sched.h revision 7cd9013be6c22f3ff6f777354f766c8c0b955e17
1#ifndef _LINUX_SCHED_H
2#define _LINUX_SCHED_H
3
4#include <asm/param.h>	/* for HZ */
5
6#include <linux/config.h>
7#include <linux/capability.h>
8#include <linux/threads.h>
9#include <linux/kernel.h>
10#include <linux/types.h>
11#include <linux/timex.h>
12#include <linux/jiffies.h>
13#include <linux/rbtree.h>
14#include <linux/thread_info.h>
15#include <linux/cpumask.h>
16#include <linux/errno.h>
17#include <linux/nodemask.h>
18
19#include <asm/system.h>
20#include <asm/semaphore.h>
21#include <asm/page.h>
22#include <asm/ptrace.h>
23#include <asm/mmu.h>
24#include <asm/cputime.h>
25
26#include <linux/smp.h>
27#include <linux/sem.h>
28#include <linux/signal.h>
29#include <linux/securebits.h>
30#include <linux/fs_struct.h>
31#include <linux/compiler.h>
32#include <linux/completion.h>
33#include <linux/pid.h>
34#include <linux/percpu.h>
35#include <linux/topology.h>
36#include <linux/seccomp.h>
37#include <linux/rcupdate.h>
38
39#include <linux/auxvec.h>	/* For AT_VECTOR_SIZE */
40
41struct exec_domain;
42
43/*
44 * cloning flags:
45 */
46#define CSIGNAL		0x000000ff	/* signal mask to be sent at exit */
47#define CLONE_VM	0x00000100	/* set if VM shared between processes */
48#define CLONE_FS	0x00000200	/* set if fs info shared between processes */
49#define CLONE_FILES	0x00000400	/* set if open files shared between processes */
50#define CLONE_SIGHAND	0x00000800	/* set if signal handlers and blocked signals shared */
51#define CLONE_PTRACE	0x00002000	/* set if we want to let tracing continue on the child too */
52#define CLONE_VFORK	0x00004000	/* set if the parent wants the child to wake it up on mm_release */
53#define CLONE_PARENT	0x00008000	/* set if we want to have the same parent as the cloner */
54#define CLONE_THREAD	0x00010000	/* Same thread group? */
55#define CLONE_NEWNS	0x00020000	/* New namespace group? */
56#define CLONE_SYSVSEM	0x00040000	/* share system V SEM_UNDO semantics */
57#define CLONE_SETTLS	0x00080000	/* create a new TLS for the child */
58#define CLONE_PARENT_SETTID	0x00100000	/* set the TID in the parent */
59#define CLONE_CHILD_CLEARTID	0x00200000	/* clear the TID in the child */
60#define CLONE_DETACHED		0x00400000	/* Unused, ignored */
61#define CLONE_UNTRACED		0x00800000	/* set if the tracing process can't force CLONE_PTRACE on this clone */
62#define CLONE_CHILD_SETTID	0x01000000	/* set the TID in the child */
63#define CLONE_STOPPED		0x02000000	/* Start in stopped state */
64
65/*
66 * List of flags we want to share for kernel threads,
67 * if only because they are not used by them anyway.
68 */
69#define CLONE_KERNEL	(CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
70
71/*
72 * These are the constant used to fake the fixed-point load-average
73 * counting. Some notes:
74 *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
75 *    a load-average precision of 10 bits integer + 11 bits fractional
76 *  - if you want to count load-averages more often, you need more
77 *    precision, or rounding will get you. With 2-second counting freq,
78 *    the EXP_n values would be 1981, 2034 and 2043 if still using only
79 *    11 bit fractions.
80 */
81extern unsigned long avenrun[];		/* Load averages */
82
83#define FSHIFT		11		/* nr of bits of precision */
84#define FIXED_1		(1<<FSHIFT)	/* 1.0 as fixed-point */
85#define LOAD_FREQ	(5*HZ)		/* 5 sec intervals */
86#define EXP_1		1884		/* 1/exp(5sec/1min) as fixed-point */
87#define EXP_5		2014		/* 1/exp(5sec/5min) */
88#define EXP_15		2037		/* 1/exp(5sec/15min) */
89
90#define CALC_LOAD(load,exp,n) \
91	load *= exp; \
92	load += n*(FIXED_1-exp); \
93	load >>= FSHIFT;
94
95extern unsigned long total_forks;
96extern int nr_threads;
97extern int last_pid;
98DECLARE_PER_CPU(unsigned long, process_counts);
99extern int nr_processes(void);
100extern unsigned long nr_running(void);
101extern unsigned long nr_uninterruptible(void);
102extern unsigned long nr_iowait(void);
103
104#include <linux/time.h>
105#include <linux/param.h>
106#include <linux/resource.h>
107#include <linux/timer.h>
108#include <linux/hrtimer.h>
109
110#include <asm/processor.h>
111
112/*
113 * Task state bitmask. NOTE! These bits are also
114 * encoded in fs/proc/array.c: get_task_state().
115 *
116 * We have two separate sets of flags: task->state
117 * is about runnability, while task->exit_state are
118 * about the task exiting. Confusing, but this way
119 * modifying one set can't modify the other one by
120 * mistake.
121 */
122#define TASK_RUNNING		0
123#define TASK_INTERRUPTIBLE	1
124#define TASK_UNINTERRUPTIBLE	2
125#define TASK_STOPPED		4
126#define TASK_TRACED		8
127/* in tsk->exit_state */
128#define EXIT_ZOMBIE		16
129#define EXIT_DEAD		32
130/* in tsk->state again */
131#define TASK_NONINTERACTIVE	64
132
133#define __set_task_state(tsk, state_value)		\
134	do { (tsk)->state = (state_value); } while (0)
135#define set_task_state(tsk, state_value)		\
136	set_mb((tsk)->state, (state_value))
137
138/*
139 * set_current_state() includes a barrier so that the write of current->state
140 * is correctly serialised wrt the caller's subsequent test of whether to
141 * actually sleep:
142 *
143 *	set_current_state(TASK_UNINTERRUPTIBLE);
144 *	if (do_i_need_to_sleep())
145 *		schedule();
146 *
147 * If the caller does not need such serialisation then use __set_current_state()
148 */
149#define __set_current_state(state_value)			\
150	do { current->state = (state_value); } while (0)
151#define set_current_state(state_value)		\
152	set_mb(current->state, (state_value))
153
154/* Task command name length */
155#define TASK_COMM_LEN 16
156
157/*
158 * Scheduling policies
159 */
160#define SCHED_NORMAL		0
161#define SCHED_FIFO		1
162#define SCHED_RR		2
163#define SCHED_BATCH		3
164
165struct sched_param {
166	int sched_priority;
167};
168
169#ifdef __KERNEL__
170
171#include <linux/spinlock.h>
172
173/*
174 * This serializes "schedule()" and also protects
175 * the run-queue from deletions/modifications (but
176 * _adding_ to the beginning of the run-queue has
177 * a separate lock).
