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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 struct task_struct;
188 
189 extern void sched_init(void);
190 extern void sched_init_smp(void);
191 extern void init_idle(struct task_struct *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
softlockup_tick(void)218 static inline void softlockup_tick(void)
219 {
220 }
spawn_softlockup_task(void)221 static inline void spawn_softlockup_task(void)
222 {
223 }
touch_softlockup_watchdog(void)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 	struct task_struct	*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 #ifdef CONFIG_TASKSTATS
467 	spinlock_t stats_lock;
468 	struct taskstats *stats;
469 #endif
470 };
471 
472 /* Context switch must be unlocked if interrupts are to be enabled */
473 #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
474 # define __ARCH_WANT_UNLOCKED_CTXSW
475 #endif
476 
477 /*
478  * Bits in flags field of signal_struct.
479  */
480 #define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
481 #define SIGNAL_STOP_DEQUEUED	0x00000002 /* stop signal dequeued */
482 #define SIGNAL_STOP_CONTINUED	0x00000004 /* SIGCONT since WCONTINUED reap */
483 #define SIGNAL_GROUP_EXIT	0x00000008 /* group exit in progress */
484 
485 
486 /*
487  * Priority of a process goes from 0..MAX_PRIO-1, valid RT
488  * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
489  * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
490  * values are inverted: lower p->prio value means higher priority.
491  *
492  * The MAX_USER_RT_PRIO value allows the actual maximum
493  * RT priority to be separate from the value exported to
494  * user-space.  This allows kernel threads to set their
495  * priority to a value higher than any user task. Note:
496  * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
497  */
498 
499 #define MAX_USER_RT_PRIO	100
500 #define MAX_RT_PRIO		MAX_USER_RT_PRIO
501 
502 #define MAX_PRIO		(MAX_RT_PRIO + 40)
503 
504 #define rt_prio(prio)		unlikely((prio) < MAX_RT_PRIO)
505 #define rt_task(p)		rt_prio((p)->prio)
506 #define batch_task(p)		(unlikely((p)->policy == SCHED_BATCH))
507 #define has_rt_policy(p) \
508 	unlikely((p)->policy != SCHED_NORMAL && (p)->policy != SCHED_BATCH)
509 
510 /*
511  * Some day this will be a full-fledged user tracking system..
512  */
513 struct user_struct {
514 	atomic_t __count;	/* reference count */
515 	atomic_t processes;	/* How many processes does this user have? */
516 	atomic_t files;		/* How many open files does this user have? */
517 	atomic_t sigpending;	/* How many pending signals does this user have? */
518 #ifdef CONFIG_INOTIFY_USER
519 	atomic_t inotify_watches; /* How many inotify watches does this user have? */
520 	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
521 #endif
522 	/* protected by mq_lock	*/
523 	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
524 	unsigned long locked_shm; /* How many pages of mlocked shm ? */
525 
526 #ifdef CONFIG_KEYS
527 	struct key *uid_keyring;	/* UID specific keyring */
528 	struct key *session_keyring;	/* UID's default session keyring */
529 #endif
530 
531 	/* Hash table maintenance information */
532 	struct list_head uidhash_list;
533 	uid_t uid;
534 };
535 
536 extern struct user_struct *find_user(uid_t);
537 
538 extern struct user_struct root_user;
539 #define INIT_USER (&root_user)
540 
541 struct backing_dev_info;
542 struct reclaim_state;
543 
544 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
545 struct sched_info {
546 	/* cumulative counters */
547 	unsigned long	cpu_time,	/* time spent on the cpu */
548 			run_delay,	/* time spent waiting on a runqueue */
549 			pcnt;		/* # of timeslices run on this cpu */
550 
551 	/* timestamps */
552 	unsigned long	last_arrival,	/* when we last ran on a cpu */
553 			last_queued;	/* when we were last queued to run */
554 };
555 #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
556 
557 #ifdef CONFIG_SCHEDSTATS
558 extern struct file_operations proc_schedstat_operations;
559 #endif /* CONFIG_SCHEDSTATS */
560 
561 #ifdef CONFIG_TASK_DELAY_ACCT
562 struct task_delay_info {
563 	spinlock_t	lock;
564 	unsigned int	flags;	/* Private per-task flags */
565 
566 	/* For each stat XXX, add following, aligned appropriately
567 	 *
568 	 * struct timespec XXX_start, XXX_end;
569 	 * u64 XXX_delay;
570 	 * u32 XXX_count;
571 	 *
572 	 * Atomicity of updates to XXX_delay, XXX_count protected by
573 	 * single lock above (split into XXX_lock if contention is an issue).
574 	 */
575 
576 	/*
577 	 * XXX_count is incremented on every XXX operation, the delay
578 	 * associated with the operation is added to XXX_delay.
579 	 * XXX_delay contains the accumulated delay time in nanoseconds.
