xref: /linux/include/linux/sched.h (revision f7511d5f66f01fc451747b24e79f3ada7a3af9af)
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/fs_struct.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 
91 #include <asm/processor.h>
92 
93 struct mem_cgroup;
94 struct exec_domain;
95 struct futex_pi_state;
96 struct robust_list_head;
97 struct bio;
98 
99 /*
100  * List of flags we want to share for kernel threads,
101  * if only because they are not used by them anyway.
102  */
103 #define CLONE_KERNEL	(CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
104 
105 /*
106  * These are the constant used to fake the fixed-point load-average
107  * counting. Some notes:
108  *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
109  *    a load-average precision of 10 bits integer + 11 bits fractional
110  *  - if you want to count load-averages more often, you need more
111  *    precision, or rounding will get you. With 2-second counting freq,
112  *    the EXP_n values would be 1981, 2034 and 2043 if still using only
113  *    11 bit fractions.
114  */
115 extern unsigned long avenrun[];		/* Load averages */
116 
117 #define FSHIFT		11		/* nr of bits of precision */
118 #define FIXED_1		(1<<FSHIFT)	/* 1.0 as fixed-point */
119 #define LOAD_FREQ	(5*HZ+1)	/* 5 sec intervals */
120 #define EXP_1		1884		/* 1/exp(5sec/1min) as fixed-point */
121 #define EXP_5		2014		/* 1/exp(5sec/5min) */
122 #define EXP_15		2037		/* 1/exp(5sec/15min) */
123 
124 #define CALC_LOAD(load,exp,n) \
125 	load *= exp; \
126 	load += n*(FIXED_1-exp); \
127 	load >>= FSHIFT;
128 
129 extern unsigned long total_forks;
130 extern int nr_threads;
131 DECLARE_PER_CPU(unsigned long, process_counts);
132 extern int nr_processes(void);
133 extern unsigned long nr_running(void);
134 extern unsigned long nr_uninterruptible(void);
135 extern unsigned long nr_active(void);
136 extern unsigned long nr_iowait(void);
137 extern unsigned long weighted_cpuload(const int cpu);
138 
139 struct seq_file;
140 struct cfs_rq;
141 struct task_group;
142 #ifdef CONFIG_SCHED_DEBUG
143 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
144 extern void proc_sched_set_task(struct task_struct *p);
145 extern void
146 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
147 #else
148 static inline void
149 proc_sched_show_task(struct task_struct *p, struct seq_file *m)
150 {
151 }
152 static inline void proc_sched_set_task(struct task_struct *p)
153 {
154 }
155 static inline void
156 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
157 {
158 }
159 #endif
160 
161 /*
162  * Task state bitmask. NOTE! These bits are also
163  * encoded in fs/proc/array.c: get_task_state().
164  *
165  * We have two separate sets of flags: task->state
166  * is about runnability, while task->exit_state are
167  * about the task exiting. Confusing, but this way
168  * modifying one set can't modify the other one by
169  * mistake.
170  */
171 #define TASK_RUNNING		0
172 #define TASK_INTERRUPTIBLE	1
173 #define TASK_UNINTERRUPTIBLE	2
174 #define __TASK_STOPPED		4
175 #define __TASK_TRACED		8
176 /* in tsk->exit_state */
177 #define EXIT_ZOMBIE		16
178 #define EXIT_DEAD		32
179 /* in tsk->state again */
180 #define TASK_DEAD		64
181 #define TASK_WAKEKILL		128
182 
183 /* Convenience macros for the sake of set_task_state */
184 #define TASK_KILLABLE		(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
185 #define TASK_STOPPED		(TASK_WAKEKILL | __TASK_STOPPED)
186 #define TASK_TRACED		(TASK_WAKEKILL | __TASK_TRACED)
187 
188 /* Convenience macros for the sake of wake_up */
189 #define TASK_NORMAL		(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
190 #define TASK_ALL		(TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
191 
192 /* get_task_state() */
193 #define TASK_REPORT		(TASK_RUNNING | TASK_INTERRUPTIBLE | \
194 				 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
195 				 __TASK_TRACED)
196 
197 #define task_is_traced(task)	((task->state & __TASK_TRACED) != 0)
198 #define task_is_stopped(task)	((task->state & __TASK_STOPPED) != 0)
199 #define task_is_stopped_or_traced(task)	\
200 			((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
201 #define task_contributes_to_load(task)	\
202 				((task->state & TASK_UNINTERRUPTIBLE) != 0)
203 
204 #define __set_task_state(tsk, state_value)		\
205 	do { (tsk)->state = (state_value); } while (0)
206 #define set_task_state(tsk, state_value)		\
207 	set_mb((tsk)->state, (state_value))
208 
209 /*
210  * set_current_state() includes a barrier so that the write of current->state
211  * is correctly serialised wrt the caller's subsequent test of whether to
212  * actually sleep:
213  *
214  *	set_current_state(TASK_UNINTERRUPTIBLE);
215  *	if (do_i_need_to_sleep())
216  *		schedule();
217  *
218  * If the caller does not need such serialisation then use __set_current_state()
219  */
220 #define __set_current_state(state_value)			\
221 	do { current->state = (state_value); } while (0)
222 #define set_current_state(state_value)		\
223 	set_mb(current->state, (state_value))
224 
225 /* Task command name length */
226 #define TASK_COMM_LEN 16
227 
228 #include <linux/spinlock.h>
229 
230 /*
231  * This serializes "schedule()" and also protects
232  * the run-queue from deletions/modifications (but
233  * _adding_ to the beginning of the run-queue has
234  * a separate lock).
235  */
236 extern rwlock_t tasklist_lock;
237 extern spinlock_t mmlist_lock;
238 
239 struct task_struct;
240 
241 extern void sched_init(void);
242 extern void sched_init_smp(void);
243 extern asmlinkage void schedule_tail(struct task_struct *prev);
244 extern void init_idle(struct task_struct *idle, int cpu);
245 extern void init_idle_bootup_task(struct task_struct *idle);
246 
247 extern cpumask_t nohz_cpu_mask;
248 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
249 extern int select_nohz_load_balancer(int cpu);
250 #else
251 static inline int select_nohz_load_balancer(int cpu)
252 {
253 	return 0;
254 }
255 #endif
256 
257 extern unsigned long rt_needs_cpu(int cpu);
258 
259 /*
260  * Only dump TASK_* tasks. (0 for all tasks)
261  */
262 extern void show_state_filter(unsigned long state_filter);
263 
264 static inline void show_state(void)
265 {
266 	show_state_filter(0);
267 }
268 
269 extern void show_regs(struct pt_regs *);
270 
271 /*
272  * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
273  * task), SP is the stack pointer of the first frame that should be shown in the back
274  * trace (or NULL if the entire call-chain of the task should be shown).
275  */
276 extern void show_stack(struct task_struct *task, unsigned long *sp);
277 
278 void io_schedule(void);
279 long io_schedule_timeout(long timeout);
280 
281 extern void cpu_init (void);
282 extern void trap_init(void);
283 extern void account_process_tick(struct task_struct *task, int user);
284 extern void update_process_times(int user);
285 extern void scheduler_tick(void);
286 extern void hrtick_resched(void);
287 
288 extern void sched_show_task(struct task_struct *p);
289 
290 #ifdef CONFIG_DETECT_SOFTLOCKUP
291 extern void softlockup_tick(void);
292 extern void spawn_softlockup_task(void);
293 extern void touch_softlockup_watchdog(void);
294 extern void touch_all_softlockup_watchdogs(void);
295 extern unsigned long  softlockup_thresh;
296 extern unsigned long sysctl_hung_task_check_count;
297 extern unsigned long sysctl_hung_task_timeout_secs;
298 extern unsigned long sysctl_hung_task_warnings;
299 #else
300 static inline void softlockup_tick(void)
301 {
302 }
303 static inline void spawn_softlockup_task(void)
304 {
305 }
306 static inline void touch_softlockup_watchdog(void)
307 {
308 }
309 static inline void touch_all_softlockup_watchdogs(void)
310 {
311 }
312 #endif
313 
314 
315 /* Attach to any functions which should be ignored in wchan output. */
316 #define __sched		__attribute__((__section__(".sched.text")))
317 
318 /* Linker adds these: start and end of __sched functions */
319 extern char __sched_text_start[], __sched_text_end[];
320 
321 /* Is this address in the __sched functions? */
322 extern int in_sched_functions(unsigned long addr);
323 
324 #define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
325 extern signed long schedule_timeout(signed long timeout);
326 extern signed long schedule_timeout_interruptible(signed long timeout);
327 extern signed long schedule_timeout_killable(signed long timeout);
328 extern signed long schedule_timeout_uninterruptible(signed long timeout);
329 asmlinkage void schedule(void);
330 
331 struct nsproxy;
332 struct user_namespace;
333 
334 /* Maximum number of active map areas.. This is a random (large) number */
335 #define DEFAULT_MAX_MAP_COUNT	65536
336 
337 extern int sysctl_max_map_count;
338 
339 #include <linux/aio.h>
340 
341 extern unsigned long
342 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
343 		       unsigned long, unsigned long);
344 extern unsigned long
345 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
346 			  unsigned long len, unsigned long pgoff,
347 			  unsigned long flags);
348 extern void arch_unmap_area(struct mm_struct *, unsigned long);
349 extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
350 
351 #if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
352 /*
353  * The mm counters are not protected by its page_table_lock,
354  * so must be incremented atomically.
