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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef _LINUX_SCHED_H
2#define _LINUX_SCHED_H
3
4#include <asm/param.h> /* for HZ */
5
6#include <linux/config.h>
7#include <linux/capability.h>
8#include <linux/threads.h>
9#include <linux/kernel.h>
10#include <linux/types.h>
11#include <linux/timex.h>
12#include <linux/jiffies.h>
13#include <linux/rbtree.h>
14#include <linux/thread_info.h>
15#include <linux/cpumask.h>
16#include <linux/errno.h>
17#include <linux/nodemask.h>
18
19#include <asm/system.h>
20#include <asm/semaphore.h>
21#include <asm/page.h>
22#include <asm/ptrace.h>
23#include <asm/mmu.h>
24#include <asm/cputime.h>
25
26#include <linux/smp.h>
27#include <linux/sem.h>
28#include <linux/signal.h>
29#include <linux/securebits.h>
30#include <linux/fs_struct.h>
31#include <linux/compiler.h>
32#include <linux/completion.h>
33#include <linux/pid.h>
34#include <linux/percpu.h>
35#include <linux/topology.h>
36#include <linux/seccomp.h>
Ingo Molnare56d0902006-01-08 01:01:37 -080037#include <linux/rcupdate.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
H. J. Lu36d57ac2005-09-06 15:16:49 -070039#include <linux/auxvec.h> /* For AT_VECTOR_SIZE */
40
Linus Torvalds1da177e2005-04-16 15:20:36 -070041struct exec_domain;
42
43/*
44 * cloning flags:
45 */
46#define CSIGNAL 0x000000ff /* signal mask to be sent at exit */
47#define CLONE_VM 0x00000100 /* set if VM shared between processes */
48#define CLONE_FS 0x00000200 /* set if fs info shared between processes */
49#define CLONE_FILES 0x00000400 /* set if open files shared between processes */
50#define CLONE_SIGHAND 0x00000800 /* set if signal handlers and blocked signals shared */
51#define CLONE_PTRACE 0x00002000 /* set if we want to let tracing continue on the child too */
52#define CLONE_VFORK 0x00004000 /* set if the parent wants the child to wake it up on mm_release */
53#define CLONE_PARENT 0x00008000 /* set if we want to have the same parent as the cloner */
54#define CLONE_THREAD 0x00010000 /* Same thread group? */
55#define CLONE_NEWNS 0x00020000 /* New namespace group? */
56#define CLONE_SYSVSEM 0x00040000 /* share system V SEM_UNDO semantics */
57#define CLONE_SETTLS 0x00080000 /* create a new TLS for the child */
58#define CLONE_PARENT_SETTID 0x00100000 /* set the TID in the parent */
59#define CLONE_CHILD_CLEARTID 0x00200000 /* clear the TID in the child */
60#define CLONE_DETACHED 0x00400000 /* Unused, ignored */
61#define CLONE_UNTRACED 0x00800000 /* set if the tracing process can't force CLONE_PTRACE on this clone */
62#define CLONE_CHILD_SETTID 0x01000000 /* set the TID in the child */
63#define CLONE_STOPPED 0x02000000 /* Start in stopped state */
64
65/*
66 * List of flags we want to share for kernel threads,
67 * if only because they are not used by them anyway.
68 */
69#define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
70
71/*
72 * These are the constant used to fake the fixed-point load-average
73 * counting. Some notes:
74 * - 11 bit fractions expand to 22 bits by the multiplies: this gives
75 * a load-average precision of 10 bits integer + 11 bits fractional
76 * - if you want to count load-averages more often, you need more
77 * precision, or rounding will get you. With 2-second counting freq,
78 * the EXP_n values would be 1981, 2034 and 2043 if still using only
79 * 11 bit fractions.
80 */
81extern unsigned long avenrun[]; /* Load averages */
82
83#define FSHIFT 11 /* nr of bits of precision */
84#define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
85#define LOAD_FREQ (5*HZ) /* 5 sec intervals */
86#define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
87#define EXP_5 2014 /* 1/exp(5sec/5min) */
88#define EXP_15 2037 /* 1/exp(5sec/15min) */
89
90#define CALC_LOAD(load,exp,n) \
91 load *= exp; \
92 load += n*(FIXED_1-exp); \
93 load >>= FSHIFT;
94
95extern unsigned long total_forks;
96extern int nr_threads;
97extern int last_pid;
98DECLARE_PER_CPU(unsigned long, process_counts);
99extern int nr_processes(void);
100extern unsigned long nr_running(void);
101extern unsigned long nr_uninterruptible(void);
102extern unsigned long nr_iowait(void);
103
104#include <linux/time.h>
105#include <linux/param.h>
106#include <linux/resource.h>
107#include <linux/timer.h>
Thomas Gleixner2ff678b2006-01-09 20:52:34 -0800108#include <linux/hrtimer.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109
110#include <asm/processor.h>
111
Linus Torvalds4a8342d2005-09-29 15:18:21 -0700112/*
113 * Task state bitmask. NOTE! These bits are also
114 * encoded in fs/proc/array.c: get_task_state().
115 *
116 * We have two separate sets of flags: task->state
117 * is about runnability, while task->exit_state are
118 * about the task exiting. Confusing, but this way
119 * modifying one set can't modify the other one by
120 * mistake.
121 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122#define TASK_RUNNING 0
123#define TASK_INTERRUPTIBLE 1
124#define TASK_UNINTERRUPTIBLE 2
Linus Torvalds4a8342d2005-09-29 15:18:21 -0700125#define TASK_STOPPED 4
126#define TASK_TRACED 8
127/* in tsk->exit_state */
128#define EXIT_ZOMBIE 16
129#define EXIT_DEAD 32
130/* in tsk->state again */
131#define TASK_NONINTERACTIVE 64
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132
133#define __set_task_state(tsk, state_value) \
134 do { (tsk)->state = (state_value); } while (0)
135#define set_task_state(tsk, state_value) \
136 set_mb((tsk)->state, (state_value))
137
Andrew Morton498d0c52005-09-13 01:25:14 -0700138/*
139 * set_current_state() includes a barrier so that the write of current->state
140 * is correctly serialised wrt the caller's subsequent test of whether to
141 * actually sleep:
142 *
143 * set_current_state(TASK_UNINTERRUPTIBLE);
144 * if (do_i_need_to_sleep())
145 * schedule();
146 *
147 * If the caller does not need such serialisation then use __set_current_state()
148 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149#define __set_current_state(state_value) \
150 do { current->state = (state_value); } while (0)
151#define set_current_state(state_value) \
152 set_mb(current->state, (state_value))
153
154/* Task command name length */
155#define TASK_COMM_LEN 16
156
157/*
158 * Scheduling policies
159 */
160#define SCHED_NORMAL 0
161#define SCHED_FIFO 1
162#define SCHED_RR 2
163
164struct sched_param {
165 int sched_priority;
166};
167
168#ifdef __KERNEL__
169
170#include <linux/spinlock.h>
171
172/*
173 * This serializes "schedule()" and also protects
174 * the run-queue from deletions/modifications (but
175 * _adding_ to the beginning of the run-queue has
176 * a separate lock).
