sched.h 54.4 KB
Newer Older
1
/* SPDX-License-Identifier: GPL-2.0 */
L
Linus Torvalds 已提交
2 3 4
#ifndef _LINUX_SCHED_H
#define _LINUX_SCHED_H

5 6 7 8
/*
 * Define 'struct task_struct' and provide the main scheduler
 * APIs (schedule(), wakeup variants, etc.)
 */
9

10
#include <uapi/linux/sched.h>
11

12
#include <asm/current.h>
L
Linus Torvalds 已提交
13

14
#include <linux/pid.h>
L
Linus Torvalds 已提交
15
#include <linux/sem.h>
16
#include <linux/shm.h>
17 18 19 20
#include <linux/kcov.h>
#include <linux/mutex.h>
#include <linux/plist.h>
#include <linux/hrtimer.h>
L
Linus Torvalds 已提交
21
#include <linux/seccomp.h>
22
#include <linux/nodemask.h>
23
#include <linux/rcupdate.h>
24
#include <linux/resource.h>
A
Arjan van de Ven 已提交
25
#include <linux/latencytop.h>
26 27 28 29
#include <linux/sched/prio.h>
#include <linux/signal_types.h>
#include <linux/mm_types_task.h>
#include <linux/task_io_accounting.h>
30
#include <linux/rseq.h>
31

32 33
#include <linux/ali_hotfix.h>

34
/* task_struct member predeclarations (sorted alphabetically): */
35 36
struct audit_context;
struct backing_dev_info;
37
struct bio_list;
38
struct blk_plug;
39 40 41 42 43
struct cfs_rq;
struct fs_struct;
struct futex_pi_state;
struct io_context;
struct mempolicy;
44
struct nameidata;
45 46 47 48 49 50
struct nsproxy;
struct perf_event_context;
struct pid_namespace;
struct pipe_inode_info;
struct rcu_node;
struct reclaim_state;
51
struct capture_control;
52 53 54
struct robust_list_head;
struct sched_attr;
struct sched_param;
I
Ingo Molnar 已提交
55
struct seq_file;
56 57 58
struct sighand_struct;
struct signal_struct;
struct task_delay_info;
59
struct task_group;
L
Linus Torvalds 已提交
60

61 62 63 64 65 66 67 68 69 70
/*
 * Task state bitmask. NOTE! These bits are also
 * encoded in fs/proc/array.c: get_task_state().
 *
 * We have two separate sets of flags: task->state
 * is about runnability, while task->exit_state are
 * about the task exiting. Confusing, but this way
 * modifying one set can't modify the other one by
 * mistake.
 */
71 72

/* Used in tsk->state: */
73 74 75 76 77
#define TASK_RUNNING			0x0000
#define TASK_INTERRUPTIBLE		0x0001
#define TASK_UNINTERRUPTIBLE		0x0002
#define __TASK_STOPPED			0x0004
#define __TASK_TRACED			0x0008
78
/* Used in tsk->exit_state: */
79 80
#define EXIT_DEAD			0x0010
#define EXIT_ZOMBIE			0x0020
81 82
#define EXIT_TRACE			(EXIT_ZOMBIE | EXIT_DEAD)
/* Used in tsk->state again: */
83 84 85 86
#define TASK_PARKED			0x0040
#define TASK_DEAD			0x0080
#define TASK_WAKEKILL			0x0100
#define TASK_WAKING			0x0200
87 88 89
#define TASK_NOLOAD			0x0400
#define TASK_NEW			0x0800
#define TASK_STATE_MAX			0x1000
90 91 92 93 94 95 96 97 98 99 100 101 102 103

/* Convenience macros for the sake of set_current_state: */
#define TASK_KILLABLE			(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
#define TASK_STOPPED			(TASK_WAKEKILL | __TASK_STOPPED)
#define TASK_TRACED			(TASK_WAKEKILL | __TASK_TRACED)

#define TASK_IDLE			(TASK_UNINTERRUPTIBLE | TASK_NOLOAD)

/* Convenience macros for the sake of wake_up(): */
#define TASK_NORMAL			(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)

/* get_task_state(): */
#define TASK_REPORT			(TASK_RUNNING | TASK_INTERRUPTIBLE | \
					 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
104 105
					 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \
					 TASK_PARKED)
106 107 108 109 110 111 112 113 114 115

#define task_is_traced(task)		((task->state & __TASK_TRACED) != 0)

#define task_is_stopped(task)		((task->state & __TASK_STOPPED) != 0)

#define task_is_stopped_or_traced(task)	((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)

#define task_contributes_to_load(task)	((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
					 (task->flags & PF_FROZEN) == 0 && \
					 (task->state & TASK_NOLOAD) == 0)
L
Linus Torvalds 已提交
116

P
Peter Zijlstra 已提交
117 118
#ifdef CONFIG_DEBUG_ATOMIC_SLEEP

119 120 121 122 123
/*
 * Special states are those that do not use the normal wait-loop pattern. See
 * the comment with set_special_state().
 */
#define is_special_task_state(state)				\
124
	((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | TASK_DEAD))
125

P
Peter Zijlstra 已提交
126 127
#define __set_current_state(state_value)			\
	do {							\
128
		WARN_ON_ONCE(is_special_task_state(state_value));\
P
Peter Zijlstra 已提交
129 130 131
		current->task_state_change = _THIS_IP_;		\
		current->state = (state_value);			\
	} while (0)
132

P
Peter Zijlstra 已提交
133 134
#define set_current_state(state_value)				\
	do {							\
135
		WARN_ON_ONCE(is_special_task_state(state_value));\
P
Peter Zijlstra 已提交
136
		current->task_state_change = _THIS_IP_;		\
137
		smp_store_mb(current->state, (state_value));	\
P
Peter Zijlstra 已提交
138 139
	} while (0)

140 141 142 143 144 145 146 147 148
#define set_special_state(state_value)					\
	do {								\
		unsigned long flags; /* may shadow */			\
		WARN_ON_ONCE(!is_special_task_state(state_value));	\
		raw_spin_lock_irqsave(&current->pi_lock, flags);	\
		current->task_state_change = _THIS_IP_;			\
		current->state = (state_value);				\
		raw_spin_unlock_irqrestore(&current->pi_lock, flags);	\
	} while (0)
P
Peter Zijlstra 已提交
149
#else
150 151 152 153 154
/*
 * set_current_state() includes a barrier so that the write of current->state
 * is correctly serialised wrt the caller's subsequent test of whether to
 * actually sleep:
 *
155
 *   for (;;) {
156
 *	set_current_state(TASK_UNINTERRUPTIBLE);
157 158 159 160 161 162 163 164 165 166 167 168 169
 *	if (!need_sleep)
 *		break;
 *
 *	schedule();
 *   }
 *   __set_current_state(TASK_RUNNING);
 *
 * If the caller does not need such serialisation (because, for instance, the
 * condition test and condition change and wakeup are under the same lock) then
 * use __set_current_state().
 *
 * The above is typically ordered against the wakeup, which does:
 *
170 171
 *   need_sleep = false;
 *   wake_up_state(p, TASK_UNINTERRUPTIBLE);
172
 *
173 174
 * where wake_up_state() executes a full memory barrier before accessing the
 * task state.
175 176 177 178
 *
 * Wakeup will do: if (@state & p->state) p->state = TASK_RUNNING, that is,
 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a
 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING).
179
 *
180 181 182 183
 * However, with slightly different timing the wakeup TASK_RUNNING store can
 * also collide with the TASK_UNINTERRUPTIBLE store. Loosing that store is not
 * a problem either because that will result in one extra go around the loop
 * and our @cond test will save the day.
184
 *
185
 * Also see the comments of try_to_wake_up().
186
 */
187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206
#define __set_current_state(state_value)				\
	current->state = (state_value)

#define set_current_state(state_value)					\
	smp_store_mb(current->state, (state_value))

/*
 * set_special_state() should be used for those states when the blocking task
 * can not use the regular condition based wait-loop. In that case we must
 * serialize against wakeups such that any possible in-flight TASK_RUNNING stores
 * will not collide with our state change.
 */
#define set_special_state(state_value)					\
	do {								\
		unsigned long flags; /* may shadow */			\
		raw_spin_lock_irqsave(&current->pi_lock, flags);	\
		current->state = (state_value);				\
		raw_spin_unlock_irqrestore(&current->pi_lock, flags);	\
	} while (0)

P
Peter Zijlstra 已提交
207 208
#endif

209 210
/* Task command name length: */
#define TASK_COMM_LEN			16
L
Linus Torvalds 已提交
211 212 213

extern void scheduler_tick(void);

214 215 216 217 218 219 220
#define	MAX_SCHEDULE_TIMEOUT		LONG_MAX

extern long schedule_timeout(long timeout);
extern long schedule_timeout_interruptible(long timeout);
extern long schedule_timeout_killable(long timeout);
extern long schedule_timeout_uninterruptible(long timeout);
extern long schedule_timeout_idle(long timeout);
L
Linus Torvalds 已提交
221
asmlinkage void schedule(void);
222
extern void schedule_preempt_disabled(void);
L
Linus Torvalds 已提交
223

224 225
extern int __must_check io_schedule_prepare(void);
extern void io_schedule_finish(int token);
226
extern long io_schedule_timeout(long timeout);
227
extern void io_schedule(void);
228

