thread.h

   1 /*    thread.h
   2  *
   3  *    Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
   4  *    by Larry Wall and others
   5  *
   6  *    You may distribute under the terms of either the GNU General Public
   7  *    License or the Artistic License, as specified in the README file.
   8  *
   9  */
  10
  11 #if defined(USE_5005THREADS) || defined(USE_ITHREADS)
  12
  13 #if defined(VMS)
  14 #include <builtins.h>
  15 #endif
  16
  17 #ifdef WIN32
  18 #  include <win32thread.h>
  19 #else
  20 #ifdef NETWARE
  21 #  include <nw5thread.h>
  22 #else
  23 #  ifdef OLD_PTHREADS_API /* Here be dragons. */
  24 #    define DETACH(t) \
  25     STMT_START {                                                \
  26         int _eC_;                                               \
  27         if ((_eC_ = pthread_detach(&(t)->self))) {              \
  28             MUTEX_UNLOCK(&(t)->mutex);                          \
  29             Perl_croak_nocontext("panic: DETACH (%d) [%s:%d]",  \
  30                                  _eC_, __FILE__, __LINE__);     \
  31         }                                                       \
  32     } STMT_END
  33
  34 #    define PERL_GET_CONTEXT    Perl_get_context()
  35 #    define PERL_SET_CONTEXT(t) Perl_set_context((void*)t)
  36
  37 #    define PTHREAD_GETSPECIFIC_INT
  38 #    ifdef DJGPP
  39 #      define pthread_addr_t any_t
  40 #      define NEED_PTHREAD_INIT
  41 #      define PTHREAD_CREATE_JOINABLE (1)
  42 #    endif
  43 #    ifdef __OPEN_VM
  44 #      define pthread_addr_t void *
  45 #    endif
  46 #    ifdef OEMVS
  47 #      define pthread_addr_t void *
  48 #      define pthread_create(t,a,s,d)        pthread_create(t,&(a),s,d)
  49 #      define pthread_keycreate              pthread_key_create
  50 #    endif
  51 #    ifdef VMS
  52 #      define pthread_attr_init(a) pthread_attr_create(a)
  53 #      define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_setdetach_np(a,s)
  54 #      define PTHREAD_CREATE(t,a,s,d) pthread_create(t,a,s,d)
  55 #      define pthread_key_create(k,d) pthread_keycreate(k,(pthread_destructor_t)(d))
  56 #      define pthread_mutexattr_init(a) pthread_mutexattr_create(a)
  57 #      define pthread_mutexattr_settype(a,t) pthread_mutexattr_setkind_np(a,t)
  58 #    endif
  59 #    if defined(__hpux) && defined(__ux_version) && __ux_version <= 1020
  60 #      define pthread_attr_init(a) pthread_attr_create(a)
  61        /* XXX pthread_setdetach_np() missing in DCE threads on HP-UX 10.20 */
  62 #      define PTHREAD_ATTR_SETDETACHSTATE(a,s)  (0)
  63 #      define PTHREAD_CREATE(t,a,s,d) pthread_create(t,a,s,d)
  64 #      define pthread_key_create(k,d) pthread_keycreate(k,(pthread_destructor_t)(d))
  65 #      define pthread_mutexattr_init(a) pthread_mutexattr_create(a)
  66 #      define pthread_mutexattr_settype(a,t) pthread_mutexattr_setkind_np(a,t)
  67 #    endif
  68 #    if defined(DJGPP) || defined(__OPEN_VM) || defined(OEMVS)
  69 #      define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_attr_setdetachstate(a,&(s))
  70 #      define YIELD pthread_yield(NULL)
  71 #    endif
  72 #  endif
  73 #  if !defined(__hpux) || !defined(__ux_version) || __ux_version > 1020
  74 #    define pthread_mutexattr_default NULL
  75 #    define pthread_condattr_default  NULL
  76 #  endif
  77 #endif  /* NETWARE */
  78 #endif
  79
  80 #ifndef PTHREAD_CREATE
  81 /* You are not supposed to pass NULL as the 2nd arg of PTHREAD_CREATE(). */
  82 #  define PTHREAD_CREATE(t,a,s,d) pthread_create(t,&(a),s,d)
  83 #endif
  84
  85 #ifndef PTHREAD_ATTR_SETDETACHSTATE
  86 #  define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_attr_setdetachstate(a,s)
  87 #endif
  88
  89 #ifndef PTHREAD_CREATE_JOINABLE
  90 #  ifdef OLD_PTHREAD_CREATE_JOINABLE
  91 #    define PTHREAD_CREATE_JOINABLE OLD_PTHREAD_CREATE_JOINABLE
  92 #  else
  93 #    define PTHREAD_CREATE_JOINABLE 0 /* Panic?  No, guess. */
  94 #  endif
  95 #endif
  96
  97 #ifdef DGUX
  98 #  define THREAD_CREATE_NEEDS_STACK (32*1024)
