1  /* SPDX-License-Identifier: GPL-2.0 */
2  /*
3   * Scheduler internal types and methods:
4   */
5  #ifndef _KERNEL_SCHED_SCHED_H
6  #define _KERNEL_SCHED_SCHED_H
7  
8  #include <linux/sched/affinity.h>
9  #include <linux/sched/autogroup.h>
10  #include <linux/sched/cpufreq.h>
11  #include <linux/sched/deadline.h>
12  #include <linux/sched.h>
13  #include <linux/sched/loadavg.h>
14  #include <linux/sched/mm.h>
15  #include <linux/sched/rseq_api.h>
16  #include <linux/sched/signal.h>
17  #include <linux/sched/smt.h>
18  #include <linux/sched/stat.h>
19  #include <linux/sched/sysctl.h>
20  #include <linux/sched/task_flags.h>
21  #include <linux/sched/task.h>
22  #include <linux/sched/topology.h>
23  
24  #include <linux/atomic.h>
25  #include <linux/bitmap.h>
26  #include <linux/bug.h>
27  #include <linux/capability.h>
28  #include <linux/cgroup_api.h>
29  #include <linux/cgroup.h>
30  #include <linux/context_tracking.h>
31  #include <linux/cpufreq.h>
32  #include <linux/cpumask_api.h>
33  #include <linux/ctype.h>
34  #include <linux/file.h>
35  #include <linux/fs_api.h>
36  #include <linux/hrtimer_api.h>
37  #include <linux/interrupt.h>
38  #include <linux/irq_work.h>
39  #include <linux/jiffies.h>
40  #include <linux/kref_api.h>
41  #include <linux/kthread.h>
42  #include <linux/ktime_api.h>
43  #include <linux/lockdep_api.h>
44  #include <linux/lockdep.h>
45  #include <linux/minmax.h>
46  #include <linux/mm.h>
47  #include <linux/module.h>
48  #include <linux/mutex_api.h>
49  #include <linux/plist.h>
50  #include <linux/poll.h>
51  #include <linux/proc_fs.h>
52  #include <linux/profile.h>
53  #include <linux/psi.h>
54  #include <linux/rcupdate.h>
55  #include <linux/seq_file.h>
56  #include <linux/seqlock.h>
57  #include <linux/softirq.h>
58  #include <linux/spinlock_api.h>
59  #include <linux/static_key.h>
60  #include <linux/stop_machine.h>
61  #include <linux/syscalls_api.h>
62  #include <linux/syscalls.h>
63  #include <linux/tick.h>
64  #include <linux/topology.h>
65  #include <linux/types.h>
66  #include <linux/u64_stats_sync_api.h>
67  #include <linux/uaccess.h>
68  #include <linux/wait_api.h>
69  #include <linux/wait_bit.h>
70  #include <linux/workqueue_api.h>
71  #include <linux/delayacct.h>
72  
73  #include <trace/events/power.h>
74  #include <trace/events/sched.h>
75  
76  #include "../workqueue_internal.h"
77  
78  struct rq;
79  struct cfs_rq;
80  struct rt_rq;
81  struct sched_group;
82  struct cpuidle_state;
83  
84  #ifdef CONFIG_PARAVIRT
85  # include <asm/paravirt.h>
86  # include <asm/paravirt_api_clock.h>
87  #endif
88  
89  #include <asm/barrier.h>
90  
91  #include "cpupri.h"
92  #include "cpudeadline.h"
93  
94  #ifdef CONFIG_SCHED_DEBUG
95  # define SCHED_WARN_ON(x)      WARN_ONCE(x, #x)
96  #else
97  # define SCHED_WARN_ON(x)      ({ (void)(x), 0; })
98  #endif
99  
100  /* task_struct::on_rq states: */
101  #define TASK_ON_RQ_QUEUED	1
102  #define TASK_ON_RQ_MIGRATING	2
103  
104  extern __read_mostly int scheduler_running;
105  
106  extern unsigned long calc_load_update;
107  extern atomic_long_t calc_load_tasks;
108  
109  extern void calc_global_load_tick(struct rq *this_rq);
110  extern long calc_load_fold_active(struct rq *this_rq, long adjust);
111  
112  extern void call_trace_sched_update_nr_running(struct rq *rq, int count);
113  
114  extern int sysctl_sched_rt_period;
115  extern int sysctl_sched_rt_runtime;
116  extern int sched_rr_timeslice;
117  
118  /*
119   * Asymmetric CPU capacity bits
120   */
121  struct asym_cap_data {
122  	struct list_head link;
123  	struct rcu_head rcu;
124  	unsigned long capacity;
125  	unsigned long cpus[];
126  };
127  
128  extern struct list_head asym_cap_list;
129  
130  #define cpu_capacity_span(asym_data) to_cpumask((asym_data)->cpus)
131  
132  /*
133   * Helpers for converting nanosecond timing to jiffy resolution
134   */
135  #define NS_TO_JIFFIES(time)	((unsigned long)(time) / (NSEC_PER_SEC/HZ))
136  
137  /*
138   * Increase resolution of nice-level calculations for 64-bit architectures.
139   * The extra resolution improves shares distribution and load balancing of
140   * low-weight task groups (eg. nice +19 on an autogroup), deeper task-group
141   * hierarchies, especially on larger systems. This is not a user-visible change
142   * and does not change the user-interface for setting shares/weights.
143   *
144   * We increase resolution only if we have enough bits to allow this increased
145   * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
146   * are pretty high and the returns do not justify the increased costs.
147   *
148   * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
149   * increase coverage and consistency always enable it on 64-bit platforms.
150   */
151  #ifdef CONFIG_64BIT
152  # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
153  # define scale_load(w)		((w) << SCHED_FIXEDPOINT_SHIFT)
154  # define scale_load_down(w)					\
155  ({								\
156  	unsigned long __w = (w);				\
157  								\
158  	if (__w)						\
159  		__w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT);	\
160  	__w;							\
161  })
162  #else
163  # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT)
164  # define scale_load(w)		(w)
165  # define scale_load_down(w)	(w)
166  #endif
167  
168  /*
169   * Task weight (visible to users) and its load (invisible to users) have
170   * independent resolution, but they should be well calibrated. We use
171   * scale_load() and scale_load_down(w) to convert between them. The
172   * following must be true:
173   *
174   *  scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD
175   *
176   */
177  #define NICE_0_LOAD		(1L << NICE_0_LOAD_SHIFT)
178  
179  /*
180   * Single value that decides SCHED_DEADLINE internal math precision.
181   * 10 -> just above 1us
182   * 9  -> just above 0.5us
183   */
184  #define DL_SCALE		10
185  
186  /*
187   * Single value that denotes runtime == period, ie unlimited time.
188   */
189  #define RUNTIME_INF		((u64)~0ULL)
190  
idle_policy(int policy)191  static inline int idle_policy(int policy)
192  {
193  	return policy == SCHED_IDLE;
194  }
195  
normal_policy(int policy)196  static inline int normal_policy(int policy)
197  {
198  #ifdef CONFIG_SCHED_CLASS_EXT
199  	if (policy == SCHED_EXT)
200  		return true;
201  #endif
202  	return policy == SCHED_NORMAL;
203  }
204  
fair_policy(int policy)205  static inline int fair_policy(int policy)
206  {
207  	return normal_policy(policy) || policy == SCHED_BATCH;
208  }
209  
rt_policy(int policy)210  static inline int rt_policy(int policy)
211  {
212  	return policy == SCHED_FIFO || policy == SCHED_RR;
213  }
214  
dl_policy(int policy)215  static inline int dl_policy(int policy)
216  {
217  	return policy == SCHED_DEADLINE;
218  }
219  
valid_policy(int policy)220  static inline bool valid_policy(int policy)
221  {
222  	return idle_policy(policy) || fair_policy(policy) ||
223  		rt_policy(policy) || dl_policy(policy);
224  }
225  
task_has_idle_policy(struct task_struct * p)226  static inline int task_has_idle_policy(struct task_struct *p)
227  {
228  	return idle_policy(p->policy);
229  }
230  
task_has_rt_policy(struct task_struct * p)231  static inline int task_has_rt_policy(struct task_struct *p)
232  {
233  	return rt_policy(p->policy);
234  }
235  
task_has_dl_policy(struct task_struct * p)236  static inline int task_has_dl_policy(struct task_struct *p)
237  {
238  	return dl_policy(p->policy);
239  }
240  
241  #define cap_scale(v, s)		((v)*(s) >> SCHED_CAPACITY_SHIFT)
242  
update_avg(u64 * avg,u64 sample)243  static inline void update_avg(u64 *avg, u64 sample)
244  {
245  	s64 diff = sample - *avg;
246  
247  	*avg += diff / 8;
248  }
249  
250  /*
251   * Shifting a value by an exponent greater *or equal* to the size of said value
252   * is UB; cap at size-1.
253   */
254  #define shr_bound(val, shift)							\
255  	(val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1))
256  
257  /*
258   * cgroup weight knobs should use the common MIN, DFL and MAX values which are
259   * 1, 100 and 10000 respectively. While it loses a bit of range on both ends, it
260   * maps pretty well onto the shares value used by scheduler and the round-trip
261   * conversions preserve the original value over the entire range.
262   */
sched_weight_from_cgroup(unsigned long cgrp_weight)263  static inline unsigned long sched_weight_from_cgroup(unsigned long cgrp_weight)
264  {
265  	return DIV_ROUND_CLOSEST_ULL(cgrp_weight * 1024, CGROUP_WEIGHT_DFL);
266  }
267  
sched_weight_to_cgroup(unsigned long weight)268  static inline unsigned long sched_weight_to_cgroup(unsigned long weight)
269  {
270  	return clamp_t(unsigned long,
271  		       DIV_ROUND_CLOSEST_ULL(weight * CGROUP_WEIGHT_DFL, 1024),
272  		       CGROUP_WEIGHT_MIN, CGROUP_WEIGHT_MAX);
273  }
274  
275  /*
276   * !! For sched_setattr_nocheck() (kernel) only !!
277   *
278   * This is actually gross. :(
279   *
280   * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
281   * tasks, but still be able to sleep. We need this on platforms that cannot
282   * atomically change clock frequency. Remove once fast switching will be
283   * available on such platforms.
284   *
285   * SUGOV stands for SchedUtil GOVernor.
286   */
287  #define SCHED_FLAG_SUGOV	0x10000000
288  
289  #define SCHED_DL_FLAGS		(SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV)
290  
dl_entity_is_special(const struct sched_dl_entity * dl_se)291  static inline bool dl_entity_is_special(const struct sched_dl_entity *dl_se)
292  {
293  #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
294  	return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
295  #else
296  	return false;
297  #endif
298  }
299  
300  /*
301   * Tells if entity @a should preempt entity @b.
302   */
dl_entity_preempt(const struct sched_dl_entity * a,const struct sched_dl_entity * b)303  static inline bool dl_entity_preempt(const struct sched_dl_entity *a,
304  				     const struct sched_dl_entity *b)
305  {
306  	return dl_entity_is_special(a) ||
307  	       dl_time_before(a->deadline, b->deadline);
308  }
309  
310  /*
311   * This is the priority-queue data structure of the RT scheduling class:
312   */
313  struct rt_prio_array {
314  	DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
315  	struct list_head queue[MAX_RT_PRIO];
316  };
317  
318  struct rt_bandwidth {
319  	/* nests inside the rq lock: */
320  	raw_spinlock_t		rt_runtime_lock;
321  	ktime_t			rt_period;
322  	u64			rt_runtime;
323  	struct hrtimer		rt_period_timer;
324  	unsigned int		rt_period_active;
325  };
326  
dl_bandwidth_enabled(void)327  static inline int dl_bandwidth_enabled(void)
328  {
329  	return sysctl_sched_rt_runtime >= 0;
330  }
331  
332  /*
333   * To keep the bandwidth of -deadline tasks under control
334   * we need some place where:
335   *  - store the maximum -deadline bandwidth of each cpu;
336   *  - cache the fraction of bandwidth that is currently allocated in
337   *    each root domain;
338   *
339   * This is all done in the data structure below. It is similar to the
340   * one used for RT-throttling (rt_bandwidth), with the main difference
341   * that, since here we are only interested in admission control, we
342   * do not decrease any runtime while the group "executes", neither we
343   * need a timer to replenish it.
344   *
345   * With respect to SMP, bandwidth is given on a per root domain basis,
346   * meaning that:
347   *  - bw (< 100%) is the deadline bandwidth of each CPU;
348   *  - total_bw is the currently allocated bandwidth in each root domain;
349   */
350  struct dl_bw {
351  	raw_spinlock_t		lock;
352  	u64			bw;
353  	u64			total_bw;
354  };
355  
356  extern void init_dl_bw(struct dl_bw *dl_b);
357  extern int  sched_dl_global_validate(void);
358  extern void sched_dl_do_global(void);
359  extern int  sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
360  extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
361  extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
362  extern bool __checkparam_dl(const struct sched_attr *attr);
363  extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
364  extern int  dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
365  extern int  dl_bw_check_overflow(int cpu);
366  extern s64 dl_scaled_delta_exec(struct rq *rq, struct sched_dl_entity *dl_se, s64 delta_exec);
367  /*
368   * SCHED_DEADLINE supports servers (nested scheduling) with the following
369   * interface:
370   *
371   *   dl_se::rq -- runqueue we belong to.
372   *
373   *   dl_se::server_has_tasks() -- used on bandwidth enforcement; we 'stop' the
374   *                                server when it runs out of tasks to run.
375   *
376   *   dl_se::server_pick() -- nested pick_next_task(); we yield the period if this
377   *                           returns NULL.
378   *
379   *   dl_server_update() -- called from update_curr_common(), propagates runtime
380   *                         to the server.
381   *
382   *   dl_server_start()
383   *   dl_server_stop()  -- start/stop the server when it has (no) tasks.
384   *
385   *   dl_server_init() -- initializes the server.
386   */
387  extern void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec);
388  extern void dl_server_start(struct sched_dl_entity *dl_se);
389  extern void dl_server_stop(struct sched_dl_entity *dl_se);
390  extern void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq,
391  		    dl_server_has_tasks_f has_tasks,
392  		    dl_server_pick_f pick_task);
393  
394  extern void dl_server_update_idle_time(struct rq *rq,
395  		    struct task_struct *p);
396  extern void fair_server_init(struct rq *rq);
397  extern void __dl_server_attach_root(struct sched_dl_entity *dl_se, struct rq *rq);
398  extern int dl_server_apply_params(struct sched_dl_entity *dl_se,
399  		    u64 runtime, u64 period, bool init);
400  
401  #ifdef CONFIG_CGROUP_SCHED
402  
403  extern struct list_head task_groups;
404  
405  struct cfs_bandwidth {
406  #ifdef CONFIG_CFS_BANDWIDTH
407  	raw_spinlock_t		lock;
408  	ktime_t			period;
409  	u64			quota;
410  	u64			runtime;
411  	u64			burst;
412  	u64			runtime_snap;
413  	s64			hierarchical_quota;
414  
415  	u8			idle;
416  	u8			period_active;
417  	u8			slack_started;
418  	struct hrtimer		period_timer;
419  	struct hrtimer		slack_timer;
420  	struct list_head	throttled_cfs_rq;
421  
422  	/* Statistics: */
423  	int			nr_periods;
424  	int			nr_throttled;
425  	int			nr_burst;
426  	u64			throttled_time;
427  	u64			burst_time;
428  #endif
429  };
430  
431  /* Task group related information */
432  struct task_group {
433  	struct cgroup_subsys_state css;
434  
435  #ifdef CONFIG_GROUP_SCHED_WEIGHT
436  	/* A positive value indicates that this is a SCHED_IDLE group. */
437  	int			idle;
438  #endif
439  
440  #ifdef CONFIG_FAIR_GROUP_SCHED
441  	/* schedulable entities of this group on each CPU */
442  	struct sched_entity	**se;
443  	/* runqueue "owned" by this group on each CPU */
444  	struct cfs_rq		**cfs_rq;
445  	unsigned long		shares;
446  #ifdef	CONFIG_SMP
447  	/*
448  	 * load_avg can be heavily contended at clock tick time, so put
449  	 * it in its own cache-line separated from the fields above which
450  	 * will also be accessed at each tick.
451  	 */
452  	atomic_long_t		load_avg ____cacheline_aligned;
453  #endif
454  #endif
455  
456  #ifdef CONFIG_RT_GROUP_SCHED
457  	struct sched_rt_entity	**rt_se;
458  	struct rt_rq		**rt_rq;
459  
460  	struct rt_bandwidth	rt_bandwidth;
461  #endif
462  
463  #ifdef CONFIG_EXT_GROUP_SCHED
464  	u32			scx_flags;	/* SCX_TG_* */
465  	u32			scx_weight;
466  #endif
467  
468  	struct rcu_head		rcu;
469  	struct list_head	list;
470  
471  	struct task_group	*parent;
472  	struct list_head	siblings;
473  	struct list_head	children;
474  
475  #ifdef CONFIG_SCHED_AUTOGROUP
476  	struct autogroup	*autogroup;
477  #endif
478  
479  	struct cfs_bandwidth	cfs_bandwidth;
480  
481  #ifdef CONFIG_UCLAMP_TASK_GROUP
482  	/* The two decimal precision [%] value requested from user-space */
483  	unsigned int		uclamp_pct[UCLAMP_CNT];
484  	/* Clamp values requested for a task group */
485  	struct uclamp_se	uclamp_req[UCLAMP_CNT];
486  	/* Effective clamp values used for a task group */
487  	struct uclamp_se	uclamp[UCLAMP_CNT];
488  #endif
489  
490  };
491  
492  #ifdef CONFIG_GROUP_SCHED_WEIGHT
493  #define ROOT_TASK_GROUP_LOAD	NICE_0_LOAD
494  
495  /*
496   * A weight of 0 or 1 can cause arithmetics problems.
497   * A weight of a cfs_rq is the sum of weights of which entities
498   * are queued on this cfs_rq, so a weight of a entity should not be
499   * too large, so as the shares value of a task group.
500   * (The default weight is 1024 - so there's no practical
501   *  limitation from this.)
502   */
503  #define MIN_SHARES		(1UL <<  1)
504  #define MAX_SHARES		(1UL << 18)
505  #endif
506  
507  typedef int (*tg_visitor)(struct task_group *, void *);
508  
509  extern int walk_tg_tree_from(struct task_group *from,
510  			     tg_visitor down, tg_visitor up, void *data);
511  
512  /*
513   * Iterate the full tree, calling @down when first entering a node and @up when
514   * leaving it for the final time.
