xref: /linux/include/linux/sched.h (revision 5e8d780d745c1619aba81fe7166c5a4b5cad2b84)
1 #ifndef _LINUX_SCHED_H
2 #define _LINUX_SCHED_H
3 
4 #include <linux/auxvec.h>	/* For AT_VECTOR_SIZE */
5 
6 /*
7  * cloning flags:
8  */
9 #define CSIGNAL		0x000000ff	/* signal mask to be sent at exit */
10 #define CLONE_VM	0x00000100	/* set if VM shared between processes */
11 #define CLONE_FS	0x00000200	/* set if fs info shared between processes */
12 #define CLONE_FILES	0x00000400	/* set if open files shared between processes */
13 #define CLONE_SIGHAND	0x00000800	/* set if signal handlers and blocked signals shared */
14 #define CLONE_PTRACE	0x00002000	/* set if we want to let tracing continue on the child too */
15 #define CLONE_VFORK	0x00004000	/* set if the parent wants the child to wake it up on mm_release */
16 #define CLONE_PARENT	0x00008000	/* set if we want to have the same parent as the cloner */
17 #define CLONE_THREAD	0x00010000	/* Same thread group? */
18 #define CLONE_NEWNS	0x00020000	/* New namespace group? */
19 #define CLONE_SYSVSEM	0x00040000	/* share system V SEM_UNDO semantics */
20 #define CLONE_SETTLS	0x00080000	/* create a new TLS for the child */
21 #define CLONE_PARENT_SETTID	0x00100000	/* set the TID in the parent */
22 #define CLONE_CHILD_CLEARTID	0x00200000	/* clear the TID in the child */
23 #define CLONE_DETACHED		0x00400000	/* Unused, ignored */
24 #define CLONE_UNTRACED		0x00800000	/* set if the tracing process can't force CLONE_PTRACE on this clone */
25 #define CLONE_CHILD_SETTID	0x01000000	/* set the TID in the child */
26 #define CLONE_STOPPED		0x02000000	/* Start in stopped state */
27 
28 /*
29  * Scheduling policies
30  */
31 #define SCHED_NORMAL		0
32 #define SCHED_FIFO		1
33 #define SCHED_RR		2
34 #define SCHED_BATCH		3
35 
36 #ifdef __KERNEL__
37 
38 struct sched_param {
39 	int sched_priority;
40 };
41 
42 #include <asm/param.h>	/* for HZ */
43 
44 #include <linux/capability.h>
45 #include <linux/threads.h>
46 #include <linux/kernel.h>
47 #include <linux/types.h>
48 #include <linux/timex.h>
49 #include <linux/jiffies.h>
50 #include <linux/rbtree.h>
51 #include <linux/thread_info.h>
52 #include <linux/cpumask.h>
53 #include <linux/errno.h>
54 #include <linux/nodemask.h>
55 
56 #include <asm/system.h>
57 #include <asm/semaphore.h>
58 #include <asm/page.h>
59 #include <asm/ptrace.h>
60 #include <asm/mmu.h>
61 #include <asm/cputime.h>
62 
63 #include <linux/smp.h>
64 #include <linux/sem.h>
65 #include <linux/signal.h>
66 #include <linux/securebits.h>
67 #include <linux/fs_struct.h>
68 #include <linux/compiler.h>
69 #include <linux/completion.h>
70 #include <linux/pid.h>
71 #include <linux/percpu.h>
72 #include <linux/topology.h>
73 #include <linux/seccomp.h>
74 #include <linux/rcupdate.h>
75 #include <linux/futex.h>
76 #include <linux/rtmutex.h>
77 
78 #include <linux/time.h>
79 #include <linux/param.h>
80 #include <linux/resource.h>
81 #include <linux/timer.h>
82 #include <linux/hrtimer.h>
83 
84 #include <asm/processor.h>
85 
86 struct exec_domain;
87 struct futex_pi_state;
88 
89 /*
90  * List of flags we want to share for kernel threads,
91  * if only because they are not used by them anyway.
92  */
93 #define CLONE_KERNEL	(CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
94 
95 /*
96  * These are the constant used to fake the fixed-point load-average
97  * counting. Some notes:
98  *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
99  *    a load-average precision of 10 bits integer + 11 bits fractional
100  *  - if you want to count load-averages more often, you need more
101  *    precision, or rounding will get you. With 2-second counting freq,
102  *    the EXP_n values would be 1981, 2034 and 2043 if still using only
103  *    11 bit fractions.
104  */
105 extern unsigned long avenrun[];		/* Load averages */
106 
107 #define FSHIFT		11		/* nr of bits of precision */
108 #define FIXED_1		(1<<FSHIFT)	/* 1.0 as fixed-point */
109 #define LOAD_FREQ	(5*HZ)		/* 5 sec intervals */
110 #define EXP_1		1884		/* 1/exp(5sec/1min) as fixed-point */
111 #define EXP_5		2014		/* 1/exp(5sec/5min) */
112 #define EXP_15		2037		/* 1/exp(5sec/15min) */
113 
114 #define CALC_LOAD(load,exp,n) \
115 	load *= exp; \
116 	load += n*(FIXED_1-exp); \
117 	load >>= FSHIFT;
118 
119 extern unsigned long total_forks;
120 extern int nr_threads;
121 extern int last_pid;
122 DECLARE_PER_CPU(unsigned long, process_counts);
123 extern int nr_processes(void);
124 extern unsigned long nr_running(void);
125 extern unsigned long nr_uninterruptible(void);
126 extern unsigned long nr_active(void);
127 extern unsigned long nr_iowait(void);
128 extern unsigned long weighted_cpuload(const int cpu);
129 
130 
131 /*
132  * Task state bitmask. NOTE! These bits are also
133  * encoded in fs/proc/array.c: get_task_state().
134  *
135  * We have two separate sets of flags: task->state
136  * is about runnability, while task->exit_state are
137  * about the task exiting. Confusing, but this way
138  * modifying one set can't modify the other one by
139  * mistake.
140  */
141 #define TASK_RUNNING		0
142 #define TASK_INTERRUPTIBLE	1
143 #define TASK_UNINTERRUPTIBLE	2
144 #define TASK_STOPPED		4
145 #define TASK_TRACED		8
146 /* in tsk->exit_state */
147 #define EXIT_ZOMBIE		16
148 #define EXIT_DEAD		32
149 /* in tsk->state again */
150 #define TASK_NONINTERACTIVE	64
151 
152 #define __set_task_state(tsk, state_value)		\
153 	do { (tsk)->state = (state_value); } while (0)
154 #define set_task_state(tsk, state_value)		\
155 	set_mb((tsk)->state, (state_value))
156 
157 /*
158  * set_current_state() includes a barrier so that the write of current->state
159  * is correctly serialised wrt the caller's subsequent test of whether to
160  * actually sleep:
161  *
162  *	set_current_state(TASK_UNINTERRUPTIBLE);
163  *	if (do_i_need_to_sleep())
164  *		schedule();
165  *
166  * If the caller does not need such serialisation then use __set_current_state()
167  */
168 #define __set_current_state(state_value)			\
169 	do { current->state = (state_value); } while (0)
170 #define set_current_state(state_value)		\
171 	set_mb(current->state, (state_value))
172 
173 /* Task command name length */
174 #define TASK_COMM_LEN 16
175 
176 #include <linux/spinlock.h>
177 
178 /*
179  * This serializes "schedule()" and also protects
180  * the run-queue from deletions/modifications (but
181  * _adding_ to the beginning of the run-queue has
182  * a separate lock).
