aboutsummaryrefslogtreecommitdiffstats
path: root/erts/emulator/beam/erl_lock_check.c
blob: 8c7e1f36ee6087d49fd0fa4e8e05550a135bcba8 (plain) (blame)
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
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
/*
 * %CopyrightBegin%
 *
 * Copyright Ericsson AB 2005-2011. All Rights Reserved.
 *
 * The contents of this file are subject to the Erlang Public License,
 * Version 1.1, (the "License"); you may not use this file except in
 * compliance with the License. You should have received a copy of the
 * Erlang Public License along with this software. If not, it can be
 * retrieved online at http://www.erlang.org/.
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 *
 * %CopyrightEnd%
 */

/*
 * Description: A lock checker that checks that each thread acquires
 *              locks according to a predefined global lock order. The
 *              global lock order is used to prevent deadlocks. If the
 *              lock order is violated, an error message is printed
 *              and the emulator aborts. The lock checker is only
 *              intended to be enabled when debugging.
 *
 * Author: Rickard Green
 */

#ifdef HAVE_CONFIG_H
#  include "config.h"
#endif

/* Needed for VxWorks va_arg */
#include "sys.h"

#ifdef ERTS_ENABLE_LOCK_CHECK

#include "erl_lock_check.h"
#include "erl_term.h"
#include "erl_threads.h"

typedef struct {
    char *name;
    char *internal_order;
} erts_lc_lock_order_t;

/*
 * Global lock order for locks in the emulator.
 *
 * Locks early (low indexes) in the 'erts_lock_order' array should be
 * locked before locks late (high indexes) in the array. Each lock has
 * a name which is set on initialization. If multiple locks with the
 * same name are used, either an immediate Erlang term (e.g. internal
 * pid) or the address of the lock is used for internal lock order.
 * The immediate Erlang term used for internal lock order is also set
 * on initialization. Locks with small immediate Erlang terms should
 * be locked before locks with large immediate Erlang terms, and
 * locks with small addresses should be locked before locks with
 * large addresses. The immediate terms and adresses (boxed pointers)
 * are compared as unsigned integers not as Erlang terms.
 *
 * Once a spinlock or rw(spin)lock has been locked, the thread is not
 * allowed to lock mutexes, rwmutexes or process locks until all
 * spinlocks and rwlocks have been unlocked. This restriction is not
 * reflected by the lock order below, but the lock checker will still
 * check for violations of this restriction.
 */
static erts_lc_lock_order_t erts_lock_order[] = {
    /*
     *	"Lock name"				"Internal lock order
     *  					 description (NULL
     *						 if only one lock use
     *						 the lock name)"
     */
#ifdef ERTS_SMP
    {	"driver_lock",				"driver_name"		},
    {	"port_lock",				"port_id"		},
#endif
    {	"port_data_lock",			"address"		},
#ifdef ERTS_SMP
    {	"bif_timers",				NULL			},
    {	"reg_tab",				NULL			},
    {	"migration_info_update",		NULL			},
    {	"proc_main",				"pid"			},
    {   "old_code",                             "address"               },
#ifdef HIPE
    {	"hipe_mfait_lock",			NULL			},
#endif
    {	"nodes_monitors",			NULL			},
    {   "driver_list",                          NULL                    },
    {	"proc_link",				"pid"			},
    {	"proc_msgq",				"pid"			},
    {	"dist_entry",				"address"		},
    {	"dist_entry_links",			"address"		},
    {   "code_ix_queue",                        NULL                    },
    {	"proc_status",				"pid"			},
    {	"proc_tab",				NULL			},
    {   "ports_snapshot",                       NULL                    },
    {	"meta_name_tab",	         	"address"		},
    {	"meta_main_tab_slot",			"address"		},
    {	"db_tab",				"address"		},
    {	"db_tab_fix",				"address"		},
    {	"meta_main_tab_main",			NULL 			},
    {	"db_hash_slot",				"address"		},
    {	"node_table",				NULL			},
    {	"dist_table",				NULL			},
    {	"sys_tracers",				NULL			},
    {	"module_tab",				NULL			},
    {	"export_tab",				NULL			},
    {	"fun_tab",				NULL			},
    {	"environ",				NULL			},
#endif
    {	"efile_drv",				"address"		},
#if defined(ENABLE_CHILD_WAITER_THREAD) || defined(ERTS_SMP)
    {	"child_status",				NULL			},
#endif
#ifdef __WIN32__
    {	"sys_driver_data_lock",			NULL 			},
#endif
    {	"drv_ev_state_grow",			NULL,   		},
    {	"drv_ev_state",				"address"		},
    {	"safe_hash",				"address"		},
    {   "pollset_rm_list",                      NULL                    },
    {   "removed_fd_pre_alloc_lock",            "address"               },
    {   "state_prealloc",                       NULL                    },
    {	"schdlr_sspnd",				NULL			},
    {	"run_queue",				"address"		},
    {	"cpu_info",				NULL			},
    {	"pollset",				"address"		},
#ifdef __WIN32__
    {	"pollwaiter",				"address"		},
    {   "break_waiter_lock",                    NULL                    },
#endif /* __WIN32__ */
    {	"alcu_init_atoms",			NULL			},
    {	"mseg_init_atoms",			NULL			},
    {	"drv_tsd",				NULL			},
    {	"async_enq_mtx",			NULL			},
#ifdef ERTS_SMP
    {	"sys_msg_q", 				NULL			},
    {	"atom_tab",				NULL			},
    {	"make_ref",				NULL			},
    {	"misc_op_list_pre_alloc_lock",		"address"		},
    {	"message_pre_alloc_lock",		"address"		},
    {	"ptimer_pre_alloc_lock",		"address",		},
    {	"btm_pre_alloc_lock",			NULL,			},
    {	"dist_entry_out_queue",			"address"		},
#endif
    {	"mtrace_op",				NULL			},
    {	"instr_x",				NULL			},
    {	"instr",				NULL			},
    {	"alcu_allocator",			"index"			},
    {	"sbmbc_alloc",				"index"			},
    {	"mseg",					NULL			},
#if HALFWORD_HEAP
    {	"pmmap",				NULL			},
#endif
#ifdef ERTS_SMP
    {	"port_task_pre_alloc_lock",		"address"		},
    {	"port_taskq_pre_alloc_lock",		"address"		},
    {	"proclist_pre_alloc_lock",		"address"		},
    {	"port_tasks_lock",			NULL			},
    {   "get_free_port",                        NULL                    },
    {	"port_state",			        "address"		},
    {	"xports_list_pre_alloc_lock",		"address"		},
    {	"inet_buffer_stack_lock",		NULL			},
    {	"gc_info",				NULL			},
    {	"io_wake",				NULL			},
    {	"timer_wheel",				NULL			},
    {	"system_block",				NULL			},
    {	"timeofday",				NULL			},
    {	"breakpoints",				NULL			},
    {	"pollsets_lock",			NULL			},
    {	"pix_lock",				"address"		},
    {	"run_queues_lists",			NULL			},
    {	"sched_stat",				NULL			},
#endif
    {	"async_init_mtx",			NULL			},
#ifdef ERTS_SMP
    {	"proc_lck_qs_alloc",			NULL 			},
#endif
#ifdef __WIN32__
#ifdef DEBUG
    {   "save_ops_lock",                        NULL                    },
#endif
#endif
    {	"mtrace_buf",				NULL			},
    {	"erts_alloc_hard_debug",		NULL			}
};