515   *
516   * Caller must hold rcu_lock or sufficient equivalent.
517   */
walk_tg_tree(tg_visitor down,tg_visitor up,void * data)518  static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
519  {
520  	return walk_tg_tree_from(&root_task_group, down, up, data);
521  }
522  
css_tg(struct cgroup_subsys_state * css)523  static inline struct task_group *css_tg(struct cgroup_subsys_state *css)
524  {
525  	return css ? container_of(css, struct task_group, css) : NULL;
526  }
527  
528  extern int tg_nop(struct task_group *tg, void *data);
529  
530  #ifdef CONFIG_FAIR_GROUP_SCHED
531  extern void free_fair_sched_group(struct task_group *tg);
532  extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
533  extern void online_fair_sched_group(struct task_group *tg);
534  extern void unregister_fair_sched_group(struct task_group *tg);
535  #else
free_fair_sched_group(struct task_group * tg)536  static inline void free_fair_sched_group(struct task_group *tg) { }
alloc_fair_sched_group(struct task_group * tg,struct task_group * parent)537  static inline int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
538  {
539         return 1;
540  }
online_fair_sched_group(struct task_group * tg)541  static inline void online_fair_sched_group(struct task_group *tg) { }
unregister_fair_sched_group(struct task_group * tg)542  static inline void unregister_fair_sched_group(struct task_group *tg) { }
543  #endif
544  
545  extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
546  			struct sched_entity *se, int cpu,
547  			struct sched_entity *parent);
548  extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b, struct cfs_bandwidth *parent);
549  
550  extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
551  extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
552  extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
553  extern bool cfs_task_bw_constrained(struct task_struct *p);
554  
555  extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
556  		struct sched_rt_entity *rt_se, int cpu,
557  		struct sched_rt_entity *parent);
558  extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
559  extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
560  extern long sched_group_rt_runtime(struct task_group *tg);
561  extern long sched_group_rt_period(struct task_group *tg);
562  extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
563  
564  extern struct task_group *sched_create_group(struct task_group *parent);
565  extern void sched_online_group(struct task_group *tg,
566  			       struct task_group *parent);
567  extern void sched_destroy_group(struct task_group *tg);
568  extern void sched_release_group(struct task_group *tg);
569  
570  extern void sched_move_task(struct task_struct *tsk);
571  
572  #ifdef CONFIG_FAIR_GROUP_SCHED
573  extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
574  
575  extern int sched_group_set_idle(struct task_group *tg, long idle);
576  
577  #ifdef CONFIG_SMP
578  extern void set_task_rq_fair(struct sched_entity *se,
579  			     struct cfs_rq *prev, struct cfs_rq *next);
580  #else /* !CONFIG_SMP */
set_task_rq_fair(struct sched_entity * se,struct cfs_rq * prev,struct cfs_rq * next)581  static inline void set_task_rq_fair(struct sched_entity *se,
582  			     struct cfs_rq *prev, struct cfs_rq *next) { }
583  #endif /* CONFIG_SMP */
584  #else /* !CONFIG_FAIR_GROUP_SCHED */
sched_group_set_shares(struct task_group * tg,unsigned long shares)585  static inline int sched_group_set_shares(struct task_group *tg, unsigned long shares) { return 0; }
sched_group_set_idle(struct task_group * tg,long idle)586  static inline int sched_group_set_idle(struct task_group *tg, long idle) { return 0; }
587  #endif /* CONFIG_FAIR_GROUP_SCHED */
588  
589  #else /* CONFIG_CGROUP_SCHED */
590  
591  struct cfs_bandwidth { };
592  
cfs_task_bw_constrained(struct task_struct * p)593  static inline bool cfs_task_bw_constrained(struct task_struct *p) { return false; }
594  
595  #endif	/* CONFIG_CGROUP_SCHED */
596  
597  extern void unregister_rt_sched_group(struct task_group *tg);
598  extern void free_rt_sched_group(struct task_group *tg);
599  extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
600  
601  /*
602   * u64_u32_load/u64_u32_store
603   *
604   * Use a copy of a u64 value to protect against data race. This is only
605   * applicable for 32-bits architectures.
606   */
607  #ifdef CONFIG_64BIT
608  # define u64_u32_load_copy(var, copy)		var
609  # define u64_u32_store_copy(var, copy, val)	(var = val)
610  #else
611  # define u64_u32_load_copy(var, copy)					\
612  ({									\
613  	u64 __val, __val_copy;						\
614  	do {								\
615  		__val_copy = copy;					\
616  		/*							\
617  		 * paired with u64_u32_store_copy(), ordering access	\
618  		 * to var and copy.					\
619  		 */							\
620  		smp_rmb();						\
621  		__val = var;						\
622  	} while (__val != __val_copy);					\
623  	__val;								\
624  })
625  # define u64_u32_store_copy(var, copy, val)				\
626  do {									\
627  	typeof(val) __val = (val);					\
628  	var = __val;							\
629  	/*								\
630  	 * paired with u64_u32_load_copy(), ordering access to var and	\
631  	 * copy.							\
632  	 */								\
633  	smp_wmb();							\
634  	copy = __val;							\
635  } while (0)
636  #endif
637  # define u64_u32_load(var)		u64_u32_load_copy(var, var##_copy)
638  # define u64_u32_store(var, val)	u64_u32_store_copy(var, var##_copy, val)
639  
640  struct balance_callback {
641  	struct balance_callback *next;
642  	void (*func)(struct rq *rq);
643  };
644  
645  /* CFS-related fields in a runqueue */
646  struct cfs_rq {
647  	struct load_weight	load;
648  	unsigned int		nr_running;
649  	unsigned int		h_nr_running;      /* SCHED_{NORMAL,BATCH,IDLE} */
650  	unsigned int		idle_nr_running;   /* SCHED_IDLE */
651  	unsigned int		idle_h_nr_running; /* SCHED_IDLE */
652  
653  	s64			avg_vruntime;
654  	u64			avg_load;
655  
656  	u64			min_vruntime;
657  #ifdef CONFIG_SCHED_CORE
658  	unsigned int		forceidle_seq;
659  	u64			min_vruntime_fi;
660  #endif
661  
662  	struct rb_root_cached	tasks_timeline;
663  
664  	/*
665  	 * 'curr' points to currently running entity on this cfs_rq.
666  	 * It is set to NULL otherwise (i.e when none are currently running).
667  	 */
668  	struct sched_entity	*curr;
669  	struct sched_entity	*next;
670  
671  #ifdef CONFIG_SMP
672  	/*
673  	 * CFS load tracking
674  	 */
675  	struct sched_avg	avg;
676  #ifndef CONFIG_64BIT
677  	u64			last_update_time_copy;
678  #endif
679  	struct {
680  		raw_spinlock_t	lock ____cacheline_aligned;
681  		int		nr;
682  		unsigned long	load_avg;
683  		unsigned long	util_avg;
684  		unsigned long	runnable_avg;
685  	} removed;
686  
687  #ifdef CONFIG_FAIR_GROUP_SCHED
688  	u64			last_update_tg_load_avg;
689  	unsigned long		tg_load_avg_contrib;
690  	long			propagate;
691  	long			prop_runnable_sum;
692  
693  	/*
694  	 *   h_load = weight * f(tg)
695  	 *
696  	 * Where f(tg) is the recursive weight fraction assigned to
697  	 * this group.
698  	 */
699  	unsigned long		h_load;
700  	u64			last_h_load_update;
701  	struct sched_entity	*h_load_next;
702  #endif /* CONFIG_FAIR_GROUP_SCHED */
703  #endif /* CONFIG_SMP */
704  
705  #ifdef CONFIG_FAIR_GROUP_SCHED
706  	struct rq		*rq;	/* CPU runqueue to which this cfs_rq is attached */
707  
708  	/*
709  	 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
710  	 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
711  	 * (like users, containers etc.)
712  	 *
713  	 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
714  	 * This list is used during load balance.
715  	 */
716  	int			on_list;
717  	struct list_head	leaf_cfs_rq_list;
718  	struct task_group	*tg;	/* group that "owns" this runqueue */
719  
720  	/* Locally cached copy of our task_group's idle value */
721  	int			idle;
722  
723  #ifdef CONFIG_CFS_BANDWIDTH
724  	int			runtime_enabled;
725  	s64			runtime_remaining;
726  
727  	u64			throttled_pelt_idle;
728  #ifndef CONFIG_64BIT
729  	u64                     throttled_pelt_idle_copy;
730  #endif
731  	u64			throttled_clock;
732  	u64			throttled_clock_pelt;
733  	u64			throttled_clock_pelt_time;
734  	u64			throttled_clock_self;
735  	u64			throttled_clock_self_time;
736  	int			throttled;
737  	int			throttle_count;
738  	struct list_head	throttled_list;
739  	struct list_head	throttled_csd_list;
740  #endif /* CONFIG_CFS_BANDWIDTH */
741  #endif /* CONFIG_FAIR_GROUP_SCHED */
742  };
743  
744  #ifdef CONFIG_SCHED_CLASS_EXT
745  /* scx_rq->flags, protected by the rq lock */
746  enum scx_rq_flags {
747  	/*
748  	 * A hotplugged CPU starts scheduling before rq_online_scx(). Track
749  	 * ops.cpu_on/offline() state so that ops.enqueue/dispatch() are called
750  	 * only while the BPF scheduler considers the CPU to be online.
751  	 */
752  	SCX_RQ_ONLINE		= 1 << 0,
753  	SCX_RQ_CAN_STOP_TICK	= 1 << 1,
754  	SCX_RQ_BAL_PENDING	= 1 << 2, /* balance hasn't run yet */
755  	SCX_RQ_BAL_KEEP		= 1 << 3, /* balance decided to keep current */
756  	SCX_RQ_BYPASSING	= 1 << 4,
757  
758  	SCX_RQ_IN_WAKEUP	= 1 << 16,
759  	SCX_RQ_IN_BALANCE	= 1 << 17,
760  };
761  
762  struct scx_rq {
763  	struct scx_dispatch_q	local_dsq;
764  	struct list_head	runnable_list;		/* runnable tasks on this rq */
765  	struct list_head	ddsp_deferred_locals;	/* deferred ddsps from enq */
766  	unsigned long		ops_qseq;
767  	u64			extra_enq_flags;	/* see move_task_to_local_dsq() */
768  	u32			nr_running;
769  	u32			flags;
770  	u32			cpuperf_target;		/* [0, SCHED_CAPACITY_SCALE] */
771  	bool			cpu_released;
772  	cpumask_var_t		cpus_to_kick;
773  	cpumask_var_t		cpus_to_kick_if_idle;
774  	cpumask_var_t		cpus_to_preempt;
775  	cpumask_var_t		cpus_to_wait;
776  	unsigned long		pnt_seq;
777  	struct balance_callback	deferred_bal_cb;
778  	struct irq_work		deferred_irq_work;
779  	struct irq_work		kick_cpus_irq_work;
780  };
781  #endif /* CONFIG_SCHED_CLASS_EXT */
782  
rt_bandwidth_enabled(void)783  static inline int rt_bandwidth_enabled(void)
784  {
785  	return sysctl_sched_rt_runtime >= 0;
786  }
787  
788  /* RT IPI pull logic requires IRQ_WORK */
789  #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
790  # define HAVE_RT_PUSH_IPI
791  #endif
792  
793  /* Real-Time classes' related field in a runqueue: */
794  struct rt_rq {
795  	struct rt_prio_array	active;
796  	unsigned int		rt_nr_running;
797  	unsigned int		rr_nr_running;
798  #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
799  	struct {
800  		int		curr; /* highest queued rt task prio */
801  #ifdef CONFIG_SMP
802  		int		next; /* next highest */
803  #endif
804  	} highest_prio;
805  #endif
806  #ifdef CONFIG_SMP
807  	bool			overloaded;
808  	struct plist_head	pushable_tasks;
809  
810  #endif /* CONFIG_SMP */
811  	int			rt_queued;
812  
813  #ifdef CONFIG_RT_GROUP_SCHED
814  	int			rt_throttled;
815  	u64			rt_time;
816  	u64			rt_runtime;
817  	/* Nests inside the rq lock: */
818  	raw_spinlock_t		rt_runtime_lock;
819  
820  	unsigned int		rt_nr_boosted;
821  
822  	struct rq		*rq;
823  	struct task_group	*tg;
824  #endif
825  };
826  
rt_rq_is_runnable(struct rt_rq * rt_rq)827  static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
828  {
829  	return rt_rq->rt_queued && rt_rq->rt_nr_running;
830  }
831  
832  /* Deadline class' related fields in a runqueue */
833  struct dl_rq {
834  	/* runqueue is an rbtree, ordered by deadline */
835  	struct rb_root_cached	root;
836  
837  	unsigned int		dl_nr_running;
838  
839  #ifdef CONFIG_SMP
840  	/*
841  	 * Deadline values of the currently executing and the
842  	 * earliest ready task on this rq. Caching these facilitates
843  	 * the decision whether or not a ready but not running task
844  	 * should migrate somewhere else.
845  	 */
846  	struct {
847  		u64		curr;
848  		u64		next;
849  	} earliest_dl;
850  
851  	bool			overloaded;
852  
853  	/*
854  	 * Tasks on this rq that can be pushed away. They are kept in
855  	 * an rb-tree, ordered by tasks' deadlines, with caching
856  	 * of the leftmost (earliest deadline) element.
857  	 */
858  	struct rb_root_cached	pushable_dl_tasks_root;
859  #else
860  	struct dl_bw		dl_bw;
861  #endif
862  	/*
863  	 * "Active utilization" for this runqueue: increased when a
864  	 * task wakes up (becomes TASK_RUNNING) and decreased when a
865  	 * task blocks
866  	 */
867  	u64			running_bw;
868  
869  	/*
870  	 * Utilization of the tasks "assigned" to this runqueue (including
871  	 * the tasks that are in runqueue and the tasks that executed on this
872  	 * CPU and blocked). Increased when a task moves to this runqueue, and
873  	 * decreased when the task moves away (migrates, changes scheduling
874  	 * policy, or terminates).
875  	 * This is needed to compute the "inactive utilization" for the
876  	 * runqueue (inactive utilization = this_bw - running_bw).
877  	 */
878  	u64			this_bw;
879  	u64			extra_bw;
880  
881  	/*
882  	 * Maximum available bandwidth for reclaiming by SCHED_FLAG_RECLAIM
883  	 * tasks of this rq. Used in calculation of reclaimable bandwidth(GRUB).
884  	 */
885  	u64			max_bw;
886  
887  	/*
888  	 * Inverse of the fraction of CPU utilization that can be reclaimed
889  	 * by the GRUB algorithm.
890  	 */
891  	u64			bw_ratio;
892  };
893  
894  #ifdef CONFIG_FAIR_GROUP_SCHED
895  
896  /* An entity is a task if it doesn't "own" a runqueue */
897  #define entity_is_task(se)	(!se->my_q)
898  
se_update_runnable(struct sched_entity * se)899  static inline void se_update_runnable(struct sched_entity *se)
900  {
901  	if (!entity_is_task(se))
902  		se->runnable_weight = se->my_q->h_nr_running;
903  }
904  
se_runnable(struct sched_entity * se)905  static inline long se_runnable(struct sched_entity *se)
906  {
907  	if (se->sched_delayed)
908  		return false;
909  
910  	if (entity_is_task(se))
911  		return !!se->on_rq;
912  	else
913  		return se->runnable_weight;
914  }
915  
916  #else /* !CONFIG_FAIR_GROUP_SCHED: */
917  
918  #define entity_is_task(se)	1
919  
se_update_runnable(struct sched_entity * se)920  static inline void se_update_runnable(struct sched_entity *se) { }
921  
se_runnable(struct sched_entity * se)922  static inline long se_runnable(struct sched_entity *se)
923  {
924  	if (se->sched_delayed)
925  		return false;
926  
927  	return !!se->on_rq;
928  }
929  
930  #endif /* !CONFIG_FAIR_GROUP_SCHED */
931  
932  #ifdef CONFIG_SMP
933  /*
934   * XXX we want to get rid of these helpers and use the full load resolution.
935   */
se_weight(struct sched_entity * se)936  static inline long se_weight(struct sched_entity *se)
937  {
938  	return scale_load_down(se->load.weight);
939  }
940  
941  
sched_asym_prefer(int a,int b)942  static inline bool sched_asym_prefer(int a, int b)
943  {
944  	return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
945  }
946  
947  struct perf_domain {
948  	struct em_perf_domain *em_pd;
949  	struct perf_domain *next;
950  	struct rcu_head rcu;
951  };
952  
953  /*
954   * We add the notion of a root-domain which will be used to define per-domain
955   * variables. Each exclusive cpuset essentially defines an island domain by
956   * fully partitioning the member CPUs from any other cpuset. Whenever a new
957   * exclusive cpuset is created, we also create and attach a new root-domain
958   * object.
959   *
960   */
961  struct root_domain {
962  	atomic_t		refcount;
963  	atomic_t		rto_count;
964  	struct rcu_head		rcu;
965  	cpumask_var_t		span;
966  	cpumask_var_t		online;
967  
968  	/*
969  	 * Indicate pullable load on at least one CPU, e.g:
970  	 * - More than one runnable task
971  	 * - Running task is misfit
972  	 */
973  	bool			overloaded;
974  
975  	/* Indicate one or more CPUs over-utilized (tipping point) */
976  	bool			overutilized;
977  
978  	/*
979  	 * The bit corresponding to a CPU gets set here if such CPU has more
980  	 * than one runnable -deadline task (as it is below for RT tasks).
981  	 */
982  	cpumask_var_t		dlo_mask;
983  	atomic_t		dlo_count;
984  	struct dl_bw		dl_bw;
985  	struct cpudl		cpudl;
986  
987  	/*
988  	 * Indicate whether a root_domain's dl_bw has been checked or
989  	 * updated. It's monotonously increasing value.
990  	 *
991  	 * Also, some corner cases, like 'wrap around' is dangerous, but given
992  	 * that u64 is 'big enough'. So that shouldn't be a concern.
