[e90b2f]: src / gc-unstable / darwin_stop_world.c Maximize Restore History

Download this file

darwin_stop_world.c    668 lines (593 with data), 22.3 kB

  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
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
/*
* Copyright (c) 1994 by Xerox Corporation. All rights reserved.
* Copyright (c) 1996 by Silicon Graphics. All rights reserved.
* Copyright (c) 1998 by Fergus Henderson. All rights reserved.
* Copyright (c) 2000-2010 by Hewlett-Packard Development Company.
* All rights reserved.
*
* THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
* OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
*
* Permission is hereby granted to use or copy this program
* for any purpose, provided the above notices are retained on all copies.
* Permission to modify the code and to distribute modified code is granted,
* provided the above notices are retained, and a notice that the code was
* modified is included with the above copyright notice.
*/
#include "private/pthread_support.h"
/* This probably needs more porting work to ppc64. */
#if defined(GC_DARWIN_THREADS)
/* From "Inside Mac OS X - Mach-O Runtime Architecture" published by Apple
Page 49:
"The space beneath the stack pointer, where a new stack frame would normally
be allocated, is called the red zone. This area as shown in Figure 3-2 may
be used for any purpose as long as a new stack frame does not need to be
added to the stack."
Page 50: "If a leaf procedure's red zone usage would exceed 224 bytes, then
it must set up a stack frame just like routines that call other routines."
*/
#ifdef POWERPC
# if CPP_WORDSZ == 32
# define PPC_RED_ZONE_SIZE 224
# elif CPP_WORDSZ == 64
# define PPC_RED_ZONE_SIZE 320
# endif
#endif
#ifndef DARWIN_DONT_PARSE_STACK
typedef struct StackFrame {
unsigned long savedSP;
unsigned long savedCR;
unsigned long savedLR;
unsigned long reserved[2];
unsigned long savedRTOC;
} StackFrame;
GC_INNER ptr_t GC_FindTopOfStack(unsigned long stack_start)
{
StackFrame *frame;
if (stack_start == 0) {
# ifdef POWERPC
# if CPP_WORDSZ == 32
__asm__ __volatile__ ("lwz %0,0(r1)" : "=r" (frame));
# else
__asm__ __volatile__ ("ld %0,0(r1)" : "=r" (frame));
# endif
# endif
} else {
frame = (StackFrame *)stack_start;
}
# ifdef DEBUG_THREADS
/* GC_printf("FindTopOfStack start at sp = %p\n", frame); */
# endif
while (frame->savedSP != 0) {
/* if there are no more stack frames, stop */
frame = (StackFrame*)frame->savedSP;
/* we do these next two checks after going to the next frame
because the LR for the first stack frame in the loop
is not set up on purpose, so we shouldn't check it. */
if ((frame->savedLR & ~0x3) == 0 || (frame->savedLR & ~0x3) == ~0x3)
break; /* if the next LR is bogus, stop */
}
# ifdef DEBUG_THREADS
/* GC_printf("FindTopOfStack finish at sp = %p\n", frame); */
# endif
return (ptr_t)frame;
}
#endif /* !DARWIN_DONT_PARSE_STACK */
/* GC_query_task_threads controls whether to obtain the list of */
/* the threads from the kernel or to use GC_threads table. */
#ifdef GC_NO_THREADS_DISCOVERY
# define GC_query_task_threads FALSE
#elif defined(GC_DISCOVER_TASK_THREADS)
# define GC_query_task_threads TRUE
#else
