xref: /linux/include/linux/sched.h (revision 136114e0abf03005e182d75761ab694648e6d388)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_SCHED_H
3 #define _LINUX_SCHED_H
4 
5 /*
6  * Define 'struct task_struct' and provide the main scheduler
7  * APIs (schedule(), wakeup variants, etc.)
8  */
9 
10 #include <uapi/linux/sched.h>
11 
12 #include <asm/current.h>
13 #include <asm/processor.h>
14 #include <linux/thread_info.h>
15 #include <linux/preempt.h>
16 #include <linux/cpumask_types.h>
17 
18 #include <linux/cache.h>
19 #include <linux/irqflags_types.h>
20 #include <linux/smp_types.h>
21 #include <linux/pid_types.h>
22 #include <linux/sem_types.h>
23 #include <linux/shm.h>
24 #include <linux/kmsan_types.h>
25 #include <linux/mutex_types.h>
26 #include <linux/plist_types.h>
27 #include <linux/hrtimer_types.h>
28 #include <linux/timer_types.h>
29 #include <linux/seccomp_types.h>
30 #include <linux/nodemask_types.h>
31 #include <linux/refcount_types.h>
32 #include <linux/resource.h>
33 #include <linux/latencytop.h>
34 #include <linux/sched/prio.h>
35 #include <linux/sched/types.h>
36 #include <linux/signal_types.h>
37 #include <linux/spinlock.h>
38 #include <linux/syscall_user_dispatch_types.h>
39 #include <linux/mm_types_task.h>
40 #include <linux/netdevice_xmit.h>
41 #include <linux/task_io_accounting.h>
42 #include <linux/posix-timers_types.h>
43 #include <linux/restart_block.h>
44 #include <linux/rseq_types.h>
45 #include <linux/seqlock_types.h>
46 #include <linux/kcsan.h>
47 #include <linux/rv.h>
48 #include <linux/uidgid_types.h>
49 #include <linux/tracepoint-defs.h>
50 #include <linux/unwind_deferred_types.h>
51 #include <asm/kmap_size.h>
52 #include <linux/time64.h>
53 #ifndef COMPILE_OFFSETS
54 #include <generated/rq-offsets.h>
55 #endif
56 
57 /* task_struct member predeclarations (sorted alphabetically): */
58 struct audit_context;
59 struct bio_list;
60 struct blk_plug;
61 struct bpf_local_storage;
62 struct bpf_run_ctx;
63 struct bpf_net_context;
64 struct capture_control;
65 struct cfs_rq;
66 struct fs_struct;
67 struct futex_pi_state;
68 struct io_context;
69 struct io_uring_task;
70 struct mempolicy;
71 struct nameidata;
72 struct nsproxy;
73 struct perf_event_context;
74 struct perf_ctx_data;
75 struct pid_namespace;
76 struct pipe_inode_info;
77 struct rcu_node;
78 struct reclaim_state;
79 struct robust_list_head;
80 struct root_domain;
81 struct rq;
82 struct sched_attr;
83 struct sched_dl_entity;
84 struct seq_file;
85 struct sighand_struct;
86 struct signal_struct;
87 struct task_delay_info;
88 struct task_group;
89 struct task_struct;
90 struct timespec64;
91 struct user_event_mm;
92 
93 #include <linux/sched/ext.h>
94 
95 /*
96  * Task state bitmask. NOTE! These bits are also
97  * encoded in fs/proc/array.c: get_task_state().
98  *
99  * We have two separate sets of flags: task->__state
100  * is about runnability, while task->exit_state are
101  * about the task exiting. Confusing, but this way
102  * modifying one set can't modify the other one by
103  * mistake.
104  */
105 
106 /* Used in tsk->__state: */
107 #define TASK_RUNNING			0x00000000
108 #define TASK_INTERRUPTIBLE		0x00000001
109 #define TASK_UNINTERRUPTIBLE		0x00000002
110 #define __TASK_STOPPED			0x00000004
111 #define __TASK_TRACED			0x00000008
112 /* Used in tsk->exit_state: */
113 #define EXIT_DEAD			0x00000010
114 #define EXIT_ZOMBIE			0x00000020
115 #define EXIT_TRACE			(EXIT_ZOMBIE | EXIT_DEAD)
116 /* Used in tsk->__state again: */
117 #define TASK_PARKED			0x00000040
118 #define TASK_DEAD			0x00000080
119 #define TASK_WAKEKILL			0x00000100
120 #define TASK_WAKING			0x00000200
121 #define TASK_NOLOAD			0x00000400
122 #define TASK_NEW			0x00000800
123 #define TASK_RTLOCK_WAIT		0x00001000
124 #define TASK_FREEZABLE			0x00002000
125 #define __TASK_FREEZABLE_UNSAFE	       (0x00004000 * IS_ENABLED(CONFIG_LOCKDEP))
126 #define TASK_FROZEN			0x00008000
127 #define TASK_STATE_MAX			0x00010000
128 
129 #define TASK_ANY			(TASK_STATE_MAX-1)
130 
131 /*
132  * DO NOT ADD ANY NEW USERS !
133  */
134 #define TASK_FREEZABLE_UNSAFE		(TASK_FREEZABLE | __TASK_FREEZABLE_UNSAFE)
135 
136 /* Convenience macros for the sake of set_current_state: */
137 #define TASK_KILLABLE			(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
138 #define TASK_STOPPED			(TASK_WAKEKILL | __TASK_STOPPED)
139 #define TASK_TRACED			__TASK_TRACED
140 
141 #define TASK_IDLE			(TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
142 
143 /* Convenience macros for the sake of wake_up(): */
144 #define TASK_NORMAL			(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
145 
146 /* get_task_state(): */
147 #define TASK_REPORT			(TASK_RUNNING | TASK_INTERRUPTIBLE | \
148 					 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
149 					 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \
150 					 TASK_PARKED)
151 
152 #define task_is_running(task)		(READ_ONCE((task)->__state) == TASK_RUNNING)
153 
154 #define task_is_traced(task)		((READ_ONCE(task->jobctl) & JOBCTL_TRACED) != 0)
155 #define task_is_stopped(task)		((READ_ONCE(task->jobctl) & JOBCTL_STOPPED) != 0)
156 #define task_is_stopped_or_traced(task)	((READ_ONCE(task->jobctl) & (JOBCTL_STOPPED | JOBCTL_TRACED)) != 0)
157 
158 /*
159  * Special states are those that do not use the normal wait-loop pattern. See
160  * the comment with set_special_state().
161  */
162 #define is_special_task_state(state)					\
163 	((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED |	\
164 		    TASK_DEAD | TASK_FROZEN))
165 
166 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
167 # define debug_normal_state_change(state_value)				\
168 	do {								\
169 		WARN_ON_ONCE(is_special_task_state(state_value));	\
170 		current->task_state_change = _THIS_IP_;			\
171 	} while (0)
172 
173 # define debug_special_state_change(state_value)			\
174 	do {								\
175 		WARN_ON_ONCE(!is_special_task_state(state_value));	\
176 		current->task_state_change = _THIS_IP_;			\
177 	} while (0)
178 
179 # define debug_rtlock_wait_set_state()					\
180 	do {								 \
181 		current->saved_state_change = current->task_state_change;\
182 		current->task_state_change = _THIS_IP_;			 \
183 	} while (0)
184 
185 # define debug_rtlock_wait_restore_state()				\
186 	do {								 \
187 		current->task_state_change = current->saved_state_change;\
188 	} while (0)
189 
190 #else
191 # define debug_normal_state_change(cond)	do { } while (0)
192 # define debug_special_state_change(cond)	do { } while (0)
193 # define debug_rtlock_wait_set_state()		do { } while (0)
194 # define debug_rtlock_wait_restore_state()	do { } while (0)
195 #endif
196 
197 #define trace_set_current_state(state_value)                     \
198 	do {                                                     \
199 		if (tracepoint_enabled(sched_set_state_tp))      \
200 			__trace_set_current_state(state_value); \
201 	} while (0)
202 
203 /*
204  * set_current_state() includes a barrier so that the write of current->__state
205  * is correctly serialised wrt the caller's subsequent test of whether to
206  * actually sleep:
207  *
208  *   for (;;) {
209  *	set_current_state(TASK_UNINTERRUPTIBLE);
210  *	if (CONDITION)
211  *	   break;
212  *
213  *	schedule();
214  *   }
215  *   __set_current_state(TASK_RUNNING);
216  *
217  * If the caller does not need such serialisation (because, for instance, the
218  * CONDITION test and condition change and wakeup are under the same lock) then
219  * use __set_current_state().
220  *
221  * The above is typically ordered against the wakeup, which does:
222  *
223  *   CONDITION = 1;
224  *   wake_up_state(p, TASK_UNINTERRUPTIBLE);
225  *
226  * where wake_up_state()/try_to_wake_up() executes a full memory barrier before
227  * accessing p->__state.
228  *
229  * Wakeup will do: if (@state & p->__state) p->__state = TASK_RUNNING, that is,
230  * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a
231  * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING).
232  *
233  * However, with slightly different timing the wakeup TASK_RUNNING store can
234  * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not
235  * a problem either because that will result in one extra go around the loop
236  * and our @cond test will save the day.
237  *
238  * Also see the comments of try_to_wake_up().
239  */
240 #define __set_current_state(state_value)				\
241 	do {								\
242 		debug_normal_state_change((state_value));		\
243 		trace_set_current_state(state_value);			\
244 		WRITE_ONCE(current->__state, (state_value));		\
245 	} while (0)
246 
247 #define set_current_state(state_value)					\
248 	do {								\
249 		debug_normal_state_change((state_value));		\
250 		trace_set_current_state(state_value);			\
251 		smp_store_mb(current->__state, (state_value));		\
252 	} while (0)
253 
254 /*
255  * set_special_state() should be used for those states when the blocking task
256  * can not use the regular condition based wait-loop. In that case we must
257  * serialize against wakeups such that any possible in-flight TASK_RUNNING
258  * stores will not collide with our state change.
259  */
260 #define set_special_state(state_value)					\
261 	do {								\
262 		unsigned long flags; /* may shadow */			\
263 									\
264 		raw_spin_lock_irqsave(&current->pi_lock, flags);	\
265 		debug_special_state_change((state_value));		\
266 		trace_set_current_state(state_value);			\
267 		WRITE_ONCE(current->__state, (state_value));		\
268 		raw_spin_unlock_irqrestore(&current->pi_lock, flags);	\
269 	} while (0)
270 
271 /*
272  * PREEMPT_RT specific variants for "sleeping" spin/rwlocks
273  *
274  * RT's spin/rwlock substitutions are state preserving. The state of the
275  * task when blocking on the lock is saved in task_struct::saved_state and
276  * restored after the lock has been acquired.  These operations are
277  * serialized by task_struct::pi_lock against try_to_wake_up(). Any non RT
278  * lock related wakeups while the task is blocked on the lock are
279  * redirected to operate on task_struct::saved_state to ensure that these
280  * are not dropped. On restore task_struct::saved_state is set to
281  * TASK_RUNNING so any wakeup attempt redirected to saved_state will fail.
282  *
283  * The lock operation looks like this:
284  *
285  *	current_save_and_set_rtlock_wait_state();
286  *	for (;;) {
287  *		if (try_lock())
288  *			break;
289  *		raw_spin_unlock_irq(&lock->wait_lock);
290  *		schedule_rtlock();
291  *		raw_spin_lock_irq(&lock->wait_lock);
292  *		set_current_state(TASK_RTLOCK_WAIT);
293  *	}
294  *	current_restore_rtlock_saved_state();
295  */
296 #define current_save_and_set_rtlock_wait_state()			\
297 	do {								\
298 		lockdep_assert_irqs_disabled();				\
299 		raw_spin_lock(&current->pi_lock);			\
300 		current->saved_state = current->__state;		\
301 		debug_rtlock_wait_set_state();				\
302 		trace_set_current_state(TASK_RTLOCK_WAIT);		\
303 		WRITE_ONCE(current->__state, TASK_RTLOCK_WAIT);		\
304 		raw_spin_unlock(&current->pi_lock);			\
305 	} while (0);
306 
307 #define current_restore_rtlock_saved_state()				\
308 	do {								\
309 		lockdep_assert_irqs_disabled();				\
310 		raw_spin_lock(&current->pi_lock);			\
311 		debug_rtlock_wait_restore_state();			\
312 		trace_set_current_state(current->saved_state);		\
313 		WRITE_ONCE(current->__state, current->saved_state);	\
314 		current->saved_state = TASK_RUNNING;			\
315 		raw_spin_unlock(&current->pi_lock);			\
316 	} while (0);
317 
318 #define get_current_state()	READ_ONCE(current->__state)
319 
320 /*
321  * Define the task command name length as enum, then it can be visible to
322  * BPF programs.