580 	 */
581 	struct timespec blkio_start, blkio_end;	/* Shared by blkio, swapin */
582 	u64 blkio_delay;	/* wait for sync block io completion */
583 	u64 swapin_delay;	/* wait for swapin block io completion */
584 	u32 blkio_count;	/* total count of the number of sync block */
585 				/* io operations performed */
586 	u32 swapin_count;	/* total count of the number of swapin block */
587 				/* io operations performed */
588 };
589 #endif	/* CONFIG_TASK_DELAY_ACCT */
590 
sched_info_on(void)591 static inline int sched_info_on(void)
592 {
593 #ifdef CONFIG_SCHEDSTATS
594 	return 1;
595 #elif defined(CONFIG_TASK_DELAY_ACCT)
596 	extern int delayacct_on;
597 	return delayacct_on;
598 #else
599 	return 0;
600 #endif
601 }
602 
603 enum idle_type
604 {
605 	SCHED_IDLE,
606 	NOT_IDLE,
607 	NEWLY_IDLE,
608 	MAX_IDLE_TYPES
609 };
610 
611 /*
612  * sched-domains (multiprocessor balancing) declarations:
613  */
614 #define SCHED_LOAD_SCALE	128UL	/* increase resolution of load */
615 
616 #ifdef CONFIG_SMP
617 #define SD_LOAD_BALANCE		1	/* Do load balancing on this domain. */
618 #define SD_BALANCE_NEWIDLE	2	/* Balance when about to become idle */
619 #define SD_BALANCE_EXEC		4	/* Balance on exec */
620 #define SD_BALANCE_FORK		8	/* Balance on fork, clone */
621 #define SD_WAKE_IDLE		16	/* Wake to idle CPU on task wakeup */
622 #define SD_WAKE_AFFINE		32	/* Wake task to waking CPU */
623 #define SD_WAKE_BALANCE		64	/* Perform balancing at task wakeup */
624 #define SD_SHARE_CPUPOWER	128	/* Domain members share cpu power */
625 #define SD_POWERSAVINGS_BALANCE	256	/* Balance for power savings */
626 
627 #define BALANCE_FOR_POWER	((sched_mc_power_savings || sched_smt_power_savings) \
628 				 ? SD_POWERSAVINGS_BALANCE : 0)
629 
630 
631 struct sched_group {
632 	struct sched_group *next;	/* Must be a circular list */
633 	cpumask_t cpumask;
634 
635 	/*
636 	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
637 	 * single CPU. This is read only (except for setup, hotplug CPU).
638 	 */
639 	unsigned long cpu_power;
640 };
641 
642 struct sched_domain {
643 	/* These fields must be setup */
644 	struct sched_domain *parent;	/* top domain must be null terminated */
645 	struct sched_group *groups;	/* the balancing groups of the domain */
646 	cpumask_t span;			/* span of all CPUs in this domain */
647 	unsigned long min_interval;	/* Minimum balance interval ms */
648 	unsigned long max_interval;	/* Maximum balance interval ms */
649 	unsigned int busy_factor;	/* less balancing by factor if busy */
650 	unsigned int imbalance_pct;	/* No balance until over watermark */
651 	unsigned long long cache_hot_time; /* Task considered cache hot (ns) */
652 	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
653 	unsigned int per_cpu_gain;	/* CPU % gained by adding domain cpus */
654 	unsigned int busy_idx;
655 	unsigned int idle_idx;
656 	unsigned int newidle_idx;
657 	unsigned int wake_idx;
658 	unsigned int forkexec_idx;
659 	int flags;			/* See SD_* */
660 
661 	/* Runtime fields. */
662 	unsigned long last_balance;	/* init to jiffies. units in jiffies */
663 	unsigned int balance_interval;	/* initialise to 1. units in ms. */
664 	unsigned int nr_balance_failed; /* initialise to 0 */
665 
666 #ifdef CONFIG_SCHEDSTATS
667 	/* load_balance() stats */
668 	unsigned long lb_cnt[MAX_IDLE_TYPES];
669 	unsigned long lb_failed[MAX_IDLE_TYPES];
670 	unsigned long lb_balanced[MAX_IDLE_TYPES];
671 	unsigned long lb_imbalance[MAX_IDLE_TYPES];
672 	unsigned long lb_gained[MAX_IDLE_TYPES];
673 	unsigned long lb_hot_gained[MAX_IDLE_TYPES];
674 	unsigned long lb_nobusyg[MAX_IDLE_TYPES];
675 	unsigned long lb_nobusyq[MAX_IDLE_TYPES];
676 
677 	/* Active load balancing */
678 	unsigned long alb_cnt;
679 	unsigned long alb_failed;
680 	unsigned long alb_pushed;
681 
682 	/* SD_BALANCE_EXEC stats */
683 	unsigned long sbe_cnt;
684 	unsigned long sbe_balanced;
685 	unsigned long sbe_pushed;
686 
687 	/* SD_BALANCE_FORK stats */
688 	unsigned long sbf_cnt;
689 	unsigned long sbf_balanced;
690 	unsigned long sbf_pushed;
691 
692 	/* try_to_wake_up() stats */
693 	unsigned long ttwu_wake_remote;
694 	unsigned long ttwu_move_affine;
695 	unsigned long ttwu_move_balance;
696 #endif
697 };
698 
699 extern int partition_sched_domains(cpumask_t *partition1,
700 				    cpumask_t *partition2);
701 
702 /*
703  * Maximum cache size the migration-costs auto-tuning code will
704  * search from:
705  */
706 extern unsigned int max_cache_size;
707 
708 #endif	/* CONFIG_SMP */
709 
710 
711 struct io_context;			/* See blkdev.h */
712 void exit_io_context(void);
713 struct cpuset;
714 
715 #define NGROUPS_SMALL		32
716 #define NGROUPS_PER_BLOCK	((int)(PAGE_SIZE / sizeof(gid_t)))
717 struct group_info {
718 	int ngroups;
719 	atomic_t usage;
720 	gid_t small_block[NGROUPS_SMALL];
721 	int nblocks;
722 	gid_t *blocks[0];
723 };
724 
725 /*
726  * get_group_info() must be called with the owning task locked (via task_lock())
727  * when task != current.  The reason being that the vast majority of callers are
728  * looking at current->group_info, which can not be changed except by the
729  * current task.  Changing current->group_info requires the task lock, too.
