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 #include <asm/processor.h>
14 #include <linux/thread_info.h>
15 #include <linux/preempt.h>
16 #include <linux/cpumask_types.h>
17
18 #include <linux/cache.h>
19 #include <linux/irqflags_types.h>
20 #include <linux/smp_types.h>
21 #include <linux/pid_types.h>
22 #include <linux/sem_types.h>
23 #include <linux/shm.h>
24 #include <linux/kmsan_types.h>
25 #include <linux/mutex_types.h>
26 #include <linux/plist_types.h>
27 #include <linux/hrtimer_types.h>
28 #include <linux/timer_types.h>
29 #include <linux/seccomp_types.h>
30 #include <linux/nodemask_types.h>
31 #include <linux/refcount_types.h>
32 #include <linux/resource.h>
33 #include <linux/latencytop.h>
34 #include <linux/sched/prio.h>
35 #include <linux/sched/types.h>
36 #include <linux/signal_types.h>
37 #include <linux/syscall_user_dispatch_types.h>
38 #include <linux/mm_types_task.h>
39 #include <linux/netdevice_xmit.h>
40 #include <linux/task_io_accounting.h>
41 #include <linux/posix-timers_types.h>
42 #include <linux/restart_block.h>
43 #include <uapi/linux/rseq.h>
44 #include <linux/seqlock_types.h>
45 #include <linux/kcsan.h>
46 #include <linux/rv.h>
47 #include <linux/livepatch_sched.h>
48 #include <linux/uidgid_types.h>
49 #include <asm/kmap_size.h>
50
51 /* task_struct member predeclarations (sorted alphabetically): */
52 struct audit_context;
53 struct bio_list;
54 struct blk_plug;
55 struct bpf_local_storage;
56 struct bpf_run_ctx;
57 struct bpf_net_context;
58 struct capture_control;
59 struct cfs_rq;
60 struct fs_struct;
61 struct futex_pi_state;
62 struct io_context;
63 struct io_uring_task;
64 struct mempolicy;
65 struct nameidata;
66 struct nsproxy;
67 struct perf_event_context;
68 struct pid_namespace;
69 struct pipe_inode_info;
70 struct rcu_node;
71 struct reclaim_state;
72 struct robust_list_head;
73 struct root_domain;
74 struct rq;
75 struct sched_attr;
76 struct sched_dl_entity;
77 struct seq_file;
78 struct sighand_struct;
79 struct signal_struct;
80 struct task_delay_info;
81 struct task_group;
82 struct task_struct;
83 struct user_event_mm;
84
85 #include <linux/sched/ext.h>
86
87 /*
88 * Task state bitmask. NOTE! These bits are also
89 * encoded in fs/proc/array.c: get_task_state().
90 *
91 * We have two separate sets of flags: task->__state
92 * is about runnability, while task->exit_state are
93 * about the task exiting. Confusing, but this way
94 * modifying one set can't modify the other one by
95 * mistake.
96 */
97
98 /* Used in tsk->__state: */
99 #define TASK_RUNNING 0x00000000
100 #define TASK_INTERRUPTIBLE 0x00000001
101 #define TASK_UNINTERRUPTIBLE 0x00000002
102 #define __TASK_STOPPED 0x00000004
103 #define __TASK_TRACED 0x00000008
104 /* Used in tsk->exit_state: */
105 #define EXIT_DEAD 0x00000010
106 #define EXIT_ZOMBIE 0x00000020
107 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD)
108 /* Used in tsk->__state again: */
109 #define TASK_PARKED 0x00000040
110 #define TASK_DEAD 0x00000080
111 #define TASK_WAKEKILL 0x00000100
112 #define TASK_WAKING 0x00000200
113 #define TASK_NOLOAD 0x00000400
114 #define TASK_NEW 0x00000800
115 #define TASK_RTLOCK_WAIT 0x00001000
116 #define TASK_FREEZABLE 0x00002000
117 #define __TASK_FREEZABLE_UNSAFE (0x00004000 * IS_ENABLED(CONFIG_LOCKDEP))
118 #define TASK_FROZEN 0x00008000
119 #define TASK_STATE_MAX 0x00010000
120
121 #define TASK_ANY (TASK_STATE_MAX-1)
122
123 /*
124 * DO NOT ADD ANY NEW USERS !
125 */
126 #define TASK_FREEZABLE_UNSAFE (TASK_FREEZABLE | __TASK_FREEZABLE_UNSAFE)
127
128 /* Convenience macros for the sake of set_current_state: */
129 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
130 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)
131 #define TASK_TRACED __TASK_TRACED
132
133 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
134
135 /* Convenience macros for the sake of wake_up(): */
136 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
137
138 /* get_task_state(): */
139 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \
140 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
141 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \
142 TASK_PARKED)
143
144 #define task_is_running(task) (READ_ONCE((task)->__state) == TASK_RUNNING)
145
146 #define task_is_traced(task) ((READ_ONCE(task->jobctl) & JOBCTL_TRACED) != 0)
147 #define task_is_stopped(task) ((READ_ONCE(task->jobctl) & JOBCTL_STOPPED) != 0)
148 #define task_is_stopped_or_traced(task) ((READ_ONCE(task->jobctl) & (JOBCTL_STOPPED | JOBCTL_TRACED)) != 0)
149
150 /*
151 * Special states are those that do not use the normal wait-loop pattern. See
152 * the comment with set_special_state().
153 */
154 #define is_special_task_state(state) \
155 ((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | \
156 TASK_DEAD | TASK_FROZEN))
157
158 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
159 # define debug_normal_state_change(state_value) \
160 do { \
161 WARN_ON_ONCE(is_special_task_state(state_value)); \
162 current->task_state_change = _THIS_IP_; \
163 } while (0)
164
165 # define debug_special_state_change(state_value) \
166 do { \
167 WARN_ON_ONCE(!is_special_task_state(state_value)); \
168 current->task_state_change = _THIS_IP_; \
169 } while (0)
170
171 # define debug_rtlock_wait_set_state() \
172 do { \
173 current->saved_state_change = current->task_state_change;\
174 current->task_state_change = _THIS_IP_; \
175 } while (0)
176
177 # define debug_rtlock_wait_restore_state() \
178 do { \
179 current->task_state_change = current->saved_state_change;\
180 } while (0)
181
182 #else
183 # define debug_normal_state_change(cond) do { } while (0)
184 # define debug_special_state_change(cond) do { } while (0)
185 # define debug_rtlock_wait_set_state() do { } while (0)
186 # define debug_rtlock_wait_restore_state() do { } while (0)
187 #endif
188
189 /*
190 * set_current_state() includes a barrier so that the write of current->__state
191 * is correctly serialised wrt the caller's subsequent test of whether to
192 * actually sleep:
193 *
194 * for (;;) {
195 * set_current_state(TASK_UNINTERRUPTIBLE);
196 * if (CONDITION)
197 * break;
198 *
199 * schedule();
200 * }
201 * __set_current_state(TASK_RUNNING);
202 *
203 * If the caller does not need such serialisation (because, for instance, the
204 * CONDITION test and condition change and wakeup are under the same lock) then
205 * use __set_current_state().
206 *
207 * The above is typically ordered against the wakeup, which does:
208 *
209 * CONDITION = 1;
210 * wake_up_state(p, TASK_UNINTERRUPTIBLE);
211 *
212 * where wake_up_state()/try_to_wake_up() executes a full memory barrier before
213 * accessing p->__state.
214 *
215 * Wakeup will do: if (@state & p->__state) p->__state = TASK_RUNNING, that is,
216 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a
217 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING).
218 *
219 * However, with slightly different timing the wakeup TASK_RUNNING store can
220 * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not
221 * a problem either because that will result in one extra go around the loop
222 * and our @cond test will save the day.
223 *
224 * Also see the comments of try_to_wake_up().
225 */
226 #define __set_current_state(state_value) \
227 do { \
228 debug_normal_state_change((state_value)); \
229 WRITE_ONCE(current->__state, (state_value)); \
230 } while (0)
231
232 #define set_current_state(state_value) \
233 do { \
234 debug_normal_state_change((state_value)); \
235 smp_store_mb(current->__state, (state_value)); \
236 } while (0)
237
238 /*
239 * set_special_state() should be used for those states when the blocking task
240 * can not use the regular condition based wait-loop. In that case we must
241 * serialize against wakeups such that any possible in-flight TASK_RUNNING
242 * stores will not collide with our state change.
243 */
244 #define set_special_state(state_value) \
245 do { \
246 unsigned long flags; /* may shadow */ \
247 \
248 raw_spin_lock_irqsave(¤t->pi_lock, flags); \
249 debug_special_state_change((state_value)); \
250 WRITE_ONCE(current->__state, (state_value)); \
251 raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \
252 } while (0)
253
254 /*
255 * PREEMPT_RT specific variants for "sleeping" spin/rwlocks
256 *
257 * RT's spin/rwlock substitutions are state preserving. The state of the
258 * task when blocking on the lock is saved in task_struct::saved_state and
259 * restored after the lock has been acquired. These operations are
260 * serialized by task_struct::pi_lock against try_to_wake_up(). Any non RT
261 * lock related wakeups while the task is blocked on the lock are
262 * redirected to operate on task_struct::saved_state to ensure that these
263 * are not dropped. On restore task_struct::saved_state is set to
264 * TASK_RUNNING so any wakeup attempt redirected to saved_state will fail.