178 */
179extern rwlock_t tasklist_lock;
180extern spinlock_t mmlist_lock;
181
182typedef struct task_struct task_t;
183
184extern void sched_init(void);
185extern void sched_init_smp(void);
186extern void init_idle(task_t *idle, int cpu);
187
188extern cpumask_t nohz_cpu_mask;
189
190extern void show_state(void);
191extern void show_regs(struct pt_regs *);
192
193/*
194 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
195 * task), SP is the stack pointer of the first frame that should be shown in the back
196 * trace (or NULL if the entire call-chain of the task should be shown).
197 */
198extern void show_stack(struct task_struct *task, unsigned long *sp);
199
200void io_schedule(void);
201long io_schedule_timeout(long timeout);
202
203extern void cpu_init (void);
204extern void trap_init(void);
205extern void update_process_times(int user);
206extern void scheduler_tick(void);
207
208#ifdef CONFIG_DETECT_SOFTLOCKUP
209extern void softlockup_tick(struct pt_regs *regs);
210extern void spawn_softlockup_task(void);
211extern void touch_softlockup_watchdog(void);
212#else
213static inline void softlockup_tick(struct pt_regs *regs)
214{
215}
216static inline void spawn_softlockup_task(void)
217{
218}
219static inline void touch_softlockup_watchdog(void)
220{
221}
222#endif
223
224
225/* Attach to any functions which should be ignored in wchan output. */
226#define __sched		__attribute__((__section__(".sched.text")))
227/* Is this address in the __sched functions? */
228extern int in_sched_functions(unsigned long addr);
229
230#define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
231extern signed long FASTCALL(schedule_timeout(signed long timeout));
232extern signed long schedule_timeout_interruptible(signed long timeout);
233extern signed long schedule_timeout_uninterruptible(signed long timeout);
234asmlinkage void schedule(void);
235
236struct namespace;
237
238/* Maximum number of active map areas.. This is a random (large) number */
239#define DEFAULT_MAX_MAP_COUNT	65536
240
241extern int sysctl_max_map_count;
242
243#include <linux/aio.h>
244
245extern unsigned long
246arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
247		       unsigned long, unsigned long);
248extern unsigned long
249arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
250			  unsigned long len, unsigned long pgoff,
251			  unsigned long flags);
252extern void arch_unmap_area(struct mm_struct *, unsigned long);
253extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
254
255#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
256/*
257 * The mm counters are not protected by its page_table_lock,
258 * so must be incremented atomically.
259 */
260#define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
261#define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
262#define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
263#define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
264#define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
265typedef atomic_long_t mm_counter_t;
266
267#else  /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
268/*
269 * The mm counters are protected by its page_table_lock,
270 * so can be incremented directly.
271 */
272#define set_mm_counter(mm, member, value) (mm)->_##member = (value)
273#define get_mm_counter(mm, member) ((mm)->_##member)
274#define add_mm_counter(mm, member, value) (mm)->_##member += (value)
275#define inc_mm_counter(mm, member) (mm)->_##member++
276#define dec_mm_counter(mm, member) (mm)->_##member--
277typedef unsigned long mm_counter_t;
278
279#endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
280
281#define get_mm_rss(mm)					\
282	(get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
283#define update_hiwater_rss(mm)	do {			\
284	unsigned long _rss = get_mm_rss(mm);		\
285	if ((mm)->hiwater_rss < _rss)			\
286		(mm)->hiwater_rss = _rss;		\
287} while (0)
288#define update_hiwater_vm(mm)	do {			\
289	if ((mm)->hiwater_vm < (mm)->total_vm)		\
290		(mm)->hiwater_vm = (mm)->total_vm;	\
291} while (0)
292
293struct mm_struct {
294	struct vm_area_struct * mmap;		/* list of VMAs */
295	struct rb_root mm_rb;
296	struct vm_area_struct * mmap_cache;	/* last find_vma result */
297	unsigned long (*get_unmapped_area) (struct file *filp,
298				unsigned long addr, unsigned long len,
299				unsigned long pgoff, unsigned long flags);
300	void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
301	unsigned long mmap_base;		/* base of mmap area */
302	unsigned long task_size;		/* size of task vm space */
303	unsigned long cached_hole_size;         /* if non-zero, the largest hole below free_area_cache */
304	unsigned long free_area_cache;		/* first hole of size cached_hole_size or larger */
305	pgd_t * pgd;
306	atomic_t mm_users;			/* How many users with user space? */
307	atomic_t mm_count;			/* How many references to "struct mm_struct" (users count as 1) */
308	int map_count;				/* number of VMAs */
309	struct rw_semaphore mmap_sem;
310	spinlock_t page_table_lock;		/* Protects page tables and some counters */
311
312	struct list_head mmlist;		/* List of maybe swapped mm's.  These are globally strung
313						 * together off init_mm.mmlist, and are protected
314						 * by mmlist_lock
315						 */
316
317	/* Special counters, in some configurations protected by the
318	 * page_table_lock, in other configurations by being atomic.
