thread.h

   1 /*    thread.h
   2  *
   3  *    Copyright (c) 1997-2002, Larry Wall
   4  *
   5  *    You may distribute under the terms of either the GNU General Public
   6  *    License or the Artistic License, as specified in the README file.
   7  *
   8  */
   9
  10 #if defined(USE_5005THREADS) || defined(USE_ITHREADS)
  11
  12 #if defined(VMS)
  13 #include <builtins.h>
  14 #endif
  15
  16 #ifdef WIN32
  17 #  include <win32thread.h>
  18 #else
  19 #ifdef NETWARE
  20 #  include <nw5thread.h>
  21 #else
  22 #  ifdef OLD_PTHREADS_API /* Here be dragons. */
  23 #    define DETACH(t) \
  24     STMT_START {                                                \
  25         if (pthread_detach(&(t)->self)) {                       \
  26             MUTEX_UNLOCK(&(t)->mutex);                          \
  27             Perl_croak_nocontext("panic: DETACH");              \
  28         }                                                       \
  29     } STMT_END
  30
  31 #    define PERL_GET_CONTEXT    Perl_get_context()
  32 #    define PERL_SET_CONTEXT(t) Perl_set_context((void*)t)
  33
  34 #    define PTHREAD_GETSPECIFIC_INT
  35 #    ifdef DJGPP
  36 #      define pthread_addr_t any_t
  37 #      define NEED_PTHREAD_INIT
  38 #      define PTHREAD_CREATE_JOINABLE (1)
  39 #    endif
  40 #    ifdef __OPEN_VM
  41 #      define pthread_addr_t void *
  42 #    endif
  43 #    ifdef VMS
  44 #      define pthread_attr_init(a) pthread_attr_create(a)
  45 #      define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_setdetach_np(a,s)
  46 #      define PTHREAD_CREATE(t,a,s,d) pthread_create(t,a,s,d)
  47 #      define pthread_key_create(k,d) pthread_keycreate(k,(pthread_destructor_t)(d))
  48 #      define pthread_mutexattr_init(a) pthread_mutexattr_create(a)
  49 #      define pthread_mutexattr_settype(a,t) pthread_mutexattr_setkind_np(a,t)
  50 #    endif
  51 #    if defined(__hpux) && defined(__ux_version) && __ux_version <= 1020
  52 #      define pthread_attr_init(a) pthread_attr_create(a)
  53        /* XXX pthread_setdetach_np() missing in DCE threads on HP-UX 10.20 */
  54 #      define PTHREAD_ATTR_SETDETACHSTATE(a,s)  (0)
  55 #      define PTHREAD_CREATE(t,a,s,d) pthread_create(t,a,s,d)
  56 #      define pthread_key_create(k,d) pthread_keycreate(k,(pthread_destructor_t)(d))
  57 #      define pthread_mutexattr_init(a) pthread_mutexattr_create(a)
  58 #      define pthread_mutexattr_settype(a,t) pthread_mutexattr_setkind_np(a,t)
  59 #    endif
  60 #    if defined(DJGPP) || defined(__OPEN_VM)
  61 #      define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_attr_setdetachstate(a,&(s))
  62 #      define YIELD pthread_yield(NULL)
  63 #    endif
  64 #  endif
  65 #  if !defined(__hpux) || !defined(__ux_version) || __ux_version > 1020
  66 #    define pthread_mutexattr_default NULL
  67 #    define pthread_condattr_default  NULL
  68 #  endif
  69 #endif  /* NETWARE */
  70 #endif
  71
  72 #ifndef PTHREAD_CREATE
  73 /* You are not supposed to pass NULL as the 2nd arg of PTHREAD_CREATE(). */
  74 #  define PTHREAD_CREATE(t,a,s,d) pthread_create(t,&(a),s,d)
  75 #endif
  76
  77 #ifndef PTHREAD_ATTR_SETDETACHSTATE
  78 #  define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_attr_setdetachstate(a,s)
  79 #endif
  80
  81 #ifndef PTHREAD_CREATE_JOINABLE
  82 #  ifdef OLD_PTHREAD_CREATE_JOINABLE
  83 #    define PTHREAD_CREATE_JOINABLE OLD_PTHREAD_CREATE_JOINABLE
  84 #  else
  85 #    define PTHREAD_CREATE_JOINABLE 0 /* Panic?  No, guess. */
  86 #  endif
  87 #endif
  88
  89 #ifdef DGUX
  90 #  define THREAD_CREATE_NEEDS_STACK (32*1024)
  91 #endif
  92
  93 #ifdef I_MACH_CTHREADS
  94
