sched.h revision c714a534d85576af21b06be605ca55cb2fb887ee
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
91#include <asm/processor.h>
92
93struct mem_cgroup;
94struct exec_domain;
95struct futex_pi_state;
96struct robust_list_head;
97struct 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 */
115extern 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
129extern unsigned long total_forks;
130extern int nr_threads;
131DECLARE_PER_CPU(unsigned long, process_counts);
132extern int nr_processes(void);
133extern unsigned long nr_running(void);
134extern unsigned long nr_uninterruptible(void);
135extern unsigned long nr_active(void);
136extern unsigned long nr_iowait(void);
137extern unsigned long weighted_cpuload(const int cpu);
138
139struct seq_file;
140struct cfs_rq;
141struct task_group;
142#ifdef CONFIG_SCHED_DEBUG
143extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
144extern void proc_sched_set_task(struct task_struct *p);
145extern void
146print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
147#else
148static inline void
149proc_sched_show_task(struct task_struct *p, struct seq_file *m)
150{
151}
152static inline void proc_sched_set_task(struct task_struct *p)
153{
154}
155static inline void
156print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
157{
158}
159#endif
160
161extern unsigned long long time_sync_thresh;
162
163/*
164 * Task state bitmask. NOTE! These bits are also
165 * encoded in fs/proc/array.c: get_task_state().
166 *
167 * We have two separate sets of flags: task->state
168 * is about runnability, while task->exit_state are
169 * about the task exiting. Confusing, but this way
170 * modifying one set can't modify the other one by
171 * mistake.
172 */
173#define TASK_RUNNING		0
174#define TASK_INTERRUPTIBLE	1
175#define TASK_UNINTERRUPTIBLE	2
176#define __TASK_STOPPED		4
177#define __TASK_TRACED		8
178/* in tsk->exit_state */
179#define EXIT_ZOMBIE		16
180#define EXIT_DEAD		32
181/* in tsk->state again */
182#define TASK_DEAD		64
183#define TASK_WAKEKILL		128
184
185/* Convenience macros for the sake of set_task_state */
186#define TASK_KILLABLE		(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
187#define TASK_STOPPED		(TASK_WAKEKILL | __TASK_STOPPED)
188#define TASK_TRACED		(TASK_WAKEKILL | __TASK_TRACED)
189
190/* Convenience macros for the sake of wake_up */
191#define TASK_NORMAL		(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
192#define TASK_ALL		(TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
193
194/* get_task_state() */
195#define TASK_REPORT		(TASK_RUNNING | TASK_INTERRUPTIBLE | \
196				 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
197				 __TASK_TRACED)
198
199#define task_is_traced(task)	((task->state & __TASK_TRACED) != 0)
200#define task_is_stopped(task)	((task->state & __TASK_STOPPED) != 0)
201#define task_is_stopped_or_traced(task)	\
202			((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
203#define task_contributes_to_load(task)	\
204				((task->state & TASK_UNINTERRUPTIBLE) != 0)
205
206#define __set_task_state(tsk, state_value)		\
207	do { (tsk)->state = (state_value); } while (0)
208#define set_task_state(tsk, state_value)		\
209	set_mb((tsk)->state, (state_value))
210
211/*
212 * set_current_state() includes a barrier so that the write of current->state
213 * is correctly serialised wrt the caller's subsequent test of whether to
214 * actually sleep:
215 *
216 *	set_current_state(TASK_UNINTERRUPTIBLE);
217 *	if (do_i_need_to_sleep())
218 *		schedule();
219 *
220 * If the caller does not need such serialisation then use __set_current_state()
221 */
222#define __set_current_state(state_value)			\
223	do { current->state = (state_value); } while (0)
224#define set_current_state(state_value)		\
225	set_mb(current->state, (state_value))
226
227/* Task command name length */
228#define TASK_COMM_LEN 16
229
230#include <linux/spinlock.h>
231
232/*
233 * This serializes "schedule()" and also protects
234 * the run-queue from deletions/modifications (but
235 * _adding_ to the beginning of the run-queue has
236 * a separate lock).
237 */
238extern rwlock_t tasklist_lock;
239extern spinlock_t mmlist_lock;
240
241struct task_struct;
242
243extern void sched_init(void);
244extern void sched_init_smp(void);
245extern asmlinkage void schedule_tail(struct task_struct *prev);
246extern void init_idle(struct task_struct *idle, int cpu);
247extern void init_idle_bootup_task(struct task_struct *idle);
248
249extern cpumask_t nohz_cpu_mask;
250#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
251extern int select_nohz_load_balancer(int cpu);
252#else
253static inline int select_nohz_load_balancer(int cpu)
254{
255	return 0;
256}
257#endif
258
259extern unsigned long rt_needs_cpu(int cpu);
260
261/*
262 * Only dump TASK_* tasks. (0 for all tasks)
263 */
264extern void show_state_filter(unsigned long state_filter);
265
266static inline void show_state(void)
267{
268	show_state_filter(0);
269}
270
271extern void show_regs(struct pt_regs *);
272
273/*
274 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
275 * task), SP is the stack pointer of the first frame that should be shown in the back
276 * trace (or NULL if the entire call-chain of the task should be shown).
277 */
278extern void show_stack(struct task_struct *task, unsigned long *sp);
279
280void io_schedule(void);
281long io_schedule_timeout(long timeout);
282
283extern void cpu_init (void);
284extern void trap_init(void);
285extern void account_process_tick(struct task_struct *task, int user);
286extern void update_process_times(int user);
287extern void scheduler_tick(void);
288extern void hrtick_resched(void);
289
290extern void sched_show_task(struct task_struct *p);
291
292#ifdef CONFIG_DETECT_SOFTLOCKUP
293extern void softlockup_tick(void);
294extern void spawn_softlockup_task(void);
295extern void touch_softlockup_watchdog(void);
296extern void touch_all_softlockup_watchdogs(void);
297extern unsigned long  softlockup_thresh;
298extern unsigned long sysctl_hung_task_check_count;
299extern unsigned long sysctl_hung_task_timeout_secs;
300extern unsigned long sysctl_hung_task_warnings;
301#else
302static inline void softlockup_tick(void)
303{
304}
305static inline void spawn_softlockup_task(void)
306{
307}
308static inline void touch_softlockup_watchdog(void)
309{
310}
311static inline void touch_all_softlockup_watchdogs(void)
312{
313}
314#endif
315
316
317/* Attach to any functions which should be ignored in wchan output. */
318#define __sched		__attribute__((__section__(".sched.text")))
319
320/* Linker adds these: start and end of __sched functions */
321extern char __sched_text_start[], __sched_text_end[];
322
323/* Is this address in the __sched functions? */
324extern int in_sched_functions(unsigned long addr);
325
326#define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
327extern signed long schedule_timeout(signed long timeout);
328extern signed long schedule_timeout_interruptible(signed long timeout);
329extern signed long schedule_timeout_killable(signed long timeout);
330extern signed long schedule_timeout_uninterruptible(signed long timeout);
331asmlinkage void schedule(void);
332
333struct nsproxy;
334struct user_namespace;
335
336/* Maximum number of active map areas.. This is a random (large) number */
337#define DEFAULT_MAX_MAP_COUNT	65536
338
339extern int sysctl_max_map_count;
340
341#include <linux/aio.h>
342
343extern unsigned long
344arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
345		       unsigned long, unsigned long);
346extern unsigned long
347arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
348			  unsigned long len, unsigned long pgoff,
349			  unsigned long flags);
350extern void arch_unmap_area(struct mm_struct *, unsigned long);
351extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
352
353#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
354/*
355 * The mm counters are not protected by its page_table_lock,
356 * so must be incremented atomically.
357 */
358#define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
359#define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
360#define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
361#define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
362#define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
363
364#else  /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
365/*
366 * The mm counters are protected by its page_table_lock,
367 * so can be incremented directly.
