1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Scheduler internal types and methods:
4 */
5 #ifndef _KERNEL_SCHED_SCHED_H
6 #define _KERNEL_SCHED_SCHED_H
7
8 #include <linux/sched/affinity.h>
9 #include <linux/sched/autogroup.h>
10 #include <linux/sched/cpufreq.h>
11 #include <linux/sched/deadline.h>
12 #include <linux/sched.h>
13 #include <linux/sched/loadavg.h>
14 #include <linux/sched/mm.h>
15 #include <linux/sched/rseq_api.h>
16 #include <linux/sched/signal.h>
17 #include <linux/sched/smt.h>
18 #include <linux/sched/stat.h>
19 #include <linux/sched/sysctl.h>
20 #include <linux/sched/task_flags.h>
21 #include <linux/sched/task.h>
22 #include <linux/sched/topology.h>
23
24 #include <linux/atomic.h>
25 #include <linux/bitmap.h>
26 #include <linux/bug.h>
27 #include <linux/capability.h>
28 #include <linux/cgroup_api.h>
29 #include <linux/cgroup.h>
30 #include <linux/context_tracking.h>
31 #include <linux/cpufreq.h>
32 #include <linux/cpumask_api.h>
33 #include <linux/ctype.h>
34 #include <linux/file.h>
35 #include <linux/fs_api.h>
36 #include <linux/hrtimer_api.h>
37 #include <linux/interrupt.h>
38 #include <linux/irq_work.h>
39 #include <linux/jiffies.h>
40 #include <linux/kref_api.h>
41 #include <linux/kthread.h>
42 #include <linux/ktime_api.h>
43 #include <linux/lockdep_api.h>
44 #include <linux/lockdep.h>
45 #include <linux/minmax.h>
46 #include <linux/mm.h>
47 #include <linux/module.h>
48 #include <linux/mutex_api.h>
49 #include <linux/plist.h>
50 #include <linux/poll.h>
51 #include <linux/proc_fs.h>
52 #include <linux/profile.h>
53 #include <linux/psi.h>
54 #include <linux/rcupdate.h>
55 #include <linux/seq_file.h>
56 #include <linux/seqlock.h>
57 #include <linux/softirq.h>
58 #include <linux/spinlock_api.h>
59 #include <linux/static_key.h>
60 #include <linux/stop_machine.h>
61 #include <linux/syscalls_api.h>
62 #include <linux/syscalls.h>
63 #include <linux/tick.h>
64 #include <linux/topology.h>
65 #include <linux/types.h>
66 #include <linux/u64_stats_sync_api.h>
67 #include <linux/uaccess.h>
68 #include <linux/wait_api.h>
69 #include <linux/wait_bit.h>
70 #include <linux/workqueue_api.h>
71
72 #include <trace/events/power.h>
73 #include <trace/events/sched.h>
74
75 #include "../workqueue_internal.h"
76
77 #ifdef CONFIG_PARAVIRT
78 # include <asm/paravirt.h>
79 # include <asm/paravirt_api_clock.h>
80 #endif
81
82 #include "cpupri.h"
83 #include "cpudeadline.h"
84
85 #ifdef CONFIG_SCHED_DEBUG
86 # define SCHED_WARN_ON(x) WARN_ONCE(x, #x)
87 #else
88 # define SCHED_WARN_ON(x) ({ (void)(x), 0; })
89 #endif
90
91 struct rq;
92 struct cpuidle_state;
93
94 /* task_struct::on_rq states: */
95 #define TASK_ON_RQ_QUEUED 1
96 #define TASK_ON_RQ_MIGRATING 2
97
98 extern __read_mostly int scheduler_running;
99
100 extern unsigned long calc_load_update;
101 extern atomic_long_t calc_load_tasks;
102
103 extern void calc_global_load_tick(struct rq *this_rq);
104 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
105
106 extern void call_trace_sched_update_nr_running(struct rq *rq, int count);
107
108 extern int sysctl_sched_rt_period;
109 extern int sysctl_sched_rt_runtime;
110 extern int sched_rr_timeslice;
111
112 /*
113 * Helpers for converting nanosecond timing to jiffy resolution
114 */
115 #define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
116
117 /*
118 * Increase resolution of nice-level calculations for 64-bit architectures.
119 * The extra resolution improves shares distribution and load balancing of
120 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
121 * hierarchies, especially on larger systems. This is not a user-visible change
122 * and does not change the user-interface for setting shares/weights.
123 *
124 * We increase resolution only if we have enough bits to allow this increased
125 * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
126 * are pretty high and the returns do not justify the increased costs.
127 *
128 * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
129 * increase coverage and consistency always enable it on 64-bit platforms.
130 */
131 #ifdef CONFIG_64BIT
132 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
133 # define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT)
134 # define scale_load_down(w) \
135 ({ \
136 unsigned long __w = (w); \
137 if (__w) \
138 __w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \
139 __w; \
140 })
141 #else
142 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT)
143 # define scale_load(w) (w)
144 # define scale_load_down(w) (w)
145 #endif
146
147 /*
148 * Task weight (visible to users) and its load (invisible to users) have
149 * independent resolution, but they should be well calibrated. We use
150 * scale_load() and scale_load_down(w) to convert between them. The
151 * following must be true:
152 *
153 * scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD
154 *
155 */
156 #define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT)
157
158 /*
159 * Single value that decides SCHED_DEADLINE internal math precision.
160 * 10 -> just above 1us
161 * 9 -> just above 0.5us
162 */
163 #define DL_SCALE 10
164
165 /*
166 * Single value that denotes runtime == period, ie unlimited time.
167 */
168 #define RUNTIME_INF ((u64)~0ULL)
169
idle_policy(int policy)170 static inline int idle_policy(int policy)
171 {
172 return policy == SCHED_IDLE;
173 }
fair_policy(int policy)174 static inline int fair_policy(int policy)
175 {
176 return policy == SCHED_NORMAL || policy == SCHED_BATCH;
177 }
178
rt_policy(int policy)179 static inline int rt_policy(int policy)
180 {
181 return policy == SCHED_FIFO || policy == SCHED_RR;
182 }
183
dl_policy(int policy)184 static inline int dl_policy(int policy)
185 {
186 return policy == SCHED_DEADLINE;
187 }
valid_policy(int policy)188 static inline bool valid_policy(int policy)
189 {
190 return idle_policy(policy) || fair_policy(policy) ||
191 rt_policy(policy) || dl_policy(policy);
192 }
193
task_has_idle_policy(struct task_struct * p)194 static inline int task_has_idle_policy(struct task_struct *p)
195 {
196 return idle_policy(p->policy);
197 }
198
task_has_rt_policy(struct task_struct * p)199 static inline int task_has_rt_policy(struct task_struct *p)
200 {
201 return rt_policy(p->policy);
202 }
203
task_has_dl_policy(struct task_struct * p)204 static inline int task_has_dl_policy(struct task_struct *p)
205 {
206 return dl_policy(p->policy);
207 }
208
209 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
210
update_avg(u64 * avg,u64 sample)211 static inline void update_avg(u64 *avg, u64 sample)
212 {
213 s64 diff = sample - *avg;
214 *avg += diff / 8;
215 }
216
217 /*
218 * Shifting a value by an exponent greater *or equal* to the size of said value
219 * is UB; cap at size-1.
220 */
221 #define shr_bound(val, shift) \
222 (val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1))
223
224 /*
225 * !! For sched_setattr_nocheck() (kernel) only !!
226 *
227 * This is actually gross. :(
228 *
229 * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
230 * tasks, but still be able to sleep. We need this on platforms that cannot
231 * atomically change clock frequency. Remove once fast switching will be
232 * available on such platforms.
233 *
234 * SUGOV stands for SchedUtil GOVernor.
235 */
236 #define SCHED_FLAG_SUGOV 0x10000000
237
238 #define SCHED_DL_FLAGS (SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV)
239
dl_entity_is_special(const struct sched_dl_entity * dl_se)240 static inline bool dl_entity_is_special(const struct sched_dl_entity *dl_se)
241 {
242 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
243 return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
244 #else
245 return false;
246 #endif
247 }
248
249 /*
250 * Tells if entity @a should preempt entity @b.
251 */
dl_entity_preempt(const struct sched_dl_entity * a,const struct sched_dl_entity * b)252 static inline bool dl_entity_preempt(const struct sched_dl_entity *a,
253 const struct sched_dl_entity *b)
254 {
255 return dl_entity_is_special(a) ||
256 dl_time_before(a->deadline, b->deadline);
257 }
258
259 /*
260 * This is the priority-queue data structure of the RT scheduling class:
261 */
262 struct rt_prio_array {
263 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
264 struct list_head queue[MAX_RT_PRIO];
265 };
266
267 struct rt_bandwidth {
268 /* nests inside the rq lock: */
269 raw_spinlock_t rt_runtime_lock;
270 ktime_t rt_period;
271 u64 rt_runtime;
272 struct hrtimer rt_period_timer;
273 unsigned int rt_period_active;
274 };
275
dl_bandwidth_enabled(void)276 static inline int dl_bandwidth_enabled(void)
277 {
278 return sysctl_sched_rt_runtime >= 0;
279 }
280
281 /*
282 * To keep the bandwidth of -deadline tasks under control
283 * we need some place where:
284 * - store the maximum -deadline bandwidth of each cpu;
285 * - cache the fraction of bandwidth that is currently allocated in
286 * each root domain;
287 *
288 * This is all done in the data structure below. It is similar to the
289 * one used for RT-throttling (rt_bandwidth), with the main difference
290 * that, since here we are only interested in admission control, we
291 * do not decrease any runtime while the group "executes", neither we
292 * need a timer to replenish it.
293 *
294 * With respect to SMP, bandwidth is given on a per root domain basis,
295 * meaning that:
296 * - bw (< 100%) is the deadline bandwidth of each CPU;
297 * - total_bw is the currently allocated bandwidth in each root domain;
298 */
299 struct dl_bw {
300 raw_spinlock_t lock;
301 u64 bw;
302 u64 total_bw;
303 };
304
305 extern void init_dl_bw(struct dl_bw *dl_b);
306 extern int sched_dl_global_validate(void);
307 extern void sched_dl_do_global(void);
308 extern int sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
309 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
310 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
311 extern bool __checkparam_dl(const struct sched_attr *attr);
312 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
313 extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
314 extern int dl_bw_check_overflow(int cpu);
315
316 /*
317 * SCHED_DEADLINE supports servers (nested scheduling) with the following
318 * interface:
319 *
320 * dl_se::rq -- runqueue we belong to.
321 *
322 * dl_se::server_has_tasks() -- used on bandwidth enforcement; we 'stop' the
323 * server when it runs out of tasks to run.
324 *
325 * dl_se::server_pick() -- nested pick_next_task(); we yield the period if this
326 * returns NULL.
327 *
328 * dl_server_update() -- called from update_curr_common(), propagates runtime
329 * to the server.
330 *
331 * dl_server_start()
332 * dl_server_stop() -- start/stop the server when it has (no) tasks.
333 *
334 * dl_server_init() -- initializes the server.
335 */
336 extern void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec);
337 extern void dl_server_start(struct sched_dl_entity *dl_se);
338 extern void dl_server_stop(struct sched_dl_entity *dl_se);
339 extern void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq,
340 dl_server_has_tasks_f has_tasks,
341 dl_server_pick_f pick);
342
343 #ifdef CONFIG_CGROUP_SCHED
344
345 struct cfs_rq;
346 struct rt_rq;
347
348 extern struct list_head task_groups;
349
350 struct cfs_bandwidth {
351 #ifdef CONFIG_CFS_BANDWIDTH
352 raw_spinlock_t lock;
353 ktime_t period;
354 u64 quota;
355 u64 runtime;
356 u64 burst;
357 u64 runtime_snap;
358 s64 hierarchical_quota;
359
360 u8 idle;
361 u8 period_active;
362 u8 slack_started;
363 struct hrtimer period_timer;
364 struct hrtimer slack_timer;
365 struct list_head throttled_cfs_rq;
366
367 /* Statistics: */
368 int nr_periods;
369 int nr_throttled;
370 int nr_burst;
371 u64 throttled_time;
372 u64 burst_time;
373 #endif
374 };
375
376 /* Task group related information */
377 struct task_group {
378 struct cgroup_subsys_state css;
379
380 #ifdef CONFIG_FAIR_GROUP_SCHED
381 /* schedulable entities of this group on each CPU */
382 struct sched_entity **se;
383 /* runqueue "owned" by this group on each CPU */
384 struct cfs_rq **cfs_rq;
385 unsigned long shares;
386
387 /* A positive value indicates that this is a SCHED_IDLE group. */
388 int idle;
389
390 #ifdef CONFIG_SMP
391 /*
392 * load_avg can be heavily contended at clock tick time, so put
393 * it in its own cacheline separated from the fields above which
394 * will also be accessed at each tick.
395 */
396 atomic_long_t load_avg ____cacheline_aligned;
397 #endif
398 #endif
399
400 #ifdef CONFIG_RT_GROUP_SCHED
401 struct sched_rt_entity **rt_se;
402 struct rt_rq **rt_rq;
403
404 struct rt_bandwidth rt_bandwidth;
405 #endif
406
407 struct rcu_head rcu;
408 struct list_head list;
409
410 struct task_group *parent;
411 struct list_head siblings;
412 struct list_head children;
413
414 #ifdef CONFIG_SCHED_AUTOGROUP
415 struct autogroup *autogroup;
416 #endif
417
418 struct cfs_bandwidth cfs_bandwidth;
419
420 #ifdef CONFIG_UCLAMP_TASK_GROUP
421 /* The two decimal precision [%] value requested from user-space */
422 unsigned int uclamp_pct[UCLAMP_CNT];
423 /* Clamp values requested for a task group */
424 struct uclamp_se uclamp_req[UCLAMP_CNT];
425 /* Effective clamp values used for a task group */
426 struct uclamp_se uclamp[UCLAMP_CNT];
427 #endif
428
429 };
430
431 #ifdef CONFIG_FAIR_GROUP_SCHED
432 #define ROOT_TASK_GROUP_LOAD NICE_0_LOAD
433
434 /*
435 * A weight of 0 or 1 can cause arithmetics problems.
436 * A weight of a cfs_rq is the sum of weights of which entities
437 * are queued on this cfs_rq, so a weight of a entity should not be
438 * too large, so as the shares value of a task group.
439 * (The default weight is 1024 - so there's no practical
440 * limitation from this.)
441 */
442 #define MIN_SHARES (1UL << 1)
443 #define MAX_SHARES (1UL << 18)
444 #endif
445
446 typedef int (*tg_visitor)(struct task_group *, void *);
447
448 extern int walk_tg_tree_from(struct task_group *from,
449 tg_visitor down, tg_visitor up, void *data);
450
451 /*
452 * Iterate the full tree, calling @down when first entering a node and @up when
453 * leaving it for the final time.
454 *
455 * Caller must hold rcu_lock or sufficient equivalent.
