aboutsummaryrefslogblamecommitdiffstats
path: root/erts/include/internal/ethread.h
blob: 4e7a38cd5cf13667a677c8df89e40079d283cb95 (plain) (tree)
1
2
3
4
5
6
7
8
9
10
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
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
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468

                   


                                                        




                                                                      
  



                                                                         
  








































































































































































































































































































































































                                                                                                               





                                                                    
























































































































































































































































































































                                                                                  



                                             
          


















                                                                               

          
                                                
































































































































































































































































































































































































































                                                                                





                                                                      

                                































































































































































































































































































































                                                                                     
/*
 * %CopyrightBegin%
 *
 * Copyright Ericsson AB 2004-2010. 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: Thread library for use in the ERTS and other OTP
 *              applications.
 * Author: Rickard Green
 */

#ifndef ETHREAD_H__
#define ETHREAD_H__

#ifndef ETHR_HAVE_ETHREAD_DEFINES
#  include "ethread_header_config.h"
#endif

#include <stdlib.h>
#include "erl_errno.h"

/*
 * Extra memory barrier requirements:
 * - ethr_atomic_or_old() needs to enforce a memory barrier sufficient
 *   for a lock operation.
 * - ethr_atomic_and_old() needs to enforce a memory barrier sufficient
 *   for an unlock operation.
 * - ethr_atomic_cmpxchg() needs to enforce a memory barrier sufficient
 *   for a lock and unlock operation.
 */


#undef ETHR_USE_RWMTX_FALLBACK
#undef ETHR_HAVE_OPTIMIZED_ATOMIC_OPS
#undef ETHR_HAVE_OPTIMIZED_LOCKS

typedef struct {
    long tv_sec;
    long tv_nsec;
} ethr_timeval;

#if defined(DEBUG)
#  undef ETHR_XCHK
#  define  ETHR_XCHK 1
#else
#  ifndef ETHR_XCHK
#    define ETHR_XCHK 0
#  endif
#endif

#undef ETHR_INLINE
#if defined(__GNUC__)
#  define ETHR_INLINE __inline__
#elif defined(__WIN32__)
#  define ETHR_INLINE __forceinline
#endif
#if defined(DEBUG) || !defined(ETHR_INLINE) || ETHR_XCHK \
    || (defined(__GNUC__) && defined(ERTS_MIXED_CYGWIN_VC))
#  undef ETHR_INLINE
#  define ETHR_INLINE 
#  undef ETHR_TRY_INLINE_FUNCS
#endif
#ifdef ETHR_FORCE_INLINE_FUNCS
#  define ETHR_TRY_INLINE_FUNCS
#endif

#if !defined(ETHR_DISABLE_NATIVE_IMPLS) \
    && (defined(PURIFY) || defined(VALGRIND) || defined(ERTS_MIXED_CYGWIN_VC))
#  define ETHR_DISABLE_NATIVE_IMPLS
#endif

#define ETHR_RWMUTEX_INITIALIZED 	0x99999999
#define ETHR_MUTEX_INITIALIZED		0x77777777
#define ETHR_COND_INITIALIZED		0x55555555

#define ETHR_CACHE_LINE_SIZE 64

#ifdef ETHR_INLINE_FUNC_NAME_
#  define ETHR_CUSTOM_INLINE_FUNC_NAME_
#else
#  define ETHR_INLINE_FUNC_NAME_(X) X
#endif

#define ETHR_COMPILER_BARRIER ethr_compiler_barrier()
#ifdef __GNUC__
#  undef ETHR_COMPILER_BARRIER
#  define ETHR_COMPILER_BARRIER __asm__ __volatile__("":::"memory")
#endif

#ifdef DEBUG
#define ETHR_ASSERT(A) \
  ((void) ((A) ? 1 : ethr_assert_failed(__FILE__, __LINE__, #A)))
int ethr_assert_failed(char *f, int l, char *a);
#else
#define ETHR_ASSERT(A) ((void) 1)
#endif

#if defined(ETHR_PTHREADS)
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *\
 * The pthread implementation                                                *
\*                                                                           */

#if defined(__linux__) && !defined(_GNU_SOURCE)
#error "_GNU_SOURCE not defined. Please, compile all files with -D_GNU_SOURCE."
#endif

#if defined(ETHR_HAVE_MIT_PTHREAD_H)
#include <pthread/mit/pthread.h>
#elif defined(ETHR_HAVE_PTHREAD_H)
#include <pthread.h>
#endif

/* Types */

typedef pthread_t ethr_tid;

typedef struct ethr_mutex_ ethr_mutex;
struct ethr_mutex_ {
    pthread_mutex_t pt_mtx;
    int is_rec_mtx;
    ethr_mutex *prev;
    ethr_mutex *next;
#if ETHR_XCHK
    int initialized;
#endif
};

typedef struct ethr_cond_ ethr_cond;
struct ethr_cond_ {
    pthread_cond_t pt_cnd;
#if ETHR_XCHK
    int initialized;
#endif
};

#ifndef ETHR_HAVE_PTHREAD_RWLOCK_INIT
#define ETHR_USE_RWMTX_FALLBACK
#else
typedef struct ethr_rwmutex_ ethr_rwmutex;
struct ethr_rwmutex_ {
    pthread_rwlock_t pt_rwlock;
#if ETHR_XCHK
    int initialized;
#endif
};
#endif

/* Static initializers */
#if ETHR_XCHK
#define ETHR_MUTEX_XCHK_INITER	, ETHR_MUTEX_INITIALIZED
#define ETHR_COND_XCHK_INITER	, ETHR_COND_INITIALIZED
#else
#define ETHR_MUTEX_XCHK_INITER
#define ETHR_COND_XCHK_INITER
#endif

