xref: /linux/kernel/sched/sched.h (revision 5db91545)
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_KEEP		= 1 << 2, /* balance decided to keep current */
755 	SCX_RQ_BYPASSING	= 1 << 3,
756 
757 	SCX_RQ_IN_WAKEUP	= 1 << 16,
758 	SCX_RQ_IN_BALANCE	= 1 << 17,
759 };
760 
761 struct scx_rq {
762 	struct scx_dispatch_q	local_dsq;
763 	struct list_head	runnable_list;		/* runnable tasks on this rq */
764 	struct list_head	ddsp_deferred_locals;	/* deferred ddsps from enq */
765 	unsigned long		ops_qseq;
766 	u64			extra_enq_flags;	/* see move_task_to_local_dsq() */
767 	u32			nr_running;
768 	u32			flags;
769 	u32			cpuperf_target;		/* [0, SCHED_CAPACITY_SCALE] */
770 	bool			cpu_released;
771 	cpumask_var_t		cpus_to_kick;
772 	cpumask_var_t		cpus_to_kick_if_idle;
773 	cpumask_var_t		cpus_to_preempt;
774 	cpumask_var_t		cpus_to_wait;
775 	unsigned long		pnt_seq;
776 	struct balance_callback	deferred_bal_cb;
777 	struct irq_work		deferred_irq_work;
778 	struct irq_work		kick_cpus_irq_work;
779 };
780 #endif /* CONFIG_SCHED_CLASS_EXT */
781 
rt_bandwidth_enabled(void)782 static inline int rt_bandwidth_enabled(void)
783 {
784 	return sysctl_sched_rt_runtime >= 0;
785 }
786 
787 /* RT IPI pull logic requires IRQ_WORK */
788 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
789 # define HAVE_RT_PUSH_IPI
790 #endif
791 
792 /* Real-Time classes' related field in a runqueue: */
793 struct rt_rq {
794 	struct rt_prio_array	active;
795 	unsigned int		rt_nr_running;
796 	unsigned int		rr_nr_running;
797 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
798 	struct {
799 		int		curr; /* highest queued rt task prio */
800 #ifdef CONFIG_SMP
801 		int		next; /* next highest */
802 #endif
803 	} highest_prio;
804 #endif
805 #ifdef CONFIG_SMP
806 	bool			overloaded;
807 	struct plist_head	pushable_tasks;
808 
809 #endif /* CONFIG_SMP */
810 	int			rt_queued;
811 
812 #ifdef CONFIG_RT_GROUP_SCHED
813 	int			rt_throttled;
814 	u64			rt_time;
815 	u64			rt_runtime;
816 	/* Nests inside the rq lock: */
817 	raw_spinlock_t		rt_runtime_lock;
818 
819 	unsigned int		rt_nr_boosted;
820 
821 	struct rq		*rq;
822 	struct task_group	*tg;
823 #endif
824 };
825 
rt_rq_is_runnable(struct rt_rq * rt_rq)826 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
827 {
828 	return rt_rq->rt_queued && rt_rq->rt_nr_running;
829 }
830 
831 /* Deadline class' related fields in a runqueue */
832 struct dl_rq {
833 	/* runqueue is an rbtree, ordered by deadline */
834 	struct rb_root_cached	root;
835 
836 	unsigned int		dl_nr_running;
837 
838 #ifdef CONFIG_SMP
839 	/*
840 	 * Deadline values of the currently executing and the
841 	 * earliest ready task on this rq. Caching these facilitates
842 	 * the decision whether or not a ready but not running task
843 	 * should migrate somewhere else.
844 	 */
845 	struct {
846 		u64		curr;
847 		u64		next;
848 	} earliest_dl;
849 
850 	bool			overloaded;
851 
852 	/*
853 	 * Tasks on this rq that can be pushed away. They are kept in
854 	 * an rb-tree, ordered by tasks' deadlines, with caching
855 	 * of the leftmost (earliest deadline) element.
856 	 */
857 	struct rb_root_cached	pushable_dl_tasks_root;
858 #else
859 	struct dl_bw		dl_bw;
860 #endif
861 	/*
862 	 * "Active utilization" for this runqueue: increased when a
863 	 * task wakes up (becomes TASK_RUNNING) and decreased when a
864 	 * task blocks
865 	 */
866 	u64			running_bw;
867 
868 	/*
869 	 * Utilization of the tasks "assigned" to this runqueue (including
870 	 * the tasks that are in runqueue and the tasks that executed on this
871 	 * CPU and blocked). Increased when a task moves to this runqueue, and
872 	 * decreased when the task moves away (migrates, changes scheduling
873 	 * policy, or terminates).
874 	 * This is needed to compute the "inactive utilization" for the
875 	 * runqueue (inactive utilization = this_bw - running_bw).
876 	 */
877 	u64			this_bw;
878 	u64			extra_bw;
879 
880 	/*
881 	 * Maximum available bandwidth for reclaiming by SCHED_FLAG_RECLAIM
882 	 * tasks of this rq. Used in calculation of reclaimable bandwidth(GRUB).
883 	 */
884 	u64			max_bw;
885 
886 	/*
887 	 * Inverse of the fraction of CPU utilization that can be reclaimed
888 	 * by the GRUB algorithm.
889 	 */
890 	u64			bw_ratio;
891 };
892 
893 #ifdef CONFIG_FAIR_GROUP_SCHED
894 
895 /* An entity is a task if it doesn't "own" a runqueue */
896 #define entity_is_task(se)	(!se->my_q)
897 
se_update_runnable(struct sched_entity * se)898 static inline void se_update_runnable(struct sched_entity *se)
899 {
900 	if (!entity_is_task(se))
901 		se->runnable_weight = se->my_q->h_nr_running;
902 }
903 
se_runnable(struct sched_entity * se)904 static inline long se_runnable(struct sched_entity *se)
905 {
906 	if (se->sched_delayed)
907 		return false;
908 
909 	if (entity_is_task(se))
910 		return !!se->on_rq;
911 	else
912 		return se->runnable_weight;
913 }
914 
915 #else /* !CONFIG_FAIR_GROUP_SCHED: */
916 
917 #define entity_is_task(se)	1
918 
se_update_runnable(struct sched_entity * se)919 static inline void se_update_runnable(struct sched_entity *se) { }
920 
se_runnable(struct sched_entity * se)921 static inline long se_runnable(struct sched_entity *se)
922 {
923 	if (se->sched_delayed)
924 		return false;
925 
926 	return !!se->on_rq;
927 }
928 
929 #endif /* !CONFIG_FAIR_GROUP_SCHED */
930 
931 #ifdef CONFIG_SMP
932 /*
933  * XXX we want to get rid of these helpers and use the full load resolution.
934  */
se_weight(struct sched_entity * se)935 static inline long se_weight(struct sched_entity *se)
936 {
937 	return scale_load_down(se->load.weight);
938 }
939 
940 
sched_asym_prefer(int a,int b)941 static inline bool sched_asym_prefer(int a, int b)
942 {
943 	return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
944 }
945 
946 struct perf_domain {
947 	struct em_perf_domain *em_pd;
948 	struct perf_domain *next;
949 	struct rcu_head rcu;
950 };
951 
952 /*
953  * We add the notion of a root-domain which will be used to define per-domain
954  * variables. Each exclusive cpuset essentially defines an island domain by
955  * fully partitioning the member CPUs from any other cpuset. Whenever a new
956  * exclusive cpuset is created, we also create and attach a new root-domain
957  * object.
958  *
959  */
960 struct root_domain {
961 	atomic_t		refcount;
962 	atomic_t		rto_count;
963 	struct rcu_head		rcu;
964 	cpumask_var_t		span;
965 	cpumask_var_t		online;
966 
967 	/*
968 	 * Indicate pullable load on at least one CPU, e.g:
969 	 * - More than one runnable task
970 	 * - Running task is misfit
971 	 */
972 	bool			overloaded;
973 
974 	/* Indicate one or more CPUs over-utilized (tipping point) */
975 	bool			overutilized;
976 
977 	/*
978 	 * The bit corresponding to a CPU gets set here if such CPU has more
979 	 * than one runnable -deadline task (as it is below for RT tasks).
980 	 */
981 	cpumask_var_t		dlo_mask;
982 	atomic_t		dlo_count;
983 	struct dl_bw		dl_bw;
984 	struct cpudl		cpudl;
985 
986 	/*
987 	 * Indicate whether a root_domain's dl_bw has been checked or
988 	 * updated. It's monotonously increasing value.
989 	 *
990 	 * Also, some corner cases, like 'wrap around' is dangerous, but given
991 	 * that u64 is 'big enough'. So that shouldn't be a concern.
992 	 */
993 	u64 visit_gen;
994 
995 #ifdef HAVE_RT_PUSH_IPI
996 	/*
997 	 * For IPI pull requests, loop across the rto_mask.
998 	 */
999 	struct irq_work		rto_push_work;
1000 	raw_spinlock_t		rto_lock;
1001 	/* These are only updated and read within rto_lock */
1002 	int			rto_loop;
1003 	int			rto_cpu;
1004 	/* These atomics are updated outside of a lock */
1005 	atomic_t		rto_loop_next;
1006 	atomic_t		rto_loop_start;
1007 #endif
1008 	/*
1009 	 * The "RT overload" flag: it gets set if a CPU has more than
1010 	 * one runnable RT task.
1011 	 */
1012 	cpumask_var_t		rto_mask;
1013 	struct cpupri		cpupri;
1014 
1015 	/*
1016 	 * NULL-terminated list of performance domains intersecting with the
1017 	 * CPUs of the rd. Protected by RCU.
1018 	 */
1019 	struct perf_domain __rcu *pd;
1020 };
1021 
1022 extern void init_defrootdomain(void);
1023 extern int sched_init_domains(const struct cpumask *cpu_map);
1024 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
1025 extern void sched_get_rd(struct root_domain *rd);
1026 extern void sched_put_rd(struct root_domain *rd);
1027 
get_rd_overloaded(struct root_domain * rd)1028 static inline int get_rd_overloaded(struct root_domain *rd)
1029 {
1030 	return READ_ONCE(rd->overloaded);
1031 }
1032 
set_rd_overloaded(struct root_domain * rd,int status)1033 static inline void set_rd_overloaded(struct root_domain *rd, int status)
1034 {
1035 	if (get_rd_overloaded(rd) != status)
1036 		WRITE_ONCE(rd->overloaded, status);
1037 }
1038 
1039 #ifdef HAVE_RT_PUSH_IPI
1040 extern void rto_push_irq_work_func(struct irq_work *work);
1041 #endif
1042 #endif /* CONFIG_SMP */
1043 
1044 #ifdef CONFIG_UCLAMP_TASK
1045 /*
1046  * struct uclamp_bucket - Utilization clamp bucket
1047  * @value: utilization clamp value for tasks on this clamp bucket
1048  * @tasks: number of RUNNABLE tasks on this clamp bucket
1049  *
1050  * Keep track of how many tasks are RUNNABLE for a given utilization
1051  * clamp value.
1052  */
1053 struct uclamp_bucket {
1054 	unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
1055 	unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
1056 };
1057 
1058 /*
1059  * struct uclamp_rq - rq's utilization clamp
1060  * @value: currently active clamp values for a rq
1061  * @bucket: utilization clamp buckets affecting a rq
1062  *
1063  * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
1064  * A clamp value is affecting a rq when there is at least one task RUNNABLE
1065  * (or actually running) with that value.
1066  *
1067  * There are up to UCLAMP_CNT possible different clamp values, currently there
1068  * are only two: minimum utilization and maximum utilization.
1069  *
1070  * All utilization clamping values are MAX aggregated, since:
1071  * - for util_min: we want to run the CPU at least at the max of the minimum
1072  *   utilization required by its currently RUNNABLE tasks.
1073  * - for util_max: we want to allow the CPU to run up to the max of the
1074  *   maximum utilization allowed by its currently RUNNABLE tasks.
1075  *
1076  * Since on each system we expect only a limited number of different
1077  * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
1078  * the metrics required to compute all the per-rq utilization clamp values.
1079  */
1080 struct uclamp_rq {
1081 	unsigned int value;
1082 	struct uclamp_bucket bucket[UCLAMP_BUCKETS];
1083 };
1084 
1085 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
1086 #endif /* CONFIG_UCLAMP_TASK */
1087 
1088 /*
1089  * This is the main, per-CPU runqueue data structure.
1090  *
1091  * Locking rule: those places that want to lock multiple runqueues
1092  * (such as the load balancing or the thread migration code), lock
1093  * acquire operations must be ordered by ascending &runqueue.
