xref: /linux/include/linux/sched.h (revision f19900b2e608b604777a74d6d711bbf744657756)
1 #ifndef _LINUX_SCHED_H
2 #define _LINUX_SCHED_H
3 
4 /*
5  * cloning flags:
6  */
7 #define CSIGNAL		0x000000ff	/* signal mask to be sent at exit */
8 #define CLONE_VM	0x00000100	/* set if VM shared between processes */
9 #define CLONE_FS	0x00000200	/* set if fs info shared between processes */
10 #define CLONE_FILES	0x00000400	/* set if open files shared between processes */
11 #define CLONE_SIGHAND	0x00000800	/* set if signal handlers and blocked signals shared */
12 #define CLONE_PTRACE	0x00002000	/* set if we want to let tracing continue on the child too */
13 #define CLONE_VFORK	0x00004000	/* set if the parent wants the child to wake it up on mm_release */
14 #define CLONE_PARENT	0x00008000	/* set if we want to have the same parent as the cloner */
15 #define CLONE_THREAD	0x00010000	/* Same thread group? */
16 #define CLONE_NEWNS	0x00020000	/* New namespace group? */
17 #define CLONE_SYSVSEM	0x00040000	/* share system V SEM_UNDO semantics */
18 #define CLONE_SETTLS	0x00080000	/* create a new TLS for the child */
19 #define CLONE_PARENT_SETTID	0x00100000	/* set the TID in the parent */
20 #define CLONE_CHILD_CLEARTID	0x00200000	/* clear the TID in the child */
21 #define CLONE_DETACHED		0x00400000	/* Unused, ignored */
22 #define CLONE_UNTRACED		0x00800000	/* set if the tracing process can't force CLONE_PTRACE on this clone */
23 #define CLONE_CHILD_SETTID	0x01000000	/* set the TID in the child */
24 #define CLONE_STOPPED		0x02000000	/* Start in stopped state */
25 #define CLONE_NEWUTS		0x04000000	/* New utsname group? */
26 #define CLONE_NEWIPC		0x08000000	/* New ipcs */
27 #define CLONE_NEWUSER		0x10000000	/* New user namespace */
28 #define CLONE_NEWPID		0x20000000	/* New pid namespace */
29 #define CLONE_NEWNET		0x40000000	/* New network namespace */
30 #define CLONE_IO		0x80000000	/* Clone io context */
31 
32 /*
33  * Scheduling policies
34  */
35 #define SCHED_NORMAL		0
36 #define SCHED_FIFO		1
37 #define SCHED_RR		2
38 #define SCHED_BATCH		3
39 /* SCHED_ISO: reserved but not implemented yet */
40 #define SCHED_IDLE		5
41 
42 #ifdef __KERNEL__
43 
44 struct sched_param {
45 	int sched_priority;
46 };
47 
48 #include <asm/param.h>	/* for HZ */
49 
50 #include <linux/capability.h>
51 #include <linux/threads.h>
52 #include <linux/kernel.h>
53 #include <linux/types.h>
54 #include <linux/timex.h>
55 #include <linux/jiffies.h>
56 #include <linux/rbtree.h>
57 #include <linux/thread_info.h>
58 #include <linux/cpumask.h>
59 #include <linux/errno.h>
60 #include <linux/nodemask.h>
61 #include <linux/mm_types.h>
62 
63 #include <asm/system.h>
64 #include <asm/page.h>
65 #include <asm/ptrace.h>
66 #include <asm/cputime.h>
67 
68 #include <linux/smp.h>
69 #include <linux/sem.h>
70 #include <linux/signal.h>
71 #include <linux/path.h>
72 #include <linux/compiler.h>
73 #include <linux/completion.h>
74 #include <linux/pid.h>
75 #include <linux/percpu.h>
76 #include <linux/topology.h>
77 #include <linux/proportions.h>
78 #include <linux/seccomp.h>
79 #include <linux/rcupdate.h>
80 #include <linux/rtmutex.h>
81 
82 #include <linux/time.h>
83 #include <linux/param.h>
84 #include <linux/resource.h>
85 #include <linux/timer.h>
86 #include <linux/hrtimer.h>
87 #include <linux/task_io_accounting.h>
88 #include <linux/kobject.h>
89 #include <linux/latencytop.h>
90 #include <linux/cred.h>
91 
92 #include <asm/processor.h>
93 
94 struct mem_cgroup;
95 struct exec_domain;
96 struct futex_pi_state;
97 struct robust_list_head;
98 struct bio;
99 struct bts_tracer;
100 struct fs_struct;
101 
102 /*
103  * List of flags we want to share for kernel threads,
104  * if only because they are not used by them anyway.
105  */
106 #define CLONE_KERNEL	(CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
107 
108 /*
109  * These are the constant used to fake the fixed-point load-average
110  * counting. Some notes:
111  *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
112  *    a load-average precision of 10 bits integer + 11 bits fractional
113  *  - if you want to count load-averages more often, you need more
114  *    precision, or rounding will get you. With 2-second counting freq,
115  *    the EXP_n values would be 1981, 2034 and 2043 if still using only
116  *    11 bit fractions.
117  */
118 extern unsigned long avenrun[];		/* Load averages */
119 
120 #define FSHIFT		11		/* nr of bits of precision */
121 #define FIXED_1		(1<<FSHIFT)	/* 1.0 as fixed-point */
122 #define LOAD_FREQ	(5*HZ+1)	/* 5 sec intervals */
123 #define EXP_1		1884		/* 1/exp(5sec/1min) as fixed-point */
124 #define EXP_5		2014		/* 1/exp(5sec/5min) */
125 #define EXP_15		2037		/* 1/exp(5sec/15min) */
126 
127 #define CALC_LOAD(load,exp,n) \
128 	load *= exp; \
129 	load += n*(FIXED_1-exp); \
130 	load >>= FSHIFT;
131 
132 extern unsigned long total_forks;
133 extern int nr_threads;
134 DECLARE_PER_CPU(unsigned long, process_counts);
135 extern int nr_processes(void);
136 extern unsigned long nr_running(void);
137 extern unsigned long nr_uninterruptible(void);
138 extern unsigned long nr_active(void);
139 extern unsigned long nr_iowait(void);
140 
141 extern unsigned long get_parent_ip(unsigned long addr);
142 
143 struct seq_file;
144 struct cfs_rq;
145 struct task_group;
146 #ifdef CONFIG_SCHED_DEBUG
147 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
148 extern void proc_sched_set_task(struct task_struct *p);
149 extern void
150 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
151 #else
152 static inline void
153 proc_sched_show_task(struct task_struct *p, struct seq_file *m)
154 {
155 }
156 static inline void proc_sched_set_task(struct task_struct *p)
157 {
158 }
159 static inline void
160 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
161 {
162 }
163 #endif
164 
165 extern unsigned long long time_sync_thresh;
166 
167 /*
168  * Task state bitmask. NOTE! These bits are also
169  * encoded in fs/proc/array.c: get_task_state().
170  *
171  * We have two separate sets of flags: task->state
172  * is about runnability, while task->exit_state are
173  * about the task exiting. Confusing, but this way
174  * modifying one set can't modify the other one by
175  * mistake.
176  */
177 #define TASK_RUNNING		0
178 #define TASK_INTERRUPTIBLE	1
179 #define TASK_UNINTERRUPTIBLE	2
180 #define __TASK_STOPPED		4
181 #define __TASK_TRACED		8
182 /* in tsk->exit_state */
183 #define EXIT_ZOMBIE		16
184 #define EXIT_DEAD		32
185 /* in tsk->state again */
186 #define TASK_DEAD		64
187 #define TASK_WAKEKILL		128
188 
189 /* Convenience macros for the sake of set_task_state */
190 #define TASK_KILLABLE		(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
191 #define TASK_STOPPED		(TASK_WAKEKILL | __TASK_STOPPED)
192 #define TASK_TRACED		(TASK_WAKEKILL | __TASK_TRACED)
193 
194 /* Convenience macros for the sake of wake_up */
195 #define TASK_NORMAL		(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
196 #define TASK_ALL		(TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
197 
198 /* get_task_state() */
199 #define TASK_REPORT		(TASK_RUNNING | TASK_INTERRUPTIBLE | \
200 				 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
201 				 __TASK_TRACED)
202 
203 #define task_is_traced(task)	((task->state & __TASK_TRACED) != 0)
204 #define task_is_stopped(task)	((task->state & __TASK_STOPPED) != 0)
205 #define task_is_stopped_or_traced(task)	\
206 			((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
207 #define task_contributes_to_load(task)	\
208 				((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
209 				 (task->flags & PF_FROZEN) == 0)
210 
211 #define __set_task_state(tsk, state_value)		\
212 	do { (tsk)->state = (state_value); } while (0)
213 #define set_task_state(tsk, state_value)		\
214 	set_mb((tsk)->state, (state_value))
215 
216 /*
217  * set_current_state() includes a barrier so that the write of current->state
218  * is correctly serialised wrt the caller's subsequent test of whether to
219  * actually sleep:
220  *
221  *	set_current_state(TASK_UNINTERRUPTIBLE);
222  *	if (do_i_need_to_sleep())
223  *		schedule();
224  *
225  * If the caller does not need such serialisation then use __set_current_state()
226  */
227 #define __set_current_state(state_value)			\
228 	do { current->state = (state_value); } while (0)
229 #define set_current_state(state_value)		\
230 	set_mb(current->state, (state_value))
231 
232 /* Task command name length */
233 #define TASK_COMM_LEN 16
234 
235 #include <linux/spinlock.h>
236 
237 /*
238  * This serializes "schedule()" and also protects
239  * the run-queue from deletions/modifications (but
240  * _adding_ to the beginning of the run-queue has
241  * a separate lock).
242  */
243 extern rwlock_t tasklist_lock;
244 extern spinlock_t mmlist_lock;
245 
246 struct task_struct;
247 
248 extern void sched_init(void);
249 extern void sched_init_smp(void);
250 extern asmlinkage void schedule_tail(struct task_struct *prev);
251 extern void init_idle(struct task_struct *idle, int cpu);
252 extern void init_idle_bootup_task(struct task_struct *idle);
253 
254 extern int runqueue_is_locked(void);
255 extern void task_rq_unlock_wait(struct task_struct *p);
256 
257 extern cpumask_var_t nohz_cpu_mask;
258 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
259 extern int select_nohz_load_balancer(int cpu);
260 #else
261 static inline int select_nohz_load_balancer(int cpu)
262 {
263 	return 0;
264 }
265 #endif
266 
267 /*
268  * Only dump TASK_* tasks. (0 for all tasks)
269  */
270 extern void show_state_filter(unsigned long state_filter);
271 
272 static inline void show_state(void)
273 {
274 	show_state_filter(0);
275 }
276 
277 extern void show_regs(struct pt_regs *);
278 
279 /*
280  * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
281  * task), SP is the stack pointer of the first frame that should be shown in the back
282  * trace (or NULL if the entire call-chain of the task should be shown).