993  	 */
994  	u64 visit_gen;
995  
996  #ifdef HAVE_RT_PUSH_IPI
997  	/*
998  	 * For IPI pull requests, loop across the rto_mask.
999  	 */
1000  	struct irq_work		rto_push_work;
1001  	raw_spinlock_t		rto_lock;
1002  	/* These are only updated and read within rto_lock */
1003  	int			rto_loop;
1004  	int			rto_cpu;
1005  	/* These atomics are updated outside of a lock */
1006  	atomic_t		rto_loop_next;
1007  	atomic_t		rto_loop_start;
1008  #endif
1009  	/*
1010  	 * The "RT overload" flag: it gets set if a CPU has more than
1011  	 * one runnable RT task.
1012  	 */
1013  	cpumask_var_t		rto_mask;
1014  	struct cpupri		cpupri;
1015  
1016  	/*
1017  	 * NULL-terminated list of performance domains intersecting with the
1018  	 * CPUs of the rd. Protected by RCU.
1019  	 */
1020  	struct perf_domain __rcu *pd;
1021  };
1022  
1023  extern void init_defrootdomain(void);
1024  extern int sched_init_domains(const struct cpumask *cpu_map);
1025  extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
1026  extern void sched_get_rd(struct root_domain *rd);
1027  extern void sched_put_rd(struct root_domain *rd);
1028  
get_rd_overloaded(struct root_domain * rd)1029  static inline int get_rd_overloaded(struct root_domain *rd)
1030  {
1031  	return READ_ONCE(rd->overloaded);
1032  }
1033  
set_rd_overloaded(struct root_domain * rd,int status)1034  static inline void set_rd_overloaded(struct root_domain *rd, int status)
1035  {
1036  	if (get_rd_overloaded(rd) != status)
1037  		WRITE_ONCE(rd->overloaded, status);
1038  }
1039  
1040  #ifdef HAVE_RT_PUSH_IPI
1041  extern void rto_push_irq_work_func(struct irq_work *work);
1042  #endif
1043  #endif /* CONFIG_SMP */
1044  
1045  #ifdef CONFIG_UCLAMP_TASK
1046  /*
1047   * struct uclamp_bucket - Utilization clamp bucket
1048   * @value: utilization clamp value for tasks on this clamp bucket
1049   * @tasks: number of RUNNABLE tasks on this clamp bucket
1050   *
1051   * Keep track of how many tasks are RUNNABLE for a given utilization
1052   * clamp value.
1053   */
1054  struct uclamp_bucket {
1055  	unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
1056  	unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
1057  };
1058  
1059  /*
1060   * struct uclamp_rq - rq's utilization clamp
1061   * @value: currently active clamp values for a rq
1062   * @bucket: utilization clamp buckets affecting a rq
1063   *
1064   * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
1065   * A clamp value is affecting a rq when there is at least one task RUNNABLE
1066   * (or actually running) with that value.
1067   *
1068   * There are up to UCLAMP_CNT possible different clamp values, currently there
1069   * are only two: minimum utilization and maximum utilization.
1070   *
1071   * All utilization clamping values are MAX aggregated, since:
1072   * - for util_min: we want to run the CPU at least at the max of the minimum
1073   *   utilization required by its currently RUNNABLE tasks.
1074   * - for util_max: we want to allow the CPU to run up to the max of the
1075   *   maximum utilization allowed by its currently RUNNABLE tasks.
1076   *
1077   * Since on each system we expect only a limited number of different
1078   * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
1079   * the metrics required to compute all the per-rq utilization clamp values.
1080   */
1081  struct uclamp_rq {
1082  	unsigned int value;
1083  	struct uclamp_bucket bucket[UCLAMP_BUCKETS];
1084  };
1085  
1086  DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
1087  #endif /* CONFIG_UCLAMP_TASK */
1088  
1089  /*
1090   * This is the main, per-CPU runqueue data structure.
1091   *
1092   * Locking rule: those places that want to lock multiple runqueues
1093   * (such as the load balancing or the thread migration code), lock
1094   * acquire operations must be ordered by ascending &runqueue.
1095   */
1096  struct rq {
1097  	/* runqueue lock: */
1098  	raw_spinlock_t		__lock;
1099  
1100  	unsigned int		nr_running;
1101  #ifdef CONFIG_NUMA_BALANCING
1102  	unsigned int		nr_numa_running;
1103  	unsigned int		nr_preferred_running;
1104  	unsigned int		numa_migrate_on;
1105  #endif
1106  #ifdef CONFIG_NO_HZ_COMMON
1107  #ifdef CONFIG_SMP
1108  	unsigned long		last_blocked_load_update_tick;
1109  	unsigned int		has_blocked_load;
1110  	call_single_data_t	nohz_csd;
1111  #endif /* CONFIG_SMP */
1112  	unsigned int		nohz_tick_stopped;
1113  	atomic_t		nohz_flags;
1114  #endif /* CONFIG_NO_HZ_COMMON */
1115  
1116  #ifdef CONFIG_SMP
1117  	unsigned int		ttwu_pending;
1118  #endif
1119  	u64			nr_switches;
1120  
1121  #ifdef CONFIG_UCLAMP_TASK
1122  	/* Utilization clamp values based on CPU's RUNNABLE tasks */
1123  	struct uclamp_rq	uclamp[UCLAMP_CNT] ____cacheline_aligned;
1124  	unsigned int		uclamp_flags;
1125  #define UCLAMP_FLAG_IDLE 0x01
1126  #endif
1127  
1128  	struct cfs_rq		cfs;
1129  	struct rt_rq		rt;
1130  	struct dl_rq		dl;
1131  #ifdef CONFIG_SCHED_CLASS_EXT
1132  	struct scx_rq		scx;
1133  #endif
1134  
1135  	struct sched_dl_entity	fair_server;
1136  
1137  #ifdef CONFIG_FAIR_GROUP_SCHED
1138  	/* list of leaf cfs_rq on this CPU: */
1139  	struct list_head	leaf_cfs_rq_list;
1140  	struct list_head	*tmp_alone_branch;
1141  #endif /* CONFIG_FAIR_GROUP_SCHED */
1142  
1143  	/*
1144  	 * This is part of a global counter where only the total sum
1145  	 * over all CPUs matters. A task can increase this counter on
1146  	 * one CPU and if it got migrated afterwards it may decrease
1147  	 * it on another CPU. Always updated under the runqueue lock:
1148  	 */
1149  	unsigned int		nr_uninterruptible;
1150  
1151  	struct task_struct __rcu	*curr;
1152  	struct sched_dl_entity	*dl_server;
1153  	struct task_struct	*idle;
1154  	struct task_struct	*stop;
1155  	unsigned long		next_balance;
1156  	struct mm_struct	*prev_mm;
1157  
1158  	unsigned int		clock_update_flags;
1159  	u64			clock;
1160  	/* Ensure that all clocks are in the same cache line */
1161  	u64			clock_task ____cacheline_aligned;
1162  	u64			clock_pelt;
1163  	unsigned long		lost_idle_time;
1164  	u64			clock_pelt_idle;
1165  	u64			clock_idle;
1166  #ifndef CONFIG_64BIT
1167  	u64			clock_pelt_idle_copy;
1168  	u64			clock_idle_copy;
1169  #endif
1170  
1171  	atomic_t		nr_iowait;
1172  
1173  #ifdef CONFIG_SCHED_DEBUG
1174  	u64 last_seen_need_resched_ns;
1175  	int ticks_without_resched;
1176  #endif
1177  
1178  #ifdef CONFIG_MEMBARRIER
1179  	int membarrier_state;
1180  #endif
1181  
1182  #ifdef CONFIG_SMP
1183  	struct root_domain		*rd;
1184  	struct sched_domain __rcu	*sd;
1185  
1186  	unsigned long		cpu_capacity;
1187  
1188  	struct balance_callback *balance_callback;
1189  
1190  	unsigned char		nohz_idle_balance;
1191  	unsigned char		idle_balance;
1192  
1193  	unsigned long		misfit_task_load;
1194  
1195  	/* For active balancing */
1196  	int			active_balance;
1197  	int			push_cpu;
1198  	struct cpu_stop_work	active_balance_work;
1199  
1200  	/* CPU of this runqueue: */
1201  	int			cpu;
1202  	int			online;
1203  
1204  	struct list_head cfs_tasks;
1205  
1206  	struct sched_avg	avg_rt;
1207  	struct sched_avg	avg_dl;
1208  #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1209  	struct sched_avg	avg_irq;
1210  #endif
1211  #ifdef CONFIG_SCHED_HW_PRESSURE
1212  	struct sched_avg	avg_hw;
1213  #endif
1214  	u64			idle_stamp;
1215  	u64			avg_idle;
1216  
1217  	/* This is used to determine avg_idle's max value */
1218  	u64			max_idle_balance_cost;
1219  
1220  #ifdef CONFIG_HOTPLUG_CPU
1221  	struct rcuwait		hotplug_wait;
1222  #endif
1223  #endif /* CONFIG_SMP */
1224  
1225  #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1226  	u64			prev_irq_time;
1227  	u64			psi_irq_time;
1228  #endif
1229  #ifdef CONFIG_PARAVIRT
1230  	u64			prev_steal_time;
1231  #endif
1232  #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1233  	u64			prev_steal_time_rq;
1234  #endif
1235  
1236  	/* calc_load related fields */
1237  	unsigned long		calc_load_update;
1238  	long			calc_load_active;
1239  
1240  #ifdef CONFIG_SCHED_HRTICK
1241  #ifdef CONFIG_SMP
1242  	call_single_data_t	hrtick_csd;
1243  #endif
1244  	struct hrtimer		hrtick_timer;
1245  	ktime_t			hrtick_time;
1246  #endif
1247  
1248  #ifdef CONFIG_SCHEDSTATS
1249  	/* latency stats */
1250  	struct sched_info	rq_sched_info;
1251  	unsigned long long	rq_cpu_time;
1252  
1253  	/* sys_sched_yield() stats */
1254  	unsigned int		yld_count;
1255  
1256  	/* schedule() stats */
1257  	unsigned int		sched_count;
1258  	unsigned int		sched_goidle;
1259  
1260  	/* try_to_wake_up() stats */
1261  	unsigned int		ttwu_count;
1262  	unsigned int		ttwu_local;
1263  #endif
1264  
1265  #ifdef CONFIG_CPU_IDLE
1266  	/* Must be inspected within a RCU lock section */
1267  	struct cpuidle_state	*idle_state;
1268  #endif
1269  
1270  #ifdef CONFIG_SMP
1271  	unsigned int		nr_pinned;
1272  #endif
1273  	unsigned int		push_busy;
1274  	struct cpu_stop_work	push_work;
1275  
1276  #ifdef CONFIG_SCHED_CORE
1277  	/* per rq */
1278  	struct rq		*core;
1279  	struct task_struct	*core_pick;
1280  	struct sched_dl_entity	*core_dl_server;
1281  	unsigned int		core_enabled;
1282  	unsigned int		core_sched_seq;
1283  	struct rb_root		core_tree;
1284  
1285  	/* shared state -- careful with sched_core_cpu_deactivate() */
1286  	unsigned int		core_task_seq;
1287  	unsigned int		core_pick_seq;
1288  	unsigned long		core_cookie;
1289  	unsigned int		core_forceidle_count;
1290  	unsigned int		core_forceidle_seq;
1291  	unsigned int		core_forceidle_occupation;
1292  	u64			core_forceidle_start;
1293  #endif
1294  
1295  	/* Scratch cpumask to be temporarily used under rq_lock */
1296  	cpumask_var_t		scratch_mask;
1297  
1298  #if defined(CONFIG_CFS_BANDWIDTH) && defined(CONFIG_SMP)
1299  	call_single_data_t	cfsb_csd;
1300  	struct list_head	cfsb_csd_list;
1301  #endif
1302  };
1303  
1304  #ifdef CONFIG_FAIR_GROUP_SCHED
1305  
1306  /* CPU runqueue to which this cfs_rq is attached */
rq_of(struct cfs_rq * cfs_rq)1307  static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1308  {
1309  	return cfs_rq->rq;
1310  }
1311  
1312  #else
1313  
rq_of(struct cfs_rq * cfs_rq)1314  static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1315  {
1316  	return container_of(cfs_rq, struct rq, cfs);
1317  }
1318  #endif
1319  
cpu_of(struct rq * rq)1320  static inline int cpu_of(struct rq *rq)
1321  {
1322  #ifdef CONFIG_SMP
1323  	return rq->cpu;
1324  #else
1325  	return 0;
1326  #endif
1327  }
1328  
1329  #define MDF_PUSH		0x01
1330  
is_migration_disabled(struct task_struct * p)1331  static inline bool is_migration_disabled(struct task_struct *p)
1332  {
1333  #ifdef CONFIG_SMP
1334  	return p->migration_disabled;
1335  #else
1336  	return false;
1337  #endif
1338  }
1339  
1340  DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1341  
1342  #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
1343  #define this_rq()		this_cpu_ptr(&runqueues)
1344  #define task_rq(p)		cpu_rq(task_cpu(p))
1345  #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
1346  #define raw_rq()		raw_cpu_ptr(&runqueues)
1347  
1348  #ifdef CONFIG_SCHED_CORE
1349  static inline struct cpumask *sched_group_span(struct sched_group *sg);
1350  
1351  DECLARE_STATIC_KEY_FALSE(__sched_core_enabled);
1352  
sched_core_enabled(struct rq * rq)1353  static inline bool sched_core_enabled(struct rq *rq)
1354  {
1355  	return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled;
1356  }
1357  
sched_core_disabled(void)1358  static inline bool sched_core_disabled(void)
1359  {
1360  	return !static_branch_unlikely(&__sched_core_enabled);
1361  }
1362  
1363  /*
1364   * Be careful with this function; not for general use. The return value isn't
1365   * stable unless you actually hold a relevant rq->__lock.
1366   */
rq_lockp(struct rq * rq)1367  static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1368  {
1369  	if (sched_core_enabled(rq))
1370  		return &rq->core->__lock;
1371  
1372  	return &rq->__lock;
1373  }
1374  
__rq_lockp(struct rq * rq)1375  static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1376  {
1377  	if (rq->core_enabled)
1378  		return &rq->core->__lock;
1379  
1380  	return &rq->__lock;
1381  }
1382  
1383  extern bool
1384  cfs_prio_less(const struct task_struct *a, const struct task_struct *b, bool fi);
1385  
1386  extern void task_vruntime_update(struct rq *rq, struct task_struct *p, bool in_fi);
1387  
1388  /*
1389   * Helpers to check if the CPU's core cookie matches with the task's cookie
1390   * when core scheduling is enabled.
1391   * A special case is that the task's cookie always matches with CPU's core
1392   * cookie if the CPU is in an idle core.
1393   */
sched_cpu_cookie_match(struct rq * rq,struct task_struct * p)1394  static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1395  {
1396  	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1397  	if (!sched_core_enabled(rq))
1398  		return true;
1399  
1400  	return rq->core->core_cookie == p->core_cookie;
1401  }
1402  
sched_core_cookie_match(struct rq * rq,struct task_struct * p)1403  static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1404  {
1405  	bool idle_core = true;
1406  	int cpu;
1407  
1408  	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1409  	if (!sched_core_enabled(rq))
1410  		return true;
1411  
1412  	for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) {
1413  		if (!available_idle_cpu(cpu)) {
1414  			idle_core = false;
1415  			break;
1416  		}
1417  	}
1418  
1419  	/*
1420  	 * A CPU in an idle core is always the best choice for tasks with
1421  	 * cookies.
