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
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
|
/* ---------------------------------------------------------------------------
*
* (c) The GHC Team, 2006
*
* Thread-related functionality
*
* --------------------------------------------------------------------------*/
#include "PosixSource.h"
#include "Rts.h"
#include "Capability.h"
#include "Updates.h"
#include "Threads.h"
#include "STM.h"
#include "Schedule.h"
#include "Trace.h"
#include "ThreadLabels.h"
#include "Updates.h"
#include "Messages.h"
#include "RaiseAsync.h"
#include "Prelude.h"
#include "Printer.h"
#include "sm/Sanity.h"
#include "sm/Storage.h"
#include <string.h>
/* Next thread ID to allocate.
* LOCK: sched_mutex
*/
static StgThreadID next_thread_id = 1;
/* The smallest stack size that makes any sense is:
* RESERVED_STACK_WORDS (so we can get back from the stack overflow)
* + sizeofW(StgStopFrame) (the stg_stop_thread_info frame)
* + 1 (the closure to enter)
* + 1 (stg_ap_v_ret)
* + 1 (spare slot req'd by stg_ap_v_ret)
*
* A thread with this stack will bomb immediately with a stack
* overflow, which will increase its stack size.
*/
#define MIN_STACK_WORDS (RESERVED_STACK_WORDS + sizeofW(StgStopFrame) + 3)
/* ---------------------------------------------------------------------------
Create a new thread.
The new thread starts with the given stack size. Before the
scheduler can run, however, this thread needs to have a closure
(and possibly some arguments) pushed on its stack. See
pushClosure() in Schedule.h.
createGenThread() and createIOThread() (in SchedAPI.h) are
convenient packaged versions of this function.
currently pri (priority) is only used in a GRAN setup -- HWL
------------------------------------------------------------------------ */
StgTSO *
createThread(Capability *cap, nat size)
{
StgTSO *tso;
StgStack *stack;
nat stack_size;
/* sched_mutex is *not* required */
/* catch ridiculously small stack sizes */
if (size < MIN_STACK_WORDS + sizeofW(StgStack)) {
size = MIN_STACK_WORDS + sizeofW(StgStack);
}
/* The size argument we are given includes all the per-thread
* overheads:
*
* - The TSO structure
* - The STACK header
*
* This is so that we can use a nice round power of 2 for the
* default stack size (e.g. 1k), and if we're allocating lots of
* threads back-to-back they'll fit nicely in a block. It's a bit
* of a benchmark hack, but it doesn't do any harm.
*/
stack_size = round_to_mblocks(size - sizeofW(StgTSO));
stack = (StgStack *)allocate(cap, stack_size);
TICK_ALLOC_STACK(stack_size);
SET_HDR(stack, &stg_STACK_info, CCS_SYSTEM);
stack->stack_size = stack_size - sizeofW(StgStack);
stack->sp = stack->stack + stack->stack_size;
stack->dirty = 1;
tso = (StgTSO *)allocate(cap, sizeofW(StgTSO));
TICK_ALLOC_TSO();
SET_HDR(tso, &stg_TSO_info, CCS_SYSTEM);
// Always start with the compiled code evaluator
tso->what_next = ThreadRunGHC;
tso->why_blocked = NotBlocked;
tso->block_info.closure = (StgClosure *)END_TSO_QUEUE;
tso->blocked_exceptions = END_BLOCKED_EXCEPTIONS_QUEUE;
tso->bq = (StgBlockingQueue *)END_TSO_QUEUE;
tso->flags = 0;
tso->dirty = 1;
tso->_link = END_TSO_QUEUE;
tso->saved_errno = 0;
tso->bound = NULL;
tso->cap = cap;
tso->stackobj = stack;
tso->tot_stack_size = stack->stack_size;
tso->trec = NO_TREC;
#ifdef PROFILING
tso->prof.CCCS = CCS_MAIN;
#endif
// put a stop frame on the stack
stack->sp -= sizeofW(StgStopFrame);
SET_HDR((StgClosure*)stack->sp,
(StgInfoTable *)&stg_stop_thread_info,CCS_SYSTEM);
/* Link the new thread on the global thread list.