#define ETHR_MUTEX_INITER {PTHREAD_MUTEX_INITIALIZER, 0, NULL, NULL ETHR_MUTEX_XCHK_INITER}
#define ETHR_COND_INITER {PTHREAD_COND_INITIALIZER ETHR_COND_XCHK_INITER}

#if defined(ETHR_HAVE_PTHREAD_MUTEXATTR_SETTYPE) \
    || defined(ETHR_HAVE_PTHREAD_MUTEXATTR_SETKIND_NP)
#  define ETHR_HAVE_ETHR_REC_MUTEX_INIT 1
#  ifdef PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
#    define ETHR_REC_MUTEX_INITER \
            {PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP, 1, NULL, NULL ETHR_MUTEX_XCHK_INITER}
#  endif
#else
#  undef ETHR_HAVE_ETHR_REC_MUTEX_INIT
#endif

#ifndef ETHR_HAVE_PTHREAD_ATFORK
#  define ETHR_NO_FORKSAFETY 1
#endif

typedef pthread_key_t ethr_tsd_key;

#define ETHR_HAVE_ETHR_SIG_FUNCS 1

#ifdef ETHR_TRY_INLINE_FUNCS

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_mutex_trylock)(ethr_mutex *mtx)
{
    return pthread_mutex_trylock(&mtx->pt_mtx);
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_mutex_lock)(ethr_mutex *mtx)
{
    return pthread_mutex_lock(&mtx->pt_mtx);
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_mutex_unlock)(ethr_mutex *mtx)
{
    return pthread_mutex_unlock(&mtx->pt_mtx);
}

#ifdef ETHR_HAVE_PTHREAD_RWLOCK_INIT

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_rwmutex_tryrlock)(ethr_rwmutex *rwmtx)
{
    return pthread_rwlock_tryrdlock(&rwmtx->pt_rwlock);
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_rwmutex_rlock)(ethr_rwmutex *rwmtx)
{
    return pthread_rwlock_rdlock(&rwmtx->pt_rwlock);
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_rwmutex_runlock)(ethr_rwmutex *rwmtx)
{
    return pthread_rwlock_unlock(&rwmtx->pt_rwlock);
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_rwmutex_tryrwlock)(ethr_rwmutex *rwmtx)
{
    return pthread_rwlock_trywrlock(&rwmtx->pt_rwlock);
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_rwmutex_rwlock)(ethr_rwmutex *rwmtx)
{
    return pthread_rwlock_wrlock(&rwmtx->pt_rwlock);
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_rwmutex_rwunlock)(ethr_rwmutex *rwmtx)
{
    return pthread_rwlock_unlock(&rwmtx->pt_rwlock);
}

#endif /* ETHR_HAVE_PTHREAD_RWLOCK_INIT */

#endif /* ETHR_TRY_INLINE_FUNCS */

#elif defined(ETHR_WIN32_THREADS)
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *\
 * The native win32 threads implementation                                   *
\*                                                                           */

#if !defined(_WIN32_WINNT)
#error "_WIN32_WINNT not defined. Please, compile all files with -D_WIN32_WINNT=0x0403"
#elif _WIN32_WINNT < 0x0403
#error "_WIN32_WINNT defined to a value less than 0x0403. Please, compile all files with -D_WIN32_WINNT=0x0403"
#endif

#ifdef WIN32_LEAN_AND_MEAN
#  define ETHR_WIN32_LEAN_AND_MEAN_ALREADY_DEFINED
#else
#  define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifndef ETHR_WIN32_LEAN_AND_MEAN_ALREADY_DEFINED
#  undef WIN32_LEAN_AND_MEAN
#endif

/* Types */
typedef long ethr_tid; /* thread id type */
typedef struct {
    volatile int initialized;
    CRITICAL_SECTION cs;
#if ETHR_XCHK
    int is_rec_mtx;
#endif
} ethr_mutex;

typedef struct cnd_wait_event__ cnd_wait_event_;

typedef struct {
    volatile int initialized;
    CRITICAL_SECTION cs;
    cnd_wait_event_ *queue;
    cnd_wait_event_ *queue_end;
} ethr_cond;

#define ETHR_USE_RWMTX_FALLBACK

/* Static initializers */

#define ETHR_MUTEX_INITER {0}
#define ETHR_COND_INITER {0}

#define ETHR_REC_MUTEX_INITER ETHR_MUTEX_INITER

#define ETHR_HAVE_ETHR_REC_MUTEX_INIT 1

typedef DWORD ethr_tsd_key;

#undef ETHR_HAVE_ETHR_SIG_FUNCS

#ifdef ETHR_TRY_INLINE_FUNCS
int ethr_fake_static_mutex_init(ethr_mutex *mtx);

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_mutex_trylock)(ethr_mutex *mtx)
{
    if (!mtx->initialized) {
	int res = ethr_fake_static_mutex_init(mtx);
	if (res != 0)
	    return res;
    }
    return TryEnterCriticalSection(&mtx->cs) ? 0 : EBUSY;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_mutex_lock)(ethr_mutex *mtx)
{
    if (!mtx->initialized) {
	int res = ethr_fake_static_mutex_init(mtx);
	if (res != 0)
	    return res;
    }
    EnterCriticalSection(&mtx->cs);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_mutex_unlock)(ethr_mutex *mtx)
{
    LeaveCriticalSection(&mtx->cs);
    return 0;
}

