_SYNC     0x10 /* Waker goes to sleep after wakeup */
2049  #define WF_MIGRATED 0x20 /* Internal use, task got migrated */
2050  #define WF_ON_CPU   0x40 /* Wakee is on_cpu */
2051  
2052  #ifdef CONFIG_SMP
2053  static_assert(WF_EXEC == SD_BALANCE_EXEC);
2054  static_assert(WF_FORK == SD_BALANCE_FORK);
2055  static_assert(WF_TTWU == SD_BALANCE_WAKE);
2056  #endif
2057  
2058  /*
2059   * To aid in avoiding the subversion of "niceness" due to uneven distribution
2060   * of tasks with abnormal "nice" values across CPUs the contribution that
2061   * each task makes to its run queue's load is weighted according to its
2062   * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
2063   * scaled version of the new time slice allocation that they receive on time
2064   * slice expiry etc.
2065   */
2066  
2067  #define WEIGHT_IDLEPRIO		3
2068  #define WMULT_IDLEPRIO		1431655765
2069  
2070  extern const int		sched_prio_to_weight[40];
2071  extern const u32		sched_prio_to_wmult[40];
2072  
2073  /*
2074   * {de,en}queue flags:
2075   *
2076   * DEQUEUE_SLEEP  - task is no longer runnable
2077   * ENQUEUE_WAKEUP - task just became runnable
2078   *
2079   * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
2080   *                are in a known state which allows modification. Such pairs
2081   *                should preserve as much state as possible.
2082   *
2083   * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
2084   *        in the runqueue.
2085   *
2086   * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
2087   * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
2088   * ENQUEUE_MIGRATED  - the task was migrated during wakeup
2089   *
2090   */
2091  
2092  #define DEQUEUE_SLEEP		0x01
2093  #define DEQUEUE_SAVE		0x02 /* Matches ENQUEUE_RESTORE */
2094  #define DEQUEUE_MOVE		0x04 /* Matches ENQUEUE_MOVE */
2095  #define DEQUEUE_NOCLOCK		0x08 /* Matches ENQUEUE_NOCLOCK */
2096  
2097  #define ENQUEUE_WAKEUP		0x01
2098  #define ENQUEUE_RESTORE		0x02
2099  #define ENQUEUE_MOVE		0x04
2100  #define ENQUEUE_NOCLOCK		0x08
2101  
2102  #define ENQUEUE_HEAD		0x10
2103  #define ENQUEUE_REPLENISH	0x20
2104  #ifdef CONFIG_SMP
2105  #define ENQUEUE_MIGRATED	0x40
2106  #else
2107  #define ENQUEUE_MIGRATED	0x00
2108  #endif
2109  
2110  #define RETRY_TASK		((void *)-1UL)
2111  
2112  struct sched_class {
2113  
2114  #ifdef CONFIG_UCLAMP_TASK
2115  	int uclamp_enabled;
2116  #endif
2117  
2118  	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
2119  	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
2120  	void (*yield_task)   (struct rq *rq);
2121  	bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
2122  
2123  	void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags);
2124  
2125  	struct task_struct *(*pick_next_task)(struct rq *rq);
2126  
2127  	void (*put_prev_task)(struct rq *rq, struct task_struct *p);
2128  	void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
2129  
2130  #ifdef CONFIG_SMP
2131  	int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2132  	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
2133  
2134  	struct task_struct * (*pick_task)(struct rq *rq);
2135  
2136  	void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
2137  
2138  	void (*task_woken)(struct rq *this_rq, struct task_struct *task);
2139  
2140  	void (*set_cpus_allowed)(struct task_struct *p,
2141  				 const struct cpumask *newmask,
2142  				 u32 flags);
2143  
2144  	void (*rq_online)(struct rq *rq);
2145  	void (*rq_offline)(struct rq *rq);
2146  
2147  	struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
2148  #endif
2149  
2150  	void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
2151  	void (*task_fork)(struct task_struct *p);
2152  	void (*task_dead)(struct task_struct *p);
2153  
2154  	/*
2155  	 * The switched_from() call is allowed to drop rq->lock, therefore we
2156  	 * cannot assume the switched_from/switched_to pair is serialized by
2157  	 * rq->lock. They are however serialized by p->pi_lock.