1422  	 */
1423  	return idle_core || rq->core->core_cookie == p->core_cookie;
1424  }
1425  
sched_group_cookie_match(struct rq * rq,struct task_struct * p,struct sched_group * group)1426  static inline bool sched_group_cookie_match(struct rq *rq,
1427  					    struct task_struct *p,
1428  					    struct sched_group *group)
1429  {
1430  	int cpu;
1431  
1432  	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1433  	if (!sched_core_enabled(rq))
1434  		return true;
1435  
1436  	for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
1437  		if (sched_core_cookie_match(cpu_rq(cpu), p))
1438  			return true;
1439  	}
1440  	return false;
1441  }
1442  
sched_core_enqueued(struct task_struct * p)1443  static inline bool sched_core_enqueued(struct task_struct *p)
1444  {
1445  	return !RB_EMPTY_NODE(&p->core_node);
1446  }
1447  
1448  extern void sched_core_enqueue(struct rq *rq, struct task_struct *p);
1449  extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags);
1450  
1451  extern void sched_core_get(void);
1452  extern void sched_core_put(void);
1453  
1454  #else /* !CONFIG_SCHED_CORE: */
1455  
sched_core_enabled(struct rq * rq)1456  static inline bool sched_core_enabled(struct rq *rq)
1457  {
1458  	return false;
1459  }
1460  
sched_core_disabled(void)1461  static inline bool sched_core_disabled(void)
1462  {
1463  	return true;
1464  }
1465  
rq_lockp(struct rq * rq)1466  static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1467  {
1468  	return &rq->__lock;
1469  }
1470  
__rq_lockp(struct rq * rq)1471  static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1472  {
1473  	return &rq->__lock;
1474  }
1475  
sched_cpu_cookie_match(struct rq * rq,struct task_struct * p)1476  static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1477  {
1478  	return true;
1479  }
1480  
sched_core_cookie_match(struct rq * rq,struct task_struct * p)1481  static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1482  {
1483  	return true;
1484  }
1485  
sched_group_cookie_match(struct rq * rq,struct task_struct * p,struct sched_group * group)1486  static inline bool sched_group_cookie_match(struct rq *rq,
1487  					    struct task_struct *p,
1488  					    struct sched_group *group)
1489  {
1490  	return true;
1491  }
1492  
1493  #endif /* !CONFIG_SCHED_CORE */
1494  
lockdep_assert_rq_held(struct rq * rq)1495  static inline void lockdep_assert_rq_held(struct rq *rq)
1496  {
1497  	lockdep_assert_held(__rq_lockp(rq));
1498  }
1499  
1500  extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass);
1501  extern bool raw_spin_rq_trylock(struct rq *rq);
1502  extern void raw_spin_rq_unlock(struct rq *rq);
1503  
raw_spin_rq_lock(struct rq * rq)1504  static inline void raw_spin_rq_lock(struct rq *rq)
1505  {
1506  	raw_spin_rq_lock_nested(rq, 0);
1507  }
1508  
raw_spin_rq_lock_irq(struct rq * rq)1509  static inline void raw_spin_rq_lock_irq(struct rq *rq)
1510  {
1511  	local_irq_disable();
1512  	raw_spin_rq_lock(rq);
1513  }
1514  
raw_spin_rq_unlock_irq(struct rq * rq)1515  static inline void raw_spin_rq_unlock_irq(struct rq *rq)
1516  {
1517  	raw_spin_rq_unlock(rq);
1518  	local_irq_enable();
1519  }
1520  
_raw_spin_rq_lock_irqsave(struct rq * rq)1521  static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq)
1522  {
1523  	unsigned long flags;
1524  
1525  	local_irq_save(flags);
1526  	raw_spin_rq_lock(rq);
1527  
1528  	return flags;
1529  }
1530  
raw_spin_rq_unlock_irqrestore(struct rq * rq,unsigned long flags)1531  static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags)
1532  {
1533  	raw_spin_rq_unlock(rq);
1534  	local_irq_restore(flags);
1535  }
1536  
1537  #define raw_spin_rq_lock_irqsave(rq, flags)	\
1538  do {						\
1539  	flags = _raw_spin_rq_lock_irqsave(rq);	\
1540  } while (0)
1541  
1542  #ifdef CONFIG_SCHED_SMT
1543  extern void __update_idle_core(struct rq *rq);
1544  
update_idle_core(struct rq * rq)1545  static inline void update_idle_core(struct rq *rq)
1546  {
1547  	if (static_branch_unlikely(&sched_smt_present))
1548  		__update_idle_core(rq);
1549  }
1550  
1551  #else
update_idle_core(struct rq * rq)1552  static inline void update_idle_core(struct rq *rq) { }
1553  #endif
1554  
1555  #ifdef CONFIG_FAIR_GROUP_SCHED
1556  
task_of(struct sched_entity * se)1557  static inline struct task_struct *task_of(struct sched_entity *se)
1558  {
1559  	SCHED_WARN_ON(!entity_is_task(se));
1560  	return container_of(se, struct task_struct, se);
1561  }
1562  
task_cfs_rq(struct task_struct * p)1563  static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1564  {
1565  	return p->se.cfs_rq;
1566  }
1567  
1568  /* runqueue on which this entity is (to be) queued */
cfs_rq_of(const struct sched_entity * se)1569  static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1570  {
1571  	return se->cfs_rq;
1572  }
1573  
1574  /* runqueue "owned" by this group */
group_cfs_rq(struct sched_entity * grp)1575  static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1576  {
1577  	return grp->my_q;
1578  }
1579  
1580  #else /* !CONFIG_FAIR_GROUP_SCHED: */
1581  
1582  #define task_of(_se)		container_of(_se, struct task_struct, se)
1583  
task_cfs_rq(const struct task_struct * p)1584  static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p)
1585  {
1586  	return &task_rq(p)->cfs;
1587  }
1588  
cfs_rq_of(const struct sched_entity * se)1589  static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1590  {
1591  	const struct task_struct *p = task_of(se);
1592  	struct rq *rq = task_rq(p);
1593  
1594  	return &rq->cfs;
1595  }
1596  
1597  /* runqueue "owned" by this group */
group_cfs_rq(struct sched_entity * grp)1598  static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1599  {
1600  	return NULL;
1601  }
1602  
1603  #endif /* !CONFIG_FAIR_GROUP_SCHED */
1604  
1605  extern void update_rq_clock(struct rq *rq);
1606  
1607  /*
1608   * rq::clock_update_flags bits
1609   *
1610   * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1611   *  call to __schedule(). This is an optimisation to avoid
1612   *  neighbouring rq clock updates.
1613   *
1614   * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1615   *  in effect and calls to update_rq_clock() are being ignored.
1616   *
1617   * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1618   *  made to update_rq_clock() since the last time rq::lock was pinned.
1619   *
1620   * If inside of __schedule(), clock_update_flags will have been
1621   * shifted left (a left shift is a cheap operation for the fast path
1622   * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1623   *
1624   *	if (rq-clock_update_flags >= RQCF_UPDATED)
1625   *
1626   * to check if %RQCF_UPDATED is set. It'll never be shifted more than
1627   * one position though, because the next rq_unpin_lock() will shift it
1628   * back.
1629   */
1630  #define RQCF_REQ_SKIP		0x01
1631  #define RQCF_ACT_SKIP		0x02
1632  #define RQCF_UPDATED		0x04
1633  
assert_clock_updated(struct rq * rq)1634  static inline void assert_clock_updated(struct rq *rq)
1635  {
1636  	/*
1637  	 * The only reason for not seeing a clock update since the
1638  	 * last rq_pin_lock() is if we're currently skipping updates.
1639  	 */
1640  	SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
1641  }
1642  
rq_clock(struct rq * rq)1643  static inline u64 rq_clock(struct rq *rq)
1644  {
1645  	lockdep_assert_rq_held(rq);
1646  	assert_clock_updated(rq);
1647  
1648  	return rq->clock;
1649  }
1650  
rq_clock_task(struct rq * rq)1651  static inline u64 rq_clock_task(struct rq *rq)
1652  {
1653  	lockdep_assert_rq_held(rq);
1654  	assert_clock_updated(rq);
1655  
1656  	return rq->clock_task;
1657  }
1658  
rq_clock_skip_update(struct rq * rq)1659  static inline void rq_clock_skip_update(struct rq *rq)
1660  {
1661  	lockdep_assert_rq_held(rq);
1662  	rq->clock_update_flags |= RQCF_REQ_SKIP;
1663  }
1664  
1665  /*
1666   * See rt task throttling, which is the only time a skip
1667   * request is canceled.
1668   */
rq_clock_cancel_skipupdate(struct rq * rq)1669  static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1670  {
1671  	lockdep_assert_rq_held(rq);
1672  	rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1673  }
1674  
1675  /*
1676   * During cpu offlining and rq wide unthrottling, we can trigger
1677   * an update_rq_clock() for several cfs and rt runqueues (Typically
1678   * when using list_for_each_entry_*)
1679   * rq_clock_start_loop_update() can be called after updating the clock
1680   * once and before iterating over the list to prevent multiple update.
1681   * After the iterative traversal, we need to call rq_clock_stop_loop_update()
1682   * to clear RQCF_ACT_SKIP of rq->clock_update_flags.
1683   */
rq_clock_start_loop_update(struct rq * rq)1684  static inline void rq_clock_start_loop_update(struct rq *rq)
1685  {
1686  	lockdep_assert_rq_held(rq);
1687  	SCHED_WARN_ON(rq->clock_update_flags & RQCF_ACT_SKIP);
1688  	rq->clock_update_flags |= RQCF_ACT_SKIP;
1689  }
1690  
rq_clock_stop_loop_update(struct rq * rq)1691  static inline void rq_clock_stop_loop_update(struct rq *rq)
1692  {
1693  	lockdep_assert_rq_held(rq);
1694  	rq->clock_update_flags &= ~RQCF_ACT_SKIP;
1695  }
1696  
1697  struct rq_flags {
1698  	unsigned long flags;
1699  	struct pin_cookie cookie;
1700  #ifdef CONFIG_SCHED_DEBUG
1701  	/*
1702  	 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1703  	 * current pin context is stashed here in case it needs to be
1704  	 * restored in rq_repin_lock().
1705  	 */
1706  	unsigned int clock_update_flags;
1707  #endif
1708  };
1709  
1710  extern struct balance_callback balance_push_callback;
1711  
1712  /*
1713   * Lockdep annotation that avoids accidental unlocks; it's like a
1714   * sticky/continuous lockdep_assert_held().
1715   *
1716   * This avoids code that has access to 'struct rq *rq' (basically everything in
1717   * the scheduler) from accidentally unlocking the rq if they do not also have a
1718   * copy of the (on-stack) 'struct rq_flags rf'.
1719   *
1720   * Also see Documentation/locking/lockdep-design.rst.
1721   */
rq_pin_lock(struct rq * rq,struct rq_flags * rf)1722  static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1723  {
1724  	rf->cookie = lockdep_pin_lock(__rq_lockp(rq));
1725  
1726  #ifdef CONFIG_SCHED_DEBUG
1727  	rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1728  	rf->clock_update_flags = 0;
1729  # ifdef CONFIG_SMP
1730  	SCHED_WARN_ON(rq->balance_callback && rq->balance_callback != &balance_push_callback);
1731  # endif
1732  #endif
1733  }
1734  
rq_unpin_lock(struct rq * rq,struct rq_flags * rf)1735  static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1736  {
1737  #ifdef CONFIG_SCHED_DEBUG
1738  	if (rq->clock_update_flags > RQCF_ACT_SKIP)
1739  		rf->clock_update_flags = RQCF_UPDATED;
1740  #endif
1741  
1742  	lockdep_unpin_lock(__rq_lockp(rq), rf->cookie);
1743  }
1744  
rq_repin_lock(struct rq * rq,struct rq_flags * rf)1745  static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1746  {
1747  	lockdep_repin_lock(__rq_lockp(rq), rf->cookie);
1748  
1749  #ifdef CONFIG_SCHED_DEBUG
1750  	/*
1751  	 * Restore the value we stashed in @rf for this pin context.
1752  	 */
1753  	rq->clock_update_flags |= rf->clock_update_flags;
1754  #endif
1755  }
1756  
1757  extern
1758  struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1759  	__acquires(rq->lock);
1760  
1761  extern
1762  struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1763  	__acquires(p->pi_lock)
1764  	__acquires(rq->lock);
1765  
__task_rq_unlock(struct rq * rq,struct rq_flags * rf)1766  static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1767  	__releases(rq->lock)
1768  {
1769  	rq_unpin_lock(rq, rf);
1770  	raw_spin_rq_unlock(rq);
1771  }
1772  
1773  static inline void
task_rq_unlock(struct rq * rq,struct task_struct * p,struct rq_flags * rf)1774  task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1775  	__releases(rq->lock)
1776  	__releases(p->pi_lock)
1777  {
1778  	rq_unpin_lock(rq, rf);
1779  	raw_spin_rq_unlock(rq);
1780  	raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1781  }
1782  
1783  DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct,
1784  		    _T->rq = task_rq_lock(_T->lock, &_T->rf),
1785  		    task_rq_unlock(_T->rq, _T->lock, &_T->rf),
1786  		    struct rq *rq; struct rq_flags rf)
1787  
rq_lock_irqsave(struct rq * rq,struct rq_flags * rf)1788  static inline void rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1789  	__acquires(rq->lock)
1790  {
1791  	raw_spin_rq_lock_irqsave(rq, rf->flags);
1792  	rq_pin_lock(rq, rf);
1793  }
1794  
rq_lock_irq(struct rq * rq,struct rq_flags * rf)1795  static inline void rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1796  	__acquires(rq->lock)
1797  {
1798  	raw_spin_rq_lock_irq(rq);
1799  	rq_pin_lock(rq, rf);
1800  }
1801  
rq_lock(struct rq * rq,struct rq_flags * rf)1802  static inline void rq_lock(struct rq *rq, struct rq_flags *rf)
1803  	__acquires(rq->lock)
1804  {
1805  	raw_spin_rq_lock(rq);
1806  	rq_pin_lock(rq, rf);
1807  }
1808  
rq_unlock_irqrestore(struct rq * rq,struct rq_flags * rf)1809  static inline void rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1810  	__releases(rq->lock)
1811  {
1812  	rq_unpin_lock(rq, rf);
1813  	raw_spin_rq_unlock_irqrestore(rq, rf->flags);
1814  }
1815  
rq_unlock_irq(struct rq * rq,struct rq_flags * rf)1816  static inline void rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1817  	__releases(rq->lock)
1818  {
1819  	rq_unpin_lock(rq, rf);
1820  	raw_spin_rq_unlock_irq(rq);
1821  }
1822  
rq_unlock(struct rq * rq,struct rq_flags * rf)1823  static inline void rq_unlock(struct rq *rq, struct rq_flags *rf)
1824  	__releases(rq->lock)
1825  {
1826  	rq_unpin_lock(rq, rf);
1827  	raw_spin_rq_unlock(rq);
1828  }
1829  
1830  DEFINE_LOCK_GUARD_1(rq_lock, struct rq,
1831  		    rq_lock(_T->lock, &_T->rf),
1832  		    rq_unlock(_T->lock, &_T->rf),
1833  		    struct rq_flags rf)
1834  
1835  DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq,
1836  		    rq_lock_irq(_T->lock, &_T->rf),
1837  		    rq_unlock_irq(_T->lock, &_T->rf),
1838  		    struct rq_flags rf)
1839  
1840  DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq,
1841  		    rq_lock_irqsave(_T->lock, &_T->rf),
1842  		    rq_unlock_irqrestore(_T->lock, &_T->rf),
1843  		    struct rq_flags rf)
1844  
this_rq_lock_irq(struct rq_flags * rf)1845  static inline struct rq *this_rq_lock_irq(struct rq_flags *rf)
1846  	__acquires(rq->lock)
1847  {
1848  	struct rq *rq;
1849  
1850  	local_irq_disable();
1851  	rq = this_rq();
1852  	rq_lock(rq, rf);
1853  
1854  	return rq;
1855  }
1856  
1857  #ifdef CONFIG_NUMA
1858  
1859  enum numa_topology_type {
1860  	NUMA_DIRECT,
1861  	NUMA_GLUELESS_MESH,
1862  	NUMA_BACKPLANE,
1863  };
1864  
1865  extern enum numa_topology_type sched_numa_topology_type;
1866  extern int sched_max_numa_distance;
1867  extern bool find_numa_distance(int distance);
1868  extern void sched_init_numa(int offline_node);
1869  extern void sched_update_numa(int cpu, bool online);
1870  extern void sched_domains_numa_masks_set(unsigned int cpu);
1871  extern void sched_domains_numa_masks_clear(unsigned int cpu);
1872  extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1873  
1874  #else /* !CONFIG_NUMA: */
1875  
sched_init_numa(int offline_node)1876  static inline void sched_init_numa(int offline_node) { }
sched_update_numa(int cpu,bool online)1877  static inline void sched_update_numa(int cpu, bool online) { }
sched_domains_numa_masks_set(unsigned int cpu)1878  static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
sched_domains_numa_masks_clear(unsigned int cpu)1879  static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1880  
sched_numa_find_closest(const struct cpumask * cpus,int cpu)1881  static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1882  {
1883  	return nr_cpu_ids;
1884  }
1885  
1886  #endif /* !CONFIG_NUMA */
1887  
1888  #ifdef CONFIG_NUMA_BALANCING
1889  
1890  /* The regions in numa_faults array from task_struct */
1891  enum numa_faults_stats {
1892  	NUMA_MEM = 0,
1893  	NUMA_CPU,
1894  	NUMA_MEMBUF,
1895  	NUMA_CPUBUF
1896  };
1897  
1898  extern void sched_setnuma(struct task_struct *p, int node);
1899  extern int migrate_task_to(struct task_struct *p, int cpu);
1900  extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1901  			int cpu, int scpu);
1902  extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1903  
1904  #else /* !CONFIG_NUMA_BALANCING: */
1905  
1906  static inline void
init_numa_balancing(unsigned long clone_flags,struct task_struct * p)1907  init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1908  {
1909  }
1910  
1911  #endif /* !CONFIG_NUMA_BALANCING */
1912  
1913  #ifdef CONFIG_SMP
1914  
1915  static inline void
queue_balance_callback(struct rq * rq,struct balance_callback * head,void (* func)(struct rq * rq))1916  queue_balance_callback(struct rq *rq,
1917  		       struct balance_callback *head,
1918  		       void (*func)(struct rq *rq))
1919  {
1920  	lockdep_assert_rq_held(rq);
1921  
1922  	/*
1923  	 * Don't (re)queue an already queued item; nor queue anything when
1924  	 * balance_push() is active, see the comment with
1925  	 * balance_push_callback.
1926  	 */
1927  	if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
1928  		return;
1929  
1930  	head->func = func;
1931  	head->next = rq->balance_callback;
1932  	rq->balance_callback = head;
1933  }
1934  
1935  #define rcu_dereference_check_sched_domain(p) \
1936  	rcu_dereference_check((p), lockdep_is_held(&sched_domains_mutex))
1937  
1938  /*
1939   * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1940   * See destroy_sched_domains: call_rcu for details.
1941   *
1942   * The domain tree of any CPU may only be accessed from within
1943   * preempt-disabled sections.
1944   */
1945  #define for_each_domain(cpu, __sd) \
1946  	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1947  			__sd; __sd = __sd->parent)
1948  
1949  /* A mask of all the SD flags that have the SDF_SHARED_CHILD metaflag */
1950  #define SD_FLAG(name, mflags) (name * !!((mflags) & SDF_SHARED_CHILD)) |
1951  static const unsigned int SD_SHARED_CHILD_MASK =
1952  #include <linux/sched/sd_flags.h>
1953  0;
1954  #undef SD_FLAG
1955  
1956  /**
1957   * highest_flag_domain - Return highest sched_domain containing flag.
1958   * @cpu:	The CPU whose highest level of sched domain is to
1959   *		be returned.
1960   * @flag:	The flag to check for the highest sched_domain
1961   *		for the given CPU.
1962   *
1963   * Returns the highest sched_domain of a CPU which contains @flag. If @flag has
1964   * the SDF_SHARED_CHILD metaflag, all the children domains also have @flag.
1965   */
highest_flag_domain(int cpu,int flag)1966  static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1967  {
1968  	struct sched_domain *sd, *hsd = NULL;
1969  
1970  	for_each_domain(cpu, sd) {
1971  		if (sd->flags & flag) {
1972  			hsd = sd;
1973  			continue;
1974  		}
1975  
1976  		/*
1977  		 * Stop the search if @flag is known to be shared at lower
1978  		 * levels. It will not be found further up.