319	 */
320	mm_counter_t _file_rss;
321	mm_counter_t _anon_rss;
322
323	unsigned long hiwater_rss;	/* High-watermark of RSS usage */
324	unsigned long hiwater_vm;	/* High-water virtual memory usage */
325
326	unsigned long total_vm, locked_vm, shared_vm, exec_vm;
327	unsigned long stack_vm, reserved_vm, def_flags, nr_ptes;
328	unsigned long start_code, end_code, start_data, end_data;
329	unsigned long start_brk, brk, start_stack;
330	unsigned long arg_start, arg_end, env_start, env_end;
331
332	unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
333
334	unsigned dumpable:2;
335	cpumask_t cpu_vm_mask;
336
337	/* Architecture-specific MM context */
338	mm_context_t context;
339
340	/* Token based thrashing protection. */
341	unsigned long swap_token_time;
342	char recent_pagein;
343
344	/* coredumping support */
345	int core_waiters;
346	struct completion *core_startup_done, core_done;
347
348	/* aio bits */
349	rwlock_t		ioctx_list_lock;
350	struct kioctx		*ioctx_list;
351};
352
353struct sighand_struct {
354	atomic_t		count;
355	struct k_sigaction	action[_NSIG];
356	spinlock_t		siglock;
357	struct rcu_head		rcu;
358};
359
360extern void sighand_free_cb(struct rcu_head *rhp);
361
362static inline void sighand_free(struct sighand_struct *sp)
363{
364	call_rcu(&sp->rcu, sighand_free_cb);
365}
366
367/*
368 * NOTE! "signal_struct" does not have it's own
369 * locking, because a shared signal_struct always
370 * implies a shared sighand_struct, so locking
371 * sighand_struct is always a proper superset of
372 * the locking of signal_struct.
373 */
374struct signal_struct {
375	atomic_t		count;
376	atomic_t		live;
377
378	wait_queue_head_t	wait_chldexit;	/* for wait4() */
379
380	/* current thread group signal load-balancing target: */
381	task_t			*curr_target;
382
383	/* shared signal handling: */
384	struct sigpending	shared_pending;
385
386	/* thread group exit support */
387	int			group_exit_code;
388	/* overloaded:
389	 * - notify group_exit_task when ->count is equal to notify_count
390	 * - everyone except group_exit_task is stopped during signal delivery
391	 *   of fatal signals, group_exit_task processes the signal.
392	 */
393	struct task_struct	*group_exit_task;
394	int			notify_count;
395
396	/* thread group stop support, overloads group_exit_code too */
397	int			group_stop_count;
398	unsigned int		flags; /* see SIGNAL_* flags below */
399
400	/* POSIX.1b Interval Timers */
401	struct list_head posix_timers;
402
403	/* ITIMER_REAL timer for the process */
404	struct hrtimer real_timer;
405	ktime_t it_real_incr;
406
407	/* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
408	cputime_t it_prof_expires, it_virt_expires;
409	cputime_t it_prof_incr, it_virt_incr;
410
411	/* job control IDs */
412	pid_t pgrp;
413	pid_t tty_old_pgrp;
414	pid_t session;
415	/* boolean value for session group leader */
416	int leader;
417
418	struct tty_struct *tty; /* NULL if no tty */
419
420	/*
421	 * Cumulative resource counters for dead threads in the group,
422	 * and for reaped dead child processes forked by this group.
423	 * Live threads maintain their own counters and add to these
424	 * in __exit_signal, except for the group leader.
425	 */
426	cputime_t utime, stime, cutime, cstime;
427	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
428	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
429
430	/*
431	 * Cumulative ns of scheduled CPU time for dead threads in the
432	 * group, not including a zombie group leader.  (This only differs
433	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
434	 * other than jiffies.)
435	 */
436	unsigned long long sched_time;
437
438	/*
439	 * We don't bother to synchronize most readers of this at all,
440	 * because there is no reader checking a limit that actually needs
441	 * to get both rlim_cur and rlim_max atomically, and either one
442	 * alone is a single word that can safely be read normally.
443	 * getrlimit/setrlimit use task_lock(current->group_leader) to
444	 * protect this instead of the siglock, because they really
445	 * have no need to disable irqs.
446	 */
447	struct rlimit rlim[RLIM_NLIMITS];
448
449	struct list_head cpu_timers[3];
450
451	/* keep the process-shared keyrings here so that they do the right
452	 * thing in threads created with CLONE_THREAD */
453#ifdef CONFIG_KEYS
454	struct key *session_keyring;	/* keyring inherited over fork */
455	struct key *process_keyring;	/* keyring private to this process */
456#endif
457};
458
459/* Context switch must be unlocked if interrupts are to be enabled */
460#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
461# define __ARCH_WANT_UNLOCKED_CTXSW
462#endif
463
464/*
465 * Bits in flags field of signal_struct.
466 */
467#define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
468#define SIGNAL_STOP_DEQUEUED	0x00000002 /* stop signal dequeued */
469#define SIGNAL_STOP_CONTINUED	0x00000004 /* SIGCONT since WCONTINUED reap */
470#define SIGNAL_GROUP_EXIT	0x00000008 /* group exit in progress */
471
472
473/*
474 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
475 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
476 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
477 * values are inverted: lower p->prio value means higher priority.
478 *
479 * The MAX_USER_RT_PRIO value allows the actual maximum
480 * RT priority to be separate from the value exported to
481 * user-space.  This allows kernel threads to set their
482 * priority to a value higher than any user task. Note:
483 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
484 */
485
486#define MAX_USER_RT_PRIO	100
487#define MAX_RT_PRIO		MAX_USER_RT_PRIO
488
489#define MAX_PRIO		(MAX_RT_PRIO + 40)
490
491#define rt_task(p)		(unlikely((p)->prio < MAX_RT_PRIO))
492
493/*
494 * Some day this will be a full-fledged user tracking system..
