linux/include/linux/sched.h
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   1#ifndef _LINUX_SCHED_H
   2#define _LINUX_SCHED_H
   3
   4/*
   5 * cloning flags:
   6 */
   7#define CSIGNAL         0x000000ff      /* signal mask to be sent at exit */
   8#define CLONE_VM        0x00000100      /* set if VM shared between processes */
   9#define CLONE_FS        0x00000200      /* set if fs info shared between processes */
  10#define CLONE_FILES     0x00000400      /* set if open files shared between processes */
  11#define CLONE_SIGHAND   0x00000800      /* set if signal handlers and blocked signals shared */
  12#define CLONE_PTRACE    0x00002000      /* set if we want to let tracing continue on the child too */
  13#define CLONE_VFORK     0x00004000      /* set if the parent wants the child to wake it up on mm_release */
  14#define CLONE_PARENT    0x00008000      /* set if we want to have the same parent as the cloner */
  15#define CLONE_THREAD    0x00010000      /* Same thread group? */
  16#define CLONE_NEWNS     0x00020000      /* New namespace group? */
  17#define CLONE_SYSVSEM   0x00040000      /* share system V SEM_UNDO semantics */
  18#define CLONE_SETTLS    0x00080000      /* create a new TLS for the child */
  19#define CLONE_PARENT_SETTID     0x00100000      /* set the TID in the parent */
  20#define CLONE_CHILD_CLEARTID    0x00200000      /* clear the TID in the child */
  21#define CLONE_DETACHED          0x00400000      /* Unused, ignored */
  22#define CLONE_UNTRACED          0x00800000      /* set if the tracing process can't force CLONE_PTRACE on this clone */
  23#define CLONE_CHILD_SETTID      0x01000000      /* set the TID in the child */
  24#define CLONE_STOPPED           0x02000000      /* Start in stopped state */
  25#define CLONE_NEWUTS            0x04000000      /* New utsname group? */
  26#define CLONE_NEWIPC            0x08000000      /* New ipcs */
  27#define CLONE_NEWUSER           0x10000000      /* New user namespace */
  28#define CLONE_NEWPID            0x20000000      /* New pid namespace */
  29#define CLONE_NEWNET            0x40000000      /* New network namespace */
  30
  31/*
  32 * Scheduling policies
  33 */
  34#define SCHED_NORMAL            0
  35#define SCHED_FIFO              1
  36#define SCHED_RR                2
  37#define SCHED_BATCH             3
  38/* SCHED_ISO: reserved but not implemented yet */
  39#define SCHED_IDLE              5
  40
  41#ifdef __KERNEL__
  42
  43struct sched_param {
  44        int sched_priority;
  45};
  46
  47#include <asm/param.h>  /* for HZ */
  48
  49#include <linux/capability.h>
  50#include <linux/threads.h>
  51#include <linux/kernel.h>
  52#include <linux/types.h>
  53#include <linux/timex.h>
  54#include <linux/jiffies.h>
  55#include <linux/rbtree.h>
  56#include <linux/thread_info.h>
  57#include <linux/cpumask.h>
  58#include <linux/errno.h>
  59#include <linux/nodemask.h>
  60#include <linux/mm_types.h>
  61
  62#include <asm/system.h>
  63#include <asm/semaphore.h>
  64#include <asm/page.h>
  65#include <asm/ptrace.h>
  66#include <asm/cputime.h>
  67
  68#include <linux/smp.h>
  69#include <linux/sem.h>
  70#include <linux/signal.h>
  71#include <linux/securebits.h>
  72#include <linux/fs_struct.h>
  73#include <linux/compiler.h>
  74#include <linux/completion.h>
  75#include <linux/pid.h>
  76#include <linux/percpu.h>
  77#include <linux/topology.h>
  78#include <linux/proportions.h>
  79#include <linux/seccomp.h>
  80#include <linux/rcupdate.h>
  81#include <linux/futex.h>
  82#include <linux/rtmutex.h>
  83
  84#include <linux/time.h>
  85#include <linux/param.h>
  86#include <linux/resource.h>
  87#include <linux/timer.h>
  88#include <linux/hrtimer.h>
  89#include <linux/task_io_accounting.h>
  90#include <linux/kobject.h>
  91
  92#include <asm/processor.h>
  93
  94struct exec_domain;
  95struct futex_pi_state;
  96struct bio;
  97
  98/*
  99 * List of flags we want to share for kernel threads,
 100 * if only because they are not used by them anyway.
 101 */
 102#define CLONE_KERNEL    (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
 103
 104/*
 105 * These are the constant used to fake the fixed-point load-average
 106 * counting. Some notes:
 107 *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
 108 *    a load-average precision of 10 bits integer + 11 bits fractional
 109 *  - if you want to count load-averages more often, you need more
 110 *    precision, or rounding will get you. With 2-second counting freq,
 111 *    the EXP_n values would be 1981, 2034 and 2043 if still using only
 112 *    11 bit fractions.
 113 */
 114extern unsigned long avenrun[];         /* Load averages */
 115
 116#define FSHIFT          11              /* nr of bits of precision */
 117#define FIXED_1         (1<<FSHIFT)     /* 1.0 as fixed-point */
 118#define LOAD_FREQ       (5*HZ+1)        /* 5 sec intervals */
 119#define EXP_1           1884            /* 1/exp(5sec/1min) as fixed-point */
 120#define EXP_5           2014            /* 1/exp(5sec/5min) */
 121#define EXP_15          2037            /* 1/exp(5sec/15min) */
 122
 123#define CALC_LOAD(load,exp,n) \
 124        load *= exp; \
 125        load += n*(FIXED_1-exp); \
 126        load >>= FSHIFT;
 127
 128extern unsigned long total_forks;
 129extern int nr_threads;
 130DECLARE_PER_CPU(unsigned long, process_counts);
 131extern int nr_processes(void);
 132extern unsigned long nr_running(void);
 133extern unsigned long nr_uninterruptible(void);
 134extern unsigned long nr_active(void);
 135extern unsigned long nr_iowait(void);
 136extern unsigned long weighted_cpuload(const int cpu);
 137
 138struct seq_file;
 139struct cfs_rq;
 140struct task_group;
 141#ifdef CONFIG_SCHED_DEBUG
 142extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
 143extern void proc_sched_set_task(struct task_struct *p);
 144extern void
 145print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
 146#else
 147static inline void
 148proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 149{
 150}
 151static inline void proc_sched_set_task(struct task_struct *p)
 152{
 153}
 154static inline void
 155print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
 156{
 157}
 158#endif
 159
 160/*
 161 * Task state bitmask. NOTE! These bits are also
 162 * encoded in fs/proc/array.c: get_task_state().
 163 *
 164 * We have two separate sets of flags: task->state
 165 * is about runnability, while task->exit_state are
 166 * about the task exiting. Confusing, but this way
 167 * modifying one set can't modify the other one by
 168 * mistake.
 169 */
 170#define TASK_RUNNING            0
 171#define TASK_INTERRUPTIBLE      1
 172#define TASK_UNINTERRUPTIBLE    2
 173#define TASK_STOPPED            4
 174#define TASK_TRACED             8
 175/* in tsk->exit_state */
 176#define EXIT_ZOMBIE             16
 177#define EXIT_DEAD               32
 178/* in tsk->state again */
 179#define TASK_DEAD               64
 180
 181#define __set_task_state(tsk, state_value)              \
 182        do { (tsk)->state = (state_value); } while (0)
 183#define set_task_state(tsk, state_value)                \
 184        set_mb((tsk)->state, (state_value))
 185
 186/*
 187 * set_current_state() includes a barrier so that the write of current->state
 188 * is correctly serialised wrt the caller's subsequent test of whether to
 189 * actually sleep:
 190 *
 191 *      set_current_state(TASK_UNINTERRUPTIBLE);
 192 *      if (do_i_need_to_sleep())
 193 *              schedule();
 194 *
 195 * If the caller does not need such serialisation then use __set_current_state()
 196 */
 197#define __set_current_state(state_value)                        \
 198        do { current->state = (state_value); } while (0)
 199#define set_current_state(state_value)          \
 200        set_mb(current->state, (state_value))
 201
 202/* Task command name length */
 203#define TASK_COMM_LEN 16
 204
 205#include <linux/spinlock.h>
 206
 207/*
 208 * This serializes "schedule()" and also protects
 209 * the run-queue from deletions/modifications (but
 210 * _adding_ to the beginning of the run-queue has
 211 * a separate lock).
