xref: /linux/include/linux/sched.h (revision 54a8a2220c936a47840c9a3d74910c5a56fae2ed)
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 
38 #include <linux/auxvec.h>	/* For AT_VECTOR_SIZE */
39 
40 struct exec_domain;
41 
42 /*
43  * cloning flags:
44  */
45 #define CSIGNAL		0x000000ff	/* signal mask to be sent at exit */
46 #define CLONE_VM	0x00000100	/* set if VM shared between processes */
47 #define CLONE_FS	0x00000200	/* set if fs info shared between processes */
48 #define CLONE_FILES	0x00000400	/* set if open files shared between processes */
49 #define CLONE_SIGHAND	0x00000800	/* set if signal handlers and blocked signals shared */
50 #define CLONE_PTRACE	0x00002000	/* set if we want to let tracing continue on the child too */
51 #define CLONE_VFORK	0x00004000	/* set if the parent wants the child to wake it up on mm_release */
52 #define CLONE_PARENT	0x00008000	/* set if we want to have the same parent as the cloner */
53 #define CLONE_THREAD	0x00010000	/* Same thread group? */
54 #define CLONE_NEWNS	0x00020000	/* New namespace group? */
55 #define CLONE_SYSVSEM	0x00040000	/* share system V SEM_UNDO semantics */
56 #define CLONE_SETTLS	0x00080000	/* create a new TLS for the child */
57 #define CLONE_PARENT_SETTID	0x00100000	/* set the TID in the parent */
58 #define CLONE_CHILD_CLEARTID	0x00200000	/* clear the TID in the child */
59 #define CLONE_DETACHED		0x00400000	/* Unused, ignored */
60 #define CLONE_UNTRACED		0x00800000	/* set if the tracing process can't force CLONE_PTRACE on this clone */
61 #define CLONE_CHILD_SETTID	0x01000000	/* set the TID in the child */
62 #define CLONE_STOPPED		0x02000000	/* Start in stopped state */
63 
64 /*
65  * List of flags we want to share for kernel threads,
66  * if only because they are not used by them anyway.
67  */
68 #define CLONE_KERNEL	(CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
69 
70 /*
71  * These are the constant used to fake the fixed-point load-average
72  * counting. Some notes:
73  *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
74  *    a load-average precision of 10 bits integer + 11 bits fractional
75  *  - if you want to count load-averages more often, you need more
76  *    precision, or rounding will get you. With 2-second counting freq,
77  *    the EXP_n values would be 1981, 2034 and 2043 if still using only
78  *    11 bit fractions.
79  */
80 extern unsigned long avenrun[];		/* Load averages */
81 
82 #define FSHIFT		11		/* nr of bits of precision */
83 #define FIXED_1		(1<<FSHIFT)	/* 1.0 as fixed-point */
84 #define LOAD_FREQ	(5*HZ)		/* 5 sec intervals */
85 #define EXP_1		1884		/* 1/exp(5sec/1min) as fixed-point */
86 #define EXP_5		2014		/* 1/exp(5sec/5min) */
87 #define EXP_15		2037		/* 1/exp(5sec/15min) */
88 
89 #define CALC_LOAD(load,exp,n) \
90 	load *= exp; \
91 	load += n*(FIXED_1-exp); \
92 	load >>= FSHIFT;
93 
94 extern unsigned long total_forks;
95 extern int nr_threads;
96 extern int last_pid;
97 DECLARE_PER_CPU(unsigned long, process_counts);
98 extern int nr_processes(void);
99 extern unsigned long nr_running(void);
100 extern unsigned long nr_uninterruptible(void);
101 extern unsigned long nr_iowait(void);
102 
103 #include <linux/time.h>
104 #include <linux/param.h>
105 #include <linux/resource.h>
106 #include <linux/timer.h>
107 
108 #include <asm/processor.h>
109 
110 /*
111  * Task state bitmask. NOTE! These bits are also
112  * encoded in fs/proc/array.c: get_task_state().
113  *
114  * We have two separate sets of flags: task->state
115  * is about runnability, while task->exit_state are
116  * about the task exiting. Confusing, but this way
117  * modifying one set can't modify the other one by
118  * mistake.
119  */
120 #define TASK_RUNNING		0
121 #define TASK_INTERRUPTIBLE	1
122 #define TASK_UNINTERRUPTIBLE	2
123 #define TASK_STOPPED		4
124 #define TASK_TRACED		8
125 /* in tsk->exit_state */
126 #define EXIT_ZOMBIE		16
127 #define EXIT_DEAD		32
128 /* in tsk->state again */
129 #define TASK_NONINTERACTIVE	64
130 
131 #define __set_task_state(tsk, state_value)		\
132 	do { (tsk)->state = (state_value); } while (0)
133 #define set_task_state(tsk, state_value)		\
134 	set_mb((tsk)->state, (state_value))
135 
136 /*
137  * set_current_state() includes a barrier so that the write of current->state
138  * is correctly serialised wrt the caller's subsequent test of whether to
139  * actually sleep:
140  *
141  *	set_current_state(TASK_UNINTERRUPTIBLE);
142  *	if (do_i_need_to_sleep())
143  *		schedule();
144  *
145  * If the caller does not need such serialisation then use __set_current_state()
146  */
147 #define __set_current_state(state_value)			\
148 	do { current->state = (state_value); } while (0)
149 #define set_current_state(state_value)		\
150 	set_mb(current->state, (state_value))
151 
152 /* Task command name length */
153 #define TASK_COMM_LEN 16
154 
155 /*
156  * Scheduling policies
157  */
158 #define SCHED_NORMAL		0
159 #define SCHED_FIFO		1
160 #define SCHED_RR		2
161 
162 struct sched_param {
163 	int sched_priority;
164 };
165 
166 #ifdef __KERNEL__
167 
168 #include <linux/spinlock.h>
169 
170 /*
171  * This serializes "schedule()" and also protects
172  * the run-queue from deletions/modifications (but
173  * _adding_ to the beginning of the run-queue has
174  * a separate lock).
175  */
176 extern rwlock_t tasklist_lock;
177 extern spinlock_t mmlist_lock;
178 
179 typedef struct task_struct task_t;
180 
181 extern void sched_init(void);
182 extern void sched_init_smp(void);
183 extern void init_idle(task_t *idle, int cpu);
184 
185 extern cpumask_t nohz_cpu_mask;
186 
187 extern void show_state(void);
188 extern void show_regs(struct pt_regs *);
189 
190 /*
191  * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
192  * task), SP is the stack pointer of the first frame that should be shown in the back
193  * trace (or NULL if the entire call-chain of the task should be shown).
