linux/include/linux/sched.h
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   1#ifndef _LINUX_SCHED_H
   2#define _LINUX_SCHED_H
   3
   4#include <linux/auxvec.h>       /* For AT_VECTOR_SIZE */
   5
   6/*
   7 * cloning flags:
   8 */
   9#define CSIGNAL         0x000000ff      /* signal mask to be sent at exit */
  10#define CLONE_VM        0x00000100      /* set if VM shared between processes */
  11#define CLONE_FS        0x00000200      /* set if fs info shared between processes */
  12#define CLONE_FILES     0x00000400      /* set if open files shared between processes */
  13#define CLONE_SIGHAND   0x00000800      /* set if signal handlers and blocked signals shared */
  14#define CLONE_PTRACE    0x00002000      /* set if we want to let tracing continue on the child too */
  15#define CLONE_VFORK     0x00004000      /* set if the parent wants the child to wake it up on mm_release */
  16#define CLONE_PARENT    0x00008000      /* set if we want to have the same parent as the cloner */
  17#define CLONE_THREAD    0x00010000      /* Same thread group? */
  18#define CLONE_NEWNS     0x00020000      /* New namespace group? */
  19#define CLONE_SYSVSEM   0x00040000      /* share system V SEM_UNDO semantics */
  20#define CLONE_SETTLS    0x00080000      /* create a new TLS for the child */
  21#define CLONE_PARENT_SETTID     0x00100000      /* set the TID in the parent */
  22#define CLONE_CHILD_CLEARTID    0x00200000      /* clear the TID in the child */
  23#define CLONE_DETACHED          0x00400000      /* Unused, ignored */
  24#define CLONE_UNTRACED          0x00800000      /* set if the tracing process can't force CLONE_PTRACE on this clone */
  25#define CLONE_CHILD_SETTID      0x01000000      /* set the TID in the child */
  26#define CLONE_STOPPED           0x02000000      /* Start in stopped state */
  27
  28/*
  29 * Scheduling policies
  30 */
  31#define SCHED_NORMAL            0
  32#define SCHED_FIFO              1
  33#define SCHED_RR                2
  34#define SCHED_BATCH             3
  35
  36#ifdef __KERNEL__
  37
  38struct sched_param {
  39        int sched_priority;
  40};
  41
  42#include <asm/param.h>  /* for HZ */
  43
  44#include <linux/capability.h>
  45#include <linux/threads.h>
  46#include <linux/kernel.h>
  47#include <linux/types.h>
  48#include <linux/timex.h>
  49#include <linux/jiffies.h>
  50#include <linux/rbtree.h>
  51#include <linux/thread_info.h>
  52#include <linux/cpumask.h>
  53#include <linux/errno.h>
  54#include <linux/nodemask.h>
  55
  56#include <asm/system.h>
  57#include <asm/semaphore.h>
  58#include <asm/page.h>
  59#include <asm/ptrace.h>
  60#include <asm/mmu.h>
  61#include <asm/cputime.h>
  62
  63#include <linux/smp.h>
  64#include <linux/sem.h>
  65#include <linux/signal.h>
  66#include <linux/securebits.h>
  67#include <linux/fs_struct.h>
  68#include <linux/compiler.h>
  69#include <linux/completion.h>
  70#include <linux/pid.h>
  71#include <linux/percpu.h>
  72#include <linux/topology.h>
  73#include <linux/seccomp.h>
  74#include <linux/rcupdate.h>
  75#include <linux/futex.h>
  76#include <linux/rtmutex.h>
  77
  78#include <linux/time.h>
  79#include <linux/param.h>
  80#include <linux/resource.h>
  81#include <linux/timer.h>
  82#include <linux/hrtimer.h>
  83
  84#include <asm/processor.h>
  85
  86struct exec_domain;
  87struct futex_pi_state;
  88
  89/*
  90 * List of flags we want to share for kernel threads,
  91 * if only because they are not used by them anyway.
  92 */
  93#define CLONE_KERNEL    (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
  94
  95/*
  96 * These are the constant used to fake the fixed-point load-average
  97 * counting. Some notes:
  98 *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
  99 *    a load-average precision of 10 bits integer + 11 bits fractional
 100 *  - if you want to count load-averages more often, you need more
 101 *    precision, or rounding will get you. With 2-second counting freq,
 102 *    the EXP_n values would be 1981, 2034 and 2043 if still using only
 103 *    11 bit fractions.
 104 */
 105extern unsigned long avenrun[];         /* Load averages */
 106
 107#define FSHIFT          11              /* nr of bits of precision */
 108#define FIXED_1         (1<<FSHIFT)     /* 1.0 as fixed-point */
 109#define LOAD_FREQ       (5*HZ)          /* 5 sec intervals */
 110#define EXP_1           1884            /* 1/exp(5sec/1min) as fixed-point */
 111#define EXP_5           2014            /* 1/exp(5sec/5min) */
 112#define EXP_15          2037            /* 1/exp(5sec/15min) */
 113
 114#define CALC_LOAD(load,exp,n) \
 115        load *= exp; \
 116        load += n*(FIXED_1-exp); \
 117        load >>= FSHIFT;
 118
 119extern unsigned long total_forks;
 120extern int nr_threads;
 121extern int last_pid;
 122DECLARE_PER_CPU(unsigned long, process_counts);
 123extern int nr_processes(void);
 124extern unsigned long nr_running(void);
 125extern unsigned long nr_uninterruptible(void);
 126extern unsigned long nr_active(void);
 127extern unsigned long nr_iowait(void);
 128extern unsigned long weighted_cpuload(const int cpu);
 129
 130
 131/*
 132 * Task state bitmask. NOTE! These bits are also
 133 * encoded in fs/proc/array.c: get_task_state().
 134 *
 135 * We have two separate sets of flags: task->state
 136 * is about runnability, while task->exit_state are
 137 * about the task exiting. Confusing, but this way
 138 * modifying one set can't modify the other one by
 139 * mistake.
 140 */
 141#define TASK_RUNNING            0
 142#define TASK_INTERRUPTIBLE      1
 143#define TASK_UNINTERRUPTIBLE    2
 144#define TASK_STOPPED            4
 145#define TASK_TRACED             8
 146/* in tsk->exit_state */
 147#define EXIT_ZOMBIE             16
 148#define EXIT_DEAD               32
 149/* in tsk->state again */
 150#define TASK_NONINTERACTIVE     64
 151
 152#define __set_task_state(tsk, state_value)              \
 153        do { (tsk)->state = (state_value); } while (0)
 154#define set_task_state(tsk, state_value)                \
 155        set_mb((tsk)->state, (state_value))
 156
 157/*
 158 * set_current_state() includes a barrier so that the write of current->state
 159 * is correctly serialised wrt the caller's subsequent test of whether to
 160 * actually sleep:
 161 *
 162 *      set_current_state(TASK_UNINTERRUPTIBLE);
 163 *      if (do_i_need_to_sleep())
 164 *              schedule();
 165 *
 166 * If the caller does not need such serialisation then use __set_current_state()
 167 */
 168#define __set_current_state(state_value)                        \
 169        do { current->state = (state_value); } while (0)
 170#define set_current_state(state_value)          \
 171        set_mb(current->state, (state_value))
 172
 173/* Task command name length */
 174#define TASK_COMM_LEN 16
 175
 176#include <linux/spinlock.h>
 177
 178/*
 179 * This serializes "schedule()" and also protects
 180 * the run-queue from deletions/modifications (but
 181 * _adding_ to the beginning of the run-queue has
 182 * a separate lock).
