sched.h revision 3e30148c3d524a9c1c63ca28261bc24c457eb07a
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
38struct exec_domain;
39
40/*
41 * cloning flags:
42 */
43#define CSIGNAL		0x000000ff	/* signal mask to be sent at exit */
44#define CLONE_VM	0x00000100	/* set if VM shared between processes */
45#define CLONE_FS	0x00000200	/* set if fs info shared between processes */
46#define CLONE_FILES	0x00000400	/* set if open files shared between processes */
47#define CLONE_SIGHAND	0x00000800	/* set if signal handlers and blocked signals shared */
48#define CLONE_PTRACE	0x00002000	/* set if we want to let tracing continue on the child too */
49#define CLONE_VFORK	0x00004000	/* set if the parent wants the child to wake it up on mm_release */
50#define CLONE_PARENT	0x00008000	/* set if we want to have the same parent as the cloner */
51#define CLONE_THREAD	0x00010000	/* Same thread group? */
52#define CLONE_NEWNS	0x00020000	/* New namespace group? */
53#define CLONE_SYSVSEM	0x00040000	/* share system V SEM_UNDO semantics */
54#define CLONE_SETTLS	0x00080000	/* create a new TLS for the child */
55#define CLONE_PARENT_SETTID	0x00100000	/* set the TID in the parent */
56#define CLONE_CHILD_CLEARTID	0x00200000	/* clear the TID in the child */
57#define CLONE_DETACHED		0x00400000	/* Unused, ignored */
58#define CLONE_UNTRACED		0x00800000	/* set if the tracing process can't force CLONE_PTRACE on this clone */
59#define CLONE_CHILD_SETTID	0x01000000	/* set the TID in the child */
60#define CLONE_STOPPED		0x02000000	/* Start in stopped state */
61
62/*
63 * List of flags we want to share for kernel threads,
64 * if only because they are not used by them anyway.
65 */
66#define CLONE_KERNEL	(CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
67
68/*
69 * These are the constant used to fake the fixed-point load-average
70 * counting. Some notes:
71 *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
72 *    a load-average precision of 10 bits integer + 11 bits fractional
73 *  - if you want to count load-averages more often, you need more
74 *    precision, or rounding will get you. With 2-second counting freq,
75 *    the EXP_n values would be 1981, 2034 and 2043 if still using only
76 *    11 bit fractions.
77 */
78extern unsigned long avenrun[];		/* Load averages */
79
80#define FSHIFT		11		/* nr of bits of precision */
81#define FIXED_1		(1<<FSHIFT)	/* 1.0 as fixed-point */
82#define LOAD_FREQ	(5*HZ)		/* 5 sec intervals */
83#define EXP_1		1884		/* 1/exp(5sec/1min) as fixed-point */
84#define EXP_5		2014		/* 1/exp(5sec/5min) */
85#define EXP_15		2037		/* 1/exp(5sec/15min) */
86
87#define CALC_LOAD(load,exp,n) \
88	load *= exp; \
89	load += n*(FIXED_1-exp); \
90	load >>= FSHIFT;
91
92extern unsigned long total_forks;
93extern int nr_threads;
94extern int last_pid;
95DECLARE_PER_CPU(unsigned long, process_counts);
96extern int nr_processes(void);
97extern unsigned long nr_running(void);
98extern unsigned long nr_uninterruptible(void);
99extern unsigned long nr_iowait(void);
100
101#include <linux/time.h>
102#include <linux/param.h>
103#include <linux/resource.h>
104#include <linux/timer.h>
105
106#include <asm/processor.h>
107
108#define TASK_RUNNING		0
109#define TASK_INTERRUPTIBLE	1
110#define TASK_UNINTERRUPTIBLE	2
111#define TASK_STOPPED		4
112#define TASK_TRACED		8
113#define EXIT_ZOMBIE		16
114#define EXIT_DEAD		32
115
116#define __set_task_state(tsk, state_value)		\
117	do { (tsk)->state = (state_value); } while (0)
118#define set_task_state(tsk, state_value)		\
119	set_mb((tsk)->state, (state_value))
120
121#define __set_current_state(state_value)			\
122	do { current->state = (state_value); } while (0)
123#define set_current_state(state_value)		\
124	set_mb(current->state, (state_value))
125
126/* Task command name length */
127#define TASK_COMM_LEN 16
128
129/*
130 * Scheduling policies
131 */
132#define SCHED_NORMAL		0
133#define SCHED_FIFO		1
134#define SCHED_RR		2
135
136struct sched_param {
137	int sched_priority;
138};
139
140#ifdef __KERNEL__
141
142#include <linux/spinlock.h>
143
144/*
145 * This serializes "schedule()" and also protects
146 * the run-queue from deletions/modifications (but
147 * _adding_ to the beginning of the run-queue has
148 * a separate lock).
149 */
150extern rwlock_t tasklist_lock;
151extern spinlock_t mmlist_lock;
152
153typedef struct task_struct task_t;
154
155extern void sched_init(void);
156extern void sched_init_smp(void);
157extern void init_idle(task_t *idle, int cpu);
158
159extern cpumask_t nohz_cpu_mask;
160
161extern void show_state(void);
162extern void show_regs(struct pt_regs *);
163
164/*
165 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
166 * task), SP is the stack pointer of the first frame that should be shown in the back
167 * trace (or NULL if the entire call-chain of the task should be shown).
