thread.h

   1 #ifdef USE_THREADS
   2
   3 #ifdef WIN32
   4 #  include <win32thread.h>
   5 #else
   6 #  ifdef OLD_PTHREADS_API /* Here be dragons. */
   7 #    define DETACH(t)                           \
   8     STMT_START {                                \
   9         if (pthread_detach(&(t)->self)) {       \
  10             MUTEX_UNLOCK(&(t)->mutex);          \
  11             croak("panic: DETACH");             \
  12         }                                       \
  13     } STMT_END
  14 #    define THR getTHR()
  15 struct perl_thread *getTHR _((void));
  16 #    define PTHREAD_GETSPECIFIC_INT
  17 #    ifdef DJGPP
  18 #      define pthread_addr_t any_t
  19 #      define NEED_PTHREAD_INIT
  20 #      define PTHREAD_CREATE_JOINABLE (1)
  21 #    endif
  22 #    ifdef __OPEN_VM
  23 #      define pthread_addr_t void *
  24 #    endif
  25 #    ifdef VMS
  26 #      define pthread_attr_init(a) pthread_attr_create(a)
  27 #      define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_setdetach_np(a,s)
  28 #      define PTHREAD_CREATE(t,a,s,d) pthread_create(t,a,s,d)
  29 #      define pthread_key_create(k,d) pthread_keycreate(k,(pthread_destructor_t)(d))
  30 #      define pthread_mutexattr_init(a) pthread_mutexattr_create(a)
  31 #      define pthread_mutexattr_settype(a,t) pthread_mutexattr_setkind_np(a,t)
  32 #    endif
  33 #    if defined(DJGPP) || defined(__OPEN_VM)
  34 #      define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_attr_setdetachstate(a,&(s))
  35 #      define YIELD pthread_yield(NULL)
  36 #    endif
  37 #  endif
  38 #  ifndef VMS
  39 #    define pthread_mutexattr_default NULL
  40 #    define pthread_condattr_default  NULL
  41 #  endif
  42 #endif
  43
  44 #ifndef PTHREAD_CREATE
  45 /* You are not supposed to pass NULL as the 2nd arg of PTHREAD_CREATE(). */
  46 #  define PTHREAD_CREATE(t,a,s,d) pthread_create(t,&(a),s,d)
  47 #endif
  48
  49 #ifndef PTHREAD_ATTR_SETDETACHSTATE
  50 #  define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_attr_setdetachstate(a,s)
  51 #endif
  52
  53 #ifndef PTHREAD_CREATE_JOINABLE
  54 #  ifdef OLD_PTHREAD_CREATE_JOINABLE
  55 #    define PTHREAD_CREATE_JOINABLE OLD_PTHREAD_CREATE_JOINABLE
  56 #  else
  57 #    define PTHREAD_CREATE_JOINABLE 0 /* Panic?  No, guess. */
  58 #  endif
  59 #endif
  60
  61 #ifdef I_MACH_CTHREADS
  62
  63 /* cthreads interface */
  64
  65 /* #include <mach/cthreads.h> is in perl.h #ifdef I_MACH_CTHREADS */
  66
  67 #define MUTEX_INIT(m)                                   \
  68         STMT_START {                                    \
  69                 *m = mutex_alloc();                     \
  70                 if (*m) {                               \
  71                         mutex_init(*m);                 \
  72                 } else {                                \
  73                         croak("panic: MUTEX_INIT");     \
  74                 }                                       \
  75         } STMT_END
  76
  77 #define MUTEX_LOCK(m)           mutex_lock(*m)
  78 #define MUTEX_UNLOCK(m)         mutex_unlock(*m)
  79 #define MUTEX_DESTROY(m)                                \
  80         STMT_START {                                    \
  81                 mutex_free(*m);                         \
  82                 *m = 0;                                 \
  83         } STMT_END
  84
  85 #define COND_INIT(c)                                    \
  86         STMT_START {                                    \
  87                 *c = condition_alloc();                 \
  88                 if (*c) {                               \
