1 /* 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>
48 #include <linux/energy_model.h>
49 #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>
59 #include <linux/psi.h>
60 #include <linux/rcupdate_wait.h>
61 #include <linux/security.h>
62 #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
84 struct rq;
85 struct cpuidle_state;
86
87 /* task_struct::on_rq states: */
88 #define TASK_ON_RQ_QUEUED 1
89 #define TASK_ON_RQ_MIGRATING 2
90
91 extern __read_mostly int scheduler_running;
92
93 extern unsigned long calc_load_update;
94 extern atomic_long_t calc_load_tasks;
95
96 extern void calc_global_load_tick(struct rq *this_rq);
97 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
98
99 /*
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)
121 # define scale_load_down(w) ((w) >> SCHED_FIXEDPOINT_SHIFT)
122 #else
123 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT)
124 # define scale_load(w) (w)
125 # define scale_load_down(w) (w)
126 #endif
127
128 /*
129 * Task weight (visible to users) and its load (invisible to users) have
130 * independent resolution, but they should be well calibrated. We use
131 * scale_load() and scale_load_down(w) to convert between them. The
132 * following must be true:
133 *
134 * scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD
135 *
136 */
137 #define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT)
138
139 /*
140 * Single value that decides SCHED_DEADLINE internal math precision.
141 * 10 -> just above 1us
142 * 9 -> just above 0.5us
143 */
144 #define DL_SCALE 10
145
146 /*
147 * Single value that denotes runtime == period, ie unlimited time.
148 */
149 #define RUNTIME_INF ((u64)~0ULL)
150
idle_policy(int policy)151 static inline int idle_policy(int policy)
152 {
153 return policy == SCHED_IDLE;
154 }
fair_policy(int policy)155 static inline int fair_policy(int policy)
156 {
157 return policy == SCHED_NORMAL || policy == SCHED_BATCH;
158 }
159
rt_policy(int policy)160 static inline int rt_policy(int policy)
161 {
162 return policy == SCHED_FIFO || policy == SCHED_RR;
163 }
164
dl_policy(int policy)165 static inline int dl_policy(int policy)
166 {
167 return policy == SCHED_DEADLINE;
168 }
valid_policy(int policy)169 static inline bool valid_policy(int policy)
170 {
171 return idle_policy(policy) || fair_policy(policy) ||
172 rt_policy(policy) || dl_policy(policy);
173 }
174
task_has_idle_policy(struct task_struct * p)175 static inline int task_has_idle_policy(struct task_struct *p)
176 {
177 return idle_policy(p->policy);
178 }
179
task_has_rt_policy(struct task_struct * p)180 static inline int task_has_rt_policy(struct task_struct *p)
181 {
182 return rt_policy(p->policy);
183 }
184
task_has_dl_policy(struct task_struct * p)185 static inline int task_has_dl_policy(struct task_struct *p)
186 {
187 return dl_policy(p->policy);
188 }
189
190 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
191
192 /*
193 * !! For sched_setattr_nocheck() (kernel) only !!
194 *
195 * This is actually gross. :(
196 *
197 * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
198 * tasks, but still be able to sleep. We need this on platforms that cannot
199 * atomically change clock frequency. Remove once fast switching will be
200 * available on such platforms.
201 *
202 * SUGOV stands for SchedUtil GOVernor.
203 */
204 #define SCHED_FLAG_SUGOV 0x10000000
205
dl_entity_is_special(struct sched_dl_entity * dl_se)206 static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se)
207 {
208 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
209 return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
210 #else
211 return false;
212 #endif
213 }
214
215 /*
216 * Tells if entity @a should preempt entity @b.
217 */
218 static inline bool
dl_entity_preempt(struct sched_dl_entity * a,struct sched_dl_entity * b)219 dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
220 {
221 return dl_entity_is_special(a) ||
222 dl_time_before(a->deadline, b->deadline);
223 }
224
225 /*
226 * This is the priority-queue data structure of the RT scheduling class:
227 */
228 struct rt_prio_array {
229 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
230 struct list_head queue[MAX_RT_PRIO];
231 };
232
233 struct rt_bandwidth {
234 /* nests inside the rq lock: */
235 raw_spinlock_t rt_runtime_lock;
236 ktime_t rt_period;
237 u64 rt_runtime;
238 struct hrtimer rt_period_timer;
239 unsigned int rt_period_active;
240 };
241
242 void __dl_clear_params(struct task_struct *p);
243
244 /*
245 * To keep the bandwidth of -deadline tasks and groups under control
246 * we need some place where:
247 * - store the maximum -deadline bandwidth of the system (the group);
248 * - cache the fraction of that bandwidth that is currently allocated.
249 *
250 * This is all done in the data structure below. It is similar to the
251 * one used for RT-throttling (rt_bandwidth), with the main difference
252 * that, since here we are only interested in admission control, we
253 * do not decrease any runtime while the group "executes", neither we
254 * need a timer to replenish it.
255 *
256 * With respect to SMP, the bandwidth is given on a per-CPU basis,
257 * meaning that:
258 * - dl_bw (< 100%) is the bandwidth of the system (group) on each CPU;
259 * - dl_total_bw array contains, in the i-eth element, the currently
260 * allocated bandwidth on the i-eth CPU.
261 * Moreover, groups consume bandwidth on each CPU, while tasks only
262 * consume bandwidth on the CPU they're running on.
263 * Finally, dl_total_bw_cpu is used to cache the index of dl_total_bw
264 * that will be shown the next time the proc or cgroup controls will
265 * be red. It on its turn can be changed by writing on its own
266 * control.
267 */
268 struct dl_bandwidth {
269 raw_spinlock_t dl_runtime_lock;
270 u64 dl_runtime;
271 u64 dl_period;
272 };
273
dl_bandwidth_enabled(void)274 static inline int dl_bandwidth_enabled(void)
275 {
276 return sysctl_sched_rt_runtime >= 0;
277 }
278
279 struct dl_bw {
280 raw_spinlock_t lock;
281 u64 bw;
282 u64 total_bw;
283 };
284
285 static inline void __dl_update(struct dl_bw *dl_b, s64 bw);
286
287 static inline
__dl_sub(struct dl_bw * dl_b,u64 tsk_bw,int cpus)288 void __dl_sub(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
289 {
290 dl_b->total_bw -= tsk_bw;
291 __dl_update(dl_b, (s32)tsk_bw / cpus);
292 }
293
294 static inline
__dl_add(struct dl_bw * dl_b,u64 tsk_bw,int cpus)295 void __dl_add(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
296 {
297 dl_b->total_bw += tsk_bw;
298 __dl_update(dl_b, -((s32)tsk_bw / cpus));
299 }
300
301 static inline
__dl_overflow(struct dl_bw * dl_b,int cpus,u64 old_bw,u64 new_bw)302 bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw)
303 {
304 return dl_b->bw != -1 &&
305 dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw;
306 }
307
308 extern void dl_change_utilization(struct task_struct *p, u64 new_bw);
309 extern void init_dl_bw(struct dl_bw *dl_b);
310 extern int sched_dl_global_validate(void);
311 extern void sched_dl_do_global(void);
312 extern int sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
313 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
314 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
315 extern bool __checkparam_dl(const struct sched_attr *attr);
316 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
317 extern int dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
318 extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
319 extern bool dl_cpu_busy(unsigned int cpu);
320
321 #ifdef CONFIG_CGROUP_SCHED
322
323 #include <linux/cgroup.h>
324 #include <linux/psi.h>
325
326 struct cfs_rq;
327 struct rt_rq;
328
329 extern struct list_head task_groups;
330
331 struct cfs_bandwidth {
332 #ifdef CONFIG_CFS_BANDWIDTH
333 raw_spinlock_t lock;
334 ktime_t period;
335 u64 quota;
336 u64 runtime;
337 s64 hierarchical_quota;
338
339 u8 idle;
340 u8 period_active;
341 u8 distribute_running;
342 u8 slack_started;
343 struct hrtimer period_timer;
344 struct hrtimer slack_timer;
345 struct list_head throttled_cfs_rq;
346
347 /* Statistics: */
348 int nr_periods;
349 int nr_throttled;
350 u64 throttled_time;
351 #endif
352 };
353
354 /* Task group related information */
355 struct task_group {
356 struct cgroup_subsys_state css;
357
358 #ifdef CONFIG_FAIR_GROUP_SCHED
359 /* schedulable entities of this group on each CPU */
360 struct sched_entity **se;
361 /* runqueue "owned" by this group on each CPU */
362 struct cfs_rq **cfs_rq;
363 unsigned long shares;
364
365 #ifdef CONFIG_SMP
366 /*
367 * load_avg can be heavily contended at clock tick time, so put
368 * it in its own cacheline separated from the fields above which
369 * will also be accessed at each tick.
370 */
371 atomic_long_t load_avg ____cacheline_aligned;
372 #endif
373 #endif
374
375 #ifdef CONFIG_RT_GROUP_SCHED
376 struct sched_rt_entity **rt_se;
377 struct rt_rq **rt_rq;
378
379 struct rt_bandwidth rt_bandwidth;
380 #endif
381
382 struct rcu_head rcu;
383 struct list_head list;
384
385 struct task_group *parent;
386 struct list_head siblings;
387 struct list_head children;
388
389 #ifdef CONFIG_SCHED_AUTOGROUP
390 struct autogroup *autogroup;
391 #endif
392
393 struct cfs_bandwidth cfs_bandwidth;
394
395 #ifdef CONFIG_UCLAMP_TASK_GROUP
396 /* The two decimal precision [%] value requested from user-space */
397 unsigned int uclamp_pct[UCLAMP_CNT];
398 /* Clamp values requested for a task group */
399 struct uclamp_se uclamp_req[UCLAMP_CNT];
400 /* Effective clamp values used for a task group */
401 struct uclamp_se uclamp[UCLAMP_CNT];
402 #endif
403
404 };
405
406 #ifdef CONFIG_FAIR_GROUP_SCHED
407 #define ROOT_TASK_GROUP_LOAD NICE_0_LOAD
408
409 /*
410 * A weight of 0 or 1 can cause arithmetics problems.
411 * A weight of a cfs_rq is the sum of weights of which entities
412 * are queued on this cfs_rq, so a weight of a entity should not be
413 * too large, so as the shares value of a task group.