STATIC GC_bool GC_query_task_threads = FALSE;
#endif /* !GC_NO_THREADS_DISCOVERY */
/* Use implicit threads registration (all task threads excluding the GC */
/* special ones are stoped and scanned). Should be called before */
/* GC_INIT() (or, at least, before going multi-threaded). Deprecated. */
GC_API void GC_CALL GC_use_threads_discovery(void)
{
# if defined(GC_NO_THREADS_DISCOVERY) || defined(DARWIN_DONT_PARSE_STACK)
ABORT("Darwin task-threads-based stop and push unsupported");
# else
GC_ASSERT(!GC_need_to_lock);
# ifndef GC_DISCOVER_TASK_THREADS
GC_query_task_threads = TRUE;
# endif
GC_init_parallel(); /* just to be consistent with Win32 one */
# endif
}
/* Evaluates the stack range for a given thread. Returns the lower */
/* bound and sets *phi to the upper one. */
STATIC ptr_t GC_stack_range_for(ptr_t *phi, thread_act_t thread, GC_thread p,
GC_bool thread_blocked, mach_port_t my_thread)
{
ptr_t lo;
if (thread == my_thread) {
GC_ASSERT(!thread_blocked);
lo = GC_approx_sp();
# ifndef DARWIN_DONT_PARSE_STACK
*phi = GC_FindTopOfStack(0);
# endif
} else if (thread_blocked) {
lo = p->stop_info.stack_ptr;
# ifndef DARWIN_DONT_PARSE_STACK
*phi = p->topOfStack;
# endif
} else {
/* MACHINE_THREAD_STATE_COUNT does not seem to be defined */
/* everywhere. Hence we use our own version. Alternatively, */
/* we could use THREAD_STATE_MAX (but seems to be not optimal). */
kern_return_t kern_result;
mach_msg_type_number_t thread_state_count = GC_MACH_THREAD_STATE_COUNT;
GC_THREAD_STATE_T state;
/* Get the thread state (registers, etc) */
kern_result = thread_get_state(thread, GC_MACH_THREAD_STATE,
(natural_t *)&state,
&thread_state_count);
# ifdef DEBUG_THREADS
GC_log_printf("thread_get_state returns value = %d\n", kern_result);
# endif
if (kern_result != KERN_SUCCESS)
ABORT("thread_get_state failed");
# if defined(I386)
lo = (void *)state.THREAD_FLD(esp);
# ifndef DARWIN_DONT_PARSE_STACK
*phi = GC_FindTopOfStack(state.THREAD_FLD(esp));
# endif
GC_push_one(state.THREAD_FLD(eax));
GC_push_one(state.THREAD_FLD(ebx));
GC_push_one(state.THREAD_FLD(ecx));
GC_push_one(state.THREAD_FLD(edx));
GC_push_one(state.THREAD_FLD(edi));
GC_push_one(state.THREAD_FLD(esi));
GC_push_one(state.THREAD_FLD(ebp));
# elif defined(X86_64)
lo = (void *)state.THREAD_FLD(rsp);
# ifndef DARWIN_DONT_PARSE_STACK
*phi = GC_FindTopOfStack(state.THREAD_FLD(rsp));
# endif
GC_push_one(state.THREAD_FLD(rax));
GC_push_one(state.THREAD_FLD(rbx));
GC_push_one(state.THREAD_FLD(rcx));
GC_push_one(state.THREAD_FLD(rdx));
GC_push_one(state.THREAD_FLD(rdi));
GC_push_one(state.THREAD_FLD(rsi));
GC_push_one(state.THREAD_FLD(rbp));
/* GC_push_one(state.THREAD_FLD(rsp)); */
GC_push_one(state.THREAD_FLD(r8));
GC_push_one(state.THREAD_FLD(r9));
GC_push_one(state.THREAD_FLD(r10));
GC_push_one(state.THREAD_FLD(r11));
GC_push_one(state.THREAD_FLD(r12));
GC_push_one(state.THREAD_FLD(r13));
GC_push_one(state.THREAD_FLD(r14));
GC_push_one(state.THREAD_FLD(r15));
# elif defined(POWERPC)
lo = (void *)(state.THREAD_FLD(r1) - PPC_RED_ZONE_SIZE);
# ifndef DARWIN_DONT_PARSE_STACK
*phi = GC_FindTopOfStack(state.THREAD_FLD(r1));
# endif
GC_push_one(state.THREAD_FLD(r0));
