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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 */
Serge E. Hallyn071df102006-10-02 02:18:17 -070027#define CLONE_NEWUTS 0x04000000 /* New utsname group? */
Kirill Korotaev25b21cb2006-10-02 02:18:19 -070028#define CLONE_NEWIPC 0x08000000 /* New ipcs */
David Woodhouseb7b3c762006-04-27 00:12:56 +010029
30/*
31 * Scheduling policies
32 */
33#define SCHED_NORMAL 0
34#define SCHED_FIFO 1
35#define SCHED_RR 2
36#define SCHED_BATCH 3
37
David Woodhousea3b67142006-04-25 14:54:40 +010038#ifdef __KERNEL__
David Woodhouseb7b3c762006-04-27 00:12:56 +010039
40struct sched_param {
41 int sched_priority;
42};
43
Linus Torvalds1da177e2005-04-16 15:20:36 -070044#include <asm/param.h> /* for HZ */
45
Linus Torvalds1da177e2005-04-16 15:20:36 -070046#include <linux/capability.h>
47#include <linux/threads.h>
48#include <linux/kernel.h>
49#include <linux/types.h>
50#include <linux/timex.h>
51#include <linux/jiffies.h>
52#include <linux/rbtree.h>
53#include <linux/thread_info.h>
54#include <linux/cpumask.h>
55#include <linux/errno.h>
56#include <linux/nodemask.h>
57
58#include <asm/system.h>
59#include <asm/semaphore.h>
60#include <asm/page.h>
61#include <asm/ptrace.h>
62#include <asm/mmu.h>
63#include <asm/cputime.h>
64
65#include <linux/smp.h>
66#include <linux/sem.h>
67#include <linux/signal.h>
68#include <linux/securebits.h>
69#include <linux/fs_struct.h>
70#include <linux/compiler.h>
71#include <linux/completion.h>
72#include <linux/pid.h>
73#include <linux/percpu.h>
74#include <linux/topology.h>
75#include <linux/seccomp.h>
Ingo Molnare56d0902006-01-08 01:01:37 -080076#include <linux/rcupdate.h>
Ingo Molnar0771dfe2006-03-27 01:16:22 -080077#include <linux/futex.h>
Ingo Molnar23f78d4a2006-06-27 02:54:53 -070078#include <linux/rtmutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070079
David Woodhousea3b67142006-04-25 14:54:40 +010080#include <linux/time.h>
81#include <linux/param.h>
82#include <linux/resource.h>
83#include <linux/timer.h>
84#include <linux/hrtimer.h>
85
86#include <asm/processor.h>
H. J. Lu36d57ac2005-09-06 15:16:49 -070087
Linus Torvalds1da177e2005-04-16 15:20:36 -070088struct exec_domain;
Ingo Molnarc87e2832006-06-27 02:54:58 -070089struct futex_pi_state;
Linus Torvalds1da177e2005-04-16 15:20:36 -070090
91/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070092 * List of flags we want to share for kernel threads,
93 * if only because they are not used by them anyway.
94 */
95#define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
96
97/*
98 * These are the constant used to fake the fixed-point load-average
99 * counting. Some notes:
100 * - 11 bit fractions expand to 22 bits by the multiplies: this gives
101 * a load-average precision of 10 bits integer + 11 bits fractional
102 * - if you want to count load-averages more often, you need more
103 * precision, or rounding will get you. With 2-second counting freq,
104 * the EXP_n values would be 1981, 2034 and 2043 if still using only
105 * 11 bit fractions.
106 */
107extern unsigned long avenrun[]; /* Load averages */
108
109#define FSHIFT 11 /* nr of bits of precision */
110#define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
111#define LOAD_FREQ (5*HZ) /* 5 sec intervals */
112#define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
113#define EXP_5 2014 /* 1/exp(5sec/5min) */
114#define EXP_15 2037 /* 1/exp(5sec/15min) */
115
116#define CALC_LOAD(load,exp,n) \
117 load *= exp; \
118 load += n*(FIXED_1-exp); \
119 load >>= FSHIFT;
120
121extern unsigned long total_forks;
122extern int nr_threads;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123DECLARE_PER_CPU(unsigned long, process_counts);
124extern int nr_processes(void);
125extern unsigned long nr_running(void);
126extern unsigned long nr_uninterruptible(void);
Jack Steinerdb1b1fe2006-03-31 02:31:21 -0800127extern unsigned long nr_active(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128extern unsigned long nr_iowait(void);
Peter Williams2dd73a42006-06-27 02:54:34 -0700129extern unsigned long weighted_cpuload(const int cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131
Linus Torvalds4a8342d2005-09-29 15:18:21 -0700132/*
133 * Task state bitmask. NOTE! These bits are also
134 * encoded in fs/proc/array.c: get_task_state().
135 *
136 * We have two separate sets of flags: task->state
137 * is about runnability, while task->exit_state are
138 * about the task exiting. Confusing, but this way
139 * modifying one set can't modify the other one by
140 * mistake.
141 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142#define TASK_RUNNING 0
143#define TASK_INTERRUPTIBLE 1
144#define TASK_UNINTERRUPTIBLE 2
Linus Torvalds4a8342d2005-09-29 15:18:21 -0700145#define TASK_STOPPED 4
146#define TASK_TRACED 8
147/* in tsk->exit_state */
148#define EXIT_ZOMBIE 16
149#define EXIT_DEAD 32
150/* in tsk->state again */
151#define TASK_NONINTERACTIVE 64
Oleg Nesterovc394cc92006-09-29 02:01:11 -0700152#define TASK_DEAD 128
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153
154#define __set_task_state(tsk, state_value) \
155 do { (tsk)->state = (state_value); } while (0)
156#define set_task_state(tsk, state_value) \
157 set_mb((tsk)->state, (state_value))
158
Andrew Morton498d0c52005-09-13 01:25:14 -0700159/*
160 * set_current_state() includes a barrier so that the write of current->state
161 * is correctly serialised wrt the caller's subsequent test of whether to
162 * actually sleep:
163 *
164 * set_current_state(TASK_UNINTERRUPTIBLE);
165 * if (do_i_need_to_sleep())
166 * schedule();
167 *
168 * If the caller does not need such serialisation then use __set_current_state()
169 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170#define __set_current_state(state_value) \
171 do { current->state = (state_value); } while (0)
172#define set_current_state(state_value) \
173 set_mb(current->state, (state_value))
174
175/* Task command name length */
176#define TASK_COMM_LEN 16
177
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178#include <linux/spinlock.h>
179
180/*
181 * This serializes "schedule()" and also protects
182 * the run-queue from deletions/modifications (but
183 * _adding_ to the beginning of the run-queue has
184 * a separate lock).
185 */
186extern rwlock_t tasklist_lock;
187extern spinlock_t mmlist_lock;
188
Ingo Molnar36c8b582006-07-03 00:25:41 -0700189struct task_struct;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190
191extern void sched_init(void);
192extern void sched_init_smp(void);
Ingo Molnar36c8b582006-07-03 00:25:41 -0700193extern void init_idle(struct task_struct *idle, int cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194
195extern cpumask_t nohz_cpu_mask;
196
197extern void show_state(void);
198extern void show_regs(struct pt_regs *);
199
200/*
201 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
202 * task), SP is the stack pointer of the first frame that should be shown in the back
203 * trace (or NULL if the entire call-chain of the task should be shown).
