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 (&err)
  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_key_create(k,d) pthread_keycreate(k,(pthread_destructor_t)(d))
  29 #      define pthread_mutexattr_init(a) pthread_mutexattr_create(a)
  30 #      define pthread_mutexattr_settype(a,t) pthread_mutexattr_setkind_np(a,t)
  31 #    endif
  32 #    if defined(DJGPP) || defined(__OPEN_VM)
  33 #      define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_attr_setdetachstate(a,&(s))
  34 #      define YIELD pthread_yield(NULL)
  35 #    endif
  36 #    if defined(DJGPP) || defined(VMS)
  37 #      define PTHREAD_CREATE(t,a,s,d) pthread_create(t,a,s,d)
  38 #    endif
  39 #  endif
  40 #  ifndef VMS
  41 #    define pthread_mutexattr_default NULL
  42 #    define pthread_condattr_default  NULL
  43 #  endif
  44 #endif
  45
  46 #ifndef PTHREAD_CREATE
  47 /* You are not supposed to pass NULL as the 2nd arg of PTHREAD_CREATE(). */
  48 #  define PTHREAD_CREATE(t,a,s,d) pthread_create(t,&(a),s,d)
  49 #endif
  50
  51 #ifndef PTHREAD_ATTR_SETDETACHSTATE
  52 #  define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_attr_setdetachstate(a,s)
  53 #endif
  54
  55 #ifndef YIELD
  56 #  ifdef SCHED_YIELD
  57 #    define YIELD SCHED_YIELD
  58 #  else
  59 #    ifdef HAS_SCHED_YIELD
  60 #      define YIELD sched_yield()
  61 #    else
  62 #      ifdef HAS_PTHREAD_YIELD
  63     /* pthread_yield(NULL) platforms are expected
  64      * to have #defined YIELD for themselves. */
  65 #        define YIELD pthread_yield()
  66 #      endif
  67 #    endif
  68 #  endif
  69 #endif
  70
  71 #ifdef PTHREADS_CREATED_JOINABLE
  72 #  define ATTR_JOINABLE PTHREAD_CREATE_JOINABLE
  73 #else
  74 #  ifdef PTHREAD_CREATE_UNDETACHED
  75 #    define ATTR_JOINABLE PTHREAD_CREATE_UNDETACHED
  76 #  else
  77 #    ifdef __UNDETACHED
  78 #      define ATTR_JOINABLE __UNDETACHED
  79 #    endif
  80 #  endif
  81 #endif
  82
  83 #ifndef MUTEX_INIT
  84 #define MUTEX_INIT(m)                                           \
  85     STMT_START {                                                \
  86         if (pthread_mutex_init((m), pthread_mutexattr_default)) \
  87             croak("panic: MUTEX_INIT");                         \
  88     } STMT_END
  89 #define MUTEX_LOCK(m)                           \
  90     STMT_START {                                \
  91         if (pthread_mutex_lock((m)))            \
  92             croak("panic: MUTEX_LOCK");         \
  93     } STMT_END
  94 #define MUTEX_UNLOCK(m)                         \
  95     STMT_START {                                \
  96         if (pthread_mutex_unlock((m)))          \
  97             croak("panic: MUTEX_UNLOCK");       \
  98     } STMT_END
  99 #define MUTEX_DESTROY(m)                        \
 100     STMT_START {                                \
 101         if (pthread_mutex_destroy((m)))         \
 102             croak("panic: MUTEX_DESTROY");      \
 103     } STMT_END
 104 #endif /* MUTEX_INIT */
 105
 106 #ifndef COND_INIT
 107 #define COND_INIT(c)                                            \
 108     STMT_START {                                                \
 109         if (pthread_cond_init((c), pthread_condattr_default))   \
 110             croak("panic: COND_INIT");                          \
 111     } STMT_END
 112 #define COND_SIGNAL(c)                          \
 113     STMT_START {                                \
 114         if (pthread_cond_signal((c)))           \
 115             croak("panic: COND_SIGNAL");        \
 116     } STMT_END
 117 #define COND_BROADCAST(c)                       \
 118     STMT_START {                                \
 119         if (pthread_cond_broadcast((c)))        \
 120             croak("panic: COND_BROADCAST");     \
 121     } STMT_END
 122 #define COND_WAIT(c, m)                         \
 123     STMT_START {                                \
 124         if (pthread_cond_wait((c), (m)))        \
 125             croak("panic: COND_WAIT");          \
 126     } STMT_END
 127 #define COND_DESTROY(c)                         \
 128     STMT_START {                                \
 129         if (pthread_cond_destroy((c)))          \
 130             croak("panic: COND_DESTROY");       \
 131     } STMT_END
 132 #endif /* COND_INIT */
 133
 134 /* DETACH(t) must only be called while holding t->mutex */
 135 #ifndef DETACH
 136 #define DETACH(t)                               \
 137     STMT_START {                                \
 138         if (pthread_detach((t)->self)) {        \
 139             MUTEX_UNLOCK(&(t)->mutex);          \
 140             croak("panic: DETACH");             \
 141         }                                       \
 142     } STMT_END
 143 #endif /* DETACH */
 144
 145 #ifndef JOIN
 146 #define JOIN(t, avp)                                    \
 147     STMT_START {                                        \
 148         if (pthread_join((t)->self, (void**)(avp)))     \
 149             croak("panic: pthread_join");               \
 150     } STMT_END
 151 #endif /* JOIN */
 152
 153 #ifndef SET_THR
 154 #define SET_THR(t)                                      \
 155     STMT_START {                                        \
 156         if (pthread_setspecific(PL_thr_key, (void *) (t)))      \
 157             croak("panic: pthread_setspecific");        \
 158     } STMT_END
 159 #endif /* SET_THR */
 160
 161 #ifndef THR
 162 #define THR ((struct perl_thread *) pthread_getspecific(PL_thr_key))
 163 #endif
 164
 165 /*
 166  * dTHR is performance-critical. Here, we only do the pthread_get_specific
 167  * if there may be more than one thread in existence, otherwise we get thr
 168  * from thrsv which is cached in the per-interpreter structure.