  99 #endif
 100
 101 #ifdef I_MACH_CTHREADS
 102
 103 /* cthreads interface */
 104
 105 /* #include <mach/cthreads.h> is in perl.h #ifdef I_MACH_CTHREADS */
 106
 107 #define MUTEX_INIT(m) \
 108     STMT_START {                                                \
 109         *m = mutex_alloc();                                     \
 110         if (*m) {                                               \
 111             mutex_init(*m);                                     \
 112         } else {                                                \
 113             Perl_croak_nocontext("panic: MUTEX_INIT [%s:%d]",   \
 114                                  __FILE__, __LINE__);           \
 115         }                                                       \
 116     } STMT_END
 117
 118 #define MUTEX_LOCK(m)                   mutex_lock(*m)
 119 #define MUTEX_UNLOCK(m)                 mutex_unlock(*m)
 120 #define MUTEX_DESTROY(m) \
 121     STMT_START {                                                \
 122         mutex_free(*m);                                         \
 123         *m = 0;                                                 \
 124     } STMT_END
 125
 126 #define COND_INIT(c) \
 127     STMT_START {                                                \
 128         *c = condition_alloc();                                 \
 129         if (*c) {                                               \
 130             condition_init(*c);                                 \
 131         }                                                       \
 132         else {                                                  \
 133             Perl_croak_nocontext("panic: COND_INIT [%s:%d]",    \
 134                                  __FILE__, __LINE__);           \
 135         }                                                       \
 136     } STMT_END
 137
 138 #define COND_SIGNAL(c)          condition_signal(*c)
 139 #define COND_BROADCAST(c)       condition_broadcast(*c)
 140 #define COND_WAIT(c, m)         condition_wait(*c, *m)
 141 #define COND_DESTROY(c) \
 142     STMT_START {                                                \
 143         condition_free(*c);                                     \
 144         *c = 0;                                                 \
 145     } STMT_END
 146
 147 #define THREAD_CREATE(thr, f)   (thr->self = cthread_fork(f, thr), 0)
 148 #define THREAD_POST_CREATE(thr)
 149
 150 #define THREAD_RET_TYPE         any_t
 151 #define THREAD_RET_CAST(x)      ((any_t) x)
 152
 153 #define DETACH(t)               cthread_detach(t->self)
 154 #define JOIN(t, avp)            (*(avp) = (AV *)cthread_join(t->self))
 155
 156 #define PERL_SET_CONTEXT(t)     cthread_set_data(cthread_self(), t)
 157 #define PERL_GET_CONTEXT        cthread_data(cthread_self())
 158
 159 #define INIT_THREADS            cthread_init()
 160 #define YIELD                   cthread_yield()
 161 #define ALLOC_THREAD_KEY        NOOP
 162 #define FREE_THREAD_KEY         NOOP
 163 #define SET_THREAD_SELF(thr)    (thr->self = cthread_self())
 164
 165 #endif /* I_MACH_CTHREADS */
 166
 167 #ifndef YIELD
 168 #  ifdef SCHED_YIELD
 169 #    define YIELD SCHED_YIELD
 170 #  else
 171 #    ifdef HAS_SCHED_YIELD
 172 #      define YIELD sched_yield()
 173 #    else
 174 #      ifdef HAS_PTHREAD_YIELD
 175     /* pthread_yield(NULL) platforms are expected
 176      * to have #defined YIELD for themselves. */
 177 #        define YIELD pthread_yield()
 178 #      endif
 179 #    endif
 180 #  endif
 181 #endif
 182
 183 #ifdef __hpux
 184 #  define MUTEX_INIT_NEEDS_MUTEX_ZEROED
 185 #endif
 186
 187 #ifndef MUTEX_INIT
 188
 189 #  ifdef MUTEX_INIT_NEEDS_MUTEX_ZEROED
 190     /* Temporary workaround, true bug is deeper. --jhi 1999-02-25 */
 191 #    define MUTEX_INIT(m) \
 192     STMT_START {                                                \
 193         int _eC_;                                               \
 194         Zero((m), 1, perl_mutex);                               \
 195         if ((_eC_ = pthread_mutex_init((m), pthread_mutexattr_default)))        \
