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.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/task_io_accounting.h>
40#include <linux/posix-timers_types.h>
41#include <linux/restart_block.h>
42#include <uapi/linux/rseq.h>
43#include <linux/seqlock_types.h>
44#include <linux/kcsan.h>
45#include <linux/rv.h>
46#include <linux/livepatch_sched.h>
47#include <linux/uidgid_types.h>
48#include <asm/kmap_size.h>
49
50/* task_struct member predeclarations (sorted alphabetically): */
51struct audit_context;
52struct bio_list;
53struct blk_plug;
54struct bpf_local_storage;
55struct bpf_run_ctx;
56struct capture_control;
57struct cfs_rq;
58struct fs_struct;
59struct futex_pi_state;
60struct io_context;
61struct io_uring_task;
62struct mempolicy;
63struct nameidata;
64struct nsproxy;
65struct perf_event_context;
66struct pid_namespace;
67struct pipe_inode_info;
68struct rcu_node;
69struct reclaim_state;
70struct robust_list_head;
71struct root_domain;
72struct rq;
73struct sched_attr;
74struct sched_dl_entity;
75struct seq_file;
76struct sighand_struct;
77struct signal_struct;
78struct task_delay_info;
79struct task_group;
80struct task_struct;
81struct user_event_mm;
82
83/*
84 * Task state bitmask. NOTE! These bits are also
85 * encoded in fs/proc/array.c: get_task_state().
86 *
87 * We have two separate sets of flags: task->__state
88 * is about runnability, while task->exit_state are
89 * about the task exiting. Confusing, but this way
90 * modifying one set can't modify the other one by
91 * mistake.
92 */
93
94/* Used in tsk->__state: */
95#define TASK_RUNNING			0x00000000
96#define TASK_INTERRUPTIBLE		0x00000001
97#define TASK_UNINTERRUPTIBLE		0x00000002
98#define __TASK_STOPPED			0x00000004
99#define __TASK_TRACED			0x00000008
100/* Used in tsk->exit_state: */
101#define EXIT_DEAD			0x00000010
102#define EXIT_ZOMBIE			0x00000020
103#define EXIT_TRACE			(EXIT_ZOMBIE | EXIT_DEAD)
104/* Used in tsk->__state again: */
105#define TASK_PARKED			0x00000040
106#define TASK_DEAD			0x00000080
107#define TASK_WAKEKILL			0x00000100
108#define TASK_WAKING			0x00000200
109#define TASK_NOLOAD			0x00000400
110#define TASK_NEW			0x00000800
111#define TASK_RTLOCK_WAIT		0x00001000
112#define TASK_FREEZABLE			0x00002000
113#define __TASK_FREEZABLE_UNSAFE	       (0x00004000 * IS_ENABLED(CONFIG_LOCKDEP))
114#define TASK_FROZEN			0x00008000
115#define TASK_STATE_MAX			0x00010000
116
117#define TASK_ANY			(TASK_STATE_MAX-1)
118
119/*
120 * DO NOT ADD ANY NEW USERS !
121 */
122#define TASK_FREEZABLE_UNSAFE		(TASK_FREEZABLE | __TASK_FREEZABLE_UNSAFE)
123
124/* Convenience macros for the sake of set_current_state: */
125#define TASK_KILLABLE			(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
126#define TASK_STOPPED			(TASK_WAKEKILL | __TASK_STOPPED)
127#define TASK_TRACED			__TASK_TRACED
128
129#define TASK_IDLE			(TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
130
131/* Convenience macros for the sake of wake_up(): */
132#define TASK_NORMAL			(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
133
134/* get_task_state(): */
135#define TASK_REPORT			(TASK_RUNNING | TASK_INTERRUPTIBLE | \
136					 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
137					 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \
138					 TASK_PARKED)
139
140#define task_is_running(task)		(READ_ONCE((task)->__state) == TASK_RUNNING)
141
142#define task_is_traced(task)		((READ_ONCE(task->jobctl) & JOBCTL_TRACED) != 0)
143#define task_is_stopped(task)		((READ_ONCE(task->jobctl) & JOBCTL_STOPPED) != 0)
144#define task_is_stopped_or_traced(task)	((READ_ONCE(task->jobctl) & (JOBCTL_STOPPED | JOBCTL_TRACED)) != 0)
145
146/*
147 * Special states are those that do not use the normal wait-loop pattern. See
148 * the comment with set_special_state().
149 */
150#define is_special_task_state(state)				\
151	((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | TASK_DEAD))
152
153#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
154# define debug_normal_state_change(state_value)				\
155	do {								\
156		WARN_ON_ONCE(is_special_task_state(state_value));	\
157		current->task_state_change = _THIS_IP_;			\
158	} while (0)
159
160# define debug_special_state_change(state_value)			\
161	do {								\
162		WARN_ON_ONCE(!is_special_task_state(state_value));	\
163		current->task_state_change = _THIS_IP_;			\
164	} while (0)
165
166# define debug_rtlock_wait_set_state()					\
167	do {								 \
168		current->saved_state_change = current->task_state_change;\
169		current->task_state_change = _THIS_IP_;			 \
170	} while (0)
171
172# define debug_rtlock_wait_restore_state()				\
173	do {								 \
174		current->task_state_change = current->saved_state_change;\
175	} while (0)
176
177#else
178# define debug_normal_state_change(cond)	do { } while (0)
179# define debug_special_state_change(cond)	do { } while (0)
180# define debug_rtlock_wait_set_state()		do { } while (0)
181# define debug_rtlock_wait_restore_state()	do { } while (0)
182#endif
183
184/*
185 * set_current_state() includes a barrier so that the write of current->__state
186 * is correctly serialised wrt the caller's subsequent test of whether to
187 * actually sleep:
188 *
189 *   for (;;) {
190 *	set_current_state(TASK_UNINTERRUPTIBLE);
191 *	if (CONDITION)
192 *	   break;
193 *
194 *	schedule();
195 *   }
196 *   __set_current_state(TASK_RUNNING);
197 *
198 * If the caller does not need such serialisation (because, for instance, the
199 * CONDITION test and condition change and wakeup are under the same lock) then
200 * use __set_current_state().
201 *
202 * The above is typically ordered against the wakeup, which does:
203 *
204 *   CONDITION = 1;
205 *   wake_up_state(p, TASK_UNINTERRUPTIBLE);
206 *
207 * where wake_up_state()/try_to_wake_up() executes a full memory barrier before
208 * accessing p->__state.
209 *
210 * Wakeup will do: if (@state & p->__state) p->__state = TASK_RUNNING, that is,
211 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a
212 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING).
213 *
214 * However, with slightly different timing the wakeup TASK_RUNNING store can
215 * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not
216 * a problem either because that will result in one extra go around the loop
217 * and our @cond test will save the day.
218 *
219 * Also see the comments of try_to_wake_up().
220 */
221#define __set_current_state(state_value)				\
222	do {								\
223		debug_normal_state_change((state_value));		\
224		WRITE_ONCE(current->__state, (state_value));		\
225	} while (0)
226
227#define set_current_state(state_value)					\
228	do {								\
229		debug_normal_state_change((state_value));		\
230		smp_store_mb(current->__state, (state_value));		\
231	} while (0)
232
233/*
234 * set_special_state() should be used for those states when the blocking task
235 * can not use the regular condition based wait-loop. In that case we must
236 * serialize against wakeups such that any possible in-flight TASK_RUNNING
237 * stores will not collide with our state change.
238 */
239#define set_special_state(state_value)					\
240	do {								\
241		unsigned long flags; /* may shadow */			\
242									\
243		raw_spin_lock_irqsave(&current->pi_lock, flags);	\
244		debug_special_state_change((state_value));		\
245		WRITE_ONCE(current->__state, (state_value));		\
246		raw_spin_unlock_irqrestore(&current->pi_lock, flags);	\
247	} while (0)
248
249/*
250 * PREEMPT_RT specific variants for "sleeping" spin/rwlocks
251 *
252 * RT's spin/rwlock substitutions are state preserving. The state of the
253 * task when blocking on the lock is saved in task_struct::saved_state and
254 * restored after the lock has been acquired.  These operations are
255 * serialized by task_struct::pi_lock against try_to_wake_up(). Any non RT
256 * lock related wakeups while the task is blocked on the lock are
257 * redirected to operate on task_struct::saved_state to ensure that these
258 * are not dropped. On restore task_struct::saved_state is set to
259 * TASK_RUNNING so any wakeup attempt redirected to saved_state will fail.
260 *
261 * The lock operation looks like this:
262 *
263 *	current_save_and_set_rtlock_wait_state();
264 *	for (;;) {
265 *		if (try_lock())
266 *			break;
267 *		raw_spin_unlock_irq(&lock->wait_lock);
268 *		schedule_rtlock();
269 *		raw_spin_lock_irq(&lock->wait_lock);
270 *		set_current_state(TASK_RTLOCK_WAIT);
271 *	}
272 *	current_restore_rtlock_saved_state();
273 */
274#define current_save_and_set_rtlock_wait_state()			\
275	do {								\
276		lockdep_assert_irqs_disabled();				\
277		raw_spin_lock(&current->pi_lock);			\
278		current->saved_state = current->__state;		\
279		debug_rtlock_wait_set_state();				\
280		WRITE_ONCE(current->__state, TASK_RTLOCK_WAIT);		\
281		raw_spin_unlock(&current->pi_lock);			\
282	} while (0);
283
284#define current_restore_rtlock_saved_state()				\
285	do {								\
286		lockdep_assert_irqs_disabled();				\
287		raw_spin_lock(&current->pi_lock);			\
288		debug_rtlock_wait_restore_state();			\
289		WRITE_ONCE(current->__state, current->saved_state);	\
290		current->saved_state = TASK_RUNNING;			\
291		raw_spin_unlock(&current->pi_lock);			\
292	} while (0);
293
294#define get_current_state()	READ_ONCE(current->__state)
295
296/*
297 * Define the task command name length as enum, then it can be visible to
298 * BPF programs.
