atomic-inline.h revision 93b0cb40c18cae594c931677be2b9214420610b7 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef ANDROID_CUTILS_ATOMIC_INLINE_H
18#define ANDROID_CUTILS_ATOMIC_INLINE_H
19
20/*
21 * Inline declarations and macros for some special-purpose atomic
22 * operations.  These are intended for rare circumstances where a
23 * memory barrier needs to be issued inline rather than as a function
24 * call.
25 *
26 * Most code should not use these.
27 *
28 * Anything that does include this file must set ANDROID_SMP to either
29 * 0 or 1, indicating compilation for UP or SMP, respectively.
30 *
31 * Macros defined in this header:
32 *
33 * void ANDROID_MEMBAR_FULL(void)
34 *   Full memory barrier.  Provides a compiler reordering barrier, and
35 *   on SMP systems emits an appropriate instruction.
36 */
37
38#if !defined(ANDROID_SMP)
39# error "Must define ANDROID_SMP before including atomic-inline.h"
40#endif
41
42#if defined(__arm__)
43#include <cutils/atomic-arm.h>
44#elif defined(__i386__) || defined(__x86_64__)
45#include <cutils/atomic-x86.h>
46#elif defined(__sh__)
47/* implementation is in atomic-android-sh.c */
48#else
49#error atomic operations are unsupported
50#endif
51
52#if ANDROID_SMP == 0
53#define ANDROID_MEMBAR_FULL android_compiler_barrier
54#else
55#define ANDROID_MEMBAR_FULL android_memory_barrier
56#endif
57
58#endif /* ANDROID_CUTILS_ATOMIC_INLINE_H */
59