229
/**
230
 * struct prev_cputime - snapshot of system and user cputime
231 232
 * @utime: time spent in user mode
 * @stime: time spent in system mode
233
 * @lock: protects the above two fields
234
 *
235 236
 * Stores previous user/system time values such that we can guarantee
 * monotonicity.
237
 */
238 239
struct prev_cputime {
#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
240 241 242
	u64				utime;
	u64				stime;
	raw_spinlock_t			lock;
243
#endif
244 245
};

246 247
/**
 * struct task_cputime - collected CPU time counts
248 249
 * @utime:		time spent in user mode, in nanoseconds
 * @stime:		time spent in kernel mode, in nanoseconds
250
 * @sum_exec_runtime:	total time spent on the CPU, in nanoseconds
251
 *
252 253 254
 * This structure groups together three kinds of CPU time that are tracked for
 * threads and thread groups.  Most things considering CPU time want to group
 * these counts together and treat all three of them in parallel.
255 256
 */
struct task_cputime {
257 258 259
	u64				utime;
	u64				stime;
	unsigned long long		sum_exec_runtime;
260
};
261

262 263 264 265
/* Alternate field names when used on cache expirations: */
#define virt_exp			utime
#define prof_exp			stime
#define sched_exp			sum_exec_runtime
266

267 268 269 270 271 272 273 274 275 276 277 278 279
enum vtime_state {
	/* Task is sleeping or running in a CPU with VTIME inactive: */
	VTIME_INACTIVE = 0,
	/* Task runs in userspace in a CPU with VTIME active: */
	VTIME_USER,
	/* Task runs in kernelspace in a CPU with VTIME active: */
	VTIME_SYS,
};

struct vtime {
	seqcount_t		seqcount;
	unsigned long long	starttime;
	enum vtime_state	state;
280 281 282
	u64			utime;
	u64			stime;
	u64			gtime;
283 284
};

L
Linus Torvalds 已提交
285
struct sched_info {
286
#ifdef CONFIG_SCHED_INFO
287 288 289 290 291 292 293 294 295 296 297 298 299 300 301
	/* Cumulative counters: */

	/* # of times we have run on this CPU: */
	unsigned long			pcount;

	/* Time spent waiting on a runqueue: */
	unsigned long long		run_delay;

	/* Timestamps: */

	/* When did we last run on a CPU? */
	unsigned long long		last_arrival;

	/* When were we last queued to run? */
	unsigned long long		last_queued;
L
Linus Torvalds 已提交
302

303
#endif /* CONFIG_SCHED_INFO */
304
};
L
Linus Torvalds 已提交
305

306 307 308 309 310 311 312
/*
 * Integer metrics need fixed point arithmetic, e.g., sched/fair
 * has a few: load, load_avg, util_avg, freq, and capacity.
 *
 * We define a basic fixed point arithmetic range, and then formalize
 * all these metrics based on that basic range.
 */
313 314
# define SCHED_FIXEDPOINT_SHIFT		10
# define SCHED_FIXEDPOINT_SCALE		(1L << SCHED_FIXEDPOINT_SHIFT)
315

I
Ingo Molnar 已提交
316
struct load_weight {
317 318
	unsigned long			weight;
	u32				inv_weight;
I
Ingo Molnar 已提交
319 320
};

321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346
/**
 * struct util_est - Estimation utilization of FAIR tasks
 * @enqueued: instantaneous estimated utilization of a task/cpu
 * @ewma:     the Exponential Weighted Moving Average (EWMA)
 *            utilization of a task
 *
 * Support data structure to track an Exponential Weighted Moving Average
 * (EWMA) of a FAIR task's utilization. New samples are added to the moving
 * average each time a task completes an activation. Sample's weight is chosen
 * so that the EWMA will be relatively insensitive to transient changes to the
 * task's workload.
 *
 * The enqueued attribute has a slightly different meaning for tasks and cpus:
 * - task:   the task's util_avg at last task dequeue time
 * - cfs_rq: the sum of util_est.enqueued for each RUNNABLE task on that CPU
 * Thus, the util_est.enqueued of a task represents the contribution on the
 * estimated utilization of the CPU where that task is currently enqueued.
 *
 * Only for tasks we track a moving average of the past instantaneous
 * estimated utilization. This allows to absorb sporadic drops in utilization
 * of an otherwise almost periodic task.
 */
struct util_est {
	unsigned int			enqueued;
	unsigned int			ewma;
#define UTIL_EST_WEIGHT_SHIFT		2
347
} __attribute__((__aligned__(sizeof(u64))));
348

349
/*
350 351 352 353 354 355 356 357 358
 * The load_avg/util_avg accumulates an infinite geometric series
 * (see __update_load_avg() in kernel/sched/fair.c).
 *
 * [load_avg definition]
 *
 *   load_avg = runnable% * scale_load_down(load)
 *
 * where runnable% is the time ratio that a sched_entity is runnable.
 * For cfs_rq, it is the aggregated load_avg of all runnable and
359
 * blocked sched_entities.
360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399
 *
 * load_avg may also take frequency scaling into account:
 *
 *   load_avg = runnable% * scale_load_down(load) * freq%
 *
 * where freq% is the CPU frequency normalized to the highest frequency.
 *
 * [util_avg definition]
 *
 *   util_avg = running% * SCHED_CAPACITY_SCALE
 *
 * where running% is the time ratio that a sched_entity is running on
 * a CPU. For cfs_rq, it is the aggregated util_avg of all runnable
 * and blocked sched_entities.
 *
 * util_avg may also factor frequency scaling and CPU capacity scaling:
 *
 *   util_avg = running% * SCHED_CAPACITY_SCALE * freq% * capacity%
 *
 * where freq% is the same as above, and capacity% is the CPU capacity
 * normalized to the greatest capacity (due to uarch differences, etc).
 *
 * N.B., the above ratios (runnable%, running%, freq%, and capacity%)
 * themselves are in the range of [0, 1]. To do fixed point arithmetics,
 * we therefore scale them to as large a range as necessary. This is for
 * example reflected by util_avg's SCHED_CAPACITY_SCALE.
 *
 * [Overflow issue]
 *
 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
 * with the highest load (=88761), always runnable on a single cfs_rq,
 * and should not overflow as the number already hits PID_MAX_LIMIT.
 *
 * For all other cases (including 32-bit kernels), struct load_weight's
 * weight will overflow first before we do, because:
 *
 *    Max(load_avg) <= Max(load.weight)
 *
 * Then it is the load_weight's responsibility to consider overflow
 * issues.
400
 */
401
struct sched_avg {
402 403
	u64				last_update_time;
	u64				load_sum;
404
	u64				runnable_load_sum;
405 406 407
	u32				util_sum;
	u32				period_contrib;
	unsigned long			load_avg;
408
	unsigned long			runnable_load_avg;
409
	unsigned long			util_avg;
410
	struct util_est			util_est;
411
} ____cacheline_aligned;
412

413
struct sched_statistics {
414
#ifdef CONFIG_SCHEDSTATS
415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445
	u64				wait_start;
	u64				wait_max;
	u64				wait_count;
	u64				wait_sum;
	u64				iowait_count;
	u64				iowait_sum;

	u64				sleep_start;
	u64				sleep_max;
	s64				sum_sleep_runtime;

	u64				block_start;
	u64				block_max;
	u64				exec_max;
	u64				slice_max;

	u64				nr_migrations_cold;
	u64				nr_failed_migrations_affine;
	u64				nr_failed_migrations_running;
	u64				nr_failed_migrations_hot;
	u64				nr_forced_migrations;

	u64				nr_wakeups;
	u64				nr_wakeups_sync;
	u64				nr_wakeups_migrate;
	u64				nr_wakeups_local;
	u64				nr_wakeups_remote;
	u64				nr_wakeups_affine;
	u64				nr_wakeups_affine_attempts;
	u64				nr_wakeups_passive;
	u64				nr_wakeups_idle;
446 447 448

	ALI_HOTFIX_RESERVE(1)
	ALI_HOTFIX_RESERVE(2)
449
#endif
450
};
451 452

struct sched_entity {
453 454
	/* For load-balancing: */
	struct load_weight		load;
455
	unsigned long			runnable_weight;
456 457 458
	struct rb_node			run_node;
	struct list_head		group_node;
	unsigned int			on_rq;
459

460 461 462 463
	u64				exec_start;
	u64				sum_exec_runtime;
	u64				vruntime;
	u64				prev_sum_exec_runtime;
464

465 466 467
	/* irq time is included */
	u64				exec_start_raw;
	u64				sum_exec_raw;
468 469
	u64				cg_idle_start;
	u64				cg_idle_sum;
470
	u64				cg_init_time;
471 472 473
	u64				cg_nr_iowait;
	u64				cg_iowait_sum;
	u64				cg_iowait_start;
474 475
	u64				cg_ineffective_sum;
	u64				cg_ineffective_start;
476
	seqcount_t			idle_seqcount;
477
	spinlock_t			iowait_lock;
478

479
	u64				nr_migrations;
480

481
	struct sched_statistics		statistics;
482

I
Ingo Molnar 已提交
483
#ifdef CONFIG_FAIR_GROUP_SCHED
484 485
	int				depth;
	struct sched_entity		*parent;
I
Ingo Molnar 已提交
486
	/* rq on which this entity is (to be) queued: */
487
	struct cfs_rq			*cfs_rq;
I
Ingo Molnar 已提交
488
	/* rq "owned" by this entity/group: */
489
	struct cfs_rq			*my_q;
I
Ingo Molnar 已提交
490
#endif
491

