7e0ff5dba986cf19daeadadaf0cc7fa985d7aaf6
[deliverable/linux.git] / include / linux / sched.h
1 #ifndef _LINUX_SCHED_H
2 #define _LINUX_SCHED_H
3
4 #include <asm/param.h> /* for HZ */
5
6 #include <linux/config.h>
7 #include <linux/capability.h>
8 #include <linux/threads.h>
9 #include <linux/kernel.h>
10 #include <linux/types.h>
11 #include <linux/timex.h>
12 #include <linux/jiffies.h>
13 #include <linux/rbtree.h>
14 #include <linux/thread_info.h>
15 #include <linux/cpumask.h>
16 #include <linux/errno.h>
17 #include <linux/nodemask.h>
18
19 #include <asm/system.h>
20 #include <asm/semaphore.h>
21 #include <asm/page.h>
22 #include <asm/ptrace.h>
23 #include <asm/mmu.h>
24 #include <asm/cputime.h>
25
26 #include <linux/smp.h>
27 #include <linux/sem.h>
28 #include <linux/signal.h>
29 #include <linux/securebits.h>
30 #include <linux/fs_struct.h>
31 #include <linux/compiler.h>
32 #include <linux/completion.h>
33 #include <linux/pid.h>
34 #include <linux/percpu.h>
35 #include <linux/topology.h>
36 #include <linux/seccomp.h>
37 #include <linux/rcupdate.h>
38 #include <linux/futex.h>
39
40 #include <linux/auxvec.h> /* For AT_VECTOR_SIZE */
41
42 struct exec_domain;
43
44 /*
45 * cloning flags:
46 */
47 #define CSIGNAL 0x000000ff /* signal mask to be sent at exit */
48 #define CLONE_VM 0x00000100 /* set if VM shared between processes */
49 #define CLONE_FS 0x00000200 /* set if fs info shared between processes */
50 #define CLONE_FILES 0x00000400 /* set if open files shared between processes */
51 #define CLONE_SIGHAND 0x00000800 /* set if signal handlers and blocked signals shared */
52 #define CLONE_PTRACE 0x00002000 /* set if we want to let tracing continue on the child too */
53 #define CLONE_VFORK 0x00004000 /* set if the parent wants the child to wake it up on mm_release */
54 #define CLONE_PARENT 0x00008000 /* set if we want to have the same parent as the cloner */
55 #define CLONE_THREAD 0x00010000 /* Same thread group? */
56 #define CLONE_NEWNS 0x00020000 /* New namespace group? */
57 #define CLONE_SYSVSEM 0x00040000 /* share system V SEM_UNDO semantics */
58 #define CLONE_SETTLS 0x00080000 /* create a new TLS for the child */
59 #define CLONE_PARENT_SETTID 0x00100000 /* set the TID in the parent */
60 #define CLONE_CHILD_CLEARTID 0x00200000 /* clear the TID in the child */
61 #define CLONE_DETACHED 0x00400000 /* Unused, ignored */
62 #define CLONE_UNTRACED 0x00800000 /* set if the tracing process can't force CLONE_PTRACE on this clone */
63 #define CLONE_CHILD_SETTID 0x01000000 /* set the TID in the child */
64 #define CLONE_STOPPED 0x02000000 /* Start in stopped state */
65
66 /*
67 * List of flags we want to share for kernel threads,
68 * if only because they are not used by them anyway.
69 */
70 #define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
71
72 /*
73 * These are the constant used to fake the fixed-point load-average
74 * counting. Some notes:
75 * - 11 bit fractions expand to 22 bits by the multiplies: this gives
76 * a load-average precision of 10 bits integer + 11 bits fractional
77 * - if you want to count load-averages more often, you need more
78 * precision, or rounding will get you. With 2-second counting freq,
79 * the EXP_n values would be 1981, 2034 and 2043 if still using only
80 * 11 bit fractions.
81 */
82 extern unsigned long avenrun[]; /* Load averages */
83
84 #define FSHIFT 11 /* nr of bits of precision */
85 #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
86 #define LOAD_FREQ (5*HZ) /* 5 sec intervals */
87 #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
88 #define EXP_5 2014 /* 1/exp(5sec/5min) */
89 #define EXP_15 2037 /* 1/exp(5sec/15min) */
90
91 #define CALC_LOAD(load,exp,n) \
92 load *= exp; \
93 load += n*(FIXED_1-exp); \
94 load >>= FSHIFT;
95
96 extern unsigned long total_forks;
97 extern int nr_threads;
98 extern int last_pid;
99 DECLARE_PER_CPU(unsigned long, process_counts);
100 extern int nr_processes(void);
101 extern unsigned long nr_running(void);
102 extern unsigned long nr_uninterruptible(void);
103 extern unsigned long nr_active(void);
104 extern unsigned long nr_iowait(void);
105
106 #include <linux/time.h>
107 #include <linux/param.h>
108 #include <linux/resource.h>
109 #include <linux/timer.h>
110 #include <linux/hrtimer.h>
111
112 #include <asm/processor.h>
113
114 /*
115 * Task state bitmask. NOTE! These bits are also
116 * encoded in fs/proc/array.c: get_task_state().
117 *
118 * We have two separate sets of flags: task->state
119 * is about runnability, while task->exit_state are
120 * about the task exiting. Confusing, but this way
121 * modifying one set can't modify the other one by
122 * mistake.
123 */
124 #define TASK_RUNNING 0
125 #define TASK_INTERRUPTIBLE 1
126 #define TASK_UNINTERRUPTIBLE 2
127 #define TASK_STOPPED 4
128 #define TASK_TRACED 8
129 /* in tsk->exit_state */
130 #define EXIT_ZOMBIE 16
131 #define EXIT_DEAD 32
132 /* in tsk->state again */
133 #define TASK_NONINTERACTIVE 64
134
135 #define __set_task_state(tsk, state_value) \
136 do { (tsk)->state = (state_value); } while (0)
137 #define set_task_state(tsk, state_value) \
138 set_mb((tsk)->state, (state_value))
139
140 /*
141 * set_current_state() includes a barrier so that the write of current->state
142 * is correctly serialised wrt the caller's subsequent test of whether to
143 * actually sleep:
144 *
145 * set_current_state(TASK_UNINTERRUPTIBLE);
146 * if (do_i_need_to_sleep())
147 * schedule();
148 *
149 * If the caller does not need such serialisation then use __set_current_state()
150 */
151 #define __set_current_state(state_value) \
152 do { current->state = (state_value); } while (0)
153 #define set_current_state(state_value) \
154 set_mb(current->state, (state_value))
155
156 /* Task command name length */
157 #define TASK_COMM_LEN 16
158
159 /*
160 * Scheduling policies
161 */
162 #define SCHED_NORMAL 0
163 #define SCHED_FIFO 1
164 #define SCHED_RR 2
165 #define SCHED_BATCH 3
166
167 struct sched_param {
168 int sched_priority;
169 };
170
171 #ifdef __KERNEL__
172
173 #include <linux/spinlock.h>
174
175 /*
176 * This serializes "schedule()" and also protects
177 * the run-queue from deletions/modifications (but
178 * _adding_ to the beginning of the run-queue has
179 * a separate lock).