265 *
266 * The lock operation looks like this:
267 *
268 * current_save_and_set_rtlock_wait_state();
269 * for (;;) {
270 * if (try_lock())
271 * break;
272 * raw_spin_unlock_irq(&lock->wait_lock);
273 * schedule_rtlock();
274 * raw_spin_lock_irq(&lock->wait_lock);
275 * set_current_state(TASK_RTLOCK_WAIT);
276 * }
277 * current_restore_rtlock_saved_state();
278 */
279 #define current_save_and_set_rtlock_wait_state() \
280 do { \
281 lockdep_assert_irqs_disabled(); \
282 raw_spin_lock(¤t->pi_lock); \
283 current->saved_state = current->__state; \
284 debug_rtlock_wait_set_state(); \
285 WRITE_ONCE(current->__state, TASK_RTLOCK_WAIT); \
286 raw_spin_unlock(¤t->pi_lock); \
287 } while (0);
288
289 #define current_restore_rtlock_saved_state() \
290 do { \
291 lockdep_assert_irqs_disabled(); \
292 raw_spin_lock(¤t->pi_lock); \
293 debug_rtlock_wait_restore_state(); \
294 WRITE_ONCE(current->__state, current->saved_state); \
295 current->saved_state = TASK_RUNNING; \
296 raw_spin_unlock(¤t->pi_lock); \
297 } while (0);
298
299 #define get_current_state() READ_ONCE(current->__state)
300
301 /*
302 * Define the task command name length as enum, then it can be visible to
303 * BPF programs.
304 */
305 enum {
306 TASK_COMM_LEN = 16,
307 };
308
309 extern void sched_tick(void);
310
311 #define MAX_SCHEDULE_TIMEOUT LONG_MAX
312
313 extern long schedule_timeout(long timeout);
314 extern long schedule_timeout_interruptible(long timeout);
315 extern long schedule_timeout_killable(long timeout);
316 extern long schedule_timeout_uninterruptible(long timeout);
317 extern long schedule_timeout_idle(long timeout);
318 asmlinkage void schedule(void);
319 extern void schedule_preempt_disabled(void);
320 asmlinkage void preempt_schedule_irq(void);
321 #ifdef CONFIG_PREEMPT_RT
322 extern void schedule_rtlock(void);
323 #endif
324
325 extern int __must_check io_schedule_prepare(void);
326 extern void io_schedule_finish(int token);
327 extern long io_schedule_timeout(long timeout);
328 extern void io_schedule(void);
329
330 /**
331 * struct prev_cputime - snapshot of system and user cputime
332 * @utime: time spent in user mode
333 * @stime: time spent in system mode
334 * @lock: protects the above two fields
335 *
336 * Stores previous user/system time values such that we can guarantee
337 * monotonicity.
338 */
339 struct prev_cputime {
340 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
341 u64 utime;
342 u64 stime;
343 raw_spinlock_t lock;
344 #endif
345 };
346
347 enum vtime_state {
348 /* Task is sleeping or running in a CPU with VTIME inactive: */
349 VTIME_INACTIVE = 0,
350 /* Task is idle */
351 VTIME_IDLE,
352 /* Task runs in kernelspace in a CPU with VTIME active: */
353 VTIME_SYS,
354 /* Task runs in userspace in a CPU with VTIME active: */
355 VTIME_USER,
356 /* Task runs as guests in a CPU with VTIME active: */
357 VTIME_GUEST,
358 };
359
360 struct vtime {
361 seqcount_t seqcount;
362 unsigned long long starttime;
363 enum vtime_state state;
364 unsigned int cpu;
365 u64 utime;
366 u64 stime;
367 u64 gtime;
368 };
369
370 /*
371 * Utilization clamp constraints.
372 * @UCLAMP_MIN: Minimum utilization
373 * @UCLAMP_MAX: Maximum utilization
374 * @UCLAMP_CNT: Utilization clamp constraints count
375 */
376 enum uclamp_id {
377 UCLAMP_MIN = 0,
378 UCLAMP_MAX,
379 UCLAMP_CNT
380 };
381
382 #ifdef CONFIG_SMP
383 extern struct root_domain def_root_domain;
384 extern struct mutex sched_domains_mutex;
385 #endif
386
387 struct sched_param {
388 int sched_priority;
389 };
390
391 struct sched_info {
392 #ifdef CONFIG_SCHED_INFO
393 /* Cumulative counters: */
394
395 /* # of times we have run on this CPU: */
396 unsigned long pcount;
397
398 /* Time spent waiting on a runqueue: */
399 unsigned long long run_delay;
400
401 /* Timestamps: */
402
403 /* When did we last run on a CPU? */
404 unsigned long long last_arrival;
405
406 /* When were we last queued to run? */
407 unsigned long long last_queued;
408
409 #endif /* CONFIG_SCHED_INFO */
410 };
411
412 /*
413 * Integer metrics need fixed point arithmetic, e.g., sched/fair
414 * has a few: load, load_avg, util_avg, freq, and capacity.
415 *
416 * We define a basic fixed point arithmetic range, and then formalize
417 * all these metrics based on that basic range.
418 */
419 # define SCHED_FIXEDPOINT_SHIFT 10
420 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT)
421
422 /* Increase resolution of cpu_capacity calculations */
423 # define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT
424 # define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT)
425
426 struct load_weight {
427 unsigned long weight;
428 u32 inv_weight;
429 };
430
431 /*
432 * The load/runnable/util_avg accumulates an infinite geometric series
433 * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c).
434 *
435 * [load_avg definition]
436 *
437 * load_avg = runnable% * scale_load_down(load)
438 *
439 * [runnable_avg definition]
440 *
441 * runnable_avg = runnable% * SCHED_CAPACITY_SCALE
442 *
443 * [util_avg definition]
444 *
445 * util_avg = running% * SCHED_CAPACITY_SCALE
446 *
447 * where runnable% is the time ratio that a sched_entity is runnable and
448 * running% the time ratio that a sched_entity is running.
449 *
450 * For cfs_rq, they are the aggregated values of all runnable and blocked
451 * sched_entities.
452 *
453 * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU
454 * capacity scaling. The scaling is done through the rq_clock_pelt that is used
455 * for computing those signals (see update_rq_clock_pelt())
456 *
457 * N.B., the above ratios (runnable% and running%) themselves are in the
458 * range of [0, 1]. To do fixed point arithmetics, we therefore scale them
459 * to as large a range as necessary. This is for example reflected by
460 * util_avg's SCHED_CAPACITY_SCALE.
461 *
462 * [Overflow issue]
463 *
464 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
465 * with the highest load (=88761), always runnable on a single cfs_rq,
466 * and should not overflow as the number already hits PID_MAX_LIMIT.
467 *
468 * For all other cases (including 32-bit kernels), struct load_weight's
469 * weight will overflow first before we do, because:
470 *
471 * Max(load_avg) <= Max(load.weight)
472 *
473 * Then it is the load_weight's responsibility to consider overflow
474 * issues.
475 */
476 struct sched_avg {
477 u64 last_update_time;
478 u64 load_sum;
479 u64 runnable_sum;
480 u32 util_sum;
481 u32 period_contrib;
482 unsigned long load_avg;
483 unsigned long runnable_avg;
484 unsigned long util_avg;
485 unsigned int util_est;
486 } ____cacheline_aligned;
487
488 /*
489 * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg
490 * updates. When a task is dequeued, its util_est should not be updated if its
491 * util_avg has not been updated in the meantime.
492 * This information is mapped into the MSB bit of util_est at dequeue time.
493 * Since max value of util_est for a task is 1024 (PELT util_avg for a task)
494 * it is safe to use MSB.
495 */
496 #define UTIL_EST_WEIGHT_SHIFT 2
497 #define UTIL_AVG_UNCHANGED 0x80000000
498
499 struct sched_statistics {
500 #ifdef CONFIG_SCHEDSTATS
501 u64 wait_start;
502 u64 wait_max;
503 u64 wait_count;
504 u64 wait_sum;
505 u64 iowait_count;
506 u64 iowait_sum;
507
508 u64 sleep_start;
509 u64 sleep_max;
510 s64 sum_sleep_runtime;
511
512 u64 block_start;
513 u64 block_max;
514 s64 sum_block_runtime;
515
516 s64 exec_max;
517 u64 slice_max;
518
519 u64 nr_migrations_cold;
520 u64 nr_failed_migrations_affine;
521 u64 nr_failed_migrations_running;
522 u64 nr_failed_migrations_hot;
523 u64 nr_forced_migrations;
524
525 u64 nr_wakeups;
526 u64 nr_wakeups_sync;
527 u64 nr_wakeups_migrate;
528 u64 nr_wakeups_local;
529 u64 nr_wakeups_remote;
530 u64 nr_wakeups_affine;
531 u64 nr_wakeups_affine_attempts;
532 u64 nr_wakeups_passive;
533 u64 nr_wakeups_idle;
534
535 #ifdef CONFIG_SCHED_CORE
536 u64 core_forceidle_sum;
537 #endif
538 #endif /* CONFIG_SCHEDSTATS */
539 } ____cacheline_aligned;
540
541 struct sched_entity {
542 /* For load-balancing: */
543 struct load_weight load;
544 struct rb_node run_node;
545 u64 deadline;
546 u64 min_vruntime;
547 u64 min_slice;
548
549 struct list_head group_node;
550 unsigned char on_rq;
551 unsigned char sched_delayed;
552 unsigned char rel_deadline;
553 unsigned char custom_slice;
554 /* hole */
555
556 u64 exec_start;
557 u64 sum_exec_runtime;
558 u64 prev_sum_exec_runtime;
559 u64 vruntime;
560 s64 vlag;
561 u64 slice;
562
563 u64 nr_migrations;
564
565 #ifdef CONFIG_FAIR_GROUP_SCHED
566 int depth;
567 struct sched_entity *parent;
568 /* rq on which this entity is (to be) queued: */
569 struct cfs_rq *cfs_rq;
570 /* rq "owned" by this entity/group: */
571 struct cfs_rq *my_q;
572 /* cached value of my_q->h_nr_running */
573 unsigned long runnable_weight;
574 #endif
575
576 #ifdef CONFIG_SMP
577 /*
578 * Per entity load average tracking.
579 *
580 * Put into separate cache line so it does not
581 * collide with read-mostly values above.
