xref: /linux/include/linux/sched.h (revision 61706251492eff650e91c58507bc77e1a12c7fbb)
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 	u64				max_slice;
583 
584 	struct list_head		group_node;
585 	unsigned char			on_rq;
586 	unsigned char			sched_delayed;
587 	unsigned char			rel_deadline;
588 	unsigned char			custom_slice;
589 					/* hole */
590 
591 	u64				exec_start;
592 	u64				sum_exec_runtime;
593 	u64				prev_sum_exec_runtime;
594 	u64				vruntime;
595 	/* Approximated virtual lag: */
596 	s64				vlag;
597 	/* 'Protected' deadline, to give out minimum quantums: */
598 	u64				vprot;
599 	u64				slice;
600 
601 	u64				nr_migrations;
602 
603 #ifdef CONFIG_FAIR_GROUP_SCHED
604 	int				depth;
605 	struct sched_entity		*parent;
606 	/* rq on which this entity is (to be) queued: */
607 	struct cfs_rq			*cfs_rq;
608 	/* rq "owned" by this entity/group: */
609 	struct cfs_rq			*my_q;
610 	/* cached value of my_q->h_nr_running */
611 	unsigned long			runnable_weight;
612 #endif
613 
614 	/*
615 	 * Per entity load average tracking.
616 	 *
617 	 * Put into separate cache line so it does not
618 	 * collide with read-mostly values above.
619 	 */
620 	struct sched_avg		avg;
621 };
622 
623 struct sched_rt_entity {
624 	struct list_head		run_list;
625 	unsigned long			timeout;
626 	unsigned long			watchdog_stamp;
627 	unsigned int			time_slice;
628 	unsigned short			on_rq;
629 	unsigned short			on_list;
630 
631 	struct sched_rt_entity		*back;
632 #ifdef CONFIG_RT_GROUP_SCHED
633 	struct sched_rt_entity		*parent;
634 	/* rq on which this entity is (to be) queued: */
635 	struct rt_rq			*rt_rq;
636 	/* rq "owned" by this entity/group: */
637 	struct rt_rq			*my_q;
638 #endif
639 } __randomize_layout;
640 
641 struct rq_flags;
642 typedef struct task_struct *(*dl_server_pick_f)(struct sched_dl_entity *, struct rq_flags *rf);
643 
644 struct sched_dl_entity {
645 	struct rb_node			rb_node;
646 
647 	/*
648 	 * Original scheduling parameters. Copied here from sched_attr
649 	 * during sched_setattr(), they will remain the same until
650 	 * the next sched_setattr().
651 	 */
652 	u64				dl_runtime;	/* Maximum runtime for each instance	*/
653 	u64				dl_deadline;	/* Relative deadline of each instance	*/
654 	u64				dl_period;	/* Separation of two instances (period) */
655 	u64				dl_bw;		/* dl_runtime / dl_period		*/
656 	u64				dl_density;	/* dl_runtime / dl_deadline		*/
657 
658 	/*
659 	 * Actual scheduling parameters. Initialized with the values above,
660 	 * they are continuously updated during task execution. Note that
661 	 * the remaining runtime could be < 0 in case we are in overrun.
662 	 */
663 	s64				runtime;	/* Remaining runtime for this instance	*/
664 	u64				deadline;	/* Absolute deadline for this instance	*/
665 	unsigned int			flags;		/* Specifying the scheduler behaviour	*/
666 
667 	/*
668 	 * Some bool flags:
669 	 *
670 	 * @dl_throttled tells if we exhausted the runtime. If so, the
671 	 * task has to wait for a replenishment to be performed at the
672 	 * next firing of dl_timer.
673 	 *
674 	 * @dl_yielded tells if task gave up the CPU before consuming
675 	 * all its available runtime during the last job.
676 	 *
677 	 * @dl_non_contending tells if the task is inactive while still
678 	 * contributing to the active utilization. In other words, it
679 	 * indicates if the inactive timer has been armed and its handler
680 	 * has not been executed yet. This flag is useful to avoid race
681 	 * conditions between the inactive timer handler and the wakeup
682 	 * code.
683 	 *
684 	 * @dl_overrun tells if the task asked to be informed about runtime
685 	 * overruns.
686 	 *
687 	 * @dl_server tells if this is a server entity.
688 	 *
689 	 * @dl_server_active tells if the dlserver is active(started).
690 	 * dlserver is started on first cfs enqueue on an idle runqueue
691 	 * and is stopped when a dequeue results in 0 cfs tasks on the
692 	 * runqueue. In other words, dlserver is active only when cpu's
693 	 * runqueue has atleast one cfs task.
694 	 *
695 	 * @dl_defer tells if this is a deferred or regular server. For
696 	 * now only defer server exists.
697 	 *
698 	 * @dl_defer_armed tells if the deferrable server is waiting
699 	 * for the replenishment timer to activate it.
700 	 *
701 	 * @dl_defer_running tells if the deferrable server is actually
702 	 * running, skipping the defer phase.
703 	 *
704 	 * @dl_defer_idle tracks idle state
705 	 */
706 	unsigned int			dl_throttled      : 1;
707 	unsigned int			dl_yielded        : 1;
708 	unsigned int			dl_non_contending : 1;
709 	unsigned int			dl_overrun	  : 1;
710 	unsigned int			dl_server         : 1;
711 	unsigned int			dl_server_active  : 1;
712 	unsigned int			dl_defer	  : 1;
713 	unsigned int			dl_defer_armed	  : 1;
714 	unsigned int			dl_defer_running  : 1;
715 	unsigned int			dl_defer_idle     : 1;
716 
717 	/*
718 	 * Bandwidth enforcement timer. Each -deadline task has its
719 	 * own bandwidth to be enforced, thus we need one timer per task.
720 	 */
721 	struct hrtimer			dl_timer;
722 
723 	/*
724 	 * Inactive timer, responsible for decreasing the active utilization
725 	 * at the "0-lag time". When a -deadline task blocks, it contributes
726 	 * to GRUB's active utilization until the "0-lag time", hence a
727 	 * timer is needed to decrease the active utilization at the correct
728 	 * time.
729 	 */
730 	struct hrtimer			inactive_timer;
731 
732 	/*
733 	 * Bits for DL-server functionality. Also see the comment near
734 	 * dl_server_update().
735 	 *
736 	 * @rq the runqueue this server is for
737 	 */
738 	struct rq			*rq;
739 	dl_server_pick_f		server_pick_task;
740 
741 #ifdef CONFIG_RT_MUTEXES
742 	/*
743 	 * Priority Inheritance. When a DEADLINE scheduling entity is boosted
744 	 * pi_se points to the donor, otherwise points to the dl_se it belongs
745 	 * to (the original one/itself).
746 	 */
747 	struct sched_dl_entity *pi_se;
748 #endif
749 };
750 
751 #ifdef CONFIG_UCLAMP_TASK
752 /* Number of utilization clamp buckets (shorter alias) */
753 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT
754 
755 /*
756  * Utilization clamp for a scheduling entity
757  * @value:		clamp value "assigned" to a se
758  * @bucket_id:		bucket index corresponding to the "assigned" value
759  * @active:		the se is currently refcounted in a rq's bucket
760  * @user_defined:	the requested clamp value comes from user-space
761  *
762  * The bucket_id is the index of the clamp bucket matching the clamp value
763  * which is pre-computed and stored to avoid expensive integer divisions from
764  * the fast path.
765  *
766  * The active bit is set whenever a task has got an "effective" value assigned,
767  * which can be different from the clamp value "requested" from user-space.
768  * This allows to know a task is refcounted in the rq's bucket corresponding
769  * to the "effective" bucket_id.
770  *
771  * The user_defined bit is set whenever a task has got a task-specific clamp
772  * value requested from userspace, i.e. the system defaults apply to this task
773  * just as a restriction. This allows to relax default clamps when a less
774  * restrictive task-specific value has been requested, thus allowing to
775  * implement a "nice" semantic. For example, a task running with a 20%
776  * default boost can still drop its own boosting to 0%.
777  */
778 struct uclamp_se {
779 	unsigned int value		: bits_per(SCHED_CAPACITY_SCALE);
780 	unsigned int bucket_id		: bits_per(UCLAMP_BUCKETS);
781 	unsigned int active		: 1;
782 	unsigned int user_defined	: 1;
783 };
784 #endif /* CONFIG_UCLAMP_TASK */
785 
786 union rcu_special {
787 	struct {
788 		u8			blocked;
789 		u8			need_qs;
790 		u8			exp_hint; /* Hint for performance. */
791 		u8			need_mb; /* Readers need smp_mb(). */
792 	} b; /* Bits. */
793 	u32 s; /* Set of bits. */
794 };
795 
796 enum perf_event_task_context {
797 	perf_invalid_context = -1,
798 	perf_hw_context = 0,
799 	perf_sw_context,
800 	perf_nr_task_contexts,
801 };
802 
803 /*
804  * Number of contexts where an event can trigger:
805  *      task, softirq, hardirq, nmi.
806  */
807 #define PERF_NR_CONTEXTS	4
808 
809 struct wake_q_node {
810 	struct wake_q_node *next;
811 };
812 
813 struct kmap_ctrl {
814 #ifdef CONFIG_KMAP_LOCAL
815 	int				idx;
816 	pte_t				pteval[KM_MAX_IDX];
817 #endif
818 };
819 
820 struct task_struct {
821 #ifdef CONFIG_THREAD_INFO_IN_TASK
822 	/*
823 	 * For reasons of header soup (see current_thread_info()), this
824 	 * must be the first element of task_struct.
