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1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_SCHED_H
3 #define _LINUX_SCHED_H
4 
5 /*
6  * Define 'struct task_struct' and provide the main scheduler
7  * APIs (schedule(), wakeup variants, etc.)
8  */
9 
10 #include <uapi/linux/sched.h>
11 
12 #include <asm/current.h>
13 
14 #include <linux/pid.h>
15 #include <linux/sem.h>
16 #include <linux/shm.h>
17 #include <linux/mutex.h>
18 #include <linux/plist.h>
19 #include <linux/hrtimer.h>
20 #include <linux/irqflags.h>
21 #include <linux/seccomp.h>
22 #include <linux/nodemask.h>
23 #include <linux/rcupdate.h>
24 #include <linux/refcount.h>
25 #include <linux/resource.h>
26 #include <linux/latencytop.h>
27 #include <linux/sched/prio.h>
28 #include <linux/sched/types.h>
29 #include <linux/signal_types.h>
30 #include <linux/syscall_user_dispatch.h>
31 #include <linux/mm_types_task.h>
32 #include <linux/task_io_accounting.h>
33 #include <linux/posix-timers.h>
34 #include <linux/rseq.h>
35 #include <linux/seqlock.h>
36 #include <linux/kcsan.h>
37 #include <linux/android_vendor.h>
38 #include <asm/kmap_size.h>
39 #include <linux/android_kabi.h>
40 
41 /* task_struct member predeclarations (sorted alphabetically): */
42 struct audit_context;
43 struct backing_dev_info;
44 struct bio_list;
45 struct blk_plug;
46 struct bpf_local_storage;
47 struct bpf_run_ctx;
48 struct capture_control;
49 struct cfs_rq;
50 struct fs_struct;
51 struct futex_pi_state;
52 struct io_context;
53 struct io_uring_task;
54 struct mempolicy;
55 struct nameidata;
56 struct nsproxy;
57 struct perf_event_context;
58 struct pid_namespace;
59 struct pipe_inode_info;
60 struct rcu_node;
61 struct reclaim_state;
62 struct robust_list_head;
63 struct root_domain;
64 struct rq;
65 struct sched_attr;
66 struct sched_param;
67 struct seq_file;
68 struct sighand_struct;
69 struct signal_struct;
70 struct task_delay_info;
71 struct task_group;
72 
73 /*
74  * Task state bitmask. NOTE! These bits are also
75  * encoded in fs/proc/array.c: get_task_state().
76  *
77  * We have two separate sets of flags: task->state
78  * is about runnability, while task->exit_state are
79  * about the task exiting. Confusing, but this way
80  * modifying one set can't modify the other one by
81  * mistake.
82  */
83 
84 /* Used in tsk->state: */
85 #define TASK_RUNNING			0x0000
86 #define TASK_INTERRUPTIBLE		0x0001
87 #define TASK_UNINTERRUPTIBLE		0x0002
88 #define __TASK_STOPPED			0x0004
89 #define __TASK_TRACED			0x0008
90 /* Used in tsk->exit_state: */
91 #define EXIT_DEAD			0x0010
92 #define EXIT_ZOMBIE			0x0020
93 #define EXIT_TRACE			(EXIT_ZOMBIE | EXIT_DEAD)
94 /* Used in tsk->state again: */
95 #define TASK_PARKED			0x0040
96 #define TASK_DEAD			0x0080
97 #define TASK_WAKEKILL			0x0100
98 #define TASK_WAKING			0x0200
99 #define TASK_NOLOAD			0x0400
100 #define TASK_NEW			0x0800
101 /* RT specific auxilliary flag to mark RT lock waiters */
102 #define TASK_RTLOCK_WAIT		0x1000
103 #define TASK_STATE_MAX			0x2000
104 
105 /* Convenience macros for the sake of set_current_state: */
106 #define TASK_KILLABLE			(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
107 #define TASK_STOPPED			(TASK_WAKEKILL | __TASK_STOPPED)
108 #define TASK_TRACED			(TASK_WAKEKILL | __TASK_TRACED)
109 
110 #define TASK_IDLE			(TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
111 
112 /* Convenience macros for the sake of wake_up(): */
113 #define TASK_NORMAL			(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
114 
115 /* get_task_state(): */
116 #define TASK_REPORT			(TASK_RUNNING | TASK_INTERRUPTIBLE | \
117 					 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
118 					 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \
119 					 TASK_PARKED)
120 
121 #define task_is_running(task)		(READ_ONCE((task)->__state) == TASK_RUNNING)
122 
123 #define task_is_traced(task)		((READ_ONCE(task->__state) & __TASK_TRACED) != 0)
124 
125 #define task_is_stopped(task)		((READ_ONCE(task->__state) & __TASK_STOPPED) != 0)
126 
127 #define task_is_stopped_or_traced(task)	((READ_ONCE(task->__state) & (__TASK_STOPPED | __TASK_TRACED)) != 0)
128 
129 /*
130  * Special states are those that do not use the normal wait-loop pattern. See
131  * the comment with set_special_state().
132  */
133 #define is_special_task_state(state)				\
134 	((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | TASK_DEAD))
135 
136 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
137 # define debug_normal_state_change(state_value)				\
138 	do {								\
139 		WARN_ON_ONCE(is_special_task_state(state_value));	\
140 		current->task_state_change = _THIS_IP_;			\
141 	} while (0)
142 
143 # define debug_special_state_change(state_value)			\
144 	do {								\
145 		WARN_ON_ONCE(!is_special_task_state(state_value));	\
146 		current->task_state_change = _THIS_IP_;			\
147 	} while (0)
148 
149 # define debug_rtlock_wait_set_state()					\
150 	do {								 \
151 		current->saved_state_change = current->task_state_change;\
152 		current->task_state_change = _THIS_IP_;			 \
153 	} while (0)
154 
155 # define debug_rtlock_wait_restore_state()				\
156 	do {								 \
157 		current->task_state_change = current->saved_state_change;\
158 	} while (0)
159 
160 #else
161 # define debug_normal_state_change(cond)	do { } while (0)
162 # define debug_special_state_change(cond)	do { } while (0)
163 # define debug_rtlock_wait_set_state()		do { } while (0)
164 # define debug_rtlock_wait_restore_state()	do { } while (0)
165 #endif
166 
167 /*
168  * set_current_state() includes a barrier so that the write of current->state
169  * is correctly serialised wrt the caller's subsequent test of whether to
170  * actually sleep:
171  *
172  *   for (;;) {
173  *	set_current_state(TASK_UNINTERRUPTIBLE);
174  *	if (CONDITION)
175  *	   break;
176  *
177  *	schedule();
178  *   }
179  *   __set_current_state(TASK_RUNNING);
180  *
181  * If the caller does not need such serialisation (because, for instance, the
182  * CONDITION test and condition change and wakeup are under the same lock) then
183  * use __set_current_state().
184  *
185  * The above is typically ordered against the wakeup, which does:
186  *
187  *   CONDITION = 1;
188  *   wake_up_state(p, TASK_UNINTERRUPTIBLE);
189  *
190  * where wake_up_state()/try_to_wake_up() executes a full memory barrier before
191  * accessing p->state.
192  *
193  * Wakeup will do: if (@state & p->state) p->state = TASK_RUNNING, that is,
194  * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a
195  * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING).
196  *
197  * However, with slightly different timing the wakeup TASK_RUNNING store can
198  * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not
199  * a problem either because that will result in one extra go around the loop
200  * and our @cond test will save the day.
201  *
202  * Also see the comments of try_to_wake_up().
203  */
204 #define __set_current_state(state_value)				\
205 	do {								\
206 		debug_normal_state_change((state_value));		\
207 		WRITE_ONCE(current->__state, (state_value));		\
208 	} while (0)
209 
210 #define set_current_state(state_value)					\
211 	do {								\
212 		debug_normal_state_change((state_value));		\
213 		smp_store_mb(current->__state, (state_value));		\
214 	} while (0)
215 
216 /*
217  * set_special_state() should be used for those states when the blocking task
218  * can not use the regular condition based wait-loop. In that case we must
219  * serialize against wakeups such that any possible in-flight TASK_RUNNING
220  * stores will not collide with our state change.
221  */
222 #define set_special_state(state_value)					\
223 	do {								\
224 		unsigned long flags; /* may shadow */			\
225 									\
226 		raw_spin_lock_irqsave(&current->pi_lock, flags);	\
227 		debug_special_state_change((state_value));		\
228 		WRITE_ONCE(current->__state, (state_value));		\
229 		raw_spin_unlock_irqrestore(&current->pi_lock, flags);	\
230 	} while (0)
231 
232 /*
233  * PREEMPT_RT specific variants for "sleeping" spin/rwlocks
234  *
235  * RT's spin/rwlock substitutions are state preserving. The state of the
236  * task when blocking on the lock is saved in task_struct::saved_state and
237  * restored after the lock has been acquired.  These operations are
238  * serialized by task_struct::pi_lock against try_to_wake_up(). Any non RT
239  * lock related wakeups while the task is blocked on the lock are
240  * redirected to operate on task_struct::saved_state to ensure that these
241  * are not dropped. On restore task_struct::saved_state is set to
242  * TASK_RUNNING so any wakeup attempt redirected to saved_state will fail.
243  *
244  * The lock operation looks like this:
245  *
246  *	current_save_and_set_rtlock_wait_state();
247  *	for (;;) {
248  *		if (try_lock())
249  *			break;
250  *		raw_spin_unlock_irq(&lock->wait_lock);
251  *		schedule_rtlock();
252  *		raw_spin_lock_irq(&lock->wait_lock);
253  *		set_current_state(TASK_RTLOCK_WAIT);
254  *	}
255  *	current_restore_rtlock_saved_state();
256  */
257 #define current_save_and_set_rtlock_wait_state()			\
258 	do {								\
259 		lockdep_assert_irqs_disabled();				\
260 		raw_spin_lock(&current->pi_lock);			\
261 		current->saved_state = current->__state;		\
262 		debug_rtlock_wait_set_state();				\
263 		WRITE_ONCE(current->__state, TASK_RTLOCK_WAIT);		\
264 		raw_spin_unlock(&current->pi_lock);			\
265 	} while (0);
266 
267 #define current_restore_rtlock_saved_state()				\
268 	do {								\
269 		lockdep_assert_irqs_disabled();				\
270 		raw_spin_lock(&current->pi_lock);			\
271 		debug_rtlock_wait_restore_state();			\
272 		WRITE_ONCE(current->__state, current->saved_state);	\
273 		current->saved_state = TASK_RUNNING;			\
274 		raw_spin_unlock(&current->pi_lock);			\
275 	} while (0);
276 
277 #define get_current_state()	READ_ONCE(current->__state)
278 
279 /* Task command name length: */
280 #define TASK_COMM_LEN			16
281 
282 extern void scheduler_tick(void);
283 
284 #define	MAX_SCHEDULE_TIMEOUT		LONG_MAX
285 
286 extern long schedule_timeout(long timeout);
287 extern long schedule_timeout_interruptible(long timeout);
288 extern long schedule_timeout_killable(long timeout);
289 extern long schedule_timeout_uninterruptible(long timeout);
290 extern long schedule_timeout_idle(long timeout);
291 asmlinkage void schedule(void);
292 extern void schedule_preempt_disabled(void);
293 asmlinkage void preempt_schedule_irq(void);
294 #ifdef CONFIG_PREEMPT_RT
295  extern void schedule_rtlock(void);
296 #endif
297 
298 extern int __must_check io_schedule_prepare(void);
299 extern void io_schedule_finish(int token);
300 extern long io_schedule_timeout(long timeout);
301 extern void io_schedule(void);
302 extern struct task_struct *pick_migrate_task(struct rq *rq);
303 extern int select_fallback_rq(int cpu, struct task_struct *p);
304 
305 /**
306  * struct prev_cputime - snapshot of system and user cputime
307  * @utime: time spent in user mode
308  * @stime: time spent in system mode
309  * @lock: protects the above two fields
310  *
311  * Stores previous user/system time values such that we can guarantee
312  * monotonicity.