582 */
583 struct sched_avg avg;
584 #endif
585 };
586
587 struct sched_rt_entity {
588 struct list_head run_list;
589 unsigned long timeout;
590 unsigned long watchdog_stamp;
591 unsigned int time_slice;
592 unsigned short on_rq;
593 unsigned short on_list;
594
595 struct sched_rt_entity *back;
596 #ifdef CONFIG_RT_GROUP_SCHED
597 struct sched_rt_entity *parent;
598 /* rq on which this entity is (to be) queued: */
599 struct rt_rq *rt_rq;
600 /* rq "owned" by this entity/group: */
601 struct rt_rq *my_q;
602 #endif
603 } __randomize_layout;
604
605 typedef bool (*dl_server_has_tasks_f)(struct sched_dl_entity *);
606 typedef struct task_struct *(*dl_server_pick_f)(struct sched_dl_entity *);
607
608 struct sched_dl_entity {
609 struct rb_node rb_node;
610
611 /*
612 * Original scheduling parameters. Copied here from sched_attr
613 * during sched_setattr(), they will remain the same until
614 * the next sched_setattr().
615 */
616 u64 dl_runtime; /* Maximum runtime for each instance */
617 u64 dl_deadline; /* Relative deadline of each instance */
618 u64 dl_period; /* Separation of two instances (period) */
619 u64 dl_bw; /* dl_runtime / dl_period */
620 u64 dl_density; /* dl_runtime / dl_deadline */
621
622 /*
623 * Actual scheduling parameters. Initialized with the values above,
624 * they are continuously updated during task execution. Note that
625 * the remaining runtime could be < 0 in case we are in overrun.
626 */
627 s64 runtime; /* Remaining runtime for this instance */
628 u64 deadline; /* Absolute deadline for this instance */
629 unsigned int flags; /* Specifying the scheduler behaviour */
630
631 /*
632 * Some bool flags:
633 *
634 * @dl_throttled tells if we exhausted the runtime. If so, the
635 * task has to wait for a replenishment to be performed at the
636 * next firing of dl_timer.
637 *
638 * @dl_yielded tells if task gave up the CPU before consuming
639 * all its available runtime during the last job.
640 *
641 * @dl_non_contending tells if the task is inactive while still
642 * contributing to the active utilization. In other words, it
643 * indicates if the inactive timer has been armed and its handler
644 * has not been executed yet. This flag is useful to avoid race
645 * conditions between the inactive timer handler and the wakeup
646 * code.
647 *
648 * @dl_overrun tells if the task asked to be informed about runtime
649 * overruns.
650 *
651 * @dl_server tells if this is a server entity.
652 *
653 * @dl_defer tells if this is a deferred or regular server. For
654 * now only defer server exists.
655 *
656 * @dl_defer_armed tells if the deferrable server is waiting
657 * for the replenishment timer to activate it.
658 *
659 * @dl_defer_running tells if the deferrable server is actually
660 * running, skipping the defer phase.
661 */
662 unsigned int dl_throttled : 1;
663 unsigned int dl_yielded : 1;
664 unsigned int dl_non_contending : 1;
665 unsigned int dl_overrun : 1;
666 unsigned int dl_server : 1;
667 unsigned int dl_defer : 1;
668 unsigned int dl_defer_armed : 1;
669 unsigned int dl_defer_running : 1;
670
671 /*
672 * Bandwidth enforcement timer. Each -deadline task has its
673 * own bandwidth to be enforced, thus we need one timer per task.
674 */
675 struct hrtimer dl_timer;
676
677 /*
678 * Inactive timer, responsible for decreasing the active utilization
679 * at the "0-lag time". When a -deadline task blocks, it contributes
680 * to GRUB's active utilization until the "0-lag time", hence a
681 * timer is needed to decrease the active utilization at the correct
682 * time.
683 */
684 struct hrtimer inactive_timer;
685
686 /*
687 * Bits for DL-server functionality. Also see the comment near
688 * dl_server_update().
689 *
690 * @rq the runqueue this server is for
691 *
692 * @server_has_tasks() returns true if @server_pick return a
693 * runnable task.
694 */
695 struct rq *rq;
696 dl_server_has_tasks_f server_has_tasks;
697 dl_server_pick_f server_pick_task;
698
699 #ifdef CONFIG_RT_MUTEXES
700 /*
701 * Priority Inheritance. When a DEADLINE scheduling entity is boosted
702 * pi_se points to the donor, otherwise points to the dl_se it belongs
703 * to (the original one/itself).
704 */
705 struct sched_dl_entity *pi_se;
706 #endif
707 };
708
709 #ifdef CONFIG_UCLAMP_TASK
710 /* Number of utilization clamp buckets (shorter alias) */
711 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT
712
713 /*
714 * Utilization clamp for a scheduling entity
715 * @value: clamp value "assigned" to a se
716 * @bucket_id: bucket index corresponding to the "assigned" value
717 * @active: the se is currently refcounted in a rq's bucket
718 * @user_defined: the requested clamp value comes from user-space
719 *
720 * The bucket_id is the index of the clamp bucket matching the clamp value
721 * which is pre-computed and stored to avoid expensive integer divisions from
722 * the fast path.
723 *
724 * The active bit is set whenever a task has got an "effective" value assigned,
725 * which can be different from the clamp value "requested" from user-space.
726 * This allows to know a task is refcounted in the rq's bucket corresponding
727 * to the "effective" bucket_id.
728 *
729 * The user_defined bit is set whenever a task has got a task-specific clamp
730 * value requested from userspace, i.e. the system defaults apply to this task
731 * just as a restriction. This allows to relax default clamps when a less
732 * restrictive task-specific value has been requested, thus allowing to
733 * implement a "nice" semantic. For example, a task running with a 20%
734 * default boost can still drop its own boosting to 0%.
735 */
736 struct uclamp_se {
737 unsigned int value : bits_per(SCHED_CAPACITY_SCALE);
738 unsigned int bucket_id : bits_per(UCLAMP_BUCKETS);
739 unsigned int active : 1;
740 unsigned int user_defined : 1;
741 };
742 #endif /* CONFIG_UCLAMP_TASK */
743
744 union rcu_special {
745 struct {
746 u8 blocked;
747 u8 need_qs;
748 u8 exp_hint; /* Hint for performance. */
749 u8 need_mb; /* Readers need smp_mb(). */
750 } b; /* Bits. */
751 u32 s; /* Set of bits. */
752 };
753
754 enum perf_event_task_context {
755 perf_invalid_context = -1,
756 perf_hw_context = 0,
757 perf_sw_context,
758 perf_nr_task_contexts,
759 };
760
761 /*
762 * Number of contexts where an event can trigger:
763 * task, softirq, hardirq, nmi.
764 */
765 #define PERF_NR_CONTEXTS 4
766
767 struct wake_q_node {
768 struct wake_q_node *next;
769 };
770
771 struct kmap_ctrl {
772 #ifdef CONFIG_KMAP_LOCAL
773 int idx;
774 pte_t pteval[KM_MAX_IDX];
775 #endif
776 };
777
778 struct task_struct {
779 #ifdef CONFIG_THREAD_INFO_IN_TASK
780 /*
781 * For reasons of header soup (see current_thread_info()), this
782 * must be the first element of task_struct.
783 */
784 struct thread_info thread_info;
785 #endif
786 unsigned int __state;
787
788 /* saved state for "spinlock sleepers" */
789 unsigned int saved_state;
790
791 /*
792 * This begins the randomizable portion of task_struct. Only
793 * scheduling-critical items should be added above here.
794 */
795 randomized_struct_fields_start
796
797 void *stack;
798 refcount_t usage;
799 /* Per task flags (PF_*), defined further below: */
800 unsigned int flags;
801 unsigned int ptrace;
802
803 #ifdef CONFIG_MEM_ALLOC_PROFILING
804 struct alloc_tag *alloc_tag;
805 #endif
806
807 #ifdef CONFIG_SMP
808 int on_cpu;
809 struct __call_single_node wake_entry;
810 unsigned int wakee_flips;
811 unsigned long wakee_flip_decay_ts;
812 struct task_struct *last_wakee;
813
814 /*
815 * recent_used_cpu is initially set as the last CPU used by a task
816 * that wakes affine another task. Waker/wakee relationships can
817 * push tasks around a CPU where each wakeup moves to the next one.
818 * Tracking a recently used CPU allows a quick search for a recently
819 * used CPU that may be idle.
820 */
821 int recent_used_cpu;
822 int wake_cpu;
823 #endif
824 int on_rq;
825
826 int prio;
827 int static_prio;
828 int normal_prio;
829 unsigned int rt_priority;
830
831 struct sched_entity se;
832 struct sched_rt_entity rt;
833 struct sched_dl_entity dl;
834 struct sched_dl_entity *dl_server;
835 #ifdef CONFIG_SCHED_CLASS_EXT
836 struct sched_ext_entity scx;
837 #endif
838 const struct sched_class *sched_class;
839
840 #ifdef CONFIG_SCHED_CORE
841 struct rb_node core_node;
842 unsigned long core_cookie;
843 unsigned int core_occupation;
844 #endif
845
846 #ifdef CONFIG_CGROUP_SCHED
847 struct task_group *sched_task_group;
848 #endif
849
850
851 #ifdef CONFIG_UCLAMP_TASK
852 /*
853 * Clamp values requested for a scheduling entity.
854 * Must be updated with task_rq_lock() held.
855 */
856 struct uclamp_se uclamp_req[UCLAMP_CNT];
857 /*
858 * Effective clamp values used for a scheduling entity.
859 * Must be updated with task_rq_lock() held.
