sched.h revision 7d8e23df69820e6be42bcc41d441f4860e8c76f7
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
44struct 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#include <linux/cred.h>
91
92#include <asm/processor.h>
93
94struct mem_cgroup;
95struct exec_domain;
96struct futex_pi_state;
97struct robust_list_head;
98struct bio;
99struct bts_tracer;
100
101/*
102 * List of flags we want to share for kernel threads,
103 * if only because they are not used by them anyway.
104 */
105#define CLONE_KERNEL	(CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
106
107/*
108 * These are the constant used to fake the fixed-point load-average
109 * counting. Some notes:
110 *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
111 *    a load-average precision of 10 bits integer + 11 bits fractional
112 *  - if you want to count load-averages more often, you need more
113 *    precision, or rounding will get you. With 2-second counting freq,
114 *    the EXP_n values would be 1981, 2034 and 2043 if still using only
115 *    11 bit fractions.
116 */
117extern unsigned long avenrun[];		/* Load averages */
118
119#define FSHIFT		11		/* nr of bits of precision */
120#define FIXED_1		(1<<FSHIFT)	/* 1.0 as fixed-point */
121#define LOAD_FREQ	(5*HZ+1)	/* 5 sec intervals */
122#define EXP_1		1884		/* 1/exp(5sec/1min) as fixed-point */
123#define EXP_5		2014		/* 1/exp(5sec/5min) */
124#define EXP_15		2037		/* 1/exp(5sec/15min) */
125
126#define CALC_LOAD(load,exp,n) \
127	load *= exp; \
128	load += n*(FIXED_1-exp); \
129	load >>= FSHIFT;
130
131extern unsigned long total_forks;
132extern int nr_threads;
133DECLARE_PER_CPU(unsigned long, process_counts);
134extern int nr_processes(void);
135extern unsigned long nr_running(void);
136extern unsigned long nr_uninterruptible(void);
137extern unsigned long nr_active(void);
138extern unsigned long nr_iowait(void);
139
140struct seq_file;
141struct cfs_rq;
142struct task_group;
143#ifdef CONFIG_SCHED_DEBUG
144extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
145extern void proc_sched_set_task(struct task_struct *p);
146extern void
147print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
148#else
149static inline void
150proc_sched_show_task(struct task_struct *p, struct seq_file *m)
151{
152}
153static inline void proc_sched_set_task(struct task_struct *p)
154{
155}
156static inline void
157print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
158{
159}
160#endif
161
162extern unsigned long long time_sync_thresh;
163
164/*
165 * Task state bitmask. NOTE! These bits are also
166 * encoded in fs/proc/array.c: get_task_state().
167 *
168 * We have two separate sets of flags: task->state
169 * is about runnability, while task->exit_state are
170 * about the task exiting. Confusing, but this way
171 * modifying one set can't modify the other one by
172 * mistake.
173 */
174#define TASK_RUNNING		0
175#define TASK_INTERRUPTIBLE	1
176#define TASK_UNINTERRUPTIBLE	2
177#define __TASK_STOPPED		4
178#define __TASK_TRACED		8
179/* in tsk->exit_state */
180#define EXIT_ZOMBIE		16
181#define EXIT_DEAD		32
182/* in tsk->state again */
183#define TASK_DEAD		64
184#define TASK_WAKEKILL		128
185
186/* Convenience macros for the sake of set_task_state */
187#define TASK_KILLABLE		(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
188#define TASK_STOPPED		(TASK_WAKEKILL | __TASK_STOPPED)
189#define TASK_TRACED		(TASK_WAKEKILL | __TASK_TRACED)
190
191/* Convenience macros for the sake of wake_up */
192#define TASK_NORMAL		(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
193#define TASK_ALL		(TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
194
195/* get_task_state() */
196#define TASK_REPORT		(TASK_RUNNING | TASK_INTERRUPTIBLE | \
197				 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
198				 __TASK_TRACED)
199
200#define task_is_traced(task)	((task->state & __TASK_TRACED) != 0)
201#define task_is_stopped(task)	((task->state & __TASK_STOPPED) != 0)
202#define task_is_stopped_or_traced(task)	\
203			((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
204#define task_contributes_to_load(task)	\
205				((task->state & TASK_UNINTERRUPTIBLE) != 0)
206
207#define __set_task_state(tsk, state_value)		\
208	do { (tsk)->state = (state_value); } while (0)
209#define set_task_state(tsk, state_value)		\
210	set_mb((tsk)->state, (state_value))
211
212/*
213 * set_current_state() includes a barrier so that the write of current->state
214 * is correctly serialised wrt the caller's subsequent test of whether to
215 * actually sleep:
216 *
217 *	set_current_state(TASK_UNINTERRUPTIBLE);
218 *	if (do_i_need_to_sleep())
219 *		schedule();
220 *
221 * If the caller does not need such serialisation then use __set_current_state()
222 */
223#define __set_current_state(state_value)			\
224	do { current->state = (state_value); } while (0)
225#define set_current_state(state_value)		\
226	set_mb(current->state, (state_value))
227
228/* Task command name length */
229#define TASK_COMM_LEN 16
230
231#include <linux/spinlock.h>
232
233/*
234 * This serializes "schedule()" and also protects
235 * the run-queue from deletions/modifications (but
236 * _adding_ to the beginning of the run-queue has
237 * a separate lock).
238 */
239extern rwlock_t tasklist_lock;
240extern spinlock_t mmlist_lock;
241
242struct task_struct;
243
244extern void sched_init(void);
245extern void sched_init_smp(void);
246extern asmlinkage void schedule_tail(struct task_struct *prev);
247extern void init_idle(struct task_struct *idle, int cpu);
248extern void init_idle_bootup_task(struct task_struct *idle);
249
250extern int runqueue_is_locked(void);
251extern void task_rq_unlock_wait(struct task_struct *p);
252
253extern cpumask_var_t nohz_cpu_mask;
254#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
255extern int select_nohz_load_balancer(int cpu);
256#else
257static inline int select_nohz_load_balancer(int cpu)
258{
259	return 0;
260}
261#endif
262
263/*
264 * Only dump TASK_* tasks. (0 for all tasks)
265 */
266extern void show_state_filter(unsigned long state_filter);
267
268static inline void show_state(void)
269{
270	show_state_filter(0);
271}
272
273extern void show_regs(struct pt_regs *);
274
275/*
276 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
277 * task), SP is the stack pointer of the first frame that should be shown in the back
278 * trace (or NULL if the entire call-chain of the task should be shown).
279 */
280extern void show_stack(struct task_struct *task, unsigned long *sp);
281
282void io_schedule(void);
283long io_schedule_timeout(long timeout);
284
285extern void cpu_init (void);
286extern void trap_init(void);
287extern void update_process_times(int user);
288extern void scheduler_tick(void);
289
290extern void sched_show_task(struct task_struct *p);
291
292#ifdef CONFIG_DETECT_SOFTLOCKUP
293extern void softlockup_tick(void);
294extern void touch_softlockup_watchdog(void);
295extern void touch_all_softlockup_watchdogs(void);
296extern int proc_dosoftlockup_thresh(struct ctl_table *table, int write,
297				    struct file *filp, void __user *buffer,
298				    size_t *lenp, loff_t *ppos);
299extern unsigned int  softlockup_panic;
300extern unsigned long sysctl_hung_task_check_count;
301extern unsigned long sysctl_hung_task_timeout_secs;
302extern unsigned long sysctl_hung_task_warnings;
303extern int softlockup_thresh;
304#else
305static inline void softlockup_tick(void)
306{
307}
308static inline void spawn_softlockup_task(void)
309{
310}
311static inline void touch_softlockup_watchdog(void)
312{
313}
314static inline void touch_all_softlockup_watchdogs(void)
315{
316}
317#endif
318
319
320/* Attach to any functions which should be ignored in wchan output. */
321#define __sched		__attribute__((__section__(".sched.text")))
322
323/* Linker adds these: start and end of __sched functions */
324extern char __sched_text_start[], __sched_text_end[];
325
326/* Is this address in the __sched functions? */
327extern int in_sched_functions(unsigned long addr);
328
329#define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
330extern signed long schedule_timeout(signed long timeout);
331extern signed long schedule_timeout_interruptible(signed long timeout);
332extern signed long schedule_timeout_killable(signed long timeout);
333extern signed long schedule_timeout_uninterruptible(signed long timeout);
334asmlinkage void schedule(void);
335
336struct nsproxy;
337struct user_namespace;
338
339/* Maximum number of active map areas.. This is a random (large) number */
340#define DEFAULT_MAX_MAP_COUNT	65536
341
342extern int sysctl_max_map_count;
343
344#include <linux/aio.h>
345
346extern unsigned long
347arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
348		       unsigned long, unsigned long);
349extern unsigned long
350arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
351			  unsigned long len, unsigned long pgoff,
352			  unsigned long flags);
353extern void arch_unmap_area(struct mm_struct *, unsigned long);
354extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
355
356#if USE_SPLIT_PTLOCKS
357/*
358 * The mm counters are not protected by its page_table_lock,
359 * so must be incremented atomically.
360 */
361#define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
362#define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
363#define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
364#define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
365#define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
366
367#else  /* !USE_SPLIT_PTLOCKS */
368/*
369 * The mm counters are protected by its page_table_lock,
370 * so can be incremented directly.
