1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_SCHED_H
3 #define _LINUX_SCHED_H
4
5 /*
6 * Define 'struct task_struct' and provide the main scheduler
7 * APIs (schedule(), wakeup variants, etc.)
8 */
9
10 #include <uapi/linux/sched.h>
11
12 #include <asm/current.h>
13
14 #include <linux/pid.h>
15 #include <linux/sem.h>
16 #include <linux/shm.h>
17 #include <linux/mutex.h>
18 #include <linux/plist.h>
19 #include <linux/hrtimer.h>
20 #include <linux/irqflags.h>
21 #include <linux/seccomp.h>
22 #include <linux/nodemask.h>
23 #include <linux/rcupdate.h>
24 #include <linux/refcount.h>
25 #include <linux/resource.h>
26 #include <linux/latencytop.h>
27 #include <linux/sched/prio.h>
28 #include <linux/sched/types.h>
29 #include <linux/signal_types.h>
30 #include <linux/syscall_user_dispatch.h>
31 #include <linux/mm_types_task.h>
32 #include <linux/task_io_accounting.h>
33 #include <linux/posix-timers.h>
34 #include <linux/rseq.h>
35 #include <linux/seqlock.h>
36 #include <linux/kcsan.h>
37 #include <linux/android_vendor.h>
38 #include <asm/kmap_size.h>
39 #include <linux/android_kabi.h>
40
41 /* task_struct member predeclarations (sorted alphabetically): */
42 struct audit_context;
43 struct backing_dev_info;
44 struct bio_list;
45 struct blk_plug;
46 struct bpf_local_storage;
47 struct bpf_run_ctx;
48 struct capture_control;
49 struct cfs_rq;
50 struct fs_struct;
51 struct futex_pi_state;
52 struct io_context;
53 struct io_uring_task;
54 struct mempolicy;
55 struct nameidata;
56 struct nsproxy;
57 struct perf_event_context;
58 struct pid_namespace;
59 struct pipe_inode_info;
60 struct rcu_node;
61 struct reclaim_state;
62 struct robust_list_head;
63 struct root_domain;
64 struct rq;
65 struct sched_attr;
66 struct sched_param;
67 struct seq_file;
68 struct sighand_struct;
69 struct signal_struct;
70 struct task_delay_info;
71 struct task_group;
72
73 /*
74 * Task state bitmask. NOTE! These bits are also
75 * encoded in fs/proc/array.c: get_task_state().
76 *
77 * We have two separate sets of flags: task->state
78 * is about runnability, while task->exit_state are
79 * about the task exiting. Confusing, but this way
80 * modifying one set can't modify the other one by
81 * mistake.
82 */
83
84 /* Used in tsk->state: */
85 #define TASK_RUNNING 0x0000
86 #define TASK_INTERRUPTIBLE 0x0001
87 #define TASK_UNINTERRUPTIBLE 0x0002
88 #define __TASK_STOPPED 0x0004
89 #define __TASK_TRACED 0x0008
90 /* Used in tsk->exit_state: */
91 #define EXIT_DEAD 0x0010
92 #define EXIT_ZOMBIE 0x0020
93 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD)
94 /* Used in tsk->state again: */
95 #define TASK_PARKED 0x0040
96 #define TASK_DEAD 0x0080
97 #define TASK_WAKEKILL 0x0100
98 #define TASK_WAKING 0x0200
99 #define TASK_NOLOAD 0x0400
100 #define TASK_NEW 0x0800
101 /* RT specific auxilliary flag to mark RT lock waiters */
102 #define TASK_RTLOCK_WAIT 0x1000
103 #define TASK_STATE_MAX 0x2000
104
105 /* Convenience macros for the sake of set_current_state: */
106 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
107 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)
108 #define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED)
109
110 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
111
112 /* Convenience macros for the sake of wake_up(): */
113 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
114
115 /* get_task_state(): */
116 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \
117 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
118 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \
119 TASK_PARKED)
120
121 #define task_is_running(task) (READ_ONCE((task)->__state) == TASK_RUNNING)
122
123 #define task_is_traced(task) ((READ_ONCE(task->__state) & __TASK_TRACED) != 0)
124
125 #define task_is_stopped(task) ((READ_ONCE(task->__state) & __TASK_STOPPED) != 0)
126
127 #define task_is_stopped_or_traced(task) ((READ_ONCE(task->__state) & (__TASK_STOPPED | __TASK_TRACED)) != 0)
128
129 /*
130 * Special states are those that do not use the normal wait-loop pattern. See
131 * the comment with set_special_state().
132 */
133 #define is_special_task_state(state) \
134 ((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | TASK_DEAD))
135
136 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
137 # define debug_normal_state_change(state_value) \
138 do { \
139 WARN_ON_ONCE(is_special_task_state(state_value)); \
140 current->task_state_change = _THIS_IP_; \
141 } while (0)
142
143 # define debug_special_state_change(state_value) \
144 do { \
145 WARN_ON_ONCE(!is_special_task_state(state_value)); \
146 current->task_state_change = _THIS_IP_; \
147 } while (0)
148
149 # define debug_rtlock_wait_set_state() \
150 do { \
151 current->saved_state_change = current->task_state_change;\
152 current->task_state_change = _THIS_IP_; \
153 } while (0)
154
155 # define debug_rtlock_wait_restore_state() \
156 do { \
157 current->task_state_change = current->saved_state_change;\
158 } while (0)
159
160 #else
161 # define debug_normal_state_change(cond) do { } while (0)
162 # define debug_special_state_change(cond) do { } while (0)
163 # define debug_rtlock_wait_set_state() do { } while (0)
164 # define debug_rtlock_wait_restore_state() do { } while (0)
165 #endif
166
167 /*
168 * set_current_state() includes a barrier so that the write of current->state
169 * is correctly serialised wrt the caller's subsequent test of whether to
170 * actually sleep:
171 *
172 * for (;;) {
173 * set_current_state(TASK_UNINTERRUPTIBLE);
174 * if (CONDITION)
175 * break;
176 *
177 * schedule();
178 * }
179 * __set_current_state(TASK_RUNNING);
180 *
181 * If the caller does not need such serialisation (because, for instance, the
182 * CONDITION test and condition change and wakeup are under the same lock) then
183 * use __set_current_state().
184 *
185 * The above is typically ordered against the wakeup, which does:
186 *
187 * CONDITION = 1;
188 * wake_up_state(p, TASK_UNINTERRUPTIBLE);
189 *
190 * where wake_up_state()/try_to_wake_up() executes a full memory barrier before
191 * accessing p->state.
192 *
193 * Wakeup will do: if (@state & p->state) p->state = TASK_RUNNING, that is,
194 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a
195 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING).
196 *
197 * However, with slightly different timing the wakeup TASK_RUNNING store can
198 * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not
199 * a problem either because that will result in one extra go around the loop
200 * and our @cond test will save the day.
201 *
202 * Also see the comments of try_to_wake_up().
203 */
204 #define __set_current_state(state_value) \
205 do { \
206 debug_normal_state_change((state_value)); \
207 WRITE_ONCE(current->__state, (state_value)); \
208 } while (0)
209
210 #define set_current_state(state_value) \
211 do { \
212 debug_normal_state_change((state_value)); \
213 smp_store_mb(current->__state, (state_value)); \
214 } while (0)
215
216 /*
217 * set_special_state() should be used for those states when the blocking task
218 * can not use the regular condition based wait-loop. In that case we must
219 * serialize against wakeups such that any possible in-flight TASK_RUNNING
220 * stores will not collide with our state change.
221 */
222 #define set_special_state(state_value) \
223 do { \
224 unsigned long flags; /* may shadow */ \
225 \
226 raw_spin_lock_irqsave(¤t->pi_lock, flags); \
227 debug_special_state_change((state_value)); \
228 WRITE_ONCE(current->__state, (state_value)); \
229 raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \
230 } while (0)
231
232 /*
233 * PREEMPT_RT specific variants for "sleeping" spin/rwlocks
234 *
235 * RT's spin/rwlock substitutions are state preserving. The state of the
236 * task when blocking on the lock is saved in task_struct::saved_state and
237 * restored after the lock has been acquired. These operations are
238 * serialized by task_struct::pi_lock against try_to_wake_up(). Any non RT
239 * lock related wakeups while the task is blocked on the lock are
240 * redirected to operate on task_struct::saved_state to ensure that these
241 * are not dropped. On restore task_struct::saved_state is set to
242 * TASK_RUNNING so any wakeup attempt redirected to saved_state will fail.
243 *
244 * The lock operation looks like this:
245 *
246 * current_save_and_set_rtlock_wait_state();
247 * for (;;) {
248 * if (try_lock())
249 * break;
250 * raw_spin_unlock_irq(&lock->wait_lock);
251 * schedule_rtlock();
252 * raw_spin_lock_irq(&lock->wait_lock);
253 * set_current_state(TASK_RTLOCK_WAIT);
254 * }
255 * current_restore_rtlock_saved_state();
256 */
257 #define current_save_and_set_rtlock_wait_state() \
258 do { \
259 lockdep_assert_irqs_disabled(); \
260 raw_spin_lock(¤t->pi_lock); \
261 current->saved_state = current->__state; \
262 debug_rtlock_wait_set_state(); \
263 WRITE_ONCE(current->__state, TASK_RTLOCK_WAIT); \
264 raw_spin_unlock(¤t->pi_lock); \
265 } while (0);
266
267 #define current_restore_rtlock_saved_state() \
268 do { \
269 lockdep_assert_irqs_disabled(); \
270 raw_spin_lock(¤t->pi_lock); \
271 debug_rtlock_wait_restore_state(); \
272 WRITE_ONCE(current->__state, current->saved_state); \
273 current->saved_state = TASK_RUNNING; \
274 raw_spin_unlock(¤t->pi_lock); \
275 } while (0);
276
277 #define get_current_state() READ_ONCE(current->__state)
278
279 /* Task command name length: */
280 #define TASK_COMM_LEN 16
281
282 extern void scheduler_tick(void);
283
284 #define MAX_SCHEDULE_TIMEOUT LONG_MAX
285
286 extern long schedule_timeout(long timeout);
287 extern long schedule_timeout_interruptible(long timeout);
288 extern long schedule_timeout_killable(long timeout);
289 extern long schedule_timeout_uninterruptible(long timeout);
290 extern long schedule_timeout_idle(long timeout);
291 asmlinkage void schedule(void);
292 extern void schedule_preempt_disabled(void);
293 asmlinkage void preempt_schedule_irq(void);
294 #ifdef CONFIG_PREEMPT_RT
295 extern void schedule_rtlock(void);
296 #endif
297
298 extern int __must_check io_schedule_prepare(void);
299 extern void io_schedule_finish(int token);
300 extern long io_schedule_timeout(long timeout);
301 extern void io_schedule(void);
302 extern struct task_struct *pick_migrate_task(struct rq *rq);
303 extern int select_fallback_rq(int cpu, struct task_struct *p);
304
305 /**
306 * struct prev_cputime - snapshot of system and user cputime
307 * @utime: time spent in user mode
308 * @stime: time spent in system mode
309 * @lock: protects the above two fields
310 *
311 * Stores previous user/system time values such that we can guarantee
312 * monotonicity.