#endif /* #ifdef ETHR_TRY_INLINE_FUNCS */

#ifdef ERTS_MIXED_CYGWIN_VC

/* atomics */

#ifdef _MSC_VER
#  if _MSC_VER < 1300
#    define ETHR_IMMED_ATOMIC_SET_GET_SAFE__ 0 /* Dont trust really old compilers */
#  else
#    if defined(_M_IX86)
#      define ETHR_IMMED_ATOMIC_SET_GET_SAFE__ 1
#    else /* I.e. IA64 */
#      if _MSC_VER >= 1400 
#        define ETHR_IMMED_ATOMIC_SET_GET_SAFE__ 1
#      else
#        define ETHR_IMMED_ATOMIC_SET_GET_SAFE__ 0
#      endif
#    endif
#  endif
#  if _MSC_VER >= 1400
#    include <intrin.h>
#    undef ETHR_COMPILER_BARRIER
#    define ETHR_COMPILER_BARRIER _ReadWriteBarrier()
#  endif
#pragma intrinsic(_ReadWriteBarrier)
#pragma intrinsic(_InterlockedAnd)
#pragma intrinsic(_InterlockedOr)
#else
#    define ETHR_IMMED_ATOMIC_SET_GET_SAFE__ 0 
#endif

#define ETHR_HAVE_OPTIMIZED_ATOMIC_OPS 1
#define ETHR_HAVE_OPTIMIZED_LOCKS 1

#define ETHR_MEMORY_BARRIER \
do { \
    volatile LONG x___ = 0; \
    (void) _InterlockedCompareExchange(&x___, (LONG) 1, (LONG) 0); \
} while (0)

typedef struct {
    volatile LONG value;
} ethr_atomic_t;

typedef struct {
    volatile LONG locked;
} ethr_spinlock_t;

typedef struct {
    volatile LONG counter;
} ethr_rwlock_t;
#define ETHR_WLOCK_FLAG__ (((LONG) 1) << 30)

#ifdef ETHR_TRY_INLINE_FUNCS

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_init)(ethr_atomic_t *var, long i)
{
#if ETHR_IMMED_ATOMIC_SET_GET_SAFE__
    var->value = (LONG) i;
#else
    (void) InterlockedExchange(&var->value, (LONG) i);
#endif
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_set)(ethr_atomic_t *var, long i)
{
#if ETHR_IMMED_ATOMIC_SET_GET_SAFE__
    var->value = (LONG) i;
#else
    (void) InterlockedExchange(&var->value, (LONG) i);
#endif
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_read)(ethr_atomic_t *var, long *i)
{
#if ETHR_IMMED_ATOMIC_SET_GET_SAFE__
    *i = var->value;
#else
    *i = InterlockedExchangeAdd(&var->value, (LONG) 0);
#endif
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_add)(ethr_atomic_t *var, long incr)
{
    (void) InterlockedExchangeAdd(&var->value, (LONG) incr);
    return 0;
}   
    
static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_addtest)(ethr_atomic_t *var,
					    long i,
					    long *testp)
{
    *testp = InterlockedExchangeAdd(&var->value, (LONG) i);
    *testp += i;
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_inc)(ethr_atomic_t *var)
{
    (void) InterlockedIncrement(&var->value);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_dec)(ethr_atomic_t *var)
{
    (void) InterlockedDecrement(&var->value);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_inctest)(ethr_atomic_t *var, long *testp)
{
    *testp = (long) InterlockedIncrement(&var->value);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_dectest)(ethr_atomic_t *var, long *testp)
{
    *testp = (long) InterlockedDecrement(&var->value);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_and_old)(ethr_atomic_t *var,
					    long mask,
					    long *old)
{
    /*
     * See "Extra memory barrier requirements" note at the top
     * of the file.
     *
     * According to msdn _InterlockedAnd() provides a full
     * memory barrier.
     */
    *old = (long) _InterlockedAnd(&var->value, mask);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_or_old)(ethr_atomic_t *var,
					   long mask,
					   long *old)
{
    /*
     * See "Extra memory barrier requirements" note at the top
     * of the file.
     *
     * According to msdn _InterlockedOr() provides a full
     * memory barrier.
     */
    *old = (long) _InterlockedOr(&var->value, mask);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_cmpxchg)(ethr_atomic_t *var,
					    long new,
                                            long expected,
					    long *old)
{
    /*
     * See "Extra memory barrier requirements" note at the top
     * of the file.
     *
     * According to msdn _InterlockedCompareExchange() provides a full
     * memory barrier.
     */
    *old = _InterlockedCompareExchange(&var->value, (LONG) new, (LONG) expected);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_xchg)(ethr_atomic_t *var,
					 long new,
					 long *old)
{
    *old = (long) InterlockedExchange(&var->value, (LONG) new);
    return 0;
}

/*
 * According to msdn InterlockedExchange() provides a full
 * memory barrier. 
 */

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_spinlock_init)(ethr_spinlock_t *lock)
{
#if ETHR_IMMED_ATOMIC_SET_GET_SAFE__
    lock->locked = (LONG) 0;
#else
    (void) InterlockedExchange(&lock->locked, (LONG) 0);
#endif
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_spinlock_destroy)(ethr_spinlock_t *lock)
{
    return 0;
}


static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_spin_unlock)(ethr_spinlock_t *lock)
{
    ETHR_COMPILER_BARRIER;
    {
#ifdef DEBUG
	LONG old =
#endif
	    InterlockedExchange(&lock->locked, (LONG) 0);
#ifdef DEBUG
	ETHR_ASSERT(old == 1);
#endif
    }
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_spin_lock)(ethr_spinlock_t *lock)
{
    LONG old;
    do {
	old = InterlockedExchange(&lock->locked, (LONG) 1);
    } while (old != (LONG) 0);
    ETHR_COMPILER_BARRIER;
    return 0;
}

