sched.h 52 KB

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  1. #ifndef _LINUX_SCHED_H
  2. #define _LINUX_SCHED_H
  3. #include <linux/auxvec.h> /* For AT_VECTOR_SIZE */
  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. /*
  28. * Scheduling policies
  29. */
  30. #define SCHED_NORMAL 0
  31. #define SCHED_FIFO 1
  32. #define SCHED_RR 2
  33. #define SCHED_BATCH 3
  34. #ifdef __KERNEL__
  35. struct sched_param {
  36. int sched_priority;
  37. };
  38. #include <asm/param.h> /* for HZ */
  39. #include <linux/capability.h>
  40. #include <linux/threads.h>
  41. #include <linux/kernel.h>
  42. #include <linux/types.h>
  43. #include <linux/timex.h>
  44. #include <linux/jiffies.h>
  45. #include <linux/rbtree.h>
  46. #include <linux/thread_info.h>
  47. #include <linux/cpumask.h>
  48. #include <linux/errno.h>
  49. #include <linux/nodemask.h>
  50. #include <asm/system.h>
  51. #include <asm/semaphore.h>
  52. #include <asm/page.h>
  53. #include <asm/ptrace.h>
  54. #include <asm/mmu.h>
  55. #include <asm/cputime.h>
  56. #include <linux/smp.h>
  57. #include <linux/sem.h>
  58. #include <linux/signal.h>
  59. #include <linux/securebits.h>
  60. #include <linux/fs_struct.h>
  61. #include <linux/compiler.h>
  62. #include <linux/completion.h>
  63. #include <linux/pid.h>
  64. #include <linux/percpu.h>
  65. #include <linux/topology.h>
  66. #include <linux/seccomp.h>
  67. #include <linux/rcupdate.h>
  68. #include <linux/futex.h>
  69. #include <linux/rtmutex.h>
  70. #include <linux/time.h>
  71. #include <linux/param.h>
  72. #include <linux/resource.h>
  73. #include <linux/timer.h>
  74. #include <linux/hrtimer.h>
  75. #include <asm/processor.h>
  76. struct exec_domain;
  77. struct futex_pi_state;
  78. /*
  79. * List of flags we want to share for kernel threads,
  80. * if only because they are not used by them anyway.
  81. */
  82. #define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
  83. /*
  84. * These are the constant used to fake the fixed-point load-average
  85. * counting. Some notes:
  86. * - 11 bit fractions expand to 22 bits by the multiplies: this gives
  87. * a load-average precision of 10 bits integer + 11 bits fractional
  88. * - if you want to count load-averages more often, you need more
  89. * precision, or rounding will get you. With 2-second counting freq,
  90. * the EXP_n values would be 1981, 2034 and 2043 if still using only
  91. * 11 bit fractions.
  92. */
  93. extern unsigned long avenrun[]; /* Load averages */
  94. #define FSHIFT 11 /* nr of bits of precision */
  95. #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
  96. #define LOAD_FREQ (5*HZ) /* 5 sec intervals */
  97. #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
  98. #define EXP_5 2014 /* 1/exp(5sec/5min) */
  99. #define EXP_15 2037 /* 1/exp(5sec/15min) */
  100. #define CALC_LOAD(load,exp,n) \
  101. load *= exp; \
  102. load += n*(FIXED_1-exp); \
  103. load >>= FSHIFT;
  104. extern unsigned long total_forks;
  105. extern int nr_threads;
  106. DECLARE_PER_CPU(unsigned long, process_counts);
  107. extern int nr_processes(void);
  108. extern unsigned long nr_running(void);
  109. extern unsigned long nr_uninterruptible(void);
  110. extern unsigned long nr_active(void);
  111. extern unsigned long nr_iowait(void);
  112. extern unsigned long weighted_cpuload(const int cpu);
  113. /*
  114. * Task state bitmask. NOTE! These bits are also
  115. * encoded in fs/proc/array.c: get_task_state().
  116. *
  117. * We have two separate sets of flags: task->state
  118. * is about runnability, while task->exit_state are
  119. * about the task exiting. Confusing, but this way
  120. * modifying one set can't modify the other one by
  121. * mistake.
  122. */
  123. #define TASK_RUNNING 0
  124. #define TASK_INTERRUPTIBLE 1
  125. #define TASK_UNINTERRUPTIBLE 2
  126. #define TASK_STOPPED 4
  127. #define TASK_TRACED 8
  128. /* in tsk->exit_state */
  129. #define EXIT_ZOMBIE 16
  130. #define EXIT_DEAD 32
  131. /* in tsk->state again */
  132. #define TASK_NONINTERACTIVE 64
  133. #define TASK_DEAD 128
  134. #define __set_task_state(tsk, state_value) \
  135. do { (tsk)->state = (state_value); } while (0)
  136. #define set_task_state(tsk, state_value) \
  137. set_mb((tsk)->state, (state_value))
  138. /*
  139. * set_current_state() includes a barrier so that the write of current->state
  140. * is correctly serialised wrt the caller's subsequent test of whether to
  141. * actually sleep:
  142. *
  143. * set_current_state(TASK_UNINTERRUPTIBLE);
  144. * if (do_i_need_to_sleep())
  145. * schedule();
  146. *
  147. * If the caller does not need such serialisation then use __set_current_state()
  148. */
  149. #define __set_current_state(state_value) \
  150. do { current->state = (state_value); } while (0)
  151. #define set_current_state(state_value) \
  152. set_mb(current->state, (state_value))
  153. /* Task command name length */
  154. #define TASK_COMM_LEN 16
  155. #include <linux/spinlock.h>
  156. /*
  157. * This serializes "schedule()" and also protects
  158. * the run-queue from deletions/modifications (but
  159. * _adding_ to the beginning of the run-queue has
  160. * a separate lock).
  161. */
  162. extern rwlock_t tasklist_lock;
  163. extern spinlock_t mmlist_lock;
  164. struct task_struct;
  165. extern void sched_init(void);
  166. extern void sched_init_smp(void);
  167. extern void init_idle(struct task_struct *idle, int cpu);
  168. extern cpumask_t nohz_cpu_mask;
  169. extern void show_state(void);
  170. extern void show_regs(struct pt_regs *);
  171. /*
  172. * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
  173. * task), SP is the stack pointer of the first frame that should be shown in the back
  174. * trace (or NULL if the entire call-chain of the task should be shown).
  175. */
  176. extern void show_stack(struct task_struct *task, unsigned long *sp);
  177. void io_schedule(void);
  178. long io_schedule_timeout(long timeout);
  179. extern void cpu_init (void);
  180. extern void trap_init(void);
  181. extern void update_process_times(int user);
  182. extern void scheduler_tick(void);
  183. #ifdef CONFIG_DETECT_SOFTLOCKUP
  184. extern void softlockup_tick(void);
  185. extern void spawn_softlockup_task(void);
  186. extern void touch_softlockup_watchdog(void);
  187. #else
  188. static inline void softlockup_tick(void)
  189. {
  190. }
  191. static inline void spawn_softlockup_task(void)
  192. {
  193. }
  194. static inline void touch_softlockup_watchdog(void)
  195. {
  196. }
  197. #endif
  198. /* Attach to any functions which should be ignored in wchan output. */
  199. #define __sched __attribute__((__section__(".sched.text")))
  200. /* Is this address in the __sched functions? */
  201. extern int in_sched_functions(unsigned long addr);
  202. #define MAX_SCHEDULE_TIMEOUT LONG_MAX
  203. extern signed long FASTCALL(schedule_timeout(signed long timeout));
  204. extern signed long schedule_timeout_interruptible(signed long timeout);
  205. extern signed long schedule_timeout_uninterruptible(signed long timeout);
  206. asmlinkage void schedule(void);
  207. struct nsproxy;
  208. /* Maximum number of active map areas.. This is a random (large) number */
  209. #define DEFAULT_MAX_MAP_COUNT 65536
  210. extern int sysctl_max_map_count;
  211. #include <linux/aio.h>
  212. extern unsigned long
  213. arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
  214. unsigned long, unsigned long);
  215. extern unsigned long
  216. arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
  217. unsigned long len, unsigned long pgoff,
  218. unsigned long flags);
  219. extern void arch_unmap_area(struct mm_struct *, unsigned long);
  220. extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
  221. #if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
  222. /*
  223. * The mm counters are not protected by its page_table_lock,
  224. * so must be incremented atomically.
