blob: dd6c2164e4a4238dd99debc27706b481513b3ea1 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef _LINUX_SCHED_H
2#define _LINUX_SCHED_H
3
David Woodhouseb7b3c762006-04-27 00:12:56 +01004#include <linux/auxvec.h> /* For AT_VECTOR_SIZE */
5
6/*
7 * cloning flags:
8 */
9#define CSIGNAL 0x000000ff /* signal mask to be sent at exit */
10#define CLONE_VM 0x00000100 /* set if VM shared between processes */
11#define CLONE_FS 0x00000200 /* set if fs info shared between processes */
12#define CLONE_FILES 0x00000400 /* set if open files shared between processes */
13#define CLONE_SIGHAND 0x00000800 /* set if signal handlers and blocked signals shared */
14#define CLONE_PTRACE 0x00002000 /* set if we want to let tracing continue on the child too */
15#define CLONE_VFORK 0x00004000 /* set if the parent wants the child to wake it up on mm_release */
16#define CLONE_PARENT 0x00008000 /* set if we want to have the same parent as the cloner */
17#define CLONE_THREAD 0x00010000 /* Same thread group? */
18#define CLONE_NEWNS 0x00020000 /* New namespace group? */
19#define CLONE_SYSVSEM 0x00040000 /* share system V SEM_UNDO semantics */
20#define CLONE_SETTLS 0x00080000 /* create a new TLS for the child */
21#define CLONE_PARENT_SETTID 0x00100000 /* set the TID in the parent */
22#define CLONE_CHILD_CLEARTID 0x00200000 /* clear the TID in the child */
23#define CLONE_DETACHED 0x00400000 /* Unused, ignored */
24#define CLONE_UNTRACED 0x00800000 /* set if the tracing process can't force CLONE_PTRACE on this clone */
25#define CLONE_CHILD_SETTID 0x01000000 /* set the TID in the child */
26#define CLONE_STOPPED 0x02000000 /* Start in stopped state */
27
28/*
29 * Scheduling policies
30 */
31#define SCHED_NORMAL 0
32#define SCHED_FIFO 1
33#define SCHED_RR 2
34#define SCHED_BATCH 3
35
David Woodhousea3b67142006-04-25 14:54:40 +010036#ifdef __KERNEL__
David Woodhouseb7b3c762006-04-27 00:12:56 +010037
38struct sched_param {
39 int sched_priority;
40};
41
Linus Torvalds1da177e2005-04-16 15:20:36 -070042#include <asm/param.h> /* for HZ */
43
Linus Torvalds1da177e2005-04-16 15:20:36 -070044#include <linux/capability.h>
45#include <linux/threads.h>
46#include <linux/kernel.h>
47#include <linux/types.h>
48#include <linux/timex.h>
49#include <linux/jiffies.h>
50#include <linux/rbtree.h>
51#include <linux/thread_info.h>
52#include <linux/cpumask.h>
53#include <linux/errno.h>
54#include <linux/nodemask.h>
55
56#include <asm/system.h>
57#include <asm/semaphore.h>
58#include <asm/page.h>
59#include <asm/ptrace.h>
60#include <asm/mmu.h>
61#include <asm/cputime.h>
62
63#include <linux/smp.h>
64#include <linux/sem.h>
65#include <linux/signal.h>
66#include <linux/securebits.h>
67#include <linux/fs_struct.h>
68#include <linux/compiler.h>
69#include <linux/completion.h>
70#include <linux/pid.h>
71#include <linux/percpu.h>
72#include <linux/topology.h>
73#include <linux/seccomp.h>
Ingo Molnare56d0902006-01-08 01:01:37 -080074#include <linux/rcupdate.h>
Ingo Molnar0771dfe2006-03-27 01:16:22 -080075#include <linux/futex.h>
Ingo Molnar23f78d4a2006-06-27 02:54:53 -070076#include <linux/rtmutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070077
David Woodhousea3b67142006-04-25 14:54:40 +010078#include <linux/time.h>
79#include <linux/param.h>
80#include <linux/resource.h>
81#include <linux/timer.h>
82#include <linux/hrtimer.h>
83
84#include <asm/processor.h>
H. J. Lu36d57ac2005-09-06 15:16:49 -070085
Linus Torvalds1da177e2005-04-16 15:20:36 -070086struct exec_domain;
Ingo Molnarc87e2832006-06-27 02:54:58 -070087struct futex_pi_state;
Linus Torvalds1da177e2005-04-16 15:20:36 -070088
89/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070090 * List of flags we want to share for kernel threads,
91 * if only because they are not used by them anyway.
92 */
93#define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
94
95/*
96 * These are the constant used to fake the fixed-point load-average
97 * counting. Some notes:
98 * - 11 bit fractions expand to 22 bits by the multiplies: this gives
99 * a load-average precision of 10 bits integer + 11 bits fractional
100 * - if you want to count load-averages more often, you need more
101 * precision, or rounding will get you. With 2-second counting freq,
102 * the EXP_n values would be 1981, 2034 and 2043 if still using only
103 * 11 bit fractions.
104 */
105extern unsigned long avenrun[]; /* Load averages */
106
107#define FSHIFT 11 /* nr of bits of precision */
108#define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
109#define LOAD_FREQ (5*HZ) /* 5 sec intervals */
110#define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
111#define EXP_5 2014 /* 1/exp(5sec/5min) */
112#define EXP_15 2037 /* 1/exp(5sec/15min) */
113
114#define CALC_LOAD(load,exp,n) \
115 load *= exp; \
116 load += n*(FIXED_1-exp); \
117 load >>= FSHIFT;
118
119extern unsigned long total_forks;
120extern int nr_threads;
121extern int last_pid;
122DECLARE_PER_CPU(unsigned long, process_counts);
123extern int nr_processes(void);
124extern unsigned long nr_running(void);
125extern unsigned long nr_uninterruptible(void);
Jack Steinerdb1b1fe2006-03-31 02:31:21 -0800126extern unsigned long nr_active(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127extern unsigned long nr_iowait(void);
Peter Williams2dd73a42006-06-27 02:54:34 -0700128extern unsigned long weighted_cpuload(const int cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130
Linus Torvalds4a8342d2005-09-29 15:18:21 -0700131/*
132 * Task state bitmask. NOTE! These bits are also
133 * encoded in fs/proc/array.c: get_task_state().
134 *
135 * We have two separate sets of flags: task->state
136 * is about runnability, while task->exit_state are
137 * about the task exiting. Confusing, but this way
138 * modifying one set can't modify the other one by
139 * mistake.
140 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141#define TASK_RUNNING 0
142#define TASK_INTERRUPTIBLE 1
143#define TASK_UNINTERRUPTIBLE 2
Linus Torvalds4a8342d2005-09-29 15:18:21 -0700144#define TASK_STOPPED 4
145#define TASK_TRACED 8
146/* in tsk->exit_state */
147#define EXIT_ZOMBIE 16
148#define EXIT_DEAD 32
149/* in tsk->state again */
150#define TASK_NONINTERACTIVE 64
Oleg Nesterovc394cc92006-09-29 02:01:11 -0700151#define TASK_DEAD 128
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152
153#define __set_task_state(tsk, state_value) \
154 do { (tsk)->state = (state_value); } while (0)
155#define set_task_state(tsk, state_value) \
156 set_mb((tsk)->state, (state_value))
157
Andrew Morton498d0c52005-09-13 01:25:14 -0700158/*
159 * set_current_state() includes a barrier so that the write of current->state
160 * is correctly serialised wrt the caller's subsequent test of whether to
161 * actually sleep:
162 *
163 * set_current_state(TASK_UNINTERRUPTIBLE);
164 * if (do_i_need_to_sleep())
165 * schedule();
166 *
167 * If the caller does not need such serialisation then use __set_current_state()
168 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169#define __set_current_state(state_value) \
170 do { current->state = (state_value); } while (0)
171#define set_current_state(state_value) \
172 set_mb(current->state, (state_value))
173
174/* Task command name length */
175#define TASK_COMM_LEN 16
176
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177#include <linux/spinlock.h>
178
179/*
180 * This serializes "schedule()" and also protects
181 * the run-queue from deletions/modifications (but
182 * _adding_ to the beginning of the run-queue has
183 * a separate lock).
184 */
185extern rwlock_t tasklist_lock;
186extern spinlock_t mmlist_lock;
187
Ingo Molnar36c8b582006-07-03 00:25:41 -0700188struct task_struct;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189
190extern void sched_init(void);
191extern void sched_init_smp(void);
Ingo Molnar36c8b582006-07-03 00:25:41 -0700192extern void init_idle(struct task_struct *idle, int cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193
194extern cpumask_t nohz_cpu_mask;
195
196extern void show_state(void);
197extern void show_regs(struct pt_regs *);
198
199/*
200 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
201 * task), SP is the stack pointer of the first frame that should be shown in the back
202 * trace (or NULL if the entire call-chain of the task should be shown).