GC_push_one(state.THREAD_FLD(r2));
GC_push_one(state.THREAD_FLD(r3));
GC_push_one(state.THREAD_FLD(r4));
GC_push_one(state.THREAD_FLD(r5));
GC_push_one(state.THREAD_FLD(r6));
GC_push_one(state.THREAD_FLD(r7));
GC_push_one(state.THREAD_FLD(r8));
GC_push_one(state.THREAD_FLD(r9));
GC_push_one(state.THREAD_FLD(r10));
GC_push_one(state.THREAD_FLD(r11));
GC_push_one(state.THREAD_FLD(r12));
GC_push_one(state.THREAD_FLD(r13));
GC_push_one(state.THREAD_FLD(r14));
GC_push_one(state.THREAD_FLD(r15));
GC_push_one(state.THREAD_FLD(r16));
GC_push_one(state.THREAD_FLD(r17));
GC_push_one(state.THREAD_FLD(r18));
GC_push_one(state.THREAD_FLD(r19));
GC_push_one(state.THREAD_FLD(r20));
GC_push_one(state.THREAD_FLD(r21));
GC_push_one(state.THREAD_FLD(r22));
GC_push_one(state.THREAD_FLD(r23));
GC_push_one(state.THREAD_FLD(r24));
GC_push_one(state.THREAD_FLD(r25));
GC_push_one(state.THREAD_FLD(r26));
GC_push_one(state.THREAD_FLD(r27));
GC_push_one(state.THREAD_FLD(r28));
GC_push_one(state.THREAD_FLD(r29));
GC_push_one(state.THREAD_FLD(r30));
GC_push_one(state.THREAD_FLD(r31));
# elif defined(ARM32)
lo = (void *)state.__sp;
# ifndef DARWIN_DONT_PARSE_STACK
*phi = GC_FindTopOfStack(state.__sp);
# endif
GC_push_one(state.__r[0]);
GC_push_one(state.__r[1]);
GC_push_one(state.__r[2]);
GC_push_one(state.__r[3]);
GC_push_one(state.__r[4]);
GC_push_one(state.__r[5]);
GC_push_one(state.__r[6]);
GC_push_one(state.__r[7]);
GC_push_one(state.__r[8]);
GC_push_one(state.__r[9]);
GC_push_one(state.__r[10]);
GC_push_one(state.__r[11]);
GC_push_one(state.__r[12]);
/* GC_push_one(state.__sp); */
GC_push_one(state.__lr);
/* GC_push_one(state.__pc); */
GC_push_one(state.__cpsr);
# else
# error FIXME for non-x86 || ppc || arm architectures
# endif
} /* thread != my_thread */
# ifdef DARWIN_DONT_PARSE_STACK
/* p is guaranteed to be non-NULL regardless of GC_query_task_threads. */
*phi = (p->flags & MAIN_THREAD) != 0 ? GC_stackbottom : p->stack_end;
# endif
# ifdef DEBUG_THREADS
GC_log_printf("Darwin: Stack for thread 0x%lx = [%p,%p)\n",
(unsigned long)thread, lo, *phi);
# endif
return lo;
}
GC_INNER void GC_push_all_stacks(void)
{
int i;
ptr_t lo, hi;
task_t my_task = current_task();
mach_port_t my_thread = mach_thread_self();
GC_bool found_me = FALSE;
int nthreads = 0;
word total_size = 0;
mach_msg_type_number_t listcount = (mach_msg_type_number_t)THREAD_TABLE_SZ;
if (!GC_thr_initialized)
GC_thr_init();
# ifndef DARWIN_DONT_PARSE_STACK
if (GC_query_task_threads) {
kern_return_t kern_result;
thread_act_array_t act_list = 0;
/* Obtain the list of the threads from the kernel. */
kern_result = task_threads(my_task, &act_list, &listcount);
if (kern_result != KERN_SUCCESS)
ABORT("task_threads failed");
for (i = 0; i < (int)listcount; i++) {
thread_act_t thread = act_list[i];
lo = GC_stack_range_for(&hi, thread, NULL, FALSE, my_thread);
GC_ASSERT(lo <= hi);
total_size += hi - lo;
GC_push_all_stack(lo, hi);
nthreads++;
if (thread == my_thread)
found_me = TRUE;
mach_port_deallocate(my_task, thread);
} /* for (i=0; ...) */
vm_deallocate(my_task, (vm_address_t)act_list,
sizeof(thread_t) * listcount);
} else
# endif /* !DARWIN_DONT_PARSE_STACK */
/* else */ {
for (i = 0; i < (int)listcount; i++) {
