xref: /linux-6.15/include/linux/sched.h (revision b9482378)
1 #ifndef _LINUX_SCHED_H
2 #define _LINUX_SCHED_H
3 
4 /*
5  * cloning flags:
6  */
7 #define CSIGNAL		0x000000ff	/* signal mask to be sent at exit */
8 #define CLONE_VM	0x00000100	/* set if VM shared between processes */
9 #define CLONE_FS	0x00000200	/* set if fs info shared between processes */
10 #define CLONE_FILES	0x00000400	/* set if open files shared between processes */
11 #define CLONE_SIGHAND	0x00000800	/* set if signal handlers and blocked signals shared */
12 #define CLONE_PTRACE	0x00002000	/* set if we want to let tracing continue on the child too */
13 #define CLONE_VFORK	0x00004000	/* set if the parent wants the child to wake it up on mm_release */
14 #define CLONE_PARENT	0x00008000	/* set if we want to have the same parent as the cloner */
15 #define CLONE_THREAD	0x00010000	/* Same thread group? */
16 #define CLONE_NEWNS	0x00020000	/* New namespace group? */
17 #define CLONE_SYSVSEM	0x00040000	/* share system V SEM_UNDO semantics */
18 #define CLONE_SETTLS	0x00080000	/* create a new TLS for the child */
19 #define CLONE_PARENT_SETTID	0x00100000	/* set the TID in the parent */
20 #define CLONE_CHILD_CLEARTID	0x00200000	/* clear the TID in the child */
21 #define CLONE_DETACHED		0x00400000	/* Unused, ignored */
22 #define CLONE_UNTRACED		0x00800000	/* set if the tracing process can't force CLONE_PTRACE on this clone */
23 #define CLONE_CHILD_SETTID	0x01000000	/* set the TID in the child */
24 #define CLONE_STOPPED		0x02000000	/* Start in stopped state */
25 #define CLONE_NEWUTS		0x04000000	/* New utsname group? */
26 #define CLONE_NEWIPC		0x08000000	/* New ipcs */
27 #define CLONE_NEWUSER		0x10000000	/* New user namespace */
28 #define CLONE_NEWPID		0x20000000	/* New pid namespace */
29 #define CLONE_NEWNET		0x40000000	/* New network namespace */
30 #define CLONE_IO		0x80000000	/* Clone io context */
31 
32 /*
33  * Scheduling policies
34  */
35 #define SCHED_NORMAL		0
36 #define SCHED_FIFO		1
37 #define SCHED_RR		2
38 #define SCHED_BATCH		3
39 /* SCHED_ISO: reserved but not implemented yet */
40 #define SCHED_IDLE		5
41 
42 #ifdef __KERNEL__
43 
44 struct sched_param {
45 	int sched_priority;
46 };
47 
48 #include <asm/param.h>	/* for HZ */
49 
50 #include <linux/capability.h>
51 #include <linux/threads.h>
52 #include <linux/kernel.h>
53 #include <linux/types.h>
54 #include <linux/timex.h>
55 #include <linux/jiffies.h>
56 #include <linux/rbtree.h>
57 #include <linux/thread_info.h>
58 #include <linux/cpumask.h>
59 #include <linux/errno.h>
60 #include <linux/nodemask.h>
61 #include <linux/mm_types.h>
62 
63 #include <asm/system.h>
64 #include <asm/semaphore.h>
65 #include <asm/page.h>
66 #include <asm/ptrace.h>
67 #include <asm/cputime.h>
68 
69 #include <linux/smp.h>
70 #include <linux/sem.h>
71 #include <linux/signal.h>
72 #include <linux/securebits.h>
73 #include <linux/fs_struct.h>
74 #include <linux/compiler.h>
75 #include <linux/completion.h>
76 #include <linux/pid.h>
77 #include <linux/percpu.h>
78 #include <linux/topology.h>
79 #include <linux/proportions.h>
80 #include <linux/seccomp.h>
81 #include <linux/rcupdate.h>
82 #include <linux/rtmutex.h>
83 
84 #include <linux/time.h>
85 #include <linux/param.h>
86 #include <linux/resource.h>
87 #include <linux/timer.h>
88 #include <linux/hrtimer.h>
89 #include <linux/task_io_accounting.h>
90 #include <linux/kobject.h>
91 #include <linux/latencytop.h>
92 
93 #include <asm/processor.h>
94 
95 struct mem_cgroup;
96 struct exec_domain;
97 struct futex_pi_state;
98 struct robust_list_head;
99 struct bio;
100 
101 /*
102  * List of flags we want to share for kernel threads,
103  * if only because they are not used by them anyway.
104  */
105 #define CLONE_KERNEL	(CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
106 
107 /*
108  * These are the constant used to fake the fixed-point load-average
109  * counting. Some notes:
110  *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
111  *    a load-average precision of 10 bits integer + 11 bits fractional
112  *  - if you want to count load-averages more often, you need more
113  *    precision, or rounding will get you. With 2-second counting freq,
114  *    the EXP_n values would be 1981, 2034 and 2043 if still using only
115  *    11 bit fractions.
116  */
117 extern unsigned long avenrun[];		/* Load averages */
118 
119 #define FSHIFT		11		/* nr of bits of precision */
120 #define FIXED_1		(1<<FSHIFT)	/* 1.0 as fixed-point */
121 #define LOAD_FREQ	(5*HZ+1)	/* 5 sec intervals */
122 #define EXP_1		1884		/* 1/exp(5sec/1min) as fixed-point */
123 #define EXP_5		2014		/* 1/exp(5sec/5min) */
124 #define EXP_15		2037		/* 1/exp(5sec/15min) */
125 
126 #define CALC_LOAD(load,exp,n) \
127 	load *= exp; \
128 	load += n*(FIXED_1-exp); \
129 	load >>= FSHIFT;
130 
131 extern unsigned long total_forks;
132 extern int nr_threads;
133 DECLARE_PER_CPU(unsigned long, process_counts);
134 extern int nr_processes(void);
135 extern unsigned long nr_running(void);
136 extern unsigned long nr_uninterruptible(void);
137 extern unsigned long nr_active(void);
138 extern unsigned long nr_iowait(void);
139 extern unsigned long weighted_cpuload(const int cpu);
140 
141 struct seq_file;
142 struct cfs_rq;
143 struct task_group;
144 #ifdef CONFIG_SCHED_DEBUG
145 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
146 extern void proc_sched_set_task(struct task_struct *p);
147 extern void
148 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
149 #else
150 static inline void
151 proc_sched_show_task(struct task_struct *p, struct seq_file *m)
152 {
153 }
154 static inline void proc_sched_set_task(struct task_struct *p)
155 {
156 }
157 static inline void
158 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
159 {
160 }
161 #endif
162 
163 /*
164  * Task state bitmask. NOTE! These bits are also
165  * encoded in fs/proc/array.c: get_task_state().
166  *
167  * We have two separate sets of flags: task->state
168  * is about runnability, while task->exit_state are
169  * about the task exiting. Confusing, but this way
170  * modifying one set can't modify the other one by
171  * mistake.
172  */
173 #define TASK_RUNNING		0
174 #define TASK_INTERRUPTIBLE	1
175 #define TASK_UNINTERRUPTIBLE	2
176 #define __TASK_STOPPED		4
177 #define __TASK_TRACED		8
178 /* in tsk->exit_state */
179 #define EXIT_ZOMBIE		16
180 #define EXIT_DEAD		32
181 /* in tsk->state again */
182 #define TASK_DEAD		64
183 #define TASK_WAKEKILL		128
184 
185 /* Convenience macros for the sake of set_task_state */
186 #define TASK_KILLABLE		(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
187 #define TASK_STOPPED		(TASK_WAKEKILL | __TASK_STOPPED)
188 #define TASK_TRACED		(TASK_WAKEKILL | __TASK_TRACED)
189 
190 /* Convenience macros for the sake of wake_up */
191 #define TASK_NORMAL		(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
192 #define TASK_ALL		(TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
193 
194 /* get_task_state() */
195 #define TASK_REPORT		(TASK_RUNNING | TASK_INTERRUPTIBLE | \
196 				 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
197 				 __TASK_TRACED)
198 
199 #define task_is_traced(task)	((task->state & __TASK_TRACED) != 0)
200 #define task_is_stopped(task)	((task->state & __TASK_STOPPED) != 0)
201 #define task_is_stopped_or_traced(task)	\
202 			((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
203 #define task_contributes_to_load(task)	\
204 				((task->state & TASK_UNINTERRUPTIBLE) != 0)
205 
206 #define __set_task_state(tsk, state_value)		\
207 	do { (tsk)->state = (state_value); } while (0)
208 #define set_task_state(tsk, state_value)		\
209 	set_mb((tsk)->state, (state_value))
210 
211 /*
212  * set_current_state() includes a barrier so that the write of current->state
213  * is correctly serialised wrt the caller's subsequent test of whether to
214  * actually sleep:
215  *
216  *	set_current_state(TASK_UNINTERRUPTIBLE);
217  *	if (do_i_need_to_sleep())
218  *		schedule();
219  *
220  * If the caller does not need such serialisation then use __set_current_state()
221  */
222 #define __set_current_state(state_value)			\
223 	do { current->state = (state_value); } while (0)
224 #define set_current_state(state_value)		\
225 	set_mb(current->state, (state_value))
226 
227 /* Task command name length */
228 #define TASK_COMM_LEN 16
229 
230 #include <linux/spinlock.h>
231 
232 /*
233  * This serializes "schedule()" and also protects
234  * the run-queue from deletions/modifications (but
235  * _adding_ to the beginning of the run-queue has
236  * a separate lock).
