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 } ____cacheline_aligned;
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 #ifdef CONFIG_FAIR_GROUP_SCHED
546 int depth;
547 struct sched_entity *parent;
548 /* rq on which this entity is (to be) queued: */
549 struct cfs_rq *cfs_rq;
550 /* rq "owned" by this entity/group: */
551 struct cfs_rq *my_q;
552 /* cached value of my_q->h_nr_running */
553 unsigned long runnable_weight;
554 #endif
555
556 #ifdef CONFIG_SMP
557 /*
558 * Per entity load average tracking.
559 *
560 * Put into separate cache line so it does not
561 * collide with read-mostly values above.
562 */
563 struct sched_avg avg;
564 #endif
565
566 ANDROID_KABI_RESERVE(1);
567 ANDROID_KABI_RESERVE(2);
568 ANDROID_KABI_RESERVE(3);
569 ANDROID_KABI_RESERVE(4);
570 };
571
572 struct sched_rt_entity {
573 struct list_head run_list;
574 unsigned long timeout;
575 unsigned long watchdog_stamp;
576 unsigned int time_slice;
577 unsigned short on_rq;
578 unsigned short on_list;
579
580 struct sched_rt_entity *back;
581 #ifdef CONFIG_RT_GROUP_SCHED
582 struct sched_rt_entity *parent;
583 /* rq on which this entity is (to be) queued: */
584 struct rt_rq *rt_rq;
585 /* rq "owned" by this entity/group: */
586 struct rt_rq *my_q;
587 #endif
588
589 ANDROID_KABI_RESERVE(1);
590 ANDROID_KABI_RESERVE(2);
591 ANDROID_KABI_RESERVE(3);
592 ANDROID_KABI_RESERVE(4);
593 } __randomize_layout;
594
595 struct sched_dl_entity {
596 struct rb_node rb_node;
597
598 /*
599 * Original scheduling parameters. Copied here from sched_attr
600 * during sched_setattr(), they will remain the same until
601 * the next sched_setattr().
602 */
603 u64 dl_runtime; /* Maximum runtime for each instance */
604 u64 dl_deadline; /* Relative deadline of each instance */
605 u64 dl_period; /* Separation of two instances (period) */
606 u64 dl_bw; /* dl_runtime / dl_period */
607 u64 dl_density; /* dl_runtime / dl_deadline */
608
609 /*
610 * Actual scheduling parameters. Initialized with the values above,
611 * they are continuously updated during task execution. Note that
612 * the remaining runtime could be < 0 in case we are in overrun.
613 */
614 s64 runtime; /* Remaining runtime for this instance */
615 u64 deadline; /* Absolute deadline for this instance */
616 unsigned int flags; /* Specifying the scheduler behaviour */
617
618 /*
619 * Some bool flags:
620 *
621 * @dl_throttled tells if we exhausted the runtime. If so, the
622 * task has to wait for a replenishment to be performed at the
623 * next firing of dl_timer.
624 *
625 * @dl_yielded tells if task gave up the CPU before consuming
626 * all its available runtime during the last job.
627 *
628 * @dl_non_contending tells if the task is inactive while still
629 * contributing to the active utilization. In other words, it
630 * indicates if the inactive timer has been armed and its handler
631 * has not been executed yet. This flag is useful to avoid race
632 * conditions between the inactive timer handler and the wakeup
633 * code.
634 *
635 * @dl_overrun tells if the task asked to be informed about runtime
636 * overruns.
637 */
638 unsigned int dl_throttled : 1;
639 unsigned int dl_yielded : 1;
640 unsigned int dl_non_contending : 1;
641 unsigned int dl_overrun : 1;
642
643 /*
644 * Bandwidth enforcement timer. Each -deadline task has its
645 * own bandwidth to be enforced, thus we need one timer per task.
646 */
647 struct hrtimer dl_timer;
648
649 /*
650 * Inactive timer, responsible for decreasing the active utilization
651 * at the "0-lag time". When a -deadline task blocks, it contributes
652 * to GRUB's active utilization until the "0-lag time", hence a
653 * timer is needed to decrease the active utilization at the correct
654 * time.
655 */
656 struct hrtimer inactive_timer;
657
658 #ifdef CONFIG_RT_MUTEXES
659 /*
660 * Priority Inheritance. When a DEADLINE scheduling entity is boosted
661 * pi_se points to the donor, otherwise points to the dl_se it belongs
662 * to (the original one/itself).
663 */
664 struct sched_dl_entity *pi_se;
665 #endif
666 };
667
668 #ifdef CONFIG_UCLAMP_TASK
669 /* Number of utilization clamp buckets (shorter alias) */
670 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT
671
672 /*
673 * Utilization clamp for a scheduling entity
674 * @value: clamp value "assigned" to a se
675 * @bucket_id: bucket index corresponding to the "assigned" value
676 * @active: the se is currently refcounted in a rq's bucket
677 * @user_defined: the requested clamp value comes from user-space
678 *
679 * The bucket_id is the index of the clamp bucket matching the clamp value
680 * which is pre-computed and stored to avoid expensive integer divisions from
681 * the fast path.
682 *
683 * The active bit is set whenever a task has got an "effective" value assigned,
684 * which can be different from the clamp value "requested" from user-space.
685 * This allows to know a task is refcounted in the rq's bucket corresponding
686 * to the "effective" bucket_id.
687 *
688 * The user_defined bit is set whenever a task has got a task-specific clamp
689 * value requested from userspace, i.e. the system defaults apply to this task
690 * just as a restriction. This allows to relax default clamps when a less
691 * restrictive task-specific value has been requested, thus allowing to
692 * implement a "nice" semantic. For example, a task running with a 20%
693 * default boost can still drop its own boosting to 0%.
694 */
695 struct uclamp_se {
696 unsigned int value : bits_per(SCHED_CAPACITY_SCALE);
697 unsigned int bucket_id : bits_per(UCLAMP_BUCKETS);
698 unsigned int active : 1;
699 unsigned int user_defined : 1;
700 };
701 #endif /* CONFIG_UCLAMP_TASK */
702
703 union rcu_special {
704 struct {
705 u8 blocked;
706 u8 need_qs;
707 u8 exp_hint; /* Hint for performance. */
708 u8 need_mb; /* Readers need smp_mb(). */
709 } b; /* Bits. */
710 u32 s; /* Set of bits. */
711 };
712
713 enum perf_event_task_context {
714 perf_invalid_context = -1,
715 perf_hw_context = 0,
716 perf_sw_context,
717 perf_nr_task_contexts,
718 };
719
720 struct wake_q_node {
721 struct wake_q_node *next;
722 };
723
724 struct kmap_ctrl {
725 #ifdef CONFIG_KMAP_LOCAL
726 int idx;
727 pte_t pteval[KM_MAX_IDX];
728 #endif
729 };
730
731 struct task_struct {
732 #ifdef CONFIG_THREAD_INFO_IN_TASK
733 /*
734 * For reasons of header soup (see current_thread_info()), this
735 * must be the first element of task_struct.
736 */
737 struct thread_info thread_info;
738 #endif
739 unsigned int __state;
740
741 #ifdef CONFIG_PREEMPT_RT
742 /* saved state for "spinlock sleepers" */
743 unsigned int saved_state;
744 #endif
745
746 /*
747 * This begins the randomizable portion of task_struct. Only
748 * scheduling-critical items should be added above here.
749 */
750 randomized_struct_fields_start
751
752 void *stack;
753 refcount_t usage;
754 /* Per task flags (PF_*), defined further below: */
755 unsigned int flags;
756 unsigned int ptrace;
757
758 #ifdef CONFIG_SMP
759 int on_cpu;
760 struct __call_single_node wake_entry;
761 #ifdef CONFIG_THREAD_INFO_IN_TASK
762 /* Current CPU: */
763 unsigned int cpu;
764 #endif
765 unsigned int wakee_flips;
766 unsigned long wakee_flip_decay_ts;
767 struct task_struct *last_wakee;
768
769 /*
770 * recent_used_cpu is initially set as the last CPU used by a task
771 * that wakes affine another task. Waker/wakee relationships can
772 * push tasks around a CPU where each wakeup moves to the next one.
