Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / include / linux / sched.h
1 #ifndef _LINUX_SCHED_H
2 #define _LINUX_SCHED_H
3
4 /*
5 * cloning flags:
6 */
7 #define CSIGNAL 0x000000ff /* signal mask to be sent at exit */
8 #define CLONE_VM 0x00000100 /* set if VM shared between processes */
9 #define CLONE_FS 0x00000200 /* set if fs info shared between processes */
10 #define CLONE_FILES 0x00000400 /* set if open files shared between processes */
11 #define CLONE_SIGHAND 0x00000800 /* set if signal handlers and blocked signals shared */
12 #define CLONE_PTRACE 0x00002000 /* set if we want to let tracing continue on the child too */
13 #define CLONE_VFORK 0x00004000 /* set if the parent wants the child to wake it up on mm_release */
14 #define CLONE_PARENT 0x00008000 /* set if we want to have the same parent as the cloner */
15 #define CLONE_THREAD 0x00010000 /* Same thread group? */
16 #define CLONE_NEWNS 0x00020000 /* New namespace group? */
17 #define CLONE_SYSVSEM 0x00040000 /* share system V SEM_UNDO semantics */
18 #define CLONE_SETTLS 0x00080000 /* create a new TLS for the child */
19 #define CLONE_PARENT_SETTID 0x00100000 /* set the TID in the parent */
20 #define CLONE_CHILD_CLEARTID 0x00200000 /* clear the TID in the child */
21 #define CLONE_DETACHED 0x00400000 /* Unused, ignored */
22 #define CLONE_UNTRACED 0x00800000 /* set if the tracing process can't force CLONE_PTRACE on this clone */
23 #define CLONE_CHILD_SETTID 0x01000000 /* set the TID in the child */
24 #define CLONE_STOPPED 0x02000000 /* Start in stopped state */
25 #define CLONE_NEWUTS 0x04000000 /* New utsname group? */
26 #define CLONE_NEWIPC 0x08000000 /* New ipcs */
27 #define CLONE_NEWUSER 0x10000000 /* New user namespace */
28 #define CLONE_NEWPID 0x20000000 /* New pid namespace */
29 #define CLONE_NEWNET 0x40000000 /* New network namespace */
30 #define CLONE_IO 0x80000000 /* Clone io context */
31
32 /*
33 * Scheduling policies
34 */
35 #define SCHED_NORMAL 0
36 #define SCHED_FIFO 1
37 #define SCHED_RR 2
38 #define SCHED_BATCH 3
39 /* SCHED_ISO: reserved but not implemented yet */
40 #define SCHED_IDLE 5
41
42 #ifdef __KERNEL__
43
44 struct sched_param {
45 int sched_priority;
46 };
47
48 #include <asm/param.h> /* for HZ */
49
50 #include <linux/capability.h>
51 #include <linux/threads.h>
52 #include <linux/kernel.h>
53 #include <linux/types.h>
54 #include <linux/timex.h>
55 #include <linux/jiffies.h>
56 #include <linux/rbtree.h>
57 #include <linux/thread_info.h>
58 #include <linux/cpumask.h>
59 #include <linux/errno.h>
60 #include <linux/nodemask.h>
61 #include <linux/mm_types.h>
62
63 #include <asm/system.h>
64 #include <asm/semaphore.h>
65 #include <asm/page.h>
66 #include <asm/ptrace.h>
67 #include <asm/cputime.h>
68
69 #include <linux/smp.h>
70 #include <linux/sem.h>
71 #include <linux/signal.h>
72 #include <linux/securebits.h>
73 #include <linux/fs_struct.h>
74 #include <linux/compiler.h>
75 #include <linux/completion.h>
76 #include <linux/pid.h>
77 #include <linux/percpu.h>
78 #include <linux/topology.h>
79 #include <linux/proportions.h>
80 #include <linux/seccomp.h>
81 #include <linux/rcupdate.h>
82 #include <linux/rtmutex.h>
83
84 #include <linux/time.h>
85 #include <linux/param.h>
86 #include <linux/resource.h>
87 #include <linux/timer.h>
88 #include <linux/hrtimer.h>
89 #include <linux/task_io_accounting.h>
90 #include <linux/kobject.h>
91 #include <linux/latencytop.h>
92
93 #include <asm/processor.h>
94
95 struct mem_cgroup;
96 struct exec_domain;
97 struct futex_pi_state;
98 struct robust_list_head;
99 struct bio;
100
101 /*
102 * List of flags we want to share for kernel threads,
103 * if only because they are not used by them anyway.
104 */
105 #define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
106
107 /*
108 * These are the constant used to fake the fixed-point load-average
109 * counting. Some notes:
110 * - 11 bit fractions expand to 22 bits by the multiplies: this gives
111 * a load-average precision of 10 bits integer + 11 bits fractional
112 * - if you want to count load-averages more often, you need more
113 * precision, or rounding will get you. With 2-second counting freq,
114 * the EXP_n values would be 1981, 2034 and 2043 if still using only
115 * 11 bit fractions.
116 */
117 extern unsigned long avenrun[]; /* Load averages */
118
119 #define FSHIFT 11 /* nr of bits of precision */
120 #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
121 #define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */
122 #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
123 #define EXP_5 2014 /* 1/exp(5sec/5min) */
124 #define EXP_15 2037 /* 1/exp(5sec/15min) */
125
126 #define CALC_LOAD(load,exp,n) \
127 load *= exp; \
128 load += n*(FIXED_1-exp); \
129 load >>= FSHIFT;
130
131 extern unsigned long total_forks;
132 extern int nr_threads;
133 DECLARE_PER_CPU(unsigned long, process_counts);
134 extern int nr_processes(void);
135 extern unsigned long nr_running(void);
136 extern unsigned long nr_uninterruptible(void);
137 extern unsigned long nr_active(void);
138 extern unsigned long nr_iowait(void);
139 extern unsigned long weighted_cpuload(const int cpu);
140
141 struct seq_file;
142 struct cfs_rq;
143 struct task_group;
144 #ifdef CONFIG_SCHED_DEBUG
145 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
146 extern void proc_sched_set_task(struct task_struct *p);
147 extern void
148 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
149 #else
150 static inline void
151 proc_sched_show_task(struct task_struct *p, struct seq_file *m)
152 {
153 }
154 static inline void proc_sched_set_task(struct task_struct *p)
155 {
156 }
157 static inline void
158 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
159 {
160 }
161 #endif
162
163 /*
164 * Task state bitmask. NOTE! These bits are also
165 * encoded in fs/proc/array.c: get_task_state().
166 *
167 * We have two separate sets of flags: task->state
168 * is about runnability, while task->exit_state are
169 * about the task exiting. Confusing, but this way
170 * modifying one set can't modify the other one by
171 * mistake.
172 */
173 #define TASK_RUNNING 0
174 #define TASK_INTERRUPTIBLE 1
175 #define TASK_UNINTERRUPTIBLE 2
176 #define __TASK_STOPPED 4
177 #define __TASK_TRACED 8
178 /* in tsk->exit_state */
179 #define EXIT_ZOMBIE 16
180 #define EXIT_DEAD 32
181 /* in tsk->state again */
182 #define TASK_DEAD 64
183 #define TASK_WAKEKILL 128
184
185 /* Convenience macros for the sake of set_task_state */
186 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
187 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)
188 #define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED)
189
190 /* Convenience macros for the sake of wake_up */
191 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
192 #define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
193
194 /* get_task_state() */
195 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \
196 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
197 __TASK_TRACED)
198
199 #define task_is_traced(task) ((task->state & __TASK_TRACED) != 0)
200 #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0)
201 #define task_is_stopped_or_traced(task) \
202 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
203 #define task_contributes_to_load(task) \
204 ((task->state & TASK_UNINTERRUPTIBLE) != 0)
205
206 #define __set_task_state(tsk, state_value) \
207 do { (tsk)->state = (state_value); } while (0)
208 #define set_task_state(tsk, state_value) \
209 set_mb((tsk)->state, (state_value))
210
211 /*
212 * set_current_state() includes a barrier so that the write of current->state
213 * is correctly serialised wrt the caller's subsequent test of whether to
214 * actually sleep:
215 *
216 * set_current_state(TASK_UNINTERRUPTIBLE);
217 * if (do_i_need_to_sleep())
218 * schedule();
219 *
220 * If the caller does not need such serialisation then use __set_current_state()
221 */
222 #define __set_current_state(state_value) \
223 do { current->state = (state_value); } while (0)
224 #define set_current_state(state_value) \
225 set_mb(current->state, (state_value))
226
227 /* Task command name length */
228 #define TASK_COMM_LEN 16
229
230 #include <linux/spinlock.h>
231
232 /*
233 * This serializes "schedule()" and also protects
234 * the run-queue from deletions/modifications (but
235 * _adding_ to the beginning of the run-queue has
236 * a separate lock).