323  */
324 enum {
325 	TASK_COMM_LEN = 16,
326 };
327 
328 extern void sched_tick(void);
329 
330 #define	MAX_SCHEDULE_TIMEOUT		LONG_MAX
331 
332 extern long schedule_timeout(long timeout);
333 extern long schedule_timeout_interruptible(long timeout);
334 extern long schedule_timeout_killable(long timeout);
335 extern long schedule_timeout_uninterruptible(long timeout);
336 extern long schedule_timeout_idle(long timeout);
337 asmlinkage void schedule(void);
338 extern void schedule_preempt_disabled(void);
339 asmlinkage void preempt_schedule_irq(void);
340 #ifdef CONFIG_PREEMPT_RT
341  extern void schedule_rtlock(void);
342 #endif
343 
344 extern int __must_check io_schedule_prepare(void);
345 extern void io_schedule_finish(int token);
346 extern long io_schedule_timeout(long timeout);
347 extern void io_schedule(void);
348 
349 /* wrapper functions to trace from this header file */
350 DECLARE_TRACEPOINT(sched_set_state_tp);
351 extern void __trace_set_current_state(int state_value);
352 DECLARE_TRACEPOINT(sched_set_need_resched_tp);
353 extern void __trace_set_need_resched(struct task_struct *curr, int tif);
354 
355 /**
356  * struct prev_cputime - snapshot of system and user cputime
357  * @utime: time spent in user mode
358  * @stime: time spent in system mode
359  * @lock: protects the above two fields
360  *
361  * Stores previous user/system time values such that we can guarantee
362  * monotonicity.
363  */
364 struct prev_cputime {
365 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
366 	u64				utime;
367 	u64				stime;
368 	raw_spinlock_t			lock;
369 #endif
370 };
371 
372 enum vtime_state {
373 	/* Task is sleeping or running in a CPU with VTIME inactive: */
374 	VTIME_INACTIVE = 0,
375 	/* Task is idle */
376 	VTIME_IDLE,
377 	/* Task runs in kernelspace in a CPU with VTIME active: */
378 	VTIME_SYS,
379 	/* Task runs in userspace in a CPU with VTIME active: */
380 	VTIME_USER,
381 	/* Task runs as guests in a CPU with VTIME active: */
382 	VTIME_GUEST,
383 };
384 
385 struct vtime {
386 	seqcount_t		seqcount;
387 	unsigned long long	starttime;
388 	enum vtime_state	state;
389 	unsigned int		cpu;
390 	u64			utime;
391 	u64			stime;
392 	u64			gtime;
393 };
394 
395 /*
396  * Utilization clamp constraints.
397  * @UCLAMP_MIN:	Minimum utilization
398  * @UCLAMP_MAX:	Maximum utilization
399  * @UCLAMP_CNT:	Utilization clamp constraints count
400  */
401 enum uclamp_id {
402 	UCLAMP_MIN = 0,
403 	UCLAMP_MAX,
404 	UCLAMP_CNT
405 };
406 
407 extern struct root_domain def_root_domain;
408 extern struct mutex sched_domains_mutex;
409 extern void sched_domains_mutex_lock(void);
410 extern void sched_domains_mutex_unlock(void);
411 
412 struct sched_param {
413 	int sched_priority;
414 };
415 
416 struct sched_info {
417 #ifdef CONFIG_SCHED_INFO
418 	/* Cumulative counters: */
419 
420 	/* # of times we have run on this CPU: */
421 	unsigned long			pcount;
422 
423 	/* Time spent waiting on a runqueue: */
424 	unsigned long long		run_delay;
425 
426 	/* Max time spent waiting on a runqueue: */
427 	unsigned long long		max_run_delay;
428 
429 	/* Min time spent waiting on a runqueue: */
430 	unsigned long long		min_run_delay;
431 
432 	/* Timestamps: */
433 
434 	/* When did we last run on a CPU? */
435 	unsigned long long		last_arrival;
436 
437 	/* When were we last queued to run? */
438 	unsigned long long		last_queued;
439 
440 	/* Timestamp of max time spent waiting on a runqueue: */
441 	struct timespec64		max_run_delay_ts;
442 
443 #endif /* CONFIG_SCHED_INFO */
444 };
445 
446 /*
447  * Integer metrics need fixed point arithmetic, e.g., sched/fair
448  * has a few: load, load_avg, util_avg, freq, and capacity.
449  *
450  * We define a basic fixed point arithmetic range, and then formalize
451  * all these metrics based on that basic range.
452  */
453 # define SCHED_FIXEDPOINT_SHIFT		10
454 # define SCHED_FIXEDPOINT_SCALE		(1L << SCHED_FIXEDPOINT_SHIFT)
455 
456 /* Increase resolution of cpu_capacity calculations */
457 # define SCHED_CAPACITY_SHIFT		SCHED_FIXEDPOINT_SHIFT
458 # define SCHED_CAPACITY_SCALE		(1L << SCHED_CAPACITY_SHIFT)
459 
460 struct load_weight {
461 	unsigned long			weight;
462 	u32				inv_weight;
463 };
464 
465 /*
466  * The load/runnable/util_avg accumulates an infinite geometric series
467  * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c).
468  *
469  * [load_avg definition]
470  *
471  *   load_avg = runnable% * scale_load_down(load)
472  *
473  * [runnable_avg definition]
474  *
475  *   runnable_avg = runnable% * SCHED_CAPACITY_SCALE
476  *
477  * [util_avg definition]
478  *
479  *   util_avg = running% * SCHED_CAPACITY_SCALE
480  *
481  * where runnable% is the time ratio that a sched_entity is runnable and
482  * running% the time ratio that a sched_entity is running.
483  *
484  * For cfs_rq, they are the aggregated values of all runnable and blocked
485  * sched_entities.
486  *
487  * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU
488  * capacity scaling. The scaling is done through the rq_clock_pelt that is used
489  * for computing those signals (see update_rq_clock_pelt())
490  *
491  * N.B., the above ratios (runnable% and running%) themselves are in the
492  * range of [0, 1]. To do fixed point arithmetics, we therefore scale them
493  * to as large a range as necessary. This is for example reflected by
494  * util_avg's SCHED_CAPACITY_SCALE.
495  *
496  * [Overflow issue]
497  *
498  * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
499  * with the highest load (=88761), always runnable on a single cfs_rq,
500  * and should not overflow as the number already hits PID_MAX_LIMIT.
501  *
502  * For all other cases (including 32-bit kernels), struct load_weight's
503  * weight will overflow first before we do, because:
504  *
505  *    Max(load_avg) <= Max(load.weight)
506  *
507  * Then it is the load_weight's responsibility to consider overflow
508  * issues.
509  */
510 struct sched_avg {
511 	u64				last_update_time;
512 	u64				load_sum;
513 	u64				runnable_sum;
514 	u32				util_sum;
515 	u32				period_contrib;
516 	unsigned long			load_avg;
517 	unsigned long			runnable_avg;
518 	unsigned long			util_avg;
519 	unsigned int			util_est;
520 } ____cacheline_aligned;
521 
522 /*
523  * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg
524  * updates. When a task is dequeued, its util_est should not be updated if its
525  * util_avg has not been updated in the meantime.
526  * This information is mapped into the MSB bit of util_est at dequeue time.
527  * Since max value of util_est for a task is 1024 (PELT util_avg for a task)
528  * it is safe to use MSB.
529  */
530 #define UTIL_EST_WEIGHT_SHIFT		2
531 #define UTIL_AVG_UNCHANGED		0x80000000
532 
533 struct sched_statistics {
534 #ifdef CONFIG_SCHEDSTATS
535 	u64				wait_start;
536 	u64				wait_max;
537 	u64				wait_count;
538 	u64				wait_sum;
539 	u64				iowait_count;
540 	u64				iowait_sum;
541 
542 	u64				sleep_start;
543 	u64				sleep_max;
544 	s64				sum_sleep_runtime;
545 
546 	u64				block_start;
547 	u64				block_max;
548 	s64				sum_block_runtime;
549 
550 	s64				exec_max;
551 	u64				slice_max;
552 
553 	u64				nr_migrations_cold;
554 	u64				nr_failed_migrations_affine;
555 	u64				nr_failed_migrations_running;
556 	u64				nr_failed_migrations_hot;
557 	u64				nr_forced_migrations;
558 
559 	u64				nr_wakeups;
560 	u64				nr_wakeups_sync;
561 	u64				nr_wakeups_migrate;
562 	u64				nr_wakeups_local;
563 	u64				nr_wakeups_remote;
564 	u64				nr_wakeups_affine;
565 	u64				nr_wakeups_affine_attempts;
566 	u64				nr_wakeups_passive;
567 	u64				nr_wakeups_idle;
568 
569 #ifdef CONFIG_SCHED_CORE
570 	u64				core_forceidle_sum;
571 #endif
572 #endif /* CONFIG_SCHEDSTATS */
573 } ____cacheline_aligned;
574 
575 struct sched_entity {
576 	/* For load-balancing: */
577 	struct load_weight		load;
578 	struct rb_node			run_node;
579 	u64				deadline;
580 	u64				min_vruntime;
581 	u64				min_slice;
582 
583 	struct list_head		group_node;
584 	unsigned char			on_rq;
585 	unsigned char			sched_delayed;
586 	unsigned char			rel_deadline;
587 	unsigned char			custom_slice;
588 					/* hole */
589 
590 	u64				exec_start;
591 	u64				sum_exec_runtime;
592 	u64				prev_sum_exec_runtime;
593 	u64				vruntime;
594 	/* Approximated virtual lag: */
595 	s64				vlag;
596 	/* 'Protected' deadline, to give out minimum quantums: */
597 	u64				vprot;
598 	u64				slice;
599 
600 	u64				nr_migrations;
601 
602 #ifdef CONFIG_FAIR_GROUP_SCHED
603 	int				depth;
604 	struct sched_entity		*parent;
605 	/* rq on which this entity is (to be) queued: */
606 	struct cfs_rq			*cfs_rq;
607 	/* rq "owned" by this entity/group: */
608 	struct cfs_rq			*my_q;
609 	/* cached value of my_q->h_nr_running */
610 	unsigned long			runnable_weight;
611 #endif
612 
613 	/*
614 	 * Per entity load average tracking.
615 	 *
616 	 * Put into separate cache line so it does not
617 	 * collide with read-mostly values above.
618 	 */
619 	struct sched_avg		avg;
620 };
621 
622 struct sched_rt_entity {
623 	struct list_head		run_list;
624 	unsigned long			timeout;
625 	unsigned long			watchdog_stamp;
626 	unsigned int			time_slice;
627 	unsigned short			on_rq;
628 	unsigned short			on_list;
629 
630 	struct sched_rt_entity		*back;
631 #ifdef CONFIG_RT_GROUP_SCHED
632 	struct sched_rt_entity		*parent;
633 	/* rq on which this entity is (to be) queued: */
634 	struct rt_rq			*rt_rq;
635 	/* rq "owned" by this entity/group: */
636 	struct rt_rq			*my_q;
637 #endif
638 } __randomize_layout;
639 
640 struct rq_flags;
641 typedef struct task_struct *(*dl_server_pick_f)(struct sched_dl_entity *, struct rq_flags *rf);
642 
643 struct sched_dl_entity {
644 	struct rb_node			rb_node;
645 
646 	/*
647 	 * Original scheduling parameters. Copied here from sched_attr
648 	 * during sched_setattr(), they will remain the same until
649 	 * the next sched_setattr().