2158  	 */
2159  	void (*switched_from)(struct rq *this_rq, struct task_struct *task);
2160  	void (*switched_to)  (struct rq *this_rq, struct task_struct *task);
2161  	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
2162  			      int oldprio);
2163  
2164  	unsigned int (*get_rr_interval)(struct rq *rq,
2165  					struct task_struct *task);
2166  
2167  	void (*update_curr)(struct rq *rq);
2168  
2169  #define TASK_SET_GROUP		0
2170  #define TASK_MOVE_GROUP		1
2171  
2172  #ifdef CONFIG_FAIR_GROUP_SCHED
2173  	void (*task_change_group)(struct task_struct *p, int type);
2174  #endif
2175  };
2176  
put_prev_task(struct rq * rq,struct task_struct * prev)2177  static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
2178  {
2179  	WARN_ON_ONCE(rq->curr != prev);
2180  	prev->sched_class->put_prev_task(rq, prev);
2181  }
2182  
set_next_task(struct rq * rq,struct task_struct * next)2183  static inline void set_next_task(struct rq *rq, struct task_struct *next)
2184  {
2185  	next->sched_class->set_next_task(rq, next, false);
2186  }
2187  
2188  
2189  /*
2190   * Helper to define a sched_class instance; each one is placed in a separate
2191   * section which is ordered by the linker script:
2192   *
2193   *   include/asm-generic/vmlinux.lds.h
2194   *
2195   * Also enforce alignment on the instance, not the type, to guarantee layout.
2196   */
2197  #define DEFINE_SCHED_CLASS(name) \
2198  const struct sched_class name##_sched_class \
2199  	__aligned(__alignof__(struct sched_class)) \
2200  	__section("__" #name "_sched_class")
2201  
2202  /* Defined in include/asm-generic/vmlinux.lds.h */
2203  extern struct sched_class __begin_sched_classes[];
2204  extern struct sched_class __end_sched_classes[];
2205  
2206  #define sched_class_highest (__end_sched_classes - 1)
2207  #define sched_class_lowest  (__begin_sched_classes - 1)
2208  
2209  #define for_class_range(class, _from, _to) \
2210  	for (class = (_from); class != (_to); class--)
2211  
2212  #define for_each_class(class) \
2213  	for_class_range(class, sched_class_highest, sched_class_lowest)
2214  
2215  extern const struct sched_class stop_sched_class;
2216  extern const struct sched_class dl_sched_class;
2217  extern const struct sched_class rt_sched_class;
2218  extern const struct sched_class fair_sched_class;
2219  extern const struct sched_class idle_sched_class;
2220  
sched_stop_runnable(struct rq * rq)2221  static inline bool sched_stop_runnable(struct rq *rq)
2222  {
2223  	return rq->stop && task_on_rq_queued(rq->stop);
2224  }
2225  
sched_dl_runnable(struct rq * rq)2226  static inline bool sched_dl_runnable(struct rq *rq)
2227  {
2228  	return rq->dl.dl_nr_running > 0;
2229  }
2230  
sched_rt_runnable(struct rq * rq)2231  static inline bool sched_rt_runnable(struct rq *rq)
2232  {
2233  	return rq->rt.rt_queued > 0;
2234  }
2235  
sched_fair_runnable(struct rq * rq)2236  static inline bool sched_fair_runnable(struct rq *rq)
2237  {
2238  	return rq->cfs.nr_running > 0;
2239  }
2240  
2241  extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2242  extern struct task_struct *pick_next_task_idle(struct rq *rq);
2243  
2244  #define SCA_CHECK		0x01
2245  #define SCA_MIGRATE_DISABLE	0x02
2246  #define SCA_MIGRATE_ENABLE	0x04
2247  #define SCA_USER		0x08
2248  
2249  #ifdef CONFIG_SMP
2250  
2251  extern void update_group_capacity(struct sched_domain *sd, int cpu);
2252  
2253  extern void trigger_load_balance(struct rq *rq);
2254  
2255  extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask, u32 flags);
2256  
get_push_task(struct rq * rq)2257  static inline struct task_struct *get_push_task(struct rq *rq)
2258  {
2259  	struct task_struct *p = rq->curr;
2260  
2261  	lockdep_assert_rq_held(rq);
2262  
2263  	if (rq->push_busy)
2264  		return NULL;
2265  
2266  	if (p->nr_cpus_allowed == 1)
2267  		return NULL;
2268  
2269  	if (p->migration_disabled)
2270  		return NULL;
2271  
2272  	rq->push_busy = true;
2273  	return get_task_struct(p);
2274  }
2275  
2276  extern int push_cpu_stop(void *arg);
2277  
2278  #endif
2279  
2280  #ifdef CONFIG_CPU_IDLE
idle_set_state(struct rq * rq,struct cpuidle_state * idle_state)2281  static inline void idle_set_state(struct rq *rq,
2282  				  struct cpuidle_state *idle_state)
2283  {
2284  	rq->idle_state = idle_state;
2285  }
2286  
idle_get_state(struct rq * rq)2287  static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2288  {
