linux/include/linux/sched.h
<<
>>
Prefs
   1#ifndef _LINUX_SCHED_H
   2#define _LINUX_SCHED_H
   3
   4#include <asm/param.h>  /* for HZ */
   5
   6#include <linux/config.h>
   7#include <linux/capability.h>
   8#include <linux/threads.h>
   9#include <linux/kernel.h>
  10#include <linux/types.h>
  11#include <linux/timex.h>
  12#include <linux/jiffies.h>
  13#include <linux/rbtree.h>
  14#include <linux/thread_info.h>
  15#include <linux/cpumask.h>
  16#include <linux/errno.h>
  17#include <linux/nodemask.h>
  18
  19#include <asm/system.h>
  20#include <asm/semaphore.h>
  21#include <asm/page.h>
  22#include <asm/ptrace.h>
  23#include <asm/mmu.h>
  24#include <asm/cputime.h>
  25
  26#include <linux/smp.h>
  27#include <linux/sem.h>
  28#include <linux/signal.h>
  29#include <linux/securebits.h>
  30#include <linux/fs_struct.h>
  31#include <linux/compiler.h>
  32#include <linux/completion.h>
  33#include <linux/pid.h>
  34#include <linux/percpu.h>
  35#include <linux/topology.h>
  36#include <linux/seccomp.h>
  37#include <linux/rcupdate.h>
  38#include <linux/futex.h>
  39
  40#include <linux/auxvec.h>       /* For AT_VECTOR_SIZE */
  41
  42struct exec_domain;
  43
  44/*
  45 * cloning flags:
  46 */
  47#define CSIGNAL         0x000000ff      /* signal mask to be sent at exit */
  48#define CLONE_VM        0x00000100      /* set if VM shared between processes */
  49#define CLONE_FS        0x00000200      /* set if fs info shared between processes */
  50#define CLONE_FILES     0x00000400      /* set if open files shared between processes */
  51#define CLONE_SIGHAND   0x00000800      /* set if signal handlers and blocked signals shared */
  52#define CLONE_PTRACE    0x00002000      /* set if we want to let tracing continue on the child too */
  53#define CLONE_VFORK     0x00004000      /* set if the parent wants the child to wake it up on mm_release */
  54#define CLONE_PARENT    0x00008000      /* set if we want to have the same parent as the cloner */
  55#define CLONE_THREAD    0x00010000      /* Same thread group? */
  56#define CLONE_NEWNS     0x00020000      /* New namespace group? */
  57#define CLONE_SYSVSEM   0x00040000      /* share system V SEM_UNDO semantics */
  58#define CLONE_SETTLS    0x00080000      /* create a new TLS for the child */
  59#define CLONE_PARENT_SETTID     0x00100000      /* set the TID in the parent */
  60#define CLONE_CHILD_CLEARTID    0x00200000      /* clear the TID in the child */
  61#define CLONE_DETACHED          0x00400000      /* Unused, ignored */
  62#define CLONE_UNTRACED          0x00800000      /* set if the tracing process can't force CLONE_PTRACE on this clone */
  63#define CLONE_CHILD_SETTID      0x01000000      /* set the TID in the child */
  64#define CLONE_STOPPED           0x02000000      /* Start in stopped state */
  65
  66/*
  67 * List of flags we want to share for kernel threads,
  68 * if only because they are not used by them anyway.
  69 */
  70#define CLONE_KERNEL    (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
  71
  72/*
  73 * These are the constant used to fake the fixed-point load-average
  74 * counting. Some notes:
  75 *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
  76 *    a load-average precision of 10 bits integer + 11 bits fractional
  77 *  - if you want to count load-averages more often, you need more
  78 *    precision, or rounding will get you. With 2-second counting freq,
  79 *    the EXP_n values would be 1981, 2034 and 2043 if still using only
  80 *    11 bit fractions.
  81 */
  82extern unsigned long avenrun[];         /* Load averages */
  83
  84#define FSHIFT          11              /* nr of bits of precision */
  85#define FIXED_1         (1<<FSHIFT)     /* 1.0 as fixed-point */
  86#define LOAD_FREQ       (5*HZ)          /* 5 sec intervals */
  87#define EXP_1           1884            /* 1/exp(5sec/1min) as fixed-point */
  88#define EXP_5           2014            /* 1/exp(5sec/5min) */
  89#define EXP_15          2037            /* 1/exp(5sec/15min) */
  90
  91#define CALC_LOAD(load,exp,n) \
  92        load *= exp; \
  93        load += n*(FIXED_1-exp); \
  94        load >>= FSHIFT;
  95
  96extern unsigned long total_forks;
  97extern int nr_threads;
  98extern int last_pid;
  99DECLARE_PER_CPU(unsigned long, process_counts);
 100extern int nr_processes(void);
 101extern unsigned long nr_running(void);
 102extern unsigned long nr_uninterruptible(void);
 103extern unsigned long nr_active(void);
 104extern unsigned long nr_iowait(void);
 105
 106#include <linux/time.h>
 107#include <linux/param.h>
 108#include <linux/resource.h>
 109#include <linux/timer.h>
 110#include <linux/hrtimer.h>
 111
 112#include <asm/processor.h>
 113
 114/*
 115 * Task state bitmask. NOTE! These bits are also
 116 * encoded in fs/proc/array.c: get_task_state().
 117 *
 118 * We have two separate sets of flags: task->state
 119 * is about runnability, while task->exit_state are
 120 * about the task exiting. Confusing, but this way
 121 * modifying one set can't modify the other one by
 122 * mistake.
 123 */
 124#define TASK_RUNNING            0
 125#define TASK_INTERRUPTIBLE      1
 126#define TASK_UNINTERRUPTIBLE    2
 127#define TASK_STOPPED            4
 128#define TASK_TRACED             8
 129/* in tsk->exit_state */
 130#define EXIT_ZOMBIE             16
 131#define EXIT_DEAD               32
 132/* in tsk->state again */
 133#define TASK_NONINTERACTIVE     64
 134
 135#define __set_task_state(tsk, state_value)              \
 136        do { (tsk)->state = (state_value); } while (0)
 137#define set_task_state(tsk, state_value)                \
 138        set_mb((tsk)->state, (state_value))
 139
 140/*
 141 * set_current_state() includes a barrier so that the write of current->state
 142 * is correctly serialised wrt the caller's subsequent test of whether to
 143 * actually sleep:
 144 *
 145 *      set_current_state(TASK_UNINTERRUPTIBLE);
 146 *      if (do_i_need_to_sleep())
 147 *              schedule();
 148 *
 149 * If the caller does not need such serialisation then use __set_current_state()
 150 */
 151#define __set_current_state(state_value)                        \
 152        do { current->state = (state_value); } while (0)
 153#define set_current_state(state_value)          \
 154        set_mb(current->state, (state_value))
 155
 156/* Task command name length */
 157#define TASK_COMM_LEN 16
 158
 159/*
 160 * Scheduling policies
 161 */
 162#define SCHED_NORMAL            0
 163#define SCHED_FIFO              1
 164#define SCHED_RR                2
 165#define SCHED_BATCH             3
 166
 167struct sched_param {
 168        int sched_priority;
 169};
 170
 171#ifdef __KERNEL__
 172
 173#include <linux/spinlock.h>
 174
 175/*
 176 * This serializes "schedule()" and also protects
 177 * the run-queue from deletions/modifications (but
 178 * _adding_ to the beginning of the run-queue has
 179 * a separate lock).