203 */
204extern void show_stack(struct task_struct *task, unsigned long *sp);
205
206void io_schedule(void);
207long io_schedule_timeout(long timeout);
208
209extern void cpu_init (void);
210extern void trap_init(void);
211extern void update_process_times(int user);
212extern void scheduler_tick(void);
213
Ingo Molnar8446f1d2005-09-06 15:16:27 -0700214#ifdef CONFIG_DETECT_SOFTLOCKUP
Ingo Molnar6687a972006-03-24 03:18:41 -0800215extern void softlockup_tick(void);
Ingo Molnar8446f1d2005-09-06 15:16:27 -0700216extern void spawn_softlockup_task(void);
217extern void touch_softlockup_watchdog(void);
218#else
Ingo Molnar6687a972006-03-24 03:18:41 -0800219static inline void softlockup_tick(void)
Ingo Molnar8446f1d2005-09-06 15:16:27 -0700220{
221}
222static inline void spawn_softlockup_task(void)
223{
224}
225static inline void touch_softlockup_watchdog(void)
226{
227}
228#endif
229
230
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231/* Attach to any functions which should be ignored in wchan output. */
232#define __sched __attribute__((__section__(".sched.text")))
233/* Is this address in the __sched functions? */
234extern int in_sched_functions(unsigned long addr);
235
236#define MAX_SCHEDULE_TIMEOUT LONG_MAX
237extern signed long FASTCALL(schedule_timeout(signed long timeout));
Nishanth Aravamudan64ed93a2005-09-10 00:27:21 -0700238extern signed long schedule_timeout_interruptible(signed long timeout);
239extern signed long schedule_timeout_uninterruptible(signed long timeout);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240asmlinkage void schedule(void);
241
242struct namespace;
243
244/* Maximum number of active map areas.. This is a random (large) number */
245#define DEFAULT_MAX_MAP_COUNT 65536
246
247extern int sysctl_max_map_count;
248
249#include <linux/aio.h>
250
251extern unsigned long
252arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
253 unsigned long, unsigned long);
254extern unsigned long
255arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
256 unsigned long len, unsigned long pgoff,
257 unsigned long flags);
Wolfgang Wander1363c3c2005-06-21 17:14:49 -0700258extern void arch_unmap_area(struct mm_struct *, unsigned long);
259extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700261#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
262/*
263 * The mm counters are not protected by its page_table_lock,
264 * so must be incremented atomically.
265 */
Christoph Lameterd3cb4872006-01-06 00:11:20 -0800266#define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
267#define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
268#define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
269#define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
270#define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
271typedef atomic_long_t mm_counter_t;
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700272
273#else /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
274/*
275 * The mm counters are protected by its page_table_lock,
276 * so can be incremented directly.
277 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278#define set_mm_counter(mm, member, value) (mm)->_##member = (value)
279#define get_mm_counter(mm, member) ((mm)->_##member)
280#define add_mm_counter(mm, member, value) (mm)->_##member += (value)
281#define inc_mm_counter(mm, member) (mm)->_##member++
282#define dec_mm_counter(mm, member) (mm)->_##member--
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700283typedef unsigned long mm_counter_t;
Hugh Dickins42946212005-10-29 18:16:05 -0700284
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700285#endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
286
287#define get_mm_rss(mm) \
288 (get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
Hugh Dickins365e9c872005-10-29 18:16:18 -0700289#define update_hiwater_rss(mm) do { \
290 unsigned long _rss = get_mm_rss(mm); \
291 if ((mm)->hiwater_rss < _rss) \
292 (mm)->hiwater_rss = _rss; \
293} while (0)
294#define update_hiwater_vm(mm) do { \
295 if ((mm)->hiwater_vm < (mm)->total_vm) \
296 (mm)->hiwater_vm = (mm)->total_vm; \
297} while (0)
298
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299struct mm_struct {
300 struct vm_area_struct * mmap; /* list of VMAs */
301 struct rb_root mm_rb;
302 struct vm_area_struct * mmap_cache; /* last find_vma result */
303 unsigned long (*get_unmapped_area) (struct file *filp,
304 unsigned long addr, unsigned long len,
305 unsigned long pgoff, unsigned long flags);
Wolfgang Wander1363c3c2005-06-21 17:14:49 -0700306 void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
Benjamin Herrenschmidt0551fbd2006-02-28 16:59:19 -0800307 unsigned long mmap_base; /* base of mmap area */
308 unsigned long task_size; /* size of task vm space */
309 unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */
Wolfgang Wander1363c3c2005-06-21 17:14:49 -0700310 unsigned long free_area_cache; /* first hole of size cached_hole_size or larger */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311 pgd_t * pgd;
312 atomic_t mm_users; /* How many users with user space? */
313 atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */
314 int map_count; /* number of VMAs */
315 struct rw_semaphore mmap_sem;
316 spinlock_t page_table_lock; /* Protects page tables and some counters */
317
318 struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung
319 * together off init_mm.mmlist, and are protected
320 * by mmlist_lock
321 */
322
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700323 /* Special counters, in some configurations protected by the
324 * page_table_lock, in other configurations by being atomic.
325 */
Hugh Dickins42946212005-10-29 18:16:05 -0700326 mm_counter_t _file_rss;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700327 mm_counter_t _anon_rss;
328
Hugh Dickinsf4499522005-10-29 18:16:19 -0700329 unsigned long hiwater_rss; /* High-watermark of RSS usage */
330 unsigned long hiwater_vm; /* High-water virtual memory usage */
331
332 unsigned long total_vm, locked_vm, shared_vm, exec_vm;
333 unsigned long stack_vm, reserved_vm, def_flags, nr_ptes;
334 unsigned long start_code, end_code, start_data, end_data;
335 unsigned long start_brk, brk, start_stack;
336 unsigned long arg_start, arg_end, env_start, env_end;
337
H. J. Lu36d57ac2005-09-06 15:16:49 -0700338 unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339
Alan Coxd6e71142005-06-23 00:09:43 -0700340 unsigned dumpable:2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341 cpumask_t cpu_vm_mask;
342
343 /* Architecture-specific MM context */
344 mm_context_t context;
345
346 /* Token based thrashing protection. */
347 unsigned long swap_token_time;
348 char recent_pagein;
349
350 /* coredumping support */
351 int core_waiters;
352 struct completion *core_startup_done, core_done;
353
354 /* aio bits */
355 rwlock_t ioctx_list_lock;
356 struct kioctx *ioctx_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357};
358
359struct sighand_struct {
360 atomic_t count;
361 struct k_sigaction action[_NSIG];
362 spinlock_t siglock;
363};
364
KaiGai Kohei0e464812006-06-25 05:49:24 -0700365struct pacct_struct {
KaiGai Koheif6ec29a2006-06-25 05:49:25 -0700366 int ac_flag;
367 long ac_exitcode;
KaiGai Kohei0e464812006-06-25 05:49:24 -0700368 unsigned long ac_mem;
KaiGai Kohei77787bf2006-06-25 05:49:26 -0700369 cputime_t ac_utime, ac_stime;
370 unsigned long ac_minflt, ac_majflt;
KaiGai Kohei0e464812006-06-25 05:49:24 -0700371};
372
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373/*
374 * NOTE! "signal_struct" does not have it's own
375 * locking, because a shared signal_struct always
376 * implies a shared sighand_struct, so locking
377 * sighand_struct is always a proper superset of
378 * the locking of signal_struct.
379 */
380struct signal_struct {
381 atomic_t count;
382 atomic_t live;
383
384 wait_queue_head_t wait_chldexit; /* for wait4() */
385
386 /* current thread group signal load-balancing target: */
Ingo Molnar36c8b582006-07-03 00:25:41 -0700387 struct task_struct *curr_target;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388
389 /* shared signal handling: */
390 struct sigpending shared_pending;
391
392 /* thread group exit support */
393 int group_exit_code;
394 /* overloaded:
395 * - notify group_exit_task when ->count is equal to notify_count
396 * - everyone except group_exit_task is stopped during signal delivery
397 * of fatal signals, group_exit_task processes the signal.
398 */
399 struct task_struct *group_exit_task;
400 int notify_count;
401
402 /* thread group stop support, overloads group_exit_code too */
403 int group_stop_count;
404 unsigned int flags; /* see SIGNAL_* flags below */
405
406 /* POSIX.1b Interval Timers */
407 struct list_head posix_timers;
408
409 /* ITIMER_REAL timer for the process */
Thomas Gleixner2ff678b2006-01-09 20:52:34 -0800410 struct hrtimer real_timer;
Roman Zippel05cfb612006-03-26 01:38:12 -0800411 struct task_struct *tsk;
Thomas Gleixner2ff678b2006-01-09 20:52:34 -0800412 ktime_t it_real_incr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413
414 /* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
415 cputime_t it_prof_expires, it_virt_expires;
416 cputime_t it_prof_incr, it_virt_incr;
417
418 /* job control IDs */
419 pid_t pgrp;
420 pid_t tty_old_pgrp;
421 pid_t session;
422 /* boolean value for session group leader */
423 int leader;
424
425 struct tty_struct *tty; /* NULL if no tty */
426
427 /*
428 * Cumulative resource counters for dead threads in the group,
429 * and for reaped dead child processes forked by this group.