1979  		 */
1980  		if (flag & SD_SHARED_CHILD_MASK)
1981  			break;
1982  	}
1983  
1984  	return hsd;
1985  }
1986  
lowest_flag_domain(int cpu,int flag)1987  static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1988  {
1989  	struct sched_domain *sd;
1990  
1991  	for_each_domain(cpu, sd) {
1992  		if (sd->flags & flag)
1993  			break;
1994  	}
1995  
1996  	return sd;
1997  }
1998  
1999  DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
2000  DECLARE_PER_CPU(int, sd_llc_size);
2001  DECLARE_PER_CPU(int, sd_llc_id);
2002  DECLARE_PER_CPU(int, sd_share_id);
2003  DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
2004  DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
2005  DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
2006  DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
2007  
2008  extern struct static_key_false sched_asym_cpucapacity;
2009  extern struct static_key_false sched_cluster_active;
2010  
sched_asym_cpucap_active(void)2011  static __always_inline bool sched_asym_cpucap_active(void)
2012  {
2013  	return static_branch_unlikely(&sched_asym_cpucapacity);
2014  }
2015  
2016  struct sched_group_capacity {
2017  	atomic_t		ref;
2018  	/*
2019  	 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
2020  	 * for a single CPU.
2021  	 */
2022  	unsigned long		capacity;
2023  	unsigned long		min_capacity;		/* Min per-CPU capacity in group */
2024  	unsigned long		max_capacity;		/* Max per-CPU capacity in group */
2025  	unsigned long		next_update;
2026  	int			imbalance;		/* XXX unrelated to capacity but shared group state */
2027  
2028  #ifdef CONFIG_SCHED_DEBUG
2029  	int			id;
2030  #endif
2031  
2032  	unsigned long		cpumask[];		/* Balance mask */
2033  };
2034  
2035  struct sched_group {
2036  	struct sched_group	*next;			/* Must be a circular list */
2037  	atomic_t		ref;
2038  
2039  	unsigned int		group_weight;
2040  	unsigned int		cores;
2041  	struct sched_group_capacity *sgc;
2042  	int			asym_prefer_cpu;	/* CPU of highest priority in group */
2043  	int			flags;
2044  
2045  	/*
2046  	 * The CPUs this group covers.
2047  	 *
2048  	 * NOTE: this field is variable length. (Allocated dynamically
2049  	 * by attaching extra space to the end of the structure,
2050  	 * depending on how many CPUs the kernel has booted up with)
2051  	 */
2052  	unsigned long		cpumask[];
2053  };
2054  
sched_group_span(struct sched_group * sg)2055  static inline struct cpumask *sched_group_span(struct sched_group *sg)
2056  {
2057  	return to_cpumask(sg->cpumask);
2058  }
2059  
2060  /*
2061   * See build_balance_mask().
2062   */
group_balance_mask(struct sched_group * sg)2063  static inline struct cpumask *group_balance_mask(struct sched_group *sg)
2064  {
2065  	return to_cpumask(sg->sgc->cpumask);
2066  }
2067  
2068  extern int group_balance_cpu(struct sched_group *sg);
2069  
2070  #ifdef CONFIG_SCHED_DEBUG
2071  extern void update_sched_domain_debugfs(void);
2072  extern void dirty_sched_domain_sysctl(int cpu);
2073  #else
update_sched_domain_debugfs(void)2074  static inline void update_sched_domain_debugfs(void) { }
dirty_sched_domain_sysctl(int cpu)2075  static inline void dirty_sched_domain_sysctl(int cpu) { }
2076  #endif
2077  
2078  extern int sched_update_scaling(void);
2079  
task_user_cpus(struct task_struct * p)2080  static inline const struct cpumask *task_user_cpus(struct task_struct *p)
2081  {
2082  	if (!p->user_cpus_ptr)
2083  		return cpu_possible_mask; /* &init_task.cpus_mask */
2084  	return p->user_cpus_ptr;
2085  }
2086  
2087  #endif /* CONFIG_SMP */
2088  
2089  #include "stats.h"
2090  
2091  #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS)
2092  
2093  extern void __sched_core_account_forceidle(struct rq *rq);
2094  
sched_core_account_forceidle(struct rq * rq)2095  static inline void sched_core_account_forceidle(struct rq *rq)
2096  {
2097  	if (schedstat_enabled())
2098  		__sched_core_account_forceidle(rq);
2099  }
2100  
2101  extern void __sched_core_tick(struct rq *rq);
2102  
sched_core_tick(struct rq * rq)2103  static inline void sched_core_tick(struct rq *rq)
2104  {
2105  	if (sched_core_enabled(rq) && schedstat_enabled())
2106  		__sched_core_tick(rq);
2107  }
2108  
2109  #else /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS): */
2110  
sched_core_account_forceidle(struct rq * rq)2111  static inline void sched_core_account_forceidle(struct rq *rq) { }
2112  
sched_core_tick(struct rq * rq)2113  static inline void sched_core_tick(struct rq *rq) { }
2114  
2115  #endif /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS) */
2116  
2117  #ifdef CONFIG_CGROUP_SCHED
2118  
2119  /*
2120   * Return the group to which this tasks belongs.
2121   *
2122   * We cannot use task_css() and friends because the cgroup subsystem
2123   * changes that value before the cgroup_subsys::attach() method is called,
2124   * therefore we cannot pin it and might observe the wrong value.
2125   *
2126   * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
2127   * core changes this before calling sched_move_task().
2128   *
2129   * Instead we use a 'copy' which is updated from sched_move_task() while
2130   * holding both task_struct::pi_lock and rq::lock.
2131   */
task_group(struct task_struct * p)2132  static inline struct task_group *task_group(struct task_struct *p)
2133  {
2134  	return p->sched_task_group;
2135  }
2136  
2137  /* 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)2138  static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
2139  {
2140  #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
2141  	struct task_group *tg = task_group(p);
2142  #endif
2143  
2144  #ifdef CONFIG_FAIR_GROUP_SCHED
2145  	set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
2146  	p->se.cfs_rq = tg->cfs_rq[cpu];
2147  	p->se.parent = tg->se[cpu];
2148  	p->se.depth = tg->se[cpu] ? tg->se[cpu]->depth + 1 : 0;
2149  #endif
2150  
2151  #ifdef CONFIG_RT_GROUP_SCHED
2152  	p->rt.rt_rq  = tg->rt_rq[cpu];
2153  	p->rt.parent = tg->rt_se[cpu];
2154  #endif
2155  }
2156  
2157  #else /* !CONFIG_CGROUP_SCHED: */
2158  
set_task_rq(struct task_struct * p,unsigned int cpu)2159  static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
2160  
task_group(struct task_struct * p)2161  static inline struct task_group *task_group(struct task_struct *p)
2162  {
2163  	return NULL;
2164  }
2165  
2166  #endif /* !CONFIG_CGROUP_SCHED */
2167  
__set_task_cpu(struct task_struct * p,unsigned int cpu)2168  static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
2169  {
2170  	set_task_rq(p, cpu);
2171  #ifdef CONFIG_SMP
2172  	/*
2173  	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
2174  	 * successfully executed on another CPU. We must ensure that updates of
2175  	 * per-task data have been completed by this moment.
2176  	 */
2177  	smp_wmb();
2178  	WRITE_ONCE(task_thread_info(p)->cpu, cpu);
2179  	p->wake_cpu = cpu;
2180  #endif
2181  }
2182  
2183  /*
2184   * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
2185   */
2186  #ifdef CONFIG_SCHED_DEBUG
2187  # define const_debug __read_mostly
2188  #else
2189  # define const_debug const
2190  #endif
2191  
2192  #define SCHED_FEAT(name, enabled)	\
2193  	__SCHED_FEAT_##name ,
2194  
2195  enum {
2196  #include "features.h"
2197  	__SCHED_FEAT_NR,
2198  };
2199  
2200  #undef SCHED_FEAT
2201  
2202  #ifdef CONFIG_SCHED_DEBUG
2203  
2204  /*
2205   * To support run-time toggling of sched features, all the translation units
2206   * (but core.c) reference the sysctl_sched_features defined in core.c.
2207   */
2208  extern const_debug unsigned int sysctl_sched_features;
2209  
2210  #ifdef CONFIG_JUMP_LABEL
2211  
2212  #define SCHED_FEAT(name, enabled)					\
2213  static __always_inline bool static_branch_##name(struct static_key *key) \
2214  {									\
2215  	return static_key_##enabled(key);				\
2216  }
2217  
2218  #include "features.h"
2219  #undef SCHED_FEAT
2220  
2221  extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
2222  #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
2223  
2224  #else /* !CONFIG_JUMP_LABEL: */
2225  
2226  #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2227  
2228  #endif /* !CONFIG_JUMP_LABEL */
2229  
2230  #else /* !SCHED_DEBUG: */
2231  
2232  /*
2233   * Each translation unit has its own copy of sysctl_sched_features to allow
2234   * constants propagation at compile time and compiler optimization based on
2235   * features default.
2236   */
2237  #define SCHED_FEAT(name, enabled)	\
2238  	(1UL << __SCHED_FEAT_##name) * enabled |
2239  static const_debug __maybe_unused unsigned int sysctl_sched_features =
2240  #include "features.h"
2241  	0;
2242  #undef SCHED_FEAT
2243  
2244  #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2245  
2246  #endif /* !SCHED_DEBUG */
2247  
2248  extern struct static_key_false sched_numa_balancing;
2249  extern struct static_key_false sched_schedstats;
2250  
global_rt_period(void)2251  static inline u64 global_rt_period(void)
2252  {
2253  	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
2254  }
2255  
global_rt_runtime(void)2256  static inline u64 global_rt_runtime(void)
2257  {
2258  	if (sysctl_sched_rt_runtime < 0)
2259  		return RUNTIME_INF;
2260  
2261  	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
2262  }
2263  
task_current(struct rq * rq,struct task_struct * p)2264  static inline int task_current(struct rq *rq, struct task_struct *p)
2265  {
2266  	return rq->curr == p;
2267  }
2268  
task_on_cpu(struct rq * rq,struct task_struct * p)2269  static inline int task_on_cpu(struct rq *rq, struct task_struct *p)
2270  {
2271  #ifdef CONFIG_SMP
2272  	return p->on_cpu;
2273  #else
2274  	return task_current(rq, p);
2275  #endif
2276  }
2277  
task_on_rq_queued(struct task_struct * p)2278  static inline int task_on_rq_queued(struct task_struct *p)
2279  {
2280  	return p->on_rq == TASK_ON_RQ_QUEUED;
2281  }
2282  
task_on_rq_migrating(struct task_struct * p)2283  static inline int task_on_rq_migrating(struct task_struct *p)
2284  {
2285  	return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
2286  }
2287  
2288  /* Wake flags. The first three directly map to some SD flag value */
2289  #define WF_EXEC			0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
2290  #define WF_FORK			0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
2291  #define WF_TTWU			0x08 /* Wakeup;            maps to SD_BALANCE_WAKE */
2292  
2293  #define WF_SYNC			0x10 /* Waker goes to sleep after wakeup */
2294  #define WF_MIGRATED		0x20 /* Internal use, task got migrated */
2295  #define WF_CURRENT_CPU		0x40 /* Prefer to move the wakee to the current CPU. */
2296  #define WF_RQ_SELECTED		0x80 /* ->select_task_rq() was called */
2297  
2298  #ifdef CONFIG_SMP
2299  static_assert(WF_EXEC == SD_BALANCE_EXEC);
2300  static_assert(WF_FORK == SD_BALANCE_FORK);
2301  static_assert(WF_TTWU == SD_BALANCE_WAKE);
2302  #endif
2303  
2304  /*
2305   * To aid in avoiding the subversion of "niceness" due to uneven distribution
2306   * of tasks with abnormal "nice" values across CPUs the contribution that
2307   * each task makes to its run queue's load is weighted according to its
2308   * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
2309   * scaled version of the new time slice allocation that they receive on time
2310   * slice expiry etc.
2311   */
2312  
2313  #define WEIGHT_IDLEPRIO		3
2314  #define WMULT_IDLEPRIO		1431655765
2315  
2316  extern const int		sched_prio_to_weight[40];
2317  extern const u32		sched_prio_to_wmult[40];
2318  
2319  /*
2320   * {de,en}queue flags:
2321   *
2322   * DEQUEUE_SLEEP  - task is no longer runnable
2323   * ENQUEUE_WAKEUP - task just became runnable
2324   *
2325   * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
2326   *                are in a known state which allows modification. Such pairs
2327   *                should preserve as much state as possible.
2328   *
2329   * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
2330   *        in the runqueue.
2331   *
2332   * NOCLOCK - skip the update_rq_clock() (avoids double updates)
2333   *
2334   * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE)
2335   *
2336   * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
2337   * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
2338   * ENQUEUE_MIGRATED  - the task was migrated during wakeup
2339   * ENQUEUE_RQ_SELECTED - ->select_task_rq() was called
2340   *
2341   */
2342  
2343  #define DEQUEUE_SLEEP		0x01 /* Matches ENQUEUE_WAKEUP */
2344  #define DEQUEUE_SAVE		0x02 /* Matches ENQUEUE_RESTORE */
2345  #define DEQUEUE_MOVE		0x04 /* Matches ENQUEUE_MOVE */
2346  #define DEQUEUE_NOCLOCK		0x08 /* Matches ENQUEUE_NOCLOCK */
2347  #define DEQUEUE_SPECIAL		0x10
2348  #define DEQUEUE_MIGRATING	0x100 /* Matches ENQUEUE_MIGRATING */
2349  #define DEQUEUE_DELAYED		0x200 /* Matches ENQUEUE_DELAYED */
2350  
2351  #define ENQUEUE_WAKEUP		0x01
2352  #define ENQUEUE_RESTORE		0x02
2353  #define ENQUEUE_MOVE		0x04
2354  #define ENQUEUE_NOCLOCK		0x08
2355  
2356  #define ENQUEUE_HEAD		0x10
2357  #define ENQUEUE_REPLENISH	0x20
2358  #ifdef CONFIG_SMP
2359  #define ENQUEUE_MIGRATED	0x40
2360  #else
2361  #define ENQUEUE_MIGRATED	0x00
2362  #endif
2363  #define ENQUEUE_INITIAL		0x80
2364  #define ENQUEUE_MIGRATING	0x100
2365  #define ENQUEUE_DELAYED		0x200
2366  #define ENQUEUE_RQ_SELECTED	0x400
2367  
2368  #define RETRY_TASK		((void *)-1UL)
2369  
2370  struct affinity_context {
2371  	const struct cpumask	*new_mask;
2372  	struct cpumask		*user_mask;
2373  	unsigned int		flags;
2374  };
2375  
2376  extern s64 update_curr_common(struct rq *rq);
2377  
2378  struct sched_class {
2379  
2380  #ifdef CONFIG_UCLAMP_TASK
2381  	int uclamp_enabled;
2382  #endif
2383  
2384  	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
2385  	bool (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
2386  	void (*yield_task)   (struct rq *rq);
2387  	bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
2388  
2389  	void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags);
2390  
2391  	int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2392  	struct task_struct *(*pick_task)(struct rq *rq);
2393  	/*
2394  	 * Optional! When implemented pick_next_task() should be equivalent to:
2395  	 *
2396  	 *   next = pick_task();
2397  	 *   if (next) {
2398  	 *       put_prev_task(prev);
2399  	 *       set_next_task_first(next);
2400  	 *   }
2401  	 */
2402  	struct task_struct *(*pick_next_task)(struct rq *rq, struct task_struct *prev);
2403  
2404  	void (*put_prev_task)(struct rq *rq, struct task_struct *p, struct task_struct *next);
2405  	void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
2406  
2407  #ifdef CONFIG_SMP
2408  	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
2409  
2410  	void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
2411  
2412  	void (*task_woken)(struct rq *this_rq, struct task_struct *task);
2413  
2414  	void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx);
2415  
2416  	void (*rq_online)(struct rq *rq);
2417  	void (*rq_offline)(struct rq *rq);
2418  
2419  	struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
2420  #endif
2421  
2422  	void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
2423  	void (*task_fork)(struct task_struct *p);
2424  	void (*task_dead)(struct task_struct *p);
2425  
2426  	/*
2427  	 * The switched_from() call is allowed to drop rq->lock, therefore we
2428  	 * cannot assume the switched_from/switched_to pair is serialized by
2429  	 * rq->lock. They are however serialized by p->pi_lock.
2430  	 */
2431  	void (*switching_to) (struct rq *this_rq, struct task_struct *task);
2432  	void (*switched_from)(struct rq *this_rq, struct task_struct *task);
2433  	void (*switched_to)  (struct rq *this_rq, struct task_struct *task);
2434  	void (*reweight_task)(struct rq *this_rq, struct task_struct *task,
2435  			      const struct load_weight *lw);
2436  	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
2437  			      int oldprio);
2438  
2439  	unsigned int (*get_rr_interval)(struct rq *rq,
2440  					struct task_struct *task);
2441  
2442  	void (*update_curr)(struct rq *rq);
2443  
2444  #ifdef CONFIG_FAIR_GROUP_SCHED
2445  	void (*task_change_group)(struct task_struct *p);
2446  #endif
2447  
2448  #ifdef CONFIG_SCHED_CORE
2449  	int (*task_is_throttled)(struct task_struct *p, int cpu);
2450  #endif
2451  };
2452  
put_prev_task(struct rq * rq,struct task_struct * prev)2453  static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
2454  {
2455  	WARN_ON_ONCE(rq->curr != prev);
2456  	prev->sched_class->put_prev_task(rq, prev, NULL);
2457  }
2458  
set_next_task(struct rq * rq,struct task_struct * next)2459  static inline void set_next_task(struct rq *rq, struct task_struct *next)
2460  {
2461  	next->sched_class->set_next_task(rq, next, false);
2462  }
2463  
2464  static inline void
__put_prev_set_next_dl_server(struct rq * rq,struct task_struct * prev,struct task_struct * next)2465  __put_prev_set_next_dl_server(struct rq *rq,
2466  			      struct task_struct *prev,
2467  			      struct task_struct *next)
2468  {
2469  	prev->dl_server = NULL;
2470  	next->dl_server = rq->dl_server;
2471  	rq->dl_server = NULL;
2472  }
2473  
put_prev_set_next_task(struct rq * rq,struct task_struct * prev,struct task_struct * next)2474  static inline void put_prev_set_next_task(struct rq *rq,
2475  					  struct task_struct *prev,
2476  					  struct task_struct *next)
2477  {
2478  	WARN_ON_ONCE(rq->curr != prev);
2479  
2480  	__put_prev_set_next_dl_server(rq, prev, next);
2481  
2482  	if (next == prev)
2483  		return;
2484  
2485  	prev->sched_class->put_prev_task(rq, prev, next);
2486  	next->sched_class->set_next_task(rq, next, true);
2487  }
2488  
2489  /*
2490   * Helper to define a sched_class instance; each one is placed in a separate
2491   * section which is ordered by the linker script:
2492   *
2493   *   include/asm-generic/vmlinux.lds.h
2494   *
2495   * *CAREFUL* they are laid out in *REVERSE* order!!!