860 */
861 struct uclamp_se uclamp[UCLAMP_CNT];
862 #endif
863
864 struct sched_statistics stats;
865
866 #ifdef CONFIG_PREEMPT_NOTIFIERS
867 /* List of struct preempt_notifier: */
868 struct hlist_head preempt_notifiers;
869 #endif
870
871 #ifdef CONFIG_BLK_DEV_IO_TRACE
872 unsigned int btrace_seq;
873 #endif
874
875 unsigned int policy;
876 unsigned long max_allowed_capacity;
877 int nr_cpus_allowed;
878 const cpumask_t *cpus_ptr;
879 cpumask_t *user_cpus_ptr;
880 cpumask_t cpus_mask;
881 void *migration_pending;
882 #ifdef CONFIG_SMP
883 unsigned short migration_disabled;
884 #endif
885 unsigned short migration_flags;
886
887 #ifdef CONFIG_PREEMPT_RCU
888 int rcu_read_lock_nesting;
889 union rcu_special rcu_read_unlock_special;
890 struct list_head rcu_node_entry;
891 struct rcu_node *rcu_blocked_node;
892 #endif /* #ifdef CONFIG_PREEMPT_RCU */
893
894 #ifdef CONFIG_TASKS_RCU
895 unsigned long rcu_tasks_nvcsw;
896 u8 rcu_tasks_holdout;
897 u8 rcu_tasks_idx;
898 int rcu_tasks_idle_cpu;
899 struct list_head rcu_tasks_holdout_list;
900 int rcu_tasks_exit_cpu;
901 struct list_head rcu_tasks_exit_list;
902 #endif /* #ifdef CONFIG_TASKS_RCU */
903
904 #ifdef CONFIG_TASKS_TRACE_RCU
905 int trc_reader_nesting;
906 int trc_ipi_to_cpu;
907 union rcu_special trc_reader_special;
908 struct list_head trc_holdout_list;
909 struct list_head trc_blkd_node;
910 int trc_blkd_cpu;
911 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */
912
913 struct sched_info sched_info;
914
915 struct list_head tasks;
916 #ifdef CONFIG_SMP
917 struct plist_node pushable_tasks;
918 struct rb_node pushable_dl_tasks;
919 #endif
920
921 struct mm_struct *mm;
922 struct mm_struct *active_mm;
923 struct address_space *faults_disabled_mapping;
924
925 int exit_state;
926 int exit_code;
927 int exit_signal;
928 /* The signal sent when the parent dies: */
929 int pdeath_signal;
930 /* JOBCTL_*, siglock protected: */
931 unsigned long jobctl;
932
933 /* Used for emulating ABI behavior of previous Linux versions: */
934 unsigned int personality;
935
936 /* Scheduler bits, serialized by scheduler locks: */
937 unsigned sched_reset_on_fork:1;
938 unsigned sched_contributes_to_load:1;
939 unsigned sched_migrated:1;
940
941 /* Force alignment to the next boundary: */
942 unsigned :0;
943
944 /* Unserialized, strictly 'current' */
945
946 /*
947 * This field must not be in the scheduler word above due to wakelist
948 * queueing no longer being serialized by p->on_cpu. However:
949 *
950 * p->XXX = X; ttwu()
951 * schedule() if (p->on_rq && ..) // false
952 * smp_mb__after_spinlock(); if (smp_load_acquire(&p->on_cpu) && //true
953 * deactivate_task() ttwu_queue_wakelist())
954 * p->on_rq = 0; p->sched_remote_wakeup = Y;
955 *
956 * guarantees all stores of 'current' are visible before
957 * ->sched_remote_wakeup gets used, so it can be in this word.
958 */
959 unsigned sched_remote_wakeup:1;
960 #ifdef CONFIG_RT_MUTEXES
961 unsigned sched_rt_mutex:1;
962 #endif
963
964 /* Bit to tell TOMOYO we're in execve(): */
965 unsigned in_execve:1;
966 unsigned in_iowait:1;
967 #ifndef TIF_RESTORE_SIGMASK
968 unsigned restore_sigmask:1;
969 #endif
970 #ifdef CONFIG_MEMCG_V1
971 unsigned in_user_fault:1;
972 #endif
973 #ifdef CONFIG_LRU_GEN
974 /* whether the LRU algorithm may apply to this access */
975 unsigned in_lru_fault:1;
976 #endif
977 #ifdef CONFIG_COMPAT_BRK
978 unsigned brk_randomized:1;
979 #endif
980 #ifdef CONFIG_CGROUPS
981 /* disallow userland-initiated cgroup migration */
982 unsigned no_cgroup_migration:1;
983 /* task is frozen/stopped (used by the cgroup freezer) */
984 unsigned frozen:1;
985 #endif
986 #ifdef CONFIG_BLK_CGROUP
987 unsigned use_memdelay:1;
988 #endif
989 #ifdef CONFIG_PSI
990 /* Stalled due to lack of memory */
991 unsigned in_memstall:1;
992 #endif
993 #ifdef CONFIG_PAGE_OWNER
994 /* Used by page_owner=on to detect recursion in page tracking. */
995 unsigned in_page_owner:1;
996 #endif
997 #ifdef CONFIG_EVENTFD
998 /* Recursion prevention for eventfd_signal() */
999 unsigned in_eventfd:1;
1000 #endif
1001 #ifdef CONFIG_ARCH_HAS_CPU_PASID
1002 unsigned pasid_activated:1;
1003 #endif
1004 #ifdef CONFIG_CPU_SUP_INTEL
1005 unsigned reported_split_lock:1;
1006 #endif
1007 #ifdef CONFIG_TASK_DELAY_ACCT
1008 /* delay due to memory thrashing */
1009 unsigned in_thrashing:1;
1010 #endif
1011 #ifdef CONFIG_PREEMPT_RT
1012 struct netdev_xmit net_xmit;
1013 #endif
1014 unsigned long atomic_flags; /* Flags requiring atomic access. */
1015
1016 struct restart_block restart_block;
1017
1018 pid_t pid;
1019 pid_t tgid;
1020
1021 #ifdef CONFIG_STACKPROTECTOR
1022 /* Canary value for the -fstack-protector GCC feature: */
1023 unsigned long stack_canary;
1024 #endif
1025 /*
1026 * Pointers to the (original) parent process, youngest child, younger sibling,
1027 * older sibling, respectively. (p->father can be replaced with
1028 * p->real_parent->pid)
1029 */
1030
1031 /* Real parent process: */
1032 struct task_struct __rcu *real_parent;
1033
1034 /* Recipient of SIGCHLD, wait4() reports: */
1035 struct task_struct __rcu *parent;
1036
1037 /*
1038 * Children/sibling form the list of natural children:
1039 */
1040 struct list_head children;
1041 struct list_head sibling;
1042 struct task_struct *group_leader;
1043
1044 /*
1045 * 'ptraced' is the list of tasks this task is using ptrace() on.
1046 *
1047 * This includes both natural children and PTRACE_ATTACH targets.
1048 * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
1049 */
1050 struct list_head ptraced;
1051 struct list_head ptrace_entry;
1052
1053 /* PID/PID hash table linkage. */
1054 struct pid *thread_pid;
1055 struct hlist_node pid_links[PIDTYPE_MAX];
1056 struct list_head thread_node;
1057
1058 struct completion *vfork_done;
1059
1060 /* CLONE_CHILD_SETTID: */
1061 int __user *set_child_tid;
1062
1063 /* CLONE_CHILD_CLEARTID: */
1064 int __user *clear_child_tid;
1065
1066 /* PF_KTHREAD | PF_IO_WORKER */
1067 void *worker_private;
1068
1069 u64 utime;
1070 u64 stime;
1071 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
1072 u64 utimescaled;
1073 u64 stimescaled;
1074 #endif
1075 u64 gtime;
1076 struct prev_cputime prev_cputime;
1077 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1078 struct vtime vtime;
1079 #endif
1080
1081 #ifdef CONFIG_NO_HZ_FULL
1082 atomic_t tick_dep_mask;
1083 #endif
1084 /* Context switch counts: */
1085 unsigned long nvcsw;
1086 unsigned long nivcsw;
1087
1088 /* Monotonic time in nsecs: */
1089 u64 start_time;
1090
1091 /* Boot based time in nsecs: */
1092 u64 start_boottime;
1093
1094 /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
1095 unsigned long min_flt;
1096 unsigned long maj_flt;
1097
1098 /* Empty if CONFIG_POSIX_CPUTIMERS=n */
1099 struct posix_cputimers posix_cputimers;
1100
1101 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK
1102 struct posix_cputimers_work posix_cputimers_work;
1103 #endif
1104
1105 /* Process credentials: */
1106
1107 /* Tracer's credentials at attach: */
1108 const struct cred __rcu *ptracer_cred;
1109
1110 /* Objective and real subjective task credentials (COW): */
1111 const struct cred __rcu *real_cred;
1112
1113 /* Effective (overridable) subjective task credentials (COW): */
1114 const struct cred __rcu *cred;
1115
1116 #ifdef CONFIG_KEYS
1117 /* Cached requested key. */
1118 struct key *cached_requested_key;
1119 #endif
1120
1121 /*
1122 * executable name, excluding path.
