blob: fe755c1a0af95723dd132b09b16bc7751f514f03 [file] [log] [blame]
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00001/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Scheduler internal types and methods:
4 */
5#include <linux/sched.h>
6
7#include <linux/sched/autogroup.h>
8#include <linux/sched/clock.h>
9#include <linux/sched/coredump.h>
10#include <linux/sched/cpufreq.h>
11#include <linux/sched/cputime.h>
12#include <linux/sched/deadline.h>
13#include <linux/sched/debug.h>
14#include <linux/sched/hotplug.h>
15#include <linux/sched/idle.h>
16#include <linux/sched/init.h>
17#include <linux/sched/isolation.h>
18#include <linux/sched/jobctl.h>
19#include <linux/sched/loadavg.h>
20#include <linux/sched/mm.h>
21#include <linux/sched/nohz.h>
22#include <linux/sched/numa_balancing.h>
23#include <linux/sched/prio.h>
24#include <linux/sched/rt.h>
25#include <linux/sched/signal.h>
26#include <linux/sched/smt.h>
27#include <linux/sched/stat.h>
28#include <linux/sched/sysctl.h>
29#include <linux/sched/task.h>
30#include <linux/sched/task_stack.h>
31#include <linux/sched/topology.h>
32#include <linux/sched/user.h>
33#include <linux/sched/wake_q.h>
34#include <linux/sched/xacct.h>
35
36#include <uapi/linux/sched/types.h>
37
38#include <linux/binfmts.h>
39#include <linux/blkdev.h>
40#include <linux/compat.h>
41#include <linux/context_tracking.h>
42#include <linux/cpufreq.h>
43#include <linux/cpuidle.h>
44#include <linux/cpuset.h>
45#include <linux/ctype.h>
46#include <linux/debugfs.h>
47#include <linux/delayacct.h>
David Brazdil0f672f62019-12-10 10:32:29 +000048#include <linux/energy_model.h>
Andrew Scullb4b6d4a2019-01-02 15:54:55 +000049#include <linux/init_task.h>
50#include <linux/kprobes.h>
51#include <linux/kthread.h>
52#include <linux/membarrier.h>
53#include <linux/migrate.h>
54#include <linux/mmu_context.h>
55#include <linux/nmi.h>
56#include <linux/proc_fs.h>
57#include <linux/prefetch.h>
58#include <linux/profile.h>
David Brazdil0f672f62019-12-10 10:32:29 +000059#include <linux/psi.h>
Andrew Scullb4b6d4a2019-01-02 15:54:55 +000060#include <linux/rcupdate_wait.h>
61#include <linux/security.h>
Andrew Scullb4b6d4a2019-01-02 15:54:55 +000062#include <linux/stop_machine.h>
63#include <linux/suspend.h>
64#include <linux/swait.h>
65#include <linux/syscalls.h>
66#include <linux/task_work.h>
67#include <linux/tsacct_kern.h>
68
69#include <asm/tlb.h>
70
71#ifdef CONFIG_PARAVIRT
72# include <asm/paravirt.h>
73#endif
74
75#include "cpupri.h"
76#include "cpudeadline.h"
77
78#ifdef CONFIG_SCHED_DEBUG
79# define SCHED_WARN_ON(x) WARN_ONCE(x, #x)
80#else
81# define SCHED_WARN_ON(x) ({ (void)(x), 0; })
82#endif
83
84struct rq;
85struct cpuidle_state;
86
87/* task_struct::on_rq states: */
88#define TASK_ON_RQ_QUEUED 1
89#define TASK_ON_RQ_MIGRATING 2
90
91extern __read_mostly int scheduler_running;
92
93extern unsigned long calc_load_update;
94extern atomic_long_t calc_load_tasks;
95
96extern void calc_global_load_tick(struct rq *this_rq);
97extern long calc_load_fold_active(struct rq *this_rq, long adjust);
98
Andrew Scullb4b6d4a2019-01-02 15:54:55 +000099/*
100 * Helpers for converting nanosecond timing to jiffy resolution
101 */
102#define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
103
104/*
105 * Increase resolution of nice-level calculations for 64-bit architectures.
106 * The extra resolution improves shares distribution and load balancing of
107 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
108 * hierarchies, especially on larger systems. This is not a user-visible change
109 * and does not change the user-interface for setting shares/weights.
110 *
111 * We increase resolution only if we have enough bits to allow this increased
112 * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
113 * are pretty high and the returns do not justify the increased costs.
114 *
115 * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
116 * increase coverage and consistency always enable it on 64-bit platforms.
117 */
118#ifdef CONFIG_64BIT
119# define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
120# define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT)
Olivier Deprez0e641232021-09-23 10:07:05 +0200121# define scale_load_down(w) \
122({ \
123 unsigned long __w = (w); \
124 if (__w) \
125 __w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \
126 __w; \
127})
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000128#else
129# define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT)
130# define scale_load(w) (w)
131# define scale_load_down(w) (w)
132#endif
133
134/*
135 * Task weight (visible to users) and its load (invisible to users) have
136 * independent resolution, but they should be well calibrated. We use
137 * scale_load() and scale_load_down(w) to convert between them. The
138 * following must be true:
139 *
140 * scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD
141 *
142 */
143#define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT)
144
145/*
146 * Single value that decides SCHED_DEADLINE internal math precision.
147 * 10 -> just above 1us
148 * 9 -> just above 0.5us
149 */
150#define DL_SCALE 10
151
152/*
153 * Single value that denotes runtime == period, ie unlimited time.
154 */
155#define RUNTIME_INF ((u64)~0ULL)
156
157static inline int idle_policy(int policy)
158{
159 return policy == SCHED_IDLE;
160}
161static inline int fair_policy(int policy)
162{
163 return policy == SCHED_NORMAL || policy == SCHED_BATCH;
164}
165
166static inline int rt_policy(int policy)
167{
168 return policy == SCHED_FIFO || policy == SCHED_RR;
169}
170
171static inline int dl_policy(int policy)
172{
173 return policy == SCHED_DEADLINE;
174}
175static inline bool valid_policy(int policy)
176{
177 return idle_policy(policy) || fair_policy(policy) ||
178 rt_policy(policy) || dl_policy(policy);
179}
180
David Brazdil0f672f62019-12-10 10:32:29 +0000181static inline int task_has_idle_policy(struct task_struct *p)
182{
183 return idle_policy(p->policy);
184}
185
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000186static inline int task_has_rt_policy(struct task_struct *p)
187{
188 return rt_policy(p->policy);
189}
190
191static inline int task_has_dl_policy(struct task_struct *p)
192{
193 return dl_policy(p->policy);
194}
195
196#define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
197
198/*
199 * !! For sched_setattr_nocheck() (kernel) only !!
200 *
201 * This is actually gross. :(
202 *
203 * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
204 * tasks, but still be able to sleep. We need this on platforms that cannot
205 * atomically change clock frequency. Remove once fast switching will be
206 * available on such platforms.
207 *
208 * SUGOV stands for SchedUtil GOVernor.
209 */
210#define SCHED_FLAG_SUGOV 0x10000000
211
Olivier Deprez0e641232021-09-23 10:07:05 +0200212#define SCHED_DL_FLAGS (SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV)
213
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000214static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se)
215{
216#ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
217 return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
218#else
219 return false;
220#endif
221}
222
223/*
224 * Tells if entity @a should preempt entity @b.
225 */
226static inline bool
227dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
228{
229 return dl_entity_is_special(a) ||
230 dl_time_before(a->deadline, b->deadline);
231}
232
233/*
234 * This is the priority-queue data structure of the RT scheduling class:
235 */
236struct rt_prio_array {
237 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
238 struct list_head queue[MAX_RT_PRIO];
239};
240
241struct rt_bandwidth {
242 /* nests inside the rq lock: */
243 raw_spinlock_t rt_runtime_lock;
244 ktime_t rt_period;
245 u64 rt_runtime;
246 struct hrtimer rt_period_timer;
247 unsigned int rt_period_active;
248};
249
250void __dl_clear_params(struct task_struct *p);
251
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000252struct dl_bandwidth {
253 raw_spinlock_t dl_runtime_lock;
254 u64 dl_runtime;
255 u64 dl_period;
256};
257
258static inline int dl_bandwidth_enabled(void)
259{
260 return sysctl_sched_rt_runtime >= 0;
261}
262
Olivier Deprez0e641232021-09-23 10:07:05 +0200263/*
264 * To keep the bandwidth of -deadline tasks under control
265 * we need some place where:
266 * - store the maximum -deadline bandwidth of each cpu;
267 * - cache the fraction of bandwidth that is currently allocated in
268 * each root domain;
269 *
270 * This is all done in the data structure below. It is similar to the
271 * one used for RT-throttling (rt_bandwidth), with the main difference
272 * that, since here we are only interested in admission control, we
273 * do not decrease any runtime while the group "executes", neither we
274 * need a timer to replenish it.
275 *
276 * With respect to SMP, bandwidth is given on a per root domain basis,
277 * meaning that:
278 * - bw (< 100%) is the deadline bandwidth of each CPU;
279 * - total_bw is the currently allocated bandwidth in each root domain;
280 */
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000281struct dl_bw {
282 raw_spinlock_t lock;
283 u64 bw;
284 u64 total_bw;
285};
286
287static inline void __dl_update(struct dl_bw *dl_b, s64 bw);
288
289static inline
290void __dl_sub(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
291{
292 dl_b->total_bw -= tsk_bw;
293 __dl_update(dl_b, (s32)tsk_bw / cpus);
294}
295
296static inline
297void __dl_add(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
298{
299 dl_b->total_bw += tsk_bw;
300 __dl_update(dl_b, -((s32)tsk_bw / cpus));
301}
302
303static inline
304bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw)
305{
306 return dl_b->bw != -1 &&
307 dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw;
308}
309
310extern void dl_change_utilization(struct task_struct *p, u64 new_bw);
311extern void init_dl_bw(struct dl_bw *dl_b);
312extern int sched_dl_global_validate(void);
313extern void sched_dl_do_global(void);
314extern int sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
315extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
316extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
317extern bool __checkparam_dl(const struct sched_attr *attr);
318extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
319extern int dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
320extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
321extern bool dl_cpu_busy(unsigned int cpu);
322
323#ifdef CONFIG_CGROUP_SCHED
324
325#include <linux/cgroup.h>
David Brazdil0f672f62019-12-10 10:32:29 +0000326#include <linux/psi.h>
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000327
328struct cfs_rq;
329struct rt_rq;
330
331extern struct list_head task_groups;
332
333struct cfs_bandwidth {
334#ifdef CONFIG_CFS_BANDWIDTH
335 raw_spinlock_t lock;
336 ktime_t period;
337 u64 quota;
338 u64 runtime;
339 s64 hierarchical_quota;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000340
David Brazdil0f672f62019-12-10 10:32:29 +0000341 u8 idle;
342 u8 period_active;
343 u8 distribute_running;
344 u8 slack_started;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000345 struct hrtimer period_timer;
346 struct hrtimer slack_timer;
347 struct list_head throttled_cfs_rq;
348
349 /* Statistics: */
350 int nr_periods;
351 int nr_throttled;
352 u64 throttled_time;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000353#endif
354};
355
356/* Task group related information */
357struct task_group {
358 struct cgroup_subsys_state css;
359
360#ifdef CONFIG_FAIR_GROUP_SCHED
361 /* schedulable entities of this group on each CPU */
362 struct sched_entity **se;
363 /* runqueue "owned" by this group on each CPU */
364 struct cfs_rq **cfs_rq;
365 unsigned long shares;
366
367#ifdef CONFIG_SMP
368 /*
369 * load_avg can be heavily contended at clock tick time, so put
370 * it in its own cacheline separated from the fields above which
371 * will also be accessed at each tick.