 212 */
 213extern rwlock_t tasklist_lock;
 214extern spinlock_t mmlist_lock;
 215
 216struct task_struct;
 217
 218extern void sched_init(void);
 219extern void sched_init_smp(void);
 220extern void init_idle(struct task_struct *idle, int cpu);
 221extern void init_idle_bootup_task(struct task_struct *idle);
 222
 223extern cpumask_t nohz_cpu_mask;
 224#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
 225extern int select_nohz_load_balancer(int cpu);
 226#else
 227static inline int select_nohz_load_balancer(int cpu)
 228{
 229        return 0;
 230}
 231#endif
 232
 233/*
 234 * Only dump TASK_* tasks. (0 for all tasks)
 235 */
 236extern void show_state_filter(unsigned long state_filter);
 237
 238static inline void show_state(void)
 239{
 240        show_state_filter(0);
 241}
 242
 243extern void show_regs(struct pt_regs *);
 244
 245/*
 246 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
 247 * task), SP is the stack pointer of the first frame that should be shown in the back
 248 * trace (or NULL if the entire call-chain of the task should be shown).
 249 */
 250extern void show_stack(struct task_struct *task, unsigned long *sp);
 251
 252void io_schedule(void);
 253long io_schedule_timeout(long timeout);
 254
 255extern void cpu_init (void);
 256extern void trap_init(void);
 257extern void account_process_tick(struct task_struct *task, int user);
 258extern void update_process_times(int user);
 259extern void scheduler_tick(void);
 260
 261#ifdef CONFIG_DETECT_SOFTLOCKUP
 262extern void softlockup_tick(void);
 263extern void spawn_softlockup_task(void);
 264extern void touch_softlockup_watchdog(void);
 265extern void touch_all_softlockup_watchdogs(void);
 266extern int softlockup_thresh;
 267#else
 268static inline void softlockup_tick(void)
 269{
 270}
 271static inline void spawn_softlockup_task(void)
 272{
 273}
 274static inline void touch_softlockup_watchdog(void)
 275{
 276}
 277static inline void touch_all_softlockup_watchdogs(void)
 278{
 279}
 280#endif
 281
 282
 283/* Attach to any functions which should be ignored in wchan output. */
 284#define __sched         __attribute__((__section__(".sched.text")))
 285
 286/* Linker adds these: start and end of __sched functions */
 287extern char __sched_text_start[], __sched_text_end[];
 288
 289/* Is this address in the __sched functions? */
 290extern int in_sched_functions(unsigned long addr);
 291
 292#define MAX_SCHEDULE_TIMEOUT    LONG_MAX
 293extern signed long FASTCALL(schedule_timeout(signed long timeout));
 294extern signed long schedule_timeout_interruptible(signed long timeout);
 295extern signed long schedule_timeout_uninterruptible(signed long timeout);
 296asmlinkage void schedule(void);
 297
 298struct nsproxy;
 299struct user_namespace;
 300
 301/* Maximum number of active map areas.. This is a random (large) number */
 302#define DEFAULT_MAX_MAP_COUNT   65536
 303
 304extern int sysctl_max_map_count;
 305
 306#include <linux/aio.h>
 307
 308extern unsigned long
 309arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
 310                       unsigned long, unsigned long);
 311extern unsigned long
 312arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
 313                          unsigned long len, unsigned long pgoff,
 314                          unsigned long flags);
 315extern void arch_unmap_area(struct mm_struct *, unsigned long);
 316extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
 317
 318#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
 319/*
 320 * The mm counters are not protected by its page_table_lock,
 321 * so must be incremented atomically.
 322 */
 323#define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
 324#define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
 325#define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
 326#define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
 327#define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
 328
 329#else  /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
 330/*
 331 * The mm counters are protected by its page_table_lock,
 332 * so can be incremented directly.
 333 */
 334#define set_mm_counter(mm, member, value) (mm)->_##member = (value)
 335#define get_mm_counter(mm, member) ((mm)->_##member)
 336#define add_mm_counter(mm, member, value) (mm)->_##member += (value)
 337#define inc_mm_counter(mm, member) (mm)->_##member++
 338#define dec_mm_counter(mm, member) (mm)->_##member--
 339
 340#endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
 341
 342#define get_mm_rss(mm)                                  \
 343        (get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
 344#define update_hiwater_rss(mm)  do {                    \
 345        unsigned long _rss = get_mm_rss(mm);            \
 346        if ((mm)->hiwater_rss < _rss)                   \
 347                (mm)->hiwater_rss = _rss;               \
 348} while (0)
 349#define update_hiwater_vm(mm)   do {                    \
 350        if ((mm)->hiwater_vm < (mm)->total_vm)          \
 351                (mm)->hiwater_vm = (mm)->total_vm;      \
 352} while (0)
 353
 354extern void set_dumpable(struct mm_struct *mm, int value);
 355extern int get_dumpable(struct mm_struct *mm);
 356
 357/* mm flags */
 358/* dumpable bits */
 359#define MMF_DUMPABLE      0  /* core dump is permitted */
 360#define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
 361#define MMF_DUMPABLE_BITS 2
 362
 363/* coredump filter bits */
 364#define MMF_DUMP_ANON_PRIVATE   2
 365#define MMF_DUMP_ANON_SHARED    3
 366#define MMF_DUMP_MAPPED_PRIVATE 4
 367#define MMF_DUMP_MAPPED_SHARED  5
 368#define MMF_DUMP_ELF_HEADERS    6
 369#define MMF_DUMP_FILTER_SHIFT   MMF_DUMPABLE_BITS
 370#define MMF_DUMP_FILTER_BITS    5
 371#define MMF_DUMP_FILTER_MASK \
 372        (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
 373#define MMF_DUMP_FILTER_DEFAULT \
 374        ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED))
 375
 376struct sighand_struct {
 377        atomic_t                count;
 378        struct k_sigaction      action[_NSIG];
 379        spinlock_t              siglock;
 380        wait_queue_head_t       signalfd_wqh;
 381};
 382
 383struct pacct_struct {
 384        int                     ac_flag;
 385        long                    ac_exitcode;
 386        unsigned long           ac_mem;
 387        cputime_t               ac_utime, ac_stime;
 388        unsigned long           ac_minflt, ac_majflt;
 389};
 390
 391/*
 392 * NOTE! "signal_struct" does not have it's own
 393 * locking, because a shared signal_struct always
 394 * implies a shared sighand_struct, so locking
 395 * sighand_struct is always a proper superset of
 396 * the locking of signal_struct.
 397 */
 398struct signal_struct {
 399        atomic_t                count;
 400        atomic_t                live;
 401
 402        wait_queue_head_t       wait_chldexit;  /* for wait4() */
 403
 404        /* current thread group signal load-balancing target: */
 405        struct task_struct      *curr_target;
 406
 407        /* shared signal handling: */
 408        struct sigpending       shared_pending;
 409
 410        /* thread group exit support */
 411        int                     group_exit_code;
 412        /* overloaded:
 413         * - notify group_exit_task when ->count is equal to notify_count
 414         * - everyone except group_exit_task is stopped during signal delivery
 415         *   of fatal signals, group_exit_task processes the signal.
 416         */
 417        struct task_struct      *group_exit_task;
 418        int                     notify_count;
 419
 420        /* thread group stop support, overloads group_exit_code too */
 421        int                     group_stop_count;
 422        unsigned int            flags; /* see SIGNAL_* flags below */
 423
 424        /* POSIX.1b Interval Timers */
 425        struct list_head posix_timers;
 426
 427        /* ITIMER_REAL timer for the process */
 428        struct hrtimer real_timer;
 429        struct task_struct *tsk;
 430        ktime_t it_real_incr;
 431
 432        /* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
 433        cputime_t it_prof_expires, it_virt_expires;
 434        cputime_t it_prof_incr, it_virt_incr;
 435
 436        /* job control IDs */
 437
 438        /*
 439         * pgrp and session fields are deprecated.
 440         * use the task_session_Xnr and task_pgrp_Xnr routines below
 441         */
 442
 443        union {
 444                pid_t pgrp __deprecated;
 445                pid_t __pgrp;
 446        };
 447
 448        struct pid *tty_old_pgrp;
 449
 450        union {
 451                pid_t session __deprecated;
 452                pid_t __session;
 453        };
 454
 455        /* boolean value for session group leader */
 456        int leader;
 457
 458        struct tty_struct *tty; /* NULL if no tty */
 459
 460        /*
 461         * Cumulative resource counters for dead threads in the group,
 462         * and for reaped dead child processes forked by this group.
 463         * Live threads maintain their own counters and add to these
 464         * in __exit_signal, except for the group leader.
 465         */
 466        cputime_t utime, stime, cutime, cstime;
 467        cputime_t gtime;
 468        cputime_t cgtime;
 469        unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
 470        unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
 471        unsigned long inblock, oublock, cinblock, coublock;
 472
 473        /*
 474         * Cumulative ns of scheduled CPU time for dead threads in the
 475         * group, not including a zombie group leader.  (This only differs
 476         * from jiffies_to_ns(utime + stime) if sched_clock uses something
 477         * other than jiffies.)
 478         */
 479        unsigned long long sum_sched_runtime;
 480
 481        /*
 482         * We don't bother to synchronize most readers of this at all,
 483         * because there is no reader checking a limit that actually needs
 484         * to get both rlim_cur and rlim_max atomically, and either one
 485         * alone is a single word that can safely be read normally.
