summaryrefslogtreecommitdiff
path: root/gnu/usr.bin/perl/thread.h
blob: 474c2b43b66057776127035a97cc444f1591f9dc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
/*    thread.h
 *
 *    Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
 *    by Larry Wall and others
 *
 *    You may distribute under the terms of either the GNU General Public
 *    License or the Artistic License, as specified in the README file.
 *
 */

#if defined(USE_ITHREADS)

#if defined(VMS)
#include <builtins.h>
#endif

#ifdef WIN32
#  include <win32thread.h>
#else
#  ifdef OLD_PTHREADS_API /* Here be dragons. */
#    define DETACH(t) \
    STMT_START {						\
        int _eC_;						\
        if ((_eC_ = pthread_detach(&(t)->self))) {		\
            MUTEX_UNLOCK(&(t)->mutex);				\
            Perl_croak_nocontext("panic: DETACH (%d) [%s:%d]",	\
                                 _eC_, __FILE__, __LINE__);	\
        }							\
    } STMT_END

#    define PERL_GET_CONTEXT	Perl_get_context()
#    define PERL_SET_CONTEXT(t)	Perl_set_context((void*)t)

#    define PTHREAD_GETSPECIFIC_INT
#    ifdef OEMVS
#      define pthread_addr_t void *
#      define pthread_create(t,a,s,d)        pthread_create(t,&(a),s,d)
#      define pthread_keycreate              pthread_key_create
#    endif
#    ifdef VMS
#      define pthread_attr_init(a) pthread_attr_create(a)
#      define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_setdetach_np(a,s)
#      define PTHREAD_CREATE(t,a,s,d) pthread_create(t,a,s,d)
#      define pthread_key_create(k,d) pthread_keycreate(k,(pthread_destructor_t)(d))
#      define pthread_mutexattr_init(a) pthread_mutexattr_create(a)
#      define pthread_mutexattr_settype(a,t) pthread_mutexattr_setkind_np(a,t)
#    endif
#    if defined(__hpux) && defined(__ux_version) && __ux_version <= 1020
#      define pthread_attr_init(a) pthread_attr_create(a)
       /* XXX pthread_setdetach_np() missing in DCE threads on HP-UX 10.20 */
#      define PTHREAD_ATTR_SETDETACHSTATE(a,s)	(0)
#      define PTHREAD_CREATE(t,a,s,d) pthread_create(t,a,s,d)
#      define pthread_key_create(k,d) pthread_keycreate(k,(pthread_destructor_t)(d))
#      define pthread_mutexattr_init(a) pthread_mutexattr_create(a)
#      define pthread_mutexattr_settype(a,t) pthread_mutexattr_setkind_np(a,t)
#    endif
#    if defined(OEMVS)
#      define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_attr_setdetachstate(a,&(s))
#      define YIELD pthread_yield(NULL)
#    endif
#  endif
#  if !defined(__hpux) || !defined(__ux_version) || __ux_version > 1020
#    define pthread_mutexattr_default NULL
#    define pthread_condattr_default  NULL
#  endif
#endif

#ifndef PTHREAD_CREATE
/* You are not supposed to pass NULL as the 2nd arg of PTHREAD_CREATE(). */
#  define PTHREAD_CREATE(t,a,s,d) pthread_create(t,&(a),s,d)
#endif

#ifndef PTHREAD_ATTR_SETDETACHSTATE
#  define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_attr_setdetachstate(a,s)
#endif

#ifndef PTHREAD_CREATE_JOINABLE
#  ifdef OLD_PTHREAD_CREATE_JOINABLE
#    define PTHREAD_CREATE_JOINABLE OLD_PTHREAD_CREATE_JOINABLE
#  else
#    define PTHREAD_CREATE_JOINABLE 0 /* Panic?  No, guess. */
#  endif
#endif

#ifdef __VMS
  /* Default is 1024 on VAX, 8192 otherwise */
#  ifdef __ia64
#    define THREAD_CREATE_NEEDS_STACK (48*1024)
#  else
#    define THREAD_CREATE_NEEDS_STACK (32*1024)
#  endif
#endif

#ifdef I_MACH_CTHREADS

/* cthreads interface */

/* #include <mach/cthreads.h> is in perl.h #ifdef I_MACH_CTHREADS */

#define MUTEX_INIT(m) \
    STMT_START {						\
        *m = mutex_alloc();					\
        if (*m) {						\
            mutex_init(*m);					\
        } else {						\
            Perl_croak_nocontext("panic: MUTEX_INIT [%s:%d]",	\
                                 __FILE__, __LINE__);		\
        }							\
    } STMT_END

