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
|
/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 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: Native atomics ethread support using libatomic_ops
* Author: Rickard Green
*/
#ifndef ETHR_LIBATOMIC_OPS_ATOMIC_H__
#define ETHR_LIBATOMIC_OPS_ATOMIC_H__
#if !defined(ETHR_HAVE_NATIVE_ATOMICS) && defined(ETHR_HAVE_LIBATOMIC_OPS)
#define ETHR_HAVE_NATIVE_ATOMICS 1
#if (defined(__i386__) && !defined(ETHR_PRE_PENTIUM4_COMPAT)) \
|| defined(__x86_64__)
#define AO_USE_PENTIUM4_INSTRS
#endif
#include "atomic_ops.h"
/*
* libatomic_ops can be downloaded from:
* http://www.hpl.hp.com/research/linux/atomic_ops/
*
* These operations need to be defined by libatomic_ops;
* otherwise, we won't compile:
* - AO_nop_full()
* - AO_load()
* - AO_store()
* - AO_compare_and_swap()
*
* The `AO_t' type also have to be at least as large as the `void *' type.
*/
#if ETHR_SIZEOF_AO_T < ETHR_SIZEOF_PTR
#error The AO_t type is too small
#endif
typedef struct {
volatile AO_t counter;
} ethr_native_atomic_t;
#define ETHR_MEMORY_BARRIER AO_nop_full()
#ifdef AO_HAVE_nop_write
# define ETHR_WRITE_MEMORY_BARRIER AO_nop_write()
#else
# define ETHR_WRITE_MEMORY_BARRIER ETHR_MEMORY_BARRIER
#endif
#ifdef AO_HAVE_nop_read
# define ETHR_READ_MEMORY_BARRIER AO_nop_read()
#else
# define ETHR_READ_MEMORY_BARRIER ETHR_MEMORY_BARRIER
#endif
#ifdef AO_NO_DD_ORDERING
# define ETHR_READ_DEPEND_MEMORY_BARRIER ETHR_READ_MEMORY_BARRIER
#else
# define ETHR_READ_DEPEND_MEMORY_BARRIER __asm__ __volatile__("":::"memory")
#endif
#if defined(ETHR_TRY_INLINE_FUNCS) || defined(ETHR_AUX_IMPL__)
static ETHR_INLINE void
ethr_native_atomic_set(ethr_native_atomic_t *var, ethr_sint_t value)
{
AO_store(&var->counter, (AO_t) value);
}
static ETHR_INLINE void
ethr_native_atomic_init(ethr_native_atomic_t *var, ethr_sint_t value)
{
ethr_native_atomic_set(var, value);
}
static ETHR_INLINE ethr_sint_t
ethr_native_atomic_read(ethr_native_atomic_t *var)
{
return (ethr_sint_t) AO_load(&var->counter);
}
static ETHR_INLINE ethr_sint_t
ethr_native_atomic_add_return(ethr_native_atomic_t *var, ethr_sint_t incr)
{
#ifdef AO_HAVE_fetch_and_add
return ((ethr_sint_t) AO_fetch_and_add(&var->counter, (AO_t) incr)) + incr;
#else
while (1) {
AO_t exp = AO_load(&var->counter);
AO_t new = exp + (AO_t) incr;
if (AO_compare_and_swap(&var->counter, exp, new))
return (ethr_sint_t) new;
}
#endif
}
static ETHR_INLINE void
ethr_native_atomic_add(ethr_native_atomic_t *var, ethr_sint_t incr)
{
(void) ethr_native_atomic_add_return(var, incr);
}
static ETHR_INLINE ethr_sint_t
ethr_native_atomic_inc_return(ethr_native_atomic_t *var)
{
#ifdef AO_HAVE_fetch_and_add1
return ((ethr_sint_t) AO_fetch_and_add1(&var->counter)) + 1;
#else
return ethr_native_atomic_add_return(var, 1);
#endif
}
static ETHR_INLINE void
ethr_native_atomic_inc(ethr_native_atomic_t *var)
{
(void) ethr_native_atomic_inc_return(var);
}
static ETHR_INLINE ethr_sint_t
ethr_native_atomic_dec_return(ethr_native_atomic_t *var)
{
#ifdef AO_HAVE_fetch_and_sub1
return ((ethr_sint_t) AO_fetch_and_sub1(&var->counter)) - 1;
#else
return ethr_native_atomic_add_return(var, -1);
#endif
}
static ETHR_INLINE void
ethr_native_atomic_dec(ethr_native_atomic_t *var)
{
(void) ethr_native_atomic_dec_return(var);
}