368 */
369#define set_mm_counter(mm, member, value) (mm)->_##member = (value)
370#define get_mm_counter(mm, member) ((mm)->_##member)
371#define add_mm_counter(mm, member, value) (mm)->_##member += (value)
372#define inc_mm_counter(mm, member) (mm)->_##member++
373#define dec_mm_counter(mm, member) (mm)->_##member--
374
375#endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
376
377#define get_mm_rss(mm)					\
378	(get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
379#define update_hiwater_rss(mm)	do {			\
380	unsigned long _rss = get_mm_rss(mm);		\
381	if ((mm)->hiwater_rss < _rss)			\
382		(mm)->hiwater_rss = _rss;		\
383} while (0)
384#define update_hiwater_vm(mm)	do {			\
385	if ((mm)->hiwater_vm < (mm)->total_vm)		\
386		(mm)->hiwater_vm = (mm)->total_vm;	\
387} while (0)
388
389extern void set_dumpable(struct mm_struct *mm, int value);
390extern int get_dumpable(struct mm_struct *mm);
391
392/* mm flags */
393/* dumpable bits */
394#define MMF_DUMPABLE      0  /* core dump is permitted */
395#define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
396#define MMF_DUMPABLE_BITS 2
397
398/* coredump filter bits */
399#define MMF_DUMP_ANON_PRIVATE	2
400#define MMF_DUMP_ANON_SHARED	3
401#define MMF_DUMP_MAPPED_PRIVATE	4
402#define MMF_DUMP_MAPPED_SHARED	5
403#define MMF_DUMP_ELF_HEADERS	6
404#define MMF_DUMP_FILTER_SHIFT	MMF_DUMPABLE_BITS
405#define MMF_DUMP_FILTER_BITS	5
406#define MMF_DUMP_FILTER_MASK \
407	(((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
408#define MMF_DUMP_FILTER_DEFAULT \
409	((1 << MMF_DUMP_ANON_PRIVATE) |	(1 << MMF_DUMP_ANON_SHARED))
410
411struct sighand_struct {
412	atomic_t		count;
413	struct k_sigaction	action[_NSIG];
414	spinlock_t		siglock;
415	wait_queue_head_t	signalfd_wqh;
416};
417
418struct pacct_struct {
419	int			ac_flag;
420	long			ac_exitcode;
421	unsigned long		ac_mem;
422	cputime_t		ac_utime, ac_stime;
423	unsigned long		ac_minflt, ac_majflt;
424};
425
426/*
427 * NOTE! "signal_struct" does not have it's own
428 * locking, because a shared signal_struct always
429 * implies a shared sighand_struct, so locking
430 * sighand_struct is always a proper superset of
431 * the locking of signal_struct.
432 */
433struct signal_struct {
434	atomic_t		count;
435	atomic_t		live;
436
437	wait_queue_head_t	wait_chldexit;	/* for wait4() */
438
439	/* current thread group signal load-balancing target: */
440	struct task_struct	*curr_target;
441
442	/* shared signal handling: */
443	struct sigpending	shared_pending;
444
445	/* thread group exit support */
446	int			group_exit_code;
447	/* overloaded:
448	 * - notify group_exit_task when ->count is equal to notify_count
449	 * - everyone except group_exit_task is stopped during signal delivery
450	 *   of fatal signals, group_exit_task processes the signal.
451	 */
452	struct task_struct	*group_exit_task;
453	int			notify_count;
454
455	/* thread group stop support, overloads group_exit_code too */
456	int			group_stop_count;
457	unsigned int		flags; /* see SIGNAL_* flags below */
458
459	/* POSIX.1b Interval Timers */
460	struct list_head posix_timers;
461
462	/* ITIMER_REAL timer for the process */
463	struct hrtimer real_timer;
464	struct pid *leader_pid;
465	ktime_t it_real_incr;
466
467	/* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
468	cputime_t it_prof_expires, it_virt_expires;
469	cputime_t it_prof_incr, it_virt_incr;
470
471	/* job control IDs */
472
473	/*
474	 * pgrp and session fields are deprecated.
475	 * use the task_session_Xnr and task_pgrp_Xnr routines below
476	 */
477
478	union {
479		pid_t pgrp __deprecated;
480		pid_t __pgrp;
481	};
482
483	struct pid *tty_old_pgrp;
484
485	union {
486		pid_t session __deprecated;
487		pid_t __session;
488	};
489
490	/* boolean value for session group leader */
491	int leader;
492
493	struct tty_struct *tty; /* NULL if no tty */
494
495	/*
496	 * Cumulative resource counters for dead threads in the group,
497	 * and for reaped dead child processes forked by this group.
498	 * Live threads maintain their own counters and add to these
499	 * in __exit_signal, except for the group leader.
500	 */
501	cputime_t utime, stime, cutime, cstime;
502	cputime_t gtime;
503	cputime_t cgtime;
504	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
505	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
506	unsigned long inblock, oublock, cinblock, coublock;
507
508	/*
509	 * Cumulative ns of scheduled CPU time for dead threads in the
510	 * group, not including a zombie group leader.  (This only differs
511	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
512	 * other than jiffies.)
513	 */
514	unsigned long long sum_sched_runtime;
515
516	/*
517	 * We don't bother to synchronize most readers of this at all,
518	 * because there is no reader checking a limit that actually needs
519	 * to get both rlim_cur and rlim_max atomically, and either one
520	 * alone is a single word that can safely be read normally.
521	 * getrlimit/setrlimit use task_lock(current->group_leader) to
522	 * protect this instead of the siglock, because they really
523	 * have no need to disable irqs.
524	 */
525	struct rlimit rlim[RLIM_NLIMITS];
526
527	struct list_head cpu_timers[3];
528
529	/* keep the process-shared keyrings here so that they do the right
530	 * thing in threads created with CLONE_THREAD */
531#ifdef CONFIG_KEYS
532	struct key *session_keyring;	/* keyring inherited over fork */
533	struct key *process_keyring;	/* keyring private to this process */
534#endif
535#ifdef CONFIG_BSD_PROCESS_ACCT
536	struct pacct_struct pacct;	/* per-process accounting information */
537#endif
538#ifdef CONFIG_TASKSTATS
539	struct taskstats *stats;
540#endif
541#ifdef CONFIG_AUDIT
542	unsigned audit_tty;
543	struct tty_audit_buf *tty_audit_buf;
544#endif
545};
546
547/* Context switch must be unlocked if interrupts are to be enabled */
548#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
549# define __ARCH_WANT_UNLOCKED_CTXSW
550#endif
551
552/*
553 * Bits in flags field of signal_struct.
554 */
555#define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
556#define SIGNAL_STOP_DEQUEUED	0x00000002 /* stop signal dequeued */
557#define SIGNAL_STOP_CONTINUED	0x00000004 /* SIGCONT since WCONTINUED reap */
558#define SIGNAL_GROUP_EXIT	0x00000008 /* group exit in progress */
559/*
560 * Pending notifications to parent.
561 */
562#define SIGNAL_CLD_STOPPED	0x00000010
563#define SIGNAL_CLD_CONTINUED	0x00000020
564#define SIGNAL_CLD_MASK		(SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
565
566#define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */
567
568/* If true, all threads except ->group_exit_task have pending SIGKILL */
569static inline int signal_group_exit(const struct signal_struct *sig)
570{
571	return	(sig->flags & SIGNAL_GROUP_EXIT) ||
572		(sig->group_exit_task != NULL);
573}
574
575/*
576 * Some day this will be a full-fledged user tracking system..
577 */
578struct user_struct {
579	atomic_t __count;	/* reference count */
580	atomic_t processes;	/* How many processes does this user have? */
581	atomic_t files;		/* How many open files does this user have? */
582	atomic_t sigpending;	/* How many pending signals does this user have? */
583#ifdef CONFIG_INOTIFY_USER
584	atomic_t inotify_watches; /* How many inotify watches does this user have? */
585	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
586#endif
587#ifdef CONFIG_POSIX_MQUEUE
588	/* protected by mq_lock	*/
589	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
590#endif
591	unsigned long locked_shm; /* How many pages of mlocked shm ? */
592
593#ifdef CONFIG_KEYS
594	struct key *uid_keyring;	/* UID specific keyring */
595	struct key *session_keyring;	/* UID's default session keyring */
596#endif
597
598	/* Hash table maintenance information */
599	struct hlist_node uidhash_node;
600	uid_t uid;
601
602#ifdef CONFIG_USER_SCHED
603	struct task_group *tg;
604#ifdef CONFIG_SYSFS
605	struct kobject kobj;
606	struct work_struct work;
607#endif
608#endif
609};
610
611extern int uids_sysfs_init(void);
612
613extern struct user_struct *find_user(uid_t);
614
615extern struct user_struct root_user;
616#define INIT_USER (&root_user)
617
618struct backing_dev_info;
619struct reclaim_state;
620
621#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
622struct sched_info {
623	/* cumulative counters */
624	unsigned long pcount;	      /* # of times run on this cpu */
625	unsigned long long cpu_time,  /* time spent on the cpu */
626			   run_delay; /* time spent waiting on a runqueue */
627
628	/* timestamps */
629	unsigned long long last_arrival,/* when we last ran on a cpu */
630			   last_queued;	/* when we were last queued to run */
631#ifdef CONFIG_SCHEDSTATS
632	/* BKL stats */
633	unsigned int bkl_count;
634#endif
635};
636#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
637
638#ifdef CONFIG_SCHEDSTATS
639extern const struct file_operations proc_schedstat_operations;
640#endif /* CONFIG_SCHEDSTATS */
641
642#ifdef CONFIG_TASK_DELAY_ACCT
643struct task_delay_info {
644	spinlock_t	lock;
645	unsigned int	flags;	/* Private per-task flags */
646
647	/* For each stat XXX, add following, aligned appropriately
648	 *
649	 * struct timespec XXX_start, XXX_end;
650	 * u64 XXX_delay;
651	 * u32 XXX_count;
652	 *
653	 * Atomicity of updates to XXX_delay, XXX_count protected by
654	 * single lock above (split into XXX_lock if contention is an issue).