430 * Live threads maintain their own counters and add to these
431 * in __exit_signal, except for the group leader.
432 */
433 cputime_t utime, stime, cutime, cstime;
434 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
435 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
436
437 /*
438 * Cumulative ns of scheduled CPU time for dead threads in the
439 * group, not including a zombie group leader. (This only differs
440 * from jiffies_to_ns(utime + stime) if sched_clock uses something
441 * other than jiffies.)
442 */
443 unsigned long long sched_time;
444
445 /*
446 * We don't bother to synchronize most readers of this at all,
447 * because there is no reader checking a limit that actually needs
448 * to get both rlim_cur and rlim_max atomically, and either one
449 * alone is a single word that can safely be read normally.
450 * getrlimit/setrlimit use task_lock(current->group_leader) to
451 * protect this instead of the siglock, because they really
452 * have no need to disable irqs.
453 */
454 struct rlimit rlim[RLIM_NLIMITS];
455
456 struct list_head cpu_timers[3];
457
458 /* keep the process-shared keyrings here so that they do the right
459 * thing in threads created with CLONE_THREAD */
460#ifdef CONFIG_KEYS
461 struct key *session_keyring; /* keyring inherited over fork */
462 struct key *process_keyring; /* keyring private to this process */
463#endif
KaiGai Kohei0e464812006-06-25 05:49:24 -0700464#ifdef CONFIG_BSD_PROCESS_ACCT
465 struct pacct_struct pacct; /* per-process accounting information */
466#endif
Shailabh Nagarad4ecbc2006-07-14 00:24:44 -0700467#ifdef CONFIG_TASKSTATS
468 spinlock_t stats_lock;
469 struct taskstats *stats;
470#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700471};
472
Nick Piggin4866cde2005-06-25 14:57:23 -0700473/* Context switch must be unlocked if interrupts are to be enabled */
474#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
475# define __ARCH_WANT_UNLOCKED_CTXSW
476#endif
477
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478/*
479 * Bits in flags field of signal_struct.
480 */
481#define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */
482#define SIGNAL_STOP_DEQUEUED 0x00000002 /* stop signal dequeued */
483#define SIGNAL_STOP_CONTINUED 0x00000004 /* SIGCONT since WCONTINUED reap */
484#define SIGNAL_GROUP_EXIT 0x00000008 /* group exit in progress */
485
486
487/*
488 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
Ingo Molnarb0a94992006-01-14 13:20:41 -0800489 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
490 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
491 * values are inverted: lower p->prio value means higher priority.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492 *
493 * The MAX_USER_RT_PRIO value allows the actual maximum
494 * RT priority to be separate from the value exported to
495 * user-space. This allows kernel threads to set their
496 * priority to a value higher than any user task. Note:
497 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
498 */
499
500#define MAX_USER_RT_PRIO 100
501#define MAX_RT_PRIO MAX_USER_RT_PRIO
502
503#define MAX_PRIO (MAX_RT_PRIO + 40)
504
Ingo Molnarb29739f2006-06-27 02:54:51 -0700505#define rt_prio(prio) unlikely((prio) < MAX_RT_PRIO)
506#define rt_task(p) rt_prio((p)->prio)
Con Kolivasd425b272006-03-31 02:31:29 -0800507#define batch_task(p) (unlikely((p)->policy == SCHED_BATCH))
Oleg Nesterov57a6f51c2006-09-29 02:00:49 -0700508#define is_rt_policy(p) ((p) != SCHED_NORMAL && (p) != SCHED_BATCH)
509#define has_rt_policy(p) unlikely(is_rt_policy((p)->policy))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510
511/*
512 * Some day this will be a full-fledged user tracking system..
513 */
514struct user_struct {
515 atomic_t __count; /* reference count */
516 atomic_t processes; /* How many processes does this user have? */
517 atomic_t files; /* How many open files does this user have? */
518 atomic_t sigpending; /* How many pending signals does this user have? */
Amy Griffis2d9048e2006-06-01 13:10:59 -0700519#ifdef CONFIG_INOTIFY_USER
Robert Love0eeca282005-07-12 17:06:03 -0400520 atomic_t inotify_watches; /* How many inotify watches does this user have? */
521 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */
522#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523 /* protected by mq_lock */
524 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
525 unsigned long locked_shm; /* How many pages of mlocked shm ? */
526
527#ifdef CONFIG_KEYS
528 struct key *uid_keyring; /* UID specific keyring */
529 struct key *session_keyring; /* UID's default session keyring */
530#endif
531
532 /* Hash table maintenance information */
533 struct list_head uidhash_list;
534 uid_t uid;
535};
536
537extern struct user_struct *find_user(uid_t);
538
539extern struct user_struct root_user;
540#define INIT_USER (&root_user)
541
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542struct backing_dev_info;
543struct reclaim_state;
544
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700545#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546struct sched_info {
547 /* cumulative counters */
548 unsigned long cpu_time, /* time spent on the cpu */
549 run_delay, /* time spent waiting on a runqueue */
550 pcnt; /* # of timeslices run on this cpu */
551
552 /* timestamps */
553 unsigned long last_arrival, /* when we last ran on a cpu */
554 last_queued; /* when we were last queued to run */
555};
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700556#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700558#ifdef CONFIG_SCHEDSTATS
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559extern struct file_operations proc_schedstat_operations;
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700560#endif /* CONFIG_SCHEDSTATS */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700561
Shailabh Nagarca74e922006-07-14 00:24:36 -0700562#ifdef CONFIG_TASK_DELAY_ACCT
563struct task_delay_info {
564 spinlock_t lock;
565 unsigned int flags; /* Private per-task flags */
566
567 /* For each stat XXX, add following, aligned appropriately
568 *
569 * struct timespec XXX_start, XXX_end;
570 * u64 XXX_delay;
571 * u32 XXX_count;
572 *
573 * Atomicity of updates to XXX_delay, XXX_count protected by
574 * single lock above (split into XXX_lock if contention is an issue).
575 */
Shailabh Nagar0ff92242006-07-14 00:24:37 -0700576
577 /*
578 * XXX_count is incremented on every XXX operation, the delay
579 * associated with the operation is added to XXX_delay.
580 * XXX_delay contains the accumulated delay time in nanoseconds.
581 */
582 struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */
583 u64 blkio_delay; /* wait for sync block io completion */
584 u64 swapin_delay; /* wait for swapin block io completion */
585 u32 blkio_count; /* total count of the number of sync block */
586 /* io operations performed */
587 u32 swapin_count; /* total count of the number of swapin block */
588 /* io operations performed */
Shailabh Nagarca74e922006-07-14 00:24:36 -0700589};
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700590#endif /* CONFIG_TASK_DELAY_ACCT */
591
592static inline int sched_info_on(void)
593{
594#ifdef CONFIG_SCHEDSTATS
595 return 1;
596#elif defined(CONFIG_TASK_DELAY_ACCT)
597 extern int delayacct_on;
598 return delayacct_on;
599#else
600 return 0;
Shailabh Nagarca74e922006-07-14 00:24:36 -0700601#endif
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700602}
Shailabh Nagarca74e922006-07-14 00:24:36 -0700603
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604enum idle_type
605{
606 SCHED_IDLE,
607 NOT_IDLE,
608 NEWLY_IDLE,
609 MAX_IDLE_TYPES
610};
611
612/*
613 * sched-domains (multiprocessor balancing) declarations:
614 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615#define SCHED_LOAD_SCALE 128UL /* increase resolution of load */
616
Peter Williams2dd73a42006-06-27 02:54:34 -0700617#ifdef CONFIG_SMP
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618#define SD_LOAD_BALANCE 1 /* Do load balancing on this domain. */
619#define SD_BALANCE_NEWIDLE 2 /* Balance when about to become idle */
620#define SD_BALANCE_EXEC 4 /* Balance on exec */
Nick Piggin147cbb42005-06-25 14:57:19 -0700621#define SD_BALANCE_FORK 8 /* Balance on fork, clone */
622#define SD_WAKE_IDLE 16 /* Wake to idle CPU on task wakeup */
623#define SD_WAKE_AFFINE 32 /* Wake task to waking CPU */
624#define SD_WAKE_BALANCE 64 /* Perform balancing at task wakeup */
625#define SD_SHARE_CPUPOWER 128 /* Domain members share cpu power */
Siddha, Suresh B5c45bf22006-06-27 02:54:42 -0700626#define SD_POWERSAVINGS_BALANCE 256 /* Balance for power savings */
627
628#define BALANCE_FOR_POWER ((sched_mc_power_savings || sched_smt_power_savings) \
629 ? SD_POWERSAVINGS_BALANCE : 0)
630
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631
632struct sched_group {
633 struct sched_group *next; /* Must be a circular list */
634 cpumask_t cpumask;
635
636 /*
637 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
638 * single CPU. This is read only (except for setup, hotplug CPU).
