1 #include "private/gc_priv.h"
3 #if defined(GC_WIN32_THREADS)
7 #ifdef THREAD_LOCAL_ALLOC
8 # include "private/thread_local_alloc.h"
9 #endif /* THREAD_LOCAL_ALLOC */
11 /* Allocation lock declarations. */
12 #if !defined(USE_PTHREAD_LOCKS)
14 __declspec(dllexport
) CRITICAL_SECTION GC_allocate_ml
;
16 CRITICAL_SECTION GC_allocate_ml
;
18 DWORD GC_lock_holder
= NO_THREAD
;
19 /* Thread id for current holder of allocation lock */
21 pthread_mutex_t GC_allocate_ml
= PTHREAD_MUTEX_INITIALIZER
;
22 unsigned long GC_lock_holder
= NO_THREAD
;
28 /* GC_DLL should not normally be defined, especially since we often do turn */
29 /* on THREAD_LOCAL_ALLOC, which is currently incompatible. */
30 /* It might be possible to get GC_DLL and DllMain-based thread registration */
31 /* to work with Cygwin, but if you try you are on your own. */
33 # error GC_DLL untested with Cygwin
36 /* Cygwin-specific forward decls */
37 # undef pthread_create
38 # undef pthread_sigmask
40 # undef pthread_detach
45 # define DEBUG_CYGWIN_THREADS 1
46 # define DEBUG_WIN32_PTHREADS 0
48 # define DEBUG_WIN32_PTHREADS 1
49 # define DEBUG_CYGWIN_THREADS 0
52 # define DEBUG_CYGWIN_THREADS 0
53 # define DEBUG_WIN32_PTHREADS 0
56 void * GC_pthread_start(void * arg
);
57 void GC_thread_exit_proc(void *arg
);
64 # define DEBUG_WIN32_THREADS 1
66 # define DEBUG_WIN32_THREADS 0
71 # undef _beginthreadex
75 # define DEBUG_WIN32_THREADS 1
77 # define DEBUG_WIN32_THREADS 0
80 # include <process.h> /* For _beginthreadex, _endthreadex */
84 #if defined(GC_DLL) && !defined(MSWINCE)
85 static GC_bool GC_win32_dll_threads
= FALSE
;
86 /* This code operates in two distinct modes, depending on */
87 /* the setting of GC_win32_dll_threads. If */
88 /* GC_win32_dll_threads is set, all threads in the process */
89 /* are implicitly registered with the GC by DllMain. */
90 /* No explicit registration is required, and attempts at */
91 /* explicit registration are ignored. This mode is */
92 /* very different from the Posix operation of the collector. */
93 /* In this mode access to the thread table is lock-free. */
94 /* Hence there is a static limit on the number of threads. */
96 /* If GC_win32_dll_threads is FALSE, or the collector is */
97 /* built without GC_DLL defined, things operate in a way */
98 /* that is very similar to Posix platforms, and new threads */
99 /* must be registered with the collector, e.g. by using */
100 /* preprocessor-based interception of the thread primitives. */
101 /* In this case, we use a real data structure for the thread */
102 /* table. Note that there is no equivalent of linker-based */
103 /* call interception, since we don't have ELF-like */
104 /* facilities. The Windows analog appears to be "API */
105 /* hooking", which really seems to be a standard way to */
106 /* do minor binary rewriting (?). I'd prefer not to have */
107 /* the basic collector rely on such facilities, but an */
108 /* optional package that intercepts thread calls this way */
109 /* would probably be nice. */
111 /* GC_win32_dll_threads must be set at initialization time, */
112 /* i.e. before any collector or thread calls. We make it a */
113 /* "dynamic" option only to avoid multiple library versions. */
115 # define GC_win32_dll_threads FALSE
118 /* We have two versions of the thread table. Which one */
119 /* we us depends on whether or not GC_win32_dll_threads */
120 /* is set. Note that before initialization, we don't */
121 /* add any entries to either table, even if DllMain is */
122 /* called. The main thread will be added on */
123 /* initialization. */
125 /* The type of the first argument to InterlockedExchange. */
126 /* Documented to be LONG volatile *, but at least gcc likes */
130 GC_bool GC_thr_initialized
= FALSE
;
132 GC_bool GC_need_to_lock
= FALSE
;
134 static GC_bool parallel_initialized
= FALSE
;
136 void GC_init_parallel(void);
139 /* Turn on GC_win32_dll_threads */
140 GC_API
void GC_use_DllMain(void)
142 # ifdef THREAD_LOCAL_ALLOC
143 ABORT("Cannot use thread local allocation with DllMain-based "
144 "thread registration.");
145 /* Thread-local allocation really wants to lock at thread */
146 /* entry and exit. */
148 GC_ASSERT(!parallel_initialized
);
149 GC_win32_dll_threads
= TRUE
;
152 GC_API
void GC_use_DllMain(void)
154 ABORT("GC not configured as DLL");
158 DWORD GC_main_thread
= 0;
160 struct GC_Thread_Rep
{
162 AO_t tm_in_use
; /* Updated without lock. */
163 /* We assert that unused */
164 /* entries have invalid ids of */
165 /* zero and zero stack fields. */
166 /* Used only with GC_win32_dll_threads. */
167 struct GC_Thread_Rep
* tm_next
;
168 /* Hash table link without */
169 /* GC_win32_dll_threads. */
170 /* More recently allocated threads */
171 /* with a given pthread id come */
172 /* first. (All but the first are */
173 /* guaranteed to be dead, but we may */
174 /* not yet have registered the join.) */
176 # define in_use table_management.tm_in_use
177 # define next table_management.tm_next
180 ptr_t stack_base
; /* The cold end of the stack. */
181 /* 0 ==> entry not valid. */
182 /* !in_use ==> stack_base == 0 */
186 void *status
; /* hold exit value until join in case it's a pointer */
187 pthread_t pthread_id
;
188 short flags
; /* Protected by GC lock. */
189 # define FINISHED 1 /* Thread has exited. */
190 # define DETACHED 2 /* Thread is intended to be detached. */
191 # define KNOWN_FINISHED(t) (((t) -> flags) & FINISHED)
193 # define KNOWN_FINISHED(t) 0
195 # ifdef THREAD_LOCAL_ALLOC
196 struct thread_local_freelists tlfs
;
200 typedef struct GC_Thread_Rep
* GC_thread
;
201 typedef volatile struct GC_Thread_Rep
* GC_vthread
;
204 * We assumed that volatile ==> memory ordering, at least among
205 * volatiles. This code should consistently use atomic_ops.
208 volatile GC_bool GC_please_stop
= FALSE
;
211 * We track thread attachments while the world is supposed to be stopped.
212 * Unfortunately, we can't stop them from starting, since blocking in
213 * DllMain seems to cause the world to deadlock. Thus we have to recover
214 * If we notice this in the middle of marking.