168 */
169extern void show_stack(struct task_struct *task, unsigned long *sp);
170
171void io_schedule(void);
172long io_schedule_timeout(long timeout);
173
174extern void cpu_init (void);
175extern void trap_init(void);
176extern void update_process_times(int user);
177extern void scheduler_tick(void);
178
179/* Attach to any functions which should be ignored in wchan output. */
180#define __sched		__attribute__((__section__(".sched.text")))
181/* Is this address in the __sched functions? */
182extern int in_sched_functions(unsigned long addr);
183
184#define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
185extern signed long FASTCALL(schedule_timeout(signed long timeout));
186asmlinkage void schedule(void);
187
188struct namespace;
189
190/* Maximum number of active map areas.. This is a random (large) number */
191#define DEFAULT_MAX_MAP_COUNT	65536
192
193extern int sysctl_max_map_count;
194
195#include <linux/aio.h>
196
197extern unsigned long
198arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
199		       unsigned long, unsigned long);
200extern unsigned long
201arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
202			  unsigned long len, unsigned long pgoff,
203			  unsigned long flags);
204extern void arch_unmap_area(struct mm_struct *, unsigned long);
205extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
206
207#define set_mm_counter(mm, member, value) (mm)->_##member = (value)
208#define get_mm_counter(mm, member) ((mm)->_##member)
209#define add_mm_counter(mm, member, value) (mm)->_##member += (value)
210#define inc_mm_counter(mm, member) (mm)->_##member++
211#define dec_mm_counter(mm, member) (mm)->_##member--
212typedef unsigned long mm_counter_t;
213
214struct mm_struct {
215	struct vm_area_struct * mmap;		/* list of VMAs */
216	struct rb_root mm_rb;
217	struct vm_area_struct * mmap_cache;	/* last find_vma result */
218	unsigned long (*get_unmapped_area) (struct file *filp,
219				unsigned long addr, unsigned long len,
220				unsigned long pgoff, unsigned long flags);
221	void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
222        unsigned long mmap_base;		/* base of mmap area */
223        unsigned long cached_hole_size;         /* if non-zero, the largest hole below free_area_cache */
224	unsigned long free_area_cache;		/* first hole of size cached_hole_size or larger */
225	pgd_t * pgd;
226	atomic_t mm_users;			/* How many users with user space? */
227	atomic_t mm_count;			/* How many references to "struct mm_struct" (users count as 1) */
228	int map_count;				/* number of VMAs */
229	struct rw_semaphore mmap_sem;
230	spinlock_t page_table_lock;		/* Protects page tables and some counters */
231
232	struct list_head mmlist;		/* List of maybe swapped mm's.  These are globally strung
233						 * together off init_mm.mmlist, and are protected
234						 * by mmlist_lock
235						 */
236
237	unsigned long start_code, end_code, start_data, end_data;
238	unsigned long start_brk, brk, start_stack;
239	unsigned long arg_start, arg_end, env_start, env_end;
240	unsigned long total_vm, locked_vm, shared_vm;
241	unsigned long exec_vm, stack_vm, reserved_vm, def_flags, nr_ptes;
242
243	/* Special counters protected by the page_table_lock */
244	mm_counter_t _rss;
245	mm_counter_t _anon_rss;
246
247	unsigned long saved_auxv[42]; /* for /proc/PID/auxv */
248
249	unsigned dumpable:2;
250	cpumask_t cpu_vm_mask;
251
252	/* Architecture-specific MM context */
253	mm_context_t context;
254
255	/* Token based thrashing protection. */
256	unsigned long swap_token_time;
257	char recent_pagein;
258
259	/* coredumping support */
260	int core_waiters;
261	struct completion *core_startup_done, core_done;
262
263	/* aio bits */
264	rwlock_t		ioctx_list_lock;
265	struct kioctx		*ioctx_list;
266
267	struct kioctx		default_kioctx;
268
269	unsigned long hiwater_rss;	/* High-water RSS usage */
270	unsigned long hiwater_vm;	/* High-water virtual memory usage */
271};
272
273struct sighand_struct {
274	atomic_t		count;
275	struct k_sigaction	action[_NSIG];
276	spinlock_t		siglock;
277};
278
279/*
280 * NOTE! "signal_struct" does not have it's own
281 * locking, because a shared signal_struct always
282 * implies a shared sighand_struct, so locking
283 * sighand_struct is always a proper superset of
284 * the locking of signal_struct.
285 */
286struct signal_struct {
287	atomic_t		count;
288	atomic_t		live;
289
290	wait_queue_head_t	wait_chldexit;	/* for wait4() */
291
292	/* current thread group signal load-balancing target: */
293	task_t			*curr_target;
294
295	/* shared signal handling: */
296	struct sigpending	shared_pending;
297
298	/* thread group exit support */
299	int			group_exit_code;
300	/* overloaded:
301	 * - notify group_exit_task when ->count is equal to notify_count
302	 * - everyone except group_exit_task is stopped during signal delivery
303	 *   of fatal signals, group_exit_task processes the signal.
304	 */
305	struct task_struct	*group_exit_task;
306	int			notify_count;
307
308	/* thread group stop support, overloads group_exit_code too */
309	int			group_stop_count;
310	unsigned int		flags; /* see SIGNAL_* flags below */
311
312	/* POSIX.1b Interval Timers */
313	struct list_head posix_timers;
314
315	/* ITIMER_REAL timer for the process */
316	struct timer_list real_timer;
317	unsigned long it_real_value, it_real_incr;
318
319	/* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
320	cputime_t it_prof_expires, it_virt_expires;
321	cputime_t it_prof_incr, it_virt_incr;
322
323	/* job control IDs */
324	pid_t pgrp;
325	pid_t tty_old_pgrp;
326	pid_t session;
327	/* boolean value for session group leader */
328	int leader;
329
330	struct tty_struct *tty; /* NULL if no tty */
331
332	/*
333	 * Cumulative resource counters for dead threads in the group,
334	 * and for reaped dead child processes forked by this group.