 180 */
 181extern rwlock_t tasklist_lock;
 182extern spinlock_t mmlist_lock;
 183
 184typedef struct task_struct task_t;
 185
 186extern void sched_init(void);
 187extern void sched_init_smp(void);
 188extern void init_idle(task_t *idle, int cpu);
 189
 190extern cpumask_t nohz_cpu_mask;
 191
 192extern void show_state(void);
 193extern void show_regs(struct pt_regs *);
 194
 195/*
 196 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
 197 * task), SP is the stack pointer of the first frame that should be shown in the back
 198 * trace (or NULL if the entire call-chain of the task should be shown).
 199 */
 200extern void show_stack(struct task_struct *task, unsigned long *sp);
 201
 202void io_schedule(void);
 203long io_schedule_timeout(long timeout);
 204
 205extern void cpu_init (void);
 206extern void trap_init(void);
 207extern void update_process_times(int user);
 208extern void scheduler_tick(void);
 209
 210#ifdef CONFIG_DETECT_SOFTLOCKUP
 211extern void softlockup_tick(void);
 212extern void spawn_softlockup_task(void);
 213extern void touch_softlockup_watchdog(void);
 214#else
 215static inline void softlockup_tick(void)
 216{
 217}
 218static inline void spawn_softlockup_task(void)
 219{
 220}
 221static inline void touch_softlockup_watchdog(void)
 222{
 223}
 224#endif
 225
 226
 227/* Attach to any functions which should be ignored in wchan output. */
 228#define __sched         __attribute__((__section__(".sched.text")))
 229/* Is this address in the __sched functions? */
 230extern int in_sched_functions(unsigned long addr);
 231
 232#define MAX_SCHEDULE_TIMEOUT    LONG_MAX
 233extern signed long FASTCALL(schedule_timeout(signed long timeout));
 234extern signed long schedule_timeout_interruptible(signed long timeout);
 235extern signed long schedule_timeout_uninterruptible(signed long timeout);
 236asmlinkage void schedule(void);
 237
 238struct namespace;
 239
 240/* Maximum number of active map areas.. This is a random (large) number */
 241#define DEFAULT_MAX_MAP_COUNT   65536
 242
 243extern int sysctl_max_map_count;
 244
 245#include <linux/aio.h>
 246
 247extern unsigned long
 248arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
 249                       unsigned long, unsigned long);
 250extern unsigned long
 251arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
 252                          unsigned long len, unsigned long pgoff,
 253                          unsigned long flags);
 254extern void arch_unmap_area(struct mm_struct *, unsigned long);
 255extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
 256
 257#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
 258/*
 259 * The mm counters are not protected by its page_table_lock,
 260 * so must be incremented atomically.
 261 */
 262#define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
 263#define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
 264#define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
 265#define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
 266#define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
 267typedef atomic_long_t mm_counter_t;
 268
 269#else  /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
 270/*
 271 * The mm counters are protected by its page_table_lock,
 272 * so can be incremented directly.
 273 */
 274#define set_mm_counter(mm, member, value) (mm)->_##member = (value)
 275#define get_mm_counter(mm, member) ((mm)->_##member)
 276#define add_mm_counter(mm, member, value) (mm)->_##member += (value)
 277#define inc_mm_counter(mm, member) (mm)->_##member++
 278#define dec_mm_counter(mm, member) (mm)->_##member--
 279typedef unsigned long mm_counter_t;
 280
 281#endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
 282
 283#define get_mm_rss(mm)                                  \
 284        (get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
 285#define update_hiwater_rss(mm)  do {                    \
 286        unsigned long _rss = get_mm_rss(mm);            \
 287        if ((mm)->hiwater_rss < _rss)                   \
 288                (mm)->hiwater_rss = _rss;               \
 289} while (0)
 290#define update_hiwater_vm(mm)   do {                    \
 291        if ((mm)->hiwater_vm < (mm)->total_vm)          \
 292                (mm)->hiwater_vm = (mm)->total_vm;      \
 293} while (0)
 294
 295struct mm_struct {
 296        struct vm_area_struct * mmap;           /* list of VMAs */
 297        struct rb_root mm_rb;
 298        struct vm_area_struct * mmap_cache;     /* last find_vma result */
 299        unsigned long (*get_unmapped_area) (struct file *filp,
 300                                unsigned long addr, unsigned long len,
 301                                unsigned long pgoff, unsigned long flags);
 302        void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
 303        unsigned long mmap_base;                /* base of mmap area */
 304        unsigned long task_size;                /* size of task vm space */
 305        unsigned long cached_hole_size;         /* if non-zero, the largest hole below free_area_cache */
 306        unsigned long free_area_cache;          /* first hole of size cached_hole_size or larger */
 307        pgd_t * pgd;
 308        atomic_t mm_users;                      /* How many users with user space? */
 309        atomic_t mm_count;                      /* How many references to "struct mm_struct" (users count as 1) */
 310        int map_count;                          /* number of VMAs */
 311        struct rw_semaphore mmap_sem;
 312        spinlock_t page_table_lock;             /* Protects page tables and some counters */
 313
 314        struct list_head mmlist;                /* List of maybe swapped mm's.  These are globally strung
 315                                                 * together off init_mm.mmlist, and are protected
 316                                                 * by mmlist_lock
 317                                                 */
 318
 319        /* Special counters, in some configurations protected by the
 320         * page_table_lock, in other configurations by being atomic.
 321         */
 322        mm_counter_t _file_rss;
 323        mm_counter_t _anon_rss;
 324
 325        unsigned long hiwater_rss;      /* High-watermark of RSS usage */
 326        unsigned long hiwater_vm;       /* High-water virtual memory usage */
 327
 328        unsigned long total_vm, locked_vm, shared_vm, exec_vm;
 329        unsigned long stack_vm, reserved_vm, def_flags, nr_ptes;
 330        unsigned long start_code, end_code, start_data, end_data;
 331        unsigned long start_brk, brk, start_stack;
 332        unsigned long arg_start, arg_end, env_start, env_end;
 333
 334        unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
 335
 336        unsigned dumpable:2;
 337        cpumask_t cpu_vm_mask;
 338
 339        /* Architecture-specific MM context */
 340        mm_context_t context;
 341
 342        /* Token based thrashing protection. */
 343        unsigned long swap_token_time;
 344        char recent_pagein;
 345
 346        /* coredumping support */
 347        int core_waiters;
 348        struct completion *core_startup_done, core_done;
 349
 350        /* aio bits */
 351        rwlock_t                ioctx_list_lock;
 352        struct kioctx           *ioctx_list;
 353};
 354
 355struct sighand_struct {
 356        atomic_t                count;
 357        struct k_sigaction      action[_NSIG];
 358        spinlock_t              siglock;
 359};
 360
 361/*
 362 * NOTE! "signal_struct" does not have it's own
 363 * locking, because a shared signal_struct always
 364 * implies a shared sighand_struct, so locking
 365 * sighand_struct is always a proper superset of
 366 * the locking of signal_struct.