1094  */
1095 struct rq {
1096 	/* runqueue lock: */
1097 	raw_spinlock_t		__lock;
1098 
1099 	unsigned int		nr_running;
1100 #ifdef CONFIG_NUMA_BALANCING
1101 	unsigned int		nr_numa_running;
1102 	unsigned int		nr_preferred_running;
1103 	unsigned int		numa_migrate_on;
1104 #endif
1105 #ifdef CONFIG_NO_HZ_COMMON
1106 #ifdef CONFIG_SMP
1107 	unsigned long		last_blocked_load_update_tick;
1108 	unsigned int		has_blocked_load;
1109 	call_single_data_t	nohz_csd;
1110 #endif /* CONFIG_SMP */
1111 	unsigned int		nohz_tick_stopped;
1112 	atomic_t		nohz_flags;
1113 #endif /* CONFIG_NO_HZ_COMMON */
1114 
1115 #ifdef CONFIG_SMP
1116 	unsigned int		ttwu_pending;
1117 #endif
1118 	u64			nr_switches;
1119 
1120 #ifdef CONFIG_UCLAMP_TASK
1121 	/* Utilization clamp values based on CPU's RUNNABLE tasks */
1122 	struct uclamp_rq	uclamp[UCLAMP_CNT] ____cacheline_aligned;
1123 	unsigned int		uclamp_flags;
1124 #define UCLAMP_FLAG_IDLE 0x01
1125 #endif
1126 
1127 	struct cfs_rq		cfs;
1128 	struct rt_rq		rt;
1129 	struct dl_rq		dl;
1130 #ifdef CONFIG_SCHED_CLASS_EXT
1131 	struct scx_rq		scx;
1132 #endif
1133 
1134 	struct sched_dl_entity	fair_server;
1135 
1136 #ifdef CONFIG_FAIR_GROUP_SCHED
1137 	/* list of leaf cfs_rq on this CPU: */
1138 	struct list_head	leaf_cfs_rq_list;
1139 	struct list_head	*tmp_alone_branch;
1140 #endif /* CONFIG_FAIR_GROUP_SCHED */
1141 
1142 	/*
1143 	 * This is part of a global counter where only the total sum
1144 	 * over all CPUs matters. A task can increase this counter on
1145 	 * one CPU and if it got migrated afterwards it may decrease
1146 	 * it on another CPU. Always updated under the runqueue lock:
1147 	 */
1148 	unsigned int		nr_uninterruptible;
1149 
1150 	struct task_struct __rcu	*curr;
1151 	struct sched_dl_entity	*dl_server;
1152 	struct task_struct	*idle;
1153 	struct task_struct	*stop;
1154 	unsigned long		next_balance;
1155 	struct mm_struct	*prev_mm;
1156 
1157 	unsigned int		clock_update_flags;
1158 	u64			clock;
1159 	/* Ensure that all clocks are in the same cache line */
1160 	u64			clock_task ____cacheline_aligned;
1161 	u64			clock_pelt;
1162 	unsigned long		lost_idle_time;
1163 	u64			clock_pelt_idle;
1164 	u64			clock_idle;
1165 #ifndef CONFIG_64BIT
1166 	u64			clock_pelt_idle_copy;
1167 	u64			clock_idle_copy;
1168 #endif
1169 
1170 	atomic_t		nr_iowait;
1171 
1172 #ifdef CONFIG_SCHED_DEBUG
1173 	u64 last_seen_need_resched_ns;
1174 	int ticks_without_resched;
1175 #endif
1176 
1177 #ifdef CONFIG_MEMBARRIER
1178 	int membarrier_state;
1179 #endif
1180 
1181 #ifdef CONFIG_SMP
1182 	struct root_domain		*rd;
1183 	struct sched_domain __rcu	*sd;
1184 
1185 	unsigned long		cpu_capacity;
1186 
1187 	struct balance_callback *balance_callback;
1188 
1189 	unsigned char		nohz_idle_balance;
1190 	unsigned char		idle_balance;
1191 
1192 	unsigned long		misfit_task_load;
1193 
1194 	/* For active balancing */
1195 	int			active_balance;
1196 	int			push_cpu;
1197 	struct cpu_stop_work	active_balance_work;
1198 
1199 	/* CPU of this runqueue: */
1200 	int			cpu;
1201 	int			online;
1202 
1203 	struct list_head cfs_tasks;
1204 
1205 	struct sched_avg	avg_rt;
1206 	struct sched_avg	avg_dl;
1207 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1208 	struct sched_avg	avg_irq;
1209 #endif
1210 #ifdef CONFIG_SCHED_HW_PRESSURE
1211 	struct sched_avg	avg_hw;
1212 #endif
1213 	u64			idle_stamp;
1214 	u64			avg_idle;
1215 
1216 	/* This is used to determine avg_idle's max value */
1217 	u64			max_idle_balance_cost;
1218 
1219 #ifdef CONFIG_HOTPLUG_CPU
1220 	struct rcuwait		hotplug_wait;
1221 #endif
1222 #endif /* CONFIG_SMP */
1223 
1224 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1225 	u64			prev_irq_time;
1226 	u64			psi_irq_time;
1227 #endif
1228 #ifdef CONFIG_PARAVIRT
1229 	u64			prev_steal_time;
1230 #endif
1231 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1232 	u64			prev_steal_time_rq;
1233 #endif
1234 
1235 	/* calc_load related fields */
1236 	unsigned long		calc_load_update;
1237 	long			calc_load_active;
1238 
1239 #ifdef CONFIG_SCHED_HRTICK
1240 #ifdef CONFIG_SMP
1241 	call_single_data_t	hrtick_csd;
1242 #endif
1243 	struct hrtimer		hrtick_timer;
1244 	ktime_t			hrtick_time;
1245 #endif
1246 
1247 #ifdef CONFIG_SCHEDSTATS
1248 	/* latency stats */
1249 	struct sched_info	rq_sched_info;
1250 	unsigned long long	rq_cpu_time;
1251 
1252 	/* sys_sched_yield() stats */
1253 	unsigned int		yld_count;
1254 
1255 	/* schedule() stats */
1256 	unsigned int		sched_count;
1257 	unsigned int		sched_goidle;
1258 
1259 	/* try_to_wake_up() stats */
1260 	unsigned int		ttwu_count;
1261 	unsigned int		ttwu_local;
1262 #endif
1263 
1264 #ifdef CONFIG_CPU_IDLE
1265 	/* Must be inspected within a RCU lock section */
1266 	struct cpuidle_state	*idle_state;
1267 #endif
1268 
1269 #ifdef CONFIG_SMP
1270 	unsigned int		nr_pinned;
1271 #endif
1272 	unsigned int		push_busy;
1273 	struct cpu_stop_work	push_work;
1274 
1275 #ifdef CONFIG_SCHED_CORE
1276 	/* per rq */
1277 	struct rq		*core;
1278 	struct task_struct	*core_pick;
1279 	struct sched_dl_entity	*core_dl_server;
1280 	unsigned int		core_enabled;
1281 	unsigned int		core_sched_seq;
1282 	struct rb_root		core_tree;
1283 
1284 	/* shared state -- careful with sched_core_cpu_deactivate() */
1285 	unsigned int		core_task_seq;
1286 	unsigned int		core_pick_seq;
1287 	unsigned long		core_cookie;
1288 	unsigned int		core_forceidle_count;
1289 	unsigned int		core_forceidle_seq;
1290 	unsigned int		core_forceidle_occupation;
1291 	u64			core_forceidle_start;
1292 #endif
1293 
1294 	/* Scratch cpumask to be temporarily used under rq_lock */
1295 	cpumask_var_t		scratch_mask;
1296 
1297 #if defined(CONFIG_CFS_BANDWIDTH) && defined(CONFIG_SMP)
1298 	call_single_data_t	cfsb_csd;
1299 	struct list_head	cfsb_csd_list;
1300 #endif
1301 };
1302 
1303 #ifdef CONFIG_FAIR_GROUP_SCHED
1304 
1305 /* CPU runqueue to which this cfs_rq is attached */
rq_of(struct cfs_rq * cfs_rq)1306 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1307 {
1308 	return cfs_rq->rq;
1309 }
1310 
1311 #else
1312 
rq_of(struct cfs_rq * cfs_rq)1313 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1314 {
1315 	return container_of(cfs_rq, struct rq, cfs);
1316 }
1317 #endif
1318 
cpu_of(struct rq * rq)1319 static inline int cpu_of(struct rq *rq)
1320 {
1321 #ifdef CONFIG_SMP
1322 	return rq->cpu;
1323 #else
1324 	return 0;
1325 #endif
1326 }
1327 
1328 #define MDF_PUSH		0x01
1329 
is_migration_disabled(struct task_struct * p)1330 static inline bool is_migration_disabled(struct task_struct *p)
1331 {
1332 #ifdef CONFIG_SMP
1333 	return p->migration_disabled;
1334 #else
1335 	return false;
1336 #endif
1337 }
1338 
1339 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1340 
1341 #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
1342 #define this_rq()		this_cpu_ptr(&runqueues)
1343 #define task_rq(p)		cpu_rq(task_cpu(p))
1344 #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
1345 #define raw_rq()		raw_cpu_ptr(&runqueues)
1346 
1347 #ifdef CONFIG_SCHED_CORE
1348 static inline struct cpumask *sched_group_span(struct sched_group *sg);
1349 
1350 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled);
1351 
sched_core_enabled(struct rq * rq)1352 static inline bool sched_core_enabled(struct rq *rq)
1353 {
1354 	return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled;
1355 }
1356 
sched_core_disabled(void)1357 static inline bool sched_core_disabled(void)
1358 {
1359 	return !static_branch_unlikely(&__sched_core_enabled);
1360 }
1361 
1362 /*
1363  * Be careful with this function; not for general use. The return value isn't
1364  * stable unless you actually hold a relevant rq->__lock.
1365  */
rq_lockp(struct rq * rq)1366 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1367 {
1368 	if (sched_core_enabled(rq))
1369 		return &rq->core->__lock;
1370 
1371 	return &rq->__lock;
1372 }
1373 
__rq_lockp(struct rq * rq)1374 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1375 {
1376 	if (rq->core_enabled)
1377 		return &rq->core->__lock;
1378 
1379 	return &rq->__lock;
1380 }
1381 
1382 extern bool
1383 cfs_prio_less(const struct task_struct *a, const struct task_struct *b, bool fi);
1384 
1385 extern void task_vruntime_update(struct rq *rq, struct task_struct *p, bool in_fi);
1386 
1387 /*
1388  * Helpers to check if the CPU's core cookie matches with the task's cookie
1389  * when core scheduling is enabled.
1390  * A special case is that the task's cookie always matches with CPU's core
1391  * cookie if the CPU is in an idle core.
1392  */
sched_cpu_cookie_match(struct rq * rq,struct task_struct * p)1393 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1394 {
1395 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1396 	if (!sched_core_enabled(rq))
1397 		return true;
1398 
1399 	return rq->core->core_cookie == p->core_cookie;
1400 }
1401 
sched_core_cookie_match(struct rq * rq,struct task_struct * p)1402 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1403 {
1404 	bool idle_core = true;
1405 	int cpu;
1406 
1407 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1408 	if (!sched_core_enabled(rq))
1409 		return true;
1410 
1411 	for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) {
1412 		if (!available_idle_cpu(cpu)) {
1413 			idle_core = false;
1414 			break;
1415 		}
1416 	}
1417 
1418 	/*
1419 	 * A CPU in an idle core is always the best choice for tasks with
1420 	 * cookies.
1421 	 */
1422 	return idle_core || rq->core->core_cookie == p->core_cookie;
1423 }
1424 
sched_group_cookie_match(struct rq * rq,struct task_struct * p,struct sched_group * group)1425 static inline bool sched_group_cookie_match(struct rq *rq,
1426 					    struct task_struct *p,
1427 					    struct sched_group *group)
1428 {
1429 	int cpu;
1430 
1431 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1432 	if (!sched_core_enabled(rq))
1433 		return true;
1434 
1435 	for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
1436 		if (sched_core_cookie_match(cpu_rq(cpu), p))
1437 			return true;
1438 	}
1439 	return false;
1440 }
1441 
sched_core_enqueued(struct task_struct * p)1442 static inline bool sched_core_enqueued(struct task_struct *p)
1443 {
1444 	return !RB_EMPTY_NODE(&p->core_node);
1445 }
1446 
1447 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p);
1448 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags);
1449 
1450 extern void sched_core_get(void);
1451 extern void sched_core_put(void);
1452 
1453 #else /* !CONFIG_SCHED_CORE: */
1454 
sched_core_enabled(struct rq * rq)1455 static inline bool sched_core_enabled(struct rq *rq)
1456 {
1457 	return false;
1458 }
1459 
sched_core_disabled(void)1460 static inline bool sched_core_disabled(void)
1461 {
1462 	return true;
1463 }
1464 
rq_lockp(struct rq * rq)1465 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1466 {
1467 	return &rq->__lock;
1468 }
1469 
__rq_lockp(struct rq * rq)1470 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1471 {
1472 	return &rq->__lock;
1473 }
1474 
sched_cpu_cookie_match(struct rq * rq,struct task_struct * p)1475 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1476 {
1477 	return true;
1478 }
1479 
sched_core_cookie_match(struct rq * rq,struct task_struct * p)1480 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1481 {
1482 	return true;
1483 }
1484 
sched_group_cookie_match(struct rq * rq,struct task_struct * p,struct sched_group * group)1485 static inline bool sched_group_cookie_match(struct rq *rq,
1486 					    struct task_struct *p,
1487 					    struct sched_group *group)
1488 {
1489 	return true;
1490 }
1491 
1492 #endif /* !CONFIG_SCHED_CORE */
1493 
lockdep_assert_rq_held(struct rq * rq)1494 static inline void lockdep_assert_rq_held(struct rq *rq)
1495 {
1496 	lockdep_assert_held(__rq_lockp(rq));
1497 }
1498 
1499 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass);
1500 extern bool raw_spin_rq_trylock(struct rq *rq);
1501 extern void raw_spin_rq_unlock(struct rq *rq);
1502 
raw_spin_rq_lock(struct rq * rq)1503 static inline void raw_spin_rq_lock(struct rq *rq)
1504 {
1505 	raw_spin_rq_lock_nested(rq, 0);
1506 }
1507 
raw_spin_rq_lock_irq(struct rq * rq)1508 static inline void raw_spin_rq_lock_irq(struct rq *rq)
1509 {
1510 	local_irq_disable();
1511 	raw_spin_rq_lock(rq);
1512 }
1513 
raw_spin_rq_unlock_irq(struct rq * rq)1514 static inline void raw_spin_rq_unlock_irq(struct rq *rq)
1515 {
1516 	raw_spin_rq_unlock(rq);
1517 	local_irq_enable();
1518 }
1519 
_raw_spin_rq_lock_irqsave(struct rq * rq)1520 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq)
1521 {
1522 	unsigned long flags;
1523 
1524 	local_irq_save(flags);
1525 	raw_spin_rq_lock(rq);
1526 
1527 	return flags;
1528 }
1529 
raw_spin_rq_unlock_irqrestore(struct rq * rq,unsigned long flags)1530 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags)
1531 {
1532 	raw_spin_rq_unlock(rq);
1533 	local_irq_restore(flags);
1534 }
1535 
1536 #define raw_spin_rq_lock_irqsave(rq, flags)	\
1537 do {						\
1538 	flags = _raw_spin_rq_lock_irqsave(rq);	\
1539 } while (0)
1540 
1541 #ifdef CONFIG_SCHED_SMT
1542 extern void __update_idle_core(struct rq *rq);
1543 
update_idle_core(struct rq * rq)1544 static inline void update_idle_core(struct rq *rq)
1545 {
1546 	if (static_branch_unlikely(&sched_smt_present))
1547 		__update_idle_core(rq);
1548 }
1549 
1550 #else
update_idle_core(struct rq * rq)1551 static inline void update_idle_core(struct rq *rq) { }
1552 #endif
1553 
1554 #ifdef CONFIG_FAIR_GROUP_SCHED
1555 
task_of(struct sched_entity * se)1556 static inline struct task_struct *task_of(struct sched_entity *se)
1557 {
1558 	SCHED_WARN_ON(!entity_is_task(se));
1559 	return container_of(se, struct task_struct, se);
1560 }
1561 
task_cfs_rq(struct task_struct * p)1562 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1563 {
1564 	return p->se.cfs_rq;
1565 }
1566 
1567 /* runqueue on which this entity is (to be) queued */
cfs_rq_of(const struct sched_entity * se)1568 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1569 {
1570 	return se->cfs_rq;
1571 }
1572 
1573 /* runqueue "owned" by this group */
group_cfs_rq(struct sched_entity * grp)1574 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1575 {
1576 	return grp->my_q;
1577 }
1578 
1579 #else /* !CONFIG_FAIR_GROUP_SCHED: */
1580 
1581 #define task_of(_se)		container_of(_se, struct task_struct, se)
1582 
task_cfs_rq(const struct task_struct * p)1583 static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p)
1584 {
1585 	return &task_rq(p)->cfs;
1586 }
1587 
cfs_rq_of(const struct sched_entity * se)1588 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1589 {
1590 	const struct task_struct *p = task_of(se);
1591 	struct rq *rq = task_rq(p);
1592 
1593 	return &rq->cfs;
1594 }
1595 
1596 /* runqueue "owned" by this group */
group_cfs_rq(struct sched_entity * grp)1597 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1598 {
1599 	return NULL;
1600 }
1601 
1602 #endif /* !CONFIG_FAIR_GROUP_SCHED */
1603 
1604 extern void update_rq_clock(struct rq *rq);
1605 
1606 /*
1607  * rq::clock_update_flags bits
1608  *
1609  * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1610  *  call to __schedule(). This is an optimisation to avoid
1611  *  neighbouring rq clock updates.