#define MUTEX_LOCK(m)			mutex_lock(*m)
#define MUTEX_UNLOCK(m)			mutex_unlock(*m)
#define MUTEX_DESTROY(m) \
    STMT_START {						\
        mutex_free(*m);						\
        *m = 0;							\
    } STMT_END

#define COND_INIT(c) \
    STMT_START {						\
        *c = condition_alloc();					\
        if (*c) {						\
            condition_init(*c);					\
        }							\
        else {							\
            Perl_croak_nocontext("panic: COND_INIT [%s:%d]",	\
                                 __FILE__, __LINE__);		\
        }							\
    } STMT_END

#define COND_SIGNAL(c)		condition_signal(*c)
#define COND_BROADCAST(c)	condition_broadcast(*c)
#define COND_WAIT(c, m)		condition_wait(*c, *m)
#define COND_DESTROY(c) \
    STMT_START {						\
        condition_free(*c);					\
        *c = 0;							\
    } STMT_END

#define THREAD_RET_TYPE		any_t

#define DETACH(t)		cthread_detach(t->self)
#define JOIN(t, avp)		(*(avp) = MUTABLE_AV(cthread_join(t->self)))

#define PERL_SET_CONTEXT(t)	cthread_set_data(cthread_self(), t)
#define PERL_GET_CONTEXT	cthread_data(cthread_self())

#define INIT_THREADS		cthread_init()
#define YIELD			cthread_yield()
#define ALLOC_THREAD_KEY	NOOP
#define FREE_THREAD_KEY		NOOP
#define SET_THREAD_SELF(thr)	(thr->self = cthread_self())

#endif /* I_MACH_CTHREADS */

#ifndef YIELD
#  ifdef SCHED_YIELD
#    define YIELD SCHED_YIELD
#  elif defined(HAS_SCHED_YIELD)
#    define YIELD sched_yield()
#  elif defined(HAS_PTHREAD_YIELD)
    /* pthread_yield(NULL) platforms are expected
     * to have #defined YIELD for themselves. */
#    define YIELD pthread_yield()
#  endif
#endif

#ifdef __hpux
#  define MUTEX_INIT_NEEDS_MUTEX_ZEROED
#endif

#ifndef MUTEX_INIT

#  ifdef MUTEX_INIT_NEEDS_MUTEX_ZEROED
    /* Temporary workaround, true bug is deeper. --jhi 1999-02-25 */
#    define MUTEX_INIT(m) \
    STMT_START {                                                    \
        int _eC_;                                                   \
        Zero((m), 1, perl_mutex);                                   \
        if ((_eC_ = pthread_mutex_init((m), pthread_mutexattr_default)))\
            Perl_croak_nocontext("panic: MUTEX_INIT (%d) [%s:%d]",  \
                                 _eC_, __FILE__, __LINE__);         \
    } STMT_END
#  else
#    define MUTEX_INIT(m) \
    STMT_START {						\
        int _eC_;						\
        if ((_eC_ = pthread_mutex_init((m), pthread_mutexattr_default))) \
            Perl_croak_nocontext("panic: MUTEX_INIT (%d) [%s:%d]", \
                                 _eC_, __FILE__, __LINE__);     \
    } STMT_END
#  endif

#  ifdef PERL_TSA_ACTIVE
#    define perl_pthread_mutex_lock(m) perl_tsa_mutex_lock(m)
#    define perl_pthread_mutex_unlock(m) perl_tsa_mutex_unlock(m)
#  else
#    define perl_pthread_mutex_lock(m) pthread_mutex_lock(m)
#    define perl_pthread_mutex_unlock(m) pthread_mutex_unlock(m)
#  endif

#  define MUTEX_LOCK(m)                                         \
    STMT_START {						\
        dSAVE_ERRNO;                                            \
        int _eC_;						\
        if ((_eC_ = perl_pthread_mutex_lock((m))))		\
            Perl_croak_nocontext("panic: MUTEX_LOCK (%d) [%s:%d]",\
                                 _eC_, __FILE__, __LINE__);	\
        RESTORE_ERRNO;                                          \
    } STMT_END