180 */
181 extern rwlock_t tasklist_lock;
182 extern spinlock_t mmlist_lock;
183
184 typedef struct task_struct task_t;
185
186 extern void sched_init(void);
187 extern void sched_init_smp(void);
188 extern void init_idle(task_t *idle, int cpu);
189
190 extern cpumask_t nohz_cpu_mask;
191
192 extern void show_state(void);
193 extern void show_regs(struct pt_regs *);
194
195 /*
196 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
197 * task), SP is the stack pointer of the first frame that should be shown in the back
198 * trace (or NULL if the entire call-chain of the task should be shown).
199 */
200 extern void show_stack(struct task_struct *task, unsigned long *sp);
201
202 void io_schedule(void);
203 long io_schedule_timeout(long timeout);
204
205 extern void cpu_init (void);
206 extern void trap_init(void);
207 extern void update_process_times(int user);
208 extern void scheduler_tick(void);
209
210 #ifdef CONFIG_DETECT_SOFTLOCKUP
211 extern void softlockup_tick(void);
212 extern void spawn_softlockup_task(void);
213 extern void touch_softlockup_watchdog(void);
214 #else
215 static inline void softlockup_tick(void)
216 {
217 }
218 static inline void spawn_softlockup_task(void)
219 {
220 }
221 static inline void touch_softlockup_watchdog(void)
222 {
223 }
224 #endif
225
226
227 /* Attach to any functions which should be ignored in wchan output. */
228 #define __sched __attribute__((__section__(".sched.text")))
229 /* Is this address in the __sched functions? */
230 extern int in_sched_functions(unsigned long addr);
231
232 #define MAX_SCHEDULE_TIMEOUT LONG_MAX
233 extern signed long FASTCALL(schedule_timeout(signed long timeout));
234 extern signed long schedule_timeout_interruptible(signed long timeout);
235 extern signed long schedule_timeout_uninterruptible(signed long timeout);
236 asmlinkage void schedule(void);
237
238 struct namespace;
239
240 /* Maximum number of active map areas.. This is a random (large) number */
241 #define DEFAULT_MAX_MAP_COUNT 65536
242
243 extern int sysctl_max_map_count;
244
245 #include <linux/aio.h>
246
247 extern unsigned long
248 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
249 unsigned long, unsigned long);
250 extern unsigned long
251 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
252 unsigned long len, unsigned long pgoff,
253 unsigned long flags);
254 extern void arch_unmap_area(struct mm_struct *, unsigned long);
255 extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
256
257 #if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
258 /*
259 * The mm counters are not protected by its page_table_lock,
260 * so must be incremented atomically.
261 */
262 #define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
263 #define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
264 #define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
265 #define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
266 #define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
267 typedef atomic_long_t mm_counter_t;
268
269 #else /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
270 /*
271 * The mm counters are protected by its page_table_lock,
272 * so can be incremented directly.
273 */
274 #define set_mm_counter(mm, member, value) (mm)->_##member = (value)
275 #define get_mm_counter(mm, member) ((mm)->_##member)
276 #define add_mm_counter(mm, member, value) (mm)->_##member += (value)
277 #define inc_mm_counter(mm, member) (mm)->_##member++
278 #define dec_mm_counter(mm, member) (mm)->_##member--
279 typedef unsigned long mm_counter_t;
280
281 #endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
282
283 #define get_mm_rss(mm) \
284 (get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
285 #define update_hiwater_rss(mm) do { \
286 unsigned long _rss = get_mm_rss(mm); \
287 if ((mm)->hiwater_rss < _rss) \
288 (mm)->hiwater_rss = _rss; \
289 } while (0)
290 #define update_hiwater_vm(mm) do { \
291 if ((mm)->hiwater_vm < (mm)->total_vm) \
292 (mm)->hiwater_vm = (mm)->total_vm; \
293 } while (0)
294
295 struct mm_struct {
296 struct vm_area_struct * mmap; /* list of VMAs */
297 struct rb_root mm_rb;
298 struct vm_area_struct * mmap_cache; /* last find_vma result */
299 unsigned long (*get_unmapped_area) (struct file *filp,
300 unsigned long addr, unsigned long len,
301 unsigned long pgoff, unsigned long flags);
302 void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
303 unsigned long mmap_base; /* base of mmap area */
304 unsigned long task_size; /* size of task vm space */
305 unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */
306 unsigned long free_area_cache; /* first hole of size cached_hole_size or larger */
307 pgd_t * pgd;
308 atomic_t mm_users; /* How many users with user space? */
309 atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */
310 int map_count; /* number of VMAs */
311 struct rw_semaphore mmap_sem;
312 spinlock_t page_table_lock; /* Protects page tables and some counters */
313
314 struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung
315 * together off init_mm.mmlist, and are protected
316 * by mmlist_lock
317 */
318
319 /* Special counters, in some configurations protected by the
320 * page_table_lock, in other configurations by being atomic.
321 */
322 mm_counter_t _file_rss;
323 mm_counter_t _anon_rss;
324
325 unsigned long hiwater_rss; /* High-watermark of RSS usage */
326 unsigned long hiwater_vm; /* High-water virtual memory usage */
327
328 unsigned long total_vm, locked_vm, shared_vm, exec_vm;
329 unsigned long stack_vm, reserved_vm, def_flags, nr_ptes;
330 unsigned long start_code, end_code, start_data, end_data;
331 unsigned long start_brk, brk, start_stack;
332 unsigned long arg_start, arg_end, env_start, env_end;
333
334 unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
335
336 unsigned dumpable:2;
337 cpumask_t cpu_vm_mask;
338
339 /* Architecture-specific MM context */
340 mm_context_t context;
341
342 /* Token based thrashing protection. */
343 unsigned long swap_token_time;
344 char recent_pagein;
345
346 /* coredumping support */
347 int core_waiters;
348 struct completion *core_startup_done, core_done;
349
350 /* aio bits */
351 rwlock_t ioctx_list_lock;
352 struct kioctx *ioctx_list;
353 };
354
355 struct sighand_struct {
356 atomic_t count;
357 struct k_sigaction action[_NSIG];
358 spinlock_t siglock;
359 };
360
361 /*
362 * NOTE! "signal_struct" does not have it's own
363 * locking, because a shared signal_struct always
364 * implies a shared sighand_struct, so locking
365 * sighand_struct is always a proper superset of
366 * the locking of signal_struct.