  225. */
  226. #define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
  227. #define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
  228. #define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
  229. #define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
  230. #define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
  231. typedef atomic_long_t mm_counter_t;
  232. #else /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
  233. /*
  234. * The mm counters are protected by its page_table_lock,
  235. * so can be incremented directly.
  236. */
  237. #define set_mm_counter(mm, member, value) (mm)->_##member = (value)
  238. #define get_mm_counter(mm, member) ((mm)->_##member)
  239. #define add_mm_counter(mm, member, value) (mm)->_##member += (value)
  240. #define inc_mm_counter(mm, member) (mm)->_##member++
  241. #define dec_mm_counter(mm, member) (mm)->_##member--
  242. typedef unsigned long mm_counter_t;
  243. #endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
  244. #define get_mm_rss(mm) \
  245. (get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
  246. #define update_hiwater_rss(mm) do { \
  247. unsigned long _rss = get_mm_rss(mm); \
  248. if ((mm)->hiwater_rss < _rss) \
  249. (mm)->hiwater_rss = _rss; \
  250. } while (0)
  251. #define update_hiwater_vm(mm) do { \
  252. if ((mm)->hiwater_vm < (mm)->total_vm) \
  253. (mm)->hiwater_vm = (mm)->total_vm; \
  254. } while (0)
  255. struct mm_struct {
  256. struct vm_area_struct * mmap; /* list of VMAs */
  257. struct rb_root mm_rb;
  258. struct vm_area_struct * mmap_cache; /* last find_vma result */
  259. unsigned long (*get_unmapped_area) (struct file *filp,
  260. unsigned long addr, unsigned long len,
  261. unsigned long pgoff, unsigned long flags);
  262. void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
  263. unsigned long mmap_base; /* base of mmap area */
  264. unsigned long task_size; /* size of task vm space */
  265. unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */
  266. unsigned long free_area_cache; /* first hole of size cached_hole_size or larger */
  267. pgd_t * pgd;
  268. atomic_t mm_users; /* How many users with user space? */
  269. atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */
  270. int map_count; /* number of VMAs */
  271. struct rw_semaphore mmap_sem;
  272. spinlock_t page_table_lock; /* Protects page tables and some counters */
  273. struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung
  274. * together off init_mm.mmlist, and are protected
  275. * by mmlist_lock
  276. */
  277. /* Special counters, in some configurations protected by the
  278. * page_table_lock, in other configurations by being atomic.
  279. */
  280. mm_counter_t _file_rss;
  281. mm_counter_t _anon_rss;
  282. unsigned long hiwater_rss; /* High-watermark of RSS usage */
  283. unsigned long hiwater_vm; /* High-water virtual memory usage */
  284. unsigned long total_vm, locked_vm, shared_vm, exec_vm;
  285. unsigned long stack_vm, reserved_vm, def_flags, nr_ptes;
  286. unsigned long start_code, end_code, start_data, end_data;
  287. unsigned long start_brk, brk, start_stack;
  288. unsigned long arg_start, arg_end, env_start, env_end;
  289. unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
  290. unsigned dumpable:2;
  291. cpumask_t cpu_vm_mask;
  292. /* Architecture-specific MM context */
  293. mm_context_t context;
  294. /* Token based thrashing protection. */
  295. unsigned long swap_token_time;
  296. char recent_pagein;
  297. /* coredumping support */
  298. int core_waiters;
  299. struct completion *core_startup_done, core_done;
  300. /* aio bits */
  301. rwlock_t ioctx_list_lock;
  302. struct kioctx *ioctx_list;
  303. };
  304. struct sighand_struct {
  305. atomic_t count;
  306. struct k_sigaction action[_NSIG];
  307. spinlock_t siglock;
  308. };
  309. struct pacct_struct {
  310. int ac_flag;
  311. long ac_exitcode;
  312. unsigned long ac_mem;
  313. cputime_t ac_utime, ac_stime;
  314. unsigned long ac_minflt, ac_majflt;
  315. };
  316. /*
  317. * NOTE! "signal_struct" does not have it's own
  318. * locking, because a shared signal_struct always
  319. * implies a shared sighand_struct, so locking
  320. * sighand_struct is always a proper superset of
  321. * the locking of signal_struct.
  322. */
  323. struct signal_struct {
  324. atomic_t count;
  325. atomic_t live;
  326. wait_queue_head_t wait_chldexit; /* for wait4() */
  327. /* current thread group signal load-balancing target: */
  328. struct task_struct *curr_target;
  329. /* shared signal handling: */
  330. struct sigpending shared_pending;
  331. /* thread group exit support */
  332. int group_exit_code;
  333. /* overloaded:
  334. * - notify group_exit_task when ->count is equal to notify_count
  335. * - everyone except group_exit_task is stopped during signal delivery
  336. * of fatal signals, group_exit_task processes the signal.
  337. */
  338. struct task_struct *group_exit_task;
  339. int notify_count;
  340. /* thread group stop support, overloads group_exit_code too */
  341. int group_stop_count;
  342. unsigned int flags; /* see SIGNAL_* flags below */
  343. /* POSIX.1b Interval Timers */
  344. struct list_head posix_timers;
  345. /* ITIMER_REAL timer for the process */
  346. struct hrtimer real_timer;
  347. struct task_struct *tsk;
  348. ktime_t it_real_incr;
  349. /* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
  350. cputime_t it_prof_expires, it_virt_expires;
  351. cputime_t it_prof_incr, it_virt_incr;
  352. /* job control IDs */
  353. pid_t pgrp;
  354. pid_t tty_old_pgrp;
  355. pid_t session;
  356. /* boolean value for session group leader */
  357. int leader;
  358. struct tty_struct *tty; /* NULL if no tty */
  359. /*
  360. * Cumulative resource counters for dead threads in the group,
  361. * and for reaped dead child processes forked by this group.
  362. * Live threads maintain their own counters and add to these
  363. * in __exit_signal, except for the group leader.
  364. */
  365. cputime_t utime, stime, cutime, cstime;
  366. unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
  367. unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
  368. /*
  369. * Cumulative ns of scheduled CPU time for dead threads in the
  370. * group, not including a zombie group leader. (This only differs
  371. * from jiffies_to_ns(utime + stime) if sched_clock uses something
  372. * other than jiffies.)
  373. */
  374. unsigned long long sched_time;
  375. /*
  376. * We don't bother to synchronize most readers of this at all,
  377. * because there is no reader checking a limit that actually needs
  378. * to get both rlim_cur and rlim_max atomically, and either one
  379. * alone is a single word that can safely be read normally.
  380. * getrlimit/setrlimit use task_lock(current->group_leader) to
  381. * protect this instead of the siglock, because they really
  382. * have no need to disable irqs.
