xref: /openbmc/linux/include/linux/sched.h (revision 060f35a317ef09101b128f399dce7ed13d019461)
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/kmsan_types.h>
18 #include <linux/mutex.h>
19 #include <linux/plist.h>
20 #include <linux/hrtimer.h>
21 #include <linux/irqflags.h>
22 #include <linux/seccomp.h>
23 #include <linux/nodemask.h>
24 #include <linux/rcupdate.h>
25 #include <linux/refcount.h>
26 #include <linux/resource.h>
27 #include <linux/latencytop.h>
28 #include <linux/sched/prio.h>
29 #include <linux/sched/types.h>
30 #include <linux/signal_types.h>
31 #include <linux/syscall_user_dispatch.h>
32 #include <linux/mm_types_task.h>
33 #include <linux/task_io_accounting.h>
34 #include <linux/posix-timers.h>
35 #include <linux/rseq.h>
36 #include <linux/seqlock.h>
37 #include <linux/kcsan.h>
38 #include <linux/rv.h>
39 #include <linux/livepatch_sched.h>
40 #include <asm/kmap_size.h>
41 
42 /* task_struct member predeclarations (sorted alphabetically): */
43 struct audit_context;
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 seq_file;
67 struct sighand_struct;
68 struct signal_struct;
69 struct task_delay_info;
70 struct task_group;
71 struct user_event_mm;
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			0x00000000
86 #define TASK_INTERRUPTIBLE		0x00000001
87 #define TASK_UNINTERRUPTIBLE		0x00000002
88 #define __TASK_STOPPED			0x00000004
89 #define __TASK_TRACED			0x00000008
90 /* Used in tsk->exit_state: */
91 #define EXIT_DEAD			0x00000010
92 #define EXIT_ZOMBIE			0x00000020
93 #define EXIT_TRACE			(EXIT_ZOMBIE | EXIT_DEAD)
94 /* Used in tsk->__state again: */
95 #define TASK_PARKED			0x00000040
96 #define TASK_DEAD			0x00000080
97 #define TASK_WAKEKILL			0x00000100
98 #define TASK_WAKING			0x00000200
99 #define TASK_NOLOAD			0x00000400
100 #define TASK_NEW			0x00000800
101 #define TASK_RTLOCK_WAIT		0x00001000
102 #define TASK_FREEZABLE			0x00002000
103 #define __TASK_FREEZABLE_UNSAFE	       (0x00004000 * IS_ENABLED(CONFIG_LOCKDEP))
104 #define TASK_FROZEN			0x00008000
105 #define TASK_STATE_MAX			0x00010000
106 
107 #define TASK_ANY			(TASK_STATE_MAX-1)
108 
109 /*
110  * DO NOT ADD ANY NEW USERS !
111  */
112 #define TASK_FREEZABLE_UNSAFE		(TASK_FREEZABLE | __TASK_FREEZABLE_UNSAFE)
113 
114 /* Convenience macros for the sake of set_current_state: */
115 #define TASK_KILLABLE			(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
116 #define TASK_STOPPED			(TASK_WAKEKILL | __TASK_STOPPED)
117 #define TASK_TRACED			__TASK_TRACED
118 
119 #define TASK_IDLE			(TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
120 
121 /* Convenience macros for the sake of wake_up(): */
122 #define TASK_NORMAL			(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
123 
124 /* get_task_state(): */
125 #define TASK_REPORT			(TASK_RUNNING | TASK_INTERRUPTIBLE | \
126 					 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
127 					 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \
128 					 TASK_PARKED)
129 
130 #define task_is_running(task)		(READ_ONCE((task)->__state) == TASK_RUNNING)
131 
132 #define task_is_traced(task)		((READ_ONCE(task->jobctl) & JOBCTL_TRACED) != 0)
133 #define task_is_stopped(task)		((READ_ONCE(task->jobctl) & JOBCTL_STOPPED) != 0)
134 #define task_is_stopped_or_traced(task)	((READ_ONCE(task->jobctl) & (JOBCTL_STOPPED | JOBCTL_TRACED)) != 0)
135 
136 /*
137  * Special states are those that do not use the normal wait-loop pattern. See
138  * the comment with set_special_state().
139  */
140 #define is_special_task_state(state)				\
141 	((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | TASK_DEAD))
142 
143 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
144 # define debug_normal_state_change(state_value)				\
145 	do {								\
146 		WARN_ON_ONCE(is_special_task_state(state_value));	\
147 		current->task_state_change = _THIS_IP_;			\
148 	} while (0)
149 
150 # define debug_special_state_change(state_value)			\
151 	do {								\
152 		WARN_ON_ONCE(!is_special_task_state(state_value));	\
153 		current->task_state_change = _THIS_IP_;			\
154 	} while (0)
155 
156 # define debug_rtlock_wait_set_state()					\
157 	do {								 \
158 		current->saved_state_change = current->task_state_change;\
159 		current->task_state_change = _THIS_IP_;			 \
160 	} while (0)
161 
162 # define debug_rtlock_wait_restore_state()				\
163 	do {								 \
164 		current->task_state_change = current->saved_state_change;\
165 	} while (0)
166 
167 #else
168 # define debug_normal_state_change(cond)	do { } while (0)
169 # define debug_special_state_change(cond)	do { } while (0)
170 # define debug_rtlock_wait_set_state()		do { } while (0)
171 # define debug_rtlock_wait_restore_state()	do { } while (0)
172 #endif
173 
174 /*
175  * set_current_state() includes a barrier so that the write of current->__state
176  * is correctly serialised wrt the caller's subsequent test of whether to
177  * actually sleep:
178  *
179  *   for (;;) {
180  *	set_current_state(TASK_UNINTERRUPTIBLE);
181  *	if (CONDITION)
182  *	   break;
183  *
184  *	schedule();
185  *   }
186  *   __set_current_state(TASK_RUNNING);
187  *
188  * If the caller does not need such serialisation (because, for instance, the
189  * CONDITION test and condition change and wakeup are under the same lock) then
190  * use __set_current_state().
191  *
192  * The above is typically ordered against the wakeup, which does:
193  *
194  *   CONDITION = 1;
195  *   wake_up_state(p, TASK_UNINTERRUPTIBLE);
196  *
197  * where wake_up_state()/try_to_wake_up() executes a full memory barrier before
198  * accessing p->__state.
199  *
200  * Wakeup will do: if (@state & p->__state) p->__state = TASK_RUNNING, that is,
201  * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a
202  * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING).
203  *
204  * However, with slightly different timing the wakeup TASK_RUNNING store can
205  * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not
206  * a problem either because that will result in one extra go around the loop
207  * and our @cond test will save the day.
208  *
209  * Also see the comments of try_to_wake_up().
210  */
211 #define __set_current_state(state_value)				\
212 	do {								\
213 		debug_normal_state_change((state_value));		\
214 		WRITE_ONCE(current->__state, (state_value));		\
215 	} while (0)
216 
217 #define set_current_state(state_value)					\
218 	do {								\
219 		debug_normal_state_change((state_value));		\
220 		smp_store_mb(current->__state, (state_value));		\
221 	} while (0)
222 
223 /*
224  * set_special_state() should be used for those states when the blocking task
225  * can not use the regular condition based wait-loop. In that case we must
226  * serialize against wakeups such that any possible in-flight TASK_RUNNING
227  * stores will not collide with our state change.
228  */
229 #define set_special_state(state_value)					\
230 	do {								\
231 		unsigned long flags; /* may shadow */			\
232 									\
233 		raw_spin_lock_irqsave(&current->pi_lock, flags);	\
234 		debug_special_state_change((state_value));		\
235 		WRITE_ONCE(current->__state, (state_value));		\
236 		raw_spin_unlock_irqrestore(&current->pi_lock, flags);	\
237 	} while (0)
238 
239 /*
240  * PREEMPT_RT specific variants for "sleeping" spin/rwlocks
241  *
242  * RT's spin/rwlock substitutions are state preserving. The state of the
243  * task when blocking on the lock is saved in task_struct::saved_state and
244  * restored after the lock has been acquired.  These operations are
245  * serialized by task_struct::pi_lock against try_to_wake_up(). Any non RT
246  * lock related wakeups while the task is blocked on the lock are
247  * redirected to operate on task_struct::saved_state to ensure that these
248  * are not dropped. On restore task_struct::saved_state is set to
249  * TASK_RUNNING so any wakeup attempt redirected to saved_state will fail.
250  *
251  * The lock operation looks like this:
252  *
253  *	current_save_and_set_rtlock_wait_state();
254  *	for (;;) {
255  *		if (try_lock())
256  *			break;
257  *		raw_spin_unlock_irq(&lock->wait_lock);
258  *		schedule_rtlock();
259  *		raw_spin_lock_irq(&lock->wait_lock);
260  *		set_current_state(TASK_RTLOCK_WAIT);
261  *	}
262  *	current_restore_rtlock_saved_state();
263  */
264 #define current_save_and_set_rtlock_wait_state()			\
265 	do {								\
266 		lockdep_assert_irqs_disabled();				\
267 		raw_spin_lock(&current->pi_lock);			\
268 		current->saved_state = current->__state;		\
269 		debug_rtlock_wait_set_state();				\
270 		WRITE_ONCE(current->__state, TASK_RTLOCK_WAIT);		\
271 		raw_spin_unlock(&current->pi_lock);			\
272 	} while (0);
273 
274 #define current_restore_rtlock_saved_state()				\
275 	do {								\
276 		lockdep_assert_irqs_disabled();				\
277 		raw_spin_lock(&current->pi_lock);			\
278 		debug_rtlock_wait_restore_state();			\
279 		WRITE_ONCE(current->__state, current->saved_state);	\
280 		current->saved_state = TASK_RUNNING;			\
281 		raw_spin_unlock(&current->pi_lock);			\
282 	} while (0);
283 
284 #define get_current_state()	READ_ONCE(current->__state)
285 
286 /*
287  * Define the task command name length as enum, then it can be visible to
288  * BPF programs.
289  */
290 enum {
291 	TASK_COMM_LEN = 16,
292 };
293 
294 extern void scheduler_tick(void);
295 
296 #define	MAX_SCHEDULE_TIMEOUT		LONG_MAX
297 
298 extern long schedule_timeout(long timeout);
299 extern long schedule_timeout_interruptible(long timeout);
300 extern long schedule_timeout_killable(long timeout);
301 extern long schedule_timeout_uninterruptible(long timeout);
302 extern long schedule_timeout_idle(long timeout);
303 asmlinkage void schedule(void);
304 extern void schedule_preempt_disabled(void);
305 asmlinkage void preempt_schedule_irq(void);
306 #ifdef CONFIG_PREEMPT_RT
307  extern void schedule_rtlock(void);
308 #endif
309 
310 extern int __must_check io_schedule_prepare(void);
311 extern void io_schedule_finish(int token);
312 extern long io_schedule_timeout(long timeout);
313 extern void io_schedule(void);
314 
315 /**
316  * struct prev_cputime - snapshot of system and user cputime
317  * @utime: time spent in user mode
318  * @stime: time spent in system mode
319  * @lock: protects the above two fields
320  *
321  * Stores previous user/system time values such that we can guarantee
322  * monotonicity.