335	 * Live threads maintain their own counters and add to these
336	 * in __exit_signal, except for the group leader.
337	 */
338	cputime_t utime, stime, cutime, cstime;
339	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
340	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
341
342	/*
343	 * Cumulative ns of scheduled CPU time for dead threads in the
344	 * group, not including a zombie group leader.  (This only differs
345	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
346	 * other than jiffies.)
347	 */
348	unsigned long long sched_time;
349
350	/*
351	 * We don't bother to synchronize most readers of this at all,
352	 * because there is no reader checking a limit that actually needs
353	 * to get both rlim_cur and rlim_max atomically, and either one
354	 * alone is a single word that can safely be read normally.
355	 * getrlimit/setrlimit use task_lock(current->group_leader) to
356	 * protect this instead of the siglock, because they really
357	 * have no need to disable irqs.
358	 */
359	struct rlimit rlim[RLIM_NLIMITS];
360
361	struct list_head cpu_timers[3];
362
363	/* keep the process-shared keyrings here so that they do the right
364	 * thing in threads created with CLONE_THREAD */
365#ifdef CONFIG_KEYS
366	struct key *session_keyring;	/* keyring inherited over fork */
367	struct key *process_keyring;	/* keyring private to this process */
368#endif
369};
370
371/*
372 * Bits in flags field of signal_struct.
373 */
374#define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
375#define SIGNAL_STOP_DEQUEUED	0x00000002 /* stop signal dequeued */
376#define SIGNAL_STOP_CONTINUED	0x00000004 /* SIGCONT since WCONTINUED reap */
377#define SIGNAL_GROUP_EXIT	0x00000008 /* group exit in progress */
378
379
380/*
381 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
382 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL tasks are
383 * in the range MAX_RT_PRIO..MAX_PRIO-1. Priority values
384 * are inverted: lower p->prio value means higher priority.
385 *
386 * The MAX_USER_RT_PRIO value allows the actual maximum
387 * RT priority to be separate from the value exported to
388 * user-space.  This allows kernel threads to set their
389 * priority to a value higher than any user task. Note:
390 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
391 */
392
393#define MAX_USER_RT_PRIO	100
394#define MAX_RT_PRIO		MAX_USER_RT_PRIO
395
396#define MAX_PRIO		(MAX_RT_PRIO + 40)
397
398#define rt_task(p)		(unlikely((p)->prio < MAX_RT_PRIO))
399
400/*
401 * Some day this will be a full-fledged user tracking system..
402 */
403struct user_struct {
404	atomic_t __count;	/* reference count */
405	atomic_t processes;	/* How many processes does this user have? */
406	atomic_t files;		/* How many open files does this user have? */
407	atomic_t sigpending;	/* How many pending signals does this user have? */
408	/* protected by mq_lock	*/
409	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
410	unsigned long locked_shm; /* How many pages of mlocked shm ? */
411
412#ifdef CONFIG_KEYS
413	struct key *uid_keyring;	/* UID specific keyring */
414	struct key *session_keyring;	/* UID's default session keyring */
415#endif
416
417	/* Hash table maintenance information */
418	struct list_head uidhash_list;
419	uid_t uid;
420};
421
422extern struct user_struct *find_user(uid_t);
423
424extern struct user_struct root_user;
425#define INIT_USER (&root_user)
426
427typedef struct prio_array prio_array_t;
428struct backing_dev_info;
429struct reclaim_state;
430
431#ifdef CONFIG_SCHEDSTATS
432struct sched_info {
433	/* cumulative counters */
434	unsigned long	cpu_time,	/* time spent on the cpu */
435			run_delay,	/* time spent waiting on a runqueue */
436			pcnt;		/* # of timeslices run on this cpu */
437
438	/* timestamps */
439	unsigned long	last_arrival,	/* when we last ran on a cpu */
440			last_queued;	/* when we were last queued to run */
441};
442
443extern struct file_operations proc_schedstat_operations;
444#endif
445
446enum idle_type
447{
448	SCHED_IDLE,
449	NOT_IDLE,
450	NEWLY_IDLE,
451	MAX_IDLE_TYPES
452};
453
454/*
455 * sched-domains (multiprocessor balancing) declarations:
456 */
457#ifdef CONFIG_SMP
458#define SCHED_LOAD_SCALE	128UL	/* increase resolution of load */
459
460#define SD_LOAD_BALANCE		1	/* Do load balancing on this domain. */
461#define SD_BALANCE_NEWIDLE	2	/* Balance when about to become idle */
462#define SD_BALANCE_EXEC		4	/* Balance on exec */
463#define SD_WAKE_IDLE		8	/* Wake to idle CPU on task wakeup */
464#define SD_WAKE_AFFINE		16	/* Wake task to waking CPU */
465#define SD_WAKE_BALANCE		32	/* Perform balancing at task wakeup */
466#define SD_SHARE_CPUPOWER	64	/* Domain members share cpu power */
467
468struct sched_group {
469	struct sched_group *next;	/* Must be a circular list */
470	cpumask_t cpumask;
471
472	/*
473	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
474	 * single CPU. This is read only (except for setup, hotplug CPU).
