1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ALPHA_LOCAL_H
3 #define _ALPHA_LOCAL_H
4
5 #include <linux/percpu.h>
6 #include <linux/atomic.h>
7
8 typedef struct
9 {
10 atomic_long_t a;
11 } local_t;
12
13 #define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) }
14 #define local_read(l) atomic_long_read(&(l)->a)
15 #define local_set(l,i) atomic_long_set(&(l)->a, (i))
16 #define local_inc(l) atomic_long_inc(&(l)->a)
17 #define local_dec(l) atomic_long_dec(&(l)->a)
18 #define local_add(i,l) atomic_long_add((i),(&(l)->a))
19 #define local_sub(i,l) atomic_long_sub((i),(&(l)->a))
20
local_add_return(long i,local_t * l)21 static __inline__ long local_add_return(long i, local_t * l)
22 {
23 long temp, result;
24 __asm__ __volatile__(
25 "1: ldq_l %0,%1\n"
26 " addq %0,%3,%2\n"
27 " addq %0,%3,%0\n"
28 " stq_c %0,%1\n"
29 " beq %0,2f\n"
30 ".subsection 2\n"
31 "2: br 1b\n"
32 ".previous"
33 :"=&r" (temp), "=m" (l->a.counter), "=&r" (result)
34 :"Ir" (i), "m" (l->a.counter) : "memory");
35 return result;
36 }
37
local_sub_return(long i,local_t * l)38 static __inline__ long local_sub_return(long i, local_t * l)
39 {
40 long temp, result;
41 __asm__ __volatile__(
42 "1: ldq_l %0,%1\n"
43 " subq %0,%3,%2\n"
44 " subq %0,%3,%0\n"
45 " stq_c %0,%1\n"
46 " beq %0,2f\n"
47 ".subsection 2\n"
48 "2: br 1b\n"
49 ".previous"
50 :"=&r" (temp), "=m" (l->a.counter), "=&r" (result)
51 :"Ir" (i), "m" (l->a.counter) : "memory");
52 return result;
53 }
54
55 #define local_cmpxchg(l, o, n) \
56 (cmpxchg_local(&((l)->a.counter), (o), (n)))
57 #define local_xchg(l, n) (xchg_local(&((l)->a.counter), (n)))
58
59 /**
60 * local_add_unless - add unless the number is a given value
61 * @l: pointer of type local_t
62 * @a: the amount to add to l...
63 * @u: ...unless l is equal to u.
64 *
65 * Atomically adds @a to @l, so long as it was not @u.
66 * Returns non-zero if @l was not @u, and zero otherwise.
67 */
68 #define local_add_unless(l, a, u) \
69 ({ \
70 long c, old; \
71 c = local_read(l); \
72 for (;;) { \
73 if (unlikely(c == (u))) \
74 break; \
75 old = local_cmpxchg((l), c, c + (a)); \
76 if (likely(old == c)) \
77 break; \
78 c = old; \
79 } \
80 c != (u); \
81 })
82 #define local_inc_not_zero(l) local_add_unless((l), 1, 0)
83
84 #define local_add_negative(a, l) (local_add_return((a), (l)) < 0)
85
86 #define local_dec_return(l) local_sub_return(1,(l))
87
88 #define local_inc_return(l) local_add_return(1,(l))
89
90 #define local_sub_and_test(i,l) (local_sub_return((i), (l)) == 0)
91
92 #define local_inc_and_test(l) (local_add_return(1, (l)) == 0)
93
94 #define local_dec_and_test(l) (local_sub_return(1, (l)) == 0)
95
96 /* Verify if faster than atomic ops */
97 #define __local_inc(l) ((l)->a.counter++)
98 #define __local_dec(l) ((l)->a.counter++)
99 #define __local_add(i,l) ((l)->a.counter+=(i))
100 #define __local_sub(i,l) ((l)->a.counter-=(i))
101
102 #endif /* _ALPHA_LOCAL_H */
103