650 	 */
651 	u64				dl_runtime;	/* Maximum runtime for each instance	*/
652 	u64				dl_deadline;	/* Relative deadline of each instance	*/
653 	u64				dl_period;	/* Separation of two instances (period) */
654 	u64				dl_bw;		/* dl_runtime / dl_period		*/
655 	u64				dl_density;	/* dl_runtime / dl_deadline		*/
656 
657 	/*
658 	 * Actual scheduling parameters. Initialized with the values above,
659 	 * they are continuously updated during task execution. Note that
660 	 * the remaining runtime could be < 0 in case we are in overrun.
661 	 */
662 	s64				runtime;	/* Remaining runtime for this instance	*/
663 	u64				deadline;	/* Absolute deadline for this instance	*/
664 	unsigned int			flags;		/* Specifying the scheduler behaviour	*/
665 
666 	/*
667 	 * Some bool flags:
668 	 *
669 	 * @dl_throttled tells if we exhausted the runtime. If so, the
670 	 * task has to wait for a replenishment to be performed at the
671 	 * next firing of dl_timer.
672 	 *
673 	 * @dl_yielded tells if task gave up the CPU before consuming
674 	 * all its available runtime during the last job.
675 	 *
676 	 * @dl_non_contending tells if the task is inactive while still
677 	 * contributing to the active utilization. In other words, it
678 	 * indicates if the inactive timer has been armed and its handler
679 	 * has not been executed yet. This flag is useful to avoid race
680 	 * conditions between the inactive timer handler and the wakeup
681 	 * code.
682 	 *
683 	 * @dl_overrun tells if the task asked to be informed about runtime
684 	 * overruns.
685 	 *
686 	 * @dl_server tells if this is a server entity.
687 	 *
688 	 * @dl_server_active tells if the dlserver is active(started).
689 	 * dlserver is started on first cfs enqueue on an idle runqueue
690 	 * and is stopped when a dequeue results in 0 cfs tasks on the
691 	 * runqueue. In other words, dlserver is active only when cpu's
692 	 * runqueue has atleast one cfs task.
693 	 *
694 	 * @dl_defer tells if this is a deferred or regular server. For
695 	 * now only defer server exists.
696 	 *
697 	 * @dl_defer_armed tells if the deferrable server is waiting
698 	 * for the replenishment timer to activate it.
699 	 *
700 	 * @dl_defer_running tells if the deferrable server is actually
701 	 * running, skipping the defer phase.
702 	 *
703 	 * @dl_defer_idle tracks idle state
704 	 */
705 	unsigned int			dl_throttled      : 1;
706 	unsigned int			dl_yielded        : 1;
707 	unsigned int			dl_non_contending : 1;
708 	unsigned int			dl_overrun	  : 1;
709 	unsigned int			dl_server         : 1;
710 	unsigned int			dl_server_active  : 1;
711 	unsigned int			dl_defer	  : 1;
712 	unsigned int			dl_defer_armed	  : 1;
713 	unsigned int			dl_defer_running  : 1;
714 	unsigned int			dl_defer_idle     : 1;
715 
716 	/*
717 	 * Bandwidth enforcement timer. Each -deadline task has its
718 	 * own bandwidth to be enforced, thus we need one timer per task.
719 	 */
720 	struct hrtimer			dl_timer;
721 
722 	/*
723 	 * Inactive timer, responsible for decreasing the active utilization
724 	 * at the "0-lag time". When a -deadline task blocks, it contributes
725 	 * to GRUB's active utilization until the "0-lag time", hence a
726 	 * timer is needed to decrease the active utilization at the correct
727 	 * time.
728 	 */
729 	struct hrtimer			inactive_timer;
730 
731 	/*
732 	 * Bits for DL-server functionality. Also see the comment near
733 	 * dl_server_update().
734 	 *
735 	 * @rq the runqueue this server is for
736 	 */
737 	struct rq			*rq;
738 	dl_server_pick_f		server_pick_task;
739 
740 #ifdef CONFIG_RT_MUTEXES
741 	/*
742 	 * Priority Inheritance. When a DEADLINE scheduling entity is boosted
743 	 * pi_se points to the donor, otherwise points to the dl_se it belongs
744 	 * to (the original one/itself).
745 	 */
746 	struct sched_dl_entity *pi_se;
747 #endif
748 };
749 
750 #ifdef CONFIG_UCLAMP_TASK
751 /* Number of utilization clamp buckets (shorter alias) */
752 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT
753 
754 /*
755  * Utilization clamp for a scheduling entity
756  * @value:		clamp value "assigned" to a se
757  * @bucket_id:		bucket index corresponding to the "assigned" value
758  * @active:		the se is currently refcounted in a rq's bucket
759  * @user_defined:	the requested clamp value comes from user-space
760  *
761  * The bucket_id is the index of the clamp bucket matching the clamp value
762  * which is pre-computed and stored to avoid expensive integer divisions from
763  * the fast path.
764  *
765  * The active bit is set whenever a task has got an "effective" value assigned,
766  * which can be different from the clamp value "requested" from user-space.
767  * This allows to know a task is refcounted in the rq's bucket corresponding
768  * to the "effective" bucket_id.
769  *
770  * The user_defined bit is set whenever a task has got a task-specific clamp
771  * value requested from userspace, i.e. the system defaults apply to this task
772  * just as a restriction. This allows to relax default clamps when a less
773  * restrictive task-specific value has been requested, thus allowing to
774  * implement a "nice" semantic. For example, a task running with a 20%
775  * default boost can still drop its own boosting to 0%.
776  */
777 struct uclamp_se {
778 	unsigned int value		: bits_per(SCHED_CAPACITY_SCALE);
779 	unsigned int bucket_id		: bits_per(UCLAMP_BUCKETS);
780 	unsigned int active		: 1;
781 	unsigned int user_defined	: 1;
782 };
783 #endif /* CONFIG_UCLAMP_TASK */
784 
785 union rcu_special {
786 	struct {
787 		u8			blocked;
788 		u8			need_qs;
789 		u8			exp_hint; /* Hint for performance. */
790 		u8			need_mb; /* Readers need smp_mb(). */
791 	} b; /* Bits. */
792 	u32 s; /* Set of bits. */
793 };
794 
795 enum perf_event_task_context {
796 	perf_invalid_context = -1,
797 	perf_hw_context = 0,
798 	perf_sw_context,
799 	perf_nr_task_contexts,
800 };
801 
802 /*
803  * Number of contexts where an event can trigger:
804  *      task, softirq, hardirq, nmi.
805  */
806 #define PERF_NR_CONTEXTS	4
807 
808 struct wake_q_node {
809 	struct wake_q_node *next;
810 };
811 
812 struct kmap_ctrl {
813 #ifdef CONFIG_KMAP_LOCAL
814 	int				idx;
815 	pte_t				pteval[KM_MAX_IDX];
816 #endif
817 };
818 
819 struct task_struct {
820 #ifdef CONFIG_THREAD_INFO_IN_TASK
821 	/*
822 	 * For reasons of header soup (see current_thread_info()), this
823 	 * must be the first element of task_struct.
824 	 */
825 	struct thread_info		thread_info;
826 #endif
827 	unsigned int			__state;
828 
829 	/* saved state for "spinlock sleepers" */
830 	unsigned int			saved_state;
831 
832 	/*
833 	 * This begins the randomizable portion of task_struct. Only
834 	 * scheduling-critical items should be added above here.
835 	 */
836 	randomized_struct_fields_start
837 
838 	void				*stack;
839 	refcount_t			usage;
840 	/* Per task flags (PF_*), defined further below: */
841 	unsigned int			flags;
842 	unsigned int			ptrace;
843 
844 #ifdef CONFIG_MEM_ALLOC_PROFILING
845 	struct alloc_tag		*alloc_tag;
846 #endif
847 
848 	int				on_cpu;
849 	struct __call_single_node	wake_entry;
850 	unsigned int			wakee_flips;
851 	unsigned long			wakee_flip_decay_ts;
852 	struct task_struct		*last_wakee;
853 
854 	/*
855 	 * recent_used_cpu is initially set as the last CPU used by a task
856 	 * that wakes affine another task. Waker/wakee relationships can
857 	 * push tasks around a CPU where each wakeup moves to the next one.
858 	 * Tracking a recently used CPU allows a quick search for a recently
859 	 * used CPU that may be idle.
860 	 */
861 	int				recent_used_cpu;
862 	int				wake_cpu;
863 	int				on_rq;
864 
865 	int				prio;
866 	int				static_prio;
867 	int				normal_prio;
868 	unsigned int			rt_priority;
869 
870 	struct sched_entity		se;
871 	struct sched_rt_entity		rt;
872 	struct sched_dl_entity		dl;
873 	struct sched_dl_entity		*dl_server;
874 #ifdef CONFIG_SCHED_CLASS_EXT
875 	struct sched_ext_entity		scx;
876 #endif
877 	const struct sched_class	*sched_class;
878 
879 #ifdef CONFIG_SCHED_CORE
880 	struct rb_node			core_node;
881 	unsigned long			core_cookie;
882 	unsigned int			core_occupation;
883 #endif
884 
885 #ifdef CONFIG_CGROUP_SCHED
886 	struct task_group		*sched_task_group;
887 #ifdef CONFIG_CFS_BANDWIDTH
888 	struct callback_head		sched_throttle_work;
889 	struct list_head		throttle_node;
890 	bool				throttled;
891 #endif
892 #endif
893 
894 
895 #ifdef CONFIG_UCLAMP_TASK
896 	/*
897 	 * Clamp values requested for a scheduling entity.
898 	 * Must be updated with task_rq_lock() held.
899 	 */
900 	struct uclamp_se		uclamp_req[UCLAMP_CNT];
901 	/*
902 	 * Effective clamp values used for a scheduling entity.
903 	 * Must be updated with task_rq_lock() held.
904 	 */
905 	struct uclamp_se		uclamp[UCLAMP_CNT];
906 #endif
907 
908 	struct sched_statistics         stats;
909 
910 #ifdef CONFIG_PREEMPT_NOTIFIERS
911 	/* List of struct preempt_notifier: */
912 	struct hlist_head		preempt_notifiers;
913 #endif
914 
915 #ifdef CONFIG_BLK_DEV_IO_TRACE
916 	unsigned int			btrace_seq;
917 #endif
918 
919 	unsigned int			policy;
920 	unsigned long			max_allowed_capacity;
921 	int				nr_cpus_allowed;
922 	const cpumask_t			*cpus_ptr;
923 	cpumask_t			*user_cpus_ptr;
924 	cpumask_t			cpus_mask;
925 	void				*migration_pending;
926 	unsigned short			migration_disabled;
927 	unsigned short			migration_flags;
928 
929 #ifdef CONFIG_PREEMPT_RCU
930 	int				rcu_read_lock_nesting;
931 	union rcu_special		rcu_read_unlock_special;
932 	struct list_head		rcu_node_entry;
933 	struct rcu_node			*rcu_blocked_node;
934 #endif /* #ifdef CONFIG_PREEMPT_RCU */
935 
936 #ifdef CONFIG_TASKS_RCU
937 	unsigned long			rcu_tasks_nvcsw;
938 	u8				rcu_tasks_holdout;
939 	u8				rcu_tasks_idx;
940 	int				rcu_tasks_idle_cpu;
941 	struct list_head		rcu_tasks_holdout_list;
942 	int				rcu_tasks_exit_cpu;
943 	struct list_head		rcu_tasks_exit_list;
944 #endif /* #ifdef CONFIG_TASKS_RCU */
945 
946 #ifdef CONFIG_TASKS_TRACE_RCU
947 	int				trc_reader_nesting;
948 	struct srcu_ctr __percpu	*trc_reader_scp;
949 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */
950 
951 	struct sched_info		sched_info;
952 
953 	struct list_head		tasks;
954 	struct plist_node		pushable_tasks;
955 	struct rb_node			pushable_dl_tasks;
956 
957 	struct mm_struct		*mm;
958 	struct mm_struct		*active_mm;
959 
960 	int				exit_state;
961 	int				exit_code;
962 	int				exit_signal;
963 	/* The signal sent when the parent dies: */
964 	int				pdeath_signal;
965 	/* JOBCTL_*, siglock protected: */
966 	unsigned long			jobctl;
967 
968 	/* Used for emulating ABI behavior of previous Linux versions: */
969 	unsigned int			personality;
970 
971 	/* Scheduler bits, serialized by scheduler locks: */
972 	unsigned			sched_reset_on_fork:1;
973 	unsigned			sched_contributes_to_load:1;
974 	unsigned			sched_migrated:1;
975 	unsigned			sched_task_hot:1;
976 
977 	/* Force alignment to the next boundary: */
978 	unsigned			:0;
979 
980 	/* Unserialized, strictly 'current' */
981 
982 	/*
983 	 * This field must not be in the scheduler word above due to wakelist
984 	 * queueing no longer being serialized by p->on_cpu. However:
985 	 *
986 	 * p->XXX = X;			ttwu()
987 	 * schedule()			  if (p->on_rq && ..) // false
988 	 *   smp_mb__after_spinlock();	  if (smp_load_acquire(&p->on_cpu) && //true
989 	 *   deactivate_task()		      ttwu_queue_wakelist())
990 	 *     p->on_rq = 0;			p->sched_remote_wakeup = Y;
991 	 *
992 	 * guarantees all stores of 'current' are visible before
993 	 * ->sched_remote_wakeup gets used, so it can be in this word.
