1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Scheduler internal types and methods:
4 */
5 #ifndef _KERNEL_SCHED_SCHED_H
6 #define _KERNEL_SCHED_SCHED_H
7
8 #include <linux/prandom.h>
9 #include <linux/sched/affinity.h>
10 #include <linux/sched/autogroup.h>
11 #include <linux/sched/cpufreq.h>
12 #include <linux/sched/deadline.h>
13 #include <linux/sched.h>
14 #include <linux/sched/loadavg.h>
15 #include <linux/sched/mm.h>
16 #include <linux/sched/rseq_api.h>
17 #include <linux/sched/signal.h>
18 #include <linux/sched/smt.h>
19 #include <linux/sched/stat.h>
20 #include <linux/sched/sysctl.h>
21 #include <linux/sched/task_flags.h>
22 #include <linux/sched/task.h>
23 #include <linux/sched/topology.h>
24 #include <linux/atomic.h>
25 #include <linux/bitmap.h>
26 #include <linux/bug.h>
27 #include <linux/capability.h>
28 #include <linux/cgroup_api.h>
29 #include <linux/cgroup.h>
30 #include <linux/context_tracking.h>
31 #include <linux/cpufreq.h>
32 #include <linux/cpumask_api.h>
33 #include <linux/ctype.h>
34 #include <linux/file.h>
35 #include <linux/fs_api.h>
36 #include <linux/hrtimer_api.h>
37 #include <linux/interrupt.h>
38 #include <linux/irq_work.h>
39 #include <linux/jiffies.h>
40 #include <linux/kref_api.h>
41 #include <linux/kthread.h>
42 #include <linux/ktime_api.h>
43 #include <linux/lockdep_api.h>
44 #include <linux/lockdep.h>
45 #include <linux/minmax.h>
46 #include <linux/mm.h>
47 #include <linux/module.h>
48 #include <linux/mutex_api.h>
49 #include <linux/plist.h>
50 #include <linux/poll.h>
51 #include <linux/proc_fs.h>
52 #include <linux/profile.h>
53 #include <linux/psi.h>
54 #include <linux/rcupdate.h>
55 #include <linux/seq_file.h>
56 #include <linux/seqlock.h>
57 #include <linux/softirq.h>
58 #include <linux/spinlock_api.h>
59 #include <linux/static_key.h>
60 #include <linux/stop_machine.h>
61 #include <linux/syscalls_api.h>
62 #include <linux/syscalls.h>
63 #include <linux/tick.h>
64 #include <linux/topology.h>
65 #include <linux/types.h>
66 #include <linux/u64_stats_sync_api.h>
67 #include <linux/uaccess.h>
68 #include <linux/wait_api.h>
69 #include <linux/wait_bit.h>
70 #include <linux/workqueue_api.h>
71 #include <linux/delayacct.h>
72 #include <linux/mmu_context.h>
73
74 #include <trace/events/power.h>
75 #include <trace/events/sched.h>
76
77 #include "../workqueue_internal.h"
78
79 struct rq;
80 struct cfs_rq;
81 struct rt_rq;
82 struct sched_group;
83 struct cpuidle_state;
84
85 #ifdef CONFIG_PARAVIRT
86 # include <asm/paravirt.h>
87 # include <asm/paravirt_api_clock.h>
88 #endif
89
90 #include <asm/barrier.h>
91
92 #include "cpupri.h"
93 #include "cpudeadline.h"
94
95 /* task_struct::on_rq states: */
96 #define TASK_ON_RQ_QUEUED 1
97 #define TASK_ON_RQ_MIGRATING 2
98
99 extern __read_mostly int scheduler_running;
100
101 extern unsigned long calc_load_update;
102 extern atomic_long_t calc_load_tasks;
103
104 extern void calc_global_load_tick(struct rq *this_rq);
105 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
106
107 extern void call_trace_sched_update_nr_running(struct rq *rq, int count);
108
109 extern int sysctl_sched_rt_period;
110 extern int sysctl_sched_rt_runtime;
111 extern int sched_rr_timeslice;
112
113 /*
114 * Asymmetric CPU capacity bits
115 */
116 struct asym_cap_data {
117 struct list_head link;
118 struct rcu_head rcu;
119 unsigned long capacity;
120 unsigned long cpus[];
121 };
122
123 extern struct list_head asym_cap_list;
124
125 #define cpu_capacity_span(asym_data) to_cpumask((asym_data)->cpus)
126
127 /*
128 * Helpers for converting nanosecond timing to jiffy resolution
129 */
130 #define NS_TO_JIFFIES(time) ((unsigned long)(time) / (NSEC_PER_SEC/HZ))
131
132 /*
133 * Increase resolution of nice-level calculations for 64-bit architectures.
134 * The extra resolution improves shares distribution and load balancing of
135 * low-weight task groups (eg. nice +19 on an autogroup), deeper task-group
136 * hierarchies, especially on larger systems. This is not a user-visible change
137 * and does not change the user-interface for setting shares/weights.
138 *
139 * We increase resolution only if we have enough bits to allow this increased
140 * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
141 * are pretty high and the returns do not justify the increased costs.
142 *
143 * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
144 * increase coverage and consistency always enable it on 64-bit platforms.
145 */
146 #ifdef CONFIG_64BIT
147 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
148 # define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT)
149 # define scale_load_down(w) \
150 ({ \
151 unsigned long __w = (w); \
152 \
153 if (__w) \
154 __w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \
155 __w; \
156 })
157 #else
158 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT)
159 # define scale_load(w) (w)
160 # define scale_load_down(w) (w)
161 #endif
162
163 /*
164 * Task weight (visible to users) and its load (invisible to users) have
165 * independent resolution, but they should be well calibrated. We use
166 * scale_load() and scale_load_down(w) to convert between them. The
167 * following must be true:
168 *
169 * scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD
170 *
171 */
172 #define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT)
173
174 /*
175 * Single value that decides SCHED_DEADLINE internal math precision.
176 * 10 -> just above 1us
177 * 9 -> just above 0.5us
178 */
179 #define DL_SCALE 10
180
181 /*
182 * Single value that denotes runtime == period, ie unlimited time.
183 */
184 #define RUNTIME_INF ((u64)~0ULL)
185
idle_policy(int policy)186 static inline int idle_policy(int policy)
187 {
188 return policy == SCHED_IDLE;
189 }
190
normal_policy(int policy)191 static inline int normal_policy(int policy)
192 {
193 #ifdef CONFIG_SCHED_CLASS_EXT
194 if (policy == SCHED_EXT)
195 return true;
196 #endif
197 return policy == SCHED_NORMAL;
198 }
199
fair_policy(int policy)200 static inline int fair_policy(int policy)
201 {
202 return normal_policy(policy) || policy == SCHED_BATCH;
203 }
204
rt_policy(int policy)205 static inline int rt_policy(int policy)
206 {
207 return policy == SCHED_FIFO || policy == SCHED_RR;
208 }
209
dl_policy(int policy)210 static inline int dl_policy(int policy)
211 {
212 return policy == SCHED_DEADLINE;
213 }
214
valid_policy(int policy)215 static inline bool valid_policy(int policy)
216 {
217 return idle_policy(policy) || fair_policy(policy) ||
218 rt_policy(policy) || dl_policy(policy);
219 }
220
task_has_idle_policy(struct task_struct * p)221 static inline int task_has_idle_policy(struct task_struct *p)
222 {
223 return idle_policy(p->policy);
224 }
225
task_has_rt_policy(struct task_struct * p)226 static inline int task_has_rt_policy(struct task_struct *p)
227 {
228 return rt_policy(p->policy);
229 }
230
task_has_dl_policy(struct task_struct * p)231 static inline int task_has_dl_policy(struct task_struct *p)
232 {
233 return dl_policy(p->policy);
234 }
235
236 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
237
update_avg(u64 * avg,u64 sample)238 static inline void update_avg(u64 *avg, u64 sample)
239 {
240 s64 diff = sample - *avg;
241
242 *avg += diff / 8;
243 }
244
245 /*
246 * Shifting a value by an exponent greater *or equal* to the size of said value
247 * is UB; cap at size-1.
248 */
249 #define shr_bound(val, shift) \
250 (val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1))
251
252 /*
253 * cgroup weight knobs should use the common MIN, DFL and MAX values which are
254 * 1, 100 and 10000 respectively. While it loses a bit of range on both ends, it
255 * maps pretty well onto the shares value used by scheduler and the round-trip
256 * conversions preserve the original value over the entire range.
257 */
sched_weight_from_cgroup(unsigned long cgrp_weight)258 static inline unsigned long sched_weight_from_cgroup(unsigned long cgrp_weight)
259 {
260 return DIV_ROUND_CLOSEST_ULL(cgrp_weight * 1024, CGROUP_WEIGHT_DFL);
261 }
262
sched_weight_to_cgroup(unsigned long weight)263 static inline unsigned long sched_weight_to_cgroup(unsigned long weight)
264 {
265 return clamp_t(unsigned long,
266 DIV_ROUND_CLOSEST_ULL(weight * CGROUP_WEIGHT_DFL, 1024),
267 CGROUP_WEIGHT_MIN, CGROUP_WEIGHT_MAX);
268 }
269
270 /*
271 * !! For sched_setattr_nocheck() (kernel) only !!
272 *
273 * This is actually gross. :(
274 *
275 * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
276 * tasks, but still be able to sleep. We need this on platforms that cannot
277 * atomically change clock frequency. Remove once fast switching will be
278 * available on such platforms.
279 *
280 * SUGOV stands for SchedUtil GOVernor.
281 */
282 #define SCHED_FLAG_SUGOV 0x10000000
283
284 #define SCHED_DL_FLAGS (SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV)
285
dl_entity_is_special(const struct sched_dl_entity * dl_se)286 static inline bool dl_entity_is_special(const struct sched_dl_entity *dl_se)
287 {
288 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
289 return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
290 #else
291 return false;
292 #endif
293 }
294
295 /*
296 * Tells if entity @a should preempt entity @b.
297 */
dl_entity_preempt(const struct sched_dl_entity * a,const struct sched_dl_entity * b)298 static inline bool dl_entity_preempt(const struct sched_dl_entity *a,
299 const struct sched_dl_entity *b)
300 {
301 return dl_entity_is_special(a) ||
302 dl_time_before(a->deadline, b->deadline);
303 }
304
305 /*
306 * This is the priority-queue data structure of the RT scheduling class:
307 */
308 struct rt_prio_array {
309 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
310 struct list_head queue[MAX_RT_PRIO];
311 };
312
313 struct rt_bandwidth {
314 /* nests inside the rq lock: */
315 raw_spinlock_t rt_runtime_lock;
316 ktime_t rt_period;
317 u64 rt_runtime;
318 struct hrtimer rt_period_timer;
319 unsigned int rt_period_active;
320 };
321
dl_bandwidth_enabled(void)322 static inline int dl_bandwidth_enabled(void)
323 {
324 return sysctl_sched_rt_runtime >= 0;
325 }
326
327 /*
328 * To keep the bandwidth of -deadline tasks under control
329 * we need some place where:
330 * - store the maximum -deadline bandwidth of each cpu;
331 * - cache the fraction of bandwidth that is currently allocated in
332 * each root domain;
333 *
334 * This is all done in the data structure below. It is similar to the
335 * one used for RT-throttling (rt_bandwidth), with the main difference
336 * that, since here we are only interested in admission control, we
337 * do not decrease any runtime while the group "executes", neither we
338 * need a timer to replenish it.
339 *
340 * With respect to SMP, bandwidth is given on a per root domain basis,
341 * meaning that:
342 * - bw (< 100%) is the deadline bandwidth of each CPU;
343 * - total_bw is the currently allocated bandwidth in each root domain;
344 */
345 struct dl_bw {
346 raw_spinlock_t lock;
347 u64 bw;
348 u64 total_bw;
349 };
350
351 extern void init_dl_bw(struct dl_bw *dl_b);
352 extern int sched_dl_global_validate(void);
353 extern void sched_dl_do_global(void);
354 extern int sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
355 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
356 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
357 extern bool __checkparam_dl(const struct sched_attr *attr);
358 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
359 extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
360 extern int dl_bw_deactivate(int cpu);
361 extern s64 dl_scaled_delta_exec(struct rq *rq, struct sched_dl_entity *dl_se, s64 delta_exec);
362 /*
363 * SCHED_DEADLINE supports servers (nested scheduling) with the following
364 * interface:
365 *
366 * dl_se::rq -- runqueue we belong to.
367 *
368 * dl_se::server_pick() -- nested pick_next_task(); we yield the period if this
369 * returns NULL.
370 *
371 * dl_server_update() -- called from update_curr_common(), propagates runtime
372 * to the server.
373 *
374 * dl_server_start() -- start the server when it has tasks; it will stop
375 * automatically when there are no more tasks, per
376 * dl_se::server_pick() returning NULL.
377 *
378 * dl_server_stop() -- (force) stop the server; use when updating
379 * parameters.
380 *
381 * dl_server_init() -- initializes the server.
382 *
383 * When started the dl_server will (per dl_defer) schedule a timer for its
384 * zero-laxity point -- that is, unlike regular EDF tasks which run ASAP, a
385 * server will run at the very end of its period.
386 *
387 * This is done such that any runtime from the target class can be accounted
388 * against the server -- through dl_server_update() above -- such that when it
389 * becomes time to run, it might already be out of runtime and get deferred
390 * until the next period. In this case dl_server_timer() will alternate
391 * between defer and replenish but never actually enqueue the server.
392 *
393 * Only when the target class does not manage to exhaust the server's runtime
394 * (there's actualy starvation in the given period), will the dl_server get on
395 * the runqueue. Once queued it will pick tasks from the target class and run
396 * them until either its runtime is exhaused, at which point its back to
397 * dl_server_timer, or until there are no more tasks to run, at which point
398 * the dl_server stops itself.
399 *
400 * By stopping at this point the dl_server retains bandwidth, which, if a new
401 * task wakes up imminently (starting the server again), can be used --
402 * subject to CBS wakeup rules -- without having to wait for the next period.
403 *
404 * Additionally, because of the dl_defer behaviour the start/stop behaviour is
405 * naturally thottled to once per period, avoiding high context switch
406 * workloads from spamming the hrtimer program/cancel paths.
407 */
408 extern void dl_server_update_idle(struct sched_dl_entity *dl_se, s64 delta_exec);
409 extern void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec);
410 extern void dl_server_start(struct sched_dl_entity *dl_se);
411 extern void dl_server_stop(struct sched_dl_entity *dl_se);
412 extern void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq,
413 dl_server_pick_f pick_task);
414 extern void sched_init_dl_servers(void);
415
416 extern void fair_server_init(struct rq *rq);
417 extern void __dl_server_attach_root(struct sched_dl_entity *dl_se, struct rq *rq);
418 extern int dl_server_apply_params(struct sched_dl_entity *dl_se,
419 u64 runtime, u64 period, bool init);
420
dl_server_active(struct sched_dl_entity * dl_se)421 static inline bool dl_server_active(struct sched_dl_entity *dl_se)
422 {
423 return dl_se->dl_server_active;
424 }
425
426 #ifdef CONFIG_CGROUP_SCHED
427
428 extern struct list_head task_groups;
429
430 #ifdef CONFIG_GROUP_SCHED_BANDWIDTH
431 extern const u64 max_bw_quota_period_us;
432
433 /*
434 * default period for group bandwidth.
435 * default: 0.1s, units: microseconds
436 */
default_bw_period_us(void)437 static inline u64 default_bw_period_us(void)
438 {
439 return 100000ULL;
440 }
441 #endif /* CONFIG_GROUP_SCHED_BANDWIDTH */
442
443 struct cfs_bandwidth {
444 #ifdef CONFIG_CFS_BANDWIDTH
445 raw_spinlock_t lock;
446 ktime_t period;
447 u64 quota;
448 u64 runtime;
449 u64 burst;
450 u64 runtime_snap;
451 s64 hierarchical_quota;
452
453 u8 idle;
454 u8 period_active;
455 u8 slack_started;
456 struct hrtimer period_timer;
457 struct hrtimer slack_timer;
458 struct list_head throttled_cfs_rq;
459
460 /* Statistics: */
461 int nr_periods;
462 int nr_throttled;
463 int nr_burst;
464 u64 throttled_time;
465 u64 burst_time;
466 #endif /* CONFIG_CFS_BANDWIDTH */
467 };
468
469 /* Task group related information */
470 struct task_group {
471 struct cgroup_subsys_state css;
472
473 #ifdef CONFIG_GROUP_SCHED_WEIGHT
474 /* A positive value indicates that this is a SCHED_IDLE group. */
475 int idle;
476 #endif
477
478 #ifdef CONFIG_FAIR_GROUP_SCHED
479 /* schedulable entities of this group on each CPU */
480 struct sched_entity **se;
481 /* runqueue "owned" by this group on each CPU */
482 struct cfs_rq **cfs_rq;
483 unsigned long shares;
484 /*
485 * load_avg can be heavily contended at clock tick time, so put
486 * it in its own cache-line separated from the fields above which
487 * will also be accessed at each tick.
488 */
489 atomic_long_t load_avg ____cacheline_aligned;
490 #endif /* CONFIG_FAIR_GROUP_SCHED */
491
492 #ifdef CONFIG_RT_GROUP_SCHED
493 struct sched_rt_entity **rt_se;
494 struct rt_rq **rt_rq;
495
496 struct rt_bandwidth rt_bandwidth;
497 #endif
498
499 struct scx_task_group scx;
500
501 struct rcu_head rcu;
502 struct list_head list;
503
504 struct task_group *parent;
505 struct list_head siblings;
506 struct list_head children;
507
508 #ifdef CONFIG_SCHED_AUTOGROUP
509 struct autogroup *autogroup;
510 #endif
511
512 struct cfs_bandwidth cfs_bandwidth;
513
514 #ifdef CONFIG_UCLAMP_TASK_GROUP
515 /* The two decimal precision [%] value requested from user-space */
516 unsigned int uclamp_pct[UCLAMP_CNT];
517 /* Clamp values requested for a task group */
518 struct uclamp_se uclamp_req[UCLAMP_CNT];
519 /* Effective clamp values used for a task group */
520 struct uclamp_se uclamp[UCLAMP_CNT];
521 #endif
522
523 };
524
525 #ifdef CONFIG_GROUP_SCHED_WEIGHT
526 #define ROOT_TASK_GROUP_LOAD NICE_0_LOAD
527
528 /*
529 * A weight of 0 or 1 can cause arithmetics problems.
