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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
469 spinlock_t stats_lock;
470 struct taskstats *stats;
471#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472};
473
Nick Piggin4866cde2005-06-25 14:57:23 -0700474/* Context switch must be unlocked if interrupts are to be enabled */
475#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
476# define __ARCH_WANT_UNLOCKED_CTXSW
477#endif
478
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479/*
480 * Bits in flags field of signal_struct.
481 */
482#define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */
483#define SIGNAL_STOP_DEQUEUED 0x00000002 /* stop signal dequeued */
484#define SIGNAL_STOP_CONTINUED 0x00000004 /* SIGCONT since WCONTINUED reap */
485#define SIGNAL_GROUP_EXIT 0x00000008 /* group exit in progress */
486
487
488/*
489 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
Ingo Molnarb0a94992006-01-14 13:20:41 -0800490 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
491 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
492 * values are inverted: lower p->prio value means higher priority.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700493 *
494 * The MAX_USER_RT_PRIO value allows the actual maximum
495 * RT priority to be separate from the value exported to
496 * user-space. This allows kernel threads to set their
497 * priority to a value higher than any user task. Note:
498 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
499 */
500
501#define MAX_USER_RT_PRIO 100
502#define MAX_RT_PRIO MAX_USER_RT_PRIO
503
504#define MAX_PRIO (MAX_RT_PRIO + 40)
505
Ingo Molnarb29739f2006-06-27 02:54:51 -0700506#define rt_prio(prio) unlikely((prio) < MAX_RT_PRIO)
507#define rt_task(p) rt_prio((p)->prio)
Con Kolivasd425b272006-03-31 02:31:29 -0800508#define batch_task(p) (unlikely((p)->policy == SCHED_BATCH))
Oleg Nesterov57a6f512006-09-29 02:00:49 -0700509#define is_rt_policy(p) ((p) != SCHED_NORMAL && (p) != SCHED_BATCH)
510#define has_rt_policy(p) unlikely(is_rt_policy((p)->policy))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700511
512/*
513 * Some day this will be a full-fledged user tracking system..
514 */
515struct user_struct {
516 atomic_t __count; /* reference count */
517 atomic_t processes; /* How many processes does this user have? */
518 atomic_t files; /* How many open files does this user have? */
519 atomic_t sigpending; /* How many pending signals does this user have? */
Amy Griffis2d9048e2006-06-01 13:10:59 -0700520#ifdef CONFIG_INOTIFY_USER
Robert Love0eeca282005-07-12 17:06:03 -0400521 atomic_t inotify_watches; /* How many inotify watches does this user have? */
522 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */
523#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524 /* protected by mq_lock */
525 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
526 unsigned long locked_shm; /* How many pages of mlocked shm ? */
527
528#ifdef CONFIG_KEYS
529 struct key *uid_keyring; /* UID specific keyring */
530 struct key *session_keyring; /* UID's default session keyring */
531#endif
532
533 /* Hash table maintenance information */
534 struct list_head uidhash_list;
535 uid_t uid;
536};
537
538extern struct user_struct *find_user(uid_t);
539
540extern struct user_struct root_user;
541#define INIT_USER (&root_user)
542
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543struct backing_dev_info;
544struct reclaim_state;
545
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700546#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547struct sched_info {
548 /* cumulative counters */
549 unsigned long cpu_time, /* time spent on the cpu */
550 run_delay, /* time spent waiting on a runqueue */
551 pcnt; /* # of timeslices run on this cpu */
552
553 /* timestamps */
554 unsigned long last_arrival, /* when we last ran on a cpu */
555 last_queued; /* when we were last queued to run */
556};
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700557#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700559#ifdef CONFIG_SCHEDSTATS
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560extern struct file_operations proc_schedstat_operations;
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700561#endif /* CONFIG_SCHEDSTATS */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562
Shailabh Nagarca74e922006-07-14 00:24:36 -0700563#ifdef CONFIG_TASK_DELAY_ACCT
564struct task_delay_info {
565 spinlock_t lock;
566 unsigned int flags; /* Private per-task flags */
567
568 /* For each stat XXX, add following, aligned appropriately
569 *
570 * struct timespec XXX_start, XXX_end;
571 * u64 XXX_delay;
572 * u32 XXX_count;
573 *
574 * Atomicity of updates to XXX_delay, XXX_count protected by
575 * single lock above (split into XXX_lock if contention is an issue).
576 */
Shailabh Nagar0ff92242006-07-14 00:24:37 -0700577
578 /*
579 * XXX_count is incremented on every XXX operation, the delay
580 * associated with the operation is added to XXX_delay.
581 * XXX_delay contains the accumulated delay time in nanoseconds.
582 */
583 struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */
584 u64 blkio_delay; /* wait for sync block io completion */
585 u64 swapin_delay; /* wait for swapin block io completion */
586 u32 blkio_count; /* total count of the number of sync block */
587 /* io operations performed */
588 u32 swapin_count; /* total count of the number of swapin block */
589 /* io operations performed */
Shailabh Nagarca74e922006-07-14 00:24:36 -0700590};
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700591#endif /* CONFIG_TASK_DELAY_ACCT */
592
593static inline int sched_info_on(void)
594{
595#ifdef CONFIG_SCHEDSTATS
596 return 1;
597#elif defined(CONFIG_TASK_DELAY_ACCT)
598 extern int delayacct_on;
599 return delayacct_on;
600#else
601 return 0;
Shailabh Nagarca74e922006-07-14 00:24:36 -0700602#endif
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700603}
Shailabh Nagarca74e922006-07-14 00:24:36 -0700604
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605enum idle_type
606{
607 SCHED_IDLE,
608 NOT_IDLE,
609 NEWLY_IDLE,
610 MAX_IDLE_TYPES
611};
612
613/*
614 * sched-domains (multiprocessor balancing) declarations:
615 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616#define SCHED_LOAD_SCALE 128UL /* increase resolution of load */
617
Peter Williams2dd73a42006-06-27 02:54:34 -0700618#ifdef CONFIG_SMP
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619#define SD_LOAD_BALANCE 1 /* Do load balancing on this domain. */
620#define SD_BALANCE_NEWIDLE 2 /* Balance when about to become idle */
621#define SD_BALANCE_EXEC 4 /* Balance on exec */
Nick Piggin147cbb42005-06-25 14:57:19 -0700622#define SD_BALANCE_FORK 8 /* Balance on fork, clone */
623#define SD_WAKE_IDLE 16 /* Wake to idle CPU on task wakeup */
624#define SD_WAKE_AFFINE 32 /* Wake task to waking CPU */
625#define SD_WAKE_BALANCE 64 /* Perform balancing at task wakeup */
626#define SD_SHARE_CPUPOWER 128 /* Domain members share cpu power */
Siddha, Suresh B5c45bf22006-06-27 02:54:42 -0700627#define SD_POWERSAVINGS_BALANCE 256 /* Balance for power savings */
Siddha, Suresh B89c47102006-10-03 01:14:09 -0700628#define SD_SHARE_PKG_RESOURCES 512 /* Domain members share cpu pkg resources */
Siddha, Suresh B5c45bf22006-06-27 02:54:42 -0700629
Siddha, Suresh B89c47102006-10-03 01:14:09 -0700630#define BALANCE_FOR_MC_POWER \
631 (sched_smt_power_savings ? SD_POWERSAVINGS_BALANCE : 0)
632
633#define BALANCE_FOR_PKG_POWER \
634 ((sched_mc_power_savings || sched_smt_power_savings) ? \
635 SD_POWERSAVINGS_BALANCE : 0)
636
637#define test_sd_parent(sd, flag) ((sd->parent && \
638 (sd->parent->flags & flag)) ? 1 : 0)
Siddha, Suresh B5c45bf22006-06-27 02:54:42 -0700639
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640
641struct sched_group {
642 struct sched_group *next; /* Must be a circular list */
643 cpumask_t cpumask;
644
645 /*
646 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
647 * single CPU. This is read only (except for setup, hotplug CPU).
