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comparison src/os/unix/ngx_atomic.h @ 0:f0b350454894 NGINX_0_1_0

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nginx 0.1.0 *) The first public version.
author Igor Sysoev <http://sysoev.ru>
date Mon, 04 Oct 2004 00:00:00 +0400
parents
children 41ccba1aba45
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-1:000000000000 0:f0b350454894
1
2 /*
3 * Copyright (C) Igor Sysoev
4 */
5
6
7 #ifndef _NGX_ATOMIC_H_INCLUDED_
8 #define _NGX_ATOMIC_H_INCLUDED_
9
10
11 #include <ngx_config.h>
12 #include <ngx_core.h>
13
14
15 #if ( __i386__ || __amd64__ )
16
17 #define NGX_HAVE_ATOMIC_OPS 1
18
19 typedef volatile uint32_t ngx_atomic_t;
20
21 #if (NGX_SMP)
22 #define NGX_SMP_LOCK "lock;"
23 #else
24 #define NGX_SMP_LOCK
25 #endif
26
27
28 static ngx_inline uint32_t ngx_atomic_inc(ngx_atomic_t *value)
29 {
30 uint32_t old;
31
32 __asm__ volatile (
33
34 NGX_SMP_LOCK
35 " xaddl %0, %2; "
36 " incl %0; "
37
38 : "=q" (old) : "0" (1), "m" (*value));
39
40 return old;
41 }
42
43
44 #if 0
45
46 static ngx_inline uint32_t ngx_atomic_dec(ngx_atomic_t *value)
47 {
48 uint32_t old;
49
50 __asm__ volatile (
51
52 NGX_SMP_LOCK
53 " xaddl %0, %1; "
54 " decl %0; "
55
56 : "=q" (old) : "0" (-1), "m" (*value));
57
58 return old;
59 }
60
61 #endif
62
63
64 static ngx_inline uint32_t ngx_atomic_cmp_set(ngx_atomic_t *lock,
65 ngx_atomic_t old,
66 ngx_atomic_t set)
67 {
68 uint32_t res;
69
70 __asm__ volatile (
71
72 NGX_SMP_LOCK
73 " cmpxchgl %3, %1; "
74 " setz %%al; "
75 " movzbl %%al, %0; "
76
77 : "=a" (res) : "m" (*lock), "a" (old), "q" (set));
78
79 return res;
80 }
81
82
83 #elif ( __sparc__ )
84
85 #define NGX_HAVE_ATOMIC_OPS 1
86
87 typedef volatile uint32_t ngx_atomic_t;
88
89
90 static ngx_inline uint32_t ngx_atomic_inc(ngx_atomic_t *value)
91 {
92 uint32_t old, new, res;
93
94 old = *value;
95
96 for ( ;; ) {
97
98 new = old + 1;
99 res = new;
100
101 __asm__ volatile (
102
103 "casa [%1] 0x80, %2, %0"
104
105 : "+r" (res) : "r" (value), "r" (old));
106
107 if (res == old) {
108 return new;
109 }
110
111 old = res;
112 }
113 }
114
115
116 static ngx_inline uint32_t ngx_atomic_cmp_set(ngx_atomic_t *lock,
117 ngx_atomic_t old,
118 ngx_atomic_t set)
119 {
120 uint32_t res = (uint32_t) set;
121
122 __asm__ volatile (
123
124 "casa [%1] 0x80, %2, %0"
125
126 : "+r" (res) : "r" (lock), "r" (old));
127
128 return (res == old);
129 }
130
131 #else
132
133 #define NGX_HAVE_ATOMIC_OPS 0
134
135 typedef volatile uint32_t ngx_atomic_t;
136
137 #define ngx_atomic_inc(x) ++(*(x));
138
139 static ngx_inline uint32_t ngx_atomic_cmp_set(ngx_atomic_t *lock,
140 ngx_atomic_t old,
141 ngx_atomic_t set)
142 {
143 return 1;
144 }
145
146 #endif
147
148
149 void ngx_spinlock(ngx_atomic_t *lock, ngx_uint_t spin);
150
151 #define ngx_trylock(lock) (*(lock) == 0 && ngx_atomic_cmp_set(lock, 0, 1))
152 #define ngx_unlock(lock) *(lock) = 0
153
154
155 #endif /* _NGX_ATOMIC_H_INCLUDED_ */