825 	 */
826 	struct thread_info		thread_info;
827 #endif
828 	unsigned int			__state;
829 
830 	/* saved state for "spinlock sleepers" */
831 	unsigned int			saved_state;
832 
833 	/*
834 	 * This begins the randomizable portion of task_struct. Only
835 	 * scheduling-critical items should be added above here.
836 	 */
837 	randomized_struct_fields_start
838 
839 	void				*stack;
840 	refcount_t			usage;
841 	/* Per task flags (PF_*), defined further below: */
842 	unsigned int			flags;
843 	unsigned int			ptrace;
844 
845 #ifdef CONFIG_MEM_ALLOC_PROFILING
846 	struct alloc_tag		*alloc_tag;
847 #endif
848 
849 	int				on_cpu;
850 	struct __call_single_node	wake_entry;
851 	unsigned int			wakee_flips;
852 	unsigned long			wakee_flip_decay_ts;
853 	struct task_struct		*last_wakee;
854 
855 	/*
856 	 * recent_used_cpu is initially set as the last CPU used by a task
857 	 * that wakes affine another task. Waker/wakee relationships can
858 	 * push tasks around a CPU where each wakeup moves to the next one.
859 	 * Tracking a recently used CPU allows a quick search for a recently
860 	 * used CPU that may be idle.
861 	 */
862 	int				recent_used_cpu;
863 	int				wake_cpu;
864 	int				on_rq;
865 
866 	int				prio;
867 	int				static_prio;
868 	int				normal_prio;
869 	unsigned int			rt_priority;
870 
871 	struct sched_entity		se;
872 	struct sched_rt_entity		rt;
873 	struct sched_dl_entity		dl;
874 	struct sched_dl_entity		*dl_server;
875 #ifdef CONFIG_SCHED_CLASS_EXT
876 	struct sched_ext_entity		scx;
877 #endif
878 	const struct sched_class	*sched_class;
879 
880 #ifdef CONFIG_SCHED_CORE
881 	struct rb_node			core_node;
882 	unsigned long			core_cookie;
883 	unsigned int			core_occupation;
884 #endif
885 
886 #ifdef CONFIG_CGROUP_SCHED
887 	struct task_group		*sched_task_group;
888 #ifdef CONFIG_CFS_BANDWIDTH
889 	struct callback_head		sched_throttle_work;
890 	struct list_head		throttle_node;
891 	bool				throttled;
892 #endif
893 #endif
894 
895 
896 #ifdef CONFIG_UCLAMP_TASK
897 	/*
898 	 * Clamp values requested for a scheduling entity.
899 	 * Must be updated with task_rq_lock() held.
900 	 */
901 	struct uclamp_se		uclamp_req[UCLAMP_CNT];
902 	/*
903 	 * Effective clamp values used for a scheduling entity.
904 	 * Must be updated with task_rq_lock() held.
905 	 */
906 	struct uclamp_se		uclamp[UCLAMP_CNT];
907 #endif
908 
909 	struct sched_statistics         stats;
910 
911 #ifdef CONFIG_PREEMPT_NOTIFIERS
912 	/* List of struct preempt_notifier: */
913 	struct hlist_head		preempt_notifiers;
914 #endif
915 
916 #ifdef CONFIG_BLK_DEV_IO_TRACE
917 	unsigned int			btrace_seq;
918 #endif
919 
920 	unsigned int			policy;
921 	unsigned long			max_allowed_capacity;
922 	int				nr_cpus_allowed;
923 	const cpumask_t			*cpus_ptr;
924 	cpumask_t			*user_cpus_ptr;
925 	cpumask_t			cpus_mask;
926 	void				*migration_pending;
927 	unsigned short			migration_disabled;
928 	unsigned short			migration_flags;
929 
930 #ifdef CONFIG_PREEMPT_RCU
931 	int				rcu_read_lock_nesting;
932 	union rcu_special		rcu_read_unlock_special;
933 	struct list_head		rcu_node_entry;
934 	struct rcu_node			*rcu_blocked_node;
935 #endif /* #ifdef CONFIG_PREEMPT_RCU */
936 
937 #ifdef CONFIG_TASKS_RCU
938 	unsigned long			rcu_tasks_nvcsw;
939 	u8				rcu_tasks_holdout;
940 	u8				rcu_tasks_idx;
941 	int				rcu_tasks_idle_cpu;
942 	struct list_head		rcu_tasks_holdout_list;
943 	int				rcu_tasks_exit_cpu;
944 	struct list_head		rcu_tasks_exit_list;
945 #endif /* #ifdef CONFIG_TASKS_RCU */
946 
947 #ifdef CONFIG_TASKS_TRACE_RCU
948 	int				trc_reader_nesting;
949 	struct srcu_ctr __percpu	*trc_reader_scp;
950 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */
951 
952 	struct sched_info		sched_info;
953 
954 	struct list_head		tasks;
955 	struct plist_node		pushable_tasks;
956 	struct rb_node			pushable_dl_tasks;
957 
958 	struct mm_struct		*mm;
959 	struct mm_struct		*active_mm;
960 
961 	int				exit_state;
962 	int				exit_code;
963 	int				exit_signal;
964 	/* The signal sent when the parent dies: */
965 	int				pdeath_signal;
966 	/* JOBCTL_*, siglock protected: */
967 	unsigned long			jobctl;
968 
969 	/* Used for emulating ABI behavior of previous Linux versions: */
970 	unsigned int			personality;
971 
972 	/* Scheduler bits, serialized by scheduler locks: */
973 	unsigned			sched_reset_on_fork:1;
974 	unsigned			sched_contributes_to_load:1;
975 	unsigned			sched_migrated:1;
976 	unsigned			sched_task_hot:1;
977 
978 	/* Force alignment to the next boundary: */
979 	unsigned			:0;
980 
981 	/* Unserialized, strictly 'current' */
982 
983 	/*
984 	 * This field must not be in the scheduler word above due to wakelist
985 	 * queueing no longer being serialized by p->on_cpu. However:
986 	 *
987 	 * p->XXX = X;			ttwu()
988 	 * schedule()			  if (p->on_rq && ..) // false
989 	 *   smp_mb__after_spinlock();	  if (smp_load_acquire(&p->on_cpu) && //true
990 	 *   deactivate_task()		      ttwu_queue_wakelist())
991 	 *     p->on_rq = 0;			p->sched_remote_wakeup = Y;
992 	 *
993 	 * guarantees all stores of 'current' are visible before
994 	 * ->sched_remote_wakeup gets used, so it can be in this word.
995 	 */
996 	unsigned			sched_remote_wakeup:1;
997 #ifdef CONFIG_RT_MUTEXES
998 	unsigned			sched_rt_mutex:1;
999 #endif
1000 
1001 	/* Bit to tell TOMOYO we're in execve(): */
1002 	unsigned			in_execve:1;
1003 	unsigned			in_iowait:1;
1004 #ifndef TIF_RESTORE_SIGMASK
1005 	unsigned			restore_sigmask:1;
1006 #endif
1007 #ifdef CONFIG_MEMCG_V1
1008 	unsigned			in_user_fault:1;
1009 #endif
1010 #ifdef CONFIG_LRU_GEN
1011 	/* whether the LRU algorithm may apply to this access */
1012 	unsigned			in_lru_fault:1;
1013 #endif
1014 #ifdef CONFIG_COMPAT_BRK
1015 	unsigned			brk_randomized:1;
1016 #endif
1017 #ifdef CONFIG_CGROUPS
1018 	/* disallow userland-initiated cgroup migration */
1019 	unsigned			no_cgroup_migration:1;
1020 	/* task is frozen/stopped (used by the cgroup freezer) */
1021 	unsigned			frozen:1;
1022 #endif
1023 #ifdef CONFIG_BLK_CGROUP
1024 	unsigned			use_memdelay:1;
1025 #endif
1026 #ifdef CONFIG_PSI
1027 	/* Stalled due to lack of memory */
1028 	unsigned			in_memstall:1;
1029 #endif
1030 #ifdef CONFIG_PAGE_OWNER
1031 	/* Used by page_owner=on to detect recursion in page tracking. */
1032 	unsigned			in_page_owner:1;
1033 #endif
1034 #ifdef CONFIG_EVENTFD
1035 	/* Recursion prevention for eventfd_signal() */
1036 	unsigned			in_eventfd:1;
1037 #endif
1038 #ifdef CONFIG_ARCH_HAS_CPU_PASID
1039 	unsigned			pasid_activated:1;
1040 #endif
1041 #ifdef CONFIG_X86_BUS_LOCK_DETECT
1042 	unsigned			reported_split_lock:1;
1043 #endif
1044 #ifdef CONFIG_TASK_DELAY_ACCT
1045 	/* delay due to memory thrashing */
1046 	unsigned                        in_thrashing:1;
1047 #endif
1048 	unsigned			in_nf_duplicate:1;
1049 #ifdef CONFIG_PREEMPT_RT
1050 	struct netdev_xmit		net_xmit;
1051 #endif
1052 	unsigned long			atomic_flags; /* Flags requiring atomic access. */
1053 
1054 	struct restart_block		restart_block;
1055 
1056 	pid_t				pid;
1057 	pid_t				tgid;
1058 
1059 #ifdef CONFIG_STACKPROTECTOR
1060 	/* Canary value for the -fstack-protector GCC feature: */
1061 	unsigned long			stack_canary;
1062 #endif
1063 	/*
1064 	 * Pointers to the (original) parent process, youngest child, younger sibling,
1065 	 * older sibling, respectively.  (p->father can be replaced with
1066 	 * p->real_parent->pid)
1067 	 */
1068 
1069 	/* Real parent process: */
1070 	struct task_struct __rcu	*real_parent;
1071 
1072 	/* Recipient of SIGCHLD, wait4() reports: */
1073 	struct task_struct __rcu	*parent;
1074 
1075 	/*
1076 	 * Children/sibling form the list of natural children:
1077 	 */
1078 	struct list_head		children;
1079 	struct list_head		sibling;
1080 	struct task_struct		*group_leader;
1081 
1082 	/*
1083 	 * 'ptraced' is the list of tasks this task is using ptrace() on.