648 */
649 unsigned long cpu_power;
650};
651
652struct sched_domain {
653 /* These fields must be setup */
654 struct sched_domain *parent; /* top domain must be null terminated */
Siddha, Suresh B1a848872006-10-03 01:14:08 -0700655 struct sched_domain *child; /* bottom domain must be null terminated */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700656 struct sched_group *groups; /* the balancing groups of the domain */
657 cpumask_t span; /* span of all CPUs in this domain */
658 unsigned long min_interval; /* Minimum balance interval ms */
659 unsigned long max_interval; /* Maximum balance interval ms */
660 unsigned int busy_factor; /* less balancing by factor if busy */
661 unsigned int imbalance_pct; /* No balance until over watermark */
662 unsigned long long cache_hot_time; /* Task considered cache hot (ns) */
663 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */
664 unsigned int per_cpu_gain; /* CPU % gained by adding domain cpus */
Nick Piggin78979862005-06-25 14:57:13 -0700665 unsigned int busy_idx;
666 unsigned int idle_idx;
667 unsigned int newidle_idx;
668 unsigned int wake_idx;
Nick Piggin147cbb42005-06-25 14:57:19 -0700669 unsigned int forkexec_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700670 int flags; /* See SD_* */
671
672 /* Runtime fields. */
673 unsigned long last_balance; /* init to jiffies. units in jiffies */
674 unsigned int balance_interval; /* initialise to 1. units in ms. */
675 unsigned int nr_balance_failed; /* initialise to 0 */
676
677#ifdef CONFIG_SCHEDSTATS
678 /* load_balance() stats */
679 unsigned long lb_cnt[MAX_IDLE_TYPES];
680 unsigned long lb_failed[MAX_IDLE_TYPES];
681 unsigned long lb_balanced[MAX_IDLE_TYPES];
682 unsigned long lb_imbalance[MAX_IDLE_TYPES];
683 unsigned long lb_gained[MAX_IDLE_TYPES];
684 unsigned long lb_hot_gained[MAX_IDLE_TYPES];
685 unsigned long lb_nobusyg[MAX_IDLE_TYPES];
686 unsigned long lb_nobusyq[MAX_IDLE_TYPES];
687
688 /* Active load balancing */
689 unsigned long alb_cnt;
690 unsigned long alb_failed;
691 unsigned long alb_pushed;
692
Nick Piggin68767a02005-06-25 14:57:20 -0700693 /* SD_BALANCE_EXEC stats */
694 unsigned long sbe_cnt;
695 unsigned long sbe_balanced;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696 unsigned long sbe_pushed;
697
Nick Piggin68767a02005-06-25 14:57:20 -0700698 /* SD_BALANCE_FORK stats */
699 unsigned long sbf_cnt;
700 unsigned long sbf_balanced;
701 unsigned long sbf_pushed;
702
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703 /* try_to_wake_up() stats */
704 unsigned long ttwu_wake_remote;
705 unsigned long ttwu_move_affine;
706 unsigned long ttwu_move_balance;
707#endif
708};
709
Srivatsa Vaddagiri51888ca2006-06-27 02:54:38 -0700710extern int partition_sched_domains(cpumask_t *partition1,
Dinakar Guniguntala1a20ff22005-06-25 14:57:33 -0700711 cpumask_t *partition2);
akpm@osdl.org198e2f12006-01-12 01:05:30 -0800712
713/*
714 * Maximum cache size the migration-costs auto-tuning code will
715 * search from:
716 */
717extern unsigned int max_cache_size;
718
719#endif /* CONFIG_SMP */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720
721
722struct io_context; /* See blkdev.h */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700723struct cpuset;
724
725#define NGROUPS_SMALL 32
726#define NGROUPS_PER_BLOCK ((int)(PAGE_SIZE / sizeof(gid_t)))
727struct group_info {
728 int ngroups;
729 atomic_t usage;
730 gid_t small_block[NGROUPS_SMALL];
731 int nblocks;
732 gid_t *blocks[0];
733};
734
735/*
736 * get_group_info() must be called with the owning task locked (via task_lock())
737 * when task != current. The reason being that the vast majority of callers are
738 * looking at current->group_info, which can not be changed except by the
739 * current task. Changing current->group_info requires the task lock, too.
