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