495 */
496struct user_struct {
497	atomic_t __count;	/* reference count */
498	atomic_t processes;	/* How many processes does this user have? */
499	atomic_t files;		/* How many open files does this user have? */
500	atomic_t sigpending;	/* How many pending signals does this user have? */
501#ifdef CONFIG_INOTIFY
502	atomic_t inotify_watches; /* How many inotify watches does this user have? */
503	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
504#endif
505	/* protected by mq_lock	*/
506	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
507	unsigned long locked_shm; /* How many pages of mlocked shm ? */
508
509#ifdef CONFIG_KEYS
510	struct key *uid_keyring;	/* UID specific keyring */
511	struct key *session_keyring;	/* UID's default session keyring */
512#endif
513
514	/* Hash table maintenance information */
515	struct list_head uidhash_list;
516	uid_t uid;
517};
518
519extern struct user_struct *find_user(uid_t);
520
521extern struct user_struct root_user;
522#define INIT_USER (&root_user)
523
524typedef struct prio_array prio_array_t;
525struct backing_dev_info;
526struct reclaim_state;
527
528#ifdef CONFIG_SCHEDSTATS
529struct sched_info {
530	/* cumulative counters */
531	unsigned long	cpu_time,	/* time spent on the cpu */
532			run_delay,	/* time spent waiting on a runqueue */
533			pcnt;		/* # of timeslices run on this cpu */
534
535	/* timestamps */
536	unsigned long	last_arrival,	/* when we last ran on a cpu */
537			last_queued;	/* when we were last queued to run */
538};
539
540extern struct file_operations proc_schedstat_operations;
541#endif
542
543enum idle_type
544{
545	SCHED_IDLE,
546	NOT_IDLE,
547	NEWLY_IDLE,
548	MAX_IDLE_TYPES
549};
550
551/*
552 * sched-domains (multiprocessor balancing) declarations:
553 */
554#ifdef CONFIG_SMP
555#define SCHED_LOAD_SCALE	128UL	/* increase resolution of load */
556
557#define SD_LOAD_BALANCE		1	/* Do load balancing on this domain. */
558#define SD_BALANCE_NEWIDLE	2	/* Balance when about to become idle */
559#define SD_BALANCE_EXEC		4	/* Balance on exec */
560#define SD_BALANCE_FORK		8	/* Balance on fork, clone */
561#define SD_WAKE_IDLE		16	/* Wake to idle CPU on task wakeup */
562#define SD_WAKE_AFFINE		32	/* Wake task to waking CPU */
563#define SD_WAKE_BALANCE		64	/* Perform balancing at task wakeup */
564#define SD_SHARE_CPUPOWER	128	/* Domain members share cpu power */
565
566struct sched_group {
567	struct sched_group *next;	/* Must be a circular list */
568	cpumask_t cpumask;
569
570	/*
571	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
572	 * single CPU. This is read only (except for setup, hotplug CPU).
573	 */
574	unsigned long cpu_power;
575};
576
577struct sched_domain {
578	/* These fields must be setup */
579	struct sched_domain *parent;	/* top domain must be null terminated */
580	struct sched_group *groups;	/* the balancing groups of the domain */
581	cpumask_t span;			/* span of all CPUs in this domain */
582	unsigned long min_interval;	/* Minimum balance interval ms */
583	unsigned long max_interval;	/* Maximum balance interval ms */
584	unsigned int busy_factor;	/* less balancing by factor if busy */
585	unsigned int imbalance_pct;	/* No balance until over watermark */
586	unsigned long long cache_hot_time; /* Task considered cache hot (ns) */
587	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
588	unsigned int per_cpu_gain;	/* CPU % gained by adding domain cpus */
589	unsigned int busy_idx;
590	unsigned int idle_idx;
591	unsigned int newidle_idx;
592	unsigned int wake_idx;
593	unsigned int forkexec_idx;
594	int flags;			/* See SD_* */
595
596	/* Runtime fields. */
597	unsigned long last_balance;	/* init to jiffies. units in jiffies */
598	unsigned int balance_interval;	/* initialise to 1. units in ms. */
599	unsigned int nr_balance_failed; /* initialise to 0 */
600
601#ifdef CONFIG_SCHEDSTATS
602	/* load_balance() stats */
603	unsigned long lb_cnt[MAX_IDLE_TYPES];
604	unsigned long lb_failed[MAX_IDLE_TYPES];
605	unsigned long lb_balanced[MAX_IDLE_TYPES];
606	unsigned long lb_imbalance[MAX_IDLE_TYPES];
607	unsigned long lb_gained[MAX_IDLE_TYPES];
608	unsigned long lb_hot_gained[MAX_IDLE_TYPES];
609	unsigned long lb_nobusyg[MAX_IDLE_TYPES];
610	unsigned long lb_nobusyq[MAX_IDLE_TYPES];
611
612	/* Active load balancing */
613	unsigned long alb_cnt;
614	unsigned long alb_failed;
615	unsigned long alb_pushed;
616
617	/* SD_BALANCE_EXEC stats */
618	unsigned long sbe_cnt;
619	unsigned long sbe_balanced;
620	unsigned long sbe_pushed;
621
622	/* SD_BALANCE_FORK stats */
623	unsigned long sbf_cnt;
624	unsigned long sbf_balanced;
625	unsigned long sbf_pushed;
626
627	/* try_to_wake_up() stats */
628	unsigned long ttwu_wake_remote;
629	unsigned long ttwu_move_affine;
630	unsigned long ttwu_move_balance;
631#endif
632};
633
634extern void partition_sched_domains(cpumask_t *partition1,
635				    cpumask_t *partition2);
636
637/*
638 * Maximum cache size the migration-costs auto-tuning code will
639 * search from:
640 */
641extern unsigned int max_cache_size;
642
643#endif	/* CONFIG_SMP */
644
645
646struct io_context;			/* See blkdev.h */
647void exit_io_context(void);
648struct cpuset;
649
650#define NGROUPS_SMALL		32
651#define NGROUPS_PER_BLOCK	((int)(PAGE_SIZE / sizeof(gid_t)))
652struct group_info {
653	int ngroups;
654	atomic_t usage;
655	gid_t small_block[NGROUPS_SMALL];
656	int nblocks;
657	gid_t *blocks[0];
658};
659
660/*
661 * get_group_info() must be called with the owning task locked (via task_lock())
662 * when task != current.  The reason being that the vast majority of callers are
663 * looking at current->group_info, which can not be changed except by the
664 * current task.  Changing current->group_info requires the task lock, too.
665 */
666#define get_group_info(group_info) do { \
667	atomic_inc(&(group_info)->usage); \
668} while (0)
669
670#define put_group_info(group_info) do { \
671	if (atomic_dec_and_test(&(group_info)->usage)) \
672		groups_free(group_info); \
673} while (0)
674
675extern struct group_info *groups_alloc(int gidsetsize);
676extern void groups_free(struct group_info *group_info);
677extern int set_current_groups(struct group_info *group_info);
678extern int groups_search(struct group_info *group_info, gid_t grp);
679/* access the groups "array" with this macro */
680#define GROUP_AT(gi, i) \
681    ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
682
683#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
684extern void prefetch_stack(struct task_struct*);
685#else
686static inline void prefetch_stack(struct task_struct *t) { }
687#endif
688
689struct audit_context;		/* See audit.c */
690struct mempolicy;
691
692struct task_struct {
693	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
694	struct thread_info *thread_info;
695	atomic_t usage;
696	unsigned long flags;	/* per process flags, defined below */
697	unsigned long ptrace;
698
699	int lock_depth;		/* BKL lock depth */
700
701#if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW)
702	int oncpu;
703#endif
704	int prio, static_prio;
705	struct list_head run_list;
706	prio_array_t *array;
707
708	unsigned short ioprio;
709
710	unsigned long sleep_avg;
711	unsigned long long timestamp, last_ran;
712	unsigned long long sched_time; /* sched_clock time spent running */
713	int activated;
714
715	unsigned long policy;
716	cpumask_t cpus_allowed;
717	unsigned int time_slice, first_time_slice;
718
719#ifdef CONFIG_SCHEDSTATS
720	struct sched_info sched_info;
721#endif
722
723	struct list_head tasks;
724	/*
725	 * ptrace_list/ptrace_children forms the list of my children
726	 * that were stolen by a ptracer.