2289  	SCHED_WARN_ON(!rcu_read_lock_held());
2290  
2291  	return rq->idle_state;
2292  }
2293  #else
idle_set_state(struct rq * rq,struct cpuidle_state * idle_state)2294  static inline void idle_set_state(struct rq *rq,
2295  				  struct cpuidle_state *idle_state)
2296  {
2297  }
2298  
idle_get_state(struct rq * rq)2299  static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2300  {
2301  	return NULL;
2302  }
2303  #endif
2304  
2305  extern void schedule_idle(void);
2306  
2307  extern void sysrq_sched_debug_show(void);
2308  extern void sched_init_granularity(void);
2309  extern void update_max_interval(void);
2310  
2311  extern void init_sched_dl_class(void);
2312  extern void init_sched_rt_class(void);
2313  extern void init_sched_fair_class(void);
2314  
2315  extern void reweight_task(struct task_struct *p, int prio);
2316  
2317  extern void resched_curr(struct rq *rq);
2318  extern void resched_cpu(int cpu);
2319  
2320  extern struct rt_bandwidth def_rt_bandwidth;
2321  extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
2322  
2323  extern struct dl_bandwidth def_dl_bandwidth;
2324  extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
2325  extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
2326  extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se);
2327  
2328  #define BW_SHIFT		20
2329  #define BW_UNIT			(1 << BW_SHIFT)
2330  #define RATIO_SHIFT		8
2331  #define MAX_BW_BITS		(64 - BW_SHIFT)
2332  #define MAX_BW			((1ULL << MAX_BW_BITS) - 1)
2333  unsigned long to_ratio(u64 period, u64 runtime);
2334  
2335  extern void init_entity_runnable_average(struct sched_entity *se);
2336  extern void post_init_entity_util_avg(struct task_struct *p);
2337  
2338  #ifdef CONFIG_NO_HZ_FULL
2339  extern bool sched_can_stop_tick(struct rq *rq);
2340  extern int __init sched_tick_offload_init(void);
2341  
2342  /*
2343   * Tick may be needed by tasks in the runqueue depending on their policy and
2344   * requirements. If tick is needed, lets send the target an IPI to kick it out of
2345   * nohz mode if necessary.
2346   */
sched_update_tick_dependency(struct rq * rq)2347  static inline void sched_update_tick_dependency(struct rq *rq)
2348  {
2349  	int cpu = cpu_of(rq);
2350  
2351  	if (!tick_nohz_full_cpu(cpu))
2352  		return;
2353  
2354  	if (sched_can_stop_tick(rq))
2355  		tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
2356  	else
2357  		tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
2358  }
2359  #else
sched_tick_offload_init(void)2360  static inline int sched_tick_offload_init(void) { return 0; }
sched_update_tick_dependency(struct rq * rq)2361  static inline void sched_update_tick_dependency(struct rq *rq) { }
2362  #endif
2363  
add_nr_running(struct rq * rq,unsigned count)2364  static inline void add_nr_running(struct rq *rq, unsigned count)
2365  {
2366  	unsigned prev_nr = rq->nr_running;
2367  
2368  	rq->nr_running = prev_nr + count;
2369  	if (trace_sched_update_nr_running_tp_enabled()) {
2370  		call_trace_sched_update_nr_running(rq, count);
2371  	}
2372  
2373  #ifdef CONFIG_SMP
2374  	if (prev_nr < 2 && rq->nr_running >= 2) {
2375  		if (!READ_ONCE(rq->rd->overload))
2376  			WRITE_ONCE(rq->rd->overload, 1);
2377  	}
2378  #endif
2379  
2380  	sched_update_tick_dependency(rq);
2381  }
2382  
sub_nr_running(struct rq * rq,unsigned count)2383  static inline void sub_nr_running(struct rq *rq, unsigned count)
2384  {
2385  	rq->nr_running -= count;
2386  	if (trace_sched_update_nr_running_tp_enabled()) {
2387  		call_trace_sched_update_nr_running(rq, -count);
2388  	}
2389  
2390  	/* Check if we still need preemption */
2391  	sched_update_tick_dependency(rq);
2392  }
2393  
2394  extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
2395  extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
2396  
2397  extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
2398  
2399  extern const_debug unsigned int sysctl_sched_nr_migrate;
2400  extern const_debug unsigned int sysctl_sched_migration_cost;
2401  
2402  #ifdef CONFIG_SCHED_DEBUG
2403  extern unsigned int sysctl_sched_latency;
2404  extern unsigned int sysctl_sched_min_granularity;
2405  extern unsigned int sysctl_sched_wakeup_granularity;
2406  extern int sysctl_resched_latency_warn_ms;
2407  extern int sysctl_resched_latency_warn_once;
2408  
2409  extern unsigned int sysctl_sched_tunable_scaling;