 183 */
 184extern rwlock_t tasklist_lock;
 185extern spinlock_t mmlist_lock;
 186
 187struct task_struct;
 188
 189extern void sched_init(void);
 190extern void sched_init_smp(void);
 191extern void init_idle(struct task_struct *idle, int cpu);
 192
 193extern cpumask_t nohz_cpu_mask;
 194
 195extern void show_state(void);
 196extern void show_regs(struct pt_regs *);
 197
 198/*
 199 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
 200 * task), SP is the stack pointer of the first frame that should be shown in the back
 201 * trace (or NULL if the entire call-chain of the task should be shown).
 202 */
 203extern void show_stack(struct task_struct *task, unsigned long *sp);
 204
 205void io_schedule(void);
 206long io_schedule_timeout(long timeout);
 207
 208extern void cpu_init (void);
 209extern void trap_init(void);
 210extern void update_process_times(int user);
 211extern void scheduler_tick(void);
 212
 213#ifdef CONFIG_DETECT_SOFTLOCKUP
 214extern void softlockup_tick(void);
 215extern void spawn_softlockup_task(void);
 216extern void touch_softlockup_watchdog(void);
 217#else
 218static inline void softlockup_tick(void)
 219{
 220}
 221static inline void spawn_softlockup_task(void)
 222{
 223}
 224static inline void touch_softlockup_watchdog(void)
 225{
 226}
 227#endif
 228
 229
 230/* Attach to any functions which should be ignored in wchan output. */
 231#define __sched         __attribute__((__section__(".sched.text")))
 232/* Is this address in the __sched functions? */
 233extern int in_sched_functions(unsigned long addr);
 234
 235#define MAX_SCHEDULE_TIMEOUT    LONG_MAX
 236extern signed long FASTCALL(schedule_timeout(signed long timeout));
 237extern signed long schedule_timeout_interruptible(signed long timeout);
 238extern signed long schedule_timeout_uninterruptible(signed long timeout);
 239asmlinkage void schedule(void);
 240
 241struct namespace;
 242
 243/* Maximum number of active map areas.. This is a random (large) number */
 244#define DEFAULT_MAX_MAP_COUNT   65536
 245
 246extern int sysctl_max_map_count;
 247
 248#include <linux/aio.h>
 249
 250extern unsigned long
 251arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
 252                       unsigned long, unsigned long);
 253extern unsigned long
 254arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
 255                          unsigned long len, unsigned long pgoff,
 256                          unsigned long flags);
 257extern void arch_unmap_area(struct mm_struct *, unsigned long);
 258extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
 259
 260#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
 261/*
 262 * The mm counters are not protected by its page_table_lock,
 263 * so must be incremented atomically.
 264 */
 265#define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
 266#define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
 267#define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
 268#define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
 269#define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
 270typedef atomic_long_t mm_counter_t;
 271
 272#else  /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
 273/*
 274 * The mm counters are protected by its page_table_lock,
 275 * so can be incremented directly.
 276 */
 277#define set_mm_counter(mm, member, value) (mm)->_##member = (value)
 278#define get_mm_counter(mm, member) ((mm)->_##member)
 279#define add_mm_counter(mm, member, value) (mm)->_##member += (value)
 280#define inc_mm_counter(mm, member) (mm)->_##member++
 281#define dec_mm_counter(mm, member) (mm)->_##member--
 282typedef unsigned long mm_counter_t;
 283
 284#endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
 285
 286#define get_mm_rss(mm)                                  \
 287        (get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
 288#define update_hiwater_rss(mm)  do {                    \
 289        unsigned long _rss = get_mm_rss(mm);            \
 290        if ((mm)->hiwater_rss < _rss)                   \
 291                (mm)->hiwater_rss = _rss;               \
 292} while (0)
 293#define update_hiwater_vm(mm)   do {                    \
 294        if ((mm)->hiwater_vm < (mm)->total_vm)          \
 295                (mm)->hiwater_vm = (mm)->total_vm;      \
 296} while (0)
 297
 298struct mm_struct {
 299        struct vm_area_struct * mmap;           /* list of VMAs */
 300        struct rb_root mm_rb;
 301        struct vm_area_struct * mmap_cache;     /* last find_vma result */
 302        unsigned long (*get_unmapped_area) (struct file *filp,
 303                                unsigned long addr, unsigned long len,
 304                                unsigned long pgoff, unsigned long flags);
 305        void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
 306        unsigned long mmap_base;                /* base of mmap area */
 307        unsigned long task_size;                /* size of task vm space */
 308        unsigned long cached_hole_size;         /* if non-zero, the largest hole below free_area_cache */
 309        unsigned long free_area_cache;          /* first hole of size cached_hole_size or larger */
 310        pgd_t * pgd;
 311        atomic_t mm_users;                      /* How many users with user space? */
 312        atomic_t mm_count;                      /* How many references to "struct mm_struct" (users count as 1) */
 313        int map_count;                          /* number of VMAs */
 314        struct rw_semaphore mmap_sem;
 315        spinlock_t page_table_lock;             /* Protects page tables and some counters */
 316
 317        struct list_head mmlist;                /* List of maybe swapped mm's.  These are globally strung
 318                                                 * together off init_mm.mmlist, and are protected
 319                                                 * by mmlist_lock
 320                                                 */
 321
 322        /* Special counters, in some configurations protected by the
 323         * page_table_lock, in other configurations by being atomic.
 324         */
 325        mm_counter_t _file_rss;
 326        mm_counter_t _anon_rss;
 327
 328        unsigned long hiwater_rss;      /* High-watermark of RSS usage */
 329        unsigned long hiwater_vm;       /* High-water virtual memory usage */
 330
 331        unsigned long total_vm, locked_vm, shared_vm, exec_vm;
 332        unsigned long stack_vm, reserved_vm, def_flags, nr_ptes;
 333        unsigned long start_code, end_code, start_data, end_data;
 334        unsigned long start_brk, brk, start_stack;
 335        unsigned long arg_start, arg_end, env_start, env_end;
 336
 337        unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
 338
 339        unsigned dumpable:2;
 340        cpumask_t cpu_vm_mask;
 341
 342        /* Architecture-specific MM context */
 343        mm_context_t context;
 344
 345        /* Token based thrashing protection. */
 346        unsigned long swap_token_time;
 347        char recent_pagein;
 348
 349        /* coredumping support */
 350        int core_waiters;
 351        struct completion *core_startup_done, core_done;
 352
 353        /* aio bits */
 354        rwlock_t                ioctx_list_lock;
 355        struct kioctx           *ioctx_list;
 356};
 357
 358struct sighand_struct {
 359        atomic_t                count;
 360        struct k_sigaction      action[_NSIG];
 361        spinlock_t              siglock;
 362};
 363
 364struct pacct_struct {
 365        int                     ac_flag;
 366        long                    ac_exitcode;
 367        unsigned long           ac_mem;
 368        cputime_t               ac_utime, ac_stime;
 369        unsigned long           ac_minflt, ac_majflt;
 370};
 371
 372/*
 373 * NOTE! "signal_struct" does not have it's own
 374 * locking, because a shared signal_struct always
 375 * implies a shared sighand_struct, so locking
 376 * sighand_struct is always a proper superset of
 377 * the locking of signal_struct.
