thread.h

   1 #ifdef USE_THREADS
   2
   3 #ifdef WIN32
   4 #  include <win32thread.h>
   5 #else
   6 /* XXX What we really need is Configure probing for all of these
   7  * pthread thingies, old, medium, and new, not the blanket statement of
   8  * OLD_PTHREADS_API. --jhi */
   9 #  if defined(OLD_PTHREADS_API) && !defined(DJGPP) && !defined(__OPEN_VM) && !defined(OEMVS)
  10      /* POSIXish threads */
  11 #    define pthread_mutexattr_init(a) pthread_mutexattr_create(a)
  12 #    define pthread_mutexattr_settype(a,t) pthread_mutexattr_setkind_np(a,t)
  13 #    define pthread_key_create(k,d) pthread_keycreate(k,(pthread_destructor_t)(d))
  14 #    define DETACH(t)                           \
  15     STMT_START {                                \
  16         if (pthread_detach(&(t)->self)) {       \
  17             MUTEX_UNLOCK(&(t)->mutex);          \
  18             croak("panic: DETACH");             \
  19         }                                       \
  20     } STMT_END
  21 #  else
  22 #    define pthread_mutexattr_default NULL
  23 #    define pthread_condattr_default NULL
  24 #  endif /* OLD_PTHREADS_API */
  25 #endif
  26
  27 #ifndef YIELD
  28 #  ifdef SCHED_YIELD
  29 #    define YIELD SCHED_YIELD
  30 #  else
  31 #    ifdef HAS_SCHED_YIELD
  32 #      define YIELD sched_yield()
  33 #    else
  34 #      ifdef HAS_PTHREAD_YIELD
  35     /* pthread_yield(NULL) platforms are expected
  36      * to have #defined YIELD for themselves. */
  37 #        define YIELD pthread_yield()
  38 #      endif
  39 #    endif
  40 #  endif
  41 #endif
  42
  43 #ifdef PTHREADS_CREATED_JOINABLE
  44 #  define ATTR_JOINABLE PTHREAD_CREATE_JOINABLE
  45 #else
  46 #  ifdef PTHREAD_CREATE_UNDETACHED
  47 #    define ATTR_JOINABLE PTHREAD_CREATE_UNDETACHED
  48 #  else
  49 #    ifdef __UNDETACHED
  50 #      define ATTR_JOINABLE __UNDETACHED
  51 #    endif
  52 #  endif
  53 #endif
  54
  55 #ifndef MUTEX_INIT
  56 #define MUTEX_INIT(m)                                           \
  57     STMT_START {                                                \
  58         if (pthread_mutex_init((m), pthread_mutexattr_default)) \
  59             croak("panic: MUTEX_INIT");                         \
  60     } STMT_END
  61 #define MUTEX_LOCK(m)                           \
  62     STMT_START {                                \
  63         if (pthread_mutex_lock((m)))            \
  64             croak("panic: MUTEX_LOCK");         \
  65     } STMT_END
  66 #define MUTEX_UNLOCK(m)                         \
  67     STMT_START {                                \
  68         if (pthread_mutex_unlock((m)))          \
  69             croak("panic: MUTEX_UNLOCK");       \
  70     } STMT_END
  71 #define MUTEX_DESTROY(m)                        \
  72     STMT_START {                                \
  73         if (pthread_mutex_destroy((m)))         \
  74             croak("panic: MUTEX_DESTROY");      \
  75     } STMT_END
  76 #endif /* MUTEX_INIT */
  77
  78 #ifndef COND_INIT
  79 #define COND_INIT(c)                                            \
  80     STMT_START {                                                \
  81         if (pthread_cond_init((c), pthread_condattr_default))   \
  82             croak("panic: COND_INIT");                          \
  83     } STMT_END
  84 #define COND_SIGNAL(c)                          \
  85     STMT_START {                                \
  86         if (pthread_cond_signal((c)))           \
  87             croak("panic: COND_SIGNAL");        \
  88     } STMT_END
  89 #define COND_BROADCAST(c)                       \
  90     STMT_START {                                \
  91         if (pthread_cond_broadcast((c)))        \
  92             croak("panic: COND_BROADCAST");     \
  93     } STMT_END
  94 #define COND_WAIT(c, m)                         \
  95     STMT_START {                                \
  96         if (pthread_cond_wait((c), (m)))        \
  97             croak("panic: COND_WAIT");          \
  98     } STMT_END
  99 #define COND_DESTROY(c)                         \
 100     STMT_START {                                \
 101         if (pthread_cond_destroy((c)))          \
 102             croak("panic: COND_DESTROY");       \
 103     } STMT_END
 104 #endif /* COND_INIT */
 105
 106 /* DETACH(t) must only be called while holding t->mutex */
 107 #ifndef DETACH
 108 #define DETACH(t)                               \
 109     STMT_START {                                \
 110         if (pthread_detach((t)->self)) {        \
 111             MUTEX_UNLOCK(&(t)->mutex);          \
 112             croak("panic: DETACH");             \
 113         }                                       \
 114     } STMT_END
 115 #endif /* DETACH */
 116
 117 #ifndef JOIN
 118 #define JOIN(t, avp)                                    \
 119     STMT_START {                                        \
 120         if (pthread_join((t)->self, (void**)(avp)))     \
 121             croak("panic: pthread_join");               \
 122     } STMT_END
 123 #endif /* JOIN */
 124
 125 #ifndef SET_THR
 126 #define SET_THR(t)                                      \
 127     STMT_START {                                        \
 128         if (pthread_setspecific(PL_thr_key, (void *) (t)))      \
 129             croak("panic: pthread_setspecific");        \
 130     } STMT_END
 131 #endif /* SET_THR */
 132
 133 #ifndef THR
 134 #  ifdef OLD_PTHREADS_API
 135 struct perl_thread *getTHR _((void));
 136 #    define THR getTHR()
 137 #  else
 138 #    define THR ((struct perl_thread *) pthread_getspecific(PL_thr_key))
 139 #  endif /* OLD_PTHREADS_API */
 140 #endif /* THR */
 141
 142 /*
 143  * dTHR is performance-critical. Here, we only do the pthread_get_specific
 144  * if there may be more than one thread in existence, otherwise we get thr
 145  * from thrsv which is cached in the per-interpreter structure.