*/
ACQUIRE_LOCK(&sched_mutex);
tso->id = next_thread_id++; // while we have the mutex
tso->global_link = g0->threads;
g0->threads = tso;
RELEASE_LOCK(&sched_mutex);
// ToDo: report the stack size in the event?
traceEventCreateThread(cap, tso);
return tso;
}
/* ---------------------------------------------------------------------------
* Comparing Thread ids.
*
* This is used from STG land in the implementation of the
* instances of Eq/Ord for ThreadIds.
* ------------------------------------------------------------------------ */
int
cmp_thread(StgPtr tso1, StgPtr tso2)
{
StgThreadID id1 = ((StgTSO *)tso1)->id;
StgThreadID id2 = ((StgTSO *)tso2)->id;
if (id1 < id2) return (-1);
if (id1 > id2) return 1;
return 0;
}
/* ---------------------------------------------------------------------------
* Fetching the ThreadID from an StgTSO.
*
* This is used in the implementation of Show for ThreadIds.
* ------------------------------------------------------------------------ */
int
rts_getThreadId(StgPtr tso)
{
return ((StgTSO *)tso)->id;
}
/* -----------------------------------------------------------------------------
Remove a thread from a queue.
Fails fatally if the TSO is not on the queue.
-------------------------------------------------------------------------- */
rtsBool // returns True if we modified queue
removeThreadFromQueue (Capability *cap, StgTSO **queue, StgTSO *tso)
{
StgTSO *t, *prev;
prev = NULL;
for (t = *queue; t != END_TSO_QUEUE; prev = t, t = t->_link) {
if (t == tso) {
if (prev) {
setTSOLink(cap,prev,t->_link);
t->_link = END_TSO_QUEUE;
return rtsFalse;
} else {
*queue = t->_link;
t->_link = END_TSO_QUEUE;
return rtsTrue;
}
}
}
barf("removeThreadFromQueue: not found");
}
rtsBool // returns True if we modified head or tail
removeThreadFromDeQueue (Capability *cap,
StgTSO **head, StgTSO **tail, StgTSO *tso)
{
StgTSO *t, *prev;
rtsBool flag = rtsFalse;
prev = NULL;
for (t = *head; t != END_TSO_QUEUE; prev = t, t = t->_link) {
if (t == tso) {
if (prev) {
setTSOLink(cap,prev,t->_link);
flag = rtsFalse;
} else {
*head = t->_link;
flag = rtsTrue;
}
t->_link = END_TSO_QUEUE;
if (*tail == tso) {
if (prev) {
*tail = prev;
} else {
*tail = END_TSO_QUEUE;
}
return rtsTrue;
} else {
return flag;
}
}
}
barf("removeThreadFromMVarQueue: not found");
}
/* ----------------------------------------------------------------------------
tryWakeupThread()
Attempt to wake up a thread. tryWakeupThread is idempotent: it is
always safe to call it too many times, but it is not safe in
general to omit a call.
------------------------------------------------------------------------- */
void
tryWakeupThread (Capability *cap, StgTSO *tso)
{
traceEventThreadWakeup (cap, tso, tso->cap->no);
#ifdef THREADED_RTS
if (tso->cap != cap)
{
MessageWakeup *msg;
msg = (MessageWakeup *)allocate(cap,sizeofW(MessageWakeup));
SET_HDR(msg, &stg_MSG_TRY_WAKEUP_info, CCS_SYSTEM);
msg->tso = tso;
sendMessage(cap, tso->cap, (Message*)msg);
debugTraceCap(DEBUG_sched, cap, "message: try wakeup thread %ld on cap %d",
(lnat)tso->id, tso->cap->no);
return;
}
#endif
switch (tso->why_blocked)
{
case BlockedOnMVar:
{
if (tso->_link == END_TSO_QUEUE) {
tso->block_info.closure = (StgClosure*)END_TSO_QUEUE;
goto unblock;
} else {
return;
}
}
case BlockedOnMsgThrowTo:
{
const StgInfoTable *i;
i = lockClosure(tso->block_info.closure);
unlockClosure(tso->block_info.closure, i);
if (i != &stg_MSG_NULL_info) {
debugTraceCap(DEBUG_sched, cap, "thread %ld still blocked on throwto (%p)",
(lnat)tso->id, tso->block_info.throwto->header.info);
return;
}
// remove the block frame from the stack
ASSERT(tso->stackobj->sp[0] == (StgWord)&stg_block_throwto_info);
tso->stackobj->sp += 3;
goto unblock;
}
case BlockedOnBlackHole:
case BlockedOnSTM:
case ThreadMigrating:
goto unblock;
default:
// otherwise, do nothing
return;
}
unblock:
// just run the thread now, if the BH is not really available,
// we'll block again.