475	 */
476	unsigned long cpu_power;
477};
478
479struct sched_domain {
480	/* These fields must be setup */
481	struct sched_domain *parent;	/* top domain must be null terminated */
482	struct sched_group *groups;	/* the balancing groups of the domain */
483	cpumask_t span;			/* span of all CPUs in this domain */
484	unsigned long min_interval;	/* Minimum balance interval ms */
485	unsigned long max_interval;	/* Maximum balance interval ms */
486	unsigned int busy_factor;	/* less balancing by factor if busy */
487	unsigned int imbalance_pct;	/* No balance until over watermark */
488	unsigned long long cache_hot_time; /* Task considered cache hot (ns) */
489	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
490	unsigned int per_cpu_gain;	/* CPU % gained by adding domain cpus */
491	int flags;			/* See SD_* */
492
493	/* Runtime fields. */
494	unsigned long last_balance;	/* init to jiffies. units in jiffies */
495	unsigned int balance_interval;	/* initialise to 1. units in ms. */
496	unsigned int nr_balance_failed; /* initialise to 0 */
497
498#ifdef CONFIG_SCHEDSTATS
499	/* load_balance() stats */
500	unsigned long lb_cnt[MAX_IDLE_TYPES];
501	unsigned long lb_failed[MAX_IDLE_TYPES];
502	unsigned long lb_balanced[MAX_IDLE_TYPES];
503	unsigned long lb_imbalance[MAX_IDLE_TYPES];
504	unsigned long lb_gained[MAX_IDLE_TYPES];
505	unsigned long lb_hot_gained[MAX_IDLE_TYPES];
506	unsigned long lb_nobusyg[MAX_IDLE_TYPES];
507	unsigned long lb_nobusyq[MAX_IDLE_TYPES];
508
509	/* Active load balancing */
510	unsigned long alb_cnt;
511	unsigned long alb_failed;
512	unsigned long alb_pushed;
513
514	/* sched_balance_exec() stats */
515	unsigned long sbe_attempts;
516	unsigned long sbe_pushed;
517
518	/* try_to_wake_up() stats */
519	unsigned long ttwu_wake_remote;
520	unsigned long ttwu_move_affine;
521	unsigned long ttwu_move_balance;
522#endif
523};
524
525#ifdef ARCH_HAS_SCHED_DOMAIN
526/* Useful helpers that arch setup code may use. Defined in kernel/sched.c */
527extern cpumask_t cpu_isolated_map;
528extern void init_sched_build_groups(struct sched_group groups[],
529	                        cpumask_t span, int (*group_fn)(int cpu));
530extern void cpu_attach_domain(struct sched_domain *sd, int cpu);
531#endif /* ARCH_HAS_SCHED_DOMAIN */
532#endif /* CONFIG_SMP */
533
534
535struct io_context;			/* See blkdev.h */
536void exit_io_context(void);
537struct cpuset;
538
539#define NGROUPS_SMALL		32
540#define NGROUPS_PER_BLOCK	((int)(PAGE_SIZE / sizeof(gid_t)))
541struct group_info {
542	int ngroups;
543	atomic_t usage;
544	gid_t small_block[NGROUPS_SMALL];
545	int nblocks;
546	gid_t *blocks[0];
547};
548
549/*
550 * get_group_info() must be called with the owning task locked (via task_lock())
551 * when task != current.  The reason being that the vast majority of callers are
552 * looking at current->group_info, which can not be changed except by the
553 * current task.  Changing current->group_info requires the task lock, too.
554 */
555#define get_group_info(group_info) do { \
556	atomic_inc(&(group_info)->usage); \
557} while (0)
558
559#define put_group_info(group_info) do { \
560	if (atomic_dec_and_test(&(group_info)->usage)) \
561		groups_free(group_info); \
562} while (0)
563
564extern struct group_info *groups_alloc(int gidsetsize);
565extern void groups_free(struct group_info *group_info);
566extern int set_current_groups(struct group_info *group_info);
567extern int groups_search(struct group_info *group_info, gid_t grp);
568/* access the groups "array" with this macro */
569#define GROUP_AT(gi, i) \
570    ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
571
572
573struct audit_context;		/* See audit.c */
574struct mempolicy;
575
576struct task_struct {
577	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
578	struct thread_info *thread_info;
579	atomic_t usage;
580	unsigned long flags;	/* per process flags, defined below */
581	unsigned long ptrace;
582
583	int lock_depth;		/* BKL lock depth */
584
585	int prio, static_prio;
586	struct list_head run_list;
587	prio_array_t *array;
588
589	unsigned long sleep_avg;
590	unsigned long long timestamp, last_ran;
591	unsigned long long sched_time; /* sched_clock time spent running */
592	int activated;
593
594	unsigned long policy;
595	cpumask_t cpus_allowed;
596	unsigned int time_slice, first_time_slice;
597
598#ifdef CONFIG_SCHEDSTATS
599	struct sched_info sched_info;
600#endif
601
602	struct list_head tasks;
603	/*
604	 * ptrace_list/ptrace_children forms the list of my children
605	 * that were stolen by a ptracer.
606	 */
607	struct list_head ptrace_children;
608	struct list_head ptrace_list;
609
610	struct mm_struct *mm, *active_mm;
611
612/* task state */
613	struct linux_binfmt *binfmt;
614	long exit_state;
615	int exit_code, exit_signal;
616	int pdeath_signal;  /*  The signal sent when the parent dies  */
617	/* ??? */
618	unsigned long personality;
619	unsigned did_exec:1;
620	pid_t pid;
621	pid_t tgid;
622	/*
623	 * pointers to (original) parent process, youngest child, younger sibling,
624	 * older sibling, respectively.  (p->father can be replaced with
625	 * p->parent->pid)
626	 */
627	struct task_struct *real_parent; /* real parent process (when being debugged) */
628	struct task_struct *parent;	/* parent process */
629	/*
630	 * children/sibling forms the list of my children plus the
631	 * tasks I'm ptracing.