1123 *
1124 * - normally initialized setup_new_exec()
1125 * - access it with [gs]et_task_comm()
1126 * - lock it with task_lock()
1127 */
1128 char comm[TASK_COMM_LEN];
1129
1130 struct nameidata *nameidata;
1131
1132 #ifdef CONFIG_SYSVIPC
1133 struct sysv_sem sysvsem;
1134 struct sysv_shm sysvshm;
1135 #endif
1136 #ifdef CONFIG_DETECT_HUNG_TASK
1137 unsigned long last_switch_count;
1138 unsigned long last_switch_time;
1139 #endif
1140 /* Filesystem information: */
1141 struct fs_struct *fs;
1142
1143 /* Open file information: */
1144 struct files_struct *files;
1145
1146 #ifdef CONFIG_IO_URING
1147 struct io_uring_task *io_uring;
1148 #endif
1149
1150 /* Namespaces: */
1151 struct nsproxy *nsproxy;
1152
1153 /* Signal handlers: */
1154 struct signal_struct *signal;
1155 struct sighand_struct __rcu *sighand;
1156 sigset_t blocked;
1157 sigset_t real_blocked;
1158 /* Restored if set_restore_sigmask() was used: */
1159 sigset_t saved_sigmask;
1160 struct sigpending pending;
1161 unsigned long sas_ss_sp;
1162 size_t sas_ss_size;
1163 unsigned int sas_ss_flags;
1164
1165 struct callback_head *task_works;
1166
1167 #ifdef CONFIG_AUDIT
1168 #ifdef CONFIG_AUDITSYSCALL
1169 struct audit_context *audit_context;
1170 #endif
1171 kuid_t loginuid;
1172 unsigned int sessionid;
1173 #endif
1174 struct seccomp seccomp;
1175 struct syscall_user_dispatch syscall_dispatch;
1176
1177 /* Thread group tracking: */
1178 u64 parent_exec_id;
1179 u64 self_exec_id;
1180
1181 /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
1182 spinlock_t alloc_lock;
1183
1184 /* Protection of the PI data structures: */
1185 raw_spinlock_t pi_lock;
1186
1187 struct wake_q_node wake_q;
1188
1189 #ifdef CONFIG_RT_MUTEXES
1190 /* PI waiters blocked on a rt_mutex held by this task: */
1191 struct rb_root_cached pi_waiters;
1192 /* Updated under owner's pi_lock and rq lock */
1193 struct task_struct *pi_top_task;
1194 /* Deadlock detection and priority inheritance handling: */
1195 struct rt_mutex_waiter *pi_blocked_on;
1196 #endif
1197
1198 #ifdef CONFIG_DEBUG_MUTEXES
1199 /* Mutex deadlock detection: */
1200 struct mutex_waiter *blocked_on;
1201 #endif
1202
1203 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1204 int non_block_count;
1205 #endif
1206
1207 #ifdef CONFIG_TRACE_IRQFLAGS
1208 struct irqtrace_events irqtrace;
1209 unsigned int hardirq_threaded;
1210 u64 hardirq_chain_key;
1211 int softirqs_enabled;
1212 int softirq_context;
1213 int irq_config;
1214 #endif
1215 #ifdef CONFIG_PREEMPT_RT
1216 int softirq_disable_cnt;
1217 #endif
1218
1219 #ifdef CONFIG_LOCKDEP
1220 # define MAX_LOCK_DEPTH 48UL
1221 u64 curr_chain_key;
1222 int lockdep_depth;
1223 unsigned int lockdep_recursion;
1224 struct held_lock held_locks[MAX_LOCK_DEPTH];
1225 #endif
1226
1227 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP)
1228 unsigned int in_ubsan;
1229 #endif
1230
1231 /* Journalling filesystem info: */
1232 void *journal_info;
1233
1234 /* Stacked block device info: */
1235 struct bio_list *bio_list;
1236
1237 /* Stack plugging: */
1238 struct blk_plug *plug;
1239
1240 /* VM state: */
1241 struct reclaim_state *reclaim_state;
1242
1243 struct io_context *io_context;
1244
1245 #ifdef CONFIG_COMPACTION
1246 struct capture_control *capture_control;
1247 #endif
1248 /* Ptrace state: */
1249 unsigned long ptrace_message;
1250 kernel_siginfo_t *last_siginfo;
1251
1252 struct task_io_accounting ioac;
1253 #ifdef CONFIG_PSI
1254 /* Pressure stall state */
1255 unsigned int psi_flags;
1256 #endif
1257 #ifdef CONFIG_TASK_XACCT
1258 /* Accumulated RSS usage: */
1259 u64 acct_rss_mem1;
1260 /* Accumulated virtual memory usage: */
1261 u64 acct_vm_mem1;
1262 /* stime + utime since last update: */
1263 u64 acct_timexpd;
1264 #endif
1265 #ifdef CONFIG_CPUSETS
1266 /* Protected by ->alloc_lock: */
1267 nodemask_t mems_allowed;
1268 /* Sequence number to catch updates: */
1269 seqcount_spinlock_t mems_allowed_seq;
1270 int cpuset_mem_spread_rotor;
1271 #endif
1272 #ifdef CONFIG_CGROUPS
1273 /* Control Group info protected by css_set_lock: */
1274 struct css_set __rcu *cgroups;
1275 /* cg_list protected by css_set_lock and tsk->alloc_lock: */
1276 struct list_head cg_list;
1277 #endif
1278 #ifdef CONFIG_X86_CPU_RESCTRL
1279 u32 closid;
1280 u32 rmid;
1281 #endif
1282 #ifdef CONFIG_FUTEX
1283 struct robust_list_head __user *robust_list;
1284 #ifdef CONFIG_COMPAT
1285 struct compat_robust_list_head __user *compat_robust_list;
1286 #endif
1287 struct list_head pi_state_list;
1288 struct futex_pi_state *pi_state_cache;
1289 struct mutex futex_exit_mutex;
1290 unsigned int futex_state;
1291 #endif
1292 #ifdef CONFIG_PERF_EVENTS
1293 u8 perf_recursion[PERF_NR_CONTEXTS];
1294 struct perf_event_context *perf_event_ctxp;
1295 struct mutex perf_event_mutex;
1296 struct list_head perf_event_list;
1297 #endif
1298 #ifdef CONFIG_DEBUG_PREEMPT
1299 unsigned long preempt_disable_ip;
1300 #endif
1301 #ifdef CONFIG_NUMA
1302 /* Protected by alloc_lock: */
1303 struct mempolicy *mempolicy;
1304 short il_prev;
1305 u8 il_weight;
1306 short pref_node_fork;
1307 #endif
1308 #ifdef CONFIG_NUMA_BALANCING
1309 int numa_scan_seq;
1310 unsigned int numa_scan_period;
1311 unsigned int numa_scan_period_max;
1312 int numa_preferred_nid;
1313 unsigned long numa_migrate_retry;
1314 /* Migration stamp: */
1315 u64 node_stamp;
1316 u64 last_task_numa_placement;
1317 u64 last_sum_exec_runtime;
1318 struct callback_head numa_work;
1319
1320 /*
1321 * This pointer is only modified for current in syscall and
1322 * pagefault context (and for tasks being destroyed), so it can be read
1323 * from any of the following contexts:
1324 * - RCU read-side critical section
1325 * - current->numa_group from everywhere
1326 * - task's runqueue locked, task not running
1327 */
1328 struct numa_group __rcu *numa_group;
1329
1330 /*
1331 * numa_faults is an array split into four regions:
1332 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1333 * in this precise order.
1334 *
1335 * faults_memory: Exponential decaying average of faults on a per-node
1336 * basis. Scheduling placement decisions are made based on these
1337 * counts. The values remain static for the duration of a PTE scan.
1338 * faults_cpu: Track the nodes the process was running on when a NUMA
1339 * hinting fault was incurred.
1340 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1341 * during the current scan window. When the scan completes, the counts
1342 * in faults_memory and faults_cpu decay and these values are copied.
1343 */
1344 unsigned long *numa_faults;
1345 unsigned long total_numa_faults;
1346
1347 /*
1348 * numa_faults_locality tracks if faults recorded during the last
1349 * scan window were remote/local or failed to migrate. The task scan
1350 * period is adapted based on the locality of the faults with different
1351 * weights depending on whether they were shared or private faults
1352 */
1353 unsigned long numa_faults_locality[3];
1354
1355 unsigned long numa_pages_migrated;
1356 #endif /* CONFIG_NUMA_BALANCING */
1357
1358 #ifdef CONFIG_RSEQ
1359 struct rseq __user *rseq;
1360 u32 rseq_len;
1361 u32 rseq_sig;
1362 /*
1363 * RmW on rseq_event_mask must be performed atomically
1364 * with respect to preemption.
1365 */
1366 unsigned long rseq_event_mask;
1367 #endif
1368
1369 #ifdef CONFIG_SCHED_MM_CID
1370 int mm_cid; /* Current cid in mm */
1371 int last_mm_cid; /* Most recent cid in mm */
1372 int migrate_from_cpu;
1373 int mm_cid_active; /* Whether cid bitmap is active */
1374 struct callback_head cid_work;
1375 #endif
1376
1377 struct tlbflush_unmap_batch tlb_ubc;
1378
1379 /* Cache last used pipe for splice(): */
1380 struct pipe_inode_info *splice_pipe;
1381
1382 struct page_frag task_frag;
1383
1384 #ifdef CONFIG_TASK_DELAY_ACCT
1385 struct task_delay_info *delays;
1386 #endif
1387
1388 #ifdef CONFIG_FAULT_INJECTION
1389 int make_it_fail;
1390 unsigned int fail_nth;
1391 #endif
1392 /*
1393 * When (nr_dirtied >= nr_dirtied_pause), it's time to call
1394 * balance_dirty_pages() for a dirty throttling pause:
1395 */
1396 int nr_dirtied;
1397 int nr_dirtied_pause;
1398 /* Start of a write-and-pause period: */
1399 unsigned long dirty_paused_when;
1400
1401 #ifdef CONFIG_LATENCYTOP
1402 int latency_record_count;
1403 struct latency_record latency_record[LT_SAVECOUNT];
1404 #endif
1405 /*
1406 * Time slack values; these are used to round up poll() and
1407 * select() etc timeout values. These are in nanoseconds.