283  */
284 extern void show_stack(struct task_struct *task, unsigned long *sp);
285 
286 void io_schedule(void);
287 long io_schedule_timeout(long timeout);
288 
289 extern void cpu_init (void);
290 extern void trap_init(void);
291 extern void update_process_times(int user);
292 extern void scheduler_tick(void);
293 
294 extern void sched_show_task(struct task_struct *p);
295 
296 #ifdef CONFIG_DETECT_SOFTLOCKUP
297 extern void softlockup_tick(void);
298 extern void touch_softlockup_watchdog(void);
299 extern void touch_all_softlockup_watchdogs(void);
300 extern int proc_dosoftlockup_thresh(struct ctl_table *table, int write,
301 				    struct file *filp, void __user *buffer,
302 				    size_t *lenp, loff_t *ppos);
303 extern unsigned int  softlockup_panic;
304 extern int softlockup_thresh;
305 #else
306 static inline void softlockup_tick(void)
307 {
308 }
309 static inline void touch_softlockup_watchdog(void)
310 {
311 }
312 static inline void touch_all_softlockup_watchdogs(void)
313 {
314 }
315 #endif
316 
317 #ifdef CONFIG_DETECT_HUNG_TASK
318 extern unsigned int  sysctl_hung_task_panic;
319 extern unsigned long sysctl_hung_task_check_count;
320 extern unsigned long sysctl_hung_task_timeout_secs;
321 extern unsigned long sysctl_hung_task_warnings;
322 extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
323 					 struct file *filp, void __user *buffer,
324 					 size_t *lenp, loff_t *ppos);
325 #endif
326 
327 /* Attach to any functions which should be ignored in wchan output. */
328 #define __sched		__attribute__((__section__(".sched.text")))
329 
330 /* Linker adds these: start and end of __sched functions */
331 extern char __sched_text_start[], __sched_text_end[];
332 
333 /* Is this address in the __sched functions? */
334 extern int in_sched_functions(unsigned long addr);
335 
336 #define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
337 extern signed long schedule_timeout(signed long timeout);
338 extern signed long schedule_timeout_interruptible(signed long timeout);
339 extern signed long schedule_timeout_killable(signed long timeout);
340 extern signed long schedule_timeout_uninterruptible(signed long timeout);
341 asmlinkage void __schedule(void);
342 asmlinkage void schedule(void);
343 extern int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner);
344 
345 struct nsproxy;
346 struct user_namespace;
347 
348 /* Maximum number of active map areas.. This is a random (large) number */
349 #define DEFAULT_MAX_MAP_COUNT	65536
350 
351 extern int sysctl_max_map_count;
352 
353 #include <linux/aio.h>
354 
355 extern unsigned long
356 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
357 		       unsigned long, unsigned long);
358 extern unsigned long
359 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
360 			  unsigned long len, unsigned long pgoff,
361 			  unsigned long flags);
362 extern void arch_unmap_area(struct mm_struct *, unsigned long);
363 extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
364 
365 #if USE_SPLIT_PTLOCKS
366 /*
367  * The mm counters are not protected by its page_table_lock,
368  * so must be incremented atomically.
369  */
370 #define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
371 #define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
372 #define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
373 #define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
374 #define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
375 
376 #else  /* !USE_SPLIT_PTLOCKS */
377 /*
378  * The mm counters are protected by its page_table_lock,
379  * so can be incremented directly.
380  */
381 #define set_mm_counter(mm, member, value) (mm)->_##member = (value)
382 #define get_mm_counter(mm, member) ((mm)->_##member)
383 #define add_mm_counter(mm, member, value) (mm)->_##member += (value)
384 #define inc_mm_counter(mm, member) (mm)->_##member++
385 #define dec_mm_counter(mm, member) (mm)->_##member--
386 
387 #endif /* !USE_SPLIT_PTLOCKS */
388 
389 #define get_mm_rss(mm)					\
390 	(get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
391 #define update_hiwater_rss(mm)	do {			\
392 	unsigned long _rss = get_mm_rss(mm);		\
393 	if ((mm)->hiwater_rss < _rss)			\
394 		(mm)->hiwater_rss = _rss;		\
395 } while (0)
396 #define update_hiwater_vm(mm)	do {			\
397 	if ((mm)->hiwater_vm < (mm)->total_vm)		\
398 		(mm)->hiwater_vm = (mm)->total_vm;	\
399 } while (0)
400 
401 static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm)
402 {
403 	return max(mm->hiwater_rss, get_mm_rss(mm));
404 }
405 
406 static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm)
407 {
408 	return max(mm->hiwater_vm, mm->total_vm);
409 }
410 
411 extern void set_dumpable(struct mm_struct *mm, int value);
412 extern int get_dumpable(struct mm_struct *mm);
413 
414 /* mm flags */
415 /* dumpable bits */
416 #define MMF_DUMPABLE      0  /* core dump is permitted */
417 #define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
418 #define MMF_DUMPABLE_BITS 2
419 
420 /* coredump filter bits */
421 #define MMF_DUMP_ANON_PRIVATE	2
422 #define MMF_DUMP_ANON_SHARED	3
423 #define MMF_DUMP_MAPPED_PRIVATE	4
424 #define MMF_DUMP_MAPPED_SHARED	5
425 #define MMF_DUMP_ELF_HEADERS	6
426 #define MMF_DUMP_HUGETLB_PRIVATE 7
427 #define MMF_DUMP_HUGETLB_SHARED  8
428 #define MMF_DUMP_FILTER_SHIFT	MMF_DUMPABLE_BITS
429 #define MMF_DUMP_FILTER_BITS	7
430 #define MMF_DUMP_FILTER_MASK \
431 	(((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
432 #define MMF_DUMP_FILTER_DEFAULT \
433 	((1 << MMF_DUMP_ANON_PRIVATE) |	(1 << MMF_DUMP_ANON_SHARED) |\
434 	 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
435 
436 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
437 # define MMF_DUMP_MASK_DEFAULT_ELF	(1 << MMF_DUMP_ELF_HEADERS)
438 #else
439 # define MMF_DUMP_MASK_DEFAULT_ELF	0
440 #endif
441 
442 struct sighand_struct {
443 	atomic_t		count;
444 	struct k_sigaction	action[_NSIG];
445 	spinlock_t		siglock;
446 	wait_queue_head_t	signalfd_wqh;
447 };
448 
449 struct pacct_struct {
450 	int			ac_flag;
451 	long			ac_exitcode;
452 	unsigned long		ac_mem;
453 	cputime_t		ac_utime, ac_stime;
454 	unsigned long		ac_minflt, ac_majflt;
455 };
456 
457 /**
458  * struct task_cputime - collected CPU time counts
459  * @utime:		time spent in user mode, in &cputime_t units
460  * @stime:		time spent in kernel mode, in &cputime_t units
461  * @sum_exec_runtime:	total time spent on the CPU, in nanoseconds
462  *
463  * This structure groups together three kinds of CPU time that are
464  * tracked for threads and thread groups.  Most things considering
465  * CPU time want to group these counts together and treat all three
466  * of them in parallel.
467  */
468 struct task_cputime {
469 	cputime_t utime;
470 	cputime_t stime;
471 	unsigned long long sum_exec_runtime;
472 };
473 /* Alternate field names when used to cache expirations. */
474 #define prof_exp	stime
475 #define virt_exp	utime
476 #define sched_exp	sum_exec_runtime
477 
478 #define INIT_CPUTIME	\
479 	(struct task_cputime) {					\
480 		.utime = cputime_zero,				\
481 		.stime = cputime_zero,				\
482 		.sum_exec_runtime = 0,				\
483 	}
484 
485 /**
486  * struct thread_group_cputimer - thread group interval timer counts
487  * @cputime:		thread group interval timers.
488  * @running:		non-zero when there are timers running and
489  * 			@cputime receives updates.
490  * @lock:		lock for fields in this struct.
491  *
492  * This structure contains the version of task_cputime, above, that is
493  * used for thread group CPU timer calculations.
494  */
495 struct thread_group_cputimer {
496 	struct task_cputime cputime;
497 	int running;
498 	spinlock_t lock;
499 };
500 
501 /*
502  * NOTE! "signal_struct" does not have it's own
503  * locking, because a shared signal_struct always
504  * implies a shared sighand_struct, so locking
505  * sighand_struct is always a proper superset of
506  * the locking of signal_struct.
507  */
508 struct signal_struct {
509 	atomic_t		count;
510 	atomic_t		live;
511 
512 	wait_queue_head_t	wait_chldexit;	/* for wait4() */
513 
514 	/* current thread group signal load-balancing target: */
515 	struct task_struct	*curr_target;
516 
517 	/* shared signal handling: */
518 	struct sigpending	shared_pending;
519 
520 	/* thread group exit support */
521 	int			group_exit_code;
522 	/* overloaded:
523 	 * - notify group_exit_task when ->count is equal to notify_count
524 	 * - everyone except group_exit_task is stopped during signal delivery
525 	 *   of fatal signals, group_exit_task processes the signal.
526 	 */
527 	int			notify_count;
528 	struct task_struct	*group_exit_task;
529 
530 	/* thread group stop support, overloads group_exit_code too */
531 	int			group_stop_count;
532 	unsigned int		flags; /* see SIGNAL_* flags below */
533 
534 	/* POSIX.1b Interval Timers */
535 	struct list_head posix_timers;
536 
537 	/* ITIMER_REAL timer for the process */
538 	struct hrtimer real_timer;
539 	struct pid *leader_pid;
540 	ktime_t it_real_incr;
541 
542 	/* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
543 	cputime_t it_prof_expires, it_virt_expires;
544 	cputime_t it_prof_incr, it_virt_incr;
545 
546 	/*
547 	 * Thread group totals for process CPU timers.
548 	 * See thread_group_cputimer(), et al, for details.
549 	 */
550 	struct thread_group_cputimer cputimer;
551 
552 	/* Earliest-expiration cache. */
553 	struct task_cputime cputime_expires;
554 
555 	struct list_head cpu_timers[3];
556 
557 	struct pid *tty_old_pgrp;
558 
559 	/* boolean value for session group leader */
560 	int leader;
561 
562 	struct tty_struct *tty; /* NULL if no tty */
563 
564 	/*
565 	 * Cumulative resource counters for dead threads in the group,
566 	 * and for reaped dead child processes forked by this group.