177 */
178extern rwlock_t tasklist_lock;
179extern spinlock_t mmlist_lock;
180
181typedef struct task_struct task_t;
182
183extern void sched_init(void);
184extern void sched_init_smp(void);
185extern void init_idle(task_t *idle, int cpu);
186
187extern cpumask_t nohz_cpu_mask;
188
189extern void show_state(void);
190extern void show_regs(struct pt_regs *);
191
192/*
193 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
194 * task), SP is the stack pointer of the first frame that should be shown in the back
195 * trace (or NULL if the entire call-chain of the task should be shown).
196 */
197extern void show_stack(struct task_struct *task, unsigned long *sp);
198
199void io_schedule(void);
200long io_schedule_timeout(long timeout);
201
202extern void cpu_init (void);
203extern void trap_init(void);
204extern void update_process_times(int user);
205extern void scheduler_tick(void);
206
Ingo Molnar8446f1d2005-09-06 15:16:27 -0700207#ifdef CONFIG_DETECT_SOFTLOCKUP
208extern void softlockup_tick(struct pt_regs *regs);
209extern void spawn_softlockup_task(void);
210extern void touch_softlockup_watchdog(void);
211#else
212static inline void softlockup_tick(struct pt_regs *regs)
213{
214}
215static inline void spawn_softlockup_task(void)
216{
217}
218static inline void touch_softlockup_watchdog(void)
219{
220}
221#endif
222
223
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224/* Attach to any functions which should be ignored in wchan output. */
225#define __sched __attribute__((__section__(".sched.text")))
226/* Is this address in the __sched functions? */
227extern int in_sched_functions(unsigned long addr);
228
229#define MAX_SCHEDULE_TIMEOUT LONG_MAX
230extern signed long FASTCALL(schedule_timeout(signed long timeout));
Nishanth Aravamudan64ed93a2005-09-10 00:27:21 -0700231extern signed long schedule_timeout_interruptible(signed long timeout);
232extern signed long schedule_timeout_uninterruptible(signed long timeout);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233asmlinkage void schedule(void);
234
235struct namespace;
236
237/* Maximum number of active map areas.. This is a random (large) number */
238#define DEFAULT_MAX_MAP_COUNT 65536
239
240extern int sysctl_max_map_count;
241
242#include <linux/aio.h>
243
244extern unsigned long
245arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
246 unsigned long, unsigned long);
247extern unsigned long
248arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
249 unsigned long len, unsigned long pgoff,
250 unsigned long flags);
Wolfgang Wander1363c3c2005-06-21 17:14:49 -0700251extern void arch_unmap_area(struct mm_struct *, unsigned long);
252extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700254#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
255/*
256 * The mm counters are not protected by its page_table_lock,
257 * so must be incremented atomically.
258 */
Christoph Lameterd3cb4872006-01-06 00:11:20 -0800259#define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
260#define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
261#define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
262#define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
263#define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
264typedef atomic_long_t mm_counter_t;
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700265
266#else /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
267/*
268 * The mm counters are protected by its page_table_lock,
269 * so can be incremented directly.
270 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271#define set_mm_counter(mm, member, value) (mm)->_##member = (value)
272#define get_mm_counter(mm, member) ((mm)->_##member)
273#define add_mm_counter(mm, member, value) (mm)->_##member += (value)
274#define inc_mm_counter(mm, member) (mm)->_##member++
275#define dec_mm_counter(mm, member) (mm)->_##member--
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700276typedef unsigned long mm_counter_t;
Hugh Dickins42946212005-10-29 18:16:05 -0700277
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700278#endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
279
280#define get_mm_rss(mm) \
281 (get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
Hugh Dickins365e9c872005-10-29 18:16:18 -0700282#define update_hiwater_rss(mm) do { \
283 unsigned long _rss = get_mm_rss(mm); \
284 if ((mm)->hiwater_rss < _rss) \
285 (mm)->hiwater_rss = _rss; \
286} while (0)
287#define update_hiwater_vm(mm) do { \
288 if ((mm)->hiwater_vm < (mm)->total_vm) \
289 (mm)->hiwater_vm = (mm)->total_vm; \
290} while (0)
291
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292struct mm_struct {
293 struct vm_area_struct * mmap; /* list of VMAs */
294 struct rb_root mm_rb;
295 struct vm_area_struct * mmap_cache; /* last find_vma result */
296 unsigned long (*get_unmapped_area) (struct file *filp,
297 unsigned long addr, unsigned long len,
298 unsigned long pgoff, unsigned long flags);
Wolfgang Wander1363c3c2005-06-21 17:14:49 -0700299 void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
300 unsigned long mmap_base; /* base of mmap area */
301 unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */
302 unsigned long free_area_cache; /* first hole of size cached_hole_size or larger */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303 pgd_t * pgd;
304 atomic_t mm_users; /* How many users with user space? */
305 atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */
306 int map_count; /* number of VMAs */
307 struct rw_semaphore mmap_sem;
308 spinlock_t page_table_lock; /* Protects page tables and some counters */
309
310 struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung
311 * together off init_mm.mmlist, and are protected
312 * by mmlist_lock
313 */
314
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700315 /* Special counters, in some configurations protected by the
316 * page_table_lock, in other configurations by being atomic.
317 */
Hugh Dickins42946212005-10-29 18:16:05 -0700318 mm_counter_t _file_rss;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319 mm_counter_t _anon_rss;
320
Hugh Dickinsf4499522005-10-29 18:16:19 -0700321 unsigned long hiwater_rss; /* High-watermark of RSS usage */
322 unsigned long hiwater_vm; /* High-water virtual memory usage */
323
324 unsigned long total_vm, locked_vm, shared_vm, exec_vm;
325 unsigned long stack_vm, reserved_vm, def_flags, nr_ptes;
326 unsigned long start_code, end_code, start_data, end_data;
327 unsigned long start_brk, brk, start_stack;
328 unsigned long arg_start, arg_end, env_start, env_end;
329
H. J. Lu36d57ac2005-09-06 15:16:49 -0700330 unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331
Alan Coxd6e71142005-06-23 00:09:43 -0700332 unsigned dumpable:2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700333 cpumask_t cpu_vm_mask;
334
335 /* Architecture-specific MM context */
336 mm_context_t context;
337
338 /* Token based thrashing protection. */
339 unsigned long swap_token_time;
340 char recent_pagein;
341
342 /* coredumping support */
343 int core_waiters;
344 struct completion *core_startup_done, core_done;
345
346 /* aio bits */
347 rwlock_t ioctx_list_lock;
348 struct kioctx *ioctx_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349};
350
351struct sighand_struct {
352 atomic_t count;
353 struct k_sigaction action[_NSIG];
354 spinlock_t siglock;
Ingo Molnare56d0902006-01-08 01:01:37 -0800355 struct rcu_head rcu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356};
357
Ingo Molnare56d0902006-01-08 01:01:37 -0800358extern void sighand_free_cb(struct rcu_head *rhp);
359
360static inline void sighand_free(struct sighand_struct *sp)
361{
362 call_rcu(&sp->rcu, sighand_free_cb);
363}
364
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365/*
366 * NOTE! "signal_struct" does not have it's own
367 * locking, because a shared signal_struct always
368 * implies a shared sighand_struct, so locking
369 * sighand_struct is always a proper superset of
370 * the locking of signal_struct.