492
#ifdef CONFIG_SMP
493 494 495 496 497 498
	/*
	 * Per entity load average tracking.
	 *
	 * Put into separate cache line so it does not
	 * collide with read-mostly values above.
	 */
499
	struct sched_avg		avg;
500
#endif
501 502 503

	ALI_HOTFIX_RESERVE(1)
	ALI_HOTFIX_RESERVE(2)
I
Ingo Molnar 已提交
504
};
505

P
Peter Zijlstra 已提交
506
struct sched_rt_entity {
507 508 509 510 511 512 513 514
	struct list_head		run_list;
	unsigned long			timeout;
	unsigned long			watchdog_stamp;
	unsigned int			time_slice;
	unsigned short			on_rq;
	unsigned short			on_list;

	struct sched_rt_entity		*back;
515
#ifdef CONFIG_RT_GROUP_SCHED
516
	struct sched_rt_entity		*parent;
P
Peter Zijlstra 已提交
517
	/* rq on which this entity is (to be) queued: */
518
	struct rt_rq			*rt_rq;
P
Peter Zijlstra 已提交
519
	/* rq "owned" by this entity/group: */
520
	struct rt_rq			*my_q;
P
Peter Zijlstra 已提交
521
#endif
522
} __randomize_layout;
P
Peter Zijlstra 已提交
523

524
struct sched_dl_entity {
525
	struct rb_node			rb_node;
526 527 528

	/*
	 * Original scheduling parameters. Copied here from sched_attr
529 530
	 * during sched_setattr(), they will remain the same until
	 * the next sched_setattr().
531
	 */
532 533 534
	u64				dl_runtime;	/* Maximum runtime for each instance	*/
	u64				dl_deadline;	/* Relative deadline of each instance	*/
	u64				dl_period;	/* Separation of two instances (period) */
535
	u64				dl_bw;		/* dl_runtime / dl_period		*/
536
	u64				dl_density;	/* dl_runtime / dl_deadline		*/
537 538 539 540 541 542

	/*
	 * Actual scheduling parameters. Initialized with the values above,
	 * they are continously updated during task execution. Note that
	 * the remaining runtime could be < 0 in case we are in overrun.
	 */
543 544 545
	s64				runtime;	/* Remaining runtime for this instance	*/
	u64				deadline;	/* Absolute deadline for this instance	*/
	unsigned int			flags;		/* Specifying the scheduler behaviour	*/
546 547 548 549 550 551 552 553

	/*
	 * Some bool flags:
	 *
	 * @dl_throttled tells if we exhausted the runtime. If so, the
	 * task has to wait for a replenishment to be performed at the
	 * next firing of dl_timer.
	 *
554 555
	 * @dl_boosted tells if we are boosted due to DI. If so we are
	 * outside bandwidth enforcement mechanism (but only until we
556 557
	 * exit the critical section);
	 *
558
	 * @dl_yielded tells if task gave up the CPU before consuming
559
	 * all its available runtime during the last job.
560 561 562 563 564 565 566
	 *
	 * @dl_non_contending tells if the task is inactive while still
	 * contributing to the active utilization. In other words, it
	 * indicates if the inactive timer has been armed and its handler
	 * has not been executed yet. This flag is useful to avoid race
	 * conditions between the inactive timer handler and the wakeup
	 * code.
567 568 569
	 *
	 * @dl_overrun tells if the task asked to be informed about runtime
	 * overruns.
570
	 */
571 572 573 574
	unsigned int			dl_throttled      : 1;
	unsigned int			dl_boosted        : 1;
	unsigned int			dl_yielded        : 1;
	unsigned int			dl_non_contending : 1;
575
	unsigned int			dl_overrun	  : 1;
576 577 578 579 580

	/*
	 * Bandwidth enforcement timer. Each -deadline task has its
	 * own bandwidth to be enforced, thus we need one timer per task.
	 */
581
	struct hrtimer			dl_timer;
582 583 584 585 586 587 588 589 590

	/*
	 * Inactive timer, responsible for decreasing the active utilization
	 * at the "0-lag time". When a -deadline task blocks, it contributes
	 * to GRUB's active utilization until the "0-lag time", hence a
	 * timer is needed to decrease the active utilization at the correct
	 * time.
	 */
	struct hrtimer inactive_timer;
591
};
592

593 594
union rcu_special {
	struct {
595 596 597 598 599 600
		u8			blocked;
		u8			need_qs;
		u8			exp_need_qs;

		/* Otherwise the compiler can store garbage here: */
		u8			pad;
601 602
	} b; /* Bits. */
	u32 s; /* Set of bits. */
603
};
604

P
Peter Zijlstra 已提交
605 606 607
enum perf_event_task_context {
	perf_invalid_context = -1,
	perf_hw_context = 0,
608
	perf_sw_context,
P
Peter Zijlstra 已提交
609 610 611
	perf_nr_task_contexts,
};

612 613 614 615
struct wake_q_node {
	struct wake_q_node *next;
};

L
Linus Torvalds 已提交
616
struct task_struct {
617 618 619 620 621
#ifdef CONFIG_THREAD_INFO_IN_TASK
	/*
	 * For reasons of header soup (see current_thread_info()), this
	 * must be the first element of task_struct.
	 */
622
	struct thread_info		thread_info;
623
#endif
624 625
	/* -1 unrunnable, 0 runnable, >0 stopped: */
	volatile long			state;
K
Kees Cook 已提交
626 627 628 629 630 631 632

	/*
	 * This begins the randomizable portion of task_struct. Only
	 * scheduling-critical items should be added above here.
	 */
	randomized_struct_fields_start

633 634 635 636 637
	void				*stack;
	atomic_t			usage;
	/* Per task flags (PF_*), defined further below: */
	unsigned int			flags;
	unsigned int			ptrace;
L
Linus Torvalds 已提交
638

639
#ifdef CONFIG_SMP
640 641
	struct llist_node		wake_entry;
	int				on_cpu;
642
#ifdef CONFIG_THREAD_INFO_IN_TASK
643 644
	/* Current CPU: */
	unsigned int			cpu;
645
#endif
646 647 648
	unsigned int			wakee_flips;
	unsigned long			wakee_flip_decay_ts;
	struct task_struct		*last_wakee;
649

650 651 652 653 654 655 656 657
	/*
	 * recent_used_cpu is initially set as the last CPU used by a task
	 * that wakes affine another task. Waker/wakee relationships can
	 * push tasks around a CPU where each wakeup moves to the next one.
	 * Tracking a recently used CPU allows a quick search for a recently
	 * used CPU that may be idle.
	 */
	int				recent_used_cpu;
658
	int				wake_cpu;
659
#endif
660 661 662 663 664 665
	int				on_rq;

	int				prio;
	int				static_prio;
	int				normal_prio;
	unsigned int			rt_priority;
666

667 668 669
	const struct sched_class	*sched_class;
	struct sched_entity		se;
	struct sched_rt_entity		rt;
P
Peter Zijlstra 已提交
670
#ifdef CONFIG_CGROUP_SCHED
671
	struct task_group		*sched_task_group;
P
Peter Zijlstra 已提交
672
#endif
673
	struct sched_dl_entity		dl;
L
Linus Torvalds 已提交
674

675
#ifdef CONFIG_PREEMPT_NOTIFIERS
676 677
	/* List of struct preempt_notifier: */
	struct hlist_head		preempt_notifiers;
678 679
#endif

680
#ifdef CONFIG_BLK_DEV_IO_TRACE
681
	unsigned int			btrace_seq;
682
#endif
L
Linus Torvalds 已提交
683

684 685 686
	unsigned int			policy;
	int				nr_cpus_allowed;
	cpumask_t			cpus_allowed;
L
Linus Torvalds 已提交
687

P
Paul E. McKenney 已提交
688
#ifdef CONFIG_PREEMPT_RCU
689 690 691 692
	int				rcu_read_lock_nesting;
	union rcu_special		rcu_read_unlock_special;
	struct list_head		rcu_node_entry;
	struct rcu_node			*rcu_blocked_node;
693
#endif /* #ifdef CONFIG_PREEMPT_RCU */
694

P
Paul E. McKenney 已提交
695
#ifdef CONFIG_TASKS_RCU
696
	unsigned long			rcu_tasks_nvcsw;
697 698
	u8				rcu_tasks_holdout;
	u8				rcu_tasks_idx;
699
	int				rcu_tasks_idle_cpu;
700
	struct list_head		rcu_tasks_holdout_list;
P
Paul E. McKenney 已提交
701
#endif /* #ifdef CONFIG_TASKS_RCU */
P
Paul E. McKenney 已提交
702

703
	struct sched_info		sched_info;
L
Linus Torvalds 已提交
704

705
	struct list_head		tasks;
706
#ifdef CONFIG_SMP
707 708
	struct plist_node		pushable_tasks;
	struct rb_node			pushable_dl_tasks;
709
#endif
L
Linus Torvalds 已提交
710

711 712
	struct mm_struct		*mm;
	struct mm_struct		*active_mm;
713 714

	/* Per-thread vma caching: */
715
	struct vmacache			vmacache;
716

717 718
#ifdef SPLIT_RSS_COUNTING
	struct task_rss_stat		rss_stat;
719
#endif
720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735
	int				exit_state;
	int				exit_code;
	int				exit_signal;
	/* The signal sent when the parent dies: */
	int				pdeath_signal;
	/* JOBCTL_*, siglock protected: */
	unsigned long			jobctl;