 146  * Systems with very fast pthread_get_specific (which should be all systems
 147  * but unfortunately isn't) may wish to simplify to "...*thr = THR".
 148  */
 149 #ifndef dTHR
 150 #  define dTHR \
 151     struct perl_thread *thr = PL_threadnum? THR : (struct perl_thread*)SvPVX(PL_thrsv)
 152 #endif /* dTHR */
 153
 154 #ifndef INIT_THREADS
 155 #  ifdef NEED_PTHREAD_INIT
 156 #    define INIT_THREADS pthread_init()
 157 #  else
 158 #    define INIT_THREADS NOOP
 159 #  endif
 160 #endif
 161
 162 /* Accessor for per-thread SVs */
 163 #define THREADSV(i) (thr->threadsvp[i])
 164
 165 /*
 166  * LOCK_SV_MUTEX and UNLOCK_SV_MUTEX are performance-critical. Here, we
 167  * try only locking them if there may be more than one thread in existence.
 168  * Systems with very fast mutexes (and/or slow conditionals) may wish to
 169  * remove the "if (threadnum) ..." test.
 170  */
 171 #define LOCK_SV_MUTEX                           \
 172     STMT_START {                                \
 173         if (PL_threadnum)                       \
 174             MUTEX_LOCK(&PL_sv_mutex);           \
 175     } STMT_END
 176
 177 #define UNLOCK_SV_MUTEX                         \
 178     STMT_START {                                \
 179         if (PL_threadnum)                       \
 180             MUTEX_UNLOCK(&PL_sv_mutex);         \
 181     } STMT_END
 182
 183 /* Likewise for strtab_mutex */
 184 #define LOCK_STRTAB_MUTEX                       \
 185     STMT_START {                                \
 186         if (PL_threadnum)                       \
 187             MUTEX_LOCK(&PL_strtab_mutex);       \
 188     } STMT_END
 189
 190 #define UNLOCK_STRTAB_MUTEX                     \
 191     STMT_START {                                \
 192         if (PL_threadnum)                       \
 193             MUTEX_UNLOCK(&PL_strtab_mutex);     \
 194     } STMT_END
 195
 196 #ifndef THREAD_RET_TYPE
 197 #  define THREAD_RET_TYPE       void *
 198 #  define THREAD_RET_CAST(p)    ((void *)(p))
 199 #endif /* THREAD_RET */
 200
 201
 202 /* Values and macros for thr->flags */
 203 #define THRf_STATE_MASK 7
 204 #define THRf_R_JOINABLE 0
 205 #define THRf_R_JOINED   1
 206 #define THRf_R_DETACHED 2
 207 #define THRf_ZOMBIE     3
 208 #define THRf_DEAD       4
 209
 210 #define THRf_DID_DIE    8
 211
 212 /* ThrSTATE(t) and ThrSETSTATE(t) must only be called while holding t->mutex */
 213 #define ThrSTATE(t) ((t)->flags & THRf_STATE_MASK)
 214 #define ThrSETSTATE(t, s) STMT_START {          \
 215         (t)->flags &= ~THRf_STATE_MASK;         \
 216         (t)->flags |= (s);                      \
 217         DEBUG_S(PerlIO_printf(PerlIO_stderr(),  \
 218                               "thread %p set to state %d\n", (t), (s))); \
 219     } STMT_END
 220
 221 typedef struct condpair {
 222     perl_mutex  mutex;          /* Protects all other fields */
 223     perl_cond   owner_cond;     /* For when owner changes at all */
 224     perl_cond   cond;           /* For cond_signal and cond_broadcast */
 225     Thread      owner;          /* Currently owning thread */
 226 } condpair_t;
 227
 228 #define MgMUTEXP(mg) (&((condpair_t *)(mg->mg_ptr))->mutex)
 229 #define MgOWNERCONDP(mg) (&((condpair_t *)(mg->mg_ptr))->owner_cond)
 230 #define MgCONDP(mg) (&((condpair_t *)(mg->mg_ptr))->cond)
 231 #define MgOWNER(mg) ((condpair_t *)(mg->mg_ptr))->owner
 232
 233 #else
 234 /* USE_THREADS is not defined */
 235 #define MUTEX_LOCK(m)
 236 #define MUTEX_UNLOCK(m)
 237 #define MUTEX_INIT(m)
 238 #define MUTEX_DESTROY(m)
 239 #define COND_INIT(c)
 240 #define COND_SIGNAL(c)
 241 #define COND_BROADCAST(c)
 242 #define COND_WAIT(c, m)
 243 #define COND_DESTROY(c)
 244 #define LOCK_SV_MUTEX
 245 #define UNLOCK_SV_MUTEX
 246 #define LOCK_STRTAB_MUTEX
 247 #define UNLOCK_STRTAB_MUTEX
 248
 249 #define THR
 250 /* Rats: if dTHR is just blank then the subsequent ";" throws an error */
 251 #ifdef WIN32
 252 #define dTHR extern int Perl___notused
 253 #else
 254 #define dTHR extern int errno
 255 #endif
 256 #endif /* USE_THREADS */