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#define CLONE_IO                0x80000000      /* Clone io context */
  31
  32/*
  33 * Scheduling policies
  34 */
  35#define SCHED_NORMAL            0
  36#define SCHED_FIFO              1
  37#define SCHED_RR                2
  38#define SCHED_BATCH             3
  39/* SCHED_ISO: reserved but not implemented yet */
  40#define SCHED_IDLE              5
  41
  42#ifdef __KERNEL__
  43
  44struct sched_param {
  45        int sched_priority;
  46};
  47
  48#include <asm/param.h>  /* for HZ */
  49
  50#include <linux/capability.h>
  51#include <linux/threads.h>
  52#include <linux/kernel.h>
  53#include <linux/types.h>
  54#include <linux/timex.h>
  55#include <linux/jiffies.h>
  56#include <linux/rbtree.h>
  57#include <linux/thread_info.h>
  58#include <linux/cpumask.h>
  59#include <linux/errno.h>
  60#include <linux/nodemask.h>
  61#include <linux/mm_types.h>
  62
  63#include <asm/system.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/path.h>
  72#include <linux/compiler.h>
  73#include <linux/completion.h>
  74#include <linux/pid.h>
  75#include <linux/percpu.h>
  76#include <linux/topology.h>
  77#include <linux/proportions.h>
  78#include <linux/seccomp.h>
  79#include <linux/rcupdate.h>
  80#include <linux/rtmutex.h>
  81
  82#include <linux/time.h>
  83#include <linux/param.h>
  84#include <linux/resource.h>
  85#include <linux/timer.h>
  86#include <linux/hrtimer.h>
  87#include <linux/task_io_accounting.h>
  88#include <linux/kobject.h>
  89#include <linux/latencytop.h>
  90#include <linux/cred.h>
  91
  92#include <asm/processor.h>
  93
  94struct mem_cgroup;
  95struct exec_domain;
  96struct futex_pi_state;
  97struct robust_list_head;
  98struct bio;
  99struct bts_tracer;
 100struct fs_struct;
 101
 102/*
 103 * List of flags we want to share for kernel threads,
 104 * if only because they are not used by them anyway.
 105 */
 106#define CLONE_KERNEL    (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
 107
 108/*
 109 * These are the constant used to fake the fixed-point load-average
 110 * counting. Some notes:
 111 *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
 112 *    a load-average precision of 10 bits integer + 11 bits fractional
 113 *  - if you want to count load-averages more often, you need more
 114 *    precision, or rounding will get you. With 2-second counting freq,
 115 *    the EXP_n values would be 1981, 2034 and 2043 if still using only
 116 *    11 bit fractions.
 117 */
 118extern unsigned long avenrun[];         /* Load averages */
 119
 120#define FSHIFT          11              /* nr of bits of precision */
 121#define FIXED_1         (1<<FSHIFT)     /* 1.0 as fixed-point */
 122#define LOAD_FREQ       (5*HZ+1)        /* 5 sec intervals */
 123#define EXP_1           1884            /* 1/exp(5sec/1min) as fixed-point */
 124#define EXP_5           2014            /* 1/exp(5sec/5min) */
 125#define EXP_15          2037            /* 1/exp(5sec/15min) */
 126
 127#define CALC_LOAD(load,exp,n) \
 128        load *= exp; \
 129        load += n*(FIXED_1-exp); \
 130        load >>= FSHIFT;
 131
 132extern unsigned long total_forks;
 133extern int nr_threads;
 134DECLARE_PER_CPU(unsigned long, process_counts);
 135extern int nr_processes(void);
 136extern unsigned long nr_running(void);
 137extern unsigned long nr_uninterruptible(void);
 138extern unsigned long nr_active(void);
 139extern unsigned long nr_iowait(void);
 140
 141extern unsigned long get_parent_ip(unsigned long addr);
 142
 143struct seq_file;
 144struct cfs_rq;
 145struct task_group;
 146#ifdef CONFIG_SCHED_DEBUG
 147extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
 148extern void proc_sched_set_task(struct task_struct *p);
 149extern void
 150print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
 151#else
 152static inline void
 153proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 154{
 155}
 156static inline void proc_sched_set_task(struct task_struct *p)
 157{
 158}
 159static inline void
 160print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
 161{
 162}
 163#endif
 164
 165extern unsigned long long time_sync_thresh;
 166
 167/*
 168 * Task state bitmask. NOTE! These bits are also
 169 * encoded in fs/proc/array.c: get_task_state().
 170 *
 171 * We have two separate sets of flags: task->state
 172 * is about runnability, while task->exit_state are
 173 * about the task exiting. Confusing, but this way
 174 * modifying one set can't modify the other one by
 175 * mistake.
 176 */
 177#define TASK_RUNNING            0
 178#define TASK_INTERRUPTIBLE      1
 179#define TASK_UNINTERRUPTIBLE    2
 180#define __TASK_STOPPED          4
 181#define __TASK_TRACED           8
 182/* in tsk->exit_state */
 183#define EXIT_ZOMBIE             16
 184#define EXIT_DEAD               32
 185/* in tsk->state again */
 186#define TASK_DEAD               64
 187#define TASK_WAKEKILL           128
 188
 189/* Convenience macros for the sake of set_task_state */
 190#define TASK_KILLABLE           (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
 191#define TASK_STOPPED            (TASK_WAKEKILL | __TASK_STOPPED)
 192#define TASK_TRACED             (TASK_WAKEKILL | __TASK_TRACED)
 193
 194/* Convenience macros for the sake of wake_up */
 195#define TASK_NORMAL             (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
 196#define TASK_ALL                (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
 197
 198/* get_task_state() */
 199#define TASK_REPORT             (TASK_RUNNING | TASK_INTERRUPTIBLE | \
 200                                 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
 201                                 __TASK_TRACED)
 202
 203#define task_is_traced(task)    ((task->state & __TASK_TRACED) != 0)
 204#define task_is_stopped(task)   ((task->state & __TASK_STOPPED) != 0)
 205#define task_is_stopped_or_traced(task) \
 206                        ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
 207#define task_contributes_to_load(task)  \
 208                                ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
 209                                 (task->flags & PF_FREEZING) == 0)
 210
 211#define __set_task_state(tsk, state_value)              \
 212        do { (tsk)->state = (state_value); } while (0)
 213#define set_task_state(tsk, state_value)                \
 214        set_mb((tsk)->state, (state_value))
 215
 216/*
 217 * set_current_state() includes a barrier so that the write of current->state
 218 * is correctly serialised wrt the caller's subsequent test of whether to
 219 * actually sleep:
 220 *
 221 *      set_current_state(TASK_UNINTERRUPTIBLE);
 222 *      if (do_i_need_to_sleep())
 223 *              schedule();
 224 *
 225 * If the caller does not need such serialisation then use __set_current_state()
 226 */
 227#define __set_current_state(state_value)                        \
 228        do { current->state = (state_value); } while (0)
 229#define set_current_state(state_value)          \
 230        set_mb(current->state, (state_value))
 231
 232/* Task command name length */
 233#define TASK_COMM_LEN 16
 234
 235#include <linux/spinlock.h>
 236
 237/*
 238 * This serializes "schedule()" and also protects
 239 * the run-queue from deletions/modifications (but
 240 * _adding_ to the beginning of the run-queue has
 241 * a separate lock).
 242 */
 243extern rwlock_t tasklist_lock;
 244extern spinlock_t mmlist_lock;
 245
 246struct task_struct;
 247
 248extern void sched_init(void);
 249extern void sched_init_smp(void);
 250extern asmlinkage void schedule_tail(struct task_struct *prev);
 251extern void init_idle(struct task_struct *idle, int cpu);
 252extern void init_idle_bootup_task(struct task_struct *idle);
 253
 254extern int runqueue_is_locked(void);
 255extern void task_rq_unlock_wait(struct task_struct *p);
 256
 257extern cpumask_var_t nohz_cpu_mask;
 258#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
 259extern int select_nohz_load_balancer(int cpu);
 260#else
 261static inline int select_nohz_load_balancer(int cpu)
 262{
 263        return 0;
 264}
 265#endif
 266
 267/*
 268 * Only dump TASK_* tasks. (0 for all tasks)
 269 */
 270extern void show_state_filter(unsigned long state_filter);
 271
 272static inline void show_state(void)
 273{
 274        show_state_filter(0);
 275}
 276
 277extern void show_regs(struct pt_regs *);
 278
 279/*
 280 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
 281 * task), SP is the stack pointer of the first frame that should be shown in the back
 282 * trace (or NULL if the entire call-chain of the task should be shown).
 283 */
 284extern void show_stack(struct task_struct *task, unsigned long *sp);
 285
 286void io_schedule(void);
 287long io_schedule_timeout(long timeout);
 288
 289extern void cpu_init (void);
 290extern void trap_init(void);
 291extern void update_process_times(int user);
 292extern void scheduler_tick(void);
 293
 294extern void sched_show_task(struct task_struct *p);
 295
 296#ifdef CONFIG_DETECT_SOFTLOCKUP
 297extern void softlockup_tick(void);
 298extern void touch_softlockup_watchdog(void);
 299extern void touch_all_softlockup_watchdogs(void);
 300extern int proc_dosoftlockup_thresh(struct ctl_table *table, int write,
 301                                    struct file *filp, void __user *buffer,
 302                                    size_t *lenp, loff_t *ppos);
 303extern unsigned int  softlockup_panic;
 304extern int softlockup_thresh;
 305#else
 306static inline void softlockup_tick(void)
 307{
 308}
 309static inline void touch_softlockup_watchdog(void)
 310{
 311}
 312static inline void touch_all_softlockup_watchdogs(void)
 313{
 314}
 315#endif
 316
 317#ifdef CONFIG_DETECT_HUNG_TASK
 318extern unsigned int  sysctl_hung_task_panic;
 319extern unsigned long sysctl_hung_task_check_count;
 320extern unsigned long sysctl_hung_task_timeout_secs;
 321extern unsigned long sysctl_hung_task_warnings;
 322extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
 323                                         struct file *filp, void __user *buffer,
 324                                         size_t *lenp, loff_t *ppos);
 325#endif
 326
 327/* Attach to any functions which should be ignored in wchan output. */
 328#define __sched         __attribute__((__section__(".sched.text")))
 329
 330/* Linker adds these: start and end of __sched functions */
 331extern char __sched_text_start[], __sched_text_end[];
 332
 333/* Is this address in the __sched functions? */
 334extern int in_sched_functions(unsigned long addr);
 335
 336#define MAX_SCHEDULE_TIMEOUT    LONG_MAX
 337extern signed long schedule_timeout(signed long timeout);
 338extern signed long schedule_timeout_interruptible(signed long timeout);
 339extern signed long schedule_timeout_killable(signed long timeout);
 340extern signed long schedule_timeout_uninterruptible(signed long timeout);
 341asmlinkage void __schedule(void);
 342asmlinkage void schedule(void);
 343extern int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner);
 344
 345struct nsproxy;
 346struct user_namespace;
 347
 348/* Maximum number of active map areas.. This is a random (large) number */
 349#define DEFAULT_MAX_MAP_COUNT   65536
 350
 351extern int sysctl_max_map_count;
 352
 353#include <linux/aio.h>
 354
 355extern unsigned long
 356arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
 357                       unsigned long, unsigned long);
 358extern unsigned long
 359arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
 360                          unsigned long len, unsigned long pgoff,
 361                          unsigned long flags);
 362extern void arch_unmap_area(struct mm_struct *, unsigned long);
 363extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
 364
 365#if USE_SPLIT_PTLOCKS
 366/*
 367 * The mm counters are not protected by its page_table_lock,
 368 * so must be incremented atomically.