 486         * getrlimit/setrlimit use task_lock(current->group_leader) to
 487         * protect this instead of the siglock, because they really
 488         * have no need to disable irqs.
 489         */
 490        struct rlimit rlim[RLIM_NLIMITS];
 491
 492        struct list_head cpu_timers[3];
 493
 494        /* keep the process-shared keyrings here so that they do the right
 495         * thing in threads created with CLONE_THREAD */
 496#ifdef CONFIG_KEYS
 497        struct key *session_keyring;    /* keyring inherited over fork */
 498        struct key *process_keyring;    /* keyring private to this process */
 499#endif
 500#ifdef CONFIG_BSD_PROCESS_ACCT
 501        struct pacct_struct pacct;      /* per-process accounting information */
 502#endif
 503#ifdef CONFIG_TASKSTATS
 504        struct taskstats *stats;
 505#endif
 506#ifdef CONFIG_AUDIT
 507        unsigned audit_tty;
 508        struct tty_audit_buf *tty_audit_buf;
 509#endif
 510};
 511
 512/* Context switch must be unlocked if interrupts are to be enabled */
 513#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
 514# define __ARCH_WANT_UNLOCKED_CTXSW
 515#endif
 516
 517/*
 518 * Bits in flags field of signal_struct.
 519 */
 520#define SIGNAL_STOP_STOPPED     0x00000001 /* job control stop in effect */
 521#define SIGNAL_STOP_DEQUEUED    0x00000002 /* stop signal dequeued */
 522#define SIGNAL_STOP_CONTINUED   0x00000004 /* SIGCONT since WCONTINUED reap */
 523#define SIGNAL_GROUP_EXIT       0x00000008 /* group exit in progress */
 524
 525/*
 526 * Some day this will be a full-fledged user tracking system..
 527 */
 528struct user_struct {
 529        atomic_t __count;       /* reference count */
 530        atomic_t processes;     /* How many processes does this user have? */
 531        atomic_t files;         /* How many open files does this user have? */
 532        atomic_t sigpending;    /* How many pending signals does this user have? */
 533#ifdef CONFIG_INOTIFY_USER
 534        atomic_t inotify_watches; /* How many inotify watches does this user have? */
 535        atomic_t inotify_devs;  /* How many inotify devs does this user have opened? */
 536#endif
 537#ifdef CONFIG_POSIX_MQUEUE
 538        /* protected by mq_lock */
 539        unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
 540#endif
 541        unsigned long locked_shm; /* How many pages of mlocked shm ? */
 542
 543#ifdef CONFIG_KEYS
 544        struct key *uid_keyring;        /* UID specific keyring */
 545        struct key *session_keyring;    /* UID's default session keyring */
 546#endif
 547
 548        /* Hash table maintenance information */
 549        struct hlist_node uidhash_node;
 550        uid_t uid;
 551
 552#ifdef CONFIG_FAIR_USER_SCHED
 553        struct task_group *tg;
 554#ifdef CONFIG_SYSFS
 555        struct kset kset;
 556        struct subsys_attribute user_attr;
 557        struct work_struct work;
 558#endif
 559#endif
 560};
 561
 562#ifdef CONFIG_FAIR_USER_SCHED
 563extern int uids_kobject_init(void);
 564#else
 565static inline int uids_kobject_init(void) { return 0; }
 566#endif
 567
 568extern struct user_struct *find_user(uid_t);
 569
 570extern struct user_struct root_user;
 571#define INIT_USER (&root_user)
 572
 573struct backing_dev_info;
 574struct reclaim_state;
 575
 576#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
 577struct sched_info {
 578        /* cumulative counters */
 579        unsigned long pcount;         /* # of times run on this cpu */
 580        unsigned long long cpu_time,  /* time spent on the cpu */
 581                           run_delay; /* time spent waiting on a runqueue */
 582
 583        /* timestamps */
 584        unsigned long long last_arrival,/* when we last ran on a cpu */
 585                           last_queued; /* when we were last queued to run */
 586#ifdef CONFIG_SCHEDSTATS
 587        /* BKL stats */
 588        unsigned int bkl_count;
 589#endif
 590};
 591#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
 592
 593#ifdef CONFIG_SCHEDSTATS
 594extern const struct file_operations proc_schedstat_operations;
 595#endif /* CONFIG_SCHEDSTATS */
 596
 597#ifdef CONFIG_TASK_DELAY_ACCT
 598struct task_delay_info {
 599        spinlock_t      lock;
 600        unsigned int    flags;  /* Private per-task flags */
 601
 602        /* For each stat XXX, add following, aligned appropriately
 603         *
 604         * struct timespec XXX_start, XXX_end;
 605         * u64 XXX_delay;
 606         * u32 XXX_count;
 607         *
 608         * Atomicity of updates to XXX_delay, XXX_count protected by
 609         * single lock above (split into XXX_lock if contention is an issue).
 610         */
 611
 612        /*
 613         * XXX_count is incremented on every XXX operation, the delay
 614         * associated with the operation is added to XXX_delay.
 615         * XXX_delay contains the accumulated delay time in nanoseconds.
 616         */
 617        struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */
 618        u64 blkio_delay;        /* wait for sync block io completion */
 619        u64 swapin_delay;       /* wait for swapin block io completion */
 620        u32 blkio_count;        /* total count of the number of sync block */
 621                                /* io operations performed */
 622        u32 swapin_count;       /* total count of the number of swapin block */
 623                                /* io operations performed */
 624};
 625#endif  /* CONFIG_TASK_DELAY_ACCT */
 626
 627static inline int sched_info_on(void)
 628{
 629#ifdef CONFIG_SCHEDSTATS
 630        return 1;
 631#elif defined(CONFIG_TASK_DELAY_ACCT)
 632        extern int delayacct_on;
 633        return delayacct_on;
 634#else
 635        return 0;
 636#endif
 637}
 638
 639enum cpu_idle_type {
 640        CPU_IDLE,
 641        CPU_NOT_IDLE,
 642        CPU_NEWLY_IDLE,
 643        CPU_MAX_IDLE_TYPES
 644};
 645
 646/*
 647 * sched-domains (multiprocessor balancing) declarations:
 648 */
 649
 650/*
 651 * Increase resolution of nice-level calculations:
 652 */
 653#define SCHED_LOAD_SHIFT        10
 654#define SCHED_LOAD_SCALE        (1L << SCHED_LOAD_SHIFT)
 655
 656#define SCHED_LOAD_SCALE_FUZZ   SCHED_LOAD_SCALE
 657
 658#ifdef CONFIG_SMP
 659#define SD_LOAD_BALANCE         1       /* Do load balancing on this domain. */
 660#define SD_BALANCE_NEWIDLE      2       /* Balance when about to become idle */
 661#define SD_BALANCE_EXEC         4       /* Balance on exec */
 662#define SD_BALANCE_FORK         8       /* Balance on fork, clone */
 663#define SD_WAKE_IDLE            16      /* Wake to idle CPU on task wakeup */
 664#define SD_WAKE_AFFINE          32      /* Wake task to waking CPU */
 665#define SD_WAKE_BALANCE         64      /* Perform balancing at task wakeup */
 666#define SD_SHARE_CPUPOWER       128     /* Domain members share cpu power */
 667#define SD_POWERSAVINGS_BALANCE 256     /* Balance for power savings */
 668#define SD_SHARE_PKG_RESOURCES  512     /* Domain members share cpu pkg resources */
 669#define SD_SERIALIZE            1024    /* Only a single load balancing instance */
 670
 671#define BALANCE_FOR_MC_POWER    \
 672        (sched_smt_power_savings ? SD_POWERSAVINGS_BALANCE : 0)
 673
 674#define BALANCE_FOR_PKG_POWER   \
 675        ((sched_mc_power_savings || sched_smt_power_savings) ?  \
 676         SD_POWERSAVINGS_BALANCE : 0)
 677
 678#define test_sd_parent(sd, flag)        ((sd->parent &&         \
 679                                         (sd->parent->flags & flag)) ? 1 : 0)
 680
 681
 682struct sched_group {
 683        struct sched_group *next;       /* Must be a circular list */
 684        cpumask_t cpumask;
 685
 686        /*
 687         * CPU power of this group, SCHED_LOAD_SCALE being max power for a
 688         * single CPU. This is read only (except for setup, hotplug CPU).