299 */
300enum {
301	TASK_COMM_LEN = 16,
302};
303
304extern void scheduler_tick(void);
305
306#define	MAX_SCHEDULE_TIMEOUT		LONG_MAX
307
308extern long schedule_timeout(long timeout);
309extern long schedule_timeout_interruptible(long timeout);
310extern long schedule_timeout_killable(long timeout);
311extern long schedule_timeout_uninterruptible(long timeout);
312extern long schedule_timeout_idle(long timeout);
313asmlinkage void schedule(void);
314extern void schedule_preempt_disabled(void);
315asmlinkage void preempt_schedule_irq(void);
316#ifdef CONFIG_PREEMPT_RT
317 extern void schedule_rtlock(void);
318#endif
319
320extern int __must_check io_schedule_prepare(void);
321extern void io_schedule_finish(int token);
322extern long io_schedule_timeout(long timeout);
323extern void io_schedule(void);
324
325/**
326 * struct prev_cputime - snapshot of system and user cputime
327 * @utime: time spent in user mode
328 * @stime: time spent in system mode
329 * @lock: protects the above two fields
330 *
331 * Stores previous user/system time values such that we can guarantee
332 * monotonicity.
333 */
334struct prev_cputime {
335#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
336	u64				utime;
337	u64				stime;
338	raw_spinlock_t			lock;
339#endif
340};
341
342enum vtime_state {
343	/* Task is sleeping or running in a CPU with VTIME inactive: */
344	VTIME_INACTIVE = 0,
345	/* Task is idle */
346	VTIME_IDLE,
347	/* Task runs in kernelspace in a CPU with VTIME active: */
348	VTIME_SYS,
349	/* Task runs in userspace in a CPU with VTIME active: */
350	VTIME_USER,
351	/* Task runs as guests in a CPU with VTIME active: */
352	VTIME_GUEST,
353};
354
355struct vtime {
356	seqcount_t		seqcount;
357	unsigned long long	starttime;
358	enum vtime_state	state;
359	unsigned int		cpu;
360	u64			utime;
361	u64			stime;
362	u64			gtime;
363};
364
365/*
366 * Utilization clamp constraints.
367 * @UCLAMP_MIN:	Minimum utilization
368 * @UCLAMP_MAX:	Maximum utilization
369 * @UCLAMP_CNT:	Utilization clamp constraints count
370 */
371enum uclamp_id {
372	UCLAMP_MIN = 0,
373	UCLAMP_MAX,
374	UCLAMP_CNT
375};
376
377#ifdef CONFIG_SMP
378extern struct root_domain def_root_domain;
379extern struct mutex sched_domains_mutex;
380#endif
381
382struct sched_param {
383	int sched_priority;
384};
385
386struct sched_info {
387#ifdef CONFIG_SCHED_INFO
388	/* Cumulative counters: */
389
390	/* # of times we have run on this CPU: */
391	unsigned long			pcount;
392
393	/* Time spent waiting on a runqueue: */
394	unsigned long long		run_delay;
395
396	/* Timestamps: */
397
398	/* When did we last run on a CPU? */
399	unsigned long long		last_arrival;
400
401	/* When were we last queued to run? */
402	unsigned long long		last_queued;
403
404#endif /* CONFIG_SCHED_INFO */
405};
406
407/*
408 * Integer metrics need fixed point arithmetic, e.g., sched/fair
409 * has a few: load, load_avg, util_avg, freq, and capacity.
410 *
411 * We define a basic fixed point arithmetic range, and then formalize
412 * all these metrics based on that basic range.
413 */
414# define SCHED_FIXEDPOINT_SHIFT		10
415# define SCHED_FIXEDPOINT_SCALE		(1L << SCHED_FIXEDPOINT_SHIFT)
416
417/* Increase resolution of cpu_capacity calculations */
418# define SCHED_CAPACITY_SHIFT		SCHED_FIXEDPOINT_SHIFT
419# define SCHED_CAPACITY_SCALE		(1L << SCHED_CAPACITY_SHIFT)
420
421struct load_weight {
422	unsigned long			weight;
423	u32				inv_weight;
424};
425
426/*
427 * The load/runnable/util_avg accumulates an infinite geometric series
428 * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c).
429 *
430 * [load_avg definition]
431 *
432 *   load_avg = runnable% * scale_load_down(load)
433 *
434 * [runnable_avg definition]
435 *
436 *   runnable_avg = runnable% * SCHED_CAPACITY_SCALE
437 *
438 * [util_avg definition]
439 *
440 *   util_avg = running% * SCHED_CAPACITY_SCALE
441 *
442 * where runnable% is the time ratio that a sched_entity is runnable and
443 * running% the time ratio that a sched_entity is running.
444 *
445 * For cfs_rq, they are the aggregated values of all runnable and blocked
446 * sched_entities.
447 *
448 * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU
449 * capacity scaling. The scaling is done through the rq_clock_pelt that is used
450 * for computing those signals (see update_rq_clock_pelt())
451 *
452 * N.B., the above ratios (runnable% and running%) themselves are in the
453 * range of [0, 1]. To do fixed point arithmetics, we therefore scale them
454 * to as large a range as necessary. This is for example reflected by
455 * util_avg's SCHED_CAPACITY_SCALE.
456 *
457 * [Overflow issue]
458 *
459 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
460 * with the highest load (=88761), always runnable on a single cfs_rq,
461 * and should not overflow as the number already hits PID_MAX_LIMIT.
462 *
463 * For all other cases (including 32-bit kernels), struct load_weight's
464 * weight will overflow first before we do, because:
465 *
466 *    Max(load_avg) <= Max(load.weight)
467 *
468 * Then it is the load_weight's responsibility to consider overflow
469 * issues.
470 */
471struct sched_avg {
472	u64				last_update_time;
473	u64				load_sum;
474	u64				runnable_sum;
475	u32				util_sum;
476	u32				period_contrib;
477	unsigned long			load_avg;
478	unsigned long			runnable_avg;
479	unsigned long			util_avg;
480	unsigned int			util_est;
481} ____cacheline_aligned;
482
483/*
484 * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg
485 * updates. When a task is dequeued, its util_est should not be updated if its
486 * util_avg has not been updated in the meantime.
487 * This information is mapped into the MSB bit of util_est at dequeue time.
488 * Since max value of util_est for a task is 1024 (PELT util_avg for a task)
489 * it is safe to use MSB.
490 */
491#define UTIL_EST_WEIGHT_SHIFT		2
492#define UTIL_AVG_UNCHANGED		0x80000000
493
494struct sched_statistics {
495#ifdef CONFIG_SCHEDSTATS
496	u64				wait_start;
497	u64				wait_max;
498	u64				wait_count;
499	u64				wait_sum;
500	u64				iowait_count;
501	u64				iowait_sum;
502
503	u64				sleep_start;
504	u64				sleep_max;
505	s64				sum_sleep_runtime;
506
507	u64				block_start;
508	u64				block_max;
509	s64				sum_block_runtime;
510
511	s64				exec_max;
512	u64				slice_max;
513
514	u64				nr_migrations_cold;
515	u64				nr_failed_migrations_affine;
516	u64				nr_failed_migrations_running;
517	u64				nr_failed_migrations_hot;
518	u64				nr_forced_migrations;
519
520	u64				nr_wakeups;
521	u64				nr_wakeups_sync;
522	u64				nr_wakeups_migrate;
523	u64				nr_wakeups_local;
524	u64				nr_wakeups_remote;
525	u64				nr_wakeups_affine;
526	u64				nr_wakeups_affine_attempts;
527	u64				nr_wakeups_passive;
528	u64				nr_wakeups_idle;
529
530#ifdef CONFIG_SCHED_CORE
531	u64				core_forceidle_sum;
532#endif
533#endif /* CONFIG_SCHEDSTATS */
534} ____cacheline_aligned;
535
536struct sched_entity {
537	/* For load-balancing: */
538	struct load_weight		load;
539	struct rb_node			run_node;
540	u64				deadline;
541	u64				min_vruntime;
542
543	struct list_head		group_node;
544	unsigned int			on_rq;
545
546	u64				exec_start;
547	u64				sum_exec_runtime;
548	u64				prev_sum_exec_runtime;
549	u64				vruntime;
550	s64				vlag;
551	u64				slice;
552
553	u64				nr_migrations;
554
555#ifdef CONFIG_FAIR_GROUP_SCHED
556	int				depth;
557	struct sched_entity		*parent;
558	/* rq on which this entity is (to be) queued: */
559	struct cfs_rq			*cfs_rq;
560	/* rq "owned" by this entity/group: */
561	struct cfs_rq			*my_q;
562	/* cached value of my_q->h_nr_running */
563	unsigned long			runnable_weight;
564#endif
565
566#ifdef CONFIG_SMP
567	/*
568	 * Per entity load average tracking.
569	 *
570	 * Put into separate cache line so it does not
571	 * collide with read-mostly values above.
