xref: /linux/include/linux/sched.h (revision 71e2f4dd5a65bd8dbca0b77661e75eea471168f8)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_SCHED_H
3 #define _LINUX_SCHED_H
4 
5 /*
6  * Define 'struct task_struct' and provide the main scheduler
7  * APIs (schedule(), wakeup variants, etc.)
8  */
9 
10 #include <uapi/linux/sched.h>
11 
12 #include <asm/current.h>
13 
14 #include <linux/pid.h>
15 #include <linux/sem.h>
16 #include <linux/shm.h>
17 #include <linux/kcov.h>
18 #include <linux/mutex.h>
19 #include <linux/plist.h>
20 #include <linux/hrtimer.h>
21 #include <linux/seccomp.h>
22 #include <linux/nodemask.h>
23 #include <linux/rcupdate.h>
24 #include <linux/refcount.h>
25 #include <linux/resource.h>
26 #include <linux/latencytop.h>
27 #include <linux/sched/prio.h>
28 #include <linux/sched/types.h>
29 #include <linux/signal_types.h>
30 #include <linux/mm_types_task.h>
31 #include <linux/task_io_accounting.h>
32 #include <linux/posix-timers.h>
33 #include <linux/rseq.h>
34 
35 /* task_struct member predeclarations (sorted alphabetically): */
36 struct audit_context;
37 struct backing_dev_info;
38 struct bio_list;
39 struct blk_plug;
40 struct capture_control;
41 struct cfs_rq;
42 struct fs_struct;
43 struct futex_pi_state;
44 struct io_context;
45 struct mempolicy;
46 struct nameidata;
47 struct nsproxy;
48 struct perf_event_context;
49 struct pid_namespace;
50 struct pipe_inode_info;
51 struct rcu_node;
52 struct reclaim_state;
53 struct robust_list_head;
54 struct root_domain;
55 struct rq;
56 struct sched_attr;
57 struct sched_param;
58 struct seq_file;
59 struct sighand_struct;
60 struct signal_struct;
61 struct task_delay_info;
62 struct task_group;
63 
64 /*
65  * Task state bitmask. NOTE! These bits are also
66  * encoded in fs/proc/array.c: get_task_state().
67  *
68  * We have two separate sets of flags: task->state
69  * is about runnability, while task->exit_state are
70  * about the task exiting. Confusing, but this way
71  * modifying one set can't modify the other one by
72  * mistake.
73  */
74 
75 /* Used in tsk->state: */
76 #define TASK_RUNNING			0x0000
77 #define TASK_INTERRUPTIBLE		0x0001
78 #define TASK_UNINTERRUPTIBLE		0x0002
79 #define __TASK_STOPPED			0x0004
80 #define __TASK_TRACED			0x0008
81 /* Used in tsk->exit_state: */
82 #define EXIT_DEAD			0x0010
83 #define EXIT_ZOMBIE			0x0020
84 #define EXIT_TRACE			(EXIT_ZOMBIE | EXIT_DEAD)
85 /* Used in tsk->state again: */
86 #define TASK_PARKED			0x0040
87 #define TASK_DEAD			0x0080
88 #define TASK_WAKEKILL			0x0100
89 #define TASK_WAKING			0x0200
90 #define TASK_NOLOAD			0x0400
91 #define TASK_NEW			0x0800
92 #define TASK_STATE_MAX			0x1000
93 
94 /* Convenience macros for the sake of set_current_state: */
95 #define TASK_KILLABLE			(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
96 #define TASK_STOPPED			(TASK_WAKEKILL | __TASK_STOPPED)
97 #define TASK_TRACED			(TASK_WAKEKILL | __TASK_TRACED)
98 
99 #define TASK_IDLE			(TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
100 
101 /* Convenience macros for the sake of wake_up(): */
102 #define TASK_NORMAL			(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
103 
104 /* get_task_state(): */
105 #define TASK_REPORT			(TASK_RUNNING | TASK_INTERRUPTIBLE | \
106 					 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
107 					 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \
108 					 TASK_PARKED)
109 
110 #define task_is_traced(task)		((task->state & __TASK_TRACED) != 0)
111 
112 #define task_is_stopped(task)		((task->state & __TASK_STOPPED) != 0)
113 
114 #define task_is_stopped_or_traced(task)	((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
115 
116 #define task_contributes_to_load(task)	((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
117 					 (task->flags & PF_FROZEN) == 0 && \
118 					 (task->state & TASK_NOLOAD) == 0)
119 
120 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
121 
122 /*
123  * Special states are those that do not use the normal wait-loop pattern. See
124  * the comment with set_special_state().
125  */
126 #define is_special_task_state(state)				\
127 	((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | TASK_DEAD))
128 
129 #define __set_current_state(state_value)			\
130 	do {							\
131 		WARN_ON_ONCE(is_special_task_state(state_value));\
132 		current->task_state_change = _THIS_IP_;		\
133 		current->state = (state_value);			\
134 	} while (0)
135 
136 #define set_current_state(state_value)				\
137 	do {							\
138 		WARN_ON_ONCE(is_special_task_state(state_value));\
139 		current->task_state_change = _THIS_IP_;		\
140 		smp_store_mb(current->state, (state_value));	\
141 	} while (0)
142 
143 #define set_special_state(state_value)					\
144 	do {								\
145 		unsigned long flags; /* may shadow */			\
146 		WARN_ON_ONCE(!is_special_task_state(state_value));	\
147 		raw_spin_lock_irqsave(&current->pi_lock, flags);	\
148 		current->task_state_change = _THIS_IP_;			\
149 		current->state = (state_value);				\
150 		raw_spin_unlock_irqrestore(&current->pi_lock, flags);	\
151 	} while (0)
152 #else
153 /*
154  * set_current_state() includes a barrier so that the write of current->state
155  * is correctly serialised wrt the caller's subsequent test of whether to
156  * actually sleep:
157  *
158  *   for (;;) {
159  *	set_current_state(TASK_UNINTERRUPTIBLE);
160  *	if (!need_sleep)
161  *		break;
162  *
163  *	schedule();
164  *   }
165  *   __set_current_state(TASK_RUNNING);
166  *
167  * If the caller does not need such serialisation (because, for instance, the
168  * condition test and condition change and wakeup are under the same lock) then
169  * use __set_current_state().
170  *
171  * The above is typically ordered against the wakeup, which does:
172  *
173  *   need_sleep = false;
174  *   wake_up_state(p, TASK_UNINTERRUPTIBLE);
175  *
176  * where wake_up_state() executes a full memory barrier before accessing the
177  * task state.
178  *
179  * Wakeup will do: if (@state & p->state) p->state = TASK_RUNNING, that is,
180  * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a
181  * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING).
182  *
183  * However, with slightly different timing the wakeup TASK_RUNNING store can
184  * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not
185  * a problem either because that will result in one extra go around the loop
186  * and our @cond test will save the day.
187  *
188  * Also see the comments of try_to_wake_up().
189  */
190 #define __set_current_state(state_value)				\
191 	current->state = (state_value)
192 
193 #define set_current_state(state_value)					\
194 	smp_store_mb(current->state, (state_value))
195 
196 /*
197  * set_special_state() should be used for those states when the blocking task
198  * can not use the regular condition based wait-loop. In that case we must
199  * serialize against wakeups such that any possible in-flight TASK_RUNNING stores
200  * will not collide with our state change.
201  */
202 #define set_special_state(state_value)					\
203 	do {								\
204 		unsigned long flags; /* may shadow */			\
205 		raw_spin_lock_irqsave(&current->pi_lock, flags);	\
206 		current->state = (state_value);				\
207 		raw_spin_unlock_irqrestore(&current->pi_lock, flags);	\
208 	} while (0)
209 
210 #endif
211 
212 /* Task command name length: */
213 #define TASK_COMM_LEN			16
214 
215 extern void scheduler_tick(void);
216 
217 #define	MAX_SCHEDULE_TIMEOUT		LONG_MAX
218 
219 extern long schedule_timeout(long timeout);
220 extern long schedule_timeout_interruptible(long timeout);
221 extern long schedule_timeout_killable(long timeout);
222 extern long schedule_timeout_uninterruptible(long timeout);
223 extern long schedule_timeout_idle(long timeout);
224 asmlinkage void schedule(void);
225 extern void schedule_preempt_disabled(void);
226 
227 extern int __must_check io_schedule_prepare(void);
228 extern void io_schedule_finish(int token);
229 extern long io_schedule_timeout(long timeout);
230 extern void io_schedule(void);
231 
232 /**
233  * struct prev_cputime - snapshot of system and user cputime
234  * @utime: time spent in user mode
235  * @stime: time spent in system mode
236  * @lock: protects the above two fields
237  *
238  * Stores previous user/system time values such that we can guarantee
239  * monotonicity.