773 * Tracking a recently used CPU allows a quick search for a recently
774 * used CPU that may be idle.
775 */
776 int recent_used_cpu;
777 int wake_cpu;
778 #endif
779 int on_rq;
780
781 int prio;
782 int static_prio;
783 int normal_prio;
784 unsigned int rt_priority;
785
786 const struct sched_class *sched_class;
787 struct sched_entity se;
788 struct sched_rt_entity rt;
789 struct sched_dl_entity dl;
790
791 #ifdef CONFIG_SCHED_CORE
792 struct rb_node core_node;
793 unsigned long core_cookie;
794 unsigned int core_occupation;
795 #endif
796
797 #ifdef CONFIG_CGROUP_SCHED
798 struct task_group *sched_task_group;
799 #endif
800
801 #ifdef CONFIG_UCLAMP_TASK
802 /*
803 * Clamp values requested for a scheduling entity.
804 * Must be updated with task_rq_lock() held.
805 */
806 struct uclamp_se uclamp_req[UCLAMP_CNT];
807 /*
808 * Effective clamp values used for a scheduling entity.
809 * Must be updated with task_rq_lock() held.
810 */
811 struct uclamp_se uclamp[UCLAMP_CNT];
812 #endif
813
814 struct sched_statistics stats;
815
816 #ifdef CONFIG_PREEMPT_NOTIFIERS
817 /* List of struct preempt_notifier: */
818 struct hlist_head preempt_notifiers;
819 #endif
820
821 #ifdef CONFIG_BLK_DEV_IO_TRACE
822 unsigned int btrace_seq;
823 #endif
824
825 unsigned int policy;
826 int nr_cpus_allowed;
827 const cpumask_t *cpus_ptr;
828 cpumask_t *user_cpus_ptr;
829 cpumask_t cpus_mask;
830 void *migration_pending;
831 #ifdef CONFIG_SMP
832 unsigned short migration_disabled;
833 #endif
834 unsigned short migration_flags;
835
836 #ifdef CONFIG_PREEMPT_RCU
837 int rcu_read_lock_nesting;
838 union rcu_special rcu_read_unlock_special;
839 struct list_head rcu_node_entry;
840 struct rcu_node *rcu_blocked_node;
841 #endif /* #ifdef CONFIG_PREEMPT_RCU */
842
843 #ifdef CONFIG_TASKS_RCU
844 unsigned long rcu_tasks_nvcsw;
845 u8 rcu_tasks_holdout;
846 u8 rcu_tasks_idx;
847 int rcu_tasks_idle_cpu;
848 struct list_head rcu_tasks_holdout_list;
849 #endif /* #ifdef CONFIG_TASKS_RCU */
850
851 #ifdef CONFIG_TASKS_TRACE_RCU
852 int trc_reader_nesting;
853 int trc_ipi_to_cpu;
854 union rcu_special trc_reader_special;
855 bool trc_reader_checked;
856 struct list_head trc_holdout_list;
857 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */
858
859 struct sched_info sched_info;
860
861 struct list_head tasks;
862 #ifdef CONFIG_SMP
863 struct plist_node pushable_tasks;
864 struct rb_node pushable_dl_tasks;
865 #endif
866
867 struct mm_struct *mm;
868 struct mm_struct *active_mm;
869
870 /* Per-thread vma caching: */
871 struct vmacache vmacache;
872
873 #ifdef SPLIT_RSS_COUNTING
874 struct task_rss_stat rss_stat;
875 #endif
876 int exit_state;
877 int exit_code;
878 int exit_signal;
879 /* The signal sent when the parent dies: */
880 int pdeath_signal;
881 /* JOBCTL_*, siglock protected: */
882 unsigned long jobctl;
883
884 /* Used for emulating ABI behavior of previous Linux versions: */
885 unsigned int personality;
886
887 /* Scheduler bits, serialized by scheduler locks: */
888 unsigned sched_reset_on_fork:1;
889 unsigned sched_contributes_to_load:1;
890 unsigned sched_migrated:1;
891 #ifdef CONFIG_PSI
892 unsigned sched_psi_wake_requeue:1;
893 #endif
894
895 /* Force alignment to the next boundary: */
896 unsigned :0;
897
898 /* Unserialized, strictly 'current' */
899
900 /*
901 * This field must not be in the scheduler word above due to wakelist
902 * queueing no longer being serialized by p->on_cpu. However:
903 *
904 * p->XXX = X; ttwu()
905 * schedule() if (p->on_rq && ..) // false
906 * smp_mb__after_spinlock(); if (smp_load_acquire(&p->on_cpu) && //true
907 * deactivate_task() ttwu_queue_wakelist())
908 * p->on_rq = 0; p->sched_remote_wakeup = Y;
909 *
910 * guarantees all stores of 'current' are visible before
911 * ->sched_remote_wakeup gets used, so it can be in this word.
912 */
913 unsigned sched_remote_wakeup:1;
914
915 /* Bit to tell LSMs we're in execve(): */
916 unsigned in_execve:1;
917 unsigned in_iowait:1;
918 #ifndef TIF_RESTORE_SIGMASK
919 unsigned restore_sigmask:1;
920 #endif
921 #ifdef CONFIG_MEMCG
922 unsigned in_user_fault:1;
923 #endif
924 #ifdef CONFIG_LRU_GEN
925 /* whether the LRU algorithm may apply to this access */
926 unsigned in_lru_fault:1;
927 #endif
928 #ifdef CONFIG_COMPAT_BRK
929 unsigned brk_randomized:1;
930 #endif
931 #ifdef CONFIG_CGROUPS
932 /* disallow userland-initiated cgroup migration */
933 unsigned no_cgroup_migration:1;
934 /* task is frozen/stopped (used by the cgroup freezer) */
935 unsigned frozen:1;
936 #endif
937 #ifdef CONFIG_BLK_CGROUP
938 unsigned use_memdelay:1;
939 #endif
940 #ifdef CONFIG_PSI
941 /* Stalled due to lack of memory */
942 unsigned in_memstall:1;
943 #endif
944 #ifdef CONFIG_PAGE_OWNER
945 /* Used by page_owner=on to detect recursion in page tracking. */
946 unsigned in_page_owner:1;
947 #endif
948 #ifdef CONFIG_EVENTFD
949 /* Recursion prevention for eventfd_signal() */
950 unsigned in_eventfd:1;
951 #endif
952
953 unsigned long atomic_flags; /* Flags requiring atomic access. */
954
955 struct restart_block restart_block;
956
957 pid_t pid;
958 pid_t tgid;
959
960 #ifdef CONFIG_STACKPROTECTOR
961 /* Canary value for the -fstack-protector GCC feature: */
962 unsigned long stack_canary;
963 #endif
964 /*
965 * Pointers to the (original) parent process, youngest child, younger sibling,
966 * older sibling, respectively. (p->father can be replaced with
967 * p->real_parent->pid)
968 */
969
970 /* Real parent process: */
971 struct task_struct __rcu *real_parent;
972
973 /* Recipient of SIGCHLD, wait4() reports: */
974 struct task_struct __rcu *parent;
975
976 /*
977 * Children/sibling form the list of natural children:
978 */
979 struct list_head children;
980 struct list_head sibling;
981 struct task_struct *group_leader;
982
983 /*
984 * 'ptraced' is the list of tasks this task is using ptrace() on.
985 *
986 * This includes both natural children and PTRACE_ATTACH targets.