#define ERTS_LOCK_ORDER_SIZE \
  (sizeof(erts_lock_order)/sizeof(erts_lc_lock_order_t))

#define LOCK_IS_TYPE_ORDER_VIOLATION(LCK_FLG, LCKD_FLG)			\
  (((LCKD_FLG) & (ERTS_LC_FLG_LT_SPINLOCK|ERTS_LC_FLG_LT_RWSPINLOCK))	\
   && ((LCK_FLG)							\
       & ERTS_LC_FLG_LT_ALL						\
       & ~(ERTS_LC_FLG_LT_SPINLOCK|ERTS_LC_FLG_LT_RWSPINLOCK)))

static __decl_noreturn void  __noreturn lc_abort(void);

static char *
lock_type(Uint16 flags)
{
    switch (flags & ERTS_LC_FLG_LT_ALL) {
    case ERTS_LC_FLG_LT_SPINLOCK:	return "[spinlock]";
    case ERTS_LC_FLG_LT_RWSPINLOCK:	return "[rw(spin)lock]";
    case ERTS_LC_FLG_LT_MUTEX:		return "[mutex]";
    case ERTS_LC_FLG_LT_RWMUTEX:	return "[rwmutex]";
    case ERTS_LC_FLG_LT_PROCLOCK:	return "[proclock]";
    default:				return "";
    }
}

static char *
rw_op_str(Uint16 flags)
{
    switch (flags & ERTS_LC_FLG_LO_READ_WRITE) {
    case ERTS_LC_FLG_LO_READ_WRITE:
	return " (rw)";
    case ERTS_LC_FLG_LO_READ:
	return " (r)";
    case ERTS_LC_FLG_LO_WRITE:
	erts_fprintf(stderr, "\nInternal error\n");
	lc_abort();
    default:
	break;
    }
    return "";
}

typedef struct erts_lc_locked_lock_t_ erts_lc_locked_lock_t;
struct erts_lc_locked_lock_t_ {
    erts_lc_locked_lock_t *next;
    erts_lc_locked_lock_t *prev;
    UWord extra;
    Sint16 id;
    Uint16 flags;
};

typedef struct {
    erts_lc_locked_lock_t *first;
    erts_lc_locked_lock_t *last;
} erts_lc_locked_lock_list_t;

typedef struct erts_lc_locked_locks_t_ erts_lc_locked_locks_t;
struct erts_lc_locked_locks_t_ {
    char *thread_name;
    erts_tid_t tid;
    erts_lc_locked_locks_t *next;
    erts_lc_locked_locks_t *prev;
    erts_lc_locked_lock_list_t locked;
    erts_lc_locked_lock_list_t required;
};

typedef union erts_lc_free_block_t_ erts_lc_free_block_t;
union erts_lc_free_block_t_ {
    erts_lc_free_block_t *next;
    erts_lc_locked_lock_t lock;
};

static ethr_tsd_key locks_key;

static erts_lc_locked_locks_t *erts_locked_locks;

static erts_lc_free_block_t *free_blocks;

#ifdef ERTS_LC_STATIC_ALLOC
#define ERTS_LC_FB_CHUNK_SIZE 10000
#else
#define ERTS_LC_FB_CHUNK_SIZE 10
#endif

static ethr_spinlock_t free_blocks_lock;

static ERTS_INLINE void
lc_lock(void)
{
    ethr_spin_lock(&free_blocks_lock);
}

static ERTS_INLINE void
lc_unlock(void)
{
    ethr_spin_unlock(&free_blocks_lock);
}

static ERTS_INLINE void lc_free(void *p)
{
    erts_lc_free_block_t *fb = (erts_lc_free_block_t *) p;
#ifdef DEBUG
    memset((void *) p, 0xdf, sizeof(erts_lc_free_block_t));
#endif
    lc_lock();
    fb->next = free_blocks;
    free_blocks = fb;
    lc_unlock();   
}