204 */
205extern void show_stack(struct task_struct *task, unsigned long *sp);
206
207void io_schedule(void);
208long io_schedule_timeout(long timeout);
209
210extern void cpu_init (void);
211extern void trap_init(void);
212extern void update_process_times(int user);
213extern void scheduler_tick(void);
214
Ingo Molnar8446f1d2005-09-06 15:16:27 -0700215#ifdef CONFIG_DETECT_SOFTLOCKUP
Ingo Molnar6687a972006-03-24 03:18:41 -0800216extern void softlockup_tick(void);
Ingo Molnar8446f1d2005-09-06 15:16:27 -0700217extern void spawn_softlockup_task(void);
218extern void touch_softlockup_watchdog(void);
219#else
Ingo Molnar6687a972006-03-24 03:18:41 -0800220static inline void softlockup_tick(void)
Ingo Molnar8446f1d2005-09-06 15:16:27 -0700221{
222}
223static inline void spawn_softlockup_task(void)
224{
225}
226static inline void touch_softlockup_watchdog(void)
227{
228}
229#endif
230
231
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232/* Attach to any functions which should be ignored in wchan output. */
233#define __sched __attribute__((__section__(".sched.text")))
234/* Is this address in the __sched functions? */
235extern int in_sched_functions(unsigned long addr);
236
237#define MAX_SCHEDULE_TIMEOUT LONG_MAX
238extern signed long FASTCALL(schedule_timeout(signed long timeout));
Nishanth Aravamudan64ed93a2005-09-10 00:27:21 -0700239extern signed long schedule_timeout_interruptible(signed long timeout);
240extern signed long schedule_timeout_uninterruptible(signed long timeout);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241asmlinkage void schedule(void);
242
Serge E. Hallynab516012006-10-02 02:18:06 -0700243struct nsproxy;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244
245/* Maximum number of active map areas.. This is a random (large) number */
246#define DEFAULT_MAX_MAP_COUNT 65536
247
248extern int sysctl_max_map_count;
249
250#include <linux/aio.h>
251
252extern unsigned long
253arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
254 unsigned long, unsigned long);
255extern unsigned long
256arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
257 unsigned long len, unsigned long pgoff,
258 unsigned long flags);
Wolfgang Wander1363c3c2005-06-21 17:14:49 -0700259extern void arch_unmap_area(struct mm_struct *, unsigned long);
260extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700262#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
263/*
264 * The mm counters are not protected by its page_table_lock,
265 * so must be incremented atomically.
266 */
Christoph Lameterd3cb4872006-01-06 00:11:20 -0800267#define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
268#define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
269#define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
270#define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
271#define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
272typedef atomic_long_t mm_counter_t;
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700273
274#else /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
275/*
276 * The mm counters are protected by its page_table_lock,
277 * so can be incremented directly.
278 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279#define set_mm_counter(mm, member, value) (mm)->_##member = (value)
280#define get_mm_counter(mm, member) ((mm)->_##member)
281#define add_mm_counter(mm, member, value) (mm)->_##member += (value)
282#define inc_mm_counter(mm, member) (mm)->_##member++
283#define dec_mm_counter(mm, member) (mm)->_##member--
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700284typedef unsigned long mm_counter_t;
Hugh Dickins42946212005-10-29 18:16:05 -0700285
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700286#endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
287
288#define get_mm_rss(mm) \
289 (get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
Hugh Dickins365e9c872005-10-29 18:16:18 -0700290#define update_hiwater_rss(mm) do { \
291 unsigned long _rss = get_mm_rss(mm); \
292 if ((mm)->hiwater_rss < _rss) \
293 (mm)->hiwater_rss = _rss; \
294} while (0)
295#define update_hiwater_vm(mm) do { \
296 if ((mm)->hiwater_vm < (mm)->total_vm) \
297 (mm)->hiwater_vm = (mm)->total_vm; \
298} while (0)
299
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300struct mm_struct {
301 struct vm_area_struct * mmap; /* list of VMAs */
302 struct rb_root mm_rb;
303 struct vm_area_struct * mmap_cache; /* last find_vma result */
304 unsigned long (*get_unmapped_area) (struct file *filp,
305 unsigned long addr, unsigned long len,
306 unsigned long pgoff, unsigned long flags);
Wolfgang Wander1363c3c2005-06-21 17:14:49 -0700307 void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
Benjamin Herrenschmidt0551fbd2006-02-28 16:59:19 -0800308 unsigned long mmap_base; /* base of mmap area */
309 unsigned long task_size; /* size of task vm space */
310 unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */
Wolfgang Wander1363c3c2005-06-21 17:14:49 -0700311 unsigned long free_area_cache; /* first hole of size cached_hole_size or larger */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312 pgd_t * pgd;
313 atomic_t mm_users; /* How many users with user space? */
314 atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */
315 int map_count; /* number of VMAs */
316 struct rw_semaphore mmap_sem;
317 spinlock_t page_table_lock; /* Protects page tables and some counters */
318
319 struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung
320 * together off init_mm.mmlist, and are protected
321 * by mmlist_lock
322 */
323
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700324 /* Special counters, in some configurations protected by the
325 * page_table_lock, in other configurations by being atomic.
326 */
Hugh Dickins42946212005-10-29 18:16:05 -0700327 mm_counter_t _file_rss;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 mm_counter_t _anon_rss;
329
Hugh Dickinsf4499522005-10-29 18:16:19 -0700330 unsigned long hiwater_rss; /* High-watermark of RSS usage */
331 unsigned long hiwater_vm; /* High-water virtual memory usage */
332
333 unsigned long total_vm, locked_vm, shared_vm, exec_vm;
334 unsigned long stack_vm, reserved_vm, def_flags, nr_ptes;
335 unsigned long start_code, end_code, start_data, end_data;
336 unsigned long start_brk, brk, start_stack;
337 unsigned long arg_start, arg_end, env_start, env_end;
338
H. J. Lu36d57ac2005-09-06 15:16:49 -0700339 unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340
Alan Coxd6e71142005-06-23 00:09:43 -0700341 unsigned dumpable:2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342 cpumask_t cpu_vm_mask;
343
344 /* Architecture-specific MM context */
345 mm_context_t context;
346
347 /* Token based thrashing protection. */
348 unsigned long swap_token_time;
349 char recent_pagein;
350
351 /* coredumping support */
352 int core_waiters;
353 struct completion *core_startup_done, core_done;
354
355 /* aio bits */
356 rwlock_t ioctx_list_lock;
357 struct kioctx *ioctx_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358};
359
360struct sighand_struct {
361 atomic_t count;
362 struct k_sigaction action[_NSIG];
363 spinlock_t siglock;
364};
365
KaiGai Kohei0e464812006-06-25 05:49:24 -0700366struct pacct_struct {
KaiGai Koheif6ec29a2006-06-25 05:49:25 -0700367 int ac_flag;
368 long ac_exitcode;
KaiGai Kohei0e464812006-06-25 05:49:24 -0700369 unsigned long ac_mem;
KaiGai Kohei77787bf2006-06-25 05:49:26 -0700370 cputime_t ac_utime, ac_stime;
371 unsigned long ac_minflt, ac_majflt;
KaiGai Kohei0e464812006-06-25 05:49:24 -0700372};
373
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374/*
375 * NOTE! "signal_struct" does not have it's own
376 * locking, because a shared signal_struct always
377 * implies a shared sighand_struct, so locking
378 * sighand_struct is always a proper superset of
379 * the locking of signal_struct.
380 */
381struct signal_struct {
382 atomic_t count;
383 atomic_t live;
384
385 wait_queue_head_t wait_chldexit; /* for wait4() */
386
387 /* current thread group signal load-balancing target: */
Ingo Molnar36c8b582006-07-03 00:25:41 -0700388 struct task_struct *curr_target;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389
390 /* shared signal handling: */
391 struct sigpending shared_pending;
392
393 /* thread group exit support */
394 int group_exit_code;
395 /* overloaded:
396 * - notify group_exit_task when ->count is equal to notify_count
397 * - everyone except group_exit_task is stopped during signal delivery
398 * of fatal signals, group_exit_task processes the signal.
399 */
400 struct task_struct *group_exit_task;
401 int notify_count;
402
403 /* thread group stop support, overloads group_exit_code too */
404 int group_stop_count;
405 unsigned int flags; /* see SIGNAL_* flags below */
406
407 /* POSIX.1b Interval Timers */
408 struct list_head posix_timers;
409
410 /* ITIMER_REAL timer for the process */
Thomas Gleixner2ff678b2006-01-09 20:52:34 -0800411 struct hrtimer real_timer;
Roman Zippel05cfb612006-03-26 01:38:12 -0800412 struct task_struct *tsk;
Thomas Gleixner2ff678b2006-01-09 20:52:34 -0800413 ktime_t it_real_incr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414
415 /* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
416 cputime_t it_prof_expires, it_virt_expires;
417 cputime_t it_prof_incr, it_virt_incr;
418
419 /* job control IDs */
420 pid_t pgrp;
421 pid_t tty_old_pgrp;
422 pid_t session;
423 /* boolean value for session group leader */
424 int leader;
425
426 struct tty_struct *tty; /* NULL if no tty */
427
428 /*
429 * Cumulative resource counters for dead threads in the group,
430 * and for reaped dead child processes forked by this group.
