xref: /linux/kernel/sched/sched.h (revision 11260c335ec6071af5543aef73000b28f041c124)
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/prandom.h>
9 #include <linux/sched/affinity.h>
10 #include <linux/sched/autogroup.h>
11 #include <linux/sched/cpufreq.h>
12 #include <linux/sched/deadline.h>
13 #include <linux/sched.h>
14 #include <linux/sched/loadavg.h>
15 #include <linux/sched/mm.h>
16 #include <linux/sched/rseq_api.h>
17 #include <linux/sched/signal.h>
18 #include <linux/sched/smt.h>
19 #include <linux/sched/stat.h>
20 #include <linux/sched/sysctl.h>
21 #include <linux/sched/task_flags.h>
22 #include <linux/sched/task.h>
23 #include <linux/sched/topology.h>
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/cpuset.h>
34 #include <linux/ctype.h>
35 #include <linux/file.h>
36 #include <linux/fs_api.h>
37 #include <linux/hrtimer_api.h>
38 #include <linux/interrupt.h>
39 #include <linux/irq_work.h>
40 #include <linux/jiffies.h>
41 #include <linux/kref_api.h>
42 #include <linux/kthread.h>
43 #include <linux/ktime_api.h>
44 #include <linux/lockdep_api.h>
45 #include <linux/lockdep.h>
46 #include <linux/memblock.h>
47 #include <linux/memcontrol.h>
48 #include <linux/minmax.h>
49 #include <linux/mm.h>
50 #include <linux/module.h>
51 #include <linux/mutex_api.h>
52 #include <linux/plist.h>
53 #include <linux/poll.h>
54 #include <linux/proc_fs.h>
55 #include <linux/profile.h>
56 #include <linux/psi.h>
57 #include <linux/rcupdate.h>
58 #include <linux/seq_file.h>
59 #include <linux/seqlock.h>
60 #include <linux/softirq.h>
61 #include <linux/spinlock_api.h>
62 #include <linux/static_key.h>
63 #include <linux/stop_machine.h>
64 #include <linux/syscalls_api.h>
65 #include <linux/syscalls.h>
66 #include <linux/tick.h>
67 #include <linux/topology.h>
68 #include <linux/types.h>
69 #include <linux/u64_stats_sync_api.h>
70 #include <linux/uaccess.h>
71 #include <linux/vmstat.h>
72 #include <linux/wait_api.h>
73 #include <linux/wait_bit.h>
74 #include <linux/workqueue_api.h>
75 #include <linux/delayacct.h>
76 #include <linux/mmu_context.h>
77 
78 #include <trace/events/power.h>
79 #include <trace/events/sched.h>
80 
81 #include "../workqueue_internal.h"
82 
83 struct rq;
84 struct cfs_rq;
85 struct rt_rq;
86 struct sched_group;
87 struct cpuidle_state;
88 
89 #if defined(CONFIG_PARAVIRT) && !defined(CONFIG_HAVE_PV_STEAL_CLOCK_GEN)
90 # include <asm/paravirt.h>
91 #endif
92 
93 #include <asm/barrier.h>
94 
95 #include "cpupri.h"
96 #include "cpudeadline.h"
97 
98 /* task_struct::on_rq states: */
99 #define TASK_ON_RQ_QUEUED	1
100 #define TASK_ON_RQ_MIGRATING	2
101 
102 extern __read_mostly int scheduler_running;
103 
104 extern unsigned long calc_load_update;
105 extern atomic_long_t calc_load_tasks;
106 
107 extern void calc_global_load_tick(struct rq *this_rq);
108 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
109 
110 extern void call_trace_sched_update_nr_running(struct rq *rq, int count);
111 
112 extern int sysctl_sched_rt_period;
113 extern int sysctl_sched_rt_runtime;
114 extern int sched_rr_timeslice;
115 
116 /*
117  * Asymmetric CPU capacity bits
118  */
119 struct asym_cap_data {
120 	struct list_head link;
121 	struct rcu_head rcu;
122 	unsigned long capacity;
123 	unsigned long cpus[];
124 };
125 
126 extern struct list_head asym_cap_list;
127 
128 #define cpu_capacity_span(asym_data) to_cpumask((asym_data)->cpus)
129 
130 /*
131  * Helpers for converting nanosecond timing to jiffy resolution
132  */
133 #define NS_TO_JIFFIES(time)	((unsigned long)(time) / (NSEC_PER_SEC/HZ))
134 
135 /*
136  * Increase resolution of nice-level calculations for 64-bit architectures.
137  * The extra resolution improves shares distribution and load balancing of
138  * low-weight task groups (eg. nice +19 on an autogroup), deeper task-group
139  * hierarchies, especially on larger systems. This is not a user-visible change
140  * and does not change the user-interface for setting shares/weights.
141  *
142  * We increase resolution only if we have enough bits to allow this increased
143  * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
144  * are pretty high and the returns do not justify the increased costs.
145  *
146  * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
147  * increase coverage and consistency always enable it on 64-bit platforms.
148  */
149 #ifdef CONFIG_64BIT
150 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
151 # define scale_load(w)		((w) << SCHED_FIXEDPOINT_SHIFT)
152 # define scale_load_down(w)					\
153 ({								\
154 	unsigned long __w = (w);				\
155 								\
156 	if (__w)						\
157 		__w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT);	\
158 	__w;							\
159 })
160 #else
161 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT)
162 # define scale_load(w)		(w)
163 # define scale_load_down(w)	(w)
164 #endif
165 
166 /*
167  * Task weight (visible to users) and its load (invisible to users) have
168  * independent resolution, but they should be well calibrated. We use
169  * scale_load() and scale_load_down(w) to convert between them. The
170  * following must be true:
171  *
172  *  scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD
173  *
174  */
175 #define NICE_0_LOAD		(1L << NICE_0_LOAD_SHIFT)
176 
177 /*
178  * Single value that decides SCHED_DEADLINE internal math precision.
179  * 10 -> just above 1us
180  * 9  -> just above 0.5us
181  */
182 #define DL_SCALE		10
183 
184 /*
185  * Single value that denotes runtime == period, ie unlimited time.
186  */
187 #define RUNTIME_INF		((u64)~0ULL)
188 
idle_policy(int policy)189 static inline int idle_policy(int policy)
190 {
191 	return policy == SCHED_IDLE;
192 }
193 
normal_policy(int policy)194 static inline int normal_policy(int policy)
195 {
196 #ifdef CONFIG_SCHED_CLASS_EXT
197 	if (policy == SCHED_EXT)
198 		return true;
199 #endif
200 	return policy == SCHED_NORMAL;
201 }
202 
fair_policy(int policy)203 static inline int fair_policy(int policy)
204 {
205 	return normal_policy(policy) || policy == SCHED_BATCH;
206 }
207 
rt_policy(int policy)208 static inline int rt_policy(int policy)
209 {
210 	return policy == SCHED_FIFO || policy == SCHED_RR;
211 }
212 
dl_policy(int policy)213 static inline int dl_policy(int policy)
214 {
215 	return policy == SCHED_DEADLINE;
216 }
217 
valid_policy(int policy)218 static inline bool valid_policy(int policy)
219 {
220 	return idle_policy(policy) || fair_policy(policy) ||
221 		rt_policy(policy) || dl_policy(policy);
222 }
223 
task_has_idle_policy(struct task_struct * p)224 static inline int task_has_idle_policy(struct task_struct *p)
225 {
226 	return idle_policy(p->policy);
227 }
228 
task_has_rt_policy(struct task_struct * p)229 static inline int task_has_rt_policy(struct task_struct *p)
230 {
231 	return rt_policy(p->policy);
232 }
233 
task_has_dl_policy(struct task_struct * p)234 static inline int task_has_dl_policy(struct task_struct *p)
235 {
236 	return dl_policy(p->policy);
237 }
238 
239 #define cap_scale(v, s)		((v)*(s) >> SCHED_CAPACITY_SHIFT)
240 
update_avg(u64 * avg,u64 sample)241 static inline void update_avg(u64 *avg, u64 sample)
242 {
243 	s64 diff = sample - *avg;
244 
245 	*avg += diff / 8;
246 }
247 
248 /*
249  * Shifting a value by an exponent greater *or equal* to the size of said value
250  * is UB; cap at size-1.
251  */
252 #define shr_bound(val, shift)							\
253 	(val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1))
254 
255 /*
256  * cgroup weight knobs should use the common MIN, DFL and MAX values which are
257  * 1, 100 and 10000 respectively. While it loses a bit of range on both ends, it
258  * maps pretty well onto the shares value used by scheduler and the round-trip
259  * conversions preserve the original value over the entire range.
260  */
sched_weight_from_cgroup(unsigned long cgrp_weight)261 static inline unsigned long sched_weight_from_cgroup(unsigned long cgrp_weight)
262 {
263 	return DIV_ROUND_CLOSEST_ULL(cgrp_weight * 1024, CGROUP_WEIGHT_DFL);
264 }
265 
sched_weight_to_cgroup(unsigned long weight)266 static inline unsigned long sched_weight_to_cgroup(unsigned long weight)
267 {
268 	return clamp_t(unsigned long,
269 		       DIV_ROUND_CLOSEST_ULL(weight * CGROUP_WEIGHT_DFL, 1024),
270 		       CGROUP_WEIGHT_MIN, CGROUP_WEIGHT_MAX);
271 }
272 
273 /*
274  * !! For sched_setattr_nocheck() (kernel) only !!
275  *
276  * This is actually gross. :(
277  *
278  * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
279  * tasks, but still be able to sleep. We need this on platforms that cannot
280  * atomically change clock frequency. Remove once fast switching will be
281  * available on such platforms.
282  *
283  * SUGOV stands for SchedUtil GOVernor.
284  */
285 #define SCHED_FLAG_SUGOV	0x10000000
286 
287 #define SCHED_DL_FLAGS		(SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV)
288 
dl_entity_is_special(const struct sched_dl_entity * dl_se)289 static inline bool dl_entity_is_special(const struct sched_dl_entity *dl_se)
290 {
291 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
292 	return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
293 #else
294 	return false;
295 #endif
296 }
297 
298 /*
299  * Tells if entity @a should preempt entity @b.
300  */
dl_entity_preempt(const struct sched_dl_entity * a,const struct sched_dl_entity * b)301 static inline bool dl_entity_preempt(const struct sched_dl_entity *a,
302 				     const struct sched_dl_entity *b)
303 {
304 	return dl_entity_is_special(a) ||
305 	       dl_time_before(a->deadline, b->deadline);
306 }
307 
308 /*
309  * This is the priority-queue data structure of the RT scheduling class:
310  */
311 struct rt_prio_array {
312 	DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
313 	struct list_head queue[MAX_RT_PRIO];
314 };
315 
316 struct rt_bandwidth {
317 	/* nests inside the rq lock: */
318 	raw_spinlock_t		rt_runtime_lock;
319 	ktime_t			rt_period;
320 	u64			rt_runtime;
321 	struct hrtimer		rt_period_timer;
322 	unsigned int		rt_period_active;
323 };
324 
dl_bandwidth_enabled(void)325 static inline int dl_bandwidth_enabled(void)
326 {
327 	return sysctl_sched_rt_runtime >= 0;
328 }
329 
330 /*
331  * To keep the bandwidth of -deadline tasks under control
332  * we need some place where:
333  *  - store the maximum -deadline bandwidth of each cpu;
334  *  - cache the fraction of bandwidth that is currently allocated in
335  *    each root domain;
336  *
337  * This is all done in the data structure below. It is similar to the
338  * one used for RT-throttling (rt_bandwidth), with the main difference
339  * that, since here we are only interested in admission control, we
340  * do not decrease any runtime while the group "executes", neither we
341  * need a timer to replenish it.
342  *
343  * With respect to SMP, bandwidth is given on a per root domain basis,
344  * meaning that:
345  *  - bw (< 100%) is the deadline bandwidth of each CPU;
346  *  - total_bw is the currently allocated bandwidth in each root domain;
347  */
348 struct dl_bw {
349 	raw_spinlock_t		lock;
350 	u64			bw;
351 	u64			total_bw;
352 };
353 
354 extern void init_dl_bw(struct dl_bw *dl_b);
355 extern int  sched_dl_global_validate(void);
356 extern void sched_dl_do_global(void);
357 extern int  sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
358 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
359 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr, unsigned int flags);
360 extern bool __checkparam_dl(const struct sched_attr *attr);
361 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
362 extern int  dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
363 extern int  dl_bw_deactivate(int cpu);
364 extern s64 dl_scaled_delta_exec(struct rq *rq, struct sched_dl_entity *dl_se, s64 delta_exec);
365 /*
366  * SCHED_DEADLINE supports servers (nested scheduling) with the following
367  * interface:
368  *
369  *   dl_se::rq -- runqueue we belong to.
370  *
371  *   dl_se::server_pick() -- nested pick_next_task(); we yield the period if this
372  *                           returns NULL.
373  *
374  *   dl_server_update() -- called from update_curr_common(), propagates runtime
375  *                         to the server.
376  *
377  *   dl_server_start() -- start the server when it has tasks; it will stop
378  *			  automatically when there are no more tasks, per
379  *			  dl_se::server_pick() returning NULL.
380  *
381  *   dl_server_stop() -- (force) stop the server; use when updating
382  *                       parameters.
383  *
384  *   dl_server_init() -- initializes the server.
385  *
386  * When started the dl_server will (per dl_defer) schedule a timer for its
387  * zero-laxity point -- that is, unlike regular EDF tasks which run ASAP, a
388  * server will run at the very end of its period.
389  *
390  * This is done such that any runtime from the target class can be accounted
391  * against the server -- through dl_server_update() above -- such that when it
392  * becomes time to run, it might already be out of runtime and get deferred
393  * until the next period. In this case dl_server_timer() will alternate
394  * between defer and replenish but never actually enqueue the server.
395  *
396  * Only when the target class does not manage to exhaust the server's runtime
397  * (there's actualy starvation in the given period), will the dl_server get on
398  * the runqueue. Once queued it will pick tasks from the target class and run
399  * them until either its runtime is exhaused, at which point its back to
400  * dl_server_timer, or until there are no more tasks to run, at which point
401  * the dl_server stops itself.
402  *
403  * By stopping at this point the dl_server retains bandwidth, which, if a new
404  * task wakes up imminently (starting the server again), can be used --
405  * subject to CBS wakeup rules -- without having to wait for the next period.
406  *
407  * Additionally, because of the dl_defer behaviour the start/stop behaviour is
408  * naturally thottled to once per period, avoiding high context switch
409  * workloads from spamming the hrtimer program/cancel paths.
410  */
411 extern void dl_server_update_idle(struct sched_dl_entity *dl_se, s64 delta_exec);
412 extern void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec);
413 extern void dl_server_start(struct sched_dl_entity *dl_se);
414 extern void dl_server_stop(struct sched_dl_entity *dl_se);
415 extern void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq,
416 		    dl_server_pick_f pick_task);
417 extern void sched_init_dl_servers(void);
418 
419 extern void fair_server_init(struct rq *rq);
420 extern void ext_server_init(struct rq *rq);
421 extern void __dl_server_attach_root(struct sched_dl_entity *dl_se, struct rq *rq);
422 extern int dl_server_apply_params(struct sched_dl_entity *dl_se,
423 		    u64 runtime, u64 period, bool init);
424 extern int dl_server_attach_bw(struct sched_dl_entity *dl_se);
425 extern void dl_server_detach_bw(struct sched_dl_entity *dl_se);
426 extern int dl_server_swap_bw(struct sched_dl_entity *detach_se,
427 			     struct sched_dl_entity *attach_se);
428 
dl_server_active(struct sched_dl_entity * dl_se)429 static inline bool dl_server_active(struct sched_dl_entity *dl_se)
430 {
431 	return dl_se->dl_server_active;
432 }
433 
434 #ifdef CONFIG_CGROUP_SCHED
435 
436 extern struct list_head task_groups;
437 
438 #ifdef CONFIG_GROUP_SCHED_BANDWIDTH
439 extern const u64 max_bw_quota_period_us;
440 
441 /*
442  * default period for group bandwidth.
443  * default: 0.1s, units: microseconds
444  */
default_bw_period_us(void)445 static inline u64 default_bw_period_us(void)
446 {
447 	return 100000ULL;
448 }
449 #endif /* CONFIG_GROUP_SCHED_BANDWIDTH */
450 
451 struct cfs_bandwidth {
452 #ifdef CONFIG_CFS_BANDWIDTH
453 	raw_spinlock_t		lock;
454 	ktime_t			period;
455 	u64			quota;
456 	u64			runtime;
457 	u64			burst;
458 	u64			runtime_snap;
459 	s64			hierarchical_quota;
460 
461 	u8			idle;
462 	u8			period_active;
463 	u8			slack_started;
464 	struct hrtimer		period_timer;
465 	struct hrtimer		slack_timer;
466 	struct list_head	throttled_cfs_rq;
467 
468 	/* Statistics: */
469 	int			nr_periods;
470 	int			nr_throttled;
471 	int			nr_burst;
472 	u64			throttled_time;
473 	u64			burst_time;
474 #endif /* CONFIG_CFS_BANDWIDTH */
475 };
476 
477 /* Task group related information */
478 struct task_group {
479 	struct cgroup_subsys_state css;
480 
481 #ifdef CONFIG_GROUP_SCHED_WEIGHT
482 	/* A positive value indicates that this is a SCHED_IDLE group. */
483 	int			idle;
484 #endif
485 
486 #ifdef CONFIG_FAIR_GROUP_SCHED
487 	/* runqueue "owned" by this group on each CPU */
488 	struct cfs_rq __percpu	*cfs_rq;
489 	unsigned long		shares;
490 	/*
491 	 * load_avg can be heavily contended at clock tick time, so put
492 	 * it in its own cache-line separated from the fields above which
493 	 * will also be accessed at each tick.
494 	 */
495 	atomic_long_t		load_avg ____cacheline_aligned;
496 	atomic_long_t		runnable_avg;
497 
498 #endif /* CONFIG_FAIR_GROUP_SCHED */
499 
500 #ifdef CONFIG_RT_GROUP_SCHED
501 	struct sched_rt_entity	**rt_se;
502 	struct rt_rq		**rt_rq;
503 
504 	struct rt_bandwidth	rt_bandwidth;
505 #endif
506 
507 	struct scx_task_group	scx;
508 
509 	struct rcu_head		rcu;
510 	struct list_head	list;
511 
512 	struct task_group	*parent;
513 	struct list_head	siblings;
514 	struct list_head	children;
515 
516 #ifdef CONFIG_SCHED_AUTOGROUP
517 	struct autogroup	*autogroup;
518 #endif
519 
520 	struct cfs_bandwidth	cfs_bandwidth;
521 
522 #ifdef CONFIG_UCLAMP_TASK_GROUP
523 	/* The two decimal precision [%] value requested from user-space */
524 	unsigned int		uclamp_pct[UCLAMP_CNT];
525 	/* Clamp values requested for a task group */
526 	struct uclamp_se	uclamp_req[UCLAMP_CNT];
527 	/* Effective clamp values used for a task group */
528 	struct uclamp_se	uclamp[UCLAMP_CNT];
529 #endif
530 
531 };
532 
533 #define ROOT_TASK_GROUP_LOAD	NICE_0_LOAD
534 
535 typedef int (*tg_visitor)(struct task_group *, void *);
536 
537 extern int walk_tg_tree_from(struct task_group *from,
538 			     tg_visitor down, tg_visitor up, void *data);
539 
540 /*
541  * Iterate the full tree, calling @down when first entering a node and @up when
542  * leaving it for the final time.
543  *
544  * Caller must hold rcu_lock or sufficient equivalent.