572	 */
573	struct sched_avg		avg;
574#endif
575};
576
577struct sched_rt_entity {
578	struct list_head		run_list;
579	unsigned long			timeout;
580	unsigned long			watchdog_stamp;
581	unsigned int			time_slice;
582	unsigned short			on_rq;
583	unsigned short			on_list;
584
585	struct sched_rt_entity		*back;
586#ifdef CONFIG_RT_GROUP_SCHED
587	struct sched_rt_entity		*parent;
588	/* rq on which this entity is (to be) queued: */
589	struct rt_rq			*rt_rq;
590	/* rq "owned" by this entity/group: */
591	struct rt_rq			*my_q;
592#endif
593} __randomize_layout;
594
595typedef bool (*dl_server_has_tasks_f)(struct sched_dl_entity *);
596typedef struct task_struct *(*dl_server_pick_f)(struct sched_dl_entity *);
597
598struct sched_dl_entity {
599	struct rb_node			rb_node;
600
601	/*
602	 * Original scheduling parameters. Copied here from sched_attr
603	 * during sched_setattr(), they will remain the same until
604	 * the next sched_setattr().
605	 */
606	u64				dl_runtime;	/* Maximum runtime for each instance	*/
607	u64				dl_deadline;	/* Relative deadline of each instance	*/
608	u64				dl_period;	/* Separation of two instances (period) */
609	u64				dl_bw;		/* dl_runtime / dl_period		*/
610	u64				dl_density;	/* dl_runtime / dl_deadline		*/
611
612	/*
613	 * Actual scheduling parameters. Initialized with the values above,
614	 * they are continuously updated during task execution. Note that
615	 * the remaining runtime could be < 0 in case we are in overrun.
616	 */
617	s64				runtime;	/* Remaining runtime for this instance	*/
618	u64				deadline;	/* Absolute deadline for this instance	*/
619	unsigned int			flags;		/* Specifying the scheduler behaviour	*/
620
621	/*
622	 * Some bool flags:
623	 *
624	 * @dl_throttled tells if we exhausted the runtime. If so, the
625	 * task has to wait for a replenishment to be performed at the
626	 * next firing of dl_timer.
627	 *
628	 * @dl_yielded tells if task gave up the CPU before consuming
629	 * all its available runtime during the last job.
630	 *
631	 * @dl_non_contending tells if the task is inactive while still
632	 * contributing to the active utilization. In other words, it
633	 * indicates if the inactive timer has been armed and its handler
634	 * has not been executed yet. This flag is useful to avoid race
635	 * conditions between the inactive timer handler and the wakeup
636	 * code.
637	 *
638	 * @dl_overrun tells if the task asked to be informed about runtime
639	 * overruns.
640	 */
641	unsigned int			dl_throttled      : 1;
642	unsigned int			dl_yielded        : 1;
643	unsigned int			dl_non_contending : 1;
644	unsigned int			dl_overrun	  : 1;
645	unsigned int			dl_server         : 1;
646
647	/*
648	 * Bandwidth enforcement timer. Each -deadline task has its
649	 * own bandwidth to be enforced, thus we need one timer per task.
650	 */
651	struct hrtimer			dl_timer;
652
653	/*
654	 * Inactive timer, responsible for decreasing the active utilization
655	 * at the "0-lag time". When a -deadline task blocks, it contributes
656	 * to GRUB's active utilization until the "0-lag time", hence a
657	 * timer is needed to decrease the active utilization at the correct
658	 * time.
659	 */
660	struct hrtimer			inactive_timer;
661
662	/*
663	 * Bits for DL-server functionality. Also see the comment near
664	 * dl_server_update().
665	 *
666	 * @rq the runqueue this server is for
667	 *
668	 * @server_has_tasks() returns true if @server_pick return a
669	 * runnable task.
670	 */
671	struct rq			*rq;
672	dl_server_has_tasks_f		server_has_tasks;
673	dl_server_pick_f		server_pick;
674
675#ifdef CONFIG_RT_MUTEXES
676	/*
677	 * Priority Inheritance. When a DEADLINE scheduling entity is boosted
678	 * pi_se points to the donor, otherwise points to the dl_se it belongs
679	 * to (the original one/itself).
680	 */
681	struct sched_dl_entity *pi_se;
682#endif
683};
684
685#ifdef CONFIG_UCLAMP_TASK
686/* Number of utilization clamp buckets (shorter alias) */
687#define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT
688
689/*
690 * Utilization clamp for a scheduling entity
691 * @value:		clamp value "assigned" to a se
692 * @bucket_id:		bucket index corresponding to the "assigned" value
693 * @active:		the se is currently refcounted in a rq's bucket
694 * @user_defined:	the requested clamp value comes from user-space
695 *
696 * The bucket_id is the index of the clamp bucket matching the clamp value
697 * which is pre-computed and stored to avoid expensive integer divisions from
698 * the fast path.
699 *
700 * The active bit is set whenever a task has got an "effective" value assigned,
701 * which can be different from the clamp value "requested" from user-space.
702 * This allows to know a task is refcounted in the rq's bucket corresponding
703 * to the "effective" bucket_id.
704 *
705 * The user_defined bit is set whenever a task has got a task-specific clamp
706 * value requested from userspace, i.e. the system defaults apply to this task
707 * just as a restriction. This allows to relax default clamps when a less
708 * restrictive task-specific value has been requested, thus allowing to
709 * implement a "nice" semantic. For example, a task running with a 20%
710 * default boost can still drop its own boosting to 0%.
711 */
712struct uclamp_se {
713	unsigned int value		: bits_per(SCHED_CAPACITY_SCALE);
714	unsigned int bucket_id		: bits_per(UCLAMP_BUCKETS);
715	unsigned int active		: 1;
716	unsigned int user_defined	: 1;
717};
718#endif /* CONFIG_UCLAMP_TASK */
719
720union rcu_special {
721	struct {
722		u8			blocked;
723		u8			need_qs;
724		u8			exp_hint; /* Hint for performance. */
725		u8			need_mb; /* Readers need smp_mb(). */
726	} b; /* Bits. */
727	u32 s; /* Set of bits. */
728};
729
730enum perf_event_task_context {
731	perf_invalid_context = -1,
732	perf_hw_context = 0,
733	perf_sw_context,
734	perf_nr_task_contexts,
735};
736
737struct wake_q_node {
738	struct wake_q_node *next;
739};
740
741struct kmap_ctrl {
742#ifdef CONFIG_KMAP_LOCAL
743	int				idx;
744	pte_t				pteval[KM_MAX_IDX];
745#endif
746};
747
748struct task_struct {
749#ifdef CONFIG_THREAD_INFO_IN_TASK
750	/*
751	 * For reasons of header soup (see current_thread_info()), this
752	 * must be the first element of task_struct.
753	 */
754	struct thread_info		thread_info;
755#endif
756	unsigned int			__state;
757
758	/* saved state for "spinlock sleepers" */
759	unsigned int			saved_state;
760
761	/*
762	 * This begins the randomizable portion of task_struct. Only
763	 * scheduling-critical items should be added above here.
764	 */
765	randomized_struct_fields_start
766
767	void				*stack;
768	refcount_t			usage;
769	/* Per task flags (PF_*), defined further below: */
770	unsigned int			flags;
771	unsigned int			ptrace;
772
773#ifdef CONFIG_SMP
774	int				on_cpu;
775	struct __call_single_node	wake_entry;
776	unsigned int			wakee_flips;
777	unsigned long			wakee_flip_decay_ts;
778	struct task_struct		*last_wakee;
779
780	/*
781	 * recent_used_cpu is initially set as the last CPU used by a task
782	 * that wakes affine another task. Waker/wakee relationships can
783	 * push tasks around a CPU where each wakeup moves to the next one.
784	 * Tracking a recently used CPU allows a quick search for a recently
785	 * used CPU that may be idle.
786	 */
787	int				recent_used_cpu;
788	int				wake_cpu;
789#endif
790	int				on_rq;
791
792	int				prio;
793	int				static_prio;
794	int				normal_prio;
795	unsigned int			rt_priority;
796
797	struct sched_entity		se;
798	struct sched_rt_entity		rt;
799	struct sched_dl_entity		dl;
800	struct sched_dl_entity		*dl_server;
801	const struct sched_class	*sched_class;
802
803#ifdef CONFIG_SCHED_CORE
804	struct rb_node			core_node;
805	unsigned long			core_cookie;
806	unsigned int			core_occupation;
807#endif
808
809#ifdef CONFIG_CGROUP_SCHED
810	struct task_group		*sched_task_group;
811#endif
812
813#ifdef CONFIG_UCLAMP_TASK
814	/*
815	 * Clamp values requested for a scheduling entity.
816	 * Must be updated with task_rq_lock() held.
817	 */
818	struct uclamp_se		uclamp_req[UCLAMP_CNT];
819	/*
820	 * Effective clamp values used for a scheduling entity.
821	 * Must be updated with task_rq_lock() held.