740 */
741#define get_group_info(group_info) do { \
742 atomic_inc(&(group_info)->usage); \
743} while (0)
744
745#define put_group_info(group_info) do { \
746 if (atomic_dec_and_test(&(group_info)->usage)) \
747 groups_free(group_info); \
748} while (0)
749
David Howells3e301482005-06-23 22:00:56 -0700750extern struct group_info *groups_alloc(int gidsetsize);
751extern void groups_free(struct group_info *group_info);
752extern int set_current_groups(struct group_info *group_info);
753extern int groups_search(struct group_info *group_info, gid_t grp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700754/* access the groups "array" with this macro */
755#define GROUP_AT(gi, i) \
756 ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
757
Chen, Kenneth W383f2832005-09-09 13:02:02 -0700758#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
Ingo Molnar36c8b582006-07-03 00:25:41 -0700759extern void prefetch_stack(struct task_struct *t);
Chen, Kenneth W383f2832005-09-09 13:02:02 -0700760#else
761static inline void prefetch_stack(struct task_struct *t) { }
762#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763
764struct audit_context; /* See audit.c */
765struct mempolicy;
Jens Axboeb92ce552006-04-11 13:52:07 +0200766struct pipe_inode_info;
Serge E. Hallyn4865ecf2006-10-02 02:18:14 -0700767struct uts_namespace;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700768
Con Kolivas3dee3862006-03-31 02:31:23 -0800769enum sleep_type {
770 SLEEP_NORMAL,
771 SLEEP_NONINTERACTIVE,
772 SLEEP_INTERACTIVE,
773 SLEEP_INTERRUPTED,
774};
775
Ingo Molnar70b97a72006-07-03 00:25:42 -0700776struct prio_array;
777
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778struct task_struct {
779 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
780 struct thread_info *thread_info;
781 atomic_t usage;
782 unsigned long flags; /* per process flags, defined below */
783 unsigned long ptrace;
784
Paolo 'Blaisorblade' Giarrusso36772092005-05-05 16:16:12 -0700785 int lock_depth; /* BKL lock depth */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786
Peter Williams2dd73a42006-06-27 02:54:34 -0700787#ifdef CONFIG_SMP
788#ifdef __ARCH_WANT_UNLOCKED_CTXSW
Nick Piggin4866cde2005-06-25 14:57:23 -0700789 int oncpu;
790#endif
Peter Williams2dd73a42006-06-27 02:54:34 -0700791#endif
792 int load_weight; /* for niceness load balancing purposes */
Ingo Molnarb29739f2006-06-27 02:54:51 -0700793 int prio, static_prio, normal_prio;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794 struct list_head run_list;
Ingo Molnar70b97a72006-07-03 00:25:42 -0700795 struct prio_array *array;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796
Jens Axboe22e2c502005-06-27 10:55:12 +0200797 unsigned short ioprio;
Alexey Dobriyan6c5c9342006-09-29 01:59:40 -0700798#ifdef CONFIG_BLK_DEV_IO_TRACE
Jens Axboe2056a782006-03-23 20:00:26 +0100799 unsigned int btrace_seq;
Alexey Dobriyan6c5c9342006-09-29 01:59:40 -0700800#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700801 unsigned long sleep_avg;
802 unsigned long long timestamp, last_ran;
803 unsigned long long sched_time; /* sched_clock time spent running */
Con Kolivas3dee3862006-03-31 02:31:23 -0800804 enum sleep_type sleep_type;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805
806 unsigned long policy;
807 cpumask_t cpus_allowed;
808 unsigned int time_slice, first_time_slice;
809
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700810#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700811 struct sched_info sched_info;
812#endif
813
814 struct list_head tasks;
815 /*
816 * ptrace_list/ptrace_children forms the list of my children
817 * that were stolen by a ptracer.
818 */
819 struct list_head ptrace_children;
820 struct list_head ptrace_list;
821
822 struct mm_struct *mm, *active_mm;
823
824/* task state */
825 struct linux_binfmt *binfmt;
826 long exit_state;
827 int exit_code, exit_signal;
828 int pdeath_signal; /* The signal sent when the parent dies */
829 /* ??? */
830 unsigned long personality;
831 unsigned did_exec:1;
832 pid_t pid;
833 pid_t tgid;
Arjan van de Ven0a425402006-09-26 10:52:38 +0200834
835#ifdef CONFIG_CC_STACKPROTECTOR
836 /* Canary value for the -fstack-protector gcc feature */
837 unsigned long stack_canary;
838#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839 /*
840 * pointers to (original) parent process, youngest child, younger sibling,
841 * older sibling, respectively. (p->father can be replaced with
842 * p->parent->pid)
843 */
844 struct task_struct *real_parent; /* real parent process (when being debugged) */
845 struct task_struct *parent; /* parent process */
846 /*
847 * children/sibling forms the list of my children plus the
848 * tasks I'm ptracing.
849 */
850 struct list_head children; /* list of my children */
851 struct list_head sibling; /* linkage in my parent's children list */
852 struct task_struct *group_leader; /* threadgroup leader */
853
854 /* PID/PID hash table linkage. */
Eric W. Biederman92476d72006-03-31 02:31:42 -0800855 struct pid_link pids[PIDTYPE_MAX];
Oleg Nesterov47e65322006-03-28 16:11:25 -0800856 struct list_head thread_group;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857
858 struct completion *vfork_done; /* for vfork() */
859 int __user *set_child_tid; /* CLONE_CHILD_SETTID */
860 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
861
862 unsigned long rt_priority;
863 cputime_t utime, stime;
864 unsigned long nvcsw, nivcsw; /* context switch counts */
865 struct timespec start_time;
866/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
867 unsigned long min_flt, maj_flt;
868
869 cputime_t it_prof_expires, it_virt_expires;
870 unsigned long long it_sched_expires;
871 struct list_head cpu_timers[3];
872
873/* process credentials */
874 uid_t uid,euid,suid,fsuid;
875 gid_t gid,egid,sgid,fsgid;
876 struct group_info *group_info;
877 kernel_cap_t cap_effective, cap_inheritable, cap_permitted;
878 unsigned keep_capabilities:1;
879 struct user_struct *user;
880#ifdef CONFIG_KEYS
David Howellsb5f545c2006-01-08 01:02:47 -0800881 struct key *request_key_auth; /* assumed request_key authority */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700882 struct key *thread_keyring; /* keyring private to this thread */
David Howells3e301482005-06-23 22:00:56 -0700883 unsigned char jit_keyring; /* default keyring to attach requested keys to */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884#endif
Arjan van de Vene07e23e2006-09-26 10:52:36 +0200885 /*
886 * fpu_counter contains the number of consecutive context switches
887 * that the FPU is used. If this is over a threshold, the lazy fpu
888 * saving becomes unlazy to save the trap. This is an unsigned char
889 * so that after 256 times the counter wraps and the behavior turns