 367 */
 368struct signal_struct {
 369        atomic_t                count;
 370        atomic_t                live;
 371
 372        wait_queue_head_t       wait_chldexit;  /* for wait4() */
 373
 374        /* current thread group signal load-balancing target: */
 375        task_t                  *curr_target;
 376
 377        /* shared signal handling: */
 378        struct sigpending       shared_pending;
 379
 380        /* thread group exit support */
 381        int                     group_exit_code;
 382        /* overloaded:
 383         * - notify group_exit_task when ->count is equal to notify_count
 384         * - everyone except group_exit_task is stopped during signal delivery
 385         *   of fatal signals, group_exit_task processes the signal.
 386         */
 387        struct task_struct      *group_exit_task;
 388        int                     notify_count;
 389
 390        /* thread group stop support, overloads group_exit_code too */
 391        int                     group_stop_count;
 392        unsigned int            flags; /* see SIGNAL_* flags below */
 393
 394        /* POSIX.1b Interval Timers */
 395        struct list_head posix_timers;
 396
 397        /* ITIMER_REAL timer for the process */
 398        struct hrtimer real_timer;
 399        struct task_struct *tsk;
 400        ktime_t it_real_incr;
 401
 402        /* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
 403        cputime_t it_prof_expires, it_virt_expires;
 404        cputime_t it_prof_incr, it_virt_incr;
 405
 406        /* job control IDs */
 407        pid_t pgrp;
 408        pid_t tty_old_pgrp;
 409        pid_t session;
 410        /* boolean value for session group leader */
 411        int leader;
 412
 413        struct tty_struct *tty; /* NULL if no tty */
 414
 415        /*
 416         * Cumulative resource counters for dead threads in the group,
 417         * and for reaped dead child processes forked by this group.
 418         * Live threads maintain their own counters and add to these
 419         * in __exit_signal, except for the group leader.
 420         */
 421        cputime_t utime, stime, cutime, cstime;
 422        unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
 423        unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
 424
 425        /*
 426         * Cumulative ns of scheduled CPU time for dead threads in the
 427         * group, not including a zombie group leader.  (This only differs
 428         * from jiffies_to_ns(utime + stime) if sched_clock uses something
 429         * other than jiffies.)
 430         */
 431        unsigned long long sched_time;
 432
 433        /*
 434         * We don't bother to synchronize most readers of this at all,
 435         * because there is no reader checking a limit that actually needs
 436         * to get both rlim_cur and rlim_max atomically, and either one
 437         * alone is a single word that can safely be read normally.
 438         * getrlimit/setrlimit use task_lock(current->group_leader) to
 439         * protect this instead of the siglock, because they really
 440         * have no need to disable irqs.
 441         */
 442        struct rlimit rlim[RLIM_NLIMITS];
 443
 444        struct list_head cpu_timers[3];
 445
 446        /* keep the process-shared keyrings here so that they do the right
 447         * thing in threads created with CLONE_THREAD */
 448#ifdef CONFIG_KEYS
 449        struct key *session_keyring;    /* keyring inherited over fork */
 450        struct key *process_keyring;    /* keyring private to this process */
 451#endif
 452};
 453
 454/* Context switch must be unlocked if interrupts are to be enabled */
 455#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
 456# define __ARCH_WANT_UNLOCKED_CTXSW
 457#endif
 458
 459/*
 460 * Bits in flags field of signal_struct.
 461 */
 462#define SIGNAL_STOP_STOPPED     0x00000001 /* job control stop in effect */
 463#define SIGNAL_STOP_DEQUEUED    0x00000002 /* stop signal dequeued */
 464#define SIGNAL_STOP_CONTINUED   0x00000004 /* SIGCONT since WCONTINUED reap */
 465#define SIGNAL_GROUP_EXIT       0x00000008 /* group exit in progress */
 466
 467
 468/*
 469 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
 470 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
 471 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
 472 * values are inverted: lower p->prio value means higher priority.
 473 *
 474 * The MAX_USER_RT_PRIO value allows the actual maximum
 475 * RT priority to be separate from the value exported to
 476 * user-space.  This allows kernel threads to set their
 477 * priority to a value higher than any user task. Note:
 478 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
 479 */
 480
 481#define MAX_USER_RT_PRIO        100
 482#define MAX_RT_PRIO             MAX_USER_RT_PRIO
 483
 484#define MAX_PRIO                (MAX_RT_PRIO + 40)
 485
 486#define rt_task(p)              (unlikely((p)->prio < MAX_RT_PRIO))
 487#define batch_task(p)           (unlikely((p)->policy == SCHED_BATCH))
 488
 489/*
 490 * Some day this will be a full-fledged user tracking system..
 491 */
 492struct user_struct {
 493        atomic_t __count;       /* reference count */
 494        atomic_t processes;     /* How many processes does this user have? */
 495        atomic_t files;         /* How many open files does this user have? */
 496        atomic_t sigpending;    /* How many pending signals does this user have? */
 497#ifdef CONFIG_INOTIFY
 498        atomic_t inotify_watches; /* How many inotify watches does this user have? */
 499        atomic_t inotify_devs;  /* How many inotify devs does this user have opened? */
 500#endif
 501        /* protected by mq_lock */
 502        unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
 503        unsigned long locked_shm; /* How many pages of mlocked shm ? */
 504
 505#ifdef CONFIG_KEYS
 506        struct key *uid_keyring;        /* UID specific keyring */
 507        struct key *session_keyring;    /* UID's default session keyring */
 508#endif
 509
 510        /* Hash table maintenance information */
 511        struct list_head uidhash_list;
 512        uid_t uid;
 513};
 514
 515extern struct user_struct *find_user(uid_t);
 516
 517extern struct user_struct root_user;
 518#define INIT_USER (&root_user)
 519
 520typedef struct prio_array prio_array_t;
 521struct backing_dev_info;
 522struct reclaim_state;
 523
 524#ifdef CONFIG_SCHEDSTATS
 525struct sched_info {
 526        /* cumulative counters */
 527        unsigned long   cpu_time,       /* time spent on the cpu */
 528                        run_delay,      /* time spent waiting on a runqueue */
 529                        pcnt;           /* # of timeslices run on this cpu */
 530
 531        /* timestamps */
 532        unsigned long   last_arrival,   /* when we last ran on a cpu */
 533                        last_queued;    /* when we were last queued to run */
 534};
 535
 536extern struct file_operations proc_schedstat_operations;
 537#endif
 538
 539enum idle_type
 540{
 541        SCHED_IDLE,
 542        NOT_IDLE,
 543        NEWLY_IDLE,
 544        MAX_IDLE_TYPES
 545};
 546
 547/*
 548 * sched-domains (multiprocessor balancing) declarations:
 549 */
 550#ifdef CONFIG_SMP
 551#define SCHED_LOAD_SCALE        128UL   /* increase resolution of load */
 552
 553#define SD_LOAD_BALANCE         1       /* Do load balancing on this domain. */
 554#define SD_BALANCE_NEWIDLE      2       /* Balance when about to become idle */
 555#define SD_BALANCE_EXEC         4       /* Balance on exec */
 556#define SD_BALANCE_FORK         8       /* Balance on fork, clone */
 557#define SD_WAKE_IDLE            16      /* Wake to idle CPU on task wakeup */
 558#define SD_WAKE_AFFINE          32      /* Wake task to waking CPU */
 559#define SD_WAKE_BALANCE         64      /* Perform balancing at task wakeup */
 560#define SD_SHARE_CPUPOWER       128     /* Domain members share cpu power */
 561
 562struct sched_group {
 563        struct sched_group *next;       /* Must be a circular list */
 564        cpumask_t cpumask;
 565
 566        /*
 567         * CPU power of this group, SCHED_LOAD_SCALE being max power for a
 568         * single CPU. This is read only (except for setup, hotplug CPU).
