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