313  */
314 struct prev_cputime {
315 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
316 	u64				utime;
317 	u64				stime;
318 	raw_spinlock_t			lock;
319 #endif
320 };
321 
322 enum vtime_state {
323 	/* Task is sleeping or running in a CPU with VTIME inactive: */
324 	VTIME_INACTIVE = 0,
325 	/* Task is idle */
326 	VTIME_IDLE,
327 	/* Task runs in kernelspace in a CPU with VTIME active: */
328 	VTIME_SYS,
329 	/* Task runs in userspace in a CPU with VTIME active: */
330 	VTIME_USER,
331 	/* Task runs as guests in a CPU with VTIME active: */
332 	VTIME_GUEST,
333 };
334 
335 struct vtime {
336 	seqcount_t		seqcount;
337 	unsigned long long	starttime;
338 	enum vtime_state	state;
339 	unsigned int		cpu;
340 	u64			utime;
341 	u64			stime;
342 	u64			gtime;
343 };
344 
345 /*
346  * Utilization clamp constraints.
347  * @UCLAMP_MIN:	Minimum utilization
348  * @UCLAMP_MAX:	Maximum utilization
349  * @UCLAMP_CNT:	Utilization clamp constraints count
350  */
351 enum uclamp_id {
352 	UCLAMP_MIN = 0,
353 	UCLAMP_MAX,
354 	UCLAMP_CNT
355 };
356 
357 #ifdef CONFIG_SMP
358 extern struct root_domain def_root_domain;
359 extern struct mutex sched_domains_mutex;
360 #endif
361 
362 struct sched_info {
363 #ifdef CONFIG_SCHED_INFO
364 	/* Cumulative counters: */
365 
366 	/* # of times we have run on this CPU: */
367 	unsigned long			pcount;
368 
369 	/* Time spent waiting on a runqueue: */
370 	unsigned long long		run_delay;
371 
372 	/* Timestamps: */
373 
374 	/* When did we last run on a CPU? */
375 	unsigned long long		last_arrival;
376 
377 	/* When were we last queued to run? */
378 	unsigned long long		last_queued;
379 
380 #endif /* CONFIG_SCHED_INFO */
381 };
382 
383 /*
384  * Integer metrics need fixed point arithmetic, e.g., sched/fair
385  * has a few: load, load_avg, util_avg, freq, and capacity.
386  *
387  * We define a basic fixed point arithmetic range, and then formalize
388  * all these metrics based on that basic range.
389  */
390 # define SCHED_FIXEDPOINT_SHIFT		10
391 # define SCHED_FIXEDPOINT_SCALE		(1L << SCHED_FIXEDPOINT_SHIFT)
392 
393 /* Increase resolution of cpu_capacity calculations */
394 # define SCHED_CAPACITY_SHIFT		SCHED_FIXEDPOINT_SHIFT
395 # define SCHED_CAPACITY_SCALE		(1L << SCHED_CAPACITY_SHIFT)
396 
397 struct load_weight {
398 	unsigned long			weight;
399 	u32				inv_weight;
400 };
401 
402 /**
403  * struct util_est - Estimation utilization of FAIR tasks
404  * @enqueued: instantaneous estimated utilization of a task/cpu
405  * @ewma:     the Exponential Weighted Moving Average (EWMA)
406  *            utilization of a task
407  *
408  * Support data structure to track an Exponential Weighted Moving Average
409  * (EWMA) of a FAIR task's utilization. New samples are added to the moving
410  * average each time a task completes an activation. Sample's weight is chosen
411  * so that the EWMA will be relatively insensitive to transient changes to the
412  * task's workload.
413  *
414  * The enqueued attribute has a slightly different meaning for tasks and cpus:
415  * - task:   the task's util_avg at last task dequeue time
416  * - cfs_rq: the sum of util_est.enqueued for each RUNNABLE task on that CPU
417  * Thus, the util_est.enqueued of a task represents the contribution on the
418  * estimated utilization of the CPU where that task is currently enqueued.
419  *
420  * Only for tasks we track a moving average of the past instantaneous
421  * estimated utilization. This allows to absorb sporadic drops in utilization
422  * of an otherwise almost periodic task.
423  *
424  * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg
425  * updates. When a task is dequeued, its util_est should not be updated if its
426  * util_avg has not been updated in the meantime.
427  * This information is mapped into the MSB bit of util_est.enqueued at dequeue
428  * time. Since max value of util_est.enqueued for a task is 1024 (PELT util_avg
429  * for a task) it is safe to use MSB.
430  */
431 struct util_est {
432 	unsigned int			enqueued;
433 	unsigned int			ewma;
434 #define UTIL_EST_WEIGHT_SHIFT		2
435 #define UTIL_AVG_UNCHANGED		0x80000000
436 } __attribute__((__aligned__(sizeof(u64))));
437 
438 /*
439  * The load/runnable/util_avg accumulates an infinite geometric series
440  * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c).
441  *
442  * [load_avg definition]
443  *
444  *   load_avg = runnable% * scale_load_down(load)
445  *
446  * [runnable_avg definition]
447  *
448  *   runnable_avg = runnable% * SCHED_CAPACITY_SCALE
449  *
450  * [util_avg definition]
451  *
452  *   util_avg = running% * SCHED_CAPACITY_SCALE
453  *
454  * where runnable% is the time ratio that a sched_entity is runnable and
455  * running% the time ratio that a sched_entity is running.
456  *
457  * For cfs_rq, they are the aggregated values of all runnable and blocked
458  * sched_entities.
459  *
460  * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU
461  * capacity scaling. The scaling is done through the rq_clock_pelt that is used
462  * for computing those signals (see update_rq_clock_pelt())
463  *
464  * N.B., the above ratios (runnable% and running%) themselves are in the
465  * range of [0, 1]. To do fixed point arithmetics, we therefore scale them
466  * to as large a range as necessary. This is for example reflected by
467  * util_avg's SCHED_CAPACITY_SCALE.
468  *
469  * [Overflow issue]
470  *
471  * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
472  * with the highest load (=88761), always runnable on a single cfs_rq,
473  * and should not overflow as the number already hits PID_MAX_LIMIT.
474  *
475  * For all other cases (including 32-bit kernels), struct load_weight's
476  * weight will overflow first before we do, because:
477  *
478  *    Max(load_avg) <= Max(load.weight)
479  *
480  * Then it is the load_weight's responsibility to consider overflow
481  * issues.
482  */
483 struct sched_avg {
484 	u64				last_update_time;
485 	u64				load_sum;
486 	u64				runnable_sum;
487 	u32				util_sum;
488 	u32				period_contrib;
489 	unsigned long			load_avg;
490 	unsigned long			runnable_avg;
491 	unsigned long			util_avg;
492 	struct util_est			util_est;
493 } ____cacheline_aligned;
494 
495 struct sched_statistics {
496 #ifdef CONFIG_SCHEDSTATS
497 	u64				wait_start;
498 	u64				wait_max;
499 	u64				wait_count;
500 	u64				wait_sum;
501 	u64				iowait_count;
502 	u64				iowait_sum;
503 
504 	u64				sleep_start;
505 	u64				sleep_max;
506 	s64				sum_sleep_runtime;
507 
508 	u64				block_start;
509 	u64				block_max;
510 	u64				exec_max;
511 	u64				slice_max;
512 
513 	u64				nr_migrations_cold;
514 	u64				nr_failed_migrations_affine;
515 	u64				nr_failed_migrations_running;
516 	u64				nr_failed_migrations_hot;
517 	u64				nr_forced_migrations;
518 
519 	u64				nr_wakeups;
520 	u64				nr_wakeups_sync;
521 	u64				nr_wakeups_migrate;
522 	u64				nr_wakeups_local;
523 	u64				nr_wakeups_remote;
524 	u64				nr_wakeups_affine;
525 	u64				nr_wakeups_affine_attempts;
526 	u64				nr_wakeups_passive;
527 	u64				nr_wakeups_idle;
528 #endif
529 };
530 
531 struct sched_entity {
532 	/* For load-balancing: */
533 	struct load_weight		load;
534 	struct rb_node			run_node;
535 	struct list_head		group_node;
536 	unsigned int			on_rq;
537 
538 	u64				exec_start;
539 	u64				sum_exec_runtime;
540 	u64				vruntime;
541 	u64				prev_sum_exec_runtime;
542 
543 	u64				nr_migrations;
544 
545 	struct sched_statistics		statistics;
546 
547 #ifdef CONFIG_FAIR_GROUP_SCHED
548 	int				depth;
549 	struct sched_entity		*parent;
550 	/* rq on which this entity is (to be) queued: */
551 	struct cfs_rq			*cfs_rq;
552 	/* rq "owned" by this entity/group: */
553 	struct cfs_rq			*my_q;
554 	/* cached value of my_q->h_nr_running */
555 	unsigned long			runnable_weight;
556 #endif
557 
558 #ifdef CONFIG_SMP
559 	/*
560 	 * Per entity load average tracking.
561 	 *
562 	 * Put into separate cache line so it does not
563 	 * collide with read-mostly values above.
564 	 */
565 	struct sched_avg		avg;
566 #endif
567 
568 	ANDROID_KABI_RESERVE(1);
569 	ANDROID_KABI_RESERVE(2);
570 	ANDROID_KABI_RESERVE(3);
571 	ANDROID_KABI_RESERVE(4);
572 };
573 
574 struct sched_rt_entity {
575 	struct list_head		run_list;
576 	unsigned long			timeout;
577 	unsigned long			watchdog_stamp;
578 	unsigned int			time_slice;
579 	unsigned short			on_rq;
580 	unsigned short			on_list;
581 
582 	struct sched_rt_entity		*back;
583 #ifdef CONFIG_RT_GROUP_SCHED
584 	struct sched_rt_entity		*parent;
585 	/* rq on which this entity is (to be) queued: */
586 	struct rt_rq			*rt_rq;
587 	/* rq "owned" by this entity/group: */
588 	struct rt_rq			*my_q;
589 #endif
590 
591 	ANDROID_KABI_RESERVE(1);
592 	ANDROID_KABI_RESERVE(2);
593 	ANDROID_KABI_RESERVE(3);
594 	ANDROID_KABI_RESERVE(4);
595 } __randomize_layout;
596 
597 struct sched_dl_entity {
598 	struct rb_node			rb_node;
599 
600 	/*
601 	 * Original scheduling parameters. Copied here from sched_attr
602 	 * during sched_setattr(), they will remain the same until
603 	 * the next sched_setattr().