1612  *
1613  * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1614  *  in effect and calls to update_rq_clock() are being ignored.
1615  *
1616  * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1617  *  made to update_rq_clock() since the last time rq::lock was pinned.
1618  *
1619  * If inside of __schedule(), clock_update_flags will have been
1620  * shifted left (a left shift is a cheap operation for the fast path
1621  * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1622  *
1623  *	if (rq-clock_update_flags >= RQCF_UPDATED)
1624  *
1625  * to check if %RQCF_UPDATED is set. It'll never be shifted more than
1626  * one position though, because the next rq_unpin_lock() will shift it
1627  * back.
1628  */
1629 #define RQCF_REQ_SKIP		0x01
1630 #define RQCF_ACT_SKIP		0x02
1631 #define RQCF_UPDATED		0x04
1632 
assert_clock_updated(struct rq * rq)1633 static inline void assert_clock_updated(struct rq *rq)
1634 {
1635 	/*
1636 	 * The only reason for not seeing a clock update since the
1637 	 * last rq_pin_lock() is if we're currently skipping updates.
1638 	 */
1639 	SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
1640 }
1641 
rq_clock(struct rq * rq)1642 static inline u64 rq_clock(struct rq *rq)
1643 {
1644 	lockdep_assert_rq_held(rq);
1645 	assert_clock_updated(rq);
1646 
1647 	return rq->clock;
1648 }
1649 
rq_clock_task(struct rq * rq)1650 static inline u64 rq_clock_task(struct rq *rq)
1651 {
1652 	lockdep_assert_rq_held(rq);
1653 	assert_clock_updated(rq);
1654 
1655 	return rq->clock_task;
1656 }
1657 
rq_clock_skip_update(struct rq * rq)1658 static inline void rq_clock_skip_update(struct rq *rq)
1659 {
1660 	lockdep_assert_rq_held(rq);
1661 	rq->clock_update_flags |= RQCF_REQ_SKIP;
1662 }
1663 
1664 /*
1665  * See rt task throttling, which is the only time a skip
1666  * request is canceled.
1667  */
rq_clock_cancel_skipupdate(struct rq * rq)1668 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1669 {
1670 	lockdep_assert_rq_held(rq);
1671 	rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1672 }
1673 
1674 /*
1675  * During cpu offlining and rq wide unthrottling, we can trigger
1676  * an update_rq_clock() for several cfs and rt runqueues (Typically
1677  * when using list_for_each_entry_*)
1678  * rq_clock_start_loop_update() can be called after updating the clock
1679  * once and before iterating over the list to prevent multiple update.
1680  * After the iterative traversal, we need to call rq_clock_stop_loop_update()
1681  * to clear RQCF_ACT_SKIP of rq->clock_update_flags.
1682  */
rq_clock_start_loop_update(struct rq * rq)1683 static inline void rq_clock_start_loop_update(struct rq *rq)
1684 {
1685 	lockdep_assert_rq_held(rq);
1686 	SCHED_WARN_ON(rq->clock_update_flags & RQCF_ACT_SKIP);
1687 	rq->clock_update_flags |= RQCF_ACT_SKIP;
1688 }
1689 
rq_clock_stop_loop_update(struct rq * rq)1690 static inline void rq_clock_stop_loop_update(struct rq *rq)
1691 {
1692 	lockdep_assert_rq_held(rq);
1693 	rq->clock_update_flags &= ~RQCF_ACT_SKIP;
1694 }
1695 
1696 struct rq_flags {
1697 	unsigned long flags;
1698 	struct pin_cookie cookie;
1699 #ifdef CONFIG_SCHED_DEBUG
1700 	/*
1701 	 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1702 	 * current pin context is stashed here in case it needs to be
1703 	 * restored in rq_repin_lock().
1704 	 */
1705 	unsigned int clock_update_flags;
1706 #endif
1707 };
1708 
1709 extern struct balance_callback balance_push_callback;
1710 
1711 /*
1712  * Lockdep annotation that avoids accidental unlocks; it's like a
1713  * sticky/continuous lockdep_assert_held().
1714  *
1715  * This avoids code that has access to 'struct rq *rq' (basically everything in
1716  * the scheduler) from accidentally unlocking the rq if they do not also have a
1717  * copy of the (on-stack) 'struct rq_flags rf'.
1718  *
1719  * Also see Documentation/locking/lockdep-design.rst.
1720  */
rq_pin_lock(struct rq * rq,struct rq_flags * rf)1721 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1722 {
1723 	rf->cookie = lockdep_pin_lock(__rq_lockp(rq));
1724 
1725 #ifdef CONFIG_SCHED_DEBUG
1726 	rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1727 	rf->clock_update_flags = 0;
1728 # ifdef CONFIG_SMP
1729 	SCHED_WARN_ON(rq->balance_callback && rq->balance_callback != &balance_push_callback);
1730 # endif
1731 #endif
1732 }
1733 
rq_unpin_lock(struct rq * rq,struct rq_flags * rf)1734 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1735 {
1736 #ifdef CONFIG_SCHED_DEBUG
1737 	if (rq->clock_update_flags > RQCF_ACT_SKIP)
1738 		rf->clock_update_flags = RQCF_UPDATED;
1739 #endif
1740 
1741 	lockdep_unpin_lock(__rq_lockp(rq), rf->cookie);
1742 }
1743 
rq_repin_lock(struct rq * rq,struct rq_flags * rf)1744 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1745 {
1746 	lockdep_repin_lock(__rq_lockp(rq), rf->cookie);
1747 
1748 #ifdef CONFIG_SCHED_DEBUG
1749 	/*
1750 	 * Restore the value we stashed in @rf for this pin context.
1751 	 */
1752 	rq->clock_update_flags |= rf->clock_update_flags;
1753 #endif
1754 }
1755 
1756 extern
1757 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1758 	__acquires(rq->lock);
1759 
1760 extern
1761 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1762 	__acquires(p->pi_lock)
1763 	__acquires(rq->lock);
1764 
__task_rq_unlock(struct rq * rq,struct rq_flags * rf)1765 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1766 	__releases(rq->lock)
1767 {
1768 	rq_unpin_lock(rq, rf);
1769 	raw_spin_rq_unlock(rq);
1770 }
1771 
1772 static inline void
task_rq_unlock(struct rq * rq,struct task_struct * p,struct rq_flags * rf)1773 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1774 	__releases(rq->lock)
1775 	__releases(p->pi_lock)
1776 {
1777 	rq_unpin_lock(rq, rf);
1778 	raw_spin_rq_unlock(rq);
1779 	raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1780 }
1781 
1782 DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct,
1783 		    _T->rq = task_rq_lock(_T->lock, &_T->rf),
1784 		    task_rq_unlock(_T->rq, _T->lock, &_T->rf),
1785 		    struct rq *rq; struct rq_flags rf)
1786 
rq_lock_irqsave(struct rq * rq,struct rq_flags * rf)1787 static inline void rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1788 	__acquires(rq->lock)
1789 {
1790 	raw_spin_rq_lock_irqsave(rq, rf->flags);
1791 	rq_pin_lock(rq, rf);
1792 }
1793 
rq_lock_irq(struct rq * rq,struct rq_flags * rf)1794 static inline void rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1795 	__acquires(rq->lock)
1796 {
1797 	raw_spin_rq_lock_irq(rq);
1798 	rq_pin_lock(rq, rf);
1799 }
1800 
rq_lock(struct rq * rq,struct rq_flags * rf)1801 static inline void rq_lock(struct rq *rq, struct rq_flags *rf)
1802 	__acquires(rq->lock)
1803 {
1804 	raw_spin_rq_lock(rq);
1805 	rq_pin_lock(rq, rf);
1806 }
1807 
rq_unlock_irqrestore(struct rq * rq,struct rq_flags * rf)1808 static inline void rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1809 	__releases(rq->lock)
1810 {
1811 	rq_unpin_lock(rq, rf);
1812 	raw_spin_rq_unlock_irqrestore(rq, rf->flags);
1813 }
1814 
rq_unlock_irq(struct rq * rq,struct rq_flags * rf)1815 static inline void rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1816 	__releases(rq->lock)
1817 {
1818 	rq_unpin_lock(rq, rf);
1819 	raw_spin_rq_unlock_irq(rq);
1820 }
1821 
rq_unlock(struct rq * rq,struct rq_flags * rf)1822 static inline void rq_unlock(struct rq *rq, struct rq_flags *rf)
1823 	__releases(rq->lock)
1824 {
1825 	rq_unpin_lock(rq, rf);
1826 	raw_spin_rq_unlock(rq);
1827 }
1828 
1829 DEFINE_LOCK_GUARD_1(rq_lock, struct rq,
1830 		    rq_lock(_T->lock, &_T->rf),
1831 		    rq_unlock(_T->lock, &_T->rf),
1832 		    struct rq_flags rf)
1833 
1834 DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq,
1835 		    rq_lock_irq(_T->lock, &_T->rf),
1836 		    rq_unlock_irq(_T->lock, &_T->rf),
1837 		    struct rq_flags rf)
1838 
1839 DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq,
1840 		    rq_lock_irqsave(_T->lock, &_T->rf),
1841 		    rq_unlock_irqrestore(_T->lock, &_T->rf),
1842 		    struct rq_flags rf)
1843 
this_rq_lock_irq(struct rq_flags * rf)1844 static inline struct rq *this_rq_lock_irq(struct rq_flags *rf)
1845 	__acquires(rq->lock)
1846 {
1847 	struct rq *rq;
1848 
1849 	local_irq_disable();
1850 	rq = this_rq();
1851 	rq_lock(rq, rf);
1852 
1853 	return rq;
1854 }
1855 
1856 #ifdef CONFIG_NUMA
1857 
1858 enum numa_topology_type {
1859 	NUMA_DIRECT,
1860 	NUMA_GLUELESS_MESH,
1861 	NUMA_BACKPLANE,
1862 };
1863 
1864 extern enum numa_topology_type sched_numa_topology_type;
1865 extern int sched_max_numa_distance;
1866 extern bool find_numa_distance(int distance);
1867 extern void sched_init_numa(int offline_node);
1868 extern void sched_update_numa(int cpu, bool online);
1869 extern void sched_domains_numa_masks_set(unsigned int cpu);
1870 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1871 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1872 
1873 #else /* !CONFIG_NUMA: */
1874 
sched_init_numa(int offline_node)1875 static inline void sched_init_numa(int offline_node) { }
sched_update_numa(int cpu,bool online)1876 static inline void sched_update_numa(int cpu, bool online) { }
sched_domains_numa_masks_set(unsigned int cpu)1877 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
sched_domains_numa_masks_clear(unsigned int cpu)1878 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1879 
sched_numa_find_closest(const struct cpumask * cpus,int cpu)1880 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1881 {
1882 	return nr_cpu_ids;
1883 }
1884 
1885 #endif /* !CONFIG_NUMA */
1886 
1887 #ifdef CONFIG_NUMA_BALANCING
1888 
1889 /* The regions in numa_faults array from task_struct */
1890 enum numa_faults_stats {
1891 	NUMA_MEM = 0,
1892 	NUMA_CPU,
1893 	NUMA_MEMBUF,
1894 	NUMA_CPUBUF
1895 };
1896 
1897 extern void sched_setnuma(struct task_struct *p, int node);
1898 extern int migrate_task_to(struct task_struct *p, int cpu);
1899 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1900 			int cpu, int scpu);
1901 extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1902 
1903 #else /* !CONFIG_NUMA_BALANCING: */
1904 
1905 static inline void
init_numa_balancing(unsigned long clone_flags,struct task_struct * p)1906 init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1907 {
1908 }
1909 
1910 #endif /* !CONFIG_NUMA_BALANCING */
1911 
1912 #ifdef CONFIG_SMP
1913 
1914 static inline void
queue_balance_callback(struct rq * rq,struct balance_callback * head,void (* func)(struct rq * rq))1915 queue_balance_callback(struct rq *rq,
1916 		       struct balance_callback *head,
1917 		       void (*func)(struct rq *rq))
1918 {
1919 	lockdep_assert_rq_held(rq);
1920 
1921 	/*
1922 	 * Don't (re)queue an already queued item; nor queue anything when
1923 	 * balance_push() is active, see the comment with
1924 	 * balance_push_callback.
1925 	 */
1926 	if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
1927 		return;
1928 
1929 	head->func = func;
1930 	head->next = rq->balance_callback;
1931 	rq->balance_callback = head;
1932 }
1933 
1934 #define rcu_dereference_check_sched_domain(p) \
1935 	rcu_dereference_check((p), lockdep_is_held(&sched_domains_mutex))
1936 
1937 /*
1938  * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1939  * See destroy_sched_domains: call_rcu for details.
1940  *
1941  * The domain tree of any CPU may only be accessed from within
1942  * preempt-disabled sections.
1943  */
1944 #define for_each_domain(cpu, __sd) \
1945 	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1946 			__sd; __sd = __sd->parent)
1947 
1948 /* A mask of all the SD flags that have the SDF_SHARED_CHILD metaflag */
1949 #define SD_FLAG(name, mflags) (name * !!((mflags) & SDF_SHARED_CHILD)) |
1950 static const unsigned int SD_SHARED_CHILD_MASK =
1951 #include <linux/sched/sd_flags.h>
1952 0;
1953 #undef SD_FLAG
1954 
1955 /**
1956  * highest_flag_domain - Return highest sched_domain containing flag.
1957  * @cpu:	The CPU whose highest level of sched domain is to
1958  *		be returned.
1959  * @flag:	The flag to check for the highest sched_domain
1960  *		for the given CPU.
1961  *
1962  * Returns the highest sched_domain of a CPU which contains @flag. If @flag has
1963  * the SDF_SHARED_CHILD metaflag, all the children domains also have @flag.