 689         * Note : Never change cpu_power without recompute its reciprocal
 690         */
 691        unsigned int __cpu_power;
 692        /*
 693         * reciprocal value of cpu_power to avoid expensive divides
 694         * (see include/linux/reciprocal_div.h)
 695         */
 696        u32 reciprocal_cpu_power;
 697};
 698
 699struct sched_domain {
 700        /* These fields must be setup */
 701        struct sched_domain *parent;    /* top domain must be null terminated */
 702        struct sched_domain *child;     /* bottom domain must be null terminated */
 703        struct sched_group *groups;     /* the balancing groups of the domain */
 704        cpumask_t span;                 /* span of all CPUs in this domain */
 705        unsigned long min_interval;     /* Minimum balance interval ms */
 706        unsigned long max_interval;     /* Maximum balance interval ms */
 707        unsigned int busy_factor;       /* less balancing by factor if busy */
 708        unsigned int imbalance_pct;     /* No balance until over watermark */
 709        unsigned int cache_nice_tries;  /* Leave cache hot tasks for # tries */
 710        unsigned int busy_idx;
 711        unsigned int idle_idx;
 712        unsigned int newidle_idx;
 713        unsigned int wake_idx;
 714        unsigned int forkexec_idx;
 715        int flags;                      /* See SD_* */
 716
 717        /* Runtime fields. */
 718        unsigned long last_balance;     /* init to jiffies. units in jiffies */
 719        unsigned int balance_interval;  /* initialise to 1. units in ms. */
 720        unsigned int nr_balance_failed; /* initialise to 0 */
 721
 722#ifdef CONFIG_SCHEDSTATS
 723        /* load_balance() stats */
 724        unsigned int lb_count[CPU_MAX_IDLE_TYPES];
 725        unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
 726        unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
 727        unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
 728        unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
 729        unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
 730        unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
 731        unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
 732
 733        /* Active load balancing */
 734        unsigned int alb_count;
 735        unsigned int alb_failed;
 736        unsigned int alb_pushed;
 737
 738        /* SD_BALANCE_EXEC stats */
 739        unsigned int sbe_count;
 740        unsigned int sbe_balanced;
 741        unsigned int sbe_pushed;
 742
 743        /* SD_BALANCE_FORK stats */
 744        unsigned int sbf_count;
 745        unsigned int sbf_balanced;
 746        unsigned int sbf_pushed;
 747
 748        /* try_to_wake_up() stats */
 749        unsigned int ttwu_wake_remote;
 750        unsigned int ttwu_move_affine;
 751        unsigned int ttwu_move_balance;
 752#endif
 753};
 754
 755extern void partition_sched_domains(int ndoms_new, cpumask_t *doms_new);
 756
 757#endif  /* CONFIG_SMP */
 758
 759/*
 760 * A runqueue laden with a single nice 0 task scores a weighted_cpuload of
 761 * SCHED_LOAD_SCALE. This function returns 1 if any cpu is laden with a
 762 * task of nice 0 or enough lower priority tasks to bring up the
 763 * weighted_cpuload
 764 */
 765static inline int above_background_load(void)
 766{
 767        unsigned long cpu;
 768
 769        for_each_online_cpu(cpu) {
 770                if (weighted_cpuload(cpu) >= SCHED_LOAD_SCALE)
 771                        return 1;
 772        }
 773        return 0;
 774}
 775
 776struct io_context;                      /* See blkdev.h */
 777#define NGROUPS_SMALL           32
 778#define NGROUPS_PER_BLOCK       ((int)(PAGE_SIZE / sizeof(gid_t)))
 779struct group_info {
 780        int ngroups;
 781        atomic_t usage;
 782        gid_t small_block[NGROUPS_SMALL];
 783        int nblocks;
 784        gid_t *blocks[0];
 785};
 786
 787/*
 788 * get_group_info() must be called with the owning task locked (via task_lock())
 789 * when task != current.  The reason being that the vast majority of callers are
 790 * looking at current->group_info, which can not be changed except by the
 791 * current task.  Changing current->group_info requires the task lock, too.
 792 */
 793#define get_group_info(group_info) do { \
 794        atomic_inc(&(group_info)->usage); \
 795} while (0)
 796
 797#define put_group_info(group_info) do { \
 798        if (atomic_dec_and_test(&(group_info)->usage)) \
 799                groups_free(group_info); \
 800} while (0)
 801
 802extern struct group_info *groups_alloc(int gidsetsize);
 803extern void groups_free(struct group_info *group_info);
 804extern int set_current_groups(struct group_info *group_info);
 805extern int groups_search(struct group_info *group_info, gid_t grp);
 806/* access the groups "array" with this macro */
 807#define GROUP_AT(gi, i) \
 808    ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
 809
 810#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
 811extern void prefetch_stack(struct task_struct *t);
 812#else
 813static inline void prefetch_stack(struct task_struct *t) { }
 814#endif
 815
 816struct audit_context;           /* See audit.c */
 817struct mempolicy;
 818struct pipe_inode_info;
 819struct uts_namespace;
 820
 821struct rq;
 822struct sched_domain;
 823
 824struct sched_class {
 825        const struct sched_class *next;
 826
 827        void (*enqueue_task) (struct rq *rq, struct task_struct *p, int wakeup);
 828        void (*dequeue_task) (struct rq *rq, struct task_struct *p, int sleep);
 829        void (*yield_task) (struct rq *rq);
 830
 831        void (*check_preempt_curr) (struct rq *rq, struct task_struct *p);
 832
 833        struct task_struct * (*pick_next_task) (struct rq *rq);
 834        void (*put_prev_task) (struct rq *rq, struct task_struct *p);
 835
 836#ifdef CONFIG_SMP
 837        unsigned long (*load_balance) (struct rq *this_rq, int this_cpu,
 838                        struct rq *busiest, unsigned long max_load_move,
 839                        struct sched_domain *sd, enum cpu_idle_type idle,
 840                        int *all_pinned, int *this_best_prio);
 841
 842        int (*move_one_task) (struct rq *this_rq, int this_cpu,
 843                              struct rq *busiest, struct sched_domain *sd,
 844                              enum cpu_idle_type idle);
 845#endif
 846
 847        void (*set_curr_task) (struct rq *rq);
 848        void (*task_tick) (struct rq *rq, struct task_struct *p);
 849        void (*task_new) (struct rq *rq, struct task_struct *p);
 850};
 851
 852struct load_weight {
 853        unsigned long weight, inv_weight;
 854};
 855
 856/*
 857 * CFS stats for a schedulable entity (task, task-group etc)
 858 *
 859 * Current field usage histogram:
 860 *
 861 *     4 se->block_start
 862 *     4 se->run_node
 863 *     4 se->sleep_start
 864 *     6 se->load.weight
 865 */
 866struct sched_entity {
 867        struct load_weight      load;           /* for load-balancing */
 868        struct rb_node          run_node;
 869        unsigned int            on_rq;
 870
 871        u64                     exec_start;
 872        u64                     sum_exec_runtime;
 873        u64                     vruntime;
 874        u64                     prev_sum_exec_runtime;
 875
 876#ifdef CONFIG_SCHEDSTATS
 877        u64                     wait_start;
 878        u64                     wait_max;
 879
 880        u64                     sleep_start;
 881        u64                     sleep_max;
 882        s64                     sum_sleep_runtime;
 883
 884        u64                     block_start;
 885        u64                     block_max;
 886        u64                     exec_max;
 887        u64                     slice_max;
 888
 889        u64                     nr_migrations;
 890        u64                     nr_migrations_cold;
 891        u64                     nr_failed_migrations_affine;
 892        u64                     nr_failed_migrations_running;
 893        u64                     nr_failed_migrations_hot;
 894        u64                     nr_forced_migrations;
 895        u64                     nr_forced2_migrations;
 896
 897        u64                     nr_wakeups;
 898        u64                     nr_wakeups_sync;
 899        u64                     nr_wakeups_migrate;
 900        u64                     nr_wakeups_local;
 901        u64                     nr_wakeups_remote;
 902        u64                     nr_wakeups_affine;
 903        u64                     nr_wakeups_affine_attempts;
 904        u64                     nr_wakeups_passive;
 905        u64                     nr_wakeups_idle;
 906#endif
 907
 908#ifdef CONFIG_FAIR_GROUP_SCHED
 909        struct sched_entity     *parent;
 910        /* rq on which this entity is (to be) queued: */
 911        struct cfs_rq           *cfs_rq;
 912        /* rq "owned" by this entity/group: */
 913        struct cfs_rq           *my_q;
 914#endif
 915};
 916
 917struct task_struct {
 918        volatile long state;    /* -1 unrunnable, 0 runnable, >0 stopped */
 919        void *stack;
 920        atomic_t usage;
 921        unsigned int flags;     /* per process flags, defined below */
 922        unsigned int ptrace;
 923
 924        int lock_depth;         /* BKL lock depth */
 925
 926#ifdef CONFIG_SMP
 927#ifdef __ARCH_WANT_UNLOCKED_CTXSW
 928        int oncpu;
 929#endif
 930#endif
 931
 932        int prio, static_prio, normal_prio;
 933        struct list_head run_list;
 934        const struct sched_class *sched_class;
 935        struct sched_entity se;
 936
 937#ifdef CONFIG_PREEMPT_NOTIFIERS
 938        /* list of struct preempt_notifier: */
 939        struct hlist_head preempt_notifiers;
 940#endif
 941
 942        unsigned short ioprio;
 943        /*
 944         * fpu_counter contains the number of consecutive context switches
 945         * that the FPU is used. If this is over a threshold, the lazy fpu
 946         * saving becomes unlazy to save the trap. This is an unsigned char
 947         * so that after 256 times the counter wraps and the behavior turns
 948         * lazy again; this to deal with bursty apps that only use FPU for
 949         * a short time
 950         */
 951        unsigned char fpu_counter;
 952        s8 oomkilladj; /* OOM kill score adjustment (bit shift). */
 953#ifdef CONFIG_BLK_DEV_IO_TRACE
 954        unsigned int btrace_seq;
 955#endif
 956
 957        unsigned int policy;
 958        cpumask_t cpus_allowed;
 959        unsigned int time_slice;
 960
 961#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
 962        struct sched_info sched_info;
 963#endif
 964
 965        struct list_head tasks;
 966        /*
 967         * ptrace_list/ptrace_children forms the list of my children
 968         * that were stolen by a ptracer.