655	 */
656
657	/*
658	 * XXX_count is incremented on every XXX operation, the delay
659	 * associated with the operation is added to XXX_delay.
660	 * XXX_delay contains the accumulated delay time in nanoseconds.
661	 */
662	struct timespec blkio_start, blkio_end;	/* Shared by blkio, swapin */
663	u64 blkio_delay;	/* wait for sync block io completion */
664	u64 swapin_delay;	/* wait for swapin block io completion */
665	u32 blkio_count;	/* total count of the number of sync block */
666				/* io operations performed */
667	u32 swapin_count;	/* total count of the number of swapin block */
668				/* io operations performed */
669};
670#endif	/* CONFIG_TASK_DELAY_ACCT */
671
672static inline int sched_info_on(void)
673{
674#ifdef CONFIG_SCHEDSTATS
675	return 1;
676#elif defined(CONFIG_TASK_DELAY_ACCT)
677	extern int delayacct_on;
678	return delayacct_on;
679#else
680	return 0;
681#endif
682}
683
684enum cpu_idle_type {
685	CPU_IDLE,
686	CPU_NOT_IDLE,
687	CPU_NEWLY_IDLE,
688	CPU_MAX_IDLE_TYPES
689};
690
691/*
692 * sched-domains (multiprocessor balancing) declarations:
693 */
694
695/*
696 * Increase resolution of nice-level calculations:
697 */
698#define SCHED_LOAD_SHIFT	10
699#define SCHED_LOAD_SCALE	(1L << SCHED_LOAD_SHIFT)
700
701#define SCHED_LOAD_SCALE_FUZZ	SCHED_LOAD_SCALE
702
703#ifdef CONFIG_SMP
704#define SD_LOAD_BALANCE		1	/* Do load balancing on this domain. */
705#define SD_BALANCE_NEWIDLE	2	/* Balance when about to become idle */
706#define SD_BALANCE_EXEC		4	/* Balance on exec */
707#define SD_BALANCE_FORK		8	/* Balance on fork, clone */
708#define SD_WAKE_IDLE		16	/* Wake to idle CPU on task wakeup */
709#define SD_WAKE_AFFINE		32	/* Wake task to waking CPU */
710#define SD_WAKE_BALANCE		64	/* Perform balancing at task wakeup */
711#define SD_SHARE_CPUPOWER	128	/* Domain members share cpu power */
712#define SD_POWERSAVINGS_BALANCE	256	/* Balance for power savings */
713#define SD_SHARE_PKG_RESOURCES	512	/* Domain members share cpu pkg resources */
714#define SD_SERIALIZE		1024	/* Only a single load balancing instance */
715#define SD_WAKE_IDLE_FAR	2048	/* Gain latency sacrificing cache hit */
716
717#define BALANCE_FOR_MC_POWER	\
718	(sched_smt_power_savings ? SD_POWERSAVINGS_BALANCE : 0)
719
720#define BALANCE_FOR_PKG_POWER	\
721	((sched_mc_power_savings || sched_smt_power_savings) ?	\
722	 SD_POWERSAVINGS_BALANCE : 0)
723
724#define test_sd_parent(sd, flag)	((sd->parent &&		\
725					 (sd->parent->flags & flag)) ? 1 : 0)
726
727
728struct sched_group {
729	struct sched_group *next;	/* Must be a circular list */
730	cpumask_t cpumask;
731
732	/*
733	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
734	 * single CPU. This is read only (except for setup, hotplug CPU).
735	 * Note : Never change cpu_power without recompute its reciprocal
736	 */
737	unsigned int __cpu_power;
738	/*
739	 * reciprocal value of cpu_power to avoid expensive divides
740	 * (see include/linux/reciprocal_div.h)
741	 */
742	u32 reciprocal_cpu_power;
743};
744
745enum sched_domain_level {
746	SD_LV_NONE = 0,
747	SD_LV_SIBLING,
748	SD_LV_MC,
749	SD_LV_CPU,
750	SD_LV_NODE,
751	SD_LV_ALLNODES,
752	SD_LV_MAX
753};
754
755struct sched_domain_attr {
756	int relax_domain_level;
757};
758
759#define SD_ATTR_INIT	(struct sched_domain_attr) {	\
760	.relax_domain_level = -1,			\
761}
762
763struct sched_domain {
764	/* These fields must be setup */
765	struct sched_domain *parent;	/* top domain must be null terminated */
766	struct sched_domain *child;	/* bottom domain must be null terminated */
767	struct sched_group *groups;	/* the balancing groups of the domain */
768	cpumask_t span;			/* span of all CPUs in this domain */
769	int first_cpu;			/* cache of the first cpu in this domain */
770	unsigned long min_interval;	/* Minimum balance interval ms */
771	unsigned long max_interval;	/* Maximum balance interval ms */
772	unsigned int busy_factor;	/* less balancing by factor if busy */
773	unsigned int imbalance_pct;	/* No balance until over watermark */
774	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
775	unsigned int busy_idx;
776	unsigned int idle_idx;
777	unsigned int newidle_idx;
778	unsigned int wake_idx;
779	unsigned int forkexec_idx;
780	int flags;			/* See SD_* */
781	enum sched_domain_level level;
782
783	/* Runtime fields. */
784	unsigned long last_balance;	/* init to jiffies. units in jiffies */
785	unsigned int balance_interval;	/* initialise to 1. units in ms. */
786	unsigned int nr_balance_failed; /* initialise to 0 */
787
788#ifdef CONFIG_SCHEDSTATS
789	/* load_balance() stats */
790	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
791	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
792	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
793	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
794	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
795	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
796	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
797	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
798
799	/* Active load balancing */
800	unsigned int alb_count;
801	unsigned int alb_failed;
802	unsigned int alb_pushed;
803
804	/* SD_BALANCE_EXEC stats */
805	unsigned int sbe_count;
806	unsigned int sbe_balanced;
807	unsigned int sbe_pushed;
808
809	/* SD_BALANCE_FORK stats */
810	unsigned int sbf_count;
811	unsigned int sbf_balanced;
812	unsigned int sbf_pushed;
813
814	/* try_to_wake_up() stats */
815	unsigned int ttwu_wake_remote;
816	unsigned int ttwu_move_affine;
817	unsigned int ttwu_move_balance;
818#endif
819};
820
821extern void partition_sched_domains(int ndoms_new, cpumask_t *doms_new,
822				    struct sched_domain_attr *dattr_new);
823extern int arch_reinit_sched_domains(void);
824
825#endif	/* CONFIG_SMP */
826
827/*
828 * A runqueue laden with a single nice 0 task scores a weighted_cpuload of
829 * SCHED_LOAD_SCALE. This function returns 1 if any cpu is laden with a
830 * task of nice 0 or enough lower priority tasks to bring up the
831 * weighted_cpuload
832 */
833static inline int above_background_load(void)
834{
835	unsigned long cpu;
836
837	for_each_online_cpu(cpu) {
838		if (weighted_cpuload(cpu) >= SCHED_LOAD_SCALE)
839			return 1;
840	}
841	return 0;
842}
843
844struct io_context;			/* See blkdev.h */
845#define NGROUPS_SMALL		32
846#define NGROUPS_PER_BLOCK	((unsigned int)(PAGE_SIZE / sizeof(gid_t)))
847struct group_info {
848	int ngroups;
849	atomic_t usage;
850	gid_t small_block[NGROUPS_SMALL];
851	int nblocks;
852	gid_t *blocks[0];
853};
854
855/*
856 * get_group_info() must be called with the owning task locked (via task_lock())
857 * when task != current.  The reason being that the vast majority of callers are
858 * looking at current->group_info, which can not be changed except by the
859 * current task.  Changing current->group_info requires the task lock, too.