1084 	 *
1085 	 * This includes both natural children and PTRACE_ATTACH targets.
1086 	 * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
1087 	 */
1088 	struct list_head		ptraced;
1089 	struct list_head		ptrace_entry;
1090 
1091 	/* PID/PID hash table linkage. */
1092 	struct pid			*thread_pid;
1093 	struct hlist_node		pid_links[PIDTYPE_MAX];
1094 	struct list_head		thread_node;
1095 
1096 	struct completion		*vfork_done;
1097 
1098 	/* CLONE_CHILD_SETTID: */
1099 	int __user			*set_child_tid;
1100 
1101 	/* CLONE_CHILD_CLEARTID: */
1102 	int __user			*clear_child_tid;
1103 
1104 	/* PF_KTHREAD | PF_IO_WORKER */
1105 	void				*worker_private;
1106 
1107 	u64				utime;
1108 	u64				stime;
1109 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
1110 	u64				utimescaled;
1111 	u64				stimescaled;
1112 #endif
1113 	u64				gtime;
1114 	struct prev_cputime		prev_cputime;
1115 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1116 	struct vtime			vtime;
1117 #endif
1118 
1119 #ifdef CONFIG_NO_HZ_FULL
1120 	atomic_t			tick_dep_mask;
1121 #endif
1122 	/* Context switch counts: */
1123 	unsigned long			nvcsw;
1124 	unsigned long			nivcsw;
1125 
1126 	/* Monotonic time in nsecs: */
1127 	u64				start_time;
1128 
1129 	/* Boot based time in nsecs: */
1130 	u64				start_boottime;
1131 
1132 	/* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
1133 	unsigned long			min_flt;
1134 	unsigned long			maj_flt;
1135 
1136 	/* Empty if CONFIG_POSIX_CPUTIMERS=n */
1137 	struct posix_cputimers		posix_cputimers;
1138 
1139 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK
1140 	struct posix_cputimers_work	posix_cputimers_work;
1141 #endif
1142 
1143 	/* Process credentials: */
1144 
1145 	/* Tracer's credentials at attach: */
1146 	const struct cred __rcu		*ptracer_cred;
1147 
1148 	/* Objective and real subjective task credentials (COW): */
1149 	const struct cred __rcu		*real_cred;
1150 
1151 	/* Effective (overridable) subjective task credentials (COW): */
1152 	const struct cred __rcu		*cred;
1153 
1154 #ifdef CONFIG_KEYS
1155 	/* Cached requested key. */
1156 	struct key			*cached_requested_key;
1157 #endif
1158 
1159 	/*
1160 	 * executable name, excluding path.
1161 	 *
1162 	 * - normally initialized begin_new_exec()
1163 	 * - set it with set_task_comm()
1164 	 *   - strscpy_pad() to ensure it is always NUL-terminated and
1165 	 *     zero-padded
1166 	 *   - task_lock() to ensure the operation is atomic and the name is
1167 	 *     fully updated.
1168 	 */
1169 	char				comm[TASK_COMM_LEN];
1170 
1171 	struct nameidata		*nameidata;
1172 
1173 #ifdef CONFIG_SYSVIPC
1174 	struct sysv_sem			sysvsem;
1175 	struct sysv_shm			sysvshm;
1176 #endif
1177 #ifdef CONFIG_DETECT_HUNG_TASK
1178 	unsigned long			last_switch_count;
1179 	unsigned long			last_switch_time;
1180 #endif
1181 	/* Filesystem information: */
1182 	struct fs_struct		*fs;
1183 
1184 	/* Open file information: */
1185 	struct files_struct		*files;
1186 
1187 #ifdef CONFIG_IO_URING
1188 	struct io_uring_task		*io_uring;
1189 	struct io_restriction		*io_uring_restrict;
1190 #endif
1191 
1192 	/* Namespaces: */
1193 	struct nsproxy			*nsproxy;
1194 
1195 	/* Signal handlers: */
1196 	struct signal_struct		*signal;
1197 	struct sighand_struct __rcu		*sighand;
1198 	sigset_t			blocked;
1199 	sigset_t			real_blocked;
1200 	/* Restored if set_restore_sigmask() was used: */
1201 	sigset_t			saved_sigmask;
1202 	struct sigpending		pending;
1203 	unsigned long			sas_ss_sp;
1204 	size_t				sas_ss_size;
1205 	unsigned int			sas_ss_flags;
1206 
1207 	struct callback_head		*task_works;
1208 
1209 #ifdef CONFIG_AUDIT
1210 #ifdef CONFIG_AUDITSYSCALL
1211 	struct audit_context		*audit_context;
1212 #endif
1213 	kuid_t				loginuid;
1214 	unsigned int			sessionid;
1215 #endif
1216 	struct seccomp			seccomp;
1217 	struct syscall_user_dispatch	syscall_dispatch;
1218 
1219 	/* Thread group tracking: */
1220 	u64				parent_exec_id;
1221 	u64				self_exec_id;
1222 
1223 	/* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
1224 	spinlock_t			alloc_lock;
1225 
1226 	/* Protection of the PI data structures: */
1227 	raw_spinlock_t			pi_lock;
1228 
1229 	struct wake_q_node		wake_q;
1230 
1231 #ifdef CONFIG_RT_MUTEXES
1232 	/* PI waiters blocked on a rt_mutex held by this task: */
1233 	struct rb_root_cached		pi_waiters;
1234 	/* Updated under owner's pi_lock and rq lock */
1235 	struct task_struct		*pi_top_task;
1236 	/* Deadlock detection and priority inheritance handling: */
1237 	struct rt_mutex_waiter		*pi_blocked_on;
1238 #endif
1239 
1240 	struct mutex			*blocked_on;	/* lock we're blocked on */
1241 
1242 #ifdef CONFIG_DETECT_HUNG_TASK_BLOCKER
1243 	/*
1244 	 * Encoded lock address causing task block (lower 2 bits = type from
1245 	 * <linux/hung_task.h>). Accessed via hung_task_*() helpers.
1246 	 */
1247 	unsigned long			blocker;
1248 #endif
1249 
1250 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1251 	int				non_block_count;
1252 #endif
1253 
1254 #ifdef CONFIG_TRACE_IRQFLAGS
1255 	struct irqtrace_events		irqtrace;
1256 	unsigned int			hardirq_threaded;
1257 	u64				hardirq_chain_key;
1258 	int				softirqs_enabled;
1259 	int				softirq_context;
1260 	int				irq_config;
1261 #endif
1262 #ifdef CONFIG_PREEMPT_RT
1263 	int				softirq_disable_cnt;
1264 #endif
1265 
1266 #ifdef CONFIG_LOCKDEP
1267 # define MAX_LOCK_DEPTH			48UL
1268 	u64				curr_chain_key;
1269 	int				lockdep_depth;
1270 	unsigned int			lockdep_recursion;
1271 	struct held_lock		held_locks[MAX_LOCK_DEPTH];
1272 #endif
1273 
1274 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP)
1275 	unsigned int			in_ubsan;
1276 #endif
1277 
1278 	/* Journalling filesystem info: */
1279 	void				*journal_info;
1280 
1281 	/* Stacked block device info: */
1282 	struct bio_list			*bio_list;
1283 
1284 	/* Stack plugging: */
1285 	struct blk_plug			*plug;
1286 
1287 	/* VM state: */
1288 	struct reclaim_state		*reclaim_state;
1289 
1290 	struct io_context		*io_context;
1291 
1292 #ifdef CONFIG_COMPACTION
1293 	struct capture_control		*capture_control;
1294 #endif
1295 	/* Ptrace state: */
1296 	unsigned long			ptrace_message;
1297 	kernel_siginfo_t		*last_siginfo;
1298 
1299 	struct task_io_accounting	ioac;
1300 #ifdef CONFIG_PSI
1301 	/* Pressure stall state */
1302 	unsigned int			psi_flags;
1303 #endif
1304 #ifdef CONFIG_TASK_XACCT
1305 	/* Accumulated RSS usage: */
1306 	u64				acct_rss_mem1;
1307 	/* Accumulated virtual memory usage: */
1308 	u64				acct_vm_mem1;
1309 	/* stime + utime since last update: */
1310 	u64				acct_timexpd;
1311 #endif
1312 #ifdef CONFIG_CPUSETS
1313 	/* Protected by ->alloc_lock: */
1314 	nodemask_t			mems_allowed;
1315 	/* Sequence number to catch updates: */
1316 	seqcount_spinlock_t		mems_allowed_seq;
1317 	int				cpuset_mem_spread_rotor;
1318 #endif
1319 #ifdef CONFIG_CGROUPS
1320 	/* Control Group info protected by css_set_lock: */
1321 	struct css_set __rcu		*cgroups;
1322 	/* cg_list protected by css_set_lock and tsk->alloc_lock: */
1323 	struct list_head		cg_list;
1324 #ifdef CONFIG_PREEMPT_RT
1325 	struct llist_node		cg_dead_lnode;
1326 #endif	/* CONFIG_PREEMPT_RT */
1327 #endif	/* CONFIG_CGROUPS */
1328 #ifdef CONFIG_X86_CPU_RESCTRL
1329 	u32				closid;
1330 	u32				rmid;
1331 #endif
1332 #ifdef CONFIG_FUTEX
1333 	struct robust_list_head __user	*robust_list;
1334 #ifdef CONFIG_COMPAT
1335 	struct compat_robust_list_head __user *compat_robust_list;
1336 #endif
1337 	struct list_head		pi_state_list;
1338 	struct futex_pi_state		*pi_state_cache;
1339 	struct mutex			futex_exit_mutex;
1340 	unsigned int			futex_state;
1341 #endif
1342 #ifdef CONFIG_PERF_EVENTS
1343 	u8				perf_recursion[PERF_NR_CONTEXTS];
1344 	struct perf_event_context	*perf_event_ctxp;
1345 	struct mutex			perf_event_mutex;
1346 	struct list_head		perf_event_list;
1347 	struct perf_ctx_data __rcu	*perf_ctx_data;
1348 #endif
1349 #ifdef CONFIG_DEBUG_PREEMPT
1350 	unsigned long			preempt_disable_ip;
1351 #endif
1352 #ifdef CONFIG_NUMA
1353 	/* Protected by alloc_lock: */
1354 	struct mempolicy		*mempolicy;
1355 	short				il_prev;
1356 	u8				il_weight;
1357 	short				pref_node_fork;
1358 #endif
1359 #ifdef CONFIG_NUMA_BALANCING
1360 	int				numa_scan_seq;
1361 	unsigned int			numa_scan_period;
1362 	unsigned int			numa_scan_period_max;
1363 	int				numa_preferred_nid;
1364 	unsigned long			numa_migrate_retry;
1365 	/* Migration stamp: */
1366 	u64				node_stamp;
1367 	u64				last_task_numa_placement;
1368 	u64				last_sum_exec_runtime;
1369 	struct callback_head		numa_work;
1370 
1371 	/*
1372 	 * This pointer is only modified for current in syscall and
1373 	 * pagefault context (and for tasks being destroyed), so it can be read
1374 	 * from any of the following contexts:
1375 	 *  - RCU read-side critical section
1376 	 *  - current->numa_group from everywhere
1377 	 *  - task's runqueue locked, task not running
1378 	 */
1379 	struct numa_group __rcu		*numa_group;
1380 
1381 	/*
1382 	 * numa_faults is an array split into four regions:
1383 	 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1384 	 * in this precise order.
