linuxthreads/internals.h

   1 /* Linuxthreads - a simple clone()-based implementation of Posix        */
   2 /* threads for Linux.                                                   */
   3 /* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr)              */
   4 /*                                                                      */
   5 /* This program is free software; you can redistribute it and/or        */
   6 /* modify it under the terms of the GNU Library General Public License  */
   7 /* as published by the Free Software Foundation; either version 2       */
   8 /* of the License, or (at your option) any later version.               */
   9 /*                                                                      */
  10 /* This program is distributed in the hope that it will be useful,      */
  11 /* but WITHOUT ANY WARRANTY; without even the implied warranty of       */
  12 /* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        */
  13 /* GNU Library General Public License for more details.                 */
  14
  15 #ifndef _INTERNALS_H
  16 #define _INTERNALS_H    1
  17
  18 /* Internal data structures */
  19
  20 /* Includes */
  21
  22 #include <limits.h>
  23 #include <resolv.h>
  24 #include <setjmp.h>
  25 #include <signal.h>
  26 #include <unistd.h>
  27 #include <sys/types.h>
  28 #include <bits/libc-tsd.h> /* for _LIBC_TSD_KEY_N */
  29
  30 extern long int testandset (int *spinlock);
  31 extern int __compare_and_swap (long int *p, long int oldval, long int newval);
  32
  33 #include "pt-machine.h"
  34 #include "semaphore.h"
  35 #include "../linuxthreads_db/thread_dbP.h"
  36 #include <hp-timing.h>
  37
  38 #ifndef THREAD_GETMEM
  39 # define THREAD_GETMEM(descr, member) descr->member
  40 #endif
  41 #ifndef THREAD_GETMEM_NC
  42 # define THREAD_GETMEM_NC(descr, member) descr->member
  43 #endif
  44 #ifndef THREAD_SETMEM
  45 # define THREAD_SETMEM(descr, member, value) descr->member = (value)
  46 #endif
  47 #ifndef THREAD_SETMEM_NC
  48 # define THREAD_SETMEM_NC(descr, member, value) descr->member = (value)
  49 #endif
  50
  51 /* Arguments passed to thread creation routine */
  52
  53 struct pthread_start_args {
  54   void * (*start_routine)(void *); /* function to run */
  55   void * arg;                   /* its argument */
  56   sigset_t mask;                /* initial signal mask for thread */
  57   int schedpolicy;              /* initial scheduling policy (if any) */
  58   struct sched_param schedparam; /* initial scheduling parameters (if any) */
  59 };
  60
  61
  62 /* We keep thread specific data in a special data structure, a two-level
  63    array.  The top-level array contains pointers to dynamically allocated
  64    arrays of a certain number of data pointers.  So we can implement a
  65    sparse array.  Each dynamic second-level array has
  66         PTHREAD_KEY_2NDLEVEL_SIZE
  67    entries.  This value shouldn't be too large.  */
  68 #define PTHREAD_KEY_2NDLEVEL_SIZE       32
  69
  70 /* We need to address PTHREAD_KEYS_MAX key with PTHREAD_KEY_2NDLEVEL_SIZE
  71    keys in each subarray.  */
  72 #define PTHREAD_KEY_1STLEVEL_SIZE \
  73   ((PTHREAD_KEYS_MAX + PTHREAD_KEY_2NDLEVEL_SIZE - 1) \
  74    / PTHREAD_KEY_2NDLEVEL_SIZE)
  75
  76 typedef void (*destr_function)(void *);
  77
  78 struct pthread_key_struct {
  79   int in_use;                   /* already allocated? */
  80   destr_function destr;         /* destruction routine */
  81 };
  82
  83
  84 #define PTHREAD_START_ARGS_INITIALIZER(fct) \
  85   { (void *(*) (void *)) fct, NULL, {{0, }}, 0, { 0 } }
  86
  87 /* The type of thread descriptors */
  88
  89 typedef struct _pthread_descr_struct * pthread_descr;
  90
  91 /* Callback interface for removing the thread from waiting on an
  92    object if it is cancelled while waiting or about to wait.
  93    This hold a pointer to the object, and a pointer to a function
  94    which ``extricates'' the thread from its enqueued state.
  95    The function takes two arguments: pointer to the wait object,
  96    and a pointer to the thread. It returns 1 if an extrication
  97    actually occured, and hence the thread must also be signalled.