2496   *
2497   * Also enforce alignment on the instance, not the type, to guarantee layout.
2498   */
2499  #define DEFINE_SCHED_CLASS(name) \
2500  const struct sched_class name##_sched_class \
2501  	__aligned(__alignof__(struct sched_class)) \
2502  	__section("__" #name "_sched_class")
2503  
2504  /* Defined in include/asm-generic/vmlinux.lds.h */
2505  extern struct sched_class __sched_class_highest[];
2506  extern struct sched_class __sched_class_lowest[];
2507  
2508  extern const struct sched_class stop_sched_class;
2509  extern const struct sched_class dl_sched_class;
2510  extern const struct sched_class rt_sched_class;
2511  extern const struct sched_class fair_sched_class;
2512  extern const struct sched_class idle_sched_class;
2513  
2514  #ifdef CONFIG_SCHED_CLASS_EXT
2515  extern const struct sched_class ext_sched_class;
2516  
2517  DECLARE_STATIC_KEY_FALSE(__scx_ops_enabled);	/* SCX BPF scheduler loaded */
2518  DECLARE_STATIC_KEY_FALSE(__scx_switched_all);	/* all fair class tasks on SCX */
2519  
2520  #define scx_enabled()		static_branch_unlikely(&__scx_ops_enabled)
2521  #define scx_switched_all()	static_branch_unlikely(&__scx_switched_all)
2522  #else /* !CONFIG_SCHED_CLASS_EXT */
2523  #define scx_enabled()		false
2524  #define scx_switched_all()	false
2525  #endif /* !CONFIG_SCHED_CLASS_EXT */
2526  
2527  /*
2528   * Iterate only active classes. SCX can take over all fair tasks or be
2529   * completely disabled. If the former, skip fair. If the latter, skip SCX.
2530   */
next_active_class(const struct sched_class * class)2531  static inline const struct sched_class *next_active_class(const struct sched_class *class)
2532  {
2533  	class++;
2534  #ifdef CONFIG_SCHED_CLASS_EXT
2535  	if (scx_switched_all() && class == &fair_sched_class)
2536  		class++;
2537  	if (!scx_enabled() && class == &ext_sched_class)
2538  		class++;
2539  #endif
2540  	return class;
2541  }
2542  
2543  #define for_class_range(class, _from, _to) \
2544  	for (class = (_from); class < (_to); class++)
2545  
2546  #define for_each_class(class) \
2547  	for_class_range(class, __sched_class_highest, __sched_class_lowest)
2548  
2549  #define for_active_class_range(class, _from, _to)				\
2550  	for (class = (_from); class != (_to); class = next_active_class(class))
2551  
2552  #define for_each_active_class(class)						\
2553  	for_active_class_range(class, __sched_class_highest, __sched_class_lowest)
2554  
2555  #define sched_class_above(_a, _b)	((_a) < (_b))
2556  
sched_stop_runnable(struct rq * rq)2557  static inline bool sched_stop_runnable(struct rq *rq)
2558  {
2559  	return rq->stop && task_on_rq_queued(rq->stop);
2560  }
2561  
sched_dl_runnable(struct rq * rq)2562  static inline bool sched_dl_runnable(struct rq *rq)
2563  {
2564  	return rq->dl.dl_nr_running > 0;
2565  }
2566  
sched_rt_runnable(struct rq * rq)2567  static inline bool sched_rt_runnable(struct rq *rq)
2568  {
2569  	return rq->rt.rt_queued > 0;
2570  }
2571  
sched_fair_runnable(struct rq * rq)2572  static inline bool sched_fair_runnable(struct rq *rq)
2573  {
2574  	return rq->cfs.nr_running > 0;
2575  }
2576  
2577  extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2578  extern struct task_struct *pick_task_idle(struct rq *rq);
2579  
2580  #define SCA_CHECK		0x01
2581  #define SCA_MIGRATE_DISABLE	0x02
2582  #define SCA_MIGRATE_ENABLE	0x04
2583  #define SCA_USER		0x08
2584  
2585  #ifdef CONFIG_SMP
2586  
2587  extern void update_group_capacity(struct sched_domain *sd, int cpu);
2588  
2589  extern void sched_balance_trigger(struct rq *rq);
2590  
2591  extern int __set_cpus_allowed_ptr(struct task_struct *p, struct affinity_context *ctx);
2592  extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx);
2593  
task_allowed_on_cpu(struct task_struct * p,int cpu)2594  static inline bool task_allowed_on_cpu(struct task_struct *p, int cpu)
2595  {
2596  	/* When not in the task's cpumask, no point in looking further. */
2597  	if (!cpumask_test_cpu(cpu, p->cpus_ptr))
2598  		return false;
2599  
2600  	/* Can @cpu run a user thread? */
2601  	if (!(p->flags & PF_KTHREAD) && !task_cpu_possible(cpu, p))
2602  		return false;
2603  
2604  	return true;
2605  }
2606  
alloc_user_cpus_ptr(int node)2607  static inline cpumask_t *alloc_user_cpus_ptr(int node)
2608  {
2609  	/*
2610  	 * See do_set_cpus_allowed() above for the rcu_head usage.
2611  	 */
2612  	int size = max_t(int, cpumask_size(), sizeof(struct rcu_head));
2613  
2614  	return kmalloc_node(size, GFP_KERNEL, node);
2615  }
2616  
get_push_task(struct rq * rq)2617  static inline struct task_struct *get_push_task(struct rq *rq)
2618  {
2619  	struct task_struct *p = rq->curr;
2620  
2621  	lockdep_assert_rq_held(rq);
2622  
2623  	if (rq->push_busy)
2624  		return NULL;
2625  
2626  	if (p->nr_cpus_allowed == 1)
2627  		return NULL;
2628  
2629  	if (p->migration_disabled)
2630  		return NULL;
2631  
2632  	rq->push_busy = true;
2633  	return get_task_struct(p);
2634  }
2635  
2636  extern int push_cpu_stop(void *arg);
2637  
2638  #else /* !CONFIG_SMP: */
2639  
task_allowed_on_cpu(struct task_struct * p,int cpu)2640  static inline bool task_allowed_on_cpu(struct task_struct *p, int cpu)
2641  {
2642  	return true;
2643  }
2644  
__set_cpus_allowed_ptr(struct task_struct * p,struct affinity_context * ctx)2645  static inline int __set_cpus_allowed_ptr(struct task_struct *p,
2646  					 struct affinity_context *ctx)
2647  {
2648  	return set_cpus_allowed_ptr(p, ctx->new_mask);
2649  }
2650  
alloc_user_cpus_ptr(int node)2651  static inline cpumask_t *alloc_user_cpus_ptr(int node)
2652  {
2653  	return NULL;
2654  }
2655  
2656  #endif /* !CONFIG_SMP */
2657  
2658  #ifdef CONFIG_CPU_IDLE
2659  
idle_set_state(struct rq * rq,struct cpuidle_state * idle_state)2660  static inline void idle_set_state(struct rq *rq,
2661  				  struct cpuidle_state *idle_state)
2662  {
2663  	rq->idle_state = idle_state;
2664  }
2665  
idle_get_state(struct rq * rq)2666  static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2667  {
2668  	SCHED_WARN_ON(!rcu_read_lock_held());
2669  
2670  	return rq->idle_state;
2671  }
2672  
2673  #else /* !CONFIG_CPU_IDLE: */
2674  
idle_set_state(struct rq * rq,struct cpuidle_state * idle_state)2675  static inline void idle_set_state(struct rq *rq,
2676  				  struct cpuidle_state *idle_state)
2677  {
2678  }
2679  
idle_get_state(struct rq * rq)2680  static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2681  {
2682  	return NULL;
2683  }
2684  
2685  #endif /* !CONFIG_CPU_IDLE */
2686  
2687  extern void schedule_idle(void);
2688  asmlinkage void schedule_user(void);
2689  
2690  extern void sysrq_sched_debug_show(void);
2691  extern void sched_init_granularity(void);
2692  extern void update_max_interval(void);
2693  
2694  extern void init_sched_dl_class(void);
2695  extern void init_sched_rt_class(void);
2696  extern void init_sched_fair_class(void);
2697  
2698  extern void resched_curr(struct rq *rq);
2699  extern void resched_cpu(int cpu);
2700  
2701  extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
2702  extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq);
2703  
2704  extern void init_dl_entity(struct sched_dl_entity *dl_se);
2705  
2706  #define BW_SHIFT		20
2707  #define BW_UNIT			(1 << BW_SHIFT)
2708  #define RATIO_SHIFT		8
2709  #define MAX_BW_BITS		(64 - BW_SHIFT)
2710  #define MAX_BW			((1ULL << MAX_BW_BITS) - 1)
2711  
2712  extern unsigned long to_ratio(u64 period, u64 runtime);
2713  
2714  extern void init_entity_runnable_average(struct sched_entity *se);
2715  extern void post_init_entity_util_avg(struct task_struct *p);
2716  
2717  #ifdef CONFIG_NO_HZ_FULL
2718  extern bool sched_can_stop_tick(struct rq *rq);
2719  extern int __init sched_tick_offload_init(void);
2720  
2721  /*
2722   * Tick may be needed by tasks in the runqueue depending on their policy and
2723   * requirements. If tick is needed, lets send the target an IPI to kick it out of
2724   * nohz mode if necessary.
2725   */
sched_update_tick_dependency(struct rq * rq)2726  static inline void sched_update_tick_dependency(struct rq *rq)
2727  {
2728  	int cpu = cpu_of(rq);
2729  
2730  	if (!tick_nohz_full_cpu(cpu))
2731  		return;
2732  
2733  	if (sched_can_stop_tick(rq))
2734  		tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
2735  	else
2736  		tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
2737  }
2738  #else /* !CONFIG_NO_HZ_FULL: */
sched_tick_offload_init(void)2739  static inline int sched_tick_offload_init(void) { return 0; }
sched_update_tick_dependency(struct rq * rq)2740  static inline void sched_update_tick_dependency(struct rq *rq) { }
2741  #endif /* !CONFIG_NO_HZ_FULL */
2742  
add_nr_running(struct rq * rq,unsigned count)2743  static inline void add_nr_running(struct rq *rq, unsigned count)
2744  {
2745  	unsigned prev_nr = rq->nr_running;
2746  
2747  	rq->nr_running = prev_nr + count;
2748  	if (trace_sched_update_nr_running_tp_enabled()) {
2749  		call_trace_sched_update_nr_running(rq, count);
2750  	}
2751  
2752  #ifdef CONFIG_SMP
2753  	if (prev_nr < 2 && rq->nr_running >= 2)
2754  		set_rd_overloaded(rq->rd, 1);
2755  #endif
2756  
2757  	sched_update_tick_dependency(rq);
2758  }
2759  
sub_nr_running(struct rq * rq,unsigned count)2760  static inline void sub_nr_running(struct rq *rq, unsigned count)
2761  {
2762  	rq->nr_running -= count;
2763  	if (trace_sched_update_nr_running_tp_enabled()) {
2764  		call_trace_sched_update_nr_running(rq, -count);
2765  	}
2766  
2767  	/* Check if we still need preemption */
2768  	sched_update_tick_dependency(rq);
2769  }
2770  
__block_task(struct rq * rq,struct task_struct * p)2771  static inline void __block_task(struct rq *rq, struct task_struct *p)
2772  {
2773  	if (p->sched_contributes_to_load)
2774  		rq->nr_uninterruptible++;
2775  
2776  	if (p->in_iowait) {
2777  		atomic_inc(&rq->nr_iowait);
2778  		delayacct_blkio_start();
2779  	}
2780  
2781  	ASSERT_EXCLUSIVE_WRITER(p->on_rq);
2782  
2783  	/*
2784  	 * The moment this write goes through, ttwu() can swoop in and migrate
2785  	 * this task, rendering our rq->__lock ineffective.
2786  	 *
2787  	 * __schedule()				try_to_wake_up()
2788  	 *   LOCK rq->__lock			  LOCK p->pi_lock
2789  	 *   pick_next_task()
2790  	 *     pick_next_task_fair()
2791  	 *       pick_next_entity()
2792  	 *         dequeue_entities()
2793  	 *           __block_task()
2794  	 *             RELEASE p->on_rq = 0	  if (p->on_rq && ...)
2795  	 *					    break;
2796  	 *
2797  	 *					  ACQUIRE (after ctrl-dep)
2798  	 *
2799  	 *					  cpu = select_task_rq();
2800  	 *					  set_task_cpu(p, cpu);
2801  	 *					  ttwu_queue()
2802  	 *					    ttwu_do_activate()
2803  	 *					      LOCK rq->__lock
2804  	 *					      activate_task()
2805  	 *					        STORE p->on_rq = 1
2806  	 *   UNLOCK rq->__lock
2807  	 *
2808  	 * Callers must ensure to not reference @p after this -- we no longer
2809  	 * own it.
2810  	 */
2811  	smp_store_release(&p->on_rq, 0);
2812  }
2813  
2814  extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
2815  extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
2816  
2817  extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags);
2818  
2819  #ifdef CONFIG_PREEMPT_RT
2820  # define SCHED_NR_MIGRATE_BREAK 8
2821  #else
2822  # define SCHED_NR_MIGRATE_BREAK 32
2823  #endif
2824  
2825  extern const_debug unsigned int sysctl_sched_nr_migrate;
2826  extern const_debug unsigned int sysctl_sched_migration_cost;
2827  
2828  extern unsigned int sysctl_sched_base_slice;
2829  
2830  #ifdef CONFIG_SCHED_DEBUG
2831  extern int sysctl_resched_latency_warn_ms;
2832  extern int sysctl_resched_latency_warn_once;
2833  
2834  extern unsigned int sysctl_sched_tunable_scaling;
2835  
2836  extern unsigned int sysctl_numa_balancing_scan_delay;
2837  extern unsigned int sysctl_numa_balancing_scan_period_min;
2838  extern unsigned int sysctl_numa_balancing_scan_period_max;
2839  extern unsigned int sysctl_numa_balancing_scan_size;
2840  extern unsigned int sysctl_numa_balancing_hot_threshold;
2841  #endif
2842  
2843  #ifdef CONFIG_SCHED_HRTICK
2844  
2845  /*
2846   * Use hrtick when:
2847   *  - enabled by features
2848   *  - hrtimer is actually high res
2849   */
hrtick_enabled(struct rq * rq)2850  static inline int hrtick_enabled(struct rq *rq)
2851  {
2852  	if (!cpu_active(cpu_of(rq)))
2853  		return 0;
2854  	return hrtimer_is_hres_active(&rq->hrtick_timer);
2855  }
2856  
hrtick_enabled_fair(struct rq * rq)2857  static inline int hrtick_enabled_fair(struct rq *rq)
2858  {
2859  	if (!sched_feat(HRTICK))
2860  		return 0;
2861  	return hrtick_enabled(rq);
2862  }
2863  
hrtick_enabled_dl(struct rq * rq)2864  static inline int hrtick_enabled_dl(struct rq *rq)
2865  {
2866  	if (!sched_feat(HRTICK_DL))
2867  		return 0;
2868  	return hrtick_enabled(rq);
2869  }
2870  
2871  extern void hrtick_start(struct rq *rq, u64 delay);
2872  
2873  #else /* !CONFIG_SCHED_HRTICK: */
2874  
hrtick_enabled_fair(struct rq * rq)2875  static inline int hrtick_enabled_fair(struct rq *rq)
2876  {
2877  	return 0;
2878  }
2879  
hrtick_enabled_dl(struct rq * rq)2880  static inline int hrtick_enabled_dl(struct rq *rq)
2881  {
2882  	return 0;
2883  }
2884  
hrtick_enabled(struct rq * rq)2885  static inline int hrtick_enabled(struct rq *rq)
2886  {
2887  	return 0;
2888  }
2889  
2890  #endif /* !CONFIG_SCHED_HRTICK */
2891  
2892  #ifndef arch_scale_freq_tick
arch_scale_freq_tick(void)2893  static __always_inline void arch_scale_freq_tick(void) { }
2894  #endif
2895  
2896  #ifndef arch_scale_freq_capacity
2897  /**
2898   * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
2899   * @cpu: the CPU in question.
2900   *
2901   * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
2902   *
2903   *     f_curr
2904   *     ------ * SCHED_CAPACITY_SCALE
2905   *     f_max
2906   */
2907  static __always_inline
arch_scale_freq_capacity(int cpu)2908  unsigned long arch_scale_freq_capacity(int cpu)
2909  {
2910  	return SCHED_CAPACITY_SCALE;
2911  }
2912  #endif
2913  
2914  #ifdef CONFIG_SCHED_DEBUG
2915  /*
2916   * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to
2917   * acquire rq lock instead of rq_lock(). So at the end of these two functions
2918   * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of
2919   * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning.
2920   */
double_rq_clock_clear_update(struct rq * rq1,struct rq * rq2)2921  static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2)
2922  {
2923  	rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
2924  	/* rq1 == rq2 for !CONFIG_SMP, so just clear RQCF_UPDATED once. */
2925  #ifdef CONFIG_SMP
2926  	rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
2927  #endif
2928  }
2929  #else
double_rq_clock_clear_update(struct rq * rq1,struct rq * rq2)2930  static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2) { }
2931  #endif
2932  
2933  #define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...)				\
2934  __DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__)			\
2935  static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2)	\
2936  { class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t;			\
2937    _lock; return _t; }
2938  
2939  #ifdef CONFIG_SMP
2940  
rq_order_less(struct rq * rq1,struct rq * rq2)2941  static inline bool rq_order_less(struct rq *rq1, struct rq *rq2)
2942  {
2943  #ifdef CONFIG_SCHED_CORE
2944  	/*
2945  	 * In order to not have {0,2},{1,3} turn into into an AB-BA,
2946  	 * order by core-id first and cpu-id second.
2947  	 *
2948  	 * Notably:
2949  	 *
2950  	 *	double_rq_lock(0,3); will take core-0, core-1 lock
2951  	 *	double_rq_lock(1,2); will take core-1, core-0 lock
2952  	 *
2953  	 * when only cpu-id is considered.