 569         */
 570        unsigned long cpu_power;
 571};
 572
 573struct sched_domain {
 574        /* These fields must be setup */
 575        struct sched_domain *parent;    /* top domain must be null terminated */
 576        struct sched_group *groups;     /* the balancing groups of the domain */
 577        cpumask_t span;                 /* span of all CPUs in this domain */
 578        unsigned long min_interval;     /* Minimum balance interval ms */
 579        unsigned long max_interval;     /* Maximum balance interval ms */
 580        unsigned int busy_factor;       /* less balancing by factor if busy */
 581        unsigned int imbalance_pct;     /* No balance until over watermark */
 582        unsigned long long cache_hot_time; /* Task considered cache hot (ns) */
 583        unsigned int cache_nice_tries;  /* Leave cache hot tasks for # tries */
 584        unsigned int per_cpu_gain;      /* CPU % gained by adding domain cpus */
 585        unsigned int busy_idx;
 586        unsigned int idle_idx;
 587        unsigned int newidle_idx;
 588        unsigned int wake_idx;
 589        unsigned int forkexec_idx;
 590        int flags;                      /* See SD_* */
 591
 592        /* Runtime fields. */
 593        unsigned long last_balance;     /* init to jiffies. units in jiffies */
 594        unsigned int balance_interval;  /* initialise to 1. units in ms. */
 595        unsigned int nr_balance_failed; /* initialise to 0 */
 596
 597#ifdef CONFIG_SCHEDSTATS
 598        /* load_balance() stats */
 599        unsigned long lb_cnt[MAX_IDLE_TYPES];
 600        unsigned long lb_failed[MAX_IDLE_TYPES];
 601        unsigned long lb_balanced[MAX_IDLE_TYPES];
 602        unsigned long lb_imbalance[MAX_IDLE_TYPES];
 603        unsigned long lb_gained[MAX_IDLE_TYPES];
 604        unsigned long lb_hot_gained[MAX_IDLE_TYPES];
 605        unsigned long lb_nobusyg[MAX_IDLE_TYPES];
 606        unsigned long lb_nobusyq[MAX_IDLE_TYPES];
 607
 608        /* Active load balancing */
 609        unsigned long alb_cnt;
 610        unsigned long alb_failed;
 611        unsigned long alb_pushed;
 612
 613        /* SD_BALANCE_EXEC stats */
 614        unsigned long sbe_cnt;
 615        unsigned long sbe_balanced;
 616        unsigned long sbe_pushed;
 617
 618        /* SD_BALANCE_FORK stats */
 619        unsigned long sbf_cnt;
 620        unsigned long sbf_balanced;
 621        unsigned long sbf_pushed;
 622
 623        /* try_to_wake_up() stats */
 624        unsigned long ttwu_wake_remote;
 625        unsigned long ttwu_move_affine;
 626        unsigned long ttwu_move_balance;
 627#endif
 628};
 629
 630extern void partition_sched_domains(cpumask_t *partition1,
 631                                    cpumask_t *partition2);
 632
 633/*
 634 * Maximum cache size the migration-costs auto-tuning code will
 635 * search from:
 636 */
 637extern unsigned int max_cache_size;
 638
 639#endif  /* CONFIG_SMP */
 640
 641
 642struct io_context;                      /* See blkdev.h */
 643void exit_io_context(void);
 644struct cpuset;
 645
 646#define NGROUPS_SMALL           32
 647#define NGROUPS_PER_BLOCK       ((int)(PAGE_SIZE / sizeof(gid_t)))
 648struct group_info {
 649        int ngroups;
 650        atomic_t usage;
 651        gid_t small_block[NGROUPS_SMALL];
 652        int nblocks;
 653        gid_t *blocks[0];
 654};
 655
 656/*
 657 * get_group_info() must be called with the owning task locked (via task_lock())
 658 * when task != current.  The reason being that the vast majority of callers are
 659 * looking at current->group_info, which can not be changed except by the
 660 * current task.  Changing current->group_info requires the task lock, too.
 661 */
 662#define get_group_info(group_info) do { \
 663        atomic_inc(&(group_info)->usage); \
 664} while (0)
 665
 666#define put_group_info(group_info) do { \
 667        if (atomic_dec_and_test(&(group_info)->usage)) \
 668                groups_free(group_info); \
 669} while (0)
 670
 671extern struct group_info *groups_alloc(int gidsetsize);
 672extern void groups_free(struct group_info *group_info);
 673extern int set_current_groups(struct group_info *group_info);
 674extern int groups_search(struct group_info *group_info, gid_t grp);
 675/* access the groups "array" with this macro */
 676#define GROUP_AT(gi, i) \
 677    ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
 678
 679#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
 680extern void prefetch_stack(struct task_struct*);
 681#else
 682static inline void prefetch_stack(struct task_struct *t) { }
 683#endif
 684
 685struct audit_context;           /* See audit.c */
 686struct mempolicy;
 687struct pipe_inode_info;
 688
 689enum sleep_type {
 690        SLEEP_NORMAL,
 691        SLEEP_NONINTERACTIVE,
 692        SLEEP_INTERACTIVE,
 693        SLEEP_INTERRUPTED,
 694};
 695
 696struct task_struct {
 697        volatile long state;    /* -1 unrunnable, 0 runnable, >0 stopped */
 698        struct thread_info *thread_info;
 699        atomic_t usage;
 700        unsigned long flags;    /* per process flags, defined below */
 701        unsigned long ptrace;
 702
 703        int lock_depth;         /* BKL lock depth */
 704
 705#if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW)
 706        int oncpu;
 707#endif
 708        int prio, static_prio;
 709        struct list_head run_list;
 710        prio_array_t *array;
 711
 712        unsigned short ioprio;
 713        unsigned int btrace_seq;
 714
 715        unsigned long sleep_avg;
 716        unsigned long long timestamp, last_ran;
 717        unsigned long long sched_time; /* sched_clock time spent running */
 718        enum sleep_type sleep_type;
 719
 720        unsigned long policy;
 721        cpumask_t cpus_allowed;
 722        unsigned int time_slice, first_time_slice;
 723
 724#ifdef CONFIG_SCHEDSTATS
 725        struct sched_info sched_info;
 726#endif
 727
 728        struct list_head tasks;
 729        /*
 730         * ptrace_list/ptrace_children forms the list of my children
 731         * that were stolen by a ptracer.