414 * (The default weight is 1024 - so there's no practical
415 * limitation from this.)
416 */
417 #define MIN_SHARES (1UL << 1)
418 #define MAX_SHARES (1UL << 18)
419 #endif
420
421 typedef int (*tg_visitor)(struct task_group *, void *);
422
423 extern int walk_tg_tree_from(struct task_group *from,
424 tg_visitor down, tg_visitor up, void *data);
425
426 /*
427 * Iterate the full tree, calling @down when first entering a node and @up when
428 * leaving it for the final time.
429 *
430 * Caller must hold rcu_lock or sufficient equivalent.
431 */
walk_tg_tree(tg_visitor down,tg_visitor up,void * data)432 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
433 {
434 return walk_tg_tree_from(&root_task_group, down, up, data);
435 }
436
437 extern int tg_nop(struct task_group *tg, void *data);
438
439 extern void free_fair_sched_group(struct task_group *tg);
440 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
441 extern void online_fair_sched_group(struct task_group *tg);
442 extern void unregister_fair_sched_group(struct task_group *tg);
443 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
444 struct sched_entity *se, int cpu,
445 struct sched_entity *parent);
446 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
447
448 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
449 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
450 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
451
452 extern void free_rt_sched_group(struct task_group *tg);
453 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
454 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
455 struct sched_rt_entity *rt_se, int cpu,
456 struct sched_rt_entity *parent);
457 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
458 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
459 extern long sched_group_rt_runtime(struct task_group *tg);
460 extern long sched_group_rt_period(struct task_group *tg);
461 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
462
463 extern struct task_group *sched_create_group(struct task_group *parent);
464 extern void sched_online_group(struct task_group *tg,
465 struct task_group *parent);
466 extern void sched_destroy_group(struct task_group *tg);
467 extern void sched_offline_group(struct task_group *tg);
468
469 extern void sched_move_task(struct task_struct *tsk);
470
471 #ifdef CONFIG_FAIR_GROUP_SCHED
472 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
473
474 #ifdef CONFIG_SMP
475 extern void set_task_rq_fair(struct sched_entity *se,
476 struct cfs_rq *prev, struct cfs_rq *next);
477 #else /* !CONFIG_SMP */
set_task_rq_fair(struct sched_entity * se,struct cfs_rq * prev,struct cfs_rq * next)478 static inline void set_task_rq_fair(struct sched_entity *se,
479 struct cfs_rq *prev, struct cfs_rq *next) { }
480 #endif /* CONFIG_SMP */
481 #endif /* CONFIG_FAIR_GROUP_SCHED */
482
483 #else /* CONFIG_CGROUP_SCHED */
484
485 struct cfs_bandwidth { };
486
487 #endif /* CONFIG_CGROUP_SCHED */
488
489 /* CFS-related fields in a runqueue */
490 struct cfs_rq {
491 struct load_weight load;
492 unsigned long runnable_weight;
493 unsigned int nr_running;
494 unsigned int h_nr_running; /* SCHED_{NORMAL,BATCH,IDLE} */
495 unsigned int idle_h_nr_running; /* SCHED_IDLE */
496
497 u64 exec_clock;
498 u64 min_vruntime;
499 #ifndef CONFIG_64BIT
500 u64 min_vruntime_copy;
501 #endif
502
503 struct rb_root_cached tasks_timeline;
504
505 /*
506 * 'curr' points to currently running entity on this cfs_rq.
507 * It is set to NULL otherwise (i.e when none are currently running).
508 */
509 struct sched_entity *curr;
510 struct sched_entity *next;
511 struct sched_entity *last;
512 struct sched_entity *skip;
513
514 #ifdef CONFIG_SCHED_DEBUG
515 unsigned int nr_spread_over;
516 #endif
517
518 #ifdef CONFIG_SMP
519 /*
520 * CFS load tracking
521 */
522 struct sched_avg avg;
523 #ifndef CONFIG_64BIT
524 u64 load_last_update_time_copy;
525 #endif
526 struct {
527 raw_spinlock_t lock ____cacheline_aligned;
528 int nr;
529 unsigned long load_avg;
530 unsigned long util_avg;
531 unsigned long runnable_sum;
532 } removed;
533
534 #ifdef CONFIG_FAIR_GROUP_SCHED
535 unsigned long tg_load_avg_contrib;
536 long propagate;
537 long prop_runnable_sum;
538
539 /*
540 * h_load = weight * f(tg)
541 *
542 * Where f(tg) is the recursive weight fraction assigned to
543 * this group.
544 */
545 unsigned long h_load;
546 u64 last_h_load_update;
547 struct sched_entity *h_load_next;
548 #endif /* CONFIG_FAIR_GROUP_SCHED */
549 #endif /* CONFIG_SMP */
550
551 #ifdef CONFIG_FAIR_GROUP_SCHED
552 struct rq *rq; /* CPU runqueue to which this cfs_rq is attached */
553
554 /*
555 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
556 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
557 * (like users, containers etc.)
558 *
559 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
560 * This list is used during load balance.
561 */
562 int on_list;
563 struct list_head leaf_cfs_rq_list;
564 struct task_group *tg; /* group that "owns" this runqueue */
565
566 #ifdef CONFIG_CFS_BANDWIDTH
567 int runtime_enabled;
568 s64 runtime_remaining;
569
570 u64 throttled_clock;
571 u64 throttled_clock_task;
572 u64 throttled_clock_task_time;
573 int throttled;
574 int throttle_count;
575 struct list_head throttled_list;
576 #endif /* CONFIG_CFS_BANDWIDTH */
577 #endif /* CONFIG_FAIR_GROUP_SCHED */
578 };
579
rt_bandwidth_enabled(void)580 static inline int rt_bandwidth_enabled(void)
581 {
582 return sysctl_sched_rt_runtime >= 0;
583 }
584
585 /* RT IPI pull logic requires IRQ_WORK */
586 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
587 # define HAVE_RT_PUSH_IPI
588 #endif
589
590 /* Real-Time classes' related field in a runqueue: */
591 struct rt_rq {
592 struct rt_prio_array active;
593 unsigned int rt_nr_running;
594 unsigned int rr_nr_running;
595 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
596 struct {
597 int curr; /* highest queued rt task prio */
598 #ifdef CONFIG_SMP
599 int next; /* next highest */
600 #endif
601 } highest_prio;
602 #endif
603 #ifdef CONFIG_SMP
604 unsigned long rt_nr_migratory;
605 unsigned long rt_nr_total;
606 int overloaded;
607 struct plist_head pushable_tasks;
608
609 #endif /* CONFIG_SMP */
610 int rt_queued;
611
612 int rt_throttled;
613 u64 rt_time;
614 u64 rt_runtime;
615 /* Nests inside the rq lock: */
616 raw_spinlock_t rt_runtime_lock;
617
618 #ifdef CONFIG_RT_GROUP_SCHED
619 unsigned long rt_nr_boosted;
620
621 struct rq *rq;
622 struct task_group *tg;
623 #endif
624 };
625
rt_rq_is_runnable(struct rt_rq * rt_rq)626 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
627 {
628 return rt_rq->rt_queued && rt_rq->rt_nr_running;
629 }
630
631 /* Deadline class' related fields in a runqueue */
632 struct dl_rq {
633 /* runqueue is an rbtree, ordered by deadline */
634 struct rb_root_cached root;
635
636 unsigned long dl_nr_running;
637
638 #ifdef CONFIG_SMP
639 /*
640 * Deadline values of the currently executing and the
641 * earliest ready task on this rq. Caching these facilitates
642 * the decision whether or not a ready but not running task
643 * should migrate somewhere else.
644 */
645 struct {
646 u64 curr;
647 u64 next;
648 } earliest_dl;
649
650 unsigned long dl_nr_migratory;
651 int overloaded;
652
653 /*
654 * Tasks on this rq that can be pushed away. They are kept in
655 * an rb-tree, ordered by tasks' deadlines, with caching
656 * of the leftmost (earliest deadline) element.
657 */
658 struct rb_root_cached pushable_dl_tasks_root;
659 #else
660 struct dl_bw dl_bw;
661 #endif
662 /*
663 * "Active utilization" for this runqueue: increased when a
664 * task wakes up (becomes TASK_RUNNING) and decreased when a
665 * task blocks
666 */
667 u64 running_bw;
668
669 /*
670 * Utilization of the tasks "assigned" to this runqueue (including
671 * the tasks that are in runqueue and the tasks that executed on this
672 * CPU and blocked). Increased when a task moves to this runqueue, and
673 * decreased when the task moves away (migrates, changes scheduling
674 * policy, or terminates).
675 * This is needed to compute the "inactive utilization" for the
676 * runqueue (inactive utilization = this_bw - running_bw).
677 */
678 u64 this_bw;
679 u64 extra_bw;
680
681 /*
682 * Inverse of the fraction of CPU utilization that can be reclaimed
683 * by the GRUB algorithm.
684 */
685 u64 bw_ratio;
686 };
687
688 #ifdef CONFIG_FAIR_GROUP_SCHED
689 /* An entity is a task if it doesn't "own" a runqueue */
690 #define entity_is_task(se) (!se->my_q)
691 #else
692 #define entity_is_task(se) 1
693 #endif
694
695 #ifdef CONFIG_SMP
696 /*
697 * XXX we want to get rid of these helpers and use the full load resolution.
698 */
se_weight(struct sched_entity * se)699 static inline long se_weight(struct sched_entity *se)
700 {
701 return scale_load_down(se->load.weight);
702 }
703
se_runnable(struct sched_entity * se)704 static inline long se_runnable(struct sched_entity *se)
705 {
706 return scale_load_down(se->runnable_weight);
707 }
708
sched_asym_prefer(int a,int b)709 static inline bool sched_asym_prefer(int a, int b)
710 {
711 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
712 }
713
714 struct perf_domain {
715 struct em_perf_domain *em_pd;
716 struct perf_domain *next;
717 struct rcu_head rcu;
718 };
719
720 /* Scheduling group status flags */
721 #define SG_OVERLOAD 0x1 /* More than one runnable task on a CPU. */
722 #define SG_OVERUTILIZED 0x2 /* One or more CPUs are over-utilized. */
723
724 /*
725 * We add the notion of a root-domain which will be used to define per-domain
726 * variables. Each exclusive cpuset essentially defines an island domain by
727 * fully partitioning the member CPUs from any other cpuset. Whenever a new
728 * exclusive cpuset is created, we also create and attach a new root-domain
729 * object.