 969         */
 970        struct list_head ptrace_children;
 971        struct list_head ptrace_list;
 972
 973        struct mm_struct *mm, *active_mm;
 974
 975/* task state */
 976        struct linux_binfmt *binfmt;
 977        int exit_state;
 978        int exit_code, exit_signal;
 979        int pdeath_signal;  /*  The signal sent when the parent dies  */
 980        /* ??? */
 981        unsigned int personality;
 982        unsigned did_exec:1;
 983        pid_t pid;
 984        pid_t tgid;
 985
 986#ifdef CONFIG_CC_STACKPROTECTOR
 987        /* Canary value for the -fstack-protector gcc feature */
 988        unsigned long stack_canary;
 989#endif
 990        /* 
 991         * pointers to (original) parent process, youngest child, younger sibling,
 992         * older sibling, respectively.  (p->father can be replaced with 
 993         * p->parent->pid)
 994         */
 995        struct task_struct *real_parent; /* real parent process (when being debugged) */
 996        struct task_struct *parent;     /* parent process */
 997        /*
 998         * children/sibling forms the list of my children plus the
 999         * tasks I'm ptracing.
1000         */
1001        struct list_head children;      /* list of my children */
1002        struct list_head sibling;       /* linkage in my parent's children list */
1003        struct task_struct *group_leader;       /* threadgroup leader */
1004
1005        /* PID/PID hash table linkage. */
1006        struct pid_link pids[PIDTYPE_MAX];
1007        struct list_head thread_group;
1008
1009        struct completion *vfork_done;          /* for vfork() */
1010        int __user *set_child_tid;              /* CLONE_CHILD_SETTID */
1011        int __user *clear_child_tid;            /* CLONE_CHILD_CLEARTID */
1012
1013        unsigned int rt_priority;
1014        cputime_t utime, stime, utimescaled, stimescaled;
1015        cputime_t gtime;
1016        cputime_t prev_utime, prev_stime;
1017        unsigned long nvcsw, nivcsw; /* context switch counts */
1018        struct timespec start_time;             /* monotonic time */
1019        struct timespec real_start_time;        /* boot based time */
1020/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1021        unsigned long min_flt, maj_flt;
1022
1023        cputime_t it_prof_expires, it_virt_expires;
1024        unsigned long long it_sched_expires;
1025        struct list_head cpu_timers[3];
1026
1027/* process credentials */
1028        uid_t uid,euid,suid,fsuid;
1029        gid_t gid,egid,sgid,fsgid;
1030        struct group_info *group_info;
1031        kernel_cap_t   cap_effective, cap_inheritable, cap_permitted;
1032        unsigned keep_capabilities:1;
1033        struct user_struct *user;
1034#ifdef CONFIG_KEYS
1035        struct key *request_key_auth;   /* assumed request_key authority */
1036        struct key *thread_keyring;     /* keyring private to this thread */
1037        unsigned char jit_keyring;      /* default keyring to attach requested keys to */
1038#endif
1039        char comm[TASK_COMM_LEN]; /* executable name excluding path
1040                                     - access with [gs]et_task_comm (which lock
1041                                       it with task_lock())
1042                                     - initialized normally by flush_old_exec */
1043/* file system info */
1044        int link_count, total_link_count;
1045#ifdef CONFIG_SYSVIPC
1046/* ipc stuff */
1047        struct sysv_sem sysvsem;
1048#endif
1049/* CPU-specific state of this task */
1050        struct thread_struct thread;
1051/* filesystem information */
1052        struct fs_struct *fs;
1053/* open file information */
1054        struct files_struct *files;
1055/* namespaces */
1056        struct nsproxy *nsproxy;
1057/* signal handlers */
1058        struct signal_struct *signal;
1059        struct sighand_struct *sighand;
1060
1061        sigset_t blocked, real_blocked;
1062        sigset_t saved_sigmask;         /* To be restored with TIF_RESTORE_SIGMASK */
1063        struct sigpending pending;
1064
1065        unsigned long sas_ss_sp;
1066        size_t sas_ss_size;
1067        int (*notifier)(void *priv);
1068        void *notifier_data;
1069        sigset_t *notifier_mask;
1070#ifdef CONFIG_SECURITY
1071        void *security;
1072#endif
1073        struct audit_context *audit_context;
1074        seccomp_t seccomp;
1075
1076/* Thread group tracking */
1077        u32 parent_exec_id;
1078        u32 self_exec_id;
1079/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
1080        spinlock_t alloc_lock;
1081
1082        /* Protection of the PI data structures: */
1083        spinlock_t pi_lock;
1084
1085#ifdef CONFIG_RT_MUTEXES
1086        /* PI waiters blocked on a rt_mutex held by this task */
1087        struct plist_head pi_waiters;
1088        /* Deadlock detection and priority inheritance handling */
1089        struct rt_mutex_waiter *pi_blocked_on;
1090#endif
1091
1092#ifdef CONFIG_DEBUG_MUTEXES
1093        /* mutex deadlock detection */
1094        struct mutex_waiter *blocked_on;
1095#endif
1096#ifdef CONFIG_TRACE_IRQFLAGS
1097        unsigned int irq_events;
1098        int hardirqs_enabled;
1099        unsigned long hardirq_enable_ip;
1100        unsigned int hardirq_enable_event;
1101        unsigned long hardirq_disable_ip;
1102        unsigned int hardirq_disable_event;
1103        int softirqs_enabled;
1104        unsigned long softirq_disable_ip;
1105        unsigned int softirq_disable_event;
1106        unsigned long softirq_enable_ip;
1107        unsigned int softirq_enable_event;
1108        int hardirq_context;
1109        int softirq_context;
1110#endif
1111#ifdef CONFIG_LOCKDEP
1112# define MAX_LOCK_DEPTH 30UL
1113        u64 curr_chain_key;
1114        int lockdep_depth;
1115        struct held_lock held_locks[MAX_LOCK_DEPTH];
1116        unsigned int lockdep_recursion;
1117#endif
1118
1119/* journalling filesystem info */
1120        void *journal_info;
1121
1122/* stacked block device info */
1123        struct bio *bio_list, **bio_tail;
1124
1125/* VM state */
1126        struct reclaim_state *reclaim_state;
1127
1128        struct backing_dev_info *backing_dev_info;
1129
1130        struct io_context *io_context;
1131
1132        unsigned long ptrace_message;
1133        siginfo_t *last_siginfo; /* For ptrace use.  */
1134#ifdef CONFIG_TASK_XACCT
1135/* i/o counters(bytes read/written, #syscalls */
1136        u64 rchar, wchar, syscr, syscw;
1137#endif
1138        struct task_io_accounting ioac;
1139#if defined(CONFIG_TASK_XACCT)
1140        u64 acct_rss_mem1;      /* accumulated rss usage */
1141        u64 acct_vm_mem1;       /* accumulated virtual memory usage */
1142        cputime_t acct_stimexpd;/* stime since last update */
1143#endif
1144#ifdef CONFIG_NUMA
1145        struct mempolicy *mempolicy;
1146        short il_next;
1147#endif
1148#ifdef CONFIG_CPUSETS
1149        nodemask_t mems_allowed;
1150        int cpuset_mems_generation;
1151        int cpuset_mem_spread_rotor;
1152#endif
1153#ifdef CONFIG_CGROUPS
1154        /* Control Group info protected by css_set_lock */
1155        struct css_set *cgroups;
1156        /* cg_list protected by css_set_lock and tsk->alloc_lock */
1157        struct list_head cg_list;
1158#endif
1159#ifdef CONFIG_FUTEX
1160        struct robust_list_head __user *robust_list;
1161#ifdef CONFIG_COMPAT
1162        struct compat_robust_list_head __user *compat_robust_list;
1163#endif
1164        struct list_head pi_state_list;
1165        struct futex_pi_state *pi_state_cache;
1166#endif
1167        atomic_t fs_excl;       /* holding fs exclusive resources */
1168        struct rcu_head rcu;
1169
1170        /*
1171         * cache last used pipe for splice
1172         */
1173        struct pipe_inode_info *splice_pipe;
1174#ifdef  CONFIG_TASK_DELAY_ACCT
1175        struct task_delay_info *delays;
1176#endif
1177#ifdef CONFIG_FAULT_INJECTION
1178        int make_it_fail;
1179#endif
1180        struct prop_local_single dirties;
1181};
1182
1183/*
1184 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1185 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1186 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1187 * values are inverted: lower p->prio value means higher priority.