313 */
314 struct prev_cputime {
315 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
316 u64 utime;
317 u64 stime;
318 raw_spinlock_t lock;
319 #endif
320 };
321
322 enum vtime_state {
323 /* Task is sleeping or running in a CPU with VTIME inactive: */
324 VTIME_INACTIVE = 0,
325 /* Task is idle */
326 VTIME_IDLE,
327 /* Task runs in kernelspace in a CPU with VTIME active: */
328 VTIME_SYS,
329 /* Task runs in userspace in a CPU with VTIME active: */
330 VTIME_USER,
331 /* Task runs as guests in a CPU with VTIME active: */
332 VTIME_GUEST,
333 };
334
335 struct vtime {
336 seqcount_t seqcount;
337 unsigned long long starttime;
338 enum vtime_state state;
339 unsigned int cpu;
340 u64 utime;
341 u64 stime;
342 u64 gtime;
343 };
344
345 /*
346 * Utilization clamp constraints.
347 * @UCLAMP_MIN: Minimum utilization
348 * @UCLAMP_MAX: Maximum utilization
349 * @UCLAMP_CNT: Utilization clamp constraints count
350 */
351 enum uclamp_id {
352 UCLAMP_MIN = 0,
353 UCLAMP_MAX,
354 UCLAMP_CNT
355 };
356
357 #ifdef CONFIG_SMP
358 extern struct root_domain def_root_domain;
359 extern struct mutex sched_domains_mutex;
360 #endif
361
362 struct sched_info {
363 #ifdef CONFIG_SCHED_INFO
364 /* Cumulative counters: */
365
366 /* # of times we have run on this CPU: */
367 unsigned long pcount;
368
369 /* Time spent waiting on a runqueue: */
370 unsigned long long run_delay;
371
372 /* Timestamps: */
373
374 /* When did we last run on a CPU? */
375 unsigned long long last_arrival;
376
377 /* When were we last queued to run? */
378 unsigned long long last_queued;
379
380 #endif /* CONFIG_SCHED_INFO */
381 };
382
383 /*
384 * Integer metrics need fixed point arithmetic, e.g., sched/fair
385 * has a few: load, load_avg, util_avg, freq, and capacity.
386 *
387 * We define a basic fixed point arithmetic range, and then formalize
388 * all these metrics based on that basic range.
389 */
390 # define SCHED_FIXEDPOINT_SHIFT 10
391 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT)
392
393 /* Increase resolution of cpu_capacity calculations */
394 # define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT
395 # define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT)
396
397 struct load_weight {
398 unsigned long weight;
399 u32 inv_weight;
400 };
401
402 /**
403 * struct util_est - Estimation utilization of FAIR tasks
404 * @enqueued: instantaneous estimated utilization of a task/cpu
405 * @ewma: the Exponential Weighted Moving Average (EWMA)
406 * utilization of a task
407 *
408 * Support data structure to track an Exponential Weighted Moving Average
409 * (EWMA) of a FAIR task's utilization. New samples are added to the moving
410 * average each time a task completes an activation. Sample's weight is chosen
411 * so that the EWMA will be relatively insensitive to transient changes to the
412 * task's workload.
413 *
414 * The enqueued attribute has a slightly different meaning for tasks and cpus:
415 * - task: the task's util_avg at last task dequeue time
416 * - cfs_rq: the sum of util_est.enqueued for each RUNNABLE task on that CPU
417 * Thus, the util_est.enqueued of a task represents the contribution on the
418 * estimated utilization of the CPU where that task is currently enqueued.
419 *
420 * Only for tasks we track a moving average of the past instantaneous
421 * estimated utilization. This allows to absorb sporadic drops in utilization
422 * of an otherwise almost periodic task.
423 *
424 * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg
425 * updates. When a task is dequeued, its util_est should not be updated if its
426 * util_avg has not been updated in the meantime.
427 * This information is mapped into the MSB bit of util_est.enqueued at dequeue
428 * time. Since max value of util_est.enqueued for a task is 1024 (PELT util_avg
429 * for a task) it is safe to use MSB.
430 */
431 struct util_est {
432 unsigned int enqueued;
433 unsigned int ewma;
434 #define UTIL_EST_WEIGHT_SHIFT 2
435 #define UTIL_AVG_UNCHANGED 0x80000000
436 } __attribute__((__aligned__(sizeof(u64))));
437
438 /*
439 * The load/runnable/util_avg accumulates an infinite geometric series
440 * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c).
441 *
442 * [load_avg definition]
443 *
444 * load_avg = runnable% * scale_load_down(load)
445 *
446 * [runnable_avg definition]
447 *
448 * runnable_avg = runnable% * SCHED_CAPACITY_SCALE
449 *
450 * [util_avg definition]
451 *
452 * util_avg = running% * SCHED_CAPACITY_SCALE
453 *
454 * where runnable% is the time ratio that a sched_entity is runnable and
455 * running% the time ratio that a sched_entity is running.
456 *
457 * For cfs_rq, they are the aggregated values of all runnable and blocked
458 * sched_entities.
459 *
460 * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU
461 * capacity scaling. The scaling is done through the rq_clock_pelt that is used
462 * for computing those signals (see update_rq_clock_pelt())
463 *
464 * N.B., the above ratios (runnable% and running%) themselves are in the
465 * range of [0, 1]. To do fixed point arithmetics, we therefore scale them
466 * to as large a range as necessary. This is for example reflected by
467 * util_avg's SCHED_CAPACITY_SCALE.
468 *
469 * [Overflow issue]
470 *
471 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
472 * with the highest load (=88761), always runnable on a single cfs_rq,
473 * and should not overflow as the number already hits PID_MAX_LIMIT.
474 *
475 * For all other cases (including 32-bit kernels), struct load_weight's
476 * weight will overflow first before we do, because:
477 *
478 * Max(load_avg) <= Max(load.weight)
479 *
480 * Then it is the load_weight's responsibility to consider overflow
481 * issues.
482 */
483 struct sched_avg {
484 u64 last_update_time;
485 u64 load_sum;
486 u64 runnable_sum;
487 u32 util_sum;
488 u32 period_contrib;
489 unsigned long load_avg;
490 unsigned long runnable_avg;
491 unsigned long util_avg;
492 struct util_est util_est;
493 } ____cacheline_aligned;
494
495 struct sched_statistics {
496 #ifdef CONFIG_SCHEDSTATS
497 u64 wait_start;
498 u64 wait_max;
499 u64 wait_count;
500 u64 wait_sum;
501 u64 iowait_count;
502 u64 iowait_sum;
503
504 u64 sleep_start;
505 u64 sleep_max;
506 s64 sum_sleep_runtime;
507
508 u64 block_start;
509 u64 block_max;
510 u64 exec_max;
511 u64 slice_max;
512
513 u64 nr_migrations_cold;
514 u64 nr_failed_migrations_affine;
515 u64 nr_failed_migrations_running;
516 u64 nr_failed_migrations_hot;
517 u64 nr_forced_migrations;
518
519 u64 nr_wakeups;
520 u64 nr_wakeups_sync;
521 u64 nr_wakeups_migrate;
522 u64 nr_wakeups_local;
523 u64 nr_wakeups_remote;
524 u64 nr_wakeups_affine;
525 u64 nr_wakeups_affine_attempts;
526 u64 nr_wakeups_passive;
527 u64 nr_wakeups_idle;
528 #endif
529 };
530
531 struct sched_entity {
532 /* For load-balancing: */
533 struct load_weight load;
534 struct rb_node run_node;
535 struct list_head group_node;
536 unsigned int on_rq;
537
538 u64 exec_start;
539 u64 sum_exec_runtime;
540 u64 vruntime;
541 u64 prev_sum_exec_runtime;
542
543 u64 nr_migrations;
544
545 struct sched_statistics statistics;
546
547 #ifdef CONFIG_FAIR_GROUP_SCHED
548 int depth;
549 struct sched_entity *parent;
550 /* rq on which this entity is (to be) queued: */
551 struct cfs_rq *cfs_rq;
552 /* rq "owned" by this entity/group: */
553 struct cfs_rq *my_q;
554 /* cached value of my_q->h_nr_running */
555 unsigned long runnable_weight;
556 #endif
557
558 #ifdef CONFIG_SMP
559 /*
560 * Per entity load average tracking.
561 *
562 * Put into separate cache line so it does not
563 * collide with read-mostly values above.
564 */
565 struct sched_avg avg;
566 #endif
567
568 ANDROID_KABI_RESERVE(1);
569 ANDROID_KABI_RESERVE(2);
570 ANDROID_KABI_RESERVE(3);
571 ANDROID_KABI_RESERVE(4);
572 };
573
574 struct sched_rt_entity {
575 struct list_head run_list;
576 unsigned long timeout;
577 unsigned long watchdog_stamp;
578 unsigned int time_slice;
579 unsigned short on_rq;
580 unsigned short on_list;
581
582 struct sched_rt_entity *back;
583 #ifdef CONFIG_RT_GROUP_SCHED
584 struct sched_rt_entity *parent;
585 /* rq on which this entity is (to be) queued: */
586 struct rt_rq *rt_rq;
587 /* rq "owned" by this entity/group: */
588 struct rt_rq *my_q;
589 #endif
590
591 ANDROID_KABI_RESERVE(1);
592 ANDROID_KABI_RESERVE(2);
593 ANDROID_KABI_RESERVE(3);
594 ANDROID_KABI_RESERVE(4);
595 } __randomize_layout;
596
597 struct sched_dl_entity {
598 struct rb_node rb_node;
599
600 /*
601 * Original scheduling parameters. Copied here from sched_attr
602 * during sched_setattr(), they will remain the same until
603 * the next sched_setattr().