  95 /* cthreads interface */
  96
  97 /* #include <mach/cthreads.h> is in perl.h #ifdef I_MACH_CTHREADS */
  98
  99 #define MUTEX_INIT(m) \
 100     STMT_START {                                                \
 101         *m = mutex_alloc();                                     \
 102         if (*m) {                                               \
 103             mutex_init(*m);                                     \
 104         } else {                                                \
 105             Perl_croak_nocontext("panic: MUTEX_INIT");          \
 106         }                                                       \
 107     } STMT_END
 108
 109 #define MUTEX_LOCK(m)                   mutex_lock(*m)
 110 #define MUTEX_UNLOCK(m)                 mutex_unlock(*m)
 111 #define MUTEX_DESTROY(m) \
 112     STMT_START {                                                \
 113         mutex_free(*m);                                         \
 114         *m = 0;                                                 \
 115     } STMT_END
 116
 117 #define COND_INIT(c) \
 118     STMT_START {                                                \
 119         *c = condition_alloc();                                 \
 120         if (*c) {                                               \
 121             condition_init(*c);                                 \
 122         }                                                       \
 123         else {                                                  \
 124             Perl_croak_nocontext("panic: COND_INIT");           \
 125         }                                                       \
 126     } STMT_END
 127
 128 #define COND_SIGNAL(c)          condition_signal(*c)
 129 #define COND_BROADCAST(c)       condition_broadcast(*c)
 130 #define COND_WAIT(c, m)         condition_wait(*c, *m)
 131 #define COND_DESTROY(c) \
 132     STMT_START {                                                \
 133         condition_free(*c);                                     \
 134         *c = 0;                                                 \
 135     } STMT_END
 136
 137 #define THREAD_CREATE(thr, f)   (thr->self = cthread_fork(f, thr), 0)
 138 #define THREAD_POST_CREATE(thr)
 139
 140 #define THREAD_RET_TYPE         any_t
 141 #define THREAD_RET_CAST(x)      ((any_t) x)
 142
 143 #define DETACH(t)               cthread_detach(t->self)
 144 #define JOIN(t, avp)            (*(avp) = (AV *)cthread_join(t->self))
 145
 146 #define PERL_SET_CONTEXT(t)     cthread_set_data(cthread_self(), t)
 147 #define PERL_GET_CONTEXT        cthread_data(cthread_self())
 148
 149 #define INIT_THREADS            cthread_init()
 150 #define YIELD                   cthread_yield()
 151 #define ALLOC_THREAD_KEY        NOOP
 152 #define FREE_THREAD_KEY         NOOP
 153 #define SET_THREAD_SELF(thr)    (thr->self = cthread_self())
 154
 155 #endif /* I_MACH_CTHREADS */
 156
 157 #ifndef YIELD
 158 #  ifdef SCHED_YIELD
 159 #    define YIELD SCHED_YIELD
 160 #  else
 161 #    ifdef HAS_SCHED_YIELD
 162 #      define YIELD sched_yield()
 163 #    else
 164 #      ifdef HAS_PTHREAD_YIELD
 165     /* pthread_yield(NULL) platforms are expected
 166      * to have #defined YIELD for themselves. */
 167 #        define YIELD pthread_yield()
 168 #      endif
 169 #    endif
 170 #  endif
 171 #endif
 172
 173 #ifdef __hpux
 174 #  define MUTEX_INIT_NEEDS_MUTEX_ZEROED
 175 #endif
 176
 177 #ifndef MUTEX_INIT
 178
 179 #  ifdef MUTEX_INIT_NEEDS_MUTEX_ZEROED
 180     /* Temporary workaround, true bug is deeper. --jhi 1999-02-25 */
 181 #    define MUTEX_INIT(m) \
 182     STMT_START {                                                \
