xref: /freebsd/sys/compat/linuxkpi/common/include/asm/atomic64.h (revision 7fdf597e96a02165cfe22ff357b857d5fa15ed8a)
1 /*-
2  * Copyright (c) 2016-2017 Mellanox Technologies, Ltd.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice unmodified, this list of conditions, and the following
10  *    disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 #ifndef	_LINUXKPI_ASM_ATOMIC64_H_
27 #define	_LINUXKPI_ASM_ATOMIC64_H_
28 
29 #include <linux/compiler.h>
30 #include <sys/types.h>
31 #include <machine/atomic.h>
32 
33 typedef struct {
34 	volatile int64_t counter;
35 } atomic64_t;
36 #define	ATOMIC64_INIT(x)	{ .counter = (x) }
37 
38 /*------------------------------------------------------------------------*
39  *	64-bit atomic operations
40  *------------------------------------------------------------------------*/
41 
42 #define	atomic64_add(i, v)		atomic64_add_return((i), (v))
43 #define	atomic64_sub(i, v)		atomic64_sub_return((i), (v))
44 #define	atomic64_inc_return(v)		atomic64_add_return(1, (v))
45 #define	atomic64_add_negative(i, v)	(atomic64_add_return((i), (v)) < 0)
46 #define	atomic64_add_and_test(i, v)	(atomic64_add_return((i), (v)) == 0)
47 #define	atomic64_sub_and_test(i, v)	(atomic64_sub_return((i), (v)) == 0)
48 #define	atomic64_dec_and_test(v)	(atomic64_sub_return(1, (v)) == 0)
49 #define	atomic64_inc_and_test(v)	(atomic64_add_return(1, (v)) == 0)
50 #define	atomic64_dec_return(v)		atomic64_sub_return(1, (v))
51 #define	atomic64_inc_not_zero(v)	atomic64_add_unless((v), 1, 0)
52 
53 static inline int64_t
54 atomic64_fetch_add(int64_t i, atomic64_t *v)
55 {
56 	return (atomic_fetchadd_64(&v->counter, i));
57 }
58 
59 static inline int64_t
60 atomic64_add_return(int64_t i, atomic64_t *v)
61 {
62 	return i + atomic_fetchadd_64(&v->counter, i);
63 }
64 
65 static inline int64_t
66 atomic64_sub_return(int64_t i, atomic64_t *v)
67 {
68 	return atomic_fetchadd_64(&v->counter, -i) - i;
69 }
70 
71 static inline void
72 atomic64_set(atomic64_t *v, int64_t i)
73 {
74 	atomic_store_rel_64(&v->counter, i);
75 }
76 
77 static inline int64_t
78 atomic64_read(atomic64_t *v)
79 {
80 	return READ_ONCE(v->counter);
81 }
82 
83 static inline int64_t
84 atomic64_inc(atomic64_t *v)
85 {
86 	return atomic_fetchadd_64(&v->counter, 1) + 1;
87 }
88 
89 static inline int64_t
90 atomic64_dec(atomic64_t *v)
91 {
92 	return atomic_fetchadd_64(&v->counter, -1) - 1;
93 }
94 
95 static inline int64_t
96 atomic64_add_unless(atomic64_t *v, int64_t a, int64_t u)
97 {
98 	int64_t c = atomic64_read(v);
99 
100 	for (;;) {
101 		if (unlikely(c == u))
102 			break;
103 		if (likely(atomic_fcmpset_64(&v->counter, &c, c + a)))
104 			break;
105 	}
106 	return (c != u);
107 }
108 
109 static inline int64_t
110 atomic64_fetch_add_unless(atomic64_t *v, int64_t a, int64_t u)
111 {
112 	int64_t c = atomic64_read(v);
113 
114 	for (;;) {
115 		if (unlikely(c == u))
116 			break;
117 		if (likely(atomic_fcmpset_64(&v->counter, &c, c + a)))
118 			break;
119 	}
120 	return (c);
121 }
122 
123 static inline int64_t
124 atomic64_xchg(atomic64_t *v, int64_t i)
125 {
126 #if !(defined(__powerpc__) && !defined(__powerpc64__))
127 	return (atomic_swap_64(&v->counter, i));
128 #else
129 	int64_t ret = atomic64_read(v);
130 
131 	while (!atomic_fcmpset_64(&v->counter, &ret, i))
132 		;
133 	return (ret);
134 #endif
135 }
136 
137 static inline int64_t
138 atomic64_cmpxchg(atomic64_t *v, int64_t old, int64_t new)
139 {
140 	int64_t ret = old;
141 
142 	for (;;) {
143 		if (atomic_fcmpset_64(&v->counter, &ret, new))
144 			break;
145 		if (ret != old)
146 			break;
147 	}
148 	return (ret);
149 }
150 
151 #endif					/* _LINUXKPI_ASM_ATOMIC64_H_ */
152