/*
 * According to msdn InterlockedIncrement, InterlockedDecrement,
 * and InterlockedExchangeAdd(), _InterlockedAnd, and _InterlockedOr
 * provides full memory barriers.
 */
static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_rwlock_init)(ethr_rwlock_t *lock)
{
#if ETHR_IMMED_ATOMIC_SET_GET_SAFE__
    lock->counter = (LONG) 0;
#else
    (void) InterlockedExchange(&lock->counter, (LONG) 0);
#endif
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_rwlock_destroy)(ethr_rwlock_t *lock)
{
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_read_unlock)(ethr_rwlock_t *lock)
{
    ETHR_COMPILER_BARRIER;
    {
#ifdef DEBUG
	LONG old =
#endif
	    InterlockedDecrement(&lock->counter);
	ETHR_ASSERT(old != 0);
    }
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_read_lock)(ethr_rwlock_t *lock)
{
    while (1) {
	LONG old = InterlockedIncrement(&lock->counter);
	if ((old & ETHR_WLOCK_FLAG__) == 0)
	    break; /* Got read lock */
	/* Restore and wait for writers to unlock */
	old = InterlockedDecrement(&lock->counter);
	while (old & ETHR_WLOCK_FLAG__) {
#if ETHR_IMMED_ATOMIC_SET_GET_SAFE__
	    old = lock->counter;
#else
	    old = InterlockedExchangeAdd(&lock->counter, (LONG) 0);
#endif
	}
    }
    ETHR_COMPILER_BARRIER;
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_write_unlock)(ethr_rwlock_t *lock)
{
    ETHR_COMPILER_BARRIER;
    {
#ifdef DEBUG
	LONG old =
#endif
	    _InterlockedAnd(&lock->counter, ~ETHR_WLOCK_FLAG__);
	ETHR_ASSERT(old & ETHR_WLOCK_FLAG__);
    }
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_write_lock)(ethr_rwlock_t *lock)
{
    LONG old;
    do {
	old = _InterlockedOr(&lock->counter, ETHR_WLOCK_FLAG__);
    } while (old & ETHR_WLOCK_FLAG__);
    /* We got the write part of the lock; wait for readers to unlock */
    while ((old & ~ETHR_WLOCK_FLAG__) != 0) {
#if ETHR_IMMED_ATOMIC_SET_GET_SAFE__
	old = lock->counter;
#else
	old = InterlockedExchangeAdd(&lock->counter, (LONG) 0);
#endif
	ETHR_ASSERT(old & ETHR_WLOCK_FLAG__);
    }
    ETHR_COMPILER_BARRIER;
    return 0;
}

#endif /* #ifdef ETHR_TRY_INLINE_FUNCS */

#endif /* #ifdef ERTS_MIXED_CYGWIN_VC */

#else /* No supported thread lib found */

#ifdef ETHR_NO_SUPP_THR_LIB_NOT_FATAL
#define ETHR_NO_THREAD_LIB
#else
#error "No supported thread lib found"
#endif

#endif

/* __builtin_expect() is needed by both native atomics code 
 * and the fallback code */
#if !defined(__GNUC__) || (__GNUC__ < 2) || (__GNUC__ == 2 && __GNUC_MINOR__ < 96)
#define __builtin_expect(X, Y) (X)
#endif

/* For CPU-optimised atomics, spinlocks, and rwlocks. */
#if !defined(ETHR_DISABLE_NATIVE_IMPLS)
#  if defined(__GNUC__)
#    if defined(ETHR_PREFER_GCC_NATIVE_IMPLS)
#      include "gcc/ethread.h"
#    endif
#    ifndef ETHR_HAVE_NATIVE_ATOMICS
#      if ETHR_SIZEOF_PTR == 4
#        if defined(__i386__)
#          include "i386/ethread.h"
#        elif (defined(__powerpc__)||defined(__ppc__))&&!defined(__powerpc64__)
#          include "ppc32/ethread.h"
#        elif defined(__sparc__)
#          include "sparc32/ethread.h"
#        elif defined(__tile__)
#          include "tile/ethread.h"
#        endif
#      elif ETHR_SIZEOF_PTR == 8
#        if defined(__x86_64__)
#          include "x86_64/ethread.h"
#        elif defined(__sparc__) && defined(__arch64__)
#          include "sparc64/ethread.h"
#        endif
#      endif
#      include "gcc/ethread.h"
#    endif
#  endif
#endif /* !defined(ETHR_DISABLE_NATIVE_IMPLS) */

#ifdef ETHR_HAVE_OPTIMIZED_ATOMIC_OPS
#  undef ETHR_HAVE_NATIVE_ATOMICS
#endif
#ifdef ETHR_HAVE_OPTIMIZED_LOCKS
#  undef ETHR_HAVE_NATIVE_LOCKS
#endif

#ifdef ETHR_HAVE_NATIVE_ATOMICS
#define ETHR_HAVE_OPTIMIZED_ATOMIC_OPS 1
#endif
#ifdef ETHR_HAVE_NATIVE_LOCKS
#define ETHR_HAVE_OPTIMIZED_LOCKS 1
#endif

typedef struct {
    unsigned open;
    ethr_mutex mtx;
    ethr_cond cnd;
} ethr_gate;

#ifdef ETHR_HAVE_NATIVE_ATOMICS
/*
 * Map ethread native atomics to ethread API atomics.
 */
typedef ethr_native_atomic_t ethr_atomic_t;
#endif

#ifdef ETHR_HAVE_NATIVE_LOCKS
/*
 * Map ethread native spinlocks to ethread API spinlocks.
 */
typedef ethr_native_spinlock_t ethr_spinlock_t;
/*
 * Map ethread native rwlocks to ethread API rwlocks.
 */
typedef ethr_native_rwlock_t ethr_rwlock_t;
#endif