323  */
324 struct prev_cputime {
325 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
326 	u64				utime;
327 	u64				stime;
328 	raw_spinlock_t			lock;
329 #endif
330 };
331 
332 enum vtime_state {
333 	/* Task is sleeping or running in a CPU with VTIME inactive: */
334 	VTIME_INACTIVE = 0,
335 	/* Task is idle */
336 	VTIME_IDLE,
337 	/* Task runs in kernelspace in a CPU with VTIME active: */
338 	VTIME_SYS,
339 	/* Task runs in userspace in a CPU with VTIME active: */
340 	VTIME_USER,
341 	/* Task runs as guests in a CPU with VTIME active: */
342 	VTIME_GUEST,
343 };
344 
345 struct vtime {
346 	seqcount_t		seqcount;
347 	unsigned long long	starttime;
348 	enum vtime_state	state;
349 	unsigned int		cpu;
350 	u64			utime;
351 	u64			stime;
352 	u64			gtime;
353 };
354 
355 /*
356  * Utilization clamp constraints.
357  * @UCLAMP_MIN:	Minimum utilization
358  * @UCLAMP_MAX:	Maximum utilization
359  * @UCLAMP_CNT:	Utilization clamp constraints count
360  */
361 enum uclamp_id {
362 	UCLAMP_MIN = 0,
363 	UCLAMP_MAX,
364 	UCLAMP_CNT
365 };
366 
367 #ifdef CONFIG_SMP
368 extern struct root_domain def_root_domain;
369 extern struct mutex sched_domains_mutex;
370 #endif
371 
372 struct sched_param {
373 	int sched_priority;
374 };
375 
376 struct sched_info {
377 #ifdef CONFIG_SCHED_INFO
378 	/* Cumulative counters: */
379 
380 	/* # of times we have run on this CPU: */
381 	unsigned long			pcount;
382 
383 	/* Time spent waiting on a runqueue: */
384 	unsigned long long		run_delay;
385 
386 	/* Timestamps: */
387 
388 	/* When did we last run on a CPU? */
389 	unsigned long long		last_arrival;
390 
391 	/* When were we last queued to run? */
392 	unsigned long long		last_queued;
393 
394 #endif /* CONFIG_SCHED_INFO */
395 };
396 
397 /*
398  * Integer metrics need fixed point arithmetic, e.g., sched/fair
399  * has a few: load, load_avg, util_avg, freq, and capacity.
400  *
401  * We define a basic fixed point arithmetic range, and then formalize
402  * all these metrics based on that basic range.
403  */
404 # define SCHED_FIXEDPOINT_SHIFT		10
405 # define SCHED_FIXEDPOINT_SCALE		(1L << SCHED_FIXEDPOINT_SHIFT)
406 
407 /* Increase resolution of cpu_capacity calculations */
408 # define SCHED_CAPACITY_SHIFT		SCHED_FIXEDPOINT_SHIFT
409 # define SCHED_CAPACITY_SCALE		(1L << SCHED_CAPACITY_SHIFT)
410 
411 struct load_weight {
412 	unsigned long			weight;
413 	u32				inv_weight;
414 };
415 
416 /**
417  * struct util_est - Estimation utilization of FAIR tasks
418  * @enqueued: instantaneous estimated utilization of a task/cpu
419  * @ewma:     the Exponential Weighted Moving Average (EWMA)
420  *            utilization of a task
421  *
422  * Support data structure to track an Exponential Weighted Moving Average
423  * (EWMA) of a FAIR task's utilization. New samples are added to the moving
424  * average each time a task completes an activation. Sample's weight is chosen
425  * so that the EWMA will be relatively insensitive to transient changes to the
426  * task's workload.
427  *
428  * The enqueued attribute has a slightly different meaning for tasks and cpus:
429  * - task:   the task's util_avg at last task dequeue time
430  * - cfs_rq: the sum of util_est.enqueued for each RUNNABLE task on that CPU
431  * Thus, the util_est.enqueued of a task represents the contribution on the
432  * estimated utilization of the CPU where that task is currently enqueued.
433  *
434  * Only for tasks we track a moving average of the past instantaneous
435  * estimated utilization. This allows to absorb sporadic drops in utilization
436  * of an otherwise almost periodic task.
437  *
438  * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg
439  * updates. When a task is dequeued, its util_est should not be updated if its
440  * util_avg has not been updated in the meantime.
441  * This information is mapped into the MSB bit of util_est.enqueued at dequeue
442  * time. Since max value of util_est.enqueued for a task is 1024 (PELT util_avg
443  * for a task) it is safe to use MSB.
444  */
445 struct util_est {
446 	unsigned int			enqueued;
447 	unsigned int			ewma;
448 #define UTIL_EST_WEIGHT_SHIFT		2
449 #define UTIL_AVG_UNCHANGED		0x80000000
450 } __attribute__((__aligned__(sizeof(u64))));
451 
452 /*
453  * The load/runnable/util_avg accumulates an infinite geometric series
454  * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c).
455  *
456  * [load_avg definition]
457  *
458  *   load_avg = runnable% * scale_load_down(load)
459  *
460  * [runnable_avg definition]
461  *
462  *   runnable_avg = runnable% * SCHED_CAPACITY_SCALE
463  *
464  * [util_avg definition]
465  *
466  *   util_avg = running% * SCHED_CAPACITY_SCALE
467  *
468  * where runnable% is the time ratio that a sched_entity is runnable and
469  * running% the time ratio that a sched_entity is running.
470  *
471  * For cfs_rq, they are the aggregated values of all runnable and blocked
472  * sched_entities.
473  *
474  * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU
475  * capacity scaling. The scaling is done through the rq_clock_pelt that is used
476  * for computing those signals (see update_rq_clock_pelt())
477  *
478  * N.B., the above ratios (runnable% and running%) themselves are in the
479  * range of [0, 1]. To do fixed point arithmetics, we therefore scale them
480  * to as large a range as necessary. This is for example reflected by
481  * util_avg's SCHED_CAPACITY_SCALE.
482  *
483  * [Overflow issue]
484  *
485  * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
486  * with the highest load (=88761), always runnable on a single cfs_rq,
487  * and should not overflow as the number already hits PID_MAX_LIMIT.
488  *
489  * For all other cases (including 32-bit kernels), struct load_weight's
490  * weight will overflow first before we do, because:
491  *
492  *    Max(load_avg) <= Max(load.weight)
493  *
494  * Then it is the load_weight's responsibility to consider overflow
495  * issues.
496  */
497 struct sched_avg {
498 	u64				last_update_time;
499 	u64				load_sum;
500 	u64				runnable_sum;
501 	u32				util_sum;
502 	u32				period_contrib;
503 	unsigned long			load_avg;
504 	unsigned long			runnable_avg;
505 	unsigned long			util_avg;
506 	struct util_est			util_est;
507 } ____cacheline_aligned;
508 
509 struct sched_statistics {
510 #ifdef CONFIG_SCHEDSTATS
511 	u64				wait_start;
512 	u64				wait_max;
513 	u64				wait_count;
514 	u64				wait_sum;
515 	u64				iowait_count;
516 	u64				iowait_sum;
517 
518 	u64				sleep_start;
519 	u64				sleep_max;
520 	s64				sum_sleep_runtime;
521 
522 	u64				block_start;
523 	u64				block_max;
524 	s64				sum_block_runtime;
525 
526 	s64				exec_max;
527 	u64				slice_max;
528 
529 	u64				nr_migrations_cold;
530 	u64				nr_failed_migrations_affine;
531 	u64				nr_failed_migrations_running;
532 	u64				nr_failed_migrations_hot;
533 	u64				nr_forced_migrations;
534 
535 	u64				nr_wakeups;
536 	u64				nr_wakeups_sync;
537 	u64				nr_wakeups_migrate;
538 	u64				nr_wakeups_local;
539 	u64				nr_wakeups_remote;
540 	u64				nr_wakeups_affine;
541 	u64				nr_wakeups_affine_attempts;
542 	u64				nr_wakeups_passive;
543 	u64				nr_wakeups_idle;
544 
545 #ifdef CONFIG_SCHED_CORE
546 	u64				core_forceidle_sum;
547 #endif
548 #endif /* CONFIG_SCHEDSTATS */
549 } ____cacheline_aligned;
550 
551 struct sched_entity {
552 	/* For load-balancing: */
553 	struct load_weight		load;
554 	struct rb_node			run_node;
555 	u64				deadline;
556 	u64				min_deadline;
557 
558 	struct list_head		group_node;
559 	unsigned int			on_rq;
560 
561 	u64				exec_start;
562 	u64				sum_exec_runtime;
563 	u64				prev_sum_exec_runtime;
564 	u64				vruntime;
565 	s64				vlag;
566 	u64				slice;
567 
568 	u64				nr_migrations;
569 
570 #ifdef CONFIG_FAIR_GROUP_SCHED
571 	int				depth;
572 	struct sched_entity		*parent;
573 	/* rq on which this entity is (to be) queued: */
574 	struct cfs_rq			*cfs_rq;
575 	/* rq "owned" by this entity/group: */
576 	struct cfs_rq			*my_q;
577 	/* cached value of my_q->h_nr_running */
578 	unsigned long			runnable_weight;
579 #endif
580 
581 #ifdef CONFIG_SMP
582 	/*
583 	 * Per entity load average tracking.
584 	 *
585 	 * Put into separate cache line so it does not
586 	 * collide with read-mostly values above.
587 	 */
588 	struct sched_avg		avg;
589 #endif
590 };
591 
592 struct sched_rt_entity {
593 	struct list_head		run_list;
594 	unsigned long			timeout;
595 	unsigned long			watchdog_stamp;
596 	unsigned int			time_slice;
597 	unsigned short			on_rq;
598 	unsigned short			on_list;
599 
600 	struct sched_rt_entity		*back;
601 #ifdef CONFIG_RT_GROUP_SCHED
602 	struct sched_rt_entity		*parent;
603 	/* rq on which this entity is (to be) queued: */
604 	struct rt_rq			*rt_rq;
605 	/* rq "owned" by this entity/group: */
606 	struct rt_rq			*my_q;
607 #endif
608 } __randomize_layout;
609 
610 struct sched_dl_entity {
611 	struct rb_node			rb_node;
612 
613 	/*
614 	 * Original scheduling parameters. Copied here from sched_attr
615 	 * during sched_setattr(), they will remain the same until
616 	 * the next sched_setattr().
617 	 */
618 	u64				dl_runtime;	/* Maximum runtime for each instance	*/
619 	u64				dl_deadline;	/* Relative deadline of each instance	*/
620 	u64				dl_period;	/* Separation of two instances (period) */
621 	u64				dl_bw;		/* dl_runtime / dl_period		*/
622 	u64				dl_density;	/* dl_runtime / dl_deadline		*/
623 
624 	/*
625 	 * Actual scheduling parameters. Initialized with the values above,
626 	 * they are continuously updated during task execution. Note that
627 	 * the remaining runtime could be < 0 in case we are in overrun.
628 	 */
629 	s64				runtime;	/* Remaining runtime for this instance	*/
630 	u64				deadline;	/* Absolute deadline for this instance	*/
631 	unsigned int			flags;		/* Specifying the scheduler behaviour	*/
632 
633 	/*
634 	 * Some bool flags:
635 	 *
636 	 * @dl_throttled tells if we exhausted the runtime. If so, the
637 	 * task has to wait for a replenishment to be performed at the
638 	 * next firing of dl_timer.
639 	 *
640 	 * @dl_yielded tells if task gave up the CPU before consuming
641 	 * all its available runtime during the last job.
642 	 *
643 	 * @dl_non_contending tells if the task is inactive while still
644 	 * contributing to the active utilization. In other words, it
645 	 * indicates if the inactive timer has been armed and its handler
646 	 * has not been executed yet. This flag is useful to avoid race
647 	 * conditions between the inactive timer handler and the wakeup
648 	 * code.