 183         Zero((m), 1, perl_mutex);                               \
 184         if (pthread_mutex_init((m), pthread_mutexattr_default)) \
 185             Perl_croak_nocontext("panic: MUTEX_INIT");          \
 186     } STMT_END
 187 #  else
 188 #    define MUTEX_INIT(m) \
 189     STMT_START {                                                \
 190         if (pthread_mutex_init((m), pthread_mutexattr_default)) \
 191             Perl_croak_nocontext("panic: MUTEX_INIT");          \
 192     } STMT_END
 193 #  endif
 194
 195 #  define MUTEX_LOCK(m) \
 196     STMT_START {                                                \
 197         if (pthread_mutex_lock((m)))                            \
 198             Perl_croak_nocontext("panic: MUTEX_LOCK");          \
 199     } STMT_END
 200
 201 #  define MUTEX_UNLOCK(m) \
 202     STMT_START {                                                \
 203         if (pthread_mutex_unlock((m)))                          \
 204             Perl_croak_nocontext("panic: MUTEX_UNLOCK");        \
 205     } STMT_END
 206
 207 #  define MUTEX_DESTROY(m) \
 208     STMT_START {                                                \
 209         if (pthread_mutex_destroy((m)))                         \
 210             Perl_croak_nocontext("panic: MUTEX_DESTROY");       \
 211     } STMT_END
 212 #endif /* MUTEX_INIT */
 213
 214 #ifndef COND_INIT
 215 #  define COND_INIT(c) \
 216     STMT_START {                                                \
 217         if (pthread_cond_init((c), pthread_condattr_default))   \
 218             Perl_croak_nocontext("panic: COND_INIT");           \
 219     } STMT_END
 220
 221 #  define COND_SIGNAL(c) \
 222     STMT_START {                                                \
 223         if (pthread_cond_signal((c)))                           \
 224             Perl_croak_nocontext("panic: COND_SIGNAL");         \
 225     } STMT_END
 226
 227 #  define COND_BROADCAST(c) \
 228     STMT_START {                                                \
 229         if (pthread_cond_broadcast((c)))                        \
 230             Perl_croak_nocontext("panic: COND_BROADCAST");      \
 231     } STMT_END
 232
 233 #  define COND_WAIT(c, m) \
 234     STMT_START {                                                \
 235         if (pthread_cond_wait((c), (m)))                        \
 236             Perl_croak_nocontext("panic: COND_WAIT");           \
 237     } STMT_END
 238
 239 #  define COND_DESTROY(c) \
 240     STMT_START {                                                \
 241         if (pthread_cond_destroy((c)))                          \
 242             Perl_croak_nocontext("panic: COND_DESTROY");        \
 243     } STMT_END
 244 #endif /* COND_INIT */
 245
 246 /* DETACH(t) must only be called while holding t->mutex */
 247 #ifndef DETACH
 248 #  define DETACH(t) \
 249     STMT_START {                                                \
 250         if (pthread_detach((t)->self)) {                        \
 251             MUTEX_UNLOCK(&(t)->mutex);                          \
 252             Perl_croak_nocontext("panic: DETACH");              \
 253         }                                                       \
 254     } STMT_END
 255 #endif /* DETACH */
 256
 257 #ifndef JOIN
 258 #  define JOIN(t, avp) \
 259     STMT_START {                                                \
 260         if (pthread_join((t)->self, (void**)(avp)))             \
 261             Perl_croak_nocontext("panic: pthread_join");        \
 262     } STMT_END
 263 #endif /* JOIN */
 264
 265 /* Use an unchecked fetch of thread-specific data instead of a checked one.