#  define MUTEX_UNLOCK(m)                                       \
    STMT_START {						\
        dSAVE_ERRNO; /* Shouldn't be necessary as panics if fails */\
        int _eC_;						\
        if ((_eC_ = perl_pthread_mutex_unlock((m)))) {          \
            Perl_croak_nocontext(                               \
                            "panic: MUTEX_UNLOCK (%d) [%s:%d]", \
                                 _eC_, __FILE__, __LINE__);	\
        }                                                       \
        RESTORE_ERRNO;                                          \
    } STMT_END

#  define MUTEX_DESTROY(m)                                                  \
    STMT_START {						            \
        int _eC_;						            \
        if ((_eC_ = pthread_mutex_destroy((m)))) {                          \
            dTHX;                                                           \
            if (PL_phase != PERL_PHASE_DESTRUCT) {                          \
                Perl_croak_nocontext("panic: MUTEX_DESTROY (%d) [%s:%d]",   \
                                    _eC_, __FILE__, __LINE__);	            \
            }                                                               \
        }                                                                   \
    } STMT_END
#endif /* MUTEX_INIT */

#ifndef COND_INIT
#  define COND_INIT(c) \
    STMT_START {						\
        int _eC_;						\
        if ((_eC_ = pthread_cond_init((c), pthread_condattr_default)))	\
            Perl_croak_nocontext("panic: COND_INIT (%d) [%s:%d]",	\
                                 _eC_, __FILE__, __LINE__);	\
    } STMT_END

#  define COND_SIGNAL(c) \
    STMT_START {						\
        int _eC_;						\
        if ((_eC_ = pthread_cond_signal((c))))			\
            Perl_croak_nocontext("panic: COND_SIGNAL (%d) [%s:%d]",	\
                                 _eC_, __FILE__, __LINE__);	\
    } STMT_END

#  define COND_BROADCAST(c) \
    STMT_START {						\
        int _eC_;						\
        if ((_eC_ = pthread_cond_broadcast((c))))		\
            Perl_croak_nocontext("panic: COND_BROADCAST (%d) [%s:%d]",	\
                                 _eC_, __FILE__, __LINE__);	\
    } STMT_END

#  define COND_WAIT(c, m) \
    STMT_START {						\
        int _eC_;						\
        if ((_eC_ = pthread_cond_wait((c), (m))))		\
            Perl_croak_nocontext("panic: COND_WAIT (%d) [%s:%d]",	\
                                 _eC_, __FILE__, __LINE__);	\
    } STMT_END

#  define COND_DESTROY(c) \
    STMT_START {						            \
        int _eC_;						            \
        if ((_eC_ = pthread_cond_destroy((c)))) {                           \
            dTHX;                                                           \
            if (PL_phase != PERL_PHASE_DESTRUCT) {                          \
                Perl_croak_nocontext("panic: COND_DESTROY (%d) [%s:%d]",    \
                                    _eC_, __FILE__, __LINE__);	            \
            }                                                               \
        }                                                                   \
    } STMT_END
#endif /* COND_INIT */

#if defined(MUTEX_LOCK) && defined(MUTEX_UNLOCK)                \
 && defined(COND_SIGNAL) && defined(COND_WAIT)

/* These emulate native many-reader/1-writer locks.
 * Basically a locking reader just locks the semaphore long enough to increment
 * a counter; and similarly decrements it when when through.  Any writer will
 * run only when the count of readers is 0.  That is because it blocks on that
 * semaphore (doing a COND_WAIT) until it gets control of it, which won't
 * happen unless the count becomes 0.  ALL readers and other writers are then
 * blocked until it releases the semaphore.  The reader whose unlocking causes
 * the count to become 0 signals any waiting writers, and the system guarantees
 * that only one gets control at a time */

#  define PERL_READ_LOCK(mutex)                                     \
    STMT_START {                                                    \
        MUTEX_LOCK(&(mutex)->lock);                                 \
        (mutex)->readers_count++;                                   \
        MUTEX_UNLOCK(&(mutex)->lock);                               \
    } STMT_END

#  define PERL_READ_UNLOCK(mutex)                                   \
    STMT_START {                                                    \
        MUTEX_LOCK(&(mutex)->lock);                                 \
        (mutex)->readers_count--;                                   \
        if ((mutex)->readers_count <= 0) {                          \
            assert((mutex)->readers_count == 0);                    \
            COND_SIGNAL(&(mutex)->wakeup);                          \
            (mutex)->readers_count = 0;                             \
        }                                                           \
        MUTEX_UNLOCK(&(mutex)->lock);                               \
    } STMT_END