#ifdef ETHR_USE_RWMTX_FALLBACK
typedef struct {
    ethr_mutex mtx;
    ethr_cond rcnd;
    ethr_cond wcnd;
    unsigned readers;
    unsigned waiting_readers;
    unsigned waiting_writers;
#if ETHR_XCHK
    int initialized;
#endif
} ethr_rwmutex;
#endif

#ifndef ETHR_HAVE_OPTIMIZED_ATOMIC_OPS
typedef long ethr_atomic_t;
#endif

#ifndef ETHR_HAVE_OPTIMIZED_LOCKS

#if defined(ETHR_WIN32_THREADS)
typedef struct {
    CRITICAL_SECTION cs;
} ethr_spinlock_t;
typedef struct {
    CRITICAL_SECTION cs;
    unsigned counter;
} ethr_rwlock_t;

int ethr_do_spinlock_init(ethr_spinlock_t *lock);
int ethr_do_rwlock_init(ethr_rwlock_t *lock);

#define ETHR_RWLOCK_WRITERS (((unsigned) 1) << 31)

#elif defined(ETHR_HAVE_PTHREAD_SPIN_LOCK)
typedef struct {
    pthread_spinlock_t spnlck;
} ethr_spinlock_t;
typedef struct {
    pthread_spinlock_t spnlck;
    unsigned counter;
} ethr_rwlock_t;
#define ETHR_RWLOCK_WRITERS (((unsigned) 1) << 31)

#else /* ethr mutex/rwmutex */

typedef struct {
    ethr_mutex mtx;
} ethr_spinlock_t;

typedef struct {
    ethr_rwmutex rwmtx;
} ethr_rwlock_t;

#endif /* end mutex/rwmutex */
#endif /* ETHR_HAVE_OPTIMIZED_LOCKS */

typedef struct {
    void *(*alloc)(size_t);
    void *(*realloc)(void *, size_t);
    void (*free)(void *);
    void *(*thread_create_prepare_func)(void);
    void (*thread_create_parent_func)(void *);
    void (*thread_create_child_func)(void *);
} ethr_init_data;

#define ETHR_INIT_DATA_DEFAULT_INITER {malloc, realloc, free, NULL, NULL, NULL}

typedef struct {
    int detached;			/* boolean (default false) */
    int suggested_stack_size;		/* kilo words (default sys dependent) */
} ethr_thr_opts;

#define ETHR_THR_OPTS_DEFAULT_INITER {0, -1}

#if defined(ETHR_CUSTOM_INLINE_FUNC_NAME_) || !defined(ETHR_TRY_INLINE_FUNCS)
#  define ETHR_NEED_MTX_PROTOTYPES__
#  define ETHR_NEED_RWMTX_PROTOTYPES__
#  define ETHR_NEED_SPINLOCK_PROTOTYPES__
#  define ETHR_NEED_ATOMIC_PROTOTYPES__
#endif

#if !defined(ETHR_NEED_RWMTX_PROTOTYPES__) && defined(ETHR_USE_RWMTX_FALLBACK)
#  define ETHR_NEED_RWMTX_PROTOTYPES__
#endif

int ethr_init(ethr_init_data *);
int ethr_install_exit_handler(void (*funcp)(void));
int ethr_thr_create(ethr_tid *, void * (*)(void *), void *, ethr_thr_opts *);
int ethr_thr_join(ethr_tid, void **);
int ethr_thr_detach(ethr_tid);
void ethr_thr_exit(void *);
ethr_tid ethr_self(void);
int ethr_equal_tids(ethr_tid, ethr_tid);
int ethr_mutex_init(ethr_mutex *);
#ifdef ETHR_HAVE_ETHR_REC_MUTEX_INIT
int ethr_rec_mutex_init(ethr_mutex *);
#endif
int ethr_mutex_destroy(ethr_mutex *);
int ethr_mutex_set_forksafe(ethr_mutex *);
int ethr_mutex_unset_forksafe(ethr_mutex *);
#ifdef ETHR_NEED_MTX_PROTOTYPES__
int ethr_mutex_trylock(ethr_mutex *);
int ethr_mutex_lock(ethr_mutex *);
int ethr_mutex_unlock(ethr_mutex *);
#endif
int ethr_cond_init(ethr_cond *);
int ethr_cond_destroy(ethr_cond *);
int ethr_cond_signal(ethr_cond *);
int ethr_cond_broadcast(ethr_cond *);
int ethr_cond_wait(ethr_cond *, ethr_mutex *);
int ethr_cond_timedwait(ethr_cond *, ethr_mutex *, ethr_timeval *);

int ethr_rwmutex_init(ethr_rwmutex *);
int ethr_rwmutex_destroy(ethr_rwmutex *);
#ifdef ETHR_NEED_RWMTX_PROTOTYPES__
int ethr_rwmutex_tryrlock(ethr_rwmutex *);
int ethr_rwmutex_rlock(ethr_rwmutex *);
int ethr_rwmutex_runlock(ethr_rwmutex *);
int ethr_rwmutex_tryrwlock(ethr_rwmutex *);
int ethr_rwmutex_rwlock(ethr_rwmutex *);
int ethr_rwmutex_rwunlock(ethr_rwmutex *);
#endif