#ifdef ERTS_LC_STATIC_ALLOC

static void *lc_core_alloc(void)
{
    lc_unlock();
    erts_fprintf(stderr, "Lock checker out of memory!\n");
    lc_abort();
}

#else

static void *lc_core_alloc(void)
{
    int i;
    erts_lc_free_block_t *fbs;
    lc_unlock();
    fbs = (erts_lc_free_block_t *) malloc(sizeof(erts_lc_free_block_t)
					  * ERTS_LC_FB_CHUNK_SIZE);
    if (!fbs) {
	erts_fprintf(stderr, "Lock checker failed to allocate memory!\n");
	lc_abort();
    }
    for (i = 1; i < ERTS_LC_FB_CHUNK_SIZE - 1; i++) {
#ifdef DEBUG
	memset((void *) &fbs[i], 0xdf, sizeof(erts_lc_free_block_t));
#endif
	fbs[i].next = &fbs[i+1];
    }
#ifdef DEBUG
    memset((void *) &fbs[ERTS_LC_FB_CHUNK_SIZE-1],
	   0xdf, sizeof(erts_lc_free_block_t));
#endif
    lc_lock();
    fbs[ERTS_LC_FB_CHUNK_SIZE-1].next = free_blocks;
    free_blocks = &fbs[1];
    return (void *) &fbs[0];
}

#endif

static ERTS_INLINE void *lc_alloc(void)
{
    void *res;
    lc_lock();
    if (!free_blocks)
	res = lc_core_alloc();
    else {
	res = (void *) free_blocks;
	free_blocks = free_blocks->next;
    }
    lc_unlock();
    return res;
}


static erts_lc_locked_locks_t *
create_locked_locks(char *thread_name)
{
    erts_lc_locked_locks_t *l_lcks = malloc(sizeof(erts_lc_locked_locks_t));
    if (!l_lcks)
	lc_abort();

    l_lcks->thread_name = strdup(thread_name ? thread_name : "unknown");
    if (!l_lcks->thread_name)
	lc_abort();

    l_lcks->tid = erts_thr_self();
    l_lcks->required.first = NULL;
    l_lcks->required.last = NULL;
    l_lcks->locked.first = NULL;
    l_lcks->locked.last = NULL;
    l_lcks->prev = NULL;
    lc_lock();
    l_lcks->next = erts_locked_locks;
    if (erts_locked_locks)
	erts_locked_locks->prev = l_lcks;
    erts_locked_locks = l_lcks;
    lc_unlock();
    erts_tsd_set(locks_key, (void *) l_lcks);
    return l_lcks;
}

static void
destroy_locked_locks(erts_lc_locked_locks_t *l_lcks)
{
    ASSERT(l_lcks->thread_name);
    free((void *) l_lcks->thread_name);
    ASSERT(l_lcks->required.first == NULL);
    ASSERT(l_lcks->required.last == NULL);
    ASSERT(l_lcks->locked.first == NULL);
    ASSERT(l_lcks->locked.last == NULL);

    lc_lock();
    if (l_lcks->prev)
	l_lcks->prev->next = l_lcks->next;
    else {
	ASSERT(erts_locked_locks == l_lcks);
	erts_locked_locks = l_lcks->next;
    }

    if (l_lcks->next)
	l_lcks->next->prev = l_lcks->prev;
    lc_unlock();

    free((void *) l_lcks);

}

static ERTS_INLINE erts_lc_locked_locks_t *
get_my_locked_locks(void)
{
    return erts_tsd_get(locks_key);
}

static ERTS_INLINE erts_lc_locked_locks_t *
make_my_locked_locks(void)
{
    erts_lc_locked_locks_t *l_lcks = get_my_locked_locks();
    if (l_lcks)
	return l_lcks;
    else
	return create_locked_locks(NULL);
}

static ERTS_INLINE erts_lc_locked_lock_t *
new_locked_lock(erts_lc_lock_t *lck, Uint16 op_flags)
{
    erts_lc_locked_lock_t *l_lck = (erts_lc_locked_lock_t *) lc_alloc();
    l_lck->next = NULL;
    l_lck->prev = NULL;
    l_lck->id = lck->id;
    l_lck->extra = lck->extra;
    l_lck->flags = lck->flags | op_flags;
    return l_lck;
}

static void
print_lock2(char *prefix, Sint16 id, Wterm extra, Uint16 flags, char *suffix)
{
    char *lname = (0 <= id && id < ERTS_LOCK_ORDER_SIZE
		   ? erts_lock_order[id].name
		   : "unknown");
    if (is_not_immed(extra))
	erts_fprintf(stderr,
		     "%s'%s:%p%s'%s%s",
		     prefix,
		     lname,
		     _unchecked_boxed_val(extra),
		     lock_type(flags),
		     rw_op_str(flags),
		     suffix);
    else
	erts_fprintf(stderr,
		     "%s'%s:%T%s'%s%s",
		     prefix,
		     lname,
		     extra,
		     lock_type(flags),
		     rw_op_str(flags),
		     suffix);
}

static void
print_lock(char *prefix, erts_lc_lock_t *lck, char *suffix)
{
    print_lock2(prefix, lck->id, lck->extra, lck->flags, suffix);
}