237 */
238 extern rwlock_t tasklist_lock;
239 extern spinlock_t mmlist_lock;
240
241 struct task_struct;
242
243 extern void sched_init(void);
244 extern void sched_init_smp(void);
245 extern asmlinkage void schedule_tail(struct task_struct *prev);
246 extern void init_idle(struct task_struct *idle, int cpu);
247 extern void init_idle_bootup_task(struct task_struct *idle);
248
249 extern cpumask_t nohz_cpu_mask;
250 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
251 extern int select_nohz_load_balancer(int cpu);
252 #else
253 static inline int select_nohz_load_balancer(int cpu)
254 {
255 return 0;
256 }
257 #endif
258
259 extern unsigned long rt_needs_cpu(int cpu);
260
261 /*
262 * Only dump TASK_* tasks. (0 for all tasks)
263 */
264 extern void show_state_filter(unsigned long state_filter);
265
266 static inline void show_state(void)
267 {
268 show_state_filter(0);
269 }
270
271 extern void show_regs(struct pt_regs *);
272
273 /*
274 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
275 * task), SP is the stack pointer of the first frame that should be shown in the back
276 * trace (or NULL if the entire call-chain of the task should be shown).
277 */
278 extern void show_stack(struct task_struct *task, unsigned long *sp);
279
280 void io_schedule(void);
281 long io_schedule_timeout(long timeout);
282
283 extern void cpu_init (void);
284 extern void trap_init(void);
285 extern void account_process_tick(struct task_struct *task, int user);
286 extern void update_process_times(int user);
287 extern void scheduler_tick(void);
288 extern void hrtick_resched(void);
289
290 extern void sched_show_task(struct task_struct *p);
291
292 #ifdef CONFIG_DETECT_SOFTLOCKUP
293 extern void softlockup_tick(void);
294 extern void spawn_softlockup_task(void);
295 extern void touch_softlockup_watchdog(void);
296 extern void touch_all_softlockup_watchdogs(void);
297 extern unsigned long softlockup_thresh;
298 extern unsigned long sysctl_hung_task_check_count;
299 extern unsigned long sysctl_hung_task_timeout_secs;
300 extern unsigned long sysctl_hung_task_warnings;
301 #else
302 static inline void softlockup_tick(void)
303 {
304 }
305 static inline void spawn_softlockup_task(void)
306 {
307 }
308 static inline void touch_softlockup_watchdog(void)
309 {
310 }
311 static inline void touch_all_softlockup_watchdogs(void)
312 {
313 }
314 #endif
315
316
317 /* Attach to any functions which should be ignored in wchan output. */
318 #define __sched __attribute__((__section__(".sched.text")))
319
320 /* Linker adds these: start and end of __sched functions */
321 extern char __sched_text_start[], __sched_text_end[];
322
323 /* Is this address in the __sched functions? */
324 extern int in_sched_functions(unsigned long addr);
325
326 #define MAX_SCHEDULE_TIMEOUT LONG_MAX
327 extern signed long schedule_timeout(signed long timeout);
328 extern signed long schedule_timeout_interruptible(signed long timeout);
329 extern signed long schedule_timeout_killable(signed long timeout);
330 extern signed long schedule_timeout_uninterruptible(signed long timeout);
331 asmlinkage void schedule(void);
332
333 struct nsproxy;
334 struct user_namespace;
335
336 /* Maximum number of active map areas.. This is a random (large) number */
337 #define DEFAULT_MAX_MAP_COUNT 65536
338
339 extern int sysctl_max_map_count;
340
341 #include <linux/aio.h>
342
343 extern unsigned long
344 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
345 unsigned long, unsigned long);
346 extern unsigned long
347 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
348 unsigned long len, unsigned long pgoff,
349 unsigned long flags);
350 extern void arch_unmap_area(struct mm_struct *, unsigned long);
351 extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
352
353 #if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
354 /*
355 * The mm counters are not protected by its page_table_lock,
356 * so must be incremented atomically.
357 */
358 #define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
359 #define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
360 #define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
361 #define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
362 #define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
363
364 #else /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
365 /*
366 * The mm counters are protected by its page_table_lock,
367 * so can be incremented directly.
368 */
369 #define set_mm_counter(mm, member, value) (mm)->_##member = (value)
370 #define get_mm_counter(mm, member) ((mm)->_##member)
371 #define add_mm_counter(mm, member, value) (mm)->_##member += (value)
372 #define inc_mm_counter(mm, member) (mm)->_##member++
373 #define dec_mm_counter(mm, member) (mm)->_##member--
374
375 #endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
376
377 #define get_mm_rss(mm) \
378 (get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
379 #define update_hiwater_rss(mm) do { \
380 unsigned long _rss = get_mm_rss(mm); \
381 if ((mm)->hiwater_rss < _rss) \
382 (mm)->hiwater_rss = _rss; \
383 } while (0)
384 #define update_hiwater_vm(mm) do { \
385 if ((mm)->hiwater_vm < (mm)->total_vm) \
386 (mm)->hiwater_vm = (mm)->total_vm; \
387 } while (0)
388
389 extern void set_dumpable(struct mm_struct *mm, int value);
390 extern int get_dumpable(struct mm_struct *mm);
391
392 /* mm flags */
393 /* dumpable bits */
394 #define MMF_DUMPABLE 0 /* core dump is permitted */
395 #define MMF_DUMP_SECURELY 1 /* core file is readable only by root */
396 #define MMF_DUMPABLE_BITS 2
397
398 /* coredump filter bits */
399 #define MMF_DUMP_ANON_PRIVATE 2
400 #define MMF_DUMP_ANON_SHARED 3
401 #define MMF_DUMP_MAPPED_PRIVATE 4
402 #define MMF_DUMP_MAPPED_SHARED 5
403 #define MMF_DUMP_ELF_HEADERS 6
404 #define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS
405 #define MMF_DUMP_FILTER_BITS 5
406 #define MMF_DUMP_FILTER_MASK \
407 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
408 #define MMF_DUMP_FILTER_DEFAULT \
409 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED))
410
411 struct sighand_struct {
412 atomic_t count;
413 struct k_sigaction action[_NSIG];
414 spinlock_t siglock;
415 wait_queue_head_t signalfd_wqh;
416 };
417
418 struct pacct_struct {
419 int ac_flag;
420 long ac_exitcode;
421 unsigned long ac_mem;
422 cputime_t ac_utime, ac_stime;
423 unsigned long ac_minflt, ac_majflt;
424 };
425
426 /*
427 * NOTE! "signal_struct" does not have it's own
428 * locking, because a shared signal_struct always
429 * implies a shared sighand_struct, so locking
430 * sighand_struct is always a proper superset of
431 * the locking of signal_struct.
432 */
433 struct signal_struct {
434 atomic_t count;
435 atomic_t live;
436
437 wait_queue_head_t wait_chldexit; /* for wait4() */
438
439 /* current thread group signal load-balancing target: */
440 struct task_struct *curr_target;
441
442 /* shared signal handling: */
443 struct sigpending shared_pending;
444
445 /* thread group exit support */
446 int group_exit_code;
447 /* overloaded:
448 * - notify group_exit_task when ->count is equal to notify_count
449 * - everyone except group_exit_task is stopped during signal delivery
450 * of fatal signals, group_exit_task processes the signal.
451 */
452 struct task_struct *group_exit_task;
453 int notify_count;
454
455 /* thread group stop support, overloads group_exit_code too */
456 int group_stop_count;
457 unsigned int flags; /* see SIGNAL_* flags below */
458
459 /* POSIX.1b Interval Timers */
460 struct list_head posix_timers;
461
462 /* ITIMER_REAL timer for the process */
463 struct hrtimer real_timer;
464 struct pid *leader_pid;
465 ktime_t it_real_incr;
466
467 /* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
468 cputime_t it_prof_expires, it_virt_expires;
469 cputime_t it_prof_incr, it_virt_incr;
470
471 /* job control IDs */
472
473 /*
474 * pgrp and session fields are deprecated.
475 * use the task_session_Xnr and task_pgrp_Xnr routines below
476 */
477
478 union {
479 pid_t pgrp __deprecated;
480 pid_t __pgrp;
481 };
482
483 struct pid *tty_old_pgrp;
484
485 union {
486 pid_t session __deprecated;
487 pid_t __session;
488 };
489
490 /* boolean value for session group leader */
491 int leader;
492
493 struct tty_struct *tty; /* NULL if no tty */
494
495 /*
496 * Cumulative resource counters for dead threads in the group,
497 * and for reaped dead child processes forked by this group.
498 * Live threads maintain their own counters and add to these
499 * in __exit_signal, except for the group leader.
500 */
501 cputime_t utime, stime, cutime, cstime;
502 cputime_t gtime;
503 cputime_t cgtime;
504 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
505 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
506 unsigned long inblock, oublock, cinblock, coublock;
507
508 /*
509 * Cumulative ns of scheduled CPU time for dead threads in the
510 * group, not including a zombie group leader. (This only differs
511 * from jiffies_to_ns(utime + stime) if sched_clock uses something
512 * other than jiffies.)
513 */
514 unsigned long long sum_sched_runtime;
515
516 /*
517 * We don't bother to synchronize most readers of this at all,
518 * because there is no reader checking a limit that actually needs
519 * to get both rlim_cur and rlim_max atomically, and either one
520 * alone is a single word that can safely be read normally.