	/* Used for emulating ABI behavior of previous Linux versions: */
	unsigned int			personality;

	/* Scheduler bits, serialized by scheduler locks: */
	unsigned			sched_reset_on_fork:1;
	unsigned			sched_contributes_to_load:1;
	unsigned			sched_migrated:1;
	unsigned			sched_remote_wakeup:1;
736 737 738 739
#ifdef CONFIG_PSI
	unsigned			sched_psi_wake_requeue:1;
#endif

740 741 742 743 744 745 746 747 748 749
	/* Force alignment to the next boundary: */
	unsigned			:0;

	/* Unserialized, strictly 'current' */

	/* Bit to tell LSMs we're in execve(): */
	unsigned			in_execve:1;
	unsigned			in_iowait:1;
#ifndef TIF_RESTORE_SIGMASK
	unsigned			restore_sigmask:1;
750
#endif
T
Tejun Heo 已提交
751
#ifdef CONFIG_MEMCG
752
	unsigned			in_user_fault:1;
753
#ifdef CONFIG_MEMCG_KMEM
754
	unsigned			memcg_kmem_skip_account:1;
755
#endif
756
#endif
757
#ifdef CONFIG_COMPAT_BRK
758
	unsigned			brk_randomized:1;
759
#endif
760 761 762 763
#ifdef CONFIG_CGROUPS
	/* disallow userland-initiated cgroup migration */
	unsigned			no_cgroup_migration:1;
#endif
764 765 766
#ifdef CONFIG_BLK_CGROUP
	unsigned			use_memdelay:1;
#endif
767 768 769 770
#ifdef CONFIG_PSI
       /* Stalled due to lack of memory */
       unsigned                        in_memstall:1;
#endif
771

772
	unsigned long			atomic_flags; /* Flags requiring atomic access. */
773

774
	struct restart_block		restart_block;
775

776 777
	pid_t				pid;
	pid_t				tgid;
778

779
#ifdef CONFIG_STACKPROTECTOR
780 781
	/* Canary value for the -fstack-protector GCC feature: */
	unsigned long			stack_canary;
782
#endif
783
	/*
784
	 * Pointers to the (original) parent process, youngest child, younger sibling,
785
	 * older sibling, respectively.  (p->father can be replaced with
R
Roland McGrath 已提交
786
	 * p->real_parent->pid)
L
Linus Torvalds 已提交
787
	 */
788 789 790 791 792 793 794

	/* Real parent process: */
	struct task_struct __rcu	*real_parent;

	/* Recipient of SIGCHLD, wait4() reports: */
	struct task_struct __rcu	*parent;

L
Linus Torvalds 已提交
795
	/*
796
	 * Children/sibling form the list of natural children:
L
Linus Torvalds 已提交
797
	 */
798 799 800
	struct list_head		children;
	struct list_head		sibling;
	struct task_struct		*group_leader;
L
Linus Torvalds 已提交
801

R
Roland McGrath 已提交
802
	/*
803 804
	 * 'ptraced' is the list of tasks this task is using ptrace() on.
	 *
R
Roland McGrath 已提交
805
	 * This includes both natural children and PTRACE_ATTACH targets.
806
	 * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
R
Roland McGrath 已提交
807
	 */
808 809
	struct list_head		ptraced;
	struct list_head		ptrace_entry;
R
Roland McGrath 已提交
810

L
Linus Torvalds 已提交
811
	/* PID/PID hash table linkage. */
812 813
	struct pid			*thread_pid;
	struct hlist_node		pid_links[PIDTYPE_MAX];
814 815 816 817
	struct list_head		thread_group;
	struct list_head		thread_node;

	struct completion		*vfork_done;
L
Linus Torvalds 已提交
818

819 820
	/* CLONE_CHILD_SETTID: */
	int __user			*set_child_tid;
L
Linus Torvalds 已提交
821

822 823 824 825 826
	/* CLONE_CHILD_CLEARTID: */
	int __user			*clear_child_tid;

	u64				utime;
	u64				stime;
827
#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
828 829
	u64				utimescaled;
	u64				stimescaled;
830
#endif
831 832
	u64				gtime;
	struct prev_cputime		prev_cputime;
833
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
834
	struct vtime			vtime;
835
#endif
836 837

#ifdef CONFIG_NO_HZ_FULL
838
	atomic_t			tick_dep_mask;
839
#endif
840 841 842 843 844 845 846 847 848 849 850 851 852
	/* Context switch counts: */
	unsigned long			nvcsw;
	unsigned long			nivcsw;

	/* Monotonic time in nsecs: */
	u64				start_time;

	/* Boot based time in nsecs: */
	u64				real_start_time;

	/* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
	unsigned long			min_flt;
	unsigned long			maj_flt;
L
Linus Torvalds 已提交
853

854
#ifdef CONFIG_POSIX_TIMERS
855 856
	struct task_cputime		cputime_expires;
	struct list_head		cpu_timers[3];
857
#endif
L
Linus Torvalds 已提交
858

859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880
	/* Process credentials: */

	/* Tracer's credentials at attach: */
	const struct cred __rcu		*ptracer_cred;

	/* Objective and real subjective task credentials (COW): */
	const struct cred __rcu		*real_cred;

	/* Effective (overridable) subjective task credentials (COW): */
	const struct cred __rcu		*cred;

	/*
	 * executable name, excluding path.
	 *
	 * - normally initialized setup_new_exec()
	 * - access it with [gs]et_task_comm()
	 * - lock it with task_lock()
	 */
	char				comm[TASK_COMM_LEN];

	struct nameidata		*nameidata;

881
#ifdef CONFIG_SYSVIPC
882 883
	struct sysv_sem			sysvsem;
	struct sysv_shm			sysvshm;
884
#endif
885
#ifdef CONFIG_DETECT_HUNG_TASK
886
	unsigned long			last_switch_count;
887
	unsigned long			last_switch_time;
888
#endif
889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912
	/* Filesystem information: */
	struct fs_struct		*fs;

	/* Open file information: */
	struct files_struct		*files;

	/* Namespaces: */
	struct nsproxy			*nsproxy;

	/* Signal handlers: */
	struct signal_struct		*signal;
	struct sighand_struct		*sighand;
	sigset_t			blocked;
	sigset_t			real_blocked;
	/* Restored if set_restore_sigmask() was used: */
	sigset_t			saved_sigmask;
	struct sigpending		pending;
	unsigned long			sas_ss_sp;
	size_t				sas_ss_size;
	unsigned int			sas_ss_flags;

	struct callback_head		*task_works;

	struct audit_context		*audit_context;
A
Al Viro 已提交
913
#ifdef CONFIG_AUDITSYSCALL
914 915
	kuid_t				loginuid;
	unsigned int			sessionid;
A
Al Viro 已提交
916
#endif
917 918 919 920 921
	struct seccomp			seccomp;

	/* Thread group tracking: */
	u32				parent_exec_id;
	u32				self_exec_id;
L
Linus Torvalds 已提交
922

923 924
	/* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
	spinlock_t			alloc_lock;
L
Linus Torvalds 已提交
925

926
	/* Protection of the PI data structures: */
927
	raw_spinlock_t			pi_lock;
928

929
	struct wake_q_node		wake_q;
930

I
Ingo Molnar 已提交
931
#ifdef CONFIG_RT_MUTEXES
932
	/* PI waiters blocked on a rt_mutex held by this task: */
933
	struct rb_root_cached		pi_waiters;
934 935
	/* Updated under owner's pi_lock and rq lock */
	struct task_struct		*pi_top_task;
936 937
	/* Deadlock detection and priority inheritance handling: */
	struct rt_mutex_waiter		*pi_blocked_on;
I
Ingo Molnar 已提交
938 939
#endif

940
#ifdef CONFIG_DEBUG_MUTEXES
941 942
	/* Mutex deadlock detection: */
	struct mutex_waiter		*blocked_on;
943
#endif
944

945
#ifdef CONFIG_TRACE_IRQFLAGS
946 947 948 949 950 951 952 953 954 955 956 957 958
	unsigned int			irq_events;
	unsigned long			hardirq_enable_ip;
	unsigned long			hardirq_disable_ip;
	unsigned int			hardirq_enable_event;
	unsigned int			hardirq_disable_event;
	int				hardirqs_enabled;
	int				hardirq_context;
	unsigned long			softirq_disable_ip;
	unsigned long			softirq_enable_ip;
	unsigned int			softirq_disable_event;
	unsigned int			softirq_enable_event;
	int				softirqs_enabled;
	int				softirq_context;
959
#endif
960

I
Ingo Molnar 已提交
961
#ifdef CONFIG_LOCKDEP
962 963 964 965 966
# define MAX_LOCK_DEPTH			48UL
	u64				curr_chain_key;
	int				lockdep_depth;
	unsigned int			lockdep_recursion;
	struct held_lock		held_locks[MAX_LOCK_DEPTH];
I
Ingo Molnar 已提交
967
#endif
968

969
#ifdef CONFIG_UBSAN
970
	unsigned int			in_ubsan;
971
#endif
972

973 974
	/* Journalling filesystem info: */
	void				*journal_info;
L
Linus Torvalds 已提交
975

976 977
	/* Stacked block device info: */
	struct bio_list			*bio_list;
978

979
#ifdef CONFIG_BLOCK
980 981
	/* Stack plugging: */
	struct blk_plug			*plug;
982 983
#endif