 266  * It would fail if the key were bogus, but if the key were bogus then
 267  * Really Bad Things would be happening anyway. --dan */
 268 #if (defined(__ALPHA) && (__VMS_VER >= 70000000)) || \
 269     (defined(__alpha) && defined(__osf__)) /* Available only on >= 4.0 */
 270 #  define HAS_PTHREAD_UNCHECKED_GETSPECIFIC_NP /* Configure test needed */
 271 #endif
 272
 273 #ifdef HAS_PTHREAD_UNCHECKED_GETSPECIFIC_NP
 274 #  define PTHREAD_GETSPECIFIC(key) pthread_unchecked_getspecific_np(key)
 275 #else
 276 #  define PTHREAD_GETSPECIFIC(key) pthread_getspecific(key)
 277 #endif
 278
 279 #ifndef PERL_GET_CONTEXT
 280 #  define PERL_GET_CONTEXT      PTHREAD_GETSPECIFIC(PL_thr_key)
 281 #endif
 282
 283 #ifndef PERL_SET_CONTEXT
 284 #  define PERL_SET_CONTEXT(t) \
 285     STMT_START {                                                \
 286         if (pthread_setspecific(PL_thr_key, (void *)(t)))       \
 287             Perl_croak_nocontext("panic: pthread_setspecific"); \
 288     } STMT_END
 289 #endif /* PERL_SET_CONTEXT */
 290
 291 #ifndef INIT_THREADS
 292 #  ifdef NEED_PTHREAD_INIT
 293 #    define INIT_THREADS pthread_init()
 294 #  endif
 295 #endif
 296
 297 #ifndef ALLOC_THREAD_KEY
 298 #  define ALLOC_THREAD_KEY \
 299     STMT_START {                                                \
 300         if (pthread_key_create(&PL_thr_key, 0)) {               \
 301             PerlIO_printf(PerlIO_stderr(), "panic: pthread_key_create");        \
 302             exit(1);                                            \
 303         }                                                       \
 304     } STMT_END
 305 #endif
 306
 307 #ifndef FREE_THREAD_KEY
 308 #  define FREE_THREAD_KEY \
 309     STMT_START {                                                \
 310         pthread_key_delete(PL_thr_key);                         \
 311     } STMT_END
 312 #endif
 313
 314 #ifndef PTHREAD_ATFORK
 315 #  ifdef HAS_PTHREAD_ATFORK
 316 #    define PTHREAD_ATFORK(prepare,parent,child)                \
 317         pthread_atfork(prepare,parent,child)
 318 #  else
 319 #    define PTHREAD_ATFORK(prepare,parent,child)                \
 320         NOOP
 321 #  endif
 322 #endif
 323
 324 #ifndef THREAD_RET_TYPE
 325 #  define THREAD_RET_TYPE       void *
 326 #  define THREAD_RET_CAST(p)    ((void *)(p))
 327 #endif /* THREAD_RET */
 328
 329 #if defined(USE_5005THREADS)
 330
 331 /* Accessor for per-thread SVs */
 332 #  define THREADSV(i) (thr->threadsvp[i])
 333
 334 /*
 335  * LOCK_SV_MUTEX and UNLOCK_SV_MUTEX are performance-critical. Here, we
 336  * try only locking them if there may be more than one thread in existence.
 337  * Systems with very fast mutexes (and/or slow conditionals) may wish to
 338  * remove the "if (threadnum) ..." test.
 339  * XXX do NOT use C<if (PL_threadnum) ...> -- it sets up race conditions!
 340  */
 341 #  define LOCK_SV_MUTEX         MUTEX_LOCK(&PL_sv_mutex)
 342 #  define UNLOCK_SV_MUTEX       MUTEX_UNLOCK(&PL_sv_mutex)
 343 #  define LOCK_STRTAB_MUTEX     MUTEX_LOCK(&PL_strtab_mutex)
 344 #  define UNLOCK_STRTAB_MUTEX   MUTEX_UNLOCK(&PL_strtab_mutex)
 345 #  define LOCK_CRED_MUTEX       MUTEX_LOCK(&PL_cred_mutex)
 346 #  define UNLOCK_CRED_MUTEX     MUTEX_UNLOCK(&PL_cred_mutex)
 347 #  define LOCK_FDPID_MUTEX      MUTEX_LOCK(&PL_fdpid_mutex)
 348 #  define UNLOCK_FDPID_MUTEX    MUTEX_UNLOCK(&PL_fdpid_mutex)