194  */
195 extern void show_stack(struct task_struct *task, unsigned long *sp);
196 
197 void io_schedule(void);
198 long io_schedule_timeout(long timeout);
199 
200 extern void cpu_init (void);
201 extern void trap_init(void);
202 extern void update_process_times(int user);
203 extern void scheduler_tick(void);
204 
205 #ifdef CONFIG_DETECT_SOFTLOCKUP
206 extern void softlockup_tick(struct pt_regs *regs);
207 extern void spawn_softlockup_task(void);
208 extern void touch_softlockup_watchdog(void);
209 #else
210 static inline void softlockup_tick(struct pt_regs *regs)
211 {
212 }
213 static inline void spawn_softlockup_task(void)
214 {
215 }
216 static inline void touch_softlockup_watchdog(void)
217 {
218 }
219 #endif
220 
221 
222 /* Attach to any functions which should be ignored in wchan output. */
223 #define __sched		__attribute__((__section__(".sched.text")))
224 /* Is this address in the __sched functions? */
225 extern int in_sched_functions(unsigned long addr);
226 
227 #define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
228 extern signed long FASTCALL(schedule_timeout(signed long timeout));
229 extern signed long schedule_timeout_interruptible(signed long timeout);
230 extern signed long schedule_timeout_uninterruptible(signed long timeout);
231 asmlinkage void schedule(void);
232 
233 struct namespace;
234 
235 /* Maximum number of active map areas.. This is a random (large) number */
236 #define DEFAULT_MAX_MAP_COUNT	65536
237 
238 extern int sysctl_max_map_count;
239 
240 #include <linux/aio.h>
241 
242 extern unsigned long
243 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
244 		       unsigned long, unsigned long);
245 extern unsigned long
246 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
247 			  unsigned long len, unsigned long pgoff,
248 			  unsigned long flags);
249 extern void arch_unmap_area(struct mm_struct *, unsigned long);
250 extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
251 
252 #define set_mm_counter(mm, member, value) (mm)->_##member = (value)
253 #define get_mm_counter(mm, member) ((mm)->_##member)
254 #define add_mm_counter(mm, member, value) (mm)->_##member += (value)
255 #define inc_mm_counter(mm, member) (mm)->_##member++
256 #define dec_mm_counter(mm, member) (mm)->_##member--
257 typedef unsigned long mm_counter_t;
258 
259 struct mm_struct {
260 	struct vm_area_struct * mmap;		/* list of VMAs */
261 	struct rb_root mm_rb;
262 	struct vm_area_struct * mmap_cache;	/* last find_vma result */
263 	unsigned long (*get_unmapped_area) (struct file *filp,
264 				unsigned long addr, unsigned long len,
265 				unsigned long pgoff, unsigned long flags);
266 	void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
267         unsigned long mmap_base;		/* base of mmap area */
268         unsigned long cached_hole_size;         /* if non-zero, the largest hole below free_area_cache */
269 	unsigned long free_area_cache;		/* first hole of size cached_hole_size or larger */
270 	pgd_t * pgd;
271 	atomic_t mm_users;			/* How many users with user space? */
272 	atomic_t mm_count;			/* How many references to "struct mm_struct" (users count as 1) */
273 	int map_count;				/* number of VMAs */
274 	struct rw_semaphore mmap_sem;
275 	spinlock_t page_table_lock;		/* Protects page tables and some counters */
276 
277 	struct list_head mmlist;		/* List of maybe swapped mm's.  These are globally strung
278 						 * together off init_mm.mmlist, and are protected
279 						 * by mmlist_lock
280 						 */
281 
282 	unsigned long start_code, end_code, start_data, end_data;
283 	unsigned long start_brk, brk, start_stack;
284 	unsigned long arg_start, arg_end, env_start, env_end;
285 	unsigned long total_vm, locked_vm, shared_vm;
286 	unsigned long exec_vm, stack_vm, reserved_vm, def_flags, nr_ptes;
287 
288 	/* Special counters protected by the page_table_lock */
289 	mm_counter_t _rss;
290 	mm_counter_t _anon_rss;
291 
292 	unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
293 
294 	unsigned dumpable:2;
295 	cpumask_t cpu_vm_mask;
296 
297 	/* Architecture-specific MM context */
298 	mm_context_t context;
299 
300 	/* Token based thrashing protection. */
301 	unsigned long swap_token_time;
302 	char recent_pagein;
303 
304 	/* coredumping support */
305 	int core_waiters;
306 	struct completion *core_startup_done, core_done;
307 
308 	/* aio bits */
309 	rwlock_t		ioctx_list_lock;
310 	struct kioctx		*ioctx_list;
311 
312 	struct kioctx		default_kioctx;
313 
314 	unsigned long hiwater_rss;	/* High-water RSS usage */
315 	unsigned long hiwater_vm;	/* High-water virtual memory usage */
316 };
317 
318 struct sighand_struct {
319 	atomic_t		count;
320 	struct k_sigaction	action[_NSIG];
321 	spinlock_t		siglock;
322 };
323 
324 /*
325  * NOTE! "signal_struct" does not have it's own
326  * locking, because a shared signal_struct always
327  * implies a shared sighand_struct, so locking
328  * sighand_struct is always a proper superset of
329  * the locking of signal_struct.
330  */
331 struct signal_struct {
332 	atomic_t		count;
333 	atomic_t		live;
334 
335 	wait_queue_head_t	wait_chldexit;	/* for wait4() */
336 
337 	/* current thread group signal load-balancing target: */
338 	task_t			*curr_target;
339 
340 	/* shared signal handling: */
341 	struct sigpending	shared_pending;
342 
343 	/* thread group exit support */
344 	int			group_exit_code;
345 	/* overloaded:
346 	 * - notify group_exit_task when ->count is equal to notify_count
347 	 * - everyone except group_exit_task is stopped during signal delivery
348 	 *   of fatal signals, group_exit_task processes the signal.