static void
print_curr_locks(erts_lc_locked_locks_t *l_lcks)
{
    erts_lc_locked_lock_t *l_lck;
    if (!l_lcks || !l_lcks->locked.first)
	erts_fprintf(stderr,
		     "Currently no locks are locked by the %s thread.\n",
		     l_lcks->thread_name);
    else {
	erts_fprintf(stderr,
		     "Currently these locks are locked by the %s thread:\n",
		     l_lcks->thread_name);
	for (l_lck = l_lcks->locked.first; l_lck; l_lck = l_lck->next)
	    print_lock2("  ", l_lck->id, l_lck->extra, l_lck->flags, "\n");
    }
}

static void
print_lock_order(void)
{
    int i;
    erts_fprintf(stderr, "Lock order:\n");
    for (i = 1; i < ERTS_LOCK_ORDER_SIZE; i++) {
	if (erts_lock_order[i].internal_order)
	    erts_fprintf(stderr,
			 "  %s:%s\n",
			 erts_lock_order[i].name,
			 erts_lock_order[i].internal_order);
	else
	    erts_fprintf(stderr, "  %s\n", erts_lock_order[i].name);
    }
}

static void
uninitialized_lock(void)
{
    erts_fprintf(stderr, "Performing operations on uninitialized lock!\n");
    print_curr_locks(get_my_locked_locks());
    lc_abort();
}

static void
lock_twice(char *prefix, erts_lc_locked_locks_t *l_lcks, erts_lc_lock_t *lck,
	   Uint16 op_flags)
{
    erts_fprintf(stderr, "%s%s", prefix, rw_op_str(op_flags));
    print_lock(" ", lck, " lock which is already locked by thread!\n");
    print_curr_locks(l_lcks);
    lc_abort();
}

static void
unlock_op_mismatch(erts_lc_locked_locks_t *l_lcks, erts_lc_lock_t *lck,
		   Uint16 op_flags)
{
    erts_fprintf(stderr, "Unlocking%s ", rw_op_str(op_flags));
    print_lock("", lck, " lock which mismatch previous lock operation!\n");
    print_curr_locks(l_lcks);
    lc_abort();
}

static void
unlock_of_not_locked(erts_lc_locked_locks_t *l_lcks, erts_lc_lock_t *lck)
{
    print_lock("Unlocking ", lck, " lock which is not locked by thread!\n");
    print_curr_locks(l_lcks);
    lc_abort();
}

static void
lock_order_violation(erts_lc_locked_locks_t *l_lcks, erts_lc_lock_t *lck)
{
    print_lock("Lock order violation occured when locking ", lck, "!\n");
    print_curr_locks(l_lcks);
    print_lock_order();
    lc_abort();
}

static void
type_order_violation(char *op, erts_lc_locked_locks_t *l_lcks,
		     erts_lc_lock_t *lck)
{
    erts_fprintf(stderr, "Lock type order violation occured when ");
    print_lock(op, lck, "!\n");
    ASSERT(l_lcks);
    print_curr_locks(l_lcks);
    lc_abort();
}

static void
lock_mismatch(erts_lc_locked_locks_t *l_lcks, int exact,
	      int failed_have, erts_lc_lock_t *have, int have_len,
	      int failed_have_not, erts_lc_lock_t *have_not, int have_not_len)
{
    int i;
    erts_fprintf(stderr, "Lock mismatch found!\n");
    if (failed_have >= 0) {
	ASSERT(have && have_len > failed_have);
	print_lock2("At least the ",
		   have[failed_have].id, have[failed_have].extra, 0,
		   " lock is not locked when it should have been\n");
    }
    else if (failed_have_not >= 0) {
	ASSERT(have_not && have_not_len > failed_have_not);
	print_lock2("At least the ",
		    have_not[failed_have_not].id,
		    have_not[failed_have_not].extra,
		    0,
		    " lock is locked when it should not have been\n");
    }
    if (exact) {
	if (!have || have_len <= 0)
	    erts_fprintf(stderr,
			 "Thread should not have any locks locked at all\n");
	else {
	    erts_fprintf(stderr,
			 "Thread should have these and only these locks "
			 "locked:\n");
	    for (i = 0; i < have_len; i++)
		print_lock2("  ", have[i].id, have[i].extra, 0, "\n");
	}
    }
    else {
	if (have && have_len > 0) {
	    erts_fprintf(stderr,
			 "Thread should at least have these locks locked:\n");
	    for (i = 0; i < have_len; i++)
		print_lock2("  ", have[i].id, have[i].extra, 0, "\n");
	}
	if (have_not && have_not_len > 0) {
	    erts_fprintf(stderr,
			 "Thread should at least not have these locks "
			 "locked:\n");
	    for (i = 0; i < have_not_len; i++)
		print_lock2("  ", have_not[i].id, have_not[i].extra, 0, "\n");
	}
    }
    print_curr_locks(l_lcks);
    lc_abort();
}

static void
unlock_of_required_lock(erts_lc_locked_locks_t *l_lcks, erts_lc_lock_t *lck)
{
    print_lock("Unlocking required ", lck, " lock!\n");
    print_curr_locks(l_lcks);
    lc_abort();
}

static void
unrequire_of_not_required_lock(erts_lc_locked_locks_t *l_lcks, erts_lc_lock_t *lck)
{
    print_lock("Unrequire on ", lck, " lock not required!\n");
    print_curr_locks(l_lcks);
    lc_abort();
}

static void
require_twice(erts_lc_locked_locks_t *l_lcks, erts_lc_lock_t *lck)
{
    print_lock("Require on ", lck, " lock already required!\n");
    print_curr_locks(l_lcks);
    lc_abort();
}

static void
required_not_locked(erts_lc_locked_locks_t *l_lcks, erts_lc_lock_t *lck)
{
    print_lock("Required ", lck, " lock not locked!\n");
    print_curr_locks(l_lcks);
    lc_abort();
}