tso->why_blocked = NotBlocked;
appendToRunQueue(cap,tso);
// We used to set the context switch flag here, which would
// trigger a context switch a short time in the future (at the end
// of the current nursery block). The idea is that we have just
// woken up a thread, so we may need to load-balance and migrate
// threads to other CPUs. On the other hand, setting the context
// switch flag here unfairly penalises the current thread by
// yielding its time slice too early.
//
// The synthetic benchmark nofib/smp/chan can be used to show the
// difference quite clearly.
// cap->context_switch = 1;
}
/* ----------------------------------------------------------------------------
migrateThread
------------------------------------------------------------------------- */
void
migrateThread (Capability *from, StgTSO *tso, Capability *to)
{
traceEventMigrateThread (from, tso, to->no);
// ThreadMigrating tells the target cap that it needs to be added to
// the run queue when it receives the MSG_TRY_WAKEUP.
tso->why_blocked = ThreadMigrating;
tso->cap = to;
tryWakeupThread(from, tso);
}
/* ----------------------------------------------------------------------------
awakenBlockedQueue
wakes up all the threads on the specified queue.
------------------------------------------------------------------------- */
void
wakeBlockingQueue(Capability *cap, StgBlockingQueue *bq)
{
MessageBlackHole *msg;
const StgInfoTable *i;
ASSERT(bq->header.info == &stg_BLOCKING_QUEUE_DIRTY_info ||
bq->header.info == &stg_BLOCKING_QUEUE_CLEAN_info );
for (msg = bq->queue; msg != (MessageBlackHole*)END_TSO_QUEUE;
msg = msg->link) {
i = msg->header.info;
if (i != &stg_IND_info) {
ASSERT(i == &stg_MSG_BLACKHOLE_info);
tryWakeupThread(cap,msg->tso);
}
}
// overwrite the BQ with an indirection so it will be
// collected at the next GC.
#if defined(DEBUG) && !defined(THREADED_RTS)
// XXX FILL_SLOP, but not if THREADED_RTS because in that case
// another thread might be looking at this BLOCKING_QUEUE and
// checking the owner field at the same time.
bq->bh = 0; bq->queue = 0; bq->owner = 0;
#endif
OVERWRITE_INFO(bq, &stg_IND_info);
}
// If we update a closure that we know we BLACKHOLE'd, and the closure
// no longer points to the current TSO as its owner, then there may be
// an orphaned BLOCKING_QUEUE closure with blocked threads attached to
// it. We therefore traverse the BLOCKING_QUEUEs attached to the
// current TSO to see if any can now be woken up.
void
checkBlockingQueues (Capability *cap, StgTSO *tso)
{
StgBlockingQueue *bq, *next;
StgClosure *p;
debugTraceCap(DEBUG_sched, cap,
"collision occurred; checking blocking queues for thread %ld",
(lnat)tso->id);
for (bq = tso->bq; bq != (StgBlockingQueue*)END_TSO_QUEUE; bq = next) {
next = bq->link;
if (bq->header.info == &stg_IND_info) {
// ToDo: could short it out right here, to avoid
// traversing this IND multiple times.
continue;
}
p = bq->bh;
if (p->header.info != &stg_BLACKHOLE_info ||
((StgInd *)p)->indirectee != (StgClosure*)bq)
{
wakeBlockingQueue(cap,bq);
}
}
}
/* ----------------------------------------------------------------------------
updateThunk
Update a thunk with a value. In order to do this, we need to know
which TSO owns (or is evaluating) the thunk, in case we need to
awaken any threads that are blocked on it.