183  */
184 extern rwlock_t tasklist_lock;
185 extern spinlock_t mmlist_lock;
186 
187 typedef struct task_struct task_t;
188 
189 extern void sched_init(void);
190 extern void sched_init_smp(void);
191 extern void init_idle(task_t *idle, int cpu);
192 
193 extern cpumask_t nohz_cpu_mask;
194 
195 extern void show_state(void);
196 extern void show_regs(struct pt_regs *);
197 
198 /*
199  * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
200  * task), SP is the stack pointer of the first frame that should be shown in the back
201  * trace (or NULL if the entire call-chain of the task should be shown).
202  */
203 extern void show_stack(struct task_struct *task, unsigned long *sp);
204 
205 void io_schedule(void);
206 long io_schedule_timeout(long timeout);
207 
208 extern void cpu_init (void);
209 extern void trap_init(void);
210 extern void update_process_times(int user);
211 extern void scheduler_tick(void);
212 
213 #ifdef CONFIG_DETECT_SOFTLOCKUP
214 extern void softlockup_tick(void);
215 extern void spawn_softlockup_task(void);
216 extern void touch_softlockup_watchdog(void);
217 #else
218 static inline void softlockup_tick(void)
219 {
220 }
221 static inline void spawn_softlockup_task(void)
222 {
223 }
224 static inline void touch_softlockup_watchdog(void)
225 {
226 }
227 #endif
228 
229 
230 /* Attach to any functions which should be ignored in wchan output. */
231 #define __sched		__attribute__((__section__(".sched.text")))
232 /* Is this address in the __sched functions? */
233 extern int in_sched_functions(unsigned long addr);
234 
235 #define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
236 extern signed long FASTCALL(schedule_timeout(signed long timeout));
237 extern signed long schedule_timeout_interruptible(signed long timeout);
238 extern signed long schedule_timeout_uninterruptible(signed long timeout);
239 asmlinkage void schedule(void);
240 
241 struct namespace;
242 
243 /* Maximum number of active map areas.. This is a random (large) number */
244 #define DEFAULT_MAX_MAP_COUNT	65536
245 
246 extern int sysctl_max_map_count;
247 
248 #include <linux/aio.h>
249 
250 extern unsigned long
251 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
252 		       unsigned long, unsigned long);
253 extern unsigned long
254 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
255 			  unsigned long len, unsigned long pgoff,
256 			  unsigned long flags);
257 extern void arch_unmap_area(struct mm_struct *, unsigned long);
258 extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
259 
260 #if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
261 /*
262  * The mm counters are not protected by its page_table_lock,
263  * so must be incremented atomically.
264  */
265 #define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
266 #define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
267 #define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
268 #define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
269 #define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
270 typedef atomic_long_t mm_counter_t;
271 
272 #else  /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
273 /*
274  * The mm counters are protected by its page_table_lock,
275  * so can be incremented directly.
276  */
277 #define set_mm_counter(mm, member, value) (mm)->_##member = (value)
278 #define get_mm_counter(mm, member) ((mm)->_##member)
279 #define add_mm_counter(mm, member, value) (mm)->_##member += (value)
280 #define inc_mm_counter(mm, member) (mm)->_##member++
281 #define dec_mm_counter(mm, member) (mm)->_##member--
282 typedef unsigned long mm_counter_t;
283 
284 #endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
285 
286 #define get_mm_rss(mm)					\
287 	(get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
288 #define update_hiwater_rss(mm)	do {			\
289 	unsigned long _rss = get_mm_rss(mm);		\
290 	if ((mm)->hiwater_rss < _rss)			\
291 		(mm)->hiwater_rss = _rss;		\
292 } while (0)
293 #define update_hiwater_vm(mm)	do {			\
294 	if ((mm)->hiwater_vm < (mm)->total_vm)		\
295 		(mm)->hiwater_vm = (mm)->total_vm;	\
296 } while (0)
297 
298 struct mm_struct {
299 	struct vm_area_struct * mmap;		/* list of VMAs */
300 	struct rb_root mm_rb;
301 	struct vm_area_struct * mmap_cache;	/* last find_vma result */
302 	unsigned long (*get_unmapped_area) (struct file *filp,
303 				unsigned long addr, unsigned long len,
304 				unsigned long pgoff, unsigned long flags);
305 	void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
306 	unsigned long mmap_base;		/* base of mmap area */
307 	unsigned long task_size;		/* size of task vm space */
308 	unsigned long cached_hole_size;         /* if non-zero, the largest hole below free_area_cache */
309 	unsigned long free_area_cache;		/* first hole of size cached_hole_size or larger */
310 	pgd_t * pgd;
311 	atomic_t mm_users;			/* How many users with user space? */
312 	atomic_t mm_count;			/* How many references to "struct mm_struct" (users count as 1) */
313 	int map_count;				/* number of VMAs */
314 	struct rw_semaphore mmap_sem;
315 	spinlock_t page_table_lock;		/* Protects page tables and some counters */
316 
317 	struct list_head mmlist;		/* List of maybe swapped mm's.  These are globally strung
318 						 * together off init_mm.mmlist, and are protected
319 						 * by mmlist_lock
320 						 */
321 
322 	/* Special counters, in some configurations protected by the
323 	 * page_table_lock, in other configurations by being atomic.
324 	 */
325 	mm_counter_t _file_rss;
326 	mm_counter_t _anon_rss;
327 
328 	unsigned long hiwater_rss;	/* High-watermark of RSS usage */
329 	unsigned long hiwater_vm;	/* High-water virtual memory usage */
330 
331 	unsigned long total_vm, locked_vm, shared_vm, exec_vm;
332 	unsigned long stack_vm, reserved_vm, def_flags, nr_ptes;
333 	unsigned long start_code, end_code, start_data, end_data;
334 	unsigned long start_brk, brk, start_stack;
335 	unsigned long arg_start, arg_end, env_start, env_end;
336 
337 	unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
338 
339 	unsigned dumpable:2;
340 	cpumask_t cpu_vm_mask;
341 
342 	/* Architecture-specific MM context */
343 	mm_context_t context;
344 
345 	/* Token based thrashing protection. */
346 	unsigned long swap_token_time;
347 	char recent_pagein;
348 
349 	/* coredumping support */
350 	int core_waiters;
351 	struct completion *core_startup_done, core_done;
352 
353 	/* aio bits */
354 	rwlock_t		ioctx_list_lock;
355 	struct kioctx		*ioctx_list;
356 };
357 
358 struct sighand_struct {
359 	atomic_t		count;
360 	struct k_sigaction	action[_NSIG];
361 	spinlock_t		siglock;
362 };
363 
364 struct pacct_struct {
365 	int			ac_flag;
366 	long			ac_exitcode;
367 	unsigned long		ac_mem;
368 	cputime_t		ac_utime, ac_stime;
369 	unsigned long		ac_minflt, ac_majflt;
370 };
371 
372 /*
373  * NOTE! "signal_struct" does not have it's own
374  * locking, because a shared signal_struct always
375  * implies a shared sighand_struct, so locking
376  * sighand_struct is always a proper superset of
377  * the locking of signal_struct.