604 */
605 u64 dl_runtime; /* Maximum runtime for each instance */
606 u64 dl_deadline; /* Relative deadline of each instance */
607 u64 dl_period; /* Separation of two instances (period) */
608 u64 dl_bw; /* dl_runtime / dl_period */
609 u64 dl_density; /* dl_runtime / dl_deadline */
610
611 /*
612 * Actual scheduling parameters. Initialized with the values above,
613 * they are continuously updated during task execution. Note that
614 * the remaining runtime could be < 0 in case we are in overrun.
615 */
616 s64 runtime; /* Remaining runtime for this instance */
617 u64 deadline; /* Absolute deadline for this instance */
618 unsigned int flags; /* Specifying the scheduler behaviour */
619
620 /*
621 * Some bool flags:
622 *
623 * @dl_throttled tells if we exhausted the runtime. If so, the
624 * task has to wait for a replenishment to be performed at the
625 * next firing of dl_timer.
626 *
627 * @dl_boosted tells if we are boosted due to DI. If so we are
628 * outside bandwidth enforcement mechanism (but only until we
629 * exit the critical section);
630 *
631 * @dl_yielded tells if task gave up the CPU before consuming
632 * all its available runtime during the last job.
633 *
634 * @dl_non_contending tells if the task is inactive while still
635 * contributing to the active utilization. In other words, it
636 * indicates if the inactive timer has been armed and its handler
637 * has not been executed yet. This flag is useful to avoid race
638 * conditions between the inactive timer handler and the wakeup
639 * code.
640 *
641 * @dl_overrun tells if the task asked to be informed about runtime
642 * overruns.
643 */
644 unsigned int dl_throttled : 1;
645 unsigned int dl_yielded : 1;
646 unsigned int dl_non_contending : 1;
647 unsigned int dl_overrun : 1;
648
649 /*
650 * Bandwidth enforcement timer. Each -deadline task has its
651 * own bandwidth to be enforced, thus we need one timer per task.
652 */
653 struct hrtimer dl_timer;
654
655 /*
656 * Inactive timer, responsible for decreasing the active utilization
657 * at the "0-lag time". When a -deadline task blocks, it contributes
658 * to GRUB's active utilization until the "0-lag time", hence a
659 * timer is needed to decrease the active utilization at the correct
660 * time.
661 */
662 struct hrtimer inactive_timer;
663
664 #ifdef CONFIG_RT_MUTEXES
665 /*
666 * Priority Inheritance. When a DEADLINE scheduling entity is boosted
667 * pi_se points to the donor, otherwise points to the dl_se it belongs
668 * to (the original one/itself).
669 */
670 struct sched_dl_entity *pi_se;
671 #endif
672 };
673
674 #ifdef CONFIG_UCLAMP_TASK
675 /* Number of utilization clamp buckets (shorter alias) */
676 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT
677
678 /*
679 * Utilization clamp for a scheduling entity
680 * @value: clamp value "assigned" to a se
681 * @bucket_id: bucket index corresponding to the "assigned" value
682 * @active: the se is currently refcounted in a rq's bucket
683 * @user_defined: the requested clamp value comes from user-space
684 *
685 * The bucket_id is the index of the clamp bucket matching the clamp value
686 * which is pre-computed and stored to avoid expensive integer divisions from
687 * the fast path.
688 *
689 * The active bit is set whenever a task has got an "effective" value assigned,
690 * which can be different from the clamp value "requested" from user-space.
691 * This allows to know a task is refcounted in the rq's bucket corresponding
692 * to the "effective" bucket_id.
693 *
694 * The user_defined bit is set whenever a task has got a task-specific clamp
695 * value requested from userspace, i.e. the system defaults apply to this task
696 * just as a restriction. This allows to relax default clamps when a less
697 * restrictive task-specific value has been requested, thus allowing to
698 * implement a "nice" semantic. For example, a task running with a 20%
699 * default boost can still drop its own boosting to 0%.
700 */
701 struct uclamp_se {
702 unsigned int value : bits_per(SCHED_CAPACITY_SCALE);
703 unsigned int bucket_id : bits_per(UCLAMP_BUCKETS);
704 unsigned int active : 1;
705 unsigned int user_defined : 1;
706 };
707 #endif /* CONFIG_UCLAMP_TASK */
708
709 union rcu_special {
710 struct {
711 u8 blocked;
712 u8 need_qs;
713 u8 exp_hint; /* Hint for performance. */
714 u8 need_mb; /* Readers need smp_mb(). */
715 } b; /* Bits. */
716 u32 s; /* Set of bits. */
717 };
718
719 enum perf_event_task_context {
720 perf_invalid_context = -1,
721 perf_hw_context = 0,
722 perf_sw_context,
723 perf_nr_task_contexts,
724 };
725
726 struct wake_q_node {
727 struct wake_q_node *next;
728 };
729
730 struct kmap_ctrl {
731 #ifdef CONFIG_KMAP_LOCAL
732 int idx;
733 pte_t pteval[KM_MAX_IDX];
734 #endif
735 };
736
737 struct task_struct {
738 #ifdef CONFIG_THREAD_INFO_IN_TASK
739 /*
740 * For reasons of header soup (see current_thread_info()), this
741 * must be the first element of task_struct.
742 */
743 struct thread_info thread_info;
744 #endif
745 unsigned int __state;
746
747 #ifdef CONFIG_PREEMPT_RT
748 /* saved state for "spinlock sleepers" */
749 unsigned int saved_state;
750 #endif
751
752 /*
753 * This begins the randomizable portion of task_struct. Only
754 * scheduling-critical items should be added above here.
755 */
756 randomized_struct_fields_start
757
758 void *stack;
759 refcount_t usage;
760 /* Per task flags (PF_*), defined further below: */
761 unsigned int flags;
762 unsigned int ptrace;
763
764 #ifdef CONFIG_SMP
765 int on_cpu;
766 struct __call_single_node wake_entry;
767 #ifdef CONFIG_THREAD_INFO_IN_TASK
768 /* Current CPU: */
769 unsigned int cpu;
770 #endif
771 unsigned int wakee_flips;
772 unsigned long wakee_flip_decay_ts;
773 struct task_struct *last_wakee;
774
775 /*
776 * recent_used_cpu is initially set as the last CPU used by a task
777 * that wakes affine another task. Waker/wakee relationships can
778 * push tasks around a CPU where each wakeup moves to the next one.
779 * Tracking a recently used CPU allows a quick search for a recently
780 * used CPU that may be idle.
781 */
782 int recent_used_cpu;
783 int wake_cpu;
784 #endif
785 int on_rq;
786
787 int prio;
788 int static_prio;
789 int normal_prio;
790 unsigned int rt_priority;
791
792 const struct sched_class *sched_class;
793 struct sched_entity se;
794 struct sched_rt_entity rt;
795 struct sched_dl_entity dl;
796
797 #ifdef CONFIG_SCHED_CORE
798 struct rb_node core_node;
799 unsigned long core_cookie;
800 unsigned int core_occupation;
801 #endif
802
803 #ifdef CONFIG_CGROUP_SCHED
804 struct task_group *sched_task_group;
805 #endif
806
807 #ifdef CONFIG_UCLAMP_TASK
808 /*
809 * Clamp values requested for a scheduling entity.
810 * Must be updated with task_rq_lock() held.
811 */
812 struct uclamp_se uclamp_req[UCLAMP_CNT];
813 /*
814 * Effective clamp values used for a scheduling entity.
815 * Must be updated with task_rq_lock() held.
816 */
817 struct uclamp_se uclamp[UCLAMP_CNT];
818 #endif
819
820 #ifdef CONFIG_PREEMPT_NOTIFIERS
821 /* List of struct preempt_notifier: */
822 struct hlist_head preempt_notifiers;
823 #endif
824
825 #ifdef CONFIG_BLK_DEV_IO_TRACE
826 unsigned int btrace_seq;
827 #endif
828
829 unsigned int policy;
830 int nr_cpus_allowed;
831 const cpumask_t *cpus_ptr;
832 cpumask_t *user_cpus_ptr;
833 cpumask_t cpus_mask;
834 void *migration_pending;
835 #ifdef CONFIG_SMP
836 unsigned short migration_disabled;
837 #endif
838 unsigned short migration_flags;
839
840 #ifdef CONFIG_PREEMPT_RCU
841 int rcu_read_lock_nesting;
842 union rcu_special rcu_read_unlock_special;
843 struct list_head rcu_node_entry;
844 struct rcu_node *rcu_blocked_node;
845 #endif /* #ifdef CONFIG_PREEMPT_RCU */
846
847 #ifdef CONFIG_TASKS_RCU
848 unsigned long rcu_tasks_nvcsw;
849 u8 rcu_tasks_holdout;
850 u8 rcu_tasks_idx;
851 int rcu_tasks_idle_cpu;
852 struct list_head rcu_tasks_holdout_list;
853 #endif /* #ifdef CONFIG_TASKS_RCU */
854
855 #ifdef CONFIG_TASKS_TRACE_RCU
856 int trc_reader_nesting;
857 int trc_ipi_to_cpu;
858 union rcu_special trc_reader_special;
859 bool trc_reader_checked;
860 struct list_head trc_holdout_list;
861 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */
862
863 struct sched_info sched_info;
864
865 struct list_head tasks;
866 #ifdef CONFIG_SMP
867 struct plist_node pushable_tasks;
868 struct rb_node pushable_dl_tasks;
869 #endif
870
871 struct mm_struct *mm;
872 struct mm_struct *active_mm;
873
874 /* Per-thread vma caching: */
875 struct vmacache vmacache;
876
877 #ifdef SPLIT_RSS_COUNTING
878 struct task_rss_stat rss_stat;
879 #endif
880 int exit_state;
881 int exit_code;
882 int exit_signal;
883 /* The signal sent when the parent dies: */
884 int pdeath_signal;
885 /* JOBCTL_*, siglock protected: */
886 unsigned long jobctl;
887
888 /* Used for emulating ABI behavior of previous Linux versions: */
889 unsigned int personality;
890
891 /* Scheduler bits, serialized by scheduler locks: */
892 unsigned sched_reset_on_fork:1;
893 unsigned sched_contributes_to_load:1;
894 unsigned sched_migrated:1;
895 #ifdef CONFIG_PSI
896 unsigned sched_psi_wake_requeue:1;
897 #endif
898
899 /* Force alignment to the next boundary: */
900 unsigned :0;
901
902 /* Unserialized, strictly 'current' */
903
904 /*
905 * This field must not be in the scheduler word above due to wakelist
906 * queueing no longer being serialized by p->on_cpu. However:
907 *
908 * p->XXX = X; ttwu()
909 * schedule() if (p->on_rq && ..) // false
910 * smp_mb__after_spinlock(); if (smp_load_acquire(&p->on_cpu) && //true
911 * deactivate_task() ttwu_queue_wakelist())
912 * p->on_rq = 0; p->sched_remote_wakeup = Y;
913 *
914 * guarantees all stores of 'current' are visible before
915 * ->sched_remote_wakeup gets used, so it can be in this word.