890 * lazy again; this to deal with bursty apps that only use FPU for
891 * a short time
892 */
893 unsigned char fpu_counter;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700894 int oomkilladj; /* OOM kill score adjustment (bit shift). */
Paolo 'Blaisorblade' Giarrusso36772092005-05-05 16:16:12 -0700895 char comm[TASK_COMM_LEN]; /* executable name excluding path
896 - access with [gs]et_task_comm (which lock
897 it with task_lock())
898 - initialized normally by flush_old_exec */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700899/* file system info */
900 int link_count, total_link_count;
Alexey Dobriyan3d5b6fc2006-09-29 01:59:40 -0700901#ifdef CONFIG_SYSVIPC
Linus Torvalds1da177e2005-04-16 15:20:36 -0700902/* ipc stuff */
903 struct sysv_sem sysvsem;
Alexey Dobriyan3d5b6fc2006-09-29 01:59:40 -0700904#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905/* CPU-specific state of this task */
906 struct thread_struct thread;
907/* filesystem information */
908 struct fs_struct *fs;
909/* open file information */
910 struct files_struct *files;
Serge E. Hallyn1651e142006-10-02 02:18:08 -0700911/* namespaces */
Serge E. Hallynab516012006-10-02 02:18:06 -0700912 struct nsproxy *nsproxy;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700913/* signal handlers */
914 struct signal_struct *signal;
915 struct sighand_struct *sighand;
916
917 sigset_t blocked, real_blocked;
David Woodhouse150256d2006-01-18 17:43:57 -0800918 sigset_t saved_sigmask; /* To be restored with TIF_RESTORE_SIGMASK */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700919 struct sigpending pending;
920
921 unsigned long sas_ss_sp;
922 size_t sas_ss_size;
923 int (*notifier)(void *priv);
924 void *notifier_data;
925 sigset_t *notifier_mask;
926
927 void *security;
928 struct audit_context *audit_context;
929 seccomp_t seccomp;
930
931/* Thread group tracking */
932 u32 parent_exec_id;
933 u32 self_exec_id;
934/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
935 spinlock_t alloc_lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700936
Ingo Molnarb29739f2006-06-27 02:54:51 -0700937 /* Protection of the PI data structures: */
938 spinlock_t pi_lock;
939
Ingo Molnar23f78d4a2006-06-27 02:54:53 -0700940#ifdef CONFIG_RT_MUTEXES
941 /* PI waiters blocked on a rt_mutex held by this task */
942 struct plist_head pi_waiters;
943 /* Deadlock detection and priority inheritance handling */
944 struct rt_mutex_waiter *pi_blocked_on;
Ingo Molnar23f78d4a2006-06-27 02:54:53 -0700945#endif
946
Ingo Molnar408894e2006-01-09 15:59:20 -0800947#ifdef CONFIG_DEBUG_MUTEXES
948 /* mutex deadlock detection */
949 struct mutex_waiter *blocked_on;
950#endif
Ingo Molnarde30a2b2006-07-03 00:24:42 -0700951#ifdef CONFIG_TRACE_IRQFLAGS
952 unsigned int irq_events;
953 int hardirqs_enabled;
954 unsigned long hardirq_enable_ip;
955 unsigned int hardirq_enable_event;
956 unsigned long hardirq_disable_ip;
957 unsigned int hardirq_disable_event;
958 int softirqs_enabled;
959 unsigned long softirq_disable_ip;
960 unsigned int softirq_disable_event;
961 unsigned long softirq_enable_ip;
962 unsigned int softirq_enable_event;
963 int hardirq_context;
964 int softirq_context;
965#endif
Ingo Molnarfbb9ce952006-07-03 00:24:50 -0700966#ifdef CONFIG_LOCKDEP
967# define MAX_LOCK_DEPTH 30UL
968 u64 curr_chain_key;
969 int lockdep_depth;
970 struct held_lock held_locks[MAX_LOCK_DEPTH];
971 unsigned int lockdep_recursion;
972#endif
Ingo Molnar408894e2006-01-09 15:59:20 -0800973
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974/* journalling filesystem info */
975 void *journal_info;
976
977/* VM state */
978 struct reclaim_state *reclaim_state;
979
Linus Torvalds1da177e2005-04-16 15:20:36 -0700980 struct backing_dev_info *backing_dev_info;
981
982 struct io_context *io_context;
983
984 unsigned long ptrace_message;
985 siginfo_t *last_siginfo; /* For ptrace use. */
986/*
987 * current io wait handle: wait queue entry to use for io waits
988 * If this thread is processing aio, this points at the waitqueue
989 * inside the currently handled kiocb. It may be NULL (i.e. default
990 * to a stack based synchronous wait) if its doing sync IO.
991 */
992 wait_queue_t *io_wait;
993/* i/o counters(bytes read/written, #syscalls */
994 u64 rchar, wchar, syscr, syscw;
Jay Lan8f0ab512006-09-30 23:28:59 -0700995#if defined(CONFIG_TASK_XACCT)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700996 u64 acct_rss_mem1; /* accumulated rss usage */
997 u64 acct_vm_mem1; /* accumulated virtual memory usage */
Jay Landb5fed262006-09-30 23:29:00 -0700998 cputime_t acct_stimexpd;/* stime since last update */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700999#endif
1000#ifdef CONFIG_NUMA
1001 struct mempolicy *mempolicy;
1002 short il_next;
1003#endif
1004#ifdef CONFIG_CPUSETS
1005 struct cpuset *cpuset;
1006 nodemask_t mems_allowed;
1007 int cpuset_mems_generation;
Paul Jackson825a46a2006-03-24 03:16:03 -08001008 int cpuset_mem_spread_rotor;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001009#endif
Ingo Molnar0771dfe2006-03-27 01:16:22 -08001010 struct robust_list_head __user *robust_list;
Ingo Molnar34f192c2006-03-27 01:16:24 -08001011#ifdef CONFIG_COMPAT
1012 struct compat_robust_list_head __user *compat_robust_list;
1013#endif
Ingo Molnarc87e2832006-06-27 02:54:58 -07001014 struct list_head pi_state_list;
1015 struct futex_pi_state *pi_state_cache;
Ingo Molnar0771dfe2006-03-27 01:16:22 -08001016
Jens Axboe22e2c502005-06-27 10:55:12 +02001017 atomic_t fs_excl; /* holding fs exclusive resources */
Ingo Molnare56d0902006-01-08 01:01:37 -08001018 struct rcu_head rcu;
Jens Axboeb92ce552006-04-11 13:52:07 +02001019
1020 /*
1021 * cache last used pipe for splice
1022 */
1023 struct pipe_inode_info *splice_pipe;
Shailabh Nagarca74e922006-07-14 00:24:36 -07001024#ifdef CONFIG_TASK_DELAY_ACCT
1025 struct task_delay_info *delays;
1026#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001027};
1028
1029static inline pid_t process_group(struct task_struct *tsk)
1030{
1031 return tsk->signal->pgrp;
1032}
1033
Eric W. Biederman22c935f2006-10-02 02:17:09 -07001034static inline struct pid *task_pid(struct task_struct *task)
1035{
1036 return task->pids[PIDTYPE_PID].pid;
1037}
1038
1039static inline struct pid *task_tgid(struct task_struct *task)
1040{
1041 return task->group_leader->pids[PIDTYPE_PID].pid;
1042}
1043
1044static inline struct pid *task_pgrp(struct task_struct *task)
1045{
1046 return task->group_leader->pids[PIDTYPE_PGID].pid;
1047}
1048
1049static inline struct pid *task_session(struct task_struct *task)
1050{
1051 return task->group_leader->pids[PIDTYPE_SID].pid;
1052}
1053
Linus Torvalds1da177e2005-04-16 15:20:36 -07001054/**
1055 * pid_alive - check that a task structure is not stale
1056 * @p: Task structure to be checked.