 732         */
 733        struct list_head ptrace_children;
 734        struct list_head ptrace_list;
 735
 736        struct mm_struct *mm, *active_mm;
 737
 738/* task state */
 739        struct linux_binfmt *binfmt;
 740        long exit_state;
 741        int exit_code, exit_signal;
 742        int pdeath_signal;  /*  The signal sent when the parent dies  */
 743        /* ??? */
 744        unsigned long personality;
 745        unsigned did_exec:1;
 746        pid_t pid;
 747        pid_t tgid;
 748        /* 
 749         * pointers to (original) parent process, youngest child, younger sibling,
 750         * older sibling, respectively.  (p->father can be replaced with 
 751         * p->parent->pid)
 752         */
 753        struct task_struct *real_parent; /* real parent process (when being debugged) */
 754        struct task_struct *parent;     /* parent process */
 755        /*
 756         * children/sibling forms the list of my children plus the
 757         * tasks I'm ptracing.
 758         */
 759        struct list_head children;      /* list of my children */
 760        struct list_head sibling;       /* linkage in my parent's children list */
 761        struct task_struct *group_leader;       /* threadgroup leader */
 762
 763        /* PID/PID hash table linkage. */
 764        struct pid_link pids[PIDTYPE_MAX];
 765        struct list_head thread_group;
 766
 767        struct completion *vfork_done;          /* for vfork() */
 768        int __user *set_child_tid;              /* CLONE_CHILD_SETTID */
 769        int __user *clear_child_tid;            /* CLONE_CHILD_CLEARTID */
 770
 771        unsigned long rt_priority;
 772        cputime_t utime, stime;
 773        unsigned long nvcsw, nivcsw; /* context switch counts */
 774        struct timespec start_time;
 775/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
 776        unsigned long min_flt, maj_flt;
 777
 778        cputime_t it_prof_expires, it_virt_expires;
 779        unsigned long long it_sched_expires;
 780        struct list_head cpu_timers[3];
 781
 782/* process credentials */
 783        uid_t uid,euid,suid,fsuid;
 784        gid_t gid,egid,sgid,fsgid;
 785        struct group_info *group_info;
 786        kernel_cap_t   cap_effective, cap_inheritable, cap_permitted;
 787        unsigned keep_capabilities:1;
 788        struct user_struct *user;
 789#ifdef CONFIG_KEYS
 790        struct key *request_key_auth;   /* assumed request_key authority */
 791        struct key *thread_keyring;     /* keyring private to this thread */
 792        unsigned char jit_keyring;      /* default keyring to attach requested keys to */
 793#endif
 794        int oomkilladj; /* OOM kill score adjustment (bit shift). */
 795        char comm[TASK_COMM_LEN]; /* executable name excluding path
 796                                     - access with [gs]et_task_comm (which lock
 797                                       it with task_lock())
 798                                     - initialized normally by flush_old_exec */
 799/* file system info */
 800        int link_count, total_link_count;
 801/* ipc stuff */
 802        struct sysv_sem sysvsem;
 803/* CPU-specific state of this task */
 804        struct thread_struct thread;
 805/* filesystem information */
 806        struct fs_struct *fs;
 807/* open file information */
 808        struct files_struct *files;
 809/* namespace */
 810        struct namespace *namespace;
 811/* signal handlers */
 812        struct signal_struct *signal;
 813        struct sighand_struct *sighand;
 814
 815        sigset_t blocked, real_blocked;
 816        sigset_t saved_sigmask;         /* To be restored with TIF_RESTORE_SIGMASK */
 817        struct sigpending pending;
 818
 819        unsigned long sas_ss_sp;
 820        size_t sas_ss_size;
 821        int (*notifier)(void *priv);
 822        void *notifier_data;
 823        sigset_t *notifier_mask;
 824        
 825        void *security;
 826        struct audit_context *audit_context;
 827        seccomp_t seccomp;
 828
 829/* Thread group tracking */
 830        u32 parent_exec_id;
 831        u32 self_exec_id;
 832/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
 833        spinlock_t alloc_lock;
 834/* Protection of proc_dentry: nesting proc_lock, dcache_lock, write_lock_irq(&tasklist_lock); */
 835        spinlock_t proc_lock;
 836
 837#ifdef CONFIG_DEBUG_MUTEXES
 838        /* mutex deadlock detection */
 839        struct mutex_waiter *blocked_on;
 840#endif
 841
 842/* journalling filesystem info */
 843        void *journal_info;
 844
 845/* VM state */
 846        struct reclaim_state *reclaim_state;
 847
 848        struct dentry *proc_dentry;
 849        struct backing_dev_info *backing_dev_info;
 850
 851        struct io_context *io_context;
 852
 853        unsigned long ptrace_message;
 854        siginfo_t *last_siginfo; /* For ptrace use.  */
 855/*
 856 * current io wait handle: wait queue entry to use for io waits
 857 * If this thread is processing aio, this points at the waitqueue
 858 * inside the currently handled kiocb. It may be NULL (i.e. default
 859 * to a stack based synchronous wait) if its doing sync IO.
 860 */
 861        wait_queue_t *io_wait;
 862/* i/o counters(bytes read/written, #syscalls */
 863        u64 rchar, wchar, syscr, syscw;
 864#if defined(CONFIG_BSD_PROCESS_ACCT)
 865        u64 acct_rss_mem1;      /* accumulated rss usage */
 866        u64 acct_vm_mem1;       /* accumulated virtual memory usage */
 867        clock_t acct_stimexpd;  /* clock_t-converted stime since last update */
 868#endif
 869#ifdef CONFIG_NUMA
 870        struct mempolicy *mempolicy;
 871        short il_next;
 872#endif
 873#ifdef CONFIG_CPUSETS
 874        struct cpuset *cpuset;
 875        nodemask_t mems_allowed;
 876        int cpuset_mems_generation;
 877        int cpuset_mem_spread_rotor;
 878#endif
 879        struct robust_list_head __user *robust_list;
 880#ifdef CONFIG_COMPAT
 881        struct compat_robust_list_head __user *compat_robust_list;
 882#endif
 883
 884        atomic_t fs_excl;       /* holding fs exclusive resources */
 885        struct rcu_head rcu;
 886
 887        /*
 888         * cache last used pipe for splice
 889         */
 890        struct pipe_inode_info *splice_pipe;
 891};
 892
 893static inline pid_t process_group(struct task_struct *tsk)
 894{
 895        return tsk->signal->pgrp;
 896}
 897
 898/**
 899 * pid_alive - check that a task structure is not stale
 900 * @p: Task structure to be checked.