916 */
917 unsigned sched_remote_wakeup:1;
918
919 /* Bit to tell LSMs we're in execve(): */
920 unsigned in_execve:1;
921 unsigned in_iowait:1;
922 #ifndef TIF_RESTORE_SIGMASK
923 unsigned restore_sigmask:1;
924 #endif
925 #ifdef CONFIG_MEMCG
926 unsigned in_user_fault:1;
927 #endif
928 #ifdef CONFIG_LRU_GEN
929 /* whether the LRU algorithm may apply to this access */
930 unsigned in_lru_fault:1;
931 #endif
932 #ifdef CONFIG_COMPAT_BRK
933 unsigned brk_randomized:1;
934 #endif
935 #ifdef CONFIG_CGROUPS
936 /* disallow userland-initiated cgroup migration */
937 unsigned no_cgroup_migration:1;
938 /* task is frozen/stopped (used by the cgroup freezer) */
939 unsigned frozen:1;
940 #endif
941 #ifdef CONFIG_BLK_CGROUP
942 unsigned use_memdelay:1;
943 #endif
944 #ifdef CONFIG_PSI
945 /* Stalled due to lack of memory */
946 unsigned in_memstall:1;
947 #endif
948 #ifdef CONFIG_PAGE_OWNER
949 /* Used by page_owner=on to detect recursion in page tracking. */
950 unsigned in_page_owner:1;
951 #endif
952 #ifdef CONFIG_EVENTFD
953 /* Recursion prevention for eventfd_signal() */
954 unsigned in_eventfd_signal:1;
955 #endif
956
957 unsigned long atomic_flags; /* Flags requiring atomic access. */
958
959 struct restart_block restart_block;
960
961 pid_t pid;
962 pid_t tgid;
963
964 #ifdef CONFIG_STACKPROTECTOR
965 /* Canary value for the -fstack-protector GCC feature: */
966 unsigned long stack_canary;
967 #endif
968 /*
969 * Pointers to the (original) parent process, youngest child, younger sibling,
970 * older sibling, respectively. (p->father can be replaced with
971 * p->real_parent->pid)
972 */
973
974 /* Real parent process: */
975 struct task_struct __rcu *real_parent;
976
977 /* Recipient of SIGCHLD, wait4() reports: */
978 struct task_struct __rcu *parent;
979
980 /*
981 * Children/sibling form the list of natural children:
982 */
983 struct list_head children;
984 struct list_head sibling;
985 struct task_struct *group_leader;
986
987 /*
988 * 'ptraced' is the list of tasks this task is using ptrace() on.
989 *
990 * This includes both natural children and PTRACE_ATTACH targets.
991 * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
992 */
993 struct list_head ptraced;
994 struct list_head ptrace_entry;
995
996 /* PID/PID hash table linkage. */
997 struct pid *thread_pid;
998 struct hlist_node pid_links[PIDTYPE_MAX];
999 struct list_head thread_group;
1000 struct list_head thread_node;
1001
1002 struct completion *vfork_done;
1003
1004 /* CLONE_CHILD_SETTID: */
1005 int __user *set_child_tid;
1006
1007 /* CLONE_CHILD_CLEARTID: */
1008 int __user *clear_child_tid;
1009
1010 /* PF_IO_WORKER */
1011 void *pf_io_worker;
1012
1013 u64 utime;
1014 u64 stime;
1015 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
1016 u64 utimescaled;
1017 u64 stimescaled;
1018 #endif
1019 u64 gtime;
1020 #ifdef CONFIG_CPU_FREQ_TIMES
1021 u64 *time_in_state;
1022 unsigned int max_state;
1023 #endif
1024 struct prev_cputime prev_cputime;
1025 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1026 struct vtime vtime;
1027 #endif
1028
1029 #ifdef CONFIG_NO_HZ_FULL
1030 atomic_t tick_dep_mask;
1031 #endif
1032 /* Context switch counts: */
1033 unsigned long nvcsw;
1034 unsigned long nivcsw;
1035
1036 /* Monotonic time in nsecs: */
1037 u64 start_time;
1038
1039 /* Boot based time in nsecs: */
1040 u64 start_boottime;
1041
1042 /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
1043 unsigned long min_flt;
1044 unsigned long maj_flt;
1045
1046 /* Empty if CONFIG_POSIX_CPUTIMERS=n */
1047 struct posix_cputimers posix_cputimers;
1048
1049 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK
1050 struct posix_cputimers_work posix_cputimers_work;
1051 #endif
1052
1053 /* Process credentials: */
1054
1055 /* Tracer's credentials at attach: */
1056 const struct cred __rcu *ptracer_cred;
1057
1058 /* Objective and real subjective task credentials (COW): */
1059 const struct cred __rcu *real_cred;
1060
1061 /* Effective (overridable) subjective task credentials (COW): */
1062 const struct cred __rcu *cred;
1063
1064 #ifdef CONFIG_KEYS
1065 /* Cached requested key. */
1066 struct key *cached_requested_key;
1067 #endif
1068
1069 /*
1070 * executable name, excluding path.
1071 *
1072 * - normally initialized setup_new_exec()
1073 * - access it with [gs]et_task_comm()
1074 * - lock it with task_lock()
1075 */
1076 char comm[TASK_COMM_LEN];
1077
1078 struct nameidata *nameidata;
1079
1080 #ifdef CONFIG_SYSVIPC
1081 struct sysv_sem sysvsem;
1082 struct sysv_shm sysvshm;
1083 #endif
1084 #ifdef CONFIG_DETECT_HUNG_TASK
1085 unsigned long last_switch_count;
1086 unsigned long last_switch_time;
1087 #endif
1088 /* Filesystem information: */
1089 struct fs_struct *fs;
1090
1091 /* Open file information: */
1092 struct files_struct *files;
1093
1094 #ifdef CONFIG_IO_URING
1095 struct io_uring_task *io_uring;
1096 #endif
1097
1098 /* Namespaces: */
1099 struct nsproxy *nsproxy;
1100
1101 /* Signal handlers: */
1102 struct signal_struct *signal;
1103 struct sighand_struct __rcu *sighand;
1104 sigset_t blocked;
1105 sigset_t real_blocked;
1106 /* Restored if set_restore_sigmask() was used: */
1107 sigset_t saved_sigmask;
1108 struct sigpending pending;
1109 unsigned long sas_ss_sp;
1110 size_t sas_ss_size;
1111 unsigned int sas_ss_flags;
1112
1113 struct callback_head *task_works;
1114
1115 #ifdef CONFIG_AUDIT
1116 #ifdef CONFIG_AUDITSYSCALL
1117 struct audit_context *audit_context;
1118 #endif
1119 kuid_t loginuid;
1120 unsigned int sessionid;
1121 #endif
1122 struct seccomp seccomp;
1123 struct syscall_user_dispatch syscall_dispatch;
1124
1125 /* Thread group tracking: */
1126 u64 parent_exec_id;
1127 u64 self_exec_id;
1128
1129 /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
1130 spinlock_t alloc_lock;
1131
1132 /* Protection of the PI data structures: */
1133 raw_spinlock_t pi_lock;
1134
1135 struct wake_q_node wake_q;
1136 int wake_q_count;
1137
1138 #ifdef CONFIG_RT_MUTEXES
1139 /* PI waiters blocked on a rt_mutex held by this task: */
1140 struct rb_root_cached pi_waiters;
1141 /* Updated under owner's pi_lock and rq lock */
1142 struct task_struct *pi_top_task;
1143 /* Deadlock detection and priority inheritance handling: */
1144 struct rt_mutex_waiter *pi_blocked_on;
1145 #endif
1146
1147 #ifdef CONFIG_DEBUG_MUTEXES
1148 /* Mutex deadlock detection: */
1149 struct mutex_waiter *blocked_on;
1150 #endif
1151
1152 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1153 int non_block_count;
1154 #endif
1155
1156 #ifdef CONFIG_TRACE_IRQFLAGS
1157 struct irqtrace_events irqtrace;
1158 unsigned int hardirq_threaded;
1159 u64 hardirq_chain_key;
1160 int softirqs_enabled;
1161 int softirq_context;
1162 int irq_config;
1163 #endif
1164 #ifdef CONFIG_PREEMPT_RT
1165 int softirq_disable_cnt;
1166 #endif
1167
1168 #ifdef CONFIG_LOCKDEP
1169 # define MAX_LOCK_DEPTH 48UL
1170 u64 curr_chain_key;
1171 int lockdep_depth;
1172 unsigned int lockdep_recursion;
1173 struct held_lock held_locks[MAX_LOCK_DEPTH];
1174 #endif
1175
1176 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP)
1177 unsigned int in_ubsan;
1178 #endif
1179
1180 /* Journalling filesystem info: */
1181 void *journal_info;
1182
1183 /* Stacked block device info: */
1184 struct bio_list *bio_list;
1185
1186 #ifdef CONFIG_BLOCK
1187 /* Stack plugging: */
1188 struct blk_plug *plug;
1189 #endif
1190
1191 /* VM state: */
1192 struct reclaim_state *reclaim_state;
1193
1194 struct backing_dev_info *backing_dev_info;
1195
1196 struct io_context *io_context;
1197
1198 #ifdef CONFIG_COMPACTION
1199 struct capture_control *capture_control;
1200 #endif
1201 /* Ptrace state: */
1202 unsigned long ptrace_message;
1203 kernel_siginfo_t *last_siginfo;
1204
1205 struct task_io_accounting ioac;
1206 #ifdef CONFIG_PSI
1207 /* Pressure stall state */
1208 unsigned int psi_flags;
1209 #endif
1210 #ifdef CONFIG_TASK_XACCT
1211 /* Accumulated RSS usage: */
1212 u64 acct_rss_mem1;
1213 /* Accumulated virtual memory usage: */
1214 u64 acct_vm_mem1;
1215 /* stime + utime since last update: */
1216 u64 acct_timexpd;
1217 #endif
1218 #ifdef CONFIG_CPUSETS
1219 /* Protected by ->alloc_lock: */
1220 nodemask_t mems_allowed;
1221 /* Sequence number to catch updates: */
1222 seqcount_spinlock_t mems_allowed_seq;
1223 int cpuset_mem_spread_rotor;
1224 int cpuset_slab_spread_rotor;
1225 #endif
1226 #ifdef CONFIG_CGROUPS
1227 /* Control Group info protected by css_set_lock: */
1228 struct css_set __rcu *cgroups;
1229 /* cg_list protected by css_set_lock and tsk->alloc_lock: */
1230 struct list_head cg_list;
1231 #endif
1232 #ifdef CONFIG_X86_CPU_RESCTRL
1233 u32 closid;
1234 u32 rmid;
1235 #endif
1236 #ifdef CONFIG_FUTEX
1237 struct robust_list_head __user *robust_list;
1238 #ifdef CONFIG_COMPAT
1239 struct compat_robust_list_head __user *compat_robust_list;
1240 #endif
1241 struct list_head pi_state_list;
1242 struct futex_pi_state *pi_state_cache;
1243 struct mutex futex_exit_mutex;
1244 unsigned int futex_state;
1245 #endif
1246 #ifdef CONFIG_PERF_EVENTS
1247 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1248 struct mutex perf_event_mutex;
1249 struct list_head perf_event_list;
1250 #endif
1251 #ifdef CONFIG_DEBUG_PREEMPT
1252 unsigned long preempt_disable_ip;
1253 #endif
1254 #ifdef CONFIG_NUMA
1255 /* Protected by alloc_lock: */
1256 struct mempolicy *mempolicy;
1257 short il_prev;
1258 short pref_node_fork;
1259 #endif
1260 #ifdef CONFIG_NUMA_BALANCING
1261 int numa_scan_seq;
1262 unsigned int numa_scan_period;
1263 unsigned int numa_scan_period_max;
1264 int numa_preferred_nid;
1265 unsigned long numa_migrate_retry;
1266 /* Migration stamp: */
1267 u64 node_stamp;
1268 u64 last_task_numa_placement;
1269 u64 last_sum_exec_runtime;
1270 struct callback_head numa_work;
1271
1272 /*
1273 * This pointer is only modified for current in syscall and
1274 * pagefault context (and for tasks being destroyed), so it can be read
1275 * from any of the following contexts:
1276 * - RCU read-side critical section
1277 * - current->numa_group from everywhere
1278 * - task's runqueue locked, task not running
1279 */
1280 struct numa_group __rcu *numa_group;
1281
1282 /*
1283 * numa_faults is an array split into four regions:
1284 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1285 * in this precise order.