2954  	 */
2955  	if (rq1->core->cpu < rq2->core->cpu)
2956  		return true;
2957  	if (rq1->core->cpu > rq2->core->cpu)
2958  		return false;
2959  
2960  	/*
2961  	 * __sched_core_flip() relies on SMT having cpu-id lock order.
2962  	 */
2963  #endif
2964  	return rq1->cpu < rq2->cpu;
2965  }
2966  
2967  extern void double_rq_lock(struct rq *rq1, struct rq *rq2);
2968  
2969  #ifdef CONFIG_PREEMPTION
2970  
2971  /*
2972   * fair double_lock_balance: Safely acquires both rq->locks in a fair
2973   * way at the expense of forcing extra atomic operations in all
2974   * invocations.  This assures that the double_lock is acquired using the
2975   * same underlying policy as the spinlock_t on this architecture, which
2976   * reduces latency compared to the unfair variant below.  However, it
2977   * also adds more overhead and therefore may reduce throughput.
2978   */
_double_lock_balance(struct rq * this_rq,struct rq * busiest)2979  static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2980  	__releases(this_rq->lock)
2981  	__acquires(busiest->lock)
2982  	__acquires(this_rq->lock)
2983  {
2984  	raw_spin_rq_unlock(this_rq);
2985  	double_rq_lock(this_rq, busiest);
2986  
2987  	return 1;
2988  }
2989  
2990  #else /* !CONFIG_PREEMPTION: */
2991  /*
2992   * Unfair double_lock_balance: Optimizes throughput at the expense of
2993   * latency by eliminating extra atomic operations when the locks are
2994   * already in proper order on entry.  This favors lower CPU-ids and will
2995   * grant the double lock to lower CPUs over higher ids under contention,
2996   * regardless of entry order into the function.
2997   */
_double_lock_balance(struct rq * this_rq,struct rq * busiest)2998  static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2999  	__releases(this_rq->lock)
3000  	__acquires(busiest->lock)
3001  	__acquires(this_rq->lock)
3002  {
3003  	if (__rq_lockp(this_rq) == __rq_lockp(busiest) ||
3004  	    likely(raw_spin_rq_trylock(busiest))) {
3005  		double_rq_clock_clear_update(this_rq, busiest);
3006  		return 0;
3007  	}
3008  
3009  	if (rq_order_less(this_rq, busiest)) {
3010  		raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING);
3011  		double_rq_clock_clear_update(this_rq, busiest);
3012  		return 0;
3013  	}
3014  
3015  	raw_spin_rq_unlock(this_rq);
3016  	double_rq_lock(this_rq, busiest);
3017  
3018  	return 1;
3019  }
3020  
3021  #endif /* !CONFIG_PREEMPTION */
3022  
3023  /*
3024   * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
3025   */
double_lock_balance(struct rq * this_rq,struct rq * busiest)3026  static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
3027  {
3028  	lockdep_assert_irqs_disabled();
3029  
3030  	return _double_lock_balance(this_rq, busiest);
3031  }
3032  
double_unlock_balance(struct rq * this_rq,struct rq * busiest)3033  static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
3034  	__releases(busiest->lock)
3035  {
3036  	if (__rq_lockp(this_rq) != __rq_lockp(busiest))
3037  		raw_spin_rq_unlock(busiest);
3038  	lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_);
3039  }
3040  
double_lock(spinlock_t * l1,spinlock_t * l2)3041  static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
3042  {
3043  	if (l1 > l2)
3044  		swap(l1, l2);
3045  
3046  	spin_lock(l1);
3047  	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3048  }
3049  
double_lock_irq(spinlock_t * l1,spinlock_t * l2)3050  static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
3051  {
3052  	if (l1 > l2)
3053  		swap(l1, l2);
3054  
3055  	spin_lock_irq(l1);
3056  	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3057  }
3058  
double_raw_lock(raw_spinlock_t * l1,raw_spinlock_t * l2)3059  static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
3060  {
3061  	if (l1 > l2)
3062  		swap(l1, l2);
3063  
3064  	raw_spin_lock(l1);
3065  	raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3066  }
3067  
double_raw_unlock(raw_spinlock_t * l1,raw_spinlock_t * l2)3068  static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2)
3069  {
3070  	raw_spin_unlock(l1);
3071  	raw_spin_unlock(l2);
3072  }
3073  
3074  DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t,
3075  		    double_raw_lock(_T->lock, _T->lock2),
3076  		    double_raw_unlock(_T->lock, _T->lock2))
3077  
3078  /*
3079   * double_rq_unlock - safely unlock two runqueues
3080   *
3081   * Note this does not restore interrupts like task_rq_unlock,
3082   * you need to do so manually after calling.
3083   */
double_rq_unlock(struct rq * rq1,struct rq * rq2)3084  static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
3085  	__releases(rq1->lock)
3086  	__releases(rq2->lock)
3087  {
3088  	if (__rq_lockp(rq1) != __rq_lockp(rq2))
3089  		raw_spin_rq_unlock(rq2);
3090  	else
3091  		__release(rq2->lock);
3092  	raw_spin_rq_unlock(rq1);
3093  }
3094  
3095  extern void set_rq_online (struct rq *rq);
3096  extern void set_rq_offline(struct rq *rq);
3097  
3098  extern bool sched_smp_initialized;
3099  
3100  #else /* !CONFIG_SMP: */
3101  
3102  /*
3103   * double_rq_lock - safely lock two runqueues
3104   *
3105   * Note this does not disable interrupts like task_rq_lock,
3106   * you need to do so manually before calling.
3107   */
double_rq_lock(struct rq * rq1,struct rq * rq2)3108  static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
3109  	__acquires(rq1->lock)
3110  	__acquires(rq2->lock)
3111  {
3112  	WARN_ON_ONCE(!irqs_disabled());
3113  	WARN_ON_ONCE(rq1 != rq2);
3114  	raw_spin_rq_lock(rq1);
3115  	__acquire(rq2->lock);	/* Fake it out ;) */
3116  	double_rq_clock_clear_update(rq1, rq2);
3117  }
3118  
3119  /*
3120   * double_rq_unlock - safely unlock two runqueues
3121   *
3122   * Note this does not restore interrupts like task_rq_unlock,
3123   * you need to do so manually after calling.
3124   */
double_rq_unlock(struct rq * rq1,struct rq * rq2)3125  static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
3126  	__releases(rq1->lock)
3127  	__releases(rq2->lock)
3128  {
3129  	WARN_ON_ONCE(rq1 != rq2);
3130  	raw_spin_rq_unlock(rq1);
3131  	__release(rq2->lock);
3132  }
3133  
3134  #endif /* !CONFIG_SMP */
3135  
3136  DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq,
3137  		    double_rq_lock(_T->lock, _T->lock2),
3138  		    double_rq_unlock(_T->lock, _T->lock2))
3139  
3140  extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq);
3141  extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
3142  extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
3143  
3144  #ifdef	CONFIG_SCHED_DEBUG
3145  extern bool sched_debug_verbose;
3146  
3147  extern void print_cfs_stats(struct seq_file *m, int cpu);
3148  extern void print_rt_stats(struct seq_file *m, int cpu);
3149  extern void print_dl_stats(struct seq_file *m, int cpu);
3150  extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
3151  extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
3152  extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
3153  
3154  extern void resched_latency_warn(int cpu, u64 latency);
3155  # ifdef CONFIG_NUMA_BALANCING
3156  extern void show_numa_stats(struct task_struct *p, struct seq_file *m);
3157  extern void
3158  print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
3159  		 unsigned long tpf, unsigned long gsf, unsigned long gpf);
3160  # endif /* CONFIG_NUMA_BALANCING */
3161  #else /* !CONFIG_SCHED_DEBUG: */
resched_latency_warn(int cpu,u64 latency)3162  static inline void resched_latency_warn(int cpu, u64 latency) { }
3163  #endif /* !CONFIG_SCHED_DEBUG */
3164  
3165  extern void init_cfs_rq(struct cfs_rq *cfs_rq);
3166  extern void init_rt_rq(struct rt_rq *rt_rq);
3167  extern void init_dl_rq(struct dl_rq *dl_rq);
3168  
3169  extern void cfs_bandwidth_usage_inc(void);
3170  extern void cfs_bandwidth_usage_dec(void);
3171  
3172  #ifdef CONFIG_NO_HZ_COMMON
3173  
3174  #define NOHZ_BALANCE_KICK_BIT	0
3175  #define NOHZ_STATS_KICK_BIT	1
3176  #define NOHZ_NEWILB_KICK_BIT	2
3177  #define NOHZ_NEXT_KICK_BIT	3
3178  
3179  /* Run sched_balance_domains() */
3180  #define NOHZ_BALANCE_KICK	BIT(NOHZ_BALANCE_KICK_BIT)
3181  /* Update blocked load */
3182  #define NOHZ_STATS_KICK		BIT(NOHZ_STATS_KICK_BIT)
3183  /* Update blocked load when entering idle */
3184  #define NOHZ_NEWILB_KICK	BIT(NOHZ_NEWILB_KICK_BIT)
3185  /* Update nohz.next_balance */
3186  #define NOHZ_NEXT_KICK		BIT(NOHZ_NEXT_KICK_BIT)
3187  
3188  #define NOHZ_KICK_MASK		(NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK)
3189  
3190  #define nohz_flags(cpu)		(&cpu_rq(cpu)->nohz_flags)
3191  
3192  extern void nohz_balance_exit_idle(struct rq *rq);
3193  #else /* !CONFIG_NO_HZ_COMMON: */
nohz_balance_exit_idle(struct rq * rq)3194  static inline void nohz_balance_exit_idle(struct rq *rq) { }
3195  #endif /* !CONFIG_NO_HZ_COMMON */
3196  
3197  #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
3198  extern void nohz_run_idle_balance(int cpu);
3199  #else
nohz_run_idle_balance(int cpu)3200  static inline void nohz_run_idle_balance(int cpu) { }
3201  #endif
3202  
3203  #ifdef CONFIG_IRQ_TIME_ACCOUNTING
3204  
3205  struct irqtime {
3206  	u64			total;
3207  	u64			tick_delta;
3208  	u64			irq_start_time;
3209  	struct u64_stats_sync	sync;
3210  };
3211  
3212  DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
3213  
3214  /*
3215   * Returns the irqtime minus the softirq time computed by ksoftirqd.
3216   * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime
3217   * and never move forward.
3218   */
irq_time_read(int cpu)3219  static inline u64 irq_time_read(int cpu)
3220  {
3221  	struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
3222  	unsigned int seq;
3223  	u64 total;
3224  
3225  	do {
3226  		seq = __u64_stats_fetch_begin(&irqtime->sync);
3227  		total = irqtime->total;
3228  	} while (__u64_stats_fetch_retry(&irqtime->sync, seq));
3229  
3230  	return total;
3231  }
3232  
3233  #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
3234  
3235  #ifdef CONFIG_CPU_FREQ
3236  
3237  DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
3238  
3239  /**
3240   * cpufreq_update_util - Take a note about CPU utilization changes.
3241   * @rq: Runqueue to carry out the update for.
3242   * @flags: Update reason flags.
3243   *
3244   * This function is called by the scheduler on the CPU whose utilization is
3245   * being updated.
3246   *
3247   * It can only be called from RCU-sched read-side critical sections.
3248   *
3249   * The way cpufreq is currently arranged requires it to evaluate the CPU
3250   * performance state (frequency/voltage) on a regular basis to prevent it from
3251   * being stuck in a completely inadequate performance level for too long.
3252   * That is not guaranteed to happen if the updates are only triggered from CFS
3253   * and DL, though, because they may not be coming in if only RT tasks are
3254   * active all the time (or there are RT tasks only).
3255   *
3256   * As a workaround for that issue, this function is called periodically by the
3257   * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
3258   * but that really is a band-aid.  Going forward it should be replaced with
3259   * solutions targeted more specifically at RT tasks.
3260   */
cpufreq_update_util(struct rq * rq,unsigned int flags)3261  static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
3262  {
3263  	struct update_util_data *data;
3264  
3265  	data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
3266  						  cpu_of(rq)));
3267  	if (data)
3268  		data->func(data, rq_clock(rq), flags);
3269  }
3270  #else /* !CONFIG_CPU_FREQ: */
cpufreq_update_util(struct rq * rq,unsigned int flags)3271  static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) { }
3272  #endif /* !CONFIG_CPU_FREQ */
3273  
3274  #ifdef arch_scale_freq_capacity
3275  # ifndef arch_scale_freq_invariant
3276  #  define arch_scale_freq_invariant()	true
3277  # endif
3278  #else
3279  # define arch_scale_freq_invariant()	false
3280  #endif
3281  
3282  #ifdef CONFIG_SMP
3283  
3284  unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
3285  				 unsigned long *min,
3286  				 unsigned long *max);
3287  
3288  unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual,
3289  				 unsigned long min,
3290  				 unsigned long max);
3291  
3292  
3293  /*
3294   * Verify the fitness of task @p to run on @cpu taking into account the
3295   * CPU original capacity and the runtime/deadline ratio of the task.
3296   *
3297   * The function will return true if the original capacity of @cpu is
3298   * greater than or equal to task's deadline density right shifted by
3299   * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise.
3300   */
dl_task_fits_capacity(struct task_struct * p,int cpu)3301  static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
3302  {
3303  	unsigned long cap = arch_scale_cpu_capacity(cpu);
3304  
3305  	return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT);
3306  }
3307  
cpu_bw_dl(struct rq * rq)3308  static inline unsigned long cpu_bw_dl(struct rq *rq)
3309  {
3310  	return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
3311  }
3312  
cpu_util_dl(struct rq * rq)3313  static inline unsigned long cpu_util_dl(struct rq *rq)
3314  {
3315  	return READ_ONCE(rq->avg_dl.util_avg);
3316  }
3317  
3318  
3319  extern unsigned long cpu_util_cfs(int cpu);
3320  extern unsigned long cpu_util_cfs_boost(int cpu);
3321  
cpu_util_rt(struct rq * rq)3322  static inline unsigned long cpu_util_rt(struct rq *rq)
3323  {
3324  	return READ_ONCE(rq->avg_rt.util_avg);
3325  }
3326  
3327  #else /* !CONFIG_SMP */
update_other_load_avgs(struct rq * rq)3328  static inline bool update_other_load_avgs(struct rq *rq) { return false; }
3329  #endif /* CONFIG_SMP */
3330  
3331  #ifdef CONFIG_UCLAMP_TASK
3332  
3333  unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
3334  
uclamp_rq_get(struct rq * rq,enum uclamp_id clamp_id)3335  static inline unsigned long uclamp_rq_get(struct rq *rq,
3336  					  enum uclamp_id clamp_id)
3337  {
3338  	return READ_ONCE(rq->uclamp[clamp_id].value);
3339  }
3340  
uclamp_rq_set(struct rq * rq,enum uclamp_id clamp_id,unsigned int value)3341  static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id,
3342  				 unsigned int value)
3343  {
3344  	WRITE_ONCE(rq->uclamp[clamp_id].value, value);
3345  }
3346  
uclamp_rq_is_idle(struct rq * rq)3347  static inline bool uclamp_rq_is_idle(struct rq *rq)
3348  {
3349  	return rq->uclamp_flags & UCLAMP_FLAG_IDLE;
3350  }
3351  
3352  /* Is the rq being capped/throttled by uclamp_max? */
uclamp_rq_is_capped(struct rq * rq)3353  static inline bool uclamp_rq_is_capped(struct rq *rq)
3354  {
3355  	unsigned long rq_util;
3356  	unsigned long max_util;
3357  
3358  	if (!static_branch_likely(&sched_uclamp_used))
3359  		return false;
3360  
3361  	rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq);
3362  	max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
3363  
3364  	return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util;
3365  }
3366  
3367  /*
3368   * When uclamp is compiled in, the aggregation at rq level is 'turned off'
3369   * by default in the fast path and only gets turned on once userspace performs
3370   * an operation that requires it.
3371   *
3372   * Returns true if userspace opted-in to use uclamp and aggregation at rq level
3373   * hence is active.