371 */
372#define set_mm_counter(mm, member, value) (mm)->_##member = (value)
373#define get_mm_counter(mm, member) ((mm)->_##member)
374#define add_mm_counter(mm, member, value) (mm)->_##member += (value)
375#define inc_mm_counter(mm, member) (mm)->_##member++
376#define dec_mm_counter(mm, member) (mm)->_##member--
377
378#endif /* !USE_SPLIT_PTLOCKS */
379
380#define get_mm_rss(mm)					\
381	(get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
382#define update_hiwater_rss(mm)	do {			\
383	unsigned long _rss = get_mm_rss(mm);		\
384	if ((mm)->hiwater_rss < _rss)			\
385		(mm)->hiwater_rss = _rss;		\
386} while (0)
387#define update_hiwater_vm(mm)	do {			\
388	if ((mm)->hiwater_vm < (mm)->total_vm)		\
389		(mm)->hiwater_vm = (mm)->total_vm;	\
390} while (0)
391
392#define get_mm_hiwater_rss(mm)	max((mm)->hiwater_rss, get_mm_rss(mm))
393#define get_mm_hiwater_vm(mm)	max((mm)->hiwater_vm, (mm)->total_vm)
394
395extern void set_dumpable(struct mm_struct *mm, int value);
396extern int get_dumpable(struct mm_struct *mm);
397
398/* mm flags */
399/* dumpable bits */
400#define MMF_DUMPABLE      0  /* core dump is permitted */
401#define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
402#define MMF_DUMPABLE_BITS 2
403
404/* coredump filter bits */
405#define MMF_DUMP_ANON_PRIVATE	2
406#define MMF_DUMP_ANON_SHARED	3
407#define MMF_DUMP_MAPPED_PRIVATE	4
408#define MMF_DUMP_MAPPED_SHARED	5
409#define MMF_DUMP_ELF_HEADERS	6
410#define MMF_DUMP_HUGETLB_PRIVATE 7
411#define MMF_DUMP_HUGETLB_SHARED  8
412#define MMF_DUMP_FILTER_SHIFT	MMF_DUMPABLE_BITS
413#define MMF_DUMP_FILTER_BITS	7
414#define MMF_DUMP_FILTER_MASK \
415	(((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
416#define MMF_DUMP_FILTER_DEFAULT \
417	((1 << MMF_DUMP_ANON_PRIVATE) |	(1 << MMF_DUMP_ANON_SHARED) |\
418	 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
419
420#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
421# define MMF_DUMP_MASK_DEFAULT_ELF	(1 << MMF_DUMP_ELF_HEADERS)
422#else
423# define MMF_DUMP_MASK_DEFAULT_ELF	0
424#endif
425
426struct sighand_struct {
427	atomic_t		count;
428	struct k_sigaction	action[_NSIG];
429	spinlock_t		siglock;
430	wait_queue_head_t	signalfd_wqh;
431};
432
433struct pacct_struct {
434	int			ac_flag;
435	long			ac_exitcode;
436	unsigned long		ac_mem;
437	cputime_t		ac_utime, ac_stime;
438	unsigned long		ac_minflt, ac_majflt;
439};
440
441/**
442 * struct task_cputime - collected CPU time counts
443 * @utime:		time spent in user mode, in &cputime_t units
444 * @stime:		time spent in kernel mode, in &cputime_t units
445 * @sum_exec_runtime:	total time spent on the CPU, in nanoseconds
446 *
447 * This structure groups together three kinds of CPU time that are
448 * tracked for threads and thread groups.  Most things considering
449 * CPU time want to group these counts together and treat all three
450 * of them in parallel.
451 */
452struct task_cputime {
453	cputime_t utime;
454	cputime_t stime;
455	unsigned long long sum_exec_runtime;
456};
457/* Alternate field names when used to cache expirations. */
458#define prof_exp	stime
459#define virt_exp	utime
460#define sched_exp	sum_exec_runtime
461
462#define INIT_CPUTIME	\
463	(struct task_cputime) {					\
464		.utime = cputime_zero,				\
465		.stime = cputime_zero,				\
466		.sum_exec_runtime = 0,				\
467	}
468
469/**
470 * struct thread_group_cputimer - thread group interval timer counts
471 * @cputime:		thread group interval timers.
472 * @running:		non-zero when there are timers running and
473 * 			@cputime receives updates.
474 * @lock:		lock for fields in this struct.
475 *
476 * This structure contains the version of task_cputime, above, that is
477 * used for thread group CPU timer calculations.
478 */
479struct thread_group_cputimer {
480	struct task_cputime cputime;
481	int running;
482	spinlock_t lock;
483};
484
485/*
486 * NOTE! "signal_struct" does not have it's own
487 * locking, because a shared signal_struct always
488 * implies a shared sighand_struct, so locking
489 * sighand_struct is always a proper superset of
490 * the locking of signal_struct.
491 */
492struct signal_struct {
493	atomic_t		count;
494	atomic_t		live;
495
496	wait_queue_head_t	wait_chldexit;	/* for wait4() */
497
498	/* current thread group signal load-balancing target: */
499	struct task_struct	*curr_target;
500
501	/* shared signal handling: */
502	struct sigpending	shared_pending;
503
504	/* thread group exit support */
505	int			group_exit_code;
506	/* overloaded:
507	 * - notify group_exit_task when ->count is equal to notify_count
508	 * - everyone except group_exit_task is stopped during signal delivery
509	 *   of fatal signals, group_exit_task processes the signal.
510	 */
511	int			notify_count;
512	struct task_struct	*group_exit_task;
513
514	/* thread group stop support, overloads group_exit_code too */
515	int			group_stop_count;
516	unsigned int		flags; /* see SIGNAL_* flags below */
517
518	/* POSIX.1b Interval Timers */
519	struct list_head posix_timers;
520
521	/* ITIMER_REAL timer for the process */
522	struct hrtimer real_timer;
523	struct pid *leader_pid;
524	ktime_t it_real_incr;
525
526	/* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
527	cputime_t it_prof_expires, it_virt_expires;
528	cputime_t it_prof_incr, it_virt_incr;
529
530	/*
531	 * Thread group totals for process CPU timers.
532	 * See thread_group_cputimer(), et al, for details.
533	 */
534	struct thread_group_cputimer cputimer;
535
536	/* Earliest-expiration cache. */
537	struct task_cputime cputime_expires;
538
539	struct list_head cpu_timers[3];
540
541	/* job control IDs */
542
543	/*
544	 * pgrp and session fields are deprecated.
545	 * use the task_session_Xnr and task_pgrp_Xnr routines below
546	 */
547
548	union {
549		pid_t pgrp __deprecated;
550		pid_t __pgrp;
551	};
552
553	struct pid *tty_old_pgrp;
554
555	union {
556		pid_t session __deprecated;
557		pid_t __session;
558	};
559
560	/* boolean value for session group leader */
561	int leader;
562
563	struct tty_struct *tty; /* NULL if no tty */
564
565	/*
566	 * Cumulative resource counters for dead threads in the group,
567	 * and for reaped dead child processes forked by this group.
568	 * Live threads maintain their own counters and add to these
569	 * in __exit_signal, except for the group leader.
570	 */
571	cputime_t utime, stime, cutime, cstime;
572	cputime_t gtime;
573	cputime_t cgtime;
574	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
575	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
576	unsigned long inblock, oublock, cinblock, coublock;
577	struct task_io_accounting ioac;
578
579	/*
580	 * Cumulative ns of schedule CPU time fo dead threads in the
581	 * group, not including a zombie group leader, (This only differs
582	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
583	 * other than jiffies.)
584	 */
585	unsigned long long sum_sched_runtime;
586
587	/*
588	 * We don't bother to synchronize most readers of this at all,
589	 * because there is no reader checking a limit that actually needs
590	 * to get both rlim_cur and rlim_max atomically, and either one
591	 * alone is a single word that can safely be read normally.
592	 * getrlimit/setrlimit use task_lock(current->group_leader) to
593	 * protect this instead of the siglock, because they really
594	 * have no need to disable irqs.
595	 */
596	struct rlimit rlim[RLIM_NLIMITS];
597
598#ifdef CONFIG_BSD_PROCESS_ACCT
599	struct pacct_struct pacct;	/* per-process accounting information */
600#endif
601#ifdef CONFIG_TASKSTATS
602	struct taskstats *stats;
603#endif
604#ifdef CONFIG_AUDIT
605	unsigned audit_tty;
606	struct tty_audit_buf *tty_audit_buf;
607#endif
608};
609
610/* Context switch must be unlocked if interrupts are to be enabled */
611#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
612# define __ARCH_WANT_UNLOCKED_CTXSW
613#endif
614
615/*
616 * Bits in flags field of signal_struct.
617 */
618#define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
619#define SIGNAL_STOP_DEQUEUED	0x00000002 /* stop signal dequeued */
620#define SIGNAL_STOP_CONTINUED	0x00000004 /* SIGCONT since WCONTINUED reap */
621#define SIGNAL_GROUP_EXIT	0x00000008 /* group exit in progress */
622/*
623 * Pending notifications to parent.
