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
local_cmpxchg(local_t * l,long old,long new)55 static __inline__ long local_cmpxchg(local_t *l, long old, long new)
56 {
57 return cmpxchg_local(&l->a.counter, old, new);
58 }
59
local_try_cmpxchg(local_t * l,long * old,long new)60 static __inline__ bool local_try_cmpxchg(local_t *l, long *old, long new)
61 {
62 return try_cmpxchg_local(&l->a.counter, (s64 *)old, new);
63 }
64
65 #define local_xchg(l, n) (xchg_local(&((l)->a.counter), (n)))
66
67 /**
68 * local_add_unless - add unless the number is a given value
69 * @l: pointer of type local_t
70 * @a: the amount to add to l...
71 * @u: ...unless l is equal to u.
72 *
73 * Atomically adds @a to @l, so long as it was not @u.
74 * Returns non-zero if @l was not @u, and zero otherwise.
75 */
76 #define local_add_unless(l, a, u) \
77 ({ \
78 long c, old; \
79 c = local_read(l); \
80 for (;;) { \
81 if (unlikely(c == (u))) \
82 break; \
83 old = local_cmpxchg((l), c, c + (a)); \
84 if (likely(old == c)) \
85 break; \
86 c = old; \
87 } \
88 c != (u); \
89 })
90 #define local_inc_not_zero(l) local_add_unless((l), 1, 0)
91
92 #define local_add_negative(a, l) (local_add_return((a), (l)) < 0)
93
94 #define local_dec_return(l) local_sub_return(1,(l))
95
96 #define local_inc_return(l) local_add_return(1,(l))
97
98 #define local_sub_and_test(i,l) (local_sub_return((i), (l)) == 0)
99
100 #define local_inc_and_test(l) (local_add_return(1, (l)) == 0)
101
102 #define local_dec_and_test(l) (local_sub_return(1, (l)) == 0)
103
104 /* Verify if faster than atomic ops */
105 #define __local_inc(l) ((l)->a.counter++)
106 #define __local_dec(l) ((l)->a.counter++)
107 #define __local_add(i,l) ((l)->a.counter+=(i))
108 #define __local_sub(i,l) ((l)->a.counter-=(i))
109
110 #endif /* _ALPHA_LOCAL_H */
111