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
13typedef 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 */
30static 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
44static 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
59static inline long local_cmpxchg(local_t *l, long old, long new)
60{
61	return cmpxchg_local(&l->a.counter, old, new);
62}
63
64static 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