355  */
356 #define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
357 #define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
358 #define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
359 #define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
360 #define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
361 
362 #else  /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
363 /*
364  * The mm counters are protected by its page_table_lock,
365  * so can be incremented directly.
366  */
367 #define set_mm_counter(mm, member, value) (mm)->_##member = (value)
368 #define get_mm_counter(mm, member) ((mm)->_##member)
369 #define add_mm_counter(mm, member, value) (mm)->_##member += (value)
370 #define inc_mm_counter(mm, member) (mm)->_##member++
371 #define dec_mm_counter(mm, member) (mm)->_##member--
372 
373 #endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
374 
375 #define get_mm_rss(mm)					\
376 	(get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
377 #define update_hiwater_rss(mm)	do {			\
378 	unsigned long _rss = get_mm_rss(mm);		\
379 	if ((mm)->hiwater_rss < _rss)			\
380 		(mm)->hiwater_rss = _rss;		\
381 } while (0)
382 #define update_hiwater_vm(mm)	do {			\
383 	if ((mm)->hiwater_vm < (mm)->total_vm)		\
384 		(mm)->hiwater_vm = (mm)->total_vm;	\
385 } while (0)
386 
387 extern void set_dumpable(struct mm_struct *mm, int value);
388 extern int get_dumpable(struct mm_struct *mm);
389 
390 /* mm flags */
391 /* dumpable bits */
392 #define MMF_DUMPABLE      0  /* core dump is permitted */
393 #define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
394 #define MMF_DUMPABLE_BITS 2
395 
396 /* coredump filter bits */
397 #define MMF_DUMP_ANON_PRIVATE	2
398 #define MMF_DUMP_ANON_SHARED	3
399 #define MMF_DUMP_MAPPED_PRIVATE	4
400 #define MMF_DUMP_MAPPED_SHARED	5
401 #define MMF_DUMP_ELF_HEADERS	6
402 #define MMF_DUMP_FILTER_SHIFT	MMF_DUMPABLE_BITS
403 #define MMF_DUMP_FILTER_BITS	5
404 #define MMF_DUMP_FILTER_MASK \
405 	(((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
406 #define MMF_DUMP_FILTER_DEFAULT \
407 	((1 << MMF_DUMP_ANON_PRIVATE) |	(1 << MMF_DUMP_ANON_SHARED))
408 
409 struct sighand_struct {
410 	atomic_t		count;
411 	struct k_sigaction	action[_NSIG];
412 	spinlock_t		siglock;
413 	wait_queue_head_t	signalfd_wqh;
414 };
415 
416 struct pacct_struct {
417 	int			ac_flag;
418 	long			ac_exitcode;
419 	unsigned long		ac_mem;
420 	cputime_t		ac_utime, ac_stime;
421 	unsigned long		ac_minflt, ac_majflt;
422 };
423 
424 /*
425  * NOTE! "signal_struct" does not have it's own
426  * locking, because a shared signal_struct always
427  * implies a shared sighand_struct, so locking
428  * sighand_struct is always a proper superset of
429  * the locking of signal_struct.
430  */
431 struct signal_struct {
432 	atomic_t		count;
433 	atomic_t		live;
434 
435 	wait_queue_head_t	wait_chldexit;	/* for wait4() */
436 
437 	/* current thread group signal load-balancing target: */
438 	struct task_struct	*curr_target;
439 
440 	/* shared signal handling: */
441 	struct sigpending	shared_pending;
442 
443 	/* thread group exit support */
444 	int			group_exit_code;
445 	/* overloaded:
446 	 * - notify group_exit_task when ->count is equal to notify_count
447 	 * - everyone except group_exit_task is stopped during signal delivery
448 	 *   of fatal signals, group_exit_task processes the signal.
449 	 */
450 	struct task_struct	*group_exit_task;
451 	int			notify_count;
452 
453 	/* thread group stop support, overloads group_exit_code too */
454 	int			group_stop_count;
455 	unsigned int		flags; /* see SIGNAL_* flags below */
456 
457 	/* POSIX.1b Interval Timers */
458 	struct list_head posix_timers;
459 
460 	/* ITIMER_REAL timer for the process */
461 	struct hrtimer real_timer;
462 	struct pid *leader_pid;
463 	ktime_t it_real_incr;
464 
465 	/* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
466 	cputime_t it_prof_expires, it_virt_expires;
467 	cputime_t it_prof_incr, it_virt_incr;
468 
469 	/* job control IDs */
470 
471 	/*
472 	 * pgrp and session fields are deprecated.
473 	 * use the task_session_Xnr and task_pgrp_Xnr routines below
474 	 */
475 
476 	union {
477 		pid_t pgrp __deprecated;
478 		pid_t __pgrp;
479 	};
480 
481 	struct pid *tty_old_pgrp;
482 
483 	union {
484 		pid_t session __deprecated;
485 		pid_t __session;
486 	};
487 
488 	/* boolean value for session group leader */
489 	int leader;
490 
491 	struct tty_struct *tty; /* NULL if no tty */
492 
493 	/*
494 	 * Cumulative resource counters for dead threads in the group,
495 	 * and for reaped dead child processes forked by this group.
496 	 * Live threads maintain their own counters and add to these
497 	 * in __exit_signal, except for the group leader.
498 	 */
499 	cputime_t utime, stime, cutime, cstime;
500 	cputime_t gtime;
501 	cputime_t cgtime;
502 	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
503 	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
504 	unsigned long inblock, oublock, cinblock, coublock;
505 
506 	/*
507 	 * Cumulative ns of scheduled CPU time for dead threads in the
508 	 * group, not including a zombie group leader.  (This only differs
509 	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
510 	 * other than jiffies.)
511 	 */
512 	unsigned long long sum_sched_runtime;
513 
514 	/*
515 	 * We don't bother to synchronize most readers of this at all,
516 	 * because there is no reader checking a limit that actually needs
517 	 * to get both rlim_cur and rlim_max atomically, and either one
518 	 * alone is a single word that can safely be read normally.
519 	 * getrlimit/setrlimit use task_lock(current->group_leader) to
520 	 * protect this instead of the siglock, because they really
521 	 * have no need to disable irqs.
522 	 */
523 	struct rlimit rlim[RLIM_NLIMITS];
524 
525 	struct list_head cpu_timers[3];
526 
527 	/* keep the process-shared keyrings here so that they do the right
528 	 * thing in threads created with CLONE_THREAD */
529 #ifdef CONFIG_KEYS
530 	struct key *session_keyring;	/* keyring inherited over fork */
531 	struct key *process_keyring;	/* keyring private to this process */
532 #endif
533 #ifdef CONFIG_BSD_PROCESS_ACCT
534 	struct pacct_struct pacct;	/* per-process accounting information */
535 #endif
536 #ifdef CONFIG_TASKSTATS
537 	struct taskstats *stats;
538 #endif
539 #ifdef CONFIG_AUDIT
540 	unsigned audit_tty;
541 	struct tty_audit_buf *tty_audit_buf;
542 #endif
543 };
544 
545 /* Context switch must be unlocked if interrupts are to be enabled */
546 #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
547 # define __ARCH_WANT_UNLOCKED_CTXSW
548 #endif
549 
550 /*
551  * Bits in flags field of signal_struct.
552  */
553 #define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
554 #define SIGNAL_STOP_DEQUEUED	0x00000002 /* stop signal dequeued */
555 #define SIGNAL_STOP_CONTINUED	0x00000004 /* SIGCONT since WCONTINUED reap */
556 #define SIGNAL_GROUP_EXIT	0x00000008 /* group exit in progress */
557 /*
558  * Pending notifications to parent.
559  */
560 #define SIGNAL_CLD_STOPPED	0x00000010
561 #define SIGNAL_CLD_CONTINUED	0x00000020
562 #define SIGNAL_CLD_MASK		(SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
563 
564 #define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */
565 
566 /* If true, all threads except ->group_exit_task have pending SIGKILL */
567 static inline int signal_group_exit(const struct signal_struct *sig)
568 {
569 	return	(sig->flags & SIGNAL_GROUP_EXIT) ||
570 		(sig->group_exit_task != NULL);
571 }
572 
573 /*
574  * Some day this will be a full-fledged user tracking system..