  98    It returns 0 if the thread had already been extricated. */
  99
 100 typedef struct _pthread_extricate_struct {
 101     void *pu_object;
 102     int (*pu_extricate_func)(void *, pthread_descr);
 103 } pthread_extricate_if;
 104
 105 /* Atomic counter made possible by compare_and_swap */
 106
 107 struct pthread_atomic {
 108   long p_count;
 109   int p_spinlock;
 110 };
 111
 112 /* Context info for read write locks. The pthread_rwlock_info structure
 113    is information about a lock that has been read-locked by the thread
 114    in whose list this structure appears. The pthread_rwlock_context
 115    is embedded in the thread context and contains a pointer to the
 116    head of the list of lock info structures, as well as a count of
 117    read locks that are untracked, because no info structure could be
 118    allocated for them. */
 119
 120 struct _pthread_rwlock_t;
 121
 122 typedef struct _pthread_rwlock_info {
 123   struct _pthread_rwlock_info *pr_next;
 124   struct _pthread_rwlock_t *pr_lock;
 125   int pr_lock_count;
 126 } pthread_readlock_info;
 127
 128 struct _pthread_descr_struct {
 129   union {
 130     struct {
 131       pthread_descr self;       /* Pointer to this structure */
 132     } data;
 133     void *__padding[16];
 134   } p_header;
 135   pthread_descr p_nextlive, p_prevlive;
 136                                 /* Double chaining of active threads */
 137   pthread_descr p_nextwaiting;  /* Next element in the queue holding the thr */
 138   pthread_descr p_nextlock;     /* can be on a queue and waiting on a lock */
 139   pthread_t p_tid;              /* Thread identifier */
 140   int p_pid;                    /* PID of Unix process */
 141   int p_priority;               /* Thread priority (== 0 if not realtime) */
 142   struct _pthread_fastlock * p_lock; /* Spinlock for synchronized accesses */
 143   int p_signal;                 /* last signal received */
 144   sigjmp_buf * p_signal_jmp;    /* where to siglongjmp on a signal or NULL */
 145   sigjmp_buf * p_cancel_jmp;    /* where to siglongjmp on a cancel or NULL */
 146   char p_terminated;            /* true if terminated e.g. by pthread_exit */
 147   char p_detached;              /* true if detached */
 148   char p_exited;                /* true if the assoc. process terminated */
 149   void * p_retval;              /* placeholder for return value */
 150   int p_retcode;                /* placeholder for return code */
 151   pthread_descr p_joining;      /* thread joining on that thread or NULL */
 152   struct _pthread_cleanup_buffer * p_cleanup; /* cleanup functions */
 153   char p_cancelstate;           /* cancellation state */
 154   char p_canceltype;            /* cancellation type (deferred/async) */
 155   char p_canceled;              /* cancellation request pending */
 156   int * p_errnop;               /* pointer to used errno variable */
 157   int p_errno;                  /* error returned by last system call */
 158   int * p_h_errnop;             /* pointer to used h_errno variable */
 159   int p_h_errno;                /* error returned by last netdb function */
 160   char * p_in_sighandler;       /* stack address of sighandler, or NULL */
 161   char p_sigwaiting;            /* true if a sigwait() is in progress */
 162   struct pthread_start_args p_start_args; /* arguments for thread creation */
 163   void ** p_specific[PTHREAD_KEY_1STLEVEL_SIZE]; /* thread-specific data */
 164   void * p_libc_specific[_LIBC_TSD_KEY_N]; /* thread-specific data for libc */
 165   int p_userstack;              /* nonzero if the user provided the stack */
 166   void *p_guardaddr;            /* address of guard area or NULL */
 167   size_t p_guardsize;           /* size of guard area */
 168   int p_nr;                     /* Index of descriptor in __pthread_handles */
 169   int p_report_events;          /* Nonzero if events must be reported.  */
 170   td_eventbuf_t p_eventbuf;     /* Data for event.  */
 171   struct pthread_atomic p_resume_count; /* number of times restart() was
 172                                            called on thread */
 173   char p_woken_by_cancel;       /* cancellation performed wakeup */
 174   char p_condvar_avail;         /* flag if conditional variable became avail */
 175   char p_sem_avail;             /* flag if semaphore became available */
 176   pthread_extricate_if *p_extricate; /* See above */
 177   pthread_readlock_info *p_readlock_list;  /* List of readlock info structs */
 178   pthread_readlock_info *p_readlock_free;  /* Free list of structs */
 179   int p_untracked_readlock_count;       /* Readlocks not tracked by list */
 180   struct __res_state *p_resp;   /* Pointer to resolver state */
 181   struct __res_state p_res;     /* per-thread resolver state */
 182   int p_inheritsched;           /* copied from the thread attribute */
 183 #if HP_TIMING_AVAIL
 184   hp_timing_t p_cpuclock_offset; /* Initial CPU clock for thread.  */
 185 #endif
 186   /* New elements must be added at the end.  */
 187 } __attribute__ ((aligned(32))); /* We need to align the structure so that
 188                                     doubles are aligned properly.  This is 8
 189                                     bytes on MIPS and 16 bytes on MIPS64.