 378 */
 379struct signal_struct {
 380        atomic_t                count;
 381        atomic_t                live;
 382
 383        wait_queue_head_t       wait_chldexit;  /* for wait4() */
 384
 385        /* current thread group signal load-balancing target: */
 386        struct task_struct      *curr_target;
 387
 388        /* shared signal handling: */
 389        struct sigpending       shared_pending;
 390
 391        /* thread group exit support */
 392        int                     group_exit_code;
 393        /* overloaded:
 394         * - notify group_exit_task when ->count is equal to notify_count
 395         * - everyone except group_exit_task is stopped during signal delivery
 396         *   of fatal signals, group_exit_task processes the signal.
 397         */
 398        struct task_struct      *group_exit_task;
 399        int                     notify_count;
 400
 401        /* thread group stop support, overloads group_exit_code too */
 402        int                     group_stop_count;
 403        unsigned int            flags; /* see SIGNAL_* flags below */
 404
 405        /* POSIX.1b Interval Timers */
 406        struct list_head posix_timers;
 407
 408        /* ITIMER_REAL timer for the process */
 409        struct hrtimer real_timer;
 410        struct task_struct *tsk;
 411        ktime_t it_real_incr;
 412
 413        /* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
 414        cputime_t it_prof_expires, it_virt_expires;
 415        cputime_t it_prof_incr, it_virt_incr;
 416
 417        /* job control IDs */
 418        pid_t pgrp;
 419        pid_t tty_old_pgrp;
 420        pid_t session;
 421        /* boolean value for session group leader */
 422        int leader;
 423
 424        struct tty_struct *tty; /* NULL if no tty */
 425
 426        /*
 427         * Cumulative resource counters for dead threads in the group,
 428         * and for reaped dead child processes forked by this group.
 429         * Live threads maintain their own counters and add to these
 430         * in __exit_signal, except for the group leader.
 431         */
 432        cputime_t utime, stime, cutime, cstime;
 433        unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
 434        unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
 435
 436        /*
 437         * Cumulative ns of scheduled CPU time for dead threads in the
 438         * group, not including a zombie group leader.  (This only differs
 439         * from jiffies_to_ns(utime + stime) if sched_clock uses something
 440         * other than jiffies.)
 441         */
 442        unsigned long long sched_time;
 443
 444        /*
 445         * We don't bother to synchronize most readers of this at all,
 446         * because there is no reader checking a limit that actually needs
 447         * to get both rlim_cur and rlim_max atomically, and either one
 448         * alone is a single word that can safely be read normally.
 449         * getrlimit/setrlimit use task_lock(current->group_leader) to
 450         * protect this instead of the siglock, because they really
 451         * have no need to disable irqs.
 452         */
 453        struct rlimit rlim[RLIM_NLIMITS];
 454
 455        struct list_head cpu_timers[3];
 456
 457        /* keep the process-shared keyrings here so that they do the right
 458         * thing in threads created with CLONE_THREAD */
 459#ifdef CONFIG_KEYS
 460        struct key *session_keyring;    /* keyring inherited over fork */
 461        struct key *process_keyring;    /* keyring private to this process */
 462#endif
 463#ifdef CONFIG_BSD_PROCESS_ACCT
 464        struct pacct_struct pacct;      /* per-process accounting information */
 465#endif
 466#ifdef CONFIG_TASKSTATS
 467        spinlock_t stats_lock;
 468        struct taskstats *stats;
 469#endif
 470};
 471
 472/* Context switch must be unlocked if interrupts are to be enabled */
 473#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
 474# define __ARCH_WANT_UNLOCKED_CTXSW
 475#endif
 476
 477/*
 478 * Bits in flags field of signal_struct.
 479 */
 480#define SIGNAL_STOP_STOPPED     0x00000001 /* job control stop in effect */
 481#define SIGNAL_STOP_DEQUEUED    0x00000002 /* stop signal dequeued */
 482#define SIGNAL_STOP_CONTINUED   0x00000004 /* SIGCONT since WCONTINUED reap */
 483#define SIGNAL_GROUP_EXIT       0x00000008 /* group exit in progress */
 484
 485
 486/*
 487 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
 488 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
 489 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
 490 * values are inverted: lower p->prio value means higher priority.
 491 *
 492 * The MAX_USER_RT_PRIO value allows the actual maximum
 493 * RT priority to be separate from the value exported to
 494 * user-space.  This allows kernel threads to set their
 495 * priority to a value higher than any user task. Note:
 496 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
 497 */
 498
 499#define MAX_USER_RT_PRIO        100
 500#define MAX_RT_PRIO             MAX_USER_RT_PRIO
 501
 502#define MAX_PRIO                (MAX_RT_PRIO + 40)
 503
 504#define rt_prio(prio)           unlikely((prio) < MAX_RT_PRIO)
 505#define rt_task(p)              rt_prio((p)->prio)
 506#define batch_task(p)           (unlikely((p)->policy == SCHED_BATCH))
 507#define has_rt_policy(p) \
 508        unlikely((p)->policy != SCHED_NORMAL && (p)->policy != SCHED_BATCH)
 509
 510/*
 511 * Some day this will be a full-fledged user tracking system..
 512 */
 513struct user_struct {
 514        atomic_t __count;       /* reference count */
 515        atomic_t processes;     /* How many processes does this user have? */
 516        atomic_t files;         /* How many open files does this user have? */
 517        atomic_t sigpending;    /* How many pending signals does this user have? */
 518#ifdef CONFIG_INOTIFY_USER
 519        atomic_t inotify_watches; /* How many inotify watches does this user have? */
 520        atomic_t inotify_devs;  /* How many inotify devs does this user have opened? */
 521#endif
 522        /* protected by mq_lock */
 523        unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
 524        unsigned long locked_shm; /* How many pages of mlocked shm ? */
 525
 526#ifdef CONFIG_KEYS
 527        struct key *uid_keyring;        /* UID specific keyring */
 528        struct key *session_keyring;    /* UID's default session keyring */
 529#endif
 530
 531        /* Hash table maintenance information */
 532        struct list_head uidhash_list;
 533        uid_t uid;
 534};
 535
 536extern struct user_struct *find_user(uid_t);
 537
 538extern struct user_struct root_user;
 539#define INIT_USER (&root_user)
 540
 541struct backing_dev_info;
 542struct reclaim_state;
 543
 544#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
 545struct sched_info {
 546        /* cumulative counters */
 547        unsigned long   cpu_time,       /* time spent on the cpu */
 548                        run_delay,      /* time spent waiting on a runqueue */
 549                        pcnt;           /* # of timeslices run on this cpu */
 550
 551        /* timestamps */
 552        unsigned long   last_arrival,   /* when we last ran on a cpu */
 553                        last_queued;    /* when we were last queued to run */
 554};
 555#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
 556
 557#ifdef CONFIG_SCHEDSTATS
 558extern struct file_operations proc_schedstat_operations;
 559#endif /* CONFIG_SCHEDSTATS */
 560
 561#ifdef CONFIG_TASK_DELAY_ACCT
 562struct task_delay_info {
 563        spinlock_t      lock;
 564        unsigned int    flags;  /* Private per-task flags */
 565
 566        /* For each stat XXX, add following, aligned appropriately
 567         *
 568         * struct timespec XXX_start, XXX_end;
 569         * u64 XXX_delay;
 570         * u32 XXX_count;
 571         *
 572         * Atomicity of updates to XXX_delay, XXX_count protected by
 573         * single lock above (split into XXX_lock if contention is an issue).
 574         */
 575
 576        /*
 577         * XXX_count is incremented on every XXX operation, the delay
 578         * associated with the operation is added to XXX_delay.
 579         * XXX_delay contains the accumulated delay time in nanoseconds.