 369 */
 370#define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
 371#define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
 372#define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
 373#define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
 374#define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
 375
 376#else  /* !USE_SPLIT_PTLOCKS */
 377/*
 378 * The mm counters are protected by its page_table_lock,
 379 * so can be incremented directly.
 380 */
 381#define set_mm_counter(mm, member, value) (mm)->_##member = (value)
 382#define get_mm_counter(mm, member) ((mm)->_##member)
 383#define add_mm_counter(mm, member, value) (mm)->_##member += (value)
 384#define inc_mm_counter(mm, member) (mm)->_##member++
 385#define dec_mm_counter(mm, member) (mm)->_##member--
 386
 387#endif /* !USE_SPLIT_PTLOCKS */
 388
 389#define get_mm_rss(mm)                                  \
 390        (get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
 391#define update_hiwater_rss(mm)  do {                    \
 392        unsigned long _rss = get_mm_rss(mm);            \
 393        if ((mm)->hiwater_rss < _rss)                   \
 394                (mm)->hiwater_rss = _rss;               \
 395} while (0)
 396#define update_hiwater_vm(mm)   do {                    \
 397        if ((mm)->hiwater_vm < (mm)->total_vm)          \
 398                (mm)->hiwater_vm = (mm)->total_vm;      \
 399} while (0)
 400
 401static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm)
 402{
 403        return max(mm->hiwater_rss, get_mm_rss(mm));
 404}
 405
 406static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm)
 407{
 408        return max(mm->hiwater_vm, mm->total_vm);
 409}
 410
 411extern void set_dumpable(struct mm_struct *mm, int value);
 412extern int get_dumpable(struct mm_struct *mm);
 413
 414/* mm flags */
 415/* dumpable bits */
 416#define MMF_DUMPABLE      0  /* core dump is permitted */
 417#define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
 418#define MMF_DUMPABLE_BITS 2
 419
 420/* coredump filter bits */
 421#define MMF_DUMP_ANON_PRIVATE   2
 422#define MMF_DUMP_ANON_SHARED    3
 423#define MMF_DUMP_MAPPED_PRIVATE 4
 424#define MMF_DUMP_MAPPED_SHARED  5
 425#define MMF_DUMP_ELF_HEADERS    6
 426#define MMF_DUMP_HUGETLB_PRIVATE 7
 427#define MMF_DUMP_HUGETLB_SHARED  8
 428#define MMF_DUMP_FILTER_SHIFT   MMF_DUMPABLE_BITS
 429#define MMF_DUMP_FILTER_BITS    7
 430#define MMF_DUMP_FILTER_MASK \
 431        (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
 432#define MMF_DUMP_FILTER_DEFAULT \
 433        ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\
 434         (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
 435
 436#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
 437# define MMF_DUMP_MASK_DEFAULT_ELF      (1 << MMF_DUMP_ELF_HEADERS)
 438#else
 439# define MMF_DUMP_MASK_DEFAULT_ELF      0
 440#endif
 441
 442struct sighand_struct {
 443        atomic_t                count;
 444        struct k_sigaction      action[_NSIG];
 445        spinlock_t              siglock;
 446        wait_queue_head_t       signalfd_wqh;
 447};
 448
 449struct pacct_struct {
 450        int                     ac_flag;
 451        long                    ac_exitcode;
 452        unsigned long           ac_mem;
 453        cputime_t               ac_utime, ac_stime;
 454        unsigned long           ac_minflt, ac_majflt;
 455};
 456
 457/**
 458 * struct task_cputime - collected CPU time counts
 459 * @utime:              time spent in user mode, in &cputime_t units
 460 * @stime:              time spent in kernel mode, in &cputime_t units
 461 * @sum_exec_runtime:   total time spent on the CPU, in nanoseconds
 462 *
 463 * This structure groups together three kinds of CPU time that are
 464 * tracked for threads and thread groups.  Most things considering
 465 * CPU time want to group these counts together and treat all three
 466 * of them in parallel.
 467 */
 468struct task_cputime {
 469        cputime_t utime;
 470        cputime_t stime;
 471        unsigned long long sum_exec_runtime;
 472};
 473/* Alternate field names when used to cache expirations. */
 474#define prof_exp        stime
 475#define virt_exp        utime
 476#define sched_exp       sum_exec_runtime
 477
 478#define INIT_CPUTIME    \
 479        (struct task_cputime) {                                 \
 480                .utime = cputime_zero,                          \
 481                .stime = cputime_zero,                          \
 482                .sum_exec_runtime = 0,                          \
 483        }
 484
 485/**
 486 * struct thread_group_cputimer - thread group interval timer counts
 487 * @cputime:            thread group interval timers.
 488 * @running:            non-zero when there are timers running and
 489 *                      @cputime receives updates.
 490 * @lock:               lock for fields in this struct.
 491 *
 492 * This structure contains the version of task_cputime, above, that is
 493 * used for thread group CPU timer calculations.
 494 */
 495struct thread_group_cputimer {
 496        struct task_cputime cputime;
 497        int running;
 498        spinlock_t lock;
 499};
 500
 501/*
 502 * NOTE! "signal_struct" does not have it's own
 503 * locking, because a shared signal_struct always
 504 * implies a shared sighand_struct, so locking
 505 * sighand_struct is always a proper superset of
 506 * the locking of signal_struct.
 507 */
 508struct signal_struct {
 509        atomic_t                count;
 510        atomic_t                live;
 511
 512        wait_queue_head_t       wait_chldexit;  /* for wait4() */
 513
 514        /* current thread group signal load-balancing target: */
 515        struct task_struct      *curr_target;
 516
 517        /* shared signal handling: */
 518        struct sigpending       shared_pending;
 519
 520        /* thread group exit support */
 521        int                     group_exit_code;
 522        /* overloaded:
 523         * - notify group_exit_task when ->count is equal to notify_count
 524         * - everyone except group_exit_task is stopped during signal delivery
 525         *   of fatal signals, group_exit_task processes the signal.
 526         */
 527        int                     notify_count;
 528        struct task_struct      *group_exit_task;
 529
 530        /* thread group stop support, overloads group_exit_code too */
 531        int                     group_stop_count;
 532        unsigned int            flags; /* see SIGNAL_* flags below */
 533
 534        /* POSIX.1b Interval Timers */
 535        struct list_head posix_timers;
 536
 537        /* ITIMER_REAL timer for the process */
 538        struct hrtimer real_timer;
 539        struct pid *leader_pid;
 540        ktime_t it_real_incr;
 541
 542        /* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
 543        cputime_t it_prof_expires, it_virt_expires;
 544        cputime_t it_prof_incr, it_virt_incr;
 545
 546        /*
 547         * Thread group totals for process CPU timers.
 548         * See thread_group_cputimer(), et al, for details.
 549         */
 550        struct thread_group_cputimer cputimer;
 551
 552        /* Earliest-expiration cache. */
 553        struct task_cputime cputime_expires;
 554
 555        struct list_head cpu_timers[3];
 556
 557        struct pid *tty_old_pgrp;
 558
 559        /* boolean value for session group leader */
 560        int leader;
 561
 562        struct tty_struct *tty; /* NULL if no tty */
 563
 564        /*
 565         * Cumulative resource counters for dead threads in the group,
 566         * and for reaped dead child processes forked by this group.
 567         * Live threads maintain their own counters and add to these
 568         * in __exit_signal, except for the group leader.
 569         */
 570        cputime_t utime, stime, cutime, cstime;
 571        cputime_t gtime;
 572        cputime_t cgtime;
 573        unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
 574        unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
 575        unsigned long inblock, oublock, cinblock, coublock;
 576        struct task_io_accounting ioac;
 577
 578        /*
 579         * Cumulative ns of schedule CPU time fo dead threads in the
 580         * group, not including a zombie group leader, (This only differs
 581         * from jiffies_to_ns(utime + stime) if sched_clock uses something
 582         * other than jiffies.)
 583         */
 584        unsigned long long sum_sched_runtime;
 585
 586        /*
 587         * We don't bother to synchronize most readers of this at all,
 588         * because there is no reader checking a limit that actually needs
 589         * to get both rlim_cur and rlim_max atomically, and either one
 590         * alone is a single word that can safely be read normally.
 591         * getrlimit/setrlimit use task_lock(current->group_leader) to
 592         * protect this instead of the siglock, because they really
 593         * have no need to disable irqs.
 594         */
 595        struct rlimit rlim[RLIM_NLIMITS];
 596
 597#ifdef CONFIG_BSD_PROCESS_ACCT
 598        struct pacct_struct pacct;      /* per-process accounting information */
 599#endif
 600#ifdef CONFIG_TASKSTATS
 601        struct taskstats *stats;
 602#endif
 603#ifdef CONFIG_AUDIT
 604        unsigned audit_tty;
 605        struct tty_audit_buf *tty_audit_buf;
 606#endif
 607};
 608
 609/* Context switch must be unlocked if interrupts are to be enabled */
 610#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
 611# define __ARCH_WANT_UNLOCKED_CTXSW
 612#endif
 613
 614/*
 615 * Bits in flags field of signal_struct.