  383. */
  384. struct rlimit rlim[RLIM_NLIMITS];
  385. struct list_head cpu_timers[3];
  386. /* keep the process-shared keyrings here so that they do the right
  387. * thing in threads created with CLONE_THREAD */
  388. #ifdef CONFIG_KEYS
  389. struct key *session_keyring; /* keyring inherited over fork */
  390. struct key *process_keyring; /* keyring private to this process */
  391. #endif
  392. #ifdef CONFIG_BSD_PROCESS_ACCT
  393. struct pacct_struct pacct; /* per-process accounting information */
  394. #endif
  395. #ifdef CONFIG_TASKSTATS
  396. spinlock_t stats_lock;
  397. struct taskstats *stats;
  398. #endif
  399. };
  400. /* Context switch must be unlocked if interrupts are to be enabled */
  401. #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
  402. # define __ARCH_WANT_UNLOCKED_CTXSW
  403. #endif
  404. /*
  405. * Bits in flags field of signal_struct.
  406. */
  407. #define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */
  408. #define SIGNAL_STOP_DEQUEUED 0x00000002 /* stop signal dequeued */
  409. #define SIGNAL_STOP_CONTINUED 0x00000004 /* SIGCONT since WCONTINUED reap */
  410. #define SIGNAL_GROUP_EXIT 0x00000008 /* group exit in progress */
  411. /*
  412. * Priority of a process goes from 0..MAX_PRIO-1, valid RT
  413. * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
  414. * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
  415. * values are inverted: lower p->prio value means higher priority.
  416. *
  417. * The MAX_USER_RT_PRIO value allows the actual maximum
  418. * RT priority to be separate from the value exported to
  419. * user-space. This allows kernel threads to set their
  420. * priority to a value higher than any user task. Note:
  421. * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
  422. */
  423. #define MAX_USER_RT_PRIO 100
  424. #define MAX_RT_PRIO MAX_USER_RT_PRIO
  425. #define MAX_PRIO (MAX_RT_PRIO + 40)
  426. #define rt_prio(prio) unlikely((prio) < MAX_RT_PRIO)
  427. #define rt_task(p) rt_prio((p)->prio)
  428. #define batch_task(p) (unlikely((p)->policy == SCHED_BATCH))
  429. #define is_rt_policy(p) ((p) != SCHED_NORMAL && (p) != SCHED_BATCH)
  430. #define has_rt_policy(p) unlikely(is_rt_policy((p)->policy))
  431. /*
  432. * Some day this will be a full-fledged user tracking system..
  433. */
  434. struct user_struct {
  435. atomic_t __count; /* reference count */
  436. atomic_t processes; /* How many processes does this user have? */
  437. atomic_t files; /* How many open files does this user have? */
  438. atomic_t sigpending; /* How many pending signals does this user have? */
  439. #ifdef CONFIG_INOTIFY_USER
  440. atomic_t inotify_watches; /* How many inotify watches does this user have? */
  441. atomic_t inotify_devs; /* How many inotify devs does this user have opened? */
  442. #endif
  443. /* protected by mq_lock */
  444. unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
  445. unsigned long locked_shm; /* How many pages of mlocked shm ? */
  446. #ifdef CONFIG_KEYS
  447. struct key *uid_keyring; /* UID specific keyring */
  448. struct key *session_keyring; /* UID's default session keyring */
  449. #endif
  450. /* Hash table maintenance information */
  451. struct list_head uidhash_list;
  452. uid_t uid;
  453. };
  454. extern struct user_struct *find_user(uid_t);
  455. extern struct user_struct root_user;
  456. #define INIT_USER (&root_user)
  457. struct backing_dev_info;
  458. struct reclaim_state;
  459. #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
  460. struct sched_info {
  461. /* cumulative counters */
  462. unsigned long cpu_time, /* time spent on the cpu */
  463. run_delay, /* time spent waiting on a runqueue */
  464. pcnt; /* # of timeslices run on this cpu */
  465. /* timestamps */
  466. unsigned long last_arrival, /* when we last ran on a cpu */
  467. last_queued; /* when we were last queued to run */
  468. };
  469. #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
  470. #ifdef CONFIG_SCHEDSTATS
  471. extern struct file_operations proc_schedstat_operations;
  472. #endif /* CONFIG_SCHEDSTATS */
  473. #ifdef CONFIG_TASK_DELAY_ACCT
  474. struct task_delay_info {
  475. spinlock_t lock;
  476. unsigned int flags; /* Private per-task flags */
  477. /* For each stat XXX, add following, aligned appropriately
  478. *
  479. * struct timespec XXX_start, XXX_end;
  480. * u64 XXX_delay;
  481. * u32 XXX_count;
  482. *
  483. * Atomicity of updates to XXX_delay, XXX_count protected by
  484. * single lock above (split into XXX_lock if contention is an issue).
  485. */
  486. /*
  487. * XXX_count is incremented on every XXX operation, the delay
  488. * associated with the operation is added to XXX_delay.
  489. * XXX_delay contains the accumulated delay time in nanoseconds.
  490. */
  491. struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */
  492. u64 blkio_delay; /* wait for sync block io completion */
  493. u64 swapin_delay; /* wait for swapin block io completion */
  494. u32 blkio_count; /* total count of the number of sync block */
  495. /* io operations performed */
  496. u32 swapin_count; /* total count of the number of swapin block */
  497. /* io operations performed */
  498. };
  499. #endif /* CONFIG_TASK_DELAY_ACCT */
  500. static inline int sched_info_on(void)
  501. {
  502. #ifdef CONFIG_SCHEDSTATS
  503. return 1;
  504. #elif defined(CONFIG_TASK_DELAY_ACCT)
  505. extern int delayacct_on;
  506. return delayacct_on;
  507. #else
  508. return 0;
  509. #endif
  510. }
  511. enum idle_type
  512. {
  513. SCHED_IDLE,
  514. NOT_IDLE,
  515. NEWLY_IDLE,
  516. MAX_IDLE_TYPES
  517. };
  518. /*
  519. * sched-domains (multiprocessor balancing) declarations:
  520. */
  521. #define SCHED_LOAD_SCALE 128UL /* increase resolution of load */
  522. #ifdef CONFIG_SMP
  523. #define SD_LOAD_BALANCE 1 /* Do load balancing on this domain. */
  524. #define SD_BALANCE_NEWIDLE 2 /* Balance when about to become idle */
  525. #define SD_BALANCE_EXEC 4 /* Balance on exec */
  526. #define SD_BALANCE_FORK 8 /* Balance on fork, clone */
  527. #define SD_WAKE_IDLE 16 /* Wake to idle CPU on task wakeup */
  528. #define SD_WAKE_AFFINE 32 /* Wake task to waking CPU */
  529. #define SD_WAKE_BALANCE 64 /* Perform balancing at task wakeup */
  530. #define SD_SHARE_CPUPOWER 128 /* Domain members share cpu power */
  531. #define SD_POWERSAVINGS_BALANCE 256 /* Balance for power savings */
  532. #define BALANCE_FOR_POWER ((sched_mc_power_savings || sched_smt_power_savings) \
  533. ? SD_POWERSAVINGS_BALANCE : 0)
  534. struct sched_group {
  535. struct sched_group *next; /* Must be a circular list */
  536. cpumask_t cpumask;
  537. /*
  538. * CPU power of this group, SCHED_LOAD_SCALE being max power for a
  539. * single CPU. This is read only (except for setup, hotplug CPU).