367 */
368 struct signal_struct {
369 atomic_t count;
370 atomic_t live;
371
372 wait_queue_head_t wait_chldexit; /* for wait4() */
373
374 /* current thread group signal load-balancing target: */
375 task_t *curr_target;
376
377 /* shared signal handling: */
378 struct sigpending shared_pending;
379
380 /* thread group exit support */
381 int group_exit_code;
382 /* overloaded:
383 * - notify group_exit_task when ->count is equal to notify_count
384 * - everyone except group_exit_task is stopped during signal delivery
385 * of fatal signals, group_exit_task processes the signal.
386 */
387 struct task_struct *group_exit_task;
388 int notify_count;
389
390 /* thread group stop support, overloads group_exit_code too */
391 int group_stop_count;
392 unsigned int flags; /* see SIGNAL_* flags below */
393
394 /* POSIX.1b Interval Timers */
395 struct list_head posix_timers;
396
397 /* ITIMER_REAL timer for the process */
398 struct hrtimer real_timer;
399 struct task_struct *tsk;
400 ktime_t it_real_incr;
401
402 /* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
403 cputime_t it_prof_expires, it_virt_expires;
404 cputime_t it_prof_incr, it_virt_incr;
405
406 /* job control IDs */
407 pid_t pgrp;
408 pid_t tty_old_pgrp;
409 pid_t session;
410 /* boolean value for session group leader */
411 int leader;
412
413 struct tty_struct *tty; /* NULL if no tty */
414
415 /*
416 * Cumulative resource counters for dead threads in the group,
417 * and for reaped dead child processes forked by this group.
418 * Live threads maintain their own counters and add to these
419 * in __exit_signal, except for the group leader.
420 */
421 cputime_t utime, stime, cutime, cstime;
422 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
423 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
424
425 /*
426 * Cumulative ns of scheduled CPU time for dead threads in the
427 * group, not including a zombie group leader. (This only differs
428 * from jiffies_to_ns(utime + stime) if sched_clock uses something
429 * other than jiffies.)
430 */
431 unsigned long long sched_time;
432
433 /*
434 * We don't bother to synchronize most readers of this at all,
435 * because there is no reader checking a limit that actually needs
436 * to get both rlim_cur and rlim_max atomically, and either one
437 * alone is a single word that can safely be read normally.
438 * getrlimit/setrlimit use task_lock(current->group_leader) to
439 * protect this instead of the siglock, because they really
440 * have no need to disable irqs.
441 */
442 struct rlimit rlim[RLIM_NLIMITS];
443
444 struct list_head cpu_timers[3];
445
446 /* keep the process-shared keyrings here so that they do the right
447 * thing in threads created with CLONE_THREAD */
448 #ifdef CONFIG_KEYS
449 struct key *session_keyring; /* keyring inherited over fork */
450 struct key *process_keyring; /* keyring private to this process */
451 #endif
452 };
453
454 /* Context switch must be unlocked if interrupts are to be enabled */
455 #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
456 # define __ARCH_WANT_UNLOCKED_CTXSW
457 #endif
458
459 /*
460 * Bits in flags field of signal_struct.
461 */
462 #define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */
463 #define SIGNAL_STOP_DEQUEUED 0x00000002 /* stop signal dequeued */
464 #define SIGNAL_STOP_CONTINUED 0x00000004 /* SIGCONT since WCONTINUED reap */
465 #define SIGNAL_GROUP_EXIT 0x00000008 /* group exit in progress */
466
467
468 /*
469 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
470 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
471 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
472 * values are inverted: lower p->prio value means higher priority.
473 *
474 * The MAX_USER_RT_PRIO value allows the actual maximum
475 * RT priority to be separate from the value exported to
476 * user-space. This allows kernel threads to set their
477 * priority to a value higher than any user task. Note:
478 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
479 */
480
481 #define MAX_USER_RT_PRIO 100
482 #define MAX_RT_PRIO MAX_USER_RT_PRIO
483
484 #define MAX_PRIO (MAX_RT_PRIO + 40)
485
486 #define rt_task(p) (unlikely((p)->prio < MAX_RT_PRIO))
487 #define batch_task(p) (unlikely((p)->policy == SCHED_BATCH))
488
489 /*
490 * Some day this will be a full-fledged user tracking system..
491 */
492 struct user_struct {
493 atomic_t __count; /* reference count */
494 atomic_t processes; /* How many processes does this user have? */
495 atomic_t files; /* How many open files does this user have? */
496 atomic_t sigpending; /* How many pending signals does this user have? */
497 #ifdef CONFIG_INOTIFY
498 atomic_t inotify_watches; /* How many inotify watches does this user have? */
499 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */
500 #endif
501 /* protected by mq_lock */
502 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
503 unsigned long locked_shm; /* How many pages of mlocked shm ? */
504
505 #ifdef CONFIG_KEYS
506 struct key *uid_keyring; /* UID specific keyring */
507 struct key *session_keyring; /* UID's default session keyring */
508 #endif
509
510 /* Hash table maintenance information */
511 struct list_head uidhash_list;
512 uid_t uid;
513 };
514
515 extern struct user_struct *find_user(uid_t);
516
517 extern struct user_struct root_user;
518 #define INIT_USER (&root_user)
519
520 typedef struct prio_array prio_array_t;
521 struct backing_dev_info;
522 struct reclaim_state;
523
524 #ifdef CONFIG_SCHEDSTATS
525 struct sched_info {
526 /* cumulative counters */
527 unsigned long cpu_time, /* time spent on the cpu */
528 run_delay, /* time spent waiting on a runqueue */
529 pcnt; /* # of timeslices run on this cpu */
530
531 /* timestamps */
532 unsigned long last_arrival, /* when we last ran on a cpu */
533 last_queued; /* when we were last queued to run */
534 };
535
536 extern struct file_operations proc_schedstat_operations;
537 #endif
538
539 enum idle_type
540 {
541 SCHED_IDLE,
542 NOT_IDLE,
543 NEWLY_IDLE,
544 MAX_IDLE_TYPES
545 };
546
547 /*
548 * sched-domains (multiprocessor balancing) declarations:
549 */
550 #ifdef CONFIG_SMP
551 #define SCHED_LOAD_SCALE 128UL /* increase resolution of load */
552
553 #define SD_LOAD_BALANCE 1 /* Do load balancing on this domain. */
554 #define SD_BALANCE_NEWIDLE 2 /* Balance when about to become idle */
555 #define SD_BALANCE_EXEC 4 /* Balance on exec */
556 #define SD_BALANCE_FORK 8 /* Balance on fork, clone */
557 #define SD_WAKE_IDLE 16 /* Wake to idle CPU on task wakeup */
558 #define SD_WAKE_AFFINE 32 /* Wake task to waking CPU */
559 #define SD_WAKE_BALANCE 64 /* Perform balancing at task wakeup */
560 #define SD_SHARE_CPUPOWER 128 /* Domain members share cpu power */
561
562 struct sched_group {
563 struct sched_group *next; /* Must be a circular list */
564 cpumask_t cpumask;
565
566 /*
567 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
568 * single CPU. This is read only (except for setup, hotplug CPU).