994 	 */
995 	unsigned			sched_remote_wakeup:1;
996 #ifdef CONFIG_RT_MUTEXES
997 	unsigned			sched_rt_mutex:1;
998 #endif
999 
1000 	/* Bit to tell TOMOYO we're in execve(): */
1001 	unsigned			in_execve:1;
1002 	unsigned			in_iowait:1;
1003 #ifndef TIF_RESTORE_SIGMASK
1004 	unsigned			restore_sigmask:1;
1005 #endif
1006 #ifdef CONFIG_MEMCG_V1
1007 	unsigned			in_user_fault:1;
1008 #endif
1009 #ifdef CONFIG_LRU_GEN
1010 	/* whether the LRU algorithm may apply to this access */
1011 	unsigned			in_lru_fault:1;
1012 #endif
1013 #ifdef CONFIG_COMPAT_BRK
1014 	unsigned			brk_randomized:1;
1015 #endif
1016 #ifdef CONFIG_CGROUPS
1017 	/* disallow userland-initiated cgroup migration */
1018 	unsigned			no_cgroup_migration:1;
1019 	/* task is frozen/stopped (used by the cgroup freezer) */
1020 	unsigned			frozen:1;
1021 #endif
1022 #ifdef CONFIG_BLK_CGROUP
1023 	unsigned			use_memdelay:1;
1024 #endif
1025 #ifdef CONFIG_PSI
1026 	/* Stalled due to lack of memory */
1027 	unsigned			in_memstall:1;
1028 #endif
1029 #ifdef CONFIG_PAGE_OWNER
1030 	/* Used by page_owner=on to detect recursion in page tracking. */
1031 	unsigned			in_page_owner:1;
1032 #endif
1033 #ifdef CONFIG_EVENTFD
1034 	/* Recursion prevention for eventfd_signal() */
1035 	unsigned			in_eventfd:1;
1036 #endif
1037 #ifdef CONFIG_ARCH_HAS_CPU_PASID
1038 	unsigned			pasid_activated:1;
1039 #endif
1040 #ifdef CONFIG_X86_BUS_LOCK_DETECT
1041 	unsigned			reported_split_lock:1;
1042 #endif
1043 #ifdef CONFIG_TASK_DELAY_ACCT
1044 	/* delay due to memory thrashing */
1045 	unsigned                        in_thrashing:1;
1046 #endif
1047 	unsigned			in_nf_duplicate:1;
1048 #ifdef CONFIG_PREEMPT_RT
1049 	struct netdev_xmit		net_xmit;
1050 #endif
1051 	unsigned long			atomic_flags; /* Flags requiring atomic access. */
1052 
1053 	struct restart_block		restart_block;
1054 
1055 	pid_t				pid;
1056 	pid_t				tgid;
1057 
1058 #ifdef CONFIG_STACKPROTECTOR
1059 	/* Canary value for the -fstack-protector GCC feature: */
1060 	unsigned long			stack_canary;
1061 #endif
1062 	/*
1063 	 * Pointers to the (original) parent process, youngest child, younger sibling,
1064 	 * older sibling, respectively.  (p->father can be replaced with
1065 	 * p->real_parent->pid)
1066 	 */
1067 
1068 	/* Real parent process: */
1069 	struct task_struct __rcu	*real_parent;
1070 
1071 	/* Recipient of SIGCHLD, wait4() reports: */
1072 	struct task_struct __rcu	*parent;
1073 
1074 	/*
1075 	 * Children/sibling form the list of natural children:
1076 	 */
1077 	struct list_head		children;
1078 	struct list_head		sibling;
1079 	struct task_struct		*group_leader;
1080 
1081 	/*
1082 	 * 'ptraced' is the list of tasks this task is using ptrace() on.
1083 	 *
1084 	 * This includes both natural children and PTRACE_ATTACH targets.
1085 	 * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
1086 	 */
1087 	struct list_head		ptraced;
1088 	struct list_head		ptrace_entry;
1089 
1090 	/* PID/PID hash table linkage. */
1091 	struct pid			*thread_pid;
1092 	struct hlist_node		pid_links[PIDTYPE_MAX];
1093 	struct list_head		thread_node;
1094 
1095 	struct completion		*vfork_done;
1096 
1097 	/* CLONE_CHILD_SETTID: */
1098 	int __user			*set_child_tid;
1099 
1100 	/* CLONE_CHILD_CLEARTID: */
1101 	int __user			*clear_child_tid;
1102 
1103 	/* PF_KTHREAD | PF_IO_WORKER */
1104 	void				*worker_private;
1105 
1106 	u64				utime;
1107 	u64				stime;
1108 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
1109 	u64				utimescaled;
1110 	u64				stimescaled;
1111 #endif
1112 	u64				gtime;
1113 	struct prev_cputime		prev_cputime;
1114 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1115 	struct vtime			vtime;
1116 #endif
1117 
1118 #ifdef CONFIG_NO_HZ_FULL
1119 	atomic_t			tick_dep_mask;
1120 #endif
1121 	/* Context switch counts: */
1122 	unsigned long			nvcsw;
1123 	unsigned long			nivcsw;
1124 
1125 	/* Monotonic time in nsecs: */
1126 	u64				start_time;
1127 
1128 	/* Boot based time in nsecs: */
1129 	u64				start_boottime;
1130 
1131 	/* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
1132 	unsigned long			min_flt;
1133 	unsigned long			maj_flt;
1134 
1135 	/* Empty if CONFIG_POSIX_CPUTIMERS=n */
1136 	struct posix_cputimers		posix_cputimers;
1137 
1138 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK
1139 	struct posix_cputimers_work	posix_cputimers_work;
1140 #endif
1141 
1142 	/* Process credentials: */
1143 
1144 	/* Tracer's credentials at attach: */
1145 	const struct cred __rcu		*ptracer_cred;
1146 
1147 	/* Objective and real subjective task credentials (COW): */
1148 	const struct cred __rcu		*real_cred;
1149 
1150 	/* Effective (overridable) subjective task credentials (COW): */
1151 	const struct cred __rcu		*cred;
1152 
1153 #ifdef CONFIG_KEYS
1154 	/* Cached requested key. */
1155 	struct key			*cached_requested_key;
1156 #endif
1157 
1158 	/*
1159 	 * executable name, excluding path.
1160 	 *
1161 	 * - normally initialized begin_new_exec()
1162 	 * - set it with set_task_comm()
1163 	 *   - strscpy_pad() to ensure it is always NUL-terminated and
1164 	 *     zero-padded
1165 	 *   - task_lock() to ensure the operation is atomic and the name is
1166 	 *     fully updated.
1167 	 */
1168 	char				comm[TASK_COMM_LEN];
1169 
1170 	struct nameidata		*nameidata;
1171 
1172 #ifdef CONFIG_SYSVIPC
1173 	struct sysv_sem			sysvsem;
1174 	struct sysv_shm			sysvshm;
1175 #endif
1176 #ifdef CONFIG_DETECT_HUNG_TASK
1177 	unsigned long			last_switch_count;
1178 	unsigned long			last_switch_time;
1179 #endif
1180 	/* Filesystem information: */
1181 	struct fs_struct		*fs;
1182 
1183 	/* Open file information: */
1184 	struct files_struct		*files;
1185 
1186 #ifdef CONFIG_IO_URING
1187 	struct io_uring_task		*io_uring;
1188 	struct io_restriction		*io_uring_restrict;
1189 #endif
1190 
1191 	/* Namespaces: */
1192 	struct nsproxy			*nsproxy;
1193 
1194 	/* Signal handlers: */
1195 	struct signal_struct		*signal;
1196 	struct sighand_struct __rcu		*sighand;
1197 	sigset_t			blocked;
1198 	sigset_t			real_blocked;
1199 	/* Restored if set_restore_sigmask() was used: */
1200 	sigset_t			saved_sigmask;
1201 	struct sigpending		pending;
1202 	unsigned long			sas_ss_sp;
1203 	size_t				sas_ss_size;
1204 	unsigned int			sas_ss_flags;
1205 
1206 	struct callback_head		*task_works;
1207 
1208 #ifdef CONFIG_AUDIT
1209 #ifdef CONFIG_AUDITSYSCALL
1210 	struct audit_context		*audit_context;
1211 #endif
1212 	kuid_t				loginuid;
1213 	unsigned int			sessionid;
1214 #endif
1215 	struct seccomp			seccomp;
1216 	struct syscall_user_dispatch	syscall_dispatch;
1217 
1218 	/* Thread group tracking: */
1219 	u64				parent_exec_id;
1220 	u64				self_exec_id;
1221 
1222 	/* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
1223 	spinlock_t			alloc_lock;
1224 
1225 	/* Protection of the PI data structures: */
1226 	raw_spinlock_t			pi_lock;
1227 
1228 	struct wake_q_node		wake_q;
1229 
1230 #ifdef CONFIG_RT_MUTEXES
1231 	/* PI waiters blocked on a rt_mutex held by this task: */
1232 	struct rb_root_cached		pi_waiters;
1233 	/* Updated under owner's pi_lock and rq lock */
1234 	struct task_struct		*pi_top_task;
1235 	/* Deadlock detection and priority inheritance handling: */
1236 	struct rt_mutex_waiter		*pi_blocked_on;
1237 #endif
1238 
1239 	struct mutex			*blocked_on;	/* lock we're blocked on */
1240 
1241 #ifdef CONFIG_DETECT_HUNG_TASK_BLOCKER
1242 	/*
1243 	 * Encoded lock address causing task block (lower 2 bits = type from
1244 	 * <linux/hung_task.h>). Accessed via hung_task_*() helpers.