240  */
241 struct prev_cputime {
242 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
243 	u64				utime;
244 	u64				stime;
245 	raw_spinlock_t			lock;
246 #endif
247 };
248 
249 enum vtime_state {
250 	/* Task is sleeping or running in a CPU with VTIME inactive: */
251 	VTIME_INACTIVE = 0,
252 	/* Task runs in userspace in a CPU with VTIME active: */
253 	VTIME_USER,
254 	/* Task runs in kernelspace in a CPU with VTIME active: */
255 	VTIME_SYS,
256 };
257 
258 struct vtime {
259 	seqcount_t		seqcount;
260 	unsigned long long	starttime;
261 	enum vtime_state	state;
262 	u64			utime;
263 	u64			stime;
264 	u64			gtime;
265 };
266 
267 /*
268  * Utilization clamp constraints.
269  * @UCLAMP_MIN:	Minimum utilization
270  * @UCLAMP_MAX:	Maximum utilization
271  * @UCLAMP_CNT:	Utilization clamp constraints count
272  */
273 enum uclamp_id {
274 	UCLAMP_MIN = 0,
275 	UCLAMP_MAX,
276 	UCLAMP_CNT
277 };
278 
279 #ifdef CONFIG_SMP
280 extern struct root_domain def_root_domain;
281 extern struct mutex sched_domains_mutex;
282 #endif
283 
284 struct sched_info {
285 #ifdef CONFIG_SCHED_INFO
286 	/* Cumulative counters: */
287 
288 	/* # of times we have run on this CPU: */
289 	unsigned long			pcount;
290 
291 	/* Time spent waiting on a runqueue: */
292 	unsigned long long		run_delay;
293 
294 	/* Timestamps: */
295 
296 	/* When did we last run on a CPU? */
297 	unsigned long long		last_arrival;
298 
299 	/* When were we last queued to run? */
300 	unsigned long long		last_queued;
301 
302 #endif /* CONFIG_SCHED_INFO */
303 };
304 
305 /*
306  * Integer metrics need fixed point arithmetic, e.g., sched/fair
307  * has a few: load, load_avg, util_avg, freq, and capacity.
308  *
309  * We define a basic fixed point arithmetic range, and then formalize
310  * all these metrics based on that basic range.
311  */
312 # define SCHED_FIXEDPOINT_SHIFT		10
313 # define SCHED_FIXEDPOINT_SCALE		(1L << SCHED_FIXEDPOINT_SHIFT)
314 
315 /* Increase resolution of cpu_capacity calculations */
316 # define SCHED_CAPACITY_SHIFT		SCHED_FIXEDPOINT_SHIFT
317 # define SCHED_CAPACITY_SCALE		(1L << SCHED_CAPACITY_SHIFT)
318 
319 struct load_weight {
320 	unsigned long			weight;
321 	u32				inv_weight;
322 };
323 
324 /**
325  * struct util_est - Estimation utilization of FAIR tasks
326  * @enqueued: instantaneous estimated utilization of a task/cpu
327  * @ewma:     the Exponential Weighted Moving Average (EWMA)
328  *            utilization of a task
329  *
330  * Support data structure to track an Exponential Weighted Moving Average
331  * (EWMA) of a FAIR task's utilization. New samples are added to the moving
332  * average each time a task completes an activation. Sample's weight is chosen
333  * so that the EWMA will be relatively insensitive to transient changes to the
334  * task's workload.
335  *
336  * The enqueued attribute has a slightly different meaning for tasks and cpus:
337  * - task:   the task's util_avg at last task dequeue time
338  * - cfs_rq: the sum of util_est.enqueued for each RUNNABLE task on that CPU
339  * Thus, the util_est.enqueued of a task represents the contribution on the
340  * estimated utilization of the CPU where that task is currently enqueued.
341  *
342  * Only for tasks we track a moving average of the past instantaneous
343  * estimated utilization. This allows to absorb sporadic drops in utilization
344  * of an otherwise almost periodic task.
345  */
346 struct util_est {
347 	unsigned int			enqueued;
348 	unsigned int			ewma;
349 #define UTIL_EST_WEIGHT_SHIFT		2
350 } __attribute__((__aligned__(sizeof(u64))));
351 
352 /*
353  * The load_avg/util_avg accumulates an infinite geometric series
354  * (see __update_load_avg() in kernel/sched/fair.c).
355  *
356  * [load_avg definition]
357  *
358  *   load_avg = runnable% * scale_load_down(load)
359  *
360  * where runnable% is the time ratio that a sched_entity is runnable.
361  * For cfs_rq, it is the aggregated load_avg of all runnable and
362  * blocked sched_entities.
363  *
364  * [util_avg definition]
365  *
366  *   util_avg = running% * SCHED_CAPACITY_SCALE
367  *
368  * where running% is the time ratio that a sched_entity is running on
369  * a CPU. For cfs_rq, it is the aggregated util_avg of all runnable
370  * and blocked sched_entities.
371  *
372  * load_avg and util_avg don't direcly factor frequency scaling and CPU
373  * capacity scaling. The scaling is done through the rq_clock_pelt that
374  * is used for computing those signals (see update_rq_clock_pelt())
375  *
376  * N.B., the above ratios (runnable% and running%) themselves are in the
377  * range of [0, 1]. To do fixed point arithmetics, we therefore scale them
378  * to as large a range as necessary. This is for example reflected by
379  * util_avg's SCHED_CAPACITY_SCALE.
380  *
381  * [Overflow issue]
382  *
383  * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
384  * with the highest load (=88761), always runnable on a single cfs_rq,
385  * and should not overflow as the number already hits PID_MAX_LIMIT.
386  *
387  * For all other cases (including 32-bit kernels), struct load_weight's
388  * weight will overflow first before we do, because:
389  *
390  *    Max(load_avg) <= Max(load.weight)
391  *
392  * Then it is the load_weight's responsibility to consider overflow
393  * issues.
394  */
395 struct sched_avg {
396 	u64				last_update_time;
397 	u64				load_sum;
398 	u64				runnable_load_sum;
399 	u32				util_sum;
400 	u32				period_contrib;
401 	unsigned long			load_avg;
402 	unsigned long			runnable_load_avg;
403 	unsigned long			util_avg;
404 	struct util_est			util_est;
405 } ____cacheline_aligned;
406 
407 struct sched_statistics {
408 #ifdef CONFIG_SCHEDSTATS
409 	u64				wait_start;
410 	u64				wait_max;
411 	u64				wait_count;
412 	u64				wait_sum;
413 	u64				iowait_count;
414 	u64				iowait_sum;
415 
416 	u64				sleep_start;
417 	u64				sleep_max;
418 	s64				sum_sleep_runtime;
419 
420 	u64				block_start;
421 	u64				block_max;
422 	u64				exec_max;
423 	u64				slice_max;
424 
425 	u64				nr_migrations_cold;
426 	u64				nr_failed_migrations_affine;
427 	u64				nr_failed_migrations_running;
428 	u64				nr_failed_migrations_hot;
429 	u64				nr_forced_migrations;
430 
431 	u64				nr_wakeups;
432 	u64				nr_wakeups_sync;
433 	u64				nr_wakeups_migrate;
434 	u64				nr_wakeups_local;
435 	u64				nr_wakeups_remote;
436 	u64				nr_wakeups_affine;
437 	u64				nr_wakeups_affine_attempts;
438 	u64				nr_wakeups_passive;
439 	u64				nr_wakeups_idle;
440 #endif
441 };
442 
443 struct sched_entity {
444 	/* For load-balancing: */
445 	struct load_weight		load;
446 	unsigned long			runnable_weight;
447 	struct rb_node			run_node;
448 	struct list_head		group_node;
449 	unsigned int			on_rq;
450 
451 	u64				exec_start;
452 	u64				sum_exec_runtime;
453 	u64				vruntime;
454 	u64				prev_sum_exec_runtime;
455 
456 	u64				nr_migrations;
457 
458 	struct sched_statistics		statistics;
459 
460 #ifdef CONFIG_FAIR_GROUP_SCHED
461 	int				depth;
462 	struct sched_entity		*parent;
463 	/* rq on which this entity is (to be) queued: */
464 	struct cfs_rq			*cfs_rq;
465 	/* rq "owned" by this entity/group: */
466 	struct cfs_rq			*my_q;
467 #endif
468 
469 #ifdef CONFIG_SMP
470 	/*
471 	 * Per entity load average tracking.
472 	 *
473 	 * Put into separate cache line so it does not
474 	 * collide with read-mostly values above.
475 	 */
476 	struct sched_avg		avg;
477 #endif
478 };
479 
480 struct sched_rt_entity {
481 	struct list_head		run_list;
482 	unsigned long			timeout;
483 	unsigned long			watchdog_stamp;
484 	unsigned int			time_slice;
485 	unsigned short			on_rq;
486 	unsigned short			on_list;
487 
488 	struct sched_rt_entity		*back;
489 #ifdef CONFIG_RT_GROUP_SCHED
490 	struct sched_rt_entity		*parent;
491 	/* rq on which this entity is (to be) queued: */
492 	struct rt_rq			*rt_rq;
493 	/* rq "owned" by this entity/group: */
494 	struct rt_rq			*my_q;
495 #endif
496 } __randomize_layout;
497 
498 struct sched_dl_entity {
499 	struct rb_node			rb_node;
500 
501 	/*
502 	 * Original scheduling parameters. Copied here from sched_attr
503 	 * during sched_setattr(), they will remain the same until
504 	 * the next sched_setattr().