569 */
570 unsigned long cpu_power;
571 };
572
573 struct sched_domain {
574 /* These fields must be setup */
575 struct sched_domain *parent; /* top domain must be null terminated */
576 struct sched_group *groups; /* the balancing groups of the domain */
577 cpumask_t span; /* span of all CPUs in this domain */
578 unsigned long min_interval; /* Minimum balance interval ms */
579 unsigned long max_interval; /* Maximum balance interval ms */
580 unsigned int busy_factor; /* less balancing by factor if busy */
581 unsigned int imbalance_pct; /* No balance until over watermark */
582 unsigned long long cache_hot_time; /* Task considered cache hot (ns) */
583 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */
584 unsigned int per_cpu_gain; /* CPU % gained by adding domain cpus */
585 unsigned int busy_idx;
586 unsigned int idle_idx;
587 unsigned int newidle_idx;
588 unsigned int wake_idx;
589 unsigned int forkexec_idx;
590 int flags; /* See SD_* */
591
592 /* Runtime fields. */
593 unsigned long last_balance; /* init to jiffies. units in jiffies */
594 unsigned int balance_interval; /* initialise to 1. units in ms. */
595 unsigned int nr_balance_failed; /* initialise to 0 */
596
597 #ifdef CONFIG_SCHEDSTATS
598 /* load_balance() stats */
599 unsigned long lb_cnt[MAX_IDLE_TYPES];
600 unsigned long lb_failed[MAX_IDLE_TYPES];
601 unsigned long lb_balanced[MAX_IDLE_TYPES];
602 unsigned long lb_imbalance[MAX_IDLE_TYPES];
603 unsigned long lb_gained[MAX_IDLE_TYPES];
604 unsigned long lb_hot_gained[MAX_IDLE_TYPES];
605 unsigned long lb_nobusyg[MAX_IDLE_TYPES];
606 unsigned long lb_nobusyq[MAX_IDLE_TYPES];
607
608 /* Active load balancing */
609 unsigned long alb_cnt;
610 unsigned long alb_failed;
611 unsigned long alb_pushed;
612
613 /* SD_BALANCE_EXEC stats */
614 unsigned long sbe_cnt;
615 unsigned long sbe_balanced;
616 unsigned long sbe_pushed;
617
618 /* SD_BALANCE_FORK stats */
619 unsigned long sbf_cnt;
620 unsigned long sbf_balanced;
621 unsigned long sbf_pushed;
622
623 /* try_to_wake_up() stats */
624 unsigned long ttwu_wake_remote;
625 unsigned long ttwu_move_affine;
626 unsigned long ttwu_move_balance;
627 #endif
628 };
629
630 extern void partition_sched_domains(cpumask_t *partition1,
631 cpumask_t *partition2);
632
633 /*
634 * Maximum cache size the migration-costs auto-tuning code will
635 * search from:
636 */
637 extern unsigned int max_cache_size;
638
639 #endif /* CONFIG_SMP */
640
641
642 struct io_context; /* See blkdev.h */
643 void exit_io_context(void);
644 struct cpuset;
645
646 #define NGROUPS_SMALL 32
647 #define NGROUPS_PER_BLOCK ((int)(PAGE_SIZE / sizeof(gid_t)))
648 struct group_info {
649 int ngroups;
650 atomic_t usage;
651 gid_t small_block[NGROUPS_SMALL];
652 int nblocks;
653 gid_t *blocks[0];
654 };
655
656 /*
657 * get_group_info() must be called with the owning task locked (via task_lock())
658 * when task != current. The reason being that the vast majority of callers are
659 * looking at current->group_info, which can not be changed except by the
660 * current task. Changing current->group_info requires the task lock, too.
661 */
662 #define get_group_info(group_info) do { \
663 atomic_inc(&(group_info)->usage); \
664 } while (0)
665
666 #define put_group_info(group_info) do { \
667 if (atomic_dec_and_test(&(group_info)->usage)) \
668 groups_free(group_info); \
669 } while (0)
670
671 extern struct group_info *groups_alloc(int gidsetsize);
672 extern void groups_free(struct group_info *group_info);
673 extern int set_current_groups(struct group_info *group_info);
674 extern int groups_search(struct group_info *group_info, gid_t grp);
675 /* access the groups "array" with this macro */
676 #define GROUP_AT(gi, i) \
677 ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
678
679 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
680 extern void prefetch_stack(struct task_struct*);
681 #else
682 static inline void prefetch_stack(struct task_struct *t) { }
683 #endif
684
685 struct audit_context; /* See audit.c */
686 struct mempolicy;
687
688 enum sleep_type {
689 SLEEP_NORMAL,
690 SLEEP_NONINTERACTIVE,
691 SLEEP_INTERACTIVE,
692 SLEEP_INTERRUPTED,
693 };
694
695 struct task_struct {
696 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
697 struct thread_info *thread_info;
698 atomic_t usage;
699 unsigned long flags; /* per process flags, defined below */
700 unsigned long ptrace;
701
702 int lock_depth; /* BKL lock depth */
703
704 #if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW)
705 int oncpu;
706 #endif
707 int prio, static_prio;
708 struct list_head run_list;
709 prio_array_t *array;
710
711 unsigned short ioprio;
712 unsigned int btrace_seq;
713
714 unsigned long sleep_avg;
715 unsigned long long timestamp, last_ran;
716 unsigned long long sched_time; /* sched_clock time spent running */
717 enum sleep_type sleep_type;
718
719 unsigned long policy;
720 cpumask_t cpus_allowed;
721 unsigned int time_slice, first_time_slice;
722
723 #ifdef CONFIG_SCHEDSTATS
724 struct sched_info sched_info;
725 #endif
726
727 struct list_head tasks;
728 /*
729 * ptrace_list/ptrace_children forms the list of my children
730 * that were stolen by a ptracer.
