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
|
/*
* arch/s390/lib/spinlock.c
* Out of line spinlock code.
*
* S390 version
* Copyright (C) 2004 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
*/
#include <linux/types.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/init.h>
#include <asm/io.h>
atomic_t spin_retry_counter;
int spin_retry = 1000;
/**
* spin_retry= parameter
*/
static int __init spin_retry_setup(char *str)
{
spin_retry = simple_strtoul(str, &str, 0);
return 1;
}
__setup("spin_retry=", spin_retry_setup);
static inline void
_diag44(void)
{
#ifdef __s390x__
if (MACHINE_HAS_DIAG44)
#endif
asm volatile("diag 0,0,0x44");
}
void
_raw_spin_lock_wait(spinlock_t *lp, unsigned int pc)
{
int count = spin_retry;
while (1) {
if (count-- <= 0) {
_diag44();
count = spin_retry;
}
atomic_inc(&spin_retry_counter);
if (_raw_compare_and_swap(&lp->lock, 0, pc) == 0)
return;
}
}
EXPORT_SYMBOL(_raw_spin_lock_wait);
int
_raw_spin_trylock_retry(spinlock_t *lp, unsigned int pc)
{
int count = spin_retry;
while (count-- > 0) {
atomic_inc(&spin_retry_counter);
if (_raw_compare_and_swap(&lp->lock, 0, pc) == 0)
return 1;
}
return 0;
}
EXPORT_SYMBOL(_raw_spin_trylock_retry);
void
_raw_read_lock_wait(rwlock_t *rw)
{
unsigned int old;
int count = spin_retry;
while (1) {
if (count-- <= 0) {
_diag44();
count = spin_retry;
}
atomic_inc(&spin_retry_counter);
old = rw->lock & 0x7fffffffU;
if (_raw_compare_and_swap(&rw->lock, old, old + 1) == old)
return;
}
}
EXPORT_SYMBOL(_raw_read_lock_wait);
int
_raw_read_trylock_retry(rwlock_t *rw)
{
unsigned int old;
int count = spin_retry;
while (count-- > 0) {
atomic_inc(&spin_retry_counter);
old = rw->lock & 0x7fffffffU;
if (_raw_compare_and_swap(&rw->lock, old, old + 1) == old)
return 1;
}
return 0;
}
EXPORT_SYMBOL(_raw_read_trylock_retry);
void
_raw_write_lock_wait(rwlock_t *rw)
{
int count = spin_retry;
while (1) {
if (count-- <= 0) {
_diag44();
count = spin_retry;
}
atomic_inc(&spin_retry_counter);
if (_raw_compare_and_swap(&rw->lock, 0, 0x80000000) == 0)
return;
}
}
EXPORT_SYMBOL(_raw_write_lock_wait);
int
_raw_write_trylock_retry(rwlock_t *rw)
{
int count = spin_retry;
while (count-- > 0) {
atomic_inc(&spin_retry_counter);
if (_raw_compare_and_swap(&rw->lock, 0, 0x80000000) == 0)
return 1;
}
return 0;
}
EXPORT_SYMBOL(_raw_write_trylock_retry);
|