984 985 986 987
	/* VM state: */
	struct reclaim_state		*reclaim_state;

	struct backing_dev_info		*backing_dev_info;
L
Linus Torvalds 已提交
988

989
	struct io_context		*io_context;
L
Linus Torvalds 已提交
990

991 992 993
#ifdef CONFIG_COMPACTION
	struct capture_control		*capture_control;
#endif
994 995 996
	/* Ptrace state: */
	unsigned long			ptrace_message;
	siginfo_t			*last_siginfo;
L
Linus Torvalds 已提交
997

998
	struct task_io_accounting	ioac;
999 1000 1001 1002
#ifdef CONFIG_PSI
	/* Pressure stall state */
	unsigned int			psi_flags;
#endif
1003 1004 1005 1006 1007 1008 1009
#ifdef CONFIG_TASK_XACCT
	/* Accumulated RSS usage: */
	u64				acct_rss_mem1;
	/* Accumulated virtual memory usage: */
	u64				acct_vm_mem1;
	/* stime + utime since last update: */
	u64				acct_timexpd;
L
Linus Torvalds 已提交
1010 1011
#endif
#ifdef CONFIG_CPUSETS
1012 1013 1014 1015 1016 1017
	/* Protected by ->alloc_lock: */
	nodemask_t			mems_allowed;
	/* Seqence number to catch updates: */
	seqcount_t			mems_allowed_seq;
	int				cpuset_mem_spread_rotor;
	int				cpuset_slab_spread_rotor;
L
Linus Torvalds 已提交
1018
#endif
1019
#ifdef CONFIG_CGROUPS
1020 1021 1022 1023
	/* Control Group info protected by css_set_lock: */
	struct css_set __rcu		*cgroups;
	/* cg_list protected by css_set_lock and tsk->alloc_lock: */
	struct list_head		cg_list;
1024
#endif
1025
#ifdef CONFIG_RESCTRL
1026
	u32				closid;
1027
	u32				rmid;
F
Fenghua Yu 已提交
1028
#endif
1029
#ifdef CONFIG_FUTEX
1030
	struct robust_list_head __user	*robust_list;
1031 1032 1033
#ifdef CONFIG_COMPAT
	struct compat_robust_list_head __user *compat_robust_list;
#endif
1034 1035
	struct list_head		pi_state_list;
	struct futex_pi_state		*pi_state_cache;
1036
#endif
1037
#ifdef CONFIG_PERF_EVENTS
1038 1039 1040
	struct perf_event_context	*perf_event_ctxp[perf_nr_task_contexts];
	struct mutex			perf_event_mutex;
	struct list_head		perf_event_list;
1041
#endif
1042
#ifdef CONFIG_DEBUG_PREEMPT
1043
	unsigned long			preempt_disable_ip;
1044
#endif
1045
#ifdef CONFIG_NUMA
1046 1047
	/* Protected by alloc_lock: */
	struct mempolicy		*mempolicy;
1048
	short				il_prev;
1049
	short				pref_node_fork;
1050
#endif
1051
#ifdef CONFIG_NUMA_BALANCING
1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062
	int				numa_scan_seq;
	unsigned int			numa_scan_period;
	unsigned int			numa_scan_period_max;
	int				numa_preferred_nid;
	unsigned long			numa_migrate_retry;
	/* Migration stamp: */
	u64				node_stamp;
	u64				last_task_numa_placement;
	u64				last_sum_exec_runtime;
	struct callback_head		numa_work;

1063 1064 1065 1066 1067 1068 1069 1070 1071
	/*
	 * This pointer is only modified for current in syscall and
	 * pagefault context (and for tasks being destroyed), so it can be read
	 * from any of the following contexts:
	 *  - RCU read-side critical section
	 *  - current->numa_group from everywhere
	 *  - task's runqueue locked, task not running
	 */
	struct numa_group __rcu		*numa_group;
1072

1073
	/*
1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085
	 * numa_faults is an array split into four regions:
	 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
	 * in this precise order.
	 *
	 * faults_memory: Exponential decaying average of faults on a per-node
	 * basis. Scheduling placement decisions are made based on these
	 * counts. The values remain static for the duration of a PTE scan.
	 * faults_cpu: Track the nodes the process was running on when a NUMA
	 * hinting fault was incurred.
	 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
	 * during the current scan window. When the scan completes, the counts
	 * in faults_memory and faults_cpu decay and these values are copied.
1086
	 */
1087 1088
	unsigned long			*numa_faults;
	unsigned long			total_numa_faults;
1089

1090 1091
	/*
	 * numa_faults_locality tracks if faults recorded during the last
1092 1093 1094
	 * scan window were remote/local or failed to migrate. The task scan
	 * period is adapted based on the locality of the faults with different
	 * weights depending on whether they were shared or private faults
1095
	 */
1096
	unsigned long			numa_faults_locality[3];
1097

1098
	unsigned long			numa_pages_migrated;
1099 1100
#endif /* CONFIG_NUMA_BALANCING */

1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111
#ifdef CONFIG_RSEQ
	struct rseq __user *rseq;
	u32 rseq_len;
	u32 rseq_sig;
	/*
	 * RmW on rseq_event_mask must be performed atomically
	 * with respect to preemption.
	 */
	unsigned long rseq_event_mask;
#endif

1112
	struct tlbflush_unmap_batch	tlb_ubc;
1113

1114
	struct rcu_head			rcu;
1115

1116 1117
	/* Cache last used pipe for splice(): */
	struct pipe_inode_info		*splice_pipe;
1118

1119
	struct page_frag		task_frag;
1120

1121 1122
#ifdef CONFIG_TASK_DELAY_ACCT
	struct task_delay_info		*delays;
1123
#endif
1124

1125
#ifdef CONFIG_FAULT_INJECTION
1126
	int				make_it_fail;
1127
	unsigned int			fail_nth;
1128
#endif
1129
	/*
1130 1131
	 * When (nr_dirtied >= nr_dirtied_pause), it's time to call
	 * balance_dirty_pages() for a dirty throttling pause:
1132
	 */
1133 1134 1135 1136
	int				nr_dirtied;
	int				nr_dirtied_pause;
	/* Start of a write-and-pause period: */
	unsigned long			dirty_paused_when;
1137

A
Arjan van de Ven 已提交
1138
#ifdef CONFIG_LATENCYTOP
1139 1140
	int				latency_record_count;
	struct latency_record		latency_record[LT_SAVECOUNT];
A
Arjan van de Ven 已提交
1141
#endif
1142
	/*
1143
	 * Time slack values; these are used to round up poll() and
1144 1145
	 * select() etc timeout values. These are in nanoseconds.
	 */
1146 1147
	u64				timer_slack_ns;
	u64				default_timer_slack_ns;
1148

1149
#ifdef CONFIG_KASAN
1150
	unsigned int			kasan_depth;
1151
#endif
1152

1153
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1154 1155
	/* Index of current stored address in ret_stack: */
	int				curr_ret_stack;
1156
	int				curr_ret_depth;
1157 1158 1159 1160 1161 1162 1163

	/* Stack of return addresses for return function tracing: */
	struct ftrace_ret_stack		*ret_stack;

	/* Timestamp for last schedule: */
	unsigned long long		ftrace_timestamp;

1164 1165
	/*
	 * Number of functions that haven't been traced
1166
	 * because of depth overrun:
1167
	 */
1168 1169 1170 1171
	atomic_t			trace_overrun;

	/* Pause tracing: */
	atomic_t			tracing_graph_pause;
1172
#endif
1173

1174
#ifdef CONFIG_TRACING
1175 1176 1177 1178 1179
	/* State flags for use by tracers: */
	unsigned long			trace;

	/* Bitmask and counter of trace recursion: */
	unsigned long			trace_recursion;
1180
#endif /* CONFIG_TRACING */
1181

D
Dmitry Vyukov 已提交
1182
#ifdef CONFIG_KCOV
1183
	/* Coverage collection mode enabled for this task (0 if disabled): */
1184
	unsigned int			kcov_mode;
1185 1186 1187 1188 1189 1190 1191 1192 1193

	/* Size of the kcov_area: */
	unsigned int			kcov_size;

	/* Buffer for coverage collection: */
	void				*kcov_area;

	/* KCOV descriptor wired with this task or NULL: */
	struct kcov			*kcov;
D
Dmitry Vyukov 已提交
1194
#endif
1195

1196
#ifdef CONFIG_MEMCG
1197 1198 1199
	struct mem_cgroup		*memcg_in_oom;
	gfp_t				memcg_oom_gfp_mask;
	int				memcg_oom_order;
1200

1201 1202
	/* Number of pages to reclaim on returning to userland: */
	unsigned int			memcg_nr_pages_over_high;
1203
	unsigned int			wmark_min_throttle_ms;
1204 1205 1206

	/* Used by memcontrol for targeted memcg charge: */
	struct mem_cgroup		*active_memcg;
1207
#endif
1208

1209 1210 1211 1212
#ifdef CONFIG_BLK_CGROUP
	struct request_queue		*throttle_queue;
#endif