649 	 *
650 	 * @dl_overrun tells if the task asked to be informed about runtime
651 	 * overruns.
652 	 */
653 	unsigned int			dl_throttled      : 1;
654 	unsigned int			dl_yielded        : 1;
655 	unsigned int			dl_non_contending : 1;
656 	unsigned int			dl_overrun	  : 1;
657 
658 	/*
659 	 * Bandwidth enforcement timer. Each -deadline task has its
660 	 * own bandwidth to be enforced, thus we need one timer per task.
661 	 */
662 	struct hrtimer			dl_timer;
663 
664 	/*
665 	 * Inactive timer, responsible for decreasing the active utilization
666 	 * at the "0-lag time". When a -deadline task blocks, it contributes
667 	 * to GRUB's active utilization until the "0-lag time", hence a
668 	 * timer is needed to decrease the active utilization at the correct
669 	 * time.
670 	 */
671 	struct hrtimer inactive_timer;
672 
673 #ifdef CONFIG_RT_MUTEXES
674 	/*
675 	 * Priority Inheritance. When a DEADLINE scheduling entity is boosted
676 	 * pi_se points to the donor, otherwise points to the dl_se it belongs
677 	 * to (the original one/itself).
678 	 */
679 	struct sched_dl_entity *pi_se;
680 #endif
681 };
682 
683 #ifdef CONFIG_UCLAMP_TASK
684 /* Number of utilization clamp buckets (shorter alias) */
685 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT
686 
687 /*
688  * Utilization clamp for a scheduling entity
689  * @value:		clamp value "assigned" to a se
690  * @bucket_id:		bucket index corresponding to the "assigned" value
691  * @active:		the se is currently refcounted in a rq's bucket
692  * @user_defined:	the requested clamp value comes from user-space
693  *
694  * The bucket_id is the index of the clamp bucket matching the clamp value
695  * which is pre-computed and stored to avoid expensive integer divisions from
696  * the fast path.
697  *
698  * The active bit is set whenever a task has got an "effective" value assigned,
699  * which can be different from the clamp value "requested" from user-space.
700  * This allows to know a task is refcounted in the rq's bucket corresponding
701  * to the "effective" bucket_id.
702  *
703  * The user_defined bit is set whenever a task has got a task-specific clamp
704  * value requested from userspace, i.e. the system defaults apply to this task
705  * just as a restriction. This allows to relax default clamps when a less
706  * restrictive task-specific value has been requested, thus allowing to
707  * implement a "nice" semantic. For example, a task running with a 20%
708  * default boost can still drop its own boosting to 0%.
709  */
710 struct uclamp_se {
711 	unsigned int value		: bits_per(SCHED_CAPACITY_SCALE);
712 	unsigned int bucket_id		: bits_per(UCLAMP_BUCKETS);
713 	unsigned int active		: 1;
714 	unsigned int user_defined	: 1;
715 };
716 #endif /* CONFIG_UCLAMP_TASK */
717 
718 union rcu_special {
719 	struct {
720 		u8			blocked;
721 		u8			need_qs;
722 		u8			exp_hint; /* Hint for performance. */
723 		u8			need_mb; /* Readers need smp_mb(). */
724 	} b; /* Bits. */
725 	u32 s; /* Set of bits. */
726 };
727 
728 enum perf_event_task_context {
729 	perf_invalid_context = -1,
730 	perf_hw_context = 0,
731 	perf_sw_context,
732 	perf_nr_task_contexts,
733 };
734 
735 struct wake_q_node {
736 	struct wake_q_node *next;
737 };
738 
739 struct kmap_ctrl {
740 #ifdef CONFIG_KMAP_LOCAL
741 	int				idx;
742 	pte_t				pteval[KM_MAX_IDX];
743 #endif
744 };
745 
746 struct task_struct {
747 #ifdef CONFIG_THREAD_INFO_IN_TASK
748 	/*
749 	 * For reasons of header soup (see current_thread_info()), this
750 	 * must be the first element of task_struct.
751 	 */
752 	struct thread_info		thread_info;
753 #endif
754 	unsigned int			__state;
755 
756 #ifdef CONFIG_PREEMPT_RT
757 	/* saved state for "spinlock sleepers" */
758 	unsigned int			saved_state;
759 #endif
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 	const struct sched_class	*sched_class;
801 
802 #ifdef CONFIG_SCHED_CORE
803 	struct rb_node			core_node;
804 	unsigned long			core_cookie;
805 	unsigned int			core_occupation;
806 #endif
807 
808 #ifdef CONFIG_CGROUP_SCHED
809 	struct task_group		*sched_task_group;
810 #endif
811 
812 #ifdef CONFIG_UCLAMP_TASK
813 	/*
814 	 * Clamp values requested for a scheduling entity.
815 	 * Must be updated with task_rq_lock() held.
816 	 */
817 	struct uclamp_se		uclamp_req[UCLAMP_CNT];
818 	/*
819 	 * Effective clamp values used for a scheduling entity.
820 	 * Must be updated with task_rq_lock() held.
821 	 */
822 	struct uclamp_se		uclamp[UCLAMP_CNT];
823 #endif
824 
825 	struct sched_statistics         stats;
826 
827 #ifdef CONFIG_PREEMPT_NOTIFIERS
828 	/* List of struct preempt_notifier: */
829 	struct hlist_head		preempt_notifiers;
830 #endif
831 
832 #ifdef CONFIG_BLK_DEV_IO_TRACE
833 	unsigned int			btrace_seq;
834 #endif
835 
836 	unsigned int			policy;
837 	int				nr_cpus_allowed;
838 	const cpumask_t			*cpus_ptr;
839 	cpumask_t			*user_cpus_ptr;
840 	cpumask_t			cpus_mask;
841 	void				*migration_pending;
842 #ifdef CONFIG_SMP
843 	unsigned short			migration_disabled;
844 #endif
845 	unsigned short			migration_flags;
846 
847 #ifdef CONFIG_PREEMPT_RCU
848 	int				rcu_read_lock_nesting;
849 	union rcu_special		rcu_read_unlock_special;
850 	struct list_head		rcu_node_entry;
851 	struct rcu_node			*rcu_blocked_node;
852 #endif /* #ifdef CONFIG_PREEMPT_RCU */
853 
854 #ifdef CONFIG_TASKS_RCU
855 	unsigned long			rcu_tasks_nvcsw;
856 	u8				rcu_tasks_holdout;
857 	u8				rcu_tasks_idx;
858 	int				rcu_tasks_idle_cpu;
859 	struct list_head		rcu_tasks_holdout_list;
860 	int				rcu_tasks_exit_cpu;
861 	struct list_head		rcu_tasks_exit_list;
862 #endif /* #ifdef CONFIG_TASKS_RCU */
863 
864 #ifdef CONFIG_TASKS_TRACE_RCU
865 	int				trc_reader_nesting;
866 	int				trc_ipi_to_cpu;
867 	union rcu_special		trc_reader_special;
868 	struct list_head		trc_holdout_list;
869 	struct list_head		trc_blkd_node;
870 	int				trc_blkd_cpu;
871 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */
872 
873 	struct sched_info		sched_info;
874 
875 	struct list_head		tasks;
876 #ifdef CONFIG_SMP
877 	struct plist_node		pushable_tasks;
878 	struct rb_node			pushable_dl_tasks;
879 #endif
880 
881 	struct mm_struct		*mm;
882 	struct mm_struct		*active_mm;
883 
884 	int				exit_state;
885 	int				exit_code;
886 	int				exit_signal;
887 	/* The signal sent when the parent dies: */
888 	int				pdeath_signal;
889 	/* JOBCTL_*, siglock protected: */
890 	unsigned long			jobctl;
891 
892 	/* Used for emulating ABI behavior of previous Linux versions: */
893 	unsigned int			personality;
894 
895 	/* Scheduler bits, serialized by scheduler locks: */
896 	unsigned			sched_reset_on_fork:1;
897 	unsigned			sched_contributes_to_load:1;
898 	unsigned			sched_migrated:1;
899 	unsigned			sched_task_hot:1;
900 
901 	/* Force alignment to the next boundary: */
902 	unsigned			:0;
903 
904 	/* Unserialized, strictly 'current' */
905 
906 	/*
907 	 * This field must not be in the scheduler word above due to wakelist
908 	 * queueing no longer being serialized by p->on_cpu. However:
909 	 *
910 	 * p->XXX = X;			ttwu()
911 	 * schedule()			  if (p->on_rq && ..) // false
912 	 *   smp_mb__after_spinlock();	  if (smp_load_acquire(&p->on_cpu) && //true
913 	 *   deactivate_task()		      ttwu_queue_wakelist())
914 	 *     p->on_rq = 0;			p->sched_remote_wakeup = Y;
915 	 *
916 	 * guarantees all stores of 'current' are visible before
917 	 * ->sched_remote_wakeup gets used, so it can be in this word.
918 	 */
919 	unsigned			sched_remote_wakeup:1;
920 
921 	/* Bit to tell LSMs we're in execve(): */
922 	unsigned			in_execve:1;
923 	unsigned			in_iowait:1;
924 #ifndef TIF_RESTORE_SIGMASK
925 	unsigned			restore_sigmask:1;
926 #endif
927 #ifdef CONFIG_MEMCG
928 	unsigned			in_user_fault:1;
929 #endif
930 #ifdef CONFIG_LRU_GEN
931 	/* whether the LRU algorithm may apply to this access */
932 	unsigned			in_lru_fault:1;
933 #endif
934 #ifdef CONFIG_COMPAT_BRK
935 	unsigned			brk_randomized:1;
936 #endif
937 #ifdef CONFIG_CGROUPS
938 	/* disallow userland-initiated cgroup migration */
939 	unsigned			no_cgroup_migration:1;
940 	/* task is frozen/stopped (used by the cgroup freezer) */
941 	unsigned			frozen:1;
942 #endif
943 #ifdef CONFIG_BLK_CGROUP
944 	unsigned			use_memdelay:1;
945 #endif
946 #ifdef CONFIG_PSI
947 	/* Stalled due to lack of memory */
948 	unsigned			in_memstall:1;
949 #endif
950 #ifdef CONFIG_PAGE_OWNER
951 	/* Used by page_owner=on to detect recursion in page tracking. */
952 	unsigned			in_page_owner:1;
953 #endif
954 #ifdef CONFIG_EVENTFD
955 	/* Recursion prevention for eventfd_signal() */
956 	unsigned			in_eventfd:1;
957 #endif
958 #ifdef CONFIG_IOMMU_SVA
959 	unsigned			pasid_activated:1;
960 #endif
961 #ifdef	CONFIG_CPU_SUP_INTEL
962 	unsigned			reported_split_lock:1;
963 #endif
964 #ifdef CONFIG_TASK_DELAY_ACCT
965 	/* delay due to memory thrashing */
966 	unsigned                        in_thrashing:1;
967 #endif
968 
969 	unsigned long			atomic_flags; /* Flags requiring atomic access. */
970 
971 	struct restart_block		restart_block;
972 
973 	pid_t				pid;
974 	pid_t				tgid;
975 
976 #ifdef CONFIG_STACKPROTECTOR
977 	/* Canary value for the -fstack-protector GCC feature: */
978 	unsigned long			stack_canary;
979 #endif
980 	/*
981 	 * Pointers to the (original) parent process, youngest child, younger sibling,
982 	 * older sibling, respectively.  (p->father can be replaced with
983 	 * p->real_parent->pid)
984 	 */
985 
986 	/* Real parent process: */
987 	struct task_struct __rcu	*real_parent;
988 
989 	/* Recipient of SIGCHLD, wait4() reports: */
990 	struct task_struct __rcu	*parent;
991 
992 	/*
993 	 * Children/sibling form the list of natural children:
994 	 */
995 	struct list_head		children;
996 	struct list_head		sibling;
997 	struct task_struct		*group_leader;
998 
999 	/*
1000 	 * 'ptraced' is the list of tasks this task is using ptrace() on.