521 * getrlimit/setrlimit use task_lock(current->group_leader) to
522 * protect this instead of the siglock, because they really
523 * have no need to disable irqs.
524 */
525 struct rlimit rlim[RLIM_NLIMITS];
526
527 struct list_head cpu_timers[3];
528
529 /* keep the process-shared keyrings here so that they do the right
530 * thing in threads created with CLONE_THREAD */
531 #ifdef CONFIG_KEYS
532 struct key *session_keyring; /* keyring inherited over fork */
533 struct key *process_keyring; /* keyring private to this process */
534 #endif
535 #ifdef CONFIG_BSD_PROCESS_ACCT
536 struct pacct_struct pacct; /* per-process accounting information */
537 #endif
538 #ifdef CONFIG_TASKSTATS
539 struct taskstats *stats;
540 #endif
541 #ifdef CONFIG_AUDIT
542 unsigned audit_tty;
543 struct tty_audit_buf *tty_audit_buf;
544 #endif
545 };
546
547 /* Context switch must be unlocked if interrupts are to be enabled */
548 #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
549 # define __ARCH_WANT_UNLOCKED_CTXSW
550 #endif
551
552 /*
553 * Bits in flags field of signal_struct.
554 */
555 #define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */
556 #define SIGNAL_STOP_DEQUEUED 0x00000002 /* stop signal dequeued */
557 #define SIGNAL_STOP_CONTINUED 0x00000004 /* SIGCONT since WCONTINUED reap */
558 #define SIGNAL_GROUP_EXIT 0x00000008 /* group exit in progress */
559
560 /* If true, all threads except ->group_exit_task have pending SIGKILL */
561 static inline int signal_group_exit(const struct signal_struct *sig)
562 {
563 return (sig->flags & SIGNAL_GROUP_EXIT) ||
564 (sig->group_exit_task != NULL);
565 }
566
567 /*
568 * Some day this will be a full-fledged user tracking system..
569 */
570 struct user_struct {
571 atomic_t __count; /* reference count */
572 atomic_t processes; /* How many processes does this user have? */
573 atomic_t files; /* How many open files does this user have? */
574 atomic_t sigpending; /* How many pending signals does this user have? */
575 #ifdef CONFIG_INOTIFY_USER
576 atomic_t inotify_watches; /* How many inotify watches does this user have? */
577 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */
578 #endif
579 #ifdef CONFIG_POSIX_MQUEUE
580 /* protected by mq_lock */
581 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
582 #endif
583 unsigned long locked_shm; /* How many pages of mlocked shm ? */
584
585 #ifdef CONFIG_KEYS
586 struct key *uid_keyring; /* UID specific keyring */
587 struct key *session_keyring; /* UID's default session keyring */
588 #endif
589
590 /* Hash table maintenance information */
591 struct hlist_node uidhash_node;
592 uid_t uid;
593
594 #ifdef CONFIG_USER_SCHED
595 struct task_group *tg;
596 #ifdef CONFIG_SYSFS
597 struct kobject kobj;
598 struct work_struct work;
599 #endif
600 #endif
601 };
602
603 extern int uids_sysfs_init(void);
604
605 extern struct user_struct *find_user(uid_t);
606
607 extern struct user_struct root_user;
608 #define INIT_USER (&root_user)
609
610 struct backing_dev_info;
611 struct reclaim_state;
612
613 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
614 struct sched_info {
615 /* cumulative counters */
616 unsigned long pcount; /* # of times run on this cpu */
617 unsigned long long cpu_time, /* time spent on the cpu */
618 run_delay; /* time spent waiting on a runqueue */
619
620 /* timestamps */
621 unsigned long long last_arrival,/* when we last ran on a cpu */
622 last_queued; /* when we were last queued to run */
623 #ifdef CONFIG_SCHEDSTATS
624 /* BKL stats */
625 unsigned int bkl_count;
626 #endif
627 };
628 #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
629
630 #ifdef CONFIG_SCHEDSTATS
631 extern const struct file_operations proc_schedstat_operations;
632 #endif /* CONFIG_SCHEDSTATS */
633
634 #ifdef CONFIG_TASK_DELAY_ACCT
635 struct task_delay_info {
636 spinlock_t lock;
637 unsigned int flags; /* Private per-task flags */
638
639 /* For each stat XXX, add following, aligned appropriately
640 *
641 * struct timespec XXX_start, XXX_end;
642 * u64 XXX_delay;
643 * u32 XXX_count;
644 *
645 * Atomicity of updates to XXX_delay, XXX_count protected by
646 * single lock above (split into XXX_lock if contention is an issue).
647 */
648
649 /*
650 * XXX_count is incremented on every XXX operation, the delay
651 * associated with the operation is added to XXX_delay.
652 * XXX_delay contains the accumulated delay time in nanoseconds.
653 */
654 struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */
655 u64 blkio_delay; /* wait for sync block io completion */
656 u64 swapin_delay; /* wait for swapin block io completion */
657 u32 blkio_count; /* total count of the number of sync block */
658 /* io operations performed */
659 u32 swapin_count; /* total count of the number of swapin block */
660 /* io operations performed */
661 };
662 #endif /* CONFIG_TASK_DELAY_ACCT */
663
664 static inline int sched_info_on(void)
665 {
666 #ifdef CONFIG_SCHEDSTATS
667 return 1;
668 #elif defined(CONFIG_TASK_DELAY_ACCT)
669 extern int delayacct_on;
670 return delayacct_on;
671 #else
672 return 0;
673 #endif
674 }
675
676 enum cpu_idle_type {
677 CPU_IDLE,
678 CPU_NOT_IDLE,
679 CPU_NEWLY_IDLE,
680 CPU_MAX_IDLE_TYPES
681 };
682
683 /*
684 * sched-domains (multiprocessor balancing) declarations:
685 */
686
687 /*
688 * Increase resolution of nice-level calculations:
689 */
690 #define SCHED_LOAD_SHIFT 10
691 #define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT)
692
693 #define SCHED_LOAD_SCALE_FUZZ SCHED_LOAD_SCALE
694
695 #ifdef CONFIG_SMP
696 #define SD_LOAD_BALANCE 1 /* Do load balancing on this domain. */
697 #define SD_BALANCE_NEWIDLE 2 /* Balance when about to become idle */
698 #define SD_BALANCE_EXEC 4 /* Balance on exec */
699 #define SD_BALANCE_FORK 8 /* Balance on fork, clone */
700 #define SD_WAKE_IDLE 16 /* Wake to idle CPU on task wakeup */
701 #define SD_WAKE_AFFINE 32 /* Wake task to waking CPU */
702 #define SD_WAKE_BALANCE 64 /* Perform balancing at task wakeup */
703 #define SD_SHARE_CPUPOWER 128 /* Domain members share cpu power */
704 #define SD_POWERSAVINGS_BALANCE 256 /* Balance for power savings */
705 #define SD_SHARE_PKG_RESOURCES 512 /* Domain members share cpu pkg resources */
706 #define SD_SERIALIZE 1024 /* Only a single load balancing instance */
707
708 #define BALANCE_FOR_MC_POWER \
709 (sched_smt_power_savings ? SD_POWERSAVINGS_BALANCE : 0)
710
711 #define BALANCE_FOR_PKG_POWER \
712 ((sched_mc_power_savings || sched_smt_power_savings) ? \
713 SD_POWERSAVINGS_BALANCE : 0)
714
715 #define test_sd_parent(sd, flag) ((sd->parent && \
716 (sd->parent->flags & flag)) ? 1 : 0)
717
718
719 struct sched_group {
720 struct sched_group *next; /* Must be a circular list */
721 cpumask_t cpumask;
722
723 /*
724 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
725 * single CPU. This is read only (except for setup, hotplug CPU).