378  */
379 struct signal_struct {
380 	atomic_t		count;
381 	atomic_t		live;
382 
383 	wait_queue_head_t	wait_chldexit;	/* for wait4() */
384 
385 	/* current thread group signal load-balancing target: */
386 	task_t			*curr_target;
387 
388 	/* shared signal handling: */
389 	struct sigpending	shared_pending;
390 
391 	/* thread group exit support */
392 	int			group_exit_code;
393 	/* overloaded:
394 	 * - notify group_exit_task when ->count is equal to notify_count
395 	 * - everyone except group_exit_task is stopped during signal delivery
396 	 *   of fatal signals, group_exit_task processes the signal.
397 	 */
398 	struct task_struct	*group_exit_task;
399 	int			notify_count;
400 
401 	/* thread group stop support, overloads group_exit_code too */
402 	int			group_stop_count;
403 	unsigned int		flags; /* see SIGNAL_* flags below */
404 
405 	/* POSIX.1b Interval Timers */
406 	struct list_head posix_timers;
407 
408 	/* ITIMER_REAL timer for the process */
409 	struct hrtimer real_timer;
410 	struct task_struct *tsk;
411 	ktime_t it_real_incr;
412 
413 	/* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
414 	cputime_t it_prof_expires, it_virt_expires;
415 	cputime_t it_prof_incr, it_virt_incr;
416 
417 	/* job control IDs */
418 	pid_t pgrp;
419 	pid_t tty_old_pgrp;
420 	pid_t session;
421 	/* boolean value for session group leader */
422 	int leader;
423 
424 	struct tty_struct *tty; /* NULL if no tty */
425 
426 	/*
427 	 * Cumulative resource counters for dead threads in the group,
428 	 * and for reaped dead child processes forked by this group.
429 	 * Live threads maintain their own counters and add to these
430 	 * in __exit_signal, except for the group leader.
431 	 */
432 	cputime_t utime, stime, cutime, cstime;
433 	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
434 	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
435 
436 	/*
437 	 * Cumulative ns of scheduled CPU time for dead threads in the
438 	 * group, not including a zombie group leader.  (This only differs
439 	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
440 	 * other than jiffies.)
441 	 */
442 	unsigned long long sched_time;
443 
444 	/*
445 	 * We don't bother to synchronize most readers of this at all,
446 	 * because there is no reader checking a limit that actually needs
447 	 * to get both rlim_cur and rlim_max atomically, and either one
448 	 * alone is a single word that can safely be read normally.
449 	 * getrlimit/setrlimit use task_lock(current->group_leader) to
450 	 * protect this instead of the siglock, because they really
451 	 * have no need to disable irqs.
452 	 */
453 	struct rlimit rlim[RLIM_NLIMITS];
454 
455 	struct list_head cpu_timers[3];
456 
457 	/* keep the process-shared keyrings here so that they do the right
458 	 * thing in threads created with CLONE_THREAD */
459 #ifdef CONFIG_KEYS
460 	struct key *session_keyring;	/* keyring inherited over fork */
461 	struct key *process_keyring;	/* keyring private to this process */
462 #endif
463 #ifdef CONFIG_BSD_PROCESS_ACCT
464 	struct pacct_struct pacct;	/* per-process accounting information */
465 #endif
466 };
467 
468 /* Context switch must be unlocked if interrupts are to be enabled */
469 #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
470 # define __ARCH_WANT_UNLOCKED_CTXSW
471 #endif
472 
473 /*
474  * Bits in flags field of signal_struct.
475  */
476 #define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
477 #define SIGNAL_STOP_DEQUEUED	0x00000002 /* stop signal dequeued */
478 #define SIGNAL_STOP_CONTINUED	0x00000004 /* SIGCONT since WCONTINUED reap */
479 #define SIGNAL_GROUP_EXIT	0x00000008 /* group exit in progress */
480 
481 
482 /*
483  * Priority of a process goes from 0..MAX_PRIO-1, valid RT
484  * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
485  * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
486  * values are inverted: lower p->prio value means higher priority.
487  *
488  * The MAX_USER_RT_PRIO value allows the actual maximum
489  * RT priority to be separate from the value exported to
490  * user-space.  This allows kernel threads to set their
491  * priority to a value higher than any user task. Note:
492  * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
493  */
494 
495 #define MAX_USER_RT_PRIO	100
496 #define MAX_RT_PRIO		MAX_USER_RT_PRIO
497 
498 #define MAX_PRIO		(MAX_RT_PRIO + 40)
499 
500 #define rt_prio(prio)		unlikely((prio) < MAX_RT_PRIO)
501 #define rt_task(p)		rt_prio((p)->prio)
502 #define batch_task(p)		(unlikely((p)->policy == SCHED_BATCH))
503 #define has_rt_policy(p) \
504 	unlikely((p)->policy != SCHED_NORMAL && (p)->policy != SCHED_BATCH)
505 
506 /*
507  * Some day this will be a full-fledged user tracking system..
508  */
509 struct user_struct {
510 	atomic_t __count;	/* reference count */
511 	atomic_t processes;	/* How many processes does this user have? */
512 	atomic_t files;		/* How many open files does this user have? */
513 	atomic_t sigpending;	/* How many pending signals does this user have? */
514 #ifdef CONFIG_INOTIFY_USER
515 	atomic_t inotify_watches; /* How many inotify watches does this user have? */
516 	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
517 #endif
518 	/* protected by mq_lock	*/
519 	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
520 	unsigned long locked_shm; /* How many pages of mlocked shm ? */
521 
522 #ifdef CONFIG_KEYS
523 	struct key *uid_keyring;	/* UID specific keyring */
524 	struct key *session_keyring;	/* UID's default session keyring */
525 #endif
526 
527 	/* Hash table maintenance information */
528 	struct list_head uidhash_list;
529 	uid_t uid;
530 };
531 
532 extern struct user_struct *find_user(uid_t);
533 
534 extern struct user_struct root_user;
535 #define INIT_USER (&root_user)
536 
537 typedef struct prio_array prio_array_t;
538 struct backing_dev_info;
539 struct reclaim_state;
540 
541 #ifdef CONFIG_SCHEDSTATS
542 struct sched_info {
543 	/* cumulative counters */
544 	unsigned long	cpu_time,	/* time spent on the cpu */
545 			run_delay,	/* time spent waiting on a runqueue */
546 			pcnt;		/* # of timeslices run on this cpu */
547 
548 	/* timestamps */
549 	unsigned long	last_arrival,	/* when we last ran on a cpu */
550 			last_queued;	/* when we were last queued to run */
551 };
552 
553 extern struct file_operations proc_schedstat_operations;
554 #endif
555 
556 enum idle_type
557 {
558 	SCHED_IDLE,
559 	NOT_IDLE,
560 	NEWLY_IDLE,
561 	MAX_IDLE_TYPES
562 };
563 
564 /*
565  * sched-domains (multiprocessor balancing) declarations:
566  */
567 #define SCHED_LOAD_SCALE	128UL	/* increase resolution of load */
568 
569 #ifdef CONFIG_SMP
570 #define SD_LOAD_BALANCE		1	/* Do load balancing on this domain. */
571 #define SD_BALANCE_NEWIDLE	2	/* Balance when about to become idle */
572 #define SD_BALANCE_EXEC		4	/* Balance on exec */
573 #define SD_BALANCE_FORK		8	/* Balance on fork, clone */
574 #define SD_WAKE_IDLE		16	/* Wake to idle CPU on task wakeup */
575 #define SD_WAKE_AFFINE		32	/* Wake task to waking CPU */
576 #define SD_WAKE_BALANCE		64	/* Perform balancing at task wakeup */
577 #define SD_SHARE_CPUPOWER	128	/* Domain members share cpu power */
578 #define SD_POWERSAVINGS_BALANCE	256	/* Balance for power savings */
579 
580 #define BALANCE_FOR_POWER	((sched_mc_power_savings || sched_smt_power_savings) \
581 				 ? SD_POWERSAVINGS_BALANCE : 0)
582 
583 
584 struct sched_group {
585 	struct sched_group *next;	/* Must be a circular list */
586 	cpumask_t cpumask;
587 
588 	/*
589 	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
590 	 * single CPU. This is read only (except for setup, hotplug CPU).