371 */
372struct signal_struct {
373 atomic_t count;
374 atomic_t live;
375
376 wait_queue_head_t wait_chldexit; /* for wait4() */
377
378 /* current thread group signal load-balancing target: */
379 task_t *curr_target;
380
381 /* shared signal handling: */
382 struct sigpending shared_pending;
383
384 /* thread group exit support */
385 int group_exit_code;
386 /* overloaded:
387 * - notify group_exit_task when ->count is equal to notify_count
388 * - everyone except group_exit_task is stopped during signal delivery
389 * of fatal signals, group_exit_task processes the signal.
390 */
391 struct task_struct *group_exit_task;
392 int notify_count;
393
394 /* thread group stop support, overloads group_exit_code too */
395 int group_stop_count;
396 unsigned int flags; /* see SIGNAL_* flags below */
397
398 /* POSIX.1b Interval Timers */
399 struct list_head posix_timers;
400
401 /* ITIMER_REAL timer for the process */
Thomas Gleixner2ff678b2006-01-09 20:52:34 -0800402 struct hrtimer real_timer;
403 ktime_t it_real_incr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404
405 /* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
406 cputime_t it_prof_expires, it_virt_expires;
407 cputime_t it_prof_incr, it_virt_incr;
408
409 /* job control IDs */
410 pid_t pgrp;
411 pid_t tty_old_pgrp;
412 pid_t session;
413 /* boolean value for session group leader */
414 int leader;
415
416 struct tty_struct *tty; /* NULL if no tty */
417
418 /*
419 * Cumulative resource counters for dead threads in the group,
420 * and for reaped dead child processes forked by this group.
421 * Live threads maintain their own counters and add to these
422 * in __exit_signal, except for the group leader.
423 */
424 cputime_t utime, stime, cutime, cstime;
425 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
426 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
427
428 /*
429 * Cumulative ns of scheduled CPU time for dead threads in the
430 * group, not including a zombie group leader. (This only differs
431 * from jiffies_to_ns(utime + stime) if sched_clock uses something
432 * other than jiffies.)
433 */
434 unsigned long long sched_time;
435
436 /*
437 * We don't bother to synchronize most readers of this at all,
438 * because there is no reader checking a limit that actually needs
439 * to get both rlim_cur and rlim_max atomically, and either one
440 * alone is a single word that can safely be read normally.
441 * getrlimit/setrlimit use task_lock(current->group_leader) to
442 * protect this instead of the siglock, because they really
443 * have no need to disable irqs.
444 */
445 struct rlimit rlim[RLIM_NLIMITS];
446
447 struct list_head cpu_timers[3];
448
449 /* keep the process-shared keyrings here so that they do the right
450 * thing in threads created with CLONE_THREAD */
451#ifdef CONFIG_KEYS
452 struct key *session_keyring; /* keyring inherited over fork */
453 struct key *process_keyring; /* keyring private to this process */
454#endif
455};
456
Nick Piggin4866cde2005-06-25 14:57:23 -0700457/* Context switch must be unlocked if interrupts are to be enabled */
458#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
459# define __ARCH_WANT_UNLOCKED_CTXSW
460#endif
461
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462/*
463 * Bits in flags field of signal_struct.
464 */
465#define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */
466#define SIGNAL_STOP_DEQUEUED 0x00000002 /* stop signal dequeued */
467#define SIGNAL_STOP_CONTINUED 0x00000004 /* SIGCONT since WCONTINUED reap */
468#define SIGNAL_GROUP_EXIT 0x00000008 /* group exit in progress */
469
470
471/*
472 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
473 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL tasks are
474 * in the range MAX_RT_PRIO..MAX_PRIO-1. Priority values
475 * are inverted: lower p->prio value means higher priority.
476 *
477 * The MAX_USER_RT_PRIO value allows the actual maximum
478 * RT priority to be separate from the value exported to
479 * user-space. This allows kernel threads to set their
480 * priority to a value higher than any user task. Note:
481 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
482 */
483
484#define MAX_USER_RT_PRIO 100
485#define MAX_RT_PRIO MAX_USER_RT_PRIO
486
487#define MAX_PRIO (MAX_RT_PRIO + 40)
488
489#define rt_task(p) (unlikely((p)->prio < MAX_RT_PRIO))
490
491/*
492 * Some day this will be a full-fledged user tracking system..
493 */
494struct user_struct {
495 atomic_t __count; /* reference count */
496 atomic_t processes; /* How many processes does this user have? */
497 atomic_t files; /* How many open files does this user have? */
498 atomic_t sigpending; /* How many pending signals does this user have? */
Robert Love0eeca282005-07-12 17:06:03 -0400499#ifdef CONFIG_INOTIFY
500 atomic_t inotify_watches; /* How many inotify watches does this user have? */
501 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */
502#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700503 /* protected by mq_lock */
504 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
505 unsigned long locked_shm; /* How many pages of mlocked shm ? */
506
507#ifdef CONFIG_KEYS
508 struct key *uid_keyring; /* UID specific keyring */
509 struct key *session_keyring; /* UID's default session keyring */
510#endif
511
512 /* Hash table maintenance information */
513 struct list_head uidhash_list;
514 uid_t uid;
515};
516
517extern struct user_struct *find_user(uid_t);
518
519extern struct user_struct root_user;
520#define INIT_USER (&root_user)
521
522typedef struct prio_array prio_array_t;
523struct backing_dev_info;
524struct reclaim_state;
525
526#ifdef CONFIG_SCHEDSTATS
527struct sched_info {
528 /* cumulative counters */
529 unsigned long cpu_time, /* time spent on the cpu */
530 run_delay, /* time spent waiting on a runqueue */
531 pcnt; /* # of timeslices run on this cpu */
532
533 /* timestamps */
534 unsigned long last_arrival, /* when we last ran on a cpu */
535 last_queued; /* when we were last queued to run */
536};
537
538extern struct file_operations proc_schedstat_operations;
539#endif
540
541enum idle_type
542{
543 SCHED_IDLE,
544 NOT_IDLE,
545 NEWLY_IDLE,
546 MAX_IDLE_TYPES
547};
548
549/*
550 * sched-domains (multiprocessor balancing) declarations:
551 */
552#ifdef CONFIG_SMP
553#define SCHED_LOAD_SCALE 128UL /* increase resolution of load */
554
555#define SD_LOAD_BALANCE 1 /* Do load balancing on this domain. */
556#define SD_BALANCE_NEWIDLE 2 /* Balance when about to become idle */
557#define SD_BALANCE_EXEC 4 /* Balance on exec */
Nick Piggin147cbb42005-06-25 14:57:19 -0700558#define SD_BALANCE_FORK 8 /* Balance on fork, clone */
559#define SD_WAKE_IDLE 16 /* Wake to idle CPU on task wakeup */
560#define SD_WAKE_AFFINE 32 /* Wake task to waking CPU */
561#define SD_WAKE_BALANCE 64 /* Perform balancing at task wakeup */
562#define SD_SHARE_CPUPOWER 128 /* Domain members share cpu power */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563
564struct sched_group {
565 struct sched_group *next; /* Must be a circular list */
566 cpumask_t cpumask;
567
568 /*
569 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
570 * single CPU. This is read only (except for setup, hotplug CPU).