431 * Live threads maintain their own counters and add to these
432 * in __exit_signal, except for the group leader.
433 */
434 cputime_t utime, stime, cutime, cstime;
435 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
436 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
437
438 /*
439 * Cumulative ns of scheduled CPU time for dead threads in the
440 * group, not including a zombie group leader. (This only differs
441 * from jiffies_to_ns(utime + stime) if sched_clock uses something
442 * other than jiffies.)
443 */
444 unsigned long long sched_time;
445
446 /*
447 * We don't bother to synchronize most readers of this at all,
448 * because there is no reader checking a limit that actually needs
449 * to get both rlim_cur and rlim_max atomically, and either one
450 * alone is a single word that can safely be read normally.
451 * getrlimit/setrlimit use task_lock(current->group_leader) to
452 * protect this instead of the siglock, because they really
453 * have no need to disable irqs.
454 */
455 struct rlimit rlim[RLIM_NLIMITS];
456
457 struct list_head cpu_timers[3];
458
459 /* keep the process-shared keyrings here so that they do the right
460 * thing in threads created with CLONE_THREAD */
461#ifdef CONFIG_KEYS
462 struct key *session_keyring; /* keyring inherited over fork */
463 struct key *process_keyring; /* keyring private to this process */
464#endif
KaiGai Kohei0e464812006-06-25 05:49:24 -0700465#ifdef CONFIG_BSD_PROCESS_ACCT
466 struct pacct_struct pacct; /* per-process accounting information */
467#endif
Shailabh Nagarad4ecbc2006-07-14 00:24:44 -0700468#ifdef CONFIG_TASKSTATS
Shailabh Nagarad4ecbc2006-07-14 00:24:44 -0700469 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 Nesterov57a6f512006-09-29 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 */
Siddha, Suresh B89c47102006-10-03 01:14:09 -0700627#define SD_SHARE_PKG_RESOURCES 512 /* Domain members share cpu pkg resources */
Siddha, Suresh B5c45bf22006-06-27 02:54:42 -0700628
Siddha, Suresh B89c47102006-10-03 01:14:09 -0700629#define BALANCE_FOR_MC_POWER \
630 (sched_smt_power_savings ? SD_POWERSAVINGS_BALANCE : 0)
631
632#define BALANCE_FOR_PKG_POWER \
633 ((sched_mc_power_savings || sched_smt_power_savings) ? \
634 SD_POWERSAVINGS_BALANCE : 0)
635
636#define test_sd_parent(sd, flag) ((sd->parent && \
637 (sd->parent->flags & flag)) ? 1 : 0)
Siddha, Suresh B5c45bf22006-06-27 02:54:42 -0700638
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639
640struct sched_group {
641 struct sched_group *next; /* Must be a circular list */
642 cpumask_t cpumask;
643
644 /*
645 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
646 * single CPU. This is read only (except for setup, hotplug CPU).
647 */
648 unsigned long cpu_power;
649};
650
651struct sched_domain {
652 /* These fields must be setup */
653 struct sched_domain *parent; /* top domain must be null terminated */
Siddha, Suresh B1a848872006-10-03 01:14:08 -0700654 struct sched_domain *child; /* bottom domain must be null terminated */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700655 struct sched_group *groups; /* the balancing groups of the domain */
656 cpumask_t span; /* span of all CPUs in this domain */
657 unsigned long min_interval; /* Minimum balance interval ms */
658 unsigned long max_interval; /* Maximum balance interval ms */
659 unsigned int busy_factor; /* less balancing by factor if busy */
660 unsigned int imbalance_pct; /* No balance until over watermark */
661 unsigned long long cache_hot_time; /* Task considered cache hot (ns) */
662 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */
663 unsigned int per_cpu_gain; /* CPU % gained by adding domain cpus */
Nick Piggin78979862005-06-25 14:57:13 -0700664 unsigned int busy_idx;
665 unsigned int idle_idx;
666 unsigned int newidle_idx;
667 unsigned int wake_idx;
Nick Piggin147cbb42005-06-25 14:57:19 -0700668 unsigned int forkexec_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669 int flags; /* See SD_* */
670
671 /* Runtime fields. */
672 unsigned long last_balance; /* init to jiffies. units in jiffies */
673 unsigned int balance_interval; /* initialise to 1. units in ms. */
674 unsigned int nr_balance_failed; /* initialise to 0 */
675
676#ifdef CONFIG_SCHEDSTATS
677 /* load_balance() stats */
678 unsigned long lb_cnt[MAX_IDLE_TYPES];
679 unsigned long lb_failed[MAX_IDLE_TYPES];
680 unsigned long lb_balanced[MAX_IDLE_TYPES];
681 unsigned long lb_imbalance[MAX_IDLE_TYPES];
682 unsigned long lb_gained[MAX_IDLE_TYPES];
683 unsigned long lb_hot_gained[MAX_IDLE_TYPES];
684 unsigned long lb_nobusyg[MAX_IDLE_TYPES];
685 unsigned long lb_nobusyq[MAX_IDLE_TYPES];
686
687 /* Active load balancing */
688 unsigned long alb_cnt;
689 unsigned long alb_failed;
690 unsigned long alb_pushed;
691
Nick Piggin68767a02005-06-25 14:57:20 -0700692 /* SD_BALANCE_EXEC stats */
693 unsigned long sbe_cnt;
694 unsigned long sbe_balanced;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700695 unsigned long sbe_pushed;
696
Nick Piggin68767a02005-06-25 14:57:20 -0700697 /* SD_BALANCE_FORK stats */
698 unsigned long sbf_cnt;
699 unsigned long sbf_balanced;
700 unsigned long sbf_pushed;
701
Linus Torvalds1da177e2005-04-16 15:20:36 -0700702 /* try_to_wake_up() stats */
703 unsigned long ttwu_wake_remote;
704 unsigned long ttwu_move_affine;
705 unsigned long ttwu_move_balance;
706#endif
707};
708
Srivatsa Vaddagiri51888ca2006-06-27 02:54:38 -0700709extern int partition_sched_domains(cpumask_t *partition1,
Dinakar Guniguntala1a20ff22005-06-25 14:57:33 -0700710 cpumask_t *partition2);
akpm@osdl.org198e2f12006-01-12 01:05:30 -0800711
712/*
713 * Maximum cache size the migration-costs auto-tuning code will
714 * search from:
715 */
716extern unsigned int max_cache_size;
717
718#endif /* CONFIG_SMP */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700719
720
721struct io_context; /* See blkdev.h */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722struct cpuset;
723
724#define NGROUPS_SMALL 32
725#define NGROUPS_PER_BLOCK ((int)(PAGE_SIZE / sizeof(gid_t)))
726struct group_info {
727 int ngroups;
728 atomic_t usage;
729 gid_t small_block[NGROUPS_SMALL];
730 int nblocks;
731 gid_t *blocks[0];
732};
733
734/*
735 * get_group_info() must be called with the owning task locked (via task_lock())
736 * when task != current. The reason being that the vast majority of callers are
737 * looking at current->group_info, which can not be changed except by the
738 * current task. Changing current->group_info requires the task lock, too.