639 */
640 unsigned long cpu_power;
641};
642
643struct sched_domain {
644 /* These fields must be setup */
645 struct sched_domain *parent; /* top domain must be null terminated */
646 struct sched_group *groups; /* the balancing groups of the domain */
647 cpumask_t span; /* span of all CPUs in this domain */
648 unsigned long min_interval; /* Minimum balance interval ms */
649 unsigned long max_interval; /* Maximum balance interval ms */
650 unsigned int busy_factor; /* less balancing by factor if busy */
651 unsigned int imbalance_pct; /* No balance until over watermark */
652 unsigned long long cache_hot_time; /* Task considered cache hot (ns) */
653 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */
654 unsigned int per_cpu_gain; /* CPU % gained by adding domain cpus */
Nick Piggin78979862005-06-25 14:57:13 -0700655 unsigned int busy_idx;
656 unsigned int idle_idx;
657 unsigned int newidle_idx;
658 unsigned int wake_idx;
Nick Piggin147cbb42005-06-25 14:57:19 -0700659 unsigned int forkexec_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660 int flags; /* See SD_* */
661
662 /* Runtime fields. */
663 unsigned long last_balance; /* init to jiffies. units in jiffies */
664 unsigned int balance_interval; /* initialise to 1. units in ms. */
665 unsigned int nr_balance_failed; /* initialise to 0 */
666
667#ifdef CONFIG_SCHEDSTATS
668 /* load_balance() stats */
669 unsigned long lb_cnt[MAX_IDLE_TYPES];
670 unsigned long lb_failed[MAX_IDLE_TYPES];
671 unsigned long lb_balanced[MAX_IDLE_TYPES];
672 unsigned long lb_imbalance[MAX_IDLE_TYPES];
673 unsigned long lb_gained[MAX_IDLE_TYPES];
674 unsigned long lb_hot_gained[MAX_IDLE_TYPES];
675 unsigned long lb_nobusyg[MAX_IDLE_TYPES];
676 unsigned long lb_nobusyq[MAX_IDLE_TYPES];
677
678 /* Active load balancing */
679 unsigned long alb_cnt;
680 unsigned long alb_failed;
681 unsigned long alb_pushed;
682
Nick Piggin68767a02005-06-25 14:57:20 -0700683 /* SD_BALANCE_EXEC stats */
684 unsigned long sbe_cnt;
685 unsigned long sbe_balanced;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686 unsigned long sbe_pushed;
687
Nick Piggin68767a02005-06-25 14:57:20 -0700688 /* SD_BALANCE_FORK stats */
689 unsigned long sbf_cnt;
690 unsigned long sbf_balanced;
691 unsigned long sbf_pushed;
692
Linus Torvalds1da177e2005-04-16 15:20:36 -0700693 /* try_to_wake_up() stats */
694 unsigned long ttwu_wake_remote;
695 unsigned long ttwu_move_affine;
696 unsigned long ttwu_move_balance;
697#endif
698};
699
Srivatsa Vaddagiri51888ca2006-06-27 02:54:38 -0700700extern int partition_sched_domains(cpumask_t *partition1,
Dinakar Guniguntala1a20ff22005-06-25 14:57:33 -0700701 cpumask_t *partition2);
akpm@osdl.org198e2f12006-01-12 01:05:30 -0800702
703/*
704 * Maximum cache size the migration-costs auto-tuning code will
705 * search from:
706 */
707extern unsigned int max_cache_size;
708
709#endif /* CONFIG_SMP */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700710
711
712struct io_context; /* See blkdev.h */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713struct cpuset;
714
715#define NGROUPS_SMALL 32
716#define NGROUPS_PER_BLOCK ((int)(PAGE_SIZE / sizeof(gid_t)))
717struct group_info {
718 int ngroups;
719 atomic_t usage;
720 gid_t small_block[NGROUPS_SMALL];
721 int nblocks;
722 gid_t *blocks[0];
723};
724
725/*
726 * get_group_info() must be called with the owning task locked (via task_lock())
727 * when task != current. The reason being that the vast majority of callers are
728 * looking at current->group_info, which can not be changed except by the
729 * current task. Changing current->group_info requires the task lock, too.
730 */
731#define get_group_info(group_info) do { \
732 atomic_inc(&(group_info)->usage); \
733} while (0)
734
735#define put_group_info(group_info) do { \
736 if (atomic_dec_and_test(&(group_info)->usage)) \
737 groups_free(group_info); \
738} while (0)
739
David Howells3e301482005-06-23 22:00:56 -0700740extern struct group_info *groups_alloc(int gidsetsize);
741extern void groups_free(struct group_info *group_info);
742extern int set_current_groups(struct group_info *group_info);
743extern int groups_search(struct group_info *group_info, gid_t grp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744/* access the groups "array" with this macro */
745#define GROUP_AT(gi, i) \
746 ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
747
Chen, Kenneth W383f2832005-09-09 13:02:02 -0700748#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
Ingo Molnar36c8b582006-07-03 00:25:41 -0700749extern void prefetch_stack(struct task_struct *t);
Chen, Kenneth W383f2832005-09-09 13:02:02 -0700750#else
751static inline void prefetch_stack(struct task_struct *t) { }
752#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753
754struct audit_context; /* See audit.c */
755struct mempolicy;
Jens Axboeb92ce552006-04-11 13:52:07 +0200756struct pipe_inode_info;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757
Con Kolivas3dee3862006-03-31 02:31:23 -0800758enum sleep_type {
759 SLEEP_NORMAL,
760 SLEEP_NONINTERACTIVE,
761 SLEEP_INTERACTIVE,
762 SLEEP_INTERRUPTED,
763};
764
Ingo Molnar70b97a72006-07-03 00:25:42 -0700765struct prio_array;
766
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767struct task_struct {
768 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
769 struct thread_info *thread_info;
770 atomic_t usage;
771 unsigned long flags; /* per process flags, defined below */
772 unsigned long ptrace;
773
Paolo 'Blaisorblade' Giarrusso36772092005-05-05 16:16:12 -0700774 int lock_depth; /* BKL lock depth */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700775
Peter Williams2dd73a42006-06-27 02:54:34 -0700776#ifdef CONFIG_SMP
777#ifdef __ARCH_WANT_UNLOCKED_CTXSW
Nick Piggin4866cde2005-06-25 14:57:23 -0700778 int oncpu;
779#endif
Peter Williams2dd73a42006-06-27 02:54:34 -0700780#endif
781 int load_weight; /* for niceness load balancing purposes */
Ingo Molnarb29739f2006-06-27 02:54:51 -0700782 int prio, static_prio, normal_prio;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700783 struct list_head run_list;
Ingo Molnar70b97a72006-07-03 00:25:42 -0700784 struct prio_array *array;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785
Jens Axboe22e2c502005-06-27 10:55:12 +0200786 unsigned short ioprio;
Alexey Dobriyan6c5c9342006-09-29 01:59:40 -0700787#ifdef CONFIG_BLK_DEV_IO_TRACE
Jens Axboe2056a782006-03-23 20:00:26 +0100788 unsigned int btrace_seq;
Alexey Dobriyan6c5c9342006-09-29 01:59:40 -0700789#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790 unsigned long sleep_avg;
791 unsigned long long timestamp, last_ran;
792 unsigned long long sched_time; /* sched_clock time spent running */
Con Kolivas3dee3862006-03-31 02:31:23 -0800793 enum sleep_type sleep_type;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794
795 unsigned long policy;
796 cpumask_t cpus_allowed;
797 unsigned int time_slice, first_time_slice;
798
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700799#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800 struct sched_info sched_info;
801#endif
802
803 struct list_head tasks;
804 /*
805 * ptrace_list/ptrace_children forms the list of my children
806 * that were stolen by a ptracer.
807 */
808 struct list_head ptrace_children;
809 struct list_head ptrace_list;
810
811 struct mm_struct *mm, *active_mm;
812
813/* task state */
814 struct linux_binfmt *binfmt;
815 long exit_state;
816 int exit_code, exit_signal;
817 int pdeath_signal; /* The signal sent when the parent dies */
818 /* ??? */
819 unsigned long personality;
820 unsigned did_exec:1;
821 pid_t pid;
822 pid_t tgid;
Arjan van de Ven0a4254052006-09-26 10:52:38 +0200823
824#ifdef CONFIG_CC_STACKPROTECTOR
825 /* Canary value for the -fstack-protector gcc feature */
826 unsigned long stack_canary;
827#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828 /*
829 * pointers to (original) parent process, youngest child, younger sibling,
830 * older sibling, respectively. (p->father can be replaced with
831 * p->parent->pid)
832 */
833 struct task_struct *real_parent; /* real parent process (when being debugged) */
834 struct task_struct *parent; /* parent process */
835 /*
836 * children/sibling forms the list of my children plus the
837 * tasks I'm ptracing.