217 AO_t GC_attached_thread
= FALSE
;
218 /* Return TRUE if an thread was attached since we last asked or */
219 /* since GC_attached_thread was explicitly reset. */
220 GC_bool
GC_started_thread_while_stopped(void)
224 if (GC_win32_dll_threads
) {
225 AO_nop_full(); /* Prior heap reads need to complete earlier. */
226 result
= AO_load(&GC_attached_thread
);
228 AO_store(&GC_attached_thread
, FALSE
);
230 return ((GC_bool
)result
);
236 /* Thread table used if GC_win32_dll_threads is set. */
237 /* This is a fixed size array. */
238 /* Since we use runtime conditionals, both versions */
239 /* are always defined. */
241 # define MAX_THREADS 512
243 /* Things may get quite slow for large numbers of threads, */
244 /* since we look them up with sequential search. */
246 volatile struct GC_Thread_Rep dll_thread_table
[MAX_THREADS
];
248 volatile LONG GC_max_thread_index
= 0;
249 /* Largest index in dll_thread_table */
250 /* that was ever used. */
252 /* And now the version used if GC_win32_dll_threads is not set. */
253 /* This is a chained hash table, with much of the code borrowed */
254 /* From the Posix implementation. */
255 # define THREAD_TABLE_SZ 256 /* Must be power of 2 */
256 GC_thread GC_threads
[THREAD_TABLE_SZ
];
259 /* Add a thread to GC_threads. We assume it wasn't already there. */
260 /* Caller holds allocation lock. */
261 /* Unlike the pthreads version, the id field is set by the caller. */
262 GC_thread
GC_new_thread(DWORD id
)
264 word hv
= ((word
)id
) % THREAD_TABLE_SZ
;
266 /* It may not be safe to allocate when we register the first thread. */
267 static struct GC_Thread_Rep first_thread
;
268 static GC_bool first_thread_used
= FALSE
;
270 GC_ASSERT(I_HOLD_LOCK());
271 if (!first_thread_used
) {
272 result
= &first_thread
;
273 first_thread_used
= TRUE
;
275 GC_ASSERT(!GC_win32_dll_threads
);
276 result
= (struct GC_Thread_Rep
*)
277 GC_INTERNAL_MALLOC(sizeof(struct GC_Thread_Rep
), NORMAL
);
279 /* result can be NULL -> segfault */
280 GC_ASSERT(result
-> flags
== 0);
283 if (result
== 0) return(0);
284 /* result -> id = id; Done by caller. */
285 result
-> next
= GC_threads
[hv
];
286 GC_threads
[hv
] = result
;
288 GC_ASSERT(result
-> flags
== 0 /* && result -> thread_blocked == 0 */);
293 extern LONG WINAPI
GC_write_fault_handler(struct _EXCEPTION_POINTERS
*exc_info
);
295 #if defined(GWW_VDB) && defined(MPROTECT_VDB)
296 extern GC_bool
GC_gww_dirty_init(void);
297 /* Defined in os_dep.c. Returns TRUE if GetWriteWatch is available. */
298 /* may be called repeatedly. */
301 GC_bool GC_in_thread_creation
= FALSE
; /* Protected by allocation lock. */
304 * This may be called from DllMain, and hence operates under unusual
305 * constraints. In particular, it must be lock-free if GC_win32_dll_threads
306 * is set. Always called from the thread being added.
307 * If GC_win32_dll_threads is not set, we already hold the allocation lock,
308 * except possibly during single-threaded start-up code.
310 static GC_thread
GC_register_my_thread_inner(struct GC_stack_base
*sb
,
315 /* The following should be a noop according to the win32 */
316 /* documentation. There is empirical evidence that it */
318 # if defined(MPROTECT_VDB)
319 # if defined(GWW_VDB)
320 if (GC_incremental
&& !GC_gww_dirty_init())
321 SetUnhandledExceptionFilter(GC_write_fault_handler
);
323 if (GC_incremental
) SetUnhandledExceptionFilter(GC_write_fault_handler
);
327 if (GC_win32_dll_threads
) {
329 /* It appears to be unsafe to acquire a lock here, since this */
330 /* code is apparently not preeemptible on some systems. */
331 /* (This is based on complaints, not on Microsoft's official */
332 /* documentation, which says this should perform "only simple */
333 /* initialization tasks".) */
334 /* Hence we make do with nonblocking synchronization. */
335 /* It has been claimed that DllMain is really only executed with */
336 /* a particular system lock held, and thus careful use of locking */
337 /* around code that doesn't call back into the system libraries */
338 /* might be OK. But this hasn't been tested across all win32 */
340 /* cast away volatile qualifier */
341 for (i
= 0; InterlockedExchange((IE_t
)&dll_thread_table
[i
].in_use
,1) != 0;
343 /* Compare-and-swap would make this cleaner, but that's not */
344 /* supported before Windows 98 and NT 4.0. In Windows 2000, */
345 /* InterlockedExchange is supposed to be replaced by */
346 /* InterlockedExchangePointer, but that's not really what I */
348 /* FIXME: We should eventually declare Win95 dead and use AO_ */
349 /* primitives here. */
350 if (i
== MAX_THREADS
- 1)
351 ABORT("too many threads");
353 /* Update GC_max_thread_index if necessary. The following is safe, */
354 /* and unlike CompareExchange-based solutions seems to work on all */
355 /* Windows95 and later platforms. */
356 /* Unfortunately, GC_max_thread_index may be temporarily out of */
357 /* bounds, so readers have to compensate. */
358 while (i
> GC_max_thread_index
) {
359 InterlockedIncrement((IE_t
)&GC_max_thread_index
);
361 if (GC_max_thread_index
>= MAX_THREADS
) {
362 /* We overshot due to simultaneous increments. */
363 /* Setting it to MAX_THREADS-1 is always safe. */
364 GC_max_thread_index
= MAX_THREADS
- 1;
366 me
= dll_thread_table
+ i
;
367 } else /* Not using DllMain */ {
368 GC_ASSERT(I_HOLD_LOCK());
369 GC_in_thread_creation
= TRUE
; /* OK to collect from unknown thread. */
370 me
= GC_new_thread(thread_id
);
371 GC_in_thread_creation
= FALSE
;
374 /* me can be NULL -> segfault */
375 me
-> pthread_id
= pthread_self();
378 if (!DuplicateHandle(GetCurrentProcess(),
381 (HANDLE
*)&(me
-> handle
),
384 DUPLICATE_SAME_ACCESS
)) {
385 DWORD last_error
= GetLastError();
386 GC_err_printf("Last error code: %d\n", last_error
);
387 ABORT("DuplicateHandle failed");
389 me
-> stack_base
= sb
-> mem_base
;
390 /* Up until this point, GC_push_all_stacks considers this thread */
392 /* Up until this point, this entry is viewed as reserved but invalid */
393 /* by GC_delete_thread. */
394 me
-> id
= thread_id
;
395 # if defined(THREAD_LOCAL_ALLOC)
396 GC_init_thread_local((GC_tlfs
)(&(me
->tlfs
)));
398 if (me
-> stack_base
== NULL
)
399 ABORT("Bad stack base in GC_register_my_thread_inner");
400 if (GC_win32_dll_threads
) {
401 if (GC_please_stop
) {
402 AO_store(&GC_attached_thread
, TRUE
);