1964  */
highest_flag_domain(int cpu,int flag)1965 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1966 {
1967 	struct sched_domain *sd, *hsd = NULL;
1968 
1969 	for_each_domain(cpu, sd) {
1970 		if (sd->flags & flag) {
1971 			hsd = sd;
1972 			continue;
1973 		}
1974 
1975 		/*
1976 		 * Stop the search if @flag is known to be shared at lower
1977 		 * levels. It will not be found further up.
1978 		 */
1979 		if (flag & SD_SHARED_CHILD_MASK)
1980 			break;
1981 	}
1982 
1983 	return hsd;
1984 }
1985 
lowest_flag_domain(int cpu,int flag)1986 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1987 {
1988 	struct sched_domain *sd;
1989 
1990 	for_each_domain(cpu, sd) {
1991 		if (sd->flags & flag)
1992 			break;
1993 	}
1994 
1995 	return sd;
1996 }
1997 
1998 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
1999 DECLARE_PER_CPU(int, sd_llc_size);
2000 DECLARE_PER_CPU(int, sd_llc_id);
2001 DECLARE_PER_CPU(int, sd_share_id);
2002 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
2003 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
2004 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
2005 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
2006 
2007 extern struct static_key_false sched_asym_cpucapacity;
2008 extern struct static_key_false sched_cluster_active;
2009 
sched_asym_cpucap_active(void)2010 static __always_inline bool sched_asym_cpucap_active(void)
2011 {
2012 	return static_branch_unlikely(&sched_asym_cpucapacity);
2013 }
2014 
2015 struct sched_group_capacity {
2016 	atomic_t		ref;
2017 	/*
2018 	 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
2019 	 * for a single CPU.
2020 	 */
2021 	unsigned long		capacity;
2022 	unsigned long		min_capacity;		/* Min per-CPU capacity in group */
2023 	unsigned long		max_capacity;		/* Max per-CPU capacity in group */
2024 	unsigned long		next_update;
2025 	int			imbalance;		/* XXX unrelated to capacity but shared group state */
2026 
2027 #ifdef CONFIG_SCHED_DEBUG
2028 	int			id;
2029 #endif
2030 
2031 	unsigned long		cpumask[];		/* Balance mask */
2032 };
2033 
2034 struct sched_group {
2035 	struct sched_group	*next;			/* Must be a circular list */
2036 	atomic_t		ref;
2037 
2038 	unsigned int		group_weight;
2039 	unsigned int		cores;
2040 	struct sched_group_capacity *sgc;
2041 	int			asym_prefer_cpu;	/* CPU of highest priority in group */
2042 	int			flags;
2043 
2044 	/*
2045 	 * The CPUs this group covers.
2046 	 *
2047 	 * NOTE: this field is variable length. (Allocated dynamically
2048 	 * by attaching extra space to the end of the structure,
2049 	 * depending on how many CPUs the kernel has booted up with)
2050 	 */
2051 	unsigned long		cpumask[];
2052 };
2053 
sched_group_span(struct sched_group * sg)2054 static inline struct cpumask *sched_group_span(struct sched_group *sg)
2055 {
2056 	return to_cpumask(sg->cpumask);
2057 }
2058 
2059 /*
2060  * See build_balance_mask().
2061  */
group_balance_mask(struct sched_group * sg)2062 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
2063 {
2064 	return to_cpumask(sg->sgc->cpumask);
2065 }
2066 
2067 extern int group_balance_cpu(struct sched_group *sg);
2068 
2069 #ifdef CONFIG_SCHED_DEBUG
2070 extern void update_sched_domain_debugfs(void);
2071 extern void dirty_sched_domain_sysctl(int cpu);
2072 #else
update_sched_domain_debugfs(void)2073 static inline void update_sched_domain_debugfs(void) { }
dirty_sched_domain_sysctl(int cpu)2074 static inline void dirty_sched_domain_sysctl(int cpu) { }
2075 #endif
2076 
2077 extern int sched_update_scaling(void);
2078 
task_user_cpus(struct task_struct * p)2079 static inline const struct cpumask *task_user_cpus(struct task_struct *p)
2080 {
2081 	if (!p->user_cpus_ptr)
2082 		return cpu_possible_mask; /* &init_task.cpus_mask */
2083 	return p->user_cpus_ptr;
2084 }
2085 
2086 #endif /* CONFIG_SMP */
2087 
2088 #include "stats.h"
2089 
2090 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS)
2091 
2092 extern void __sched_core_account_forceidle(struct rq *rq);
2093 
sched_core_account_forceidle(struct rq * rq)2094 static inline void sched_core_account_forceidle(struct rq *rq)
2095 {
2096 	if (schedstat_enabled())
2097 		__sched_core_account_forceidle(rq);
2098 }
2099 
2100 extern void __sched_core_tick(struct rq *rq);
2101 
sched_core_tick(struct rq * rq)2102 static inline void sched_core_tick(struct rq *rq)
2103 {
2104 	if (sched_core_enabled(rq) && schedstat_enabled())
2105 		__sched_core_tick(rq);
2106 }
2107 
2108 #else /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS): */
2109 
sched_core_account_forceidle(struct rq * rq)2110 static inline void sched_core_account_forceidle(struct rq *rq) { }
2111 
sched_core_tick(struct rq * rq)2112 static inline void sched_core_tick(struct rq *rq) { }
2113 
2114 #endif /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS) */
2115 
2116 #ifdef CONFIG_CGROUP_SCHED
2117 
2118 /*
2119  * Return the group to which this tasks belongs.
2120  *
2121  * We cannot use task_css() and friends because the cgroup subsystem
2122  * changes that value before the cgroup_subsys::attach() method is called,
2123  * therefore we cannot pin it and might observe the wrong value.
2124  *
2125  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
2126  * core changes this before calling sched_move_task().
2127  *
2128  * Instead we use a 'copy' which is updated from sched_move_task() while
2129  * holding both task_struct::pi_lock and rq::lock.
2130  */
task_group(struct task_struct * p)2131 static inline struct task_group *task_group(struct task_struct *p)
2132 {
2133 	return p->sched_task_group;
2134 }
2135 
2136 /* 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)2137 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
2138 {
2139 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
2140 	struct task_group *tg = task_group(p);
2141 #endif
2142 
2143 #ifdef CONFIG_FAIR_GROUP_SCHED
2144 	set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
2145 	p->se.cfs_rq = tg->cfs_rq[cpu];
2146 	p->se.parent = tg->se[cpu];
2147 	p->se.depth = tg->se[cpu] ? tg->se[cpu]->depth + 1 : 0;
2148 #endif
2149 
2150 #ifdef CONFIG_RT_GROUP_SCHED
2151 	p->rt.rt_rq  = tg->rt_rq[cpu];
2152 	p->rt.parent = tg->rt_se[cpu];
2153 #endif
2154 }
2155 
2156 #else /* !CONFIG_CGROUP_SCHED: */
2157 
set_task_rq(struct task_struct * p,unsigned int cpu)2158 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
2159 
task_group(struct task_struct * p)2160 static inline struct task_group *task_group(struct task_struct *p)
2161 {
2162 	return NULL;
2163 }
2164 
2165 #endif /* !CONFIG_CGROUP_SCHED */
2166 
__set_task_cpu(struct task_struct * p,unsigned int cpu)2167 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
2168 {
2169 	set_task_rq(p, cpu);
2170 #ifdef CONFIG_SMP
2171 	/*
2172 	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
2173 	 * successfully executed on another CPU. We must ensure that updates of
2174 	 * per-task data have been completed by this moment.
2175 	 */
2176 	smp_wmb();
2177 	WRITE_ONCE(task_thread_info(p)->cpu, cpu);
2178 	p->wake_cpu = cpu;
2179 #endif
2180 }
2181 
2182 /*
2183  * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
2184  */
2185 #ifdef CONFIG_SCHED_DEBUG
2186 # define const_debug __read_mostly
2187 #else
2188 # define const_debug const
2189 #endif
2190 
2191 #define SCHED_FEAT(name, enabled)	\
2192 	__SCHED_FEAT_##name ,
2193 
2194 enum {
2195 #include "features.h"
2196 	__SCHED_FEAT_NR,
2197 };
2198 
2199 #undef SCHED_FEAT
2200 
2201 #ifdef CONFIG_SCHED_DEBUG
2202 
2203 /*
2204  * To support run-time toggling of sched features, all the translation units
2205  * (but core.c) reference the sysctl_sched_features defined in core.c.
2206  */
2207 extern const_debug unsigned int sysctl_sched_features;
2208 
2209 #ifdef CONFIG_JUMP_LABEL
2210 
2211 #define SCHED_FEAT(name, enabled)					\
2212 static __always_inline bool static_branch_##name(struct static_key *key) \
2213 {									\
2214 	return static_key_##enabled(key);				\
2215 }
2216 
2217 #include "features.h"
2218 #undef SCHED_FEAT
2219 
2220 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
2221 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
2222 
2223 #else /* !CONFIG_JUMP_LABEL: */
2224 
2225 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2226 
2227 #endif /* !CONFIG_JUMP_LABEL */
2228 
2229 #else /* !SCHED_DEBUG: */
2230 
2231 /*
2232  * Each translation unit has its own copy of sysctl_sched_features to allow
2233  * constants propagation at compile time and compiler optimization based on
2234  * features default.
2235  */
2236 #define SCHED_FEAT(name, enabled)	\
2237 	(1UL << __SCHED_FEAT_##name) * enabled |
2238 static const_debug __maybe_unused unsigned int sysctl_sched_features =
2239 #include "features.h"
2240 	0;
2241 #undef SCHED_FEAT
2242 
2243 #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2244 
2245 #endif /* !SCHED_DEBUG */
2246 
2247 extern struct static_key_false sched_numa_balancing;
2248 extern struct static_key_false sched_schedstats;
2249 
global_rt_period(void)2250 static inline u64 global_rt_period(void)
2251 {
2252 	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
2253 }
2254 
global_rt_runtime(void)2255 static inline u64 global_rt_runtime(void)
2256 {
2257 	if (sysctl_sched_rt_runtime < 0)
2258 		return RUNTIME_INF;
2259 
2260 	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
2261 }
2262 
task_current(struct rq * rq,struct task_struct * p)2263 static inline int task_current(struct rq *rq, struct task_struct *p)
2264 {
2265 	return rq->curr == p;
2266 }
2267 
task_on_cpu(struct rq * rq,struct task_struct * p)2268 static inline int task_on_cpu(struct rq *rq, struct task_struct *p)
2269 {
2270 #ifdef CONFIG_SMP
2271 	return p->on_cpu;
2272 #else
2273 	return task_current(rq, p);
2274 #endif
2275 }
2276 
task_on_rq_queued(struct task_struct * p)2277 static inline int task_on_rq_queued(struct task_struct *p)
2278 {
2279 	return p->on_rq == TASK_ON_RQ_QUEUED;
2280 }
2281 
task_on_rq_migrating(struct task_struct * p)2282 static inline int task_on_rq_migrating(struct task_struct *p)
2283 {
2284 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
2285 }
2286 
2287 /* Wake flags. The first three directly map to some SD flag value */
2288 #define WF_EXEC			0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
2289 #define WF_FORK			0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
2290 #define WF_TTWU			0x08 /* Wakeup;            maps to SD_BALANCE_WAKE */
2291 
2292 #define WF_SYNC			0x10 /* Waker goes to sleep after wakeup */
2293 #define WF_MIGRATED		0x20 /* Internal use, task got migrated */
2294 #define WF_CURRENT_CPU		0x40 /* Prefer to move the wakee to the current CPU. */
2295 #define WF_RQ_SELECTED		0x80 /* ->select_task_rq() was called */
2296 
2297 #ifdef CONFIG_SMP
2298 static_assert(WF_EXEC == SD_BALANCE_EXEC);
2299 static_assert(WF_FORK == SD_BALANCE_FORK);
2300 static_assert(WF_TTWU == SD_BALANCE_WAKE);
2301 #endif
2302 
2303 /*
2304  * To aid in avoiding the subversion of "niceness" due to uneven distribution
2305  * of tasks with abnormal "nice" values across CPUs the contribution that
2306  * each task makes to its run queue's load is weighted according to its
2307  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
2308  * scaled version of the new time slice allocation that they receive on time
2309  * slice expiry etc.
2310  */
2311 
2312 #define WEIGHT_IDLEPRIO		3
2313 #define WMULT_IDLEPRIO		1431655765
2314 
2315 extern const int		sched_prio_to_weight[40];
2316 extern const u32		sched_prio_to_wmult[40];
2317 
2318 /*
2319  * {de,en}queue flags:
2320  *
2321  * DEQUEUE_SLEEP  - task is no longer runnable
2322  * ENQUEUE_WAKEUP - task just became runnable
2323  *
2324  * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
2325  *                are in a known state which allows modification. Such pairs
2326  *                should preserve as much state as possible.
2327  *
2328  * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
2329  *        in the runqueue.