567 	 * Live threads maintain their own counters and add to these
568 	 * in __exit_signal, except for the group leader.
569 	 */
570 	cputime_t utime, stime, cutime, cstime;
571 	cputime_t gtime;
572 	cputime_t cgtime;
573 	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
574 	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
575 	unsigned long inblock, oublock, cinblock, coublock;
576 	struct task_io_accounting ioac;
577 
578 	/*
579 	 * Cumulative ns of schedule CPU time fo dead threads in the
580 	 * group, not including a zombie group leader, (This only differs
581 	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
582 	 * other than jiffies.)
583 	 */
584 	unsigned long long sum_sched_runtime;
585 
586 	/*
587 	 * We don't bother to synchronize most readers of this at all,
588 	 * because there is no reader checking a limit that actually needs
589 	 * to get both rlim_cur and rlim_max atomically, and either one
590 	 * alone is a single word that can safely be read normally.
591 	 * getrlimit/setrlimit use task_lock(current->group_leader) to
592 	 * protect this instead of the siglock, because they really
593 	 * have no need to disable irqs.
594 	 */
595 	struct rlimit rlim[RLIM_NLIMITS];
596 
597 #ifdef CONFIG_BSD_PROCESS_ACCT
598 	struct pacct_struct pacct;	/* per-process accounting information */
599 #endif
600 #ifdef CONFIG_TASKSTATS
601 	struct taskstats *stats;
602 #endif
603 #ifdef CONFIG_AUDIT
604 	unsigned audit_tty;
605 	struct tty_audit_buf *tty_audit_buf;
606 #endif
607 };
608 
609 /* Context switch must be unlocked if interrupts are to be enabled */
610 #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
611 # define __ARCH_WANT_UNLOCKED_CTXSW
612 #endif
613 
614 /*
615  * Bits in flags field of signal_struct.
616  */
617 #define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
618 #define SIGNAL_STOP_DEQUEUED	0x00000002 /* stop signal dequeued */
619 #define SIGNAL_STOP_CONTINUED	0x00000004 /* SIGCONT since WCONTINUED reap */
620 #define SIGNAL_GROUP_EXIT	0x00000008 /* group exit in progress */
621 /*
622  * Pending notifications to parent.
623  */
624 #define SIGNAL_CLD_STOPPED	0x00000010
625 #define SIGNAL_CLD_CONTINUED	0x00000020
626 #define SIGNAL_CLD_MASK		(SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
627 
628 #define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */
629 
630 /* If true, all threads except ->group_exit_task have pending SIGKILL */
631 static inline int signal_group_exit(const struct signal_struct *sig)
632 {
633 	return	(sig->flags & SIGNAL_GROUP_EXIT) ||
634 		(sig->group_exit_task != NULL);
635 }
636 
637 /*
638  * Some day this will be a full-fledged user tracking system..
639  */
640 struct user_struct {
641 	atomic_t __count;	/* reference count */
642 	atomic_t processes;	/* How many processes does this user have? */
643 	atomic_t files;		/* How many open files does this user have? */
644 	atomic_t sigpending;	/* How many pending signals does this user have? */
645 #ifdef CONFIG_INOTIFY_USER
646 	atomic_t inotify_watches; /* How many inotify watches does this user have? */
647 	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
648 #endif
649 #ifdef CONFIG_EPOLL
650 	atomic_t epoll_watches;	/* The number of file descriptors currently watched */
651 #endif
652 #ifdef CONFIG_POSIX_MQUEUE
653 	/* protected by mq_lock	*/
654 	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
655 #endif
656 	unsigned long locked_shm; /* How many pages of mlocked shm ? */
657 
658 #ifdef CONFIG_KEYS
659 	struct key *uid_keyring;	/* UID specific keyring */
660 	struct key *session_keyring;	/* UID's default session keyring */
661 #endif
662 
663 	/* Hash table maintenance information */
664 	struct hlist_node uidhash_node;
665 	uid_t uid;
666 	struct user_namespace *user_ns;
667 
668 #ifdef CONFIG_USER_SCHED
669 	struct task_group *tg;
670 #ifdef CONFIG_SYSFS
671 	struct kobject kobj;
672 	struct work_struct work;
673 #endif
674 #endif
675 };
676 
677 extern int uids_sysfs_init(void);
678 
679 extern struct user_struct *find_user(uid_t);
680 
681 extern struct user_struct root_user;
682 #define INIT_USER (&root_user)
683 
684 
685 struct backing_dev_info;
686 struct reclaim_state;
687 
688 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
689 struct sched_info {
690 	/* cumulative counters */
691 	unsigned long pcount;	      /* # of times run on this cpu */
692 	unsigned long long run_delay; /* time spent waiting on a runqueue */
693 
694 	/* timestamps */
695 	unsigned long long last_arrival,/* when we last ran on a cpu */
696 			   last_queued;	/* when we were last queued to run */
697 #ifdef CONFIG_SCHEDSTATS
698 	/* BKL stats */
699 	unsigned int bkl_count;
700 #endif
701 };
702 #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
703 
704 #ifdef CONFIG_TASK_DELAY_ACCT
705 struct task_delay_info {
706 	spinlock_t	lock;
707 	unsigned int	flags;	/* Private per-task flags */
708 
709 	/* For each stat XXX, add following, aligned appropriately
710 	 *
711 	 * struct timespec XXX_start, XXX_end;
712 	 * u64 XXX_delay;
713 	 * u32 XXX_count;
714 	 *
715 	 * Atomicity of updates to XXX_delay, XXX_count protected by
716 	 * single lock above (split into XXX_lock if contention is an issue).
717 	 */
718 
719 	/*
720 	 * XXX_count is incremented on every XXX operation, the delay
721 	 * associated with the operation is added to XXX_delay.
722 	 * XXX_delay contains the accumulated delay time in nanoseconds.
723 	 */
724 	struct timespec blkio_start, blkio_end;	/* Shared by blkio, swapin */
725 	u64 blkio_delay;	/* wait for sync block io completion */
726 	u64 swapin_delay;	/* wait for swapin block io completion */
727 	u32 blkio_count;	/* total count of the number of sync block */
728 				/* io operations performed */
729 	u32 swapin_count;	/* total count of the number of swapin block */
730 				/* io operations performed */
731 
732 	struct timespec freepages_start, freepages_end;
733 	u64 freepages_delay;	/* wait for memory reclaim */
734 	u32 freepages_count;	/* total count of memory reclaim */
735 };
736 #endif	/* CONFIG_TASK_DELAY_ACCT */
737 
738 static inline int sched_info_on(void)
739 {
740 #ifdef CONFIG_SCHEDSTATS
741 	return 1;
742 #elif defined(CONFIG_TASK_DELAY_ACCT)
743 	extern int delayacct_on;
744 	return delayacct_on;
745 #else
746 	return 0;
747 #endif
748 }
749 
750 enum cpu_idle_type {
751 	CPU_IDLE,
752 	CPU_NOT_IDLE,
753 	CPU_NEWLY_IDLE,
754 	CPU_MAX_IDLE_TYPES
755 };
756 
757 /*
758  * sched-domains (multiprocessor balancing) declarations:
759  */
760 
761 /*
762  * Increase resolution of nice-level calculations:
763  */
764 #define SCHED_LOAD_SHIFT	10
765 #define SCHED_LOAD_SCALE	(1L << SCHED_LOAD_SHIFT)
766 
767 #define SCHED_LOAD_SCALE_FUZZ	SCHED_LOAD_SCALE
768 
769 #ifdef CONFIG_SMP
770 #define SD_LOAD_BALANCE		1	/* Do load balancing on this domain. */
771 #define SD_BALANCE_NEWIDLE	2	/* Balance when about to become idle */
772 #define SD_BALANCE_EXEC		4	/* Balance on exec */
773 #define SD_BALANCE_FORK		8	/* Balance on fork, clone */
774 #define SD_WAKE_IDLE		16	/* Wake to idle CPU on task wakeup */
775 #define SD_WAKE_AFFINE		32	/* Wake task to waking CPU */
776 #define SD_WAKE_BALANCE		64	/* Perform balancing at task wakeup */
777 #define SD_SHARE_CPUPOWER	128	/* Domain members share cpu power */
778 #define SD_POWERSAVINGS_BALANCE	256	/* Balance for power savings */
779 #define SD_SHARE_PKG_RESOURCES	512	/* Domain members share cpu pkg resources */
780 #define SD_SERIALIZE		1024	/* Only a single load balancing instance */
781 #define SD_WAKE_IDLE_FAR	2048	/* Gain latency sacrificing cache hit */
782 
783 enum powersavings_balance_level {
784 	POWERSAVINGS_BALANCE_NONE = 0,  /* No power saving load balance */
785 	POWERSAVINGS_BALANCE_BASIC,	/* Fill one thread/core/package
786 					 * first for long running threads
787 					 */
788 	POWERSAVINGS_BALANCE_WAKEUP,	/* Also bias task wakeups to semi-idle
789 					 * cpu package for power savings
790 					 */
791 	MAX_POWERSAVINGS_BALANCE_LEVELS
792 };
793 
794 extern int sched_mc_power_savings, sched_smt_power_savings;
795 
796 static inline int sd_balance_for_mc_power(void)
797 {
798 	if (sched_smt_power_savings)
799 		return SD_POWERSAVINGS_BALANCE;
800 
801 	return 0;
802 }
803 
804 static inline int sd_balance_for_package_power(void)
805 {
806 	if (sched_mc_power_savings | sched_smt_power_savings)
807 		return SD_POWERSAVINGS_BALANCE;
808 
809 	return 0;
810 }
811 
812 /*
813  * Optimise SD flags for power savings:
814  * SD_BALANCE_NEWIDLE helps agressive task consolidation and power savings.
815  * Keep default SD flags if sched_{smt,mc}_power_saving=0
816  */
817 
818 static inline int sd_power_saving_flags(void)
819 {
820 	if (sched_mc_power_savings | sched_smt_power_savings)
821 		return SD_BALANCE_NEWIDLE;
822 
823 	return 0;
824 }
825 
826 struct sched_group {
827 	struct sched_group *next;	/* Must be a circular list */
828 
829 	/*
830 	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
831 	 * single CPU. This is read only (except for setup, hotplug CPU).