1188 *
1189 * The MAX_USER_RT_PRIO value allows the actual maximum
1190 * RT priority to be separate from the value exported to
1191 * user-space.  This allows kernel threads to set their
1192 * priority to a value higher than any user task. Note:
1193 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1194 */
1195
1196#define MAX_USER_RT_PRIO        100
1197#define MAX_RT_PRIO             MAX_USER_RT_PRIO
1198
1199#define MAX_PRIO                (MAX_RT_PRIO + 40)
1200#define DEFAULT_PRIO            (MAX_RT_PRIO + 20)
1201
1202static inline int rt_prio(int prio)
1203{
1204        if (unlikely(prio < MAX_RT_PRIO))
1205                return 1;
1206        return 0;
1207}
1208
1209static inline int rt_task(struct task_struct *p)
1210{
1211        return rt_prio(p->prio);
1212}
1213
1214static inline void set_task_session(struct task_struct *tsk, pid_t session)
1215{
1216        tsk->signal->__session = session;
1217}
1218
1219static inline void set_task_pgrp(struct task_struct *tsk, pid_t pgrp)
1220{
1221        tsk->signal->__pgrp = pgrp;
1222}
1223
1224static inline struct pid *task_pid(struct task_struct *task)
1225{
1226        return task->pids[PIDTYPE_PID].pid;
1227}
1228
1229static inline struct pid *task_tgid(struct task_struct *task)
1230{
1231        return task->group_leader->pids[PIDTYPE_PID].pid;
1232}
1233
1234static inline struct pid *task_pgrp(struct task_struct *task)
1235{
1236        return task->group_leader->pids[PIDTYPE_PGID].pid;
1237}
1238
1239static inline struct pid *task_session(struct task_struct *task)
1240{
1241        return task->group_leader->pids[PIDTYPE_SID].pid;
1242}
1243
1244struct pid_namespace;
1245
1246/*
1247 * the helpers to get the task's different pids as they are seen
1248 * from various namespaces
1249 *
1250 * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1251 * task_xid_vnr()    : virtual id, i.e. the id seen from the namespace the task
1252 *                     belongs to. this only makes sence when called in the
1253 *                     context of the task that belongs to the same namespace;
1254 * task_xid_nr_ns()  : id seen from the ns specified;
1255 *
1256 * set_task_vxid()   : assigns a virtual id to a task;
1257 *
1258 * see also pid_nr() etc in include/linux/pid.h
1259 */
1260
1261static inline pid_t task_pid_nr(struct task_struct *tsk)
1262{
1263        return tsk->pid;
1264}
1265
1266pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1267
1268static inline pid_t task_pid_vnr(struct task_struct *tsk)
1269{
1270        return pid_vnr(task_pid(tsk));
1271}
1272
1273
1274static inline pid_t task_tgid_nr(struct task_struct *tsk)
1275{
1276        return tsk->tgid;
1277}
1278
1279pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1280
1281static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1282{
1283        return pid_vnr(task_tgid(tsk));
1284}
1285
1286
1287static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1288{
1289        return tsk->signal->__pgrp;
1290}
1291
1292pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1293
1294static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1295{
1296        return pid_vnr(task_pgrp(tsk));
1297}
1298
1299
1300static inline pid_t task_session_nr(struct task_struct *tsk)
1301{
1302        return tsk->signal->__session;
1303}
1304
1305pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1306
1307static inline pid_t task_session_vnr(struct task_struct *tsk)
1308{
1309        return pid_vnr(task_session(tsk));
1310}
1311
1312
1313/**
1314 * pid_alive - check that a task structure is not stale
1315 * @p: Task structure to be checked.
1316 *
1317 * Test if a process is not yet dead (at most zombie state)
1318 * If pid_alive fails, then pointers within the task structure
1319 * can be stale and must not be dereferenced.
1320 */
1321static inline int pid_alive(struct task_struct *p)
1322{
1323        return p->pids[PIDTYPE_PID].pid != NULL;
1324}
1325
1326/**
1327 * is_global_init - check if a task structure is init
1328 * @tsk: Task structure to be checked.
1329 *
1330 * Check if a task structure is the first user space task the kernel created.
1331 */
1332static inline int is_global_init(struct task_struct *tsk)
1333{
1334        return tsk->pid == 1;
1335}
1336
1337/*
1338 * is_container_init:
1339 * check whether in the task is init in its own pid namespace.
1340 */
1341extern int is_container_init(struct task_struct *tsk);
1342
1343extern struct pid *cad_pid;
1344
1345extern void free_task(struct task_struct *tsk);
1346#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1347
1348extern void __put_task_struct(struct task_struct *t);
1349
1350static inline void put_task_struct(struct task_struct *t)
1351{
1352        if (atomic_dec_and_test(&t->usage))
1353                __put_task_struct(t);
1354}
1355
1356/*
1357 * Per process flags
1358 */
1359#define PF_ALIGNWARN    0x00000001      /* Print alignment warning msgs */
1360                                        /* Not implemented yet, only for 486*/
1361#define PF_STARTING     0x00000002      /* being created */
1362#define PF_EXITING      0x00000004      /* getting shut down */
1363#define PF_EXITPIDONE   0x00000008      /* pi exit done on shut down */
1364#define PF_VCPU         0x00000010      /* I'm a virtual CPU */
1365#define PF_FORKNOEXEC   0x00000040      /* forked but didn't exec */
1366#define PF_SUPERPRIV    0x00000100      /* used super-user privileges */
1367#define PF_DUMPCORE     0x00000200      /* dumped core */
1368#define PF_SIGNALED     0x00000400      /* killed by a signal */
1369#define PF_MEMALLOC     0x00000800      /* Allocating memory */
1370#define PF_FLUSHER      0x00001000      /* responsible for disk writeback */
1371#define PF_USED_MATH    0x00002000      /* if unset the fpu must be initialized before use */
1372#define PF_NOFREEZE     0x00008000      /* this thread should not be frozen */
1373#define PF_FROZEN       0x00010000      /* frozen for system suspend */
1374#define PF_FSTRANS      0x00020000      /* inside a filesystem transaction */
1375#define PF_KSWAPD       0x00040000      /* I am kswapd */
1376#define PF_SWAPOFF      0x00080000      /* I am in swapoff */
1377#define PF_LESS_THROTTLE 0x00100000     /* Throttle me less: I clean memory */
1378#define PF_BORROWED_MM  0x00200000      /* I am a kthread doing use_mm */
1379#define PF_RANDOMIZE    0x00400000      /* randomize virtual address space */
1380#define PF_SWAPWRITE    0x00800000      /* Allowed to write to swap */
1381#define PF_SPREAD_PAGE  0x01000000      /* Spread page cache over cpuset */
1382#define PF_SPREAD_SLAB  0x02000000      /* Spread some slab caches over cpuset */
1383#define PF_MEMPOLICY    0x10000000      /* Non-default NUMA mempolicy */
1384#define PF_MUTEX_TESTER 0x20000000      /* Thread belongs to the rt mutex tester */
1385#define PF_FREEZER_SKIP 0x40000000      /* Freezer should not count it as freezeable */
1386
1387/*
1388 * Only the _current_ task can read/write to tsk->flags, but other
1389 * tasks can access tsk->flags in readonly mode for example
1390 * with tsk_used_math (like during threaded core dumping).
1391 * There is however an exception to this rule during ptrace
1392 * or during fork: the ptracer task is allowed to write to the
1393 * child->flags of its traced child (same goes for fork, the parent
1394 * can write to the child->flags), because we're guaranteed the
1395 * child is not running and in turn not changing child->flags
1396 * at the same time the parent does it.