604 	 */
605 	u64				dl_runtime;	/* Maximum runtime for each instance	*/
606 	u64				dl_deadline;	/* Relative deadline of each instance	*/
607 	u64				dl_period;	/* Separation of two instances (period) */
608 	u64				dl_bw;		/* dl_runtime / dl_period		*/
609 	u64				dl_density;	/* dl_runtime / dl_deadline		*/
610 
611 	/*
612 	 * Actual scheduling parameters. Initialized with the values above,
613 	 * they are continuously updated during task execution. Note that
614 	 * the remaining runtime could be < 0 in case we are in overrun.
615 	 */
616 	s64				runtime;	/* Remaining runtime for this instance	*/
617 	u64				deadline;	/* Absolute deadline for this instance	*/
618 	unsigned int			flags;		/* Specifying the scheduler behaviour	*/
619 
620 	/*
621 	 * Some bool flags:
622 	 *
623 	 * @dl_throttled tells if we exhausted the runtime. If so, the
624 	 * task has to wait for a replenishment to be performed at the
625 	 * next firing of dl_timer.
626 	 *
627 	 * @dl_boosted tells if we are boosted due to DI. If so we are
628 	 * outside bandwidth enforcement mechanism (but only until we
629 	 * exit the critical section);
630 	 *
631 	 * @dl_yielded tells if task gave up the CPU before consuming
632 	 * all its available runtime during the last job.
633 	 *
634 	 * @dl_non_contending tells if the task is inactive while still
635 	 * contributing to the active utilization. In other words, it
636 	 * indicates if the inactive timer has been armed and its handler
637 	 * has not been executed yet. This flag is useful to avoid race
638 	 * conditions between the inactive timer handler and the wakeup
639 	 * code.
640 	 *
641 	 * @dl_overrun tells if the task asked to be informed about runtime
642 	 * overruns.
643 	 */
644 	unsigned int			dl_throttled      : 1;
645 	unsigned int			dl_yielded        : 1;
646 	unsigned int			dl_non_contending : 1;
647 	unsigned int			dl_overrun	  : 1;
648 
649 	/*
650 	 * Bandwidth enforcement timer. Each -deadline task has its
651 	 * own bandwidth to be enforced, thus we need one timer per task.
652 	 */
653 	struct hrtimer			dl_timer;
654 
655 	/*
656 	 * Inactive timer, responsible for decreasing the active utilization
657 	 * at the "0-lag time". When a -deadline task blocks, it contributes
658 	 * to GRUB's active utilization until the "0-lag time", hence a
659 	 * timer is needed to decrease the active utilization at the correct
660 	 * time.
661 	 */
662 	struct hrtimer inactive_timer;
663 
664 #ifdef CONFIG_RT_MUTEXES
665 	/*
666 	 * Priority Inheritance. When a DEADLINE scheduling entity is boosted
667 	 * pi_se points to the donor, otherwise points to the dl_se it belongs
668 	 * to (the original one/itself).
669 	 */
670 	struct sched_dl_entity *pi_se;
671 #endif
672 };
673 
674 #ifdef CONFIG_UCLAMP_TASK
675 /* Number of utilization clamp buckets (shorter alias) */
676 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT
677 
678 /*
679  * Utilization clamp for a scheduling entity
680  * @value:		clamp value "assigned" to a se
681  * @bucket_id:		bucket index corresponding to the "assigned" value
682  * @active:		the se is currently refcounted in a rq's bucket
683  * @user_defined:	the requested clamp value comes from user-space
684  *
685  * The bucket_id is the index of the clamp bucket matching the clamp value
686  * which is pre-computed and stored to avoid expensive integer divisions from
687  * the fast path.
688  *
689  * The active bit is set whenever a task has got an "effective" value assigned,
690  * which can be different from the clamp value "requested" from user-space.
691  * This allows to know a task is refcounted in the rq's bucket corresponding
692  * to the "effective" bucket_id.
693  *
694  * The user_defined bit is set whenever a task has got a task-specific clamp
695  * value requested from userspace, i.e. the system defaults apply to this task
696  * just as a restriction. This allows to relax default clamps when a less
697  * restrictive task-specific value has been requested, thus allowing to
698  * implement a "nice" semantic. For example, a task running with a 20%
699  * default boost can still drop its own boosting to 0%.
700  */
701 struct uclamp_se {
702 	unsigned int value		: bits_per(SCHED_CAPACITY_SCALE);
703 	unsigned int bucket_id		: bits_per(UCLAMP_BUCKETS);
704 	unsigned int active		: 1;
705 	unsigned int user_defined	: 1;
706 };
707 #endif /* CONFIG_UCLAMP_TASK */
708 
709 union rcu_special {
710 	struct {
711 		u8			blocked;
712 		u8			need_qs;
713 		u8			exp_hint; /* Hint for performance. */
714 		u8			need_mb; /* Readers need smp_mb(). */
715 	} b; /* Bits. */
716 	u32 s; /* Set of bits. */
717 };
718 
719 enum perf_event_task_context {
720 	perf_invalid_context = -1,
721 	perf_hw_context = 0,
722 	perf_sw_context,
723 	perf_nr_task_contexts,
724 };
725 
726 struct wake_q_node {
727 	struct wake_q_node *next;
728 };
729 
730 struct kmap_ctrl {
731 #ifdef CONFIG_KMAP_LOCAL
732 	int				idx;
733 	pte_t				pteval[KM_MAX_IDX];
734 #endif
735 };
736 
737 struct task_struct {
738 #ifdef CONFIG_THREAD_INFO_IN_TASK
739 	/*
740 	 * For reasons of header soup (see current_thread_info()), this
741 	 * must be the first element of task_struct.
742 	 */
743 	struct thread_info		thread_info;
744 #endif
745 	unsigned int			__state;
746 
747 #ifdef CONFIG_PREEMPT_RT
748 	/* saved state for "spinlock sleepers" */
749 	unsigned int			saved_state;
750 #endif
751 
752 	/*
753 	 * This begins the randomizable portion of task_struct. Only
754 	 * scheduling-critical items should be added above here.
755 	 */
756 	randomized_struct_fields_start
757 
758 	void				*stack;
759 	refcount_t			usage;
760 	/* Per task flags (PF_*), defined further below: */
761 	unsigned int			flags;
762 	unsigned int			ptrace;
763 
764 #ifdef CONFIG_SMP
765 	int				on_cpu;
766 	struct __call_single_node	wake_entry;
767 #ifdef CONFIG_THREAD_INFO_IN_TASK
768 	/* Current CPU: */
769 	unsigned int			cpu;
770 #endif
771 	unsigned int			wakee_flips;
772 	unsigned long			wakee_flip_decay_ts;
773 	struct task_struct		*last_wakee;
774 
775 	/*
776 	 * recent_used_cpu is initially set as the last CPU used by a task
777 	 * that wakes affine another task. Waker/wakee relationships can
778 	 * push tasks around a CPU where each wakeup moves to the next one.
779 	 * Tracking a recently used CPU allows a quick search for a recently
780 	 * used CPU that may be idle.
781 	 */
782 	int				recent_used_cpu;
783 	int				wake_cpu;
784 #endif
785 	int				on_rq;
786 
787 	int				prio;
788 	int				static_prio;
789 	int				normal_prio;
790 	unsigned int			rt_priority;
791 
792 	const struct sched_class	*sched_class;
793 	struct sched_entity		se;
794 	struct sched_rt_entity		rt;
795 	struct sched_dl_entity		dl;
796 
797 #ifdef CONFIG_SCHED_CORE
798 	struct rb_node			core_node;
799 	unsigned long			core_cookie;
800 	unsigned int			core_occupation;
801 #endif
802 
803 #ifdef CONFIG_CGROUP_SCHED
804 	struct task_group		*sched_task_group;
805 #endif
806 
807 #ifdef CONFIG_UCLAMP_TASK
808 	/*
809 	 * Clamp values requested for a scheduling entity.
810 	 * Must be updated with task_rq_lock() held.
811 	 */
812 	struct uclamp_se		uclamp_req[UCLAMP_CNT];
813 	/*
814 	 * Effective clamp values used for a scheduling entity.
815 	 * Must be updated with task_rq_lock() held.
816 	 */
817 	struct uclamp_se		uclamp[UCLAMP_CNT];
818 #endif
819 
820 #ifdef CONFIG_PREEMPT_NOTIFIERS
821 	/* List of struct preempt_notifier: */
822 	struct hlist_head		preempt_notifiers;
823 #endif
824 
825 #ifdef CONFIG_BLK_DEV_IO_TRACE
826 	unsigned int			btrace_seq;
827 #endif
828 
829 	unsigned int			policy;
830 	int				nr_cpus_allowed;
831 	const cpumask_t			*cpus_ptr;
832 	cpumask_t			*user_cpus_ptr;
833 	cpumask_t			cpus_mask;
834 	void				*migration_pending;
835 #ifdef CONFIG_SMP
836 	unsigned short			migration_disabled;
837 #endif
838 	unsigned short			migration_flags;
839 
840 #ifdef CONFIG_PREEMPT_RCU
841 	int				rcu_read_lock_nesting;
842 	union rcu_special		rcu_read_unlock_special;
843 	struct list_head		rcu_node_entry;
844 	struct rcu_node			*rcu_blocked_node;
845 #endif /* #ifdef CONFIG_PREEMPT_RCU */
846 
847 #ifdef CONFIG_TASKS_RCU
848 	unsigned long			rcu_tasks_nvcsw;
849 	u8				rcu_tasks_holdout;
850 	u8				rcu_tasks_idx;
851 	int				rcu_tasks_idle_cpu;
852 	struct list_head		rcu_tasks_holdout_list;
853 #endif /* #ifdef CONFIG_TASKS_RCU */
854 
855 #ifdef CONFIG_TASKS_TRACE_RCU
856 	int				trc_reader_nesting;
857 	int				trc_ipi_to_cpu;
858 	union rcu_special		trc_reader_special;
859 	bool				trc_reader_checked;
860 	struct list_head		trc_holdout_list;
861 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */
862 
863 	struct sched_info		sched_info;
864 
865 	struct list_head		tasks;
866 #ifdef CONFIG_SMP
867 	struct plist_node		pushable_tasks;
868 	struct rb_node			pushable_dl_tasks;
869 #endif
870 
871 	struct mm_struct		*mm;
872 	struct mm_struct		*active_mm;
873 
874 	/* Per-thread vma caching: */
875 	struct vmacache			vmacache;
876 
877 #ifdef SPLIT_RSS_COUNTING
878 	struct task_rss_stat		rss_stat;
879 #endif
880 	int				exit_state;
881 	int				exit_code;
882 	int				exit_signal;
883 	/* The signal sent when the parent dies: */
884 	int				pdeath_signal;
885 	/* JOBCTL_*, siglock protected: */
886 	unsigned long			jobctl;
887 
888 	/* Used for emulating ABI behavior of previous Linux versions: */
889 	unsigned int			personality;
890 
891 	/* Scheduler bits, serialized by scheduler locks: */
892 	unsigned			sched_reset_on_fork:1;
893 	unsigned			sched_contributes_to_load:1;
894 	unsigned			sched_migrated:1;
895 #ifdef CONFIG_PSI
896 	unsigned			sched_psi_wake_requeue:1;
897 #endif
898 
899 	/* Force alignment to the next boundary: */
900 	unsigned			:0;
901 
902 	/* Unserialized, strictly 'current' */
903 
904 	/*
905 	 * This field must not be in the scheduler word above due to wakelist
906 	 * queueing no longer being serialized by p->on_cpu. However:
907 	 *
908 	 * p->XXX = X;			ttwu()
909 	 * schedule()			  if (p->on_rq && ..) // false
910 	 *   smp_mb__after_spinlock();	  if (smp_load_acquire(&p->on_cpu) && //true
911 	 *   deactivate_task()		      ttwu_queue_wakelist())
912 	 *     p->on_rq = 0;			p->sched_remote_wakeup = Y;
913 	 *
914 	 * guarantees all stores of 'current' are visible before
915 	 * ->sched_remote_wakeup gets used, so it can be in this word.