1001 	 *
1002 	 * This includes both natural children and PTRACE_ATTACH targets.
1003 	 * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
1004 	 */
1005 	struct list_head		ptraced;
1006 	struct list_head		ptrace_entry;
1007 
1008 	/* PID/PID hash table linkage. */
1009 	struct pid			*thread_pid;
1010 	struct hlist_node		pid_links[PIDTYPE_MAX];
1011 	struct list_head		thread_group;
1012 	struct list_head		thread_node;
1013 
1014 	struct completion		*vfork_done;
1015 
1016 	/* CLONE_CHILD_SETTID: */
1017 	int __user			*set_child_tid;
1018 
1019 	/* CLONE_CHILD_CLEARTID: */
1020 	int __user			*clear_child_tid;
1021 
1022 	/* PF_KTHREAD | PF_IO_WORKER */
1023 	void				*worker_private;
1024 
1025 	u64				utime;
1026 	u64				stime;
1027 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
1028 	u64				utimescaled;
1029 	u64				stimescaled;
1030 #endif
1031 	u64				gtime;
1032 	struct prev_cputime		prev_cputime;
1033 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1034 	struct vtime			vtime;
1035 #endif
1036 
1037 #ifdef CONFIG_NO_HZ_FULL
1038 	atomic_t			tick_dep_mask;
1039 #endif
1040 	/* Context switch counts: */
1041 	unsigned long			nvcsw;
1042 	unsigned long			nivcsw;
1043 
1044 	/* Monotonic time in nsecs: */
1045 	u64				start_time;
1046 
1047 	/* Boot based time in nsecs: */
1048 	u64				start_boottime;
1049 
1050 	/* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
1051 	unsigned long			min_flt;
1052 	unsigned long			maj_flt;
1053 
1054 	/* Empty if CONFIG_POSIX_CPUTIMERS=n */
1055 	struct posix_cputimers		posix_cputimers;
1056 
1057 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK
1058 	struct posix_cputimers_work	posix_cputimers_work;
1059 #endif
1060 
1061 	/* Process credentials: */
1062 
1063 	/* Tracer's credentials at attach: */
1064 	const struct cred __rcu		*ptracer_cred;
1065 
1066 	/* Objective and real subjective task credentials (COW): */
1067 	const struct cred __rcu		*real_cred;
1068 
1069 	/* Effective (overridable) subjective task credentials (COW): */
1070 	const struct cred __rcu		*cred;
1071 
1072 #ifdef CONFIG_KEYS
1073 	/* Cached requested key. */
1074 	struct key			*cached_requested_key;
1075 #endif
1076 
1077 	/*
1078 	 * executable name, excluding path.
1079 	 *
1080 	 * - normally initialized setup_new_exec()
1081 	 * - access it with [gs]et_task_comm()
1082 	 * - lock it with task_lock()
1083 	 */
1084 	char				comm[TASK_COMM_LEN];
1085 
1086 	struct nameidata		*nameidata;
1087 
1088 #ifdef CONFIG_SYSVIPC
1089 	struct sysv_sem			sysvsem;
1090 	struct sysv_shm			sysvshm;
1091 #endif
1092 #ifdef CONFIG_DETECT_HUNG_TASK
1093 	unsigned long			last_switch_count;
1094 	unsigned long			last_switch_time;
1095 #endif
1096 	/* Filesystem information: */
1097 	struct fs_struct		*fs;
1098 
1099 	/* Open file information: */
1100 	struct files_struct		*files;
1101 
1102 #ifdef CONFIG_IO_URING
1103 	struct io_uring_task		*io_uring;
1104 #endif
1105 
1106 	/* Namespaces: */
1107 	struct nsproxy			*nsproxy;
1108 
1109 	/* Signal handlers: */
1110 	struct signal_struct		*signal;
1111 	struct sighand_struct __rcu		*sighand;
1112 	sigset_t			blocked;
1113 	sigset_t			real_blocked;
1114 	/* Restored if set_restore_sigmask() was used: */
1115 	sigset_t			saved_sigmask;
1116 	struct sigpending		pending;
1117 	unsigned long			sas_ss_sp;
1118 	size_t				sas_ss_size;
1119 	unsigned int			sas_ss_flags;
1120 
1121 	struct callback_head		*task_works;
1122 
1123 #ifdef CONFIG_AUDIT
1124 #ifdef CONFIG_AUDITSYSCALL
1125 	struct audit_context		*audit_context;
1126 #endif
1127 	kuid_t				loginuid;
1128 	unsigned int			sessionid;
1129 #endif
1130 	struct seccomp			seccomp;
1131 	struct syscall_user_dispatch	syscall_dispatch;
1132 
1133 	/* Thread group tracking: */
1134 	u64				parent_exec_id;
1135 	u64				self_exec_id;
1136 
1137 	/* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
1138 	spinlock_t			alloc_lock;
1139 
1140 	/* Protection of the PI data structures: */
1141 	raw_spinlock_t			pi_lock;
1142 
1143 	struct wake_q_node		wake_q;
1144 
1145 #ifdef CONFIG_RT_MUTEXES
1146 	/* PI waiters blocked on a rt_mutex held by this task: */
1147 	struct rb_root_cached		pi_waiters;
1148 	/* Updated under owner's pi_lock and rq lock */
1149 	struct task_struct		*pi_top_task;
1150 	/* Deadlock detection and priority inheritance handling: */
1151 	struct rt_mutex_waiter		*pi_blocked_on;
1152 #endif
1153 
1154 #ifdef CONFIG_DEBUG_MUTEXES
1155 	/* Mutex deadlock detection: */
1156 	struct mutex_waiter		*blocked_on;
1157 #endif
1158 
1159 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1160 	int				non_block_count;
1161 #endif
1162 
1163 #ifdef CONFIG_TRACE_IRQFLAGS
1164 	struct irqtrace_events		irqtrace;
1165 	unsigned int			hardirq_threaded;
1166 	u64				hardirq_chain_key;
1167 	int				softirqs_enabled;
1168 	int				softirq_context;
1169 	int				irq_config;
1170 #endif
1171 #ifdef CONFIG_PREEMPT_RT
1172 	int				softirq_disable_cnt;
1173 #endif
1174 
1175 #ifdef CONFIG_LOCKDEP
1176 # define MAX_LOCK_DEPTH			48UL
1177 	u64				curr_chain_key;
1178 	int				lockdep_depth;
1179 	unsigned int			lockdep_recursion;
1180 	struct held_lock		held_locks[MAX_LOCK_DEPTH];
1181 #endif
1182 
1183 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP)
1184 	unsigned int			in_ubsan;
1185 #endif
1186 
1187 	/* Journalling filesystem info: */
1188 	void				*journal_info;
1189 
1190 	/* Stacked block device info: */
1191 	struct bio_list			*bio_list;
1192 
1193 	/* Stack plugging: */
1194 	struct blk_plug			*plug;
1195 
1196 	/* VM state: */
1197 	struct reclaim_state		*reclaim_state;
1198 
1199 	struct io_context		*io_context;
1200 
1201 #ifdef CONFIG_COMPACTION
1202 	struct capture_control		*capture_control;
1203 #endif
1204 	/* Ptrace state: */
1205 	unsigned long			ptrace_message;
1206 	kernel_siginfo_t		*last_siginfo;
1207 
1208 	struct task_io_accounting	ioac;
1209 #ifdef CONFIG_PSI
1210 	/* Pressure stall state */
1211 	unsigned int			psi_flags;
1212 #endif
1213 #ifdef CONFIG_TASK_XACCT
1214 	/* Accumulated RSS usage: */
1215 	u64				acct_rss_mem1;
1216 	/* Accumulated virtual memory usage: */
1217 	u64				acct_vm_mem1;
1218 	/* stime + utime since last update: */
1219 	u64				acct_timexpd;
1220 #endif
1221 #ifdef CONFIG_CPUSETS
1222 	/* Protected by ->alloc_lock: */
1223 	nodemask_t			mems_allowed;
1224 	/* Sequence number to catch updates: */
1225 	seqcount_spinlock_t		mems_allowed_seq;
1226 	int				cpuset_mem_spread_rotor;
1227 	int				cpuset_slab_spread_rotor;
1228 #endif
1229 #ifdef CONFIG_CGROUPS
1230 	/* Control Group info protected by css_set_lock: */
1231 	struct css_set __rcu		*cgroups;
1232 	/* cg_list protected by css_set_lock and tsk->alloc_lock: */
1233 	struct list_head		cg_list;
1234 #endif
1235 #ifdef CONFIG_X86_CPU_RESCTRL
1236 	u32				closid;
1237 	u32				rmid;
1238 #endif
1239 #ifdef CONFIG_FUTEX
1240 	struct robust_list_head __user	*robust_list;
1241 #ifdef CONFIG_COMPAT
1242 	struct compat_robust_list_head __user *compat_robust_list;
1243 #endif
1244 	struct list_head		pi_state_list;
1245 	struct futex_pi_state		*pi_state_cache;
1246 	struct mutex			futex_exit_mutex;
1247 	unsigned int			futex_state;
1248 #endif
1249 #ifdef CONFIG_PERF_EVENTS
1250 	struct perf_event_context	*perf_event_ctxp;
1251 	struct mutex			perf_event_mutex;
1252 	struct list_head		perf_event_list;
1253 #endif
1254 #ifdef CONFIG_DEBUG_PREEMPT
1255 	unsigned long			preempt_disable_ip;
1256 #endif
1257 #ifdef CONFIG_NUMA
1258 	/* Protected by alloc_lock: */
1259 	struct mempolicy		*mempolicy;
1260 	short				il_prev;
1261 	short				pref_node_fork;
1262 #endif
1263 #ifdef CONFIG_NUMA_BALANCING
1264 	int				numa_scan_seq;
1265 	unsigned int			numa_scan_period;
1266 	unsigned int			numa_scan_period_max;
1267 	int				numa_preferred_nid;
1268 	unsigned long			numa_migrate_retry;
1269 	/* Migration stamp: */
1270 	u64				node_stamp;
1271 	u64				last_task_numa_placement;
1272 	u64				last_sum_exec_runtime;
1273 	struct callback_head		numa_work;
1274 
1275 	/*
1276 	 * This pointer is only modified for current in syscall and
1277 	 * pagefault context (and for tasks being destroyed), so it can be read
1278 	 * from any of the following contexts:
1279 	 *  - RCU read-side critical section
1280 	 *  - current->numa_group from everywhere
1281 	 *  - task's runqueue locked, task not running
1282 	 */
1283 	struct numa_group __rcu		*numa_group;
1284 
1285 	/*
1286 	 * numa_faults is an array split into four regions:
1287 	 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1288 	 * in this precise order.
1289 	 *
1290 	 * faults_memory: Exponential decaying average of faults on a per-node
1291 	 * basis. Scheduling placement decisions are made based on these
1292 	 * counts. The values remain static for the duration of a PTE scan.