2410  
2411  extern unsigned int sysctl_numa_balancing_scan_delay;
2412  extern unsigned int sysctl_numa_balancing_scan_period_min;
2413  extern unsigned int sysctl_numa_balancing_scan_period_max;
2414  extern unsigned int sysctl_numa_balancing_scan_size;
2415  #endif
2416  
2417  #ifdef CONFIG_SCHED_HRTICK
2418  
2419  /*
2420   * Use hrtick when:
2421   *  - enabled by features
2422   *  - hrtimer is actually high res
2423   */
hrtick_enabled(struct rq * rq)2424  static inline int hrtick_enabled(struct rq *rq)
2425  {
2426  	if (!cpu_active(cpu_of(rq)))
2427  		return 0;
2428  	return hrtimer_is_hres_active(&rq->hrtick_timer);
2429  }
2430  
hrtick_enabled_fair(struct rq * rq)2431  static inline int hrtick_enabled_fair(struct rq *rq)
2432  {
2433  	if (!sched_feat(HRTICK))
2434  		return 0;
2435  	return hrtick_enabled(rq);
2436  }
2437  
hrtick_enabled_dl(struct rq * rq)2438  static inline int hrtick_enabled_dl(struct rq *rq)
2439  {
2440  	if (!sched_feat(HRTICK_DL))
2441  		return 0;
2442  	return hrtick_enabled(rq);
2443  }
2444  
2445  void hrtick_start(struct rq *rq, u64 delay);
2446  
2447  #else
2448  
hrtick_enabled_fair(struct rq * rq)2449  static inline int hrtick_enabled_fair(struct rq *rq)
2450  {
2451  	return 0;
2452  }
2453  
hrtick_enabled_dl(struct rq * rq)2454  static inline int hrtick_enabled_dl(struct rq *rq)
2455  {
2456  	return 0;
2457  }
2458  
hrtick_enabled(struct rq * rq)2459  static inline int hrtick_enabled(struct rq *rq)
2460  {
2461  	return 0;
2462  }
2463  
2464  #endif /* CONFIG_SCHED_HRTICK */
2465  
2466  #ifndef arch_scale_freq_tick
2467  static __always_inline
arch_scale_freq_tick(void)2468  void arch_scale_freq_tick(void)
2469  {
2470  }
2471  #endif
2472  
2473  #ifndef arch_scale_freq_capacity
2474  /**
2475   * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
2476   * @cpu: the CPU in question.
2477   *
2478   * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
2479   *
2480   *     f_curr
2481   *     ------ * SCHED_CAPACITY_SCALE
2482   *     f_max
2483   */
2484  static __always_inline
arch_scale_freq_capacity(int cpu)2485  unsigned long arch_scale_freq_capacity(int cpu)
2486  {
2487  	return SCHED_CAPACITY_SCALE;
2488  }
2489  #endif
2490  
2491  
2492  #ifdef CONFIG_SMP
2493  
rq_order_less(struct rq * rq1,struct rq * rq2)2494  static inline bool rq_order_less(struct rq *rq1, struct rq *rq2)
2495  {
2496  #ifdef CONFIG_SCHED_CORE
2497  	/*
2498  	 * In order to not have {0,2},{1,3} turn into into an AB-BA,
2499  	 * order by core-id first and cpu-id second.
2500  	 *
2501  	 * Notably:
2502  	 *
2503  	 *	double_rq_lock(0,3); will take core-0, core-1 lock
2504  	 *	double_rq_lock(1,2); will take core-1, core-0 lock
2505  	 *
2506  	 * when only cpu-id is considered.
2507  	 */
2508  	if (rq1->core->cpu < rq2->core->cpu)
2509  		return true;
2510  	if (rq1->core->cpu > rq2->core->cpu)
2511  		return false;
2512  
2513  	/*
2514  	 * __sched_core_flip() relies on SMT having cpu-id lock order.
2515  	 */
2516  #endif
2517  	return rq1->cpu < rq2->cpu;
2518  }
2519  
2520  extern void double_rq_lock(struct rq *rq1, struct rq *rq2);
2521  
2522  #ifdef CONFIG_PREEMPTION
2523  
2524  /*
2525   * fair double_lock_balance: Safely acquires both rq->locks in a fair
2526   * way at the expense of forcing extra atomic operations in all
2527   * invocations.  This assures that the double_lock is acquired using the
2528   * same underlying policy as the spinlock_t on this architecture, which
2529   * reduces latency compared to the unfair variant below.  However, it
2530   * also adds more overhead and therefore may reduce throughput.
2531   */
_double_lock_balance(struct rq * this_rq,struct rq * busiest)2532  static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2533  	__releases(this_rq->lock)
2534  	__acquires(busiest->lock)
2535  	__acquires(this_rq->lock)
2536  {
2537  	raw_spin_rq_unlock(this_rq);
2538  	double_rq_lock(this_rq, busiest);
2539  
2540  	return 1;
2541  }
2542  
2543  #else
2544  /*
2545   * Unfair double_lock_balance: Optimizes throughput at the expense of
2546   * latency by eliminating extra atomic operations when the locks are
2547   * already in proper order on entry.  This favors lower CPU-ids and will
2548   * grant the double lock to lower CPUs over higher ids under contention,
2549   * regardless of entry order into the function.