726 * Note : Never change cpu_power without recompute its reciprocal
727 */
728 unsigned int __cpu_power;
729 /*
730 * reciprocal value of cpu_power to avoid expensive divides
731 * (see include/linux/reciprocal_div.h)
732 */
733 u32 reciprocal_cpu_power;
734 };
735
736 struct sched_domain {
737 /* These fields must be setup */
738 struct sched_domain *parent; /* top domain must be null terminated */
739 struct sched_domain *child; /* bottom domain must be null terminated */
740 struct sched_group *groups; /* the balancing groups of the domain */
741 cpumask_t span; /* span of all CPUs in this domain */
742 unsigned long min_interval; /* Minimum balance interval ms */
743 unsigned long max_interval; /* Maximum balance interval ms */
744 unsigned int busy_factor; /* less balancing by factor if busy */
745 unsigned int imbalance_pct; /* No balance until over watermark */
746 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */
747 unsigned int busy_idx;
748 unsigned int idle_idx;
749 unsigned int newidle_idx;
750 unsigned int wake_idx;
751 unsigned int forkexec_idx;
752 int flags; /* See SD_* */
753
754 /* Runtime fields. */
755 unsigned long last_balance; /* init to jiffies. units in jiffies */
756 unsigned int balance_interval; /* initialise to 1. units in ms. */
757 unsigned int nr_balance_failed; /* initialise to 0 */
758
759 #ifdef CONFIG_SCHEDSTATS
760 /* load_balance() stats */
761 unsigned int lb_count[CPU_MAX_IDLE_TYPES];
762 unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
763 unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
764 unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
765 unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
766 unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
767 unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
768 unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
769
770 /* Active load balancing */
771 unsigned int alb_count;
772 unsigned int alb_failed;
773 unsigned int alb_pushed;
774
775 /* SD_BALANCE_EXEC stats */
776 unsigned int sbe_count;
777 unsigned int sbe_balanced;
778 unsigned int sbe_pushed;
779
780 /* SD_BALANCE_FORK stats */
781 unsigned int sbf_count;
782 unsigned int sbf_balanced;
783 unsigned int sbf_pushed;
784
785 /* try_to_wake_up() stats */
786 unsigned int ttwu_wake_remote;
787 unsigned int ttwu_move_affine;
788 unsigned int ttwu_move_balance;
789 #endif
790 };
791
792 extern void partition_sched_domains(int ndoms_new, cpumask_t *doms_new);
793 extern int arch_reinit_sched_domains(void);
794
795 #endif /* CONFIG_SMP */
796
797 /*
798 * A runqueue laden with a single nice 0 task scores a weighted_cpuload of
799 * SCHED_LOAD_SCALE. This function returns 1 if any cpu is laden with a
800 * task of nice 0 or enough lower priority tasks to bring up the
801 * weighted_cpuload
802 */
803 static inline int above_background_load(void)
804 {
805 unsigned long cpu;
806
807 for_each_online_cpu(cpu) {
808 if (weighted_cpuload(cpu) >= SCHED_LOAD_SCALE)
809 return 1;
810 }
811 return 0;
812 }
813
814 struct io_context; /* See blkdev.h */
815 #define NGROUPS_SMALL 32
816 #define NGROUPS_PER_BLOCK ((unsigned int)(PAGE_SIZE / sizeof(gid_t)))
817 struct group_info {
818 int ngroups;
819 atomic_t usage;
820 gid_t small_block[NGROUPS_SMALL];
821 int nblocks;
822 gid_t *blocks[0];
823 };
824
825 /*
826 * get_group_info() must be called with the owning task locked (via task_lock())
827 * when task != current. The reason being that the vast majority of callers are
828 * looking at current->group_info, which can not be changed except by the
829 * current task. Changing current->group_info requires the task lock, too.
830 */
831 #define get_group_info(group_info) do { \
832 atomic_inc(&(group_info)->usage); \
833 } while (0)
834
835 #define put_group_info(group_info) do { \
836 if (atomic_dec_and_test(&(group_info)->usage)) \
837 groups_free(group_info); \
838 } while (0)
839
840 extern struct group_info *groups_alloc(int gidsetsize);
841 extern void groups_free(struct group_info *group_info);
842 extern int set_current_groups(struct group_info *group_info);
843 extern int groups_search(struct group_info *group_info, gid_t grp);
844 /* access the groups "array" with this macro */
845 #define GROUP_AT(gi, i) \
846 ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
847
848 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
849 extern void prefetch_stack(struct task_struct *t);
850 #else
851 static inline void prefetch_stack(struct task_struct *t) { }
852 #endif
853
854 struct audit_context; /* See audit.c */
855 struct mempolicy;
856 struct pipe_inode_info;
857 struct uts_namespace;
858
859 struct rq;
860 struct sched_domain;
861
862 struct sched_class {
863 const struct sched_class *next;
864
865 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int wakeup);
866 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int sleep);
867 void (*yield_task) (struct rq *rq);
868 int (*select_task_rq)(struct task_struct *p, int sync);
869
870 void (*check_preempt_curr) (struct rq *rq, struct task_struct *p);
871
872 struct task_struct * (*pick_next_task) (struct rq *rq);
873 void (*put_prev_task) (struct rq *rq, struct task_struct *p);
874
875 #ifdef CONFIG_SMP
876 unsigned long (*load_balance) (struct rq *this_rq, int this_cpu,
877 struct rq *busiest, unsigned long max_load_move,
878 struct sched_domain *sd, enum cpu_idle_type idle,
879 int *all_pinned, int *this_best_prio);
880
881 int (*move_one_task) (struct rq *this_rq, int this_cpu,
882 struct rq *busiest, struct sched_domain *sd,
883 enum cpu_idle_type idle);
884 void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
885 void (*post_schedule) (struct rq *this_rq);
886 void (*task_wake_up) (struct rq *this_rq, struct task_struct *task);
887 #endif
888
889 void (*set_curr_task) (struct rq *rq);
890 void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
891 void (*task_new) (struct rq *rq, struct task_struct *p);
892 void (*set_cpus_allowed)(struct task_struct *p, cpumask_t *newmask);
893
894 void (*join_domain)(struct rq *rq);
895 void (*leave_domain)(struct rq *rq);
896
897 void (*switched_from) (struct rq *this_rq, struct task_struct *task,
898 int running);
899 void (*switched_to) (struct rq *this_rq, struct task_struct *task,
900 int running);
901 void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
902 int oldprio, int running);
903
904 #ifdef CONFIG_FAIR_GROUP_SCHED
905 void (*moved_group) (struct task_struct *p);
906 #endif
907 };
908
909 struct load_weight {
910 unsigned long weight, inv_weight;
911 };
912
913 /*
914 * CFS stats for a schedulable entity (task, task-group etc)
915 *
916 * Current field usage histogram:
917 *
918 * 4 se->block_start
919 * 4 se->run_node
920 * 4 se->sleep_start
921 * 6 se->load.weight
922 */
923 struct sched_entity {
924 struct load_weight load; /* for load-balancing */
925 struct rb_node run_node;
926 unsigned int on_rq;
927
928 u64 exec_start;
929 u64 sum_exec_runtime;
930 u64 vruntime;
931 u64 prev_sum_exec_runtime;
932
933 u64 last_wakeup;
934 u64 avg_overlap;
935
936 #ifdef CONFIG_SCHEDSTATS
937 u64 wait_start;
938 u64 wait_max;
939 u64 wait_count;
940 u64 wait_sum;
941
942 u64 sleep_start;
943 u64 sleep_max;
944 s64 sum_sleep_runtime;
945
946 u64 block_start;
947 u64 block_max;
948 u64 exec_max;
949 u64 slice_max;
950
951 u64 nr_migrations;
952 u64 nr_migrations_cold;
953 u64 nr_failed_migrations_affine;
954 u64 nr_failed_migrations_running;
955 u64 nr_failed_migrations_hot;
956 u64 nr_forced_migrations;
957 u64 nr_forced2_migrations;
958
959 u64 nr_wakeups;
960 u64 nr_wakeups_sync;
961 u64 nr_wakeups_migrate;
962 u64 nr_wakeups_local;
963 u64 nr_wakeups_remote;
964 u64 nr_wakeups_affine;
965 u64 nr_wakeups_affine_attempts;
966 u64 nr_wakeups_passive;
967 u64 nr_wakeups_idle;
968 #endif
969
970 #ifdef CONFIG_FAIR_GROUP_SCHED
971 struct sched_entity *parent;
972 /* rq on which this entity is (to be) queued: */
973 struct cfs_rq *cfs_rq;
974 /* rq "owned" by this entity/group: */
975 struct cfs_rq *my_q;
976 #endif
977 };
978
979 struct sched_rt_entity {
980 struct list_head run_list;
981 unsigned int time_slice;
982 unsigned long timeout;
983 int nr_cpus_allowed;
984
985 #ifdef CONFIG_RT_GROUP_SCHED
986 struct sched_rt_entity *parent;
987 /* rq on which this entity is (to be) queued: */
988 struct rt_rq *rt_rq;
989 /* rq "owned" by this entity/group: */
990 struct rt_rq *my_q;
991 #endif
992 };
993
994 struct task_struct {
995 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
996 void *stack;
997 atomic_t usage;
998 unsigned int flags; /* per process flags, defined below */
999 unsigned int ptrace;
1000
1001 int lock_depth; /* BKL lock depth */
1002
1003 #ifdef CONFIG_SMP
1004 #ifdef __ARCH_WANT_UNLOCKED_CTXSW
1005 int oncpu;
1006 #endif
1007 #endif
1008
1009 int prio, static_prio, normal_prio;
1010 const struct sched_class *sched_class;
1011 struct sched_entity se;
1012 struct sched_rt_entity rt;
1013
1014 #ifdef CONFIG_PREEMPT_NOTIFIERS
1015 /* list of struct preempt_notifier: */
1016 struct hlist_head preempt_notifiers;
1017 #endif
1018
1019 /*
1020 * fpu_counter contains the number of consecutive context switches
1021 * that the FPU is used. If this is over a threshold, the lazy fpu
1022 * saving becomes unlazy to save the trap. This is an unsigned char
1023 * so that after 256 times the counter wraps and the behavior turns
1024 * lazy again; this to deal with bursty apps that only use FPU for
1025 * a short time
1026 */
1027 unsigned char fpu_counter;
1028 s8 oomkilladj; /* OOM kill score adjustment (bit shift). */
1029 #ifdef CONFIG_BLK_DEV_IO_TRACE
1030 unsigned int btrace_seq;
1031 #endif
1032
1033 unsigned int policy;
1034 cpumask_t cpus_allowed;
1035
1036 #ifdef CONFIG_PREEMPT_RCU
1037 int rcu_read_lock_nesting;
1038 int rcu_flipctr_idx;
1039 #endif /* #ifdef CONFIG_PREEMPT_RCU */
1040
1041 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1042 struct sched_info sched_info;
1043 #endif
1044
1045 struct list_head tasks;
1046 /*
1047 * ptrace_list/ptrace_children forms the list of my children
1048 * that were stolen by a ptracer.