571 */
572 unsigned long cpu_power;
573};
574
575struct sched_domain {
576 /* These fields must be setup */
577 struct sched_domain *parent; /* top domain must be null terminated */
578 struct sched_group *groups; /* the balancing groups of the domain */
579 cpumask_t span; /* span of all CPUs in this domain */
580 unsigned long min_interval; /* Minimum balance interval ms */
581 unsigned long max_interval; /* Maximum balance interval ms */
582 unsigned int busy_factor; /* less balancing by factor if busy */
583 unsigned int imbalance_pct; /* No balance until over watermark */
584 unsigned long long cache_hot_time; /* Task considered cache hot (ns) */
585 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */
586 unsigned int per_cpu_gain; /* CPU % gained by adding domain cpus */
Nick Piggin78979862005-06-25 14:57:13 -0700587 unsigned int busy_idx;
588 unsigned int idle_idx;
589 unsigned int newidle_idx;
590 unsigned int wake_idx;
Nick Piggin147cbb42005-06-25 14:57:19 -0700591 unsigned int forkexec_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700592 int flags; /* See SD_* */
593
594 /* Runtime fields. */
595 unsigned long last_balance; /* init to jiffies. units in jiffies */
596 unsigned int balance_interval; /* initialise to 1. units in ms. */
597 unsigned int nr_balance_failed; /* initialise to 0 */
598
599#ifdef CONFIG_SCHEDSTATS
600 /* load_balance() stats */
601 unsigned long lb_cnt[MAX_IDLE_TYPES];
602 unsigned long lb_failed[MAX_IDLE_TYPES];
603 unsigned long lb_balanced[MAX_IDLE_TYPES];
604 unsigned long lb_imbalance[MAX_IDLE_TYPES];
605 unsigned long lb_gained[MAX_IDLE_TYPES];
606 unsigned long lb_hot_gained[MAX_IDLE_TYPES];
607 unsigned long lb_nobusyg[MAX_IDLE_TYPES];
608 unsigned long lb_nobusyq[MAX_IDLE_TYPES];
609
610 /* Active load balancing */
611 unsigned long alb_cnt;
612 unsigned long alb_failed;
613 unsigned long alb_pushed;
614
Nick Piggin68767a02005-06-25 14:57:20 -0700615 /* SD_BALANCE_EXEC stats */
616 unsigned long sbe_cnt;
617 unsigned long sbe_balanced;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618 unsigned long sbe_pushed;
619
Nick Piggin68767a02005-06-25 14:57:20 -0700620 /* SD_BALANCE_FORK stats */
621 unsigned long sbf_cnt;
622 unsigned long sbf_balanced;
623 unsigned long sbf_pushed;
624
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 /* try_to_wake_up() stats */
626 unsigned long ttwu_wake_remote;
627 unsigned long ttwu_move_affine;
628 unsigned long ttwu_move_balance;
629#endif
630};
631
Dinakar Guniguntala1a20ff22005-06-25 14:57:33 -0700632extern void partition_sched_domains(cpumask_t *partition1,
633 cpumask_t *partition2);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634#endif /* CONFIG_SMP */
635
636
637struct io_context; /* See blkdev.h */
638void exit_io_context(void);
639struct cpuset;
640
641#define NGROUPS_SMALL 32
642#define NGROUPS_PER_BLOCK ((int)(PAGE_SIZE / sizeof(gid_t)))
643struct group_info {
644 int ngroups;
645 atomic_t usage;
646 gid_t small_block[NGROUPS_SMALL];
647 int nblocks;
648 gid_t *blocks[0];
649};
650
651/*
652 * get_group_info() must be called with the owning task locked (via task_lock())
653 * when task != current. The reason being that the vast majority of callers are
654 * looking at current->group_info, which can not be changed except by the
655 * current task. Changing current->group_info requires the task lock, too.
656 */
657#define get_group_info(group_info) do { \
658 atomic_inc(&(group_info)->usage); \
659} while (0)
660
661#define put_group_info(group_info) do { \
662 if (atomic_dec_and_test(&(group_info)->usage)) \
663 groups_free(group_info); \
664} while (0)
665
David Howells3e301482005-06-23 22:00:56 -0700666extern struct group_info *groups_alloc(int gidsetsize);
667extern void groups_free(struct group_info *group_info);
668extern int set_current_groups(struct group_info *group_info);
669extern int groups_search(struct group_info *group_info, gid_t grp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700670/* access the groups "array" with this macro */
671#define GROUP_AT(gi, i) \
672 ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
673
Chen, Kenneth W383f2832005-09-09 13:02:02 -0700674#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
675extern void prefetch_stack(struct task_struct*);
676#else
677static inline void prefetch_stack(struct task_struct *t) { }
678#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700679
680struct audit_context; /* See audit.c */
681struct mempolicy;
682
683struct task_struct {
684 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
685 struct thread_info *thread_info;
686 atomic_t usage;
687 unsigned long flags; /* per process flags, defined below */
688 unsigned long ptrace;
689
Paolo 'Blaisorblade' Giarrusso36772092005-05-05 16:16:12 -0700690 int lock_depth; /* BKL lock depth */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700691
Nick Piggin4866cde2005-06-25 14:57:23 -0700692#if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW)
693 int oncpu;
694#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700695 int prio, static_prio;
696 struct list_head run_list;
697 prio_array_t *array;
698
Jens Axboe22e2c502005-06-27 10:55:12 +0200699 unsigned short ioprio;
700
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701 unsigned long sleep_avg;
702 unsigned long long timestamp, last_ran;
703 unsigned long long sched_time; /* sched_clock time spent running */
704 int activated;
705
706 unsigned long policy;
707 cpumask_t cpus_allowed;
708 unsigned int time_slice, first_time_slice;
709
710#ifdef CONFIG_SCHEDSTATS
711 struct sched_info sched_info;
712#endif
713
714 struct list_head tasks;
715 /*
716 * ptrace_list/ptrace_children forms the list of my children
717 * that were stolen by a ptracer.