838 */
839 struct list_head children; /* list of my children */
840 struct list_head sibling; /* linkage in my parent's children list */
841 struct task_struct *group_leader; /* threadgroup leader */
842
843 /* PID/PID hash table linkage. */
Eric W. Biederman92476d72006-03-31 02:31:42 -0800844 struct pid_link pids[PIDTYPE_MAX];
Oleg Nesterov47e65322006-03-28 16:11:25 -0800845 struct list_head thread_group;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846
847 struct completion *vfork_done; /* for vfork() */
848 int __user *set_child_tid; /* CLONE_CHILD_SETTID */
849 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
850
851 unsigned long rt_priority;
852 cputime_t utime, stime;
853 unsigned long nvcsw, nivcsw; /* context switch counts */
854 struct timespec start_time;
855/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
856 unsigned long min_flt, maj_flt;
857
858 cputime_t it_prof_expires, it_virt_expires;
859 unsigned long long it_sched_expires;
860 struct list_head cpu_timers[3];
861
862/* process credentials */
863 uid_t uid,euid,suid,fsuid;
864 gid_t gid,egid,sgid,fsgid;
865 struct group_info *group_info;
866 kernel_cap_t cap_effective, cap_inheritable, cap_permitted;
867 unsigned keep_capabilities:1;
868 struct user_struct *user;
869#ifdef CONFIG_KEYS
David Howellsb5f545c2006-01-08 01:02:47 -0800870 struct key *request_key_auth; /* assumed request_key authority */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700871 struct key *thread_keyring; /* keyring private to this thread */
David Howells3e301482005-06-23 22:00:56 -0700872 unsigned char jit_keyring; /* default keyring to attach requested keys to */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700873#endif
Arjan van de Vene07e23e2006-09-26 10:52:36 +0200874 /*
875 * fpu_counter contains the number of consecutive context switches
876 * that the FPU is used. If this is over a threshold, the lazy fpu
877 * saving becomes unlazy to save the trap. This is an unsigned char
878 * so that after 256 times the counter wraps and the behavior turns
879 * lazy again; this to deal with bursty apps that only use FPU for
880 * a short time
881 */
882 unsigned char fpu_counter;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700883 int oomkilladj; /* OOM kill score adjustment (bit shift). */
Paolo 'Blaisorblade' Giarrusso36772092005-05-05 16:16:12 -0700884 char comm[TASK_COMM_LEN]; /* executable name excluding path
885 - access with [gs]et_task_comm (which lock
886 it with task_lock())
887 - initialized normally by flush_old_exec */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700888/* file system info */
889 int link_count, total_link_count;
Alexey Dobriyan3d5b6fc2006-09-29 01:59:40 -0700890#ifdef CONFIG_SYSVIPC
Linus Torvalds1da177e2005-04-16 15:20:36 -0700891/* ipc stuff */
892 struct sysv_sem sysvsem;
Alexey Dobriyan3d5b6fc2006-09-29 01:59:40 -0700893#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700894/* CPU-specific state of this task */
895 struct thread_struct thread;
896/* filesystem information */
897 struct fs_struct *fs;
898/* open file information */
899 struct files_struct *files;
900/* namespace */
901 struct namespace *namespace;
902/* signal handlers */
903 struct signal_struct *signal;
904 struct sighand_struct *sighand;
905
906 sigset_t blocked, real_blocked;
David Woodhouse150256d2006-01-18 17:43:57 -0800907 sigset_t saved_sigmask; /* To be restored with TIF_RESTORE_SIGMASK */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700908 struct sigpending pending;
909
910 unsigned long sas_ss_sp;
911 size_t sas_ss_size;
912 int (*notifier)(void *priv);
913 void *notifier_data;
914 sigset_t *notifier_mask;
915
916 void *security;
917 struct audit_context *audit_context;
918 seccomp_t seccomp;
919
920/* Thread group tracking */
921 u32 parent_exec_id;
922 u32 self_exec_id;
923/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
924 spinlock_t alloc_lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925
Ingo Molnarb29739f2006-06-27 02:54:51 -0700926 /* Protection of the PI data structures: */
927 spinlock_t pi_lock;
928
Ingo Molnar23f78d4a2006-06-27 02:54:53 -0700929#ifdef CONFIG_RT_MUTEXES
930 /* PI waiters blocked on a rt_mutex held by this task */
931 struct plist_head pi_waiters;
932 /* Deadlock detection and priority inheritance handling */
933 struct rt_mutex_waiter *pi_blocked_on;
Ingo Molnar23f78d4a2006-06-27 02:54:53 -0700934#endif
935
Ingo Molnar408894e2006-01-09 15:59:20 -0800936#ifdef CONFIG_DEBUG_MUTEXES
937 /* mutex deadlock detection */
938 struct mutex_waiter *blocked_on;
939#endif
Ingo Molnarde30a2b2006-07-03 00:24:42 -0700940#ifdef CONFIG_TRACE_IRQFLAGS
941 unsigned int irq_events;
942 int hardirqs_enabled;
943 unsigned long hardirq_enable_ip;
944 unsigned int hardirq_enable_event;
945 unsigned long hardirq_disable_ip;
946 unsigned int hardirq_disable_event;
947 int softirqs_enabled;
948 unsigned long softirq_disable_ip;
949 unsigned int softirq_disable_event;
950 unsigned long softirq_enable_ip;
951 unsigned int softirq_enable_event;
952 int hardirq_context;
953 int softirq_context;
954#endif
Ingo Molnarfbb9ce952006-07-03 00:24:50 -0700955#ifdef CONFIG_LOCKDEP
956# define MAX_LOCK_DEPTH 30UL
957 u64 curr_chain_key;
958 int lockdep_depth;
959 struct held_lock held_locks[MAX_LOCK_DEPTH];
960 unsigned int lockdep_recursion;
961#endif
Ingo Molnar408894e2006-01-09 15:59:20 -0800962
Linus Torvalds1da177e2005-04-16 15:20:36 -0700963/* journalling filesystem info */
964 void *journal_info;
965
966/* VM state */
967 struct reclaim_state *reclaim_state;
968
Linus Torvalds1da177e2005-04-16 15:20:36 -0700969 struct backing_dev_info *backing_dev_info;
970
971 struct io_context *io_context;
972
973 unsigned long ptrace_message;
974 siginfo_t *last_siginfo; /* For ptrace use. */
975/*
976 * current io wait handle: wait queue entry to use for io waits
977 * If this thread is processing aio, this points at the waitqueue
978 * inside the currently handled kiocb. It may be NULL (i.e. default
979 * to a stack based synchronous wait) if its doing sync IO.
980 */
981 wait_queue_t *io_wait;
982/* i/o counters(bytes read/written, #syscalls */
983 u64 rchar, wchar, syscr, syscw;
Jay Lan8f0ab512006-09-30 23:28:59 -0700984#if defined(CONFIG_TASK_XACCT)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985 u64 acct_rss_mem1; /* accumulated rss usage */
986 u64 acct_vm_mem1; /* accumulated virtual memory usage */
Jay Landb5fed262006-09-30 23:29:00 -0700987 cputime_t acct_stimexpd;/* stime since last update */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700988#endif
989#ifdef CONFIG_NUMA
990 struct mempolicy *mempolicy;
991 short il_next;
992#endif
993#ifdef CONFIG_CPUSETS
994 struct cpuset *cpuset;
995 nodemask_t mems_allowed;
996 int cpuset_mems_generation;
Paul Jackson825a46a2006-03-24 03:16:03 -0800997 int cpuset_mem_spread_rotor;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700998#endif
Ingo Molnar0771dfe2006-03-27 01:16:22 -0800999 struct robust_list_head __user *robust_list;
Ingo Molnar34f192c2006-03-27 01:16:24 -08001000#ifdef CONFIG_COMPAT
1001 struct compat_robust_list_head __user *compat_robust_list;
1002#endif
Ingo Molnarc87e2832006-06-27 02:54:58 -07001003 struct list_head pi_state_list;
1004 struct futex_pi_state *pi_state_cache;
Ingo Molnar0771dfe2006-03-27 01:16:22 -08001005
Jens Axboe22e2c502005-06-27 10:55:12 +02001006 atomic_t fs_excl; /* holding fs exclusive resources */
Ingo Molnare56d0902006-01-08 01:01:37 -08001007 struct rcu_head rcu;
Jens Axboeb92ce552006-04-11 13:52:07 +02001008
1009 /*
1010 * cache last used pipe for splice
1011 */
1012 struct pipe_inode_info *splice_pipe;
Shailabh Nagarca74e922006-07-14 00:24:36 -07001013#ifdef CONFIG_TASK_DELAY_ACCT
1014 struct task_delay_info *delays;
1015#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001016};
1017
1018static inline pid_t process_group(struct task_struct *tsk)
1019{
1020 return tsk->signal->pgrp;
1021}
1022
Eric W. Biederman22c935f2006-10-02 02:17:09 -07001023static inline struct pid *task_pid(struct task_struct *task)
1024{
1025 return task->pids[PIDTYPE_PID].pid;
1026}
1027
1028static inline struct pid *task_tgid(struct task_struct *task)
1029{
1030 return task->group_leader->pids[PIDTYPE_PID].pid;
1031}
1032
1033static inline struct pid *task_pgrp(struct task_struct *task)
1034{
1035 return task->group_leader->pids[PIDTYPE_PGID].pid;
1036}
1037
1038static inline struct pid *task_session(struct task_struct *task)
1039{
1040 return task->group_leader->pids[PIDTYPE_SID].pid;
1041}
1042
Linus Torvalds1da177e2005-04-16 15:20:36 -07001043/**
1044 * pid_alive - check that a task structure is not stale
1045 * @p: Task structure to be checked.