727	 */
728	struct list_head ptrace_children;
729	struct list_head ptrace_list;
730
731	struct mm_struct *mm, *active_mm;
732
733/* task state */
734	struct linux_binfmt *binfmt;
735	long exit_state;
736	int exit_code, exit_signal;
737	int pdeath_signal;  /*  The signal sent when the parent dies  */
738	/* ??? */
739	unsigned long personality;
740	unsigned did_exec:1;
741	pid_t pid;
742	pid_t tgid;
743	/*
744	 * pointers to (original) parent process, youngest child, younger sibling,
745	 * older sibling, respectively.  (p->father can be replaced with
746	 * p->parent->pid)
747	 */
748	struct task_struct *real_parent; /* real parent process (when being debugged) */
749	struct task_struct *parent;	/* parent process */
750	/*
751	 * children/sibling forms the list of my children plus the
752	 * tasks I'm ptracing.
753	 */
754	struct list_head children;	/* list of my children */
755	struct list_head sibling;	/* linkage in my parent's children list */
756	struct task_struct *group_leader;	/* threadgroup leader */
757
758	/* PID/PID hash table linkage. */
759	struct pid pids[PIDTYPE_MAX];
760
761	struct completion *vfork_done;		/* for vfork() */
762	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
763	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
764
765	unsigned long rt_priority;
766	cputime_t utime, stime;
767	unsigned long nvcsw, nivcsw; /* context switch counts */
768	struct timespec start_time;
769/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
770	unsigned long min_flt, maj_flt;
771
772  	cputime_t it_prof_expires, it_virt_expires;
773	unsigned long long it_sched_expires;
774	struct list_head cpu_timers[3];
775
776/* process credentials */
777	uid_t uid,euid,suid,fsuid;
778	gid_t gid,egid,sgid,fsgid;
779	struct group_info *group_info;
780	kernel_cap_t   cap_effective, cap_inheritable, cap_permitted;
781	unsigned keep_capabilities:1;
782	struct user_struct *user;
783#ifdef CONFIG_KEYS
784	struct key *request_key_auth;	/* assumed request_key authority */
785	struct key *thread_keyring;	/* keyring private to this thread */
786	unsigned char jit_keyring;	/* default keyring to attach requested keys to */
787#endif
788	int oomkilladj; /* OOM kill score adjustment (bit shift). */
789	char comm[TASK_COMM_LEN]; /* executable name excluding path
790				     - access with [gs]et_task_comm (which lock
791				       it with task_lock())
792				     - initialized normally by flush_old_exec */
793/* file system info */
794	int link_count, total_link_count;
795/* ipc stuff */
796	struct sysv_sem sysvsem;
797/* CPU-specific state of this task */
798	struct thread_struct thread;
799/* filesystem information */
800	struct fs_struct *fs;
801/* open file information */
802	struct files_struct *files;
803/* namespace */
804	struct namespace *namespace;
805/* signal handlers */
806	struct signal_struct *signal;
807	struct sighand_struct *sighand;
808
809	sigset_t blocked, real_blocked;
810	sigset_t saved_sigmask;		/* To be restored with TIF_RESTORE_SIGMASK */
811	struct sigpending pending;
812
813	unsigned long sas_ss_sp;
814	size_t sas_ss_size;
815	int (*notifier)(void *priv);
816	void *notifier_data;
817	sigset_t *notifier_mask;
818
819	void *security;
820	struct audit_context *audit_context;
821	seccomp_t seccomp;
822
823/* Thread group tracking */
824   	u32 parent_exec_id;
825   	u32 self_exec_id;
826/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
827	spinlock_t alloc_lock;
828/* Protection of proc_dentry: nesting proc_lock, dcache_lock, write_lock_irq(&tasklist_lock); */
829	spinlock_t proc_lock;
830
831#ifdef CONFIG_DEBUG_MUTEXES
832	/* mutex deadlock detection */
833	struct mutex_waiter *blocked_on;
834#endif
835
836/* journalling filesystem info */
837	void *journal_info;
838
839/* VM state */
840	struct reclaim_state *reclaim_state;
841
842	struct dentry *proc_dentry;
843	struct backing_dev_info *backing_dev_info;
844
845	struct io_context *io_context;
846
847	unsigned long ptrace_message;
848	siginfo_t *last_siginfo; /* For ptrace use.  */
849/*
850 * current io wait handle: wait queue entry to use for io waits
851 * If this thread is processing aio, this points at the waitqueue
852 * inside the currently handled kiocb. It may be NULL (i.e. default
853 * to a stack based synchronous wait) if its doing sync IO.
854 */
855	wait_queue_t *io_wait;
856/* i/o counters(bytes read/written, #syscalls */
857	u64 rchar, wchar, syscr, syscw;
858#if defined(CONFIG_BSD_PROCESS_ACCT)
859	u64 acct_rss_mem1;	/* accumulated rss usage */
860	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
861	clock_t acct_stimexpd;	/* clock_t-converted stime since last update */
862#endif
863#ifdef CONFIG_NUMA
864  	struct mempolicy *mempolicy;
865	short il_next;
866#endif
867#ifdef CONFIG_CPUSETS
868	struct cpuset *cpuset;
869	nodemask_t mems_allowed;
870	int cpuset_mems_generation;
871#endif
872	atomic_t fs_excl;	/* holding fs exclusive resources */
873	struct rcu_head rcu;
874};
875
876static inline pid_t process_group(struct task_struct *tsk)
877{
878	return tsk->signal->pgrp;
879}
880
881/**
882 * pid_alive - check that a task structure is not stale
883 * @p: Task structure to be checked.
884 *
885 * Test if a process is not yet dead (at most zombie state)
886 * If pid_alive fails, then pointers within the task structure
887 * can be stale and must not be dereferenced.