237  */
238 extern rwlock_t tasklist_lock;
239 extern spinlock_t mmlist_lock;
240 
241 struct task_struct;
242 
243 extern void sched_init(void);
244 extern void sched_init_smp(void);
245 extern void init_idle(struct task_struct *idle, int cpu);
246 extern void init_idle_bootup_task(struct task_struct *idle);
247 
248 extern cpumask_t nohz_cpu_mask;
249 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
250 extern int select_nohz_load_balancer(int cpu);
251 #else
252 static inline int select_nohz_load_balancer(int cpu)
253 {
254 	return 0;
255 }
256 #endif
257 
258 extern unsigned long rt_needs_cpu(int cpu);
259 
260 /*
261  * Only dump TASK_* tasks. (0 for all tasks)
262  */
263 extern void show_state_filter(unsigned long state_filter);
264 
265 static inline void show_state(void)
266 {
267 	show_state_filter(0);
268 }
269 
270 extern void show_regs(struct pt_regs *);
271 
272 /*
273  * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
274  * task), SP is the stack pointer of the first frame that should be shown in the back
275  * trace (or NULL if the entire call-chain of the task should be shown).
276  */
277 extern void show_stack(struct task_struct *task, unsigned long *sp);
278 
279 void io_schedule(void);
280 long io_schedule_timeout(long timeout);
281 
282 extern void cpu_init (void);
283 extern void trap_init(void);
284 extern void account_process_tick(struct task_struct *task, int user);
285 extern void update_process_times(int user);
286 extern void scheduler_tick(void);
287 extern void hrtick_resched(void);
288 
289 extern void sched_show_task(struct task_struct *p);
290 
291 #ifdef CONFIG_DETECT_SOFTLOCKUP
292 extern void softlockup_tick(void);
293 extern void spawn_softlockup_task(void);
294 extern void touch_softlockup_watchdog(void);
295 extern void touch_all_softlockup_watchdogs(void);
296 extern unsigned long  softlockup_thresh;
297 extern unsigned long sysctl_hung_task_check_count;
298 extern unsigned long sysctl_hung_task_timeout_secs;
299 extern unsigned long sysctl_hung_task_warnings;
300 #else
301 static inline void softlockup_tick(void)
302 {
303 }
304 static inline void spawn_softlockup_task(void)
305 {
306 }
307 static inline void touch_softlockup_watchdog(void)
308 {
309 }
310 static inline void touch_all_softlockup_watchdogs(void)
311 {
312 }
313 #endif
314 
315 
316 /* Attach to any functions which should be ignored in wchan output. */
317 #define __sched		__attribute__((__section__(".sched.text")))
318 
319 /* Linker adds these: start and end of __sched functions */
320 extern char __sched_text_start[], __sched_text_end[];
321 
322 /* Is this address in the __sched functions? */
323 extern int in_sched_functions(unsigned long addr);
324 
325 #define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
326 extern signed long schedule_timeout(signed long timeout);
327 extern signed long schedule_timeout_interruptible(signed long timeout);
328 extern signed long schedule_timeout_killable(signed long timeout);
329 extern signed long schedule_timeout_uninterruptible(signed long timeout);
330 asmlinkage void schedule(void);
331 
332 struct nsproxy;
333 struct user_namespace;
334 
335 /* Maximum number of active map areas.. This is a random (large) number */
336 #define DEFAULT_MAX_MAP_COUNT	65536
337 
338 extern int sysctl_max_map_count;
339 
340 #include <linux/aio.h>
341 
342 extern unsigned long
343 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
344 		       unsigned long, unsigned long);
345 extern unsigned long
346 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
347 			  unsigned long len, unsigned long pgoff,
348 			  unsigned long flags);
349 extern void arch_unmap_area(struct mm_struct *, unsigned long);
350 extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
351 
352 #if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
353 /*
354  * The mm counters are not protected by its page_table_lock,
355  * so must be incremented atomically.
356  */
357 #define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
358 #define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
359 #define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
360 #define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
361 #define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
362 
363 #else  /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
364 /*
365  * The mm counters are protected by its page_table_lock,
366  * so can be incremented directly.
367  */
368 #define set_mm_counter(mm, member, value) (mm)->_##member = (value)
369 #define get_mm_counter(mm, member) ((mm)->_##member)
370 #define add_mm_counter(mm, member, value) (mm)->_##member += (value)
371 #define inc_mm_counter(mm, member) (mm)->_##member++
372 #define dec_mm_counter(mm, member) (mm)->_##member--
373 
374 #endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
375 
376 #define get_mm_rss(mm)					\
377 	(get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
378 #define update_hiwater_rss(mm)	do {			\
379 	unsigned long _rss = get_mm_rss(mm);		\
380 	if ((mm)->hiwater_rss < _rss)			\
381 		(mm)->hiwater_rss = _rss;		\
382 } while (0)
383 #define update_hiwater_vm(mm)	do {			\
384 	if ((mm)->hiwater_vm < (mm)->total_vm)		\
385 		(mm)->hiwater_vm = (mm)->total_vm;	\
386 } while (0)
387 
388 extern void set_dumpable(struct mm_struct *mm, int value);
389 extern int get_dumpable(struct mm_struct *mm);
390 
391 /* mm flags */
392 /* dumpable bits */
393 #define MMF_DUMPABLE      0  /* core dump is permitted */
394 #define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
395 #define MMF_DUMPABLE_BITS 2
396 
397 /* coredump filter bits */
398 #define MMF_DUMP_ANON_PRIVATE	2
399 #define MMF_DUMP_ANON_SHARED	3
400 #define MMF_DUMP_MAPPED_PRIVATE	4
401 #define MMF_DUMP_MAPPED_SHARED	5
402 #define MMF_DUMP_ELF_HEADERS	6
403 #define MMF_DUMP_FILTER_SHIFT	MMF_DUMPABLE_BITS
404 #define MMF_DUMP_FILTER_BITS	5
405 #define MMF_DUMP_FILTER_MASK \
406 	(((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
407 #define MMF_DUMP_FILTER_DEFAULT \
408 	((1 << MMF_DUMP_ANON_PRIVATE) |	(1 << MMF_DUMP_ANON_SHARED))
409 
410 struct sighand_struct {
411 	atomic_t		count;
412 	struct k_sigaction	action[_NSIG];
413 	spinlock_t		siglock;
414 	wait_queue_head_t	signalfd_wqh;
415 };
416 
417 struct pacct_struct {
418 	int			ac_flag;
419 	long			ac_exitcode;
420 	unsigned long		ac_mem;
421 	cputime_t		ac_utime, ac_stime;
422 	unsigned long		ac_minflt, ac_majflt;
423 };
424 
425 /*
426  * NOTE! "signal_struct" does not have it's own
427  * locking, because a shared signal_struct always
428  * implies a shared sighand_struct, so locking
429  * sighand_struct is always a proper superset of
430  * the locking of signal_struct.
431  */
432 struct signal_struct {
433 	atomic_t		count;
434 	atomic_t		live;
435 
436 	wait_queue_head_t	wait_chldexit;	/* for wait4() */
437 
438 	/* current thread group signal load-balancing target: */
439 	struct task_struct	*curr_target;
440 
441 	/* shared signal handling: */
442 	struct sigpending	shared_pending;
443 
444 	/* thread group exit support */
445 	int			group_exit_code;
446 	/* overloaded:
447 	 * - notify group_exit_task when ->count is equal to notify_count
448 	 * - everyone except group_exit_task is stopped during signal delivery
449 	 *   of fatal signals, group_exit_task processes the signal.
450 	 */
451 	struct task_struct	*group_exit_task;
452 	int			notify_count;
453 
454 	/* thread group stop support, overloads group_exit_code too */
455 	int			group_stop_count;
456 	unsigned int		flags; /* see SIGNAL_* flags below */
457 
458 	/* POSIX.1b Interval Timers */
459 	struct list_head posix_timers;
460 
461 	/* ITIMER_REAL timer for the process */
462 	struct hrtimer real_timer;
463 	struct pid *leader_pid;
464 	ktime_t it_real_incr;
465 
466 	/* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
467 	cputime_t it_prof_expires, it_virt_expires;
468 	cputime_t it_prof_incr, it_virt_incr;
469 
470 	/* job control IDs */
471 
472 	/*
473 	 * pgrp and session fields are deprecated.
474 	 * use the task_session_Xnr and task_pgrp_Xnr routines below
475 	 */
476 
477 	union {
478 		pid_t pgrp __deprecated;
479 		pid_t __pgrp;
480 	};
481 
482 	struct pid *tty_old_pgrp;
483 
484 	union {
485 		pid_t session __deprecated;
486 		pid_t __session;
487 	};
488 
489 	/* boolean value for session group leader */
490 	int leader;
491 
492 	struct tty_struct *tty; /* NULL if no tty */
493 
494 	/*
495 	 * Cumulative resource counters for dead threads in the group,
496 	 * and for reaped dead child processes forked by this group.
497 	 * Live threads maintain their own counters and add to these
498 	 * in __exit_signal, except for the group leader.
499 	 */
500 	cputime_t utime, stime, cutime, cstime;
501 	cputime_t gtime;
502 	cputime_t cgtime;
503 	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
504 	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
505 	unsigned long inblock, oublock, cinblock, coublock;
506 
507 	/*
508 	 * Cumulative ns of scheduled CPU time for dead threads in the
509 	 * group, not including a zombie group leader.  (This only differs
510 	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
511 	 * other than jiffies.)
