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