1293 	 * faults_cpu: Track the nodes the process was running on when a NUMA
1294 	 * hinting fault was incurred.
1295 	 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1296 	 * during the current scan window. When the scan completes, the counts
1297 	 * in faults_memory and faults_cpu decay and these values are copied.
1298 	 */
1299 	unsigned long			*numa_faults;
1300 	unsigned long			total_numa_faults;
1301 
1302 	/*
1303 	 * numa_faults_locality tracks if faults recorded during the last
1304 	 * scan window were remote/local or failed to migrate. The task scan
1305 	 * period is adapted based on the locality of the faults with different
1306 	 * weights depending on whether they were shared or private faults
1307 	 */
1308 	unsigned long			numa_faults_locality[3];
1309 
1310 	unsigned long			numa_pages_migrated;
1311 #endif /* CONFIG_NUMA_BALANCING */
1312 
1313 #ifdef CONFIG_RSEQ
1314 	struct rseq __user *rseq;
1315 	u32 rseq_len;
1316 	u32 rseq_sig;
1317 	/*
1318 	 * RmW on rseq_event_mask must be performed atomically
1319 	 * with respect to preemption.
1320 	 */
1321 	unsigned long rseq_event_mask;
1322 #endif
1323 
1324 #ifdef CONFIG_SCHED_MM_CID
1325 	int				mm_cid;		/* Current cid in mm */
1326 	int				last_mm_cid;	/* Most recent cid in mm */
1327 	int				migrate_from_cpu;
1328 	int				mm_cid_active;	/* Whether cid bitmap is active */
1329 	struct callback_head		cid_work;
1330 #endif
1331 
1332 	struct tlbflush_unmap_batch	tlb_ubc;
1333 
1334 	/* Cache last used pipe for splice(): */
1335 	struct pipe_inode_info		*splice_pipe;
1336 
1337 	struct page_frag		task_frag;
1338 
1339 #ifdef CONFIG_TASK_DELAY_ACCT
1340 	struct task_delay_info		*delays;
1341 #endif
1342 
1343 #ifdef CONFIG_FAULT_INJECTION
1344 	int				make_it_fail;
1345 	unsigned int			fail_nth;
1346 #endif
1347 	/*
1348 	 * When (nr_dirtied >= nr_dirtied_pause), it's time to call
1349 	 * balance_dirty_pages() for a dirty throttling pause:
1350 	 */
1351 	int				nr_dirtied;
1352 	int				nr_dirtied_pause;
1353 	/* Start of a write-and-pause period: */
1354 	unsigned long			dirty_paused_when;
1355 
1356 #ifdef CONFIG_LATENCYTOP
1357 	int				latency_record_count;
1358 	struct latency_record		latency_record[LT_SAVECOUNT];
1359 #endif
1360 	/*
1361 	 * Time slack values; these are used to round up poll() and
1362 	 * select() etc timeout values. These are in nanoseconds.
1363 	 */
1364 	u64				timer_slack_ns;
1365 	u64				default_timer_slack_ns;
1366 
1367 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
1368 	unsigned int			kasan_depth;
1369 #endif
1370 
1371 #ifdef CONFIG_KCSAN
1372 	struct kcsan_ctx		kcsan_ctx;
1373 #ifdef CONFIG_TRACE_IRQFLAGS
1374 	struct irqtrace_events		kcsan_save_irqtrace;
1375 #endif
1376 #ifdef CONFIG_KCSAN_WEAK_MEMORY
1377 	int				kcsan_stack_depth;
1378 #endif
1379 #endif
1380 
1381 #ifdef CONFIG_KMSAN
1382 	struct kmsan_ctx		kmsan_ctx;
1383 #endif
1384 
1385 #if IS_ENABLED(CONFIG_KUNIT)
1386 	struct kunit			*kunit_test;
1387 #endif
1388 
1389 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1390 	/* Index of current stored address in ret_stack: */
1391 	int				curr_ret_stack;
1392 	int				curr_ret_depth;
1393 
1394 	/* Stack of return addresses for return function tracing: */
1395 	struct ftrace_ret_stack		*ret_stack;
1396 
1397 	/* Timestamp for last schedule: */
1398 	unsigned long long		ftrace_timestamp;
1399 
1400 	/*
1401 	 * Number of functions that haven't been traced
1402 	 * because of depth overrun:
1403 	 */
1404 	atomic_t			trace_overrun;
1405 
1406 	/* Pause tracing: */
1407 	atomic_t			tracing_graph_pause;
1408 #endif
1409 
1410 #ifdef CONFIG_TRACING
1411 	/* Bitmask and counter of trace recursion: */
1412 	unsigned long			trace_recursion;
1413 #endif /* CONFIG_TRACING */
1414 
1415 #ifdef CONFIG_KCOV
1416 	/* See kernel/kcov.c for more details. */
1417 
1418 	/* Coverage collection mode enabled for this task (0 if disabled): */
1419 	unsigned int			kcov_mode;
1420 
1421 	/* Size of the kcov_area: */
1422 	unsigned int			kcov_size;
1423 
1424 	/* Buffer for coverage collection: */
1425 	void				*kcov_area;
1426 
1427 	/* KCOV descriptor wired with this task or NULL: */
1428 	struct kcov			*kcov;
1429 
1430 	/* KCOV common handle for remote coverage collection: */
1431 	u64				kcov_handle;
1432 
1433 	/* KCOV sequence number: */
1434 	int				kcov_sequence;
1435 
1436 	/* Collect coverage from softirq context: */
1437 	unsigned int			kcov_softirq;
1438 #endif
1439 
1440 #ifdef CONFIG_MEMCG
1441 	struct mem_cgroup		*memcg_in_oom;
1442 	gfp_t				memcg_oom_gfp_mask;
1443 	int				memcg_oom_order;
1444 
1445 	/* Number of pages to reclaim on returning to userland: */
1446 	unsigned int			memcg_nr_pages_over_high;
1447 
1448 	/* Used by memcontrol for targeted memcg charge: */
1449 	struct mem_cgroup		*active_memcg;
1450 #endif
1451 
1452 #ifdef CONFIG_BLK_CGROUP
1453 	struct gendisk			*throttle_disk;
1454 #endif
1455 
1456 #ifdef CONFIG_UPROBES
1457 	struct uprobe_task		*utask;
1458 #endif
1459 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1460 	unsigned int			sequential_io;
1461 	unsigned int			sequential_io_avg;
1462 #endif
1463 	struct kmap_ctrl		kmap_ctrl;
1464 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1465 	unsigned long			task_state_change;
1466 # ifdef CONFIG_PREEMPT_RT
1467 	unsigned long			saved_state_change;
1468 # endif
1469 #endif
1470 	struct rcu_head			rcu;
1471 	refcount_t			rcu_users;
1472 	int				pagefault_disabled;
1473 #ifdef CONFIG_MMU
1474 	struct task_struct		*oom_reaper_list;
1475 	struct timer_list		oom_reaper_timer;
1476 #endif
1477 #ifdef CONFIG_VMAP_STACK
1478 	struct vm_struct		*stack_vm_area;
1479 #endif
1480 #ifdef CONFIG_THREAD_INFO_IN_TASK
1481 	/* A live task holds one reference: */
1482 	refcount_t			stack_refcount;
1483 #endif
1484 #ifdef CONFIG_LIVEPATCH
1485 	int patch_state;
1486 #endif
1487 #ifdef CONFIG_SECURITY
1488 	/* Used by LSM modules for access restriction: */
1489 	void				*security;
1490 #endif
1491 #ifdef CONFIG_BPF_SYSCALL
1492 	/* Used by BPF task local storage */
1493 	struct bpf_local_storage __rcu	*bpf_storage;
1494 	/* Used for BPF run context */
1495 	struct bpf_run_ctx		*bpf_ctx;
1496 #endif
1497 
1498 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK
1499 	unsigned long			lowest_stack;
1500 	unsigned long			prev_lowest_stack;
1501 #endif
1502 
1503 #ifdef CONFIG_X86_MCE
1504 	void __user			*mce_vaddr;
1505 	__u64				mce_kflags;
1506 	u64				mce_addr;
1507 	__u64				mce_ripv : 1,
1508 					mce_whole_page : 1,
1509 					__mce_reserved : 62;
1510 	struct callback_head		mce_kill_me;
1511 	int				mce_count;
1512 #endif
1513 
1514 #ifdef CONFIG_KRETPROBES
1515 	struct llist_head               kretprobe_instances;
1516 #endif
1517 #ifdef CONFIG_RETHOOK
1518 	struct llist_head               rethooks;
1519 #endif
1520 
1521 #ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH
1522 	/*
1523 	 * If L1D flush is supported on mm context switch
1524 	 * then we use this callback head to queue kill work
1525 	 * to kill tasks that are not running on SMT disabled
1526 	 * cores
1527 	 */
1528 	struct callback_head		l1d_flush_kill;
1529 #endif
1530 
1531 #ifdef CONFIG_RV
1532 	/*
1533 	 * Per-task RV monitor. Nowadays fixed in RV_PER_TASK_MONITORS.
1534 	 * If we find justification for more monitors, we can think
1535 	 * about adding more or developing a dynamic method. So far,
1536 	 * none of these are justified.
1537 	 */
1538 	union rv_task_monitor		rv[RV_PER_TASK_MONITORS];
1539 #endif
1540 
1541 #ifdef CONFIG_USER_EVENTS
1542 	struct user_event_mm		*user_event_mm;
1543 #endif
1544 
1545 	/*
1546 	 * New fields for task_struct should be added above here, so that
1547 	 * they are included in the randomized portion of task_struct.
1548 	 */
1549 	randomized_struct_fields_end
1550 
1551 	/* CPU-specific state of this task: */
1552 	struct thread_struct		thread;
1553 
1554 	/*
1555 	 * WARNING: on x86, 'thread_struct' contains a variable-sized
1556 	 * structure.  It *MUST* be at the end of 'task_struct'.
1557 	 *
1558 	 * Do not put anything below here!
1559 	 */
1560 };
1561 
task_pid(struct task_struct * task)1562 static inline struct pid *task_pid(struct task_struct *task)
1563 {
1564 	return task->thread_pid;
1565 }
1566 
1567 /*
1568  * the helpers to get the task's different pids as they are seen
1569  * from various namespaces
1570  *
1571  * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1572  * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1573  *                     current.
1574  * task_xid_nr_ns()  : id seen from the ns specified;
1575  *
1576  * see also pid_nr() etc in include/linux/pid.h
1577  */
1578 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, struct pid_namespace *ns);
1579 
task_pid_nr(struct task_struct * tsk)1580 static inline pid_t task_pid_nr(struct task_struct *tsk)
1581 {
1582 	return tsk->pid;
1583 }
1584 
task_pid_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1585 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1586 {
1587 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1588 }
1589 
task_pid_vnr(struct task_struct * tsk)1590 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1591 {
1592 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1593 }
1594 
1595 
task_tgid_nr(struct task_struct * tsk)1596 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1597 {
1598 	return tsk->tgid;
1599 }
1600 
1601 /**
1602  * pid_alive - check that a task structure is not stale
1603  * @p: Task structure to be checked.
1604  *
1605  * Test if a process is not yet dead (at most zombie state)
1606  * If pid_alive fails, then pointers within the task structure
1607  * can be stale and must not be dereferenced.
1608  *
1609  * Return: 1 if the process is alive. 0 otherwise.