  89                         condition_init(*c);             \
  90                 } else {                                \
  91                         croak("panic: COND_INIT");      \
  92                 }                                       \
  93         } STMT_END
  94
  95 #define COND_SIGNAL(c)          condition_signal(*c)
  96 #define COND_BROADCAST(c)       condition_broadcast(*c)
  97 #define COND_WAIT(c, m)         condition_wait(*c, *m)
  98 #define COND_DESTROY(c)                         \
  99         STMT_START {                            \
 100                 condition_free(*c);             \
 101                 *c = 0;                         \
 102         } STMT_END
 103
 104 #define THREAD_CREATE(thr, f)   (thr->self = cthread_fork(f, thr), 0)
 105 #define THREAD_POST_CREATE(thr)
 106
 107 #define THREAD_RET_TYPE         any_t
 108 #define THREAD_RET_CAST(x)      ((any_t) x)
 109
 110 #define DETACH(t)               cthread_detach(t->self)
 111 #define JOIN(t, avp)            (*(avp) = (AV *)cthread_join(t->self))
 112
 113 #define SET_THR(thr)            cthread_set_data(cthread_self(), thr)
 114 #define THR                     cthread_data(cthread_self())
 115
 116 #define INIT_THREADS            cthread_init()
 117 #define YIELD                   cthread_yield()
 118 #define ALLOC_THREAD_KEY
 119 #define SET_THREAD_SELF(thr)    (thr->self = cthread_self())
 120
 121 #endif /* I_MACH_CTHREADS */
 122
 123 #ifndef YIELD
 124 #  ifdef SCHED_YIELD
 125 #    define YIELD SCHED_YIELD
 126 #  else
 127 #    ifdef HAS_SCHED_YIELD
 128 #      define YIELD sched_yield()
 129 #    else
 130 #      ifdef HAS_PTHREAD_YIELD
 131     /* pthread_yield(NULL) platforms are expected
 132      * to have #defined YIELD for themselves. */
 133 #        define YIELD pthread_yield()
 134 #      endif
 135 #    endif
 136 #  endif
 137 #endif
 138
 139 #ifdef __hpux
 140 #  define MUTEX_INIT_NEEDS_MUTEX_ZEROED
 141 #endif
 142
 143 #ifndef MUTEX_INIT
 144 #ifdef MUTEX_INIT_NEEDS_MUTEX_ZEROED
 145     /* Temporary workaround, true bug is deeper. --jhi 1999-02-25 */
 146 #define MUTEX_INIT(m)                                           \
 147     STMT_START {                                                \
 148         Zero((m), 1, perl_mutex);                               \
 149         if (pthread_mutex_init((m), pthread_mutexattr_default)) \
 150             croak("panic: MUTEX_INIT");                         \
 151     } STMT_END
 152 #else
 153 #define MUTEX_INIT(m)                                           \
 154     STMT_START {                                                \
 155         if (pthread_mutex_init((m), pthread_mutexattr_default)) \
 156             croak("panic: MUTEX_INIT");                         \
 157     } STMT_END
 158 #endif
 159 #define MUTEX_LOCK(m)                           \
 160     STMT_START {                                \
 161         if (pthread_mutex_lock((m)))            \
 162             croak("panic: MUTEX_LOCK");         \
 163     } STMT_END
 164 #define MUTEX_UNLOCK(m)                         \
 165     STMT_START {                                \
 166         if (pthread_mutex_unlock((m)))          \
 167             croak("panic: MUTEX_UNLOCK");       \
 168     } STMT_END
 169 #define MUTEX_DESTROY(m)                        \
 170     STMT_START {                                \
 171         if (pthread_mutex_destroy((m)))         \
 172             croak("panic: MUTEX_DESTROY");      \
 173     } STMT_END
 174 #endif /* MUTEX_INIT */
 175
 176 #ifndef COND_INIT
 177 #define COND_INIT(c)                                            \