739 */
740#define get_group_info(group_info) do { \
741 atomic_inc(&(group_info)->usage); \
742} while (0)
743
744#define put_group_info(group_info) do { \
745 if (atomic_dec_and_test(&(group_info)->usage)) \
746 groups_free(group_info); \
747} while (0)
748
David Howells3e301482005-06-23 22:00:56 -0700749extern struct group_info *groups_alloc(int gidsetsize);
750extern void groups_free(struct group_info *group_info);
751extern int set_current_groups(struct group_info *group_info);
752extern int groups_search(struct group_info *group_info, gid_t grp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753/* access the groups "array" with this macro */
754#define GROUP_AT(gi, i) \
755 ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
756
Chen, Kenneth W383f2832005-09-09 13:02:02 -0700757#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
Ingo Molnar36c8b582006-07-03 00:25:41 -0700758extern void prefetch_stack(struct task_struct *t);
Chen, Kenneth W383f2832005-09-09 13:02:02 -0700759#else
760static inline void prefetch_stack(struct task_struct *t) { }
761#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762
763struct audit_context; /* See audit.c */
764struct mempolicy;
Jens Axboeb92ce552006-04-11 13:52:07 +0200765struct pipe_inode_info;
Serge E. Hallyn4865ecf2006-10-02 02:18:14 -0700766struct uts_namespace;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767
Con Kolivas3dee3862006-03-31 02:31:23 -0800768enum sleep_type {
769 SLEEP_NORMAL,
770 SLEEP_NONINTERACTIVE,
771 SLEEP_INTERACTIVE,
772 SLEEP_INTERRUPTED,
773};
774
Ingo Molnar70b97a72006-07-03 00:25:42 -0700775struct prio_array;
776
Linus Torvalds1da177e2005-04-16 15:20:36 -0700777struct task_struct {
778 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
779 struct thread_info *thread_info;
780 atomic_t usage;
781 unsigned long flags; /* per process flags, defined below */
782 unsigned long ptrace;
783
Paolo 'Blaisorblade' Giarrusso36772092005-05-05 16:16:12 -0700784 int lock_depth; /* BKL lock depth */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785
Peter Williams2dd73a42006-06-27 02:54:34 -0700786#ifdef CONFIG_SMP
787#ifdef __ARCH_WANT_UNLOCKED_CTXSW
Nick Piggin4866cde2005-06-25 14:57:23 -0700788 int oncpu;
789#endif
Peter Williams2dd73a42006-06-27 02:54:34 -0700790#endif
791 int load_weight; /* for niceness load balancing purposes */
Ingo Molnarb29739f2006-06-27 02:54:51 -0700792 int prio, static_prio, normal_prio;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700793 struct list_head run_list;
Ingo Molnar70b97a72006-07-03 00:25:42 -0700794 struct prio_array *array;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700795
Jens Axboe22e2c502005-06-27 10:55:12 +0200796 unsigned short ioprio;
Alexey Dobriyan6c5c9342006-09-29 01:59:40 -0700797#ifdef CONFIG_BLK_DEV_IO_TRACE
Jens Axboe2056a782006-03-23 20:00:26 +0100798 unsigned int btrace_seq;
Alexey Dobriyan6c5c9342006-09-29 01:59:40 -0700799#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800 unsigned long sleep_avg;
801 unsigned long long timestamp, last_ran;
802 unsigned long long sched_time; /* sched_clock time spent running */
Con Kolivas3dee3862006-03-31 02:31:23 -0800803 enum sleep_type sleep_type;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804
805 unsigned long policy;
806 cpumask_t cpus_allowed;
807 unsigned int time_slice, first_time_slice;
808
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700809#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810 struct sched_info sched_info;
811#endif
812
813 struct list_head tasks;
814 /*
815 * ptrace_list/ptrace_children forms the list of my children
816 * that were stolen by a ptracer.
817 */
818 struct list_head ptrace_children;
819 struct list_head ptrace_list;
820
821 struct mm_struct *mm, *active_mm;
822
823/* task state */
824 struct linux_binfmt *binfmt;
825 long exit_state;
826 int exit_code, exit_signal;
827 int pdeath_signal; /* The signal sent when the parent dies */
828 /* ??? */
829 unsigned long personality;
830 unsigned did_exec:1;
831 pid_t pid;
832 pid_t tgid;
Arjan van de Ven0a425402006-09-26 10:52:38 +0200833
834#ifdef CONFIG_CC_STACKPROTECTOR
835 /* Canary value for the -fstack-protector gcc feature */
836 unsigned long stack_canary;
837#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838 /*
839 * pointers to (original) parent process, youngest child, younger sibling,
840 * older sibling, respectively. (p->father can be replaced with
841 * p->parent->pid)
842 */
843 struct task_struct *real_parent; /* real parent process (when being debugged) */
844 struct task_struct *parent; /* parent process */
845 /*
846 * children/sibling forms the list of my children plus the
847 * tasks I'm ptracing.
848 */
849 struct list_head children; /* list of my children */
850 struct list_head sibling; /* linkage in my parent's children list */
851 struct task_struct *group_leader; /* threadgroup leader */
852
853 /* PID/PID hash table linkage. */
Eric W. Biederman92476d72006-03-31 02:31:42 -0800854 struct pid_link pids[PIDTYPE_MAX];
Oleg Nesterov47e65322006-03-28 16:11:25 -0800855 struct list_head thread_group;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700856
857 struct completion *vfork_done; /* for vfork() */
858 int __user *set_child_tid; /* CLONE_CHILD_SETTID */
859 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
860
861 unsigned long rt_priority;
862 cputime_t utime, stime;
863 unsigned long nvcsw, nivcsw; /* context switch counts */
864 struct timespec start_time;
865/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
866 unsigned long min_flt, maj_flt;
867
868 cputime_t it_prof_expires, it_virt_expires;
869 unsigned long long it_sched_expires;
870 struct list_head cpu_timers[3];
871
872/* process credentials */
873 uid_t uid,euid,suid,fsuid;
874 gid_t gid,egid,sgid,fsgid;
875 struct group_info *group_info;
876 kernel_cap_t cap_effective, cap_inheritable, cap_permitted;
877 unsigned keep_capabilities:1;
878 struct user_struct *user;
879#ifdef CONFIG_KEYS
David Howellsb5f545c2006-01-08 01:02:47 -0800880 struct key *request_key_auth; /* assumed request_key authority */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700881 struct key *thread_keyring; /* keyring private to this thread */
David Howells3e301482005-06-23 22:00:56 -0700882 unsigned char jit_keyring; /* default keyring to attach requested keys to */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700883#endif
Arjan van de Vene07e23e2006-09-26 10:52:36 +0200884 /*
885 * fpu_counter contains the number of consecutive context switches
886 * that the FPU is used. If this is over a threshold, the lazy fpu
887 * saving becomes unlazy to save the trap. This is an unsigned char
888 * so that after 256 times the counter wraps and the behavior turns
889 * lazy again; this to deal with bursty apps that only use FPU for
890 * a short time
891 */
892 unsigned char fpu_counter;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700893 int oomkilladj; /* OOM kill score adjustment (bit shift). */
Paolo 'Blaisorblade' Giarrusso36772092005-05-05 16:16:12 -0700894 char comm[TASK_COMM_LEN]; /* executable name excluding path