403 AO_nop_full(); // Later updates must become visible after this.
405 /* We'd like to wait here, but can't, since waiting in DllMain */
406 /* provokes deadlocks. */
407 /* Thus we force marking to be restarted instead. */
409 GC_ASSERT(!GC_please_stop
);
410 /* Otherwise both we and the thread stopping code would be */
411 /* holding the allocation lock. */
413 return (GC_thread
)(me
);
417 * GC_max_thread_index may temporarily be larger than MAX_THREADS.
418 * To avoid subscript errors, we check on access.
423 LONG
GC_get_max_thread_index()
425 LONG my_max
= GC_max_thread_index
;
427 if (my_max
>= MAX_THREADS
) return MAX_THREADS
-1;
431 /* Return the GC_thread corresponding to a thread id. May be called */
432 /* without a lock, but should be called in contexts in which the */
433 /* requested thread cannot be asynchronously deleted, e.g. from the */
435 /* This version assumes that either GC_win32_dll_threads is set, or */
436 /* we hold the allocator lock. */
437 /* Also used (for assertion checking only) from thread_local_alloc.c. */
438 GC_thread
GC_lookup_thread_inner(DWORD thread_id
) {
439 if (GC_win32_dll_threads
) {
441 LONG my_max
= GC_get_max_thread_index();
444 (!AO_load_acquire(&(dll_thread_table
[i
].in_use
))
445 || dll_thread_table
[i
].id
!= thread_id
);
446 /* Must still be in_use, since nobody else can store our thread_id. */
451 return (GC_thread
)(dll_thread_table
+ i
);
454 word hv
= ((word
)thread_id
) % THREAD_TABLE_SZ
;
455 register GC_thread p
= GC_threads
[hv
];
457 GC_ASSERT(I_HOLD_LOCK());
458 while (p
!= 0 && p
-> id
!= thread_id
) p
= p
-> next
;
463 /* A version of the above that acquires the lock if necessary. Note */
464 /* that the identically named function for pthreads is different, and */
465 /* just assumes we hold the lock. */
466 /* Also used (for assertion checking only) from thread_local_alloc.c. */
467 static GC_thread
GC_lookup_thread(DWORD thread_id
)
469 if (GC_win32_dll_threads
) {
470 return GC_lookup_thread_inner(thread_id
);
474 result
= GC_lookup_thread_inner(thread_id
);
480 /* If a thread has been joined, but we have not yet */
481 /* been notified, then there may be more than one thread */
482 /* in the table with the same win32 id. */
483 /* This is OK, but we need a way to delete a specific one. */
484 /* Assumes we hold the allocation lock unless */
485 /* GC_win32_dll_threads is set. */
486 /* If GC_win32_dll_threads is set it should be called from the */
487 /* thread being deleted. */
488 void GC_delete_gc_thread(GC_vthread gc_id
)
490 if (GC_win32_dll_threads
) {
491 /* This is intended to be lock-free. */
492 /* It is either called synchronously from the thread being deleted, */
493 /* or by the joining thread. */
494 /* In this branch asynchronosu changes to *gc_id are possible. */
495 CloseHandle(gc_id
->handle
);
496 gc_id
-> stack_base
= 0;
499 gc_id
-> pthread_id
= 0;
500 # endif /* CYGWIN32 */
501 # ifdef GC_WIN32_PTHREADS
502 gc_id
-> pthread_id
.p
= NULL
;
503 # endif /* GC_WIN32_PTHREADS */
504 AO_store_release(&(gc_id
->in_use
), FALSE
);
506 /* Cast away volatile qualifier, since we have lock. */
507 GC_thread gc_nvid
= (GC_thread
)gc_id
;
508 DWORD id
= gc_nvid
-> id
;
509 word hv
= ((word
)id
) % THREAD_TABLE_SZ
;
510 register GC_thread p
= GC_threads
[hv
];
511 register GC_thread prev
= 0;
513 GC_ASSERT(I_HOLD_LOCK());
514 while (p
!= gc_nvid
) {
519 GC_threads
[hv
] = p
-> next
;
521 prev
-> next
= p
-> next
;
527 /* Delete a thread from GC_threads. We assume it is there. */
528 /* (The code intentionally traps if it wasn't.) */
529 /* Assumes we hold the allocation lock unless */
530 /* GC_win32_dll_threads is set. */
531 /* If GC_win32_dll_threads is set it should be called from the */
532 /* thread being deleted. */
533 void GC_delete_thread(DWORD id
)
535 if (GC_win32_dll_threads
) {
536 GC_thread t
= GC_lookup_thread_inner(id
);
539 WARN("Removing nonexistent thread %ld\n", (GC_word
)id
);
541 GC_delete_gc_thread(t
);
544 word hv
= ((word
)id
) % THREAD_TABLE_SZ
;
545 register GC_thread p
= GC_threads
[hv
];
546 register GC_thread prev
= 0;
548 GC_ASSERT(I_HOLD_LOCK());
549 while (p
-> id
!= id
) {
554 GC_threads
[hv
] = p
-> next
;
556 prev
-> next
= p
-> next
;
562 int GC_register_my_thread(struct GC_stack_base
*sb
) {
563 DWORD t
= GetCurrentThreadId();
565 if (0 == GC_lookup_thread(t
)) {
566 /* We lock here, since we want to wait for an ongoing GC. */
568 GC_register_my_thread_inner(sb
, t
);
576 int GC_unregister_my_thread(void)
578 DWORD t
= GetCurrentThreadId();
580 # if defined(THREAD_LOCAL_ALLOC)
583 GC_thread me
= GC_lookup_thread_inner(t
);
584 GC_destroy_thread_local(&(me
->tlfs
));
588 if (GC_win32_dll_threads
) {
589 /* Should we just ignore this? */
602 /* A quick-and-dirty cache of the mapping between pthread_t */
603 /* and win32 thread id. */
604 #define PTHREAD_MAP_SIZE 512
605 DWORD GC_pthread_map_cache
[PTHREAD_MAP_SIZE
];
606 #define HASH(pthread_id) ((NUMERIC_THREAD_ID(pthread_id) >> 5) % PTHREAD_MAP_SIZE)
607 /* It appears pthread_t is really a pointer type ... */
608 #define SET_PTHREAD_MAP_CACHE(pthread_id, win32_id) \
609 GC_pthread_map_cache[HASH(pthread_id)] = (win32_id);