 178     STMT_START {                                                \
 179         if (pthread_cond_init((c), pthread_condattr_default))   \
 180             croak("panic: COND_INIT");                          \
 181     } STMT_END
 182 #define COND_SIGNAL(c)                          \
 183     STMT_START {                                \
 184         if (pthread_cond_signal((c)))           \
 185             croak("panic: COND_SIGNAL");        \
 186     } STMT_END
 187 #define COND_BROADCAST(c)                       \
 188     STMT_START {                                \
 189         if (pthread_cond_broadcast((c)))        \
 190             croak("panic: COND_BROADCAST");     \
 191     } STMT_END
 192 #define COND_WAIT(c, m)                         \
 193     STMT_START {                                \
 194         if (pthread_cond_wait((c), (m)))        \
 195             croak("panic: COND_WAIT");          \
 196     } STMT_END
 197 #define COND_DESTROY(c)                         \
 198     STMT_START {                                \
 199         if (pthread_cond_destroy((c)))          \
 200             croak("panic: COND_DESTROY");       \
 201     } STMT_END
 202 #endif /* COND_INIT */
 203
 204 /* DETACH(t) must only be called while holding t->mutex */
 205 #ifndef DETACH
 206 #define DETACH(t)                               \
 207     STMT_START {                                \
 208         if (pthread_detach((t)->self)) {        \
 209             MUTEX_UNLOCK(&(t)->mutex);          \
 210             croak("panic: DETACH");             \
 211         }                                       \
 212     } STMT_END
 213 #endif /* DETACH */
 214
 215 #ifndef JOIN
 216 #define JOIN(t, avp)                                    \
 217     STMT_START {                                        \
 218         if (pthread_join((t)->self, (void**)(avp)))     \
 219             croak("panic: pthread_join");               \
 220     } STMT_END
 221 #endif /* JOIN */
 222
 223 #ifndef SET_THR
 224 #define SET_THR(t)                                      \
 225     STMT_START {                                        \
 226         if (pthread_setspecific(PL_thr_key, (void *) (t)))      \
 227             croak("panic: pthread_setspecific");        \
 228     } STMT_END
 229 #endif /* SET_THR */
 230
 231 #ifndef THR
 232 #define THR ((struct perl_thread *) pthread_getspecific(PL_thr_key))
 233 #endif
 234
 235 /*
 236  * dTHR is performance-critical. Here, we only do the pthread_get_specific
 237  * if there may be more than one thread in existence, otherwise we get thr
 238  * from thrsv which is cached in the per-interpreter structure.
 239  * Systems with very fast pthread_get_specific (which should be all systems
 240  * but unfortunately isn't) may wish to simplify to "...*thr = THR".
 241  *
 242  * The use of PL_threadnum should be safe here.
 243  */
 244 #ifndef dTHR
 245 #  define dTHR \
 246     struct perl_thread *thr = PL_threadnum? THR : (struct perl_thread*)SvPVX(PL_thrsv)
 247 #endif /* dTHR */
 248
 249 #ifndef INIT_THREADS
 250 #  ifdef NEED_PTHREAD_INIT
 251 #    define INIT_THREADS pthread_init()
 252 #  else
 253 #    define INIT_THREADS NOOP
 254 #  endif
 255 #endif
 256
 257 /* Accessor for per-thread SVs */
 258 #define THREADSV(i) (thr->threadsvp[i])
 259
 260 /*
 261  * LOCK_SV_MUTEX and UNLOCK_SV_MUTEX are performance-critical. Here, we
 262  * try only locking them if there may be more than one thread in existence.
 263  * Systems with very fast mutexes (and/or slow conditionals) may wish to
 264  * remove the "if (threadnum) ..." test.
