sched.h 88.3 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3
#ifndef _LINUX_SCHED_H
#define _LINUX_SCHED_H

4
#include <uapi/linux/sched.h>
5

6 7
#include <linux/sched/prio.h>

8 9 10 11 12

struct sched_param {
	int sched_priority;
};

L
Linus Torvalds 已提交
13 14 15 16 17 18 19 20
#include <asm/param.h>	/* for HZ */

#include <linux/capability.h>
#include <linux/threads.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/timex.h>
#include <linux/jiffies.h>
21
#include <linux/plist.h>
L
Linus Torvalds 已提交
22 23 24 25 26
#include <linux/rbtree.h>
#include <linux/thread_info.h>
#include <linux/cpumask.h>
#include <linux/errno.h>
#include <linux/nodemask.h>
27
#include <linux/mm_types.h>
28
#include <linux/preempt_mask.h>
L
Linus Torvalds 已提交
29 30 31

#include <asm/page.h>
#include <asm/ptrace.h>
32
#include <linux/cputime.h>
L
Linus Torvalds 已提交
33 34 35

#include <linux/smp.h>
#include <linux/sem.h>
36
#include <linux/shm.h>
L
Linus Torvalds 已提交
37 38 39 40 41 42
#include <linux/signal.h>
#include <linux/compiler.h>
#include <linux/completion.h>
#include <linux/pid.h>
#include <linux/percpu.h>
#include <linux/topology.h>
P
Peter Zijlstra 已提交
43
#include <linux/proportions.h>
L
Linus Torvalds 已提交
44
#include <linux/seccomp.h>
I
Ingo Molnar 已提交
45
#include <linux/rcupdate.h>
46
#include <linux/rculist.h>
I
Ingo Molnar 已提交
47
#include <linux/rtmutex.h>
L
Linus Torvalds 已提交
48

49 50 51 52 53
#include <linux/time.h>
#include <linux/param.h>
#include <linux/resource.h>
#include <linux/timer.h>
#include <linux/hrtimer.h>
54
#include <linux/task_io_accounting.h>
A
Arjan van de Ven 已提交
55
#include <linux/latencytop.h>
56
#include <linux/cred.h>
P
Peter Zijlstra 已提交
57
#include <linux/llist.h>
58
#include <linux/uidgid.h>
59
#include <linux/gfp.h>
60
#include <linux/magic.h>
61 62

#include <asm/processor.h>
H
H. J. Lu 已提交
63

64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104
#define SCHED_ATTR_SIZE_VER0	48	/* sizeof first published struct */

/*
 * Extended scheduling parameters data structure.
 *
 * This is needed because the original struct sched_param can not be
 * altered without introducing ABI issues with legacy applications
 * (e.g., in sched_getparam()).
 *
 * However, the possibility of specifying more than just a priority for
 * the tasks may be useful for a wide variety of application fields, e.g.,
 * multimedia, streaming, automation and control, and many others.
 *
 * This variant (sched_attr) is meant at describing a so-called
 * sporadic time-constrained task. In such model a task is specified by:
 *  - the activation period or minimum instance inter-arrival time;
 *  - the maximum (or average, depending on the actual scheduling
 *    discipline) computation time of all instances, a.k.a. runtime;
 *  - the deadline (relative to the actual activation time) of each
 *    instance.
 * Very briefly, a periodic (sporadic) task asks for the execution of
 * some specific computation --which is typically called an instance--
 * (at most) every period. Moreover, each instance typically lasts no more
 * than the runtime and must be completed by time instant t equal to
 * the instance activation time + the deadline.
 *
 * This is reflected by the actual fields of the sched_attr structure:
 *
 *  @size		size of the structure, for fwd/bwd compat.
 *
 *  @sched_policy	task's scheduling policy
 *  @sched_flags	for customizing the scheduler behaviour
 *  @sched_nice		task's nice value      (SCHED_NORMAL/BATCH)
 *  @sched_priority	task's static priority (SCHED_FIFO/RR)
 *  @sched_deadline	representative of the task's deadline
 *  @sched_runtime	representative of the task's runtime
 *  @sched_period	representative of the task's period
 *
 * Given this task model, there are a multiplicity of scheduling algorithms
 * and policies, that can be used to ensure all the tasks will make their
 * timing constraints.
105 106 107 108
 *
 * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the
 * only user of this new interface. More information about the algorithm
 * available in the scheduling class file or in Documentation/.
109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127
 */
struct sched_attr {
	u32 size;

	u32 sched_policy;
	u64 sched_flags;

	/* SCHED_NORMAL, SCHED_BATCH */
	s32 sched_nice;

	/* SCHED_FIFO, SCHED_RR */
	u32 sched_priority;

	/* SCHED_DEADLINE */
	u64 sched_runtime;
	u64 sched_deadline;
	u64 sched_period;
};

128
struct futex_pi_state;
129
struct robust_list_head;
130
struct bio_list;
131
struct fs_struct;
132
struct perf_event_context;
133
struct blk_plug;
134
struct filename;
L
Linus Torvalds 已提交
135

D
Davidlohr Bueso 已提交
136 137 138 139
#define VMACACHE_BITS 2
#define VMACACHE_SIZE (1U << VMACACHE_BITS)
#define VMACACHE_MASK (VMACACHE_SIZE - 1)

L
Linus Torvalds 已提交
140 141 142 143 144 145 146 147 148 149 150
/*
 * These are the constant used to fake the fixed-point load-average
 * counting. Some notes:
 *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
 *    a load-average precision of 10 bits integer + 11 bits fractional
 *  - if you want to count load-averages more often, you need more
 *    precision, or rounding will get you. With 2-second counting freq,
 *    the EXP_n values would be 1981, 2034 and 2043 if still using only
 *    11 bit fractions.
 */
extern unsigned long avenrun[];		/* Load averages */
151
extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
L
Linus Torvalds 已提交
152 153 154

#define FSHIFT		11		/* nr of bits of precision */
#define FIXED_1		(1<<FSHIFT)	/* 1.0 as fixed-point */
155
#define LOAD_FREQ	(5*HZ+1)	/* 5 sec intervals */
L
Linus Torvalds 已提交
156 157 158 159 160 161 162 163 164 165 166 167 168 169
#define EXP_1		1884		/* 1/exp(5sec/1min) as fixed-point */
#define EXP_5		2014		/* 1/exp(5sec/5min) */
#define EXP_15		2037		/* 1/exp(5sec/15min) */

#define CALC_LOAD(load,exp,n) \
	load *= exp; \
	load += n*(FIXED_1-exp); \
	load >>= FSHIFT;

extern unsigned long total_forks;
extern int nr_threads;
DECLARE_PER_CPU(unsigned long, process_counts);
extern int nr_processes(void);
extern unsigned long nr_running(void);
170
extern bool single_task_running(void);
L
Linus Torvalds 已提交
171
extern unsigned long nr_iowait(void);
172
extern unsigned long nr_iowait_cpu(int cpu);
173
extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load);
174

175
extern void calc_global_load(unsigned long ticks);
176
extern void update_cpu_load_nohz(void);
L
Linus Torvalds 已提交
177

178 179
extern unsigned long get_parent_ip(unsigned long addr);

180 181
extern void dump_cpu_task(int cpu);

I
Ingo Molnar 已提交
182 183
struct seq_file;
struct cfs_rq;
184
struct task_group;
I
Ingo Molnar 已提交
185 186 187 188
#ifdef CONFIG_SCHED_DEBUG
extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
extern void proc_sched_set_task(struct task_struct *p);
extern void
189
print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
I
Ingo Molnar 已提交
190
#endif
L
Linus Torvalds 已提交
191

192 193 194 195 196 197 198 199 200 201
/*
 * 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.
 */
L
Linus Torvalds 已提交
202 203 204
#define TASK_RUNNING		0
#define TASK_INTERRUPTIBLE	1
#define TASK_UNINTERRUPTIBLE	2
M
Matthew Wilcox 已提交
205 206
#define __TASK_STOPPED		4
#define __TASK_TRACED		8
207
/* in tsk->exit_state */
208 209
#define EXIT_DEAD		16
#define EXIT_ZOMBIE		32
210
#define EXIT_TRACE		(EXIT_ZOMBIE | EXIT_DEAD)
211
/* in tsk->state again */
212
#define TASK_DEAD		64
M
Matthew Wilcox 已提交
213
#define TASK_WAKEKILL		128
P
Peter Zijlstra 已提交
214
#define TASK_WAKING		256
215 216
#define TASK_PARKED		512
#define TASK_STATE_MAX		1024
M
Matthew Wilcox 已提交
217

218
#define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWP"
219

220 221
extern char ___assert_task_state[1 - 2*!!(
		sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
M
Matthew Wilcox 已提交
222 223 224 225 226

/* Convenience macros for the sake of set_task_state */
#define TASK_KILLABLE		(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
#define TASK_STOPPED		(TASK_WAKEKILL | __TASK_STOPPED)
#define TASK_TRACED		(TASK_WAKEKILL | __TASK_TRACED)
L
Linus Torvalds 已提交
227

228 229
/* Convenience macros for the sake of wake_up */
#define TASK_NORMAL		(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
M
Matthew Wilcox 已提交
230
#define TASK_ALL		(TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
231 232 233

/* get_task_state() */
#define TASK_REPORT		(TASK_RUNNING | TASK_INTERRUPTIBLE | \
M
Matthew Wilcox 已提交
234
				 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
235
				 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD)
236

M
Matthew Wilcox 已提交
237 238
#define task_is_traced(task)	((task->state & __TASK_TRACED) != 0)
#define task_is_stopped(task)	((task->state & __TASK_STOPPED) != 0)
239
#define task_is_stopped_or_traced(task)	\
M
Matthew Wilcox 已提交
240
			((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
241
#define task_contributes_to_load(task)	\
242
				((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
T
Tejun Heo 已提交
243
				 (task->flags & PF_FROZEN) == 0)
L
Linus Torvalds 已提交
244

P
Peter Zijlstra 已提交
245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281
#ifdef CONFIG_DEBUG_ATOMIC_SLEEP

#define __set_task_state(tsk, state_value)			\
	do {							\
		(tsk)->task_state_change = _THIS_IP_;		\
		(tsk)->state = (state_value);			\
	} while (0)
#define set_task_state(tsk, state_value)			\
	do {							\
		(tsk)->task_state_change = _THIS_IP_;		\
		set_mb((tsk)->state, (state_value));		\
	} while (0)

/*
 * 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:
 *
 *	set_current_state(TASK_UNINTERRUPTIBLE);
 *	if (do_i_need_to_sleep())
 *		schedule();
 *
 * If the caller does not need such serialisation then use __set_current_state()
 */
#define __set_current_state(state_value)			\
	do {							\
		current->task_state_change = _THIS_IP_;		\
		current->state = (state_value);			\
	} while (0)
#define set_current_state(state_value)				\
	do {							\
		current->task_state_change = _THIS_IP_;		\
		set_mb(current->state, (state_value));		\
	} while (0)

#else

L
Linus Torvalds 已提交
282 283 284 285 286
#define __set_task_state(tsk, state_value)		\
	do { (tsk)->state = (state_value); } while (0)
#define set_task_state(tsk, state_value)		\
	set_mb((tsk)->state, (state_value))

287 288 289 290 291 292 293 294 295 296 297
/*
 * 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:
 *
 *	set_current_state(TASK_UNINTERRUPTIBLE);
 *	if (do_i_need_to_sleep())
 *		schedule();
 *
 * If the caller does not need such serialisation then use __set_current_state()
 */
P
Peter Zijlstra 已提交
298
#define __set_current_state(state_value)		\
L
Linus Torvalds 已提交
299
	do { current->state = (state_value); } while (0)
P
Peter Zijlstra 已提交
300
#define set_current_state(state_value)			\
L
Linus Torvalds 已提交
301 302
	set_mb(current->state, (state_value))

P
Peter Zijlstra 已提交
303 304
#endif

L
Linus Torvalds 已提交
305 306 307 308 309 310 311 312 313 314 315 316 317 318
/* Task command name length */
#define TASK_COMM_LEN 16

#include <linux/spinlock.h>

/*
 * This serializes "schedule()" and also protects
 * the run-queue from deletions/modifications (but
 * _adding_ to the beginning of the run-queue has
 * a separate lock).
 */
extern rwlock_t tasklist_lock;
extern spinlock_t mmlist_lock;

319
struct task_struct;
L
Linus Torvalds 已提交
320

321 322 323 324
#ifdef CONFIG_PROVE_RCU
extern int lockdep_tasklist_lock_is_held(void);
#endif /* #ifdef CONFIG_PROVE_RCU */

L
Linus Torvalds 已提交
325 326
extern void sched_init(void);
extern void sched_init_smp(void);
327
extern asmlinkage void schedule_tail(struct task_struct *prev);
328
extern void init_idle(struct task_struct *idle, int cpu);
I
Ingo Molnar 已提交
329
extern void init_idle_bootup_task(struct task_struct *idle);
L
Linus Torvalds 已提交
330

331 332
extern cpumask_var_t cpu_isolated_map;

333
extern int runqueue_is_locked(int cpu);
I
Ingo Molnar 已提交
334

335
#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
336
extern void nohz_balance_enter_idle(int cpu);
337
extern void set_cpu_sd_state_idle(void);
338
extern int get_nohz_timer_target(int pinned);
339
#else
340
static inline void nohz_balance_enter_idle(int cpu) { }
341
static inline void set_cpu_sd_state_idle(void) { }
342 343 344 345
static inline int get_nohz_timer_target(int pinned)
{
	return smp_processor_id();
}
346
#endif
L
Linus Torvalds 已提交
347

I
Ingo Molnar 已提交
348
/*
I
Ingo Molnar 已提交
349
 * Only dump TASK_* tasks. (0 for all tasks)
I
Ingo Molnar 已提交
350 351 352 353 354
 */
extern void show_state_filter(unsigned long state_filter);

static inline void show_state(void)
{
I
Ingo Molnar 已提交
355
	show_state_filter(0);
I
Ingo Molnar 已提交
356 357
}

L
Linus Torvalds 已提交
358 359 360 361 362 363 364 365 366 367 368 369 370 371
extern void show_regs(struct pt_regs *);

/*
 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
 * task), SP is the stack pointer of the first frame that should be shown in the back
 * trace (or NULL if the entire call-chain of the task should be shown).
 */
extern void show_stack(struct task_struct *task, unsigned long *sp);

extern void cpu_init (void);
extern void trap_init(void);
extern void update_process_times(int user);
extern void scheduler_tick(void);

372 373
extern void sched_show_task(struct task_struct *p);