575  */
576 struct user_struct {
577 	atomic_t __count;	/* reference count */
578 	atomic_t processes;	/* How many processes does this user have? */
579 	atomic_t files;		/* How many open files does this user have? */
580 	atomic_t sigpending;	/* How many pending signals does this user have? */
581 #ifdef CONFIG_INOTIFY_USER
582 	atomic_t inotify_watches; /* How many inotify watches does this user have? */
583 	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
584 #endif
585 #ifdef CONFIG_POSIX_MQUEUE
586 	/* protected by mq_lock	*/
587 	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
588 #endif
589 	unsigned long locked_shm; /* How many pages of mlocked shm ? */
590 
591 #ifdef CONFIG_KEYS
592 	struct key *uid_keyring;	/* UID specific keyring */
593 	struct key *session_keyring;	/* UID's default session keyring */
594 #endif
595 
596 	/* Hash table maintenance information */
597 	struct hlist_node uidhash_node;
598 	uid_t uid;
599 
600 #ifdef CONFIG_USER_SCHED
601 	struct task_group *tg;
602 #ifdef CONFIG_SYSFS
603 	struct kobject kobj;
604 	struct work_struct work;
605 #endif
606 #endif
607 };
608 
609 extern int uids_sysfs_init(void);
610 
611 extern struct user_struct *find_user(uid_t);
612 
613 extern struct user_struct root_user;
614 #define INIT_USER (&root_user)
615 
616 struct backing_dev_info;
617 struct reclaim_state;
618 
619 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
620 struct sched_info {
621 	/* cumulative counters */
622 	unsigned long pcount;	      /* # of times run on this cpu */
623 	unsigned long long cpu_time,  /* time spent on the cpu */
624 			   run_delay; /* time spent waiting on a runqueue */
625 
626 	/* timestamps */
627 	unsigned long long last_arrival,/* when we last ran on a cpu */
628 			   last_queued;	/* when we were last queued to run */
629 #ifdef CONFIG_SCHEDSTATS
630 	/* BKL stats */
631 	unsigned int bkl_count;
632 #endif
633 };
634 #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
635 
636 #ifdef CONFIG_SCHEDSTATS
637 extern const struct file_operations proc_schedstat_operations;
638 #endif /* CONFIG_SCHEDSTATS */
639 
640 #ifdef CONFIG_TASK_DELAY_ACCT
641 struct task_delay_info {
642 	spinlock_t	lock;
643 	unsigned int	flags;	/* Private per-task flags */
644 
645 	/* For each stat XXX, add following, aligned appropriately
646 	 *
647 	 * struct timespec XXX_start, XXX_end;
648 	 * u64 XXX_delay;
649 	 * u32 XXX_count;
650 	 *
651 	 * Atomicity of updates to XXX_delay, XXX_count protected by
652 	 * single lock above (split into XXX_lock if contention is an issue).
653 	 */
654 
655 	/*
656 	 * XXX_count is incremented on every XXX operation, the delay
657 	 * associated with the operation is added to XXX_delay.
658 	 * XXX_delay contains the accumulated delay time in nanoseconds.
659 	 */
660 	struct timespec blkio_start, blkio_end;	/* Shared by blkio, swapin */
661 	u64 blkio_delay;	/* wait for sync block io completion */
662 	u64 swapin_delay;	/* wait for swapin block io completion */
663 	u32 blkio_count;	/* total count of the number of sync block */
664 				/* io operations performed */
665 	u32 swapin_count;	/* total count of the number of swapin block */
666 				/* io operations performed */
667 };
668 #endif	/* CONFIG_TASK_DELAY_ACCT */
669 
670 static inline int sched_info_on(void)
671 {
672 #ifdef CONFIG_SCHEDSTATS
673 	return 1;
674 #elif defined(CONFIG_TASK_DELAY_ACCT)
675 	extern int delayacct_on;
676 	return delayacct_on;
677 #else
678 	return 0;
679 #endif
680 }
681 
682 enum cpu_idle_type {
683 	CPU_IDLE,
684 	CPU_NOT_IDLE,
685 	CPU_NEWLY_IDLE,
686 	CPU_MAX_IDLE_TYPES
687 };
688 
689 /*
690  * sched-domains (multiprocessor balancing) declarations:
691  */
692 
693 /*
694  * Increase resolution of nice-level calculations:
695  */
696 #define SCHED_LOAD_SHIFT	10
697 #define SCHED_LOAD_SCALE	(1L << SCHED_LOAD_SHIFT)
698 
699 #define SCHED_LOAD_SCALE_FUZZ	SCHED_LOAD_SCALE
700 
701 #ifdef CONFIG_SMP
702 #define SD_LOAD_BALANCE		1	/* Do load balancing on this domain. */
703 #define SD_BALANCE_NEWIDLE	2	/* Balance when about to become idle */
704 #define SD_BALANCE_EXEC		4	/* Balance on exec */
705 #define SD_BALANCE_FORK		8	/* Balance on fork, clone */
706 #define SD_WAKE_IDLE		16	/* Wake to idle CPU on task wakeup */
707 #define SD_WAKE_AFFINE		32	/* Wake task to waking CPU */
708 #define SD_WAKE_BALANCE		64	/* Perform balancing at task wakeup */
709 #define SD_SHARE_CPUPOWER	128	/* Domain members share cpu power */
710 #define SD_POWERSAVINGS_BALANCE	256	/* Balance for power savings */
711 #define SD_SHARE_PKG_RESOURCES	512	/* Domain members share cpu pkg resources */
712 #define SD_SERIALIZE		1024	/* Only a single load balancing instance */
713 #define SD_WAKE_IDLE_FAR	2048	/* Gain latency sacrificing cache hit */
714 
715 #define BALANCE_FOR_MC_POWER	\
716 	(sched_smt_power_savings ? SD_POWERSAVINGS_BALANCE : 0)
717 
718 #define BALANCE_FOR_PKG_POWER	\
719 	((sched_mc_power_savings || sched_smt_power_savings) ?	\
720 	 SD_POWERSAVINGS_BALANCE : 0)
721 
722 #define test_sd_parent(sd, flag)	((sd->parent &&		\
723 					 (sd->parent->flags & flag)) ? 1 : 0)
724 
725 
726 struct sched_group {
727 	struct sched_group *next;	/* Must be a circular list */
728 	cpumask_t cpumask;
729 
730 	/*
731 	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
732 	 * single CPU. This is read only (except for setup, hotplug CPU).
733 	 * Note : Never change cpu_power without recompute its reciprocal
734 	 */
735 	unsigned int __cpu_power;
736 	/*
737 	 * reciprocal value of cpu_power to avoid expensive divides
738 	 * (see include/linux/reciprocal_div.h)
739 	 */
740 	u32 reciprocal_cpu_power;
741 };
742 
743 enum sched_domain_level {
744 	SD_LV_NONE = 0,
745 	SD_LV_SIBLING,
746 	SD_LV_MC,
747 	SD_LV_CPU,
748 	SD_LV_NODE,
749 	SD_LV_ALLNODES,
750 	SD_LV_MAX
751 };
752 
753 struct sched_domain_attr {
754 	int relax_domain_level;
755 };
756 
757 #define SD_ATTR_INIT	(struct sched_domain_attr) {	\
758 	.relax_domain_level = -1,			\
759 }
760 
761 struct sched_domain {
762 	/* These fields must be setup */
763 	struct sched_domain *parent;	/* top domain must be null terminated */
764 	struct sched_domain *child;	/* bottom domain must be null terminated */
765 	struct sched_group *groups;	/* the balancing groups of the domain */
766 	cpumask_t span;			/* span of all CPUs in this domain */
767 	int first_cpu;			/* cache of the first cpu in this domain */
768 	unsigned long min_interval;	/* Minimum balance interval ms */
769 	unsigned long max_interval;	/* Maximum balance interval ms */
770 	unsigned int busy_factor;	/* less balancing by factor if busy */
771 	unsigned int imbalance_pct;	/* No balance until over watermark */
772 	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
773 	unsigned int busy_idx;
774 	unsigned int idle_idx;
775 	unsigned int newidle_idx;
776 	unsigned int wake_idx;
777 	unsigned int forkexec_idx;
778 	int flags;			/* See SD_* */
779 	enum sched_domain_level level;
780 
781 	/* Runtime fields. */
782 	unsigned long last_balance;	/* init to jiffies. units in jiffies */
783 	unsigned int balance_interval;	/* initialise to 1. units in ms. */
784 	unsigned int nr_balance_failed; /* initialise to 0 */
785 
786 #ifdef CONFIG_SCHEDSTATS
787 	/* load_balance() stats */
788 	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
789 	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
790 	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
791 	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
792 	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
793 	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
794 	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
795 	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
796 
797 	/* Active load balancing */
798 	unsigned int alb_count;
799 	unsigned int alb_failed;
800 	unsigned int alb_pushed;
801 
802 	/* SD_BALANCE_EXEC stats */
803 	unsigned int sbe_count;
804 	unsigned int sbe_balanced;
805 	unsigned int sbe_pushed;
806 
807 	/* SD_BALANCE_FORK stats */
808 	unsigned int sbf_count;
809 	unsigned int sbf_balanced;
810 	unsigned int sbf_pushed;
811 
812 	/* try_to_wake_up() stats */
813 	unsigned int ttwu_wake_remote;
814 	unsigned int ttwu_move_affine;
815 	unsigned int ttwu_move_balance;
816 #endif
817 };
818 
819 extern void partition_sched_domains(int ndoms_new, cpumask_t *doms_new,
820 				    struct sched_domain_attr *dattr_new);
821 extern int arch_reinit_sched_domains(void);
822 
823 #endif	/* CONFIG_SMP */
824 
825 /*
826  * A runqueue laden with a single nice 0 task scores a weighted_cpuload of
827  * SCHED_LOAD_SCALE. This function returns 1 if any cpu is laden with a
828  * task of nice 0 or enough lower priority tasks to bring up the
829  * weighted_cpuload
830  */
831 static inline int above_background_load(void)
832 {
833 	unsigned long cpu;
834 
835 	for_each_online_cpu(cpu) {
836 		if (weighted_cpuload(cpu) >= SCHED_LOAD_SCALE)
837 			return 1;
838 	}
839 	return 0;
840 }
841 
842 struct io_context;			/* See blkdev.h */
843 #define NGROUPS_SMALL		32
844 #define NGROUPS_PER_BLOCK	((unsigned int)(PAGE_SIZE / sizeof(gid_t)))
845 struct group_info {
846 	int ngroups;
847 	atomic_t usage;
848 	gid_t small_block[NGROUPS_SMALL];
849 	int nblocks;
850 	gid_t *blocks[0];
851 };
852 
853 /*
854  * get_group_info() must be called with the owning task locked (via task_lock())
855  * when task != current.  The reason being that the vast majority of callers are
856  * looking at current->group_info, which can not be changed except by the
857  * current task.  Changing current->group_info requires the task lock, too.