372 */
373 atomic_long_t load_avg ____cacheline_aligned;
374#endif
375#endif
376
377#ifdef CONFIG_RT_GROUP_SCHED
378 struct sched_rt_entity **rt_se;
379 struct rt_rq **rt_rq;
380
381 struct rt_bandwidth rt_bandwidth;
382#endif
383
384 struct rcu_head rcu;
385 struct list_head list;
386
387 struct task_group *parent;
388 struct list_head siblings;
389 struct list_head children;
390
391#ifdef CONFIG_SCHED_AUTOGROUP
392 struct autogroup *autogroup;
393#endif
394
395 struct cfs_bandwidth cfs_bandwidth;
David Brazdil0f672f62019-12-10 10:32:29 +0000396
397#ifdef CONFIG_UCLAMP_TASK_GROUP
398 /* The two decimal precision [%] value requested from user-space */
399 unsigned int uclamp_pct[UCLAMP_CNT];
400 /* Clamp values requested for a task group */
401 struct uclamp_se uclamp_req[UCLAMP_CNT];
402 /* Effective clamp values used for a task group */
403 struct uclamp_se uclamp[UCLAMP_CNT];
404#endif
405
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000406};
407
408#ifdef CONFIG_FAIR_GROUP_SCHED
409#define ROOT_TASK_GROUP_LOAD NICE_0_LOAD
410
411/*
412 * A weight of 0 or 1 can cause arithmetics problems.
413 * A weight of a cfs_rq is the sum of weights of which entities
414 * are queued on this cfs_rq, so a weight of a entity should not be
415 * too large, so as the shares value of a task group.
416 * (The default weight is 1024 - so there's no practical
417 * limitation from this.)
418 */
419#define MIN_SHARES (1UL << 1)
420#define MAX_SHARES (1UL << 18)
421#endif
422
423typedef int (*tg_visitor)(struct task_group *, void *);
424
425extern int walk_tg_tree_from(struct task_group *from,
426 tg_visitor down, tg_visitor up, void *data);
427
428/*
429 * Iterate the full tree, calling @down when first entering a node and @up when
430 * leaving it for the final time.
431 *
432 * Caller must hold rcu_lock or sufficient equivalent.
433 */
434static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
435{
436 return walk_tg_tree_from(&root_task_group, down, up, data);
437}
438
439extern int tg_nop(struct task_group *tg, void *data);
440
441extern void free_fair_sched_group(struct task_group *tg);
442extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
443extern void online_fair_sched_group(struct task_group *tg);
444extern void unregister_fair_sched_group(struct task_group *tg);
445extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
446 struct sched_entity *se, int cpu,
447 struct sched_entity *parent);
448extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
449
450extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
451extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
452extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
453
454extern void free_rt_sched_group(struct task_group *tg);
455extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
456extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
457 struct sched_rt_entity *rt_se, int cpu,
458 struct sched_rt_entity *parent);
459extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
460extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
461extern long sched_group_rt_runtime(struct task_group *tg);
462extern long sched_group_rt_period(struct task_group *tg);
463extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
464
465extern struct task_group *sched_create_group(struct task_group *parent);
466extern void sched_online_group(struct task_group *tg,
467 struct task_group *parent);
468extern void sched_destroy_group(struct task_group *tg);
469extern void sched_offline_group(struct task_group *tg);
470
471extern void sched_move_task(struct task_struct *tsk);
472
473#ifdef CONFIG_FAIR_GROUP_SCHED
474extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
475
476#ifdef CONFIG_SMP
477extern void set_task_rq_fair(struct sched_entity *se,
478 struct cfs_rq *prev, struct cfs_rq *next);
479#else /* !CONFIG_SMP */
480static inline void set_task_rq_fair(struct sched_entity *se,
481 struct cfs_rq *prev, struct cfs_rq *next) { }
482#endif /* CONFIG_SMP */
483#endif /* CONFIG_FAIR_GROUP_SCHED */
484
485#else /* CONFIG_CGROUP_SCHED */
486
487struct cfs_bandwidth { };
488
489#endif /* CONFIG_CGROUP_SCHED */
490
491/* CFS-related fields in a runqueue */
492struct cfs_rq {
493 struct load_weight load;
494 unsigned long runnable_weight;
495 unsigned int nr_running;
David Brazdil0f672f62019-12-10 10:32:29 +0000496 unsigned int h_nr_running; /* SCHED_{NORMAL,BATCH,IDLE} */
497 unsigned int idle_h_nr_running; /* SCHED_IDLE */
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000498
499 u64 exec_clock;
500 u64 min_vruntime;
501#ifndef CONFIG_64BIT
502 u64 min_vruntime_copy;
503#endif
504
505 struct rb_root_cached tasks_timeline;
506
507 /*
508 * 'curr' points to currently running entity on this cfs_rq.
509 * It is set to NULL otherwise (i.e when none are currently running).
510 */
511 struct sched_entity *curr;
512 struct sched_entity *next;
513 struct sched_entity *last;
514 struct sched_entity *skip;
515
516#ifdef CONFIG_SCHED_DEBUG
517 unsigned int nr_spread_over;
518#endif
519
520#ifdef CONFIG_SMP
521 /*
522 * CFS load tracking
523 */
524 struct sched_avg avg;
525#ifndef CONFIG_64BIT
526 u64 load_last_update_time_copy;
527#endif
528 struct {
529 raw_spinlock_t lock ____cacheline_aligned;
530 int nr;
531 unsigned long load_avg;
532 unsigned long util_avg;
533 unsigned long runnable_sum;
534 } removed;
535
536#ifdef CONFIG_FAIR_GROUP_SCHED
537 unsigned long tg_load_avg_contrib;
538 long propagate;
539 long prop_runnable_sum;
540
541 /*
542 * h_load = weight * f(tg)
543 *
544 * Where f(tg) is the recursive weight fraction assigned to
545 * this group.
546 */
547 unsigned long h_load;
548 u64 last_h_load_update;
549 struct sched_entity *h_load_next;
550#endif /* CONFIG_FAIR_GROUP_SCHED */
551#endif /* CONFIG_SMP */
552
553#ifdef CONFIG_FAIR_GROUP_SCHED
554 struct rq *rq; /* CPU runqueue to which this cfs_rq is attached */
555
556 /*
557 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
558 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
559 * (like users, containers etc.)
560 *
561 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
562 * This list is used during load balance.
563 */
564 int on_list;
565 struct list_head leaf_cfs_rq_list;
566 struct task_group *tg; /* group that "owns" this runqueue */
567
568#ifdef CONFIG_CFS_BANDWIDTH
569 int runtime_enabled;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000570 s64 runtime_remaining;
571
572 u64 throttled_clock;
573 u64 throttled_clock_task;
574 u64 throttled_clock_task_time;
575 int throttled;
576 int throttle_count;
577 struct list_head throttled_list;
578#endif /* CONFIG_CFS_BANDWIDTH */
579#endif /* CONFIG_FAIR_GROUP_SCHED */
580};
581
582static inline int rt_bandwidth_enabled(void)
583{
584 return sysctl_sched_rt_runtime >= 0;
585}
586
587/* RT IPI pull logic requires IRQ_WORK */
588#if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
589# define HAVE_RT_PUSH_IPI
590#endif
591
592/* Real-Time classes' related field in a runqueue: */
593struct rt_rq {
594 struct rt_prio_array active;
595 unsigned int rt_nr_running;
596 unsigned int rr_nr_running;
597#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
598 struct {
599 int curr; /* highest queued rt task prio */
600#ifdef CONFIG_SMP
601 int next; /* next highest */
602#endif
603 } highest_prio;
604#endif
605#ifdef CONFIG_SMP
606 unsigned long rt_nr_migratory;
607 unsigned long rt_nr_total;
608 int overloaded;
609 struct plist_head pushable_tasks;
610
611#endif /* CONFIG_SMP */
612 int rt_queued;
613
614 int rt_throttled;
615 u64 rt_time;
616 u64 rt_runtime;
617 /* Nests inside the rq lock: */
618 raw_spinlock_t rt_runtime_lock;
619
620#ifdef CONFIG_RT_GROUP_SCHED
621 unsigned long rt_nr_boosted;
622
623 struct rq *rq;
624 struct task_group *tg;
625#endif
626};
627
628static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
629{
630 return rt_rq->rt_queued && rt_rq->rt_nr_running;
631}
632
633/* Deadline class' related fields in a runqueue */
634struct dl_rq {
635 /* runqueue is an rbtree, ordered by deadline */
636 struct rb_root_cached root;
637
638 unsigned long dl_nr_running;
639
640#ifdef CONFIG_SMP
641 /*
642 * Deadline values of the currently executing and the
643 * earliest ready task on this rq. Caching these facilitates
David Brazdil0f672f62019-12-10 10:32:29 +0000644 * the decision whether or not a ready but not running task
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000645 * should migrate somewhere else.
