ngx_atomic.h revision e18a033b
1
2/*
3 * Copyright (C) Igor Sysoev
4 * Copyright (C) Nginx, Inc.
5 */
6
7
8#ifndef _NGX_ATOMIC_H_INCLUDED_
9#define _NGX_ATOMIC_H_INCLUDED_
10
11
12#include <ngx_config.h>
13#include <ngx_core.h>
14
15
16#if (NGX_HAVE_LIBATOMIC)
17
18#define AO_REQUIRE_CAS
19#include <atomic_ops.h>
20
21#define NGX_HAVE_ATOMIC_OPS  1
22
23typedef long                        ngx_atomic_int_t;
24typedef AO_t                        ngx_atomic_uint_t;
25typedef volatile ngx_atomic_uint_t  ngx_atomic_t;
26
27#if (NGX_PTR_SIZE == 8)
28#define NGX_ATOMIC_T_LEN            (sizeof("-9223372036854775808") - 1)
29#else
30#define NGX_ATOMIC_T_LEN            (sizeof("-2147483648") - 1)
31#endif
32
33#define ngx_atomic_cmp_set(lock, old, new)                                    \
34    AO_compare_and_swap(lock, old, new)
35#define ngx_atomic_fetch_add(value, add)                                      \
36    AO_fetch_and_add(value, add)
37#define ngx_memory_barrier()        AO_nop()
38#define ngx_cpu_pause()
39
40
41#elif (NGX_DARWIN_ATOMIC)
42
43/*
44 * use Darwin 8 atomic(3) and barrier(3) operations
45 * optimized at run-time for UP and SMP
46 */
47
48#include <libkern/OSAtomic.h>
49
50/* "bool" conflicts with perl's CORE/handy.h */
51#if 0
52#undef bool
53#endif
54
55
56#define NGX_HAVE_ATOMIC_OPS  1
57
58#if (NGX_PTR_SIZE == 8)
59
60typedef int64_t                     ngx_atomic_int_t;
61typedef uint64_t                    ngx_atomic_uint_t;
62#define NGX_ATOMIC_T_LEN            (sizeof("-9223372036854775808") - 1)
63
64#define ngx_atomic_cmp_set(lock, old, new)                                    \
65    OSAtomicCompareAndSwap64Barrier(old, new, (int64_t *) lock)
66
67#define ngx_atomic_fetch_add(value, add)                                      \
68    (OSAtomicAdd64(add, (int64_t *) value) - add)
69
70#else
71
72typedef int32_t                     ngx_atomic_int_t;
73typedef uint32_t                    ngx_atomic_uint_t;
74#define NGX_ATOMIC_T_LEN            (sizeof("-2147483648") - 1)
75
76#define ngx_atomic_cmp_set(lock, old, new)                                    \
77    OSAtomicCompareAndSwap32Barrier(old, new, (int32_t *) lock)
78
79#define ngx_atomic_fetch_add(value, add)                                      \
80    (OSAtomicAdd32(add, (int32_t *) value) - add)
81
82#endif
83
84#define ngx_memory_barrier()        OSMemoryBarrier()
85
86#define ngx_cpu_pause()
87
88typedef volatile ngx_atomic_uint_t  ngx_atomic_t;
89
90
91#elif (NGX_HAVE_GCC_ATOMIC)
92
93/* GCC 4.1 builtin atomic operations */
94
95#define NGX_HAVE_ATOMIC_OPS  1
96
97typedef long                        ngx_atomic_int_t;
98typedef unsigned long               ngx_atomic_uint_t;
99
100#if (NGX_PTR_SIZE == 8)
101#define NGX_ATOMIC_T_LEN            (sizeof("-9223372036854775808") - 1)
102#else
103#define NGX_ATOMIC_T_LEN            (sizeof("-2147483648") - 1)
104#endif
105
106typedef volatile ngx_atomic_uint_t  ngx_atomic_t;
107
108
109#define ngx_atomic_cmp_set(lock, old, set)                                    \
110    __sync_bool_compare_and_swap(lock, old, set)
111
112#define ngx_atomic_fetch_add(value, add)                                      \
113    __sync_fetch_and_add(value, add)
114
115#define ngx_memory_barrier()        __sync_synchronize()
116
117#if ( __i386__ || __i386 || __amd64__ || __amd64 )
118#define ngx_cpu_pause()             __asm__ ("pause")
119#else
120#define ngx_cpu_pause()
121#endif
122
123
124#elif ( __i386__ || __i386 )
125
126typedef int32_t                     ngx_atomic_int_t;
127typedef uint32_t                    ngx_atomic_uint_t;
128typedef volatile ngx_atomic_uint_t  ngx_atomic_t;
129#define NGX_ATOMIC_T_LEN            (sizeof("-2147483648") - 1)
130
131
132#if ( __SUNPRO_C )
133
134#define NGX_HAVE_ATOMIC_OPS  1
135
136ngx_atomic_uint_t
137ngx_atomic_cmp_set(ngx_atomic_t *lock, ngx_atomic_uint_t old,
138    ngx_atomic_uint_t set);
139
140ngx_atomic_int_t
141ngx_atomic_fetch_add(ngx_atomic_t *value, ngx_atomic_int_t add);
142
143/*
144 * Sun Studio 12 exits with segmentation fault on '__asm ("pause")',