 616 */
 617#define SIGNAL_STOP_STOPPED     0x00000001 /* job control stop in effect */
 618#define SIGNAL_STOP_DEQUEUED    0x00000002 /* stop signal dequeued */
 619#define SIGNAL_STOP_CONTINUED   0x00000004 /* SIGCONT since WCONTINUED reap */
 620#define SIGNAL_GROUP_EXIT       0x00000008 /* group exit in progress */
 621/*
 622 * Pending notifications to parent.
 623 */
 624#define SIGNAL_CLD_STOPPED      0x00000010
 625#define SIGNAL_CLD_CONTINUED    0x00000020
 626#define SIGNAL_CLD_MASK         (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
 627
 628#define SIGNAL_UNKILLABLE       0x00000040 /* for init: ignore fatal signals */
 629
 630/* If true, all threads except ->group_exit_task have pending SIGKILL */
 631static inline int signal_group_exit(const struct signal_struct *sig)
 632{
 633        return  (sig->flags & SIGNAL_GROUP_EXIT) ||
 634                (sig->group_exit_task != NULL);
 635}
 636
 637/*
 638 * Some day this will be a full-fledged user tracking system..
 639 */
 640struct user_struct {
 641        atomic_t __count;       /* reference count */
 642        atomic_t processes;     /* How many processes does this user have? */
 643        atomic_t files;         /* How many open files does this user have? */
 644        atomic_t sigpending;    /* How many pending signals does this user have? */
 645#ifdef CONFIG_INOTIFY_USER
 646        atomic_t inotify_watches; /* How many inotify watches does this user have? */
 647        atomic_t inotify_devs;  /* How many inotify devs does this user have opened? */
 648#endif
 649#ifdef CONFIG_EPOLL
 650        atomic_t epoll_watches; /* The number of file descriptors currently watched */
 651#endif
 652#ifdef CONFIG_POSIX_MQUEUE
 653        /* protected by mq_lock */
 654        unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
 655#endif
 656        unsigned long locked_shm; /* How many pages of mlocked shm ? */
 657
 658#ifdef CONFIG_KEYS
 659        struct key *uid_keyring;        /* UID specific keyring */
 660        struct key *session_keyring;    /* UID's default session keyring */
 661#endif
 662
 663        /* Hash table maintenance information */
 664        struct hlist_node uidhash_node;
 665        uid_t uid;
 666        struct user_namespace *user_ns;
 667
 668#ifdef CONFIG_USER_SCHED
 669        struct task_group *tg;
 670#ifdef CONFIG_SYSFS
 671        struct kobject kobj;
 672        struct work_struct work;
 673#endif
 674#endif
 675};
 676
 677extern int uids_sysfs_init(void);
 678
 679extern struct user_struct *find_user(uid_t);
 680
 681extern struct user_struct root_user;
 682#define INIT_USER (&root_user)
 683
 684
 685struct backing_dev_info;
 686struct reclaim_state;
 687
 688#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
 689struct sched_info {
 690        /* cumulative counters */
 691        unsigned long pcount;         /* # of times run on this cpu */
 692        unsigned long long run_delay; /* time spent waiting on a runqueue */
 693
 694        /* timestamps */
 695        unsigned long long last_arrival,/* when we last ran on a cpu */
 696                           last_queued; /* when we were last queued to run */
 697#ifdef CONFIG_SCHEDSTATS
 698        /* BKL stats */
 699        unsigned int bkl_count;
 700#endif
 701};
 702#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
 703
 704#ifdef CONFIG_TASK_DELAY_ACCT
 705struct task_delay_info {
 706        spinlock_t      lock;
 707        unsigned int    flags;  /* Private per-task flags */
 708
 709        /* For each stat XXX, add following, aligned appropriately
 710         *
 711         * struct timespec XXX_start, XXX_end;
 712         * u64 XXX_delay;
 713         * u32 XXX_count;
 714         *
 715         * Atomicity of updates to XXX_delay, XXX_count protected by
 716         * single lock above (split into XXX_lock if contention is an issue).
 717         */
 718
 719        /*
 720         * XXX_count is incremented on every XXX operation, the delay
 721         * associated with the operation is added to XXX_delay.
 722         * XXX_delay contains the accumulated delay time in nanoseconds.
 723         */
 724        struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */
 725        u64 blkio_delay;        /* wait for sync block io completion */
 726        u64 swapin_delay;       /* wait for swapin block io completion */
 727        u32 blkio_count;        /* total count of the number of sync block */
 728                                /* io operations performed */
 729        u32 swapin_count;       /* total count of the number of swapin block */
 730                                /* io operations performed */
 731
 732        struct timespec freepages_start, freepages_end;
 733        u64 freepages_delay;    /* wait for memory reclaim */
 734        u32 freepages_count;    /* total count of memory reclaim */
 735};
 736#endif  /* CONFIG_TASK_DELAY_ACCT */
 737
 738static inline int sched_info_on(void)
 739{
 740#ifdef CONFIG_SCHEDSTATS
 741        return 1;
 742#elif defined(CONFIG_TASK_DELAY_ACCT)
 743        extern int delayacct_on;
 744        return delayacct_on;
 745#else
 746        return 0;
 747#endif
 748}
 749
 750enum cpu_idle_type {
 751        CPU_IDLE,
 752        CPU_NOT_IDLE,
 753        CPU_NEWLY_IDLE,
 754        CPU_MAX_IDLE_TYPES
 755};
 756
 757/*
 758 * sched-domains (multiprocessor balancing) declarations:
 759 */
 760
 761/*
 762 * Increase resolution of nice-level calculations:
 763 */
 764#define SCHED_LOAD_SHIFT        10
 765#define SCHED_LOAD_SCALE        (1L << SCHED_LOAD_SHIFT)
 766
 767#define SCHED_LOAD_SCALE_FUZZ   SCHED_LOAD_SCALE
 768
 769#ifdef CONFIG_SMP
 770#define SD_LOAD_BALANCE         1       /* Do load balancing on this domain. */
 771#define SD_BALANCE_NEWIDLE      2       /* Balance when about to become idle */
 772#define SD_BALANCE_EXEC         4       /* Balance on exec */
 773#define SD_BALANCE_FORK         8       /* Balance on fork, clone */
 774#define SD_WAKE_IDLE            16      /* Wake to idle CPU on task wakeup */
 775#define SD_WAKE_AFFINE          32      /* Wake task to waking CPU */
 776#define SD_WAKE_BALANCE         64      /* Perform balancing at task wakeup */
 777#define SD_SHARE_CPUPOWER       128     /* Domain members share cpu power */
 778#define SD_POWERSAVINGS_BALANCE 256     /* Balance for power savings */
 779#define SD_SHARE_PKG_RESOURCES  512     /* Domain members share cpu pkg resources */
 780#define SD_SERIALIZE            1024    /* Only a single load balancing instance */
 781#define SD_WAKE_IDLE_FAR        2048    /* Gain latency sacrificing cache hit */
 782
 783enum powersavings_balance_level {
 784        POWERSAVINGS_BALANCE_NONE = 0,  /* No power saving load balance */
 785        POWERSAVINGS_BALANCE_BASIC,     /* Fill one thread/core/package
 786                                         * first for long running threads
 787                                         */
 788        POWERSAVINGS_BALANCE_WAKEUP,    /* Also bias task wakeups to semi-idle
 789                                         * cpu package for power savings
 790                                         */
 791        MAX_POWERSAVINGS_BALANCE_LEVELS
 792};
 793
 794extern int sched_mc_power_savings, sched_smt_power_savings;
 795
 796static inline int sd_balance_for_mc_power(void)
 797{
 798        if (sched_smt_power_savings)
 799                return SD_POWERSAVINGS_BALANCE;
 800
 801        return 0;
 802}
 803
 804static inline int sd_balance_for_package_power(void)
 805{
 806        if (sched_mc_power_savings | sched_smt_power_savings)
 807                return SD_POWERSAVINGS_BALANCE;
 808
 809        return 0;
 810}
 811
 812/*
 813 * Optimise SD flags for power savings:
 814 * SD_BALANCE_NEWIDLE helps agressive task consolidation and power savings.
 815 * Keep default SD flags if sched_{smt,mc}_power_saving=0
 816 */
 817
 818static inline int sd_power_saving_flags(void)
 819{
 820        if (sched_mc_power_savings | sched_smt_power_savings)
 821                return SD_BALANCE_NEWIDLE;
 822
 823        return 0;
 824}
 825
 826struct sched_group {
 827        struct sched_group *next;       /* Must be a circular list */
 828
 829        /*
 830         * CPU power of this group, SCHED_LOAD_SCALE being max power for a
 831         * single CPU. This is read only (except for setup, hotplug CPU).