1397 */
1398#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1399#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1400#define clear_used_math() clear_stopped_child_used_math(current)
1401#define set_used_math() set_stopped_child_used_math(current)
1402#define conditional_stopped_child_used_math(condition, child) \
1403        do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1404#define conditional_used_math(condition) \
1405        conditional_stopped_child_used_math(condition, current)
1406#define copy_to_stopped_child_used_math(child) \
1407        do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1408/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1409#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1410#define used_math() tsk_used_math(current)
1411
1412#ifdef CONFIG_SMP
1413extern int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask);
1414#else
1415static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1416{
1417        if (!cpu_isset(0, new_mask))
1418                return -EINVAL;
1419        return 0;
1420}
1421#endif
1422
1423extern unsigned long long sched_clock(void);
1424
1425/*
1426 * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
1427 * clock constructed from sched_clock():
1428 */
1429extern unsigned long long cpu_clock(int cpu);
1430
1431extern unsigned long long
1432task_sched_runtime(struct task_struct *task);
1433
1434/* sched_exec is called by processes performing an exec */
1435#ifdef CONFIG_SMP
1436extern void sched_exec(void);
1437#else
1438#define sched_exec()   {}
1439#endif
1440
1441extern void sched_clock_idle_sleep_event(void);
1442extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1443
1444#ifdef CONFIG_HOTPLUG_CPU
1445extern void idle_task_exit(void);
1446#else
1447static inline void idle_task_exit(void) {}
1448#endif
1449
1450extern void sched_idle_next(void);
1451
1452#ifdef CONFIG_SCHED_DEBUG
1453extern unsigned int sysctl_sched_latency;
1454extern unsigned int sysctl_sched_min_granularity;
1455extern unsigned int sysctl_sched_wakeup_granularity;
1456extern unsigned int sysctl_sched_batch_wakeup_granularity;
1457extern unsigned int sysctl_sched_child_runs_first;
1458extern unsigned int sysctl_sched_features;
1459extern unsigned int sysctl_sched_migration_cost;
1460extern unsigned int sysctl_sched_nr_migrate;
1461
1462int sched_nr_latency_handler(struct ctl_table *table, int write,
1463                struct file *file, void __user *buffer, size_t *length,
1464                loff_t *ppos);
1465#endif
1466
1467extern unsigned int sysctl_sched_compat_yield;
1468
1469#ifdef CONFIG_RT_MUTEXES
1470extern int rt_mutex_getprio(struct task_struct *p);
1471extern void rt_mutex_setprio(struct task_struct *p, int prio);
1472extern void rt_mutex_adjust_pi(struct task_struct *p);
1473#else
1474static inline int rt_mutex_getprio(struct task_struct *p)
1475{
1476        return p->normal_prio;
1477}
1478# define rt_mutex_adjust_pi(p)          do { } while (0)
1479#endif
1480
1481extern void set_user_nice(struct task_struct *p, long nice);
1482extern int task_prio(const struct task_struct *p);
1483extern int task_nice(const struct task_struct *p);
1484extern int can_nice(const struct task_struct *p, const int nice);
1485extern int task_curr(const struct task_struct *p);
1486extern int idle_cpu(int cpu);
1487extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1488extern struct task_struct *idle_task(int cpu);
1489extern struct task_struct *curr_task(int cpu);
1490extern void set_curr_task(int cpu, struct task_struct *p);
1491
1492void yield(void);
1493
1494/*
1495 * The default (Linux) execution domain.
1496 */
1497extern struct exec_domain       default_exec_domain;
1498
1499union thread_union {
1500        struct thread_info thread_info;
1501        unsigned long stack[THREAD_SIZE/sizeof(long)];
1502};
1503
1504#ifndef __HAVE_ARCH_KSTACK_END
1505static inline int kstack_end(void *addr)
1506{
1507        /* Reliable end of stack detection:
1508         * Some APM bios versions misalign the stack
1509         */
1510        return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1511}
1512#endif
1513
1514extern union thread_union init_thread_union;
1515extern struct task_struct init_task;
1516
1517extern struct   mm_struct init_mm;
1518
1519extern struct pid_namespace init_pid_ns;
1520
1521/*
1522 * find a task by one of its numerical ids
1523 *
1524 * find_task_by_pid_type_ns():
1525 *      it is the most generic call - it finds a task by all id,
1526 *      type and namespace specified
1527 * find_task_by_pid_ns():
1528 *      finds a task by its pid in the specified namespace
1529 * find_task_by_vpid():
1530 *      finds a task by its virtual pid
1531 * find_task_by_pid():
1532 *      finds a task by its global pid
1533 *
1534 * see also find_pid() etc in include/linux/pid.h
1535 */
1536
1537extern struct task_struct *find_task_by_pid_type_ns(int type, int pid,
1538                struct pid_namespace *ns);
1539
1540extern struct task_struct *find_task_by_pid(pid_t nr);
1541extern struct task_struct *find_task_by_vpid(pid_t nr);
1542extern struct task_struct *find_task_by_pid_ns(pid_t nr,
1543                struct pid_namespace *ns);
1544
1545extern void __set_special_pids(pid_t session, pid_t pgrp);
1546
1547/* per-UID process charging. */
1548extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
1549static inline struct user_struct *get_uid(struct user_struct *u)
1550{
1551        atomic_inc(&u->__count);
1552        return u;
1553}
1554extern void free_uid(struct user_struct *);
1555extern void switch_uid(struct user_struct *);
1556extern void release_uids(struct user_namespace *ns);
1557
1558#include <asm/current.h>
1559
1560extern void do_timer(unsigned long ticks);
1561
1562extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state));
1563extern int FASTCALL(wake_up_process(struct task_struct * tsk));
1564extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
1565                                                unsigned long clone_flags));
1566#ifdef CONFIG_SMP
1567 extern void kick_process(struct task_struct *tsk);
1568#else
1569 static inline void kick_process(struct task_struct *tsk) { }
1570#endif
1571extern void sched_fork(struct task_struct *p, int clone_flags);
1572extern void sched_dead(struct task_struct *p);
1573
1574extern int in_group_p(gid_t);
1575extern int in_egroup_p(gid_t);
1576
1577extern void proc_caches_init(void);
1578extern void flush_signals(struct task_struct *);
1579extern void ignore_signals(struct task_struct *);
1580extern void flush_signal_handlers(struct task_struct *, int force_default);
1581extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1582
1583static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1584{
1585        unsigned long flags;
1586        int ret;
1587
1588        spin_lock_irqsave(&tsk->sighand->siglock, flags);
1589        ret = dequeue_signal(tsk, mask, info);
1590        spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1591
1592        return ret;
1593}       
1594
1595extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1596                              sigset_t *mask);
1597extern void unblock_all_signals(void);
1598extern void release_task(struct task_struct * p);
1599extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1600extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
1601extern int force_sigsegv(int, struct task_struct *);
1602extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1603extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1604extern int kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1605extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
1606extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
1607extern int kill_pgrp(struct pid *pid, int sig, int priv);
1608extern int kill_pid(struct pid *pid, int sig, int priv);
1609extern int kill_proc_info(int, struct siginfo *, pid_t);
1610extern void do_notify_parent(struct task_struct *, int);
1611extern void force_sig(int, struct task_struct *);
1612extern void force_sig_specific(int, struct task_struct *);
1613extern int send_sig(int, struct task_struct *, int);
1614extern void zap_other_threads(struct task_struct *p);
1615extern int kill_proc(pid_t, int, int);
1616extern struct sigqueue *sigqueue_alloc(void);
1617extern void sigqueue_free(struct sigqueue *);
1618extern int send_sigqueue(int, struct sigqueue *,  struct task_struct *);
1619extern int send_group_sigqueue(int, struct sigqueue *,  struct task_struct *);
1620extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
1621extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1622
1623static inline int kill_cad_pid(int sig, int priv)
1624{
1625        return kill_pid(cad_pid, sig, priv);
1626}
1627
1628/* These can be the second arg to send_sig_info/send_group_sig_info.  */
1629#define SEND_SIG_NOINFO ((struct siginfo *) 0)
1630#define SEND_SIG_PRIV   ((struct siginfo *) 1)
1631#define SEND_SIG_FORCED ((struct siginfo *) 2)
1632
1633static inline int is_si_special(const struct siginfo *info)
1634{
1635        return info <= SEND_SIG_FORCED;
1636}
1637
1638/* True if we are on the alternate signal stack.  */
1639
1640static inline int on_sig_stack(unsigned long sp)
1641{
1642        return (sp - current->sas_ss_sp < current->sas_ss_size);
1643}
1644
1645static inline int sas_ss_flags(unsigned long sp)
1646{
1647        return (current->sas_ss_size == 0 ? SS_DISABLE
1648                : on_sig_stack(sp) ? SS_ONSTACK : 0);
1649}
1650
1651/*
1652 * Routines for handling mm_structs
1653 */
1654extern struct mm_struct * mm_alloc(void);
1655
1656/* mmdrop drops the mm and the page tables */
1657extern void FASTCALL(__mmdrop(struct mm_struct *));
1658static inline void mmdrop(struct mm_struct * mm)
1659{
1660        if (unlikely(atomic_dec_and_test(&mm->mm_count)))
1661                __mmdrop(mm);
1662}
1663
1664/* mmput gets rid of the mappings and all user-space */
1665extern void mmput(struct mm_struct *);
1666/* Grab a reference to a task's mm, if it is not already going away */
1667extern struct mm_struct *get_task_mm(struct task_struct *task);
1668/* Remove the current tasks stale references to the old mm_struct */
1669extern void mm_release(struct task_struct *, struct mm_struct *);
1670
1671extern int  copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1672extern void flush_thread(void);
1673extern void exit_thread(void);
1674
1675extern void exit_files(struct task_struct *);
1676extern void __cleanup_signal(struct signal_struct *);
1677extern void __cleanup_sighand(struct sighand_struct *);
1678extern void exit_itimers(struct signal_struct *);
1679
1680extern NORET_TYPE void do_group_exit(int);
1681
1682extern void daemonize(const char *, ...);
1683extern int allow_signal(int);
1684extern int disallow_signal(int);
1685
1686extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1687extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1688struct task_struct *fork_idle(int);
1689
1690extern void set_task_comm(struct task_struct *tsk, char *from);
1691extern void get_task_comm(char *to, struct task_struct *tsk);
1692
1693#ifdef CONFIG_SMP
1694extern void wait_task_inactive(struct task_struct * p);
1695#else
1696#define wait_task_inactive(p)   do { } while (0)
1697#endif
1698
1699#define remove_parent(p)        list_del_init(&(p)->sibling)
1700#define add_parent(p)           list_add_tail(&(p)->sibling,&(p)->parent->children)
1701
1702#define next_task(p)    list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
1703
1704#define for_each_process(p) \
1705        for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1706
1707/*
1708 * Careful: do_each_thread/while_each_thread is a double loop so
1709 *          'break' will not work as expected - use goto instead.