530 * A weight of a cfs_rq is the sum of weights of which entities
531 * are queued on this cfs_rq, so a weight of a entity should not be
532 * too large, so as the shares value of a task group.
533 * (The default weight is 1024 - so there's no practical
534 * limitation from this.)
535 */
536 #define MIN_SHARES (1UL << 1)
537 #define MAX_SHARES (1UL << 18)
538 #endif
539
540 typedef int (*tg_visitor)(struct task_group *, void *);
541
542 extern int walk_tg_tree_from(struct task_group *from,
543 tg_visitor down, tg_visitor up, void *data);
544
545 /*
546 * Iterate the full tree, calling @down when first entering a node and @up when
547 * leaving it for the final time.
548 *
549 * Caller must hold rcu_lock or sufficient equivalent.
550 */
walk_tg_tree(tg_visitor down,tg_visitor up,void * data)551 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
552 {
553 return walk_tg_tree_from(&root_task_group, down, up, data);
554 }
555
css_tg(struct cgroup_subsys_state * css)556 static inline struct task_group *css_tg(struct cgroup_subsys_state *css)
557 {
558 return css ? container_of(css, struct task_group, css) : NULL;
559 }
560
561 extern int tg_nop(struct task_group *tg, void *data);
562
563 #ifdef CONFIG_FAIR_GROUP_SCHED
564 extern void free_fair_sched_group(struct task_group *tg);
565 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
566 extern void online_fair_sched_group(struct task_group *tg);
567 extern void unregister_fair_sched_group(struct task_group *tg);
568 #else /* !CONFIG_FAIR_GROUP_SCHED: */
free_fair_sched_group(struct task_group * tg)569 static inline void free_fair_sched_group(struct task_group *tg) { }
alloc_fair_sched_group(struct task_group * tg,struct task_group * parent)570 static inline int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
571 {
572 return 1;
573 }
online_fair_sched_group(struct task_group * tg)574 static inline void online_fair_sched_group(struct task_group *tg) { }
unregister_fair_sched_group(struct task_group * tg)575 static inline void unregister_fair_sched_group(struct task_group *tg) { }
576 #endif /* !CONFIG_FAIR_GROUP_SCHED */
577
578 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
579 struct sched_entity *se, int cpu,
580 struct sched_entity *parent);
581 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b, struct cfs_bandwidth *parent);
582
583 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
584 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
585 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
586 extern bool cfs_task_bw_constrained(struct task_struct *p);
587
588 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
589 struct sched_rt_entity *rt_se, int cpu,
590 struct sched_rt_entity *parent);
591 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
592 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
593 extern long sched_group_rt_runtime(struct task_group *tg);
594 extern long sched_group_rt_period(struct task_group *tg);
595 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
596
597 extern struct task_group *sched_create_group(struct task_group *parent);
598 extern void sched_online_group(struct task_group *tg,
599 struct task_group *parent);
600 extern void sched_destroy_group(struct task_group *tg);
601 extern void sched_release_group(struct task_group *tg);
602
603 extern void sched_move_task(struct task_struct *tsk, bool for_autogroup);
604
605 #ifdef CONFIG_FAIR_GROUP_SCHED
606 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
607
608 extern int sched_group_set_idle(struct task_group *tg, long idle);
609
610 extern void set_task_rq_fair(struct sched_entity *se,
611 struct cfs_rq *prev, struct cfs_rq *next);
612 #else /* !CONFIG_FAIR_GROUP_SCHED: */
sched_group_set_shares(struct task_group * tg,unsigned long shares)613 static inline int sched_group_set_shares(struct task_group *tg, unsigned long shares) { return 0; }
sched_group_set_idle(struct task_group * tg,long idle)614 static inline int sched_group_set_idle(struct task_group *tg, long idle) { return 0; }
615 #endif /* !CONFIG_FAIR_GROUP_SCHED */
616
617 #else /* !CONFIG_CGROUP_SCHED: */
618
619 struct cfs_bandwidth { };
620
cfs_task_bw_constrained(struct task_struct * p)621 static inline bool cfs_task_bw_constrained(struct task_struct *p) { return false; }
622
623 #endif /* !CONFIG_CGROUP_SCHED */
624
625 extern void unregister_rt_sched_group(struct task_group *tg);
626 extern void free_rt_sched_group(struct task_group *tg);
627 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
628
629 /*
630 * u64_u32_load/u64_u32_store
631 *
632 * Use a copy of a u64 value to protect against data race. This is only
633 * applicable for 32-bits architectures.
634 */
635 #ifdef CONFIG_64BIT
636 # define u64_u32_load_copy(var, copy) var
637 # define u64_u32_store_copy(var, copy, val) (var = val)
638 #else
639 # define u64_u32_load_copy(var, copy) \
640 ({ \
641 u64 __val, __val_copy; \
642 do { \
643 __val_copy = copy; \
644 /* \
645 * paired with u64_u32_store_copy(), ordering access \
646 * to var and copy. \
647 */ \
648 smp_rmb(); \
649 __val = var; \
650 } while (__val != __val_copy); \
651 __val; \
652 })
653 # define u64_u32_store_copy(var, copy, val) \
654 do { \
655 typeof(val) __val = (val); \
656 var = __val; \
657 /* \
658 * paired with u64_u32_load_copy(), ordering access to var and \
659 * copy. \
660 */ \
661 smp_wmb(); \
662 copy = __val; \
663 } while (0)
664 #endif
665 # define u64_u32_load(var) u64_u32_load_copy(var, var##_copy)
666 # define u64_u32_store(var, val) u64_u32_store_copy(var, var##_copy, val)
667
668 struct balance_callback {
669 struct balance_callback *next;
670 void (*func)(struct rq *rq);
671 };
672
673 /* CFS-related fields in a runqueue */
674 struct cfs_rq {
675 struct load_weight load;
676 unsigned int nr_queued;
677 unsigned int h_nr_queued; /* SCHED_{NORMAL,BATCH,IDLE} */
678 unsigned int h_nr_runnable; /* SCHED_{NORMAL,BATCH,IDLE} */
679 unsigned int h_nr_idle; /* SCHED_IDLE */
680
681 s64 avg_vruntime;
682 u64 avg_load;
683
684 u64 zero_vruntime;
685 #ifdef CONFIG_SCHED_CORE
686 unsigned int forceidle_seq;
687 u64 zero_vruntime_fi;
688 #endif
689
690 struct rb_root_cached tasks_timeline;
691
692 /*
693 * 'curr' points to currently running entity on this cfs_rq.
694 * It is set to NULL otherwise (i.e when none are currently running).
695 */
696 struct sched_entity *curr;
697 struct sched_entity *next;
698
699 /*
700 * CFS load tracking
701 */
702 struct sched_avg avg;
703 #ifndef CONFIG_64BIT
704 u64 last_update_time_copy;
705 #endif
706 struct {
707 raw_spinlock_t lock ____cacheline_aligned;
708 int nr;
709 unsigned long load_avg;
710 unsigned long util_avg;
711 unsigned long runnable_avg;
712 } removed;
713
714 #ifdef CONFIG_FAIR_GROUP_SCHED
715 u64 last_update_tg_load_avg;
716 unsigned long tg_load_avg_contrib;
717 long propagate;
718 long prop_runnable_sum;
719
720 /*
721 * h_load = weight * f(tg)
722 *
723 * Where f(tg) is the recursive weight fraction assigned to
724 * this group.
725 */
726 unsigned long h_load;
727 u64 last_h_load_update;
728 struct sched_entity *h_load_next;
729 #endif /* CONFIG_FAIR_GROUP_SCHED */
730
731 #ifdef CONFIG_FAIR_GROUP_SCHED
732 struct rq *rq; /* CPU runqueue to which this cfs_rq is attached */
733
734 /*
735 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
736 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
737 * (like users, containers etc.)
738 *
739 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
740 * This list is used during load balance.
741 */
742 int on_list;
743 struct list_head leaf_cfs_rq_list;
744 struct task_group *tg; /* group that "owns" this runqueue */
745
746 /* Locally cached copy of our task_group's idle value */
747 int idle;
748
749 #ifdef CONFIG_CFS_BANDWIDTH
750 int runtime_enabled;
751 s64 runtime_remaining;
752
753 u64 throttled_pelt_idle;
754 #ifndef CONFIG_64BIT
755 u64 throttled_pelt_idle_copy;
756 #endif
757 u64 throttled_clock;
758 u64 throttled_clock_pelt;
759 u64 throttled_clock_pelt_time;
760 u64 throttled_clock_self;
761 u64 throttled_clock_self_time;
762 bool throttled:1;
763 bool pelt_clock_throttled:1;
764 int throttle_count;
765 struct list_head throttled_list;
766 struct list_head throttled_csd_list;
767 struct list_head throttled_limbo_list;
768 #endif /* CONFIG_CFS_BANDWIDTH */
769 #endif /* CONFIG_FAIR_GROUP_SCHED */
770 };
771
772 #ifdef CONFIG_SCHED_CLASS_EXT
773 /* scx_rq->flags, protected by the rq lock */
774 enum scx_rq_flags {
775 /*
776 * A hotplugged CPU starts scheduling before rq_online_scx(). Track
777 * ops.cpu_on/offline() state so that ops.enqueue/dispatch() are called
778 * only while the BPF scheduler considers the CPU to be online.
779 */
780 SCX_RQ_ONLINE = 1 << 0,
781 SCX_RQ_CAN_STOP_TICK = 1 << 1,
782 SCX_RQ_BAL_KEEP = 1 << 3, /* balance decided to keep current */
783 SCX_RQ_BYPASSING = 1 << 4,
784 SCX_RQ_CLK_VALID = 1 << 5, /* RQ clock is fresh and valid */
785 SCX_RQ_BAL_CB_PENDING = 1 << 6, /* must queue a cb after dispatching */
786
787 SCX_RQ_IN_WAKEUP = 1 << 16,
788 SCX_RQ_IN_BALANCE = 1 << 17,
789 };
790
791 struct scx_rq {
792 struct scx_dispatch_q local_dsq;
793 struct list_head runnable_list; /* runnable tasks on this rq */
794 struct list_head ddsp_deferred_locals; /* deferred ddsps from enq */
795 unsigned long ops_qseq;
796 u64 extra_enq_flags; /* see move_task_to_local_dsq() */
797 u32 nr_running;
798 u32 cpuperf_target; /* [0, SCHED_CAPACITY_SCALE] */
799 bool cpu_released;
800 u32 flags;
801 u64 clock; /* current per-rq clock -- see scx_bpf_now() */
802 cpumask_var_t cpus_to_kick;
803 cpumask_var_t cpus_to_kick_if_idle;
804 cpumask_var_t cpus_to_preempt;
805 cpumask_var_t cpus_to_wait;
806 unsigned long kick_sync;
807 local_t reenq_local_deferred;
808 struct balance_callback deferred_bal_cb;
809 struct irq_work deferred_irq_work;
810 struct irq_work kick_cpus_irq_work;
811 struct scx_dispatch_q bypass_dsq;
812 };
813 #endif /* CONFIG_SCHED_CLASS_EXT */
814
rt_bandwidth_enabled(void)815 static inline int rt_bandwidth_enabled(void)
816 {
817 return sysctl_sched_rt_runtime >= 0;
818 }
819
820 /* RT IPI pull logic requires IRQ_WORK */
821 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
822 # define HAVE_RT_PUSH_IPI
823 #endif
824
825 /* Real-Time classes' related field in a runqueue: */
826 struct rt_rq {
827 struct rt_prio_array active;
828 unsigned int rt_nr_running;
829 unsigned int rr_nr_running;
830 struct {
831 int curr; /* highest queued rt task prio */
832 int next; /* next highest */
833 } highest_prio;
834 bool overloaded;
835 struct plist_head pushable_tasks;
836
837 int rt_queued;
838
839 #ifdef CONFIG_RT_GROUP_SCHED
840 int rt_throttled;
841 u64 rt_time; /* consumed RT time, goes up in update_curr_rt */
842 u64 rt_runtime; /* allotted RT time, "slice" from rt_bandwidth, RT sharing/balancing */
843 /* Nests inside the rq lock: */
844 raw_spinlock_t rt_runtime_lock;
845
846 unsigned int rt_nr_boosted;
847
848 struct rq *rq; /* this is always top-level rq, cache? */
849 #endif
850 #ifdef CONFIG_CGROUP_SCHED
851 struct task_group *tg; /* this tg has "this" rt_rq on given CPU for runnable entities */
852 #endif
853 };
854
rt_rq_is_runnable(struct rt_rq * rt_rq)855 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
856 {
857 return rt_rq->rt_queued && rt_rq->rt_nr_running;
858 }
859
860 /* Deadline class' related fields in a runqueue */
861 struct dl_rq {
862 /* runqueue is an rbtree, ordered by deadline */
863 struct rb_root_cached root;
864
865 unsigned int dl_nr_running;
866
867 /*
868 * Deadline values of the currently executing and the
869 * earliest ready task on this rq. Caching these facilitates
870 * the decision whether or not a ready but not running task
871 * should migrate somewhere else.
872 */
873 struct {
874 u64 curr;
875 u64 next;
876 } earliest_dl;
877
878 bool overloaded;
879
880 /*
881 * Tasks on this rq that can be pushed away. They are kept in
882 * an rb-tree, ordered by tasks' deadlines, with caching
883 * of the leftmost (earliest deadline) element.
884 */
885 struct rb_root_cached pushable_dl_tasks_root;
886
887 /*
888 * "Active utilization" for this runqueue: increased when a
889 * task wakes up (becomes TASK_RUNNING) and decreased when a
890 * task blocks
891 */
892 u64 running_bw;
893
894 /*
895 * Utilization of the tasks "assigned" to this runqueue (including
896 * the tasks that are in runqueue and the tasks that executed on this
897 * CPU and blocked). Increased when a task moves to this runqueue, and
898 * decreased when the task moves away (migrates, changes scheduling
899 * policy, or terminates).
900 * This is needed to compute the "inactive utilization" for the
901 * runqueue (inactive utilization = this_bw - running_bw).
902 */
903 u64 this_bw;
904 u64 extra_bw;
905
906 /*
907 * Maximum available bandwidth for reclaiming by SCHED_FLAG_RECLAIM
908 * tasks of this rq. Used in calculation of reclaimable bandwidth(GRUB).
909 */
910 u64 max_bw;
911
912 /*
913 * Inverse of the fraction of CPU utilization that can be reclaimed
914 * by the GRUB algorithm.
915 */
916 u64 bw_ratio;
917 };
918
919 #ifdef CONFIG_FAIR_GROUP_SCHED
920
921 /* An entity is a task if it doesn't "own" a runqueue */
922 #define entity_is_task(se) (!se->my_q)
923
se_update_runnable(struct sched_entity * se)924 static inline void se_update_runnable(struct sched_entity *se)
925 {
926 if (!entity_is_task(se))
927 se->runnable_weight = se->my_q->h_nr_runnable;
928 }
929
se_runnable(struct sched_entity * se)930 static inline long se_runnable(struct sched_entity *se)
931 {
932 if (se->sched_delayed)
933 return false;
934
935 if (entity_is_task(se))
936 return !!se->on_rq;
937 else
938 return se->runnable_weight;
939 }
940
941 #else /* !CONFIG_FAIR_GROUP_SCHED: */
942
943 #define entity_is_task(se) 1
944
se_update_runnable(struct sched_entity * se)945 static inline void se_update_runnable(struct sched_entity *se) { }
946
se_runnable(struct sched_entity * se)947 static inline long se_runnable(struct sched_entity *se)
948 {
949 if (se->sched_delayed)
950 return false;
951
952 return !!se->on_rq;
953 }
954
955 #endif /* !CONFIG_FAIR_GROUP_SCHED */
956
957 /*
958 * XXX we want to get rid of these helpers and use the full load resolution.
959 */
se_weight(struct sched_entity * se)960 static inline long se_weight(struct sched_entity *se)
961 {
962 return scale_load_down(se->load.weight);
963 }
964
965
sched_asym_prefer(int a,int b)966 static inline bool sched_asym_prefer(int a, int b)
967 {
968 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
969 }
970
971 struct perf_domain {
972 struct em_perf_domain *em_pd;
973 struct perf_domain *next;
974 struct rcu_head rcu;
975 };
976
977 /*
978 * We add the notion of a root-domain which will be used to define per-domain
979 * variables. Each exclusive cpuset essentially defines an island domain by
980 * fully partitioning the member CPUs from any other cpuset. Whenever a new
981 * exclusive cpuset is created, we also create and attach a new root-domain
982 * object.
983 *
984 */
985 struct root_domain {
986 atomic_t refcount;
987 atomic_t rto_count;
988 struct rcu_head rcu;
989 cpumask_var_t span;
990 cpumask_var_t online;
991
992 /*
993 * Indicate pullable load on at least one CPU, e.g:
994 * - More than one runnable task
995 * - Running task is misfit
996 */
997 bool overloaded;
998
999 /* Indicate one or more CPUs over-utilized (tipping point) */
1000 bool overutilized;
1001
1002 /*
1003 * The bit corresponding to a CPU gets set here if such CPU has more
1004 * than one runnable -deadline task (as it is below for RT tasks).
1005 */
1006 cpumask_var_t dlo_mask;
1007 atomic_t dlo_count;
1008 struct dl_bw dl_bw;
1009 struct cpudl cpudl;
1010
1011 /*
1012 * Indicate whether a root_domain's dl_bw has been checked or
1013 * updated. It's monotonously increasing value.
1014 *
1015 * Also, some corner cases, like 'wrap around' is dangerous, but given
1016 * that u64 is 'big enough'. So that shouldn't be a concern.
1017 */
1018 u64 visit_cookie;
1019
1020 #ifdef HAVE_RT_PUSH_IPI
1021 /*
1022 * For IPI pull requests, loop across the rto_mask.
1023 */
1024 struct irq_work rto_push_work;
1025 raw_spinlock_t rto_lock;
1026 /* These are only updated and read within rto_lock */
1027 int rto_loop;
1028 int rto_cpu;
1029 /* These atomics are updated outside of a lock */
1030 atomic_t rto_loop_next;
1031 atomic_t rto_loop_start;
1032 #endif /* HAVE_RT_PUSH_IPI */
1033 /*
1034 * The "RT overload" flag: it gets set if a CPU has more than
1035 * one runnable RT task.