1046 *
1047 * Test if a process is not yet dead (at most zombie state)
1048 * If pid_alive fails, then pointers within the task structure
1049 * can be stale and must not be dereferenced.
1050 */
1051static inline int pid_alive(struct task_struct *p)
1052{
Eric W. Biederman92476d72006-03-31 02:31:42 -08001053 return p->pids[PIDTYPE_PID].pid != NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001054}
1055
Sukadev Bhattiproluf400e192006-09-29 02:00:07 -07001056/**
1057 * is_init - check if a task structure is the first user space
1058 * task the kernel created.
1059 * @p: Task structure to be checked.
1060 */
1061static inline int is_init(struct task_struct *tsk)
1062{
1063 return tsk->pid == 1;
1064}
1065
Linus Torvalds1da177e2005-04-16 15:20:36 -07001066extern void free_task(struct task_struct *tsk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001067#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
Ingo Molnare56d0902006-01-08 01:01:37 -08001068
Andrew Morton158d9eb2006-03-31 02:31:34 -08001069extern void __put_task_struct(struct task_struct *t);
Ingo Molnare56d0902006-01-08 01:01:37 -08001070
1071static inline void put_task_struct(struct task_struct *t)
1072{
1073 if (atomic_dec_and_test(&t->usage))
Eric W. Biederman8c7904a2006-03-31 02:31:37 -08001074 __put_task_struct(t);
Ingo Molnare56d0902006-01-08 01:01:37 -08001075}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001076
1077/*
1078 * Per process flags
1079 */
1080#define PF_ALIGNWARN 0x00000001 /* Print alignment warning msgs */
1081 /* Not implemented yet, only for 486*/
1082#define PF_STARTING 0x00000002 /* being created */
1083#define PF_EXITING 0x00000004 /* getting shut down */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001084#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
1085#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
1086#define PF_DUMPCORE 0x00000200 /* dumped core */
1087#define PF_SIGNALED 0x00000400 /* killed by a signal */
1088#define PF_MEMALLOC 0x00000800 /* Allocating memory */
1089#define PF_FLUSHER 0x00001000 /* responsible for disk writeback */
1090#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
1091#define PF_FREEZE 0x00004000 /* this task is being frozen for suspend now */
1092#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
1093#define PF_FROZEN 0x00010000 /* frozen for system suspend */
1094#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
1095#define PF_KSWAPD 0x00040000 /* I am kswapd */
1096#define PF_SWAPOFF 0x00080000 /* I am in swapoff */
1097#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
Jens Axboeb31dc662006-06-13 08:26:10 +02001098#define PF_BORROWED_MM 0x00200000 /* I am a kthread doing use_mm */
1099#define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */
1100#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1101#define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */
1102#define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */
Paul Jacksonc61afb12006-03-24 03:16:08 -08001103#define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */
Thomas Gleixner61a87122006-06-27 02:54:56 -07001104#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001105
1106/*
1107 * Only the _current_ task can read/write to tsk->flags, but other
1108 * tasks can access tsk->flags in readonly mode for example
1109 * with tsk_used_math (like during threaded core dumping).
1110 * There is however an exception to this rule during ptrace
1111 * or during fork: the ptracer task is allowed to write to the
1112 * child->flags of its traced child (same goes for fork, the parent
1113 * can write to the child->flags), because we're guaranteed the
1114 * child is not running and in turn not changing child->flags
1115 * at the same time the parent does it.
1116 */
1117#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1118#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1119#define clear_used_math() clear_stopped_child_used_math(current)
1120#define set_used_math() set_stopped_child_used_math(current)
1121#define conditional_stopped_child_used_math(condition, child) \
1122 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1123#define conditional_used_math(condition) \
1124 conditional_stopped_child_used_math(condition, current)
1125#define copy_to_stopped_child_used_math(child) \
1126 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1127/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1128#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1129#define used_math() tsk_used_math(current)
1130
1131#ifdef CONFIG_SMP
Ingo Molnar36c8b582006-07-03 00:25:41 -07001132extern int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001133#else
Ingo Molnar36c8b582006-07-03 00:25:41 -07001134static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001135{
Paul Jackson4098f992005-10-30 15:03:21 -08001136 if (!cpu_isset(0, new_mask))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001137 return -EINVAL;
1138 return 0;
1139}
1140#endif
1141
1142extern unsigned long long sched_clock(void);
Ingo Molnar36c8b582006-07-03 00:25:41 -07001143extern unsigned long long
1144current_sched_time(const struct task_struct *current_task);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001145
1146/* sched_exec is called by processes performing an exec */
1147#ifdef CONFIG_SMP
1148extern void sched_exec(void);
1149#else
1150#define sched_exec() {}
1151#endif
1152
1153#ifdef CONFIG_HOTPLUG_CPU
1154extern void idle_task_exit(void);
1155#else
1156static inline void idle_task_exit(void) {}
1157#endif
1158
1159extern void sched_idle_next(void);
Ingo Molnarb29739f2006-06-27 02:54:51 -07001160
1161#ifdef CONFIG_RT_MUTEXES
Ingo Molnar36c8b582006-07-03 00:25:41 -07001162extern int rt_mutex_getprio(struct task_struct *p);
1163extern void rt_mutex_setprio(struct task_struct *p, int prio);
1164extern void rt_mutex_adjust_pi(struct task_struct *p);
Ingo Molnarb29739f2006-06-27 02:54:51 -07001165#else
Ingo Molnar36c8b582006-07-03 00:25:41 -07001166static inline int rt_mutex_getprio(struct task_struct *p)
Ingo Molnarb29739f2006-06-27 02:54:51 -07001167{
1168 return p->normal_prio;
1169}
Thomas Gleixner95e02ca2006-06-27 02:55:02 -07001170# define rt_mutex_adjust_pi(p) do { } while (0)
Ingo Molnarb29739f2006-06-27 02:54:51 -07001171#endif
1172
Ingo Molnar36c8b582006-07-03 00:25:41 -07001173extern void set_user_nice(struct task_struct *p, long nice);
1174extern int task_prio(const struct task_struct *p);
1175extern int task_nice(const struct task_struct *p);
1176extern int can_nice(const struct task_struct *p, const int nice);
1177extern int task_curr(const struct task_struct *p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001178extern int idle_cpu(int cpu);
1179extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
Ingo Molnar36c8b582006-07-03 00:25:41 -07001180extern struct task_struct *idle_task(int cpu);
1181extern struct task_struct *curr_task(int cpu);
1182extern void set_curr_task(int cpu, struct task_struct *p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001183
1184void yield(void);
1185
1186/*
1187 * The default (Linux) execution domain.