1049 */
1050 struct list_head ptrace_children;
1051 struct list_head ptrace_list;
1052
1053 struct mm_struct *mm, *active_mm;
1054
1055 /* task state */
1056 struct linux_binfmt *binfmt;
1057 int exit_state;
1058 int exit_code, exit_signal;
1059 int pdeath_signal; /* The signal sent when the parent dies */
1060 /* ??? */
1061 unsigned int personality;
1062 unsigned did_exec:1;
1063 pid_t pid;
1064 pid_t tgid;
1065
1066 #ifdef CONFIG_CC_STACKPROTECTOR
1067 /* Canary value for the -fstack-protector gcc feature */
1068 unsigned long stack_canary;
1069 #endif
1070 /*
1071 * pointers to (original) parent process, youngest child, younger sibling,
1072 * older sibling, respectively. (p->father can be replaced with
1073 * p->parent->pid)
1074 */
1075 struct task_struct *real_parent; /* real parent process (when being debugged) */
1076 struct task_struct *parent; /* parent process */
1077 /*
1078 * children/sibling forms the list of my children plus the
1079 * tasks I'm ptracing.
1080 */
1081 struct list_head children; /* list of my children */
1082 struct list_head sibling; /* linkage in my parent's children list */
1083 struct task_struct *group_leader; /* threadgroup leader */
1084
1085 /* PID/PID hash table linkage. */
1086 struct pid_link pids[PIDTYPE_MAX];
1087 struct list_head thread_group;
1088
1089 struct completion *vfork_done; /* for vfork() */
1090 int __user *set_child_tid; /* CLONE_CHILD_SETTID */
1091 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
1092
1093 unsigned int rt_priority;
1094 cputime_t utime, stime, utimescaled, stimescaled;
1095 cputime_t gtime;
1096 cputime_t prev_utime, prev_stime;
1097 unsigned long nvcsw, nivcsw; /* context switch counts */
1098 struct timespec start_time; /* monotonic time */
1099 struct timespec real_start_time; /* boot based time */
1100 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1101 unsigned long min_flt, maj_flt;
1102
1103 cputime_t it_prof_expires, it_virt_expires;
1104 unsigned long long it_sched_expires;
1105 struct list_head cpu_timers[3];
1106
1107 /* process credentials */
1108 uid_t uid,euid,suid,fsuid;
1109 gid_t gid,egid,sgid,fsgid;
1110 struct group_info *group_info;
1111 kernel_cap_t cap_effective, cap_inheritable, cap_permitted, cap_bset;
1112 unsigned keep_capabilities:1;
1113 struct user_struct *user;
1114 #ifdef CONFIG_KEYS
1115 struct key *request_key_auth; /* assumed request_key authority */
1116 struct key *thread_keyring; /* keyring private to this thread */
1117 unsigned char jit_keyring; /* default keyring to attach requested keys to */
1118 #endif
1119 char comm[TASK_COMM_LEN]; /* executable name excluding path
1120 - access with [gs]et_task_comm (which lock
1121 it with task_lock())
1122 - initialized normally by flush_old_exec */
1123 /* file system info */
1124 int link_count, total_link_count;
1125 #ifdef CONFIG_SYSVIPC
1126 /* ipc stuff */
1127 struct sysv_sem sysvsem;
1128 #endif
1129 #ifdef CONFIG_DETECT_SOFTLOCKUP
1130 /* hung task detection */
1131 unsigned long last_switch_timestamp;
1132 unsigned long last_switch_count;
1133 #endif
1134 /* CPU-specific state of this task */
1135 struct thread_struct thread;
1136 /* filesystem information */
1137 struct fs_struct *fs;
1138 /* open file information */
1139 struct files_struct *files;
1140 /* namespaces */
1141 struct nsproxy *nsproxy;
1142 /* signal handlers */
1143 struct signal_struct *signal;
1144 struct sighand_struct *sighand;
1145
1146 sigset_t blocked, real_blocked;
1147 sigset_t saved_sigmask; /* To be restored with TIF_RESTORE_SIGMASK */
1148 struct sigpending pending;
1149
1150 unsigned long sas_ss_sp;
1151 size_t sas_ss_size;
1152 int (*notifier)(void *priv);
1153 void *notifier_data;
1154 sigset_t *notifier_mask;
1155 #ifdef CONFIG_SECURITY
1156 void *security;
1157 #endif
1158 struct audit_context *audit_context;
1159 #ifdef CONFIG_AUDITSYSCALL
1160 uid_t loginuid;
1161 unsigned int sessionid;
1162 #endif
1163 seccomp_t seccomp;
1164
1165 /* Thread group tracking */
1166 u32 parent_exec_id;
1167 u32 self_exec_id;
1168 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
1169 spinlock_t alloc_lock;
1170
1171 /* Protection of the PI data structures: */
1172 spinlock_t pi_lock;
1173
1174 #ifdef CONFIG_RT_MUTEXES
1175 /* PI waiters blocked on a rt_mutex held by this task */
1176 struct plist_head pi_waiters;
1177 /* Deadlock detection and priority inheritance handling */
1178 struct rt_mutex_waiter *pi_blocked_on;
1179 #endif
1180
1181 #ifdef CONFIG_DEBUG_MUTEXES
1182 /* mutex deadlock detection */
1183 struct mutex_waiter *blocked_on;
1184 #endif
1185 #ifdef CONFIG_TRACE_IRQFLAGS
1186 unsigned int irq_events;
1187 int hardirqs_enabled;
1188 unsigned long hardirq_enable_ip;
1189 unsigned int hardirq_enable_event;
1190 unsigned long hardirq_disable_ip;
1191 unsigned int hardirq_disable_event;
1192 int softirqs_enabled;
1193 unsigned long softirq_disable_ip;
1194 unsigned int softirq_disable_event;
1195 unsigned long softirq_enable_ip;
1196 unsigned int softirq_enable_event;
1197 int hardirq_context;
1198 int softirq_context;
1199 #endif
1200 #ifdef CONFIG_LOCKDEP
1201 # define MAX_LOCK_DEPTH 48UL
1202 u64 curr_chain_key;
1203 int lockdep_depth;
1204 struct held_lock held_locks[MAX_LOCK_DEPTH];
1205 unsigned int lockdep_recursion;
1206 #endif
1207
1208 /* journalling filesystem info */
1209 void *journal_info;
1210
1211 /* stacked block device info */
1212 struct bio *bio_list, **bio_tail;
1213
1214 /* VM state */
1215 struct reclaim_state *reclaim_state;
1216
1217 struct backing_dev_info *backing_dev_info;
1218
1219 struct io_context *io_context;
1220
1221 unsigned long ptrace_message;
1222 siginfo_t *last_siginfo; /* For ptrace use. */
1223 #ifdef CONFIG_TASK_XACCT
1224 /* i/o counters(bytes read/written, #syscalls */
1225 u64 rchar, wchar, syscr, syscw;
1226 #endif
1227 struct task_io_accounting ioac;
1228 #if defined(CONFIG_TASK_XACCT)
1229 u64 acct_rss_mem1; /* accumulated rss usage */
1230 u64 acct_vm_mem1; /* accumulated virtual memory usage */
1231 cputime_t acct_stimexpd;/* stime since last update */
1232 #endif
1233 #ifdef CONFIG_NUMA
1234 struct mempolicy *mempolicy;
1235 short il_next;
1236 #endif
1237 #ifdef CONFIG_CPUSETS
1238 nodemask_t mems_allowed;
1239 int cpuset_mems_generation;
1240 int cpuset_mem_spread_rotor;
1241 #endif
1242 #ifdef CONFIG_CGROUPS
1243 /* Control Group info protected by css_set_lock */
1244 struct css_set *cgroups;
1245 /* cg_list protected by css_set_lock and tsk->alloc_lock */
1246 struct list_head cg_list;
1247 #endif
1248 #ifdef CONFIG_FUTEX
1249 struct robust_list_head __user *robust_list;
1250 #ifdef CONFIG_COMPAT
1251 struct compat_robust_list_head __user *compat_robust_list;
1252 #endif
1253 struct list_head pi_state_list;
1254 struct futex_pi_state *pi_state_cache;
1255 #endif
1256 atomic_t fs_excl; /* holding fs exclusive resources */
1257 struct rcu_head rcu;
1258
1259 /*
1260 * cache last used pipe for splice
1261 */
1262 struct pipe_inode_info *splice_pipe;
1263 #ifdef CONFIG_TASK_DELAY_ACCT
1264 struct task_delay_info *delays;
1265 #endif
1266 #ifdef CONFIG_FAULT_INJECTION
1267 int make_it_fail;
1268 #endif
1269 struct prop_local_single dirties;
1270 #ifdef CONFIG_LATENCYTOP
1271 int latency_record_count;
1272 struct latency_record latency_record[LT_SAVECOUNT];
1273 #endif
1274 };
1275
1276 /*
1277 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1278 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1279 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1280 * values are inverted: lower p->prio value means higher priority.