 580         */
 581        struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */
 582        u64 blkio_delay;        /* wait for sync block io completion */
 583        u64 swapin_delay;       /* wait for swapin block io completion */
 584        u32 blkio_count;        /* total count of the number of sync block */
 585                                /* io operations performed */
 586        u32 swapin_count;       /* total count of the number of swapin block */
 587                                /* io operations performed */
 588};
 589#endif  /* CONFIG_TASK_DELAY_ACCT */
 590
 591static inline int sched_info_on(void)
 592{
 593#ifdef CONFIG_SCHEDSTATS
 594        return 1;
 595#elif defined(CONFIG_TASK_DELAY_ACCT)
 596        extern int delayacct_on;
 597        return delayacct_on;
 598#else
 599        return 0;
 600#endif
 601}
 602
 603enum idle_type
 604{
 605        SCHED_IDLE,
 606        NOT_IDLE,
 607        NEWLY_IDLE,
 608        MAX_IDLE_TYPES
 609};
 610
 611/*
 612 * sched-domains (multiprocessor balancing) declarations:
 613 */
 614#define SCHED_LOAD_SCALE        128UL   /* increase resolution of load */
 615
 616#ifdef CONFIG_SMP
 617#define SD_LOAD_BALANCE         1       /* Do load balancing on this domain. */
 618#define SD_BALANCE_NEWIDLE      2       /* Balance when about to become idle */
 619#define SD_BALANCE_EXEC         4       /* Balance on exec */
 620#define SD_BALANCE_FORK         8       /* Balance on fork, clone */
 621#define SD_WAKE_IDLE            16      /* Wake to idle CPU on task wakeup */
 622#define SD_WAKE_AFFINE          32      /* Wake task to waking CPU */
 623#define SD_WAKE_BALANCE         64      /* Perform balancing at task wakeup */
 624#define SD_SHARE_CPUPOWER       128     /* Domain members share cpu power */
 625#define SD_POWERSAVINGS_BALANCE 256     /* Balance for power savings */
 626
 627#define BALANCE_FOR_POWER       ((sched_mc_power_savings || sched_smt_power_savings) \
 628                                 ? SD_POWERSAVINGS_BALANCE : 0)
 629
 630
 631struct sched_group {
 632        struct sched_group *next;       /* Must be a circular list */
 633        cpumask_t cpumask;
 634
 635        /*
 636         * CPU power of this group, SCHED_LOAD_SCALE being max power for a
 637         * single CPU. This is read only (except for setup, hotplug CPU).
 638         */
 639        unsigned long cpu_power;
 640};
 641
 642struct sched_domain {
 643        /* These fields must be setup */
 644        struct sched_domain *parent;    /* top domain must be null terminated */
 645        struct sched_group *groups;     /* the balancing groups of the domain */
 646        cpumask_t span;                 /* span of all CPUs in this domain */
 647        unsigned long min_interval;     /* Minimum balance interval ms */
 648        unsigned long max_interval;     /* Maximum balance interval ms */
 649        unsigned int busy_factor;       /* less balancing by factor if busy */
 650        unsigned int imbalance_pct;     /* No balance until over watermark */
 651        unsigned long long cache_hot_time; /* Task considered cache hot (ns) */
 652        unsigned int cache_nice_tries;  /* Leave cache hot tasks for # tries */
 653        unsigned int per_cpu_gain;      /* CPU % gained by adding domain cpus */
 654        unsigned int busy_idx;
 655        unsigned int idle_idx;
 656        unsigned int newidle_idx;
 657        unsigned int wake_idx;
 658        unsigned int forkexec_idx;
 659        int flags;                      /* See SD_* */
 660
 661        /* Runtime fields. */
 662        unsigned long last_balance;     /* init to jiffies. units in jiffies */
 663        unsigned int balance_interval;  /* initialise to 1. units in ms. */
 664        unsigned int nr_balance_failed; /* initialise to 0 */
 665
 666#ifdef CONFIG_SCHEDSTATS
 667        /* load_balance() stats */
 668        unsigned long lb_cnt[MAX_IDLE_TYPES];
 669        unsigned long lb_failed[MAX_IDLE_TYPES];
 670        unsigned long lb_balanced[MAX_IDLE_TYPES];
 671        unsigned long lb_imbalance[MAX_IDLE_TYPES];
 672        unsigned long lb_gained[MAX_IDLE_TYPES];
 673        unsigned long lb_hot_gained[MAX_IDLE_TYPES];
 674        unsigned long lb_nobusyg[MAX_IDLE_TYPES];
 675        unsigned long lb_nobusyq[MAX_IDLE_TYPES];
 676
 677        /* Active load balancing */
 678        unsigned long alb_cnt;
 679        unsigned long alb_failed;
 680        unsigned long alb_pushed;
 681
 682        /* SD_BALANCE_EXEC stats */
 683        unsigned long sbe_cnt;
 684        unsigned long sbe_balanced;
 685        unsigned long sbe_pushed;
 686
 687        /* SD_BALANCE_FORK stats */
 688        unsigned long sbf_cnt;
 689        unsigned long sbf_balanced;
 690        unsigned long sbf_pushed;
 691
 692        /* try_to_wake_up() stats */
 693        unsigned long ttwu_wake_remote;
 694        unsigned long ttwu_move_affine;
 695        unsigned long ttwu_move_balance;
 696#endif
 697};
 698
 699extern int partition_sched_domains(cpumask_t *partition1,
 700                                    cpumask_t *partition2);
 701
 702/*
 703 * Maximum cache size the migration-costs auto-tuning code will
 704 * search from:
 705 */
 706extern unsigned int max_cache_size;
 707
 708#endif  /* CONFIG_SMP */
 709
 710
 711struct io_context;                      /* See blkdev.h */
 712void exit_io_context(void);
 713struct cpuset;
 714
 715#define NGROUPS_SMALL           32
 716#define NGROUPS_PER_BLOCK       ((int)(PAGE_SIZE / sizeof(gid_t)))
 717struct group_info {
 718        int ngroups;
 719        atomic_t usage;
 720        gid_t small_block[NGROUPS_SMALL];
 721        int nblocks;
 722        gid_t *blocks[0];
 723};
 724
 725/*
 726 * get_group_info() must be called with the owning task locked (via task_lock())
 727 * when task != current.  The reason being that the vast majority of callers are
 728 * looking at current->group_info, which can not be changed except by the
 729 * current task.  Changing current->group_info requires the task lock, too.