916 	 */
917 	unsigned			sched_remote_wakeup:1;
918 
919 	/* Bit to tell LSMs we're in execve(): */
920 	unsigned			in_execve:1;
921 	unsigned			in_iowait:1;
922 #ifndef TIF_RESTORE_SIGMASK
923 	unsigned			restore_sigmask:1;
924 #endif
925 #ifdef CONFIG_MEMCG
926 	unsigned			in_user_fault:1;
927 #endif
928 #ifdef CONFIG_LRU_GEN
929 	/* whether the LRU algorithm may apply to this access */
930 	unsigned			in_lru_fault:1;
931 #endif
932 #ifdef CONFIG_COMPAT_BRK
933 	unsigned			brk_randomized:1;
934 #endif
935 #ifdef CONFIG_CGROUPS
936 	/* disallow userland-initiated cgroup migration */
937 	unsigned			no_cgroup_migration:1;
938 	/* task is frozen/stopped (used by the cgroup freezer) */
939 	unsigned			frozen:1;
940 #endif
941 #ifdef CONFIG_BLK_CGROUP
942 	unsigned			use_memdelay:1;
943 #endif
944 #ifdef CONFIG_PSI
945 	/* Stalled due to lack of memory */
946 	unsigned			in_memstall:1;
947 #endif
948 #ifdef CONFIG_PAGE_OWNER
949 	/* Used by page_owner=on to detect recursion in page tracking. */
950 	unsigned			in_page_owner:1;
951 #endif
952 #ifdef CONFIG_EVENTFD
953 	/* Recursion prevention for eventfd_signal() */
954 	unsigned			in_eventfd_signal:1;
955 #endif
956 
957 	unsigned long			atomic_flags; /* Flags requiring atomic access. */
958 
959 	struct restart_block		restart_block;
960 
961 	pid_t				pid;
962 	pid_t				tgid;
963 
964 #ifdef CONFIG_STACKPROTECTOR
965 	/* Canary value for the -fstack-protector GCC feature: */
966 	unsigned long			stack_canary;
967 #endif
968 	/*
969 	 * Pointers to the (original) parent process, youngest child, younger sibling,
970 	 * older sibling, respectively.  (p->father can be replaced with
971 	 * p->real_parent->pid)
972 	 */
973 
974 	/* Real parent process: */
975 	struct task_struct __rcu	*real_parent;
976 
977 	/* Recipient of SIGCHLD, wait4() reports: */
978 	struct task_struct __rcu	*parent;
979 
980 	/*
981 	 * Children/sibling form the list of natural children:
982 	 */
983 	struct list_head		children;
984 	struct list_head		sibling;
985 	struct task_struct		*group_leader;
986 
987 	/*
988 	 * 'ptraced' is the list of tasks this task is using ptrace() on.
989 	 *
990 	 * This includes both natural children and PTRACE_ATTACH targets.
991 	 * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
992 	 */
993 	struct list_head		ptraced;
994 	struct list_head		ptrace_entry;
995 
996 	/* PID/PID hash table linkage. */
997 	struct pid			*thread_pid;
998 	struct hlist_node		pid_links[PIDTYPE_MAX];
999 	struct list_head		thread_group;
1000 	struct list_head		thread_node;
1001 
1002 	struct completion		*vfork_done;
1003 
1004 	/* CLONE_CHILD_SETTID: */
1005 	int __user			*set_child_tid;
1006 
1007 	/* CLONE_CHILD_CLEARTID: */
1008 	int __user			*clear_child_tid;
1009 
1010 	/* PF_IO_WORKER */
1011 	void				*pf_io_worker;
1012 
1013 	u64				utime;
1014 	u64				stime;
1015 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
1016 	u64				utimescaled;
1017 	u64				stimescaled;
1018 #endif
1019 	u64				gtime;
1020 #ifdef CONFIG_CPU_FREQ_TIMES
1021 	u64				*time_in_state;
1022 	unsigned int			max_state;
1023 #endif
1024 	struct prev_cputime		prev_cputime;
1025 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1026 	struct vtime			vtime;
1027 #endif
1028 
1029 #ifdef CONFIG_NO_HZ_FULL
1030 	atomic_t			tick_dep_mask;
1031 #endif
1032 	/* Context switch counts: */
1033 	unsigned long			nvcsw;
1034 	unsigned long			nivcsw;
1035 
1036 	/* Monotonic time in nsecs: */
1037 	u64				start_time;
1038 
1039 	/* Boot based time in nsecs: */
1040 	u64				start_boottime;
1041 
1042 	/* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
1043 	unsigned long			min_flt;
1044 	unsigned long			maj_flt;
1045 
1046 	/* Empty if CONFIG_POSIX_CPUTIMERS=n */
1047 	struct posix_cputimers		posix_cputimers;
1048 
1049 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK
1050 	struct posix_cputimers_work	posix_cputimers_work;
1051 #endif
1052 
1053 	/* Process credentials: */
1054 
1055 	/* Tracer's credentials at attach: */
1056 	const struct cred __rcu		*ptracer_cred;
1057 
1058 	/* Objective and real subjective task credentials (COW): */
1059 	const struct cred __rcu		*real_cred;
1060 
1061 	/* Effective (overridable) subjective task credentials (COW): */
1062 	const struct cred __rcu		*cred;
1063 
1064 #ifdef CONFIG_KEYS
1065 	/* Cached requested key. */
1066 	struct key			*cached_requested_key;
1067 #endif
1068 
1069 	/*
1070 	 * executable name, excluding path.
1071 	 *
1072 	 * - normally initialized setup_new_exec()
1073 	 * - access it with [gs]et_task_comm()
1074 	 * - lock it with task_lock()
1075 	 */
1076 	char				comm[TASK_COMM_LEN];
1077 
1078 	struct nameidata		*nameidata;
1079 
1080 #ifdef CONFIG_SYSVIPC
1081 	struct sysv_sem			sysvsem;
1082 	struct sysv_shm			sysvshm;
1083 #endif
1084 #ifdef CONFIG_DETECT_HUNG_TASK
1085 	unsigned long			last_switch_count;
1086 	unsigned long			last_switch_time;
1087 #endif
1088 	/* Filesystem information: */
1089 	struct fs_struct		*fs;
1090 
1091 	/* Open file information: */
1092 	struct files_struct		*files;
1093 
1094 #ifdef CONFIG_IO_URING
1095 	struct io_uring_task		*io_uring;
1096 #endif
1097 
1098 	/* Namespaces: */
1099 	struct nsproxy			*nsproxy;
1100 
1101 	/* Signal handlers: */
1102 	struct signal_struct		*signal;
1103 	struct sighand_struct __rcu		*sighand;
1104 	sigset_t			blocked;
1105 	sigset_t			real_blocked;
1106 	/* Restored if set_restore_sigmask() was used: */
1107 	sigset_t			saved_sigmask;
1108 	struct sigpending		pending;
1109 	unsigned long			sas_ss_sp;
1110 	size_t				sas_ss_size;
1111 	unsigned int			sas_ss_flags;
1112 
1113 	struct callback_head		*task_works;
1114 
1115 #ifdef CONFIG_AUDIT
1116 #ifdef CONFIG_AUDITSYSCALL
1117 	struct audit_context		*audit_context;
1118 #endif
1119 	kuid_t				loginuid;
1120 	unsigned int			sessionid;
1121 #endif
1122 	struct seccomp			seccomp;
1123 	struct syscall_user_dispatch	syscall_dispatch;
1124 
1125 	/* Thread group tracking: */
1126 	u64				parent_exec_id;
1127 	u64				self_exec_id;
1128 
1129 	/* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
1130 	spinlock_t			alloc_lock;
1131 
1132 	/* Protection of the PI data structures: */
1133 	raw_spinlock_t			pi_lock;
1134 
1135 	struct wake_q_node		wake_q;
1136 	int				wake_q_count;
1137 
1138 #ifdef CONFIG_RT_MUTEXES
1139 	/* PI waiters blocked on a rt_mutex held by this task: */
1140 	struct rb_root_cached		pi_waiters;
1141 	/* Updated under owner's pi_lock and rq lock */
1142 	struct task_struct		*pi_top_task;
1143 	/* Deadlock detection and priority inheritance handling: */
1144 	struct rt_mutex_waiter		*pi_blocked_on;
1145 #endif
1146 
1147 #ifdef CONFIG_DEBUG_MUTEXES
1148 	/* Mutex deadlock detection: */
1149 	struct mutex_waiter		*blocked_on;
1150 #endif
1151 
1152 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1153 	int				non_block_count;
1154 #endif
1155 
1156 #ifdef CONFIG_TRACE_IRQFLAGS
1157 	struct irqtrace_events		irqtrace;
1158 	unsigned int			hardirq_threaded;
1159 	u64				hardirq_chain_key;
1160 	int				softirqs_enabled;
1161 	int				softirq_context;
1162 	int				irq_config;
1163 #endif
1164 #ifdef CONFIG_PREEMPT_RT
1165 	int				softirq_disable_cnt;
1166 #endif
1167 
1168 #ifdef CONFIG_LOCKDEP
1169 # define MAX_LOCK_DEPTH			48UL
1170 	u64				curr_chain_key;
1171 	int				lockdep_depth;
1172 	unsigned int			lockdep_recursion;
1173 	struct held_lock		held_locks[MAX_LOCK_DEPTH];
1174 #endif
1175 
1176 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP)
1177 	unsigned int			in_ubsan;
1178 #endif
1179 
1180 	/* Journalling filesystem info: */
1181 	void				*journal_info;
1182 
1183 	/* Stacked block device info: */
1184 	struct bio_list			*bio_list;
1185 
1186 #ifdef CONFIG_BLOCK
1187 	/* Stack plugging: */
1188 	struct blk_plug			*plug;
1189 #endif
1190 
1191 	/* VM state: */
1192 	struct reclaim_state		*reclaim_state;
1193 
1194 	struct backing_dev_info		*backing_dev_info;
1195 
1196 	struct io_context		*io_context;
1197 
1198 #ifdef CONFIG_COMPACTION
1199 	struct capture_control		*capture_control;
1200 #endif
1201 	/* Ptrace state: */
1202 	unsigned long			ptrace_message;
1203 	kernel_siginfo_t		*last_siginfo;
1204 
1205 	struct task_io_accounting	ioac;
1206 #ifdef CONFIG_PSI
1207 	/* Pressure stall state */
1208 	unsigned int			psi_flags;
1209 #endif
1210 #ifdef CONFIG_TASK_XACCT
1211 	/* Accumulated RSS usage: */
1212 	u64				acct_rss_mem1;
1213 	/* Accumulated virtual memory usage: */
1214 	u64				acct_vm_mem1;
1215 	/* stime + utime since last update: */
1216 	u64				acct_timexpd;
1217 #endif
1218 #ifdef CONFIG_CPUSETS
1219 	/* Protected by ->alloc_lock: */
1220 	nodemask_t			mems_allowed;
1221 	/* Sequence number to catch updates: */
1222 	seqcount_spinlock_t		mems_allowed_seq;
1223 	int				cpuset_mem_spread_rotor;
1224 	int				cpuset_slab_spread_rotor;
1225 #endif
1226 #ifdef CONFIG_CGROUPS
1227 	/* Control Group info protected by css_set_lock: */
1228 	struct css_set __rcu		*cgroups;
1229 	/* cg_list protected by css_set_lock and tsk->alloc_lock: */
1230 	struct list_head		cg_list;
1231 #endif
1232 #ifdef CONFIG_X86_CPU_RESCTRL
1233 	u32				closid;
1234 	u32				rmid;
1235 #endif
1236 #ifdef CONFIG_FUTEX
1237 	struct robust_list_head __user	*robust_list;
1238 #ifdef CONFIG_COMPAT
1239 	struct compat_robust_list_head __user *compat_robust_list;
1240 #endif
1241 	struct list_head		pi_state_list;
1242 	struct futex_pi_state		*pi_state_cache;
1243 	struct mutex			futex_exit_mutex;
1244 	unsigned int			futex_state;
1245 #endif
1246 #ifdef CONFIG_PERF_EVENTS
1247 	struct perf_event_context	*perf_event_ctxp[perf_nr_task_contexts];
1248 	struct mutex			perf_event_mutex;
1249 	struct list_head		perf_event_list;
1250 #endif
1251 #ifdef CONFIG_DEBUG_PREEMPT
1252 	unsigned long			preempt_disable_ip;
1253 #endif
1254 #ifdef CONFIG_NUMA
1255 	/* Protected by alloc_lock: */
1256 	struct mempolicy		*mempolicy;
1257 	short				il_prev;
1258 	short				pref_node_fork;
1259 #endif
1260 #ifdef CONFIG_NUMA_BALANCING
1261 	int				numa_scan_seq;
1262 	unsigned int			numa_scan_period;
1263 	unsigned int			numa_scan_period_max;
1264 	int				numa_preferred_nid;
1265 	unsigned long			numa_migrate_retry;
1266 	/* Migration stamp: */
1267 	u64				node_stamp;
1268 	u64				last_task_numa_placement;
1269 	u64				last_sum_exec_runtime;
1270 	struct callback_head		numa_work;
1271 
1272 	/*
1273 	 * This pointer is only modified for current in syscall and
1274 	 * pagefault context (and for tasks being destroyed), so it can be read
1275 	 * from any of the following contexts:
1276 	 *  - RCU read-side critical section
1277 	 *  - current->numa_group from everywhere
1278 	 *  - task's runqueue locked, task not running
1279 	 */
1280 	struct numa_group __rcu		*numa_group;
1281 
1282 	/*
1283 	 * numa_faults is an array split into four regions:
1284 	 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1285 	 * in this precise order.