1057 *
1058 * Test if a process is not yet dead (at most zombie state)
1059 * If pid_alive fails, then pointers within the task structure
1060 * can be stale and must not be dereferenced.
1061 */
1062static inline int pid_alive(struct task_struct *p)
1063{
Eric W. Biederman92476d72006-03-31 02:31:42 -08001064 return p->pids[PIDTYPE_PID].pid != NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001065}
1066
Sukadev Bhattiproluf400e192006-09-29 02:00:07 -07001067/**
Henne32602592006-10-06 00:44:01 -07001068 * is_init - check if a task structure is init
1069 * @tsk: Task structure to be checked.
1070 *
1071 * Check if a task structure is the first user space task the kernel created.
Sukadev Bhattiproluf400e192006-09-29 02:00:07 -07001072 */
1073static inline int is_init(struct task_struct *tsk)
1074{
1075 return tsk->pid == 1;
1076}
1077
Cedric Le Goater9ec52092006-10-02 02:19:00 -07001078extern struct pid *cad_pid;
1079
Linus Torvalds1da177e2005-04-16 15:20:36 -07001080extern void free_task(struct task_struct *tsk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001081#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
Ingo Molnare56d0902006-01-08 01:01:37 -08001082
Andrew Morton158d9eb2006-03-31 02:31:34 -08001083extern void __put_task_struct(struct task_struct *t);
Ingo Molnare56d0902006-01-08 01:01:37 -08001084
1085static inline void put_task_struct(struct task_struct *t)
1086{
1087 if (atomic_dec_and_test(&t->usage))
Eric W. Biederman8c7904a2006-03-31 02:31:37 -08001088 __put_task_struct(t);
Ingo Molnare56d0902006-01-08 01:01:37 -08001089}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001090
1091/*
1092 * Per process flags
1093 */
1094#define PF_ALIGNWARN 0x00000001 /* Print alignment warning msgs */
1095 /* Not implemented yet, only for 486*/
1096#define PF_STARTING 0x00000002 /* being created */
1097#define PF_EXITING 0x00000004 /* getting shut down */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001098#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
1099#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
1100#define PF_DUMPCORE 0x00000200 /* dumped core */
1101#define PF_SIGNALED 0x00000400 /* killed by a signal */
1102#define PF_MEMALLOC 0x00000800 /* Allocating memory */
1103#define PF_FLUSHER 0x00001000 /* responsible for disk writeback */
1104#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
1105#define PF_FREEZE 0x00004000 /* this task is being frozen for suspend now */
1106#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
1107#define PF_FROZEN 0x00010000 /* frozen for system suspend */
1108#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
1109#define PF_KSWAPD 0x00040000 /* I am kswapd */
1110#define PF_SWAPOFF 0x00080000 /* I am in swapoff */
1111#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
Jens Axboeb31dc662006-06-13 08:26:10 +02001112#define PF_BORROWED_MM 0x00200000 /* I am a kthread doing use_mm */
1113#define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */
1114#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1115#define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */
1116#define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */
Paul Jacksonc61afb12006-03-24 03:16:08 -08001117#define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */
Thomas Gleixner61a87122006-06-27 02:54:56 -07001118#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001119
1120/*
1121 * Only the _current_ task can read/write to tsk->flags, but other
1122 * tasks can access tsk->flags in readonly mode for example
1123 * with tsk_used_math (like during threaded core dumping).
1124 * There is however an exception to this rule during ptrace
1125 * or during fork: the ptracer task is allowed to write to the
1126 * child->flags of its traced child (same goes for fork, the parent
1127 * can write to the child->flags), because we're guaranteed the
1128 * child is not running and in turn not changing child->flags
1129 * at the same time the parent does it.
1130 */
1131#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1132#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1133#define clear_used_math() clear_stopped_child_used_math(current)
1134#define set_used_math() set_stopped_child_used_math(current)
1135#define conditional_stopped_child_used_math(condition, child) \
1136 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1137#define conditional_used_math(condition) \
1138 conditional_stopped_child_used_math(condition, current)
1139#define copy_to_stopped_child_used_math(child) \
1140 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1141/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1142#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1143#define used_math() tsk_used_math(current)
1144
1145#ifdef CONFIG_SMP
Ingo Molnar36c8b582006-07-03 00:25:41 -07001146extern int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001147#else
Ingo Molnar36c8b582006-07-03 00:25:41 -07001148static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001149{
Paul Jackson4098f992005-10-30 15:03:21 -08001150 if (!cpu_isset(0, new_mask))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001151 return -EINVAL;
1152 return 0;
1153}
1154#endif
1155
1156extern unsigned long long sched_clock(void);
Ingo Molnar36c8b582006-07-03 00:25:41 -07001157extern unsigned long long
1158current_sched_time(const struct task_struct *current_task);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001159
1160/* sched_exec is called by processes performing an exec */
1161#ifdef CONFIG_SMP
1162extern void sched_exec(void);
1163#else
1164#define sched_exec() {}
1165#endif
1166
1167#ifdef CONFIG_HOTPLUG_CPU
1168extern void idle_task_exit(void);
1169#else
1170static inline void idle_task_exit(void) {}
1171#endif
1172
1173extern void sched_idle_next(void);
Ingo Molnarb29739f2006-06-27 02:54:51 -07001174
1175#ifdef CONFIG_RT_MUTEXES
Ingo Molnar36c8b582006-07-03 00:25:41 -07001176extern int rt_mutex_getprio(struct task_struct *p);
1177extern void rt_mutex_setprio(struct task_struct *p, int prio);
1178extern void rt_mutex_adjust_pi(struct task_struct *p);
Ingo Molnarb29739f2006-06-27 02:54:51 -07001179#else
Ingo Molnar36c8b582006-07-03 00:25:41 -07001180static inline int rt_mutex_getprio(struct task_struct *p)
Ingo Molnarb29739f2006-06-27 02:54:51 -07001181{
1182 return p->normal_prio;
1183}
Thomas Gleixner95e02ca2006-06-27 02:55:02 -07001184# define rt_mutex_adjust_pi(p) do { } while (0)
Ingo Molnarb29739f2006-06-27 02:54:51 -07001185#endif
1186
Ingo Molnar36c8b582006-07-03 00:25:41 -07001187extern void set_user_nice(struct task_struct *p, long nice);
1188extern int task_prio(const struct task_struct *p);
1189extern int task_nice(const struct task_struct *p);
1190extern int can_nice(const struct task_struct *p, const int nice);
1191extern int task_curr(const struct task_struct *p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001192extern int idle_cpu(int cpu);
1193extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
Ingo Molnar36c8b582006-07-03 00:25:41 -07001194extern struct task_struct *idle_task(int cpu);
1195extern struct task_struct *curr_task(int cpu);
1196extern void set_curr_task(int cpu, struct task_struct *p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001197
1198void yield(void);
1199
1200/*
1201 * The default (Linux) execution domain.