1610  */
pid_alive(const struct task_struct * p)1611 static inline int pid_alive(const struct task_struct *p)
1612 {
1613 	return p->thread_pid != NULL;
1614 }
1615 
task_pgrp_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1616 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1617 {
1618 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1619 }
1620 
task_pgrp_vnr(struct task_struct * tsk)1621 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1622 {
1623 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1624 }
1625 
1626 
task_session_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1627 static inline pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1628 {
1629 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1630 }
1631 
task_session_vnr(struct task_struct * tsk)1632 static inline pid_t task_session_vnr(struct task_struct *tsk)
1633 {
1634 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1635 }
1636 
task_tgid_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1637 static inline pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1638 {
1639 	return __task_pid_nr_ns(tsk, PIDTYPE_TGID, ns);
1640 }
1641 
task_tgid_vnr(struct task_struct * tsk)1642 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1643 {
1644 	return __task_pid_nr_ns(tsk, PIDTYPE_TGID, NULL);
1645 }
1646 
task_ppid_nr_ns(const struct task_struct * tsk,struct pid_namespace * ns)1647 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1648 {
1649 	pid_t pid = 0;
1650 
1651 	rcu_read_lock();
1652 	if (pid_alive(tsk))
1653 		pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1654 	rcu_read_unlock();
1655 
1656 	return pid;
1657 }
1658 
task_ppid_nr(const struct task_struct * tsk)1659 static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1660 {
1661 	return task_ppid_nr_ns(tsk, &init_pid_ns);
1662 }
1663 
1664 /* Obsolete, do not use: */
task_pgrp_nr(struct task_struct * tsk)1665 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1666 {
1667 	return task_pgrp_nr_ns(tsk, &init_pid_ns);
1668 }
1669 
1670 #define TASK_REPORT_IDLE	(TASK_REPORT + 1)
1671 #define TASK_REPORT_MAX		(TASK_REPORT_IDLE << 1)
1672 
__task_state_index(unsigned int tsk_state,unsigned int tsk_exit_state)1673 static inline unsigned int __task_state_index(unsigned int tsk_state,
1674 					      unsigned int tsk_exit_state)
1675 {
1676 	unsigned int state = (tsk_state | tsk_exit_state) & TASK_REPORT;
1677 
1678 	BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);
1679 
1680 	if ((tsk_state & TASK_IDLE) == TASK_IDLE)
1681 		state = TASK_REPORT_IDLE;
1682 
1683 	/*
1684 	 * We're lying here, but rather than expose a completely new task state
1685 	 * to userspace, we can make this appear as if the task has gone through
1686 	 * a regular rt_mutex_lock() call.
1687 	 * Report frozen tasks as uninterruptible.
1688 	 */
1689 	if ((tsk_state & TASK_RTLOCK_WAIT) || (tsk_state & TASK_FROZEN))
1690 		state = TASK_UNINTERRUPTIBLE;
1691 
1692 	return fls(state);
1693 }
1694 
task_state_index(struct task_struct * tsk)1695 static inline unsigned int task_state_index(struct task_struct *tsk)
1696 {
1697 	return __task_state_index(READ_ONCE(tsk->__state), tsk->exit_state);
1698 }
1699 
task_index_to_char(unsigned int state)1700 static inline char task_index_to_char(unsigned int state)
1701 {
1702 	static const char state_char[] = "RSDTtXZPI";
1703 
1704 	BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1);
1705 
1706 	return state_char[state];
1707 }
1708 
task_state_to_char(struct task_struct * tsk)1709 static inline char task_state_to_char(struct task_struct *tsk)
1710 {
1711 	return task_index_to_char(task_state_index(tsk));
1712 }
1713 
1714 /**
1715  * is_global_init - check if a task structure is init. Since init
1716  * is free to have sub-threads we need to check tgid.
1717  * @tsk: Task structure to be checked.
1718  *
1719  * Check if a task structure is the first user space task the kernel created.
1720  *
1721  * Return: 1 if the task structure is init. 0 otherwise.
1722  */
is_global_init(struct task_struct * tsk)1723 static inline int is_global_init(struct task_struct *tsk)
1724 {
1725 	return task_tgid_nr(tsk) == 1;
1726 }
1727 
1728 extern struct pid *cad_pid;
1729 
1730 /*
1731  * Per process flags
1732  */
1733 #define PF_VCPU			0x00000001	/* I'm a virtual CPU */
1734 #define PF_IDLE			0x00000002	/* I am an IDLE thread */
1735 #define PF_EXITING		0x00000004	/* Getting shut down */
1736 #define PF_POSTCOREDUMP		0x00000008	/* Coredumps should ignore this task */
1737 #define PF_IO_WORKER		0x00000010	/* Task is an IO worker */
1738 #define PF_WQ_WORKER		0x00000020	/* I'm a workqueue worker */
1739 #define PF_FORKNOEXEC		0x00000040	/* Forked but didn't exec */
1740 #define PF_MCE_PROCESS		0x00000080      /* Process policy on mce errors */
1741 #define PF_SUPERPRIV		0x00000100	/* Used super-user privileges */
1742 #define PF_DUMPCORE		0x00000200	/* Dumped core */
1743 #define PF_SIGNALED		0x00000400	/* Killed by a signal */
1744 #define PF_MEMALLOC		0x00000800	/* Allocating memory */
1745 #define PF_NPROC_EXCEEDED	0x00001000	/* set_user() noticed that RLIMIT_NPROC was exceeded */
1746 #define PF_USED_MATH		0x00002000	/* If unset the fpu must be initialized before use */
1747 #define PF_USER_WORKER		0x00004000	/* Kernel thread cloned from userspace thread */
1748 #define PF_NOFREEZE		0x00008000	/* This thread should not be frozen */
1749 #define PF__HOLE__00010000	0x00010000
1750 #define PF_KSWAPD		0x00020000	/* I am kswapd */
1751 #define PF_MEMALLOC_NOFS	0x00040000	/* All allocation requests will inherit GFP_NOFS */
1752 #define PF_MEMALLOC_NOIO	0x00080000	/* All allocation requests will inherit GFP_NOIO */
1753 #define PF_LOCAL_THROTTLE	0x00100000	/* Throttle writes only against the bdi I write to,
1754 						 * I am cleaning dirty pages from some other bdi. */
1755 #define PF_KTHREAD		0x00200000	/* I am a kernel thread */
1756 #define PF_RANDOMIZE		0x00400000	/* Randomize virtual address space */
1757 #define PF__HOLE__00800000	0x00800000
1758 #define PF__HOLE__01000000	0x01000000
1759 #define PF__HOLE__02000000	0x02000000
1760 #define PF_NO_SETAFFINITY	0x04000000	/* Userland is not allowed to meddle with cpus_mask */
1761 #define PF_MCE_EARLY		0x08000000      /* Early kill for mce process policy */
1762 #define PF_MEMALLOC_PIN		0x10000000	/* Allocation context constrained to zones which allow long term pinning. */
1763 #define PF__HOLE__20000000	0x20000000
1764 #define PF__HOLE__40000000	0x40000000
1765 #define PF_SUSPEND_TASK		0x80000000      /* This thread called freeze_processes() and should not be frozen */
1766 
1767 /*
1768  * Only the _current_ task can read/write to tsk->flags, but other
1769  * tasks can access tsk->flags in readonly mode for example
1770  * with tsk_used_math (like during threaded core dumping).
1771  * There is however an exception to this rule during ptrace
1772  * or during fork: the ptracer task is allowed to write to the
1773  * child->flags of its traced child (same goes for fork, the parent
1774  * can write to the child->flags), because we're guaranteed the
1775  * child is not running and in turn not changing child->flags
1776  * at the same time the parent does it.
1777  */
1778 #define clear_stopped_child_used_math(child)	do { (child)->flags &= ~PF_USED_MATH; } while (0)
1779 #define set_stopped_child_used_math(child)	do { (child)->flags |= PF_USED_MATH; } while (0)
1780 #define clear_used_math()			clear_stopped_child_used_math(current)
1781 #define set_used_math()				set_stopped_child_used_math(current)
1782 
1783 #define conditional_stopped_child_used_math(condition, child) \
1784 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1785 
1786 #define conditional_used_math(condition)	conditional_stopped_child_used_math(condition, current)
1787 
1788 #define copy_to_stopped_child_used_math(child) \
1789 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1790 
1791 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1792 #define tsk_used_math(p)			((p)->flags & PF_USED_MATH)
1793 #define used_math()				tsk_used_math(current)
1794 
is_percpu_thread(void)1795 static __always_inline bool is_percpu_thread(void)
1796 {
1797 #ifdef CONFIG_SMP
1798 	return (current->flags & PF_NO_SETAFFINITY) &&
1799 		(current->nr_cpus_allowed  == 1);
1800 #else
1801 	return true;
1802 #endif
1803 }
1804 
1805 /* Per-process atomic flags. */
1806 #define PFA_NO_NEW_PRIVS		0	/* May not gain new privileges. */
1807 #define PFA_SPREAD_PAGE			1	/* Spread page cache over cpuset */
1808 #define PFA_SPREAD_SLAB			2	/* Spread some slab caches over cpuset */
1809 #define PFA_SPEC_SSB_DISABLE		3	/* Speculative Store Bypass disabled */
1810 #define PFA_SPEC_SSB_FORCE_DISABLE	4	/* Speculative Store Bypass force disabled*/
1811 #define PFA_SPEC_IB_DISABLE		5	/* Indirect branch speculation restricted */
1812 #define PFA_SPEC_IB_FORCE_DISABLE	6	/* Indirect branch speculation permanently restricted */
1813 #define PFA_SPEC_SSB_NOEXEC		7	/* Speculative Store Bypass clear on execve() */
1814 
1815 #define TASK_PFA_TEST(name, func)					\
1816 	static inline bool task_##func(struct task_struct *p)		\
1817 	{ return test_bit(PFA_##name, &p->atomic_flags); }
1818 
1819 #define TASK_PFA_SET(name, func)					\
1820 	static inline void task_set_##func(struct task_struct *p)	\
1821 	{ set_bit(PFA_##name, &p->atomic_flags); }
1822 
1823 #define TASK_PFA_CLEAR(name, func)					\
1824 	static inline void task_clear_##func(struct task_struct *p)	\
1825 	{ clear_bit(PFA_##name, &p->atomic_flags); }
1826 
TASK_PFA_TEST(NO_NEW_PRIVS,no_new_privs)1827 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1828 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1829 
1830 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1831 TASK_PFA_SET(SPREAD_PAGE, spread_page)
1832 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
1833 
1834 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
1835 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
1836 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1837 
1838 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable)
1839 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable)
1840 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable)
1841 
1842 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1843 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1844 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1845 
1846 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1847 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1848 
1849 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable)
1850 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable)
1851 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable)
1852 
1853 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1854 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1855 
1856 static inline void
1857 current_restore_flags(unsigned long orig_flags, unsigned long flags)
1858 {
1859 	current->flags &= ~flags;
1860 	current->flags |= orig_flags & flags;
1861 }
1862 
1863 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
1864 extern int task_can_attach(struct task_struct *p);
1865 extern int dl_bw_alloc(int cpu, u64 dl_bw);
1866 extern void dl_bw_free(int cpu, u64 dl_bw);
1867 #ifdef CONFIG_SMP
1868 
1869 /* do_set_cpus_allowed() - consider using set_cpus_allowed_ptr() instead */
1870 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask);
1871 
1872 /**
1873  * set_cpus_allowed_ptr - set CPU affinity mask of a task
1874  * @p: the task
1875  * @new_mask: CPU affinity mask
1876  *
1877  * Return: zero if successful, or a negative error code
1878  */
1879 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
1880 extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node);
1881 extern void release_user_cpus_ptr(struct task_struct *p);
1882 extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask);
1883 extern void force_compatible_cpus_allowed_ptr(struct task_struct *p);
1884 extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p);
1885 #else
do_set_cpus_allowed(struct task_struct * p,const struct cpumask * new_mask)1886 static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
1887 {
1888 }
set_cpus_allowed_ptr(struct task_struct * p,const struct cpumask * new_mask)1889 static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
1890 {
1891 	if (!cpumask_test_cpu(0, new_mask))
1892 		return -EINVAL;
1893 	return 0;
1894 }
dup_user_cpus_ptr(struct task_struct * dst,struct task_struct * src,int node)1895 static inline int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node)
1896 {
1897 	if (src->user_cpus_ptr)
1898 		return -EINVAL;
1899 	return 0;
1900 }
release_user_cpus_ptr(struct task_struct * p)1901 static inline void release_user_cpus_ptr(struct task_struct *p)
1902 {
1903 	WARN_ON(p->user_cpus_ptr);
1904 }
1905 
dl_task_check_affinity(struct task_struct * p,const struct cpumask * mask)1906 static inline int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask)
1907 {
1908 	return 0;
1909 }
1910 #endif
1911 
1912 extern int yield_to(struct task_struct *p, bool preempt);
1913 extern void set_user_nice(struct task_struct *p, long nice);
1914 extern int task_prio(const struct task_struct *p);
1915 
1916 /**
1917  * task_nice - return the nice value of a given task.