1286 	 *
1287 	 * faults_memory: Exponential decaying average of faults on a per-node
1288 	 * basis. Scheduling placement decisions are made based on these
1289 	 * counts. The values remain static for the duration of a PTE scan.
1290 	 * faults_cpu: Track the nodes the process was running on when a NUMA
1291 	 * hinting fault was incurred.
1292 	 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1293 	 * during the current scan window. When the scan completes, the counts
1294 	 * in faults_memory and faults_cpu decay and these values are copied.
1295 	 */
1296 	unsigned long			*numa_faults;
1297 	unsigned long			total_numa_faults;
1298 
1299 	/*
1300 	 * numa_faults_locality tracks if faults recorded during the last
1301 	 * scan window were remote/local or failed to migrate. The task scan
1302 	 * period is adapted based on the locality of the faults with different
1303 	 * weights depending on whether they were shared or private faults
1304 	 */
1305 	unsigned long			numa_faults_locality[3];
1306 
1307 	unsigned long			numa_pages_migrated;
1308 #endif /* CONFIG_NUMA_BALANCING */
1309 
1310 #ifdef CONFIG_RSEQ
1311 	struct rseq __user *rseq;
1312 	u32 rseq_sig;
1313 	/*
1314 	 * RmW on rseq_event_mask must be performed atomically
1315 	 * with respect to preemption.
1316 	 */
1317 	unsigned long rseq_event_mask;
1318 #endif
1319 
1320 	struct tlbflush_unmap_batch	tlb_ubc;
1321 
1322 	union {
1323 		refcount_t		rcu_users;
1324 		struct rcu_head		rcu;
1325 	};
1326 
1327 	/* Cache last used pipe for splice(): */
1328 	struct pipe_inode_info		*splice_pipe;
1329 
1330 	struct page_frag		task_frag;
1331 
1332 #ifdef CONFIG_TASK_DELAY_ACCT
1333 	struct task_delay_info		*delays;
1334 #endif
1335 
1336 #ifdef CONFIG_FAULT_INJECTION
1337 	int				make_it_fail;
1338 	unsigned int			fail_nth;
1339 #endif
1340 	/*
1341 	 * When (nr_dirtied >= nr_dirtied_pause), it's time to call
1342 	 * balance_dirty_pages() for a dirty throttling pause:
1343 	 */
1344 	int				nr_dirtied;
1345 	int				nr_dirtied_pause;
1346 	/* Start of a write-and-pause period: */
1347 	unsigned long			dirty_paused_when;
1348 
1349 #ifdef CONFIG_LATENCYTOP
1350 	int				latency_record_count;
1351 	struct latency_record		latency_record[LT_SAVECOUNT];
1352 #endif
1353 	/*
1354 	 * Time slack values; these are used to round up poll() and
1355 	 * select() etc timeout values. These are in nanoseconds.
1356 	 */
1357 	u64				timer_slack_ns;
1358 	u64				default_timer_slack_ns;
1359 
1360 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
1361 	unsigned int			kasan_depth;
1362 #endif
1363 
1364 #ifdef CONFIG_KCSAN
1365 	struct kcsan_ctx		kcsan_ctx;
1366 #ifdef CONFIG_TRACE_IRQFLAGS
1367 	struct irqtrace_events		kcsan_save_irqtrace;
1368 #endif
1369 #endif
1370 
1371 	struct kunit			*kunit_test;
1372 
1373 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1374 	/* Index of current stored address in ret_stack: */
1375 	int				curr_ret_stack;
1376 	int				curr_ret_depth;
1377 
1378 	/* Stack of return addresses for return function tracing: */
1379 	struct ftrace_ret_stack		*ret_stack;
1380 
1381 	/* Timestamp for last schedule: */
1382 	unsigned long long		ftrace_timestamp;
1383 
1384 	/*
1385 	 * Number of functions that haven't been traced
1386 	 * because of depth overrun:
1387 	 */
1388 	atomic_t			trace_overrun;
1389 
1390 	/* Pause tracing: */
1391 	atomic_t			tracing_graph_pause;
1392 #endif
1393 
1394 #ifdef CONFIG_TRACING
1395 	/* State flags for use by tracers: */
1396 	unsigned long			trace;
1397 
1398 	/* Bitmask and counter of trace recursion: */
1399 	unsigned long			trace_recursion;
1400 #endif /* CONFIG_TRACING */
1401 
1402 #ifdef CONFIG_KCOV
1403 	/* See kernel/kcov.c for more details. */
1404 
1405 	/* Coverage collection mode enabled for this task (0 if disabled): */
1406 	unsigned int			kcov_mode;
1407 
1408 	/* Size of the kcov_area: */
1409 	unsigned int			kcov_size;
1410 
1411 	/* Buffer for coverage collection: */
1412 	void				*kcov_area;
1413 
1414 	/* KCOV descriptor wired with this task or NULL: */
1415 	struct kcov			*kcov;
1416 
1417 	/* KCOV common handle for remote coverage collection: */
1418 	u64				kcov_handle;
1419 
1420 	/* KCOV sequence number: */
1421 	int				kcov_sequence;
1422 
1423 	/* Collect coverage from softirq context: */
1424 	unsigned int			kcov_softirq;
1425 #endif
1426 
1427 #ifdef CONFIG_MEMCG
1428 	struct mem_cgroup		*memcg_in_oom;
1429 	gfp_t				memcg_oom_gfp_mask;
1430 	int				memcg_oom_order;
1431 
1432 	/* Number of pages to reclaim on returning to userland: */
1433 	unsigned int			memcg_nr_pages_over_high;
1434 
1435 	/* Used by memcontrol for targeted memcg charge: */
1436 	struct mem_cgroup		*active_memcg;
1437 #endif
1438 
1439 #ifdef CONFIG_BLK_CGROUP
1440 	struct request_queue		*throttle_queue;
1441 #endif
1442 
1443 #ifdef CONFIG_UPROBES
1444 	struct uprobe_task		*utask;
1445 #endif
1446 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1447 	unsigned int			sequential_io;
1448 	unsigned int			sequential_io_avg;
1449 #endif
1450 	struct kmap_ctrl		kmap_ctrl;
1451 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1452 	unsigned long			task_state_change;
1453 # ifdef CONFIG_PREEMPT_RT
1454 	unsigned long			saved_state_change;
1455 # endif
1456 #endif
1457 	int				pagefault_disabled;
1458 #ifdef CONFIG_MMU
1459 	struct task_struct		*oom_reaper_list;
1460 	struct timer_list		oom_reaper_timer;
1461 #endif
1462 #ifdef CONFIG_VMAP_STACK
1463 	struct vm_struct		*stack_vm_area;
1464 #endif
1465 #ifdef CONFIG_THREAD_INFO_IN_TASK
1466 	/* A live task holds one reference: */
1467 	refcount_t			stack_refcount;
1468 #endif
1469 #ifdef CONFIG_LIVEPATCH
1470 	int patch_state;
1471 #endif
1472 #ifdef CONFIG_SECURITY
1473 	/* Used by LSM modules for access restriction: */
1474 	void				*security;
1475 #endif
1476 #ifdef CONFIG_BPF_SYSCALL
1477 	/* Used by BPF task local storage */
1478 	struct bpf_local_storage __rcu	*bpf_storage;
1479 	/* Used for BPF run context */
1480 	struct bpf_run_ctx		*bpf_ctx;
1481 #endif
1482 
1483 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK
1484 	unsigned long			lowest_stack;
1485 	unsigned long			prev_lowest_stack;
1486 #endif
1487 
1488 #ifdef CONFIG_X86_MCE
1489 	void __user			*mce_vaddr;
1490 	__u64				mce_kflags;
1491 	u64				mce_addr;
1492 	__u64				mce_ripv : 1,
1493 					mce_whole_page : 1,
1494 					__mce_reserved : 62;
1495 	struct callback_head		mce_kill_me;
1496 	int				mce_count;
1497 #endif
1498 	ANDROID_VENDOR_DATA_ARRAY(1, 64);
1499 	ANDROID_OEM_DATA_ARRAY(1, 6);
1500 
1501 #ifdef CONFIG_KRETPROBES
1502 	struct llist_head               kretprobe_instances;
1503 #endif
1504 
1505 #ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH
1506 	/*
1507 	 * If L1D flush is supported on mm context switch
1508 	 * then we use this callback head to queue kill work
1509 	 * to kill tasks that are not running on SMT disabled
1510 	 * cores
1511 	 */
1512 	struct callback_head		l1d_flush_kill;
1513 #endif
1514 
1515 	ANDROID_KABI_RESERVE(1);
1516 	ANDROID_KABI_RESERVE(2);
1517 	ANDROID_KABI_RESERVE(3);
1518 	ANDROID_KABI_RESERVE(4);
1519 	ANDROID_KABI_RESERVE(5);
1520 	ANDROID_KABI_RESERVE(6);
1521 	ANDROID_KABI_RESERVE(7);
1522 	ANDROID_KABI_RESERVE(8);
1523 
1524 	/*
1525 	 * New fields for task_struct should be added above here, so that
1526 	 * they are included in the randomized portion of task_struct.