 832         * Note : Never change cpu_power without recompute its reciprocal
 833         */
 834        unsigned int __cpu_power;
 835        /*
 836         * reciprocal value of cpu_power to avoid expensive divides
 837         * (see include/linux/reciprocal_div.h)
 838         */
 839        u32 reciprocal_cpu_power;
 840
 841        unsigned long cpumask[];
 842};
 843
 844static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
 845{
 846        return to_cpumask(sg->cpumask);
 847}
 848
 849enum sched_domain_level {
 850        SD_LV_NONE = 0,
 851        SD_LV_SIBLING,
 852        SD_LV_MC,
 853        SD_LV_CPU,
 854        SD_LV_NODE,
 855        SD_LV_ALLNODES,
 856        SD_LV_MAX
 857};
 858
 859struct sched_domain_attr {
 860        int relax_domain_level;
 861};
 862
 863#define SD_ATTR_INIT    (struct sched_domain_attr) {    \
 864        .relax_domain_level = -1,                       \
 865}
 866
 867struct sched_domain {
 868        /* These fields must be setup */
 869        struct sched_domain *parent;    /* top domain must be null terminated */
 870        struct sched_domain *child;     /* bottom domain must be null terminated */
 871        struct sched_group *groups;     /* the balancing groups of the domain */
 872        unsigned long min_interval;     /* Minimum balance interval ms */
 873        unsigned long max_interval;     /* Maximum balance interval ms */
 874        unsigned int busy_factor;       /* less balancing by factor if busy */
 875        unsigned int imbalance_pct;     /* No balance until over watermark */
 876        unsigned int cache_nice_tries;  /* Leave cache hot tasks for # tries */
 877        unsigned int busy_idx;
 878        unsigned int idle_idx;
 879        unsigned int newidle_idx;
 880        unsigned int wake_idx;
 881        unsigned int forkexec_idx;
 882        int flags;                      /* See SD_* */
 883        enum sched_domain_level level;
 884
 885        /* Runtime fields. */
 886        unsigned long last_balance;     /* init to jiffies. units in jiffies */
 887        unsigned int balance_interval;  /* initialise to 1. units in ms. */
 888        unsigned int nr_balance_failed; /* initialise to 0 */
 889
 890        u64 last_update;
 891
 892#ifdef CONFIG_SCHEDSTATS
 893        /* load_balance() stats */
 894        unsigned int lb_count[CPU_MAX_IDLE_TYPES];
 895        unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
 896        unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
 897        unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
 898        unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
 899        unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
 900        unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
 901        unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
 902
 903        /* Active load balancing */
 904        unsigned int alb_count;
 905        unsigned int alb_failed;
 906        unsigned int alb_pushed;
 907
 908        /* SD_BALANCE_EXEC stats */
 909        unsigned int sbe_count;
 910        unsigned int sbe_balanced;
 911        unsigned int sbe_pushed;
 912
 913        /* SD_BALANCE_FORK stats */
 914        unsigned int sbf_count;
 915        unsigned int sbf_balanced;
 916        unsigned int sbf_pushed;
 917
 918        /* try_to_wake_up() stats */
 919        unsigned int ttwu_wake_remote;
 920        unsigned int ttwu_move_affine;
 921        unsigned int ttwu_move_balance;
 922#endif
 923#ifdef CONFIG_SCHED_DEBUG
 924        char *name;
 925#endif
 926
 927        /* span of all CPUs in this domain */
 928        unsigned long span[];
 929};
 930
 931static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
 932{
 933        return to_cpumask(sd->span);
 934}
 935
 936extern void partition_sched_domains(int ndoms_new, struct cpumask *doms_new,
 937                                    struct sched_domain_attr *dattr_new);
 938
 939/* Test a flag in parent sched domain */
 940static inline int test_sd_parent(struct sched_domain *sd, int flag)
 941{
 942        if (sd->parent && (sd->parent->flags & flag))
 943                return 1;
 944
 945        return 0;
 946}
 947
 948#else /* CONFIG_SMP */
 949
 950struct sched_domain_attr;
 951
 952static inline void
 953partition_sched_domains(int ndoms_new, struct cpumask *doms_new,
 954                        struct sched_domain_attr *dattr_new)
 955{
 956}
 957#endif  /* !CONFIG_SMP */
 958
 959struct io_context;                      /* See blkdev.h */
 960
 961
 962#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
 963extern void prefetch_stack(struct task_struct *t);
 964#else
 965static inline void prefetch_stack(struct task_struct *t) { }
 966#endif
 967
 968struct audit_context;           /* See audit.c */
 969struct mempolicy;
 970struct pipe_inode_info;
 971struct uts_namespace;
 972
 973struct rq;
 974struct sched_domain;
 975
 976struct sched_class {
 977        const struct sched_class *next;
 978
 979        void (*enqueue_task) (struct rq *rq, struct task_struct *p, int wakeup);
 980        void (*dequeue_task) (struct rq *rq, struct task_struct *p, int sleep);
 981        void (*yield_task) (struct rq *rq);
 982
 983        void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int sync);
 984
 985        struct task_struct * (*pick_next_task) (struct rq *rq);
 986        void (*put_prev_task) (struct rq *rq, struct task_struct *p);
 987
 988#ifdef CONFIG_SMP
 989        int  (*select_task_rq)(struct task_struct *p, int sync);
 990
 991        unsigned long (*load_balance) (struct rq *this_rq, int this_cpu,
 992                        struct rq *busiest, unsigned long max_load_move,
 993                        struct sched_domain *sd, enum cpu_idle_type idle,
 994                        int *all_pinned, int *this_best_prio);
 995
 996        int (*move_one_task) (struct rq *this_rq, int this_cpu,
 997                              struct rq *busiest, struct sched_domain *sd,
 998                              enum cpu_idle_type idle);
 999        void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
1000        int (*needs_post_schedule) (struct rq *this_rq);
1001        void (*post_schedule) (struct rq *this_rq);
1002        void (*task_wake_up) (struct rq *this_rq, struct task_struct *task);
1003
1004        void (*set_cpus_allowed)(struct task_struct *p,
1005                                 const struct cpumask *newmask);
1006
1007        void (*rq_online)(struct rq *rq);
1008        void (*rq_offline)(struct rq *rq);
1009#endif
1010
1011        void (*set_curr_task) (struct rq *rq);
1012        void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1013        void (*task_new) (struct rq *rq, struct task_struct *p);
1014
1015        void (*switched_from) (struct rq *this_rq, struct task_struct *task,
1016                               int running);
1017        void (*switched_to) (struct rq *this_rq, struct task_struct *task,
1018                             int running);
1019        void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1020                             int oldprio, int running);
1021
1022#ifdef CONFIG_FAIR_GROUP_SCHED
1023        void (*moved_group) (struct task_struct *p);
1024#endif
1025};
1026
1027struct load_weight {
1028        unsigned long weight, inv_weight;
1029};
1030
1031/*
1032 * CFS stats for a schedulable entity (task, task-group etc)
1033 *
1034 * Current field usage histogram:
1035 *
1036 *     4 se->block_start
1037 *     4 se->run_node
1038 *     4 se->sleep_start
1039 *     6 se->load.weight
1040 */
1041struct sched_entity {
1042        struct load_weight      load;           /* for load-balancing */
1043        struct rb_node          run_node;
1044        struct list_head        group_node;
1045        unsigned int            on_rq;
1046
1047        u64                     exec_start;
1048        u64                     sum_exec_runtime;
1049        u64                     vruntime;
1050        u64                     prev_sum_exec_runtime;
1051
1052        u64                     last_wakeup;
1053        u64                     avg_overlap;
1054
1055        u64                     start_runtime;
1056        u64                     avg_wakeup;
1057        u64                     nr_migrations;
1058
1059#ifdef CONFIG_SCHEDSTATS
1060        u64                     wait_start;
1061        u64                     wait_max;
1062        u64                     wait_count;
1063        u64                     wait_sum;
1064
1065        u64                     sleep_start;
1066        u64                     sleep_max;
1067        s64                     sum_sleep_runtime;
1068
1069        u64                     block_start;
1070        u64                     block_max;
1071        u64                     exec_max;
1072        u64                     slice_max;
1073
1074        u64                     nr_migrations_cold;
1075        u64                     nr_failed_migrations_affine;
1076        u64                     nr_failed_migrations_running;
1077        u64                     nr_failed_migrations_hot;
1078        u64                     nr_forced_migrations;
1079        u64                     nr_forced2_migrations;
1080
1081        u64                     nr_wakeups;
1082        u64                     nr_wakeups_sync;
1083        u64                     nr_wakeups_migrate;
1084        u64                     nr_wakeups_local;
1085        u64                     nr_wakeups_remote;
1086        u64                     nr_wakeups_affine;
1087        u64                     nr_wakeups_affine_attempts;
1088        u64                     nr_wakeups_passive;
1089        u64                     nr_wakeups_idle;
1090#endif
1091
1092#ifdef CONFIG_FAIR_GROUP_SCHED
1093        struct sched_entity     *parent;
1094        /* rq on which this entity is (to be) queued: */
1095        struct cfs_rq           *cfs_rq;
1096        /* rq "owned" by this entity/group: */
1097        struct cfs_rq           *my_q;
1098#endif
1099};
1100
1101struct sched_rt_entity {
1102        struct list_head run_list;
1103        unsigned long timeout;
1104        unsigned int time_slice;
1105        int nr_cpus_allowed;
1106
1107        struct sched_rt_entity *back;
1108#ifdef CONFIG_RT_GROUP_SCHED
1109        struct sched_rt_entity  *parent;
1110        /* rq on which this entity is (to be) queued: */
1111        struct rt_rq            *rt_rq;
1112        /* rq "owned" by this entity/group: */
1113        struct rt_rq            *my_q;
1114#endif
1115};
1116
1117struct task_struct {
1118        volatile long state;    /* -1 unrunnable, 0 runnable, >0 stopped */
1119        void *stack;
1120        atomic_t usage;
1121        unsigned int flags;     /* per process flags, defined below */
1122        unsigned int ptrace;
1123
1124        int lock_depth;         /* BKL lock depth */
1125
1126#ifdef CONFIG_SMP
1127#ifdef __ARCH_WANT_UNLOCKED_CTXSW
1128        int oncpu;
1129#endif
1130#endif
1131
1132        int prio, static_prio, normal_prio;
1133        unsigned int rt_priority;
1134        const struct sched_class *sched_class;
1135        struct sched_entity se;
1136        struct sched_rt_entity rt;
1137
1138#ifdef CONFIG_PREEMPT_NOTIFIERS
1139        /* list of struct preempt_notifier: */
1140        struct hlist_head preempt_notifiers;
1141#endif
1142
1143        /*
1144         * fpu_counter contains the number of consecutive context switches
1145         * that the FPU is used. If this is over a threshold, the lazy fpu
1146         * saving becomes unlazy to save the trap. This is an unsigned char
1147         * so that after 256 times the counter wraps and the behavior turns
1148         * lazy again; this to deal with bursty apps that only use FPU for
1149         * a short time
1150         */
1151        unsigned char fpu_counter;
1152        s8 oomkilladj; /* OOM kill score adjustment (bit shift). */
1153#ifdef CONFIG_BLK_DEV_IO_TRACE
1154        unsigned int btrace_seq;
1155#endif
1156
1157        unsigned int policy;
1158        cpumask_t cpus_allowed;
1159
1160#ifdef CONFIG_PREEMPT_RCU
1161        int rcu_read_lock_nesting;
1162        int rcu_flipctr_idx;
1163#endif /* #ifdef CONFIG_PREEMPT_RCU */
1164
1165#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1166        struct sched_info sched_info;
1167#endif
1168
1169        struct list_head tasks;
1170        struct plist_node pushable_tasks;
1171
1172        struct mm_struct *mm, *active_mm;
1173
1174/* task state */
1175        struct linux_binfmt *binfmt;
1176        int exit_state;
1177        int exit_code, exit_signal;
1178        int pdeath_signal;  /*  The signal sent when the parent dies  */
1179        /* ??? */
1180        unsigned int personality;
1181        unsigned did_exec:1;
1182        unsigned in_execve:1;   /* Tell the LSMs that the process is doing an
1183                                 * execve */
1184        pid_t pid;
1185        pid_t tgid;
1186
1187        /* Canary value for the -fstack-protector gcc feature */
1188        unsigned long stack_canary;
1189
1190        /* 
1191         * pointers to (original) parent process, youngest child, younger sibling,
1192         * older sibling, respectively.  (p->father can be replaced with 
1193         * p->real_parent->pid)
1194         */
1195        struct task_struct *real_parent; /* real parent process */
1196        struct task_struct *parent; /* recipient of SIGCHLD, wait4() reports */
1197        /*
1198         * children/sibling forms the list of my natural children
1199         */
1200        struct list_head children;      /* list of my children */
1201        struct list_head sibling;       /* linkage in my parent's children list */
1202        struct task_struct *group_leader;       /* threadgroup leader */
1203
1204        /*
1205         * ptraced is the list of tasks this task is using ptrace on.