858  */
859 #define get_group_info(group_info) do { \
860 	atomic_inc(&(group_info)->usage); \
861 } while (0)
862 
863 #define put_group_info(group_info) do { \
864 	if (atomic_dec_and_test(&(group_info)->usage)) \
865 		groups_free(group_info); \
866 } while (0)
867 
868 extern struct group_info *groups_alloc(int gidsetsize);
869 extern void groups_free(struct group_info *group_info);
870 extern int set_current_groups(struct group_info *group_info);
871 extern int groups_search(struct group_info *group_info, gid_t grp);
872 /* access the groups "array" with this macro */
873 #define GROUP_AT(gi, i) \
874     ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
875 
876 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
877 extern void prefetch_stack(struct task_struct *t);
878 #else
879 static inline void prefetch_stack(struct task_struct *t) { }
880 #endif
881 
882 struct audit_context;		/* See audit.c */
883 struct mempolicy;
884 struct pipe_inode_info;
885 struct uts_namespace;
886 
887 struct rq;
888 struct sched_domain;
889 
890 struct sched_class {
891 	const struct sched_class *next;
892 
893 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int wakeup);
894 	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int sleep);
895 	void (*yield_task) (struct rq *rq);
896 	int  (*select_task_rq)(struct task_struct *p, int sync);
897 
898 	void (*check_preempt_curr) (struct rq *rq, struct task_struct *p);
899 
900 	struct task_struct * (*pick_next_task) (struct rq *rq);
901 	void (*put_prev_task) (struct rq *rq, struct task_struct *p);
902 
903 #ifdef CONFIG_SMP
904 	unsigned long (*load_balance) (struct rq *this_rq, int this_cpu,
905 			struct rq *busiest, unsigned long max_load_move,
906 			struct sched_domain *sd, enum cpu_idle_type idle,
907 			int *all_pinned, int *this_best_prio);
908 
909 	int (*move_one_task) (struct rq *this_rq, int this_cpu,
910 			      struct rq *busiest, struct sched_domain *sd,
911 			      enum cpu_idle_type idle);
912 	void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
913 	void (*post_schedule) (struct rq *this_rq);
914 	void (*task_wake_up) (struct rq *this_rq, struct task_struct *task);
915 #endif
916 
917 	void (*set_curr_task) (struct rq *rq);
918 	void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
919 	void (*task_new) (struct rq *rq, struct task_struct *p);
920 	void (*set_cpus_allowed)(struct task_struct *p,
921 				 const cpumask_t *newmask);
922 
923 	void (*join_domain)(struct rq *rq);
924 	void (*leave_domain)(struct rq *rq);
925 
926 	void (*switched_from) (struct rq *this_rq, struct task_struct *task,
927 			       int running);
928 	void (*switched_to) (struct rq *this_rq, struct task_struct *task,
929 			     int running);
930 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
931 			     int oldprio, int running);
932 
933 #ifdef CONFIG_FAIR_GROUP_SCHED
934 	void (*moved_group) (struct task_struct *p);
935 #endif
936 };
937 
938 struct load_weight {
939 	unsigned long weight, inv_weight;
940 };
941 
942 /*
943  * CFS stats for a schedulable entity (task, task-group etc)
944  *
945  * Current field usage histogram:
946  *
947  *     4 se->block_start
948  *     4 se->run_node
949  *     4 se->sleep_start
950  *     6 se->load.weight
951  */
952 struct sched_entity {
953 	struct load_weight	load;		/* for load-balancing */
954 	struct rb_node		run_node;
955 	struct list_head	group_node;
956 	unsigned int		on_rq;
957 
958 	u64			exec_start;
959 	u64			sum_exec_runtime;
960 	u64			vruntime;
961 	u64			prev_sum_exec_runtime;
962 
963 	u64			last_wakeup;
964 	u64			avg_overlap;
965 
966 #ifdef CONFIG_SCHEDSTATS
967 	u64			wait_start;
968 	u64			wait_max;
969 	u64			wait_count;
970 	u64			wait_sum;
971 
972 	u64			sleep_start;
973 	u64			sleep_max;
974 	s64			sum_sleep_runtime;
975 
976 	u64			block_start;
977 	u64			block_max;
978 	u64			exec_max;
979 	u64			slice_max;
980 
981 	u64			nr_migrations;
982 	u64			nr_migrations_cold;
983 	u64			nr_failed_migrations_affine;
984 	u64			nr_failed_migrations_running;
985 	u64			nr_failed_migrations_hot;
986 	u64			nr_forced_migrations;
987 	u64			nr_forced2_migrations;
988 
989 	u64			nr_wakeups;
990 	u64			nr_wakeups_sync;
991 	u64			nr_wakeups_migrate;
992 	u64			nr_wakeups_local;
993 	u64			nr_wakeups_remote;
994 	u64			nr_wakeups_affine;
995 	u64			nr_wakeups_affine_attempts;
996 	u64			nr_wakeups_passive;
997 	u64			nr_wakeups_idle;
998 #endif
999 
1000 #ifdef CONFIG_FAIR_GROUP_SCHED
1001 	struct sched_entity	*parent;
1002 	/* rq on which this entity is (to be) queued: */
1003 	struct cfs_rq		*cfs_rq;
1004 	/* rq "owned" by this entity/group: */
1005 	struct cfs_rq		*my_q;
1006 #endif
1007 };
1008 
1009 struct sched_rt_entity {
1010 	struct list_head run_list;
1011 	unsigned int time_slice;
1012 	unsigned long timeout;
1013 	int nr_cpus_allowed;
1014 
1015 	struct sched_rt_entity *back;
1016 #ifdef CONFIG_RT_GROUP_SCHED
1017 	struct sched_rt_entity	*parent;
1018 	/* rq on which this entity is (to be) queued: */
1019 	struct rt_rq		*rt_rq;
1020 	/* rq "owned" by this entity/group: */
1021 	struct rt_rq		*my_q;
1022 #endif
1023 };
1024 
1025 struct task_struct {
1026 	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
1027 	void *stack;
1028 	atomic_t usage;
1029 	unsigned int flags;	/* per process flags, defined below */
1030 	unsigned int ptrace;
1031 
1032 	int lock_depth;		/* BKL lock depth */
1033 
1034 #ifdef CONFIG_SMP
1035 #ifdef __ARCH_WANT_UNLOCKED_CTXSW
1036 	int oncpu;
1037 #endif
1038 #endif
1039 
1040 	int prio, static_prio, normal_prio;
1041 	const struct sched_class *sched_class;
1042 	struct sched_entity se;
1043 	struct sched_rt_entity rt;
1044 
1045 #ifdef CONFIG_PREEMPT_NOTIFIERS
1046 	/* list of struct preempt_notifier: */
1047 	struct hlist_head preempt_notifiers;
1048 #endif
1049 
1050 	/*
1051 	 * fpu_counter contains the number of consecutive context switches
1052 	 * that the FPU is used. If this is over a threshold, the lazy fpu
1053 	 * saving becomes unlazy to save the trap. This is an unsigned char
1054 	 * so that after 256 times the counter wraps and the behavior turns
1055 	 * lazy again; this to deal with bursty apps that only use FPU for
1056 	 * a short time
1057 	 */
1058 	unsigned char fpu_counter;
1059 	s8 oomkilladj; /* OOM kill score adjustment (bit shift). */
1060 #ifdef CONFIG_BLK_DEV_IO_TRACE
1061 	unsigned int btrace_seq;
1062 #endif
1063 
1064 	unsigned int policy;
1065 	cpumask_t cpus_allowed;
1066 
1067 #ifdef CONFIG_PREEMPT_RCU
1068 	int rcu_read_lock_nesting;
1069 	int rcu_flipctr_idx;
1070 #endif /* #ifdef CONFIG_PREEMPT_RCU */
1071 
1072 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1073 	struct sched_info sched_info;
1074 #endif
1075 
1076 	struct list_head tasks;
1077 	/*
1078 	 * ptrace_list/ptrace_children forms the list of my children
1079 	 * that were stolen by a ptracer.
1080 	 */
1081 	struct list_head ptrace_children;
1082 	struct list_head ptrace_list;
1083 
1084 	struct mm_struct *mm, *active_mm;
1085 
1086 /* task state */
1087 	struct linux_binfmt *binfmt;
1088 	int exit_state;
1089 	int exit_code, exit_signal;
1090 	int pdeath_signal;  /*  The signal sent when the parent dies  */
1091 	/* ??? */
1092 	unsigned int personality;
1093 	unsigned did_exec:1;
1094 	pid_t pid;
1095 	pid_t tgid;
1096 
1097 #ifdef CONFIG_CC_STACKPROTECTOR
1098 	/* Canary value for the -fstack-protector gcc feature */
1099 	unsigned long stack_canary;
1100 #endif
1101 	/*
1102 	 * pointers to (original) parent process, youngest child, younger sibling,
1103 	 * older sibling, respectively.  (p->father can be replaced with
1104 	 * p->parent->pid)
1105 	 */
1106 	struct task_struct *real_parent; /* real parent process (when being debugged) */
1107 	struct task_struct *parent;	/* parent process */
1108 	/*
1109 	 * children/sibling forms the list of my children plus the
1110 	 * tasks I'm ptracing.