1527 	 */
1528 	randomized_struct_fields_end
1529 
1530 	/* CPU-specific state of this task: */
1531 	struct thread_struct		thread;
1532 
1533 	/*
1534 	 * WARNING: on x86, 'thread_struct' contains a variable-sized
1535 	 * structure.  It *MUST* be at the end of 'task_struct'.
1536 	 *
1537 	 * Do not put anything below here!
1538 	 */
1539 };
1540 
task_pid(struct task_struct * task)1541 static inline struct pid *task_pid(struct task_struct *task)
1542 {
1543 	return task->thread_pid;
1544 }
1545 
1546 /*
1547  * the helpers to get the task's different pids as they are seen
1548  * from various namespaces
1549  *
1550  * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1551  * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1552  *                     current.
1553  * task_xid_nr_ns()  : id seen from the ns specified;
1554  *
1555  * see also pid_nr() etc in include/linux/pid.h
1556  */
1557 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, struct pid_namespace *ns);
1558 
task_pid_nr(struct task_struct * tsk)1559 static inline pid_t task_pid_nr(struct task_struct *tsk)
1560 {
1561 	return tsk->pid;
1562 }
1563 
task_pid_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1564 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1565 {
1566 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1567 }
1568 
task_pid_vnr(struct task_struct * tsk)1569 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1570 {
1571 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1572 }
1573 
1574 
task_tgid_nr(struct task_struct * tsk)1575 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1576 {
1577 	return tsk->tgid;
1578 }
1579 
1580 /**
1581  * pid_alive - check that a task structure is not stale
1582  * @p: Task structure to be checked.
1583  *
1584  * Test if a process is not yet dead (at most zombie state)
1585  * If pid_alive fails, then pointers within the task structure
1586  * can be stale and must not be dereferenced.
1587  *
1588  * Return: 1 if the process is alive. 0 otherwise.
1589  */
pid_alive(const struct task_struct * p)1590 static inline int pid_alive(const struct task_struct *p)
1591 {
1592 	return p->thread_pid != NULL;
1593 }
1594 
task_pgrp_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1595 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1596 {
1597 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1598 }
1599 
task_pgrp_vnr(struct task_struct * tsk)1600 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1601 {
1602 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1603 }
1604 
1605 
task_session_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1606 static inline pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1607 {
1608 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1609 }
1610 
task_session_vnr(struct task_struct * tsk)1611 static inline pid_t task_session_vnr(struct task_struct *tsk)
1612 {
1613 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1614 }
1615 
task_tgid_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1616 static inline pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1617 {
1618 	return __task_pid_nr_ns(tsk, PIDTYPE_TGID, ns);
1619 }
1620 
task_tgid_vnr(struct task_struct * tsk)1621 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1622 {
1623 	return __task_pid_nr_ns(tsk, PIDTYPE_TGID, NULL);
1624 }
1625 
task_ppid_nr_ns(const struct task_struct * tsk,struct pid_namespace * ns)1626 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1627 {
1628 	pid_t pid = 0;
1629 
1630 	rcu_read_lock();
1631 	if (pid_alive(tsk))
1632 		pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1633 	rcu_read_unlock();
1634 
1635 	return pid;
1636 }
1637 
task_ppid_nr(const struct task_struct * tsk)1638 static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1639 {
1640 	return task_ppid_nr_ns(tsk, &init_pid_ns);
1641 }
1642 
1643 /* Obsolete, do not use: */
task_pgrp_nr(struct task_struct * tsk)1644 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1645 {
1646 	return task_pgrp_nr_ns(tsk, &init_pid_ns);
1647 }
1648 
1649 #define TASK_REPORT_IDLE	(TASK_REPORT + 1)
1650 #define TASK_REPORT_MAX		(TASK_REPORT_IDLE << 1)
1651 
task_state_index(struct task_struct * tsk)1652 static inline unsigned int task_state_index(struct task_struct *tsk)
1653 {
1654 	unsigned int tsk_state = READ_ONCE(tsk->__state);
1655 	unsigned int state = (tsk_state | tsk->exit_state) & TASK_REPORT;
1656 
1657 	BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);
1658 
1659 	if (tsk_state == TASK_IDLE)
1660 		state = TASK_REPORT_IDLE;
1661 
1662 	/*
1663 	 * We're lying here, but rather than expose a completely new task state
1664 	 * to userspace, we can make this appear as if the task has gone through
1665 	 * a regular rt_mutex_lock() call.
1666 	 */
1667 	if (tsk_state == TASK_RTLOCK_WAIT)
1668 		state = TASK_UNINTERRUPTIBLE;
1669 
1670 	return fls(state);
1671 }
1672 
task_index_to_char(unsigned int state)1673 static inline char task_index_to_char(unsigned int state)
1674 {
1675 	static const char state_char[] = "RSDTtXZPI";
1676 
1677 	BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1);
1678 
1679 	return state_char[state];
1680 }
1681 
task_state_to_char(struct task_struct * tsk)1682 static inline char task_state_to_char(struct task_struct *tsk)
1683 {
1684 	return task_index_to_char(task_state_index(tsk));
1685 }
1686 
1687 /**
1688  * is_global_init - check if a task structure is init. Since init
1689  * is free to have sub-threads we need to check tgid.
1690  * @tsk: Task structure to be checked.
1691  *
1692  * Check if a task structure is the first user space task the kernel created.
1693  *
1694  * Return: 1 if the task structure is init. 0 otherwise.
1695  */
is_global_init(struct task_struct * tsk)1696 static inline int is_global_init(struct task_struct *tsk)
1697 {
1698 	return task_tgid_nr(tsk) == 1;
1699 }
1700 
1701 extern struct pid *cad_pid;
1702 
1703 /*
1704  * Per process flags
1705  */
1706 #define PF_VCPU			0x00000001	/* I'm a virtual CPU */
1707 #define PF_IDLE			0x00000002	/* I am an IDLE thread */
1708 #define PF_EXITING		0x00000004	/* Getting shut down */
1709 #define PF_IO_WORKER		0x00000010	/* Task is an IO worker */
1710 #define PF_WQ_WORKER		0x00000020	/* I'm a workqueue worker */
1711 #define PF_FORKNOEXEC		0x00000040	/* Forked but didn't exec */
1712 #define PF_MCE_PROCESS		0x00000080      /* Process policy on mce errors */
1713 #define PF_SUPERPRIV		0x00000100	/* Used super-user privileges */
1714 #define PF_DUMPCORE		0x00000200	/* Dumped core */
1715 #define PF_SIGNALED		0x00000400	/* Killed by a signal */
1716 #define PF_MEMALLOC		0x00000800	/* Allocating memory */
1717 #define PF_NPROC_EXCEEDED	0x00001000	/* set_user() noticed that RLIMIT_NPROC was exceeded */
1718 #define PF_USED_MATH		0x00002000	/* If unset the fpu must be initialized before use */
1719 #define PF_NOFREEZE		0x00008000	/* This thread should not be frozen */
1720 #define PF_FROZEN		0x00010000	/* Frozen for system suspend */
1721 #define PF_KSWAPD		0x00020000	/* I am kswapd */
1722 #define PF_MEMALLOC_NOFS	0x00040000	/* All allocation requests will inherit GFP_NOFS */
1723 #define PF_MEMALLOC_NOIO	0x00080000	/* All allocation requests will inherit GFP_NOIO */
1724 #define PF_LOCAL_THROTTLE	0x00100000	/* Throttle writes only against the bdi I write to,
1725 						 * I am cleaning dirty pages from some other bdi. */
1726 #define PF_KTHREAD		0x00200000	/* I am a kernel thread */
1727 #define PF_RANDOMIZE		0x00400000	/* Randomize virtual address space */
1728 #define PF_SWAPWRITE		0x00800000	/* Allowed to write to swap */
1729 #define PF_NO_SETAFFINITY	0x04000000	/* Userland is not allowed to meddle with cpus_mask */
1730 #define PF_MCE_EARLY		0x08000000      /* Early kill for mce process policy */
1731 #define PF_MEMALLOC_PIN		0x10000000	/* Allocation context constrained to zones which allow long term pinning. */
1732 #define PF_FREEZER_SKIP		0x40000000	/* Freezer should not count it as freezable */
1733 #define PF_SUSPEND_TASK		0x80000000      /* This thread called freeze_processes() and should not be frozen */
1734 
1735 /*
1736  * Only the _current_ task can read/write to tsk->flags, but other
1737  * tasks can access tsk->flags in readonly mode for example
1738  * with tsk_used_math (like during threaded core dumping).
1739  * There is however an exception to this rule during ptrace
1740  * or during fork: the ptracer task is allowed to write to the
1741  * child->flags of its traced child (same goes for fork, the parent
1742  * can write to the child->flags), because we're guaranteed the
1743  * child is not running and in turn not changing child->flags
1744  * at the same time the parent does it.