505 	 */
506 	u64				dl_runtime;	/* Maximum runtime for each instance	*/
507 	u64				dl_deadline;	/* Relative deadline of each instance	*/
508 	u64				dl_period;	/* Separation of two instances (period) */
509 	u64				dl_bw;		/* dl_runtime / dl_period		*/
510 	u64				dl_density;	/* dl_runtime / dl_deadline		*/
511 
512 	/*
513 	 * Actual scheduling parameters. Initialized with the values above,
514 	 * they are continuously updated during task execution. Note that
515 	 * the remaining runtime could be < 0 in case we are in overrun.
516 	 */
517 	s64				runtime;	/* Remaining runtime for this instance	*/
518 	u64				deadline;	/* Absolute deadline for this instance	*/
519 	unsigned int			flags;		/* Specifying the scheduler behaviour	*/
520 
521 	/*
522 	 * Some bool flags:
523 	 *
524 	 * @dl_throttled tells if we exhausted the runtime. If so, the
525 	 * task has to wait for a replenishment to be performed at the
526 	 * next firing of dl_timer.
527 	 *
528 	 * @dl_boosted tells if we are boosted due to DI. If so we are
529 	 * outside bandwidth enforcement mechanism (but only until we
530 	 * exit the critical section);
531 	 *
532 	 * @dl_yielded tells if task gave up the CPU before consuming
533 	 * all its available runtime during the last job.
534 	 *
535 	 * @dl_non_contending tells if the task is inactive while still
536 	 * contributing to the active utilization. In other words, it
537 	 * indicates if the inactive timer has been armed and its handler
538 	 * has not been executed yet. This flag is useful to avoid race
539 	 * conditions between the inactive timer handler and the wakeup
540 	 * code.
541 	 *
542 	 * @dl_overrun tells if the task asked to be informed about runtime
543 	 * overruns.
544 	 */
545 	unsigned int			dl_throttled      : 1;
546 	unsigned int			dl_boosted        : 1;
547 	unsigned int			dl_yielded        : 1;
548 	unsigned int			dl_non_contending : 1;
549 	unsigned int			dl_overrun	  : 1;
550 
551 	/*
552 	 * Bandwidth enforcement timer. Each -deadline task has its
553 	 * own bandwidth to be enforced, thus we need one timer per task.
554 	 */
555 	struct hrtimer			dl_timer;
556 
557 	/*
558 	 * Inactive timer, responsible for decreasing the active utilization
559 	 * at the "0-lag time". When a -deadline task blocks, it contributes
560 	 * to GRUB's active utilization until the "0-lag time", hence a
561 	 * timer is needed to decrease the active utilization at the correct
562 	 * time.
563 	 */
564 	struct hrtimer inactive_timer;
565 };
566 
567 #ifdef CONFIG_UCLAMP_TASK
568 /* Number of utilization clamp buckets (shorter alias) */
569 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT
570 
571 /*
572  * Utilization clamp for a scheduling entity
573  * @value:		clamp value "assigned" to a se
574  * @bucket_id:		bucket index corresponding to the "assigned" value
575  * @active:		the se is currently refcounted in a rq's bucket
576  * @user_defined:	the requested clamp value comes from user-space
577  *
578  * The bucket_id is the index of the clamp bucket matching the clamp value
579  * which is pre-computed and stored to avoid expensive integer divisions from
580  * the fast path.
581  *
582  * The active bit is set whenever a task has got an "effective" value assigned,
583  * which can be different from the clamp value "requested" from user-space.
584  * This allows to know a task is refcounted in the rq's bucket corresponding
585  * to the "effective" bucket_id.
586  *
587  * The user_defined bit is set whenever a task has got a task-specific clamp
588  * value requested from userspace, i.e. the system defaults apply to this task
589  * just as a restriction. This allows to relax default clamps when a less
590  * restrictive task-specific value has been requested, thus allowing to
591  * implement a "nice" semantic. For example, a task running with a 20%
592  * default boost can still drop its own boosting to 0%.
593  */
594 struct uclamp_se {
595 	unsigned int value		: bits_per(SCHED_CAPACITY_SCALE);
596 	unsigned int bucket_id		: bits_per(UCLAMP_BUCKETS);
597 	unsigned int active		: 1;
598 	unsigned int user_defined	: 1;
599 };
600 #endif /* CONFIG_UCLAMP_TASK */
601 
602 union rcu_special {
603 	struct {
604 		u8			blocked;
605 		u8			need_qs;
606 		u8			exp_hint; /* Hint for performance. */
607 		u8			deferred_qs;
608 	} b; /* Bits. */
609 	u32 s; /* Set of bits. */
610 };
611 
612 enum perf_event_task_context {
613 	perf_invalid_context = -1,
614 	perf_hw_context = 0,
615 	perf_sw_context,
616 	perf_nr_task_contexts,
617 };
618 
619 struct wake_q_node {
620 	struct wake_q_node *next;
621 };
622 
623 struct task_struct {
624 #ifdef CONFIG_THREAD_INFO_IN_TASK
625 	/*
626 	 * For reasons of header soup (see current_thread_info()), this
627 	 * must be the first element of task_struct.
628 	 */
629 	struct thread_info		thread_info;
630 #endif
631 	/* -1 unrunnable, 0 runnable, >0 stopped: */
632 	volatile long			state;
633 
634 	/*
635 	 * This begins the randomizable portion of task_struct. Only
636 	 * scheduling-critical items should be added above here.
637 	 */
638 	randomized_struct_fields_start
639 
640 	void				*stack;
641 	refcount_t			usage;
642 	/* Per task flags (PF_*), defined further below: */
643 	unsigned int			flags;
644 	unsigned int			ptrace;
645 
646 #ifdef CONFIG_SMP
647 	struct llist_node		wake_entry;
648 	int				on_cpu;
649 #ifdef CONFIG_THREAD_INFO_IN_TASK
650 	/* Current CPU: */
651 	unsigned int			cpu;
652 #endif
653 	unsigned int			wakee_flips;
654 	unsigned long			wakee_flip_decay_ts;
655 	struct task_struct		*last_wakee;
656 
657 	/*
658 	 * recent_used_cpu is initially set as the last CPU used by a task
659 	 * that wakes affine another task. Waker/wakee relationships can
660 	 * push tasks around a CPU where each wakeup moves to the next one.
661 	 * Tracking a recently used CPU allows a quick search for a recently
662 	 * used CPU that may be idle.