987 * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
988 */
989 struct list_head ptraced;
990 struct list_head ptrace_entry;
991
992 /* PID/PID hash table linkage. */
993 struct pid *thread_pid;
994 struct hlist_node pid_links[PIDTYPE_MAX];
995 struct list_head thread_group;
996 struct list_head thread_node;
997
998 struct completion *vfork_done;
999
1000 /* CLONE_CHILD_SETTID: */
1001 int __user *set_child_tid;
1002
1003 /* CLONE_CHILD_CLEARTID: */
1004 int __user *clear_child_tid;
1005
1006 /* PF_IO_WORKER */
1007 void *pf_io_worker;
1008
1009 u64 utime;
1010 u64 stime;
1011 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
1012 u64 utimescaled;
1013 u64 stimescaled;
1014 #endif
1015 u64 gtime;
1016 #ifdef CONFIG_CPU_FREQ_TIMES
1017 u64 *time_in_state;
1018 unsigned int max_state;
1019 #endif
1020 struct prev_cputime prev_cputime;
1021 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1022 struct vtime vtime;
1023 #endif
1024
1025 #ifdef CONFIG_NO_HZ_FULL
1026 atomic_t tick_dep_mask;
1027 #endif
1028 /* Context switch counts: */
1029 unsigned long nvcsw;
1030 unsigned long nivcsw;
1031
1032 /* Monotonic time in nsecs: */
1033 u64 start_time;
1034
1035 /* Boot based time in nsecs: */
1036 u64 start_boottime;
1037
1038 /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
1039 unsigned long min_flt;
1040 unsigned long maj_flt;
1041
1042 /* Empty if CONFIG_POSIX_CPUTIMERS=n */
1043 struct posix_cputimers posix_cputimers;
1044
1045 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK
1046 struct posix_cputimers_work posix_cputimers_work;
1047 #endif
1048
1049 /* Process credentials: */
1050
1051 /* Tracer's credentials at attach: */
1052 const struct cred __rcu *ptracer_cred;
1053
1054 /* Objective and real subjective task credentials (COW): */
1055 const struct cred __rcu *real_cred;
1056
1057 /* Effective (overridable) subjective task credentials (COW): */
1058 const struct cred __rcu *cred;
1059
1060 #ifdef CONFIG_KEYS
1061 /* Cached requested key. */
1062 struct key *cached_requested_key;
1063 #endif
1064
1065 /*
1066 * executable name, excluding path.
1067 *
1068 * - normally initialized setup_new_exec()
1069 * - access it with [gs]et_task_comm()
1070 * - lock it with task_lock()
1071 */
1072 char comm[TASK_COMM_LEN];
1073
1074 struct nameidata *nameidata;
1075
1076 #ifdef CONFIG_SYSVIPC
1077 struct sysv_sem sysvsem;
1078 struct sysv_shm sysvshm;
1079 #endif
1080 #ifdef CONFIG_DETECT_HUNG_TASK
1081 unsigned long last_switch_count;
1082 unsigned long last_switch_time;
1083 #endif
1084 /* Filesystem information: */
1085 struct fs_struct *fs;
1086
1087 /* Open file information: */
1088 struct files_struct *files;
1089
1090 #ifdef CONFIG_IO_URING
1091 struct io_uring_task *io_uring;
1092 #endif
1093
1094 /* Namespaces: */
1095 struct nsproxy *nsproxy;
1096
1097 /* Signal handlers: */
1098 struct signal_struct *signal;
1099 struct sighand_struct __rcu *sighand;
1100 sigset_t blocked;
1101 sigset_t real_blocked;
1102 /* Restored if set_restore_sigmask() was used: */
1103 sigset_t saved_sigmask;
1104 struct sigpending pending;
1105 unsigned long sas_ss_sp;
1106 size_t sas_ss_size;
1107 unsigned int sas_ss_flags;
1108
1109 struct callback_head *task_works;
1110
1111 #ifdef CONFIG_AUDIT
1112 #ifdef CONFIG_AUDITSYSCALL
1113 struct audit_context *audit_context;
1114 #endif
1115 kuid_t loginuid;
1116 unsigned int sessionid;
1117 #endif
1118 struct seccomp seccomp;
1119 struct syscall_user_dispatch syscall_dispatch;
1120
1121 /* Thread group tracking: */
1122 u64 parent_exec_id;
1123 u64 self_exec_id;
1124
1125 /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
1126 spinlock_t alloc_lock;
1127
1128 /* Protection of the PI data structures: */
1129 raw_spinlock_t pi_lock;
1130
1131 struct wake_q_node wake_q;
1132 int wake_q_count;
1133
1134 #ifdef CONFIG_RT_MUTEXES
1135 /* PI waiters blocked on a rt_mutex held by this task: */
1136 struct rb_root_cached pi_waiters;
1137 /* Updated under owner's pi_lock and rq lock */
1138 struct task_struct *pi_top_task;
1139 /* Deadlock detection and priority inheritance handling: */
1140 struct rt_mutex_waiter *pi_blocked_on;
1141 #endif
1142
1143 #ifdef CONFIG_DEBUG_MUTEXES
1144 /* Mutex deadlock detection: */
1145 struct mutex_waiter *blocked_on;
1146 #endif
1147
1148 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1149 int non_block_count;
1150 #endif
1151
1152 #ifdef CONFIG_TRACE_IRQFLAGS
1153 struct irqtrace_events irqtrace;
1154 unsigned int hardirq_threaded;
1155 u64 hardirq_chain_key;
1156 int softirqs_enabled;
1157 int softirq_context;
1158 int irq_config;
1159 #endif
1160 #ifdef CONFIG_PREEMPT_RT
1161 int softirq_disable_cnt;
1162 #endif
1163
1164 #ifdef CONFIG_LOCKDEP
1165 # define MAX_LOCK_DEPTH 48UL
1166 u64 curr_chain_key;
1167 int lockdep_depth;
1168 unsigned int lockdep_recursion;
1169 struct held_lock held_locks[MAX_LOCK_DEPTH];
1170 #endif
1171
1172 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP)
1173 unsigned int in_ubsan;
1174 #endif
1175
1176 /* Journalling filesystem info: */
1177 void *journal_info;
1178
1179 /* Stacked block device info: */
1180 struct bio_list *bio_list;
1181
1182 #ifdef CONFIG_BLOCK
1183 /* Stack plugging: */
1184 struct blk_plug *plug;
1185 #endif
1186
1187 /* VM state: */
1188 struct reclaim_state *reclaim_state;
1189
1190 struct backing_dev_info *backing_dev_info;
1191
1192 struct io_context *io_context;
1193
1194 #ifdef CONFIG_COMPACTION
1195 struct capture_control *capture_control;
1196 #endif
1197 /* Ptrace state: */
1198 unsigned long ptrace_message;
1199 kernel_siginfo_t *last_siginfo;
1200
1201 struct task_io_accounting ioac;
1202 #ifdef CONFIG_PSI
1203 /* Pressure stall state */
1204 unsigned int psi_flags;
1205 #endif
1206 #ifdef CONFIG_TASK_XACCT
1207 /* Accumulated RSS usage: */
1208 u64 acct_rss_mem1;
1209 /* Accumulated virtual memory usage: */
1210 u64 acct_vm_mem1;
1211 /* stime + utime since last update: */
1212 u64 acct_timexpd;
1213 #endif
1214 #ifdef CONFIG_CPUSETS
1215 /* Protected by ->alloc_lock: */
1216 nodemask_t mems_allowed;
1217 /* Sequence number to catch updates: */
1218 seqcount_spinlock_t mems_allowed_seq;
1219 int cpuset_mem_spread_rotor;
1220 int cpuset_slab_spread_rotor;
1221 #endif
1222 #ifdef CONFIG_CGROUPS
1223 /* Control Group info protected by css_set_lock: */
1224 struct css_set __rcu *cgroups;
1225 /* cg_list protected by css_set_lock and tsk->alloc_lock: */
1226 struct list_head cg_list;
1227 #endif
1228 #ifdef CONFIG_X86_CPU_RESCTRL
1229 u32 closid;
1230 u32 rmid;
1231 #endif
1232 #ifdef CONFIG_FUTEX
1233 struct robust_list_head __user *robust_list;
1234 #ifdef CONFIG_COMPAT
1235 struct compat_robust_list_head __user *compat_robust_list;
1236 #endif
1237 struct list_head pi_state_list;
1238 struct futex_pi_state *pi_state_cache;
1239 struct mutex futex_exit_mutex;
1240 unsigned int futex_state;
1241 #endif
1242 #ifdef CONFIG_PERF_EVENTS
1243 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1244 struct mutex perf_event_mutex;
1245 struct list_head perf_event_list;
1246 #endif
1247 #ifdef CONFIG_DEBUG_PREEMPT
1248 unsigned long preempt_disable_ip;
1249 #endif
1250 #ifdef CONFIG_NUMA
1251 /* Protected by alloc_lock: */
1252 struct mempolicy *mempolicy;
1253 short il_prev;
1254 short pref_node_fork;
1255 #endif
1256 #ifdef CONFIG_NUMA_BALANCING
1257 int numa_scan_seq;
1258 unsigned int numa_scan_period;
1259 unsigned int numa_scan_period_max;
1260 int numa_preferred_nid;
1261 unsigned long numa_migrate_retry;
1262 /* Migration stamp: */
1263 u64 node_stamp;
1264 u64 last_task_numa_placement;
1265 u64 last_sum_exec_runtime;
1266 struct callback_head numa_work;
1267
1268 /*
1269 * This pointer is only modified for current in syscall and
1270 * pagefault context (and for tasks being destroyed), so it can be read
1271 * from any of the following contexts:
1272 * - RCU read-side critical section
1273 * - current->numa_group from everywhere
1274 * - task's runqueue locked, task not running
1275 */
1276 struct numa_group __rcu *numa_group;
1277
1278 /*
1279 * numa_faults is an array split into four regions:
1280 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1281 * in this precise order.