646 */
647 struct {
648 u64 curr;
649 u64 next;
650 } earliest_dl;
651
652 unsigned long dl_nr_migratory;
653 int overloaded;
654
655 /*
656 * Tasks on this rq that can be pushed away. They are kept in
657 * an rb-tree, ordered by tasks' deadlines, with caching
658 * of the leftmost (earliest deadline) element.
659 */
660 struct rb_root_cached pushable_dl_tasks_root;
661#else
662 struct dl_bw dl_bw;
663#endif
664 /*
665 * "Active utilization" for this runqueue: increased when a
666 * task wakes up (becomes TASK_RUNNING) and decreased when a
667 * task blocks
668 */
669 u64 running_bw;
670
671 /*
672 * Utilization of the tasks "assigned" to this runqueue (including
673 * the tasks that are in runqueue and the tasks that executed on this
674 * CPU and blocked). Increased when a task moves to this runqueue, and
675 * decreased when the task moves away (migrates, changes scheduling
676 * policy, or terminates).
677 * This is needed to compute the "inactive utilization" for the
678 * runqueue (inactive utilization = this_bw - running_bw).
679 */
680 u64 this_bw;
681 u64 extra_bw;
682
683 /*
684 * Inverse of the fraction of CPU utilization that can be reclaimed
685 * by the GRUB algorithm.
686 */
687 u64 bw_ratio;
688};
689
690#ifdef CONFIG_FAIR_GROUP_SCHED
691/* An entity is a task if it doesn't "own" a runqueue */
692#define entity_is_task(se) (!se->my_q)
693#else
694#define entity_is_task(se) 1
695#endif
696
697#ifdef CONFIG_SMP
698/*
699 * XXX we want to get rid of these helpers and use the full load resolution.
700 */
701static inline long se_weight(struct sched_entity *se)
702{
703 return scale_load_down(se->load.weight);
704}
705
706static inline long se_runnable(struct sched_entity *se)
707{
708 return scale_load_down(se->runnable_weight);
709}
710
711static inline bool sched_asym_prefer(int a, int b)
712{
713 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
714}
715
David Brazdil0f672f62019-12-10 10:32:29 +0000716struct perf_domain {
717 struct em_perf_domain *em_pd;
718 struct perf_domain *next;
719 struct rcu_head rcu;
720};
721
722/* Scheduling group status flags */
723#define SG_OVERLOAD 0x1 /* More than one runnable task on a CPU. */
724#define SG_OVERUTILIZED 0x2 /* One or more CPUs are over-utilized. */
725
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000726/*
727 * We add the notion of a root-domain which will be used to define per-domain
728 * variables. Each exclusive cpuset essentially defines an island domain by
729 * fully partitioning the member CPUs from any other cpuset. Whenever a new
730 * exclusive cpuset is created, we also create and attach a new root-domain
731 * object.
732 *
733 */
734struct root_domain {
735 atomic_t refcount;
736 atomic_t rto_count;
737 struct rcu_head rcu;
738 cpumask_var_t span;
739 cpumask_var_t online;
740
David Brazdil0f672f62019-12-10 10:32:29 +0000741 /*
742 * Indicate pullable load on at least one CPU, e.g:
743 * - More than one runnable task
744 * - Running task is misfit
745 */
746 int overload;
747
748 /* Indicate one or more cpus over-utilized (tipping point) */
749 int overutilized;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000750
751 /*
752 * The bit corresponding to a CPU gets set here if such CPU has more
753 * than one runnable -deadline task (as it is below for RT tasks).
754 */
755 cpumask_var_t dlo_mask;
756 atomic_t dlo_count;
757 struct dl_bw dl_bw;
758 struct cpudl cpudl;
759
760#ifdef HAVE_RT_PUSH_IPI
761 /*
762 * For IPI pull requests, loop across the rto_mask.
763 */
764 struct irq_work rto_push_work;
765 raw_spinlock_t rto_lock;
766 /* These are only updated and read within rto_lock */
767 int rto_loop;
768 int rto_cpu;
769 /* These atomics are updated outside of a lock */
770 atomic_t rto_loop_next;
771 atomic_t rto_loop_start;
772#endif
773 /*
774 * The "RT overload" flag: it gets set if a CPU has more than
775 * one runnable RT task.
776 */
777 cpumask_var_t rto_mask;
778 struct cpupri cpupri;
779
780 unsigned long max_cpu_capacity;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000781
David Brazdil0f672f62019-12-10 10:32:29 +0000782 /*
783 * NULL-terminated list of performance domains intersecting with the
784 * CPUs of the rd. Protected by RCU.
785 */
786 struct perf_domain __rcu *pd;
787};
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000788
789extern void init_defrootdomain(void);
790extern int sched_init_domains(const struct cpumask *cpu_map);
791extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
792extern void sched_get_rd(struct root_domain *rd);
793extern void sched_put_rd(struct root_domain *rd);
794
795#ifdef HAVE_RT_PUSH_IPI
796extern void rto_push_irq_work_func(struct irq_work *work);
797#endif
798#endif /* CONFIG_SMP */
799
David Brazdil0f672f62019-12-10 10:32:29 +0000800#ifdef CONFIG_UCLAMP_TASK
801/*
802 * struct uclamp_bucket - Utilization clamp bucket
803 * @value: utilization clamp value for tasks on this clamp bucket
804 * @tasks: number of RUNNABLE tasks on this clamp bucket
805 *
806 * Keep track of how many tasks are RUNNABLE for a given utilization
807 * clamp value.
808 */
809struct uclamp_bucket {
810 unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
811 unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
812};
813
814/*
815 * struct uclamp_rq - rq's utilization clamp
816 * @value: currently active clamp values for a rq
817 * @bucket: utilization clamp buckets affecting a rq
818 *
819 * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
820 * A clamp value is affecting a rq when there is at least one task RUNNABLE
821 * (or actually running) with that value.
822 *
823 * There are up to UCLAMP_CNT possible different clamp values, currently there
824 * are only two: minimum utilization and maximum utilization.
825 *
826 * All utilization clamping values are MAX aggregated, since:
827 * - for util_min: we want to run the CPU at least at the max of the minimum
828 * utilization required by its currently RUNNABLE tasks.
829 * - for util_max: we want to allow the CPU to run up to the max of the
830 * maximum utilization allowed by its currently RUNNABLE tasks.
831 *
832 * Since on each system we expect only a limited number of different
833 * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
834 * the metrics required to compute all the per-rq utilization clamp values.
835 */
836struct uclamp_rq {
837 unsigned int value;
838 struct uclamp_bucket bucket[UCLAMP_BUCKETS];
839};
Olivier Deprez0e641232021-09-23 10:07:05 +0200840
841DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
David Brazdil0f672f62019-12-10 10:32:29 +0000842#endif /* CONFIG_UCLAMP_TASK */
843
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000844/*
845 * This is the main, per-CPU runqueue data structure.
846 *
847 * Locking rule: those places that want to lock multiple runqueues
848 * (such as the load balancing or the thread migration code), lock
849 * acquire operations must be ordered by ascending &runqueue.
850 */
851struct rq {
852 /* runqueue lock: */
853 raw_spinlock_t lock;
854
855 /*
856 * nr_running and cpu_load should be in the same cacheline because
857 * remote CPUs use both these fields when doing load calculation.