610 #define GET_PTHREAD_MAP_CACHE(pthread_id) \
611 GC_pthread_map_cache[HASH(pthread_id)]
613 /* Return a GC_thread corresponding to a given pthread_t. */
614 /* Returns 0 if it's not there. */
615 /* We assume that this is only called for pthread ids that */
616 /* have not yet terminated or are still joinable, and */
617 /* cannot be concurrently terminated. */
618 /* Assumes we do NOT hold the allocation lock. */
619 static GC_thread
GC_lookup_pthread(pthread_t id
)
621 if (GC_win32_dll_threads
) {
623 LONG my_max
= GC_get_max_thread_index();
627 (!AO_load_acquire(&(dll_thread_table
[i
].in_use
))
628 || THREAD_EQUAL(dll_thread_table
[i
].pthread_id
, id
));
629 /* Must still be in_use, since nobody else can store our thread_id. */
631 if (i
> my_max
) return 0;
632 return (GC_thread
)(dll_thread_table
+ i
);
634 /* We first try the cache. If that fails, we use a very slow */
636 int hv_guess
= GET_PTHREAD_MAP_CACHE(id
) % THREAD_TABLE_SZ
;
641 for (p
= GC_threads
[hv_guess
]; 0 != p
; p
= p
-> next
) {
642 if (THREAD_EQUAL(p
-> pthread_id
, id
))
645 for (hv
= 0; hv
< THREAD_TABLE_SZ
; ++hv
) {
646 for (p
= GC_threads
[hv
]; 0 != p
; p
= p
-> next
) {
647 if (THREAD_EQUAL(p
-> pthread_id
, id
))
658 #endif /* GC_PTHREADS */
660 void GC_push_thread_structures(void)
662 GC_ASSERT(I_HOLD_LOCK());
663 if (GC_win32_dll_threads
) {
664 /* Unlike the other threads implementations, the thread table here */
665 /* contains no pointers to the collectable heap. Thus we have */
666 /* no private structures we need to preserve. */
668 { int i
; /* pthreads may keep a pointer in the thread exit value */
669 LONG my_max
= GC_get_max_thread_index();
671 for (i
= 0; i
<= my_max
; i
++)
672 if (dll_thread_table
[i
].in_use
)
673 GC_push_all((ptr_t
)&(dll_thread_table
[i
].status
),
674 (ptr_t
)(&(dll_thread_table
[i
].status
)+1));
678 GC_push_all((ptr_t
)(GC_threads
), (ptr_t
)(GC_threads
)+sizeof(GC_threads
));
680 # if defined(THREAD_LOCAL_ALLOC)
681 GC_push_all((ptr_t
)(&GC_thread_key
),
682 (ptr_t
)(&GC_thread_key
)+sizeof(&GC_thread_key
));
683 /* Just in case we ever use our own TLS implementation. */
687 /* Suspend the given thread, if it's still active. */
688 void GC_suspend(GC_thread t
)
691 /* SuspendThread will fail if thread is running kernel code */
692 while (SuspendThread(t
-> handle
) == (DWORD
)-1)
695 /* Apparently the Windows 95 GetOpenFileName call creates */
696 /* a thread that does not properly get cleaned up, and */
697 /* SuspendThread on its descriptor may provoke a crash. */
698 /* This reduces the probability of that event, though it still */
699 /* appears there's a race here. */
701 if (GetExitCodeThread(t
-> handle
, &exitCode
) &&
702 exitCode
!= STILL_ACTIVE
) {
703 t
-> stack_base
= 0; /* prevent stack from being pushed */
705 /* this breaks pthread_join on Cygwin, which is guaranteed to */
706 /* only see user pthreads */
707 AO_store(&(t
-> in_use
), FALSE
);
708 CloseHandle(t
-> handle
);
712 if (SuspendThread(t
-> handle
) == (DWORD
)-1)
713 ABORT("SuspendThread failed");
715 t
-> suspended
= TRUE
;
718 /* Defined in misc.c */
720 extern CRITICAL_SECTION GC_write_cs
;
723 void GC_stop_world(void)
725 DWORD thread_id
= GetCurrentThreadId();
728 if (!GC_thr_initialized
) ABORT("GC_stop_world() called before GC_thr_init()");
729 GC_ASSERT(I_HOLD_LOCK());
731 GC_please_stop
= TRUE
;
733 EnterCriticalSection(&GC_write_cs
);
735 if (GC_win32_dll_threads
) {
736 /* Any threads being created during this loop will end up setting */
737 /* GC_attached_thread when they start. This will force marking to */
739 /* This is not ideal, but hopefully correct. */
740 GC_attached_thread
= FALSE
;
741 for (i
= 0; i
<= GC_get_max_thread_index(); i
++) {
742 GC_vthread t
= dll_thread_table
+ i
;
743 if (t
-> stack_base
!= 0
744 && t
-> id
!= thread_id
) {
745 GC_suspend((GC_thread
)t
);
752 for (i
= 0; i
< THREAD_TABLE_SZ
; i
++) {
753 for (t
= GC_threads
[i
]; t
!= 0; t
= t
-> next
) {
754 if (t
-> stack_base
!= 0
755 && !KNOWN_FINISHED(t
)
756 && t
-> id
!= thread_id
) {
763 LeaveCriticalSection(&GC_write_cs
);
767 void GC_start_world(void)
769 DWORD thread_id
= GetCurrentThreadId();
771 LONG my_max
= GC_get_max_thread_index();
773 GC_ASSERT(I_HOLD_LOCK());
774 if (GC_win32_dll_threads
) {
775 for (i
= 0; i
<= my_max
; i
++) {
776 GC_thread t
= (GC_thread
)(dll_thread_table
+ i
);
777 if (t
-> stack_base
!= 0 && t
-> suspended
778 && t
-> id
!= thread_id
) {
779 if (ResumeThread(t
-> handle
) == (DWORD
)-1)
780 ABORT("ResumeThread failed");
781 t
-> suspended
= FALSE
;
788 for (i
= 0; i
< THREAD_TABLE_SZ
; i
++) {
789 for (t
= GC_threads
[i
]; t
!= 0; t
= t
-> next
) {
790 if (t
-> stack_base
!= 0 && t
-> suspended
791 && t
-> id
!= thread_id
) {
792 if (ResumeThread(t
-> handle
) == (DWORD
)-1)
793 ABORT("ResumeThread failed");
794 t
-> suspended
= FALSE
;
799 GC_please_stop
= FALSE
;
803 /* The VirtualQuery calls below won't work properly on WinCE, but */
804 /* since each stack is restricted to an aligned 64K region of */
805 /* virtual memory we can just take the next lowest multiple of 64K. */
806 # define GC_get_stack_min(s) \
807 ((ptr_t)(((DWORD)(s) - 1) & 0xFFFF0000))