1282 *
1283 * faults_memory: Exponential decaying average of faults on a per-node
1284 * basis. Scheduling placement decisions are made based on these
1285 * counts. The values remain static for the duration of a PTE scan.
1286 * faults_cpu: Track the nodes the process was running on when a NUMA
1287 * hinting fault was incurred.
1288 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1289 * during the current scan window. When the scan completes, the counts
1290 * in faults_memory and faults_cpu decay and these values are copied.
1291 */
1292 unsigned long *numa_faults;
1293 unsigned long total_numa_faults;
1294
1295 /*
1296 * numa_faults_locality tracks if faults recorded during the last
1297 * scan window were remote/local or failed to migrate. The task scan
1298 * period is adapted based on the locality of the faults with different
1299 * weights depending on whether they were shared or private faults
1300 */
1301 unsigned long numa_faults_locality[3];
1302
1303 unsigned long numa_pages_migrated;
1304 #endif /* CONFIG_NUMA_BALANCING */
1305
1306 #ifdef CONFIG_RSEQ
1307 struct rseq __user *rseq;
1308 u32 rseq_sig;
1309 /*
1310 * RmW on rseq_event_mask must be performed atomically
1311 * with respect to preemption.
1312 */
1313 unsigned long rseq_event_mask;
1314 #endif
1315
1316 struct tlbflush_unmap_batch tlb_ubc;
1317
1318 union {
1319 refcount_t rcu_users;
1320 struct rcu_head rcu;
1321 };
1322
1323 /* Cache last used pipe for splice(): */
1324 struct pipe_inode_info *splice_pipe;
1325
1326 struct page_frag task_frag;
1327
1328 #ifdef CONFIG_TASK_DELAY_ACCT
1329 struct task_delay_info *delays;
1330 #endif
1331
1332 #ifdef CONFIG_FAULT_INJECTION
1333 int make_it_fail;
1334 unsigned int fail_nth;
1335 #endif
1336 /*
1337 * When (nr_dirtied >= nr_dirtied_pause), it's time to call
1338 * balance_dirty_pages() for a dirty throttling pause:
1339 */
1340 int nr_dirtied;
1341 int nr_dirtied_pause;
1342 /* Start of a write-and-pause period: */
1343 unsigned long dirty_paused_when;
1344
1345 #ifdef CONFIG_LATENCYTOP
1346 int latency_record_count;
1347 struct latency_record latency_record[LT_SAVECOUNT];
1348 #endif
1349 /*
1350 * Time slack values; these are used to round up poll() and
1351 * select() etc timeout values. These are in nanoseconds.
1352 */
1353 u64 timer_slack_ns;
1354 u64 default_timer_slack_ns;
1355
1356 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
1357 unsigned int kasan_depth;
1358 #endif
1359
1360 #ifdef CONFIG_KCSAN
1361 struct kcsan_ctx kcsan_ctx;
1362 #ifdef CONFIG_TRACE_IRQFLAGS
1363 struct irqtrace_events kcsan_save_irqtrace;
1364 #endif
1365 #endif
1366
1367 struct kunit *kunit_test;
1368
1369 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1370 /* Index of current stored address in ret_stack: */
1371 int curr_ret_stack;
1372 int curr_ret_depth;
1373
1374 /* Stack of return addresses for return function tracing: */
1375 struct ftrace_ret_stack *ret_stack;
1376
1377 /* Timestamp for last schedule: */
1378 unsigned long long ftrace_timestamp;
1379
1380 /*
1381 * Number of functions that haven't been traced
1382 * because of depth overrun:
1383 */
1384 atomic_t trace_overrun;
1385
1386 /* Pause tracing: */
1387 atomic_t tracing_graph_pause;
1388 #endif
1389
1390 #ifdef CONFIG_TRACING
1391 /* State flags for use by tracers: */
1392 unsigned long trace;
1393
1394 /* Bitmask and counter of trace recursion: */
1395 unsigned long trace_recursion;
1396 #endif /* CONFIG_TRACING */
1397
1398 #ifdef CONFIG_KCOV
1399 /* See kernel/kcov.c for more details. */
1400
1401 /* Coverage collection mode enabled for this task (0 if disabled): */
1402 unsigned int kcov_mode;
1403
1404 /* Size of the kcov_area: */
1405 unsigned int kcov_size;
1406
1407 /* Buffer for coverage collection: */
1408 void *kcov_area;
1409
1410 /* KCOV descriptor wired with this task or NULL: */
1411 struct kcov *kcov;
1412
1413 /* KCOV common handle for remote coverage collection: */
1414 u64 kcov_handle;
1415
1416 /* KCOV sequence number: */
1417 int kcov_sequence;
1418
1419 /* Collect coverage from softirq context: */
1420 unsigned int kcov_softirq;
1421 #endif
1422
1423 #ifdef CONFIG_MEMCG
1424 struct mem_cgroup *memcg_in_oom;
1425 gfp_t memcg_oom_gfp_mask;
1426 int memcg_oom_order;
1427
1428 /* Number of pages to reclaim on returning to userland: */
1429 unsigned int memcg_nr_pages_over_high;
1430
1431 /* Used by memcontrol for targeted memcg charge: */
1432 struct mem_cgroup *active_memcg;
1433 #endif
1434
1435 #ifdef CONFIG_BLK_CGROUP
1436 struct request_queue *throttle_queue;
1437 #endif
1438
1439 #ifdef CONFIG_UPROBES
1440 struct uprobe_task *utask;
1441 #endif
1442 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1443 unsigned int sequential_io;
1444 unsigned int sequential_io_avg;
1445 #endif
1446 struct kmap_ctrl kmap_ctrl;
1447 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1448 unsigned long task_state_change;
1449 # ifdef CONFIG_PREEMPT_RT
1450 unsigned long saved_state_change;
1451 # endif
1452 #endif
1453 int pagefault_disabled;
1454 #ifdef CONFIG_MMU
1455 struct task_struct *oom_reaper_list;
1456 struct timer_list oom_reaper_timer;
1457 #endif
1458 #ifdef CONFIG_VMAP_STACK
1459 struct vm_struct *stack_vm_area;
1460 #endif
1461 #ifdef CONFIG_THREAD_INFO_IN_TASK
1462 /* A live task holds one reference: */
1463 refcount_t stack_refcount;
1464 #endif
1465 #ifdef CONFIG_LIVEPATCH
1466 int patch_state;
1467 #endif
1468 #ifdef CONFIG_SECURITY
1469 /* Used by LSM modules for access restriction: */
1470 void *security;
1471 #endif
1472 #ifdef CONFIG_BPF_SYSCALL
1473 /* Used by BPF task local storage */
1474 struct bpf_local_storage __rcu *bpf_storage;
1475 /* Used for BPF run context */
1476 struct bpf_run_ctx *bpf_ctx;
1477 #endif
1478
1479 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK
1480 unsigned long lowest_stack;
1481 unsigned long prev_lowest_stack;
1482 #endif
1483
1484 #ifdef CONFIG_X86_MCE
1485 void __user *mce_vaddr;
1486 __u64 mce_kflags;
1487 u64 mce_addr;
1488 __u64 mce_ripv : 1,
1489 mce_whole_page : 1,
1490 __mce_reserved : 62;
1491 struct callback_head mce_kill_me;
1492 int mce_count;
1493 #endif
1494 ANDROID_VENDOR_DATA_ARRAY(1, 64);
1495 ANDROID_OEM_DATA_ARRAY(1, 6);
1496
1497 #ifdef CONFIG_KRETPROBES
1498 struct llist_head kretprobe_instances;
1499 #endif
1500
1501 #ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH
1502 /*
1503 * If L1D flush is supported on mm context switch
1504 * then we use this callback head to queue kill work
1505 * to kill tasks that are not running on SMT disabled
1506 * cores
1507 */
1508 struct callback_head l1d_flush_kill;
1509 #endif
1510
1511 ANDROID_KABI_RESERVE(1);
1512 ANDROID_KABI_RESERVE(2);
1513 ANDROID_KABI_RESERVE(3);
1514 ANDROID_KABI_RESERVE(4);
1515 ANDROID_KABI_RESERVE(5);
1516 ANDROID_KABI_RESERVE(6);
1517 ANDROID_KABI_RESERVE(7);
1518 ANDROID_KABI_RESERVE(8);
1519
1520 /*
1521 * New fields for task_struct should be added above here, so that
1522 * they are included in the randomized portion of task_struct.