456 */
walk_tg_tree(tg_visitor down,tg_visitor up,void * data)457 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
458 {
459 return walk_tg_tree_from(&root_task_group, down, up, data);
460 }
461
462 extern int tg_nop(struct task_group *tg, void *data);
463
464 #ifdef CONFIG_FAIR_GROUP_SCHED
465 extern void free_fair_sched_group(struct task_group *tg);
466 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
467 extern void online_fair_sched_group(struct task_group *tg);
468 extern void unregister_fair_sched_group(struct task_group *tg);
469 #else
free_fair_sched_group(struct task_group * tg)470 static inline void free_fair_sched_group(struct task_group *tg) { }
alloc_fair_sched_group(struct task_group * tg,struct task_group * parent)471 static inline int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
472 {
473 return 1;
474 }
online_fair_sched_group(struct task_group * tg)475 static inline void online_fair_sched_group(struct task_group *tg) { }
unregister_fair_sched_group(struct task_group * tg)476 static inline void unregister_fair_sched_group(struct task_group *tg) { }
477 #endif
478
479 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
480 struct sched_entity *se, int cpu,
481 struct sched_entity *parent);
482 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b, struct cfs_bandwidth *parent);
483
484 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
485 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
486 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
487 extern bool cfs_task_bw_constrained(struct task_struct *p);
488
489 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
490 struct sched_rt_entity *rt_se, int cpu,
491 struct sched_rt_entity *parent);
492 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
493 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
494 extern long sched_group_rt_runtime(struct task_group *tg);
495 extern long sched_group_rt_period(struct task_group *tg);
496 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
497
498 extern struct task_group *sched_create_group(struct task_group *parent);
499 extern void sched_online_group(struct task_group *tg,
500 struct task_group *parent);
501 extern void sched_destroy_group(struct task_group *tg);
502 extern void sched_release_group(struct task_group *tg);
503
504 extern void sched_move_task(struct task_struct *tsk);
505
506 #ifdef CONFIG_FAIR_GROUP_SCHED
507 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
508
509 extern int sched_group_set_idle(struct task_group *tg, long idle);
510
511 #ifdef CONFIG_SMP
512 extern void set_task_rq_fair(struct sched_entity *se,
513 struct cfs_rq *prev, struct cfs_rq *next);
514 #else /* !CONFIG_SMP */
set_task_rq_fair(struct sched_entity * se,struct cfs_rq * prev,struct cfs_rq * next)515 static inline void set_task_rq_fair(struct sched_entity *se,
516 struct cfs_rq *prev, struct cfs_rq *next) { }
517 #endif /* CONFIG_SMP */
518 #endif /* CONFIG_FAIR_GROUP_SCHED */
519
520 #else /* CONFIG_CGROUP_SCHED */
521
522 struct cfs_bandwidth { };
cfs_task_bw_constrained(struct task_struct * p)523 static inline bool cfs_task_bw_constrained(struct task_struct *p) { return false; }
524
525 #endif /* CONFIG_CGROUP_SCHED */
526
527 extern void unregister_rt_sched_group(struct task_group *tg);
528 extern void free_rt_sched_group(struct task_group *tg);
529 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
530
531 /*
532 * u64_u32_load/u64_u32_store
533 *
534 * Use a copy of a u64 value to protect against data race. This is only
535 * applicable for 32-bits architectures.
536 */
537 #ifdef CONFIG_64BIT
538 # define u64_u32_load_copy(var, copy) var
539 # define u64_u32_store_copy(var, copy, val) (var = val)
540 #else
541 # define u64_u32_load_copy(var, copy) \
542 ({ \
543 u64 __val, __val_copy; \
544 do { \
545 __val_copy = copy; \
546 /* \
547 * paired with u64_u32_store_copy(), ordering access \
548 * to var and copy. \
549 */ \
550 smp_rmb(); \
551 __val = var; \
552 } while (__val != __val_copy); \
553 __val; \
554 })
555 # define u64_u32_store_copy(var, copy, val) \
556 do { \
557 typeof(val) __val = (val); \
558 var = __val; \
559 /* \
560 * paired with u64_u32_load_copy(), ordering access to var and \
561 * copy. \
562 */ \
563 smp_wmb(); \
564 copy = __val; \
565 } while (0)
566 #endif
567 # define u64_u32_load(var) u64_u32_load_copy(var, var##_copy)
568 # define u64_u32_store(var, val) u64_u32_store_copy(var, var##_copy, val)
569
570 /* CFS-related fields in a runqueue */
571 struct cfs_rq {
572 struct load_weight load;
573 unsigned int nr_running;
574 unsigned int h_nr_running; /* SCHED_{NORMAL,BATCH,IDLE} */
575 unsigned int idle_nr_running; /* SCHED_IDLE */
576 unsigned int idle_h_nr_running; /* SCHED_IDLE */
577
578 s64 avg_vruntime;
579 u64 avg_load;
580
581 u64 exec_clock;
582 u64 min_vruntime;
583 #ifdef CONFIG_SCHED_CORE
584 unsigned int forceidle_seq;
585 u64 min_vruntime_fi;
586 #endif
587
588 #ifndef CONFIG_64BIT
589 u64 min_vruntime_copy;
590 #endif
591
592 struct rb_root_cached tasks_timeline;
593
594 /*
595 * 'curr' points to currently running entity on this cfs_rq.
596 * It is set to NULL otherwise (i.e when none are currently running).
597 */
598 struct sched_entity *curr;
599 struct sched_entity *next;
600
601 #ifdef CONFIG_SCHED_DEBUG
602 unsigned int nr_spread_over;
603 #endif
604
605 #ifdef CONFIG_SMP
606 /*
607 * CFS load tracking
608 */
609 struct sched_avg avg;
610 #ifndef CONFIG_64BIT
611 u64 last_update_time_copy;
612 #endif
613 struct {
614 raw_spinlock_t lock ____cacheline_aligned;
615 int nr;
616 unsigned long load_avg;
617 unsigned long util_avg;
618 unsigned long runnable_avg;
619 } removed;
620
621 #ifdef CONFIG_FAIR_GROUP_SCHED
622 u64 last_update_tg_load_avg;
623 unsigned long tg_load_avg_contrib;
624 long propagate;
625 long prop_runnable_sum;
626
627 /*
628 * h_load = weight * f(tg)
629 *
630 * Where f(tg) is the recursive weight fraction assigned to
631 * this group.
632 */
633 unsigned long h_load;
634 u64 last_h_load_update;
635 struct sched_entity *h_load_next;
636 #endif /* CONFIG_FAIR_GROUP_SCHED */
637 #endif /* CONFIG_SMP */
638
639 #ifdef CONFIG_FAIR_GROUP_SCHED
640 struct rq *rq; /* CPU runqueue to which this cfs_rq is attached */
641
642 /*
643 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
644 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
645 * (like users, containers etc.)
646 *
647 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
648 * This list is used during load balance.
649 */
650 int on_list;
651 struct list_head leaf_cfs_rq_list;
652 struct task_group *tg; /* group that "owns" this runqueue */
653
654 /* Locally cached copy of our task_group's idle value */
655 int idle;
656
657 #ifdef CONFIG_CFS_BANDWIDTH
658 int runtime_enabled;
659 s64 runtime_remaining;
660
661 u64 throttled_pelt_idle;
662 #ifndef CONFIG_64BIT
663 u64 throttled_pelt_idle_copy;
664 #endif
665 u64 throttled_clock;
666 u64 throttled_clock_pelt;
667 u64 throttled_clock_pelt_time;
668 u64 throttled_clock_self;
669 u64 throttled_clock_self_time;
670 int throttled;
671 int throttle_count;
672 struct list_head throttled_list;
673 struct list_head throttled_csd_list;
674 #endif /* CONFIG_CFS_BANDWIDTH */
675 #endif /* CONFIG_FAIR_GROUP_SCHED */
676 };
677
rt_bandwidth_enabled(void)678 static inline int rt_bandwidth_enabled(void)
679 {
680 return sysctl_sched_rt_runtime >= 0;
681 }
682
683 /* RT IPI pull logic requires IRQ_WORK */
684 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
685 # define HAVE_RT_PUSH_IPI
686 #endif
687
688 /* Real-Time classes' related field in a runqueue: */
689 struct rt_rq {
690 struct rt_prio_array active;
691 unsigned int rt_nr_running;
692 unsigned int rr_nr_running;
693 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
694 struct {
695 int curr; /* highest queued rt task prio */
696 #ifdef CONFIG_SMP
697 int next; /* next highest */
698 #endif
699 } highest_prio;
700 #endif
701 #ifdef CONFIG_SMP
702 int overloaded;
703 struct plist_head pushable_tasks;
704
705 #endif /* CONFIG_SMP */
706 int rt_queued;
707
708 int rt_throttled;
709 u64 rt_time;
710 u64 rt_runtime;
711 /* Nests inside the rq lock: */
712 raw_spinlock_t rt_runtime_lock;
713
714 #ifdef CONFIG_RT_GROUP_SCHED
715 unsigned int rt_nr_boosted;
716
717 struct rq *rq;
718 struct task_group *tg;
719 #endif
720 };
721
rt_rq_is_runnable(struct rt_rq * rt_rq)722 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
723 {
724 return rt_rq->rt_queued && rt_rq->rt_nr_running;
725 }
726
727 /* Deadline class' related fields in a runqueue */
728 struct dl_rq {
729 /* runqueue is an rbtree, ordered by deadline */
730 struct rb_root_cached root;
731
732 unsigned int dl_nr_running;
733
734 #ifdef CONFIG_SMP
735 /*
736 * Deadline values of the currently executing and the
737 * earliest ready task on this rq. Caching these facilitates
738 * the decision whether or not a ready but not running task
739 * should migrate somewhere else.
740 */
741 struct {
742 u64 curr;
743 u64 next;
744 } earliest_dl;
745
746 int overloaded;
747
748 /*
749 * Tasks on this rq that can be pushed away. They are kept in
750 * an rb-tree, ordered by tasks' deadlines, with caching
751 * of the leftmost (earliest deadline) element.
752 */
753 struct rb_root_cached pushable_dl_tasks_root;
754 #else
755 struct dl_bw dl_bw;
756 #endif
757 /*
758 * "Active utilization" for this runqueue: increased when a
759 * task wakes up (becomes TASK_RUNNING) and decreased when a
760 * task blocks
761 */
762 u64 running_bw;
763
764 /*
765 * Utilization of the tasks "assigned" to this runqueue (including
766 * the tasks that are in runqueue and the tasks that executed on this
767 * CPU and blocked). Increased when a task moves to this runqueue, and
768 * decreased when the task moves away (migrates, changes scheduling
769 * policy, or terminates).
770 * This is needed to compute the "inactive utilization" for the
771 * runqueue (inactive utilization = this_bw - running_bw).
772 */
773 u64 this_bw;
774 u64 extra_bw;
775
776 /*
777 * Maximum available bandwidth for reclaiming by SCHED_FLAG_RECLAIM
778 * tasks of this rq. Used in calculation of reclaimable bandwidth(GRUB).
779 */
780 u64 max_bw;
781
782 /*
783 * Inverse of the fraction of CPU utilization that can be reclaimed
784 * by the GRUB algorithm.
785 */
786 u64 bw_ratio;
787 };
788
789 #ifdef CONFIG_FAIR_GROUP_SCHED
790 /* An entity is a task if it doesn't "own" a runqueue */
791 #define entity_is_task(se) (!se->my_q)
792
se_update_runnable(struct sched_entity * se)793 static inline void se_update_runnable(struct sched_entity *se)
794 {
795 if (!entity_is_task(se))
796 se->runnable_weight = se->my_q->h_nr_running;
797 }
798
se_runnable(struct sched_entity * se)799 static inline long se_runnable(struct sched_entity *se)
800 {
801 if (entity_is_task(se))
802 return !!se->on_rq;
803 else
804 return se->runnable_weight;
805 }
806
807 #else
808 #define entity_is_task(se) 1
809
se_update_runnable(struct sched_entity * se)810 static inline void se_update_runnable(struct sched_entity *se) {}
811
se_runnable(struct sched_entity * se)812 static inline long se_runnable(struct sched_entity *se)
813 {
814 return !!se->on_rq;
815 }
816 #endif
817
818 #ifdef CONFIG_SMP
819 /*
820 * XXX we want to get rid of these helpers and use the full load resolution.
821 */
se_weight(struct sched_entity * se)822 static inline long se_weight(struct sched_entity *se)
823 {
824 return scale_load_down(se->load.weight);
825 }
826
827
sched_asym_prefer(int a,int b)828 static inline bool sched_asym_prefer(int a, int b)
829 {
830 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
831 }
832
833 struct perf_domain {
834 struct em_perf_domain *em_pd;
835 struct perf_domain *next;
836 struct rcu_head rcu;
837 };
838
839 /* Scheduling group status flags */
840 #define SG_OVERLOAD 0x1 /* More than one runnable task on a CPU. */
841 #define SG_OVERUTILIZED 0x2 /* One or more CPUs are over-utilized. */
842
843 /*
844 * We add the notion of a root-domain which will be used to define per-domain
845 * variables. Each exclusive cpuset essentially defines an island domain by
846 * fully partitioning the member CPUs from any other cpuset. Whenever a new
847 * exclusive cpuset is created, we also create and attach a new root-domain
848 * object.
849 *
850 */
851 struct root_domain {
852 atomic_t refcount;
853 atomic_t rto_count;
854 struct rcu_head rcu;
855 cpumask_var_t span;
856 cpumask_var_t online;
857
858 /*
859 * Indicate pullable load on at least one CPU, e.g:
860 * - More than one runnable task
861 * - Running task is misfit
862 */
863 int overload;
864
865 /* Indicate one or more cpus over-utilized (tipping point) */
866 int overutilized;
867
868 /*
869 * The bit corresponding to a CPU gets set here if such CPU has more
870 * than one runnable -deadline task (as it is below for RT tasks).
871 */
872 cpumask_var_t dlo_mask;
873 atomic_t dlo_count;
874 struct dl_bw dl_bw;
875 struct cpudl cpudl;
876
877 /*
878 * Indicate whether a root_domain's dl_bw has been checked or
879 * updated. It's monotonously increasing value.
880 *
881 * Also, some corner cases, like 'wrap around' is dangerous, but given
882 * that u64 is 'big enough'. So that shouldn't be a concern.
883 */
884 u64 visit_gen;
885
886 #ifdef HAVE_RT_PUSH_IPI
887 /*
888 * For IPI pull requests, loop across the rto_mask.
889 */
890 struct irq_work rto_push_work;
891 raw_spinlock_t rto_lock;
892 /* These are only updated and read within rto_lock */
893 int rto_loop;
894 int rto_cpu;
895 /* These atomics are updated outside of a lock */
896 atomic_t rto_loop_next;
897 atomic_t rto_loop_start;
898 #endif
899 /*
900 * The "RT overload" flag: it gets set if a CPU has more than
901 * one runnable RT task.
902 */
903 cpumask_var_t rto_mask;
904 struct cpupri cpupri;
905
906 unsigned long max_cpu_capacity;
907
908 /*
909 * NULL-terminated list of performance domains intersecting with the
910 * CPUs of the rd. Protected by RCU.