822	 */
823	struct uclamp_se		uclamp[UCLAMP_CNT];
824#endif
825
826	struct sched_statistics         stats;
827
828#ifdef CONFIG_PREEMPT_NOTIFIERS
829	/* List of struct preempt_notifier: */
830	struct hlist_head		preempt_notifiers;
831#endif
832
833#ifdef CONFIG_BLK_DEV_IO_TRACE
834	unsigned int			btrace_seq;
835#endif
836
837	unsigned int			policy;
838	int				nr_cpus_allowed;
839	const cpumask_t			*cpus_ptr;
840	cpumask_t			*user_cpus_ptr;
841	cpumask_t			cpus_mask;
842	void				*migration_pending;
843#ifdef CONFIG_SMP
844	unsigned short			migration_disabled;
845#endif
846	unsigned short			migration_flags;
847
848#ifdef CONFIG_PREEMPT_RCU
849	int				rcu_read_lock_nesting;
850	union rcu_special		rcu_read_unlock_special;
851	struct list_head		rcu_node_entry;
852	struct rcu_node			*rcu_blocked_node;
853#endif /* #ifdef CONFIG_PREEMPT_RCU */
854
855#ifdef CONFIG_TASKS_RCU
856	unsigned long			rcu_tasks_nvcsw;
857	u8				rcu_tasks_holdout;
858	u8				rcu_tasks_idx;
859	int				rcu_tasks_idle_cpu;
860	struct list_head		rcu_tasks_holdout_list;
861	int				rcu_tasks_exit_cpu;
862	struct list_head		rcu_tasks_exit_list;
863#endif /* #ifdef CONFIG_TASKS_RCU */
864
865#ifdef CONFIG_TASKS_TRACE_RCU
866	int				trc_reader_nesting;
867	int				trc_ipi_to_cpu;
868	union rcu_special		trc_reader_special;
869	struct list_head		trc_holdout_list;
870	struct list_head		trc_blkd_node;
871	int				trc_blkd_cpu;
872#endif /* #ifdef CONFIG_TASKS_TRACE_RCU */
873
874	struct sched_info		sched_info;
875
876	struct list_head		tasks;
877#ifdef CONFIG_SMP
878	struct plist_node		pushable_tasks;
879	struct rb_node			pushable_dl_tasks;
880#endif
881
882	struct mm_struct		*mm;
883	struct mm_struct		*active_mm;
884	struct address_space		*faults_disabled_mapping;
885
886	int				exit_state;
887	int				exit_code;
888	int				exit_signal;
889	/* The signal sent when the parent dies: */
890	int				pdeath_signal;
891	/* JOBCTL_*, siglock protected: */
892	unsigned long			jobctl;
893
894	/* Used for emulating ABI behavior of previous Linux versions: */
895	unsigned int			personality;
896
897	/* Scheduler bits, serialized by scheduler locks: */
898	unsigned			sched_reset_on_fork:1;
899	unsigned			sched_contributes_to_load:1;
900	unsigned			sched_migrated:1;
901
902	/* Force alignment to the next boundary: */
903	unsigned			:0;
904
905	/* Unserialized, strictly 'current' */
906
907	/*
908	 * This field must not be in the scheduler word above due to wakelist
909	 * queueing no longer being serialized by p->on_cpu. However:
910	 *
911	 * p->XXX = X;			ttwu()
912	 * schedule()			  if (p->on_rq && ..) // false
913	 *   smp_mb__after_spinlock();	  if (smp_load_acquire(&p->on_cpu) && //true
914	 *   deactivate_task()		      ttwu_queue_wakelist())
915	 *     p->on_rq = 0;			p->sched_remote_wakeup = Y;
916	 *
917	 * guarantees all stores of 'current' are visible before
918	 * ->sched_remote_wakeup gets used, so it can be in this word.
919	 */
920	unsigned			sched_remote_wakeup:1;
921#ifdef CONFIG_RT_MUTEXES
922	unsigned			sched_rt_mutex:1;
923#endif
924
925	/* Bit to tell TOMOYO we're in execve(): */
926	unsigned			in_execve:1;
927	unsigned			in_iowait:1;
928#ifndef TIF_RESTORE_SIGMASK
929	unsigned			restore_sigmask:1;
930#endif
931#ifdef CONFIG_MEMCG
932	unsigned			in_user_fault:1;
933#endif
934#ifdef CONFIG_LRU_GEN
935	/* whether the LRU algorithm may apply to this access */
936	unsigned			in_lru_fault:1;
937#endif
938#ifdef CONFIG_COMPAT_BRK
939	unsigned			brk_randomized:1;
940#endif
941#ifdef CONFIG_CGROUPS
942	/* disallow userland-initiated cgroup migration */
943	unsigned			no_cgroup_migration:1;
944	/* task is frozen/stopped (used by the cgroup freezer) */
945	unsigned			frozen:1;
946#endif
947#ifdef CONFIG_BLK_CGROUP
948	unsigned			use_memdelay:1;
949#endif
950#ifdef CONFIG_PSI
951	/* Stalled due to lack of memory */
952	unsigned			in_memstall:1;
953#endif
954#ifdef CONFIG_PAGE_OWNER
955	/* Used by page_owner=on to detect recursion in page tracking. */
956	unsigned			in_page_owner:1;
957#endif
958#ifdef CONFIG_EVENTFD
959	/* Recursion prevention for eventfd_signal() */
960	unsigned			in_eventfd:1;
961#endif
962#ifdef CONFIG_ARCH_HAS_CPU_PASID
963	unsigned			pasid_activated:1;
964#endif
965#ifdef	CONFIG_CPU_SUP_INTEL
966	unsigned			reported_split_lock:1;
967#endif
968#ifdef CONFIG_TASK_DELAY_ACCT
969	/* delay due to memory thrashing */
970	unsigned                        in_thrashing:1;
971#endif
972
973	unsigned long			atomic_flags; /* Flags requiring atomic access. */
974
975	struct restart_block		restart_block;
976
977	pid_t				pid;
978	pid_t				tgid;
979
980#ifdef CONFIG_STACKPROTECTOR
981	/* Canary value for the -fstack-protector GCC feature: */
982	unsigned long			stack_canary;
983#endif
984	/*
985	 * Pointers to the (original) parent process, youngest child, younger sibling,
986	 * older sibling, respectively.  (p->father can be replaced with
987	 * p->real_parent->pid)
988	 */
989
990	/* Real parent process: */
991	struct task_struct __rcu	*real_parent;
992
993	/* Recipient of SIGCHLD, wait4() reports: */
994	struct task_struct __rcu	*parent;
995
996	/*
997	 * Children/sibling form the list of natural children:
998	 */
999	struct list_head		children;
1000	struct list_head		sibling;
1001	struct task_struct		*group_leader;
1002
1003	/*
1004	 * 'ptraced' is the list of tasks this task is using ptrace() on.
1005	 *
1006	 * This includes both natural children and PTRACE_ATTACH targets.
1007	 * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
1008	 */
1009	struct list_head		ptraced;
1010	struct list_head		ptrace_entry;
1011
1012	/* PID/PID hash table linkage. */
1013	struct pid			*thread_pid;
1014	struct hlist_node		pid_links[PIDTYPE_MAX];
1015	struct list_head		thread_node;
1016
1017	struct completion		*vfork_done;
1018
1019	/* CLONE_CHILD_SETTID: */
1020	int __user			*set_child_tid;
1021
1022	/* CLONE_CHILD_CLEARTID: */
1023	int __user			*clear_child_tid;
1024
1025	/* PF_KTHREAD | PF_IO_WORKER */
1026	void				*worker_private;
1027
1028	u64				utime;
1029	u64				stime;
1030#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
1031	u64				utimescaled;
1032	u64				stimescaled;
1033#endif
1034	u64				gtime;
1035	struct prev_cputime		prev_cputime;
1036#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1037	struct vtime			vtime;
1038#endif
1039
1040#ifdef CONFIG_NO_HZ_FULL
1041	atomic_t			tick_dep_mask;
1042#endif
1043	/* Context switch counts: */
1044	unsigned long			nvcsw;
1045	unsigned long			nivcsw;
1046
1047	/* Monotonic time in nsecs: */
1048	u64				start_time;
1049
1050	/* Boot based time in nsecs: */
1051	u64				start_boottime;
1052
1053	/* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
1054	unsigned long			min_flt;
1055	unsigned long			maj_flt;
1056
1057	/* Empty if CONFIG_POSIX_CPUTIMERS=n */
1058	struct posix_cputimers		posix_cputimers;
1059
1060#ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK
1061	struct posix_cputimers_work	posix_cputimers_work;
1062#endif
1063
1064	/* Process credentials: */
1065
1066	/* Tracer's credentials at attach: */
1067	const struct cred __rcu		*ptracer_cred;
1068
1069	/* Objective and real subjective task credentials (COW): */
1070	const struct cred __rcu		*real_cred;
1071
1072	/* Effective (overridable) subjective task credentials (COW): */
1073	const struct cred __rcu		*cred;
1074
1075#ifdef CONFIG_KEYS
1076	/* Cached requested key. */
1077	struct key			*cached_requested_key;
1078#endif
1079
1080	/*
1081	 * executable name, excluding path.
