aboutsummaryrefslogtreecommitdiffstats
path: root/erts/include/internal/ethr_optimized_fallbacks.h
blob: 8c27a9ba5b42d35084838999292143eb4ac44dca (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
/*
 * %CopyrightBegin%
 *
 * Copyright Ericsson AB 2010-2016. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * %CopyrightEnd%
 */

/*
 * Description: Optimized fallbacks used when native ops are missing
 * Author: Rickard Green
 */

#ifndef ETHR_OPTIMIZED_FALLBACKS_H__
#define ETHR_OPTIMIZED_FALLBACKS_H__

#if defined(ETHR_HAVE_NATIVE_SPINLOCKS)

#if defined(ETHR_TRY_INLINE_FUNCS) || defined(ETHR_AUX_IMPL__)

static ETHR_INLINE int
ethr_native_spinlock_destroy(ethr_native_spinlock_t *lock)
{
    return 0;
}

#endif

#elif defined(ETHR_HAVE_PTHREAD_SPIN_LOCK)
/* --- Native spinlocks using pthread spinlocks -------------------------- */
#define ETHR_HAVE_NATIVE_SPINLOCKS 1

#define ETHR_NATIVE_SPINLOCK_IMPL "pthread"

typedef pthread_spinlock_t ethr_native_spinlock_t;

#if defined(ETHR_TRY_INLINE_FUNCS) || defined(ETHR_AUX_IMPL__)

static ETHR_INLINE void
ethr_native_spinlock_init(ethr_native_spinlock_t *lock)
{
    int err = pthread_spin_init((pthread_spinlock_t *) lock, 0);
    if (err)
	ETHR_FATAL_ERROR__(err);
}

static ETHR_INLINE int
ethr_native_spinlock_destroy(ethr_native_spinlock_t *lock)
{
    return pthread_spin_destroy((pthread_spinlock_t *) lock);
}

static ETHR_INLINE void
ethr_native_spin_unlock(ethr_native_spinlock_t *lock)
{
    int err = pthread_spin_unlock((pthread_spinlock_t *) lock);
    if (err)
	ETHR_FATAL_ERROR__(err);
}

static ETHR_INLINE void
ethr_native_spin_lock(ethr_native_spinlock_t *lock)
{
    int err = pthread_spin_lock((pthread_spinlock_t *) lock);
    if (err)
	ETHR_FATAL_ERROR__(err);
}

#endif

#elif defined(ETHR_HAVE_32BIT_NATIVE_ATOMIC_OPS)
/* --- Native spinlocks using native atomics -------------------------------- */
#define ETHR_HAVE_NATIVE_SPINLOCKS 1

#define ETHR_NATIVE_SPINLOCK_IMPL "native-atomics"

typedef ethr_atomic32_t ethr_native_spinlock_t;

#if defined(ETHR_TRY_INLINE_FUNCS) || defined(ETHR_AUX_IMPL__)

#undef ETHR_NSPN_AOP__
#define ETHR_NSPN_AOP__(X) ETHR_INLINE_ATMC32_FUNC_NAME_(ethr_atomic32_ ## X)

static ETHR_INLINE void
ethr_native_spinlock_init(ethr_native_spinlock_t *lock)
{
    ETHR_NSPN_AOP__(init)(lock, 0);
}

static ETHR_INLINE int
ethr_native_spinlock_destroy(ethr_native_spinlock_t *lock)
{
    return ETHR_NSPN_AOP__(read)(lock) == 0 ? 0 : EBUSY;
}

static ETHR_INLINE void
ethr_native_spin_unlock(ethr_native_spinlock_t *lock)
{
    ETHR_ASSERT(ETHR_NSPN_AOP__(read)(lock) == 1);
    ETHR_NSPN_AOP__(set_relb)(lock, 0);
}

static ETHR_INLINE void
ethr_native_spin_lock(ethr_native_spinlock_t *lock)
{
    while (ETHR_NSPN_AOP__(cmpxchg_acqb)(lock, 1, 0) != 0) {
	while (ETHR_NSPN_AOP__(read)(lock) != 0)
	    ETHR_SPIN_BODY;
    }
    ETHR_COMPILER_BARRIER;
}