 196             Perl_croak_nocontext("panic: MUTEX_INIT (%d) [%s:%d]",      \
 197                                  _eC_, __FILE__, __LINE__);     \
 198     } STMT_END
 199 #  else
 200 #    define MUTEX_INIT(m) \
 201     STMT_START {                                                \
 202         int _eC_;                                               \
 203         if ((_eC_ = pthread_mutex_init((m), pthread_mutexattr_default)))        \
 204             Perl_croak_nocontext("panic: MUTEX_INIT (%d) [%s:%d]",      \
 205                                  _eC_, __FILE__, __LINE__);     \
 206     } STMT_END
 207 #  endif
 208
 209 #  define MUTEX_LOCK(m) \
 210     STMT_START {                                                \
 211         int _eC_;                                               \
 212         if ((_eC_ = pthread_mutex_lock((m))))                   \
 213             Perl_croak_nocontext("panic: MUTEX_LOCK (%d) [%s:%d]",      \
 214                                  _eC_, __FILE__, __LINE__);     \
 215     } STMT_END
 216
 217 #  define MUTEX_UNLOCK(m) \
 218     STMT_START {                                                \
 219         int _eC_;                                               \
 220         if ((_eC_ = pthread_mutex_unlock((m))))                 \
 221             Perl_croak_nocontext("panic: MUTEX_UNLOCK (%d) [%s:%d]",    \
 222                                  _eC_, __FILE__, __LINE__);     \
 223     } STMT_END
 224
 225 #  define MUTEX_DESTROY(m) \
 226     STMT_START {                                                \
 227         int _eC_;                                               \
 228         if ((_eC_ = pthread_mutex_destroy((m))))                \
 229             Perl_croak_nocontext("panic: MUTEX_DESTROY (%d) [%s:%d]",   \
 230                                  _eC_, __FILE__, __LINE__);     \
 231     } STMT_END
 232 #endif /* MUTEX_INIT */
 233
 234 #ifndef COND_INIT
 235 #  define COND_INIT(c) \
 236     STMT_START {                                                \
 237         int _eC_;                                               \
 238         if ((_eC_ = pthread_cond_init((c), pthread_condattr_default)))  \
 239             Perl_croak_nocontext("panic: COND_INIT (%d) [%s:%d]",       \
 240                                  _eC_, __FILE__, __LINE__);     \
 241     } STMT_END
 242
 243 #  define COND_SIGNAL(c) \
 244     STMT_START {                                                \
 245         int _eC_;                                               \
 246         if ((_eC_ = pthread_cond_signal((c))))                  \
 247             Perl_croak_nocontext("panic: COND_SIGNAL (%d) [%s:%d]",     \
 248                                  _eC_, __FILE__, __LINE__);     \
 249     } STMT_END
 250
 251 #  define COND_BROADCAST(c) \
 252     STMT_START {                                                \
 253         int _eC_;                                               \
 254         if ((_eC_ = pthread_cond_broadcast((c))))               \
 255             Perl_croak_nocontext("panic: COND_BROADCAST (%d) [%s:%d]",  \
 256                                  _eC_, __FILE__, __LINE__);     \
 257     } STMT_END
 258
 259 #  define COND_WAIT(c, m) \
 260     STMT_START {                                                \
 261         int _eC_;                                               \
 262         if ((_eC_ = pthread_cond_wait((c), (m))))               \
 263             Perl_croak_nocontext("panic: COND_WAIT (%d) [%s:%d]",       \
 264                                  _eC_, __FILE__, __LINE__);     \
 265     } STMT_END
 266
 267 #  define COND_DESTROY(c) \
 268     STMT_START {                                                \
 269         int _eC_;                                               \
 270         if ((_eC_ = pthread_cond_destroy((c))))                 \
 271             Perl_croak_nocontext("panic: COND_DESTROY (%d) [%s:%d]",    \
 272                                  _eC_, __FILE__, __LINE__);     \
 273     } STMT_END