1082	 *
1083	 * - normally initialized setup_new_exec()
1084	 * - access it with [gs]et_task_comm()
1085	 * - lock it with task_lock()
1086	 */
1087	char				comm[TASK_COMM_LEN];
1088
1089	struct nameidata		*nameidata;
1090
1091#ifdef CONFIG_SYSVIPC
1092	struct sysv_sem			sysvsem;
1093	struct sysv_shm			sysvshm;
1094#endif
1095#ifdef CONFIG_DETECT_HUNG_TASK
1096	unsigned long			last_switch_count;
1097	unsigned long			last_switch_time;
1098#endif
1099	/* Filesystem information: */
1100	struct fs_struct		*fs;
1101
1102	/* Open file information: */
1103	struct files_struct		*files;
1104
1105#ifdef CONFIG_IO_URING
1106	struct io_uring_task		*io_uring;
1107#endif
1108
1109	/* Namespaces: */
1110	struct nsproxy			*nsproxy;
1111
1112	/* Signal handlers: */
1113	struct signal_struct		*signal;
1114	struct sighand_struct __rcu		*sighand;
1115	sigset_t			blocked;
1116	sigset_t			real_blocked;
1117	/* Restored if set_restore_sigmask() was used: */
1118	sigset_t			saved_sigmask;
1119	struct sigpending		pending;
1120	unsigned long			sas_ss_sp;
1121	size_t				sas_ss_size;
1122	unsigned int			sas_ss_flags;
1123
1124	struct callback_head		*task_works;
1125
1126#ifdef CONFIG_AUDIT
1127#ifdef CONFIG_AUDITSYSCALL
1128	struct audit_context		*audit_context;
1129#endif
1130	kuid_t				loginuid;
1131	unsigned int			sessionid;
1132#endif
1133	struct seccomp			seccomp;
1134	struct syscall_user_dispatch	syscall_dispatch;
1135
1136	/* Thread group tracking: */
1137	u64				parent_exec_id;
1138	u64				self_exec_id;
1139
1140	/* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
1141	spinlock_t			alloc_lock;
1142
1143	/* Protection of the PI data structures: */
1144	raw_spinlock_t			pi_lock;
1145
1146	struct wake_q_node		wake_q;
1147
1148#ifdef CONFIG_RT_MUTEXES
1149	/* PI waiters blocked on a rt_mutex held by this task: */
1150	struct rb_root_cached		pi_waiters;
1151	/* Updated under owner's pi_lock and rq lock */
1152	struct task_struct		*pi_top_task;
1153	/* Deadlock detection and priority inheritance handling: */
1154	struct rt_mutex_waiter		*pi_blocked_on;
1155#endif
1156
1157#ifdef CONFIG_DEBUG_MUTEXES
1158	/* Mutex deadlock detection: */
1159	struct mutex_waiter		*blocked_on;
1160#endif
1161
1162#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1163	int				non_block_count;
1164#endif
1165
1166#ifdef CONFIG_TRACE_IRQFLAGS
1167	struct irqtrace_events		irqtrace;
1168	unsigned int			hardirq_threaded;
1169	u64				hardirq_chain_key;
1170	int				softirqs_enabled;
1171	int				softirq_context;
1172	int				irq_config;
1173#endif
1174#ifdef CONFIG_PREEMPT_RT
1175	int				softirq_disable_cnt;
1176#endif
1177
1178#ifdef CONFIG_LOCKDEP
1179# define MAX_LOCK_DEPTH			48UL
1180	u64				curr_chain_key;
1181	int				lockdep_depth;
1182	unsigned int			lockdep_recursion;
1183	struct held_lock		held_locks[MAX_LOCK_DEPTH];
1184#endif
1185
1186#if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP)
1187	unsigned int			in_ubsan;
1188#endif
1189
1190	/* Journalling filesystem info: */
1191	void				*journal_info;
1192
1193	/* Stacked block device info: */
1194	struct bio_list			*bio_list;
1195
1196	/* Stack plugging: */
1197	struct blk_plug			*plug;
1198
1199	/* VM state: */
1200	struct reclaim_state		*reclaim_state;
1201
1202	struct io_context		*io_context;
1203
1204#ifdef CONFIG_COMPACTION
1205	struct capture_control		*capture_control;
1206#endif
1207	/* Ptrace state: */
1208	unsigned long			ptrace_message;
1209	kernel_siginfo_t		*last_siginfo;
1210
1211	struct task_io_accounting	ioac;
1212#ifdef CONFIG_PSI
1213	/* Pressure stall state */
1214	unsigned int			psi_flags;
1215#endif
1216#ifdef CONFIG_TASK_XACCT
1217	/* Accumulated RSS usage: */
1218	u64				acct_rss_mem1;
1219	/* Accumulated virtual memory usage: */
1220	u64				acct_vm_mem1;
1221	/* stime + utime since last update: */
1222	u64				acct_timexpd;
1223#endif
1224#ifdef CONFIG_CPUSETS
1225	/* Protected by ->alloc_lock: */
1226	nodemask_t			mems_allowed;
1227	/* Sequence number to catch updates: */
1228	seqcount_spinlock_t		mems_allowed_seq;
1229	int				cpuset_mem_spread_rotor;
1230	int				cpuset_slab_spread_rotor;
1231#endif
1232#ifdef CONFIG_CGROUPS
1233	/* Control Group info protected by css_set_lock: */
1234	struct css_set __rcu		*cgroups;
1235	/* cg_list protected by css_set_lock and tsk->alloc_lock: */
1236	struct list_head		cg_list;
1237#endif
1238#ifdef CONFIG_X86_CPU_RESCTRL
1239	u32				closid;
1240	u32				rmid;
1241#endif
1242#ifdef CONFIG_FUTEX
1243	struct robust_list_head __user	*robust_list;
1244#ifdef CONFIG_COMPAT
1245	struct compat_robust_list_head __user *compat_robust_list;
1246#endif
1247	struct list_head		pi_state_list;
1248	struct futex_pi_state		*pi_state_cache;
1249	struct mutex			futex_exit_mutex;
1250	unsigned int			futex_state;
1251#endif
1252#ifdef CONFIG_PERF_EVENTS
1253	struct perf_event_context	*perf_event_ctxp;
1254	struct mutex			perf_event_mutex;
1255	struct list_head		perf_event_list;
1256#endif
1257#ifdef CONFIG_DEBUG_PREEMPT
1258	unsigned long			preempt_disable_ip;
1259#endif
1260#ifdef CONFIG_NUMA
1261	/* Protected by alloc_lock: */
1262	struct mempolicy		*mempolicy;
1263	short				il_prev;
1264	u8				il_weight;
1265	short				pref_node_fork;
1266#endif
1267#ifdef CONFIG_NUMA_BALANCING
1268	int				numa_scan_seq;
1269	unsigned int			numa_scan_period;
1270	unsigned int			numa_scan_period_max;
1271	int				numa_preferred_nid;
1272	unsigned long			numa_migrate_retry;
1273	/* Migration stamp: */
1274	u64				node_stamp;
1275	u64				last_task_numa_placement;
1276	u64				last_sum_exec_runtime;
1277	struct callback_head		numa_work;
1278
1279	/*
1280	 * This pointer is only modified for current in syscall and
1281	 * pagefault context (and for tasks being destroyed), so it can be read
1282	 * from any of the following contexts:
1283	 *  - RCU read-side critical section
1284	 *  - current->numa_group from everywhere
1285	 *  - task's runqueue locked, task not running
1286	 */
1287	struct numa_group __rcu		*numa_group;
1288
1289	/*
1290	 * numa_faults is an array split into four regions:
1291	 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1292	 * in this precise order.
1293	 *
1294	 * faults_memory: Exponential decaying average of faults on a per-node
1295	 * basis. Scheduling placement decisions are made based on these
1296	 * counts. The values remain static for the duration of a PTE scan.
1297	 * faults_cpu: Track the nodes the process was running on when a NUMA
1298	 * hinting fault was incurred.
1299	 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1300	 * during the current scan window. When the scan completes, the counts
1301	 * in faults_memory and faults_cpu decay and these values are copied.
1302	 */
1303	unsigned long			*numa_faults;
1304	unsigned long			total_numa_faults;
1305
1306	/*
1307	 * numa_faults_locality tracks if faults recorded during the last
1308	 * scan window were remote/local or failed to migrate. The task scan
1309	 * period is adapted based on the locality of the faults with different
1310	 * weights depending on whether they were shared or private faults
1311	 */
1312	unsigned long			numa_faults_locality[3];
1313
1314	unsigned long			numa_pages_migrated;
1315#endif /* CONFIG_NUMA_BALANCING */
1316
1317#ifdef CONFIG_RSEQ
1318	struct rseq __user *rseq;
1319	u32 rseq_len;
1320	u32 rseq_sig;
1321	/*
1322	 * RmW on rseq_event_mask must be performed atomically
1323	 * with respect to preemption.
1324	 */
1325	unsigned long rseq_event_mask;
1326#endif
1327
1328#ifdef CONFIG_SCHED_MM_CID
1329	int				mm_cid;		/* Current cid in mm */
1330	int				last_mm_cid;	/* Most recent cid in mm */
1331	int				migrate_from_cpu;
1332	int				mm_cid_active;	/* Whether cid bitmap is active */
1333	struct callback_head		cid_work;
1334#endif
1335
1336	struct tlbflush_unmap_batch	tlb_ubc;
1337
1338	/* Cache last used pipe for splice(): */
1339	struct pipe_inode_info		*splice_pipe;
1340
1341	struct page_frag		task_frag;
1342
1343#ifdef CONFIG_TASK_DELAY_ACCT
1344	struct task_delay_info		*delays;
1345#endif
1346
1347#ifdef CONFIG_FAULT_INJECTION
1348	int				make_it_fail;
1349	unsigned int			fail_nth;
1350#endif
1351	/*
1352	 * When (nr_dirtied >= nr_dirtied_pause), it's time to call
1353	 * balance_dirty_pages() for a dirty throttling pause:
1354	 */
1355	int				nr_dirtied;
1356	int				nr_dirtied_pause;
1357	/* Start of a write-and-pause period: */
1358	unsigned long			dirty_paused_when;
1359
1360#ifdef CONFIG_LATENCYTOP
1361	int				latency_record_count;
1362	struct latency_record		latency_record[LT_SAVECOUNT];
1363#endif
1364	/*
1365	 * Time slack values; these are used to round up poll() and
1366	 * select() etc timeout values. These are in nanoseconds.