374
#ifdef CONFIG_LOCKUP_DETECTOR
I
Ingo Molnar 已提交
375
extern void touch_softlockup_watchdog(void);
376
extern void touch_softlockup_watchdog_sync(void);
377
extern void touch_all_softlockup_watchdogs(void);
378 379 380
extern int proc_dowatchdog_thresh(struct ctl_table *table, int write,
				  void __user *buffer,
				  size_t *lenp, loff_t *ppos);
I
Ingo Molnar 已提交
381
extern unsigned int  softlockup_panic;
382
void lockup_detector_init(void);
I
Ingo Molnar 已提交
383 384 385 386
#else
static inline void touch_softlockup_watchdog(void)
{
}
387 388 389
static inline void touch_softlockup_watchdog_sync(void)
{
}
390 391 392
static inline void touch_all_softlockup_watchdogs(void)
{
}
393 394 395
static inline void lockup_detector_init(void)
{
}
I
Ingo Molnar 已提交
396 397
#endif

398 399 400 401 402 403 404 405
#ifdef CONFIG_DETECT_HUNG_TASK
void reset_hung_task_detector(void);
#else
static inline void reset_hung_task_detector(void)
{
}
#endif

L
Linus Torvalds 已提交
406 407
/* Attach to any functions which should be ignored in wchan output. */
#define __sched		__attribute__((__section__(".sched.text")))
408 409 410 411

/* Linker adds these: start and end of __sched functions */
extern char __sched_text_start[], __sched_text_end[];

L
Linus Torvalds 已提交
412 413 414 415
/* Is this address in the __sched functions? */
extern int in_sched_functions(unsigned long addr);

#define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
416
extern signed long schedule_timeout(signed long timeout);
417
extern signed long schedule_timeout_interruptible(signed long timeout);
M
Matthew Wilcox 已提交
418
extern signed long schedule_timeout_killable(signed long timeout);
419
extern signed long schedule_timeout_uninterruptible(signed long timeout);
L
Linus Torvalds 已提交
420
asmlinkage void schedule(void);
421
extern void schedule_preempt_disabled(void);
L
Linus Torvalds 已提交
422

423 424 425 426 427 428 429
extern long io_schedule_timeout(long timeout);

static inline void io_schedule(void)
{
	io_schedule_timeout(MAX_SCHEDULE_TIMEOUT);
}

S
Serge E. Hallyn 已提交
430
struct nsproxy;
431
struct user_namespace;
L
Linus Torvalds 已提交
432

433 434
#ifdef CONFIG_MMU
extern void arch_pick_mmap_layout(struct mm_struct *mm);
L
Linus Torvalds 已提交
435 436 437 438 439 440 441
extern unsigned long
arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
		       unsigned long, unsigned long);
extern unsigned long
arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
			  unsigned long len, unsigned long pgoff,
			  unsigned long flags);
442 443 444
#else
static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
#endif
L
Linus Torvalds 已提交
445

446 447 448 449
#define SUID_DUMP_DISABLE	0	/* No setuid dumping */
#define SUID_DUMP_USER		1	/* Dump as user of process */
#define SUID_DUMP_ROOT		2	/* Dump as root */

450
/* mm flags */
H
Hugh Dickins 已提交
451

452
/* for SUID_DUMP_* above */
453
#define MMF_DUMPABLE_BITS 2
H
Hugh Dickins 已提交
454
#define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
455

456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472
extern void set_dumpable(struct mm_struct *mm, int value);
/*
 * This returns the actual value of the suid_dumpable flag. For things
 * that are using this for checking for privilege transitions, it must
 * test against SUID_DUMP_USER rather than treating it as a boolean
 * value.
 */
static inline int __get_dumpable(unsigned long mm_flags)
{
	return mm_flags & MMF_DUMPABLE_MASK;
}

static inline int get_dumpable(struct mm_struct *mm)
{
	return __get_dumpable(mm->flags);
}

473 474 475 476 477
/* coredump filter bits */
#define MMF_DUMP_ANON_PRIVATE	2
#define MMF_DUMP_ANON_SHARED	3
#define MMF_DUMP_MAPPED_PRIVATE	4
#define MMF_DUMP_MAPPED_SHARED	5
R
Roland McGrath 已提交
478
#define MMF_DUMP_ELF_HEADERS	6
479 480
#define MMF_DUMP_HUGETLB_PRIVATE 7
#define MMF_DUMP_HUGETLB_SHARED  8
H
Hugh Dickins 已提交
481

482
#define MMF_DUMP_FILTER_SHIFT	MMF_DUMPABLE_BITS
483
#define MMF_DUMP_FILTER_BITS	7
484 485 486
#define MMF_DUMP_FILTER_MASK \
	(((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
#define MMF_DUMP_FILTER_DEFAULT \
487
	((1 << MMF_DUMP_ANON_PRIVATE) |	(1 << MMF_DUMP_ANON_SHARED) |\
488 489 490 491 492 493 494
	 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)

#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
# define MMF_DUMP_MASK_DEFAULT_ELF	(1 << MMF_DUMP_ELF_HEADERS)
#else
# define MMF_DUMP_MASK_DEFAULT_ELF	0
#endif
H
Hugh Dickins 已提交
495 496
					/* leave room for more dump flags */
#define MMF_VM_MERGEABLE	16	/* KSM may merge identical pages */
A
Andrea Arcangeli 已提交
497
#define MMF_VM_HUGEPAGE		17	/* set when VM_HUGEPAGE is set on vma */
498
#define MMF_EXE_FILE_CHANGED	18	/* see prctl_set_mm_exe_file() */
H
Hugh Dickins 已提交
499

500 501
#define MMF_HAS_UPROBES		19	/* has uprobes */
#define MMF_RECALC_UPROBES	20	/* MMF_HAS_UPROBES can be wrong */
502

H
Hugh Dickins 已提交
503
#define MMF_INIT_MASK		(MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
504

L
Linus Torvalds 已提交
505 506 507 508
struct sighand_struct {
	atomic_t		count;
	struct k_sigaction	action[_NSIG];
	spinlock_t		siglock;
D
Davide Libenzi 已提交
509
	wait_queue_head_t	signalfd_wqh;
L
Linus Torvalds 已提交
510 511
};

512
struct pacct_struct {
513 514
	int			ac_flag;
	long			ac_exitcode;
515
	unsigned long		ac_mem;
516 517
	cputime_t		ac_utime, ac_stime;
	unsigned long		ac_minflt, ac_majflt;
518 519
};

520 521 522
struct cpu_itimer {
	cputime_t expires;
	cputime_t incr;
523 524
	u32 error;
	u32 incr_error;
525 526
};

527 528 529 530 531 532 533 534 535 536 537 538
/**
 * struct cputime - snaphsot of system and user cputime
 * @utime: time spent in user mode
 * @stime: time spent in system mode
 *
 * Gathers a generic snapshot of user and system time.
 */
struct cputime {
	cputime_t utime;
	cputime_t stime;
};

539 540 541 542 543
/**
 * struct task_cputime - collected CPU time counts
 * @utime:		time spent in user mode, in &cputime_t units
 * @stime:		time spent in kernel mode, in &cputime_t units
 * @sum_exec_runtime:	total time spent on the CPU, in nanoseconds
544
 *
545 546 547 548 549
 * This is an extension of struct cputime that includes the total runtime
 * spent by the task from the scheduler point of view.
 *
 * As a result, this structure groups together three kinds of CPU time
 * that are tracked for threads and thread groups.  Most things considering
550 551 552 553 554 555 556 557 558 559 560 561 562
 * CPU time want to group these counts together and treat all three
 * of them in parallel.
 */
struct task_cputime {
	cputime_t utime;
	cputime_t stime;
	unsigned long long sum_exec_runtime;
};
/* Alternate field names when used to cache expirations. */
#define prof_exp	stime
#define virt_exp	utime
#define sched_exp	sum_exec_runtime

563 564
#define INIT_CPUTIME	\
	(struct task_cputime) {					\
565 566
		.utime = 0,					\
		.stime = 0,					\
567 568 569
		.sum_exec_runtime = 0,				\
	}

570 571 572 573 574 575
#ifdef CONFIG_PREEMPT_COUNT
#define PREEMPT_DISABLED	(1 + PREEMPT_ENABLED)
#else
#define PREEMPT_DISABLED	PREEMPT_ENABLED
#endif

P
Peter Zijlstra 已提交
576 577 578
/*
 * Disable preemption until the scheduler is running.
 * Reset by start_kernel()->sched_init()->init_idle().
P
Peter Zijlstra 已提交
579 580 581
 *
 * We include PREEMPT_ACTIVE to avoid cond_resched() from working
 * before the scheduler is active -- see should_resched().
P
Peter Zijlstra 已提交
582
 */
583
#define INIT_PREEMPT_COUNT	(PREEMPT_DISABLED + PREEMPT_ACTIVE)
P
Peter Zijlstra 已提交
584

585
/**
586 587 588 589 590
 * struct thread_group_cputimer - thread group interval timer counts
 * @cputime:		thread group interval timers.
 * @running:		non-zero when there are timers running and
 * 			@cputime receives updates.
 * @lock:		lock for fields in this struct.
591 592
 *
 * This structure contains the version of task_cputime, above, that is
593
 * used for thread group CPU timer calculations.
594
 */
595 596 597
struct thread_group_cputimer {
	struct task_cputime cputime;
	int running;
598
	raw_spinlock_t lock;
599 600
};

601
#include <linux/rwsem.h>
602 603
struct autogroup;

L
Linus Torvalds 已提交
604
/*
605
 * NOTE! "signal_struct" does not have its own
L
Linus Torvalds 已提交
606 607 608 609 610 611
 * locking, because a shared signal_struct always
 * implies a shared sighand_struct, so locking
 * sighand_struct is always a proper superset of
 * the locking of signal_struct.
 */
struct signal_struct {
612
	atomic_t		sigcnt;
L
Linus Torvalds 已提交
613
	atomic_t		live;
614
	int			nr_threads;
615
	struct list_head	thread_head;
L
Linus Torvalds 已提交
616 617 618 619

	wait_queue_head_t	wait_chldexit;	/* for wait4() */

	/* current thread group signal load-balancing target: */
620
	struct task_struct	*curr_target;
L
Linus Torvalds 已提交
621 622 623 624 625 626 627 628 629 630 631 632

	/* shared signal handling: */
	struct sigpending	shared_pending;

	/* thread group exit support */
	int			group_exit_code;
	/* overloaded:
	 * - notify group_exit_task when ->count is equal to notify_count
	 * - everyone except group_exit_task is stopped during signal delivery
	 *   of fatal signals, group_exit_task processes the signal.
	 */
	int			notify_count;
633
	struct task_struct	*group_exit_task;
L
Linus Torvalds 已提交
634 635 636 637 638

	/* thread group stop support, overloads group_exit_code too */
	int			group_stop_count;
	unsigned int		flags; /* see SIGNAL_* flags below */

639 640 641 642 643 644 645 646 647 648 649 650
	/*
	 * PR_SET_CHILD_SUBREAPER marks a process, like a service
	 * manager, to re-parent orphan (double-forking) child processes
	 * to this process instead of 'init'. The service manager is
	 * able to receive SIGCHLD signals and is able to investigate
	 * the process until it calls wait(). All children of this
	 * process will inherit a flag if they should look for a
	 * child_subreaper process at exit.
	 */
	unsigned int		is_child_subreaper:1;
	unsigned int		has_child_subreaper:1;

L
Linus Torvalds 已提交
651
	/* POSIX.1b Interval Timers */
652 653
	int			posix_timer_id;
	struct list_head	posix_timers;
L
Linus Torvalds 已提交
654 655

	/* ITIMER_REAL timer for the process */
656
	struct hrtimer real_timer;
657
	struct pid *leader_pid;
658
	ktime_t it_real_incr;
L
Linus Torvalds 已提交
659

660 661 662 663 664 665
	/*
	 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
	 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
	 * values are defined to 0 and 1 respectively
	 */
	struct cpu_itimer it[2];
L
Linus Torvalds 已提交
666

667
	/*
668 669
	 * Thread group totals for process CPU timers.
	 * See thread_group_cputimer(), et al, for details.
670
	 */
671
	struct thread_group_cputimer cputimer;
672 673 674 675 676 677

	/* Earliest-expiration cache. */
	struct task_cputime cputime_expires;

	struct list_head cpu_timers[3];

678
	struct pid *tty_old_pgrp;
679

L
Linus Torvalds 已提交
680 681 682 683 684
	/* boolean value for session group leader */
	int leader;

	struct tty_struct *tty; /* NULL if no tty */

685 686 687
#ifdef CONFIG_SCHED_AUTOGROUP
	struct autogroup *autogroup;
#endif
L
Linus Torvalds 已提交
688 689 690 691 692 693
	/*
	 * Cumulative resource counters for dead threads in the group,
	 * and for reaped dead child processes forked by this group.
	 * Live threads maintain their own counters and add to these
	 * in __exit_signal, except for the group leader.
	 */
694
	seqlock_t stats_lock;
695
	cputime_t utime, stime, cutime, cstime;
696 697
	cputime_t gtime;
	cputime_t cgtime;
698
#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
699
	struct cputime prev_cputime;
700
#endif
L
Linus Torvalds 已提交
701 702
	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
703
	unsigned long inblock, oublock, cinblock, coublock;
J
Jiri Pirko 已提交
704
	unsigned long maxrss, cmaxrss;
705
	struct task_io_accounting ioac;
L
Linus Torvalds 已提交
706

707 708 709 710 711 712 713 714
	/*
	 * Cumulative ns of schedule CPU time fo dead threads in the
	 * group, not including a zombie group leader, (This only differs
	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
	 * other than jiffies.)
	 */
	unsigned long long sum_sched_runtime;

L
Linus Torvalds 已提交
715 716 717 718 719 720 721 722 723 724 725
	/*
	 * We don't bother to synchronize most readers of this at all,
	 * because there is no reader checking a limit that actually needs
	 * to get both rlim_cur and rlim_max atomically, and either one
	 * alone is a single word that can safely be read normally.
	 * getrlimit/setrlimit use task_lock(current->group_leader) to
	 * protect this instead of the siglock, because they really
	 * have no need to disable irqs.
	 */
	struct rlimit rlim[RLIM_NLIMITS];