static void
thread_exit_handler(void)
{
    erts_lc_locked_locks_t *l_lcks = get_my_locked_locks();
    if (l_lcks) {
	if (l_lcks->locked.first) {
	    erts_fprintf(stderr,
			 "Thread exiting while having locked locks!\n");
	    print_curr_locks(l_lcks);
	    lc_abort();
	}
	destroy_locked_locks(l_lcks);
	/* erts_tsd_set(locks_key, NULL); */
    }
}

static __decl_noreturn void
lc_abort(void)
{
#ifdef __WIN32__
    DebugBreak();
#else
    abort();
#endif
}

void
erts_lc_set_thread_name(char *thread_name)
{
    erts_lc_locked_locks_t *l_lcks = get_my_locked_locks();
    if (!l_lcks)
	(void) create_locked_locks(thread_name);
    else {
	ASSERT(l_lcks->thread_name);
	free((void *) l_lcks->thread_name);
	l_lcks->thread_name = strdup(thread_name ? thread_name : "unknown");
	if (!l_lcks->thread_name)
	    lc_abort();
    }
}

int
erts_lc_assert_failed(char *file, int line, char *assertion)
{
    erts_fprintf(stderr, "%s:%d: Lock check assertion \"%s\" failed!\n",
		 file, line, assertion);
    print_curr_locks(get_my_locked_locks());
    lc_abort();
    return 0;
}

void erts_lc_fail(char *fmt, ...)
{
    va_list args;
    erts_fprintf(stderr, "Lock check failed: ");
    va_start(args, fmt);
    erts_vfprintf(stderr, fmt, args);
    va_end(args);
    erts_fprintf(stderr, "\n");
    print_curr_locks(get_my_locked_locks());
    lc_abort();
}


Sint16
erts_lc_get_lock_order_id(char *name)
{
    int i;

    if (!name || name[0] == '\0')
	erts_fprintf(stderr, "Missing lock name\n");
    else {
	for (i = 0; i < ERTS_LOCK_ORDER_SIZE; i++)
	    if (strcmp(erts_lock_order[i].name, name) == 0)
		return i;
	erts_fprintf(stderr,
		     "Lock name '%s' missing in lock order "
		     "(update erl_lock_check.c)\n",
		     name);
    }
    lc_abort();
    return (Sint16) -1;
}


static int
find_lock(erts_lc_locked_lock_t **l_lcks, erts_lc_lock_t *lck)
{
    erts_lc_locked_lock_t *l_lck = *l_lcks;

    if (l_lck) {
	if (l_lck->id == lck->id && l_lck->extra == lck->extra) {
	    if ((l_lck->flags & lck->flags) == lck->flags)
		return 1;
	    return 0;
	}
	else if (l_lck->id < lck->id
		 || (l_lck->id == lck->id
		     && l_lck->extra < lck->extra)) {
	    for (l_lck = l_lck->next; l_lck; l_lck = l_lck->next) {
		if (l_lck->id > lck->id
		    || (l_lck->id == lck->id
			&& l_lck->extra >= lck->extra)) {
		    *l_lcks = l_lck;
		    if (l_lck->id == lck->id
			&& l_lck->extra == lck->extra
			&& ((l_lck->flags & lck->flags) == lck->flags))
			    return 1;
		    return 0;
		}
	    }
	}
	else {
	    for (l_lck = l_lck->prev; l_lck; l_lck = l_lck->prev) {
		if (l_lck->id < lck->id
		    || (l_lck->id == lck->id
			&& l_lck->extra <= lck->extra)) {
		    *l_lcks = l_lck;
		    if (l_lck->id == lck->id
			&& l_lck->extra == lck->extra
			&& ((l_lck->flags & lck->flags) == lck->flags))
			return 1;
		    return 0;
		}
	    }
	}
    }
    return 0;
}

static int
find_id(erts_lc_locked_lock_t **l_lcks, Sint16 id)
{
    erts_lc_locked_lock_t *l_lck = *l_lcks;

    if (l_lck) {
	if (l_lck->id == id)
	    return 1;
	else if (l_lck->id < id) {
	    for (l_lck = l_lck->next; l_lck; l_lck = l_lck->next) {
		if (l_lck->id >= id) {
		    *l_lcks = l_lck;
		    if (l_lck->id == id)
			return 1;
		    return 0;
		}
	    }
	}
	else {
	    for (l_lck = l_lck->prev; l_lck; l_lck = l_lck->prev) {
		if (l_lck->id <= id) {
		    *l_lcks = l_lck;
		    if (l_lck->id == id)
			return 1;
		    return 0;
		}
	    }
	}
    }
    return 0;
}

void
erts_lc_have_locks(int *resv, erts_lc_lock_t *locks, int len)
{
    erts_lc_locked_locks_t *l_lcks = get_my_locked_locks();
    int i;

    if (!l_lcks) {
	for (i = 0; i < len; i++)
	    resv[i] = 0;
    }
    else {
	erts_lc_locked_lock_t *l_lck = l_lcks->locked.first;
	for (i = 0; i < len; i++)
	    resv[i] = find_lock(&l_lck, &locks[i]);
    }
}

void
erts_lc_have_lock_ids(int *resv, int *ids, int len)
{
    erts_lc_locked_locks_t *l_lcks = get_my_locked_locks();
    int i;

    if (!l_lcks) {
	for (i = 0; i < len; i++)
	    resv[i] = 0;
    }
    else {
	erts_lc_locked_lock_t *l_lck = l_lcks->locked.first;
	for (i = 0; i < len; i++)
	    resv[i] = find_id(&l_lck, ids[i]);
    }
}