------------------------------------------------------------------------- */
void
updateThunk (Capability *cap, StgTSO *tso, StgClosure *thunk, StgClosure *val)
{
StgClosure *v;
StgTSO *owner;
const StgInfoTable *i;
i = thunk->header.info;
if (i != &stg_BLACKHOLE_info &&
i != &stg_CAF_BLACKHOLE_info &&
i != &__stg_EAGER_BLACKHOLE_info &&
i != &stg_WHITEHOLE_info) {
updateWithIndirection(cap, thunk, val);
return;
}
v = ((StgInd*)thunk)->indirectee;
updateWithIndirection(cap, thunk, val);
i = v->header.info;
if (i == &stg_TSO_info) {
owner = (StgTSO*)v;
if (owner != tso) {
checkBlockingQueues(cap, tso);
}
return;
}
if (i != &stg_BLOCKING_QUEUE_CLEAN_info &&
i != &stg_BLOCKING_QUEUE_DIRTY_info) {
checkBlockingQueues(cap, tso);
return;
}
owner = ((StgBlockingQueue*)v)->owner;
if (owner != tso) {
checkBlockingQueues(cap, tso);
} else {
wakeBlockingQueue(cap, (StgBlockingQueue*)v);
}
}
/* ---------------------------------------------------------------------------
* rtsSupportsBoundThreads(): is the RTS built to support bound threads?
* used by Control.Concurrent for error checking.
* ------------------------------------------------------------------------- */
HsBool
rtsSupportsBoundThreads(void)
{
#if defined(THREADED_RTS)
return HS_BOOL_TRUE;
#else
return HS_BOOL_FALSE;
#endif
}
/* ---------------------------------------------------------------------------
* isThreadBound(tso): check whether tso is bound to an OS thread.
* ------------------------------------------------------------------------- */
StgBool
isThreadBound(StgTSO* tso USED_IF_THREADS)
{
#if defined(THREADED_RTS)
return (tso->bound != NULL);
#endif
return rtsFalse;
}
/* -----------------------------------------------------------------------------
Stack overflow
If the thread has reached its maximum stack size, then raise the
StackOverflow exception in the offending thread. Otherwise
relocate the TSO into a larger chunk of memory and adjust its stack
size appropriately.
-------------------------------------------------------------------------- */
void
threadStackOverflow (Capability *cap, StgTSO *tso)
{
StgStack *new_stack, *old_stack;
StgUnderflowFrame *frame;
IF_DEBUG(sanity,checkTSO(tso));
if (tso->tot_stack_size >= RtsFlags.GcFlags.maxStkSize
&& !(tso->flags & TSO_BLOCKEX)) {
// NB. never raise a StackOverflow exception if the thread is
// inside Control.Exceptino.block. It is impractical to protect
// against stack overflow exceptions, since virtually anything
// can raise one (even 'catch'), so this is the only sensible
// thing to do here. See bug #767.
//
if (tso->flags & TSO_SQUEEZED) {
return;
}
// #3677: In a stack overflow situation, stack squeezing may
// reduce the stack size, but we don't know whether it has been
// reduced enough for the stack check to succeed if we try
// again. Fortunately stack squeezing is idempotent, so all we
// need to do is record whether *any* squeezing happened. If we
// are at the stack's absolute -K limit, and stack squeezing
// happened, then we try running the thread again. The
// TSO_SQUEEZED flag is set by threadPaused() to tell us whether
// squeezing happened or not.
debugTrace(DEBUG_gc,
"threadStackOverflow of TSO %ld (%p): stack too large (now %ld; max is %ld)",
(long)tso->id, tso, (long)tso->stackobj->stack_size,
RtsFlags.GcFlags.maxStkSize);
IF_DEBUG(gc,
/* If we're debugging, just print out the top of the stack */
printStackChunk(tso->stackobj->sp,
stg_min(tso->stackobj->stack + tso->stackobj->stack_size,
tso->stackobj->sp+64)));
// Send this thread the StackOverflow exception
throwToSingleThreaded(cap, tso, (StgClosure *)stackOverflow_closure);
}
// We also want to avoid enlarging the stack if squeezing has
// already released some of it. However, we don't want to get into
// a pathalogical situation where a thread has a nearly full stack
// (near its current limit, but not near the absolute -K limit),
// keeps allocating a little bit, squeezing removes a little bit,
// and then it runs again. So to avoid this, if we squeezed *and*
// there is still less than BLOCK_SIZE_W words free, then we enlarge
// the stack anyway.