726 727 728
#ifdef CONFIG_BSD_PROCESS_ACCT
	struct pacct_struct pacct;	/* per-process accounting information */
#endif
729 730 731
#ifdef CONFIG_TASKSTATS
	struct taskstats *stats;
#endif
M
Miloslav Trmac 已提交
732 733
#ifdef CONFIG_AUDIT
	unsigned audit_tty;
734
	unsigned audit_tty_log_passwd;
M
Miloslav Trmac 已提交
735 736
	struct tty_audit_buf *tty_audit_buf;
#endif
737 738
#ifdef CONFIG_CGROUPS
	/*
739 740 741 742 743 744 745
	 * group_rwsem prevents new tasks from entering the threadgroup and
	 * member tasks from exiting,a more specifically, setting of
	 * PF_EXITING.  fork and exit paths are protected with this rwsem
	 * using threadgroup_change_begin/end().  Users which require
	 * threadgroup to remain stable should use threadgroup_[un]lock()
	 * which also takes care of exec path.  Currently, cgroup is the
	 * only user.
746
	 */
747
	struct rw_semaphore group_rwsem;
748
#endif
749

750
	oom_flags_t oom_flags;
751 752 753
	short oom_score_adj;		/* OOM kill score adjustment */
	short oom_score_adj_min;	/* OOM kill score adjustment min value.
					 * Only settable by CAP_SYS_RESOURCE. */
754 755 756 757

	struct mutex cred_guard_mutex;	/* guard against foreign influences on
					 * credential calculations
					 * (notably. ptrace) */
L
Linus Torvalds 已提交
758 759 760 761 762 763
};

/*
 * Bits in flags field of signal_struct.
 */
#define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
764 765
#define SIGNAL_STOP_CONTINUED	0x00000002 /* SIGCONT since WCONTINUED reap */
#define SIGNAL_GROUP_EXIT	0x00000004 /* group exit in progress */
766
#define SIGNAL_GROUP_COREDUMP	0x00000008 /* coredump in progress */
767 768 769 770 771 772
/*
 * Pending notifications to parent.
 */
#define SIGNAL_CLD_STOPPED	0x00000010
#define SIGNAL_CLD_CONTINUED	0x00000020
#define SIGNAL_CLD_MASK		(SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
L
Linus Torvalds 已提交
773

774 775
#define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */

776 777 778 779 780 781 782
/* If true, all threads except ->group_exit_task have pending SIGKILL */
static inline int signal_group_exit(const struct signal_struct *sig)
{
	return	(sig->flags & SIGNAL_GROUP_EXIT) ||
		(sig->group_exit_task != NULL);
}

L
Linus Torvalds 已提交
783 784 785 786 787 788 789
/*
 * Some day this will be a full-fledged user tracking system..
 */
struct user_struct {
	atomic_t __count;	/* reference count */
	atomic_t processes;	/* How many processes does this user have? */
	atomic_t sigpending;	/* How many pending signals does this user have? */
790
#ifdef CONFIG_INOTIFY_USER
R
Robert Love 已提交
791 792 793
	atomic_t inotify_watches; /* How many inotify watches does this user have? */
	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
#endif
794 795 796
#ifdef CONFIG_FANOTIFY
	atomic_t fanotify_listeners;
#endif
797
#ifdef CONFIG_EPOLL
798
	atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
799
#endif
A
Alexey Dobriyan 已提交
800
#ifdef CONFIG_POSIX_MQUEUE
L
Linus Torvalds 已提交
801 802
	/* protected by mq_lock	*/
	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
A
Alexey Dobriyan 已提交
803
#endif
L
Linus Torvalds 已提交
804 805 806 807 808 809 810 811
	unsigned long locked_shm; /* How many pages of mlocked shm ? */

#ifdef CONFIG_KEYS
	struct key *uid_keyring;	/* UID specific keyring */
	struct key *session_keyring;	/* UID's default session keyring */
#endif

	/* Hash table maintenance information */
P
Pavel Emelyanov 已提交
812
	struct hlist_node uidhash_node;
813
	kuid_t uid;
814

815
#ifdef CONFIG_PERF_EVENTS
816 817
	atomic_long_t locked_vm;
#endif
L
Linus Torvalds 已提交
818 819
};

820
extern int uids_sysfs_init(void);
821

822
extern struct user_struct *find_user(kuid_t);
L
Linus Torvalds 已提交
823 824 825 826

extern struct user_struct root_user;
#define INIT_USER (&root_user)

827

L
Linus Torvalds 已提交
828 829 830
struct backing_dev_info;
struct reclaim_state;

831
#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
L
Linus Torvalds 已提交
832 833
struct sched_info {
	/* cumulative counters */
834
	unsigned long pcount;	      /* # of times run on this cpu */
835
	unsigned long long run_delay; /* time spent waiting on a runqueue */
L
Linus Torvalds 已提交
836 837

	/* timestamps */
838 839
	unsigned long long last_arrival,/* when we last ran on a cpu */
			   last_queued;	/* when we were last queued to run */
L
Linus Torvalds 已提交
840
};
841
#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
L
Linus Torvalds 已提交
842

843 844 845 846 847 848 849 850 851 852 853 854 855 856
#ifdef CONFIG_TASK_DELAY_ACCT
struct task_delay_info {
	spinlock_t	lock;
	unsigned int	flags;	/* Private per-task flags */

	/* For each stat XXX, add following, aligned appropriately
	 *
	 * struct timespec XXX_start, XXX_end;
	 * u64 XXX_delay;
	 * u32 XXX_count;
	 *
	 * Atomicity of updates to XXX_delay, XXX_count protected by
	 * single lock above (split into XXX_lock if contention is an issue).
	 */
857 858 859 860 861 862

	/*
	 * XXX_count is incremented on every XXX operation, the delay
	 * associated with the operation is added to XXX_delay.
	 * XXX_delay contains the accumulated delay time in nanoseconds.
	 */
863
	u64 blkio_start;	/* Shared by blkio, swapin */
864 865 866 867 868 869
	u64 blkio_delay;	/* wait for sync block io completion */
	u64 swapin_delay;	/* wait for swapin block io completion */
	u32 blkio_count;	/* total count of the number of sync block */
				/* io operations performed */
	u32 swapin_count;	/* total count of the number of swapin block */
				/* io operations performed */
870

871
	u64 freepages_start;
872 873
	u64 freepages_delay;	/* wait for memory reclaim */
	u32 freepages_count;	/* total count of memory reclaim */
874
};
875 876 877 878 879 880 881 882 883 884 885
#endif	/* CONFIG_TASK_DELAY_ACCT */

static inline int sched_info_on(void)
{
#ifdef CONFIG_SCHEDSTATS
	return 1;
#elif defined(CONFIG_TASK_DELAY_ACCT)
	extern int delayacct_on;
	return delayacct_on;
#else
	return 0;
886
#endif
887
}
888

I
Ingo Molnar 已提交
889 890 891 892 893
enum cpu_idle_type {
	CPU_IDLE,
	CPU_NOT_IDLE,
	CPU_NEWLY_IDLE,
	CPU_MAX_IDLE_TYPES
L
Linus Torvalds 已提交
894 895
};

896
/*
897
 * Increase resolution of cpu_capacity calculations
898
 */
899 900
#define SCHED_CAPACITY_SHIFT	10
#define SCHED_CAPACITY_SCALE	(1L << SCHED_CAPACITY_SHIFT)
L
Linus Torvalds 已提交
901

902 903 904
/*
 * sched-domains (multiprocessor balancing) declarations:
 */
905
#ifdef CONFIG_SMP
P
Peter Zijlstra 已提交
906 907 908 909
#define SD_LOAD_BALANCE		0x0001	/* Do load balancing on this domain. */
#define SD_BALANCE_NEWIDLE	0x0002	/* Balance when about to become idle */
#define SD_BALANCE_EXEC		0x0004	/* Balance on exec */
#define SD_BALANCE_FORK		0x0008	/* Balance on fork, clone */
910
#define SD_BALANCE_WAKE		0x0010  /* Balance on wakeup */
P
Peter Zijlstra 已提交
911
#define SD_WAKE_AFFINE		0x0020	/* Wake task to waking CPU */
912
#define SD_SHARE_CPUCAPACITY	0x0080	/* Domain members share cpu power */
913
#define SD_SHARE_POWERDOMAIN	0x0100	/* Domain members share power domain */
P
Peter Zijlstra 已提交
914 915
#define SD_SHARE_PKG_RESOURCES	0x0200	/* Domain members share cpu pkg resources */
#define SD_SERIALIZE		0x0400	/* Only a single load balancing instance */
916
#define SD_ASYM_PACKING		0x0800  /* Place busy groups earlier in the domain */
P
Peter Zijlstra 已提交
917
#define SD_PREFER_SIBLING	0x1000	/* Prefer to place tasks in a sibling domain */
918
#define SD_OVERLAP		0x2000	/* sched_domains of this level overlap */
919
#define SD_NUMA			0x4000	/* cross-node balancing */
920

921
#ifdef CONFIG_SCHED_SMT
G
Guenter Roeck 已提交
922
static inline int cpu_smt_flags(void)
923
{
924
	return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES;
925 926 927 928
}
#endif

#ifdef CONFIG_SCHED_MC
G
Guenter Roeck 已提交
929
static inline int cpu_core_flags(void)
930 931 932 933 934 935
{
	return SD_SHARE_PKG_RESOURCES;
}
#endif

#ifdef CONFIG_NUMA
G
Guenter Roeck 已提交
936
static inline int cpu_numa_flags(void)
937 938 939 940
{
	return SD_NUMA;
}
#endif
941

942 943 944 945 946 947 948 949
struct sched_domain_attr {
	int relax_domain_level;
};

#define SD_ATTR_INIT	(struct sched_domain_attr) {	\
	.relax_domain_level = -1,			\
}

950 951
extern int sched_domain_level_max;

952 953
struct sched_group;

L
Linus Torvalds 已提交
954 955 956
struct sched_domain {
	/* These fields must be setup */
	struct sched_domain *parent;	/* top domain must be null terminated */
957
	struct sched_domain *child;	/* bottom domain must be null terminated */
L
Linus Torvalds 已提交
958 959 960 961 962 963
	struct sched_group *groups;	/* the balancing groups of the domain */
	unsigned long min_interval;	/* Minimum balance interval ms */
	unsigned long max_interval;	/* Maximum balance interval ms */
	unsigned int busy_factor;	/* less balancing by factor if busy */
	unsigned int imbalance_pct;	/* No balance until over watermark */
	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
N
Nick Piggin 已提交
964 965 966 967
	unsigned int busy_idx;
	unsigned int idle_idx;
	unsigned int newidle_idx;
	unsigned int wake_idx;
N
Nick Piggin 已提交
968
	unsigned int forkexec_idx;
P
Peter Zijlstra 已提交
969
	unsigned int smt_gain;
V
Vincent Guittot 已提交
970 971

	int nohz_idle;			/* NOHZ IDLE status */
L
Linus Torvalds 已提交
972
	int flags;			/* See SD_* */
973
	int level;
L
Linus Torvalds 已提交
974 975 976 977 978 979

	/* Runtime fields. */
	unsigned long last_balance;	/* init to jiffies. units in jiffies */
	unsigned int balance_interval;	/* initialise to 1. units in ms. */
	unsigned int nr_balance_failed; /* initialise to 0 */

980
	/* idle_balance() stats */
981
	u64 max_newidle_lb_cost;
982
	unsigned long next_decay_max_lb_cost;
P
Peter Zijlstra 已提交
983

L
Linus Torvalds 已提交
984 985
#ifdef CONFIG_SCHEDSTATS
	/* load_balance() stats */
986 987 988 989 990 991 992 993
	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
L
Linus Torvalds 已提交
994 995

	/* Active load balancing */
996 997 998
	unsigned int alb_count;
	unsigned int alb_failed;
	unsigned int alb_pushed;
L
Linus Torvalds 已提交
999

1000
	/* SD_BALANCE_EXEC stats */
1001 1002 1003
	unsigned int sbe_count;
	unsigned int sbe_balanced;
	unsigned int sbe_pushed;
L
Linus Torvalds 已提交
1004

1005
	/* SD_BALANCE_FORK stats */
1006 1007 1008
	unsigned int sbf_count;
	unsigned int sbf_balanced;
	unsigned int sbf_pushed;
1009

L
Linus Torvalds 已提交
1010
	/* try_to_wake_up() stats */
1011 1012 1013
	unsigned int ttwu_wake_remote;
	unsigned int ttwu_move_affine;
	unsigned int ttwu_move_balance;
L
Linus Torvalds 已提交
1014
#endif
1015 1016 1017
#ifdef CONFIG_SCHED_DEBUG
	char *name;
#endif
1018 1019 1020 1021
	union {
		void *private;		/* used during construction */
		struct rcu_head rcu;	/* used during destruction */
	};
1022

1023
	unsigned int span_weight;
1024 1025 1026 1027 1028 1029 1030 1031
	/*
	 * Span of all CPUs in this domain.
	 *
	 * NOTE: this field is variable length. (Allocated dynamically
	 * by attaching extra space to the end of the structure,
	 * depending on how many CPUs the kernel has booted up with)
	 */
	unsigned long span[0];
L
Linus Torvalds 已提交
1032 1033
};

1034 1035
static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
{
1036
	return to_cpumask(sd->span);
1037 1038
}

1039
extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1040
				    struct sched_domain_attr *dattr_new);
P
Paul Jackson 已提交
1041

1042 1043 1044 1045
/* Allocate an array of sched domains, for partition_sched_domains(). */
cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);

1046 1047
bool cpus_share_cache(int this_cpu, int that_cpu);

1048
typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
G
Guenter Roeck 已提交
1049
typedef int (*sched_domain_flags_f)(void);
1050 1051 1052 1053 1054 1055

#define SDTL_OVERLAP	0x01

struct sd_data {
	struct sched_domain **__percpu sd;
	struct sched_group **__percpu sg;
1056
	struct sched_group_capacity **__percpu sgc;
1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072
};

struct sched_domain_topology_level {
	sched_domain_mask_f mask;
	sched_domain_flags_f sd_flags;
	int		    flags;
	int		    numa_level;
	struct sd_data      data;
#ifdef CONFIG_SCHED_DEBUG
	char                *name;
#endif
};

extern struct sched_domain_topology_level *sched_domain_topology;

extern void set_sched_topology(struct sched_domain_topology_level *tl);
1073
extern void wake_up_if_idle(int cpu);
1074 1075 1076 1077 1078 1079 1080

#ifdef CONFIG_SCHED_DEBUG
# define SD_INIT_NAME(type)		.name = #type
#else
# define SD_INIT_NAME(type)
#endif

1081
#else /* CONFIG_SMP */
L
Linus Torvalds 已提交
1082

1083
struct sched_domain_attr;
1084

1085
static inline void
1086
partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1087 1088
			struct sched_domain_attr *dattr_new)
{
1089
}
1090 1091 1092 1093 1094 1095

static inline bool cpus_share_cache(int this_cpu, int that_cpu)
{
	return true;
}