858 */
859 unsigned int nr_running;
860#ifdef CONFIG_NUMA_BALANCING
861 unsigned int nr_numa_running;
862 unsigned int nr_preferred_running;
863 unsigned int numa_migrate_on;
864#endif
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000865#ifdef CONFIG_NO_HZ_COMMON
866#ifdef CONFIG_SMP
867 unsigned long last_load_update_tick;
868 unsigned long last_blocked_load_update_tick;
869 unsigned int has_blocked_load;
870#endif /* CONFIG_SMP */
871 unsigned int nohz_tick_stopped;
872 atomic_t nohz_flags;
873#endif /* CONFIG_NO_HZ_COMMON */
874
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000875 unsigned long nr_load_updates;
876 u64 nr_switches;
877
David Brazdil0f672f62019-12-10 10:32:29 +0000878#ifdef CONFIG_UCLAMP_TASK
879 /* Utilization clamp values based on CPU's RUNNABLE tasks */
880 struct uclamp_rq uclamp[UCLAMP_CNT] ____cacheline_aligned;
881 unsigned int uclamp_flags;
882#define UCLAMP_FLAG_IDLE 0x01
883#endif
884
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000885 struct cfs_rq cfs;
886 struct rt_rq rt;
887 struct dl_rq dl;
888
889#ifdef CONFIG_FAIR_GROUP_SCHED
890 /* list of leaf cfs_rq on this CPU: */
891 struct list_head leaf_cfs_rq_list;
892 struct list_head *tmp_alone_branch;
893#endif /* CONFIG_FAIR_GROUP_SCHED */
894
895 /*
896 * This is part of a global counter where only the total sum
897 * over all CPUs matters. A task can increase this counter on
898 * one CPU and if it got migrated afterwards it may decrease
899 * it on another CPU. Always updated under the runqueue lock:
900 */
901 unsigned long nr_uninterruptible;
902
903 struct task_struct *curr;
904 struct task_struct *idle;
905 struct task_struct *stop;
906 unsigned long next_balance;
907 struct mm_struct *prev_mm;
908
909 unsigned int clock_update_flags;
910 u64 clock;
David Brazdil0f672f62019-12-10 10:32:29 +0000911 /* Ensure that all clocks are in the same cache line */
912 u64 clock_task ____cacheline_aligned;
913 u64 clock_pelt;
914 unsigned long lost_idle_time;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000915
916 atomic_t nr_iowait;
917
David Brazdil0f672f62019-12-10 10:32:29 +0000918#ifdef CONFIG_MEMBARRIER
919 int membarrier_state;
920#endif
921
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000922#ifdef CONFIG_SMP
David Brazdil0f672f62019-12-10 10:32:29 +0000923 struct root_domain *rd;
924 struct sched_domain __rcu *sd;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000925
926 unsigned long cpu_capacity;
927 unsigned long cpu_capacity_orig;
928
929 struct callback_head *balance_callback;
930
931 unsigned char idle_balance;
932
David Brazdil0f672f62019-12-10 10:32:29 +0000933 unsigned long misfit_task_load;
934
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000935 /* For active balancing */
936 int active_balance;
937 int push_cpu;
938 struct cpu_stop_work active_balance_work;
939
940 /* CPU of this runqueue: */
941 int cpu;
942 int online;
943
944 struct list_head cfs_tasks;
945
946 struct sched_avg avg_rt;
947 struct sched_avg avg_dl;
948#ifdef CONFIG_HAVE_SCHED_AVG_IRQ
949 struct sched_avg avg_irq;
950#endif
951 u64 idle_stamp;
952 u64 avg_idle;
953
954 /* This is used to determine avg_idle's max value */
955 u64 max_idle_balance_cost;
956#endif
957
958#ifdef CONFIG_IRQ_TIME_ACCOUNTING
959 u64 prev_irq_time;
960#endif
961#ifdef CONFIG_PARAVIRT
962 u64 prev_steal_time;
963#endif
964#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
965 u64 prev_steal_time_rq;
966#endif
967
968 /* calc_load related fields */
969 unsigned long calc_load_update;
970 long calc_load_active;
971
972#ifdef CONFIG_SCHED_HRTICK
973#ifdef CONFIG_SMP
974 int hrtick_csd_pending;
975 call_single_data_t hrtick_csd;
976#endif
977 struct hrtimer hrtick_timer;
Olivier Deprez0e641232021-09-23 10:07:05 +0200978 ktime_t hrtick_time;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000979#endif
980
981#ifdef CONFIG_SCHEDSTATS
982 /* latency stats */
983 struct sched_info rq_sched_info;
984 unsigned long long rq_cpu_time;
985 /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
986
987 /* sys_sched_yield() stats */
988 unsigned int yld_count;
989
990 /* schedule() stats */
991 unsigned int sched_count;
992 unsigned int sched_goidle;
993
994 /* try_to_wake_up() stats */
995 unsigned int ttwu_count;
996 unsigned int ttwu_local;
997#endif
998
999#ifdef CONFIG_SMP
1000 struct llist_head wake_list;
1001#endif
1002
1003#ifdef CONFIG_CPU_IDLE
1004 /* Must be inspected within a rcu lock section */
1005 struct cpuidle_state *idle_state;
1006#endif
1007};
1008
David Brazdil0f672f62019-12-10 10:32:29 +00001009#ifdef CONFIG_FAIR_GROUP_SCHED
1010
1011/* CPU runqueue to which this cfs_rq is attached */
1012static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1013{
1014 return cfs_rq->rq;
1015}
1016
1017#else
1018
1019static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1020{
1021 return container_of(cfs_rq, struct rq, cfs);
1022}
1023#endif
1024
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00001025static inline int cpu_of(struct rq *rq)
1026{
1027#ifdef CONFIG_SMP
1028 return rq->cpu;
1029#else
1030 return 0;
1031#endif
1032}
1033
1034
1035#ifdef CONFIG_SCHED_SMT
1036extern void __update_idle_core(struct rq *rq);
1037
1038static inline void update_idle_core(struct rq *rq)
1039{
1040 if (static_branch_unlikely(&sched_smt_present))
1041 __update_idle_core(rq);
1042}
1043
1044#else
1045static inline void update_idle_core(struct rq *rq) { }
1046#endif
1047
1048DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1049
1050#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
1051#define this_rq() this_cpu_ptr(&runqueues)
1052#define task_rq(p) cpu_rq(task_cpu(p))
1053#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
1054#define raw_rq() raw_cpu_ptr(&runqueues)
1055
David Brazdil0f672f62019-12-10 10:32:29 +00001056extern void update_rq_clock(struct rq *rq);
1057
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00001058static inline u64 __rq_clock_broken(struct rq *rq)
1059{
1060 return READ_ONCE(rq->clock);
1061}
1062
1063/*
1064 * rq::clock_update_flags bits
1065 *
1066 * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1067 * call to __schedule(). This is an optimisation to avoid
1068 * neighbouring rq clock updates.
1069 *
1070 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1071 * in effect and calls to update_rq_clock() are being ignored.
1072 *
1073 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1074 * made to update_rq_clock() since the last time rq::lock was pinned.
1075 *
1076 * If inside of __schedule(), clock_update_flags will have been
1077 * shifted left (a left shift is a cheap operation for the fast path
1078 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1079 *
1080 * if (rq-clock_update_flags >= RQCF_UPDATED)
1081 *
1082 * to check if %RQCF_UPADTED is set. It'll never be shifted more than
1083 * one position though, because the next rq_unpin_lock() will shift it
1084 * back.
1085 */
1086#define RQCF_REQ_SKIP 0x01
1087#define RQCF_ACT_SKIP 0x02
1088#define RQCF_UPDATED 0x04
1089
1090static inline void assert_clock_updated(struct rq *rq)
1091{
1092 /*
1093 * The only reason for not seeing a clock update since the
1094 * last rq_pin_lock() is if we're currently skipping updates.
1095 */
1096 SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
1097}
1098
1099static inline u64 rq_clock(struct rq *rq)
1100{
1101 lockdep_assert_held(&rq->lock);
1102 assert_clock_updated(rq);
1103
1104 return rq->clock;
1105}
1106
1107static inline u64 rq_clock_task(struct rq *rq)
1108{
1109 lockdep_assert_held(&rq->lock);
1110 assert_clock_updated(rq);
1111
1112 return rq->clock_task;
1113}
1114
1115static inline void rq_clock_skip_update(struct rq *rq)
1116{
1117 lockdep_assert_held(&rq->lock);
1118 rq->clock_update_flags |= RQCF_REQ_SKIP;
1119}
1120
1121/*
1122 * See rt task throttling, which is the only time a skip
1123 * request is cancelled.
1124 */
1125static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1126{
1127 lockdep_assert_held(&rq->lock);
1128 rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1129}
1130
1131struct rq_flags {
1132 unsigned long flags;
1133 struct pin_cookie cookie;
1134#ifdef CONFIG_SCHED_DEBUG
1135 /*
1136 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1137 * current pin context is stashed here in case it needs to be
1138 * restored in rq_repin_lock().
1139 */
1140 unsigned int clock_update_flags;
1141#endif
1142};
1143
1144static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1145{
1146 rf->cookie = lockdep_pin_lock(&rq->lock);
1147
1148#ifdef CONFIG_SCHED_DEBUG
1149 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1150 rf->clock_update_flags = 0;
1151#endif
1152}
1153
1154static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1155{
1156#ifdef CONFIG_SCHED_DEBUG
1157 if (rq->clock_update_flags > RQCF_ACT_SKIP)
1158 rf->clock_update_flags = RQCF_UPDATED;
1159#endif
1160
1161 lockdep_unpin_lock(&rq->lock, rf->cookie);
1162}
1163
1164static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1165{
1166 lockdep_repin_lock(&rq->lock, rf->cookie);
1167
1168#ifdef CONFIG_SCHED_DEBUG
1169 /*
1170 * Restore the value we stashed in @rf for this pin context.
1171 */
1172 rq->clock_update_flags |= rf->clock_update_flags;
1173#endif
1174}
1175
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00001176struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1177 __acquires(rq->lock);
1178
1179struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1180 __acquires(p->pi_lock)
1181 __acquires(rq->lock);
1182
1183static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1184 __releases(rq->lock)
1185{
1186 rq_unpin_lock(rq, rf);
1187 raw_spin_unlock(&rq->lock);
1188}
1189
1190static inline void
1191task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1192 __releases(rq->lock)
1193 __releases(p->pi_lock)
1194{
1195 rq_unpin_lock(rq, rf);
1196 raw_spin_unlock(&rq->lock);
1197 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1198}
1199
1200static inline void
1201rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1202 __acquires(rq->lock)
1203{
1204 raw_spin_lock_irqsave(&rq->lock, rf->flags);
1205 rq_pin_lock(rq, rf);
1206}
1207
1208static inline void
1209rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1210 __acquires(rq->lock)
1211{
1212 raw_spin_lock_irq(&rq->lock);
1213 rq_pin_lock(rq, rf);
1214}
1215
1216static inline void
1217rq_lock(struct rq *rq, struct rq_flags *rf)
1218 __acquires(rq->lock)
1219{
1220 raw_spin_lock(&rq->lock);
1221 rq_pin_lock(rq, rf);
1222}
1223
1224static inline void
1225rq_relock(struct rq *rq, struct rq_flags *rf)
1226 __acquires(rq->lock)
1227{
1228 raw_spin_lock(&rq->lock);
1229 rq_repin_lock(rq, rf);
1230}
1231
1232static inline void
1233rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1234 __releases(rq->lock)
1235{
1236 rq_unpin_lock(rq, rf);
1237 raw_spin_unlock_irqrestore(&rq->lock, rf->flags);
1238}
1239
1240static inline void
1241rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1242 __releases(rq->lock)
1243{
1244 rq_unpin_lock(rq, rf);
1245 raw_spin_unlock_irq(&rq->lock);
1246}
1247
1248static inline void
1249rq_unlock(struct rq *rq, struct rq_flags *rf)
1250 __releases(rq->lock)
1251{
1252 rq_unpin_lock(rq, rf);
1253 raw_spin_unlock(&rq->lock);
1254}
1255
David Brazdil0f672f62019-12-10 10:32:29 +00001256static inline struct rq *
1257this_rq_lock_irq(struct rq_flags *rf)
1258 __acquires(rq->lock)
1259{
1260 struct rq *rq;
1261
1262 local_irq_disable();
1263 rq = this_rq();
1264 rq_lock(rq, rf);
1265 return rq;
1266}
1267
1268#ifdef CONFIG_NUMA
1269enum numa_topology_type {
1270 NUMA_DIRECT,
1271 NUMA_GLUELESS_MESH,
1272 NUMA_BACKPLANE,
1273};
1274extern enum numa_topology_type sched_numa_topology_type;
1275extern int sched_max_numa_distance;
1276extern bool find_numa_distance(int distance);
1277extern void sched_init_numa(void);
1278extern void sched_domains_numa_masks_set(unsigned int cpu);
1279extern void sched_domains_numa_masks_clear(unsigned int cpu);
1280extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1281#else
1282static inline void sched_init_numa(void) { }
1283static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
1284static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1285static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1286{
1287 return nr_cpu_ids;
1288}
1289#endif
1290
1291#ifdef CONFIG_NUMA_BALANCING
1292/* The regions in numa_faults array from task_struct */
1293enum numa_faults_stats {
1294 NUMA_MEM = 0,
1295 NUMA_CPU,
1296 NUMA_MEMBUF,
1297 NUMA_CPUBUF
1298};
1299extern void sched_setnuma(struct task_struct *p, int node);
1300extern int migrate_task_to(struct task_struct *p, int cpu);
1301extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1302 int cpu, int scpu);
1303extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1304#else
1305static inline void
1306init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1307{
1308}
1309#endif /* CONFIG_NUMA_BALANCING */
1310
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00001311#ifdef CONFIG_SMP
David Brazdil0f672f62019-12-10 10:32:29 +00001312
1313static inline void
1314queue_balance_callback(struct rq *rq,
1315 struct callback_head *head,
1316 void (*func)(struct rq *rq))
1317{
1318 lockdep_assert_held(&rq->lock);
1319
1320 if (unlikely(head->next))
1321 return;
1322
1323 head->func = (void (*)(struct callback_head *))func;
1324 head->next = rq->balance_callback;
1325 rq->balance_callback = head;
1326}
1327
1328extern void sched_ttwu_pending(void);
1329
1330#define rcu_dereference_check_sched_domain(p) \
1331 rcu_dereference_check((p), \
1332 lockdep_is_held(&sched_domains_mutex))
1333
1334/*
1335 * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1336 * See destroy_sched_domains: call_rcu for details.