512 	 */
513 	unsigned long long sum_sched_runtime;
514 
515 	/*
516 	 * We don't bother to synchronize most readers of this at all,
517 	 * because there is no reader checking a limit that actually needs
518 	 * to get both rlim_cur and rlim_max atomically, and either one
519 	 * alone is a single word that can safely be read normally.
520 	 * getrlimit/setrlimit use task_lock(current->group_leader) to
521 	 * protect this instead of the siglock, because they really
522 	 * have no need to disable irqs.
523 	 */
524 	struct rlimit rlim[RLIM_NLIMITS];
525 
526 	struct list_head cpu_timers[3];
527 
528 	/* keep the process-shared keyrings here so that they do the right
529 	 * thing in threads created with CLONE_THREAD */
530 #ifdef CONFIG_KEYS
531 	struct key *session_keyring;	/* keyring inherited over fork */
532 	struct key *process_keyring;	/* keyring private to this process */
533 #endif
534 #ifdef CONFIG_BSD_PROCESS_ACCT
535 	struct pacct_struct pacct;	/* per-process accounting information */
536 #endif
537 #ifdef CONFIG_TASKSTATS
538 	struct taskstats *stats;
539 #endif
540 #ifdef CONFIG_AUDIT
541 	unsigned audit_tty;
542 	struct tty_audit_buf *tty_audit_buf;
543 #endif
544 };
545 
546 /* Context switch must be unlocked if interrupts are to be enabled */
547 #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
548 # define __ARCH_WANT_UNLOCKED_CTXSW
549 #endif
550 
551 /*
552  * Bits in flags field of signal_struct.
553  */
554 #define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
555 #define SIGNAL_STOP_DEQUEUED	0x00000002 /* stop signal dequeued */
556 #define SIGNAL_STOP_CONTINUED	0x00000004 /* SIGCONT since WCONTINUED reap */
557 #define SIGNAL_GROUP_EXIT	0x00000008 /* group exit in progress */
558 
559 /* If true, all threads except ->group_exit_task have pending SIGKILL */
560 static inline int signal_group_exit(const struct signal_struct *sig)
561 {
562 	return	(sig->flags & SIGNAL_GROUP_EXIT) ||
563 		(sig->group_exit_task != NULL);
564 }
565 
566 /*
567  * Some day this will be a full-fledged user tracking system..
568  */
569 struct user_struct {
570 	atomic_t __count;	/* reference count */
571 	atomic_t processes;	/* How many processes does this user have? */
572 	atomic_t files;		/* How many open files does this user have? */
573 	atomic_t sigpending;	/* How many pending signals does this user have? */
574 #ifdef CONFIG_INOTIFY_USER
575 	atomic_t inotify_watches; /* How many inotify watches does this user have? */
576 	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
577 #endif
578 #ifdef CONFIG_POSIX_MQUEUE
579 	/* protected by mq_lock	*/
580 	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
581 #endif
582 	unsigned long locked_shm; /* How many pages of mlocked shm ? */
583 
584 #ifdef CONFIG_KEYS
585 	struct key *uid_keyring;	/* UID specific keyring */
586 	struct key *session_keyring;	/* UID's default session keyring */
587 #endif
588 
589 	/* Hash table maintenance information */
590 	struct hlist_node uidhash_node;
591 	uid_t uid;
592 
593 #ifdef CONFIG_USER_SCHED
594 	struct task_group *tg;
595 #ifdef CONFIG_SYSFS
596 	struct kobject kobj;
597 	struct work_struct work;
598 #endif
599 #endif
600 };
601 
602 extern int uids_sysfs_init(void);
603 
604 extern struct user_struct *find_user(uid_t);
605 
606 extern struct user_struct root_user;
607 #define INIT_USER (&root_user)
608 
609 struct backing_dev_info;
610 struct reclaim_state;
611 
612 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
613 struct sched_info {
614 	/* cumulative counters */
615 	unsigned long pcount;	      /* # of times run on this cpu */
616 	unsigned long long cpu_time,  /* time spent on the cpu */
617 			   run_delay; /* time spent waiting on a runqueue */
618 
619 	/* timestamps */
620 	unsigned long long last_arrival,/* when we last ran on a cpu */
621 			   last_queued;	/* when we were last queued to run */
622 #ifdef CONFIG_SCHEDSTATS
623 	/* BKL stats */
624 	unsigned int bkl_count;
625 #endif
626 };
627 #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
628 
629 #ifdef CONFIG_SCHEDSTATS
630 extern const struct file_operations proc_schedstat_operations;
631 #endif /* CONFIG_SCHEDSTATS */
632 
633 #ifdef CONFIG_TASK_DELAY_ACCT
634 struct task_delay_info {
635 	spinlock_t	lock;
636 	unsigned int	flags;	/* Private per-task flags */
637 
638 	/* For each stat XXX, add following, aligned appropriately
639 	 *
640 	 * struct timespec XXX_start, XXX_end;
641 	 * u64 XXX_delay;
642 	 * u32 XXX_count;
643 	 *
644 	 * Atomicity of updates to XXX_delay, XXX_count protected by
645 	 * single lock above (split into XXX_lock if contention is an issue).
646 	 */
647 
648 	/*
649 	 * XXX_count is incremented on every XXX operation, the delay
650 	 * associated with the operation is added to XXX_delay.
651 	 * XXX_delay contains the accumulated delay time in nanoseconds.
652 	 */
653 	struct timespec blkio_start, blkio_end;	/* Shared by blkio, swapin */
654 	u64 blkio_delay;	/* wait for sync block io completion */
655 	u64 swapin_delay;	/* wait for swapin block io completion */
656 	u32 blkio_count;	/* total count of the number of sync block */
657 				/* io operations performed */
658 	u32 swapin_count;	/* total count of the number of swapin block */
659 				/* io operations performed */
660 };
661 #endif	/* CONFIG_TASK_DELAY_ACCT */
662 
663 static inline int sched_info_on(void)
664 {
665 #ifdef CONFIG_SCHEDSTATS
666 	return 1;
667 #elif defined(CONFIG_TASK_DELAY_ACCT)
668 	extern int delayacct_on;
669 	return delayacct_on;
670 #else
671 	return 0;
672 #endif
673 }
674 
675 enum cpu_idle_type {
676 	CPU_IDLE,
677 	CPU_NOT_IDLE,
678 	CPU_NEWLY_IDLE,
679 	CPU_MAX_IDLE_TYPES
680 };
681 
682 /*
683  * sched-domains (multiprocessor balancing) declarations:
684  */
685 
686 /*
687  * Increase resolution of nice-level calculations:
688  */
689 #define SCHED_LOAD_SHIFT	10
690 #define SCHED_LOAD_SCALE	(1L << SCHED_LOAD_SHIFT)
691 
692 #define SCHED_LOAD_SCALE_FUZZ	SCHED_LOAD_SCALE
693 
694 #ifdef CONFIG_SMP
695 #define SD_LOAD_BALANCE		1	/* Do load balancing on this domain. */
696 #define SD_BALANCE_NEWIDLE	2	/* Balance when about to become idle */
697 #define SD_BALANCE_EXEC		4	/* Balance on exec */
698 #define SD_BALANCE_FORK		8	/* Balance on fork, clone */
699 #define SD_WAKE_IDLE		16	/* Wake to idle CPU on task wakeup */
700 #define SD_WAKE_AFFINE		32	/* Wake task to waking CPU */
701 #define SD_WAKE_BALANCE		64	/* Perform balancing at task wakeup */
702 #define SD_SHARE_CPUPOWER	128	/* Domain members share cpu power */
703 #define SD_POWERSAVINGS_BALANCE	256	/* Balance for power savings */
704 #define SD_SHARE_PKG_RESOURCES	512	/* Domain members share cpu pkg resources */
705 #define SD_SERIALIZE		1024	/* Only a single load balancing instance */
706 
707 #define BALANCE_FOR_MC_POWER	\
708 	(sched_smt_power_savings ? SD_POWERSAVINGS_BALANCE : 0)
709 
710 #define BALANCE_FOR_PKG_POWER	\
711 	((sched_mc_power_savings || sched_smt_power_savings) ?	\
712 	 SD_POWERSAVINGS_BALANCE : 0)
713 
714 #define test_sd_parent(sd, flag)	((sd->parent &&		\
715 					 (sd->parent->flags & flag)) ? 1 : 0)
716 
717 
718 struct sched_group {
719 	struct sched_group *next;	/* Must be a circular list */
720 	cpumask_t cpumask;
721 
722 	/*
723 	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
724 	 * single CPU. This is read only (except for setup, hotplug CPU).