730  */
731 #define get_group_info(group_info) do { \
732 	atomic_inc(&(group_info)->usage); \
733 } while (0)
734 
735 #define put_group_info(group_info) do { \
736 	if (atomic_dec_and_test(&(group_info)->usage)) \
737 		groups_free(group_info); \
738 } while (0)
739 
740 extern struct group_info *groups_alloc(int gidsetsize);
741 extern void groups_free(struct group_info *group_info);
742 extern int set_current_groups(struct group_info *group_info);
743 extern int groups_search(struct group_info *group_info, gid_t grp);
744 /* access the groups "array" with this macro */
745 #define GROUP_AT(gi, i) \
746     ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
747 
748 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
749 extern void prefetch_stack(struct task_struct *t);
750 #else
prefetch_stack(struct task_struct * t)751 static inline void prefetch_stack(struct task_struct *t) { }
752 #endif
753 
754 struct audit_context;		/* See audit.c */
755 struct mempolicy;
756 struct pipe_inode_info;
757 
758 enum sleep_type {
759 	SLEEP_NORMAL,
760 	SLEEP_NONINTERACTIVE,
761 	SLEEP_INTERACTIVE,
762 	SLEEP_INTERRUPTED,
763 };
764 
765 struct prio_array;
766 
767 struct task_struct {
768 	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
769 	struct thread_info *thread_info;
770 	atomic_t usage;
771 	unsigned long flags;	/* per process flags, defined below */
772 	unsigned long ptrace;
773 
774 	int lock_depth;		/* BKL lock depth */
775 
776 #ifdef CONFIG_SMP
777 #ifdef __ARCH_WANT_UNLOCKED_CTXSW
778 	int oncpu;
779 #endif
780 #endif
781 	int load_weight;	/* for niceness load balancing purposes */
782 	int prio, static_prio, normal_prio;
783 	struct list_head run_list;
784 	struct prio_array *array;
785 
786 	unsigned short ioprio;
787 	unsigned int btrace_seq;
788 
789 	unsigned long sleep_avg;
790 	unsigned long long timestamp, last_ran;
791 	unsigned long long sched_time; /* sched_clock time spent running */
792 	enum sleep_type sleep_type;
793 
794 	unsigned long policy;
795 	cpumask_t cpus_allowed;
796 	unsigned int time_slice, first_time_slice;
797 
798 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
799 	struct sched_info sched_info;
800 #endif
801 
802 	struct list_head tasks;
803 	/*
804 	 * ptrace_list/ptrace_children forms the list of my children
805 	 * that were stolen by a ptracer.
806 	 */
807 	struct list_head ptrace_children;
808 	struct list_head ptrace_list;
809 
810 	struct mm_struct *mm, *active_mm;
811 
812 /* task state */
813 	struct linux_binfmt *binfmt;
814 	long exit_state;
815 	int exit_code, exit_signal;
816 	int pdeath_signal;  /*  The signal sent when the parent dies  */
817 	/* ??? */
818 	unsigned long personality;
819 	unsigned did_exec:1;
820 	pid_t pid;
821 	pid_t tgid;
822 	/*
823 	 * pointers to (original) parent process, youngest child, younger sibling,
824 	 * older sibling, respectively.  (p->father can be replaced with
825 	 * p->parent->pid)
826 	 */
827 	struct task_struct *real_parent; /* real parent process (when being debugged) */
828 	struct task_struct *parent;	/* parent process */
829 	/*
830 	 * children/sibling forms the list of my children plus the
831 	 * tasks I'm ptracing.
832 	 */
833 	struct list_head children;	/* list of my children */
834 	struct list_head sibling;	/* linkage in my parent's children list */
835 	struct task_struct *group_leader;	/* threadgroup leader */
836 
837 	/* PID/PID hash table linkage. */
838 	struct pid_link pids[PIDTYPE_MAX];
839 	struct list_head thread_group;
840 
841 	struct completion *vfork_done;		/* for vfork() */
842 	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
843 	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
844 
845 	unsigned long rt_priority;
846 	cputime_t utime, stime;
847 	unsigned long nvcsw, nivcsw; /* context switch counts */
848 	struct timespec start_time;
849 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
850 	unsigned long min_flt, maj_flt;
851 
852   	cputime_t it_prof_expires, it_virt_expires;
853 	unsigned long long it_sched_expires;
854 	struct list_head cpu_timers[3];
855 
856 /* process credentials */
857 	uid_t uid,euid,suid,fsuid;
858 	gid_t gid,egid,sgid,fsgid;
859 	struct group_info *group_info;
860 	kernel_cap_t   cap_effective, cap_inheritable, cap_permitted;
861 	unsigned keep_capabilities:1;
862 	struct user_struct *user;
863 #ifdef CONFIG_KEYS
864 	struct key *request_key_auth;	/* assumed request_key authority */
865 	struct key *thread_keyring;	/* keyring private to this thread */
866 	unsigned char jit_keyring;	/* default keyring to attach requested keys to */
867 #endif