1385 	 *
1386 	 * faults_memory: Exponential decaying average of faults on a per-node
1387 	 * basis. Scheduling placement decisions are made based on these
1388 	 * counts. The values remain static for the duration of a PTE scan.
1389 	 * faults_cpu: Track the nodes the process was running on when a NUMA
1390 	 * hinting fault was incurred.
1391 	 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1392 	 * during the current scan window. When the scan completes, the counts
1393 	 * in faults_memory and faults_cpu decay and these values are copied.
1394 	 */
1395 	unsigned long			*numa_faults;
1396 	unsigned long			total_numa_faults;
1397 
1398 	/*
1399 	 * numa_faults_locality tracks if faults recorded during the last
1400 	 * scan window were remote/local or failed to migrate. The task scan
1401 	 * period is adapted based on the locality of the faults with different
1402 	 * weights depending on whether they were shared or private faults
1403 	 */
1404 	unsigned long			numa_faults_locality[3];
1405 
1406 	unsigned long			numa_pages_migrated;
1407 #endif /* CONFIG_NUMA_BALANCING */
1408 
1409 	struct rseq_data		rseq;
1410 	struct sched_mm_cid		mm_cid;
1411 
1412 	struct tlbflush_unmap_batch	tlb_ubc;
1413 
1414 	/* Cache last used pipe for splice(): */
1415 	struct pipe_inode_info		*splice_pipe;
1416 
1417 	struct page_frag		task_frag;
1418 
1419 #ifdef CONFIG_ARCH_HAS_LAZY_MMU_MODE
1420 	struct lazy_mmu_state		lazy_mmu_state;
1421 #endif
1422 
1423 #ifdef CONFIG_TASK_DELAY_ACCT
1424 	struct task_delay_info		*delays;
1425 #endif
1426 
1427 #ifdef CONFIG_FAULT_INJECTION
1428 	int				make_it_fail;
1429 	unsigned int			fail_nth;
1430 #endif
1431 	/*
1432 	 * When (nr_dirtied >= nr_dirtied_pause), it's time to call
1433 	 * balance_dirty_pages() for a dirty throttling pause:
1434 	 */
1435 	int				nr_dirtied;
1436 	int				nr_dirtied_pause;
1437 	/* Start of a write-and-pause period: */
1438 	unsigned long			dirty_paused_when;
1439 
1440 #ifdef CONFIG_LATENCYTOP
1441 	int				latency_record_count;
1442 	struct latency_record		latency_record[LT_SAVECOUNT];
1443 #endif
1444 	/*
1445 	 * Time slack values; these are used to round up poll() and
1446 	 * select() etc timeout values. These are in nanoseconds.
1447 	 */
1448 	u64				timer_slack_ns;
1449 	u64				default_timer_slack_ns;
1450 
1451 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
1452 	unsigned int			kasan_depth;
1453 #endif
1454 
1455 #ifdef CONFIG_KCSAN
1456 	struct kcsan_ctx		kcsan_ctx;
1457 #ifdef CONFIG_TRACE_IRQFLAGS
1458 	struct irqtrace_events		kcsan_save_irqtrace;
1459 #endif
1460 #ifdef CONFIG_KCSAN_WEAK_MEMORY
1461 	int				kcsan_stack_depth;
1462 #endif
1463 #endif
1464 
1465 #ifdef CONFIG_KMSAN
1466 	struct kmsan_ctx		kmsan_ctx;
1467 #endif
1468 
1469 #if IS_ENABLED(CONFIG_KUNIT)
1470 	struct kunit			*kunit_test;
1471 #endif
1472 
1473 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1474 	/* Index of current stored address in ret_stack: */
1475 	int				curr_ret_stack;
1476 	int				curr_ret_depth;
1477 
1478 	/* Stack of return addresses for return function tracing: */
1479 	unsigned long			*ret_stack;
1480 
1481 	/* Timestamp for last schedule: */
1482 	unsigned long long		ftrace_timestamp;
1483 	unsigned long long		ftrace_sleeptime;
1484 
1485 	/*
1486 	 * Number of functions that haven't been traced
1487 	 * because of depth overrun:
1488 	 */
1489 	atomic_t			trace_overrun;
1490 
1491 	/* Pause tracing: */
1492 	atomic_t			tracing_graph_pause;
1493 #endif
1494 
1495 #ifdef CONFIG_TRACING
1496 	/* Bitmask and counter of trace recursion: */
1497 	unsigned long			trace_recursion;
1498 #endif /* CONFIG_TRACING */
1499 
1500 #ifdef CONFIG_KCOV
1501 	/* See kernel/kcov.c for more details. */
1502 
1503 	/* Coverage collection mode enabled for this task (0 if disabled): */
1504 	unsigned int			kcov_mode;
1505 
1506 	/* Size of the kcov_area: */
1507 	unsigned int			kcov_size;
1508 
1509 	/* Buffer for coverage collection: */
1510 	void				*kcov_area;
1511 
1512 	/* KCOV descriptor wired with this task or NULL: */
1513 	struct kcov			*kcov;
1514 
1515 	/* KCOV common handle for remote coverage collection: */
1516 	u64				kcov_handle;
1517 
1518 	/* KCOV sequence number: */
1519 	int				kcov_sequence;
1520 
1521 	/* Collect coverage from softirq context: */
1522 	unsigned int			kcov_softirq;
1523 #endif
1524 
1525 #ifdef CONFIG_MEMCG_V1
1526 	struct mem_cgroup		*memcg_in_oom;
1527 #endif
1528 
1529 #ifdef CONFIG_MEMCG
1530 	/* Number of pages to reclaim on returning to userland: */
1531 	unsigned int			memcg_nr_pages_over_high;
1532 
1533 	/* Used by memcontrol for targeted memcg charge: */
1534 	struct mem_cgroup		*active_memcg;
1535 
1536 	/* Cache for current->cgroups->memcg->objcg lookups: */
1537 	struct obj_cgroup		*objcg;
1538 #endif
1539 
1540 #ifdef CONFIG_BLK_CGROUP
1541 	struct gendisk			*throttle_disk;
1542 #endif
1543 
1544 #ifdef CONFIG_UPROBES
1545 	struct uprobe_task		*utask;
1546 #endif
1547 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1548 	unsigned int			sequential_io;
1549 	unsigned int			sequential_io_avg;
1550 #endif
1551 	struct kmap_ctrl		kmap_ctrl;
1552 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1553 	unsigned long			task_state_change;
1554 # ifdef CONFIG_PREEMPT_RT
1555 	unsigned long			saved_state_change;
1556 # endif
1557 #endif
1558 	struct rcu_head			rcu;
1559 	refcount_t			rcu_users;
1560 	int				pagefault_disabled;
1561 #ifdef CONFIG_MMU
1562 	struct task_struct		*oom_reaper_list;
1563 	struct timer_list		oom_reaper_timer;
1564 #endif
1565 #ifdef CONFIG_VMAP_STACK
1566 	struct vm_struct		*stack_vm_area;
1567 #endif
1568 #ifdef CONFIG_THREAD_INFO_IN_TASK
1569 	/* A live task holds one reference: */
1570 	refcount_t			stack_refcount;
1571 #endif
1572 #ifdef CONFIG_LIVEPATCH
1573 	int patch_state;
1574 #endif
1575 #ifdef CONFIG_SECURITY
1576 	/* Used by LSM modules for access restriction: */
1577 	void				*security;
1578 #endif
1579 #ifdef CONFIG_BPF_SYSCALL
1580 	/* Used by BPF task local storage */
1581 	struct bpf_local_storage __rcu	*bpf_storage;
1582 	/* Used for BPF run context */
1583 	struct bpf_run_ctx		*bpf_ctx;
1584 #endif
1585 	/* Used by BPF for per-TASK xdp storage */
1586 	struct bpf_net_context		*bpf_net_context;
1587 
1588 #ifdef CONFIG_KSTACK_ERASE
1589 	unsigned long			lowest_stack;
1590 #endif
1591 #ifdef CONFIG_KSTACK_ERASE_METRICS
1592 	unsigned long			prev_lowest_stack;
1593 #endif
1594 
1595 #ifdef CONFIG_X86_MCE
1596 	void __user			*mce_vaddr;
1597 	__u64				mce_kflags;
1598 	u64				mce_addr;
1599 	__u64				mce_ripv : 1,
1600 					mce_whole_page : 1,
1601 					__mce_reserved : 62;
1602 	struct callback_head		mce_kill_me;
1603 	int				mce_count;
1604 #endif
1605 
1606 #ifdef CONFIG_KRETPROBES
1607 	struct llist_head               kretprobe_instances;
1608 #endif
1609 #ifdef CONFIG_RETHOOK
1610 	struct llist_head               rethooks;
1611 #endif
1612 
1613 #ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH
1614 	/*
1615 	 * If L1D flush is supported on mm context switch
1616 	 * then we use this callback head to queue kill work
1617 	 * to kill tasks that are not running on SMT disabled
1618 	 * cores
1619 	 */
1620 	struct callback_head		l1d_flush_kill;
1621 #endif
1622 
1623 #ifdef CONFIG_RV
1624 	/*
1625 	 * Per-task RV monitor, fixed in CONFIG_RV_PER_TASK_MONITORS.