860 */
861#define get_group_info(group_info) do { \
862	atomic_inc(&(group_info)->usage); \
863} while (0)
864
865#define put_group_info(group_info) do { \
866	if (atomic_dec_and_test(&(group_info)->usage)) \
867		groups_free(group_info); \
868} while (0)
869
870extern struct group_info *groups_alloc(int gidsetsize);
871extern void groups_free(struct group_info *group_info);
872extern int set_current_groups(struct group_info *group_info);
873extern int groups_search(struct group_info *group_info, gid_t grp);
874/* access the groups "array" with this macro */
875#define GROUP_AT(gi, i) \
876    ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
877
878#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
879extern void prefetch_stack(struct task_struct *t);
880#else
881static inline void prefetch_stack(struct task_struct *t) { }
882#endif
883
884struct audit_context;		/* See audit.c */
885struct mempolicy;
886struct pipe_inode_info;
887struct uts_namespace;
888
889struct rq;
890struct sched_domain;
891
892struct sched_class {
893	const struct sched_class *next;
894
895	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int wakeup);
896	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int sleep);
897	void (*yield_task) (struct rq *rq);
898	int  (*select_task_rq)(struct task_struct *p, int sync);
899
900	void (*check_preempt_curr) (struct rq *rq, struct task_struct *p);
901
902	struct task_struct * (*pick_next_task) (struct rq *rq);
903	void (*put_prev_task) (struct rq *rq, struct task_struct *p);
904
905#ifdef CONFIG_SMP
906	unsigned long (*load_balance) (struct rq *this_rq, int this_cpu,
907			struct rq *busiest, unsigned long max_load_move,
908			struct sched_domain *sd, enum cpu_idle_type idle,
909			int *all_pinned, int *this_best_prio);
910
911	int (*move_one_task) (struct rq *this_rq, int this_cpu,
912			      struct rq *busiest, struct sched_domain *sd,
913			      enum cpu_idle_type idle);
914	void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
915	void (*post_schedule) (struct rq *this_rq);
916	void (*task_wake_up) (struct rq *this_rq, struct task_struct *task);
917#endif
918
919	void (*set_curr_task) (struct rq *rq);
920	void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
921	void (*task_new) (struct rq *rq, struct task_struct *p);
922	void (*set_cpus_allowed)(struct task_struct *p,
923				 const cpumask_t *newmask);
924
925	void (*join_domain)(struct rq *rq);
926	void (*leave_domain)(struct rq *rq);
927
928	void (*switched_from) (struct rq *this_rq, struct task_struct *task,
929			       int running);
930	void (*switched_to) (struct rq *this_rq, struct task_struct *task,
931			     int running);
932	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
933			     int oldprio, int running);
934
935#ifdef CONFIG_FAIR_GROUP_SCHED
936	void (*moved_group) (struct task_struct *p);
937#endif
938};
939
940struct load_weight {
941	unsigned long weight, inv_weight;
942};
943
944/*
945 * CFS stats for a schedulable entity (task, task-group etc)
946 *
947 * Current field usage histogram:
948 *
949 *     4 se->block_start
950 *     4 se->run_node
951 *     4 se->sleep_start
952 *     6 se->load.weight
953 */
954struct sched_entity {
955	struct load_weight	load;		/* for load-balancing */
956	struct rb_node		run_node;
957	struct list_head	group_node;
958	unsigned int		on_rq;
959
960	u64			exec_start;
961	u64			sum_exec_runtime;
962	u64			vruntime;
963	u64			prev_sum_exec_runtime;
964
965	u64			last_wakeup;
966	u64			avg_overlap;
967
968#ifdef CONFIG_SCHEDSTATS
969	u64			wait_start;
970	u64			wait_max;
971	u64			wait_count;
972	u64			wait_sum;
973
974	u64			sleep_start;
975	u64			sleep_max;
976	s64			sum_sleep_runtime;
977
978	u64			block_start;
979	u64			block_max;
980	u64			exec_max;
981	u64			slice_max;
982
983	u64			nr_migrations;
984	u64			nr_migrations_cold;
985	u64			nr_failed_migrations_affine;
986	u64			nr_failed_migrations_running;
987	u64			nr_failed_migrations_hot;
988	u64			nr_forced_migrations;
989	u64			nr_forced2_migrations;
990
991	u64			nr_wakeups;
992	u64			nr_wakeups_sync;
993	u64			nr_wakeups_migrate;
994	u64			nr_wakeups_local;
995	u64			nr_wakeups_remote;
996	u64			nr_wakeups_affine;
997	u64			nr_wakeups_affine_attempts;
998	u64			nr_wakeups_passive;
999	u64			nr_wakeups_idle;
1000#endif
1001
1002#ifdef CONFIG_FAIR_GROUP_SCHED
1003	struct sched_entity	*parent;
1004	/* rq on which this entity is (to be) queued: */
1005	struct cfs_rq		*cfs_rq;
1006	/* rq "owned" by this entity/group: */
1007	struct cfs_rq		*my_q;
1008#endif
1009};
1010
1011struct sched_rt_entity {
1012	struct list_head run_list;
1013	unsigned int time_slice;
1014	unsigned long timeout;
1015	int nr_cpus_allowed;
1016
1017	struct sched_rt_entity *back;
1018#ifdef CONFIG_RT_GROUP_SCHED
1019	struct sched_rt_entity	*parent;
1020	/* rq on which this entity is (to be) queued: */
1021	struct rt_rq		*rt_rq;
1022	/* rq "owned" by this entity/group: */
1023	struct rt_rq		*my_q;
1024#endif
1025};
1026
1027struct task_struct {
1028	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
1029	void *stack;
1030	atomic_t usage;
1031	unsigned int flags;	/* per process flags, defined below */
1032	unsigned int ptrace;
1033
1034	int lock_depth;		/* BKL lock depth */
1035
1036#ifdef CONFIG_SMP
1037#ifdef __ARCH_WANT_UNLOCKED_CTXSW
1038	int oncpu;
1039#endif
1040#endif
1041
1042	int prio, static_prio, normal_prio;
1043	const struct sched_class *sched_class;
1044	struct sched_entity se;
1045	struct sched_rt_entity rt;
1046
1047#ifdef CONFIG_PREEMPT_NOTIFIERS
1048	/* list of struct preempt_notifier: */
1049	struct hlist_head preempt_notifiers;
1050#endif
1051
1052	/*
1053	 * fpu_counter contains the number of consecutive context switches
1054	 * that the FPU is used. If this is over a threshold, the lazy fpu
1055	 * saving becomes unlazy to save the trap. This is an unsigned char
1056	 * so that after 256 times the counter wraps and the behavior turns
1057	 * lazy again; this to deal with bursty apps that only use FPU for
1058	 * a short time
1059	 */
1060	unsigned char fpu_counter;
1061	s8 oomkilladj; /* OOM kill score adjustment (bit shift). */
1062#ifdef CONFIG_BLK_DEV_IO_TRACE
1063	unsigned int btrace_seq;
1064#endif
1065
1066	unsigned int policy;
1067	cpumask_t cpus_allowed;
1068
1069#ifdef CONFIG_PREEMPT_RCU
1070	int rcu_read_lock_nesting;
1071	int rcu_flipctr_idx;
1072#endif /* #ifdef CONFIG_PREEMPT_RCU */
1073
1074#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1075	struct sched_info sched_info;
1076#endif
1077
1078	struct list_head tasks;
1079	/*
1080	 * ptrace_list/ptrace_children forms the list of my children
1081	 * that were stolen by a ptracer.
1082	 */
1083	struct list_head ptrace_children;
1084	struct list_head ptrace_list;
1085
1086	struct mm_struct *mm, *active_mm;
1087
1088/* task state */
1089	struct linux_binfmt *binfmt;
1090	int exit_state;
1091	int exit_code, exit_signal;
1092	int pdeath_signal;  /*  The signal sent when the parent dies  */
1093	/* ??? */
1094	unsigned int personality;
1095	unsigned did_exec:1;
1096	pid_t pid;
1097	pid_t tgid;
1098
1099#ifdef CONFIG_CC_STACKPROTECTOR
1100	/* Canary value for the -fstack-protector gcc feature */
1101	unsigned long stack_canary;
1102#endif
1103	/*
1104	 * pointers to (original) parent process, youngest child, younger sibling,
1105	 * older sibling, respectively.  (p->father can be replaced with
1106	 * p->parent->pid)
1107	 */
1108	struct task_struct *real_parent; /* real parent process (when being debugged) */
1109	struct task_struct *parent;	/* parent process */
1110	/*
1111	 * children/sibling forms the list of my children plus the
1112	 * tasks I'm ptracing.