 730 */
 731#define get_group_info(group_info) do { \
 732        atomic_inc(&(group_info)->usage); \
 733} while (0)
 734
 735#define put_group_info(group_info) do { \
 736        if (atomic_dec_and_test(&(group_info)->usage)) \
 737                groups_free(group_info); \
 738} while (0)
 739
 740extern struct group_info *groups_alloc(int gidsetsize);
 741extern void groups_free(struct group_info *group_info);
 742extern int set_current_groups(struct group_info *group_info);
 743extern int groups_search(struct group_info *group_info, gid_t grp);
 744/* access the groups "array" with this macro */
 745#define GROUP_AT(gi, i) \
 746    ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
 747
 748#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
 749extern void prefetch_stack(struct task_struct *t);
 750#else
 751static inline void prefetch_stack(struct task_struct *t) { }
 752#endif
 753
 754struct audit_context;           /* See audit.c */
 755struct mempolicy;
 756struct pipe_inode_info;
 757
 758enum sleep_type {
 759        SLEEP_NORMAL,
 760        SLEEP_NONINTERACTIVE,
 761        SLEEP_INTERACTIVE,
 762        SLEEP_INTERRUPTED,
 763};
 764
 765struct prio_array;
 766
 767struct task_struct {
 768        volatile long state;    /* -1 unrunnable, 0 runnable, >0 stopped */
 769        struct thread_info *thread_info;
 770        atomic_t usage;
 771        unsigned long flags;    /* per process flags, defined below */
 772        unsigned long ptrace;
 773
 774        int lock_depth;         /* BKL lock depth */
 775
 776#ifdef CONFIG_SMP
 777#ifdef __ARCH_WANT_UNLOCKED_CTXSW
 778        int oncpu;
 779#endif
 780#endif
 781        int load_weight;        /* for niceness load balancing purposes */
 782        int prio, static_prio, normal_prio;
 783        struct list_head run_list;
 784        struct prio_array *array;
 785
 786        unsigned short ioprio;
 787        unsigned int btrace_seq;
 788
 789        unsigned long sleep_avg;
 790        unsigned long long timestamp, last_ran;
 791        unsigned long long sched_time; /* sched_clock time spent running */
 792        enum sleep_type sleep_type;
 793
 794        unsigned long policy;
 795        cpumask_t cpus_allowed;
 796        unsigned int time_slice, first_time_slice;
 797
 798#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
 799        struct sched_info sched_info;
 800#endif
 801
 802        struct list_head tasks;
 803        /*
 804         * ptrace_list/ptrace_children forms the list of my children
 805         * that were stolen by a ptracer.
 806         */
 807        struct list_head ptrace_children;
 808        struct list_head ptrace_list;
 809
 810        struct mm_struct *mm, *active_mm;
 811
 812/* task state */
 813        struct linux_binfmt *binfmt;
 814        long exit_state;
 815        int exit_code, exit_signal;
 816        int pdeath_signal;  /*  The signal sent when the parent dies  */
 817        /* ??? */
 818        unsigned long personality;
 819        unsigned did_exec:1;
 820        pid_t pid;
 821        pid_t tgid;
 822        /* 
 823         * pointers to (original) parent process, youngest child, younger sibling,
 824         * older sibling, respectively.  (p->father can be replaced with 
 825         * p->parent->pid)
 826         */
 827        struct task_struct *real_parent; /* real parent process (when being debugged) */
 828        struct task_struct *parent;     /* parent process */
 829        /*
 830         * children/sibling forms the list of my children plus the
 831         * tasks I'm ptracing.
 832         */
 833        struct list_head children;      /* list of my children */
 834        struct list_head sibling;       /* linkage in my parent's children list */
 835        struct task_struct *group_leader;       /* threadgroup leader */
 836
 837        /* PID/PID hash table linkage. */
 838        struct pid_link pids[PIDTYPE_MAX];
 839        struct list_head thread_group;
 840
 841        struct completion *vfork_done;          /* for vfork() */
 842        int __user *set_child_tid;              /* CLONE_CHILD_SETTID */
 843        int __user *clear_child_tid;            /* CLONE_CHILD_CLEARTID */
 844
 845        unsigned long rt_priority;
 846        cputime_t utime, stime;
 847        unsigned long nvcsw, nivcsw; /* context switch counts */
 848        struct timespec start_time;
 849/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
 850        unsigned long min_flt, maj_flt;
 851
 852        cputime_t it_prof_expires, it_virt_expires;
 853        unsigned long long it_sched_expires;
 854        struct list_head cpu_timers[3];
 855
 856/* process credentials */
 857        uid_t uid,euid,suid,fsuid;
 858        gid_t gid,egid,sgid,fsgid;
 859        struct group_info *group_info;
 860        kernel_cap_t   cap_effective, cap_inheritable, cap_permitted;
 861        unsigned keep_capabilities:1;
 862        struct user_struct *user;
 863#ifdef CONFIG_KEYS
 864        struct key *request_key_auth;   /* assumed request_key authority */
 865        struct key *thread_keyring;     /* keyring private to this thread */
 866        unsigned char jit_keyring;      /* default keyring to attach requested keys to */
 867#endif
 868        int oomkilladj; /* OOM kill score adjustment (bit shift). */
 869        char comm[TASK_COMM_LEN]; /* executable name excluding path
 870                                     - access with [gs]et_task_comm (which lock
 871                                       it with task_lock())
 872                                     - initialized normally by flush_old_exec */
 873/* file system info */
 874        int link_count, total_link_count;
 875/* ipc stuff */
 876        struct sysv_sem sysvsem;
 877/* CPU-specific state of this task */
 878        struct thread_struct thread;
 879/* filesystem information */
 880        struct fs_struct *fs;
 881/* open file information */
 882        struct files_struct *files;
 883/* namespace */
 884        struct namespace *namespace;
 885/* signal handlers */
 886        struct signal_struct *signal;
 887        struct sighand_struct *sighand;
 888
 889        sigset_t blocked, real_blocked;
 890        sigset_t saved_sigmask;         /* To be restored with TIF_RESTORE_SIGMASK */
 891        struct sigpending pending;
 892
 893        unsigned long sas_ss_sp;
 894        size_t sas_ss_size;
 895        int (*notifier)(void *priv);
 896        void *notifier_data;
 897        sigset_t *notifier_mask;
 898        
 899        void *security;
 900        struct audit_context *audit_context;
 901        seccomp_t seccomp;
 902
 903/* Thread group tracking */
 904        u32 parent_exec_id;
 905        u32 self_exec_id;
 906/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
 907        spinlock_t alloc_lock;
 908
 909        /* Protection of the PI data structures: */
 910        spinlock_t pi_lock;
 911
 912#ifdef CONFIG_RT_MUTEXES
 913        /* PI waiters blocked on a rt_mutex held by this task */
 914        struct plist_head pi_waiters;
 915        /* Deadlock detection and priority inheritance handling */
 916        struct rt_mutex_waiter *pi_blocked_on;
 917#endif
 918
 919#ifdef CONFIG_DEBUG_MUTEXES
 920        /* mutex deadlock detection */
 921        struct mutex_waiter *blocked_on;
 922#endif
 923#ifdef CONFIG_TRACE_IRQFLAGS
 924        unsigned int irq_events;
 925        int hardirqs_enabled;
 926        unsigned long hardirq_enable_ip;
 927        unsigned int hardirq_enable_event;
 928        unsigned long hardirq_disable_ip;
 929        unsigned int hardirq_disable_event;
 930        int softirqs_enabled;
 931        unsigned long softirq_disable_ip;
 932        unsigned int softirq_disable_event;
 933        unsigned long softirq_enable_ip;
 934        unsigned int softirq_enable_event;
 935        int hardirq_context;
 936        int softirq_context;
 937#endif
 938#ifdef CONFIG_LOCKDEP
 939# define MAX_LOCK_DEPTH 30UL
 940        u64 curr_chain_key;
 941        int lockdep_depth;
 942        struct held_lock held_locks[MAX_LOCK_DEPTH];
 943        unsigned int lockdep_recursion;
 944#endif
 945
 946/* journalling filesystem info */
 947        void *journal_info;
 948
 949/* VM state */
 950        struct reclaim_state *reclaim_state;
 951
 952        struct backing_dev_info *backing_dev_info;
 953
 954        struct io_context *io_context;
 955
 956        unsigned long ptrace_message;
 957        siginfo_t *last_siginfo; /* For ptrace use.  */
 958/*
 959 * current io wait handle: wait queue entry to use for io waits
 960 * If this thread is processing aio, this points at the waitqueue
 961 * inside the currently handled kiocb. It may be NULL (i.e. default
 962 * to a stack based synchronous wait) if its doing sync IO.