 190                                     32 bytes might give better cache
 191                                     utilization.  */
 192
 193
 194 /* The type of thread handles. */
 195
 196 typedef struct pthread_handle_struct * pthread_handle;
 197
 198 struct pthread_handle_struct {
 199   struct _pthread_fastlock h_lock; /* Fast lock for sychronized access */
 200   pthread_descr h_descr;        /* Thread descriptor or NULL if invalid */
 201   char * h_bottom;              /* Lowest address in the stack thread */
 202 };
 203
 204 /* The type of messages sent to the thread manager thread */
 205
 206 struct pthread_request {
 207   pthread_descr req_thread;     /* Thread doing the request */
 208   enum {                        /* Request kind */
 209     REQ_CREATE, REQ_FREE, REQ_PROCESS_EXIT, REQ_MAIN_THREAD_EXIT,
 210     REQ_POST, REQ_DEBUG, REQ_KICK
 211   } req_kind;
 212   union {                       /* Arguments for request */
 213     struct {                    /* For REQ_CREATE: */
 214       const pthread_attr_t * attr; /* thread attributes */
 215       void * (*fn)(void *);     /*   start function */
 216       void * arg;               /*   argument to start function */
 217       sigset_t mask;            /*   signal mask */
 218     } create;
 219     struct {                    /* For REQ_FREE: */
 220       pthread_t thread_id;      /*   identifier of thread to free */
 221     } free;
 222     struct {                    /* For REQ_PROCESS_EXIT: */
 223       int code;                 /*   exit status */
 224     } exit;
 225     void * post;                /* For REQ_POST: the semaphore */
 226   } req_args;
 227 };
 228
 229
 230 /* Signals used for suspend/restart and for cancellation notification.  */
 231
 232 extern int __pthread_sig_restart;
 233 extern int __pthread_sig_cancel;
 234
 235 /* Signal used for interfacing with gdb */
 236
 237 extern int __pthread_sig_debug;
 238
 239 /* Global array of thread handles, used for validating a thread id
 240    and retrieving the corresponding thread descriptor. Also used for
 241    mapping the available stack segments. */
 242
 243 extern struct pthread_handle_struct __pthread_handles[PTHREAD_THREADS_MAX];
 244
 245 /* Descriptor of the initial thread */
 246
 247 extern struct _pthread_descr_struct __pthread_initial_thread;
 248
 249 /* Descriptor of the manager thread */
 250
 251 extern struct _pthread_descr_struct __pthread_manager_thread;
 252
 253 /* Descriptor of the main thread */
 254
 255 extern pthread_descr __pthread_main_thread;
 256
 257 /* Limit between the stack of the initial thread (above) and the
 258    stacks of other threads (below). Aligned on a STACK_SIZE boundary.
 259    Initially 0, meaning that the current thread is (by definition)
 260    the initial thread. */
 261
 262 extern char *__pthread_initial_thread_bos;
 263
 264 /* Indicate whether at least one thread has a user-defined stack (if 1),
 265    or all threads have stacks supplied by LinuxThreads (if 0). */
 266
 267 extern int __pthread_nonstandard_stacks;
 268
 269 /* File descriptor for sending requests to the thread manager.