145 * so ngx_cpu_pause is declared in src/os/unix/ngx_sunpro_x86.il
146 */
147
148void
149ngx_cpu_pause(void);
150
151/* the code in src/os/unix/ngx_sunpro_x86.il */
152
153#define ngx_memory_barrier()        __asm (".volatile"); __asm (".nonvolatile")
154
155
156#else /* ( __GNUC__ || __INTEL_COMPILER ) */
157
158#define NGX_HAVE_ATOMIC_OPS  1
159
160#include "ngx_gcc_atomic_x86.h"
161
162#endif
163
164
165#elif ( __amd64__ || __amd64 )
166
167typedef int64_t                     ngx_atomic_int_t;
168typedef uint64_t                    ngx_atomic_uint_t;
169typedef volatile ngx_atomic_uint_t  ngx_atomic_t;
170#define NGX_ATOMIC_T_LEN            (sizeof("-9223372036854775808") - 1)
171
172
173#if ( __SUNPRO_C )
174
175#define NGX_HAVE_ATOMIC_OPS  1
176
177ngx_atomic_uint_t
178ngx_atomic_cmp_set(ngx_atomic_t *lock, ngx_atomic_uint_t old,
179    ngx_atomic_uint_t set);
180
181ngx_atomic_int_t
182ngx_atomic_fetch_add(ngx_atomic_t *value, ngx_atomic_int_t add);
183
184/*
185 * Sun Studio 12 exits with segmentation fault on '__asm ("pause")',
186 * so ngx_cpu_pause is declared in src/os/unix/ngx_sunpro_amd64.il
187 */
188
189void
190ngx_cpu_pause(void);
191
192/* the code in src/os/unix/ngx_sunpro_amd64.il */
193
194#define ngx_memory_barrier()        __asm (".volatile"); __asm (".nonvolatile")
195
196
197#else /* ( __GNUC__ || __INTEL_COMPILER ) */
198
199#define NGX_HAVE_ATOMIC_OPS  1
200
201#include "ngx_gcc_atomic_amd64.h"
202
203#endif
204
205
206#elif ( __sparc__ || __sparc || __sparcv9 )
207
208#if (NGX_PTR_SIZE == 8)
209
210typedef int64_t                     ngx_atomic_int_t;
211typedef uint64_t                    ngx_atomic_uint_t;
212#define NGX_ATOMIC_T_LEN            (sizeof("-9223372036854775808") - 1)
213
214#else
215
216typedef int32_t                     ngx_atomic_int_t;
217typedef uint32_t                    ngx_atomic_uint_t;
218#define NGX_ATOMIC_T_LEN            (sizeof("-2147483648") - 1)
219
220#endif
221
222typedef volatile ngx_atomic_uint_t  ngx_atomic_t;
223
224
225#if ( __SUNPRO_C )
226
227#define NGX_HAVE_ATOMIC_OPS  1
228
229#include "ngx_sunpro_atomic_sparc64.h"
230
231
232#else /* ( __GNUC__ || __INTEL_COMPILER ) */
233
234#define NGX_HAVE_ATOMIC_OPS  1
235
236#include "ngx_gcc_atomic_sparc64.h"
237
238#endif
239
240
241#elif ( __powerpc__ || __POWERPC__ )
242
243#define NGX_HAVE_ATOMIC_OPS  1
244
245#if (NGX_PTR_SIZE == 8)
246
247typedef int64_t                     ngx_atomic_int_t;
248typedef uint64_t                    ngx_atomic_uint_t;
249#define NGX_ATOMIC_T_LEN            (sizeof("-9223372036854775808") - 1)
250
251#else
252
253typedef int32_t                     ngx_atomic_int_t;
254typedef uint32_t                    ngx_atomic_uint_t;
255#define NGX_ATOMIC_T_LEN            (sizeof("-2147483648") - 1)
256
257#endif
258
259typedef volatile ngx_atomic_uint_t  ngx_atomic_t;
260
261
262#include "ngx_gcc_atomic_ppc.h"
263
264#endif
265
266
267#if !(NGX_HAVE_ATOMIC_OPS)
268
269#define NGX_HAVE_ATOMIC_OPS  0
270
271typedef int32_t                     ngx_atomic_int_t;
272typedef uint32_t                    ngx_atomic_uint_t;
273typedef volatile ngx_atomic_uint_t  ngx_atomic_t;
274#define NGX_ATOMIC_T_LEN            (sizeof("-2147483648") - 1)
275
276
277static ngx_inline ngx_atomic_uint_t
278ngx_atomic_cmp_set(ngx_atomic_t *lock, ngx_atomic_uint_t old,
279    ngx_atomic_uint_t set)
280{
281    if (*lock == old) {
282        *lock = set;
283        return 1;
284    }
285
286    return 0;
287}
288
289
290static ngx_inline ngx_atomic_int_t
291ngx_atomic_fetch_add(ngx_atomic_t *value, ngx_atomic_int_t add)
292{
293    ngx_atomic_int_t  old;
294
295    old = *value;
296    *value += add;
297
298    return old;
299}
300
301#define ngx_memory_barrier()
302#define ngx_cpu_pause()
303
304#endif
305
306
307void ngx_spinlock(ngx_atomic_t *lock, ngx_atomic_int_t value, ngx_uint_t spin);
308
309#define ngx_trylock(lock)  (*(lock) == 0 && ngx_atomic_cmp_set(lock, 0, 1))
310#define ngx_unlock(lock)    *(lock) = 0
311
312
313#endif /* _NGX_ATOMIC_H_INCLUDED_ */
314