725 	 * Note : Never change cpu_power without recompute its reciprocal
726 	 */
727 	unsigned int __cpu_power;
728 	/*
729 	 * reciprocal value of cpu_power to avoid expensive divides
730 	 * (see include/linux/reciprocal_div.h)
731 	 */
732 	u32 reciprocal_cpu_power;
733 };
734 
735 struct sched_domain {
736 	/* These fields must be setup */
737 	struct sched_domain *parent;	/* top domain must be null terminated */
738 	struct sched_domain *child;	/* bottom domain must be null terminated */
739 	struct sched_group *groups;	/* the balancing groups of the domain */
740 	cpumask_t span;			/* span of all CPUs in this domain */
741 	unsigned long min_interval;	/* Minimum balance interval ms */
742 	unsigned long max_interval;	/* Maximum balance interval ms */
743 	unsigned int busy_factor;	/* less balancing by factor if busy */
744 	unsigned int imbalance_pct;	/* No balance until over watermark */
745 	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
746 	unsigned int busy_idx;
747 	unsigned int idle_idx;
748 	unsigned int newidle_idx;
749 	unsigned int wake_idx;
750 	unsigned int forkexec_idx;
751 	int flags;			/* See SD_* */
752 
753 	/* Runtime fields. */
754 	unsigned long last_balance;	/* init to jiffies. units in jiffies */
755 	unsigned int balance_interval;	/* initialise to 1. units in ms. */
756 	unsigned int nr_balance_failed; /* initialise to 0 */
757 
758 #ifdef CONFIG_SCHEDSTATS
759 	/* load_balance() stats */
760 	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
761 	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
762 	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
763 	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
764 	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
765 	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
766 	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
767 	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
768 
769 	/* Active load balancing */
770 	unsigned int alb_count;
771 	unsigned int alb_failed;
772 	unsigned int alb_pushed;
773 
774 	/* SD_BALANCE_EXEC stats */
775 	unsigned int sbe_count;
776 	unsigned int sbe_balanced;
777 	unsigned int sbe_pushed;
778 
779 	/* SD_BALANCE_FORK stats */
780 	unsigned int sbf_count;
781 	unsigned int sbf_balanced;
782 	unsigned int sbf_pushed;
783 
784 	/* try_to_wake_up() stats */
785 	unsigned int ttwu_wake_remote;
786 	unsigned int ttwu_move_affine;
787 	unsigned int ttwu_move_balance;
788 #endif
789 };
790 
791 extern void partition_sched_domains(int ndoms_new, cpumask_t *doms_new);
792 
793 #endif	/* CONFIG_SMP */
794 
795 /*
796  * A runqueue laden with a single nice 0 task scores a weighted_cpuload of
797  * SCHED_LOAD_SCALE. This function returns 1 if any cpu is laden with a
798  * task of nice 0 or enough lower priority tasks to bring up the
799  * weighted_cpuload
800  */
801 static inline int above_background_load(void)
802 {
803 	unsigned long cpu;
804 
805 	for_each_online_cpu(cpu) {
806 		if (weighted_cpuload(cpu) >= SCHED_LOAD_SCALE)
807 			return 1;
808 	}
809 	return 0;
810 }
811 
812 struct io_context;			/* See blkdev.h */
813 #define NGROUPS_SMALL		32
814 #define NGROUPS_PER_BLOCK	((unsigned int)(PAGE_SIZE / sizeof(gid_t)))
815 struct group_info {
816 	int ngroups;
817 	atomic_t usage;
818 	gid_t small_block[NGROUPS_SMALL];
819 	int nblocks;
820 	gid_t *blocks[0];
821 };
822 
823 /*
824  * get_group_info() must be called with the owning task locked (via task_lock())
825  * when task != current.  The reason being that the vast majority of callers are
826  * looking at current->group_info, which can not be changed except by the
827  * current task.  Changing current->group_info requires the task lock, too.
828  */
829 #define get_group_info(group_info) do { \
830 	atomic_inc(&(group_info)->usage); \
831 } while (0)
832 
833 #define put_group_info(group_info) do { \
834 	if (atomic_dec_and_test(&(group_info)->usage)) \
835 		groups_free(group_info); \
836 } while (0)
837 
838 extern struct group_info *groups_alloc(int gidsetsize);
839 extern void groups_free(struct group_info *group_info);
840 extern int set_current_groups(struct group_info *group_info);
841 extern int groups_search(struct group_info *group_info, gid_t grp);
842 /* access the groups "array" with this macro */
843 #define GROUP_AT(gi, i) \
844     ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
845 
846 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
847 extern void prefetch_stack(struct task_struct *t);
848 #else
849 static inline void prefetch_stack(struct task_struct *t) { }
850 #endif
851 
852 struct audit_context;		/* See audit.c */
853 struct mempolicy;
854 struct pipe_inode_info;
855 struct uts_namespace;
856 
857 struct rq;
858 struct sched_domain;
859 
860 struct sched_class {
861 	const struct sched_class *next;
862 
863 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int wakeup);
864 	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int sleep);
865 	void (*yield_task) (struct rq *rq);
866 	int  (*select_task_rq)(struct task_struct *p, int sync);
867 
868 	void (*check_preempt_curr) (struct rq *rq, struct task_struct *p);
869 
870 	struct task_struct * (*pick_next_task) (struct rq *rq);
871 	void (*put_prev_task) (struct rq *rq, struct task_struct *p);
872 
873 #ifdef CONFIG_SMP
874 	unsigned long (*load_balance) (struct rq *this_rq, int this_cpu,
875 			struct rq *busiest, unsigned long max_load_move,
876 			struct sched_domain *sd, enum cpu_idle_type idle,
877 			int *all_pinned, int *this_best_prio);
878 
879 	int (*move_one_task) (struct rq *this_rq, int this_cpu,
880 			      struct rq *busiest, struct sched_domain *sd,
881 			      enum cpu_idle_type idle);
882 	void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
883 	void (*post_schedule) (struct rq *this_rq);
884 	void (*task_wake_up) (struct rq *this_rq, struct task_struct *task);
885 #endif
886 
887 	void (*set_curr_task) (struct rq *rq);
888 	void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
889 	void (*task_new) (struct rq *rq, struct task_struct *p);
890 	void (*set_cpus_allowed)(struct task_struct *p, cpumask_t *newmask);
891 
892 	void (*join_domain)(struct rq *rq);
893 	void (*leave_domain)(struct rq *rq);
894 
895 	void (*switched_from) (struct rq *this_rq, struct task_struct *task,
896 			       int running);
897 	void (*switched_to) (struct rq *this_rq, struct task_struct *task,
898 			     int running);
899 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
900 			     int oldprio, int running);
901 };
902 
903 struct load_weight {
904 	unsigned long weight, inv_weight;
905 };
906 
907 /*
908  * CFS stats for a schedulable entity (task, task-group etc)
909  *
910  * Current field usage histogram:
911  *
912  *     4 se->block_start
913  *     4 se->run_node
914  *     4 se->sleep_start
915  *     6 se->load.weight
916  */
917 struct sched_entity {
918 	struct load_weight	load;		/* for load-balancing */
919 	struct rb_node		run_node;
920 	unsigned int		on_rq;
921 
922 	u64			exec_start;
923 	u64			sum_exec_runtime;
924 	u64			vruntime;
925 	u64			prev_sum_exec_runtime;
926 
927 #ifdef CONFIG_SCHEDSTATS
928 	u64			wait_start;
929 	u64			wait_max;
930 	u64			wait_count;
931 	u64			wait_sum;
932 
933 	u64			sleep_start;
934 	u64			sleep_max;
935 	s64			sum_sleep_runtime;
936 
937 	u64			block_start;
938 	u64			block_max;
939 	u64			exec_max;
940 	u64			slice_max;
941 
942 	u64			nr_migrations;
943 	u64			nr_migrations_cold;
944 	u64			nr_failed_migrations_affine;
945 	u64			nr_failed_migrations_running;
946 	u64			nr_failed_migrations_hot;
947 	u64			nr_forced_migrations;
948 	u64			nr_forced2_migrations;
949 
950 	u64			nr_wakeups;
951 	u64			nr_wakeups_sync;
952 	u64			nr_wakeups_migrate;
953 	u64			nr_wakeups_local;
954 	u64			nr_wakeups_remote;
955 	u64			nr_wakeups_affine;
956 	u64			nr_wakeups_affine_attempts;
957 	u64			nr_wakeups_passive;
958 	u64			nr_wakeups_idle;
959 #endif
960 
961 #ifdef CONFIG_FAIR_GROUP_SCHED
962 	struct sched_entity	*parent;
963 	/* rq on which this entity is (to be) queued: */
964 	struct cfs_rq		*cfs_rq;
965 	/* rq "owned" by this entity/group: */
966 	struct cfs_rq		*my_q;
967 #endif
968 };
969 
970 struct sched_rt_entity {
971 	struct list_head run_list;
972 	unsigned int time_slice;
973 	unsigned long timeout;
974 	int nr_cpus_allowed;
975 
976 #ifdef CONFIG_RT_GROUP_SCHED
977 	struct sched_rt_entity	*parent;
978 	/* rq on which this entity is (to be) queued: */
979 	struct rt_rq		*rt_rq;
980 	/* rq "owned" by this entity/group: */
981 	struct rt_rq		*my_q;
982 #endif
983 };
984 
985 struct task_struct {
986 	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
987 	void *stack;
988 	atomic_t usage;
989 	unsigned int flags;	/* per process flags, defined below */
990 	unsigned int ptrace;
991 
992 	int lock_depth;		/* BKL lock depth */
993 
994 #ifdef CONFIG_SMP
995 #ifdef __ARCH_WANT_UNLOCKED_CTXSW
996 	int oncpu;
997 #endif
998 #endif
999 
1000 	int prio, static_prio, normal_prio;
1001 	const struct sched_class *sched_class;
1002 	struct sched_entity se;
1003 	struct sched_rt_entity rt;
1004 
1005 #ifdef CONFIG_PREEMPT_NOTIFIERS
1006 	/* list of struct preempt_notifier: */
1007 	struct hlist_head preempt_notifiers;
1008 #endif
1009 
1010 	/*
1011 	 * fpu_counter contains the number of consecutive context switches
1012 	 * that the FPU is used. If this is over a threshold, the lazy fpu
1013 	 * saving becomes unlazy to save the trap. This is an unsigned char
1014 	 * so that after 256 times the counter wraps and the behavior turns
1015 	 * lazy again; this to deal with bursty apps that only use FPU for
1016 	 * a short time
1017 	 */
1018 	unsigned char fpu_counter;
1019 	s8 oomkilladj; /* OOM kill score adjustment (bit shift). */
1020 #ifdef CONFIG_BLK_DEV_IO_TRACE
1021 	unsigned int btrace_seq;
1022 #endif
1023 
1024 	unsigned int policy;
1025 	cpumask_t cpus_allowed;
1026 
1027 #ifdef CONFIG_PREEMPT_RCU
1028 	int rcu_read_lock_nesting;
1029 	int rcu_flipctr_idx;
1030 #endif /* #ifdef CONFIG_PREEMPT_RCU */
1031 
1032 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1033 	struct sched_info sched_info;
1034 #endif
1035 
1036 	struct list_head tasks;
1037 	/*
1038 	 * ptrace_list/ptrace_children forms the list of my children
1039 	 * that were stolen by a ptracer.