911 */
912 struct perf_domain __rcu *pd;
913 };
914
915 extern void init_defrootdomain(void);
916 extern int sched_init_domains(const struct cpumask *cpu_map);
917 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
918 extern void sched_get_rd(struct root_domain *rd);
919 extern void sched_put_rd(struct root_domain *rd);
920
921 #ifdef HAVE_RT_PUSH_IPI
922 extern void rto_push_irq_work_func(struct irq_work *work);
923 #endif
924 #endif /* CONFIG_SMP */
925
926 #ifdef CONFIG_UCLAMP_TASK
927 /*
928 * struct uclamp_bucket - Utilization clamp bucket
929 * @value: utilization clamp value for tasks on this clamp bucket
930 * @tasks: number of RUNNABLE tasks on this clamp bucket
931 *
932 * Keep track of how many tasks are RUNNABLE for a given utilization
933 * clamp value.
934 */
935 struct uclamp_bucket {
936 unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
937 unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
938 };
939
940 /*
941 * struct uclamp_rq - rq's utilization clamp
942 * @value: currently active clamp values for a rq
943 * @bucket: utilization clamp buckets affecting a rq
944 *
945 * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
946 * A clamp value is affecting a rq when there is at least one task RUNNABLE
947 * (or actually running) with that value.
948 *
949 * There are up to UCLAMP_CNT possible different clamp values, currently there
950 * are only two: minimum utilization and maximum utilization.
951 *
952 * All utilization clamping values are MAX aggregated, since:
953 * - for util_min: we want to run the CPU at least at the max of the minimum
954 * utilization required by its currently RUNNABLE tasks.
955 * - for util_max: we want to allow the CPU to run up to the max of the
956 * maximum utilization allowed by its currently RUNNABLE tasks.
957 *
958 * Since on each system we expect only a limited number of different
959 * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
960 * the metrics required to compute all the per-rq utilization clamp values.
961 */
962 struct uclamp_rq {
963 unsigned int value;
964 struct uclamp_bucket bucket[UCLAMP_BUCKETS];
965 };
966
967 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
968 #endif /* CONFIG_UCLAMP_TASK */
969
970 struct rq;
971 struct balance_callback {
972 struct balance_callback *next;
973 void (*func)(struct rq *rq);
974 };
975
976 /*
977 * This is the main, per-CPU runqueue data structure.
978 *
979 * Locking rule: those places that want to lock multiple runqueues
980 * (such as the load balancing or the thread migration code), lock
981 * acquire operations must be ordered by ascending &runqueue.
982 */
983 struct rq {
984 /* runqueue lock: */
985 raw_spinlock_t __lock;
986
987 unsigned int nr_running;
988 #ifdef CONFIG_NUMA_BALANCING
989 unsigned int nr_numa_running;
990 unsigned int nr_preferred_running;
991 unsigned int numa_migrate_on;
992 #endif
993 #ifdef CONFIG_NO_HZ_COMMON
994 #ifdef CONFIG_SMP
995 unsigned long last_blocked_load_update_tick;
996 unsigned int has_blocked_load;
997 call_single_data_t nohz_csd;
998 #endif /* CONFIG_SMP */
999 unsigned int nohz_tick_stopped;
1000 atomic_t nohz_flags;
1001 #endif /* CONFIG_NO_HZ_COMMON */
1002
1003 #ifdef CONFIG_SMP
1004 unsigned int ttwu_pending;
1005 #endif
1006 u64 nr_switches;
1007
1008 #ifdef CONFIG_UCLAMP_TASK
1009 /* Utilization clamp values based on CPU's RUNNABLE tasks */
1010 struct uclamp_rq uclamp[UCLAMP_CNT] ____cacheline_aligned;
1011 unsigned int uclamp_flags;
1012 #define UCLAMP_FLAG_IDLE 0x01
1013 #endif
1014
1015 struct cfs_rq cfs;
1016 struct rt_rq rt;
1017 struct dl_rq dl;
1018
1019 #ifdef CONFIG_FAIR_GROUP_SCHED
1020 /* list of leaf cfs_rq on this CPU: */
1021 struct list_head leaf_cfs_rq_list;
1022 struct list_head *tmp_alone_branch;
1023 #endif /* CONFIG_FAIR_GROUP_SCHED */
1024
1025 /*
1026 * This is part of a global counter where only the total sum
1027 * over all CPUs matters. A task can increase this counter on
1028 * one CPU and if it got migrated afterwards it may decrease
1029 * it on another CPU. Always updated under the runqueue lock:
1030 */
1031 unsigned int nr_uninterruptible;
1032
1033 struct task_struct __rcu *curr;
1034 struct task_struct *idle;
1035 struct task_struct *stop;
1036 unsigned long next_balance;
1037 struct mm_struct *prev_mm;
1038
1039 unsigned int clock_update_flags;
1040 u64 clock;
1041 /* Ensure that all clocks are in the same cache line */
1042 u64 clock_task ____cacheline_aligned;
1043 u64 clock_pelt;
1044 unsigned long lost_idle_time;
1045 u64 clock_pelt_idle;
1046 u64 clock_idle;
1047 #ifndef CONFIG_64BIT
1048 u64 clock_pelt_idle_copy;
1049 u64 clock_idle_copy;
1050 #endif
1051
1052 atomic_t nr_iowait;
1053
1054 #ifdef CONFIG_SCHED_DEBUG
1055 u64 last_seen_need_resched_ns;
1056 int ticks_without_resched;
1057 #endif
1058
1059 #ifdef CONFIG_MEMBARRIER
1060 int membarrier_state;
1061 #endif
1062
1063 #ifdef CONFIG_SMP
1064 struct root_domain *rd;
1065 struct sched_domain __rcu *sd;
1066
1067 unsigned long cpu_capacity;
1068
1069 struct balance_callback *balance_callback;
1070
1071 unsigned char nohz_idle_balance;
1072 unsigned char idle_balance;
1073
1074 unsigned long misfit_task_load;
1075
1076 /* For active balancing */
1077 int active_balance;
1078 int push_cpu;
1079 struct cpu_stop_work active_balance_work;
1080
1081 /* CPU of this runqueue: */
1082 int cpu;
1083 int online;
1084
1085 struct list_head cfs_tasks;
1086
1087 struct sched_avg avg_rt;
1088 struct sched_avg avg_dl;
1089 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1090 struct sched_avg avg_irq;
1091 #endif
1092 #ifdef CONFIG_SCHED_THERMAL_PRESSURE
1093 struct sched_avg avg_thermal;
1094 #endif
1095 u64 idle_stamp;
1096 u64 avg_idle;
1097
1098 /* This is used to determine avg_idle's max value */
1099 u64 max_idle_balance_cost;
1100
1101 #ifdef CONFIG_HOTPLUG_CPU
1102 struct rcuwait hotplug_wait;
1103 #endif
1104 #endif /* CONFIG_SMP */
1105
1106 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1107 u64 prev_irq_time;
1108 #endif
1109 #ifdef CONFIG_PARAVIRT
1110 u64 prev_steal_time;
1111 #endif
1112 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1113 u64 prev_steal_time_rq;
1114 #endif
1115
1116 /* calc_load related fields */
1117 unsigned long calc_load_update;
1118 long calc_load_active;
1119
1120 #ifdef CONFIG_SCHED_HRTICK
1121 #ifdef CONFIG_SMP
1122 call_single_data_t hrtick_csd;
1123 #endif
1124 struct hrtimer hrtick_timer;
1125 ktime_t hrtick_time;
1126 #endif
1127
1128 #ifdef CONFIG_SCHEDSTATS
1129 /* latency stats */
1130 struct sched_info rq_sched_info;
1131 unsigned long long rq_cpu_time;
1132 /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
1133
1134 /* sys_sched_yield() stats */
1135 unsigned int yld_count;
1136
1137 /* schedule() stats */
1138 unsigned int sched_count;
1139 unsigned int sched_goidle;
1140
1141 /* try_to_wake_up() stats */
1142 unsigned int ttwu_count;
1143 unsigned int ttwu_local;
1144 #endif
1145
1146 #ifdef CONFIG_CPU_IDLE
1147 /* Must be inspected within a rcu lock section */
1148 struct cpuidle_state *idle_state;
1149 #endif
1150
1151 #ifdef CONFIG_SMP
1152 unsigned int nr_pinned;
1153 #endif
1154 unsigned int push_busy;
1155 struct cpu_stop_work push_work;
1156
1157 #ifdef CONFIG_SCHED_CORE
1158 /* per rq */
1159 struct rq *core;
1160 struct task_struct *core_pick;
1161 unsigned int core_enabled;
1162 unsigned int core_sched_seq;
1163 struct rb_root core_tree;
1164
1165 /* shared state -- careful with sched_core_cpu_deactivate() */
1166 unsigned int core_task_seq;
1167 unsigned int core_pick_seq;
1168 unsigned long core_cookie;
1169 unsigned int core_forceidle_count;
1170 unsigned int core_forceidle_seq;
1171 unsigned int core_forceidle_occupation;
1172 u64 core_forceidle_start;
1173 #endif
1174
1175 /* Scratch cpumask to be temporarily used under rq_lock */
1176 cpumask_var_t scratch_mask;
1177
1178 #if defined(CONFIG_CFS_BANDWIDTH) && defined(CONFIG_SMP)
1179 call_single_data_t cfsb_csd;
1180 struct list_head cfsb_csd_list;
1181 #endif
1182 };
1183
1184 #ifdef CONFIG_FAIR_GROUP_SCHED
1185
1186 /* CPU runqueue to which this cfs_rq is attached */
rq_of(struct cfs_rq * cfs_rq)1187 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1188 {
1189 return cfs_rq->rq;
1190 }
1191
1192 #else
1193
rq_of(struct cfs_rq * cfs_rq)1194 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1195 {
1196 return container_of(cfs_rq, struct rq, cfs);
1197 }
1198 #endif
1199
cpu_of(struct rq * rq)1200 static inline int cpu_of(struct rq *rq)
1201 {
1202 #ifdef CONFIG_SMP
1203 return rq->cpu;
1204 #else
1205 return 0;
1206 #endif
1207 }
1208
1209 #define MDF_PUSH 0x01
1210
is_migration_disabled(struct task_struct * p)1211 static inline bool is_migration_disabled(struct task_struct *p)
1212 {
1213 #ifdef CONFIG_SMP
1214 return p->migration_disabled;
1215 #else
1216 return false;
1217 #endif
1218 }
1219
1220 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1221
1222 #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
1223 #define this_rq() this_cpu_ptr(&runqueues)
1224 #define task_rq(p) cpu_rq(task_cpu(p))
1225 #define cpu_curr(cpu) (cpu_rq(cpu)->curr)
1226 #define raw_rq() raw_cpu_ptr(&runqueues)
1227
1228 struct sched_group;
1229 #ifdef CONFIG_SCHED_CORE
1230 static inline struct cpumask *sched_group_span(struct sched_group *sg);
1231
1232 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled);
1233
sched_core_enabled(struct rq * rq)1234 static inline bool sched_core_enabled(struct rq *rq)
1235 {
1236 return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled;
1237 }
1238
sched_core_disabled(void)1239 static inline bool sched_core_disabled(void)
1240 {
1241 return !static_branch_unlikely(&__sched_core_enabled);
1242 }
1243
1244 /*
1245 * Be careful with this function; not for general use. The return value isn't
1246 * stable unless you actually hold a relevant rq->__lock.
1247 */
rq_lockp(struct rq * rq)1248 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1249 {
1250 if (sched_core_enabled(rq))
1251 return &rq->core->__lock;
1252
1253 return &rq->__lock;
1254 }
1255
__rq_lockp(struct rq * rq)1256 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1257 {
1258 if (rq->core_enabled)
1259 return &rq->core->__lock;
1260
1261 return &rq->__lock;
1262 }
1263
1264 bool cfs_prio_less(const struct task_struct *a, const struct task_struct *b,
1265 bool fi);
1266 void task_vruntime_update(struct rq *rq, struct task_struct *p, bool in_fi);
1267
1268 /*
1269 * Helpers to check if the CPU's core cookie matches with the task's cookie
1270 * when core scheduling is enabled.
1271 * A special case is that the task's cookie always matches with CPU's core
1272 * cookie if the CPU is in an idle core.
1273 */
sched_cpu_cookie_match(struct rq * rq,struct task_struct * p)1274 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1275 {
1276 /* Ignore cookie match if core scheduler is not enabled on the CPU. */
1277 if (!sched_core_enabled(rq))
1278 return true;
1279
1280 return rq->core->core_cookie == p->core_cookie;
1281 }
1282
sched_core_cookie_match(struct rq * rq,struct task_struct * p)1283 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1284 {
1285 bool idle_core = true;
1286 int cpu;
1287
1288 /* Ignore cookie match if core scheduler is not enabled on the CPU. */
1289 if (!sched_core_enabled(rq))
1290 return true;
1291
1292 for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) {
1293 if (!available_idle_cpu(cpu)) {
1294 idle_core = false;
1295 break;
1296 }
1297 }
1298
1299 /*
1300 * A CPU in an idle core is always the best choice for tasks with
1301 * cookies.