1213
#ifdef CONFIG_UPROBES
1214
	struct uprobe_task		*utask;
1215
#endif
K
Kent Overstreet 已提交
1216
#if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1217 1218
	unsigned int			sequential_io;
	unsigned int			sequential_io_avg;
K
Kent Overstreet 已提交
1219
#endif
P
Peter Zijlstra 已提交
1220
#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1221
	unsigned long			task_state_change;
P
Peter Zijlstra 已提交
1222
#endif
1223
	int				pagefault_disabled;
1224
#ifdef CONFIG_MMU
1225
	struct task_struct		*oom_reaper_list;
1226
#endif
1227
#ifdef CONFIG_VMAP_STACK
1228
	struct vm_struct		*stack_vm_area;
1229
#endif
1230
#ifdef CONFIG_THREAD_INFO_IN_TASK
1231 1232
	/* A live task holds one reference: */
	atomic_t			stack_refcount;
1233 1234 1235
#endif
#ifdef CONFIG_LIVEPATCH
	int patch_state;
1236
#endif
1237 1238 1239
#ifdef CONFIG_SECURITY
	/* Used by LSM modules for access restriction: */
	void				*security;
1240
#endif
K
Kees Cook 已提交
1241

1242 1243 1244 1245 1246 1247 1248

	int wait_res_type;
	union {
		struct page	*wait_page;
		struct bio	*wait_bio;
	};
	unsigned long wait_moment;
1249 1250 1251 1252 1253
#ifdef CONFIG_X86_MCE
	u64				mce_addr;
	__u64				mce_ripv : 1,
					mce_whole_page : 1,
					__mce_reserved : 62;
1254

1255 1256
	struct callback_head		mce_kill_me;
#endif
1257 1258 1259 1260 1261 1262 1263 1264 1265
	ALI_HOTFIX_RESERVE(1)
	ALI_HOTFIX_RESERVE(2)
	ALI_HOTFIX_RESERVE(3)
	ALI_HOTFIX_RESERVE(4)
	ALI_HOTFIX_RESERVE(5)
	ALI_HOTFIX_RESERVE(6)
	ALI_HOTFIX_RESERVE(7)
	ALI_HOTFIX_RESERVE(8)

K
Kees Cook 已提交
1266 1267 1268 1269 1270 1271
	/*
	 * New fields for task_struct should be added above here, so that
	 * they are included in the randomized portion of task_struct.
	 */
	randomized_struct_fields_end

1272 1273 1274 1275 1276 1277 1278 1279 1280
	/* CPU-specific state of this task: */
	struct thread_struct		thread;

	/*
	 * WARNING: on x86, 'thread_struct' contains a variable-sized
	 * structure.  It *MUST* be at the end of 'task_struct'.
	 *
	 * Do not put anything below here!
	 */
L
Linus Torvalds 已提交
1281 1282
};

1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304
enum {
	TASK_WAIT_PAGE = 1,
	TASK_WAIT_BIO,
};

static inline void task_set_wait_res(int type, void *res)
{
	if (type == TASK_WAIT_PAGE)
		current->wait_page = (struct page *)res;
	else if (type == TASK_WAIT_BIO)
		current->wait_bio = (struct bio *)res;

	current->wait_res_type = type;
	current->wait_moment = jiffies;
}

static inline void task_clear_wait_res(void)
{
	current->wait_page = NULL;
	current->wait_res_type = 0;
}

A
Alexey Dobriyan 已提交
1305
static inline struct pid *task_pid(struct task_struct *task)
1306
{
1307
	return task->thread_pid;
1308 1309
}

1310 1311 1312 1313 1314
/*
 * the helpers to get the task's different pids as they are seen
 * from various namespaces
 *
 * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
E
Eric W. Biederman 已提交
1315 1316
 * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
 *                     current.
1317 1318 1319 1320
 * task_xid_nr_ns()  : id seen from the ns specified;
 *
 * see also pid_nr() etc in include/linux/pid.h
 */
1321
pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, struct pid_namespace *ns);
1322

A
Alexey Dobriyan 已提交
1323
static inline pid_t task_pid_nr(struct task_struct *tsk)
1324 1325 1326 1327
{
	return tsk->pid;
}

1328
static inline pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1329 1330 1331
{
	return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
}
1332 1333 1334

static inline pid_t task_pid_vnr(struct task_struct *tsk)
{
1335
	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1336 1337 1338
}


A
Alexey Dobriyan 已提交
1339
static inline pid_t task_tgid_nr(struct task_struct *tsk)
1340 1341 1342 1343
{
	return tsk->tgid;
}

1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355
/**
 * pid_alive - check that a task structure is not stale
 * @p: Task structure to be checked.
 *
 * Test if a process is not yet dead (at most zombie state)
 * If pid_alive fails, then pointers within the task structure
 * can be stale and must not be dereferenced.
 *
 * Return: 1 if the process is alive. 0 otherwise.
 */
static inline int pid_alive(const struct task_struct *p)
{
1356
	return p->thread_pid != NULL;
1357
}
1358

1359
static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1360
{
1361
	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1362 1363 1364 1365
}

static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
{
1366
	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1367 1368 1369
}


1370
static inline pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1371
{
1372
	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1373 1374 1375 1376
}

static inline pid_t task_session_vnr(struct task_struct *tsk)
{
1377
	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1378 1379
}

1380 1381
static inline pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
{
E
Eric W. Biederman 已提交
1382
	return __task_pid_nr_ns(tsk, PIDTYPE_TGID, ns);
1383 1384 1385 1386
}

static inline pid_t task_tgid_vnr(struct task_struct *tsk)
{
E
Eric W. Biederman 已提交
1387
	return __task_pid_nr_ns(tsk, PIDTYPE_TGID, NULL);
1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406
}

static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
{
	pid_t pid = 0;

	rcu_read_lock();
	if (pid_alive(tsk))
		pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
	rcu_read_unlock();

	return pid;
}

static inline pid_t task_ppid_nr(const struct task_struct *tsk)
{
	return task_ppid_nr_ns(tsk, &init_pid_ns);
}

1407
/* Obsolete, do not use: */
1408 1409 1410 1411
static inline pid_t task_pgrp_nr(struct task_struct *tsk)
{
	return task_pgrp_nr_ns(tsk, &init_pid_ns);
}
1412

1413 1414 1415
#define TASK_REPORT_IDLE	(TASK_REPORT + 1)
#define TASK_REPORT_MAX		(TASK_REPORT_IDLE << 1)

1416
static inline unsigned int task_state_index(struct task_struct *tsk)
1417
{
1418 1419
	unsigned int tsk_state = READ_ONCE(tsk->state);
	unsigned int state = (tsk_state | tsk->exit_state) & TASK_REPORT;
1420

1421 1422 1423 1424 1425
	BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);

	if (tsk_state == TASK_IDLE)
		state = TASK_REPORT_IDLE;

1426 1427 1428
	return fls(state);
}

1429
static inline char task_index_to_char(unsigned int state)
1430
{
1431
	static const char state_char[] = "RSDTtXZPI";
1432

1433
	BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1);
1434

1435 1436 1437 1438 1439
	return state_char[state];
}

static inline char task_state_to_char(struct task_struct *tsk)
{
1440
	return task_index_to_char(task_state_index(tsk));
1441 1442
}

1443
/**
1444 1445
 * is_global_init - check if a task structure is init. Since init
 * is free to have sub-threads we need to check tgid.
1446 1447 1448
 * @tsk: Task structure to be checked.
 *
 * Check if a task structure is the first user space task the kernel created.
1449 1450
 *
 * Return: 1 if the task structure is init. 0 otherwise.
1451
 */
A
Alexey Dobriyan 已提交
1452
static inline int is_global_init(struct task_struct *tsk)
1453
{
1454
	return task_tgid_nr(tsk) == 1;
1455
}
1456

1457 1458
extern struct pid *cad_pid;

L
Linus Torvalds 已提交
1459 1460 1461
/*
 * Per process flags
 */
1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477
#define PF_IDLE			0x00000002	/* I am an IDLE thread */
#define PF_EXITING		0x00000004	/* Getting shut down */
#define PF_EXITPIDONE		0x00000008	/* PI exit done on shut down */
#define PF_VCPU			0x00000010	/* I'm a virtual CPU */
#define PF_WQ_WORKER		0x00000020	/* I'm a workqueue worker */
#define PF_FORKNOEXEC		0x00000040	/* Forked but didn't exec */
#define PF_MCE_PROCESS		0x00000080      /* Process policy on mce errors */
#define PF_SUPERPRIV		0x00000100	/* Used super-user privileges */
#define PF_DUMPCORE		0x00000200	/* Dumped core */
#define PF_SIGNALED		0x00000400	/* Killed by a signal */
#define PF_MEMALLOC		0x00000800	/* Allocating memory */
#define PF_NPROC_EXCEEDED	0x00001000	/* set_user() noticed that RLIMIT_NPROC was exceeded */
#define PF_USED_MATH		0x00002000	/* If unset the fpu must be initialized before use */
#define PF_USED_ASYNC		0x00004000	/* Used async_schedule*(), used by module init */
#define PF_NOFREEZE		0x00008000	/* This thread should not be frozen */
#define PF_FROZEN		0x00010000	/* Frozen for system suspend */
1478 1479 1480
#define PF_KSWAPD		0x00020000	/* I am kswapd */
#define PF_MEMALLOC_NOFS	0x00040000	/* All allocation requests will inherit GFP_NOFS */
#define PF_MEMALLOC_NOIO	0x00080000	/* All allocation requests will inherit GFP_NOIO */
1481 1482 1483 1484 1485 1486
#define PF_LESS_THROTTLE	0x00100000	/* Throttle me less: I clean memory */
#define PF_KTHREAD		0x00200000	/* I am a kernel thread */
#define PF_RANDOMIZE		0x00400000	/* Randomize virtual address space */
#define PF_SWAPWRITE		0x00800000	/* Allowed to write to swap */
#define PF_NO_SETAFFINITY	0x04000000	/* Userland is not allowed to meddle with cpus_allowed */
#define PF_MCE_EARLY		0x08000000      /* Early kill for mce process policy */
1487
#define PF_IO_WORKER		0x20000000	/* Task is an IO worker */
1488 1489
#define PF_FREEZER_SKIP		0x40000000	/* Freezer should not count it as freezable */
#define PF_SUSPEND_TASK		0x80000000      /* This thread called freeze_processes() and should not be frozen */
L
Linus Torvalds 已提交
1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501