1202 */
1203extern struct exec_domain default_exec_domain;
1204
1205union thread_union {
1206 struct thread_info thread_info;
1207 unsigned long stack[THREAD_SIZE/sizeof(long)];
1208};
1209
1210#ifndef __HAVE_ARCH_KSTACK_END
1211static inline int kstack_end(void *addr)
1212{
1213 /* Reliable end of stack detection:
1214 * Some APM bios versions misalign the stack
1215 */
1216 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1217}
1218#endif
1219
1220extern union thread_union init_thread_union;
1221extern struct task_struct init_task;
1222
1223extern struct mm_struct init_mm;
1224
1225#define find_task_by_pid(nr) find_task_by_pid_type(PIDTYPE_PID, nr)
1226extern struct task_struct *find_task_by_pid_type(int type, int pid);
1227extern void set_special_pids(pid_t session, pid_t pgrp);
1228extern void __set_special_pids(pid_t session, pid_t pgrp);
1229
1230/* per-UID process charging. */
1231extern struct user_struct * alloc_uid(uid_t);
1232static inline struct user_struct *get_uid(struct user_struct *u)
1233{
1234 atomic_inc(&u->__count);
1235 return u;
1236}
1237extern void free_uid(struct user_struct *);
1238extern void switch_uid(struct user_struct *);
1239
1240#include <asm/current.h>
1241
Atsushi Nemoto3171a032006-09-29 02:00:32 -07001242extern void do_timer(unsigned long ticks);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001243
1244extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state));
1245extern int FASTCALL(wake_up_process(struct task_struct * tsk));
1246extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
1247 unsigned long clone_flags));
1248#ifdef CONFIG_SMP
1249 extern void kick_process(struct task_struct *tsk);
1250#else
1251 static inline void kick_process(struct task_struct *tsk) { }
1252#endif
Ingo Molnar36c8b582006-07-03 00:25:41 -07001253extern void FASTCALL(sched_fork(struct task_struct * p, int clone_flags));
1254extern void FASTCALL(sched_exit(struct task_struct * p));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001255
1256extern int in_group_p(gid_t);
1257extern int in_egroup_p(gid_t);
1258
1259extern void proc_caches_init(void);
1260extern void flush_signals(struct task_struct *);
1261extern void flush_signal_handlers(struct task_struct *, int force_default);
1262extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1263
1264static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1265{
1266 unsigned long flags;
1267 int ret;
1268
1269 spin_lock_irqsave(&tsk->sighand->siglock, flags);
1270 ret = dequeue_signal(tsk, mask, info);
1271 spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1272
1273 return ret;
1274}
1275
1276extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1277 sigset_t *mask);
1278extern void unblock_all_signals(void);
1279extern void release_task(struct task_struct * p);
1280extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1281extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
1282extern int force_sigsegv(int, struct task_struct *);
1283extern int force_sig_info(int, struct siginfo *, struct task_struct *);
Eric W. Biedermanc4b92fc2006-10-02 02:17:10 -07001284extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1285extern int kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1286extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
Eric W. Biederman2425c082006-10-02 02:17:28 -07001287extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
Eric W. Biedermanc4b92fc2006-10-02 02:17:10 -07001288extern int kill_pgrp(struct pid *pid, int sig, int priv);
1289extern int kill_pid(struct pid *pid, int sig, int priv);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001290extern int __kill_pg_info(int sig, struct siginfo *info, pid_t pgrp);
1291extern int kill_pg_info(int, struct siginfo *, pid_t);
1292extern int kill_proc_info(int, struct siginfo *, pid_t);
1293extern void do_notify_parent(struct task_struct *, int);
1294extern void force_sig(int, struct task_struct *);
1295extern void force_sig_specific(int, struct task_struct *);
1296extern int send_sig(int, struct task_struct *, int);
1297extern void zap_other_threads(struct task_struct *p);
1298extern int kill_pg(pid_t, int, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001299extern int kill_proc(pid_t, int, int);
1300extern struct sigqueue *sigqueue_alloc(void);
1301extern void sigqueue_free(struct sigqueue *);
1302extern int send_sigqueue(int, struct sigqueue *, struct task_struct *);
1303extern int send_group_sigqueue(int, struct sigqueue *, struct task_struct *);
Oleg Nesterov9ac95f22006-02-09 22:41:50 +03001304extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001305extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1306
Cedric Le Goater9ec52092006-10-02 02:19:00 -07001307static inline int kill_cad_pid(int sig, int priv)
1308{
1309 return kill_pid(cad_pid, sig, priv);
1310}
1311
Linus Torvalds1da177e2005-04-16 15:20:36 -07001312/* These can be the second arg to send_sig_info/send_group_sig_info. */
1313#define SEND_SIG_NOINFO ((struct siginfo *) 0)
1314#define SEND_SIG_PRIV ((struct siginfo *) 1)
1315#define SEND_SIG_FORCED ((struct siginfo *) 2)
1316
Oleg Nesterov621d3122005-10-30 15:03:45 -08001317static inline int is_si_special(const struct siginfo *info)
1318{
1319 return info <= SEND_SIG_FORCED;
1320}
1321
Linus Torvalds1da177e2005-04-16 15:20:36 -07001322/* True if we are on the alternate signal stack. */
1323
1324static inline int on_sig_stack(unsigned long sp)
1325{
1326 return (sp - current->sas_ss_sp < current->sas_ss_size);
1327}
1328
1329static inline int sas_ss_flags(unsigned long sp)
1330{
1331 return (current->sas_ss_size == 0 ? SS_DISABLE
1332 : on_sig_stack(sp) ? SS_ONSTACK : 0);
1333}
1334
Linus Torvalds1da177e2005-04-16 15:20:36 -07001335/*
1336 * Routines for handling mm_structs
1337 */
1338extern struct mm_struct * mm_alloc(void);
1339
1340/* mmdrop drops the mm and the page tables */
1341extern void FASTCALL(__mmdrop(struct mm_struct *));
1342static inline void mmdrop(struct mm_struct * mm)
1343{
1344 if (atomic_dec_and_test(&mm->mm_count))
1345 __mmdrop(mm);
1346}
1347
1348/* mmput gets rid of the mappings and all user-space */
1349extern void mmput(struct mm_struct *);
1350/* Grab a reference to a task's mm, if it is not already going away */
1351extern struct mm_struct *get_task_mm(struct task_struct *task);
1352/* Remove the current tasks stale references to the old mm_struct */
1353extern void mm_release(struct task_struct *, struct mm_struct *);
1354
1355extern int copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1356extern void flush_thread(void);
1357extern void exit_thread(void);
1358
Linus Torvalds1da177e2005-04-16 15:20:36 -07001359extern void exit_files(struct task_struct *);
Oleg Nesterov6b3934e2006-03-28 16:11:16 -08001360extern void __cleanup_signal(struct signal_struct *);
Oleg Nesterova7e53282006-03-28 16:11:27 -08001361extern void __cleanup_sighand(struct sighand_struct *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001362extern void exit_itimers(struct signal_struct *);
1363
1364extern NORET_TYPE void do_group_exit(int);