895 - access with [gs]et_task_comm (which lock
896 it with task_lock())
897 - initialized normally by flush_old_exec */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700898/* file system info */
899 int link_count, total_link_count;
Alexey Dobriyan3d5b6fc2006-09-29 01:59:40 -0700900#ifdef CONFIG_SYSVIPC
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901/* ipc stuff */
902 struct sysv_sem sysvsem;
Alexey Dobriyan3d5b6fc2006-09-29 01:59:40 -0700903#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700904/* CPU-specific state of this task */
905 struct thread_struct thread;
906/* filesystem information */
907 struct fs_struct *fs;
908/* open file information */
909 struct files_struct *files;
Serge E. Hallyn1651e142006-10-02 02:18:08 -0700910/* namespaces */
Serge E. Hallynab516012006-10-02 02:18:06 -0700911 struct nsproxy *nsproxy;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700912/* signal handlers */
913 struct signal_struct *signal;
914 struct sighand_struct *sighand;
915
916 sigset_t blocked, real_blocked;
David Woodhouse150256d2006-01-18 17:43:57 -0800917 sigset_t saved_sigmask; /* To be restored with TIF_RESTORE_SIGMASK */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700918 struct sigpending pending;
919
920 unsigned long sas_ss_sp;
921 size_t sas_ss_size;
922 int (*notifier)(void *priv);
923 void *notifier_data;
924 sigset_t *notifier_mask;
925
926 void *security;
927 struct audit_context *audit_context;
928 seccomp_t seccomp;
929
930/* Thread group tracking */
931 u32 parent_exec_id;
932 u32 self_exec_id;
933/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
934 spinlock_t alloc_lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700935
Ingo Molnarb29739f2006-06-27 02:54:51 -0700936 /* Protection of the PI data structures: */
937 spinlock_t pi_lock;
938
Ingo Molnar23f78d4a2006-06-27 02:54:53 -0700939#ifdef CONFIG_RT_MUTEXES
940 /* PI waiters blocked on a rt_mutex held by this task */
941 struct plist_head pi_waiters;
942 /* Deadlock detection and priority inheritance handling */
943 struct rt_mutex_waiter *pi_blocked_on;
Ingo Molnar23f78d4a2006-06-27 02:54:53 -0700944#endif
945
Ingo Molnar408894e2006-01-09 15:59:20 -0800946#ifdef CONFIG_DEBUG_MUTEXES
947 /* mutex deadlock detection */
948 struct mutex_waiter *blocked_on;
949#endif
Ingo Molnarde30a2b2006-07-03 00:24:42 -0700950#ifdef CONFIG_TRACE_IRQFLAGS
951 unsigned int irq_events;
952 int hardirqs_enabled;
953 unsigned long hardirq_enable_ip;
954 unsigned int hardirq_enable_event;
955 unsigned long hardirq_disable_ip;
956 unsigned int hardirq_disable_event;
957 int softirqs_enabled;
958 unsigned long softirq_disable_ip;
959 unsigned int softirq_disable_event;
960 unsigned long softirq_enable_ip;
961 unsigned int softirq_enable_event;
962 int hardirq_context;
963 int softirq_context;
964#endif
Ingo Molnarfbb9ce952006-07-03 00:24:50 -0700965#ifdef CONFIG_LOCKDEP
966# define MAX_LOCK_DEPTH 30UL
967 u64 curr_chain_key;
968 int lockdep_depth;
969 struct held_lock held_locks[MAX_LOCK_DEPTH];
970 unsigned int lockdep_recursion;
971#endif
Ingo Molnar408894e2006-01-09 15:59:20 -0800972
Linus Torvalds1da177e2005-04-16 15:20:36 -0700973/* journalling filesystem info */
974 void *journal_info;
975
976/* VM state */
977 struct reclaim_state *reclaim_state;
978
Linus Torvalds1da177e2005-04-16 15:20:36 -0700979 struct backing_dev_info *backing_dev_info;
980
981 struct io_context *io_context;
982
983 unsigned long ptrace_message;
984 siginfo_t *last_siginfo; /* For ptrace use. */
985/*
986 * current io wait handle: wait queue entry to use for io waits
987 * If this thread is processing aio, this points at the waitqueue
988 * inside the currently handled kiocb. It may be NULL (i.e. default
989 * to a stack based synchronous wait) if its doing sync IO.
990 */
991 wait_queue_t *io_wait;
992/* i/o counters(bytes read/written, #syscalls */
993 u64 rchar, wchar, syscr, syscw;
Jay Lan8f0ab512006-09-30 23:28:59 -0700994#if defined(CONFIG_TASK_XACCT)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700995 u64 acct_rss_mem1; /* accumulated rss usage */
996 u64 acct_vm_mem1; /* accumulated virtual memory usage */
Jay Landb5fed262006-09-30 23:29:00 -0700997 cputime_t acct_stimexpd;/* stime since last update */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700998#endif
999#ifdef CONFIG_NUMA
1000 struct mempolicy *mempolicy;
1001 short il_next;
1002#endif
1003#ifdef CONFIG_CPUSETS
1004 struct cpuset *cpuset;
1005 nodemask_t mems_allowed;
1006 int cpuset_mems_generation;
Paul Jackson825a46a2006-03-24 03:16:03 -08001007 int cpuset_mem_spread_rotor;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001008#endif
Ingo Molnar0771dfe2006-03-27 01:16:22 -08001009 struct robust_list_head __user *robust_list;
Ingo Molnar34f192c2006-03-27 01:16:24 -08001010#ifdef CONFIG_COMPAT
1011 struct compat_robust_list_head __user *compat_robust_list;
1012#endif
Ingo Molnarc87e2832006-06-27 02:54:58 -07001013 struct list_head pi_state_list;
1014 struct futex_pi_state *pi_state_cache;
Ingo Molnar0771dfe2006-03-27 01:16:22 -08001015
Jens Axboe22e2c502005-06-27 10:55:12 +02001016 atomic_t fs_excl; /* holding fs exclusive resources */
Ingo Molnare56d0902006-01-08 01:01:37 -08001017 struct rcu_head rcu;
Jens Axboeb92ce552006-04-11 13:52:07 +02001018
1019 /*
1020 * cache last used pipe for splice
1021 */
1022 struct pipe_inode_info *splice_pipe;
Shailabh Nagarca74e922006-07-14 00:24:36 -07001023#ifdef CONFIG_TASK_DELAY_ACCT
1024 struct task_delay_info *delays;
1025#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001026};
1027
1028static inline pid_t process_group(struct task_struct *tsk)
1029{
1030 return tsk->signal->pgrp;
1031}
1032
Eric W. Biederman22c935f2006-10-02 02:17:09 -07001033static inline struct pid *task_pid(struct task_struct *task)
1034{
1035 return task->pids[PIDTYPE_PID].pid;
1036}
1037
1038static inline struct pid *task_tgid(struct task_struct *task)
1039{
1040 return task->group_leader->pids[PIDTYPE_PID].pid;
1041}
1042
1043static inline struct pid *task_pgrp(struct task_struct *task)
1044{
1045 return task->group_leader->pids[PIDTYPE_PGID].pid;
1046}
1047
1048static inline struct pid *task_session(struct task_struct *task)
1049{
1050 return task->group_leader->pids[PIDTYPE_SID].pid;
1051}
1052
Linus Torvalds1da177e2005-04-16 15:20:36 -07001053/**
1054 * pid_alive - check that a task structure is not stale
1055 * @p: Task structure to be checked.
1056 *
1057 * Test if a process is not yet dead (at most zombie state)
1058 * If pid_alive fails, then pointers within the task structure
1059 * can be stale and must not be dereferenced.
1060 */
1061static inline int pid_alive(struct task_struct *p)
1062{
Eric W. Biederman92476d72006-03-31 02:31:42 -08001063 return p->pids[PIDTYPE_PID].pid != NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001064}
1065
Sukadev Bhattiproluf400e192006-09-29 02:00:07 -07001066/**
Henne32602592006-10-06 00:44:01 -07001067 * is_init - check if a task structure is init
1068 * @tsk: Task structure to be checked.
1069 *
1070 * Check if a task structure is the first user space task the kernel created.