1245 	 */
1246 	unsigned long			blocker;
1247 #endif
1248 
1249 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1250 	int				non_block_count;
1251 #endif
1252 
1253 #ifdef CONFIG_TRACE_IRQFLAGS
1254 	struct irqtrace_events		irqtrace;
1255 	unsigned int			hardirq_threaded;
1256 	u64				hardirq_chain_key;
1257 	int				softirqs_enabled;
1258 	int				softirq_context;
1259 	int				irq_config;
1260 #endif
1261 #ifdef CONFIG_PREEMPT_RT
1262 	int				softirq_disable_cnt;
1263 #endif
1264 
1265 #ifdef CONFIG_LOCKDEP
1266 # define MAX_LOCK_DEPTH			48UL
1267 	u64				curr_chain_key;
1268 	int				lockdep_depth;
1269 	unsigned int			lockdep_recursion;
1270 	struct held_lock		held_locks[MAX_LOCK_DEPTH];
1271 #endif
1272 
1273 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP)
1274 	unsigned int			in_ubsan;
1275 #endif
1276 
1277 	/* Journalling filesystem info: */
1278 	void				*journal_info;
1279 
1280 	/* Stacked block device info: */
1281 	struct bio_list			*bio_list;
1282 
1283 	/* Stack plugging: */
1284 	struct blk_plug			*plug;
1285 
1286 	/* VM state: */
1287 	struct reclaim_state		*reclaim_state;
1288 
1289 	struct io_context		*io_context;
1290 
1291 #ifdef CONFIG_COMPACTION
1292 	struct capture_control		*capture_control;
1293 #endif
1294 	/* Ptrace state: */
1295 	unsigned long			ptrace_message;
1296 	kernel_siginfo_t		*last_siginfo;
1297 
1298 	struct task_io_accounting	ioac;
1299 #ifdef CONFIG_PSI
1300 	/* Pressure stall state */
1301 	unsigned int			psi_flags;
1302 #endif
1303 #ifdef CONFIG_TASK_XACCT
1304 	/* Accumulated RSS usage: */
1305 	u64				acct_rss_mem1;
1306 	/* Accumulated virtual memory usage: */
1307 	u64				acct_vm_mem1;
1308 	/* stime + utime since last update: */
1309 	u64				acct_timexpd;
1310 #endif
1311 #ifdef CONFIG_CPUSETS
1312 	/* Protected by ->alloc_lock: */
1313 	nodemask_t			mems_allowed;
1314 	/* Sequence number to catch updates: */
1315 	seqcount_spinlock_t		mems_allowed_seq;
1316 	int				cpuset_mem_spread_rotor;
1317 #endif
1318 #ifdef CONFIG_CGROUPS
1319 	/* Control Group info protected by css_set_lock: */
1320 	struct css_set __rcu		*cgroups;
1321 	/* cg_list protected by css_set_lock and tsk->alloc_lock: */
1322 	struct list_head		cg_list;
1323 #ifdef CONFIG_PREEMPT_RT
1324 	struct llist_node		cg_dead_lnode;
1325 #endif	/* CONFIG_PREEMPT_RT */
1326 #endif	/* CONFIG_CGROUPS */
1327 #ifdef CONFIG_X86_CPU_RESCTRL
1328 	u32				closid;
1329 	u32				rmid;
1330 #endif
1331 #ifdef CONFIG_FUTEX
1332 	struct robust_list_head __user	*robust_list;
1333 #ifdef CONFIG_COMPAT
1334 	struct compat_robust_list_head __user *compat_robust_list;
1335 #endif
1336 	struct list_head		pi_state_list;
1337 	struct futex_pi_state		*pi_state_cache;
1338 	struct mutex			futex_exit_mutex;
1339 	unsigned int			futex_state;
1340 #endif
1341 #ifdef CONFIG_PERF_EVENTS
1342 	u8				perf_recursion[PERF_NR_CONTEXTS];
1343 	struct perf_event_context	*perf_event_ctxp;
1344 	struct mutex			perf_event_mutex;
1345 	struct list_head		perf_event_list;
1346 	struct perf_ctx_data __rcu	*perf_ctx_data;
1347 #endif
1348 #ifdef CONFIG_DEBUG_PREEMPT
1349 	unsigned long			preempt_disable_ip;
1350 #endif
1351 #ifdef CONFIG_NUMA
1352 	/* Protected by alloc_lock: */
1353 	struct mempolicy		*mempolicy;
1354 	short				il_prev;
1355 	u8				il_weight;
1356 	short				pref_node_fork;
1357 #endif
1358 #ifdef CONFIG_NUMA_BALANCING
1359 	int				numa_scan_seq;
1360 	unsigned int			numa_scan_period;
1361 	unsigned int			numa_scan_period_max;
1362 	int				numa_preferred_nid;
1363 	unsigned long			numa_migrate_retry;
1364 	/* Migration stamp: */
1365 	u64				node_stamp;
1366 	u64				last_task_numa_placement;
1367 	u64				last_sum_exec_runtime;
1368 	struct callback_head		numa_work;
1369 
1370 	/*
1371 	 * This pointer is only modified for current in syscall and
1372 	 * pagefault context (and for tasks being destroyed), so it can be read
1373 	 * from any of the following contexts:
1374 	 *  - RCU read-side critical section
1375 	 *  - current->numa_group from everywhere
1376 	 *  - task's runqueue locked, task not running
1377 	 */
1378 	struct numa_group __rcu		*numa_group;
1379 
1380 	/*
1381 	 * numa_faults is an array split into four regions:
1382 	 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1383 	 * in this precise order.
1384 	 *
1385 	 * faults_memory: Exponential decaying average of faults on a per-node
1386 	 * basis. Scheduling placement decisions are made based on these
1387 	 * counts. The values remain static for the duration of a PTE scan.
1388 	 * faults_cpu: Track the nodes the process was running on when a NUMA
1389 	 * hinting fault was incurred.
1390 	 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1391 	 * during the current scan window. When the scan completes, the counts
1392 	 * in faults_memory and faults_cpu decay and these values are copied.
1393 	 */
1394 	unsigned long			*numa_faults;
1395 	unsigned long			total_numa_faults;
1396 
1397 	/*
1398 	 * numa_faults_locality tracks if faults recorded during the last
1399 	 * scan window were remote/local or failed to migrate. The task scan
1400 	 * period is adapted based on the locality of the faults with different
1401 	 * weights depending on whether they were shared or private faults
1402 	 */
1403 	unsigned long			numa_faults_locality[3];
1404 
1405 	unsigned long			numa_pages_migrated;
1406 #endif /* CONFIG_NUMA_BALANCING */
1407 
1408 	struct rseq_data		rseq;
1409 	struct sched_mm_cid		mm_cid;
1410 
1411 	struct tlbflush_unmap_batch	tlb_ubc;
1412 
1413 	/* Cache last used pipe for splice(): */
1414 	struct pipe_inode_info		*splice_pipe;
1415 
1416 	struct page_frag		task_frag;
1417 
1418 #ifdef CONFIG_ARCH_HAS_LAZY_MMU_MODE
1419 	struct lazy_mmu_state		lazy_mmu_state;
1420 #endif
1421 
1422 #ifdef CONFIG_TASK_DELAY_ACCT
1423 	struct task_delay_info		*delays;
1424 #endif
1425 
1426 #ifdef CONFIG_FAULT_INJECTION
1427 	int				make_it_fail;
1428 	unsigned int			fail_nth;
1429 #endif
1430 	/*
1431 	 * When (nr_dirtied >= nr_dirtied_pause), it's time to call
1432 	 * balance_dirty_pages() for a dirty throttling pause:
1433 	 */
1434 	int				nr_dirtied;
1435 	int				nr_dirtied_pause;
1436 	/* Start of a write-and-pause period: */
1437 	unsigned long			dirty_paused_when;
1438 
1439 #ifdef CONFIG_LATENCYTOP
1440 	int				latency_record_count;
1441 	struct latency_record		latency_record[LT_SAVECOUNT];
1442 #endif
1443 	/*
1444 	 * Time slack values; these are used to round up poll() and
1445 	 * select() etc timeout values. These are in nanoseconds.
1446 	 */
1447 	u64				timer_slack_ns;
1448 	u64				default_timer_slack_ns;
1449 
1450 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
1451 	unsigned int			kasan_depth;
1452 #endif
1453 
1454 #ifdef CONFIG_KCSAN
1455 	struct kcsan_ctx		kcsan_ctx;
1456 #ifdef CONFIG_TRACE_IRQFLAGS
1457 	struct irqtrace_events		kcsan_save_irqtrace;
1458 #endif
1459 #ifdef CONFIG_KCSAN_WEAK_MEMORY
1460 	int				kcsan_stack_depth;
1461 #endif
1462 #endif
1463 
1464 #ifdef CONFIG_KMSAN
1465 	struct kmsan_ctx		kmsan_ctx;
1466 #endif
1467 
1468 #if IS_ENABLED(CONFIG_KUNIT)
1469 	struct kunit			*kunit_test;
1470 #endif
1471 
1472 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1473 	/* Index of current stored address in ret_stack: */
1474 	int				curr_ret_stack;
1475 	int				curr_ret_depth;
1476 
1477 	/* Stack of return addresses for return function tracing: */
1478 	unsigned long			*ret_stack;
1479 
1480 	/* Timestamp for last schedule: */
1481 	unsigned long long		ftrace_timestamp;
1482 	unsigned long long		ftrace_sleeptime;
1483 
1484 	/*
1485 	 * Number of functions that haven't been traced
1486 	 * because of depth overrun:
1487 	 */
1488 	atomic_t			trace_overrun;
1489 
1490 	/* Pause tracing: */
1491 	atomic_t			tracing_graph_pause;
1492 #endif
1493 
1494 #ifdef CONFIG_TRACING
1495 	/* Bitmask and counter of trace recursion: */
1496 	unsigned long			trace_recursion;
1497 #endif /* CONFIG_TRACING */
1498 
1499 #ifdef CONFIG_KCOV
1500 	/* See kernel/kcov.c for more details. */
1501 
1502 	/* Coverage collection mode enabled for this task (0 if disabled): */
1503 	unsigned int			kcov_mode;
1504 
1505 	/* Size of the kcov_area: */
1506 	unsigned int			kcov_size;
1507 
1508 	/* Buffer for coverage collection: */
1509 	void				*kcov_area;
1510 
1511 	/* KCOV descriptor wired with this task or NULL: */
1512 	struct kcov			*kcov;
1513 
1514 	/* KCOV common handle for remote coverage collection: */
1515 	u64				kcov_handle;
1516 
1517 	/* KCOV sequence number: */
1518 	int				kcov_sequence;
1519 
1520 	/* Collect coverage from softirq context: */
1521 	unsigned int			kcov_softirq;
1522 #endif
1523 
1524 #ifdef CONFIG_MEMCG_V1
1525 	struct mem_cgroup		*memcg_in_oom;
1526 #endif
1527 
1528 #ifdef CONFIG_MEMCG
1529 	/* Number of pages to reclaim on returning to userland: */
1530 	unsigned int			memcg_nr_pages_over_high;
1531 
1532 	/* Used by memcontrol for targeted memcg charge: */
1533 	struct mem_cgroup		*active_memcg;
1534 
1535 	/* Cache for current->cgroups->memcg->objcg lookups: */
1536 	struct obj_cgroup		*objcg;
1537 #endif
1538 
1539 #ifdef CONFIG_BLK_CGROUP
1540 	struct gendisk			*throttle_disk;
1541 #endif
1542 
1543 #ifdef CONFIG_UPROBES
1544 	struct uprobe_task		*utask;
1545 #endif
1546 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1547 	unsigned int			sequential_io;
1548 	unsigned int			sequential_io_avg;
1549 #endif
1550 	struct kmap_ctrl		kmap_ctrl;
1551 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1552 	unsigned long			task_state_change;
1553 # ifdef CONFIG_PREEMPT_RT
1554 	unsigned long			saved_state_change;
1555 # endif
1556 #endif
1557 	struct rcu_head			rcu;
1558 	refcount_t			rcu_users;
1559 	int				pagefault_disabled;
1560 #ifdef CONFIG_MMU
1561 	struct task_struct		*oom_reaper_list;
1562 	struct timer_list		oom_reaper_timer;
1563 #endif
1564 #ifdef CONFIG_VMAP_STACK
1565 	struct vm_struct		*stack_vm_area;
1566 #endif
1567 #ifdef CONFIG_THREAD_INFO_IN_TASK
1568 	/* A live task holds one reference: */
1569 	refcount_t			stack_refcount;
1570 #endif
1571 #ifdef CONFIG_LIVEPATCH
1572 	int patch_state;
1573 #endif
1574 #ifdef CONFIG_SECURITY
1575 	/* Used by LSM modules for access restriction: */
1576 	void				*security;
1577 #endif
1578 #ifdef CONFIG_BPF_SYSCALL
1579 	/* Used by BPF task local storage */
1580 	struct bpf_local_storage __rcu	*bpf_storage;
1581 	/* Used for BPF run context */
1582 	struct bpf_run_ctx		*bpf_ctx;
1583 #endif
1584 	/* Used by BPF for per-TASK xdp storage */
1585 	struct bpf_net_context		*bpf_net_context;
1586 
1587 #ifdef CONFIG_KSTACK_ERASE
1588 	unsigned long			lowest_stack;
1589 #endif
1590 #ifdef CONFIG_KSTACK_ERASE_METRICS
1591 	unsigned long			prev_lowest_stack;
1592 #endif
1593 
1594 #ifdef CONFIG_X86_MCE
1595 	void __user			*mce_vaddr;
1596 	__u64				mce_kflags;
1597 	u64				mce_addr;
1598 	__u64				mce_ripv : 1,
1599 					mce_whole_page : 1,
1600 					__mce_reserved : 62;
1601 	struct callback_head		mce_kill_me;
1602 	int				mce_count;
1603 #endif
1604 
1605 #ifdef CONFIG_KRETPROBES
1606 	struct llist_head               kretprobe_instances;
1607 #endif
1608 #ifdef CONFIG_RETHOOK
1609 	struct llist_head               rethooks;
1610 #endif
1611 
1612 #ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH
1613 	/*
1614 	 * If L1D flush is supported on mm context switch
1615 	 * then we use this callback head to queue kill work
1616 	 * to kill tasks that are not running on SMT disabled
1617 	 * cores
1618 	 */
1619 	struct callback_head		l1d_flush_kill;
1620 #endif
1621 
1622 #ifdef CONFIG_RV
1623 	/*
1624 	 * Per-task RV monitor, fixed in CONFIG_RV_PER_TASK_MONITORS.