 270    Initially -1, meaning that __pthread_initialize_manager must be called. */
 271
 272 extern int __pthread_manager_request;
 273
 274 /* Other end of the pipe for sending requests to the thread manager. */
 275
 276 extern int __pthread_manager_reader;
 277
 278 /* Limits of the thread manager stack. */
 279
 280 extern char *__pthread_manager_thread_bos;
 281 extern char *__pthread_manager_thread_tos;
 282
 283 #ifdef FLOATING_STACKS
 284 /* Maximum stack size.  */
 285 extern size_t __pthread_max_stacksize;
 286 #endif
 287
 288 /* Pending request for a process-wide exit */
 289
 290 extern int __pthread_exit_requested, __pthread_exit_code;
 291
 292 /* Set to 1 by gdb if we're debugging */
 293
 294 extern volatile int __pthread_threads_debug;
 295
 296 /* Globally enabled events.  */
 297 extern volatile td_thr_events_t __pthread_threads_events;
 298
 299 /* Pointer to descriptor of thread with last event.  */
 300 extern volatile pthread_descr __pthread_last_event;
 301
 302 /* Flag which tells whether we are executing on SMP kernel. */
 303 extern int __pthread_smp_kernel;
 304
 305 /* Return the handle corresponding to a thread id */
 306
 307 static inline pthread_handle thread_handle(pthread_t id)
 308 {
 309   return &__pthread_handles[id % PTHREAD_THREADS_MAX];
 310 }
 311
 312 /* Validate a thread handle. Must have acquired h->h_spinlock before. */
 313
 314 static inline int invalid_handle(pthread_handle h, pthread_t id)
 315 {
 316   return h->h_descr == NULL || h->h_descr->p_tid != id || h->h_descr->p_terminated;
 317 }
 318
 319 static inline int nonexisting_handle(pthread_handle h, pthread_t id)
 320 {
 321   return h->h_descr == NULL || h->h_descr->p_tid != id;
 322 }
 323
 324 /* Fill in defaults left unspecified by pt-machine.h.  */
 325
 326 /* We round up a value with page size. */
 327 #ifndef page_roundup
 328 #define page_roundup(v,p) ((((size_t) (v)) + (p) - 1) & ~((p) - 1))
 329 #endif
 330
 331 /* The page size we can get from the system.  This should likely not be
 332    changed by the machine file but, you never know.  */
 333 #ifndef PAGE_SIZE
 334 #define PAGE_SIZE  (sysconf (_SC_PAGE_SIZE))
 335 #endif
 336
 337 /* The max size of the thread stack segments.  If the default
 338    THREAD_SELF implementation is used, this must be a power of two and
 339    a multiple of PAGE_SIZE.  */
 340 #ifndef STACK_SIZE
 341 #define STACK_SIZE  (2 * 1024 * 1024)
 342 #endif
 343
 344 /* The initial size of the thread stack.  Must be a multiple of PAGE_SIZE.  */
 345 #ifndef INITIAL_STACK_SIZE
 346 #define INITIAL_STACK_SIZE  (4 * PAGE_SIZE)
 347 #endif
 348
 349 /* Size of the thread manager stack. The "- 32" avoids wasting space
 350    with some malloc() implementations. */
 351 #ifndef THREAD_MANAGER_STACK_SIZE
 352 #define THREAD_MANAGER_STACK_SIZE  (2 * PAGE_SIZE - 32)
 353 #endif
 354
 355 /* The base of the "array" of thread stacks.  The array will grow down from
 356    here.  Defaults to the calculated bottom of the initial application
 357    stack.  */
 358 #ifndef THREAD_STACK_START_ADDRESS
 359 #define THREAD_STACK_START_ADDRESS  __pthread_initial_thread_bos
 360 #endif
 361
 362 /* Get some notion of the current stack.  Need not be exactly the top
 363    of the stack, just something somewhere in the current frame.  */
 364 #ifndef CURRENT_STACK_FRAME
 365 #define CURRENT_STACK_FRAME  ({ char __csf; &__csf; })
 366 #endif
 367
 368 /* Recover thread descriptor for the current thread */
 369
 370 extern pthread_descr __pthread_find_self (void) __attribute__ ((const));
 371
 372 static inline pthread_descr thread_self (void) __attribute__ ((const));
 373 static inline pthread_descr thread_self (void)
 374 {
 375 #ifdef THREAD_SELF
 376   return THREAD_SELF;
 377 #else
 378   char *sp = CURRENT_STACK_FRAME;
 379   if (sp >= __pthread_initial_thread_bos)
 380     return &__pthread_initial_thread;
 381   else if (sp >= __pthread_manager_thread_bos
 382            && sp < __pthread_manager_thread_tos)
 383     return &__pthread_manager_thread;
 384   else if (__pthread_nonstandard_stacks)
 385     return __pthread_find_self();
 386   else
 387     return (pthread_descr)(((unsigned long)sp | (STACK_SIZE-1))+1) - 1;
 388 #endif
 389 }
 390
 391 /* If MEMORY_BARRIER isn't defined in pt-machine.h, assume the architecture
 392    doesn't need a memory barrier instruction (e.g. Intel x86).  Some
 393    architectures distinguish between full, read and write barriers.  */
 394
 395 #ifndef MEMORY_BARRIER
 396 #define MEMORY_BARRIER()
 397 #endif
 398 #ifndef READ_MEMORY_BARRIER
 399 #define READ_MEMORY_BARRIER() MEMORY_BARRIER()
 400 #endif
 401 #ifndef WRITE_MEMORY_BARRIER
 402 #define WRITE_MEMORY_BARRIER() MEMORY_BARRIER()
 403 #endif
 404
 405 /* Max number of times we must spin on a spinlock calling sched_yield().