624 */
625#define SIGNAL_CLD_STOPPED	0x00000010
626#define SIGNAL_CLD_CONTINUED	0x00000020
627#define SIGNAL_CLD_MASK		(SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
628
629#define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */
630
631/* If true, all threads except ->group_exit_task have pending SIGKILL */
632static inline int signal_group_exit(const struct signal_struct *sig)
633{
634	return	(sig->flags & SIGNAL_GROUP_EXIT) ||
635		(sig->group_exit_task != NULL);
636}
637
638/*
639 * Some day this will be a full-fledged user tracking system..
640 */
641struct user_struct {
642	atomic_t __count;	/* reference count */
643	atomic_t processes;	/* How many processes does this user have? */
644	atomic_t files;		/* How many open files does this user have? */
645	atomic_t sigpending;	/* How many pending signals does this user have? */
646#ifdef CONFIG_INOTIFY_USER
647	atomic_t inotify_watches; /* How many inotify watches does this user have? */
648	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
649#endif
650#ifdef CONFIG_EPOLL
651	atomic_t epoll_watches;	/* The number of file descriptors currently watched */
652#endif
653#ifdef CONFIG_POSIX_MQUEUE
654	/* protected by mq_lock	*/
655	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
656#endif
657	unsigned long locked_shm; /* How many pages of mlocked shm ? */
658
659#ifdef CONFIG_KEYS
660	struct key *uid_keyring;	/* UID specific keyring */
661	struct key *session_keyring;	/* UID's default session keyring */
662#endif
663
664	/* Hash table maintenance information */
665	struct hlist_node uidhash_node;
666	uid_t uid;
667	struct user_namespace *user_ns;
668
669#ifdef CONFIG_USER_SCHED
670	struct task_group *tg;
671#ifdef CONFIG_SYSFS
672	struct kobject kobj;
673	struct work_struct work;
674#endif
675#endif
676};
677
678extern int uids_sysfs_init(void);
679
680extern struct user_struct *find_user(uid_t);
681
682extern struct user_struct root_user;
683#define INIT_USER (&root_user)
684
685
686struct backing_dev_info;
687struct reclaim_state;
688
689#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
690struct sched_info {
691	/* cumulative counters */
692	unsigned long pcount;	      /* # of times run on this cpu */
693	unsigned long long run_delay; /* time spent waiting on a runqueue */
694
695	/* timestamps */
696	unsigned long long last_arrival,/* when we last ran on a cpu */
697			   last_queued;	/* when we were last queued to run */
698#ifdef CONFIG_SCHEDSTATS
699	/* BKL stats */
700	unsigned int bkl_count;
701#endif
702};
703#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
704
705#ifdef CONFIG_TASK_DELAY_ACCT
706struct task_delay_info {
707	spinlock_t	lock;
708	unsigned int	flags;	/* Private per-task flags */
709
710	/* For each stat XXX, add following, aligned appropriately
711	 *
712	 * struct timespec XXX_start, XXX_end;
713	 * u64 XXX_delay;
714	 * u32 XXX_count;
715	 *
716	 * Atomicity of updates to XXX_delay, XXX_count protected by
717	 * single lock above (split into XXX_lock if contention is an issue).
718	 */
719
720	/*
721	 * XXX_count is incremented on every XXX operation, the delay
722	 * associated with the operation is added to XXX_delay.
723	 * XXX_delay contains the accumulated delay time in nanoseconds.
724	 */
725	struct timespec blkio_start, blkio_end;	/* Shared by blkio, swapin */
726	u64 blkio_delay;	/* wait for sync block io completion */
727	u64 swapin_delay;	/* wait for swapin block io completion */
728	u32 blkio_count;	/* total count of the number of sync block */
729				/* io operations performed */
730	u32 swapin_count;	/* total count of the number of swapin block */
731				/* io operations performed */
732
733	struct timespec freepages_start, freepages_end;
734	u64 freepages_delay;	/* wait for memory reclaim */
735	u32 freepages_count;	/* total count of memory reclaim */
736};
737#endif	/* CONFIG_TASK_DELAY_ACCT */
738
739static inline int sched_info_on(void)
740{
741#ifdef CONFIG_SCHEDSTATS
742	return 1;
743#elif defined(CONFIG_TASK_DELAY_ACCT)
744	extern int delayacct_on;
745	return delayacct_on;
746#else
747	return 0;
748#endif
749}
750
751enum cpu_idle_type {
752	CPU_IDLE,
753	CPU_NOT_IDLE,
754	CPU_NEWLY_IDLE,
755	CPU_MAX_IDLE_TYPES
756};
757
758/*
759 * sched-domains (multiprocessor balancing) declarations:
760 */
761
762/*
763 * Increase resolution of nice-level calculations:
764 */
765#define SCHED_LOAD_SHIFT	10
766#define SCHED_LOAD_SCALE	(1L << SCHED_LOAD_SHIFT)
767
768#define SCHED_LOAD_SCALE_FUZZ	SCHED_LOAD_SCALE
769
770#ifdef CONFIG_SMP
771#define SD_LOAD_BALANCE		1	/* Do load balancing on this domain. */
772#define SD_BALANCE_NEWIDLE	2	/* Balance when about to become idle */
773#define SD_BALANCE_EXEC		4	/* Balance on exec */
774#define SD_BALANCE_FORK		8	/* Balance on fork, clone */
775#define SD_WAKE_IDLE		16	/* Wake to idle CPU on task wakeup */
776#define SD_WAKE_AFFINE		32	/* Wake task to waking CPU */
777#define SD_WAKE_BALANCE		64	/* Perform balancing at task wakeup */
778#define SD_SHARE_CPUPOWER	128	/* Domain members share cpu power */
779#define SD_POWERSAVINGS_BALANCE	256	/* Balance for power savings */
780#define SD_SHARE_PKG_RESOURCES	512	/* Domain members share cpu pkg resources */
781#define SD_SERIALIZE		1024	/* Only a single load balancing instance */
782#define SD_WAKE_IDLE_FAR	2048	/* Gain latency sacrificing cache hit */
783
784enum powersavings_balance_level {
785	POWERSAVINGS_BALANCE_NONE = 0,  /* No power saving load balance */
786	POWERSAVINGS_BALANCE_BASIC,	/* Fill one thread/core/package
787					 * first for long running threads
788					 */
789	POWERSAVINGS_BALANCE_WAKEUP,	/* Also bias task wakeups to semi-idle
790					 * cpu package for power savings
791					 */
792	MAX_POWERSAVINGS_BALANCE_LEVELS
793};
794
795extern int sched_mc_power_savings, sched_smt_power_savings;
796
797static inline int sd_balance_for_mc_power(void)
798{
799	if (sched_smt_power_savings)
800		return SD_POWERSAVINGS_BALANCE;
801
802	return 0;
803}
804
805static inline int sd_balance_for_package_power(void)
806{
807	if (sched_mc_power_savings | sched_smt_power_savings)
808		return SD_POWERSAVINGS_BALANCE;
809
810	return 0;
811}
812
813/*
814 * Optimise SD flags for power savings:
815 * SD_BALANCE_NEWIDLE helps agressive task consolidation and power savings.
816 * Keep default SD flags if sched_{smt,mc}_power_saving=0
817 */
818
819static inline int sd_power_saving_flags(void)
820{
821	if (sched_mc_power_savings | sched_smt_power_savings)
822		return SD_BALANCE_NEWIDLE;
823
824	return 0;
825}
826
827struct sched_group {
828	struct sched_group *next;	/* Must be a circular list */
829
830	/*
831	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
832	 * single CPU. This is read only (except for setup, hotplug CPU).