868 	int oomkilladj; /* OOM kill score adjustment (bit shift). */
869 	char comm[TASK_COMM_LEN]; /* executable name excluding path
870 				     - access with [gs]et_task_comm (which lock
871 				       it with task_lock())
872 				     - initialized normally by flush_old_exec */
873 /* file system info */
874 	int link_count, total_link_count;
875 /* ipc stuff */
876 	struct sysv_sem sysvsem;
877 /* CPU-specific state of this task */
878 	struct thread_struct thread;
879 /* filesystem information */
880 	struct fs_struct *fs;
881 /* open file information */
882 	struct files_struct *files;
883 /* namespace */
884 	struct namespace *namespace;
885 /* signal handlers */
886 	struct signal_struct *signal;
887 	struct sighand_struct *sighand;
888 
889 	sigset_t blocked, real_blocked;
890 	sigset_t saved_sigmask;		/* To be restored with TIF_RESTORE_SIGMASK */
891 	struct sigpending pending;
892 
893 	unsigned long sas_ss_sp;
894 	size_t sas_ss_size;
895 	int (*notifier)(void *priv);
896 	void *notifier_data;
897 	sigset_t *notifier_mask;
898 
899 	void *security;
900 	struct audit_context *audit_context;
901 	seccomp_t seccomp;
902 
903 /* Thread group tracking */
904    	u32 parent_exec_id;
905    	u32 self_exec_id;
906 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
907 	spinlock_t alloc_lock;
908 
909 	/* Protection of the PI data structures: */
910 	spinlock_t pi_lock;
911 
912 #ifdef CONFIG_RT_MUTEXES
913 	/* PI waiters blocked on a rt_mutex held by this task */
914 	struct plist_head pi_waiters;
915 	/* Deadlock detection and priority inheritance handling */
916 	struct rt_mutex_waiter *pi_blocked_on;
917 #endif
918 
919 #ifdef CONFIG_DEBUG_MUTEXES
920 	/* mutex deadlock detection */
921 	struct mutex_waiter *blocked_on;
922 #endif
923 #ifdef CONFIG_TRACE_IRQFLAGS
924 	unsigned int irq_events;
925 	int hardirqs_enabled;
926 	unsigned long hardirq_enable_ip;
927 	unsigned int hardirq_enable_event;
928 	unsigned long hardirq_disable_ip;
929 	unsigned int hardirq_disable_event;
930 	int softirqs_enabled;
931 	unsigned long softirq_disable_ip;
932 	unsigned int softirq_disable_event;
933 	unsigned long softirq_enable_ip;
934 	unsigned int softirq_enable_event;
935 	int hardirq_context;
936 	int softirq_context;
937 #endif
938 #ifdef CONFIG_LOCKDEP
939 # define MAX_LOCK_DEPTH 30UL
940 	u64 curr_chain_key;
941 	int lockdep_depth;
942 	struct held_lock held_locks[MAX_LOCK_DEPTH];
943 	unsigned int lockdep_recursion;
944 #endif
945 
946 /* journalling filesystem info */
947 	void *journal_info;
948 
949 /* VM state */
950 	struct reclaim_state *reclaim_state;
951 
952 	struct backing_dev_info *backing_dev_info;
953 
954 	struct io_context *io_context;
955 
956 	unsigned long ptrace_message;
957 	siginfo_t *last_siginfo; /* For ptrace use.  */
958 /*
959  * current io wait handle: wait queue entry to use for io waits
960  * If this thread is processing aio, this points at the waitqueue
961  * inside the currently handled kiocb. It may be NULL (i.e. default
962  * to a stack based synchronous wait) if its doing sync IO.
963  */
964 	wait_queue_t *io_wait;
965 /* i/o counters(bytes read/written, #syscalls */
966 	u64 rchar, wchar, syscr, syscw;
967 #if defined(CONFIG_BSD_PROCESS_ACCT)
968 	u64 acct_rss_mem1;	/* accumulated rss usage */
969 	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
970 	clock_t acct_stimexpd;	/* clock_t-converted stime since last update */
971 #endif
972 #ifdef CONFIG_NUMA
973   	struct mempolicy *mempolicy;
974 	short il_next;
975 #endif
976 #ifdef CONFIG_CPUSETS
977 	struct cpuset *cpuset;
978 	nodemask_t mems_allowed;
979 	int cpuset_mems_generation;
980 	int cpuset_mem_spread_rotor;
981 #endif
982 	struct robust_list_head __user *robust_list;
983 #ifdef CONFIG_COMPAT
984 	struct compat_robust_list_head __user *compat_robust_list;
985 #endif
986 	struct list_head pi_state_list;
987 	struct futex_pi_state *pi_state_cache;
988 
989 	atomic_t fs_excl;	/* holding fs exclusive resources */
990 	struct rcu_head rcu;
991 
992 	/*
993 	 * cache last used pipe for splice
994 	 */
995 	struct pipe_inode_info *splice_pipe;
996 #ifdef	CONFIG_TASK_DELAY_ACCT
997 	struct task_delay_info *delays;
998 #endif
999 };
1000 
process_group(struct task_struct * tsk)1001 static inline pid_t process_group(struct task_struct *tsk)
1002 {
1003 	return tsk->signal->pgrp;
1004 }
1005 
1006 /**
1007  * pid_alive - check that a task structure is not stale
1008  * @p: Task structure to be checked.
1009  *
1010  * Test if a process is not yet dead (at most zombie state)
1011  * If pid_alive fails, then pointers within the task structure
1012  * can be stale and must not be dereferenced.