1111 	 */
1112 	struct list_head children;	/* list of my children */
1113 	struct list_head sibling;	/* linkage in my parent's children list */
1114 	struct task_struct *group_leader;	/* threadgroup leader */
1115 
1116 	/* PID/PID hash table linkage. */
1117 	struct pid_link pids[PIDTYPE_MAX];
1118 	struct list_head thread_group;
1119 
1120 	struct completion *vfork_done;		/* for vfork() */
1121 	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
1122 	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
1123 
1124 	unsigned int rt_priority;
1125 	cputime_t utime, stime, utimescaled, stimescaled;
1126 	cputime_t gtime;
1127 	cputime_t prev_utime, prev_stime;
1128 	unsigned long nvcsw, nivcsw; /* context switch counts */
1129 	struct timespec start_time; 		/* monotonic time */
1130 	struct timespec real_start_time;	/* boot based time */
1131 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1132 	unsigned long min_flt, maj_flt;
1133 
1134   	cputime_t it_prof_expires, it_virt_expires;
1135 	unsigned long long it_sched_expires;
1136 	struct list_head cpu_timers[3];
1137 
1138 /* process credentials */
1139 	uid_t uid,euid,suid,fsuid;
1140 	gid_t gid,egid,sgid,fsgid;
1141 	struct group_info *group_info;
1142 	kernel_cap_t   cap_effective, cap_inheritable, cap_permitted, cap_bset;
1143 	unsigned securebits;
1144 	struct user_struct *user;
1145 #ifdef CONFIG_KEYS
1146 	struct key *request_key_auth;	/* assumed request_key authority */
1147 	struct key *thread_keyring;	/* keyring private to this thread */
1148 	unsigned char jit_keyring;	/* default keyring to attach requested keys to */
1149 #endif
1150 	char comm[TASK_COMM_LEN]; /* executable name excluding path
1151 				     - access with [gs]et_task_comm (which lock
1152 				       it with task_lock())
1153 				     - initialized normally by flush_old_exec */
1154 /* file system info */
1155 	int link_count, total_link_count;
1156 #ifdef CONFIG_SYSVIPC
1157 /* ipc stuff */
1158 	struct sysv_sem sysvsem;
1159 #endif
1160 #ifdef CONFIG_DETECT_SOFTLOCKUP
1161 /* hung task detection */
1162 	unsigned long last_switch_timestamp;
1163 	unsigned long last_switch_count;
1164 #endif
1165 /* CPU-specific state of this task */
1166 	struct thread_struct thread;
1167 /* filesystem information */
1168 	struct fs_struct *fs;
1169 /* open file information */
1170 	struct files_struct *files;
1171 /* namespaces */
1172 	struct nsproxy *nsproxy;
1173 /* signal handlers */
1174 	struct signal_struct *signal;
1175 	struct sighand_struct *sighand;
1176 
1177 	sigset_t blocked, real_blocked;
1178 	sigset_t saved_sigmask;	/* restored if set_restore_sigmask() was used */
1179 	struct sigpending pending;
1180 
1181 	unsigned long sas_ss_sp;
1182 	size_t sas_ss_size;
1183 	int (*notifier)(void *priv);
1184 	void *notifier_data;
1185 	sigset_t *notifier_mask;
1186 #ifdef CONFIG_SECURITY
1187 	void *security;
1188 #endif
1189 	struct audit_context *audit_context;
1190 #ifdef CONFIG_AUDITSYSCALL
1191 	uid_t loginuid;
1192 	unsigned int sessionid;
1193 #endif
1194 	seccomp_t seccomp;
1195 
1196 /* Thread group tracking */
1197    	u32 parent_exec_id;
1198    	u32 self_exec_id;
1199 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
1200 	spinlock_t alloc_lock;
1201 
1202 	/* Protection of the PI data structures: */
1203 	spinlock_t pi_lock;
1204 
1205 #ifdef CONFIG_RT_MUTEXES
1206 	/* PI waiters blocked on a rt_mutex held by this task */
1207 	struct plist_head pi_waiters;
1208 	/* Deadlock detection and priority inheritance handling */
1209 	struct rt_mutex_waiter *pi_blocked_on;
1210 #endif
1211 
1212 #ifdef CONFIG_DEBUG_MUTEXES
1213 	/* mutex deadlock detection */
1214 	struct mutex_waiter *blocked_on;
1215 #endif
1216 #ifdef CONFIG_TRACE_IRQFLAGS
1217 	unsigned int irq_events;
1218 	int hardirqs_enabled;
1219 	unsigned long hardirq_enable_ip;
1220 	unsigned int hardirq_enable_event;
1221 	unsigned long hardirq_disable_ip;
1222 	unsigned int hardirq_disable_event;
1223 	int softirqs_enabled;
1224 	unsigned long softirq_disable_ip;
1225 	unsigned int softirq_disable_event;
1226 	unsigned long softirq_enable_ip;
1227 	unsigned int softirq_enable_event;
1228 	int hardirq_context;
1229 	int softirq_context;
1230 #endif
1231 #ifdef CONFIG_LOCKDEP
1232 # define MAX_LOCK_DEPTH 48UL
1233 	u64 curr_chain_key;
1234 	int lockdep_depth;
1235 	struct held_lock held_locks[MAX_LOCK_DEPTH];
1236 	unsigned int lockdep_recursion;
1237 #endif
1238 
1239 /* journalling filesystem info */
1240 	void *journal_info;
1241 
1242 /* stacked block device info */
1243 	struct bio *bio_list, **bio_tail;
1244 
1245 /* VM state */
1246 	struct reclaim_state *reclaim_state;
1247 
1248 	struct backing_dev_info *backing_dev_info;
1249 
1250 	struct io_context *io_context;
1251 
1252 	unsigned long ptrace_message;
1253 	siginfo_t *last_siginfo; /* For ptrace use.  */
1254 #ifdef CONFIG_TASK_XACCT
1255 /* i/o counters(bytes read/written, #syscalls */
1256 	u64 rchar, wchar, syscr, syscw;
1257 #endif
1258 	struct task_io_accounting ioac;
1259 #if defined(CONFIG_TASK_XACCT)
1260 	u64 acct_rss_mem1;	/* accumulated rss usage */
1261 	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1262 	cputime_t acct_stimexpd;/* stime since last update */
1263 #endif
1264 #ifdef CONFIG_NUMA
1265   	struct mempolicy *mempolicy;
1266 	short il_next;
1267 #endif
1268 #ifdef CONFIG_CPUSETS
1269 	nodemask_t mems_allowed;
1270 	int cpuset_mems_generation;
1271 	int cpuset_mem_spread_rotor;
1272 #endif
1273 #ifdef CONFIG_CGROUPS
1274 	/* Control Group info protected by css_set_lock */
1275 	struct css_set *cgroups;
1276 	/* cg_list protected by css_set_lock and tsk->alloc_lock */
1277 	struct list_head cg_list;
1278 #endif
1279 #ifdef CONFIG_FUTEX
1280 	struct robust_list_head __user *robust_list;
1281 #ifdef CONFIG_COMPAT
1282 	struct compat_robust_list_head __user *compat_robust_list;
1283 #endif
1284 	struct list_head pi_state_list;
1285 	struct futex_pi_state *pi_state_cache;
1286 #endif
1287 	atomic_t fs_excl;	/* holding fs exclusive resources */
1288 	struct rcu_head rcu;
1289 
1290 	/*
1291 	 * cache last used pipe for splice
1292 	 */
1293 	struct pipe_inode_info *splice_pipe;
1294 #ifdef	CONFIG_TASK_DELAY_ACCT
1295 	struct task_delay_info *delays;
1296 #endif
1297 #ifdef CONFIG_FAULT_INJECTION
1298 	int make_it_fail;
1299 #endif
1300 	struct prop_local_single dirties;
1301 #ifdef CONFIG_LATENCYTOP
1302 	int latency_record_count;
1303 	struct latency_record latency_record[LT_SAVECOUNT];
1304 #endif
1305 };
1306 
1307 /*
1308  * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1309  * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1310  * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1311  * values are inverted: lower p->prio value means higher priority.