2550   */
_double_lock_balance(struct rq * this_rq,struct rq * busiest)2551  static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2552  	__releases(this_rq->lock)
2553  	__acquires(busiest->lock)
2554  	__acquires(this_rq->lock)
2555  {
2556  	if (__rq_lockp(this_rq) == __rq_lockp(busiest))
2557  		return 0;
2558  
2559  	if (likely(raw_spin_rq_trylock(busiest)))
2560  		return 0;
2561  
2562  	if (rq_order_less(this_rq, busiest)) {
2563  		raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING);
2564  		return 0;
2565  	}
2566  
2567  	raw_spin_rq_unlock(this_rq);
2568  	double_rq_lock(this_rq, busiest);
2569  
2570  	return 1;
2571  }
2572  
2573  #endif /* CONFIG_PREEMPTION */
2574  
2575  /*
2576   * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
2577   */
double_lock_balance(struct rq * this_rq,struct rq * busiest)2578  static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
2579  {
2580  	lockdep_assert_irqs_disabled();
2581  
2582  	return _double_lock_balance(this_rq, busiest);
2583  }
2584  
double_unlock_balance(struct rq * this_rq,struct rq * busiest)2585  static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
2586  	__releases(busiest->lock)
2587  {
2588  	if (__rq_lockp(this_rq) != __rq_lockp(busiest))
2589  		raw_spin_rq_unlock(busiest);
2590  	lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_);
2591  }
2592  
double_lock(spinlock_t * l1,spinlock_t * l2)2593  static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
2594  {
2595  	if (l1 > l2)
2596  		swap(l1, l2);
2597  
2598  	spin_lock(l1);
2599  	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2600  }
2601  
double_lock_irq(spinlock_t * l1,spinlock_t * l2)2602  static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
2603  {
2604  	if (l1 > l2)
2605  		swap(l1, l2);
2606  
2607  	spin_lock_irq(l1);
2608  	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2609  }
2610  
double_raw_lock(raw_spinlock_t * l1,raw_spinlock_t * l2)2611  static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
2612  {
2613  	if (l1 > l2)
2614  		swap(l1, l2);
2615  
2616  	raw_spin_lock(l1);
2617  	raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2618  }
2619  
2620  /*
2621   * double_rq_unlock - safely unlock two runqueues
2622   *
2623   * Note this does not restore interrupts like task_rq_unlock,
2624   * you need to do so manually after calling.
2625   */
double_rq_unlock(struct rq * rq1,struct rq * rq2)2626  static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2627  	__releases(rq1->lock)
2628  	__releases(rq2->lock)
2629  {
2630  	if (__rq_lockp(rq1) != __rq_lockp(rq2))
2631  		raw_spin_rq_unlock(rq2);
2632  	else
2633  		__release(rq2->lock);
2634  	raw_spin_rq_unlock(rq1);
2635  }
2636  
2637  extern void set_rq_online (struct rq *rq);
2638  extern void set_rq_offline(struct rq *rq);
2639  extern bool sched_smp_initialized;
2640  
2641  #else /* CONFIG_SMP */
2642  
2643  /*
2644   * double_rq_lock - safely lock two runqueues
2645   *
2646   * Note this does not disable interrupts like task_rq_lock,
2647   * you need to do so manually before calling.
2648   */
double_rq_lock(struct rq * rq1,struct rq * rq2)2649  static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2650  	__acquires(rq1->lock)
2651  	__acquires(rq2->lock)
2652  {
2653  	BUG_ON(!irqs_disabled());
2654  	BUG_ON(rq1 != rq2);
2655  	raw_spin_rq_lock(rq1);
2656  	__acquire(rq2->lock);	/* Fake it out ;) */
2657  }
2658  
2659  /*
2660   * double_rq_unlock - safely unlock two runqueues
2661   *
2662   * Note this does not restore interrupts like task_rq_unlock,
2663   * you need to do so manually after calling.