 406    After MAX_SPIN_COUNT iterations, we put the calling thread to sleep. */
 407
 408 #ifndef MAX_SPIN_COUNT
 409 #define MAX_SPIN_COUNT 50
 410 #endif
 411
 412 /* Duration of sleep (in nanoseconds) when we can't acquire a spinlock
 413    after MAX_SPIN_COUNT iterations of sched_yield().
 414    With the 2.0 and 2.1 kernels, this MUST BE > 2ms.
 415    (Otherwise the kernel does busy-waiting for realtime threads,
 416     giving other threads no chance to run.) */
 417
 418 #ifndef SPIN_SLEEP_DURATION
 419 #define SPIN_SLEEP_DURATION 2000001
 420 #endif
 421
 422 /* Debugging */
 423
 424 #ifdef DEBUG
 425 #include <assert.h>
 426 #define ASSERT assert
 427 #define MSG __pthread_message
 428 #else
 429 #define ASSERT(x)
 430 #define MSG(msg,arg...)
 431 #endif
 432
 433 /* Internal global functions */
 434
 435 extern void __pthread_do_exit (void *retval, char *currentframe)
 436      __attribute__ ((__noreturn__));
 437 extern void __pthread_destroy_specifics (void);
 438 extern void __pthread_perform_cleanup (char *currentframe);
 439 extern void __pthread_init_max_stacksize (void);
 440 extern int __pthread_initialize_manager (void);
 441 extern void __pthread_message (char * fmt, ...);
 442 extern int __pthread_manager (void *reqfd);
 443 extern int __pthread_manager_event (void *reqfd);
 444 extern void __pthread_manager_sighandler (int sig);
 445 extern void __pthread_reset_main_thread (void);
 446 extern void __pthread_once_fork_prepare (void);
 447 extern void __pthread_once_fork_parent (void);
 448 extern void __pthread_once_fork_child (void);
 449 extern void __flockfilelist (void);
 450 extern void __funlockfilelist (void);
 451 extern void __fresetlockfiles (void);
 452 extern void __pthread_manager_adjust_prio (int thread_prio);
 453 extern void __pthread_initialize_minimal (void);
 454
 455 extern int __pthread_attr_setguardsize (pthread_attr_t *__attr,
 456                                         size_t __guardsize);
 457 extern int __pthread_attr_getguardsize (const pthread_attr_t *__attr,
 458                                         size_t *__guardsize);
 459 extern int __pthread_attr_setstackaddr (pthread_attr_t *__attr,
 460                                         void *__stackaddr);
 461 extern int __pthread_attr_getstackaddr (const pthread_attr_t *__attr,
 462                                         void **__stackaddr);
 463 extern int __pthread_attr_setstacksize (pthread_attr_t *__attr,
 464                                         size_t __stacksize);
 465 extern int __pthread_attr_getstacksize (const pthread_attr_t *__attr,
 466                                         size_t *__stacksize);
 467 extern int __pthread_attr_setstack (pthread_attr_t *__attr, void *__stackaddr,
 468                                     size_t __stacksize);
 469 extern int __pthread_attr_getstack (const pthread_attr_t *__attr, void **__stackaddr,
 470                                     size_t *__stacksize);
 471 extern int __pthread_getconcurrency (void);
 472 extern int __pthread_setconcurrency (int __level);
 473 extern int __pthread_mutex_timedlock (pthread_mutex_t *__mutex,
 474                                       const struct timespec *__abstime);
 475 extern int __pthread_mutexattr_getpshared (const pthread_mutexattr_t *__attr,
 476                                            int *__pshared);
 477 extern int __pthread_mutexattr_setpshared (pthread_mutexattr_t *__attr,
 478                                            int __pshared);
 479 extern int __pthread_mutexattr_gettype (const pthread_mutexattr_t *__attr,
 480                                         int *__kind);
 481 extern void __pthread_kill_other_threads_np (void);
 482
 483 extern void __pthread_restart_old(pthread_descr th);
 484 extern void __pthread_suspend_old(pthread_descr self);