1523 */
1524 randomized_struct_fields_end
1525
1526 /* CPU-specific state of this task: */
1527 struct thread_struct thread;
1528
1529 /*
1530 * WARNING: on x86, 'thread_struct' contains a variable-sized
1531 * structure. It *MUST* be at the end of 'task_struct'.
1532 *
1533 * Do not put anything below here!
1534 */
1535 };
1536
task_pid(struct task_struct * task)1537 static inline struct pid *task_pid(struct task_struct *task)
1538 {
1539 return task->thread_pid;
1540 }
1541
1542 /*
1543 * the helpers to get the task's different pids as they are seen
1544 * from various namespaces
1545 *
1546 * task_xid_nr() : global id, i.e. the id seen from the init namespace;
1547 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of
1548 * current.
1549 * task_xid_nr_ns() : id seen from the ns specified;
1550 *
1551 * see also pid_nr() etc in include/linux/pid.h
1552 */
1553 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, struct pid_namespace *ns);
1554
task_pid_nr(struct task_struct * tsk)1555 static inline pid_t task_pid_nr(struct task_struct *tsk)
1556 {
1557 return tsk->pid;
1558 }
1559
task_pid_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1560 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1561 {
1562 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1563 }
1564
task_pid_vnr(struct task_struct * tsk)1565 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1566 {
1567 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1568 }
1569
1570
task_tgid_nr(struct task_struct * tsk)1571 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1572 {
1573 return tsk->tgid;
1574 }
1575
1576 /**
1577 * pid_alive - check that a task structure is not stale
1578 * @p: Task structure to be checked.
1579 *
1580 * Test if a process is not yet dead (at most zombie state)
1581 * If pid_alive fails, then pointers within the task structure
1582 * can be stale and must not be dereferenced.
1583 *
1584 * Return: 1 if the process is alive. 0 otherwise.
1585 */
pid_alive(const struct task_struct * p)1586 static inline int pid_alive(const struct task_struct *p)
1587 {
1588 return p->thread_pid != NULL;
1589 }
1590
task_pgrp_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1591 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1592 {
1593 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1594 }
1595
task_pgrp_vnr(struct task_struct * tsk)1596 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1597 {
1598 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1599 }
1600
1601
task_session_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1602 static inline pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1603 {
1604 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1605 }
1606
task_session_vnr(struct task_struct * tsk)1607 static inline pid_t task_session_vnr(struct task_struct *tsk)
1608 {
1609 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1610 }
1611
task_tgid_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1612 static inline pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1613 {
1614 return __task_pid_nr_ns(tsk, PIDTYPE_TGID, ns);
1615 }
1616
task_tgid_vnr(struct task_struct * tsk)1617 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1618 {
1619 return __task_pid_nr_ns(tsk, PIDTYPE_TGID, NULL);
1620 }
1621
task_ppid_nr_ns(const struct task_struct * tsk,struct pid_namespace * ns)1622 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1623 {
1624 pid_t pid = 0;
1625
1626 rcu_read_lock();
1627 if (pid_alive(tsk))
1628 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1629 rcu_read_unlock();
1630
1631 return pid;
1632 }
1633
task_ppid_nr(const struct task_struct * tsk)1634 static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1635 {
1636 return task_ppid_nr_ns(tsk, &init_pid_ns);
1637 }
1638
1639 /* Obsolete, do not use: */
task_pgrp_nr(struct task_struct * tsk)1640 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1641 {
1642 return task_pgrp_nr_ns(tsk, &init_pid_ns);
1643 }
1644
1645 #define TASK_REPORT_IDLE (TASK_REPORT + 1)
1646 #define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1)
1647
task_state_index(struct task_struct * tsk)1648 static inline unsigned int task_state_index(struct task_struct *tsk)
1649 {
1650 unsigned int tsk_state = READ_ONCE(tsk->__state);
1651 unsigned int state = (tsk_state | tsk->exit_state) & TASK_REPORT;
1652
1653 BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);
1654
1655 if (tsk_state == TASK_IDLE)
1656 state = TASK_REPORT_IDLE;
1657
1658 /*
1659 * We're lying here, but rather than expose a completely new task state
1660 * to userspace, we can make this appear as if the task has gone through
1661 * a regular rt_mutex_lock() call.
1662 */
1663 if (tsk_state == TASK_RTLOCK_WAIT)
1664 state = TASK_UNINTERRUPTIBLE;
1665
1666 return fls(state);
1667 }
1668
task_index_to_char(unsigned int state)1669 static inline char task_index_to_char(unsigned int state)
1670 {
1671 static const char state_char[] = "RSDTtXZPI";
1672
1673 BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1);
1674
1675 return state_char[state];
1676 }
1677
task_state_to_char(struct task_struct * tsk)1678 static inline char task_state_to_char(struct task_struct *tsk)
1679 {
1680 return task_index_to_char(task_state_index(tsk));
1681 }
1682
1683 /**
1684 * is_global_init - check if a task structure is init. Since init
1685 * is free to have sub-threads we need to check tgid.
1686 * @tsk: Task structure to be checked.
1687 *
1688 * Check if a task structure is the first user space task the kernel created.
1689 *
1690 * Return: 1 if the task structure is init. 0 otherwise.