1367	 */
1368	u64				timer_slack_ns;
1369	u64				default_timer_slack_ns;
1370
1371#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
1372	unsigned int			kasan_depth;
1373#endif
1374
1375#ifdef CONFIG_KCSAN
1376	struct kcsan_ctx		kcsan_ctx;
1377#ifdef CONFIG_TRACE_IRQFLAGS
1378	struct irqtrace_events		kcsan_save_irqtrace;
1379#endif
1380#ifdef CONFIG_KCSAN_WEAK_MEMORY
1381	int				kcsan_stack_depth;
1382#endif
1383#endif
1384
1385#ifdef CONFIG_KMSAN
1386	struct kmsan_ctx		kmsan_ctx;
1387#endif
1388
1389#if IS_ENABLED(CONFIG_KUNIT)
1390	struct kunit			*kunit_test;
1391#endif
1392
1393#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1394	/* Index of current stored address in ret_stack: */
1395	int				curr_ret_stack;
1396	int				curr_ret_depth;
1397
1398	/* Stack of return addresses for return function tracing: */
1399	struct ftrace_ret_stack		*ret_stack;
1400
1401	/* Timestamp for last schedule: */
1402	unsigned long long		ftrace_timestamp;
1403
1404	/*
1405	 * Number of functions that haven't been traced
1406	 * because of depth overrun:
1407	 */
1408	atomic_t			trace_overrun;
1409
1410	/* Pause tracing: */
1411	atomic_t			tracing_graph_pause;
1412#endif
1413
1414#ifdef CONFIG_TRACING
1415	/* Bitmask and counter of trace recursion: */
1416	unsigned long			trace_recursion;
1417#endif /* CONFIG_TRACING */
1418
1419#ifdef CONFIG_KCOV
1420	/* See kernel/kcov.c for more details. */
1421
1422	/* Coverage collection mode enabled for this task (0 if disabled): */
1423	unsigned int			kcov_mode;
1424
1425	/* Size of the kcov_area: */
1426	unsigned int			kcov_size;
1427
1428	/* Buffer for coverage collection: */
1429	void				*kcov_area;
1430
1431	/* KCOV descriptor wired with this task or NULL: */
1432	struct kcov			*kcov;
1433
1434	/* KCOV common handle for remote coverage collection: */
1435	u64				kcov_handle;
1436
1437	/* KCOV sequence number: */
1438	int				kcov_sequence;
1439
1440	/* Collect coverage from softirq context: */
1441	unsigned int			kcov_softirq;
1442#endif
1443
1444#ifdef CONFIG_MEMCG
1445	struct mem_cgroup		*memcg_in_oom;
1446	gfp_t				memcg_oom_gfp_mask;
1447	int				memcg_oom_order;
1448
1449	/* Number of pages to reclaim on returning to userland: */
1450	unsigned int			memcg_nr_pages_over_high;
1451
1452	/* Used by memcontrol for targeted memcg charge: */
1453	struct mem_cgroup		*active_memcg;
1454#endif
1455
1456#ifdef CONFIG_MEMCG_KMEM
1457	struct obj_cgroup		*objcg;
1458#endif
1459
1460#ifdef CONFIG_BLK_CGROUP
1461	struct gendisk			*throttle_disk;
1462#endif
1463
1464#ifdef CONFIG_UPROBES
1465	struct uprobe_task		*utask;
1466#endif
1467#if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1468	unsigned int			sequential_io;
1469	unsigned int			sequential_io_avg;
1470#endif
1471	struct kmap_ctrl		kmap_ctrl;
1472#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1473	unsigned long			task_state_change;
1474# ifdef CONFIG_PREEMPT_RT
1475	unsigned long			saved_state_change;
1476# endif
1477#endif
1478	struct rcu_head			rcu;
1479	refcount_t			rcu_users;
1480	int				pagefault_disabled;
1481#ifdef CONFIG_MMU
1482	struct task_struct		*oom_reaper_list;
1483	struct timer_list		oom_reaper_timer;
1484#endif
1485#ifdef CONFIG_VMAP_STACK
1486	struct vm_struct		*stack_vm_area;
1487#endif
1488#ifdef CONFIG_THREAD_INFO_IN_TASK
1489	/* A live task holds one reference: */
1490	refcount_t			stack_refcount;
1491#endif
1492#ifdef CONFIG_LIVEPATCH
1493	int patch_state;
1494#endif
1495#ifdef CONFIG_SECURITY
1496	/* Used by LSM modules for access restriction: */
1497	void				*security;
1498#endif
1499#ifdef CONFIG_BPF_SYSCALL
1500	/* Used by BPF task local storage */
1501	struct bpf_local_storage __rcu	*bpf_storage;
1502	/* Used for BPF run context */
1503	struct bpf_run_ctx		*bpf_ctx;
1504#endif
1505
1506#ifdef CONFIG_GCC_PLUGIN_STACKLEAK
1507	unsigned long			lowest_stack;
1508	unsigned long			prev_lowest_stack;
1509#endif
1510
1511#ifdef CONFIG_X86_MCE
1512	void __user			*mce_vaddr;
1513	__u64				mce_kflags;
1514	u64				mce_addr;
1515	__u64				mce_ripv : 1,
1516					mce_whole_page : 1,
1517					__mce_reserved : 62;
1518	struct callback_head		mce_kill_me;
1519	int				mce_count;
1520#endif
1521
1522#ifdef CONFIG_KRETPROBES
1523	struct llist_head               kretprobe_instances;
1524#endif
1525#ifdef CONFIG_RETHOOK
1526	struct llist_head               rethooks;
1527#endif
1528
1529#ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH
1530	/*
1531	 * If L1D flush is supported on mm context switch
1532	 * then we use this callback head to queue kill work
1533	 * to kill tasks that are not running on SMT disabled
1534	 * cores
1535	 */
1536	struct callback_head		l1d_flush_kill;
1537#endif
1538
1539#ifdef CONFIG_RV
1540	/*
1541	 * Per-task RV monitor. Nowadays fixed in RV_PER_TASK_MONITORS.
1542	 * If we find justification for more monitors, we can think
1543	 * about adding more or developing a dynamic method. So far,
1544	 * none of these are justified.
1545	 */
1546	union rv_task_monitor		rv[RV_PER_TASK_MONITORS];
1547#endif
1548
1549#ifdef CONFIG_USER_EVENTS
1550	struct user_event_mm		*user_event_mm;
1551#endif
1552
1553	/*
1554	 * New fields for task_struct should be added above here, so that
1555	 * they are included in the randomized portion of task_struct.
1556	 */
1557	randomized_struct_fields_end
1558
1559	/* CPU-specific state of this task: */
1560	struct thread_struct		thread;
1561
1562	/*
1563	 * WARNING: on x86, 'thread_struct' contains a variable-sized
1564	 * structure.  It *MUST* be at the end of 'task_struct'.
1565	 *
1566	 * Do not put anything below here!
1567	 */
1568};
1569
1570#define TASK_REPORT_IDLE	(TASK_REPORT + 1)
1571#define TASK_REPORT_MAX		(TASK_REPORT_IDLE << 1)
1572
1573static inline unsigned int __task_state_index(unsigned int tsk_state,
1574					      unsigned int tsk_exit_state)
1575{
1576	unsigned int state = (tsk_state | tsk_exit_state) & TASK_REPORT;
1577
1578	BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);
1579
1580	if ((tsk_state & TASK_IDLE) == TASK_IDLE)
1581		state = TASK_REPORT_IDLE;
1582
1583	/*
1584	 * We're lying here, but rather than expose a completely new task state
1585	 * to userspace, we can make this appear as if the task has gone through
1586	 * a regular rt_mutex_lock() call.
1587	 */
1588	if (tsk_state & TASK_RTLOCK_WAIT)
1589		state = TASK_UNINTERRUPTIBLE;
1590
1591	return fls(state);
1592}
1593
1594static inline unsigned int task_state_index(struct task_struct *tsk)
1595{
1596	return __task_state_index(READ_ONCE(tsk->__state), tsk->exit_state);
1597}
1598
1599static inline char task_index_to_char(unsigned int state)
1600{
1601	static const char state_char[] = "RSDTtXZPI";
1602
1603	BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1);
1604
1605	return state_char[state];
1606}
1607
1608static inline char task_state_to_char(struct task_struct *tsk)
1609{
1610	return task_index_to_char(task_state_index(tsk));
1611}
1612
1613extern struct pid *cad_pid;
1614
1615/*
1616 * Per process flags
1617 */
1618#define PF_VCPU			0x00000001	/* I'm a virtual CPU */
1619#define PF_IDLE			0x00000002	/* I am an IDLE thread */
1620#define PF_EXITING		0x00000004	/* Getting shut down */
1621#define PF_POSTCOREDUMP		0x00000008	/* Coredumps should ignore this task */
1622#define PF_IO_WORKER		0x00000010	/* Task is an IO worker */
1623#define PF_WQ_WORKER		0x00000020	/* I'm a workqueue worker */
1624#define PF_FORKNOEXEC		0x00000040	/* Forked but didn't exec */
1625#define PF_MCE_PROCESS		0x00000080      /* Process policy on mce errors */
1626#define PF_SUPERPRIV		0x00000100	/* Used super-user privileges */
1627#define PF_DUMPCORE		0x00000200	/* Dumped core */
1628#define PF_SIGNALED		0x00000400	/* Killed by a signal */
1629#define PF_MEMALLOC		0x00000800	/* Allocating memory to free memory. See memalloc_noreclaim_save() */
1630#define PF_NPROC_EXCEEDED	0x00001000	/* set_user() noticed that RLIMIT_NPROC was exceeded */
1631#define PF_USED_MATH		0x00002000	/* If unset the fpu must be initialized before use */
1632#define PF_USER_WORKER		0x00004000	/* Kernel thread cloned from userspace thread */
1633#define PF_NOFREEZE		0x00008000	/* This thread should not be frozen */
1634#define PF__HOLE__00010000	0x00010000
1635#define PF_KSWAPD		0x00020000	/* I am kswapd */
1636#define PF_MEMALLOC_NOFS	0x00040000	/* All allocations inherit GFP_NOFS. See memalloc_nfs_save() */
1637#define PF_MEMALLOC_NOIO	0x00080000	/* All allocations inherit GFP_NOIO. See memalloc_noio_save() */
1638#define PF_LOCAL_THROTTLE	0x00100000	/* Throttle writes only against the bdi I write to,
1639						 * I am cleaning dirty pages from some other bdi. */
1640#define PF_KTHREAD		0x00200000	/* I am a kernel thread */
1641#define PF_RANDOMIZE		0x00400000	/* Randomize virtual address space */
1642#define PF_MEMALLOC_NORECLAIM	0x00800000	/* All allocation requests will clear __GFP_DIRECT_RECLAIM */
1643#define PF_MEMALLOC_NOWARN	0x01000000	/* All allocation requests will inherit __GFP_NOWARN */
1644#define PF__HOLE__02000000	0x02000000
1645#define PF_NO_SETAFFINITY	0x04000000	/* Userland is not allowed to meddle with cpus_mask */
1646#define PF_MCE_EARLY		0x08000000      /* Early kill for mce process policy */
1647#define PF_MEMALLOC_PIN		0x10000000	/* Allocations constrained to zones which allow long term pinning.