663 	 */
664 	int				recent_used_cpu;
665 	int				wake_cpu;
666 #endif
667 	int				on_rq;
668 
669 	int				prio;
670 	int				static_prio;
671 	int				normal_prio;
672 	unsigned int			rt_priority;
673 
674 	const struct sched_class	*sched_class;
675 	struct sched_entity		se;
676 	struct sched_rt_entity		rt;
677 #ifdef CONFIG_CGROUP_SCHED
678 	struct task_group		*sched_task_group;
679 #endif
680 	struct sched_dl_entity		dl;
681 
682 #ifdef CONFIG_UCLAMP_TASK
683 	/* Clamp values requested for a scheduling entity */
684 	struct uclamp_se		uclamp_req[UCLAMP_CNT];
685 	/* Effective clamp values used for a scheduling entity */
686 	struct uclamp_se		uclamp[UCLAMP_CNT];
687 #endif
688 
689 #ifdef CONFIG_PREEMPT_NOTIFIERS
690 	/* List of struct preempt_notifier: */
691 	struct hlist_head		preempt_notifiers;
692 #endif
693 
694 #ifdef CONFIG_BLK_DEV_IO_TRACE
695 	unsigned int			btrace_seq;
696 #endif
697 
698 	unsigned int			policy;
699 	int				nr_cpus_allowed;
700 	const cpumask_t			*cpus_ptr;
701 	cpumask_t			cpus_mask;
702 
703 #ifdef CONFIG_PREEMPT_RCU
704 	int				rcu_read_lock_nesting;
705 	union rcu_special		rcu_read_unlock_special;
706 	struct list_head		rcu_node_entry;
707 	struct rcu_node			*rcu_blocked_node;
708 #endif /* #ifdef CONFIG_PREEMPT_RCU */
709 
710 #ifdef CONFIG_TASKS_RCU
711 	unsigned long			rcu_tasks_nvcsw;
712 	u8				rcu_tasks_holdout;
713 	u8				rcu_tasks_idx;
714 	int				rcu_tasks_idle_cpu;
715 	struct list_head		rcu_tasks_holdout_list;
716 #endif /* #ifdef CONFIG_TASKS_RCU */
717 
718 	struct sched_info		sched_info;
719 
720 	struct list_head		tasks;
721 #ifdef CONFIG_SMP
722 	struct plist_node		pushable_tasks;
723 	struct rb_node			pushable_dl_tasks;
724 #endif
725 
726 	struct mm_struct		*mm;
727 	struct mm_struct		*active_mm;
728 
729 	/* Per-thread vma caching: */
730 	struct vmacache			vmacache;
731 
732 #ifdef SPLIT_RSS_COUNTING
733 	struct task_rss_stat		rss_stat;
734 #endif
735 	int				exit_state;
736 	int				exit_code;
737 	int				exit_signal;
738 	/* The signal sent when the parent dies: */
739 	int				pdeath_signal;
740 	/* JOBCTL_*, siglock protected: */
741 	unsigned long			jobctl;
742 
743 	/* Used for emulating ABI behavior of previous Linux versions: */
744 	unsigned int			personality;
745 
746 	/* Scheduler bits, serialized by scheduler locks: */
747 	unsigned			sched_reset_on_fork:1;
748 	unsigned			sched_contributes_to_load:1;
749 	unsigned			sched_migrated:1;
750 	unsigned			sched_remote_wakeup:1;
751 #ifdef CONFIG_PSI
752 	unsigned			sched_psi_wake_requeue:1;
753 #endif
754 
755 	/* Force alignment to the next boundary: */
756 	unsigned			:0;
757 
758 	/* Unserialized, strictly 'current' */
759 
760 	/* Bit to tell LSMs we're in execve(): */
761 	unsigned			in_execve:1;
762 	unsigned			in_iowait:1;
763 #ifndef TIF_RESTORE_SIGMASK
764 	unsigned			restore_sigmask:1;
765 #endif
766 #ifdef CONFIG_MEMCG
767 	unsigned			in_user_fault:1;
768 #endif
769 #ifdef CONFIG_COMPAT_BRK
770 	unsigned			brk_randomized:1;
771 #endif
772 #ifdef CONFIG_CGROUPS
773 	/* disallow userland-initiated cgroup migration */
774 	unsigned			no_cgroup_migration:1;
775 	/* task is frozen/stopped (used by the cgroup freezer) */
776 	unsigned			frozen:1;
777 #endif
778 #ifdef CONFIG_BLK_CGROUP
779 	/* to be used once the psi infrastructure lands upstream. */
780 	unsigned			use_memdelay:1;
781 #endif
782 
783 	unsigned long			atomic_flags; /* Flags requiring atomic access. */
784 
785 	struct restart_block		restart_block;
786 
787 	pid_t				pid;
788 	pid_t				tgid;
789 
790 #ifdef CONFIG_STACKPROTECTOR
791 	/* Canary value for the -fstack-protector GCC feature: */
792 	unsigned long			stack_canary;
793 #endif
794 	/*
795 	 * Pointers to the (original) parent process, youngest child, younger sibling,
796 	 * older sibling, respectively.  (p->father can be replaced with
797 	 * p->real_parent->pid)
798 	 */
799 
800 	/* Real parent process: */
801 	struct task_struct __rcu	*real_parent;
802 
803 	/* Recipient of SIGCHLD, wait4() reports: */
804 	struct task_struct __rcu	*parent;
805 
806 	/*
807 	 * Children/sibling form the list of natural children:
808 	 */
809 	struct list_head		children;
810 	struct list_head		sibling;
811 	struct task_struct		*group_leader;
812 
813 	/*
814 	 * 'ptraced' is the list of tasks this task is using ptrace() on.
815 	 *
816 	 * This includes both natural children and PTRACE_ATTACH targets.
817 	 * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
818 	 */
819 	struct list_head		ptraced;
820 	struct list_head		ptrace_entry;
821 
822 	/* PID/PID hash table linkage. */
823 	struct pid			*thread_pid;
824 	struct hlist_node		pid_links[PIDTYPE_MAX];
825 	struct list_head		thread_group;
826 	struct list_head		thread_node;
827 
828 	struct completion		*vfork_done;
829 
830 	/* CLONE_CHILD_SETTID: */
831 	int __user			*set_child_tid;
832 
833 	/* CLONE_CHILD_CLEARTID: */
834 	int __user			*clear_child_tid;
835 
836 	u64				utime;
837 	u64				stime;
838 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
839 	u64				utimescaled;
840 	u64				stimescaled;
841 #endif
842 	u64				gtime;
843 	struct prev_cputime		prev_cputime;
844 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
845 	struct vtime			vtime;
846 #endif
847 
848 #ifdef CONFIG_NO_HZ_FULL
849 	atomic_t			tick_dep_mask;
850 #endif
851 	/* Context switch counts: */
852 	unsigned long			nvcsw;
853 	unsigned long			nivcsw;
854 
855 	/* Monotonic time in nsecs: */
856 	u64				start_time;
857 
858 	/* Boot based time in nsecs: */
859 	u64				real_start_time;
860 
861 	/* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
862 	unsigned long			min_flt;
863 	unsigned long			maj_flt;
864 
865 	/* Empty if CONFIG_POSIX_CPUTIMERS=n */
866 	struct posix_cputimers		posix_cputimers;
867 
868 	/* Process credentials: */
869 
870 	/* Tracer's credentials at attach: */
871 	const struct cred __rcu		*ptracer_cred;
872 
873 	/* Objective and real subjective task credentials (COW): */
874 	const struct cred __rcu		*real_cred;
875 
876 	/* Effective (overridable) subjective task credentials (COW): */
877 	const struct cred __rcu		*cred;
878 
879 #ifdef CONFIG_KEYS
880 	/* Cached requested key. */
881 	struct key			*cached_requested_key;
882 #endif
883 
884 	/*
885 	 * executable name, excluding path.
886 	 *
887 	 * - normally initialized setup_new_exec()
888 	 * - access it with [gs]et_task_comm()
889 	 * - lock it with task_lock()
890 	 */
891 	char				comm[TASK_COMM_LEN];
892 
893 	struct nameidata		*nameidata;
894 
895 #ifdef CONFIG_SYSVIPC
896 	struct sysv_sem			sysvsem;
897 	struct sysv_shm			sysvshm;
898 #endif
899 #ifdef CONFIG_DETECT_HUNG_TASK
900 	unsigned long			last_switch_count;
901 	unsigned long			last_switch_time;
902 #endif
903 	/* Filesystem information: */
904 	struct fs_struct		*fs;
905 
906 	/* Open file information: */
907 	struct files_struct		*files;
908 
909 	/* Namespaces: */
910 	struct nsproxy			*nsproxy;
911 
912 	/* Signal handlers: */
913 	struct signal_struct		*signal;
914 	struct sighand_struct		*sighand;
915 	sigset_t			blocked;
916 	sigset_t			real_blocked;
917 	/* Restored if set_restore_sigmask() was used: */
918 	sigset_t			saved_sigmask;
919 	struct sigpending		pending;
920 	unsigned long			sas_ss_sp;
921 	size_t				sas_ss_size;
922 	unsigned int			sas_ss_flags;
923 
924 	struct callback_head		*task_works;
925 
926 #ifdef CONFIG_AUDIT
927 #ifdef CONFIG_AUDITSYSCALL
928 	struct audit_context		*audit_context;
929 #endif
930 	kuid_t				loginuid;
931 	unsigned int			sessionid;
932 #endif
933 	struct seccomp			seccomp;
934 
935 	/* Thread group tracking: */
936 	u32				parent_exec_id;
937 	u32				self_exec_id;
938 
939 	/* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
940 	spinlock_t			alloc_lock;
941 
942 	/* Protection of the PI data structures: */
943 	raw_spinlock_t			pi_lock;
944 
945 	struct wake_q_node		wake_q;
946 
947 #ifdef CONFIG_RT_MUTEXES
948 	/* PI waiters blocked on a rt_mutex held by this task: */
949 	struct rb_root_cached		pi_waiters;
950 	/* Updated under owner's pi_lock and rq lock */
951 	struct task_struct		*pi_top_task;
952 	/* Deadlock detection and priority inheritance handling: */
953 	struct rt_mutex_waiter		*pi_blocked_on;
954 #endif
955 
956 #ifdef CONFIG_DEBUG_MUTEXES
957 	/* Mutex deadlock detection: */
958 	struct mutex_waiter		*blocked_on;
959 #endif
960 
961 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
962 	int				non_block_count;
963 #endif
964 
965 #ifdef CONFIG_TRACE_IRQFLAGS
966 	unsigned int			irq_events;
967 	unsigned long			hardirq_enable_ip;
968 	unsigned long			hardirq_disable_ip;
969 	unsigned int			hardirq_enable_event;
970 	unsigned int			hardirq_disable_event;
971 	int				hardirqs_enabled;
972 	int				hardirq_context;
973 	unsigned long			softirq_disable_ip;
974 	unsigned long			softirq_enable_ip;
975 	unsigned int			softirq_disable_event;
976 	unsigned int			softirq_enable_event;
977 	int				softirqs_enabled;
978 	int				softirq_context;
979 #endif
