forked from grate-driver/linux
-
Notifications
You must be signed in to change notification settings - Fork 0
/
local.h
118 lines (100 loc) · 3.31 KB
/
local.h
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
#ifndef _ALPHA_LOCAL_H
#define _ALPHA_LOCAL_H
#include <linux/percpu.h>
#include <asm/atomic.h>
typedef struct
{
atomic_long_t a;
} local_t;
#define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) }
#define local_read(l) atomic_long_read(&(l)->a)
#define local_set(l,i) atomic_long_set(&(l)->a, (i))
#define local_inc(l) atomic_long_inc(&(l)->a)
#define local_dec(l) atomic_long_dec(&(l)->a)
#define local_add(i,l) atomic_long_add((i),(&(l)->a))
#define local_sub(i,l) atomic_long_sub((i),(&(l)->a))
static __inline__ long local_add_return(long i, local_t * l)
{
long temp, result;
__asm__ __volatile__(
"1: ldq_l %0,%1\n"
" addq %0,%3,%2\n"
" addq %0,%3,%0\n"
" stq_c %0,%1\n"
" beq %0,2f\n"
".subsection 2\n"
"2: br 1b\n"
".previous"
:"=&r" (temp), "=m" (l->a.counter), "=&r" (result)
:"Ir" (i), "m" (l->a.counter) : "memory");
return result;
}
static __inline__ long local_sub_return(long i, local_t * l)
{
long temp, result;
__asm__ __volatile__(
"1: ldq_l %0,%1\n"
" subq %0,%3,%2\n"
" subq %0,%3,%0\n"
" stq_c %0,%1\n"
" beq %0,2f\n"
".subsection 2\n"
"2: br 1b\n"
".previous"
:"=&r" (temp), "=m" (l->a.counter), "=&r" (result)
:"Ir" (i), "m" (l->a.counter) : "memory");
return result;
}
#define local_cmpxchg(l, o, n) \
(cmpxchg_local(&((l)->a.counter), (o), (n)))
#define local_xchg(l, n) (xchg_local(&((l)->a.counter), (n)))
/**
* local_add_unless - add unless the number is a given value
* @l: pointer of type local_t
* @a: the amount to add to l...
* @u: ...unless l is equal to u.
*
* Atomically adds @a to @l, so long as it was not @u.
* Returns non-zero if @l was not @u, and zero otherwise.
*/
#define local_add_unless(l, a, u) \
({ \
long c, old; \
c = local_read(l); \
for (;;) { \
if (unlikely(c == (u))) \
break; \
old = local_cmpxchg((l), c, c + (a)); \
if (likely(old == c)) \
break; \
c = old; \
} \
c != (u); \
})
#define local_inc_not_zero(l) local_add_unless((l), 1, 0)
#define local_add_negative(a, l) (local_add_return((a), (l)) < 0)
#define local_dec_return(l) local_sub_return(1,(l))
#define local_inc_return(l) local_add_return(1,(l))
#define local_sub_and_test(i,l) (local_sub_return((i), (l)) == 0)
#define local_inc_and_test(l) (local_add_return(1, (l)) == 0)
#define local_dec_and_test(l) (local_sub_return(1, (l)) == 0)
/* Verify if faster than atomic ops */
#define __local_inc(l) ((l)->a.counter++)
#define __local_dec(l) ((l)->a.counter++)
#define __local_add(i,l) ((l)->a.counter+=(i))
#define __local_sub(i,l) ((l)->a.counter-=(i))
/* Use these for per-cpu local_t variables: on some archs they are
* much more efficient than these naive implementations. Note they take
* a variable, not an address.
*/
#define cpu_local_read(l) local_read(&__get_cpu_var(l))
#define cpu_local_set(l, i) local_set(&__get_cpu_var(l), (i))
#define cpu_local_inc(l) local_inc(&__get_cpu_var(l))
#define cpu_local_dec(l) local_dec(&__get_cpu_var(l))
#define cpu_local_add(i, l) local_add((i), &__get_cpu_var(l))
#define cpu_local_sub(i, l) local_sub((i), &__get_cpu_var(l))
#define __cpu_local_inc(l) __local_inc(&__get_cpu_var(l))
#define __cpu_local_dec(l) __local_dec(&__get_cpu_var(l))
#define __cpu_local_add(i, l) __local_add((i), &__get_cpu_var(l))
#define __cpu_local_sub(i, l) __local_sub((i), &__get_cpu_var(l))
#endif /* _ALPHA_LOCAL_H */