 169  * Systems with very fast pthread_get_specific (which should be all systems
 170  * but unfortunately isn't) may wish to simplify to "...*thr = THR".
 171  */
 172 #ifndef dTHR
 173 #  define dTHR \
 174     struct perl_thread *thr = PL_threadnum? THR : (struct perl_thread*)SvPVX(PL_thrsv)
 175 #endif /* dTHR */
 176
 177 #ifndef INIT_THREADS
 178 #  ifdef NEED_PTHREAD_INIT
 179 #    define INIT_THREADS pthread_init()
 180 #  else
 181 #    define INIT_THREADS NOOP
 182 #  endif
 183 #endif
 184
 185 /* Accessor for per-thread SVs */
 186 #define THREADSV(i) (thr->threadsvp[i])
 187
 188 /*
 189  * LOCK_SV_MUTEX and UNLOCK_SV_MUTEX are performance-critical. Here, we
 190  * try only locking them if there may be more than one thread in existence.
 191  * Systems with very fast mutexes (and/or slow conditionals) may wish to
 192  * remove the "if (threadnum) ..." test.
 193  */
 194 #define LOCK_SV_MUTEX                           \
 195     STMT_START {                                \
 196         if (PL_threadnum)                       \
 197             MUTEX_LOCK(&PL_sv_mutex);           \
 198     } STMT_END
 199
 200 #define UNLOCK_SV_MUTEX                         \
 201     STMT_START {                                \
 202         if (PL_threadnum)                       \
 203             MUTEX_UNLOCK(&PL_sv_mutex);         \
 204     } STMT_END
 205
 206 /* Likewise for strtab_mutex */
 207 #define LOCK_STRTAB_MUTEX                       \
 208     STMT_START {                                \
 209         if (PL_threadnum)                       \
 210             MUTEX_LOCK(&PL_strtab_mutex);       \
 211     } STMT_END
 212
 213 #define UNLOCK_STRTAB_MUTEX                     \
 214     STMT_START {                                \
 215         if (PL_threadnum)                       \
 216             MUTEX_UNLOCK(&PL_strtab_mutex);     \
 217     } STMT_END
 218
 219 #ifndef THREAD_RET_TYPE
 220 #  define THREAD_RET_TYPE       void *
 221 #  define THREAD_RET_CAST(p)    ((void *)(p))
 222 #endif /* THREAD_RET */
 223
 224
 225 /* Values and macros for thr->flags */
 226 #define THRf_STATE_MASK 7
 227 #define THRf_R_JOINABLE 0
 228 #define THRf_R_JOINED   1
 229 #define THRf_R_DETACHED 2
 230 #define THRf_ZOMBIE     3
 231 #define THRf_DEAD       4
 232
 233 #define THRf_DID_DIE    8
 234
 235 /* ThrSTATE(t) and ThrSETSTATE(t) must only be called while holding t->mutex */
 236 #define ThrSTATE(t) ((t)->flags & THRf_STATE_MASK)
 237 #define ThrSETSTATE(t, s) STMT_START {          \
 238         (t)->flags &= ~THRf_STATE_MASK;         \
 239         (t)->flags |= (s);                      \
 240         DEBUG_S(PerlIO_printf(PerlIO_stderr(),  \
 241                               "thread %p set to state %d\n", (t), (s))); \
 242     } STMT_END
 243
 244 typedef struct condpair {
 245     perl_mutex  mutex;          /* Protects all other fields */
 246     perl_cond   owner_cond;     /* For when owner changes at all */
 247     perl_cond   cond;           /* For cond_signal and cond_broadcast */
 248     Thread      owner;          /* Currently owning thread */
 249 } condpair_t;
 250
 251 #define MgMUTEXP(mg) (&((condpair_t *)(mg->mg_ptr))->mutex)
 252 #define MgOWNERCONDP(mg) (&((condpair_t *)(mg->mg_ptr))->owner_cond)
 253 #define MgCONDP(mg) (&((condpair_t *)(mg->mg_ptr))->cond)
 254 #define MgOWNER(mg) ((condpair_t *)(mg->mg_ptr))->owner
 255
 256 #else
 257 /* USE_THREADS is not defined */
 258 #define MUTEX_LOCK(m)
 259 #define MUTEX_UNLOCK(m)
 260 #define MUTEX_INIT(m)
 261 #define MUTEX_DESTROY(m)
 262 #define COND_INIT(c)
 263 #define COND_SIGNAL(c)
 264 #define COND_BROADCAST(c)
 265 #define COND_WAIT(c, m)
 266 #define COND_DESTROY(c)
 267 #define LOCK_SV_MUTEX
 268 #define UNLOCK_SV_MUTEX
 269 #define LOCK_STRTAB_MUTEX
 270 #define UNLOCK_STRTAB_MUTEX
 271
 272 #define THR
 273 /* Rats: if dTHR is just blank then the subsequent ";" throws an error */
 274 #ifdef WIN32
 275 #define dTHR extern int Perl___notused
 276 #else
 277 #define dTHR extern int errno
 278 #endif
 279 #endif /* USE_THREADS */