980 
981 #ifdef CONFIG_LOCKDEP
982 # define MAX_LOCK_DEPTH			48UL
983 	u64				curr_chain_key;
984 	int				lockdep_depth;
985 	unsigned int			lockdep_recursion;
986 	struct held_lock		held_locks[MAX_LOCK_DEPTH];
987 #endif
988 
989 #ifdef CONFIG_UBSAN
990 	unsigned int			in_ubsan;
991 #endif
992 
993 	/* Journalling filesystem info: */
994 	void				*journal_info;
995 
996 	/* Stacked block device info: */
997 	struct bio_list			*bio_list;
998 
999 #ifdef CONFIG_BLOCK
1000 	/* Stack plugging: */
1001 	struct blk_plug			*plug;
1002 #endif
1003 
1004 	/* VM state: */
1005 	struct reclaim_state		*reclaim_state;
1006 
1007 	struct backing_dev_info		*backing_dev_info;
1008 
1009 	struct io_context		*io_context;
1010 
1011 #ifdef CONFIG_COMPACTION
1012 	struct capture_control		*capture_control;
1013 #endif
1014 	/* Ptrace state: */
1015 	unsigned long			ptrace_message;
1016 	kernel_siginfo_t		*last_siginfo;
1017 
1018 	struct task_io_accounting	ioac;
1019 #ifdef CONFIG_PSI
1020 	/* Pressure stall state */
1021 	unsigned int			psi_flags;
1022 #endif
1023 #ifdef CONFIG_TASK_XACCT
1024 	/* Accumulated RSS usage: */
1025 	u64				acct_rss_mem1;
1026 	/* Accumulated virtual memory usage: */
1027 	u64				acct_vm_mem1;
1028 	/* stime + utime since last update: */
1029 	u64				acct_timexpd;
1030 #endif
1031 #ifdef CONFIG_CPUSETS
1032 	/* Protected by ->alloc_lock: */
1033 	nodemask_t			mems_allowed;
1034 	/* Seqence number to catch updates: */
1035 	seqcount_t			mems_allowed_seq;
1036 	int				cpuset_mem_spread_rotor;
1037 	int				cpuset_slab_spread_rotor;
1038 #endif
1039 #ifdef CONFIG_CGROUPS
1040 	/* Control Group info protected by css_set_lock: */
1041 	struct css_set __rcu		*cgroups;
1042 	/* cg_list protected by css_set_lock and tsk->alloc_lock: */
1043 	struct list_head		cg_list;
1044 #endif
1045 #ifdef CONFIG_X86_CPU_RESCTRL
1046 	u32				closid;
1047 	u32				rmid;
1048 #endif
1049 #ifdef CONFIG_FUTEX
1050 	struct robust_list_head __user	*robust_list;
1051 #ifdef CONFIG_COMPAT
1052 	struct compat_robust_list_head __user *compat_robust_list;
1053 #endif
1054 	struct list_head		pi_state_list;
1055 	struct futex_pi_state		*pi_state_cache;
1056 #endif
1057 #ifdef CONFIG_PERF_EVENTS
1058 	struct perf_event_context	*perf_event_ctxp[perf_nr_task_contexts];
1059 	struct mutex			perf_event_mutex;
1060 	struct list_head		perf_event_list;
1061 #endif
1062 #ifdef CONFIG_DEBUG_PREEMPT
1063 	unsigned long			preempt_disable_ip;
1064 #endif
1065 #ifdef CONFIG_NUMA
1066 	/* Protected by alloc_lock: */
1067 	struct mempolicy		*mempolicy;
1068 	short				il_prev;
1069 	short				pref_node_fork;
1070 #endif
1071 #ifdef CONFIG_NUMA_BALANCING
1072 	int				numa_scan_seq;
1073 	unsigned int			numa_scan_period;
1074 	unsigned int			numa_scan_period_max;
1075 	int				numa_preferred_nid;
1076 	unsigned long			numa_migrate_retry;
1077 	/* Migration stamp: */
1078 	u64				node_stamp;
1079 	u64				last_task_numa_placement;
1080 	u64				last_sum_exec_runtime;
1081 	struct callback_head		numa_work;
1082 
1083 	/*
1084 	 * This pointer is only modified for current in syscall and
1085 	 * pagefault context (and for tasks being destroyed), so it can be read
1086 	 * from any of the following contexts:
1087 	 *  - RCU read-side critical section
1088 	 *  - current->numa_group from everywhere
1089 	 *  - task's runqueue locked, task not running
1090 	 */
1091 	struct numa_group __rcu		*numa_group;
1092 
1093 	/*
1094 	 * numa_faults is an array split into four regions:
1095 	 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1096 	 * in this precise order.
1097 	 *
1098 	 * faults_memory: Exponential decaying average of faults on a per-node
1099 	 * basis. Scheduling placement decisions are made based on these
1100 	 * counts. The values remain static for the duration of a PTE scan.
1101 	 * faults_cpu: Track the nodes the process was running on when a NUMA
1102 	 * hinting fault was incurred.
1103 	 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1104 	 * during the current scan window. When the scan completes, the counts
1105 	 * in faults_memory and faults_cpu decay and these values are copied.
1106 	 */
1107 	unsigned long			*numa_faults;
1108 	unsigned long			total_numa_faults;
1109 
1110 	/*
1111 	 * numa_faults_locality tracks if faults recorded during the last
1112 	 * scan window were remote/local or failed to migrate. The task scan
1113 	 * period is adapted based on the locality of the faults with different
1114 	 * weights depending on whether they were shared or private faults
1115 	 */
1116 	unsigned long			numa_faults_locality[3];
1117 
1118 	unsigned long			numa_pages_migrated;
1119 #endif /* CONFIG_NUMA_BALANCING */
1120 
1121 #ifdef CONFIG_RSEQ
1122 	struct rseq __user *rseq;
1123 	u32 rseq_sig;
1124 	/*
1125 	 * RmW on rseq_event_mask must be performed atomically
1126 	 * with respect to preemption.
1127 	 */
1128 	unsigned long rseq_event_mask;
1129 #endif
1130 
1131 	struct tlbflush_unmap_batch	tlb_ubc;
1132 
1133 	union {
1134 		refcount_t		rcu_users;
1135 		struct rcu_head		rcu;
1136 	};
1137 
1138 	/* Cache last used pipe for splice(): */
1139 	struct pipe_inode_info		*splice_pipe;
1140 
1141 	struct page_frag		task_frag;
1142 
1143 #ifdef CONFIG_TASK_DELAY_ACCT
1144 	struct task_delay_info		*delays;
1145 #endif
1146 
1147 #ifdef CONFIG_FAULT_INJECTION
1148 	int				make_it_fail;
1149 	unsigned int			fail_nth;
1150 #endif
1151 	/*
1152 	 * When (nr_dirtied >= nr_dirtied_pause), it's time to call
1153 	 * balance_dirty_pages() for a dirty throttling pause:
1154 	 */
1155 	int				nr_dirtied;
1156 	int				nr_dirtied_pause;
1157 	/* Start of a write-and-pause period: */
1158 	unsigned long			dirty_paused_when;
1159 
1160 #ifdef CONFIG_LATENCYTOP
1161 	int				latency_record_count;
1162 	struct latency_record		latency_record[LT_SAVECOUNT];
1163 #endif
1164 	/*
1165 	 * Time slack values; these are used to round up poll() and
1166 	 * select() etc timeout values. These are in nanoseconds.
1167 	 */
1168 	u64				timer_slack_ns;
1169 	u64				default_timer_slack_ns;
1170 
1171 #ifdef CONFIG_KASAN
1172 	unsigned int			kasan_depth;
1173 #endif
1174 
1175 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1176 	/* Index of current stored address in ret_stack: */
1177 	int				curr_ret_stack;
1178 	int				curr_ret_depth;
1179 
1180 	/* Stack of return addresses for return function tracing: */
1181 	struct ftrace_ret_stack		*ret_stack;
1182 
1183 	/* Timestamp for last schedule: */
1184 	unsigned long long		ftrace_timestamp;
1185 
1186 	/*
1187 	 * Number of functions that haven't been traced
1188 	 * because of depth overrun:
1189 	 */
1190 	atomic_t			trace_overrun;
1191 
1192 	/* Pause tracing: */
1193 	atomic_t			tracing_graph_pause;
1194 #endif
1195 
1196 #ifdef CONFIG_TRACING
1197 	/* State flags for use by tracers: */
1198 	unsigned long			trace;
1199 
1200 	/* Bitmask and counter of trace recursion: */
1201 	unsigned long			trace_recursion;
1202 #endif /* CONFIG_TRACING */
1203 
1204 #ifdef CONFIG_KCOV
1205 	/* Coverage collection mode enabled for this task (0 if disabled): */
1206 	unsigned int			kcov_mode;
1207 
1208 	/* Size of the kcov_area: */
1209 	unsigned int			kcov_size;
1210 
1211 	/* Buffer for coverage collection: */
1212 	void				*kcov_area;
1213 
1214 	/* KCOV descriptor wired with this task or NULL: */
1215 	struct kcov			*kcov;
1216 #endif
1217 
1218 #ifdef CONFIG_MEMCG
1219 	struct mem_cgroup		*memcg_in_oom;
1220 	gfp_t				memcg_oom_gfp_mask;
1221 	int				memcg_oom_order;
1222 
1223 	/* Number of pages to reclaim on returning to userland: */
1224 	unsigned int			memcg_nr_pages_over_high;
1225 
1226 	/* Used by memcontrol for targeted memcg charge: */
1227 	struct mem_cgroup		*active_memcg;
1228 #endif
1229 
1230 #ifdef CONFIG_BLK_CGROUP
1231 	struct request_queue		*throttle_queue;
1232 #endif
1233 
1234 #ifdef CONFIG_UPROBES
1235 	struct uprobe_task		*utask;
1236 #endif
1237 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1238 	unsigned int			sequential_io;
1239 	unsigned int			sequential_io_avg;
1240 #endif
1241 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1242 	unsigned long			task_state_change;
1243 #endif
1244 	int				pagefault_disabled;
1245 #ifdef CONFIG_MMU
1246 	struct task_struct		*oom_reaper_list;
1247 #endif
1248 #ifdef CONFIG_VMAP_STACK
1249 	struct vm_struct		*stack_vm_area;
1250 #endif
1251 #ifdef CONFIG_THREAD_INFO_IN_TASK
1252 	/* A live task holds one reference: */
1253 	refcount_t			stack_refcount;
1254 #endif
1255 #ifdef CONFIG_LIVEPATCH
1256 	int patch_state;
1257 #endif
1258 #ifdef CONFIG_SECURITY
1259 	/* Used by LSM modules for access restriction: */
1260 	void				*security;
1261 #endif
1262 
1263 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK
1264 	unsigned long			lowest_stack;
1265 	unsigned long			prev_lowest_stack;
1266 #endif
1267 
1268 	/*
1269 	 * New fields for task_struct should be added above here, so that
1270 	 * they are included in the randomized portion of task_struct.