 349 #  define LOCK_SV_LOCK_MUTEX    MUTEX_LOCK(&PL_sv_lock_mutex)
 350 #  define UNLOCK_SV_LOCK_MUTEX  MUTEX_UNLOCK(&PL_sv_lock_mutex)
 351
 352 /* Values and macros for thr->flags */
 353 #define THRf_STATE_MASK 7
 354 #define THRf_R_JOINABLE 0
 355 #define THRf_R_JOINED   1
 356 #define THRf_R_DETACHED 2
 357 #define THRf_ZOMBIE     3
 358 #define THRf_DEAD       4
 359
 360 #define THRf_DID_DIE    8
 361
 362 /* ThrSTATE(t) and ThrSETSTATE(t) must only be called while holding t->mutex */
 363 #define ThrSTATE(t) ((t)->flags & THRf_STATE_MASK)
 364 #define ThrSETSTATE(t, s) STMT_START {          \
 365         (t)->flags &= ~THRf_STATE_MASK;         \
 366         (t)->flags |= (s);                      \
 367         DEBUG_S(PerlIO_printf(Perl_debug_log,   \
 368                               "thread %p set to state %d\n", (t), (s))); \
 369     } STMT_END
 370
 371 typedef struct condpair {
 372     perl_mutex  mutex;          /* Protects all other fields */
 373     perl_cond   owner_cond;     /* For when owner changes at all */
 374     perl_cond   cond;           /* For cond_signal and cond_broadcast */
 375     Thread      owner;          /* Currently owning thread */
 376 } condpair_t;
 377
 378 #define MgMUTEXP(mg) (&((condpair_t *)(mg->mg_ptr))->mutex)
 379 #define MgOWNERCONDP(mg) (&((condpair_t *)(mg->mg_ptr))->owner_cond)
 380 #define MgCONDP(mg) (&((condpair_t *)(mg->mg_ptr))->cond)
 381 #define MgOWNER(mg) ((condpair_t *)(mg->mg_ptr))->owner
 382
 383 #endif /* USE_5005THREADS */
 384 #endif /* USE_5005THREADS || USE_ITHREADS */
 385
 386 #ifndef MUTEX_LOCK
 387 #  define MUTEX_LOCK(m)
 388 #endif
 389
 390 #ifndef MUTEX_UNLOCK
 391 #  define MUTEX_UNLOCK(m)
 392 #endif
 393
 394 #ifndef MUTEX_INIT
 395 #  define MUTEX_INIT(m)
 396 #endif
 397
 398 #ifndef MUTEX_DESTROY
 399 #  define MUTEX_DESTROY(m)
 400 #endif
 401
 402 #ifndef COND_INIT
 403 #  define COND_INIT(c)
 404 #endif
 405
 406 #ifndef COND_SIGNAL
 407 #  define COND_SIGNAL(c)
 408 #endif
 409
 410 #ifndef COND_BROADCAST
 411 #  define COND_BROADCAST(c)
 412 #endif
 413
 414 #ifndef COND_WAIT
 415 #  define COND_WAIT(c, m)
 416 #endif
 417
 418 #ifndef COND_DESTROY
 419 #  define COND_DESTROY(c)
 420 #endif
 421
 422 #ifndef LOCK_SV_MUTEX
 423 #  define LOCK_SV_MUTEX
 424 #endif
 425
 426 #ifndef UNLOCK_SV_MUTEX
 427 #  define UNLOCK_SV_MUTEX
 428 #endif
 429
 430 #ifndef LOCK_STRTAB_MUTEX
 431 #  define LOCK_STRTAB_MUTEX
 432 #endif
 433
 434 #ifndef UNLOCK_STRTAB_MUTEX
 435 #  define UNLOCK_STRTAB_MUTEX
 436 #endif
 437
 438 #ifndef LOCK_CRED_MUTEX
 439 #  define LOCK_CRED_MUTEX
 440 #endif
 441
 442 #ifndef UNLOCK_CRED_MUTEX
 443 #  define UNLOCK_CRED_MUTEX
 444 #endif
 445
 446 #ifndef LOCK_FDPID_MUTEX
 447 #  define LOCK_FDPID_MUTEX
 448 #endif
 449
 450 #ifndef UNLOCK_FDPID_MUTEX
 451 #  define UNLOCK_FDPID_MUTEX
 452 #endif
 453
 454 #ifndef LOCK_SV_LOCK_MUTEX
 455 #  define LOCK_SV_LOCK_MUTEX
 456 #endif
 457
 458 #ifndef UNLOCK_SV_LOCK_MUTEX
 459 #  define UNLOCK_SV_LOCK_MUTEX
 460 #endif
 461
 462 /* THR, SET_THR, and dTHR are there for compatibility with old versions */
 463 #ifndef THR
 464 #  define THR           PERL_GET_THX
 465 #endif
 466
 467 #ifndef SET_THR
 468 #  define SET_THR(t)    PERL_SET_THX(t)
 469 #endif
 470
 471 #ifndef dTHR
 472 #  define dTHR dNOOP
 473 #endif
 474
 475 #ifndef INIT_THREADS
 476 #  define INIT_THREADS NOOP
 477 #endif