718 */
719 struct list_head ptrace_children;
720 struct list_head ptrace_list;
721
722 struct mm_struct *mm, *active_mm;
723
724/* task state */
725 struct linux_binfmt *binfmt;
726 long exit_state;
727 int exit_code, exit_signal;
728 int pdeath_signal; /* The signal sent when the parent dies */
729 /* ??? */
730 unsigned long personality;
731 unsigned did_exec:1;
732 pid_t pid;
733 pid_t tgid;
734 /*
735 * pointers to (original) parent process, youngest child, younger sibling,
736 * older sibling, respectively. (p->father can be replaced with
737 * p->parent->pid)
738 */
739 struct task_struct *real_parent; /* real parent process (when being debugged) */
740 struct task_struct *parent; /* parent process */
741 /*
742 * children/sibling forms the list of my children plus the
743 * tasks I'm ptracing.
744 */
745 struct list_head children; /* list of my children */
746 struct list_head sibling; /* linkage in my parent's children list */
747 struct task_struct *group_leader; /* threadgroup leader */
748
749 /* PID/PID hash table linkage. */
750 struct pid pids[PIDTYPE_MAX];
751
752 struct completion *vfork_done; /* for vfork() */
753 int __user *set_child_tid; /* CLONE_CHILD_SETTID */
754 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
755
756 unsigned long rt_priority;
757 cputime_t utime, stime;
758 unsigned long nvcsw, nivcsw; /* context switch counts */
759 struct timespec start_time;
760/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
761 unsigned long min_flt, maj_flt;
762
763 cputime_t it_prof_expires, it_virt_expires;
764 unsigned long long it_sched_expires;
765 struct list_head cpu_timers[3];
766
767/* process credentials */
768 uid_t uid,euid,suid,fsuid;
769 gid_t gid,egid,sgid,fsgid;
770 struct group_info *group_info;
771 kernel_cap_t cap_effective, cap_inheritable, cap_permitted;
772 unsigned keep_capabilities:1;
773 struct user_struct *user;
774#ifdef CONFIG_KEYS
David Howellsb5f545c2006-01-08 01:02:47 -0800775 struct key *request_key_auth; /* assumed request_key authority */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776 struct key *thread_keyring; /* keyring private to this thread */
David Howells3e301482005-06-23 22:00:56 -0700777 unsigned char jit_keyring; /* default keyring to attach requested keys to */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778#endif
779 int oomkilladj; /* OOM kill score adjustment (bit shift). */
Paolo 'Blaisorblade' Giarrusso36772092005-05-05 16:16:12 -0700780 char comm[TASK_COMM_LEN]; /* executable name excluding path
781 - access with [gs]et_task_comm (which lock
782 it with task_lock())
783 - initialized normally by flush_old_exec */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784/* file system info */
785 int link_count, total_link_count;
786/* ipc stuff */
787 struct sysv_sem sysvsem;
788/* CPU-specific state of this task */
789 struct thread_struct thread;
790/* filesystem information */
791 struct fs_struct *fs;
792/* open file information */
793 struct files_struct *files;
794/* namespace */
795 struct namespace *namespace;
796/* signal handlers */
797 struct signal_struct *signal;
798 struct sighand_struct *sighand;
799
800 sigset_t blocked, real_blocked;
801 struct sigpending pending;
802
803 unsigned long sas_ss_sp;
804 size_t sas_ss_size;
805 int (*notifier)(void *priv);
806 void *notifier_data;
807 sigset_t *notifier_mask;
808
809 void *security;
810 struct audit_context *audit_context;
811 seccomp_t seccomp;
812
813/* Thread group tracking */
814 u32 parent_exec_id;
815 u32 self_exec_id;
816/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
817 spinlock_t alloc_lock;
818/* Protection of proc_dentry: nesting proc_lock, dcache_lock, write_lock_irq(&tasklist_lock); */
819 spinlock_t proc_lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820
Ingo Molnar408894e2006-01-09 15:59:20 -0800821#ifdef CONFIG_DEBUG_MUTEXES
822 /* mutex deadlock detection */
823 struct mutex_waiter *blocked_on;
824#endif
825
Linus Torvalds1da177e2005-04-16 15:20:36 -0700826/* journalling filesystem info */
827 void *journal_info;
828
829/* VM state */
830 struct reclaim_state *reclaim_state;
831
832 struct dentry *proc_dentry;
833 struct backing_dev_info *backing_dev_info;
834
835 struct io_context *io_context;
836
837 unsigned long ptrace_message;
838 siginfo_t *last_siginfo; /* For ptrace use. */
839/*
840 * current io wait handle: wait queue entry to use for io waits
841 * If this thread is processing aio, this points at the waitqueue
842 * inside the currently handled kiocb. It may be NULL (i.e. default
843 * to a stack based synchronous wait) if its doing sync IO.
844 */
845 wait_queue_t *io_wait;
846/* i/o counters(bytes read/written, #syscalls */
847 u64 rchar, wchar, syscr, syscw;
848#if defined(CONFIG_BSD_PROCESS_ACCT)
849 u64 acct_rss_mem1; /* accumulated rss usage */
850 u64 acct_vm_mem1; /* accumulated virtual memory usage */
851 clock_t acct_stimexpd; /* clock_t-converted stime since last update */
852#endif
853#ifdef CONFIG_NUMA
854 struct mempolicy *mempolicy;
855 short il_next;
856#endif
857#ifdef CONFIG_CPUSETS
858 struct cpuset *cpuset;
859 nodemask_t mems_allowed;
860 int cpuset_mems_generation;
861#endif
Jens Axboe22e2c502005-06-27 10:55:12 +0200862 atomic_t fs_excl; /* holding fs exclusive resources */
Ingo Molnare56d0902006-01-08 01:01:37 -0800863 struct rcu_head rcu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700864};
865
866static inline pid_t process_group(struct task_struct *tsk)
867{
868 return tsk->signal->pgrp;
869}
870
871/**
872 * pid_alive - check that a task structure is not stale
873 * @p: Task structure to be checked.
874 *
875 * Test if a process is not yet dead (at most zombie state)
876 * If pid_alive fails, then pointers within the task structure
877 * can be stale and must not be dereferenced.