349 	 */
350 	struct task_struct	*group_exit_task;
351 	int			notify_count;
352 
353 	/* thread group stop support, overloads group_exit_code too */
354 	int			group_stop_count;
355 	unsigned int		flags; /* see SIGNAL_* flags below */
356 
357 	/* POSIX.1b Interval Timers */
358 	struct list_head posix_timers;
359 
360 	/* ITIMER_REAL timer for the process */
361 	struct timer_list real_timer;
362 	unsigned long it_real_value, it_real_incr;
363 
364 	/* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
365 	cputime_t it_prof_expires, it_virt_expires;
366 	cputime_t it_prof_incr, it_virt_incr;
367 
368 	/* job control IDs */
369 	pid_t pgrp;
370 	pid_t tty_old_pgrp;
371 	pid_t session;
372 	/* boolean value for session group leader */
373 	int leader;
374 
375 	struct tty_struct *tty; /* NULL if no tty */
376 
377 	/*
378 	 * Cumulative resource counters for dead threads in the group,
379 	 * and for reaped dead child processes forked by this group.
380 	 * Live threads maintain their own counters and add to these
381 	 * in __exit_signal, except for the group leader.
382 	 */
383 	cputime_t utime, stime, cutime, cstime;
384 	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
385 	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
386 
387 	/*
388 	 * Cumulative ns of scheduled CPU time for dead threads in the
389 	 * group, not including a zombie group leader.  (This only differs
390 	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
391 	 * other than jiffies.)
392 	 */
393 	unsigned long long sched_time;
394 
395 	/*
396 	 * We don't bother to synchronize most readers of this at all,
397 	 * because there is no reader checking a limit that actually needs
398 	 * to get both rlim_cur and rlim_max atomically, and either one
399 	 * alone is a single word that can safely be read normally.
400 	 * getrlimit/setrlimit use task_lock(current->group_leader) to
401 	 * protect this instead of the siglock, because they really
402 	 * have no need to disable irqs.
403 	 */
404 	struct rlimit rlim[RLIM_NLIMITS];
405 
406 	struct list_head cpu_timers[3];
407 
408 	/* keep the process-shared keyrings here so that they do the right
409 	 * thing in threads created with CLONE_THREAD */
410 #ifdef CONFIG_KEYS
411 	struct key *session_keyring;	/* keyring inherited over fork */
412 	struct key *process_keyring;	/* keyring private to this process */
413 #endif
414 };
415 
416 /* Context switch must be unlocked if interrupts are to be enabled */
417 #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
418 # define __ARCH_WANT_UNLOCKED_CTXSW
419 #endif
420 
421 /*
422  * Bits in flags field of signal_struct.
423  */
424 #define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
425 #define SIGNAL_STOP_DEQUEUED	0x00000002 /* stop signal dequeued */
426 #define SIGNAL_STOP_CONTINUED	0x00000004 /* SIGCONT since WCONTINUED reap */
427 #define SIGNAL_GROUP_EXIT	0x00000008 /* group exit in progress */
428 
429 
430 /*
431  * Priority of a process goes from 0..MAX_PRIO-1, valid RT
432  * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL tasks are
433  * in the range MAX_RT_PRIO..MAX_PRIO-1. Priority values
434  * are inverted: lower p->prio value means higher priority.
435  *
436  * The MAX_USER_RT_PRIO value allows the actual maximum
437  * RT priority to be separate from the value exported to
438  * user-space.  This allows kernel threads to set their
439  * priority to a value higher than any user task. Note:
440  * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
441  */
442 
443 #define MAX_USER_RT_PRIO	100
444 #define MAX_RT_PRIO		MAX_USER_RT_PRIO
445 
446 #define MAX_PRIO		(MAX_RT_PRIO + 40)
447 
448 #define rt_task(p)		(unlikely((p)->prio < MAX_RT_PRIO))
449 
450 /*
451  * Some day this will be a full-fledged user tracking system..
452  */
453 struct user_struct {
454 	atomic_t __count;	/* reference count */
455 	atomic_t processes;	/* How many processes does this user have? */
456 	atomic_t files;		/* How many open files does this user have? */
457 	atomic_t sigpending;	/* How many pending signals does this user have? */
458 #ifdef CONFIG_INOTIFY
459 	atomic_t inotify_watches; /* How many inotify watches does this user have? */
460 	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
461 #endif
462 	/* protected by mq_lock	*/
463 	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
464 	unsigned long locked_shm; /* How many pages of mlocked shm ? */
465 
466 #ifdef CONFIG_KEYS
467 	struct key *uid_keyring;	/* UID specific keyring */
468 	struct key *session_keyring;	/* UID's default session keyring */
469 #endif
470 
471 	/* Hash table maintenance information */
472 	struct list_head uidhash_list;
473 	uid_t uid;
474 };
475 
476 extern struct user_struct *find_user(uid_t);
477 
478 extern struct user_struct root_user;
479 #define INIT_USER (&root_user)
480 
481 typedef struct prio_array prio_array_t;
482 struct backing_dev_info;
483 struct reclaim_state;
484 
485 #ifdef CONFIG_SCHEDSTATS
486 struct sched_info {
487 	/* cumulative counters */
488 	unsigned long	cpu_time,	/* time spent on the cpu */
489 			run_delay,	/* time spent waiting on a runqueue */
490 			pcnt;		/* # of timeslices run on this cpu */
491 
492 	/* timestamps */
493 	unsigned long	last_arrival,	/* when we last ran on a cpu */
494 			last_queued;	/* when we were last queued to run */
495 };
496 
497 extern struct file_operations proc_schedstat_operations;
498 #endif
499 
500 enum idle_type
501 {
502 	SCHED_IDLE,
503 	NOT_IDLE,
504 	NEWLY_IDLE,
505 	MAX_IDLE_TYPES
506 };
507 
508 /*
509  * sched-domains (multiprocessor balancing) declarations:
510  */
511 #ifdef CONFIG_SMP
512 #define SCHED_LOAD_SCALE	128UL	/* increase resolution of load */
513 
514 #define SD_LOAD_BALANCE		1	/* Do load balancing on this domain. */
515 #define SD_BALANCE_NEWIDLE	2	/* Balance when about to become idle */
516 #define SD_BALANCE_EXEC		4	/* Balance on exec */
517 #define SD_BALANCE_FORK		8	/* Balance on fork, clone */
518 #define SD_WAKE_IDLE		16	/* Wake to idle CPU on task wakeup */
519 #define SD_WAKE_AFFINE		32	/* Wake task to waking CPU */
520 #define SD_WAKE_BALANCE		64	/* Perform balancing at task wakeup */
521 #define SD_SHARE_CPUPOWER	128	/* Domain members share cpu power */
522 
523 struct sched_group {
524 	struct sched_group *next;	/* Must be a circular list */
525 	cpumask_t cpumask;
526 
527 	/*
528 	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
529 	 * single CPU. This is read only (except for setup, hotplug CPU).