809 static ptr_t
GC_get_stack_min(ptr_t s
)
812 MEMORY_BASIC_INFORMATION info
;
813 VirtualQuery(s
, &info
, sizeof(info
));
815 bottom
= info
.BaseAddress
;
816 VirtualQuery(bottom
- 1, &info
, sizeof(info
));
817 } while ((info
.Protect
& PAGE_READWRITE
)
818 && !(info
.Protect
& PAGE_GUARD
));
823 void GC_push_stack_for(GC_thread thread
)
827 DWORD me
= GetCurrentThreadId();
829 if (thread
-> stack_base
) {
830 if (thread
-> id
== me
) {
834 context
.ContextFlags
= CONTEXT_INTEGER
|CONTEXT_CONTROL
;
835 if (!GetThreadContext(thread
-> handle
, &context
))
836 ABORT("GetThreadContext failed");
838 /* Push all registers that might point into the heap. Frame */
839 /* pointer registers are included in case client code was */
840 /* compiled with the 'omit frame pointer' optimisation. */
841 # define PUSH1(reg) GC_push_one((word)context.reg)
842 # define PUSH2(r1,r2) PUSH1(r1), PUSH1(r2)
843 # define PUSH4(r1,r2,r3,r4) PUSH2(r1,r2), PUSH2(r3,r4)
845 PUSH4(Edi
,Esi
,Ebx
,Edx
), PUSH2(Ecx
,Eax
), PUSH1(Ebp
);
846 sp
= (ptr_t
)context
.Esp
;
847 # elif defined(X86_64)
848 PUSH4(Rax
,Rcx
,Rdx
,Rbx
); PUSH2(Rbp
, Rsi
); PUSH1(Rdi
);
849 PUSH4(R8
, R9
, R10
, R11
); PUSH4(R12
, R13
, R14
, R15
);
850 sp
= (ptr_t
)context
.Rsp
;
851 # elif defined(ARM32)
852 PUSH4(R0
,R1
,R2
,R3
),PUSH4(R4
,R5
,R6
,R7
),PUSH4(R8
,R9
,R10
,R11
),PUSH1(R12
);
853 sp
= (ptr_t
)context
.Sp
;
855 PUSH4(R0
,R1
,R2
,R3
), PUSH4(R4
,R5
,R6
,R7
), PUSH4(R8
,R9
,R10
,R11
);
856 PUSH2(R12
,R13
), PUSH1(R14
);
857 sp
= (ptr_t
)context
.R15
;
859 PUSH4(IntAt
,IntV0
,IntV1
,IntA0
), PUSH4(IntA1
,IntA2
,IntA3
,IntT0
);
860 PUSH4(IntT1
,IntT2
,IntT3
,IntT4
), PUSH4(IntT5
,IntT6
,IntT7
,IntS0
);
861 PUSH4(IntS1
,IntS2
,IntS3
,IntS4
), PUSH4(IntS5
,IntS6
,IntS7
,IntT8
);
862 PUSH4(IntT9
,IntK0
,IntK1
,IntS8
);
863 sp
= (ptr_t
)context
.IntSp
;
865 PUSH4(Gpr0
, Gpr3
, Gpr4
, Gpr5
), PUSH4(Gpr6
, Gpr7
, Gpr8
, Gpr9
);
866 PUSH4(Gpr10
,Gpr11
,Gpr12
,Gpr14
), PUSH4(Gpr15
,Gpr16
,Gpr17
,Gpr18
);
867 PUSH4(Gpr19
,Gpr20
,Gpr21
,Gpr22
), PUSH4(Gpr23
,Gpr24
,Gpr25
,Gpr26
);
868 PUSH4(Gpr27
,Gpr28
,Gpr29
,Gpr30
), PUSH1(Gpr31
);
869 sp
= (ptr_t
)context
.Gpr1
;
870 # elif defined(ALPHA)
871 PUSH4(IntV0
,IntT0
,IntT1
,IntT2
), PUSH4(IntT3
,IntT4
,IntT5
,IntT6
);
872 PUSH4(IntT7
,IntS0
,IntS1
,IntS2
), PUSH4(IntS3
,IntS4
,IntS5
,IntFp
);
873 PUSH4(IntA0
,IntA1
,IntA2
,IntA3
), PUSH4(IntA4
,IntA5
,IntT8
,IntT9
);
874 PUSH4(IntT10
,IntT11
,IntT12
,IntAt
);
875 sp
= (ptr_t
)context
.IntSp
;
877 # error "architecture is not supported"
879 } /* ! current thread */
881 stack_min
= GC_get_stack_min(thread
->stack_base
);
883 if (sp
>= stack_min
&& sp
< thread
->stack_base
) {
884 # if DEBUG_WIN32_PTHREADS || DEBUG_WIN32_THREADS \
885 || DEBUG_CYGWIN_THREADS
886 GC_printf("Pushing thread from %p to %p for 0x%x from 0x%x\n",
887 sp
, thread
-> stack_base
, thread
-> id
, me
);
889 GC_push_all_stack(sp
, thread
->stack_base
);
891 WARN("Thread stack pointer 0x%lx out of range, pushing everything\n",
892 (unsigned long)(size_t)sp
);
893 GC_push_all_stack(stack_min
, thread
->stack_base
);
895 } /* thread looks live */
898 void GC_push_all_stacks(void)
900 DWORD me
= GetCurrentThreadId();
901 GC_bool found_me
= FALSE
;
904 if (GC_win32_dll_threads
) {
906 LONG my_max
= GC_get_max_thread_index();
908 for (i
= 0; i
<= my_max
; i
++) {
909 GC_thread t
= (GC_thread
)(dll_thread_table
+ i
);
912 GC_push_stack_for(t
);
913 if (t
-> id
== me
) found_me
= TRUE
;
920 for (i
= 0; i
< THREAD_TABLE_SZ
; i
++) {
921 for (t
= GC_threads
[i
]; t
!= 0; t
= t
-> next
) {
923 if (!KNOWN_FINISHED(t
)) GC_push_stack_for(t
);
924 if (t
-> id
== me
) found_me
= TRUE
;
928 if (GC_print_stats
== VERBOSE
) {
929 GC_log_printf("Pushed %d thread stacks ", nthreads
);
930 if (GC_win32_dll_threads
) {
931 GC_log_printf("based on DllMain thread tracking\n");
936 if (!found_me
&& !GC_in_thread_creation
)
937 ABORT("Collecting from unknown thread.");
940 void GC_get_next_stack(char *start
, char **lo
, char **hi
)
943 # define ADDR_LIMIT (char *)(-1L)
944 char * current_min
= ADDR_LIMIT
;
946 if (GC_win32_dll_threads
) {
947 LONG my_max
= GC_get_max_thread_index();
949 for (i
= 0; i
<= my_max
; i
++) {
950 ptr_t s
= (ptr_t
)(dll_thread_table
[i
].stack_base
);
952 if (0 != s
&& s
> start
&& s
< current_min
) {
957 for (i
= 0; i
< THREAD_TABLE_SZ
; i
++) {
960 for (t
= GC_threads
[i
]; t
!= 0; t
= t
-> next
) {
961 ptr_t s
= (ptr_t
)(t
-> stack_base
);
963 if (0 != s
&& s
> start
&& s
< current_min
) {
970 if (current_min
== ADDR_LIMIT
) {
974 *lo
= GC_get_stack_min(current_min
);
975 if (*lo
< start
) *lo
= start
;
980 /* We have no DllMain to take care of new threads. Thus we */
981 /* must properly intercept thread creation. */
984 LPTHREAD_START_ROUTINE start
;
988 static DWORD WINAPI
thread_start(LPVOID arg
);
990 void * GC_win32_start_inner(struct GC_stack_base
*sb
, LPVOID arg
)
993 thread_args
*args
= (thread_args
*)arg
;
995 # if DEBUG_WIN32_THREADS
996 GC_printf("thread 0x%x starting...\n", GetCurrentThreadId());
999 GC_register_my_thread(sb
); /* This waits for an in-progress GC. */
1001 /* Clear the thread entry even if we exit with an exception. */