833	 * Note : Never change cpu_power without recompute its reciprocal
834	 */
835	unsigned int __cpu_power;
836	/*
837	 * reciprocal value of cpu_power to avoid expensive divides
838	 * (see include/linux/reciprocal_div.h)
839	 */
840	u32 reciprocal_cpu_power;
841
842	unsigned long cpumask[];
843};
844
845static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
846{
847	return to_cpumask(sg->cpumask);
848}
849
850enum sched_domain_level {
851	SD_LV_NONE = 0,
852	SD_LV_SIBLING,
853	SD_LV_MC,
854	SD_LV_CPU,
855	SD_LV_NODE,
856	SD_LV_ALLNODES,
857	SD_LV_MAX
858};
859
860struct sched_domain_attr {
861	int relax_domain_level;
862};
863
864#define SD_ATTR_INIT	(struct sched_domain_attr) {	\
865	.relax_domain_level = -1,			\
866}
867
868struct sched_domain {
869	/* These fields must be setup */
870	struct sched_domain *parent;	/* top domain must be null terminated */
871	struct sched_domain *child;	/* bottom domain must be null terminated */
872	struct sched_group *groups;	/* the balancing groups of the domain */
873	unsigned long min_interval;	/* Minimum balance interval ms */
874	unsigned long max_interval;	/* Maximum balance interval ms */
875	unsigned int busy_factor;	/* less balancing by factor if busy */
876	unsigned int imbalance_pct;	/* No balance until over watermark */
877	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
878	unsigned int busy_idx;
879	unsigned int idle_idx;
880	unsigned int newidle_idx;
881	unsigned int wake_idx;
882	unsigned int forkexec_idx;
883	int flags;			/* See SD_* */
884	enum sched_domain_level level;
885
886	/* Runtime fields. */
887	unsigned long last_balance;	/* init to jiffies. units in jiffies */
888	unsigned int balance_interval;	/* initialise to 1. units in ms. */
889	unsigned int nr_balance_failed; /* initialise to 0 */
890
891	u64 last_update;
892
893#ifdef CONFIG_SCHEDSTATS
894	/* load_balance() stats */
895	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
896	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
897	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
898	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
899	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
900	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
901	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
902	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
903
904	/* Active load balancing */
905	unsigned int alb_count;
906	unsigned int alb_failed;
907	unsigned int alb_pushed;
908
909	/* SD_BALANCE_EXEC stats */
910	unsigned int sbe_count;
911	unsigned int sbe_balanced;
912	unsigned int sbe_pushed;
913
914	/* SD_BALANCE_FORK stats */
915	unsigned int sbf_count;
916	unsigned int sbf_balanced;
917	unsigned int sbf_pushed;
918
919	/* try_to_wake_up() stats */
920	unsigned int ttwu_wake_remote;
921	unsigned int ttwu_move_affine;
922	unsigned int ttwu_move_balance;
923#endif
924#ifdef CONFIG_SCHED_DEBUG
925	char *name;
926#endif
927
928	/* span of all CPUs in this domain */
929	unsigned long span[];
930};
931
932static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
933{
934	return to_cpumask(sd->span);
935}
936
937extern void partition_sched_domains(int ndoms_new, struct cpumask *doms_new,
938				    struct sched_domain_attr *dattr_new);
939
940/* Test a flag in parent sched domain */
941static inline int test_sd_parent(struct sched_domain *sd, int flag)
942{
943	if (sd->parent && (sd->parent->flags & flag))
944		return 1;
945
946	return 0;
947}
948
949#else /* CONFIG_SMP */
950
951struct sched_domain_attr;
952
953static inline void
954partition_sched_domains(int ndoms_new, struct cpumask *doms_new,
955			struct sched_domain_attr *dattr_new)
956{
957}
958#endif	/* !CONFIG_SMP */
959
960struct io_context;			/* See blkdev.h */
961
962
963#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
964extern void prefetch_stack(struct task_struct *t);
965#else
966static inline void prefetch_stack(struct task_struct *t) { }
967#endif
968
969struct audit_context;		/* See audit.c */
970struct mempolicy;
971struct pipe_inode_info;
972struct uts_namespace;
973
974struct rq;
975struct sched_domain;
976
977struct sched_class {
978	const struct sched_class *next;
979
980	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int wakeup);
981	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int sleep);
982	void (*yield_task) (struct rq *rq);
983
984	void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int sync);
985
986	struct task_struct * (*pick_next_task) (struct rq *rq);
987	void (*put_prev_task) (struct rq *rq, struct task_struct *p);
988
989#ifdef CONFIG_SMP
990	int  (*select_task_rq)(struct task_struct *p, int sync);
991
992	unsigned long (*load_balance) (struct rq *this_rq, int this_cpu,
993			struct rq *busiest, unsigned long max_load_move,
994			struct sched_domain *sd, enum cpu_idle_type idle,
995			int *all_pinned, int *this_best_prio);
996
997	int (*move_one_task) (struct rq *this_rq, int this_cpu,
998			      struct rq *busiest, struct sched_domain *sd,
999			      enum cpu_idle_type idle);
1000	void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
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
1027struct 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 */
1041struct 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#ifdef CONFIG_SCHEDSTATS
1056	u64			wait_start;
1057	u64			wait_max;
1058	u64			wait_count;
1059	u64			wait_sum;
1060
1061	u64			sleep_start;
1062	u64			sleep_max;
1063	s64			sum_sleep_runtime;
1064
1065	u64			block_start;
1066	u64			block_max;
1067	u64			exec_max;
1068	u64			slice_max;
1069
1070	u64			nr_migrations;
1071	u64			nr_migrations_cold;
1072	u64			nr_failed_migrations_affine;
1073	u64			nr_failed_migrations_running;
1074	u64			nr_failed_migrations_hot;
1075	u64			nr_forced_migrations;
1076	u64			nr_forced2_migrations;
1077
1078	u64			nr_wakeups;
1079	u64			nr_wakeups_sync;
1080	u64			nr_wakeups_migrate;
1081	u64			nr_wakeups_local;
1082	u64			nr_wakeups_remote;
1083	u64			nr_wakeups_affine;
1084	u64			nr_wakeups_affine_attempts;
1085	u64			nr_wakeups_passive;
1086	u64			nr_wakeups_idle;
1087#endif
1088
1089#ifdef CONFIG_FAIR_GROUP_SCHED
1090	struct sched_entity	*parent;
1091	/* rq on which this entity is (to be) queued: */
1092	struct cfs_rq		*cfs_rq;
1093	/* rq "owned" by this entity/group: */
1094	struct cfs_rq		*my_q;
1095#endif
1096};
1097
1098struct sched_rt_entity {
1099	struct list_head run_list;
1100	unsigned long timeout;
1101	unsigned int time_slice;
1102	int nr_cpus_allowed;
1103
1104	struct sched_rt_entity *back;
1105#ifdef CONFIG_RT_GROUP_SCHED
1106	struct sched_rt_entity	*parent;
1107	/* rq on which this entity is (to be) queued: */
1108	struct rt_rq		*rt_rq;
1109	/* rq "owned" by this entity/group: */
1110	struct rt_rq		*my_q;
1111#endif
1112};
1113
1114struct task_struct {
1115	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
1116	void *stack;
1117	atomic_t usage;
1118	unsigned int flags;	/* per process flags, defined below */
1119	unsigned int ptrace;
1120
1121	int lock_depth;		/* BKL lock depth */
1122
1123#ifdef CONFIG_SMP
1124#ifdef __ARCH_WANT_UNLOCKED_CTXSW
1125	int oncpu;
1126#endif
1127#endif
1128
1129	int prio, static_prio, normal_prio;
1130	unsigned int rt_priority;
1131	const struct sched_class *sched_class;
1132	struct sched_entity se;
1133	struct sched_rt_entity rt;
1134
1135#ifdef CONFIG_PREEMPT_NOTIFIERS
1136	/* list of struct preempt_notifier: */
1137	struct hlist_head preempt_notifiers;
1138#endif
1139
1140	/*
1141	 * fpu_counter contains the number of consecutive context switches
1142	 * that the FPU is used. If this is over a threshold, the lazy fpu
1143	 * saving becomes unlazy to save the trap. This is an unsigned char
1144	 * so that after 256 times the counter wraps and the behavior turns
1145	 * lazy again; this to deal with bursty apps that only use FPU for
1146	 * a short time
1147	 */
1148	unsigned char fpu_counter;
1149	s8 oomkilladj; /* OOM kill score adjustment (bit shift). */
1150#ifdef CONFIG_BLK_DEV_IO_TRACE
1151	unsigned int btrace_seq;
1152#endif
1153
1154	unsigned int policy;
1155	cpumask_t cpus_allowed;
1156
1157#ifdef CONFIG_PREEMPT_RCU
1158	int rcu_read_lock_nesting;
1159	int rcu_flipctr_idx;
1160#endif /* #ifdef CONFIG_PREEMPT_RCU */
1161
1162#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1163	struct sched_info sched_info;
1164#endif
1165
1166	struct list_head tasks;
1167
1168	struct mm_struct *mm, *active_mm;
1169
1170/* task state */
1171	struct linux_binfmt *binfmt;
1172	int exit_state;
1173	int exit_code, exit_signal;
1174	int pdeath_signal;  /*  The signal sent when the parent dies  */
1175	/* ??? */
1176	unsigned int personality;
1177	unsigned did_exec:1;
1178	pid_t pid;
1179	pid_t tgid;
1180
1181#ifdef CONFIG_CC_STACKPROTECTOR
1182	/* Canary value for the -fstack-protector gcc feature */
1183	unsigned long stack_canary;
1184#endif
1185	/*
1186	 * pointers to (original) parent process, youngest child, younger sibling,
1187	 * older sibling, respectively.  (p->father can be replaced with
1188	 * p->real_parent->pid)
1189	 */
1190	struct task_struct *real_parent; /* real parent process */
1191	struct task_struct *parent; /* recipient of SIGCHLD, wait4() reports */
1192	/*
1193	 * children/sibling forms the list of my natural children
1194	 */
1195	struct list_head children;	/* list of my children */
1196	struct list_head sibling;	/* linkage in my parent's children list */
1197	struct task_struct *group_leader;	/* threadgroup leader */
1198
1199	/*
1200	 * ptraced is the list of tasks this task is using ptrace on.
1201	 * This includes both natural children and PTRACE_ATTACH targets.
1202	 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1203	 */
1204	struct list_head ptraced;
1205	struct list_head ptrace_entry;
1206
1207#ifdef CONFIG_X86_PTRACE_BTS
1208	/*
1209	 * This is the tracer handle for the ptrace BTS extension.
1210	 * This field actually belongs to the ptracer task.
1211	 */
1212	struct bts_tracer *bts;
1213	/*
1214	 * The buffer to hold the BTS data.