530 	 */
531 	unsigned long cpu_power;
532 };
533 
534 struct sched_domain {
535 	/* These fields must be setup */
536 	struct sched_domain *parent;	/* top domain must be null terminated */
537 	struct sched_group *groups;	/* the balancing groups of the domain */
538 	cpumask_t span;			/* span of all CPUs in this domain */
539 	unsigned long min_interval;	/* Minimum balance interval ms */
540 	unsigned long max_interval;	/* Maximum balance interval ms */
541 	unsigned int busy_factor;	/* less balancing by factor if busy */
542 	unsigned int imbalance_pct;	/* No balance until over watermark */
543 	unsigned long long cache_hot_time; /* Task considered cache hot (ns) */
544 	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
545 	unsigned int per_cpu_gain;	/* CPU % gained by adding domain cpus */
546 	unsigned int busy_idx;
547 	unsigned int idle_idx;
548 	unsigned int newidle_idx;
549 	unsigned int wake_idx;
550 	unsigned int forkexec_idx;
551 	int flags;			/* See SD_* */
552 
553 	/* Runtime fields. */
554 	unsigned long last_balance;	/* init to jiffies. units in jiffies */
555 	unsigned int balance_interval;	/* initialise to 1. units in ms. */
556 	unsigned int nr_balance_failed; /* initialise to 0 */
557 
558 #ifdef CONFIG_SCHEDSTATS
559 	/* load_balance() stats */
560 	unsigned long lb_cnt[MAX_IDLE_TYPES];
561 	unsigned long lb_failed[MAX_IDLE_TYPES];
562 	unsigned long lb_balanced[MAX_IDLE_TYPES];
563 	unsigned long lb_imbalance[MAX_IDLE_TYPES];
564 	unsigned long lb_gained[MAX_IDLE_TYPES];
565 	unsigned long lb_hot_gained[MAX_IDLE_TYPES];
566 	unsigned long lb_nobusyg[MAX_IDLE_TYPES];
567 	unsigned long lb_nobusyq[MAX_IDLE_TYPES];
568 
569 	/* Active load balancing */
570 	unsigned long alb_cnt;
571 	unsigned long alb_failed;
572 	unsigned long alb_pushed;
573 
574 	/* SD_BALANCE_EXEC stats */
575 	unsigned long sbe_cnt;
576 	unsigned long sbe_balanced;
577 	unsigned long sbe_pushed;
578 
579 	/* SD_BALANCE_FORK stats */
580 	unsigned long sbf_cnt;
581 	unsigned long sbf_balanced;
582 	unsigned long sbf_pushed;
583 
584 	/* try_to_wake_up() stats */
585 	unsigned long ttwu_wake_remote;
586 	unsigned long ttwu_move_affine;
587 	unsigned long ttwu_move_balance;
588 #endif
589 };
590 
591 extern void partition_sched_domains(cpumask_t *partition1,
592 				    cpumask_t *partition2);
593 #endif /* CONFIG_SMP */
594 
595 
596 struct io_context;			/* See blkdev.h */
597 void exit_io_context(void);
598 struct cpuset;
599 
600 #define NGROUPS_SMALL		32
601 #define NGROUPS_PER_BLOCK	((int)(PAGE_SIZE / sizeof(gid_t)))
602 struct group_info {
603 	int ngroups;
604 	atomic_t usage;
605 	gid_t small_block[NGROUPS_SMALL];
606 	int nblocks;
607 	gid_t *blocks[0];
608 };
609 
610 /*
611  * get_group_info() must be called with the owning task locked (via task_lock())
612  * when task != current.  The reason being that the vast majority of callers are
613  * looking at current->group_info, which can not be changed except by the
614  * current task.  Changing current->group_info requires the task lock, too.
615  */
616 #define get_group_info(group_info) do { \
617 	atomic_inc(&(group_info)->usage); \
618 } while (0)
619 
620 #define put_group_info(group_info) do { \
621 	if (atomic_dec_and_test(&(group_info)->usage)) \
622 		groups_free(group_info); \
623 } while (0)
624 
625 extern struct group_info *groups_alloc(int gidsetsize);
626 extern void groups_free(struct group_info *group_info);
627 extern int set_current_groups(struct group_info *group_info);
628 extern int groups_search(struct group_info *group_info, gid_t grp);
629 /* access the groups "array" with this macro */
630 #define GROUP_AT(gi, i) \
631     ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
632 
633 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
634 extern void prefetch_stack(struct task_struct*);
635 #else
636 static inline void prefetch_stack(struct task_struct *t) { }
637 #endif
638 
639 struct audit_context;		/* See audit.c */
640 struct mempolicy;
641 
642 struct task_struct {
643 	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
644 	struct thread_info *thread_info;
645 	atomic_t usage;
646 	unsigned long flags;	/* per process flags, defined below */
647 	unsigned long ptrace;
648 
649 	int lock_depth;		/* BKL lock depth */
650 
651 #if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW)
652 	int oncpu;
653 #endif
654 	int prio, static_prio;
655 	struct list_head run_list;
656 	prio_array_t *array;
657 
658 	unsigned short ioprio;
659 
660 	unsigned long sleep_avg;
661 	unsigned long long timestamp, last_ran;
662 	unsigned long long sched_time; /* sched_clock time spent running */
663 	int activated;
664 
665 	unsigned long policy;
666 	cpumask_t cpus_allowed;
667 	unsigned int time_slice, first_time_slice;
668 
669 #ifdef CONFIG_SCHEDSTATS
670 	struct sched_info sched_info;
671 #endif
672 
673 	struct list_head tasks;
674 	/*
675 	 * ptrace_list/ptrace_children forms the list of my children
676 	 * that were stolen by a ptracer.