1206         * This includes both natural children and PTRACE_ATTACH targets.
1207         * p->ptrace_entry is p's link on the p->parent->ptraced list.
1208         */
1209        struct list_head ptraced;
1210        struct list_head ptrace_entry;
1211
1212#ifdef CONFIG_X86_PTRACE_BTS
1213        /*
1214         * This is the tracer handle for the ptrace BTS extension.
1215         * This field actually belongs to the ptracer task.
1216         */
1217        struct bts_tracer *bts;
1218        /*
1219         * The buffer to hold the BTS data.
1220         */
1221        void *bts_buffer;
1222        size_t bts_size;
1223#endif /* CONFIG_X86_PTRACE_BTS */
1224
1225        /* PID/PID hash table linkage. */
1226        struct pid_link pids[PIDTYPE_MAX];
1227        struct list_head thread_group;
1228
1229        struct completion *vfork_done;          /* for vfork() */
1230        int __user *set_child_tid;              /* CLONE_CHILD_SETTID */
1231        int __user *clear_child_tid;            /* CLONE_CHILD_CLEARTID */
1232
1233        cputime_t utime, stime, utimescaled, stimescaled;
1234        cputime_t gtime;
1235        cputime_t prev_utime, prev_stime;
1236        unsigned long nvcsw, nivcsw; /* context switch counts */
1237        struct timespec start_time;             /* monotonic time */
1238        struct timespec real_start_time;        /* boot based time */
1239/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1240        unsigned long min_flt, maj_flt;
1241
1242        struct task_cputime cputime_expires;
1243        struct list_head cpu_timers[3];
1244
1245/* process credentials */
1246        const struct cred *real_cred;   /* objective and real subjective task
1247                                         * credentials (COW) */
1248        const struct cred *cred;        /* effective (overridable) subjective task
1249                                         * credentials (COW) */
1250        struct mutex cred_exec_mutex;   /* execve vs ptrace cred calculation mutex */
1251
1252        char comm[TASK_COMM_LEN]; /* executable name excluding path
1253                                     - access with [gs]et_task_comm (which lock
1254                                       it with task_lock())
1255                                     - initialized normally by flush_old_exec */
1256/* file system info */
1257        int link_count, total_link_count;
1258#ifdef CONFIG_SYSVIPC
1259/* ipc stuff */
1260        struct sysv_sem sysvsem;
1261#endif
1262#ifdef CONFIG_DETECT_HUNG_TASK
1263/* hung task detection */
1264        unsigned long last_switch_count;
1265#endif
1266/* CPU-specific state of this task */
1267        struct thread_struct thread;
1268/* filesystem information */
1269        struct fs_struct *fs;
1270/* open file information */
1271        struct files_struct *files;
1272/* namespaces */
1273        struct nsproxy *nsproxy;
1274/* signal handlers */
1275        struct signal_struct *signal;
1276        struct sighand_struct *sighand;
1277
1278        sigset_t blocked, real_blocked;
1279        sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */
1280        struct sigpending pending;
1281
1282        unsigned long sas_ss_sp;
1283        size_t sas_ss_size;
1284        int (*notifier)(void *priv);
1285        void *notifier_data;
1286        sigset_t *notifier_mask;
1287        struct audit_context *audit_context;
1288#ifdef CONFIG_AUDITSYSCALL
1289        uid_t loginuid;
1290        unsigned int sessionid;
1291#endif
1292        seccomp_t seccomp;
1293
1294/* Thread group tracking */
1295        u32 parent_exec_id;
1296        u32 self_exec_id;
1297/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
1298        spinlock_t alloc_lock;
1299
1300#ifdef CONFIG_GENERIC_HARDIRQS
1301        /* IRQ handler threads */
1302        struct irqaction *irqaction;
1303#endif
1304
1305        /* Protection of the PI data structures: */
1306        spinlock_t pi_lock;
1307
1308#ifdef CONFIG_RT_MUTEXES
1309        /* PI waiters blocked on a rt_mutex held by this task */
1310        struct plist_head pi_waiters;
1311        /* Deadlock detection and priority inheritance handling */
1312        struct rt_mutex_waiter *pi_blocked_on;
1313#endif
1314
1315#ifdef CONFIG_DEBUG_MUTEXES
1316        /* mutex deadlock detection */
1317        struct mutex_waiter *blocked_on;
1318#endif
1319#ifdef CONFIG_TRACE_IRQFLAGS
1320        unsigned int irq_events;
1321        int hardirqs_enabled;
1322        unsigned long hardirq_enable_ip;
1323        unsigned int hardirq_enable_event;
1324        unsigned long hardirq_disable_ip;
1325        unsigned int hardirq_disable_event;
1326        int softirqs_enabled;
1327        unsigned long softirq_disable_ip;
1328        unsigned int softirq_disable_event;
1329        unsigned long softirq_enable_ip;
1330        unsigned int softirq_enable_event;
1331        int hardirq_context;
1332        int softirq_context;
1333#endif
1334#ifdef CONFIG_LOCKDEP
1335# define MAX_LOCK_DEPTH 48UL
1336        u64 curr_chain_key;
1337        int lockdep_depth;
1338        unsigned int lockdep_recursion;
1339        struct held_lock held_locks[MAX_LOCK_DEPTH];
1340        gfp_t lockdep_reclaim_gfp;
1341#endif
1342
1343/* journalling filesystem info */
1344        void *journal_info;
1345
1346/* stacked block device info */
1347        struct bio *bio_list, **bio_tail;
1348
1349/* VM state */
1350        struct reclaim_state *reclaim_state;
1351
1352        struct backing_dev_info *backing_dev_info;
1353
1354        struct io_context *io_context;
1355
1356        unsigned long ptrace_message;
1357        siginfo_t *last_siginfo; /* For ptrace use.  */
1358        struct task_io_accounting ioac;
1359#if defined(CONFIG_TASK_XACCT)
1360        u64 acct_rss_mem1;      /* accumulated rss usage */
1361        u64 acct_vm_mem1;       /* accumulated virtual memory usage */
1362        cputime_t acct_timexpd; /* stime + utime since last update */
1363#endif
1364#ifdef CONFIG_CPUSETS
1365        nodemask_t mems_allowed;
1366        int cpuset_mems_generation;
1367        int cpuset_mem_spread_rotor;
1368#endif
1369#ifdef CONFIG_CGROUPS
1370        /* Control Group info protected by css_set_lock */
1371        struct css_set *cgroups;
1372        /* cg_list protected by css_set_lock and tsk->alloc_lock */
1373        struct list_head cg_list;
1374#endif
1375#ifdef CONFIG_FUTEX
1376        struct robust_list_head __user *robust_list;
1377#ifdef CONFIG_COMPAT
1378        struct compat_robust_list_head __user *compat_robust_list;
1379#endif
1380        struct list_head pi_state_list;
1381        struct futex_pi_state *pi_state_cache;
1382#endif
1383#ifdef CONFIG_NUMA
1384        struct mempolicy *mempolicy;
1385        short il_next;
1386#endif
1387        atomic_t fs_excl;       /* holding fs exclusive resources */
1388        struct rcu_head rcu;
1389
1390        /*
1391         * cache last used pipe for splice
1392         */
1393        struct pipe_inode_info *splice_pipe;
1394#ifdef  CONFIG_TASK_DELAY_ACCT
1395        struct task_delay_info *delays;
1396#endif
1397#ifdef CONFIG_FAULT_INJECTION
1398        int make_it_fail;
1399#endif
1400        struct prop_local_single dirties;
1401#ifdef CONFIG_LATENCYTOP
1402        int latency_record_count;
1403        struct latency_record latency_record[LT_SAVECOUNT];
1404#endif
1405        /*
1406         * time slack values; these are used to round up poll() and
1407         * select() etc timeout values. These are in nanoseconds.
1408         */
1409        unsigned long timer_slack_ns;
1410        unsigned long default_timer_slack_ns;
1411
1412        struct list_head        *scm_work_list;
1413#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1414        /* Index of current stored adress in ret_stack */
1415        int curr_ret_stack;
1416        /* Stack of return addresses for return function tracing */
1417        struct ftrace_ret_stack *ret_stack;
1418        /* time stamp for last schedule */
1419        unsigned long long ftrace_timestamp;
1420        /*
1421         * Number of functions that haven't been traced
1422         * because of depth overrun.
1423         */
1424        atomic_t trace_overrun;
1425        /* Pause for the tracing */
1426        atomic_t tracing_graph_pause;
1427#endif
1428#ifdef CONFIG_TRACING
1429        /* state flags for use by tracers */
1430        unsigned long trace;
1431#endif
1432};
1433
1434/* Future-safe accessor for struct task_struct's cpus_allowed. */
1435#define tsk_cpumask(tsk) (&(tsk)->cpus_allowed)
1436
1437/*
1438 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1439 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1440 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1441 * values are inverted: lower p->prio value means higher priority.