#ifdef ETHR_NEED_ATOMIC_PROTOTYPES__
int ethr_atomic_init(ethr_atomic_t *, long);
int ethr_atomic_set(ethr_atomic_t *, long);
int ethr_atomic_read(ethr_atomic_t *, long *);
int ethr_atomic_inctest(ethr_atomic_t *, long *);
int ethr_atomic_dectest(ethr_atomic_t *, long *);
int ethr_atomic_inc(ethr_atomic_t *);
int ethr_atomic_dec(ethr_atomic_t *);
int ethr_atomic_addtest(ethr_atomic_t *, long, long *);
int ethr_atomic_add(ethr_atomic_t *, long);
int ethr_atomic_and_old(ethr_atomic_t *, long, long *);
int ethr_atomic_or_old(ethr_atomic_t *, long, long *);
int ethr_atomic_xchg(ethr_atomic_t *, long, long *);
int ethr_atomic_cmpxchg(ethr_atomic_t *, long, long, long *);
#endif

#ifdef ETHR_NEED_SPINLOCK_PROTOTYPES__
int ethr_spinlock_init(ethr_spinlock_t *);
int ethr_spinlock_destroy(ethr_spinlock_t *);
int ethr_spin_unlock(ethr_spinlock_t *);
int ethr_spin_lock(ethr_spinlock_t *);

int ethr_rwlock_init(ethr_rwlock_t *);
int ethr_rwlock_destroy(ethr_rwlock_t *);
int ethr_read_unlock(ethr_rwlock_t *);
int ethr_read_lock(ethr_rwlock_t *);
int ethr_write_unlock(ethr_rwlock_t *);
int ethr_write_lock(ethr_rwlock_t *);
#endif

int ethr_time_now(ethr_timeval *);
int ethr_tsd_key_create(ethr_tsd_key *);
int ethr_tsd_key_delete(ethr_tsd_key);
int ethr_tsd_set(ethr_tsd_key, void *);
void *ethr_tsd_get(ethr_tsd_key);

int ethr_gate_init(ethr_gate *);
int ethr_gate_destroy(ethr_gate *);
int ethr_gate_close(ethr_gate *);
int ethr_gate_let_through(ethr_gate *, unsigned);
int ethr_gate_wait(ethr_gate *);
int ethr_gate_swait(ethr_gate *, int);

#ifdef ETHR_HAVE_ETHR_SIG_FUNCS
#include <signal.h>
int ethr_sigmask(int how, const sigset_t *set, sigset_t *oset);
int ethr_sigwait(const sigset_t *set, int *sig);
#endif

void ethr_compiler_barrier(void);

#ifdef ETHR_TRY_INLINE_FUNCS

#ifdef ETHR_HAVE_NATIVE_ATOMICS

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_init)(ethr_atomic_t *var, long i)
{
    ethr_native_atomic_init(var, i);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_set)(ethr_atomic_t *var, long i)
{
    ethr_native_atomic_set(var, i);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_read)(ethr_atomic_t *var, long *i)
{
    *i = ethr_native_atomic_read(var);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_add)(ethr_atomic_t *var, long incr)
{
    ethr_native_atomic_add(var, incr);
    return 0;
}   
    
static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_addtest)(ethr_atomic_t *var,
					    long i,
					    long *testp)
{
    *testp = ethr_native_atomic_add_return(var, i);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_inc)(ethr_atomic_t *var)
{
    ethr_native_atomic_inc(var);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_dec)(ethr_atomic_t *var)
{
    ethr_native_atomic_dec(var);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_inctest)(ethr_atomic_t *var, long *testp)
{
    *testp = ethr_native_atomic_inc_return(var);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_dectest)(ethr_atomic_t *var, long *testp)
{
    *testp = ethr_native_atomic_dec_return(var);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_and_old)(ethr_atomic_t *var,
					    long mask,
					    long *old)
{
    /*
     * See "Extra memory barrier requirements" note at the top
     * of the file.
     */
    *old = ethr_native_atomic_and_retold(var, mask);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_or_old)(ethr_atomic_t *var,
					   long mask,
					   long *old)
{
    /*
     * See "Extra memory barrier requirements" note at the top
     * of the file.
     */
    *old = ethr_native_atomic_or_retold(var, mask);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_xchg)(ethr_atomic_t *var,
					 long new,
					 long *old)
{
    *old = ethr_native_atomic_xchg(var, new);
    return 0;
}   

/*
 * If *var == *old, replace *old with new, else do nothing.
 * In any case return the original value of *var in *old.
 */
static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_cmpxchg)(ethr_atomic_t *var,
					    long new,
                                            long expected,
					    long *old)
{
    /*
     * See "Extra memory barrier requirements" note at the top
     * of the file.
     */
    *old = ethr_native_atomic_cmpxchg(var, new, expected);
    return 0;
}

#endif /* ETHR_HAVE_NATIVE_ATOMICS */

#ifdef ETHR_HAVE_NATIVE_LOCKS

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_spinlock_init)(ethr_spinlock_t *lock)
{
    ethr_native_spinlock_init(lock);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_spinlock_destroy)(ethr_spinlock_t *lock)
{
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_spin_unlock)(ethr_spinlock_t *lock)
{
    ethr_native_spin_unlock(lock);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_spin_lock)(ethr_spinlock_t *lock)
{
    ethr_native_spin_lock(lock);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_rwlock_init)(ethr_rwlock_t *lock)
{
    ethr_native_rwlock_init(lock);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_rwlock_destroy)(ethr_rwlock_t *lock)
{
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_read_unlock)(ethr_rwlock_t *lock)
{
    ethr_native_read_unlock(lock);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_read_lock)(ethr_rwlock_t *lock)
{
    ethr_native_read_lock(lock);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_write_unlock)(ethr_rwlock_t *lock)
{
    ethr_native_write_unlock(lock);
    return 0;
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_write_lock)(ethr_rwlock_t *lock)
{
    ethr_native_write_lock(lock);
    return 0;
}