832 	 * Note : Never change cpu_power without recompute its reciprocal
833 	 */
834 	unsigned int __cpu_power;
835 	/*
836 	 * reciprocal value of cpu_power to avoid expensive divides
837 	 * (see include/linux/reciprocal_div.h)
838 	 */
839 	u32 reciprocal_cpu_power;
840 
841 	unsigned long cpumask[];
842 };
843 
844 static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
845 {
846 	return to_cpumask(sg->cpumask);
847 }
848 
849 enum sched_domain_level {
850 	SD_LV_NONE = 0,
851 	SD_LV_SIBLING,
852 	SD_LV_MC,
853 	SD_LV_CPU,
854 	SD_LV_NODE,
855 	SD_LV_ALLNODES,
856 	SD_LV_MAX
857 };
858 
859 struct sched_domain_attr {
860 	int relax_domain_level;
861 };
862 
863 #define SD_ATTR_INIT	(struct sched_domain_attr) {	\
864 	.relax_domain_level = -1,			\
865 }
866 
867 struct sched_domain {
868 	/* These fields must be setup */
869 	struct sched_domain *parent;	/* top domain must be null terminated */
870 	struct sched_domain *child;	/* bottom domain must be null terminated */
871 	struct sched_group *groups;	/* the balancing groups of the domain */
872 	unsigned long min_interval;	/* Minimum balance interval ms */
873 	unsigned long max_interval;	/* Maximum balance interval ms */
874 	unsigned int busy_factor;	/* less balancing by factor if busy */
875 	unsigned int imbalance_pct;	/* No balance until over watermark */
876 	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
877 	unsigned int busy_idx;
878 	unsigned int idle_idx;
879 	unsigned int newidle_idx;
880 	unsigned int wake_idx;
881 	unsigned int forkexec_idx;
882 	int flags;			/* See SD_* */
883 	enum sched_domain_level level;
884 
885 	/* Runtime fields. */
886 	unsigned long last_balance;	/* init to jiffies. units in jiffies */
887 	unsigned int balance_interval;	/* initialise to 1. units in ms. */
888 	unsigned int nr_balance_failed; /* initialise to 0 */
889 
890 	u64 last_update;
891 
892 #ifdef CONFIG_SCHEDSTATS
893 	/* load_balance() stats */
894 	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
895 	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
896 	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
897 	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
898 	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
899 	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
900 	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
901 	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
902 
903 	/* Active load balancing */
904 	unsigned int alb_count;
905 	unsigned int alb_failed;
906 	unsigned int alb_pushed;
907 
908 	/* SD_BALANCE_EXEC stats */
909 	unsigned int sbe_count;
910 	unsigned int sbe_balanced;
911 	unsigned int sbe_pushed;
912 
913 	/* SD_BALANCE_FORK stats */
914 	unsigned int sbf_count;
915 	unsigned int sbf_balanced;
916 	unsigned int sbf_pushed;
917 
918 	/* try_to_wake_up() stats */
919 	unsigned int ttwu_wake_remote;
920 	unsigned int ttwu_move_affine;
921 	unsigned int ttwu_move_balance;
922 #endif
923 #ifdef CONFIG_SCHED_DEBUG
924 	char *name;
925 #endif
926 
927 	/* span of all CPUs in this domain */
928 	unsigned long span[];
929 };
930 
931 static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
932 {
933 	return to_cpumask(sd->span);
934 }
935 
936 extern void partition_sched_domains(int ndoms_new, struct cpumask *doms_new,
937 				    struct sched_domain_attr *dattr_new);
938 
939 /* Test a flag in parent sched domain */
940 static inline int test_sd_parent(struct sched_domain *sd, int flag)
941 {
942 	if (sd->parent && (sd->parent->flags & flag))
943 		return 1;
944 
945 	return 0;
946 }
947 
948 #else /* CONFIG_SMP */
949 
950 struct sched_domain_attr;
951 
952 static inline void
953 partition_sched_domains(int ndoms_new, struct cpumask *doms_new,
954 			struct sched_domain_attr *dattr_new)
955 {
956 }
957 #endif	/* !CONFIG_SMP */
958 
959 struct io_context;			/* See blkdev.h */
960 
961 
962 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
963 extern void prefetch_stack(struct task_struct *t);
964 #else
965 static inline void prefetch_stack(struct task_struct *t) { }
966 #endif
967 
968 struct audit_context;		/* See audit.c */
969 struct mempolicy;
970 struct pipe_inode_info;
971 struct uts_namespace;
972 
973 struct rq;
974 struct sched_domain;
975 
976 struct sched_class {
977 	const struct sched_class *next;
978 
979 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int wakeup);
980 	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int sleep);
981 	void (*yield_task) (struct rq *rq);
982 
983 	void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int sync);
984 
985 	struct task_struct * (*pick_next_task) (struct rq *rq);
986 	void (*put_prev_task) (struct rq *rq, struct task_struct *p);
987 
988 #ifdef CONFIG_SMP
989 	int  (*select_task_rq)(struct task_struct *p, int sync);
990 
991 	unsigned long (*load_balance) (struct rq *this_rq, int this_cpu,
992 			struct rq *busiest, unsigned long max_load_move,
993 			struct sched_domain *sd, enum cpu_idle_type idle,
994 			int *all_pinned, int *this_best_prio);
995 
996 	int (*move_one_task) (struct rq *this_rq, int this_cpu,
997 			      struct rq *busiest, struct sched_domain *sd,
998 			      enum cpu_idle_type idle);
999 	void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
1000 	int (*needs_post_schedule) (struct rq *this_rq);
1001 	void (*post_schedule) (struct rq *this_rq);
1002 	void (*task_wake_up) (struct rq *this_rq, struct task_struct *task);
1003 
1004 	void (*set_cpus_allowed)(struct task_struct *p,
1005 				 const struct cpumask *newmask);
1006 
1007 	void (*rq_online)(struct rq *rq);
1008 	void (*rq_offline)(struct rq *rq);
1009 #endif
1010 
1011 	void (*set_curr_task) (struct rq *rq);
1012 	void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1013 	void (*task_new) (struct rq *rq, struct task_struct *p);
1014 
1015 	void (*switched_from) (struct rq *this_rq, struct task_struct *task,
1016 			       int running);
1017 	void (*switched_to) (struct rq *this_rq, struct task_struct *task,
1018 			     int running);
1019 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1020 			     int oldprio, int running);
1021 
1022 #ifdef CONFIG_FAIR_GROUP_SCHED
1023 	void (*moved_group) (struct task_struct *p);
1024 #endif
1025 };
1026 
1027 struct load_weight {
1028 	unsigned long weight, inv_weight;
1029 };
1030 
1031 /*
1032  * CFS stats for a schedulable entity (task, task-group etc)
1033  *
1034  * Current field usage histogram:
1035  *
1036  *     4 se->block_start
1037  *     4 se->run_node
1038  *     4 se->sleep_start
1039  *     6 se->load.weight
1040  */
1041 struct sched_entity {
1042 	struct load_weight	load;		/* for load-balancing */
1043 	struct rb_node		run_node;
1044 	struct list_head	group_node;
1045 	unsigned int		on_rq;
1046 
1047 	u64			exec_start;
1048 	u64			sum_exec_runtime;
1049 	u64			vruntime;
1050 	u64			prev_sum_exec_runtime;
1051 
1052 	u64			last_wakeup;
1053 	u64			avg_overlap;
1054 
1055 	u64			start_runtime;
1056 	u64			avg_wakeup;
1057 	u64			nr_migrations;
1058 
1059 #ifdef CONFIG_SCHEDSTATS
1060 	u64			wait_start;
1061 	u64			wait_max;
1062 	u64			wait_count;
1063 	u64			wait_sum;
1064 
1065 	u64			sleep_start;
1066 	u64			sleep_max;
1067 	s64			sum_sleep_runtime;
1068 
1069 	u64			block_start;
1070 	u64			block_max;
1071 	u64			exec_max;
1072 	u64			slice_max;
1073 
1074 	u64			nr_migrations_cold;
1075 	u64			nr_failed_migrations_affine;
1076 	u64			nr_failed_migrations_running;
1077 	u64			nr_failed_migrations_hot;
1078 	u64			nr_forced_migrations;
1079 	u64			nr_forced2_migrations;
1080 
1081 	u64			nr_wakeups;
1082 	u64			nr_wakeups_sync;
1083 	u64			nr_wakeups_migrate;
1084 	u64			nr_wakeups_local;
1085 	u64			nr_wakeups_remote;
1086 	u64			nr_wakeups_affine;
1087 	u64			nr_wakeups_affine_attempts;
1088 	u64			nr_wakeups_passive;
1089 	u64			nr_wakeups_idle;
1090 #endif
1091 
1092 #ifdef CONFIG_FAIR_GROUP_SCHED
1093 	struct sched_entity	*parent;
1094 	/* rq on which this entity is (to be) queued: */
1095 	struct cfs_rq		*cfs_rq;
1096 	/* rq "owned" by this entity/group: */
1097 	struct cfs_rq		*my_q;
1098 #endif
1099 };
1100 
1101 struct sched_rt_entity {
1102 	struct list_head run_list;
1103 	unsigned long timeout;
1104 	unsigned int time_slice;
1105 	int nr_cpus_allowed;
1106 
1107 	struct sched_rt_entity *back;
1108 #ifdef CONFIG_RT_GROUP_SCHED
1109 	struct sched_rt_entity	*parent;
1110 	/* rq on which this entity is (to be) queued: */
1111 	struct rt_rq		*rt_rq;
1112 	/* rq "owned" by this entity/group: */
1113 	struct rt_rq		*my_q;
1114 #endif
1115 };
1116 
1117 struct task_struct {
1118 	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
1119 	void *stack;
1120 	atomic_t usage;
1121 	unsigned int flags;	/* per process flags, defined below */
1122 	unsigned int ptrace;
1123 
1124 	int lock_depth;		/* BKL lock depth */
1125 
1126 #ifdef CONFIG_SMP
1127 #ifdef __ARCH_WANT_UNLOCKED_CTXSW
1128 	int oncpu;
1129 #endif
1130 #endif
1131 
1132 	int prio, static_prio, normal_prio;
1133 	unsigned int rt_priority;
1134 	const struct sched_class *sched_class;
1135 	struct sched_entity se;
1136 	struct sched_rt_entity rt;
1137 
1138 #ifdef CONFIG_PREEMPT_NOTIFIERS
1139 	/* list of struct preempt_notifier: */
1140 	struct hlist_head preempt_notifiers;
1141 #endif
1142 
1143 	/*
1144 	 * fpu_counter contains the number of consecutive context switches
1145 	 * that the FPU is used. If this is over a threshold, the lazy fpu
1146 	 * saving becomes unlazy to save the trap. This is an unsigned char
1147 	 * so that after 256 times the counter wraps and the behavior turns
1148 	 * lazy again; this to deal with bursty apps that only use FPU for
1149 	 * a short time
1150 	 */
1151 	unsigned char fpu_counter;
1152 	s8 oomkilladj; /* OOM kill score adjustment (bit shift). */
1153 #ifdef CONFIG_BLK_DEV_IO_TRACE
1154 	unsigned int btrace_seq;
1155 #endif
1156 
1157 	unsigned int policy;
1158 	cpumask_t cpus_allowed;
1159 
1160 #ifdef CONFIG_PREEMPT_RCU
1161 	int rcu_read_lock_nesting;
1162 	int rcu_flipctr_idx;
1163 #endif /* #ifdef CONFIG_PREEMPT_RCU */
1164 
1165 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1166 	struct sched_info sched_info;
1167 #endif
1168 
1169 	struct list_head tasks;
1170 	struct plist_node pushable_tasks;
1171 
1172 	struct mm_struct *mm, *active_mm;
1173 
1174 /* task state */
1175 	struct linux_binfmt *binfmt;
1176 	int exit_state;
1177 	int exit_code, exit_signal;
1178 	int pdeath_signal;  /*  The signal sent when the parent dies  */
1179 	/* ??? */
1180 	unsigned int personality;
1181 	unsigned did_exec:1;
1182 	unsigned in_execve:1;	/* Tell the LSMs that the process is doing an
1183 				 * execve */
1184 	pid_t pid;
1185 	pid_t tgid;
1186 
1187 	/* Canary value for the -fstack-protector gcc feature */
1188 	unsigned long stack_canary;
1189 
1190 	/*
1191 	 * pointers to (original) parent process, youngest child, younger sibling,
1192 	 * older sibling, respectively.  (p->father can be replaced with
1193 	 * p->real_parent->pid)
1194 	 */
1195 	struct task_struct *real_parent; /* real parent process */
1196 	struct task_struct *parent; /* recipient of SIGCHLD, wait4() reports */
1197 	/*
1198 	 * children/sibling forms the list of my natural children
1199 	 */
1200 	struct list_head children;	/* list of my children */
1201 	struct list_head sibling;	/* linkage in my parent's children list */
1202 	struct task_struct *group_leader;	/* threadgroup leader */
1203 
1204 	/*
1205 	 * ptraced is the list of tasks this task is using ptrace on.
