2 * Copyright (C) 2008 The Android Open Source Project
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
20 #ifndef DALVIK_ATOMIC_H_
21 #define DALVIK_ATOMIC_H_
23 #include <cutils/atomic.h> /* use common Android atomic ops */
24 #include <cutils/atomic-inline.h> /* and some uncommon ones */
26 void dvmQuasiAtomicsStartup();
27 void dvmQuasiAtomicsShutdown();
30 * NOTE: Two "quasiatomic" operations on the exact same memory address
31 * are guaranteed to operate atomically with respect to each other,
32 * but no guarantees are made about quasiatomic operations mixed with
33 * non-quasiatomic operations on the same address, nor about
34 * quasiatomic operations that are performed on partially-overlapping
37 * Only the "Sync" versions of these provide a memory barrier.
41 * Swap the 64-bit value at "addr" with "value". Returns the previous
44 extern "C" int64_t dvmQuasiAtomicSwap64(int64_t value, volatile int64_t* addr);
47 * Swap the 64-bit value at "addr" with "value". Returns the previous
48 * value. Provides memory barriers.
50 extern "C" int64_t dvmQuasiAtomicSwap64Sync(int64_t value,
51 volatile int64_t* addr);
54 * Read the 64-bit value at "addr".
56 extern "C" int64_t dvmQuasiAtomicRead64(volatile const int64_t* addr);
59 * If the value at "addr" is equal to "oldvalue", replace it with "newvalue"
60 * and return 0. Otherwise, don't swap, and return nonzero.
62 int dvmQuasiAtomicCas64(int64_t oldvalue, int64_t newvalue,
63 volatile int64_t* addr);
65 #endif // DALVIK_ATOMIC_H_