1691 */
is_global_init(struct task_struct * tsk)1692 static inline int is_global_init(struct task_struct *tsk)
1693 {
1694 return task_tgid_nr(tsk) == 1;
1695 }
1696
1697 extern struct pid *cad_pid;
1698
1699 /*
1700 * Per process flags
1701 */
1702 #define PF_VCPU 0x00000001 /* I'm a virtual CPU */
1703 #define PF_IDLE 0x00000002 /* I am an IDLE thread */
1704 #define PF_EXITING 0x00000004 /* Getting shut down */
1705 #define PF_IO_WORKER 0x00000010 /* Task is an IO worker */
1706 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */
1707 #define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */
1708 #define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */
1709 #define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */
1710 #define PF_DUMPCORE 0x00000200 /* Dumped core */
1711 #define PF_SIGNALED 0x00000400 /* Killed by a signal */
1712 #define PF_MEMALLOC 0x00000800 /* Allocating memory */
1713 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */
1714 #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */
1715 #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */
1716 #define PF_FROZEN 0x00010000 /* Frozen for system suspend */
1717 #define PF_KSWAPD 0x00020000 /* I am kswapd */
1718 #define PF_MEMALLOC_NOFS 0x00040000 /* All allocation requests will inherit GFP_NOFS */
1719 #define PF_MEMALLOC_NOIO 0x00080000 /* All allocation requests will inherit GFP_NOIO */
1720 #define PF_LOCAL_THROTTLE 0x00100000 /* Throttle writes only against the bdi I write to,
1721 * I am cleaning dirty pages from some other bdi. */
1722 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */
1723 #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */
1724 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1725 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */
1726 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
1727 #define PF_MEMALLOC_PIN 0x10000000 /* Allocation context constrained to zones which allow long term pinning. */
1728 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */
1729 #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */
1730
1731 /*
1732 * Only the _current_ task can read/write to tsk->flags, but other
1733 * tasks can access tsk->flags in readonly mode for example
1734 * with tsk_used_math (like during threaded core dumping).
1735 * There is however an exception to this rule during ptrace
1736 * or during fork: the ptracer task is allowed to write to the
1737 * child->flags of its traced child (same goes for fork, the parent
1738 * can write to the child->flags), because we're guaranteed the
1739 * child is not running and in turn not changing child->flags
1740 * at the same time the parent does it.
1741 */
1742 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1743 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1744 #define clear_used_math() clear_stopped_child_used_math(current)
1745 #define set_used_math() set_stopped_child_used_math(current)
1746
1747 #define conditional_stopped_child_used_math(condition, child) \
1748 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1749
1750 #define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current)
1751
1752 #define copy_to_stopped_child_used_math(child) \
1753 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1754
1755 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1756 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1757 #define used_math() tsk_used_math(current)
1758
is_percpu_thread(void)1759 static __always_inline bool is_percpu_thread(void)
1760 {
1761 #ifdef CONFIG_SMP
1762 return (current->flags & PF_NO_SETAFFINITY) &&
1763 (current->nr_cpus_allowed == 1);
1764 #else
1765 return true;
1766 #endif
1767 }
1768
1769 /* Per-process atomic flags. */
1770 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */
1771 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */
1772 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */
1773 #define PFA_SPEC_SSB_DISABLE 3 /* Speculative Store Bypass disabled */
1774 #define PFA_SPEC_SSB_FORCE_DISABLE 4 /* Speculative Store Bypass force disabled*/
1775 #define PFA_SPEC_IB_DISABLE 5 /* Indirect branch speculation restricted */
1776 #define PFA_SPEC_IB_FORCE_DISABLE 6 /* Indirect branch speculation permanently restricted */
1777 #define PFA_SPEC_SSB_NOEXEC 7 /* Speculative Store Bypass clear on execve() */
1778
1779 #define TASK_PFA_TEST(name, func) \
1780 static inline bool task_##func(struct task_struct *p) \
1781 { return test_bit(PFA_##name, &p->atomic_flags); }
1782
1783 #define TASK_PFA_SET(name, func) \
1784 static inline void task_set_##func(struct task_struct *p) \
1785 { set_bit(PFA_##name, &p->atomic_flags); }
1786
1787 #define TASK_PFA_CLEAR(name, func) \
1788 static inline void task_clear_##func(struct task_struct *p) \
1789 { clear_bit(PFA_##name, &p->atomic_flags); }
1790
TASK_PFA_TEST(NO_NEW_PRIVS,no_new_privs)1791 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1792 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1793
1794 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1795 TASK_PFA_SET(SPREAD_PAGE, spread_page)
1796 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
1797
1798 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
1799 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
1800 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1801
1802 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable)
1803 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable)
1804 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable)
1805
1806 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1807 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1808 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1809
1810 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1811 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1812
1813 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable)
1814 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable)
1815 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable)
1816
1817 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1818 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1819
1820 static inline void
1821 current_restore_flags(unsigned long orig_flags, unsigned long flags)
1822 {
1823 current->flags &= ~flags;
1824 current->flags |= orig_flags & flags;
1825 }
1826
1827 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
1828 extern int task_can_attach(struct task_struct *p);
1829 extern int dl_bw_alloc(int cpu, u64 dl_bw);
1830 extern void dl_bw_free(int cpu, u64 dl_bw);
1831
1832 #ifdef CONFIG_RT_SOFTINT_OPTIMIZATION
1833 extern bool cpupri_check_rt(void);
1834 #else
cpupri_check_rt(void)1835 static inline bool cpupri_check_rt(void)
1836 {
1837 return false;
1838 }
1839 #endif
1840
1841 #ifdef CONFIG_SMP
1842 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask);
1843 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
1844 extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node);
1845 extern void release_user_cpus_ptr(struct task_struct *p);
1846 extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask);
1847 extern void force_compatible_cpus_allowed_ptr(struct task_struct *p);
1848 extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p);
1849 #else
do_set_cpus_allowed(struct task_struct * p,const struct cpumask * new_mask)1850 static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
1851 {
1852 }
set_cpus_allowed_ptr(struct task_struct * p,const struct cpumask * new_mask)1853 static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
1854 {
1855 if (!cpumask_test_cpu(0, new_mask))
1856 return -EINVAL;
1857 return 0;
1858 }
dup_user_cpus_ptr(struct task_struct * dst,struct task_struct * src,int node)1859 static inline int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node)
1860 {
1861 if (src->user_cpus_ptr)
1862 return -EINVAL;
1863 return 0;
1864 }
release_user_cpus_ptr(struct task_struct * p)1865 static inline void release_user_cpus_ptr(struct task_struct *p)
1866 {
1867 WARN_ON(p->user_cpus_ptr);
1868 }
1869
dl_task_check_affinity(struct task_struct * p,const struct cpumask * mask)1870 static inline int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask)
1871 {
1872 return 0;
1873 }
1874 #endif
1875
1876 extern int yield_to(struct task_struct *p, bool preempt);
1877 extern void set_user_nice(struct task_struct *p, long nice);
1878 extern int task_prio(const struct task_struct *p);
1879
1880 /**
1881 * task_nice - return the nice value of a given task.
1882 * @p: the task in question.
1883 *
1884 * Return: The nice value [ -20 ... 0 ... 19 ].
1885 */
task_nice(const struct task_struct * p)1886 static inline int task_nice(const struct task_struct *p)
1887 {
1888 return PRIO_TO_NICE((p)->static_prio);
1889 }
1890
1891 extern int can_nice(const struct task_struct *p, const int nice);
1892 extern int task_curr(const struct task_struct *p);
1893 extern int idle_cpu(int cpu);
1894 extern int available_idle_cpu(int cpu);
1895 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
1896 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
1897 extern void sched_set_fifo(struct task_struct *p);
1898 extern void sched_set_fifo_low(struct task_struct *p);
1899 extern void sched_set_normal(struct task_struct *p, int nice);
1900 extern int sched_setattr(struct task_struct *, const struct sched_attr *);
1901 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *);
1902 extern struct task_struct *idle_task(int cpu);
1903
1904 /**
1905 * is_idle_task - is the specified task an idle task?
1906 * @p: the task in question.
1907 *
1908 * Return: 1 if @p is an idle task. 0 otherwise.