730 *
731 */
732 struct root_domain {
733 atomic_t refcount;
734 atomic_t rto_count;
735 struct rcu_head rcu;
736 cpumask_var_t span;
737 cpumask_var_t online;
738
739 /*
740 * Indicate pullable load on at least one CPU, e.g:
741 * - More than one runnable task
742 * - Running task is misfit
743 */
744 int overload;
745
746 /* Indicate one or more cpus over-utilized (tipping point) */
747 int overutilized;
748
749 /*
750 * The bit corresponding to a CPU gets set here if such CPU has more
751 * than one runnable -deadline task (as it is below for RT tasks).
752 */
753 cpumask_var_t dlo_mask;
754 atomic_t dlo_count;
755 struct dl_bw dl_bw;
756 struct cpudl cpudl;
757
758 #ifdef HAVE_RT_PUSH_IPI
759 /*
760 * For IPI pull requests, loop across the rto_mask.
761 */
762 struct irq_work rto_push_work;
763 raw_spinlock_t rto_lock;
764 /* These are only updated and read within rto_lock */
765 int rto_loop;
766 int rto_cpu;
767 /* These atomics are updated outside of a lock */
768 atomic_t rto_loop_next;
769 atomic_t rto_loop_start;
770 #endif
771 /*
772 * The "RT overload" flag: it gets set if a CPU has more than
773 * one runnable RT task.
774 */
775 cpumask_var_t rto_mask;
776 struct cpupri cpupri;
777
778 unsigned long max_cpu_capacity;
779
780 /*
781 * NULL-terminated list of performance domains intersecting with the
782 * CPUs of the rd. Protected by RCU.
783 */
784 struct perf_domain __rcu *pd;
785 };
786
787 extern void init_defrootdomain(void);
788 extern int sched_init_domains(const struct cpumask *cpu_map);
789 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
790 extern void sched_get_rd(struct root_domain *rd);
791 extern void sched_put_rd(struct root_domain *rd);
792
793 #ifdef HAVE_RT_PUSH_IPI
794 extern void rto_push_irq_work_func(struct irq_work *work);
795 #endif
796 #endif /* CONFIG_SMP */
797
798 #ifdef CONFIG_UCLAMP_TASK
799 /*
800 * struct uclamp_bucket - Utilization clamp bucket
801 * @value: utilization clamp value for tasks on this clamp bucket
802 * @tasks: number of RUNNABLE tasks on this clamp bucket
803 *
804 * Keep track of how many tasks are RUNNABLE for a given utilization
805 * clamp value.
806 */
807 struct uclamp_bucket {
808 unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
809 unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
810 };
811
812 /*
813 * struct uclamp_rq - rq's utilization clamp
814 * @value: currently active clamp values for a rq
815 * @bucket: utilization clamp buckets affecting a rq
816 *
817 * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
818 * A clamp value is affecting a rq when there is at least one task RUNNABLE
819 * (or actually running) with that value.
820 *
821 * There are up to UCLAMP_CNT possible different clamp values, currently there
822 * are only two: minimum utilization and maximum utilization.
823 *
824 * All utilization clamping values are MAX aggregated, since:
825 * - for util_min: we want to run the CPU at least at the max of the minimum
826 * utilization required by its currently RUNNABLE tasks.
827 * - for util_max: we want to allow the CPU to run up to the max of the
828 * maximum utilization allowed by its currently RUNNABLE tasks.
829 *
830 * Since on each system we expect only a limited number of different
831 * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
832 * the metrics required to compute all the per-rq utilization clamp values.
833 */
834 struct uclamp_rq {
835 unsigned int value;
836 struct uclamp_bucket bucket[UCLAMP_BUCKETS];
837 };
838 #endif /* CONFIG_UCLAMP_TASK */
839
840 /*
841 * This is the main, per-CPU runqueue data structure.
842 *
843 * Locking rule: those places that want to lock multiple runqueues
844 * (such as the load balancing or the thread migration code), lock
845 * acquire operations must be ordered by ascending &runqueue.
846 */
847 struct rq {
848 /* runqueue lock: */
849 raw_spinlock_t lock;
850
851 /*
852 * nr_running and cpu_load should be in the same cacheline because
853 * remote CPUs use both these fields when doing load calculation.
854 */
855 unsigned int nr_running;
856 #ifdef CONFIG_NUMA_BALANCING
857 unsigned int nr_numa_running;
858 unsigned int nr_preferred_running;
859 unsigned int numa_migrate_on;
860 #endif
861 #ifdef CONFIG_NO_HZ_COMMON
862 #ifdef CONFIG_SMP
863 unsigned long last_load_update_tick;
864 unsigned long last_blocked_load_update_tick;
865 unsigned int has_blocked_load;
866 #endif /* CONFIG_SMP */
867 unsigned int nohz_tick_stopped;
868 atomic_t nohz_flags;
869 #endif /* CONFIG_NO_HZ_COMMON */
870
871 unsigned long nr_load_updates;
872 u64 nr_switches;
873
874 #ifdef CONFIG_UCLAMP_TASK
875 /* Utilization clamp values based on CPU's RUNNABLE tasks */
876 struct uclamp_rq uclamp[UCLAMP_CNT] ____cacheline_aligned;
877 unsigned int uclamp_flags;
878 #define UCLAMP_FLAG_IDLE 0x01
879 #endif
880
881 struct cfs_rq cfs;
882 struct rt_rq rt;
883 struct dl_rq dl;
884
885 #ifdef CONFIG_FAIR_GROUP_SCHED
886 /* list of leaf cfs_rq on this CPU: */
887 struct list_head leaf_cfs_rq_list;
888 struct list_head *tmp_alone_branch;
889 #endif /* CONFIG_FAIR_GROUP_SCHED */
890
891 /*
892 * This is part of a global counter where only the total sum
893 * over all CPUs matters. A task can increase this counter on
894 * one CPU and if it got migrated afterwards it may decrease
895 * it on another CPU. Always updated under the runqueue lock:
896 */
897 unsigned long nr_uninterruptible;
898
899 struct task_struct *curr;
900 struct task_struct *idle;
901 struct task_struct *stop;
902 unsigned long next_balance;
903 struct mm_struct *prev_mm;
904
905 unsigned int clock_update_flags;
906 u64 clock;
907 /* Ensure that all clocks are in the same cache line */
908 u64 clock_task ____cacheline_aligned;
909 u64 clock_pelt;
910 unsigned long lost_idle_time;
911
912 atomic_t nr_iowait;
913
914 #ifdef CONFIG_MEMBARRIER
915 int membarrier_state;
916 #endif
917
918 #ifdef CONFIG_SMP
919 struct root_domain *rd;
920 struct sched_domain __rcu *sd;
921
922 unsigned long cpu_capacity;
923 unsigned long cpu_capacity_orig;
924
925 struct callback_head *balance_callback;
926
927 unsigned char idle_balance;
928
929 unsigned long misfit_task_load;
930
931 /* For active balancing */
932 int active_balance;
933 int push_cpu;
934 struct cpu_stop_work active_balance_work;
935
936 /* CPU of this runqueue: */
937 int cpu;
938 int online;
939
940 struct list_head cfs_tasks;
941
942 struct sched_avg avg_rt;
943 struct sched_avg avg_dl;
944 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
945 struct sched_avg avg_irq;
946 #endif
947 u64 idle_stamp;
948 u64 avg_idle;
949
950 /* This is used to determine avg_idle's max value */
951 u64 max_idle_balance_cost;
952 #endif
953
954 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
955 u64 prev_irq_time;
956 #endif
957 #ifdef CONFIG_PARAVIRT
958 u64 prev_steal_time;
959 #endif
960 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
961 u64 prev_steal_time_rq;
962 #endif
963
964 /* calc_load related fields */
965 unsigned long calc_load_update;
966 long calc_load_active;
967
968 #ifdef CONFIG_SCHED_HRTICK
969 #ifdef CONFIG_SMP
970 int hrtick_csd_pending;
971 call_single_data_t hrtick_csd;
972 #endif
973 struct hrtimer hrtick_timer;
974 #endif
975
976 #ifdef CONFIG_SCHEDSTATS
977 /* latency stats */
978 struct sched_info rq_sched_info;
979 unsigned long long rq_cpu_time;
980 /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
981
982 /* sys_sched_yield() stats */
983 unsigned int yld_count;
984
985 /* schedule() stats */
986 unsigned int sched_count;
987 unsigned int sched_goidle;
988
989 /* try_to_wake_up() stats */
990 unsigned int ttwu_count;
991 unsigned int ttwu_local;
992 #endif
993
994 #ifdef CONFIG_SMP
995 struct llist_head wake_list;
996 #endif
997
998 #ifdef CONFIG_CPU_IDLE
999 /* Must be inspected within a rcu lock section */
1000 struct cpuidle_state *idle_state;
1001 #endif
1002 };
1003
1004 #ifdef CONFIG_FAIR_GROUP_SCHED
1005
1006 /* CPU runqueue to which this cfs_rq is attached */
rq_of(struct cfs_rq * cfs_rq)1007 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1008 {
1009 return cfs_rq->rq;
1010 }
1011
1012 #else
1013
rq_of(struct cfs_rq * cfs_rq)1014 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1015 {
1016 return container_of(cfs_rq, struct rq, cfs);
1017 }
1018 #endif
1019
cpu_of(struct rq * rq)1020 static inline int cpu_of(struct rq *rq)
1021 {
1022 #ifdef CONFIG_SMP
1023 return rq->cpu;
1024 #else
1025 return 0;
1026 #endif
1027 }
1028
1029
1030 #ifdef CONFIG_SCHED_SMT
1031 extern void __update_idle_core(struct rq *rq);
1032
update_idle_core(struct rq * rq)1033 static inline void update_idle_core(struct rq *rq)
1034 {
1035 if (static_branch_unlikely(&sched_smt_present))
1036 __update_idle_core(rq);
1037 }
1038
1039 #else
update_idle_core(struct rq * rq)1040 static inline void update_idle_core(struct rq *rq) { }
1041 #endif
1042
1043 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1044
1045 #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
1046 #define this_rq() this_cpu_ptr(&runqueues)
1047 #define task_rq(p) cpu_rq(task_cpu(p))
1048 #define cpu_curr(cpu) (cpu_rq(cpu)->curr)
1049 #define raw_rq() raw_cpu_ptr(&runqueues)
1050
1051 extern void update_rq_clock(struct rq *rq);
1052
__rq_clock_broken(struct rq * rq)1053 static inline u64 __rq_clock_broken(struct rq *rq)
1054 {
1055 return READ_ONCE(rq->clock);
1056 }
1057
1058 /*
1059 * rq::clock_update_flags bits
1060 *
1061 * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1062 * call to __schedule(). This is an optimisation to avoid
1063 * neighbouring rq clock updates.