GC_thread p;
for (p = GC_threads[i]; p != NULL; p = p->next)
if ((p->flags & FINISHED) == 0) {
thread_act_t thread = (thread_act_t)p->stop_info.mach_thread;
lo = GC_stack_range_for(&hi, thread, p, (GC_bool)p->thread_blocked,
my_thread);
GC_ASSERT(lo <= hi);
total_size += hi - lo;
GC_push_all_stack_sections(lo, hi, p->traced_stack_sect);
nthreads++;
if (thread == my_thread)
found_me = TRUE;
}
} /* for (i=0; ...) */
}
mach_port_deallocate(my_task, my_thread);
if (GC_print_stats == VERBOSE)
GC_log_printf("Pushed %d thread stacks\n", nthreads);
if (!found_me && !GC_in_thread_creation)
ABORT("Collecting from unknown thread");
GC_total_stacksize = total_size;
}
#ifndef GC_NO_THREADS_DISCOVERY
# ifdef MPROTECT_VDB
STATIC mach_port_t GC_mach_handler_thread = 0;
STATIC GC_bool GC_use_mach_handler_thread = FALSE;
GC_INNER void GC_darwin_register_mach_handler_thread(mach_port_t thread)
{
GC_mach_handler_thread = thread;
GC_use_mach_handler_thread = TRUE;
}
# endif /* MPROTECT_VDB */
# ifndef GC_MAX_MACH_THREADS
# define GC_MAX_MACH_THREADS THREAD_TABLE_SZ
# endif
struct GC_mach_thread {
thread_act_t thread;
GC_bool already_suspended;
};
struct GC_mach_thread GC_mach_threads[GC_MAX_MACH_THREADS];
STATIC int GC_mach_threads_count = 0;
/* FIXME: it is better to implement GC_mach_threads as a hash set. */
/* returns true if there's a thread in act_list that wasn't in old_list */
STATIC GC_bool GC_suspend_thread_list(thread_act_array_t act_list, int count,
thread_act_array_t old_list,
int old_count, mach_port_t my_thread)
{
int i;
int j = -1;
GC_bool changed = FALSE;
for (i = 0; i < count; i++) {
thread_act_t thread = act_list[i];
GC_bool found;
struct thread_basic_info info;
mach_msg_type_number_t outCount;
kern_return_t kern_result;
if (thread == my_thread
# ifdef MPROTECT_VDB
|| (GC_mach_handler_thread == thread && GC_use_mach_handler_thread)
# endif
) {
/* Don't add our and the handler threads. */
continue;
}
# ifdef PARALLEL_MARK
if (GC_is_mach_marker(thread))
continue; /* ignore the parallel marker threads */
# endif
# ifdef DEBUG_THREADS
GC_log_printf("Attempting to suspend thread 0x%lx\n",
(unsigned long)thread);
# endif
/* find the current thread in the old list */
found = FALSE;
{
int last_found = j; /* remember the previous found thread index */
/* Search for the thread starting from the last found one first. */
while (++j < old_count)
if (old_list[j] == thread) {
found = TRUE;
break;
}
if (!found) {
/* If not found, search in the rest (beginning) of the list. */
for (j = 0; j < last_found; j++)
if (old_list[j] == thread) {
found = TRUE;
break;
}
if (!found) {
/* add it to the GC_mach_threads list */
if (GC_mach_threads_count == GC_MAX_MACH_THREADS)
ABORT("Too many threads");
GC_mach_threads[GC_mach_threads_count].thread = thread;
/* default is not suspended */
GC_mach_threads[GC_mach_threads_count].already_suspended = FALSE;
changed = TRUE;
}
}
}
outCount = THREAD_INFO_MAX;
kern_result = thread_info(thread, THREAD_BASIC_INFO,
(thread_info_t)&info, &outCount);
if (kern_result != KERN_SUCCESS) {
/* The thread may have quit since the thread_threads() call we */
/* mark already suspended so it's not dealt with anymore later. */