1625 	 * If memory becomes a concern, we can think about a dynamic method.
1626 	 */
1627 	union rv_task_monitor		rv[CONFIG_RV_PER_TASK_MONITORS];
1628 #endif
1629 
1630 #ifdef CONFIG_USER_EVENTS
1631 	struct user_event_mm		*user_event_mm;
1632 #endif
1633 
1634 #ifdef CONFIG_UNWIND_USER
1635 	struct unwind_task_info		unwind_info;
1636 #endif
1637 
1638 	/* CPU-specific state of this task: */
1639 	struct thread_struct		thread;
1640 
1641 	/*
1642 	 * New fields for task_struct should be added above here, so that
1643 	 * they are included in the randomized portion of task_struct.
1644 	 */
1645 	randomized_struct_fields_end
1646 } __attribute__ ((aligned (64)));
1647 
1648 #ifdef CONFIG_SCHED_PROXY_EXEC
1649 DECLARE_STATIC_KEY_TRUE(__sched_proxy_exec);
1650 static inline bool sched_proxy_exec(void)
1651 {
1652 	return static_branch_likely(&__sched_proxy_exec);
1653 }
1654 #else
1655 static inline bool sched_proxy_exec(void)
1656 {
1657 	return false;
1658 }
1659 #endif
1660 
1661 #define TASK_REPORT_IDLE	(TASK_REPORT + 1)
1662 #define TASK_REPORT_MAX		(TASK_REPORT_IDLE << 1)
1663 
1664 static inline unsigned int __task_state_index(unsigned int tsk_state,
1665 					      unsigned int tsk_exit_state)
1666 {
1667 	unsigned int state = (tsk_state | tsk_exit_state) & TASK_REPORT;
1668 
1669 	BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);
1670 
1671 	if ((tsk_state & TASK_IDLE) == TASK_IDLE)
1672 		state = TASK_REPORT_IDLE;
1673 
1674 	/*
1675 	 * We're lying here, but rather than expose a completely new task state
1676 	 * to userspace, we can make this appear as if the task has gone through
1677 	 * a regular rt_mutex_lock() call.
1678 	 * Report frozen tasks as uninterruptible.
1679 	 */
1680 	if ((tsk_state & TASK_RTLOCK_WAIT) || (tsk_state & TASK_FROZEN))
1681 		state = TASK_UNINTERRUPTIBLE;
1682 
1683 	return fls(state);
1684 }
1685 
1686 static inline unsigned int task_state_index(struct task_struct *tsk)
1687 {
1688 	return __task_state_index(READ_ONCE(tsk->__state), tsk->exit_state);
1689 }
1690 
1691 static inline char task_index_to_char(unsigned int state)
1692 {
1693 	static const char state_char[] = "RSDTtXZPI";
1694 
1695 	BUILD_BUG_ON(TASK_REPORT_MAX * 2 != 1 << (sizeof(state_char) - 1));
1696 
1697 	return state_char[state];
1698 }
1699 
1700 static inline char task_state_to_char(struct task_struct *tsk)
1701 {
1702 	return task_index_to_char(task_state_index(tsk));
1703 }
1704 
1705 #ifdef CONFIG_ARCH_HAS_LAZY_MMU_MODE
1706 /**
1707  * __task_lazy_mmu_mode_active() - Test the lazy MMU mode state for a task.
1708  * @tsk: The task to check.
1709  *
1710  * Test whether @tsk has its lazy MMU mode state set to active (i.e. enabled
1711  * and not paused).
1712  *
1713  * This function only considers the state saved in task_struct; to test whether
1714  * current actually is in lazy MMU mode, is_lazy_mmu_mode_active() should be
1715  * used instead.
1716  *
1717  * This function is intended for architectures that implement the lazy MMU
1718  * mode; it must not be called from generic code.
1719  */
1720 static inline bool __task_lazy_mmu_mode_active(struct task_struct *tsk)
1721 {
1722 	struct lazy_mmu_state *state = &tsk->lazy_mmu_state;
1723 
1724 	return state->enable_count > 0 && state->pause_count == 0;
1725 }
1726 
1727 /**
1728  * is_lazy_mmu_mode_active() - Test whether we are currently in lazy MMU mode.
1729  *
1730  * Test whether the current context is in lazy MMU mode. This is true if both:
1731  * 1. We are not in interrupt context
1732  * 2. Lazy MMU mode is active for the current task
1733  *
1734  * This function is intended for architectures that implement the lazy MMU
1735  * mode; it must not be called from generic code.
1736  */
1737 static inline bool is_lazy_mmu_mode_active(void)
1738 {
1739 	if (in_interrupt())
1740 		return false;
1741 
1742 	return __task_lazy_mmu_mode_active(current);
1743 }
1744 #endif
1745 
1746 extern struct pid *cad_pid;
1747 
1748 /*
1749  * Per process flags
1750  */
1751 #define PF_VCPU			0x00000001	/* I'm a virtual CPU */
1752 #define PF_IDLE			0x00000002	/* I am an IDLE thread */
1753 #define PF_EXITING		0x00000004	/* Getting shut down */
1754 #define PF_POSTCOREDUMP		0x00000008	/* Coredumps should ignore this task */
1755 #define PF_IO_WORKER		0x00000010	/* Task is an IO worker */
1756 #define PF_WQ_WORKER		0x00000020	/* I'm a workqueue worker */
1757 #define PF_FORKNOEXEC		0x00000040	/* Forked but didn't exec */
1758 #define PF_MCE_PROCESS		0x00000080      /* Process policy on mce errors */
1759 #define PF_SUPERPRIV		0x00000100	/* Used super-user privileges */
1760 #define PF_DUMPCORE		0x00000200	/* Dumped core */
1761 #define PF_SIGNALED		0x00000400	/* Killed by a signal */
1762 #define PF_MEMALLOC		0x00000800	/* Allocating memory to free memory. See memalloc_noreclaim_save() */
1763 #define PF_NPROC_EXCEEDED	0x00001000	/* set_user() noticed that RLIMIT_NPROC was exceeded */
1764 #define PF_USED_MATH		0x00002000	/* If unset the fpu must be initialized before use */
1765 #define PF_USER_WORKER		0x00004000	/* Kernel thread cloned from userspace thread */
1766 #define PF_NOFREEZE		0x00008000	/* This thread should not be frozen */
1767 #define PF_KCOMPACTD		0x00010000	/* I am kcompactd */
1768 #define PF_KSWAPD		0x00020000	/* I am kswapd */
1769 #define PF_MEMALLOC_NOFS	0x00040000	/* All allocations inherit GFP_NOFS. See memalloc_nfs_save() */
1770 #define PF_MEMALLOC_NOIO	0x00080000	/* All allocations inherit GFP_NOIO. See memalloc_noio_save() */
1771 #define PF_LOCAL_THROTTLE	0x00100000	/* Throttle writes only against the bdi I write to,
1772 						 * I am cleaning dirty pages from some other bdi. */
1773 #define PF_KTHREAD		0x00200000	/* I am a kernel thread */
1774 #define PF_RANDOMIZE		0x00400000	/* Randomize virtual address space */
1775 #define PF__HOLE__00800000	0x00800000
1776 #define PF__HOLE__01000000	0x01000000
1777 #define PF__HOLE__02000000	0x02000000
1778 #define PF_NO_SETAFFINITY	0x04000000	/* Userland is not allowed to meddle with cpus_mask */
1779 #define PF_MCE_EARLY		0x08000000      /* Early kill for mce process policy */
1780 #define PF_MEMALLOC_PIN		0x10000000	/* Allocations constrained to zones which allow long term pinning.
1781 						 * See memalloc_pin_save() */
1782 #define PF_BLOCK_TS		0x20000000	/* plug has ts that needs updating */
1783 #define PF__HOLE__40000000	0x40000000
1784 #define PF_SUSPEND_TASK		0x80000000      /* This thread called freeze_processes() and should not be frozen */
1785 
1786 /*
1787  * Only the _current_ task can read/write to tsk->flags, but other
1788  * tasks can access tsk->flags in readonly mode for example
1789  * with tsk_used_math (like during threaded core dumping).
1790  * There is however an exception to this rule during ptrace
1791  * or during fork: the ptracer task is allowed to write to the
1792  * child->flags of its traced child (same goes for fork, the parent
1793  * can write to the child->flags), because we're guaranteed the
1794  * child is not running and in turn not changing child->flags
1795  * at the same time the parent does it.