1626 	 * If memory becomes a concern, we can think about a dynamic method.
1627 	 */
1628 	union rv_task_monitor		rv[CONFIG_RV_PER_TASK_MONITORS];
1629 #endif
1630 
1631 #ifdef CONFIG_USER_EVENTS
1632 	struct user_event_mm		*user_event_mm;
1633 #endif
1634 
1635 #ifdef CONFIG_UNWIND_USER
1636 	struct unwind_task_info		unwind_info;
1637 #endif
1638 
1639 	/* CPU-specific state of this task: */
1640 	struct thread_struct		thread;
1641 
1642 	/*
1643 	 * New fields for task_struct should be added above here, so that
1644 	 * they are included in the randomized portion of task_struct.
1645 	 */
1646 	randomized_struct_fields_end
1647 } __attribute__ ((aligned (64)));
1648 
1649 #ifdef CONFIG_SCHED_PROXY_EXEC
1650 DECLARE_STATIC_KEY_TRUE(__sched_proxy_exec);
sched_proxy_exec(void)1651 static inline bool sched_proxy_exec(void)
1652 {
1653 	return static_branch_likely(&__sched_proxy_exec);
1654 }
1655 #else
sched_proxy_exec(void)1656 static inline bool sched_proxy_exec(void)
1657 {
1658 	return false;
1659 }
1660 #endif
1661 
1662 #define TASK_REPORT_IDLE	(TASK_REPORT + 1)
1663 #define TASK_REPORT_MAX		(TASK_REPORT_IDLE << 1)
1664 
__task_state_index(unsigned int tsk_state,unsigned int tsk_exit_state)1665 static inline unsigned int __task_state_index(unsigned int tsk_state,
1666 					      unsigned int tsk_exit_state)
1667 {
1668 	unsigned int state = (tsk_state | tsk_exit_state) & TASK_REPORT;
1669 
1670 	BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);
1671 
1672 	if ((tsk_state & TASK_IDLE) == TASK_IDLE)
1673 		state = TASK_REPORT_IDLE;
1674 
1675 	/*
1676 	 * We're lying here, but rather than expose a completely new task state
1677 	 * to userspace, we can make this appear as if the task has gone through
1678 	 * a regular rt_mutex_lock() call.
1679 	 * Report frozen tasks as uninterruptible.
1680 	 */
1681 	if ((tsk_state & TASK_RTLOCK_WAIT) || (tsk_state & TASK_FROZEN))
1682 		state = TASK_UNINTERRUPTIBLE;
1683 
1684 	return fls(state);
1685 }
1686 
task_state_index(struct task_struct * tsk)1687 static inline unsigned int task_state_index(struct task_struct *tsk)
1688 {
1689 	return __task_state_index(READ_ONCE(tsk->__state), tsk->exit_state);
1690 }
1691 
task_index_to_char(unsigned int state)1692 static inline char task_index_to_char(unsigned int state)
1693 {
1694 	static const char state_char[] = "RSDTtXZPI";
1695 
1696 	BUILD_BUG_ON(TASK_REPORT_MAX * 2 != 1 << (sizeof(state_char) - 1));
1697 
1698 	return state_char[state];
1699 }
1700 
task_state_to_char(struct task_struct * tsk)1701 static inline char task_state_to_char(struct task_struct *tsk)
1702 {
1703 	return task_index_to_char(task_state_index(tsk));
1704 }
1705 
1706 #ifdef CONFIG_ARCH_HAS_LAZY_MMU_MODE
1707 /**
1708  * __task_lazy_mmu_mode_active() - Test the lazy MMU mode state for a task.
1709  * @tsk: The task to check.
1710  *
1711  * Test whether @tsk has its lazy MMU mode state set to active (i.e. enabled
1712  * and not paused).
1713  *
1714  * This function only considers the state saved in task_struct; to test whether
1715  * current actually is in lazy MMU mode, is_lazy_mmu_mode_active() should be
1716  * used instead.
1717  *
1718  * This function is intended for architectures that implement the lazy MMU
1719  * mode; it must not be called from generic code.
1720  */
__task_lazy_mmu_mode_active(struct task_struct * tsk)1721 static inline bool __task_lazy_mmu_mode_active(struct task_struct *tsk)
1722 {
1723 	struct lazy_mmu_state *state = &tsk->lazy_mmu_state;
1724 
1725 	return state->enable_count > 0 && state->pause_count == 0;
1726 }
1727 
1728 /**
1729  * is_lazy_mmu_mode_active() - Test whether we are currently in lazy MMU mode.
1730  *
1731  * Test whether the current context is in lazy MMU mode. This is true if both:
1732  * 1. We are not in interrupt context
1733  * 2. Lazy MMU mode is active for the current task
1734  *
1735  * This function is intended for architectures that implement the lazy MMU
1736  * mode; it must not be called from generic code.
1737  */
is_lazy_mmu_mode_active(void)1738 static inline bool is_lazy_mmu_mode_active(void)
1739 {
1740 	if (in_interrupt())
1741 		return false;
1742 
1743 	return __task_lazy_mmu_mode_active(current);
1744 }
1745 #endif
1746 
1747 extern struct pid *cad_pid;
1748 
1749 /*
1750  * Per process flags
1751  */
1752 #define PF_VCPU			0x00000001	/* I'm a virtual CPU */
1753 #define PF_IDLE			0x00000002	/* I am an IDLE thread */
1754 #define PF_EXITING		0x00000004	/* Getting shut down */
1755 #define PF_POSTCOREDUMP		0x00000008	/* Coredumps should ignore this task */
1756 #define PF_IO_WORKER		0x00000010	/* Task is an IO worker */
1757 #define PF_WQ_WORKER		0x00000020	/* I'm a workqueue worker */
1758 #define PF_FORKNOEXEC		0x00000040	/* Forked but didn't exec */
1759 #define PF_MCE_PROCESS		0x00000080      /* Process policy on mce errors */
1760 #define PF_SUPERPRIV		0x00000100	/* Used super-user privileges */
1761 #define PF_DUMPCORE		0x00000200	/* Dumped core */
1762 #define PF_SIGNALED		0x00000400	/* Killed by a signal */
1763 #define PF_MEMALLOC		0x00000800	/* Allocating memory to free memory. See memalloc_noreclaim_save() */
1764 #define PF_NPROC_EXCEEDED	0x00001000	/* set_user() noticed that RLIMIT_NPROC was exceeded */
1765 #define PF_USED_MATH		0x00002000	/* If unset the fpu must be initialized before use */
1766 #define PF_USER_WORKER		0x00004000	/* Kernel thread cloned from userspace thread */
1767 #define PF_NOFREEZE		0x00008000	/* This thread should not be frozen */
1768 #define PF_KCOMPACTD		0x00010000	/* I am kcompactd */
1769 #define PF_KSWAPD		0x00020000	/* I am kswapd */
1770 #define PF_MEMALLOC_NOFS	0x00040000	/* All allocations inherit GFP_NOFS. See memalloc_nfs_save() */
1771 #define PF_MEMALLOC_NOIO	0x00080000	/* All allocations inherit GFP_NOIO. See memalloc_noio_save() */
1772 #define PF_LOCAL_THROTTLE	0x00100000	/* Throttle writes only against the bdi I write to,
1773 						 * I am cleaning dirty pages from some other bdi. */
1774 #define PF_KTHREAD		0x00200000	/* I am a kernel thread */
1775 #define PF_RANDOMIZE		0x00400000	/* Randomize virtual address space */
1776 #define PF__HOLE__00800000	0x00800000
1777 #define PF__HOLE__01000000	0x01000000
1778 #define PF__HOLE__02000000	0x02000000
1779 #define PF_NO_SETAFFINITY	0x04000000	/* Userland is not allowed to meddle with cpus_mask */
1780 #define PF_MCE_EARLY		0x08000000      /* Early kill for mce process policy */
1781 #define PF_MEMALLOC_PIN		0x10000000	/* Allocations constrained to zones which allow long term pinning.
1782 						 * See memalloc_pin_save() */
1783 #define PF_BLOCK_TS		0x20000000	/* plug has ts that needs updating */
1784 #define PF__HOLE__40000000	0x40000000
1785 #define PF_SUSPEND_TASK		0x80000000      /* This thread called freeze_processes() and should not be frozen */
1786 
1787 /*
1788  * Only the _current_ task can read/write to tsk->flags, but other
1789  * tasks can access tsk->flags in readonly mode for example
1790  * with tsk_used_math (like during threaded core dumping).