1286 *
1287 * faults_memory: Exponential decaying average of faults on a per-node
1288 * basis. Scheduling placement decisions are made based on these
1289 * counts. The values remain static for the duration of a PTE scan.
1290 * faults_cpu: Track the nodes the process was running on when a NUMA
1291 * hinting fault was incurred.
1292 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1293 * during the current scan window. When the scan completes, the counts
1294 * in faults_memory and faults_cpu decay and these values are copied.
1295 */
1296 unsigned long *numa_faults;
1297 unsigned long total_numa_faults;
1298
1299 /*
1300 * numa_faults_locality tracks if faults recorded during the last
1301 * scan window were remote/local or failed to migrate. The task scan
1302 * period is adapted based on the locality of the faults with different
1303 * weights depending on whether they were shared or private faults
1304 */
1305 unsigned long numa_faults_locality[3];
1306
1307 unsigned long numa_pages_migrated;
1308 #endif /* CONFIG_NUMA_BALANCING */
1309
1310 #ifdef CONFIG_RSEQ
1311 struct rseq __user *rseq;
1312 u32 rseq_sig;
1313 /*
1314 * RmW on rseq_event_mask must be performed atomically
1315 * with respect to preemption.
1316 */
1317 unsigned long rseq_event_mask;
1318 #endif
1319
1320 struct tlbflush_unmap_batch tlb_ubc;
1321
1322 union {
1323 refcount_t rcu_users;
1324 struct rcu_head rcu;
1325 };
1326
1327 /* Cache last used pipe for splice(): */
1328 struct pipe_inode_info *splice_pipe;
1329
1330 struct page_frag task_frag;
1331
1332 #ifdef CONFIG_TASK_DELAY_ACCT
1333 struct task_delay_info *delays;
1334 #endif
1335
1336 #ifdef CONFIG_FAULT_INJECTION
1337 int make_it_fail;
1338 unsigned int fail_nth;
1339 #endif
1340 /*
1341 * When (nr_dirtied >= nr_dirtied_pause), it's time to call
1342 * balance_dirty_pages() for a dirty throttling pause:
1343 */
1344 int nr_dirtied;
1345 int nr_dirtied_pause;
1346 /* Start of a write-and-pause period: */
1347 unsigned long dirty_paused_when;
1348
1349 #ifdef CONFIG_LATENCYTOP
1350 int latency_record_count;
1351 struct latency_record latency_record[LT_SAVECOUNT];
1352 #endif
1353 /*
1354 * Time slack values; these are used to round up poll() and
1355 * select() etc timeout values. These are in nanoseconds.
1356 */
1357 u64 timer_slack_ns;
1358 u64 default_timer_slack_ns;
1359
1360 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
1361 unsigned int kasan_depth;
1362 #endif
1363
1364 #ifdef CONFIG_KCSAN
1365 struct kcsan_ctx kcsan_ctx;
1366 #ifdef CONFIG_TRACE_IRQFLAGS
1367 struct irqtrace_events kcsan_save_irqtrace;
1368 #endif
1369 #endif
1370
1371 struct kunit *kunit_test;
1372
1373 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1374 /* Index of current stored address in ret_stack: */
1375 int curr_ret_stack;
1376 int curr_ret_depth;
1377
1378 /* Stack of return addresses for return function tracing: */
1379 struct ftrace_ret_stack *ret_stack;
1380
1381 /* Timestamp for last schedule: */
1382 unsigned long long ftrace_timestamp;
1383
1384 /*
1385 * Number of functions that haven't been traced
1386 * because of depth overrun:
1387 */
1388 atomic_t trace_overrun;
1389
1390 /* Pause tracing: */
1391 atomic_t tracing_graph_pause;
1392 #endif
1393
1394 #ifdef CONFIG_TRACING
1395 /* State flags for use by tracers: */
1396 unsigned long trace;
1397
1398 /* Bitmask and counter of trace recursion: */
1399 unsigned long trace_recursion;
1400 #endif /* CONFIG_TRACING */
1401
1402 #ifdef CONFIG_KCOV
1403 /* See kernel/kcov.c for more details. */
1404
1405 /* Coverage collection mode enabled for this task (0 if disabled): */
1406 unsigned int kcov_mode;
1407
1408 /* Size of the kcov_area: */
1409 unsigned int kcov_size;
1410
1411 /* Buffer for coverage collection: */
1412 void *kcov_area;
1413
1414 /* KCOV descriptor wired with this task or NULL: */
1415 struct kcov *kcov;
1416
1417 /* KCOV common handle for remote coverage collection: */
1418 u64 kcov_handle;
1419
1420 /* KCOV sequence number: */
1421 int kcov_sequence;
1422
1423 /* Collect coverage from softirq context: */
1424 unsigned int kcov_softirq;
1425 #endif
1426
1427 #ifdef CONFIG_MEMCG
1428 struct mem_cgroup *memcg_in_oom;
1429 gfp_t memcg_oom_gfp_mask;
1430 int memcg_oom_order;
1431
1432 /* Number of pages to reclaim on returning to userland: */
1433 unsigned int memcg_nr_pages_over_high;
1434
1435 /* Used by memcontrol for targeted memcg charge: */
1436 struct mem_cgroup *active_memcg;
1437 #endif
1438
1439 #ifdef CONFIG_BLK_CGROUP
1440 struct request_queue *throttle_queue;
1441 #endif
1442
1443 #ifdef CONFIG_UPROBES
1444 struct uprobe_task *utask;
1445 #endif
1446 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1447 unsigned int sequential_io;
1448 unsigned int sequential_io_avg;
1449 #endif
1450 struct kmap_ctrl kmap_ctrl;
1451 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1452 unsigned long task_state_change;
1453 # ifdef CONFIG_PREEMPT_RT
1454 unsigned long saved_state_change;
1455 # endif
1456 #endif
1457 int pagefault_disabled;
1458 #ifdef CONFIG_MMU
1459 struct task_struct *oom_reaper_list;
1460 struct timer_list oom_reaper_timer;
1461 #endif
1462 #ifdef CONFIG_VMAP_STACK
1463 struct vm_struct *stack_vm_area;
1464 #endif
1465 #ifdef CONFIG_THREAD_INFO_IN_TASK
1466 /* A live task holds one reference: */
1467 refcount_t stack_refcount;
1468 #endif
1469 #ifdef CONFIG_LIVEPATCH
1470 int patch_state;
1471 #endif
1472 #ifdef CONFIG_SECURITY
1473 /* Used by LSM modules for access restriction: */
1474 void *security;
1475 #endif
1476 #ifdef CONFIG_BPF_SYSCALL
1477 /* Used by BPF task local storage */
1478 struct bpf_local_storage __rcu *bpf_storage;
1479 /* Used for BPF run context */
1480 struct bpf_run_ctx *bpf_ctx;
1481 #endif
1482
1483 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK
1484 unsigned long lowest_stack;
1485 unsigned long prev_lowest_stack;
1486 #endif
1487
1488 #ifdef CONFIG_X86_MCE
1489 void __user *mce_vaddr;
1490 __u64 mce_kflags;
1491 u64 mce_addr;
1492 __u64 mce_ripv : 1,
1493 mce_whole_page : 1,
1494 __mce_reserved : 62;
1495 struct callback_head mce_kill_me;
1496 int mce_count;
1497 #endif
1498 ANDROID_VENDOR_DATA_ARRAY(1, 64);
1499 ANDROID_OEM_DATA_ARRAY(1, 6);
1500
1501 #ifdef CONFIG_KRETPROBES
1502 struct llist_head kretprobe_instances;
1503 #endif
1504
1505 #ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH
1506 /*
1507 * If L1D flush is supported on mm context switch
1508 * then we use this callback head to queue kill work
1509 * to kill tasks that are not running on SMT disabled
1510 * cores
1511 */
1512 struct callback_head l1d_flush_kill;
1513 #endif
1514
1515 ANDROID_KABI_RESERVE(1);
1516 ANDROID_KABI_RESERVE(2);
1517 ANDROID_KABI_RESERVE(3);
1518 ANDROID_KABI_RESERVE(4);
1519 ANDROID_KABI_RESERVE(5);
1520 ANDROID_KABI_RESERVE(6);
1521 ANDROID_KABI_RESERVE(7);
1522 ANDROID_KABI_RESERVE(8);
1523
1524 /*
1525 * New fields for task_struct should be added above here, so that
1526 * they are included in the randomized portion of task_struct.
