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
|
/* Low-level functions for atomic operations. Sparc32 version.
Copyright (C) 1999 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#ifndef _ATOMICITY_H
#define _ATOMICITY_H 1
#include <inttypes.h>
static int
__attribute_used__
exchange_and_add (volatile uint32_t *mem, int val)
{
static unsigned char lock;
int result, tmp;
__asm__ __volatile__("1: ldstub [%1], %0\n\t"
" cmp %0, 0\n\t"
" bne 1b\n\t"
" nop"
: "=&r" (tmp)
: "r" (&lock)
: "memory");
result = *mem;
*mem += val;
__asm__ __volatile__("stb %%g0, [%0]"
: /* no outputs */
: "r" (&lock)
: "memory");
return result;
}
static void
__attribute_used__
atomic_add (volatile uint32_t *mem, int val)
{
static unsigned char lock;
int tmp;
__asm__ __volatile__("1: ldstub [%1], %0\n\t"
" cmp %0, 0\n\t"
" bne 1b\n\t"
" nop"
: "=&r" (tmp)
: "r" (&lock)
: "memory");
*mem += val;
__asm__ __volatile__("stb %%g0, [%0]"
: /* no outputs */
: "r" (&lock)
: "memory");
}
static int
__attribute_used__
compare_and_swap (volatile long int *p, long int oldval, long int newval)
{
static unsigned char lock;
int ret, tmp;
__asm__ __volatile__("1: ldstub [%1], %0\n\t"
" cmp %0, 0\n\t"
" bne 1b\n\t"
" nop"
: "=&r" (tmp)
: "r" (&lock)
: "memory");
if (*p != oldval)
ret = 0;
else
{
*p = newval;
ret = 1;
}
__asm__ __volatile__("stb %%g0, [%0]"
: /* no outputs */
: "r" (&lock)
: "memory");
return ret;
}
#endif /* atomicity.h */
|