1064 *
1065 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1066 * in effect and calls to update_rq_clock() are being ignored.
1067 *
1068 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1069 * made to update_rq_clock() since the last time rq::lock was pinned.
1070 *
1071 * If inside of __schedule(), clock_update_flags will have been
1072 * shifted left (a left shift is a cheap operation for the fast path
1073 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1074 *
1075 * if (rq-clock_update_flags >= RQCF_UPDATED)
1076 *
1077 * to check if %RQCF_UPADTED is set. It'll never be shifted more than
1078 * one position though, because the next rq_unpin_lock() will shift it
1079 * back.
1080 */
1081 #define RQCF_REQ_SKIP 0x01
1082 #define RQCF_ACT_SKIP 0x02
1083 #define RQCF_UPDATED 0x04
1084
assert_clock_updated(struct rq * rq)1085 static inline void assert_clock_updated(struct rq *rq)
1086 {
1087 /*
1088 * The only reason for not seeing a clock update since the
1089 * last rq_pin_lock() is if we're currently skipping updates.
1090 */
1091 SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
1092 }
1093
rq_clock(struct rq * rq)1094 static inline u64 rq_clock(struct rq *rq)
1095 {
1096 lockdep_assert_held(&rq->lock);
1097 assert_clock_updated(rq);
1098
1099 return rq->clock;
1100 }
1101
rq_clock_task(struct rq * rq)1102 static inline u64 rq_clock_task(struct rq *rq)
1103 {
1104 lockdep_assert_held(&rq->lock);
1105 assert_clock_updated(rq);
1106
1107 return rq->clock_task;
1108 }
1109
rq_clock_skip_update(struct rq * rq)1110 static inline void rq_clock_skip_update(struct rq *rq)
1111 {
1112 lockdep_assert_held(&rq->lock);
1113 rq->clock_update_flags |= RQCF_REQ_SKIP;
1114 }
1115
1116 /*
1117 * See rt task throttling, which is the only time a skip
1118 * request is cancelled.
1119 */
rq_clock_cancel_skipupdate(struct rq * rq)1120 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1121 {
1122 lockdep_assert_held(&rq->lock);
1123 rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1124 }
1125
1126 struct rq_flags {
1127 unsigned long flags;
1128 struct pin_cookie cookie;
1129 #ifdef CONFIG_SCHED_DEBUG
1130 /*
1131 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1132 * current pin context is stashed here in case it needs to be
1133 * restored in rq_repin_lock().
1134 */
1135 unsigned int clock_update_flags;
1136 #endif
1137 };
1138
rq_pin_lock(struct rq * rq,struct rq_flags * rf)1139 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1140 {
1141 rf->cookie = lockdep_pin_lock(&rq->lock);
1142
1143 #ifdef CONFIG_SCHED_DEBUG
1144 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1145 rf->clock_update_flags = 0;
1146 #endif
1147 }
1148
rq_unpin_lock(struct rq * rq,struct rq_flags * rf)1149 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1150 {
1151 #ifdef CONFIG_SCHED_DEBUG
1152 if (rq->clock_update_flags > RQCF_ACT_SKIP)
1153 rf->clock_update_flags = RQCF_UPDATED;
1154 #endif
1155
1156 lockdep_unpin_lock(&rq->lock, rf->cookie);
1157 }
1158
rq_repin_lock(struct rq * rq,struct rq_flags * rf)1159 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1160 {
1161 lockdep_repin_lock(&rq->lock, rf->cookie);
1162
1163 #ifdef CONFIG_SCHED_DEBUG
1164 /*
1165 * Restore the value we stashed in @rf for this pin context.
1166 */
1167 rq->clock_update_flags |= rf->clock_update_flags;
1168 #endif
1169 }
1170
1171 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1172 __acquires(rq->lock);
1173
1174 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1175 __acquires(p->pi_lock)
1176 __acquires(rq->lock);
1177
__task_rq_unlock(struct rq * rq,struct rq_flags * rf)1178 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1179 __releases(rq->lock)
1180 {
1181 rq_unpin_lock(rq, rf);
1182 raw_spin_unlock(&rq->lock);
1183 }
1184
1185 static inline void
task_rq_unlock(struct rq * rq,struct task_struct * p,struct rq_flags * rf)1186 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1187 __releases(rq->lock)
1188 __releases(p->pi_lock)
1189 {
1190 rq_unpin_lock(rq, rf);
1191 raw_spin_unlock(&rq->lock);
1192 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1193 }
1194
1195 static inline void
rq_lock_irqsave(struct rq * rq,struct rq_flags * rf)1196 rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1197 __acquires(rq->lock)
1198 {
1199 raw_spin_lock_irqsave(&rq->lock, rf->flags);
1200 rq_pin_lock(rq, rf);
1201 }
1202
1203 static inline void
rq_lock_irq(struct rq * rq,struct rq_flags * rf)1204 rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1205 __acquires(rq->lock)
1206 {
1207 raw_spin_lock_irq(&rq->lock);
1208 rq_pin_lock(rq, rf);
1209 }
1210
1211 static inline void
rq_lock(struct rq * rq,struct rq_flags * rf)1212 rq_lock(struct rq *rq, struct rq_flags *rf)
1213 __acquires(rq->lock)
1214 {
1215 raw_spin_lock(&rq->lock);
1216 rq_pin_lock(rq, rf);
1217 }
1218
1219 static inline void
rq_relock(struct rq * rq,struct rq_flags * rf)1220 rq_relock(struct rq *rq, struct rq_flags *rf)
1221 __acquires(rq->lock)
1222 {
1223 raw_spin_lock(&rq->lock);
1224 rq_repin_lock(rq, rf);
1225 }
1226
1227 static inline void
rq_unlock_irqrestore(struct rq * rq,struct rq_flags * rf)1228 rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1229 __releases(rq->lock)
1230 {
1231 rq_unpin_lock(rq, rf);
1232 raw_spin_unlock_irqrestore(&rq->lock, rf->flags);
1233 }
1234
1235 static inline void
rq_unlock_irq(struct rq * rq,struct rq_flags * rf)1236 rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1237 __releases(rq->lock)
1238 {
1239 rq_unpin_lock(rq, rf);
1240 raw_spin_unlock_irq(&rq->lock);
1241 }
1242
1243 static inline void
rq_unlock(struct rq * rq,struct rq_flags * rf)1244 rq_unlock(struct rq *rq, struct rq_flags *rf)
1245 __releases(rq->lock)
1246 {
1247 rq_unpin_lock(rq, rf);
1248 raw_spin_unlock(&rq->lock);
1249 }
1250
1251 static inline struct rq *
this_rq_lock_irq(struct rq_flags * rf)1252 this_rq_lock_irq(struct rq_flags *rf)
1253 __acquires(rq->lock)
1254 {
1255 struct rq *rq;
1256
1257 local_irq_disable();
1258 rq = this_rq();
1259 rq_lock(rq, rf);
1260 return rq;
1261 }
1262
1263 #ifdef CONFIG_NUMA
1264 enum numa_topology_type {
1265 NUMA_DIRECT,
1266 NUMA_GLUELESS_MESH,
1267 NUMA_BACKPLANE,
1268 };
1269 extern enum numa_topology_type sched_numa_topology_type;
1270 extern int sched_max_numa_distance;
1271 extern bool find_numa_distance(int distance);
1272 extern void sched_init_numa(void);
1273 extern void sched_domains_numa_masks_set(unsigned int cpu);
1274 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1275 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1276 #else
sched_init_numa(void)1277 static inline void sched_init_numa(void) { }
sched_domains_numa_masks_set(unsigned int cpu)1278 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
sched_domains_numa_masks_clear(unsigned int cpu)1279 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
sched_numa_find_closest(const struct cpumask * cpus,int cpu)1280 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1281 {
1282 return nr_cpu_ids;
1283 }
1284 #endif
1285
1286 #ifdef CONFIG_NUMA_BALANCING
1287 /* The regions in numa_faults array from task_struct */
1288 enum numa_faults_stats {
1289 NUMA_MEM = 0,
1290 NUMA_CPU,
1291 NUMA_MEMBUF,
1292 NUMA_CPUBUF
1293 };
1294 extern void sched_setnuma(struct task_struct *p, int node);
1295 extern int migrate_task_to(struct task_struct *p, int cpu);
1296 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1297 int cpu, int scpu);
1298 extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1299 #else
1300 static inline void
init_numa_balancing(unsigned long clone_flags,struct task_struct * p)1301 init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1302 {
1303 }
1304 #endif /* CONFIG_NUMA_BALANCING */
1305
1306 #ifdef CONFIG_SMP
1307
1308 static inline void
queue_balance_callback(struct rq * rq,struct callback_head * head,void (* func)(struct rq * rq))1309 queue_balance_callback(struct rq *rq,
1310 struct callback_head *head,
1311 void (*func)(struct rq *rq))
1312 {
1313 lockdep_assert_held(&rq->lock);
1314
1315 if (unlikely(head->next))
1316 return;
1317
1318 head->func = (void (*)(struct callback_head *))func;
1319 head->next = rq->balance_callback;
1320 rq->balance_callback = head;
1321 }
1322
1323 extern void sched_ttwu_pending(void);
1324
1325 #define rcu_dereference_check_sched_domain(p) \
1326 rcu_dereference_check((p), \
1327 lockdep_is_held(&sched_domains_mutex))
1328
1329 /*
1330 * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1331 * See destroy_sched_domains: call_rcu for details.
