1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
4 */
5 #ifndef _ARCH_LOONGARCH_LOCAL_H
6 #define _ARCH_LOONGARCH_LOCAL_H
7
8 #include <linux/percpu.h>
9 #include <linux/bitops.h>
10 #include <linux/atomic.h>
11 #include <asm/cmpxchg.h>
12
13 typedef struct {
14 atomic_long_t a;
15 } local_t;
16
17 #define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) }
18
19 #define local_read(l) atomic_long_read(&(l)->a)
20 #define local_set(l, i) atomic_long_set(&(l)->a, (i))
21
22 #define local_add(i, l) atomic_long_add((i), (&(l)->a))
23 #define local_sub(i, l) atomic_long_sub((i), (&(l)->a))
24 #define local_inc(l) atomic_long_inc(&(l)->a)
25 #define local_dec(l) atomic_long_dec(&(l)->a)
26
27 /*
28 * Same as above, but return the result value
29 */
local_add_return(long i,local_t * l)30 static inline long local_add_return(long i, local_t *l)
31 {
32 unsigned long result;
33
34 __asm__ __volatile__(
35 " " __AMADD " %1, %2, %0 \n"
36 : "+ZB" (l->a.counter), "=&r" (result)
37 : "r" (i)
38 : "memory");
39 result = result + i;
40
41 return result;
42 }
43
local_sub_return(long i,local_t * l)44 static inline long local_sub_return(long i, local_t *l)
45 {
46 unsigned long result;
47
48 __asm__ __volatile__(
49 " " __AMADD "%1, %2, %0 \n"
50 : "+ZB" (l->a.counter), "=&r" (result)
51 : "r" (-i)
52 : "memory");
53
54 result = result - i;
55
56 return result;
57 }
58
local_cmpxchg(local_t * l,long old,long new)59 static inline long local_cmpxchg(local_t *l, long old, long new)
60 {
61 return cmpxchg_local(&l->a.counter, old, new);
62 }
63
local_try_cmpxchg(local_t * l,long * old,long new)64 static inline bool local_try_cmpxchg(local_t *l, long *old, long new)
65 {
66 return try_cmpxchg_local(&l->a.counter,
67 (typeof(l->a.counter) *) old, new);
68 }
69
70 #define local_xchg(l, n) (atomic_long_xchg((&(l)->a), (n)))
71
72 /**
73 * local_add_unless - add unless the number is a given value
74 * @l: pointer of type local_t
75 * @a: the amount to add to l...
76 * @u: ...unless l is equal to u.
77 *
78 * Atomically adds @a to @l, so long as it was not @u.
79 * Returns non-zero if @l was not @u, and zero otherwise.
80 */
81 #define local_add_unless(l, a, u) \
82 ({ \
83 long c, old; \
84 c = local_read(l); \
85 while (c != (u) && (old = local_cmpxchg((l), c, c + (a))) != c) \
86 c = old; \
87 c != (u); \
88 })
89 #define local_inc_not_zero(l) local_add_unless((l), 1, 0)
90
91 #define local_dec_return(l) local_sub_return(1, (l))
92 #define local_inc_return(l) local_add_return(1, (l))
93
94 /*
95 * local_sub_and_test - subtract value from variable and test result
96 * @i: integer value to subtract
97 * @l: pointer of type local_t
98 *
99 * Atomically subtracts @i from @l and returns
100 * true if the result is zero, or false for all
101 * other cases.
102 */
103 #define local_sub_and_test(i, l) (local_sub_return((i), (l)) == 0)
104
105 /*
106 * local_inc_and_test - increment and test
107 * @l: pointer of type local_t
108 *
109 * Atomically increments @l by 1
110 * and returns true if the result is zero, or false for all
111 * other cases.
112 */
113 #define local_inc_and_test(l) (local_inc_return(l) == 0)
114
115 /*
116 * local_dec_and_test - decrement by 1 and test
117 * @l: pointer of type local_t
118 *
119 * Atomically decrements @l by 1 and
120 * returns true if the result is 0, or false for all other
121 * cases.
122 */
123 #define local_dec_and_test(l) (local_sub_return(1, (l)) == 0)
124
125 /*
126 * local_add_negative - add and test if negative
127 * @l: pointer of type local_t
128 * @i: integer value to add
129 *
130 * Atomically adds @i to @l and returns true
131 * if the result is negative, or false when
132 * result is greater than or equal to zero.
133 */
134 #define local_add_negative(i, l) (local_add_return(i, (l)) < 0)
135
136 /* Use these for per-cpu local_t variables: on some archs they are
137 * much more efficient than these naive implementations. Note they take
138 * a variable, not an address.
139 */
140
141 #define __local_inc(l) ((l)->a.counter++)
142 #define __local_dec(l) ((l)->a.counter++)
143 #define __local_add(i, l) ((l)->a.counter += (i))
144 #define __local_sub(i, l) ((l)->a.counter -= (i))
145
146 #endif /* _ARCH_LOONGARCH_LOCAL_H */
147