1918  * @p: the task in question.
1919  *
1920  * Return: The nice value [ -20 ... 0 ... 19 ].
1921  */
task_nice(const struct task_struct * p)1922 static inline int task_nice(const struct task_struct *p)
1923 {
1924 	return PRIO_TO_NICE((p)->static_prio);
1925 }
1926 
1927 extern int can_nice(const struct task_struct *p, const int nice);
1928 extern int task_curr(const struct task_struct *p);
1929 extern int idle_cpu(int cpu);
1930 extern int available_idle_cpu(int cpu);
1931 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
1932 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
1933 extern void sched_set_fifo(struct task_struct *p);
1934 extern void sched_set_fifo_low(struct task_struct *p);
1935 extern void sched_set_normal(struct task_struct *p, int nice);
1936 extern int sched_setattr(struct task_struct *, const struct sched_attr *);
1937 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *);
1938 extern struct task_struct *idle_task(int cpu);
1939 
1940 /**
1941  * is_idle_task - is the specified task an idle task?
1942  * @p: the task in question.
1943  *
1944  * Return: 1 if @p is an idle task. 0 otherwise.
1945  */
is_idle_task(const struct task_struct * p)1946 static __always_inline bool is_idle_task(const struct task_struct *p)
1947 {
1948 	return !!(p->flags & PF_IDLE);
1949 }
1950 
1951 extern struct task_struct *curr_task(int cpu);
1952 extern void ia64_set_curr_task(int cpu, struct task_struct *p);
1953 
1954 void yield(void);
1955 
1956 union thread_union {
1957 #ifndef CONFIG_ARCH_TASK_STRUCT_ON_STACK
1958 	struct task_struct task;
1959 #endif
1960 #ifndef CONFIG_THREAD_INFO_IN_TASK
1961 	struct thread_info thread_info;
1962 #endif
1963 	unsigned long stack[THREAD_SIZE/sizeof(long)];
1964 };
1965 
1966 #ifndef CONFIG_THREAD_INFO_IN_TASK
1967 extern struct thread_info init_thread_info;
1968 #endif
1969 
1970 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];
1971 
1972 #ifdef CONFIG_THREAD_INFO_IN_TASK
1973 # define task_thread_info(task)	(&(task)->thread_info)
1974 #elif !defined(__HAVE_THREAD_FUNCTIONS)
1975 # define task_thread_info(task)	((struct thread_info *)(task)->stack)
1976 #endif
1977 
1978 /*
1979  * find a task by one of its numerical ids
1980  *
1981  * find_task_by_pid_ns():
1982  *      finds a task by its pid in the specified namespace
1983  * find_task_by_vpid():
1984  *      finds a task by its virtual pid
1985  *
1986  * see also find_vpid() etc in include/linux/pid.h
1987  */
1988 
1989 extern struct task_struct *find_task_by_vpid(pid_t nr);
1990 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns);
1991 
1992 /*
1993  * find a task by its virtual pid and get the task struct
1994  */
1995 extern struct task_struct *find_get_task_by_vpid(pid_t nr);
1996 
1997 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1998 extern int wake_up_process(struct task_struct *tsk);
1999 extern void wake_up_new_task(struct task_struct *tsk);
2000 
2001 #ifdef CONFIG_SMP
2002 extern void kick_process(struct task_struct *tsk);
2003 #else
kick_process(struct task_struct * tsk)2004 static inline void kick_process(struct task_struct *tsk) { }
2005 #endif
2006 
2007 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
2008 
set_task_comm(struct task_struct * tsk,const char * from)2009 static inline void set_task_comm(struct task_struct *tsk, const char *from)
2010 {
2011 	__set_task_comm(tsk, from, false);
2012 }
2013 
2014 extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk);
2015 #define get_task_comm(buf, tsk) ({			\
2016 	BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN);	\
2017 	__get_task_comm(buf, sizeof(buf), tsk);		\
2018 })
2019 
2020 #ifdef CONFIG_SMP
scheduler_ipi(void)2021 static __always_inline void scheduler_ipi(void)
2022 {
2023 	/*
2024 	 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting
2025 	 * TIF_NEED_RESCHED remotely (for the first time) will also send
2026 	 * this IPI.
2027 	 */
2028 	preempt_fold_need_resched();
2029 }
2030 #else
scheduler_ipi(void)2031 static inline void scheduler_ipi(void) { }
2032 #endif
2033 
2034 extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state);
2035 
2036 /*
2037  * Set thread flags in other task's structures.
2038  * See asm/thread_info.h for TIF_xxxx flags available:
2039  */
set_tsk_thread_flag(struct task_struct * tsk,int flag)2040 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2041 {
2042 	set_ti_thread_flag(task_thread_info(tsk), flag);
2043 }
2044 
clear_tsk_thread_flag(struct task_struct * tsk,int flag)2045 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2046 {
2047 	clear_ti_thread_flag(task_thread_info(tsk), flag);
2048 }
2049 
update_tsk_thread_flag(struct task_struct * tsk,int flag,bool value)2050 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag,
2051 					  bool value)
2052 {
2053 	update_ti_thread_flag(task_thread_info(tsk), flag, value);
2054 }
2055 
test_and_set_tsk_thread_flag(struct task_struct * tsk,int flag)2056 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2057 {
2058 	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2059 }
2060 
test_and_clear_tsk_thread_flag(struct task_struct * tsk,int flag)2061 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2062 {
2063 	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2064 }
2065 
test_tsk_thread_flag(struct task_struct * tsk,int flag)2066 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2067 {
2068 	return test_ti_thread_flag(task_thread_info(tsk), flag);
2069 }
2070 
set_tsk_need_resched(struct task_struct * tsk)2071 static inline void set_tsk_need_resched(struct task_struct *tsk)
2072 {
2073 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2074 }
2075 
clear_tsk_need_resched(struct task_struct * tsk)2076 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2077 {
2078 	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2079 }
2080 
test_tsk_need_resched(struct task_struct * tsk)2081 static inline int test_tsk_need_resched(struct task_struct *tsk)
2082 {
2083 	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2084 }
2085 
2086 /*
2087  * cond_resched() and cond_resched_lock(): latency reduction via
2088  * explicit rescheduling in places that are safe. The return
2089  * value indicates whether a reschedule was done in fact.
2090  * cond_resched_lock() will drop the spinlock before scheduling,
2091  */
2092 #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC)
2093 extern int __cond_resched(void);
2094 
2095 #if defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL)
2096 
2097 void sched_dynamic_klp_enable(void);
2098 void sched_dynamic_klp_disable(void);
2099 
2100 DECLARE_STATIC_CALL(cond_resched, __cond_resched);
2101 
_cond_resched(void)2102 static __always_inline int _cond_resched(void)
2103 {
2104 	return static_call_mod(cond_resched)();
2105 }
2106 
2107 #elif defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY)
2108 
2109 extern int dynamic_cond_resched(void);
2110 
_cond_resched(void)2111 static __always_inline int _cond_resched(void)
2112 {
2113 	return dynamic_cond_resched();
2114 }
2115 
2116 #else /* !CONFIG_PREEMPTION */
2117 
_cond_resched(void)2118 static inline int _cond_resched(void)
2119 {
2120 	klp_sched_try_switch();
2121 	return __cond_resched();
2122 }
2123 
2124 #endif /* PREEMPT_DYNAMIC && CONFIG_HAVE_PREEMPT_DYNAMIC_CALL */
2125 
2126 #else /* CONFIG_PREEMPTION && !CONFIG_PREEMPT_DYNAMIC */
2127 
_cond_resched(void)2128 static inline int _cond_resched(void)
2129 {
2130 	klp_sched_try_switch();
2131 	return 0;
2132 }
2133 
2134 #endif /* !CONFIG_PREEMPTION || CONFIG_PREEMPT_DYNAMIC */
2135 
2136 #define cond_resched() ({			\
2137 	__might_resched(__FILE__, __LINE__, 0);	\
2138 	_cond_resched();			\
2139 })
2140 
2141 extern int __cond_resched_lock(spinlock_t *lock);
2142 extern int __cond_resched_rwlock_read(rwlock_t *lock);
2143 extern int __cond_resched_rwlock_write(rwlock_t *lock);
2144 
2145 #define MIGHT_RESCHED_RCU_SHIFT		8
2146 #define MIGHT_RESCHED_PREEMPT_MASK	((1U << MIGHT_RESCHED_RCU_SHIFT) - 1)
2147 
2148 #ifndef CONFIG_PREEMPT_RT
2149 /*
2150  * Non RT kernels have an elevated preempt count due to the held lock,
2151  * but are not allowed to be inside a RCU read side critical section
2152  */
2153 # define PREEMPT_LOCK_RESCHED_OFFSETS	PREEMPT_LOCK_OFFSET
2154 #else
2155 /*
2156  * spin/rw_lock() on RT implies rcu_read_lock(). The might_sleep() check in
2157  * cond_resched*lock() has to take that into account because it checks for
2158  * preempt_count() and rcu_preempt_depth().