1215	 */
1216	void *bts_buffer;
1217	size_t bts_size;
1218#endif /* CONFIG_X86_PTRACE_BTS */
1219
1220	/* PID/PID hash table linkage. */
1221	struct pid_link pids[PIDTYPE_MAX];
1222	struct list_head thread_group;
1223
1224	struct completion *vfork_done;		/* for vfork() */
1225	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
1226	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
1227
1228	cputime_t utime, stime, utimescaled, stimescaled;
1229	cputime_t gtime;
1230	cputime_t prev_utime, prev_stime;
1231	unsigned long nvcsw, nivcsw; /* context switch counts */
1232	struct timespec start_time; 		/* monotonic time */
1233	struct timespec real_start_time;	/* boot based time */
1234/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1235	unsigned long min_flt, maj_flt;
1236
1237	struct task_cputime cputime_expires;
1238	struct list_head cpu_timers[3];
1239
1240/* process credentials */
1241	const struct cred *real_cred;	/* objective and real subjective task
1242					 * credentials (COW) */
1243	const struct cred *cred;	/* effective (overridable) subjective task
1244					 * credentials (COW) */
1245	struct mutex cred_exec_mutex;	/* execve vs ptrace cred calculation mutex */
1246
1247	char comm[TASK_COMM_LEN]; /* executable name excluding path
1248				     - access with [gs]et_task_comm (which lock
1249				       it with task_lock())
1250				     - initialized normally by flush_old_exec */
1251/* file system info */
1252	int link_count, total_link_count;
1253#ifdef CONFIG_SYSVIPC
1254/* ipc stuff */
1255	struct sysv_sem sysvsem;
1256#endif
1257#ifdef CONFIG_DETECT_SOFTLOCKUP
1258/* hung task detection */
1259	unsigned long last_switch_timestamp;
1260	unsigned long last_switch_count;
1261#endif
1262/* CPU-specific state of this task */
1263	struct thread_struct thread;
1264/* filesystem information */
1265	struct fs_struct *fs;
1266/* open file information */
1267	struct files_struct *files;
1268/* namespaces */
1269	struct nsproxy *nsproxy;
1270/* signal handlers */
1271	struct signal_struct *signal;
1272	struct sighand_struct *sighand;
1273
1274	sigset_t blocked, real_blocked;
1275	sigset_t saved_sigmask;	/* restored if set_restore_sigmask() was used */
1276	struct sigpending pending;
1277
1278	unsigned long sas_ss_sp;
1279	size_t sas_ss_size;
1280	int (*notifier)(void *priv);
1281	void *notifier_data;
1282	sigset_t *notifier_mask;
1283	struct audit_context *audit_context;
1284#ifdef CONFIG_AUDITSYSCALL
1285	uid_t loginuid;
1286	unsigned int sessionid;
1287#endif
1288	seccomp_t seccomp;
1289
1290/* Thread group tracking */
1291   	u32 parent_exec_id;
1292   	u32 self_exec_id;
1293/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
1294	spinlock_t alloc_lock;
1295
1296	/* Protection of the PI data structures: */
1297	spinlock_t pi_lock;
1298
1299#ifdef CONFIG_RT_MUTEXES
1300	/* PI waiters blocked on a rt_mutex held by this task */
1301	struct plist_head pi_waiters;
1302	/* Deadlock detection and priority inheritance handling */
1303	struct rt_mutex_waiter *pi_blocked_on;
1304#endif
1305
1306#ifdef CONFIG_DEBUG_MUTEXES
1307	/* mutex deadlock detection */
1308	struct mutex_waiter *blocked_on;
1309#endif
1310#ifdef CONFIG_TRACE_IRQFLAGS
1311	unsigned int irq_events;
1312	int hardirqs_enabled;
1313	unsigned long hardirq_enable_ip;
1314	unsigned int hardirq_enable_event;
1315	unsigned long hardirq_disable_ip;
1316	unsigned int hardirq_disable_event;
1317	int softirqs_enabled;
1318	unsigned long softirq_disable_ip;
1319	unsigned int softirq_disable_event;
1320	unsigned long softirq_enable_ip;
1321	unsigned int softirq_enable_event;
1322	int hardirq_context;
1323	int softirq_context;
1324#endif
1325#ifdef CONFIG_LOCKDEP
1326# define MAX_LOCK_DEPTH 48UL
1327	u64 curr_chain_key;
1328	int lockdep_depth;
1329	unsigned int lockdep_recursion;
1330	struct held_lock held_locks[MAX_LOCK_DEPTH];
1331#endif
1332
1333/* journalling filesystem info */
1334	void *journal_info;
1335
1336/* stacked block device info */
1337	struct bio *bio_list, **bio_tail;
1338
1339/* VM state */
1340	struct reclaim_state *reclaim_state;
1341
1342	struct backing_dev_info *backing_dev_info;
1343
1344	struct io_context *io_context;
1345
1346	unsigned long ptrace_message;
1347	siginfo_t *last_siginfo; /* For ptrace use.  */
1348	struct task_io_accounting ioac;
1349#if defined(CONFIG_TASK_XACCT)
1350	u64 acct_rss_mem1;	/* accumulated rss usage */
1351	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1352	cputime_t acct_timexpd;	/* stime + utime since last update */
1353#endif
1354#ifdef CONFIG_CPUSETS
1355	nodemask_t mems_allowed;
1356	int cpuset_mems_generation;
1357	int cpuset_mem_spread_rotor;
1358#endif
1359#ifdef CONFIG_CGROUPS
1360	/* Control Group info protected by css_set_lock */
1361	struct css_set *cgroups;
1362	/* cg_list protected by css_set_lock and tsk->alloc_lock */
1363	struct list_head cg_list;
1364#endif
1365#ifdef CONFIG_FUTEX
1366	struct robust_list_head __user *robust_list;
1367#ifdef CONFIG_COMPAT
1368	struct compat_robust_list_head __user *compat_robust_list;
1369#endif
1370	struct list_head pi_state_list;
1371	struct futex_pi_state *pi_state_cache;
1372#endif
1373#ifdef CONFIG_NUMA
1374	struct mempolicy *mempolicy;
1375	short il_next;
1376#endif
1377	atomic_t fs_excl;	/* holding fs exclusive resources */
1378	struct rcu_head rcu;
1379
1380	/*
1381	 * cache last used pipe for splice
1382	 */
1383	struct pipe_inode_info *splice_pipe;
1384#ifdef	CONFIG_TASK_DELAY_ACCT
1385	struct task_delay_info *delays;
1386#endif
1387#ifdef CONFIG_FAULT_INJECTION
1388	int make_it_fail;
1389#endif
1390	struct prop_local_single dirties;
1391#ifdef CONFIG_LATENCYTOP
1392	int latency_record_count;
1393	struct latency_record latency_record[LT_SAVECOUNT];
1394#endif
1395	/*
1396	 * time slack values; these are used to round up poll() and
1397	 * select() etc timeout values. These are in nanoseconds.
1398	 */
1399	unsigned long timer_slack_ns;
1400	unsigned long default_timer_slack_ns;
1401
1402	struct list_head	*scm_work_list;
1403#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1404	/* Index of current stored adress in ret_stack */
1405	int curr_ret_stack;
1406	/* Stack of return addresses for return function tracing */
1407	struct ftrace_ret_stack	*ret_stack;
1408	/*
1409	 * Number of functions that haven't been traced
1410	 * because of depth overrun.
1411	 */
1412	atomic_t trace_overrun;
1413	/* Pause for the tracing */
1414	atomic_t tracing_graph_pause;
1415#endif
1416#ifdef CONFIG_TRACING
1417	/* state flags for use by tracers */
1418	unsigned long trace;
1419#endif
1420};
1421
1422/*
1423 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1424 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1425 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1426 * values are inverted: lower p->prio value means higher priority.
1427 *
1428 * The MAX_USER_RT_PRIO value allows the actual maximum
1429 * RT priority to be separate from the value exported to
1430 * user-space.  This allows kernel threads to set their
1431 * priority to a value higher than any user task. Note:
1432 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1433 */
1434
1435#define MAX_USER_RT_PRIO	100
1436#define MAX_RT_PRIO		MAX_USER_RT_PRIO
1437
1438#define MAX_PRIO		(MAX_RT_PRIO + 40)
1439#define DEFAULT_PRIO		(MAX_RT_PRIO + 20)
1440
1441static inline int rt_prio(int prio)
1442{
1443	if (unlikely(prio < MAX_RT_PRIO))
1444		return 1;
1445	return 0;
1446}
1447
1448static inline int rt_task(struct task_struct *p)
1449{
1450	return rt_prio(p->prio);
1451}
1452
1453static inline void set_task_session(struct task_struct *tsk, pid_t session)
1454{
1455	tsk->signal->__session = session;
1456}
1457
1458static inline void set_task_pgrp(struct task_struct *tsk, pid_t pgrp)
1459{
1460	tsk->signal->__pgrp = pgrp;
1461}
1462
1463static inline struct pid *task_pid(struct task_struct *task)
1464{
1465	return task->pids[PIDTYPE_PID].pid;
1466}
1467
1468static inline struct pid *task_tgid(struct task_struct *task)
1469{
1470	return task->group_leader->pids[PIDTYPE_PID].pid;
1471}
1472
1473static inline struct pid *task_pgrp(struct task_struct *task)
1474{
1475	return task->group_leader->pids[PIDTYPE_PGID].pid;
1476}
1477
1478static inline struct pid *task_session(struct task_struct *task)
1479{
1480	return task->group_leader->pids[PIDTYPE_SID].pid;
1481}
1482
1483struct pid_namespace;
1484
1485/*
1486 * the helpers to get the task's different pids as they are seen
1487 * from various namespaces
1488 *
1489 * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1490 * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1491 *                     current.