 901 *
 902 * Test if a process is not yet dead (at most zombie state)
 903 * If pid_alive fails, then pointers within the task structure
 904 * can be stale and must not be dereferenced.
 905 */
 906static inline int pid_alive(struct task_struct *p)
 907{
 908        return p->pids[PIDTYPE_PID].pid != NULL;
 909}
 910
 911extern void free_task(struct task_struct *tsk);
 912#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
 913
 914extern void __put_task_struct(struct task_struct *t);
 915
 916static inline void put_task_struct(struct task_struct *t)
 917{
 918        if (atomic_dec_and_test(&t->usage))
 919                __put_task_struct(t);
 920}
 921
 922/*
 923 * Per process flags
 924 */
 925#define PF_ALIGNWARN    0x00000001      /* Print alignment warning msgs */
 926                                        /* Not implemented yet, only for 486*/
 927#define PF_STARTING     0x00000002      /* being created */
 928#define PF_EXITING      0x00000004      /* getting shut down */
 929#define PF_DEAD         0x00000008      /* Dead */
 930#define PF_FORKNOEXEC   0x00000040      /* forked but didn't exec */
 931#define PF_SUPERPRIV    0x00000100      /* used super-user privileges */
 932#define PF_DUMPCORE     0x00000200      /* dumped core */
 933#define PF_SIGNALED     0x00000400      /* killed by a signal */
 934#define PF_MEMALLOC     0x00000800      /* Allocating memory */
 935#define PF_FLUSHER      0x00001000      /* responsible for disk writeback */
 936#define PF_USED_MATH    0x00002000      /* if unset the fpu must be initialized before use */
 937#define PF_FREEZE       0x00004000      /* this task is being frozen for suspend now */
 938#define PF_NOFREEZE     0x00008000      /* this thread should not be frozen */
 939#define PF_FROZEN       0x00010000      /* frozen for system suspend */
 940#define PF_FSTRANS      0x00020000      /* inside a filesystem transaction */
 941#define PF_KSWAPD       0x00040000      /* I am kswapd */
 942#define PF_SWAPOFF      0x00080000      /* I am in swapoff */
 943#define PF_LESS_THROTTLE 0x00100000     /* Throttle me less: I clean memory */
 944#define PF_SYNCWRITE    0x00200000      /* I am doing a sync write */
 945#define PF_BORROWED_MM  0x00400000      /* I am a kthread doing use_mm */
 946#define PF_RANDOMIZE    0x00800000      /* randomize virtual address space */
 947#define PF_SWAPWRITE    0x01000000      /* Allowed to write to swap */
 948#define PF_SPREAD_PAGE  0x04000000      /* Spread page cache over cpuset */
 949#define PF_SPREAD_SLAB  0x08000000      /* Spread some slab caches over cpuset */
 950#define PF_MEMPOLICY    0x10000000      /* Non-default NUMA mempolicy */
 951
 952/*
 953 * Only the _current_ task can read/write to tsk->flags, but other
 954 * tasks can access tsk->flags in readonly mode for example
 955 * with tsk_used_math (like during threaded core dumping).
 956 * There is however an exception to this rule during ptrace
 957 * or during fork: the ptracer task is allowed to write to the
 958 * child->flags of its traced child (same goes for fork, the parent
 959 * can write to the child->flags), because we're guaranteed the
 960 * child is not running and in turn not changing child->flags
 961 * at the same time the parent does it.
 962 */
 963#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
 964#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
 965#define clear_used_math() clear_stopped_child_used_math(current)
 966#define set_used_math() set_stopped_child_used_math(current)
 967#define conditional_stopped_child_used_math(condition, child) \
 968        do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
 969#define conditional_used_math(condition) \
 970        conditional_stopped_child_used_math(condition, current)
 971#define copy_to_stopped_child_used_math(child) \
 972        do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
 973/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
 974#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
 975#define used_math() tsk_used_math(current)
 976
 977#ifdef CONFIG_SMP
 978extern int set_cpus_allowed(task_t *p, cpumask_t new_mask);
 979#else
 980static inline int set_cpus_allowed(task_t *p, cpumask_t new_mask)
 981{
 982        if (!cpu_isset(0, new_mask))
 983                return -EINVAL;
 984        return 0;
 985}
 986#endif
 987
 988extern unsigned long long sched_clock(void);
 989extern unsigned long long current_sched_time(const task_t *current_task);
 990
 991/* sched_exec is called by processes performing an exec */
 992#ifdef CONFIG_SMP
 993extern void sched_exec(void);
 994#else
 995#define sched_exec()   {}
 996#endif
 997
 998#ifdef CONFIG_HOTPLUG_CPU
 999extern void idle_task_exit(void);
1000#else
1001static inline void idle_task_exit(void) {}
1002#endif
1003
1004extern void sched_idle_next(void);
1005extern void set_user_nice(task_t *p, long nice);
1006extern int task_prio(const task_t *p);
1007extern int task_nice(const task_t *p);
1008extern int can_nice(const task_t *p, const int nice);
1009extern int task_curr(const task_t *p);
1010extern int idle_cpu(int cpu);
1011extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1012extern task_t *idle_task(int cpu);
1013extern task_t *curr_task(int cpu);
1014extern void set_curr_task(int cpu, task_t *p);
1015
1016void yield(void);
1017
1018/*
1019 * The default (Linux) execution domain.