  540. */
  541. unsigned long cpu_power;
  542. };
  543. struct sched_domain {
  544. /* These fields must be setup */
  545. struct sched_domain *parent; /* top domain must be null terminated */
  546. struct sched_group *groups; /* the balancing groups of the domain */
  547. cpumask_t span; /* span of all CPUs in this domain */
  548. unsigned long min_interval; /* Minimum balance interval ms */
  549. unsigned long max_interval; /* Maximum balance interval ms */
  550. unsigned int busy_factor; /* less balancing by factor if busy */
  551. unsigned int imbalance_pct; /* No balance until over watermark */
  552. unsigned long long cache_hot_time; /* Task considered cache hot (ns) */
  553. unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */
  554. unsigned int per_cpu_gain; /* CPU % gained by adding domain cpus */
  555. unsigned int busy_idx;
  556. unsigned int idle_idx;
  557. unsigned int newidle_idx;
  558. unsigned int wake_idx;
  559. unsigned int forkexec_idx;
  560. int flags; /* See SD_* */
  561. /* Runtime fields. */
  562. unsigned long last_balance; /* init to jiffies. units in jiffies */
  563. unsigned int balance_interval; /* initialise to 1. units in ms. */
  564. unsigned int nr_balance_failed; /* initialise to 0 */
  565. #ifdef CONFIG_SCHEDSTATS
  566. /* load_balance() stats */
  567. unsigned long lb_cnt[MAX_IDLE_TYPES];
  568. unsigned long lb_failed[MAX_IDLE_TYPES];
  569. unsigned long lb_balanced[MAX_IDLE_TYPES];
  570. unsigned long lb_imbalance[MAX_IDLE_TYPES];
  571. unsigned long lb_gained[MAX_IDLE_TYPES];
  572. unsigned long lb_hot_gained[MAX_IDLE_TYPES];
  573. unsigned long lb_nobusyg[MAX_IDLE_TYPES];
  574. unsigned long lb_nobusyq[MAX_IDLE_TYPES];
  575. /* Active load balancing */
  576. unsigned long alb_cnt;
  577. unsigned long alb_failed;
  578. unsigned long alb_pushed;
  579. /* SD_BALANCE_EXEC stats */
  580. unsigned long sbe_cnt;
  581. unsigned long sbe_balanced;
  582. unsigned long sbe_pushed;
  583. /* SD_BALANCE_FORK stats */
  584. unsigned long sbf_cnt;
  585. unsigned long sbf_balanced;
  586. unsigned long sbf_pushed;
  587. /* try_to_wake_up() stats */
  588. unsigned long ttwu_wake_remote;
  589. unsigned long ttwu_move_affine;
  590. unsigned long ttwu_move_balance;
  591. #endif
  592. };
  593. extern int partition_sched_domains(cpumask_t *partition1,
  594. cpumask_t *partition2);
  595. /*
  596. * Maximum cache size the migration-costs auto-tuning code will
  597. * search from:
  598. */
  599. extern unsigned int max_cache_size;
  600. #endif /* CONFIG_SMP */
  601. struct io_context; /* See blkdev.h */
  602. struct cpuset;
  603. #define NGROUPS_SMALL 32
  604. #define NGROUPS_PER_BLOCK ((int)(PAGE_SIZE / sizeof(gid_t)))
  605. struct group_info {
  606. int ngroups;
  607. atomic_t usage;
  608. gid_t small_block[NGROUPS_SMALL];
  609. int nblocks;
  610. gid_t *blocks[0];
  611. };
  612. /*
  613. * get_group_info() must be called with the owning task locked (via task_lock())
  614. * when task != current. The reason being that the vast majority of callers are
  615. * looking at current->group_info, which can not be changed except by the
  616. * current task. Changing current->group_info requires the task lock, too.
  617. */
  618. #define get_group_info(group_info) do { \
  619. atomic_inc(&(group_info)->usage); \
  620. } while (0)
  621. #define put_group_info(group_info) do { \
  622. if (atomic_dec_and_test(&(group_info)->usage)) \
  623. groups_free(group_info); \
  624. } while (0)
  625. extern struct group_info *groups_alloc(int gidsetsize);
  626. extern void groups_free(struct group_info *group_info);
  627. extern int set_current_groups(struct group_info *group_info);
  628. extern int groups_search(struct group_info *group_info, gid_t grp);
  629. /* access the groups "array" with this macro */
  630. #define GROUP_AT(gi, i) \
  631. ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
  632. #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
  633. extern void prefetch_stack(struct task_struct *t);
  634. #else
  635. static inline void prefetch_stack(struct task_struct *t) { }
  636. #endif
  637. struct audit_context; /* See audit.c */
  638. struct mempolicy;
  639. struct pipe_inode_info;
  640. struct uts_namespace;
  641. enum sleep_type {
  642. SLEEP_NORMAL,
  643. SLEEP_NONINTERACTIVE,
  644. SLEEP_INTERACTIVE,
  645. SLEEP_INTERRUPTED,
  646. };
  647. struct prio_array;
  648. struct task_struct {
  649. volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
  650. struct thread_info *thread_info;
  651. atomic_t usage;
  652. unsigned long flags; /* per process flags, defined below */
  653. unsigned long ptrace;
  654. int lock_depth; /* BKL lock depth */
  655. #ifdef CONFIG_SMP
  656. #ifdef __ARCH_WANT_UNLOCKED_CTXSW
  657. int oncpu;
  658. #endif
  659. #endif
  660. int load_weight; /* for niceness load balancing purposes */
  661. int prio, static_prio, normal_prio;
  662. struct list_head run_list;
  663. struct prio_array *array;
  664. unsigned short ioprio;
  665. #ifdef CONFIG_BLK_DEV_IO_TRACE
  666. unsigned int btrace_seq;
  667. #endif
  668. unsigned long sleep_avg;
  669. unsigned long long timestamp, last_ran;
  670. unsigned long long sched_time; /* sched_clock time spent running */
  671. enum sleep_type sleep_type;
  672. unsigned long policy;
  673. cpumask_t cpus_allowed;
  674. unsigned int time_slice, first_time_slice;
  675. #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
  676. struct sched_info sched_info;
  677. #endif
  678. struct list_head tasks;
  679. /*
  680. * ptrace_list/ptrace_children forms the list of my children
  681. * that were stolen by a ptracer.
  682. */
  683. struct list_head ptrace_children;
  684. struct list_head ptrace_list;
  685. struct mm_struct *mm, *active_mm;
  686. /* task state */
  687. struct linux_binfmt *binfmt;
  688. long exit_state;
  689. int exit_code, exit_signal;
  690. int pdeath_signal; /* The signal sent when the parent dies */
  691. /* ??? */
  692. unsigned long personality;
  693. unsigned did_exec:1;
  694. pid_t pid;
  695. pid_t tgid;
  696. #ifdef CONFIG_CC_STACKPROTECTOR
  697. /* Canary value for the -fstack-protector gcc feature */
  698. unsigned long stack_canary;
  699. #endif
  700. /*
  701. * pointers to (original) parent process, youngest child, younger sibling,
  702. * older sibling, respectively. (p->father can be replaced with
  703. * p->parent->pid)
  704. */
  705. struct task_struct *real_parent; /* real parent process (when being debugged) */
  706. struct task_struct *parent; /* parent process */
  707. /*
  708. * children/sibling forms the list of my children plus the
  709. * tasks I'm ptracing.