2330  *
2331  * NOCLOCK - skip the update_rq_clock() (avoids double updates)
2332  *
2333  * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE)
2334  *
2335  * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
2336  * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
2337  * ENQUEUE_MIGRATED  - the task was migrated during wakeup
2338  * ENQUEUE_RQ_SELECTED - ->select_task_rq() was called
2339  *
2340  */
2341 
2342 #define DEQUEUE_SLEEP		0x01 /* Matches ENQUEUE_WAKEUP */
2343 #define DEQUEUE_SAVE		0x02 /* Matches ENQUEUE_RESTORE */
2344 #define DEQUEUE_MOVE		0x04 /* Matches ENQUEUE_MOVE */
2345 #define DEQUEUE_NOCLOCK		0x08 /* Matches ENQUEUE_NOCLOCK */
2346 #define DEQUEUE_SPECIAL		0x10
2347 #define DEQUEUE_MIGRATING	0x100 /* Matches ENQUEUE_MIGRATING */
2348 #define DEQUEUE_DELAYED		0x200 /* Matches ENQUEUE_DELAYED */
2349 
2350 #define ENQUEUE_WAKEUP		0x01
2351 #define ENQUEUE_RESTORE		0x02
2352 #define ENQUEUE_MOVE		0x04
2353 #define ENQUEUE_NOCLOCK		0x08
2354 
2355 #define ENQUEUE_HEAD		0x10
2356 #define ENQUEUE_REPLENISH	0x20
2357 #ifdef CONFIG_SMP
2358 #define ENQUEUE_MIGRATED	0x40
2359 #else
2360 #define ENQUEUE_MIGRATED	0x00
2361 #endif
2362 #define ENQUEUE_INITIAL		0x80
2363 #define ENQUEUE_MIGRATING	0x100
2364 #define ENQUEUE_DELAYED		0x200
2365 #define ENQUEUE_RQ_SELECTED	0x400
2366 
2367 #define RETRY_TASK		((void *)-1UL)
2368 
2369 struct affinity_context {
2370 	const struct cpumask	*new_mask;
2371 	struct cpumask		*user_mask;
2372 	unsigned int		flags;
2373 };
2374 
2375 extern s64 update_curr_common(struct rq *rq);
2376 
2377 struct sched_class {
2378 
2379 #ifdef CONFIG_UCLAMP_TASK
2380 	int uclamp_enabled;
2381 #endif
2382 
2383 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
2384 	bool (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
2385 	void (*yield_task)   (struct rq *rq);
2386 	bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
2387 
2388 	void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags);
2389 
2390 	int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2391 	struct task_struct *(*pick_task)(struct rq *rq);
2392 	/*
2393 	 * Optional! When implemented pick_next_task() should be equivalent to:
2394 	 *
2395 	 *   next = pick_task();
2396 	 *   if (next) {
2397 	 *       put_prev_task(prev);
2398 	 *       set_next_task_first(next);
2399 	 *   }
2400 	 */
2401 	struct task_struct *(*pick_next_task)(struct rq *rq, struct task_struct *prev);
2402 
2403 	void (*put_prev_task)(struct rq *rq, struct task_struct *p, struct task_struct *next);
2404 	void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
2405 
2406 #ifdef CONFIG_SMP
2407 	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
2408 
2409 	void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
2410 
2411 	void (*task_woken)(struct rq *this_rq, struct task_struct *task);
2412 
2413 	void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx);
2414 
2415 	void (*rq_online)(struct rq *rq);
2416 	void (*rq_offline)(struct rq *rq);
2417 
2418 	struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
2419 #endif
2420 
2421 	void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
2422 	void (*task_fork)(struct task_struct *p);
2423 	void (*task_dead)(struct task_struct *p);
2424 
2425 	/*
2426 	 * The switched_from() call is allowed to drop rq->lock, therefore we
2427 	 * cannot assume the switched_from/switched_to pair is serialized by
2428 	 * rq->lock. They are however serialized by p->pi_lock.
2429 	 */
2430 	void (*switching_to) (struct rq *this_rq, struct task_struct *task);
2431 	void (*switched_from)(struct rq *this_rq, struct task_struct *task);
2432 	void (*switched_to)  (struct rq *this_rq, struct task_struct *task);
2433 	void (*reweight_task)(struct rq *this_rq, struct task_struct *task,
2434 			      const struct load_weight *lw);
2435 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
2436 			      int oldprio);
2437 
2438 	unsigned int (*get_rr_interval)(struct rq *rq,
2439 					struct task_struct *task);
2440 
2441 	void (*update_curr)(struct rq *rq);
2442 
2443 #ifdef CONFIG_FAIR_GROUP_SCHED
2444 	void (*task_change_group)(struct task_struct *p);
2445 #endif
2446 
2447 #ifdef CONFIG_SCHED_CORE
2448 	int (*task_is_throttled)(struct task_struct *p, int cpu);
2449 #endif
2450 };
2451 
put_prev_task(struct rq * rq,struct task_struct * prev)2452 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
2453 {
2454 	WARN_ON_ONCE(rq->curr != prev);
2455 	prev->sched_class->put_prev_task(rq, prev, NULL);
2456 }
2457 
set_next_task(struct rq * rq,struct task_struct * next)2458 static inline void set_next_task(struct rq *rq, struct task_struct *next)
2459 {
2460 	next->sched_class->set_next_task(rq, next, false);
2461 }
2462 
2463 static inline void
__put_prev_set_next_dl_server(struct rq * rq,struct task_struct * prev,struct task_struct * next)2464 __put_prev_set_next_dl_server(struct rq *rq,
2465 			      struct task_struct *prev,
2466 			      struct task_struct *next)
2467 {
2468 	prev->dl_server = NULL;
2469 	next->dl_server = rq->dl_server;
2470 	rq->dl_server = NULL;
2471 }
2472 
put_prev_set_next_task(struct rq * rq,struct task_struct * prev,struct task_struct * next)2473 static inline void put_prev_set_next_task(struct rq *rq,
2474 					  struct task_struct *prev,
2475 					  struct task_struct *next)
2476 {
2477 	WARN_ON_ONCE(rq->curr != prev);
2478 
2479 	__put_prev_set_next_dl_server(rq, prev, next);
2480 
2481 	if (next == prev)
2482 		return;
2483 
2484 	prev->sched_class->put_prev_task(rq, prev, next);
2485 	next->sched_class->set_next_task(rq, next, true);
2486 }
2487 
2488 /*
2489  * Helper to define a sched_class instance; each one is placed in a separate
2490  * section which is ordered by the linker script:
2491  *
2492  *   include/asm-generic/vmlinux.lds.h
2493  *
2494  * *CAREFUL* they are laid out in *REVERSE* order!!!
2495  *
2496  * Also enforce alignment on the instance, not the type, to guarantee layout.
2497  */
2498 #define DEFINE_SCHED_CLASS(name) \
2499 const struct sched_class name##_sched_class \
2500 	__aligned(__alignof__(struct sched_class)) \
2501 	__section("__" #name "_sched_class")
2502 
2503 /* Defined in include/asm-generic/vmlinux.lds.h */
2504 extern struct sched_class __sched_class_highest[];
2505 extern struct sched_class __sched_class_lowest[];
2506 
2507 extern const struct sched_class stop_sched_class;
2508 extern const struct sched_class dl_sched_class;
2509 extern const struct sched_class rt_sched_class;
2510 extern const struct sched_class fair_sched_class;
2511 extern const struct sched_class idle_sched_class;
2512 
2513 #ifdef CONFIG_SCHED_CLASS_EXT
2514 extern const struct sched_class ext_sched_class;
2515 
2516 DECLARE_STATIC_KEY_FALSE(__scx_ops_enabled);	/* SCX BPF scheduler loaded */
2517 DECLARE_STATIC_KEY_FALSE(__scx_switched_all);	/* all fair class tasks on SCX */
2518 
2519 #define scx_enabled()		static_branch_unlikely(&__scx_ops_enabled)
2520 #define scx_switched_all()	static_branch_unlikely(&__scx_switched_all)
2521 #else /* !CONFIG_SCHED_CLASS_EXT */
2522 #define scx_enabled()		false
2523 #define scx_switched_all()	false
2524 #endif /* !CONFIG_SCHED_CLASS_EXT */
2525 
2526 /*
2527  * Iterate only active classes. SCX can take over all fair tasks or be
2528  * completely disabled. If the former, skip fair. If the latter, skip SCX.
2529  */
next_active_class(const struct sched_class * class)2530 static inline const struct sched_class *next_active_class(const struct sched_class *class)
2531 {
2532 	class++;
2533 #ifdef CONFIG_SCHED_CLASS_EXT
2534 	if (scx_switched_all() && class == &fair_sched_class)
2535 		class++;
2536 	if (!scx_enabled() && class == &ext_sched_class)
2537 		class++;
2538 #endif
2539 	return class;
2540 }
2541 
2542 #define for_class_range(class, _from, _to) \
2543 	for (class = (_from); class < (_to); class++)
2544 
2545 #define for_each_class(class) \
2546 	for_class_range(class, __sched_class_highest, __sched_class_lowest)
2547 
2548 #define for_active_class_range(class, _from, _to)				\
2549 	for (class = (_from); class != (_to); class = next_active_class(class))
2550 
2551 #define for_each_active_class(class)						\
2552 	for_active_class_range(class, __sched_class_highest, __sched_class_lowest)
2553 
2554 #define sched_class_above(_a, _b)	((_a) < (_b))
2555 
sched_stop_runnable(struct rq * rq)2556 static inline bool sched_stop_runnable(struct rq *rq)
2557 {
2558 	return rq->stop && task_on_rq_queued(rq->stop);
2559 }
2560 
sched_dl_runnable(struct rq * rq)2561 static inline bool sched_dl_runnable(struct rq *rq)
2562 {
2563 	return rq->dl.dl_nr_running > 0;
2564 }
2565 
sched_rt_runnable(struct rq * rq)2566 static inline bool sched_rt_runnable(struct rq *rq)
2567 {
2568 	return rq->rt.rt_queued > 0;
2569 }
2570 
sched_fair_runnable(struct rq * rq)2571 static inline bool sched_fair_runnable(struct rq *rq)
2572 {
2573 	return rq->cfs.nr_running > 0;
2574 }
2575 
2576 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2577 extern struct task_struct *pick_task_idle(struct rq *rq);
2578 
2579 #define SCA_CHECK		0x01
2580 #define SCA_MIGRATE_DISABLE	0x02
2581 #define SCA_MIGRATE_ENABLE	0x04
2582 #define SCA_USER		0x08
2583 
2584 #ifdef CONFIG_SMP
2585 
2586 extern void update_group_capacity(struct sched_domain *sd, int cpu);
2587 
2588 extern void sched_balance_trigger(struct rq *rq);
2589 
2590 extern int __set_cpus_allowed_ptr(struct task_struct *p, struct affinity_context *ctx);
2591 extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx);
2592 
task_allowed_on_cpu(struct task_struct * p,int cpu)2593 static inline bool task_allowed_on_cpu(struct task_struct *p, int cpu)
2594 {
2595 	/* When not in the task's cpumask, no point in looking further. */
2596 	if (!cpumask_test_cpu(cpu, p->cpus_ptr))
2597 		return false;
2598 
2599 	/* Can @cpu run a user thread? */
2600 	if (!(p->flags & PF_KTHREAD) && !task_cpu_possible(cpu, p))
2601 		return false;
2602 
2603 	return true;
2604 }
2605 
alloc_user_cpus_ptr(int node)2606 static inline cpumask_t *alloc_user_cpus_ptr(int node)
2607 {
2608 	/*
2609 	 * See do_set_cpus_allowed() above for the rcu_head usage.
2610 	 */
2611 	int size = max_t(int, cpumask_size(), sizeof(struct rcu_head));
2612 
2613 	return kmalloc_node(size, GFP_KERNEL, node);
2614 }
2615 
get_push_task(struct rq * rq)2616 static inline struct task_struct *get_push_task(struct rq *rq)
2617 {
2618 	struct task_struct *p = rq->curr;
2619 
2620 	lockdep_assert_rq_held(rq);
2621 
2622 	if (rq->push_busy)
2623 		return NULL;
2624 
2625 	if (p->nr_cpus_allowed == 1)
2626 		return NULL;
2627 
2628 	if (p->migration_disabled)
2629 		return NULL;
2630 
2631 	rq->push_busy = true;
2632 	return get_task_struct(p);
2633 }
2634 
2635 extern int push_cpu_stop(void *arg);
2636 
2637 #else /* !CONFIG_SMP: */
2638 
task_allowed_on_cpu(struct task_struct * p,int cpu)2639 static inline bool task_allowed_on_cpu(struct task_struct *p, int cpu)
2640 {
2641 	return true;
2642 }
2643 
__set_cpus_allowed_ptr(struct task_struct * p,struct affinity_context * ctx)2644 static inline int __set_cpus_allowed_ptr(struct task_struct *p,
2645 					 struct affinity_context *ctx)
2646 {
2647 	return set_cpus_allowed_ptr(p, ctx->new_mask);
2648 }
2649 
alloc_user_cpus_ptr(int node)2650 static inline cpumask_t *alloc_user_cpus_ptr(int node)
2651 {
2652 	return NULL;
2653 }
2654 
2655 #endif /* !CONFIG_SMP */
2656 
2657 #ifdef CONFIG_CPU_IDLE
2658 
idle_set_state(struct rq * rq,struct cpuidle_state * idle_state)2659 static inline void idle_set_state(struct rq *rq,
2660 				  struct cpuidle_state *idle_state)
2661 {
2662 	rq->idle_state = idle_state;
2663 }
2664 
idle_get_state(struct rq * rq)2665 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2666 {
2667 	SCHED_WARN_ON(!rcu_read_lock_held());
2668 
2669 	return rq->idle_state;
2670 }
2671 
2672 #else /* !CONFIG_CPU_IDLE: */
2673 
idle_set_state(struct rq * rq,struct cpuidle_state * idle_state)2674 static inline void idle_set_state(struct rq *rq,
2675 				  struct cpuidle_state *idle_state)
2676 {
2677 }
2678 
idle_get_state(struct rq * rq)2679 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2680 {
2681 	return NULL;
2682 }
2683 
2684 #endif /* !CONFIG_CPU_IDLE */
2685 
2686 extern void schedule_idle(void);
2687 asmlinkage void schedule_user(void);
2688 
2689 extern void sysrq_sched_debug_show(void);
2690 extern void sched_init_granularity(void);
2691 extern void update_max_interval(void);
2692 
2693 extern void init_sched_dl_class(void);
2694 extern void init_sched_rt_class(void);
2695 extern void init_sched_fair_class(void);
2696 
2697 extern void resched_curr(struct rq *rq);
2698 extern void resched_cpu(int cpu);
2699 
2700 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
2701 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq);
2702 
2703 extern void init_dl_entity(struct sched_dl_entity *dl_se);
2704 
2705 #define BW_SHIFT		20
2706 #define BW_UNIT			(1 << BW_SHIFT)
2707 #define RATIO_SHIFT		8
2708 #define MAX_BW_BITS		(64 - BW_SHIFT)
2709 #define MAX_BW			((1ULL << MAX_BW_BITS) - 1)
2710 
2711 extern unsigned long to_ratio(u64 period, u64 runtime);
2712 
2713 extern void init_entity_runnable_average(struct sched_entity *se);
2714 extern void post_init_entity_util_avg(struct task_struct *p);
2715 
2716 #ifdef CONFIG_NO_HZ_FULL
2717 extern bool sched_can_stop_tick(struct rq *rq);
2718 extern int __init sched_tick_offload_init(void);
2719 
2720 /*
2721  * Tick may be needed by tasks in the runqueue depending on their policy and
2722  * requirements. If tick is needed, lets send the target an IPI to kick it out of
2723  * nohz mode if necessary.