888 */
889static inline int pid_alive(struct task_struct *p)
890{
891	return p->pids[PIDTYPE_PID].nr != 0;
892}
893
894extern void free_task(struct task_struct *tsk);
895#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
896
897extern void __put_task_struct_cb(struct rcu_head *rhp);
898
899static inline void put_task_struct(struct task_struct *t)
900{
901	if (atomic_dec_and_test(&t->usage))
902		call_rcu(&t->rcu, __put_task_struct_cb);
903}
904
905/*
906 * Per process flags
907 */
908#define PF_ALIGNWARN	0x00000001	/* Print alignment warning msgs */
909					/* Not implemented yet, only for 486*/
910#define PF_STARTING	0x00000002	/* being created */
911#define PF_EXITING	0x00000004	/* getting shut down */
912#define PF_DEAD		0x00000008	/* Dead */
913#define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
914#define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
915#define PF_DUMPCORE	0x00000200	/* dumped core */
916#define PF_SIGNALED	0x00000400	/* killed by a signal */
917#define PF_MEMALLOC	0x00000800	/* Allocating memory */
918#define PF_FLUSHER	0x00001000	/* responsible for disk writeback */
919#define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
920#define PF_FREEZE	0x00004000	/* this task is being frozen for suspend now */
921#define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
922#define PF_FROZEN	0x00010000	/* frozen for system suspend */
923#define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
924#define PF_KSWAPD	0x00040000	/* I am kswapd */
925#define PF_SWAPOFF	0x00080000	/* I am in swapoff */
926#define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
927#define PF_SYNCWRITE	0x00200000	/* I am doing a sync write */
928#define PF_BORROWED_MM	0x00400000	/* I am a kthread doing use_mm */
929#define PF_RANDOMIZE	0x00800000	/* randomize virtual address space */
930#define PF_SWAPWRITE	0x01000000	/* Allowed to write to swap */
931
932/*
933 * Only the _current_ task can read/write to tsk->flags, but other
934 * tasks can access tsk->flags in readonly mode for example
935 * with tsk_used_math (like during threaded core dumping).
936 * There is however an exception to this rule during ptrace
937 * or during fork: the ptracer task is allowed to write to the
938 * child->flags of its traced child (same goes for fork, the parent
939 * can write to the child->flags), because we're guaranteed the
940 * child is not running and in turn not changing child->flags
941 * at the same time the parent does it.
942 */
943#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
944#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
945#define clear_used_math() clear_stopped_child_used_math(current)
946#define set_used_math() set_stopped_child_used_math(current)
947#define conditional_stopped_child_used_math(condition, child) \
948	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
949#define conditional_used_math(condition) \
950	conditional_stopped_child_used_math(condition, current)
951#define copy_to_stopped_child_used_math(child) \
952	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
953/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
954#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
955#define used_math() tsk_used_math(current)
956
957#ifdef CONFIG_SMP
958extern int set_cpus_allowed(task_t *p, cpumask_t new_mask);
959#else
960static inline int set_cpus_allowed(task_t *p, cpumask_t new_mask)
961{
962	if (!cpu_isset(0, new_mask))
963		return -EINVAL;
964	return 0;
965}
966#endif
967
968extern unsigned long long sched_clock(void);
969extern unsigned long long current_sched_time(const task_t *current_task);
970
971/* sched_exec is called by processes performing an exec */
972#ifdef CONFIG_SMP
973extern void sched_exec(void);
974#else
975#define sched_exec()   {}
976#endif
977
978#ifdef CONFIG_HOTPLUG_CPU
979extern void idle_task_exit(void);
980#else
981static inline void idle_task_exit(void) {}
982#endif
983
984extern void sched_idle_next(void);
985extern void set_user_nice(task_t *p, long nice);
986extern int task_prio(const task_t *p);
987extern int task_nice(const task_t *p);
988extern int can_nice(const task_t *p, const int nice);
989extern int task_curr(const task_t *p);
990extern int idle_cpu(int cpu);
991extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
992extern task_t *idle_task(int cpu);
993extern task_t *curr_task(int cpu);
994extern void set_curr_task(int cpu, task_t *p);
995
996void yield(void);
997
998/*
999 * The default (Linux) execution domain.
1000 */
1001extern struct exec_domain	default_exec_domain;
1002
1003union thread_union {
1004	struct thread_info thread_info;
1005	unsigned long stack[THREAD_SIZE/sizeof(long)];
1006};
1007
1008#ifndef __HAVE_ARCH_KSTACK_END
1009static inline int kstack_end(void *addr)
1010{
1011	/* Reliable end of stack detection:
1012	 * Some APM bios versions misalign the stack
1013	 */
1014	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1015}
1016#endif
1017
1018extern union thread_union init_thread_union;
1019extern struct task_struct init_task;
1020
1021extern struct   mm_struct init_mm;
1022
1023#define find_task_by_pid(nr)	find_task_by_pid_type(PIDTYPE_PID, nr)
1024extern struct task_struct *find_task_by_pid_type(int type, int pid);
1025extern void set_special_pids(pid_t session, pid_t pgrp);
1026extern void __set_special_pids(pid_t session, pid_t pgrp);
1027
1028/* per-UID process charging. */
1029extern struct user_struct * alloc_uid(uid_t);
1030static inline struct user_struct *get_uid(struct user_struct *u)
1031{
1032	atomic_inc(&u->__count);
1033	return u;
1034}
1035extern void free_uid(struct user_struct *);
1036extern void switch_uid(struct user_struct *);
1037
1038#include <asm/current.h>
1039
1040extern void do_timer(struct pt_regs *);
1041
1042extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state));
1043extern int FASTCALL(wake_up_process(struct task_struct * tsk));
1044extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
1045						unsigned long clone_flags));
1046#ifdef CONFIG_SMP
1047 extern void kick_process(struct task_struct *tsk);
1048#else
1049 static inline void kick_process(struct task_struct *tsk) { }
1050#endif
1051extern void FASTCALL(sched_fork(task_t * p, int clone_flags));
1052extern void FASTCALL(sched_exit(task_t * p));
1053
1054extern int in_group_p(gid_t);
1055extern int in_egroup_p(gid_t);
1056
1057extern void proc_caches_init(void);
1058extern void flush_signals(struct task_struct *);