1648						 * See memalloc_pin_save() */
1649#define PF_BLOCK_TS		0x20000000	/* plug has ts that needs updating */
1650#define PF__HOLE__40000000	0x40000000
1651#define PF_SUSPEND_TASK		0x80000000      /* This thread called freeze_processes() and should not be frozen */
1652
1653/*
1654 * Only the _current_ task can read/write to tsk->flags, but other
1655 * tasks can access tsk->flags in readonly mode for example
1656 * with tsk_used_math (like during threaded core dumping).
1657 * There is however an exception to this rule during ptrace
1658 * or during fork: the ptracer task is allowed to write to the
1659 * child->flags of its traced child (same goes for fork, the parent
1660 * can write to the child->flags), because we're guaranteed the
1661 * child is not running and in turn not changing child->flags
1662 * at the same time the parent does it.
1663 */
1664#define clear_stopped_child_used_math(child)	do { (child)->flags &= ~PF_USED_MATH; } while (0)
1665#define set_stopped_child_used_math(child)	do { (child)->flags |= PF_USED_MATH; } while (0)
1666#define clear_used_math()			clear_stopped_child_used_math(current)
1667#define set_used_math()				set_stopped_child_used_math(current)
1668
1669#define conditional_stopped_child_used_math(condition, child) \
1670	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1671
1672#define conditional_used_math(condition)	conditional_stopped_child_used_math(condition, current)
1673
1674#define copy_to_stopped_child_used_math(child) \
1675	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1676
1677/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1678#define tsk_used_math(p)			((p)->flags & PF_USED_MATH)
1679#define used_math()				tsk_used_math(current)
1680
1681static __always_inline bool is_percpu_thread(void)
1682{
1683#ifdef CONFIG_SMP
1684	return (current->flags & PF_NO_SETAFFINITY) &&
1685		(current->nr_cpus_allowed  == 1);
1686#else
1687	return true;
1688#endif
1689}
1690
1691/* Per-process atomic flags. */
1692#define PFA_NO_NEW_PRIVS		0	/* May not gain new privileges. */
1693#define PFA_SPREAD_PAGE			1	/* Spread page cache over cpuset */
1694#define PFA_SPREAD_SLAB			2	/* Spread some slab caches over cpuset */
1695#define PFA_SPEC_SSB_DISABLE		3	/* Speculative Store Bypass disabled */
1696#define PFA_SPEC_SSB_FORCE_DISABLE	4	/* Speculative Store Bypass force disabled*/
1697#define PFA_SPEC_IB_DISABLE		5	/* Indirect branch speculation restricted */
1698#define PFA_SPEC_IB_FORCE_DISABLE	6	/* Indirect branch speculation permanently restricted */
1699#define PFA_SPEC_SSB_NOEXEC		7	/* Speculative Store Bypass clear on execve() */
1700
1701#define TASK_PFA_TEST(name, func)					\
1702	static inline bool task_##func(struct task_struct *p)		\
1703	{ return test_bit(PFA_##name, &p->atomic_flags); }
1704
1705#define TASK_PFA_SET(name, func)					\
1706	static inline void task_set_##func(struct task_struct *p)	\
1707	{ set_bit(PFA_##name, &p->atomic_flags); }
1708
1709#define TASK_PFA_CLEAR(name, func)					\
1710	static inline void task_clear_##func(struct task_struct *p)	\
1711	{ clear_bit(PFA_##name, &p->atomic_flags); }
1712
1713TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1714TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1715
1716TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1717TASK_PFA_SET(SPREAD_PAGE, spread_page)
1718TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
1719
1720TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
1721TASK_PFA_SET(SPREAD_SLAB, spread_slab)
1722TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1723
1724TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable)
1725TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable)
1726TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable)
1727
1728TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1729TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1730TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1731
1732TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1733TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1734
1735TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable)
1736TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable)
1737TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable)
1738
1739TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1740TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1741
1742static inline void
1743current_restore_flags(unsigned long orig_flags, unsigned long flags)
1744{
1745	current->flags &= ~flags;
1746	current->flags |= orig_flags & flags;
1747}
1748
1749extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
1750extern int task_can_attach(struct task_struct *p);
1751extern int dl_bw_alloc(int cpu, u64 dl_bw);
1752extern void dl_bw_free(int cpu, u64 dl_bw);
1753#ifdef CONFIG_SMP
1754
1755/* do_set_cpus_allowed() - consider using set_cpus_allowed_ptr() instead */
1756extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask);
1757
1758/**
1759 * set_cpus_allowed_ptr - set CPU affinity mask of a task
1760 * @p: the task
1761 * @new_mask: CPU affinity mask
1762 *
1763 * Return: zero if successful, or a negative error code
1764 */
1765extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
1766extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node);
1767extern void release_user_cpus_ptr(struct task_struct *p);
1768extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask);
1769extern void force_compatible_cpus_allowed_ptr(struct task_struct *p);
1770extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p);
1771#else
1772static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
1773{
1774}
1775static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
1776{
1777	if (!cpumask_test_cpu(0, new_mask))
1778		return -EINVAL;
1779	return 0;
1780}
1781static inline int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node)
1782{
1783	if (src->user_cpus_ptr)
1784		return -EINVAL;
1785	return 0;
1786}
1787static inline void release_user_cpus_ptr(struct task_struct *p)
1788{
1789	WARN_ON(p->user_cpus_ptr);
1790}
1791
1792static inline int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask)
1793{
1794	return 0;
1795}
1796#endif
1797
1798extern int yield_to(struct task_struct *p, bool preempt);
1799extern void set_user_nice(struct task_struct *p, long nice);
1800extern int task_prio(const struct task_struct *p);
1801
1802/**
1803 * task_nice - return the nice value of a given task.
1804 * @p: the task in question.
1805 *
1806 * Return: The nice value [ -20 ... 0 ... 19 ].
1807 */
1808static inline int task_nice(const struct task_struct *p)
1809{
1810	return PRIO_TO_NICE((p)->static_prio);
1811}
1812
1813extern int can_nice(const struct task_struct *p, const int nice);
1814extern int task_curr(const struct task_struct *p);
1815extern int idle_cpu(int cpu);
1816extern int available_idle_cpu(int cpu);
1817extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
1818extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
1819extern void sched_set_fifo(struct task_struct *p);
1820extern void sched_set_fifo_low(struct task_struct *p);
1821extern void sched_set_normal(struct task_struct *p, int nice);
1822extern int sched_setattr(struct task_struct *, const struct sched_attr *);
1823extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *);
1824extern struct task_struct *idle_task(int cpu);
1825
1826/**
1827 * is_idle_task - is the specified task an idle task?
1828 * @p: the task in question.
1829 *
1830 * Return: 1 if @p is an idle task. 0 otherwise.
1831 */
1832static __always_inline bool is_idle_task(const struct task_struct *p)
1833{
1834	return !!(p->flags & PF_IDLE);
1835}
1836
1837extern struct task_struct *curr_task(int cpu);
1838extern void ia64_set_curr_task(int cpu, struct task_struct *p);
1839
1840void yield(void);
1841
1842union thread_union {
1843	struct task_struct task;
1844#ifndef CONFIG_THREAD_INFO_IN_TASK
1845	struct thread_info thread_info;
1846#endif
1847	unsigned long stack[THREAD_SIZE/sizeof(long)];
1848};
1849
1850#ifndef CONFIG_THREAD_INFO_IN_TASK
1851extern struct thread_info init_thread_info;
1852#endif
1853
1854extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];
1855
1856#ifdef CONFIG_THREAD_INFO_IN_TASK
1857# define task_thread_info(task)	(&(task)->thread_info)
1858#elif !defined(__HAVE_THREAD_FUNCTIONS)
1859# define task_thread_info(task)	((struct thread_info *)(task)->stack)
1860#endif
1861
1862/*
1863 * find a task by one of its numerical ids
1864 *
1865 * find_task_by_pid_ns():
1866 *      finds a task by its pid in the specified namespace
1867 * find_task_by_vpid():
1868 *      finds a task by its virtual pid
1869 *
1870 * see also find_vpid() etc in include/linux/pid.h
1871 */
1872
1873extern struct task_struct *find_task_by_vpid(pid_t nr);
1874extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns);
1875
1876/*
1877 * find a task by its virtual pid and get the task struct
1878 */
1879extern struct task_struct *find_get_task_by_vpid(pid_t nr);
1880
1881extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1882extern int wake_up_process(struct task_struct *tsk);
1883extern void wake_up_new_task(struct task_struct *tsk);
1884
1885#ifdef CONFIG_SMP
1886extern void kick_process(struct task_struct *tsk);
1887#else
1888static inline void kick_process(struct task_struct *tsk) { }
1889#endif
1890
1891extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
1892
1893static inline void set_task_comm(struct task_struct *tsk, const char *from)
1894{
1895	__set_task_comm(tsk, from, false);
1896}
1897
1898extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk);
1899#define get_task_comm(buf, tsk) ({			\
1900	BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN);	\
1901	__get_task_comm(buf, sizeof(buf), tsk);		\
1902})
1903
1904#ifdef CONFIG_SMP
1905static __always_inline void scheduler_ipi(void)
1906{
1907	/*
1908	 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting
1909	 * TIF_NEED_RESCHED remotely (for the first time) will also send
1910	 * this IPI.
