1 /*
2 * Copyright (C) 2014 The Android Open Source Project
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 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in
12 * the documentation and/or other materials provided with the
13 * distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #ifndef ANDROID_CUTILS_ATOMIC_AARCH64_H
30 #define ANDROID_CUTILS_ATOMIC_AARCH64_H
31
32 #include <stdint.h>
33
34 #ifndef ANDROID_ATOMIC_INLINE
35 #define ANDROID_ATOMIC_INLINE inline __attribute__((always_inline))
36 #endif
37
38 /*
39 TODOAArch64: Revisit the below functions and check for potential
40 optimizations using assembly code or otherwise.
41 */
42
43 extern ANDROID_ATOMIC_INLINE
android_compiler_barrier(void)44 void android_compiler_barrier(void)
45 {
46 __asm__ __volatile__ ("" : : : "memory");
47 }
48
49 extern ANDROID_ATOMIC_INLINE
android_memory_barrier(void)50 void android_memory_barrier(void)
51 {
52 __asm__ __volatile__ ("dmb ish" : : : "memory");
53 }
54
55 extern ANDROID_ATOMIC_INLINE
android_atomic_acquire_load(volatile const int32_t * ptr)56 int32_t android_atomic_acquire_load(volatile const int32_t *ptr)
57 {
58 int32_t value = *ptr;
59 android_memory_barrier();
60 return value;
61 }
62
63 extern ANDROID_ATOMIC_INLINE
android_atomic_release_load(volatile const int32_t * ptr)64 int32_t android_atomic_release_load(volatile const int32_t *ptr)
65 {
66 android_memory_barrier();
67 return *ptr;
68 }
69
70 extern ANDROID_ATOMIC_INLINE
android_atomic_acquire_store(int32_t value,volatile int32_t * ptr)71 void android_atomic_acquire_store(int32_t value, volatile int32_t *ptr)
72 {
73 *ptr = value;
74 android_memory_barrier();
75 }
76
77 extern ANDROID_ATOMIC_INLINE
android_atomic_release_store(int32_t value,volatile int32_t * ptr)78 void android_atomic_release_store(int32_t value, volatile int32_t *ptr)
79 {
80 android_memory_barrier();
81 *ptr = value;
82 }
83
84 extern ANDROID_ATOMIC_INLINE
android_atomic_cas(int32_t old_value,int32_t new_value,volatile int32_t * ptr)85 int android_atomic_cas(int32_t old_value, int32_t new_value,
86 volatile int32_t *ptr)
87 {
88 return __sync_val_compare_and_swap(ptr, old_value, new_value) != old_value;
89 }
90
91 extern ANDROID_ATOMIC_INLINE
android_atomic_acquire_cas(int32_t old_value,int32_t new_value,volatile int32_t * ptr)92 int android_atomic_acquire_cas(int32_t old_value, int32_t new_value,
93 volatile int32_t *ptr)
94 {
95 int status = android_atomic_cas(old_value, new_value, ptr);
96 android_memory_barrier();
97 return status;
98 }
99
100 extern ANDROID_ATOMIC_INLINE
android_atomic_release_cas(int32_t old_value,int32_t new_value,volatile int32_t * ptr)101 int android_atomic_release_cas(int32_t old_value, int32_t new_value,
102 volatile int32_t *ptr)
103 {
104 android_memory_barrier();
105 return android_atomic_cas(old_value, new_value, ptr);
106 }
107
108 extern ANDROID_ATOMIC_INLINE
android_atomic_add(int32_t increment,volatile int32_t * ptr)109 int32_t android_atomic_add(int32_t increment, volatile int32_t *ptr)
110 {
111 int32_t prev, status;
112 android_memory_barrier();
113 do {
114 prev = *ptr;
115 status = android_atomic_cas(prev, prev + increment, ptr);
116 } while (__builtin_expect(status != 0, 0));
117 return prev;
118 }
119
120 extern ANDROID_ATOMIC_INLINE
android_atomic_inc(volatile int32_t * addr)121 int32_t android_atomic_inc(volatile int32_t *addr)
122 {
123 return android_atomic_add(1, addr);
124 }
125
126 extern ANDROID_ATOMIC_INLINE
android_atomic_dec(volatile int32_t * addr)127 int32_t android_atomic_dec(volatile int32_t *addr)
128 {
129 return android_atomic_add(-1, addr);
130 }
131
132 extern ANDROID_ATOMIC_INLINE
android_atomic_and(int32_t value,volatile int32_t * ptr)133 int32_t android_atomic_and(int32_t value, volatile int32_t *ptr)
134 {
135 int32_t prev, status;
136 android_memory_barrier();
137 do {
138 prev = *ptr;
139 status = android_atomic_cas(prev, prev & value, ptr);
140 } while (__builtin_expect(status != 0, 0));
141 return prev;
142 }
143
144 extern ANDROID_ATOMIC_INLINE
android_atomic_or(int32_t value,volatile int32_t * ptr)145 int32_t android_atomic_or(int32_t value, volatile int32_t *ptr)
146 {
147 int32_t prev, status;
148 android_memory_barrier();
149 do {
150 prev = *ptr;
151 status = android_atomic_cas(prev, prev | value, ptr);
152 } while (__builtin_expect(status != 0, 0));
153 return prev;
154 }
155
156 #endif /* ANDROID_CUTILS_ATOMIC_AARCH64_H */
157