1281 *
1282 * The MAX_USER_RT_PRIO value allows the actual maximum
1283 * RT priority to be separate from the value exported to
1284 * user-space. This allows kernel threads to set their
1285 * priority to a value higher than any user task. Note:
1286 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1287 */
1288
1289 #define MAX_USER_RT_PRIO 100
1290 #define MAX_RT_PRIO MAX_USER_RT_PRIO
1291
1292 #define MAX_PRIO (MAX_RT_PRIO + 40)
1293 #define DEFAULT_PRIO (MAX_RT_PRIO + 20)
1294
1295 static inline int rt_prio(int prio)
1296 {
1297 if (unlikely(prio < MAX_RT_PRIO))
1298 return 1;
1299 return 0;
1300 }
1301
1302 static inline int rt_task(struct task_struct *p)
1303 {
1304 return rt_prio(p->prio);
1305 }
1306
1307 static inline void set_task_session(struct task_struct *tsk, pid_t session)
1308 {
1309 tsk->signal->__session = session;
1310 }
1311
1312 static inline void set_task_pgrp(struct task_struct *tsk, pid_t pgrp)
1313 {
1314 tsk->signal->__pgrp = pgrp;
1315 }
1316
1317 static inline struct pid *task_pid(struct task_struct *task)
1318 {
1319 return task->pids[PIDTYPE_PID].pid;
1320 }
1321
1322 static inline struct pid *task_tgid(struct task_struct *task)
1323 {
1324 return task->group_leader->pids[PIDTYPE_PID].pid;
1325 }
1326
1327 static inline struct pid *task_pgrp(struct task_struct *task)
1328 {
1329 return task->group_leader->pids[PIDTYPE_PGID].pid;
1330 }
1331
1332 static inline struct pid *task_session(struct task_struct *task)
1333 {
1334 return task->group_leader->pids[PIDTYPE_SID].pid;
1335 }
1336
1337 struct pid_namespace;
1338
1339 /*
1340 * the helpers to get the task's different pids as they are seen
1341 * from various namespaces
1342 *
1343 * task_xid_nr() : global id, i.e. the id seen from the init namespace;
1344 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of
1345 * current.
1346 * task_xid_nr_ns() : id seen from the ns specified;
1347 *
1348 * set_task_vxid() : assigns a virtual id to a task;
1349 *
1350 * see also pid_nr() etc in include/linux/pid.h
1351 */
1352
1353 static inline pid_t task_pid_nr(struct task_struct *tsk)
1354 {
1355 return tsk->pid;
1356 }
1357
1358 pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1359
1360 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1361 {
1362 return pid_vnr(task_pid(tsk));
1363 }
1364
1365
1366 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1367 {
1368 return tsk->tgid;
1369 }
1370
1371 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1372
1373 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1374 {
1375 return pid_vnr(task_tgid(tsk));
1376 }
1377
1378
1379 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1380 {
1381 return tsk->signal->__pgrp;
1382 }
1383
1384 pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1385
1386 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1387 {
1388 return pid_vnr(task_pgrp(tsk));
1389 }
1390
1391
1392 static inline pid_t task_session_nr(struct task_struct *tsk)
1393 {
1394 return tsk->signal->__session;
1395 }
1396
1397 pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1398
1399 static inline pid_t task_session_vnr(struct task_struct *tsk)
1400 {
1401 return pid_vnr(task_session(tsk));
1402 }
1403
1404
1405 /**
1406 * pid_alive - check that a task structure is not stale
1407 * @p: Task structure to be checked.
1408 *
1409 * Test if a process is not yet dead (at most zombie state)
1410 * If pid_alive fails, then pointers within the task structure
1411 * can be stale and must not be dereferenced.
1412 */
1413 static inline int pid_alive(struct task_struct *p)
1414 {
1415 return p->pids[PIDTYPE_PID].pid != NULL;
1416 }
1417
1418 /**
1419 * is_global_init - check if a task structure is init
1420 * @tsk: Task structure to be checked.
1421 *
1422 * Check if a task structure is the first user space task the kernel created.
1423 */
1424 static inline int is_global_init(struct task_struct *tsk)
1425 {
1426 return tsk->pid == 1;
1427 }
1428
1429 /*
1430 * is_container_init:
1431 * check whether in the task is init in its own pid namespace.
1432 */
1433 extern int is_container_init(struct task_struct *tsk);
1434
1435 extern struct pid *cad_pid;
1436
1437 extern void free_task(struct task_struct *tsk);
1438 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1439
1440 extern void __put_task_struct(struct task_struct *t);
1441
1442 static inline void put_task_struct(struct task_struct *t)
1443 {
1444 if (atomic_dec_and_test(&t->usage))
1445 __put_task_struct(t);
1446 }
1447
1448 /*
1449 * Per process flags
1450 */
1451 #define PF_ALIGNWARN 0x00000001 /* Print alignment warning msgs */
1452 /* Not implemented yet, only for 486*/
1453 #define PF_STARTING 0x00000002 /* being created */
1454 #define PF_EXITING 0x00000004 /* getting shut down */
1455 #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */
1456 #define PF_VCPU 0x00000010 /* I'm a virtual CPU */
1457 #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
1458 #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
1459 #define PF_DUMPCORE 0x00000200 /* dumped core */
1460 #define PF_SIGNALED 0x00000400 /* killed by a signal */
1461 #define PF_MEMALLOC 0x00000800 /* Allocating memory */
1462 #define PF_FLUSHER 0x00001000 /* responsible for disk writeback */
1463 #define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
1464 #define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
1465 #define PF_FROZEN 0x00010000 /* frozen for system suspend */
1466 #define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
1467 #define PF_KSWAPD 0x00040000 /* I am kswapd */
1468 #define PF_SWAPOFF 0x00080000 /* I am in swapoff */
1469 #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
1470 #define PF_BORROWED_MM 0x00200000 /* I am a kthread doing use_mm */
1471 #define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */
1472 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1473 #define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */
1474 #define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */
1475 #define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */
1476 #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
1477 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezeable */
1478
1479 /*
1480 * Only the _current_ task can read/write to tsk->flags, but other
1481 * tasks can access tsk->flags in readonly mode for example
1482 * with tsk_used_math (like during threaded core dumping).
1483 * There is however an exception to this rule during ptrace
1484 * or during fork: the ptracer task is allowed to write to the
1485 * child->flags of its traced child (same goes for fork, the parent
1486 * can write to the child->flags), because we're guaranteed the
1487 * child is not running and in turn not changing child->flags
1488 * at the same time the parent does it.
1489 */
1490 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1491 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1492 #define clear_used_math() clear_stopped_child_used_math(current)
1493 #define set_used_math() set_stopped_child_used_math(current)
1494 #define conditional_stopped_child_used_math(condition, child) \
1495 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1496 #define conditional_used_math(condition) \
1497 conditional_stopped_child_used_math(condition, current)
1498 #define copy_to_stopped_child_used_math(child) \
1499 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1500 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1501 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1502 #define used_math() tsk_used_math(current)
1503
1504 #ifdef CONFIG_SMP
1505 extern int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask);
1506 #else
1507 static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1508 {
1509 if (!cpu_isset(0, new_mask))
1510 return -EINVAL;
1511 return 0;
1512 }
1513 #endif
1514
1515 extern unsigned long long sched_clock(void);
1516
1517 /*
1518 * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
1519 * clock constructed from sched_clock():
1520 */
1521 extern unsigned long long cpu_clock(int cpu);
1522
1523 extern unsigned long long
1524 task_sched_runtime(struct task_struct *task);
1525
1526 /* sched_exec is called by processes performing an exec */
1527 #ifdef CONFIG_SMP
1528 extern void sched_exec(void);
1529 #else
1530 #define sched_exec() {}
1531 #endif
1532
1533 extern void sched_clock_idle_sleep_event(void);
1534 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1535
1536 #ifdef CONFIG_HOTPLUG_CPU
1537 extern void idle_task_exit(void);
1538 #else
1539 static inline void idle_task_exit(void) {}
1540 #endif
1541
1542 extern void sched_idle_next(void);
1543
1544 #if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
1545 extern void wake_up_idle_cpu(int cpu);
1546 #else
1547 static inline void wake_up_idle_cpu(int cpu) { }
1548 #endif
1549
1550 #ifdef CONFIG_SCHED_DEBUG
1551 extern unsigned int sysctl_sched_latency;
1552 extern unsigned int sysctl_sched_min_granularity;
1553 extern unsigned int sysctl_sched_wakeup_granularity;
1554 extern unsigned int sysctl_sched_batch_wakeup_granularity;
1555 extern unsigned int sysctl_sched_child_runs_first;
1556 extern unsigned int sysctl_sched_features;
1557 extern unsigned int sysctl_sched_migration_cost;
1558 extern unsigned int sysctl_sched_nr_migrate;
1559
1560 int sched_nr_latency_handler(struct ctl_table *table, int write,
1561 struct file *file, void __user *buffer, size_t *length,
1562 loff_t *ppos);
1563 #endif
1564 extern unsigned int sysctl_sched_rt_period;
1565 extern int sysctl_sched_rt_runtime;
1566
1567 extern unsigned int sysctl_sched_compat_yield;
1568
1569 #ifdef CONFIG_RT_MUTEXES
1570 extern int rt_mutex_getprio(struct task_struct *p);
1571 extern void rt_mutex_setprio(struct task_struct *p, int prio);
1572 extern void rt_mutex_adjust_pi(struct task_struct *p);
1573 #else
1574 static inline int rt_mutex_getprio(struct task_struct *p)
1575 {
1576 return p->normal_prio;
1577 }
1578 # define rt_mutex_adjust_pi(p) do { } while (0)
1579 #endif
1580
1581 extern void set_user_nice(struct task_struct *p, long nice);
1582 extern int task_prio(const struct task_struct *p);
1583 extern int task_nice(const struct task_struct *p);
1584 extern int can_nice(const struct task_struct *p, const int nice);
1585 extern int task_curr(const struct task_struct *p);
1586 extern int idle_cpu(int cpu);
1587 extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1588 extern struct task_struct *idle_task(int cpu);
1589 extern struct task_struct *curr_task(int cpu);
1590 extern void set_curr_task(int cpu, struct task_struct *p);
1591
1592 void yield(void);
1593
1594 /*
1595 * The default (Linux) execution domain.