1302 */
1303 return idle_core || rq->core->core_cookie == p->core_cookie;
1304 }
1305
sched_group_cookie_match(struct rq * rq,struct task_struct * p,struct sched_group * group)1306 static inline bool sched_group_cookie_match(struct rq *rq,
1307 struct task_struct *p,
1308 struct sched_group *group)
1309 {
1310 int cpu;
1311
1312 /* Ignore cookie match if core scheduler is not enabled on the CPU. */
1313 if (!sched_core_enabled(rq))
1314 return true;
1315
1316 for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
1317 if (sched_core_cookie_match(cpu_rq(cpu), p))
1318 return true;
1319 }
1320 return false;
1321 }
1322
sched_core_enqueued(struct task_struct * p)1323 static inline bool sched_core_enqueued(struct task_struct *p)
1324 {
1325 return !RB_EMPTY_NODE(&p->core_node);
1326 }
1327
1328 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p);
1329 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags);
1330
1331 extern void sched_core_get(void);
1332 extern void sched_core_put(void);
1333
1334 #else /* !CONFIG_SCHED_CORE */
1335
sched_core_enabled(struct rq * rq)1336 static inline bool sched_core_enabled(struct rq *rq)
1337 {
1338 return false;
1339 }
1340
sched_core_disabled(void)1341 static inline bool sched_core_disabled(void)
1342 {
1343 return true;
1344 }
1345
rq_lockp(struct rq * rq)1346 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1347 {
1348 return &rq->__lock;
1349 }
1350
__rq_lockp(struct rq * rq)1351 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1352 {
1353 return &rq->__lock;
1354 }
1355
sched_cpu_cookie_match(struct rq * rq,struct task_struct * p)1356 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1357 {
1358 return true;
1359 }
1360
sched_core_cookie_match(struct rq * rq,struct task_struct * p)1361 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1362 {
1363 return true;
1364 }
1365
sched_group_cookie_match(struct rq * rq,struct task_struct * p,struct sched_group * group)1366 static inline bool sched_group_cookie_match(struct rq *rq,
1367 struct task_struct *p,
1368 struct sched_group *group)
1369 {
1370 return true;
1371 }
1372 #endif /* CONFIG_SCHED_CORE */
1373
lockdep_assert_rq_held(struct rq * rq)1374 static inline void lockdep_assert_rq_held(struct rq *rq)
1375 {
1376 lockdep_assert_held(__rq_lockp(rq));
1377 }
1378
1379 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass);
1380 extern bool raw_spin_rq_trylock(struct rq *rq);
1381 extern void raw_spin_rq_unlock(struct rq *rq);
1382
raw_spin_rq_lock(struct rq * rq)1383 static inline void raw_spin_rq_lock(struct rq *rq)
1384 {
1385 raw_spin_rq_lock_nested(rq, 0);
1386 }
1387
raw_spin_rq_lock_irq(struct rq * rq)1388 static inline void raw_spin_rq_lock_irq(struct rq *rq)
1389 {
1390 local_irq_disable();
1391 raw_spin_rq_lock(rq);
1392 }
1393
raw_spin_rq_unlock_irq(struct rq * rq)1394 static inline void raw_spin_rq_unlock_irq(struct rq *rq)
1395 {
1396 raw_spin_rq_unlock(rq);
1397 local_irq_enable();
1398 }
1399
_raw_spin_rq_lock_irqsave(struct rq * rq)1400 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq)
1401 {
1402 unsigned long flags;
1403 local_irq_save(flags);
1404 raw_spin_rq_lock(rq);
1405 return flags;
1406 }
1407
raw_spin_rq_unlock_irqrestore(struct rq * rq,unsigned long flags)1408 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags)
1409 {
1410 raw_spin_rq_unlock(rq);
1411 local_irq_restore(flags);
1412 }
1413
1414 #define raw_spin_rq_lock_irqsave(rq, flags) \
1415 do { \
1416 flags = _raw_spin_rq_lock_irqsave(rq); \
1417 } while (0)
1418
1419 #ifdef CONFIG_SCHED_SMT
1420 extern void __update_idle_core(struct rq *rq);
1421
update_idle_core(struct rq * rq)1422 static inline void update_idle_core(struct rq *rq)
1423 {
1424 if (static_branch_unlikely(&sched_smt_present))
1425 __update_idle_core(rq);
1426 }
1427
1428 #else
update_idle_core(struct rq * rq)1429 static inline void update_idle_core(struct rq *rq) { }
1430 #endif
1431
1432 #ifdef CONFIG_FAIR_GROUP_SCHED
task_of(struct sched_entity * se)1433 static inline struct task_struct *task_of(struct sched_entity *se)
1434 {
1435 SCHED_WARN_ON(!entity_is_task(se));
1436 return container_of(se, struct task_struct, se);
1437 }
1438
task_cfs_rq(struct task_struct * p)1439 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1440 {
1441 return p->se.cfs_rq;
1442 }
1443
1444 /* runqueue on which this entity is (to be) queued */
cfs_rq_of(const struct sched_entity * se)1445 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1446 {
1447 return se->cfs_rq;
1448 }
1449
1450 /* runqueue "owned" by this group */
group_cfs_rq(struct sched_entity * grp)1451 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1452 {
1453 return grp->my_q;
1454 }
1455
1456 #else
1457
1458 #define task_of(_se) container_of(_se, struct task_struct, se)
1459
task_cfs_rq(const struct task_struct * p)1460 static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p)
1461 {
1462 return &task_rq(p)->cfs;
1463 }
1464
cfs_rq_of(const struct sched_entity * se)1465 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1466 {
1467 const struct task_struct *p = task_of(se);
1468 struct rq *rq = task_rq(p);
1469
1470 return &rq->cfs;
1471 }
1472
1473 /* runqueue "owned" by this group */
group_cfs_rq(struct sched_entity * grp)1474 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1475 {
1476 return NULL;
1477 }
1478 #endif
1479
1480 extern void update_rq_clock(struct rq *rq);
1481
1482 /*
1483 * rq::clock_update_flags bits
1484 *
1485 * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1486 * call to __schedule(). This is an optimisation to avoid
1487 * neighbouring rq clock updates.
1488 *
1489 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1490 * in effect and calls to update_rq_clock() are being ignored.
1491 *
1492 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1493 * made to update_rq_clock() since the last time rq::lock was pinned.
1494 *
1495 * If inside of __schedule(), clock_update_flags will have been
1496 * shifted left (a left shift is a cheap operation for the fast path
1497 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1498 *
1499 * if (rq-clock_update_flags >= RQCF_UPDATED)
1500 *
1501 * to check if %RQCF_UPDATED is set. It'll never be shifted more than
1502 * one position though, because the next rq_unpin_lock() will shift it
1503 * back.
1504 */
1505 #define RQCF_REQ_SKIP 0x01
1506 #define RQCF_ACT_SKIP 0x02
1507 #define RQCF_UPDATED 0x04
1508
assert_clock_updated(struct rq * rq)1509 static inline void assert_clock_updated(struct rq *rq)
1510 {
1511 /*
1512 * The only reason for not seeing a clock update since the
1513 * last rq_pin_lock() is if we're currently skipping updates.
1514 */
1515 SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
1516 }
1517
rq_clock(struct rq * rq)1518 static inline u64 rq_clock(struct rq *rq)
1519 {
1520 lockdep_assert_rq_held(rq);
1521 assert_clock_updated(rq);
1522
1523 return rq->clock;
1524 }
1525
rq_clock_task(struct rq * rq)1526 static inline u64 rq_clock_task(struct rq *rq)
1527 {
1528 lockdep_assert_rq_held(rq);
1529 assert_clock_updated(rq);
1530
1531 return rq->clock_task;
1532 }
1533
1534 /**
1535 * By default the decay is the default pelt decay period.
1536 * The decay shift can change the decay period in
1537 * multiples of 32.
1538 * Decay shift Decay period(ms)
1539 * 0 32
1540 * 1 64
1541 * 2 128
1542 * 3 256
1543 * 4 512
1544 */
1545 extern int sched_thermal_decay_shift;
1546
rq_clock_thermal(struct rq * rq)1547 static inline u64 rq_clock_thermal(struct rq *rq)
1548 {
1549 return rq_clock_task(rq) >> sched_thermal_decay_shift;
1550 }
1551
rq_clock_skip_update(struct rq * rq)1552 static inline void rq_clock_skip_update(struct rq *rq)
1553 {
1554 lockdep_assert_rq_held(rq);
1555 rq->clock_update_flags |= RQCF_REQ_SKIP;
1556 }
1557
1558 /*
1559 * See rt task throttling, which is the only time a skip
1560 * request is canceled.
1561 */
rq_clock_cancel_skipupdate(struct rq * rq)1562 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1563 {
1564 lockdep_assert_rq_held(rq);
1565 rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1566 }
1567
1568 /*
1569 * During cpu offlining and rq wide unthrottling, we can trigger
1570 * an update_rq_clock() for several cfs and rt runqueues (Typically
1571 * when using list_for_each_entry_*)
1572 * rq_clock_start_loop_update() can be called after updating the clock
1573 * once and before iterating over the list to prevent multiple update.
1574 * After the iterative traversal, we need to call rq_clock_stop_loop_update()
1575 * to clear RQCF_ACT_SKIP of rq->clock_update_flags.
1576 */
rq_clock_start_loop_update(struct rq * rq)1577 static inline void rq_clock_start_loop_update(struct rq *rq)
1578 {
1579 lockdep_assert_rq_held(rq);
1580 SCHED_WARN_ON(rq->clock_update_flags & RQCF_ACT_SKIP);
1581 rq->clock_update_flags |= RQCF_ACT_SKIP;
1582 }
1583
rq_clock_stop_loop_update(struct rq * rq)1584 static inline void rq_clock_stop_loop_update(struct rq *rq)
1585 {
1586 lockdep_assert_rq_held(rq);
1587 rq->clock_update_flags &= ~RQCF_ACT_SKIP;
1588 }
1589
1590 struct rq_flags {
1591 unsigned long flags;
1592 struct pin_cookie cookie;
1593 #ifdef CONFIG_SCHED_DEBUG
1594 /*
1595 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1596 * current pin context is stashed here in case it needs to be
1597 * restored in rq_repin_lock().
1598 */
1599 unsigned int clock_update_flags;
1600 #endif
1601 };
1602
1603 extern struct balance_callback balance_push_callback;
1604
1605 /*
1606 * Lockdep annotation that avoids accidental unlocks; it's like a
1607 * sticky/continuous lockdep_assert_held().
1608 *
1609 * This avoids code that has access to 'struct rq *rq' (basically everything in
1610 * the scheduler) from accidentally unlocking the rq if they do not also have a
1611 * copy of the (on-stack) 'struct rq_flags rf'.
1612 *
1613 * Also see Documentation/locking/lockdep-design.rst.
1614 */
rq_pin_lock(struct rq * rq,struct rq_flags * rf)1615 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1616 {
1617 rf->cookie = lockdep_pin_lock(__rq_lockp(rq));
1618
1619 #ifdef CONFIG_SCHED_DEBUG
1620 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1621 rf->clock_update_flags = 0;
1622 #ifdef CONFIG_SMP
1623 SCHED_WARN_ON(rq->balance_callback && rq->balance_callback != &balance_push_callback);
1624 #endif
1625 #endif
1626 }
1627
rq_unpin_lock(struct rq * rq,struct rq_flags * rf)1628 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1629 {
1630 #ifdef CONFIG_SCHED_DEBUG
1631 if (rq->clock_update_flags > RQCF_ACT_SKIP)
1632 rf->clock_update_flags = RQCF_UPDATED;
1633 #endif
1634
1635 lockdep_unpin_lock(__rq_lockp(rq), rf->cookie);
1636 }
1637
rq_repin_lock(struct rq * rq,struct rq_flags * rf)1638 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1639 {
1640 lockdep_repin_lock(__rq_lockp(rq), rf->cookie);
1641
1642 #ifdef CONFIG_SCHED_DEBUG
1643 /*
1644 * Restore the value we stashed in @rf for this pin context.
1645 */
1646 rq->clock_update_flags |= rf->clock_update_flags;
1647 #endif
1648 }
1649
1650 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1651 __acquires(rq->lock);
1652
1653 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1654 __acquires(p->pi_lock)
1655 __acquires(rq->lock);
1656
__task_rq_unlock(struct rq * rq,struct rq_flags * rf)1657 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1658 __releases(rq->lock)
1659 {
1660 rq_unpin_lock(rq, rf);
1661 raw_spin_rq_unlock(rq);
1662 }
1663
1664 static inline void
task_rq_unlock(struct rq * rq,struct task_struct * p,struct rq_flags * rf)1665 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1666 __releases(rq->lock)
1667 __releases(p->pi_lock)
1668 {
1669 rq_unpin_lock(rq, rf);
1670 raw_spin_rq_unlock(rq);
1671 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1672 }
1673
1674 DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct,
1675 _T->rq = task_rq_lock(_T->lock, &_T->rf),
1676 task_rq_unlock(_T->rq, _T->lock, &_T->rf),
1677 struct rq *rq; struct rq_flags rf)
1678
1679 static inline void
rq_lock_irqsave(struct rq * rq,struct rq_flags * rf)1680 rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1681 __acquires(rq->lock)
1682 {
1683 raw_spin_rq_lock_irqsave(rq, rf->flags);
1684 rq_pin_lock(rq, rf);
1685 }
1686
1687 static inline void
rq_lock_irq(struct rq * rq,struct rq_flags * rf)1688 rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1689 __acquires(rq->lock)
1690 {
1691 raw_spin_rq_lock_irq(rq);
1692 rq_pin_lock(rq, rf);
1693 }
1694
1695 static inline void
rq_lock(struct rq * rq,struct rq_flags * rf)1696 rq_lock(struct rq *rq, struct rq_flags *rf)
1697 __acquires(rq->lock)
1698 {
1699 raw_spin_rq_lock(rq);
1700 rq_pin_lock(rq, rf);
1701 }
1702
1703 static inline void
rq_unlock_irqrestore(struct rq * rq,struct rq_flags * rf)1704 rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1705 __releases(rq->lock)
1706 {
1707 rq_unpin_lock(rq, rf);
1708 raw_spin_rq_unlock_irqrestore(rq, rf->flags);
1709 }
1710
1711 static inline void
rq_unlock_irq(struct rq * rq,struct rq_flags * rf)1712 rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1713 __releases(rq->lock)
1714 {
1715 rq_unpin_lock(rq, rf);
1716 raw_spin_rq_unlock_irq(rq);
1717 }
1718
1719 static inline void
rq_unlock(struct rq * rq,struct rq_flags * rf)1720 rq_unlock(struct rq *rq, struct rq_flags *rf)
1721 __releases(rq->lock)
1722 {
1723 rq_unpin_lock(rq, rf);
1724 raw_spin_rq_unlock(rq);
1725 }
1726
1727 DEFINE_LOCK_GUARD_1(rq_lock, struct rq,
1728 rq_lock(_T->lock, &_T->rf),
1729 rq_unlock(_T->lock, &_T->rf),
1730 struct rq_flags rf)
1731
1732 DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq,
1733 rq_lock_irq(_T->lock, &_T->rf),
1734 rq_unlock_irq(_T->lock, &_T->rf),
1735 struct rq_flags rf)
1736
1737 DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq,
1738 rq_lock_irqsave(_T->lock, &_T->rf),
1739 rq_unlock_irqrestore(_T->lock, &_T->rf),
1740 struct rq_flags rf)
1741
1742 static inline struct rq *
this_rq_lock_irq(struct rq_flags * rf)1743 this_rq_lock_irq(struct rq_flags *rf)
1744 __acquires(rq->lock)
1745 {
1746 struct rq *rq;
1747
1748 local_irq_disable();
1749 rq = this_rq();
1750 rq_lock(rq, rf);
1751 return rq;
1752 }
1753
1754 #ifdef CONFIG_NUMA
1755 enum numa_topology_type {
1756 NUMA_DIRECT,
1757 NUMA_GLUELESS_MESH,
1758 NUMA_BACKPLANE,
1759 };
1760 extern enum numa_topology_type sched_numa_topology_type;
1761 extern int sched_max_numa_distance;
1762 extern bool find_numa_distance(int distance);
1763 extern void sched_init_numa(int offline_node);
1764 extern void sched_update_numa(int cpu, bool online);
1765 extern void sched_domains_numa_masks_set(unsigned int cpu);
1766 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1767 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1768 #else
sched_init_numa(int offline_node)1769 static inline void sched_init_numa(int offline_node) { }
sched_update_numa(int cpu,bool online)1770 static inline void sched_update_numa(int cpu, bool online) { }
sched_domains_numa_masks_set(unsigned int cpu)1771 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
sched_domains_numa_masks_clear(unsigned int cpu)1772 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
sched_numa_find_closest(const struct cpumask * cpus,int cpu)1773 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1774 {
1775 return nr_cpu_ids;
1776 }
1777 #endif
1778
1779 #ifdef CONFIG_NUMA_BALANCING
1780 /* The regions in numa_faults array from task_struct */
1781 enum numa_faults_stats {
1782 NUMA_MEM = 0,
1783 NUMA_CPU,
1784 NUMA_MEMBUF,
1785 NUMA_CPUBUF
1786 };
1787 extern void sched_setnuma(struct task_struct *p, int node);
1788 extern int migrate_task_to(struct task_struct *p, int cpu);
1789 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1790 int cpu, int scpu);
1791 extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1792 #else
1793 static inline void
init_numa_balancing(unsigned long clone_flags,struct task_struct * p)1794 init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1795 {
1796 }
1797 #endif /* CONFIG_NUMA_BALANCING */
1798
1799 #ifdef CONFIG_SMP
1800
1801 static inline void
queue_balance_callback(struct rq * rq,struct balance_callback * head,void (* func)(struct rq * rq))1802 queue_balance_callback(struct rq *rq,
1803 struct balance_callback *head,
1804 void (*func)(struct rq *rq))
1805 {
1806 lockdep_assert_rq_held(rq);
1807
1808 /*
1809 * Don't (re)queue an already queued item; nor queue anything when
1810 * balance_push() is active, see the comment with
1811 * balance_push_callback.