1036 */
1037 cpumask_var_t rto_mask;
1038 struct cpupri cpupri;
1039
1040 /*
1041 * NULL-terminated list of performance domains intersecting with the
1042 * CPUs of the rd. Protected by RCU.
1043 */
1044 struct perf_domain __rcu *pd;
1045 };
1046
1047 extern void init_defrootdomain(void);
1048 extern int sched_init_domains(const struct cpumask *cpu_map);
1049 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
1050 extern void sched_get_rd(struct root_domain *rd);
1051 extern void sched_put_rd(struct root_domain *rd);
1052
get_rd_overloaded(struct root_domain * rd)1053 static inline int get_rd_overloaded(struct root_domain *rd)
1054 {
1055 return READ_ONCE(rd->overloaded);
1056 }
1057
set_rd_overloaded(struct root_domain * rd,int status)1058 static inline void set_rd_overloaded(struct root_domain *rd, int status)
1059 {
1060 if (get_rd_overloaded(rd) != status)
1061 WRITE_ONCE(rd->overloaded, status);
1062 }
1063
1064 #ifdef HAVE_RT_PUSH_IPI
1065 extern void rto_push_irq_work_func(struct irq_work *work);
1066 #endif
1067
1068 #ifdef CONFIG_UCLAMP_TASK
1069 /*
1070 * struct uclamp_bucket - Utilization clamp bucket
1071 * @value: utilization clamp value for tasks on this clamp bucket
1072 * @tasks: number of RUNNABLE tasks on this clamp bucket
1073 *
1074 * Keep track of how many tasks are RUNNABLE for a given utilization
1075 * clamp value.
1076 */
1077 struct uclamp_bucket {
1078 unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
1079 unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
1080 };
1081
1082 /*
1083 * struct uclamp_rq - rq's utilization clamp
1084 * @value: currently active clamp values for a rq
1085 * @bucket: utilization clamp buckets affecting a rq
1086 *
1087 * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
1088 * A clamp value is affecting a rq when there is at least one task RUNNABLE
1089 * (or actually running) with that value.
1090 *
1091 * There are up to UCLAMP_CNT possible different clamp values, currently there
1092 * are only two: minimum utilization and maximum utilization.
1093 *
1094 * All utilization clamping values are MAX aggregated, since:
1095 * - for util_min: we want to run the CPU at least at the max of the minimum
1096 * utilization required by its currently RUNNABLE tasks.
1097 * - for util_max: we want to allow the CPU to run up to the max of the
1098 * maximum utilization allowed by its currently RUNNABLE tasks.
1099 *
1100 * Since on each system we expect only a limited number of different
1101 * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
1102 * the metrics required to compute all the per-rq utilization clamp values.
1103 */
1104 struct uclamp_rq {
1105 unsigned int value;
1106 struct uclamp_bucket bucket[UCLAMP_BUCKETS];
1107 };
1108
1109 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
1110 #endif /* CONFIG_UCLAMP_TASK */
1111
1112 /*
1113 * This is the main, per-CPU runqueue data structure.
1114 *
1115 * Locking rule: those places that want to lock multiple runqueues
1116 * (such as the load balancing or the thread migration code), lock
1117 * acquire operations must be ordered by ascending &runqueue.
1118 */
1119 struct rq {
1120 /* runqueue lock: */
1121 raw_spinlock_t __lock;
1122
1123 /* Per class runqueue modification mask; bits in class order. */
1124 unsigned int queue_mask;
1125 unsigned int nr_running;
1126 #ifdef CONFIG_NUMA_BALANCING
1127 unsigned int nr_numa_running;
1128 unsigned int nr_preferred_running;
1129 unsigned int numa_migrate_on;
1130 #endif
1131 #ifdef CONFIG_NO_HZ_COMMON
1132 unsigned long last_blocked_load_update_tick;
1133 unsigned int has_blocked_load;
1134 call_single_data_t nohz_csd;
1135 unsigned int nohz_tick_stopped;
1136 atomic_t nohz_flags;
1137 #endif /* CONFIG_NO_HZ_COMMON */
1138
1139 unsigned int ttwu_pending;
1140 u64 nr_switches;
1141
1142 #ifdef CONFIG_UCLAMP_TASK
1143 /* Utilization clamp values based on CPU's RUNNABLE tasks */
1144 struct uclamp_rq uclamp[UCLAMP_CNT] ____cacheline_aligned;
1145 unsigned int uclamp_flags;
1146 #define UCLAMP_FLAG_IDLE 0x01
1147 #endif
1148
1149 struct cfs_rq cfs;
1150 struct rt_rq rt;
1151 struct dl_rq dl;
1152 #ifdef CONFIG_SCHED_CLASS_EXT
1153 struct scx_rq scx;
1154 #endif
1155
1156 struct sched_dl_entity fair_server;
1157
1158 #ifdef CONFIG_FAIR_GROUP_SCHED
1159 /* list of leaf cfs_rq on this CPU: */
1160 struct list_head leaf_cfs_rq_list;
1161 struct list_head *tmp_alone_branch;
1162 #endif /* CONFIG_FAIR_GROUP_SCHED */
1163
1164 /*
1165 * This is part of a global counter where only the total sum
1166 * over all CPUs matters. A task can increase this counter on
1167 * one CPU and if it got migrated afterwards it may decrease
1168 * it on another CPU. Always updated under the runqueue lock:
1169 */
1170 unsigned long nr_uninterruptible;
1171
1172 #ifdef CONFIG_SCHED_PROXY_EXEC
1173 struct task_struct __rcu *donor; /* Scheduling context */
1174 struct task_struct __rcu *curr; /* Execution context */
1175 #else
1176 union {
1177 struct task_struct __rcu *donor; /* Scheduler context */
1178 struct task_struct __rcu *curr; /* Execution context */
1179 };
1180 #endif
1181 struct sched_dl_entity *dl_server;
1182 struct task_struct *idle;
1183 struct task_struct *stop;
1184 unsigned long next_balance;
1185 struct mm_struct *prev_mm;
1186
1187 unsigned int clock_update_flags;
1188 u64 clock;
1189 /* Ensure that all clocks are in the same cache line */
1190 u64 clock_task ____cacheline_aligned;
1191 u64 clock_pelt;
1192 unsigned long lost_idle_time;
1193 u64 clock_pelt_idle;
1194 u64 clock_idle;
1195 #ifndef CONFIG_64BIT
1196 u64 clock_pelt_idle_copy;
1197 u64 clock_idle_copy;
1198 #endif
1199
1200 atomic_t nr_iowait;
1201
1202 u64 last_seen_need_resched_ns;
1203 int ticks_without_resched;
1204
1205 #ifdef CONFIG_MEMBARRIER
1206 int membarrier_state;
1207 #endif
1208
1209 struct root_domain *rd;
1210 struct sched_domain __rcu *sd;
1211
1212 unsigned long cpu_capacity;
1213
1214 struct balance_callback *balance_callback;
1215
1216 unsigned char nohz_idle_balance;
1217 unsigned char idle_balance;
1218
1219 unsigned long misfit_task_load;
1220
1221 /* For active balancing */
1222 int active_balance;
1223 int push_cpu;
1224 struct cpu_stop_work active_balance_work;
1225
1226 /* CPU of this runqueue: */
1227 int cpu;
1228 int online;
1229
1230 struct list_head cfs_tasks;
1231
1232 struct sched_avg avg_rt;
1233 struct sched_avg avg_dl;
1234 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
1235 struct sched_avg avg_irq;
1236 #endif
1237 #ifdef CONFIG_SCHED_HW_PRESSURE
1238 struct sched_avg avg_hw;
1239 #endif
1240 u64 idle_stamp;
1241 u64 avg_idle;
1242
1243 /* This is used to determine avg_idle's max value */
1244 u64 max_idle_balance_cost;
1245
1246 #ifdef CONFIG_HOTPLUG_CPU
1247 struct rcuwait hotplug_wait;
1248 #endif
1249
1250 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1251 u64 prev_irq_time;
1252 u64 psi_irq_time;
1253 #endif
1254 #ifdef CONFIG_PARAVIRT
1255 u64 prev_steal_time;
1256 #endif
1257 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
1258 u64 prev_steal_time_rq;
1259 #endif
1260
1261 /* calc_load related fields */
1262 unsigned long calc_load_update;
1263 long calc_load_active;
1264
1265 #ifdef CONFIG_SCHED_HRTICK
1266 call_single_data_t hrtick_csd;
1267 struct hrtimer hrtick_timer;
1268 ktime_t hrtick_time;
1269 #endif
1270
1271 #ifdef CONFIG_SCHEDSTATS
1272 /* latency stats */
1273 struct sched_info rq_sched_info;
1274 unsigned long long rq_cpu_time;
1275
1276 /* sys_sched_yield() stats */
1277 unsigned int yld_count;
1278
1279 /* schedule() stats */
1280 unsigned int sched_count;
1281 unsigned int sched_goidle;
1282
1283 /* try_to_wake_up() stats */
1284 unsigned int ttwu_count;
1285 unsigned int ttwu_local;
1286 #endif
1287
1288 #ifdef CONFIG_CPU_IDLE
1289 /* Must be inspected within a RCU lock section */
1290 struct cpuidle_state *idle_state;
1291 #endif
1292
1293 unsigned int nr_pinned;
1294 unsigned int push_busy;
1295 struct cpu_stop_work push_work;
1296
1297 #ifdef CONFIG_SCHED_CORE
1298 /* per rq */
1299 struct rq *core;
1300 struct task_struct *core_pick;
1301 struct sched_dl_entity *core_dl_server;
1302 unsigned int core_enabled;
1303 unsigned int core_sched_seq;
1304 struct rb_root core_tree;
1305
1306 /* shared state -- careful with sched_core_cpu_deactivate() */
1307 unsigned int core_task_seq;
1308 unsigned int core_pick_seq;
1309 unsigned long core_cookie;
1310 unsigned int core_forceidle_count;
1311 unsigned int core_forceidle_seq;
1312 unsigned int core_forceidle_occupation;
1313 u64 core_forceidle_start;
1314 #endif /* CONFIG_SCHED_CORE */
1315
1316 /* Scratch cpumask to be temporarily used under rq_lock */
1317 cpumask_var_t scratch_mask;
1318
1319 #ifdef CONFIG_CFS_BANDWIDTH
1320 call_single_data_t cfsb_csd;
1321 struct list_head cfsb_csd_list;
1322 #endif
1323 };
1324
1325 #ifdef CONFIG_FAIR_GROUP_SCHED
1326
1327 /* CPU runqueue to which this cfs_rq is attached */
rq_of(struct cfs_rq * cfs_rq)1328 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1329 {
1330 return cfs_rq->rq;
1331 }
1332
1333 #else /* !CONFIG_FAIR_GROUP_SCHED: */
1334
rq_of(struct cfs_rq * cfs_rq)1335 static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1336 {
1337 return container_of(cfs_rq, struct rq, cfs);
1338 }
1339 #endif /* !CONFIG_FAIR_GROUP_SCHED */
1340
cpu_of(struct rq * rq)1341 static inline int cpu_of(struct rq *rq)
1342 {
1343 return rq->cpu;
1344 }
1345
1346 #define MDF_PUSH 0x01
1347
is_migration_disabled(struct task_struct * p)1348 static inline bool is_migration_disabled(struct task_struct *p)
1349 {
1350 return p->migration_disabled;
1351 }
1352
1353 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1354 DECLARE_PER_CPU(struct rnd_state, sched_rnd_state);
1355
sched_rng(void)1356 static inline u32 sched_rng(void)
1357 {
1358 return prandom_u32_state(this_cpu_ptr(&sched_rnd_state));
1359 }
1360
1361 #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
1362 #define this_rq() this_cpu_ptr(&runqueues)
1363 #define task_rq(p) cpu_rq(task_cpu(p))
1364 #define cpu_curr(cpu) (cpu_rq(cpu)->curr)
1365 #define raw_rq() raw_cpu_ptr(&runqueues)
1366
1367 #ifdef CONFIG_SCHED_PROXY_EXEC
rq_set_donor(struct rq * rq,struct task_struct * t)1368 static inline void rq_set_donor(struct rq *rq, struct task_struct *t)
1369 {
1370 rcu_assign_pointer(rq->donor, t);
1371 }
1372 #else
rq_set_donor(struct rq * rq,struct task_struct * t)1373 static inline void rq_set_donor(struct rq *rq, struct task_struct *t)
1374 {
1375 /* Do nothing */
1376 }
1377 #endif
1378
1379 #ifdef CONFIG_SCHED_CORE
1380 static inline struct cpumask *sched_group_span(struct sched_group *sg);
1381
1382 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled);
1383
sched_core_enabled(struct rq * rq)1384 static inline bool sched_core_enabled(struct rq *rq)
1385 {
1386 return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled;
1387 }
1388
sched_core_disabled(void)1389 static inline bool sched_core_disabled(void)
1390 {
1391 return !static_branch_unlikely(&__sched_core_enabled);
1392 }
1393
1394 /*
1395 * Be careful with this function; not for general use. The return value isn't
1396 * stable unless you actually hold a relevant rq->__lock.
1397 */
rq_lockp(struct rq * rq)1398 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1399 {
1400 if (sched_core_enabled(rq))
1401 return &rq->core->__lock;
1402
1403 return &rq->__lock;
1404 }
1405
__rq_lockp(struct rq * rq)1406 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1407 {
1408 if (rq->core_enabled)
1409 return &rq->core->__lock;
1410
1411 return &rq->__lock;
1412 }
1413
1414 extern bool
1415 cfs_prio_less(const struct task_struct *a, const struct task_struct *b, bool fi);
1416
1417 extern void task_vruntime_update(struct rq *rq, struct task_struct *p, bool in_fi);
1418
1419 /*
1420 * Helpers to check if the CPU's core cookie matches with the task's cookie
1421 * when core scheduling is enabled.
1422 * A special case is that the task's cookie always matches with CPU's core
1423 * cookie if the CPU is in an idle core.
1424 */
sched_cpu_cookie_match(struct rq * rq,struct task_struct * p)1425 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1426 {
1427 /* Ignore cookie match if core scheduler is not enabled on the CPU. */
1428 if (!sched_core_enabled(rq))
1429 return true;
1430
1431 return rq->core->core_cookie == p->core_cookie;
1432 }
1433
sched_core_cookie_match(struct rq * rq,struct task_struct * p)1434 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1435 {
1436 bool idle_core = true;
1437 int cpu;
1438
1439 /* Ignore cookie match if core scheduler is not enabled on the CPU. */
1440 if (!sched_core_enabled(rq))
1441 return true;
1442
1443 if (rq->core->core_cookie == p->core_cookie)
1444 return true;
1445
1446 for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) {
1447 if (!available_idle_cpu(cpu)) {
1448 idle_core = false;
1449 break;
1450 }
1451 }
1452
1453 /*
1454 * A CPU in an idle core is always the best choice for tasks with
1455 * cookies.