731 */
732 struct list_head ptrace_children;
733 struct list_head ptrace_list;
734
735 struct mm_struct *mm, *active_mm;
736
737 /* task state */
738 struct linux_binfmt *binfmt;
739 long exit_state;
740 int exit_code, exit_signal;
741 int pdeath_signal; /* The signal sent when the parent dies */
742 /* ??? */
743 unsigned long personality;
744 unsigned did_exec:1;
745 pid_t pid;
746 pid_t tgid;
747 /*
748 * pointers to (original) parent process, youngest child, younger sibling,
749 * older sibling, respectively. (p->father can be replaced with
750 * p->parent->pid)
751 */
752 struct task_struct *real_parent; /* real parent process (when being debugged) */
753 struct task_struct *parent; /* parent process */
754 /*
755 * children/sibling forms the list of my children plus the
756 * tasks I'm ptracing.
757 */
758 struct list_head children; /* list of my children */
759 struct list_head sibling; /* linkage in my parent's children list */
760 struct task_struct *group_leader; /* threadgroup leader */
761
762 /* PID/PID hash table linkage. */
763 struct pid pids[PIDTYPE_MAX];
764 struct list_head thread_group;
765
766 struct completion *vfork_done; /* for vfork() */
767 int __user *set_child_tid; /* CLONE_CHILD_SETTID */
768 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
769
770 unsigned long rt_priority;
771 cputime_t utime, stime;
772 unsigned long nvcsw, nivcsw; /* context switch counts */
773 struct timespec start_time;
774 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
775 unsigned long min_flt, maj_flt;
776
777 cputime_t it_prof_expires, it_virt_expires;
778 unsigned long long it_sched_expires;
779 struct list_head cpu_timers[3];
780
781 /* process credentials */
782 uid_t uid,euid,suid,fsuid;
783 gid_t gid,egid,sgid,fsgid;
784 struct group_info *group_info;
785 kernel_cap_t cap_effective, cap_inheritable, cap_permitted;
786 unsigned keep_capabilities:1;
787 struct user_struct *user;
788 #ifdef CONFIG_KEYS
789 struct key *request_key_auth; /* assumed request_key authority */
790 struct key *thread_keyring; /* keyring private to this thread */
791 unsigned char jit_keyring; /* default keyring to attach requested keys to */
792 #endif
793 int oomkilladj; /* OOM kill score adjustment (bit shift). */
794 char comm[TASK_COMM_LEN]; /* executable name excluding path
795 - access with [gs]et_task_comm (which lock
796 it with task_lock())
797 - initialized normally by flush_old_exec */
798 /* file system info */
799 int link_count, total_link_count;
800 /* ipc stuff */
801 struct sysv_sem sysvsem;
802 /* CPU-specific state of this task */
803 struct thread_struct thread;
804 /* filesystem information */
805 struct fs_struct *fs;
806 /* open file information */
807 struct files_struct *files;
808 /* namespace */
809 struct namespace *namespace;
810 /* signal handlers */
811 struct signal_struct *signal;
812 struct sighand_struct *sighand;
813
814 sigset_t blocked, real_blocked;
815 sigset_t saved_sigmask; /* To be restored with TIF_RESTORE_SIGMASK */
816 struct sigpending pending;
817
818 unsigned long sas_ss_sp;
819 size_t sas_ss_size;
820 int (*notifier)(void *priv);
821 void *notifier_data;
822 sigset_t *notifier_mask;
823
824 void *security;
825 struct audit_context *audit_context;
826 seccomp_t seccomp;
827
828 /* Thread group tracking */
829 u32 parent_exec_id;
830 u32 self_exec_id;
831 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
832 spinlock_t alloc_lock;
833 /* Protection of proc_dentry: nesting proc_lock, dcache_lock, write_lock_irq(&tasklist_lock); */
834 spinlock_t proc_lock;
835
836 #ifdef CONFIG_DEBUG_MUTEXES
837 /* mutex deadlock detection */
838 struct mutex_waiter *blocked_on;
839 #endif
840
841 /* journalling filesystem info */
842 void *journal_info;
843
844 /* VM state */
845 struct reclaim_state *reclaim_state;
846
847 struct dentry *proc_dentry;
848 struct backing_dev_info *backing_dev_info;
849
850 struct io_context *io_context;
851
852 unsigned long ptrace_message;
853 siginfo_t *last_siginfo; /* For ptrace use. */
854 /*
855 * current io wait handle: wait queue entry to use for io waits
856 * If this thread is processing aio, this points at the waitqueue
857 * inside the currently handled kiocb. It may be NULL (i.e. default
858 * to a stack based synchronous wait) if its doing sync IO.
859 */
860 wait_queue_t *io_wait;
861 /* i/o counters(bytes read/written, #syscalls */
862 u64 rchar, wchar, syscr, syscw;
863 #if defined(CONFIG_BSD_PROCESS_ACCT)
864 u64 acct_rss_mem1; /* accumulated rss usage */
865 u64 acct_vm_mem1; /* accumulated virtual memory usage */
866 clock_t acct_stimexpd; /* clock_t-converted stime since last update */
867 #endif
868 #ifdef CONFIG_NUMA
869 struct mempolicy *mempolicy;
870 short il_next;
871 #endif
872 #ifdef CONFIG_CPUSETS
873 struct cpuset *cpuset;
874 nodemask_t mems_allowed;
875 int cpuset_mems_generation;
876 int cpuset_mem_spread_rotor;
877 #endif
878 struct robust_list_head __user *robust_list;
879 #ifdef CONFIG_COMPAT
880 struct compat_robust_list_head __user *compat_robust_list;
881 #endif
882
883 atomic_t fs_excl; /* holding fs exclusive resources */
884 struct rcu_head rcu;
885 };
886
887 static inline pid_t process_group(struct task_struct *tsk)
888 {
889 return tsk->signal->pgrp;
890 }
891
892 /**
893 * pid_alive - check that a task structure is not stale
894 * @p: Task structure to be checked.
895 *
896 * Test if a process is not yet dead (at most zombie state)
897 * If pid_alive fails, then pointers within the task structure
898 * can be stale and must not be dereferenced.