1909 */
is_idle_task(const struct task_struct * p)1910 static __always_inline bool is_idle_task(const struct task_struct *p)
1911 {
1912 return !!(p->flags & PF_IDLE);
1913 }
1914
1915 extern struct task_struct *curr_task(int cpu);
1916 extern void ia64_set_curr_task(int cpu, struct task_struct *p);
1917
1918 void yield(void);
1919
1920 union thread_union {
1921 #ifndef CONFIG_ARCH_TASK_STRUCT_ON_STACK
1922 struct task_struct task;
1923 #endif
1924 #ifndef CONFIG_THREAD_INFO_IN_TASK
1925 struct thread_info thread_info;
1926 #endif
1927 unsigned long stack[THREAD_SIZE/sizeof(long)];
1928 };
1929
1930 #ifndef CONFIG_THREAD_INFO_IN_TASK
1931 extern struct thread_info init_thread_info;
1932 #endif
1933
1934 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];
1935
1936 #ifdef CONFIG_THREAD_INFO_IN_TASK
task_thread_info(struct task_struct * task)1937 static inline struct thread_info *task_thread_info(struct task_struct *task)
1938 {
1939 return &task->thread_info;
1940 }
1941 #elif !defined(__HAVE_THREAD_FUNCTIONS)
1942 # define task_thread_info(task) ((struct thread_info *)(task)->stack)
1943 #endif
1944
1945 /*
1946 * find a task by one of its numerical ids
1947 *
1948 * find_task_by_pid_ns():
1949 * finds a task by its pid in the specified namespace
1950 * find_task_by_vpid():
1951 * finds a task by its virtual pid
1952 *
1953 * see also find_vpid() etc in include/linux/pid.h
1954 */
1955
1956 extern struct task_struct *find_task_by_vpid(pid_t nr);
1957 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns);
1958
1959 /*
1960 * find a task by its virtual pid and get the task struct
1961 */
1962 extern struct task_struct *find_get_task_by_vpid(pid_t nr);
1963
1964 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1965 extern int wake_up_process(struct task_struct *tsk);
1966 extern void wake_up_new_task(struct task_struct *tsk);
1967
1968 #ifdef CONFIG_SMP
1969 extern void kick_process(struct task_struct *tsk);
1970 #else
kick_process(struct task_struct * tsk)1971 static inline void kick_process(struct task_struct *tsk) { }
1972 #endif
1973
1974 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
1975
set_task_comm(struct task_struct * tsk,const char * from)1976 static inline void set_task_comm(struct task_struct *tsk, const char *from)
1977 {
1978 __set_task_comm(tsk, from, false);
1979 }
1980
1981 extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk);
1982 #define get_task_comm(buf, tsk) ({ \
1983 BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN); \
1984 __get_task_comm(buf, sizeof(buf), tsk); \
1985 })
1986
1987 #ifdef CONFIG_SMP
scheduler_ipi(void)1988 static __always_inline void scheduler_ipi(void)
1989 {
1990 /*
1991 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting
1992 * TIF_NEED_RESCHED remotely (for the first time) will also send
1993 * this IPI.
1994 */
1995 preempt_fold_need_resched();
1996 }
1997 extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state);
1998 #else
scheduler_ipi(void)1999 static inline void scheduler_ipi(void) { }
wait_task_inactive(struct task_struct * p,unsigned int match_state)2000 static inline unsigned long wait_task_inactive(struct task_struct *p, unsigned int match_state)
2001 {
2002 return 1;
2003 }
2004 #endif
2005
2006 /*
2007 * Set thread flags in other task's structures.
2008 * See asm/thread_info.h for TIF_xxxx flags available:
2009 */
set_tsk_thread_flag(struct task_struct * tsk,int flag)2010 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2011 {
2012 set_ti_thread_flag(task_thread_info(tsk), flag);
2013 }
2014
clear_tsk_thread_flag(struct task_struct * tsk,int flag)2015 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2016 {
2017 clear_ti_thread_flag(task_thread_info(tsk), flag);
2018 }
2019
update_tsk_thread_flag(struct task_struct * tsk,int flag,bool value)2020 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag,
2021 bool value)
2022 {
2023 update_ti_thread_flag(task_thread_info(tsk), flag, value);
2024 }
2025
test_and_set_tsk_thread_flag(struct task_struct * tsk,int flag)2026 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2027 {
2028 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2029 }
2030
test_and_clear_tsk_thread_flag(struct task_struct * tsk,int flag)2031 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2032 {
2033 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2034 }
2035
test_tsk_thread_flag(struct task_struct * tsk,int flag)2036 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2037 {
2038 return test_ti_thread_flag(task_thread_info(tsk), flag);
2039 }
2040
set_tsk_need_resched(struct task_struct * tsk)2041 static inline void set_tsk_need_resched(struct task_struct *tsk)
2042 {
2043 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2044 }
2045
clear_tsk_need_resched(struct task_struct * tsk)2046 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2047 {
2048 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2049 }
2050
test_tsk_need_resched(struct task_struct * tsk)2051 static inline int test_tsk_need_resched(struct task_struct *tsk)
2052 {
2053 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2054 }
2055
2056 /*
2057 * cond_resched() and cond_resched_lock(): latency reduction via
2058 * explicit rescheduling in places that are safe. The return
2059 * value indicates whether a reschedule was done in fact.
2060 * cond_resched_lock() will drop the spinlock before scheduling,
2061 */
2062 #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC)
2063 extern int __cond_resched(void);
2064
2065 #ifdef CONFIG_PREEMPT_DYNAMIC
2066
2067 DECLARE_STATIC_CALL(cond_resched, __cond_resched);
2068
_cond_resched(void)2069 static __always_inline int _cond_resched(void)
2070 {
2071 return static_call_mod(cond_resched)();
2072 }
2073
2074 #else
2075
_cond_resched(void)2076 static inline int _cond_resched(void)
2077 {
2078 return __cond_resched();
2079 }
2080
2081 #endif /* CONFIG_PREEMPT_DYNAMIC */
2082
2083 #else
2084
_cond_resched(void)2085 static inline int _cond_resched(void) { return 0; }
2086
2087 #endif /* !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) */
2088
2089 #define cond_resched() ({ \
2090 ___might_sleep(__FILE__, __LINE__, 0); \
2091 _cond_resched(); \
2092 })
2093
2094 extern int __cond_resched_lock(spinlock_t *lock);
2095 extern int __cond_resched_rwlock_read(rwlock_t *lock);
2096 extern int __cond_resched_rwlock_write(rwlock_t *lock);
2097
2098 #define cond_resched_lock(lock) ({ \
2099 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
2100 __cond_resched_lock(lock); \
2101 })
2102
2103 #define cond_resched_rwlock_read(lock) ({ \
2104 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \
2105 __cond_resched_rwlock_read(lock); \
2106 })
2107
2108 #define cond_resched_rwlock_write(lock) ({ \
2109 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \
2110 __cond_resched_rwlock_write(lock); \
2111 })
2112
cond_resched_rcu(void)2113 static inline void cond_resched_rcu(void)
2114 {
2115 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
2116 rcu_read_unlock();
2117 cond_resched();
2118 rcu_read_lock();
2119 #endif
2120 }
2121
2122 /*
2123 * Does a critical section need to be broken due to another
2124 * task waiting?: (technically does not depend on CONFIG_PREEMPTION,
2125 * but a general need for low latency)
2126 */
spin_needbreak(spinlock_t * lock)2127 static inline int spin_needbreak(spinlock_t *lock)
2128 {
2129 #ifdef CONFIG_PREEMPTION
2130 return spin_is_contended(lock);
2131 #else
2132 return 0;
2133 #endif
2134 }
2135
2136 /*
2137 * Check if a rwlock is contended.
2138 * Returns non-zero if there is another task waiting on the rwlock.
2139 * Returns zero if the lock is not contended or the system / underlying
2140 * rwlock implementation does not support contention detection.
2141 * Technically does not depend on CONFIG_PREEMPTION, but a general need
2142 * for low latency.
2143 */
rwlock_needbreak(rwlock_t * lock)2144 static inline int rwlock_needbreak(rwlock_t *lock)
2145 {
2146 #ifdef CONFIG_PREEMPTION
2147 return rwlock_is_contended(lock);
2148 #else
2149 return 0;
2150 #endif
2151 }
2152
need_resched(void)2153 static __always_inline bool need_resched(void)
2154 {
2155 return unlikely(tif_need_resched());
2156 }
2157
2158 /*
2159 * Wrappers for p->thread_info->cpu access. No-op on UP.