878 */
879static inline int pid_alive(struct task_struct *p)
880{
881 return p->pids[PIDTYPE_PID].nr != 0;
882}
883
884extern void free_task(struct task_struct *tsk);
885extern void __put_task_struct(struct task_struct *tsk);
886#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
Ingo Molnare56d0902006-01-08 01:01:37 -0800887
Ingo Molnare56d0902006-01-08 01:01:37 -0800888extern void __put_task_struct_cb(struct rcu_head *rhp);
889
890static inline void put_task_struct(struct task_struct *t)
891{
892 if (atomic_dec_and_test(&t->usage))
893 call_rcu(&t->rcu, __put_task_struct_cb);
894}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895
896/*
897 * Per process flags
898 */
899#define PF_ALIGNWARN 0x00000001 /* Print alignment warning msgs */
900 /* Not implemented yet, only for 486*/
901#define PF_STARTING 0x00000002 /* being created */
902#define PF_EXITING 0x00000004 /* getting shut down */
903#define PF_DEAD 0x00000008 /* Dead */
904#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
905#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
906#define PF_DUMPCORE 0x00000200 /* dumped core */
907#define PF_SIGNALED 0x00000400 /* killed by a signal */
908#define PF_MEMALLOC 0x00000800 /* Allocating memory */
909#define PF_FLUSHER 0x00001000 /* responsible for disk writeback */
910#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
911#define PF_FREEZE 0x00004000 /* this task is being frozen for suspend now */
912#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
913#define PF_FROZEN 0x00010000 /* frozen for system suspend */
914#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
915#define PF_KSWAPD 0x00040000 /* I am kswapd */
916#define PF_SWAPOFF 0x00080000 /* I am in swapoff */
917#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
918#define PF_SYNCWRITE 0x00200000 /* I am doing a sync write */
919#define PF_BORROWED_MM 0x00400000 /* I am a kthread doing use_mm */
920#define PF_RANDOMIZE 0x00800000 /* randomize virtual address space */
Christoph Lameter930d9152006-01-08 01:00:47 -0800921#define PF_SWAPWRITE 0x01000000 /* Allowed to write to swap */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700922
923/*
924 * Only the _current_ task can read/write to tsk->flags, but other
925 * tasks can access tsk->flags in readonly mode for example
926 * with tsk_used_math (like during threaded core dumping).
927 * There is however an exception to this rule during ptrace
928 * or during fork: the ptracer task is allowed to write to the
929 * child->flags of its traced child (same goes for fork, the parent
930 * can write to the child->flags), because we're guaranteed the
931 * child is not running and in turn not changing child->flags
932 * at the same time the parent does it.
933 */
934#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
935#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
936#define clear_used_math() clear_stopped_child_used_math(current)
937#define set_used_math() set_stopped_child_used_math(current)
938#define conditional_stopped_child_used_math(condition, child) \
939 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
940#define conditional_used_math(condition) \
941 conditional_stopped_child_used_math(condition, current)
942#define copy_to_stopped_child_used_math(child) \
943 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
944/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
945#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
946#define used_math() tsk_used_math(current)
947
948#ifdef CONFIG_SMP
949extern int set_cpus_allowed(task_t *p, cpumask_t new_mask);
950#else
951static inline int set_cpus_allowed(task_t *p, cpumask_t new_mask)
952{
Paul Jackson4098f992005-10-30 15:03:21 -0800953 if (!cpu_isset(0, new_mask))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700954 return -EINVAL;
955 return 0;
956}
957#endif
958
959extern unsigned long long sched_clock(void);
960extern unsigned long long current_sched_time(const task_t *current_task);
961
962/* sched_exec is called by processes performing an exec */
963#ifdef CONFIG_SMP
964extern void sched_exec(void);
965#else
966#define sched_exec() {}
967#endif
968
969#ifdef CONFIG_HOTPLUG_CPU
970extern void idle_task_exit(void);
971#else
972static inline void idle_task_exit(void) {}
973#endif
974
975extern void sched_idle_next(void);
976extern void set_user_nice(task_t *p, long nice);
977extern int task_prio(const task_t *p);
978extern int task_nice(const task_t *p);
Matt Mackalle43379f2005-05-01 08:59:00 -0700979extern int can_nice(const task_t *p, const int nice);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700980extern int task_curr(const task_t *p);
981extern int idle_cpu(int cpu);
982extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
983extern task_t *idle_task(int cpu);
Keith Owensa2a97982005-09-11 17:19:06 +1000984extern task_t *curr_task(int cpu);
985extern void set_curr_task(int cpu, task_t *p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700986
987void yield(void);
988
989/*
990 * The default (Linux) execution domain.
991 */
992extern struct exec_domain default_exec_domain;
993
994union thread_union {
995 struct thread_info thread_info;
996 unsigned long stack[THREAD_SIZE/sizeof(long)];
997};
998
999#ifndef __HAVE_ARCH_KSTACK_END
1000static inline int kstack_end(void *addr)
1001{
1002 /* Reliable end of stack detection:
1003 * Some APM bios versions misalign the stack
1004 */
1005 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1006}
1007#endif
1008
1009extern union thread_union init_thread_union;
1010extern struct task_struct init_task;
1011
1012extern struct mm_struct init_mm;
1013
1014#define find_task_by_pid(nr) find_task_by_pid_type(PIDTYPE_PID, nr)
1015extern struct task_struct *find_task_by_pid_type(int type, int pid);
1016extern void set_special_pids(pid_t session, pid_t pgrp);
1017extern void __set_special_pids(pid_t session, pid_t pgrp);
1018
1019/* per-UID process charging. */
1020extern struct user_struct * alloc_uid(uid_t);
1021static inline struct user_struct *get_uid(struct user_struct *u)
1022{
1023 atomic_inc(&u->__count);
1024 return u;
1025}
1026extern void free_uid(struct user_struct *);
1027extern void switch_uid(struct user_struct *);
1028
1029#include <asm/current.h>
1030
1031extern void do_timer(struct pt_regs *);
1032
1033extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state));
1034extern int FASTCALL(wake_up_process(struct task_struct * tsk));
1035extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
1036 unsigned long clone_flags));
1037#ifdef CONFIG_SMP
1038 extern void kick_process(struct task_struct *tsk);
1039#else
1040 static inline void kick_process(struct task_struct *tsk) { }
1041#endif
Nick Piggin476d1392005-06-25 14:57:29 -07001042extern void FASTCALL(sched_fork(task_t * p, int clone_flags));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001043extern void FASTCALL(sched_exit(task_t * p));
1044
1045extern int in_group_p(gid_t);
1046extern int in_egroup_p(gid_t);