899 */
900 static inline int pid_alive(struct task_struct *p)
901 {
902 return p->pids[PIDTYPE_PID].nr != 0;
903 }
904
905 extern void free_task(struct task_struct *tsk);
906 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
907
908 extern void __put_task_struct_cb(struct rcu_head *rhp);
909 extern void __put_task_struct(struct task_struct *t);
910
911 static inline void put_task_struct(struct task_struct *t)
912 {
913 if (atomic_dec_and_test(&t->usage))
914 __put_task_struct(t);
915 }
916
917 /*
918 * Per process flags
919 */
920 #define PF_ALIGNWARN 0x00000001 /* Print alignment warning msgs */
921 /* Not implemented yet, only for 486*/
922 #define PF_STARTING 0x00000002 /* being created */
923 #define PF_EXITING 0x00000004 /* getting shut down */
924 #define PF_DEAD 0x00000008 /* Dead */
925 #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
926 #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
927 #define PF_DUMPCORE 0x00000200 /* dumped core */
928 #define PF_SIGNALED 0x00000400 /* killed by a signal */
929 #define PF_MEMALLOC 0x00000800 /* Allocating memory */
930 #define PF_FLUSHER 0x00001000 /* responsible for disk writeback */
931 #define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
932 #define PF_FREEZE 0x00004000 /* this task is being frozen for suspend now */
933 #define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
934 #define PF_FROZEN 0x00010000 /* frozen for system suspend */
935 #define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
936 #define PF_KSWAPD 0x00040000 /* I am kswapd */
937 #define PF_SWAPOFF 0x00080000 /* I am in swapoff */
938 #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
939 #define PF_SYNCWRITE 0x00200000 /* I am doing a sync write */
940 #define PF_BORROWED_MM 0x00400000 /* I am a kthread doing use_mm */
941 #define PF_RANDOMIZE 0x00800000 /* randomize virtual address space */
942 #define PF_SWAPWRITE 0x01000000 /* Allowed to write to swap */
943 #define PF_SPREAD_PAGE 0x04000000 /* Spread page cache over cpuset */
944 #define PF_SPREAD_SLAB 0x08000000 /* Spread some slab caches over cpuset */
945 #define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */
946
947 /*
948 * Only the _current_ task can read/write to tsk->flags, but other
949 * tasks can access tsk->flags in readonly mode for example
950 * with tsk_used_math (like during threaded core dumping).
951 * There is however an exception to this rule during ptrace
952 * or during fork: the ptracer task is allowed to write to the
953 * child->flags of its traced child (same goes for fork, the parent
954 * can write to the child->flags), because we're guaranteed the
955 * child is not running and in turn not changing child->flags
956 * at the same time the parent does it.
957 */
958 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
959 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
960 #define clear_used_math() clear_stopped_child_used_math(current)
961 #define set_used_math() set_stopped_child_used_math(current)
962 #define conditional_stopped_child_used_math(condition, child) \
963 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
964 #define conditional_used_math(condition) \
965 conditional_stopped_child_used_math(condition, current)
966 #define copy_to_stopped_child_used_math(child) \
967 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
968 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
969 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
970 #define used_math() tsk_used_math(current)
971
972 #ifdef CONFIG_SMP
973 extern int set_cpus_allowed(task_t *p, cpumask_t new_mask);
974 #else
975 static inline int set_cpus_allowed(task_t *p, cpumask_t new_mask)
976 {
977 if (!cpu_isset(0, new_mask))
978 return -EINVAL;
979 return 0;
980 }
981 #endif
982
983 extern unsigned long long sched_clock(void);
984 extern unsigned long long current_sched_time(const task_t *current_task);
985
986 /* sched_exec is called by processes performing an exec */
987 #ifdef CONFIG_SMP
988 extern void sched_exec(void);
989 #else
990 #define sched_exec() {}
991 #endif
992
993 #ifdef CONFIG_HOTPLUG_CPU
994 extern void idle_task_exit(void);
995 #else
996 static inline void idle_task_exit(void) {}
997 #endif
998
999 extern void sched_idle_next(void);
1000 extern void set_user_nice(task_t *p, long nice);
1001 extern int task_prio(const task_t *p);
1002 extern int task_nice(const task_t *p);
1003 extern int can_nice(const task_t *p, const int nice);
1004 extern int task_curr(const task_t *p);
1005 extern int idle_cpu(int cpu);
1006 extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1007 extern task_t *idle_task(int cpu);
1008 extern task_t *curr_task(int cpu);
1009 extern void set_curr_task(int cpu, task_t *p);
1010
1011 void yield(void);
1012
1013 /*
1014 * The default (Linux) execution domain.
1015 */
1016 extern struct exec_domain default_exec_domain;
1017
1018 union thread_union {
1019 struct thread_info thread_info;
1020 unsigned long stack[THREAD_SIZE/sizeof(long)];
1021 };
1022
1023 #ifndef __HAVE_ARCH_KSTACK_END
1024 static inline int kstack_end(void *addr)
1025 {
1026 /* Reliable end of stack detection:
1027 * Some APM bios versions misalign the stack
1028 */
1029 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1030 }
1031 #endif
1032
1033 extern union thread_union init_thread_union;
1034 extern struct task_struct init_task;
1035
1036 extern struct mm_struct init_mm;
1037
1038 #define find_task_by_pid(nr) find_task_by_pid_type(PIDTYPE_PID, nr)
1039 extern struct task_struct *find_task_by_pid_type(int type, int pid);
1040 extern void set_special_pids(pid_t session, pid_t pgrp);
1041 extern void __set_special_pids(pid_t session, pid_t pgrp);
1042
1043 /* per-UID process charging. */
1044 extern struct user_struct * alloc_uid(uid_t);
1045 static inline struct user_struct *get_uid(struct user_struct *u)
1046 {
1047 atomic_inc(&u->__count);
1048 return u;
1049 }
1050 extern void free_uid(struct user_struct *);
1051 extern void switch_uid(struct user_struct *);
1052
1053 #include <asm/current.h>
1054
1055 extern void do_timer(struct pt_regs *);
1056
1057 extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state));
1058 extern int FASTCALL(wake_up_process(struct task_struct * tsk));
1059 extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
1060 unsigned long clone_flags));
1061 #ifdef CONFIG_SMP
1062 extern void kick_process(struct task_struct *tsk);
