sched.h 42 KB

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