677 	 */
678 	struct list_head ptrace_children;
679 	struct list_head ptrace_list;
680 
681 	struct mm_struct *mm, *active_mm;
682 
683 /* task state */
684 	struct linux_binfmt *binfmt;
685 	long exit_state;
686 	int exit_code, exit_signal;
687 	int pdeath_signal;  /*  The signal sent when the parent dies  */
688 	/* ??? */
689 	unsigned long personality;
690 	unsigned did_exec:1;
691 	pid_t pid;
692 	pid_t tgid;
693 	/*
694 	 * pointers to (original) parent process, youngest child, younger sibling,
695 	 * older sibling, respectively.  (p->father can be replaced with
696 	 * p->parent->pid)
697 	 */
698 	struct task_struct *real_parent; /* real parent process (when being debugged) */
699 	struct task_struct *parent;	/* parent process */
700 	/*
701 	 * children/sibling forms the list of my children plus the
702 	 * tasks I'm ptracing.
703 	 */
704 	struct list_head children;	/* list of my children */
705 	struct list_head sibling;	/* linkage in my parent's children list */
706 	struct task_struct *group_leader;	/* threadgroup leader */
707 
708 	/* PID/PID hash table linkage. */
709 	struct pid pids[PIDTYPE_MAX];
710 
711 	struct completion *vfork_done;		/* for vfork() */
712 	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
713 	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
714 
715 	unsigned long rt_priority;
716 	cputime_t utime, stime;
717 	unsigned long nvcsw, nivcsw; /* context switch counts */
718 	struct timespec start_time;
719 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
720 	unsigned long min_flt, maj_flt;
721 
722   	cputime_t it_prof_expires, it_virt_expires;
723 	unsigned long long it_sched_expires;
724 	struct list_head cpu_timers[3];
725 
726 /* process credentials */
727 	uid_t uid,euid,suid,fsuid;
728 	gid_t gid,egid,sgid,fsgid;
729 	struct group_info *group_info;
730 	kernel_cap_t   cap_effective, cap_inheritable, cap_permitted;
731 	unsigned keep_capabilities:1;
732 	struct user_struct *user;
733 #ifdef CONFIG_KEYS
734 	struct key *thread_keyring;	/* keyring private to this thread */
735 	unsigned char jit_keyring;	/* default keyring to attach requested keys to */
736 #endif
737 	int oomkilladj; /* OOM kill score adjustment (bit shift). */
738 	char comm[TASK_COMM_LEN]; /* executable name excluding path
739 				     - access with [gs]et_task_comm (which lock
740 				       it with task_lock())
741 				     - initialized normally by flush_old_exec */
742 /* file system info */
743 	int link_count, total_link_count;
744 /* ipc stuff */
745 	struct sysv_sem sysvsem;
746 /* CPU-specific state of this task */
747 	struct thread_struct thread;
748 /* filesystem information */
749 	struct fs_struct *fs;
750 /* open file information */
751 	struct files_struct *files;
752 /* namespace */
753 	struct namespace *namespace;
754 /* signal handlers */
755 	struct signal_struct *signal;
756 	struct sighand_struct *sighand;
757 
758 	sigset_t blocked, real_blocked;
759 	struct sigpending pending;
760 
761 	unsigned long sas_ss_sp;
762 	size_t sas_ss_size;
763 	int (*notifier)(void *priv);
764 	void *notifier_data;
765 	sigset_t *notifier_mask;
766 
767 	void *security;
768 	struct audit_context *audit_context;
769 	seccomp_t seccomp;
770 
771 /* Thread group tracking */
772    	u32 parent_exec_id;
773    	u32 self_exec_id;
774 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
775 	spinlock_t alloc_lock;
776 /* Protection of proc_dentry: nesting proc_lock, dcache_lock, write_lock_irq(&tasklist_lock); */
777 	spinlock_t proc_lock;
778 
779 /* journalling filesystem info */
780 	void *journal_info;
781 
782 /* VM state */
783 	struct reclaim_state *reclaim_state;
784 
785 	struct dentry *proc_dentry;
786 	struct backing_dev_info *backing_dev_info;
787 
788 	struct io_context *io_context;
789 
790 	unsigned long ptrace_message;
791 	siginfo_t *last_siginfo; /* For ptrace use.  */
792 /*
793  * current io wait handle: wait queue entry to use for io waits
794  * If this thread is processing aio, this points at the waitqueue
795  * inside the currently handled kiocb. It may be NULL (i.e. default
796  * to a stack based synchronous wait) if its doing sync IO.
797  */
798 	wait_queue_t *io_wait;
799 /* i/o counters(bytes read/written, #syscalls */
800 	u64 rchar, wchar, syscr, syscw;
801 #if defined(CONFIG_BSD_PROCESS_ACCT)
802 	u64 acct_rss_mem1;	/* accumulated rss usage */
803 	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
804 	clock_t acct_stimexpd;	/* clock_t-converted stime since last update */
805 #endif
806 #ifdef CONFIG_NUMA
807   	struct mempolicy *mempolicy;
808 	short il_next;
809 #endif
810 #ifdef CONFIG_CPUSETS
811 	struct cpuset *cpuset;
812 	nodemask_t mems_allowed;
813 	int cpuset_mems_generation;
814 #endif
815 	atomic_t fs_excl;	/* holding fs exclusive resources */
816 };
817 
818 static inline pid_t process_group(struct task_struct *tsk)
819 {
820 	return tsk->signal->pgrp;
821 }
822 
823 /**
824  * pid_alive - check that a task structure is not stale
825  * @p: Task structure to be checked.
826  *
827  * Test if a process is not yet dead (at most zombie state)
828  * If pid_alive fails, then pointers within the task structure
829  * can be stale and must not be dereferenced.