2724  */
sched_update_tick_dependency(struct rq * rq)2725 static inline void sched_update_tick_dependency(struct rq *rq)
2726 {
2727 	int cpu = cpu_of(rq);
2728 
2729 	if (!tick_nohz_full_cpu(cpu))
2730 		return;
2731 
2732 	if (sched_can_stop_tick(rq))
2733 		tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
2734 	else
2735 		tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
2736 }
2737 #else /* !CONFIG_NO_HZ_FULL: */
sched_tick_offload_init(void)2738 static inline int sched_tick_offload_init(void) { return 0; }
sched_update_tick_dependency(struct rq * rq)2739 static inline void sched_update_tick_dependency(struct rq *rq) { }
2740 #endif /* !CONFIG_NO_HZ_FULL */
2741 
add_nr_running(struct rq * rq,unsigned count)2742 static inline void add_nr_running(struct rq *rq, unsigned count)
2743 {
2744 	unsigned prev_nr = rq->nr_running;
2745 
2746 	rq->nr_running = prev_nr + count;
2747 	if (trace_sched_update_nr_running_tp_enabled()) {
2748 		call_trace_sched_update_nr_running(rq, count);
2749 	}
2750 
2751 #ifdef CONFIG_SMP
2752 	if (prev_nr < 2 && rq->nr_running >= 2)
2753 		set_rd_overloaded(rq->rd, 1);
2754 #endif
2755 
2756 	sched_update_tick_dependency(rq);
2757 }
2758 
sub_nr_running(struct rq * rq,unsigned count)2759 static inline void sub_nr_running(struct rq *rq, unsigned count)
2760 {
2761 	rq->nr_running -= count;
2762 	if (trace_sched_update_nr_running_tp_enabled()) {
2763 		call_trace_sched_update_nr_running(rq, -count);
2764 	}
2765 
2766 	/* Check if we still need preemption */
2767 	sched_update_tick_dependency(rq);
2768 }
2769 
__block_task(struct rq * rq,struct task_struct * p)2770 static inline void __block_task(struct rq *rq, struct task_struct *p)
2771 {
2772 	if (p->sched_contributes_to_load)
2773 		rq->nr_uninterruptible++;
2774 
2775 	if (p->in_iowait) {
2776 		atomic_inc(&rq->nr_iowait);
2777 		delayacct_blkio_start();
2778 	}
2779 
2780 	ASSERT_EXCLUSIVE_WRITER(p->on_rq);
2781 
2782 	/*
2783 	 * The moment this write goes through, ttwu() can swoop in and migrate
2784 	 * this task, rendering our rq->__lock ineffective.
2785 	 *
2786 	 * __schedule()				try_to_wake_up()
2787 	 *   LOCK rq->__lock			  LOCK p->pi_lock
2788 	 *   pick_next_task()
2789 	 *     pick_next_task_fair()
2790 	 *       pick_next_entity()
2791 	 *         dequeue_entities()
2792 	 *           __block_task()
2793 	 *             RELEASE p->on_rq = 0	  if (p->on_rq && ...)
2794 	 *					    break;
2795 	 *
2796 	 *					  ACQUIRE (after ctrl-dep)
2797 	 *
2798 	 *					  cpu = select_task_rq();
2799 	 *					  set_task_cpu(p, cpu);
2800 	 *					  ttwu_queue()
2801 	 *					    ttwu_do_activate()
2802 	 *					      LOCK rq->__lock
2803 	 *					      activate_task()
2804 	 *					        STORE p->on_rq = 1
2805 	 *   UNLOCK rq->__lock
2806 	 *
2807 	 * Callers must ensure to not reference @p after this -- we no longer
2808 	 * own it.
2809 	 */
2810 	smp_store_release(&p->on_rq, 0);
2811 }
2812 
2813 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
2814 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
2815 
2816 extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags);
2817 
2818 #ifdef CONFIG_PREEMPT_RT
2819 # define SCHED_NR_MIGRATE_BREAK 8
2820 #else
2821 # define SCHED_NR_MIGRATE_BREAK 32
2822 #endif
2823 
2824 extern const_debug unsigned int sysctl_sched_nr_migrate;
2825 extern const_debug unsigned int sysctl_sched_migration_cost;
2826 
2827 extern unsigned int sysctl_sched_base_slice;
2828 
2829 #ifdef CONFIG_SCHED_DEBUG
2830 extern int sysctl_resched_latency_warn_ms;
2831 extern int sysctl_resched_latency_warn_once;
2832 
2833 extern unsigned int sysctl_sched_tunable_scaling;
2834 
2835 extern unsigned int sysctl_numa_balancing_scan_delay;
2836 extern unsigned int sysctl_numa_balancing_scan_period_min;
2837 extern unsigned int sysctl_numa_balancing_scan_period_max;
2838 extern unsigned int sysctl_numa_balancing_scan_size;
2839 extern unsigned int sysctl_numa_balancing_hot_threshold;
2840 #endif
2841 
2842 #ifdef CONFIG_SCHED_HRTICK
2843 
2844 /*
2845  * Use hrtick when:
2846  *  - enabled by features
2847  *  - hrtimer is actually high res
2848  */
hrtick_enabled(struct rq * rq)2849 static inline int hrtick_enabled(struct rq *rq)
2850 {
2851 	if (!cpu_active(cpu_of(rq)))
2852 		return 0;
2853 	return hrtimer_is_hres_active(&rq->hrtick_timer);
2854 }
2855 
hrtick_enabled_fair(struct rq * rq)2856 static inline int hrtick_enabled_fair(struct rq *rq)
2857 {
2858 	if (!sched_feat(HRTICK))
2859 		return 0;
2860 	return hrtick_enabled(rq);
2861 }
2862 
hrtick_enabled_dl(struct rq * rq)2863 static inline int hrtick_enabled_dl(struct rq *rq)
2864 {
2865 	if (!sched_feat(HRTICK_DL))
2866 		return 0;
2867 	return hrtick_enabled(rq);
2868 }
2869 
2870 extern void hrtick_start(struct rq *rq, u64 delay);
2871 
2872 #else /* !CONFIG_SCHED_HRTICK: */
2873 
hrtick_enabled_fair(struct rq * rq)2874 static inline int hrtick_enabled_fair(struct rq *rq)
2875 {
2876 	return 0;
2877 }
2878 
hrtick_enabled_dl(struct rq * rq)2879 static inline int hrtick_enabled_dl(struct rq *rq)
2880 {
2881 	return 0;
2882 }
2883 
hrtick_enabled(struct rq * rq)2884 static inline int hrtick_enabled(struct rq *rq)
2885 {
2886 	return 0;
2887 }
2888 
2889 #endif /* !CONFIG_SCHED_HRTICK */
2890 
2891 #ifndef arch_scale_freq_tick
arch_scale_freq_tick(void)2892 static __always_inline void arch_scale_freq_tick(void) { }
2893 #endif
2894 
2895 #ifndef arch_scale_freq_capacity
2896 /**
2897  * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
2898  * @cpu: the CPU in question.
2899  *
2900  * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
2901  *
2902  *     f_curr
2903  *     ------ * SCHED_CAPACITY_SCALE
2904  *     f_max
2905  */
2906 static __always_inline
arch_scale_freq_capacity(int cpu)2907 unsigned long arch_scale_freq_capacity(int cpu)
2908 {
2909 	return SCHED_CAPACITY_SCALE;
2910 }
2911 #endif
2912 
2913 #ifdef CONFIG_SCHED_DEBUG
2914 /*
2915  * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to
2916  * acquire rq lock instead of rq_lock(). So at the end of these two functions
2917  * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of
2918  * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning.
2919  */
double_rq_clock_clear_update(struct rq * rq1,struct rq * rq2)2920 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2)
2921 {
2922 	rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
2923 	/* rq1 == rq2 for !CONFIG_SMP, so just clear RQCF_UPDATED once. */
2924 #ifdef CONFIG_SMP
2925 	rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
2926 #endif
2927 }
2928 #else
double_rq_clock_clear_update(struct rq * rq1,struct rq * rq2)2929 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2) { }
2930 #endif
2931 
2932 #define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...)				\
2933 __DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__)			\
2934 static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2)	\
2935 { class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t;			\
2936   _lock; return _t; }
2937 
2938 #ifdef CONFIG_SMP
2939 
rq_order_less(struct rq * rq1,struct rq * rq2)2940 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2)
2941 {
2942 #ifdef CONFIG_SCHED_CORE
2943 	/*
2944 	 * In order to not have {0,2},{1,3} turn into into an AB-BA,
2945 	 * order by core-id first and cpu-id second.
2946 	 *
2947 	 * Notably:
2948 	 *
2949 	 *	double_rq_lock(0,3); will take core-0, core-1 lock
2950 	 *	double_rq_lock(1,2); will take core-1, core-0 lock
2951 	 *
2952 	 * when only cpu-id is considered.
2953 	 */
2954 	if (rq1->core->cpu < rq2->core->cpu)
2955 		return true;
2956 	if (rq1->core->cpu > rq2->core->cpu)
2957 		return false;
2958 
2959 	/*
2960 	 * __sched_core_flip() relies on SMT having cpu-id lock order.
2961 	 */
2962 #endif
2963 	return rq1->cpu < rq2->cpu;
2964 }
2965 
2966 extern void double_rq_lock(struct rq *rq1, struct rq *rq2);
2967 
2968 #ifdef CONFIG_PREEMPTION
2969 
2970 /*
2971  * fair double_lock_balance: Safely acquires both rq->locks in a fair
2972  * way at the expense of forcing extra atomic operations in all
2973  * invocations.  This assures that the double_lock is acquired using the
2974  * same underlying policy as the spinlock_t on this architecture, which
2975  * reduces latency compared to the unfair variant below.  However, it
2976  * also adds more overhead and therefore may reduce throughput.
2977  */
_double_lock_balance(struct rq * this_rq,struct rq * busiest)2978 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2979 	__releases(this_rq->lock)
2980 	__acquires(busiest->lock)
2981 	__acquires(this_rq->lock)
2982 {
2983 	raw_spin_rq_unlock(this_rq);
2984 	double_rq_lock(this_rq, busiest);
2985 
2986 	return 1;
2987 }
2988 
2989 #else /* !CONFIG_PREEMPTION: */
2990 /*
2991  * Unfair double_lock_balance: Optimizes throughput at the expense of
2992  * latency by eliminating extra atomic operations when the locks are
2993  * already in proper order on entry.  This favors lower CPU-ids and will
2994  * grant the double lock to lower CPUs over higher ids under contention,
2995  * regardless of entry order into the function.
2996  */
_double_lock_balance(struct rq * this_rq,struct rq * busiest)2997 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2998 	__releases(this_rq->lock)
2999 	__acquires(busiest->lock)
3000 	__acquires(this_rq->lock)
3001 {
3002 	if (__rq_lockp(this_rq) == __rq_lockp(busiest) ||
3003 	    likely(raw_spin_rq_trylock(busiest))) {
3004 		double_rq_clock_clear_update(this_rq, busiest);
3005 		return 0;
3006 	}
3007 
3008 	if (rq_order_less(this_rq, busiest)) {
3009 		raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING);
3010 		double_rq_clock_clear_update(this_rq, busiest);
3011 		return 0;
3012 	}
3013 
3014 	raw_spin_rq_unlock(this_rq);
3015 	double_rq_lock(this_rq, busiest);
3016 
3017 	return 1;
3018 }
3019 
3020 #endif /* !CONFIG_PREEMPTION */
3021 
3022 /*
3023  * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
3024  */
double_lock_balance(struct rq * this_rq,struct rq * busiest)3025 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
3026 {
3027 	lockdep_assert_irqs_disabled();
3028 
3029 	return _double_lock_balance(this_rq, busiest);
3030 }
3031 
double_unlock_balance(struct rq * this_rq,struct rq * busiest)3032 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
3033 	__releases(busiest->lock)
3034 {
3035 	if (__rq_lockp(this_rq) != __rq_lockp(busiest))
3036 		raw_spin_rq_unlock(busiest);
3037 	lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_);
3038 }
3039 
double_lock(spinlock_t * l1,spinlock_t * l2)3040 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
3041 {
3042 	if (l1 > l2)
3043 		swap(l1, l2);
3044 
3045 	spin_lock(l1);
3046 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3047 }
3048 
double_lock_irq(spinlock_t * l1,spinlock_t * l2)3049 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
3050 {
3051 	if (l1 > l2)
3052 		swap(l1, l2);
3053 
3054 	spin_lock_irq(l1);
3055 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3056 }
3057 
double_raw_lock(raw_spinlock_t * l1,raw_spinlock_t * l2)3058 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
3059 {
3060 	if (l1 > l2)
3061 		swap(l1, l2);
3062 
3063 	raw_spin_lock(l1);
3064 	raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3065 }
3066 
double_raw_unlock(raw_spinlock_t * l1,raw_spinlock_t * l2)3067 static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2)
3068 {
3069 	raw_spin_unlock(l1);
3070 	raw_spin_unlock(l2);
3071 }
3072 
3073 DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t,
3074 		    double_raw_lock(_T->lock, _T->lock2),
3075 		    double_raw_unlock(_T->lock, _T->lock2))
3076 
3077 /*
3078  * double_rq_unlock - safely unlock two runqueues
3079  *
3080  * Note this does not restore interrupts like task_rq_unlock,
3081  * you need to do so manually after calling.
3082  */
double_rq_unlock(struct rq * rq1,struct rq * rq2)3083 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
3084 	__releases(rq1->lock)
3085 	__releases(rq2->lock)
3086 {
3087 	if (__rq_lockp(rq1) != __rq_lockp(rq2))
3088 		raw_spin_rq_unlock(rq2);
3089 	else
3090 		__release(rq2->lock);
3091 	raw_spin_rq_unlock(rq1);
3092 }
3093 
3094 extern void set_rq_online (struct rq *rq);
3095 extern void set_rq_offline(struct rq *rq);
3096 
3097 extern bool sched_smp_initialized;
3098 
3099 #else /* !CONFIG_SMP: */
3100 
3101 /*
3102  * double_rq_lock - safely lock two runqueues
3103  *
3104  * Note this does not disable interrupts like task_rq_lock,
3105  * you need to do so manually before calling.
3106  */
double_rq_lock(struct rq * rq1,struct rq * rq2)3107 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
3108 	__acquires(rq1->lock)
3109 	__acquires(rq2->lock)
3110 {
3111 	WARN_ON_ONCE(!irqs_disabled());
3112 	WARN_ON_ONCE(rq1 != rq2);
3113 	raw_spin_rq_lock(rq1);
3114 	__acquire(rq2->lock);	/* Fake it out ;) */
3115 	double_rq_clock_clear_update(rq1, rq2);
3116 }
3117 
3118 /*
3119  * double_rq_unlock - safely unlock two runqueues
3120  *
3121  * Note this does not restore interrupts like task_rq_unlock,
3122  * you need to do so manually after calling.