1063 #else
1064 static inline void kick_process(struct task_struct *tsk) { }
1065 #endif
1066 extern void FASTCALL(sched_fork(task_t * p, int clone_flags));
1067 extern void FASTCALL(sched_exit(task_t * p));
1068
1069 extern int in_group_p(gid_t);
1070 extern int in_egroup_p(gid_t);
1071
1072 extern void proc_caches_init(void);
1073 extern void flush_signals(struct task_struct *);
1074 extern void flush_signal_handlers(struct task_struct *, int force_default);
1075 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1076
1077 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1078 {
1079 unsigned long flags;
1080 int ret;
1081
1082 spin_lock_irqsave(&tsk->sighand->siglock, flags);
1083 ret = dequeue_signal(tsk, mask, info);
1084 spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1085
1086 return ret;
1087 }
1088
1089 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1090 sigset_t *mask);
1091 extern void unblock_all_signals(void);
1092 extern void release_task(struct task_struct * p);
1093 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1094 extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
1095 extern int force_sigsegv(int, struct task_struct *);
1096 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1097 extern int __kill_pg_info(int sig, struct siginfo *info, pid_t pgrp);
1098 extern int kill_pg_info(int, struct siginfo *, pid_t);
1099 extern int kill_proc_info(int, struct siginfo *, pid_t);
1100 extern int kill_proc_info_as_uid(int, struct siginfo *, pid_t, uid_t, uid_t);
1101 extern void do_notify_parent(struct task_struct *, int);
1102 extern void force_sig(int, struct task_struct *);
1103 extern void force_sig_specific(int, struct task_struct *);
1104 extern int send_sig(int, struct task_struct *, int);
1105 extern void zap_other_threads(struct task_struct *p);
1106 extern int kill_pg(pid_t, int, int);
1107 extern int kill_proc(pid_t, int, int);
1108 extern struct sigqueue *sigqueue_alloc(void);
1109 extern void sigqueue_free(struct sigqueue *);
1110 extern int send_sigqueue(int, struct sigqueue *, struct task_struct *);
1111 extern int send_group_sigqueue(int, struct sigqueue *, struct task_struct *);
1112 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
1113 extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1114
1115 /* These can be the second arg to send_sig_info/send_group_sig_info. */
1116 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
1117 #define SEND_SIG_PRIV ((struct siginfo *) 1)
1118 #define SEND_SIG_FORCED ((struct siginfo *) 2)
1119
1120 static inline int is_si_special(const struct siginfo *info)
1121 {
1122 return info <= SEND_SIG_FORCED;
1123 }
1124
1125 /* True if we are on the alternate signal stack. */
1126
1127 static inline int on_sig_stack(unsigned long sp)
1128 {
1129 return (sp - current->sas_ss_sp < current->sas_ss_size);
1130 }
1131
1132 static inline int sas_ss_flags(unsigned long sp)
1133 {
1134 return (current->sas_ss_size == 0 ? SS_DISABLE
1135 : on_sig_stack(sp) ? SS_ONSTACK : 0);
1136 }
1137
1138 /*
1139 * Routines for handling mm_structs
1140 */
1141 extern struct mm_struct * mm_alloc(void);
1142
1143 /* mmdrop drops the mm and the page tables */
1144 extern void FASTCALL(__mmdrop(struct mm_struct *));
1145 static inline void mmdrop(struct mm_struct * mm)
1146 {
1147 if (atomic_dec_and_test(&mm->mm_count))
1148 __mmdrop(mm);
1149 }
1150
1151 /* mmput gets rid of the mappings and all user-space */
1152 extern void mmput(struct mm_struct *);
1153 /* Grab a reference to a task's mm, if it is not already going away */
1154 extern struct mm_struct *get_task_mm(struct task_struct *task);
1155 /* Remove the current tasks stale references to the old mm_struct */
1156 extern void mm_release(struct task_struct *, struct mm_struct *);
1157
1158 extern int copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1159 extern void flush_thread(void);
1160 extern void exit_thread(void);
1161
1162 extern void exit_files(struct task_struct *);
1163 extern void __cleanup_signal(struct signal_struct *);
1164 extern void __cleanup_sighand(struct sighand_struct *);
1165 extern void exit_itimers(struct signal_struct *);
1166
1167 extern NORET_TYPE void do_group_exit(int);
1168
1169 extern void daemonize(const char *, ...);
1170 extern int allow_signal(int);
1171 extern int disallow_signal(int);
1172 extern task_t *child_reaper;
1173
1174 extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1175 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1176 task_t *fork_idle(int);
1177
1178 extern void set_task_comm(struct task_struct *tsk, char *from);
1179 extern void get_task_comm(char *to, struct task_struct *tsk);
1180
1181 #ifdef CONFIG_SMP
1182 extern void wait_task_inactive(task_t * p);
1183 #else
1184 #define wait_task_inactive(p) do { } while (0)
1185 #endif
1186
1187 #define remove_parent(p) list_del_init(&(p)->sibling)
1188 #define add_parent(p) list_add_tail(&(p)->sibling,&(p)->parent->children)
1189
1190 #define next_task(p) list_entry((p)->tasks.next, struct task_struct, tasks)
1191 #define prev_task(p) list_entry((p)->tasks.prev, struct task_struct, tasks)
1192
1193 #define for_each_process(p) \
1194 for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1195
1196 /*
1197 * Careful: do_each_thread/while_each_thread is a double loop so
1198 * 'break' will not work as expected - use goto instead.
1199 */
1200 #define do_each_thread(g, t) \
1201 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1202
1203 #define while_each_thread(g, t) \
1204 while ((t = next_thread(t)) != g)
1205
1206 #define thread_group_leader(p) (p->pid == p->tgid)
1207
1208 static inline task_t *next_thread(task_t *p)
1209 {
1210 return list_entry(rcu_dereference(p->thread_group.next),
1211 task_t, thread_group);
1212 }
1213
1214 static inline int thread_group_empty(task_t *p)
1215 {
1216 return list_empty(&p->thread_group);
1217 }
1218
1219 #define delay_group_leader(p) \
1220 (thread_group_leader(p) && !thread_group_empty(p))
1221
1222 /*
1223 * Protects ->fs, ->files, ->mm, ->ptrace, ->group_info, ->comm, keyring
1224 * subscriptions and synchronises with wait4(). Also used in procfs. Also
1225 * pins the final release of task.io_context. Also protects ->cpuset.
1226 *
1227 * Nests both inside and outside of read_lock(&tasklist_lock).
1228 * It must not be nested with write_lock_irq(&tasklist_lock),
1229 * neither inside nor outside.