1456 */
1457 return idle_core;
1458 }
1459
sched_group_cookie_match(struct rq * rq,struct task_struct * p,struct sched_group * group)1460 static inline bool sched_group_cookie_match(struct rq *rq,
1461 struct task_struct *p,
1462 struct sched_group *group)
1463 {
1464 int cpu;
1465
1466 /* Ignore cookie match if core scheduler is not enabled on the CPU. */
1467 if (!sched_core_enabled(rq))
1468 return true;
1469
1470 for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
1471 if (sched_core_cookie_match(cpu_rq(cpu), p))
1472 return true;
1473 }
1474 return false;
1475 }
1476
sched_core_enqueued(struct task_struct * p)1477 static inline bool sched_core_enqueued(struct task_struct *p)
1478 {
1479 return !RB_EMPTY_NODE(&p->core_node);
1480 }
1481
1482 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p);
1483 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags);
1484
1485 extern void sched_core_get(void);
1486 extern void sched_core_put(void);
1487
1488 #else /* !CONFIG_SCHED_CORE: */
1489
sched_core_enabled(struct rq * rq)1490 static inline bool sched_core_enabled(struct rq *rq)
1491 {
1492 return false;
1493 }
1494
sched_core_disabled(void)1495 static inline bool sched_core_disabled(void)
1496 {
1497 return true;
1498 }
1499
rq_lockp(struct rq * rq)1500 static inline raw_spinlock_t *rq_lockp(struct rq *rq)
1501 {
1502 return &rq->__lock;
1503 }
1504
__rq_lockp(struct rq * rq)1505 static inline raw_spinlock_t *__rq_lockp(struct rq *rq)
1506 {
1507 return &rq->__lock;
1508 }
1509
sched_cpu_cookie_match(struct rq * rq,struct task_struct * p)1510 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p)
1511 {
1512 return true;
1513 }
1514
sched_core_cookie_match(struct rq * rq,struct task_struct * p)1515 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p)
1516 {
1517 return true;
1518 }
1519
sched_group_cookie_match(struct rq * rq,struct task_struct * p,struct sched_group * group)1520 static inline bool sched_group_cookie_match(struct rq *rq,
1521 struct task_struct *p,
1522 struct sched_group *group)
1523 {
1524 return true;
1525 }
1526
1527 #endif /* !CONFIG_SCHED_CORE */
1528
1529 #ifdef CONFIG_RT_GROUP_SCHED
1530 # ifdef CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED
1531 DECLARE_STATIC_KEY_FALSE(rt_group_sched);
rt_group_sched_enabled(void)1532 static inline bool rt_group_sched_enabled(void)
1533 {
1534 return static_branch_unlikely(&rt_group_sched);
1535 }
1536 # else /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED: */
1537 DECLARE_STATIC_KEY_TRUE(rt_group_sched);
rt_group_sched_enabled(void)1538 static inline bool rt_group_sched_enabled(void)
1539 {
1540 return static_branch_likely(&rt_group_sched);
1541 }
1542 # endif /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED */
1543 #else /* !CONFIG_RT_GROUP_SCHED: */
1544 # define rt_group_sched_enabled() false
1545 #endif /* !CONFIG_RT_GROUP_SCHED */
1546
lockdep_assert_rq_held(struct rq * rq)1547 static inline void lockdep_assert_rq_held(struct rq *rq)
1548 {
1549 lockdep_assert_held(__rq_lockp(rq));
1550 }
1551
1552 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass);
1553 extern bool raw_spin_rq_trylock(struct rq *rq);
1554 extern void raw_spin_rq_unlock(struct rq *rq);
1555
raw_spin_rq_lock(struct rq * rq)1556 static inline void raw_spin_rq_lock(struct rq *rq)
1557 {
1558 raw_spin_rq_lock_nested(rq, 0);
1559 }
1560
raw_spin_rq_lock_irq(struct rq * rq)1561 static inline void raw_spin_rq_lock_irq(struct rq *rq)
1562 {
1563 local_irq_disable();
1564 raw_spin_rq_lock(rq);
1565 }
1566
raw_spin_rq_unlock_irq(struct rq * rq)1567 static inline void raw_spin_rq_unlock_irq(struct rq *rq)
1568 {
1569 raw_spin_rq_unlock(rq);
1570 local_irq_enable();
1571 }
1572
_raw_spin_rq_lock_irqsave(struct rq * rq)1573 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq)
1574 {
1575 unsigned long flags;
1576
1577 local_irq_save(flags);
1578 raw_spin_rq_lock(rq);
1579
1580 return flags;
1581 }
1582
raw_spin_rq_unlock_irqrestore(struct rq * rq,unsigned long flags)1583 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags)
1584 {
1585 raw_spin_rq_unlock(rq);
1586 local_irq_restore(flags);
1587 }
1588
1589 #define raw_spin_rq_lock_irqsave(rq, flags) \
1590 do { \
1591 flags = _raw_spin_rq_lock_irqsave(rq); \
1592 } while (0)
1593
1594 #ifdef CONFIG_SCHED_SMT
1595 extern void __update_idle_core(struct rq *rq);
1596
update_idle_core(struct rq * rq)1597 static inline void update_idle_core(struct rq *rq)
1598 {
1599 if (static_branch_unlikely(&sched_smt_present))
1600 __update_idle_core(rq);
1601 }
1602
1603 #else /* !CONFIG_SCHED_SMT: */
update_idle_core(struct rq * rq)1604 static inline void update_idle_core(struct rq *rq) { }
1605 #endif /* !CONFIG_SCHED_SMT */
1606
1607 #ifdef CONFIG_FAIR_GROUP_SCHED
1608
task_of(struct sched_entity * se)1609 static inline struct task_struct *task_of(struct sched_entity *se)
1610 {
1611 WARN_ON_ONCE(!entity_is_task(se));
1612 return container_of(se, struct task_struct, se);
1613 }
1614
task_cfs_rq(struct task_struct * p)1615 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
1616 {
1617 return p->se.cfs_rq;
1618 }
1619
1620 /* runqueue on which this entity is (to be) queued */
cfs_rq_of(const struct sched_entity * se)1621 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1622 {
1623 return se->cfs_rq;
1624 }
1625
1626 /* runqueue "owned" by this group */
group_cfs_rq(struct sched_entity * grp)1627 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1628 {
1629 return grp->my_q;
1630 }
1631
1632 #else /* !CONFIG_FAIR_GROUP_SCHED: */
1633
1634 #define task_of(_se) container_of(_se, struct task_struct, se)
1635
task_cfs_rq(const struct task_struct * p)1636 static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p)
1637 {
1638 return &task_rq(p)->cfs;
1639 }
1640
cfs_rq_of(const struct sched_entity * se)1641 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se)
1642 {
1643 const struct task_struct *p = task_of(se);
1644 struct rq *rq = task_rq(p);
1645
1646 return &rq->cfs;
1647 }
1648
1649 /* runqueue "owned" by this group */
group_cfs_rq(struct sched_entity * grp)1650 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
1651 {
1652 return NULL;
1653 }
1654
1655 #endif /* !CONFIG_FAIR_GROUP_SCHED */
1656
1657 extern void update_rq_clock(struct rq *rq);
1658
1659 /*
1660 * rq::clock_update_flags bits
1661 *
1662 * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1663 * call to __schedule(). This is an optimisation to avoid
1664 * neighbouring rq clock updates.
1665 *
1666 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1667 * in effect and calls to update_rq_clock() are being ignored.
1668 *
1669 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1670 * made to update_rq_clock() since the last time rq::lock was pinned.
1671 *
1672 * If inside of __schedule(), clock_update_flags will have been
1673 * shifted left (a left shift is a cheap operation for the fast path
1674 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1675 *
1676 * if (rq-clock_update_flags >= RQCF_UPDATED)
1677 *
1678 * to check if %RQCF_UPDATED is set. It'll never be shifted more than
1679 * one position though, because the next rq_unpin_lock() will shift it
1680 * back.
1681 */
1682 #define RQCF_REQ_SKIP 0x01
1683 #define RQCF_ACT_SKIP 0x02
1684 #define RQCF_UPDATED 0x04
1685
assert_clock_updated(struct rq * rq)1686 static inline void assert_clock_updated(struct rq *rq)
1687 {
1688 /*
1689 * The only reason for not seeing a clock update since the
1690 * last rq_pin_lock() is if we're currently skipping updates.
1691 */
1692 WARN_ON_ONCE(rq->clock_update_flags < RQCF_ACT_SKIP);
1693 }
1694
rq_clock(struct rq * rq)1695 static inline u64 rq_clock(struct rq *rq)
1696 {
1697 lockdep_assert_rq_held(rq);
1698 assert_clock_updated(rq);
1699
1700 return rq->clock;
1701 }
1702
rq_clock_task(struct rq * rq)1703 static inline u64 rq_clock_task(struct rq *rq)
1704 {
1705 lockdep_assert_rq_held(rq);
1706 assert_clock_updated(rq);
1707
1708 return rq->clock_task;
1709 }
1710
rq_clock_skip_update(struct rq * rq)1711 static inline void rq_clock_skip_update(struct rq *rq)
1712 {
1713 lockdep_assert_rq_held(rq);
1714 rq->clock_update_flags |= RQCF_REQ_SKIP;
1715 }
1716
1717 /*
1718 * See rt task throttling, which is the only time a skip
1719 * request is canceled.
1720 */
rq_clock_cancel_skipupdate(struct rq * rq)1721 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1722 {
1723 lockdep_assert_rq_held(rq);
1724 rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1725 }
1726
1727 /*
1728 * During cpu offlining and rq wide unthrottling, we can trigger
1729 * an update_rq_clock() for several cfs and rt runqueues (Typically
1730 * when using list_for_each_entry_*)
1731 * rq_clock_start_loop_update() can be called after updating the clock
1732 * once and before iterating over the list to prevent multiple update.
1733 * After the iterative traversal, we need to call rq_clock_stop_loop_update()
1734 * to clear RQCF_ACT_SKIP of rq->clock_update_flags.
1735 */
rq_clock_start_loop_update(struct rq * rq)1736 static inline void rq_clock_start_loop_update(struct rq *rq)
1737 {
1738 lockdep_assert_rq_held(rq);
1739 WARN_ON_ONCE(rq->clock_update_flags & RQCF_ACT_SKIP);
1740 rq->clock_update_flags |= RQCF_ACT_SKIP;
1741 }
1742
rq_clock_stop_loop_update(struct rq * rq)1743 static inline void rq_clock_stop_loop_update(struct rq *rq)
1744 {
1745 lockdep_assert_rq_held(rq);
1746 rq->clock_update_flags &= ~RQCF_ACT_SKIP;
1747 }
1748
1749 struct rq_flags {
1750 unsigned long flags;
1751 struct pin_cookie cookie;
1752 /*
1753 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1754 * current pin context is stashed here in case it needs to be
1755 * restored in rq_repin_lock().
1756 */
1757 unsigned int clock_update_flags;
1758 };
1759
1760 extern struct balance_callback balance_push_callback;
1761
1762 #ifdef CONFIG_SCHED_CLASS_EXT
1763 extern const struct sched_class ext_sched_class;
1764
1765 DECLARE_STATIC_KEY_FALSE(__scx_enabled); /* SCX BPF scheduler loaded */
1766 DECLARE_STATIC_KEY_FALSE(__scx_switched_all); /* all fair class tasks on SCX */
1767
1768 #define scx_enabled() static_branch_unlikely(&__scx_enabled)
1769 #define scx_switched_all() static_branch_unlikely(&__scx_switched_all)
1770
scx_rq_clock_update(struct rq * rq,u64 clock)1771 static inline void scx_rq_clock_update(struct rq *rq, u64 clock)
1772 {
1773 if (!scx_enabled())
1774 return;
1775 WRITE_ONCE(rq->scx.clock, clock);
1776 smp_store_release(&rq->scx.flags, rq->scx.flags | SCX_RQ_CLK_VALID);
1777 }
1778
scx_rq_clock_invalidate(struct rq * rq)1779 static inline void scx_rq_clock_invalidate(struct rq *rq)
1780 {
1781 if (!scx_enabled())
1782 return;
1783 WRITE_ONCE(rq->scx.flags, rq->scx.flags & ~SCX_RQ_CLK_VALID);
1784 }
1785
1786 #else /* !CONFIG_SCHED_CLASS_EXT: */
1787 #define scx_enabled() false
1788 #define scx_switched_all() false
1789
scx_rq_clock_update(struct rq * rq,u64 clock)1790 static inline void scx_rq_clock_update(struct rq *rq, u64 clock) {}
scx_rq_clock_invalidate(struct rq * rq)1791 static inline void scx_rq_clock_invalidate(struct rq *rq) {}
1792 #endif /* !CONFIG_SCHED_CLASS_EXT */
1793
1794 /*
1795 * Lockdep annotation that avoids accidental unlocks; it's like a
1796 * sticky/continuous lockdep_assert_held().
1797 *
1798 * This avoids code that has access to 'struct rq *rq' (basically everything in
1799 * the scheduler) from accidentally unlocking the rq if they do not also have a
1800 * copy of the (on-stack) 'struct rq_flags rf'.
1801 *
1802 * Also see Documentation/locking/lockdep-design.rst.
1803 */
rq_pin_lock(struct rq * rq,struct rq_flags * rf)1804 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1805 {
1806 rf->cookie = lockdep_pin_lock(__rq_lockp(rq));
1807
1808 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1809 rf->clock_update_flags = 0;
1810 WARN_ON_ONCE(rq->balance_callback && rq->balance_callback != &balance_push_callback);
1811 }
1812
rq_unpin_lock(struct rq * rq,struct rq_flags * rf)1813 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1814 {
1815 if (rq->clock_update_flags > RQCF_ACT_SKIP)
1816 rf->clock_update_flags = RQCF_UPDATED;
1817
1818 scx_rq_clock_invalidate(rq);
1819 lockdep_unpin_lock(__rq_lockp(rq), rf->cookie);
1820 }
1821
rq_repin_lock(struct rq * rq,struct rq_flags * rf)1822 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1823 {
1824 lockdep_repin_lock(__rq_lockp(rq), rf->cookie);
1825
1826 /*
1827 * Restore the value we stashed in @rf for this pin context.
1828 */
1829 rq->clock_update_flags |= rf->clock_update_flags;
1830 }
1831
1832 extern
1833 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1834 __acquires(rq->lock);
1835
1836 extern
1837 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1838 __acquires(p->pi_lock)
1839 __acquires(rq->lock);
1840
1841 static inline void
__task_rq_unlock(struct rq * rq,struct task_struct * p,struct rq_flags * rf)1842 __task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1843 __releases(rq->lock)
1844 {
1845 rq_unpin_lock(rq, rf);
1846 raw_spin_rq_unlock(rq);
1847 }
1848
1849 static inline void
task_rq_unlock(struct rq * rq,struct task_struct * p,struct rq_flags * rf)1850 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1851 __releases(rq->lock)
1852 __releases(p->pi_lock)
1853 {
1854 __task_rq_unlock(rq, p, rf);
1855 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1856 }
1857
1858 DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct,
1859 _T->rq = task_rq_lock(_T->lock, &_T->rf),
1860 task_rq_unlock(_T->rq, _T->lock, &_T->rf),
1861 struct rq *rq; struct rq_flags rf)
1862
1863 DEFINE_LOCK_GUARD_1(__task_rq_lock, struct task_struct,
1864 _T->rq = __task_rq_lock(_T->lock, &_T->rf),
1865 __task_rq_unlock(_T->rq, _T->lock, &_T->rf),
1866 struct rq *rq; struct rq_flags rf)
1867
rq_lock_irqsave(struct rq * rq,struct rq_flags * rf)1868 static inline void rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1869 __acquires(rq->lock)
1870 {
1871 raw_spin_rq_lock_irqsave(rq, rf->flags);
1872 rq_pin_lock(rq, rf);
1873 }
1874
rq_lock_irq(struct rq * rq,struct rq_flags * rf)1875 static inline void rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1876 __acquires(rq->lock)
1877 {
1878 raw_spin_rq_lock_irq(rq);
1879 rq_pin_lock(rq, rf);
1880 }
1881
rq_lock(struct rq * rq,struct rq_flags * rf)1882 static inline void rq_lock(struct rq *rq, struct rq_flags *rf)
1883 __acquires(rq->lock)
1884 {
1885 raw_spin_rq_lock(rq);
1886 rq_pin_lock(rq, rf);
1887 }
1888
rq_unlock_irqrestore(struct rq * rq,struct rq_flags * rf)1889 static inline void rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1890 __releases(rq->lock)
1891 {
1892 rq_unpin_lock(rq, rf);
1893 raw_spin_rq_unlock_irqrestore(rq, rf->flags);
1894 }
1895
rq_unlock_irq(struct rq * rq,struct rq_flags * rf)1896 static inline void rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1897 __releases(rq->lock)
1898 {
1899 rq_unpin_lock(rq, rf);
1900 raw_spin_rq_unlock_irq(rq);
1901 }
1902
rq_unlock(struct rq * rq,struct rq_flags * rf)1903 static inline void rq_unlock(struct rq *rq, struct rq_flags *rf)
1904 __releases(rq->lock)
1905 {
1906 rq_unpin_lock(rq, rf);
1907 raw_spin_rq_unlock(rq);
1908 }
1909
1910 DEFINE_LOCK_GUARD_1(rq_lock, struct rq,
1911 rq_lock(_T->lock, &_T->rf),
1912 rq_unlock(_T->lock, &_T->rf),
1913 struct rq_flags rf)
1914
1915 DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq,
1916 rq_lock_irq(_T->lock, &_T->rf),
1917 rq_unlock_irq(_T->lock, &_T->rf),
1918 struct rq_flags rf)
1919
1920 DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq,
1921 rq_lock_irqsave(_T->lock, &_T->rf),
1922 rq_unlock_irqrestore(_T->lock, &_T->rf),
1923 struct rq_flags rf)
1924
this_rq_lock_irq(struct rq_flags * rf)1925 static inline struct rq *this_rq_lock_irq(struct rq_flags *rf)
1926 __acquires(rq->lock)
1927 {
1928 struct rq *rq;
1929
1930 local_irq_disable();
1931 rq = this_rq();
1932 rq_lock(rq, rf);
1933
1934 return rq;
1935 }
1936
1937 #ifdef CONFIG_NUMA
1938
1939 enum numa_topology_type {
1940 NUMA_DIRECT,
1941 NUMA_GLUELESS_MESH,
1942 NUMA_BACKPLANE,
1943 };
1944
1945 extern enum numa_topology_type sched_numa_topology_type;
1946 extern int sched_max_numa_distance;
1947 extern bool find_numa_distance(int distance);
1948 extern void sched_init_numa(int offline_node);
1949 extern void sched_update_numa(int cpu, bool online);
1950 extern void sched_domains_numa_masks_set(unsigned int cpu);
1951 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1952 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1953
1954 #else /* !CONFIG_NUMA: */
1955
sched_init_numa(int offline_node)1956 static inline void sched_init_numa(int offline_node) { }
sched_update_numa(int cpu,bool online)1957 static inline void sched_update_numa(int cpu, bool online) { }
sched_domains_numa_masks_set(unsigned int cpu)1958 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
sched_domains_numa_masks_clear(unsigned int cpu)1959 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1960
sched_numa_find_closest(const struct cpumask * cpus,int cpu)1961 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1962 {
1963 return nr_cpu_ids;
1964 }
1965
1966 #endif /* !CONFIG_NUMA */
1967
1968 #ifdef CONFIG_NUMA_BALANCING
1969
1970 /* The regions in numa_faults array from task_struct */
1971 enum numa_faults_stats {
1972 NUMA_MEM = 0,
1973 NUMA_CPU,
1974 NUMA_MEMBUF,
1975 NUMA_CPUBUF
1976 };
1977
1978 extern void sched_setnuma(struct task_struct *p, int node);
1979 extern int migrate_task_to(struct task_struct *p, int cpu);
1980 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1981 int cpu, int scpu);
1982 extern void init_numa_balancing(u64 clone_flags, struct task_struct *p);
1983
1984 #else /* !CONFIG_NUMA_BALANCING: */
1985
1986 static inline void
init_numa_balancing(u64 clone_flags,struct task_struct * p)1987 init_numa_balancing(u64 clone_flags, struct task_struct *p)
1988 {
1989 }
1990
1991 #endif /* !CONFIG_NUMA_BALANCING */
1992
1993 static inline void
queue_balance_callback(struct rq * rq,struct balance_callback * head,void (* func)(struct rq * rq))1994 queue_balance_callback(struct rq *rq,
1995 struct balance_callback *head,
1996 void (*func)(struct rq *rq))
1997 {
1998 lockdep_assert_rq_held(rq);
1999
2000 /*
2001 * Don't (re)queue an already queued item; nor queue anything when
2002 * balance_push() is active, see the comment with
2003 * balance_push_callback.
2004 */
2005 if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
2006 return;
2007
2008 head->func = func;
2009 head->next = rq->balance_callback;
2010 rq->balance_callback = head;
2011 }
2012
2013 #define rcu_dereference_check_sched_domain(p) \
2014 rcu_dereference_check((p), lockdep_is_held(&sched_domains_mutex))
2015
2016 /*
2017 * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
2018 * See destroy_sched_domains: call_rcu for details.
2019 *
2020 * The domain tree of any CPU may only be accessed from within
2021 * preempt-disabled sections.
2022 */
2023 #define for_each_domain(cpu, __sd) \
2024 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
2025 __sd; __sd = __sd->parent)
2026
2027 /* A mask of all the SD flags that have the SDF_SHARED_CHILD metaflag */
2028 #define SD_FLAG(name, mflags) (name * !!((mflags) & SDF_SHARED_CHILD)) |
2029 static const unsigned int SD_SHARED_CHILD_MASK =
2030 #include <linux/sched/sd_flags.h>
2031 0;
2032 #undef SD_FLAG
2033
2034 /**
2035 * highest_flag_domain - Return highest sched_domain containing flag.