1332 *
1333 * The domain tree of any CPU may only be accessed from within
1334 * preempt-disabled sections.
1335 */
1336 #define for_each_domain(cpu, __sd) \
1337 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1338 __sd; __sd = __sd->parent)
1339
1340 #define for_each_lower_domain(sd) for (; sd; sd = sd->child)
1341
1342 /**
1343 * highest_flag_domain - Return highest sched_domain containing flag.
1344 * @cpu: The CPU whose highest level of sched domain is to
1345 * be returned.
1346 * @flag: The flag to check for the highest sched_domain
1347 * for the given CPU.
1348 *
1349 * Returns the highest sched_domain of a CPU which contains the given flag.
1350 */
highest_flag_domain(int cpu,int flag)1351 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1352 {
1353 struct sched_domain *sd, *hsd = NULL;
1354
1355 for_each_domain(cpu, sd) {
1356 if (!(sd->flags & flag))
1357 break;
1358 hsd = sd;
1359 }
1360
1361 return hsd;
1362 }
1363
lowest_flag_domain(int cpu,int flag)1364 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1365 {
1366 struct sched_domain *sd;
1367
1368 for_each_domain(cpu, sd) {
1369 if (sd->flags & flag)
1370 break;
1371 }
1372
1373 return sd;
1374 }
1375
1376 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
1377 DECLARE_PER_CPU(int, sd_llc_size);
1378 DECLARE_PER_CPU(int, sd_llc_id);
1379 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
1380 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
1381 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
1382 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
1383 extern struct static_key_false sched_asym_cpucapacity;
1384
1385 struct sched_group_capacity {
1386 atomic_t ref;
1387 /*
1388 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
1389 * for a single CPU.
1390 */
1391 unsigned long capacity;
1392 unsigned long min_capacity; /* Min per-CPU capacity in group */
1393 unsigned long max_capacity; /* Max per-CPU capacity in group */
1394 unsigned long next_update;
1395 int imbalance; /* XXX unrelated to capacity but shared group state */
1396
1397 #ifdef CONFIG_SCHED_DEBUG
1398 int id;
1399 #endif
1400
1401 unsigned long cpumask[0]; /* Balance mask */
1402 };
1403
1404 struct sched_group {
1405 struct sched_group *next; /* Must be a circular list */
1406 atomic_t ref;
1407
1408 unsigned int group_weight;
1409 struct sched_group_capacity *sgc;
1410 int asym_prefer_cpu; /* CPU of highest priority in group */
1411
1412 /*
1413 * The CPUs this group covers.
1414 *
1415 * NOTE: this field is variable length. (Allocated dynamically
1416 * by attaching extra space to the end of the structure,
1417 * depending on how many CPUs the kernel has booted up with)
1418 */
1419 unsigned long cpumask[0];
1420 };
1421
sched_group_span(struct sched_group * sg)1422 static inline struct cpumask *sched_group_span(struct sched_group *sg)
1423 {
1424 return to_cpumask(sg->cpumask);
1425 }
1426
1427 /*
1428 * See build_balance_mask().
1429 */
group_balance_mask(struct sched_group * sg)1430 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
1431 {
1432 return to_cpumask(sg->sgc->cpumask);
1433 }
1434
1435 /**
1436 * group_first_cpu - Returns the first CPU in the cpumask of a sched_group.
1437 * @group: The group whose first CPU is to be returned.
1438 */
group_first_cpu(struct sched_group * group)1439 static inline unsigned int group_first_cpu(struct sched_group *group)
1440 {
1441 return cpumask_first(sched_group_span(group));
1442 }
1443
1444 extern int group_balance_cpu(struct sched_group *sg);
1445
1446 #if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
1447 void register_sched_domain_sysctl(void);
1448 void dirty_sched_domain_sysctl(int cpu);
1449 void unregister_sched_domain_sysctl(void);
1450 #else
register_sched_domain_sysctl(void)1451 static inline void register_sched_domain_sysctl(void)
1452 {
1453 }
dirty_sched_domain_sysctl(int cpu)1454 static inline void dirty_sched_domain_sysctl(int cpu)
1455 {
1456 }
unregister_sched_domain_sysctl(void)1457 static inline void unregister_sched_domain_sysctl(void)
1458 {
1459 }
1460 #endif
1461
1462 extern int newidle_balance(struct rq *this_rq, struct rq_flags *rf);
1463
1464 #else
1465
sched_ttwu_pending(void)1466 static inline void sched_ttwu_pending(void) { }
1467
newidle_balance(struct rq * this_rq,struct rq_flags * rf)1468 static inline int newidle_balance(struct rq *this_rq, struct rq_flags *rf) { return 0; }
1469
1470 #endif /* CONFIG_SMP */
1471
1472 #include "stats.h"
1473 #include "autogroup.h"
1474
1475 #ifdef CONFIG_CGROUP_SCHED
1476
1477 /*
1478 * Return the group to which this tasks belongs.
1479 *
1480 * We cannot use task_css() and friends because the cgroup subsystem
1481 * changes that value before the cgroup_subsys::attach() method is called,
1482 * therefore we cannot pin it and might observe the wrong value.
1483 *
1484 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
1485 * core changes this before calling sched_move_task().
1486 *
1487 * Instead we use a 'copy' which is updated from sched_move_task() while
1488 * holding both task_struct::pi_lock and rq::lock.
1489 */
task_group(struct task_struct * p)1490 static inline struct task_group *task_group(struct task_struct *p)
1491 {
1492 return p->sched_task_group;
1493 }
1494
1495 /* 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)1496 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
1497 {
1498 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
1499 struct task_group *tg = task_group(p);
1500 #endif
1501
1502 #ifdef CONFIG_FAIR_GROUP_SCHED
1503 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
1504 p->se.cfs_rq = tg->cfs_rq[cpu];
1505 p->se.parent = tg->se[cpu];
1506 #endif
1507
1508 #ifdef CONFIG_RT_GROUP_SCHED
1509 p->rt.rt_rq = tg->rt_rq[cpu];
1510 p->rt.parent = tg->rt_se[cpu];
1511 #endif
1512 }
1513
1514 #else /* CONFIG_CGROUP_SCHED */
1515
set_task_rq(struct task_struct * p,unsigned int cpu)1516 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
task_group(struct task_struct * p)1517 static inline struct task_group *task_group(struct task_struct *p)
1518 {
1519 return NULL;
1520 }
1521
1522 #endif /* CONFIG_CGROUP_SCHED */
1523
__set_task_cpu(struct task_struct * p,unsigned int cpu)1524 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
1525 {
1526 set_task_rq(p, cpu);
1527 #ifdef CONFIG_SMP
1528 /*
1529 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
1530 * successfully executed on another CPU. We must ensure that updates of
1531 * per-task data have been completed by this moment.
1532 */
1533 smp_wmb();
1534 #ifdef CONFIG_THREAD_INFO_IN_TASK
1535 WRITE_ONCE(p->cpu, cpu);
1536 #else
1537 WRITE_ONCE(task_thread_info(p)->cpu, cpu);
1538 #endif
1539 p->wake_cpu = cpu;
1540 #endif
1541 }
1542
1543 /*
1544 * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
1545 */
1546 #ifdef CONFIG_SCHED_DEBUG
1547 # include <linux/static_key.h>
1548 # define const_debug __read_mostly
1549 #else
1550 # define const_debug const
1551 #endif
1552
1553 #define SCHED_FEAT(name, enabled) \
1554 __SCHED_FEAT_##name ,
1555
1556 enum {
1557 #include "features.h"
1558 __SCHED_FEAT_NR,
1559 };
1560
1561 #undef SCHED_FEAT
1562
1563 #if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_JUMP_LABEL)
1564
1565 /*
1566 * To support run-time toggling of sched features, all the translation units
1567 * (but core.c) reference the sysctl_sched_features defined in core.c.
1568 */
1569 extern const_debug unsigned int sysctl_sched_features;
1570
1571 #define SCHED_FEAT(name, enabled) \
1572 static __always_inline bool static_branch_##name(struct static_key *key) \
1573 { \
1574 return static_key_##enabled(key); \
1575 }
1576
1577 #include "features.h"
1578 #undef SCHED_FEAT
1579
1580 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
1581 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
1582
1583 #else /* !(SCHED_DEBUG && CONFIG_JUMP_LABEL) */
1584
1585 /*
1586 * Each translation unit has its own copy of sysctl_sched_features to allow
1587 * constants propagation at compile time and compiler optimization based on
1588 * features default.
1589 */
1590 #define SCHED_FEAT(name, enabled) \
1591 (1UL << __SCHED_FEAT_##name) * enabled |
1592 static const_debug __maybe_unused unsigned int sysctl_sched_features =
1593 #include "features.h"
1594 0;
1595 #undef SCHED_FEAT
1596
1597 #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1598
1599 #endif /* SCHED_DEBUG && CONFIG_JUMP_LABEL */
1600
1601 extern struct static_key_false sched_numa_balancing;
1602 extern struct static_key_false sched_schedstats;
1603
global_rt_period(void)1604 static inline u64 global_rt_period(void)
1605 {
1606 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
1607 }
1608
global_rt_runtime(void)1609 static inline u64 global_rt_runtime(void)
1610 {
1611 if (sysctl_sched_rt_runtime < 0)
1612 return RUNTIME_INF;
1613
1614 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
1615 }
1616
task_current(struct rq * rq,struct task_struct * p)1617 static inline int task_current(struct rq *rq, struct task_struct *p)
1618 {
1619 return rq->curr == p;
1620 }
1621
task_running(struct rq * rq,struct task_struct * p)1622 static inline int task_running(struct rq *rq, struct task_struct *p)
1623 {
1624 #ifdef CONFIG_SMP
1625 return p->on_cpu;
1626 #else
1627 return task_current(rq, p);
1628 #endif
1629 }
1630
task_on_rq_queued(struct task_struct * p)1631 static inline int task_on_rq_queued(struct task_struct *p)
1632 {
1633 return p->on_rq == TASK_ON_RQ_QUEUED;
1634 }
1635
task_on_rq_migrating(struct task_struct * p)1636 static inline int task_on_rq_migrating(struct task_struct *p)
1637 {
1638 return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
1639 }
1640
1641 /*
1642 * wake flags
1643 */
1644 #define WF_SYNC 0x01 /* Waker goes to sleep after wakeup */
1645 #define WF_FORK 0x02 /* Child wakeup after fork */
1646 #define WF_MIGRATED 0x4 /* Internal use, task got migrated */
1647
1648 /*
1649 * To aid in avoiding the subversion of "niceness" due to uneven distribution
1650 * of tasks with abnormal "nice" values across CPUs the contribution that
1651 * each task makes to its run queue's load is weighted according to its
1652 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
1653 * scaled version of the new time slice allocation that they receive on time
1654 * slice expiry etc.