1096
#endif	/* !CONFIG_SMP */
L
Linus Torvalds 已提交
1097

1098

L
Linus Torvalds 已提交
1099 1100 1101
struct io_context;			/* See blkdev.h */


1102
#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1103
extern void prefetch_stack(struct task_struct *t);
1104 1105 1106
#else
static inline void prefetch_stack(struct task_struct *t) { }
#endif
L
Linus Torvalds 已提交
1107 1108 1109

struct audit_context;		/* See audit.c */
struct mempolicy;
1110
struct pipe_inode_info;
1111
struct uts_namespace;
L
Linus Torvalds 已提交
1112

I
Ingo Molnar 已提交
1113
struct load_weight {
1114 1115
	unsigned long weight;
	u32 inv_weight;
I
Ingo Molnar 已提交
1116 1117
};

1118
struct sched_avg {
1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129
	u64 last_runnable_update;
	s64 decay_count;
	/*
	 * utilization_avg_contrib describes the amount of time that a
	 * sched_entity is running on a CPU. It is based on running_avg_sum
	 * and is scaled in the range [0..SCHED_LOAD_SCALE].
	 * load_avg_contrib described the amount of time that a sched_entity
	 * is runnable on a rq. It is based on both runnable_avg_sum and the
	 * weight of the task.
	 */
	unsigned long load_avg_contrib, utilization_avg_contrib;
1130 1131
	/*
	 * These sums represent an infinite geometric series and so are bound
1132
	 * above by 1024/(1-y).  Thus we only need a u32 to store them for all
1133
	 * choices of y < 1-2^(-32)*1024.
1134 1135 1136 1137 1138
	 * running_avg_sum reflects the time that the sched_entity is
	 * effectively running on the CPU.
	 * runnable_avg_sum represents the amount of time a sched_entity is on
	 * a runqueue which includes the running time that is monitored by
	 * running_avg_sum.
1139
	 */
1140
	u32 runnable_avg_sum, avg_period, running_avg_sum;
1141 1142
};

1143
#ifdef CONFIG_SCHEDSTATS
1144
struct sched_statistics {
I
Ingo Molnar 已提交
1145
	u64			wait_start;
1146
	u64			wait_max;
1147 1148
	u64			wait_count;
	u64			wait_sum;
1149 1150
	u64			iowait_count;
	u64			iowait_sum;
1151

I
Ingo Molnar 已提交
1152 1153
	u64			sleep_start;
	u64			sleep_max;
1154 1155 1156
	s64			sum_sleep_runtime;

	u64			block_start;
I
Ingo Molnar 已提交
1157 1158
	u64			block_max;
	u64			exec_max;
I
Ingo Molnar 已提交
1159
	u64			slice_max;
1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175

	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;
1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193
};
#endif

struct sched_entity {
	struct load_weight	load;		/* for load-balancing */
	struct rb_node		run_node;
	struct list_head	group_node;
	unsigned int		on_rq;

	u64			exec_start;
	u64			sum_exec_runtime;
	u64			vruntime;
	u64			prev_sum_exec_runtime;

	u64			nr_migrations;

#ifdef CONFIG_SCHEDSTATS
	struct sched_statistics statistics;
1194 1195
#endif

I
Ingo Molnar 已提交
1196
#ifdef CONFIG_FAIR_GROUP_SCHED
P
Peter Zijlstra 已提交
1197
	int			depth;
I
Ingo Molnar 已提交
1198 1199 1200 1201 1202 1203
	struct sched_entity	*parent;
	/* rq on which this entity is (to be) queued: */
	struct cfs_rq		*cfs_rq;
	/* rq "owned" by this entity/group: */
	struct cfs_rq		*my_q;
#endif
1204

1205
#ifdef CONFIG_SMP
1206
	/* Per-entity load-tracking */
1207 1208
	struct sched_avg	avg;
#endif
I
Ingo Molnar 已提交
1209
};
1210

P
Peter Zijlstra 已提交
1211 1212
struct sched_rt_entity {
	struct list_head run_list;
1213
	unsigned long timeout;
1214
	unsigned long watchdog_stamp;
1215
	unsigned int time_slice;
P
Peter Zijlstra 已提交
1216

1217
	struct sched_rt_entity *back;
1218
#ifdef CONFIG_RT_GROUP_SCHED
P
Peter Zijlstra 已提交
1219 1220 1221 1222 1223 1224
	struct sched_rt_entity	*parent;
	/* rq on which this entity is (to be) queued: */
	struct rt_rq		*rt_rq;
	/* rq "owned" by this entity/group: */
	struct rt_rq		*my_q;
#endif
P
Peter Zijlstra 已提交
1225 1226
};

1227 1228 1229 1230 1231
struct sched_dl_entity {
	struct rb_node	rb_node;

	/*
	 * Original scheduling parameters. Copied here from sched_attr
1232 1233
	 * during sched_setattr(), they will remain the same until
	 * the next sched_setattr().
1234 1235 1236
	 */
	u64 dl_runtime;		/* maximum runtime for each instance	*/
	u64 dl_deadline;	/* relative deadline of each instance	*/
1237
	u64 dl_period;		/* separation of two instances (period) */
1238
	u64 dl_bw;		/* dl_runtime / dl_deadline		*/
1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258

	/*
	 * 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.
	 */
	s64 runtime;		/* remaining runtime for this instance	*/
	u64 deadline;		/* absolute deadline for this instance	*/
	unsigned int flags;	/* specifying the scheduler behaviour	*/

	/*
	 * 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.
	 *
	 * @dl_new tells if a new instance arrived. If so we must
	 * start executing it with full runtime and reset its absolute
	 * deadline;
1259 1260 1261
	 *
	 * @dl_boosted tells if we are boosted due to DI. If so we are
	 * outside bandwidth enforcement mechanism (but only until we
1262 1263 1264 1265
	 * exit the critical section);
	 *
	 * @dl_yielded tells if task gave up the cpu before consuming
	 * all its available runtime during the last job.
1266
	 */
1267
	int dl_throttled, dl_new, dl_boosted, dl_yielded;
1268 1269 1270 1271 1272 1273 1274

	/*
	 * Bandwidth enforcement timer. Each -deadline task has its
	 * own bandwidth to be enforced, thus we need one timer per task.
	 */
	struct hrtimer dl_timer;
};
1275

1276 1277 1278 1279 1280 1281 1282
union rcu_special {
	struct {
		bool blocked;
		bool need_qs;
	} b;
	short s;
};
1283 1284
struct rcu_node;

P
Peter Zijlstra 已提交
1285 1286 1287
enum perf_event_task_context {
	perf_invalid_context = -1,
	perf_hw_context = 0,
1288
	perf_sw_context,
P
Peter Zijlstra 已提交
1289 1290 1291
	perf_nr_task_contexts,
};

L
Linus Torvalds 已提交
1292 1293
struct task_struct {
	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
R
Roman Zippel 已提交
1294
	void *stack;
L
Linus Torvalds 已提交
1295
	atomic_t usage;
1296 1297
	unsigned int flags;	/* per process flags, defined below */
	unsigned int ptrace;
L
Linus Torvalds 已提交
1298

1299
#ifdef CONFIG_SMP
P
Peter Zijlstra 已提交
1300
	struct llist_node wake_entry;
P
Peter Zijlstra 已提交
1301
	int on_cpu;
1302 1303 1304
	struct task_struct *last_wakee;
	unsigned long wakee_flips;
	unsigned long wakee_flip_decay_ts;
1305 1306

	int wake_cpu;
1307
#endif
P
Peter Zijlstra 已提交
1308
	int on_rq;
1309

1310
	int prio, static_prio, normal_prio;
1311
	unsigned int rt_priority;
1312
	const struct sched_class *sched_class;
I
Ingo Molnar 已提交
1313
	struct sched_entity se;
P
Peter Zijlstra 已提交
1314
	struct sched_rt_entity rt;
P
Peter Zijlstra 已提交
1315 1316 1317
#ifdef CONFIG_CGROUP_SCHED
	struct task_group *sched_task_group;
#endif
1318
	struct sched_dl_entity dl;
L
Linus Torvalds 已提交
1319

1320 1321 1322 1323 1324
#ifdef CONFIG_PREEMPT_NOTIFIERS
	/* list of struct preempt_notifier: */
	struct hlist_head preempt_notifiers;
#endif

1325
#ifdef CONFIG_BLK_DEV_IO_TRACE
1326
	unsigned int btrace_seq;
1327
#endif
L
Linus Torvalds 已提交
1328

1329
	unsigned int policy;
1330
	int nr_cpus_allowed;
L
Linus Torvalds 已提交
1331 1332
	cpumask_t cpus_allowed;

P
Paul E. McKenney 已提交
1333
#ifdef CONFIG_PREEMPT_RCU
P
Paul E. McKenney 已提交
1334
	int rcu_read_lock_nesting;
1335
	union rcu_special rcu_read_unlock_special;
1336
	struct list_head rcu_node_entry;
P
Paul E. McKenney 已提交
1337
#endif /* #ifdef CONFIG_PREEMPT_RCU */
1338
#ifdef CONFIG_PREEMPT_RCU
P
Paul E. McKenney 已提交
1339
	struct rcu_node *rcu_blocked_node;
1340
#endif /* #ifdef CONFIG_PREEMPT_RCU */
P
Paul E. McKenney 已提交
1341 1342 1343 1344
#ifdef CONFIG_TASKS_RCU
	unsigned long rcu_tasks_nvcsw;
	bool rcu_tasks_holdout;
	struct list_head rcu_tasks_holdout_list;
1345
	int rcu_tasks_idle_cpu;
P
Paul E. McKenney 已提交
1346
#endif /* #ifdef CONFIG_TASKS_RCU */
P
Paul E. McKenney 已提交
1347

1348
#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
L
Linus Torvalds 已提交
1349 1350 1351 1352
	struct sched_info sched_info;
#endif

	struct list_head tasks;
1353
#ifdef CONFIG_SMP
1354
	struct plist_node pushable_tasks;
1355
	struct rb_node pushable_dl_tasks;
1356
#endif
L
Linus Torvalds 已提交
1357 1358

	struct mm_struct *mm, *active_mm;
1359 1360 1361
#ifdef CONFIG_COMPAT_BRK
	unsigned brk_randomized:1;
#endif
D
Davidlohr Bueso 已提交
1362 1363 1364
	/* per-thread vma caching */
	u32 vmacache_seqnum;
	struct vm_area_struct *vmacache[VMACACHE_SIZE];
1365 1366 1367
#if defined(SPLIT_RSS_COUNTING)
	struct task_rss_stat	rss_stat;
#endif
L
Linus Torvalds 已提交
1368
/* task state */
1369
	int exit_state;
L
Linus Torvalds 已提交
1370 1371
	int exit_code, exit_signal;
	int pdeath_signal;  /*  The signal sent when the parent dies  */
1372
	unsigned int jobctl;	/* JOBCTL_*, siglock protected */
1373 1374

	/* Used for emulating ABI behavior of previous Linux versions */
1375
	unsigned int personality;
1376

1377 1378
	unsigned in_execve:1;	/* Tell the LSMs that the process is doing an
				 * execve */
1379 1380
	unsigned in_iowait:1;

1381 1382
	/* Revert to default priority/policy when forking */
	unsigned sched_reset_on_fork:1;
1383
	unsigned sched_contributes_to_load:1;
1384

1385 1386 1387 1388
#ifdef CONFIG_MEMCG_KMEM
	unsigned memcg_kmem_skip_account:1;
#endif

1389 1390
	unsigned long atomic_flags; /* Flags needing atomic access. */

1391 1392
	struct restart_block restart_block;

L
Linus Torvalds 已提交
1393 1394
	pid_t pid;
	pid_t tgid;
1395

1396
#ifdef CONFIG_CC_STACKPROTECTOR
1397 1398
	/* Canary value for the -fstack-protector gcc feature */
	unsigned long stack_canary;
1399
#endif
1400
	/*
L
Linus Torvalds 已提交
1401
	 * pointers to (original) parent process, youngest child, younger sibling,
1402
	 * older sibling, respectively.  (p->father can be replaced with
R
Roland McGrath 已提交
1403
	 * p->real_parent->pid)
L
Linus Torvalds 已提交
1404
	 */
1405 1406
	struct task_struct __rcu *real_parent; /* real parent process */
	struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */
L
Linus Torvalds 已提交
1407
	/*
R
Roland McGrath 已提交
1408
	 * children/sibling forms the list of my natural children
L
Linus Torvalds 已提交
1409 1410 1411 1412 1413
	 */
	struct list_head children;	/* list of my children */
	struct list_head sibling;	/* linkage in my parent's children list */
	struct task_struct *group_leader;	/* threadgroup leader */

R
Roland McGrath 已提交
1414 1415 1416 1417 1418 1419 1420 1421
	/*
	 * ptraced is the list of tasks this task is using ptrace on.
	 * This includes both natural children and PTRACE_ATTACH targets.
	 * p->ptrace_entry is p's link on the p->parent->ptraced list.
	 */
	struct list_head ptraced;
	struct list_head ptrace_entry;

L
Linus Torvalds 已提交
1422
	/* PID/PID hash table linkage. */
1423
	struct pid_link pids[PIDTYPE_MAX];
O
Oleg Nesterov 已提交
1424
	struct list_head thread_group;
1425
	struct list_head thread_node;
L
Linus Torvalds 已提交
1426 1427 1428 1429 1430

	struct completion *vfork_done;		/* for vfork() */
	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */

1431
	cputime_t utime, stime, utimescaled, stimescaled;
1432
	cputime_t gtime;
1433
#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
1434
	struct cputime prev_cputime;
1435 1436 1437 1438 1439 1440 1441 1442 1443
#endif
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
	seqlock_t vtime_seqlock;
	unsigned long long vtime_snap;
	enum {
		VTIME_SLEEPING = 0,
		VTIME_USER,
		VTIME_SYS,
	} vtime_snap_whence;
1444
#endif
L
Linus Torvalds 已提交
1445
	unsigned long nvcsw, nivcsw; /* context switch counts */
1446
	u64 start_time;		/* monotonic time in nsec */
1447
	u64 real_start_time;	/* boot based time in nsec */
L
Linus Torvalds 已提交
1448 1449 1450
/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
	unsigned long min_flt, maj_flt;

1451
	struct task_cputime cputime_expires;
L
Linus Torvalds 已提交
1452 1453 1454
	struct list_head cpu_timers[3];