1492 * task_xid_nr_ns()  : id seen from the ns specified;
1493 *
1494 * set_task_vxid()   : assigns a virtual id to a task;
1495 *
1496 * see also pid_nr() etc in include/linux/pid.h
1497 */
1498
1499static inline pid_t task_pid_nr(struct task_struct *tsk)
1500{
1501	return tsk->pid;
1502}
1503
1504pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1505
1506static inline pid_t task_pid_vnr(struct task_struct *tsk)
1507{
1508	return pid_vnr(task_pid(tsk));
1509}
1510
1511
1512static inline pid_t task_tgid_nr(struct task_struct *tsk)
1513{
1514	return tsk->tgid;
1515}
1516
1517pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1518
1519static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1520{
1521	return pid_vnr(task_tgid(tsk));
1522}
1523
1524
1525static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1526{
1527	return tsk->signal->__pgrp;
1528}
1529
1530pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1531
1532static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1533{
1534	return pid_vnr(task_pgrp(tsk));
1535}
1536
1537
1538static inline pid_t task_session_nr(struct task_struct *tsk)
1539{
1540	return tsk->signal->__session;
1541}
1542
1543pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1544
1545static inline pid_t task_session_vnr(struct task_struct *tsk)
1546{
1547	return pid_vnr(task_session(tsk));
1548}
1549
1550
1551/**
1552 * pid_alive - check that a task structure is not stale
1553 * @p: Task structure to be checked.
1554 *
1555 * Test if a process is not yet dead (at most zombie state)
1556 * If pid_alive fails, then pointers within the task structure
1557 * can be stale and must not be dereferenced.
1558 */
1559static inline int pid_alive(struct task_struct *p)
1560{
1561	return p->pids[PIDTYPE_PID].pid != NULL;
1562}
1563
1564/**
1565 * is_global_init - check if a task structure is init
1566 * @tsk: Task structure to be checked.
1567 *
1568 * Check if a task structure is the first user space task the kernel created.
1569 */
1570static inline int is_global_init(struct task_struct *tsk)
1571{
1572	return tsk->pid == 1;
1573}
1574
1575/*
1576 * is_container_init:
1577 * check whether in the task is init in its own pid namespace.
1578 */
1579extern int is_container_init(struct task_struct *tsk);
1580
1581extern struct pid *cad_pid;
1582
1583extern void free_task(struct task_struct *tsk);
1584#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1585
1586extern void __put_task_struct(struct task_struct *t);
1587
1588static inline void put_task_struct(struct task_struct *t)
1589{
1590	if (atomic_dec_and_test(&t->usage))
1591		__put_task_struct(t);
1592}
1593
1594extern cputime_t task_utime(struct task_struct *p);
1595extern cputime_t task_stime(struct task_struct *p);
1596extern cputime_t task_gtime(struct task_struct *p);
1597
1598/*
1599 * Per process flags
1600 */
1601#define PF_ALIGNWARN	0x00000001	/* Print alignment warning msgs */
1602					/* Not implemented yet, only for 486*/
1603#define PF_STARTING	0x00000002	/* being created */
1604#define PF_EXITING	0x00000004	/* getting shut down */
1605#define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
1606#define PF_VCPU		0x00000010	/* I'm a virtual CPU */
1607#define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
1608#define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
1609#define PF_DUMPCORE	0x00000200	/* dumped core */
1610#define PF_SIGNALED	0x00000400	/* killed by a signal */
1611#define PF_MEMALLOC	0x00000800	/* Allocating memory */
1612#define PF_FLUSHER	0x00001000	/* responsible for disk writeback */
1613#define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
1614#define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
1615#define PF_FROZEN	0x00010000	/* frozen for system suspend */
1616#define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
1617#define PF_KSWAPD	0x00040000	/* I am kswapd */
1618#define PF_SWAPOFF	0x00080000	/* I am in swapoff */
1619#define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
1620#define PF_KTHREAD	0x00200000	/* I am a kernel thread */
1621#define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
1622#define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
1623#define PF_SPREAD_PAGE	0x01000000	/* Spread page cache over cpuset */
1624#define PF_SPREAD_SLAB	0x02000000	/* Spread some slab caches over cpuset */
1625#define PF_THREAD_BOUND	0x04000000	/* Thread bound to specific cpu */
1626#define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
1627#define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
1628#define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezeable */
1629#define PF_FREEZER_NOSIG 0x80000000	/* Freezer won't send signals to it */
1630
1631/*
1632 * Only the _current_ task can read/write to tsk->flags, but other
1633 * tasks can access tsk->flags in readonly mode for example
1634 * with tsk_used_math (like during threaded core dumping).
1635 * There is however an exception to this rule during ptrace
1636 * or during fork: the ptracer task is allowed to write to the
1637 * child->flags of its traced child (same goes for fork, the parent
1638 * can write to the child->flags), because we're guaranteed the
1639 * child is not running and in turn not changing child->flags
1640 * at the same time the parent does it.
1641 */
1642#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1643#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1644#define clear_used_math() clear_stopped_child_used_math(current)
1645#define set_used_math() set_stopped_child_used_math(current)
1646#define conditional_stopped_child_used_math(condition, child) \
1647	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1648#define conditional_used_math(condition) \
1649	conditional_stopped_child_used_math(condition, current)
1650#define copy_to_stopped_child_used_math(child) \
1651	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1652/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1653#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1654#define used_math() tsk_used_math(current)
1655
1656#ifdef CONFIG_SMP
1657extern int set_cpus_allowed_ptr(struct task_struct *p,
1658				const struct cpumask *new_mask);
1659#else
1660static inline int set_cpus_allowed_ptr(struct task_struct *p,
1661				       const struct cpumask *new_mask)
1662{
1663	if (!cpumask_test_cpu(0, new_mask))
1664		return -EINVAL;
1665	return 0;
1666}
1667#endif
1668static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1669{
1670	return set_cpus_allowed_ptr(p, &new_mask);
1671}
1672
1673extern unsigned long long sched_clock(void);
1674
1675extern void sched_clock_init(void);
1676extern u64 sched_clock_cpu(int cpu);
1677
1678#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1679static inline void sched_clock_tick(void)
1680{
1681}
1682
1683static inline void sched_clock_idle_sleep_event(void)
1684{
1685}
1686
1687static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
1688{
1689}
1690#else
1691extern void sched_clock_tick(void);
1692extern void sched_clock_idle_sleep_event(void);
1693extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1694#endif
1695
1696/*
1697 * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
1698 * clock constructed from sched_clock():
1699 */
1700extern unsigned long long cpu_clock(int cpu);
1701
1702extern unsigned long long
1703task_sched_runtime(struct task_struct *task);
1704extern unsigned long long thread_group_sched_runtime(struct task_struct *task);
1705
1706/* sched_exec is called by processes performing an exec */
1707#ifdef CONFIG_SMP
1708extern void sched_exec(void);
1709#else
1710#define sched_exec()   {}
1711#endif
1712
1713extern void sched_clock_idle_sleep_event(void);
1714extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1715
1716#ifdef CONFIG_HOTPLUG_CPU
1717extern void idle_task_exit(void);
1718#else
1719static inline void idle_task_exit(void) {}
1720#endif
1721
1722extern void sched_idle_next(void);
1723
1724#if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
1725extern void wake_up_idle_cpu(int cpu);
1726#else
1727static inline void wake_up_idle_cpu(int cpu) { }
1728#endif
1729
1730extern unsigned int sysctl_sched_latency;
1731extern unsigned int sysctl_sched_min_granularity;
1732extern unsigned int sysctl_sched_wakeup_granularity;
1733extern unsigned int sysctl_sched_shares_ratelimit;
1734extern unsigned int sysctl_sched_shares_thresh;
1735#ifdef CONFIG_SCHED_DEBUG
1736extern unsigned int sysctl_sched_child_runs_first;
1737extern unsigned int sysctl_sched_features;
1738extern unsigned int sysctl_sched_migration_cost;
1739extern unsigned int sysctl_sched_nr_migrate;
1740
1741int sched_nr_latency_handler(struct ctl_table *table, int write,
1742		struct file *file, void __user *buffer, size_t *length,
1743		loff_t *ppos);
1744#endif
1745extern unsigned int sysctl_sched_rt_period;
1746extern int sysctl_sched_rt_runtime;
1747
1748int sched_rt_handler(struct ctl_table *table, int write,
1749		struct file *filp, void __user *buffer, size_t *lenp,
1750		loff_t *ppos);
1751
1752extern unsigned int sysctl_sched_compat_yield;
1753
1754#ifdef CONFIG_RT_MUTEXES
1755extern int rt_mutex_getprio(struct task_struct *p);
1756extern void rt_mutex_setprio(struct task_struct *p, int prio);
1757extern void rt_mutex_adjust_pi(struct task_struct *p);
1758#else
1759static inline int rt_mutex_getprio(struct task_struct *p)
1760{
1761	return p->normal_prio;
1762}
1763# define rt_mutex_adjust_pi(p)		do { } while (0)
1764#endif
1765
1766extern void set_user_nice(struct task_struct *p, long nice);
1767extern int task_prio(const struct task_struct *p);
1768extern int task_nice(const struct task_struct *p);
1769extern int can_nice(const struct task_struct *p, const int nice);
1770extern int task_curr(const struct task_struct *p);
1771extern int idle_cpu(int cpu);
1772extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1773extern int sched_setscheduler_nocheck(struct task_struct *, int,
1774				      struct sched_param *);
1775extern struct task_struct *idle_task(int cpu);
1776extern struct task_struct *curr_task(int cpu);
1777extern void set_curr_task(int cpu, struct task_struct *p);
1778
1779void yield(void);
1780
1781/*
1782 * The default (Linux) execution domain.