1655 */
1656
1657 #define WEIGHT_IDLEPRIO 3
1658 #define WMULT_IDLEPRIO 1431655765
1659
1660 extern const int sched_prio_to_weight[40];
1661 extern const u32 sched_prio_to_wmult[40];
1662
1663 /*
1664 * {de,en}queue flags:
1665 *
1666 * DEQUEUE_SLEEP - task is no longer runnable
1667 * ENQUEUE_WAKEUP - task just became runnable
1668 *
1669 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
1670 * are in a known state which allows modification. Such pairs
1671 * should preserve as much state as possible.
1672 *
1673 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
1674 * in the runqueue.
1675 *
1676 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified)
1677 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
1678 * ENQUEUE_MIGRATED - the task was migrated during wakeup
1679 *
1680 */
1681
1682 #define DEQUEUE_SLEEP 0x01
1683 #define DEQUEUE_SAVE 0x02 /* Matches ENQUEUE_RESTORE */
1684 #define DEQUEUE_MOVE 0x04 /* Matches ENQUEUE_MOVE */
1685 #define DEQUEUE_NOCLOCK 0x08 /* Matches ENQUEUE_NOCLOCK */
1686
1687 #define ENQUEUE_WAKEUP 0x01
1688 #define ENQUEUE_RESTORE 0x02
1689 #define ENQUEUE_MOVE 0x04
1690 #define ENQUEUE_NOCLOCK 0x08
1691
1692 #define ENQUEUE_HEAD 0x10
1693 #define ENQUEUE_REPLENISH 0x20
1694 #ifdef CONFIG_SMP
1695 #define ENQUEUE_MIGRATED 0x40
1696 #else
1697 #define ENQUEUE_MIGRATED 0x00
1698 #endif
1699
1700 #define RETRY_TASK ((void *)-1UL)
1701
1702 struct sched_class {
1703 const struct sched_class *next;
1704
1705 #ifdef CONFIG_UCLAMP_TASK
1706 int uclamp_enabled;
1707 #endif
1708
1709 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1710 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1711 void (*yield_task) (struct rq *rq);
1712 bool (*yield_to_task)(struct rq *rq, struct task_struct *p, bool preempt);
1713
1714 void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags);
1715
1716 /*
1717 * Both @prev and @rf are optional and may be NULL, in which case the
1718 * caller must already have invoked put_prev_task(rq, prev, rf).
1719 *
1720 * Otherwise it is the responsibility of the pick_next_task() to call
1721 * put_prev_task() on the @prev task or something equivalent, IFF it
1722 * returns a next task.
1723 *
1724 * In that case (@rf != NULL) it may return RETRY_TASK when it finds a
1725 * higher prio class has runnable tasks.
1726 */
1727 struct task_struct * (*pick_next_task)(struct rq *rq,
1728 struct task_struct *prev,
1729 struct rq_flags *rf);
1730 void (*put_prev_task)(struct rq *rq, struct task_struct *p);
1731 void (*set_next_task)(struct rq *rq, struct task_struct *p);
1732
1733 #ifdef CONFIG_SMP
1734 int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
1735 int (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
1736 void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
1737
1738 void (*task_woken)(struct rq *this_rq, struct task_struct *task);
1739
1740 void (*set_cpus_allowed)(struct task_struct *p,
1741 const struct cpumask *newmask);
1742
1743 void (*rq_online)(struct rq *rq);
1744 void (*rq_offline)(struct rq *rq);
1745 #endif
1746
1747 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
1748 void (*task_fork)(struct task_struct *p);
1749 void (*task_dead)(struct task_struct *p);
1750
1751 /*
1752 * The switched_from() call is allowed to drop rq->lock, therefore we
1753 * cannot assume the switched_from/switched_to pair is serliazed by
1754 * rq->lock. They are however serialized by p->pi_lock.
1755 */
1756 void (*switched_from)(struct rq *this_rq, struct task_struct *task);
1757 void (*switched_to) (struct rq *this_rq, struct task_struct *task);
1758 void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1759 int oldprio);
1760
1761 unsigned int (*get_rr_interval)(struct rq *rq,
1762 struct task_struct *task);
1763
1764 void (*update_curr)(struct rq *rq);
1765
1766 #define TASK_SET_GROUP 0
1767 #define TASK_MOVE_GROUP 1
1768
1769 #ifdef CONFIG_FAIR_GROUP_SCHED
1770 void (*task_change_group)(struct task_struct *p, int type);
1771 #endif
1772 };
1773
put_prev_task(struct rq * rq,struct task_struct * prev)1774 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
1775 {
1776 WARN_ON_ONCE(rq->curr != prev);
1777 prev->sched_class->put_prev_task(rq, prev);
1778 }
1779
set_next_task(struct rq * rq,struct task_struct * next)1780 static inline void set_next_task(struct rq *rq, struct task_struct *next)
1781 {
1782 WARN_ON_ONCE(rq->curr != next);
1783 next->sched_class->set_next_task(rq, next);
1784 }
1785
1786 #ifdef CONFIG_SMP
1787 #define sched_class_highest (&stop_sched_class)
1788 #else
1789 #define sched_class_highest (&dl_sched_class)
1790 #endif
1791
1792 #define for_class_range(class, _from, _to) \
1793 for (class = (_from); class != (_to); class = class->next)
1794
1795 #define for_each_class(class) \
1796 for_class_range(class, sched_class_highest, NULL)
1797
1798 extern const struct sched_class stop_sched_class;
1799 extern const struct sched_class dl_sched_class;
1800 extern const struct sched_class rt_sched_class;
1801 extern const struct sched_class fair_sched_class;
1802 extern const struct sched_class idle_sched_class;
1803
sched_stop_runnable(struct rq * rq)1804 static inline bool sched_stop_runnable(struct rq *rq)
1805 {
1806 return rq->stop && task_on_rq_queued(rq->stop);
1807 }
1808
sched_dl_runnable(struct rq * rq)1809 static inline bool sched_dl_runnable(struct rq *rq)
1810 {
1811 return rq->dl.dl_nr_running > 0;
1812 }
1813
sched_rt_runnable(struct rq * rq)1814 static inline bool sched_rt_runnable(struct rq *rq)
1815 {
1816 return rq->rt.rt_queued > 0;
1817 }
1818
sched_fair_runnable(struct rq * rq)1819 static inline bool sched_fair_runnable(struct rq *rq)
1820 {
1821 return rq->cfs.nr_running > 0;
1822 }
1823
1824 #ifdef CONFIG_SMP
1825
1826 extern void update_group_capacity(struct sched_domain *sd, int cpu);
1827
1828 extern void trigger_load_balance(struct rq *rq);
1829
1830 extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask);
1831
1832 #endif
1833
1834 #ifdef CONFIG_CPU_IDLE
idle_set_state(struct rq * rq,struct cpuidle_state * idle_state)1835 static inline void idle_set_state(struct rq *rq,
1836 struct cpuidle_state *idle_state)
1837 {
1838 rq->idle_state = idle_state;
1839 }
1840
idle_get_state(struct rq * rq)1841 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1842 {
1843 SCHED_WARN_ON(!rcu_read_lock_held());
1844
1845 return rq->idle_state;
1846 }
1847 #else
idle_set_state(struct rq * rq,struct cpuidle_state * idle_state)1848 static inline void idle_set_state(struct rq *rq,
1849 struct cpuidle_state *idle_state)
1850 {
1851 }
1852
idle_get_state(struct rq * rq)1853 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1854 {
1855 return NULL;
1856 }
1857 #endif
1858
1859 extern void schedule_idle(void);
1860
1861 extern void sysrq_sched_debug_show(void);
1862 extern void sched_init_granularity(void);
1863 extern void update_max_interval(void);
1864
1865 extern void init_sched_dl_class(void);
1866 extern void init_sched_rt_class(void);
1867 extern void init_sched_fair_class(void);
1868
1869 extern void reweight_task(struct task_struct *p, int prio);
1870
1871 extern void resched_curr(struct rq *rq);
1872 extern void resched_cpu(int cpu);
1873
1874 extern struct rt_bandwidth def_rt_bandwidth;
1875 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
1876
1877 extern struct dl_bandwidth def_dl_bandwidth;
1878 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
1879 extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
1880 extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se);
1881 extern void init_dl_rq_bw_ratio(struct dl_rq *dl_rq);
1882
1883 #define BW_SHIFT 20
1884 #define BW_UNIT (1 << BW_SHIFT)
1885 #define RATIO_SHIFT 8
1886 unsigned long to_ratio(u64 period, u64 runtime);
1887
1888 extern void init_entity_runnable_average(struct sched_entity *se);
1889 extern void post_init_entity_util_avg(struct task_struct *p);
1890
1891 #ifdef CONFIG_NO_HZ_FULL
1892 extern bool sched_can_stop_tick(struct rq *rq);
1893 extern int __init sched_tick_offload_init(void);
1894
1895 /*
1896 * Tick may be needed by tasks in the runqueue depending on their policy and
1897 * requirements. If tick is needed, lets send the target an IPI to kick it out of
1898 * nohz mode if necessary.