 265  * XXX do NOT use C<if (PL_threadnum) ...> -- it sets up race conditions!
 266  */
 267 #define LOCK_SV_MUTEX                           \
 268     STMT_START {                                \
 269         MUTEX_LOCK(&PL_sv_mutex);               \
 270     } STMT_END
 271
 272 #define UNLOCK_SV_MUTEX                         \
 273     STMT_START {                                \
 274         MUTEX_UNLOCK(&PL_sv_mutex);             \
 275     } STMT_END
 276
 277 /* Likewise for strtab_mutex */
 278 #define LOCK_STRTAB_MUTEX                       \
 279     STMT_START {                                \
 280         MUTEX_LOCK(&PL_strtab_mutex);           \
 281     } STMT_END
 282
 283 #define UNLOCK_STRTAB_MUTEX                     \
 284     STMT_START {                                \
 285         MUTEX_UNLOCK(&PL_strtab_mutex);         \
 286     } STMT_END
 287
 288 #ifndef THREAD_RET_TYPE
 289 #  define THREAD_RET_TYPE       void *
 290 #  define THREAD_RET_CAST(p)    ((void *)(p))
 291 #endif /* THREAD_RET */
 292
 293
 294 /* Values and macros for thr->flags */
 295 #define THRf_STATE_MASK 7
 296 #define THRf_R_JOINABLE 0
 297 #define THRf_R_JOINED   1
 298 #define THRf_R_DETACHED 2
 299 #define THRf_ZOMBIE     3
 300 #define THRf_DEAD       4
 301
 302 #define THRf_DID_DIE    8
 303
 304 /* ThrSTATE(t) and ThrSETSTATE(t) must only be called while holding t->mutex */
 305 #define ThrSTATE(t) ((t)->flags & THRf_STATE_MASK)
 306 #define ThrSETSTATE(t, s) STMT_START {          \
 307         (t)->flags &= ~THRf_STATE_MASK;         \
 308         (t)->flags |= (s);                      \
 309         DEBUG_S(PerlIO_printf(PerlIO_stderr(),  \
 310                               "thread %p set to state %d\n", (t), (s))); \
 311     } STMT_END
 312
 313 typedef struct condpair {
 314     perl_mutex  mutex;          /* Protects all other fields */
 315     perl_cond   owner_cond;     /* For when owner changes at all */
 316     perl_cond   cond;           /* For cond_signal and cond_broadcast */
 317     Thread      owner;          /* Currently owning thread */
 318 } condpair_t;
 319
 320 #define MgMUTEXP(mg) (&((condpair_t *)(mg->mg_ptr))->mutex)
 321 #define MgOWNERCONDP(mg) (&((condpair_t *)(mg->mg_ptr))->owner_cond)
 322 #define MgCONDP(mg) (&((condpair_t *)(mg->mg_ptr))->cond)
 323 #define MgOWNER(mg) ((condpair_t *)(mg->mg_ptr))->owner
 324
 325 #else
 326 /* USE_THREADS is not defined */
 327 #define MUTEX_LOCK(m)
 328 #define MUTEX_UNLOCK(m)
 329 #define MUTEX_INIT(m)
 330 #define MUTEX_DESTROY(m)
 331 #define COND_INIT(c)
 332 #define COND_SIGNAL(c)
 333 #define COND_BROADCAST(c)
 334 #define COND_WAIT(c, m)
 335 #define COND_DESTROY(c)
 336 #define LOCK_SV_MUTEX
 337 #define UNLOCK_SV_MUTEX
 338 #define LOCK_STRTAB_MUTEX
 339 #define UNLOCK_STRTAB_MUTEX
 340
 341 #define THR
 342 /* Rats: if dTHR is just blank then the subsequent ";" throws an error */
 343 #ifdef WIN32
 344 #define dTHR extern int Perl___notused
 345 #else
 346 #define dTHR extern int errno
 347 #endif
 348 #endif /* USE_THREADS */