545  */
walk_tg_tree(tg_visitor down,tg_visitor up,void * data)546 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
547 {
548 	return walk_tg_tree_from(&root_task_group, down, up, data);
549 }
550 
css_tg(struct cgroup_subsys_state * css)551 static inline struct task_group *css_tg(struct cgroup_subsys_state *css)
552 {
553 	return css ? container_of(css, struct task_group, css) : NULL;
554 }
555 
556 extern int tg_nop(struct task_group *tg, void *data);
557 
558 #ifdef CONFIG_FAIR_GROUP_SCHED
559 extern void free_fair_sched_group(struct task_group *tg);
560 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
561 extern void online_fair_sched_group(struct task_group *tg);
562 extern void unregister_fair_sched_group(struct task_group *tg);
563 extern void __sched_cgroup_mode_update(int mode);
564 #else /* !CONFIG_FAIR_GROUP_SCHED: */
free_fair_sched_group(struct task_group * tg)565 static inline void free_fair_sched_group(struct task_group *tg) { }
alloc_fair_sched_group(struct task_group * tg,struct task_group * parent)566 static inline int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
567 {
568        return 1;
569 }
online_fair_sched_group(struct task_group * tg)570 static inline void online_fair_sched_group(struct task_group *tg) { }
unregister_fair_sched_group(struct task_group * tg)571 static inline void unregister_fair_sched_group(struct task_group *tg) { }
572 #endif /* !CONFIG_FAIR_GROUP_SCHED */
573 
574 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
575 			struct sched_entity *se, int cpu,
576 			struct sched_entity *parent);
577 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b, struct cfs_bandwidth *parent);
578 
579 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
580 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
581 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
582 extern bool cfs_task_bw_constrained(struct task_struct *p);
583 
584 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
585 		struct sched_rt_entity *rt_se, int cpu,
586 		struct sched_rt_entity *parent);
587 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
588 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
589 extern long sched_group_rt_runtime(struct task_group *tg);
590 extern long sched_group_rt_period(struct task_group *tg);
591 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
592 
593 extern struct task_group *sched_create_group(struct task_group *parent);
594 extern void sched_online_group(struct task_group *tg,
595 			       struct task_group *parent);
596 extern void sched_destroy_group(struct task_group *tg);
597 extern void sched_release_group(struct task_group *tg);
598 
599 extern void sched_move_task(struct task_struct *tsk, bool for_autogroup);
600 
601 #ifdef CONFIG_FAIR_GROUP_SCHED
602 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
603 
604 extern int sched_group_set_idle(struct task_group *tg, long idle);
605 
606 extern void set_task_rq_fair(struct sched_entity *se,
607 			     struct cfs_rq *prev, struct cfs_rq *next);
608 #else /* !CONFIG_FAIR_GROUP_SCHED: */
sched_group_set_shares(struct task_group * tg,unsigned long shares)609 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)610 static inline int sched_group_set_idle(struct task_group *tg, long idle) { return 0; }
611 #endif /* !CONFIG_FAIR_GROUP_SCHED */
612 
613 #else /* !CONFIG_CGROUP_SCHED: */
614 
615 struct cfs_bandwidth { };
616 
cfs_task_bw_constrained(struct task_struct * p)617 static inline bool cfs_task_bw_constrained(struct task_struct *p) { return false; }
618 
619 #endif /* !CONFIG_CGROUP_SCHED */
620 
621 /*
622  * A weight of 0 or 1 can cause arithmetics problems.
623  * A weight of a cfs_rq is the sum of weights of which entities
624  * are queued on this cfs_rq, so a weight of a entity should not be
625  * too large, so as the shares value of a task group.
626  * (The default weight is 1024 - so there's no practical
627  *  limitation from this.)
628  */
629 #define MIN_SHARES		(1UL <<  1)
630 #define MAX_SHARES		(1UL << 18)
631 
632 extern void unregister_rt_sched_group(struct task_group *tg);
633 extern void free_rt_sched_group(struct task_group *tg);
634 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
635 
636 /*
637  * u64_u32_load/u64_u32_store
638  *
639  * Use a copy of a u64 value to protect against data race. This is only
640  * applicable for 32-bits architectures.
641  */
642 #ifdef CONFIG_64BIT
643 # define u64_u32_load_copy(var, copy)		var
644 # define u64_u32_store_copy(var, copy, val)	(var = val)
645 #else
646 # define u64_u32_load_copy(var, copy)					\
647 ({									\
648 	u64 __val, __val_copy;						\
649 	do {								\
650 		__val_copy = copy;					\
651 		/*							\
652 		 * paired with u64_u32_store_copy(), ordering access	\
653 		 * to var and copy.					\
654 		 */							\
655 		smp_rmb();						\
656 		__val = var;						\
657 	} while (__val != __val_copy);					\
658 	__val;								\
659 })
660 # define u64_u32_store_copy(var, copy, val)				\
661 do {									\
662 	typeof(val) __val = (val);					\
663 	var = __val;							\
664 	/*								\
665 	 * paired with u64_u32_load_copy(), ordering access to var and	\
666 	 * copy.							\
667 	 */								\
668 	smp_wmb();							\
669 	copy = __val;							\
670 } while (0)
671 #endif
672 # define u64_u32_load(var)		u64_u32_load_copy(var, var##_copy)
673 # define u64_u32_store(var, val)	u64_u32_store_copy(var, var##_copy, val)
674 
675 struct balance_callback {
676 	struct balance_callback *next;
677 	void (*func)(struct rq *rq);
678 };
679 
680 /* Fair scheduling SCHED_{NORMAL,BATCH,IDLE} related fields in a runqueue: */
681 struct cfs_rq {
682 	struct load_weight	load;
683 	unsigned int		nr_queued;
684 	unsigned int		h_nr_queued;		/* SCHED_{NORMAL,BATCH,IDLE} */
685 	unsigned int		h_nr_runnable;		/* SCHED_{NORMAL,BATCH,IDLE} */
686 	unsigned int		h_nr_idle;		/* SCHED_IDLE */
687 
688 	s64			sum_w_vruntime;
689 	u64			sum_weight;
690 	u64			zero_vruntime;
691 	unsigned int		sum_shift;
692 
693 #ifdef CONFIG_SCHED_CORE
694 	unsigned int		forceidle_seq;
695 	u64			zero_vruntime_fi;
696 #endif
697 
698 	struct rb_root_cached	tasks_timeline;
699 
700 	/*
701 	 * 'curr' points to the currently running entity on this cfs_rq.
702 	 * It is set to NULL otherwise (i.e when none are currently running).
703 	 */
704 	struct sched_entity	*curr;
705 	struct sched_entity	*next;
706 
707 	/*
708 	 * CFS load tracking
709 	 */
710 	struct sched_entity	*h_curr;
711 	struct sched_avg	avg;
712 #ifndef CONFIG_64BIT
713 	u64			last_update_time_copy;
714 #endif
715 	struct {
716 		raw_spinlock_t	lock ____cacheline_aligned;
717 		int		nr;
718 		unsigned long	load_avg;
719 		unsigned long	util_avg;
720 		unsigned long	runnable_avg;
721 	} removed;
722 
723 #ifdef CONFIG_FAIR_GROUP_SCHED
724 	u64			last_update_tg_load_avg;
725 	unsigned long		tg_load_avg_contrib;
726 	unsigned long		tg_runnable_avg_contrib;
727 	long			propagate;
728 	long			prop_runnable_sum;
729 
730 	/*
731 	 *   h_load = weight * f(tg)
732 	 *
733 	 * Where f(tg) is the recursive weight fraction assigned to
734 	 * this group.
735 	 */
736 	unsigned long		h_load;
737 	u64			last_h_load_update;
738 	struct sched_entity	*h_load_next;
739 
740 	struct rq		*rq;	/* CPU runqueue to which this cfs_rq is attached */
741 
742 	/*
743 	 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
744 	 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
745 	 * (like users, containers etc.)
746 	 *
747 	 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
748 	 * This list is used during load balance.
749 	 */
750 	int			on_list;
751 	struct list_head	leaf_cfs_rq_list;
752 	struct task_group	*tg;	/* Group that "owns" this runqueue */
753 
754 	/* Locally cached copy of our task_group's idle value */
755 	int			idle;
756 
757 # ifdef CONFIG_CFS_BANDWIDTH
758 	int			runtime_enabled;
759 	s64			runtime_remaining;
760 
761 	u64			throttled_pelt_idle;
762 #  ifndef CONFIG_64BIT
763 	u64                     throttled_pelt_idle_copy;
764 #  endif
765 	u64			throttled_clock;
766 	u64			throttled_clock_pelt;
767 	u64			throttled_clock_pelt_time;
768 	u64			throttled_clock_self;
769 	u64			throttled_clock_self_time;
770 	bool			throttled:1;
771 	bool			pelt_clock_throttled:1;
772 	int			throttle_count;
773 	struct list_head	throttled_list;
774 	struct list_head	throttled_csd_list;
775 	struct list_head        throttled_limbo_list;
776 # endif /* CONFIG_CFS_BANDWIDTH */
777 #endif /* CONFIG_FAIR_GROUP_SCHED */
778 };
779 
780 #ifdef CONFIG_SCHED_CLASS_EXT
781 /* scx_rq->flags, protected by the rq lock */
782 enum scx_rq_flags {
783 	/*
784 	 * A hotplugged CPU starts scheduling before rq_online_scx(). Track
785 	 * ops.cpu_on/offline() state so that ops.enqueue/dispatch() are called
786 	 * only while the BPF scheduler considers the CPU to be online.
787 	 */
788 	SCX_RQ_ONLINE		= 1 << 0,
789 	SCX_RQ_CAN_STOP_TICK	= 1 << 1,
790 	SCX_RQ_CLK_VALID	= 1 << 5, /* RQ clock is fresh and valid */
791 	SCX_RQ_BAL_CB_PENDING	= 1 << 6, /* must queue a cb after dispatching */
792 	SCX_RQ_SUB_IDLE_RENOTIFY	= 1 << 7, /* sub-scheds are owed update_idle() */
793 	SCX_RQ_ROOT_IDLE_RENOTIFY	= 1 << 8, /* the root is owed update_idle() */
794 
795 	SCX_RQ_IN_WAKEUP	= 1 << 16,
796 	SCX_RQ_IN_DISPATCH	= 1 << 17,
797 };
798 
799 /* per-rq rescue execution state, see scx_rescue_timerfn() */
800 struct scx_rq_rescue {
801 	struct scx_dispatch_q	dsq;			/* stranded tasks awaiting rescue */
802 	s64			budget;			/* execution token bucket, ns */
803 	u64			clock;			/* last budget accrual timestamp */
804 	struct task_struct	*curr;			/* task being rescued, one at a time */
805 	s64			slice;			/* curr's admitted slice */
806 	u64			exec_snap;		/* sum_exec_runtime at admission */
807 	struct timer_list	timer;			/* paces admission and escalation */
808 	u64			kill_at;		/* last ejection, init before any */
809 };
810 
811 struct scx_rq {
812 	struct scx_dispatch_q	local_dsq;
813 #ifdef CONFIG_EXT_SUB_SCHED
814 	struct scx_dispatch_q	reject_dsq;		/* staging for cap-rejected tasks */
815 	struct scx_rq_rescue	rescue;
816 #endif
817 	struct list_head	runnable_list;		/* runnable tasks on this rq */
818 	struct list_head	ddsp_deferred_locals;	/* deferred ddsps from enq */
819 	unsigned long		ops_qseq;
820 	/* both stashed across the activate_task() in move_remote_task_to_local_dsq() */
821 	u64			remote_activate_enq_flags;
822 	struct scx_sched	*remote_activate_sch;
823 	u32			nr_running;
824 	u32			cpuperf_target;		/* [0, SCHED_CAPACITY_SCALE] */
825 	bool			in_select_cpu;
826 	bool			cpu_released;
827 	u32			flags;
828 	u32			nr_immed;		/* ENQ_IMMED tasks on local_dsq */
829 #ifdef CONFIG_SCHED_CORE
830 	u32			lock_drop_seq;	/* nr dispatch lock releases */
831 #endif
832 	u64			clock;			/* current per-rq clock -- see scx_bpf_now() */
833 #ifdef CONFIG_EXT_SUB_SCHED
834 	struct llist_head	ecaps_to_sync;		/* pending ecaps syncs */
835 	struct task_struct	*sub_dispatch_prev;
836 #endif
837 	cpumask_var_t		cpus_to_sync;
838 	bool			kick_sync_pending;
839 	unsigned long		kick_sync;
840 
841 	struct list_head	sched_pcpus_to_kick;	/* see kick_cpus_irq_workfn() */
842 
843 	raw_spinlock_t		deferred_reenq_lock;
844 	struct list_head	deferred_reenq_locals;	/* scheds requesting reenq of local DSQ */
845 	struct list_head	deferred_reenq_users;	/* user DSQs requesting reenq */
846 	struct balance_callback	deferred_bal_cb;
847 	struct balance_callback	kick_sync_bal_cb;
848 	struct irq_work		deferred_irq_work;
849 	struct irq_work		kick_cpus_irq_work;
850 };
851 #endif /* CONFIG_SCHED_CLASS_EXT */
852 
rt_bandwidth_enabled(void)853 static inline int rt_bandwidth_enabled(void)
854 {
855 	return sysctl_sched_rt_runtime >= 0;
856 }
857 
858 /* RT IPI pull logic requires IRQ_WORK */
859 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
860 # define HAVE_RT_PUSH_IPI
861 #endif
862 
863 /* Real-Time classes' related field in a runqueue: */
864 struct rt_rq {
865 	struct rt_prio_array	active;
866 	unsigned int		rt_nr_running;
867 	unsigned int		rr_nr_running;
868 	struct {
869 		int		curr; /* highest queued rt task prio */
870 		int		next; /* next highest */
871 	} highest_prio;
872 	bool			overloaded;
873 	struct plist_head	pushable_tasks;
874 
875 	int			rt_queued;
876 
877 #ifdef CONFIG_RT_GROUP_SCHED
878 	int			rt_throttled;
879 	u64			rt_time; /* consumed RT time, goes up in update_curr_rt */
880 	u64			rt_runtime; /* allotted RT time, "slice" from rt_bandwidth, RT sharing/balancing */
881 	/* Nests inside the rq lock: */
882 	raw_spinlock_t		rt_runtime_lock;
883 
884 	unsigned int		rt_nr_boosted;
885 
886 	struct rq		*rq; /* this is always top-level rq, cache? */
887 #endif
888 #ifdef CONFIG_CGROUP_SCHED
889 	struct task_group	*tg; /* this tg has "this" rt_rq on given CPU for runnable entities */
890 #endif
891 };
892 
rt_rq_is_runnable(struct rt_rq * rt_rq)893 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
894 {
895 	return rt_rq->rt_queued && rt_rq->rt_nr_running;
896 }
897 
898 /* Deadline class' related fields in a runqueue */
899 struct dl_rq {
900 	/* runqueue is an rbtree, ordered by deadline */
901 	struct rb_root_cached	root;
902 
903 	unsigned int		dl_nr_running;
904 
905 	/*
906 	 * Deadline values of the currently executing and the
907 	 * earliest ready task on this rq. Caching these facilitates
908 	 * the decision whether or not a ready but not running task
909 	 * should migrate somewhere else.
910 	 */
911 	struct {
912 		u64		curr;
913 		u64		next;
914 	} earliest_dl;
915 
916 	bool			overloaded;
917 
918 	struct sched_dl_entity	*curr;
919 	/*
920 	 * Tasks on this rq that can be pushed away. They are kept in
921 	 * an rb-tree, ordered by tasks' deadlines, with caching
922 	 * of the leftmost (earliest deadline) element.
923 	 */
924 	struct rb_root_cached	pushable_dl_tasks_root;
925 
926 	/*
927 	 * "Active utilization" for this runqueue: increased when a
928 	 * task wakes up (becomes TASK_RUNNING) and decreased when a
929 	 * task blocks
930 	 */
931 	u64			running_bw;
932 
933 	/*
934 	 * Utilization of the tasks "assigned" to this runqueue (including
935 	 * the tasks that are in runqueue and the tasks that executed on this
936 	 * CPU and blocked). Increased when a task moves to this runqueue, and
937 	 * decreased when the task moves away (migrates, changes scheduling
938 	 * policy, or terminates).
939 	 * This is needed to compute the "inactive utilization" for the
940 	 * runqueue (inactive utilization = this_bw - running_bw).
941 	 */
942 	u64			this_bw;
943 	u64			extra_bw;
944 
945 	/*
946 	 * Maximum available bandwidth for reclaiming by SCHED_FLAG_RECLAIM
947 	 * tasks of this rq. Used in calculation of reclaimable bandwidth(GRUB).
948 	 */
949 	u64			max_bw;
950 
951 	/*
952 	 * Inverse of the fraction of CPU utilization that can be reclaimed
953 	 * by the GRUB algorithm.
954 	 */
955 	u64			bw_ratio;
956 };
957 
958 #ifdef CONFIG_FAIR_GROUP_SCHED
959 /* Check whether a task group is root tg */
960 #define is_root_task_group(tg) ((tg) == &root_task_group)
961 /* An entity is a task if it doesn't "own" a runqueue */
962 #define entity_is_task(se)	(!se->my_q)
963 
se_update_runnable(struct sched_entity * se)964 static inline void se_update_runnable(struct sched_entity *se)
965 {
966 	if (!entity_is_task(se))
967 		se->runnable_weight = se->my_q->h_nr_runnable;
968 }
969 
se_runnable(struct sched_entity * se)970 static inline long se_runnable(struct sched_entity *se)
971 {
972 	if (se->sched_delayed)
973 		return false;
974 
975 	if (entity_is_task(se))
976 		return !!se->on_rq;
977 	else
978 		return se->runnable_weight;
979 }
980 
981 #else /* !CONFIG_FAIR_GROUP_SCHED: */
982 
983 #define entity_is_task(se)	1
984 
se_update_runnable(struct sched_entity * se)985 static inline void se_update_runnable(struct sched_entity *se) { }
986 
se_runnable(struct sched_entity * se)987 static inline long se_runnable(struct sched_entity *se)
988 {
989 	if (se->sched_delayed)
990 		return false;
991 
992 	return !!se->on_rq;
993 }
994 
995 #endif /* !CONFIG_FAIR_GROUP_SCHED */
996 
997 /*
998  * XXX we want to get rid of these helpers and use the full load resolution.
999  */
se_weight(struct sched_entity * se)1000 static inline long se_weight(struct sched_entity *se)
1001 {
1002 	return scale_load_down(se->load.weight);
1003 }
1004 
1005 
sched_asym_prefer(int a,int b)1006 static inline bool sched_asym_prefer(int a, int b)
1007 {
1008 	return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
1009 }
1010 
1011 struct perf_domain {
1012 	struct em_perf_domain *em_pd;
1013 	struct perf_domain *next;
1014 	struct rcu_head rcu;
1015 };
1016 
1017 /*
1018  * We add the notion of a root-domain which will be used to define per-domain
1019  * variables. Each exclusive cpuset essentially defines an island domain by
1020  * fully partitioning the member CPUs from any other cpuset. Whenever a new
1021  * exclusive cpuset is created, we also create and attach a new root-domain
1022  * object.
1023  *
1024  */
1025 struct root_domain {
1026 	atomic_t		refcount;
1027 	atomic_t		rto_count;
1028 	struct rcu_head		rcu;
1029 	cpumask_var_t		span;
1030 	cpumask_var_t		online;
1031 
1032 	/*
1033 	 * Indicate pullable load on at least one CPU, e.g:
1034 	 * - More than one runnable task
1035 	 * - Running task is misfit
1036 	 */
1037 	bool			overloaded;
1038 
1039 	/* Indicate one or more CPUs over-utilized (tipping point) */
1040 	bool			overutilized;
1041 
1042 	/*
1043 	 * The bit corresponding to a CPU gets set here if such CPU has more
1044 	 * than one runnable -deadline task (as it is below for RT tasks).
1045 	 */
1046 	cpumask_var_t		dlo_mask;
1047 	atomic_t		dlo_count;
1048 	struct dl_bw		dl_bw;
1049 	struct cpudl		cpudl;
1050 
1051 	/*
1052 	 * Indicate whether a root_domain's dl_bw has been checked or
1053 	 * updated. It's monotonously increasing value.
1054 	 *
1055 	 * Also, some corner cases, like 'wrap around' is dangerous, but given
1056 	 * that u64 is 'big enough'. So that shouldn't be a concern.
1057 	 */
1058 	u64 visit_cookie;
1059 
1060 #ifdef HAVE_RT_PUSH_IPI
1061 	/*
1062 	 * For IPI pull requests, loop across the rto_mask.
1063 	 */
1064 	struct irq_work		rto_push_work;
1065 	raw_spinlock_t		rto_lock;
1066 	/* These are only updated and read within rto_lock */
1067 	int			rto_loop;
1068 	int			rto_cpu;
1069 	/* These atomics are updated outside of a lock */
1070 	atomic_t		rto_loop_next;
1071 	atomic_t		rto_loop_start;
1072 #endif /* HAVE_RT_PUSH_IPI */
1073 	/*
1074 	 * The "RT overload" flag: it gets set if a CPU has more than
1075 	 * one runnable RT task.
1076 	 */
1077 	cpumask_var_t		rto_mask;
1078 	struct cpupri		cpupri;
1079 
1080 	/*
1081 	 * NULL-terminated list of performance domains intersecting with the
1082 	 * CPUs of the rd. Protected by RCU.
1083 	 */
1084 	struct perf_domain __rcu *pd;
1085 };
1086 
1087 extern void init_defrootdomain(void);
1088 extern int sched_init_domains(const struct cpumask *cpu_map);
1089 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
1090 extern void sched_get_rd(struct root_domain *rd);
1091 extern void sched_put_rd(struct root_domain *rd);
1092 
get_rd_overloaded(struct root_domain * rd)1093 static inline int get_rd_overloaded(struct root_domain *rd)
1094 {
1095 	return READ_ONCE(rd->overloaded);
1096 }
1097 
set_rd_overloaded(struct root_domain * rd,int status)1098 static inline void set_rd_overloaded(struct root_domain *rd, int status)
1099 {
1100 	if (get_rd_overloaded(rd) != status)
1101 		WRITE_ONCE(rd->overloaded, status);
1102 }
1103 
1104 #ifdef HAVE_RT_PUSH_IPI
1105 extern void rto_push_irq_work_func(struct irq_work *work);
1106 #endif
1107 
1108 #ifdef CONFIG_UCLAMP_TASK
1109 /*
1110  * struct uclamp_bucket - Utilization clamp bucket
1111  * @value: utilization clamp value for tasks on this clamp bucket
1112  * @tasks: number of RUNNABLE tasks on this clamp bucket
1113  *
1114  * Keep track of how many tasks are RUNNABLE for a given utilization
1115  * clamp value.