1271 	 */
1272 	randomized_struct_fields_end
1273 
1274 	/* CPU-specific state of this task: */
1275 	struct thread_struct		thread;
1276 
1277 	/*
1278 	 * WARNING: on x86, 'thread_struct' contains a variable-sized
1279 	 * structure.  It *MUST* be at the end of 'task_struct'.
1280 	 *
1281 	 * Do not put anything below here!
1282 	 */
1283 };
1284 
1285 static inline struct pid *task_pid(struct task_struct *task)
1286 {
1287 	return task->thread_pid;
1288 }
1289 
1290 /*
1291  * the helpers to get the task's different pids as they are seen
1292  * from various namespaces
1293  *
1294  * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1295  * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1296  *                     current.
1297  * task_xid_nr_ns()  : id seen from the ns specified;
1298  *
1299  * see also pid_nr() etc in include/linux/pid.h
1300  */
1301 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, struct pid_namespace *ns);
1302 
1303 static inline pid_t task_pid_nr(struct task_struct *tsk)
1304 {
1305 	return tsk->pid;
1306 }
1307 
1308 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1309 {
1310 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1311 }
1312 
1313 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1314 {
1315 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1316 }
1317 
1318 
1319 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1320 {
1321 	return tsk->tgid;
1322 }
1323 
1324 /**
1325  * pid_alive - check that a task structure is not stale
1326  * @p: Task structure to be checked.
1327  *
1328  * Test if a process is not yet dead (at most zombie state)
1329  * If pid_alive fails, then pointers within the task structure
1330  * can be stale and must not be dereferenced.
1331  *
1332  * Return: 1 if the process is alive. 0 otherwise.
1333  */
1334 static inline int pid_alive(const struct task_struct *p)
1335 {
1336 	return p->thread_pid != NULL;
1337 }
1338 
1339 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1340 {
1341 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1342 }
1343 
1344 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1345 {
1346 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1347 }
1348 
1349 
1350 static inline pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1351 {
1352 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1353 }
1354 
1355 static inline pid_t task_session_vnr(struct task_struct *tsk)
1356 {
1357 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1358 }
1359 
1360 static inline pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1361 {
1362 	return __task_pid_nr_ns(tsk, PIDTYPE_TGID, ns);
1363 }
1364 
1365 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1366 {
1367 	return __task_pid_nr_ns(tsk, PIDTYPE_TGID, NULL);
1368 }
1369 
1370 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1371 {
1372 	pid_t pid = 0;
1373 
1374 	rcu_read_lock();
1375 	if (pid_alive(tsk))
1376 		pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1377 	rcu_read_unlock();
1378 
1379 	return pid;
1380 }
1381 
1382 static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1383 {
1384 	return task_ppid_nr_ns(tsk, &init_pid_ns);
1385 }
1386 
1387 /* Obsolete, do not use: */
1388 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1389 {
1390 	return task_pgrp_nr_ns(tsk, &init_pid_ns);
1391 }
1392 
1393 #define TASK_REPORT_IDLE	(TASK_REPORT + 1)
1394 #define TASK_REPORT_MAX		(TASK_REPORT_IDLE << 1)
1395 
1396 static inline unsigned int task_state_index(struct task_struct *tsk)
1397 {
1398 	unsigned int tsk_state = READ_ONCE(tsk->state);
1399 	unsigned int state = (tsk_state | tsk->exit_state) & TASK_REPORT;
1400 
1401 	BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);
1402 
1403 	if (tsk_state == TASK_IDLE)
1404 		state = TASK_REPORT_IDLE;
1405 
1406 	return fls(state);
1407 }
1408 
1409 static inline char task_index_to_char(unsigned int state)
1410 {
1411 	static const char state_char[] = "RSDTtXZPI";
1412 
1413 	BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1);
1414 
1415 	return state_char[state];
1416 }
1417 
1418 static inline char task_state_to_char(struct task_struct *tsk)
1419 {
1420 	return task_index_to_char(task_state_index(tsk));
1421 }
1422 
1423 /**
1424  * is_global_init - check if a task structure is init. Since init
1425  * is free to have sub-threads we need to check tgid.
1426  * @tsk: Task structure to be checked.
1427  *
1428  * Check if a task structure is the first user space task the kernel created.
1429  *
1430  * Return: 1 if the task structure is init. 0 otherwise.
1431  */
1432 static inline int is_global_init(struct task_struct *tsk)
1433 {
1434 	return task_tgid_nr(tsk) == 1;
1435 }
1436 
1437 extern struct pid *cad_pid;
1438 
1439 /*
1440  * Per process flags
1441  */
1442 #define PF_IDLE			0x00000002	/* I am an IDLE thread */
1443 #define PF_EXITING		0x00000004	/* Getting shut down */
1444 #define PF_EXITPIDONE		0x00000008	/* PI exit done on shut down */
1445 #define PF_VCPU			0x00000010	/* I'm a virtual CPU */
1446 #define PF_WQ_WORKER		0x00000020	/* I'm a workqueue worker */
1447 #define PF_FORKNOEXEC		0x00000040	/* Forked but didn't exec */
1448 #define PF_MCE_PROCESS		0x00000080      /* Process policy on mce errors */
1449 #define PF_SUPERPRIV		0x00000100	/* Used super-user privileges */
1450 #define PF_DUMPCORE		0x00000200	/* Dumped core */
1451 #define PF_SIGNALED		0x00000400	/* Killed by a signal */
1452 #define PF_MEMALLOC		0x00000800	/* Allocating memory */
1453 #define PF_NPROC_EXCEEDED	0x00001000	/* set_user() noticed that RLIMIT_NPROC was exceeded */
1454 #define PF_USED_MATH		0x00002000	/* If unset the fpu must be initialized before use */
1455 #define PF_USED_ASYNC		0x00004000	/* Used async_schedule*(), used by module init */
1456 #define PF_NOFREEZE		0x00008000	/* This thread should not be frozen */
1457 #define PF_FROZEN		0x00010000	/* Frozen for system suspend */
1458 #define PF_KSWAPD		0x00020000	/* I am kswapd */
1459 #define PF_MEMALLOC_NOFS	0x00040000	/* All allocation requests will inherit GFP_NOFS */
1460 #define PF_MEMALLOC_NOIO	0x00080000	/* All allocation requests will inherit GFP_NOIO */
1461 #define PF_LESS_THROTTLE	0x00100000	/* Throttle me less: I clean memory */
1462 #define PF_KTHREAD		0x00200000	/* I am a kernel thread */
1463 #define PF_RANDOMIZE		0x00400000	/* Randomize virtual address space */
1464 #define PF_SWAPWRITE		0x00800000	/* Allowed to write to swap */
1465 #define PF_MEMSTALL		0x01000000	/* Stalled due to lack of memory */
1466 #define PF_UMH			0x02000000	/* I'm an Usermodehelper process */
1467 #define PF_NO_SETAFFINITY	0x04000000	/* Userland is not allowed to meddle with cpus_mask */
1468 #define PF_MCE_EARLY		0x08000000      /* Early kill for mce process policy */
1469 #define PF_MEMALLOC_NOCMA	0x10000000	/* All allocation request will have _GFP_MOVABLE cleared */
1470 #define PF_FREEZER_SKIP		0x40000000	/* Freezer should not count it as freezable */
1471 #define PF_SUSPEND_TASK		0x80000000      /* This thread called freeze_processes() and should not be frozen */
1472 
1473 /*
1474  * Only the _current_ task can read/write to tsk->flags, but other
1475  * tasks can access tsk->flags in readonly mode for example
1476  * with tsk_used_math (like during threaded core dumping).