2664   */
double_rq_unlock(struct rq * rq1,struct rq * rq2)2665  static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2666  	__releases(rq1->lock)
2667  	__releases(rq2->lock)
2668  {
2669  	BUG_ON(rq1 != rq2);
2670  	raw_spin_rq_unlock(rq1);
2671  	__release(rq2->lock);
2672  }
2673  
2674  #endif
2675  
2676  extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
2677  extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
2678  
2679  #ifdef	CONFIG_SCHED_DEBUG
2680  extern bool sched_debug_verbose;
2681  
2682  extern void print_cfs_stats(struct seq_file *m, int cpu);
2683  extern void print_rt_stats(struct seq_file *m, int cpu);
2684  extern void print_dl_stats(struct seq_file *m, int cpu);
2685  extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
2686  extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
2687  extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
2688  
2689  extern void resched_latency_warn(int cpu, u64 latency);
2690  #ifdef CONFIG_NUMA_BALANCING
2691  extern void
2692  show_numa_stats(struct task_struct *p, struct seq_file *m);
2693  extern void
2694  print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
2695  	unsigned long tpf, unsigned long gsf, unsigned long gpf);
2696  #endif /* CONFIG_NUMA_BALANCING */
2697  #else
resched_latency_warn(int cpu,u64 latency)2698  static inline void resched_latency_warn(int cpu, u64 latency) {}
2699  #endif /* CONFIG_SCHED_DEBUG */
2700  
2701  extern void init_cfs_rq(struct cfs_rq *cfs_rq);
2702  extern void init_rt_rq(struct rt_rq *rt_rq);
2703  extern void init_dl_rq(struct dl_rq *dl_rq);
2704  
2705  extern void cfs_bandwidth_usage_inc(void);
2706  extern void cfs_bandwidth_usage_dec(void);
2707  
2708  #ifdef CONFIG_NO_HZ_COMMON
2709  #define NOHZ_BALANCE_KICK_BIT	0
2710  #define NOHZ_STATS_KICK_BIT	1
2711  #define NOHZ_NEWILB_KICK_BIT	2
2712  
2713  #define NOHZ_BALANCE_KICK	BIT(NOHZ_BALANCE_KICK_BIT)
2714  #define NOHZ_STATS_KICK		BIT(NOHZ_STATS_KICK_BIT)
2715  #define NOHZ_NEWILB_KICK	BIT(NOHZ_NEWILB_KICK_BIT)
2716  
2717  #define NOHZ_KICK_MASK	(NOHZ_BALANCE_KICK | NOHZ_STATS_KICK)
2718  
2719  #define nohz_flags(cpu)	(&cpu_rq(cpu)->nohz_flags)
2720  
2721  extern void nohz_balance_exit_idle(struct rq *rq);
2722  #else
nohz_balance_exit_idle(struct rq * rq)2723  static inline void nohz_balance_exit_idle(struct rq *rq) { }
2724  #endif
2725  
2726  #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
2727  extern void nohz_run_idle_balance(int cpu);
2728  #else
nohz_run_idle_balance(int cpu)2729  static inline void nohz_run_idle_balance(int cpu) { }
2730  #endif
2731  
2732  #ifdef CONFIG_SMP
2733  static inline
__dl_update(struct dl_bw * dl_b,s64 bw)2734  void __dl_update(struct dl_bw *dl_b, s64 bw)
2735  {
2736  	struct root_domain *rd = container_of(dl_b, struct root_domain, dl_bw);
2737  	int i;
2738  
2739  	RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
2740  			 "sched RCU must be held");
2741  	for_each_cpu_and(i, rd->span, cpu_active_mask) {
2742  		struct rq *rq = cpu_rq(i);
2743  
2744  		rq->dl.extra_bw += bw;
2745  	}
2746  }
2747  #else
2748  static inline
__dl_update(struct dl_bw * dl_b,s64 bw)2749  void __dl_update(struct dl_bw *dl_b, s64 bw)
2750  {
2751  	struct dl_rq *dl = container_of(dl_b, struct dl_rq, dl_bw);
2752  
2753  	dl->extra_bw += bw;
2754  }
2755  #endif
2756  
2757  
2758  #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2759  struct irqtime {
2760  	u64			total;
2761  	u64			tick_delta;
2762  	u64			irq_start_time;
2763  	struct u64_stats_sync	sync;
2764  };
2765  
2766  DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
2767  
2768  /*
2769   * Returns the irqtime minus the softirq time computed by ksoftirqd.
2770   * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime
2771   * and never move forward.
2772   */
irq_time_read(int cpu)2773  static inline u64 irq_time_read(int cpu)
2774  {
2775  	struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
2776  	unsigned int seq;
2777  	u64 total;
2778  
2779  	do {
2780  		seq = __u64_stats_fetch_begin(&irqtime->sync);
2781  		total = irqtime->total;
2782  	} while (__u64_stats_fetch_retry(&irqtime->sync, seq));
2783  
2784  	return total;
2785  }
2786  #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
2787  
2788  #ifdef CONFIG_CPU_FREQ
2789  DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
2790  
2791  /**
2792   * cpufreq_update_util - Take a note about CPU utilization changes.
2793   * @rq: Runqueue to carry out the update for.
2794   * @flags: Update reason flags.
2795   *
2796   * This function is called by the scheduler on the CPU whose utilization is
2797   * being updated.
2798   *
2799   * It can only be called from RCU-sched read-side critical sections.
2800   *
2801   * The way cpufreq is currently arranged requires it to evaluate the CPU
2802   * performance state (frequency/voltage) on a regular basis to prevent it from
2803   * being stuck in a completely inadequate performance level for too long.
2804   * That is not guaranteed to happen if the updates are only triggered from CFS
2805   * and DL, though, because they may not be coming in if only RT tasks are
2806   * active all the time (or there are RT tasks only).
2807   *
2808   * As a workaround for that issue, this function is called periodically by the
2809   * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
2810   * but that really is a band-aid.  Going forward it should be replaced with
2811   * solutions targeted more specifically at RT tasks.