1230 */
1231 static inline void task_lock(struct task_struct *p)
1232 {
1233 spin_lock(&p->alloc_lock);
1234 }
1235
1236 static inline void task_unlock(struct task_struct *p)
1237 {
1238 spin_unlock(&p->alloc_lock);
1239 }
1240
1241 extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
1242 unsigned long *flags);
1243
1244 static inline void unlock_task_sighand(struct task_struct *tsk,
1245 unsigned long *flags)
1246 {
1247 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
1248 }
1249
1250 #ifndef __HAVE_THREAD_FUNCTIONS
1251
1252 #define task_thread_info(task) (task)->thread_info
1253 #define task_stack_page(task) ((void*)((task)->thread_info))
1254
1255 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
1256 {
1257 *task_thread_info(p) = *task_thread_info(org);
1258 task_thread_info(p)->task = p;
1259 }
1260
1261 static inline unsigned long *end_of_stack(struct task_struct *p)
1262 {
1263 return (unsigned long *)(p->thread_info + 1);
1264 }
1265
1266 #endif
1267
1268 /* set thread flags in other task's structures
1269 * - see asm/thread_info.h for TIF_xxxx flags available
1270 */
1271 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1272 {
1273 set_ti_thread_flag(task_thread_info(tsk), flag);
1274 }
1275
1276 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1277 {
1278 clear_ti_thread_flag(task_thread_info(tsk), flag);
1279 }
1280
1281 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1282 {
1283 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1284 }
1285
1286 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1287 {
1288 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1289 }
1290
1291 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1292 {
1293 return test_ti_thread_flag(task_thread_info(tsk), flag);
1294 }
1295
1296 static inline void set_tsk_need_resched(struct task_struct *tsk)
1297 {
1298 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1299 }
1300
1301 static inline void clear_tsk_need_resched(struct task_struct *tsk)
1302 {
1303 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1304 }
1305
1306 static inline int signal_pending(struct task_struct *p)
1307 {
1308 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1309 }
1310
1311 static inline int need_resched(void)
1312 {
1313 return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1314 }
1315
1316 /*
1317 * cond_resched() and cond_resched_lock(): latency reduction via
1318 * explicit rescheduling in places that are safe. The return
1319 * value indicates whether a reschedule was done in fact.
1320 * cond_resched_lock() will drop the spinlock before scheduling,
1321 * cond_resched_softirq() will enable bhs before scheduling.
1322 */
1323 extern int cond_resched(void);
1324 extern int cond_resched_lock(spinlock_t * lock);
1325 extern int cond_resched_softirq(void);
1326
1327 /*
1328 * Does a critical section need to be broken due to another
1329 * task waiting?:
1330 */
1331 #if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
1332 # define need_lockbreak(lock) ((lock)->break_lock)
1333 #else
1334 # define need_lockbreak(lock) 0
1335 #endif
1336
1337 /*
1338 * Does a critical section need to be broken due to another
1339 * task waiting or preemption being signalled:
1340 */
1341 static inline int lock_need_resched(spinlock_t *lock)
1342 {
1343 if (need_lockbreak(lock) || need_resched())
1344 return 1;
1345 return 0;
1346 }
1347
1348 /* Reevaluate whether the task has signals pending delivery.
1349 This is required every time the blocked sigset_t changes.
1350 callers must hold sighand->siglock. */
1351
1352 extern FASTCALL(void recalc_sigpending_tsk(struct task_struct *t));
1353 extern void recalc_sigpending(void);
1354
1355 extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1356
1357 /*
1358 * Wrappers for p->thread_info->cpu access. No-op on UP.
1359 */
1360 #ifdef CONFIG_SMP
1361
1362 static inline unsigned int task_cpu(const struct task_struct *p)
1363 {
1364 return task_thread_info(p)->cpu;
1365 }
1366
1367 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1368 {
1369 task_thread_info(p)->cpu = cpu;
1370 }
1371
1372 #else
1373
1374 static inline unsigned int task_cpu(const struct task_struct *p)
1375 {
1376 return 0;
1377 }
1378
1379 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1380 {
1381 }
1382
1383 #endif /* CONFIG_SMP */
1384
1385 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1386 extern void arch_pick_mmap_layout(struct mm_struct *mm);
1387 #else
1388 static inline void arch_pick_mmap_layout(struct mm_struct *mm)
1389 {
1390 mm->mmap_base = TASK_UNMAPPED_BASE;
1391 mm->get_unmapped_area = arch_get_unmapped_area;
1392 mm->unmap_area = arch_unmap_area;
1393 }
1394 #endif
1395
1396 extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
1397 extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
1398
1399 extern void normalize_rt_tasks(void);
1400
1401 #ifdef CONFIG_PM
1402 /*
1403 * Check if a process has been frozen
1404 */
1405 static inline int frozen(struct task_struct *p)
1406 {
1407 return p->flags & PF_FROZEN;
1408 }
1409
1410 /*
1411 * Check if there is a request to freeze a process
1412 */
1413 static inline int freezing(struct task_struct *p)
1414 {
1415 return p->flags & PF_FREEZE;
1416 }
1417
1418 /*
1419 * Request that a process be frozen
1420 * FIXME: SMP problem. We may not modify other process' flags!
1421 */
1422 static inline void freeze(struct task_struct *p)
1423 {
1424 p->flags |= PF_FREEZE;
1425 }
1426
1427 /*
1428 * Wake up a frozen process
1429 */
1430 static inline int thaw_process(struct task_struct *p)
1431 {
1432 if (frozen(p)) {
1433 p->flags &= ~PF_FROZEN;
1434 wake_up_process(p);
1435 return 1;
1436 }
1437 return 0;
1438 }
1439
1440 /*
1441 * freezing is complete, mark process as frozen
1442 */
1443 static inline void frozen_process(struct task_struct *p)
1444 {
1445 p->flags = (p->flags & ~PF_FREEZE) | PF_FROZEN;
1446 }
1447
1448 extern void refrigerator(void);
1449 extern int freeze_processes(void);
1450 extern void thaw_processes(void);
1451
1452 static inline int try_to_freeze(void)
1453 {
1454 if (freezing(current)) {
1455 refrigerator();
1456 return 1;
1457 } else
1458 return 0;
1459 }
1460 #else
1461 static inline int frozen(struct task_struct *p) { return 0; }
1462 static inline int freezing(struct task_struct *p) { return 0; }
1463 static inline void freeze(struct task_struct *p) { BUG(); }
1464 static inline int thaw_process(struct task_struct *p) { return 1; }
1465 static inline void frozen_process(struct task_struct *p) { BUG(); }
1466
1467 static inline void refrigerator(void) {}
1468 static inline int freeze_processes(void) { BUG(); return 0; }
1469 static inline void thaw_processes(void) {}
1470
1471 static inline int try_to_freeze(void) { return 0; }
1472
1473 #endif /* CONFIG_PM */
1474 #endif /* __KERNEL__ */
1475
1476 #endif
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