591 	 */
592 	unsigned long cpu_power;
593 };
594 
595 struct sched_domain {
596 	/* These fields must be setup */
597 	struct sched_domain *parent;	/* top domain must be null terminated */
598 	struct sched_group *groups;	/* the balancing groups of the domain */
599 	cpumask_t span;			/* span of all CPUs in this domain */
600 	unsigned long min_interval;	/* Minimum balance interval ms */
601 	unsigned long max_interval;	/* Maximum balance interval ms */
602 	unsigned int busy_factor;	/* less balancing by factor if busy */
603 	unsigned int imbalance_pct;	/* No balance until over watermark */
604 	unsigned long long cache_hot_time; /* Task considered cache hot (ns) */
605 	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
606 	unsigned int per_cpu_gain;	/* CPU % gained by adding domain cpus */
607 	unsigned int busy_idx;
608 	unsigned int idle_idx;
609 	unsigned int newidle_idx;
610 	unsigned int wake_idx;
611 	unsigned int forkexec_idx;
612 	int flags;			/* See SD_* */
613 
614 	/* Runtime fields. */
615 	unsigned long last_balance;	/* init to jiffies. units in jiffies */
616 	unsigned int balance_interval;	/* initialise to 1. units in ms. */
617 	unsigned int nr_balance_failed; /* initialise to 0 */
618 
619 #ifdef CONFIG_SCHEDSTATS
620 	/* load_balance() stats */
621 	unsigned long lb_cnt[MAX_IDLE_TYPES];
622 	unsigned long lb_failed[MAX_IDLE_TYPES];
623 	unsigned long lb_balanced[MAX_IDLE_TYPES];
624 	unsigned long lb_imbalance[MAX_IDLE_TYPES];
625 	unsigned long lb_gained[MAX_IDLE_TYPES];
626 	unsigned long lb_hot_gained[MAX_IDLE_TYPES];
627 	unsigned long lb_nobusyg[MAX_IDLE_TYPES];
628 	unsigned long lb_nobusyq[MAX_IDLE_TYPES];
629 
630 	/* Active load balancing */
631 	unsigned long alb_cnt;
632 	unsigned long alb_failed;
633 	unsigned long alb_pushed;
634 
635 	/* SD_BALANCE_EXEC stats */
636 	unsigned long sbe_cnt;
637 	unsigned long sbe_balanced;
638 	unsigned long sbe_pushed;
639 
640 	/* SD_BALANCE_FORK stats */
641 	unsigned long sbf_cnt;
642 	unsigned long sbf_balanced;
643 	unsigned long sbf_pushed;
644 
645 	/* try_to_wake_up() stats */
646 	unsigned long ttwu_wake_remote;
647 	unsigned long ttwu_move_affine;
648 	unsigned long ttwu_move_balance;
649 #endif
650 };
651 
652 extern int partition_sched_domains(cpumask_t *partition1,
653 				    cpumask_t *partition2);
654 
655 /*
656  * Maximum cache size the migration-costs auto-tuning code will
657  * search from:
658  */
659 extern unsigned int max_cache_size;
660 
661 #endif	/* CONFIG_SMP */
662 
663 
664 struct io_context;			/* See blkdev.h */
665 void exit_io_context(void);
666 struct cpuset;
667 
668 #define NGROUPS_SMALL		32
669 #define NGROUPS_PER_BLOCK	((int)(PAGE_SIZE / sizeof(gid_t)))
670 struct group_info {
671 	int ngroups;
672 	atomic_t usage;
673 	gid_t small_block[NGROUPS_SMALL];
674 	int nblocks;
675 	gid_t *blocks[0];
676 };
677 
678 /*
679  * get_group_info() must be called with the owning task locked (via task_lock())
680  * when task != current.  The reason being that the vast majority of callers are
681  * looking at current->group_info, which can not be changed except by the
682  * current task.  Changing current->group_info requires the task lock, too.
683  */
684 #define get_group_info(group_info) do { \
685 	atomic_inc(&(group_info)->usage); \
686 } while (0)
687 
688 #define put_group_info(group_info) do { \
689 	if (atomic_dec_and_test(&(group_info)->usage)) \
690 		groups_free(group_info); \
691 } while (0)
692 
693 extern struct group_info *groups_alloc(int gidsetsize);
694 extern void groups_free(struct group_info *group_info);
695 extern int set_current_groups(struct group_info *group_info);
696 extern int groups_search(struct group_info *group_info, gid_t grp);
697 /* access the groups "array" with this macro */
698 #define GROUP_AT(gi, i) \
699     ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
700 
701 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
702 extern void prefetch_stack(struct task_struct*);
703 #else
704 static inline void prefetch_stack(struct task_struct *t) { }
705 #endif
706 
707 struct audit_context;		/* See audit.c */
708 struct mempolicy;
709 struct pipe_inode_info;
710 
711 enum sleep_type {
712 	SLEEP_NORMAL,
713 	SLEEP_NONINTERACTIVE,
714 	SLEEP_INTERACTIVE,
715 	SLEEP_INTERRUPTED,
716 };
717 
718 struct task_struct {
719 	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
720 	struct thread_info *thread_info;
721 	atomic_t usage;
722 	unsigned long flags;	/* per process flags, defined below */
723 	unsigned long ptrace;
724 
725 	int lock_depth;		/* BKL lock depth */
726 
727 #ifdef CONFIG_SMP
728 #ifdef __ARCH_WANT_UNLOCKED_CTXSW
729 	int oncpu;
730 #endif
731 #endif
732 	int load_weight;	/* for niceness load balancing purposes */
733 	int prio, static_prio, normal_prio;
734 	struct list_head run_list;
735 	prio_array_t *array;
736 
737 	unsigned short ioprio;
738 	unsigned int btrace_seq;
739 
740 	unsigned long sleep_avg;
741 	unsigned long long timestamp, last_ran;
742 	unsigned long long sched_time; /* sched_clock time spent running */
743 	enum sleep_type sleep_type;
744 
745 	unsigned long policy;
746 	cpumask_t cpus_allowed;
747 	unsigned int time_slice, first_time_slice;
748 
749 #ifdef CONFIG_SCHEDSTATS
750 	struct sched_info sched_info;
751 #endif
752 
753 	struct list_head tasks;
754 	/*
755 	 * ptrace_list/ptrace_children forms the list of my children
756 	 * that were stolen by a ptracer.