 274 #endif /* COND_INIT */
 275
 276 /* DETACH(t) must only be called while holding t->mutex */
 277 #ifndef DETACH
 278 #  define DETACH(t) \
 279     STMT_START {                                                \
 280         int _eC_;                                               \
 281         if ((_eC_ = pthread_detach((t)->self))) {               \
 282             MUTEX_UNLOCK(&(t)->mutex);                          \
 283             Perl_croak_nocontext("panic: DETACH (%d) [%s:%d]",  \
 284                                  _eC_, __FILE__, __LINE__);     \
 285         }                                                       \
 286     } STMT_END
 287 #endif /* DETACH */
 288
 289 #ifndef JOIN
 290 #  define JOIN(t, avp) \
 291     STMT_START {                                                \
 292         int _eC_;                                               \
 293         if ((_eC_ = pthread_join((t)->self, (void**)(avp))))    \
 294             Perl_croak_nocontext("panic: pthread_join (%d) [%s:%d]",    \
 295                                  _eC_, __FILE__, __LINE__);     \
 296     } STMT_END
 297 #endif /* JOIN */
 298
 299 /* Use an unchecked fetch of thread-specific data instead of a checked one.
 300  * It would fail if the key were bogus, but if the key were bogus then
 301  * Really Bad Things would be happening anyway. --dan */
 302 #if (defined(__ALPHA) && (__VMS_VER >= 70000000)) || \
 303     (defined(__alpha) && defined(__osf__) && !defined(__GNUC__)) /* Available only on >= 4.0 */
 304 #  define HAS_PTHREAD_UNCHECKED_GETSPECIFIC_NP /* Configure test needed */
 305 #endif
 306
 307 #ifdef HAS_PTHREAD_UNCHECKED_GETSPECIFIC_NP
 308 #  define PTHREAD_GETSPECIFIC(key) pthread_unchecked_getspecific_np(key)
 309 #else
 310 #    define PTHREAD_GETSPECIFIC(key) pthread_getspecific(key)
 311 #endif
 312
 313 #ifndef PERL_GET_CONTEXT
 314 #  define PERL_GET_CONTEXT      PTHREAD_GETSPECIFIC(PL_thr_key)
 315 #endif
 316
 317 #ifndef PERL_SET_CONTEXT
 318 #  define PERL_SET_CONTEXT(t) \
 319     STMT_START {                                                \
 320         int _eC_;                                               \
 321         if ((_eC_ = pthread_setspecific(PL_thr_key, (void *)(t))))      \
 322             Perl_croak_nocontext("panic: pthread_setspecific (%d) [%s:%d]",     \
 323                                  _eC_, __FILE__, __LINE__);     \
 324     } STMT_END
 325 #endif /* PERL_SET_CONTEXT */
 326
 327 #ifndef INIT_THREADS
 328 #  ifdef NEED_PTHREAD_INIT
 329 #    define INIT_THREADS pthread_init()
 330 #  endif
 331 #endif
 332
 333 #ifndef ALLOC_THREAD_KEY
 334 #  define ALLOC_THREAD_KEY \
 335     STMT_START {                                                \
 336         if (pthread_key_create(&PL_thr_key, 0)) {               \
 337             write(2, STR_WITH_LEN("panic: pthread_key_create failed\n")); \
 338             exit(1);                                            \
 339         }                                                       \
 340     } STMT_END
 341 #endif
 342
 343 #ifndef FREE_THREAD_KEY
 344 #  define FREE_THREAD_KEY \
 345     STMT_START {                                                \
 346         pthread_key_delete(PL_thr_key);                         \
 347     } STMT_END
 348 #endif
 349
 350 #ifndef PTHREAD_ATFORK
 351 #  ifdef HAS_PTHREAD_ATFORK
 352 #    define PTHREAD_ATFORK(prepare,parent,child)                \
 353         pthread_atfork(prepare,parent,child)
 354 #  else
 355 #    define PTHREAD_ATFORK(prepare,parent,child)                \
 356         NOOP
 357 #  endif
 358 #endif
 359
 360 #ifndef THREAD_RET_TYPE
 361 #  define THREAD_RET_TYPE       void *
 362 #  define THREAD_RET_CAST(p)    ((void *)(p))
 363 #endif /* THREAD_RET */
 364
 365 #if defined(USE_5005THREADS)
 366
 367 /* Accessor for per-thread SVs */
 368 #  define THREADSV(i) (thr->threadsvp[i])
 369
 370 /*
 371  * LOCK_SV_MUTEX and UNLOCK_SV_MUTEX are performance-critical. Here, we
 372  * try only locking them if there may be more than one thread in existence.