2160 */
2161 #ifdef CONFIG_SMP
2162
task_cpu(const struct task_struct * p)2163 static inline unsigned int task_cpu(const struct task_struct *p)
2164 {
2165 #ifdef CONFIG_THREAD_INFO_IN_TASK
2166 return READ_ONCE(p->cpu);
2167 #else
2168 return READ_ONCE(task_thread_info(p)->cpu);
2169 #endif
2170 }
2171
2172 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2173
2174 #else
2175
task_cpu(const struct task_struct * p)2176 static inline unsigned int task_cpu(const struct task_struct *p)
2177 {
2178 return 0;
2179 }
2180
set_task_cpu(struct task_struct * p,unsigned int cpu)2181 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2182 {
2183 }
2184
2185 #endif /* CONFIG_SMP */
2186
2187 extern bool sched_task_on_rq(struct task_struct *p);
2188
2189 /*
2190 * In order to reduce various lock holder preemption latencies provide an
2191 * interface to see if a vCPU is currently running or not.
2192 *
2193 * This allows us to terminate optimistic spin loops and block, analogous to
2194 * the native optimistic spin heuristic of testing if the lock owner task is
2195 * running or not.
2196 */
2197 #ifndef vcpu_is_preempted
vcpu_is_preempted(int cpu)2198 static inline bool vcpu_is_preempted(int cpu)
2199 {
2200 return false;
2201 }
2202 #endif
2203
2204 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2205 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2206
2207 #ifndef TASK_SIZE_OF
2208 #define TASK_SIZE_OF(tsk) TASK_SIZE
2209 #endif
2210
2211 #ifdef CONFIG_SMP
2212 /* Returns effective CPU energy utilization, as seen by the scheduler */
2213 unsigned long sched_cpu_util(int cpu, unsigned long max);
2214 #endif /* CONFIG_SMP */
2215
2216 #ifdef CONFIG_RSEQ
2217
2218 /*
2219 * Map the event mask on the user-space ABI enum rseq_cs_flags
2220 * for direct mask checks.
2221 */
2222 enum rseq_event_mask_bits {
2223 RSEQ_EVENT_PREEMPT_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT,
2224 RSEQ_EVENT_SIGNAL_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT,
2225 RSEQ_EVENT_MIGRATE_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT,
2226 };
2227
2228 enum rseq_event_mask {
2229 RSEQ_EVENT_PREEMPT = (1U << RSEQ_EVENT_PREEMPT_BIT),
2230 RSEQ_EVENT_SIGNAL = (1U << RSEQ_EVENT_SIGNAL_BIT),
2231 RSEQ_EVENT_MIGRATE = (1U << RSEQ_EVENT_MIGRATE_BIT),
2232 };
2233
rseq_set_notify_resume(struct task_struct * t)2234 static inline void rseq_set_notify_resume(struct task_struct *t)
2235 {
2236 if (t->rseq)
2237 set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
2238 }
2239
2240 void __rseq_handle_notify_resume(struct ksignal *sig, struct pt_regs *regs);
2241
rseq_handle_notify_resume(struct ksignal * ksig,struct pt_regs * regs)2242 static inline void rseq_handle_notify_resume(struct ksignal *ksig,
2243 struct pt_regs *regs)
2244 {
2245 if (current->rseq)
2246 __rseq_handle_notify_resume(ksig, regs);
2247 }
2248
rseq_signal_deliver(struct ksignal * ksig,struct pt_regs * regs)2249 static inline void rseq_signal_deliver(struct ksignal *ksig,
2250 struct pt_regs *regs)
2251 {
2252 preempt_disable();
2253 __set_bit(RSEQ_EVENT_SIGNAL_BIT, ¤t->rseq_event_mask);
2254 preempt_enable();
2255 rseq_handle_notify_resume(ksig, regs);
2256 }
2257
2258 /* rseq_preempt() requires preemption to be disabled. */
rseq_preempt(struct task_struct * t)2259 static inline void rseq_preempt(struct task_struct *t)
2260 {
2261 __set_bit(RSEQ_EVENT_PREEMPT_BIT, &t->rseq_event_mask);
2262 rseq_set_notify_resume(t);
2263 }
2264
2265 /* rseq_migrate() requires preemption to be disabled. */
rseq_migrate(struct task_struct * t)2266 static inline void rseq_migrate(struct task_struct *t)
2267 {
2268 __set_bit(RSEQ_EVENT_MIGRATE_BIT, &t->rseq_event_mask);
2269 rseq_set_notify_resume(t);
2270 }
2271
2272 /*
2273 * If parent process has a registered restartable sequences area, the
2274 * child inherits. Unregister rseq for a clone with CLONE_VM set.
2275 */
rseq_fork(struct task_struct * t,unsigned long clone_flags)2276 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
2277 {
2278 if (clone_flags & CLONE_VM) {
2279 t->rseq = NULL;
2280 t->rseq_sig = 0;
2281 t->rseq_event_mask = 0;
2282 } else {
2283 t->rseq = current->rseq;
2284 t->rseq_sig = current->rseq_sig;
2285 t->rseq_event_mask = current->rseq_event_mask;
2286 }
2287 }
2288
rseq_execve(struct task_struct * t)2289 static inline void rseq_execve(struct task_struct *t)
2290 {
2291 t->rseq = NULL;
2292 t->rseq_sig = 0;
2293 t->rseq_event_mask = 0;
2294 }
2295
2296 #else
2297
rseq_set_notify_resume(struct task_struct * t)2298 static inline void rseq_set_notify_resume(struct task_struct *t)
2299 {
2300 }
rseq_handle_notify_resume(struct ksignal * ksig,struct pt_regs * regs)2301 static inline void rseq_handle_notify_resume(struct ksignal *ksig,
2302 struct pt_regs *regs)
2303 {
2304 }
rseq_signal_deliver(struct ksignal * ksig,struct pt_regs * regs)2305 static inline void rseq_signal_deliver(struct ksignal *ksig,
2306 struct pt_regs *regs)
2307 {
2308 }
rseq_preempt(struct task_struct * t)2309 static inline void rseq_preempt(struct task_struct *t)
2310 {
2311 }
rseq_migrate(struct task_struct * t)2312 static inline void rseq_migrate(struct task_struct *t)
2313 {
2314 }
rseq_fork(struct task_struct * t,unsigned long clone_flags)2315 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
2316 {
2317 }
rseq_execve(struct task_struct * t)2318 static inline void rseq_execve(struct task_struct *t)
2319 {
2320 }
2321
2322 #endif
2323
2324 #ifdef CONFIG_DEBUG_RSEQ
2325
2326 void rseq_syscall(struct pt_regs *regs);
2327
2328 #else
2329
rseq_syscall(struct pt_regs * regs)2330 static inline void rseq_syscall(struct pt_regs *regs)
2331 {
2332 }
2333
2334 #endif
2335
2336 const struct sched_avg *sched_trace_cfs_rq_avg(struct cfs_rq *cfs_rq);
2337 char *sched_trace_cfs_rq_path(struct cfs_rq *cfs_rq, char *str, int len);
2338 int sched_trace_cfs_rq_cpu(struct cfs_rq *cfs_rq);
2339
2340 const struct sched_avg *sched_trace_rq_avg_rt(struct rq *rq);
2341 const struct sched_avg *sched_trace_rq_avg_dl(struct rq *rq);
2342 const struct sched_avg *sched_trace_rq_avg_irq(struct rq *rq);
2343
2344 int sched_trace_rq_cpu(struct rq *rq);
2345 int sched_trace_rq_cpu_capacity(struct rq *rq);
2346 int sched_trace_rq_nr_running(struct rq *rq);
2347
2348 const struct cpumask *sched_trace_rd_span(struct root_domain *rd);
2349
2350 #ifdef CONFIG_SCHED_CORE
2351 extern void sched_core_free(struct task_struct *tsk);
2352 extern void sched_core_fork(struct task_struct *p);
2353 extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type,
2354 unsigned long uaddr);
2355 #else
sched_core_free(struct task_struct * tsk)2356 static inline void sched_core_free(struct task_struct *tsk) { }
sched_core_fork(struct task_struct * p)2357 static inline void sched_core_fork(struct task_struct *p) { }
2358 #endif
2359
2360 #endif
2361