1206 	 * This includes both natural children and PTRACE_ATTACH targets.
1207 	 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1208 	 */
1209 	struct list_head ptraced;
1210 	struct list_head ptrace_entry;
1211 
1212 #ifdef CONFIG_X86_PTRACE_BTS
1213 	/*
1214 	 * This is the tracer handle for the ptrace BTS extension.
1215 	 * This field actually belongs to the ptracer task.
1216 	 */
1217 	struct bts_tracer *bts;
1218 	/*
1219 	 * The buffer to hold the BTS data.
1220 	 */
1221 	void *bts_buffer;
1222 	size_t bts_size;
1223 #endif /* CONFIG_X86_PTRACE_BTS */
1224 
1225 	/* PID/PID hash table linkage. */
1226 	struct pid_link pids[PIDTYPE_MAX];
1227 	struct list_head thread_group;
1228 
1229 	struct completion *vfork_done;		/* for vfork() */
1230 	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
1231 	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
1232 
1233 	cputime_t utime, stime, utimescaled, stimescaled;
1234 	cputime_t gtime;
1235 	cputime_t prev_utime, prev_stime;
1236 	unsigned long nvcsw, nivcsw; /* context switch counts */
1237 	struct timespec start_time; 		/* monotonic time */
1238 	struct timespec real_start_time;	/* boot based time */
1239 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1240 	unsigned long min_flt, maj_flt;
1241 
1242 	struct task_cputime cputime_expires;
1243 	struct list_head cpu_timers[3];
1244 
1245 /* process credentials */
1246 	const struct cred *real_cred;	/* objective and real subjective task
1247 					 * credentials (COW) */
1248 	const struct cred *cred;	/* effective (overridable) subjective task
1249 					 * credentials (COW) */
1250 	struct mutex cred_exec_mutex;	/* execve vs ptrace cred calculation mutex */
1251 
1252 	char comm[TASK_COMM_LEN]; /* executable name excluding path
1253 				     - access with [gs]et_task_comm (which lock
1254 				       it with task_lock())
1255 				     - initialized normally by flush_old_exec */
1256 /* file system info */
1257 	int link_count, total_link_count;
1258 #ifdef CONFIG_SYSVIPC
1259 /* ipc stuff */
1260 	struct sysv_sem sysvsem;
1261 #endif
1262 #ifdef CONFIG_DETECT_HUNG_TASK
1263 /* hung task detection */
1264 	unsigned long last_switch_count;
1265 #endif
1266 /* CPU-specific state of this task */
1267 	struct thread_struct thread;
1268 /* filesystem information */
1269 	struct fs_struct *fs;
1270 /* open file information */
1271 	struct files_struct *files;
1272 /* namespaces */
1273 	struct nsproxy *nsproxy;
1274 /* signal handlers */
1275 	struct signal_struct *signal;
1276 	struct sighand_struct *sighand;
1277 
1278 	sigset_t blocked, real_blocked;
1279 	sigset_t saved_sigmask;	/* restored if set_restore_sigmask() was used */
1280 	struct sigpending pending;
1281 
1282 	unsigned long sas_ss_sp;
1283 	size_t sas_ss_size;
1284 	int (*notifier)(void *priv);
1285 	void *notifier_data;
1286 	sigset_t *notifier_mask;
1287 	struct audit_context *audit_context;
1288 #ifdef CONFIG_AUDITSYSCALL
1289 	uid_t loginuid;
1290 	unsigned int sessionid;
1291 #endif
1292 	seccomp_t seccomp;
1293 
1294 /* Thread group tracking */
1295    	u32 parent_exec_id;
1296    	u32 self_exec_id;
1297 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
1298 	spinlock_t alloc_lock;
1299 
1300 #ifdef CONFIG_GENERIC_HARDIRQS
1301 	/* IRQ handler threads */
1302 	struct irqaction *irqaction;
1303 #endif
1304 
1305 	/* Protection of the PI data structures: */
1306 	spinlock_t pi_lock;
1307 
1308 #ifdef CONFIG_RT_MUTEXES
1309 	/* PI waiters blocked on a rt_mutex held by this task */
1310 	struct plist_head pi_waiters;
1311 	/* Deadlock detection and priority inheritance handling */
1312 	struct rt_mutex_waiter *pi_blocked_on;
1313 #endif
1314 
1315 #ifdef CONFIG_DEBUG_MUTEXES
1316 	/* mutex deadlock detection */
1317 	struct mutex_waiter *blocked_on;
1318 #endif
1319 #ifdef CONFIG_TRACE_IRQFLAGS
1320 	unsigned int irq_events;
1321 	int hardirqs_enabled;
1322 	unsigned long hardirq_enable_ip;
1323 	unsigned int hardirq_enable_event;
1324 	unsigned long hardirq_disable_ip;
1325 	unsigned int hardirq_disable_event;
1326 	int softirqs_enabled;
1327 	unsigned long softirq_disable_ip;
1328 	unsigned int softirq_disable_event;
1329 	unsigned long softirq_enable_ip;
1330 	unsigned int softirq_enable_event;
1331 	int hardirq_context;
1332 	int softirq_context;
1333 #endif
1334 #ifdef CONFIG_LOCKDEP
1335 # define MAX_LOCK_DEPTH 48UL
1336 	u64 curr_chain_key;
1337 	int lockdep_depth;
1338 	unsigned int lockdep_recursion;
1339 	struct held_lock held_locks[MAX_LOCK_DEPTH];
1340 	gfp_t lockdep_reclaim_gfp;
1341 #endif
1342 
1343 /* journalling filesystem info */
1344 	void *journal_info;
1345 
1346 /* stacked block device info */
1347 	struct bio *bio_list, **bio_tail;
1348 
1349 /* VM state */
1350 	struct reclaim_state *reclaim_state;
1351 
1352 	struct backing_dev_info *backing_dev_info;
1353 
1354 	struct io_context *io_context;
1355 
1356 	unsigned long ptrace_message;
1357 	siginfo_t *last_siginfo; /* For ptrace use.  */
1358 	struct task_io_accounting ioac;
1359 #if defined(CONFIG_TASK_XACCT)
1360 	u64 acct_rss_mem1;	/* accumulated rss usage */
1361 	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1362 	cputime_t acct_timexpd;	/* stime + utime since last update */
1363 #endif
1364 #ifdef CONFIG_CPUSETS
1365 	nodemask_t mems_allowed;
1366 	int cpuset_mems_generation;
1367 	int cpuset_mem_spread_rotor;
1368 #endif
1369 #ifdef CONFIG_CGROUPS
1370 	/* Control Group info protected by css_set_lock */
1371 	struct css_set *cgroups;
1372 	/* cg_list protected by css_set_lock and tsk->alloc_lock */
1373 	struct list_head cg_list;
1374 #endif
1375 #ifdef CONFIG_FUTEX
1376 	struct robust_list_head __user *robust_list;
1377 #ifdef CONFIG_COMPAT
1378 	struct compat_robust_list_head __user *compat_robust_list;
1379 #endif
1380 	struct list_head pi_state_list;
1381 	struct futex_pi_state *pi_state_cache;
1382 #endif
1383 #ifdef CONFIG_NUMA
1384 	struct mempolicy *mempolicy;
1385 	short il_next;
1386 #endif
1387 	atomic_t fs_excl;	/* holding fs exclusive resources */
1388 	struct rcu_head rcu;
1389 
1390 	/*
1391 	 * cache last used pipe for splice
1392 	 */
1393 	struct pipe_inode_info *splice_pipe;
1394 #ifdef	CONFIG_TASK_DELAY_ACCT
1395 	struct task_delay_info *delays;
1396 #endif
1397 #ifdef CONFIG_FAULT_INJECTION
1398 	int make_it_fail;
1399 #endif
1400 	struct prop_local_single dirties;
1401 #ifdef CONFIG_LATENCYTOP
1402 	int latency_record_count;
1403 	struct latency_record latency_record[LT_SAVECOUNT];
1404 #endif
1405 	/*
1406 	 * time slack values; these are used to round up poll() and
1407 	 * select() etc timeout values. These are in nanoseconds.
1408 	 */
1409 	unsigned long timer_slack_ns;
1410 	unsigned long default_timer_slack_ns;
1411 
1412 	struct list_head	*scm_work_list;
1413 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1414 	/* Index of current stored adress in ret_stack */
1415 	int curr_ret_stack;
1416 	/* Stack of return addresses for return function tracing */
1417 	struct ftrace_ret_stack	*ret_stack;
1418 	/* time stamp for last schedule */
1419 	unsigned long long ftrace_timestamp;
1420 	/*
1421 	 * Number of functions that haven't been traced
1422 	 * because of depth overrun.