3123  */
double_rq_unlock(struct rq * rq1,struct rq * rq2)3124 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
3125 	__releases(rq1->lock)
3126 	__releases(rq2->lock)
3127 {
3128 	WARN_ON_ONCE(rq1 != rq2);
3129 	raw_spin_rq_unlock(rq1);
3130 	__release(rq2->lock);
3131 }
3132 
3133 #endif /* !CONFIG_SMP */
3134 
3135 DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq,
3136 		    double_rq_lock(_T->lock, _T->lock2),
3137 		    double_rq_unlock(_T->lock, _T->lock2))
3138 
3139 extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq);
3140 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
3141 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
3142 
3143 #ifdef	CONFIG_SCHED_DEBUG
3144 extern bool sched_debug_verbose;
3145 
3146 extern void print_cfs_stats(struct seq_file *m, int cpu);
3147 extern void print_rt_stats(struct seq_file *m, int cpu);
3148 extern void print_dl_stats(struct seq_file *m, int cpu);
3149 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
3150 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
3151 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
3152 
3153 extern void resched_latency_warn(int cpu, u64 latency);
3154 # ifdef CONFIG_NUMA_BALANCING
3155 extern void show_numa_stats(struct task_struct *p, struct seq_file *m);
3156 extern void
3157 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
3158 		 unsigned long tpf, unsigned long gsf, unsigned long gpf);
3159 # endif /* CONFIG_NUMA_BALANCING */
3160 #else /* !CONFIG_SCHED_DEBUG: */
resched_latency_warn(int cpu,u64 latency)3161 static inline void resched_latency_warn(int cpu, u64 latency) { }
3162 #endif /* !CONFIG_SCHED_DEBUG */
3163 
3164 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
3165 extern void init_rt_rq(struct rt_rq *rt_rq);
3166 extern void init_dl_rq(struct dl_rq *dl_rq);
3167 
3168 extern void cfs_bandwidth_usage_inc(void);
3169 extern void cfs_bandwidth_usage_dec(void);
3170 
3171 #ifdef CONFIG_NO_HZ_COMMON
3172 
3173 #define NOHZ_BALANCE_KICK_BIT	0
3174 #define NOHZ_STATS_KICK_BIT	1
3175 #define NOHZ_NEWILB_KICK_BIT	2
3176 #define NOHZ_NEXT_KICK_BIT	3
3177 
3178 /* Run sched_balance_domains() */
3179 #define NOHZ_BALANCE_KICK	BIT(NOHZ_BALANCE_KICK_BIT)
3180 /* Update blocked load */
3181 #define NOHZ_STATS_KICK		BIT(NOHZ_STATS_KICK_BIT)
3182 /* Update blocked load when entering idle */
3183 #define NOHZ_NEWILB_KICK	BIT(NOHZ_NEWILB_KICK_BIT)
3184 /* Update nohz.next_balance */
3185 #define NOHZ_NEXT_KICK		BIT(NOHZ_NEXT_KICK_BIT)
3186 
3187 #define NOHZ_KICK_MASK		(NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK)
3188 
3189 #define nohz_flags(cpu)		(&cpu_rq(cpu)->nohz_flags)
3190 
3191 extern void nohz_balance_exit_idle(struct rq *rq);
3192 #else /* !CONFIG_NO_HZ_COMMON: */
nohz_balance_exit_idle(struct rq * rq)3193 static inline void nohz_balance_exit_idle(struct rq *rq) { }
3194 #endif /* !CONFIG_NO_HZ_COMMON */
3195 
3196 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
3197 extern void nohz_run_idle_balance(int cpu);
3198 #else
nohz_run_idle_balance(int cpu)3199 static inline void nohz_run_idle_balance(int cpu) { }
3200 #endif
3201 
3202 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
3203 
3204 struct irqtime {
3205 	u64			total;
3206 	u64			tick_delta;
3207 	u64			irq_start_time;
3208 	struct u64_stats_sync	sync;
3209 };
3210 
3211 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
3212 
3213 /*
3214  * Returns the irqtime minus the softirq time computed by ksoftirqd.
3215  * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime
3216  * and never move forward.
3217  */
irq_time_read(int cpu)3218 static inline u64 irq_time_read(int cpu)
3219 {
3220 	struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
3221 	unsigned int seq;
3222 	u64 total;
3223 
3224 	do {
3225 		seq = __u64_stats_fetch_begin(&irqtime->sync);
3226 		total = irqtime->total;
3227 	} while (__u64_stats_fetch_retry(&irqtime->sync, seq));
3228 
3229 	return total;
3230 }
3231 
3232 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
3233 
3234 #ifdef CONFIG_CPU_FREQ
3235 
3236 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
3237 
3238 /**
3239  * cpufreq_update_util - Take a note about CPU utilization changes.
3240  * @rq: Runqueue to carry out the update for.
3241  * @flags: Update reason flags.
3242  *
3243  * This function is called by the scheduler on the CPU whose utilization is
3244  * being updated.
3245  *
3246  * It can only be called from RCU-sched read-side critical sections.
3247  *
3248  * The way cpufreq is currently arranged requires it to evaluate the CPU
3249  * performance state (frequency/voltage) on a regular basis to prevent it from
3250  * being stuck in a completely inadequate performance level for too long.
3251  * That is not guaranteed to happen if the updates are only triggered from CFS
3252  * and DL, though, because they may not be coming in if only RT tasks are
3253  * active all the time (or there are RT tasks only).
3254  *
3255  * As a workaround for that issue, this function is called periodically by the
3256  * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
3257  * but that really is a band-aid.  Going forward it should be replaced with
3258  * solutions targeted more specifically at RT tasks.
3259  */
cpufreq_update_util(struct rq * rq,unsigned int flags)3260 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
3261 {
3262 	struct update_util_data *data;
3263 
3264 	data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
3265 						  cpu_of(rq)));
3266 	if (data)
3267 		data->func(data, rq_clock(rq), flags);
3268 }
3269 #else /* !CONFIG_CPU_FREQ: */
cpufreq_update_util(struct rq * rq,unsigned int flags)3270 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) { }
3271 #endif /* !CONFIG_CPU_FREQ */
3272 
3273 #ifdef arch_scale_freq_capacity
3274 # ifndef arch_scale_freq_invariant
3275 #  define arch_scale_freq_invariant()	true
3276 # endif
3277 #else
3278 # define arch_scale_freq_invariant()	false
3279 #endif
3280 
3281 #ifdef CONFIG_SMP
3282 
3283 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
3284 				 unsigned long *min,
3285 				 unsigned long *max);
3286 
3287 unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual,
3288 				 unsigned long min,
3289 				 unsigned long max);
3290 
3291 
3292 /*
3293  * Verify the fitness of task @p to run on @cpu taking into account the
3294  * CPU original capacity and the runtime/deadline ratio of the task.
3295  *
3296  * The function will return true if the original capacity of @cpu is
3297  * greater than or equal to task's deadline density right shifted by
3298  * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise.
3299  */
dl_task_fits_capacity(struct task_struct * p,int cpu)3300 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
3301 {
3302 	unsigned long cap = arch_scale_cpu_capacity(cpu);
3303 
3304 	return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT);
3305 }
3306 
cpu_bw_dl(struct rq * rq)3307 static inline unsigned long cpu_bw_dl(struct rq *rq)
3308 {
3309 	return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
3310 }
3311 
cpu_util_dl(struct rq * rq)3312 static inline unsigned long cpu_util_dl(struct rq *rq)
3313 {
3314 	return READ_ONCE(rq->avg_dl.util_avg);
3315 }
3316 
3317 
3318 extern unsigned long cpu_util_cfs(int cpu);
3319 extern unsigned long cpu_util_cfs_boost(int cpu);
3320 
cpu_util_rt(struct rq * rq)3321 static inline unsigned long cpu_util_rt(struct rq *rq)
3322 {
3323 	return READ_ONCE(rq->avg_rt.util_avg);
3324 }
3325 
3326 #else /* !CONFIG_SMP */
update_other_load_avgs(struct rq * rq)3327 static inline bool update_other_load_avgs(struct rq *rq) { return false; }
3328 #endif /* CONFIG_SMP */
3329 
3330 #ifdef CONFIG_UCLAMP_TASK
3331 
3332 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
3333 
uclamp_rq_get(struct rq * rq,enum uclamp_id clamp_id)3334 static inline unsigned long uclamp_rq_get(struct rq *rq,
3335 					  enum uclamp_id clamp_id)
3336 {
3337 	return READ_ONCE(rq->uclamp[clamp_id].value);
3338 }
3339 
uclamp_rq_set(struct rq * rq,enum uclamp_id clamp_id,unsigned int value)3340 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id,
3341 				 unsigned int value)
3342 {
3343 	WRITE_ONCE(rq->uclamp[clamp_id].value, value);
3344 }
3345 
uclamp_rq_is_idle(struct rq * rq)3346 static inline bool uclamp_rq_is_idle(struct rq *rq)
3347 {
3348 	return rq->uclamp_flags & UCLAMP_FLAG_IDLE;
3349 }
3350 
3351 /* Is the rq being capped/throttled by uclamp_max? */
uclamp_rq_is_capped(struct rq * rq)3352 static inline bool uclamp_rq_is_capped(struct rq *rq)
3353 {
3354 	unsigned long rq_util;
3355 	unsigned long max_util;
3356 
3357 	if (!static_branch_likely(&sched_uclamp_used))
3358 		return false;
3359 
3360 	rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq);
3361 	max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
3362 
3363 	return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util;
3364 }
3365 
3366 /*
3367  * When uclamp is compiled in, the aggregation at rq level is 'turned off'
3368  * by default in the fast path and only gets turned on once userspace performs
3369  * an operation that requires it.
3370  *
3371  * Returns true if userspace opted-in to use uclamp and aggregation at rq level
3372  * hence is active.
3373  */
uclamp_is_used(void)3374 static inline bool uclamp_is_used(void)
3375 {
3376 	return static_branch_likely(&sched_uclamp_used);
3377 }
3378 
3379 #define for_each_clamp_id(clamp_id) \
3380 	for ((clamp_id) = 0; (clamp_id) < UCLAMP_CNT; (clamp_id)++)
3381 
3382 extern unsigned int sysctl_sched_uclamp_util_min_rt_default;
3383 
3384 
uclamp_none(enum uclamp_id clamp_id)3385 static inline unsigned int uclamp_none(enum uclamp_id clamp_id)
3386 {
3387 	if (clamp_id == UCLAMP_MIN)
3388 		return 0;
3389 	return SCHED_CAPACITY_SCALE;
3390 }
3391 
3392 /* Integer rounded range for each bucket */
3393 #define UCLAMP_BUCKET_DELTA DIV_ROUND_CLOSEST(SCHED_CAPACITY_SCALE, UCLAMP_BUCKETS)
3394 
uclamp_bucket_id(unsigned int clamp_value)3395 static inline unsigned int uclamp_bucket_id(unsigned int clamp_value)
3396 {
3397 	return min_t(unsigned int, clamp_value / UCLAMP_BUCKET_DELTA, UCLAMP_BUCKETS - 1);
3398 }
3399 
3400 static inline void
uclamp_se_set(struct uclamp_se * uc_se,unsigned int value,bool user_defined)3401 uclamp_se_set(struct uclamp_se *uc_se, unsigned int value, bool user_defined)
3402 {
3403 	uc_se->value = value;
3404 	uc_se->bucket_id = uclamp_bucket_id(value);
3405 	uc_se->user_defined = user_defined;
3406 }
3407 
3408 #else /* !CONFIG_UCLAMP_TASK: */
3409 
3410 static inline unsigned long
uclamp_eff_value(struct task_struct * p,enum uclamp_id clamp_id)3411 uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id)
3412 {
3413 	if (clamp_id == UCLAMP_MIN)
3414 		return 0;
3415 
3416 	return SCHED_CAPACITY_SCALE;
3417 }
3418 
uclamp_rq_is_capped(struct rq * rq)3419 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; }
3420 
uclamp_is_used(void)3421 static inline bool uclamp_is_used(void)
3422 {
3423 	return false;
3424 }
3425 
3426 static inline unsigned long
uclamp_rq_get(struct rq * rq,enum uclamp_id clamp_id)3427 uclamp_rq_get(struct rq *rq, enum uclamp_id clamp_id)
3428 {
3429 	if (clamp_id == UCLAMP_MIN)
3430 		return 0;
3431 
3432 	return SCHED_CAPACITY_SCALE;
3433 }
3434 
3435 static inline void
uclamp_rq_set(struct rq * rq,enum uclamp_id clamp_id,unsigned int value)3436 uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, unsigned int value)
3437 {
3438 }
3439 
uclamp_rq_is_idle(struct rq * rq)3440 static inline bool uclamp_rq_is_idle(struct rq *rq)
3441 {
3442 	return false;
3443 }
3444 
3445 #endif /* !CONFIG_UCLAMP_TASK */
3446 
3447 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
3448 
cpu_util_irq(struct rq * rq)3449 static inline unsigned long cpu_util_irq(struct rq *rq)
3450 {
3451 	return READ_ONCE(rq->avg_irq.util_avg);
3452 }
3453 
3454 static inline
scale_irq_capacity(unsigned long util,unsigned long irq,unsigned long max)3455 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3456 {
3457 	util *= (max - irq);
3458 	util /= max;
3459 
3460 	return util;
3461 
3462 }
3463 
3464 #else /* !CONFIG_HAVE_SCHED_AVG_IRQ: */
3465 
cpu_util_irq(struct rq * rq)3466 static inline unsigned long cpu_util_irq(struct rq *rq)
3467 {
3468 	return 0;
3469 }
3470 
3471 static inline
scale_irq_capacity(unsigned long util,unsigned long irq,unsigned long max)3472 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3473 {
3474 	return util;
3475 }
3476 
3477 #endif /* !CONFIG_HAVE_SCHED_AVG_IRQ */
3478 
3479 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
3480 
3481 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
3482 
3483 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
3484 
sched_energy_enabled(void)3485 static inline bool sched_energy_enabled(void)
3486 {
3487 	return static_branch_unlikely(&sched_energy_present);
3488 }
3489 
3490 extern struct cpufreq_governor schedutil_gov;
3491 
3492 #else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
3493 
3494 #define perf_domain_span(pd) NULL
3495 
sched_energy_enabled(void)3496 static inline bool sched_energy_enabled(void) { return false; }
3497 
3498 #endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
3499 
3500 #ifdef CONFIG_MEMBARRIER
3501 
3502 /*
3503  * The scheduler provides memory barriers required by membarrier between:
3504  * - prior user-space memory accesses and store to rq->membarrier_state,
3505  * - store to rq->membarrier_state and following user-space memory accesses.
3506  * In the same way it provides those guarantees around store to rq->curr.