#endif /* ETHR_HAVE_NATIVE_LOCKS */

#endif /* ETHR_TRY_INLINE_FUNCS */

/*
 * Fallbacks for atomics used in absence of optimized implementation.
 */
#ifndef ETHR_HAVE_OPTIMIZED_ATOMIC_OPS

/*
 * ETHR_MEMORY_BARRIER orders between locked and atomic accesses only,
 * i.e. when this atomic fallback is used a noop is sufficient.
 */
#define ETHR_MEMORY_BARRIER

#define ETHR_ATOMIC_ADDR_BITS 10
#define ETHR_ATOMIC_ADDR_SHIFT 6

typedef struct {
    union {
#if defined(ETHR_HAVE_PTHREAD_SPIN_LOCK)
	pthread_spinlock_t spnlck;
#else
	ethr_mutex mtx;
#endif
	char buf[ETHR_CACHE_LINE_SIZE];
    } u;
} ethr_atomic_protection_t;

extern ethr_atomic_protection_t ethr_atomic_protection__[1 << ETHR_ATOMIC_ADDR_BITS];


#if defined(ETHR_HAVE_PTHREAD_SPIN_LOCK)

#define ETHR_ATOMIC_PTR2LCK__(PTR) \
(&ethr_atomic_protection__[((((unsigned long) (PTR)) >> ETHR_ATOMIC_ADDR_SHIFT) \
			& ((1 << ETHR_ATOMIC_ADDR_BITS) - 1))].u.spnlck)


#define ETHR_ATOMIC_OP_FALLBACK_IMPL__(AP, EXPS)			\
do {									\
    pthread_spinlock_t *slp__ = ETHR_ATOMIC_PTR2LCK__((AP));		\
    int res__ = pthread_spin_lock(slp__);				\
    if (res__ != 0)							\
	return res__;							\
    { EXPS; }								\
    return pthread_spin_unlock(slp__);					\
} while (0)

#else /* ethread mutex */

#define ETHR_ATOMIC_PTR2LCK__(PTR) \
(&ethr_atomic_protection__[((((unsigned long) (PTR)) >> ETHR_ATOMIC_ADDR_SHIFT) \
		     & ((1 << ETHR_ATOMIC_ADDR_BITS) - 1))].u.mtx)

#define ETHR_ATOMIC_OP_FALLBACK_IMPL__(AP, EXPS)			\
do {									\
    ethr_mutex *mtxp__ = ETHR_ATOMIC_PTR2LCK__((AP));			\
    int res__ = ETHR_INLINE_FUNC_NAME_(ethr_mutex_lock)(mtxp__);	\
    if (res__ != 0)							\
	return res__;							\
    { EXPS; }								\
    return ETHR_INLINE_FUNC_NAME_(ethr_mutex_unlock)(mtxp__);		\
} while (0)

#endif /* end ethread mutex */

#ifdef ETHR_TRY_INLINE_FUNCS

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_init)(ethr_atomic_t *var, long i)
{
    ETHR_ATOMIC_OP_FALLBACK_IMPL__(var, *var = (ethr_atomic_t) i);
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_set)(ethr_atomic_t *var, long i)
{
    ETHR_ATOMIC_OP_FALLBACK_IMPL__(var, *var = (ethr_atomic_t) i);
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_read)(ethr_atomic_t *var, long *i)
{
    ETHR_ATOMIC_OP_FALLBACK_IMPL__(var, *i = (long) *var);
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_inctest)(ethr_atomic_t *incp, long *testp)
{
    ETHR_ATOMIC_OP_FALLBACK_IMPL__(incp, *testp = (long) ++(*incp));
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_dectest)(ethr_atomic_t *decp, long *testp)
{
    ETHR_ATOMIC_OP_FALLBACK_IMPL__(decp, *testp = (long) --(*decp));
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_add)(ethr_atomic_t *var, long incr)
{
    ETHR_ATOMIC_OP_FALLBACK_IMPL__(var, *var += incr);
}   
    
static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_addtest)(ethr_atomic_t *incp,
					    long i,
					    long *testp)
{
    ETHR_ATOMIC_OP_FALLBACK_IMPL__(incp, *incp += i; *testp = *incp);
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_inc)(ethr_atomic_t *incp)
{
    ETHR_ATOMIC_OP_FALLBACK_IMPL__(incp, ++(*incp));
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_dec)(ethr_atomic_t *decp)
{
    ETHR_ATOMIC_OP_FALLBACK_IMPL__(decp, --(*decp));
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_and_old)(ethr_atomic_t *var,
					    long mask,
					    long *old)
{
    /*
     * See "Extra memory barrier requirements" note at the top
     * of the file.
     */
    ETHR_ATOMIC_OP_FALLBACK_IMPL__(var, *old = *var; *var &= mask);
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_or_old)(ethr_atomic_t *var,
					   long mask,
					   long *old)
{
    /*
     * See "Extra memory barrier requirements" note at the top
     * of the file.
     */
    ETHR_ATOMIC_OP_FALLBACK_IMPL__(var, *old = *var; *var |= mask);
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_xchg)(ethr_atomic_t *var,
					 long new,
					 long *old)
{
    ETHR_ATOMIC_OP_FALLBACK_IMPL__(var, *old = *var; *var = new);
}   

/*
 * If *var == *old, replace *old with new, else do nothing.
 * In any case return the original value of *var in *old.
 */
static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_atomic_cmpxchg)(ethr_atomic_t *var,
					    long new,
                                            long expected,
					    long *old)
{
    /*
     * See "Extra memory barrier requirements" note at the top
     * of the file.
     */
    ETHR_ATOMIC_OP_FALLBACK_IMPL__(
      var,
      long old_val = *var;
      *old = old_val;
      if (__builtin_expect(old_val == expected, 1))
          *var = new;
      );
    return 0;
}