1312  *
1313  * The MAX_USER_RT_PRIO value allows the actual maximum
1314  * RT priority to be separate from the value exported to
1315  * user-space.  This allows kernel threads to set their
1316  * priority to a value higher than any user task. Note:
1317  * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1318  */
1319 
1320 #define MAX_USER_RT_PRIO	100
1321 #define MAX_RT_PRIO		MAX_USER_RT_PRIO
1322 
1323 #define MAX_PRIO		(MAX_RT_PRIO + 40)
1324 #define DEFAULT_PRIO		(MAX_RT_PRIO + 20)
1325 
1326 static inline int rt_prio(int prio)
1327 {
1328 	if (unlikely(prio < MAX_RT_PRIO))
1329 		return 1;
1330 	return 0;
1331 }
1332 
1333 static inline int rt_task(struct task_struct *p)
1334 {
1335 	return rt_prio(p->prio);
1336 }
1337 
1338 static inline void set_task_session(struct task_struct *tsk, pid_t session)
1339 {
1340 	tsk->signal->__session = session;
1341 }
1342 
1343 static inline void set_task_pgrp(struct task_struct *tsk, pid_t pgrp)
1344 {
1345 	tsk->signal->__pgrp = pgrp;
1346 }
1347 
1348 static inline struct pid *task_pid(struct task_struct *task)
1349 {
1350 	return task->pids[PIDTYPE_PID].pid;
1351 }
1352 
1353 static inline struct pid *task_tgid(struct task_struct *task)
1354 {
1355 	return task->group_leader->pids[PIDTYPE_PID].pid;
1356 }
1357 
1358 static inline struct pid *task_pgrp(struct task_struct *task)
1359 {
1360 	return task->group_leader->pids[PIDTYPE_PGID].pid;
1361 }
1362 
1363 static inline struct pid *task_session(struct task_struct *task)
1364 {
1365 	return task->group_leader->pids[PIDTYPE_SID].pid;
1366 }
1367 
1368 struct pid_namespace;
1369 
1370 /*
1371  * the helpers to get the task's different pids as they are seen
1372  * from various namespaces
1373  *
1374  * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1375  * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1376  *                     current.
1377  * task_xid_nr_ns()  : id seen from the ns specified;
1378  *
1379  * set_task_vxid()   : assigns a virtual id to a task;
1380  *
1381  * see also pid_nr() etc in include/linux/pid.h
1382  */
1383 
1384 static inline pid_t task_pid_nr(struct task_struct *tsk)
1385 {
1386 	return tsk->pid;
1387 }
1388 
1389 pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1390 
1391 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1392 {
1393 	return pid_vnr(task_pid(tsk));
1394 }
1395 
1396 
1397 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1398 {
1399 	return tsk->tgid;
1400 }
1401 
1402 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1403 
1404 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1405 {
1406 	return pid_vnr(task_tgid(tsk));
1407 }
1408 
1409 
1410 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1411 {
1412 	return tsk->signal->__pgrp;
1413 }
1414 
1415 pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1416 
1417 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1418 {
1419 	return pid_vnr(task_pgrp(tsk));
1420 }
1421 
1422 
1423 static inline pid_t task_session_nr(struct task_struct *tsk)
1424 {
1425 	return tsk->signal->__session;
1426 }
1427 
1428 pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1429 
1430 static inline pid_t task_session_vnr(struct task_struct *tsk)
1431 {
1432 	return pid_vnr(task_session(tsk));
1433 }
1434 
1435 
1436 /**
1437  * pid_alive - check that a task structure is not stale
1438  * @p: Task structure to be checked.
1439  *
1440  * Test if a process is not yet dead (at most zombie state)
1441  * If pid_alive fails, then pointers within the task structure
1442  * can be stale and must not be dereferenced.
1443  */
1444 static inline int pid_alive(struct task_struct *p)
1445 {
1446 	return p->pids[PIDTYPE_PID].pid != NULL;
1447 }
1448 
1449 /**
1450  * is_global_init - check if a task structure is init
1451  * @tsk: Task structure to be checked.
1452  *
1453  * Check if a task structure is the first user space task the kernel created.
1454  */
1455 static inline int is_global_init(struct task_struct *tsk)
1456 {
1457 	return tsk->pid == 1;
1458 }
1459 
1460 /*
1461  * is_container_init:
1462  * check whether in the task is init in its own pid namespace.
1463  */
1464 extern int is_container_init(struct task_struct *tsk);
1465 
1466 extern struct pid *cad_pid;
1467 
1468 extern void free_task(struct task_struct *tsk);
1469 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1470 
1471 extern void __put_task_struct(struct task_struct *t);
1472 
1473 static inline void put_task_struct(struct task_struct *t)
1474 {
1475 	if (atomic_dec_and_test(&t->usage))
1476 		__put_task_struct(t);
1477 }
1478 
1479 /*
1480  * Per process flags
1481  */
1482 #define PF_ALIGNWARN	0x00000001	/* Print alignment warning msgs */
1483 					/* Not implemented yet, only for 486*/
1484 #define PF_STARTING	0x00000002	/* being created */
1485 #define PF_EXITING	0x00000004	/* getting shut down */
1486 #define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
1487 #define PF_VCPU		0x00000010	/* I'm a virtual CPU */
1488 #define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
1489 #define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
1490 #define PF_DUMPCORE	0x00000200	/* dumped core */
1491 #define PF_SIGNALED	0x00000400	/* killed by a signal */
1492 #define PF_MEMALLOC	0x00000800	/* Allocating memory */
1493 #define PF_FLUSHER	0x00001000	/* responsible for disk writeback */
1494 #define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
1495 #define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
1496 #define PF_FROZEN	0x00010000	/* frozen for system suspend */
1497 #define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
1498 #define PF_KSWAPD	0x00040000	/* I am kswapd */
1499 #define PF_SWAPOFF	0x00080000	/* I am in swapoff */
1500 #define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
1501 #define PF_BORROWED_MM	0x00200000	/* I am a kthread doing use_mm */
1502 #define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
1503 #define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
1504 #define PF_SPREAD_PAGE	0x01000000	/* Spread page cache over cpuset */
1505 #define PF_SPREAD_SLAB	0x02000000	/* Spread some slab caches over cpuset */
1506 #define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
1507 #define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
1508 #define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezeable */
1509 
1510 /*
1511  * Only the _current_ task can read/write to tsk->flags, but other
1512  * tasks can access tsk->flags in readonly mode for example
1513  * with tsk_used_math (like during threaded core dumping).
1514  * There is however an exception to this rule during ptrace
1515  * or during fork: the ptracer task is allowed to write to the
1516  * child->flags of its traced child (same goes for fork, the parent
1517  * can write to the child->flags), because we're guaranteed the
1518  * child is not running and in turn not changing child->flags
1519  * at the same time the parent does it.
1520  */
1521 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1522 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1523 #define clear_used_math() clear_stopped_child_used_math(current)
1524 #define set_used_math() set_stopped_child_used_math(current)
1525 #define conditional_stopped_child_used_math(condition, child) \
1526 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1527 #define conditional_used_math(condition) \
1528 	conditional_stopped_child_used_math(condition, current)
1529 #define copy_to_stopped_child_used_math(child) \
1530 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1531 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1532 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1533 #define used_math() tsk_used_math(current)
1534 
1535 #ifdef CONFIG_SMP
1536 extern int set_cpus_allowed_ptr(struct task_struct *p,
1537 				const cpumask_t *new_mask);
1538 #else
1539 static inline int set_cpus_allowed_ptr(struct task_struct *p,
1540 				       const cpumask_t *new_mask)
1541 {
1542 	if (!cpu_isset(0, *new_mask))
1543 		return -EINVAL;
1544 	return 0;
1545 }
1546 #endif
1547 static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1548 {
1549 	return set_cpus_allowed_ptr(p, &new_mask);
1550 }
1551 
1552 extern unsigned long long sched_clock(void);
1553 
1554 /*
1555  * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
1556  * clock constructed from sched_clock():
1557  */
1558 extern unsigned long long cpu_clock(int cpu);
1559 
1560 extern unsigned long long
1561 task_sched_runtime(struct task_struct *task);
1562 
1563 /* sched_exec is called by processes performing an exec */
1564 #ifdef CONFIG_SMP
1565 extern void sched_exec(void);
1566 #else
1567 #define sched_exec()   {}
1568 #endif
1569 
1570 extern void sched_clock_idle_sleep_event(void);
1571 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1572 
1573 #ifdef CONFIG_HOTPLUG_CPU
1574 extern void idle_task_exit(void);
1575 #else
1576 static inline void idle_task_exit(void) {}
1577 #endif
1578 
1579 extern void sched_idle_next(void);
1580 
1581 #if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
1582 extern void wake_up_idle_cpu(int cpu);
1583 #else
1584 static inline void wake_up_idle_cpu(int cpu) { }
1585 #endif
1586 
1587 #ifdef CONFIG_SCHED_DEBUG
1588 extern unsigned int sysctl_sched_latency;
1589 extern unsigned int sysctl_sched_min_granularity;
1590 extern unsigned int sysctl_sched_wakeup_granularity;
1591 extern unsigned int sysctl_sched_child_runs_first;
1592 extern unsigned int sysctl_sched_features;
1593 extern unsigned int sysctl_sched_migration_cost;
1594 extern unsigned int sysctl_sched_nr_migrate;
1595 
1596 int sched_nr_latency_handler(struct ctl_table *table, int write,
1597 		struct file *file, void __user *buffer, size_t *length,
1598 		loff_t *ppos);
1599 #endif
1600 extern unsigned int sysctl_sched_rt_period;
1601 extern int sysctl_sched_rt_runtime;
1602 
1603 int sched_rt_handler(struct ctl_table *table, int write,
1604 		struct file *filp, void __user *buffer, size_t *lenp,
1605 		loff_t *ppos);
1606 
1607 extern unsigned int sysctl_sched_compat_yield;
1608 
1609 #ifdef CONFIG_RT_MUTEXES
1610 extern int rt_mutex_getprio(struct task_struct *p);
1611 extern void rt_mutex_setprio(struct task_struct *p, int prio);
1612 extern void rt_mutex_adjust_pi(struct task_struct *p);
1613 #else
1614 static inline int rt_mutex_getprio(struct task_struct *p)
1615 {
1616 	return p->normal_prio;
1617 }
1618 # define rt_mutex_adjust_pi(p)		do { } while (0)
1619 #endif
1620 
1621 extern void set_user_nice(struct task_struct *p, long nice);
1622 extern int task_prio(const struct task_struct *p);
1623 extern int task_nice(const struct task_struct *p);
1624 extern int can_nice(const struct task_struct *p, const int nice);
1625 extern int task_curr(const struct task_struct *p);
1626 extern int idle_cpu(int cpu);
1627 extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1628 extern struct task_struct *idle_task(int cpu);
1629 extern struct task_struct *curr_task(int cpu);
1630 extern void set_curr_task(int cpu, struct task_struct *p);
1631 
1632 void yield(void);
1633 
1634 /*
1635  * The default (Linux) execution domain.