Sukadev Bhattiproluf400e192006-09-29 02:00:07 -07001071 */
1072static inline int is_init(struct task_struct *tsk)
1073{
1074 return tsk->pid == 1;
1075}
1076
Cedric Le Goater9ec52092006-10-02 02:19:00 -07001077extern struct pid *cad_pid;
1078
Linus Torvalds1da177e2005-04-16 15:20:36 -07001079extern void free_task(struct task_struct *tsk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001080#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
Ingo Molnare56d0902006-01-08 01:01:37 -08001081
Andrew Morton158d9eb2006-03-31 02:31:34 -08001082extern void __put_task_struct(struct task_struct *t);
Ingo Molnare56d0902006-01-08 01:01:37 -08001083
1084static inline void put_task_struct(struct task_struct *t)
1085{
1086 if (atomic_dec_and_test(&t->usage))
Eric W. Biederman8c7904a2006-03-31 02:31:37 -08001087 __put_task_struct(t);
Ingo Molnare56d0902006-01-08 01:01:37 -08001088}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001089
1090/*
1091 * Per process flags
1092 */
1093#define PF_ALIGNWARN 0x00000001 /* Print alignment warning msgs */
1094 /* Not implemented yet, only for 486*/
1095#define PF_STARTING 0x00000002 /* being created */
1096#define PF_EXITING 0x00000004 /* getting shut down */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001097#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
1098#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
1099#define PF_DUMPCORE 0x00000200 /* dumped core */
1100#define PF_SIGNALED 0x00000400 /* killed by a signal */
1101#define PF_MEMALLOC 0x00000800 /* Allocating memory */
1102#define PF_FLUSHER 0x00001000 /* responsible for disk writeback */
1103#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
1104#define PF_FREEZE 0x00004000 /* this task is being frozen for suspend now */
1105#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
1106#define PF_FROZEN 0x00010000 /* frozen for system suspend */
1107#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
1108#define PF_KSWAPD 0x00040000 /* I am kswapd */
1109#define PF_SWAPOFF 0x00080000 /* I am in swapoff */
1110#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
Jens Axboeb31dc662006-06-13 08:26:10 +02001111#define PF_BORROWED_MM 0x00200000 /* I am a kthread doing use_mm */
1112#define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */
1113#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1114#define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */
1115#define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */
Paul Jacksonc61afb12006-03-24 03:16:08 -08001116#define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */
Thomas Gleixner61a87122006-06-27 02:54:56 -07001117#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001118
1119/*
1120 * Only the _current_ task can read/write to tsk->flags, but other
1121 * tasks can access tsk->flags in readonly mode for example
1122 * with tsk_used_math (like during threaded core dumping).
1123 * There is however an exception to this rule during ptrace
1124 * or during fork: the ptracer task is allowed to write to the
1125 * child->flags of its traced child (same goes for fork, the parent
1126 * can write to the child->flags), because we're guaranteed the
1127 * child is not running and in turn not changing child->flags
1128 * at the same time the parent does it.
1129 */
1130#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1131#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1132#define clear_used_math() clear_stopped_child_used_math(current)
1133#define set_used_math() set_stopped_child_used_math(current)
1134#define conditional_stopped_child_used_math(condition, child) \
1135 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1136#define conditional_used_math(condition) \
1137 conditional_stopped_child_used_math(condition, current)
1138#define copy_to_stopped_child_used_math(child) \
1139 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1140/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1141#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1142#define used_math() tsk_used_math(current)
1143
1144#ifdef CONFIG_SMP
Ingo Molnar36c8b582006-07-03 00:25:41 -07001145extern int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001146#else
Ingo Molnar36c8b582006-07-03 00:25:41 -07001147static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148{
Paul Jackson4098f992005-10-30 15:03:21 -08001149 if (!cpu_isset(0, new_mask))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001150 return -EINVAL;
1151 return 0;
1152}
1153#endif
1154
1155extern unsigned long long sched_clock(void);
Ingo Molnar36c8b582006-07-03 00:25:41 -07001156extern unsigned long long
1157current_sched_time(const struct task_struct *current_task);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001158
1159/* sched_exec is called by processes performing an exec */
1160#ifdef CONFIG_SMP
1161extern void sched_exec(void);
1162#else
1163#define sched_exec() {}
1164#endif
1165
1166#ifdef CONFIG_HOTPLUG_CPU
1167extern void idle_task_exit(void);
1168#else
1169static inline void idle_task_exit(void) {}
1170#endif
1171
1172extern void sched_idle_next(void);
Ingo Molnarb29739f2006-06-27 02:54:51 -07001173
1174#ifdef CONFIG_RT_MUTEXES
Ingo Molnar36c8b582006-07-03 00:25:41 -07001175extern int rt_mutex_getprio(struct task_struct *p);
1176extern void rt_mutex_setprio(struct task_struct *p, int prio);
1177extern void rt_mutex_adjust_pi(struct task_struct *p);
Ingo Molnarb29739f2006-06-27 02:54:51 -07001178#else
Ingo Molnar36c8b582006-07-03 00:25:41 -07001179static inline int rt_mutex_getprio(struct task_struct *p)
Ingo Molnarb29739f2006-06-27 02:54:51 -07001180{
1181 return p->normal_prio;
1182}
Thomas Gleixner95e02ca2006-06-27 02:55:02 -07001183# define rt_mutex_adjust_pi(p) do { } while (0)
Ingo Molnarb29739f2006-06-27 02:54:51 -07001184#endif
1185
Ingo Molnar36c8b582006-07-03 00:25:41 -07001186extern void set_user_nice(struct task_struct *p, long nice);
1187extern int task_prio(const struct task_struct *p);
1188extern int task_nice(const struct task_struct *p);
1189extern int can_nice(const struct task_struct *p, const int nice);
1190extern int task_curr(const struct task_struct *p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001191extern int idle_cpu(int cpu);
1192extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
Ingo Molnar36c8b582006-07-03 00:25:41 -07001193extern struct task_struct *idle_task(int cpu);
1194extern struct task_struct *curr_task(int cpu);
1195extern void set_curr_task(int cpu, struct task_struct *p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001196
1197void yield(void);
1198
1199/*
1200 * The default (Linux) execution domain.
1201 */
1202extern struct exec_domain default_exec_domain;
1203
1204union thread_union {
1205 struct thread_info thread_info;
1206 unsigned long stack[THREAD_SIZE/sizeof(long)];
1207};
1208
1209#ifndef __HAVE_ARCH_KSTACK_END
1210static inline int kstack_end(void *addr)
1211{
1212 /* Reliable end of stack detection:
1213 * Some APM bios versions misalign the stack
1214 */
1215 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1216}
1217#endif
1218
1219extern union thread_union init_thread_union;
1220extern struct task_struct init_task;
1221
1222extern struct mm_struct init_mm;
1223
1224#define find_task_by_pid(nr) find_task_by_pid_type(PIDTYPE_PID, nr)
1225extern struct task_struct *find_task_by_pid_type(int type, int pid);
1226extern void set_special_pids(pid_t session, pid_t pgrp);
1227extern void __set_special_pids(pid_t session, pid_t pgrp);
1228
1229/* per-UID process charging. */
1230extern struct user_struct * alloc_uid(uid_t);
1231static inline struct user_struct *get_uid(struct user_struct *u)
1232{
1233 atomic_inc(&u->__count);
1234 return u;
1235}
1236extern void free_uid(struct user_struct *);
1237extern void switch_uid(struct user_struct *);
1238
1239#include <asm/current.h>
1240
Atsushi Nemoto3171a032006-09-29 02:00:32 -07001241extern void do_timer(unsigned long ticks);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001242
1243extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state));
1244extern int FASTCALL(wake_up_process(struct task_struct * tsk));
1245extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
1246 unsigned long clone_flags));
1247#ifdef CONFIG_SMP
1248 extern void kick_process(struct task_struct *tsk);
1249#else
1250 static inline void kick_process(struct task_struct *tsk) { }
1251#endif
Ingo Molnar36c8b582006-07-03 00:25:41 -07001252extern void FASTCALL(sched_fork(struct task_struct * p, int clone_flags));
1253extern void FASTCALL(sched_exit(struct task_struct * p));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001254
1255extern int in_group_p(gid_t);
1256extern int in_egroup_p(gid_t);
1257
1258extern void proc_caches_init(void);
1259extern void flush_signals(struct task_struct *);