1059extern void flush_signal_handlers(struct task_struct *, int force_default);
1060extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1061
1062static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1063{
1064	unsigned long flags;
1065	int ret;
1066
1067	spin_lock_irqsave(&tsk->sighand->siglock, flags);
1068	ret = dequeue_signal(tsk, mask, info);
1069	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1070
1071	return ret;
1072}
1073
1074extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1075			      sigset_t *mask);
1076extern void unblock_all_signals(void);
1077extern void release_task(struct task_struct * p);
1078extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1079extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
1080extern int force_sigsegv(int, struct task_struct *);
1081extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1082extern int __kill_pg_info(int sig, struct siginfo *info, pid_t pgrp);
1083extern int kill_pg_info(int, struct siginfo *, pid_t);
1084extern int kill_proc_info(int, struct siginfo *, pid_t);
1085extern int kill_proc_info_as_uid(int, struct siginfo *, pid_t, uid_t, uid_t);
1086extern void do_notify_parent(struct task_struct *, int);
1087extern void force_sig(int, struct task_struct *);
1088extern void force_sig_specific(int, struct task_struct *);
1089extern int send_sig(int, struct task_struct *, int);
1090extern void zap_other_threads(struct task_struct *p);
1091extern int kill_pg(pid_t, int, int);
1092extern int kill_sl(pid_t, int, int);
1093extern int kill_proc(pid_t, int, int);
1094extern struct sigqueue *sigqueue_alloc(void);
1095extern void sigqueue_free(struct sigqueue *);
1096extern int send_sigqueue(int, struct sigqueue *,  struct task_struct *);
1097extern int send_group_sigqueue(int, struct sigqueue *,  struct task_struct *);
1098extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
1099extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1100
1101/* These can be the second arg to send_sig_info/send_group_sig_info.  */
1102#define SEND_SIG_NOINFO ((struct siginfo *) 0)
1103#define SEND_SIG_PRIV	((struct siginfo *) 1)
1104#define SEND_SIG_FORCED	((struct siginfo *) 2)
1105
1106static inline int is_si_special(const struct siginfo *info)
1107{
1108	return info <= SEND_SIG_FORCED;
1109}
1110
1111/* True if we are on the alternate signal stack.  */
1112
1113static inline int on_sig_stack(unsigned long sp)
1114{
1115	return (sp - current->sas_ss_sp < current->sas_ss_size);
1116}
1117
1118static inline int sas_ss_flags(unsigned long sp)
1119{
1120	return (current->sas_ss_size == 0 ? SS_DISABLE
1121		: on_sig_stack(sp) ? SS_ONSTACK : 0);
1122}
1123
1124/*
1125 * Routines for handling mm_structs
1126 */
1127extern struct mm_struct * mm_alloc(void);
1128
1129/* mmdrop drops the mm and the page tables */
1130extern void FASTCALL(__mmdrop(struct mm_struct *));
1131static inline void mmdrop(struct mm_struct * mm)
1132{
1133	if (atomic_dec_and_test(&mm->mm_count))
1134		__mmdrop(mm);
1135}
1136
1137/* mmput gets rid of the mappings and all user-space */
1138extern void mmput(struct mm_struct *);
1139/* Grab a reference to a task's mm, if it is not already going away */
1140extern struct mm_struct *get_task_mm(struct task_struct *task);
1141/* Remove the current tasks stale references to the old mm_struct */
1142extern void mm_release(struct task_struct *, struct mm_struct *);
1143
1144extern int  copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1145extern void flush_thread(void);
1146extern void exit_thread(void);
1147
1148extern void exit_files(struct task_struct *);
1149extern void exit_signal(struct task_struct *);
1150extern void __exit_signal(struct task_struct *);
1151extern void exit_sighand(struct task_struct *);
1152extern void __exit_sighand(struct task_struct *);
1153extern void exit_itimers(struct signal_struct *);
1154
1155extern NORET_TYPE void do_group_exit(int);
1156
1157extern void daemonize(const char *, ...);
1158extern int allow_signal(int);
1159extern int disallow_signal(int);
1160extern task_t *child_reaper;
1161
1162extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1163extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1164task_t *fork_idle(int);
1165
1166extern void set_task_comm(struct task_struct *tsk, char *from);
1167extern void get_task_comm(char *to, struct task_struct *tsk);
1168
1169#ifdef CONFIG_SMP
1170extern void wait_task_inactive(task_t * p);
1171#else
1172#define wait_task_inactive(p)	do { } while (0)
1173#endif
1174
1175#define remove_parent(p)	list_del_init(&(p)->sibling)
1176#define add_parent(p, parent)	list_add_tail(&(p)->sibling,&(parent)->children)
1177
1178#define REMOVE_LINKS(p) do {					\
1179	if (thread_group_leader(p))				\
1180		list_del_init(&(p)->tasks);			\
1181	remove_parent(p);					\
1182	} while (0)
1183
1184#define SET_LINKS(p) do {					\
1185	if (thread_group_leader(p))				\
1186		list_add_tail(&(p)->tasks,&init_task.tasks);	\
1187	add_parent(p, (p)->parent);				\
1188	} while (0)
1189
1190#define next_task(p)	list_entry((p)->tasks.next, struct task_struct, tasks)
1191#define prev_task(p)	list_entry((p)->tasks.prev, struct task_struct, tasks)
1192
1193#define for_each_process(p) \
1194	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1195
1196/*
1197 * Careful: do_each_thread/while_each_thread is a double loop so
1198 *          'break' will not work as expected - use goto instead.
1199 */
1200#define do_each_thread(g, t) \
1201	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1202
1203#define while_each_thread(g, t) \
1204	while ((t = next_thread(t)) != g)
1205
1206extern task_t * FASTCALL(next_thread(const task_t *p));
1207
1208#define thread_group_leader(p)	(p->pid == p->tgid)
1209
1210static inline int thread_group_empty(task_t *p)
1211{
1212	return list_empty(&p->pids[PIDTYPE_TGID].pid_list);
1213}
1214
1215#define delay_group_leader(p) \
1216		(thread_group_leader(p) && !thread_group_empty(p))
1217
1218extern void unhash_process(struct task_struct *p);
1219
1220/*
1221 * Protects ->fs, ->files, ->mm, ->ptrace, ->group_info, ->comm, keyring
1222 * subscriptions and synchronises with wait4().  Also used in procfs.  Also
1223 * pins the final release of task.io_context.  Also protects ->cpuset.
1224 *
1225 * Nests both inside and outside of read_lock(&tasklist_lock).
1226 * It must not be nested with write_lock_irq(&tasklist_lock),
1227 * neither inside nor outside.