/* process credentials */
A
Arnd Bergmann 已提交
1455
	const struct cred __rcu *real_cred; /* objective and real subjective task
1456
					 * credentials (COW) */
A
Arnd Bergmann 已提交
1457
	const struct cred __rcu *cred;	/* effective (overridable) subjective task
1458
					 * credentials (COW) */
1459 1460 1461
	char comm[TASK_COMM_LEN]; /* executable name excluding path
				     - access with [gs]et_task_comm (which lock
				       it with task_lock())
1462
				     - initialized normally by setup_new_exec */
L
Linus Torvalds 已提交
1463 1464
/* file system info */
	int link_count, total_link_count;
1465
#ifdef CONFIG_SYSVIPC
L
Linus Torvalds 已提交
1466 1467
/* ipc stuff */
	struct sysv_sem sysvsem;
1468
	struct sysv_shm sysvshm;
1469
#endif
1470
#ifdef CONFIG_DETECT_HUNG_TASK
1471 1472 1473
/* hung task detection */
	unsigned long last_switch_count;
#endif
L
Linus Torvalds 已提交
1474 1475 1476 1477 1478 1479
/* CPU-specific state of this task */
	struct thread_struct thread;
/* filesystem information */
	struct fs_struct *fs;
/* open file information */
	struct files_struct *files;
1480
/* namespaces */
S
Serge E. Hallyn 已提交
1481
	struct nsproxy *nsproxy;
L
Linus Torvalds 已提交
1482 1483 1484 1485 1486
/* signal handlers */
	struct signal_struct *signal;
	struct sighand_struct *sighand;

	sigset_t blocked, real_blocked;
1487
	sigset_t saved_sigmask;	/* restored if set_restore_sigmask() was used */
L
Linus Torvalds 已提交
1488 1489 1490 1491 1492 1493 1494
	struct sigpending pending;

	unsigned long sas_ss_sp;
	size_t sas_ss_size;
	int (*notifier)(void *priv);
	void *notifier_data;
	sigset_t *notifier_mask;
1495
	struct callback_head *task_works;
1496

L
Linus Torvalds 已提交
1497
	struct audit_context *audit_context;
A
Al Viro 已提交
1498
#ifdef CONFIG_AUDITSYSCALL
1499
	kuid_t loginuid;
1500
	unsigned int sessionid;
A
Al Viro 已提交
1501
#endif
1502
	struct seccomp seccomp;
L
Linus Torvalds 已提交
1503 1504 1505 1506

/* Thread group tracking */
   	u32 parent_exec_id;
   	u32 self_exec_id;
1507 1508
/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
 * mempolicy */
L
Linus Torvalds 已提交
1509 1510
	spinlock_t alloc_lock;

1511
	/* Protection of the PI data structures: */
1512
	raw_spinlock_t pi_lock;
1513

I
Ingo Molnar 已提交
1514 1515
#ifdef CONFIG_RT_MUTEXES
	/* PI waiters blocked on a rt_mutex held by this task */
1516 1517
	struct rb_root pi_waiters;
	struct rb_node *pi_waiters_leftmost;
I
Ingo Molnar 已提交
1518 1519 1520 1521
	/* Deadlock detection and priority inheritance handling */
	struct rt_mutex_waiter *pi_blocked_on;
#endif

1522 1523 1524 1525
#ifdef CONFIG_DEBUG_MUTEXES
	/* mutex deadlock detection */
	struct mutex_waiter *blocked_on;
#endif
1526 1527 1528 1529
#ifdef CONFIG_TRACE_IRQFLAGS
	unsigned int irq_events;
	unsigned long hardirq_enable_ip;
	unsigned long hardirq_disable_ip;
1530
	unsigned int hardirq_enable_event;
1531
	unsigned int hardirq_disable_event;
1532 1533
	int hardirqs_enabled;
	int hardirq_context;
1534 1535
	unsigned long softirq_disable_ip;
	unsigned long softirq_enable_ip;
1536
	unsigned int softirq_disable_event;
1537
	unsigned int softirq_enable_event;
1538
	int softirqs_enabled;
1539 1540
	int softirq_context;
#endif
I
Ingo Molnar 已提交
1541
#ifdef CONFIG_LOCKDEP
1542
# define MAX_LOCK_DEPTH 48UL
I
Ingo Molnar 已提交
1543 1544 1545
	u64 curr_chain_key;
	int lockdep_depth;
	unsigned int lockdep_recursion;
1546
	struct held_lock held_locks[MAX_LOCK_DEPTH];
1547
	gfp_t lockdep_reclaim_gfp;
I
Ingo Molnar 已提交
1548
#endif
1549

L
Linus Torvalds 已提交
1550 1551 1552
/* journalling filesystem info */
	void *journal_info;

1553
/* stacked block device info */
1554
	struct bio_list *bio_list;
1555

1556 1557 1558 1559 1560
#ifdef CONFIG_BLOCK
/* stack plugging */
	struct blk_plug *plug;
#endif

L
Linus Torvalds 已提交
1561 1562 1563 1564 1565 1566 1567 1568 1569
/* VM state */
	struct reclaim_state *reclaim_state;

	struct backing_dev_info *backing_dev_info;

	struct io_context *io_context;

	unsigned long ptrace_message;
	siginfo_t *last_siginfo; /* For ptrace use.  */
1570
	struct task_io_accounting ioac;
1571
#if defined(CONFIG_TASK_XACCT)
L
Linus Torvalds 已提交
1572 1573
	u64 acct_rss_mem1;	/* accumulated rss usage */
	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1574
	cputime_t acct_timexpd;	/* stime + utime since last update */
L
Linus Torvalds 已提交
1575 1576
#endif
#ifdef CONFIG_CPUSETS
1577
	nodemask_t mems_allowed;	/* Protected by alloc_lock */
1578
	seqcount_t mems_allowed_seq;	/* Seqence no to catch updates */
1579
	int cpuset_mem_spread_rotor;
1580
	int cpuset_slab_spread_rotor;
L
Linus Torvalds 已提交
1581
#endif
1582
#ifdef CONFIG_CGROUPS
1583
	/* Control Group info protected by css_set_lock */
A
Arnd Bergmann 已提交
1584
	struct css_set __rcu *cgroups;
1585 1586
	/* cg_list protected by css_set_lock and tsk->alloc_lock */
	struct list_head cg_list;
1587
#endif
1588
#ifdef CONFIG_FUTEX
1589
	struct robust_list_head __user *robust_list;
1590 1591 1592
#ifdef CONFIG_COMPAT
	struct compat_robust_list_head __user *compat_robust_list;
#endif
1593 1594
	struct list_head pi_state_list;
	struct futex_pi_state *pi_state_cache;
1595
#endif
1596
#ifdef CONFIG_PERF_EVENTS
P
Peter Zijlstra 已提交
1597
	struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1598 1599
	struct mutex perf_event_mutex;
	struct list_head perf_event_list;
1600
#endif
1601 1602 1603
#ifdef CONFIG_DEBUG_PREEMPT
	unsigned long preempt_disable_ip;
#endif
1604
#ifdef CONFIG_NUMA
1605
	struct mempolicy *mempolicy;	/* Protected by alloc_lock */
1606
	short il_next;
1607
	short pref_node_fork;
1608
#endif
1609 1610 1611
#ifdef CONFIG_NUMA_BALANCING
	int numa_scan_seq;
	unsigned int numa_scan_period;
1612
	unsigned int numa_scan_period_max;
1613
	int numa_preferred_nid;
1614
	unsigned long numa_migrate_retry;
1615
	u64 node_stamp;			/* migration stamp  */
1616 1617
	u64 last_task_numa_placement;
	u64 last_sum_exec_runtime;
1618
	struct callback_head numa_work;
1619

1620 1621 1622
	struct list_head numa_entry;
	struct numa_group *numa_group;

1623
	/*
1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635
	 * 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.
1636
	 */
1637
	unsigned long *numa_faults;
1638
	unsigned long total_numa_faults;
1639

1640 1641
	/*
	 * numa_faults_locality tracks if faults recorded during the last
1642 1643 1644
	 * 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
1645
	 */
1646
	unsigned long numa_faults_locality[3];
1647

I
Ingo Molnar 已提交
1648
	unsigned long numa_pages_migrated;
1649 1650
#endif /* CONFIG_NUMA_BALANCING */

I
Ingo Molnar 已提交
1651
	struct rcu_head rcu;
1652 1653 1654 1655 1656

	/*
	 * cache last used pipe for splice
	 */
	struct pipe_inode_info *splice_pipe;
1657 1658 1659

	struct page_frag task_frag;

1660 1661
#ifdef	CONFIG_TASK_DELAY_ACCT
	struct task_delay_info *delays;
1662 1663 1664
#endif
#ifdef CONFIG_FAULT_INJECTION
	int make_it_fail;
1665
#endif
1666 1667 1668 1669 1670 1671
	/*
	 * when (nr_dirtied >= nr_dirtied_pause), it's time to call
	 * balance_dirty_pages() for some dirty throttling pause
	 */
	int nr_dirtied;
	int nr_dirtied_pause;
1672
	unsigned long dirty_paused_when; /* start of a write-and-pause period */
1673

A
Arjan van de Ven 已提交
1674 1675 1676 1677
#ifdef CONFIG_LATENCYTOP
	int latency_record_count;
	struct latency_record latency_record[LT_SAVECOUNT];
#endif
1678 1679 1680 1681 1682 1683
	/*
	 * time slack values; these are used to round up poll() and
	 * select() etc timeout values. These are in nanoseconds.
	 */
	unsigned long timer_slack_ns;
	unsigned long default_timer_slack_ns;
1684

1685 1686 1687
#ifdef CONFIG_KASAN
	unsigned int kasan_depth;
#endif
1688
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
D
Daniel Mack 已提交
1689
	/* Index of current stored address in ret_stack */
1690 1691 1692
	int curr_ret_stack;
	/* Stack of return addresses for return function tracing */
	struct ftrace_ret_stack	*ret_stack;
1693 1694
	/* time stamp for last schedule */
	unsigned long long ftrace_timestamp;
1695 1696 1697 1698 1699
	/*
	 * Number of functions that haven't been traced
	 * because of depth overrun.
	 */
	atomic_t trace_overrun;
1700 1701
	/* Pause for the tracing */
	atomic_t tracing_graph_pause;
1702
#endif
1703 1704 1705
#ifdef CONFIG_TRACING
	/* state flags for use by tracers */
	unsigned long trace;
1706
	/* bitmask and counter of trace recursion */
1707 1708
	unsigned long trace_recursion;
#endif /* CONFIG_TRACING */
1709
#ifdef CONFIG_MEMCG
1710
	struct memcg_oom_info {
1711 1712 1713
		struct mem_cgroup *memcg;
		gfp_t gfp_mask;
		int order;
1714 1715
		unsigned int may_oom:1;
	} memcg_oom;
1716
#endif
1717 1718 1719
#ifdef CONFIG_UPROBES
	struct uprobe_task *utask;
#endif
K
Kent Overstreet 已提交
1720 1721 1722 1723
#if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
	unsigned int	sequential_io;
	unsigned int	sequential_io_avg;
#endif
P
Peter Zijlstra 已提交
1724 1725 1726
#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
	unsigned long	task_state_change;
#endif
L
Linus Torvalds 已提交
1727 1728
};

1729
/* Future-safe accessor for struct task_struct's cpus_allowed. */
1730
#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1731

1732 1733
#define TNF_MIGRATED	0x01
#define TNF_NO_GROUP	0x02
1734
#define TNF_SHARED	0x04
1735
#define TNF_FAULT_LOCAL	0x08
1736
#define TNF_MIGRATE_FAIL 0x10
1737

1738
#ifdef CONFIG_NUMA_BALANCING
1739
extern void task_numa_fault(int last_node, int node, int pages, int flags);
1740
extern pid_t task_numa_group_id(struct task_struct *p);
1741
extern void set_numabalancing_state(bool enabled);
1742
extern void task_numa_free(struct task_struct *p);
1743 1744
extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page,
					int src_nid, int dst_cpu);
1745
#else
1746
static inline void task_numa_fault(int last_node, int node, int pages,
1747
				   int flags)
1748 1749
{
}
1750 1751 1752 1753
static inline pid_t task_numa_group_id(struct task_struct *p)
{
	return 0;
}
1754 1755 1756
static inline void set_numabalancing_state(bool enabled)
{
}
1757 1758 1759
static inline void task_numa_free(struct task_struct *p)
{
}
1760 1761 1762 1763 1764
static inline bool should_numa_migrate_memory(struct task_struct *p,
				struct page *page, int src_nid, int dst_cpu)
{
	return true;
}
1765 1766
#endif

A
Alexey Dobriyan 已提交
1767
static inline struct pid *task_pid(struct task_struct *task)
1768 1769 1770 1771
{
	return task->pids[PIDTYPE_PID].pid;
}

A
Alexey Dobriyan 已提交
1772
static inline struct pid *task_tgid(struct task_struct *task)
1773 1774 1775 1776
{
	return task->group_leader->pids[PIDTYPE_PID].pid;
}

1777 1778 1779 1780 1781
/*
 * Without tasklist or rcu lock it is not safe to dereference
 * the result of task_pgrp/task_session even if task == current,
 * we can race with another thread doing sys_setsid/sys_setpgid.
 */
A
Alexey Dobriyan 已提交
1782
static inline struct pid *task_pgrp(struct task_struct *task)
1783 1784 1785 1786
{
	return task->group_leader->pids[PIDTYPE_PGID].pid;
}

A
Alexey Dobriyan 已提交
1787
static inline struct pid *task_session(struct task_struct *task)
1788 1789 1790 1791
{
	return task->group_leader->pids[PIDTYPE_SID].pid;
}

1792 1793 1794 1795 1796 1797 1798
struct pid_namespace;

/*
 * 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
1799 1800
 * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
 *                     current.
1801 1802 1803 1804 1805 1806
 * task_xid_nr_ns()  : id seen from the ns specified;
 *
 * set_task_vxid()   : assigns a virtual id to a task;
 *
 * see also pid_nr() etc in include/linux/pid.h
 */
1807 1808
pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
			struct pid_namespace *ns);
1809

A
Alexey Dobriyan 已提交
1810
static inline pid_t task_pid_nr(struct task_struct *tsk)
1811 1812 1813 1814
{
	return tsk->pid;
}

1815 1816 1817 1818 1819
static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
					struct pid_namespace *ns)
{
	return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
}
1820 1821 1822

static inline pid_t task_pid_vnr(struct task_struct *tsk)
{
1823
	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1824 1825 1826
}


A
Alexey Dobriyan 已提交
1827
static inline pid_t task_tgid_nr(struct task_struct *tsk)
1828 1829 1830 1831
{
	return tsk->tgid;
}

1832
pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1833 1834 1835 1836 1837 1838 1839

static inline pid_t task_tgid_vnr(struct task_struct *tsk)
{
	return pid_vnr(task_tgid(tsk));
}


1840
static inline int pid_alive(const struct task_struct *p);
1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857
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);
}