1783 */
1784extern struct exec_domain	default_exec_domain;
1785
1786union thread_union {
1787	struct thread_info thread_info;
1788	unsigned long stack[THREAD_SIZE/sizeof(long)];
1789};
1790
1791#ifndef __HAVE_ARCH_KSTACK_END
1792static inline int kstack_end(void *addr)
1793{
1794	/* Reliable end of stack detection:
1795	 * Some APM bios versions misalign the stack
1796	 */
1797	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1798}
1799#endif
1800
1801extern union thread_union init_thread_union;
1802extern struct task_struct init_task;
1803
1804extern struct   mm_struct init_mm;
1805
1806extern struct pid_namespace init_pid_ns;
1807
1808/*
1809 * find a task by one of its numerical ids
1810 *
1811 * find_task_by_pid_type_ns():
1812 *      it is the most generic call - it finds a task by all id,
1813 *      type and namespace specified
1814 * find_task_by_pid_ns():
1815 *      finds a task by its pid in the specified namespace
1816 * find_task_by_vpid():
1817 *      finds a task by its virtual pid
1818 *
1819 * see also find_vpid() etc in include/linux/pid.h
1820 */
1821
1822extern struct task_struct *find_task_by_pid_type_ns(int type, int pid,
1823		struct pid_namespace *ns);
1824
1825extern struct task_struct *find_task_by_vpid(pid_t nr);
1826extern struct task_struct *find_task_by_pid_ns(pid_t nr,
1827		struct pid_namespace *ns);
1828
1829extern void __set_special_pids(struct pid *pid);
1830
1831/* per-UID process charging. */
1832extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
1833static inline struct user_struct *get_uid(struct user_struct *u)
1834{
1835	atomic_inc(&u->__count);
1836	return u;
1837}
1838extern void free_uid(struct user_struct *);
1839extern void release_uids(struct user_namespace *ns);
1840
1841#include <asm/current.h>
1842
1843extern void do_timer(unsigned long ticks);
1844
1845extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1846extern int wake_up_process(struct task_struct *tsk);
1847extern void wake_up_new_task(struct task_struct *tsk,
1848				unsigned long clone_flags);
1849#ifdef CONFIG_SMP
1850 extern void kick_process(struct task_struct *tsk);
1851#else
1852 static inline void kick_process(struct task_struct *tsk) { }
1853#endif
1854extern void sched_fork(struct task_struct *p, int clone_flags);
1855extern void sched_dead(struct task_struct *p);
1856
1857extern void proc_caches_init(void);
1858extern void flush_signals(struct task_struct *);
1859extern void ignore_signals(struct task_struct *);
1860extern void flush_signal_handlers(struct task_struct *, int force_default);
1861extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1862
1863static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1864{
1865	unsigned long flags;
1866	int ret;
1867
1868	spin_lock_irqsave(&tsk->sighand->siglock, flags);
1869	ret = dequeue_signal(tsk, mask, info);
1870	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1871
1872	return ret;
1873}
1874
1875extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1876			      sigset_t *mask);
1877extern void unblock_all_signals(void);
1878extern void release_task(struct task_struct * p);
1879extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1880extern int force_sigsegv(int, struct task_struct *);
1881extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1882extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1883extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
1884extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
1885extern int kill_pgrp(struct pid *pid, int sig, int priv);
1886extern int kill_pid(struct pid *pid, int sig, int priv);
1887extern int kill_proc_info(int, struct siginfo *, pid_t);
1888extern int do_notify_parent(struct task_struct *, int);
1889extern void force_sig(int, struct task_struct *);
1890extern void force_sig_specific(int, struct task_struct *);
1891extern int send_sig(int, struct task_struct *, int);
1892extern void zap_other_threads(struct task_struct *p);
1893extern struct sigqueue *sigqueue_alloc(void);
1894extern void sigqueue_free(struct sigqueue *);
1895extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
1896extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
1897extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1898
1899static inline int kill_cad_pid(int sig, int priv)
1900{
1901	return kill_pid(cad_pid, sig, priv);
1902}
1903
1904/* These can be the second arg to send_sig_info/send_group_sig_info.  */
1905#define SEND_SIG_NOINFO ((struct siginfo *) 0)
1906#define SEND_SIG_PRIV	((struct siginfo *) 1)
1907#define SEND_SIG_FORCED	((struct siginfo *) 2)
1908
1909static inline int is_si_special(const struct siginfo *info)
1910{
1911	return info <= SEND_SIG_FORCED;
1912}
1913
1914/* True if we are on the alternate signal stack.  */
1915
1916static inline int on_sig_stack(unsigned long sp)
1917{
1918	return (sp - current->sas_ss_sp < current->sas_ss_size);
1919}
1920
1921static inline int sas_ss_flags(unsigned long sp)
1922{
1923	return (current->sas_ss_size == 0 ? SS_DISABLE
1924		: on_sig_stack(sp) ? SS_ONSTACK : 0);
1925}
1926
1927/*
1928 * Routines for handling mm_structs
1929 */
1930extern struct mm_struct * mm_alloc(void);
1931
1932/* mmdrop drops the mm and the page tables */
1933extern void __mmdrop(struct mm_struct *);
1934static inline void mmdrop(struct mm_struct * mm)
1935{
1936	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
1937		__mmdrop(mm);
1938}
1939
1940/* mmput gets rid of the mappings and all user-space */
1941extern void mmput(struct mm_struct *);
1942/* Grab a reference to a task's mm, if it is not already going away */
1943extern struct mm_struct *get_task_mm(struct task_struct *task);
1944/* Remove the current tasks stale references to the old mm_struct */
1945extern void mm_release(struct task_struct *, struct mm_struct *);
1946/* Allocate a new mm structure and copy contents from tsk->mm */
1947extern struct mm_struct *dup_mm(struct task_struct *tsk);
1948
1949extern int  copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1950extern void flush_thread(void);
1951extern void exit_thread(void);
1952
1953extern void exit_files(struct task_struct *);
1954extern void __cleanup_signal(struct signal_struct *);
1955extern void __cleanup_sighand(struct sighand_struct *);
1956
1957extern void exit_itimers(struct signal_struct *);
1958extern void flush_itimer_signals(void);
1959
1960extern NORET_TYPE void do_group_exit(int);
1961
1962extern void daemonize(const char *, ...);
1963extern int allow_signal(int);
1964extern int disallow_signal(int);
1965
1966extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1967extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1968struct task_struct *fork_idle(int);
1969
1970extern void set_task_comm(struct task_struct *tsk, char *from);
1971extern char *get_task_comm(char *to, struct task_struct *tsk);
1972
1973#ifdef CONFIG_SMP
1974extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
1975#else
1976static inline unsigned long wait_task_inactive(struct task_struct *p,
1977					       long match_state)
1978{
1979	return 1;
1980}
1981#endif
1982
1983#define next_task(p)	list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
1984
1985#define for_each_process(p) \
1986	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1987
1988extern bool is_single_threaded(struct task_struct *);
1989
1990/*
1991 * Careful: do_each_thread/while_each_thread is a double loop so
1992 *          'break' will not work as expected - use goto instead.
1993 */
1994#define do_each_thread(g, t) \
1995	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1996
1997#define while_each_thread(g, t) \
1998	while ((t = next_thread(t)) != g)
1999
2000/* de_thread depends on thread_group_leader not being a pid based check */
2001#define thread_group_leader(p)	(p == p->group_leader)
2002
2003/* Do to the insanities of de_thread it is possible for a process
2004 * to have the pid of the thread group leader without actually being
2005 * the thread group leader.  For iteration through the pids in proc
2006 * all we care about is that we have a task with the appropriate
2007 * pid, we don't actually care if we have the right task.
2008 */
2009static inline int has_group_leader_pid(struct task_struct *p)
2010{
2011	return p->pid == p->tgid;
2012}
2013
2014static inline
2015int same_thread_group(struct task_struct *p1, struct task_struct *p2)
2016{
2017	return p1->tgid == p2->tgid;
2018}
2019
2020static inline struct task_struct *next_thread(const struct task_struct *p)
2021{
2022	return list_entry(rcu_dereference(p->thread_group.next),
2023			  struct task_struct, thread_group);
2024}
2025
2026static inline int thread_group_empty(struct task_struct *p)
2027{
2028	return list_empty(&p->thread_group);
2029}
2030
2031#define delay_group_leader(p) \
2032		(thread_group_leader(p) && !thread_group_empty(p))
2033
2034/*
2035 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2036 * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2037 * pins the final release of task.io_context.  Also protects ->cpuset and
2038 * ->cgroup.subsys[].