1013  */
pid_alive(struct task_struct * p)1014 static inline int pid_alive(struct task_struct *p)
1015 {
1016 	return p->pids[PIDTYPE_PID].pid != NULL;
1017 }
1018 
1019 extern void free_task(struct task_struct *tsk);
1020 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1021 
1022 extern void __put_task_struct(struct task_struct *t);
1023 
put_task_struct(struct task_struct * t)1024 static inline void put_task_struct(struct task_struct *t)
1025 {
1026 	if (atomic_dec_and_test(&t->usage))
1027 		__put_task_struct(t);
1028 }
1029 
1030 /*
1031  * Per process flags
1032  */
1033 #define PF_ALIGNWARN	0x00000001	/* Print alignment warning msgs */
1034 					/* Not implemented yet, only for 486*/
1035 #define PF_STARTING	0x00000002	/* being created */
1036 #define PF_EXITING	0x00000004	/* getting shut down */
1037 #define PF_DEAD		0x00000008	/* Dead */
1038 #define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
1039 #define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
1040 #define PF_DUMPCORE	0x00000200	/* dumped core */
1041 #define PF_SIGNALED	0x00000400	/* killed by a signal */
1042 #define PF_MEMALLOC	0x00000800	/* Allocating memory */
1043 #define PF_FLUSHER	0x00001000	/* responsible for disk writeback */
1044 #define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
1045 #define PF_FREEZE	0x00004000	/* this task is being frozen for suspend now */
1046 #define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
1047 #define PF_FROZEN	0x00010000	/* frozen for system suspend */
1048 #define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
1049 #define PF_KSWAPD	0x00040000	/* I am kswapd */
1050 #define PF_SWAPOFF	0x00080000	/* I am in swapoff */
1051 #define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
1052 #define PF_BORROWED_MM	0x00200000	/* I am a kthread doing use_mm */
1053 #define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
1054 #define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
1055 #define PF_SPREAD_PAGE	0x01000000	/* Spread page cache over cpuset */
1056 #define PF_SPREAD_SLAB	0x02000000	/* Spread some slab caches over cpuset */
1057 #define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
1058 #define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
1059 
1060 /*
1061  * Only the _current_ task can read/write to tsk->flags, but other
1062  * tasks can access tsk->flags in readonly mode for example
1063  * with tsk_used_math (like during threaded core dumping).
1064  * There is however an exception to this rule during ptrace
1065  * or during fork: the ptracer task is allowed to write to the
1066  * child->flags of its traced child (same goes for fork, the parent
1067  * can write to the child->flags), because we're guaranteed the
1068  * child is not running and in turn not changing child->flags
1069  * at the same time the parent does it.
1070  */
1071 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1072 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1073 #define clear_used_math() clear_stopped_child_used_math(current)
1074 #define set_used_math() set_stopped_child_used_math(current)
1075 #define conditional_stopped_child_used_math(condition, child) \
1076 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1077 #define conditional_used_math(condition) \
1078 	conditional_stopped_child_used_math(condition, current)
1079 #define copy_to_stopped_child_used_math(child) \
1080 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1081 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1082 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1083 #define used_math() tsk_used_math(current)
1084 
1085 #ifdef CONFIG_SMP
1086 extern int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask);
1087 #else
set_cpus_allowed(struct task_struct * p,cpumask_t new_mask)1088 static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1089 {
1090 	if (!cpu_isset(0, new_mask))
1091 		return -EINVAL;
1092 	return 0;
1093 }
1094 #endif
1095 
1096 extern unsigned long long sched_clock(void);
1097 extern unsigned long long
1098 current_sched_time(const struct task_struct *current_task);
1099 
1100 /* sched_exec is called by processes performing an exec */
1101 #ifdef CONFIG_SMP
1102 extern void sched_exec(void);
1103 #else
1104 #define sched_exec()   {}
1105 #endif
1106 
1107 #ifdef CONFIG_HOTPLUG_CPU
1108 extern void idle_task_exit(void);
1109 #else
idle_task_exit(void)1110 static inline void idle_task_exit(void) {}
1111 #endif
1112 
1113 extern void sched_idle_next(void);
1114 
1115 #ifdef CONFIG_RT_MUTEXES
1116 extern int rt_mutex_getprio(struct task_struct *p);
1117 extern void rt_mutex_setprio(struct task_struct *p, int prio);
1118 extern void rt_mutex_adjust_pi(struct task_struct *p);
1119 #else
rt_mutex_getprio(struct task_struct * p)1120 static inline int rt_mutex_getprio(struct task_struct *p)
1121 {
1122 	return p->normal_prio;
1123 }
1124 # define rt_mutex_adjust_pi(p)		do { } while (0)
1125 #endif
1126 
1127 extern void set_user_nice(struct task_struct *p, long nice);
1128 extern int task_prio(const struct task_struct *p);
1129 extern int task_nice(const struct task_struct *p);
1130 extern int can_nice(const struct task_struct *p, const int nice);
1131 extern int task_curr(const struct task_struct *p);
1132 extern int idle_cpu(int cpu);
1133 extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1134 extern struct task_struct *idle_task(int cpu);
1135 extern struct task_struct *curr_task(int cpu);
1136 extern void set_curr_task(int cpu, struct task_struct *p);
1137 
1138 void yield(void);
1139 
1140 /*
1141  * The default (Linux) execution domain.