1337 *
1338 * The domain tree of any CPU may only be accessed from within
1339 * preempt-disabled sections.
1340 */
1341#define for_each_domain(cpu, __sd) \
1342 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1343 __sd; __sd = __sd->parent)
1344
1345#define for_each_lower_domain(sd) for (; sd; sd = sd->child)
1346
1347/**
1348 * highest_flag_domain - Return highest sched_domain containing flag.
1349 * @cpu: The CPU whose highest level of sched domain is to
1350 * be returned.
1351 * @flag: The flag to check for the highest sched_domain
1352 * for the given CPU.
1353 *
1354 * Returns the highest sched_domain of a CPU which contains the given flag.
1355 */
1356static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1357{
1358 struct sched_domain *sd, *hsd = NULL;
1359
1360 for_each_domain(cpu, sd) {
1361 if (!(sd->flags & flag))
1362 break;
1363 hsd = sd;
1364 }
1365
1366 return hsd;
1367}
1368
1369static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1370{
1371 struct sched_domain *sd;
1372
1373 for_each_domain(cpu, sd) {
1374 if (sd->flags & flag)
1375 break;
1376 }
1377
1378 return sd;
1379}
1380
1381DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
1382DECLARE_PER_CPU(int, sd_llc_size);
1383DECLARE_PER_CPU(int, sd_llc_id);
1384DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
1385DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
1386DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
1387DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
1388extern struct static_key_false sched_asym_cpucapacity;
1389
1390struct sched_group_capacity {
1391 atomic_t ref;
1392 /*
1393 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
1394 * for a single CPU.
1395 */
1396 unsigned long capacity;
1397 unsigned long min_capacity; /* Min per-CPU capacity in group */
1398 unsigned long max_capacity; /* Max per-CPU capacity in group */
1399 unsigned long next_update;
1400 int imbalance; /* XXX unrelated to capacity but shared group state */
1401
1402#ifdef CONFIG_SCHED_DEBUG
1403 int id;
1404#endif
1405
1406 unsigned long cpumask[0]; /* Balance mask */
1407};
1408
1409struct sched_group {
1410 struct sched_group *next; /* Must be a circular list */
1411 atomic_t ref;
1412
1413 unsigned int group_weight;
1414 struct sched_group_capacity *sgc;
1415 int asym_prefer_cpu; /* CPU of highest priority in group */
1416
1417 /*
1418 * The CPUs this group covers.
1419 *
1420 * NOTE: this field is variable length. (Allocated dynamically
1421 * by attaching extra space to the end of the structure,
1422 * depending on how many CPUs the kernel has booted up with)
1423 */
1424 unsigned long cpumask[0];
1425};
1426
1427static inline struct cpumask *sched_group_span(struct sched_group *sg)
1428{
1429 return to_cpumask(sg->cpumask);
1430}
1431
1432/*
1433 * See build_balance_mask().
1434 */
1435static inline struct cpumask *group_balance_mask(struct sched_group *sg)
1436{
1437 return to_cpumask(sg->sgc->cpumask);
1438}
1439
1440/**
1441 * group_first_cpu - Returns the first CPU in the cpumask of a sched_group.
1442 * @group: The group whose first CPU is to be returned.
1443 */
1444static inline unsigned int group_first_cpu(struct sched_group *group)
1445{
1446 return cpumask_first(sched_group_span(group));
1447}
1448
1449extern int group_balance_cpu(struct sched_group *sg);
1450
1451#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
1452void register_sched_domain_sysctl(void);
1453void dirty_sched_domain_sysctl(int cpu);
1454void unregister_sched_domain_sysctl(void);
1455#else
1456static inline void register_sched_domain_sysctl(void)
1457{
1458}
1459static inline void dirty_sched_domain_sysctl(int cpu)
1460{
1461}
1462static inline void unregister_sched_domain_sysctl(void)
1463{
1464}
1465#endif
1466
1467extern int newidle_balance(struct rq *this_rq, struct rq_flags *rf);
1468
1469#else
1470
1471static inline void sched_ttwu_pending(void) { }
1472
1473static inline int newidle_balance(struct rq *this_rq, struct rq_flags *rf) { return 0; }
1474
1475#endif /* CONFIG_SMP */
1476
1477#include "stats.h"
1478#include "autogroup.h"
1479
1480#ifdef CONFIG_CGROUP_SCHED
1481
1482/*
1483 * Return the group to which this tasks belongs.
1484 *
1485 * We cannot use task_css() and friends because the cgroup subsystem
1486 * changes that value before the cgroup_subsys::attach() method is called,
1487 * therefore we cannot pin it and might observe the wrong value.
1488 *
1489 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
1490 * core changes this before calling sched_move_task().
1491 *
1492 * Instead we use a 'copy' which is updated from sched_move_task() while
1493 * holding both task_struct::pi_lock and rq::lock.
1494 */
1495static inline struct task_group *task_group(struct task_struct *p)
1496{
1497 return p->sched_task_group;
1498}
1499
1500/* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
1501static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
1502{
1503#if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
1504 struct task_group *tg = task_group(p);
1505#endif
1506
1507#ifdef CONFIG_FAIR_GROUP_SCHED
1508 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
1509 p->se.cfs_rq = tg->cfs_rq[cpu];
1510 p->se.parent = tg->se[cpu];
1511#endif
1512
1513#ifdef CONFIG_RT_GROUP_SCHED
1514 p->rt.rt_rq = tg->rt_rq[cpu];
1515 p->rt.parent = tg->rt_se[cpu];
1516#endif
1517}
1518
1519#else /* CONFIG_CGROUP_SCHED */
1520
1521static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
1522static inline struct task_group *task_group(struct task_struct *p)
1523{
1524 return NULL;
1525}
1526
1527#endif /* CONFIG_CGROUP_SCHED */
1528
1529static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
1530{
1531 set_task_rq(p, cpu);
1532#ifdef CONFIG_SMP
1533 /*
1534 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
1535 * successfully executed on another CPU. We must ensure that updates of
1536 * per-task data have been completed by this moment.
1537 */
1538 smp_wmb();
1539#ifdef CONFIG_THREAD_INFO_IN_TASK
1540 WRITE_ONCE(p->cpu, cpu);
1541#else
1542 WRITE_ONCE(task_thread_info(p)->cpu, cpu);
1543#endif
1544 p->wake_cpu = cpu;
1545#endif
1546}
1547
1548/*
1549 * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
1550 */
1551#ifdef CONFIG_SCHED_DEBUG
1552# include <linux/static_key.h>
1553# define const_debug __read_mostly
1554#else
1555# define const_debug const
1556#endif
1557
1558#define SCHED_FEAT(name, enabled) \
1559 __SCHED_FEAT_##name ,
1560
1561enum {
1562#include "features.h"
1563 __SCHED_FEAT_NR,
1564};
1565
1566#undef SCHED_FEAT
1567
Olivier Deprez0e641232021-09-23 10:07:05 +02001568#ifdef CONFIG_SCHED_DEBUG
David Brazdil0f672f62019-12-10 10:32:29 +00001569
1570/*
1571 * To support run-time toggling of sched features, all the translation units
1572 * (but core.c) reference the sysctl_sched_features defined in core.c.
1573 */
1574extern const_debug unsigned int sysctl_sched_features;
1575
Olivier Deprez0e641232021-09-23 10:07:05 +02001576#ifdef CONFIG_JUMP_LABEL
David Brazdil0f672f62019-12-10 10:32:29 +00001577#define SCHED_FEAT(name, enabled) \
1578static __always_inline bool static_branch_##name(struct static_key *key) \
1579{ \
1580 return static_key_##enabled(key); \
1581}
1582
1583#include "features.h"
1584#undef SCHED_FEAT
1585
1586extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
1587#define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
1588
Olivier Deprez0e641232021-09-23 10:07:05 +02001589#else /* !CONFIG_JUMP_LABEL */
1590
1591#define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1592
1593#endif /* CONFIG_JUMP_LABEL */
1594
1595#else /* !SCHED_DEBUG */
David Brazdil0f672f62019-12-10 10:32:29 +00001596
1597/*
1598 * Each translation unit has its own copy of sysctl_sched_features to allow
1599 * constants propagation at compile time and compiler optimization based on
1600 * features default.