1113	 */
1114	struct list_head children;	/* list of my children */
1115	struct list_head sibling;	/* linkage in my parent's children list */
1116	struct task_struct *group_leader;	/* threadgroup leader */
1117
1118	/* PID/PID hash table linkage. */
1119	struct pid_link pids[PIDTYPE_MAX];
1120	struct list_head thread_group;
1121
1122	struct completion *vfork_done;		/* for vfork() */
1123	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
1124	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
1125
1126	unsigned int rt_priority;
1127	cputime_t utime, stime, utimescaled, stimescaled;
1128	cputime_t gtime;
1129	cputime_t prev_utime, prev_stime;
1130	unsigned long nvcsw, nivcsw; /* context switch counts */
1131	struct timespec start_time; 		/* monotonic time */
1132	struct timespec real_start_time;	/* boot based time */
1133/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1134	unsigned long min_flt, maj_flt;
1135
1136  	cputime_t it_prof_expires, it_virt_expires;
1137	unsigned long long it_sched_expires;
1138	struct list_head cpu_timers[3];
1139
1140/* process credentials */
1141	uid_t uid,euid,suid,fsuid;
1142	gid_t gid,egid,sgid,fsgid;
1143	struct group_info *group_info;
1144	kernel_cap_t   cap_effective, cap_inheritable, cap_permitted, cap_bset;
1145	unsigned securebits;
1146	struct user_struct *user;
1147#ifdef CONFIG_KEYS
1148	struct key *request_key_auth;	/* assumed request_key authority */
1149	struct key *thread_keyring;	/* keyring private to this thread */
1150	unsigned char jit_keyring;	/* default keyring to attach requested keys to */
1151#endif
1152	char comm[TASK_COMM_LEN]; /* executable name excluding path
1153				     - access with [gs]et_task_comm (which lock
1154				       it with task_lock())
1155				     - initialized normally by flush_old_exec */
1156/* file system info */
1157	int link_count, total_link_count;
1158#ifdef CONFIG_SYSVIPC
1159/* ipc stuff */
1160	struct sysv_sem sysvsem;
1161#endif
1162#ifdef CONFIG_DETECT_SOFTLOCKUP
1163/* hung task detection */
1164	unsigned long last_switch_timestamp;
1165	unsigned long last_switch_count;
1166#endif
1167/* CPU-specific state of this task */
1168	struct thread_struct thread;
1169/* filesystem information */
1170	struct fs_struct *fs;
1171/* open file information */
1172	struct files_struct *files;
1173/* namespaces */
1174	struct nsproxy *nsproxy;
1175/* signal handlers */
1176	struct signal_struct *signal;
1177	struct sighand_struct *sighand;
1178
1179	sigset_t blocked, real_blocked;
1180	sigset_t saved_sigmask;	/* restored if set_restore_sigmask() was used */
1181	struct sigpending pending;
1182
1183	unsigned long sas_ss_sp;
1184	size_t sas_ss_size;
1185	int (*notifier)(void *priv);
1186	void *notifier_data;
1187	sigset_t *notifier_mask;
1188#ifdef CONFIG_SECURITY
1189	void *security;
1190#endif
1191	struct audit_context *audit_context;
1192#ifdef CONFIG_AUDITSYSCALL
1193	uid_t loginuid;
1194	unsigned int sessionid;
1195#endif
1196	seccomp_t seccomp;
1197
1198/* Thread group tracking */
1199   	u32 parent_exec_id;
1200   	u32 self_exec_id;
1201/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
1202	spinlock_t alloc_lock;
1203
1204	/* Protection of the PI data structures: */
1205	spinlock_t pi_lock;
1206
1207#ifdef CONFIG_RT_MUTEXES
1208	/* PI waiters blocked on a rt_mutex held by this task */
1209	struct plist_head pi_waiters;
1210	/* Deadlock detection and priority inheritance handling */
1211	struct rt_mutex_waiter *pi_blocked_on;
1212#endif
1213
1214#ifdef CONFIG_DEBUG_MUTEXES
1215	/* mutex deadlock detection */
1216	struct mutex_waiter *blocked_on;
1217#endif
1218#ifdef CONFIG_TRACE_IRQFLAGS
1219	unsigned int irq_events;
1220	int hardirqs_enabled;
1221	unsigned long hardirq_enable_ip;
1222	unsigned int hardirq_enable_event;
1223	unsigned long hardirq_disable_ip;
1224	unsigned int hardirq_disable_event;
1225	int softirqs_enabled;
1226	unsigned long softirq_disable_ip;
1227	unsigned int softirq_disable_event;
1228	unsigned long softirq_enable_ip;
1229	unsigned int softirq_enable_event;
1230	int hardirq_context;
1231	int softirq_context;
1232#endif
1233#ifdef CONFIG_LOCKDEP
1234# define MAX_LOCK_DEPTH 48UL
1235	u64 curr_chain_key;
1236	int lockdep_depth;
1237	struct held_lock held_locks[MAX_LOCK_DEPTH];
1238	unsigned int lockdep_recursion;
1239#endif
1240
1241/* journalling filesystem info */
1242	void *journal_info;
1243
1244/* stacked block device info */
1245	struct bio *bio_list, **bio_tail;
1246
1247/* VM state */
1248	struct reclaim_state *reclaim_state;
1249
1250	struct backing_dev_info *backing_dev_info;
1251
1252	struct io_context *io_context;
1253
1254	unsigned long ptrace_message;
1255	siginfo_t *last_siginfo; /* For ptrace use.  */
1256#ifdef CONFIG_TASK_XACCT
1257/* i/o counters(bytes read/written, #syscalls */
1258	u64 rchar, wchar, syscr, syscw;
1259#endif
1260	struct task_io_accounting ioac;
1261#if defined(CONFIG_TASK_XACCT)
1262	u64 acct_rss_mem1;	/* accumulated rss usage */
1263	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1264	cputime_t acct_stimexpd;/* stime since last update */
1265#endif
1266#ifdef CONFIG_NUMA
1267  	struct mempolicy *mempolicy;
1268	short il_next;
1269#endif
1270#ifdef CONFIG_CPUSETS
1271	nodemask_t mems_allowed;
1272	int cpuset_mems_generation;
1273	int cpuset_mem_spread_rotor;
1274#endif
1275#ifdef CONFIG_CGROUPS
1276	/* Control Group info protected by css_set_lock */
1277	struct css_set *cgroups;
1278	/* cg_list protected by css_set_lock and tsk->alloc_lock */
1279	struct list_head cg_list;
1280#endif
1281#ifdef CONFIG_FUTEX
1282	struct robust_list_head __user *robust_list;
1283#ifdef CONFIG_COMPAT
1284	struct compat_robust_list_head __user *compat_robust_list;
1285#endif
1286	struct list_head pi_state_list;
1287	struct futex_pi_state *pi_state_cache;
1288#endif
1289	atomic_t fs_excl;	/* holding fs exclusive resources */
1290	struct rcu_head rcu;
1291
1292	/*
1293	 * cache last used pipe for splice
1294	 */
1295	struct pipe_inode_info *splice_pipe;
1296#ifdef	CONFIG_TASK_DELAY_ACCT
1297	struct task_delay_info *delays;
1298#endif
1299#ifdef CONFIG_FAULT_INJECTION
1300	int make_it_fail;
1301#endif
1302	struct prop_local_single dirties;
1303#ifdef CONFIG_LATENCYTOP
1304	int latency_record_count;
1305	struct latency_record latency_record[LT_SAVECOUNT];
1306#endif
1307};
1308
1309/*
1310 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1311 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1312 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1313 * values are inverted: lower p->prio value means higher priority.
1314 *
1315 * The MAX_USER_RT_PRIO value allows the actual maximum
1316 * RT priority to be separate from the value exported to
1317 * user-space.  This allows kernel threads to set their
1318 * priority to a value higher than any user task. Note:
1319 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1320 */
1321
1322#define MAX_USER_RT_PRIO	100
1323#define MAX_RT_PRIO		MAX_USER_RT_PRIO
1324
1325#define MAX_PRIO		(MAX_RT_PRIO + 40)
1326#define DEFAULT_PRIO		(MAX_RT_PRIO + 20)
1327
1328static inline int rt_prio(int prio)
1329{
1330	if (unlikely(prio < MAX_RT_PRIO))
1331		return 1;
1332	return 0;
1333}
1334
1335static inline int rt_task(struct task_struct *p)
1336{
1337	return rt_prio(p->prio);
1338}
1339
1340static inline void set_task_session(struct task_struct *tsk, pid_t session)
1341{
1342	tsk->signal->__session = session;
1343}
1344
1345static inline void set_task_pgrp(struct task_struct *tsk, pid_t pgrp)
1346{
1347	tsk->signal->__pgrp = pgrp;
1348}
1349
1350static inline struct pid *task_pid(struct task_struct *task)
1351{
1352	return task->pids[PIDTYPE_PID].pid;
1353}
1354
1355static inline struct pid *task_tgid(struct task_struct *task)
1356{
1357	return task->group_leader->pids[PIDTYPE_PID].pid;
1358}
1359
1360static inline struct pid *task_pgrp(struct task_struct *task)
1361{
1362	return task->group_leader->pids[PIDTYPE_PGID].pid;
1363}
1364
1365static inline struct pid *task_session(struct task_struct *task)
1366{
1367	return task->group_leader->pids[PIDTYPE_SID].pid;
1368}
1369
1370struct pid_namespace;
1371
1372/*
1373 * the helpers to get the task's different pids as they are seen
1374 * from various namespaces
1375 *
1376 * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1377 * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1378 *                     current.
