1#ifndef _ALPHA_LOCAL_H
2#define _ALPHA_LOCAL_H
3
4#include <linux/percpu.h>
5#include <asm/atomic.h>
6
7typedef struct
8{
9	atomic_long_t a;
10} local_t;
11
12#define LOCAL_INIT(i)	{ ATOMIC_LONG_INIT(i) }
13#define local_read(l)	atomic_long_read(&(l)->a)
14#define local_set(l,i)	atomic_long_set(&(l)->a, (i))
15#define local_inc(l)	atomic_long_inc(&(l)->a)
16#define local_dec(l)	atomic_long_dec(&(l)->a)
17#define local_add(i,l)	atomic_long_add((i),(&(l)->a))
18#define local_sub(i,l)	atomic_long_sub((i),(&(l)->a))
19
20static __inline__ long local_add_return(long i, local_t * l)
21{
22	long temp, result;
23	__asm__ __volatile__(
24	"1:	ldq_l %0,%1\n"
25	"	addq %0,%3,%2\n"
26	"	addq %0,%3,%0\n"
27	"	stq_c %0,%1\n"
28	"	beq %0,2f\n"
29	".subsection 2\n"
30	"2:	br 1b\n"
31	".previous"
32	:"=&r" (temp), "=m" (l->a.counter), "=&r" (result)
33	:"Ir" (i), "m" (l->a.counter) : "memory");
34	return result;
35}
36
37static __inline__ long local_sub_return(long i, local_t * l)
38{
39	long temp, result;
40	__asm__ __volatile__(
41	"1:	ldq_l %0,%1\n"
42	"	subq %0,%3,%2\n"
43	"	subq %0,%3,%0\n"
44	"	stq_c %0,%1\n"
45	"	beq %0,2f\n"
46	".subsection 2\n"
47	"2:	br 1b\n"
48	".previous"
49	:"=&r" (temp), "=m" (l->a.counter), "=&r" (result)
50	:"Ir" (i), "m" (l->a.counter) : "memory");
51	return result;
52}
53
54#define local_cmpxchg(l, o, n) \
55	(cmpxchg_local(&((l)->a.counter), (o), (n)))
56#define local_xchg(l, n) (xchg_local(&((l)->a.counter), (n)))
57
58/**
59 * local_add_unless - add unless the number is a given value
60 * @l: pointer of type local_t
61 * @a: the amount to add to l...
62 * @u: ...unless l is equal to u.
63 *
64 * Atomically adds @a to @l, so long as it was not @u.
65 * Returns non-zero if @l was not @u, and zero otherwise.
66 */
67#define local_add_unless(l, a, u)				\
68({								\
69	long c, old;						\
70	c = local_read(l);					\
71	for (;;) {						\
72		if (unlikely(c == (u)))				\
73			break;					\
74		old = local_cmpxchg((l), c, c + (a));	\
75		if (likely(old == c))				\
76			break;					\
77		c = old;					\
78	}							\
79	c != (u);						\
80})
81#define local_inc_not_zero(l) local_add_unless((l), 1, 0)
82
83#define local_add_negative(a, l) (local_add_return((a), (l)) < 0)
84
85#define local_dec_return(l) local_sub_return(1,(l))
86
87#define local_inc_return(l) local_add_return(1,(l))
88
89#define local_sub_and_test(i,l) (local_sub_return((i), (l)) == 0)
90
91#define local_inc_and_test(l) (local_add_return(1, (l)) == 0)
92
93#define local_dec_and_test(l) (local_sub_return(1, (l)) == 0)
94
95/* Verify if faster than atomic ops */
96#define __local_inc(l)		((l)->a.counter++)
97#define __local_dec(l)		((l)->a.counter++)
98#define __local_add(i,l)	((l)->a.counter+=(i))
99#define __local_sub(i,l)	((l)->a.counter-=(i))
100
101/* Use these for per-cpu local_t variables: on some archs they are
102 * much more efficient than these naive implementations.  Note they take
103 * a variable, not an address.
104 */
105#define cpu_local_read(l)	local_read(&__get_cpu_var(l))
106#define cpu_local_set(l, i)	local_set(&__get_cpu_var(l), (i))
107
108#define cpu_local_inc(l)	local_inc(&__get_cpu_var(l))
109#define cpu_local_dec(l)	local_dec(&__get_cpu_var(l))
110#define cpu_local_add(i, l)	local_add((i), &__get_cpu_var(l))
111#define cpu_local_sub(i, l)	local_sub((i), &__get_cpu_var(l))
112
113#define __cpu_local_inc(l)	__local_inc(&__get_cpu_var(l))
114#define __cpu_local_dec(l)	__local_dec(&__get_cpu_var(l))
115#define __cpu_local_add(i, l)	__local_add((i), &__get_cpu_var(l))
116#define __cpu_local_sub(i, l)	__local_sub((i), &__get_cpu_var(l))
117
118#endif /* _ALPHA_LOCAL_H */
119