2036 * @cpu: The CPU whose highest level of sched domain is to
2037 * be returned.
2038 * @flag: The flag to check for the highest sched_domain
2039 * for the given CPU.
2040 *
2041 * Returns the highest sched_domain of a CPU which contains @flag. If @flag has
2042 * the SDF_SHARED_CHILD metaflag, all the children domains also have @flag.
2043 */
highest_flag_domain(int cpu,int flag)2044 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
2045 {
2046 struct sched_domain *sd, *hsd = NULL;
2047
2048 for_each_domain(cpu, sd) {
2049 if (sd->flags & flag) {
2050 hsd = sd;
2051 continue;
2052 }
2053
2054 /*
2055 * Stop the search if @flag is known to be shared at lower
2056 * levels. It will not be found further up.
2057 */
2058 if (flag & SD_SHARED_CHILD_MASK)
2059 break;
2060 }
2061
2062 return hsd;
2063 }
2064
lowest_flag_domain(int cpu,int flag)2065 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
2066 {
2067 struct sched_domain *sd;
2068
2069 for_each_domain(cpu, sd) {
2070 if (sd->flags & flag)
2071 break;
2072 }
2073
2074 return sd;
2075 }
2076
2077 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
2078 DECLARE_PER_CPU(int, sd_llc_size);
2079 DECLARE_PER_CPU(int, sd_llc_id);
2080 DECLARE_PER_CPU(int, sd_share_id);
2081 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
2082 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
2083 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
2084 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
2085
2086 extern struct static_key_false sched_asym_cpucapacity;
2087 extern struct static_key_false sched_cluster_active;
2088
sched_asym_cpucap_active(void)2089 static __always_inline bool sched_asym_cpucap_active(void)
2090 {
2091 return static_branch_unlikely(&sched_asym_cpucapacity);
2092 }
2093
2094 struct sched_group_capacity {
2095 atomic_t ref;
2096 /*
2097 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
2098 * for a single CPU.
2099 */
2100 unsigned long capacity;
2101 unsigned long min_capacity; /* Min per-CPU capacity in group */
2102 unsigned long max_capacity; /* Max per-CPU capacity in group */
2103 unsigned long next_update;
2104 int imbalance; /* XXX unrelated to capacity but shared group state */
2105
2106 int id;
2107
2108 unsigned long cpumask[]; /* Balance mask */
2109 };
2110
2111 struct sched_group {
2112 struct sched_group *next; /* Must be a circular list */
2113 atomic_t ref;
2114
2115 unsigned int group_weight;
2116 unsigned int cores;
2117 struct sched_group_capacity *sgc;
2118 int asym_prefer_cpu; /* CPU of highest priority in group */
2119 int flags;
2120
2121 /*
2122 * The CPUs this group covers.
2123 *
2124 * NOTE: this field is variable length. (Allocated dynamically
2125 * by attaching extra space to the end of the structure,
2126 * depending on how many CPUs the kernel has booted up with)
2127 */
2128 unsigned long cpumask[];
2129 };
2130
sched_group_span(struct sched_group * sg)2131 static inline struct cpumask *sched_group_span(struct sched_group *sg)
2132 {
2133 return to_cpumask(sg->cpumask);
2134 }
2135
2136 /*
2137 * See build_balance_mask().
2138 */
group_balance_mask(struct sched_group * sg)2139 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
2140 {
2141 return to_cpumask(sg->sgc->cpumask);
2142 }
2143
2144 extern int group_balance_cpu(struct sched_group *sg);
2145
2146 extern void update_sched_domain_debugfs(void);
2147 extern void dirty_sched_domain_sysctl(int cpu);
2148
2149 extern int sched_update_scaling(void);
2150
task_user_cpus(struct task_struct * p)2151 static inline const struct cpumask *task_user_cpus(struct task_struct *p)
2152 {
2153 if (!p->user_cpus_ptr)
2154 return cpu_possible_mask; /* &init_task.cpus_mask */
2155 return p->user_cpus_ptr;
2156 }
2157
2158 #ifdef CONFIG_CGROUP_SCHED
2159
2160 /*
2161 * Return the group to which this tasks belongs.
2162 *
2163 * We cannot use task_css() and friends because the cgroup subsystem
2164 * changes that value before the cgroup_subsys::attach() method is called,
2165 * therefore we cannot pin it and might observe the wrong value.
2166 *
2167 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
2168 * core changes this before calling sched_move_task().
2169 *
2170 * Instead we use a 'copy' which is updated from sched_move_task() while
2171 * holding both task_struct::pi_lock and rq::lock.
2172 */
task_group(struct task_struct * p)2173 static inline struct task_group *task_group(struct task_struct *p)
2174 {
2175 return p->sched_task_group;
2176 }
2177
2178 /* 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)2179 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
2180 {
2181 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
2182 struct task_group *tg = task_group(p);
2183 #endif
2184
2185 #ifdef CONFIG_FAIR_GROUP_SCHED
2186 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
2187 p->se.cfs_rq = tg->cfs_rq[cpu];
2188 p->se.parent = tg->se[cpu];
2189 p->se.depth = tg->se[cpu] ? tg->se[cpu]->depth + 1 : 0;
2190 #endif
2191
2192 #ifdef CONFIG_RT_GROUP_SCHED
2193 /*
2194 * p->rt.rt_rq is NULL initially and it is easier to assign
2195 * root_task_group's rt_rq than switching in rt_rq_of_se()
2196 * Clobbers tg(!)
2197 */
2198 if (!rt_group_sched_enabled())
2199 tg = &root_task_group;
2200 p->rt.rt_rq = tg->rt_rq[cpu];
2201 p->rt.parent = tg->rt_se[cpu];
2202 #endif /* CONFIG_RT_GROUP_SCHED */
2203 }
2204
2205 #else /* !CONFIG_CGROUP_SCHED: */
2206
set_task_rq(struct task_struct * p,unsigned int cpu)2207 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
2208
task_group(struct task_struct * p)2209 static inline struct task_group *task_group(struct task_struct *p)
2210 {
2211 return NULL;
2212 }
2213
2214 #endif /* !CONFIG_CGROUP_SCHED */
2215
__set_task_cpu(struct task_struct * p,unsigned int cpu)2216 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
2217 {
2218 set_task_rq(p, cpu);
2219 #ifdef CONFIG_SMP
2220 /*
2221 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
2222 * successfully executed on another CPU. We must ensure that updates of
2223 * per-task data have been completed by this moment.
2224 */
2225 smp_wmb();
2226 WRITE_ONCE(task_thread_info(p)->cpu, cpu);
2227 p->wake_cpu = cpu;
2228 rseq_sched_set_ids_changed(p);
2229 #endif /* CONFIG_SMP */
2230 }
2231
2232 /*
2233 * Tunables:
2234 */
2235
2236 #define SCHED_FEAT(name, enabled) \
2237 __SCHED_FEAT_##name ,
2238
2239 enum {
2240 #include "features.h"
2241 __SCHED_FEAT_NR,
2242 };
2243
2244 #undef SCHED_FEAT
2245
2246 /*
2247 * To support run-time toggling of sched features, all the translation units
2248 * (but core.c) reference the sysctl_sched_features defined in core.c.
2249 */
2250 extern __read_mostly unsigned int sysctl_sched_features;
2251
2252 #ifdef CONFIG_JUMP_LABEL
2253
2254 #define SCHED_FEAT(name, enabled) \
2255 static __always_inline bool static_branch_##name(struct static_key *key) \
2256 { \
2257 return static_key_##enabled(key); \
2258 }
2259
2260 #include "features.h"
2261 #undef SCHED_FEAT
2262
2263 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
2264 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
2265
2266 #else /* !CONFIG_JUMP_LABEL: */
2267
2268 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
2269
2270 #endif /* !CONFIG_JUMP_LABEL */
2271
2272 extern struct static_key_false sched_numa_balancing;
2273 extern struct static_key_false sched_schedstats;
2274
global_rt_period(void)2275 static inline u64 global_rt_period(void)
2276 {
2277 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
2278 }
2279
global_rt_runtime(void)2280 static inline u64 global_rt_runtime(void)
2281 {
2282 if (sysctl_sched_rt_runtime < 0)
2283 return RUNTIME_INF;
2284
2285 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
2286 }
2287
2288 /*
2289 * Is p the current execution context?
2290 */
task_current(struct rq * rq,struct task_struct * p)2291 static inline int task_current(struct rq *rq, struct task_struct *p)
2292 {
2293 return rq->curr == p;
2294 }
2295
2296 /*
2297 * Is p the current scheduling context?
2298 *
2299 * Note that it might be the current execution context at the same time if
2300 * rq->curr == rq->donor == p.
2301 */
task_current_donor(struct rq * rq,struct task_struct * p)2302 static inline int task_current_donor(struct rq *rq, struct task_struct *p)
2303 {
2304 return rq->donor == p;
2305 }
2306
task_is_blocked(struct task_struct * p)2307 static inline bool task_is_blocked(struct task_struct *p)
2308 {
2309 if (!sched_proxy_exec())
2310 return false;
2311
2312 return !!p->blocked_on;
2313 }
2314
task_on_cpu(struct rq * rq,struct task_struct * p)2315 static inline int task_on_cpu(struct rq *rq, struct task_struct *p)
2316 {
2317 return p->on_cpu;
2318 }
2319
task_on_rq_queued(struct task_struct * p)2320 static inline int task_on_rq_queued(struct task_struct *p)
2321 {
2322 return READ_ONCE(p->on_rq) == TASK_ON_RQ_QUEUED;
2323 }
2324
task_on_rq_migrating(struct task_struct * p)2325 static inline int task_on_rq_migrating(struct task_struct *p)
2326 {
2327 return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
2328 }
2329
2330 /* Wake flags. The first three directly map to some SD flag value */
2331 #define WF_EXEC 0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */
2332 #define WF_FORK 0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */
2333 #define WF_TTWU 0x08 /* Wakeup; maps to SD_BALANCE_WAKE */
2334
2335 #define WF_SYNC 0x10 /* Waker goes to sleep after wakeup */
2336 #define WF_MIGRATED 0x20 /* Internal use, task got migrated */
2337 #define WF_CURRENT_CPU 0x40 /* Prefer to move the wakee to the current CPU. */
2338 #define WF_RQ_SELECTED 0x80 /* ->select_task_rq() was called */
2339
2340 static_assert(WF_EXEC == SD_BALANCE_EXEC);
2341 static_assert(WF_FORK == SD_BALANCE_FORK);
2342 static_assert(WF_TTWU == SD_BALANCE_WAKE);
2343
2344 /*
2345 * To aid in avoiding the subversion of "niceness" due to uneven distribution
2346 * of tasks with abnormal "nice" values across CPUs the contribution that
2347 * each task makes to its run queue's load is weighted according to its
2348 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
2349 * scaled version of the new time slice allocation that they receive on time
2350 * slice expiry etc.
2351 */
2352
2353 #define WEIGHT_IDLEPRIO 3
2354 #define WMULT_IDLEPRIO 1431655765
2355
2356 extern const int sched_prio_to_weight[40];
2357 extern const u32 sched_prio_to_wmult[40];
2358
2359 /*
2360 * {de,en}queue flags:
2361 *
2362 * SLEEP/WAKEUP - task is no-longer/just-became runnable
2363 *
2364 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
2365 * are in a known state which allows modification. Such pairs
2366 * should preserve as much state as possible.
2367 *
2368 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
2369 * in the runqueue.
2370 *
2371 * NOCLOCK - skip the update_rq_clock() (avoids double updates)
2372 *
2373 * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE)
2374 *
2375 * DELAYED - de/re-queue a sched_delayed task
2376 *
2377 * CLASS - going to update p->sched_class; makes sched_change call the
2378 * various switch methods.
2379 *
2380 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified)
2381 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
2382 * ENQUEUE_MIGRATED - the task was migrated during wakeup
2383 * ENQUEUE_RQ_SELECTED - ->select_task_rq() was called
2384 *
2385 * XXX SAVE/RESTORE in combination with CLASS doesn't really make sense, but
2386 * SCHED_DEADLINE seems to rely on this for now.
2387 */
2388
2389 #define DEQUEUE_SLEEP 0x0001 /* Matches ENQUEUE_WAKEUP */
2390 #define DEQUEUE_SAVE 0x0002 /* Matches ENQUEUE_RESTORE */
2391 #define DEQUEUE_MOVE 0x0004 /* Matches ENQUEUE_MOVE */
2392 #define DEQUEUE_NOCLOCK 0x0008 /* Matches ENQUEUE_NOCLOCK */
2393
2394 #define DEQUEUE_MIGRATING 0x0010 /* Matches ENQUEUE_MIGRATING */
2395 #define DEQUEUE_DELAYED 0x0020 /* Matches ENQUEUE_DELAYED */
2396 #define DEQUEUE_CLASS 0x0040 /* Matches ENQUEUE_CLASS */
2397
2398 #define DEQUEUE_SPECIAL 0x00010000
2399 #define DEQUEUE_THROTTLE 0x00020000
2400
2401 #define ENQUEUE_WAKEUP 0x0001
2402 #define ENQUEUE_RESTORE 0x0002
2403 #define ENQUEUE_MOVE 0x0004
2404 #define ENQUEUE_NOCLOCK 0x0008
2405
2406 #define ENQUEUE_MIGRATING 0x0010
2407 #define ENQUEUE_DELAYED 0x0020
2408 #define ENQUEUE_CLASS 0x0040
2409
2410 #define ENQUEUE_HEAD 0x00010000
2411 #define ENQUEUE_REPLENISH 0x00020000
2412 #define ENQUEUE_MIGRATED 0x00040000
2413 #define ENQUEUE_INITIAL 0x00080000
2414 #define ENQUEUE_RQ_SELECTED 0x00100000
2415
2416 #define RETRY_TASK ((void *)-1UL)
2417
2418 struct affinity_context {
2419 const struct cpumask *new_mask;
2420 struct cpumask *user_mask;
2421 unsigned int flags;
2422 };
2423
2424 extern s64 update_curr_common(struct rq *rq);
2425
2426 struct sched_class {
2427
2428 #ifdef CONFIG_UCLAMP_TASK
2429 int uclamp_enabled;
2430 #endif
2431 /*
2432 * idle: 0
2433 * ext: 1
2434 * fair: 2
2435 * rt: 4
2436 * dl: 8
2437 * stop: 16
2438 */
2439 unsigned int queue_mask;
2440
2441 /*
2442 * move_queued_task/activate_task/enqueue_task: rq->lock
2443 * ttwu_do_activate/activate_task/enqueue_task: rq->lock
2444 * wake_up_new_task/activate_task/enqueue_task: task_rq_lock
2445 * ttwu_runnable/enqueue_task: task_rq_lock
2446 * proxy_task_current: rq->lock
2447 * sched_change_end
2448 */
2449 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
2450 /*
2451 * move_queued_task/deactivate_task/dequeue_task: rq->lock
2452 * __schedule/block_task/dequeue_task: rq->lock
2453 * proxy_task_current: rq->lock
2454 * wait_task_inactive: task_rq_lock
2455 * sched_change_begin
2456 */
2457 bool (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
2458
2459 /*
2460 * do_sched_yield: rq->lock
2461 */
2462 void (*yield_task) (struct rq *rq);
2463 /*
2464 * yield_to: rq->lock (double)
2465 */
2466 bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
2467
2468 /*
2469 * move_queued_task: rq->lock
2470 * __migrate_swap_task: rq->lock
2471 * ttwu_do_activate: rq->lock
2472 * ttwu_runnable: task_rq_lock
2473 * wake_up_new_task: task_rq_lock
2474 */
2475 void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags);
2476
2477 /*
2478 * schedule/pick_next_task/prev_balance: rq->lock
2479 */
2480 int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
2481
2482 /*
2483 * schedule/pick_next_task: rq->lock
2484 */
2485 struct task_struct *(*pick_task)(struct rq *rq, struct rq_flags *rf);
2486 /*
2487 * Optional! When implemented pick_next_task() should be equivalent to:
2488 *
2489 * next = pick_task();
2490 * if (next) {
2491 * put_prev_task(prev);
2492 * set_next_task_first(next);
2493 * }
2494 */
2495 struct task_struct *(*pick_next_task)(struct rq *rq, struct task_struct *prev,
2496 struct rq_flags *rf);
2497
2498 /*
2499 * sched_change:
2500 * __schedule: rq->lock
2501 */
2502 void (*put_prev_task)(struct rq *rq, struct task_struct *p, struct task_struct *next);
2503 void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first);
2504
2505 /*
2506 * select_task_rq: p->pi_lock
2507 * sched_exec: p->pi_lock
2508 */
2509 int (*select_task_rq)(struct task_struct *p, int task_cpu, int flags);
2510
2511 /*
2512 * set_task_cpu: p->pi_lock || rq->lock (ttwu like)
2513 */
2514 void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
2515
2516 /*
2517 * ttwu_do_activate: rq->lock
2518 * wake_up_new_task: task_rq_lock
2519 */
2520 void (*task_woken)(struct rq *this_rq, struct task_struct *task);
2521
2522 /*
2523 * do_set_cpus_allowed: task_rq_lock + sched_change
2524 */
2525 void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx);
2526
2527 /*
2528 * sched_set_rq_{on,off}line: rq->lock
2529 */
2530 void (*rq_online)(struct rq *rq);
2531 void (*rq_offline)(struct rq *rq);
2532
2533 /*
2534 * push_cpu_stop: p->pi_lock && rq->lock
2535 */
2536 struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
2537
2538 /*
2539 * hrtick: rq->lock
2540 * sched_tick: rq->lock
2541 * sched_tick_remote: rq->lock
2542 */
2543 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
2544 /*
2545 * sched_cgroup_fork: p->pi_lock
2546 */
2547 void (*task_fork)(struct task_struct *p);
2548 /*
2549 * finish_task_switch: no locks
2550 */
2551 void (*task_dead)(struct task_struct *p);
2552
2553 /*
2554 * sched_change
2555 */
2556 void (*switching_from)(struct rq *this_rq, struct task_struct *task);
2557 void (*switched_from) (struct rq *this_rq, struct task_struct *task);
2558 void (*switching_to) (struct rq *this_rq, struct task_struct *task);
2559 void (*switched_to) (struct rq *this_rq, struct task_struct *task);
2560 u64 (*get_prio) (struct rq *this_rq, struct task_struct *task);
2561 void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
2562 u64 oldprio);
2563
2564 /*
2565 * set_load_weight: task_rq_lock + sched_change
2566 * __setscheduler_parms: task_rq_lock + sched_change
2567 */
2568 void (*reweight_task)(struct rq *this_rq, struct task_struct *task,
2569 const struct load_weight *lw);
2570
2571 /*
2572 * sched_rr_get_interval: task_rq_lock
2573 */
2574 unsigned int (*get_rr_interval)(struct rq *rq,
2575 struct task_struct *task);
2576
2577 /*
2578 * task_sched_runtime: task_rq_lock
2579 */
2580 void (*update_curr)(struct rq *rq);
2581
2582 #ifdef CONFIG_FAIR_GROUP_SCHED
2583 /*
2584 * sched_change_group: task_rq_lock + sched_change
2585 */
2586 void (*task_change_group)(struct task_struct *p);
2587 #endif
2588
2589 #ifdef CONFIG_SCHED_CORE
2590 /*
2591 * pick_next_task: rq->lock
2592 * try_steal_cookie: rq->lock (double)
2593 */
2594 int (*task_is_throttled)(struct task_struct *p, int cpu);
2595 #endif
2596 };
2597
2598 /*
2599 * Does not nest; only used around sched_class::pick_task() rq-lock-breaks.