1527 */
1528 randomized_struct_fields_end
1529
1530 /* CPU-specific state of this task: */
1531 struct thread_struct thread;
1532
1533 /*
1534 * WARNING: on x86, 'thread_struct' contains a variable-sized
1535 * structure. It *MUST* be at the end of 'task_struct'.
1536 *
1537 * Do not put anything below here!
1538 */
1539 };
1540
task_pid(struct task_struct * task)1541 static inline struct pid *task_pid(struct task_struct *task)
1542 {
1543 return task->thread_pid;
1544 }
1545
1546 /*
1547 * the helpers to get the task's different pids as they are seen
1548 * from various namespaces
1549 *
1550 * task_xid_nr() : global id, i.e. the id seen from the init namespace;
1551 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of
1552 * current.
1553 * task_xid_nr_ns() : id seen from the ns specified;
1554 *
1555 * see also pid_nr() etc in include/linux/pid.h
1556 */
1557 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, struct pid_namespace *ns);
1558
task_pid_nr(struct task_struct * tsk)1559 static inline pid_t task_pid_nr(struct task_struct *tsk)
1560 {
1561 return tsk->pid;
1562 }
1563
task_pid_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1564 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1565 {
1566 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1567 }
1568
task_pid_vnr(struct task_struct * tsk)1569 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1570 {
1571 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1572 }
1573
1574
task_tgid_nr(struct task_struct * tsk)1575 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1576 {
1577 return tsk->tgid;
1578 }
1579
1580 /**
1581 * pid_alive - check that a task structure is not stale
1582 * @p: Task structure to be checked.
1583 *
1584 * Test if a process is not yet dead (at most zombie state)
1585 * If pid_alive fails, then pointers within the task structure
1586 * can be stale and must not be dereferenced.
1587 *
1588 * Return: 1 if the process is alive. 0 otherwise.
1589 */
pid_alive(const struct task_struct * p)1590 static inline int pid_alive(const struct task_struct *p)
1591 {
1592 return p->thread_pid != NULL;
1593 }
1594
task_pgrp_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1595 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1596 {
1597 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1598 }
1599
task_pgrp_vnr(struct task_struct * tsk)1600 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1601 {
1602 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1603 }
1604
1605
task_session_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1606 static inline pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1607 {
1608 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1609 }
1610
task_session_vnr(struct task_struct * tsk)1611 static inline pid_t task_session_vnr(struct task_struct *tsk)
1612 {
1613 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1614 }
1615
task_tgid_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1616 static inline pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1617 {
1618 return __task_pid_nr_ns(tsk, PIDTYPE_TGID, ns);
1619 }
1620
task_tgid_vnr(struct task_struct * tsk)1621 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1622 {
1623 return __task_pid_nr_ns(tsk, PIDTYPE_TGID, NULL);
1624 }
1625
task_ppid_nr_ns(const struct task_struct * tsk,struct pid_namespace * ns)1626 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1627 {
1628 pid_t pid = 0;
1629
1630 rcu_read_lock();
1631 if (pid_alive(tsk))
1632 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1633 rcu_read_unlock();
1634
1635 return pid;
1636 }
1637
task_ppid_nr(const struct task_struct * tsk)1638 static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1639 {
1640 return task_ppid_nr_ns(tsk, &init_pid_ns);
1641 }
1642
1643 /* Obsolete, do not use: */
task_pgrp_nr(struct task_struct * tsk)1644 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1645 {
1646 return task_pgrp_nr_ns(tsk, &init_pid_ns);
1647 }
1648
1649 #define TASK_REPORT_IDLE (TASK_REPORT + 1)
1650 #define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1)
1651
task_state_index(struct task_struct * tsk)1652 static inline unsigned int task_state_index(struct task_struct *tsk)
1653 {
1654 unsigned int tsk_state = READ_ONCE(tsk->__state);
1655 unsigned int state = (tsk_state | tsk->exit_state) & TASK_REPORT;
1656
1657 BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);
1658
1659 if (tsk_state == TASK_IDLE)
1660 state = TASK_REPORT_IDLE;
1661
1662 /*
1663 * We're lying here, but rather than expose a completely new task state
1664 * to userspace, we can make this appear as if the task has gone through
1665 * a regular rt_mutex_lock() call.
1666 */
1667 if (tsk_state == TASK_RTLOCK_WAIT)
1668 state = TASK_UNINTERRUPTIBLE;
1669
1670 return fls(state);
1671 }
1672
task_index_to_char(unsigned int state)1673 static inline char task_index_to_char(unsigned int state)
1674 {
1675 static const char state_char[] = "RSDTtXZPI";
1676
1677 BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1);
1678
1679 return state_char[state];
1680 }
1681
task_state_to_char(struct task_struct * tsk)1682 static inline char task_state_to_char(struct task_struct *tsk)
1683 {
1684 return task_index_to_char(task_state_index(tsk));
1685 }
1686
1687 /**
1688 * is_global_init - check if a task structure is init. Since init
1689 * is free to have sub-threads we need to check tgid.
1690 * @tsk: Task structure to be checked.
1691 *
1692 * Check if a task structure is the first user space task the kernel created.
1693 *
1694 * Return: 1 if the task structure is init. 0 otherwise.
1695 */
is_global_init(struct task_struct * tsk)1696 static inline int is_global_init(struct task_struct *tsk)
1697 {
1698 return task_tgid_nr(tsk) == 1;
1699 }
1700
1701 extern struct pid *cad_pid;
1702
1703 /*
1704 * Per process flags
1705 */
1706 #define PF_VCPU 0x00000001 /* I'm a virtual CPU */
1707 #define PF_IDLE 0x00000002 /* I am an IDLE thread */
1708 #define PF_EXITING 0x00000004 /* Getting shut down */
1709 #define PF_IO_WORKER 0x00000010 /* Task is an IO worker */
1710 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */
1711 #define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */
1712 #define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */
1713 #define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */
1714 #define PF_DUMPCORE 0x00000200 /* Dumped core */
1715 #define PF_SIGNALED 0x00000400 /* Killed by a signal */
1716 #define PF_MEMALLOC 0x00000800 /* Allocating memory */
1717 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */
1718 #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */
1719 #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */
1720 #define PF_FROZEN 0x00010000 /* Frozen for system suspend */
1721 #define PF_KSWAPD 0x00020000 /* I am kswapd */
1722 #define PF_MEMALLOC_NOFS 0x00040000 /* All allocation requests will inherit GFP_NOFS */
1723 #define PF_MEMALLOC_NOIO 0x00080000 /* All allocation requests will inherit GFP_NOIO */
1724 #define PF_LOCAL_THROTTLE 0x00100000 /* Throttle writes only against the bdi I write to,
1725 * I am cleaning dirty pages from some other bdi. */
1726 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */
1727 #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */
1728 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1729 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */
1730 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
1731 #define PF_MEMALLOC_PIN 0x10000000 /* Allocation context constrained to zones which allow long term pinning. */
1732 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */
1733 #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */
1734
1735 /*
1736 * Only the _current_ task can read/write to tsk->flags, but other
1737 * tasks can access tsk->flags in readonly mode for example
1738 * with tsk_used_math (like during threaded core dumping).
1739 * There is however an exception to this rule during ptrace
1740 * or during fork: the ptracer task is allowed to write to the
1741 * child->flags of its traced child (same goes for fork, the parent
1742 * can write to the child->flags), because we're guaranteed the
1743 * child is not running and in turn not changing child->flags
1744 * at the same time the parent does it.