3374   */
uclamp_is_used(void)3375  static inline bool uclamp_is_used(void)
3376  {
3377  	return static_branch_likely(&sched_uclamp_used);
3378  }
3379  
3380  #define for_each_clamp_id(clamp_id) \
3381  	for ((clamp_id) = 0; (clamp_id) < UCLAMP_CNT; (clamp_id)++)
3382  
3383  extern unsigned int sysctl_sched_uclamp_util_min_rt_default;
3384  
3385  
uclamp_none(enum uclamp_id clamp_id)3386  static inline unsigned int uclamp_none(enum uclamp_id clamp_id)
3387  {
3388  	if (clamp_id == UCLAMP_MIN)
3389  		return 0;
3390  	return SCHED_CAPACITY_SCALE;
3391  }
3392  
3393  /* Integer rounded range for each bucket */
3394  #define UCLAMP_BUCKET_DELTA DIV_ROUND_CLOSEST(SCHED_CAPACITY_SCALE, UCLAMP_BUCKETS)
3395  
uclamp_bucket_id(unsigned int clamp_value)3396  static inline unsigned int uclamp_bucket_id(unsigned int clamp_value)
3397  {
3398  	return min_t(unsigned int, clamp_value / UCLAMP_BUCKET_DELTA, UCLAMP_BUCKETS - 1);
3399  }
3400  
3401  static inline void
uclamp_se_set(struct uclamp_se * uc_se,unsigned int value,bool user_defined)3402  uclamp_se_set(struct uclamp_se *uc_se, unsigned int value, bool user_defined)
3403  {
3404  	uc_se->value = value;
3405  	uc_se->bucket_id = uclamp_bucket_id(value);
3406  	uc_se->user_defined = user_defined;
3407  }
3408  
3409  #else /* !CONFIG_UCLAMP_TASK: */
3410  
3411  static inline unsigned long
uclamp_eff_value(struct task_struct * p,enum uclamp_id clamp_id)3412  uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id)
3413  {
3414  	if (clamp_id == UCLAMP_MIN)
3415  		return 0;
3416  
3417  	return SCHED_CAPACITY_SCALE;
3418  }
3419  
uclamp_rq_is_capped(struct rq * rq)3420  static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; }
3421  
uclamp_is_used(void)3422  static inline bool uclamp_is_used(void)
3423  {
3424  	return false;
3425  }
3426  
3427  static inline unsigned long
uclamp_rq_get(struct rq * rq,enum uclamp_id clamp_id)3428  uclamp_rq_get(struct rq *rq, enum uclamp_id clamp_id)
3429  {
3430  	if (clamp_id == UCLAMP_MIN)
3431  		return 0;
3432  
3433  	return SCHED_CAPACITY_SCALE;
3434  }
3435  
3436  static inline void
uclamp_rq_set(struct rq * rq,enum uclamp_id clamp_id,unsigned int value)3437  uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, unsigned int value)
3438  {
3439  }
3440  
uclamp_rq_is_idle(struct rq * rq)3441  static inline bool uclamp_rq_is_idle(struct rq *rq)
3442  {
3443  	return false;
3444  }
3445  
3446  #endif /* !CONFIG_UCLAMP_TASK */
3447  
3448  #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
3449  
cpu_util_irq(struct rq * rq)3450  static inline unsigned long cpu_util_irq(struct rq *rq)
3451  {
3452  	return READ_ONCE(rq->avg_irq.util_avg);
3453  }
3454  
3455  static inline
scale_irq_capacity(unsigned long util,unsigned long irq,unsigned long max)3456  unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3457  {
3458  	util *= (max - irq);
3459  	util /= max;
3460  
3461  	return util;
3462  
3463  }
3464  
3465  #else /* !CONFIG_HAVE_SCHED_AVG_IRQ: */
3466  
cpu_util_irq(struct rq * rq)3467  static inline unsigned long cpu_util_irq(struct rq *rq)
3468  {
3469  	return 0;
3470  }
3471  
3472  static inline
scale_irq_capacity(unsigned long util,unsigned long irq,unsigned long max)3473  unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3474  {
3475  	return util;
3476  }
3477  
3478  #endif /* !CONFIG_HAVE_SCHED_AVG_IRQ */
3479  
3480  #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
3481  
3482  #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
3483  
3484  DECLARE_STATIC_KEY_FALSE(sched_energy_present);
3485  
sched_energy_enabled(void)3486  static inline bool sched_energy_enabled(void)
3487  {
3488  	return static_branch_unlikely(&sched_energy_present);
3489  }
3490  
3491  extern struct cpufreq_governor schedutil_gov;
3492  
3493  #else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
3494  
3495  #define perf_domain_span(pd) NULL
3496  
sched_energy_enabled(void)3497  static inline bool sched_energy_enabled(void) { return false; }
3498  
3499  #endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
3500  
3501  #ifdef CONFIG_MEMBARRIER
3502  
3503  /*
3504   * The scheduler provides memory barriers required by membarrier between:
3505   * - prior user-space memory accesses and store to rq->membarrier_state,
3506   * - store to rq->membarrier_state and following user-space memory accesses.
3507   * In the same way it provides those guarantees around store to rq->curr.
3508   */
membarrier_switch_mm(struct rq * rq,struct mm_struct * prev_mm,struct mm_struct * next_mm)3509  static inline void membarrier_switch_mm(struct rq *rq,
3510  					struct mm_struct *prev_mm,
3511  					struct mm_struct *next_mm)
3512  {
3513  	int membarrier_state;
3514  
3515  	if (prev_mm == next_mm)
3516  		return;
3517  
3518  	membarrier_state = atomic_read(&next_mm->membarrier_state);
3519  	if (READ_ONCE(rq->membarrier_state) == membarrier_state)
3520  		return;
3521  
3522  	WRITE_ONCE(rq->membarrier_state, membarrier_state);
3523  }
3524  
3525  #else /* !CONFIG_MEMBARRIER :*/
3526  
membarrier_switch_mm(struct rq * rq,struct mm_struct * prev_mm,struct mm_struct * next_mm)3527  static inline void membarrier_switch_mm(struct rq *rq,
3528  					struct mm_struct *prev_mm,
3529  					struct mm_struct *next_mm)
3530  {
3531  }
3532  
3533  #endif /* !CONFIG_MEMBARRIER */
3534  
3535  #ifdef CONFIG_SMP
is_per_cpu_kthread(struct task_struct * p)3536  static inline bool is_per_cpu_kthread(struct task_struct *p)
3537  {
3538  	if (!(p->flags & PF_KTHREAD))
3539  		return false;
3540  
3541  	if (p->nr_cpus_allowed != 1)
3542  		return false;
3543  
3544  	return true;
3545  }
3546  #endif
3547  
3548  extern void swake_up_all_locked(struct swait_queue_head *q);
3549  extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
3550  
3551  extern int try_to_wake_up(struct task_struct *tsk, unsigned int state, int wake_flags);
3552  
3553  #ifdef CONFIG_PREEMPT_DYNAMIC
3554  extern int preempt_dynamic_mode;
3555  extern int sched_dynamic_mode(const char *str);
3556  extern void sched_dynamic_update(int mode);
3557  #endif
3558  
3559  #ifdef CONFIG_SCHED_MM_CID
3560  
3561  #define SCHED_MM_CID_PERIOD_NS	(100ULL * 1000000)	/* 100ms */
3562  #define MM_CID_SCAN_DELAY	100			/* 100ms */
3563  
3564  extern raw_spinlock_t cid_lock;
3565  extern int use_cid_lock;
3566  
3567  extern void sched_mm_cid_migrate_from(struct task_struct *t);
3568  extern void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t);
3569  extern void task_tick_mm_cid(struct rq *rq, struct task_struct *curr);
3570  extern void init_sched_mm_cid(struct task_struct *t);
3571  
__mm_cid_put(struct mm_struct * mm,int cid)3572  static inline void __mm_cid_put(struct mm_struct *mm, int cid)
3573  {
3574  	if (cid < 0)
3575  		return;
3576  	cpumask_clear_cpu(cid, mm_cidmask(mm));
3577  }
3578  
3579  /*
3580   * The per-mm/cpu cid can have the MM_CID_LAZY_PUT flag set or transition to
3581   * the MM_CID_UNSET state without holding the rq lock, but the rq lock needs to
3582   * be held to transition to other states.
3583   *
3584   * State transitions synchronized with cmpxchg or try_cmpxchg need to be
3585   * consistent across CPUs, which prevents use of this_cpu_cmpxchg.
3586   */
mm_cid_put_lazy(struct task_struct * t)3587  static inline void mm_cid_put_lazy(struct task_struct *t)
3588  {
3589  	struct mm_struct *mm = t->mm;
3590  	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3591  	int cid;
3592  
3593  	lockdep_assert_irqs_disabled();
3594  	cid = __this_cpu_read(pcpu_cid->cid);
3595  	if (!mm_cid_is_lazy_put(cid) ||
3596  	    !try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET))
3597  		return;
3598  	__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3599  }
3600  
mm_cid_pcpu_unset(struct mm_struct * mm)3601  static inline int mm_cid_pcpu_unset(struct mm_struct *mm)
3602  {
3603  	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3604  	int cid, res;
3605  
3606  	lockdep_assert_irqs_disabled();
3607  	cid = __this_cpu_read(pcpu_cid->cid);
3608  	for (;;) {
3609  		if (mm_cid_is_unset(cid))
3610  			return MM_CID_UNSET;
3611  		/*
3612  		 * Attempt transition from valid or lazy-put to unset.
3613  		 */
3614  		res = cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, cid, MM_CID_UNSET);
3615  		if (res == cid)
3616  			break;
3617  		cid = res;
3618  	}
3619  	return cid;
3620  }
3621  
mm_cid_put(struct mm_struct * mm)3622  static inline void mm_cid_put(struct mm_struct *mm)
3623  {
3624  	int cid;
3625  
3626  	lockdep_assert_irqs_disabled();
3627  	cid = mm_cid_pcpu_unset(mm);
3628  	if (cid == MM_CID_UNSET)
3629  		return;
3630  	__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3631  }
3632  
__mm_cid_try_get(struct mm_struct * mm)3633  static inline int __mm_cid_try_get(struct mm_struct *mm)
3634  {
3635  	struct cpumask *cpumask;
3636  	int cid;
3637  
3638  	cpumask = mm_cidmask(mm);
3639  	/*
3640  	 * Retry finding first zero bit if the mask is temporarily
3641  	 * filled. This only happens during concurrent remote-clear
3642  	 * which owns a cid without holding a rq lock.
3643  	 */
3644  	for (;;) {
3645  		cid = cpumask_first_zero(cpumask);
3646  		if (cid < nr_cpu_ids)
3647  			break;
3648  		cpu_relax();
3649  	}
3650  	if (cpumask_test_and_set_cpu(cid, cpumask))
3651  		return -1;
3652  
3653  	return cid;
3654  }
3655  
3656  /*
3657   * Save a snapshot of the current runqueue time of this cpu
3658   * with the per-cpu cid value, allowing to estimate how recently it was used.
3659   */
mm_cid_snapshot_time(struct rq * rq,struct mm_struct * mm)3660  static inline void mm_cid_snapshot_time(struct rq *rq, struct mm_struct *mm)
3661  {
3662  	struct mm_cid *pcpu_cid = per_cpu_ptr(mm->pcpu_cid, cpu_of(rq));
3663  
3664  	lockdep_assert_rq_held(rq);
3665  	WRITE_ONCE(pcpu_cid->time, rq->clock);
3666  }
3667  
__mm_cid_get(struct rq * rq,struct mm_struct * mm)3668  static inline int __mm_cid_get(struct rq *rq, struct mm_struct *mm)
3669  {
3670  	int cid;
3671  
3672  	/*
3673  	 * All allocations (even those using the cid_lock) are lock-free. If
3674  	 * use_cid_lock is set, hold the cid_lock to perform cid allocation to
3675  	 * guarantee forward progress.
3676  	 */
3677  	if (!READ_ONCE(use_cid_lock)) {
3678  		cid = __mm_cid_try_get(mm);
3679  		if (cid >= 0)
3680  			goto end;
3681  		raw_spin_lock(&cid_lock);
3682  	} else {
3683  		raw_spin_lock(&cid_lock);
3684  		cid = __mm_cid_try_get(mm);
3685  		if (cid >= 0)
3686  			goto unlock;
3687  	}
3688  
3689  	/*
3690  	 * cid concurrently allocated. Retry while forcing following
3691  	 * allocations to use the cid_lock to ensure forward progress.
3692  	 */
3693  	WRITE_ONCE(use_cid_lock, 1);
3694  	/*
3695  	 * Set use_cid_lock before allocation. Only care about program order
3696  	 * because this is only required for forward progress.
3697  	 */
3698  	barrier();
3699  	/*
3700  	 * Retry until it succeeds. It is guaranteed to eventually succeed once
3701  	 * all newcoming allocations observe the use_cid_lock flag set.
3702  	 */
3703  	do {
3704  		cid = __mm_cid_try_get(mm);
3705  		cpu_relax();
3706  	} while (cid < 0);
3707  	/*
3708  	 * Allocate before clearing use_cid_lock. Only care about
3709  	 * program order because this is for forward progress.
3710  	 */
3711  	barrier();
3712  	WRITE_ONCE(use_cid_lock, 0);
3713  unlock:
3714  	raw_spin_unlock(&cid_lock);
3715  end:
3716  	mm_cid_snapshot_time(rq, mm);
3717  
3718  	return cid;
3719  }
3720  
mm_cid_get(struct rq * rq,struct mm_struct * mm)3721  static inline int mm_cid_get(struct rq *rq, struct mm_struct *mm)
3722  {
3723  	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3724  	struct cpumask *cpumask;
3725  	int cid;
3726  
3727  	lockdep_assert_rq_held(rq);
3728  	cpumask = mm_cidmask(mm);
3729  	cid = __this_cpu_read(pcpu_cid->cid);
3730  	if (mm_cid_is_valid(cid)) {
3731  		mm_cid_snapshot_time(rq, mm);
3732  		return cid;
3733  	}
3734  	if (mm_cid_is_lazy_put(cid)) {
3735  		if (try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET))
3736  			__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3737  	}
3738  	cid = __mm_cid_get(rq, mm);
3739  	__this_cpu_write(pcpu_cid->cid, cid);
3740  
3741  	return cid;
3742  }
3743  
switch_mm_cid(struct rq * rq,struct task_struct * prev,struct task_struct * next)3744  static inline void switch_mm_cid(struct rq *rq,
3745  				 struct task_struct *prev,
3746  				 struct task_struct *next)
3747  {
3748  	/*
3749  	 * Provide a memory barrier between rq->curr store and load of
3750  	 * {prev,next}->mm->pcpu_cid[cpu] on rq->curr->mm transition.
3751  	 *
3752  	 * Should be adapted if context_switch() is modified.
3753  	 */
3754  	if (!next->mm) {                                // to kernel
3755  		/*
3756  		 * user -> kernel transition does not guarantee a barrier, but
3757  		 * we can use the fact that it performs an atomic operation in
3758  		 * mmgrab().
3759  		 */
3760  		if (prev->mm)                           // from user
3761  			smp_mb__after_mmgrab();
3762  		/*
3763  		 * kernel -> kernel transition does not change rq->curr->mm
3764  		 * state. It stays NULL.
3765  		 */
3766  	} else {                                        // to user
3767  		/*
3768  		 * kernel -> user transition does not provide a barrier
3769  		 * between rq->curr store and load of {prev,next}->mm->pcpu_cid[cpu].
3770  		 * Provide it here.
3771  		 */
3772  		if (!prev->mm) {                        // from kernel
3773  			smp_mb();
3774  		} else {				// from user
3775  			/*
3776  			 * user->user transition relies on an implicit
3777  			 * memory barrier in switch_mm() when
3778  			 * current->mm changes. If the architecture
3779  			 * switch_mm() does not have an implicit memory
3780  			 * barrier, it is emitted here.  If current->mm
3781  			 * is unchanged, no barrier is needed.
3782  			 */
3783  			smp_mb__after_switch_mm();
3784  		}
3785  	}
3786  	if (prev->mm_cid_active) {
3787  		mm_cid_snapshot_time(rq, prev->mm);
3788  		mm_cid_put_lazy(prev);
3789  		prev->mm_cid = -1;
3790  	}
3791  	if (next->mm_cid_active)
3792  		next->last_mm_cid = next->mm_cid = mm_cid_get(rq, next->mm);
3793  }
3794  
3795  #else /* !CONFIG_SCHED_MM_CID: */
switch_mm_cid(struct rq * rq,struct task_struct * prev,struct task_struct * next)3796  static inline void switch_mm_cid(struct rq *rq, struct task_struct *prev, struct task_struct *next) { }
sched_mm_cid_migrate_from(struct task_struct * t)3797  static inline void sched_mm_cid_migrate_from(struct task_struct *t) { }
sched_mm_cid_migrate_to(struct rq * dst_rq,struct task_struct * t)3798  static inline void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t) { }
task_tick_mm_cid(struct rq * rq,struct task_struct * curr)3799  static inline void task_tick_mm_cid(struct rq *rq, struct task_struct *curr) { }
init_sched_mm_cid(struct task_struct * t)3800  static inline void init_sched_mm_cid(struct task_struct *t) { }
3801  #endif /* !CONFIG_SCHED_MM_CID */
3802  
3803  extern u64 avg_vruntime(struct cfs_rq *cfs_rq);
3804  extern int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se);
3805  
3806  #ifdef CONFIG_RT_MUTEXES
3807  
__rt_effective_prio(struct task_struct * pi_task,int prio)3808  static inline int __rt_effective_prio(struct task_struct *pi_task, int prio)
3809  {
3810  	if (pi_task)
3811  		prio = min(prio, pi_task->prio);
3812  
3813  	return prio;
3814  }
3815  
rt_effective_prio(struct task_struct * p,int prio)3816  static inline int rt_effective_prio(struct task_struct *p, int prio)
3817  {
3818  	struct task_struct *pi_task = rt_mutex_get_top_task(p);
3819  
3820  	return __rt_effective_prio(pi_task, prio);
3821  }
3822  
3823  #else /* !CONFIG_RT_MUTEXES: */
3824  
rt_effective_prio(struct task_struct * p,int prio)3825  static inline int rt_effective_prio(struct task_struct *p, int prio)
3826  {
3827  	return prio;
3828  }
3829  
3830  #endif /* !CONFIG_RT_MUTEXES */
3831  
3832  extern int __sched_setscheduler(struct task_struct *p, const struct sched_attr *attr, bool user, bool pi);
3833  extern int __sched_setaffinity(struct task_struct *p, struct affinity_context *ctx);
3834  extern const struct sched_class *__setscheduler_class(int policy, int prio);
3835  extern void set_load_weight(struct task_struct *p, bool update_load);
3836  extern void enqueue_task(struct rq *rq, struct task_struct *p, int flags);
3837  extern bool dequeue_task(struct rq *rq, struct task_struct *p, int flags);
3838  
3839  extern void check_class_changing(struct rq *rq, struct task_struct *p,
3840  				 const struct sched_class *prev_class);
3841  extern void check_class_changed(struct rq *rq, struct task_struct *p,
3842  				const struct sched_class *prev_class,
3843  				int oldprio);
3844  
3845  #ifdef CONFIG_SMP
3846  extern struct balance_callback *splice_balance_callbacks(struct rq *rq);
3847  extern void balance_callbacks(struct rq *rq, struct balance_callback *head);
3848  #else
3849  
splice_balance_callbacks(struct rq * rq)3850  static inline struct balance_callback *splice_balance_callbacks(struct rq *rq)
3851  {
3852  	return NULL;
3853  }
3854  
balance_callbacks(struct rq * rq,struct balance_callback * head)3855  static inline void balance_callbacks(struct rq *rq, struct balance_callback *head)
3856  {
3857  }
3858  
3859  #endif
3860  
3861  #ifdef CONFIG_SCHED_CLASS_EXT
3862  /*
3863   * Used by SCX in the enable/disable paths to move tasks between sched_classes
3864   * and establish invariants.
3865   */
3866  struct sched_enq_and_set_ctx {
3867  	struct task_struct	*p;
3868  	int			queue_flags;
3869  	bool			queued;
3870  	bool			running;
3871  };
3872  
3873  void sched_deq_and_put_task(struct task_struct *p, int queue_flags,
3874  			    struct sched_enq_and_set_ctx *ctx);
3875  void sched_enq_and_set_task(struct sched_enq_and_set_ctx *ctx);
3876  
3877  #endif /* CONFIG_SCHED_CLASS_EXT */
3878  
3879  #include "ext.h"
3880  
3881  #endif /* _KERNEL_SCHED_SCHED_H */
3882