2600 */
rq_modified_clear(struct rq * rq)2601 static inline void rq_modified_clear(struct rq *rq)
2602 {
2603 rq->queue_mask = 0;
2604 }
2605
rq_modified_above(struct rq * rq,const struct sched_class * class)2606 static inline bool rq_modified_above(struct rq *rq, const struct sched_class * class)
2607 {
2608 unsigned int mask = class->queue_mask;
2609 return rq->queue_mask & ~((mask << 1) - 1);
2610 }
2611
put_prev_task(struct rq * rq,struct task_struct * prev)2612 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
2613 {
2614 WARN_ON_ONCE(rq->donor != prev);
2615 prev->sched_class->put_prev_task(rq, prev, NULL);
2616 }
2617
set_next_task(struct rq * rq,struct task_struct * next)2618 static inline void set_next_task(struct rq *rq, struct task_struct *next)
2619 {
2620 next->sched_class->set_next_task(rq, next, false);
2621 }
2622
2623 static inline void
__put_prev_set_next_dl_server(struct rq * rq,struct task_struct * prev,struct task_struct * next)2624 __put_prev_set_next_dl_server(struct rq *rq,
2625 struct task_struct *prev,
2626 struct task_struct *next)
2627 {
2628 prev->dl_server = NULL;
2629 next->dl_server = rq->dl_server;
2630 rq->dl_server = NULL;
2631 }
2632
put_prev_set_next_task(struct rq * rq,struct task_struct * prev,struct task_struct * next)2633 static inline void put_prev_set_next_task(struct rq *rq,
2634 struct task_struct *prev,
2635 struct task_struct *next)
2636 {
2637 WARN_ON_ONCE(rq->donor != prev);
2638
2639 __put_prev_set_next_dl_server(rq, prev, next);
2640
2641 if (next == prev)
2642 return;
2643
2644 prev->sched_class->put_prev_task(rq, prev, next);
2645 next->sched_class->set_next_task(rq, next, true);
2646 }
2647
2648 /*
2649 * Helper to define a sched_class instance; each one is placed in a separate
2650 * section which is ordered by the linker script:
2651 *
2652 * include/asm-generic/vmlinux.lds.h
2653 *
2654 * *CAREFUL* they are laid out in *REVERSE* order!!!
2655 *
2656 * Also enforce alignment on the instance, not the type, to guarantee layout.
2657 */
2658 #define DEFINE_SCHED_CLASS(name) \
2659 const struct sched_class name##_sched_class \
2660 __aligned(__alignof__(struct sched_class)) \
2661 __section("__" #name "_sched_class")
2662
2663 /* Defined in include/asm-generic/vmlinux.lds.h */
2664 extern struct sched_class __sched_class_highest[];
2665 extern struct sched_class __sched_class_lowest[];
2666
2667 extern const struct sched_class stop_sched_class;
2668 extern const struct sched_class dl_sched_class;
2669 extern const struct sched_class rt_sched_class;
2670 extern const struct sched_class fair_sched_class;
2671 extern const struct sched_class idle_sched_class;
2672
2673 /*
2674 * Iterate only active classes. SCX can take over all fair tasks or be
2675 * completely disabled. If the former, skip fair. If the latter, skip SCX.
2676 */
next_active_class(const struct sched_class * class)2677 static inline const struct sched_class *next_active_class(const struct sched_class *class)
2678 {
2679 class++;
2680 #ifdef CONFIG_SCHED_CLASS_EXT
2681 if (scx_switched_all() && class == &fair_sched_class)
2682 class++;
2683 if (!scx_enabled() && class == &ext_sched_class)
2684 class++;
2685 #endif
2686 return class;
2687 }
2688
2689 #define for_class_range(class, _from, _to) \
2690 for (class = (_from); class < (_to); class++)
2691
2692 #define for_each_class(class) \
2693 for_class_range(class, __sched_class_highest, __sched_class_lowest)
2694
2695 #define for_active_class_range(class, _from, _to) \
2696 for (class = (_from); class != (_to); class = next_active_class(class))
2697
2698 #define for_each_active_class(class) \
2699 for_active_class_range(class, __sched_class_highest, __sched_class_lowest)
2700
2701 #define sched_class_above(_a, _b) ((_a) < (_b))
2702
sched_stop_runnable(struct rq * rq)2703 static inline bool sched_stop_runnable(struct rq *rq)
2704 {
2705 return rq->stop && task_on_rq_queued(rq->stop);
2706 }
2707
sched_dl_runnable(struct rq * rq)2708 static inline bool sched_dl_runnable(struct rq *rq)
2709 {
2710 return rq->dl.dl_nr_running > 0;
2711 }
2712
sched_rt_runnable(struct rq * rq)2713 static inline bool sched_rt_runnable(struct rq *rq)
2714 {
2715 return rq->rt.rt_queued > 0;
2716 }
2717
sched_fair_runnable(struct rq * rq)2718 static inline bool sched_fair_runnable(struct rq *rq)
2719 {
2720 return rq->cfs.nr_queued > 0;
2721 }
2722
2723 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev,
2724 struct rq_flags *rf);
2725 extern struct task_struct *pick_task_idle(struct rq *rq, struct rq_flags *rf);
2726
2727 #define SCA_CHECK 0x01
2728 #define SCA_MIGRATE_DISABLE 0x02
2729 #define SCA_MIGRATE_ENABLE 0x04
2730 #define SCA_USER 0x08
2731
2732 extern void update_group_capacity(struct sched_domain *sd, int cpu);
2733
2734 extern void sched_balance_trigger(struct rq *rq);
2735
2736 extern int __set_cpus_allowed_ptr(struct task_struct *p, struct affinity_context *ctx);
2737 extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx);
2738
task_allowed_on_cpu(struct task_struct * p,int cpu)2739 static inline bool task_allowed_on_cpu(struct task_struct *p, int cpu)
2740 {
2741 /* When not in the task's cpumask, no point in looking further. */
2742 if (!cpumask_test_cpu(cpu, p->cpus_ptr))
2743 return false;
2744
2745 /* Can @cpu run a user thread? */
2746 if (!(p->flags & PF_KTHREAD) && !task_cpu_possible(cpu, p))
2747 return false;
2748
2749 return true;
2750 }
2751
alloc_user_cpus_ptr(int node)2752 static inline cpumask_t *alloc_user_cpus_ptr(int node)
2753 {
2754 /*
2755 * See set_cpus_allowed_force() above for the rcu_head usage.
2756 */
2757 int size = max_t(int, cpumask_size(), sizeof(struct rcu_head));
2758
2759 return kmalloc_node(size, GFP_KERNEL, node);
2760 }
2761
get_push_task(struct rq * rq)2762 static inline struct task_struct *get_push_task(struct rq *rq)
2763 {
2764 struct task_struct *p = rq->donor;
2765
2766 lockdep_assert_rq_held(rq);
2767
2768 if (rq->push_busy)
2769 return NULL;
2770
2771 if (p->nr_cpus_allowed == 1)
2772 return NULL;
2773
2774 if (p->migration_disabled)
2775 return NULL;
2776
2777 rq->push_busy = true;
2778 return get_task_struct(p);
2779 }
2780
2781 extern int push_cpu_stop(void *arg);
2782
2783 #ifdef CONFIG_CPU_IDLE
2784
idle_set_state(struct rq * rq,struct cpuidle_state * idle_state)2785 static inline void idle_set_state(struct rq *rq,
2786 struct cpuidle_state *idle_state)
2787 {
2788 rq->idle_state = idle_state;
2789 }
2790
idle_get_state(struct rq * rq)2791 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2792 {
2793 WARN_ON_ONCE(!rcu_read_lock_held());
2794
2795 return rq->idle_state;
2796 }
2797
2798 #else /* !CONFIG_CPU_IDLE: */
2799
idle_set_state(struct rq * rq,struct cpuidle_state * idle_state)2800 static inline void idle_set_state(struct rq *rq,
2801 struct cpuidle_state *idle_state)
2802 {
2803 }
2804
idle_get_state(struct rq * rq)2805 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
2806 {
2807 return NULL;
2808 }
2809
2810 #endif /* !CONFIG_CPU_IDLE */
2811
2812 extern void schedule_idle(void);
2813 asmlinkage void schedule_user(void);
2814
2815 extern void sysrq_sched_debug_show(void);
2816 extern void sched_init_granularity(void);
2817 extern void update_max_interval(void);
2818
2819 extern void init_sched_dl_class(void);
2820 extern void init_sched_rt_class(void);
2821 extern void init_sched_fair_class(void);
2822
2823 extern void resched_curr(struct rq *rq);
2824 extern void resched_curr_lazy(struct rq *rq);
2825 extern void resched_cpu(int cpu);
2826
2827 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
2828 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq);
2829
2830 extern void init_dl_entity(struct sched_dl_entity *dl_se);
2831
2832 extern void init_cfs_throttle_work(struct task_struct *p);
2833
2834 #define BW_SHIFT 20
2835 #define BW_UNIT (1 << BW_SHIFT)
2836 #define RATIO_SHIFT 8
2837 #define MAX_BW_BITS (64 - BW_SHIFT)
2838 #define MAX_BW ((1ULL << MAX_BW_BITS) - 1)
2839
2840 extern unsigned long to_ratio(u64 period, u64 runtime);
2841
2842 extern void init_entity_runnable_average(struct sched_entity *se);
2843 extern void post_init_entity_util_avg(struct task_struct *p);
2844
2845 #ifdef CONFIG_NO_HZ_FULL
2846 extern bool sched_can_stop_tick(struct rq *rq);
2847 extern int __init sched_tick_offload_init(void);
2848
2849 /*
2850 * Tick may be needed by tasks in the runqueue depending on their policy and
2851 * requirements. If tick is needed, lets send the target an IPI to kick it out of
2852 * nohz mode if necessary.
2853 */
sched_update_tick_dependency(struct rq * rq)2854 static inline void sched_update_tick_dependency(struct rq *rq)
2855 {
2856 int cpu = cpu_of(rq);
2857
2858 if (!tick_nohz_full_cpu(cpu))
2859 return;
2860
2861 if (sched_can_stop_tick(rq))
2862 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
2863 else
2864 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
2865 }
2866 #else /* !CONFIG_NO_HZ_FULL: */
sched_tick_offload_init(void)2867 static inline int sched_tick_offload_init(void) { return 0; }
sched_update_tick_dependency(struct rq * rq)2868 static inline void sched_update_tick_dependency(struct rq *rq) { }
2869 #endif /* !CONFIG_NO_HZ_FULL */
2870
add_nr_running(struct rq * rq,unsigned count)2871 static inline void add_nr_running(struct rq *rq, unsigned count)
2872 {
2873 unsigned prev_nr = rq->nr_running;
2874
2875 rq->nr_running = prev_nr + count;
2876 if (trace_sched_update_nr_running_tp_enabled()) {
2877 call_trace_sched_update_nr_running(rq, count);
2878 }
2879
2880 if (prev_nr < 2 && rq->nr_running >= 2)
2881 set_rd_overloaded(rq->rd, 1);
2882
2883 sched_update_tick_dependency(rq);
2884 }
2885
sub_nr_running(struct rq * rq,unsigned count)2886 static inline void sub_nr_running(struct rq *rq, unsigned count)
2887 {
2888 rq->nr_running -= count;
2889 if (trace_sched_update_nr_running_tp_enabled()) {
2890 call_trace_sched_update_nr_running(rq, -count);
2891 }
2892
2893 /* Check if we still need preemption */
2894 sched_update_tick_dependency(rq);
2895 }
2896
__block_task(struct rq * rq,struct task_struct * p)2897 static inline void __block_task(struct rq *rq, struct task_struct *p)
2898 {
2899 if (p->sched_contributes_to_load)
2900 rq->nr_uninterruptible++;
2901
2902 if (p->in_iowait) {
2903 atomic_inc(&rq->nr_iowait);
2904 delayacct_blkio_start();
2905 }
2906
2907 ASSERT_EXCLUSIVE_WRITER(p->on_rq);
2908
2909 /*
2910 * The moment this write goes through, ttwu() can swoop in and migrate
2911 * this task, rendering our rq->__lock ineffective.
2912 *
2913 * __schedule() try_to_wake_up()
2914 * LOCK rq->__lock LOCK p->pi_lock
2915 * pick_next_task()
2916 * pick_next_task_fair()
2917 * pick_next_entity()
2918 * dequeue_entities()
2919 * __block_task()
2920 * RELEASE p->on_rq = 0 if (p->on_rq && ...)
2921 * break;
2922 *
2923 * ACQUIRE (after ctrl-dep)
2924 *
2925 * cpu = select_task_rq();
2926 * set_task_cpu(p, cpu);
2927 * ttwu_queue()
2928 * ttwu_do_activate()
2929 * LOCK rq->__lock
2930 * activate_task()
2931 * STORE p->on_rq = 1
2932 * UNLOCK rq->__lock
2933 *
2934 * Callers must ensure to not reference @p after this -- we no longer
2935 * own it.
2936 */
2937 smp_store_release(&p->on_rq, 0);
2938 }
2939
2940 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
2941 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
2942
2943 extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags);
2944
2945 #ifdef CONFIG_PREEMPT_RT
2946 # define SCHED_NR_MIGRATE_BREAK 8
2947 #else
2948 # define SCHED_NR_MIGRATE_BREAK 32
2949 #endif
2950
2951 extern __read_mostly unsigned int sysctl_sched_nr_migrate;
2952 extern __read_mostly unsigned int sysctl_sched_migration_cost;
2953
2954 extern unsigned int sysctl_sched_base_slice;
2955
2956 extern int sysctl_resched_latency_warn_ms;
2957 extern int sysctl_resched_latency_warn_once;
2958
2959 extern unsigned int sysctl_sched_tunable_scaling;
2960
2961 extern unsigned int sysctl_numa_balancing_scan_delay;
2962 extern unsigned int sysctl_numa_balancing_scan_period_min;
2963 extern unsigned int sysctl_numa_balancing_scan_period_max;
2964 extern unsigned int sysctl_numa_balancing_scan_size;
2965 extern unsigned int sysctl_numa_balancing_hot_threshold;
2966
2967 #ifdef CONFIG_SCHED_HRTICK
2968
2969 /*
2970 * Use hrtick when:
2971 * - enabled by features
2972 * - hrtimer is actually high res
2973 */
hrtick_enabled(struct rq * rq)2974 static inline int hrtick_enabled(struct rq *rq)
2975 {
2976 if (!cpu_active(cpu_of(rq)))
2977 return 0;
2978 return hrtimer_is_hres_active(&rq->hrtick_timer);
2979 }
2980
hrtick_enabled_fair(struct rq * rq)2981 static inline int hrtick_enabled_fair(struct rq *rq)
2982 {
2983 if (!sched_feat(HRTICK))
2984 return 0;
2985 return hrtick_enabled(rq);
2986 }
2987
hrtick_enabled_dl(struct rq * rq)2988 static inline int hrtick_enabled_dl(struct rq *rq)
2989 {
2990 if (!sched_feat(HRTICK_DL))
2991 return 0;
2992 return hrtick_enabled(rq);
2993 }
2994
2995 extern void hrtick_start(struct rq *rq, u64 delay);
2996
2997 #else /* !CONFIG_SCHED_HRTICK: */
2998
hrtick_enabled_fair(struct rq * rq)2999 static inline int hrtick_enabled_fair(struct rq *rq)
3000 {
3001 return 0;
3002 }
3003
hrtick_enabled_dl(struct rq * rq)3004 static inline int hrtick_enabled_dl(struct rq *rq)
3005 {
3006 return 0;
3007 }
3008
hrtick_enabled(struct rq * rq)3009 static inline int hrtick_enabled(struct rq *rq)
3010 {
3011 return 0;
3012 }
3013
3014 #endif /* !CONFIG_SCHED_HRTICK */
3015
3016 #ifndef arch_scale_freq_tick
arch_scale_freq_tick(void)3017 static __always_inline void arch_scale_freq_tick(void) { }
3018 #endif
3019
3020 #ifndef arch_scale_freq_capacity
3021 /**
3022 * arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
3023 * @cpu: the CPU in question.
3024 *
3025 * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
3026 *
3027 * f_curr
3028 * ------ * SCHED_CAPACITY_SCALE
3029 * f_max
3030 */
3031 static __always_inline
arch_scale_freq_capacity(int cpu)3032 unsigned long arch_scale_freq_capacity(int cpu)
3033 {
3034 return SCHED_CAPACITY_SCALE;
3035 }
3036 #endif
3037
3038 /*
3039 * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to
3040 * acquire rq lock instead of rq_lock(). So at the end of these two functions
3041 * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of
3042 * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning.
3043 */
double_rq_clock_clear_update(struct rq * rq1,struct rq * rq2)3044 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2)
3045 {
3046 rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
3047 rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
3048 }
3049
3050 #define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...) \
3051 __DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__) \
3052 static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2) \
3053 { class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t; \
3054 _lock; return _t; }
3055
rq_order_less(struct rq * rq1,struct rq * rq2)3056 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2)
3057 {
3058 #ifdef CONFIG_SCHED_CORE
3059 /*
3060 * In order to not have {0,2},{1,3} turn into into an AB-BA,
3061 * order by core-id first and cpu-id second.