757 	 */
758 	struct list_head ptrace_children;
759 	struct list_head ptrace_list;
760 
761 	struct mm_struct *mm, *active_mm;
762 
763 /* task state */
764 	struct linux_binfmt *binfmt;
765 	long exit_state;
766 	int exit_code, exit_signal;
767 	int pdeath_signal;  /*  The signal sent when the parent dies  */
768 	/* ??? */
769 	unsigned long personality;
770 	unsigned did_exec:1;
771 	pid_t pid;
772 	pid_t tgid;
773 	/*
774 	 * pointers to (original) parent process, youngest child, younger sibling,
775 	 * older sibling, respectively.  (p->father can be replaced with
776 	 * p->parent->pid)
777 	 */
778 	struct task_struct *real_parent; /* real parent process (when being debugged) */
779 	struct task_struct *parent;	/* parent process */
780 	/*
781 	 * children/sibling forms the list of my children plus the
782 	 * tasks I'm ptracing.
783 	 */
784 	struct list_head children;	/* list of my children */
785 	struct list_head sibling;	/* linkage in my parent's children list */
786 	struct task_struct *group_leader;	/* threadgroup leader */
787 
788 	/* PID/PID hash table linkage. */
789 	struct pid_link pids[PIDTYPE_MAX];
790 	struct list_head thread_group;
791 
792 	struct completion *vfork_done;		/* for vfork() */
793 	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
794 	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
795 
796 	unsigned long rt_priority;
797 	cputime_t utime, stime;
798 	unsigned long nvcsw, nivcsw; /* context switch counts */
799 	struct timespec start_time;
800 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
801 	unsigned long min_flt, maj_flt;
802 
803   	cputime_t it_prof_expires, it_virt_expires;
804 	unsigned long long it_sched_expires;
805 	struct list_head cpu_timers[3];
806 
807 /* process credentials */
808 	uid_t uid,euid,suid,fsuid;
809 	gid_t gid,egid,sgid,fsgid;
810 	struct group_info *group_info;
811 	kernel_cap_t   cap_effective, cap_inheritable, cap_permitted;
812 	unsigned keep_capabilities:1;
813 	struct user_struct *user;
814 #ifdef CONFIG_KEYS
815 	struct key *request_key_auth;	/* assumed request_key authority */
816 	struct key *thread_keyring;	/* keyring private to this thread */
817 	unsigned char jit_keyring;	/* default keyring to attach requested keys to */
818 #endif
819 	int oomkilladj; /* OOM kill score adjustment (bit shift). */
820 	char comm[TASK_COMM_LEN]; /* executable name excluding path
821 				     - access with [gs]et_task_comm (which lock
822 				       it with task_lock())
823 				     - initialized normally by flush_old_exec */
824 /* file system info */
825 	int link_count, total_link_count;
826 /* ipc stuff */
827 	struct sysv_sem sysvsem;
828 /* CPU-specific state of this task */
829 	struct thread_struct thread;
830 /* filesystem information */
831 	struct fs_struct *fs;
832 /* open file information */
833 	struct files_struct *files;
834 /* namespace */
835 	struct namespace *namespace;
836 /* signal handlers */
837 	struct signal_struct *signal;
838 	struct sighand_struct *sighand;
839 
840 	sigset_t blocked, real_blocked;
841 	sigset_t saved_sigmask;		/* To be restored with TIF_RESTORE_SIGMASK */
842 	struct sigpending pending;
843 
844 	unsigned long sas_ss_sp;
845 	size_t sas_ss_size;
846 	int (*notifier)(void *priv);
847 	void *notifier_data;
848 	sigset_t *notifier_mask;
849 
850 	void *security;
851 	struct audit_context *audit_context;
852 	seccomp_t seccomp;
853 
854 /* Thread group tracking */
855    	u32 parent_exec_id;
856    	u32 self_exec_id;
857 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
858 	spinlock_t alloc_lock;
859 
860 	/* Protection of the PI data structures: */
861 	spinlock_t pi_lock;
862 
863 #ifdef CONFIG_RT_MUTEXES
864 	/* PI waiters blocked on a rt_mutex held by this task */
865 	struct plist_head pi_waiters;
866 	/* Deadlock detection and priority inheritance handling */
867 	struct rt_mutex_waiter *pi_blocked_on;
868 # ifdef CONFIG_DEBUG_RT_MUTEXES
869 	spinlock_t held_list_lock;
870 	struct list_head held_list_head;
871 # endif
872 #endif
873 
874 #ifdef CONFIG_DEBUG_MUTEXES
875 	/* mutex deadlock detection */
876 	struct mutex_waiter *blocked_on;
877 #endif
878 
879 /* journalling filesystem info */
880 	void *journal_info;
881 
882 /* VM state */
883 	struct reclaim_state *reclaim_state;
884 
885 	struct backing_dev_info *backing_dev_info;
886 
887 	struct io_context *io_context;
888 
889 	unsigned long ptrace_message;
890 	siginfo_t *last_siginfo; /* For ptrace use.  */
891 /*
892  * current io wait handle: wait queue entry to use for io waits
893  * If this thread is processing aio, this points at the waitqueue
894  * inside the currently handled kiocb. It may be NULL (i.e. default
895  * to a stack based synchronous wait) if its doing sync IO.
896  */
897 	wait_queue_t *io_wait;
898 /* i/o counters(bytes read/written, #syscalls */
899 	u64 rchar, wchar, syscr, syscw;
900 #if defined(CONFIG_BSD_PROCESS_ACCT)
901 	u64 acct_rss_mem1;	/* accumulated rss usage */
902 	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
903 	clock_t acct_stimexpd;	/* clock_t-converted stime since last update */
904 #endif
905 #ifdef CONFIG_NUMA
906   	struct mempolicy *mempolicy;
907 	short il_next;
908 #endif
909 #ifdef CONFIG_CPUSETS
910 	struct cpuset *cpuset;
911 	nodemask_t mems_allowed;
912 	int cpuset_mems_generation;
913 	int cpuset_mem_spread_rotor;
914 #endif
915 	struct robust_list_head __user *robust_list;
916 #ifdef CONFIG_COMPAT
917 	struct compat_robust_list_head __user *compat_robust_list;
918 #endif
919 	struct list_head pi_state_list;
920 	struct futex_pi_state *pi_state_cache;
921 
922 	atomic_t fs_excl;	/* holding fs exclusive resources */
923 	struct rcu_head rcu;
924 
925 	/*
926 	 * cache last used pipe for splice
927 	 */
928 	struct pipe_inode_info *splice_pipe;
929 };
930 
931 static inline pid_t process_group(struct task_struct *tsk)
932 {
933 	return tsk->signal->pgrp;
934 }
935 
936 /**
937  * pid_alive - check that a task structure is not stale
938  * @p: Task structure to be checked.