632	 */
633	struct list_head children;	/* list of my children */
634	struct list_head sibling;	/* linkage in my parent's children list */
635	struct task_struct *group_leader;	/* threadgroup leader */
636
637	/* PID/PID hash table linkage. */
638	struct pid pids[PIDTYPE_MAX];
639
640	struct completion *vfork_done;		/* for vfork() */
641	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
642	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
643
644	unsigned long rt_priority;
645	cputime_t utime, stime;
646	unsigned long nvcsw, nivcsw; /* context switch counts */
647	struct timespec start_time;
648/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
649	unsigned long min_flt, maj_flt;
650
651  	cputime_t it_prof_expires, it_virt_expires;
652	unsigned long long it_sched_expires;
653	struct list_head cpu_timers[3];
654
655/* process credentials */
656	uid_t uid,euid,suid,fsuid;
657	gid_t gid,egid,sgid,fsgid;
658	struct group_info *group_info;
659	kernel_cap_t   cap_effective, cap_inheritable, cap_permitted;
660	unsigned keep_capabilities:1;
661	struct user_struct *user;
662#ifdef CONFIG_KEYS
663	struct key *thread_keyring;	/* keyring private to this thread */
664	unsigned char jit_keyring;	/* default keyring to attach requested keys to */
665#endif
666	int oomkilladj; /* OOM kill score adjustment (bit shift). */
667	char comm[TASK_COMM_LEN]; /* executable name excluding path
668				     - access with [gs]et_task_comm (which lock
669				       it with task_lock())
670				     - initialized normally by flush_old_exec */
671/* file system info */
672	int link_count, total_link_count;
673/* ipc stuff */
674	struct sysv_sem sysvsem;
675/* CPU-specific state of this task */
676	struct thread_struct thread;
677/* filesystem information */
678	struct fs_struct *fs;
679/* open file information */
680	struct files_struct *files;
681/* namespace */
682	struct namespace *namespace;
683/* signal handlers */
684	struct signal_struct *signal;
685	struct sighand_struct *sighand;
686
687	sigset_t blocked, real_blocked;
688	struct sigpending pending;
689
690	unsigned long sas_ss_sp;
691	size_t sas_ss_size;
692	int (*notifier)(void *priv);
693	void *notifier_data;
694	sigset_t *notifier_mask;
695
696	void *security;
697	struct audit_context *audit_context;
698	seccomp_t seccomp;
699
700/* Thread group tracking */
701   	u32 parent_exec_id;
702   	u32 self_exec_id;
703/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
704	spinlock_t alloc_lock;
705/* Protection of proc_dentry: nesting proc_lock, dcache_lock, write_lock_irq(&tasklist_lock); */
706	spinlock_t proc_lock;
707/* context-switch lock */
708	spinlock_t switch_lock;
709
710/* journalling filesystem info */
711	void *journal_info;
712
713/* VM state */
714	struct reclaim_state *reclaim_state;
715
716	struct dentry *proc_dentry;
717	struct backing_dev_info *backing_dev_info;
718
719	struct io_context *io_context;
720
721	unsigned long ptrace_message;
722	siginfo_t *last_siginfo; /* For ptrace use.  */
723/*
724 * current io wait handle: wait queue entry to use for io waits
725 * If this thread is processing aio, this points at the waitqueue
726 * inside the currently handled kiocb. It may be NULL (i.e. default
727 * to a stack based synchronous wait) if its doing sync IO.
728 */
729	wait_queue_t *io_wait;
730/* i/o counters(bytes read/written, #syscalls */
731	u64 rchar, wchar, syscr, syscw;
732#if defined(CONFIG_BSD_PROCESS_ACCT)
733	u64 acct_rss_mem1;	/* accumulated rss usage */
734	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
735	clock_t acct_stimexpd;	/* clock_t-converted stime since last update */
736#endif
737#ifdef CONFIG_NUMA
738  	struct mempolicy *mempolicy;
739	short il_next;
740#endif
741#ifdef CONFIG_CPUSETS
742	struct cpuset *cpuset;
743	nodemask_t mems_allowed;
744	int cpuset_mems_generation;
745#endif
746};
747
748static inline pid_t process_group(struct task_struct *tsk)
749{
750	return tsk->signal->pgrp;
751}
752
753/**
754 * pid_alive - check that a task structure is not stale
755 * @p: Task structure to be checked.
756 *
757 * Test if a process is not yet dead (at most zombie state)
758 * If pid_alive fails, then pointers within the task structure
759 * can be stale and must not be dereferenced.