1791  * There is however an exception to this rule during ptrace
1792  * or during fork: the ptracer task is allowed to write to the
1793  * child->flags of its traced child (same goes for fork, the parent
1794  * can write to the child->flags), because we're guaranteed the
1795  * child is not running and in turn not changing child->flags
1796  * at the same time the parent does it.
1797  */
1798 #define clear_stopped_child_used_math(child)	do { (child)->flags &= ~PF_USED_MATH; } while (0)
1799 #define set_stopped_child_used_math(child)	do { (child)->flags |= PF_USED_MATH; } while (0)
1800 #define clear_used_math()			clear_stopped_child_used_math(current)
1801 #define set_used_math()				set_stopped_child_used_math(current)
1802 
1803 #define conditional_stopped_child_used_math(condition, child) \
1804 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1805 
1806 #define conditional_used_math(condition)	conditional_stopped_child_used_math(condition, current)
1807 
1808 #define copy_to_stopped_child_used_math(child) \
1809 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1810 
1811 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1812 #define tsk_used_math(p)			((p)->flags & PF_USED_MATH)
1813 #define used_math()				tsk_used_math(current)
1814 
is_percpu_thread(void)1815 static __always_inline bool is_percpu_thread(void)
1816 {
1817 	return (current->flags & PF_NO_SETAFFINITY) &&
1818 		(current->nr_cpus_allowed  == 1);
1819 }
1820 
is_user_task(struct task_struct * task)1821 static __always_inline bool is_user_task(struct task_struct *task)
1822 {
1823 	return task->mm && !(task->flags & (PF_KTHREAD | PF_USER_WORKER));
1824 }
1825 
1826 /* Per-process atomic flags. */
1827 #define PFA_NO_NEW_PRIVS		0	/* May not gain new privileges. */
1828 #define PFA_SPREAD_PAGE			1	/* Spread page cache over cpuset */
1829 #define PFA_SPREAD_SLAB			2	/* Spread some slab caches over cpuset */
1830 #define PFA_SPEC_SSB_DISABLE		3	/* Speculative Store Bypass disabled */
1831 #define PFA_SPEC_SSB_FORCE_DISABLE	4	/* Speculative Store Bypass force disabled*/
1832 #define PFA_SPEC_IB_DISABLE		5	/* Indirect branch speculation restricted */
1833 #define PFA_SPEC_IB_FORCE_DISABLE	6	/* Indirect branch speculation permanently restricted */
1834 #define PFA_SPEC_SSB_NOEXEC		7	/* Speculative Store Bypass clear on execve() */
1835 
1836 #define TASK_PFA_TEST(name, func)					\
1837 	static inline bool task_##func(struct task_struct *p)		\
1838 	{ return test_bit(PFA_##name, &p->atomic_flags); }
1839 
1840 #define TASK_PFA_SET(name, func)					\
1841 	static inline void task_set_##func(struct task_struct *p)	\
1842 	{ set_bit(PFA_##name, &p->atomic_flags); }
1843 
1844 #define TASK_PFA_CLEAR(name, func)					\
1845 	static inline void task_clear_##func(struct task_struct *p)	\
1846 	{ clear_bit(PFA_##name, &p->atomic_flags); }
1847 
TASK_PFA_TEST(NO_NEW_PRIVS,no_new_privs)1848 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1849 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1850 
1851 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1852 TASK_PFA_SET(SPREAD_PAGE, spread_page)
1853 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
1854 
1855 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
1856 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
1857 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1858 
1859 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable)
1860 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable)
1861 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable)
1862 
1863 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1864 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1865 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1866 
1867 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1868 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1869 
1870 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable)
1871 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable)
1872 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable)
1873 
1874 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1875 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1876 
1877 static inline void
1878 current_restore_flags(unsigned long orig_flags, unsigned long flags)
1879 {
1880 	current->flags &= ~flags;
1881 	current->flags |= orig_flags & flags;
1882 }
1883 
1884 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
1885 extern int task_can_attach(struct task_struct *p);
1886 extern int dl_bw_alloc(int cpu, u64 dl_bw);
1887 extern void dl_bw_free(int cpu, u64 dl_bw);
1888 
1889 /* set_cpus_allowed_force() - consider using set_cpus_allowed_ptr() instead */
1890 extern void set_cpus_allowed_force(struct task_struct *p, const struct cpumask *new_mask);
1891 
1892 /**
1893  * set_cpus_allowed_ptr - set CPU affinity mask of a task
1894  * @p: the task
1895  * @new_mask: CPU affinity mask
1896  *
1897  * Return: zero if successful, or a negative error code
1898  */
1899 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
1900 extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node);
1901 extern void release_user_cpus_ptr(struct task_struct *p);
1902 extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask);
1903 extern void force_compatible_cpus_allowed_ptr(struct task_struct *p);
1904 extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p);
1905 
1906 extern int yield_to(struct task_struct *p, bool preempt);
1907 extern void set_user_nice(struct task_struct *p, long nice);
1908 extern int task_prio(const struct task_struct *p);
1909 
1910 /**
1911  * task_nice - return the nice value of a given task.
1912  * @p: the task in question.
1913  *
1914  * Return: The nice value [ -20 ... 0 ... 19 ].
1915  */
task_nice(const struct task_struct * p)1916 static inline int task_nice(const struct task_struct *p)
1917 {
1918 	return PRIO_TO_NICE((p)->static_prio);
1919 }
1920 
1921 extern int can_nice(const struct task_struct *p, const int nice);
1922 extern int task_curr(const struct task_struct *p);
1923 extern int idle_cpu(int cpu);
1924 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
1925 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
1926 extern void sched_set_fifo(struct task_struct *p);
1927 extern void sched_set_fifo_low(struct task_struct *p);
1928 extern void sched_set_fifo_secondary(struct task_struct *p);
1929 extern void sched_set_normal(struct task_struct *p, int nice);
1930 extern int sched_setattr(struct task_struct *, const struct sched_attr *);
1931 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *);
1932 extern struct task_struct *idle_task(int cpu);
1933 
1934 /**
1935  * is_idle_task - is the specified task an idle task?
1936  * @p: the task in question.
1937  *
1938  * Return: 1 if @p is an idle task. 0 otherwise.
1939  */
is_idle_task(const struct task_struct * p)1940 static __always_inline bool is_idle_task(const struct task_struct *p)
1941 {
1942 	return !!(p->flags & PF_IDLE);
1943 }
1944 
1945 extern struct task_struct *curr_task(int cpu);
1946 extern void ia64_set_curr_task(int cpu, struct task_struct *p);
1947 
1948 void yield(void);
1949 
1950 union thread_union {
1951 	struct task_struct task;
1952 #ifndef CONFIG_THREAD_INFO_IN_TASK
1953 	struct thread_info thread_info;
1954 #endif
1955 	unsigned long stack[THREAD_SIZE/sizeof(long)];
1956 };
1957 
1958 #ifndef CONFIG_THREAD_INFO_IN_TASK
1959 extern struct thread_info init_thread_info;
1960 #endif
1961 
1962 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];
1963 
1964 #ifdef CONFIG_THREAD_INFO_IN_TASK
1965 # define task_thread_info(task)	(&(task)->thread_info)
1966 #else
1967 # define task_thread_info(task)	((struct thread_info *)(task)->stack)
1968 #endif
1969 
1970 /*
1971  * find a task by one of its numerical ids
1972  *
1973  * find_task_by_pid_ns():
1974  *      finds a task by its pid in the specified namespace
1975  * find_task_by_vpid():
1976  *      finds a task by its virtual pid
1977  *
1978  * see also find_vpid() etc in include/linux/pid.h
1979  */
1980 
1981 extern struct task_struct *find_task_by_vpid(pid_t nr);
1982 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns);
1983 
1984 /*
1985  * find a task by its virtual pid and get the task struct
1986  */
1987 extern struct task_struct *find_get_task_by_vpid(pid_t nr);
1988 
1989 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1990 extern int wake_up_process(struct task_struct *tsk);
1991 extern void wake_up_new_task(struct task_struct *tsk);
1992 
1993 extern void kick_process(struct task_struct *tsk);
1994 
1995 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
1996 #define set_task_comm(tsk, from) ({			\
1997 	BUILD_BUG_ON(sizeof(from) != TASK_COMM_LEN);	\
1998 	__set_task_comm(tsk, from, false);		\
1999 })
2000 
2001 /*
2002  * - Why not use task_lock()?
2003  *   User space can randomly change their names anyway, so locking for readers
2004  *   doesn't make sense. For writers, locking is probably necessary, as a race
2005  *   condition could lead to long-term mixed results.
2006  *   The strscpy_pad() in __set_task_comm() can ensure that the task comm is
2007  *   always NUL-terminated and zero-padded. Therefore the race condition between
2008  *   reader and writer is not an issue.
2009  *
2010  * - BUILD_BUG_ON() can help prevent the buf from being truncated.
2011  *   Since the callers don't perform any return value checks, this safeguard is
2012  *   necessary.
2013  */
2014 #define get_task_comm(buf, tsk) ({			\
2015 	BUILD_BUG_ON(sizeof(buf) < TASK_COMM_LEN);	\
2016 	strscpy_pad(buf, (tsk)->comm);			\
2017 	buf;						\
2018 })
2019 
scheduler_ipi(void)2020 static __always_inline void scheduler_ipi(void)
2021 {
2022 	/*
2023 	 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting
2024 	 * TIF_NEED_RESCHED remotely (for the first time) will also send
2025 	 * this IPI.