1116  */
1117 struct uclamp_bucket {
1118 	unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
1119 	unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
1120 };
1121 
1122 /*
1123  * struct uclamp_rq - rq's utilization clamp
1124  * @value: currently active clamp values for a rq
1125  * @bucket: utilization clamp buckets affecting a rq
1126  *
1127  * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
1128  * A clamp value is affecting a rq when there is at least one task RUNNABLE
1129  * (or actually running) with that value.
1130  *
1131  * There are up to UCLAMP_CNT possible different clamp values, currently there
1132  * are only two: minimum utilization and maximum utilization.
1133  *
1134  * All utilization clamping values are MAX aggregated, since:
1135  * - for util_min: we want to run the CPU at least at the max of the minimum
1136  *   utilization required by its currently RUNNABLE tasks.
1137  * - for util_max: we want to allow the CPU to run up to the max of the
1138  *   maximum utilization allowed by its currently RUNNABLE tasks.
1139  *
1140  * Since on each system we expect only a limited number of different
1141  * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
1142  * the metrics required to compute all the per-rq utilization clamp values.
1143  */
1144 struct uclamp_rq {
1145 	unsigned int value;
1146 	struct uclamp_bucket bucket[UCLAMP_BUCKETS];
1147 };
1148 
1149 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
1150 #endif /* CONFIG_UCLAMP_TASK */
1151 
1152 /*
1153  * This is the main, per-CPU runqueue data structure.
1154  *
1155  * Locking rule: those places that want to lock multiple runqueues
1156  * (such as the load balancing or the thread migration code), lock
1157  * acquire operations must be ordered by ascending &runqueue.
1158  */
1159 struct rq {
1160 	/*
1161 	 * The following members are loaded together, without holding the
1162 	 * rq->lock, in an extremely hot loop in update_sg_lb_stats()
1163 	 * (called from pick_next_task()). To reduce cache pollution from
1164 	 * this operation, they are placed together on this dedicated cache
1165 	 * line. Even though some of them are frequently modified, they are
1166 	 * loaded much more frequently than they are stored.
1167 	 */
1168 	unsigned int		nr_running;
1169 #ifdef CONFIG_NUMA_BALANCING
1170 	unsigned int		nr_numa_running;
1171 	unsigned int		nr_preferred_running;
1172 #endif
1173 	unsigned int		ttwu_pending;
1174 	unsigned long		cpu_capacity;
1175 #ifdef CONFIG_SCHED_PROXY_EXEC
1176 	struct task_struct __rcu	*donor;  /* Scheduling context */
1177 	struct task_struct __rcu	*curr;   /* Execution context */
1178 #else
1179 	union {
1180 		struct task_struct __rcu *donor; /* Scheduler context */
1181 		struct task_struct __rcu *curr;  /* Execution context */
1182 	};
1183 #endif
1184 	struct task_struct	*idle;
1185 	/* padding left here deliberately */
1186 
1187 	/*
1188 	 * The next cacheline holds the (hot) runqueue lock, as well as
1189 	 * some other less performance-critical fields.
1190 	 */
1191 	u64			nr_switches	____cacheline_aligned;
1192 
1193 	/* runqueue lock: */
1194 	raw_spinlock_t		__lock;
1195 
1196 #ifdef CONFIG_NO_HZ_COMMON
1197 	unsigned int		nohz_tick_stopped;
1198 	atomic_t		nohz_flags;
1199 	unsigned int		has_blocked_load;
1200 	unsigned long		last_blocked_load_update_tick;
1201 	call_single_data_t	nohz_csd;
1202 #endif /* CONFIG_NO_HZ_COMMON */
1203 
1204 #ifdef CONFIG_UCLAMP_TASK
1205 	/* Utilization clamp values based on CPU's RUNNABLE tasks */
1206 	struct uclamp_rq	uclamp[UCLAMP_CNT] ____cacheline_aligned;
1207 	unsigned int		uclamp_flags;
1208 #define UCLAMP_FLAG_IDLE 0x01
1209 #endif
1210 
1211 	struct cfs_rq		cfs;
1212 	struct rt_rq		rt;
1213 	struct dl_rq		dl;
1214 #ifdef CONFIG_SCHED_CLASS_EXT
1215 	struct scx_rq		scx;
1216 	struct sched_dl_entity	ext_server;
1217 #endif
1218 #ifdef CONFIG_SCHED_CACHE
1219 	raw_spinlock_t		cpu_epoch_lock ____cacheline_aligned;
1220 	u64			cpu_runtime;
1221 	unsigned long		cpu_epoch;
1222 	unsigned long		cpu_epoch_next;
1223 #endif
1224 
1225 	struct sched_dl_entity	fair_server;
1226 
1227 #ifdef CONFIG_FAIR_GROUP_SCHED
1228 	/* list of leaf cfs_rq on this CPU: */
1229 	struct list_head	leaf_cfs_rq_list;
1230 	struct list_head	*tmp_alone_branch;
1231 #endif /* CONFIG_FAIR_GROUP_SCHED */
1232 
1233 #ifdef CONFIG_NUMA_BALANCING
1234 	unsigned int		numa_migrate_on;
1235 #endif
1236 
1237 #ifdef CONFIG_SCHED_CACHE
1238 	unsigned int		nr_pref_llc_running;
1239 	unsigned int		nr_llc_running;
1240 #endif
1241 
1242 	/*
1243 	 * This is part of a global counter where only the total sum
1244 	 * over all CPUs matters. A task can increase this counter on
1245 	 * one CPU and if it got migrated afterwards it may decrease
1246 	 * it on another CPU. Always updated under the runqueue lock:
1247 	 */
1248 	unsigned long		nr_uninterruptible;
1249 
1250 	struct sched_dl_entity	*dl_server;
1251 	struct task_struct	*stop;
1252 	const struct sched_class *next_class;
1253 	unsigned long		next_balance;
1254 	struct mm_struct	*prev_mm;
1255 
1256 	/*
1257 	 * The following fields of clock data are frequently referenced
1258 	 * and updated together, and should go on their own cache line.
1259 	 */
1260 	u64			clock_task ____cacheline_aligned;
1261 	u64			clock_pelt;
1262 	u64			clock;
1263 	unsigned long		lost_idle_time;
1264 	unsigned int		clock_update_flags;
1265 	u64			clock_pelt_idle;
1266 	u64			clock_idle;
1267 
1268 #ifndef CONFIG_64BIT
1269 	u64			clock_pelt_idle_copy;
1270 	u64			clock_idle_copy;
1271 #endif
1272 
1273 	u64 last_seen_need_resched_ns;
1274 	int ticks_without_resched;
1275 
1276 #ifdef CONFIG_MEMBARRIER
1277 	int membarrier_state;
1278 #endif
1279 
1280 	struct root_domain		*rd;
1281 	struct sched_domain __rcu	*sd;
1282 
1283 	struct balance_callback *balance_callback;
1284 
1285 	unsigned char		nohz_idle_balance;
1286 	unsigned char		idle_balance;
1287 
1288 	unsigned long		misfit_task_load;
1289 
1290 	/* For active balancing */
1291 	int			active_balance;
1292 	int			push_cpu;
1293 	struct cpu_stop_work	active_balance_work;
1294 
1295 	/* CPU of this runqueue: */
1296 	int			cpu;
1297 	int			online;
1298 
1299 	struct list_head cfs_tasks;
1300 
1301 	struct sched_avg	avg_rt;
1302 	struct sched_avg	avg_dl;
1303 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1304 	struct sched_avg	avg_irq;
1305 #endif
1306 #ifdef CONFIG_SCHED_HW_PRESSURE
1307 	struct sched_avg	avg_hw;
1308 #endif
1309 	u64			idle_stamp;
1310 	u64			avg_idle;
1311 
1312 	/* This is used to determine avg_idle's max value */
1313 	u64			max_idle_balance_cost;
1314 
1315 #ifdef CONFIG_HOTPLUG_CPU
1316 	struct rcuwait		hotplug_wait;
1317 #endif
1318 
1319 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1320 	u64			prev_irq_time;
1321 	u64			psi_irq_time;
1322 #endif
1323 #ifdef CONFIG_PARAVIRT
1324 	u64			prev_steal_time;
1325 #endif
1326 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1327 	u64			prev_steal_time_rq;
1328 #endif
1329 
1330 	/* calc_load related fields */
1331 	unsigned long		calc_load_update;
1332 	long			calc_load_active;
1333 
1334 #ifdef CONFIG_SCHED_HRTICK
1335 	call_single_data_t	hrtick_csd;
1336 	struct hrtimer		hrtick_timer;
1337 	ktime_t			hrtick_time;
1338 	ktime_t			hrtick_delay;
1339 	unsigned int		hrtick_sched;
1340 #endif
1341 
1342 #ifdef CONFIG_SCHEDSTATS
1343 	/* latency stats */
1344 	struct sched_info	rq_sched_info;
1345 	unsigned long long	rq_cpu_time;
1346 
1347 	/* sys_sched_yield() stats */
1348 	unsigned int		yld_count;
1349 
1350 	/* schedule() stats */
1351 	unsigned int		sched_count;
1352 	unsigned int		sched_goidle;
1353 
1354 	/* try_to_wake_up() stats */
1355 	unsigned int		ttwu_count;
1356 	unsigned int		ttwu_local;
1357 #endif
1358 
1359 #ifdef CONFIG_CPU_IDLE
1360 	/* Must be inspected within a RCU lock section */
1361 	struct cpuidle_state	*idle_state;
1362 #endif
1363 
1364 	unsigned int		nr_pinned;
1365 	unsigned int		push_busy;
1366 	struct cpu_stop_work	push_work;
1367 
1368 #ifdef CONFIG_SCHED_CORE
1369 	/* per rq */
1370 	struct rq		*core;
1371 	struct task_struct	*core_pick;
1372 	struct sched_dl_entity	*core_dl_server;
1373 	unsigned int		core_enabled;
1374 	unsigned int		core_sched_seq;
1375 	struct rb_root		core_tree;
1376 
1377 	/* shared state -- careful with sched_core_cpu_deactivate() */
1378 	unsigned int		core_task_seq;
1379 	unsigned int		core_pick_seq;
1380 	unsigned long		core_cookie;
1381 	unsigned int		core_forceidle_count;
1382 	unsigned int		core_forceidle_seq;
1383 	unsigned int		core_forceidle_occupation;
1384 	u64			core_forceidle_start;
1385 	unsigned int		core_pick_in_flight;
1386 #endif /* CONFIG_SCHED_CORE */
1387 
1388 	/* Scratch cpumask to be temporarily used under rq_lock */
1389 	cpumask_var_t		scratch_mask;
1390 
1391 #ifdef CONFIG_CFS_BANDWIDTH
1392 	call_single_data_t	cfsb_csd;
1393 	struct list_head	cfsb_csd_list;
1394 #endif
1395 
1396 	atomic_t		nr_iowait;
1397 } __no_randomize_layout;
1398 
1399 #ifdef CONFIG_FAIR_GROUP_SCHED
1400 
1401 /* CPU runqueue to which this cfs_rq is attached */
rq_of(struct cfs_rq * cfs_rq)1402 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1403 {
1404 	return cfs_rq->rq;
1405 }
1406 
1407 #else /* !CONFIG_FAIR_GROUP_SCHED: */
1408 
rq_of(struct cfs_rq * cfs_rq)1409 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1410 {
1411 	return container_of(cfs_rq, struct rq, cfs);
1412 }
1413 #endif /* !CONFIG_FAIR_GROUP_SCHED */
1414 
cpu_of(struct rq * rq)1415 static inline int cpu_of(struct rq *rq)
1416 {
1417 	return rq->cpu;
1418 }
1419 
1420 #define MDF_PUSH		0x01
1421 
is_migration_disabled(struct task_struct * p)1422 static inline bool is_migration_disabled(struct task_struct *p)
1423 {
1424 	return p->migration_disabled;
1425 }
1426 
1427 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1428 DECLARE_PER_CPU(struct rnd_state, sched_rnd_state);
1429 
sched_rng(void)1430 static inline u32 sched_rng(void)
1431 {
1432 	return prandom_u32_state(this_cpu_ptr(&sched_rnd_state));
1433 }
1434 
__this_rq(void)1435 static __always_inline struct rq *__this_rq(void)
1436 {
1437 	return this_cpu_ptr(&runqueues);
1438 }
1439 
1440 #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
1441 #define this_rq()		__this_rq()
1442 #define task_rq(p)		cpu_rq(task_cpu(p))
1443 #define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
1444 #define raw_rq()		raw_cpu_ptr(&runqueues)
1445 
idle_rq(struct rq * rq)1446 static inline bool idle_rq(struct rq *rq)
1447 {
1448 	return rq->curr == rq->idle && !rq->nr_running && !rq->ttwu_pending;
1449 }
1450 
1451 /**
1452  * available_idle_cpu - is a given CPU idle for enqueuing work.
1453  * @cpu: the CPU in question.
1454  *
1455  * Return: 1 if the CPU is currently idle. 0 otherwise.
1456  */
available_idle_cpu(int cpu)1457 static inline bool available_idle_cpu(int cpu)
1458 {
1459 	if (!idle_rq(cpu_rq(cpu)))
1460 		return 0;
1461 
1462 	if (vcpu_is_preempted(cpu))
1463 		return 0;
1464 
1465 	return 1;
1466 }
1467 
1468 #ifdef CONFIG_SCHED_PROXY_EXEC
rq_set_donor(struct rq * rq,struct task_struct * t)1469 static inline void rq_set_donor(struct rq *rq, struct task_struct *t)
1470 {
1471 	rcu_assign_pointer(rq->donor, t);
1472 }
1473 #else
rq_set_donor(struct rq * rq,struct task_struct * t)1474 static inline void rq_set_donor(struct rq *rq, struct task_struct *t)
1475 {
1476 	/* Do nothing */
1477 }
1478 #endif
1479 
1480 #ifdef CONFIG_SCHED_CORE
1481 static inline struct cpumask *sched_group_span(struct sched_group *sg);
1482 
1483 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled);
1484 
sched_core_enabled(struct rq * rq)1485 static inline bool sched_core_enabled(struct rq *rq)
1486 {
1487 	return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled;
1488 }
1489 
sched_core_disabled(void)1490 static inline bool sched_core_disabled(void)
1491 {
1492 	return !static_branch_unlikely(&__sched_core_enabled);
1493 }
1494 
1495 /*
1496  * Be careful with this function; not for general use. The return value isn't
1497  * stable unless you actually hold a relevant rq->__lock.
1498  */
rq_lockp(struct rq * rq)1499 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1500 {
1501 	if (sched_core_enabled(rq))
1502 		return &rq->core->__lock;
1503 
1504 	return &rq->__lock;
1505 }
1506 
__rq_lockp(struct rq * rq)1507 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1508 	__returns_ctx_lock(rq_lockp(rq)) /* alias them */
1509 {
1510 	if (rq->core_enabled)
1511 		return &rq->core->__lock;
1512 
1513 	return &rq->__lock;
1514 }
1515 
1516 extern bool
1517 cfs_prio_less(const struct task_struct *a, const struct task_struct *b, bool fi);
1518 
1519 extern void task_vruntime_update(struct rq *rq, struct task_struct *p, bool in_fi);
1520 
1521 /*
1522  * Helpers to check if the CPU's core cookie matches with the task's cookie
1523  * when core scheduling is enabled.
1524  * A special case is that the task's cookie always matches with CPU's core
1525  * cookie if the CPU is in an idle core.
1526  */
sched_cpu_cookie_match(struct rq * rq,struct task_struct * p)1527 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1528 {
1529 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1530 	if (!sched_core_enabled(rq))
1531 		return true;
1532 
1533 	return rq->core->core_cookie == p->core_cookie;
1534 }
1535 
sched_core_cookie_match(struct rq * rq,struct task_struct * p)1536 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1537 {
1538 	bool idle_core = true;
1539 	int cpu;
1540 
1541 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1542 	if (!sched_core_enabled(rq))
1543 		return true;
1544 
1545 	if (rq->core->core_cookie == p->core_cookie)
1546 		return true;
1547 
1548 	for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) {
1549 		if (!available_idle_cpu(cpu)) {
1550 			idle_core = false;
1551 			break;
1552 		}
1553 	}
1554 
1555 	/*
1556 	 * A CPU in an idle core is always the best choice for tasks with
1557 	 * cookies.
1558 	 */
1559 	return idle_core;
1560 }
1561 
sched_group_cookie_match(struct rq * rq,struct task_struct * p,struct sched_group * group)1562 static inline bool sched_group_cookie_match(struct rq *rq,
1563 					    struct task_struct *p,
1564 					    struct sched_group *group)
1565 {
1566 	int cpu;
1567 
1568 	/* Ignore cookie match if core scheduler is not enabled on the CPU. */
1569 	if (!sched_core_enabled(rq))
1570 		return true;
1571 
1572 	for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
1573 		if (sched_core_cookie_match(cpu_rq(cpu), p))
1574 			return true;
1575 	}
1576 	return false;
1577 }
1578 
sched_core_enqueued(struct task_struct * p)1579 static inline bool sched_core_enqueued(struct task_struct *p)
1580 {
1581 	return !RB_EMPTY_NODE(&p->core_node);
1582 }
1583 
1584 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p);
1585 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags);
1586 
1587 extern void sched_core_get(void);
1588 extern void sched_core_put(void);
1589 
task_has_sched_core(struct task_struct * p)1590 static inline bool task_has_sched_core(struct task_struct *p)
1591 {
1592 	if (sched_core_disabled())
1593 		return false;
1594 
1595 	return !!p->core_cookie;
1596 }
1597 
1598 #else /* !CONFIG_SCHED_CORE: */
1599 
sched_core_enabled(struct rq * rq)1600 static inline bool sched_core_enabled(struct rq *rq)
1601 {
1602 	return false;
1603 }
1604 
sched_core_disabled(void)1605 static inline bool sched_core_disabled(void)
1606 {
1607 	return true;
1608 }
1609 
rq_lockp(struct rq * rq)1610 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1611 {
1612 	return &rq->__lock;
1613 }
1614 
__rq_lockp(struct rq * rq)1615 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1616 	__returns_ctx_lock(rq_lockp(rq)) /* alias them */
1617 {
1618 	return &rq->__lock;
1619 }
1620 
sched_cpu_cookie_match(struct rq * rq,struct task_struct * p)1621 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1622 {
1623 	return true;
1624 }
1625 
sched_core_cookie_match(struct rq * rq,struct task_struct * p)1626 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1627 {
1628 	return true;
1629 }
1630 
sched_group_cookie_match(struct rq * rq,struct task_struct * p,struct sched_group * group)1631 static inline bool sched_group_cookie_match(struct rq *rq,
1632 					    struct task_struct *p,
1633 					    struct sched_group *group)
1634 {
1635 	return true;
1636 }
1637 
task_has_sched_core(struct task_struct * p)1638 static inline bool task_has_sched_core(struct task_struct *p)
1639 {
1640 	return false;
1641 }
1642 
1643 #endif /* !CONFIG_SCHED_CORE */
1644 
1645 #ifdef CONFIG_RT_GROUP_SCHED
1646 # ifdef CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED
1647 DECLARE_STATIC_KEY_FALSE(rt_group_sched);
rt_group_sched_enabled(void)1648 static inline bool rt_group_sched_enabled(void)
1649 {
1650 	return static_branch_unlikely(&rt_group_sched);
1651 }
1652 # else /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED: */
1653 DECLARE_STATIC_KEY_TRUE(rt_group_sched);
rt_group_sched_enabled(void)1654 static inline bool rt_group_sched_enabled(void)
1655 {
1656 	return static_branch_likely(&rt_group_sched);
1657 }
1658 # endif /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED */
1659 #else /* !CONFIG_RT_GROUP_SCHED: */
1660 # define rt_group_sched_enabled()	false
1661 #endif /* !CONFIG_RT_GROUP_SCHED */
1662 
lockdep_assert_rq_held(struct rq * rq)1663 static inline void lockdep_assert_rq_held(struct rq *rq)
1664 	__assumes_ctx_lock(__rq_lockp(rq))
1665 {
1666 	lockdep_assert_held(__rq_lockp(rq));
1667 }
1668 
1669 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass)
1670 	__acquires(__rq_lockp(rq));
1671 
1672 extern bool raw_spin_rq_trylock(struct rq *rq)
1673 	__cond_acquires(true, __rq_lockp(rq));
1674 
raw_spin_rq_lock(struct rq * rq)1675 static inline void raw_spin_rq_lock(struct rq *rq)
1676 	__acquires(__rq_lockp(rq))
1677 {
1678 	raw_spin_rq_lock_nested(rq, 0);
1679 }
1680 
raw_spin_rq_unlock(struct rq * rq)1681 static inline void raw_spin_rq_unlock(struct rq *rq)
1682 	__releases(__rq_lockp(rq))
1683 {
1684 	raw_spin_unlock(rq_lockp(rq));
1685 }
1686 
raw_spin_rq_lock_irq(struct rq * rq)1687 static inline void raw_spin_rq_lock_irq(struct rq *rq)
1688 	__acquires(__rq_lockp(rq))
1689 {
1690 	local_irq_disable();
1691 	raw_spin_rq_lock(rq);
1692 }
1693 
raw_spin_rq_unlock_irq(struct rq * rq)1694 static inline void raw_spin_rq_unlock_irq(struct rq *rq)
1695 	__releases(__rq_lockp(rq))
1696 {
1697 	raw_spin_rq_unlock(rq);
1698 	local_irq_enable();
1699 }
1700 
_raw_spin_rq_lock_irqsave(struct rq * rq)1701 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq)
1702 	__acquires(__rq_lockp(rq))
1703 {
1704 	unsigned long flags;
1705 
1706 	local_irq_save(flags);
1707 	raw_spin_rq_lock(rq);
1708 
1709 	return flags;
1710 }
1711 
raw_spin_rq_unlock_irqrestore(struct rq * rq,unsigned long flags)1712 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags)
1713 	__releases(__rq_lockp(rq))
1714 {
1715 	raw_spin_rq_unlock(rq);
1716 	local_irq_restore(flags);
1717 }
1718 
1719 #define raw_spin_rq_lock_irqsave(rq, flags)	\
1720 do {						\
1721 	flags = _raw_spin_rq_lock_irqsave(rq);	\
1722 } while (0)
1723 
1724 extern void __update_idle_core(struct rq *rq);
1725 
update_idle_core(struct rq * rq)1726 static inline void update_idle_core(struct rq *rq)
1727 {
1728 	if (sched_smt_active())
1729 		__update_idle_core(rq);
1730 }
1731 
1732 #ifdef CONFIG_FAIR_GROUP_SCHED
task_of(struct sched_entity * se)1733 static inline struct task_struct *task_of(struct sched_entity *se)
1734 {
1735 	WARN_ON_ONCE(!entity_is_task(se));
1736 	return container_of(se, struct task_struct, se);
1737 }
1738 
task_cfs_rq(struct task_struct * p)1739 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1740 {
1741 	return p->se.cfs_rq;
1742 }
1743 
1744 /* runqueue on which this entity is (to be) queued */
cfs_rq_of(const struct sched_entity * se)1745 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1746 {
1747 	return se->cfs_rq;
1748 }
1749 
1750 /* runqueue "owned" by this group */
group_cfs_rq(struct sched_entity * grp)1751 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1752 {
1753 	return grp->my_q;
1754 }
1755 
1756 #else /* !CONFIG_FAIR_GROUP_SCHED: */
1757 
1758 #define task_of(_se)		container_of(_se, struct task_struct, se)
1759 
task_cfs_rq(const struct task_struct * p)1760 static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p)
1761 {
1762 	return &task_rq(p)->cfs;
1763 }
1764 
cfs_rq_of(const struct sched_entity * se)1765 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1766 {
1767 	const struct task_struct *p = task_of(se);
1768 	struct rq *rq = task_rq(p);
1769 
1770 	return &rq->cfs;
1771 }
1772 
1773 /* runqueue "owned" by this group */
group_cfs_rq(struct sched_entity * grp)1774 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1775 {
1776 	return NULL;
1777 }
1778 
1779 #endif /* !CONFIG_FAIR_GROUP_SCHED */
1780 
1781 extern void update_rq_avg_idle(struct rq *rq);
1782 extern void update_rq_clock(struct rq *rq);
1783 
1784 /*
1785  * rq::clock_update_flags bits
1786  *
1787  * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1788  *  call to __schedule(). This is an optimisation to avoid
1789  *  neighbouring rq clock updates.