1745 */
1746 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1747 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1748 #define clear_used_math() clear_stopped_child_used_math(current)
1749 #define set_used_math() set_stopped_child_used_math(current)
1750
1751 #define conditional_stopped_child_used_math(condition, child) \
1752 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1753
1754 #define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current)
1755
1756 #define copy_to_stopped_child_used_math(child) \
1757 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1758
1759 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1760 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1761 #define used_math() tsk_used_math(current)
1762
is_percpu_thread(void)1763 static __always_inline bool is_percpu_thread(void)
1764 {
1765 #ifdef CONFIG_SMP
1766 return (current->flags & PF_NO_SETAFFINITY) &&
1767 (current->nr_cpus_allowed == 1);
1768 #else
1769 return true;
1770 #endif
1771 }
1772
1773 /* Per-process atomic flags. */
1774 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */
1775 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */
1776 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */
1777 #define PFA_SPEC_SSB_DISABLE 3 /* Speculative Store Bypass disabled */
1778 #define PFA_SPEC_SSB_FORCE_DISABLE 4 /* Speculative Store Bypass force disabled*/
1779 #define PFA_SPEC_IB_DISABLE 5 /* Indirect branch speculation restricted */
1780 #define PFA_SPEC_IB_FORCE_DISABLE 6 /* Indirect branch speculation permanently restricted */
1781 #define PFA_SPEC_SSB_NOEXEC 7 /* Speculative Store Bypass clear on execve() */
1782
1783 #define TASK_PFA_TEST(name, func) \
1784 static inline bool task_##func(struct task_struct *p) \
1785 { return test_bit(PFA_##name, &p->atomic_flags); }
1786
1787 #define TASK_PFA_SET(name, func) \
1788 static inline void task_set_##func(struct task_struct *p) \
1789 { set_bit(PFA_##name, &p->atomic_flags); }
1790
1791 #define TASK_PFA_CLEAR(name, func) \
1792 static inline void task_clear_##func(struct task_struct *p) \
1793 { clear_bit(PFA_##name, &p->atomic_flags); }
1794
TASK_PFA_TEST(NO_NEW_PRIVS,no_new_privs)1795 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1796 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1797
1798 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1799 TASK_PFA_SET(SPREAD_PAGE, spread_page)
1800 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
1801
1802 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
1803 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
1804 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1805
1806 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable)
1807 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable)
1808 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable)
1809
1810 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1811 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1812 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1813
1814 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1815 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1816
1817 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable)
1818 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable)
1819 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable)
1820
1821 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1822 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1823
1824 static inline void
1825 current_restore_flags(unsigned long orig_flags, unsigned long flags)
1826 {
1827 current->flags &= ~flags;
1828 current->flags |= orig_flags & flags;
1829 }
1830
1831 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
1832 extern int task_can_attach(struct task_struct *p);
1833 extern int dl_bw_alloc(int cpu, u64 dl_bw);
1834 extern void dl_bw_free(int cpu, u64 dl_bw);
1835
1836 #ifdef CONFIG_RT_SOFTINT_OPTIMIZATION
1837 extern bool cpupri_check_rt(void);
1838 #else
cpupri_check_rt(void)1839 static inline bool cpupri_check_rt(void)
1840 {
1841 return false;
1842 }
1843 #endif
1844
1845 #ifdef CONFIG_SMP
1846 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask);
1847 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
1848 extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node);
1849 extern void release_user_cpus_ptr(struct task_struct *p);
1850 extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask);
1851 extern void force_compatible_cpus_allowed_ptr(struct task_struct *p);
1852 extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p);
1853 #else
do_set_cpus_allowed(struct task_struct * p,const struct cpumask * new_mask)1854 static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
1855 {
1856 }
set_cpus_allowed_ptr(struct task_struct * p,const struct cpumask * new_mask)1857 static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
1858 {
1859 if (!cpumask_test_cpu(0, new_mask))
1860 return -EINVAL;
1861 return 0;
1862 }
dup_user_cpus_ptr(struct task_struct * dst,struct task_struct * src,int node)1863 static inline int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node)
1864 {
1865 if (src->user_cpus_ptr)
1866 return -EINVAL;
1867 return 0;
1868 }
release_user_cpus_ptr(struct task_struct * p)1869 static inline void release_user_cpus_ptr(struct task_struct *p)
1870 {
1871 WARN_ON(p->user_cpus_ptr);
1872 }
1873
dl_task_check_affinity(struct task_struct * p,const struct cpumask * mask)1874 static inline int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask)
1875 {
1876 return 0;
1877 }
1878 #endif
1879
1880 extern int yield_to(struct task_struct *p, bool preempt);
1881 extern void set_user_nice(struct task_struct *p, long nice);
1882 extern int task_prio(const struct task_struct *p);
1883
1884 /**
1885 * task_nice - return the nice value of a given task.
1886 * @p: the task in question.
1887 *
1888 * Return: The nice value [ -20 ... 0 ... 19 ].
1889 */
task_nice(const struct task_struct * p)1890 static inline int task_nice(const struct task_struct *p)
1891 {
1892 return PRIO_TO_NICE((p)->static_prio);
1893 }
1894
1895 extern int can_nice(const struct task_struct *p, const int nice);
1896 extern int task_curr(const struct task_struct *p);
1897 extern int idle_cpu(int cpu);
1898 extern int available_idle_cpu(int cpu);
1899 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
1900 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
1901 extern void sched_set_fifo(struct task_struct *p);
1902 extern void sched_set_fifo_low(struct task_struct *p);
1903 extern void sched_set_normal(struct task_struct *p, int nice);
1904 extern int sched_setattr(struct task_struct *, const struct sched_attr *);
1905 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *);
1906 extern struct task_struct *idle_task(int cpu);
1907
1908 /**
1909 * is_idle_task - is the specified task an idle task?
1910 * @p: the task in question.
1911 *
1912 * Return: 1 if @p is an idle task. 0 otherwise.
1913 */
is_idle_task(const struct task_struct * p)1914 static __always_inline bool is_idle_task(const struct task_struct *p)
1915 {
1916 return !!(p->flags & PF_IDLE);
1917 }
1918
1919 extern struct task_struct *curr_task(int cpu);
1920 extern void ia64_set_curr_task(int cpu, struct task_struct *p);
1921
1922 void yield(void);
1923
1924 union thread_union {
1925 #ifndef CONFIG_ARCH_TASK_STRUCT_ON_STACK
1926 struct task_struct task;
1927 #endif
1928 #ifndef CONFIG_THREAD_INFO_IN_TASK
1929 struct thread_info thread_info;
1930 #endif
1931 unsigned long stack[THREAD_SIZE/sizeof(long)];
1932 };
1933
1934 #ifndef CONFIG_THREAD_INFO_IN_TASK
1935 extern struct thread_info init_thread_info;
1936 #endif
1937
1938 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];
1939
1940 #ifdef CONFIG_THREAD_INFO_IN_TASK
task_thread_info(struct task_struct * task)1941 static inline struct thread_info *task_thread_info(struct task_struct *task)
1942 {
1943 return &task->thread_info;
1944 }
1945 #elif !defined(__HAVE_THREAD_FUNCTIONS)
1946 # define task_thread_info(task) ((struct thread_info *)(task)->stack)
1947 #endif
1948
1949 /*
1950 * find a task by one of its numerical ids
1951 *
1952 * find_task_by_pid_ns():
1953 * finds a task by its pid in the specified namespace
1954 * find_task_by_vpid():
1955 * finds a task by its virtual pid
1956 *
1957 * see also find_vpid() etc in include/linux/pid.h
1958 */
1959
1960 extern struct task_struct *find_task_by_vpid(pid_t nr);
1961 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns);
1962
1963 /*
1964 * find a task by its virtual pid and get the task struct
1965 */
1966 extern struct task_struct *find_get_task_by_vpid(pid_t nr);
1967
1968 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1969 extern int wake_up_process(struct task_struct *tsk);
1970 extern void wake_up_new_task(struct task_struct *tsk);
1971
1972 #ifdef CONFIG_SMP
1973 extern void kick_process(struct task_struct *tsk);
1974 #else
kick_process(struct task_struct * tsk)1975 static inline void kick_process(struct task_struct *tsk) { }
1976 #endif
1977
1978 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
1979
set_task_comm(struct task_struct * tsk,const char * from)1980 static inline void set_task_comm(struct task_struct *tsk, const char *from)
1981 {
1982 __set_task_comm(tsk, from, false);
1983 }
1984
1985 extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk);
1986 #define get_task_comm(buf, tsk) ({ \
1987 BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN); \
1988 __get_task_comm(buf, sizeof(buf), tsk); \
1989 })
1990
1991 #ifdef CONFIG_SMP
scheduler_ipi(void)1992 static __always_inline void scheduler_ipi(void)
1993 {
1994 /*
1995 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting
1996 * TIF_NEED_RESCHED remotely (for the first time) will also send
1997 * this IPI.
1998 */
1999 preempt_fold_need_resched();
2000 }
2001 extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state);
2002 #else
scheduler_ipi(void)2003 static inline void scheduler_ipi(void) { }
wait_task_inactive(struct task_struct * p,unsigned int match_state)2004 static inline unsigned long wait_task_inactive(struct task_struct *p, unsigned int match_state)
2005 {
2006 return 1;
2007 }
2008 #endif
2009
2010 /*
2011 * Set thread flags in other task's structures.
2012 * See asm/thread_info.h for TIF_xxxx flags available:
2013 */
set_tsk_thread_flag(struct task_struct * tsk,int flag)2014 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2015 {
2016 set_ti_thread_flag(task_thread_info(tsk), flag);
2017 }
2018
clear_tsk_thread_flag(struct task_struct * tsk,int flag)2019 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2020 {
2021 clear_ti_thread_flag(task_thread_info(tsk), flag);
2022 }
2023
update_tsk_thread_flag(struct task_struct * tsk,int flag,bool value)2024 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag,
2025 bool value)
2026 {
2027 update_ti_thread_flag(task_thread_info(tsk), flag, value);
2028 }
2029
test_and_set_tsk_thread_flag(struct task_struct * tsk,int flag)2030 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2031 {
2032 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2033 }
2034
test_and_clear_tsk_thread_flag(struct task_struct * tsk,int flag)2035 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2036 {
2037 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2038 }
2039
test_tsk_thread_flag(struct task_struct * tsk,int flag)2040 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2041 {
2042 return test_ti_thread_flag(task_thread_info(tsk), flag);
2043 }
2044
set_tsk_need_resched(struct task_struct * tsk)2045 static inline void set_tsk_need_resched(struct task_struct *tsk)
2046 {
2047 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2048 }
2049
clear_tsk_need_resched(struct task_struct * tsk)2050 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2051 {
2052 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2053 }
2054
test_tsk_need_resched(struct task_struct * tsk)2055 static inline int test_tsk_need_resched(struct task_struct *tsk)
2056 {
2057 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2058 }
2059
2060 /*
2061 * cond_resched() and cond_resched_lock(): latency reduction via
2062 * explicit rescheduling in places that are safe. The return
2063 * value indicates whether a reschedule was done in fact.