if (!found)
GC_mach_threads[GC_mach_threads_count++].already_suspended = TRUE;
continue;
}
# ifdef DEBUG_THREADS
GC_log_printf("Thread state for 0x%lx = %d\n", (unsigned long)thread,
info.run_state);
# endif
if (info.suspend_count != 0) {
/* thread is already suspended. */
if (!found)
GC_mach_threads[GC_mach_threads_count++].already_suspended = TRUE;
continue;
}
# ifdef DEBUG_THREADS
GC_log_printf("Suspending 0x%lx\n", (unsigned long)thread);
# endif
kern_result = thread_suspend(thread);
if (kern_result != KERN_SUCCESS) {
/* The thread may have quit since the thread_threads() call we */
/* mark already suspended so it's not dealt with anymore later. */
if (!found)
GC_mach_threads[GC_mach_threads_count++].already_suspended = TRUE;
continue;
}
if (!found)
GC_mach_threads_count++;
}
return changed;
}
#endif /* !GC_NO_THREADS_DISCOVERY */
/* Caller holds allocation lock. */
GC_INNER void GC_stop_world(void)
{
unsigned i;
task_t my_task = current_task();
mach_port_t my_thread = mach_thread_self();
kern_return_t kern_result;
# ifdef DEBUG_THREADS
GC_log_printf("Stopping the world from thread 0x%lx\n",
(unsigned long)my_thread);
# endif
# ifdef PARALLEL_MARK
if (GC_parallel) {
/* Make sure all free list construction has stopped before we */
/* start. No new construction can start, since free list */
/* construction is required to acquire and release the GC lock */
/* before it starts, and we have the lock. */
GC_acquire_mark_lock();
GC_ASSERT(GC_fl_builder_count == 0);
/* We should have previously waited for it to become zero. */
}
# endif /* PARALLEL_MARK */
if (GC_query_task_threads) {
# ifndef GC_NO_THREADS_DISCOVERY
GC_bool changed;
thread_act_array_t act_list, prev_list;
mach_msg_type_number_t listcount, prevcount;
/* Clear out the mach threads list table. We do not need to */
/* really clear GC_mach_threads[] as it is used only in the range */
/* from 0 to GC_mach_threads_count-1, inclusive. */
GC_mach_threads_count = 0;
/* Loop stopping threads until you have gone over the whole list */
/* twice without a new one appearing. thread_create() won't */
/* return (and thus the thread stop) until the new thread exists, */
/* so there is no window whereby you could stop a thread, */
/* recognize it is stopped, but then have a new thread it created */
/* before stopping show up later. */
changed = TRUE;
prev_list = NULL;
prevcount = 0;
do {
kern_result = task_threads(my_task, &act_list, &listcount);
if (kern_result == KERN_SUCCESS) {
changed = GC_suspend_thread_list(act_list, listcount, prev_list,
prevcount, my_thread);
if (prev_list != NULL) {
for (i = 0; i < prevcount; i++)
mach_port_deallocate(my_task, prev_list[i]);
vm_deallocate(my_task, (vm_address_t)prev_list,
sizeof(thread_t) * prevcount);
}
/* Repeat while having changes. */
prev_list = act_list;
prevcount = listcount;
}
} while (changed);
GC_ASSERT(prev_list != 0);
for (i = 0; i < prevcount; i++)
mach_port_deallocate(my_task, prev_list[i]);
vm_deallocate(my_task, (vm_address_t)act_list,
sizeof(thread_t) * listcount);
# endif /* !GC_NO_THREADS_DISCOVERY */
} else {
for (i = 0; i < THREAD_TABLE_SZ; i++) {
GC_thread p;
for (p = GC_threads[i]; p != NULL; p = p->next) {