1442 *
1443 * The MAX_USER_RT_PRIO value allows the actual maximum
1444 * RT priority to be separate from the value exported to
1445 * user-space.  This allows kernel threads to set their
1446 * priority to a value higher than any user task. Note:
1447 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1448 */
1449
1450#define MAX_USER_RT_PRIO        100
1451#define MAX_RT_PRIO             MAX_USER_RT_PRIO
1452
1453#define MAX_PRIO                (MAX_RT_PRIO + 40)
1454#define DEFAULT_PRIO            (MAX_RT_PRIO + 20)
1455
1456static inline int rt_prio(int prio)
1457{
1458        if (unlikely(prio < MAX_RT_PRIO))
1459                return 1;
1460        return 0;
1461}
1462
1463static inline int rt_task(struct task_struct *p)
1464{
1465        return rt_prio(p->prio);
1466}
1467
1468static inline struct pid *task_pid(struct task_struct *task)
1469{
1470        return task->pids[PIDTYPE_PID].pid;
1471}
1472
1473static inline struct pid *task_tgid(struct task_struct *task)
1474{
1475        return task->group_leader->pids[PIDTYPE_PID].pid;
1476}
1477
1478/*
1479 * Without tasklist or rcu lock it is not safe to dereference
1480 * the result of task_pgrp/task_session even if task == current,
1481 * we can race with another thread doing sys_setsid/sys_setpgid.
1482 */
1483static inline struct pid *task_pgrp(struct task_struct *task)
1484{
1485        return task->group_leader->pids[PIDTYPE_PGID].pid;
1486}
1487
1488static inline struct pid *task_session(struct task_struct *task)
1489{
1490        return task->group_leader->pids[PIDTYPE_SID].pid;
1491}
1492
1493struct pid_namespace;
1494
1495/*
1496 * the helpers to get the task's different pids as they are seen
1497 * from various namespaces
1498 *
1499 * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1500 * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1501 *                     current.
1502 * task_xid_nr_ns()  : id seen from the ns specified;
1503 *
1504 * set_task_vxid()   : assigns a virtual id to a task;
1505 *
1506 * see also pid_nr() etc in include/linux/pid.h
1507 */
1508pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1509                        struct pid_namespace *ns);
1510
1511static inline pid_t task_pid_nr(struct task_struct *tsk)
1512{
1513        return tsk->pid;
1514}
1515
1516static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1517                                        struct pid_namespace *ns)
1518{
1519        return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1520}
1521
1522static inline pid_t task_pid_vnr(struct task_struct *tsk)
1523{
1524        return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1525}
1526
1527
1528static inline pid_t task_tgid_nr(struct task_struct *tsk)
1529{
1530        return tsk->tgid;
1531}
1532
1533pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1534
1535static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1536{
1537        return pid_vnr(task_tgid(tsk));
1538}
1539
1540
1541static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1542                                        struct pid_namespace *ns)
1543{
1544        return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1545}
1546
1547static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1548{
1549        return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1550}
1551
1552
1553static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1554                                        struct pid_namespace *ns)
1555{
1556        return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1557}
1558
1559static inline pid_t task_session_vnr(struct task_struct *tsk)
1560{
1561        return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1562}
1563
1564/* obsolete, do not use */
1565static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1566{
1567        return task_pgrp_nr_ns(tsk, &init_pid_ns);
1568}
1569
1570/**
1571 * pid_alive - check that a task structure is not stale
1572 * @p: Task structure to be checked.
1573 *
1574 * Test if a process is not yet dead (at most zombie state)
1575 * If pid_alive fails, then pointers within the task structure
1576 * can be stale and must not be dereferenced.
1577 */
1578static inline int pid_alive(struct task_struct *p)
1579{
1580        return p->pids[PIDTYPE_PID].pid != NULL;
1581}
1582
1583/**
1584 * is_global_init - check if a task structure is init
1585 * @tsk: Task structure to be checked.
1586 *
1587 * Check if a task structure is the first user space task the kernel created.
1588 */
1589static inline int is_global_init(struct task_struct *tsk)
1590{
1591        return tsk->pid == 1;
1592}
1593
1594/*
1595 * is_container_init:
1596 * check whether in the task is init in its own pid namespace.
1597 */
1598extern int is_container_init(struct task_struct *tsk);
1599
1600extern struct pid *cad_pid;
1601
1602extern void free_task(struct task_struct *tsk);
1603#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1604
1605extern void __put_task_struct(struct task_struct *t);
1606
1607static inline void put_task_struct(struct task_struct *t)
1608{
1609        if (atomic_dec_and_test(&t->usage))
1610                __put_task_struct(t);
1611}
1612
1613extern cputime_t task_utime(struct task_struct *p);
1614extern cputime_t task_stime(struct task_struct *p);
1615extern cputime_t task_gtime(struct task_struct *p);
1616
1617/*
1618 * Per process flags
1619 */
1620#define PF_ALIGNWARN    0x00000001      /* Print alignment warning msgs */
1621                                        /* Not implemented yet, only for 486*/
1622#define PF_STARTING     0x00000002      /* being created */
1623#define PF_EXITING      0x00000004      /* getting shut down */
1624#define PF_EXITPIDONE   0x00000008      /* pi exit done on shut down */
1625#define PF_VCPU         0x00000010      /* I'm a virtual CPU */
1626#define PF_FORKNOEXEC   0x00000040      /* forked but didn't exec */
1627#define PF_SUPERPRIV    0x00000100      /* used super-user privileges */
1628#define PF_DUMPCORE     0x00000200      /* dumped core */
1629#define PF_SIGNALED     0x00000400      /* killed by a signal */
1630#define PF_MEMALLOC     0x00000800      /* Allocating memory */
1631#define PF_FLUSHER      0x00001000      /* responsible for disk writeback */
1632#define PF_USED_MATH    0x00002000      /* if unset the fpu must be initialized before use */
1633#define PF_FREEZING     0x00004000      /* freeze in progress. do not account to load */
1634#define PF_NOFREEZE     0x00008000      /* this thread should not be frozen */
1635#define PF_FROZEN       0x00010000      /* frozen for system suspend */
1636#define PF_FSTRANS      0x00020000      /* inside a filesystem transaction */
1637#define PF_KSWAPD       0x00040000      /* I am kswapd */
1638#define PF_SWAPOFF      0x00080000      /* I am in swapoff */
1639#define PF_LESS_THROTTLE 0x00100000     /* Throttle me less: I clean memory */
1640#define PF_KTHREAD      0x00200000      /* I am a kernel thread */
1641#define PF_RANDOMIZE    0x00400000      /* randomize virtual address space */
1642#define PF_SWAPWRITE    0x00800000      /* Allowed to write to swap */
1643#define PF_SPREAD_PAGE  0x01000000      /* Spread page cache over cpuset */
1644#define PF_SPREAD_SLAB  0x02000000      /* Spread some slab caches over cpuset */
1645#define PF_THREAD_BOUND 0x04000000      /* Thread bound to specific cpu */
1646#define PF_MEMPOLICY    0x10000000      /* Non-default NUMA mempolicy */
1647#define PF_MUTEX_TESTER 0x20000000      /* Thread belongs to the rt mutex tester */
1648#define PF_FREEZER_SKIP 0x40000000      /* Freezer should not count it as freezeable */
1649#define PF_FREEZER_NOSIG 0x80000000     /* Freezer won't send signals to it */
1650
1651/*
1652 * Only the _current_ task can read/write to tsk->flags, but other
1653 * tasks can access tsk->flags in readonly mode for example
1654 * with tsk_used_math (like during threaded core dumping).
1655 * There is however an exception to this rule during ptrace
1656 * or during fork: the ptracer task is allowed to write to the
1657 * child->flags of its traced child (same goes for fork, the parent
1658 * can write to the child->flags), because we're guaranteed the
1659 * child is not running and in turn not changing child->flags
1660 * at the same time the parent does it.