  710. */
  711. struct list_head children; /* list of my children */
  712. struct list_head sibling; /* linkage in my parent's children list */
  713. struct task_struct *group_leader; /* threadgroup leader */
  714. /* PID/PID hash table linkage. */
  715. struct pid_link pids[PIDTYPE_MAX];
  716. struct list_head thread_group;
  717. struct completion *vfork_done; /* for vfork() */
  718. int __user *set_child_tid; /* CLONE_CHILD_SETTID */
  719. int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
  720. unsigned long rt_priority;
  721. cputime_t utime, stime;
  722. unsigned long nvcsw, nivcsw; /* context switch counts */
  723. struct timespec start_time;
  724. /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
  725. unsigned long min_flt, maj_flt;
  726. cputime_t it_prof_expires, it_virt_expires;
  727. unsigned long long it_sched_expires;
  728. struct list_head cpu_timers[3];
  729. /* process credentials */
  730. uid_t uid,euid,suid,fsuid;
  731. gid_t gid,egid,sgid,fsgid;
  732. struct group_info *group_info;
  733. kernel_cap_t cap_effective, cap_inheritable, cap_permitted;
  734. unsigned keep_capabilities:1;
  735. struct user_struct *user;
  736. #ifdef CONFIG_KEYS
  737. struct key *request_key_auth; /* assumed request_key authority */
  738. struct key *thread_keyring; /* keyring private to this thread */
  739. unsigned char jit_keyring; /* default keyring to attach requested keys to */
  740. #endif
  741. /*
  742. * fpu_counter contains the number of consecutive context switches
  743. * that the FPU is used. If this is over a threshold, the lazy fpu
  744. * saving becomes unlazy to save the trap. This is an unsigned char
  745. * so that after 256 times the counter wraps and the behavior turns
  746. * lazy again; this to deal with bursty apps that only use FPU for
  747. * a short time
  748. */
  749. unsigned char fpu_counter;
  750. int oomkilladj; /* OOM kill score adjustment (bit shift). */
  751. char comm[TASK_COMM_LEN]; /* executable name excluding path
  752. - access with [gs]et_task_comm (which lock
  753. it with task_lock())
  754. - initialized normally by flush_old_exec */
  755. /* file system info */
  756. int link_count, total_link_count;
  757. #ifdef CONFIG_SYSVIPC
  758. /* ipc stuff */
  759. struct sysv_sem sysvsem;
  760. #endif
  761. /* CPU-specific state of this task */
  762. struct thread_struct thread;
  763. /* filesystem information */
  764. struct fs_struct *fs;
  765. /* open file information */
  766. struct files_struct *files;
  767. /* namespaces */
  768. struct nsproxy *nsproxy;
  769. /* signal handlers */
  770. struct signal_struct *signal;
  771. struct sighand_struct *sighand;
  772. sigset_t blocked, real_blocked;
  773. sigset_t saved_sigmask; /* To be restored with TIF_RESTORE_SIGMASK */
  774. struct sigpending pending;
  775. unsigned long sas_ss_sp;
  776. size_t sas_ss_size;
  777. int (*notifier)(void *priv);
  778. void *notifier_data;
  779. sigset_t *notifier_mask;
  780. void *security;
  781. struct audit_context *audit_context;
  782. seccomp_t seccomp;
  783. /* Thread group tracking */
  784. u32 parent_exec_id;
  785. u32 self_exec_id;
  786. /* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
  787. spinlock_t alloc_lock;
  788. /* Protection of the PI data structures: */
  789. spinlock_t pi_lock;
  790. #ifdef CONFIG_RT_MUTEXES
  791. /* PI waiters blocked on a rt_mutex held by this task */
  792. struct plist_head pi_waiters;
  793. /* Deadlock detection and priority inheritance handling */
  794. struct rt_mutex_waiter *pi_blocked_on;
  795. #endif
  796. #ifdef CONFIG_DEBUG_MUTEXES
  797. /* mutex deadlock detection */
  798. struct mutex_waiter *blocked_on;
  799. #endif
  800. #ifdef CONFIG_TRACE_IRQFLAGS
  801. unsigned int irq_events;
  802. int hardirqs_enabled;
  803. unsigned long hardirq_enable_ip;
  804. unsigned int hardirq_enable_event;
  805. unsigned long hardirq_disable_ip;
  806. unsigned int hardirq_disable_event;
  807. int softirqs_enabled;
  808. unsigned long softirq_disable_ip;
  809. unsigned int softirq_disable_event;
  810. unsigned long softirq_enable_ip;
  811. unsigned int softirq_enable_event;
  812. int hardirq_context;
  813. int softirq_context;
  814. #endif
  815. #ifdef CONFIG_LOCKDEP
  816. # define MAX_LOCK_DEPTH 30UL
  817. u64 curr_chain_key;
  818. int lockdep_depth;
  819. struct held_lock held_locks[MAX_LOCK_DEPTH];
  820. unsigned int lockdep_recursion;
  821. #endif
  822. /* journalling filesystem info */
  823. void *journal_info;
  824. /* VM state */
  825. struct reclaim_state *reclaim_state;
  826. struct backing_dev_info *backing_dev_info;
  827. struct io_context *io_context;
  828. unsigned long ptrace_message;
  829. siginfo_t *last_siginfo; /* For ptrace use. */
  830. /*
  831. * current io wait handle: wait queue entry to use for io waits
  832. * If this thread is processing aio, this points at the waitqueue
  833. * inside the currently handled kiocb. It may be NULL (i.e. default
  834. * to a stack based synchronous wait) if its doing sync IO.
  835. */
  836. wait_queue_t *io_wait;
  837. /* i/o counters(bytes read/written, #syscalls */
  838. u64 rchar, wchar, syscr, syscw;
  839. #if defined(CONFIG_TASK_XACCT)
  840. u64 acct_rss_mem1; /* accumulated rss usage */
  841. u64 acct_vm_mem1; /* accumulated virtual memory usage */
  842. cputime_t acct_stimexpd;/* stime since last update */
  843. #endif
  844. #ifdef CONFIG_NUMA
  845. struct mempolicy *mempolicy;
  846. short il_next;
  847. #endif
  848. #ifdef CONFIG_CPUSETS
  849. struct cpuset *cpuset;
  850. nodemask_t mems_allowed;
  851. int cpuset_mems_generation;
  852. int cpuset_mem_spread_rotor;
  853. #endif
  854. struct robust_list_head __user *robust_list;
  855. #ifdef CONFIG_COMPAT
  856. struct compat_robust_list_head __user *compat_robust_list;
  857. #endif
  858. struct list_head pi_state_list;
  859. struct futex_pi_state *pi_state_cache;
  860. atomic_t fs_excl; /* holding fs exclusive resources */
  861. struct rcu_head rcu;
  862. /*
  863. * cache last used pipe for splice
  864. */
  865. struct pipe_inode_info *splice_pipe;
  866. #ifdef CONFIG_TASK_DELAY_ACCT
  867. struct task_delay_info *delays;
  868. #endif
  869. };
  870. static inline pid_t process_group(struct task_struct *tsk)
  871. {
  872. return tsk->signal->pgrp;
  873. }
  874. static inline struct pid *task_pid(struct task_struct *task)
  875. {
  876. return task->pids[PIDTYPE_PID].pid;
  877. }
  878. static inline struct pid *task_tgid(struct task_struct *task)
  879. {
  880. return task->group_leader->pids[PIDTYPE_PID].pid;
  881. }
  882. static inline struct pid *task_pgrp(struct task_struct *task)
  883. {
  884. return task->group_leader->pids[PIDTYPE_PGID].pid;
  885. }
  886. static inline struct pid *task_session(struct task_struct *task)
  887. {
  888. return task->group_leader->pids[PIDTYPE_SID].pid;
  889. }
  890. /**
  891. * pid_alive - check that a task structure is not stale
  892. * @p: Task structure to be checked.