1020 */
1021extern struct exec_domain       default_exec_domain;
1022
1023union thread_union {
1024        struct thread_info thread_info;
1025        unsigned long stack[THREAD_SIZE/sizeof(long)];
1026};
1027
1028#ifndef __HAVE_ARCH_KSTACK_END
1029static inline int kstack_end(void *addr)
1030{
1031        /* Reliable end of stack detection:
1032         * Some APM bios versions misalign the stack
1033         */
1034        return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1035}
1036#endif
1037
1038extern union thread_union init_thread_union;
1039extern struct task_struct init_task;
1040
1041extern struct   mm_struct init_mm;
1042
1043#define find_task_by_pid(nr)    find_task_by_pid_type(PIDTYPE_PID, nr)
1044extern struct task_struct *find_task_by_pid_type(int type, int pid);
1045extern void set_special_pids(pid_t session, pid_t pgrp);
1046extern void __set_special_pids(pid_t session, pid_t pgrp);
1047
1048/* per-UID process charging. */
1049extern struct user_struct * alloc_uid(uid_t);
1050static inline struct user_struct *get_uid(struct user_struct *u)
1051{
1052        atomic_inc(&u->__count);
1053        return u;
1054}
1055extern void free_uid(struct user_struct *);
1056extern void switch_uid(struct user_struct *);
1057
1058#include <asm/current.h>
1059
1060extern void do_timer(struct pt_regs *);
1061
1062extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state));
1063extern int FASTCALL(wake_up_process(struct task_struct * tsk));
1064extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
1065                                                unsigned long clone_flags));
1066#ifdef CONFIG_SMP
1067 extern void kick_process(struct task_struct *tsk);
1068#else
1069 static inline void kick_process(struct task_struct *tsk) { }
1070#endif
1071extern void FASTCALL(sched_fork(task_t * p, int clone_flags));
1072extern void FASTCALL(sched_exit(task_t * p));
1073
1074extern int in_group_p(gid_t);
1075extern int in_egroup_p(gid_t);
1076
1077extern void proc_caches_init(void);
1078extern void flush_signals(struct task_struct *);
1079extern void flush_signal_handlers(struct task_struct *, int force_default);
1080extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1081
1082static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1083{
1084        unsigned long flags;
1085        int ret;
1086
1087        spin_lock_irqsave(&tsk->sighand->siglock, flags);
1088        ret = dequeue_signal(tsk, mask, info);
1089        spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1090
1091        return ret;
1092}       
1093
1094extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1095                              sigset_t *mask);
1096extern void unblock_all_signals(void);
1097extern void release_task(struct task_struct * p);
1098extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1099extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
1100extern int force_sigsegv(int, struct task_struct *);
1101extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1102extern int __kill_pg_info(int sig, struct siginfo *info, pid_t pgrp);
1103extern int kill_pg_info(int, struct siginfo *, pid_t);
1104extern int kill_proc_info(int, struct siginfo *, pid_t);
1105extern int kill_proc_info_as_uid(int, struct siginfo *, pid_t, uid_t, uid_t);
1106extern void do_notify_parent(struct task_struct *, int);
1107extern void force_sig(int, struct task_struct *);
1108extern void force_sig_specific(int, struct task_struct *);
1109extern int send_sig(int, struct task_struct *, int);
1110extern void zap_other_threads(struct task_struct *p);
1111extern int kill_pg(pid_t, int, int);
1112extern int kill_proc(pid_t, int, int);
1113extern struct sigqueue *sigqueue_alloc(void);
1114extern void sigqueue_free(struct sigqueue *);
1115extern int send_sigqueue(int, struct sigqueue *,  struct task_struct *);
1116extern int send_group_sigqueue(int, struct sigqueue *,  struct task_struct *);
1117extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
1118extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1119
1120/* These can be the second arg to send_sig_info/send_group_sig_info.  */
1121#define SEND_SIG_NOINFO ((struct siginfo *) 0)
1122#define SEND_SIG_PRIV   ((struct siginfo *) 1)
1123#define SEND_SIG_FORCED ((struct siginfo *) 2)
1124
1125static inline int is_si_special(const struct siginfo *info)
1126{
1127        return info <= SEND_SIG_FORCED;
1128}
1129
1130/* True if we are on the alternate signal stack.  */
1131
1132static inline int on_sig_stack(unsigned long sp)
1133{
1134        return (sp - current->sas_ss_sp < current->sas_ss_size);
1135}
1136
1137static inline int sas_ss_flags(unsigned long sp)
1138{
1139        return (current->sas_ss_size == 0 ? SS_DISABLE
1140                : on_sig_stack(sp) ? SS_ONSTACK : 0);
1141}
1142
1143/*
1144 * Routines for handling mm_structs
1145 */
1146extern struct mm_struct * mm_alloc(void);
1147
1148/* mmdrop drops the mm and the page tables */
1149extern void FASTCALL(__mmdrop(struct mm_struct *));
1150static inline void mmdrop(struct mm_struct * mm)
1151{
1152        if (atomic_dec_and_test(&mm->mm_count))
1153                __mmdrop(mm);
1154}
1155
1156/* mmput gets rid of the mappings and all user-space */
1157extern void mmput(struct mm_struct *);
1158/* Grab a reference to a task's mm, if it is not already going away */
1159extern struct mm_struct *get_task_mm(struct task_struct *task);
1160/* Remove the current tasks stale references to the old mm_struct */
1161extern void mm_release(struct task_struct *, struct mm_struct *);
1162
1163extern int  copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1164extern void flush_thread(void);
1165extern void exit_thread(void);
1166
1167extern void exit_files(struct task_struct *);
1168extern void __cleanup_signal(struct signal_struct *);
1169extern void __cleanup_sighand(struct sighand_struct *);
1170extern void exit_itimers(struct signal_struct *);
1171
1172extern NORET_TYPE void do_group_exit(int);
1173
1174extern void daemonize(const char *, ...);
1175extern int allow_signal(int);
1176extern int disallow_signal(int);
1177extern task_t *child_reaper;
1178
1179extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1180extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1181task_t *fork_idle(int);
1182
1183extern void set_task_comm(struct task_struct *tsk, char *from);
1184extern void get_task_comm(char *to, struct task_struct *tsk);
1185
1186#ifdef CONFIG_SMP
1187extern void wait_task_inactive(task_t * p);
1188#else
1189#define wait_task_inactive(p)   do { } while (0)
1190#endif
1191
1192#define remove_parent(p)        list_del_init(&(p)->sibling)
1193#define add_parent(p)           list_add_tail(&(p)->sibling,&(p)->parent->children)
1194
1195#define next_task(p)    list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
1196
1197#define for_each_process(p) \
1198        for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1199
1200/*
1201 * Careful: do_each_thread/while_each_thread is a double loop so
1202 *          'break' will not work as expected - use goto instead.
1203 */
1204#define do_each_thread(g, t) \
1205        for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1206
1207#define while_each_thread(g, t) \
1208        while ((t = next_thread(t)) != g)
1209
1210/* de_thread depends on thread_group_leader not being a pid based check */
1211#define thread_group_leader(p)  (p == p->group_leader)
1212
1213static inline task_t *next_thread(const task_t *p)
1214{
1215        return list_entry(rcu_dereference(p->thread_group.next),
1216                                task_t, thread_group);
1217}
1218
1219static inline int thread_group_empty(task_t *p)
1220{
1221        return list_empty(&p->thread_group);
1222}
1223
1224#define delay_group_leader(p) \
1225                (thread_group_leader(p) && !thread_group_empty(p))
1226
1227/*
1228 * Protects ->fs, ->files, ->mm, ->ptrace, ->group_info, ->comm, keyring
1229 * subscriptions and synchronises with wait4().  Also used in procfs.  Also
1230 * pins the final release of task.io_context.  Also protects ->cpuset.