830  */
831 static inline int pid_alive(struct task_struct *p)
832 {
833 	return p->pids[PIDTYPE_PID].nr != 0;
834 }
835 
836 extern void free_task(struct task_struct *tsk);
837 extern void __put_task_struct(struct task_struct *tsk);
838 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
839 #define put_task_struct(tsk) \
840 do { if (atomic_dec_and_test(&(tsk)->usage)) __put_task_struct(tsk); } while(0)
841 
842 /*
843  * Per process flags
844  */
845 #define PF_ALIGNWARN	0x00000001	/* Print alignment warning msgs */
846 					/* Not implemented yet, only for 486*/
847 #define PF_STARTING	0x00000002	/* being created */
848 #define PF_EXITING	0x00000004	/* getting shut down */
849 #define PF_DEAD		0x00000008	/* Dead */
850 #define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
851 #define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
852 #define PF_DUMPCORE	0x00000200	/* dumped core */
853 #define PF_SIGNALED	0x00000400	/* killed by a signal */
854 #define PF_MEMALLOC	0x00000800	/* Allocating memory */
855 #define PF_FLUSHER	0x00001000	/* responsible for disk writeback */
856 #define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
857 #define PF_FREEZE	0x00004000	/* this task is being frozen for suspend now */
858 #define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
859 #define PF_FROZEN	0x00010000	/* frozen for system suspend */
860 #define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
861 #define PF_KSWAPD	0x00040000	/* I am kswapd */
862 #define PF_SWAPOFF	0x00080000	/* I am in swapoff */
863 #define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
864 #define PF_SYNCWRITE	0x00200000	/* I am doing a sync write */
865 #define PF_BORROWED_MM	0x00400000	/* I am a kthread doing use_mm */
866 #define PF_RANDOMIZE	0x00800000	/* randomize virtual address space */
867 
868 /*
869  * Only the _current_ task can read/write to tsk->flags, but other
870  * tasks can access tsk->flags in readonly mode for example
871  * with tsk_used_math (like during threaded core dumping).
872  * There is however an exception to this rule during ptrace
873  * or during fork: the ptracer task is allowed to write to the
874  * child->flags of its traced child (same goes for fork, the parent
875  * can write to the child->flags), because we're guaranteed the
876  * child is not running and in turn not changing child->flags
877  * at the same time the parent does it.
878  */
879 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
880 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
881 #define clear_used_math() clear_stopped_child_used_math(current)
882 #define set_used_math() set_stopped_child_used_math(current)
883 #define conditional_stopped_child_used_math(condition, child) \
884 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
885 #define conditional_used_math(condition) \
886 	conditional_stopped_child_used_math(condition, current)
887 #define copy_to_stopped_child_used_math(child) \
888 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
889 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
890 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
891 #define used_math() tsk_used_math(current)
892 
893 #ifdef CONFIG_SMP
894 extern int set_cpus_allowed(task_t *p, cpumask_t new_mask);
895 #else
896 static inline int set_cpus_allowed(task_t *p, cpumask_t new_mask)
897 {
898 	if (!cpus_intersects(new_mask, cpu_online_map))
899 		return -EINVAL;
900 	return 0;
901 }
902 #endif
903 
904 extern unsigned long long sched_clock(void);
905 extern unsigned long long current_sched_time(const task_t *current_task);
906 
907 /* sched_exec is called by processes performing an exec */
908 #ifdef CONFIG_SMP
909 extern void sched_exec(void);
910 #else
911 #define sched_exec()   {}
912 #endif
913 
914 #ifdef CONFIG_HOTPLUG_CPU
915 extern void idle_task_exit(void);
916 #else
917 static inline void idle_task_exit(void) {}
918 #endif
919 
920 extern void sched_idle_next(void);
921 extern void set_user_nice(task_t *p, long nice);
922 extern int task_prio(const task_t *p);
923 extern int task_nice(const task_t *p);
924 extern int can_nice(const task_t *p, const int nice);
925 extern int task_curr(const task_t *p);
926 extern int idle_cpu(int cpu);
927 extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
928 extern task_t *idle_task(int cpu);
929 extern task_t *curr_task(int cpu);
930 extern void set_curr_task(int cpu, task_t *p);
931 
932 void yield(void);
933 
934 /*
935  * The default (Linux) execution domain.
936  */
937 extern struct exec_domain	default_exec_domain;
938 
939 union thread_union {
940 	struct thread_info thread_info;
941 	unsigned long stack[THREAD_SIZE/sizeof(long)];
942 };
943 
944 #ifndef __HAVE_ARCH_KSTACK_END
945 static inline int kstack_end(void *addr)
946 {
947 	/* Reliable end of stack detection:
948 	 * Some APM bios versions misalign the stack
949 	 */
950 	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
951 }
952 #endif
953 
954 extern union thread_union init_thread_union;
955 extern struct task_struct init_task;
956 
957 extern struct   mm_struct init_mm;
958 
959 #define find_task_by_pid(nr)	find_task_by_pid_type(PIDTYPE_PID, nr)
960 extern struct task_struct *find_task_by_pid_type(int type, int pid);
961 extern void set_special_pids(pid_t session, pid_t pgrp);
962 extern void __set_special_pids(pid_t session, pid_t pgrp);
963 
964 /* per-UID process charging. */
965 extern struct user_struct * alloc_uid(uid_t);
966 static inline struct user_struct *get_uid(struct user_struct *u)
967 {
968 	atomic_inc(&u->__count);
969 	return u;
970 }
971 extern void free_uid(struct user_struct *);
972 extern void switch_uid(struct user_struct *);
973 
974 #include <asm/current.h>
975 
976 extern void do_timer(struct pt_regs *);
977 
978 extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state));
979 extern int FASTCALL(wake_up_process(struct task_struct * tsk));
980 extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
981 						unsigned long clone_flags));
982 #ifdef CONFIG_SMP
983  extern void kick_process(struct task_struct *tsk);
984 #else
985  static inline void kick_process(struct task_struct *tsk) { }
986 #endif
987 extern void FASTCALL(sched_fork(task_t * p, int clone_flags));
988 extern void FASTCALL(sched_exit(task_t * p));
989 
990 extern int in_group_p(gid_t);
991 extern int in_egroup_p(gid_t);
992 
993 extern void proc_caches_init(void);
994 extern void flush_signals(struct task_struct *);
995 extern void flush_signal_handlers(struct task_struct *, int force_default);
996 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