1002 /* This is probably pointless, since an uncaught exception is */
1003 /* supposed to result in the process being killed. */
1006 #endif /* __GNUC__ */
1007 ret
= (void *)(size_t)args
->start (args
->param
);
1010 #endif /* __GNUC__ */
1011 GC_unregister_my_thread();
1015 #endif /* __GNUC__ */
1017 # if DEBUG_WIN32_THREADS
1018 GC_printf("thread 0x%x returned from start routine.\n",
1019 GetCurrentThreadId());
1024 DWORD WINAPI
GC_win32_start(LPVOID arg
)
1026 return (DWORD
)(size_t)GC_call_with_stack_base(GC_win32_start_inner
, arg
);
1029 GC_API HANDLE WINAPI
GC_CreateThread(
1030 LPSECURITY_ATTRIBUTES lpThreadAttributes
,
1031 DWORD dwStackSize
, LPTHREAD_START_ROUTINE lpStartAddress
,
1032 LPVOID lpParameter
, DWORD dwCreationFlags
, LPDWORD lpThreadId
)
1034 HANDLE thread_h
= NULL
;
1038 if (!parallel_initialized
) GC_init_parallel();
1039 /* make sure GC is initialized (i.e. main thread is attached,
1042 # if DEBUG_WIN32_THREADS
1043 GC_printf("About to create a thread from 0x%x\n", GetCurrentThreadId());
1045 if (GC_win32_dll_threads
) {
1046 return CreateThread(lpThreadAttributes
, dwStackSize
, lpStartAddress
,
1047 lpParameter
, dwCreationFlags
, lpThreadId
);
1049 args
= GC_malloc_uncollectable(sizeof(thread_args
));
1050 /* Handed off to and deallocated by child thread. */
1052 SetLastError(ERROR_NOT_ENOUGH_MEMORY
);
1056 /* set up thread arguments */
1057 args
-> start
= lpStartAddress
;
1058 args
-> param
= lpParameter
;
1060 GC_need_to_lock
= TRUE
;
1061 thread_h
= CreateThread(lpThreadAttributes
,
1062 dwStackSize
, GC_win32_start
,
1063 args
, dwCreationFlags
,
1065 if( thread_h
== 0 ) GC_free( args
);
1070 void WINAPI
GC_ExitThread(DWORD dwExitCode
)
1072 GC_unregister_my_thread();
1073 ExitThread(dwExitCode
);
1076 uintptr_t GC_beginthreadex(
1077 void *security
, unsigned stack_size
,
1078 unsigned ( __stdcall
*start_address
)( void * ),
1079 void *arglist
, unsigned initflag
, unsigned *thrdaddr
)
1081 uintptr_t thread_h
= -1L;
1085 if (!parallel_initialized
) GC_init_parallel();
1086 /* make sure GC is initialized (i.e. main thread is attached,
1088 # if DEBUG_WIN32_THREADS
1089 GC_printf("About to create a thread from 0x%x\n", GetCurrentThreadId());
1092 if (GC_win32_dll_threads
) {
1093 return _beginthreadex(security
, stack_size
, start_address
,
1094 arglist
, initflag
, thrdaddr
);
1096 args
= GC_malloc_uncollectable(sizeof(thread_args
));
1097 /* Handed off to and deallocated by child thread. */
1099 SetLastError(ERROR_NOT_ENOUGH_MEMORY
);
1100 return (uintptr_t)(-1);
1103 /* set up thread arguments */
1104 args
-> start
= (LPTHREAD_START_ROUTINE
)start_address
;
1105 args
-> param
= arglist
;
1107 GC_need_to_lock
= TRUE
;
1108 thread_h
= _beginthreadex(security
, stack_size
,
1109 (unsigned (__stdcall
*) (void *))GC_win32_start
,
1110 args
, initflag
, thrdaddr
);
1111 if( thread_h
== 0 ) GC_free( args
);
1116 void GC_endthreadex(unsigned retval
)
1118 GC_unregister_my_thread();
1119 _endthreadex(retval
);
1122 #endif /* !GC_PTHREADS */
1127 HINSTANCE hInstance
;
1128 HINSTANCE hPrevInstance
;
1133 DWORD WINAPI
main_thread_start(LPVOID arg
);
1135 int WINAPI
WinMain(HINSTANCE hInstance
, HINSTANCE hPrevInstance
,
1136 LPWSTR lpCmdLine
, int nShowCmd
)
1138 DWORD exit_code
= 1;
1140 main_thread_args args
= {
1141 hInstance
, hPrevInstance
, lpCmdLine
, nShowCmd
1146 /* initialize everything */
1149 /* start the main thread */
1150 thread_h
= GC_CreateThread(
1151 NULL
, 0, main_thread_start
, &args
, 0, &thread_id
);
1153 if (thread_h
!= NULL
)
1155 WaitForSingleObject (thread_h
, INFINITE
);
1156 GetExitCodeThread (thread_h
, &exit_code
);
1157 CloseHandle (thread_h
);
1161 DeleteCriticalSection(&GC_allocate_ml
);
1163 return (int) exit_code
;
1166 DWORD WINAPI
main_thread_start(LPVOID arg
)
1168 main_thread_args
* args
= (main_thread_args
*) arg
;
1170 return (DWORD
) GC_WinMain (args
->hInstance
, args
->hPrevInstance
,
1171 args
->lpCmdLine
, args
->nShowCmd
);
1174 # else /* !MSWINCE */
1176 /* Called by GC_init() - we hold the allocation lock. */
1177 void GC_thr_init(void) {
1178 struct GC_stack_base sb
;
1181 GC_ASSERT(I_HOLD_LOCK());
1182 if (GC_thr_initialized
) return;
1183 GC_main_thread
= GetCurrentThreadId();
1184 GC_thr_initialized
= TRUE
;
1186 /* Add the initial thread, so we can stop it. */
1187 sb_result
= GC_get_stack_base(&sb
);
1188 GC_ASSERT(sb_result
== GC_SUCCESS
);
1189 GC_register_my_thread(&sb
);
1195 void *(*start_routine
)(void *);
1200 int GC_pthread_join(pthread_t pthread_id
, void **retval
) {
1205 # if DEBUG_CYGWIN_THREADS
1206 GC_printf("thread 0x%x(0x%x) is joining thread 0x%x.\n",
1207 (int)pthread_self(), GetCurrentThreadId(), (int)pthread_id
);
1209 # if DEBUG_WIN32_PTHREADS
1210 GC_printf("thread 0x%x(0x%x) is joining thread 0x%x.\n",
1211 (int)(pthread_self()).p
, GetCurrentThreadId(), pthread_id
.p
);
1214 if (!parallel_initialized
) GC_init_parallel();
1215 /* Thread being joined might not have registered itself yet. */
1216 /* After the join,thread id may have been recycled. */
1217 /* FIXME: It would be better if this worked more like */
1218 /* pthread_support.c. */
1220 #ifndef GC_WIN32_PTHREADS
1221 while ((joinee