939  *
940  * Test if a process is not yet dead (at most zombie state)
941  * If pid_alive fails, then pointers within the task structure
942  * can be stale and must not be dereferenced.
943  */
944 static inline int pid_alive(struct task_struct *p)
945 {
946 	return p->pids[PIDTYPE_PID].pid != NULL;
947 }
948 
949 extern void free_task(struct task_struct *tsk);
950 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
951 
952 extern void __put_task_struct(struct task_struct *t);
953 
954 static inline void put_task_struct(struct task_struct *t)
955 {
956 	if (atomic_dec_and_test(&t->usage))
957 		__put_task_struct(t);
958 }
959 
960 /*
961  * Per process flags
962  */
963 #define PF_ALIGNWARN	0x00000001	/* Print alignment warning msgs */
964 					/* Not implemented yet, only for 486*/
965 #define PF_STARTING	0x00000002	/* being created */
966 #define PF_EXITING	0x00000004	/* getting shut down */
967 #define PF_DEAD		0x00000008	/* Dead */
968 #define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
969 #define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
970 #define PF_DUMPCORE	0x00000200	/* dumped core */
971 #define PF_SIGNALED	0x00000400	/* killed by a signal */
972 #define PF_MEMALLOC	0x00000800	/* Allocating memory */
973 #define PF_FLUSHER	0x00001000	/* responsible for disk writeback */
974 #define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
975 #define PF_FREEZE	0x00004000	/* this task is being frozen for suspend now */
976 #define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
977 #define PF_FROZEN	0x00010000	/* frozen for system suspend */
978 #define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
979 #define PF_KSWAPD	0x00040000	/* I am kswapd */
980 #define PF_SWAPOFF	0x00080000	/* I am in swapoff */
981 #define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
982 #define PF_BORROWED_MM	0x00200000	/* I am a kthread doing use_mm */
983 #define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
984 #define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
985 #define PF_SPREAD_PAGE	0x01000000	/* Spread page cache over cpuset */
986 #define PF_SPREAD_SLAB	0x02000000	/* Spread some slab caches over cpuset */
987 #define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
988 #define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
989 
990 /*
991  * Only the _current_ task can read/write to tsk->flags, but other
992  * tasks can access tsk->flags in readonly mode for example
993  * with tsk_used_math (like during threaded core dumping).
994  * There is however an exception to this rule during ptrace
995  * or during fork: the ptracer task is allowed to write to the
996  * child->flags of its traced child (same goes for fork, the parent
997  * can write to the child->flags), because we're guaranteed the
998  * child is not running and in turn not changing child->flags
999  * at the same time the parent does it.
1000  */
1001 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1002 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1003 #define clear_used_math() clear_stopped_child_used_math(current)
1004 #define set_used_math() set_stopped_child_used_math(current)
1005 #define conditional_stopped_child_used_math(condition, child) \
1006 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1007 #define conditional_used_math(condition) \
1008 	conditional_stopped_child_used_math(condition, current)
1009 #define copy_to_stopped_child_used_math(child) \
1010 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1011 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1012 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1013 #define used_math() tsk_used_math(current)
1014 
1015 #ifdef CONFIG_SMP
1016 extern int set_cpus_allowed(task_t *p, cpumask_t new_mask);
1017 #else
1018 static inline int set_cpus_allowed(task_t *p, cpumask_t new_mask)
1019 {
1020 	if (!cpu_isset(0, new_mask))
1021 		return -EINVAL;
1022 	return 0;
1023 }
1024 #endif
1025 
1026 extern unsigned long long sched_clock(void);
1027 extern unsigned long long current_sched_time(const task_t *current_task);
1028 
1029 /* sched_exec is called by processes performing an exec */
1030 #ifdef CONFIG_SMP
1031 extern void sched_exec(void);
1032 #else
1033 #define sched_exec()   {}
1034 #endif
1035 
1036 #ifdef CONFIG_HOTPLUG_CPU
1037 extern void idle_task_exit(void);
1038 #else
1039 static inline void idle_task_exit(void) {}
1040 #endif
1041 
1042 extern void sched_idle_next(void);
1043 
1044 #ifdef CONFIG_RT_MUTEXES
1045 extern int rt_mutex_getprio(task_t *p);
1046 extern void rt_mutex_setprio(task_t *p, int prio);
1047 extern void rt_mutex_adjust_pi(task_t *p);
1048 #else
1049 static inline int rt_mutex_getprio(task_t *p)
1050 {
1051 	return p->normal_prio;
1052 }
1053 # define rt_mutex_adjust_pi(p)		do { } while (0)
1054 #endif
1055 
1056 extern void set_user_nice(task_t *p, long nice);
1057 extern int task_prio(const task_t *p);
1058 extern int task_nice(const task_t *p);
1059 extern int can_nice(const task_t *p, const int nice);
1060 extern int task_curr(const task_t *p);
1061 extern int idle_cpu(int cpu);
1062 extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1063 extern task_t *idle_task(int cpu);
1064 extern task_t *curr_task(int cpu);
1065 extern void set_curr_task(int cpu, task_t *p);
1066 
1067 void yield(void);
1068 
1069 /*
1070  * The default (Linux) execution domain.