997 
998 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
999 {
1000 	unsigned long flags;
1001 	int ret;
1002 
1003 	spin_lock_irqsave(&tsk->sighand->siglock, flags);
1004 	ret = dequeue_signal(tsk, mask, info);
1005 	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1006 
1007 	return ret;
1008 }
1009 
1010 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1011 			      sigset_t *mask);
1012 extern void unblock_all_signals(void);
1013 extern void release_task(struct task_struct * p);
1014 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1015 extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
1016 extern int force_sigsegv(int, struct task_struct *);
1017 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1018 extern int __kill_pg_info(int sig, struct siginfo *info, pid_t pgrp);
1019 extern int kill_pg_info(int, struct siginfo *, pid_t);
1020 extern int kill_proc_info(int, struct siginfo *, pid_t);
1021 extern void do_notify_parent(struct task_struct *, int);
1022 extern void force_sig(int, struct task_struct *);
1023 extern void force_sig_specific(int, struct task_struct *);
1024 extern int send_sig(int, struct task_struct *, int);
1025 extern void zap_other_threads(struct task_struct *p);
1026 extern int kill_pg(pid_t, int, int);
1027 extern int kill_sl(pid_t, int, int);
1028 extern int kill_proc(pid_t, int, int);
1029 extern struct sigqueue *sigqueue_alloc(void);
1030 extern void sigqueue_free(struct sigqueue *);
1031 extern int send_sigqueue(int, struct sigqueue *,  struct task_struct *);
1032 extern int send_group_sigqueue(int, struct sigqueue *,  struct task_struct *);
1033 extern int do_sigaction(int, const struct k_sigaction *, struct k_sigaction *);
1034 extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1035 
1036 /* These can be the second arg to send_sig_info/send_group_sig_info.  */
1037 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
1038 #define SEND_SIG_PRIV	((struct siginfo *) 1)
1039 #define SEND_SIG_FORCED	((struct siginfo *) 2)
1040 
1041 /* True if we are on the alternate signal stack.  */
1042 
1043 static inline int on_sig_stack(unsigned long sp)
1044 {
1045 	return (sp - current->sas_ss_sp < current->sas_ss_size);
1046 }
1047 
1048 static inline int sas_ss_flags(unsigned long sp)
1049 {
1050 	return (current->sas_ss_size == 0 ? SS_DISABLE
1051 		: on_sig_stack(sp) ? SS_ONSTACK : 0);
1052 }
1053 
1054 
1055 #ifdef CONFIG_SECURITY
1056 /* code is in security.c */
1057 extern int capable(int cap);
1058 #else
1059 static inline int capable(int cap)
1060 {
1061 	if (cap_raised(current->cap_effective, cap)) {
1062 		current->flags |= PF_SUPERPRIV;
1063 		return 1;
1064 	}
1065 	return 0;
1066 }
1067 #endif
1068 
1069 /*
1070  * Routines for handling mm_structs
1071  */
1072 extern struct mm_struct * mm_alloc(void);
1073 
1074 /* mmdrop drops the mm and the page tables */
1075 extern void FASTCALL(__mmdrop(struct mm_struct *));
1076 static inline void mmdrop(struct mm_struct * mm)
1077 {
1078 	if (atomic_dec_and_test(&mm->mm_count))
1079 		__mmdrop(mm);
1080 }
1081 
1082 /* mmput gets rid of the mappings and all user-space */
1083 extern void mmput(struct mm_struct *);
1084 /* Grab a reference to a task's mm, if it is not already going away */
1085 extern struct mm_struct *get_task_mm(struct task_struct *task);
1086 /* Remove the current tasks stale references to the old mm_struct */
1087 extern void mm_release(struct task_struct *, struct mm_struct *);
1088 
1089 extern int  copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1090 extern void flush_thread(void);
1091 extern void exit_thread(void);
1092 
1093 extern void exit_files(struct task_struct *);
1094 extern void exit_signal(struct task_struct *);
1095 extern void __exit_signal(struct task_struct *);
1096 extern void exit_sighand(struct task_struct *);
1097 extern void __exit_sighand(struct task_struct *);
1098 extern void exit_itimers(struct signal_struct *);
1099 
1100 extern NORET_TYPE void do_group_exit(int);
1101 
1102 extern void daemonize(const char *, ...);
1103 extern int allow_signal(int);
1104 extern int disallow_signal(int);
1105 extern task_t *child_reaper;
1106 
1107 extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1108 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1109 task_t *fork_idle(int);
1110 
1111 extern void set_task_comm(struct task_struct *tsk, char *from);
1112 extern void get_task_comm(char *to, struct task_struct *tsk);
1113 
1114 #ifdef CONFIG_SMP
1115 extern void wait_task_inactive(task_t * p);
1116 #else
1117 #define wait_task_inactive(p)	do { } while (0)
1118 #endif
1119 
1120 #define remove_parent(p)	list_del_init(&(p)->sibling)
1121 #define add_parent(p, parent)	list_add_tail(&(p)->sibling,&(parent)->children)
1122 
1123 #define REMOVE_LINKS(p) do {					\
1124 	if (thread_group_leader(p))				\
1125 		list_del_init(&(p)->tasks);			\
1126 	remove_parent(p);					\
1127 	} while (0)
1128 
1129 #define SET_LINKS(p) do {					\
1130 	if (thread_group_leader(p))				\
1131 		list_add_tail(&(p)->tasks,&init_task.tasks);	\
1132 	add_parent(p, (p)->parent);				\
1133 	} while (0)
1134 
1135 #define next_task(p)	list_entry((p)->tasks.next, struct task_struct, tasks)
1136 #define prev_task(p)	list_entry((p)->tasks.prev, struct task_struct, tasks)
1137 
1138 #define for_each_process(p) \
1139 	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1140 
1141 /*
1142  * Careful: do_each_thread/while_each_thread is a double loop so
1143  *          'break' will not work as expected - use goto instead.
1144  */
1145 #define do_each_thread(g, t) \
1146 	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1147 
1148 #define while_each_thread(g, t) \
1149 	while ((t = next_thread(t)) != g)
1150 
1151 extern task_t * FASTCALL(next_thread(const task_t *p));
1152 
1153 #define thread_group_leader(p)	(p->pid == p->tgid)
1154 
1155 static inline int thread_group_empty(task_t *p)
1156 {
1157 	return list_empty(&p->pids[PIDTYPE_TGID].pid_list);
1158 }
1159 
1160 #define delay_group_leader(p) \
1161 		(thread_group_leader(p) && !thread_group_empty(p))
1162 
1163 extern void unhash_process(struct task_struct *p);
1164 
1165 /*
1166  * Protects ->fs, ->files, ->mm, ->ptrace, ->group_info, ->comm, keyring
1167  * subscriptions and synchronises with wait4().  Also used in procfs.  Also
1168  * pins the final release of task.io_context.
1169  *
1170  * Nests both inside and outside of read_lock(&tasklist_lock).
1171  * It must not be nested with write_lock_irq(&tasklist_lock),
1172  * neither inside nor outside.