1745  */
1746 #define clear_stopped_child_used_math(child)	do { (child)->flags &= ~PF_USED_MATH; } while (0)
1747 #define set_stopped_child_used_math(child)	do { (child)->flags |= PF_USED_MATH; } while (0)
1748 #define clear_used_math()			clear_stopped_child_used_math(current)
1749 #define set_used_math()				set_stopped_child_used_math(current)
1750 
1751 #define conditional_stopped_child_used_math(condition, child) \
1752 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1753 
1754 #define conditional_used_math(condition)	conditional_stopped_child_used_math(condition, current)
1755 
1756 #define copy_to_stopped_child_used_math(child) \
1757 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1758 
1759 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1760 #define tsk_used_math(p)			((p)->flags & PF_USED_MATH)
1761 #define used_math()				tsk_used_math(current)
1762 
is_percpu_thread(void)1763 static __always_inline bool is_percpu_thread(void)
1764 {
1765 #ifdef CONFIG_SMP
1766 	return (current->flags & PF_NO_SETAFFINITY) &&
1767 		(current->nr_cpus_allowed  == 1);
1768 #else
1769 	return true;
1770 #endif
1771 }
1772 
1773 /* Per-process atomic flags. */
1774 #define PFA_NO_NEW_PRIVS		0	/* May not gain new privileges. */
1775 #define PFA_SPREAD_PAGE			1	/* Spread page cache over cpuset */
1776 #define PFA_SPREAD_SLAB			2	/* Spread some slab caches over cpuset */
1777 #define PFA_SPEC_SSB_DISABLE		3	/* Speculative Store Bypass disabled */
1778 #define PFA_SPEC_SSB_FORCE_DISABLE	4	/* Speculative Store Bypass force disabled*/
1779 #define PFA_SPEC_IB_DISABLE		5	/* Indirect branch speculation restricted */
1780 #define PFA_SPEC_IB_FORCE_DISABLE	6	/* Indirect branch speculation permanently restricted */
1781 #define PFA_SPEC_SSB_NOEXEC		7	/* Speculative Store Bypass clear on execve() */
1782 
1783 #define TASK_PFA_TEST(name, func)					\
1784 	static inline bool task_##func(struct task_struct *p)		\
1785 	{ return test_bit(PFA_##name, &p->atomic_flags); }
1786 
1787 #define TASK_PFA_SET(name, func)					\
1788 	static inline void task_set_##func(struct task_struct *p)	\
1789 	{ set_bit(PFA_##name, &p->atomic_flags); }
1790 
1791 #define TASK_PFA_CLEAR(name, func)					\
1792 	static inline void task_clear_##func(struct task_struct *p)	\
1793 	{ clear_bit(PFA_##name, &p->atomic_flags); }
1794 
TASK_PFA_TEST(NO_NEW_PRIVS,no_new_privs)1795 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1796 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1797 
1798 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1799 TASK_PFA_SET(SPREAD_PAGE, spread_page)
1800 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
1801 
1802 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
1803 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
1804 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1805 
1806 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable)
1807 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable)
1808 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable)
1809 
1810 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1811 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1812 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1813 
1814 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1815 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1816 
1817 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable)
1818 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable)
1819 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable)
1820 
1821 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1822 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1823 
1824 static inline void
1825 current_restore_flags(unsigned long orig_flags, unsigned long flags)
1826 {
1827 	current->flags &= ~flags;
1828 	current->flags |= orig_flags & flags;
1829 }
1830 
1831 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
1832 extern int task_can_attach(struct task_struct *p);
1833 extern int dl_bw_alloc(int cpu, u64 dl_bw);
1834 extern void dl_bw_free(int cpu, u64 dl_bw);
1835 
1836 #ifdef CONFIG_RT_SOFTINT_OPTIMIZATION
1837 extern bool cpupri_check_rt(void);
1838 #else
cpupri_check_rt(void)1839 static inline bool cpupri_check_rt(void)
1840 {
1841 	return false;
1842 }
1843 #endif
1844 
1845 #ifdef CONFIG_SMP
1846 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask);
1847 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
1848 extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node);
1849 extern void release_user_cpus_ptr(struct task_struct *p);
1850 extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask);
1851 extern void force_compatible_cpus_allowed_ptr(struct task_struct *p);
1852 extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p);
1853 #else
do_set_cpus_allowed(struct task_struct * p,const struct cpumask * new_mask)1854 static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
1855 {
1856 }
set_cpus_allowed_ptr(struct task_struct * p,const struct cpumask * new_mask)1857 static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
1858 {
1859 	if (!cpumask_test_cpu(0, new_mask))
1860 		return -EINVAL;
1861 	return 0;
1862 }
dup_user_cpus_ptr(struct task_struct * dst,struct task_struct * src,int node)1863 static inline int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node)
1864 {
1865 	if (src->user_cpus_ptr)
1866 		return -EINVAL;
1867 	return 0;
1868 }
release_user_cpus_ptr(struct task_struct * p)1869 static inline void release_user_cpus_ptr(struct task_struct *p)
1870 {
1871 	WARN_ON(p->user_cpus_ptr);
1872 }
1873 
dl_task_check_affinity(struct task_struct * p,const struct cpumask * mask)1874 static inline int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask)
1875 {
1876 	return 0;
1877 }
1878 #endif
1879 
1880 extern int yield_to(struct task_struct *p, bool preempt);
1881 extern void set_user_nice(struct task_struct *p, long nice);
1882 extern int task_prio(const struct task_struct *p);
1883 
1884 /**
1885  * task_nice - return the nice value of a given task.
1886  * @p: the task in question.
1887  *
1888  * Return: The nice value [ -20 ... 0 ... 19 ].
1889  */
task_nice(const struct task_struct * p)1890 static inline int task_nice(const struct task_struct *p)
1891 {
1892 	return PRIO_TO_NICE((p)->static_prio);
1893 }
1894 
1895 extern int can_nice(const struct task_struct *p, const int nice);
1896 extern int task_curr(const struct task_struct *p);
1897 extern int idle_cpu(int cpu);
1898 extern int available_idle_cpu(int cpu);
1899 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
1900 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
1901 extern void sched_set_fifo(struct task_struct *p);
1902 extern void sched_set_fifo_low(struct task_struct *p);
1903 extern void sched_set_normal(struct task_struct *p, int nice);
1904 extern int sched_setattr(struct task_struct *, const struct sched_attr *);
1905 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *);
1906 extern struct task_struct *idle_task(int cpu);
1907 
1908 /**
1909  * is_idle_task - is the specified task an idle task?
1910  * @p: the task in question.
1911  *
1912  * Return: 1 if @p is an idle task. 0 otherwise.
1913  */
is_idle_task(const struct task_struct * p)1914 static __always_inline bool is_idle_task(const struct task_struct *p)
1915 {
1916 	return !!(p->flags & PF_IDLE);
1917 }
1918 
1919 extern struct task_struct *curr_task(int cpu);
1920 extern void ia64_set_curr_task(int cpu, struct task_struct *p);
1921 
1922 void yield(void);
1923 
1924 union thread_union {
1925 #ifndef CONFIG_ARCH_TASK_STRUCT_ON_STACK
1926 	struct task_struct task;
1927 #endif
1928 #ifndef CONFIG_THREAD_INFO_IN_TASK
1929 	struct thread_info thread_info;
1930 #endif
1931 	unsigned long stack[THREAD_SIZE/sizeof(long)];
1932 };
1933 
1934 #ifndef CONFIG_THREAD_INFO_IN_TASK
1935 extern struct thread_info init_thread_info;
1936 #endif
1937 
1938 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];
1939 
1940 #ifdef CONFIG_THREAD_INFO_IN_TASK
task_thread_info(struct task_struct * task)1941 static inline struct thread_info *task_thread_info(struct task_struct *task)
1942 {
1943 	return &task->thread_info;
1944 }
1945 #elif !defined(__HAVE_THREAD_FUNCTIONS)
1946 # define task_thread_info(task)	((struct thread_info *)(task)->stack)
1947 #endif
1948 
1949 /*
1950  * find a task by one of its numerical ids
1951  *
1952  * find_task_by_pid_ns():
1953  *      finds a task by its pid in the specified namespace
1954  * find_task_by_vpid():
1955  *      finds a task by its virtual pid
1956  *
1957  * see also find_vpid() etc in include/linux/pid.h
1958  */
1959 
1960 extern struct task_struct *find_task_by_vpid(pid_t nr);
1961 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns);
1962 
1963 /*
1964  * find a task by its virtual pid and get the task struct
1965  */
1966 extern struct task_struct *find_get_task_by_vpid(pid_t nr);
1967 
1968 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1969 extern int wake_up_process(struct task_struct *tsk);
1970 extern void wake_up_new_task(struct task_struct *tsk);
1971 
1972 #ifdef CONFIG_SMP
1973 extern void kick_process(struct task_struct *tsk);
1974 #else
kick_process(struct task_struct * tsk)1975 static inline void kick_process(struct task_struct *tsk) { }
1976 #endif
1977 
1978 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
1979 
set_task_comm(struct task_struct * tsk,const char * from)1980 static inline void set_task_comm(struct task_struct *tsk, const char *from)
1981 {
1982 	__set_task_comm(tsk, from, false);
1983 }
1984 
1985 extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk);
1986 #define get_task_comm(buf, tsk) ({			\
1987 	BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN);	\
1988 	__get_task_comm(buf, sizeof(buf), tsk);		\
1989 })
1990 
1991 #ifdef CONFIG_SMP
scheduler_ipi(void)1992 static __always_inline void scheduler_ipi(void)
1993 {
1994 	/*
1995 	 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting
1996 	 * TIF_NEED_RESCHED remotely (for the first time) will also send
1997 	 * this IPI.
1998 	 */
1999 	preempt_fold_need_resched();
2000 }
2001 extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state);
2002 #else
scheduler_ipi(void)2003 static inline void scheduler_ipi(void) { }
wait_task_inactive(struct task_struct * p,unsigned int match_state)2004 static inline unsigned long wait_task_inactive(struct task_struct *p, unsigned int match_state)
2005 {
2006 	return 1;
2007 }
2008 #endif
2009 
2010 /*
2011  * Set thread flags in other task's structures.
2012  * See asm/thread_info.h for TIF_xxxx flags available:
2013  */
set_tsk_thread_flag(struct task_struct * tsk,int flag)2014 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2015 {
2016 	set_ti_thread_flag(task_thread_info(tsk), flag);
2017 }
2018 
clear_tsk_thread_flag(struct task_struct * tsk,int flag)2019 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2020 {
2021 	clear_ti_thread_flag(task_thread_info(tsk), flag);
2022 }
2023 
update_tsk_thread_flag(struct task_struct * tsk,int flag,bool value)2024 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag,
2025 					  bool value)
2026 {
2027 	update_ti_thread_flag(task_thread_info(tsk), flag, value);
2028 }
2029 
test_and_set_tsk_thread_flag(struct task_struct * tsk,int flag)2030 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2031 {
2032 	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2033 }
2034 
test_and_clear_tsk_thread_flag(struct task_struct * tsk,int flag)2035 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2036 {
2037 	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2038 }
2039 
test_tsk_thread_flag(struct task_struct * tsk,int flag)2040 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2041 {
2042 	return test_ti_thread_flag(task_thread_info(tsk), flag);
2043 }
2044 
set_tsk_need_resched(struct task_struct * tsk)2045 static inline void set_tsk_need_resched(struct task_struct *tsk)
2046 {
2047 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2048 }
2049 
clear_tsk_need_resched(struct task_struct * tsk)2050 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2051 {
2052 	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2053 }
2054 
test_tsk_need_resched(struct task_struct * tsk)2055 static inline int test_tsk_need_resched(struct task_struct *tsk)
2056 {
2057 	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2058 }
2059 
2060 /*
2061  * cond_resched() and cond_resched_lock(): latency reduction via
2062  * explicit rescheduling in places that are safe. The return
2063  * value indicates whether a reschedule was done in fact.