1790  *
1791  * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1792  *  in effect and calls to update_rq_clock() are being ignored.
1793  *
1794  * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1795  *  made to update_rq_clock() since the last time rq::lock was pinned.
1796  *
1797  * If inside of __schedule(), clock_update_flags will have been
1798  * shifted left (a left shift is a cheap operation for the fast path
1799  * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1800  *
1801  *	if (rq-clock_update_flags >= RQCF_UPDATED)
1802  *
1803  * to check if %RQCF_UPDATED is set. It'll never be shifted more than
1804  * one position though, because the next rq_unpin_lock() will shift it
1805  * back.
1806  */
1807 #define RQCF_REQ_SKIP		0x01
1808 #define RQCF_ACT_SKIP		0x02
1809 #define RQCF_UPDATED		0x04
1810 
assert_clock_updated(struct rq * rq)1811 static inline void assert_clock_updated(struct rq *rq)
1812 {
1813 	/*
1814 	 * The only reason for not seeing a clock update since the
1815 	 * last rq_pin_lock() is if we're currently skipping updates.
1816 	 */
1817 	WARN_ON_ONCE(rq->clock_update_flags < RQCF_ACT_SKIP);
1818 }
1819 
rq_clock(struct rq * rq)1820 static inline u64 rq_clock(struct rq *rq)
1821 {
1822 	lockdep_assert_rq_held(rq);
1823 	assert_clock_updated(rq);
1824 
1825 	return rq->clock;
1826 }
1827 
rq_clock_task(struct rq * rq)1828 static inline u64 rq_clock_task(struct rq *rq)
1829 {
1830 	lockdep_assert_rq_held(rq);
1831 	assert_clock_updated(rq);
1832 
1833 	return rq->clock_task;
1834 }
1835 
rq_clock_skip_update(struct rq * rq)1836 static inline void rq_clock_skip_update(struct rq *rq)
1837 {
1838 	lockdep_assert_rq_held(rq);
1839 	rq->clock_update_flags |= RQCF_REQ_SKIP;
1840 }
1841 
1842 /*
1843  * See rt task throttling, which is the only time a skip
1844  * request is canceled.
1845  */
rq_clock_cancel_skipupdate(struct rq * rq)1846 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1847 {
1848 	lockdep_assert_rq_held(rq);
1849 	rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1850 }
1851 
1852 /*
1853  * During cpu offlining and rq wide unthrottling, we can trigger
1854  * an update_rq_clock() for several cfs and rt runqueues (Typically
1855  * when using list_for_each_entry_*)
1856  * rq_clock_start_loop_update() can be called after updating the clock
1857  * once and before iterating over the list to prevent multiple update.
1858  * After the iterative traversal, we need to call rq_clock_stop_loop_update()
1859  * to clear RQCF_ACT_SKIP of rq->clock_update_flags.
1860  */
rq_clock_start_loop_update(struct rq * rq)1861 static inline void rq_clock_start_loop_update(struct rq *rq)
1862 {
1863 	lockdep_assert_rq_held(rq);
1864 	WARN_ON_ONCE(rq->clock_update_flags & RQCF_ACT_SKIP);
1865 	rq->clock_update_flags |= RQCF_ACT_SKIP;
1866 }
1867 
rq_clock_stop_loop_update(struct rq * rq)1868 static inline void rq_clock_stop_loop_update(struct rq *rq)
1869 {
1870 	lockdep_assert_rq_held(rq);
1871 	rq->clock_update_flags &= ~RQCF_ACT_SKIP;
1872 }
1873 
1874 struct rq_flags {
1875 	unsigned long flags;
1876 	struct pin_cookie cookie;
1877 	/*
1878 	 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1879 	 * current pin context is stashed here in case it needs to be
1880 	 * restored in rq_repin_lock().
1881 	 */
1882 	unsigned int clock_update_flags;
1883 };
1884 
1885 extern struct balance_callback balance_push_callback;
1886 
1887 #ifdef CONFIG_SCHED_CLASS_EXT
1888 extern const struct sched_class ext_sched_class;
1889 
1890 DECLARE_STATIC_KEY_FALSE(__scx_enabled);	/* SCX BPF scheduler loaded */
1891 DECLARE_STATIC_KEY_FALSE(__scx_switched_all);	/* all fair class tasks on SCX */
1892 
1893 #define scx_enabled()		static_branch_unlikely(&__scx_enabled)
1894 #define scx_switched_all()	static_branch_unlikely(&__scx_switched_all)
1895 
scx_rq_clock_update(struct rq * rq,u64 clock)1896 static inline void scx_rq_clock_update(struct rq *rq, u64 clock)
1897 {
1898 	if (!scx_enabled())
1899 		return;
1900 	WRITE_ONCE(rq->scx.clock, clock);
1901 	smp_store_release(&rq->scx.flags, rq->scx.flags | SCX_RQ_CLK_VALID);
1902 }
1903 
scx_rq_clock_invalidate(struct rq * rq)1904 static inline void scx_rq_clock_invalidate(struct rq *rq)
1905 {
1906 	if (!scx_enabled())
1907 		return;
1908 	WRITE_ONCE(rq->scx.flags, rq->scx.flags & ~SCX_RQ_CLK_VALID);
1909 }
1910 
1911 #else /* !CONFIG_SCHED_CLASS_EXT: */
1912 #define scx_enabled()		false
1913 #define scx_switched_all()	false
1914 
scx_rq_clock_update(struct rq * rq,u64 clock)1915 static inline void scx_rq_clock_update(struct rq *rq, u64 clock) {}
scx_rq_clock_invalidate(struct rq * rq)1916 static inline void scx_rq_clock_invalidate(struct rq *rq) {}
1917 #endif /* !CONFIG_SCHED_CLASS_EXT */
1918 
assert_balance_callbacks_empty(struct rq * rq)1919 static inline void assert_balance_callbacks_empty(struct rq *rq)
1920 {
1921 	WARN_ON_ONCE(IS_ENABLED(CONFIG_PROVE_LOCKING) &&
1922 		     rq->balance_callback &&
1923 		     rq->balance_callback != &balance_push_callback);
1924 }
1925 
1926 /*
1927  * Lockdep annotation that avoids accidental unlocks; it's like a
1928  * sticky/continuous lockdep_assert_held().
1929  *
1930  * This avoids code that has access to 'struct rq *rq' (basically everything in
1931  * the scheduler) from accidentally unlocking the rq if they do not also have a
1932  * copy of the (on-stack) 'struct rq_flags rf'.
1933  *
1934  * Also see Documentation/locking/lockdep-design.rst.
1935  */
rq_pin_lock(struct rq * rq,struct rq_flags * rf)1936 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1937 {
1938 	rf->cookie = lockdep_pin_lock(__rq_lockp(rq));
1939 
1940 	rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1941 	rf->clock_update_flags = 0;
1942 	assert_balance_callbacks_empty(rq);
1943 }
1944 
rq_unpin_lock(struct rq * rq,struct rq_flags * rf)1945 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1946 {
1947 	if (rq->clock_update_flags > RQCF_ACT_SKIP)
1948 		rf->clock_update_flags = RQCF_UPDATED;
1949 
1950 	scx_rq_clock_invalidate(rq);
1951 	lockdep_unpin_lock(__rq_lockp(rq), rf->cookie);
1952 }
1953 
rq_repin_lock(struct rq * rq,struct rq_flags * rf)1954 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1955 {
1956 	lockdep_repin_lock(__rq_lockp(rq), rf->cookie);
1957 
1958 	/*
1959 	 * Restore the value we stashed in @rf for this pin context.
1960 	 */
1961 	rq->clock_update_flags |= rf->clock_update_flags;
1962 }
1963 
1964 #define __task_rq_lock(...) __acquire_ret(___task_rq_lock(__VA_ARGS__), __rq_lockp(__ret))
1965 extern struct rq *___task_rq_lock(struct task_struct *p, struct rq_flags *rf) __acquires_ret;
1966 
1967 #define task_rq_lock(...) __acquire_ret(_task_rq_lock(__VA_ARGS__), __rq_lockp(__ret))
1968 extern struct rq *_task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1969 	__acquires(&p->pi_lock) __acquires_ret;
1970 
1971 static inline void
__task_rq_unlock(struct rq * rq,struct task_struct * p,struct rq_flags * rf)1972 __task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1973 	__releases(__rq_lockp(rq))
1974 {
1975 	rq_unpin_lock(rq, rf);
1976 	raw_spin_rq_unlock(rq);
1977 }
1978 
1979 static inline void
task_rq_unlock(struct rq * rq,struct task_struct * p,struct rq_flags * rf)1980 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1981 	__releases(__rq_lockp(rq), &p->pi_lock)
1982 {
1983 	__task_rq_unlock(rq, p, rf);
1984 	raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1985 }
1986 
1987 DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct,
1988 		    _T->rq = task_rq_lock(_T->lock, &_T->rf),
1989 		    task_rq_unlock(_T->rq, _T->lock, &_T->rf),
1990 		    struct rq *rq; struct rq_flags rf)
1991 DECLARE_LOCK_GUARD_1_ATTRS(task_rq_lock, __acquires(_T->pi_lock), __releases((*(struct task_struct **)_T)->pi_lock))
1992 #define class_task_rq_lock_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(task_rq_lock, _T)
1993 
1994 DEFINE_LOCK_GUARD_1(__task_rq_lock, struct task_struct,
1995 		    _T->rq = __task_rq_lock(_T->lock, &_T->rf),
1996 		    __task_rq_unlock(_T->rq, _T->lock, &_T->rf),
1997 		    struct rq *rq; struct rq_flags rf)
1998 
rq_lock_irqsave(struct rq * rq,struct rq_flags * rf)1999 static inline void rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
2000 	__acquires(__rq_lockp(rq))
2001 {
2002 	raw_spin_rq_lock_irqsave(rq, rf->flags);
2003 	rq_pin_lock(rq, rf);
2004 }
2005 
rq_lock_irq(struct rq * rq,struct rq_flags * rf)2006 static inline void rq_lock_irq(struct rq *rq, struct rq_flags *rf)
2007 	__acquires(__rq_lockp(rq))
2008 {
2009 	raw_spin_rq_lock_irq(rq);
2010 	rq_pin_lock(rq, rf);
2011 }
2012 
rq_lock(struct rq * rq,struct rq_flags * rf)2013 static inline void rq_lock(struct rq *rq, struct rq_flags *rf)
2014 	__acquires(__rq_lockp(rq))
2015 {
2016 	raw_spin_rq_lock(rq);
2017 	rq_pin_lock(rq, rf);
2018 }
2019 
rq_unlock_irqrestore(struct rq * rq,struct rq_flags * rf)2020 static inline void rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
2021 	__releases(__rq_lockp(rq))
2022 {
2023 	rq_unpin_lock(rq, rf);
2024 	raw_spin_rq_unlock_irqrestore(rq, rf->flags);
2025 }
2026 
rq_unlock_irq(struct rq * rq,struct rq_flags * rf)2027 static inline void rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
2028 	__releases(__rq_lockp(rq))
2029 {
2030 	rq_unpin_lock(rq, rf);
2031 	raw_spin_rq_unlock_irq(rq);
2032 }
2033 
rq_unlock(struct rq * rq,struct rq_flags * rf)2034 static inline void rq_unlock(struct rq *rq, struct rq_flags *rf)
2035 	__releases(__rq_lockp(rq))
2036 {
2037 	rq_unpin_lock(rq, rf);
2038 	raw_spin_rq_unlock(rq);
2039 }
2040 
2041 DEFINE_LOCK_GUARD_1(rq_lock, struct rq,
2042 		    rq_lock(_T->lock, &_T->rf),
2043 		    rq_unlock(_T->lock, &_T->rf),
2044 		    struct rq_flags rf)
2045 
2046 DECLARE_LOCK_GUARD_1_ATTRS(rq_lock, __acquires(__rq_lockp(_T)),
2047 			   __releases(__rq_lockp(*(struct rq **)_T)));
2048 #define class_rq_lock_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock, _T)
2049 
2050 DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq,
2051 		    rq_lock_irq(_T->lock, &_T->rf),
2052 		    rq_unlock_irq(_T->lock, &_T->rf),
2053 		    struct rq_flags rf)
2054 
2055 DECLARE_LOCK_GUARD_1_ATTRS(rq_lock_irq, __acquires(__rq_lockp(_T)),
2056 			   __releases(__rq_lockp(*(struct rq **)_T)));
2057 #define class_rq_lock_irq_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock_irq, _T)
2058 
2059 DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq,
2060 		    rq_lock_irqsave(_T->lock, &_T->rf),
2061 		    rq_unlock_irqrestore(_T->lock, &_T->rf),
2062 		    struct rq_flags rf)
2063 
2064 DECLARE_LOCK_GUARD_1_ATTRS(rq_lock_irqsave, __acquires(__rq_lockp(_T)),
2065 			   __releases(__rq_lockp(*(struct rq **)_T)));
2066 #define class_rq_lock_irqsave_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock_irqsave, _T)
2067 
2068 DEFINE_LOCK_GUARD_1(raw_spin_rq_lock_irqsave, struct rq,
2069 		    raw_spin_rq_lock_irqsave(_T->lock, _T->flags),
2070 		    raw_spin_rq_unlock_irqrestore(_T->lock, _T->flags),
2071 		    unsigned long flags)
2072 
2073 DECLARE_LOCK_GUARD_1_ATTRS(raw_spin_rq_lock_irqsave, __acquires(__rq_lockp(_T)),
2074 			   __releases(__rq_lockp(*(struct rq **)_T)));
2075 #define class_raw_spin_rq_lock_irqsave_constructor(_T) \
2076 	WITH_LOCK_GUARD_1_ATTRS(raw_spin_rq_lock_irqsave, _T)
2077 
2078 #define this_rq_lock_irq(...) __acquire_ret(_this_rq_lock_irq(__VA_ARGS__), __rq_lockp(__ret))
_this_rq_lock_irq(struct rq_flags * rf)2079 static inline struct rq *_this_rq_lock_irq(struct rq_flags *rf) __acquires_ret
2080 {
2081 	struct rq *rq;
2082 
2083 	local_irq_disable();
2084 	rq = this_rq();
2085 	rq_lock(rq, rf);
2086 
2087 	return rq;
2088 }
2089 
2090 #ifdef CONFIG_NUMA
2091 
2092 enum numa_topology_type {
2093 	NUMA_DIRECT,
2094 	NUMA_GLUELESS_MESH,
2095 	NUMA_BACKPLANE,
2096 };
2097 
2098 extern enum numa_topology_type sched_numa_topology_type;
2099 extern int sched_max_numa_distance;
2100 extern bool find_numa_distance(int distance);
2101 extern void sched_init_numa(int offline_node);
2102 extern void sched_update_numa(int cpu, bool online);
2103 extern void sched_domains_numa_masks_set(unsigned int cpu);
2104 extern void sched_domains_numa_masks_clear(unsigned int cpu);
2105 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
2106 
2107 #else /* !CONFIG_NUMA: */
2108 
sched_init_numa(int offline_node)2109 static inline void sched_init_numa(int offline_node) { }
sched_update_numa(int cpu,bool online)2110 static inline void sched_update_numa(int cpu, bool online) { }
sched_domains_numa_masks_set(unsigned int cpu)2111 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
sched_domains_numa_masks_clear(unsigned int cpu)2112 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
2113 
sched_numa_find_closest(const struct cpumask * cpus,int cpu)2114 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
2115 {
2116 	return nr_cpu_ids;
2117 }
2118 
2119 #endif /* !CONFIG_NUMA */
2120 
2121 #ifdef CONFIG_NUMA_BALANCING
2122 
2123 /* The regions in numa_faults array from task_struct */
2124 enum numa_faults_stats {
2125 	NUMA_MEM = 0,
2126 	NUMA_CPU,
2127 	NUMA_MEMBUF,
2128 	NUMA_CPUBUF
2129 };
2130 
2131 extern void sched_setnuma(struct task_struct *p, int node);
2132 extern int migrate_task_to(struct task_struct *p, int cpu);
2133 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
2134 			int cpu, int scpu);
2135 extern void init_numa_balancing(u64 clone_flags, struct task_struct *p);
2136 
2137 #else /* !CONFIG_NUMA_BALANCING: */
2138 
2139 static inline void
init_numa_balancing(u64 clone_flags,struct task_struct * p)2140 init_numa_balancing(u64 clone_flags, struct task_struct *p)
2141 {
2142 }
2143 
2144 #endif /* !CONFIG_NUMA_BALANCING */
2145 
2146 int task_llc(const struct task_struct *p);
2147 
2148 static inline void
queue_balance_callback(struct rq * rq,struct balance_callback * head,void (* func)(struct rq * rq))2149 queue_balance_callback(struct rq *rq,
2150 		       struct balance_callback *head,
2151 		       void (*func)(struct rq *rq))
2152 {
2153 	lockdep_assert_rq_held(rq);
2154 
2155 	/*
2156 	 * Don't (re)queue an already queued item; nor queue anything when
2157 	 * balance_push() is active, see the comment with
2158 	 * balance_push_callback.