1040 	 */
1041 	struct list_head ptrace_children;
1042 	struct list_head ptrace_list;
1043 
1044 	struct mm_struct *mm, *active_mm;
1045 
1046 /* task state */
1047 	struct linux_binfmt *binfmt;
1048 	int exit_state;
1049 	int exit_code, exit_signal;
1050 	int pdeath_signal;  /*  The signal sent when the parent dies  */
1051 	/* ??? */
1052 	unsigned int personality;
1053 	unsigned did_exec:1;
1054 	pid_t pid;
1055 	pid_t tgid;
1056 
1057 #ifdef CONFIG_CC_STACKPROTECTOR
1058 	/* Canary value for the -fstack-protector gcc feature */
1059 	unsigned long stack_canary;
1060 #endif
1061 	/*
1062 	 * pointers to (original) parent process, youngest child, younger sibling,
1063 	 * older sibling, respectively.  (p->father can be replaced with
1064 	 * p->parent->pid)
1065 	 */
1066 	struct task_struct *real_parent; /* real parent process (when being debugged) */
1067 	struct task_struct *parent;	/* parent process */
1068 	/*
1069 	 * children/sibling forms the list of my children plus the
1070 	 * tasks I'm ptracing.
1071 	 */
1072 	struct list_head children;	/* list of my children */
1073 	struct list_head sibling;	/* linkage in my parent's children list */
1074 	struct task_struct *group_leader;	/* threadgroup leader */
1075 
1076 	/* PID/PID hash table linkage. */
1077 	struct pid_link pids[PIDTYPE_MAX];
1078 	struct list_head thread_group;
1079 
1080 	struct completion *vfork_done;		/* for vfork() */
1081 	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
1082 	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
1083 
1084 	unsigned int rt_priority;
1085 	cputime_t utime, stime, utimescaled, stimescaled;
1086 	cputime_t gtime;
1087 	cputime_t prev_utime, prev_stime;
1088 	unsigned long nvcsw, nivcsw; /* context switch counts */
1089 	struct timespec start_time; 		/* monotonic time */
1090 	struct timespec real_start_time;	/* boot based time */
1091 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1092 	unsigned long min_flt, maj_flt;
1093 
1094   	cputime_t it_prof_expires, it_virt_expires;
1095 	unsigned long long it_sched_expires;
1096 	struct list_head cpu_timers[3];
1097 
1098 /* process credentials */
1099 	uid_t uid,euid,suid,fsuid;
1100 	gid_t gid,egid,sgid,fsgid;
1101 	struct group_info *group_info;
1102 	kernel_cap_t   cap_effective, cap_inheritable, cap_permitted, cap_bset;
1103 	unsigned keep_capabilities:1;
1104 	struct user_struct *user;
1105 #ifdef CONFIG_KEYS
1106 	struct key *request_key_auth;	/* assumed request_key authority */
1107 	struct key *thread_keyring;	/* keyring private to this thread */
1108 	unsigned char jit_keyring;	/* default keyring to attach requested keys to */
1109 #endif
1110 	char comm[TASK_COMM_LEN]; /* executable name excluding path
1111 				     - access with [gs]et_task_comm (which lock
1112 				       it with task_lock())
1113 				     - initialized normally by flush_old_exec */
1114 /* file system info */
1115 	int link_count, total_link_count;
1116 #ifdef CONFIG_SYSVIPC
1117 /* ipc stuff */
1118 	struct sysv_sem sysvsem;
1119 #endif
1120 #ifdef CONFIG_DETECT_SOFTLOCKUP
1121 /* hung task detection */
1122 	unsigned long last_switch_timestamp;
1123 	unsigned long last_switch_count;
1124 #endif
1125 /* CPU-specific state of this task */
1126 	struct thread_struct thread;
1127 /* filesystem information */
1128 	struct fs_struct *fs;
1129 /* open file information */
1130 	struct files_struct *files;
1131 /* namespaces */
1132 	struct nsproxy *nsproxy;
1133 /* signal handlers */
1134 	struct signal_struct *signal;
1135 	struct sighand_struct *sighand;
1136 
1137 	sigset_t blocked, real_blocked;
1138 	sigset_t saved_sigmask;		/* To be restored with TIF_RESTORE_SIGMASK */
1139 	struct sigpending pending;
1140 
1141 	unsigned long sas_ss_sp;
1142 	size_t sas_ss_size;
1143 	int (*notifier)(void *priv);
1144 	void *notifier_data;
1145 	sigset_t *notifier_mask;
1146 #ifdef CONFIG_SECURITY
1147 	void *security;
1148 #endif
1149 	struct audit_context *audit_context;
1150 #ifdef CONFIG_AUDITSYSCALL
1151 	uid_t loginuid;
1152 	unsigned int sessionid;
1153 #endif
1154 	seccomp_t seccomp;
1155 
1156 /* Thread group tracking */
1157    	u32 parent_exec_id;
1158    	u32 self_exec_id;
1159 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
1160 	spinlock_t alloc_lock;
1161 
1162 	/* Protection of the PI data structures: */
1163 	spinlock_t pi_lock;
1164 
1165 #ifdef CONFIG_RT_MUTEXES
1166 	/* PI waiters blocked on a rt_mutex held by this task */
1167 	struct plist_head pi_waiters;
1168 	/* Deadlock detection and priority inheritance handling */
1169 	struct rt_mutex_waiter *pi_blocked_on;
1170 #endif
1171 
1172 #ifdef CONFIG_DEBUG_MUTEXES
1173 	/* mutex deadlock detection */
1174 	struct mutex_waiter *blocked_on;
1175 #endif
1176 #ifdef CONFIG_TRACE_IRQFLAGS
1177 	unsigned int irq_events;
1178 	int hardirqs_enabled;
1179 	unsigned long hardirq_enable_ip;
1180 	unsigned int hardirq_enable_event;
1181 	unsigned long hardirq_disable_ip;
1182 	unsigned int hardirq_disable_event;
1183 	int softirqs_enabled;
1184 	unsigned long softirq_disable_ip;
1185 	unsigned int softirq_disable_event;
1186 	unsigned long softirq_enable_ip;
1187 	unsigned int softirq_enable_event;
1188 	int hardirq_context;
1189 	int softirq_context;
1190 #endif
1191 #ifdef CONFIG_LOCKDEP
1192 # define MAX_LOCK_DEPTH 30UL
1193 	u64 curr_chain_key;
1194 	int lockdep_depth;
1195 	struct held_lock held_locks[MAX_LOCK_DEPTH];
1196 	unsigned int lockdep_recursion;
1197 #endif
1198 
1199 /* journalling filesystem info */
1200 	void *journal_info;
1201 
1202 /* stacked block device info */
1203 	struct bio *bio_list, **bio_tail;
1204 
1205 /* VM state */
1206 	struct reclaim_state *reclaim_state;
1207 
1208 	struct backing_dev_info *backing_dev_info;
1209 
1210 	struct io_context *io_context;
1211 
1212 	unsigned long ptrace_message;
1213 	siginfo_t *last_siginfo; /* For ptrace use.  */
1214 #ifdef CONFIG_TASK_XACCT
1215 /* i/o counters(bytes read/written, #syscalls */
1216 	u64 rchar, wchar, syscr, syscw;
1217 #endif
1218 	struct task_io_accounting ioac;
1219 #if defined(CONFIG_TASK_XACCT)
1220 	u64 acct_rss_mem1;	/* accumulated rss usage */
1221 	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1222 	cputime_t acct_stimexpd;/* stime since last update */
1223 #endif
1224 #ifdef CONFIG_NUMA
1225   	struct mempolicy *mempolicy;
1226 	short il_next;
1227 #endif
1228 #ifdef CONFIG_CPUSETS
1229 	nodemask_t mems_allowed;
1230 	int cpuset_mems_generation;
1231 	int cpuset_mem_spread_rotor;
1232 #endif
1233 #ifdef CONFIG_CGROUPS
1234 	/* Control Group info protected by css_set_lock */
1235 	struct css_set *cgroups;
1236 	/* cg_list protected by css_set_lock and tsk->alloc_lock */
1237 	struct list_head cg_list;
1238 #endif
1239 #ifdef CONFIG_FUTEX
1240 	struct robust_list_head __user *robust_list;
1241 #ifdef CONFIG_COMPAT
1242 	struct compat_robust_list_head __user *compat_robust_list;
1243 #endif
1244 	struct list_head pi_state_list;
1245 	struct futex_pi_state *pi_state_cache;
1246 #endif
1247 	atomic_t fs_excl;	/* holding fs exclusive resources */
1248 	struct rcu_head rcu;
1249 
1250 	/*
1251 	 * cache last used pipe for splice
1252 	 */
1253 	struct pipe_inode_info *splice_pipe;
1254 #ifdef	CONFIG_TASK_DELAY_ACCT
1255 	struct task_delay_info *delays;
1256 #endif
1257 #ifdef CONFIG_FAULT_INJECTION
1258 	int make_it_fail;
1259 #endif
1260 	struct prop_local_single dirties;
1261 #ifdef CONFIG_LATENCYTOP
1262 	int latency_record_count;
1263 	struct latency_record latency_record[LT_SAVECOUNT];
1264 #endif
1265 };
1266 
1267 /*
1268  * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1269  * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1270  * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1271  * values are inverted: lower p->prio value means higher priority.