1228 */
1229static inline void task_lock(struct task_struct *p)
1230{
1231	spin_lock(&p->alloc_lock);
1232}
1233
1234static inline void task_unlock(struct task_struct *p)
1235{
1236	spin_unlock(&p->alloc_lock);
1237}
1238
1239#ifndef __HAVE_THREAD_FUNCTIONS
1240
1241#define task_thread_info(task) (task)->thread_info
1242#define task_stack_page(task) ((void*)((task)->thread_info))
1243
1244static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
1245{
1246	*task_thread_info(p) = *task_thread_info(org);
1247	task_thread_info(p)->task = p;
1248}
1249
1250static inline unsigned long *end_of_stack(struct task_struct *p)
1251{
1252	return (unsigned long *)(p->thread_info + 1);
1253}
1254
1255#endif
1256
1257/* set thread flags in other task's structures
1258 * - see asm/thread_info.h for TIF_xxxx flags available
1259 */
1260static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1261{
1262	set_ti_thread_flag(task_thread_info(tsk), flag);
1263}
1264
1265static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1266{
1267	clear_ti_thread_flag(task_thread_info(tsk), flag);
1268}
1269
1270static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1271{
1272	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1273}
1274
1275static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1276{
1277	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1278}
1279
1280static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1281{
1282	return test_ti_thread_flag(task_thread_info(tsk), flag);
1283}
1284
1285static inline void set_tsk_need_resched(struct task_struct *tsk)
1286{
1287	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1288}
1289
1290static inline void clear_tsk_need_resched(struct task_struct *tsk)
1291{
1292	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1293}
1294
1295static inline int signal_pending(struct task_struct *p)
1296{
1297	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1298}
1299
1300static inline int need_resched(void)
1301{
1302	return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1303}
1304
1305/*
1306 * cond_resched() and cond_resched_lock(): latency reduction via
1307 * explicit rescheduling in places that are safe. The return
1308 * value indicates whether a reschedule was done in fact.
1309 * cond_resched_lock() will drop the spinlock before scheduling,
1310 * cond_resched_softirq() will enable bhs before scheduling.
1311 */
1312extern int cond_resched(void);
1313extern int cond_resched_lock(spinlock_t * lock);
1314extern int cond_resched_softirq(void);
1315
1316/*
1317 * Does a critical section need to be broken due to another
1318 * task waiting?:
1319 */
1320#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
1321# define need_lockbreak(lock) ((lock)->break_lock)
1322#else
1323# define need_lockbreak(lock) 0
1324#endif
1325
1326/*
1327 * Does a critical section need to be broken due to another
1328 * task waiting or preemption being signalled:
1329 */
1330static inline int lock_need_resched(spinlock_t *lock)
1331{
1332	if (need_lockbreak(lock) || need_resched())
1333		return 1;
1334	return 0;
1335}
1336
1337/* Reevaluate whether the task has signals pending delivery.
1338   This is required every time the blocked sigset_t changes.
1339   callers must hold sighand->siglock.  */
1340
1341extern FASTCALL(void recalc_sigpending_tsk(struct task_struct *t));
1342extern void recalc_sigpending(void);
1343
1344extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1345
1346/*
1347 * Wrappers for p->thread_info->cpu access. No-op on UP.
1348 */
1349#ifdef CONFIG_SMP
1350
1351static inline unsigned int task_cpu(const struct task_struct *p)
1352{
1353	return task_thread_info(p)->cpu;
1354}
1355
1356static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1357{
1358	task_thread_info(p)->cpu = cpu;
1359}
1360
1361#else
1362
1363static inline unsigned int task_cpu(const struct task_struct *p)
1364{
1365	return 0;
1366}
1367
1368static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1369{
1370}
1371
1372#endif /* CONFIG_SMP */
1373
1374#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1375extern void arch_pick_mmap_layout(struct mm_struct *mm);
1376#else
1377static inline void arch_pick_mmap_layout(struct mm_struct *mm)
1378{
1379	mm->mmap_base = TASK_UNMAPPED_BASE;
1380	mm->get_unmapped_area = arch_get_unmapped_area;
1381	mm->unmap_area = arch_unmap_area;
1382}
1383#endif
1384
1385extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
1386extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
1387
1388extern void normalize_rt_tasks(void);
1389
1390#ifdef CONFIG_PM
1391/*
1392 * Check if a process has been frozen
1393 */
1394static inline int frozen(struct task_struct *p)
1395{
1396	return p->flags & PF_FROZEN;
1397}
1398
1399/*
1400 * Check if there is a request to freeze a process
1401 */
1402static inline int freezing(struct task_struct *p)
1403{
1404	return p->flags & PF_FREEZE;
1405}
1406
1407/*
1408 * Request that a process be frozen
1409 * FIXME: SMP problem. We may not modify other process' flags!
1410 */
1411static inline void freeze(struct task_struct *p)
1412{
1413	p->flags |= PF_FREEZE;
1414}
1415
1416/*
1417 * Wake up a frozen process
1418 */
1419static inline int thaw_process(struct task_struct *p)
1420{
1421	if (frozen(p)) {
1422		p->flags &= ~PF_FROZEN;
1423		wake_up_process(p);
1424		return 1;
1425	}
1426	return 0;
1427}
1428
1429/*
1430 * freezing is complete, mark process as frozen
1431 */
1432static inline void frozen_process(struct task_struct *p)
1433{
1434	p->flags = (p->flags & ~PF_FREEZE) | PF_FROZEN;
1435}
1436
1437extern void refrigerator(void);
1438extern int freeze_processes(void);
1439extern void thaw_processes(void);
1440
1441static inline int try_to_freeze(void)
1442{
1443	if (freezing(current)) {
1444		refrigerator();
1445		return 1;
1446	} else
1447		return 0;
1448}
1449#else
1450static inline int frozen(struct task_struct *p) { return 0; }
1451static inline int freezing(struct task_struct *p) { return 0; }
1452static inline void freeze(struct task_struct *p) { BUG(); }
1453static inline int thaw_process(struct task_struct *p) { return 1; }
1454static inline void frozen_process(struct task_struct *p) { BUG(); }
1455
1456static inline void refrigerator(void) {}
1457static inline int freeze_processes(void) { BUG(); return 0; }
1458static inline void thaw_processes(void) {}
1459
1460static inline int try_to_freeze(void) { return 0; }
1461
1462#endif /* CONFIG_PM */
1463#endif /* __KERNEL__ */
1464
1465#endif
1466