1408 */
1409 u64 timer_slack_ns;
1410 u64 default_timer_slack_ns;
1411
1412 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
1413 unsigned int kasan_depth;
1414 #endif
1415
1416 #ifdef CONFIG_KCSAN
1417 struct kcsan_ctx kcsan_ctx;
1418 #ifdef CONFIG_TRACE_IRQFLAGS
1419 struct irqtrace_events kcsan_save_irqtrace;
1420 #endif
1421 #ifdef CONFIG_KCSAN_WEAK_MEMORY
1422 int kcsan_stack_depth;
1423 #endif
1424 #endif
1425
1426 #ifdef CONFIG_KMSAN
1427 struct kmsan_ctx kmsan_ctx;
1428 #endif
1429
1430 #if IS_ENABLED(CONFIG_KUNIT)
1431 struct kunit *kunit_test;
1432 #endif
1433
1434 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1435 /* Index of current stored address in ret_stack: */
1436 int curr_ret_stack;
1437 int curr_ret_depth;
1438
1439 /* Stack of return addresses for return function tracing: */
1440 unsigned long *ret_stack;
1441
1442 /* Timestamp for last schedule: */
1443 unsigned long long ftrace_timestamp;
1444
1445 /*
1446 * Number of functions that haven't been traced
1447 * because of depth overrun:
1448 */
1449 atomic_t trace_overrun;
1450
1451 /* Pause tracing: */
1452 atomic_t tracing_graph_pause;
1453 #endif
1454
1455 #ifdef CONFIG_TRACING
1456 /* Bitmask and counter of trace recursion: */
1457 unsigned long trace_recursion;
1458 #endif /* CONFIG_TRACING */
1459
1460 #ifdef CONFIG_KCOV
1461 /* See kernel/kcov.c for more details. */
1462
1463 /* Coverage collection mode enabled for this task (0 if disabled): */
1464 unsigned int kcov_mode;
1465
1466 /* Size of the kcov_area: */
1467 unsigned int kcov_size;
1468
1469 /* Buffer for coverage collection: */
1470 void *kcov_area;
1471
1472 /* KCOV descriptor wired with this task or NULL: */
1473 struct kcov *kcov;
1474
1475 /* KCOV common handle for remote coverage collection: */
1476 u64 kcov_handle;
1477
1478 /* KCOV sequence number: */
1479 int kcov_sequence;
1480
1481 /* Collect coverage from softirq context: */
1482 unsigned int kcov_softirq;
1483 #endif
1484
1485 #ifdef CONFIG_MEMCG_V1
1486 struct mem_cgroup *memcg_in_oom;
1487 #endif
1488
1489 #ifdef CONFIG_MEMCG
1490 /* Number of pages to reclaim on returning to userland: */
1491 unsigned int memcg_nr_pages_over_high;
1492
1493 /* Used by memcontrol for targeted memcg charge: */
1494 struct mem_cgroup *active_memcg;
1495
1496 /* Cache for current->cgroups->memcg->objcg lookups: */
1497 struct obj_cgroup *objcg;
1498 #endif
1499
1500 #ifdef CONFIG_BLK_CGROUP
1501 struct gendisk *throttle_disk;
1502 #endif
1503
1504 #ifdef CONFIG_UPROBES
1505 struct uprobe_task *utask;
1506 #endif
1507 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1508 unsigned int sequential_io;
1509 unsigned int sequential_io_avg;
1510 #endif
1511 struct kmap_ctrl kmap_ctrl;
1512 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1513 unsigned long task_state_change;
1514 # ifdef CONFIG_PREEMPT_RT
1515 unsigned long saved_state_change;
1516 # endif
1517 #endif
1518 struct rcu_head rcu;
1519 refcount_t rcu_users;
1520 int pagefault_disabled;
1521 #ifdef CONFIG_MMU
1522 struct task_struct *oom_reaper_list;
1523 struct timer_list oom_reaper_timer;
1524 #endif
1525 #ifdef CONFIG_VMAP_STACK
1526 struct vm_struct *stack_vm_area;
1527 #endif
1528 #ifdef CONFIG_THREAD_INFO_IN_TASK
1529 /* A live task holds one reference: */
1530 refcount_t stack_refcount;
1531 #endif
1532 #ifdef CONFIG_LIVEPATCH
1533 int patch_state;
1534 #endif
1535 #ifdef CONFIG_SECURITY
1536 /* Used by LSM modules for access restriction: */
1537 void *security;
1538 #endif
1539 #ifdef CONFIG_BPF_SYSCALL
1540 /* Used by BPF task local storage */
1541 struct bpf_local_storage __rcu *bpf_storage;
1542 /* Used for BPF run context */
1543 struct bpf_run_ctx *bpf_ctx;
1544 #endif
1545 /* Used by BPF for per-TASK xdp storage */
1546 struct bpf_net_context *bpf_net_context;
1547
1548 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK
1549 unsigned long lowest_stack;
1550 unsigned long prev_lowest_stack;
1551 #endif
1552
1553 #ifdef CONFIG_X86_MCE
1554 void __user *mce_vaddr;
1555 __u64 mce_kflags;
1556 u64 mce_addr;
1557 __u64 mce_ripv : 1,
1558 mce_whole_page : 1,
1559 __mce_reserved : 62;
1560 struct callback_head mce_kill_me;
1561 int mce_count;
1562 #endif
1563
1564 #ifdef CONFIG_KRETPROBES
1565 struct llist_head kretprobe_instances;
1566 #endif
1567 #ifdef CONFIG_RETHOOK
1568 struct llist_head rethooks;
1569 #endif
1570
1571 #ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH
1572 /*
1573 * If L1D flush is supported on mm context switch
1574 * then we use this callback head to queue kill work
1575 * to kill tasks that are not running on SMT disabled
1576 * cores
1577 */
1578 struct callback_head l1d_flush_kill;
1579 #endif
1580
1581 #ifdef CONFIG_RV
1582 /*
1583 * Per-task RV monitor. Nowadays fixed in RV_PER_TASK_MONITORS.
1584 * If we find justification for more monitors, we can think
1585 * about adding more or developing a dynamic method. So far,
1586 * none of these are justified.
1587 */
1588 union rv_task_monitor rv[RV_PER_TASK_MONITORS];
1589 #endif
1590
1591 #ifdef CONFIG_USER_EVENTS
1592 struct user_event_mm *user_event_mm;
1593 #endif
1594
1595 /*
1596 * New fields for task_struct should be added above here, so that
1597 * they are included in the randomized portion of task_struct.
1598 */
1599 randomized_struct_fields_end
1600
1601 /* CPU-specific state of this task: */
1602 struct thread_struct thread;
1603
1604 /*
1605 * WARNING: on x86, 'thread_struct' contains a variable-sized
1606 * structure. It *MUST* be at the end of 'task_struct'.
1607 *
1608 * Do not put anything below here!
1609 */
1610 };
1611
1612 #define TASK_REPORT_IDLE (TASK_REPORT + 1)
1613 #define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1)
1614
__task_state_index(unsigned int tsk_state,unsigned int tsk_exit_state)1615 static inline unsigned int __task_state_index(unsigned int tsk_state,
1616 unsigned int tsk_exit_state)
1617 {
1618 unsigned int state = (tsk_state | tsk_exit_state) & TASK_REPORT;
1619
1620 BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);
1621
1622 if ((tsk_state & TASK_IDLE) == TASK_IDLE)
1623 state = TASK_REPORT_IDLE;
1624
1625 /*
1626 * We're lying here, but rather than expose a completely new task state
1627 * to userspace, we can make this appear as if the task has gone through
1628 * a regular rt_mutex_lock() call.
1629 */
1630 if (tsk_state & TASK_RTLOCK_WAIT)
1631 state = TASK_UNINTERRUPTIBLE;
1632
1633 return fls(state);
1634 }
1635
task_state_index(struct task_struct * tsk)1636 static inline unsigned int task_state_index(struct task_struct *tsk)
1637 {
1638 return __task_state_index(READ_ONCE(tsk->__state), tsk->exit_state);
1639 }
1640
task_index_to_char(unsigned int state)1641 static inline char task_index_to_char(unsigned int state)
1642 {
1643 static const char state_char[] = "RSDTtXZPI";
1644
1645 BUILD_BUG_ON(TASK_REPORT_MAX * 2 != 1 << (sizeof(state_char) - 1));
1646
1647 return state_char[state];
1648 }
1649
task_state_to_char(struct task_struct * tsk)1650 static inline char task_state_to_char(struct task_struct *tsk)
1651 {
1652 return task_index_to_char(task_state_index(tsk));
1653 }
1654
1655 extern struct pid *cad_pid;
1656
1657 /*
1658 * Per process flags
1659 */
1660 #define PF_VCPU 0x00000001 /* I'm a virtual CPU */
1661 #define PF_IDLE 0x00000002 /* I am an IDLE thread */
1662 #define PF_EXITING 0x00000004 /* Getting shut down */
1663 #define PF_POSTCOREDUMP 0x00000008 /* Coredumps should ignore this task */
1664 #define PF_IO_WORKER 0x00000010 /* Task is an IO worker */
1665 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */
1666 #define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */
1667 #define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */
1668 #define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */
1669 #define PF_DUMPCORE 0x00000200 /* Dumped core */
1670 #define PF_SIGNALED 0x00000400 /* Killed by a signal */
1671 #define PF_MEMALLOC 0x00000800 /* Allocating memory to free memory. See memalloc_noreclaim_save() */
1672 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */
1673 #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */
1674 #define PF_USER_WORKER 0x00004000 /* Kernel thread cloned from userspace thread */
1675 #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */
1676 #define PF__HOLE__00010000 0x00010000
1677 #define PF_KSWAPD 0x00020000 /* I am kswapd */
1678 #define PF_MEMALLOC_NOFS 0x00040000 /* All allocations inherit GFP_NOFS. See memalloc_nfs_save() */
1679 #define PF_MEMALLOC_NOIO 0x00080000 /* All allocations inherit GFP_NOIO. See memalloc_noio_save() */
1680 #define PF_LOCAL_THROTTLE 0x00100000 /* Throttle writes only against the bdi I write to,
1681 * I am cleaning dirty pages from some other bdi. */
1682 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */
1683 #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */
1684 #define PF__HOLE__00800000 0x00800000
1685 #define PF__HOLE__01000000 0x01000000
1686 #define PF__HOLE__02000000 0x02000000
1687 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */
1688 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
1689 #define PF_MEMALLOC_PIN 0x10000000 /* Allocations constrained to zones which allow long term pinning.