 373  * Systems with very fast mutexes (and/or slow conditionals) may wish to
 374  * remove the "if (threadnum) ..." test.
 375  * XXX do NOT use C<if (PL_threadnum) ...> -- it sets up race conditions!
 376  */
 377 #  define LOCK_SV_MUTEX         MUTEX_LOCK(&PL_sv_mutex)
 378 #  define UNLOCK_SV_MUTEX       MUTEX_UNLOCK(&PL_sv_mutex)
 379 #  define LOCK_STRTAB_MUTEX     MUTEX_LOCK(&PL_strtab_mutex)
 380 #  define UNLOCK_STRTAB_MUTEX   MUTEX_UNLOCK(&PL_strtab_mutex)
 381 #  define LOCK_CRED_MUTEX       MUTEX_LOCK(&PL_cred_mutex)
 382 #  define UNLOCK_CRED_MUTEX     MUTEX_UNLOCK(&PL_cred_mutex)
 383 #  define LOCK_FDPID_MUTEX      MUTEX_LOCK(&PL_fdpid_mutex)
 384 #  define UNLOCK_FDPID_MUTEX    MUTEX_UNLOCK(&PL_fdpid_mutex)
 385 #  define LOCK_SV_LOCK_MUTEX    MUTEX_LOCK(&PL_sv_lock_mutex)
 386 #  define UNLOCK_SV_LOCK_MUTEX  MUTEX_UNLOCK(&PL_sv_lock_mutex)
 387
 388 /* Values and macros for thr->flags */
 389 #define THRf_STATE_MASK 7
 390 #define THRf_R_JOINABLE 0
 391 #define THRf_R_JOINED   1
 392 #define THRf_R_DETACHED 2
 393 #define THRf_ZOMBIE     3
 394 #define THRf_DEAD       4
 395
 396 #define THRf_DID_DIE    8
 397
 398 /* ThrSTATE(t) and ThrSETSTATE(t) must only be called while holding t->mutex */
 399 #define ThrSTATE(t) ((t)->flags & THRf_STATE_MASK)
 400 #define ThrSETSTATE(t, s) STMT_START {          \
 401         (t)->flags &= ~THRf_STATE_MASK;         \
 402         (t)->flags |= (s);                      \
 403         DEBUG_S(PerlIO_printf(Perl_debug_log,   \
 404                               "thread %p set to state %d\n", (t), (s))); \
 405     } STMT_END
 406
 407 typedef struct condpair {
 408     perl_mutex  mutex;          /* Protects all other fields */
 409     perl_cond   owner_cond;     /* For when owner changes at all */
 410     perl_cond   cond;           /* For cond_signal and cond_broadcast */
 411     Thread      owner;          /* Currently owning thread */
 412 } condpair_t;
 413
 414 #define MgMUTEXP(mg) (&((condpair_t *)(mg->mg_ptr))->mutex)
 415 #define MgOWNERCONDP(mg) (&((condpair_t *)(mg->mg_ptr))->owner_cond)
 416 #define MgCONDP(mg) (&((condpair_t *)(mg->mg_ptr))->cond)
 417 #define MgOWNER(mg) ((condpair_t *)(mg->mg_ptr))->owner
 418
 419 #endif /* USE_5005THREADS */