1379 * task_xid_nr_ns()  : id seen from the ns specified;
1380 *
1381 * set_task_vxid()   : assigns a virtual id to a task;
1382 *
1383 * see also pid_nr() etc in include/linux/pid.h
1384 */
1385
1386static inline pid_t task_pid_nr(struct task_struct *tsk)
1387{
1388	return tsk->pid;
1389}
1390
1391pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1392
1393static inline pid_t task_pid_vnr(struct task_struct *tsk)
1394{
1395	return pid_vnr(task_pid(tsk));
1396}
1397
1398
1399static inline pid_t task_tgid_nr(struct task_struct *tsk)
1400{
1401	return tsk->tgid;
1402}
1403
1404pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1405
1406static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1407{
1408	return pid_vnr(task_tgid(tsk));
1409}
1410
1411
1412static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1413{
1414	return tsk->signal->__pgrp;
1415}
1416
1417pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1418
1419static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1420{
1421	return pid_vnr(task_pgrp(tsk));
1422}
1423
1424
1425static inline pid_t task_session_nr(struct task_struct *tsk)
1426{
1427	return tsk->signal->__session;
1428}
1429
1430pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1431
1432static inline pid_t task_session_vnr(struct task_struct *tsk)
1433{
1434	return pid_vnr(task_session(tsk));
1435}
1436
1437
1438/**
1439 * pid_alive - check that a task structure is not stale
1440 * @p: Task structure to be checked.
1441 *
1442 * Test if a process is not yet dead (at most zombie state)
1443 * If pid_alive fails, then pointers within the task structure
1444 * can be stale and must not be dereferenced.
1445 */
1446static inline int pid_alive(struct task_struct *p)
1447{
1448	return p->pids[PIDTYPE_PID].pid != NULL;
1449}
1450
1451/**
1452 * is_global_init - check if a task structure is init
1453 * @tsk: Task structure to be checked.
1454 *
1455 * Check if a task structure is the first user space task the kernel created.
1456 */
1457static inline int is_global_init(struct task_struct *tsk)
1458{
1459	return tsk->pid == 1;
1460}
1461
1462/*
1463 * is_container_init:
1464 * check whether in the task is init in its own pid namespace.
1465 */
1466extern int is_container_init(struct task_struct *tsk);
1467
1468extern struct pid *cad_pid;
1469
1470extern void free_task(struct task_struct *tsk);
1471#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1472
1473extern void __put_task_struct(struct task_struct *t);
1474
1475static inline void put_task_struct(struct task_struct *t)
1476{
1477	if (atomic_dec_and_test(&t->usage))
1478		__put_task_struct(t);
1479}
1480
1481/*
1482 * Per process flags
1483 */
1484#define PF_ALIGNWARN	0x00000001	/* Print alignment warning msgs */
1485					/* Not implemented yet, only for 486*/
1486#define PF_STARTING	0x00000002	/* being created */
1487#define PF_EXITING	0x00000004	/* getting shut down */
1488#define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
1489#define PF_VCPU		0x00000010	/* I'm a virtual CPU */
1490#define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
1491#define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
1492#define PF_DUMPCORE	0x00000200	/* dumped core */
1493#define PF_SIGNALED	0x00000400	/* killed by a signal */
1494#define PF_MEMALLOC	0x00000800	/* Allocating memory */
1495#define PF_FLUSHER	0x00001000	/* responsible for disk writeback */
1496#define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
1497#define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
1498#define PF_FROZEN	0x00010000	/* frozen for system suspend */
1499#define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
1500#define PF_KSWAPD	0x00040000	/* I am kswapd */
1501#define PF_SWAPOFF	0x00080000	/* I am in swapoff */
1502#define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
1503#define PF_BORROWED_MM	0x00200000	/* I am a kthread doing use_mm */
1504#define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
1505#define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
1506#define PF_SPREAD_PAGE	0x01000000	/* Spread page cache over cpuset */
1507#define PF_SPREAD_SLAB	0x02000000	/* Spread some slab caches over cpuset */
1508#define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
1509#define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
1510#define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezeable */
1511
1512/*
1513 * Only the _current_ task can read/write to tsk->flags, but other
1514 * tasks can access tsk->flags in readonly mode for example
1515 * with tsk_used_math (like during threaded core dumping).
1516 * There is however an exception to this rule during ptrace
1517 * or during fork: the ptracer task is allowed to write to the
1518 * child->flags of its traced child (same goes for fork, the parent
1519 * can write to the child->flags), because we're guaranteed the
1520 * child is not running and in turn not changing child->flags
1521 * at the same time the parent does it.
1522 */
1523#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1524#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1525#define clear_used_math() clear_stopped_child_used_math(current)
1526#define set_used_math() set_stopped_child_used_math(current)
1527#define conditional_stopped_child_used_math(condition, child) \
1528	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1529#define conditional_used_math(condition) \
1530	conditional_stopped_child_used_math(condition, current)
1531#define copy_to_stopped_child_used_math(child) \
1532	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1533/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1534#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1535#define used_math() tsk_used_math(current)
1536
1537#ifdef CONFIG_SMP
1538extern int set_cpus_allowed_ptr(struct task_struct *p,
1539				const cpumask_t *new_mask);
1540#else
1541static inline int set_cpus_allowed_ptr(struct task_struct *p,
1542				       const cpumask_t *new_mask)
1543{
1544	if (!cpu_isset(0, *new_mask))
1545		return -EINVAL;
1546	return 0;
1547}
1548#endif
1549static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1550{
1551	return set_cpus_allowed_ptr(p, &new_mask);
1552}
1553
1554extern unsigned long long sched_clock(void);
1555
1556#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1557static inline void sched_clock_init(void)
1558{
1559}
1560
1561static inline u64 sched_clock_cpu(int cpu)
1562{
1563	return sched_clock();
1564}
1565
1566static inline void sched_clock_tick(void)
1567{
1568}
1569
1570static inline void sched_clock_idle_sleep_event(void)
1571{
1572}
1573
1574static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
1575{
1576}
1577#else
1578extern void sched_clock_init(void);
1579extern u64 sched_clock_cpu(int cpu);
1580extern void sched_clock_tick(void);
1581extern void sched_clock_idle_sleep_event(void);
1582extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1583#endif
1584
1585/*
1586 * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
1587 * clock constructed from sched_clock():
1588 */
1589extern unsigned long long cpu_clock(int cpu);
1590
1591extern unsigned long long
1592task_sched_runtime(struct task_struct *task);
1593
1594/* sched_exec is called by processes performing an exec */
1595#ifdef CONFIG_SMP
1596extern void sched_exec(void);
1597#else
1598#define sched_exec()   {}
1599#endif
1600
1601extern void sched_clock_idle_sleep_event(void);
1602extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1603
1604#ifdef CONFIG_HOTPLUG_CPU
1605extern void idle_task_exit(void);
1606#else
1607static inline void idle_task_exit(void) {}
1608#endif
1609
1610extern void sched_idle_next(void);
1611
1612#if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
1613extern void wake_up_idle_cpu(int cpu);
1614#else
1615static inline void wake_up_idle_cpu(int cpu) { }
1616#endif
1617
1618#ifdef CONFIG_SCHED_DEBUG
1619extern unsigned int sysctl_sched_latency;
1620extern unsigned int sysctl_sched_min_granularity;
1621extern unsigned int sysctl_sched_wakeup_granularity;
1622extern unsigned int sysctl_sched_child_runs_first;
1623extern unsigned int sysctl_sched_features;
1624extern unsigned int sysctl_sched_migration_cost;
1625extern unsigned int sysctl_sched_nr_migrate;
1626
1627int sched_nr_latency_handler(struct ctl_table *table, int write,
1628		struct file *file, void __user *buffer, size_t *length,
1629		loff_t *ppos);
1630#endif
1631extern unsigned int sysctl_sched_rt_period;
1632extern int sysctl_sched_rt_runtime;
1633
1634int sched_rt_handler(struct ctl_table *table, int write,
1635		struct file *filp, void __user *buffer, size_t *lenp,
1636		loff_t *ppos);
1637
1638extern unsigned int sysctl_sched_compat_yield;
1639
1640#ifdef CONFIG_RT_MUTEXES
1641extern int rt_mutex_getprio(struct task_struct *p);
1642extern void rt_mutex_setprio(struct task_struct *p, int prio);
1643extern void rt_mutex_adjust_pi(struct task_struct *p);
1644#else
1645static inline int rt_mutex_getprio(struct task_struct *p)
1646{
1647	return p->normal_prio;
1648}
1649# define rt_mutex_adjust_pi(p)		do { } while (0)
1650#endif
1651
1652extern void set_user_nice(struct task_struct *p, long nice);
1653extern int task_prio(const struct task_struct *p);
1654extern int task_nice(const struct task_struct *p);
1655extern int can_nice(const struct task_struct *p, const int nice);
1656extern int task_curr(const struct task_struct *p);
1657extern int idle_cpu(int cpu);
1658extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1659extern struct task_struct *idle_task(int cpu);
1660extern struct task_struct *curr_task(int cpu);
1661extern void set_curr_task(int cpu, struct task_struct *p);
1662
1663void yield(void);
1664
1665/*
1666 * The default (Linux) execution domain.
