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