1899 */
sched_update_tick_dependency(struct rq * rq)1900 static inline void sched_update_tick_dependency(struct rq *rq)
1901 {
1902 int cpu;
1903
1904 if (!tick_nohz_full_enabled())
1905 return;
1906
1907 cpu = cpu_of(rq);
1908
1909 if (!tick_nohz_full_cpu(cpu))
1910 return;
1911
1912 if (sched_can_stop_tick(rq))
1913 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
1914 else
1915 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
1916 }
1917 #else
sched_tick_offload_init(void)1918 static inline int sched_tick_offload_init(void) { return 0; }
sched_update_tick_dependency(struct rq * rq)1919 static inline void sched_update_tick_dependency(struct rq *rq) { }
1920 #endif
1921
add_nr_running(struct rq * rq,unsigned count)1922 static inline void add_nr_running(struct rq *rq, unsigned count)
1923 {
1924 unsigned prev_nr = rq->nr_running;
1925
1926 rq->nr_running = prev_nr + count;
1927
1928 #ifdef CONFIG_SMP
1929 if (prev_nr < 2 && rq->nr_running >= 2) {
1930 if (!READ_ONCE(rq->rd->overload))
1931 WRITE_ONCE(rq->rd->overload, 1);
1932 }
1933 #endif
1934
1935 sched_update_tick_dependency(rq);
1936 }
1937
sub_nr_running(struct rq * rq,unsigned count)1938 static inline void sub_nr_running(struct rq *rq, unsigned count)
1939 {
1940 rq->nr_running -= count;
1941 /* Check if we still need preemption */
1942 sched_update_tick_dependency(rq);
1943 }
1944
1945 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
1946 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
1947
1948 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
1949
1950 extern const_debug unsigned int sysctl_sched_nr_migrate;
1951 extern const_debug unsigned int sysctl_sched_migration_cost;
1952
1953 #ifdef CONFIG_SCHED_HRTICK
1954
1955 /*
1956 * Use hrtick when:
1957 * - enabled by features
1958 * - hrtimer is actually high res
1959 */
hrtick_enabled(struct rq * rq)1960 static inline int hrtick_enabled(struct rq *rq)
1961 {
1962 if (!sched_feat(HRTICK))
1963 return 0;
1964 if (!cpu_active(cpu_of(rq)))
1965 return 0;
1966 return hrtimer_is_hres_active(&rq->hrtick_timer);
1967 }
1968
1969 void hrtick_start(struct rq *rq, u64 delay);
1970
1971 #else
1972
hrtick_enabled(struct rq * rq)1973 static inline int hrtick_enabled(struct rq *rq)
1974 {
1975 return 0;
1976 }
1977
1978 #endif /* CONFIG_SCHED_HRTICK */
1979
1980 #ifndef arch_scale_freq_capacity
1981 static __always_inline
arch_scale_freq_capacity(int cpu)1982 unsigned long arch_scale_freq_capacity(int cpu)
1983 {
1984 return SCHED_CAPACITY_SCALE;
1985 }
1986 #endif
1987
1988 #ifdef CONFIG_SMP
1989 #ifdef CONFIG_PREEMPTION
1990
1991 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2);
1992
1993 /*
1994 * fair double_lock_balance: Safely acquires both rq->locks in a fair
1995 * way at the expense of forcing extra atomic operations in all
1996 * invocations. This assures that the double_lock is acquired using the
1997 * same underlying policy as the spinlock_t on this architecture, which
1998 * reduces latency compared to the unfair variant below. However, it
1999 * also adds more overhead and therefore may reduce throughput.
2000 */
_double_lock_balance(struct rq * this_rq,struct rq * busiest)2001 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2002 __releases(this_rq->lock)
2003 __acquires(busiest->lock)
2004 __acquires(this_rq->lock)
2005 {
2006 raw_spin_unlock(&this_rq->lock);
2007 double_rq_lock(this_rq, busiest);
2008
2009 return 1;
2010 }
2011
2012 #else
2013 /*
2014 * Unfair double_lock_balance: Optimizes throughput at the expense of
2015 * latency by eliminating extra atomic operations when the locks are
2016 * already in proper order on entry. This favors lower CPU-ids and will
2017 * grant the double lock to lower CPUs over higher ids under contention,
2018 * regardless of entry order into the function.
2019 */
_double_lock_balance(struct rq * this_rq,struct rq * busiest)2020 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2021 __releases(this_rq->lock)
2022 __acquires(busiest->lock)
2023 __acquires(this_rq->lock)
2024 {
2025 int ret = 0;
2026
2027 if (unlikely(!raw_spin_trylock(&busiest->lock))) {
2028 if (busiest < this_rq) {
2029 raw_spin_unlock(&this_rq->lock);
2030 raw_spin_lock(&busiest->lock);
2031 raw_spin_lock_nested(&this_rq->lock,
2032 SINGLE_DEPTH_NESTING);
2033 ret = 1;
2034 } else
2035 raw_spin_lock_nested(&busiest->lock,
2036 SINGLE_DEPTH_NESTING);
2037 }
2038 return ret;
2039 }
2040
2041 #endif /* CONFIG_PREEMPTION */
2042
2043 /*
2044 * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
2045 */
double_lock_balance(struct rq * this_rq,struct rq * busiest)2046 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
2047 {
2048 if (unlikely(!irqs_disabled())) {
2049 /* printk() doesn't work well under rq->lock */
2050 raw_spin_unlock(&this_rq->lock);
2051 BUG_ON(1);
2052 }
2053
2054 return _double_lock_balance(this_rq, busiest);
2055 }
2056
double_unlock_balance(struct rq * this_rq,struct rq * busiest)2057 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
2058 __releases(busiest->lock)
2059 {
2060 raw_spin_unlock(&busiest->lock);
2061 lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
2062 }
2063
double_lock(spinlock_t * l1,spinlock_t * l2)2064 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
2065 {
2066 if (l1 > l2)
2067 swap(l1, l2);
2068
2069 spin_lock(l1);
2070 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2071 }
2072
double_lock_irq(spinlock_t * l1,spinlock_t * l2)2073 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
2074 {
2075 if (l1 > l2)
2076 swap(l1, l2);
2077
2078 spin_lock_irq(l1);
2079 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2080 }
2081
double_raw_lock(raw_spinlock_t * l1,raw_spinlock_t * l2)2082 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
2083 {
2084 if (l1 > l2)
2085 swap(l1, l2);
2086
2087 raw_spin_lock(l1);
2088 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2089 }
2090
2091 /*
2092 * double_rq_lock - safely lock two runqueues
2093 *
2094 * Note this does not disable interrupts like task_rq_lock,
2095 * you need to do so manually before calling.
2096 */
double_rq_lock(struct rq * rq1,struct rq * rq2)2097 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2098 __acquires(rq1->lock)
2099 __acquires(rq2->lock)
2100 {
2101 BUG_ON(!irqs_disabled());
2102 if (rq1 == rq2) {
2103 raw_spin_lock(&rq1->lock);
2104 __acquire(rq2->lock); /* Fake it out ;) */
2105 } else {
2106 if (rq1 < rq2) {
2107 raw_spin_lock(&rq1->lock);
2108 raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
2109 } else {
2110 raw_spin_lock(&rq2->lock);
2111 raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
2112 }
2113 }
2114 }
2115
2116 /*
2117 * double_rq_unlock - safely unlock two runqueues
2118 *
2119 * Note this does not restore interrupts like task_rq_unlock,
2120 * you need to do so manually after calling.
2121 */
double_rq_unlock(struct rq * rq1,struct rq * rq2)2122 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2123 __releases(rq1->lock)
2124 __releases(rq2->lock)
2125 {
2126 raw_spin_unlock(&rq1->lock);
2127 if (rq1 != rq2)
2128 raw_spin_unlock(&rq2->lock);
2129 else
2130 __release(rq2->lock);
2131 }
2132
2133 extern void set_rq_online (struct rq *rq);
2134 extern void set_rq_offline(struct rq *rq);
2135 extern bool sched_smp_initialized;
2136
2137 #else /* CONFIG_SMP */
2138
2139 /*
2140 * double_rq_lock - safely lock two runqueues
2141 *
2142 * Note this does not disable interrupts like task_rq_lock,
2143 * you need to do so manually before calling.
2144 */
double_rq_lock(struct rq * rq1,struct rq * rq2)2145 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2146 __acquires(rq1->lock)
2147 __acquires(rq2->lock)
2148 {
2149 BUG_ON(!irqs_disabled());
2150 BUG_ON(rq1 != rq2);
2151 raw_spin_lock(&rq1->lock);
2152 __acquire(rq2->lock); /* Fake it out ;) */
2153 }
2154
2155 /*
2156 * double_rq_unlock - safely unlock two runqueues
2157 *
2158 * Note this does not restore interrupts like task_rq_unlock,
2159 * you need to do so manually after calling.
2160 */
double_rq_unlock(struct rq * rq1,struct rq * rq2)2161 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2162 __releases(rq1->lock)
2163 __releases(rq2->lock)
2164 {
2165 BUG_ON(rq1 != rq2);
2166 raw_spin_unlock(&rq1->lock);
2167 __release(rq2->lock);
2168 }
2169
2170 #endif
2171
2172 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
2173 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
2174
2175 #ifdef CONFIG_SCHED_DEBUG
2176 extern bool sched_debug_enabled;
2177
2178 extern void print_cfs_stats(struct seq_file *m, int cpu);
2179 extern void print_rt_stats(struct seq_file *m, int cpu);
2180 extern void print_dl_stats(struct seq_file *m, int cpu);
2181 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
2182 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
2183 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
2184 #ifdef CONFIG_NUMA_BALANCING
2185 extern void
2186 show_numa_stats(struct task_struct *p, struct seq_file *m);
2187 extern void
2188 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
2189 unsigned long tpf, unsigned long gsf, unsigned long gpf);
2190 #endif /* CONFIG_NUMA_BALANCING */
2191 #endif /* CONFIG_SCHED_DEBUG */
2192
2193 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
2194 extern void init_rt_rq(struct rt_rq *rt_rq);
2195 extern void init_dl_rq(struct dl_rq *dl_rq);
2196
2197 extern void cfs_bandwidth_usage_inc(void);
2198 extern void cfs_bandwidth_usage_dec(void);
2199
2200 #ifdef CONFIG_NO_HZ_COMMON
2201 #define NOHZ_BALANCE_KICK_BIT 0
2202 #define NOHZ_STATS_KICK_BIT 1
2203
2204 #define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT)
2205 #define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT)
2206
2207 #define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK)
2208
2209 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
2210
2211 extern void nohz_balance_exit_idle(struct rq *rq);
2212 #else
nohz_balance_exit_idle(struct rq * rq)2213 static inline void nohz_balance_exit_idle(struct rq *rq) { }
2214 #endif
2215
2216
2217 #ifdef CONFIG_SMP
2218 static inline
__dl_update(struct dl_bw * dl_b,s64 bw)2219 void __dl_update(struct dl_bw *dl_b, s64 bw)
2220 {
2221 struct root_domain *rd = container_of(dl_b, struct root_domain, dl_bw);
2222 int i;
2223
2224 RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
2225 "sched RCU must be held");
2226 for_each_cpu_and(i, rd->span, cpu_active_mask) {
2227 struct rq *rq = cpu_rq(i);
2228
2229 rq->dl.extra_bw += bw;
2230 }
2231 }
2232 #else
2233 static inline
__dl_update(struct dl_bw * dl_b,s64 bw)2234 void __dl_update(struct dl_bw *dl_b, s64 bw)
2235 {
2236 struct dl_rq *dl = container_of(dl_b, struct dl_rq, dl_bw);
2237
2238 dl->extra_bw += bw;
2239 }
2240 #endif
2241
2242
2243 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2244 struct irqtime {
2245 u64 total;
2246 u64 tick_delta;
2247 u64 irq_start_time;
2248 struct u64_stats_sync sync;
2249 };
2250
2251 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
2252
2253 /*
2254 * Returns the irqtime minus the softirq time computed by ksoftirqd.