3062 *
3063 * Notably:
3064 *
3065 * double_rq_lock(0,3); will take core-0, core-1 lock
3066 * double_rq_lock(1,2); will take core-1, core-0 lock
3067 *
3068 * when only cpu-id is considered.
3069 */
3070 if (rq1->core->cpu < rq2->core->cpu)
3071 return true;
3072 if (rq1->core->cpu > rq2->core->cpu)
3073 return false;
3074
3075 /*
3076 * __sched_core_flip() relies on SMT having cpu-id lock order.
3077 */
3078 #endif /* CONFIG_SCHED_CORE */
3079 return rq1->cpu < rq2->cpu;
3080 }
3081
3082 extern void double_rq_lock(struct rq *rq1, struct rq *rq2);
3083
3084 #ifdef CONFIG_PREEMPTION
3085
3086 /*
3087 * fair double_lock_balance: Safely acquires both rq->locks in a fair
3088 * way at the expense of forcing extra atomic operations in all
3089 * invocations. This assures that the double_lock is acquired using the
3090 * same underlying policy as the spinlock_t on this architecture, which
3091 * reduces latency compared to the unfair variant below. However, it
3092 * also adds more overhead and therefore may reduce throughput.
3093 */
_double_lock_balance(struct rq * this_rq,struct rq * busiest)3094 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
3095 __releases(this_rq->lock)
3096 __acquires(busiest->lock)
3097 __acquires(this_rq->lock)
3098 {
3099 raw_spin_rq_unlock(this_rq);
3100 double_rq_lock(this_rq, busiest);
3101
3102 return 1;
3103 }
3104
3105 #else /* !CONFIG_PREEMPTION: */
3106 /*
3107 * Unfair double_lock_balance: Optimizes throughput at the expense of
3108 * latency by eliminating extra atomic operations when the locks are
3109 * already in proper order on entry. This favors lower CPU-ids and will
3110 * grant the double lock to lower CPUs over higher ids under contention,
3111 * regardless of entry order into the function.
3112 */
_double_lock_balance(struct rq * this_rq,struct rq * busiest)3113 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
3114 __releases(this_rq->lock)
3115 __acquires(busiest->lock)
3116 __acquires(this_rq->lock)
3117 {
3118 if (__rq_lockp(this_rq) == __rq_lockp(busiest) ||
3119 likely(raw_spin_rq_trylock(busiest))) {
3120 double_rq_clock_clear_update(this_rq, busiest);
3121 return 0;
3122 }
3123
3124 if (rq_order_less(this_rq, busiest)) {
3125 raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING);
3126 double_rq_clock_clear_update(this_rq, busiest);
3127 return 0;
3128 }
3129
3130 raw_spin_rq_unlock(this_rq);
3131 double_rq_lock(this_rq, busiest);
3132
3133 return 1;
3134 }
3135
3136 #endif /* !CONFIG_PREEMPTION */
3137
3138 /*
3139 * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
3140 */
double_lock_balance(struct rq * this_rq,struct rq * busiest)3141 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
3142 {
3143 lockdep_assert_irqs_disabled();
3144
3145 return _double_lock_balance(this_rq, busiest);
3146 }
3147
double_unlock_balance(struct rq * this_rq,struct rq * busiest)3148 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
3149 __releases(busiest->lock)
3150 {
3151 if (__rq_lockp(this_rq) != __rq_lockp(busiest))
3152 raw_spin_rq_unlock(busiest);
3153 lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_);
3154 }
3155
double_lock(spinlock_t * l1,spinlock_t * l2)3156 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
3157 {
3158 if (l1 > l2)
3159 swap(l1, l2);
3160
3161 spin_lock(l1);
3162 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3163 }
3164
double_lock_irq(spinlock_t * l1,spinlock_t * l2)3165 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
3166 {
3167 if (l1 > l2)
3168 swap(l1, l2);
3169
3170 spin_lock_irq(l1);
3171 spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3172 }
3173
double_raw_lock(raw_spinlock_t * l1,raw_spinlock_t * l2)3174 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
3175 {
3176 if (l1 > l2)
3177 swap(l1, l2);
3178
3179 raw_spin_lock(l1);
3180 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
3181 }
3182
double_raw_unlock(raw_spinlock_t * l1,raw_spinlock_t * l2)3183 static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2)
3184 {
3185 raw_spin_unlock(l1);
3186 raw_spin_unlock(l2);
3187 }
3188
3189 DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t,
3190 double_raw_lock(_T->lock, _T->lock2),
3191 double_raw_unlock(_T->lock, _T->lock2))
3192
3193 /*
3194 * double_rq_unlock - safely unlock two runqueues
3195 *
3196 * Note this does not restore interrupts like task_rq_unlock,
3197 * you need to do so manually after calling.
3198 */
double_rq_unlock(struct rq * rq1,struct rq * rq2)3199 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
3200 __releases(rq1->lock)
3201 __releases(rq2->lock)
3202 {
3203 if (__rq_lockp(rq1) != __rq_lockp(rq2))
3204 raw_spin_rq_unlock(rq2);
3205 else
3206 __release(rq2->lock);
3207 raw_spin_rq_unlock(rq1);
3208 }
3209
3210 extern void set_rq_online (struct rq *rq);
3211 extern void set_rq_offline(struct rq *rq);
3212
3213 extern bool sched_smp_initialized;
3214
3215 DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq,
3216 double_rq_lock(_T->lock, _T->lock2),
3217 double_rq_unlock(_T->lock, _T->lock2))
3218
3219 extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq);
3220 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
3221 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
3222
3223 extern bool sched_debug_verbose;
3224
3225 extern void print_cfs_stats(struct seq_file *m, int cpu);
3226 extern void print_rt_stats(struct seq_file *m, int cpu);
3227 extern void print_dl_stats(struct seq_file *m, int cpu);
3228 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
3229 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
3230 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
3231
3232 extern void resched_latency_warn(int cpu, u64 latency);
3233
3234 #ifdef CONFIG_NUMA_BALANCING
3235 extern void show_numa_stats(struct task_struct *p, struct seq_file *m);
3236 extern void
3237 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
3238 unsigned long tpf, unsigned long gsf, unsigned long gpf);
3239 #endif /* CONFIG_NUMA_BALANCING */
3240
3241 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
3242 extern void init_rt_rq(struct rt_rq *rt_rq);
3243 extern void init_dl_rq(struct dl_rq *dl_rq);
3244
3245 extern void cfs_bandwidth_usage_inc(void);
3246 extern void cfs_bandwidth_usage_dec(void);
3247
3248 #ifdef CONFIG_NO_HZ_COMMON
3249
3250 #define NOHZ_BALANCE_KICK_BIT 0
3251 #define NOHZ_STATS_KICK_BIT 1
3252 #define NOHZ_NEWILB_KICK_BIT 2
3253 #define NOHZ_NEXT_KICK_BIT 3
3254
3255 /* Run sched_balance_domains() */
3256 #define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT)
3257 /* Update blocked load */
3258 #define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT)
3259 /* Update blocked load when entering idle */
3260 #define NOHZ_NEWILB_KICK BIT(NOHZ_NEWILB_KICK_BIT)
3261 /* Update nohz.next_balance */
3262 #define NOHZ_NEXT_KICK BIT(NOHZ_NEXT_KICK_BIT)
3263
3264 #define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK)
3265
3266 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
3267
3268 extern void nohz_balance_exit_idle(struct rq *rq);
3269 #else /* !CONFIG_NO_HZ_COMMON: */
nohz_balance_exit_idle(struct rq * rq)3270 static inline void nohz_balance_exit_idle(struct rq *rq) { }
3271 #endif /* !CONFIG_NO_HZ_COMMON */
3272
3273 #ifdef CONFIG_NO_HZ_COMMON
3274 extern void nohz_run_idle_balance(int cpu);
3275 #else
nohz_run_idle_balance(int cpu)3276 static inline void nohz_run_idle_balance(int cpu) { }
3277 #endif
3278
3279 #include "stats.h"
3280
3281 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS)
3282
3283 extern void __sched_core_account_forceidle(struct rq *rq);
3284
sched_core_account_forceidle(struct rq * rq)3285 static inline void sched_core_account_forceidle(struct rq *rq)
3286 {
3287 if (schedstat_enabled())
3288 __sched_core_account_forceidle(rq);
3289 }
3290
3291 extern void __sched_core_tick(struct rq *rq);
3292
sched_core_tick(struct rq * rq)3293 static inline void sched_core_tick(struct rq *rq)
3294 {
3295 if (sched_core_enabled(rq) && schedstat_enabled())
3296 __sched_core_tick(rq);
3297 }
3298
3299 #else /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS): */
3300
sched_core_account_forceidle(struct rq * rq)3301 static inline void sched_core_account_forceidle(struct rq *rq) { }
3302
sched_core_tick(struct rq * rq)3303 static inline void sched_core_tick(struct rq *rq) { }
3304
3305 #endif /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS) */
3306
3307 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
3308
3309 struct irqtime {
3310 u64 total;
3311 u64 tick_delta;
3312 u64 irq_start_time;
3313 struct u64_stats_sync sync;
3314 };
3315
3316 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
3317 extern int sched_clock_irqtime;
3318
irqtime_enabled(void)3319 static inline int irqtime_enabled(void)
3320 {
3321 return sched_clock_irqtime;
3322 }
3323
3324 /*
3325 * Returns the irqtime minus the softirq time computed by ksoftirqd.
3326 * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime
3327 * and never move forward.
3328 */
irq_time_read(int cpu)3329 static inline u64 irq_time_read(int cpu)
3330 {
3331 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
3332 unsigned int seq;
3333 u64 total;
3334
3335 do {
3336 seq = __u64_stats_fetch_begin(&irqtime->sync);
3337 total = irqtime->total;
3338 } while (__u64_stats_fetch_retry(&irqtime->sync, seq));
3339
3340 return total;
3341 }
3342
3343 #else /* !CONFIG_IRQ_TIME_ACCOUNTING: */
3344
irqtime_enabled(void)3345 static inline int irqtime_enabled(void)
3346 {
3347 return 0;
3348 }
3349
3350 #endif /* !CONFIG_IRQ_TIME_ACCOUNTING */
3351
3352 #ifdef CONFIG_CPU_FREQ
3353
3354 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
3355
3356 /**
3357 * cpufreq_update_util - Take a note about CPU utilization changes.
3358 * @rq: Runqueue to carry out the update for.
3359 * @flags: Update reason flags.
3360 *
3361 * This function is called by the scheduler on the CPU whose utilization is
3362 * being updated.
3363 *
3364 * It can only be called from RCU-sched read-side critical sections.
3365 *
3366 * The way cpufreq is currently arranged requires it to evaluate the CPU
3367 * performance state (frequency/voltage) on a regular basis to prevent it from
3368 * being stuck in a completely inadequate performance level for too long.
3369 * That is not guaranteed to happen if the updates are only triggered from CFS
3370 * and DL, though, because they may not be coming in if only RT tasks are
3371 * active all the time (or there are RT tasks only).
3372 *
3373 * As a workaround for that issue, this function is called periodically by the
3374 * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
3375 * but that really is a band-aid. Going forward it should be replaced with
3376 * solutions targeted more specifically at RT tasks.
3377 */
cpufreq_update_util(struct rq * rq,unsigned int flags)3378 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
3379 {
3380 struct update_util_data *data;
3381
3382 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
3383 cpu_of(rq)));
3384 if (data)
3385 data->func(data, rq_clock(rq), flags);
3386 }
3387 #else /* !CONFIG_CPU_FREQ: */
cpufreq_update_util(struct rq * rq,unsigned int flags)3388 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) { }
3389 #endif /* !CONFIG_CPU_FREQ */
3390
3391 #ifdef arch_scale_freq_capacity
3392 # ifndef arch_scale_freq_invariant
3393 # define arch_scale_freq_invariant() true
3394 # endif
3395 #else
3396 # define arch_scale_freq_invariant() false
3397 #endif
3398
3399 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
3400 unsigned long *min,
3401 unsigned long *max);
3402
3403 unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual,
3404 unsigned long min,
3405 unsigned long max);
3406
3407
3408 /*
3409 * Verify the fitness of task @p to run on @cpu taking into account the
3410 * CPU original capacity and the runtime/deadline ratio of the task.
3411 *
3412 * The function will return true if the original capacity of @cpu is
3413 * greater than or equal to task's deadline density right shifted by
3414 * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise.
3415 */
dl_task_fits_capacity(struct task_struct * p,int cpu)3416 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
3417 {
3418 unsigned long cap = arch_scale_cpu_capacity(cpu);
3419
3420 return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT);
3421 }
3422
cpu_bw_dl(struct rq * rq)3423 static inline unsigned long cpu_bw_dl(struct rq *rq)
3424 {
3425 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
3426 }
3427
cpu_util_dl(struct rq * rq)3428 static inline unsigned long cpu_util_dl(struct rq *rq)
3429 {
3430 return READ_ONCE(rq->avg_dl.util_avg);
3431 }
3432
3433
3434 extern unsigned long cpu_util_cfs(int cpu);
3435 extern unsigned long cpu_util_cfs_boost(int cpu);
3436
cpu_util_rt(struct rq * rq)3437 static inline unsigned long cpu_util_rt(struct rq *rq)
3438 {
3439 return READ_ONCE(rq->avg_rt.util_avg);
3440 }
3441
3442 #ifdef CONFIG_UCLAMP_TASK
3443
3444 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
3445
3446 /*
3447 * When uclamp is compiled in, the aggregation at rq level is 'turned off'
3448 * by default in the fast path and only gets turned on once userspace performs
3449 * an operation that requires it.
3450 *
3451 * Returns true if userspace opted-in to use uclamp and aggregation at rq level
3452 * hence is active.
3453 */
uclamp_is_used(void)3454 static inline bool uclamp_is_used(void)
3455 {
3456 return static_branch_likely(&sched_uclamp_used);
3457 }
3458
3459 /*
3460 * Enabling static branches would get the cpus_read_lock(),
3461 * check whether uclamp_is_used before enable it to avoid always
3462 * calling cpus_read_lock(). Because we never disable this
3463 * static key once enable it.
3464 */
sched_uclamp_enable(void)3465 static inline void sched_uclamp_enable(void)
3466 {
3467 if (!uclamp_is_used())
3468 static_branch_enable(&sched_uclamp_used);
3469 }
3470
uclamp_rq_get(struct rq * rq,enum uclamp_id clamp_id)3471 static inline unsigned long uclamp_rq_get(struct rq *rq,
3472 enum uclamp_id clamp_id)
3473 {
3474 return READ_ONCE(rq->uclamp[clamp_id].value);
3475 }
3476
uclamp_rq_set(struct rq * rq,enum uclamp_id clamp_id,unsigned int value)3477 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id,
3478 unsigned int value)
3479 {
3480 WRITE_ONCE(rq->uclamp[clamp_id].value, value);
3481 }
3482
uclamp_rq_is_idle(struct rq * rq)3483 static inline bool uclamp_rq_is_idle(struct rq *rq)
3484 {
3485 return rq->uclamp_flags & UCLAMP_FLAG_IDLE;
3486 }
3487
3488 /* Is the rq being capped/throttled by uclamp_max? */
uclamp_rq_is_capped(struct rq * rq)3489 static inline bool uclamp_rq_is_capped(struct rq *rq)
3490 {
3491 unsigned long rq_util;
3492 unsigned long max_util;
3493
3494 if (!uclamp_is_used())
3495 return false;
3496
3497 rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq);
3498 max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
3499
3500 return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util;
3501 }
3502
3503 #define for_each_clamp_id(clamp_id) \
3504 for ((clamp_id) = 0; (clamp_id) < UCLAMP_CNT; (clamp_id)++)
3505
3506 extern unsigned int sysctl_sched_uclamp_util_min_rt_default;
3507
3508
uclamp_none(enum uclamp_id clamp_id)3509 static inline unsigned int uclamp_none(enum uclamp_id clamp_id)
3510 {
3511 if (clamp_id == UCLAMP_MIN)
3512 return 0;
3513 return SCHED_CAPACITY_SCALE;
3514 }
3515
3516 /* Integer rounded range for each bucket */
3517 #define UCLAMP_BUCKET_DELTA DIV_ROUND_CLOSEST(SCHED_CAPACITY_SCALE, UCLAMP_BUCKETS)
3518
uclamp_bucket_id(unsigned int clamp_value)3519 static inline unsigned int uclamp_bucket_id(unsigned int clamp_value)
3520 {
3521 return min_t(unsigned int, clamp_value / UCLAMP_BUCKET_DELTA, UCLAMP_BUCKETS - 1);
3522 }
3523
3524 static inline void
uclamp_se_set(struct uclamp_se * uc_se,unsigned int value,bool user_defined)3525 uclamp_se_set(struct uclamp_se *uc_se, unsigned int value, bool user_defined)
3526 {
3527 uc_se->value = value;
3528 uc_se->bucket_id = uclamp_bucket_id(value);
3529 uc_se->user_defined = user_defined;
3530 }
3531
3532 #else /* !CONFIG_UCLAMP_TASK: */
3533
3534 static inline unsigned long
uclamp_eff_value(struct task_struct * p,enum uclamp_id clamp_id)3535 uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id)
3536 {
3537 if (clamp_id == UCLAMP_MIN)
3538 return 0;
3539
3540 return SCHED_CAPACITY_SCALE;
3541 }
3542
uclamp_rq_is_capped(struct rq * rq)3543 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; }
3544
uclamp_is_used(void)3545 static inline bool uclamp_is_used(void)
3546 {
3547 return false;
3548 }
3549
sched_uclamp_enable(void)3550 static inline void sched_uclamp_enable(void) {}
3551
3552 static inline unsigned long
uclamp_rq_get(struct rq * rq,enum uclamp_id clamp_id)3553 uclamp_rq_get(struct rq *rq, enum uclamp_id clamp_id)
3554 {
3555 if (clamp_id == UCLAMP_MIN)
3556 return 0;
3557
3558 return SCHED_CAPACITY_SCALE;
3559 }
3560
3561 static inline void
uclamp_rq_set(struct rq * rq,enum uclamp_id clamp_id,unsigned int value)3562 uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, unsigned int value)
3563 {
3564 }
3565
uclamp_rq_is_idle(struct rq * rq)3566 static inline bool uclamp_rq_is_idle(struct rq *rq)
3567 {
3568 return false;
3569 }
3570
3571 #endif /* !CONFIG_UCLAMP_TASK */
3572
3573 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
3574
cpu_util_irq(struct rq * rq)3575 static inline unsigned long cpu_util_irq(struct rq *rq)
3576 {
3577 return READ_ONCE(rq->avg_irq.util_avg);
3578 }
3579
3580 static inline
scale_irq_capacity(unsigned long util,unsigned long irq,unsigned long max)3581 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3582 {
3583 util *= (max - irq);
3584 util /= max;
3585
3586 return util;
3587
3588 }
3589
3590 #else /* !CONFIG_HAVE_SCHED_AVG_IRQ: */
3591
cpu_util_irq(struct rq * rq)3592 static inline unsigned long cpu_util_irq(struct rq *rq)
3593 {
3594 return 0;
3595 }
3596
3597 static inline
scale_irq_capacity(unsigned long util,unsigned long irq,unsigned long max)3598 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
3599 {
3600 return util;
3601 }
3602
3603 #endif /* !CONFIG_HAVE_SCHED_AVG_IRQ */
3604
3605 extern void __setparam_fair(struct task_struct *p, const struct sched_attr *attr);
3606
3607 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
3608
3609 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
3610
3611 DECLARE_STATIC_KEY_FALSE(sched_energy_present);
3612
sched_energy_enabled(void)3613 static inline bool sched_energy_enabled(void)
3614 {
3615 return static_branch_unlikely(&sched_energy_present);
3616 }
3617
3618 #else /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL): */
3619
3620 #define perf_domain_span(pd) NULL
3621
sched_energy_enabled(void)3622 static inline bool sched_energy_enabled(void) { return false; }
3623
3624 #endif /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
3625
3626 #ifdef CONFIG_MEMBARRIER
3627
3628 /*
3629 * The scheduler provides memory barriers required by membarrier between:
3630 * - prior user-space memory accesses and store to rq->membarrier_state,
3631 * - store to rq->membarrier_state and following user-space memory accesses.