1260extern void flush_signal_handlers(struct task_struct *, int force_default);
1261extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1262
1263static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1264{
1265 unsigned long flags;
1266 int ret;
1267
1268 spin_lock_irqsave(&tsk->sighand->siglock, flags);
1269 ret = dequeue_signal(tsk, mask, info);
1270 spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1271
1272 return ret;
1273}
1274
1275extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1276 sigset_t *mask);
1277extern void unblock_all_signals(void);
1278extern void release_task(struct task_struct * p);
1279extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1280extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
1281extern int force_sigsegv(int, struct task_struct *);
1282extern int force_sig_info(int, struct siginfo *, struct task_struct *);
Eric W. Biedermanc4b92fc2006-10-02 02:17:10 -07001283extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1284extern int kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1285extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
Eric W. Biederman2425c082006-10-02 02:17:28 -07001286extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
Eric W. Biedermanc4b92fc2006-10-02 02:17:10 -07001287extern int kill_pgrp(struct pid *pid, int sig, int priv);
1288extern int kill_pid(struct pid *pid, int sig, int priv);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001289extern int __kill_pg_info(int sig, struct siginfo *info, pid_t pgrp);
1290extern int kill_pg_info(int, struct siginfo *, pid_t);
1291extern int kill_proc_info(int, struct siginfo *, pid_t);
1292extern void do_notify_parent(struct task_struct *, int);
1293extern void force_sig(int, struct task_struct *);
1294extern void force_sig_specific(int, struct task_struct *);
1295extern int send_sig(int, struct task_struct *, int);
1296extern void zap_other_threads(struct task_struct *p);
1297extern int kill_pg(pid_t, int, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001298extern int kill_proc(pid_t, int, int);
1299extern struct sigqueue *sigqueue_alloc(void);
1300extern void sigqueue_free(struct sigqueue *);
1301extern int send_sigqueue(int, struct sigqueue *, struct task_struct *);
1302extern int send_group_sigqueue(int, struct sigqueue *, struct task_struct *);
Oleg Nesterov9ac95f22006-02-09 22:41:50 +03001303extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001304extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1305
Cedric Le Goater9ec52092006-10-02 02:19:00 -07001306static inline int kill_cad_pid(int sig, int priv)
1307{
1308 return kill_pid(cad_pid, sig, priv);
1309}
1310
Linus Torvalds1da177e2005-04-16 15:20:36 -07001311/* These can be the second arg to send_sig_info/send_group_sig_info. */
1312#define SEND_SIG_NOINFO ((struct siginfo *) 0)
1313#define SEND_SIG_PRIV ((struct siginfo *) 1)
1314#define SEND_SIG_FORCED ((struct siginfo *) 2)
1315
Oleg Nesterov621d3122005-10-30 15:03:45 -08001316static inline int is_si_special(const struct siginfo *info)
1317{
1318 return info <= SEND_SIG_FORCED;
1319}
1320
Linus Torvalds1da177e2005-04-16 15:20:36 -07001321/* True if we are on the alternate signal stack. */
1322
1323static inline int on_sig_stack(unsigned long sp)
1324{
1325 return (sp - current->sas_ss_sp < current->sas_ss_size);
1326}
1327
1328static inline int sas_ss_flags(unsigned long sp)
1329{
1330 return (current->sas_ss_size == 0 ? SS_DISABLE
1331 : on_sig_stack(sp) ? SS_ONSTACK : 0);
1332}
1333
Linus Torvalds1da177e2005-04-16 15:20:36 -07001334/*
1335 * Routines for handling mm_structs
1336 */
1337extern struct mm_struct * mm_alloc(void);
1338
1339/* mmdrop drops the mm and the page tables */
1340extern void FASTCALL(__mmdrop(struct mm_struct *));
1341static inline void mmdrop(struct mm_struct * mm)
1342{
1343 if (atomic_dec_and_test(&mm->mm_count))
1344 __mmdrop(mm);
1345}
1346
1347/* mmput gets rid of the mappings and all user-space */
1348extern void mmput(struct mm_struct *);
1349/* Grab a reference to a task's mm, if it is not already going away */
1350extern struct mm_struct *get_task_mm(struct task_struct *task);
1351/* Remove the current tasks stale references to the old mm_struct */
1352extern void mm_release(struct task_struct *, struct mm_struct *);
1353
1354extern int copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1355extern void flush_thread(void);
1356extern void exit_thread(void);
1357
Linus Torvalds1da177e2005-04-16 15:20:36 -07001358extern void exit_files(struct task_struct *);
Oleg Nesterov6b3934e2006-03-28 16:11:16 -08001359extern void __cleanup_signal(struct signal_struct *);
Oleg Nesterova7e53282006-03-28 16:11:27 -08001360extern void __cleanup_sighand(struct sighand_struct *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001361extern void exit_itimers(struct signal_struct *);
1362
1363extern NORET_TYPE void do_group_exit(int);
1364
Linus Torvalds1da177e2005-04-16 15:20:36 -07001365extern void daemonize(const char *, ...);
1366extern int allow_signal(int);
1367extern int disallow_signal(int);
Ingo Molnar36c8b582006-07-03 00:25:41 -07001368extern struct task_struct *child_reaper;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001369
1370extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1371extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
Ingo Molnar36c8b582006-07-03 00:25:41 -07001372struct task_struct *fork_idle(int);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001373
1374extern void set_task_comm(struct task_struct *tsk, char *from);
1375extern void get_task_comm(char *to, struct task_struct *tsk);
1376
1377#ifdef CONFIG_SMP
Ingo Molnar36c8b582006-07-03 00:25:41 -07001378extern void wait_task_inactive(struct task_struct * p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001379#else
1380#define wait_task_inactive(p) do { } while (0)
1381#endif
1382
1383#define remove_parent(p) list_del_init(&(p)->sibling)
Oleg Nesterov8fafabd2006-03-28 16:11:05 -08001384#define add_parent(p) list_add_tail(&(p)->sibling,&(p)->parent->children)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001385
Eric W. Biederman5e85d4a2006-04-18 22:20:16 -07001386#define next_task(p) list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001387
1388#define for_each_process(p) \
1389 for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1390
1391/*
1392 * Careful: do_each_thread/while_each_thread is a double loop so
1393 * 'break' will not work as expected - use goto instead.
1394 */
1395#define do_each_thread(g, t) \
1396 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1397
1398#define while_each_thread(g, t) \
1399 while ((t = next_thread(t)) != g)
1400
Eric W. Biedermande12a782006-04-10 17:16:49 -06001401/* de_thread depends on thread_group_leader not being a pid based check */
1402#define thread_group_leader(p) (p == p->group_leader)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001403
Eric W. Biederman0804ef42006-10-02 02:17:04 -07001404/* Do to the insanities of de_thread it is possible for a process
1405 * to have the pid of the thread group leader without actually being
1406 * the thread group leader. For iteration through the pids in proc
1407 * all we care about is that we have a task with the appropriate
1408 * pid, we don't actually care if we have the right task.
1409 */
1410static inline int has_group_leader_pid(struct task_struct *p)
1411{
1412 return p->pid == p->tgid;
1413}
1414
Ingo Molnar36c8b582006-07-03 00:25:41 -07001415static inline struct task_struct *next_thread(const struct task_struct *p)
Oleg Nesterov47e65322006-03-28 16:11:25 -08001416{
1417 return list_entry(rcu_dereference(p->thread_group.next),
Ingo Molnar36c8b582006-07-03 00:25:41 -07001418 struct task_struct, thread_group);
Oleg Nesterov47e65322006-03-28 16:11:25 -08001419}
1420
Ingo Molnar36c8b582006-07-03 00:25:41 -07001421static inline int thread_group_empty(struct task_struct *p)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001422{
Oleg Nesterov47e65322006-03-28 16:11:25 -08001423 return list_empty(&p->thread_group);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001424}
1425
1426#define delay_group_leader(p) \
1427 (thread_group_leader(p) && !thread_group_empty(p))
1428
Linus Torvalds1da177e2005-04-16 15:20:36 -07001429/*
Eric W. Biederman260ea102006-06-23 02:05:18 -07001430 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
Jens Axboe22e2c502005-06-27 10:55:12 +02001431 * subscriptions and synchronises with wait4(). Also used in procfs. Also
Paul Jackson053199e2005-10-30 15:02:30 -08001432 * pins the final release of task.io_context. Also protects ->cpuset.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001433 *
1434 * Nests both inside and outside of read_lock(&tasklist_lock).
1435 * It must not be nested with write_lock_irq(&tasklist_lock),
1436 * neither inside nor outside.