760 */
761static inline int pid_alive(struct task_struct *p)
762{
763	return p->pids[PIDTYPE_PID].nr != 0;
764}
765
766extern void free_task(struct task_struct *tsk);
767extern void __put_task_struct(struct task_struct *tsk);
768#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
769#define put_task_struct(tsk) \
770do { if (atomic_dec_and_test(&(tsk)->usage)) __put_task_struct(tsk); } while(0)
771
772/*
773 * Per process flags
774 */
775#define PF_ALIGNWARN	0x00000001	/* Print alignment warning msgs */
776					/* Not implemented yet, only for 486*/
777#define PF_STARTING	0x00000002	/* being created */
778#define PF_EXITING	0x00000004	/* getting shut down */
779#define PF_DEAD		0x00000008	/* Dead */
780#define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
781#define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
782#define PF_DUMPCORE	0x00000200	/* dumped core */
783#define PF_SIGNALED	0x00000400	/* killed by a signal */
784#define PF_MEMALLOC	0x00000800	/* Allocating memory */
785#define PF_FLUSHER	0x00001000	/* responsible for disk writeback */
786#define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
787#define PF_FREEZE	0x00004000	/* this task is being frozen for suspend now */
788#define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
789#define PF_FROZEN	0x00010000	/* frozen for system suspend */
790#define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
791#define PF_KSWAPD	0x00040000	/* I am kswapd */
792#define PF_SWAPOFF	0x00080000	/* I am in swapoff */
793#define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
794#define PF_SYNCWRITE	0x00200000	/* I am doing a sync write */
795#define PF_BORROWED_MM	0x00400000	/* I am a kthread doing use_mm */
796#define PF_RANDOMIZE	0x00800000	/* randomize virtual address space */
797
798/*
799 * Only the _current_ task can read/write to tsk->flags, but other
800 * tasks can access tsk->flags in readonly mode for example
801 * with tsk_used_math (like during threaded core dumping).
802 * There is however an exception to this rule during ptrace
803 * or during fork: the ptracer task is allowed to write to the
804 * child->flags of its traced child (same goes for fork, the parent
805 * can write to the child->flags), because we're guaranteed the
806 * child is not running and in turn not changing child->flags
807 * at the same time the parent does it.
808 */
809#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
810#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
811#define clear_used_math() clear_stopped_child_used_math(current)
812#define set_used_math() set_stopped_child_used_math(current)
813#define conditional_stopped_child_used_math(condition, child) \
814	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
815#define conditional_used_math(condition) \
816	conditional_stopped_child_used_math(condition, current)
817#define copy_to_stopped_child_used_math(child) \
818	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
819/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
820#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
821#define used_math() tsk_used_math(current)
822
823#ifdef CONFIG_SMP
824extern int set_cpus_allowed(task_t *p, cpumask_t new_mask);
825#else
826static inline int set_cpus_allowed(task_t *p, cpumask_t new_mask)
827{
828	if (!cpus_intersects(new_mask, cpu_online_map))
829		return -EINVAL;
830	return 0;
831}
832#endif
833
834extern unsigned long long sched_clock(void);
835extern unsigned long long current_sched_time(const task_t *current_task);
836
837/* sched_exec is called by processes performing an exec */
838#ifdef CONFIG_SMP
839extern void sched_exec(void);
840#else
841#define sched_exec()   {}
842#endif
843
844#ifdef CONFIG_HOTPLUG_CPU
845extern void idle_task_exit(void);
846#else
847static inline void idle_task_exit(void) {}
848#endif
849
850extern void sched_idle_next(void);
851extern void set_user_nice(task_t *p, long nice);
852extern int task_prio(const task_t *p);
853extern int task_nice(const task_t *p);
854extern int can_nice(const task_t *p, const int nice);
855extern int task_curr(const task_t *p);
856extern int idle_cpu(int cpu);
857extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
858extern task_t *idle_task(int cpu);
859
860void yield(void);
861
862/*
863 * The default (Linux) execution domain.
864 */
865extern struct exec_domain	default_exec_domain;
866
867union thread_union {
868	struct thread_info thread_info;
869	unsigned long stack[THREAD_SIZE/sizeof(long)];
870};
871
872#ifndef __HAVE_ARCH_KSTACK_END
873static inline int kstack_end(void *addr)
874{
875	/* Reliable end of stack detection:
876	 * Some APM bios versions misalign the stack
877	 */
878	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
879}
880#endif
881
882extern union thread_union init_thread_union;
883extern struct task_struct init_task;
884
885extern struct   mm_struct init_mm;
886
887#define find_task_by_pid(nr)	find_task_by_pid_type(PIDTYPE_PID, nr)
888extern struct task_struct *find_task_by_pid_type(int type, int pid);
889extern void set_special_pids(pid_t session, pid_t pgrp);
890extern void __set_special_pids(pid_t session, pid_t pgrp);
891
892/* per-UID process charging. */
893extern struct user_struct * alloc_uid(uid_t);
894static inline struct user_struct *get_uid(struct user_struct *u)
895{
896	atomic_inc(&u->__count);
897	return u;
898}
899extern void free_uid(struct user_struct *);
900extern void switch_uid(struct user_struct *);
901
902#include <asm/current.h>
903
904extern void do_timer(struct pt_regs *);
905
906extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state));
907extern int FASTCALL(wake_up_process(struct task_struct * tsk));
908extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
909						unsigned long clone_flags));
910#ifdef CONFIG_SMP
911 extern void kick_process(struct task_struct *tsk);
912#else