1423 	 */
1424 	atomic_t trace_overrun;
1425 	/* Pause for the tracing */
1426 	atomic_t tracing_graph_pause;
1427 #endif
1428 #ifdef CONFIG_TRACING
1429 	/* state flags for use by tracers */
1430 	unsigned long trace;
1431 #endif
1432 };
1433 
1434 /* Future-safe accessor for struct task_struct's cpus_allowed. */
1435 #define tsk_cpumask(tsk) (&(tsk)->cpus_allowed)
1436 
1437 /*
1438  * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1439  * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1440  * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1441  * values are inverted: lower p->prio value means higher priority.
1442  *
1443  * The MAX_USER_RT_PRIO value allows the actual maximum
1444  * RT priority to be separate from the value exported to
1445  * user-space.  This allows kernel threads to set their
1446  * priority to a value higher than any user task. Note:
1447  * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1448  */
1449 
1450 #define MAX_USER_RT_PRIO	100
1451 #define MAX_RT_PRIO		MAX_USER_RT_PRIO
1452 
1453 #define MAX_PRIO		(MAX_RT_PRIO + 40)
1454 #define DEFAULT_PRIO		(MAX_RT_PRIO + 20)
1455 
1456 static inline int rt_prio(int prio)
1457 {
1458 	if (unlikely(prio < MAX_RT_PRIO))
1459 		return 1;
1460 	return 0;
1461 }
1462 
1463 static inline int rt_task(struct task_struct *p)
1464 {
1465 	return rt_prio(p->prio);
1466 }
1467 
1468 static inline struct pid *task_pid(struct task_struct *task)
1469 {
1470 	return task->pids[PIDTYPE_PID].pid;
1471 }
1472 
1473 static inline struct pid *task_tgid(struct task_struct *task)
1474 {
1475 	return task->group_leader->pids[PIDTYPE_PID].pid;
1476 }
1477 
1478 /*
1479  * Without tasklist or rcu lock it is not safe to dereference
1480  * the result of task_pgrp/task_session even if task == current,
1481  * we can race with another thread doing sys_setsid/sys_setpgid.
1482  */
1483 static inline struct pid *task_pgrp(struct task_struct *task)
1484 {
1485 	return task->group_leader->pids[PIDTYPE_PGID].pid;
1486 }
1487 
1488 static inline struct pid *task_session(struct task_struct *task)
1489 {
1490 	return task->group_leader->pids[PIDTYPE_SID].pid;
1491 }
1492 
1493 struct pid_namespace;
1494 
1495 /*
1496  * the helpers to get the task's different pids as they are seen
1497  * from various namespaces
1498  *
1499  * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1500  * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1501  *                     current.
1502  * task_xid_nr_ns()  : id seen from the ns specified;
1503  *
1504  * set_task_vxid()   : assigns a virtual id to a task;
1505  *
1506  * see also pid_nr() etc in include/linux/pid.h
1507  */
1508 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1509 			struct pid_namespace *ns);
1510 
1511 static inline pid_t task_pid_nr(struct task_struct *tsk)
1512 {
1513 	return tsk->pid;
1514 }
1515 
1516 static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1517 					struct pid_namespace *ns)
1518 {
1519 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1520 }
1521 
1522 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1523 {
1524 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1525 }
1526 
1527 
1528 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1529 {
1530 	return tsk->tgid;
1531 }
1532 
1533 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1534 
1535 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1536 {
1537 	return pid_vnr(task_tgid(tsk));
1538 }
1539 
1540 
1541 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1542 					struct pid_namespace *ns)
1543 {
1544 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1545 }
1546 
1547 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1548 {
1549 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1550 }
1551 
1552 
1553 static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1554 					struct pid_namespace *ns)
1555 {
1556 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1557 }
1558 
1559 static inline pid_t task_session_vnr(struct task_struct *tsk)
1560 {
1561 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1562 }
1563 
1564 /* obsolete, do not use */
1565 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1566 {
1567 	return task_pgrp_nr_ns(tsk, &init_pid_ns);
1568 }
1569 
1570 /**
1571  * pid_alive - check that a task structure is not stale
1572  * @p: Task structure to be checked.
1573  *
1574  * Test if a process is not yet dead (at most zombie state)
1575  * If pid_alive fails, then pointers within the task structure
1576  * can be stale and must not be dereferenced.
1577  */
1578 static inline int pid_alive(struct task_struct *p)
1579 {
1580 	return p->pids[PIDTYPE_PID].pid != NULL;
1581 }
1582 
1583 /**
1584  * is_global_init - check if a task structure is init
1585  * @tsk: Task structure to be checked.
1586  *
1587  * Check if a task structure is the first user space task the kernel created.
1588  */
1589 static inline int is_global_init(struct task_struct *tsk)
1590 {
1591 	return tsk->pid == 1;
1592 }
1593 
1594 /*
1595  * is_container_init:
1596  * check whether in the task is init in its own pid namespace.
1597  */
1598 extern int is_container_init(struct task_struct *tsk);
1599 
1600 extern struct pid *cad_pid;
1601 
1602 extern void free_task(struct task_struct *tsk);
1603 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1604 
1605 extern void __put_task_struct(struct task_struct *t);
1606 
1607 static inline void put_task_struct(struct task_struct *t)
1608 {
1609 	if (atomic_dec_and_test(&t->usage))
1610 		__put_task_struct(t);
1611 }
1612 
1613 extern cputime_t task_utime(struct task_struct *p);
1614 extern cputime_t task_stime(struct task_struct *p);
1615 extern cputime_t task_gtime(struct task_struct *p);
1616 
1617 /*
1618  * Per process flags
1619  */
1620 #define PF_ALIGNWARN	0x00000001	/* Print alignment warning msgs */
1621 					/* Not implemented yet, only for 486*/
1622 #define PF_STARTING	0x00000002	/* being created */
1623 #define PF_EXITING	0x00000004	/* getting shut down */
1624 #define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
1625 #define PF_VCPU		0x00000010	/* I'm a virtual CPU */
1626 #define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
1627 #define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
1628 #define PF_DUMPCORE	0x00000200	/* dumped core */
1629 #define PF_SIGNALED	0x00000400	/* killed by a signal */
1630 #define PF_MEMALLOC	0x00000800	/* Allocating memory */
1631 #define PF_FLUSHER	0x00001000	/* responsible for disk writeback */
1632 #define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
1633 #define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
1634 #define PF_FROZEN	0x00010000	/* frozen for system suspend */
1635 #define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
1636 #define PF_KSWAPD	0x00040000	/* I am kswapd */
1637 #define PF_SWAPOFF	0x00080000	/* I am in swapoff */
1638 #define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
1639 #define PF_KTHREAD	0x00200000	/* I am a kernel thread */
1640 #define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
1641 #define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
1642 #define PF_SPREAD_PAGE	0x01000000	/* Spread page cache over cpuset */
1643 #define PF_SPREAD_SLAB	0x02000000	/* Spread some slab caches over cpuset */
1644 #define PF_THREAD_BOUND	0x04000000	/* Thread bound to specific cpu */
1645 #define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
1646 #define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
1647 #define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezeable */
1648 #define PF_FREEZER_NOSIG 0x80000000	/* Freezer won't send signals to it */
1649 
1650 /*
1651  * Only the _current_ task can read/write to tsk->flags, but other
1652  * tasks can access tsk->flags in readonly mode for example
1653  * with tsk_used_math (like during threaded core dumping).
1654  * There is however an exception to this rule during ptrace
1655  * or during fork: the ptracer task is allowed to write to the
1656  * child->flags of its traced child (same goes for fork, the parent
1657  * can write to the child->flags), because we're guaranteed the
1658  * child is not running and in turn not changing child->flags
1659  * at the same time the parent does it.
1660  */
1661 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1662 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1663 #define clear_used_math() clear_stopped_child_used_math(current)
1664 #define set_used_math() set_stopped_child_used_math(current)
1665 #define conditional_stopped_child_used_math(condition, child) \
1666 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1667 #define conditional_used_math(condition) \
1668 	conditional_stopped_child_used_math(condition, current)
1669 #define copy_to_stopped_child_used_math(child) \
1670 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1671 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1672 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1673 #define used_math() tsk_used_math(current)
1674 
1675 #ifdef CONFIG_SMP
1676 extern int set_cpus_allowed_ptr(struct task_struct *p,
1677 				const struct cpumask *new_mask);
1678 #else
1679 static inline int set_cpus_allowed_ptr(struct task_struct *p,
1680 				       const struct cpumask *new_mask)
1681 {
1682 	if (!cpumask_test_cpu(0, new_mask))
1683 		return -EINVAL;
1684 	return 0;
1685 }
1686 #endif
1687 static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1688 {
1689 	return set_cpus_allowed_ptr(p, &new_mask);
1690 }
1691 
1692 /*
1693  * Architectures can set this to 1 if they have specified
1694  * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
1695  * but then during bootup it turns out that sched_clock()
1696  * is reliable after all:
1697  */
1698 #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1699 extern int sched_clock_stable;
1700 #endif
1701 
1702 extern unsigned long long sched_clock(void);
1703 
1704 extern void sched_clock_init(void);
1705 extern u64 sched_clock_cpu(int cpu);
1706 
1707 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1708 static inline void sched_clock_tick(void)
1709 {
1710 }
1711 
1712 static inline void sched_clock_idle_sleep_event(void)
1713 {
1714 }
1715 
1716 static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
1717 {
1718 }
1719 #else
1720 extern void sched_clock_tick(void);
1721 extern void sched_clock_idle_sleep_event(void);
1722 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1723 #endif
1724 
1725 /*
1726  * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
1727  * clock constructed from sched_clock():
1728  */
1729 extern unsigned long long cpu_clock(int cpu);
1730 
1731 extern unsigned long long
1732 task_sched_runtime(struct task_struct *task);
1733 extern unsigned long long thread_group_sched_runtime(struct task_struct *task);
1734 
1735 /* sched_exec is called by processes performing an exec */
1736 #ifdef CONFIG_SMP
1737 extern void sched_exec(void);
1738 #else
1739 #define sched_exec()   {}
1740 #endif
1741 
1742 extern void sched_clock_idle_sleep_event(void);
1743 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1744 
1745 #ifdef CONFIG_HOTPLUG_CPU
1746 extern void idle_task_exit(void);
1747 #else
1748 static inline void idle_task_exit(void) {}
1749 #endif
1750 
1751 extern void sched_idle_next(void);
1752 
1753 #if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
1754 extern void wake_up_idle_cpu(int cpu);
1755 #else
1756 static inline void wake_up_idle_cpu(int cpu) { }
1757 #endif
1758 
1759 extern unsigned int sysctl_sched_latency;
1760 extern unsigned int sysctl_sched_min_granularity;
1761 extern unsigned int sysctl_sched_wakeup_granularity;
1762 extern unsigned int sysctl_sched_shares_ratelimit;
1763 extern unsigned int sysctl_sched_shares_thresh;
1764 #ifdef CONFIG_SCHED_DEBUG
1765 extern unsigned int sysctl_sched_child_runs_first;
1766 extern unsigned int sysctl_sched_features;
1767 extern unsigned int sysctl_sched_migration_cost;
1768 extern unsigned int sysctl_sched_nr_migrate;
1769 
1770 int sched_nr_latency_handler(struct ctl_table *table, int write,
1771 		struct file *file, void __user *buffer, size_t *length,
1772 		loff_t *ppos);
1773 #endif
1774 extern unsigned int sysctl_sched_rt_period;
1775 extern int sysctl_sched_rt_runtime;
1776 
1777 int sched_rt_handler(struct ctl_table *table, int write,
1778 		struct file *filp, void __user *buffer, size_t *lenp,
1779 		loff_t *ppos);
1780 
1781 extern unsigned int sysctl_sched_compat_yield;
1782 
1783 #ifdef CONFIG_RT_MUTEXES
1784 extern int rt_mutex_getprio(struct task_struct *p);
1785 extern void rt_mutex_setprio(struct task_struct *p, int prio);
1786 extern void rt_mutex_adjust_pi(struct task_struct *p);
1787 #else
1788 static inline int rt_mutex_getprio(struct task_struct *p)
1789 {
1790 	return p->normal_prio;
1791 }
1792 # define rt_mutex_adjust_pi(p)		do { } while (0)
1793 #endif
1794 
1795 extern void set_user_nice(struct task_struct *p, long nice);
1796 extern int task_prio(const struct task_struct *p);
1797 extern int task_nice(const struct task_struct *p);
1798 extern int can_nice(const struct task_struct *p, const int nice);
1799 extern int task_curr(const struct task_struct *p);
1800 extern int idle_cpu(int cpu);
1801 extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1802 extern int sched_setscheduler_nocheck(struct task_struct *, int,
1803 				      struct sched_param *);
1804 extern struct task_struct *idle_task(int cpu);
1805 extern struct task_struct *curr_task(int cpu);
1806 extern void set_curr_task(int cpu, struct task_struct *p);
1807 
1808 void yield(void);
1809 
1810 /*
1811  * The default (Linux) execution domain.