1272  *
1273  * The MAX_USER_RT_PRIO value allows the actual maximum
1274  * RT priority to be separate from the value exported to
1275  * user-space.  This allows kernel threads to set their
1276  * priority to a value higher than any user task. Note:
1277  * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1278  */
1279 
1280 #define MAX_USER_RT_PRIO	100
1281 #define MAX_RT_PRIO		MAX_USER_RT_PRIO
1282 
1283 #define MAX_PRIO		(MAX_RT_PRIO + 40)
1284 #define DEFAULT_PRIO		(MAX_RT_PRIO + 20)
1285 
1286 static inline int rt_prio(int prio)
1287 {
1288 	if (unlikely(prio < MAX_RT_PRIO))
1289 		return 1;
1290 	return 0;
1291 }
1292 
1293 static inline int rt_task(struct task_struct *p)
1294 {
1295 	return rt_prio(p->prio);
1296 }
1297 
1298 static inline void set_task_session(struct task_struct *tsk, pid_t session)
1299 {
1300 	tsk->signal->__session = session;
1301 }
1302 
1303 static inline void set_task_pgrp(struct task_struct *tsk, pid_t pgrp)
1304 {
1305 	tsk->signal->__pgrp = pgrp;
1306 }
1307 
1308 static inline struct pid *task_pid(struct task_struct *task)
1309 {
1310 	return task->pids[PIDTYPE_PID].pid;
1311 }
1312 
1313 static inline struct pid *task_tgid(struct task_struct *task)
1314 {
1315 	return task->group_leader->pids[PIDTYPE_PID].pid;
1316 }
1317 
1318 static inline struct pid *task_pgrp(struct task_struct *task)
1319 {
1320 	return task->group_leader->pids[PIDTYPE_PGID].pid;
1321 }
1322 
1323 static inline struct pid *task_session(struct task_struct *task)
1324 {
1325 	return task->group_leader->pids[PIDTYPE_SID].pid;
1326 }
1327 
1328 struct pid_namespace;
1329 
1330 /*
1331  * the helpers to get the task's different pids as they are seen
1332  * from various namespaces
1333  *
1334  * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1335  * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1336  *                     current.
1337  * task_xid_nr_ns()  : id seen from the ns specified;
1338  *
1339  * set_task_vxid()   : assigns a virtual id to a task;
1340  *
1341  * see also pid_nr() etc in include/linux/pid.h
1342  */
1343 
1344 static inline pid_t task_pid_nr(struct task_struct *tsk)
1345 {
1346 	return tsk->pid;
1347 }
1348 
1349 pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1350 
1351 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1352 {
1353 	return pid_vnr(task_pid(tsk));
1354 }
1355 
1356 
1357 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1358 {
1359 	return tsk->tgid;
1360 }
1361 
1362 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1363 
1364 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1365 {
1366 	return pid_vnr(task_tgid(tsk));
1367 }
1368 
1369 
1370 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1371 {
1372 	return tsk->signal->__pgrp;
1373 }
1374 
1375 pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1376 
1377 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1378 {
1379 	return pid_vnr(task_pgrp(tsk));
1380 }
1381 
1382 
1383 static inline pid_t task_session_nr(struct task_struct *tsk)
1384 {
1385 	return tsk->signal->__session;
1386 }
1387 
1388 pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1389 
1390 static inline pid_t task_session_vnr(struct task_struct *tsk)
1391 {
1392 	return pid_vnr(task_session(tsk));
1393 }
1394 
1395 
1396 /**
1397  * pid_alive - check that a task structure is not stale
1398  * @p: Task structure to be checked.
1399  *
1400  * Test if a process is not yet dead (at most zombie state)
1401  * If pid_alive fails, then pointers within the task structure
1402  * can be stale and must not be dereferenced.
1403  */
1404 static inline int pid_alive(struct task_struct *p)
1405 {
1406 	return p->pids[PIDTYPE_PID].pid != NULL;
1407 }
1408 
1409 /**
1410  * is_global_init - check if a task structure is init
1411  * @tsk: Task structure to be checked.
1412  *
1413  * Check if a task structure is the first user space task the kernel created.
1414  */
1415 static inline int is_global_init(struct task_struct *tsk)
1416 {
1417 	return tsk->pid == 1;
1418 }
1419 
1420 /*
1421  * is_container_init:
1422  * check whether in the task is init in its own pid namespace.
1423  */
1424 extern int is_container_init(struct task_struct *tsk);
1425 
1426 extern struct pid *cad_pid;
1427 
1428 extern void free_task(struct task_struct *tsk);
1429 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1430 
1431 extern void __put_task_struct(struct task_struct *t);
1432 
1433 static inline void put_task_struct(struct task_struct *t)
1434 {
1435 	if (atomic_dec_and_test(&t->usage))
1436 		__put_task_struct(t);
1437 }
1438 
1439 /*
1440  * Per process flags
1441  */
1442 #define PF_ALIGNWARN	0x00000001	/* Print alignment warning msgs */
1443 					/* Not implemented yet, only for 486*/
1444 #define PF_STARTING	0x00000002	/* being created */
1445 #define PF_EXITING	0x00000004	/* getting shut down */
1446 #define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
1447 #define PF_VCPU		0x00000010	/* I'm a virtual CPU */
1448 #define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
1449 #define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
1450 #define PF_DUMPCORE	0x00000200	/* dumped core */
1451 #define PF_SIGNALED	0x00000400	/* killed by a signal */
1452 #define PF_MEMALLOC	0x00000800	/* Allocating memory */
1453 #define PF_FLUSHER	0x00001000	/* responsible for disk writeback */
1454 #define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
1455 #define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
1456 #define PF_FROZEN	0x00010000	/* frozen for system suspend */
1457 #define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
1458 #define PF_KSWAPD	0x00040000	/* I am kswapd */
1459 #define PF_SWAPOFF	0x00080000	/* I am in swapoff */
1460 #define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
1461 #define PF_BORROWED_MM	0x00200000	/* I am a kthread doing use_mm */
1462 #define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
1463 #define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
1464 #define PF_SPREAD_PAGE	0x01000000	/* Spread page cache over cpuset */
1465 #define PF_SPREAD_SLAB	0x02000000	/* Spread some slab caches over cpuset */
1466 #define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
1467 #define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
1468 #define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezeable */
1469 
1470 /*
1471  * Only the _current_ task can read/write to tsk->flags, but other
1472  * tasks can access tsk->flags in readonly mode for example
1473  * with tsk_used_math (like during threaded core dumping).
1474  * There is however an exception to this rule during ptrace
1475  * or during fork: the ptracer task is allowed to write to the
1476  * child->flags of its traced child (same goes for fork, the parent
1477  * can write to the child->flags), because we're guaranteed the
1478  * child is not running and in turn not changing child->flags
1479  * at the same time the parent does it.