 420
 421 #  define LOCK_DOLLARZERO_MUTEX         MUTEX_LOCK(&PL_dollarzero_mutex)
 422 #  define UNLOCK_DOLLARZERO_MUTEX       MUTEX_UNLOCK(&PL_dollarzero_mutex)
 423
 424 #endif /* USE_5005THREADS || USE_ITHREADS */
 425
 426 #ifndef MUTEX_LOCK
 427 #  define MUTEX_LOCK(m)
 428 #endif
 429
 430 #ifndef MUTEX_UNLOCK
 431 #  define MUTEX_UNLOCK(m)
 432 #endif
 433
 434 #ifndef MUTEX_INIT
 435 #  define MUTEX_INIT(m)
 436 #endif
 437
 438 #ifndef MUTEX_DESTROY
 439 #  define MUTEX_DESTROY(m)
 440 #endif
 441
 442 #ifndef COND_INIT
 443 #  define COND_INIT(c)
 444 #endif
 445
 446 #ifndef COND_SIGNAL
 447 #  define COND_SIGNAL(c)
 448 #endif
 449
 450 #ifndef COND_BROADCAST
 451 #  define COND_BROADCAST(c)
 452 #endif
 453
 454 #ifndef COND_WAIT
 455 #  define COND_WAIT(c, m)
 456 #endif
 457
 458 #ifndef COND_DESTROY
 459 #  define COND_DESTROY(c)
 460 #endif
 461
 462 #ifndef LOCK_SV_MUTEX
 463 #  define LOCK_SV_MUTEX
 464 #endif
 465
 466 #ifndef UNLOCK_SV_MUTEX
 467 #  define UNLOCK_SV_MUTEX
 468 #endif
 469
 470 #ifndef LOCK_STRTAB_MUTEX
 471 #  define LOCK_STRTAB_MUTEX
 472 #endif
 473
 474 #ifndef UNLOCK_STRTAB_MUTEX
 475 #  define UNLOCK_STRTAB_MUTEX
 476 #endif
 477
 478 #ifndef LOCK_CRED_MUTEX
 479 #  define LOCK_CRED_MUTEX
 480 #endif
 481
 482 #ifndef UNLOCK_CRED_MUTEX
 483 #  define UNLOCK_CRED_MUTEX
 484 #endif
 485
 486 #ifndef LOCK_FDPID_MUTEX
 487 #  define LOCK_FDPID_MUTEX
 488 #endif
 489
 490 #ifndef UNLOCK_FDPID_MUTEX
 491 #  define UNLOCK_FDPID_MUTEX
 492 #endif
 493
 494 #ifndef LOCK_SV_LOCK_MUTEX
 495 #  define LOCK_SV_LOCK_MUTEX
 496 #endif
 497
 498 #ifndef UNLOCK_SV_LOCK_MUTEX
 499 #  define UNLOCK_SV_LOCK_MUTEX
 500 #endif
 501
 502 #ifndef LOCK_DOLLARZERO_MUTEX
 503 #  define LOCK_DOLLARZERO_MUTEX
 504 #endif
 505
 506 #ifndef UNLOCK_DOLLARZERO_MUTEX
 507 #  define UNLOCK_DOLLARZERO_MUTEX
 508 #endif
 509
 510 /* THR, SET_THR, and dTHR are there for compatibility with old versions */
 511 #ifndef THR
 512 #  define THR           PERL_GET_THX
 513 #endif
 514
 515 #ifndef SET_THR
 516 #  define SET_THR(t)    PERL_SET_THX(t)
 517 #endif
 518
 519 #ifndef dTHR
 520 #  define dTHR dNOOP
 521 #endif
 522
 523 #ifndef INIT_THREADS
 524 #  define INIT_THREADS NOOP
 525 #endif