1365
Linus Torvalds1da177e2005-04-16 15:20:36 -07001366extern void daemonize(const char *, ...);
1367extern int allow_signal(int);
1368extern int disallow_signal(int);
Ingo Molnar36c8b582006-07-03 00:25:41 -07001369extern struct task_struct *child_reaper;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001370
1371extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1372extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
Ingo Molnar36c8b582006-07-03 00:25:41 -07001373struct task_struct *fork_idle(int);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001374
1375extern void set_task_comm(struct task_struct *tsk, char *from);
1376extern void get_task_comm(char *to, struct task_struct *tsk);
1377
1378#ifdef CONFIG_SMP
Ingo Molnar36c8b582006-07-03 00:25:41 -07001379extern void wait_task_inactive(struct task_struct * p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001380#else
1381#define wait_task_inactive(p) do { } while (0)
1382#endif
1383
1384#define remove_parent(p) list_del_init(&(p)->sibling)
Oleg Nesterov8fafabd2006-03-28 16:11:05 -08001385#define add_parent(p) list_add_tail(&(p)->sibling,&(p)->parent->children)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001386
Eric W. Biederman5e85d4a2006-04-18 22:20:16 -07001387#define next_task(p) list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001388
1389#define for_each_process(p) \
1390 for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1391
1392/*
1393 * Careful: do_each_thread/while_each_thread is a double loop so
1394 * 'break' will not work as expected - use goto instead.
1395 */
1396#define do_each_thread(g, t) \
1397 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1398
1399#define while_each_thread(g, t) \
1400 while ((t = next_thread(t)) != g)
1401
Eric W. Biedermande12a782006-04-10 17:16:49 -06001402/* de_thread depends on thread_group_leader not being a pid based check */
1403#define thread_group_leader(p) (p == p->group_leader)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001404
Eric W. Biederman0804ef42006-10-02 02:17:04 -07001405/* Do to the insanities of de_thread it is possible for a process
1406 * to have the pid of the thread group leader without actually being
1407 * the thread group leader. For iteration through the pids in proc
1408 * all we care about is that we have a task with the appropriate
1409 * pid, we don't actually care if we have the right task.
1410 */
1411static inline int has_group_leader_pid(struct task_struct *p)
1412{
1413 return p->pid == p->tgid;
1414}
1415
Ingo Molnar36c8b582006-07-03 00:25:41 -07001416static inline struct task_struct *next_thread(const struct task_struct *p)
Oleg Nesterov47e65322006-03-28 16:11:25 -08001417{
1418 return list_entry(rcu_dereference(p->thread_group.next),
Ingo Molnar36c8b582006-07-03 00:25:41 -07001419 struct task_struct, thread_group);
Oleg Nesterov47e65322006-03-28 16:11:25 -08001420}
1421
Ingo Molnar36c8b582006-07-03 00:25:41 -07001422static inline int thread_group_empty(struct task_struct *p)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001423{
Oleg Nesterov47e65322006-03-28 16:11:25 -08001424 return list_empty(&p->thread_group);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001425}
1426
1427#define delay_group_leader(p) \
1428 (thread_group_leader(p) && !thread_group_empty(p))
1429
Linus Torvalds1da177e2005-04-16 15:20:36 -07001430/*
Eric W. Biederman260ea102006-06-23 02:05:18 -07001431 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
Jens Axboe22e2c502005-06-27 10:55:12 +02001432 * subscriptions and synchronises with wait4(). Also used in procfs. Also
Paul Jackson053199e2005-10-30 15:02:30 -08001433 * pins the final release of task.io_context. Also protects ->cpuset.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001434 *
1435 * Nests both inside and outside of read_lock(&tasklist_lock).
1436 * It must not be nested with write_lock_irq(&tasklist_lock),
1437 * neither inside nor outside.
1438 */
1439static inline void task_lock(struct task_struct *p)
1440{
1441 spin_lock(&p->alloc_lock);
1442}
1443
1444static inline void task_unlock(struct task_struct *p)
1445{
1446 spin_unlock(&p->alloc_lock);
1447}
1448
Oleg Nesterovf63ee722006-03-28 16:11:13 -08001449extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
1450 unsigned long *flags);
1451
1452static inline void unlock_task_sighand(struct task_struct *tsk,
1453 unsigned long *flags)
1454{
1455 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
1456}
1457
Al Virof0373602005-11-13 16:06:57 -08001458#ifndef __HAVE_THREAD_FUNCTIONS
1459
Al Viroa1261f52005-11-13 16:06:55 -08001460#define task_thread_info(task) (task)->thread_info
Al Viro9fc65872006-01-12 01:05:34 -08001461#define task_stack_page(task) ((void*)((task)->thread_info))
Al Viroa1261f52005-11-13 16:06:55 -08001462
Al Viro10ebffd2005-11-13 16:06:56 -08001463static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
1464{
1465 *task_thread_info(p) = *task_thread_info(org);
1466 task_thread_info(p)->task = p;
1467}
1468
1469static inline unsigned long *end_of_stack(struct task_struct *p)
1470{
1471 return (unsigned long *)(p->thread_info + 1);
1472}
1473
Al Virof0373602005-11-13 16:06:57 -08001474#endif
1475
Linus Torvalds1da177e2005-04-16 15:20:36 -07001476/* set thread flags in other task's structures
1477 * - see asm/thread_info.h for TIF_xxxx flags available
1478 */
1479static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1480{
Al Viroa1261f52005-11-13 16:06:55 -08001481 set_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001482}
1483
1484static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1485{
Al Viroa1261f52005-11-13 16:06:55 -08001486 clear_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001487}
1488
1489static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1490{
Al Viroa1261f52005-11-13 16:06:55 -08001491 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001492}
1493
1494static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1495{
Al Viroa1261f52005-11-13 16:06:55 -08001496 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001497}
1498
1499static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1500{
Al Viroa1261f52005-11-13 16:06:55 -08001501 return test_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001502}
1503
1504static inline void set_tsk_need_resched(struct task_struct *tsk)
1505{
1506 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1507}
1508
1509static inline void clear_tsk_need_resched(struct task_struct *tsk)
1510{
1511 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1512}
1513
1514static inline int signal_pending(struct task_struct *p)
1515{
1516 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1517}
1518
1519static inline int need_resched(void)
1520{
1521 return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1522}
1523
1524/*
1525 * cond_resched() and cond_resched_lock(): latency reduction via
1526 * explicit rescheduling in places that are safe. The return
1527 * value indicates whether a reschedule was done in fact.