2812   */
cpufreq_update_util(struct rq * rq,unsigned int flags)2813  static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
2814  {
2815  	struct update_util_data *data;
2816  
2817  	data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
2818  						  cpu_of(rq)));
2819  	if (data)
2820  		data->func(data, rq_clock(rq), flags);
2821  }
2822  #else
cpufreq_update_util(struct rq * rq,unsigned int flags)2823  static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
2824  #endif /* CONFIG_CPU_FREQ */
2825  
2826  #ifdef CONFIG_UCLAMP_TASK
2827  unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
2828  
2829  /**
2830   * uclamp_rq_util_with - clamp @util with @rq and @p effective uclamp values.
2831   * @rq:		The rq to clamp against. Must not be NULL.
2832   * @util:	The util value to clamp.
2833   * @p:		The task to clamp against. Can be NULL if you want to clamp
2834   *		against @rq only.
2835   *
2836   * Clamps the passed @util to the max(@rq, @p) effective uclamp values.
2837   *
2838   * If sched_uclamp_used static key is disabled, then just return the util
2839   * without any clamping since uclamp aggregation at the rq level in the fast
2840   * path is disabled, rendering this operation a NOP.
2841   *
2842   * Use uclamp_eff_value() if you don't care about uclamp values at rq level. It
2843   * will return the correct effective uclamp value of the task even if the
2844   * static key is disabled.
2845   */
2846  static __always_inline
uclamp_rq_util_with(struct rq * rq,unsigned long util,struct task_struct * p)2847  unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
2848  				  struct task_struct *p)
2849  {
2850  	unsigned long min_util = 0;
2851  	unsigned long max_util = 0;
2852  
2853  	if (!static_branch_likely(&sched_uclamp_used))
2854  		return util;
2855  
2856  	if (p) {
2857  		min_util = uclamp_eff_value(p, UCLAMP_MIN);
2858  		max_util = uclamp_eff_value(p, UCLAMP_MAX);
2859  
2860  		/*
2861  		 * Ignore last runnable task's max clamp, as this task will
2862  		 * reset it. Similarly, no need to read the rq's min clamp.
2863  		 */
2864  		if (rq->uclamp_flags & UCLAMP_FLAG_IDLE)
2865  			goto out;
2866  	}
2867  
2868  	min_util = max_t(unsigned long, min_util, READ_ONCE(rq->uclamp[UCLAMP_MIN].value));
2869  	max_util = max_t(unsigned long, max_util, READ_ONCE(rq->uclamp[UCLAMP_MAX].value));
2870  out:
2871  	/*
2872  	 * Since CPU's {min,max}_util clamps are MAX aggregated considering
2873  	 * RUNNABLE tasks with _different_ clamps, we can end up with an
2874  	 * inversion. Fix it now when the clamps are applied.
2875  	 */
2876  	if (unlikely(min_util >= max_util))
2877  		return min_util;
2878  
2879  	return clamp(util, min_util, max_util);
2880  }
2881  
2882  /*
2883   * When uclamp is compiled in, the aggregation at rq level is 'turned off'
2884   * by default in the fast path and only gets turned on once userspace performs
2885   * an operation that requires it.
2886   *
2887   * Returns true if userspace opted-in to use uclamp and aggregation at rq level
2888   * hence is active.
2889   */
uclamp_is_used(void)2890  static inline bool uclamp_is_used(void)
2891  {
2892  	return static_branch_likely(&sched_uclamp_used);
2893  }
2894  #else /* CONFIG_UCLAMP_TASK */
2895  static inline
uclamp_rq_util_with(struct rq * rq,unsigned long util,struct task_struct * p)2896  unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
2897  				  struct task_struct *p)
2898  {
2899  	return util;
2900  }
2901  
uclamp_is_used(void)2902  static inline bool uclamp_is_used(void)
2903  {
2904  	return false;
2905  }
2906  #endif /* CONFIG_UCLAMP_TASK */
2907  
2908  #ifdef arch_scale_freq_capacity
2909  # ifndef arch_scale_freq_invariant
2910  #  define arch_scale_freq_invariant()	true
2911  # endif
2912  #else
2913  # define arch_scale_freq_invariant()	false
2914  #endif
2915  
2916  #ifdef CONFIG_SMP
capacity_orig_of(int cpu)2917  static inline unsigned long capacity_orig_of(int cpu)
2918  {
2919  	return cpu_rq(cpu)->cpu_capacity_orig;
2920  }
2921  
2922  /**
2923   * enum cpu_util_type - CPU utilization type
2924   * @FREQUENCY_UTIL:	Utilization used to select frequency
2925   * @ENERGY_UTIL:	Utilization used during energy calculation
2926   *
2927   * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time
2928   * need to be aggregated differently depending on the usage made of them. This
2929   * enum is used within effective_cpu_util() to differentiate the types of
2930   * utilization expected by the callers, and adjust the aggregation accordingly.