1812  */
1813 extern struct exec_domain	default_exec_domain;
1814 
1815 union thread_union {
1816 	struct thread_info thread_info;
1817 	unsigned long stack[THREAD_SIZE/sizeof(long)];
1818 };
1819 
1820 #ifndef __HAVE_ARCH_KSTACK_END
1821 static inline int kstack_end(void *addr)
1822 {
1823 	/* Reliable end of stack detection:
1824 	 * Some APM bios versions misalign the stack
1825 	 */
1826 	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1827 }
1828 #endif
1829 
1830 extern union thread_union init_thread_union;
1831 extern struct task_struct init_task;
1832 
1833 extern struct   mm_struct init_mm;
1834 
1835 extern struct pid_namespace init_pid_ns;
1836 
1837 /*
1838  * find a task by one of its numerical ids
1839  *
1840  * find_task_by_pid_type_ns():
1841  *      it is the most generic call - it finds a task by all id,
1842  *      type and namespace specified
1843  * find_task_by_pid_ns():
1844  *      finds a task by its pid in the specified namespace
1845  * find_task_by_vpid():
1846  *      finds a task by its virtual pid
1847  *
1848  * see also find_vpid() etc in include/linux/pid.h
1849  */
1850 
1851 extern struct task_struct *find_task_by_pid_type_ns(int type, int pid,
1852 		struct pid_namespace *ns);
1853 
1854 extern struct task_struct *find_task_by_vpid(pid_t nr);
1855 extern struct task_struct *find_task_by_pid_ns(pid_t nr,
1856 		struct pid_namespace *ns);
1857 
1858 extern void __set_special_pids(struct pid *pid);
1859 
1860 /* per-UID process charging. */
1861 extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
1862 static inline struct user_struct *get_uid(struct user_struct *u)
1863 {
1864 	atomic_inc(&u->__count);
1865 	return u;
1866 }
1867 extern void free_uid(struct user_struct *);
1868 extern void release_uids(struct user_namespace *ns);
1869 
1870 #include <asm/current.h>
1871 
1872 extern void do_timer(unsigned long ticks);
1873 
1874 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1875 extern int wake_up_process(struct task_struct *tsk);
1876 extern void wake_up_new_task(struct task_struct *tsk,
1877 				unsigned long clone_flags);
1878 #ifdef CONFIG_SMP
1879  extern void kick_process(struct task_struct *tsk);
1880 #else
1881  static inline void kick_process(struct task_struct *tsk) { }
1882 #endif
1883 extern void sched_fork(struct task_struct *p, int clone_flags);
1884 extern void sched_dead(struct task_struct *p);
1885 
1886 extern void proc_caches_init(void);
1887 extern void flush_signals(struct task_struct *);
1888 extern void ignore_signals(struct task_struct *);
1889 extern void flush_signal_handlers(struct task_struct *, int force_default);
1890 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1891 
1892 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1893 {
1894 	unsigned long flags;
1895 	int ret;
1896 
1897 	spin_lock_irqsave(&tsk->sighand->siglock, flags);
1898 	ret = dequeue_signal(tsk, mask, info);
1899 	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1900 
1901 	return ret;
1902 }
1903 
1904 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1905 			      sigset_t *mask);
1906 extern void unblock_all_signals(void);
1907 extern void release_task(struct task_struct * p);
1908 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1909 extern int force_sigsegv(int, struct task_struct *);
1910 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1911 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1912 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
1913 extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
1914 extern int kill_pgrp(struct pid *pid, int sig, int priv);
1915 extern int kill_pid(struct pid *pid, int sig, int priv);
1916 extern int kill_proc_info(int, struct siginfo *, pid_t);
1917 extern int do_notify_parent(struct task_struct *, int);
1918 extern void force_sig(int, struct task_struct *);
1919 extern void force_sig_specific(int, struct task_struct *);
1920 extern int send_sig(int, struct task_struct *, int);
1921 extern void zap_other_threads(struct task_struct *p);
1922 extern struct sigqueue *sigqueue_alloc(void);
1923 extern void sigqueue_free(struct sigqueue *);
1924 extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
1925 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
1926 extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1927 
1928 static inline int kill_cad_pid(int sig, int priv)
1929 {
1930 	return kill_pid(cad_pid, sig, priv);
1931 }
1932 
1933 /* These can be the second arg to send_sig_info/send_group_sig_info.  */
1934 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
1935 #define SEND_SIG_PRIV	((struct siginfo *) 1)
1936 #define SEND_SIG_FORCED	((struct siginfo *) 2)
1937 
1938 static inline int is_si_special(const struct siginfo *info)
1939 {
1940 	return info <= SEND_SIG_FORCED;
1941 }
1942 
1943 /* True if we are on the alternate signal stack.  */
1944 
1945 static inline int on_sig_stack(unsigned long sp)
1946 {
1947 	return (sp - current->sas_ss_sp < current->sas_ss_size);
1948 }
1949 
1950 static inline int sas_ss_flags(unsigned long sp)
1951 {
1952 	return (current->sas_ss_size == 0 ? SS_DISABLE
1953 		: on_sig_stack(sp) ? SS_ONSTACK : 0);
1954 }
1955 
1956 /*
1957  * Routines for handling mm_structs
1958  */
1959 extern struct mm_struct * mm_alloc(void);
1960 
1961 /* mmdrop drops the mm and the page tables */
1962 extern void __mmdrop(struct mm_struct *);
1963 static inline void mmdrop(struct mm_struct * mm)
1964 {
1965 	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
1966 		__mmdrop(mm);
1967 }
1968 
1969 /* mmput gets rid of the mappings and all user-space */
1970 extern void mmput(struct mm_struct *);
1971 /* Grab a reference to a task's mm, if it is not already going away */
1972 extern struct mm_struct *get_task_mm(struct task_struct *task);
1973 /* Remove the current tasks stale references to the old mm_struct */
1974 extern void mm_release(struct task_struct *, struct mm_struct *);
1975 /* Allocate a new mm structure and copy contents from tsk->mm */
1976 extern struct mm_struct *dup_mm(struct task_struct *tsk);
1977 
1978 extern int copy_thread(unsigned long, unsigned long, unsigned long,
1979 			struct task_struct *, struct pt_regs *);
1980 extern void flush_thread(void);
1981 extern void exit_thread(void);
1982 
1983 extern void exit_files(struct task_struct *);
1984 extern void __cleanup_signal(struct signal_struct *);
1985 extern void __cleanup_sighand(struct sighand_struct *);
1986 
1987 extern void exit_itimers(struct signal_struct *);
1988 extern void flush_itimer_signals(void);
1989 
1990 extern NORET_TYPE void do_group_exit(int);
1991 
1992 extern void daemonize(const char *, ...);
1993 extern int allow_signal(int);
1994 extern int disallow_signal(int);
1995 
1996 extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1997 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1998 struct task_struct *fork_idle(int);
1999 
2000 extern void set_task_comm(struct task_struct *tsk, char *from);
2001 extern char *get_task_comm(char *to, struct task_struct *tsk);
2002 
2003 #ifdef CONFIG_SMP
2004 extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2005 #else
2006 static inline unsigned long wait_task_inactive(struct task_struct *p,
2007 					       long match_state)
2008 {
2009 	return 1;
2010 }
2011 #endif
2012 
2013 #define next_task(p)	list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
2014 
2015 #define for_each_process(p) \
2016 	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2017 
2018 extern bool is_single_threaded(struct task_struct *);
2019 
2020 /*
2021  * Careful: do_each_thread/while_each_thread is a double loop so
2022  *          'break' will not work as expected - use goto instead.
2023  */
2024 #define do_each_thread(g, t) \
2025 	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2026 
2027 #define while_each_thread(g, t) \
2028 	while ((t = next_thread(t)) != g)
2029 
2030 /* de_thread depends on thread_group_leader not being a pid based check */
2031 #define thread_group_leader(p)	(p == p->group_leader)
2032 
2033 /* Do to the insanities of de_thread it is possible for a process
2034  * to have the pid of the thread group leader without actually being
2035  * the thread group leader.  For iteration through the pids in proc
2036  * all we care about is that we have a task with the appropriate
2037  * pid, we don't actually care if we have the right task.