1173  */
1174 static inline void task_lock(struct task_struct *p)
1175 {
1176 	spin_lock(&p->alloc_lock);
1177 }
1178 
1179 static inline void task_unlock(struct task_struct *p)
1180 {
1181 	spin_unlock(&p->alloc_lock);
1182 }
1183 
1184 /* set thread flags in other task's structures
1185  * - see asm/thread_info.h for TIF_xxxx flags available
1186  */
1187 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1188 {
1189 	set_ti_thread_flag(tsk->thread_info,flag);
1190 }
1191 
1192 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1193 {
1194 	clear_ti_thread_flag(tsk->thread_info,flag);
1195 }
1196 
1197 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1198 {
1199 	return test_and_set_ti_thread_flag(tsk->thread_info,flag);
1200 }
1201 
1202 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1203 {
1204 	return test_and_clear_ti_thread_flag(tsk->thread_info,flag);
1205 }
1206 
1207 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1208 {
1209 	return test_ti_thread_flag(tsk->thread_info,flag);
1210 }
1211 
1212 static inline void set_tsk_need_resched(struct task_struct *tsk)
1213 {
1214 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1215 }
1216 
1217 static inline void clear_tsk_need_resched(struct task_struct *tsk)
1218 {
1219 	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1220 }
1221 
1222 static inline int signal_pending(struct task_struct *p)
1223 {
1224 	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1225 }
1226 
1227 static inline int need_resched(void)
1228 {
1229 	return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1230 }
1231 
1232 /*
1233  * cond_resched() and cond_resched_lock(): latency reduction via
1234  * explicit rescheduling in places that are safe. The return
1235  * value indicates whether a reschedule was done in fact.
1236  * cond_resched_lock() will drop the spinlock before scheduling,
1237  * cond_resched_softirq() will enable bhs before scheduling.
1238  */
1239 extern int cond_resched(void);
1240 extern int cond_resched_lock(spinlock_t * lock);
1241 extern int cond_resched_softirq(void);
1242 
1243 /*
1244  * Does a critical section need to be broken due to another
1245  * task waiting?:
1246  */
1247 #if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
1248 # define need_lockbreak(lock) ((lock)->break_lock)
1249 #else
1250 # define need_lockbreak(lock) 0
1251 #endif
1252 
1253 /*
1254  * Does a critical section need to be broken due to another
1255  * task waiting or preemption being signalled:
1256  */
1257 static inline int lock_need_resched(spinlock_t *lock)
1258 {
1259 	if (need_lockbreak(lock) || need_resched())
1260 		return 1;
1261 	return 0;
1262 }
1263 
1264 /* Reevaluate whether the task has signals pending delivery.
1265    This is required every time the blocked sigset_t changes.
1266    callers must hold sighand->siglock.  */
1267 
1268 extern FASTCALL(void recalc_sigpending_tsk(struct task_struct *t));
1269 extern void recalc_sigpending(void);
1270 
1271 extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1272 
1273 /*
1274  * Wrappers for p->thread_info->cpu access. No-op on UP.
1275  */
1276 #ifdef CONFIG_SMP
1277 
1278 static inline unsigned int task_cpu(const struct task_struct *p)
1279 {
1280 	return p->thread_info->cpu;
1281 }
1282 
1283 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1284 {
1285 	p->thread_info->cpu = cpu;
1286 }
1287 
1288 #else
1289 
1290 static inline unsigned int task_cpu(const struct task_struct *p)
1291 {
1292 	return 0;
1293 }
1294 
1295 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1296 {
1297 }
1298 
1299 #endif /* CONFIG_SMP */
1300 
1301 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1302 extern void arch_pick_mmap_layout(struct mm_struct *mm);
1303 #else
1304 static inline void arch_pick_mmap_layout(struct mm_struct *mm)
1305 {
1306 	mm->mmap_base = TASK_UNMAPPED_BASE;
1307 	mm->get_unmapped_area = arch_get_unmapped_area;
1308 	mm->unmap_area = arch_unmap_area;
1309 }
1310 #endif
1311 
1312 extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
1313 extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
1314 
1315 #ifdef CONFIG_MAGIC_SYSRQ
1316 
1317 extern void normalize_rt_tasks(void);
1318 
1319 #endif
1320 
1321 #ifdef CONFIG_PM
1322 /*
1323  * Check if a process has been frozen
1324  */
1325 static inline int frozen(struct task_struct *p)
1326 {
1327 	return p->flags & PF_FROZEN;
1328 }
1329 
1330 /*
1331  * Check if there is a request to freeze a process
1332  */
1333 static inline int freezing(struct task_struct *p)
1334 {
1335 	return p->flags & PF_FREEZE;
1336 }
1337 
1338 /*
1339  * Request that a process be frozen
1340  * FIXME: SMP problem. We may not modify other process' flags!
1341  */
1342 static inline void freeze(struct task_struct *p)
1343 {
1344 	p->flags |= PF_FREEZE;
1345 }
1346 
1347 /*
1348  * Wake up a frozen process
1349  */
1350 static inline int thaw_process(struct task_struct *p)
1351 {
1352 	if (frozen(p)) {
1353 		p->flags &= ~PF_FROZEN;
1354 		wake_up_process(p);
1355 		return 1;
1356 	}
1357 	return 0;
1358 }
1359 
1360 /*
1361  * freezing is complete, mark process as frozen
1362  */
1363 static inline void frozen_process(struct task_struct *p)
1364 {
1365 	p->flags = (p->flags & ~PF_FREEZE) | PF_FROZEN;
1366 }
1367 
1368 extern void refrigerator(void);
1369 extern int freeze_processes(void);
1370 extern void thaw_processes(void);
1371 
1372 static inline int try_to_freeze(void)
1373 {
1374 	if (freezing(current)) {
1375 		refrigerator();
1376 		return 1;
1377 	} else
1378 		return 0;
1379 }
1380 #else
1381 static inline int frozen(struct task_struct *p) { return 0; }
1382 static inline int freezing(struct task_struct *p) { return 0; }
1383 static inline void freeze(struct task_struct *p) { BUG(); }
1384 static inline int thaw_process(struct task_struct *p) { return 1; }
1385 static inline void frozen_process(struct task_struct *p) { BUG(); }
1386 
1387 static inline void refrigerator(void) {}
1388 static inline int freeze_processes(void) { BUG(); return 0; }
1389 static inline void thaw_processes(void) {}
1390 
1391 static inline int try_to_freeze(void) { return 0; }
1392 
1393 #endif /* CONFIG_PM */
1394 #endif /* __KERNEL__ */
1395 
1396 #endif
1397