1667 */
1668extern struct exec_domain	default_exec_domain;
1669
1670union thread_union {
1671	struct thread_info thread_info;
1672	unsigned long stack[THREAD_SIZE/sizeof(long)];
1673};
1674
1675#ifndef __HAVE_ARCH_KSTACK_END
1676static inline int kstack_end(void *addr)
1677{
1678	/* Reliable end of stack detection:
1679	 * Some APM bios versions misalign the stack
1680	 */
1681	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1682}
1683#endif
1684
1685extern union thread_union init_thread_union;
1686extern struct task_struct init_task;
1687
1688extern struct   mm_struct init_mm;
1689
1690extern struct pid_namespace init_pid_ns;
1691
1692/*
1693 * find a task by one of its numerical ids
1694 *
1695 * find_task_by_pid_type_ns():
1696 *      it is the most generic call - it finds a task by all id,
1697 *      type and namespace specified
1698 * find_task_by_pid_ns():
1699 *      finds a task by its pid in the specified namespace
1700 * find_task_by_vpid():
1701 *      finds a task by its virtual pid
1702 * find_task_by_pid():
1703 *      finds a task by its global pid
1704 *
1705 * see also find_pid() etc in include/linux/pid.h
1706 */
1707
1708extern struct task_struct *find_task_by_pid_type_ns(int type, int pid,
1709		struct pid_namespace *ns);
1710
1711static inline struct task_struct *__deprecated find_task_by_pid(pid_t nr)
1712{
1713	return find_task_by_pid_type_ns(PIDTYPE_PID, nr, &init_pid_ns);
1714}
1715extern struct task_struct *find_task_by_vpid(pid_t nr);
1716extern struct task_struct *find_task_by_pid_ns(pid_t nr,
1717		struct pid_namespace *ns);
1718
1719extern void __set_special_pids(struct pid *pid);
1720
1721/* per-UID process charging. */
1722extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
1723static inline struct user_struct *get_uid(struct user_struct *u)
1724{
1725	atomic_inc(&u->__count);
1726	return u;
1727}
1728extern void free_uid(struct user_struct *);
1729extern void switch_uid(struct user_struct *);
1730extern void release_uids(struct user_namespace *ns);
1731
1732#include <asm/current.h>
1733
1734extern void do_timer(unsigned long ticks);
1735
1736extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1737extern int wake_up_process(struct task_struct *tsk);
1738extern void wake_up_new_task(struct task_struct *tsk,
1739				unsigned long clone_flags);
1740#ifdef CONFIG_SMP
1741 extern void kick_process(struct task_struct *tsk);
1742#else
1743 static inline void kick_process(struct task_struct *tsk) { }
1744#endif
1745extern void sched_fork(struct task_struct *p, int clone_flags);
1746extern void sched_dead(struct task_struct *p);
1747
1748extern int in_group_p(gid_t);
1749extern int in_egroup_p(gid_t);
1750
1751extern void proc_caches_init(void);
1752extern void flush_signals(struct task_struct *);
1753extern void ignore_signals(struct task_struct *);
1754extern void flush_signal_handlers(struct task_struct *, int force_default);
1755extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1756
1757static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1758{
1759	unsigned long flags;
1760	int ret;
1761
1762	spin_lock_irqsave(&tsk->sighand->siglock, flags);
1763	ret = dequeue_signal(tsk, mask, info);
1764	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1765
1766	return ret;
1767}
1768
1769extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1770			      sigset_t *mask);
1771extern void unblock_all_signals(void);
1772extern void release_task(struct task_struct * p);
1773extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1774extern int force_sigsegv(int, struct task_struct *);
1775extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1776extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1777extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
1778extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
1779extern int kill_pgrp(struct pid *pid, int sig, int priv);
1780extern int kill_pid(struct pid *pid, int sig, int priv);
1781extern int kill_proc_info(int, struct siginfo *, pid_t);
1782extern void do_notify_parent(struct task_struct *, int);
1783extern void force_sig(int, struct task_struct *);
1784extern void force_sig_specific(int, struct task_struct *);
1785extern int send_sig(int, struct task_struct *, int);
1786extern void zap_other_threads(struct task_struct *p);
1787extern int kill_proc(pid_t, int, int);
1788extern struct sigqueue *sigqueue_alloc(void);
1789extern void sigqueue_free(struct sigqueue *);
1790extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
1791extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
1792extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1793
1794static inline int kill_cad_pid(int sig, int priv)
1795{
1796	return kill_pid(cad_pid, sig, priv);
1797}
1798
1799/* These can be the second arg to send_sig_info/send_group_sig_info.  */
1800#define SEND_SIG_NOINFO ((struct siginfo *) 0)
1801#define SEND_SIG_PRIV	((struct siginfo *) 1)
1802#define SEND_SIG_FORCED	((struct siginfo *) 2)
1803
1804static inline int is_si_special(const struct siginfo *info)
1805{
1806	return info <= SEND_SIG_FORCED;
1807}
1808
1809/* True if we are on the alternate signal stack.  */
1810
1811static inline int on_sig_stack(unsigned long sp)
1812{
1813	return (sp - current->sas_ss_sp < current->sas_ss_size);
1814}
1815
1816static inline int sas_ss_flags(unsigned long sp)
1817{
1818	return (current->sas_ss_size == 0 ? SS_DISABLE
1819		: on_sig_stack(sp) ? SS_ONSTACK : 0);
1820}
1821
1822/*
1823 * Routines for handling mm_structs
1824 */
1825extern struct mm_struct * mm_alloc(void);
1826
1827/* mmdrop drops the mm and the page tables */
1828extern void __mmdrop(struct mm_struct *);
1829static inline void mmdrop(struct mm_struct * mm)
1830{
1831	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
1832		__mmdrop(mm);
1833}
1834
1835/* mmput gets rid of the mappings and all user-space */
1836extern void mmput(struct mm_struct *);
1837/* Grab a reference to a task's mm, if it is not already going away */
1838extern struct mm_struct *get_task_mm(struct task_struct *task);
1839/* Remove the current tasks stale references to the old mm_struct */
1840extern void mm_release(struct task_struct *, struct mm_struct *);
1841/* Allocate a new mm structure and copy contents from tsk->mm */
1842extern struct mm_struct *dup_mm(struct task_struct *tsk);
1843
1844extern int  copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1845extern void flush_thread(void);
1846extern void exit_thread(void);
1847
1848extern void exit_files(struct task_struct *);
1849extern void __cleanup_signal(struct signal_struct *);
1850extern void __cleanup_sighand(struct sighand_struct *);
1851extern void exit_itimers(struct signal_struct *);
1852
1853extern NORET_TYPE void do_group_exit(int);
1854
1855extern void daemonize(const char *, ...);
1856extern int allow_signal(int);
1857extern int disallow_signal(int);
1858
1859extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1860extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1861struct task_struct *fork_idle(int);
1862
1863extern void set_task_comm(struct task_struct *tsk, char *from);
1864extern char *get_task_comm(char *to, struct task_struct *tsk);
1865
1866#ifdef CONFIG_SMP
1867extern void wait_task_inactive(struct task_struct * p);
1868#else
1869#define wait_task_inactive(p)	do { } while (0)
1870#endif
1871
1872#define remove_parent(p)	list_del_init(&(p)->sibling)
1873#define add_parent(p)		list_add_tail(&(p)->sibling,&(p)->parent->children)
1874
1875#define next_task(p)	list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
1876
1877#define for_each_process(p) \
1878	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1879
1880/*
1881 * Careful: do_each_thread/while_each_thread is a double loop so
1882 *          'break' will not work as expected - use goto instead.
1883 */
1884#define do_each_thread(g, t) \
1885	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1886
1887#define while_each_thread(g, t) \
1888	while ((t = next_thread(t)) != g)
1889
1890/* de_thread depends on thread_group_leader not being a pid based check */
1891#define thread_group_leader(p)	(p == p->group_leader)
1892
1893/* Do to the insanities of de_thread it is possible for a process
1894 * to have the pid of the thread group leader without actually being
1895 * the thread group leader.  For iteration through the pids in proc
1896 * all we care about is that we have a task with the appropriate
1897 * pid, we don't actually care if we have the right task.