2038  */
2039 static inline int has_group_leader_pid(struct task_struct *p)
2040 {
2041 	return p->pid == p->tgid;
2042 }
2043 
2044 static inline
2045 int same_thread_group(struct task_struct *p1, struct task_struct *p2)
2046 {
2047 	return p1->tgid == p2->tgid;
2048 }
2049 
2050 static inline struct task_struct *next_thread(const struct task_struct *p)
2051 {
2052 	return list_entry(rcu_dereference(p->thread_group.next),
2053 			  struct task_struct, thread_group);
2054 }
2055 
2056 static inline int thread_group_empty(struct task_struct *p)
2057 {
2058 	return list_empty(&p->thread_group);
2059 }
2060 
2061 #define delay_group_leader(p) \
2062 		(thread_group_leader(p) && !thread_group_empty(p))
2063 
2064 static inline int task_detached(struct task_struct *p)
2065 {
2066 	return p->exit_signal == -1;
2067 }
2068 
2069 /*
2070  * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2071  * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2072  * pins the final release of task.io_context.  Also protects ->cpuset and
2073  * ->cgroup.subsys[].
2074  *
2075  * Nests both inside and outside of read_lock(&tasklist_lock).
2076  * It must not be nested with write_lock_irq(&tasklist_lock),
2077  * neither inside nor outside.
2078  */
2079 static inline void task_lock(struct task_struct *p)
2080 {
2081 	spin_lock(&p->alloc_lock);
2082 }
2083 
2084 static inline void task_unlock(struct task_struct *p)
2085 {
2086 	spin_unlock(&p->alloc_lock);
2087 }
2088 
2089 extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2090 							unsigned long *flags);
2091 
2092 static inline void unlock_task_sighand(struct task_struct *tsk,
2093 						unsigned long *flags)
2094 {
2095 	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2096 }
2097 
2098 #ifndef __HAVE_THREAD_FUNCTIONS
2099 
2100 #define task_thread_info(task)	((struct thread_info *)(task)->stack)
2101 #define task_stack_page(task)	((task)->stack)
2102 
2103 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2104 {
2105 	*task_thread_info(p) = *task_thread_info(org);
2106 	task_thread_info(p)->task = p;
2107 }
2108 
2109 static inline unsigned long *end_of_stack(struct task_struct *p)
2110 {
2111 	return (unsigned long *)(task_thread_info(p) + 1);
2112 }
2113 
2114 #endif
2115 
2116 static inline int object_is_on_stack(void *obj)
2117 {
2118 	void *stack = task_stack_page(current);
2119 
2120 	return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2121 }
2122 
2123 extern void thread_info_cache_init(void);
2124 
2125 #ifdef CONFIG_DEBUG_STACK_USAGE
2126 static inline unsigned long stack_not_used(struct task_struct *p)
2127 {
2128 	unsigned long *n = end_of_stack(p);
2129 
2130 	do { 	/* Skip over canary */
2131 		n++;
2132 	} while (!*n);
2133 
2134 	return (unsigned long)n - (unsigned long)end_of_stack(p);
2135 }
2136 #endif
2137 
2138 /* set thread flags in other task's structures
2139  * - see asm/thread_info.h for TIF_xxxx flags available
2140  */
2141 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2142 {
2143 	set_ti_thread_flag(task_thread_info(tsk), flag);
2144 }
2145 
2146 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2147 {
2148 	clear_ti_thread_flag(task_thread_info(tsk), flag);
2149 }
2150 
2151 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2152 {
2153 	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2154 }
2155 
2156 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2157 {
2158 	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2159 }
2160 
2161 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2162 {
2163 	return test_ti_thread_flag(task_thread_info(tsk), flag);
2164 }
2165 
2166 static inline void set_tsk_need_resched(struct task_struct *tsk)
2167 {
2168 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2169 }
2170 
2171 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2172 {
2173 	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2174 }
2175 
2176 static inline int test_tsk_need_resched(struct task_struct *tsk)
2177 {
2178 	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2179 }
2180 
2181 static inline int signal_pending(struct task_struct *p)
2182 {
2183 	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2184 }
2185 
2186 extern int __fatal_signal_pending(struct task_struct *p);
2187 
2188 static inline int fatal_signal_pending(struct task_struct *p)
2189 {
2190 	return signal_pending(p) && __fatal_signal_pending(p);
2191 }
2192 
2193 static inline int signal_pending_state(long state, struct task_struct *p)
2194 {
2195 	if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2196 		return 0;
2197 	if (!signal_pending(p))
2198 		return 0;
2199 
2200 	return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2201 }
2202 
2203 static inline int need_resched(void)
2204 {
2205 	return unlikely(test_thread_flag(TIF_NEED_RESCHED));
2206 }
2207 
2208 /*
2209  * cond_resched() and cond_resched_lock(): latency reduction via
2210  * explicit rescheduling in places that are safe. The return
2211  * value indicates whether a reschedule was done in fact.
2212  * cond_resched_lock() will drop the spinlock before scheduling,
2213  * cond_resched_softirq() will enable bhs before scheduling.
2214  */
2215 extern int _cond_resched(void);
2216 #ifdef CONFIG_PREEMPT_BKL
2217 static inline int cond_resched(void)
2218 {
2219 	return 0;
2220 }
2221 #else
2222 static inline int cond_resched(void)
2223 {
2224 	return _cond_resched();
2225 }
2226 #endif
2227 extern int cond_resched_lock(spinlock_t * lock);
2228 extern int cond_resched_softirq(void);
2229 static inline int cond_resched_bkl(void)
2230 {
2231 	return _cond_resched();
2232 }
2233 
2234 /*
2235  * Does a critical section need to be broken due to another
2236  * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2237  * but a general need for low latency)
2238  */
2239 static inline int spin_needbreak(spinlock_t *lock)
2240 {
2241 #ifdef CONFIG_PREEMPT
2242 	return spin_is_contended(lock);
2243 #else
2244 	return 0;
2245 #endif
2246 }
2247 
2248 /*
2249  * Thread group CPU time accounting.
2250  */
2251 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2252 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2253 
2254 static inline void thread_group_cputime_init(struct signal_struct *sig)
2255 {
2256 	sig->cputimer.cputime = INIT_CPUTIME;
2257 	spin_lock_init(&sig->cputimer.lock);
2258 	sig->cputimer.running = 0;
2259 }
2260 
2261 static inline void thread_group_cputime_free(struct signal_struct *sig)
2262 {
2263 }
2264 
2265 /*
2266  * Reevaluate whether the task has signals pending delivery.
2267  * Wake the task if so.
2268  * This is required every time the blocked sigset_t changes.
2269  * callers must hold sighand->siglock.
2270  */
2271 extern void recalc_sigpending_and_wake(struct task_struct *t);
2272 extern void recalc_sigpending(void);
2273 
2274 extern void signal_wake_up(struct task_struct *t, int resume_stopped);
2275 
2276 /*
2277  * Wrappers for p->thread_info->cpu access. No-op on UP.
2278  */
2279 #ifdef CONFIG_SMP
2280 
2281 static inline unsigned int task_cpu(const struct task_struct *p)
2282 {
2283 	return task_thread_info(p)->cpu;
2284 }
2285 
2286 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2287 
2288 #else
2289 
2290 static inline unsigned int task_cpu(const struct task_struct *p)
2291 {
2292 	return 0;
2293 }
2294 
2295 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2296 {
2297 }
2298 
2299 #endif /* CONFIG_SMP */
2300 
2301 extern void arch_pick_mmap_layout(struct mm_struct *mm);
2302 
2303 #ifdef CONFIG_TRACING
2304 extern void
2305 __trace_special(void *__tr, void *__data,
2306 		unsigned long arg1, unsigned long arg2, unsigned long arg3);
2307 #else
2308 static inline void
2309 __trace_special(void *__tr, void *__data,
2310 		unsigned long arg1, unsigned long arg2, unsigned long arg3)
2311 {
2312 }
2313 #endif
2314 
2315 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2316 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2317 
2318 extern void normalize_rt_tasks(void);
2319 
2320 #ifdef CONFIG_GROUP_SCHED
2321 
2322 extern struct task_group init_task_group;
2323 #ifdef CONFIG_USER_SCHED
2324 extern struct task_group root_task_group;
2325 extern void set_tg_uid(struct user_struct *user);
2326 #endif
2327 
2328 extern struct task_group *sched_create_group(struct task_group *parent);
2329 extern void sched_destroy_group(struct task_group *tg);
2330 extern void sched_move_task(struct task_struct *tsk);
2331 #ifdef CONFIG_FAIR_GROUP_SCHED
2332 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2333 extern unsigned long sched_group_shares(struct task_group *tg);
2334 #endif
2335 #ifdef CONFIG_RT_GROUP_SCHED
2336 extern int sched_group_set_rt_runtime(struct task_group *tg,
2337 				      long rt_runtime_us);
2338 extern long sched_group_rt_runtime(struct task_group *tg);
2339 extern int sched_group_set_rt_period(struct task_group *tg,
2340 				      long rt_period_us);
2341 extern long sched_group_rt_period(struct task_group *tg);
2342 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
2343 #endif
2344 #endif
2345 
2346 extern int task_can_switch_user(struct user_struct *up,
2347 					struct task_struct *tsk);
2348 
2349 #ifdef CONFIG_TASK_XACCT
2350 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2351 {
2352 	tsk->ioac.rchar += amt;
2353 }
2354 
2355 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2356 {
2357 	tsk->ioac.wchar += amt;
2358 }
2359 
2360 static inline void inc_syscr(struct task_struct *tsk)
2361 {
2362 	tsk->ioac.syscr++;
2363 }
2364 
2365 static inline void inc_syscw(struct task_struct *tsk)
2366 {
2367 	tsk->ioac.syscw++;
2368 }
2369 #else
2370 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2371 {
2372 }
2373 
2374 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2375 {
2376 }
2377 
2378 static inline void inc_syscr(struct task_struct *tsk)
2379 {
2380 }
2381 
2382 static inline void inc_syscw(struct task_struct *tsk)
2383 {
2384 }
2385 #endif
2386 
2387 #ifndef TASK_SIZE_OF
2388 #define TASK_SIZE_OF(tsk)	TASK_SIZE
2389 #endif
2390 
2391 #ifdef CONFIG_MM_OWNER
2392 extern void mm_update_next_owner(struct mm_struct *mm);
2393 extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2394 #else
2395 static inline void mm_update_next_owner(struct mm_struct *mm)
2396 {
2397 }
2398 
2399 static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2400 {
2401 }
2402 #endif /* CONFIG_MM_OWNER */
2403 
2404 #define TASK_STATE_TO_CHAR_STR "RSDTtZX"
2405 
2406 #endif /* __KERNEL__ */
2407 
2408 #endif
2409