#endif /* #ifdef ETHR_TRY_INLINE_FUNCS */
#endif /* #ifndef ETHR_HAVE_OPTIMIZED_ATOMIC_OPS */

/*
 * Fallbacks for spin locks, and rw spin locks used in absence of
 * optimized implementation.
 */
#ifndef ETHR_HAVE_OPTIMIZED_LOCKS

#ifdef ETHR_TRY_INLINE_FUNCS

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_spinlock_init)(ethr_spinlock_t *lock)
{
#if defined(ETHR_HAVE_PTHREAD_SPIN_LOCK)
    return pthread_spin_init(&lock->spnlck, 0);
#else
    return ethr_mutex_init(&lock->mtx);
#endif
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_spinlock_destroy)(ethr_spinlock_t *lock)
{
#if defined(ETHR_HAVE_PTHREAD_SPIN_LOCK)
    return pthread_spin_destroy(&lock->spnlck);
#else
    return ethr_mutex_destroy(&lock->mtx);
#endif
}


static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_spin_unlock)(ethr_spinlock_t *lock)
{
#if defined(ETHR_HAVE_PTHREAD_SPIN_LOCK)
    return pthread_spin_unlock(&lock->spnlck);
#else
    return ETHR_INLINE_FUNC_NAME_(ethr_mutex_unlock)(&lock->mtx);
#endif
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_spin_lock)(ethr_spinlock_t *lock)
{
#if defined(ETHR_HAVE_PTHREAD_SPIN_LOCK)
    return pthread_spin_lock(&lock->spnlck);
#else
    return ETHR_INLINE_FUNC_NAME_(ethr_mutex_lock)(&lock->mtx);
#endif
}

#ifdef ETHR_USE_RWMTX_FALLBACK
#define ETHR_RWLOCK_RWMTX_FALLBACK_NAME_(X) X
#else
#define ETHR_RWLOCK_RWMTX_FALLBACK_NAME_(X) ETHR_INLINE_FUNC_NAME_(X)
#endif

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_rwlock_init)(ethr_rwlock_t *lock)
{
#if defined(ETHR_HAVE_PTHREAD_SPIN_LOCK)
    lock->counter = 0;
    return pthread_spin_init(&lock->spnlck, 0);
#else
    return ethr_rwmutex_init(&lock->rwmtx);
#endif
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_rwlock_destroy)(ethr_rwlock_t *lock)
{
#if defined(ETHR_HAVE_PTHREAD_SPIN_LOCK)
    return pthread_spin_destroy(&lock->spnlck);
#else
    return ethr_rwmutex_destroy(&lock->rwmtx);
#endif
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_read_unlock)(ethr_rwlock_t *lock)
{
#if defined(ETHR_HAVE_PTHREAD_SPIN_LOCK)
    int res = pthread_spin_lock(&lock->spnlck);
    if (res != 0)
	return res;
    lock->counter--;
    return pthread_spin_unlock(&lock->spnlck);
#else
    return ETHR_RWLOCK_RWMTX_FALLBACK_NAME_(ethr_rwmutex_runlock)(&lock->rwmtx);
#endif
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_read_lock)(ethr_rwlock_t *lock)
{
#if defined(ETHR_HAVE_PTHREAD_SPIN_LOCK)
    int locked = 0;
    do {
	int res = pthread_spin_lock(&lock->spnlck);
	if (res != 0)
	    return res;
	if ((lock->counter & ETHR_RWLOCK_WRITERS) == 0) {
	    lock->counter++;
	    locked = 1;
	}
	res = pthread_spin_unlock(&lock->spnlck);
	if (res != 0)
	    return res;
    } while (!locked);
    return 0;
#else
    return ETHR_RWLOCK_RWMTX_FALLBACK_NAME_(ethr_rwmutex_rlock)(&lock->rwmtx);
#endif
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_write_unlock)(ethr_rwlock_t *lock)
{
#if defined(ETHR_HAVE_PTHREAD_SPIN_LOCK)
    lock->counter = 0;
    return pthread_spin_unlock(&lock->spnlck);
#else
    return ETHR_RWLOCK_RWMTX_FALLBACK_NAME_(ethr_rwmutex_rwunlock)(&lock->rwmtx);
#endif
}

static ETHR_INLINE int
ETHR_INLINE_FUNC_NAME_(ethr_write_lock)(ethr_rwlock_t *lock)
{
#if defined(ETHR_HAVE_PTHREAD_SPIN_LOCK)
    while (1) {
	int res = pthread_spin_lock(&lock->spnlck);
	if (res != 0)
	    return res;
	lock->counter |= ETHR_RWLOCK_WRITERS;
	if (lock->counter == ETHR_RWLOCK_WRITERS)
	    return 0;
	res = pthread_spin_unlock(&lock->spnlck);
	if (res != 0)
	    return res;
    }
#else
    return ETHR_RWLOCK_RWMTX_FALLBACK_NAME_(ethr_rwmutex_rwlock)(&lock->rwmtx);
#endif
}

#endif /* #ifdef ETHR_TRY_INLINE_FUNCS */

#endif /* ETHR_HAVE_OPTIMIZED_LOCKS */

#if defined(ETHR_HAVE_OPTIMIZED_LOCKS) || defined(ETHR_HAVE_PTHREAD_SPIN_LOCK)
# define ETHR_HAVE_OPTIMIZED_SPINLOCK
#endif

#endif /* #ifndef ETHREAD_H__ */