2026 	 */
2027 	preempt_fold_need_resched();
2028 }
2029 
2030 extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state);
2031 
2032 /*
2033  * Set thread flags in other task's structures.
2034  * See asm/thread_info.h for TIF_xxxx flags available:
2035  */
set_tsk_thread_flag(struct task_struct * tsk,int flag)2036 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2037 {
2038 	set_ti_thread_flag(task_thread_info(tsk), flag);
2039 }
2040 
clear_tsk_thread_flag(struct task_struct * tsk,int flag)2041 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2042 {
2043 	clear_ti_thread_flag(task_thread_info(tsk), flag);
2044 }
2045 
update_tsk_thread_flag(struct task_struct * tsk,int flag,bool value)2046 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag,
2047 					  bool value)
2048 {
2049 	update_ti_thread_flag(task_thread_info(tsk), flag, value);
2050 }
2051 
test_and_set_tsk_thread_flag(struct task_struct * tsk,int flag)2052 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2053 {
2054 	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2055 }
2056 
test_and_clear_tsk_thread_flag(struct task_struct * tsk,int flag)2057 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2058 {
2059 	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2060 }
2061 
test_tsk_thread_flag(struct task_struct * tsk,int flag)2062 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2063 {
2064 	return test_ti_thread_flag(task_thread_info(tsk), flag);
2065 }
2066 
set_tsk_need_resched(struct task_struct * tsk)2067 static inline void set_tsk_need_resched(struct task_struct *tsk)
2068 {
2069 	if (tracepoint_enabled(sched_set_need_resched_tp) &&
2070 	    !test_tsk_thread_flag(tsk, TIF_NEED_RESCHED))
2071 		__trace_set_need_resched(tsk, TIF_NEED_RESCHED);
2072 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2073 }
2074 
clear_tsk_need_resched(struct task_struct * tsk)2075 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2076 {
2077 	atomic_long_andnot(_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY,
2078 			   (atomic_long_t *)&task_thread_info(tsk)->flags);
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 
set_need_resched_current(void)2086 static inline void set_need_resched_current(void)
2087 {
2088 	lockdep_assert_irqs_disabled();
2089 	set_tsk_need_resched(current);
2090 	set_preempt_need_resched();
2091 }
2092 
2093 /*
2094  * cond_resched() and cond_resched_lock(): latency reduction via
2095  * explicit rescheduling in places that are safe. The return
2096  * value indicates whether a reschedule was done in fact.
2097  * cond_resched_lock() will drop the spinlock before scheduling,
2098  */
2099 #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC)
2100 extern int __cond_resched(void);
2101 
2102 #if defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL)
2103 
2104 DECLARE_STATIC_CALL(cond_resched, __cond_resched);
2105 
_cond_resched(void)2106 static __always_inline int _cond_resched(void)
2107 {
2108 	return static_call_mod(cond_resched)();
2109 }
2110 
2111 #elif defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY)
2112 
2113 extern int dynamic_cond_resched(void);
2114 
_cond_resched(void)2115 static __always_inline int _cond_resched(void)
2116 {
2117 	return dynamic_cond_resched();
2118 }
2119 
2120 #else /* !CONFIG_PREEMPTION */
2121 
_cond_resched(void)2122 static inline int _cond_resched(void)
2123 {
2124 	return __cond_resched();
2125 }
2126 
2127 #endif /* PREEMPT_DYNAMIC && CONFIG_HAVE_PREEMPT_DYNAMIC_CALL */
2128 
2129 #else /* CONFIG_PREEMPTION && !CONFIG_PREEMPT_DYNAMIC */
2130 
_cond_resched(void)2131 static inline int _cond_resched(void)
2132 {
2133 	return 0;
2134 }
2135 
2136 #endif /* !CONFIG_PREEMPTION || CONFIG_PREEMPT_DYNAMIC */
2137 
2138 #define cond_resched() ({			\
2139 	__might_resched(__FILE__, __LINE__, 0);	\
2140 	_cond_resched();			\
2141 })
2142 
2143 extern int __cond_resched_lock(spinlock_t *lock) __must_hold(lock);
2144 extern int __cond_resched_rwlock_read(rwlock_t *lock) __must_hold_shared(lock);
2145 extern int __cond_resched_rwlock_write(rwlock_t *lock) __must_hold(lock);
2146 
2147 #define MIGHT_RESCHED_RCU_SHIFT		8
2148 #define MIGHT_RESCHED_PREEMPT_MASK	((1U << MIGHT_RESCHED_RCU_SHIFT) - 1)
2149 
2150 #ifndef CONFIG_PREEMPT_RT
2151 /*
2152  * Non RT kernels have an elevated preempt count due to the held lock,
2153  * but are not allowed to be inside a RCU read side critical section
2154  */
2155 # define PREEMPT_LOCK_RESCHED_OFFSETS	PREEMPT_LOCK_OFFSET
2156 #else
2157 /*
2158  * spin/rw_lock() on RT implies rcu_read_lock(). The might_sleep() check in
2159  * cond_resched*lock() has to take that into account because it checks for
2160  * preempt_count() and rcu_preempt_depth().
2161  */
2162 # define PREEMPT_LOCK_RESCHED_OFFSETS	\
2163 	(PREEMPT_LOCK_OFFSET + (1U << MIGHT_RESCHED_RCU_SHIFT))
2164 #endif
2165 
2166 #define cond_resched_lock(lock) ({						\
2167 	__might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS);	\
2168 	__cond_resched_lock(lock);						\
2169 })
2170 
2171 #define cond_resched_rwlock_read(lock) ({					\
2172 	__might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS);	\
2173 	__cond_resched_rwlock_read(lock);					\
2174 })
2175 
2176 #define cond_resched_rwlock_write(lock) ({					\
2177 	__might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS);	\
2178 	__cond_resched_rwlock_write(lock);					\
2179 })
2180 
2181 #ifndef CONFIG_PREEMPT_RT
__get_task_blocked_on(struct task_struct * p)2182 static inline struct mutex *__get_task_blocked_on(struct task_struct *p)
2183 {
2184 	struct mutex *m = p->blocked_on;
2185 
2186 	if (m)
2187 		lockdep_assert_held_once(&m->wait_lock);
2188 	return m;
2189 }
2190 
__set_task_blocked_on(struct task_struct * p,struct mutex * m)2191 static inline void __set_task_blocked_on(struct task_struct *p, struct mutex *m)
2192 {
2193 	struct mutex *blocked_on = READ_ONCE(p->blocked_on);
2194 
2195 	WARN_ON_ONCE(!m);
2196 	/* The task should only be setting itself as blocked */
2197 	WARN_ON_ONCE(p != current);
2198 	/* Currently we serialize blocked_on under the mutex::wait_lock */
2199 	lockdep_assert_held_once(&m->wait_lock);
2200 	/*
2201 	 * Check ensure we don't overwrite existing mutex value
2202 	 * with a different mutex. Note, setting it to the same
2203 	 * lock repeatedly is ok.
2204 	 */
2205 	WARN_ON_ONCE(blocked_on && blocked_on != m);
2206 	WRITE_ONCE(p->blocked_on, m);
2207 }
2208 
set_task_blocked_on(struct task_struct * p,struct mutex * m)2209 static inline void set_task_blocked_on(struct task_struct *p, struct mutex *m)
2210 {
2211 	guard(raw_spinlock_irqsave)(&m->wait_lock);
2212 	__set_task_blocked_on(p, m);
2213 }
2214 
__clear_task_blocked_on(struct task_struct * p,struct mutex * m)2215 static inline void __clear_task_blocked_on(struct task_struct *p, struct mutex *m)
2216 {
2217 	if (m) {
2218 		struct mutex *blocked_on = READ_ONCE(p->blocked_on);
2219 
2220 		/* Currently we serialize blocked_on under the mutex::wait_lock */
2221 		lockdep_assert_held_once(&m->wait_lock);
2222 		/*
2223 		 * There may be cases where we re-clear already cleared
2224 		 * blocked_on relationships, but make sure we are not
2225 		 * clearing the relationship with a different lock.
2226 		 */
2227 		WARN_ON_ONCE(blocked_on && blocked_on != m);
2228 	}
2229 	WRITE_ONCE(p->blocked_on, NULL);
2230 }
2231 
clear_task_blocked_on(struct task_struct * p,struct mutex * m)2232 static inline void clear_task_blocked_on(struct task_struct *p, struct mutex *m)
2233 {
2234 	guard(raw_spinlock_irqsave)(&m->wait_lock);
2235 	__clear_task_blocked_on(p, m);
2236 }
2237 #else
__clear_task_blocked_on(struct task_struct * p,struct rt_mutex * m)2238 static inline void __clear_task_blocked_on(struct task_struct *p, struct rt_mutex *m)
2239 {
2240 }
2241 
clear_task_blocked_on(struct task_struct * p,struct rt_mutex * m)2242 static inline void clear_task_blocked_on(struct task_struct *p, struct rt_mutex *m)
2243 {
2244 }
2245 #endif /* !CONFIG_PREEMPT_RT */
2246 
need_resched(void)2247 static __always_inline bool need_resched(void)
2248 {
2249 	return unlikely(tif_need_resched());
2250 }
2251 
2252 /*
2253  * Wrappers for p->thread_info->cpu access. No-op on UP.