1142  */
1143 extern struct exec_domain	default_exec_domain;
1144 
1145 union thread_union {
1146 	struct thread_info thread_info;
1147 	unsigned long stack[THREAD_SIZE/sizeof(long)];
1148 };
1149 
1150 #ifndef __HAVE_ARCH_KSTACK_END
kstack_end(void * addr)1151 static inline int kstack_end(void *addr)
1152 {
1153 	/* Reliable end of stack detection:
1154 	 * Some APM bios versions misalign the stack
1155 	 */
1156 	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1157 }
1158 #endif
1159 
1160 extern union thread_union init_thread_union;
1161 extern struct task_struct init_task;
1162 
1163 extern struct   mm_struct init_mm;
1164 
1165 #define find_task_by_pid(nr)	find_task_by_pid_type(PIDTYPE_PID, nr)
1166 extern struct task_struct *find_task_by_pid_type(int type, int pid);
1167 extern void set_special_pids(pid_t session, pid_t pgrp);
1168 extern void __set_special_pids(pid_t session, pid_t pgrp);
1169 
1170 /* per-UID process charging. */
1171 extern struct user_struct * alloc_uid(uid_t);
get_uid(struct user_struct * u)1172 static inline struct user_struct *get_uid(struct user_struct *u)
1173 {
1174 	atomic_inc(&u->__count);
1175 	return u;
1176 }
1177 extern void free_uid(struct user_struct *);
1178 extern void switch_uid(struct user_struct *);
1179 
1180 #include <asm/current.h>
1181 
1182 extern void do_timer(struct pt_regs *);
1183 
1184 extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state));
1185 extern int FASTCALL(wake_up_process(struct task_struct * tsk));
1186 extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
1187 						unsigned long clone_flags));
1188 #ifdef CONFIG_SMP
1189  extern void kick_process(struct task_struct *tsk);
1190 #else
kick_process(struct task_struct * tsk)1191  static inline void kick_process(struct task_struct *tsk) { }
1192 #endif
1193 extern void FASTCALL(sched_fork(struct task_struct * p, int clone_flags));
1194 extern void FASTCALL(sched_exit(struct task_struct * p));
1195 
1196 extern int in_group_p(gid_t);
1197 extern int in_egroup_p(gid_t);
1198 
1199 extern void proc_caches_init(void);
1200 extern void flush_signals(struct task_struct *);
1201 extern void flush_signal_handlers(struct task_struct *, int force_default);
1202 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1203 
dequeue_signal_lock(struct task_struct * tsk,sigset_t * mask,siginfo_t * info)1204 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1205 {
1206 	unsigned long flags;
1207 	int ret;
1208 
1209 	spin_lock_irqsave(&tsk->sighand->siglock, flags);
1210 	ret = dequeue_signal(tsk, mask, info);
1211 	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1212 
1213 	return ret;
1214 }
1215 
1216 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1217 			      sigset_t *mask);
1218 extern void unblock_all_signals(void);
1219 extern void release_task(struct task_struct * p);
1220 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1221 extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
1222 extern int force_sigsegv(int, struct task_struct *);
1223 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1224 extern int __kill_pg_info(int sig, struct siginfo *info, pid_t pgrp);
1225 extern int kill_pg_info(int, struct siginfo *, pid_t);
1226 extern int kill_proc_info(int, struct siginfo *, pid_t);
1227 extern int kill_proc_info_as_uid(int, struct siginfo *, pid_t, uid_t, uid_t, u32);
1228 extern void do_notify_parent(struct task_struct *, int);
1229 extern void force_sig(int, struct task_struct *);
1230 extern void force_sig_specific(int, struct task_struct *);
1231 extern int send_sig(int, struct task_struct *, int);
1232 extern void zap_other_threads(struct task_struct *p);
1233 extern int kill_pg(pid_t, int, int);
1234 extern int kill_proc(pid_t, int, int);
1235 extern struct sigqueue *sigqueue_alloc(void);
1236 extern void sigqueue_free(struct sigqueue *);
1237 extern int send_sigqueue(int, struct sigqueue *,  struct task_struct *);
1238 extern int send_group_sigqueue(int, struct sigqueue *,  struct task_struct *);
1239 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
1240 extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1241 
1242 /* These can be the second arg to send_sig_info/send_group_sig_info.  */
1243 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
1244 #define SEND_SIG_PRIV	((struct siginfo *) 1)
1245 #define SEND_SIG_FORCED	((struct siginfo *) 2)
1246 
is_si_special(const struct siginfo * info)1247 static inline int is_si_special(const struct siginfo *info)
1248 {
1249 	return info <= SEND_SIG_FORCED;
1250 }
1251 
1252 /* True if we are on the alternate signal stack.  */
1253 
on_sig_stack(unsigned long sp)1254 static inline int on_sig_stack(unsigned long sp)
1255 {
1256 	return (sp - current->sas_ss_sp < current->sas_ss_size);
1257 }
1258 
sas_ss_flags(unsigned long sp)1259 static inline int sas_ss_flags(unsigned long sp)
1260 {
1261 	return (current->sas_ss_size == 0 ? SS_DISABLE
1262 		: on_sig_stack(sp) ? SS_ONSTACK : 0);
1263 }
1264 
1265 /*
1266  * Routines for handling mm_structs
1267  */
1268 extern struct mm_struct * mm_alloc(void);
1269 
1270 /* mmdrop drops the mm and the page tables */
1271 extern void FASTCALL(__mmdrop(struct mm_struct *));
mmdrop(struct mm_struct * mm)1272 static inline void mmdrop(struct mm_struct * mm)
1273 {
1274 	if (atomic_dec_and_test(&mm->mm_count))
1275 		__mmdrop(mm);
1276 }
1277 
1278 /* mmput gets rid of the mappings and all user-space */
1279 extern void mmput(struct mm_struct *);
1280 /* Grab a reference to a task's mm, if it is not already going away */
1281 extern struct mm_struct *get_task_mm(struct task_struct *task);
1282 /* Remove the current tasks stale references to the old mm_struct */
1283 extern void mm_release(struct task_struct *, struct mm_struct *);
1284 
1285 extern int  copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1286 extern void flush_thread(void);
1287 extern void exit_thread(void);
1288 
1289 extern void exit_files(struct task_struct *);
1290 extern void __cleanup_signal(struct signal_struct *);
1291 extern void __cleanup_sighand(struct sighand_struct *);
1292 extern void exit_itimers(struct signal_struct *);
1293 
1294 extern NORET_TYPE void do_group_exit(int);
1295 
1296 extern void daemonize(const char *, ...);
1297 extern int allow_signal(int);
1298 extern int disallow_signal(int);
1299 extern struct task_struct *child_reaper;
1300 
1301 extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1302 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1303 struct task_struct *fork_idle(int);
1304 
1305 extern void set_task_comm(struct task_struct *tsk, char *from);
1306 extern void get_task_comm(char *to, struct task_struct *tsk);
1307 
1308 #ifdef CONFIG_SMP
1309 extern void wait_task_inactive(struct task_struct * p);
1310 #else
1311 #define wait_task_inactive(p)	do { } while (0)
1312 #endif
1313 
1314 #define remove_parent(p)	list_del_init(&(p)->sibling)
1315 #define add_parent(p)		list_add_tail(&(p)->sibling,&(p)->parent->children)
1316 
1317 #define next_task(p)	list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
1318 
1319 #define for_each_process(p) \
1320 	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1321 
1322 /*
1323  * Careful: do_each_thread/while_each_thread is a double loop so
1324  *          'break' will not work as expected - use goto instead.