if ((tso->flags & TSO_SQUEEZED) &&
((W_)(tso->stackobj->sp - tso->stackobj->stack) >= BLOCK_SIZE_W)) {
return;
}
debugTraceCap(DEBUG_sched, cap,
"allocating new stack chunk of size %d bytes",
RtsFlags.GcFlags.stkChunkSize * sizeof(W_));
old_stack = tso->stackobj;
new_stack = (StgStack*) allocate(cap, RtsFlags.GcFlags.stkChunkSize);
SET_HDR(new_stack, &stg_STACK_info, CCS_SYSTEM);
TICK_ALLOC_STACK(RtsFlags.GcFlags.stkChunkSize);
new_stack->dirty = 0; // begin clean, we'll mark it dirty below
new_stack->stack_size = RtsFlags.GcFlags.stkChunkSize - sizeofW(StgStack);
new_stack->sp = new_stack->stack + new_stack->stack_size;
tso->tot_stack_size += new_stack->stack_size;
new_stack->sp -= sizeofW(StgUnderflowFrame);
frame = (StgUnderflowFrame*)new_stack->sp;
frame->info = &stg_stack_underflow_frame_info;
frame->next_chunk = old_stack;
{
StgWord *sp;
nat chunk_words, size;
// find the boundary of the chunk of old stack we're going to
// copy to the new stack. We skip over stack frames until we
// reach the smaller of
//
// * the chunk buffer size (+RTS -kb)
// * the end of the old stack
//
for (sp = old_stack->sp;
sp < stg_min(old_stack->sp + RtsFlags.GcFlags.stkChunkBufferSize,
old_stack->stack + old_stack->stack_size); )
{
size = stack_frame_sizeW((StgClosure*)sp);
// if including this frame would exceed the size of the
// new stack (taking into account the underflow frame),
// then stop at the previous frame.
if (sp + size > old_stack->stack + (new_stack->stack_size -
sizeofW(StgUnderflowFrame))) {
break;
}
sp += size;
}
// copy the stack chunk between tso->sp and sp to
// new_tso->sp + (tso->sp - sp)
chunk_words = sp - old_stack->sp;
memcpy(/* dest */ new_stack->sp - chunk_words,
/* source */ old_stack->sp,
/* size */ chunk_words * sizeof(W_));
old_stack->sp += chunk_words;
new_stack->sp -= chunk_words;
}
// if the old stack chunk is now empty, discard it. With the
// default settings, -ki1k -kb1k, this means the first stack chunk
// will be discarded after the first overflow, being replaced by a
// non-moving 32k chunk.
if (old_stack->sp == old_stack->stack + old_stack->stack_size) {
frame->next_chunk = new_stack;
}
tso->stackobj = new_stack;
// we're about to run it, better mark it dirty
dirty_STACK(cap, new_stack);
IF_DEBUG(sanity,checkTSO(tso));
// IF_DEBUG(scheduler,printTSO(new_tso));
}
/* ---------------------------------------------------------------------------
Stack underflow - called from the stg_stack_underflow_info frame
------------------------------------------------------------------------ */
nat // returns offset to the return address
threadStackUnderflow (Capability *cap, StgTSO *tso)
{
StgStack *new_stack, *old_stack;
StgUnderflowFrame *frame;
nat retvals;
debugTraceCap(DEBUG_sched, cap, "stack underflow");
old_stack = tso->stackobj;
frame = (StgUnderflowFrame*)(old_stack->stack + old_stack->stack_size
- sizeofW(StgUnderflowFrame));
ASSERT(frame->info == &stg_stack_underflow_frame_info);
new_stack = (StgStack*)frame->next_chunk;
tso->stackobj = new_stack;
retvals = (P_)frame - old_stack->sp;
if (retvals != 0)
{
// we have some return values to copy to the old stack
if ((new_stack->sp - new_stack->stack) < retvals)
{
barf("threadStackUnderflow: not enough space for return values");
}
new_stack->sp -= retvals;
memcpy(/* dest */ new_stack->sp,
/* src */ old_stack->sp,
/* size */ retvals * sizeof(W_));
}
// empty the old stack. The GC may still visit this object
// because it is on the mutable list.