1796  */
1797 #define clear_stopped_child_used_math(child)	do { (child)->flags &= ~PF_USED_MATH; } while (0)
1798 #define set_stopped_child_used_math(child)	do { (child)->flags |= PF_USED_MATH; } while (0)
1799 #define clear_used_math()			clear_stopped_child_used_math(current)
1800 #define set_used_math()				set_stopped_child_used_math(current)
1801 
1802 #define conditional_stopped_child_used_math(condition, child) \
1803 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1804 
1805 #define conditional_used_math(condition)	conditional_stopped_child_used_math(condition, current)
1806 
1807 #define copy_to_stopped_child_used_math(child) \
1808 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1809 
1810 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1811 #define tsk_used_math(p)			((p)->flags & PF_USED_MATH)
1812 #define used_math()				tsk_used_math(current)
1813 
1814 static __always_inline bool is_percpu_thread(void)
1815 {
1816 	return (current->flags & PF_NO_SETAFFINITY) &&
1817 		(current->nr_cpus_allowed  == 1);
1818 }
1819 
1820 static __always_inline bool is_user_task(struct task_struct *task)
1821 {
1822 	return task->mm && !(task->flags & (PF_KTHREAD | PF_USER_WORKER));
1823 }
1824 
1825 /* Per-process atomic flags. */
1826 #define PFA_NO_NEW_PRIVS		0	/* May not gain new privileges. */
1827 #define PFA_SPREAD_PAGE			1	/* Spread page cache over cpuset */
1828 #define PFA_SPREAD_SLAB			2	/* Spread some slab caches over cpuset */
1829 #define PFA_SPEC_SSB_DISABLE		3	/* Speculative Store Bypass disabled */
1830 #define PFA_SPEC_SSB_FORCE_DISABLE	4	/* Speculative Store Bypass force disabled*/
1831 #define PFA_SPEC_IB_DISABLE		5	/* Indirect branch speculation restricted */
1832 #define PFA_SPEC_IB_FORCE_DISABLE	6	/* Indirect branch speculation permanently restricted */
1833 #define PFA_SPEC_SSB_NOEXEC		7	/* Speculative Store Bypass clear on execve() */
1834 
1835 #define TASK_PFA_TEST(name, func)					\
1836 	static inline bool task_##func(struct task_struct *p)		\
1837 	{ return test_bit(PFA_##name, &p->atomic_flags); }
1838 
1839 #define TASK_PFA_SET(name, func)					\
1840 	static inline void task_set_##func(struct task_struct *p)	\
1841 	{ set_bit(PFA_##name, &p->atomic_flags); }
1842 
1843 #define TASK_PFA_CLEAR(name, func)					\
1844 	static inline void task_clear_##func(struct task_struct *p)	\
1845 	{ clear_bit(PFA_##name, &p->atomic_flags); }
1846 
1847 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1848 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1849 
1850 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1851 TASK_PFA_SET(SPREAD_PAGE, spread_page)
1852 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
1853 
1854 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
1855 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
1856 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1857 
1858 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable)
1859 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable)
1860 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable)
1861 
1862 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1863 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1864 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1865 
1866 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1867 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1868 
1869 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable)
1870 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable)
1871 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable)
1872 
1873 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1874 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1875 
1876 static inline void
1877 current_restore_flags(unsigned long orig_flags, unsigned long flags)
1878 {
1879 	current->flags &= ~flags;
1880 	current->flags |= orig_flags & flags;
1881 }
1882 
1883 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
1884 extern int task_can_attach(struct task_struct *p);
1885 extern int dl_bw_alloc(int cpu, u64 dl_bw);
1886 extern void dl_bw_free(int cpu, u64 dl_bw);
1887 
1888 /* set_cpus_allowed_force() - consider using set_cpus_allowed_ptr() instead */
1889 extern void set_cpus_allowed_force(struct task_struct *p, const struct cpumask *new_mask);
1890 
1891 /**
1892  * set_cpus_allowed_ptr - set CPU affinity mask of a task
1893  * @p: the task
1894  * @new_mask: CPU affinity mask
1895  *
1896  * Return: zero if successful, or a negative error code
1897  */
1898 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
1899 extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node);
1900 extern void release_user_cpus_ptr(struct task_struct *p);
1901 extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask);
1902 extern void force_compatible_cpus_allowed_ptr(struct task_struct *p);
1903 extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p);
1904 
1905 extern int yield_to(struct task_struct *p, bool preempt);
1906 extern void set_user_nice(struct task_struct *p, long nice);
1907 extern int task_prio(const struct task_struct *p);
1908 
1909 /**
1910  * task_nice - return the nice value of a given task.
1911  * @p: the task in question.
1912  *
1913  * Return: The nice value [ -20 ... 0 ... 19 ].
1914  */
1915 static inline int task_nice(const struct task_struct *p)
1916 {
1917 	return PRIO_TO_NICE((p)->static_prio);
1918 }
1919 
1920 extern int can_nice(const struct task_struct *p, const int nice);
1921 extern int task_curr(const struct task_struct *p);
1922 extern int idle_cpu(int cpu);
1923 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
1924 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
1925 extern void sched_set_fifo(struct task_struct *p);
1926 extern void sched_set_fifo_low(struct task_struct *p);
1927 extern void sched_set_fifo_secondary(struct task_struct *p);
1928 extern void sched_set_normal(struct task_struct *p, int nice);
1929 extern int sched_setattr(struct task_struct *, const struct sched_attr *);
1930 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *);
1931 extern struct task_struct *idle_task(int cpu);
1932 
1933 /**
1934  * is_idle_task - is the specified task an idle task?
1935  * @p: the task in question.
1936  *
1937  * Return: 1 if @p is an idle task. 0 otherwise.
1938  */
1939 static __always_inline bool is_idle_task(const struct task_struct *p)
1940 {
1941 	return !!(p->flags & PF_IDLE);
1942 }
1943 
1944 extern struct task_struct *curr_task(int cpu);
1945 extern void ia64_set_curr_task(int cpu, struct task_struct *p);
1946 
1947 void yield(void);
1948 
1949 union thread_union {
1950 	struct task_struct task;
1951 #ifndef CONFIG_THREAD_INFO_IN_TASK
1952 	struct thread_info thread_info;
1953 #endif
1954 	unsigned long stack[THREAD_SIZE/sizeof(long)];
1955 };
1956 
1957 #ifndef CONFIG_THREAD_INFO_IN_TASK
1958 extern struct thread_info init_thread_info;
1959 #endif
1960 
1961 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];
1962 
1963 #ifdef CONFIG_THREAD_INFO_IN_TASK
1964 # define task_thread_info(task)	(&(task)->thread_info)
1965 #else
1966 # define task_thread_info(task)	((struct thread_info *)(task)->stack)
1967 #endif
1968 
1969 /*
1970  * find a task by one of its numerical ids
1971  *
1972  * find_task_by_pid_ns():
1973  *      finds a task by its pid in the specified namespace
1974  * find_task_by_vpid():
1975  *      finds a task by its virtual pid
1976  *
1977  * see also find_vpid() etc in include/linux/pid.h
1978  */
1979 
1980 extern struct task_struct *find_task_by_vpid(pid_t nr);
1981 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns);
1982 
1983 /*
1984  * find a task by its virtual pid and get the task struct
1985  */
1986 extern struct task_struct *find_get_task_by_vpid(pid_t nr);
1987 
1988 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1989 extern int wake_up_process(struct task_struct *tsk);
1990 extern void wake_up_new_task(struct task_struct *tsk);
1991 
1992 extern void kick_process(struct task_struct *tsk);
1993 
1994 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
1995 #define set_task_comm(tsk, from) ({			\
1996 	BUILD_BUG_ON(sizeof(from) != TASK_COMM_LEN);	\
1997 	__set_task_comm(tsk, from, false);		\
1998 })
1999 
2000 /*
2001  * - Why not use task_lock()?
2002  *   User space can randomly change their names anyway, so locking for readers
2003  *   doesn't make sense. For writers, locking is probably necessary, as a race
2004  *   condition could lead to long-term mixed results.
2005  *   The strscpy_pad() in __set_task_comm() can ensure that the task comm is
2006  *   always NUL-terminated and zero-padded. Therefore the race condition between
2007  *   reader and writer is not an issue.
2008  *
2009  * - BUILD_BUG_ON() can help prevent the buf from being truncated.
2010  *   Since the callers don't perform any return value checks, this safeguard is
2011  *   necessary.
2012  */
2013 #define get_task_comm(buf, tsk) ({			\
2014 	BUILD_BUG_ON(sizeof(buf) < TASK_COMM_LEN);	\
2015 	strscpy_pad(buf, (tsk)->comm);			\
2016 	buf;						\
2017 })
2018 
2019 static __always_inline void scheduler_ipi(void)
2020 {
2021 	/*
2022 	 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting
2023 	 * TIF_NEED_RESCHED remotely (for the first time) will also send
2024 	 * this IPI.
2025 	 */
2026 	preempt_fold_need_resched();
2027 }
2028 
2029 extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state);
2030 
2031 /*
2032  * Set thread flags in other task's structures.
2033  * See asm/thread_info.h for TIF_xxxx flags available:
2034  */
2035 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2036 {
2037 	set_ti_thread_flag(task_thread_info(tsk), flag);
2038 }
2039 
2040 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2041 {
2042 	clear_ti_thread_flag(task_thread_info(tsk), flag);
2043 }
2044 
2045 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag,
2046 					  bool value)
2047 {
2048 	update_ti_thread_flag(task_thread_info(tsk), flag, value);
2049 }
2050 
2051 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2052 {
2053 	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2054 }
2055 
2056 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2057 {
2058 	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2059 }
2060 
2061 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2062 {
2063 	return test_ti_thread_flag(task_thread_info(tsk), flag);
2064 }
2065 
2066 static inline void set_tsk_need_resched(struct task_struct *tsk)
2067 {
2068 	if (tracepoint_enabled(sched_set_need_resched_tp) &&
2069 	    !test_tsk_thread_flag(tsk, TIF_NEED_RESCHED))
2070 		__trace_set_need_resched(tsk, TIF_NEED_RESCHED);
2071 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2072 }
2073 
2074 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2075 {
2076 	atomic_long_andnot(_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY,
2077 			   (atomic_long_t *)&task_thread_info(tsk)->flags);
2078 }
2079 
2080 static inline int test_tsk_need_resched(struct task_struct *tsk)
2081 {
2082 	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2083 }
2084 
2085 static inline void set_need_resched_current(void)
2086 {
2087 	lockdep_assert_irqs_disabled();
2088 	set_tsk_need_resched(current);
2089 	set_preempt_need_resched();
2090 }
2091 
2092 /*
2093  * cond_resched() and cond_resched_lock(): latency reduction via
2094  * explicit rescheduling in places that are safe. The return
2095  * value indicates whether a reschedule was done in fact.
2096  * cond_resched_lock() will drop the spinlock before scheduling,
2097  */
2098 #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC)
2099 extern int __cond_resched(void);
2100 
2101 #if defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL)
2102 
2103 DECLARE_STATIC_CALL(cond_resched, __cond_resched);
2104 
2105 static __always_inline int _cond_resched(void)
2106 {
2107 	return static_call_mod(cond_resched)();
2108 }
2109 
2110 #elif defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY)
2111 
2112 extern int dynamic_cond_resched(void);
2113 
2114 static __always_inline int _cond_resched(void)
2115 {
2116 	return dynamic_cond_resched();
2117 }
2118 
2119 #else /* !CONFIG_PREEMPTION */
2120 
2121 static inline int _cond_resched(void)
2122 {
2123 	return __cond_resched();
2124 }
2125 
2126 #endif /* PREEMPT_DYNAMIC && CONFIG_HAVE_PREEMPT_DYNAMIC_CALL */
2127 
2128 #else /* CONFIG_PREEMPTION && !CONFIG_PREEMPT_DYNAMIC */
2129 
2130 static inline int _cond_resched(void)
2131 {
2132 	return 0;
2133 }
2134 
2135 #endif /* !CONFIG_PREEMPTION || CONFIG_PREEMPT_DYNAMIC */
2136 
2137 #define cond_resched() ({			\
2138 	__might_resched(__FILE__, __LINE__, 0);	\
2139 	_cond_resched();			\
2140 })
2141 
2142 extern int __cond_resched_lock(spinlock_t *lock) __must_hold(lock);
2143 extern int __cond_resched_rwlock_read(rwlock_t *lock) __must_hold_shared(lock);
2144 extern int __cond_resched_rwlock_write(rwlock_t *lock) __must_hold(lock);
2145 
2146 #define MIGHT_RESCHED_RCU_SHIFT		8
2147 #define MIGHT_RESCHED_PREEMPT_MASK	((1U << MIGHT_RESCHED_RCU_SHIFT) - 1)
2148 
2149 #ifndef CONFIG_PREEMPT_RT
2150 /*
2151  * Non RT kernels have an elevated preempt count due to the held lock,
2152  * but are not allowed to be inside a RCU read side critical section
2153  */
2154 # define PREEMPT_LOCK_RESCHED_OFFSETS	PREEMPT_LOCK_OFFSET
2155 #else
2156 /*
2157  * spin/rw_lock() on RT implies rcu_read_lock(). The might_sleep() check in
2158  * cond_resched*lock() has to take that into account because it checks for
2159  * preempt_count() and rcu_preempt_depth().