1477  * There is however an exception to this rule during ptrace
1478  * or during fork: the ptracer task is allowed to write to the
1479  * child->flags of its traced child (same goes for fork, the parent
1480  * can write to the child->flags), because we're guaranteed the
1481  * child is not running and in turn not changing child->flags
1482  * at the same time the parent does it.
1483  */
1484 #define clear_stopped_child_used_math(child)	do { (child)->flags &= ~PF_USED_MATH; } while (0)
1485 #define set_stopped_child_used_math(child)	do { (child)->flags |= PF_USED_MATH; } while (0)
1486 #define clear_used_math()			clear_stopped_child_used_math(current)
1487 #define set_used_math()				set_stopped_child_used_math(current)
1488 
1489 #define conditional_stopped_child_used_math(condition, child) \
1490 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1491 
1492 #define conditional_used_math(condition)	conditional_stopped_child_used_math(condition, current)
1493 
1494 #define copy_to_stopped_child_used_math(child) \
1495 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1496 
1497 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1498 #define tsk_used_math(p)			((p)->flags & PF_USED_MATH)
1499 #define used_math()				tsk_used_math(current)
1500 
1501 static inline bool is_percpu_thread(void)
1502 {
1503 #ifdef CONFIG_SMP
1504 	return (current->flags & PF_NO_SETAFFINITY) &&
1505 		(current->nr_cpus_allowed  == 1);
1506 #else
1507 	return true;
1508 #endif
1509 }
1510 
1511 /* Per-process atomic flags. */
1512 #define PFA_NO_NEW_PRIVS		0	/* May not gain new privileges. */
1513 #define PFA_SPREAD_PAGE			1	/* Spread page cache over cpuset */
1514 #define PFA_SPREAD_SLAB			2	/* Spread some slab caches over cpuset */
1515 #define PFA_SPEC_SSB_DISABLE		3	/* Speculative Store Bypass disabled */
1516 #define PFA_SPEC_SSB_FORCE_DISABLE	4	/* Speculative Store Bypass force disabled*/
1517 #define PFA_SPEC_IB_DISABLE		5	/* Indirect branch speculation restricted */
1518 #define PFA_SPEC_IB_FORCE_DISABLE	6	/* Indirect branch speculation permanently restricted */
1519 #define PFA_SPEC_SSB_NOEXEC		7	/* Speculative Store Bypass clear on execve() */
1520 
1521 #define TASK_PFA_TEST(name, func)					\
1522 	static inline bool task_##func(struct task_struct *p)		\
1523 	{ return test_bit(PFA_##name, &p->atomic_flags); }
1524 
1525 #define TASK_PFA_SET(name, func)					\
1526 	static inline void task_set_##func(struct task_struct *p)	\
1527 	{ set_bit(PFA_##name, &p->atomic_flags); }
1528 
1529 #define TASK_PFA_CLEAR(name, func)					\
1530 	static inline void task_clear_##func(struct task_struct *p)	\
1531 	{ clear_bit(PFA_##name, &p->atomic_flags); }
1532 
1533 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1534 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1535 
1536 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1537 TASK_PFA_SET(SPREAD_PAGE, spread_page)
1538 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
1539 
1540 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
1541 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
1542 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1543 
1544 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable)
1545 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable)
1546 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable)
1547 
1548 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1549 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1550 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1551 
1552 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1553 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1554 
1555 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable)
1556 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable)
1557 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable)
1558 
1559 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1560 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1561 
1562 static inline void
1563 current_restore_flags(unsigned long orig_flags, unsigned long flags)
1564 {
1565 	current->flags &= ~flags;
1566 	current->flags |= orig_flags & flags;
1567 }
1568 
1569 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
1570 extern int task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
1571 #ifdef CONFIG_SMP
1572 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask);
1573 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
1574 #else
1575 static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
1576 {
1577 }
1578 static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
1579 {
1580 	if (!cpumask_test_cpu(0, new_mask))
1581 		return -EINVAL;
1582 	return 0;
1583 }
1584 #endif
1585 
1586 extern int yield_to(struct task_struct *p, bool preempt);
1587 extern void set_user_nice(struct task_struct *p, long nice);
1588 extern int task_prio(const struct task_struct *p);
1589 
1590 /**
1591  * task_nice - return the nice value of a given task.
1592  * @p: the task in question.
1593  *
1594  * Return: The nice value [ -20 ... 0 ... 19 ].
1595  */
1596 static inline int task_nice(const struct task_struct *p)
1597 {
1598 	return PRIO_TO_NICE((p)->static_prio);
1599 }
1600 
1601 extern int can_nice(const struct task_struct *p, const int nice);
1602 extern int task_curr(const struct task_struct *p);
1603 extern int idle_cpu(int cpu);
1604 extern int available_idle_cpu(int cpu);
1605 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
1606 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
1607 extern int sched_setattr(struct task_struct *, const struct sched_attr *);
1608 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *);
1609 extern struct task_struct *idle_task(int cpu);
1610 
1611 /**
1612  * is_idle_task - is the specified task an idle task?
1613  * @p: the task in question.
1614  *
1615  * Return: 1 if @p is an idle task. 0 otherwise.
1616  */
1617 static inline bool is_idle_task(const struct task_struct *p)
1618 {
1619 	return !!(p->flags & PF_IDLE);
1620 }
1621 
1622 extern struct task_struct *curr_task(int cpu);
1623 extern void ia64_set_curr_task(int cpu, struct task_struct *p);
1624 
1625 void yield(void);
1626 
1627 union thread_union {
1628 #ifndef CONFIG_ARCH_TASK_STRUCT_ON_STACK
1629 	struct task_struct task;
1630 #endif
1631 #ifndef CONFIG_THREAD_INFO_IN_TASK
1632 	struct thread_info thread_info;
1633 #endif
1634 	unsigned long stack[THREAD_SIZE/sizeof(long)];
1635 };
1636 
1637 #ifndef CONFIG_THREAD_INFO_IN_TASK
1638 extern struct thread_info init_thread_info;
1639 #endif
1640 
1641 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];
1642 
1643 #ifdef CONFIG_THREAD_INFO_IN_TASK
1644 static inline struct thread_info *task_thread_info(struct task_struct *task)
1645 {
1646 	return &task->thread_info;
1647 }
1648 #elif !defined(__HAVE_THREAD_FUNCTIONS)
1649 # define task_thread_info(task)	((struct thread_info *)(task)->stack)
1650 #endif
1651 
1652 /*
1653  * find a task by one of its numerical ids
1654  *
1655  * find_task_by_pid_ns():
1656  *      finds a task by its pid in the specified namespace
1657  * find_task_by_vpid():
1658  *      finds a task by its virtual pid
1659  *
1660  * see also find_vpid() etc in include/linux/pid.h
1661  */
1662 
1663 extern struct task_struct *find_task_by_vpid(pid_t nr);
1664 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns);
1665 
1666 /*
1667  * find a task by its virtual pid and get the task struct
1668  */
1669 extern struct task_struct *find_get_task_by_vpid(pid_t nr);
1670 
1671 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1672 extern int wake_up_process(struct task_struct *tsk);
1673 extern void wake_up_new_task(struct task_struct *tsk);
1674 
1675 #ifdef CONFIG_SMP
1676 extern void kick_process(struct task_struct *tsk);
1677 #else
1678 static inline void kick_process(struct task_struct *tsk) { }
1679 #endif
1680 
1681 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
1682 
1683 static inline void set_task_comm(struct task_struct *tsk, const char *from)
1684 {
1685 	__set_task_comm(tsk, from, false);
1686 }
1687 
1688 extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk);
1689 #define get_task_comm(buf, tsk) ({			\
1690 	BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN);	\
1691 	__get_task_comm(buf, sizeof(buf), tsk);		\
1692 })
1693 
1694 #ifdef CONFIG_SMP
1695 void scheduler_ipi(void);
1696 extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
1697 #else
1698 static inline void scheduler_ipi(void) { }
1699 static inline unsigned long wait_task_inactive(struct task_struct *p, long match_state)
1700 {
1701 	return 1;
1702 }
1703 #endif
1704 
1705 /*
1706  * Set thread flags in other task's structures.