1812 */
1813 if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
1814 return;
1815
1816 head->func = func;
1817 head->next = rq->balance_callback;
1818 rq->balance_callback = head;
1819 }
1820
1821 #define rcu_dereference_check_sched_domain(p) \
1822 rcu_dereference_check((p), \
1823 lockdep_is_held(&sched_domains_mutex))
1824
1825 /*
1826 * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1827 * See destroy_sched_domains: call_rcu for details.
1828 *
1829 * The domain tree of any CPU may only be accessed from within
1830 * preempt-disabled sections.
1831 */
1832 #define for_each_domain(cpu, __sd) \
1833 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1834 __sd; __sd = __sd->parent)
1835
1836 /* A mask of all the SD flags that have the SDF_SHARED_CHILD metaflag */
1837 #define SD_FLAG(name, mflags) (name * !!((mflags) & SDF_SHARED_CHILD)) |
1838 static const unsigned int SD_SHARED_CHILD_MASK =
1839 #include <linux/sched/sd_flags.h>
1840 0;
1841 #undef SD_FLAG
1842
1843 /**
1844 * highest_flag_domain - Return highest sched_domain containing flag.
1845 * @cpu: The CPU whose highest level of sched domain is to
1846 * be returned.
1847 * @flag: The flag to check for the highest sched_domain
1848 * for the given CPU.
1849 *
1850 * Returns the highest sched_domain of a CPU which contains @flag. If @flag has
1851 * the SDF_SHARED_CHILD metaflag, all the children domains also have @flag.
1852 */
highest_flag_domain(int cpu,int flag)1853 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1854 {
1855 struct sched_domain *sd, *hsd = NULL;
1856
1857 for_each_domain(cpu, sd) {
1858 if (sd->flags & flag) {
1859 hsd = sd;
1860 continue;
1861 }
1862
1863 /*
1864 * Stop the search if @flag is known to be shared at lower
1865 * levels. It will not be found further up.
1866 */
1867 if (flag & SD_SHARED_CHILD_MASK)
1868 break;
1869 }
1870
1871 return hsd;
1872 }
1873
lowest_flag_domain(int cpu,int flag)1874 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1875 {
1876 struct sched_domain *sd;
1877
1878 for_each_domain(cpu, sd) {
1879 if (sd->flags & flag)
1880 break;
1881 }
1882
1883 return sd;
1884 }
1885
1886 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
1887 DECLARE_PER_CPU(int, sd_llc_size);
1888 DECLARE_PER_CPU(int, sd_llc_id);
1889 DECLARE_PER_CPU(int, sd_share_id);
1890 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
1891 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
1892 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
1893 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
1894 extern struct static_key_false sched_asym_cpucapacity;
1895 extern struct static_key_false sched_cluster_active;
1896
sched_asym_cpucap_active(void)1897 static __always_inline bool sched_asym_cpucap_active(void)
1898 {
1899 return static_branch_unlikely(&sched_asym_cpucapacity);
1900 }
1901
1902 struct sched_group_capacity {
1903 atomic_t ref;
1904 /*
1905 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
1906 * for a single CPU.
1907 */
1908 unsigned long capacity;
1909 unsigned long min_capacity; /* Min per-CPU capacity in group */
1910 unsigned long max_capacity; /* Max per-CPU capacity in group */
1911 unsigned long next_update;
1912 int imbalance; /* XXX unrelated to capacity but shared group state */
1913
1914 #ifdef CONFIG_SCHED_DEBUG
1915 int id;
1916 #endif
1917
1918 unsigned long cpumask[]; /* Balance mask */
1919 };
1920
1921 struct sched_group {
1922 struct sched_group *next; /* Must be a circular list */
1923 atomic_t ref;
1924
1925 unsigned int group_weight;
1926 unsigned int cores;
1927 struct sched_group_capacity *sgc;
1928 int asym_prefer_cpu; /* CPU of highest priority in group */
1929 int flags;
1930
1931 /*
1932 * The CPUs this group covers.
1933 *
1934 * NOTE: this field is variable length. (Allocated dynamically
1935 * by attaching extra space to the end of the structure,
1936 * depending on how many CPUs the kernel has booted up with)
1937 */
1938 unsigned long cpumask[];
1939 };
1940
sched_group_span(struct sched_group * sg)1941 static inline struct cpumask *sched_group_span(struct sched_group *sg)
1942 {
1943 return to_cpumask(sg->cpumask);
1944 }
1945
1946 /*
1947 * See build_balance_mask().
1948 */
group_balance_mask(struct sched_group * sg)1949 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
1950 {
1951 return to_cpumask(sg->sgc->cpumask);
1952 }
1953
1954 extern int group_balance_cpu(struct sched_group *sg);
1955
1956 #ifdef CONFIG_SCHED_DEBUG
1957 void update_sched_domain_debugfs(void);
1958 void dirty_sched_domain_sysctl(int cpu);
1959 #else
update_sched_domain_debugfs(void)1960 static inline void update_sched_domain_debugfs(void)
1961 {
1962 }
dirty_sched_domain_sysctl(int cpu)1963 static inline void dirty_sched_domain_sysctl(int cpu)
1964 {
1965 }
1966 #endif
1967
1968 extern int sched_update_scaling(void);
1969
task_user_cpus(struct task_struct * p)1970 static inline const struct cpumask *task_user_cpus(struct task_struct *p)
1971 {
1972 if (!p->user_cpus_ptr)
1973 return cpu_possible_mask; /* &init_task.cpus_mask */
1974 return p->user_cpus_ptr;
1975 }
1976 #endif /* CONFIG_SMP */
1977
1978 #include "stats.h"
1979
1980 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS)
1981
1982 extern void __sched_core_account_forceidle(struct rq *rq);
1983
sched_core_account_forceidle(struct rq * rq)1984 static inline void sched_core_account_forceidle(struct rq *rq)
1985 {
1986 if (schedstat_enabled())
1987 __sched_core_account_forceidle(rq);
1988 }
1989
1990 extern void __sched_core_tick(struct rq *rq);
1991
sched_core_tick(struct rq * rq)1992 static inline void sched_core_tick(struct rq *rq)
1993 {
1994 if (sched_core_enabled(rq) && schedstat_enabled())
1995 __sched_core_tick(rq);
1996 }
1997
1998 #else
1999
sched_core_account_forceidle(struct rq * rq)2000 static inline void sched_core_account_forceidle(struct rq *rq) {}
2001
sched_core_tick(struct rq * rq)2002 static inline void sched_core_tick(struct rq *rq) {}
2003
2004 #endif /* CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS */
2005
2006 #ifdef CONFIG_CGROUP_SCHED
2007
2008 /*
2009 * Return the group to which this tasks belongs.
2010 *
2011 * We cannot use task_css() and friends because the cgroup subsystem
2012 * changes that value before the cgroup_subsys::attach() method is called,
2013 * therefore we cannot pin it and might observe the wrong value.
2014 *
2015 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
2016 * core changes this before calling sched_move_task().
2017 *
2018 * Instead we use a 'copy' which is updated from sched_move_task() while
2019 * holding both task_struct::pi_lock and rq::lock.
2020 */
task_group(struct task_struct * p)2021 static inline struct task_group *task_group(struct task_struct *p)
2022 {
2023 return p->sched_task_group;
2024 }
2025
2026 /* 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)2027 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
2028 {
2029 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
2030 struct task_group *tg = task_group(p);
2031 #endif
2032
2033 #ifdef CONFIG_FAIR_GROUP_SCHED
2034 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
2035 p->se.cfs_rq = tg->cfs_rq[cpu];
2036 p->se.parent = tg->se[cpu];
2037 p->se.depth = tg->se[cpu] ? tg->se[cpu]->depth + 1 : 0;
2038 #endif
2039
2040 #ifdef CONFIG_RT_GROUP_SCHED
2041 p->rt.rt_rq = tg->rt_rq[cpu];
2042 p->rt.parent = tg->rt_se[cpu];
2043 #endif
2044 }
2045
2046 #else /* CONFIG_CGROUP_SCHED */
2047
set_task_rq(struct task_struct * p,unsigned int cpu)2048 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
task_group(struct task_struct * p)2049 static inline struct task_group *task_group(struct task_struct *p)
2050 {
2051 return NULL;
2052 }
2053
2054 #endif /* CONFIG_CGROUP_SCHED */
2055
__set_task_cpu(struct task_struct * p,unsigned int cpu)2056 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
2057 {
2058 set_task_rq(p, cpu);
2059 #ifdef CONFIG_SMP
2060 /*
2061 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
2062 * successfully executed on another CPU. We must ensure that updates of
2063 * per-task data have been completed by this moment.
2064 */
2065 smp_wmb();
2066 WRITE_ONCE(task_thread_info(p)->cpu, cpu);
2067 p->wake_cpu = cpu;
2068 #endif
2069 }
2070
2071 /*
2072 * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
2073 */
2074 #ifdef CONFIG_SCHED_DEBUG
2075 # define const_debug __read_mostly
2076 #else
2077 # define const_debug const
2078 #endif
2079
2080 #define SCHED_FEAT(name, enabled) \
2081 __SCHED_FEAT_##name ,
2082
2083 enum {
2084 #include "features.h"
2085 __SCHED_FEAT_NR,
2086 };
2087
2088 #undef SCHED_FEAT
2089
2090 #ifdef CONFIG_SCHED_DEBUG
2091
2092 /*
2093 * To support run-time toggling of sched features, all the translation units
2094 * (but core.c) reference the sysctl_sched_features defined in core.c.
2095 */
2096 extern const_debug unsigned int sysctl_sched_features;
2097
2098 #ifdef CONFIG_JUMP_LABEL
2099 #define SCHED_FEAT(name, enabled) \
2100 static __always_inline bool static_branch_##name(struct static_key *key) \
2101 { \
2102 return static_key_##enabled(key); \
2103 }
2104
2105 #include "features.h"
2106 #undef SCHED_FEAT
2107
2108 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
2109 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
2110
2111 #else /* !CONFIG_JUMP_LABEL */
2112
2113 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2114
2115 #endif /* CONFIG_JUMP_LABEL */
2116
2117 #else /* !SCHED_DEBUG */
2118
2119 /*
2120 * Each translation unit has its own copy of sysctl_sched_features to allow
2121 * constants propagation at compile time and compiler optimization based on
2122 * features default.
2123 */
2124 #define SCHED_FEAT(name, enabled) \
2125 (1UL << __SCHED_FEAT_##name) * enabled |
2126 static const_debug __maybe_unused unsigned int sysctl_sched_features =
2127 #include "features.h"
2128 0;
2129 #undef SCHED_FEAT
2130
2131 #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2132
2133 #endif /* SCHED_DEBUG */
2134
2135 extern struct static_key_false sched_numa_balancing;
2136 extern struct static_key_false sched_schedstats;
2137
global_rt_period(void)2138 static inline u64 global_rt_period(void)
2139 {
2140 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
2141 }
2142
global_rt_runtime(void)2143 static inline u64 global_rt_runtime(void)
2144 {
2145 if (sysctl_sched_rt_runtime < 0)
2146 return RUNTIME_INF;
2147
2148 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
2149 }
2150
task_current(struct rq * rq,struct task_struct * p)2151 static inline int task_current(struct rq *rq, struct task_struct *p)
2152 {
2153 return rq->curr == p;
2154 }
2155
task_on_cpu(struct rq * rq,struct task_struct * p)2156 static inline int task_on_cpu(struct rq *rq, struct task_struct *p)
2157 {
2158 #ifdef CONFIG_SMP
2159 return p->on_cpu;
2160 #else
2161 return task_current(rq, p);
2162 #endif
2163 }
2164
task_on_rq_queued(struct task_struct * p)2165 static inline int task_on_rq_queued(struct task_struct *p)
2166 {
2167 return p->on_rq == TASK_ON_RQ_QUEUED;
2168 }
2169
task_on_rq_migrating(struct task_struct * p)2170 static inline int task_on_rq_migrating(struct task_struct *p)
2171 {
2172 return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
2173 }
2174
2175 /* Wake flags. The first three directly map to some SD flag value */
2176 #define WF_EXEC 0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
2177 #define WF_FORK 0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
2178 #define WF_TTWU 0x08 /* Wakeup; maps to SD_BALANCE_WAKE */
2179
2180 #define WF_SYNC 0x10 /* Waker goes to sleep after wakeup */
2181 #define WF_MIGRATED 0x20 /* Internal use, task got migrated */
2182 #define WF_CURRENT_CPU 0x40 /* Prefer to move the wakee to the current CPU. */
2183
2184 #ifdef CONFIG_SMP
2185 static_assert(WF_EXEC == SD_BALANCE_EXEC);
2186 static_assert(WF_FORK == SD_BALANCE_FORK);
2187 static_assert(WF_TTWU == SD_BALANCE_WAKE);
2188 #endif
2189
2190 /*
2191 * To aid in avoiding the subversion of "niceness" due to uneven distribution
2192 * of tasks with abnormal "nice" values across CPUs the contribution that
2193 * each task makes to its run queue's load is weighted according to its
2194 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
2195 * scaled version of the new time slice allocation that they receive on time
2196 * slice expiry etc.
2197 */
2198
2199 #define WEIGHT_IDLEPRIO 3
2200 #define WMULT_IDLEPRIO 1431655765
2201
2202 extern const int sched_prio_to_weight[40];
2203 extern const u32 sched_prio_to_wmult[40];
2204
2205 /*
2206 * {de,en}queue flags:
2207 *
2208 * DEQUEUE_SLEEP - task is no longer runnable
2209 * ENQUEUE_WAKEUP - task just became runnable
2210 *
2211 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
2212 * are in a known state which allows modification. Such pairs
2213 * should preserve as much state as possible.
2214 *
2215 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
2216 * in the runqueue.