1047
1048extern void proc_caches_init(void);
1049extern void flush_signals(struct task_struct *);
1050extern void flush_signal_handlers(struct task_struct *, int force_default);
1051extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1052
1053static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1054{
1055 unsigned long flags;
1056 int ret;
1057
1058 spin_lock_irqsave(&tsk->sighand->siglock, flags);
1059 ret = dequeue_signal(tsk, mask, info);
1060 spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1061
1062 return ret;
1063}
1064
1065extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1066 sigset_t *mask);
1067extern void unblock_all_signals(void);
1068extern void release_task(struct task_struct * p);
1069extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1070extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
1071extern int force_sigsegv(int, struct task_struct *);
1072extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1073extern int __kill_pg_info(int sig, struct siginfo *info, pid_t pgrp);
1074extern int kill_pg_info(int, struct siginfo *, pid_t);
1075extern int kill_proc_info(int, struct siginfo *, pid_t);
Harald Welte46113832005-10-10 19:44:29 +02001076extern int kill_proc_info_as_uid(int, struct siginfo *, pid_t, uid_t, uid_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001077extern void do_notify_parent(struct task_struct *, int);
1078extern void force_sig(int, struct task_struct *);
1079extern void force_sig_specific(int, struct task_struct *);
1080extern int send_sig(int, struct task_struct *, int);
1081extern void zap_other_threads(struct task_struct *p);
1082extern int kill_pg(pid_t, int, int);
1083extern int kill_sl(pid_t, int, int);
1084extern int kill_proc(pid_t, int, int);
1085extern struct sigqueue *sigqueue_alloc(void);
1086extern void sigqueue_free(struct sigqueue *);
1087extern int send_sigqueue(int, struct sigqueue *, struct task_struct *);
1088extern int send_group_sigqueue(int, struct sigqueue *, struct task_struct *);
1089extern int do_sigaction(int, const struct k_sigaction *, struct k_sigaction *);
1090extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1091
1092/* These can be the second arg to send_sig_info/send_group_sig_info. */
1093#define SEND_SIG_NOINFO ((struct siginfo *) 0)
1094#define SEND_SIG_PRIV ((struct siginfo *) 1)
1095#define SEND_SIG_FORCED ((struct siginfo *) 2)
1096
Oleg Nesterov621d3122005-10-30 15:03:45 -08001097static inline int is_si_special(const struct siginfo *info)
1098{
1099 return info <= SEND_SIG_FORCED;
1100}
1101
Linus Torvalds1da177e2005-04-16 15:20:36 -07001102/* True if we are on the alternate signal stack. */
1103
1104static inline int on_sig_stack(unsigned long sp)
1105{
1106 return (sp - current->sas_ss_sp < current->sas_ss_size);
1107}
1108
1109static inline int sas_ss_flags(unsigned long sp)
1110{
1111 return (current->sas_ss_size == 0 ? SS_DISABLE
1112 : on_sig_stack(sp) ? SS_ONSTACK : 0);
1113}
1114
Linus Torvalds1da177e2005-04-16 15:20:36 -07001115/*
1116 * Routines for handling mm_structs
1117 */
1118extern struct mm_struct * mm_alloc(void);
1119
1120/* mmdrop drops the mm and the page tables */
1121extern void FASTCALL(__mmdrop(struct mm_struct *));
1122static inline void mmdrop(struct mm_struct * mm)
1123{
1124 if (atomic_dec_and_test(&mm->mm_count))
1125 __mmdrop(mm);
1126}
1127
1128/* mmput gets rid of the mappings and all user-space */
1129extern void mmput(struct mm_struct *);
1130/* Grab a reference to a task's mm, if it is not already going away */
1131extern struct mm_struct *get_task_mm(struct task_struct *task);
1132/* Remove the current tasks stale references to the old mm_struct */
1133extern void mm_release(struct task_struct *, struct mm_struct *);
1134
1135extern int copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1136extern void flush_thread(void);
1137extern void exit_thread(void);
1138
Linus Torvalds1da177e2005-04-16 15:20:36 -07001139extern void exit_files(struct task_struct *);
1140extern void exit_signal(struct task_struct *);
1141extern void __exit_signal(struct task_struct *);
1142extern void exit_sighand(struct task_struct *);
1143extern void __exit_sighand(struct task_struct *);
1144extern void exit_itimers(struct signal_struct *);
1145
1146extern NORET_TYPE void do_group_exit(int);
1147
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148extern void daemonize(const char *, ...);
1149extern int allow_signal(int);
1150extern int disallow_signal(int);
1151extern task_t *child_reaper;
1152
1153extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1154extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1155task_t *fork_idle(int);
1156
1157extern void set_task_comm(struct task_struct *tsk, char *from);
1158extern void get_task_comm(char *to, struct task_struct *tsk);
1159
1160#ifdef CONFIG_SMP
1161extern void wait_task_inactive(task_t * p);
1162#else
1163#define wait_task_inactive(p) do { } while (0)
1164#endif
1165
1166#define remove_parent(p) list_del_init(&(p)->sibling)
1167#define add_parent(p, parent) list_add_tail(&(p)->sibling,&(parent)->children)
1168
1169#define REMOVE_LINKS(p) do { \
1170 if (thread_group_leader(p)) \
1171 list_del_init(&(p)->tasks); \
1172 remove_parent(p); \
1173 } while (0)
1174
1175#define SET_LINKS(p) do { \
1176 if (thread_group_leader(p)) \
1177 list_add_tail(&(p)->tasks,&init_task.tasks); \
1178 add_parent(p, (p)->parent); \
1179 } while (0)
1180
1181#define next_task(p) list_entry((p)->tasks.next, struct task_struct, tasks)
1182#define prev_task(p) list_entry((p)->tasks.prev, struct task_struct, tasks)
1183
1184#define for_each_process(p) \
1185 for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1186
1187/*
1188 * Careful: do_each_thread/while_each_thread is a double loop so
1189 * 'break' will not work as expected - use goto instead.
1190 */
1191#define do_each_thread(g, t) \
1192 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1193
1194#define while_each_thread(g, t) \
1195 while ((t = next_thread(t)) != g)
1196
1197extern task_t * FASTCALL(next_thread(const task_t *p));
1198
1199#define thread_group_leader(p) (p->pid == p->tgid)
1200
1201static inline int thread_group_empty(task_t *p)
1202{
1203 return list_empty(&p->pids[PIDTYPE_TGID].pid_list);
1204}
1205
1206#define delay_group_leader(p) \
1207 (thread_group_leader(p) && !thread_group_empty(p))
1208
1209extern void unhash_process(struct task_struct *p);
1210
1211/*
1212 * Protects ->fs, ->files, ->mm, ->ptrace, ->group_info, ->comm, keyring
Jens Axboe22e2c502005-06-27 10:55:12 +02001213 * subscriptions and synchronises with wait4(). Also used in procfs. Also
Paul Jackson053199e2005-10-30 15:02:30 -08001214 * pins the final release of task.io_context. Also protects ->cpuset.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001215 *
1216 * Nests both inside and outside of read_lock(&tasklist_lock).
1217 * It must not be nested with write_lock_irq(&tasklist_lock),
1218 * neither inside nor outside.