/*
 * Only the _current_ task can read/write to tsk->flags, but other
 * tasks can access tsk->flags in readonly mode for example
 * with tsk_used_math (like during threaded core dumping).
 * There is however an exception to this rule during ptrace
 * or during fork: the ptracer task is allowed to write to the
 * child->flags of its traced child (same goes for fork, the parent
 * can write to the child->flags), because we're guaranteed the
 * child is not running and in turn not changing child->flags
 * at the same time the parent does it.
 */
1502 1503 1504 1505 1506
#define clear_stopped_child_used_math(child)	do { (child)->flags &= ~PF_USED_MATH; } while (0)
#define set_stopped_child_used_math(child)	do { (child)->flags |= PF_USED_MATH; } while (0)
#define clear_used_math()			clear_stopped_child_used_math(current)
#define set_used_math()				set_stopped_child_used_math(current)

L
Linus Torvalds 已提交
1507 1508
#define conditional_stopped_child_used_math(condition, child) \
	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1509 1510 1511

#define conditional_used_math(condition)	conditional_stopped_child_used_math(condition, current)

L
Linus Torvalds 已提交
1512 1513
#define copy_to_stopped_child_used_math(child) \
	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1514

L
Linus Torvalds 已提交
1515
/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1516 1517
#define tsk_used_math(p)			((p)->flags & PF_USED_MATH)
#define used_math()				tsk_used_math(current)
L
Linus Torvalds 已提交
1518

1519 1520 1521 1522 1523 1524 1525 1526 1527 1528
static inline bool is_percpu_thread(void)
{
#ifdef CONFIG_SMP
	return (current->flags & PF_NO_SETAFFINITY) &&
		(current->nr_cpus_allowed  == 1);
#else
	return true;
#endif
}

1529
/* Per-process atomic flags. */
1530 1531 1532
#define PFA_NO_NEW_PRIVS		0	/* May not gain new privileges. */
#define PFA_SPREAD_PAGE			1	/* Spread page cache over cpuset */
#define PFA_SPREAD_SLAB			2	/* Spread some slab caches over cpuset */
1533 1534
#define PFA_SPEC_SSB_DISABLE		3	/* Speculative Store Bypass disabled */
#define PFA_SPEC_SSB_FORCE_DISABLE	4	/* Speculative Store Bypass force disabled*/
1535 1536
#define PFA_SPEC_IB_DISABLE		5	/* Indirect branch speculation restricted */
#define PFA_SPEC_IB_FORCE_DISABLE	6	/* Indirect branch speculation permanently restricted */
1537

1538 1539 1540
#define TASK_PFA_TEST(name, func)					\
	static inline bool task_##func(struct task_struct *p)		\
	{ return test_bit(PFA_##name, &p->atomic_flags); }
1541

1542 1543 1544
#define TASK_PFA_SET(name, func)					\
	static inline void task_set_##func(struct task_struct *p)	\
	{ set_bit(PFA_##name, &p->atomic_flags); }
1545

1546 1547 1548 1549 1550 1551
#define TASK_PFA_CLEAR(name, func)					\
	static inline void task_clear_##func(struct task_struct *p)	\
	{ clear_bit(PFA_##name, &p->atomic_flags); }

TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1552

1553 1554 1555 1556 1557 1558 1559
TASK_PFA_TEST(SPREAD_PAGE, spread_page)
TASK_PFA_SET(SPREAD_PAGE, spread_page)
TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)

TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
TASK_PFA_SET(SPREAD_SLAB, spread_slab)
TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1560

1561 1562 1563 1564 1565 1566 1567
TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable)
TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable)
TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable)

TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)

1568 1569 1570 1571 1572 1573 1574
TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable)
TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable)
TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable)

TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)

1575
static inline void
1576
current_restore_flags(unsigned long orig_flags, unsigned long flags)
1577
{
1578 1579
	current->flags &= ~flags;
	current->flags |= orig_flags & flags;
1580 1581
}

1582 1583
extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
extern int task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
L
Linus Torvalds 已提交
1584
#ifdef CONFIG_SMP
1585 1586
extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask);
extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
L
Linus Torvalds 已提交
1587
#else
1588
static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
1589 1590
{
}
1591
static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
L
Linus Torvalds 已提交
1592
{
1593
	if (!cpumask_test_cpu(0, new_mask))
L
Linus Torvalds 已提交
1594 1595 1596 1597
		return -EINVAL;
	return 0;
}
#endif
1598

1599 1600 1601 1602
#ifndef cpu_relax_yield
#define cpu_relax_yield() cpu_relax()
#endif

1603
extern int yield_to(struct task_struct *p, bool preempt);
1604 1605
extern void set_user_nice(struct task_struct *p, long nice);
extern int task_prio(const struct task_struct *p);
1606

1607 1608 1609 1610 1611 1612 1613 1614 1615 1616
/**
 * task_nice - return the nice value of a given task.
 * @p: the task in question.
 *
 * Return: The nice value [ -20 ... 0 ... 19 ].
 */
static inline int task_nice(const struct task_struct *p)
{
	return PRIO_TO_NICE((p)->static_prio);
}
1617

1618 1619
extern int can_nice(const struct task_struct *p, const int nice);
extern int task_curr(const struct task_struct *p);
L
Linus Torvalds 已提交
1620
extern int idle_cpu(int cpu);
1621
extern int available_idle_cpu(int cpu);
1622 1623 1624
extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
extern int sched_setattr(struct task_struct *, const struct sched_attr *);
1625
extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *);
1626
extern struct task_struct *idle_task(int cpu);
1627

1628 1629
/**
 * is_idle_task - is the specified task an idle task?
1630
 * @p: the task in question.
1631 1632
 *
 * Return: 1 if @p is an idle task. 0 otherwise.
1633
 */
1634
static inline bool is_idle_task(const struct task_struct *p)
1635
{
1636
	return !!(p->flags & PF_IDLE);
1637
}
1638

1639
extern struct task_struct *curr_task(int cpu);
1640
extern void ia64_set_curr_task(int cpu, struct task_struct *p);
L
Linus Torvalds 已提交
1641 1642 1643 1644

void yield(void);

union thread_union {
1645 1646 1647
#ifndef CONFIG_ARCH_TASK_STRUCT_ON_STACK
	struct task_struct task;
#endif
1648
#ifndef CONFIG_THREAD_INFO_IN_TASK
L
Linus Torvalds 已提交
1649
	struct thread_info thread_info;
1650
#endif
L
Linus Torvalds 已提交
1651 1652 1653
	unsigned long stack[THREAD_SIZE/sizeof(long)];
};

1654 1655 1656 1657 1658 1659
#ifndef CONFIG_THREAD_INFO_IN_TASK
extern struct thread_info init_thread_info;
#endif

extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];

1660 1661 1662 1663 1664 1665 1666 1667 1668
#ifdef CONFIG_THREAD_INFO_IN_TASK
static inline struct thread_info *task_thread_info(struct task_struct *task)
{
	return &task->thread_info;
}
#elif !defined(__HAVE_THREAD_FUNCTIONS)
# define task_thread_info(task)	((struct thread_info *)(task)->stack)
#endif

1669 1670 1671 1672 1673
/*
 * find a task by one of its numerical ids
 *
 * find_task_by_pid_ns():
 *      finds a task by its pid in the specified namespace
1674 1675
 * find_task_by_vpid():
 *      finds a task by its virtual pid
1676
 *
1677
 * see also find_vpid() etc in include/linux/pid.h
1678 1679
 */

1680
extern struct task_struct *find_task_by_vpid(pid_t nr);
1681
extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns);
1682

1683 1684 1685 1686 1687
/*
 * find a task by its virtual pid and get the task struct
 */
extern struct task_struct *find_get_task_by_vpid(pid_t nr);

1688 1689
extern int wake_up_state(struct task_struct *tsk, unsigned int state);
extern int wake_up_process(struct task_struct *tsk);
1690
extern void wake_up_new_task(struct task_struct *tsk);
1691

L
Linus Torvalds 已提交
1692
#ifdef CONFIG_SMP
1693
extern void kick_process(struct task_struct *tsk);
L
Linus Torvalds 已提交
1694
#else
1695
static inline void kick_process(struct task_struct *tsk) { }
L
Linus Torvalds 已提交
1696 1697
#endif

1698
extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
1699

1700 1701 1702 1703
static inline void set_task_comm(struct task_struct *tsk, const char *from)
{
	__set_task_comm(tsk, from, false);
}
1704