1661 */
1662#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1663#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1664#define clear_used_math() clear_stopped_child_used_math(current)
1665#define set_used_math() set_stopped_child_used_math(current)
1666#define conditional_stopped_child_used_math(condition, child) \
1667        do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1668#define conditional_used_math(condition) \
1669        conditional_stopped_child_used_math(condition, current)
1670#define copy_to_stopped_child_used_math(child) \
1671        do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1672/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1673#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1674#define used_math() tsk_used_math(current)
1675
1676#ifdef CONFIG_SMP
1677extern int set_cpus_allowed_ptr(struct task_struct *p,
1678                                const struct cpumask *new_mask);
1679#else
1680static inline int set_cpus_allowed_ptr(struct task_struct *p,
1681                                       const struct cpumask *new_mask)
1682{
1683        if (!cpumask_test_cpu(0, new_mask))
1684                return -EINVAL;
1685        return 0;
1686}
1687#endif
1688static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1689{
1690        return set_cpus_allowed_ptr(p, &new_mask);
1691}
1692
1693/*
1694 * Architectures can set this to 1 if they have specified
1695 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
1696 * but then during bootup it turns out that sched_clock()
1697 * is reliable after all:
1698 */
1699#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1700extern int sched_clock_stable;
1701#endif
1702
1703extern unsigned long long sched_clock(void);
1704
1705extern void sched_clock_init(void);
1706extern u64 sched_clock_cpu(int cpu);
1707
1708#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1709static inline void sched_clock_tick(void)
1710{
1711}
1712
1713static inline void sched_clock_idle_sleep_event(void)
1714{
1715}
1716
1717static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
1718{
1719}
1720#else
1721extern void sched_clock_tick(void);
1722extern void sched_clock_idle_sleep_event(void);
1723extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1724#endif
1725
1726/*
1727 * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
1728 * clock constructed from sched_clock():
1729 */
1730extern unsigned long long cpu_clock(int cpu);
1731
1732extern unsigned long long
1733task_sched_runtime(struct task_struct *task);
1734extern unsigned long long thread_group_sched_runtime(struct task_struct *task);
1735
1736/* sched_exec is called by processes performing an exec */
1737#ifdef CONFIG_SMP
1738extern void sched_exec(void);
1739#else
1740#define sched_exec()   {}
1741#endif
1742
1743extern void sched_clock_idle_sleep_event(void);
1744extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1745
1746#ifdef CONFIG_HOTPLUG_CPU
1747extern void idle_task_exit(void);
1748#else
1749static inline void idle_task_exit(void) {}
1750#endif
1751
1752extern void sched_idle_next(void);
1753
1754#if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
1755extern void wake_up_idle_cpu(int cpu);
1756#else
1757static inline void wake_up_idle_cpu(int cpu) { }
1758#endif
1759
1760extern unsigned int sysctl_sched_latency;
1761extern unsigned int sysctl_sched_min_granularity;
1762extern unsigned int sysctl_sched_wakeup_granularity;
1763extern unsigned int sysctl_sched_shares_ratelimit;
1764extern unsigned int sysctl_sched_shares_thresh;
1765#ifdef CONFIG_SCHED_DEBUG
1766extern unsigned int sysctl_sched_child_runs_first;
1767extern unsigned int sysctl_sched_features;
1768extern unsigned int sysctl_sched_migration_cost;
1769extern unsigned int sysctl_sched_nr_migrate;
1770
1771int sched_nr_latency_handler(struct ctl_table *table, int write,
1772                struct file *file, void __user *buffer, size_t *length,
1773                loff_t *ppos);
1774#endif
1775extern unsigned int sysctl_sched_rt_period;
1776extern int sysctl_sched_rt_runtime;
1777
1778int sched_rt_handler(struct ctl_table *table, int write,
1779                struct file *filp, void __user *buffer, size_t *lenp,
1780                loff_t *ppos);
1781
1782extern unsigned int sysctl_sched_compat_yield;
1783
1784#ifdef CONFIG_RT_MUTEXES
1785extern int rt_mutex_getprio(struct task_struct *p);
1786extern void rt_mutex_setprio(struct task_struct *p, int prio);
1787extern void rt_mutex_adjust_pi(struct task_struct *p);
1788#else
1789static inline int rt_mutex_getprio(struct task_struct *p)
1790{
1791        return p->normal_prio;
1792}
1793# define rt_mutex_adjust_pi(p)          do { } while (0)
1794#endif
1795
1796extern void set_user_nice(struct task_struct *p, long nice);
1797extern int task_prio(const struct task_struct *p);
1798extern int task_nice(const struct task_struct *p);
1799extern int can_nice(const struct task_struct *p, const int nice);
1800extern int task_curr(const struct task_struct *p);
1801extern int idle_cpu(int cpu);
1802extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1803extern int sched_setscheduler_nocheck(struct task_struct *, int,
1804                                      struct sched_param *);
1805extern struct task_struct *idle_task(int cpu);
1806extern struct task_struct *curr_task(int cpu);
1807extern void set_curr_task(int cpu, struct task_struct *p);
1808
1809void yield(void);
1810
1811/*
1812 * The default (Linux) execution domain.
1813 */
1814extern struct exec_domain       default_exec_domain;
1815
1816union thread_union {
1817        struct thread_info thread_info;
1818        unsigned long stack[THREAD_SIZE/sizeof(long)];
1819};
1820
1821#ifndef __HAVE_ARCH_KSTACK_END
1822static inline int kstack_end(void *addr)
1823{
1824        /* Reliable end of stack detection:
1825         * Some APM bios versions misalign the stack
1826         */
1827        return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1828}
1829#endif
1830
1831extern union thread_union init_thread_union;
1832extern struct task_struct init_task;
1833
1834extern struct   mm_struct init_mm;
1835
1836extern struct pid_namespace init_pid_ns;
1837
1838/*
1839 * find a task by one of its numerical ids
1840 *
1841 * find_task_by_pid_type_ns():
1842 *      it is the most generic call - it finds a task by all id,
1843 *      type and namespace specified
1844 * find_task_by_pid_ns():
1845 *      finds a task by its pid in the specified namespace
1846 * find_task_by_vpid():
1847 *      finds a task by its virtual pid
1848 *
1849 * see also find_vpid() etc in include/linux/pid.h
1850 */
1851
1852extern struct task_struct *find_task_by_pid_type_ns(int type, int pid,
1853                struct pid_namespace *ns);
1854
1855extern struct task_struct *find_task_by_vpid(pid_t nr);
1856extern struct task_struct *find_task_by_pid_ns(pid_t nr,
1857                struct pid_namespace *ns);
1858
1859extern void __set_special_pids(struct pid *pid);
1860
1861/* per-UID process charging. */
1862extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
1863static inline struct user_struct *get_uid(struct user_struct *u)
1864{
1865        atomic_inc(&u->__count);
1866        return u;
1867}
1868extern void free_uid(struct user_struct *);
1869extern void release_uids(struct user_namespace *ns);
1870
1871#include <asm/current.h>
1872
1873extern void do_timer(unsigned long ticks);
1874
1875extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1876extern int wake_up_process(struct task_struct *tsk);
1877extern void wake_up_new_task(struct task_struct *tsk,
1878                                unsigned long clone_flags);
1879#ifdef CONFIG_SMP
1880 extern void kick_process(struct task_struct *tsk);
1881#else
1882 static inline void kick_process(struct task_struct *tsk) { }
1883#endif
1884extern void sched_fork(struct task_struct *p, int clone_flags);
1885extern void sched_dead(struct task_struct *p);
1886
1887extern void proc_caches_init(void);
1888extern void flush_signals(struct task_struct *);
1889extern void ignore_signals(struct task_struct *);
1890extern void flush_signal_handlers(struct task_struct *, int force_default);
1891extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1892
1893static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1894{
1895        unsigned long flags;
1896        int ret;
1897
1898        spin_lock_irqsave(&tsk->sighand->siglock, flags);
1899        ret = dequeue_signal(tsk, mask, info);
1900        spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1901
1902        return ret;
1903}       
1904
1905extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1906                              sigset_t *mask);
1907extern void unblock_all_signals(void);
1908extern void release_task(struct task_struct * p);
1909extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1910extern int force_sigsegv(int, struct task_struct *);
1911extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1912extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1913extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
1914extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
1915extern int kill_pgrp(struct pid *pid, int sig, int priv);
1916extern int kill_pid(struct pid *pid, int sig, int priv);
1917extern int kill_proc_info(int, struct siginfo *, pid_t);
1918extern int do_notify_parent(struct task_struct *, int);
1919extern void force_sig(int, struct task_struct *);
1920extern void force_sig_specific(int, struct task_struct *);
1921extern int send_sig(int, struct task_struct *, int);
1922extern void zap_other_threads(struct task_struct *p);
1923extern struct sigqueue *sigqueue_alloc(void);
1924extern void sigqueue_free(struct sigqueue *);
1925extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
1926extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
1927extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1928
1929static inline int kill_cad_pid(int sig, int priv)
1930{
1931        return kill_pid(cad_pid, sig, priv);
1932}
1933
1934/* These can be the second arg to send_sig_info/send_group_sig_info.  */
1935#define SEND_SIG_NOINFO ((struct siginfo *) 0)
1936#define SEND_SIG_PRIV   ((struct siginfo *) 1)
1937#define SEND_SIG_FORCED ((struct siginfo *) 2)
1938
1939static inline int is_si_special(const struct siginfo *info)
1940{
1941        return info <= SEND_SIG_FORCED;
1942}
1943
1944/* True if we are on the alternate signal stack.  */
1945
1946static inline int on_sig_stack(unsigned long sp)
1947{
1948        return (sp - current->sas_ss_sp < current->sas_ss_size);
1949}
1950
1951static inline int sas_ss_flags(unsigned long sp)
1952{
1953        return (current->sas_ss_size == 0 ? SS_DISABLE
1954                : on_sig_stack(sp) ? SS_ONSTACK : 0);
1955}
1956
1957/*
1958 * Routines for handling mm_structs
1959 */
1960extern struct mm_struct * mm_alloc(void);
1961
1962/* mmdrop drops the mm and the page tables */
1963extern void __mmdrop(struct mm_struct *);
1964static inline void mmdrop(struct mm_struct * mm)
1965{
1966        if (unlikely(atomic_dec_and_test(&mm->mm_count)))
1967                __mmdrop(mm);
1968}
1969
1970/* mmput gets rid of the mappings and all user-space */
1971extern void mmput(struct mm_struct *);
1972/* Grab a reference to a task's mm, if it is not already going away */
1973extern struct mm_struct *get_task_mm(struct task_struct *task);
1974/* Remove the current tasks stale references to the old mm_struct */
1975extern void mm_release(struct task_struct *, struct mm_struct *);
1976/* Allocate a new mm structure and copy contents from tsk->mm */
1977extern struct mm_struct *dup_mm(struct task_struct *tsk);
1978
1979extern int copy_thread(unsigned long, unsigned long, unsigned long,
1980                        struct task_struct *, struct pt_regs *);
1981extern void flush_thread(void);
1982extern void exit_thread(void);
1983
1984extern void exit_files(struct task_struct *);
1985extern void __cleanup_signal(struct signal_struct *);
1986extern void __cleanup_sighand(struct sighand_struct *);
1987
1988extern void exit_itimers(struct signal_struct *);
1989extern void flush_itimer_signals(void);
1990
1991extern NORET_TYPE void do_group_exit(int);
1992
1993extern void daemonize(const char *, ...);
1994extern int allow_signal(int);
1995extern int disallow_signal(int);
1996
1997extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1998extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
1999struct task_struct *fork_idle(int);
2000
2001extern void set_task_comm(struct task_struct *tsk, char *from);
2002extern char *get_task_comm(char *to, struct task_struct *tsk);
2003
2004#ifdef CONFIG_SMP
2005extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2006#else
2007static inline unsigned long wait_task_inactive(struct task_struct *p,
2008                                               long match_state)
2009{
2010        return 1;
2011}
2012#endif
2013
2014#define next_task(p)    list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
2015
2016#define for_each_process(p) \
2017        for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2018
2019extern bool is_single_threaded(struct task_struct *);
2020
2021/*
2022 * Careful: do_each_thread/while_each_thread is a double loop so
2023 *          'break' will not work as expected - use goto instead.
2024 */
2025#define do_each_thread(g, t) \
2026        for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2027
2028#define while_each_thread(g, t) \
2029        while ((t = next_thread(t)) != g)
2030
2031/* de_thread depends on thread_group_leader not being a pid based check */
2032#define thread_group_leader(p)  (p == p->group_leader)
2033
2034/* Do to the insanities of de_thread it is possible for a process
2035 * to have the pid of the thread group leader without actually being
2036 * the thread group leader.  For iteration through the pids in proc
2037 * all we care about is that we have a task with the appropriate
2038 * pid, we don't actually care if we have the right task.