  893. *
  894. * Test if a process is not yet dead (at most zombie state)
  895. * If pid_alive fails, then pointers within the task structure
  896. * can be stale and must not be dereferenced.
  897. */
  898. static inline int pid_alive(struct task_struct *p)
  899. {
  900. return p->pids[PIDTYPE_PID].pid != NULL;
  901. }
  902. /**
  903. * is_init - check if a task structure is the first user space
  904. * task the kernel created.
  905. * @p: Task structure to be checked.
  906. */
  907. static inline int is_init(struct task_struct *tsk)
  908. {
  909. return tsk->pid == 1;
  910. }
  911. extern void free_task(struct task_struct *tsk);
  912. #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
  913. extern void __put_task_struct(struct task_struct *t);
  914. static inline void put_task_struct(struct task_struct *t)
  915. {
  916. if (atomic_dec_and_test(&t->usage))
  917. __put_task_struct(t);
  918. }
  919. /*
  920. * Per process flags
  921. */
  922. #define PF_ALIGNWARN 0x00000001 /* Print alignment warning msgs */
  923. /* Not implemented yet, only for 486*/
  924. #define PF_STARTING 0x00000002 /* being created */
  925. #define PF_EXITING 0x00000004 /* getting shut down */
  926. #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
  927. #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
  928. #define PF_DUMPCORE 0x00000200 /* dumped core */
  929. #define PF_SIGNALED 0x00000400 /* killed by a signal */
  930. #define PF_MEMALLOC 0x00000800 /* Allocating memory */
  931. #define PF_FLUSHER 0x00001000 /* responsible for disk writeback */
  932. #define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
  933. #define PF_FREEZE 0x00004000 /* this task is being frozen for suspend now */
  934. #define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
  935. #define PF_FROZEN 0x00010000 /* frozen for system suspend */
  936. #define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
  937. #define PF_KSWAPD 0x00040000 /* I am kswapd */
  938. #define PF_SWAPOFF 0x00080000 /* I am in swapoff */
  939. #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
  940. #define PF_BORROWED_MM 0x00200000 /* I am a kthread doing use_mm */
  941. #define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */
  942. #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
  943. #define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */
  944. #define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */
  945. #define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */
  946. #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
  947. /*
  948. * Only the _current_ task can read/write to tsk->flags, but other
  949. * tasks can access tsk->flags in readonly mode for example
  950. * with tsk_used_math (like during threaded core dumping).
  951. * There is however an exception to this rule during ptrace
  952. * or during fork: the ptracer task is allowed to write to the
  953. * child->flags of its traced child (same goes for fork, the parent
  954. * can write to the child->flags), because we're guaranteed the
  955. * child is not running and in turn not changing child->flags
  956. * at the same time the parent does it.
  957. */
  958. #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
  959. #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
  960. #define clear_used_math() clear_stopped_child_used_math(current)
  961. #define set_used_math() set_stopped_child_used_math(current)
  962. #define conditional_stopped_child_used_math(condition, child) \
  963. do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
  964. #define conditional_used_math(condition) \
  965. conditional_stopped_child_used_math(condition, current)
  966. #define copy_to_stopped_child_used_math(child) \
  967. do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
  968. /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
  969. #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
  970. #define used_math() tsk_used_math(current)
  971. #ifdef CONFIG_SMP
  972. extern int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask);
  973. #else
  974. static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
  975. {
  976. if (!cpu_isset(0, new_mask))
  977. return -EINVAL;
  978. return 0;
  979. }
  980. #endif
  981. extern unsigned long long sched_clock(void);
  982. extern unsigned long long
  983. current_sched_time(const struct task_struct *current_task);
  984. /* sched_exec is called by processes performing an exec */
  985. #ifdef CONFIG_SMP
  986. extern void sched_exec(void);
  987. #else
  988. #define sched_exec() {}
  989. #endif
  990. #ifdef CONFIG_HOTPLUG_CPU
  991. extern void idle_task_exit(void);
  992. #else
  993. static inline void idle_task_exit(void) {}
  994. #endif
  995. extern void sched_idle_next(void);
  996. #ifdef CONFIG_RT_MUTEXES
  997. extern int rt_mutex_getprio(struct task_struct *p);
  998. extern void rt_mutex_setprio(struct task_struct *p, int prio);
  999. extern void rt_mutex_adjust_pi(struct task_struct *p);
  1000. #else
  1001. static inline int rt_mutex_getprio(struct task_struct *p)
  1002. {
  1003. return p->normal_prio;
  1004. }
  1005. # define rt_mutex_adjust_pi(p) do { } while (0)
  1006. #endif
  1007. extern void set_user_nice(struct task_struct *p, long nice);
  1008. extern int task_prio(const struct task_struct *p);
  1009. extern int task_nice(const struct task_struct *p);
  1010. extern int can_nice(const struct task_struct *p, const int nice);
  1011. extern int task_curr(const struct task_struct *p);
  1012. extern int idle_cpu(int cpu);
  1013. extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
  1014. extern struct task_struct *idle_task(int cpu);
  1015. extern struct task_struct *curr_task(int cpu);
  1016. extern void set_curr_task(int cpu, struct task_struct *p);
  1017. void yield(void);
  1018. /*
  1019. * The default (Linux) execution domain.