1188 */
1189extern struct exec_domain default_exec_domain;
1190
1191union thread_union {
1192 struct thread_info thread_info;
1193 unsigned long stack[THREAD_SIZE/sizeof(long)];
1194};
1195
1196#ifndef __HAVE_ARCH_KSTACK_END
1197static inline int kstack_end(void *addr)
1198{
1199 /* Reliable end of stack detection:
1200 * Some APM bios versions misalign the stack
1201 */
1202 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1203}
1204#endif
1205
1206extern union thread_union init_thread_union;
1207extern struct task_struct init_task;
1208
1209extern struct mm_struct init_mm;
1210
1211#define find_task_by_pid(nr) find_task_by_pid_type(PIDTYPE_PID, nr)
1212extern struct task_struct *find_task_by_pid_type(int type, int pid);
1213extern void set_special_pids(pid_t session, pid_t pgrp);
1214extern void __set_special_pids(pid_t session, pid_t pgrp);
1215
1216/* per-UID process charging. */
1217extern struct user_struct * alloc_uid(uid_t);
1218static inline struct user_struct *get_uid(struct user_struct *u)
1219{
1220 atomic_inc(&u->__count);
1221 return u;
1222}
1223extern void free_uid(struct user_struct *);
1224extern void switch_uid(struct user_struct *);
1225
1226#include <asm/current.h>
1227
Atsushi Nemoto3171a032006-09-29 02:00:32 -07001228extern void do_timer(unsigned long ticks);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001229
1230extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state));
1231extern int FASTCALL(wake_up_process(struct task_struct * tsk));
1232extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
1233 unsigned long clone_flags));
1234#ifdef CONFIG_SMP
1235 extern void kick_process(struct task_struct *tsk);
1236#else
1237 static inline void kick_process(struct task_struct *tsk) { }
1238#endif
Ingo Molnar36c8b582006-07-03 00:25:41 -07001239extern void FASTCALL(sched_fork(struct task_struct * p, int clone_flags));
1240extern void FASTCALL(sched_exit(struct task_struct * p));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001241
1242extern int in_group_p(gid_t);
1243extern int in_egroup_p(gid_t);
1244
1245extern void proc_caches_init(void);
1246extern void flush_signals(struct task_struct *);
1247extern void flush_signal_handlers(struct task_struct *, int force_default);
1248extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1249
1250static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1251{
1252 unsigned long flags;
1253 int ret;
1254
1255 spin_lock_irqsave(&tsk->sighand->siglock, flags);
1256 ret = dequeue_signal(tsk, mask, info);
1257 spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1258
1259 return ret;
1260}
1261
1262extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1263 sigset_t *mask);
1264extern void unblock_all_signals(void);
1265extern void release_task(struct task_struct * p);
1266extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1267extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
1268extern int force_sigsegv(int, struct task_struct *);
1269extern int force_sig_info(int, struct siginfo *, struct task_struct *);
Eric W. Biedermanc4b92fc2006-10-02 02:17:10 -07001270extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1271extern int kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1272extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
1273extern int kill_pgrp(struct pid *pid, int sig, int priv);
1274extern int kill_pid(struct pid *pid, int sig, int priv);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001275extern int __kill_pg_info(int sig, struct siginfo *info, pid_t pgrp);
1276extern int kill_pg_info(int, struct siginfo *, pid_t);
1277extern int kill_proc_info(int, struct siginfo *, pid_t);
David Quigley8f95dc52006-06-30 01:55:47 -07001278extern int kill_proc_info_as_uid(int, struct siginfo *, pid_t, uid_t, uid_t, u32);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001279extern void do_notify_parent(struct task_struct *, int);
1280extern void force_sig(int, struct task_struct *);
1281extern void force_sig_specific(int, struct task_struct *);
1282extern int send_sig(int, struct task_struct *, int);
1283extern void zap_other_threads(struct task_struct *p);
1284extern int kill_pg(pid_t, int, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001285extern int kill_proc(pid_t, int, int);
1286extern struct sigqueue *sigqueue_alloc(void);
1287extern void sigqueue_free(struct sigqueue *);
1288extern int send_sigqueue(int, struct sigqueue *, struct task_struct *);
1289extern int send_group_sigqueue(int, struct sigqueue *, struct task_struct *);
Oleg Nesterov9ac95f22006-02-09 22:41:50 +03001290extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001291extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1292
1293/* These can be the second arg to send_sig_info/send_group_sig_info. */
1294#define SEND_SIG_NOINFO ((struct siginfo *) 0)
1295#define SEND_SIG_PRIV ((struct siginfo *) 1)
1296#define SEND_SIG_FORCED ((struct siginfo *) 2)
1297
Oleg Nesterov621d3122005-10-30 15:03:45 -08001298static inline int is_si_special(const struct siginfo *info)
1299{
1300 return info <= SEND_SIG_FORCED;
1301}
1302
Linus Torvalds1da177e2005-04-16 15:20:36 -07001303/* True if we are on the alternate signal stack. */
1304
1305static inline int on_sig_stack(unsigned long sp)
1306{
1307 return (sp - current->sas_ss_sp < current->sas_ss_size);
1308}
1309
1310static inline int sas_ss_flags(unsigned long sp)
1311{
1312 return (current->sas_ss_size == 0 ? SS_DISABLE
1313 : on_sig_stack(sp) ? SS_ONSTACK : 0);
1314}
1315
Linus Torvalds1da177e2005-04-16 15:20:36 -07001316/*
1317 * Routines for handling mm_structs
1318 */
1319extern struct mm_struct * mm_alloc(void);
1320
1321/* mmdrop drops the mm and the page tables */
1322extern void FASTCALL(__mmdrop(struct mm_struct *));
1323static inline void mmdrop(struct mm_struct * mm)
1324{
1325 if (atomic_dec_and_test(&mm->mm_count))
1326 __mmdrop(mm);
1327}
1328
1329/* mmput gets rid of the mappings and all user-space */
1330extern void mmput(struct mm_struct *);
1331/* Grab a reference to a task's mm, if it is not already going away */
1332extern struct mm_struct *get_task_mm(struct task_struct *task);
1333/* Remove the current tasks stale references to the old mm_struct */
1334extern void mm_release(struct task_struct *, struct mm_struct *);
1335
1336extern int copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1337extern void flush_thread(void);
1338extern void exit_thread(void);
1339
Linus Torvalds1da177e2005-04-16 15:20:36 -07001340extern void exit_files(struct task_struct *);
Oleg Nesterov6b3934e2006-03-28 16:11:16 -08001341extern void __cleanup_signal(struct signal_struct *);
Oleg Nesterova7e53282006-03-28 16:11:27 -08001342extern void __cleanup_sighand(struct sighand_struct *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001343extern void exit_itimers(struct signal_struct *);
1344
1345extern NORET_TYPE void do_group_exit(int);
1346
Linus Torvalds1da177e2005-04-16 15:20:36 -07001347extern void daemonize(const char *, ...);
1348extern int allow_signal(int);
1349extern int disallow_signal(int);
Ingo Molnar36c8b582006-07-03 00:25:41 -07001350extern struct task_struct *child_reaper;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001351
1352extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1353extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
Ingo Molnar36c8b582006-07-03 00:25:41 -07001354struct task_struct *fork_idle(int);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001355
1356extern void set_task_comm(struct task_struct *tsk, char *from);
1357extern void get_task_comm(char *to, struct task_struct *tsk);
1358
1359#ifdef CONFIG_SMP
Ingo Molnar36c8b582006-07-03 00:25:41 -07001360extern void wait_task_inactive(struct task_struct * p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001361#else
1362#define wait_task_inactive(p) do { } while (0)
1363#endif
1364
1365#define remove_parent(p) list_del_init(&(p)->sibling)
Oleg Nesterov8fafabd2006-03-28 16:11:05 -08001366#define add_parent(p) list_add_tail(&(p)->sibling,&(p)->parent->children)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001367
Eric W. Biederman5e85d4a2006-04-18 22:20:16 -07001368#define next_task(p) list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001369
1370#define for_each_process(p) \
1371 for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1372
1373/*
1374 * Careful: do_each_thread/while_each_thread is a double loop so
1375 * 'break' will not work as expected - use goto instead.
1376 */
1377#define do_each_thread(g, t) \
1378 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1379
1380#define while_each_thread(g, t) \
1381 while ((t = next_thread(t)) != g)
1382
Eric W. Biedermande12a782006-04-10 17:16:49 -06001383/* de_thread depends on thread_group_leader not being a pid based check */
1384#define thread_group_leader(p) (p == p->group_leader)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001385
Eric W. Biederman0804ef42006-10-02 02:17:04 -07001386/* Do to the insanities of de_thread it is possible for a process
1387 * to have the pid of the thread group leader without actually being
1388 * the thread group leader. For iteration through the pids in proc
1389 * all we care about is that we have a task with the appropriate
1390 * pid, we don't actually care if we have the right task.
1391 */
1392static inline int has_group_leader_pid(struct task_struct *p)
1393{
1394 return p->pid == p->tgid;
1395}
1396
Ingo Molnar36c8b582006-07-03 00:25:41 -07001397static inline struct task_struct *next_thread(const struct task_struct *p)
Oleg Nesterov47e65322006-03-28 16:11:25 -08001398{
1399 return list_entry(rcu_dereference(p->thread_group.next),
Ingo Molnar36c8b582006-07-03 00:25:41 -07001400 struct task_struct, thread_group);
Oleg Nesterov47e65322006-03-28 16:11:25 -08001401}
1402
Ingo Molnar36c8b582006-07-03 00:25:41 -07001403static inline int thread_group_empty(struct task_struct *p)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001404{
Oleg Nesterov47e65322006-03-28 16:11:25 -08001405 return list_empty(&p->thread_group);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001406}
1407
1408#define delay_group_leader(p) \
1409 (thread_group_leader(p) && !thread_group_empty(p))
1410
Linus Torvalds1da177e2005-04-16 15:20:36 -07001411/*
Eric W. Biederman260ea102006-06-23 02:05:18 -07001412 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
Jens Axboe22e2c502005-06-27 10:55:12 +02001413 * subscriptions and synchronises with wait4(). Also used in procfs. Also
Paul Jackson053199e2005-10-30 15:02:30 -08001414 * pins the final release of task.io_context. Also protects ->cpuset.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001415 *
1416 * Nests both inside and outside of read_lock(&tasklist_lock).