 963 */
 964        wait_queue_t *io_wait;
 965/* i/o counters(bytes read/written, #syscalls */
 966        u64 rchar, wchar, syscr, syscw;
 967#if defined(CONFIG_BSD_PROCESS_ACCT)
 968        u64 acct_rss_mem1;      /* accumulated rss usage */
 969        u64 acct_vm_mem1;       /* accumulated virtual memory usage */
 970        clock_t acct_stimexpd;  /* clock_t-converted stime since last update */
 971#endif
 972#ifdef CONFIG_NUMA
 973        struct mempolicy *mempolicy;
 974        short il_next;
 975#endif
 976#ifdef CONFIG_CPUSETS
 977        struct cpuset *cpuset;
 978        nodemask_t mems_allowed;
 979        int cpuset_mems_generation;
 980        int cpuset_mem_spread_rotor;
 981#endif
 982        struct robust_list_head __user *robust_list;
 983#ifdef CONFIG_COMPAT
 984        struct compat_robust_list_head __user *compat_robust_list;
 985#endif
 986        struct list_head pi_state_list;
 987        struct futex_pi_state *pi_state_cache;
 988
 989        atomic_t fs_excl;       /* holding fs exclusive resources */
 990        struct rcu_head rcu;
 991
 992        /*
 993         * cache last used pipe for splice
 994         */
 995        struct pipe_inode_info *splice_pipe;
 996#ifdef  CONFIG_TASK_DELAY_ACCT
 997        struct task_delay_info *delays;
 998#endif
 999};
1000
1001static inline pid_t process_group(struct task_struct *tsk)
1002{
1003        return tsk->signal->pgrp;
1004}
1005
1006/**
1007 * pid_alive - check that a task structure is not stale
1008 * @p: Task structure to be checked.
1009 *
1010 * Test if a process is not yet dead (at most zombie state)
1011 * If pid_alive fails, then pointers within the task structure
1012 * can be stale and must not be dereferenced.
1013 */
1014static inline int pid_alive(struct task_struct *p)
1015{
1016        return p->pids[PIDTYPE_PID].pid != NULL;
1017}
1018
1019extern void free_task(struct task_struct *tsk);
1020#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1021
1022extern void __put_task_struct(struct task_struct *t);
1023
1024static inline void put_task_struct(struct task_struct *t)
1025{
1026        if (atomic_dec_and_test(&t->usage))
1027                __put_task_struct(t);
1028}
1029
1030/*
1031 * Per process flags
1032 */
1033#define PF_ALIGNWARN    0x00000001      /* Print alignment warning msgs */
1034                                        /* Not implemented yet, only for 486*/
1035#define PF_STARTING     0x00000002      /* being created */
1036#define PF_EXITING      0x00000004      /* getting shut down */
1037#define PF_DEAD         0x00000008      /* Dead */
1038#define PF_FORKNOEXEC   0x00000040      /* forked but didn't exec */
1039#define PF_SUPERPRIV    0x00000100      /* used super-user privileges */
1040#define PF_DUMPCORE     0x00000200      /* dumped core */
1041#define PF_SIGNALED     0x00000400      /* killed by a signal */
1042#define PF_MEMALLOC     0x00000800      /* Allocating memory */
1043#define PF_FLUSHER      0x00001000      /* responsible for disk writeback */
1044#define PF_USED_MATH    0x00002000      /* if unset the fpu must be initialized before use */
1045#define PF_FREEZE       0x00004000      /* this task is being frozen for suspend now */
1046#define PF_NOFREEZE     0x00008000      /* this thread should not be frozen */
1047#define PF_FROZEN       0x00010000      /* frozen for system suspend */
1048#define PF_FSTRANS      0x00020000      /* inside a filesystem transaction */
1049#define PF_KSWAPD       0x00040000      /* I am kswapd */
1050#define PF_SWAPOFF      0x00080000      /* I am in swapoff */
1051#define PF_LESS_THROTTLE 0x00100000     /* Throttle me less: I clean memory */
1052#define PF_BORROWED_MM  0x00200000      /* I am a kthread doing use_mm */
1053#define PF_RANDOMIZE    0x00400000      /* randomize virtual address space */
1054#define PF_SWAPWRITE    0x00800000      /* Allowed to write to swap */
1055#define PF_SPREAD_PAGE  0x01000000      /* Spread page cache over cpuset */
1056#define PF_SPREAD_SLAB  0x02000000      /* Spread some slab caches over cpuset */
1057#define PF_MEMPOLICY    0x10000000      /* Non-default NUMA mempolicy */
1058#define PF_MUTEX_TESTER 0x20000000      /* Thread belongs to the rt mutex tester */
1059
1060/*
1061 * Only the _current_ task can read/write to tsk->flags, but other
1062 * tasks can access tsk->flags in readonly mode for example
1063 * with tsk_used_math (like during threaded core dumping).
1064 * There is however an exception to this rule during ptrace
1065 * or during fork: the ptracer task is allowed to write to the
1066 * child->flags of its traced child (same goes for fork, the parent
1067 * can write to the child->flags), because we're guaranteed the
1068 * child is not running and in turn not changing child->flags
1069 * at the same time the parent does it.
1070 */
1071#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1072#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1073#define clear_used_math() clear_stopped_child_used_math(current)
1074#define set_used_math() set_stopped_child_used_math(current)
1075#define conditional_stopped_child_used_math(condition, child) \
1076        do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1077#define conditional_used_math(condition) \
1078        conditional_stopped_child_used_math(condition, current)
1079#define copy_to_stopped_child_used_math(child) \
1080        do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1081/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1082#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1083#define used_math() tsk_used_math(current)
1084
1085#ifdef CONFIG_SMP
1086extern int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask);
1087#else
1088static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1089{
1090        if (!cpu_isset(0, new_mask))
1091                return -EINVAL;
1092        return 0;
1093}
1094#endif
1095
1096extern unsigned long long sched_clock(void);
1097extern unsigned long long
1098current_sched_time(const struct task_struct *current_task);
1099
1100/* sched_exec is called by processes performing an exec */
1101#ifdef CONFIG_SMP
1102extern void sched_exec(void);
1103#else
1104#define sched_exec()   {}
1105#endif
1106
1107#ifdef CONFIG_HOTPLUG_CPU
1108extern void idle_task_exit(void);
1109#else
1110static inline void idle_task_exit(void) {}
1111#endif
1112
1113extern void sched_idle_next(void);
1114
1115#ifdef CONFIG_RT_MUTEXES
1116extern int rt_mutex_getprio(struct task_struct *p);
1117extern void rt_mutex_setprio(struct task_struct *p, int prio);
1118extern void rt_mutex_adjust_pi(struct task_struct *p);
1119#else
1120static inline int rt_mutex_getprio(struct task_struct *p)
1121{
1122        return p->normal_prio;
1123}
1124# define rt_mutex_adjust_pi(p)          do { } while (0)
1125#endif
1126
1127extern void set_user_nice(struct task_struct *p, long nice);
1128extern int task_prio(const struct task_struct *p);
1129extern int task_nice(const struct task_struct *p);
1130extern int can_nice(const struct task_struct *p, const int nice);
1131extern int task_curr(const struct task_struct *p);
1132extern int idle_cpu(int cpu);
1133extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1134extern struct task_struct *idle_task(int cpu);
1135extern struct task_struct *curr_task(int cpu);
1136extern void set_curr_task(int cpu, struct task_struct *p);
1137
1138void yield(void);
1139
1140/*
1141 * The default (Linux) execution domain.