1858 1859
static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
					struct pid_namespace *ns)
1860
{
1861
	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1862 1863 1864 1865
}

static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
{
1866
	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1867 1868 1869
}


1870 1871
static inline pid_t task_session_nr_ns(struct task_struct *tsk,
					struct pid_namespace *ns)
1872
{
1873
	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1874 1875 1876 1877
}

static inline pid_t task_session_vnr(struct task_struct *tsk)
{
1878
	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1879 1880
}

1881 1882 1883 1884 1885
/* obsolete, do not use */
static inline pid_t task_pgrp_nr(struct task_struct *tsk)
{
	return task_pgrp_nr_ns(tsk, &init_pid_ns);
}
1886

L
Linus Torvalds 已提交
1887 1888 1889 1890 1891 1892 1893
/**
 * 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.
1894 1895
 *
 * Return: 1 if the process is alive. 0 otherwise.
L
Linus Torvalds 已提交
1896
 */
1897
static inline int pid_alive(const struct task_struct *p)
L
Linus Torvalds 已提交
1898
{
1899
	return p->pids[PIDTYPE_PID].pid != NULL;
L
Linus Torvalds 已提交
1900 1901
}

1902
/**
1903
 * is_global_init - check if a task structure is init
1904 1905 1906
 * @tsk: Task structure to be checked.
 *
 * Check if a task structure is the first user space task the kernel created.
1907 1908
 *
 * Return: 1 if the task structure is init. 0 otherwise.
1909
 */
A
Alexey Dobriyan 已提交
1910
static inline int is_global_init(struct task_struct *tsk)
1911 1912 1913
{
	return tsk->pid == 1;
}
1914

1915 1916
extern struct pid *cad_pid;

L
Linus Torvalds 已提交
1917 1918
extern void free_task(struct task_struct *tsk);
#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
I
Ingo Molnar 已提交
1919

1920
extern void __put_task_struct(struct task_struct *t);
I
Ingo Molnar 已提交
1921 1922 1923 1924

static inline void put_task_struct(struct task_struct *t)
{
	if (atomic_dec_and_test(&t->usage))
1925
		__put_task_struct(t);
I
Ingo Molnar 已提交
1926
}
L
Linus Torvalds 已提交
1927

1928 1929 1930 1931 1932 1933 1934
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
extern void task_cputime(struct task_struct *t,
			 cputime_t *utime, cputime_t *stime);
extern void task_cputime_scaled(struct task_struct *t,
				cputime_t *utimescaled, cputime_t *stimescaled);
extern cputime_t task_gtime(struct task_struct *t);
#else
1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952
static inline void task_cputime(struct task_struct *t,
				cputime_t *utime, cputime_t *stime)
{
	if (utime)
		*utime = t->utime;
	if (stime)
		*stime = t->stime;
}

static inline void task_cputime_scaled(struct task_struct *t,
				       cputime_t *utimescaled,
				       cputime_t *stimescaled)
{
	if (utimescaled)
		*utimescaled = t->utimescaled;
	if (stimescaled)
		*stimescaled = t->stimescaled;
}
1953 1954 1955 1956 1957 1958

static inline cputime_t task_gtime(struct task_struct *t)
{
	return t->gtime;
}
#endif
1959 1960
extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
1961

L
Linus Torvalds 已提交
1962 1963 1964 1965
/*
 * Per process flags
 */
#define PF_EXITING	0x00000004	/* getting shut down */
1966
#define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
1967
#define PF_VCPU		0x00000010	/* I'm a virtual CPU */
T
Tejun Heo 已提交
1968
#define PF_WQ_WORKER	0x00000020	/* I'm a workqueue worker */
L
Linus Torvalds 已提交
1969
#define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
1970
#define PF_MCE_PROCESS  0x00000080      /* process policy on mce errors */
L
Linus Torvalds 已提交
1971 1972 1973 1974
#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 */
1975
#define PF_NPROC_EXCEEDED 0x00001000	/* set_user noticed that RLIMIT_NPROC was exceeded */
L
Linus Torvalds 已提交
1976
#define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
1977
#define PF_USED_ASYNC	0x00004000	/* used async_schedule*(), used by module init */
L
Linus Torvalds 已提交
1978 1979 1980 1981
#define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
#define PF_FROZEN	0x00010000	/* frozen for system suspend */
#define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
#define PF_KSWAPD	0x00040000	/* I am kswapd */
1982
#define PF_MEMALLOC_NOIO 0x00080000	/* Allocating memory without IO involved */
L
Linus Torvalds 已提交
1983
#define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
1984
#define PF_KTHREAD	0x00200000	/* I am a kernel thread */
J
Jens Axboe 已提交
1985 1986
#define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
#define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
1987
#define PF_NO_SETAFFINITY 0x04000000	/* Userland is not allowed to meddle with cpus_allowed */
1988
#define PF_MCE_EARLY    0x08000000      /* Early kill for mce process policy */
1989
#define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
1990
#define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezable */
1991
#define PF_SUSPEND_TASK 0x80000000      /* this thread called freeze_processes and should not be frozen */
L
Linus Torvalds 已提交
1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017

/*
 * 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.
 */
#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)
#define conditional_stopped_child_used_math(condition, child) \
	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
#define conditional_used_math(condition) \
	conditional_stopped_child_used_math(condition, current)
#define copy_to_stopped_child_used_math(child) \
	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
#define used_math() tsk_used_math(current)

2018 2019 2020
/* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags
 * __GFP_FS is also cleared as it implies __GFP_IO.
 */
2021 2022 2023
static inline gfp_t memalloc_noio_flags(gfp_t flags)
{
	if (unlikely(current->flags & PF_MEMALLOC_NOIO))
2024
		flags &= ~(__GFP_IO | __GFP_FS);
2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039
	return flags;
}

static inline unsigned int memalloc_noio_save(void)
{
	unsigned int flags = current->flags & PF_MEMALLOC_NOIO;
	current->flags |= PF_MEMALLOC_NOIO;
	return flags;
}

static inline void memalloc_noio_restore(unsigned int flags)
{
	current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags;
}

2040
/* Per-process atomic flags. */
2041
#define PFA_NO_NEW_PRIVS 0	/* May not gain new privileges. */
2042 2043 2044
#define PFA_SPREAD_PAGE  1      /* Spread page cache over cpuset */
#define PFA_SPREAD_SLAB  2      /* Spread some slab caches over cpuset */

2045

2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057
#define TASK_PFA_TEST(name, func)					\
	static inline bool task_##func(struct task_struct *p)		\
	{ return test_bit(PFA_##name, &p->atomic_flags); }
#define TASK_PFA_SET(name, func)					\
	static inline void task_set_##func(struct task_struct *p)	\
	{ set_bit(PFA_##name, &p->atomic_flags); }
#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)
2058

2059 2060 2061 2062 2063 2064 2065
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)
2066

2067
/*
2068
 * task->jobctl flags
2069
 */
2070
#define JOBCTL_STOP_SIGMASK	0xffff	/* signr of the last group stop */
2071

2072 2073 2074
#define JOBCTL_STOP_DEQUEUED_BIT 16	/* stop signal dequeued */
#define JOBCTL_STOP_PENDING_BIT	17	/* task should stop for group stop */
#define JOBCTL_STOP_CONSUME_BIT	18	/* consume group stop count */
2075
#define JOBCTL_TRAP_STOP_BIT	19	/* trap for STOP */
2076
#define JOBCTL_TRAP_NOTIFY_BIT	20	/* trap for NOTIFY */
2077
#define JOBCTL_TRAPPING_BIT	21	/* switching to TRACED */
T
Tejun Heo 已提交
2078
#define JOBCTL_LISTENING_BIT	22	/* ptracer is listening for events */
2079 2080 2081 2082

#define JOBCTL_STOP_DEQUEUED	(1 << JOBCTL_STOP_DEQUEUED_BIT)
#define JOBCTL_STOP_PENDING	(1 << JOBCTL_STOP_PENDING_BIT)
#define JOBCTL_STOP_CONSUME	(1 << JOBCTL_STOP_CONSUME_BIT)
2083
#define JOBCTL_TRAP_STOP	(1 << JOBCTL_TRAP_STOP_BIT)
2084
#define JOBCTL_TRAP_NOTIFY	(1 << JOBCTL_TRAP_NOTIFY_BIT)
2085
#define JOBCTL_TRAPPING		(1 << JOBCTL_TRAPPING_BIT)
T
Tejun Heo 已提交
2086
#define JOBCTL_LISTENING	(1 << JOBCTL_LISTENING_BIT)
2087

2088
#define JOBCTL_TRAP_MASK	(JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY)
2089
#define JOBCTL_PENDING_MASK	(JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK)
2090

2091 2092
extern bool task_set_jobctl_pending(struct task_struct *task,
				    unsigned int mask);
2093
extern void task_clear_jobctl_trapping(struct task_struct *task);
2094 2095
extern void task_clear_jobctl_pending(struct task_struct *task,
				      unsigned int mask);
2096

2097 2098
static inline void rcu_copy_process(struct task_struct *p)
{
P
Paul E. McKenney 已提交
2099
#ifdef CONFIG_PREEMPT_RCU
2100
	p->rcu_read_lock_nesting = 0;
2101
	p->rcu_read_unlock_special.s = 0;
2102
	p->rcu_blocked_node = NULL;
2103
	INIT_LIST_HEAD(&p->rcu_node_entry);
P
Paul E. McKenney 已提交
2104 2105 2106 2107
#endif /* #ifdef CONFIG_PREEMPT_RCU */
#ifdef CONFIG_TASKS_RCU
	p->rcu_tasks_holdout = false;
	INIT_LIST_HEAD(&p->rcu_tasks_holdout_list);
2108
	p->rcu_tasks_idle_cpu = -1;
P
Paul E. McKenney 已提交
2109
#endif /* #ifdef CONFIG_TASKS_RCU */
2110 2111
}

2112 2113 2114 2115 2116 2117 2118
static inline void tsk_restore_flags(struct task_struct *task,
				unsigned long orig_flags, unsigned long flags)
{
	task->flags &= ~flags;
	task->flags |= orig_flags & flags;
}

2119 2120
extern int cpuset_cpumask_can_shrink(const struct cpumask *cur,
				     const struct cpumask *trial);
2121 2122
extern int task_can_attach(struct task_struct *p,
			   const struct cpumask *cs_cpus_allowed);
L
Linus Torvalds 已提交
2123
#ifdef CONFIG_SMP
2124 2125 2126
extern void do_set_cpus_allowed(struct task_struct *p,
			       const struct cpumask *new_mask);

2127
extern int set_cpus_allowed_ptr(struct task_struct *p,
2128
				const struct cpumask *new_mask);
L
Linus Torvalds 已提交
2129
#else
2130 2131 2132 2133
static inline void do_set_cpus_allowed(struct task_struct *p,
				      const struct cpumask *new_mask)
{
}
2134
static inline int set_cpus_allowed_ptr(struct task_struct *p,
2135
				       const struct cpumask *new_mask)
L
Linus Torvalds 已提交
2136
{
2137
	if (!cpumask_test_cpu(0, new_mask))
L
Linus Torvalds 已提交
2138 2139 2140 2141
		return -EINVAL;
	return 0;
}
#endif
2142

2143
#ifdef CONFIG_NO_HZ_COMMON
2144 2145 2146 2147 2148
void calc_load_enter_idle(void);
void calc_load_exit_idle(void);
#else
static inline void calc_load_enter_idle(void) { }
static inline void calc_load_exit_idle(void) { }
2149
#endif /* CONFIG_NO_HZ_COMMON */
2150

2151
#ifndef CONFIG_CPUMASK_OFFSTACK
2152 2153 2154 2155
static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
{
	return set_cpus_allowed_ptr(p, &new_mask);
}
2156
#endif
L
Linus Torvalds 已提交
2157

2158
/*
2159 2160 2161 2162 2163 2164
 * Do not use outside of architecture code which knows its limitations.
 *
 * sched_clock() has no promise of monotonicity or bounded drift between
 * CPUs, use (which you should not) requires disabling IRQs.
 *
 * Please use one of the three interfaces below.
2165
 */
2166
extern unsigned long long notrace sched_clock(void);
2167
/*
2168
 * See the comment in kernel/sched/clock.c
2169 2170 2171
 */
extern u64 cpu_clock(int cpu);
extern u64 local_clock(void);
2172
extern u64 running_clock(void);
2173 2174
extern u64 sched_clock_cpu(int cpu);

2175

2176
extern void sched_clock_init(void);
2177

2178
#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190
static inline void sched_clock_tick(void)
{
}

static inline void sched_clock_idle_sleep_event(void)
{
}

static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
{
}
#else
2191 2192 2193 2194 2195 2196
/*
 * Architectures can set this to 1 if they have specified
 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
 * but then during bootup it turns out that sched_clock()
 * is reliable after all:
 */
2197 2198 2199
extern int sched_clock_stable(void);
extern void set_sched_clock_stable(void);
extern void clear_sched_clock_stable(void);
2200

2201 2202 2203 2204 2205
extern void sched_clock_tick(void);
extern void sched_clock_idle_sleep_event(void);
extern void sched_clock_idle_wakeup_event(u64 delta_ns);
#endif

2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218
#ifdef CONFIG_IRQ_TIME_ACCOUNTING
/*
 * An i/f to runtime opt-in for irq time accounting based off of sched_clock.
 * The reason for this explicit opt-in is not to have perf penalty with
 * slow sched_clocks.
 */
extern void enable_sched_clock_irqtime(void);
extern void disable_sched_clock_irqtime(void);
#else
static inline void enable_sched_clock_irqtime(void) {}
static inline void disable_sched_clock_irqtime(void) {}
#endif

2219
extern unsigned long long
2220
task_sched_runtime(struct task_struct *task);
L
Linus Torvalds 已提交
2221 2222 2223 2224 2225 2226 2227 2228

/* sched_exec is called by processes performing an exec */
#ifdef CONFIG_SMP
extern void sched_exec(void);
#else
#define sched_exec()   {}
#endif

2229 2230
extern void sched_clock_idle_sleep_event(void);
extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2231

L
Linus Torvalds 已提交
2232 2233 2234 2235 2236 2237
#ifdef CONFIG_HOTPLUG_CPU
extern void idle_task_exit(void);
#else
static inline void idle_task_exit(void) {}
#endif

2238
#if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP)
2239
extern void wake_up_nohz_cpu(int cpu);
2240
#else
2241
static inline void wake_up_nohz_cpu(int cpu) { }
2242 2243
#endif

2244 2245
#ifdef CONFIG_NO_HZ_FULL
extern bool sched_can_stop_tick(void);
2246
extern u64 scheduler_tick_max_deferment(void);
2247 2248
#else
static inline bool sched_can_stop_tick(void) { return false; }
2249 2250
#endif