2255 * Otherwise ksoftirqd's sum_exec_runtime is substracted its own runtime
2256 * and never move forward.
2257 */
irq_time_read(int cpu)2258 static inline u64 irq_time_read(int cpu)
2259 {
2260 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
2261 unsigned int seq;
2262 u64 total;
2263
2264 do {
2265 seq = __u64_stats_fetch_begin(&irqtime->sync);
2266 total = irqtime->total;
2267 } while (__u64_stats_fetch_retry(&irqtime->sync, seq));
2268
2269 return total;
2270 }
2271 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
2272
2273 #ifdef CONFIG_CPU_FREQ
2274 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
2275
2276 /**
2277 * cpufreq_update_util - Take a note about CPU utilization changes.
2278 * @rq: Runqueue to carry out the update for.
2279 * @flags: Update reason flags.
2280 *
2281 * This function is called by the scheduler on the CPU whose utilization is
2282 * being updated.
2283 *
2284 * It can only be called from RCU-sched read-side critical sections.
2285 *
2286 * The way cpufreq is currently arranged requires it to evaluate the CPU
2287 * performance state (frequency/voltage) on a regular basis to prevent it from
2288 * being stuck in a completely inadequate performance level for too long.
2289 * That is not guaranteed to happen if the updates are only triggered from CFS
2290 * and DL, though, because they may not be coming in if only RT tasks are
2291 * active all the time (or there are RT tasks only).
2292 *
2293 * As a workaround for that issue, this function is called periodically by the
2294 * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
2295 * but that really is a band-aid. Going forward it should be replaced with
2296 * solutions targeted more specifically at RT tasks.
2297 */
cpufreq_update_util(struct rq * rq,unsigned int flags)2298 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
2299 {
2300 struct update_util_data *data;
2301
2302 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
2303 cpu_of(rq)));
2304 if (data)
2305 data->func(data, rq_clock(rq), flags);
2306 }
2307 #else
cpufreq_update_util(struct rq * rq,unsigned int flags)2308 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
2309 #endif /* CONFIG_CPU_FREQ */
2310
2311 #ifdef CONFIG_UCLAMP_TASK
2312 enum uclamp_id uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
2313
2314 static __always_inline
uclamp_util_with(struct rq * rq,unsigned int util,struct task_struct * p)2315 unsigned int uclamp_util_with(struct rq *rq, unsigned int util,
2316 struct task_struct *p)
2317 {
2318 unsigned int min_util = READ_ONCE(rq->uclamp[UCLAMP_MIN].value);
2319 unsigned int max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
2320
2321 if (p) {
2322 min_util = max(min_util, uclamp_eff_value(p, UCLAMP_MIN));
2323 max_util = max(max_util, uclamp_eff_value(p, UCLAMP_MAX));
2324 }
2325
2326 /*
2327 * Since CPU's {min,max}_util clamps are MAX aggregated considering
2328 * RUNNABLE tasks with _different_ clamps, we can end up with an
2329 * inversion. Fix it now when the clamps are applied.
2330 */
2331 if (unlikely(min_util >= max_util))
2332 return min_util;
2333
2334 return clamp(util, min_util, max_util);
2335 }
2336
uclamp_util(struct rq * rq,unsigned int util)2337 static inline unsigned int uclamp_util(struct rq *rq, unsigned int util)
2338 {
2339 return uclamp_util_with(rq, util, NULL);
2340 }
2341 #else /* CONFIG_UCLAMP_TASK */
uclamp_util_with(struct rq * rq,unsigned int util,struct task_struct * p)2342 static inline unsigned int uclamp_util_with(struct rq *rq, unsigned int util,
2343 struct task_struct *p)
2344 {
2345 return util;
2346 }
uclamp_util(struct rq * rq,unsigned int util)2347 static inline unsigned int uclamp_util(struct rq *rq, unsigned int util)
2348 {
2349 return util;
2350 }
2351 #endif /* CONFIG_UCLAMP_TASK */
2352
2353 #ifdef arch_scale_freq_capacity
2354 # ifndef arch_scale_freq_invariant
2355 # define arch_scale_freq_invariant() true
2356 # endif
2357 #else
2358 # define arch_scale_freq_invariant() false
2359 #endif
2360
2361 #ifdef CONFIG_SMP
capacity_orig_of(int cpu)2362 static inline unsigned long capacity_orig_of(int cpu)
2363 {
2364 return cpu_rq(cpu)->cpu_capacity_orig;
2365 }
2366 #endif
2367
2368 /**
2369 * enum schedutil_type - CPU utilization type
2370 * @FREQUENCY_UTIL: Utilization used to select frequency
2371 * @ENERGY_UTIL: Utilization used during energy calculation
2372 *
2373 * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time
2374 * need to be aggregated differently depending on the usage made of them. This
2375 * enum is used within schedutil_freq_util() to differentiate the types of
2376 * utilization expected by the callers, and adjust the aggregation accordingly.
2377 */
2378 enum schedutil_type {
2379 FREQUENCY_UTIL,
2380 ENERGY_UTIL,
2381 };
2382
2383 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
2384
2385 unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
2386 unsigned long max, enum schedutil_type type,
2387 struct task_struct *p);
2388
cpu_bw_dl(struct rq * rq)2389 static inline unsigned long cpu_bw_dl(struct rq *rq)
2390 {
2391 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
2392 }
2393
cpu_util_dl(struct rq * rq)2394 static inline unsigned long cpu_util_dl(struct rq *rq)
2395 {
2396 return READ_ONCE(rq->avg_dl.util_avg);
2397 }
2398
cpu_util_cfs(struct rq * rq)2399 static inline unsigned long cpu_util_cfs(struct rq *rq)
2400 {
2401 unsigned long util = READ_ONCE(rq->cfs.avg.util_avg);
2402
2403 if (sched_feat(UTIL_EST)) {
2404 util = max_t(unsigned long, util,
2405 READ_ONCE(rq->cfs.avg.util_est.enqueued));
2406 }
2407
2408 return util;
2409 }
2410
cpu_util_rt(struct rq * rq)2411 static inline unsigned long cpu_util_rt(struct rq *rq)
2412 {
2413 return READ_ONCE(rq->avg_rt.util_avg);
2414 }
2415 #else /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
schedutil_cpu_util(int cpu,unsigned long util_cfs,unsigned long max,enum schedutil_type type,struct task_struct * p)2416 static inline unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
2417 unsigned long max, enum schedutil_type type,
2418 struct task_struct *p)
2419 {
2420 return 0;
2421 }
2422 #endif /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
2423
2424 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
cpu_util_irq(struct rq * rq)2425 static inline unsigned long cpu_util_irq(struct rq *rq)
2426 {
2427 return rq->avg_irq.util_avg;
2428 }
2429
2430 static inline
scale_irq_capacity(unsigned long util,unsigned long irq,unsigned long max)2431 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2432 {
2433 util *= (max - irq);
2434 util /= max;
2435
2436 return util;
2437
2438 }
2439 #else
cpu_util_irq(struct rq * rq)2440 static inline unsigned long cpu_util_irq(struct rq *rq)
2441 {
2442 return 0;
2443 }
2444
2445 static inline
scale_irq_capacity(unsigned long util,unsigned long irq,unsigned long max)2446 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2447 {
2448 return util;
2449 }
2450 #endif
2451
2452 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
2453
2454 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
2455
2456 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
2457
sched_energy_enabled(void)2458 static inline bool sched_energy_enabled(void)
2459 {
2460 return static_branch_unlikely(&sched_energy_present);
2461 }
2462
2463 #else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
2464
2465 #define perf_domain_span(pd) NULL
sched_energy_enabled(void)2466 static inline bool sched_energy_enabled(void) { return false; }
2467
2468 #endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
2469
2470 #ifdef CONFIG_MEMBARRIER
2471 /*
2472 * The scheduler provides memory barriers required by membarrier between:
2473 * - prior user-space memory accesses and store to rq->membarrier_state,
2474 * - store to rq->membarrier_state and following user-space memory accesses.
2475 * In the same way it provides those guarantees around store to rq->curr.
2476 */
membarrier_switch_mm(struct rq * rq,struct mm_struct * prev_mm,struct mm_struct * next_mm)2477 static inline void membarrier_switch_mm(struct rq *rq,
2478 struct mm_struct *prev_mm,
2479 struct mm_struct *next_mm)
2480 {
2481 int membarrier_state;
2482
2483 if (prev_mm == next_mm)
2484 return;
2485
2486 membarrier_state = atomic_read(&next_mm->membarrier_state);
2487 if (READ_ONCE(rq->membarrier_state) == membarrier_state)
2488 return;
2489
2490 WRITE_ONCE(rq->membarrier_state, membarrier_state);
2491 }
2492 #else
membarrier_switch_mm(struct rq * rq,struct mm_struct * prev_mm,struct mm_struct * next_mm)2493 static inline void membarrier_switch_mm(struct rq *rq,
2494 struct mm_struct *prev_mm,
2495 struct mm_struct *next_mm)
2496 {
2497 }
2498 #endif
2499