1601 */
1602#define SCHED_FEAT(name, enabled) \
1603 (1UL << __SCHED_FEAT_##name) * enabled |
1604static const_debug __maybe_unused unsigned int sysctl_sched_features =
1605#include "features.h"
1606 0;
1607#undef SCHED_FEAT
1608
1609#define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1610
Olivier Deprez0e641232021-09-23 10:07:05 +02001611#endif /* SCHED_DEBUG */
David Brazdil0f672f62019-12-10 10:32:29 +00001612
1613extern struct static_key_false sched_numa_balancing;
1614extern struct static_key_false sched_schedstats;
1615
1616static inline u64 global_rt_period(void)
1617{
1618 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
1619}
1620
1621static inline u64 global_rt_runtime(void)
1622{
1623 if (sysctl_sched_rt_runtime < 0)
1624 return RUNTIME_INF;
1625
1626 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
1627}
1628
1629static inline int task_current(struct rq *rq, struct task_struct *p)
1630{
1631 return rq->curr == p;
1632}
1633
1634static inline int task_running(struct rq *rq, struct task_struct *p)
1635{
1636#ifdef CONFIG_SMP
1637 return p->on_cpu;
1638#else
1639 return task_current(rq, p);
1640#endif
1641}
1642
1643static inline int task_on_rq_queued(struct task_struct *p)
1644{
1645 return p->on_rq == TASK_ON_RQ_QUEUED;
1646}
1647
1648static inline int task_on_rq_migrating(struct task_struct *p)
1649{
1650 return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
1651}
1652
1653/*
1654 * wake flags
1655 */
1656#define WF_SYNC 0x01 /* Waker goes to sleep after wakeup */
1657#define WF_FORK 0x02 /* Child wakeup after fork */
1658#define WF_MIGRATED 0x4 /* Internal use, task got migrated */
1659
1660/*
1661 * To aid in avoiding the subversion of "niceness" due to uneven distribution
1662 * of tasks with abnormal "nice" values across CPUs the contribution that
1663 * each task makes to its run queue's load is weighted according to its
1664 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
1665 * scaled version of the new time slice allocation that they receive on time
1666 * slice expiry etc.
1667 */
1668
1669#define WEIGHT_IDLEPRIO 3
1670#define WMULT_IDLEPRIO 1431655765
1671
1672extern const int sched_prio_to_weight[40];
1673extern const u32 sched_prio_to_wmult[40];
1674
1675/*
1676 * {de,en}queue flags:
1677 *
1678 * DEQUEUE_SLEEP - task is no longer runnable
1679 * ENQUEUE_WAKEUP - task just became runnable
1680 *
1681 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
1682 * are in a known state which allows modification. Such pairs
1683 * should preserve as much state as possible.
1684 *
1685 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
1686 * in the runqueue.
1687 *
1688 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified)
1689 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
1690 * ENQUEUE_MIGRATED - the task was migrated during wakeup
1691 *
1692 */
1693
1694#define DEQUEUE_SLEEP 0x01
1695#define DEQUEUE_SAVE 0x02 /* Matches ENQUEUE_RESTORE */
1696#define DEQUEUE_MOVE 0x04 /* Matches ENQUEUE_MOVE */
1697#define DEQUEUE_NOCLOCK 0x08 /* Matches ENQUEUE_NOCLOCK */
1698
1699#define ENQUEUE_WAKEUP 0x01
1700#define ENQUEUE_RESTORE 0x02
1701#define ENQUEUE_MOVE 0x04
1702#define ENQUEUE_NOCLOCK 0x08
1703
1704#define ENQUEUE_HEAD 0x10
1705#define ENQUEUE_REPLENISH 0x20
1706#ifdef CONFIG_SMP
1707#define ENQUEUE_MIGRATED 0x40
1708#else
1709#define ENQUEUE_MIGRATED 0x00
1710#endif
1711
1712#define RETRY_TASK ((void *)-1UL)
1713
1714struct sched_class {
1715 const struct sched_class *next;
1716
1717#ifdef CONFIG_UCLAMP_TASK
1718 int uclamp_enabled;
1719#endif
1720
1721 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1722 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1723 void (*yield_task) (struct rq *rq);
1724 bool (*yield_to_task)(struct rq *rq, struct task_struct *p, bool preempt);
1725
1726 void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags);
1727
1728 /*
1729 * Both @prev and @rf are optional and may be NULL, in which case the
1730 * caller must already have invoked put_prev_task(rq, prev, rf).
1731 *
1732 * Otherwise it is the responsibility of the pick_next_task() to call
1733 * put_prev_task() on the @prev task or something equivalent, IFF it
1734 * returns a next task.
1735 *
1736 * In that case (@rf != NULL) it may return RETRY_TASK when it finds a
1737 * higher prio class has runnable tasks.
1738 */
1739 struct task_struct * (*pick_next_task)(struct rq *rq,
1740 struct task_struct *prev,
1741 struct rq_flags *rf);
1742 void (*put_prev_task)(struct rq *rq, struct task_struct *p);
Olivier Deprez0e641232021-09-23 10:07:05 +02001743 void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
David Brazdil0f672f62019-12-10 10:32:29 +00001744
1745#ifdef CONFIG_SMP
1746 int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
1747 int (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
1748 void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
1749
1750 void (*task_woken)(struct rq *this_rq, struct task_struct *task);
1751
1752 void (*set_cpus_allowed)(struct task_struct *p,
1753 const struct cpumask *newmask);
1754
1755 void (*rq_online)(struct rq *rq);
1756 void (*rq_offline)(struct rq *rq);
1757#endif
1758
1759 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
1760 void (*task_fork)(struct task_struct *p);
1761 void (*task_dead)(struct task_struct *p);
1762
1763 /*
1764 * The switched_from() call is allowed to drop rq->lock, therefore we
1765 * cannot assume the switched_from/switched_to pair is serliazed by
1766 * rq->lock. They are however serialized by p->pi_lock.
1767 */
1768 void (*switched_from)(struct rq *this_rq, struct task_struct *task);
1769 void (*switched_to) (struct rq *this_rq, struct task_struct *task);
1770 void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1771 int oldprio);
1772
1773 unsigned int (*get_rr_interval)(struct rq *rq,
1774 struct task_struct *task);
1775
1776 void (*update_curr)(struct rq *rq);
1777
1778#define TASK_SET_GROUP 0
1779#define TASK_MOVE_GROUP 1
1780
1781#ifdef CONFIG_FAIR_GROUP_SCHED
1782 void (*task_change_group)(struct task_struct *p, int type);
1783#endif
1784};
1785
1786static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
1787{
1788 WARN_ON_ONCE(rq->curr != prev);
1789 prev->sched_class->put_prev_task(rq, prev);
1790}
1791
1792static inline void set_next_task(struct rq *rq, struct task_struct *next)
1793{
1794 WARN_ON_ONCE(rq->curr != next);
Olivier Deprez0e641232021-09-23 10:07:05 +02001795 next->sched_class->set_next_task(rq, next, false);
David Brazdil0f672f62019-12-10 10:32:29 +00001796}
1797
1798#ifdef CONFIG_SMP
1799#define sched_class_highest (&stop_sched_class)
1800#else
1801#define sched_class_highest (&dl_sched_class)
1802#endif
1803
1804#define for_class_range(class, _from, _to) \
1805 for (class = (_from); class != (_to); class = class->next)
1806
1807#define for_each_class(class) \
1808 for_class_range(class, sched_class_highest, NULL)
1809
1810extern const struct sched_class stop_sched_class;
1811extern const struct sched_class dl_sched_class;
1812extern const struct sched_class rt_sched_class;
1813extern const struct sched_class fair_sched_class;
1814extern const struct sched_class idle_sched_class;
1815
1816static inline bool sched_stop_runnable(struct rq *rq)
1817{
1818 return rq->stop && task_on_rq_queued(rq->stop);
1819}
1820
1821static inline bool sched_dl_runnable(struct rq *rq)
1822{
1823 return rq->dl.dl_nr_running > 0;
1824}
1825
1826static inline bool sched_rt_runnable(struct rq *rq)
1827{
1828 return rq->rt.rt_queued > 0;
1829}
1830
1831static inline bool sched_fair_runnable(struct rq *rq)
1832{
1833 return rq->cfs.nr_running > 0;
1834}
1835
1836#ifdef CONFIG_SMP
1837
1838extern void update_group_capacity(struct sched_domain *sd, int cpu);
1839
1840extern void trigger_load_balance(struct rq *rq);
1841
1842extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask);
1843
1844#endif
1845
1846#ifdef CONFIG_CPU_IDLE
1847static inline void idle_set_state(struct rq *rq,
1848 struct cpuidle_state *idle_state)
1849{
1850 rq->idle_state = idle_state;
1851}
1852
1853static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1854{
1855 SCHED_WARN_ON(!rcu_read_lock_held());
1856
1857 return rq->idle_state;
1858}
1859#else
1860static inline void idle_set_state(struct rq *rq,
1861 struct cpuidle_state *idle_state)
1862{
1863}
1864
1865static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1866{
1867 return NULL;
1868}
1869#endif
1870
1871extern void schedule_idle(void);
1872
1873extern void sysrq_sched_debug_show(void);
1874extern void sched_init_granularity(void);
1875extern void update_max_interval(void);
1876
1877extern void init_sched_dl_class(void);
1878extern void init_sched_rt_class(void);
1879extern void init_sched_fair_class(void);
1880
1881extern void reweight_task(struct task_struct *p, int prio);
1882
1883extern void resched_curr(struct rq *rq);
1884extern void resched_cpu(int cpu);
1885
1886extern struct rt_bandwidth def_rt_bandwidth;
1887extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
1888
1889extern struct dl_bandwidth def_dl_bandwidth;
1890extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
1891extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
1892extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se);
1893extern void init_dl_rq_bw_ratio(struct dl_rq *dl_rq);
1894
1895#define BW_SHIFT 20
1896#define BW_UNIT (1 << BW_SHIFT)
1897#define RATIO_SHIFT 8
Olivier Deprez0e641232021-09-23 10:07:05 +02001898#define MAX_BW_BITS (64 - BW_SHIFT)
1899#define MAX_BW ((1ULL << MAX_BW_BITS) - 1)
David Brazdil0f672f62019-12-10 10:32:29 +00001900unsigned long to_ratio(u64 period, u64 runtime);
1901
1902extern void init_entity_runnable_average(struct sched_entity *se);
1903extern void post_init_entity_util_avg(struct task_struct *p);
1904
1905#ifdef CONFIG_NO_HZ_FULL
1906extern bool sched_can_stop_tick(struct rq *rq);
1907extern int __init sched_tick_offload_init(void);
1908
1909/*
1910 * Tick may be needed by tasks in the runqueue depending on their policy and
1911 * requirements. If tick is needed, lets send the target an IPI to kick it out of
1912 * nohz mode if necessary.