2159  */
2160 # define PREEMPT_LOCK_RESCHED_OFFSETS	\
2161 	(PREEMPT_LOCK_OFFSET + (1U << MIGHT_RESCHED_RCU_SHIFT))
2162 #endif
2163 
2164 #define cond_resched_lock(lock) ({						\
2165 	__might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS);	\
2166 	__cond_resched_lock(lock);						\
2167 })
2168 
2169 #define cond_resched_rwlock_read(lock) ({					\
2170 	__might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS);	\
2171 	__cond_resched_rwlock_read(lock);					\
2172 })
2173 
2174 #define cond_resched_rwlock_write(lock) ({					\
2175 	__might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS);	\
2176 	__cond_resched_rwlock_write(lock);					\
2177 })
2178 
cond_resched_rcu(void)2179 static inline void cond_resched_rcu(void)
2180 {
2181 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
2182 	rcu_read_unlock();
2183 	cond_resched();
2184 	rcu_read_lock();
2185 #endif
2186 }
2187 
2188 #ifdef CONFIG_PREEMPT_DYNAMIC
2189 
2190 extern bool preempt_model_none(void);
2191 extern bool preempt_model_voluntary(void);
2192 extern bool preempt_model_full(void);
2193 
2194 #else
2195 
preempt_model_none(void)2196 static inline bool preempt_model_none(void)
2197 {
2198 	return IS_ENABLED(CONFIG_PREEMPT_NONE);
2199 }
preempt_model_voluntary(void)2200 static inline bool preempt_model_voluntary(void)
2201 {
2202 	return IS_ENABLED(CONFIG_PREEMPT_VOLUNTARY);
2203 }
preempt_model_full(void)2204 static inline bool preempt_model_full(void)
2205 {
2206 	return IS_ENABLED(CONFIG_PREEMPT);
2207 }
2208 
2209 #endif
2210 
preempt_model_rt(void)2211 static inline bool preempt_model_rt(void)
2212 {
2213 	return IS_ENABLED(CONFIG_PREEMPT_RT);
2214 }
2215 
2216 /*
2217  * Does the preemption model allow non-cooperative preemption?
2218  *
2219  * For !CONFIG_PREEMPT_DYNAMIC kernels this is an exact match with
2220  * CONFIG_PREEMPTION; for CONFIG_PREEMPT_DYNAMIC this doesn't work as the
2221  * kernel is *built* with CONFIG_PREEMPTION=y but may run with e.g. the
2222  * PREEMPT_NONE model.
2223  */
preempt_model_preemptible(void)2224 static inline bool preempt_model_preemptible(void)
2225 {
2226 	return preempt_model_full() || preempt_model_rt();
2227 }
2228 
2229 /*
2230  * Does a critical section need to be broken due to another
2231  * task waiting?: (technically does not depend on CONFIG_PREEMPTION,
2232  * but a general need for low latency)
2233  */
spin_needbreak(spinlock_t * lock)2234 static inline int spin_needbreak(spinlock_t *lock)
2235 {
2236 #ifdef CONFIG_PREEMPTION
2237 	return spin_is_contended(lock);
2238 #else
2239 	return 0;
2240 #endif
2241 }
2242 
2243 /*
2244  * Check if a rwlock is contended.
2245  * Returns non-zero if there is another task waiting on the rwlock.
2246  * Returns zero if the lock is not contended or the system / underlying
2247  * rwlock implementation does not support contention detection.
2248  * Technically does not depend on CONFIG_PREEMPTION, but a general need
2249  * for low latency.
2250  */
rwlock_needbreak(rwlock_t * lock)2251 static inline int rwlock_needbreak(rwlock_t *lock)
2252 {
2253 #ifdef CONFIG_PREEMPTION
2254 	return rwlock_is_contended(lock);
2255 #else
2256 	return 0;
2257 #endif
2258 }
2259 
need_resched(void)2260 static __always_inline bool need_resched(void)
2261 {
2262 	return unlikely(tif_need_resched());
2263 }
2264 
2265 /*
2266  * Wrappers for p->thread_info->cpu access. No-op on UP.
2267  */
2268 #ifdef CONFIG_SMP
2269 
task_cpu(const struct task_struct * p)2270 static inline unsigned int task_cpu(const struct task_struct *p)
2271 {
2272 	return READ_ONCE(task_thread_info(p)->cpu);
2273 }
2274 
2275 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2276 
2277 #else
2278 
task_cpu(const struct task_struct * p)2279 static inline unsigned int task_cpu(const struct task_struct *p)
2280 {
2281 	return 0;
2282 }
2283 
set_task_cpu(struct task_struct * p,unsigned int cpu)2284 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2285 {
2286 }
2287 
2288 #endif /* CONFIG_SMP */
2289 
2290 extern bool sched_task_on_rq(struct task_struct *p);
2291 extern unsigned long get_wchan(struct task_struct *p);
2292 extern struct task_struct *cpu_curr_snapshot(int cpu);
2293 
2294 /*
2295  * In order to reduce various lock holder preemption latencies provide an
2296  * interface to see if a vCPU is currently running or not.
2297  *
2298  * This allows us to terminate optimistic spin loops and block, analogous to
2299  * the native optimistic spin heuristic of testing if the lock owner task is
2300  * running or not.
2301  */
2302 #ifndef vcpu_is_preempted
vcpu_is_preempted(int cpu)2303 static inline bool vcpu_is_preempted(int cpu)
2304 {
2305 	return false;
2306 }
2307 #endif
2308 
2309 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2310 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2311 
2312 #ifndef TASK_SIZE_OF
2313 #define TASK_SIZE_OF(tsk)	TASK_SIZE
2314 #endif
2315 
2316 #ifdef CONFIG_SMP
owner_on_cpu(struct task_struct * owner)2317 static inline bool owner_on_cpu(struct task_struct *owner)
2318 {
2319 	/*
2320 	 * As lock holder preemption issue, we both skip spinning if
2321 	 * task is not on cpu or its cpu is preempted
2322 	 */
2323 	return READ_ONCE(owner->on_cpu) && !vcpu_is_preempted(task_cpu(owner));
2324 }
2325 
2326 /* Returns effective CPU energy utilization, as seen by the scheduler */
2327 unsigned long sched_cpu_util(int cpu);
2328 #endif /* CONFIG_SMP */
2329 
2330 #ifdef CONFIG_RSEQ
2331 
2332 /*
2333  * Map the event mask on the user-space ABI enum rseq_cs_flags
2334  * for direct mask checks.
2335  */
2336 enum rseq_event_mask_bits {
2337 	RSEQ_EVENT_PREEMPT_BIT	= RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT,
2338 	RSEQ_EVENT_SIGNAL_BIT	= RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT,
2339 	RSEQ_EVENT_MIGRATE_BIT	= RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT,
2340 };
2341 
2342 enum rseq_event_mask {
2343 	RSEQ_EVENT_PREEMPT	= (1U << RSEQ_EVENT_PREEMPT_BIT),
2344 	RSEQ_EVENT_SIGNAL	= (1U << RSEQ_EVENT_SIGNAL_BIT),
2345 	RSEQ_EVENT_MIGRATE	= (1U << RSEQ_EVENT_MIGRATE_BIT),
2346 };
2347 
rseq_set_notify_resume(struct task_struct * t)2348 static inline void rseq_set_notify_resume(struct task_struct *t)
2349 {
2350 	if (t->rseq)
2351 		set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
2352 }
2353 
2354 void __rseq_handle_notify_resume(struct ksignal *sig, struct pt_regs *regs);
2355 
rseq_handle_notify_resume(struct ksignal * ksig,struct pt_regs * regs)2356 static inline void rseq_handle_notify_resume(struct ksignal *ksig,
2357 					     struct pt_regs *regs)
2358 {
2359 	if (current->rseq)
2360 		__rseq_handle_notify_resume(ksig, regs);
2361 }
2362 
rseq_signal_deliver(struct ksignal * ksig,struct pt_regs * regs)2363 static inline void rseq_signal_deliver(struct ksignal *ksig,
2364 				       struct pt_regs *regs)
2365 {
2366 	preempt_disable();
2367 	__set_bit(RSEQ_EVENT_SIGNAL_BIT, &current->rseq_event_mask);
2368 	preempt_enable();
2369 	rseq_handle_notify_resume(ksig, regs);
2370 }
2371 
2372 /* rseq_preempt() requires preemption to be disabled. */
rseq_preempt(struct task_struct * t)2373 static inline void rseq_preempt(struct task_struct *t)
2374 {
2375 	__set_bit(RSEQ_EVENT_PREEMPT_BIT, &t->rseq_event_mask);
2376 	rseq_set_notify_resume(t);
2377 }
2378 
2379 /* rseq_migrate() requires preemption to be disabled. */
rseq_migrate(struct task_struct * t)2380 static inline void rseq_migrate(struct task_struct *t)
2381 {
2382 	__set_bit(RSEQ_EVENT_MIGRATE_BIT, &t->rseq_event_mask);
2383 	rseq_set_notify_resume(t);
2384 }
2385 
2386 /*
2387  * If parent process has a registered restartable sequences area, the
2388  * child inherits. Unregister rseq for a clone with CLONE_VM set.
2389  */
rseq_fork(struct task_struct * t,unsigned long clone_flags)2390 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
2391 {
2392 	if (clone_flags & CLONE_VM) {
2393 		t->rseq = NULL;
2394 		t->rseq_len = 0;
2395 		t->rseq_sig = 0;
2396 		t->rseq_event_mask = 0;
2397 	} else {
2398 		t->rseq = current->rseq;
2399 		t->rseq_len = current->rseq_len;
2400 		t->rseq_sig = current->rseq_sig;
2401 		t->rseq_event_mask = current->rseq_event_mask;
2402 	}
2403 }
2404 
rseq_execve(struct task_struct * t)2405 static inline void rseq_execve(struct task_struct *t)
2406 {
2407 	t->rseq = NULL;
2408 	t->rseq_len = 0;
2409 	t->rseq_sig = 0;
2410 	t->rseq_event_mask = 0;
2411 }
2412 
2413 #else
2414 
rseq_set_notify_resume(struct task_struct * t)2415 static inline void rseq_set_notify_resume(struct task_struct *t)
2416 {
2417 }
rseq_handle_notify_resume(struct ksignal * ksig,struct pt_regs * regs)2418 static inline void rseq_handle_notify_resume(struct ksignal *ksig,
2419 					     struct pt_regs *regs)
2420 {
2421 }
rseq_signal_deliver(struct ksignal * ksig,struct pt_regs * regs)2422 static inline void rseq_signal_deliver(struct ksignal *ksig,
2423 				       struct pt_regs *regs)
2424 {
2425 }
rseq_preempt(struct task_struct * t)2426 static inline void rseq_preempt(struct task_struct *t)
2427 {
2428 }
rseq_migrate(struct task_struct * t)2429 static inline void rseq_migrate(struct task_struct *t)
2430 {
2431 }
rseq_fork(struct task_struct * t,unsigned long clone_flags)2432 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
2433 {
2434 }
rseq_execve(struct task_struct * t)2435 static inline void rseq_execve(struct task_struct *t)
2436 {
2437 }
2438 
2439 #endif
2440 
2441 #ifdef CONFIG_DEBUG_RSEQ
2442 
2443 void rseq_syscall(struct pt_regs *regs);
2444 
2445 #else
2446 
rseq_syscall(struct pt_regs * regs)2447 static inline void rseq_syscall(struct pt_regs *regs)
2448 {
2449 }
2450 
2451 #endif
2452 
2453 #ifdef CONFIG_SCHED_CORE
2454 extern void sched_core_free(struct task_struct *tsk);
2455 extern void sched_core_fork(struct task_struct *p);
2456 extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type,
2457 				unsigned long uaddr);
2458 extern int sched_core_idle_cpu(int cpu);
2459 #else
sched_core_free(struct task_struct * tsk)2460 static inline void sched_core_free(struct task_struct *tsk) { }
sched_core_fork(struct task_struct * p)2461 static inline void sched_core_fork(struct task_struct *p) { }
sched_core_idle_cpu(int cpu)2462 static inline int sched_core_idle_cpu(int cpu) { return idle_cpu(cpu); }
2463 #endif
2464 
2465 extern void sched_set_stop_task(int cpu, struct task_struct *stop);
2466 
2467 #endif
2468