1705 1706 1707 1708 1709
extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk);
#define get_task_comm(buf, tsk) ({			\
	BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN);	\
	__get_task_comm(buf, sizeof(buf), tsk);		\
})
L
Linus Torvalds 已提交
1710 1711

#ifdef CONFIG_SMP
1712
void scheduler_ipi(void);
R
Roland McGrath 已提交
1713
extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
L
Linus Torvalds 已提交
1714
#else
1715
static inline void scheduler_ipi(void) { }
1716
static inline unsigned long wait_task_inactive(struct task_struct *p, long match_state)
R
Roland McGrath 已提交
1717 1718 1719
{
	return 1;
}
L
Linus Torvalds 已提交
1720 1721
#endif

1722 1723 1724
/*
 * Set thread flags in other task's structures.
 * See asm/thread_info.h for TIF_xxxx flags available:
L
Linus Torvalds 已提交
1725 1726 1727
 */
static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
{
A
Al Viro 已提交
1728
	set_ti_thread_flag(task_thread_info(tsk), flag);
L
Linus Torvalds 已提交
1729 1730 1731 1732
}

static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
{
A
Al Viro 已提交
1733
	clear_ti_thread_flag(task_thread_info(tsk), flag);
L
Linus Torvalds 已提交
1734 1735
}

1736 1737 1738 1739 1740 1741
static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag,
					  bool value)
{
	update_ti_thread_flag(task_thread_info(tsk), flag, value);
}

L
Linus Torvalds 已提交
1742 1743
static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
{
A
Al Viro 已提交
1744
	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
L
Linus Torvalds 已提交
1745 1746 1747 1748
}

static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
{
A
Al Viro 已提交
1749
	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
L
Linus Torvalds 已提交
1750 1751 1752 1753
}

static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
{
A
Al Viro 已提交
1754
	return test_ti_thread_flag(task_thread_info(tsk), flag);
L
Linus Torvalds 已提交
1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766
}

static inline void set_tsk_need_resched(struct task_struct *tsk)
{
	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
}

static inline void clear_tsk_need_resched(struct task_struct *tsk)
{
	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
}

1767 1768 1769 1770 1771
static inline int test_tsk_need_resched(struct task_struct *tsk)
{
	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
}

L
Linus Torvalds 已提交
1772 1773 1774 1775 1776 1777
/*
 * cond_resched() and cond_resched_lock(): latency reduction via
 * explicit rescheduling in places that are safe. The return
 * value indicates whether a reschedule was done in fact.
 * cond_resched_lock() will drop the spinlock before scheduling,
 */
1778
#ifndef CONFIG_PREEMPT
1779
extern int _cond_resched(void);
1780 1781 1782
#else
static inline int _cond_resched(void) { return 0; }
#endif
1783

1784
#define cond_resched() ({			\
1785
	___might_sleep(__FILE__, __LINE__, 0);	\
1786 1787
	_cond_resched();			\
})
1788

1789 1790 1791
extern int __cond_resched_lock(spinlock_t *lock);

#define cond_resched_lock(lock) ({				\
1792
	___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
1793 1794 1795
	__cond_resched_lock(lock);				\
})

1796 1797 1798 1799 1800 1801 1802 1803 1804
static inline void cond_resched_rcu(void)
{
#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
	rcu_read_unlock();
	cond_resched();
	rcu_read_lock();
#endif
}

L
Linus Torvalds 已提交
1805 1806
/*
 * Does a critical section need to be broken due to another
N
Nick Piggin 已提交
1807 1808
 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
 * but a general need for low latency)
L
Linus Torvalds 已提交
1809
 */
N
Nick Piggin 已提交
1810
static inline int spin_needbreak(spinlock_t *lock)
L
Linus Torvalds 已提交
1811
{
N
Nick Piggin 已提交
1812 1813 1814
#ifdef CONFIG_PREEMPT
	return spin_is_contended(lock);
#else
L
Linus Torvalds 已提交
1815
	return 0;
N
Nick Piggin 已提交
1816
#endif
L
Linus Torvalds 已提交
1817 1818
}

1819 1820 1821 1822 1823
static __always_inline bool need_resched(void)
{
	return unlikely(tif_need_resched());
}

L
Linus Torvalds 已提交
1824 1825 1826 1827 1828 1829 1830
/*
 * Wrappers for p->thread_info->cpu access. No-op on UP.
 */
#ifdef CONFIG_SMP

static inline unsigned int task_cpu(const struct task_struct *p)
{
1831
#ifdef CONFIG_THREAD_INFO_IN_TASK
1832
	return READ_ONCE(p->cpu);
1833
#else
1834
	return READ_ONCE(task_thread_info(p)->cpu);
1835
#endif
L
Linus Torvalds 已提交
1836 1837
}

I
Ingo Molnar 已提交
1838
extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
L
Linus Torvalds 已提交
1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852

#else

static inline unsigned int task_cpu(const struct task_struct *p)
{
	return 0;
}

static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
{
}

#endif /* CONFIG_SMP */

1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864
/*
 * In order to reduce various lock holder preemption latencies provide an
 * interface to see if a vCPU is currently running or not.
 *
 * This allows us to terminate optimistic spin loops and block, analogous to
 * the native optimistic spin heuristic of testing if the lock owner task is
 * running or not.
 */
#ifndef vcpu_is_preempted
# define vcpu_is_preempted(cpu)	false
#endif

1865 1866
extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
1867

D
Dave Hansen 已提交
1868 1869 1870 1871
#ifndef TASK_SIZE_OF
#define TASK_SIZE_OF(tsk)	TASK_SIZE
#endif

1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895
#ifdef CONFIG_RSEQ

/*
 * Map the event mask on the user-space ABI enum rseq_cs_flags
 * for direct mask checks.
 */
enum rseq_event_mask_bits {
	RSEQ_EVENT_PREEMPT_BIT	= RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT,
	RSEQ_EVENT_SIGNAL_BIT	= RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT,
	RSEQ_EVENT_MIGRATE_BIT	= RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT,
};

enum rseq_event_mask {
	RSEQ_EVENT_PREEMPT	= (1U << RSEQ_EVENT_PREEMPT_BIT),
	RSEQ_EVENT_SIGNAL	= (1U << RSEQ_EVENT_SIGNAL_BIT),
	RSEQ_EVENT_MIGRATE	= (1U << RSEQ_EVENT_MIGRATE_BIT),
};

static inline void rseq_set_notify_resume(struct task_struct *t)
{
	if (t->rseq)
		set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
}

1896
void __rseq_handle_notify_resume(struct ksignal *sig, struct pt_regs *regs);
1897

1898 1899
static inline void rseq_handle_notify_resume(struct ksignal *ksig,
					     struct pt_regs *regs)
1900 1901
{
	if (current->rseq)
1902
		__rseq_handle_notify_resume(ksig, regs);
1903 1904
}

1905 1906
static inline void rseq_signal_deliver(struct ksignal *ksig,
				       struct pt_regs *regs)
1907 1908 1909 1910
{
	preempt_disable();
	__set_bit(RSEQ_EVENT_SIGNAL_BIT, &current->rseq_event_mask);
	preempt_enable();
1911
	rseq_handle_notify_resume(ksig, regs);
1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929
}

/* rseq_preempt() requires preemption to be disabled. */
static inline void rseq_preempt(struct task_struct *t)
{
	__set_bit(RSEQ_EVENT_PREEMPT_BIT, &t->rseq_event_mask);
	rseq_set_notify_resume(t);
}

/* rseq_migrate() requires preemption to be disabled. */
static inline void rseq_migrate(struct task_struct *t)
{
	__set_bit(RSEQ_EVENT_MIGRATE_BIT, &t->rseq_event_mask);
	rseq_set_notify_resume(t);
}

/*
 * If parent process has a registered restartable sequences area, the
1930
 * child inherits. Only applies when forking a process, not a thread.
1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959
 */
static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
{
	if (clone_flags & CLONE_THREAD) {
		t->rseq = NULL;
		t->rseq_len = 0;
		t->rseq_sig = 0;
		t->rseq_event_mask = 0;
	} else {
		t->rseq = current->rseq;
		t->rseq_len = current->rseq_len;
		t->rseq_sig = current->rseq_sig;
		t->rseq_event_mask = current->rseq_event_mask;
	}
}

static inline void rseq_execve(struct task_struct *t)
{
	t->rseq = NULL;
	t->rseq_len = 0;
	t->rseq_sig = 0;
	t->rseq_event_mask = 0;
}

#else

static inline void rseq_set_notify_resume(struct task_struct *t)
{
}
1960 1961
static inline void rseq_handle_notify_resume(struct ksignal *ksig,
					     struct pt_regs *regs)
1962 1963
{
}
1964 1965
static inline void rseq_signal_deliver(struct ksignal *ksig,
				       struct pt_regs *regs)
1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994
{
}
static inline void rseq_preempt(struct task_struct *t)
{
}
static inline void rseq_migrate(struct task_struct *t)
{
}
static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
{
}
static inline void rseq_execve(struct task_struct *t)
{
}

#endif

#ifdef CONFIG_DEBUG_RSEQ

void rseq_syscall(struct pt_regs *regs);

#else

static inline void rseq_syscall(struct pt_regs *regs)
{
}

#endif

1995 1996 1997 1998 1999
struct cpuacct_usage_result {
	u64 user, nice, system, irq, softirq;
	u64 steal, iowait, idle, guest, guest_nice;
};

L
Linus Torvalds 已提交
2000
#endif