if ((p->flags & FINISHED) == 0 && !p->thread_blocked &&
p->stop_info.mach_thread != my_thread) {
kern_result = thread_suspend(p->stop_info.mach_thread);
if (kern_result != KERN_SUCCESS)
ABORT("thread_suspend failed");
}
}
}
}
# ifdef MPROTECT_VDB
if(GC_incremental) {
GC_mprotect_stop();
}
# endif
# ifdef PARALLEL_MARK
if (GC_parallel)
GC_release_mark_lock();
# endif
# ifdef DEBUG_THREADS
GC_log_printf("World stopped from 0x%lx\n", (unsigned long)my_thread);
# endif
mach_port_deallocate(my_task, my_thread);
}
GC_INLINE void GC_thread_resume(thread_act_t thread)
{
kern_return_t kern_result;
# if defined(DEBUG_THREADS) || defined(GC_ASSERTIONS)
struct thread_basic_info info;
mach_msg_type_number_t outCount = THREAD_INFO_MAX;
kern_result = thread_info(thread, THREAD_BASIC_INFO,
(thread_info_t)&info, &outCount);
if (kern_result != KERN_SUCCESS)
ABORT("thread_info failed");
# endif
# ifdef DEBUG_THREADS
GC_log_printf("Resuming thread 0x%lx with state %d\n",
(unsigned long)thread, info.run_state);
# endif
/* Resume the thread */
kern_result = thread_resume(thread);
if (kern_result != KERN_SUCCESS)
ABORT("thread_resume failed");
}
/* Caller holds allocation lock, and has held it continuously since */
/* the world stopped. */
GC_INNER void GC_start_world(void)
{
task_t my_task = current_task();
int i;
# ifdef DEBUG_THREADS
GC_log_printf("World starting\n");
# endif
# ifdef MPROTECT_VDB
if(GC_incremental) {
GC_mprotect_resume();
}
# endif
if (GC_query_task_threads) {
# ifndef GC_NO_THREADS_DISCOVERY
int j = GC_mach_threads_count;
kern_return_t kern_result;
thread_act_array_t act_list;
mach_msg_type_number_t listcount;
kern_result = task_threads(my_task, &act_list, &listcount);
if (kern_result != KERN_SUCCESS)
ABORT("task_threads failed");
for (i = 0; i < (int)listcount; i++) {
thread_act_t thread = act_list[i];
int last_found = j; /* The thread index found during the */
/* previous iteration (count value */
/* means no thread found yet). */
/* Search for the thread starting from the last found one first. */
while (++j < GC_mach_threads_count) {
if (GC_mach_threads[j].thread == thread)
break;
}
if (j >= GC_mach_threads_count) {
/* If not found, search in the rest (beginning) of the list. */
for (j = 0; j < last_found; j++) {
if (GC_mach_threads[j].thread == thread)
break;
}
}
if (j != last_found) {
/* The thread is found in GC_mach_threads. */
if (GC_mach_threads[j].already_suspended) {
# ifdef DEBUG_THREADS
GC_log_printf("Not resuming already suspended thread 0x%lx\n",
(unsigned long)thread);
# endif
} else {
GC_thread_resume(thread);
}
}
mach_port_deallocate(my_task, thread);
}
vm_deallocate(my_task, (vm_address_t)act_list,
sizeof(thread_t) * listcount);
# endif /* !GC_NO_THREADS_DISCOVERY */
} else {
mach_port_t my_thread = mach_thread_self();
for (i = 0; i < THREAD_TABLE_SZ; i++) {
GC_thread p;
for (p = GC_threads[i]; p != NULL; p = p->next) {
if ((p->flags & FINISHED) == 0 && !p->thread_blocked &&
p->stop_info.mach_thread != my_thread)
GC_thread_resume(p->stop_info.mach_thread);
}
}
mach_port_deallocate(my_task, my_thread);
}
# ifdef DEBUG_THREADS
GC_log_printf("World started\n");
# endif
}
#endif /* GC_DARWIN_THREADS */