void
erts_lc_check(erts_lc_lock_t *have, int have_len,
	      erts_lc_lock_t *have_not, int have_not_len)
{
    int i;
    erts_lc_locked_locks_t *l_lcks = get_my_locked_locks();
    erts_lc_locked_lock_t *l_lck;
    
    if (have && have_len > 0) {
	if (!l_lcks)
	    lock_mismatch(NULL, 0,
			  -1, have, have_len,
			  -1, have_not, have_not_len);
	l_lck = l_lcks->locked.first;
	for (i = 0; i < have_len; i++) {
	    if (!find_lock(&l_lck, &have[i]))
		lock_mismatch(l_lcks, 0,
			      i, have, have_len,
			      -1, have_not, have_not_len);
	}
    }
    if (have_not && have_not_len > 0 && l_lcks) {
	l_lck = l_lcks->locked.first;
	for (i = 0; i < have_not_len; i++) {
	    if (find_lock(&l_lck, &have_not[i]))
		lock_mismatch(l_lcks, 0,
			      -1, have, have_len,
			      i, have_not, have_not_len);
	}
    }
}

void
erts_lc_check_exact(erts_lc_lock_t *have, int have_len)
{
    erts_lc_locked_locks_t *l_lcks = get_my_locked_locks();
    if (!l_lcks) {
	if (have && have_len > 0)
	    lock_mismatch(NULL, 1,
			  -1, have, have_len,
			  -1, NULL, 0);
    }
    else {
	int i;
	erts_lc_locked_lock_t *l_lck = l_lcks->locked.first;
	for (i = 0; i < have_len; i++) {
	    if (!find_lock(&l_lck, &have[i]))
		lock_mismatch(l_lcks, 1,
			      i, have, have_len,
			      -1, NULL, 0);
	}
	for (i = 0, l_lck = l_lcks->locked.first; l_lck; l_lck = l_lck->next)
	    i++;
	if (i != have_len)
	    lock_mismatch(l_lcks, 1,
			  -1, have, have_len,
			  -1, NULL, 0);
    }
}

void
erts_lc_check_no_locked_of_type(Uint16 flags)
{
    erts_lc_locked_locks_t *l_lcks = get_my_locked_locks();
    if (l_lcks) {
	erts_lc_locked_lock_t *l_lck = l_lcks->locked.first;
	for (l_lck = l_lcks->locked.first; l_lck; l_lck = l_lck->next) {
	    if (l_lck->flags & flags) {
		erts_fprintf(stderr,
			     "Locked lock of type %s found which isn't "
			     "allowed here!\n",
			     lock_type(l_lck->flags));
		print_curr_locks(l_lcks);
		lc_abort();
	    }
	}
    }
}

int
erts_lc_trylock_force_busy_flg(erts_lc_lock_t *lck, Uint16 op_flags)
{
#ifdef ERTS_LC_DO_NOT_FORCE_BUSY_TRYLOCK_ON_LOCK_ORDER_VIOLATION
    return 0;
#else
    /*
     * Force busy trylock if locking doesn't follow lock order.
     * This in order to make sure that caller can handle
     * the situation without causing a lock order violation.
     */
    erts_lc_locked_locks_t *l_lcks;

    if (lck->inited != ERTS_LC_INITITALIZED)
	uninitialized_lock();

    if (lck->id < 0)
	return 0;

    l_lcks = get_my_locked_locks();

    if (!l_lcks || !l_lcks->locked.first) {
	ASSERT(!l_lcks || !l_lcks->locked.last);
	return 0;
    }
    else {
	erts_lc_locked_lock_t *tl_lck;

	ASSERT(l_lcks->locked.last);

#if 0 /* Ok when trylocking I guess... */
	if (LOCK_IS_TYPE_ORDER_VIOLATION(lck->flags, l_lcks->locked.last->flags))
	    type_order_violation("trylocking ", l_lcks, lck);
#endif

	if (l_lcks->locked.last->id < lck->id
	    || (l_lcks->locked.last->id == lck->id
		&& l_lcks->locked.last->extra < lck->extra))
	    return 0;

	/*
	 * Lock order violation
	 */


	/* Check that we are not trying to lock this lock twice */
	for (tl_lck = l_lcks->locked.last; tl_lck; tl_lck = tl_lck->prev) {
	    if (tl_lck->id < lck->id
		|| (tl_lck->id == lck->id && tl_lck->extra <= lck->extra)) {
		if (tl_lck->id == lck->id && tl_lck->extra == lck->extra)
		    lock_twice("Trylocking", l_lcks, lck, op_flags);
		break;
	    }
	}

#ifndef ERTS_LC_ALLWAYS_FORCE_BUSY_TRYLOCK_ON_LOCK_ORDER_VIOLATION
	/* We only force busy if a lock order violation would occur
	   and when on an even millisecond. */
	{
	    SysTimeval tv;
	    sys_gettimeofday(&tv);

	    if ((tv.tv_usec / 1000) & 1)
		return 0;
	}
#endif

	return 1;
    }
#endif
}

void erts_lc_trylock_flg(int locked, erts_lc_lock_t *lck, Uint16 op_flags)
{
    erts_lc_locked_locks_t *l_lcks;
    erts_lc_locked_lock_t *l_lck;

    if (lck->inited != ERTS_LC_INITITALIZED)
	uninitialized_lock();

    if (lck->id < 0)
	return;

    l_lcks = make_my_locked_locks();
    l_lck = locked ? new_locked_lock(lck, op_flags) : NULL;