1417 * It must not be nested with write_lock_irq(&tasklist_lock),
1418 * neither inside nor outside.
1419 */
1420static inline void task_lock(struct task_struct *p)
1421{
1422 spin_lock(&p->alloc_lock);
1423}
1424
1425static inline void task_unlock(struct task_struct *p)
1426{
1427 spin_unlock(&p->alloc_lock);
1428}
1429
Oleg Nesterovf63ee722006-03-28 16:11:13 -08001430extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
1431 unsigned long *flags);
1432
1433static inline void unlock_task_sighand(struct task_struct *tsk,
1434 unsigned long *flags)
1435{
1436 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
1437}
1438
Al Virof0373602005-11-13 16:06:57 -08001439#ifndef __HAVE_THREAD_FUNCTIONS
1440
Al Viroa1261f52005-11-13 16:06:55 -08001441#define task_thread_info(task) (task)->thread_info
Al Viro9fc65872006-01-12 01:05:34 -08001442#define task_stack_page(task) ((void*)((task)->thread_info))
Al Viroa1261f52005-11-13 16:06:55 -08001443
Al Viro10ebffd2005-11-13 16:06:56 -08001444static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
1445{
1446 *task_thread_info(p) = *task_thread_info(org);
1447 task_thread_info(p)->task = p;
1448}
1449
1450static inline unsigned long *end_of_stack(struct task_struct *p)
1451{
1452 return (unsigned long *)(p->thread_info + 1);
1453}
1454
Al Virof0373602005-11-13 16:06:57 -08001455#endif
1456
Linus Torvalds1da177e2005-04-16 15:20:36 -07001457/* set thread flags in other task's structures
1458 * - see asm/thread_info.h for TIF_xxxx flags available
1459 */
1460static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1461{
Al Viroa1261f52005-11-13 16:06:55 -08001462 set_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001463}
1464
1465static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1466{
Al Viroa1261f52005-11-13 16:06:55 -08001467 clear_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001468}
1469
1470static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1471{
Al Viroa1261f52005-11-13 16:06:55 -08001472 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001473}
1474
1475static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1476{
Al Viroa1261f52005-11-13 16:06:55 -08001477 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001478}
1479
1480static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1481{
Al Viroa1261f52005-11-13 16:06:55 -08001482 return test_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001483}
1484
1485static inline void set_tsk_need_resched(struct task_struct *tsk)
1486{
1487 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1488}
1489
1490static inline void clear_tsk_need_resched(struct task_struct *tsk)
1491{
1492 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1493}
1494
1495static inline int signal_pending(struct task_struct *p)
1496{
1497 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1498}
1499
1500static inline int need_resched(void)
1501{
1502 return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1503}
1504
1505/*
1506 * cond_resched() and cond_resched_lock(): latency reduction via
1507 * explicit rescheduling in places that are safe. The return
1508 * value indicates whether a reschedule was done in fact.
1509 * cond_resched_lock() will drop the spinlock before scheduling,
1510 * cond_resched_softirq() will enable bhs before scheduling.
1511 */
1512extern int cond_resched(void);
1513extern int cond_resched_lock(spinlock_t * lock);
1514extern int cond_resched_softirq(void);
1515
1516/*
1517 * Does a critical section need to be broken due to another
1518 * task waiting?:
1519 */
1520#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
1521# define need_lockbreak(lock) ((lock)->break_lock)
1522#else
1523# define need_lockbreak(lock) 0
1524#endif
1525
1526/*
1527 * Does a critical section need to be broken due to another
1528 * task waiting or preemption being signalled:
1529 */
1530static inline int lock_need_resched(spinlock_t *lock)
1531{
1532 if (need_lockbreak(lock) || need_resched())
1533 return 1;
1534 return 0;
1535}
1536
1537/* Reevaluate whether the task has signals pending delivery.
1538 This is required every time the blocked sigset_t changes.
1539 callers must hold sighand->siglock. */
1540
1541extern FASTCALL(void recalc_sigpending_tsk(struct task_struct *t));
1542extern void recalc_sigpending(void);
1543
1544extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1545
1546/*
1547 * Wrappers for p->thread_info->cpu access. No-op on UP.
1548 */
1549#ifdef CONFIG_SMP
1550
1551static inline unsigned int task_cpu(const struct task_struct *p)
1552{
Al Viroa1261f52005-11-13 16:06:55 -08001553 return task_thread_info(p)->cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001554}
1555
1556static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1557{
Al Viroa1261f52005-11-13 16:06:55 -08001558 task_thread_info(p)->cpu = cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001559}
1560
1561#else
1562
1563static inline unsigned int task_cpu(const struct task_struct *p)
1564{
1565 return 0;
1566}
1567
1568static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1569{
1570}
1571
1572#endif /* CONFIG_SMP */
1573
1574#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1575extern void arch_pick_mmap_layout(struct mm_struct *mm);
1576#else
1577static inline void arch_pick_mmap_layout(struct mm_struct *mm)
1578{
1579 mm->mmap_base = TASK_UNMAPPED_BASE;
1580 mm->get_unmapped_area = arch_get_unmapped_area;
1581 mm->unmap_area = arch_unmap_area;
1582}
1583#endif
1584
1585extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
1586extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
1587
Siddha, Suresh B5c45bf22006-06-27 02:54:42 -07001588#include <linux/sysdev.h>
1589extern int sched_mc_power_savings, sched_smt_power_savings;
1590extern struct sysdev_attribute attr_sched_mc_power_savings, attr_sched_smt_power_savings;
1591extern int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls);
1592
Linus Torvalds1da177e2005-04-16 15:20:36 -07001593extern void normalize_rt_tasks(void);
1594
Linus Torvalds1da177e2005-04-16 15:20:36 -07001595#ifdef CONFIG_PM
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001596/*
1597 * Check if a process has been frozen
1598 */
1599static inline int frozen(struct task_struct *p)
1600{
1601 return p->flags & PF_FROZEN;
1602}
1603
1604/*
1605 * Check if there is a request to freeze a process
1606 */
1607static inline int freezing(struct task_struct *p)
1608{
1609 return p->flags & PF_FREEZE;
1610}
1611
1612/*
1613 * Request that a process be frozen
1614 * FIXME: SMP problem. We may not modify other process' flags!
1615 */
1616static inline void freeze(struct task_struct *p)
1617{
1618 p->flags |= PF_FREEZE;
1619}
1620
1621/*
Rafael J. Wysockia7ef7872006-08-05 12:13:42 -07001622 * Sometimes we may need to cancel the previous 'freeze' request
1623 */
1624static inline void do_not_freeze(struct task_struct *p)
1625{
1626 p->flags &= ~PF_FREEZE;
1627}
1628
1629/*
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001630 * Wake up a frozen process
1631 */
1632static inline int thaw_process(struct task_struct *p)
1633{
1634 if (frozen(p)) {
1635 p->flags &= ~PF_FROZEN;
1636 wake_up_process(p);
1637 return 1;
1638 }
1639 return 0;
1640}
1641
1642/*
1643 * freezing is complete, mark process as frozen
1644 */
1645static inline void frozen_process(struct task_struct *p)
1646{
1647 p->flags = (p->flags & ~PF_FREEZE) | PF_FROZEN;
1648}
1649
1650extern void refrigerator(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001651extern int freeze_processes(void);
1652extern void thaw_processes(void);
1653
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001654static inline int try_to_freeze(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001655{
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001656 if (freezing(current)) {
1657 refrigerator();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001658 return 1;
1659 } else
1660 return 0;
1661}
1662#else
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001663static inline int frozen(struct task_struct *p) { return 0; }
1664static inline int freezing(struct task_struct *p) { return 0; }
1665static inline void freeze(struct task_struct *p) { BUG(); }
1666static inline int thaw_process(struct task_struct *p) { return 1; }
1667static inline void frozen_process(struct task_struct *p) { BUG(); }
1668
1669static inline void refrigerator(void) {}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001670static inline int freeze_processes(void) { BUG(); return 0; }
1671static inline void thaw_processes(void) {}
1672
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001673static inline int try_to_freeze(void) { return 0; }
1674
Linus Torvalds1da177e2005-04-16 15:20:36 -07001675#endif /* CONFIG_PM */
1676#endif /* __KERNEL__ */
1677
1678#endif