2064  * cond_resched_lock() will drop the spinlock before scheduling,
2065  */
2066 #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC)
2067 extern int __cond_resched(void);
2068 
2069 #ifdef CONFIG_PREEMPT_DYNAMIC
2070 
2071 DECLARE_STATIC_CALL(cond_resched, __cond_resched);
2072 
_cond_resched(void)2073 static __always_inline int _cond_resched(void)
2074 {
2075 	return static_call_mod(cond_resched)();
2076 }
2077 
2078 #else
2079 
_cond_resched(void)2080 static inline int _cond_resched(void)
2081 {
2082 	return __cond_resched();
2083 }
2084 
2085 #endif /* CONFIG_PREEMPT_DYNAMIC */
2086 
2087 #else
2088 
_cond_resched(void)2089 static inline int _cond_resched(void) { return 0; }
2090 
2091 #endif /* !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) */
2092 
2093 #define cond_resched() ({			\
2094 	___might_sleep(__FILE__, __LINE__, 0);	\
2095 	_cond_resched();			\
2096 })
2097 
2098 extern int __cond_resched_lock(spinlock_t *lock);
2099 extern int __cond_resched_rwlock_read(rwlock_t *lock);
2100 extern int __cond_resched_rwlock_write(rwlock_t *lock);
2101 
2102 #define cond_resched_lock(lock) ({				\
2103 	___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
2104 	__cond_resched_lock(lock);				\
2105 })
2106 
2107 #define cond_resched_rwlock_read(lock) ({			\
2108 	__might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);	\
2109 	__cond_resched_rwlock_read(lock);			\
2110 })
2111 
2112 #define cond_resched_rwlock_write(lock) ({			\
2113 	__might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);	\
2114 	__cond_resched_rwlock_write(lock);			\
2115 })
2116 
cond_resched_rcu(void)2117 static inline void cond_resched_rcu(void)
2118 {
2119 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
2120 	rcu_read_unlock();
2121 	cond_resched();
2122 	rcu_read_lock();
2123 #endif
2124 }
2125 
2126 /*
2127  * Does a critical section need to be broken due to another
2128  * task waiting?: (technically does not depend on CONFIG_PREEMPTION,
2129  * but a general need for low latency)
2130  */
spin_needbreak(spinlock_t * lock)2131 static inline int spin_needbreak(spinlock_t *lock)
2132 {
2133 #ifdef CONFIG_PREEMPTION
2134 	return spin_is_contended(lock);
2135 #else
2136 	return 0;
2137 #endif
2138 }
2139 
2140 /*
2141  * Check if a rwlock is contended.
2142  * Returns non-zero if there is another task waiting on the rwlock.
2143  * Returns zero if the lock is not contended or the system / underlying
2144  * rwlock implementation does not support contention detection.
2145  * Technically does not depend on CONFIG_PREEMPTION, but a general need
2146  * for low latency.
2147  */
rwlock_needbreak(rwlock_t * lock)2148 static inline int rwlock_needbreak(rwlock_t *lock)
2149 {
2150 #ifdef CONFIG_PREEMPTION
2151 	return rwlock_is_contended(lock);
2152 #else
2153 	return 0;
2154 #endif
2155 }
2156 
need_resched(void)2157 static __always_inline bool need_resched(void)
2158 {
2159 	return unlikely(tif_need_resched());
2160 }
2161 
2162 /*
2163  * Wrappers for p->thread_info->cpu access. No-op on UP.
2164  */
2165 #ifdef CONFIG_SMP
2166 
task_cpu(const struct task_struct * p)2167 static inline unsigned int task_cpu(const struct task_struct *p)
2168 {
2169 #ifdef CONFIG_THREAD_INFO_IN_TASK
2170 	return READ_ONCE(p->cpu);
2171 #else
2172 	return READ_ONCE(task_thread_info(p)->cpu);
2173 #endif
2174 }
2175 
2176 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2177 
2178 #else
2179 
task_cpu(const struct task_struct * p)2180 static inline unsigned int task_cpu(const struct task_struct *p)
2181 {
2182 	return 0;
2183 }
2184 
set_task_cpu(struct task_struct * p,unsigned int cpu)2185 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2186 {
2187 }
2188 
2189 #endif /* CONFIG_SMP */
2190 
2191 extern bool sched_task_on_rq(struct task_struct *p);
2192 
2193 /*
2194  * In order to reduce various lock holder preemption latencies provide an
2195  * interface to see if a vCPU is currently running or not.
2196  *
2197  * This allows us to terminate optimistic spin loops and block, analogous to
2198  * the native optimistic spin heuristic of testing if the lock owner task is
2199  * running or not.
2200  */
2201 #ifndef vcpu_is_preempted
vcpu_is_preempted(int cpu)2202 static inline bool vcpu_is_preempted(int cpu)
2203 {
2204 	return false;
2205 }
2206 #endif
2207 
2208 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2209 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2210 
2211 #ifndef TASK_SIZE_OF
2212 #define TASK_SIZE_OF(tsk)	TASK_SIZE
2213 #endif
2214 
2215 #ifdef CONFIG_SMP
2216 /* Returns effective CPU energy utilization, as seen by the scheduler */
2217 unsigned long sched_cpu_util(int cpu, unsigned long max);
2218 #endif /* CONFIG_SMP */
2219 
2220 #ifdef CONFIG_RSEQ
2221 
2222 /*
2223  * Map the event mask on the user-space ABI enum rseq_cs_flags
2224  * for direct mask checks.
2225  */
2226 enum rseq_event_mask_bits {
2227 	RSEQ_EVENT_PREEMPT_BIT	= RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT,
2228 	RSEQ_EVENT_SIGNAL_BIT	= RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT,
2229 	RSEQ_EVENT_MIGRATE_BIT	= RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT,
2230 };
2231 
2232 enum rseq_event_mask {
2233 	RSEQ_EVENT_PREEMPT	= (1U << RSEQ_EVENT_PREEMPT_BIT),
2234 	RSEQ_EVENT_SIGNAL	= (1U << RSEQ_EVENT_SIGNAL_BIT),
2235 	RSEQ_EVENT_MIGRATE	= (1U << RSEQ_EVENT_MIGRATE_BIT),
2236 };
2237 
rseq_set_notify_resume(struct task_struct * t)2238 static inline void rseq_set_notify_resume(struct task_struct *t)
2239 {
2240 	if (t->rseq)
2241 		set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
2242 }
2243 
2244 void __rseq_handle_notify_resume(struct ksignal *sig, struct pt_regs *regs);
2245 
rseq_handle_notify_resume(struct ksignal * ksig,struct pt_regs * regs)2246 static inline void rseq_handle_notify_resume(struct ksignal *ksig,
2247 					     struct pt_regs *regs)
2248 {
2249 	if (current->rseq)
2250 		__rseq_handle_notify_resume(ksig, regs);
2251 }
2252 
rseq_signal_deliver(struct ksignal * ksig,struct pt_regs * regs)2253 static inline void rseq_signal_deliver(struct ksignal *ksig,
2254 				       struct pt_regs *regs)
2255 {
2256 	preempt_disable();
2257 	__set_bit(RSEQ_EVENT_SIGNAL_BIT, &current->rseq_event_mask);
2258 	preempt_enable();
2259 	rseq_handle_notify_resume(ksig, regs);
2260 }
2261 
2262 /* rseq_preempt() requires preemption to be disabled. */
rseq_preempt(struct task_struct * t)2263 static inline void rseq_preempt(struct task_struct *t)
2264 {
2265 	__set_bit(RSEQ_EVENT_PREEMPT_BIT, &t->rseq_event_mask);
2266 	rseq_set_notify_resume(t);
2267 }
2268 
2269 /* rseq_migrate() requires preemption to be disabled. */
rseq_migrate(struct task_struct * t)2270 static inline void rseq_migrate(struct task_struct *t)
2271 {
2272 	__set_bit(RSEQ_EVENT_MIGRATE_BIT, &t->rseq_event_mask);
2273 	rseq_set_notify_resume(t);
2274 }
2275 
2276 /*
2277  * If parent process has a registered restartable sequences area, the
2278  * child inherits. Unregister rseq for a clone with CLONE_VM set.
2279  */
rseq_fork(struct task_struct * t,unsigned long clone_flags)2280 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
2281 {
2282 	if (clone_flags & CLONE_VM) {
2283 		t->rseq = NULL;
2284 		t->rseq_sig = 0;
2285 		t->rseq_event_mask = 0;
2286 	} else {
2287 		t->rseq = current->rseq;
2288 		t->rseq_sig = current->rseq_sig;
2289 		t->rseq_event_mask = current->rseq_event_mask;
2290 	}
2291 }
2292 
rseq_execve(struct task_struct * t)2293 static inline void rseq_execve(struct task_struct *t)
2294 {
2295 	t->rseq = NULL;
2296 	t->rseq_sig = 0;
2297 	t->rseq_event_mask = 0;
2298 }
2299 
2300 #else
2301 
rseq_set_notify_resume(struct task_struct * t)2302 static inline void rseq_set_notify_resume(struct task_struct *t)
2303 {
2304 }
rseq_handle_notify_resume(struct ksignal * ksig,struct pt_regs * regs)2305 static inline void rseq_handle_notify_resume(struct ksignal *ksig,
2306 					     struct pt_regs *regs)
2307 {
2308 }
rseq_signal_deliver(struct ksignal * ksig,struct pt_regs * regs)2309 static inline void rseq_signal_deliver(struct ksignal *ksig,
2310 				       struct pt_regs *regs)
2311 {
2312 }
rseq_preempt(struct task_struct * t)2313 static inline void rseq_preempt(struct task_struct *t)
2314 {
2315 }
rseq_migrate(struct task_struct * t)2316 static inline void rseq_migrate(struct task_struct *t)
2317 {
2318 }
rseq_fork(struct task_struct * t,unsigned long clone_flags)2319 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
2320 {
2321 }
rseq_execve(struct task_struct * t)2322 static inline void rseq_execve(struct task_struct *t)
2323 {
2324 }
2325 
2326 #endif
2327 
2328 #ifdef CONFIG_DEBUG_RSEQ
2329 
2330 void rseq_syscall(struct pt_regs *regs);
2331 
2332 #else
2333 
rseq_syscall(struct pt_regs * regs)2334 static inline void rseq_syscall(struct pt_regs *regs)
2335 {
2336 }
2337 
2338 #endif
2339 
2340 const struct sched_avg *sched_trace_cfs_rq_avg(struct cfs_rq *cfs_rq);
2341 char *sched_trace_cfs_rq_path(struct cfs_rq *cfs_rq, char *str, int len);
2342 int sched_trace_cfs_rq_cpu(struct cfs_rq *cfs_rq);
2343 
2344 const struct sched_avg *sched_trace_rq_avg_rt(struct rq *rq);
2345 const struct sched_avg *sched_trace_rq_avg_dl(struct rq *rq);
2346 const struct sched_avg *sched_trace_rq_avg_irq(struct rq *rq);
2347 
2348 int sched_trace_rq_cpu(struct rq *rq);
2349 int sched_trace_rq_cpu_capacity(struct rq *rq);
2350 int sched_trace_rq_nr_running(struct rq *rq);
2351 
2352 const struct cpumask *sched_trace_rd_span(struct root_domain *rd);
2353 
2354 #ifdef CONFIG_SCHED_CORE
2355 extern void sched_core_free(struct task_struct *tsk);
2356 extern void sched_core_fork(struct task_struct *p);
2357 extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type,
2358 				unsigned long uaddr);
2359 #else
sched_core_free(struct task_struct * tsk)2360 static inline void sched_core_free(struct task_struct *tsk) { }
sched_core_fork(struct task_struct * p)2361 static inline void sched_core_fork(struct task_struct *p) { }
2362 #endif
2363 
2364 #endif
2365