2159 	 */
2160 	if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
2161 		return;
2162 
2163 	head->func = func;
2164 	head->next = rq->balance_callback;
2165 	rq->balance_callback = head;
2166 }
2167 
2168 #define rcu_dereference_sched_domain(p) \
2169 	rcu_dereference_all_check((p), lockdep_is_held(&sched_domains_mutex))
2170 
2171 /*
2172  * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
2173  * See destroy_sched_domains: call_rcu for details.
2174  *
2175  * The domain tree of any CPU may only be accessed from within
2176  * preempt-disabled sections.
2177  */
2178 #define for_each_domain(cpu, __sd) \
2179 	for (__sd = rcu_dereference_sched_domain(cpu_rq(cpu)->sd); \
2180 			__sd; __sd = __sd->parent)
2181 
2182 /* A mask of all the SD flags that have the SDF_SHARED_CHILD metaflag */
2183 #define SD_FLAG(name, mflags) (name * !!((mflags) & SDF_SHARED_CHILD)) |
2184 static const unsigned int SD_SHARED_CHILD_MASK =
2185 #include <linux/sched/sd_flags.h>
2186 0;
2187 #undef SD_FLAG
2188 
2189 /**
2190  * highest_flag_domain - Return highest sched_domain containing flag.
2191  * @cpu:	The CPU whose highest level of sched domain is to
2192  *		be returned.
2193  * @flag:	The flag to check for the highest sched_domain
2194  *		for the given CPU.
2195  *
2196  * Returns the highest sched_domain of a CPU which contains @flag. If @flag has
2197  * the SDF_SHARED_CHILD metaflag, all the children domains also have @flag.
2198  */
highest_flag_domain(int cpu,int flag)2199 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
2200 {
2201 	struct sched_domain *sd, *hsd = NULL;
2202 
2203 	for_each_domain(cpu, sd) {
2204 		if (sd->flags & flag) {
2205 			hsd = sd;
2206 			continue;
2207 		}
2208 
2209 		/*
2210 		 * Stop the search if @flag is known to be shared at lower
2211 		 * levels. It will not be found further up.
2212 		 */
2213 		if (flag & SD_SHARED_CHILD_MASK)
2214 			break;
2215 	}
2216 
2217 	return hsd;
2218 }
2219 
lowest_flag_domain(int cpu,int flag)2220 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
2221 {
2222 	struct sched_domain *sd;
2223 
2224 	for_each_domain(cpu, sd) {
2225 		if (sd->flags & flag)
2226 			break;
2227 	}
2228 
2229 	return sd;
2230 }
2231 
2232 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
2233 DECLARE_PER_CPU(int, sd_llc_size);
2234 DECLARE_PER_CPU(int, sd_llc_id);
2235 DECLARE_PER_CPU(int, sd_share_id);
2236 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
2237 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_balance_shared);
2238 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
2239 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
2240 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
2241 
2242 extern struct static_key_false sched_asym_cpucapacity;
2243 extern struct static_key_false sched_cluster_active;
2244 
sched_asym_cpucap_active(void)2245 static __always_inline bool sched_asym_cpucap_active(void)
2246 {
2247 	return static_branch_unlikely(&sched_asym_cpucapacity);
2248 }
2249 
2250 struct sched_group_capacity {
2251 	atomic_t		ref;
2252 	/*
2253 	 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
2254 	 * for a single CPU.
2255 	 */
2256 	unsigned long		capacity;
2257 	unsigned long		min_capacity;		/* Min per-CPU capacity in group */
2258 	unsigned long		max_capacity;		/* Max per-CPU capacity in group */
2259 	unsigned long		next_update;
2260 	int			imbalance;		/* XXX unrelated to capacity but shared group state */
2261 
2262 	int			id;
2263 
2264 	unsigned long		cpumask[];		/* Balance mask */
2265 };
2266 
2267 struct sched_group {
2268 	struct sched_group	*next;			/* Must be a circular list */
2269 	atomic_t		ref;
2270 
2271 	unsigned int		group_weight;
2272 	unsigned int		cores;
2273 	struct sched_group_capacity *sgc;
2274 	int			asym_prefer_cpu;	/* CPU of highest priority in group */
2275 	int			flags;
2276 
2277 	/*
2278 	 * The CPUs this group covers.
2279 	 *
2280 	 * NOTE: this field is variable length. (Allocated dynamically
2281 	 * by attaching extra space to the end of the structure,
2282 	 * depending on how many CPUs the kernel has booted up with)
2283 	 */
2284 	unsigned long		cpumask[];
2285 };
2286 
sched_group_span(struct sched_group * sg)2287 static inline struct cpumask *sched_group_span(struct sched_group *sg)
2288 {
2289 	return to_cpumask(sg->cpumask);
2290 }
2291 
2292 /*
2293  * See build_balance_mask().
2294  */
group_balance_mask(struct sched_group * sg)2295 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
2296 {
2297 	return to_cpumask(sg->sgc->cpumask);
2298 }
2299 
2300 extern int group_balance_cpu(struct sched_group *sg);
2301 
2302 extern void update_sched_domain_debugfs(void);
2303 extern void dirty_sched_domain_sysctl(int cpu);
2304 
2305 extern int sched_update_scaling(void);
2306 
task_user_cpus(struct task_struct * p)2307 static inline const struct cpumask *task_user_cpus(struct task_struct *p)
2308 {
2309 	if (!p->user_cpus_ptr)
2310 		return cpu_possible_mask; /* &init_task.cpus_mask */
2311 	return p->user_cpus_ptr;
2312 }
2313 
2314 #ifdef CONFIG_CGROUP_SCHED
2315 
2316 /*
2317  * Return the group to which this tasks belongs.
2318  *
2319  * We cannot use task_css() and friends because the cgroup subsystem
2320  * changes that value before the cgroup_subsys::attach() method is called,
2321  * therefore we cannot pin it and might observe the wrong value.
2322  *
2323  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
2324  * core changes this before calling sched_move_task().
2325  *
2326  * Instead we use a 'copy' which is updated from sched_move_task() while
2327  * holding both task_struct::pi_lock and rq::lock.
2328  */
task_group(struct task_struct * p)2329 static inline struct task_group *task_group(struct task_struct *p)
2330 {
2331 	return p->sched_task_group;
2332 }
2333 
2334 #ifdef CONFIG_FAIR_GROUP_SCHED
2335 /*
2336  * Defined here to be available before stats.h is included, since
2337  * stats.h has dependencies on things defined later in this file.
2338  */
2339 struct cfs_tg_state {
2340 	struct cfs_rq		cfs_rq;
2341 	struct sched_entity	se;
2342 	struct sched_statistics	stats;
2343 } __no_randomize_layout;
2344 
2345 /* Access a specific CPU's cfs_rq from a task group */
tg_cfs_rq(struct task_group * tg,int cpu)2346 static inline struct cfs_rq *tg_cfs_rq(struct task_group *tg, int cpu)
2347 {
2348 	return per_cpu_ptr(tg->cfs_rq, cpu);
2349 }
2350 
tg_se(struct task_group * tg,int cpu)2351 static inline struct sched_entity *tg_se(struct task_group *tg, int cpu)
2352 {
2353 	struct cfs_tg_state *state;
2354 
2355 	if (is_root_task_group(tg))
2356 		return NULL;
2357 
2358 	state = container_of(tg_cfs_rq(tg, cpu), struct cfs_tg_state, cfs_rq);
2359 	return &state->se;
2360 }
2361 
cfs_rq_se(struct cfs_rq * cfs_rq)2362 static inline struct sched_entity *cfs_rq_se(struct cfs_rq *cfs_rq)
2363 {
2364 	struct cfs_tg_state *state;
2365 
2366 	if (is_root_task_group(cfs_rq->tg))
2367 		return NULL;
2368 
2369 	state = container_of(cfs_rq, struct cfs_tg_state, cfs_rq);
2370 	return &state->se;
2371 }
2372 #endif
2373 
2374 /* 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)2375 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
2376 {
2377 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
2378 	struct task_group *tg = task_group(p);
2379 #endif
2380 
2381 #ifdef CONFIG_FAIR_GROUP_SCHED
2382 	set_task_rq_fair(&p->se, p->se.cfs_rq, tg_cfs_rq(tg, cpu));
2383 	p->se.cfs_rq = tg_cfs_rq(tg, cpu);
2384 	p->se.parent = tg_se(tg, cpu);
2385 	p->se.depth = p->se.parent ? p->se.parent->depth + 1 : 0;
2386 #endif
2387 
2388 #ifdef CONFIG_RT_GROUP_SCHED
2389 	/*
2390 	 * p->rt.rt_rq is NULL initially and it is easier to assign
2391 	 * root_task_group's rt_rq than switching in rt_rq_of_se()
2392 	 * Clobbers tg(!)
2393 	 */
2394 	if (!rt_group_sched_enabled())
2395 		tg = &root_task_group;
2396 	p->rt.rt_rq  = tg->rt_rq[cpu];
2397 	p->rt.parent = tg->rt_se[cpu];
2398 #endif /* CONFIG_RT_GROUP_SCHED */
2399 }
2400 
2401 #else /* !CONFIG_CGROUP_SCHED: */
2402 
set_task_rq(struct task_struct * p,unsigned int cpu)2403 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
2404 
task_group(struct task_struct * p)2405 static inline struct task_group *task_group(struct task_struct *p)
2406 {
2407 	return NULL;
2408 }
2409 
2410 #endif /* !CONFIG_CGROUP_SCHED */
2411 
__set_task_cpu(struct task_struct * p,unsigned int cpu)2412 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
2413 {
2414 	set_task_rq(p, cpu);
2415 #ifdef CONFIG_SMP
2416 	/*
2417 	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
2418 	 * successfully executed on another CPU. We must ensure that updates of
2419 	 * per-task data have been completed by this moment.
2420 	 */
2421 	smp_wmb();
2422 	WRITE_ONCE(task_thread_info(p)->cpu, cpu);
2423 	p->wake_cpu = cpu;
2424 	rseq_sched_set_ids_changed(p);
2425 #endif /* CONFIG_SMP */
2426 }
2427 
2428 /*
2429  * Tunables:
2430  */
2431 
2432 #define SCHED_FEAT(name, enabled)	\
2433 	__SCHED_FEAT_##name ,
2434 
2435 enum {
2436 #include "features.h"
2437 	__SCHED_FEAT_NR,
2438 };
2439 
2440 #undef SCHED_FEAT
2441 
2442 /*
2443  * To support run-time toggling of sched features, all the translation units
2444  * (but core.c) reference the sysctl_sched_features defined in core.c.
2445  */
2446 extern __read_mostly unsigned int sysctl_sched_features;
2447 
2448 #ifdef CONFIG_JUMP_LABEL
2449 
2450 #define SCHED_FEAT(name, enabled)					\
2451 static __always_inline bool static_branch_##name(struct static_key *key) \
2452 {									\
2453 	return static_key_##enabled(key);				\
2454 }
2455 
2456 #include "features.h"
2457 #undef SCHED_FEAT
2458 
2459 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
2460 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
2461 
2462 #else /* !CONFIG_JUMP_LABEL: */
2463 
2464 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2465 
2466 #endif /* !CONFIG_JUMP_LABEL */
2467 
2468 extern struct static_key_false sched_numa_balancing;
2469 extern struct static_key_false sched_schedstats;
2470 
global_rt_period(void)2471 static inline u64 global_rt_period(void)
2472 {
2473 	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
2474 }
2475 
global_rt_runtime(void)2476 static inline u64 global_rt_runtime(void)
2477 {
2478 	if (sysctl_sched_rt_runtime < 0)
2479 		return RUNTIME_INF;
2480 
2481 	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
2482 }
2483 
2484 /*
2485  * Is p the current execution context?
2486  */
task_current(struct rq * rq,struct task_struct * p)2487 static inline int task_current(struct rq *rq, struct task_struct *p)
2488 {
2489 	return rq->curr == p;
2490 }
2491 
2492 /*
2493  * Is p the current scheduling context?
2494  *
2495  * Note that it might be the current execution context at the same time if
2496  * rq->curr == rq->donor == p.
2497  */
task_current_donor(struct rq * rq,struct task_struct * p)2498 static inline int task_current_donor(struct rq *rq, struct task_struct *p)
2499 {
2500 	return rq->donor == p;
2501 }
2502 
task_is_blocked(struct task_struct * p)2503 static inline bool task_is_blocked(struct task_struct *p)
2504 {
2505 	if (!sched_proxy_exec())
2506 		return false;
2507 
2508 	return !!p->blocked_on;
2509 }
2510 
task_on_cpu(struct rq * rq,struct task_struct * p)2511 static inline int task_on_cpu(struct rq *rq, struct task_struct *p)
2512 {
2513 	return p->on_cpu;
2514 }
2515 
task_on_rq_queued(struct task_struct * p)2516 static inline int task_on_rq_queued(struct task_struct *p)
2517 {
2518 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_QUEUED;
2519 }
2520 
task_on_rq_migrating(struct task_struct * p)2521 static inline int task_on_rq_migrating(struct task_struct *p)
2522 {
2523 	return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
2524 }
2525 
2526 /* Wake flags. The first three directly map to some SD flag value */
2527 #define WF_EXEC			0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
2528 #define WF_FORK			0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
2529 #define WF_TTWU			0x08 /* Wakeup;            maps to SD_BALANCE_WAKE */
2530 
2531 #define WF_SYNC			0x10 /* Waker goes to sleep after wakeup */
2532 #define WF_MIGRATED		0x20 /* Internal use, task got migrated */
2533 #define WF_CURRENT_CPU		0x40 /* Prefer to move the wakee to the current CPU. */
2534 #define WF_RQ_SELECTED		0x80 /* ->select_task_rq() was called */
2535 
2536 static_assert(WF_EXEC == SD_BALANCE_EXEC);
2537 static_assert(WF_FORK == SD_BALANCE_FORK);
2538 static_assert(WF_TTWU == SD_BALANCE_WAKE);
2539 
2540 /*
2541  * To aid in avoiding the subversion of "niceness" due to uneven distribution
2542  * of tasks with abnormal "nice" values across CPUs the contribution that
2543  * each task makes to its run queue's load is weighted according to its
2544  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
2545  * scaled version of the new time slice allocation that they receive on time
2546  * slice expiry etc.
2547  */
2548 
2549 #define WEIGHT_IDLEPRIO		3
2550 #define WMULT_IDLEPRIO		1431655765
2551 
2552 extern const int		sched_prio_to_weight[40];
2553 extern const u32		sched_prio_to_wmult[40];
2554 
2555 /*
2556  * {de,en}queue flags:
2557  *
2558  * SLEEP/WAKEUP - task is no-longer/just-became runnable
2559  *
2560  * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
2561  *                are in a known state which allows modification. Such pairs
2562  *                should preserve as much state as possible.
2563  *
2564  * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
2565  *        in the runqueue. IOW the priority is allowed to change. Callers
2566  *        must expect to deal with balance callbacks.
2567  *
2568  * NOCLOCK - skip the update_rq_clock() (avoids double updates)
2569  *
2570  * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE)
2571  *
2572  * DELAYED - de/re-queue a sched_delayed task
2573  *
2574  * CLASS - going to update p->sched_class; makes sched_change call the
2575  *         various switch methods.
2576  *
2577  * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
2578  * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
2579  * ENQUEUE_MIGRATED  - the task was migrated during wakeup
2580  * ENQUEUE_RQ_SELECTED - ->select_task_rq() was called
2581  *
2582  * XXX SAVE/RESTORE in combination with CLASS doesn't really make sense, but
2583  * SCHED_DEADLINE seems to rely on this for now.
2584  */
2585 
2586 #define DEQUEUE_SLEEP		0x0001 /* Matches ENQUEUE_WAKEUP */
2587 #define DEQUEUE_SAVE		0x0002 /* Matches ENQUEUE_RESTORE */
2588 #define DEQUEUE_MOVE		0x0004 /* Matches ENQUEUE_MOVE */
2589 #define DEQUEUE_NOCLOCK		0x0008 /* Matches ENQUEUE_NOCLOCK */
2590 
2591 #define DEQUEUE_MIGRATING	0x0010 /* Matches ENQUEUE_MIGRATING */
2592 #define DEQUEUE_DELAYED		0x0020 /* Matches ENQUEUE_DELAYED */
2593 #define DEQUEUE_CLASS		0x0040 /* Matches ENQUEUE_CLASS */
2594 
2595 #define DEQUEUE_SPECIAL		0x00010000
2596 #define DEQUEUE_THROTTLE	0x00020000
2597 
2598 #define ENQUEUE_WAKEUP		0x0001
2599 #define ENQUEUE_RESTORE		0x0002
2600 #define ENQUEUE_MOVE		0x0004
2601 #define ENQUEUE_NOCLOCK		0x0008
2602 
2603 #define ENQUEUE_MIGRATING	0x0010
2604 #define ENQUEUE_DELAYED		0x0020
2605 #define ENQUEUE_CLASS		0x0040
2606 
2607 #define ENQUEUE_HEAD		0x00010000
2608 #define ENQUEUE_REPLENISH	0x00020000
2609 #define ENQUEUE_MIGRATED	0x00040000
2610 #define ENQUEUE_INITIAL		0x00080000
2611 #define ENQUEUE_RQ_SELECTED	0x00100000
2612 #define ENQUEUE_QUEUED		0x00200000
2613 
2614 #define RETRY_TASK		((void *)-1UL)
2615 
2616 struct affinity_context {
2617 	const struct cpumask	*new_mask;
2618 	struct cpumask		*user_mask;
2619 	unsigned int		flags;
2620 };
2621 
2622 extern s64 update_curr_common(struct rq *rq);
2623 
2624 struct sched_class {
2625 
2626 #ifdef CONFIG_UCLAMP_TASK
2627 	int uclamp_enabled;
2628 #endif
2629 
2630 	/*
2631 	 * move_queued_task/activate_task/enqueue_task: rq->lock
2632 	 * ttwu_do_activate/activate_task/enqueue_task: rq->lock
2633 	 * wake_up_new_task/activate_task/enqueue_task: task_rq_lock
2634 	 * ttwu_runnable/enqueue_task: task_rq_lock
2635 	 * proxy_task_current: rq->lock
2636 	 * sched_change_end
2637 	 */
2638 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
2639 	/*
2640 	 * move_queued_task/deactivate_task/dequeue_task: rq->lock
2641 	 * __schedule/block_task/dequeue_task: rq->lock
2642 	 * proxy_task_current: rq->lock
2643 	 * wait_task_inactive: task_rq_lock
2644 	 * sched_change_begin
2645 	 */
2646 	bool (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
2647 
2648 	/*
2649 	 * do_sched_yield: rq->lock
2650 	 */
2651 	void (*yield_task)   (struct rq *rq);
2652 	/*
2653 	 * yield_to: rq->lock (double)
2654 	 */
2655 	bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
2656 
2657 	/*
2658 	 * move_queued_task: rq->lock
2659 	 * __migrate_swap_task: rq->lock
2660 	 * ttwu_do_activate: rq->lock
2661 	 * ttwu_runnable: task_rq_lock
2662 	 * wake_up_new_task: task_rq_lock
2663 	 */
2664 	void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags);
2665 
2666 	/*
2667 	 * schedule/pick_next_task/prev_balance: rq->lock
2668 	 */
2669 	int (*balance)(struct rq *rq, struct rq_flags *rf);
2670 
2671 	/*
2672 	 * schedule/pick_next_task: rq->lock
2673 	 */
2674 	struct task_struct *(*pick_task)(struct rq *rq, struct rq_flags *rf);
2675 
2676 	/*
2677 	 * sched_change:
2678 	 * __schedule: rq->lock
2679 	 */
2680 	void (*put_prev_task)(struct rq *rq, struct task_struct *p, struct task_struct *next);
2681 	void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
2682 
2683 	/*
2684 	 * select_task_rq: p->pi_lock
2685 	 * sched_exec: p->pi_lock
2686 	 */
2687 	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
2688 
2689 	/*
2690 	 * set_task_cpu: p->pi_lock || rq->lock (ttwu like)
2691 	 */
2692 	void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
2693 
2694 	/*
2695 	 * ttwu_do_activate: rq->lock
2696 	 * wake_up_new_task: task_rq_lock
2697 	 */
2698 	void (*task_woken)(struct rq *this_rq, struct task_struct *task);
2699 
2700 	/*
2701 	 * do_set_cpus_allowed: task_rq_lock + sched_change
2702 	 */
2703 	void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx);
2704 
2705 	/*
2706 	 * sched_set_rq_{on,off}line: rq->lock
2707 	 */
2708 	void (*rq_online)(struct rq *rq);
2709 	void (*rq_offline)(struct rq *rq);
2710 
2711 	/*
2712 	 * push_cpu_stop: p->pi_lock && rq->lock
2713 	 */
2714 	struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
2715 
2716 	/*
2717 	 * hrtick: rq->lock
2718 	 * sched_tick: rq->lock
2719 	 * sched_tick_remote: rq->lock
2720 	 */
2721 	void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
2722 	/*
2723 	 * sched_cgroup_fork: p->pi_lock
2724 	 */
2725 	void (*task_fork)(struct task_struct *p);
2726 	/*
2727 	 * finish_task_switch: no locks
2728 	 */
2729 	void (*task_dead)(struct task_struct *p);
2730 
2731 	/*
2732 	 * sched_change
2733 	 */
2734 	void (*switching_from)(struct rq *this_rq, struct task_struct *task);
2735 	void (*switched_from) (struct rq *this_rq, struct task_struct *task);
2736 	void (*switching_to)  (struct rq *this_rq, struct task_struct *task);
2737 	void (*switched_to)   (struct rq *this_rq, struct task_struct *task);
2738 	u64  (*get_prio)     (struct rq *this_rq, struct task_struct *task);
2739 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
2740 			      u64 oldprio);
2741 
2742 	/*
2743 	 * set_load_weight: task_rq_lock + sched_change
2744 	 * __setscheduler_parms: task_rq_lock + sched_change
2745 	 */
2746 	void (*reweight_task)(struct rq *this_rq, struct task_struct *task,
2747 			      const struct load_weight *lw);
2748 
2749 	/*
2750 	 * sched_rr_get_interval: task_rq_lock
2751 	 */
2752 	unsigned int (*get_rr_interval)(struct rq *rq,
2753 					struct task_struct *task);
2754 
2755 	/*
2756 	 * task_sched_runtime: task_rq_lock
2757 	 */
2758 	void (*update_curr)(struct rq *rq);
2759 
2760 #ifdef CONFIG_FAIR_GROUP_SCHED
2761 	/*
2762 	 * sched_change_group: task_rq_lock + sched_change
2763 	 */
2764 	void (*task_change_group)(struct task_struct *p);
2765 #endif
2766 
2767 #ifdef CONFIG_SCHED_CORE
2768 	/*
2769 	 * pick_next_task: rq->lock
2770 	 * try_steal_cookie: rq->lock (double)
2771 	 */
2772 	int (*task_is_throttled)(struct task_struct *p, int cpu);
2773 #endif
2774 };
2775 
put_prev_task(struct rq * rq,struct task_struct * prev)2776 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
2777 {
2778 	WARN_ON_ONCE(rq->donor != prev);
2779 	prev->sched_class->put_prev_task(rq, prev, NULL);
2780 }
2781 
set_next_task(struct rq * rq,struct task_struct * next)2782 static inline void set_next_task(struct rq *rq, struct task_struct *next)
2783 {
2784 	next->sched_class->set_next_task(rq, next, false);
2785 }
2786 
2787 static inline void
__put_prev_set_next_dl_server(struct rq * rq,struct task_struct * prev,struct task_struct * next)2788 __put_prev_set_next_dl_server(struct rq *rq,
2789 			      struct task_struct *prev,
2790 			      struct task_struct *next)
2791 {
2792 	prev->dl_server = NULL;
2793 	next->dl_server = rq->dl_server;
2794 	rq->dl_server = NULL;
2795 }
2796 
put_prev_set_next_task(struct rq * rq,struct task_struct * prev,struct task_struct * next)2797 static inline void put_prev_set_next_task(struct rq *rq,
2798 					  struct task_struct *prev,
2799 					  struct task_struct *next)
2800 {
2801 	WARN_ON_ONCE(rq->donor != prev);
2802 
2803 	__put_prev_set_next_dl_server(rq, prev, next);
2804 
2805 	if (next == prev)
2806 		return;
2807 
2808 	prev->sched_class->put_prev_task(rq, prev, next);
2809 	next->sched_class->set_next_task(rq, next, true);
2810 }
2811 
2812 /*
2813  * Helper to define a sched_class instance; each one is placed in a separate
2814  * section which is ordered by the linker script:
2815  *
2816  *   include/asm-generic/vmlinux.lds.h
2817  *
2818  * *CAREFUL* they are laid out in *REVERSE* order!!!