1142 */
1143extern struct exec_domain       default_exec_domain;
1144
1145union thread_union {
1146        struct thread_info thread_info;
1147        unsigned long stack[THREAD_SIZE/sizeof(long)];
1148};
1149
1150#ifndef __HAVE_ARCH_KSTACK_END
1151static inline int kstack_end(void *addr)
1152{
1153        /* Reliable end of stack detection:
1154         * Some APM bios versions misalign the stack
1155         */
1156        return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1157}
1158#endif
1159
1160extern union thread_union init_thread_union;
1161extern struct task_struct init_task;
1162
1163extern struct   mm_struct init_mm;
1164
1165#define find_task_by_pid(nr)    find_task_by_pid_type(PIDTYPE_PID, nr)
1166extern struct task_struct *find_task_by_pid_type(int type, int pid);
1167extern void set_special_pids(pid_t session, pid_t pgrp);
1168extern void __set_special_pids(pid_t session, pid_t pgrp);
1169
1170/* per-UID process charging. */
1171extern struct user_struct * alloc_uid(uid_t);
1172static inline struct user_struct *get_uid(struct user_struct *u)
1173{
1174        atomic_inc(&u->__count);
1175        return u;
1176}
1177extern void free_uid(struct user_struct *);
1178extern void switch_uid(struct user_struct *);
1179
1180#include <asm/current.h>
1181
1182extern void do_timer(struct pt_regs *);
1183
1184extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state));
1185extern int FASTCALL(wake_up_process(struct task_struct * tsk));
1186extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
1187                                                unsigned long clone_flags));
1188#ifdef CONFIG_SMP
1189 extern void kick_process(struct task_struct *tsk);
1190#else
1191 static inline void kick_process(struct task_struct *tsk) { }
1192#endif
1193extern void FASTCALL(sched_fork(struct task_struct * p, int clone_flags));
1194extern void FASTCALL(sched_exit(struct task_struct * p));
1195
1196extern int in_group_p(gid_t);
1197extern int in_egroup_p(gid_t);
1198
1199extern void proc_caches_init(void);
1200extern void flush_signals(struct task_struct *);
1201extern void flush_signal_handlers(struct task_struct *, int force_default);
1202extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1203
1204static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1205{
1206        unsigned long flags;
1207        int ret;
1208
1209        spin_lock_irqsave(&tsk->sighand->siglock, flags);
1210        ret = dequeue_signal(tsk, mask, info);
1211        spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1212
1213        return ret;
1214}       
1215
1216extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1217                              sigset_t *mask);
1218extern void unblock_all_signals(void);
1219extern void release_task(struct task_struct * p);
1220extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1221extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
1222extern int force_sigsegv(int, struct task_struct *);
1223extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1224extern int __kill_pg_info(int sig, struct siginfo *info, pid_t pgrp);
1225extern int kill_pg_info(int, struct siginfo *, pid_t);
1226extern int kill_proc_info(int, struct siginfo *, pid_t);
1227extern int kill_proc_info_as_uid(int, struct siginfo *, pid_t, uid_t, uid_t, u32);
1228extern void do_notify_parent(struct task_struct *, int);
1229extern void force_sig(int, struct task_struct *);
1230extern void force_sig_specific(int, struct task_struct *);
1231extern int send_sig(int, struct task_struct *, int);
1232extern void zap_other_threads(struct task_struct *p);
1233extern int kill_pg(pid_t, int, int);
1234extern int kill_proc(pid_t, int, int);
1235extern struct sigqueue *sigqueue_alloc(void);
1236extern void sigqueue_free(struct sigqueue *);
1237extern int send_sigqueue(int, struct sigqueue *,  struct task_struct *);
1238extern int send_group_sigqueue(int, struct sigqueue *,  struct task_struct *);
1239extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
1240extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1241
1242/* These can be the second arg to send_sig_info/send_group_sig_info.  */
1243#define SEND_SIG_NOINFO ((struct siginfo *) 0)
1244#define SEND_SIG_PRIV   ((struct siginfo *) 1)
1245#define SEND_SIG_FORCED ((struct siginfo *) 2)
1246
1247static inline int is_si_special(const struct siginfo *info)
1248{
1249        return info <= SEND_SIG_FORCED;
1250}
1251
1252/* True if we are on the alternate signal stack.  */
1253
1254static inline int on_sig_stack(unsigned long sp)
1255{
1256        return (sp - current->sas_ss_sp < current->sas_ss_size);
1257}
1258
1259static inline int sas_ss_flags(unsigned long sp)
1260{
1261        return (current->sas_ss_size == 0 ? SS_DISABLE
1262                : on_sig_stack(sp) ? SS_ONSTACK : 0);
1263}
1264
1265/*
1266 * Routines for handling mm_structs
1267 */
1268extern struct mm_struct * mm_alloc(void);
1269
1270/* mmdrop drops the mm and the page tables */
1271extern void FASTCALL(__mmdrop(struct mm_struct *));
1272static inline void mmdrop(struct mm_struct * mm)
1273{
1274        if (atomic_dec_and_test(&mm->mm_count))
1275                __mmdrop(mm);
1276}
1277
1278/* mmput gets rid of the mappings and all user-space */
1279extern void mmput(struct mm_struct *);
1280/* Grab a reference to a task's mm, if it is not already going away */
1281extern struct mm_struct *get_task_mm(struct task_struct *task);
1282/* Remove the current tasks stale references to the old mm_struct */
1283extern void mm_release(struct task_struct *, struct mm_struct *);
1284
1285extern int  copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1286extern void flush_thread(void);
1287extern void exit_thread(void);
1288
1289extern void exit_files(struct task_struct *);
1290extern void __cleanup_signal(struct signal_struct *);
1291extern void __cleanup_sighand(struct sighand_struct *);
1292extern void exit_itimers(struct signal_struct *);
1293
1294extern NORET_TYPE void do_group_exit(int);
1295
1296extern void daemonize(const char *, ...);
1297extern int allow_signal(int);
1298extern int disallow_signal(int);
1299extern struct task_struct *child_reaper;
1300
1301extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1302extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1303struct task_struct *fork_idle(int);
1304
1305extern void set_task_comm(struct task_struct *tsk, char *from);
1306extern void get_task_comm(char *to, struct task_struct *tsk);
1307
1308#ifdef CONFIG_SMP
1309extern void wait_task_inactive(struct task_struct * p);
1310#else
1311#define wait_task_inactive(p)   do { } while (0)
1312#endif
1313
1314#define remove_parent(p)        list_del_init(&(p)->sibling)
1315#define add_parent(p)           list_add_tail(&(p)->sibling,&(p)->parent->children)
1316
1317#define next_task(p)    list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
1318
1319#define for_each_process(p) \
1320        for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1321
1322/*
1323 * Careful: do_each_thread/while_each_thread is a double loop so
1324 *          'break' will not work as expected - use goto instead.
1325 */
1326#define do_each_thread(g, t) \
1327        for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1328
1329#define while_each_thread(g, t) \
1330        while ((t = next_thread(t)) != g)
1331
1332/* de_thread depends on thread_group_leader not being a pid based check */
1333#define thread_group_leader(p)  (p == p->group_leader)
1334
1335static inline struct task_struct *next_thread(const struct task_struct *p)
1336{
1337        return list_entry(rcu_dereference(p->thread_group.next),
1338                          struct task_struct, thread_group);
1339}
1340
1341static inline int thread_group_empty(struct task_struct *p)
1342{
1343        return list_empty(&p->thread_group);
1344}
1345
1346#define delay_group_leader(p) \
1347                (thread_group_leader(p) && !thread_group_empty(p))
1348
1349/*
1350 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
1351 * subscriptions and synchronises with wait4().  Also used in procfs.  Also
1352 * pins the final release of task.io_context.  Also protects ->cpuset.