1071  */
1072 extern struct exec_domain	default_exec_domain;
1073 
1074 union thread_union {
1075 	struct thread_info thread_info;
1076 	unsigned long stack[THREAD_SIZE/sizeof(long)];
1077 };
1078 
1079 #ifndef __HAVE_ARCH_KSTACK_END
1080 static inline int kstack_end(void *addr)
1081 {
1082 	/* Reliable end of stack detection:
1083 	 * Some APM bios versions misalign the stack
1084 	 */
1085 	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1086 }
1087 #endif
1088 
1089 extern union thread_union init_thread_union;
1090 extern struct task_struct init_task;
1091 
1092 extern struct   mm_struct init_mm;
1093 
1094 #define find_task_by_pid(nr)	find_task_by_pid_type(PIDTYPE_PID, nr)
1095 extern struct task_struct *find_task_by_pid_type(int type, int pid);
1096 extern void set_special_pids(pid_t session, pid_t pgrp);
1097 extern void __set_special_pids(pid_t session, pid_t pgrp);
1098 
1099 /* per-UID process charging. */
1100 extern struct user_struct * alloc_uid(uid_t);
1101 static inline struct user_struct *get_uid(struct user_struct *u)
1102 {
1103 	atomic_inc(&u->__count);
1104 	return u;
1105 }
1106 extern void free_uid(struct user_struct *);
1107 extern void switch_uid(struct user_struct *);
1108 
1109 #include <asm/current.h>
1110 
1111 extern void do_timer(struct pt_regs *);
1112 
1113 extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state));
1114 extern int FASTCALL(wake_up_process(struct task_struct * tsk));
1115 extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
1116 						unsigned long clone_flags));
1117 #ifdef CONFIG_SMP
1118  extern void kick_process(struct task_struct *tsk);
1119 #else
1120  static inline void kick_process(struct task_struct *tsk) { }
1121 #endif
1122 extern void FASTCALL(sched_fork(task_t * p, int clone_flags));
1123 extern void FASTCALL(sched_exit(task_t * p));
1124 
1125 extern int in_group_p(gid_t);
1126 extern int in_egroup_p(gid_t);
1127 
1128 extern void proc_caches_init(void);
1129 extern void flush_signals(struct task_struct *);
1130 extern void flush_signal_handlers(struct task_struct *, int force_default);
1131 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1132 
1133 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1134 {
1135 	unsigned long flags;
1136 	int ret;
1137 
1138 	spin_lock_irqsave(&tsk->sighand->siglock, flags);
1139 	ret = dequeue_signal(tsk, mask, info);
1140 	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1141 
1142 	return ret;
1143 }
1144 
1145 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1146 			      sigset_t *mask);
1147 extern void unblock_all_signals(void);
1148 extern void release_task(struct task_struct * p);
1149 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1150 extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
1151 extern int force_sigsegv(int, struct task_struct *);
1152 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1153 extern int __kill_pg_info(int sig, struct siginfo *info, pid_t pgrp);
1154 extern int kill_pg_info(int, struct siginfo *, pid_t);
1155 extern int kill_proc_info(int, struct siginfo *, pid_t);
1156 extern int kill_proc_info_as_uid(int, struct siginfo *, pid_t, uid_t, uid_t, u32);
1157 extern void do_notify_parent(struct task_struct *, int);
1158 extern void force_sig(int, struct task_struct *);
1159 extern void force_sig_specific(int, struct task_struct *);
1160 extern int send_sig(int, struct task_struct *, int);
1161 extern void zap_other_threads(struct task_struct *p);
1162 extern int kill_pg(pid_t, int, int);
1163 extern int kill_proc(pid_t, int, int);
1164 extern struct sigqueue *sigqueue_alloc(void);
1165 extern void sigqueue_free(struct sigqueue *);
1166 extern int send_sigqueue(int, struct sigqueue *,  struct task_struct *);
1167 extern int send_group_sigqueue(int, struct sigqueue *,  struct task_struct *);
1168 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
1169 extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1170 
1171 /* These can be the second arg to send_sig_info/send_group_sig_info.  */
1172 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
1173 #define SEND_SIG_PRIV	((struct siginfo *) 1)
1174 #define SEND_SIG_FORCED	((struct siginfo *) 2)
1175 
1176 static inline int is_si_special(const struct siginfo *info)
1177 {
1178 	return info <= SEND_SIG_FORCED;
1179 }
1180 
1181 /* True if we are on the alternate signal stack.  */
1182 
1183 static inline int on_sig_stack(unsigned long sp)
1184 {
1185 	return (sp - current->sas_ss_sp < current->sas_ss_size);
1186 }
1187 
1188 static inline int sas_ss_flags(unsigned long sp)
1189 {
1190 	return (current->sas_ss_size == 0 ? SS_DISABLE
1191 		: on_sig_stack(sp) ? SS_ONSTACK : 0);
1192 }
1193 
1194 /*
1195  * Routines for handling mm_structs
1196  */
1197 extern struct mm_struct * mm_alloc(void);
1198 
1199 /* mmdrop drops the mm and the page tables */
1200 extern void FASTCALL(__mmdrop(struct mm_struct *));
1201 static inline void mmdrop(struct mm_struct * mm)
1202 {
1203 	if (atomic_dec_and_test(&mm->mm_count))
1204 		__mmdrop(mm);
1205 }
1206 
1207 /* mmput gets rid of the mappings and all user-space */
1208 extern void mmput(struct mm_struct *);
1209 /* Grab a reference to a task's mm, if it is not already going away */
1210 extern struct mm_struct *get_task_mm(struct task_struct *task);
1211 /* Remove the current tasks stale references to the old mm_struct */
1212 extern void mm_release(struct task_struct *, struct mm_struct *);
1213 
1214 extern int  copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1215 extern void flush_thread(void);
1216 extern void exit_thread(void);
1217 
1218 extern void exit_files(struct task_struct *);
1219 extern void __cleanup_signal(struct signal_struct *);
1220 extern void __cleanup_sighand(struct sighand_struct *);
1221 extern void exit_itimers(struct signal_struct *);
1222 
1223 extern NORET_TYPE void do_group_exit(int);
1224 
1225 extern void daemonize(const char *, ...);
1226 extern int allow_signal(int);
1227 extern int disallow_signal(int);
1228 extern task_t *child_reaper;
1229 
1230 extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1231 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1232 task_t *fork_idle(int);
1233 
1234 extern void set_task_comm(struct task_struct *tsk, char *from);
1235 extern void get_task_comm(char *to, struct task_struct *tsk);
1236 
1237 #ifdef CONFIG_SMP
1238 extern void wait_task_inactive(task_t * p);
1239 #else
1240 #define wait_task_inactive(p)	do { } while (0)
1241 #endif
1242 
1243 #define remove_parent(p)	list_del_init(&(p)->sibling)
1244 #define add_parent(p)		list_add_tail(&(p)->sibling,&(p)->parent->children)
1245 
1246 #define next_task(p)	list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
1247 
1248 #define for_each_process(p) \
1249 	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1250 
1251 /*
1252  * Careful: do_each_thread/while_each_thread is a double loop so
1253  *          'break' will not work as expected - use goto instead.
1254  */
1255 #define do_each_thread(g, t) \
1256 	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1257 
1258 #define while_each_thread(g, t) \
1259 	while ((t = next_thread(t)) != g)
1260 
1261 /* de_thread depends on thread_group_leader not being a pid based check */
1262 #define thread_group_leader(p)	(p == p->group_leader)
1263 
1264 static inline task_t *next_thread(const task_t *p)
1265 {
1266 	return list_entry(rcu_dereference(p->thread_group.next),
1267 				task_t, thread_group);
1268 }
1269 
1270 static inline int thread_group_empty(task_t *p)
1271 {
1272 	return list_empty(&p->thread_group);
1273 }
1274 
1275 #define delay_group_leader(p) \
1276 		(thread_group_leader(p) && !thread_group_empty(p))
1277 
1278 /*
1279  * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
1280  * subscriptions and synchronises with wait4().  Also used in procfs.  Also
1281  * pins the final release of task.io_context.  Also protects ->cpuset.
1282  *
1283  * Nests both inside and outside of read_lock(&tasklist_lock).
1284  * It must not be nested with write_lock_irq(&tasklist_lock),
1285  * neither inside nor outside.
