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