1913 */
1914static inline void sched_update_tick_dependency(struct rq *rq)
1915{
1916 int cpu;
1917
1918 if (!tick_nohz_full_enabled())
1919 return;
1920
1921 cpu = cpu_of(rq);
1922
1923 if (!tick_nohz_full_cpu(cpu))
1924 return;
1925
1926 if (sched_can_stop_tick(rq))
1927 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
1928 else
1929 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
1930}
1931#else
1932static inline int sched_tick_offload_init(void) { return 0; }
1933static inline void sched_update_tick_dependency(struct rq *rq) { }
1934#endif
1935
1936static inline void add_nr_running(struct rq *rq, unsigned count)
1937{
1938 unsigned prev_nr = rq->nr_running;
1939
1940 rq->nr_running = prev_nr + count;
1941
1942#ifdef CONFIG_SMP
1943 if (prev_nr < 2 && rq->nr_running >= 2) {
1944 if (!READ_ONCE(rq->rd->overload))
1945 WRITE_ONCE(rq->rd->overload, 1);
1946 }
1947#endif
1948
1949 sched_update_tick_dependency(rq);
1950}
1951
1952static inline void sub_nr_running(struct rq *rq, unsigned count)
1953{
1954 rq->nr_running -= count;
1955 /* Check if we still need preemption */
1956 sched_update_tick_dependency(rq);
1957}
1958
1959extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
1960extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
1961
1962extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
1963
1964extern const_debug unsigned int sysctl_sched_nr_migrate;
1965extern const_debug unsigned int sysctl_sched_migration_cost;
1966
1967#ifdef CONFIG_SCHED_HRTICK
1968
1969/*
1970 * Use hrtick when:
1971 * - enabled by features
1972 * - hrtimer is actually high res
1973 */
1974static inline int hrtick_enabled(struct rq *rq)
1975{
1976 if (!sched_feat(HRTICK))
1977 return 0;
1978 if (!cpu_active(cpu_of(rq)))
1979 return 0;
1980 return hrtimer_is_hres_active(&rq->hrtick_timer);
1981}
1982
1983void hrtick_start(struct rq *rq, u64 delay);
1984
1985#else
1986
1987static inline int hrtick_enabled(struct rq *rq)
1988{
1989 return 0;
1990}
1991
1992#endif /* CONFIG_SCHED_HRTICK */
1993
1994#ifndef arch_scale_freq_capacity
1995static __always_inline
1996unsigned long arch_scale_freq_capacity(int cpu)
1997{
1998 return SCHED_CAPACITY_SCALE;
1999}
2000#endif
2001
2002#ifdef CONFIG_SMP
2003#ifdef CONFIG_PREEMPTION
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00002004
2005static inline void double_rq_lock(struct rq *rq1, struct rq *rq2);
2006
2007/*
2008 * fair double_lock_balance: Safely acquires both rq->locks in a fair
2009 * way at the expense of forcing extra atomic operations in all
2010 * invocations. This assures that the double_lock is acquired using the
2011 * same underlying policy as the spinlock_t on this architecture, which
2012 * reduces latency compared to the unfair variant below. However, it
2013 * also adds more overhead and therefore may reduce throughput.
2014 */
2015static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2016 __releases(this_rq->lock)
2017 __acquires(busiest->lock)
2018 __acquires(this_rq->lock)
2019{
2020 raw_spin_unlock(&this_rq->lock);
2021 double_rq_lock(this_rq, busiest);
2022
2023 return 1;
2024}
2025
2026#else
2027/*
2028 * Unfair double_lock_balance: Optimizes throughput at the expense of
2029 * latency by eliminating extra atomic operations when the locks are
2030 * already in proper order on entry. This favors lower CPU-ids and will
2031 * grant the double lock to lower CPUs over higher ids under contention,
2032 * regardless of entry order into the function.
2033 */
2034static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2035 __releases(this_rq->lock)
2036 __acquires(busiest->lock)
2037 __acquires(this_rq->lock)
2038{
2039 int ret = 0;
2040
2041 if (unlikely(!raw_spin_trylock(&busiest->lock))) {
2042 if (busiest < this_rq) {
2043 raw_spin_unlock(&this_rq->lock);
2044 raw_spin_lock(&busiest->lock);
2045 raw_spin_lock_nested(&this_rq->lock,
2046 SINGLE_DEPTH_NESTING);
2047 ret = 1;
2048 } else
2049 raw_spin_lock_nested(&busiest->lock,
2050 SINGLE_DEPTH_NESTING);
2051 }
2052 return ret;
2053}
2054
David Brazdil0f672f62019-12-10 10:32:29 +00002055#endif /* CONFIG_PREEMPTION */
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00002056
2057/*
2058 * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
2059 */
2060static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
2061{
2062 if (unlikely(!irqs_disabled())) {
2063 /* printk() doesn't work well under rq->lock */
2064 raw_spin_unlock(&this_rq->lock);
2065 BUG_ON(1);
2066 }
2067
2068 return _double_lock_balance(this_rq, busiest);
2069}
2070
2071static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
2072 __releases(busiest->lock)
2073{
2074 raw_spin_unlock(&busiest->lock);
2075 lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
2076}
2077
2078static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
2079{
2080 if (l1 > l2)
2081 swap(l1, l2);
2082
2083 spin_lock(l1);
2084 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2085}
2086
2087static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
2088{
2089 if (l1 > l2)
2090 swap(l1, l2);
2091
2092 spin_lock_irq(l1);
2093 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2094}
2095
2096static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
2097{
2098 if (l1 > l2)
2099 swap(l1, l2);
2100
2101 raw_spin_lock(l1);
2102 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2103}
2104
2105/*
2106 * double_rq_lock - safely lock two runqueues
2107 *
2108 * Note this does not disable interrupts like task_rq_lock,
2109 * you need to do so manually before calling.
2110 */
2111static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2112 __acquires(rq1->lock)
2113 __acquires(rq2->lock)
2114{
2115 BUG_ON(!irqs_disabled());
2116 if (rq1 == rq2) {
2117 raw_spin_lock(&rq1->lock);
2118 __acquire(rq2->lock); /* Fake it out ;) */
2119 } else {
2120 if (rq1 < rq2) {
2121 raw_spin_lock(&rq1->lock);
2122 raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
2123 } else {
2124 raw_spin_lock(&rq2->lock);
2125 raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
2126 }
2127 }
2128}
2129
2130/*
2131 * double_rq_unlock - safely unlock two runqueues
2132 *
2133 * Note this does not restore interrupts like task_rq_unlock,
2134 * you need to do so manually after calling.
2135 */
2136static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2137 __releases(rq1->lock)
2138 __releases(rq2->lock)
2139{
2140 raw_spin_unlock(&rq1->lock);
2141 if (rq1 != rq2)
2142 raw_spin_unlock(&rq2->lock);
2143 else
2144 __release(rq2->lock);
2145}
2146
2147extern void set_rq_online (struct rq *rq);
2148extern void set_rq_offline(struct rq *rq);
2149extern bool sched_smp_initialized;
2150
2151#else /* CONFIG_SMP */
2152
2153/*
2154 * double_rq_lock - safely lock two runqueues
2155 *
2156 * Note this does not disable interrupts like task_rq_lock,
2157 * you need to do so manually before calling.
2158 */
2159static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2160 __acquires(rq1->lock)
2161 __acquires(rq2->lock)
2162{
2163 BUG_ON(!irqs_disabled());
2164 BUG_ON(rq1 != rq2);
2165 raw_spin_lock(&rq1->lock);
2166 __acquire(rq2->lock); /* Fake it out ;) */
2167}
2168
2169/*
2170 * double_rq_unlock - safely unlock two runqueues
2171 *
2172 * Note this does not restore interrupts like task_rq_unlock,
2173 * you need to do so manually after calling.
2174 */
2175static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2176 __releases(rq1->lock)
2177 __releases(rq2->lock)
2178{
2179 BUG_ON(rq1 != rq2);
2180 raw_spin_unlock(&rq1->lock);
2181 __release(rq2->lock);
2182}
2183
2184#endif
2185
2186extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
2187extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
2188
2189#ifdef CONFIG_SCHED_DEBUG
2190extern bool sched_debug_enabled;
2191
2192extern void print_cfs_stats(struct seq_file *m, int cpu);
2193extern void print_rt_stats(struct seq_file *m, int cpu);
2194extern void print_dl_stats(struct seq_file *m, int cpu);
2195extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
2196extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
2197extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
2198#ifdef CONFIG_NUMA_BALANCING
2199extern void
2200show_numa_stats(struct task_struct *p, struct seq_file *m);
2201extern void
2202print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
2203 unsigned long tpf, unsigned long gsf, unsigned long gpf);
2204#endif /* CONFIG_NUMA_BALANCING */
2205#endif /* CONFIG_SCHED_DEBUG */
2206
2207extern void init_cfs_rq(struct cfs_rq *cfs_rq);
2208extern void init_rt_rq(struct rt_rq *rt_rq);
2209extern void init_dl_rq(struct dl_rq *dl_rq);
2210
2211extern void cfs_bandwidth_usage_inc(void);
2212extern void cfs_bandwidth_usage_dec(void);
2213
2214#ifdef CONFIG_NO_HZ_COMMON
2215#define NOHZ_BALANCE_KICK_BIT 0
2216#define NOHZ_STATS_KICK_BIT 1
2217
2218#define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT)
2219#define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT)
2220
2221#define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK)
2222
2223#define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
2224
2225extern void nohz_balance_exit_idle(struct rq *rq);
2226#else
2227static inline void nohz_balance_exit_idle(struct rq *rq) { }
2228#endif
2229
2230
2231#ifdef CONFIG_SMP
2232static inline
2233void __dl_update(struct dl_bw *dl_b, s64 bw)
2234{
2235 struct root_domain *rd = container_of(dl_b, struct root_domain, dl_bw);
2236 int i;
2237
2238 RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
2239 "sched RCU must be held");
2240 for_each_cpu_and(i, rd->span, cpu_active_mask) {
2241 struct rq *rq = cpu_rq(i);
2242
2243 rq->dl.extra_bw += bw;
2244 }
2245}
2246#else
2247static inline
2248void __dl_update(struct dl_bw *dl_b, s64 bw)
2249{
2250 struct dl_rq *dl = container_of(dl_b, struct dl_rq, dl_bw);
2251
2252 dl->extra_bw += bw;
2253}
2254#endif
2255
2256
2257#ifdef CONFIG_IRQ_TIME_ACCOUNTING
2258struct irqtime {
2259 u64 total;
2260 u64 tick_delta;
2261 u64 irq_start_time;
2262 struct u64_stats_sync sync;
2263};
2264
2265DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
2266
2267/*
2268 * Returns the irqtime minus the softirq time computed by ksoftirqd.