2039 */
2040static inline int has_group_leader_pid(struct task_struct *p)
2041{
2042        return p->pid == p->tgid;
2043}
2044
2045static inline
2046int same_thread_group(struct task_struct *p1, struct task_struct *p2)
2047{
2048        return p1->tgid == p2->tgid;
2049}
2050
2051static inline struct task_struct *next_thread(const struct task_struct *p)
2052{
2053        return list_entry(rcu_dereference(p->thread_group.next),
2054                          struct task_struct, thread_group);
2055}
2056
2057static inline int thread_group_empty(struct task_struct *p)
2058{
2059        return list_empty(&p->thread_group);
2060}
2061
2062#define delay_group_leader(p) \
2063                (thread_group_leader(p) && !thread_group_empty(p))
2064
2065static inline int task_detached(struct task_struct *p)
2066{
2067        return p->exit_signal == -1;
2068}
2069
2070/*
2071 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2072 * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2073 * pins the final release of task.io_context.  Also protects ->cpuset and
2074 * ->cgroup.subsys[].
2075 *
2076 * Nests both inside and outside of read_lock(&tasklist_lock).
2077 * It must not be nested with write_lock_irq(&tasklist_lock),
2078 * neither inside nor outside.
2079 */
2080static inline void task_lock(struct task_struct *p)
2081{
2082        spin_lock(&p->alloc_lock);
2083}
2084
2085static inline void task_unlock(struct task_struct *p)
2086{
2087        spin_unlock(&p->alloc_lock);
2088}
2089
2090extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2091                                                        unsigned long *flags);
2092
2093static inline void unlock_task_sighand(struct task_struct *tsk,
2094                                                unsigned long *flags)
2095{
2096        spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2097}
2098
2099#ifndef __HAVE_THREAD_FUNCTIONS
2100
2101#define task_thread_info(task)  ((struct thread_info *)(task)->stack)
2102#define task_stack_page(task)   ((task)->stack)
2103
2104static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2105{
2106        *task_thread_info(p) = *task_thread_info(org);
2107        task_thread_info(p)->task = p;
2108}
2109
2110static inline unsigned long *end_of_stack(struct task_struct *p)
2111{
2112        return (unsigned long *)(task_thread_info(p) + 1);
2113}
2114
2115#endif
2116
2117static inline int object_is_on_stack(void *obj)
2118{
2119        void *stack = task_stack_page(current);
2120
2121        return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2122}
2123
2124extern void thread_info_cache_init(void);
2125
2126#ifdef CONFIG_DEBUG_STACK_USAGE
2127static inline unsigned long stack_not_used(struct task_struct *p)
2128{
2129        unsigned long *n = end_of_stack(p);
2130
2131        do {    /* Skip over canary */
2132                n++;
2133        } while (!*n);
2134
2135        return (unsigned long)n - (unsigned long)end_of_stack(p);
2136}
2137#endif
2138
2139/* set thread flags in other task's structures
2140 * - see asm/thread_info.h for TIF_xxxx flags available
2141 */
2142static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2143{
2144        set_ti_thread_flag(task_thread_info(tsk), flag);
2145}
2146
2147static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2148{
2149        clear_ti_thread_flag(task_thread_info(tsk), flag);
2150}
2151
2152static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2153{
2154        return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2155}
2156
2157static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2158{
2159        return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2160}
2161
2162static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2163{
2164        return test_ti_thread_flag(task_thread_info(tsk), flag);
2165}
2166
2167static inline void set_tsk_need_resched(struct task_struct *tsk)
2168{
2169        set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2170}
2171
2172static inline void clear_tsk_need_resched(struct task_struct *tsk)
2173{
2174        clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2175}
2176
2177static inline int test_tsk_need_resched(struct task_struct *tsk)
2178{
2179        return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2180}
2181
2182static inline int signal_pending(struct task_struct *p)
2183{
2184        return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2185}
2186
2187extern int __fatal_signal_pending(struct task_struct *p);
2188
2189static inline int fatal_signal_pending(struct task_struct *p)
2190{
2191        return signal_pending(p) && __fatal_signal_pending(p);
2192}
2193
2194static inline int signal_pending_state(long state, struct task_struct *p)
2195{
2196        if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2197                return 0;
2198        if (!signal_pending(p))
2199                return 0;
2200
2201        return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2202}
2203
2204static inline int need_resched(void)
2205{
2206        return unlikely(test_thread_flag(TIF_NEED_RESCHED));
2207}
2208
2209/*
2210 * cond_resched() and cond_resched_lock(): latency reduction via
2211 * explicit rescheduling in places that are safe. The return
2212 * value indicates whether a reschedule was done in fact.
2213 * cond_resched_lock() will drop the spinlock before scheduling,
2214 * cond_resched_softirq() will enable bhs before scheduling.
2215 */
2216extern int _cond_resched(void);
2217#ifdef CONFIG_PREEMPT_BKL
2218static inline int cond_resched(void)
2219{
2220        return 0;
2221}
2222#else
2223static inline int cond_resched(void)
2224{
2225        return _cond_resched();
2226}
2227#endif
2228extern int cond_resched_lock(spinlock_t * lock);
2229extern int cond_resched_softirq(void);
2230static inline int cond_resched_bkl(void)
2231{
2232        return _cond_resched();
2233}
2234
2235/*
2236 * Does a critical section need to be broken due to another
2237 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2238 * but a general need for low latency)
2239 */
2240static inline int spin_needbreak(spinlock_t *lock)
2241{
2242#ifdef CONFIG_PREEMPT
2243        return spin_is_contended(lock);
2244#else
2245        return 0;
2246#endif
2247}
2248
2249/*
2250 * Thread group CPU time accounting.
2251 */
2252void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2253void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2254
2255static inline void thread_group_cputime_init(struct signal_struct *sig)
2256{
2257        sig->cputimer.cputime = INIT_CPUTIME;
2258        spin_lock_init(&sig->cputimer.lock);
2259        sig->cputimer.running = 0;
2260}
2261
2262static inline void thread_group_cputime_free(struct signal_struct *sig)
2263{
2264}
2265
2266/*
2267 * Reevaluate whether the task has signals pending delivery.
2268 * Wake the task if so.
2269 * This is required every time the blocked sigset_t changes.
2270 * callers must hold sighand->siglock.
2271 */
2272extern void recalc_sigpending_and_wake(struct task_struct *t);
2273extern void recalc_sigpending(void);
2274
2275extern void signal_wake_up(struct task_struct *t, int resume_stopped);
2276
2277/*
2278 * Wrappers for p->thread_info->cpu access. No-op on UP.
2279 */
2280#ifdef CONFIG_SMP
2281
2282static inline unsigned int task_cpu(const struct task_struct *p)
2283{
2284        return task_thread_info(p)->cpu;
2285}
2286
2287extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2288
2289#else
2290
2291static inline unsigned int task_cpu(const struct task_struct *p)
2292{
2293        return 0;
2294}
2295
2296static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2297{
2298}
2299
2300#endif /* CONFIG_SMP */
2301
2302extern void arch_pick_mmap_layout(struct mm_struct *mm);
2303
2304#ifdef CONFIG_TRACING
2305extern void
2306__trace_special(void *__tr, void *__data,
2307                unsigned long arg1, unsigned long arg2, unsigned long arg3);
2308#else
2309static inline void
2310__trace_special(void *__tr, void *__data,
2311                unsigned long arg1, unsigned long arg2, unsigned long arg3)
2312{
2313}
2314#endif
2315
2316extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2317extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2318
2319extern void normalize_rt_tasks(void);
2320
2321#ifdef CONFIG_GROUP_SCHED
2322
2323extern struct task_group init_task_group;
2324#ifdef CONFIG_USER_SCHED
2325extern struct task_group root_task_group;
2326extern void set_tg_uid(struct user_struct *user);
2327#endif
2328
2329extern struct task_group *sched_create_group(struct task_group *parent);
2330extern void sched_destroy_group(struct task_group *tg);
2331extern void sched_move_task(struct task_struct *tsk);
2332#ifdef CONFIG_FAIR_GROUP_SCHED
2333extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2334extern unsigned long sched_group_shares(struct task_group *tg);
2335#endif
2336#ifdef CONFIG_RT_GROUP_SCHED
2337extern int sched_group_set_rt_runtime(struct task_group *tg,
2338                                      long rt_runtime_us);
2339extern long sched_group_rt_runtime(struct task_group *tg);
2340extern int sched_group_set_rt_period(struct task_group *tg,
2341                                      long rt_period_us);
2342extern long sched_group_rt_period(struct task_group *tg);
2343extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
2344#endif
2345#endif
2346
2347extern int task_can_switch_user(struct user_struct *up,
2348                                        struct task_struct *tsk);
2349
2350#ifdef CONFIG_TASK_XACCT
2351static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2352{
2353        tsk->ioac.rchar += amt;
2354}
2355
2356static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2357{
2358        tsk->ioac.wchar += amt;
2359}
2360
2361static inline void inc_syscr(struct task_struct *tsk)
2362{
2363        tsk->ioac.syscr++;
2364}
2365
2366static inline void inc_syscw(struct task_struct *tsk)
2367{
2368        tsk->ioac.syscw++;
2369}
2370#else
2371static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2372{
2373}
2374
2375static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2376{
2377}
2378
2379static inline void inc_syscr(struct task_struct *tsk)
2380{
2381}
2382
2383static inline void inc_syscw(struct task_struct *tsk)
2384{
2385}
2386#endif
2387
2388#ifndef TASK_SIZE_OF
2389#define TASK_SIZE_OF(tsk)       TASK_SIZE
2390#endif
2391
2392#ifdef CONFIG_MM_OWNER
2393extern void mm_update_next_owner(struct mm_struct *mm);
2394extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2395#else
2396static inline void mm_update_next_owner(struct mm_struct *mm)
2397{
2398}
2399
2400static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2401{
2402}
2403#endif /* CONFIG_MM_OWNER */
2404
2405#define TASK_STATE_TO_CHAR_STR "RSDTtZX"
2406
2407#endif /* __KERNEL__ */
2408
2409#endif
2410
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