2251 2252 2253 2254 2255 2256 2257
#ifdef CONFIG_SCHED_AUTOGROUP
extern void sched_autogroup_create_attach(struct task_struct *p);
extern void sched_autogroup_detach(struct task_struct *p);
extern void sched_autogroup_fork(struct signal_struct *sig);
extern void sched_autogroup_exit(struct signal_struct *sig);
#ifdef CONFIG_PROC_FS
extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
2258
extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice);
2259 2260 2261 2262 2263 2264 2265 2266
#endif
#else
static inline void sched_autogroup_create_attach(struct task_struct *p) { }
static inline void sched_autogroup_detach(struct task_struct *p) { }
static inline void sched_autogroup_fork(struct signal_struct *sig) { }
static inline void sched_autogroup_exit(struct signal_struct *sig) { }
#endif

2267
extern int yield_to(struct task_struct *p, bool preempt);
2268 2269
extern void set_user_nice(struct task_struct *p, long nice);
extern int task_prio(const struct task_struct *p);
2270 2271 2272 2273 2274 2275 2276 2277 2278 2279
/**
 * 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);
}
2280 2281
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
2282
extern int idle_cpu(int cpu);
2283 2284
extern int sched_setscheduler(struct task_struct *, int,
			      const struct sched_param *);
2285
extern int sched_setscheduler_nocheck(struct task_struct *, int,
2286
				      const struct sched_param *);
2287 2288
extern int sched_setattr(struct task_struct *,
			 const struct sched_attr *);
2289
extern struct task_struct *idle_task(int cpu);
2290 2291
/**
 * is_idle_task - is the specified task an idle task?
2292
 * @p: the task in question.
2293 2294
 *
 * Return: 1 if @p is an idle task. 0 otherwise.
2295
 */
2296
static inline bool is_idle_task(const struct task_struct *p)
2297 2298 2299
{
	return p->pid == 0;
}
2300 2301
extern struct task_struct *curr_task(int cpu);
extern void set_curr_task(int cpu, struct task_struct *p);
L
Linus Torvalds 已提交
2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324

void yield(void);

union thread_union {
	struct thread_info thread_info;
	unsigned long stack[THREAD_SIZE/sizeof(long)];
};

#ifndef __HAVE_ARCH_KSTACK_END
static inline int kstack_end(void *addr)
{
	/* Reliable end of stack detection:
	 * Some APM bios versions misalign the stack
	 */
	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
}
#endif

extern union thread_union init_thread_union;
extern struct task_struct init_task;

extern struct   mm_struct init_mm;

2325 2326 2327 2328 2329 2330 2331
extern struct pid_namespace init_pid_ns;

/*
 * find a task by one of its numerical ids
 *
 * find_task_by_pid_ns():
 *      finds a task by its pid in the specified namespace
2332 2333
 * find_task_by_vpid():
 *      finds a task by its virtual pid
2334
 *
2335
 * see also find_vpid() etc in include/linux/pid.h
2336 2337
 */

2338 2339 2340
extern struct task_struct *find_task_by_vpid(pid_t nr);
extern struct task_struct *find_task_by_pid_ns(pid_t nr,
		struct pid_namespace *ns);
2341

L
Linus Torvalds 已提交
2342
/* per-UID process charging. */
2343
extern struct user_struct * alloc_uid(kuid_t);
L
Linus Torvalds 已提交
2344 2345 2346 2347 2348 2349 2350 2351 2352
static inline struct user_struct *get_uid(struct user_struct *u)
{
	atomic_inc(&u->__count);
	return u;
}
extern void free_uid(struct user_struct *);

#include <asm/current.h>

T
Torben Hohn 已提交
2353
extern void xtime_update(unsigned long ticks);
L
Linus Torvalds 已提交
2354

2355 2356
extern int wake_up_state(struct task_struct *tsk, unsigned int state);
extern int wake_up_process(struct task_struct *tsk);
2357
extern void wake_up_new_task(struct task_struct *tsk);
L
Linus Torvalds 已提交
2358 2359 2360 2361 2362
#ifdef CONFIG_SMP
 extern void kick_process(struct task_struct *tsk);
#else
 static inline void kick_process(struct task_struct *tsk) { }
#endif
2363
extern int sched_fork(unsigned long clone_flags, struct task_struct *p);
2364
extern void sched_dead(struct task_struct *p);
L
Linus Torvalds 已提交
2365 2366 2367

extern void proc_caches_init(void);
extern void flush_signals(struct task_struct *);
2368
extern void __flush_signals(struct task_struct *);
2369
extern void ignore_signals(struct task_struct *);
L
Linus Torvalds 已提交
2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382
extern void flush_signal_handlers(struct task_struct *, int force_default);
extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);

static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
{
	unsigned long flags;
	int ret;

	spin_lock_irqsave(&tsk->sighand->siglock, flags);
	ret = dequeue_signal(tsk, mask, info);
	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);

	return ret;
2383
}
L
Linus Torvalds 已提交
2384 2385 2386 2387 2388 2389 2390 2391

extern void block_all_signals(int (*notifier)(void *priv), void *priv,
			      sigset_t *mask);
extern void unblock_all_signals(void);
extern void release_task(struct task_struct * p);
extern int send_sig_info(int, struct siginfo *, struct task_struct *);
extern int force_sigsegv(int, struct task_struct *);
extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2392 2393
extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2394 2395
extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *,
				const struct cred *, u32);
2396 2397
extern int kill_pgrp(struct pid *pid, int sig, int priv);
extern int kill_pid(struct pid *pid, int sig, int priv);
2398
extern int kill_proc_info(int, struct siginfo *, pid_t);
2399
extern __must_check bool do_notify_parent(struct task_struct *, int);
2400
extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
L
Linus Torvalds 已提交
2401 2402
extern void force_sig(int, struct task_struct *);
extern int send_sig(int, struct task_struct *, int);
2403
extern int zap_other_threads(struct task_struct *p);
L
Linus Torvalds 已提交
2404 2405
extern struct sigqueue *sigqueue_alloc(void);
extern void sigqueue_free(struct sigqueue *);
2406
extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
2407
extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
L
Linus Torvalds 已提交
2408

A
Al Viro 已提交
2409 2410 2411
static inline void restore_saved_sigmask(void)
{
	if (test_and_clear_restore_sigmask())
2412
		__set_current_blocked(&current->saved_sigmask);
A
Al Viro 已提交
2413 2414
}

A
Al Viro 已提交
2415 2416 2417 2418 2419 2420 2421 2422
static inline sigset_t *sigmask_to_save(void)
{
	sigset_t *res = &current->blocked;
	if (unlikely(test_restore_sigmask()))
		res = &current->saved_sigmask;
	return res;
}

2423 2424 2425 2426 2427
static inline int kill_cad_pid(int sig, int priv)
{
	return kill_pid(cad_pid, sig, priv);
}

L
Linus Torvalds 已提交
2428 2429 2430 2431 2432
/* These can be the second arg to send_sig_info/send_group_sig_info.  */
#define SEND_SIG_NOINFO ((struct siginfo *) 0)
#define SEND_SIG_PRIV	((struct siginfo *) 1)
#define SEND_SIG_FORCED	((struct siginfo *) 2)

2433 2434 2435
/*
 * True if we are on the alternate signal stack.
 */
L
Linus Torvalds 已提交
2436 2437
static inline int on_sig_stack(unsigned long sp)
{
2438 2439 2440 2441 2442 2443 2444
#ifdef CONFIG_STACK_GROWSUP
	return sp >= current->sas_ss_sp &&
		sp - current->sas_ss_sp < current->sas_ss_size;
#else
	return sp > current->sas_ss_sp &&
		sp - current->sas_ss_sp <= current->sas_ss_size;
#endif
L
Linus Torvalds 已提交
2445 2446 2447 2448
}

static inline int sas_ss_flags(unsigned long sp)
{
2449 2450 2451 2452
	if (!current->sas_ss_size)
		return SS_DISABLE;

	return on_sig_stack(sp) ? SS_ONSTACK : 0;
L
Linus Torvalds 已提交
2453 2454
}

A
Al Viro 已提交
2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465
static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig)
{
	if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp))
#ifdef CONFIG_STACK_GROWSUP
		return current->sas_ss_sp;
#else
		return current->sas_ss_sp + current->sas_ss_size;
#endif
	return sp;
}

L
Linus Torvalds 已提交
2466 2467 2468 2469 2470 2471
/*
 * Routines for handling mm_structs
 */
extern struct mm_struct * mm_alloc(void);

/* mmdrop drops the mm and the page tables */
2472
extern void __mmdrop(struct mm_struct *);
L
Linus Torvalds 已提交
2473 2474
static inline void mmdrop(struct mm_struct * mm)
{
I
Ingo Molnar 已提交
2475
	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
L
Linus Torvalds 已提交
2476 2477 2478 2479 2480 2481 2482
		__mmdrop(mm);
}

/* mmput gets rid of the mappings and all user-space */
extern void mmput(struct mm_struct *);
/* Grab a reference to a task's mm, if it is not already going away */
extern struct mm_struct *get_task_mm(struct task_struct *task);
2483 2484 2485 2486 2487 2488
/*
 * Grab a reference to a task's mm, if it is not already going away
 * and ptrace_may_access with the mode parameter passed to it
 * succeeds.
 */
extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode);
L
Linus Torvalds 已提交
2489 2490 2491
/* Remove the current tasks stale references to the old mm_struct */
extern void mm_release(struct task_struct *, struct mm_struct *);

A
Alexey Dobriyan 已提交
2492
extern int copy_thread(unsigned long, unsigned long, unsigned long,
2493
			struct task_struct *);
L
Linus Torvalds 已提交
2494 2495 2496 2497
extern void flush_thread(void);
extern void exit_thread(void);

extern void exit_files(struct task_struct *);
2498
extern void __cleanup_sighand(struct sighand_struct *);
2499

L
Linus Torvalds 已提交
2500
extern void exit_itimers(struct signal_struct *);
2501
extern void flush_itimer_signals(void);
L
Linus Torvalds 已提交
2502

2503
extern void do_group_exit(int);
L
Linus Torvalds 已提交
2504

2505
extern int do_execve(struct filename *,
2506
		     const char __user * const __user *,
2507
		     const char __user * const __user *);
2508 2509 2510 2511
extern int do_execveat(int, struct filename *,
		       const char __user * const __user *,
		       const char __user * const __user *,
		       int);
2512
extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *);
2513
struct task_struct *fork_idle(int);
2514
extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
L
Linus Torvalds 已提交
2515

2516 2517 2518 2519 2520
extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
static inline void set_task_comm(struct task_struct *tsk, const char *from)
{
	__set_task_comm(tsk, from, false);
}
2521
extern char *get_task_comm(char *to, struct task_struct *tsk);
L
Linus Torvalds 已提交
2522 2523

#ifdef CONFIG_SMP
2524
void scheduler_ipi(void);
R
Roland McGrath 已提交
2525
extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
L
Linus Torvalds 已提交
2526
#else
2527
static inline void scheduler_ipi(void) { }
R
Roland McGrath 已提交
2528 2529 2530 2531 2532
static inline unsigned long wait_task_inactive(struct task_struct *p,
					       long match_state)
{
	return 1;
}
L
Linus Torvalds 已提交
2533 2534
#endif

2535 2536
#define next_task(p) \
	list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
L
Linus Torvalds 已提交
2537 2538 2539 2540

#define for_each_process(p) \
	for (p = &init_task ; (p = next_task(p)) != &init_task ; )

2541
extern bool current_is_single_threaded(void);
D
David Howells 已提交
2542

L
Linus Torvalds 已提交
2543 2544 2545 2546 2547 2548 2549 2550 2551 2552
/*
 * Careful: do_each_thread/while_each_thread is a double loop so
 *          'break' will not work as expected - use goto instead.
 */
#define do_each_thread(g, t) \
	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do

#define while_each_thread(g, t) \
	while ((t = next_thread(t)) != g)

2553 2554 2555 2556 2557 2558 2559 2560 2561 2562
#define __for_each_thread(signal, t)	\
	list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node)

#define for_each_thread(p, t)		\
	__for_each_thread((p)->signal, t)

/* Careful: this is a double loop, 'break' won't work as expected. */
#define for_each_process_thread(p, t)	\
	for_each_process(p) for_each_thread(p, t)

2563 2564
static inline int get_nr_threads(struct task_struct *tsk)
{
2565
	return tsk->signal->nr_threads;
2566 2567
}

2568 2569 2570 2571
static inline bool thread_group_leader(struct task_struct *p)
{
	return p->exit_signal >= 0;
}
L
Linus Torvalds 已提交
2572

2573 2574 2575 2576 2577 2578
/* Do to the insanities of de_thread it is possible for a process
 * to have the pid of the thread group leader without actually being
 * the thread group leader.  For iteration through the pids in proc
 * all we care about is that we have a task with the appropriate
 * pid, we don't actually care if we have the right task.
 */
2579
static inline bool has_group_leader_pid(struct task_struct *p)
2580
{
2581
	return task_pid(p) == p->signal->leader_pid;
2582 2583
}

2584
static inline
2585
bool same_thread_group(struct task_struct *p1, struct task_struct *p2)
2586
{
2587
	return p1->signal == p2->signal;
2588 2589
}

2590
static inline struct task_struct *next_thread(const struct task_struct *p)
O
Oleg Nesterov 已提交
2591
{
2592 2593
	return list_entry_rcu(p->thread_group.next,
			      struct task_struct, thread_group);
O
Oleg Nesterov 已提交
2594 2595
}

A
Alexey Dobriyan 已提交
2596
static inline int thread_group_empty(struct task_struct *p)
L
Linus Torvalds 已提交
2597
{
O
Oleg Nesterov 已提交
2598
	return list_empty(&p->thread_group);
L
Linus Torvalds 已提交
2599 2600 2601 2602 2603 2604
}

#define delay_group_leader(p) \
		(thread_group_leader(p) && !thread_group_empty(p))

/*
2605
 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2606
 * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2607
 * pins the final release of task.io_context.  Also protects ->cpuset and
O
Oleg Nesterov 已提交
2608
 * ->cgroup.subsys[]. And ->vfork_done.
L
Linus Torvalds 已提交
2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623
 *
 * Nests both inside and outside of read_lock(&tasklist_lock).
 * It must not be nested with write_lock_irq(&tasklist_lock),
 * neither inside nor outside.
 */
static inline void task_lock(struct task_struct *p)
{
	spin_lock(&p->alloc_lock);
}

static inline void task_unlock(struct task_struct *p)
{
	spin_unlock(&p->alloc_lock);
}