2217 *
2218 * NOCLOCK - skip the update_rq_clock() (avoids double updates)
2219 *
2220 * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE)
2221 *
2222 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified)
2223 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
2224 * ENQUEUE_MIGRATED - the task was migrated during wakeup
2225 *
2226 */
2227
2228 #define DEQUEUE_SLEEP 0x01
2229 #define DEQUEUE_SAVE 0x02 /* Matches ENQUEUE_RESTORE */
2230 #define DEQUEUE_MOVE 0x04 /* Matches ENQUEUE_MOVE */
2231 #define DEQUEUE_NOCLOCK 0x08 /* Matches ENQUEUE_NOCLOCK */
2232 #define DEQUEUE_MIGRATING 0x100 /* Matches ENQUEUE_MIGRATING */
2233
2234 #define ENQUEUE_WAKEUP 0x01
2235 #define ENQUEUE_RESTORE 0x02
2236 #define ENQUEUE_MOVE 0x04
2237 #define ENQUEUE_NOCLOCK 0x08
2238
2239 #define ENQUEUE_HEAD 0x10
2240 #define ENQUEUE_REPLENISH 0x20
2241 #ifdef CONFIG_SMP
2242 #define ENQUEUE_MIGRATED 0x40
2243 #else
2244 #define ENQUEUE_MIGRATED 0x00
2245 #endif
2246 #define ENQUEUE_INITIAL 0x80
2247 #define ENQUEUE_MIGRATING 0x100
2248
2249 #define RETRY_TASK ((void *)-1UL)
2250
2251 struct affinity_context {
2252 const struct cpumask *new_mask;
2253 struct cpumask *user_mask;
2254 unsigned int flags;
2255 };
2256
2257 extern s64 update_curr_common(struct rq *rq);
2258
2259 struct sched_class {
2260
2261 #ifdef CONFIG_UCLAMP_TASK
2262 int uclamp_enabled;
2263 #endif
2264
2265 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
2266 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
2267 void (*yield_task) (struct rq *rq);
2268 bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
2269
2270 void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags);
2271
2272 struct task_struct *(*pick_next_task)(struct rq *rq);
2273
2274 void (*put_prev_task)(struct rq *rq, struct task_struct *p);
2275 void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
2276
2277 #ifdef CONFIG_SMP
2278 int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2279 int (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
2280
2281 struct task_struct * (*pick_task)(struct rq *rq);
2282
2283 void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
2284
2285 void (*task_woken)(struct rq *this_rq, struct task_struct *task);
2286
2287 void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx);
2288
2289 void (*rq_online)(struct rq *rq);
2290 void (*rq_offline)(struct rq *rq);
2291
2292 struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
2293 #endif
2294
2295 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
2296 void (*task_fork)(struct task_struct *p);
2297 void (*task_dead)(struct task_struct *p);
2298
2299 /*
2300 * The switched_from() call is allowed to drop rq->lock, therefore we
2301 * cannot assume the switched_from/switched_to pair is serialized by
2302 * rq->lock. They are however serialized by p->pi_lock.
2303 */
2304 void (*switched_from)(struct rq *this_rq, struct task_struct *task);
2305 void (*switched_to) (struct rq *this_rq, struct task_struct *task);
2306 void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
2307 int oldprio);
2308
2309 unsigned int (*get_rr_interval)(struct rq *rq,
2310 struct task_struct *task);
2311
2312 void (*update_curr)(struct rq *rq);
2313
2314 #ifdef CONFIG_FAIR_GROUP_SCHED
2315 void (*task_change_group)(struct task_struct *p);
2316 #endif
2317
2318 #ifdef CONFIG_SCHED_CORE
2319 int (*task_is_throttled)(struct task_struct *p, int cpu);
2320 #endif
2321 };
2322
put_prev_task(struct rq * rq,struct task_struct * prev)2323 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
2324 {
2325 WARN_ON_ONCE(rq->curr != prev);
2326 prev->sched_class->put_prev_task(rq, prev);
2327 }
2328
set_next_task(struct rq * rq,struct task_struct * next)2329 static inline void set_next_task(struct rq *rq, struct task_struct *next)
2330 {
2331 next->sched_class->set_next_task(rq, next, false);
2332 }
2333
2334
2335 /*
2336 * Helper to define a sched_class instance; each one is placed in a separate
2337 * section which is ordered by the linker script:
2338 *
2339 * include/asm-generic/vmlinux.lds.h
2340 *
2341 * *CAREFUL* they are laid out in *REVERSE* order!!!
2342 *
2343 * Also enforce alignment on the instance, not the type, to guarantee layout.
2344 */
2345 #define DEFINE_SCHED_CLASS(name) \
2346 const struct sched_class name##_sched_class \
2347 __aligned(__alignof__(struct sched_class)) \
2348 __section("__" #name "_sched_class")
2349
2350 /* Defined in include/asm-generic/vmlinux.lds.h */
2351 extern struct sched_class __sched_class_highest[];
2352 extern struct sched_class __sched_class_lowest[];
2353
2354 #define for_class_range(class, _from, _to) \
2355 for (class = (_from); class < (_to); class++)
2356
2357 #define for_each_class(class) \
2358 for_class_range(class, __sched_class_highest, __sched_class_lowest)
2359
2360 #define sched_class_above(_a, _b) ((_a) < (_b))
2361
2362 extern const struct sched_class stop_sched_class;
2363 extern const struct sched_class dl_sched_class;
2364 extern const struct sched_class rt_sched_class;
2365 extern const struct sched_class fair_sched_class;
2366 extern const struct sched_class idle_sched_class;
2367
sched_stop_runnable(struct rq * rq)2368 static inline bool sched_stop_runnable(struct rq *rq)
2369 {
2370 return rq->stop && task_on_rq_queued(rq->stop);
2371 }
2372
sched_dl_runnable(struct rq * rq)2373 static inline bool sched_dl_runnable(struct rq *rq)
2374 {
2375 return rq->dl.dl_nr_running > 0;
2376 }
2377
sched_rt_runnable(struct rq * rq)2378 static inline bool sched_rt_runnable(struct rq *rq)
2379 {
2380 return rq->rt.rt_queued > 0;
2381 }
2382
sched_fair_runnable(struct rq * rq)2383 static inline bool sched_fair_runnable(struct rq *rq)
2384 {
2385 return rq->cfs.nr_running > 0;
2386 }
2387
2388 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2389 extern struct task_struct *pick_next_task_idle(struct rq *rq);
2390
2391 #define SCA_CHECK 0x01
2392 #define SCA_MIGRATE_DISABLE 0x02
2393 #define SCA_MIGRATE_ENABLE 0x04
2394 #define SCA_USER 0x08
2395
2396 #ifdef CONFIG_SMP
2397
2398 extern void update_group_capacity(struct sched_domain *sd, int cpu);
2399
2400 extern void trigger_load_balance(struct rq *rq);
2401
2402 extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx);
2403
get_push_task(struct rq * rq)2404 static inline struct task_struct *get_push_task(struct rq *rq)
2405 {
2406 struct task_struct *p = rq->curr;
2407
2408 lockdep_assert_rq_held(rq);
2409
2410 if (rq->push_busy)
2411 return NULL;
2412
2413 if (p->nr_cpus_allowed == 1)
2414 return NULL;
2415
2416 if (p->migration_disabled)
2417 return NULL;
2418
2419 rq->push_busy = true;
2420 return get_task_struct(p);
2421 }
2422
2423 extern int push_cpu_stop(void *arg);
2424
2425 #endif
2426
2427 #ifdef CONFIG_CPU_IDLE
idle_set_state(struct rq * rq,struct cpuidle_state * idle_state)2428 static inline void idle_set_state(struct rq *rq,
2429 struct cpuidle_state *idle_state)
2430 {
2431 rq->idle_state = idle_state;
2432 }
2433
idle_get_state(struct rq * rq)2434 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2435 {
2436 SCHED_WARN_ON(!rcu_read_lock_held());
2437
2438 return rq->idle_state;
2439 }
2440 #else
idle_set_state(struct rq * rq,struct cpuidle_state * idle_state)2441 static inline void idle_set_state(struct rq *rq,
2442 struct cpuidle_state *idle_state)
2443 {
2444 }
2445
idle_get_state(struct rq * rq)2446 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2447 {
2448 return NULL;
2449 }
2450 #endif
2451
2452 extern void schedule_idle(void);
2453 asmlinkage void schedule_user(void);
2454
2455 extern void sysrq_sched_debug_show(void);
2456 extern void sched_init_granularity(void);
2457 extern void update_max_interval(void);
2458
2459 extern void init_sched_dl_class(void);
2460 extern void init_sched_rt_class(void);
2461 extern void init_sched_fair_class(void);
2462
2463 extern void reweight_task(struct task_struct *p, int prio);
2464
2465 extern void resched_curr(struct rq *rq);
2466 extern void resched_cpu(int cpu);
2467
2468 extern struct rt_bandwidth def_rt_bandwidth;
2469 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
2470 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq);
2471
2472 extern void init_dl_entity(struct sched_dl_entity *dl_se);
2473
2474 #define BW_SHIFT 20
2475 #define BW_UNIT (1 << BW_SHIFT)
2476 #define RATIO_SHIFT 8
2477 #define MAX_BW_BITS (64 - BW_SHIFT)
2478 #define MAX_BW ((1ULL << MAX_BW_BITS) - 1)
2479 unsigned long to_ratio(u64 period, u64 runtime);
2480
2481 extern void init_entity_runnable_average(struct sched_entity *se);
2482 extern void post_init_entity_util_avg(struct task_struct *p);
2483
2484 #ifdef CONFIG_NO_HZ_FULL
2485 extern bool sched_can_stop_tick(struct rq *rq);
2486 extern int __init sched_tick_offload_init(void);
2487
2488 /*
2489 * Tick may be needed by tasks in the runqueue depending on their policy and
2490 * requirements. If tick is needed, lets send the target an IPI to kick it out of
2491 * nohz mode if necessary.
2492 */
sched_update_tick_dependency(struct rq * rq)2493 static inline void sched_update_tick_dependency(struct rq *rq)
2494 {
2495 int cpu = cpu_of(rq);
2496
2497 if (!tick_nohz_full_cpu(cpu))
2498 return;
2499
2500 if (sched_can_stop_tick(rq))
2501 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
2502 else
2503 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
2504 }
2505 #else
sched_tick_offload_init(void)2506 static inline int sched_tick_offload_init(void) { return 0; }
sched_update_tick_dependency(struct rq * rq)2507 static inline void sched_update_tick_dependency(struct rq *rq) { }
2508 #endif
2509
add_nr_running(struct rq * rq,unsigned count)2510 static inline void add_nr_running(struct rq *rq, unsigned count)
2511 {
2512 unsigned prev_nr = rq->nr_running;
2513
2514 rq->nr_running = prev_nr + count;
2515 if (trace_sched_update_nr_running_tp_enabled()) {
2516 call_trace_sched_update_nr_running(rq, count);
2517 }
2518
2519 #ifdef CONFIG_SMP
2520 if (prev_nr < 2 && rq->nr_running >= 2) {
2521 if (!READ_ONCE(rq->rd->overload))
2522 WRITE_ONCE(rq->rd->overload, 1);
2523 }
2524 #endif
2525
2526 sched_update_tick_dependency(rq);
2527 }
2528
sub_nr_running(struct rq * rq,unsigned count)2529 static inline void sub_nr_running(struct rq *rq, unsigned count)
2530 {
2531 rq->nr_running -= count;
2532 if (trace_sched_update_nr_running_tp_enabled()) {
2533 call_trace_sched_update_nr_running(rq, -count);
2534 }
2535
2536 /* Check if we still need preemption */
2537 sched_update_tick_dependency(rq);
2538 }
2539
2540 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
2541 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
2542
2543 extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags);
2544
2545 #ifdef CONFIG_PREEMPT_RT
2546 #define SCHED_NR_MIGRATE_BREAK 8
2547 #else
2548 #define SCHED_NR_MIGRATE_BREAK 32
2549 #endif
2550
2551 extern const_debug unsigned int sysctl_sched_nr_migrate;
2552 extern const_debug unsigned int sysctl_sched_migration_cost;
2553
2554 extern unsigned int sysctl_sched_base_slice;
2555
2556 #ifdef CONFIG_SCHED_DEBUG
2557 extern int sysctl_resched_latency_warn_ms;
2558 extern int sysctl_resched_latency_warn_once;
2559
2560 extern unsigned int sysctl_sched_tunable_scaling;
2561
2562 extern unsigned int sysctl_numa_balancing_scan_delay;
2563 extern unsigned int sysctl_numa_balancing_scan_period_min;
2564 extern unsigned int sysctl_numa_balancing_scan_period_max;
2565 extern unsigned int sysctl_numa_balancing_scan_size;
2566 extern unsigned int sysctl_numa_balancing_hot_threshold;
2567 #endif
2568
2569 #ifdef CONFIG_SCHED_HRTICK
2570
2571 /*
2572 * Use hrtick when:
2573 * - enabled by features
2574 * - hrtimer is actually high res
2575 */
hrtick_enabled(struct rq * rq)2576 static inline int hrtick_enabled(struct rq *rq)
2577 {
2578 if (!cpu_active(cpu_of(rq)))
2579 return 0;
2580 return hrtimer_is_hres_active(&rq->hrtick_timer);
2581 }
2582
hrtick_enabled_fair(struct rq * rq)2583 static inline int hrtick_enabled_fair(struct rq *rq)
2584 {
2585 if (!sched_feat(HRTICK))
2586 return 0;
2587 return hrtick_enabled(rq);
2588 }
2589
hrtick_enabled_dl(struct rq * rq)2590 static inline int hrtick_enabled_dl(struct rq *rq)
2591 {
2592 if (!sched_feat(HRTICK_DL))
2593 return 0;
2594 return hrtick_enabled(rq);
2595 }
2596
2597 void hrtick_start(struct rq *rq, u64 delay);
2598
2599 #else
2600
hrtick_enabled_fair(struct rq * rq)2601 static inline int hrtick_enabled_fair(struct rq *rq)
2602 {
2603 return 0;
2604 }
2605
hrtick_enabled_dl(struct rq * rq)2606 static inline int hrtick_enabled_dl(struct rq *rq)
2607 {
2608 return 0;
2609 }
2610
hrtick_enabled(struct rq * rq)2611 static inline int hrtick_enabled(struct rq *rq)
2612 {
2613 return 0;
2614 }
2615
2616 #endif /* CONFIG_SCHED_HRTICK */
2617
2618 #ifndef arch_scale_freq_tick
2619 static __always_inline
arch_scale_freq_tick(void)2620 void arch_scale_freq_tick(void)
2621 {
2622 }
2623 #endif
2624
2625 #ifndef arch_scale_freq_capacity
2626 /**
2627 * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
2628 * @cpu: the CPU in question.
2629 *
2630 * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
2631 *
2632 * f_curr
2633 * ------ * SCHED_CAPACITY_SCALE
2634 * f_max
2635 */
2636 static __always_inline
arch_scale_freq_capacity(int cpu)2637 unsigned long arch_scale_freq_capacity(int cpu)
2638 {
2639 return SCHED_CAPACITY_SCALE;
2640 }
2641 #endif
2642
2643 #ifdef CONFIG_SCHED_DEBUG
2644 /*
2645 * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to
2646 * acquire rq lock instead of rq_lock(). So at the end of these two functions
2647 * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of
2648 * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning.