1325  */
1326 #define do_each_thread(g, t) \
1327 	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1328 
1329 #define while_each_thread(g, t) \
1330 	while ((t = next_thread(t)) != g)
1331 
1332 /* de_thread depends on thread_group_leader not being a pid based check */
1333 #define thread_group_leader(p)	(p == p->group_leader)
1334 
next_thread(const struct task_struct * p)1335 static inline struct task_struct *next_thread(const struct task_struct *p)
1336 {
1337 	return list_entry(rcu_dereference(p->thread_group.next),
1338 			  struct task_struct, thread_group);
1339 }
1340 
thread_group_empty(struct task_struct * p)1341 static inline int thread_group_empty(struct task_struct *p)
1342 {
1343 	return list_empty(&p->thread_group);
1344 }
1345 
1346 #define delay_group_leader(p) \
1347 		(thread_group_leader(p) && !thread_group_empty(p))
1348 
1349 /*
1350  * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
1351  * subscriptions and synchronises with wait4().  Also used in procfs.  Also
1352  * pins the final release of task.io_context.  Also protects ->cpuset.
1353  *
1354  * Nests both inside and outside of read_lock(&tasklist_lock).
1355  * It must not be nested with write_lock_irq(&tasklist_lock),
1356  * neither inside nor outside.
1357  */
task_lock(struct task_struct * p)1358 static inline void task_lock(struct task_struct *p)
1359 {
1360 	spin_lock(&p->alloc_lock);
1361 }
1362 
task_unlock(struct task_struct * p)1363 static inline void task_unlock(struct task_struct *p)
1364 {
1365 	spin_unlock(&p->alloc_lock);
1366 }
1367 
1368 extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
1369 							unsigned long *flags);
1370 
unlock_task_sighand(struct task_struct * tsk,unsigned long * flags)1371 static inline void unlock_task_sighand(struct task_struct *tsk,
1372 						unsigned long *flags)
1373 {
1374 	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
1375 }
1376 
1377 #ifndef __HAVE_THREAD_FUNCTIONS
1378 
1379 #define task_thread_info(task) (task)->thread_info
1380 #define task_stack_page(task) ((void*)((task)->thread_info))
1381 
setup_thread_stack(struct task_struct * p,struct task_struct * org)1382 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
1383 {
1384 	*task_thread_info(p) = *task_thread_info(org);
1385 	task_thread_info(p)->task = p;
1386 }
1387 
end_of_stack(struct task_struct * p)1388 static inline unsigned long *end_of_stack(struct task_struct *p)
1389 {
1390 	return (unsigned long *)(p->thread_info + 1);
1391 }
1392 
1393 #endif
1394 
1395 /* set thread flags in other task's structures
1396  * - see asm/thread_info.h for TIF_xxxx flags available
1397  */
set_tsk_thread_flag(struct task_struct * tsk,int flag)1398 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1399 {
1400 	set_ti_thread_flag(task_thread_info(tsk), flag);
1401 }
1402 
clear_tsk_thread_flag(struct task_struct * tsk,int flag)1403 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1404 {
1405 	clear_ti_thread_flag(task_thread_info(tsk), flag);
1406 }
1407 
test_and_set_tsk_thread_flag(struct task_struct * tsk,int flag)1408 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1409 {
1410 	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1411 }
1412 
test_and_clear_tsk_thread_flag(struct task_struct * tsk,int flag)1413 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1414 {
1415 	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1416 }
1417 
test_tsk_thread_flag(struct task_struct * tsk,int flag)1418 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1419 {
1420 	return test_ti_thread_flag(task_thread_info(tsk), flag);
1421 }
1422 
set_tsk_need_resched(struct task_struct * tsk)1423 static inline void set_tsk_need_resched(struct task_struct *tsk)
1424 {
1425 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1426 }
1427 
clear_tsk_need_resched(struct task_struct * tsk)1428 static inline void clear_tsk_need_resched(struct task_struct *tsk)
1429 {
1430 	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1431 }
1432 
signal_pending(struct task_struct * p)1433 static inline int signal_pending(struct task_struct *p)
1434 {
1435 	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1436 }
1437 
need_resched(void)1438 static inline int need_resched(void)
1439 {
1440 	return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1441 }
1442 
1443 /*
1444  * cond_resched() and cond_resched_lock(): latency reduction via
1445  * explicit rescheduling in places that are safe. The return
1446  * value indicates whether a reschedule was done in fact.
1447  * cond_resched_lock() will drop the spinlock before scheduling,
1448  * cond_resched_softirq() will enable bhs before scheduling.