= GC_lookup_pthread(pthread_id
)) == 0) Sleep(10);
1224 result
= pthread_join(pthread_id
, retval
);
1226 #ifdef GC_WIN32_PTHREADS
1227 /* win32_pthreads id are unique */
1228 joinee
= GC_lookup_pthread(pthread_id
);
1231 if (!GC_win32_dll_threads
) {
1233 GC_delete_gc_thread(joinee
);
1235 } /* otherwise dllmain handles it. */
1237 # if DEBUG_CYGWIN_THREADS
1238 GC_printf("thread 0x%x(0x%x) completed join with thread 0x%x.\n",
1239 (int)pthread_self(), GetCurrentThreadId(), (int)pthread_id
);
1241 # if DEBUG_WIN32_PTHREADS
1242 GC_printf("thread 0x%x(0x%x) completed join with thread 0x%x.\n",
1243 (int)(pthread_self()).p
, GetCurrentThreadId(), pthread_id
.p
);
1249 /* Cygwin-pthreads calls CreateThread internally, but it's not
1250 * easily interceptible by us..
1251 * so intercept pthread_create instead
1254 GC_pthread_create(pthread_t
*new_thread
,
1255 const pthread_attr_t
*attr
,
1256 void *(*start_routine
)(void *), void *arg
) {
1258 struct start_info
* si
;
1260 if (!parallel_initialized
) GC_init_parallel();
1261 /* make sure GC is initialized (i.e. main thread is attached) */
1262 if (GC_win32_dll_threads
) {
1263 return pthread_create(new_thread
, attr
, start_routine
, arg
);
1266 /* This is otherwise saved only in an area mmapped by the thread */
1267 /* library, which isn't visible to the collector. */
1268 si
= GC_malloc_uncollectable(sizeof(struct start_info
));
1269 if (0 == si
) return(EAGAIN
);
1271 si
-> start_routine
= start_routine
;
1274 pthread_attr_getdetachstate(attr
, &si
->detached
)
1275 == PTHREAD_CREATE_DETACHED
) {
1276 si
->detached
= TRUE
;
1279 # if DEBUG_CYGWIN_THREADS
1280 GC_printf("About to create a thread from 0x%x(0x%x)\n",
1281 (int)pthread_self(), GetCurrentThreadId
);
1283 # if DEBUG_WIN32_PTHREADS
1284 GC_printf("About to create a thread from 0x%x(0x%x)\n",
1285 (int)(pthread_self()).p
, GetCurrentThreadId());
1287 GC_need_to_lock
= TRUE
;
1288 result
= pthread_create(new_thread
, attr
, GC_pthread_start
, si
);
1290 if (result
) { /* failure */
1297 void * GC_pthread_start_inner(struct GC_stack_base
*sb
, void * arg
)
1299 struct start_info
* si
= arg
;
1301 void *(*start
)(void *);
1303 DWORD thread_id
= GetCurrentThreadId();
1304 pthread_t pthread_id
= pthread_self();
1309 # if DEBUG_CYGWIN_THREADS
1310 GC_printf("thread 0x%x(0x%x) starting...\n",(int)pthread_id
,
1313 # if DEBUG_WIN32_PTHREADS
1314 GC_printf("thread 0x%x(0x%x) starting...\n",(int) pthread_id
.p
,
1318 GC_ASSERT(!GC_win32_dll_threads
);
1319 /* If a GC occurs before the thread is registered, that GC will */
1320 /* ignore this thread. That's fine, since it will block trying to */
1321 /* acquire the allocation lock, and won't yet hold interesting */
1324 /* We register the thread here instead of in the parent, so that */
1325 /* we don't need to hold the allocation lock during pthread_create. */
1326 me
= GC_register_my_thread_inner(sb
, thread_id
);
1327 SET_PTHREAD_MAP_CACHE(pthread_id
, thread_id
);
1330 start
= si
-> start_routine
;
1331 start_arg
= si
-> arg
;
1332 if (si
-> detached
) me
-> flags
|= DETACHED
;
1333 me
-> pthread_id
= pthread_id
;
1335 GC_free(si
); /* was allocated uncollectable */
1337 pthread_cleanup_push(GC_thread_exit_proc
, (void *)me
);
1338 result
= (*start
)(start_arg
);
1339 me
-> status
= result
;
1340 pthread_cleanup_pop(1);
1342 # if DEBUG_CYGWIN_THREADS
1343 GC_printf("thread 0x%x(0x%x) returned from start routine.\n",
1344 (int)pthread_self(),GetCurrentThreadId());
1346 # if DEBUG_WIN32_PTHREADS
1347 GC_printf("thread 0x%x(0x%x) returned from start routine.\n",
1348 (int)(pthread_self()).p
, GetCurrentThreadId());
1354 void * GC_pthread_start(void * arg
)
1356 return GC_call_with_stack_base(GC_pthread_start_inner
, arg
);
1359 void GC_thread_exit_proc(void *arg
)
1361 GC_thread me
= (GC_thread
)arg
;
1364 GC_ASSERT(!GC_win32_dll_threads
);
1365 # if DEBUG_CYGWIN_THREADS
1366 GC_printf("thread 0x%x(0x%x) called pthread_exit().\n",
1367 (int)pthread_self(),GetCurrentThreadId());
1369 # if DEBUG_WIN32_PTHREADS
1370 GC_printf("thread 0x%x(0x%x) called pthread_exit().\n",
1371 (int)(pthread_self()).p
,GetCurrentThreadId());
1375 # if defined(THREAD_LOCAL_ALLOC)
1376 GC_destroy_thread_local(&(me
->tlfs
));
1378 if (me
-> flags
& DETACHED
) {
1379 GC_delete_thread(GetCurrentThreadId());
1381 /* deallocate it as part of join */
1382 me
-> flags
|= FINISHED
;
1387 #ifndef GC_WIN32_PTHREADS
1388 /* win32 pthread does not support sigmask */
1389 /* nothing required here... */
1390 int GC_pthread_sigmask(int how
, const sigset_t
*set
, sigset_t
*oset
) {
1391 if (!parallel_initialized
) GC_init_parallel();
1392 return pthread_sigmask(how
, set
, oset
);
1396 int GC_pthread_detach(pthread_t thread
)
1399 GC_thread thread_gc_id
;
1401 if (!parallel_initialized
) GC_init_parallel();
1403 thread_gc_id
= GC_lookup_pthread(thread
);
1405 result
= pthread_detach(thread
);
1408 thread_gc_id
-> flags
|= DETACHED
;
1409 /* Here the pthread thread id may have been recycled. */
1410 if (thread_gc_id
-> flags
& FINISHED
) {
1411 GC_delete_gc_thread(thread_gc_id
);
1418 #else /* !GC_PTHREADS */
1421 * We avoid acquiring locks here, since this doesn't seem to be preemptable.