#  define PERL_WRITE_LOCK(mutex)                                    \
    STMT_START {                                                    \
        MUTEX_LOCK(&(mutex)->lock);                                 \
        do {                                                        \
            if ((mutex)->readers_count <= 0) {                      \
                assert((mutex)->readers_count == 0);                \
                (mutex)->readers_count = 0;                         \
                break;                                              \
            }                                                       \
            COND_WAIT(&(mutex)->wakeup, &(mutex)->lock);            \
        }                                                           \
        while (1);                                                  \
                                                                    \
        /* Here, the mutex is locked, with no readers */            \
    } STMT_END

#  define PERL_WRITE_UNLOCK(mutex)                                  \
    STMT_START {                                                    \
        COND_SIGNAL(&(mutex)->wakeup);                              \
        MUTEX_UNLOCK(&(mutex)->lock);                               \
    } STMT_END

#  define PERL_RW_MUTEX_INIT(mutex)                                 \
    STMT_START {                                                    \
        MUTEX_INIT(&(mutex)->lock);                                 \
        COND_INIT(&(mutex)->wakeup);                                \
        (mutex)->readers_count = 0;                                 \
    } STMT_END

#  define PERL_RW_MUTEX_DESTROY(mutex)                              \
    STMT_START {                                                    \
        COND_DESTROY(&(mutex)->wakeup);                             \
        MUTEX_DESTROY(&(mutex)->lock);                              \
    } STMT_END

#endif

/* DETACH(t) must only be called while holding t->mutex */
#ifndef DETACH
#  define DETACH(t) \
    STMT_START {						\
        int _eC_;						\
        if ((_eC_ = pthread_detach((t)->self))) {		\
            MUTEX_UNLOCK(&(t)->mutex);				\
            Perl_croak_nocontext("panic: DETACH (%d) [%s:%d]",	\
                                 _eC_, __FILE__, __LINE__);	\
        }							\
    } STMT_END
#endif /* DETACH */

#ifndef JOIN
#  define JOIN(t, avp) \
    STMT_START {						\
        int _eC_;						\
        if ((_eC_ = pthread_join((t)->self, (void**)(avp))))	\
            Perl_croak_nocontext("panic: pthread_join (%d) [%s:%d]",	\
                                 _eC_, __FILE__, __LINE__);	\
    } STMT_END
#endif /* JOIN */

/* Use an unchecked fetch of thread-specific data instead of a checked one.
 * It would fail if the key were bogus, but if the key were bogus then
 * Really Bad Things would be happening anyway. --dan */
#if (defined(__ALPHA) && (__VMS_VER >= 70000000)) || \
    (defined(__alpha) && defined(__osf__) && !defined(__GNUC__)) /* Available only on >= 4.0 */
#  define HAS_PTHREAD_UNCHECKED_GETSPECIFIC_NP /* Configure test needed */
#endif

#ifdef HAS_PTHREAD_UNCHECKED_GETSPECIFIC_NP
#  define PTHREAD_GETSPECIFIC(key) pthread_unchecked_getspecific_np(key)
#else
#    define PTHREAD_GETSPECIFIC(key) pthread_getspecific(key)
#endif

#if defined(PERL_THREAD_LOCAL) && !defined(PERL_GET_CONTEXT) && !defined(PERL_SET_CONTEXT) && !defined(__cplusplus)
/* Use C11 thread-local storage, where possible.
 * Frustratingly we can't use it for C++ extensions, C++ and C disagree on the
 * syntax used for thread local storage, meaning that the working token that
 * Configure probed for C turns out to be a compiler error on C++. Great.
 * (Well, unless one or both is supporting non-standard syntax as an extension)
 * As Configure doesn't have a way to probe for C++ dialects, we just take the
 * safe option and do the same as 5.34.0 and earlier - use pthreads on C++.
 * Of course, if C++ XS extensions really want to avoid *all* this overhead,
 * they should #define PERL_NO_GET_CONTEXT and pass aTHX/aTHX_ explicitly) */
#  define PERL_USE_THREAD_LOCAL
extern PERL_THREAD_LOCAL void *PL_current_context;

#  define PERL_GET_CONTEXT        PL_current_context

/* We must also call pthread_setspecific() always, as C++ code has to read it
 * with pthreads (the #else side just below) */

#  define PERL_SET_CONTEXT(t)                                               \
    STMT_START {                                                            \
        int _eC_;                                                           \
        if ((_eC_ = pthread_setspecific(PL_thr_key,                         \
                                        PL_current_context = (void *)(t)))) \
            Perl_croak_nocontext("panic: pthread_setspecific (%d) [%s:%d]", \
                                 _eC_, __FILE__, __LINE__);                 \
        PERL_SET_NON_tTHX_CONTEXT(t);                                       \
    } STMT_END