1707  * See asm/thread_info.h for TIF_xxxx flags available:
1708  */
1709 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1710 {
1711 	set_ti_thread_flag(task_thread_info(tsk), flag);
1712 }
1713 
1714 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1715 {
1716 	clear_ti_thread_flag(task_thread_info(tsk), flag);
1717 }
1718 
1719 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag,
1720 					  bool value)
1721 {
1722 	update_ti_thread_flag(task_thread_info(tsk), flag, value);
1723 }
1724 
1725 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1726 {
1727 	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1728 }
1729 
1730 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1731 {
1732 	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1733 }
1734 
1735 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1736 {
1737 	return test_ti_thread_flag(task_thread_info(tsk), flag);
1738 }
1739 
1740 static inline void set_tsk_need_resched(struct task_struct *tsk)
1741 {
1742 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1743 }
1744 
1745 static inline void clear_tsk_need_resched(struct task_struct *tsk)
1746 {
1747 	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1748 }
1749 
1750 static inline int test_tsk_need_resched(struct task_struct *tsk)
1751 {
1752 	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
1753 }
1754 
1755 /*
1756  * cond_resched() and cond_resched_lock(): latency reduction via
1757  * explicit rescheduling in places that are safe. The return
1758  * value indicates whether a reschedule was done in fact.
1759  * cond_resched_lock() will drop the spinlock before scheduling,
1760  */
1761 #ifndef CONFIG_PREEMPTION
1762 extern int _cond_resched(void);
1763 #else
1764 static inline int _cond_resched(void) { return 0; }
1765 #endif
1766 
1767 #define cond_resched() ({			\
1768 	___might_sleep(__FILE__, __LINE__, 0);	\
1769 	_cond_resched();			\
1770 })
1771 
1772 extern int __cond_resched_lock(spinlock_t *lock);
1773 
1774 #define cond_resched_lock(lock) ({				\
1775 	___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
1776 	__cond_resched_lock(lock);				\
1777 })
1778 
1779 static inline void cond_resched_rcu(void)
1780 {
1781 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
1782 	rcu_read_unlock();
1783 	cond_resched();
1784 	rcu_read_lock();
1785 #endif
1786 }
1787 
1788 /*
1789  * Does a critical section need to be broken due to another
1790  * task waiting?: (technically does not depend on CONFIG_PREEMPTION,
1791  * but a general need for low latency)
1792  */
1793 static inline int spin_needbreak(spinlock_t *lock)
1794 {
1795 #ifdef CONFIG_PREEMPTION
1796 	return spin_is_contended(lock);
1797 #else
1798 	return 0;
1799 #endif
1800 }
1801 
1802 static __always_inline bool need_resched(void)
1803 {
1804 	return unlikely(tif_need_resched());
1805 }
1806 
1807 /*
1808  * Wrappers for p->thread_info->cpu access. No-op on UP.
1809  */
1810 #ifdef CONFIG_SMP
1811 
1812 static inline unsigned int task_cpu(const struct task_struct *p)
1813 {
1814 #ifdef CONFIG_THREAD_INFO_IN_TASK
1815 	return READ_ONCE(p->cpu);
1816 #else
1817 	return READ_ONCE(task_thread_info(p)->cpu);
1818 #endif
1819 }
1820 
1821 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
1822 
1823 #else
1824 
1825 static inline unsigned int task_cpu(const struct task_struct *p)
1826 {
1827 	return 0;
1828 }
1829 
1830 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1831 {
1832 }
1833 
1834 #endif /* CONFIG_SMP */
1835 
1836 /*
1837  * In order to reduce various lock holder preemption latencies provide an
1838  * interface to see if a vCPU is currently running or not.
1839  *
1840  * This allows us to terminate optimistic spin loops and block, analogous to
1841  * the native optimistic spin heuristic of testing if the lock owner task is
1842  * running or not.
1843  */
1844 #ifndef vcpu_is_preempted
1845 static inline bool vcpu_is_preempted(int cpu)
1846 {
1847 	return false;
1848 }
1849 #endif
1850 
1851 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
1852 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
1853 
1854 #ifndef TASK_SIZE_OF
1855 #define TASK_SIZE_OF(tsk)	TASK_SIZE
1856 #endif
1857 
1858 #ifdef CONFIG_RSEQ
1859 
1860 /*
1861  * Map the event mask on the user-space ABI enum rseq_cs_flags
1862  * for direct mask checks.
1863  */
1864 enum rseq_event_mask_bits {
1865 	RSEQ_EVENT_PREEMPT_BIT	= RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT,
1866 	RSEQ_EVENT_SIGNAL_BIT	= RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT,
1867 	RSEQ_EVENT_MIGRATE_BIT	= RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT,
1868 };
1869 
1870 enum rseq_event_mask {
1871 	RSEQ_EVENT_PREEMPT	= (1U << RSEQ_EVENT_PREEMPT_BIT),
1872 	RSEQ_EVENT_SIGNAL	= (1U << RSEQ_EVENT_SIGNAL_BIT),
1873 	RSEQ_EVENT_MIGRATE	= (1U << RSEQ_EVENT_MIGRATE_BIT),
1874 };
1875 
1876 static inline void rseq_set_notify_resume(struct task_struct *t)
1877 {
1878 	if (t->rseq)
1879 		set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
1880 }
1881 
1882 void __rseq_handle_notify_resume(struct ksignal *sig, struct pt_regs *regs);
1883 
1884 static inline void rseq_handle_notify_resume(struct ksignal *ksig,
1885 					     struct pt_regs *regs)
1886 {
1887 	if (current->rseq)
1888 		__rseq_handle_notify_resume(ksig, regs);
1889 }
1890 
1891 static inline void rseq_signal_deliver(struct ksignal *ksig,
1892 				       struct pt_regs *regs)
1893 {
1894 	preempt_disable();
1895 	__set_bit(RSEQ_EVENT_SIGNAL_BIT, &current->rseq_event_mask);
1896 	preempt_enable();
1897 	rseq_handle_notify_resume(ksig, regs);
1898 }
1899 
1900 /* rseq_preempt() requires preemption to be disabled. */
1901 static inline void rseq_preempt(struct task_struct *t)
1902 {
1903 	__set_bit(RSEQ_EVENT_PREEMPT_BIT, &t->rseq_event_mask);
1904 	rseq_set_notify_resume(t);
1905 }
1906 
1907 /* rseq_migrate() requires preemption to be disabled. */
1908 static inline void rseq_migrate(struct task_struct *t)
1909 {
1910 	__set_bit(RSEQ_EVENT_MIGRATE_BIT, &t->rseq_event_mask);
1911 	rseq_set_notify_resume(t);
1912 }
1913 
1914 /*
1915  * If parent process has a registered restartable sequences area, the
1916  * child inherits. Only applies when forking a process, not a thread.
1917  */
1918 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
1919 {
1920 	if (clone_flags & CLONE_THREAD) {
1921 		t->rseq = NULL;
1922 		t->rseq_sig = 0;
1923 		t->rseq_event_mask = 0;
1924 	} else {
1925 		t->rseq = current->rseq;
1926 		t->rseq_sig = current->rseq_sig;
1927 		t->rseq_event_mask = current->rseq_event_mask;
1928 	}
1929 }
1930 
1931 static inline void rseq_execve(struct task_struct *t)
1932 {
1933 	t->rseq = NULL;
1934 	t->rseq_sig = 0;
1935 	t->rseq_event_mask = 0;
1936 }
1937 
1938 #else
1939 
1940 static inline void rseq_set_notify_resume(struct task_struct *t)
1941 {
1942 }
1943 static inline void rseq_handle_notify_resume(struct ksignal *ksig,
1944 					     struct pt_regs *regs)
1945 {
1946 }
1947 static inline void rseq_signal_deliver(struct ksignal *ksig,
1948 				       struct pt_regs *regs)
1949 {
1950 }
1951 static inline void rseq_preempt(struct task_struct *t)
1952 {
1953 }
1954 static inline void rseq_migrate(struct task_struct *t)
1955 {
1956 }
1957 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
1958 {
1959 }
1960 static inline void rseq_execve(struct task_struct *t)
1961 {
1962 }
1963 
1964 #endif
1965 
1966 void __exit_umh(struct task_struct *tsk);
1967 
1968 static inline void exit_umh(struct task_struct *tsk)
1969 {
1970 	if (unlikely(tsk->flags & PF_UMH))
1971 		__exit_umh(tsk);
1972 }
1973 
1974 #ifdef CONFIG_DEBUG_RSEQ
1975 
1976 void rseq_syscall(struct pt_regs *regs);
1977 
1978 #else
1979 
1980 static inline void rseq_syscall(struct pt_regs *regs)
1981 {
1982 }
1983 
1984 #endif
1985 
1986 const struct sched_avg *sched_trace_cfs_rq_avg(struct cfs_rq *cfs_rq);
1987 char *sched_trace_cfs_rq_path(struct cfs_rq *cfs_rq, char *str, int len);
1988 int sched_trace_cfs_rq_cpu(struct cfs_rq *cfs_rq);
1989 
1990 const struct sched_avg *sched_trace_rq_avg_rt(struct rq *rq);
1991 const struct sched_avg *sched_trace_rq_avg_dl(struct rq *rq);
1992 const struct sched_avg *sched_trace_rq_avg_irq(struct rq *rq);
1993 
1994 int sched_trace_rq_cpu(struct rq *rq);
1995 
1996 const struct cpumask *sched_trace_rd_span(struct root_domain *rd);
1997 
1998 #endif
1999