1480  */
1481 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1482 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1483 #define clear_used_math() clear_stopped_child_used_math(current)
1484 #define set_used_math() set_stopped_child_used_math(current)
1485 #define conditional_stopped_child_used_math(condition, child) \
1486 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1487 #define conditional_used_math(condition) \
1488 	conditional_stopped_child_used_math(condition, current)
1489 #define copy_to_stopped_child_used_math(child) \
1490 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1491 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1492 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1493 #define used_math() tsk_used_math(current)
1494 
1495 #ifdef CONFIG_SMP
1496 extern int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask);
1497 #else
1498 static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1499 {
1500 	if (!cpu_isset(0, new_mask))
1501 		return -EINVAL;
1502 	return 0;
1503 }
1504 #endif
1505 
1506 extern unsigned long long sched_clock(void);
1507 
1508 /*
1509  * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
1510  * clock constructed from sched_clock():
1511  */
1512 extern unsigned long long cpu_clock(int cpu);
1513 
1514 extern unsigned long long
1515 task_sched_runtime(struct task_struct *task);
1516 
1517 /* sched_exec is called by processes performing an exec */
1518 #ifdef CONFIG_SMP
1519 extern void sched_exec(void);
1520 #else
1521 #define sched_exec()   {}
1522 #endif
1523 
1524 extern void sched_clock_idle_sleep_event(void);
1525 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1526 
1527 #ifdef CONFIG_HOTPLUG_CPU
1528 extern void idle_task_exit(void);
1529 #else
1530 static inline void idle_task_exit(void) {}
1531 #endif
1532 
1533 extern void sched_idle_next(void);
1534 
1535 #ifdef CONFIG_SCHED_DEBUG
1536 extern unsigned int sysctl_sched_latency;
1537 extern unsigned int sysctl_sched_min_granularity;
1538 extern unsigned int sysctl_sched_wakeup_granularity;
1539 extern unsigned int sysctl_sched_batch_wakeup_granularity;
1540 extern unsigned int sysctl_sched_child_runs_first;
1541 extern unsigned int sysctl_sched_features;
1542 extern unsigned int sysctl_sched_migration_cost;
1543 extern unsigned int sysctl_sched_nr_migrate;
1544 #if defined(CONFIG_FAIR_GROUP_SCHED) && defined(CONFIG_SMP)
1545 extern unsigned int sysctl_sched_min_bal_int_shares;
1546 extern unsigned int sysctl_sched_max_bal_int_shares;
1547 #endif
1548 
1549 int sched_nr_latency_handler(struct ctl_table *table, int write,
1550 		struct file *file, void __user *buffer, size_t *length,
1551 		loff_t *ppos);
1552 #endif
1553 extern unsigned int sysctl_sched_rt_period;
1554 extern int sysctl_sched_rt_runtime;
1555 
1556 extern unsigned int sysctl_sched_compat_yield;
1557 
1558 #ifdef CONFIG_RT_MUTEXES
1559 extern int rt_mutex_getprio(struct task_struct *p);
1560 extern void rt_mutex_setprio(struct task_struct *p, int prio);
1561 extern void rt_mutex_adjust_pi(struct task_struct *p);
1562 #else
1563 static inline int rt_mutex_getprio(struct task_struct *p)
1564 {
1565 	return p->normal_prio;
1566 }
1567 # define rt_mutex_adjust_pi(p)		do { } while (0)
1568 #endif
1569 
1570 extern void set_user_nice(struct task_struct *p, long nice);
1571 extern int task_prio(const struct task_struct *p);
1572 extern int task_nice(const struct task_struct *p);
1573 extern int can_nice(const struct task_struct *p, const int nice);
1574 extern int task_curr(const struct task_struct *p);
1575 extern int idle_cpu(int cpu);
1576 extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1577 extern struct task_struct *idle_task(int cpu);
1578 extern struct task_struct *curr_task(int cpu);
1579 extern void set_curr_task(int cpu, struct task_struct *p);
1580 
1581 void yield(void);
1582 
1583 /*
1584  * The default (Linux) execution domain.
1585  */
1586 extern struct exec_domain	default_exec_domain;
1587 
1588 union thread_union {
1589 	struct thread_info thread_info;
1590 	unsigned long stack[THREAD_SIZE/sizeof(long)];
1591 };
1592 
1593 #ifndef __HAVE_ARCH_KSTACK_END
1594 static inline int kstack_end(void *addr)
1595 {
1596 	/* Reliable end of stack detection:
1597 	 * Some APM bios versions misalign the stack
1598 	 */
1599 	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1600 }
1601 #endif
1602 
1603 extern union thread_union init_thread_union;
1604 extern struct task_struct init_task;
1605 
1606 extern struct   mm_struct init_mm;
1607 
1608 extern struct pid_namespace init_pid_ns;
1609 
1610 /*
1611  * find a task by one of its numerical ids
1612  *
1613  * find_task_by_pid_type_ns():
1614  *      it is the most generic call - it finds a task by all id,
1615  *      type and namespace specified
1616  * find_task_by_pid_ns():
1617  *      finds a task by its pid in the specified namespace
1618  * find_task_by_vpid():
1619  *      finds a task by its virtual pid
1620  * find_task_by_pid():
1621  *      finds a task by its global pid
1622  *
1623  * see also find_pid() etc in include/linux/pid.h
1624  */
1625 
1626 extern struct task_struct *find_task_by_pid_type_ns(int type, int pid,
1627 		struct pid_namespace *ns);
1628 
1629 extern struct task_struct *find_task_by_pid(pid_t nr);
1630 extern struct task_struct *find_task_by_vpid(pid_t nr);
1631 extern struct task_struct *find_task_by_pid_ns(pid_t nr,
1632 		struct pid_namespace *ns);
1633 
1634 extern void __set_special_pids(struct pid *pid);
1635 
1636 /* per-UID process charging. */
1637 extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
1638 static inline struct user_struct *get_uid(struct user_struct *u)
1639 {
1640 	atomic_inc(&u->__count);
1641 	return u;
1642 }
1643 extern void free_uid(struct user_struct *);
1644 extern void switch_uid(struct user_struct *);
1645 extern void release_uids(struct user_namespace *ns);
1646 
1647 #include <asm/current.h>
1648 
1649 extern void do_timer(unsigned long ticks);
1650 
1651 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1652 extern int wake_up_process(struct task_struct *tsk);
1653 extern void wake_up_new_task(struct task_struct *tsk,
1654 				unsigned long clone_flags);
1655 #ifdef CONFIG_SMP
1656  extern void kick_process(struct task_struct *tsk);
1657 #else
1658  static inline void kick_process(struct task_struct *tsk) { }
1659 #endif
1660 extern void sched_fork(struct task_struct *p, int clone_flags);
1661 extern void sched_dead(struct task_struct *p);
1662 
1663 extern int in_group_p(gid_t);
1664 extern int in_egroup_p(gid_t);
1665 
1666 extern void proc_caches_init(void);
1667 extern void flush_signals(struct task_struct *);
1668 extern void ignore_signals(struct task_struct *);
1669 extern void flush_signal_handlers(struct task_struct *, int force_default);
1670 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1671 
1672 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1673 {
1674 	unsigned long flags;
1675 	int ret;
1676 
1677 	spin_lock_irqsave(&tsk->sighand->siglock, flags);
1678 	ret = dequeue_signal(tsk, mask, info);
1679 	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1680 
1681 	return ret;
1682 }
1683 
1684 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1685 			      sigset_t *mask);
1686 extern void unblock_all_signals(void);
1687 extern void release_task(struct task_struct * p);
1688 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1689 extern int force_sigsegv(int, struct task_struct *);
1690 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1691 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1692 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
1693 extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
1694 extern int kill_pgrp(struct pid *pid, int sig, int priv);
1695 extern int kill_pid(struct pid *pid, int sig, int priv);
1696 extern int kill_proc_info(int, struct siginfo *, pid_t);
1697 extern void do_notify_parent(struct task_struct *, int);
1698 extern void force_sig(int, struct task_struct *);
1699 extern void force_sig_specific(int, struct task_struct *);
1700 extern int send_sig(int, struct task_struct *, int);
1701 extern void zap_other_threads(struct task_struct *p);
1702 extern int kill_proc(pid_t, int, int);
1703 extern struct sigqueue *sigqueue_alloc(void);
1704 extern void sigqueue_free(struct sigqueue *);
1705 extern int send_sigqueue(int, struct sigqueue *,  struct task_struct *);
1706 extern int send_group_sigqueue(int, struct sigqueue *,  struct task_struct *);
1707 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
1708 extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1709 
1710 static inline int kill_cad_pid(int sig, int priv)
1711 {
1712 	return kill_pid(cad_pid, sig, priv);
1713 }
1714 
1715 /* These can be the second arg to send_sig_info/send_group_sig_info.  */
1716 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
1717 #define SEND_SIG_PRIV	((struct siginfo *) 1)
1718 #define SEND_SIG_FORCED	((struct siginfo *) 2)
1719 
1720 static inline int is_si_special(const struct siginfo *info)
1721 {
1722 	return info <= SEND_SIG_FORCED;
1723 }
1724 
1725 /* True if we are on the alternate signal stack.  */
1726 
1727 static inline int on_sig_stack(unsigned long sp)
1728 {
1729 	return (sp - current->sas_ss_sp < current->sas_ss_size);
1730 }
1731 
1732 static inline int sas_ss_flags(unsigned long sp)
1733 {
1734 	return (current->sas_ss_size == 0 ? SS_DISABLE
1735 		: on_sig_stack(sp) ? SS_ONSTACK : 0);
1736 }
1737 
1738 /*
1739  * Routines for handling mm_structs
1740  */
1741 extern struct mm_struct * mm_alloc(void);
1742 
1743 /* mmdrop drops the mm and the page tables */
1744 extern void __mmdrop(struct mm_struct *);
1745 static inline void mmdrop(struct mm_struct * mm)
1746 {
1747 	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
1748 		__mmdrop(mm);
1749 }
1750 
1751 /* mmput gets rid of the mappings and all user-space */
1752 extern void mmput(struct mm_struct *);
1753 /* Grab a reference to a task's mm, if it is not already going away */
1754 extern struct mm_struct *get_task_mm(struct task_struct *task);
1755 /* Remove the current tasks stale references to the old mm_struct */
1756 extern void mm_release(struct task_struct *, struct mm_struct *);
1757 
1758 extern int  copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1759 extern void flush_thread(void);
1760 extern void exit_thread(void);
1761 
1762 extern void exit_files(struct task_struct *);
1763 extern void __cleanup_signal(struct signal_struct *);
1764 extern void __cleanup_sighand(struct sighand_struct *);
1765 extern void exit_itimers(struct signal_struct *);
1766 
1767 extern NORET_TYPE void do_group_exit(int);
1768 
1769 extern void daemonize(const char *, ...);
1770 extern int allow_signal(int);
1771 extern int disallow_signal(int);
1772 
1773 extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1774 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1775 struct task_struct *fork_idle(int);
1776 
1777 extern void set_task_comm(struct task_struct *tsk, char *from);
1778 extern char *get_task_comm(char *to, struct task_struct *tsk);
1779 
1780 #ifdef CONFIG_SMP
1781 extern void wait_task_inactive(struct task_struct * p);
1782 #else
1783 #define wait_task_inactive(p)	do { } while (0)
1784 #endif
1785 
1786 #define remove_parent(p)	list_del_init(&(p)->sibling)
1787 #define add_parent(p)		list_add_tail(&(p)->sibling,&(p)->parent->children)
1788 
1789 #define next_task(p)	list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
1790 
1791 #define for_each_process(p) \
1792 	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1793 
1794 /*
1795  * Careful: do_each_thread/while_each_thread is a double loop so
1796  *          'break' will not work as expected - use goto instead.
