cutils/atomic-inline.h

   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 #ifdef __cplusplus
  21 extern "C" {
  22 #endif
  23
  24 /*
  25  * Inline declarations and macros for some special-purpose atomic
  26  * operations.  These are intended for rare circumstances where a
  27  * memory barrier needs to be issued inline rather than as a function
  28  * call.
  29  *
  30  * Most code should not use these.
  31  *
  32  * Anything that does include this file must set ANDROID_SMP to either
  33  * 0 or 1, indicating compilation for UP or SMP, respectively.
  34  *
  35  * Macros defined in this header:
  36  *
  37  * void ANDROID_MEMBAR_FULL(void)
  38  *   Full memory barrier.  Provides a compiler reordering barrier, and
  39  *   on SMP systems emits an appropriate instruction.
  40  */
  41
  42 #if !defined(ANDROID_SMP)
  43 # error "Must define ANDROID_SMP before including atomic-inline.h"
  44 #endif
  45
  46 #if defined(__arm__)
  47 #include <cutils/atomic-arm.h>
  48 #elif defined(__i386__) || defined(__x86_64__)
  49 #include <cutils/atomic-x86.h>
  50 #elif defined(__mips__)
  51 #include <cutils/atomic-mips.h>
  52 #else
  53 #error atomic operations are unsupported
  54 #endif
  55
  56 #if ANDROID_SMP == 0
  57 #define ANDROID_MEMBAR_FULL android_compiler_barrier
  58 #else
  59 #define ANDROID_MEMBAR_FULL android_memory_barrier
  60 #endif
  61
  62 #if ANDROID_SMP == 0
  63 #define ANDROID_MEMBAR_STORE android_compiler_barrier
  64 #else
  65 #define ANDROID_MEMBAR_STORE android_memory_store_barrier
  66 #endif
  67
  68 #ifdef __cplusplus
  69 }
  70 #endif
  71
  72 #endif /* ANDROID_CUTILS_ATOMIC_INLINE_H */