1911	 */
1912	preempt_fold_need_resched();
1913}
1914#else
1915static inline void scheduler_ipi(void) { }
1916#endif
1917
1918extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state);
1919
1920/*
1921 * Set thread flags in other task's structures.
1922 * See asm/thread_info.h for TIF_xxxx flags available:
1923 */
1924static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1925{
1926	set_ti_thread_flag(task_thread_info(tsk), flag);
1927}
1928
1929static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1930{
1931	clear_ti_thread_flag(task_thread_info(tsk), flag);
1932}
1933
1934static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag,
1935					  bool value)
1936{
1937	update_ti_thread_flag(task_thread_info(tsk), flag, value);
1938}
1939
1940static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1941{
1942	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1943}
1944
1945static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1946{
1947	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1948}
1949
1950static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1951{
1952	return test_ti_thread_flag(task_thread_info(tsk), flag);
1953}
1954
1955static inline void set_tsk_need_resched(struct task_struct *tsk)
1956{
1957	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1958}
1959
1960static inline void clear_tsk_need_resched(struct task_struct *tsk)
1961{
1962	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1963}
1964
1965static inline int test_tsk_need_resched(struct task_struct *tsk)
1966{
1967	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
1968}
1969
1970/*
1971 * cond_resched() and cond_resched_lock(): latency reduction via
1972 * explicit rescheduling in places that are safe. The return
1973 * value indicates whether a reschedule was done in fact.
1974 * cond_resched_lock() will drop the spinlock before scheduling,
1975 */
1976#if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC)
1977extern int __cond_resched(void);
1978
1979#if defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL)
1980
1981void sched_dynamic_klp_enable(void);
1982void sched_dynamic_klp_disable(void);
1983
1984DECLARE_STATIC_CALL(cond_resched, __cond_resched);
1985
1986static __always_inline int _cond_resched(void)
1987{
1988	return static_call_mod(cond_resched)();
1989}
1990
1991#elif defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY)
1992
1993extern int dynamic_cond_resched(void);
1994
1995static __always_inline int _cond_resched(void)
1996{
1997	return dynamic_cond_resched();
1998}
1999
2000#else /* !CONFIG_PREEMPTION */
2001
2002static inline int _cond_resched(void)
2003{
2004	klp_sched_try_switch();
2005	return __cond_resched();
2006}
2007
2008#endif /* PREEMPT_DYNAMIC && CONFIG_HAVE_PREEMPT_DYNAMIC_CALL */
2009
2010#else /* CONFIG_PREEMPTION && !CONFIG_PREEMPT_DYNAMIC */
2011
2012static inline int _cond_resched(void)
2013{
2014	klp_sched_try_switch();
2015	return 0;
2016}
2017
2018#endif /* !CONFIG_PREEMPTION || CONFIG_PREEMPT_DYNAMIC */
2019
2020#define cond_resched() ({			\
2021	__might_resched(__FILE__, __LINE__, 0);	\
2022	_cond_resched();			\
2023})
2024
2025extern int __cond_resched_lock(spinlock_t *lock);
2026extern int __cond_resched_rwlock_read(rwlock_t *lock);
2027extern int __cond_resched_rwlock_write(rwlock_t *lock);
2028
2029#define MIGHT_RESCHED_RCU_SHIFT		8
2030#define MIGHT_RESCHED_PREEMPT_MASK	((1U << MIGHT_RESCHED_RCU_SHIFT) - 1)
2031
2032#ifndef CONFIG_PREEMPT_RT
2033/*
2034 * Non RT kernels have an elevated preempt count due to the held lock,
2035 * but are not allowed to be inside a RCU read side critical section
2036 */
2037# define PREEMPT_LOCK_RESCHED_OFFSETS	PREEMPT_LOCK_OFFSET
2038#else
2039/*
2040 * spin/rw_lock() on RT implies rcu_read_lock(). The might_sleep() check in
2041 * cond_resched*lock() has to take that into account because it checks for
2042 * preempt_count() and rcu_preempt_depth().
2043 */
2044# define PREEMPT_LOCK_RESCHED_OFFSETS	\
2045	(PREEMPT_LOCK_OFFSET + (1U << MIGHT_RESCHED_RCU_SHIFT))
2046#endif
2047
2048#define cond_resched_lock(lock) ({						\
2049	__might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS);	\
2050	__cond_resched_lock(lock);						\
2051})
2052
2053#define cond_resched_rwlock_read(lock) ({					\
2054	__might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS);	\
2055	__cond_resched_rwlock_read(lock);					\
2056})
2057
2058#define cond_resched_rwlock_write(lock) ({					\
2059	__might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS);	\
2060	__cond_resched_rwlock_write(lock);					\
2061})
2062
2063#ifdef CONFIG_PREEMPT_DYNAMIC
2064
2065extern bool preempt_model_none(void);
2066extern bool preempt_model_voluntary(void);
2067extern bool preempt_model_full(void);
2068
2069#else
2070
2071static inline bool preempt_model_none(void)
2072{
2073	return IS_ENABLED(CONFIG_PREEMPT_NONE);
2074}
2075static inline bool preempt_model_voluntary(void)
2076{
2077	return IS_ENABLED(CONFIG_PREEMPT_VOLUNTARY);
2078}
2079static inline bool preempt_model_full(void)
2080{
2081	return IS_ENABLED(CONFIG_PREEMPT);
2082}
2083
2084#endif
2085
2086static inline bool preempt_model_rt(void)
2087{
2088	return IS_ENABLED(CONFIG_PREEMPT_RT);
2089}
2090
2091/*
2092 * Does the preemption model allow non-cooperative preemption?
2093 *
2094 * For !CONFIG_PREEMPT_DYNAMIC kernels this is an exact match with
2095 * CONFIG_PREEMPTION; for CONFIG_PREEMPT_DYNAMIC this doesn't work as the
2096 * kernel is *built* with CONFIG_PREEMPTION=y but may run with e.g. the
2097 * PREEMPT_NONE model.
2098 */
2099static inline bool preempt_model_preemptible(void)
2100{
2101	return preempt_model_full() || preempt_model_rt();
2102}
2103
2104static __always_inline bool need_resched(void)
2105{
2106	return unlikely(tif_need_resched());
2107}
2108
2109/*
2110 * Wrappers for p->thread_info->cpu access. No-op on UP.
2111 */
2112#ifdef CONFIG_SMP
2113
2114static inline unsigned int task_cpu(const struct task_struct *p)
2115{
2116	return READ_ONCE(task_thread_info(p)->cpu);
2117}
2118
2119extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2120
2121#else
2122
2123static inline unsigned int task_cpu(const struct task_struct *p)
2124{
2125	return 0;
2126}
2127
2128static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2129{
2130}
2131
2132#endif /* CONFIG_SMP */
2133
2134extern bool sched_task_on_rq(struct task_struct *p);
2135extern unsigned long get_wchan(struct task_struct *p);
2136extern struct task_struct *cpu_curr_snapshot(int cpu);
2137
2138#include <linux/spinlock.h>
2139
2140/*
2141 * In order to reduce various lock holder preemption latencies provide an
2142 * interface to see if a vCPU is currently running or not.
2143 *
2144 * This allows us to terminate optimistic spin loops and block, analogous to
2145 * the native optimistic spin heuristic of testing if the lock owner task is
2146 * running or not.
2147 */
2148#ifndef vcpu_is_preempted
2149static inline bool vcpu_is_preempted(int cpu)
2150{
2151	return false;
2152}
2153#endif
2154
2155extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2156extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2157
2158#ifndef TASK_SIZE_OF
2159#define TASK_SIZE_OF(tsk)	TASK_SIZE
2160#endif
2161
2162#ifdef CONFIG_SMP
2163static inline bool owner_on_cpu(struct task_struct *owner)
2164{
2165	/*
2166	 * As lock holder preemption issue, we both skip spinning if
2167	 * task is not on cpu or its cpu is preempted
2168	 */
2169	return READ_ONCE(owner->on_cpu) && !vcpu_is_preempted(task_cpu(owner));
2170}
2171
2172/* Returns effective CPU energy utilization, as seen by the scheduler */
2173unsigned long sched_cpu_util(int cpu);
2174#endif /* CONFIG_SMP */
2175
2176#ifdef CONFIG_SCHED_CORE
2177extern void sched_core_free(struct task_struct *tsk);
2178extern void sched_core_fork(struct task_struct *p);
2179extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type,
2180				unsigned long uaddr);
2181extern int sched_core_idle_cpu(int cpu);
2182#else
2183static inline void sched_core_free(struct task_struct *tsk) { }
2184static inline void sched_core_fork(struct task_struct *p) { }
2185static inline int sched_core_idle_cpu(int cpu) { return idle_cpu(cpu); }
2186#endif
2187
2188extern void sched_set_stop_task(int cpu, struct task_struct *stop);
2189
2190#endif
2191