1690 * See memalloc_pin_save() */
1691 #define PF_BLOCK_TS 0x20000000 /* plug has ts that needs updating */
1692 #define PF__HOLE__40000000 0x40000000
1693 #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */
1694
1695 /*
1696 * Only the _current_ task can read/write to tsk->flags, but other
1697 * tasks can access tsk->flags in readonly mode for example
1698 * with tsk_used_math (like during threaded core dumping).
1699 * There is however an exception to this rule during ptrace
1700 * or during fork: the ptracer task is allowed to write to the
1701 * child->flags of its traced child (same goes for fork, the parent
1702 * can write to the child->flags), because we're guaranteed the
1703 * child is not running and in turn not changing child->flags
1704 * at the same time the parent does it.
1705 */
1706 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1707 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1708 #define clear_used_math() clear_stopped_child_used_math(current)
1709 #define set_used_math() set_stopped_child_used_math(current)
1710
1711 #define conditional_stopped_child_used_math(condition, child) \
1712 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1713
1714 #define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current)
1715
1716 #define copy_to_stopped_child_used_math(child) \
1717 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1718
1719 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1720 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1721 #define used_math() tsk_used_math(current)
1722
is_percpu_thread(void)1723 static __always_inline bool is_percpu_thread(void)
1724 {
1725 #ifdef CONFIG_SMP
1726 return (current->flags & PF_NO_SETAFFINITY) &&
1727 (current->nr_cpus_allowed == 1);
1728 #else
1729 return true;
1730 #endif
1731 }
1732
1733 /* Per-process atomic flags. */
1734 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */
1735 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */
1736 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */
1737 #define PFA_SPEC_SSB_DISABLE 3 /* Speculative Store Bypass disabled */
1738 #define PFA_SPEC_SSB_FORCE_DISABLE 4 /* Speculative Store Bypass force disabled*/
1739 #define PFA_SPEC_IB_DISABLE 5 /* Indirect branch speculation restricted */
1740 #define PFA_SPEC_IB_FORCE_DISABLE 6 /* Indirect branch speculation permanently restricted */
1741 #define PFA_SPEC_SSB_NOEXEC 7 /* Speculative Store Bypass clear on execve() */
1742
1743 #define TASK_PFA_TEST(name, func) \
1744 static inline bool task_##func(struct task_struct *p) \
1745 { return test_bit(PFA_##name, &p->atomic_flags); }
1746
1747 #define TASK_PFA_SET(name, func) \
1748 static inline void task_set_##func(struct task_struct *p) \
1749 { set_bit(PFA_##name, &p->atomic_flags); }
1750
1751 #define TASK_PFA_CLEAR(name, func) \
1752 static inline void task_clear_##func(struct task_struct *p) \
1753 { clear_bit(PFA_##name, &p->atomic_flags); }
1754
TASK_PFA_TEST(NO_NEW_PRIVS,no_new_privs)1755 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1756 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1757
1758 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1759 TASK_PFA_SET(SPREAD_PAGE, spread_page)
1760 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
1761
1762 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
1763 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
1764 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1765
1766 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable)
1767 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable)
1768 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable)
1769
1770 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1771 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1772 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1773
1774 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1775 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1776
1777 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable)
1778 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable)
1779 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable)
1780
1781 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1782 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1783
1784 static inline void
1785 current_restore_flags(unsigned long orig_flags, unsigned long flags)
1786 {
1787 current->flags &= ~flags;
1788 current->flags |= orig_flags & flags;
1789 }
1790
1791 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
1792 extern int task_can_attach(struct task_struct *p);
1793 extern int dl_bw_alloc(int cpu, u64 dl_bw);
1794 extern void dl_bw_free(int cpu, u64 dl_bw);
1795 #ifdef CONFIG_SMP
1796
1797 /* do_set_cpus_allowed() - consider using set_cpus_allowed_ptr() instead */
1798 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask);
1799
1800 /**
1801 * set_cpus_allowed_ptr - set CPU affinity mask of a task
1802 * @p: the task
1803 * @new_mask: CPU affinity mask
1804 *
1805 * Return: zero if successful, or a negative error code
1806 */
1807 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
1808 extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node);
1809 extern void release_user_cpus_ptr(struct task_struct *p);
1810 extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask);
1811 extern void force_compatible_cpus_allowed_ptr(struct task_struct *p);
1812 extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p);
1813 #else
do_set_cpus_allowed(struct task_struct * p,const struct cpumask * new_mask)1814 static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
1815 {
1816 }
set_cpus_allowed_ptr(struct task_struct * p,const struct cpumask * new_mask)1817 static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
1818 {
1819 /* Opencoded cpumask_test_cpu(0, new_mask) to avoid dependency on cpumask.h */
1820 if ((*cpumask_bits(new_mask) & 1) == 0)
1821 return -EINVAL;
1822 return 0;
1823 }
dup_user_cpus_ptr(struct task_struct * dst,struct task_struct * src,int node)1824 static inline int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node)
1825 {
1826 if (src->user_cpus_ptr)
1827 return -EINVAL;
1828 return 0;
1829 }
release_user_cpus_ptr(struct task_struct * p)1830 static inline void release_user_cpus_ptr(struct task_struct *p)
1831 {
1832 WARN_ON(p->user_cpus_ptr);
1833 }
1834
dl_task_check_affinity(struct task_struct * p,const struct cpumask * mask)1835 static inline int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask)
1836 {
1837 return 0;
1838 }
1839 #endif
1840
1841 extern int yield_to(struct task_struct *p, bool preempt);
1842 extern void set_user_nice(struct task_struct *p, long nice);
1843 extern int task_prio(const struct task_struct *p);
1844
1845 /**
1846 * task_nice - return the nice value of a given task.
1847 * @p: the task in question.
1848 *
1849 * Return: The nice value [ -20 ... 0 ... 19 ].
1850 */
task_nice(const struct task_struct * p)1851 static inline int task_nice(const struct task_struct *p)
1852 {
1853 return PRIO_TO_NICE((p)->static_prio);
1854 }
1855
1856 extern int can_nice(const struct task_struct *p, const int nice);
1857 extern int task_curr(const struct task_struct *p);
1858 extern int idle_cpu(int cpu);
1859 extern int available_idle_cpu(int cpu);
1860 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
1861 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
1862 extern void sched_set_fifo(struct task_struct *p);
1863 extern void sched_set_fifo_low(struct task_struct *p);
1864 extern void sched_set_normal(struct task_struct *p, int nice);
1865 extern int sched_setattr(struct task_struct *, const struct sched_attr *);
1866 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *);
1867 extern struct task_struct *idle_task(int cpu);
1868
1869 /**
1870 * is_idle_task - is the specified task an idle task?
1871 * @p: the task in question.
1872 *
1873 * Return: 1 if @p is an idle task. 0 otherwise.
1874 */
is_idle_task(const struct task_struct * p)1875 static __always_inline bool is_idle_task(const struct task_struct *p)
1876 {
1877 return !!(p->flags & PF_IDLE);
1878 }
1879
1880 extern struct task_struct *curr_task(int cpu);
1881 extern void ia64_set_curr_task(int cpu, struct task_struct *p);
1882
1883 void yield(void);
1884
1885 union thread_union {
1886 struct task_struct task;
1887 #ifndef CONFIG_THREAD_INFO_IN_TASK
1888 struct thread_info thread_info;
1889 #endif
1890 unsigned long stack[THREAD_SIZE/sizeof(long)];
1891 };
1892
1893 #ifndef CONFIG_THREAD_INFO_IN_TASK
1894 extern struct thread_info init_thread_info;
1895 #endif
1896
1897 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];
1898
1899 #ifdef CONFIG_THREAD_INFO_IN_TASK
1900 # define task_thread_info(task) (&(task)->thread_info)
1901 #elif !defined(__HAVE_THREAD_FUNCTIONS)
1902 # define task_thread_info(task) ((struct thread_info *)(task)->stack)
1903 #endif
1904
1905 /*
1906 * find a task by one of its numerical ids
1907 *
1908 * find_task_by_pid_ns():
1909 * finds a task by its pid in the specified namespace
1910 * find_task_by_vpid():
1911 * finds a task by its virtual pid
1912 *
1913 * see also find_vpid() etc in include/linux/pid.h
1914 */
1915
1916 extern struct task_struct *find_task_by_vpid(pid_t nr);
1917 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns);
1918
1919 /*
1920 * find a task by its virtual pid and get the task struct
1921 */
1922 extern struct task_struct *find_get_task_by_vpid(pid_t nr);
1923
1924 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1925 extern int wake_up_process(struct task_struct *tsk);
1926 extern void wake_up_new_task(struct task_struct *tsk);
1927
1928 #ifdef CONFIG_SMP
1929 extern void kick_process(struct task_struct *tsk);
1930 #else
kick_process(struct task_struct * tsk)1931 static inline void kick_process(struct task_struct *tsk) { }
1932 #endif
1933
1934 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
1935
set_task_comm(struct task_struct * tsk,const char * from)1936 static inline void set_task_comm(struct task_struct *tsk, const char *from)
1937 {
1938 __set_task_comm(tsk, from, false);
1939 }
1940
1941 extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk);
1942 #define get_task_comm(buf, tsk) ({ \
1943 BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN); \
1944 __get_task_comm(buf, sizeof(buf), tsk); \
1945 })
1946
1947 #ifdef CONFIG_SMP
scheduler_ipi(void)1948 static __always_inline void scheduler_ipi(void)
1949 {
1950 /*
1951 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting
1952 * TIF_NEED_RESCHED remotely (for the first time) will also send
1953 * this IPI.