1422 * This may run with an uninitialized collector, in which case we don't do much.
1423 * This implies that no threads other than the main one should be created
1424 * with an uninitialized collector. (The alternative of initializing
1425 * the collector here seems dangerous, since DllMain is limited in what it
1429 GC_API BOOL WINAPI
DllMain(HINSTANCE inst
, ULONG reason
, LPVOID reserved
)
1431 struct GC_stack_base sb
;
1434 static int entry_count
= 0;
1436 if (parallel_initialized
&& !GC_win32_dll_threads
) return TRUE
;
1439 case DLL_THREAD_ATTACH
:
1440 GC_ASSERT(entry_count
== 0 || parallel_initialized
);
1441 ++entry_count
; /* and fall through: */
1442 case DLL_PROCESS_ATTACH
:
1443 /* This may run with the collector uninitialized. */
1444 thread_id
= GetCurrentThreadId();
1445 if (parallel_initialized
&& GC_main_thread
!= thread_id
) {
1446 /* Don't lock here. */
1447 sb_result
= GC_get_stack_base(&sb
);
1448 GC_ASSERT(sb_result
== GC_SUCCESS
);
1449 # ifdef THREAD_LOCAL_ALLOC
1450 ABORT("Cannot initialize thread local cache from DllMain");
1452 GC_register_my_thread_inner(&sb
, thread_id
);
1453 } /* o.w. we already did it during GC_thr_init(), called by GC_init() */
1456 case DLL_THREAD_DETACH
:
1457 /* We are hopefully running in the context of the exiting thread. */
1458 GC_ASSERT(parallel_initialized
);
1459 if (!GC_win32_dll_threads
) return TRUE
;
1460 GC_delete_thread(GetCurrentThreadId());
1463 case DLL_PROCESS_DETACH
:
1467 if (!GC_win32_dll_threads
) return TRUE
;
1468 for (i
= 0; i
<= GC_get_max_thread_index(); ++i
)
1470 if (AO_load(&(dll_thread_table
[i
].in_use
)))
1471 GC_delete_gc_thread(dll_thread_table
+ i
);
1475 DeleteCriticalSection(&GC_allocate_ml
);
1483 #endif /* !GC_PTHREADS */
1485 # endif /* !MSWINCE */
1487 /* Perform all initializations, including those that */
1488 /* may require allocation. */
1489 /* Called without allocation lock. */
1490 /* Must be called before a second thread is created. */
1491 void GC_init_parallel(void)
1493 if (parallel_initialized
) return;
1494 parallel_initialized
= TRUE
;
1495 /* GC_init() calls us back, so set flag first. */
1497 if (!GC_is_initialized
) GC_init();
1498 if (GC_win32_dll_threads
) {
1499 GC_need_to_lock
= TRUE
;
1500 /* Cannot intercept thread creation. Hence we don't know if other */
1501 /* threads exist. However, client is not allowed to create other */
1502 /* threads before collector initialization. Thus it's OK not to */
1503 /* lock before this. */
1505 /* Initialize thread local free lists if used. */
1506 # if defined(THREAD_LOCAL_ALLOC)
1508 GC_init_thread_local(&(GC_lookup_thread(GetCurrentThreadId())->tlfs
));
1513 #if defined(USE_PTHREAD_LOCKS)
1514 /* Support for pthread locking code. */
1515 /* Pthread_mutex_try_lock may not win here, */
1516 /* due to builtinsupport for spinning first? */
1518 volatile GC_bool GC_collecting
= 0;
1519 /* A hint that we're in the collector and */
1520 /* holding the allocation lock for an */
1521 /* extended period. */
1525 pthread_mutex_lock(&GC_allocate_ml
);
1527 #endif /* USE_PTHREAD ... */
1529 # if defined(THREAD_LOCAL_ALLOC)
1531 /* Add thread-local allocation support. Microsoft uses __declspec(thread) */
1533 /* We must explicitly mark ptrfree and gcj free lists, since the free */
1534 /* list links wouldn't otherwise be found. We also set them in the */
1535 /* normal free lists, since that involves touching less memory than if */
1536 /* we scanned them normally. */
1537 void GC_mark_thread_local_free_lists(void)
1542 for (i
= 0; i
< THREAD_TABLE_SZ
; ++i
) {
1543 for (p
= GC_threads
[i
]; 0 != p
; p
= p
-> next
) {
1544 GC_mark_thread_local_fls_for(&(p
->tlfs
));
1549 #if defined(GC_ASSERTIONS)
1550 /* Check that all thread-local free-lists are completely marked. */
1551 /* also check that thread-specific-data structures are marked. */
1552 void GC_check_tls(void) {
1556 for (i
= 0; i
< THREAD_TABLE_SZ
; ++i
) {
1557 for (p
= GC_threads
[i
]; 0 != p
; p
= p
-> next
) {
1558 GC_check_tls_for(&(p
->tlfs
));
1561 # if defined(USE_CUSTOM_SPECIFIC)
1562 if (GC_thread_key
!= 0)
1563 GC_check_tsd_marks(GC_thread_key
);
1566 #endif /* GC_ASSERTIONS */
1568 #endif /* THREAD_LOCAL_ALLOC ... */
1570 #endif /* GC_WIN32_THREADS */