2649 */
double_rq_clock_clear_update(struct rq * rq1,struct rq * rq2)2650 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2)
2651 {
2652 rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
2653 /* rq1 == rq2 for !CONFIG_SMP, so just clear RQCF_UPDATED once. */
2654 #ifdef CONFIG_SMP
2655 rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
2656 #endif
2657 }
2658 #else
double_rq_clock_clear_update(struct rq * rq1,struct rq * rq2)2659 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2) {}
2660 #endif
2661
2662 #define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...) \
2663 __DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__) \
2664 static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2) \
2665 { class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t; \
2666 _lock; return _t; }
2667
2668 #ifdef CONFIG_SMP
2669
rq_order_less(struct rq * rq1,struct rq * rq2)2670 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2)
2671 {
2672 #ifdef CONFIG_SCHED_CORE
2673 /*
2674 * In order to not have {0,2},{1,3} turn into into an AB-BA,
2675 * order by core-id first and cpu-id second.
2676 *
2677 * Notably:
2678 *
2679 * double_rq_lock(0,3); will take core-0, core-1 lock
2680 * double_rq_lock(1,2); will take core-1, core-0 lock
2681 *
2682 * when only cpu-id is considered.
2683 */
2684 if (rq1->core->cpu < rq2->core->cpu)
2685 return true;
2686 if (rq1->core->cpu > rq2->core->cpu)
2687 return false;
2688
2689 /*
2690 * __sched_core_flip() relies on SMT having cpu-id lock order.
2691 */
2692 #endif
2693 return rq1->cpu < rq2->cpu;
2694 }
2695
2696 extern void double_rq_lock(struct rq *rq1, struct rq *rq2);
2697
2698 #ifdef CONFIG_PREEMPTION
2699
2700 /*
2701 * fair double_lock_balance: Safely acquires both rq->locks in a fair
2702 * way at the expense of forcing extra atomic operations in all
2703 * invocations. This assures that the double_lock is acquired using the
2704 * same underlying policy as the spinlock_t on this architecture, which
2705 * reduces latency compared to the unfair variant below. However, it
2706 * also adds more overhead and therefore may reduce throughput.
2707 */
_double_lock_balance(struct rq * this_rq,struct rq * busiest)2708 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2709 __releases(this_rq->lock)
2710 __acquires(busiest->lock)
2711 __acquires(this_rq->lock)
2712 {
2713 raw_spin_rq_unlock(this_rq);
2714 double_rq_lock(this_rq, busiest);
2715
2716 return 1;
2717 }
2718
2719 #else
2720 /*
2721 * Unfair double_lock_balance: Optimizes throughput at the expense of
2722 * latency by eliminating extra atomic operations when the locks are
2723 * already in proper order on entry. This favors lower CPU-ids and will
2724 * grant the double lock to lower CPUs over higher ids under contention,
2725 * regardless of entry order into the function.
2726 */
_double_lock_balance(struct rq * this_rq,struct rq * busiest)2727 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2728 __releases(this_rq->lock)
2729 __acquires(busiest->lock)
2730 __acquires(this_rq->lock)
2731 {
2732 if (__rq_lockp(this_rq) == __rq_lockp(busiest) ||
2733 likely(raw_spin_rq_trylock(busiest))) {
2734 double_rq_clock_clear_update(this_rq, busiest);
2735 return 0;
2736 }
2737
2738 if (rq_order_less(this_rq, busiest)) {
2739 raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING);
2740 double_rq_clock_clear_update(this_rq, busiest);
2741 return 0;
2742 }
2743
2744 raw_spin_rq_unlock(this_rq);
2745 double_rq_lock(this_rq, busiest);
2746
2747 return 1;
2748 }
2749
2750 #endif /* CONFIG_PREEMPTION */
2751
2752 /*
2753 * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
2754 */
double_lock_balance(struct rq * this_rq,struct rq * busiest)2755 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
2756 {
2757 lockdep_assert_irqs_disabled();
2758
2759 return _double_lock_balance(this_rq, busiest);
2760 }
2761
double_unlock_balance(struct rq * this_rq,struct rq * busiest)2762 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
2763 __releases(busiest->lock)
2764 {
2765 if (__rq_lockp(this_rq) != __rq_lockp(busiest))
2766 raw_spin_rq_unlock(busiest);
2767 lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_);
2768 }
2769
double_lock(spinlock_t * l1,spinlock_t * l2)2770 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
2771 {
2772 if (l1 > l2)
2773 swap(l1, l2);
2774
2775 spin_lock(l1);
2776 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2777 }
2778
double_lock_irq(spinlock_t * l1,spinlock_t * l2)2779 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
2780 {
2781 if (l1 > l2)
2782 swap(l1, l2);
2783
2784 spin_lock_irq(l1);
2785 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2786 }
2787
double_raw_lock(raw_spinlock_t * l1,raw_spinlock_t * l2)2788 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
2789 {
2790 if (l1 > l2)
2791 swap(l1, l2);
2792
2793 raw_spin_lock(l1);
2794 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2795 }
2796
double_raw_unlock(raw_spinlock_t * l1,raw_spinlock_t * l2)2797 static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2)
2798 {
2799 raw_spin_unlock(l1);
2800 raw_spin_unlock(l2);
2801 }
2802
2803 DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t,
2804 double_raw_lock(_T->lock, _T->lock2),
2805 double_raw_unlock(_T->lock, _T->lock2))
2806
2807 /*
2808 * double_rq_unlock - safely unlock two runqueues
2809 *
2810 * Note this does not restore interrupts like task_rq_unlock,
2811 * you need to do so manually after calling.
2812 */
double_rq_unlock(struct rq * rq1,struct rq * rq2)2813 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2814 __releases(rq1->lock)
2815 __releases(rq2->lock)
2816 {
2817 if (__rq_lockp(rq1) != __rq_lockp(rq2))
2818 raw_spin_rq_unlock(rq2);
2819 else
2820 __release(rq2->lock);
2821 raw_spin_rq_unlock(rq1);
2822 }
2823
2824 extern void set_rq_online (struct rq *rq);
2825 extern void set_rq_offline(struct rq *rq);
2826 extern bool sched_smp_initialized;
2827
2828 #else /* CONFIG_SMP */
2829
2830 /*
2831 * double_rq_lock - safely lock two runqueues
2832 *
2833 * Note this does not disable interrupts like task_rq_lock,
2834 * you need to do so manually before calling.
2835 */
double_rq_lock(struct rq * rq1,struct rq * rq2)2836 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2837 __acquires(rq1->lock)
2838 __acquires(rq2->lock)
2839 {
2840 WARN_ON_ONCE(!irqs_disabled());
2841 WARN_ON_ONCE(rq1 != rq2);
2842 raw_spin_rq_lock(rq1);
2843 __acquire(rq2->lock); /* Fake it out ;) */
2844 double_rq_clock_clear_update(rq1, rq2);
2845 }
2846
2847 /*
2848 * double_rq_unlock - safely unlock two runqueues
2849 *
2850 * Note this does not restore interrupts like task_rq_unlock,
2851 * you need to do so manually after calling.
2852 */
double_rq_unlock(struct rq * rq1,struct rq * rq2)2853 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2854 __releases(rq1->lock)
2855 __releases(rq2->lock)
2856 {
2857 WARN_ON_ONCE(rq1 != rq2);
2858 raw_spin_rq_unlock(rq1);
2859 __release(rq2->lock);
2860 }
2861
2862 #endif
2863
2864 DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq,
2865 double_rq_lock(_T->lock, _T->lock2),
2866 double_rq_unlock(_T->lock, _T->lock2))
2867
2868 extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq);
2869 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
2870 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
2871
2872 #ifdef CONFIG_SCHED_DEBUG
2873 extern bool sched_debug_verbose;
2874
2875 extern void print_cfs_stats(struct seq_file *m, int cpu);
2876 extern void print_rt_stats(struct seq_file *m, int cpu);
2877 extern void print_dl_stats(struct seq_file *m, int cpu);
2878 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
2879 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
2880 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
2881
2882 extern void resched_latency_warn(int cpu, u64 latency);
2883 #ifdef CONFIG_NUMA_BALANCING
2884 extern void
2885 show_numa_stats(struct task_struct *p, struct seq_file *m);
2886 extern void
2887 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
2888 unsigned long tpf, unsigned long gsf, unsigned long gpf);
2889 #endif /* CONFIG_NUMA_BALANCING */
2890 #else
resched_latency_warn(int cpu,u64 latency)2891 static inline void resched_latency_warn(int cpu, u64 latency) {}
2892 #endif /* CONFIG_SCHED_DEBUG */
2893
2894 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
2895 extern void init_rt_rq(struct rt_rq *rt_rq);
2896 extern void init_dl_rq(struct dl_rq *dl_rq);
2897
2898 extern void cfs_bandwidth_usage_inc(void);
2899 extern void cfs_bandwidth_usage_dec(void);
2900
2901 #ifdef CONFIG_NO_HZ_COMMON
2902 #define NOHZ_BALANCE_KICK_BIT 0
2903 #define NOHZ_STATS_KICK_BIT 1
2904 #define NOHZ_NEWILB_KICK_BIT 2
2905 #define NOHZ_NEXT_KICK_BIT 3
2906
2907 /* Run rebalance_domains() */
2908 #define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT)
2909 /* Update blocked load */
2910 #define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT)
2911 /* Update blocked load when entering idle */
2912 #define NOHZ_NEWILB_KICK BIT(NOHZ_NEWILB_KICK_BIT)
2913 /* Update nohz.next_balance */
2914 #define NOHZ_NEXT_KICK BIT(NOHZ_NEXT_KICK_BIT)
2915
2916 #define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK)
2917
2918 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
2919
2920 extern void nohz_balance_exit_idle(struct rq *rq);
2921 #else
nohz_balance_exit_idle(struct rq * rq)2922 static inline void nohz_balance_exit_idle(struct rq *rq) { }
2923 #endif
2924
2925 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
2926 extern void nohz_run_idle_balance(int cpu);
2927 #else
nohz_run_idle_balance(int cpu)2928 static inline void nohz_run_idle_balance(int cpu) { }
2929 #endif
2930
2931 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2932 struct irqtime {
2933 u64 total;
2934 u64 tick_delta;
2935 u64 irq_start_time;
2936 struct u64_stats_sync sync;
2937 };
2938
2939 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
2940
2941 /*
2942 * Returns the irqtime minus the softirq time computed by ksoftirqd.
2943 * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime
2944 * and never move forward.
2945 */
irq_time_read(int cpu)2946 static inline u64 irq_time_read(int cpu)
2947 {
2948 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
2949 unsigned int seq;
2950 u64 total;
2951
2952 do {
2953 seq = __u64_stats_fetch_begin(&irqtime->sync);
2954 total = irqtime->total;
2955 } while (__u64_stats_fetch_retry(&irqtime->sync, seq));
2956
2957 return total;
2958 }
2959 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
2960
2961 #ifdef CONFIG_CPU_FREQ
2962 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
2963
2964 /**
2965 * cpufreq_update_util - Take a note about CPU utilization changes.
2966 * @rq: Runqueue to carry out the update for.
2967 * @flags: Update reason flags.
2968 *
2969 * This function is called by the scheduler on the CPU whose utilization is
2970 * being updated.
2971 *
2972 * It can only be called from RCU-sched read-side critical sections.
2973 *
2974 * The way cpufreq is currently arranged requires it to evaluate the CPU
2975 * performance state (frequency/voltage) on a regular basis to prevent it from
2976 * being stuck in a completely inadequate performance level for too long.
2977 * That is not guaranteed to happen if the updates are only triggered from CFS
2978 * and DL, though, because they may not be coming in if only RT tasks are
2979 * active all the time (or there are RT tasks only).
2980 *
2981 * As a workaround for that issue, this function is called periodically by the
2982 * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
2983 * but that really is a band-aid. Going forward it should be replaced with
2984 * solutions targeted more specifically at RT tasks.
2985 */
cpufreq_update_util(struct rq * rq,unsigned int flags)2986 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
2987 {
2988 struct update_util_data *data;
2989
2990 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
2991 cpu_of(rq)));
2992 if (data)
2993 data->func(data, rq_clock(rq), flags);
2994 }
2995 #else
cpufreq_update_util(struct rq * rq,unsigned int flags)2996 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
2997 #endif /* CONFIG_CPU_FREQ */
2998
2999 #ifdef arch_scale_freq_capacity
3000 # ifndef arch_scale_freq_invariant
3001 # define arch_scale_freq_invariant() true
3002 # endif
3003 #else
3004 # define arch_scale_freq_invariant() false
3005 #endif
3006
3007 #ifdef CONFIG_SMP
3008 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
3009 unsigned long *min,
3010 unsigned long *max);
3011
3012 unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual,
3013 unsigned long min,
3014 unsigned long max);
3015
3016
3017 /*
3018 * Verify the fitness of task @p to run on @cpu taking into account the
3019 * CPU original capacity and the runtime/deadline ratio of the task.
3020 *
3021 * The function will return true if the original capacity of @cpu is
3022 * greater than or equal to task's deadline density right shifted by
3023 * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise.
3024 */
dl_task_fits_capacity(struct task_struct * p,int cpu)3025 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
3026 {
3027 unsigned long cap = arch_scale_cpu_capacity(cpu);
3028
3029 return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT);
3030 }
3031
cpu_bw_dl(struct rq * rq)3032 static inline unsigned long cpu_bw_dl(struct rq *rq)
3033 {
3034 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
3035 }
3036
cpu_util_dl(struct rq * rq)3037 static inline unsigned long cpu_util_dl(struct rq *rq)
3038 {
3039 return READ_ONCE(rq->avg_dl.util_avg);
3040 }
3041
3042
3043 extern unsigned long cpu_util_cfs(int cpu);
3044 extern unsigned long cpu_util_cfs_boost(int cpu);
3045
cpu_util_rt(struct rq * rq)3046 static inline unsigned long cpu_util_rt(struct rq *rq)
3047 {
3048 return READ_ONCE(rq->avg_rt.util_avg);
3049 }
3050 #endif
3051
3052 #ifdef CONFIG_UCLAMP_TASK
3053 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
3054
uclamp_rq_get(struct rq * rq,enum uclamp_id clamp_id)3055 static inline unsigned long uclamp_rq_get(struct rq *rq,
3056 enum uclamp_id clamp_id)
3057 {
3058 return READ_ONCE(rq->uclamp[clamp_id].value);
3059 }
3060
uclamp_rq_set(struct rq * rq,enum uclamp_id clamp_id,unsigned int value)3061 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id,
3062 unsigned int value)
3063 {
3064 WRITE_ONCE(rq->uclamp[clamp_id].value, value);
3065 }
3066
uclamp_rq_is_idle(struct rq * rq)3067 static inline bool uclamp_rq_is_idle(struct rq *rq)
3068 {
3069 return rq->uclamp_flags & UCLAMP_FLAG_IDLE;
3070 }
3071
3072 /* Is the rq being capped/throttled by uclamp_max? */
uclamp_rq_is_capped(struct rq * rq)3073 static inline bool uclamp_rq_is_capped(struct rq *rq)
3074 {
3075 unsigned long rq_util;
3076 unsigned long max_util;
3077
3078 if (!static_branch_likely(&sched_uclamp_used))
3079 return false;
3080
3081 rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq);
3082 max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
3083
3084 return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util;
3085 }
3086
3087 /*
3088 * When uclamp is compiled in, the aggregation at rq level is 'turned off'
3089 * by default in the fast path and only gets turned on once userspace performs
3090 * an operation that requires it.