2039 *
2040 * Nests both inside and outside of read_lock(&tasklist_lock).
2041 * It must not be nested with write_lock_irq(&tasklist_lock),
2042 * neither inside nor outside.
2043 */
2044static inline void task_lock(struct task_struct *p)
2045{
2046	spin_lock(&p->alloc_lock);
2047}
2048
2049static inline void task_unlock(struct task_struct *p)
2050{
2051	spin_unlock(&p->alloc_lock);
2052}
2053
2054extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2055							unsigned long *flags);
2056
2057static inline void unlock_task_sighand(struct task_struct *tsk,
2058						unsigned long *flags)
2059{
2060	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2061}
2062
2063#ifndef __HAVE_THREAD_FUNCTIONS
2064
2065#define task_thread_info(task)	((struct thread_info *)(task)->stack)
2066#define task_stack_page(task)	((task)->stack)
2067
2068static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2069{
2070	*task_thread_info(p) = *task_thread_info(org);
2071	task_thread_info(p)->task = p;
2072}
2073
2074static inline unsigned long *end_of_stack(struct task_struct *p)
2075{
2076	return (unsigned long *)(task_thread_info(p) + 1);
2077}
2078
2079#endif
2080
2081static inline int object_is_on_stack(void *obj)
2082{
2083	void *stack = task_stack_page(current);
2084
2085	return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2086}
2087
2088extern void thread_info_cache_init(void);
2089
2090/* set thread flags in other task's structures
2091 * - see asm/thread_info.h for TIF_xxxx flags available
2092 */
2093static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2094{
2095	set_ti_thread_flag(task_thread_info(tsk), flag);
2096}
2097
2098static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2099{
2100	clear_ti_thread_flag(task_thread_info(tsk), flag);
2101}
2102
2103static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2104{
2105	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2106}
2107
2108static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2109{
2110	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2111}
2112
2113static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2114{
2115	return test_ti_thread_flag(task_thread_info(tsk), flag);
2116}
2117
2118static inline void set_tsk_need_resched(struct task_struct *tsk)
2119{
2120	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2121}
2122
2123static inline void clear_tsk_need_resched(struct task_struct *tsk)
2124{
2125	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2126}
2127
2128static inline int test_tsk_need_resched(struct task_struct *tsk)
2129{
2130	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2131}
2132
2133static inline int signal_pending(struct task_struct *p)
2134{
2135	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2136}
2137
2138extern int __fatal_signal_pending(struct task_struct *p);
2139
2140static inline int fatal_signal_pending(struct task_struct *p)
2141{
2142	return signal_pending(p) && __fatal_signal_pending(p);
2143}
2144
2145static inline int signal_pending_state(long state, struct task_struct *p)
2146{
2147	if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2148		return 0;
2149	if (!signal_pending(p))
2150		return 0;
2151
2152	return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2153}
2154
2155static inline int need_resched(void)
2156{
2157	return unlikely(test_thread_flag(TIF_NEED_RESCHED));
2158}
2159
2160/*
2161 * cond_resched() and cond_resched_lock(): latency reduction via
2162 * explicit rescheduling in places that are safe. The return
2163 * value indicates whether a reschedule was done in fact.
2164 * cond_resched_lock() will drop the spinlock before scheduling,
2165 * cond_resched_softirq() will enable bhs before scheduling.
2166 */
2167extern int _cond_resched(void);
2168#ifdef CONFIG_PREEMPT_BKL
2169static inline int cond_resched(void)
2170{
2171	return 0;
2172}
2173#else
2174static inline int cond_resched(void)
2175{
2176	return _cond_resched();
2177}
2178#endif
2179extern int cond_resched_lock(spinlock_t * lock);
2180extern int cond_resched_softirq(void);
2181static inline int cond_resched_bkl(void)
2182{
2183	return _cond_resched();
2184}
2185
2186/*
2187 * Does a critical section need to be broken due to another
2188 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2189 * but a general need for low latency)
2190 */
2191static inline int spin_needbreak(spinlock_t *lock)
2192{
2193#ifdef CONFIG_PREEMPT
2194	return spin_is_contended(lock);
2195#else
2196	return 0;
2197#endif
2198}
2199
2200/*
2201 * Thread group CPU time accounting.
2202 */
2203void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2204
2205static inline
2206void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times)
2207{
2208	struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
2209	unsigned long flags;
2210
2211	spin_lock_irqsave(&cputimer->lock, flags);
2212	*times = cputimer->cputime;
2213	spin_unlock_irqrestore(&cputimer->lock, flags);
2214}
2215
2216static inline void thread_group_cputime_init(struct signal_struct *sig)
2217{
2218	sig->cputimer.cputime = INIT_CPUTIME;
2219	spin_lock_init(&sig->cputimer.lock);
2220	sig->cputimer.running = 0;
2221}
2222
2223static inline void thread_group_cputime_free(struct signal_struct *sig)
2224{
2225}
2226
2227/*
2228 * Reevaluate whether the task has signals pending delivery.
2229 * Wake the task if so.
2230 * This is required every time the blocked sigset_t changes.
2231 * callers must hold sighand->siglock.
2232 */
2233extern void recalc_sigpending_and_wake(struct task_struct *t);
2234extern void recalc_sigpending(void);
2235
2236extern void signal_wake_up(struct task_struct *t, int resume_stopped);
2237
2238/*
2239 * Wrappers for p->thread_info->cpu access. No-op on UP.
2240 */
2241#ifdef CONFIG_SMP
2242
2243static inline unsigned int task_cpu(const struct task_struct *p)
2244{
2245	return task_thread_info(p)->cpu;
2246}
2247
2248extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2249
2250#else
2251
2252static inline unsigned int task_cpu(const struct task_struct *p)
2253{
2254	return 0;
2255}
2256
2257static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2258{
2259}
2260
2261#endif /* CONFIG_SMP */
2262
2263extern void arch_pick_mmap_layout(struct mm_struct *mm);
2264
2265#ifdef CONFIG_TRACING
2266extern void
2267__trace_special(void *__tr, void *__data,
2268		unsigned long arg1, unsigned long arg2, unsigned long arg3);
2269#else
2270static inline void
2271__trace_special(void *__tr, void *__data,
2272		unsigned long arg1, unsigned long arg2, unsigned long arg3)
2273{
2274}
2275#endif
2276
2277extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2278extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2279
2280extern void normalize_rt_tasks(void);
2281
2282#ifdef CONFIG_GROUP_SCHED
2283
2284extern struct task_group init_task_group;
2285#ifdef CONFIG_USER_SCHED
2286extern struct task_group root_task_group;
2287extern void set_tg_uid(struct user_struct *user);
2288#endif
2289
2290extern struct task_group *sched_create_group(struct task_group *parent);
2291extern void sched_destroy_group(struct task_group *tg);
2292extern void sched_move_task(struct task_struct *tsk);
2293#ifdef CONFIG_FAIR_GROUP_SCHED
2294extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2295extern unsigned long sched_group_shares(struct task_group *tg);
2296#endif
2297#ifdef CONFIG_RT_GROUP_SCHED
2298extern int sched_group_set_rt_runtime(struct task_group *tg,
2299				      long rt_runtime_us);
2300extern long sched_group_rt_runtime(struct task_group *tg);
2301extern int sched_group_set_rt_period(struct task_group *tg,
2302				      long rt_period_us);
2303extern long sched_group_rt_period(struct task_group *tg);
2304#endif
2305#endif
2306
2307#ifdef CONFIG_TASK_XACCT
2308static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2309{
2310	tsk->ioac.rchar += amt;
2311}
2312
2313static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2314{
2315	tsk->ioac.wchar += amt;
2316}
2317
2318static inline void inc_syscr(struct task_struct *tsk)
2319{
2320	tsk->ioac.syscr++;
2321}
2322
2323static inline void inc_syscw(struct task_struct *tsk)
2324{
2325	tsk->ioac.syscw++;
2326}
2327#else
2328static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2329{
2330}
2331
2332static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2333{
2334}
2335
2336static inline void inc_syscr(struct task_struct *tsk)
2337{
2338}
2339
2340static inline void inc_syscw(struct task_struct *tsk)
2341{
2342}
2343#endif
2344
2345#ifndef TASK_SIZE_OF
2346#define TASK_SIZE_OF(tsk)	TASK_SIZE
2347#endif
2348
2349#ifdef CONFIG_MM_OWNER
2350extern void mm_update_next_owner(struct mm_struct *mm);
2351extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2352#else
2353static inline void mm_update_next_owner(struct mm_struct *mm)
2354{
2355}
2356
2357static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2358{
2359}
2360#endif /* CONFIG_MM_OWNER */
2361
2362#define TASK_STATE_TO_CHAR_STR "RSDTtZX"
2363
2364#endif /* __KERNEL__ */
2365
2366#endif
2367