3632 * In the same way it provides those guarantees around store to rq->curr.
3633 */
membarrier_switch_mm(struct rq * rq,struct mm_struct * prev_mm,struct mm_struct * next_mm)3634 static inline void membarrier_switch_mm(struct rq *rq,
3635 struct mm_struct *prev_mm,
3636 struct mm_struct *next_mm)
3637 {
3638 int membarrier_state;
3639
3640 if (prev_mm == next_mm)
3641 return;
3642
3643 membarrier_state = atomic_read(&next_mm->membarrier_state);
3644 if (READ_ONCE(rq->membarrier_state) == membarrier_state)
3645 return;
3646
3647 WRITE_ONCE(rq->membarrier_state, membarrier_state);
3648 }
3649
3650 #else /* !CONFIG_MEMBARRIER: */
3651
membarrier_switch_mm(struct rq * rq,struct mm_struct * prev_mm,struct mm_struct * next_mm)3652 static inline void membarrier_switch_mm(struct rq *rq,
3653 struct mm_struct *prev_mm,
3654 struct mm_struct *next_mm)
3655 {
3656 }
3657
3658 #endif /* !CONFIG_MEMBARRIER */
3659
is_per_cpu_kthread(struct task_struct * p)3660 static inline bool is_per_cpu_kthread(struct task_struct *p)
3661 {
3662 if (!(p->flags & PF_KTHREAD))
3663 return false;
3664
3665 if (p->nr_cpus_allowed != 1)
3666 return false;
3667
3668 return true;
3669 }
3670
3671 extern void swake_up_all_locked(struct swait_queue_head *q);
3672 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
3673
3674 extern int try_to_wake_up(struct task_struct *tsk, unsigned int state, int wake_flags);
3675
3676 #ifdef CONFIG_PREEMPT_DYNAMIC
3677 extern int preempt_dynamic_mode;
3678 extern int sched_dynamic_mode(const char *str);
3679 extern void sched_dynamic_update(int mode);
3680 #endif
3681 extern const char *preempt_modes[];
3682
3683 #ifdef CONFIG_SCHED_MM_CID
3684
cid_on_cpu(unsigned int cid)3685 static __always_inline bool cid_on_cpu(unsigned int cid)
3686 {
3687 return cid & MM_CID_ONCPU;
3688 }
3689
cid_in_transit(unsigned int cid)3690 static __always_inline bool cid_in_transit(unsigned int cid)
3691 {
3692 return cid & MM_CID_TRANSIT;
3693 }
3694
cpu_cid_to_cid(unsigned int cid)3695 static __always_inline unsigned int cpu_cid_to_cid(unsigned int cid)
3696 {
3697 return cid & ~MM_CID_ONCPU;
3698 }
3699
cid_to_cpu_cid(unsigned int cid)3700 static __always_inline unsigned int cid_to_cpu_cid(unsigned int cid)
3701 {
3702 return cid | MM_CID_ONCPU;
3703 }
3704
cid_to_transit_cid(unsigned int cid)3705 static __always_inline unsigned int cid_to_transit_cid(unsigned int cid)
3706 {
3707 return cid | MM_CID_TRANSIT;
3708 }
3709
cid_from_transit_cid(unsigned int cid)3710 static __always_inline unsigned int cid_from_transit_cid(unsigned int cid)
3711 {
3712 return cid & ~MM_CID_TRANSIT;
3713 }
3714
cid_on_task(unsigned int cid)3715 static __always_inline bool cid_on_task(unsigned int cid)
3716 {
3717 /* True if none of the MM_CID_ONCPU, MM_CID_TRANSIT, MM_CID_UNSET bits is set */
3718 return cid < MM_CID_TRANSIT;
3719 }
3720
mm_drop_cid(struct mm_struct * mm,unsigned int cid)3721 static __always_inline void mm_drop_cid(struct mm_struct *mm, unsigned int cid)
3722 {
3723 clear_bit(cid, mm_cidmask(mm));
3724 }
3725
mm_unset_cid_on_task(struct task_struct * t)3726 static __always_inline void mm_unset_cid_on_task(struct task_struct *t)
3727 {
3728 unsigned int cid = t->mm_cid.cid;
3729
3730 t->mm_cid.cid = MM_CID_UNSET;
3731 if (cid_on_task(cid))
3732 mm_drop_cid(t->mm, cid);
3733 }
3734
mm_drop_cid_on_cpu(struct mm_struct * mm,struct mm_cid_pcpu * pcp)3735 static __always_inline void mm_drop_cid_on_cpu(struct mm_struct *mm, struct mm_cid_pcpu *pcp)
3736 {
3737 /* Clear the ONCPU bit, but do not set UNSET in the per CPU storage */
3738 pcp->cid = cpu_cid_to_cid(pcp->cid);
3739 mm_drop_cid(mm, pcp->cid);
3740 }
3741
__mm_get_cid(struct mm_struct * mm,unsigned int max_cids)3742 static inline unsigned int __mm_get_cid(struct mm_struct *mm, unsigned int max_cids)
3743 {
3744 unsigned int cid = find_first_zero_bit(mm_cidmask(mm), max_cids);
3745
3746 if (cid >= max_cids)
3747 return MM_CID_UNSET;
3748 if (test_and_set_bit(cid, mm_cidmask(mm)))
3749 return MM_CID_UNSET;
3750 return cid;
3751 }
3752
mm_get_cid(struct mm_struct * mm)3753 static inline unsigned int mm_get_cid(struct mm_struct *mm)
3754 {
3755 unsigned int cid = __mm_get_cid(mm, READ_ONCE(mm->mm_cid.max_cids));
3756
3757 while (cid == MM_CID_UNSET) {
3758 cpu_relax();
3759 cid = __mm_get_cid(mm, num_possible_cpus());
3760 }
3761 return cid;
3762 }
3763
mm_cid_converge(struct mm_struct * mm,unsigned int orig_cid,unsigned int max_cids)3764 static inline unsigned int mm_cid_converge(struct mm_struct *mm, unsigned int orig_cid,
3765 unsigned int max_cids)
3766 {
3767 unsigned int new_cid, cid = cpu_cid_to_cid(orig_cid);
3768
3769 /* Is it in the optimal CID space? */
3770 if (likely(cid < max_cids))
3771 return orig_cid;
3772
3773 /* Try to find one in the optimal space. Otherwise keep the provided. */
3774 new_cid = __mm_get_cid(mm, max_cids);
3775 if (new_cid != MM_CID_UNSET) {
3776 mm_drop_cid(mm, cid);
3777 /* Preserve the ONCPU mode of the original CID */
3778 return new_cid | (orig_cid & MM_CID_ONCPU);
3779 }
3780 return orig_cid;
3781 }
3782
mm_cid_update_task_cid(struct task_struct * t,unsigned int cid)3783 static __always_inline void mm_cid_update_task_cid(struct task_struct *t, unsigned int cid)
3784 {
3785 if (t->mm_cid.cid != cid) {
3786 t->mm_cid.cid = cid;
3787 rseq_sched_set_ids_changed(t);
3788 }
3789 }
3790
mm_cid_update_pcpu_cid(struct mm_struct * mm,unsigned int cid)3791 static __always_inline void mm_cid_update_pcpu_cid(struct mm_struct *mm, unsigned int cid)
3792 {
3793 __this_cpu_write(mm->mm_cid.pcpu->cid, cid);
3794 }
3795
mm_cid_from_cpu(struct task_struct * t,unsigned int cpu_cid)3796 static __always_inline void mm_cid_from_cpu(struct task_struct *t, unsigned int cpu_cid)
3797 {
3798 unsigned int max_cids, tcid = t->mm_cid.cid;
3799 struct mm_struct *mm = t->mm;
3800
3801 max_cids = READ_ONCE(mm->mm_cid.max_cids);
3802 /* Optimize for the common case where both have the ONCPU bit set */
3803 if (likely(cid_on_cpu(cpu_cid & tcid))) {
3804 if (likely(cpu_cid_to_cid(cpu_cid) < max_cids)) {
3805 mm_cid_update_task_cid(t, cpu_cid);
3806 return;
3807 }
3808 /* Try to converge into the optimal CID space */
3809 cpu_cid = mm_cid_converge(mm, cpu_cid, max_cids);
3810 } else {
3811 /* Hand over or drop the task owned CID */
3812 if (cid_on_task(tcid)) {
3813 if (cid_on_cpu(cpu_cid))
3814 mm_unset_cid_on_task(t);
3815 else
3816 cpu_cid = cid_to_cpu_cid(tcid);
3817 }
3818 /* Still nothing, allocate a new one */
3819 if (!cid_on_cpu(cpu_cid))
3820 cpu_cid = cid_to_cpu_cid(mm_get_cid(mm));
3821 }
3822 mm_cid_update_pcpu_cid(mm, cpu_cid);
3823 mm_cid_update_task_cid(t, cpu_cid);
3824 }
3825
mm_cid_from_task(struct task_struct * t,unsigned int cpu_cid)3826 static __always_inline void mm_cid_from_task(struct task_struct *t, unsigned int cpu_cid)
3827 {
3828 unsigned int max_cids, tcid = t->mm_cid.cid;
3829 struct mm_struct *mm = t->mm;
3830
3831 max_cids = READ_ONCE(mm->mm_cid.max_cids);
3832 /* Optimize for the common case, where both have the ONCPU bit clear */
3833 if (likely(cid_on_task(tcid | cpu_cid))) {
3834 if (likely(tcid < max_cids)) {
3835 mm_cid_update_pcpu_cid(mm, tcid);
3836 return;
3837 }
3838 /* Try to converge into the optimal CID space */
3839 tcid = mm_cid_converge(mm, tcid, max_cids);
3840 } else {
3841 /* Hand over or drop the CPU owned CID */
3842 if (cid_on_cpu(cpu_cid)) {
3843 if (cid_on_task(tcid))
3844 mm_drop_cid_on_cpu(mm, this_cpu_ptr(mm->mm_cid.pcpu));
3845 else
3846 tcid = cpu_cid_to_cid(cpu_cid);
3847 }
3848 /* Still nothing, allocate a new one */
3849 if (!cid_on_task(tcid))
3850 tcid = mm_get_cid(mm);
3851 /* Set the transition mode flag if required */
3852 tcid |= READ_ONCE(mm->mm_cid.transit);
3853 }
3854 mm_cid_update_pcpu_cid(mm, tcid);
3855 mm_cid_update_task_cid(t, tcid);
3856 }
3857
mm_cid_schedin(struct task_struct * next)3858 static __always_inline void mm_cid_schedin(struct task_struct *next)
3859 {
3860 struct mm_struct *mm = next->mm;
3861 unsigned int cpu_cid;
3862
3863 if (!next->mm_cid.active)
3864 return;
3865
3866 cpu_cid = __this_cpu_read(mm->mm_cid.pcpu->cid);
3867 if (likely(!READ_ONCE(mm->mm_cid.percpu)))
3868 mm_cid_from_task(next, cpu_cid);
3869 else
3870 mm_cid_from_cpu(next, cpu_cid);
3871 }
3872
mm_cid_schedout(struct task_struct * prev)3873 static __always_inline void mm_cid_schedout(struct task_struct *prev)
3874 {
3875 /* During mode transitions CIDs are temporary and need to be dropped */
3876 if (likely(!cid_in_transit(prev->mm_cid.cid)))
3877 return;
3878
3879 mm_drop_cid(prev->mm, cid_from_transit_cid(prev->mm_cid.cid));
3880 prev->mm_cid.cid = MM_CID_UNSET;
3881 }
3882
mm_cid_switch_to(struct task_struct * prev,struct task_struct * next)3883 static inline void mm_cid_switch_to(struct task_struct *prev, struct task_struct *next)
3884 {
3885 mm_cid_schedout(prev);
3886 mm_cid_schedin(next);
3887 }
3888
3889 #else /* !CONFIG_SCHED_MM_CID: */
mm_cid_switch_to(struct task_struct * prev,struct task_struct * next)3890 static inline void mm_cid_switch_to(struct task_struct *prev, struct task_struct *next) { }
3891 #endif /* !CONFIG_SCHED_MM_CID */
3892
3893 extern u64 avg_vruntime(struct cfs_rq *cfs_rq);
3894 extern int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se);
3895 static inline
move_queued_task_locked(struct rq * src_rq,struct rq * dst_rq,struct task_struct * task)3896 void move_queued_task_locked(struct rq *src_rq, struct rq *dst_rq, struct task_struct *task)
3897 {
3898 lockdep_assert_rq_held(src_rq);
3899 lockdep_assert_rq_held(dst_rq);
3900
3901 deactivate_task(src_rq, task, 0);
3902 set_task_cpu(task, dst_rq->cpu);
3903 activate_task(dst_rq, task, 0);
3904 }
3905
3906 static inline
task_is_pushable(struct rq * rq,struct task_struct * p,int cpu)3907 bool task_is_pushable(struct rq *rq, struct task_struct *p, int cpu)
3908 {
3909 if (!task_on_cpu(rq, p) &&
3910 cpumask_test_cpu(cpu, &p->cpus_mask))
3911 return true;
3912
3913 return false;
3914 }
3915
3916 #ifdef CONFIG_RT_MUTEXES
3917
__rt_effective_prio(struct task_struct * pi_task,int prio)3918 static inline int __rt_effective_prio(struct task_struct *pi_task, int prio)
3919 {
3920 if (pi_task)
3921 prio = min(prio, pi_task->prio);
3922
3923 return prio;
3924 }
3925
rt_effective_prio(struct task_struct * p,int prio)3926 static inline int rt_effective_prio(struct task_struct *p, int prio)
3927 {
3928 struct task_struct *pi_task = rt_mutex_get_top_task(p);
3929
3930 return __rt_effective_prio(pi_task, prio);
3931 }
3932
3933 #else /* !CONFIG_RT_MUTEXES: */
3934
rt_effective_prio(struct task_struct * p,int prio)3935 static inline int rt_effective_prio(struct task_struct *p, int prio)
3936 {
3937 return prio;
3938 }
3939
3940 #endif /* !CONFIG_RT_MUTEXES */
3941
3942 extern int __sched_setscheduler(struct task_struct *p, const struct sched_attr *attr, bool user, bool pi);
3943 extern int __sched_setaffinity(struct task_struct *p, struct affinity_context *ctx);
3944 extern const struct sched_class *__setscheduler_class(int policy, int prio);
3945 extern void set_load_weight(struct task_struct *p, bool update_load);
3946 extern void enqueue_task(struct rq *rq, struct task_struct *p, int flags);
3947 extern bool dequeue_task(struct rq *rq, struct task_struct *p, int flags);
3948
3949 extern struct balance_callback *splice_balance_callbacks(struct rq *rq);
3950 extern void balance_callbacks(struct rq *rq, struct balance_callback *head);
3951
3952 /*
3953 * The 'sched_change' pattern is the safe, easy and slow way of changing a
3954 * task's scheduling properties. It dequeues a task, such that the scheduler
3955 * is fully unaware of it; at which point its properties can be modified;
3956 * after which it is enqueued again.
3957 *
3958 * Typically this must be called while holding task_rq_lock, since most/all
3959 * properties are serialized under those locks. There is currently one
3960 * exception to this rule in sched/ext which only holds rq->lock.
3961 */
3962
3963 /*
3964 * This structure is a temporary, used to preserve/convey the queueing state
3965 * of the task between sched_change_begin() and sched_change_end(). Ensuring
3966 * the task's queueing state is idempotent across the operation.
3967 */
3968 struct sched_change_ctx {
3969 u64 prio;
3970 struct task_struct *p;
3971 int flags;
3972 bool queued;
3973 bool running;
3974 };
3975
3976 struct sched_change_ctx *sched_change_begin(struct task_struct *p, unsigned int flags);
3977 void sched_change_end(struct sched_change_ctx *ctx);
3978
3979 DEFINE_CLASS(sched_change, struct sched_change_ctx *,
3980 sched_change_end(_T),
3981 sched_change_begin(p, flags),
3982 struct task_struct *p, unsigned int flags)
3983
3984 DEFINE_CLASS_IS_UNCONDITIONAL(sched_change)
3985
3986 #include "ext.h"
3987
3988 #endif /* _KERNEL_SCHED_SCHED_H */
3989