 485 extern int __pthread_timedsuspend_old(pthread_descr self, const struct timespec *abs);
 486
 487 extern void __pthread_restart_new(pthread_descr th);
 488 extern void __pthread_suspend_new(pthread_descr self);
 489 extern int __pthread_timedsuspend_new(pthread_descr self, const struct timespec *abs);
 490
 491 extern void __pthread_wait_for_restart_signal(pthread_descr self);
 492
 493 extern int __pthread_yield (void);
 494
 495 extern int __pthread_rwlock_timedrdlock (pthread_rwlock_t *__restrict __rwlock,
 496                                          __const struct timespec *__restrict
 497                                          __abstime);
 498 extern int __pthread_rwlock_timedwrlock (pthread_rwlock_t *__restrict __rwlock,
 499                                          __const struct timespec *__restrict
 500                                          __abstime);
 501 extern int __pthread_rwlockattr_destroy (pthread_rwlockattr_t *__attr);
 502
 503 extern int __pthread_barrierattr_getpshared (__const pthread_barrierattr_t *
 504                                              __restrict __attr,
 505                                              int *__restrict __pshared);
 506
 507 extern int __pthread_spin_lock (pthread_spinlock_t *__lock);
 508 extern int __pthread_spin_trylock (pthread_spinlock_t *__lock);
 509 extern int __pthread_spin_unlock (pthread_spinlock_t *__lock);
 510 extern int __pthread_spin_init (pthread_spinlock_t *__lock, int __pshared);
 511 extern int __pthread_spin_destroy (pthread_spinlock_t *__lock);
 512
 513 extern int __pthread_clock_gettime (hp_timing_t freq, struct timespec *tp);
 514 extern void __pthread_clock_settime (hp_timing_t offset);
 515
 516
 517 /* Global pointers to old or new suspend functions */
 518
 519 extern void (*__pthread_restart)(pthread_descr);
 520 extern void (*__pthread_suspend)(pthread_descr);
 521 extern int (*__pthread_timedsuspend)(pthread_descr, const struct timespec *);
 522
 523 /* Prototypes for the function without cancelation support when the
 524    normal version has it.  */
 525 extern int __libc_close (int fd);
 526 extern int __libc_nanosleep (const struct timespec *requested_time,
 527                              struct timespec *remaining);
 528 /* Prototypes for some of the new semaphore functions.  */
 529 extern int __new_sem_post (sem_t * sem);
 530 extern int __new_sem_init (sem_t *__sem, int __pshared, unsigned int __value);
 531 extern int __new_sem_wait (sem_t *__sem);
 532 extern int __new_sem_trywait (sem_t *__sem);
 533 extern int __new_sem_getvalue (sem_t *__restrict __sem, int *__restrict __sval);
 534 extern int __new_sem_destroy (sem_t *__sem);
 535
 536 /* Prototypes for compatibility functions.  */
 537 extern int __pthread_attr_init_2_1 (pthread_attr_t *__attr);
 538 extern int __pthread_attr_init_2_0 (pthread_attr_t *__attr);
 539 extern int __pthread_create_2_1 (pthread_t *__restrict __thread,
 540                                  const pthread_attr_t *__attr,
 541                                  void *(*__start_routine) (void *),
 542                                  void *__restrict __arg);
 543 extern int __pthread_create_2_0 (pthread_t *__restrict thread,
 544                                  const pthread_attr_t *__attr,
 545                                  void *(*__start_routine) (void *),
 546                                  void *__restrict arg);
 547
 548 /* The functions called the signal events.  */
 549 extern void __linuxthreads_create_event (void);
 550 extern void __linuxthreads_death_event (void);
 551 extern void __linuxthreads_reap_event (void);
 552
 553 /* This function is called to initialize the pthread library.  */
 554 extern void __pthread_initialize (void);
 555
 556 #endif /* internals.h */