#else
/* else fall back to pthreads */

#  ifndef PERL_GET_CONTEXT
#    define PERL_GET_CONTEXT	PTHREAD_GETSPECIFIC(PL_thr_key)
#  endif

/* For C++ extensions built on a system where the C compiler provides thread
 * local storage that call PERL_SET_CONTEXT() also need to set
 * PL_current_context, so need to call into C code to do this.
 * To avoid exploding code complexity, do this also on C platforms that don't
 * support thread local storage. PERL_SET_CONTEXT is not called that often. */

#  ifndef PERL_SET_CONTEXT
#    define PERL_SET_CONTEXT(t) Perl_set_context((void*)t)
#  endif /* PERL_SET_CONTEXT */
#endif /* PERL_THREAD_LOCAL */

#ifndef INIT_THREADS
#  ifdef NEED_PTHREAD_INIT
#    define INIT_THREADS pthread_init()
#  endif
#endif

#ifndef ALLOC_THREAD_KEY
#  define ALLOC_THREAD_KEY \
    STMT_START {						\
        if (pthread_key_create(&PL_thr_key, 0)) {		\
            PERL_UNUSED_RESULT(write(2, STR_WITH_LEN("panic: pthread_key_create failed\n"))); \
            exit(1);						\
        }							\
    } STMT_END
#endif

#ifndef FREE_THREAD_KEY
#  define FREE_THREAD_KEY \
    STMT_START {						\
        pthread_key_delete(PL_thr_key);				\
    } STMT_END
#endif

#ifndef PTHREAD_ATFORK
#  ifdef HAS_PTHREAD_ATFORK
#    define PTHREAD_ATFORK(prepare,parent,child)		\
        pthread_atfork(prepare,parent,child)
#  else
#    define PTHREAD_ATFORK(prepare,parent,child)		\
        NOOP
#  endif
#endif

#ifndef THREAD_RET_TYPE
#  define THREAD_RET_TYPE	void *
#endif /* THREAD_RET */

#  define LOCK_DOLLARZERO_MUTEX		MUTEX_LOCK(&PL_dollarzero_mutex)
#  define UNLOCK_DOLLARZERO_MUTEX	MUTEX_UNLOCK(&PL_dollarzero_mutex)

#endif /* USE_ITHREADS */

#ifndef MUTEX_LOCK
#  define MUTEX_LOCK(m)           NOOP
#endif

#ifndef MUTEX_UNLOCK
#  define MUTEX_UNLOCK(m)         NOOP
#endif

#ifndef MUTEX_INIT
#  define MUTEX_INIT(m)           NOOP
#endif

#ifndef MUTEX_DESTROY
#  define MUTEX_DESTROY(m)        NOOP
#endif

#ifndef COND_INIT
#  define COND_INIT(c)            NOOP
#endif

#ifndef COND_SIGNAL
#  define COND_SIGNAL(c)          NOOP
#endif

#ifndef COND_BROADCAST
#  define COND_BROADCAST(c)       NOOP
#endif

#ifndef COND_WAIT
#  define COND_WAIT(c, m)         NOOP
#endif

#ifndef COND_DESTROY
#  define COND_DESTROY(c)         NOOP
#endif

#ifndef PERL_READ_LOCK
#  define PERL_READ_LOCK          NOOP
#  define PERL_READ_UNLOCK        NOOP
#  define PERL_WRITE_LOCK         NOOP
#  define PERL_WRITE_UNLOCK       NOOP
#  define PERL_RW_MUTEX_INIT      NOOP
#  define PERL_RW_MUTEX_DESTROY   NOOP
#endif

#ifndef LOCK_DOLLARZERO_MUTEX
#  define LOCK_DOLLARZERO_MUTEX   NOOP
#endif

#ifndef UNLOCK_DOLLARZERO_MUTEX
#  define UNLOCK_DOLLARZERO_MUTEX NOOP
#endif

/* THR, SET_THR, and dTHR are there for compatibility with old versions */
#ifndef THR
#  define THR		PERL_GET_THX
#endif

#ifndef SET_THR
#  define SET_THR(t)	PERL_SET_THX(t)
#endif

#ifndef dTHR
#  define dTHR dNOOP
#endif

#ifndef INIT_THREADS
#  define INIT_THREADS NOOP
#endif

/*
 * ex: set ts=8 sts=4 sw=4 et:
 */