1286  */
1287 static inline void task_lock(struct task_struct *p)
1288 {
1289 	spin_lock(&p->alloc_lock);
1290 }
1291 
1292 static inline void task_unlock(struct task_struct *p)
1293 {
1294 	spin_unlock(&p->alloc_lock);
1295 }
1296 
1297 extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
1298 							unsigned long *flags);
1299 
1300 static inline void unlock_task_sighand(struct task_struct *tsk,
1301 						unsigned long *flags)
1302 {
1303 	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
1304 }
1305 
1306 #ifndef __HAVE_THREAD_FUNCTIONS
1307 
1308 #define task_thread_info(task) (task)->thread_info
1309 #define task_stack_page(task) ((void*)((task)->thread_info))
1310 
1311 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
1312 {
1313 	*task_thread_info(p) = *task_thread_info(org);
1314 	task_thread_info(p)->task = p;
1315 }
1316 
1317 static inline unsigned long *end_of_stack(struct task_struct *p)
1318 {
1319 	return (unsigned long *)(p->thread_info + 1);
1320 }
1321 
1322 #endif
1323 
1324 /* set thread flags in other task's structures
1325  * - see asm/thread_info.h for TIF_xxxx flags available
1326  */
1327 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1328 {
1329 	set_ti_thread_flag(task_thread_info(tsk), flag);
1330 }
1331 
1332 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1333 {
1334 	clear_ti_thread_flag(task_thread_info(tsk), flag);
1335 }
1336 
1337 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1338 {
1339 	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1340 }
1341 
1342 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1343 {
1344 	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1345 }
1346 
1347 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1348 {
1349 	return test_ti_thread_flag(task_thread_info(tsk), flag);
1350 }
1351 
1352 static inline void set_tsk_need_resched(struct task_struct *tsk)
1353 {
1354 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1355 }
1356 
1357 static inline void clear_tsk_need_resched(struct task_struct *tsk)
1358 {
1359 	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1360 }
1361 
1362 static inline int signal_pending(struct task_struct *p)
1363 {
1364 	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1365 }
1366 
1367 static inline int need_resched(void)
1368 {
1369 	return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1370 }
1371 
1372 /*
1373  * cond_resched() and cond_resched_lock(): latency reduction via
1374  * explicit rescheduling in places that are safe. The return
1375  * value indicates whether a reschedule was done in fact.
1376  * cond_resched_lock() will drop the spinlock before scheduling,
1377  * cond_resched_softirq() will enable bhs before scheduling.
1378  */
1379 extern int cond_resched(void);
1380 extern int cond_resched_lock(spinlock_t * lock);
1381 extern int cond_resched_softirq(void);
1382 
1383 /*
1384  * Does a critical section need to be broken due to another
1385  * task waiting?:
1386  */
1387 #if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
1388 # define need_lockbreak(lock) ((lock)->break_lock)
1389 #else
1390 # define need_lockbreak(lock) 0
1391 #endif
1392 
1393 /*
1394  * Does a critical section need to be broken due to another
1395  * task waiting or preemption being signalled:
1396  */
1397 static inline int lock_need_resched(spinlock_t *lock)
1398 {
1399 	if (need_lockbreak(lock) || need_resched())
1400 		return 1;
1401 	return 0;
1402 }
1403 
1404 /* Reevaluate whether the task has signals pending delivery.
1405    This is required every time the blocked sigset_t changes.
1406    callers must hold sighand->siglock.  */
1407 
1408 extern FASTCALL(void recalc_sigpending_tsk(struct task_struct *t));
1409 extern void recalc_sigpending(void);
1410 
1411 extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1412 
1413 /*
1414  * Wrappers for p->thread_info->cpu access. No-op on UP.
1415  */
1416 #ifdef CONFIG_SMP
1417 
1418 static inline unsigned int task_cpu(const struct task_struct *p)
1419 {
1420 	return task_thread_info(p)->cpu;
1421 }
1422 
1423 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1424 {
1425 	task_thread_info(p)->cpu = cpu;
1426 }
1427 
1428 #else
1429 
1430 static inline unsigned int task_cpu(const struct task_struct *p)
1431 {
1432 	return 0;
1433 }
1434 
1435 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1436 {
1437 }
1438 
1439 #endif /* CONFIG_SMP */
1440 
1441 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1442 extern void arch_pick_mmap_layout(struct mm_struct *mm);
1443 #else
1444 static inline void arch_pick_mmap_layout(struct mm_struct *mm)
1445 {
1446 	mm->mmap_base = TASK_UNMAPPED_BASE;
1447 	mm->get_unmapped_area = arch_get_unmapped_area;
1448 	mm->unmap_area = arch_unmap_area;
1449 }
1450 #endif
1451 
1452 extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
1453 extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
1454 
1455 #include <linux/sysdev.h>
1456 extern int sched_mc_power_savings, sched_smt_power_savings;
1457 extern struct sysdev_attribute attr_sched_mc_power_savings, attr_sched_smt_power_savings;
1458 extern int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls);
1459 
1460 extern void normalize_rt_tasks(void);
1461 
1462 #ifdef CONFIG_PM
1463 /*
1464  * Check if a process has been frozen
1465  */
1466 static inline int frozen(struct task_struct *p)
1467 {
1468 	return p->flags & PF_FROZEN;
1469 }
1470 
1471 /*
1472  * Check if there is a request to freeze a process
1473  */
1474 static inline int freezing(struct task_struct *p)
1475 {
1476 	return p->flags & PF_FREEZE;
1477 }
1478 
1479 /*
1480  * Request that a process be frozen
1481  * FIXME: SMP problem. We may not modify other process' flags!
1482  */
1483 static inline void freeze(struct task_struct *p)
1484 {
1485 	p->flags |= PF_FREEZE;
1486 }
1487 
1488 /*
1489  * Wake up a frozen process
1490  */
1491 static inline int thaw_process(struct task_struct *p)
1492 {
1493 	if (frozen(p)) {
1494 		p->flags &= ~PF_FROZEN;
1495 		wake_up_process(p);
1496 		return 1;
1497 	}
1498 	return 0;
1499 }
1500 
1501 /*
1502  * freezing is complete, mark process as frozen
1503  */
1504 static inline void frozen_process(struct task_struct *p)
1505 {
1506 	p->flags = (p->flags & ~PF_FREEZE) | PF_FROZEN;
1507 }
1508 
1509 extern void refrigerator(void);
1510 extern int freeze_processes(void);
1511 extern void thaw_processes(void);
1512 
1513 static inline int try_to_freeze(void)
1514 {
1515 	if (freezing(current)) {
1516 		refrigerator();
1517 		return 1;
1518 	} else
1519 		return 0;
1520 }
1521 #else
1522 static inline int frozen(struct task_struct *p) { return 0; }
1523 static inline int freezing(struct task_struct *p) { return 0; }
1524 static inline void freeze(struct task_struct *p) { BUG(); }
1525 static inline int thaw_process(struct task_struct *p) { return 1; }
1526 static inline void frozen_process(struct task_struct *p) { BUG(); }
1527 
1528 static inline void refrigerator(void) {}
1529 static inline int freeze_processes(void) { BUG(); return 0; }
1530 static inline void thaw_processes(void) {}
1531 
1532 static inline int try_to_freeze(void) { return 0; }
1533 
1534 #endif /* CONFIG_PM */
1535 #endif /* __KERNEL__ */
1536 
1537 #endif
1538