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comparison src/os/unix/ngx_atomic.h @ 373:018569a8f09c

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nginx-0.0.7-2004-06-30-19:30:41 import
author Igor Sysoev <igor@sysoev.ru>
date Wed, 30 Jun 2004 15:30:41 +0000
parents src/core/ngx_atomic.h@780e93985b93
children bd39260a1383
comparison
equal deleted inserted replaced
372:c9fdfccebc49 373:018569a8f09c
1 #ifndef _NGX_ATOMIC_H_INCLUDED_
2 #define _NGX_ATOMIC_H_INCLUDED_
3
4
5 #include <ngx_config.h>
6 #include <ngx_core.h>
7
8
9 #if ( __i386__ || __amd64__ )
10
11 typedef volatile uint32_t ngx_atomic_t;
12
13 #if (NGX_SMP)
14 #define NGX_SMP_LOCK "lock;"
15 #else
16 #define NGX_SMP_LOCK
17 #endif
18
19
20 static ngx_inline uint32_t ngx_atomic_inc(ngx_atomic_t *value)
21 {
22 uint32_t old;
23
24 __asm__ volatile (
25
26 NGX_SMP_LOCK
27 " xaddl %0, %2; "
28 " incl %0; "
29
30 : "=q" (old) : "0" (1), "m" (*value));
31
32 return old;
33 }
34
35
36 static ngx_inline uint32_t ngx_atomic_dec(ngx_atomic_t *value)
37 {
38 uint32_t old;
39
40 __asm__ volatile (
41
42 NGX_SMP_LOCK
43 " xaddl %0, %1; "
44 " decl %0; "
45
46 : "=q" (old) : "0" (-1), "m" (*value));
47
48 return old;
49 }
50
51
52 static ngx_inline uint32_t ngx_atomic_cmp_set(ngx_atomic_t *lock,
53 ngx_atomic_t old,
54 ngx_atomic_t set)
55 {
56 uint32_t res;
57
58 __asm__ volatile (
59
60 NGX_SMP_LOCK
61 " cmpxchgl %3, %1; "
62 " setz %%al; "
63 " movzbl %%al, %0; "
64
65 : "=a" (res) : "m" (*lock), "a" (old), "q" (set));
66
67 return res;
68 }
69
70
71 #else
72
73 typedef volatile uint32_t ngx_atomic_t;
74
75 /* STUB */
76 #define ngx_atomic_inc(x) (*(x))++;
77 #define ngx_atomic_dec(x) (*(x))--;
78 #define ngx_atomic_cmp_set(lock, old, set) 1
79 /**/
80
81 #endif
82
83
84 void ngx_spinlock(ngx_atomic_t *lock, ngx_uint_t spin);
85
86 #define ngx_trylock(lock) (*(lock) == 0 && ngx_atomic_cmp_set(lock, 0, 1))
87 #define ngx_unlock(lock) *(lock) = 0
88
89
90 #endif /* _NGX_ATOMIC_H_INCLUDED_ */