1954 */
1955 preempt_fold_need_resched();
1956 }
1957 #else
scheduler_ipi(void)1958 static inline void scheduler_ipi(void) { }
1959 #endif
1960
1961 extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state);
1962
1963 /*
1964 * Set thread flags in other task's structures.
1965 * See asm/thread_info.h for TIF_xxxx flags available:
1966 */
set_tsk_thread_flag(struct task_struct * tsk,int flag)1967 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1968 {
1969 set_ti_thread_flag(task_thread_info(tsk), flag);
1970 }
1971
clear_tsk_thread_flag(struct task_struct * tsk,int flag)1972 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1973 {
1974 clear_ti_thread_flag(task_thread_info(tsk), flag);
1975 }
1976
update_tsk_thread_flag(struct task_struct * tsk,int flag,bool value)1977 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag,
1978 bool value)
1979 {
1980 update_ti_thread_flag(task_thread_info(tsk), flag, value);
1981 }
1982
test_and_set_tsk_thread_flag(struct task_struct * tsk,int flag)1983 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1984 {
1985 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1986 }
1987
test_and_clear_tsk_thread_flag(struct task_struct * tsk,int flag)1988 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1989 {
1990 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1991 }
1992
test_tsk_thread_flag(struct task_struct * tsk,int flag)1993 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1994 {
1995 return test_ti_thread_flag(task_thread_info(tsk), flag);
1996 }
1997
set_tsk_need_resched(struct task_struct * tsk)1998 static inline void set_tsk_need_resched(struct task_struct *tsk)
1999 {
2000 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2001 }
2002
clear_tsk_need_resched(struct task_struct * tsk)2003 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2004 {
2005 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2006 }
2007
test_tsk_need_resched(struct task_struct * tsk)2008 static inline int test_tsk_need_resched(struct task_struct *tsk)
2009 {
2010 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2011 }
2012
2013 /*
2014 * cond_resched() and cond_resched_lock(): latency reduction via
2015 * explicit rescheduling in places that are safe. The return
2016 * value indicates whether a reschedule was done in fact.
2017 * cond_resched_lock() will drop the spinlock before scheduling,
2018 */
2019 #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC)
2020 extern int __cond_resched(void);
2021
2022 #if defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL)
2023
2024 void sched_dynamic_klp_enable(void);
2025 void sched_dynamic_klp_disable(void);
2026
2027 DECLARE_STATIC_CALL(cond_resched, __cond_resched);
2028
_cond_resched(void)2029 static __always_inline int _cond_resched(void)
2030 {
2031 return static_call_mod(cond_resched)();
2032 }
2033
2034 #elif defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY)
2035
2036 extern int dynamic_cond_resched(void);
2037
_cond_resched(void)2038 static __always_inline int _cond_resched(void)
2039 {
2040 return dynamic_cond_resched();
2041 }
2042
2043 #else /* !CONFIG_PREEMPTION */
2044
_cond_resched(void)2045 static inline int _cond_resched(void)
2046 {
2047 klp_sched_try_switch();
2048 return __cond_resched();
2049 }
2050
2051 #endif /* PREEMPT_DYNAMIC && CONFIG_HAVE_PREEMPT_DYNAMIC_CALL */
2052
2053 #else /* CONFIG_PREEMPTION && !CONFIG_PREEMPT_DYNAMIC */
2054
_cond_resched(void)2055 static inline int _cond_resched(void)
2056 {
2057 klp_sched_try_switch();
2058 return 0;
2059 }
2060
2061 #endif /* !CONFIG_PREEMPTION || CONFIG_PREEMPT_DYNAMIC */
2062
2063 #define cond_resched() ({ \
2064 __might_resched(__FILE__, __LINE__, 0); \
2065 _cond_resched(); \
2066 })
2067
2068 extern int __cond_resched_lock(spinlock_t *lock);
2069 extern int __cond_resched_rwlock_read(rwlock_t *lock);
2070 extern int __cond_resched_rwlock_write(rwlock_t *lock);
2071
2072 #define MIGHT_RESCHED_RCU_SHIFT 8
2073 #define MIGHT_RESCHED_PREEMPT_MASK ((1U << MIGHT_RESCHED_RCU_SHIFT) - 1)
2074
2075 #ifndef CONFIG_PREEMPT_RT
2076 /*
2077 * Non RT kernels have an elevated preempt count due to the held lock,
2078 * but are not allowed to be inside a RCU read side critical section
2079 */
2080 # define PREEMPT_LOCK_RESCHED_OFFSETS PREEMPT_LOCK_OFFSET
2081 #else
2082 /*
2083 * spin/rw_lock() on RT implies rcu_read_lock(). The might_sleep() check in
2084 * cond_resched*lock() has to take that into account because it checks for
2085 * preempt_count() and rcu_preempt_depth().
2086 */
2087 # define PREEMPT_LOCK_RESCHED_OFFSETS \
2088 (PREEMPT_LOCK_OFFSET + (1U << MIGHT_RESCHED_RCU_SHIFT))
2089 #endif
2090
2091 #define cond_resched_lock(lock) ({ \
2092 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \
2093 __cond_resched_lock(lock); \
2094 })
2095
2096 #define cond_resched_rwlock_read(lock) ({ \
2097 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \
2098 __cond_resched_rwlock_read(lock); \
2099 })
2100
2101 #define cond_resched_rwlock_write(lock) ({ \
2102 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \
2103 __cond_resched_rwlock_write(lock); \
2104 })
2105
need_resched(void)2106 static __always_inline bool need_resched(void)
2107 {
2108 return unlikely(tif_need_resched());
2109 }
2110
2111 /*
2112 * Wrappers for p->thread_info->cpu access. No-op on UP.
2113 */
2114 #ifdef CONFIG_SMP
2115
task_cpu(const struct task_struct * p)2116 static inline unsigned int task_cpu(const struct task_struct *p)
2117 {
2118 return READ_ONCE(task_thread_info(p)->cpu);
2119 }
2120
2121 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2122
2123 #else
2124
task_cpu(const struct task_struct * p)2125 static inline unsigned int task_cpu(const struct task_struct *p)
2126 {
2127 return 0;
2128 }
2129
set_task_cpu(struct task_struct * p,unsigned int cpu)2130 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2131 {
2132 }
2133
2134 #endif /* CONFIG_SMP */
2135
task_is_runnable(struct task_struct * p)2136 static inline bool task_is_runnable(struct task_struct *p)
2137 {
2138 return p->on_rq && !p->se.sched_delayed;
2139 }
2140
2141 extern bool sched_task_on_rq(struct task_struct *p);
2142 extern unsigned long get_wchan(struct task_struct *p);
2143 extern struct task_struct *cpu_curr_snapshot(int cpu);
2144
2145 #include <linux/spinlock.h>
2146
2147 /*
2148 * In order to reduce various lock holder preemption latencies provide an
2149 * interface to see if a vCPU is currently running or not.
2150 *
2151 * This allows us to terminate optimistic spin loops and block, analogous to
2152 * the native optimistic spin heuristic of testing if the lock owner task is
2153 * running or not.
2154 */
2155 #ifndef vcpu_is_preempted
vcpu_is_preempted(int cpu)2156 static inline bool vcpu_is_preempted(int cpu)
2157 {
2158 return false;
2159 }
2160 #endif
2161
2162 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2163 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2164
2165 #ifndef TASK_SIZE_OF
2166 #define TASK_SIZE_OF(tsk) TASK_SIZE
2167 #endif
2168
2169 #ifdef CONFIG_SMP
owner_on_cpu(struct task_struct * owner)2170 static inline bool owner_on_cpu(struct task_struct *owner)
2171 {
2172 /*
2173 * As lock holder preemption issue, we both skip spinning if
2174 * task is not on cpu or its cpu is preempted
2175 */
2176 return READ_ONCE(owner->on_cpu) && !vcpu_is_preempted(task_cpu(owner));
2177 }
2178
2179 /* Returns effective CPU energy utilization, as seen by the scheduler */
2180 unsigned long sched_cpu_util(int cpu);
2181 #endif /* CONFIG_SMP */
2182
2183 #ifdef CONFIG_SCHED_CORE
2184 extern void sched_core_free(struct task_struct *tsk);
2185 extern void sched_core_fork(struct task_struct *p);
2186 extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type,
2187 unsigned long uaddr);
2188 extern int sched_core_idle_cpu(int cpu);
2189 #else
sched_core_free(struct task_struct * tsk)2190 static inline void sched_core_free(struct task_struct *tsk) { }
sched_core_fork(struct task_struct * p)2191 static inline void sched_core_fork(struct task_struct *p) { }
sched_core_idle_cpu(int cpu)2192 static inline int sched_core_idle_cpu(int cpu) { return idle_cpu(cpu); }
2193 #endif
2194
2195 extern void sched_set_stop_task(int cpu, struct task_struct *stop);
2196
2197 #ifdef CONFIG_MEM_ALLOC_PROFILING
alloc_tag_save(struct alloc_tag * tag)2198 static __always_inline struct alloc_tag *alloc_tag_save(struct alloc_tag *tag)
2199 {
2200 swap(current->alloc_tag, tag);
2201 return tag;
2202 }
2203
alloc_tag_restore(struct alloc_tag * tag,struct alloc_tag * old)2204 static __always_inline void alloc_tag_restore(struct alloc_tag *tag, struct alloc_tag *old)
2205 {
2206 #ifdef CONFIG_MEM_ALLOC_PROFILING_DEBUG
2207 WARN(current->alloc_tag != tag, "current->alloc_tag was changed:\n");
2208 #endif
2209 current->alloc_tag = old;
2210 }
2211 #else
2212 #define alloc_tag_save(_tag) NULL
2213 #define alloc_tag_restore(_tag, _old) do {} while (0)
2214 #endif
2215
2216 #endif
2217