old_stack->sp = old_stack->stack + old_stack->stack_size;
// restore the stack parameters, and update tot_stack_size
tso->tot_stack_size -= old_stack->stack_size;
// we're about to run it, better mark it dirty
dirty_STACK(cap, new_stack);
return retvals;
}
/* ----------------------------------------------------------------------------
* Debugging: why is a thread blocked
* ------------------------------------------------------------------------- */
#if DEBUG
void
printThreadBlockage(StgTSO *tso)
{
switch (tso->why_blocked) {
case BlockedOnRead:
debugBelch("is blocked on read from fd %d", (int)(tso->block_info.fd));
break;
case BlockedOnWrite:
debugBelch("is blocked on write to fd %d", (int)(tso->block_info.fd));
break;
#if defined(mingw32_HOST_OS)
case BlockedOnDoProc:
debugBelch("is blocked on proc (request: %u)", tso->block_info.async_result->reqID);
break;
#endif
case BlockedOnDelay:
debugBelch("is blocked until %ld", (long)(tso->block_info.target));
break;
case BlockedOnMVar:
debugBelch("is blocked on an MVar @ %p", tso->block_info.closure);
break;
case BlockedOnBlackHole:
debugBelch("is blocked on a black hole %p",
((StgBlockingQueue*)tso->block_info.bh->bh));
break;
case BlockedOnMsgThrowTo:
debugBelch("is blocked on a throwto message");
break;
case NotBlocked:
debugBelch("is not blocked");
break;
case ThreadMigrating:
debugBelch("is runnable, but not on the run queue");
break;
case BlockedOnCCall:
debugBelch("is blocked on an external call");
break;
case BlockedOnCCall_Interruptible:
debugBelch("is blocked on an external call (but may be interrupted)");
break;
case BlockedOnSTM:
debugBelch("is blocked on an STM operation");
break;
default:
barf("printThreadBlockage: strange tso->why_blocked: %d for TSO %d (%d)",
tso->why_blocked, tso->id, tso);
}
}
void
printThreadStatus(StgTSO *t)
{
debugBelch("\tthread %4lu @ %p ", (unsigned long)t->id, (void *)t);
{
void *label = lookupThreadLabel(t->id);
if (label) debugBelch("[\"%s\"] ",(char *)label);
}
switch (t->what_next) {
case ThreadKilled:
debugBelch("has been killed");
break;
case ThreadComplete:
debugBelch("has completed");
break;
default:
printThreadBlockage(t);
}
if (t->dirty) {
debugBelch(" (TSO_DIRTY)");
}
debugBelch("\n");
}
void
printAllThreads(void)
{
StgTSO *t, *next;
nat i, g;
Capability *cap;
debugBelch("all threads:\n");
for (i = 0; i < n_capabilities; i++) {
cap = &capabilities[i];
debugBelch("threads on capability %d:\n", cap->no);
for (t = cap->run_queue_hd; t != END_TSO_QUEUE; t = t->_link) {
printThreadStatus(t);
}
}
debugBelch("other threads:\n");
for (g = 0; g < RtsFlags.GcFlags.generations; g++) {
for (t = generations[g].threads; t != END_TSO_QUEUE; t = next) {
if (t->why_blocked != NotBlocked) {
printThreadStatus(t);
}
next = t->global_link;
}
}
}
// useful from gdb
void
printThreadQueue(StgTSO *t)
{
nat i = 0;
for (; t != END_TSO_QUEUE; t = t->_link) {
printThreadStatus(t);
i++;
}
debugBelch("%d threads on queue\n", i);
}
#endif /* DEBUG */
|