2064 * cond_resched_lock() will drop the spinlock before scheduling,
2065 */
2066 #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC)
2067 extern int __cond_resched(void);
2068
2069 #ifdef CONFIG_PREEMPT_DYNAMIC
2070
2071 DECLARE_STATIC_CALL(cond_resched, __cond_resched);
2072
_cond_resched(void)2073 static __always_inline int _cond_resched(void)
2074 {
2075 return static_call_mod(cond_resched)();
2076 }
2077
2078 #else
2079
_cond_resched(void)2080 static inline int _cond_resched(void)
2081 {
2082 return __cond_resched();
2083 }
2084
2085 #endif /* CONFIG_PREEMPT_DYNAMIC */
2086
2087 #else
2088
_cond_resched(void)2089 static inline int _cond_resched(void) { return 0; }
2090
2091 #endif /* !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) */
2092
2093 #define cond_resched() ({ \
2094 ___might_sleep(__FILE__, __LINE__, 0); \
2095 _cond_resched(); \
2096 })
2097
2098 extern int __cond_resched_lock(spinlock_t *lock);
2099 extern int __cond_resched_rwlock_read(rwlock_t *lock);
2100 extern int __cond_resched_rwlock_write(rwlock_t *lock);
2101
2102 #define cond_resched_lock(lock) ({ \
2103 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
2104 __cond_resched_lock(lock); \
2105 })
2106
2107 #define cond_resched_rwlock_read(lock) ({ \
2108 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \
2109 __cond_resched_rwlock_read(lock); \
2110 })
2111
2112 #define cond_resched_rwlock_write(lock) ({ \
2113 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \
2114 __cond_resched_rwlock_write(lock); \
2115 })
2116
cond_resched_rcu(void)2117 static inline void cond_resched_rcu(void)
2118 {
2119 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
2120 rcu_read_unlock();
2121 cond_resched();
2122 rcu_read_lock();
2123 #endif
2124 }
2125
2126 /*
2127 * Does a critical section need to be broken due to another
2128 * task waiting?: (technically does not depend on CONFIG_PREEMPTION,
2129 * but a general need for low latency)
2130 */
spin_needbreak(spinlock_t * lock)2131 static inline int spin_needbreak(spinlock_t *lock)
2132 {
2133 #ifdef CONFIG_PREEMPTION
2134 return spin_is_contended(lock);
2135 #else
2136 return 0;
2137 #endif
2138 }
2139
2140 /*
2141 * Check if a rwlock is contended.
2142 * Returns non-zero if there is another task waiting on the rwlock.
2143 * Returns zero if the lock is not contended or the system / underlying
2144 * rwlock implementation does not support contention detection.
2145 * Technically does not depend on CONFIG_PREEMPTION, but a general need
2146 * for low latency.
2147 */
rwlock_needbreak(rwlock_t * lock)2148 static inline int rwlock_needbreak(rwlock_t *lock)
2149 {
2150 #ifdef CONFIG_PREEMPTION
2151 return rwlock_is_contended(lock);
2152 #else
2153 return 0;
2154 #endif
2155 }
2156
need_resched(void)2157 static __always_inline bool need_resched(void)
2158 {
2159 return unlikely(tif_need_resched());
2160 }
2161
2162 /*
2163 * Wrappers for p->thread_info->cpu access. No-op on UP.
2164 */
2165 #ifdef CONFIG_SMP
2166
task_cpu(const struct task_struct * p)2167 static inline unsigned int task_cpu(const struct task_struct *p)
2168 {
2169 #ifdef CONFIG_THREAD_INFO_IN_TASK
2170 return READ_ONCE(p->cpu);
2171 #else
2172 return READ_ONCE(task_thread_info(p)->cpu);
2173 #endif
2174 }
2175
2176 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2177
2178 #else
2179
task_cpu(const struct task_struct * p)2180 static inline unsigned int task_cpu(const struct task_struct *p)
2181 {
2182 return 0;
2183 }
2184
set_task_cpu(struct task_struct * p,unsigned int cpu)2185 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2186 {
2187 }
2188
2189 #endif /* CONFIG_SMP */
2190
2191 extern bool sched_task_on_rq(struct task_struct *p);
2192
2193 /*
2194 * In order to reduce various lock holder preemption latencies provide an
2195 * interface to see if a vCPU is currently running or not.
2196 *
2197 * This allows us to terminate optimistic spin loops and block, analogous to
2198 * the native optimistic spin heuristic of testing if the lock owner task is
2199 * running or not.
2200 */
2201 #ifndef vcpu_is_preempted
vcpu_is_preempted(int cpu)2202 static inline bool vcpu_is_preempted(int cpu)
2203 {
2204 return false;
2205 }
2206 #endif
2207
2208 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2209 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2210
2211 #ifndef TASK_SIZE_OF
2212 #define TASK_SIZE_OF(tsk) TASK_SIZE
2213 #endif
2214
2215 #ifdef CONFIG_SMP
2216 /* Returns effective CPU energy utilization, as seen by the scheduler */
2217 unsigned long sched_cpu_util(int cpu, unsigned long max);
2218 #endif /* CONFIG_SMP */
2219
2220 #ifdef CONFIG_RSEQ
2221
2222 /*
2223 * Map the event mask on the user-space ABI enum rseq_cs_flags
2224 * for direct mask checks.
2225 */
2226 enum rseq_event_mask_bits {
2227 RSEQ_EVENT_PREEMPT_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT,
2228 RSEQ_EVENT_SIGNAL_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT,
2229 RSEQ_EVENT_MIGRATE_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT,
2230 };
2231
2232 enum rseq_event_mask {
2233 RSEQ_EVENT_PREEMPT = (1U << RSEQ_EVENT_PREEMPT_BIT),
2234 RSEQ_EVENT_SIGNAL = (1U << RSEQ_EVENT_SIGNAL_BIT),
2235 RSEQ_EVENT_MIGRATE = (1U << RSEQ_EVENT_MIGRATE_BIT),
2236 };
2237
rseq_set_notify_resume(struct task_struct * t)2238 static inline void rseq_set_notify_resume(struct task_struct *t)
2239 {
2240 if (t->rseq)
2241 set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
2242 }
2243
2244 void __rseq_handle_notify_resume(struct ksignal *sig, struct pt_regs *regs);
2245
rseq_handle_notify_resume(struct ksignal * ksig,struct pt_regs * regs)2246 static inline void rseq_handle_notify_resume(struct ksignal *ksig,
2247 struct pt_regs *regs)
2248 {
2249 if (current->rseq)
2250 __rseq_handle_notify_resume(ksig, regs);
2251 }
2252
rseq_signal_deliver(struct ksignal * ksig,struct pt_regs * regs)2253 static inline void rseq_signal_deliver(struct ksignal *ksig,
2254 struct pt_regs *regs)
2255 {
2256 preempt_disable();
2257 __set_bit(RSEQ_EVENT_SIGNAL_BIT, ¤t->rseq_event_mask);
2258 preempt_enable();
2259 rseq_handle_notify_resume(ksig, regs);
2260 }
2261
2262 /* rseq_preempt() requires preemption to be disabled. */
rseq_preempt(struct task_struct * t)2263 static inline void rseq_preempt(struct task_struct *t)
2264 {
2265 __set_bit(RSEQ_EVENT_PREEMPT_BIT, &t->rseq_event_mask);
2266 rseq_set_notify_resume(t);
2267 }
2268
2269 /* rseq_migrate() requires preemption to be disabled. */
rseq_migrate(struct task_struct * t)2270 static inline void rseq_migrate(struct task_struct *t)
2271 {
2272 __set_bit(RSEQ_EVENT_MIGRATE_BIT, &t->rseq_event_mask);
2273 rseq_set_notify_resume(t);
2274 }
2275
2276 /*
2277 * If parent process has a registered restartable sequences area, the
2278 * child inherits. Unregister rseq for a clone with CLONE_VM set.
2279 */
rseq_fork(struct task_struct * t,unsigned long clone_flags)2280 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
2281 {
2282 if (clone_flags & CLONE_VM) {
2283 t->rseq = NULL;
2284 t->rseq_sig = 0;
2285 t->rseq_event_mask = 0;
2286 } else {
2287 t->rseq = current->rseq;
2288 t->rseq_sig = current->rseq_sig;
2289 t->rseq_event_mask = current->rseq_event_mask;
2290 }
2291 }
2292
rseq_execve(struct task_struct * t)2293 static inline void rseq_execve(struct task_struct *t)
2294 {
2295 t->rseq = NULL;
2296 t->rseq_sig = 0;
2297 t->rseq_event_mask = 0;
2298 }
2299
2300 #else
2301
rseq_set_notify_resume(struct task_struct * t)2302 static inline void rseq_set_notify_resume(struct task_struct *t)
2303 {
2304 }
rseq_handle_notify_resume(struct ksignal * ksig,struct pt_regs * regs)2305 static inline void rseq_handle_notify_resume(struct ksignal *ksig,
2306 struct pt_regs *regs)
2307 {
2308 }
rseq_signal_deliver(struct ksignal * ksig,struct pt_regs * regs)2309 static inline void rseq_signal_deliver(struct ksignal *ksig,
2310 struct pt_regs *regs)
2311 {
2312 }
rseq_preempt(struct task_struct * t)2313 static inline void rseq_preempt(struct task_struct *t)
2314 {
2315 }
rseq_migrate(struct task_struct * t)2316 static inline void rseq_migrate(struct task_struct *t)
2317 {
2318 }
rseq_fork(struct task_struct * t,unsigned long clone_flags)2319 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
2320 {
2321 }
rseq_execve(struct task_struct * t)2322 static inline void rseq_execve(struct task_struct *t)
2323 {
2324 }
2325
2326 #endif
2327
2328 #ifdef CONFIG_DEBUG_RSEQ
2329
2330 void rseq_syscall(struct pt_regs *regs);
2331
2332 #else
2333
rseq_syscall(struct pt_regs * regs)2334 static inline void rseq_syscall(struct pt_regs *regs)
2335 {
2336 }
2337
2338 #endif
2339
2340 const struct sched_avg *sched_trace_cfs_rq_avg(struct cfs_rq *cfs_rq);
2341 char *sched_trace_cfs_rq_path(struct cfs_rq *cfs_rq, char *str, int len);
2342 int sched_trace_cfs_rq_cpu(struct cfs_rq *cfs_rq);
2343
2344 const struct sched_avg *sched_trace_rq_avg_rt(struct rq *rq);
2345 const struct sched_avg *sched_trace_rq_avg_dl(struct rq *rq);
2346 const struct sched_avg *sched_trace_rq_avg_irq(struct rq *rq);
2347
2348 int sched_trace_rq_cpu(struct rq *rq);
2349 int sched_trace_rq_cpu_capacity(struct rq *rq);
2350 int sched_trace_rq_nr_running(struct rq *rq);
2351
2352 const struct cpumask *sched_trace_rd_span(struct root_domain *rd);
2353
2354 #ifdef CONFIG_SCHED_CORE
2355 extern void sched_core_free(struct task_struct *tsk);
2356 extern void sched_core_fork(struct task_struct *p);
2357 extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type,
2358 unsigned long uaddr);
2359 #else
sched_core_free(struct task_struct * tsk)2360 static inline void sched_core_free(struct task_struct *tsk) { }
sched_core_fork(struct task_struct * p)2361 static inline void sched_core_fork(struct task_struct *p) { }
2362 #endif
2363
2364 #endif
2365