#undef ETHR_NSPN_AOP__

#endif

#endif


#if defined(ETHR_HAVE_NATIVE_RWSPINLOCKS)

#if defined(ETHR_TRY_INLINE_FUNCS) || defined(ETHR_AUX_IMPL__)

static ETHR_INLINE int
ethr_native_rwlock_destroy(ethr_native_rwlock_t *lock)
{
    return 0;
}

#endif

#elif defined(ETHR_HAVE_32BIT_NATIVE_ATOMIC_OPS)
/* --- Native rwspinlocks using native atomics ------------------------------ */
#define ETHR_HAVE_NATIVE_RWSPINLOCKS 1
#define ETHR_NATIVE_RWSPINLOCK_IMPL "native-atomics"

typedef ethr_atomic32_t ethr_native_rwlock_t;
#  define ETHR_WLOCK_FLAG__ (((ethr_sint32_t) 1) << 30)

#if defined(ETHR_TRY_INLINE_FUNCS) || defined(ETHR_AUX_IMPL__)

#undef ETHR_NRWSPN_AOP__
#define ETHR_NRWSPN_AOP__(X) ETHR_INLINE_ATMC32_FUNC_NAME_(ethr_atomic32_ ## X)

static ETHR_INLINE void
ethr_native_rwlock_init(ethr_native_rwlock_t *lock)
{
    ETHR_NRWSPN_AOP__(init)(lock, 0);
}

static ETHR_INLINE int
ethr_native_rwlock_destroy(ethr_native_rwlock_t *lock)
{
    return ETHR_NRWSPN_AOP__(read)(lock) == 0 ? 0 : EBUSY;
}

static ETHR_INLINE void
ethr_native_read_unlock(ethr_native_rwlock_t *lock)
{
    ETHR_ASSERT(ETHR_NRWSPN_AOP__(read)(lock) >= 0);
    ETHR_NRWSPN_AOP__(dec_relb)(lock);
}

static ETHR_INLINE void
ethr_native_read_lock(ethr_native_rwlock_t *lock)
{
    ethr_sint32_t act, exp = 0;
    while (1) {
	act = ETHR_NRWSPN_AOP__(cmpxchg_acqb)(lock, exp+1, exp);
	if (act == exp)
	    break;
	/* Wait for writer to leave */
	while (act & ETHR_WLOCK_FLAG__) {
	    ETHR_SPIN_BODY;
	    act = ETHR_NRWSPN_AOP__(read)(lock);
	}
	exp = act;
    }
    ETHR_COMPILER_BARRIER;
}

static ETHR_INLINE void
ethr_native_write_unlock(ethr_native_rwlock_t *lock)
{
    ETHR_ASSERT(ETHR_NRWSPN_AOP__(read)(lock) == ETHR_WLOCK_FLAG__);
    ETHR_NRWSPN_AOP__(set_relb)(lock, 0);
}

static ETHR_INLINE void
ethr_native_write_lock(ethr_native_rwlock_t *lock)
{
    ethr_sint32_t act, exp = 0;
    while (1) {
	act = ETHR_NRWSPN_AOP__(cmpxchg_acqb)(lock, exp|ETHR_WLOCK_FLAG__, exp);
	if (act == exp)
	    break;
	/* Wait for writer to leave */
	while (act & ETHR_WLOCK_FLAG__) {
	    ETHR_SPIN_BODY;
	    act = ETHR_NRWSPN_AOP__(read)(lock);
	}
	exp = act;
    }
    act |= ETHR_WLOCK_FLAG__;
    /* Wait for readers to leave */
    while (act != ETHR_WLOCK_FLAG__) {
	ETHR_SPIN_BODY;
	act = ETHR_NRWSPN_AOP__(read_acqb)(lock);
    }
    ETHR_COMPILER_BARRIER;
}

#undef ETHR_NRWSPN_AOP__

#endif

#endif

#endif