1231 *
1232 * Nests both inside and outside of read_lock(&tasklist_lock).
1233 * It must not be nested with write_lock_irq(&tasklist_lock),
1234 * neither inside nor outside.
1235 */
1236static inline void task_lock(struct task_struct *p)
1237{
1238        spin_lock(&p->alloc_lock);
1239}
1240
1241static inline void task_unlock(struct task_struct *p)
1242{
1243        spin_unlock(&p->alloc_lock);
1244}
1245
1246extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
1247                                                        unsigned long *flags);
1248
1249static inline void unlock_task_sighand(struct task_struct *tsk,
1250                                                unsigned long *flags)
1251{
1252        spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
1253}
1254
1255#ifndef __HAVE_THREAD_FUNCTIONS
1256
1257#define task_thread_info(task) (task)->thread_info
1258#define task_stack_page(task) ((void*)((task)->thread_info))
1259
1260static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
1261{
1262        *task_thread_info(p) = *task_thread_info(org);
1263        task_thread_info(p)->task = p;
1264}
1265
1266static inline unsigned long *end_of_stack(struct task_struct *p)
1267{
1268        return (unsigned long *)(p->thread_info + 1);
1269}
1270
1271#endif
1272
1273/* set thread flags in other task's structures
1274 * - see asm/thread_info.h for TIF_xxxx flags available
1275 */
1276static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1277{
1278        set_ti_thread_flag(task_thread_info(tsk), flag);
1279}
1280
1281static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1282{
1283        clear_ti_thread_flag(task_thread_info(tsk), flag);
1284}
1285
1286static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1287{
1288        return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1289}
1290
1291static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1292{
1293        return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1294}
1295
1296static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1297{
1298        return test_ti_thread_flag(task_thread_info(tsk), flag);
1299}
1300
1301static inline void set_tsk_need_resched(struct task_struct *tsk)
1302{
1303        set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1304}
1305
1306static inline void clear_tsk_need_resched(struct task_struct *tsk)
1307{
1308        clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1309}
1310
1311static inline int signal_pending(struct task_struct *p)
1312{
1313        return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1314}
1315  
1316static inline int need_resched(void)
1317{
1318        return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1319}
1320
1321/*
1322 * cond_resched() and cond_resched_lock(): latency reduction via
1323 * explicit rescheduling in places that are safe. The return
1324 * value indicates whether a reschedule was done in fact.
1325 * cond_resched_lock() will drop the spinlock before scheduling,
1326 * cond_resched_softirq() will enable bhs before scheduling.
1327 */
1328extern int cond_resched(void);
1329extern int cond_resched_lock(spinlock_t * lock);
1330extern int cond_resched_softirq(void);
1331
1332/*
1333 * Does a critical section need to be broken due to another
1334 * task waiting?:
1335 */
1336#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
1337# define need_lockbreak(lock) ((lock)->break_lock)
1338#else
1339# define need_lockbreak(lock) 0
1340#endif
1341
1342/*
1343 * Does a critical section need to be broken due to another
1344 * task waiting or preemption being signalled:
1345 */
1346static inline int lock_need_resched(spinlock_t *lock)
1347{
1348        if (need_lockbreak(lock) || need_resched())
1349                return 1;
1350        return 0;
1351}
1352
1353/* Reevaluate whether the task has signals pending delivery.
1354   This is required every time the blocked sigset_t changes.
1355   callers must hold sighand->siglock.  */
1356
1357extern FASTCALL(void recalc_sigpending_tsk(struct task_struct *t));
1358extern void recalc_sigpending(void);
1359
1360extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1361
1362/*
1363 * Wrappers for p->thread_info->cpu access. No-op on UP.
1364 */
1365#ifdef CONFIG_SMP
1366
1367static inline unsigned int task_cpu(const struct task_struct *p)
1368{
1369        return task_thread_info(p)->cpu;
1370}
1371
1372static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1373{
1374        task_thread_info(p)->cpu = cpu;
1375}
1376
1377#else
1378
1379static inline unsigned int task_cpu(const struct task_struct *p)
1380{
1381        return 0;
1382}
1383
1384static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1385{
1386}
1387
1388#endif /* CONFIG_SMP */
1389
1390#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1391extern void arch_pick_mmap_layout(struct mm_struct *mm);
1392#else
1393static inline void arch_pick_mmap_layout(struct mm_struct *mm)
1394{
1395        mm->mmap_base = TASK_UNMAPPED_BASE;
1396        mm->get_unmapped_area = arch_get_unmapped_area;
1397        mm->unmap_area = arch_unmap_area;
1398}
1399#endif
1400
1401extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
1402extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
1403
1404extern void normalize_rt_tasks(void);
1405
1406#ifdef CONFIG_PM
1407/*
1408 * Check if a process has been frozen
1409 */
1410static inline int frozen(struct task_struct *p)
1411{
1412        return p->flags & PF_FROZEN;
1413}
1414
1415/*
1416 * Check if there is a request to freeze a process
1417 */
1418static inline int freezing(struct task_struct *p)
1419{
1420        return p->flags & PF_FREEZE;
1421}
1422
1423/*
1424 * Request that a process be frozen
1425 * FIXME: SMP problem. We may not modify other process' flags!
1426 */
1427static inline void freeze(struct task_struct *p)
1428{
1429        p->flags |= PF_FREEZE;
1430}
1431
1432/*
1433 * Wake up a frozen process
1434 */
1435static inline int thaw_process(struct task_struct *p)
1436{
1437        if (frozen(p)) {
1438                p->flags &= ~PF_FROZEN;
1439                wake_up_process(p);
1440                return 1;
1441        }
1442        return 0;
1443}
1444
1445/*
1446 * freezing is complete, mark process as frozen
1447 */
1448static inline void frozen_process(struct task_struct *p)
1449{
1450        p->flags = (p->flags & ~PF_FREEZE) | PF_FROZEN;
1451}
1452
1453extern void refrigerator(void);
1454extern int freeze_processes(void);
1455extern void thaw_processes(void);
1456
1457static inline int try_to_freeze(void)
1458{
1459        if (freezing(current)) {
1460                refrigerator();
1461                return 1;
1462        } else
1463                return 0;
1464}
1465#else
1466static inline int frozen(struct task_struct *p) { return 0; }
1467static inline int freezing(struct task_struct *p) { return 0; }
1468static inline void freeze(struct task_struct *p) { BUG(); }
1469static inline int thaw_process(struct task_struct *p) { return 1; }
1470static inline void frozen_process(struct task_struct *p) { BUG(); }
1471
1472static inline void refrigerator(void) {}
1473static inline int freeze_processes(void) { BUG(); return 0; }
1474static inline void thaw_processes(void) {}
1475
1476static inline int try_to_freeze(void) { return 0; }
1477
1478#endif /* CONFIG_PM */
1479#endif /* __KERNEL__ */
1480
1481#endif
1482