1898 */
1899static inline int has_group_leader_pid(struct task_struct *p)
1900{
1901	return p->pid == p->tgid;
1902}
1903
1904static inline
1905int same_thread_group(struct task_struct *p1, struct task_struct *p2)
1906{
1907	return p1->tgid == p2->tgid;
1908}
1909
1910static inline struct task_struct *next_thread(const struct task_struct *p)
1911{
1912	return list_entry(rcu_dereference(p->thread_group.next),
1913			  struct task_struct, thread_group);
1914}
1915
1916static inline int thread_group_empty(struct task_struct *p)
1917{
1918	return list_empty(&p->thread_group);
1919}
1920
1921#define delay_group_leader(p) \
1922		(thread_group_leader(p) && !thread_group_empty(p))
1923
1924/*
1925 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
1926 * subscriptions and synchronises with wait4().  Also used in procfs.  Also
1927 * pins the final release of task.io_context.  Also protects ->cpuset and
1928 * ->cgroup.subsys[].
1929 *
1930 * Nests both inside and outside of read_lock(&tasklist_lock).
1931 * It must not be nested with write_lock_irq(&tasklist_lock),
1932 * neither inside nor outside.
1933 */
1934static inline void task_lock(struct task_struct *p)
1935{
1936	spin_lock(&p->alloc_lock);
1937}
1938
1939static inline void task_unlock(struct task_struct *p)
1940{
1941	spin_unlock(&p->alloc_lock);
1942}
1943
1944extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
1945							unsigned long *flags);
1946
1947static inline void unlock_task_sighand(struct task_struct *tsk,
1948						unsigned long *flags)
1949{
1950	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
1951}
1952
1953#ifndef __HAVE_THREAD_FUNCTIONS
1954
1955#define task_thread_info(task)	((struct thread_info *)(task)->stack)
1956#define task_stack_page(task)	((task)->stack)
1957
1958static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
1959{
1960	*task_thread_info(p) = *task_thread_info(org);
1961	task_thread_info(p)->task = p;
1962}
1963
1964static inline unsigned long *end_of_stack(struct task_struct *p)
1965{
1966	return (unsigned long *)(task_thread_info(p) + 1);
1967}
1968
1969#endif
1970
1971extern void thread_info_cache_init(void);
1972
1973/* set thread flags in other task's structures
1974 * - see asm/thread_info.h for TIF_xxxx flags available
1975 */
1976static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1977{
1978	set_ti_thread_flag(task_thread_info(tsk), flag);
1979}
1980
1981static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1982{
1983	clear_ti_thread_flag(task_thread_info(tsk), flag);
1984}
1985
1986static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1987{
1988	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1989}
1990
1991static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1992{
1993	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1994}
1995
1996static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1997{
1998	return test_ti_thread_flag(task_thread_info(tsk), flag);
1999}
2000
2001static inline void set_tsk_need_resched(struct task_struct *tsk)
2002{
2003	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2004}
2005
2006static inline void clear_tsk_need_resched(struct task_struct *tsk)
2007{
2008	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2009}
2010
2011static inline int test_tsk_need_resched(struct task_struct *tsk)
2012{
2013	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2014}
2015
2016static inline int signal_pending(struct task_struct *p)
2017{
2018	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2019}
2020
2021extern int __fatal_signal_pending(struct task_struct *p);
2022
2023static inline int fatal_signal_pending(struct task_struct *p)
2024{
2025	return signal_pending(p) && __fatal_signal_pending(p);
2026}
2027
2028static inline int need_resched(void)
2029{
2030	return unlikely(test_thread_flag(TIF_NEED_RESCHED));
2031}
2032
2033/*
2034 * cond_resched() and cond_resched_lock(): latency reduction via
2035 * explicit rescheduling in places that are safe. The return
2036 * value indicates whether a reschedule was done in fact.
2037 * cond_resched_lock() will drop the spinlock before scheduling,
2038 * cond_resched_softirq() will enable bhs before scheduling.
2039 */
2040extern int _cond_resched(void);
2041#ifdef CONFIG_PREEMPT_BKL
2042static inline int cond_resched(void)
2043{
2044	return 0;
2045}
2046#else
2047static inline int cond_resched(void)
2048{
2049	return _cond_resched();
2050}
2051#endif
2052extern int cond_resched_lock(spinlock_t * lock);
2053extern int cond_resched_softirq(void);
2054static inline int cond_resched_bkl(void)
2055{
2056	return _cond_resched();
2057}
2058
2059/*
2060 * Does a critical section need to be broken due to another
2061 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2062 * but a general need for low latency)
2063 */
2064static inline int spin_needbreak(spinlock_t *lock)
2065{
2066#ifdef CONFIG_PREEMPT
2067	return spin_is_contended(lock);
2068#else
2069	return 0;
2070#endif
2071}
2072
2073/*
2074 * Reevaluate whether the task has signals pending delivery.
2075 * Wake the task if so.
2076 * This is required every time the blocked sigset_t changes.
2077 * callers must hold sighand->siglock.
2078 */
2079extern void recalc_sigpending_and_wake(struct task_struct *t);
2080extern void recalc_sigpending(void);
2081
2082extern void signal_wake_up(struct task_struct *t, int resume_stopped);
2083
2084/*
2085 * Wrappers for p->thread_info->cpu access. No-op on UP.
2086 */
2087#ifdef CONFIG_SMP
2088
2089static inline unsigned int task_cpu(const struct task_struct *p)
2090{
2091	return task_thread_info(p)->cpu;
2092}
2093
2094extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2095
2096#else
2097
2098static inline unsigned int task_cpu(const struct task_struct *p)
2099{
2100	return 0;
2101}
2102
2103static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2104{
2105}
2106
2107#endif /* CONFIG_SMP */
2108
2109#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
2110extern void arch_pick_mmap_layout(struct mm_struct *mm);
2111#else
2112static inline void arch_pick_mmap_layout(struct mm_struct *mm)
2113{
2114	mm->mmap_base = TASK_UNMAPPED_BASE;
2115	mm->get_unmapped_area = arch_get_unmapped_area;
2116	mm->unmap_area = arch_unmap_area;
2117}
2118#endif
2119
2120extern long sched_setaffinity(pid_t pid, const cpumask_t *new_mask);
2121extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
2122
2123extern int sched_mc_power_savings, sched_smt_power_savings;
2124
2125extern void normalize_rt_tasks(void);
2126
2127#ifdef CONFIG_GROUP_SCHED
2128
2129extern struct task_group init_task_group;
2130#ifdef CONFIG_USER_SCHED
2131extern struct task_group root_task_group;
2132#endif
2133
2134extern struct task_group *sched_create_group(struct task_group *parent);
2135extern void sched_destroy_group(struct task_group *tg);
2136extern void sched_move_task(struct task_struct *tsk);
2137#ifdef CONFIG_FAIR_GROUP_SCHED
2138extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2139extern unsigned long sched_group_shares(struct task_group *tg);
2140#endif
2141#ifdef CONFIG_RT_GROUP_SCHED
2142extern int sched_group_set_rt_runtime(struct task_group *tg,
2143				      long rt_runtime_us);
2144extern long sched_group_rt_runtime(struct task_group *tg);
2145extern int sched_group_set_rt_period(struct task_group *tg,
2146				      long rt_period_us);
2147extern long sched_group_rt_period(struct task_group *tg);
2148#endif
2149#endif
2150
2151#ifdef CONFIG_TASK_XACCT
2152static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2153{
2154	tsk->rchar += amt;
2155}
2156
2157static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2158{
2159	tsk->wchar += amt;
2160}
2161
2162static inline void inc_syscr(struct task_struct *tsk)
2163{
2164	tsk->syscr++;
2165}
2166
2167static inline void inc_syscw(struct task_struct *tsk)
2168{
2169	tsk->syscw++;
2170}
2171#else
2172static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2173{
2174}
2175
2176static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2177{
2178}
2179
2180static inline void inc_syscr(struct task_struct *tsk)
2181{
2182}
2183
2184static inline void inc_syscw(struct task_struct *tsk)
2185{
2186}
2187#endif
2188
2189#ifdef CONFIG_SMP
2190void migration_init(void);
2191#else
2192static inline void migration_init(void)
2193{
2194}
2195#endif
2196
2197#ifndef TASK_SIZE_OF
2198#define TASK_SIZE_OF(tsk)	TASK_SIZE
2199#endif
2200
2201#ifdef CONFIG_MM_OWNER
2202extern void mm_update_next_owner(struct mm_struct *mm);
2203extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2204#else
2205static inline void mm_update_next_owner(struct mm_struct *mm)
2206{
2207}
2208
2209static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2210{
2211}
2212#endif /* CONFIG_MM_OWNER */
2213
2214#endif /* __KERNEL__ */
2215
2216#endif
2217