1797  */
1798 #define do_each_thread(g, t) \
1799 	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1800 
1801 #define while_each_thread(g, t) \
1802 	while ((t = next_thread(t)) != g)
1803 
1804 /* de_thread depends on thread_group_leader not being a pid based check */
1805 #define thread_group_leader(p)	(p == p->group_leader)
1806 
1807 /* Do to the insanities of de_thread it is possible for a process
1808  * to have the pid of the thread group leader without actually being
1809  * the thread group leader.  For iteration through the pids in proc
1810  * all we care about is that we have a task with the appropriate
1811  * pid, we don't actually care if we have the right task.
1812  */
1813 static inline int has_group_leader_pid(struct task_struct *p)
1814 {
1815 	return p->pid == p->tgid;
1816 }
1817 
1818 static inline
1819 int same_thread_group(struct task_struct *p1, struct task_struct *p2)
1820 {
1821 	return p1->tgid == p2->tgid;
1822 }
1823 
1824 static inline struct task_struct *next_thread(const struct task_struct *p)
1825 {
1826 	return list_entry(rcu_dereference(p->thread_group.next),
1827 			  struct task_struct, thread_group);
1828 }
1829 
1830 static inline int thread_group_empty(struct task_struct *p)
1831 {
1832 	return list_empty(&p->thread_group);
1833 }
1834 
1835 #define delay_group_leader(p) \
1836 		(thread_group_leader(p) && !thread_group_empty(p))
1837 
1838 /*
1839  * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
1840  * subscriptions and synchronises with wait4().  Also used in procfs.  Also
1841  * pins the final release of task.io_context.  Also protects ->cpuset and
1842  * ->cgroup.subsys[].
1843  *
1844  * Nests both inside and outside of read_lock(&tasklist_lock).
1845  * It must not be nested with write_lock_irq(&tasklist_lock),
1846  * neither inside nor outside.
1847  */
1848 static inline void task_lock(struct task_struct *p)
1849 {
1850 	spin_lock(&p->alloc_lock);
1851 }
1852 
1853 static inline void task_unlock(struct task_struct *p)
1854 {
1855 	spin_unlock(&p->alloc_lock);
1856 }
1857 
1858 extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
1859 							unsigned long *flags);
1860 
1861 static inline void unlock_task_sighand(struct task_struct *tsk,
1862 						unsigned long *flags)
1863 {
1864 	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
1865 }
1866 
1867 #ifndef __HAVE_THREAD_FUNCTIONS
1868 
1869 #define task_thread_info(task)	((struct thread_info *)(task)->stack)
1870 #define task_stack_page(task)	((task)->stack)
1871 
1872 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
1873 {
1874 	*task_thread_info(p) = *task_thread_info(org);
1875 	task_thread_info(p)->task = p;
1876 }
1877 
1878 static inline unsigned long *end_of_stack(struct task_struct *p)
1879 {
1880 	return (unsigned long *)(task_thread_info(p) + 1);
1881 }
1882 
1883 #endif
1884 
1885 /* set thread flags in other task's structures
1886  * - see asm/thread_info.h for TIF_xxxx flags available
1887  */
1888 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1889 {
1890 	set_ti_thread_flag(task_thread_info(tsk), flag);
1891 }
1892 
1893 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1894 {
1895 	clear_ti_thread_flag(task_thread_info(tsk), flag);
1896 }
1897 
1898 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1899 {
1900 	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1901 }
1902 
1903 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1904 {
1905 	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1906 }
1907 
1908 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1909 {
1910 	return test_ti_thread_flag(task_thread_info(tsk), flag);
1911 }
1912 
1913 static inline void set_tsk_need_resched(struct task_struct *tsk)
1914 {
1915 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1916 }
1917 
1918 static inline void clear_tsk_need_resched(struct task_struct *tsk)
1919 {
1920 	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1921 }
1922 
1923 static inline int signal_pending(struct task_struct *p)
1924 {
1925 	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1926 }
1927 
1928 extern int __fatal_signal_pending(struct task_struct *p);
1929 
1930 static inline int fatal_signal_pending(struct task_struct *p)
1931 {
1932 	return signal_pending(p) && __fatal_signal_pending(p);
1933 }
1934 
1935 static inline int need_resched(void)
1936 {
1937 	return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1938 }
1939 
1940 /*
1941  * cond_resched() and cond_resched_lock(): latency reduction via
1942  * explicit rescheduling in places that are safe. The return
1943  * value indicates whether a reschedule was done in fact.
1944  * cond_resched_lock() will drop the spinlock before scheduling,
1945  * cond_resched_softirq() will enable bhs before scheduling.
1946  */
1947 #ifdef CONFIG_PREEMPT
1948 static inline int cond_resched(void)
1949 {
1950 	return 0;
1951 }
1952 #else
1953 extern int _cond_resched(void);
1954 static inline int cond_resched(void)
1955 {
1956 	return _cond_resched();
1957 }
1958 #endif
1959 extern int cond_resched_lock(spinlock_t * lock);
1960 extern int cond_resched_softirq(void);
1961 
1962 /*
1963  * Does a critical section need to be broken due to another
1964  * task waiting?: (technically does not depend on CONFIG_PREEMPT,
1965  * but a general need for low latency)
1966  */
1967 static inline int spin_needbreak(spinlock_t *lock)
1968 {
1969 #ifdef CONFIG_PREEMPT
1970 	return spin_is_contended(lock);
1971 #else
1972 	return 0;
1973 #endif
1974 }
1975 
1976 /*
1977  * Reevaluate whether the task has signals pending delivery.
1978  * Wake the task if so.
1979  * This is required every time the blocked sigset_t changes.
1980  * callers must hold sighand->siglock.
1981  */
1982 extern void recalc_sigpending_and_wake(struct task_struct *t);
1983 extern void recalc_sigpending(void);
1984 
1985 extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1986 
1987 /*
1988  * Wrappers for p->thread_info->cpu access. No-op on UP.
1989  */
1990 #ifdef CONFIG_SMP
1991 
1992 static inline unsigned int task_cpu(const struct task_struct *p)
1993 {
1994 	return task_thread_info(p)->cpu;
1995 }
1996 
1997 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
1998 
1999 #else
2000 
2001 static inline unsigned int task_cpu(const struct task_struct *p)
2002 {
2003 	return 0;
2004 }
2005 
2006 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2007 {
2008 }
2009 
2010 #endif /* CONFIG_SMP */
2011 
2012 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
2013 extern void arch_pick_mmap_layout(struct mm_struct *mm);
2014 #else
2015 static inline void arch_pick_mmap_layout(struct mm_struct *mm)
2016 {
2017 	mm->mmap_base = TASK_UNMAPPED_BASE;
2018 	mm->get_unmapped_area = arch_get_unmapped_area;
2019 	mm->unmap_area = arch_unmap_area;
2020 }
2021 #endif
2022 
2023 extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
2024 extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
2025 
2026 extern int sched_mc_power_savings, sched_smt_power_savings;
2027 
2028 extern void normalize_rt_tasks(void);
2029 
2030 #ifdef CONFIG_GROUP_SCHED
2031 
2032 extern struct task_group init_task_group;
2033 
2034 extern struct task_group *sched_create_group(void);
2035 extern void sched_destroy_group(struct task_group *tg);
2036 extern void sched_move_task(struct task_struct *tsk);
2037 #ifdef CONFIG_FAIR_GROUP_SCHED
2038 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2039 extern unsigned long sched_group_shares(struct task_group *tg);
2040 #endif
2041 #ifdef CONFIG_RT_GROUP_SCHED
2042 extern int sched_group_set_rt_runtime(struct task_group *tg,
2043 				      long rt_runtime_us);
2044 extern long sched_group_rt_runtime(struct task_group *tg);
2045 #endif
2046 #endif
2047 
2048 #ifdef CONFIG_TASK_XACCT
2049 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2050 {
2051 	tsk->rchar += amt;
2052 }
2053 
2054 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2055 {
2056 	tsk->wchar += amt;
2057 }
2058 
2059 static inline void inc_syscr(struct task_struct *tsk)
2060 {
2061 	tsk->syscr++;
2062 }
2063 
2064 static inline void inc_syscw(struct task_struct *tsk)
2065 {
2066 	tsk->syscw++;
2067 }
2068 #else
2069 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2070 {
2071 }
2072 
2073 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2074 {
2075 }
2076 
2077 static inline void inc_syscr(struct task_struct *tsk)
2078 {
2079 }
2080 
2081 static inline void inc_syscw(struct task_struct *tsk)
2082 {
2083 }
2084 #endif
2085 
2086 #ifdef CONFIG_SMP
2087 void migration_init(void);
2088 #else
2089 static inline void migration_init(void)
2090 {
2091 }
2092 #endif
2093 
2094 #ifndef TASK_SIZE_OF
2095 #define TASK_SIZE_OF(tsk)	TASK_SIZE
2096 #endif
2097 
2098 #endif /* __KERNEL__ */
2099 
2100 #endif
2101