1437 */
1438static inline void task_lock(struct task_struct *p)
1439{
1440 spin_lock(&p->alloc_lock);
1441}
1442
1443static inline void task_unlock(struct task_struct *p)
1444{
1445 spin_unlock(&p->alloc_lock);
1446}
1447
Oleg Nesterovf63ee722006-03-28 16:11:13 -08001448extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
1449 unsigned long *flags);
1450
1451static inline void unlock_task_sighand(struct task_struct *tsk,
1452 unsigned long *flags)
1453{
1454 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
1455}
1456
Al Virof0373602005-11-13 16:06:57 -08001457#ifndef __HAVE_THREAD_FUNCTIONS
1458
Al Viroa1261f52005-11-13 16:06:55 -08001459#define task_thread_info(task) (task)->thread_info
Al Viro9fc65872006-01-12 01:05:34 -08001460#define task_stack_page(task) ((void*)((task)->thread_info))
Al Viroa1261f52005-11-13 16:06:55 -08001461
Al Viro10ebffd2005-11-13 16:06:56 -08001462static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
1463{
1464 *task_thread_info(p) = *task_thread_info(org);
1465 task_thread_info(p)->task = p;
1466}
1467
1468static inline unsigned long *end_of_stack(struct task_struct *p)
1469{
1470 return (unsigned long *)(p->thread_info + 1);
1471}
1472
Al Virof0373602005-11-13 16:06:57 -08001473#endif
1474
Linus Torvalds1da177e2005-04-16 15:20:36 -07001475/* set thread flags in other task's structures
1476 * - see asm/thread_info.h for TIF_xxxx flags available
1477 */
1478static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1479{
Al Viroa1261f52005-11-13 16:06:55 -08001480 set_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001481}
1482
1483static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1484{
Al Viroa1261f52005-11-13 16:06:55 -08001485 clear_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001486}
1487
1488static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1489{
Al Viroa1261f52005-11-13 16:06:55 -08001490 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001491}
1492
1493static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1494{
Al Viroa1261f52005-11-13 16:06:55 -08001495 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001496}
1497
1498static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1499{
Al Viroa1261f52005-11-13 16:06:55 -08001500 return test_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001501}
1502
1503static inline void set_tsk_need_resched(struct task_struct *tsk)
1504{
1505 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1506}
1507
1508static inline void clear_tsk_need_resched(struct task_struct *tsk)
1509{
1510 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1511}
1512
1513static inline int signal_pending(struct task_struct *p)
1514{
1515 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1516}
1517
1518static inline int need_resched(void)
1519{
1520 return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1521}
1522
1523/*
1524 * cond_resched() and cond_resched_lock(): latency reduction via
1525 * explicit rescheduling in places that are safe. The return
1526 * value indicates whether a reschedule was done in fact.
1527 * cond_resched_lock() will drop the spinlock before scheduling,
1528 * cond_resched_softirq() will enable bhs before scheduling.
1529 */
1530extern int cond_resched(void);
1531extern int cond_resched_lock(spinlock_t * lock);
1532extern int cond_resched_softirq(void);
1533
1534/*
1535 * Does a critical section need to be broken due to another
1536 * task waiting?:
1537 */
1538#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
1539# define need_lockbreak(lock) ((lock)->break_lock)
1540#else
1541# define need_lockbreak(lock) 0
1542#endif
1543
1544/*
1545 * Does a critical section need to be broken due to another
1546 * task waiting or preemption being signalled:
1547 */
1548static inline int lock_need_resched(spinlock_t *lock)
1549{
1550 if (need_lockbreak(lock) || need_resched())
1551 return 1;
1552 return 0;
1553}
1554
1555/* Reevaluate whether the task has signals pending delivery.
1556 This is required every time the blocked sigset_t changes.
1557 callers must hold sighand->siglock. */
1558
1559extern FASTCALL(void recalc_sigpending_tsk(struct task_struct *t));
1560extern void recalc_sigpending(void);
1561
1562extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1563
1564/*
1565 * Wrappers for p->thread_info->cpu access. No-op on UP.
1566 */
1567#ifdef CONFIG_SMP
1568
1569static inline unsigned int task_cpu(const struct task_struct *p)
1570{
Al Viroa1261f52005-11-13 16:06:55 -08001571 return task_thread_info(p)->cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001572}
1573
1574static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1575{
Al Viroa1261f52005-11-13 16:06:55 -08001576 task_thread_info(p)->cpu = cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001577}
1578
1579#else
1580
1581static inline unsigned int task_cpu(const struct task_struct *p)
1582{
1583 return 0;
1584}
1585
1586static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1587{
1588}
1589
1590#endif /* CONFIG_SMP */
1591
1592#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1593extern void arch_pick_mmap_layout(struct mm_struct *mm);
1594#else
1595static inline void arch_pick_mmap_layout(struct mm_struct *mm)
1596{
1597 mm->mmap_base = TASK_UNMAPPED_BASE;
1598 mm->get_unmapped_area = arch_get_unmapped_area;
1599 mm->unmap_area = arch_unmap_area;
1600}
1601#endif
1602
1603extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
1604extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
1605
Siddha, Suresh B5c45bf22006-06-27 02:54:42 -07001606#include <linux/sysdev.h>
1607extern int sched_mc_power_savings, sched_smt_power_savings;
1608extern struct sysdev_attribute attr_sched_mc_power_savings, attr_sched_smt_power_savings;
1609extern int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls);
1610
Linus Torvalds1da177e2005-04-16 15:20:36 -07001611extern void normalize_rt_tasks(void);
1612
Linus Torvalds1da177e2005-04-16 15:20:36 -07001613#ifdef CONFIG_PM
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001614/*
1615 * Check if a process has been frozen
1616 */
1617static inline int frozen(struct task_struct *p)
1618{
1619 return p->flags & PF_FROZEN;
1620}
1621
1622/*
1623 * Check if there is a request to freeze a process
1624 */
1625static inline int freezing(struct task_struct *p)
1626{
1627 return p->flags & PF_FREEZE;
1628}
1629
1630/*
1631 * Request that a process be frozen
1632 * FIXME: SMP problem. We may not modify other process' flags!
1633 */
1634static inline void freeze(struct task_struct *p)
1635{
1636 p->flags |= PF_FREEZE;
1637}
1638
1639/*
Rafael J. Wysockia7ef7872006-08-05 12:13:42 -07001640 * Sometimes we may need to cancel the previous 'freeze' request
1641 */
1642static inline void do_not_freeze(struct task_struct *p)
1643{
1644 p->flags &= ~PF_FREEZE;
1645}
1646
1647/*
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001648 * Wake up a frozen process
1649 */
1650static inline int thaw_process(struct task_struct *p)
1651{
1652 if (frozen(p)) {
1653 p->flags &= ~PF_FROZEN;
1654 wake_up_process(p);
1655 return 1;
1656 }
1657 return 0;
1658}
1659
1660/*
1661 * freezing is complete, mark process as frozen
1662 */
1663static inline void frozen_process(struct task_struct *p)
1664{
1665 p->flags = (p->flags & ~PF_FREEZE) | PF_FROZEN;
1666}
1667
1668extern void refrigerator(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001669extern int freeze_processes(void);
1670extern void thaw_processes(void);
1671
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001672static inline int try_to_freeze(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001673{
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001674 if (freezing(current)) {
1675 refrigerator();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001676 return 1;
1677 } else
1678 return 0;
1679}
1680#else
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001681static inline int frozen(struct task_struct *p) { return 0; }
1682static inline int freezing(struct task_struct *p) { return 0; }
1683static inline void freeze(struct task_struct *p) { BUG(); }
1684static inline int thaw_process(struct task_struct *p) { return 1; }
1685static inline void frozen_process(struct task_struct *p) { BUG(); }
1686
1687static inline void refrigerator(void) {}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001688static inline int freeze_processes(void) { BUG(); return 0; }
1689static inline void thaw_processes(void) {}
1690
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001691static inline int try_to_freeze(void) { return 0; }
1692
Linus Torvalds1da177e2005-04-16 15:20:36 -07001693#endif /* CONFIG_PM */
1694#endif /* __KERNEL__ */
1695
1696#endif