    if (!l_lcks->locked.last) {
	ASSERT(!l_lcks->locked.first);
	if (locked)
	    l_lcks->locked.first = l_lcks->locked.last = l_lck;
    }
    else {
	erts_lc_locked_lock_t *tl_lck;
#if 0 /* Ok when trylocking I guess... */
	if (LOCK_IS_TYPE_ORDER_VIOLATION(lck->flags, l_lcks->locked.last->flags))
	    type_order_violation("trylocking ", l_lcks, lck);
#endif

	for (tl_lck = l_lcks->locked.last; tl_lck; tl_lck = tl_lck->prev) {
	    if (tl_lck->id < lck->id
		|| (tl_lck->id == lck->id && tl_lck->extra <= lck->extra)) {
		if (tl_lck->id == lck->id && tl_lck->extra == lck->extra)
		    lock_twice("Trylocking", l_lcks, lck, op_flags);
		if (locked) {
		    l_lck->next = tl_lck->next;
		    l_lck->prev = tl_lck;
		    if (tl_lck->next)
			tl_lck->next->prev = l_lck;
		    else
			l_lcks->locked.last = l_lck;
		    tl_lck->next = l_lck;
		}
		return;
	    }
	}

	if (locked) {
	    l_lck->next = l_lcks->locked.first;
	    l_lcks->locked.first->prev = l_lck;
	    l_lcks->locked.first = l_lck;
	}
    }

}

void erts_lc_require_lock_flg(erts_lc_lock_t *lck, Uint16 op_flags)
{
    erts_lc_locked_locks_t *l_lcks = make_my_locked_locks();
    erts_lc_locked_lock_t *l_lck = l_lcks->locked.first;
    if (!find_lock(&l_lck, lck))
	required_not_locked(l_lcks, lck);
    l_lck = new_locked_lock(lck, op_flags);
    if (!l_lcks->required.last) {
	ASSERT(!l_lcks->required.first);
	l_lck->next = l_lck->prev = NULL;
	l_lcks->required.first = l_lcks->required.last = l_lck;
    }
    else {
	erts_lc_locked_lock_t *l_lck2;
	ASSERT(l_lcks->required.first);
	for (l_lck2 = l_lcks->required.last;
	     l_lck2;
	     l_lck2 = l_lck2->prev) {
	    if (l_lck2->id < lck->id
		|| (l_lck2->id == lck->id && l_lck2->extra < lck->extra))
		break;
	    else if (l_lck2->id == lck->id && l_lck2->extra == lck->extra)
		require_twice(l_lcks, lck);
	}
	if (!l_lck2) {
	    l_lck->next = l_lcks->required.first;
	    l_lck->prev = NULL;
	    l_lcks->required.first->prev = l_lck;
	    l_lcks->required.first = l_lck;
	}
	else {
	    l_lck->next = l_lck2->next;
	    if (l_lck->next) {
		ASSERT(l_lcks->required.last != l_lck2);
		l_lck->next->prev = l_lck;
	    }
	    else {
		ASSERT(l_lcks->required.last == l_lck2);
		l_lcks->required.last = l_lck;
	    }
	    l_lck->prev = l_lck2;
	    l_lck2->next = l_lck;		
	}
    }
}

void erts_lc_unrequire_lock_flg(erts_lc_lock_t *lck, Uint16 op_flags)
{
    erts_lc_locked_locks_t *l_lcks = make_my_locked_locks();
    erts_lc_locked_lock_t *l_lck = l_lcks->locked.first;
    if (!find_lock(&l_lck, lck))
	required_not_locked(l_lcks, lck);
    l_lck = l_lcks->required.first;
    if (!find_lock(&l_lck, lck))
	unrequire_of_not_required_lock(l_lcks, lck);
    if (l_lck->prev) {
	ASSERT(l_lcks->required.first != l_lck);
	l_lck->prev->next = l_lck->next;
    }
    else {
	ASSERT(l_lcks->required.first == l_lck);
	l_lcks->required.first = l_lck->next;
    }
    if (l_lck->next) {
	ASSERT(l_lcks->required.last != l_lck);
	l_lck->next->prev = l_lck->prev;
    }
    else {
	ASSERT(l_lcks->required.last == l_lck);
	l_lcks->required.last = l_lck->prev;
    }
    lc_free((void *) l_lck);
}

void erts_lc_lock_flg(erts_lc_lock_t *lck, Uint16 op_flags)
{
    erts_lc_locked_locks_t *l_lcks;
    erts_lc_locked_lock_t *l_lck;

    if (lck->inited != ERTS_LC_INITITALIZED)
	uninitialized_lock();

    if (lck->id < 0)
	return;

    l_lcks = make_my_locked_locks();
    l_lck = new_locked_lock(lck, op_flags);

    if (!l_lcks->locked.last) {
	ASSERT(!l_lcks->locked.first);
	l_lcks->locked.last = l_lcks->locked.first = l_lck;
    }
    else if (l_lcks->locked.last->id < lck->id
	     || (l_lcks->locked.last->id == lck->id
		 && l_lcks->locked.last->extra < lck->extra)) {
	if (LOCK_IS_TYPE_ORDER_VIOLATION(lck->flags, l_lcks->locked.last->flags))
	    type_order_violation("locking ", l_lcks, lck);
	l_lck->prev = l_lcks->locked.last;
	l_lcks->locked.last->next = l_lck;
	l_lcks->locked.last = l_lck;
    }
    else if (l_lcks->locked.last->id == lck->id && l_lcks->locked.last->extra == lck->extra)
	lock_twice("Locking", l_lcks, lck, op_flags);
    else
	lock_order_violation(l_lcks, lck);
}