2931   */
2932  enum cpu_util_type {
2933  	FREQUENCY_UTIL,
2934  	ENERGY_UTIL,
2935  };
2936  
2937  unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
2938  				 unsigned long max, enum cpu_util_type type,
2939  				 struct task_struct *p);
2940  
cpu_bw_dl(struct rq * rq)2941  static inline unsigned long cpu_bw_dl(struct rq *rq)
2942  {
2943  	return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
2944  }
2945  
cpu_util_dl(struct rq * rq)2946  static inline unsigned long cpu_util_dl(struct rq *rq)
2947  {
2948  	return READ_ONCE(rq->avg_dl.util_avg);
2949  }
2950  
cpu_util_cfs(struct rq * rq)2951  static inline unsigned long cpu_util_cfs(struct rq *rq)
2952  {
2953  	unsigned long util = READ_ONCE(rq->cfs.avg.util_avg);
2954  
2955  	if (sched_feat(UTIL_EST)) {
2956  		util = max_t(unsigned long, util,
2957  			     READ_ONCE(rq->cfs.avg.util_est.enqueued));
2958  	}
2959  
2960  	return util;
2961  }
2962  
cpu_util_rt(struct rq * rq)2963  static inline unsigned long cpu_util_rt(struct rq *rq)
2964  {
2965  	return READ_ONCE(rq->avg_rt.util_avg);
2966  }
2967  #endif
2968  
2969  #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
cpu_util_irq(struct rq * rq)2970  static inline unsigned long cpu_util_irq(struct rq *rq)
2971  {
2972  	return rq->avg_irq.util_avg;
2973  }
2974  
2975  static inline
scale_irq_capacity(unsigned long util,unsigned long irq,unsigned long max)2976  unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2977  {
2978  	util *= (max - irq);
2979  	util /= max;
2980  
2981  	return util;
2982  
2983  }
2984  #else
cpu_util_irq(struct rq * rq)2985  static inline unsigned long cpu_util_irq(struct rq *rq)
2986  {
2987  	return 0;
2988  }
2989  
2990  static inline
scale_irq_capacity(unsigned long util,unsigned long irq,unsigned long max)2991  unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2992  {
2993  	return util;
2994  }
2995  #endif
2996  
2997  #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
2998  
2999  #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
3000  
3001  DECLARE_STATIC_KEY_FALSE(sched_energy_present);
3002  
sched_energy_enabled(void)3003  static inline bool sched_energy_enabled(void)
3004  {
3005  	return static_branch_unlikely(&sched_energy_present);
3006  }
3007  
3008  #else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
3009  
3010  #define perf_domain_span(pd) NULL
sched_energy_enabled(void)3011  static inline bool sched_energy_enabled(void) { return false; }
3012  
3013  #endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
3014  
3015  #ifdef CONFIG_MEMBARRIER
3016  /*
3017   * The scheduler provides memory barriers required by membarrier between:
3018   * - prior user-space memory accesses and store to rq->membarrier_state,
3019   * - store to rq->membarrier_state and following user-space memory accesses.
3020   * In the same way it provides those guarantees around store to rq->curr.
3021   */
membarrier_switch_mm(struct rq * rq,struct mm_struct * prev_mm,struct mm_struct * next_mm)3022  static inline void membarrier_switch_mm(struct rq *rq,
3023  					struct mm_struct *prev_mm,
3024  					struct mm_struct *next_mm)
3025  {
3026  	int membarrier_state;
3027  
3028  	if (prev_mm == next_mm)
3029  		return;
3030  
3031  	membarrier_state = atomic_read(&next_mm->membarrier_state);
3032  	if (READ_ONCE(rq->membarrier_state) == membarrier_state)
3033  		return;
3034  
3035  	WRITE_ONCE(rq->membarrier_state, membarrier_state);
3036  }
3037  #else
membarrier_switch_mm(struct rq * rq,struct mm_struct * prev_mm,struct mm_struct * next_mm)3038  static inline void membarrier_switch_mm(struct rq *rq,
3039  					struct mm_struct *prev_mm,
3040  					struct mm_struct *next_mm)
3041  {
3042  }
3043  #endif
3044  
3045  #ifdef CONFIG_SMP
is_per_cpu_kthread(struct task_struct * p)3046  static inline bool is_per_cpu_kthread(struct task_struct *p)
3047  {
3048  	if (!(p->flags & PF_KTHREAD))
3049  		return false;
3050  
3051  	if (p->nr_cpus_allowed != 1)
3052  		return false;
3053  
3054  	return true;
3055  }
3056  #endif
3057  
3058  extern void swake_up_all_locked(struct swait_queue_head *q);
3059  extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
3060  
3061  #ifdef CONFIG_PREEMPT_DYNAMIC
3062  extern int preempt_dynamic_mode;
3063  extern int sched_dynamic_mode(const char *str);
3064  extern void sched_dynamic_update(int mode);
3065  #endif
3066  
3067