1710 */
1711#define do_each_thread(g, t) \
1712        for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1713
1714#define while_each_thread(g, t) \
1715        while ((t = next_thread(t)) != g)
1716
1717/* de_thread depends on thread_group_leader not being a pid based check */
1718#define thread_group_leader(p)  (p == p->group_leader)
1719
1720/* Do to the insanities of de_thread it is possible for a process
1721 * to have the pid of the thread group leader without actually being
1722 * the thread group leader.  For iteration through the pids in proc
1723 * all we care about is that we have a task with the appropriate
1724 * pid, we don't actually care if we have the right task.
1725 */
1726static inline int has_group_leader_pid(struct task_struct *p)
1727{
1728        return p->pid == p->tgid;
1729}
1730
1731static inline
1732int same_thread_group(struct task_struct *p1, struct task_struct *p2)
1733{
1734        return p1->tgid == p2->tgid;
1735}
1736
1737static inline struct task_struct *next_thread(const struct task_struct *p)
1738{
1739        return list_entry(rcu_dereference(p->thread_group.next),
1740                          struct task_struct, thread_group);
1741}
1742
1743static inline int thread_group_empty(struct task_struct *p)
1744{
1745        return list_empty(&p->thread_group);
1746}
1747
1748#define delay_group_leader(p) \
1749                (thread_group_leader(p) && !thread_group_empty(p))
1750
1751/*
1752 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
1753 * subscriptions and synchronises with wait4().  Also used in procfs.  Also
1754 * pins the final release of task.io_context.  Also protects ->cpuset and
1755 * ->cgroup.subsys[].
1756 *
1757 * Nests both inside and outside of read_lock(&tasklist_lock).
1758 * It must not be nested with write_lock_irq(&tasklist_lock),
1759 * neither inside nor outside.
1760 */
1761static inline void task_lock(struct task_struct *p)
1762{
1763        spin_lock(&p->alloc_lock);
1764}
1765
1766static inline void task_unlock(struct task_struct *p)
1767{
1768        spin_unlock(&p->alloc_lock);
1769}
1770
1771extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
1772                                                        unsigned long *flags);
1773
1774static inline void unlock_task_sighand(struct task_struct *tsk,
1775                                                unsigned long *flags)
1776{
1777        spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
1778}
1779
1780#ifndef __HAVE_THREAD_FUNCTIONS
1781
1782#define task_thread_info(task)  ((struct thread_info *)(task)->stack)
1783#define task_stack_page(task)   ((task)->stack)
1784
1785static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
1786{
1787        *task_thread_info(p) = *task_thread_info(org);
1788        task_thread_info(p)->task = p;
1789}
1790
1791static inline unsigned long *end_of_stack(struct task_struct *p)
1792{
1793        return (unsigned long *)(task_thread_info(p) + 1);
1794}
1795
1796#endif
1797
1798/* set thread flags in other task's structures
1799 * - see asm/thread_info.h for TIF_xxxx flags available
1800 */
1801static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1802{
1803        set_ti_thread_flag(task_thread_info(tsk), flag);
1804}
1805
1806static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1807{
1808        clear_ti_thread_flag(task_thread_info(tsk), flag);
1809}
1810
1811static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1812{
1813        return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1814}
1815
1816static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1817{
1818        return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1819}
1820
1821static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1822{
1823        return test_ti_thread_flag(task_thread_info(tsk), flag);
1824}
1825
1826static inline void set_tsk_need_resched(struct task_struct *tsk)
1827{
1828        set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1829}
1830
1831static inline void clear_tsk_need_resched(struct task_struct *tsk)
1832{
1833        clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1834}
1835
1836static inline int signal_pending(struct task_struct *p)
1837{
1838        return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1839}
1840  
1841static inline int need_resched(void)
1842{
1843        return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1844}
1845
1846/*
1847 * cond_resched() and cond_resched_lock(): latency reduction via
1848 * explicit rescheduling in places that are safe. The return
1849 * value indicates whether a reschedule was done in fact.
1850 * cond_resched_lock() will drop the spinlock before scheduling,
1851 * cond_resched_softirq() will enable bhs before scheduling.
1852 */
1853extern int cond_resched(void);
1854extern int cond_resched_lock(spinlock_t * lock);
1855extern int cond_resched_softirq(void);
1856
1857/*
1858 * Does a critical section need to be broken due to another
1859 * task waiting?:
1860 */
1861#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
1862# define need_lockbreak(lock) ((lock)->break_lock)
1863#else
1864# define need_lockbreak(lock) 0
1865#endif
1866
1867/*
1868 * Does a critical section need to be broken due to another
1869 * task waiting or preemption being signalled:
1870 */
1871static inline int lock_need_resched(spinlock_t *lock)
1872{
1873        if (need_lockbreak(lock) || need_resched())
1874                return 1;
1875        return 0;
1876}
1877
1878/*
1879 * Reevaluate whether the task has signals pending delivery.
1880 * Wake the task if so.
1881 * This is required every time the blocked sigset_t changes.
1882 * callers must hold sighand->siglock.
1883 */
1884extern void recalc_sigpending_and_wake(struct task_struct *t);
1885extern void recalc_sigpending(void);
1886
1887extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1888
1889/*
1890 * Wrappers for p->thread_info->cpu access. No-op on UP.
1891 */
1892#ifdef CONFIG_SMP
1893
1894static inline unsigned int task_cpu(const struct task_struct *p)
1895{
1896        return task_thread_info(p)->cpu;
1897}
1898
1899extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
1900
1901#else
1902
1903static inline unsigned int task_cpu(const struct task_struct *p)
1904{
1905        return 0;
1906}
1907
1908static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1909{
1910}
1911
1912#endif /* CONFIG_SMP */
1913
1914#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1915extern void arch_pick_mmap_layout(struct mm_struct *mm);
1916#else
1917static inline void arch_pick_mmap_layout(struct mm_struct *mm)
1918{
1919        mm->mmap_base = TASK_UNMAPPED_BASE;
1920        mm->get_unmapped_area = arch_get_unmapped_area;
1921        mm->unmap_area = arch_unmap_area;
1922}
1923#endif
1924
1925extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
1926extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
1927
1928extern int sched_mc_power_savings, sched_smt_power_savings;
1929
1930extern void normalize_rt_tasks(void);
1931
1932#ifdef CONFIG_FAIR_GROUP_SCHED
1933
1934extern struct task_group init_task_group;
1935
1936extern struct task_group *sched_create_group(void);
1937extern void sched_destroy_group(struct task_group *tg);
1938extern void sched_move_task(struct task_struct *tsk);
1939extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
1940extern unsigned long sched_group_shares(struct task_group *tg);
1941
1942#endif
1943
1944#ifdef CONFIG_TASK_XACCT
1945static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
1946{
1947        tsk->rchar += amt;
1948}
1949
1950static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
1951{
1952        tsk->wchar += amt;
1953}
1954
1955static inline void inc_syscr(struct task_struct *tsk)
1956{
1957        tsk->syscr++;
1958}
1959
1960static inline void inc_syscw(struct task_struct *tsk)
1961{
1962        tsk->syscw++;
1963}
1964#else
1965static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
1966{
1967}
1968
1969static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
1970{
1971}
1972
1973static inline void inc_syscr(struct task_struct *tsk)
1974{
1975}
1976
1977static inline void inc_syscw(struct task_struct *tsk)
1978{
1979}
1980#endif
1981
1982#ifdef CONFIG_SMP
1983void migration_init(void);
1984#else
1985static inline void migration_init(void)
1986{
1987}
1988#endif
1989
1990#endif /* __KERNEL__ */
1991
1992#endif
1993