  1020. */
  1021. extern struct exec_domain default_exec_domain;
  1022. union thread_union {
  1023. struct thread_info thread_info;
  1024. unsigned long stack[THREAD_SIZE/sizeof(long)];
  1025. };
  1026. #ifndef __HAVE_ARCH_KSTACK_END
  1027. static inline int kstack_end(void *addr)
  1028. {
  1029. /* Reliable end of stack detection:
  1030. * Some APM bios versions misalign the stack
  1031. */
  1032. return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
  1033. }
  1034. #endif
  1035. extern union thread_union init_thread_union;
  1036. extern struct task_struct init_task;
  1037. extern struct mm_struct init_mm;
  1038. #define find_task_by_pid(nr) find_task_by_pid_type(PIDTYPE_PID, nr)
  1039. extern struct task_struct *find_task_by_pid_type(int type, int pid);
  1040. extern void set_special_pids(pid_t session, pid_t pgrp);
  1041. extern void __set_special_pids(pid_t session, pid_t pgrp);
  1042. /* per-UID process charging. */
  1043. extern struct user_struct * alloc_uid(uid_t);
  1044. static inline struct user_struct *get_uid(struct user_struct *u)
  1045. {
  1046. atomic_inc(&u->__count);
  1047. return u;
  1048. }
  1049. extern void free_uid(struct user_struct *);
  1050. extern void switch_uid(struct user_struct *);
  1051. #include <asm/current.h>
  1052. extern void do_timer(unsigned long ticks);
  1053. extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state));
  1054. extern int FASTCALL(wake_up_process(struct task_struct * tsk));
  1055. extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
  1056. unsigned long clone_flags));
  1057. #ifdef CONFIG_SMP
  1058. extern void kick_process(struct task_struct *tsk);
  1059. #else
  1060. static inline void kick_process(struct task_struct *tsk) { }
  1061. #endif
  1062. extern void FASTCALL(sched_fork(struct task_struct * p, int clone_flags));
  1063. extern void FASTCALL(sched_exit(struct task_struct * p));
  1064. extern int in_group_p(gid_t);
  1065. extern int in_egroup_p(gid_t);
  1066. extern void proc_caches_init(void);
  1067. extern void flush_signals(struct task_struct *);
  1068. extern void flush_signal_handlers(struct task_struct *, int force_default);
  1069. extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
  1070. static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
  1071. {
  1072. unsigned long flags;
  1073. int ret;
  1074. spin_lock_irqsave(&tsk->sighand->siglock, flags);
  1075. ret = dequeue_signal(tsk, mask, info);
  1076. spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
  1077. return ret;
  1078. }
  1079. extern void block_all_signals(int (*notifier)(void *priv), void *priv,
  1080. sigset_t *mask);
  1081. extern void unblock_all_signals(void);
  1082. extern void release_task(struct task_struct * p);
  1083. extern int send_sig_info(int, struct siginfo *, struct task_struct *);
  1084. extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
  1085. extern int force_sigsegv(int, struct task_struct *);
  1086. extern int force_sig_info(int, struct siginfo *, struct task_struct *);
  1087. extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
  1088. extern int kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
  1089. extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
  1090. extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
  1091. extern int kill_pgrp(struct pid *pid, int sig, int priv);
  1092. extern int kill_pid(struct pid *pid, int sig, int priv);
  1093. extern int __kill_pg_info(int sig, struct siginfo *info, pid_t pgrp);
  1094. extern int kill_pg_info(int, struct siginfo *, pid_t);
  1095. extern int kill_proc_info(int, struct siginfo *, pid_t);
  1096. extern void do_notify_parent(struct task_struct *, int);
  1097. extern void force_sig(int, struct task_struct *);
  1098. extern void force_sig_specific(int, struct task_struct *);
  1099. extern int send_sig(int, struct task_struct *, int);
  1100. extern void zap_other_threads(struct task_struct *p);
  1101. extern int kill_pg(pid_t, int, int);
  1102. extern int kill_proc(pid_t, int, int);
  1103. extern struct sigqueue *sigqueue_alloc(void);
  1104. extern void sigqueue_free(struct sigqueue *);
  1105. extern int send_sigqueue(int, struct sigqueue *, struct task_struct *);
  1106. extern int send_group_sigqueue(int, struct sigqueue *, struct task_struct *);
  1107. extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
  1108. extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
  1109. /* These can be the second arg to send_sig_info/send_group_sig_info. */
  1110. #define SEND_SIG_NOINFO ((struct siginfo *) 0)
  1111. #define SEND_SIG_PRIV ((struct siginfo *) 1)
  1112. #define SEND_SIG_FORCED ((struct siginfo *) 2)
  1113. static inline int is_si_special(const struct siginfo *info)
  1114. {
  1115. return info <= SEND_SIG_FORCED;
  1116. }
  1117. /* True if we are on the alternate signal stack. */
  1118. static inline int on_sig_stack(unsigned long sp)
  1119. {
  1120. return (sp - current->sas_ss_sp < current->sas_ss_size);
  1121. }
  1122. static inline int sas_ss_flags(unsigned long sp)
  1123. {
  1124. return (current->sas_ss_size == 0 ? SS_DISABLE
  1125. : on_sig_stack(sp) ? SS_ONSTACK : 0);
  1126. }
  1127. /*
  1128. * Routines for handling mm_structs
  1129. */
  1130. extern struct mm_struct * mm_alloc(void);
  1131. /* mmdrop drops the mm and the page tables */
  1132. extern void FASTCALL(__mmdrop(struct mm_struct *));
  1133. static inline void mmdrop(struct mm_struct * mm)
  1134. {
  1135. if (atomic_dec_and_test(&mm->mm_count))
  1136. __mmdrop(mm);
  1137. }
  1138. /* mmput gets rid of the mappings and all user-space */
  1139. extern void mmput(struct mm_struct *);
  1140. /* Grab a reference to a task's mm, if it is not already going away */
  1141. extern struct mm_struct *get_task_mm(struct task_struct *task);
  1142. /* Remove the current tasks stale references to the old mm_struct */
  1143. extern void mm_release(struct task_struct *, struct mm_struct *);
  1144. extern int copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
  1145. extern void flush_thread(void);
  1146. extern void exit_thread(void);
  1147. extern void exit_files(struct task_struct *);
  1148. extern void __cleanup_signal(struct signal_struct *);
  1149. extern void __cleanup_sighand(struct sighand_struct *);
  1150. extern void exit_itimers(struct signal_struct *);
  1151. extern NORET_TYPE void do_group_exit(int);
  1152. extern void daemonize(const char *, ...);
  1153. extern int allow_signal(int);
  1154. extern int disallow_signal(int);
  1155. extern struct task_struct *child_reaper;
  1156. extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
  1157. extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
  1158. struct task_struct *fork_idle(int);
  1159. extern void set_task_comm(struct task_struct *tsk, char *from);
  1160. extern void get_task_comm(char *to, struct task_struct *tsk);
  1161. #ifdef CONFIG_SMP
  1162. extern void wait_task_inactive(struct task_struct * p);
  1163. #else
  1164. #define wait_task_inactive(p) do { } while (0)
  1165. #endif
  1166. #define remove_parent(p) list_del_init(&(p)->sibling)
  1167. #define add_parent(p) list_add_tail(&(p)->sibling,&(p)->parent->children)
  1168. #define next_task(p) list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
  1169. #define for_each_process(p) \
  1170. for (p = &init_task ; (p = next_task(p)) != &init_task ; )
  1171. /*
  1172. * Careful: do_each_thread/while_each_thread is a double loop so
  1173. * 'break' will not work as expected - use goto instead.
  1174. */
  1175. #define do_each_thread(g, t) \
  1176. for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
  1177. #define while_each_thread(g, t) \
  1178. while ((t = next_thread(t)) != g)
  1179. /* de_thread depends on thread_group_leader not being a pid based check */
  1180. #define thread_group_leader(p) (p == p->group_leader)
  1181. /* Do to the insanities of de_thread it is possible for a process
  1182. * to have the pid of the thread group leader without actually being
  1183. * the thread group leader. For iteration through the pids in proc
  1184. * all we care about is that we have a task with the appropriate
  1185. * pid, we don't actually care if we have the right task.
  1186. */
  1187. static inline int has_group_leader_pid(struct task_struct *p)
  1188. {
  1189. return p->pid == p->tgid;
  1190. }
  1191. static inline struct task_struct *next_thread(const struct task_struct *p)
  1192. {
  1193. return list_entry(rcu_dereference(p->thread_group.next),
  1194. struct task_struct, thread_group);
  1195. }
  1196. static inline int thread_group_empty(struct task_struct *p)
  1197. {
  1198. return list_empty(&p->thread_group);
  1199. }
  1200. #define delay_group_leader(p) \
  1201. (thread_group_leader(p) && !thread_group_empty(p))
  1202. /*
  1203. * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
  1204. * subscriptions and synchronises with wait4(). Also used in procfs. Also
  1205. * pins the final release of task.io_context. Also protects ->cpuset.
  1206. *
  1207. * Nests both inside and outside of read_lock(&tasklist_lock).
  1208. * It must not be nested with write_lock_irq(&tasklist_lock),
  1209. * neither inside nor outside.