3091 *
3092 * Returns true if userspace opted-in to use uclamp and aggregation at rq level
3093 * hence is active.
3094 */
uclamp_is_used(void)3095 static inline bool uclamp_is_used(void)
3096 {
3097 return static_branch_likely(&sched_uclamp_used);
3098 }
3099 #else /* CONFIG_UCLAMP_TASK */
uclamp_eff_value(struct task_struct * p,enum uclamp_id clamp_id)3100 static inline unsigned long uclamp_eff_value(struct task_struct *p,
3101 enum uclamp_id clamp_id)
3102 {
3103 if (clamp_id == UCLAMP_MIN)
3104 return 0;
3105
3106 return SCHED_CAPACITY_SCALE;
3107 }
3108
uclamp_rq_is_capped(struct rq * rq)3109 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; }
3110
uclamp_is_used(void)3111 static inline bool uclamp_is_used(void)
3112 {
3113 return false;
3114 }
3115
uclamp_rq_get(struct rq * rq,enum uclamp_id clamp_id)3116 static inline unsigned long uclamp_rq_get(struct rq *rq,
3117 enum uclamp_id clamp_id)
3118 {
3119 if (clamp_id == UCLAMP_MIN)
3120 return 0;
3121
3122 return SCHED_CAPACITY_SCALE;
3123 }
3124
uclamp_rq_set(struct rq * rq,enum uclamp_id clamp_id,unsigned int value)3125 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id,
3126 unsigned int value)
3127 {
3128 }
3129
uclamp_rq_is_idle(struct rq * rq)3130 static inline bool uclamp_rq_is_idle(struct rq *rq)
3131 {
3132 return false;
3133 }
3134 #endif /* CONFIG_UCLAMP_TASK */
3135
3136 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
cpu_util_irq(struct rq * rq)3137 static inline unsigned long cpu_util_irq(struct rq *rq)
3138 {
3139 return rq->avg_irq.util_avg;
3140 }
3141
3142 static inline
scale_irq_capacity(unsigned long util,unsigned long irq,unsigned long max)3143 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3144 {
3145 util *= (max - irq);
3146 util /= max;
3147
3148 return util;
3149
3150 }
3151 #else
cpu_util_irq(struct rq * rq)3152 static inline unsigned long cpu_util_irq(struct rq *rq)
3153 {
3154 return 0;
3155 }
3156
3157 static inline
scale_irq_capacity(unsigned long util,unsigned long irq,unsigned long max)3158 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3159 {
3160 return util;
3161 }
3162 #endif
3163
3164 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
3165
3166 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
3167
3168 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
3169
sched_energy_enabled(void)3170 static inline bool sched_energy_enabled(void)
3171 {
3172 return static_branch_unlikely(&sched_energy_present);
3173 }
3174
3175 extern struct cpufreq_governor schedutil_gov;
3176
3177 #else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
3178
3179 #define perf_domain_span(pd) NULL
sched_energy_enabled(void)3180 static inline bool sched_energy_enabled(void) { return false; }
3181
3182 #endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
3183
3184 #ifdef CONFIG_MEMBARRIER
3185 /*
3186 * The scheduler provides memory barriers required by membarrier between:
3187 * - prior user-space memory accesses and store to rq->membarrier_state,
3188 * - store to rq->membarrier_state and following user-space memory accesses.
3189 * In the same way it provides those guarantees around store to rq->curr.
3190 */
membarrier_switch_mm(struct rq * rq,struct mm_struct * prev_mm,struct mm_struct * next_mm)3191 static inline void membarrier_switch_mm(struct rq *rq,
3192 struct mm_struct *prev_mm,
3193 struct mm_struct *next_mm)
3194 {
3195 int membarrier_state;
3196
3197 if (prev_mm == next_mm)
3198 return;
3199
3200 membarrier_state = atomic_read(&next_mm->membarrier_state);
3201 if (READ_ONCE(rq->membarrier_state) == membarrier_state)
3202 return;
3203
3204 WRITE_ONCE(rq->membarrier_state, membarrier_state);
3205 }
3206 #else
membarrier_switch_mm(struct rq * rq,struct mm_struct * prev_mm,struct mm_struct * next_mm)3207 static inline void membarrier_switch_mm(struct rq *rq,
3208 struct mm_struct *prev_mm,
3209 struct mm_struct *next_mm)
3210 {
3211 }
3212 #endif
3213
3214 #ifdef CONFIG_SMP
is_per_cpu_kthread(struct task_struct * p)3215 static inline bool is_per_cpu_kthread(struct task_struct *p)
3216 {
3217 if (!(p->flags & PF_KTHREAD))
3218 return false;
3219
3220 if (p->nr_cpus_allowed != 1)
3221 return false;
3222
3223 return true;
3224 }
3225 #endif
3226
3227 extern void swake_up_all_locked(struct swait_queue_head *q);
3228 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
3229
3230 extern int try_to_wake_up(struct task_struct *tsk, unsigned int state, int wake_flags);
3231
3232 #ifdef CONFIG_PREEMPT_DYNAMIC
3233 extern int preempt_dynamic_mode;
3234 extern int sched_dynamic_mode(const char *str);
3235 extern void sched_dynamic_update(int mode);
3236 #endif
3237
3238 #ifdef CONFIG_SCHED_MM_CID
3239
3240 #define SCHED_MM_CID_PERIOD_NS (100ULL * 1000000) /* 100ms */
3241 #define MM_CID_SCAN_DELAY 100 /* 100ms */
3242
3243 extern raw_spinlock_t cid_lock;
3244 extern int use_cid_lock;
3245
3246 extern void sched_mm_cid_migrate_from(struct task_struct *t);
3247 extern void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t);
3248 extern void task_tick_mm_cid(struct rq *rq, struct task_struct *curr);
3249 extern void init_sched_mm_cid(struct task_struct *t);
3250
__mm_cid_put(struct mm_struct * mm,int cid)3251 static inline void __mm_cid_put(struct mm_struct *mm, int cid)
3252 {
3253 if (cid < 0)
3254 return;
3255 cpumask_clear_cpu(cid, mm_cidmask(mm));
3256 }
3257
3258 /*
3259 * The per-mm/cpu cid can have the MM_CID_LAZY_PUT flag set or transition to
3260 * the MM_CID_UNSET state without holding the rq lock, but the rq lock needs to
3261 * be held to transition to other states.
3262 *
3263 * State transitions synchronized with cmpxchg or try_cmpxchg need to be
3264 * consistent across cpus, which prevents use of this_cpu_cmpxchg.
3265 */
mm_cid_put_lazy(struct task_struct * t)3266 static inline void mm_cid_put_lazy(struct task_struct *t)
3267 {
3268 struct mm_struct *mm = t->mm;
3269 struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3270 int cid;
3271
3272 lockdep_assert_irqs_disabled();
3273 cid = __this_cpu_read(pcpu_cid->cid);
3274 if (!mm_cid_is_lazy_put(cid) ||
3275 !try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET))
3276 return;
3277 __mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3278 }
3279
mm_cid_pcpu_unset(struct mm_struct * mm)3280 static inline int mm_cid_pcpu_unset(struct mm_struct *mm)
3281 {
3282 struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3283 int cid, res;
3284
3285 lockdep_assert_irqs_disabled();
3286 cid = __this_cpu_read(pcpu_cid->cid);
3287 for (;;) {
3288 if (mm_cid_is_unset(cid))
3289 return MM_CID_UNSET;
3290 /*
3291 * Attempt transition from valid or lazy-put to unset.
3292 */
3293 res = cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, cid, MM_CID_UNSET);
3294 if (res == cid)
3295 break;
3296 cid = res;
3297 }
3298 return cid;
3299 }
3300
mm_cid_put(struct mm_struct * mm)3301 static inline void mm_cid_put(struct mm_struct *mm)
3302 {
3303 int cid;
3304
3305 lockdep_assert_irqs_disabled();
3306 cid = mm_cid_pcpu_unset(mm);
3307 if (cid == MM_CID_UNSET)
3308 return;
3309 __mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3310 }
3311
__mm_cid_try_get(struct mm_struct * mm)3312 static inline int __mm_cid_try_get(struct mm_struct *mm)
3313 {
3314 struct cpumask *cpumask;
3315 int cid;
3316
3317 cpumask = mm_cidmask(mm);
3318 /*
3319 * Retry finding first zero bit if the mask is temporarily
3320 * filled. This only happens during concurrent remote-clear
3321 * which owns a cid without holding a rq lock.
3322 */
3323 for (;;) {
3324 cid = cpumask_first_zero(cpumask);
3325 if (cid < nr_cpu_ids)
3326 break;
3327 cpu_relax();
3328 }
3329 if (cpumask_test_and_set_cpu(cid, cpumask))
3330 return -1;
3331 return cid;
3332 }
3333
3334 /*
3335 * Save a snapshot of the current runqueue time of this cpu
3336 * with the per-cpu cid value, allowing to estimate how recently it was used.
3337 */
mm_cid_snapshot_time(struct rq * rq,struct mm_struct * mm)3338 static inline void mm_cid_snapshot_time(struct rq *rq, struct mm_struct *mm)
3339 {
3340 struct mm_cid *pcpu_cid = per_cpu_ptr(mm->pcpu_cid, cpu_of(rq));
3341
3342 lockdep_assert_rq_held(rq);
3343 WRITE_ONCE(pcpu_cid->time, rq->clock);
3344 }
3345
__mm_cid_get(struct rq * rq,struct mm_struct * mm)3346 static inline int __mm_cid_get(struct rq *rq, struct mm_struct *mm)
3347 {
3348 int cid;
3349
3350 /*
3351 * All allocations (even those using the cid_lock) are lock-free. If
3352 * use_cid_lock is set, hold the cid_lock to perform cid allocation to
3353 * guarantee forward progress.
3354 */
3355 if (!READ_ONCE(use_cid_lock)) {
3356 cid = __mm_cid_try_get(mm);
3357 if (cid >= 0)
3358 goto end;
3359 raw_spin_lock(&cid_lock);
3360 } else {
3361 raw_spin_lock(&cid_lock);
3362 cid = __mm_cid_try_get(mm);
3363 if (cid >= 0)
3364 goto unlock;
3365 }
3366
3367 /*
3368 * cid concurrently allocated. Retry while forcing following
3369 * allocations to use the cid_lock to ensure forward progress.
3370 */
3371 WRITE_ONCE(use_cid_lock, 1);
3372 /*
3373 * Set use_cid_lock before allocation. Only care about program order
3374 * because this is only required for forward progress.
3375 */
3376 barrier();
3377 /*
3378 * Retry until it succeeds. It is guaranteed to eventually succeed once
3379 * all newcoming allocations observe the use_cid_lock flag set.
3380 */
3381 do {
3382 cid = __mm_cid_try_get(mm);
3383 cpu_relax();
3384 } while (cid < 0);
3385 /*
3386 * Allocate before clearing use_cid_lock. Only care about
3387 * program order because this is for forward progress.
3388 */
3389 barrier();
3390 WRITE_ONCE(use_cid_lock, 0);
3391 unlock:
3392 raw_spin_unlock(&cid_lock);
3393 end:
3394 mm_cid_snapshot_time(rq, mm);
3395 return cid;
3396 }
3397
mm_cid_get(struct rq * rq,struct mm_struct * mm)3398 static inline int mm_cid_get(struct rq *rq, struct mm_struct *mm)
3399 {
3400 struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid;
3401 struct cpumask *cpumask;
3402 int cid;
3403
3404 lockdep_assert_rq_held(rq);
3405 cpumask = mm_cidmask(mm);
3406 cid = __this_cpu_read(pcpu_cid->cid);
3407 if (mm_cid_is_valid(cid)) {
3408 mm_cid_snapshot_time(rq, mm);
3409 return cid;
3410 }
3411 if (mm_cid_is_lazy_put(cid)) {
3412 if (try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET))
3413 __mm_cid_put(mm, mm_cid_clear_lazy_put(cid));
3414 }
3415 cid = __mm_cid_get(rq, mm);
3416 __this_cpu_write(pcpu_cid->cid, cid);
3417 return cid;
3418 }
3419
switch_mm_cid(struct rq * rq,struct task_struct * prev,struct task_struct * next)3420 static inline void switch_mm_cid(struct rq *rq,
3421 struct task_struct *prev,
3422 struct task_struct *next)
3423 {
3424 /*
3425 * Provide a memory barrier between rq->curr store and load of
3426 * {prev,next}->mm->pcpu_cid[cpu] on rq->curr->mm transition.
3427 *
3428 * Should be adapted if context_switch() is modified.
3429 */
3430 if (!next->mm) { // to kernel
3431 /*
3432 * user -> kernel transition does not guarantee a barrier, but
3433 * we can use the fact that it performs an atomic operation in
3434 * mmgrab().
3435 */
3436 if (prev->mm) // from user
3437 smp_mb__after_mmgrab();
3438 /*
3439 * kernel -> kernel transition does not change rq->curr->mm
3440 * state. It stays NULL.
3441 */
3442 } else { // to user
3443 /*
3444 * kernel -> user transition does not provide a barrier
3445 * between rq->curr store and load of {prev,next}->mm->pcpu_cid[cpu].
3446 * Provide it here.
3447 */
3448 if (!prev->mm) // from kernel
3449 smp_mb();
3450 /*
3451 * user -> user transition guarantees a memory barrier through
3452 * switch_mm() when current->mm changes. If current->mm is
3453 * unchanged, no barrier is needed.
3454 */
3455 }
3456 if (prev->mm_cid_active) {
3457 mm_cid_snapshot_time(rq, prev->mm);
3458 mm_cid_put_lazy(prev);
3459 prev->mm_cid = -1;
3460 }
3461 if (next->mm_cid_active)
3462 next->last_mm_cid = next->mm_cid = mm_cid_get(rq, next->mm);
3463 }
3464
3465 #else
switch_mm_cid(struct rq * rq,struct task_struct * prev,struct task_struct * next)3466 static inline void switch_mm_cid(struct rq *rq, struct task_struct *prev, struct task_struct *next) { }
sched_mm_cid_migrate_from(struct task_struct * t)3467 static inline void sched_mm_cid_migrate_from(struct task_struct *t) { }
sched_mm_cid_migrate_to(struct rq * dst_rq,struct task_struct * t)3468 static inline void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t) { }
task_tick_mm_cid(struct rq * rq,struct task_struct * curr)3469 static inline void task_tick_mm_cid(struct rq *rq, struct task_struct *curr) { }
init_sched_mm_cid(struct task_struct * t)3470 static inline void init_sched_mm_cid(struct task_struct *t) { }
3471 #endif
3472
3473 extern u64 avg_vruntime(struct cfs_rq *cfs_rq);
3474 extern int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se);
3475
3476 #endif /* _KERNEL_SCHED_SCHED_H */
3477