1596 */
1597 extern struct exec_domain default_exec_domain;
1598
1599 union thread_union {
1600 struct thread_info thread_info;
1601 unsigned long stack[THREAD_SIZE/sizeof(long)];
1602 };
1603
1604 #ifndef __HAVE_ARCH_KSTACK_END
1605 static inline int kstack_end(void *addr)
1606 {
1607 /* Reliable end of stack detection:
1608 * Some APM bios versions misalign the stack
1609 */
1610 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1611 }
1612 #endif
1613
1614 extern union thread_union init_thread_union;
1615 extern struct task_struct init_task;
1616
1617 extern struct mm_struct init_mm;
1618
1619 extern struct pid_namespace init_pid_ns;
1620
1621 /*
1622 * find a task by one of its numerical ids
1623 *
1624 * find_task_by_pid_type_ns():
1625 * it is the most generic call - it finds a task by all id,
1626 * type and namespace specified
1627 * find_task_by_pid_ns():
1628 * finds a task by its pid in the specified namespace
1629 * find_task_by_vpid():
1630 * finds a task by its virtual pid
1631 * find_task_by_pid():
1632 * finds a task by its global pid
1633 *
1634 * see also find_pid() etc in include/linux/pid.h
1635 */
1636
1637 extern struct task_struct *find_task_by_pid_type_ns(int type, int pid,
1638 struct pid_namespace *ns);
1639
1640 extern struct task_struct *find_task_by_pid(pid_t nr);
1641 extern struct task_struct *find_task_by_vpid(pid_t nr);
1642 extern struct task_struct *find_task_by_pid_ns(pid_t nr,
1643 struct pid_namespace *ns);
1644
1645 extern void __set_special_pids(struct pid *pid);
1646
1647 /* per-UID process charging. */
1648 extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
1649 static inline struct user_struct *get_uid(struct user_struct *u)
1650 {
1651 atomic_inc(&u->__count);
1652 return u;
1653 }
1654 extern void free_uid(struct user_struct *);
1655 extern void switch_uid(struct user_struct *);
1656 extern void release_uids(struct user_namespace *ns);
1657
1658 #include <asm/current.h>
1659
1660 extern void do_timer(unsigned long ticks);
1661
1662 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1663 extern int wake_up_process(struct task_struct *tsk);
1664 extern void wake_up_new_task(struct task_struct *tsk,
1665 unsigned long clone_flags);
1666 #ifdef CONFIG_SMP
1667 extern void kick_process(struct task_struct *tsk);
1668 #else
1669 static inline void kick_process(struct task_struct *tsk) { }
1670 #endif
1671 extern void sched_fork(struct task_struct *p, int clone_flags);
1672 extern void sched_dead(struct task_struct *p);
1673
1674 extern int in_group_p(gid_t);
1675 extern int in_egroup_p(gid_t);
1676
1677 extern void proc_caches_init(void);
1678 extern void flush_signals(struct task_struct *);
1679 extern void ignore_signals(struct task_struct *);
1680 extern void flush_signal_handlers(struct task_struct *, int force_default);
1681 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1682
1683 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1684 {
1685 unsigned long flags;
1686 int ret;
1687
1688 spin_lock_irqsave(&tsk->sighand->siglock, flags);
1689 ret = dequeue_signal(tsk, mask, info);
1690 spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1691
1692 return ret;
1693 }
1694
1695 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1696 sigset_t *mask);
1697 extern void unblock_all_signals(void);
1698 extern void release_task(struct task_struct * p);
1699 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1700 extern int force_sigsegv(int, struct task_struct *);
1701 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1702 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1703 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
1704 extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
1705 extern int kill_pgrp(struct pid *pid, int sig, int priv);
1706 extern int kill_pid(struct pid *pid, int sig, int priv);
1707 extern int kill_proc_info(int, struct siginfo *, pid_t);
1708 extern void do_notify_parent(struct task_struct *, int);
1709 extern void force_sig(int, struct task_struct *);
1710 extern void force_sig_specific(int, struct task_struct *);
1711 extern int send_sig(int, struct task_struct *, int);
1712 extern void zap_other_threads(struct task_struct *p);
1713 extern int kill_proc(pid_t, int, int);
1714 extern struct sigqueue *sigqueue_alloc(void);
1715 extern void sigqueue_free(struct sigqueue *);
1716 extern int send_sigqueue(int, struct sigqueue *, struct task_struct *);
1717 extern int send_group_sigqueue(int, struct sigqueue *, struct task_struct *);
1718 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
1719 extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1720
1721 static inline int kill_cad_pid(int sig, int priv)
1722 {
1723 return kill_pid(cad_pid, sig, priv);
1724 }
1725
1726 /* These can be the second arg to send_sig_info/send_group_sig_info. */
1727 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
1728 #define SEND_SIG_PRIV ((struct siginfo *) 1)
1729 #define SEND_SIG_FORCED ((struct siginfo *) 2)
1730
1731 static inline int is_si_special(const struct siginfo *info)
1732 {
1733 return info <= SEND_SIG_FORCED;
1734 }
1735
1736 /* True if we are on the alternate signal stack. */
1737
1738 static inline int on_sig_stack(unsigned long sp)
1739 {
1740 return (sp - current->sas_ss_sp < current->sas_ss_size);
1741 }
1742
1743 static inline int sas_ss_flags(unsigned long sp)
1744 {
1745 return (current->sas_ss_size == 0 ? SS_DISABLE
1746 : on_sig_stack(sp) ? SS_ONSTACK : 0);
1747 }
1748
1749 /*
1750 * Routines for handling mm_structs
1751 */
1752 extern struct mm_struct * mm_alloc(void);
1753
1754 /* mmdrop drops the mm and the page tables */
1755 extern void __mmdrop(struct mm_struct *);
1756 static inline void mmdrop(struct mm_struct * mm)
1757 {
1758 if (unlikely(atomic_dec_and_test(&mm->mm_count)))
1759 __mmdrop(mm);
1760 }
1761
1762 /* mmput gets rid of the mappings and all user-space */
1763 extern void mmput(struct mm_struct *);
1764 /* Grab a reference to a task's mm, if it is not already going away */
1765 extern struct mm_struct *get_task_mm(struct task_struct *task);
1766 /* Remove the current tasks stale references to the old mm_struct */
1767 extern void mm_release(struct task_struct *, struct mm_struct *);
1768
1769 extern int copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1770 extern void flush_thread(void);
1771 extern void exit_thread(void);
1772
1773 extern void exit_files(struct task_struct *);
1774 extern void __cleanup_signal(struct signal_struct *);
1775 extern void __cleanup_sighand(struct sighand_struct *);
1776 extern void exit_itimers(struct signal_struct *);
1777
1778 extern NORET_TYPE void do_group_exit(int);
1779
1780 extern void daemonize(const char *, ...);
1781 extern int allow_signal(int);
1782 extern int disallow_signal(int);
1783
1784 extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1785 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1786 struct task_struct *fork_idle(int);
1787
1788 extern void set_task_comm(struct task_struct *tsk, char *from);
1789 extern char *get_task_comm(char *to, struct task_struct *tsk);
1790
1791 #ifdef CONFIG_SMP
1792 extern void wait_task_inactive(struct task_struct * p);
1793 #else
1794 #define wait_task_inactive(p) do { } while (0)
1795 #endif
1796
1797 #define remove_parent(p) list_del_init(&(p)->sibling)
1798 #define add_parent(p) list_add_tail(&(p)->sibling,&(p)->parent->children)
1799
1800 #define next_task(p) list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
1801
1802 #define for_each_process(p) \
1803 for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1804
1805 /*
1806 * Careful: do_each_thread/while_each_thread is a double loop so
1807 * 'break' will not work as expected - use goto instead.