  1210. */
  1211. static inline void task_lock(struct task_struct *p)
  1212. {
  1213. spin_lock(&p->alloc_lock);
  1214. }
  1215. static inline void task_unlock(struct task_struct *p)
  1216. {
  1217. spin_unlock(&p->alloc_lock);
  1218. }
  1219. extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
  1220. unsigned long *flags);
  1221. static inline void unlock_task_sighand(struct task_struct *tsk,
  1222. unsigned long *flags)
  1223. {
  1224. spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
  1225. }
  1226. #ifndef __HAVE_THREAD_FUNCTIONS
  1227. #define task_thread_info(task) (task)->thread_info
  1228. #define task_stack_page(task) ((void*)((task)->thread_info))
  1229. static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
  1230. {
  1231. *task_thread_info(p) = *task_thread_info(org);
  1232. task_thread_info(p)->task = p;
  1233. }
  1234. static inline unsigned long *end_of_stack(struct task_struct *p)
  1235. {
  1236. return (unsigned long *)(p->thread_info + 1);
  1237. }
  1238. #endif
  1239. /* set thread flags in other task's structures
  1240. * - see asm/thread_info.h for TIF_xxxx flags available
  1241. */
  1242. static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
  1243. {
  1244. set_ti_thread_flag(task_thread_info(tsk), flag);
  1245. }
  1246. static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
  1247. {
  1248. clear_ti_thread_flag(task_thread_info(tsk), flag);
  1249. }
  1250. static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
  1251. {
  1252. return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
  1253. }
  1254. static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
  1255. {
  1256. return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
  1257. }
  1258. static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
  1259. {
  1260. return test_ti_thread_flag(task_thread_info(tsk), flag);
  1261. }
  1262. static inline void set_tsk_need_resched(struct task_struct *tsk)
  1263. {
  1264. set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
  1265. }
  1266. static inline void clear_tsk_need_resched(struct task_struct *tsk)
  1267. {
  1268. clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
  1269. }
  1270. static inline int signal_pending(struct task_struct *p)
  1271. {
  1272. return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
  1273. }
  1274. static inline int need_resched(void)
  1275. {
  1276. return unlikely(test_thread_flag(TIF_NEED_RESCHED));
  1277. }
  1278. /*
  1279. * cond_resched() and cond_resched_lock(): latency reduction via
  1280. * explicit rescheduling in places that are safe. The return
  1281. * value indicates whether a reschedule was done in fact.
  1282. * cond_resched_lock() will drop the spinlock before scheduling,
  1283. * cond_resched_softirq() will enable bhs before scheduling.
  1284. */
  1285. extern int cond_resched(void);
  1286. extern int cond_resched_lock(spinlock_t * lock);
  1287. extern int cond_resched_softirq(void);
  1288. /*
  1289. * Does a critical section need to be broken due to another
  1290. * task waiting?:
  1291. */
  1292. #if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
  1293. # define need_lockbreak(lock) ((lock)->break_lock)
  1294. #else
  1295. # define need_lockbreak(lock) 0
  1296. #endif
  1297. /*
  1298. * Does a critical section need to be broken due to another
  1299. * task waiting or preemption being signalled:
  1300. */
  1301. static inline int lock_need_resched(spinlock_t *lock)
  1302. {
  1303. if (need_lockbreak(lock) || need_resched())
  1304. return 1;
  1305. return 0;
  1306. }
  1307. /* Reevaluate whether the task has signals pending delivery.
  1308. This is required every time the blocked sigset_t changes.
  1309. callers must hold sighand->siglock. */
  1310. extern FASTCALL(void recalc_sigpending_tsk(struct task_struct *t));
  1311. extern void recalc_sigpending(void);
  1312. extern void signal_wake_up(struct task_struct *t, int resume_stopped);
  1313. /*
  1314. * Wrappers for p->thread_info->cpu access. No-op on UP.
  1315. */
  1316. #ifdef CONFIG_SMP
  1317. static inline unsigned int task_cpu(const struct task_struct *p)
  1318. {
  1319. return task_thread_info(p)->cpu;
  1320. }
  1321. static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
  1322. {
  1323. task_thread_info(p)->cpu = cpu;
  1324. }
  1325. #else
  1326. static inline unsigned int task_cpu(const struct task_struct *p)
  1327. {
  1328. return 0;
  1329. }
  1330. static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
  1331. {
  1332. }
  1333. #endif /* CONFIG_SMP */
  1334. #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
  1335. extern void arch_pick_mmap_layout(struct mm_struct *mm);
  1336. #else
  1337. static inline void arch_pick_mmap_layout(struct mm_struct *mm)
  1338. {
  1339. mm->mmap_base = TASK_UNMAPPED_BASE;
  1340. mm->get_unmapped_area = arch_get_unmapped_area;
  1341. mm->unmap_area = arch_unmap_area;
  1342. }
  1343. #endif
  1344. extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
  1345. extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
  1346. #include <linux/sysdev.h>
  1347. extern int sched_mc_power_savings, sched_smt_power_savings;
  1348. extern struct sysdev_attribute attr_sched_mc_power_savings, attr_sched_smt_power_savings;
  1349. extern int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls);
  1350. extern void normalize_rt_tasks(void);
  1351. #ifdef CONFIG_PM
  1352. /*
  1353. * Check if a process has been frozen
  1354. */
  1355. static inline int frozen(struct task_struct *p)
  1356. {
  1357. return p->flags & PF_FROZEN;
  1358. }
  1359. /*
  1360. * Check if there is a request to freeze a process
  1361. */
  1362. static inline int freezing(struct task_struct *p)
  1363. {
  1364. return p->flags & PF_FREEZE;
  1365. }
  1366. /*
  1367. * Request that a process be frozen
  1368. * FIXME: SMP problem. We may not modify other process' flags!
  1369. */
  1370. static inline void freeze(struct task_struct *p)
  1371. {
  1372. p->flags |= PF_FREEZE;
  1373. }
  1374. /*
  1375. * Sometimes we may need to cancel the previous 'freeze' request
  1376. */
  1377. static inline void do_not_freeze(struct task_struct *p)
  1378. {
  1379. p->flags &= ~PF_FREEZE;
  1380. }
  1381. /*
  1382. * Wake up a frozen process
  1383. */
  1384. static inline int thaw_process(struct task_struct *p)
  1385. {
  1386. if (frozen(p)) {
  1387. p->flags &= ~PF_FROZEN;
  1388. wake_up_process(p);
  1389. return 1;
  1390. }
  1391. return 0;
  1392. }
  1393. /*
  1394. * freezing is complete, mark process as frozen
  1395. */
  1396. static inline void frozen_process(struct task_struct *p)
  1397. {
  1398. p->flags = (p->flags & ~PF_FREEZE) | PF_FROZEN;
  1399. }
  1400. extern void refrigerator(void);
  1401. extern int freeze_processes(void);
  1402. extern void thaw_processes(void);
  1403. static inline int try_to_freeze(void)
  1404. {
  1405. if (freezing(current)) {
  1406. refrigerator();
  1407. return 1;
  1408. } else
  1409. return 0;
  1410. }
  1411. #else
  1412. static inline int frozen(struct task_struct *p) { return 0; }
  1413. static inline int freezing(struct task_struct *p) { return 0; }
  1414. static inline void freeze(struct task_struct *p) { BUG(); }
  1415. static inline int thaw_process(struct task_struct *p) { return 1; }
  1416. static inline void frozen_process(struct task_struct *p) { BUG(); }
  1417. static inline void refrigerator(void) {}
  1418. static inline int freeze_processes(void) { BUG(); return 0; }
  1419. static inline void thaw_processes(void) {}
  1420. static inline int try_to_freeze(void) { return 0; }
  1421. #endif /* CONFIG_PM */
  1422. #endif /* __KERNEL__ */
  1423. #endif