void erts_lc_unlock_flg(erts_lc_lock_t *lck, Uint16 op_flags)
{
    erts_lc_locked_locks_t *l_lcks;
    erts_lc_locked_lock_t *l_lck;

    if (lck->inited != ERTS_LC_INITITALIZED)
	uninitialized_lock();

    if (lck->id < 0)
	return;

    l_lcks = get_my_locked_locks();

    if (l_lcks) {
	l_lck = l_lcks->required.first;
	if (find_lock(&l_lck, lck))
	    unlock_of_required_lock(l_lcks, lck);
    }

    for (l_lck = l_lcks ? l_lcks->locked.last : NULL; l_lck; l_lck = l_lck->prev) {
	if (l_lck->id == lck->id && l_lck->extra == lck->extra) {
	    if ((l_lck->flags & ERTS_LC_FLG_LO_ALL) != op_flags)
		unlock_op_mismatch(l_lcks, lck, op_flags);
	    if (l_lck->prev)
		l_lck->prev->next = l_lck->next;
	    else
		l_lcks->locked.first = l_lck->next;
	    if (l_lck->next)
		l_lck->next->prev = l_lck->prev;
	    else
		l_lcks->locked.last = l_lck->prev;
	    lc_free((void *) l_lck);
	    return;
	}
    }
    
    unlock_of_not_locked(l_lcks, lck);
}

void erts_lc_might_unlock_flg(erts_lc_lock_t *lck, Uint16 op_flags)
{
    erts_lc_locked_locks_t *l_lcks;
    erts_lc_locked_lock_t *l_lck;

    if (lck->inited != ERTS_LC_INITITALIZED)
	uninitialized_lock();

    if (lck->id < 0)
	return;

    l_lcks = get_my_locked_locks();

    if (l_lcks) {
	l_lck = l_lcks->required.first;
	if (find_lock(&l_lck, lck))
	    unlock_of_required_lock(l_lcks, lck);
    }

    l_lck = l_lcks->locked.first;
    if (!find_lock(&l_lck, lck))
	unlock_of_not_locked(l_lcks, lck);
}

int
erts_lc_trylock_force_busy(erts_lc_lock_t *lck)
{
    return erts_lc_trylock_force_busy_flg(lck, 0);
}

void
erts_lc_trylock(int locked, erts_lc_lock_t *lck)
{
    erts_lc_trylock_flg(locked, lck, 0);
}

void
erts_lc_lock(erts_lc_lock_t *lck)
{
    erts_lc_lock_flg(lck, 0);
}

void
erts_lc_unlock(erts_lc_lock_t *lck)
{
    erts_lc_unlock_flg(lck, 0);
}

void erts_lc_might_unlock(erts_lc_lock_t *lck)
{
    erts_lc_might_unlock_flg(lck, 0);
}

void erts_lc_require_lock(erts_lc_lock_t *lck)
{
    erts_lc_require_lock_flg(lck, 0);
}

void erts_lc_unrequire_lock(erts_lc_lock_t *lck)
{
    erts_lc_unrequire_lock_flg(lck, 0);
}

void
erts_lc_init_lock(erts_lc_lock_t *lck, char *name, Uint16 flags)
{
    lck->id = erts_lc_get_lock_order_id(name);

    lck->extra = (UWord) &lck->extra;
    ASSERT(is_not_immed(lck->extra));
    lck->flags = flags;
    lck->inited = ERTS_LC_INITITALIZED;
}

void
erts_lc_init_lock_x(erts_lc_lock_t *lck, char *name, Uint16 flags, Eterm extra)
{
    lck->id = erts_lc_get_lock_order_id(name);
    lck->extra = extra;
    ASSERT(is_immed(lck->extra));
    lck->flags = flags;
    lck->inited = ERTS_LC_INITITALIZED;
}

void
erts_lc_destroy_lock(erts_lc_lock_t *lck)
{
    if (lck->inited != ERTS_LC_INITITALIZED)
	uninitialized_lock();

    lck->inited = 0;
    lck->id = -1;
    lck->extra = THE_NON_VALUE;
    lck->flags = 0;
}

void
erts_lc_init(void)
{
#ifdef ERTS_LC_STATIC_ALLOC
    int i;
    static erts_lc_free_block_t fbs[ERTS_LC_FB_CHUNK_SIZE];
    for (i = 0; i < ERTS_LC_FB_CHUNK_SIZE - 1; i++) {
#ifdef DEBUG
	memset((void *) &fbs[i], 0xdf, sizeof(erts_lc_free_block_t));
#endif
	fbs[i].next = &fbs[i+1];
    }
#ifdef DEBUG
    memset((void *) &fbs[ERTS_LC_FB_CHUNK_SIZE-1],
	   0xdf, sizeof(erts_lc_free_block_t));
#endif
    fbs[ERTS_LC_FB_CHUNK_SIZE-1].next = NULL;
    free_blocks = &fbs[0]; 
#else /* #ifdef ERTS_LC_STATIC_ALLOC */
    free_blocks = NULL;
#endif /* #ifdef ERTS_LC_STATIC_ALLOC */

    if (ethr_spinlock_init(&free_blocks_lock) != 0)
	lc_abort();

    erts_tsd_key_create(&locks_key);
}

void
erts_lc_late_init(void)
{
    erts_thr_install_exit_handler(thread_exit_handler);
}


/*
 * erts_lc_pll(): print locked locks...
 */
void
erts_lc_pll(void)
{
    print_curr_locks(get_my_locked_locks());
}


#endif /* #ifdef ERTS_ENABLE_LOCK_CHECK */