2254  */
2255 #ifdef CONFIG_SMP
2256 
task_cpu(const struct task_struct * p)2257 static inline unsigned int task_cpu(const struct task_struct *p)
2258 {
2259 	return READ_ONCE(task_thread_info(p)->cpu);
2260 }
2261 
2262 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2263 
2264 #else
2265 
task_cpu(const struct task_struct * p)2266 static inline unsigned int task_cpu(const struct task_struct *p)
2267 {
2268 	return 0;
2269 }
2270 
set_task_cpu(struct task_struct * p,unsigned int cpu)2271 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2272 {
2273 }
2274 
2275 #endif /* CONFIG_SMP */
2276 
task_is_runnable(struct task_struct * p)2277 static inline bool task_is_runnable(struct task_struct *p)
2278 {
2279 	return p->on_rq && !p->se.sched_delayed;
2280 }
2281 
2282 extern bool sched_task_on_rq(struct task_struct *p);
2283 extern unsigned long get_wchan(struct task_struct *p);
2284 extern struct task_struct *cpu_curr_snapshot(int cpu);
2285 
2286 /*
2287  * In order to reduce various lock holder preemption latencies provide an
2288  * interface to see if a vCPU is currently running or not.
2289  *
2290  * This allows us to terminate optimistic spin loops and block, analogous to
2291  * the native optimistic spin heuristic of testing if the lock owner task is
2292  * running or not.
2293  */
2294 #ifndef vcpu_is_preempted
vcpu_is_preempted(int cpu)2295 static inline bool vcpu_is_preempted(int cpu)
2296 {
2297 	return false;
2298 }
2299 #endif
2300 
2301 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2302 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2303 
2304 #ifndef TASK_SIZE_OF
2305 #define TASK_SIZE_OF(tsk)	TASK_SIZE
2306 #endif
2307 
owner_on_cpu(struct task_struct * owner)2308 static inline bool owner_on_cpu(struct task_struct *owner)
2309 {
2310 	/*
2311 	 * As lock holder preemption issue, we both skip spinning if
2312 	 * task is not on cpu or its cpu is preempted
2313 	 */
2314 	return READ_ONCE(owner->on_cpu) && !vcpu_is_preempted(task_cpu(owner));
2315 }
2316 
2317 /* Returns effective CPU energy utilization, as seen by the scheduler */
2318 unsigned long sched_cpu_util(int cpu);
2319 
2320 #ifdef CONFIG_SCHED_CORE
2321 extern void sched_core_free(struct task_struct *tsk);
2322 extern void sched_core_fork(struct task_struct *p);
2323 extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type,
2324 				unsigned long uaddr);
2325 extern int sched_core_idle_cpu(int cpu);
2326 #else
sched_core_free(struct task_struct * tsk)2327 static inline void sched_core_free(struct task_struct *tsk) { }
sched_core_fork(struct task_struct * p)2328 static inline void sched_core_fork(struct task_struct *p) { }
sched_core_idle_cpu(int cpu)2329 static inline int sched_core_idle_cpu(int cpu) { return idle_cpu(cpu); }
2330 #endif
2331 
2332 extern void sched_set_stop_task(int cpu, struct task_struct *stop);
2333 
2334 #ifdef CONFIG_MEM_ALLOC_PROFILING
alloc_tag_save(struct alloc_tag * tag)2335 static __always_inline struct alloc_tag *alloc_tag_save(struct alloc_tag *tag)
2336 {
2337 	swap(current->alloc_tag, tag);
2338 	return tag;
2339 }
2340 
alloc_tag_restore(struct alloc_tag * tag,struct alloc_tag * old)2341 static __always_inline void alloc_tag_restore(struct alloc_tag *tag, struct alloc_tag *old)
2342 {
2343 #ifdef CONFIG_MEM_ALLOC_PROFILING_DEBUG
2344 	WARN(current->alloc_tag != tag, "current->alloc_tag was changed:\n");
2345 #endif
2346 	current->alloc_tag = old;
2347 }
2348 #else
2349 #define alloc_tag_save(_tag)			NULL
2350 #define alloc_tag_restore(_tag, _old)		do {} while (0)
2351 #endif
2352 
2353 /* Avoids recursive inclusion hell */
2354 #ifdef CONFIG_SCHED_MM_CID
2355 void sched_mm_cid_before_execve(struct task_struct *t);
2356 void sched_mm_cid_after_execve(struct task_struct *t);
2357 void sched_mm_cid_fork(struct task_struct *t);
2358 void sched_mm_cid_exit(struct task_struct *t);
task_mm_cid(struct task_struct * t)2359 static __always_inline int task_mm_cid(struct task_struct *t)
2360 {
2361 	return t->mm_cid.cid & ~(MM_CID_ONCPU | MM_CID_TRANSIT);
2362 }
2363 #else
sched_mm_cid_before_execve(struct task_struct * t)2364 static inline void sched_mm_cid_before_execve(struct task_struct *t) { }
sched_mm_cid_after_execve(struct task_struct * t)2365 static inline void sched_mm_cid_after_execve(struct task_struct *t) { }
sched_mm_cid_fork(struct task_struct * t)2366 static inline void sched_mm_cid_fork(struct task_struct *t) { }
sched_mm_cid_exit(struct task_struct * t)2367 static inline void sched_mm_cid_exit(struct task_struct *t) { }
task_mm_cid(struct task_struct * t)2368 static __always_inline int task_mm_cid(struct task_struct *t)
2369 {
2370 	/*
2371 	 * Use the processor id as a fall-back when the mm cid feature is
2372 	 * disabled. This provides functional per-cpu data structure accesses
2373 	 * in user-space, althrough it won't provide the memory usage benefits.
2374 	 */
2375 	return task_cpu(t);
2376 }
2377 #endif
2378 
2379 #ifndef MODULE
2380 #ifndef COMPILE_OFFSETS
2381 
2382 extern void ___migrate_enable(void);
2383 
2384 struct rq;
2385 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
2386 
2387 /*
2388  * The "struct rq" is not available here, so we can't access the
2389  * "runqueues" with this_cpu_ptr(), as the compilation will fail in
2390  * this_cpu_ptr() -> raw_cpu_ptr() -> __verify_pcpu_ptr():
2391  *   typeof((ptr) + 0)
2392  *
2393  * So use arch_raw_cpu_ptr()/PERCPU_PTR() directly here.
2394  */
2395 #ifdef CONFIG_SMP
2396 #define this_rq_raw() arch_raw_cpu_ptr(&runqueues)
2397 #else
2398 #define this_rq_raw() PERCPU_PTR(&runqueues)
2399 #endif
2400 #define this_rq_pinned() (*(unsigned int *)((void *)this_rq_raw() + RQ_nr_pinned))
2401 
__migrate_enable(void)2402 static inline void __migrate_enable(void)
2403 {
2404 	struct task_struct *p = current;
2405 
2406 #ifdef CONFIG_DEBUG_PREEMPT
2407 	/*
2408 	 * Check both overflow from migrate_disable() and superfluous
2409 	 * migrate_enable().
2410 	 */
2411 	if (WARN_ON_ONCE((s16)p->migration_disabled <= 0))
2412 		return;
2413 #endif
2414 
2415 	if (p->migration_disabled > 1) {
2416 		p->migration_disabled--;
2417 		return;
2418 	}
2419 
2420 	/*
2421 	 * Ensure stop_task runs either before or after this, and that
2422 	 * __set_cpus_allowed_ptr(SCA_MIGRATE_ENABLE) doesn't schedule().
2423 	 */
2424 	guard(preempt)();
2425 	if (unlikely(p->cpus_ptr != &p->cpus_mask))
2426 		___migrate_enable();
2427 	/*
2428 	 * Mustn't clear migration_disabled() until cpus_ptr points back at the
2429 	 * regular cpus_mask, otherwise things that race (eg.
2430 	 * select_fallback_rq) get confused.
2431 	 */
2432 	barrier();
2433 	p->migration_disabled = 0;
2434 	this_rq_pinned()--;
2435 }
2436 
__migrate_disable(void)2437 static inline void __migrate_disable(void)
2438 {
2439 	struct task_struct *p = current;
2440 
2441 	if (p->migration_disabled) {
2442 #ifdef CONFIG_DEBUG_PREEMPT
2443 		/*
2444 		 *Warn about overflow half-way through the range.
2445 		 */
2446 		WARN_ON_ONCE((s16)p->migration_disabled < 0);
2447 #endif
2448 		p->migration_disabled++;
2449 		return;
2450 	}
2451 
2452 	guard(preempt)();
2453 	this_rq_pinned()++;
2454 	p->migration_disabled = 1;
2455 }
2456 #else /* !COMPILE_OFFSETS */
__migrate_disable(void)2457 static inline void __migrate_disable(void) { }
__migrate_enable(void)2458 static inline void __migrate_enable(void) { }
2459 #endif /* !COMPILE_OFFSETS */
2460 
2461 /*
2462  * So that it is possible to not export the runqueues variable, define and
2463  * export migrate_enable/migrate_disable in kernel/sched/core.c too, and use
2464  * them for the modules. The macro "INSTANTIATE_EXPORTED_MIGRATE_DISABLE" will
2465  * be defined in kernel/sched/core.c.
2466  */
2467 #ifndef INSTANTIATE_EXPORTED_MIGRATE_DISABLE
migrate_disable(void)2468 static __always_inline void migrate_disable(void)
2469 {
2470 	__migrate_disable();
2471 }
2472 
migrate_enable(void)2473 static __always_inline void migrate_enable(void)
2474 {
2475 	__migrate_enable();
2476 }
2477 #else /* INSTANTIATE_EXPORTED_MIGRATE_DISABLE */
2478 extern void migrate_disable(void);
2479 extern void migrate_enable(void);
2480 #endif /* INSTANTIATE_EXPORTED_MIGRATE_DISABLE */
2481 
2482 #else /* MODULE */
2483 extern void migrate_disable(void);
2484 extern void migrate_enable(void);
2485 #endif /* MODULE */
2486 
2487 DEFINE_LOCK_GUARD_0(migrate, migrate_disable(), migrate_enable())
2488 
2489 #endif
2490