1219 */
1220static inline void task_lock(struct task_struct *p)
1221{
1222 spin_lock(&p->alloc_lock);
1223}
1224
1225static inline void task_unlock(struct task_struct *p)
1226{
1227 spin_unlock(&p->alloc_lock);
1228}
1229
Al Virof0373602005-11-13 16:06:57 -08001230#ifndef __HAVE_THREAD_FUNCTIONS
1231
Al Viroa1261f52005-11-13 16:06:55 -08001232#define task_thread_info(task) (task)->thread_info
1233
Al Viro10ebffd2005-11-13 16:06:56 -08001234static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
1235{
1236 *task_thread_info(p) = *task_thread_info(org);
1237 task_thread_info(p)->task = p;
1238}
1239
1240static inline unsigned long *end_of_stack(struct task_struct *p)
1241{
1242 return (unsigned long *)(p->thread_info + 1);
1243}
1244
Al Virof0373602005-11-13 16:06:57 -08001245#endif
1246
Linus Torvalds1da177e2005-04-16 15:20:36 -07001247/* set thread flags in other task's structures
1248 * - see asm/thread_info.h for TIF_xxxx flags available
1249 */
1250static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1251{
Al Viroa1261f52005-11-13 16:06:55 -08001252 set_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001253}
1254
1255static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1256{
Al Viroa1261f52005-11-13 16:06:55 -08001257 clear_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001258}
1259
1260static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1261{
Al Viroa1261f52005-11-13 16:06:55 -08001262 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001263}
1264
1265static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1266{
Al Viroa1261f52005-11-13 16:06:55 -08001267 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001268}
1269
1270static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1271{
Al Viroa1261f52005-11-13 16:06:55 -08001272 return test_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001273}
1274
1275static inline void set_tsk_need_resched(struct task_struct *tsk)
1276{
1277 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1278}
1279
1280static inline void clear_tsk_need_resched(struct task_struct *tsk)
1281{
1282 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1283}
1284
1285static inline int signal_pending(struct task_struct *p)
1286{
1287 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1288}
1289
1290static inline int need_resched(void)
1291{
1292 return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1293}
1294
1295/*
1296 * cond_resched() and cond_resched_lock(): latency reduction via
1297 * explicit rescheduling in places that are safe. The return
1298 * value indicates whether a reschedule was done in fact.
1299 * cond_resched_lock() will drop the spinlock before scheduling,
1300 * cond_resched_softirq() will enable bhs before scheduling.
1301 */
1302extern int cond_resched(void);
1303extern int cond_resched_lock(spinlock_t * lock);
1304extern int cond_resched_softirq(void);
1305
1306/*
1307 * Does a critical section need to be broken due to another
1308 * task waiting?:
1309 */
1310#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
1311# define need_lockbreak(lock) ((lock)->break_lock)
1312#else
1313# define need_lockbreak(lock) 0
1314#endif
1315
1316/*
1317 * Does a critical section need to be broken due to another
1318 * task waiting or preemption being signalled:
1319 */
1320static inline int lock_need_resched(spinlock_t *lock)
1321{
1322 if (need_lockbreak(lock) || need_resched())
1323 return 1;
1324 return 0;
1325}
1326
1327/* Reevaluate whether the task has signals pending delivery.
1328 This is required every time the blocked sigset_t changes.
1329 callers must hold sighand->siglock. */
1330
1331extern FASTCALL(void recalc_sigpending_tsk(struct task_struct *t));
1332extern void recalc_sigpending(void);
1333
1334extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1335
1336/*
1337 * Wrappers for p->thread_info->cpu access. No-op on UP.
1338 */
1339#ifdef CONFIG_SMP
1340
1341static inline unsigned int task_cpu(const struct task_struct *p)
1342{
Al Viroa1261f52005-11-13 16:06:55 -08001343 return task_thread_info(p)->cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001344}
1345
1346static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1347{
Al Viroa1261f52005-11-13 16:06:55 -08001348 task_thread_info(p)->cpu = cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001349}
1350
1351#else
1352
1353static inline unsigned int task_cpu(const struct task_struct *p)
1354{
1355 return 0;
1356}
1357
1358static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1359{
1360}
1361
1362#endif /* CONFIG_SMP */
1363
1364#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1365extern void arch_pick_mmap_layout(struct mm_struct *mm);
1366#else
1367static inline void arch_pick_mmap_layout(struct mm_struct *mm)
1368{
1369 mm->mmap_base = TASK_UNMAPPED_BASE;
1370 mm->get_unmapped_area = arch_get_unmapped_area;
1371 mm->unmap_area = arch_unmap_area;
1372}
1373#endif
1374
1375extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
1376extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
1377
Linus Torvalds1da177e2005-04-16 15:20:36 -07001378extern void normalize_rt_tasks(void);
1379
Linus Torvalds1da177e2005-04-16 15:20:36 -07001380#ifdef CONFIG_PM
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001381/*
1382 * Check if a process has been frozen
1383 */
1384static inline int frozen(struct task_struct *p)
1385{
1386 return p->flags & PF_FROZEN;
1387}
1388
1389/*
1390 * Check if there is a request to freeze a process
1391 */
1392static inline int freezing(struct task_struct *p)
1393{
1394 return p->flags & PF_FREEZE;
1395}
1396
1397/*
1398 * Request that a process be frozen
1399 * FIXME: SMP problem. We may not modify other process' flags!
1400 */
1401static inline void freeze(struct task_struct *p)
1402{
1403 p->flags |= PF_FREEZE;
1404}
1405
1406/*
1407 * Wake up a frozen process
1408 */
1409static inline int thaw_process(struct task_struct *p)
1410{
1411 if (frozen(p)) {
1412 p->flags &= ~PF_FROZEN;
1413 wake_up_process(p);
1414 return 1;
1415 }
1416 return 0;
1417}
1418
1419/*
1420 * freezing is complete, mark process as frozen
1421 */
1422static inline void frozen_process(struct task_struct *p)
1423{
1424 p->flags = (p->flags & ~PF_FREEZE) | PF_FROZEN;
1425}
1426
1427extern void refrigerator(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001428extern int freeze_processes(void);
1429extern void thaw_processes(void);
1430
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001431static inline int try_to_freeze(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001432{
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001433 if (freezing(current)) {
1434 refrigerator();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001435 return 1;
1436 } else
1437 return 0;
1438}
1439#else
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001440static inline int frozen(struct task_struct *p) { return 0; }
1441static inline int freezing(struct task_struct *p) { return 0; }
1442static inline void freeze(struct task_struct *p) { BUG(); }
1443static inline int thaw_process(struct task_struct *p) { return 1; }
1444static inline void frozen_process(struct task_struct *p) { BUG(); }
1445
1446static inline void refrigerator(void) {}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001447static inline int freeze_processes(void) { BUG(); return 0; }
1448static inline void thaw_processes(void) {}
1449
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001450static inline int try_to_freeze(void) { return 0; }
1451
Linus Torvalds1da177e2005-04-16 15:20:36 -07001452#endif /* CONFIG_PM */
1453#endif /* __KERNEL__ */
1454
1455#endif