1449  */
1450 extern int cond_resched(void);
1451 extern int cond_resched_lock(spinlock_t * lock);
1452 extern int cond_resched_softirq(void);
1453 
1454 /*
1455  * Does a critical section need to be broken due to another
1456  * task waiting?:
1457  */
1458 #if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
1459 # define need_lockbreak(lock) ((lock)->break_lock)
1460 #else
1461 # define need_lockbreak(lock) 0
1462 #endif
1463 
1464 /*
1465  * Does a critical section need to be broken due to another
1466  * task waiting or preemption being signalled:
1467  */
lock_need_resched(spinlock_t * lock)1468 static inline int lock_need_resched(spinlock_t *lock)
1469 {
1470 	if (need_lockbreak(lock) || need_resched())
1471 		return 1;
1472 	return 0;
1473 }
1474 
1475 /* Reevaluate whether the task has signals pending delivery.
1476    This is required every time the blocked sigset_t changes.
1477    callers must hold sighand->siglock.  */
1478 
1479 extern FASTCALL(void recalc_sigpending_tsk(struct task_struct *t));
1480 extern void recalc_sigpending(void);
1481 
1482 extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1483 
1484 /*
1485  * Wrappers for p->thread_info->cpu access. No-op on UP.
1486  */
1487 #ifdef CONFIG_SMP
1488 
task_cpu(const struct task_struct * p)1489 static inline unsigned int task_cpu(const struct task_struct *p)
1490 {
1491 	return task_thread_info(p)->cpu;
1492 }
1493 
set_task_cpu(struct task_struct * p,unsigned int cpu)1494 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1495 {
1496 	task_thread_info(p)->cpu = cpu;
1497 }
1498 
1499 #else
1500 
task_cpu(const struct task_struct * p)1501 static inline unsigned int task_cpu(const struct task_struct *p)
1502 {
1503 	return 0;
1504 }
1505 
set_task_cpu(struct task_struct * p,unsigned int cpu)1506 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1507 {
1508 }
1509 
1510 #endif /* CONFIG_SMP */
1511 
1512 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1513 extern void arch_pick_mmap_layout(struct mm_struct *mm);
1514 #else
arch_pick_mmap_layout(struct mm_struct * mm)1515 static inline void arch_pick_mmap_layout(struct mm_struct *mm)
1516 {
1517 	mm->mmap_base = TASK_UNMAPPED_BASE;
1518 	mm->get_unmapped_area = arch_get_unmapped_area;
1519 	mm->unmap_area = arch_unmap_area;
1520 }
1521 #endif
1522 
1523 extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
1524 extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
1525 
1526 #include <linux/sysdev.h>
1527 extern int sched_mc_power_savings, sched_smt_power_savings;
1528 extern struct sysdev_attribute attr_sched_mc_power_savings, attr_sched_smt_power_savings;
1529 extern int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls);
1530 
1531 extern void normalize_rt_tasks(void);
1532 
1533 #ifdef CONFIG_PM
1534 /*
1535  * Check if a process has been frozen
1536  */
frozen(struct task_struct * p)1537 static inline int frozen(struct task_struct *p)
1538 {
1539 	return p->flags & PF_FROZEN;
1540 }
1541 
1542 /*
1543  * Check if there is a request to freeze a process
1544  */
freezing(struct task_struct * p)1545 static inline int freezing(struct task_struct *p)
1546 {
1547 	return p->flags & PF_FREEZE;
1548 }
1549 
1550 /*
1551  * Request that a process be frozen
1552  * FIXME: SMP problem. We may not modify other process' flags!
1553  */
freeze(struct task_struct * p)1554 static inline void freeze(struct task_struct *p)
1555 {
1556 	p->flags |= PF_FREEZE;
1557 }
1558 
1559 /*
1560  * Sometimes we may need to cancel the previous 'freeze' request
1561  */
do_not_freeze(struct task_struct * p)1562 static inline void do_not_freeze(struct task_struct *p)
1563 {
1564 	p->flags &= ~PF_FREEZE;
1565 }
1566 
1567 /*
1568  * Wake up a frozen process
1569  */
thaw_process(struct task_struct * p)1570 static inline int thaw_process(struct task_struct *p)
1571 {
1572 	if (frozen(p)) {
1573 		p->flags &= ~PF_FROZEN;
1574 		wake_up_process(p);
1575 		return 1;
1576 	}
1577 	return 0;
1578 }
1579 
1580 /*
1581  * freezing is complete, mark process as frozen
1582  */
frozen_process(struct task_struct * p)1583 static inline void frozen_process(struct task_struct *p)
1584 {
1585 	p->flags = (p->flags & ~PF_FREEZE) | PF_FROZEN;
1586 }
1587 
1588 extern void refrigerator(void);
1589 extern int freeze_processes(void);
1590 extern void thaw_processes(void);
1591 
try_to_freeze(void)1592 static inline int try_to_freeze(void)
1593 {
1594 	if (freezing(current)) {
1595 		refrigerator();
1596 		return 1;
1597 	} else
1598 		return 0;
1599 }
1600 #else
frozen(struct task_struct * p)1601 static inline int frozen(struct task_struct *p) { return 0; }
freezing(struct task_struct * p)1602 static inline int freezing(struct task_struct *p) { return 0; }
freeze(struct task_struct * p)1603 static inline void freeze(struct task_struct *p) { BUG(); }
thaw_process(struct task_struct * p)1604 static inline int thaw_process(struct task_struct *p) { return 1; }
frozen_process(struct task_struct * p)1605 static inline void frozen_process(struct task_struct *p) { BUG(); }
1606 
refrigerator(void)1607 static inline void refrigerator(void) {}
freeze_processes(void)1608 static inline int freeze_processes(void) { BUG(); return 0; }
thaw_processes(void)1609 static inline void thaw_processes(void) {}
1610 
try_to_freeze(void)1611 static inline int try_to_freeze(void) { return 0; }
1612 
1613 #endif /* CONFIG_PM */
1614 #endif /* __KERNEL__ */
1615 
1616 #endif
1617