1636  */
1637 extern struct exec_domain	default_exec_domain;
1638 
1639 union thread_union {
1640 	struct thread_info thread_info;
1641 	unsigned long stack[THREAD_SIZE/sizeof(long)];
1642 };
1643 
1644 #ifndef __HAVE_ARCH_KSTACK_END
1645 static inline int kstack_end(void *addr)
1646 {
1647 	/* Reliable end of stack detection:
1648 	 * Some APM bios versions misalign the stack
1649 	 */
1650 	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1651 }
1652 #endif
1653 
1654 extern union thread_union init_thread_union;
1655 extern struct task_struct init_task;
1656 
1657 extern struct   mm_struct init_mm;
1658 
1659 extern struct pid_namespace init_pid_ns;
1660 
1661 /*
1662  * find a task by one of its numerical ids
1663  *
1664  * find_task_by_pid_type_ns():
1665  *      it is the most generic call - it finds a task by all id,
1666  *      type and namespace specified
1667  * find_task_by_pid_ns():
1668  *      finds a task by its pid in the specified namespace
1669  * find_task_by_vpid():
1670  *      finds a task by its virtual pid
1671  * find_task_by_pid():
1672  *      finds a task by its global pid
1673  *
1674  * see also find_pid() etc in include/linux/pid.h
1675  */
1676 
1677 extern struct task_struct *find_task_by_pid_type_ns(int type, int pid,
1678 		struct pid_namespace *ns);
1679 
1680 static inline struct task_struct *__deprecated find_task_by_pid(pid_t nr)
1681 {
1682 	return find_task_by_pid_type_ns(PIDTYPE_PID, nr, &init_pid_ns);
1683 }
1684 extern struct task_struct *find_task_by_vpid(pid_t nr);
1685 extern struct task_struct *find_task_by_pid_ns(pid_t nr,
1686 		struct pid_namespace *ns);
1687 
1688 extern void __set_special_pids(struct pid *pid);
1689 
1690 /* per-UID process charging. */
1691 extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
1692 static inline struct user_struct *get_uid(struct user_struct *u)
1693 {
1694 	atomic_inc(&u->__count);
1695 	return u;
1696 }
1697 extern void free_uid(struct user_struct *);
1698 extern void switch_uid(struct user_struct *);
1699 extern void release_uids(struct user_namespace *ns);
1700 
1701 #include <asm/current.h>
1702 
1703 extern void do_timer(unsigned long ticks);
1704 
1705 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1706 extern int wake_up_process(struct task_struct *tsk);
1707 extern void wake_up_new_task(struct task_struct *tsk,
1708 				unsigned long clone_flags);
1709 #ifdef CONFIG_SMP
1710  extern void kick_process(struct task_struct *tsk);
1711 #else
1712  static inline void kick_process(struct task_struct *tsk) { }
1713 #endif
1714 extern void sched_fork(struct task_struct *p, int clone_flags);
1715 extern void sched_dead(struct task_struct *p);
1716 
1717 extern int in_group_p(gid_t);
1718 extern int in_egroup_p(gid_t);
1719 
1720 extern void proc_caches_init(void);
1721 extern void flush_signals(struct task_struct *);
1722 extern void ignore_signals(struct task_struct *);
1723 extern void flush_signal_handlers(struct task_struct *, int force_default);
1724 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1725 
1726 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1727 {
1728 	unsigned long flags;
1729 	int ret;
1730 
1731 	spin_lock_irqsave(&tsk->sighand->siglock, flags);
1732 	ret = dequeue_signal(tsk, mask, info);
1733 	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1734 
1735 	return ret;
1736 }
1737 
1738 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1739 			      sigset_t *mask);
1740 extern void unblock_all_signals(void);
1741 extern void release_task(struct task_struct * p);
1742 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1743 extern int force_sigsegv(int, struct task_struct *);
1744 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1745 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1746 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
1747 extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
1748 extern int kill_pgrp(struct pid *pid, int sig, int priv);
1749 extern int kill_pid(struct pid *pid, int sig, int priv);
1750 extern int kill_proc_info(int, struct siginfo *, pid_t);
1751 extern void do_notify_parent(struct task_struct *, int);
1752 extern void force_sig(int, struct task_struct *);
1753 extern void force_sig_specific(int, struct task_struct *);
1754 extern int send_sig(int, struct task_struct *, int);
1755 extern void zap_other_threads(struct task_struct *p);
1756 extern int kill_proc(pid_t, int, int);
1757 extern struct sigqueue *sigqueue_alloc(void);
1758 extern void sigqueue_free(struct sigqueue *);
1759 extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
1760 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
1761 extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1762 
1763 static inline int kill_cad_pid(int sig, int priv)
1764 {
1765 	return kill_pid(cad_pid, sig, priv);
1766 }
1767 
1768 /* These can be the second arg to send_sig_info/send_group_sig_info.  */
1769 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
1770 #define SEND_SIG_PRIV	((struct siginfo *) 1)
1771 #define SEND_SIG_FORCED	((struct siginfo *) 2)
1772 
1773 static inline int is_si_special(const struct siginfo *info)
1774 {
1775 	return info <= SEND_SIG_FORCED;
1776 }
1777 
1778 /* True if we are on the alternate signal stack.  */
1779 
1780 static inline int on_sig_stack(unsigned long sp)
1781 {
1782 	return (sp - current->sas_ss_sp < current->sas_ss_size);
1783 }
1784 
1785 static inline int sas_ss_flags(unsigned long sp)
1786 {
1787 	return (current->sas_ss_size == 0 ? SS_DISABLE
1788 		: on_sig_stack(sp) ? SS_ONSTACK : 0);
1789 }
1790 
1791 /*
1792  * Routines for handling mm_structs
1793  */
1794 extern struct mm_struct * mm_alloc(void);
1795 
1796 /* mmdrop drops the mm and the page tables */
1797 extern void __mmdrop(struct mm_struct *);
1798 static inline void mmdrop(struct mm_struct * mm)
1799 {
1800 	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
1801 		__mmdrop(mm);
1802 }
1803 
1804 /* mmput gets rid of the mappings and all user-space */
1805 extern void mmput(struct mm_struct *);
1806 /* Grab a reference to a task's mm, if it is not already going away */
1807 extern struct mm_struct *get_task_mm(struct task_struct *task);
1808 /* Remove the current tasks stale references to the old mm_struct */
1809 extern void mm_release(struct task_struct *, struct mm_struct *);
1810 /* Allocate a new mm structure and copy contents from tsk->mm */
1811 extern struct mm_struct *dup_mm(struct task_struct *tsk);
1812 
1813 extern int  copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1814 extern void flush_thread(void);
1815 extern void exit_thread(void);
1816 
1817 extern void exit_files(struct task_struct *);
1818 extern void __cleanup_signal(struct signal_struct *);
1819 extern void __cleanup_sighand(struct sighand_struct *);
1820 extern void exit_itimers(struct signal_struct *);
1821 
1822 extern NORET_TYPE void do_group_exit(int);
1823 
1824 extern void daemonize(const char *, ...);
1825 extern int allow_signal(int);
1826 extern int disallow_signal(int);
1827 
1828 extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1829 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1830 struct task_struct *fork_idle(int);
1831 
1832 extern void set_task_comm(struct task_struct *tsk, char *from);
1833 extern char *get_task_comm(char *to, struct task_struct *tsk);
1834 
1835 #ifdef CONFIG_SMP
1836 extern void wait_task_inactive(struct task_struct * p);
1837 #else
1838 #define wait_task_inactive(p)	do { } while (0)
1839 #endif
1840 
1841 #define remove_parent(p)	list_del_init(&(p)->sibling)
1842 #define add_parent(p)		list_add_tail(&(p)->sibling,&(p)->parent->children)
1843 
1844 #define next_task(p)	list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
1845 
1846 #define for_each_process(p) \
1847 	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1848 
1849 /*
1850  * Careful: do_each_thread/while_each_thread is a double loop so
1851  *          'break' will not work as expected - use goto instead.
1852  */
1853 #define do_each_thread(g, t) \
1854 	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1855 
1856 #define while_each_thread(g, t) \
1857 	while ((t = next_thread(t)) != g)
1858 
1859 /* de_thread depends on thread_group_leader not being a pid based check */
1860 #define thread_group_leader(p)	(p == p->group_leader)
1861 
1862 /* Do to the insanities of de_thread it is possible for a process
1863  * to have the pid of the thread group leader without actually being
1864  * the thread group leader.  For iteration through the pids in proc
1865  * all we care about is that we have a task with the appropriate
1866  * pid, we don't actually care if we have the right task.