3507  */
membarrier_switch_mm(struct rq * rq,struct mm_struct * prev_mm,struct mm_struct * next_mm)3508 static inline void membarrier_switch_mm(struct rq *rq,
3509 					struct mm_struct *prev_mm,
3510 					struct mm_struct *next_mm)
3511 {
3512 	int membarrier_state;
3513 
3514 	if (prev_mm == next_mm)
3515 		return;
3516 
3517 	membarrier_state = atomic_read(&next_mm->membarrier_state);
3518 	if (READ_ONCE(rq->membarrier_state) == membarrier_state)
3519 		return;
3520 
3521 	WRITE_ONCE(rq->membarrier_state, membarrier_state);
3522 }
3523 
3524 #else /* !CONFIG_MEMBARRIER :*/
3525 
membarrier_switch_mm(struct rq * rq,struct mm_struct * prev_mm,struct mm_struct * next_mm)3526 static inline void membarrier_switch_mm(struct rq *rq,
3527 					struct mm_struct *prev_mm,
3528 					struct mm_struct *next_mm)
3529 {
3530 }
3531 
3532 #endif /* !CONFIG_MEMBARRIER */
3533 
3534 #ifdef CONFIG_SMP
is_per_cpu_kthread(struct task_struct * p)3535 static inline bool is_per_cpu_kthread(struct task_struct *p)
3536 {
3537 	if (!(p->flags & PF_KTHREAD))
3538 		return false;
3539 
3540 	if (p->nr_cpus_allowed != 1)
3541 		return false;
3542 
3543 	return true;
3544 }
3545 #endif
3546 
3547 extern void swake_up_all_locked(struct swait_queue_head *q);
3548 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
3549 
3550 extern int try_to_wake_up(struct task_struct *tsk, unsigned int state, int wake_flags);
3551 
3552 #ifdef CONFIG_PREEMPT_DYNAMIC
3553 extern int preempt_dynamic_mode;
3554 extern int sched_dynamic_mode(const char *str);
3555 extern void sched_dynamic_update(int mode);
3556 #endif
3557 
3558 #ifdef CONFIG_SCHED_MM_CID
3559 
3560 #define SCHED_MM_CID_PERIOD_NS	(100ULL * 1000000)	/* 100ms */
3561 #define MM_CID_SCAN_DELAY	100			/* 100ms */
3562 
3563 extern raw_spinlock_t cid_lock;
3564 extern int use_cid_lock;
3565 
3566 extern void sched_mm_cid_migrate_from(struct task_struct *t);
3567 extern void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t);
3568 extern void task_tick_mm_cid(struct rq *rq, struct task_struct *curr);
3569 extern void init_sched_mm_cid(struct task_struct *t);
3570 
__mm_cid_put(struct mm_struct * mm,int cid)3571 static inline void __mm_cid_put(struct mm_struct *mm, int cid)
3572 {
3573 	if (cid < 0)
3574 		return;
3575 	cpumask_clear_cpu(cid, mm_cidmask(mm));
3576 }
3577 
3578 /*
3579  * The per-mm/cpu cid can have the MM_CID_LAZY_PUT flag set or transition to
3580  * the MM_CID_UNSET state without holding the rq lock, but the rq lock needs to
3581  * be held to transition to other states.
3582  *
3583  * State transitions synchronized with cmpxchg or try_cmpxchg need to be
3584  * consistent across CPUs, which prevents use of this_cpu_cmpxchg.
3585  */
mm_cid_put_lazy(struct task_struct * t)3586 static inline void mm_cid_put_lazy(struct task_struct *t)
3587 {
3588 	struct mm_struct *mm = t->mm;
3589 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3590 	int cid;
3591 
3592 	lockdep_assert_irqs_disabled();
3593 	cid = __this_cpu_read(pcpu_cid->cid);
3594 	if (!mm_cid_is_lazy_put(cid) ||
3595 	    !try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET))
3596 		return;
3597 	__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3598 }
3599 
mm_cid_pcpu_unset(struct mm_struct * mm)3600 static inline int mm_cid_pcpu_unset(struct mm_struct *mm)
3601 {
3602 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3603 	int cid, res;
3604 
3605 	lockdep_assert_irqs_disabled();
3606 	cid = __this_cpu_read(pcpu_cid->cid);
3607 	for (;;) {
3608 		if (mm_cid_is_unset(cid))
3609 			return MM_CID_UNSET;
3610 		/*
3611 		 * Attempt transition from valid or lazy-put to unset.
3612 		 */
3613 		res = cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, cid, MM_CID_UNSET);
3614 		if (res == cid)
3615 			break;
3616 		cid = res;
3617 	}
3618 	return cid;
3619 }
3620 
mm_cid_put(struct mm_struct * mm)3621 static inline void mm_cid_put(struct mm_struct *mm)
3622 {
3623 	int cid;
3624 
3625 	lockdep_assert_irqs_disabled();
3626 	cid = mm_cid_pcpu_unset(mm);
3627 	if (cid == MM_CID_UNSET)
3628 		return;
3629 	__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3630 }
3631 
__mm_cid_try_get(struct mm_struct * mm)3632 static inline int __mm_cid_try_get(struct mm_struct *mm)
3633 {
3634 	struct cpumask *cpumask;
3635 	int cid;
3636 
3637 	cpumask = mm_cidmask(mm);
3638 	/*
3639 	 * Retry finding first zero bit if the mask is temporarily
3640 	 * filled. This only happens during concurrent remote-clear
3641 	 * which owns a cid without holding a rq lock.
3642 	 */
3643 	for (;;) {
3644 		cid = cpumask_first_zero(cpumask);
3645 		if (cid < nr_cpu_ids)
3646 			break;
3647 		cpu_relax();
3648 	}
3649 	if (cpumask_test_and_set_cpu(cid, cpumask))
3650 		return -1;
3651 
3652 	return cid;
3653 }
3654 
3655 /*
3656  * Save a snapshot of the current runqueue time of this cpu
3657  * with the per-cpu cid value, allowing to estimate how recently it was used.
3658  */
mm_cid_snapshot_time(struct rq * rq,struct mm_struct * mm)3659 static inline void mm_cid_snapshot_time(struct rq *rq, struct mm_struct *mm)
3660 {
3661 	struct mm_cid *pcpu_cid = per_cpu_ptr(mm->pcpu_cid, cpu_of(rq));
3662 
3663 	lockdep_assert_rq_held(rq);
3664 	WRITE_ONCE(pcpu_cid->time, rq->clock);
3665 }
3666 
__mm_cid_get(struct rq * rq,struct mm_struct * mm)3667 static inline int __mm_cid_get(struct rq *rq, struct mm_struct *mm)
3668 {
3669 	int cid;
3670 
3671 	/*
3672 	 * All allocations (even those using the cid_lock) are lock-free. If
3673 	 * use_cid_lock is set, hold the cid_lock to perform cid allocation to
3674 	 * guarantee forward progress.
3675 	 */
3676 	if (!READ_ONCE(use_cid_lock)) {
3677 		cid = __mm_cid_try_get(mm);
3678 		if (cid >= 0)
3679 			goto end;
3680 		raw_spin_lock(&cid_lock);
3681 	} else {
3682 		raw_spin_lock(&cid_lock);
3683 		cid = __mm_cid_try_get(mm);
3684 		if (cid >= 0)
3685 			goto unlock;
3686 	}
3687 
3688 	/*
3689 	 * cid concurrently allocated. Retry while forcing following
3690 	 * allocations to use the cid_lock to ensure forward progress.
3691 	 */
3692 	WRITE_ONCE(use_cid_lock, 1);
3693 	/*
3694 	 * Set use_cid_lock before allocation. Only care about program order
3695 	 * because this is only required for forward progress.
3696 	 */
3697 	barrier();
3698 	/*
3699 	 * Retry until it succeeds. It is guaranteed to eventually succeed once
3700 	 * all newcoming allocations observe the use_cid_lock flag set.
3701 	 */
3702 	do {
3703 		cid = __mm_cid_try_get(mm);
3704 		cpu_relax();
3705 	} while (cid < 0);
3706 	/*
3707 	 * Allocate before clearing use_cid_lock. Only care about
3708 	 * program order because this is for forward progress.
3709 	 */
3710 	barrier();
3711 	WRITE_ONCE(use_cid_lock, 0);
3712 unlock:
3713 	raw_spin_unlock(&cid_lock);
3714 end:
3715 	mm_cid_snapshot_time(rq, mm);
3716 
3717 	return cid;
3718 }
3719 
mm_cid_get(struct rq * rq,struct mm_struct * mm)3720 static inline int mm_cid_get(struct rq *rq, struct mm_struct *mm)
3721 {
3722 	struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3723 	struct cpumask *cpumask;
3724 	int cid;
3725 
3726 	lockdep_assert_rq_held(rq);
3727 	cpumask = mm_cidmask(mm);
3728 	cid = __this_cpu_read(pcpu_cid->cid);
3729 	if (mm_cid_is_valid(cid)) {
3730 		mm_cid_snapshot_time(rq, mm);
3731 		return cid;
3732 	}
3733 	if (mm_cid_is_lazy_put(cid)) {
3734 		if (try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET))
3735 			__mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3736 	}
3737 	cid = __mm_cid_get(rq, mm);
3738 	__this_cpu_write(pcpu_cid->cid, cid);
3739 
3740 	return cid;
3741 }
3742 
switch_mm_cid(struct rq * rq,struct task_struct * prev,struct task_struct * next)3743 static inline void switch_mm_cid(struct rq *rq,
3744 				 struct task_struct *prev,
3745 				 struct task_struct *next)
3746 {
3747 	/*
3748 	 * Provide a memory barrier between rq->curr store and load of
3749 	 * {prev,next}->mm->pcpu_cid[cpu] on rq->curr->mm transition.
3750 	 *
3751 	 * Should be adapted if context_switch() is modified.
3752 	 */
3753 	if (!next->mm) {                                // to kernel
3754 		/*
3755 		 * user -> kernel transition does not guarantee a barrier, but
3756 		 * we can use the fact that it performs an atomic operation in
3757 		 * mmgrab().
3758 		 */
3759 		if (prev->mm)                           // from user
3760 			smp_mb__after_mmgrab();
3761 		/*
3762 		 * kernel -> kernel transition does not change rq->curr->mm
3763 		 * state. It stays NULL.
3764 		 */
3765 	} else {                                        // to user
3766 		/*
3767 		 * kernel -> user transition does not provide a barrier
3768 		 * between rq->curr store and load of {prev,next}->mm->pcpu_cid[cpu].
3769 		 * Provide it here.
3770 		 */
3771 		if (!prev->mm) {                        // from kernel
3772 			smp_mb();
3773 		} else {				// from user
3774 			/*
3775 			 * user->user transition relies on an implicit
3776 			 * memory barrier in switch_mm() when
3777 			 * current->mm changes. If the architecture
3778 			 * switch_mm() does not have an implicit memory
3779 			 * barrier, it is emitted here.  If current->mm
3780 			 * is unchanged, no barrier is needed.
3781 			 */
3782 			smp_mb__after_switch_mm();
3783 		}
3784 	}
3785 	if (prev->mm_cid_active) {
3786 		mm_cid_snapshot_time(rq, prev->mm);
3787 		mm_cid_put_lazy(prev);
3788 		prev->mm_cid = -1;
3789 	}
3790 	if (next->mm_cid_active)
3791 		next->last_mm_cid = next->mm_cid = mm_cid_get(rq, next->mm);
3792 }
3793 
3794 #else /* !CONFIG_SCHED_MM_CID: */
switch_mm_cid(struct rq * rq,struct task_struct * prev,struct task_struct * next)3795 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)3796 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)3797 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)3798 static inline void task_tick_mm_cid(struct rq *rq, struct task_struct *curr) { }
init_sched_mm_cid(struct task_struct * t)3799 static inline void init_sched_mm_cid(struct task_struct *t) { }
3800 #endif /* !CONFIG_SCHED_MM_CID */
3801 
3802 extern u64 avg_vruntime(struct cfs_rq *cfs_rq);
3803 extern int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se);
3804 
3805 #ifdef CONFIG_RT_MUTEXES
3806 
__rt_effective_prio(struct task_struct * pi_task,int prio)3807 static inline int __rt_effective_prio(struct task_struct *pi_task, int prio)
3808 {
3809 	if (pi_task)
3810 		prio = min(prio, pi_task->prio);
3811 
3812 	return prio;
3813 }
3814 
rt_effective_prio(struct task_struct * p,int prio)3815 static inline int rt_effective_prio(struct task_struct *p, int prio)
3816 {
3817 	struct task_struct *pi_task = rt_mutex_get_top_task(p);
3818 
3819 	return __rt_effective_prio(pi_task, prio);
3820 }
3821 
3822 #else /* !CONFIG_RT_MUTEXES: */
3823 
rt_effective_prio(struct task_struct * p,int prio)3824 static inline int rt_effective_prio(struct task_struct *p, int prio)
3825 {
3826 	return prio;
3827 }
3828 
3829 #endif /* !CONFIG_RT_MUTEXES */
3830 
3831 extern int __sched_setscheduler(struct task_struct *p, const struct sched_attr *attr, bool user, bool pi);
3832 extern int __sched_setaffinity(struct task_struct *p, struct affinity_context *ctx);
3833 extern const struct sched_class *__setscheduler_class(int policy, int prio);
3834 extern void set_load_weight(struct task_struct *p, bool update_load);
3835 extern void enqueue_task(struct rq *rq, struct task_struct *p, int flags);
3836 extern bool dequeue_task(struct rq *rq, struct task_struct *p, int flags);
3837 
3838 extern void check_class_changing(struct rq *rq, struct task_struct *p,
3839 				 const struct sched_class *prev_class);
3840 extern void check_class_changed(struct rq *rq, struct task_struct *p,
3841 				const struct sched_class *prev_class,
3842 				int oldprio);
3843 
3844 #ifdef CONFIG_SMP
3845 extern struct balance_callback *splice_balance_callbacks(struct rq *rq);
3846 extern void balance_callbacks(struct rq *rq, struct balance_callback *head);
3847 #else
3848 
splice_balance_callbacks(struct rq * rq)3849 static inline struct balance_callback *splice_balance_callbacks(struct rq *rq)
3850 {
3851 	return NULL;
3852 }
3853 
balance_callbacks(struct rq * rq,struct balance_callback * head)3854 static inline void balance_callbacks(struct rq *rq, struct balance_callback *head)
3855 {
3856 }
3857 
3858 #endif
3859 
3860 #ifdef CONFIG_SCHED_CLASS_EXT
3861 /*
3862  * Used by SCX in the enable/disable paths to move tasks between sched_classes
3863  * and establish invariants.
3864  */
3865 struct sched_enq_and_set_ctx {
3866 	struct task_struct	*p;
3867 	int			queue_flags;
3868 	bool			queued;
3869 	bool			running;
3870 };
3871 
3872 void sched_deq_and_put_task(struct task_struct *p, int queue_flags,
3873 			    struct sched_enq_and_set_ctx *ctx);
3874 void sched_enq_and_set_task(struct sched_enq_and_set_ctx *ctx);
3875 
3876 #endif /* CONFIG_SCHED_CLASS_EXT */
3877 
3878 #include "ext.h"
3879 
3880 #endif /* _KERNEL_SCHED_SCHED_H */
3881