2819  *
2820  * Also enforce alignment on the instance, not the type, to guarantee layout.
2821  */
2822 #define DEFINE_SCHED_CLASS(name) \
2823 const struct sched_class name##_sched_class \
2824 	__aligned(__alignof__(struct sched_class)) \
2825 	__section("__" #name "_sched_class")
2826 
2827 /* Defined in include/asm-generic/vmlinux.lds.h */
2828 extern struct sched_class __sched_class_highest[];
2829 extern struct sched_class __sched_class_lowest[];
2830 
2831 extern const struct sched_class stop_sched_class;
2832 extern const struct sched_class dl_sched_class;
2833 extern const struct sched_class rt_sched_class;
2834 extern const struct sched_class fair_sched_class;
2835 extern const struct sched_class idle_sched_class;
2836 
2837 /*
2838  * Iterate only active classes. SCX can take over all fair tasks or be
2839  * completely disabled. If the former, skip fair. If the latter, skip SCX.
2840  */
next_active_class(const struct sched_class * class)2841 static inline const struct sched_class *next_active_class(const struct sched_class *class)
2842 {
2843 	class++;
2844 #ifdef CONFIG_SCHED_CLASS_EXT
2845 	if (scx_switched_all() && class == &fair_sched_class)
2846 		class++;
2847 	if (!scx_enabled() && class == &ext_sched_class)
2848 		class++;
2849 #endif
2850 	return class;
2851 }
2852 
2853 #define for_class_range(class, _from, _to) \
2854 	for (class = (_from); class < (_to); class++)
2855 
2856 #define for_each_class(class) \
2857 	for_class_range(class, __sched_class_highest, __sched_class_lowest)
2858 
2859 #define for_active_class_range(class, _from, _to)				\
2860 	for (class = (_from); class != (_to); class = next_active_class(class))
2861 
2862 #define for_each_active_class(class)						\
2863 	for_active_class_range(class, __sched_class_highest, __sched_class_lowest)
2864 
2865 #define sched_class_above(_a, _b)	((_a) < (_b))
2866 
rq_modified_begin(struct rq * rq,const struct sched_class * class)2867 static inline void rq_modified_begin(struct rq *rq, const struct sched_class *class)
2868 {
2869 	if (sched_class_above(rq->next_class, class))
2870 		rq->next_class = class;
2871 }
2872 
rq_modified_above(struct rq * rq,const struct sched_class * class)2873 static inline bool rq_modified_above(struct rq *rq, const struct sched_class *class)
2874 {
2875 	return sched_class_above(rq->next_class, class);
2876 }
2877 
sched_stop_runnable(struct rq * rq)2878 static inline bool sched_stop_runnable(struct rq *rq)
2879 {
2880 	return rq->stop && task_on_rq_queued(rq->stop);
2881 }
2882 
sched_dl_runnable(struct rq * rq)2883 static inline bool sched_dl_runnable(struct rq *rq)
2884 {
2885 	return rq->dl.dl_nr_running > 0;
2886 }
2887 
sched_rt_runnable(struct rq * rq)2888 static inline bool sched_rt_runnable(struct rq *rq)
2889 {
2890 	return rq->rt.rt_queued > 0;
2891 }
2892 
sched_fair_runnable(struct rq * rq)2893 static inline bool sched_fair_runnable(struct rq *rq)
2894 {
2895 	return rq->cfs.nr_queued > 0;
2896 }
2897 
2898 extern struct task_struct *pick_task_fair(struct rq *rq, struct rq_flags *rf);
2899 extern struct task_struct *pick_task_idle(struct rq *rq, struct rq_flags *rf);
2900 
2901 #define SCA_CHECK		0x01
2902 #define SCA_MIGRATE_DISABLE	0x02
2903 #define SCA_MIGRATE_ENABLE	0x04
2904 #define SCA_USER		0x08
2905 
2906 extern void update_group_capacity(struct sched_domain *sd, int cpu);
2907 
2908 extern void sched_balance_trigger(struct rq *rq);
2909 
2910 extern int __set_cpus_allowed_ptr(struct task_struct *p, struct affinity_context *ctx);
2911 extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx);
2912 
task_allowed_on_cpu(struct task_struct * p,int cpu)2913 static inline bool task_allowed_on_cpu(struct task_struct *p, int cpu)
2914 {
2915 	/* When not in the task's cpumask, no point in looking further. */
2916 	if (!cpumask_test_cpu(cpu, p->cpus_ptr))
2917 		return false;
2918 
2919 	/* Can @cpu run a user thread? */
2920 	if (!(p->flags & PF_KTHREAD) && !task_cpu_possible(cpu, p))
2921 		return false;
2922 
2923 	return true;
2924 }
2925 
alloc_user_cpus_ptr(int node)2926 static inline cpumask_t *alloc_user_cpus_ptr(int node)
2927 {
2928 	/*
2929 	 * See set_cpus_allowed_force() above for the rcu_head usage.
2930 	 */
2931 	int size = max_t(int, cpumask_size(), sizeof(struct rcu_head));
2932 
2933 	return kmalloc_node(size, GFP_KERNEL, node);
2934 }
2935 
get_push_task(struct rq * rq)2936 static inline struct task_struct *get_push_task(struct rq *rq)
2937 {
2938 	struct task_struct *p = rq->donor;
2939 
2940 	lockdep_assert_rq_held(rq);
2941 
2942 	if (rq->push_busy)
2943 		return NULL;
2944 
2945 	if (p->nr_cpus_allowed == 1)
2946 		return NULL;
2947 
2948 	if (p->migration_disabled)
2949 		return NULL;
2950 
2951 	rq->push_busy = true;
2952 	return get_task_struct(p);
2953 }
2954 
2955 extern int push_cpu_stop(void *arg);
2956 
2957 #ifdef CONFIG_CPU_IDLE
2958 
idle_set_state(struct rq * rq,struct cpuidle_state * idle_state)2959 static inline void idle_set_state(struct rq *rq,
2960 				  struct cpuidle_state *idle_state)
2961 {
2962 	rq->idle_state = idle_state;
2963 }
2964 
idle_get_state(struct rq * rq)2965 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2966 {
2967 	lockdep_assert(rcu_read_lock_any_held());
2968 
2969 	return rq->idle_state;
2970 }
2971 
2972 #else /* !CONFIG_CPU_IDLE: */
2973 
idle_set_state(struct rq * rq,struct cpuidle_state * idle_state)2974 static inline void idle_set_state(struct rq *rq,
2975 				  struct cpuidle_state *idle_state)
2976 {
2977 }
2978 
idle_get_state(struct rq * rq)2979 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2980 {
2981 	return NULL;
2982 }
2983 
2984 #endif /* !CONFIG_CPU_IDLE */
2985 
2986 extern void schedule_idle(void);
2987 asmlinkage void schedule_user(void);
2988 
2989 extern void sysrq_sched_debug_show(void);
2990 extern void sched_init_granularity(void);
2991 extern void update_max_interval(void);
2992 
2993 extern void init_sched_dl_class(void);
2994 extern void init_sched_rt_class(void);
2995 extern void init_sched_fair_class(void);
2996 
2997 extern void resched_curr(struct rq *rq);
2998 extern void resched_curr_lazy(struct rq *rq);
2999 extern void resched_cpu(int cpu);
3000 
3001 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
3002 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq);
3003 
3004 extern void init_dl_entity(struct sched_dl_entity *dl_se);
3005 
3006 extern void init_cfs_throttle_work(struct task_struct *p);
3007 
3008 #define BW_SHIFT		20
3009 #define BW_UNIT			(1 << BW_SHIFT)
3010 #define RATIO_SHIFT		8
3011 #define MAX_BW_BITS		(64 - BW_SHIFT)
3012 #define MAX_BW			((1ULL << MAX_BW_BITS) - 1)
3013 
3014 extern u64 to_ratio(u64 period, u64 runtime);
3015 
3016 extern void init_entity_runnable_average(struct sched_entity *se);
3017 extern void post_init_entity_util_avg(struct task_struct *p);
3018 
3019 #ifdef CONFIG_NO_HZ_FULL
3020 extern bool sched_can_stop_tick(struct rq *rq);
3021 extern int __init sched_tick_offload_init(void);
3022 
3023 /*
3024  * Tick may be needed by tasks in the runqueue depending on their policy and
3025  * requirements. If tick is needed, lets send the target an IPI to kick it out of
3026  * nohz mode if necessary.
3027  */
sched_update_tick_dependency(struct rq * rq)3028 static inline void sched_update_tick_dependency(struct rq *rq)
3029 {
3030 	int cpu = cpu_of(rq);
3031 
3032 	if (!tick_nohz_full_cpu(cpu))
3033 		return;
3034 
3035 	if (sched_can_stop_tick(rq))
3036 		tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
3037 	else
3038 		tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
3039 }
3040 #else /* !CONFIG_NO_HZ_FULL: */
sched_tick_offload_init(void)3041 static inline int sched_tick_offload_init(void) { return 0; }
sched_update_tick_dependency(struct rq * rq)3042 static inline void sched_update_tick_dependency(struct rq *rq) { }
3043 #endif /* !CONFIG_NO_HZ_FULL */
3044 
add_nr_running(struct rq * rq,unsigned count)3045 static inline void add_nr_running(struct rq *rq, unsigned count)
3046 {
3047 	unsigned prev_nr = rq->nr_running;
3048 
3049 	rq->nr_running = prev_nr + count;
3050 	if (trace_sched_update_nr_running_tp_enabled()) {
3051 		call_trace_sched_update_nr_running(rq, count);
3052 	}
3053 
3054 	if (prev_nr < 2 && rq->nr_running >= 2)
3055 		set_rd_overloaded(rq->rd, 1);
3056 
3057 	sched_update_tick_dependency(rq);
3058 }
3059 
sub_nr_running(struct rq * rq,unsigned count)3060 static inline void sub_nr_running(struct rq *rq, unsigned count)
3061 {
3062 	rq->nr_running -= count;
3063 	if (trace_sched_update_nr_running_tp_enabled()) {
3064 		call_trace_sched_update_nr_running(rq, -count);
3065 	}
3066 
3067 	/* Check if we still need preemption */
3068 	sched_update_tick_dependency(rq);
3069 }
3070 
__block_task(struct rq * rq,struct task_struct * p)3071 static inline void __block_task(struct rq *rq, struct task_struct *p)
3072 {
3073 	if (p->sched_contributes_to_load)
3074 		rq->nr_uninterruptible++;
3075 
3076 	if (p->in_iowait) {
3077 		atomic_inc(&rq->nr_iowait);
3078 		delayacct_blkio_start();
3079 	}
3080 
3081 	ASSERT_EXCLUSIVE_WRITER(p->on_rq);
3082 
3083 	/*
3084 	 * The moment this write goes through, ttwu() can swoop in and migrate
3085 	 * this task, rendering our rq->__lock ineffective.
3086 	 *
3087 	 * __schedule()				try_to_wake_up()
3088 	 *   LOCK rq->__lock			  LOCK p->pi_lock
3089 	 *   pick_next_task()
3090 	 *     pick_next_task_fair()
3091 	 *       pick_next_entity()
3092 	 *         dequeue_entities()
3093 	 *           __block_task()
3094 	 *             RELEASE p->on_rq = 0	  if (p->on_rq && ...)
3095 	 *					    break;
3096 	 *
3097 	 *					  ACQUIRE (after ctrl-dep)
3098 	 *
3099 	 *					  cpu = select_task_rq();
3100 	 *					  set_task_cpu(p, cpu);
3101 	 *					  ttwu_queue()
3102 	 *					    ttwu_do_activate()
3103 	 *					      LOCK rq->__lock
3104 	 *					      activate_task()
3105 	 *					        STORE p->on_rq = 1
3106 	 *   UNLOCK rq->__lock
3107 	 *
3108 	 * Callers must ensure to not reference @p after this -- we no longer
3109 	 * own it.
3110 	 */
3111 	smp_store_release(&p->on_rq, 0);
3112 }
3113 
3114 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
3115 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
3116 
3117 extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags);
3118 
3119 /*
3120  * attach_task() -- attach the task detached by detach_task() to its new rq.
3121  */
attach_task(struct rq * rq,struct task_struct * p)3122 static inline void attach_task(struct rq *rq, struct task_struct *p)
3123 {
3124 	lockdep_assert_rq_held(rq);
3125 
3126 	WARN_ON_ONCE(task_rq(p) != rq);
3127 	activate_task(rq, p, ENQUEUE_NOCLOCK);
3128 	wakeup_preempt(rq, p, 0);
3129 }
3130 
3131 /*
3132  * attach_one_task() -- attaches the task returned from detach_one_task() to
3133  * its new rq.
3134  */
attach_one_task(struct rq * rq,struct task_struct * p)3135 static inline void attach_one_task(struct rq *rq, struct task_struct *p)
3136 {
3137 	guard(rq_lock)(rq);
3138 	update_rq_clock(rq);
3139 	attach_task(rq, p);
3140 }
3141 
3142 #ifdef CONFIG_PREEMPT_RT
3143 # define SCHED_NR_MIGRATE_BREAK 8
3144 #else
3145 # define SCHED_NR_MIGRATE_BREAK 32
3146 #endif
3147 
3148 extern __read_mostly unsigned int sysctl_sched_nr_migrate;
3149 extern __read_mostly unsigned int sysctl_sched_migration_cost;
3150 
3151 extern unsigned int sysctl_sched_base_slice;
3152 
3153 extern int sysctl_resched_latency_warn_ms;
3154 extern int sysctl_resched_latency_warn_once;
3155 
3156 extern unsigned int sysctl_sched_tunable_scaling;
3157 
3158 extern unsigned int sysctl_numa_balancing_scan_delay;
3159 extern unsigned int sysctl_numa_balancing_scan_period_min;
3160 extern unsigned int sysctl_numa_balancing_scan_period_max;
3161 extern unsigned int sysctl_numa_balancing_scan_size;
3162 extern unsigned int sysctl_numa_balancing_hot_threshold;
3163 
3164 #ifdef CONFIG_SCHED_HRTICK
3165 
3166 /*
3167  * Use hrtick when:
3168  *  - enabled by features
3169  *  - hrtimer is actually high res
3170  */
hrtick_enabled(struct rq * rq)3171 static inline bool hrtick_enabled(struct rq *rq)
3172 {
3173 	return cpu_active(cpu_of(rq)) && hrtimer_highres_enabled();
3174 }
3175 
hrtick_enabled_fair(struct rq * rq)3176 static inline bool hrtick_enabled_fair(struct rq *rq)
3177 {
3178 	return sched_feat(HRTICK) && hrtick_enabled(rq);
3179 }
3180 
hrtick_enabled_dl(struct rq * rq)3181 static inline bool hrtick_enabled_dl(struct rq *rq)
3182 {
3183 	return sched_feat(HRTICK_DL) && hrtick_enabled(rq);
3184 }
3185 
3186 extern void hrtick_start(struct rq *rq, u64 delay);
hrtick_active(struct rq * rq)3187 static inline bool hrtick_active(struct rq *rq)
3188 {
3189 	return hrtimer_active(&rq->hrtick_timer);
3190 }
3191 
3192 #else /* !CONFIG_SCHED_HRTICK: */
hrtick_enabled_fair(struct rq * rq)3193 static inline bool hrtick_enabled_fair(struct rq *rq) { return false; }
hrtick_enabled_dl(struct rq * rq)3194 static inline bool hrtick_enabled_dl(struct rq *rq) { return false; }
hrtick_enabled(struct rq * rq)3195 static inline bool hrtick_enabled(struct rq *rq) { return false; }
3196 #endif /* !CONFIG_SCHED_HRTICK */
3197 
3198 #ifndef arch_scale_freq_tick
arch_scale_freq_tick(void)3199 static __always_inline void arch_scale_freq_tick(void) { }
3200 #endif
3201 
3202 #ifndef arch_scale_freq_capacity
3203 /**
3204  * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
3205  * @cpu: the CPU in question.
3206  *
3207  * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
3208  *
3209  *     f_curr
3210  *     ------ * SCHED_CAPACITY_SCALE
3211  *     f_max
3212  */
3213 static __always_inline
arch_scale_freq_capacity(int cpu)3214 unsigned long arch_scale_freq_capacity(int cpu)
3215 {
3216 	return SCHED_CAPACITY_SCALE;
3217 }
3218 #endif
3219 
3220 /*
3221  * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to
3222  * acquire rq lock instead of rq_lock(). So at the end of these two functions
3223  * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of
3224  * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning.
3225  */
double_rq_clock_clear_update(struct rq * rq1,struct rq * rq2)3226 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2)
3227 {
3228 	rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
3229 	rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
3230 }
3231 
3232 #define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...)				\
3233 __DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__)			\
3234 static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2)	\
3235 	__no_context_analysis								\
3236 { class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t;			\
3237   _lock; return _t; }
3238 #define DECLARE_LOCK_GUARD_2_ATTRS(_name, _lock, _unlock1, _unlock2)			\
3239 static inline class_##_name##_t class_##_name##_constructor(lock_##_name##_t *_T1,	\
3240 							    lock_##_name##_t *_T2) _lock; \
3241 static __always_inline void __class_##_name##_cleanup_ctx1(class_##_name##_t **_T1)	\
3242 	__no_context_analysis _unlock1 { }						\
3243 static __always_inline void __class_##_name##_cleanup_ctx2(class_##_name##_t **_T2)	\
3244 	__no_context_analysis _unlock2 { }
3245 #define WITH_LOCK_GUARD_2_ATTRS(_name, _T1, _T2)					\
3246 	class_##_name##_constructor(_T1, _T2),						\
3247 	*__UNIQUE_ID(unlock1) __cleanup(__class_##_name##_cleanup_ctx1) = (void *)(_T1),\
3248 	*__UNIQUE_ID(unlock2) __cleanup(__class_##_name##_cleanup_ctx2) = (void *)(_T2)
3249 
rq_order_less(struct rq * rq1,struct rq * rq2)3250 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2)
3251 {
3252 #ifdef CONFIG_SCHED_CORE
3253 	/*
3254 	 * In order to not have {0,2},{1,3} turn into into an AB-BA,
3255 	 * order by core-id first and cpu-id second.