1808 */
1809 #define do_each_thread(g, t) \
1810 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1811
1812 #define while_each_thread(g, t) \
1813 while ((t = next_thread(t)) != g)
1814
1815 /* de_thread depends on thread_group_leader not being a pid based check */
1816 #define thread_group_leader(p) (p == p->group_leader)
1817
1818 /* Do to the insanities of de_thread it is possible for a process
1819 * to have the pid of the thread group leader without actually being
1820 * the thread group leader. For iteration through the pids in proc
1821 * all we care about is that we have a task with the appropriate
1822 * pid, we don't actually care if we have the right task.
1823 */
1824 static inline int has_group_leader_pid(struct task_struct *p)
1825 {
1826 return p->pid == p->tgid;
1827 }
1828
1829 static inline
1830 int same_thread_group(struct task_struct *p1, struct task_struct *p2)
1831 {
1832 return p1->tgid == p2->tgid;
1833 }
1834
1835 static inline struct task_struct *next_thread(const struct task_struct *p)
1836 {
1837 return list_entry(rcu_dereference(p->thread_group.next),
1838 struct task_struct, thread_group);
1839 }
1840
1841 static inline int thread_group_empty(struct task_struct *p)
1842 {
1843 return list_empty(&p->thread_group);
1844 }
1845
1846 #define delay_group_leader(p) \
1847 (thread_group_leader(p) && !thread_group_empty(p))
1848
1849 /*
1850 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
1851 * subscriptions and synchronises with wait4(). Also used in procfs. Also
1852 * pins the final release of task.io_context. Also protects ->cpuset and
1853 * ->cgroup.subsys[].
1854 *
1855 * Nests both inside and outside of read_lock(&tasklist_lock).
1856 * It must not be nested with write_lock_irq(&tasklist_lock),
1857 * neither inside nor outside.
1858 */
1859 static inline void task_lock(struct task_struct *p)
1860 {
1861 spin_lock(&p->alloc_lock);
1862 }
1863
1864 static inline void task_unlock(struct task_struct *p)
1865 {
1866 spin_unlock(&p->alloc_lock);
1867 }
1868
1869 extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
1870 unsigned long *flags);
1871
1872 static inline void unlock_task_sighand(struct task_struct *tsk,
1873 unsigned long *flags)
1874 {
1875 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
1876 }
1877
1878 #ifndef __HAVE_THREAD_FUNCTIONS
1879
1880 #define task_thread_info(task) ((struct thread_info *)(task)->stack)
1881 #define task_stack_page(task) ((task)->stack)
1882
1883 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
1884 {
1885 *task_thread_info(p) = *task_thread_info(org);
1886 task_thread_info(p)->task = p;
1887 }
1888
1889 static inline unsigned long *end_of_stack(struct task_struct *p)
1890 {
1891 return (unsigned long *)(task_thread_info(p) + 1);
1892 }
1893
1894 #endif
1895
1896 /* set thread flags in other task's structures
1897 * - see asm/thread_info.h for TIF_xxxx flags available
1898 */
1899 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1900 {
1901 set_ti_thread_flag(task_thread_info(tsk), flag);
1902 }
1903
1904 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1905 {
1906 clear_ti_thread_flag(task_thread_info(tsk), flag);
1907 }
1908
1909 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1910 {
1911 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1912 }
1913
1914 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1915 {
1916 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1917 }
1918
1919 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1920 {
1921 return test_ti_thread_flag(task_thread_info(tsk), flag);
1922 }
1923
1924 static inline void set_tsk_need_resched(struct task_struct *tsk)
1925 {
1926 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1927 }
1928
1929 static inline void clear_tsk_need_resched(struct task_struct *tsk)
1930 {
1931 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1932 }
1933
1934 static inline int signal_pending(struct task_struct *p)
1935 {
1936 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1937 }
1938
1939 extern int __fatal_signal_pending(struct task_struct *p);
1940
1941 static inline int fatal_signal_pending(struct task_struct *p)
1942 {
1943 return signal_pending(p) && __fatal_signal_pending(p);
1944 }
1945
1946 static inline int need_resched(void)
1947 {
1948 return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1949 }
1950
1951 /*
1952 * cond_resched() and cond_resched_lock(): latency reduction via
1953 * explicit rescheduling in places that are safe. The return
1954 * value indicates whether a reschedule was done in fact.
1955 * cond_resched_lock() will drop the spinlock before scheduling,
1956 * cond_resched_softirq() will enable bhs before scheduling.
1957 */
1958 #ifdef CONFIG_PREEMPT
1959 static inline int cond_resched(void)
1960 {
1961 return 0;
1962 }
1963 #else
1964 extern int _cond_resched(void);
1965 static inline int cond_resched(void)
1966 {
1967 return _cond_resched();
1968 }
1969 #endif
1970 extern int cond_resched_lock(spinlock_t * lock);
1971 extern int cond_resched_softirq(void);
1972
1973 /*
1974 * Does a critical section need to be broken due to another
1975 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
1976 * but a general need for low latency)
1977 */
1978 static inline int spin_needbreak(spinlock_t *lock)
1979 {
1980 #ifdef CONFIG_PREEMPT
1981 return spin_is_contended(lock);
1982 #else
1983 return 0;
1984 #endif
1985 }
1986
1987 /*
1988 * Reevaluate whether the task has signals pending delivery.
1989 * Wake the task if so.
1990 * This is required every time the blocked sigset_t changes.
1991 * callers must hold sighand->siglock.
1992 */
1993 extern void recalc_sigpending_and_wake(struct task_struct *t);
1994 extern void recalc_sigpending(void);
1995
1996 extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1997
1998 /*
1999 * Wrappers for p->thread_info->cpu access. No-op on UP.
2000 */
2001 #ifdef CONFIG_SMP
2002
2003 static inline unsigned int task_cpu(const struct task_struct *p)
2004 {
2005 return task_thread_info(p)->cpu;
2006 }
2007
2008 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2009
2010 #else
2011
2012 static inline unsigned int task_cpu(const struct task_struct *p)
2013 {
2014 return 0;
2015 }
2016
2017 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2018 {
2019 }
2020
2021 #endif /* CONFIG_SMP */
2022
2023 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
2024 extern void arch_pick_mmap_layout(struct mm_struct *mm);
2025 #else
2026 static inline void arch_pick_mmap_layout(struct mm_struct *mm)
2027 {
2028 mm->mmap_base = TASK_UNMAPPED_BASE;
2029 mm->get_unmapped_area = arch_get_unmapped_area;
2030 mm->unmap_area = arch_unmap_area;
2031 }
2032 #endif
2033
2034 extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
2035 extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
2036
2037 extern int sched_mc_power_savings, sched_smt_power_savings;
2038
2039 extern void normalize_rt_tasks(void);
2040
2041 #ifdef CONFIG_GROUP_SCHED
2042
2043 extern struct task_group init_task_group;
2044
2045 extern struct task_group *sched_create_group(void);
2046 extern void sched_destroy_group(struct task_group *tg);
2047 extern void sched_move_task(struct task_struct *tsk);
2048 #ifdef CONFIG_FAIR_GROUP_SCHED
2049 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2050 extern unsigned long sched_group_shares(struct task_group *tg);
2051 #endif
2052 #ifdef CONFIG_RT_GROUP_SCHED
2053 extern int sched_group_set_rt_runtime(struct task_group *tg,
2054 long rt_runtime_us);
2055 extern long sched_group_rt_runtime(struct task_group *tg);
2056 #endif
2057 #endif
2058
2059 #ifdef CONFIG_TASK_XACCT
2060 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2061 {
2062 tsk->rchar += amt;
2063 }
2064
2065 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2066 {
2067 tsk->wchar += amt;
2068 }
2069
2070 static inline void inc_syscr(struct task_struct *tsk)
2071 {
2072 tsk->syscr++;
2073 }
2074
2075 static inline void inc_syscw(struct task_struct *tsk)
2076 {
2077 tsk->syscw++;
2078 }
2079 #else
2080 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2081 {
2082 }
2083
2084 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2085 {
2086 }
2087
2088 static inline void inc_syscr(struct task_struct *tsk)
2089 {
2090 }
2091
2092 static inline void inc_syscw(struct task_struct *tsk)
2093 {
2094 }
2095 #endif
2096
2097 #ifdef CONFIG_SMP
2098 void migration_init(void);
2099 #else
2100 static inline void migration_init(void)
2101 {
2102 }
2103 #endif
2104
2105 #ifndef TASK_SIZE_OF
2106 #define TASK_SIZE_OF(tsk) TASK_SIZE
2107 #endif
2108
2109 #endif /* __KERNEL__ */
2110
2111 #endif