1867  */
1868 static inline int has_group_leader_pid(struct task_struct *p)
1869 {
1870 	return p->pid == p->tgid;
1871 }
1872 
1873 static inline
1874 int same_thread_group(struct task_struct *p1, struct task_struct *p2)
1875 {
1876 	return p1->tgid == p2->tgid;
1877 }
1878 
1879 static inline struct task_struct *next_thread(const struct task_struct *p)
1880 {
1881 	return list_entry(rcu_dereference(p->thread_group.next),
1882 			  struct task_struct, thread_group);
1883 }
1884 
1885 static inline int thread_group_empty(struct task_struct *p)
1886 {
1887 	return list_empty(&p->thread_group);
1888 }
1889 
1890 #define delay_group_leader(p) \
1891 		(thread_group_leader(p) && !thread_group_empty(p))
1892 
1893 /*
1894  * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
1895  * subscriptions and synchronises with wait4().  Also used in procfs.  Also
1896  * pins the final release of task.io_context.  Also protects ->cpuset and
1897  * ->cgroup.subsys[].
1898  *
1899  * Nests both inside and outside of read_lock(&tasklist_lock).
1900  * It must not be nested with write_lock_irq(&tasklist_lock),
1901  * neither inside nor outside.
1902  */
1903 static inline void task_lock(struct task_struct *p)
1904 {
1905 	spin_lock(&p->alloc_lock);
1906 }
1907 
1908 static inline void task_unlock(struct task_struct *p)
1909 {
1910 	spin_unlock(&p->alloc_lock);
1911 }
1912 
1913 extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
1914 							unsigned long *flags);
1915 
1916 static inline void unlock_task_sighand(struct task_struct *tsk,
1917 						unsigned long *flags)
1918 {
1919 	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
1920 }
1921 
1922 #ifndef __HAVE_THREAD_FUNCTIONS
1923 
1924 #define task_thread_info(task)	((struct thread_info *)(task)->stack)
1925 #define task_stack_page(task)	((task)->stack)
1926 
1927 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
1928 {
1929 	*task_thread_info(p) = *task_thread_info(org);
1930 	task_thread_info(p)->task = p;
1931 }
1932 
1933 static inline unsigned long *end_of_stack(struct task_struct *p)
1934 {
1935 	return (unsigned long *)(task_thread_info(p) + 1);
1936 }
1937 
1938 #endif
1939 
1940 extern void thread_info_cache_init(void);
1941 
1942 /* set thread flags in other task's structures
1943  * - see asm/thread_info.h for TIF_xxxx flags available
1944  */
1945 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1946 {
1947 	set_ti_thread_flag(task_thread_info(tsk), flag);
1948 }
1949 
1950 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1951 {
1952 	clear_ti_thread_flag(task_thread_info(tsk), flag);
1953 }
1954 
1955 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1956 {
1957 	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1958 }
1959 
1960 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1961 {
1962 	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1963 }
1964 
1965 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1966 {
1967 	return test_ti_thread_flag(task_thread_info(tsk), flag);
1968 }
1969 
1970 static inline void set_tsk_need_resched(struct task_struct *tsk)
1971 {
1972 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1973 }
1974 
1975 static inline void clear_tsk_need_resched(struct task_struct *tsk)
1976 {
1977 	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1978 }
1979 
1980 static inline int signal_pending(struct task_struct *p)
1981 {
1982 	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1983 }
1984 
1985 extern int __fatal_signal_pending(struct task_struct *p);
1986 
1987 static inline int fatal_signal_pending(struct task_struct *p)
1988 {
1989 	return signal_pending(p) && __fatal_signal_pending(p);
1990 }
1991 
1992 static inline int need_resched(void)
1993 {
1994 	return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1995 }
1996 
1997 /*
1998  * cond_resched() and cond_resched_lock(): latency reduction via
1999  * explicit rescheduling in places that are safe. The return
2000  * value indicates whether a reschedule was done in fact.
2001  * cond_resched_lock() will drop the spinlock before scheduling,
2002  * cond_resched_softirq() will enable bhs before scheduling.
2003  */
2004 #ifdef CONFIG_PREEMPT
2005 static inline int cond_resched(void)
2006 {
2007 	return 0;
2008 }
2009 #else
2010 extern int _cond_resched(void);
2011 static inline int cond_resched(void)
2012 {
2013 	return _cond_resched();
2014 }
2015 #endif
2016 extern int cond_resched_lock(spinlock_t * lock);
2017 extern int cond_resched_softirq(void);
2018 
2019 /*
2020  * Does a critical section need to be broken due to another
2021  * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2022  * but a general need for low latency)
2023  */
2024 static inline int spin_needbreak(spinlock_t *lock)
2025 {
2026 #ifdef CONFIG_PREEMPT
2027 	return spin_is_contended(lock);
2028 #else
2029 	return 0;
2030 #endif
2031 }
2032 
2033 /*
2034  * Reevaluate whether the task has signals pending delivery.
2035  * Wake the task if so.
2036  * This is required every time the blocked sigset_t changes.
2037  * callers must hold sighand->siglock.
2038  */
2039 extern void recalc_sigpending_and_wake(struct task_struct *t);
2040 extern void recalc_sigpending(void);
2041 
2042 extern void signal_wake_up(struct task_struct *t, int resume_stopped);
2043 
2044 /*
2045  * Wrappers for p->thread_info->cpu access. No-op on UP.
2046  */
2047 #ifdef CONFIG_SMP
2048 
2049 static inline unsigned int task_cpu(const struct task_struct *p)
2050 {
2051 	return task_thread_info(p)->cpu;
2052 }
2053 
2054 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2055 
2056 #else
2057 
2058 static inline unsigned int task_cpu(const struct task_struct *p)
2059 {
2060 	return 0;
2061 }
2062 
2063 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2064 {
2065 }
2066 
2067 #endif /* CONFIG_SMP */
2068 
2069 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
2070 extern void arch_pick_mmap_layout(struct mm_struct *mm);
2071 #else
2072 static inline void arch_pick_mmap_layout(struct mm_struct *mm)
2073 {
2074 	mm->mmap_base = TASK_UNMAPPED_BASE;
2075 	mm->get_unmapped_area = arch_get_unmapped_area;
2076 	mm->unmap_area = arch_unmap_area;
2077 }
2078 #endif
2079 
2080 extern long sched_setaffinity(pid_t pid, const cpumask_t *new_mask);
2081 extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
2082 
2083 extern int sched_mc_power_savings, sched_smt_power_savings;
2084 
2085 extern void normalize_rt_tasks(void);
2086 
2087 #ifdef CONFIG_GROUP_SCHED
2088 
2089 extern struct task_group init_task_group;
2090 #ifdef CONFIG_USER_SCHED
2091 extern struct task_group root_task_group;
2092 #endif
2093 
2094 extern struct task_group *sched_create_group(struct task_group *parent);
2095 extern void sched_destroy_group(struct task_group *tg);
2096 extern void sched_move_task(struct task_struct *tsk);
2097 #ifdef CONFIG_FAIR_GROUP_SCHED
2098 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2099 extern unsigned long sched_group_shares(struct task_group *tg);
2100 #endif
2101 #ifdef CONFIG_RT_GROUP_SCHED
2102 extern int sched_group_set_rt_runtime(struct task_group *tg,
2103 				      long rt_runtime_us);
2104 extern long sched_group_rt_runtime(struct task_group *tg);
2105 extern int sched_group_set_rt_period(struct task_group *tg,
2106 				      long rt_period_us);
2107 extern long sched_group_rt_period(struct task_group *tg);
2108 #endif
2109 #endif
2110 
2111 #ifdef CONFIG_TASK_XACCT
2112 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2113 {
2114 	tsk->rchar += amt;
2115 }
2116 
2117 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2118 {
2119 	tsk->wchar += amt;
2120 }
2121 
2122 static inline void inc_syscr(struct task_struct *tsk)
2123 {
2124 	tsk->syscr++;
2125 }
2126 
2127 static inline void inc_syscw(struct task_struct *tsk)
2128 {
2129 	tsk->syscw++;
2130 }
2131 #else
2132 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2133 {
2134 }
2135 
2136 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2137 {
2138 }
2139 
2140 static inline void inc_syscr(struct task_struct *tsk)
2141 {
2142 }
2143 
2144 static inline void inc_syscw(struct task_struct *tsk)
2145 {
2146 }
2147 #endif
2148 
2149 #ifdef CONFIG_SMP
2150 void migration_init(void);
2151 #else
2152 static inline void migration_init(void)
2153 {
2154 }
2155 #endif
2156 
2157 #ifndef TASK_SIZE_OF
2158 #define TASK_SIZE_OF(tsk)	TASK_SIZE
2159 #endif
2160 
2161 #ifdef CONFIG_MM_OWNER
2162 extern void mm_update_next_owner(struct mm_struct *mm);
2163 extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2164 #else
2165 static inline void mm_update_next_owner(struct mm_struct *mm)
2166 {
2167 }
2168 
2169 static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2170 {
2171 }
2172 #endif /* CONFIG_MM_OWNER */
2173 
2174 #endif /* __KERNEL__ */
2175 
2176 #endif
2177