1353 *
1354 * Nests both inside and outside of read_lock(&tasklist_lock).
1355 * It must not be nested with write_lock_irq(&tasklist_lock),
1356 * neither inside nor outside.
1357 */
1358static inline void task_lock(struct task_struct *p)
1359{
1360        spin_lock(&p->alloc_lock);
1361}
1362
1363static inline void task_unlock(struct task_struct *p)
1364{
1365        spin_unlock(&p->alloc_lock);
1366}
1367
1368extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
1369                                                        unsigned long *flags);
1370
1371static inline void unlock_task_sighand(struct task_struct *tsk,
1372                                                unsigned long *flags)
1373{
1374        spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
1375}
1376
1377#ifndef __HAVE_THREAD_FUNCTIONS
1378
1379#define task_thread_info(task) (task)->thread_info
1380#define task_stack_page(task) ((void*)((task)->thread_info))
1381
1382static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
1383{
1384        *task_thread_info(p) = *task_thread_info(org);
1385        task_thread_info(p)->task = p;
1386}
1387
1388static inline unsigned long *end_of_stack(struct task_struct *p)
1389{
1390        return (unsigned long *)(p->thread_info + 1);
1391}
1392
1393#endif
1394
1395/* set thread flags in other task's structures
1396 * - see asm/thread_info.h for TIF_xxxx flags available
1397 */
1398static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1399{
1400        set_ti_thread_flag(task_thread_info(tsk), flag);
1401}
1402
1403static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1404{
1405        clear_ti_thread_flag(task_thread_info(tsk), flag);
1406}
1407
1408static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1409{
1410        return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1411}
1412
1413static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1414{
1415        return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1416}
1417
1418static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1419{
1420        return test_ti_thread_flag(task_thread_info(tsk), flag);
1421}
1422
1423static inline void set_tsk_need_resched(struct task_struct *tsk)
1424{
1425        set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1426}
1427
1428static inline void clear_tsk_need_resched(struct task_struct *tsk)
1429{
1430        clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1431}
1432
1433static inline int signal_pending(struct task_struct *p)
1434{
1435        return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1436}
1437  
1438static inline int need_resched(void)
1439{
1440        return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1441}
1442
1443/*
1444 * cond_resched() and cond_resched_lock(): latency reduction via
1445 * explicit rescheduling in places that are safe. The return
1446 * value indicates whether a reschedule was done in fact.
1447 * cond_resched_lock() will drop the spinlock before scheduling,
1448 * cond_resched_softirq() will enable bhs before scheduling.
1449 */
1450extern int cond_resched(void);
1451extern int cond_resched_lock(spinlock_t * lock);
1452extern int cond_resched_softirq(void);
1453
1454/*
1455 * Does a critical section need to be broken due to another
1456 * task waiting?:
1457 */
1458#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
1459# define need_lockbreak(lock) ((lock)->break_lock)
1460#else
1461# define need_lockbreak(lock) 0
1462#endif
1463
1464/*
1465 * Does a critical section need to be broken due to another
1466 * task waiting or preemption being signalled:
1467 */
1468static inline int lock_need_resched(spinlock_t *lock)
1469{
1470        if (need_lockbreak(lock) || need_resched())
1471                return 1;
1472        return 0;
1473}
1474
1475/* Reevaluate whether the task has signals pending delivery.
1476   This is required every time the blocked sigset_t changes.
1477   callers must hold sighand->siglock.  */
1478
1479extern FASTCALL(void recalc_sigpending_tsk(struct task_struct *t));
1480extern void recalc_sigpending(void);
1481
1482extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1483
1484/*
1485 * Wrappers for p->thread_info->cpu access. No-op on UP.
1486 */
1487#ifdef CONFIG_SMP
1488
1489static inline unsigned int task_cpu(const struct task_struct *p)
1490{
1491        return task_thread_info(p)->cpu;
1492}
1493
1494static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1495{
1496        task_thread_info(p)->cpu = cpu;
1497}
1498
1499#else
1500
1501static inline unsigned int task_cpu(const struct task_struct *p)
1502{
1503        return 0;
1504}
1505
1506static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1507{
1508}
1509
1510#endif /* CONFIG_SMP */
1511
1512#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1513extern void arch_pick_mmap_layout(struct mm_struct *mm);
1514#else
1515static inline void arch_pick_mmap_layout(struct mm_struct *mm)
1516{
1517        mm->mmap_base = TASK_UNMAPPED_BASE;
1518        mm->get_unmapped_area = arch_get_unmapped_area;
1519        mm->unmap_area = arch_unmap_area;
1520}
1521#endif
1522
1523extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
1524extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
1525
1526#include <linux/sysdev.h>
1527extern int sched_mc_power_savings, sched_smt_power_savings;
1528extern struct sysdev_attribute attr_sched_mc_power_savings, attr_sched_smt_power_savings;
1529extern int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls);
1530
1531extern void normalize_rt_tasks(void);
1532
1533#ifdef CONFIG_PM
1534/*
1535 * Check if a process has been frozen
1536 */
1537static inline int frozen(struct task_struct *p)
1538{
1539        return p->flags & PF_FROZEN;
1540}
1541
1542/*
1543 * Check if there is a request to freeze a process
1544 */
1545static inline int freezing(struct task_struct *p)
1546{
1547        return p->flags & PF_FREEZE;
1548}
1549
1550/*
1551 * Request that a process be frozen
1552 * FIXME: SMP problem. We may not modify other process' flags!
1553 */
1554static inline void freeze(struct task_struct *p)
1555{
1556        p->flags |= PF_FREEZE;
1557}
1558
1559/*
1560 * Sometimes we may need to cancel the previous 'freeze' request
1561 */
1562static inline void do_not_freeze(struct task_struct *p)
1563{
1564        p->flags &= ~PF_FREEZE;
1565}
1566
1567/*
1568 * Wake up a frozen process
1569 */
1570static inline int thaw_process(struct task_struct *p)
1571{
1572        if (frozen(p)) {
1573                p->flags &= ~PF_FROZEN;
1574                wake_up_process(p);
1575                return 1;
1576        }
1577        return 0;
1578}
1579
1580/*
1581 * freezing is complete, mark process as frozen
1582 */
1583static inline void frozen_process(struct task_struct *p)
1584{
1585        p->flags = (p->flags & ~PF_FREEZE) | PF_FROZEN;
1586}
1587
1588extern void refrigerator(void);
1589extern int freeze_processes(void);
1590extern void thaw_processes(void);
1591
1592static inline int try_to_freeze(void)
1593{
1594        if (freezing(current)) {
1595                refrigerator();
1596                return 1;
1597        } else
1598                return 0;
1599}
1600#else
1601static inline int frozen(struct task_struct *p) { return 0; }
1602static inline int freezing(struct task_struct *p) { return 0; }
1603static inline void freeze(struct task_struct *p) { BUG(); }
1604static inline int thaw_process(struct task_struct *p) { return 1; }
1605static inline void frozen_process(struct task_struct *p) { BUG(); }
1606
1607static inline void refrigerator(void) {}
1608static inline int freeze_processes(void) { BUG(); return 0; }
1609static inline void thaw_processes(void) {}
1610
1611static inline int try_to_freeze(void) { return 0; }
1612
1613#endif /* CONFIG_PM */
1614#endif /* __KERNEL__ */
1615
1616#endif
1617
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