3256 	 *
3257 	 * Notably:
3258 	 *
3259 	 *	double_rq_lock(0,3); will take core-0, core-1 lock
3260 	 *	double_rq_lock(1,2); will take core-1, core-0 lock
3261 	 *
3262 	 * when only cpu-id is considered.
3263 	 */
3264 	if (rq1->core->cpu < rq2->core->cpu)
3265 		return true;
3266 	if (rq1->core->cpu > rq2->core->cpu)
3267 		return false;
3268 
3269 	/*
3270 	 * __sched_core_flip() relies on SMT having cpu-id lock order.
3271 	 */
3272 #endif /* CONFIG_SCHED_CORE */
3273 	return rq1->cpu < rq2->cpu;
3274 }
3275 
3276 extern void double_rq_lock(struct rq *rq1, struct rq *rq2)
3277 	__acquires(__rq_lockp(rq1), __rq_lockp(rq2));
3278 
3279 #ifdef CONFIG_PREEMPTION
3280 
3281 /*
3282  * fair double_lock_balance: Safely acquires both rq->locks in a fair
3283  * way at the expense of forcing extra atomic operations in all
3284  * invocations.  This assures that the double_lock is acquired using the
3285  * same underlying policy as the spinlock_t on this architecture, which
3286  * reduces latency compared to the unfair variant below.  However, it
3287  * also adds more overhead and therefore may reduce throughput.
3288  */
_double_lock_balance(struct rq * this_rq,struct rq * busiest)3289 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
3290 	__must_hold(__rq_lockp(this_rq))
3291 	__acquires(__rq_lockp(busiest))
3292 {
3293 	raw_spin_rq_unlock(this_rq);
3294 	double_rq_lock(this_rq, busiest);
3295 
3296 	return 1;
3297 }
3298 
3299 #else /* !CONFIG_PREEMPTION: */
3300 /*
3301  * Unfair double_lock_balance: Optimizes throughput at the expense of
3302  * latency by eliminating extra atomic operations when the locks are
3303  * already in proper order on entry.  This favors lower CPU-ids and will
3304  * grant the double lock to lower CPUs over higher ids under contention,
3305  * regardless of entry order into the function.
3306  */
_double_lock_balance(struct rq * this_rq,struct rq * busiest)3307 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
3308 	__must_hold(__rq_lockp(this_rq))
3309 	__acquires(__rq_lockp(busiest))
3310 {
3311 	if (__rq_lockp(this_rq) == __rq_lockp(busiest)) {
3312 		__acquire(__rq_lockp(busiest)); /* already held */
3313 		double_rq_clock_clear_update(this_rq, busiest);
3314 		return 0;
3315 	}
3316 
3317 	if (likely(raw_spin_rq_trylock(busiest))) {
3318 		double_rq_clock_clear_update(this_rq, busiest);
3319 		return 0;
3320 	}
3321 
3322 	if (rq_order_less(this_rq, busiest)) {
3323 		raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING);
3324 		double_rq_clock_clear_update(this_rq, busiest);
3325 		return 0;
3326 	}
3327 
3328 	raw_spin_rq_unlock(this_rq);
3329 	double_rq_lock(this_rq, busiest);
3330 
3331 	return 1;
3332 }
3333 
3334 #endif /* !CONFIG_PREEMPTION */
3335 
3336 /*
3337  * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
3338  */
double_lock_balance(struct rq * this_rq,struct rq * busiest)3339 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
3340 	__must_hold(__rq_lockp(this_rq))
3341 	__acquires(__rq_lockp(busiest))
3342 {
3343 	lockdep_assert_irqs_disabled();
3344 
3345 	return _double_lock_balance(this_rq, busiest);
3346 }
3347 
double_unlock_balance(struct rq * this_rq,struct rq * busiest)3348 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
3349 	__releases(__rq_lockp(busiest))
3350 {
3351 	if (__rq_lockp(this_rq) != __rq_lockp(busiest))
3352 		raw_spin_rq_unlock(busiest);
3353 	else
3354 		__release(__rq_lockp(busiest)); /* fake release */
3355 	lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_);
3356 }
3357 
double_lock(spinlock_t * l1,spinlock_t * l2)3358 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
3359 	__acquires(l1, l2)
3360 {
3361 	if (l1 > l2)
3362 		swap(l1, l2);
3363 
3364 	spin_lock(l1);
3365 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3366 }
3367 
double_lock_irq(spinlock_t * l1,spinlock_t * l2)3368 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
3369 	__acquires(l1, l2)
3370 {
3371 	if (l1 > l2)
3372 		swap(l1, l2);
3373 
3374 	spin_lock_irq(l1);
3375 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3376 }
3377 
double_raw_lock(raw_spinlock_t * l1,raw_spinlock_t * l2)3378 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
3379 	__acquires(l1, l2)
3380 {
3381 	if (l1 > l2)
3382 		swap(l1, l2);
3383 
3384 	raw_spin_lock(l1);
3385 	raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3386 }
3387 
double_raw_unlock(raw_spinlock_t * l1,raw_spinlock_t * l2)3388 static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2)
3389 	__releases(l1, l2)
3390 {
3391 	raw_spin_unlock(l1);
3392 	raw_spin_unlock(l2);
3393 }
3394 
3395 DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t,
3396 		    double_raw_lock(_T->lock, _T->lock2),
3397 		    double_raw_unlock(_T->lock, _T->lock2))
3398 
3399 DECLARE_LOCK_GUARD_2_ATTRS(double_raw_spinlock,
3400 			   __acquires(_T1, _T2),
3401 			   __releases(*(raw_spinlock_t **)_T1),
3402 			   __releases(*(raw_spinlock_t **)_T2));
3403 #define class_double_raw_spinlock_constructor(_T1, _T2) \
3404 	WITH_LOCK_GUARD_2_ATTRS(double_raw_spinlock, _T1, _T2)
3405 
3406 /*
3407  * double_rq_unlock - safely unlock two runqueues
3408  *
3409  * Note this does not restore interrupts like task_rq_unlock,
3410  * you need to do so manually after calling.
3411  */
double_rq_unlock(struct rq * rq1,struct rq * rq2)3412 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
3413 	__releases(__rq_lockp(rq1), __rq_lockp(rq2))
3414 {
3415 	if (__rq_lockp(rq1) != __rq_lockp(rq2))
3416 		raw_spin_rq_unlock(rq2);
3417 	else
3418 		__release(__rq_lockp(rq2)); /* fake release */
3419 	raw_spin_rq_unlock(rq1);
3420 }
3421 
3422 extern void set_rq_online (struct rq *rq);
3423 extern void set_rq_offline(struct rq *rq);
3424 
3425 extern bool sched_smp_initialized;
3426 
3427 DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq,
3428 		    double_rq_lock(_T->lock, _T->lock2),
3429 		    double_rq_unlock(_T->lock, _T->lock2))
3430 
3431 extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq);
3432 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
3433 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
3434 
3435 extern bool sched_debug_verbose;
3436 
3437 extern void print_cfs_stats(struct seq_file *m, int cpu);
3438 extern void print_rt_stats(struct seq_file *m, int cpu);
3439 extern void print_dl_stats(struct seq_file *m, int cpu);
3440 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
3441 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
3442 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
3443 
3444 extern void resched_latency_warn(int cpu, u64 latency);
3445 
3446 #ifdef CONFIG_NUMA_BALANCING
3447 extern void show_numa_stats(struct task_struct *p, struct seq_file *m);
3448 extern void
3449 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
3450 		 unsigned long tpf, unsigned long gsf, unsigned long gpf);
3451 #endif /* CONFIG_NUMA_BALANCING */
3452 
3453 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
3454 extern void init_rt_rq(struct rt_rq *rt_rq);
3455 extern void init_dl_rq(struct dl_rq *dl_rq);
3456 
3457 extern void cfs_bandwidth_usage_inc(void);
3458 extern void cfs_bandwidth_usage_dec(void);
3459 
3460 #ifdef CONFIG_NO_HZ_COMMON
3461 
3462 #define NOHZ_BALANCE_KICK_BIT	0
3463 #define NOHZ_STATS_KICK_BIT	1
3464 #define NOHZ_NEWILB_KICK_BIT	2
3465 #define NOHZ_NEXT_KICK_BIT	3
3466 
3467 /* Run sched_balance_domains() */
3468 #define NOHZ_BALANCE_KICK	BIT(NOHZ_BALANCE_KICK_BIT)
3469 /* Update blocked load */
3470 #define NOHZ_STATS_KICK		BIT(NOHZ_STATS_KICK_BIT)
3471 /* Update blocked load when entering idle */
3472 #define NOHZ_NEWILB_KICK	BIT(NOHZ_NEWILB_KICK_BIT)
3473 /* Update nohz.next_balance */
3474 #define NOHZ_NEXT_KICK		BIT(NOHZ_NEXT_KICK_BIT)
3475 
3476 #define NOHZ_KICK_MASK		(NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK)
3477 
3478 #define nohz_flags(cpu)		(&cpu_rq(cpu)->nohz_flags)
3479 
3480 extern void nohz_balance_exit_idle(struct rq *rq);
3481 #else /* !CONFIG_NO_HZ_COMMON: */
nohz_balance_exit_idle(struct rq * rq)3482 static inline void nohz_balance_exit_idle(struct rq *rq) { }
3483 #endif /* !CONFIG_NO_HZ_COMMON */
3484 
3485 #ifdef CONFIG_NO_HZ_COMMON
3486 extern void nohz_run_idle_balance(int cpu);
3487 #else
nohz_run_idle_balance(int cpu)3488 static inline void nohz_run_idle_balance(int cpu) { }
3489 #endif
3490 
3491 #include "stats.h"
3492 
3493 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS)
3494 
3495 extern void __sched_core_account_forceidle(struct rq *rq);
3496 
sched_core_account_forceidle(struct rq * rq)3497 static inline void sched_core_account_forceidle(struct rq *rq)
3498 {
3499 	if (schedstat_enabled())
3500 		__sched_core_account_forceidle(rq);
3501 }
3502 
3503 extern void __sched_core_tick(struct rq *rq);
3504 
sched_core_tick(struct rq * rq)3505 static inline void sched_core_tick(struct rq *rq)
3506 {
3507 	if (sched_core_enabled(rq) && schedstat_enabled())
3508 		__sched_core_tick(rq);
3509 }
3510 
3511 #else /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS): */
3512 
sched_core_account_forceidle(struct rq * rq)3513 static inline void sched_core_account_forceidle(struct rq *rq) { }
3514 
sched_core_tick(struct rq * rq)3515 static inline void sched_core_tick(struct rq *rq) { }
3516 
3517 #endif /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS) */
3518 
3519 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
3520 
3521 struct irqtime {
3522 	u64			total;
3523 	u64			tick_delta;
3524 	u64			irq_start_time;
3525 	struct u64_stats_sync	sync;
3526 };
3527 
3528 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
3529 DECLARE_STATIC_KEY_FALSE(sched_clock_irqtime);
3530 
irqtime_enabled(void)3531 static inline int irqtime_enabled(void)
3532 {
3533 	return static_branch_likely(&sched_clock_irqtime);
3534 }
3535 
3536 /*
3537  * Returns the irqtime minus the softirq time computed by ksoftirqd.
3538  * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime
3539  * and never move forward.
3540  */
irq_time_read(int cpu)3541 static inline u64 irq_time_read(int cpu)
3542 {
3543 	struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
3544 	unsigned int seq;
3545 	u64 total;
3546 
3547 	do {
3548 		seq = __u64_stats_fetch_begin(&irqtime->sync);
3549 		total = irqtime->total;
3550 	} while (__u64_stats_fetch_retry(&irqtime->sync, seq));
3551 
3552 	return total;
3553 }
3554 
3555 #else /* !CONFIG_IRQ_TIME_ACCOUNTING: */
3556 
irqtime_enabled(void)3557 static inline int irqtime_enabled(void)
3558 {
3559 	return 0;
3560 }
3561 
3562 #endif /* !CONFIG_IRQ_TIME_ACCOUNTING */
3563 
3564 #ifdef CONFIG_CPU_FREQ
3565 
3566 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
3567 
3568 /**
3569  * cpufreq_update_util - Take a note about CPU utilization changes.
3570  * @rq: Runqueue to carry out the update for.
3571  * @flags: Update reason flags.
3572  *
3573  * This function is called by the scheduler on the CPU whose utilization is
3574  * being updated.
3575  *
3576  * It can only be called from RCU-sched read-side critical sections.
3577  *
3578  * The way cpufreq is currently arranged requires it to evaluate the CPU
3579  * performance state (frequency/voltage) on a regular basis to prevent it from
3580  * being stuck in a completely inadequate performance level for too long.
3581  * That is not guaranteed to happen if the updates are only triggered from CFS
3582  * and DL, though, because they may not be coming in if only RT tasks are
3583  * active all the time (or there are RT tasks only).
3584  *
3585  * As a workaround for that issue, this function is called periodically by the
3586  * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
3587  * but that really is a band-aid.  Going forward it should be replaced with
3588  * solutions targeted more specifically at RT tasks.
3589  */
cpufreq_update_util(struct rq * rq,unsigned int flags)3590 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
3591 {
3592 	struct update_util_data *data;
3593 
3594 	data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
3595 						  cpu_of(rq)));
3596 	if (data)
3597 		data->func(data, rq_clock(rq), flags);
3598 }
3599 #else /* !CONFIG_CPU_FREQ: */
cpufreq_update_util(struct rq * rq,unsigned int flags)3600 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) { }
3601 #endif /* !CONFIG_CPU_FREQ */
3602 
3603 #ifdef arch_scale_freq_capacity
3604 # ifndef arch_scale_freq_invariant
3605 #  define arch_scale_freq_invariant()	true
3606 # endif
3607 #else
3608 # define arch_scale_freq_invariant()	false
3609 #endif
3610 
3611 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
3612 				 unsigned long *min,
3613 				 unsigned long *max);
3614 
3615 unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual,
3616 				 unsigned long min,
3617 				 unsigned long max);
3618 
3619 
3620 /*
3621  * Verify the fitness of task @p to run on @cpu taking into account the
3622  * CPU original capacity and the runtime/deadline ratio of the task.
3623  *
3624  * The function will return true if the original capacity of @cpu is
3625  * greater than or equal to task's deadline density right shifted by
3626  * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise.
3627  */
dl_task_fits_capacity(struct task_struct * p,int cpu)3628 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
3629 {
3630 	unsigned long cap = arch_scale_cpu_capacity(cpu);
3631 
3632 	return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT);
3633 }
3634 
cpu_bw_dl(struct rq * rq)3635 static inline unsigned long cpu_bw_dl(struct rq *rq)
3636 {
3637 	return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
3638 }
3639 
cpu_util_dl(struct rq * rq)3640 static inline unsigned long cpu_util_dl(struct rq *rq)
3641 {
3642 	return READ_ONCE(rq->avg_dl.util_avg);
3643 }
3644 
3645 
3646 extern unsigned long cpu_util_cfs(int cpu);
3647 extern unsigned long cpu_util_cfs_boost(int cpu);
3648 
cpu_util_rt(struct rq * rq)3649 static inline unsigned long cpu_util_rt(struct rq *rq)
3650 {
3651 	return READ_ONCE(rq->avg_rt.util_avg);
3652 }
3653 
3654 #ifdef CONFIG_UCLAMP_TASK
3655 
3656 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
3657 
3658 /*
3659  * When uclamp is compiled in, the aggregation at rq level is 'turned off'
3660  * by default in the fast path and only gets turned on once userspace performs
3661  * an operation that requires it.
3662  *
3663  * Returns true if userspace opted-in to use uclamp and aggregation at rq level
3664  * hence is active.
3665  */
uclamp_is_used(void)3666 static inline bool uclamp_is_used(void)
3667 {
3668 	return static_branch_likely(&sched_uclamp_used);
3669 }
3670 
3671 /*
3672  * Enabling static branches would get the cpus_read_lock(),
3673  * check whether uclamp_is_used before enable it to avoid always
3674  * calling cpus_read_lock(). Because we never disable this
3675  * static key once enable it.
3676  */
sched_uclamp_enable(void)3677 static inline void sched_uclamp_enable(void)
3678 {
3679 	if (!uclamp_is_used())
3680 		static_branch_enable(&sched_uclamp_used);
3681 }
3682 
uclamp_rq_get(struct rq * rq,enum uclamp_id clamp_id)3683 static inline unsigned long uclamp_rq_get(struct rq *rq,
3684 					  enum uclamp_id clamp_id)
3685 {
3686 	return READ_ONCE(rq->uclamp[clamp_id].value);
3687 }
3688 
uclamp_rq_set(struct rq * rq,enum uclamp_id clamp_id,unsigned int value)3689 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id,
3690 				 unsigned int value)
3691 {
3692 	WRITE_ONCE(rq->uclamp[clamp_id].value, value);
3693 }
3694 
uclamp_rq_is_idle(struct rq * rq)3695 static inline bool uclamp_rq_is_idle(struct rq *rq)
3696 {
3697 	return rq->uclamp_flags & UCLAMP_FLAG_IDLE;
3698 }
3699 
3700 /* Is the rq being capped/throttled by uclamp_max? */
uclamp_rq_is_capped(struct rq * rq)3701 static inline bool uclamp_rq_is_capped(struct rq *rq)
3702 {
3703 	unsigned long rq_util;
3704 	unsigned long max_util;
3705 
3706 	if (!uclamp_is_used())
3707 		return false;
3708 
3709 	rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq);
3710 	max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
3711 
3712 	return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util;
3713 }
3714 
3715 #define for_each_clamp_id(clamp_id) \
3716 	for ((clamp_id) = 0; (clamp_id) < UCLAMP_CNT; (clamp_id)++)
3717 
3718 extern unsigned int sysctl_sched_uclamp_util_min_rt_default;
3719 
3720 
uclamp_none(enum uclamp_id clamp_id)3721 static inline unsigned int uclamp_none(enum uclamp_id clamp_id)
3722 {
3723 	if (clamp_id == UCLAMP_MIN)
3724 		return 0;
3725 	return SCHED_CAPACITY_SCALE;
3726 }
3727 
3728 /* Integer rounded range for each bucket */
3729 #define UCLAMP_BUCKET_DELTA DIV_ROUND_CLOSEST(SCHED_CAPACITY_SCALE, UCLAMP_BUCKETS)
3730 
uclamp_bucket_id(unsigned int clamp_value)3731 static inline unsigned int uclamp_bucket_id(unsigned int clamp_value)
3732 {
3733 	return min_t(unsigned int, clamp_value / UCLAMP_BUCKET_DELTA, UCLAMP_BUCKETS - 1);
3734 }
3735 
3736 static inline void
uclamp_se_set(struct uclamp_se * uc_se,unsigned int value,bool user_defined)3737 uclamp_se_set(struct uclamp_se *uc_se, unsigned int value, bool user_defined)
3738 {
3739 	uc_se->value = value;
3740 	uc_se->bucket_id = uclamp_bucket_id(value);
3741 	uc_se->user_defined = user_defined;
3742 }
3743 
3744 #else /* !CONFIG_UCLAMP_TASK: */
3745 
3746 static inline unsigned long
uclamp_eff_value(struct task_struct * p,enum uclamp_id clamp_id)3747 uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id)
3748 {
3749 	if (clamp_id == UCLAMP_MIN)
3750 		return 0;
3751 
3752 	return SCHED_CAPACITY_SCALE;
3753 }
3754 
uclamp_rq_is_capped(struct rq * rq)3755 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; }
3756 
uclamp_is_used(void)3757 static inline bool uclamp_is_used(void)
3758 {
3759 	return false;
3760 }
3761 
sched_uclamp_enable(void)3762 static inline void sched_uclamp_enable(void) {}
3763 
3764 static inline unsigned long
uclamp_rq_get(struct rq * rq,enum uclamp_id clamp_id)3765 uclamp_rq_get(struct rq *rq, enum uclamp_id clamp_id)
3766 {
3767 	if (clamp_id == UCLAMP_MIN)
3768 		return 0;
3769 
3770 	return SCHED_CAPACITY_SCALE;
3771 }
3772 
3773 static inline void
uclamp_rq_set(struct rq * rq,enum uclamp_id clamp_id,unsigned int value)3774 uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, unsigned int value)
3775 {
3776 }
3777 
uclamp_rq_is_idle(struct rq * rq)3778 static inline bool uclamp_rq_is_idle(struct rq *rq)
3779 {
3780 	return false;
3781 }
3782 
3783 #endif /* !CONFIG_UCLAMP_TASK */
3784 
3785 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
3786 
cpu_util_irq(struct rq * rq)3787 static inline unsigned long cpu_util_irq(struct rq *rq)
3788 {
3789 	return READ_ONCE(rq->avg_irq.util_avg);
3790 }
3791 
3792 static inline
scale_irq_capacity(unsigned long util,unsigned long irq,unsigned long max)3793 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3794 {
3795 	util *= (max - irq);
3796 	util /= max;
3797 
3798 	return util;
3799 
3800 }
3801 
3802 #else /* !CONFIG_HAVE_SCHED_AVG_IRQ: */
3803 
cpu_util_irq(struct rq * rq)3804 static inline unsigned long cpu_util_irq(struct rq *rq)
3805 {
3806 	return 0;
3807 }
3808 
3809 static inline
scale_irq_capacity(unsigned long util,unsigned long irq,unsigned long max)3810 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3811 {
3812 	return util;
3813 }
3814 
3815 #endif /* !CONFIG_HAVE_SCHED_AVG_IRQ */
3816 
3817 extern void __setparam_fair(struct task_struct *p, const struct sched_attr *attr);
3818 
3819 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
3820 
3821 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
3822 
3823 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
3824 
sched_energy_enabled(void)3825 static inline bool sched_energy_enabled(void)
3826 {
3827 	return static_branch_unlikely(&sched_energy_present);
3828 }
3829 
3830 #else /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL): */
3831 
3832 #define perf_domain_span(pd) NULL
3833 
sched_energy_enabled(void)3834 static inline bool sched_energy_enabled(void) { return false; }
3835 
3836 #endif /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
3837 
3838 #ifdef CONFIG_MEMBARRIER
3839 
3840 /*
3841  * The scheduler provides memory barriers required by membarrier between:
3842  * - prior user-space memory accesses and store to rq->membarrier_state,
3843  * - store to rq->membarrier_state and following user-space memory accesses.