913 static inline void kick_process(struct task_struct *tsk) { }
914#endif
915extern void FASTCALL(sched_fork(task_t * p));
916extern void FASTCALL(sched_exit(task_t * p));
917
918extern int in_group_p(gid_t);
919extern int in_egroup_p(gid_t);
920
921extern void proc_caches_init(void);
922extern void flush_signals(struct task_struct *);
923extern void flush_signal_handlers(struct task_struct *, int force_default);
924extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
925
926static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
927{
928	unsigned long flags;
929	int ret;
930
931	spin_lock_irqsave(&tsk->sighand->siglock, flags);
932	ret = dequeue_signal(tsk, mask, info);
933	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
934
935	return ret;
936}
937
938extern void block_all_signals(int (*notifier)(void *priv), void *priv,
939			      sigset_t *mask);
940extern void unblock_all_signals(void);
941extern void release_task(struct task_struct * p);
942extern int send_sig_info(int, struct siginfo *, struct task_struct *);
943extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
944extern int force_sigsegv(int, struct task_struct *);
945extern int force_sig_info(int, struct siginfo *, struct task_struct *);
946extern int __kill_pg_info(int sig, struct siginfo *info, pid_t pgrp);
947extern int kill_pg_info(int, struct siginfo *, pid_t);
948extern int kill_proc_info(int, struct siginfo *, pid_t);
949extern void do_notify_parent(struct task_struct *, int);
950extern void force_sig(int, struct task_struct *);
951extern void force_sig_specific(int, struct task_struct *);
952extern int send_sig(int, struct task_struct *, int);
953extern void zap_other_threads(struct task_struct *p);
954extern int kill_pg(pid_t, int, int);
955extern int kill_sl(pid_t, int, int);
956extern int kill_proc(pid_t, int, int);
957extern struct sigqueue *sigqueue_alloc(void);
958extern void sigqueue_free(struct sigqueue *);
959extern int send_sigqueue(int, struct sigqueue *,  struct task_struct *);
960extern int send_group_sigqueue(int, struct sigqueue *,  struct task_struct *);
961extern int do_sigaction(int, const struct k_sigaction *, struct k_sigaction *);
962extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
963
964/* These can be the second arg to send_sig_info/send_group_sig_info.  */
965#define SEND_SIG_NOINFO ((struct siginfo *) 0)
966#define SEND_SIG_PRIV	((struct siginfo *) 1)
967#define SEND_SIG_FORCED	((struct siginfo *) 2)
968
969/* True if we are on the alternate signal stack.  */
970
971static inline int on_sig_stack(unsigned long sp)
972{
973	return (sp - current->sas_ss_sp < current->sas_ss_size);
974}
975
976static inline int sas_ss_flags(unsigned long sp)
977{
978	return (current->sas_ss_size == 0 ? SS_DISABLE
979		: on_sig_stack(sp) ? SS_ONSTACK : 0);
980}
981
982
983#ifdef CONFIG_SECURITY
984/* code is in security.c */
985extern int capable(int cap);
986#else
987static inline int capable(int cap)
988{
989	if (cap_raised(current->cap_effective, cap)) {
990		current->flags |= PF_SUPERPRIV;
991		return 1;
992	}
993	return 0;
994}
995#endif
996
997/*
998 * Routines for handling mm_structs
999 */
1000extern struct mm_struct * mm_alloc(void);
1001
1002/* mmdrop drops the mm and the page tables */
1003extern void FASTCALL(__mmdrop(struct mm_struct *));
1004static inline void mmdrop(struct mm_struct * mm)
1005{
1006	if (atomic_dec_and_test(&mm->mm_count))
1007		__mmdrop(mm);
1008}
1009
1010/* mmput gets rid of the mappings and all user-space */
1011extern void mmput(struct mm_struct *);
1012/* Grab a reference to a task's mm, if it is not already going away */
1013extern struct mm_struct *get_task_mm(struct task_struct *task);
1014/* Remove the current tasks stale references to the old mm_struct */
1015extern void mm_release(struct task_struct *, struct mm_struct *);
1016
1017extern int  copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1018extern void flush_thread(void);
1019extern void exit_thread(void);
1020
1021extern void exit_files(struct task_struct *);
1022extern void exit_signal(struct task_struct *);
1023extern void __exit_signal(struct task_struct *);
1024extern void exit_sighand(struct task_struct *);
1025extern void __exit_sighand(struct task_struct *);
1026extern void exit_itimers(struct signal_struct *);
1027
1028extern NORET_TYPE void do_group_exit(int);
1029
1030extern void daemonize(const char *, ...);
1031extern int allow_signal(int);
1032extern int disallow_signal(int);
1033extern task_t *child_reaper;
1034
1035extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1036extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1037task_t *fork_idle(int);
1038
1039extern void set_task_comm(struct task_struct *tsk, char *from);
1040extern void get_task_comm(char *to, struct task_struct *tsk);
1041
1042#ifdef CONFIG_SMP
1043extern void wait_task_inactive(task_t * p);
1044#else
1045#define wait_task_inactive(p)	do { } while (0)
1046#endif
1047
1048#define remove_parent(p)	list_del_init(&(p)->sibling)
1049#define add_parent(p, parent)	list_add_tail(&(p)->sibling,&(parent)->children)
1050
1051#define REMOVE_LINKS(p) do {					\
1052	if (thread_group_leader(p))				\
1053		list_del_init(&(p)->tasks);			\
1054	remove_parent(p);					\
1055	} while (0)
1056
1057#define SET_LINKS(p) do {					\
1058	if (thread_group_leader(p))				\
1059		list_add_tail(&(p)->tasks,&init_task.tasks);	\
1060	add_parent(p, (p)->parent);				\
1061	} while (0)
1062
1063#define next_task(p)	list_entry((p)->tasks.next, struct task_struct, tasks)
1064#define prev_task(p)	list_entry((p)->tasks.prev, struct task_struct, tasks)
1065
1066#define for_each_process(p) \
1067	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1068
1069/*
1070 * Careful: do_each_thread/while_each_thread is a double loop so
1071 *          'break' will not work as expected - use goto instead.