2160  */
2161 # define PREEMPT_LOCK_RESCHED_OFFSETS	\
2162 	(PREEMPT_LOCK_OFFSET + (1U << MIGHT_RESCHED_RCU_SHIFT))
2163 #endif
2164 
2165 #define cond_resched_lock(lock) ({						\
2166 	__might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS);	\
2167 	__cond_resched_lock(lock);						\
2168 })
2169 
2170 #define cond_resched_rwlock_read(lock) ({					\
2171 	__might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS);	\
2172 	__cond_resched_rwlock_read(lock);					\
2173 })
2174 
2175 #define cond_resched_rwlock_write(lock) ({					\
2176 	__might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS);	\
2177 	__cond_resched_rwlock_write(lock);					\
2178 })
2179 
2180 #ifndef CONFIG_PREEMPT_RT
2181 static inline struct mutex *__get_task_blocked_on(struct task_struct *p)
2182 {
2183 	struct mutex *m = p->blocked_on;
2184 
2185 	if (m)
2186 		lockdep_assert_held_once(&m->wait_lock);
2187 	return m;
2188 }
2189 
2190 static inline void __set_task_blocked_on(struct task_struct *p, struct mutex *m)
2191 {
2192 	struct mutex *blocked_on = READ_ONCE(p->blocked_on);
2193 
2194 	WARN_ON_ONCE(!m);
2195 	/* The task should only be setting itself as blocked */
2196 	WARN_ON_ONCE(p != current);
2197 	/* Currently we serialize blocked_on under the mutex::wait_lock */
2198 	lockdep_assert_held_once(&m->wait_lock);
2199 	/*
2200 	 * Check ensure we don't overwrite existing mutex value
2201 	 * with a different mutex. Note, setting it to the same
2202 	 * lock repeatedly is ok.
2203 	 */
2204 	WARN_ON_ONCE(blocked_on && blocked_on != m);
2205 	WRITE_ONCE(p->blocked_on, m);
2206 }
2207 
2208 static inline void set_task_blocked_on(struct task_struct *p, struct mutex *m)
2209 {
2210 	guard(raw_spinlock_irqsave)(&m->wait_lock);
2211 	__set_task_blocked_on(p, m);
2212 }
2213 
2214 static inline void __clear_task_blocked_on(struct task_struct *p, struct mutex *m)
2215 {
2216 	if (m) {
2217 		struct mutex *blocked_on = READ_ONCE(p->blocked_on);
2218 
2219 		/* Currently we serialize blocked_on under the mutex::wait_lock */
2220 		lockdep_assert_held_once(&m->wait_lock);
2221 		/*
2222 		 * There may be cases where we re-clear already cleared
2223 		 * blocked_on relationships, but make sure we are not
2224 		 * clearing the relationship with a different lock.
2225 		 */
2226 		WARN_ON_ONCE(blocked_on && blocked_on != m);
2227 	}
2228 	WRITE_ONCE(p->blocked_on, NULL);
2229 }
2230 
2231 static inline void clear_task_blocked_on(struct task_struct *p, struct mutex *m)
2232 {
2233 	guard(raw_spinlock_irqsave)(&m->wait_lock);
2234 	__clear_task_blocked_on(p, m);
2235 }
2236 #else
2237 static inline void __clear_task_blocked_on(struct task_struct *p, struct rt_mutex *m)
2238 {
2239 }
2240 
2241 static inline void clear_task_blocked_on(struct task_struct *p, struct rt_mutex *m)
2242 {
2243 }
2244 #endif /* !CONFIG_PREEMPT_RT */
2245 
2246 static __always_inline bool need_resched(void)
2247 {
2248 	return unlikely(tif_need_resched());
2249 }
2250 
2251 /*
2252  * Wrappers for p->thread_info->cpu access. No-op on UP.
2253  */
2254 #ifdef CONFIG_SMP
2255 
2256 static inline unsigned int task_cpu(const struct task_struct *p)
2257 {
2258 	return READ_ONCE(task_thread_info(p)->cpu);
2259 }
2260 
2261 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2262 
2263 #else
2264 
2265 static inline unsigned int task_cpu(const struct task_struct *p)
2266 {
2267 	return 0;
2268 }
2269 
2270 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2271 {
2272 }
2273 
2274 #endif /* CONFIG_SMP */
2275 
2276 static inline bool task_is_runnable(struct task_struct *p)
2277 {
2278 	return p->on_rq && !p->se.sched_delayed;
2279 }
2280 
2281 extern bool sched_task_on_rq(struct task_struct *p);
2282 extern unsigned long get_wchan(struct task_struct *p);
2283 extern struct task_struct *cpu_curr_snapshot(int cpu);
2284 
2285 /*
2286  * In order to reduce various lock holder preemption latencies provide an
2287  * interface to see if a vCPU is currently running or not.
2288  *
2289  * This allows us to terminate optimistic spin loops and block, analogous to
2290  * the native optimistic spin heuristic of testing if the lock owner task is
2291  * running or not.
2292  */
2293 #ifndef vcpu_is_preempted
2294 static inline bool vcpu_is_preempted(int cpu)
2295 {
2296 	return false;
2297 }
2298 #endif
2299 
2300 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2301 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2302 
2303 #ifndef TASK_SIZE_OF
2304 #define TASK_SIZE_OF(tsk)	TASK_SIZE
2305 #endif
2306 
2307 static inline bool owner_on_cpu(struct task_struct *owner)
2308 {
2309 	/*
2310 	 * As lock holder preemption issue, we both skip spinning if
2311 	 * task is not on cpu or its cpu is preempted
2312 	 */
2313 	return READ_ONCE(owner->on_cpu) && !vcpu_is_preempted(task_cpu(owner));
2314 }
2315 
2316 /* Returns effective CPU energy utilization, as seen by the scheduler */
2317 unsigned long sched_cpu_util(int cpu);
2318 
2319 #ifdef CONFIG_SCHED_CORE
2320 extern void sched_core_free(struct task_struct *tsk);
2321 extern void sched_core_fork(struct task_struct *p);
2322 extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type,
2323 				unsigned long uaddr);
2324 extern int sched_core_idle_cpu(int cpu);
2325 #else
2326 static inline void sched_core_free(struct task_struct *tsk) { }
2327 static inline void sched_core_fork(struct task_struct *p) { }
2328 static inline int sched_core_idle_cpu(int cpu) { return idle_cpu(cpu); }
2329 #endif
2330 
2331 extern void sched_set_stop_task(int cpu, struct task_struct *stop);
2332 
2333 #ifdef CONFIG_MEM_ALLOC_PROFILING
2334 static __always_inline struct alloc_tag *alloc_tag_save(struct alloc_tag *tag)
2335 {
2336 	swap(current->alloc_tag, tag);
2337 	return tag;
2338 }
2339 
2340 static __always_inline void alloc_tag_restore(struct alloc_tag *tag, struct alloc_tag *old)
2341 {
2342 #ifdef CONFIG_MEM_ALLOC_PROFILING_DEBUG
2343 	WARN(current->alloc_tag != tag, "current->alloc_tag was changed:\n");
2344 #endif
2345 	current->alloc_tag = old;
2346 }
2347 #else
2348 #define alloc_tag_save(_tag)			NULL
2349 #define alloc_tag_restore(_tag, _old)		do {} while (0)
2350 #endif
2351 
2352 /* Avoids recursive inclusion hell */
2353 #ifdef CONFIG_SCHED_MM_CID
2354 void sched_mm_cid_before_execve(struct task_struct *t);
2355 void sched_mm_cid_after_execve(struct task_struct *t);
2356 void sched_mm_cid_fork(struct task_struct *t);
2357 void sched_mm_cid_exit(struct task_struct *t);
2358 static __always_inline int task_mm_cid(struct task_struct *t)
2359 {
2360 	return t->mm_cid.cid & ~(MM_CID_ONCPU | MM_CID_TRANSIT);
2361 }
2362 #else
2363 static inline void sched_mm_cid_before_execve(struct task_struct *t) { }
2364 static inline void sched_mm_cid_after_execve(struct task_struct *t) { }
2365 static inline void sched_mm_cid_fork(struct task_struct *t) { }
2366 static inline void sched_mm_cid_exit(struct task_struct *t) { }
2367 static __always_inline int task_mm_cid(struct task_struct *t)
2368 {
2369 	/*
2370 	 * Use the processor id as a fall-back when the mm cid feature is
2371 	 * disabled. This provides functional per-cpu data structure accesses
2372 	 * in user-space, althrough it won't provide the memory usage benefits.
2373 	 */
2374 	return task_cpu(t);
2375 }
2376 #endif
2377 
2378 #ifndef MODULE
2379 #ifndef COMPILE_OFFSETS
2380 
2381 extern void ___migrate_enable(void);
2382 
2383 struct rq;
2384 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
2385 
2386 /*
2387  * The "struct rq" is not available here, so we can't access the
2388  * "runqueues" with this_cpu_ptr(), as the compilation will fail in
2389  * this_cpu_ptr() -> raw_cpu_ptr() -> __verify_pcpu_ptr():
2390  *   typeof((ptr) + 0)
2391  *
2392  * So use arch_raw_cpu_ptr()/PERCPU_PTR() directly here.
2393  */
2394 #ifdef CONFIG_SMP
2395 #define this_rq_raw() arch_raw_cpu_ptr(&runqueues)
2396 #else
2397 #define this_rq_raw() PERCPU_PTR(&runqueues)
2398 #endif
2399 #define this_rq_pinned() (*(unsigned int *)((void *)this_rq_raw() + RQ_nr_pinned))
2400 
2401 static inline void __migrate_enable(void)
2402 {
2403 	struct task_struct *p = current;
2404 
2405 #ifdef CONFIG_DEBUG_PREEMPT
2406 	/*
2407 	 * Check both overflow from migrate_disable() and superfluous
2408 	 * migrate_enable().
2409 	 */
2410 	if (WARN_ON_ONCE((s16)p->migration_disabled <= 0))
2411 		return;
2412 #endif
2413 
2414 	if (p->migration_disabled > 1) {
2415 		p->migration_disabled--;
2416 		return;
2417 	}
2418 
2419 	/*
2420 	 * Ensure stop_task runs either before or after this, and that
2421 	 * __set_cpus_allowed_ptr(SCA_MIGRATE_ENABLE) doesn't schedule().
2422 	 */
2423 	guard(preempt)();
2424 	if (unlikely(p->cpus_ptr != &p->cpus_mask))
2425 		___migrate_enable();
2426 	/*
2427 	 * Mustn't clear migration_disabled() until cpus_ptr points back at the
2428 	 * regular cpus_mask, otherwise things that race (eg.
2429 	 * select_fallback_rq) get confused.
2430 	 */
2431 	barrier();
2432 	p->migration_disabled = 0;
2433 	this_rq_pinned()--;
2434 }
2435 
2436 static inline void __migrate_disable(void)
2437 {
2438 	struct task_struct *p = current;
2439 
2440 	if (p->migration_disabled) {
2441 #ifdef CONFIG_DEBUG_PREEMPT
2442 		/*
2443 		 *Warn about overflow half-way through the range.
2444 		 */
2445 		WARN_ON_ONCE((s16)p->migration_disabled < 0);
2446 #endif
2447 		p->migration_disabled++;
2448 		return;
2449 	}
2450 
2451 	guard(preempt)();
2452 	this_rq_pinned()++;
2453 	p->migration_disabled = 1;
2454 }
2455 #else /* !COMPILE_OFFSETS */
2456 static inline void __migrate_disable(void) { }
2457 static inline void __migrate_enable(void) { }
2458 #endif /* !COMPILE_OFFSETS */
2459 
2460 /*
2461  * So that it is possible to not export the runqueues variable, define and
2462  * export migrate_enable/migrate_disable in kernel/sched/core.c too, and use
2463  * them for the modules. The macro "INSTANTIATE_EXPORTED_MIGRATE_DISABLE" will
2464  * be defined in kernel/sched/core.c.
2465  */
2466 #ifndef INSTANTIATE_EXPORTED_MIGRATE_DISABLE
2467 static __always_inline void migrate_disable(void)
2468 {
2469 	__migrate_disable();
2470 }
2471 
2472 static __always_inline void migrate_enable(void)
2473 {
2474 	__migrate_enable();
2475 }
2476 #else /* INSTANTIATE_EXPORTED_MIGRATE_DISABLE */
2477 extern void migrate_disable(void);
2478 extern void migrate_enable(void);
2479 #endif /* INSTANTIATE_EXPORTED_MIGRATE_DISABLE */
2480 
2481 #else /* MODULE */
2482 extern void migrate_disable(void);
2483 extern void migrate_enable(void);
2484 #endif /* MODULE */
2485 
2486 DEFINE_LOCK_GUARD_0(migrate, migrate_disable(), migrate_enable())
2487 
2488 #endif
2489