3844  * In the same way it provides those guarantees around store to rq->curr.
3845  */
membarrier_switch_mm(struct rq * rq,struct mm_struct * prev_mm,struct mm_struct * next_mm)3846 static inline void membarrier_switch_mm(struct rq *rq,
3847 					struct mm_struct *prev_mm,
3848 					struct mm_struct *next_mm)
3849 {
3850 	int membarrier_state;
3851 
3852 	if (prev_mm == next_mm)
3853 		return;
3854 
3855 	membarrier_state = atomic_read(&next_mm->membarrier_state);
3856 	if (READ_ONCE(rq->membarrier_state) == membarrier_state)
3857 		return;
3858 
3859 	WRITE_ONCE(rq->membarrier_state, membarrier_state);
3860 }
3861 
3862 #else /* !CONFIG_MEMBARRIER: */
3863 
membarrier_switch_mm(struct rq * rq,struct mm_struct * prev_mm,struct mm_struct * next_mm)3864 static inline void membarrier_switch_mm(struct rq *rq,
3865 					struct mm_struct *prev_mm,
3866 					struct mm_struct *next_mm)
3867 {
3868 }
3869 
3870 #endif /* !CONFIG_MEMBARRIER */
3871 
is_per_cpu_kthread(struct task_struct * p)3872 static inline bool is_per_cpu_kthread(struct task_struct *p)
3873 {
3874 	if (!(p->flags & PF_KTHREAD))
3875 		return false;
3876 
3877 	if (p->nr_cpus_allowed != 1)
3878 		return false;
3879 
3880 	return true;
3881 }
3882 
3883 extern void swake_up_all_locked(struct swait_queue_head *q);
3884 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
3885 
3886 extern int try_to_wake_up(struct task_struct *tsk, unsigned int state, int wake_flags);
3887 
3888 #ifdef CONFIG_PREEMPT_DYNAMIC
3889 extern int preempt_dynamic_mode;
3890 extern int sched_dynamic_mode(const char *str);
3891 extern void sched_dynamic_update(int mode);
3892 #endif
3893 extern const char *preempt_modes[];
3894 
3895 #ifdef CONFIG_SCHED_MM_CID
3896 
cid_on_cpu(unsigned int cid)3897 static __always_inline bool cid_on_cpu(unsigned int cid)
3898 {
3899 	return cid & MM_CID_ONCPU;
3900 }
3901 
cid_in_transit(unsigned int cid)3902 static __always_inline bool cid_in_transit(unsigned int cid)
3903 {
3904 	return cid & MM_CID_TRANSIT;
3905 }
3906 
cpu_cid_to_cid(unsigned int cid)3907 static __always_inline unsigned int cpu_cid_to_cid(unsigned int cid)
3908 {
3909 	return cid & ~MM_CID_ONCPU;
3910 }
3911 
cid_to_cpu_cid(unsigned int cid)3912 static __always_inline unsigned int cid_to_cpu_cid(unsigned int cid)
3913 {
3914 	return cid | MM_CID_ONCPU;
3915 }
3916 
cid_to_transit_cid(unsigned int cid)3917 static __always_inline unsigned int cid_to_transit_cid(unsigned int cid)
3918 {
3919 	return cid | MM_CID_TRANSIT;
3920 }
3921 
cid_from_transit_cid(unsigned int cid)3922 static __always_inline unsigned int cid_from_transit_cid(unsigned int cid)
3923 {
3924 	return cid & ~MM_CID_TRANSIT;
3925 }
3926 
cid_on_task(unsigned int cid)3927 static __always_inline bool cid_on_task(unsigned int cid)
3928 {
3929 	/* True if none of the MM_CID_ONCPU, MM_CID_TRANSIT, MM_CID_UNSET bits is set */
3930 	return cid < MM_CID_TRANSIT;
3931 }
3932 
mm_drop_cid(struct mm_struct * mm,unsigned int cid)3933 static __always_inline void mm_drop_cid(struct mm_struct *mm, unsigned int cid)
3934 {
3935 	clear_bit(cid, mm_cidmask(mm));
3936 }
3937 
mm_unset_cid_on_task(struct task_struct * t)3938 static __always_inline void mm_unset_cid_on_task(struct task_struct *t)
3939 {
3940 	unsigned int cid = t->mm_cid.cid;
3941 
3942 	t->mm_cid.cid = MM_CID_UNSET;
3943 	if (cid_on_task(cid))
3944 		mm_drop_cid(t->mm, cid);
3945 }
3946 
mm_drop_cid_on_cpu(struct mm_struct * mm,struct mm_cid_pcpu * pcp)3947 static __always_inline void mm_drop_cid_on_cpu(struct mm_struct *mm, struct mm_cid_pcpu *pcp)
3948 {
3949 	/* Clear the ONCPU bit, but do not set UNSET in the per CPU storage */
3950 	if (cid_on_cpu(pcp->cid)) {
3951 		pcp->cid = cpu_cid_to_cid(pcp->cid);
3952 		mm_drop_cid(mm, pcp->cid);
3953 	}
3954 }
3955 
__mm_get_cid(struct mm_struct * mm,unsigned int max_cids)3956 static inline unsigned int __mm_get_cid(struct mm_struct *mm, unsigned int max_cids)
3957 {
3958 	unsigned int cid = find_first_zero_bit(mm_cidmask(mm), max_cids);
3959 
3960 	if (cid >= max_cids)
3961 		return MM_CID_UNSET;
3962 	if (test_and_set_bit(cid, mm_cidmask(mm)))
3963 		return MM_CID_UNSET;
3964 	return cid;
3965 }
3966 
mm_get_cid(struct mm_struct * mm)3967 static inline unsigned int mm_get_cid(struct mm_struct *mm)
3968 {
3969 	unsigned int cid = __mm_get_cid(mm, READ_ONCE(mm->mm_cid.max_cids));
3970 
3971 	while (cid == MM_CID_UNSET) {
3972 		cpu_relax();
3973 		cid = __mm_get_cid(mm, num_possible_cpus());
3974 	}
3975 	return cid;
3976 }
3977 
mm_cid_converge(struct mm_struct * mm,unsigned int orig_cid,unsigned int max_cids)3978 static inline unsigned int mm_cid_converge(struct mm_struct *mm, unsigned int orig_cid,
3979 					   unsigned int max_cids)
3980 {
3981 	unsigned int new_cid, cid = cpu_cid_to_cid(orig_cid);
3982 
3983 	/* Is it in the optimal CID space? */
3984 	if (likely(cid < max_cids))
3985 		return orig_cid;
3986 
3987 	/* Try to find one in the optimal space. Otherwise keep the provided. */
3988 	new_cid = __mm_get_cid(mm, max_cids);
3989 	if (new_cid != MM_CID_UNSET) {
3990 		mm_drop_cid(mm, cid);
3991 		/* Preserve the ONCPU mode of the original CID */
3992 		return new_cid | (orig_cid & MM_CID_ONCPU);
3993 	}
3994 	return orig_cid;
3995 }
3996 
mm_cid_update_task_cid(struct task_struct * t,unsigned int cid)3997 static __always_inline void mm_cid_update_task_cid(struct task_struct *t, unsigned int cid)
3998 {
3999 	if (t->mm_cid.cid != cid) {
4000 		t->mm_cid.cid = cid;
4001 		rseq_sched_set_ids_changed(t);
4002 	}
4003 }
4004 
mm_cid_update_pcpu_cid(struct mm_struct * mm,unsigned int cid)4005 static __always_inline void mm_cid_update_pcpu_cid(struct mm_struct *mm, unsigned int cid)
4006 {
4007 	__this_cpu_write(mm->mm_cid.pcpu->cid, cid);
4008 }
4009 
mm_cid_from_cpu(struct task_struct * t,unsigned int cpu_cid,unsigned int mode)4010 static __always_inline void mm_cid_from_cpu(struct task_struct *t, unsigned int cpu_cid,
4011 					    unsigned int mode)
4012 {
4013 	unsigned int max_cids, tcid = t->mm_cid.cid;
4014 	struct mm_struct *mm = t->mm;
4015 
4016 	max_cids = READ_ONCE(mm->mm_cid.max_cids);
4017 	/* Optimize for the common case where both have the ONCPU bit set */
4018 	if (likely(cid_on_cpu(cpu_cid & tcid))) {
4019 		if (likely(cpu_cid_to_cid(cpu_cid) < max_cids)) {
4020 			mm_cid_update_task_cid(t, cpu_cid);
4021 			return;
4022 		}
4023 		/* Try to converge into the optimal CID space */
4024 		cpu_cid = mm_cid_converge(mm, cpu_cid, max_cids);
4025 	} else {
4026 		/* Hand over or drop the task owned CID */
4027 		if (cid_on_task(tcid)) {
4028 			if (cid_on_cpu(cpu_cid))
4029 				mm_unset_cid_on_task(t);
4030 			else
4031 				cpu_cid = cid_to_cpu_cid(tcid);
4032 		}
4033 		/* Still nothing, allocate a new one */
4034 		if (!cid_on_cpu(cpu_cid))
4035 			cpu_cid = cid_to_cpu_cid(mm_get_cid(mm));
4036 
4037 		/* Handle the transition mode flag if required */
4038 		if (mode & MM_CID_TRANSIT)
4039 			cpu_cid = cpu_cid_to_cid(cpu_cid) | MM_CID_TRANSIT;
4040 	}
4041 	mm_cid_update_pcpu_cid(mm, cpu_cid);
4042 	mm_cid_update_task_cid(t, cpu_cid);
4043 }
4044 
mm_cid_from_task(struct task_struct * t,unsigned int cpu_cid,unsigned int mode)4045 static __always_inline void mm_cid_from_task(struct task_struct *t, unsigned int cpu_cid,
4046 					     unsigned int mode)
4047 {
4048 	unsigned int max_cids, tcid = t->mm_cid.cid;
4049 	struct mm_struct *mm = t->mm;
4050 
4051 	max_cids = READ_ONCE(mm->mm_cid.max_cids);
4052 	/* Optimize for the common case, where both have the ONCPU bit clear */
4053 	if (likely(cid_on_task(tcid | cpu_cid))) {
4054 		if (likely(tcid < max_cids)) {
4055 			mm_cid_update_pcpu_cid(mm, tcid);
4056 			return;
4057 		}
4058 		/* Try to converge into the optimal CID space */
4059 		tcid = mm_cid_converge(mm, tcid, max_cids);
4060 	} else {
4061 		/* Hand over or drop the CPU owned CID */
4062 		if (cid_on_cpu(cpu_cid)) {
4063 			if (cid_on_task(tcid))
4064 				mm_drop_cid_on_cpu(mm, this_cpu_ptr(mm->mm_cid.pcpu));
4065 			else
4066 				tcid = cpu_cid_to_cid(cpu_cid);
4067 		}
4068 		/* Still nothing, allocate a new one */
4069 		if (!cid_on_task(tcid))
4070 			tcid = mm_get_cid(mm);
4071 		/* Set the transition mode flag if required */
4072 		tcid |= mode & MM_CID_TRANSIT;
4073 	}
4074 	mm_cid_update_pcpu_cid(mm, tcid);
4075 	mm_cid_update_task_cid(t, tcid);
4076 }
4077 
mm_cid_schedin(struct task_struct * next)4078 static __always_inline void mm_cid_schedin(struct task_struct *next)
4079 {
4080 	struct mm_struct *mm = next->mm;
4081 	unsigned int cpu_cid, mode;
4082 
4083 	if (!next->mm_cid.active)
4084 		return;
4085 
4086 	cpu_cid = __this_cpu_read(mm->mm_cid.pcpu->cid);
4087 	mode = READ_ONCE(mm->mm_cid.mode);
4088 	if (likely(!cid_on_cpu(mode)))
4089 		mm_cid_from_task(next, cpu_cid, mode);
4090 	else
4091 		mm_cid_from_cpu(next, cpu_cid, mode);
4092 }
4093 
mm_cid_schedout(struct task_struct * prev)4094 static __always_inline void mm_cid_schedout(struct task_struct *prev)
4095 {
4096 	struct mm_struct *mm = prev->mm;
4097 	unsigned int mode, cid;
4098 
4099 	/* During mode transitions CIDs are temporary and need to be dropped */
4100 	if (likely(!cid_in_transit(prev->mm_cid.cid)))
4101 		return;
4102 
4103 	mode = READ_ONCE(mm->mm_cid.mode);
4104 	cid = cid_from_transit_cid(prev->mm_cid.cid);
4105 
4106 	/*
4107 	 * If transition mode is done, transfer ownership when the CID is
4108 	 * within the convergence range to optimize the next schedule in.
4109 	 */
4110 	if (!cid_in_transit(mode) && cid < READ_ONCE(mm->mm_cid.max_cids)) {
4111 		if (cid_on_cpu(mode))
4112 			cid = cid_to_cpu_cid(cid);
4113 
4114 		/* Update both so that the next schedule in goes into the fast path */
4115 		mm_cid_update_pcpu_cid(mm, cid);
4116 		prev->mm_cid.cid = cid;
4117 	} else {
4118 		mm_drop_cid(mm, cid);
4119 		prev->mm_cid.cid = MM_CID_UNSET;
4120 	}
4121 }
4122 
mm_cid_switch_to(struct task_struct * prev,struct task_struct * next)4123 static inline void mm_cid_switch_to(struct task_struct *prev, struct task_struct *next)
4124 {
4125 	mm_cid_schedout(prev);
4126 	mm_cid_schedin(next);
4127 }
4128 
4129 #else /* !CONFIG_SCHED_MM_CID: */
mm_cid_switch_to(struct task_struct * prev,struct task_struct * next)4130 static inline void mm_cid_switch_to(struct task_struct *prev, struct task_struct *next) { }
4131 #endif /* !CONFIG_SCHED_MM_CID */
4132 
4133 #ifdef CONFIG_SCHED_CACHE
4134 DECLARE_STATIC_KEY_FALSE(sched_cache_present);
4135 DECLARE_STATIC_KEY_FALSE(sched_cache_active);
4136 extern int sysctl_sched_cache_user;
4137 extern unsigned int llc_aggr_tolerance;
4138 extern unsigned int llc_epoch_period;
4139 extern unsigned int llc_epoch_affinity_timeout;
4140 extern unsigned int llc_imb_pct;
4141 extern unsigned int llc_overaggr_pct;
4142 
sched_cache_enabled(void)4143 static inline bool sched_cache_enabled(void)
4144 {
4145 	return static_branch_unlikely(&sched_cache_active);
4146 }
4147 
4148 extern void sched_cache_active_set(void);
4149 
4150 #endif
4151 
4152 void sched_domains_free_llc_id(int cpu);
4153 
4154 extern void init_sched_mm(struct task_struct *p);
4155 
4156 extern u64 avg_vruntime(struct cfs_rq *cfs_rq);
4157 extern int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se);
4158 static inline
move_queued_task_locked(struct rq * src_rq,struct rq * dst_rq,struct task_struct * task)4159 void move_queued_task_locked(struct rq *src_rq, struct rq *dst_rq, struct task_struct *task)
4160 {
4161 	lockdep_assert_rq_held(src_rq);
4162 	lockdep_assert_rq_held(dst_rq);
4163 
4164 	deactivate_task(src_rq, task, 0);
4165 	set_task_cpu(task, dst_rq->cpu);
4166 	activate_task(dst_rq, task, 0);
4167 	wakeup_preempt(dst_rq, task, 0);
4168 }
4169 
4170 static inline
task_is_pushable(struct rq * rq,struct task_struct * p,int cpu)4171 bool task_is_pushable(struct rq *rq, struct task_struct *p, int cpu)
4172 {
4173 	if (!task_on_cpu(rq, p) &&
4174 	    cpumask_test_cpu(cpu, &p->cpus_mask))
4175 		return true;
4176 
4177 	return false;
4178 }
4179 
4180 #ifdef CONFIG_RT_MUTEXES
4181 
__rt_effective_prio(struct task_struct * pi_task,int prio)4182 static inline int __rt_effective_prio(struct task_struct *pi_task, int prio)
4183 {
4184 	if (pi_task)
4185 		prio = min(prio, pi_task->prio);
4186 
4187 	return prio;
4188 }
4189 
rt_effective_prio(struct task_struct * p,int prio)4190 static inline int rt_effective_prio(struct task_struct *p, int prio)
4191 {
4192 	struct task_struct *pi_task = rt_mutex_get_top_task(p);
4193 
4194 	return __rt_effective_prio(pi_task, prio);
4195 }
4196 
4197 #else /* !CONFIG_RT_MUTEXES: */
4198 
rt_effective_prio(struct task_struct * p,int prio)4199 static inline int rt_effective_prio(struct task_struct *p, int prio)
4200 {
4201 	return prio;
4202 }
4203 
4204 #endif /* !CONFIG_RT_MUTEXES */
4205 
4206 extern int __sched_setscheduler(struct task_struct *p, const struct sched_attr *attr, bool user, bool pi);
4207 extern int __sched_setaffinity(struct task_struct *p, struct affinity_context *ctx);
4208 extern const struct sched_class *__setscheduler_class(int policy, int prio);
4209 extern void set_load_weight(struct task_struct *p, bool update_load);
4210 extern void enqueue_task(struct rq *rq, struct task_struct *p, int flags);
4211 extern bool dequeue_task(struct rq *rq, struct task_struct *p, int flags);
4212 
4213 extern struct balance_callback *splice_balance_callbacks(struct rq *rq);
4214 
4215 extern void __balance_callbacks(struct rq *rq, struct rq_flags *rf);
4216 extern void balance_callbacks(struct rq *rq, struct balance_callback *head);
4217 
4218 /*
4219  * The 'sched_change' pattern is the safe, easy and slow way of changing a
4220  * task's scheduling properties. It dequeues a task, such that the scheduler
4221  * is fully unaware of it; at which point its properties can be modified;
4222  * after which it is enqueued again.
4223  *
4224  * Typically this must be called while holding task_rq_lock, since most/all
4225  * properties are serialized under those locks. There is currently one
4226  * exception to this rule in sched/ext which only holds rq->lock.
4227  */
4228 
4229 /*
4230  * This structure is a temporary, used to preserve/convey the queueing state
4231  * of the task between sched_change_begin() and sched_change_end(). Ensuring
4232  * the task's queueing state is idempotent across the operation.
4233  */
4234 struct sched_change_ctx {
4235 	u64			prio;
4236 	struct task_struct	*p;
4237 	const struct sched_class *class;
4238 	int			flags;
4239 	bool			queued;
4240 	bool			running;
4241 };
4242 
4243 struct sched_change_ctx *sched_change_begin(struct task_struct *p, unsigned int flags);
4244 void sched_change_end(struct sched_change_ctx *ctx);
4245 
4246 DEFINE_CLASS(sched_change, struct sched_change_ctx *,
4247 	     sched_change_end(_T),
4248 	     sched_change_begin(p, flags),
4249 	     struct task_struct *p, unsigned int flags)
4250 
4251 DEFINE_CLASS_IS_UNCONDITIONAL(sched_change)
4252 
4253 #include "ext/ext.h"
4254 
4255 #endif /* _KERNEL_SCHED_SCHED_H */
4256