1528 * cond_resched_lock() will drop the spinlock before scheduling,
1529 * cond_resched_softirq() will enable bhs before scheduling.
1530 */
1531extern int cond_resched(void);
1532extern int cond_resched_lock(spinlock_t * lock);
1533extern int cond_resched_softirq(void);
1534
1535/*
1536 * Does a critical section need to be broken due to another
1537 * task waiting?:
1538 */
1539#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
1540# define need_lockbreak(lock) ((lock)->break_lock)
1541#else
1542# define need_lockbreak(lock) 0
1543#endif
1544
1545/*
1546 * Does a critical section need to be broken due to another
1547 * task waiting or preemption being signalled:
1548 */
1549static inline int lock_need_resched(spinlock_t *lock)
1550{
1551 if (need_lockbreak(lock) || need_resched())
1552 return 1;
1553 return 0;
1554}
1555
1556/* Reevaluate whether the task has signals pending delivery.
1557 This is required every time the blocked sigset_t changes.
1558 callers must hold sighand->siglock. */
1559
1560extern FASTCALL(void recalc_sigpending_tsk(struct task_struct *t));
1561extern void recalc_sigpending(void);
1562
1563extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1564
1565/*
1566 * Wrappers for p->thread_info->cpu access. No-op on UP.
1567 */
1568#ifdef CONFIG_SMP
1569
1570static inline unsigned int task_cpu(const struct task_struct *p)
1571{
Al Viroa1261f52005-11-13 16:06:55 -08001572 return task_thread_info(p)->cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001573}
1574
1575static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1576{
Al Viroa1261f52005-11-13 16:06:55 -08001577 task_thread_info(p)->cpu = cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001578}
1579
1580#else
1581
1582static inline unsigned int task_cpu(const struct task_struct *p)
1583{
1584 return 0;
1585}
1586
1587static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1588{
1589}
1590
1591#endif /* CONFIG_SMP */
1592
1593#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1594extern void arch_pick_mmap_layout(struct mm_struct *mm);
1595#else
1596static inline void arch_pick_mmap_layout(struct mm_struct *mm)
1597{
1598 mm->mmap_base = TASK_UNMAPPED_BASE;
1599 mm->get_unmapped_area = arch_get_unmapped_area;
1600 mm->unmap_area = arch_unmap_area;
1601}
1602#endif
1603
1604extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
1605extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
1606
Siddha, Suresh B5c45bf22006-06-27 02:54:42 -07001607#include <linux/sysdev.h>
1608extern int sched_mc_power_savings, sched_smt_power_savings;
1609extern struct sysdev_attribute attr_sched_mc_power_savings, attr_sched_smt_power_savings;
1610extern int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls);
1611
Linus Torvalds1da177e2005-04-16 15:20:36 -07001612extern void normalize_rt_tasks(void);
1613
Linus Torvalds1da177e2005-04-16 15:20:36 -07001614#ifdef CONFIG_PM
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001615/*
1616 * Check if a process has been frozen
1617 */
1618static inline int frozen(struct task_struct *p)
1619{
1620 return p->flags & PF_FROZEN;
1621}
1622
1623/*
1624 * Check if there is a request to freeze a process
1625 */
1626static inline int freezing(struct task_struct *p)
1627{
1628 return p->flags & PF_FREEZE;
1629}
1630
1631/*
1632 * Request that a process be frozen
1633 * FIXME: SMP problem. We may not modify other process' flags!
1634 */
1635static inline void freeze(struct task_struct *p)
1636{
1637 p->flags |= PF_FREEZE;
1638}
1639
1640/*
Rafael J. Wysockia7ef7872006-08-05 12:13:42 -07001641 * Sometimes we may need to cancel the previous 'freeze' request
1642 */
1643static inline void do_not_freeze(struct task_struct *p)
1644{
1645 p->flags &= ~PF_FREEZE;
1646}
1647
1648/*
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001649 * Wake up a frozen process
1650 */
1651static inline int thaw_process(struct task_struct *p)
1652{
1653 if (frozen(p)) {
1654 p->flags &= ~PF_FROZEN;
1655 wake_up_process(p);
1656 return 1;
1657 }
1658 return 0;
1659}
1660
1661/*
1662 * freezing is complete, mark process as frozen
1663 */
1664static inline void frozen_process(struct task_struct *p)
1665{
1666 p->flags = (p->flags & ~PF_FREEZE) | PF_FROZEN;
1667}
1668
1669extern void refrigerator(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001670extern int freeze_processes(void);
1671extern void thaw_processes(void);
1672
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001673static inline int try_to_freeze(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001674{
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001675 if (freezing(current)) {
1676 refrigerator();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001677 return 1;
1678 } else
1679 return 0;
1680}
1681#else
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001682static inline int frozen(struct task_struct *p) { return 0; }
1683static inline int freezing(struct task_struct *p) { return 0; }
1684static inline void freeze(struct task_struct *p) { BUG(); }
1685static inline int thaw_process(struct task_struct *p) { return 1; }
1686static inline void frozen_process(struct task_struct *p) { BUG(); }
1687
1688static inline void refrigerator(void) {}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001689static inline int freeze_processes(void) { BUG(); return 0; }
1690static inline void thaw_processes(void) {}
1691
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001692static inline int try_to_freeze(void) { return 0; }
1693
Linus Torvalds1da177e2005-04-16 15:20:36 -07001694#endif /* CONFIG_PM */
1695#endif /* __KERNEL__ */
1696
1697#endif