2269 * Otherwise ksoftirqd's sum_exec_runtime is substracted its own runtime
2270 * and never move forward.
2271 */
2272static inline u64 irq_time_read(int cpu)
2273{
2274 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
2275 unsigned int seq;
2276 u64 total;
2277
2278 do {
2279 seq = __u64_stats_fetch_begin(&irqtime->sync);
2280 total = irqtime->total;
2281 } while (__u64_stats_fetch_retry(&irqtime->sync, seq));
2282
2283 return total;
2284}
2285#endif /* CONFIG_IRQ_TIME_ACCOUNTING */
2286
2287#ifdef CONFIG_CPU_FREQ
David Brazdil0f672f62019-12-10 10:32:29 +00002288DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00002289
2290/**
2291 * cpufreq_update_util - Take a note about CPU utilization changes.
2292 * @rq: Runqueue to carry out the update for.
2293 * @flags: Update reason flags.
2294 *
2295 * This function is called by the scheduler on the CPU whose utilization is
2296 * being updated.
2297 *
2298 * It can only be called from RCU-sched read-side critical sections.
2299 *
2300 * The way cpufreq is currently arranged requires it to evaluate the CPU
2301 * performance state (frequency/voltage) on a regular basis to prevent it from
2302 * being stuck in a completely inadequate performance level for too long.
2303 * That is not guaranteed to happen if the updates are only triggered from CFS
2304 * and DL, though, because they may not be coming in if only RT tasks are
2305 * active all the time (or there are RT tasks only).
2306 *
2307 * As a workaround for that issue, this function is called periodically by the
2308 * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
2309 * but that really is a band-aid. Going forward it should be replaced with
2310 * solutions targeted more specifically at RT tasks.
2311 */
2312static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
2313{
2314 struct update_util_data *data;
2315
2316 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
2317 cpu_of(rq)));
2318 if (data)
2319 data->func(data, rq_clock(rq), flags);
2320}
2321#else
2322static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
2323#endif /* CONFIG_CPU_FREQ */
2324
David Brazdil0f672f62019-12-10 10:32:29 +00002325#ifdef CONFIG_UCLAMP_TASK
Olivier Deprez0e641232021-09-23 10:07:05 +02002326unsigned int uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
David Brazdil0f672f62019-12-10 10:32:29 +00002327
Olivier Deprez0e641232021-09-23 10:07:05 +02002328/**
2329 * uclamp_util_with - clamp @util with @rq and @p effective uclamp values.
2330 * @rq: The rq to clamp against. Must not be NULL.
2331 * @util: The util value to clamp.
2332 * @p: The task to clamp against. Can be NULL if you want to clamp
2333 * against @rq only.
2334 *
2335 * Clamps the passed @util to the max(@rq, @p) effective uclamp values.
2336 *
2337 * If sched_uclamp_used static key is disabled, then just return the util
2338 * without any clamping since uclamp aggregation at the rq level in the fast
2339 * path is disabled, rendering this operation a NOP.
2340 *
2341 * Use uclamp_eff_value() if you don't care about uclamp values at rq level. It
2342 * will return the correct effective uclamp value of the task even if the
2343 * static key is disabled.
2344 */
David Brazdil0f672f62019-12-10 10:32:29 +00002345static __always_inline
2346unsigned int uclamp_util_with(struct rq *rq, unsigned int util,
2347 struct task_struct *p)
2348{
Olivier Deprez0e641232021-09-23 10:07:05 +02002349 unsigned int min_util;
2350 unsigned int max_util;
2351
2352 if (!static_branch_likely(&sched_uclamp_used))
2353 return util;
2354
2355 min_util = READ_ONCE(rq->uclamp[UCLAMP_MIN].value);
2356 max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
David Brazdil0f672f62019-12-10 10:32:29 +00002357
2358 if (p) {
2359 min_util = max(min_util, uclamp_eff_value(p, UCLAMP_MIN));
2360 max_util = max(max_util, uclamp_eff_value(p, UCLAMP_MAX));
2361 }
2362
2363 /*
2364 * Since CPU's {min,max}_util clamps are MAX aggregated considering
2365 * RUNNABLE tasks with _different_ clamps, we can end up with an
2366 * inversion. Fix it now when the clamps are applied.
2367 */
2368 if (unlikely(min_util >= max_util))
2369 return min_util;
2370
2371 return clamp(util, min_util, max_util);
2372}
2373
2374static inline unsigned int uclamp_util(struct rq *rq, unsigned int util)
2375{
2376 return uclamp_util_with(rq, util, NULL);
2377}
Olivier Deprez0e641232021-09-23 10:07:05 +02002378
2379/*
2380 * When uclamp is compiled in, the aggregation at rq level is 'turned off'
2381 * by default in the fast path and only gets turned on once userspace performs
2382 * an operation that requires it.
2383 *
2384 * Returns true if userspace opted-in to use uclamp and aggregation at rq level
2385 * hence is active.
2386 */
2387static inline bool uclamp_is_used(void)
2388{
2389 return static_branch_likely(&sched_uclamp_used);
2390}
David Brazdil0f672f62019-12-10 10:32:29 +00002391#else /* CONFIG_UCLAMP_TASK */
2392static inline unsigned int uclamp_util_with(struct rq *rq, unsigned int util,
2393 struct task_struct *p)
2394{
2395 return util;
2396}
2397static inline unsigned int uclamp_util(struct rq *rq, unsigned int util)
2398{
2399 return util;
2400}
Olivier Deprez0e641232021-09-23 10:07:05 +02002401
2402static inline bool uclamp_is_used(void)
2403{
2404 return false;
2405}
David Brazdil0f672f62019-12-10 10:32:29 +00002406#endif /* CONFIG_UCLAMP_TASK */
2407
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00002408#ifdef arch_scale_freq_capacity
2409# ifndef arch_scale_freq_invariant
2410# define arch_scale_freq_invariant() true
2411# endif
2412#else
2413# define arch_scale_freq_invariant() false
2414#endif
2415
David Brazdil0f672f62019-12-10 10:32:29 +00002416#ifdef CONFIG_SMP
2417static inline unsigned long capacity_orig_of(int cpu)
2418{
2419 return cpu_rq(cpu)->cpu_capacity_orig;
2420}
2421#endif
2422
2423/**
2424 * enum schedutil_type - CPU utilization type
2425 * @FREQUENCY_UTIL: Utilization used to select frequency
2426 * @ENERGY_UTIL: Utilization used during energy calculation
2427 *
2428 * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time
2429 * need to be aggregated differently depending on the usage made of them. This
2430 * enum is used within schedutil_freq_util() to differentiate the types of
2431 * utilization expected by the callers, and adjust the aggregation accordingly.
2432 */
2433enum schedutil_type {
2434 FREQUENCY_UTIL,
2435 ENERGY_UTIL,
2436};
2437
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00002438#ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
David Brazdil0f672f62019-12-10 10:32:29 +00002439
2440unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
2441 unsigned long max, enum schedutil_type type,
2442 struct task_struct *p);
2443
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00002444static inline unsigned long cpu_bw_dl(struct rq *rq)
2445{
2446 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
2447}
2448
2449static inline unsigned long cpu_util_dl(struct rq *rq)
2450{
2451 return READ_ONCE(rq->avg_dl.util_avg);
2452}
2453
2454static inline unsigned long cpu_util_cfs(struct rq *rq)
2455{
2456 unsigned long util = READ_ONCE(rq->cfs.avg.util_avg);
2457
2458 if (sched_feat(UTIL_EST)) {
2459 util = max_t(unsigned long, util,
2460 READ_ONCE(rq->cfs.avg.util_est.enqueued));
2461 }
2462
2463 return util;
2464}
2465
2466static inline unsigned long cpu_util_rt(struct rq *rq)
2467{
2468 return READ_ONCE(rq->avg_rt.util_avg);
2469}
David Brazdil0f672f62019-12-10 10:32:29 +00002470#else /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
2471static inline unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
2472 unsigned long max, enum schedutil_type type,
2473 struct task_struct *p)
2474{
2475 return 0;
2476}
2477#endif /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00002478
2479#ifdef CONFIG_HAVE_SCHED_AVG_IRQ
2480static inline unsigned long cpu_util_irq(struct rq *rq)
2481{
2482 return rq->avg_irq.util_avg;
2483}
2484
2485static inline
2486unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2487{
2488 util *= (max - irq);
2489 util /= max;
2490
2491 return util;
2492
2493}
2494#else
2495static inline unsigned long cpu_util_irq(struct rq *rq)
2496{
2497 return 0;
2498}
2499
2500static inline
2501unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2502{
2503 return util;
2504}
2505#endif
David Brazdil0f672f62019-12-10 10:32:29 +00002506
2507#if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
2508
2509#define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
2510
2511DECLARE_STATIC_KEY_FALSE(sched_energy_present);
2512
2513static inline bool sched_energy_enabled(void)
2514{
2515 return static_branch_unlikely(&sched_energy_present);
2516}
2517
2518#else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
2519
2520#define perf_domain_span(pd) NULL
2521static inline bool sched_energy_enabled(void) { return false; }
2522
2523#endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
2524
2525#ifdef CONFIG_MEMBARRIER
2526/*
2527 * The scheduler provides memory barriers required by membarrier between:
2528 * - prior user-space memory accesses and store to rq->membarrier_state,
2529 * - store to rq->membarrier_state and following user-space memory accesses.
2530 * In the same way it provides those guarantees around store to rq->curr.
2531 */
2532static inline void membarrier_switch_mm(struct rq *rq,
2533 struct mm_struct *prev_mm,
2534 struct mm_struct *next_mm)
2535{
2536 int membarrier_state;
2537
2538 if (prev_mm == next_mm)
2539 return;
2540
2541 membarrier_state = atomic_read(&next_mm->membarrier_state);
2542 if (READ_ONCE(rq->membarrier_state) == membarrier_state)
2543 return;
2544
2545 WRITE_ONCE(rq->membarrier_state, membarrier_state);
2546}
2547#else
2548static inline void membarrier_switch_mm(struct rq *rq,
2549 struct mm_struct *prev_mm,
2550 struct mm_struct *next_mm)
2551{
2552}
2553#endif