1072 */
1073#define do_each_thread(g, t) \
1074	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1075
1076#define while_each_thread(g, t) \
1077	while ((t = next_thread(t)) != g)
1078
1079extern task_t * FASTCALL(next_thread(const task_t *p));
1080
1081#define thread_group_leader(p)	(p->pid == p->tgid)
1082
1083static inline int thread_group_empty(task_t *p)
1084{
1085	return list_empty(&p->pids[PIDTYPE_TGID].pid_list);
1086}
1087
1088#define delay_group_leader(p) \
1089		(thread_group_leader(p) && !thread_group_empty(p))
1090
1091extern void unhash_process(struct task_struct *p);
1092
1093/*
1094 * Protects ->fs, ->files, ->mm, ->ptrace, ->group_info, ->comm, keyring
1095 * subscriptions and synchronises with wait4().  Also used in procfs.
1096 *
1097 * Nests both inside and outside of read_lock(&tasklist_lock).
1098 * It must not be nested with write_lock_irq(&tasklist_lock),
1099 * neither inside nor outside.
1100 */
1101static inline void task_lock(struct task_struct *p)
1102{
1103	spin_lock(&p->alloc_lock);
1104}
1105
1106static inline void task_unlock(struct task_struct *p)
1107{
1108	spin_unlock(&p->alloc_lock);
1109}
1110
1111/* set thread flags in other task's structures
1112 * - see asm/thread_info.h for TIF_xxxx flags available
1113 */
1114static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1115{
1116	set_ti_thread_flag(tsk->thread_info,flag);
1117}
1118
1119static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1120{
1121	clear_ti_thread_flag(tsk->thread_info,flag);
1122}
1123
1124static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1125{
1126	return test_and_set_ti_thread_flag(tsk->thread_info,flag);
1127}
1128
1129static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1130{
1131	return test_and_clear_ti_thread_flag(tsk->thread_info,flag);
1132}
1133
1134static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1135{
1136	return test_ti_thread_flag(tsk->thread_info,flag);
1137}
1138
1139static inline void set_tsk_need_resched(struct task_struct *tsk)
1140{
1141	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1142}
1143
1144static inline void clear_tsk_need_resched(struct task_struct *tsk)
1145{
1146	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1147}
1148
1149static inline int signal_pending(struct task_struct *p)
1150{
1151	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1152}
1153
1154static inline int need_resched(void)
1155{
1156	return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1157}
1158
1159/*
1160 * cond_resched() and cond_resched_lock(): latency reduction via
1161 * explicit rescheduling in places that are safe. The return
1162 * value indicates whether a reschedule was done in fact.
1163 * cond_resched_lock() will drop the spinlock before scheduling,
1164 * cond_resched_softirq() will enable bhs before scheduling.
1165 */
1166extern int cond_resched(void);
1167extern int cond_resched_lock(spinlock_t * lock);
1168extern int cond_resched_softirq(void);
1169
1170/*
1171 * Does a critical section need to be broken due to another
1172 * task waiting?:
1173 */
1174#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
1175# define need_lockbreak(lock) ((lock)->break_lock)
1176#else
1177# define need_lockbreak(lock) 0
1178#endif
1179
1180/*
1181 * Does a critical section need to be broken due to another
1182 * task waiting or preemption being signalled:
1183 */
1184static inline int lock_need_resched(spinlock_t *lock)
1185{
1186	if (need_lockbreak(lock) || need_resched())
1187		return 1;
1188	return 0;
1189}
1190
1191/* Reevaluate whether the task has signals pending delivery.
1192   This is required every time the blocked sigset_t changes.
1193   callers must hold sighand->siglock.  */
1194
1195extern FASTCALL(void recalc_sigpending_tsk(struct task_struct *t));
1196extern void recalc_sigpending(void);
1197
1198extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1199
1200/*
1201 * Wrappers for p->thread_info->cpu access. No-op on UP.
1202 */
1203#ifdef CONFIG_SMP
1204
1205static inline unsigned int task_cpu(const struct task_struct *p)
1206{
1207	return p->thread_info->cpu;
1208}
1209
1210static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1211{
1212	p->thread_info->cpu = cpu;
1213}
1214
1215#else
1216
1217static inline unsigned int task_cpu(const struct task_struct *p)
1218{
1219	return 0;
1220}
1221
1222static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1223{
1224}
1225
1226#endif /* CONFIG_SMP */
1227
1228#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1229extern void arch_pick_mmap_layout(struct mm_struct *mm);
1230#else
1231static inline void arch_pick_mmap_layout(struct mm_struct *mm)
1232{
1233	mm->mmap_base = TASK_UNMAPPED_BASE;
1234	mm->get_unmapped_area = arch_get_unmapped_area;
1235	mm->unmap_area = arch_unmap_area;
1236}
1237#endif
1238
1239extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
1240extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
1241
1242#ifdef CONFIG_MAGIC_SYSRQ
1243
1244extern void normalize_rt_tasks(void);
1245
1246#endif
1247
1248/* try_to_freeze
1249 *
1250 * Checks whether we need to enter the refrigerator
1251 * and returns 1 if we did so.
1252 */
1253#ifdef CONFIG_PM
1254extern void refrigerator(unsigned long);
1255extern int freeze_processes(void);
1256extern void thaw_processes(void);
1257
1258static inline int try_to_freeze(unsigned long refrigerator_flags)
1259{
1260	if (unlikely(current->flags & PF_FREEZE)) {
1261		refrigerator(refrigerator_flags);
1262		return 1;
1263	} else
1264		return 0;
1265}
1266#else
1267static inline void refrigerator(unsigned long flag) {}
1268static inline int freeze_processes(void) { BUG(); return 0; }
1269static inline void thaw_processes(void) {}
1270
1271static inline int try_to_freeze(unsigned long refrigerator_flags)
1272{
1273	return 0;
1274}
1275#endif /* CONFIG_PM */
1276#endif /* __KERNEL__ */
1277
1278#endif
1279