static ETHR_INLINE ethr_sint_t
ethr_native_atomic_and_retold(ethr_native_atomic_t *var, ethr_sint_t mask)
{
while (1) {
AO_t exp = AO_load(&var->counter);
AO_t new = exp & ((AO_t) mask);
if (AO_compare_and_swap(&var->counter, exp, new))
return (ethr_sint_t) exp;
}
}
static ETHR_INLINE ethr_sint_t
ethr_native_atomic_or_retold(ethr_native_atomic_t *var, ethr_sint_t mask)
{
while (1) {
AO_t exp = AO_load(&var->counter);
AO_t new = exp | ((AO_t) mask);
if (AO_compare_and_swap(&var->counter, exp, new))
return (ethr_sint_t) exp;
}
}
static ETHR_INLINE ethr_sint_t
ethr_native_atomic_cmpxchg(ethr_native_atomic_t *var,
ethr_sint_t new,
ethr_sint_t exp)
{
ethr_sint_t act;
do {
if (AO_compare_and_swap(&var->counter, (AO_t) exp, (AO_t) new))
return exp;
act = (ethr_sint_t) AO_load(&var->counter);
} while (act == exp);
return act;
}
static ETHR_INLINE ethr_sint_t
ethr_native_atomic_xchg(ethr_native_atomic_t *var, ethr_sint_t new)
{
while (1) {
AO_t exp = AO_load(&var->counter);
if (AO_compare_and_swap(&var->counter, exp, (AO_t) new))
return (ethr_sint_t) exp;
}
}
/*
* Atomic ops with at least specified barriers.
*/
static ETHR_INLINE ethr_sint_t
ethr_native_atomic_read_acqb(ethr_native_atomic_t *var)
{
#ifdef AO_HAVE_load_acquire
return (ethr_sint_t) AO_load_acquire(&var->counter);
#else
ethr_sint_t res = ethr_native_atomic_read(var);
ETHR_MEMORY_BARRIER;
return res;
#endif
}
static ETHR_INLINE ethr_sint_t
ethr_native_atomic_inc_return_acqb(ethr_native_atomic_t *var)
{
#ifdef AO_HAVE_fetch_and_add1_acquire
return ((ethr_sint_t) AO_fetch_and_add1_acquire(&var->counter)) + 1;
#else
ethr_sint_t res = ethr_native_atomic_add_return(var, 1);
ETHR_MEMORY_BARRIER;
return res;
#endif
}
static ETHR_INLINE void
ethr_native_atomic_set_relb(ethr_native_atomic_t *var, ethr_sint_t value)
{
#ifdef AO_HAVE_store_release
AO_store_release(&var->counter, (AO_t) value);
#else
ETHR_MEMORY_BARRIER;
ethr_native_atomic_set(var, value);
#endif
}
static ETHR_INLINE ethr_sint_t
ethr_native_atomic_dec_return_relb(ethr_native_atomic_t *var)
{
#ifdef AO_HAVE_fetch_and_sub1_release
return ((ethr_sint_t) AO_fetch_and_sub1_release(&var->counter)) - 1;
#else
ETHR_MEMORY_BARRIER;
return ethr_native_atomic_dec_return(var);
#endif
}
static ETHR_INLINE void
ethr_native_atomic_dec_relb(ethr_native_atomic_t *var)
{
(void) ethr_native_atomic_dec_return_relb(var);
}
static ETHR_INLINE ethr_sint_t
ethr_native_atomic_cmpxchg_acqb(ethr_native_atomic_t *var,
ethr_sint_t new,
ethr_sint_t exp)
{
#ifdef AO_HAVE_compare_and_swap_acquire
ethr_sint_t act;
do {
if (AO_compare_and_swap_acquire(&var->counter, (AO_t) exp, (AO_t) new))
return exp;
act = (ethr_sint_t) AO_load(&var->counter);
} while (act == exp);
AO_nop_full();
return act;
#else
ethr_sint_t act = ethr_native_atomic_cmpxchg(var, new, exp);
ETHR_MEMORY_BARRIER;
return act;
#endif
}
static ETHR_INLINE ethr_sint_t
ethr_native_atomic_cmpxchg_relb(ethr_native_atomic_t *var,
ethr_sint_t new,
ethr_sint_t exp)
{
#ifdef AO_HAVE_compare_and_swap_release
ethr_sint_t act;
do {
if (AO_compare_and_swap_release(&var->counter, (AO_t) exp, (AO_t) new))
return exp;
act = (ethr_sint_t) AO_load(&var->counter);
} while (act == exp);
return act;
#else
ETHR_MEMORY_BARRIER;
return ethr_native_atomic_cmpxchg(var, new, exp);
#endif
}
#endif
#endif
#endif
|