2624
extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
2625 2626
							unsigned long *flags);

2627 2628 2629 2630 2631 2632 2633 2634 2635
static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
						       unsigned long *flags)
{
	struct sighand_struct *ret;

	ret = __lock_task_sighand(tsk, flags);
	(void)__cond_lock(&tsk->sighand->siglock, ret);
	return ret;
}
2636

2637 2638 2639 2640 2641 2642
static inline void unlock_task_sighand(struct task_struct *tsk,
						unsigned long *flags)
{
	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
}

2643
#ifdef CONFIG_CGROUPS
2644
static inline void threadgroup_change_begin(struct task_struct *tsk)
2645
{
2646
	down_read(&tsk->signal->group_rwsem);
2647
}
2648
static inline void threadgroup_change_end(struct task_struct *tsk)
2649
{
2650
	up_read(&tsk->signal->group_rwsem);
2651
}
2652 2653 2654 2655 2656 2657 2658

/**
 * threadgroup_lock - lock threadgroup
 * @tsk: member task of the threadgroup to lock
 *
 * Lock the threadgroup @tsk belongs to.  No new task is allowed to enter
 * and member tasks aren't allowed to exit (as indicated by PF_EXITING) or
2659 2660
 * change ->group_leader/pid.  This is useful for cases where the threadgroup
 * needs to stay stable across blockable operations.
2661 2662 2663 2664 2665
 *
 * fork and exit paths explicitly call threadgroup_change_{begin|end}() for
 * synchronization.  While held, no new task will be added to threadgroup
 * and no existing live task will have its PF_EXITING set.
 *
2666 2667
 * de_thread() does threadgroup_change_{begin|end}() when a non-leader
 * sub-thread becomes a new leader.
2668
 */
2669
static inline void threadgroup_lock(struct task_struct *tsk)
2670
{
2671
	down_write(&tsk->signal->group_rwsem);
2672
}
2673 2674 2675 2676 2677 2678 2679

/**
 * threadgroup_unlock - unlock threadgroup
 * @tsk: member task of the threadgroup to unlock
 *
 * Reverse threadgroup_lock().
 */
2680
static inline void threadgroup_unlock(struct task_struct *tsk)
2681
{
2682
	up_write(&tsk->signal->group_rwsem);
2683 2684
}
#else
2685 2686 2687 2688
static inline void threadgroup_change_begin(struct task_struct *tsk) {}
static inline void threadgroup_change_end(struct task_struct *tsk) {}
static inline void threadgroup_lock(struct task_struct *tsk) {}
static inline void threadgroup_unlock(struct task_struct *tsk) {}
2689 2690
#endif

A
Al Viro 已提交
2691 2692
#ifndef __HAVE_THREAD_FUNCTIONS

R
Roman Zippel 已提交
2693 2694
#define task_thread_info(task)	((struct thread_info *)(task)->stack)
#define task_stack_page(task)	((task)->stack)
A
Al Viro 已提交
2695

2696 2697 2698 2699 2700 2701
static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
{
	*task_thread_info(p) = *task_thread_info(org);
	task_thread_info(p)->task = p;
}

2702 2703 2704 2705 2706 2707 2708 2709 2710
/*
 * Return the address of the last usable long on the stack.
 *
 * When the stack grows down, this is just above the thread
 * info struct. Going any lower will corrupt the threadinfo.
 *
 * When the stack grows up, this is the highest address.
 * Beyond that position, we corrupt data on the next page.
 */
2711 2712
static inline unsigned long *end_of_stack(struct task_struct *p)
{
2713 2714 2715
#ifdef CONFIG_STACK_GROWSUP
	return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1;
#else
R
Roman Zippel 已提交
2716
	return (unsigned long *)(task_thread_info(p) + 1);
2717
#endif
2718 2719
}

A
Al Viro 已提交
2720
#endif
2721 2722
#define task_stack_end_corrupted(task) \
		(*(end_of_stack(task)) != STACK_END_MAGIC)
A
Al Viro 已提交
2723

2724 2725 2726 2727 2728 2729 2730
static inline int object_is_on_stack(void *obj)
{
	void *stack = task_stack_page(current);

	return (obj >= stack) && (obj < (stack + THREAD_SIZE));
}

2731 2732
extern void thread_info_cache_init(void);

2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744
#ifdef CONFIG_DEBUG_STACK_USAGE
static inline unsigned long stack_not_used(struct task_struct *p)
{
	unsigned long *n = end_of_stack(p);

	do { 	/* Skip over canary */
		n++;
	} while (!*n);

	return (unsigned long)n - (unsigned long)end_of_stack(p);
}
#endif
2745
extern void set_task_stack_end_magic(struct task_struct *tsk);
2746

L
Linus Torvalds 已提交
2747 2748 2749 2750 2751
/* set thread flags in other task's structures
 * - see asm/thread_info.h for TIF_xxxx flags available
 */
static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
{
A
Al Viro 已提交
2752
	set_ti_thread_flag(task_thread_info(tsk), flag);
L
Linus Torvalds 已提交
2753 2754 2755 2756
}

static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
{
A
Al Viro 已提交
2757
	clear_ti_thread_flag(task_thread_info(tsk), flag);
L
Linus Torvalds 已提交
2758 2759 2760 2761
}

static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
{
A
Al Viro 已提交
2762
	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
L
Linus Torvalds 已提交
2763 2764 2765 2766
}

static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
{
A
Al Viro 已提交
2767
	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
L
Linus Torvalds 已提交
2768 2769 2770 2771
}

static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
{
A
Al Viro 已提交
2772
	return test_ti_thread_flag(task_thread_info(tsk), flag);
L
Linus Torvalds 已提交
2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784
}

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);
}

2785 2786 2787 2788 2789
static inline int test_tsk_need_resched(struct task_struct *tsk)
{
	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
}

2790 2791 2792 2793 2794 2795
static inline int restart_syscall(void)
{
	set_tsk_thread_flag(current, TIF_SIGPENDING);
	return -ERESTARTNOINTR;
}

L
Linus Torvalds 已提交
2796 2797 2798 2799
static inline int signal_pending(struct task_struct *p)
{
	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
}
M
Matthew Wilcox 已提交
2800

2801 2802 2803 2804
static inline int __fatal_signal_pending(struct task_struct *p)
{
	return unlikely(sigismember(&p->pending.signal, SIGKILL));
}
M
Matthew Wilcox 已提交
2805 2806 2807 2808 2809 2810

static inline int fatal_signal_pending(struct task_struct *p)
{
	return signal_pending(p) && __fatal_signal_pending(p);
}

2811 2812 2813 2814 2815 2816 2817 2818 2819 2820
static inline int signal_pending_state(long state, struct task_struct *p)
{
	if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
		return 0;
	if (!signal_pending(p))
		return 0;

	return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
}

L
Linus Torvalds 已提交
2821 2822 2823 2824 2825 2826 2827
/*
 * 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,
 * cond_resched_softirq() will enable bhs before scheduling.
 */
2828
extern int _cond_resched(void);
2829

2830
#define cond_resched() ({			\
2831
	___might_sleep(__FILE__, __LINE__, 0);	\
2832 2833
	_cond_resched();			\
})
2834

2835 2836
extern int __cond_resched_lock(spinlock_t *lock);

2837
#ifdef CONFIG_PREEMPT_COUNT
2838
#define PREEMPT_LOCK_OFFSET	PREEMPT_OFFSET
2839
#else
2840
#define PREEMPT_LOCK_OFFSET	0
2841
#endif
2842

2843
#define cond_resched_lock(lock) ({				\
2844
	___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
2845 2846 2847 2848 2849
	__cond_resched_lock(lock);				\
})

extern int __cond_resched_softirq(void);

2850
#define cond_resched_softirq() ({					\
2851
	___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET);	\
2852
	__cond_resched_softirq();					\
2853
})
L
Linus Torvalds 已提交
2854

2855 2856 2857 2858 2859 2860 2861 2862 2863
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
2864 2865
/*
 * Does a critical section need to be broken due to another
N
Nick Piggin 已提交
2866 2867
 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
 * but a general need for low latency)
L
Linus Torvalds 已提交
2868
 */
N
Nick Piggin 已提交
2869
static inline int spin_needbreak(spinlock_t *lock)
L
Linus Torvalds 已提交
2870
{
N
Nick Piggin 已提交
2871 2872 2873
#ifdef CONFIG_PREEMPT
	return spin_is_contended(lock);
#else
L
Linus Torvalds 已提交
2874
	return 0;
N
Nick Piggin 已提交
2875
#endif
L
Linus Torvalds 已提交
2876 2877
}

2878 2879
/*
 * Idle thread specific functions to determine the need_resched
2880
 * polling state.
2881
 */
2882
#ifdef TIF_POLLING_NRFLAG
2883 2884 2885 2886
static inline int tsk_is_polling(struct task_struct *p)
{
	return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG);
}
2887 2888

static inline void __current_set_polling(void)
2889 2890 2891 2892
{
	set_thread_flag(TIF_POLLING_NRFLAG);
}

2893 2894 2895 2896 2897 2898
static inline bool __must_check current_set_polling_and_test(void)
{
	__current_set_polling();

	/*
	 * Polling state must be visible before we test NEED_RESCHED,
2899
	 * paired by resched_curr()
2900
	 */
2901
	smp_mb__after_atomic();
2902 2903 2904 2905 2906

	return unlikely(tif_need_resched());
}

static inline void __current_clr_polling(void)
2907 2908 2909
{
	clear_thread_flag(TIF_POLLING_NRFLAG);
}
2910 2911 2912 2913 2914 2915 2916

static inline bool __must_check current_clr_polling_and_test(void)
{
	__current_clr_polling();

	/*
	 * Polling state must be visible before we test NEED_RESCHED,
2917
	 * paired by resched_curr()
2918
	 */
2919
	smp_mb__after_atomic();
2920 2921 2922 2923

	return unlikely(tif_need_resched());
}

2924 2925
#else
static inline int tsk_is_polling(struct task_struct *p) { return 0; }
2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936
static inline void __current_set_polling(void) { }
static inline void __current_clr_polling(void) { }

static inline bool __must_check current_set_polling_and_test(void)
{
	return unlikely(tif_need_resched());
}
static inline bool __must_check current_clr_polling_and_test(void)
{
	return unlikely(tif_need_resched());
}
2937 2938
#endif

2939 2940 2941 2942 2943 2944 2945 2946 2947 2948
static inline void current_clr_polling(void)
{
	__current_clr_polling();

	/*
	 * Ensure we check TIF_NEED_RESCHED after we clear the polling bit.
	 * Once the bit is cleared, we'll get IPIs with every new
	 * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also
	 * fold.
	 */
2949
	smp_mb(); /* paired with resched_curr() */
2950 2951 2952 2953

	preempt_fold_need_resched();
}

2954 2955 2956 2957 2958
static __always_inline bool need_resched(void)
{
	return unlikely(tif_need_resched());
}

2959 2960 2961
/*
 * Thread group CPU time accounting.
 */
2962
void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2963
void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2964

2965
static inline void thread_group_cputime_init(struct signal_struct *sig)
2966
{
2967
	raw_spin_lock_init(&sig->cputimer.lock);
2968 2969
}

R
Roland McGrath 已提交
2970 2971 2972 2973 2974 2975 2976
/*
 * Reevaluate whether the task has signals pending delivery.
 * Wake the task if so.
 * This is required every time the blocked sigset_t changes.
 * callers must hold sighand->siglock.
 */
extern void recalc_sigpending_and_wake(struct task_struct *t);
L
Linus Torvalds 已提交
2977 2978
extern void recalc_sigpending(void);

2979 2980 2981 2982 2983 2984 2985 2986 2987 2988
extern void signal_wake_up_state(struct task_struct *t, unsigned int state);

static inline void signal_wake_up(struct task_struct *t, bool resume)
{
	signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0);
}
static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume)
{
	signal_wake_up_state(t, resume ? __TASK_TRACED : 0);
}
L
Linus Torvalds 已提交
2989 2990 2991 2992 2993 2994 2995 2996

/*
 * 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)
{
A
Al Viro 已提交
2997
	return task_thread_info(p)->cpu;
L
Linus Torvalds 已提交
2998 2999
}

I
Ingo Molnar 已提交
3000 3001 3002 3003 3004
static inline int task_node(const struct task_struct *p)
{
	return cpu_to_node(task_cpu(p));
}

I
Ingo Molnar 已提交
3005
extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
L
Linus Torvalds 已提交
3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019

#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 */

3020 3021
extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
3022

D
Dhaval Giani 已提交
3023
#ifdef CONFIG_CGROUP_SCHED
3024
extern struct task_group root_task_group;
P
Peter Zijlstra 已提交
3025
#endif /* CONFIG_CGROUP_SCHED */
3026

3027 3028 3029
extern int task_can_switch_user(struct user_struct *up,
					struct task_struct *tsk);

3030 3031 3032
#ifdef CONFIG_TASK_XACCT
static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
{
3033
	tsk->ioac.rchar += amt;
3034 3035 3036 3037
}

static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
{
3038
	tsk->ioac.wchar += amt;
3039 3040 3041 3042
}

static inline void inc_syscr(struct task_struct *tsk)
{
3043
	tsk->ioac.syscr++;
3044 3045 3046 3047
}

static inline void inc_syscw(struct task_struct *tsk)
{
3048
	tsk->ioac.syscw++;
3049 3050 3051 3052 3053 3054 3055 3056 3057 3058 3059 3060 3061 3062 3063 3064 3065 3066 3067
}
#else
static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
{
}

static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
{
}

static inline void inc_syscr(struct task_struct *tsk)
{
}

static inline void inc_syscw(struct task_struct *tsk)
{
}
#endif

D
Dave Hansen 已提交
3068 3069 3070 3071
#ifndef TASK_SIZE_OF
#define TASK_SIZE_OF(tsk)	TASK_SIZE
#endif

O
Oleg Nesterov 已提交
3072
#ifdef CONFIG_MEMCG
3073 3074 3075 3076 3077
extern void mm_update_next_owner(struct mm_struct *mm);
#else
static inline void mm_update_next_owner(struct mm_struct *mm)
{
}
O
Oleg Nesterov 已提交
3078
#endif /* CONFIG_MEMCG */
3079

3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101
static inline unsigned long task_rlimit(const struct task_struct *tsk,
		unsigned int limit)
{
	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur);
}

static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
		unsigned int limit)
{
	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max);
}

static inline unsigned long rlimit(unsigned int limit)
{
	return task_rlimit(current, limit);
}

static inline unsigned long rlimit_max(unsigned int limit)
{
	return task_rlimit_max(current, limit);
}

L
Linus Torvalds 已提交
3102
#endif