| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more contributor license |
| * agreements. See the NOTICE file distributed with this work for additional information regarding |
| * copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance with the License. You may obtain a |
| * copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software distributed under the License |
| * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express |
| * or implied. See the License for the specific language governing permissions and limitations under |
| * the License. |
| */ |
| package org.apache.geode.internal.offheap; |
| |
| import java.util.concurrent.atomic.AtomicIntegerFieldUpdater; |
| |
| /** |
| * A fragment is a block of memory that can have chunks allocated from it. The allocations are |
| * always from the front so the free memory is always at the end. The freeIdx keeps track of the |
| * first byte of free memory in the fragment. The base memory address and the total size of a |
| * fragment never change. During defragmentation fragments go away and are recreated. |
| * |
| * |
| */ |
| public class Fragment implements MemoryBlock { |
| private static final byte FILL_BYTE = OffHeapStoredObject.FILL_BYTE; |
| private final long baseAddr; |
| private final int size; |
| @SuppressWarnings("unused") |
| private volatile int freeIdx; |
| private static final AtomicIntegerFieldUpdater<Fragment> freeIdxUpdater = |
| AtomicIntegerFieldUpdater.newUpdater(Fragment.class, "freeIdx"); |
| |
| public Fragment(long addr, int size) { |
| MemoryAllocatorImpl.validateAddress(addr); |
| this.baseAddr = addr; |
| this.size = size; |
| freeIdxUpdater.set(this, 0); |
| } |
| |
| public int freeSpace() { |
| return getSize() - getFreeIndex(); |
| } |
| |
| public boolean allocate(int oldOffset, int newOffset) { |
| return freeIdxUpdater.compareAndSet(this, oldOffset, newOffset); |
| } |
| |
| public int getFreeIndex() { |
| return freeIdxUpdater.get(this); |
| } |
| |
| public int getSize() { |
| return this.size; |
| } |
| |
| @Override |
| public long getAddress() { |
| return this.baseAddr; |
| } |
| |
| @Override |
| public State getState() { |
| return State.UNUSED; |
| } |
| |
| @Override |
| public MemoryBlock getNextBlock() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| @Override |
| public int getBlockSize() { |
| return freeSpace(); |
| } |
| |
| @Override |
| public int getSlabId() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| @Override |
| public int getFreeListId() { |
| return -1; |
| } |
| |
| @Override |
| public int getRefCount() { |
| return 0; |
| } |
| |
| @Override |
| public String getDataType() { |
| return "N/A"; |
| } |
| |
| @Override |
| public boolean isSerialized() { |
| return false; |
| } |
| |
| @Override |
| public boolean isCompressed() { |
| return false; |
| } |
| |
| @Override |
| public Object getDataValue() { |
| return null; |
| } |
| |
| public void fill() { |
| AddressableMemoryManager.fill(this.baseAddr, this.size, FILL_BYTE); |
| } |
| |
| @Override |
| public boolean equals(Object o) { |
| if (o instanceof Fragment) { |
| return getAddress() == ((Fragment) o).getAddress(); |
| } |
| return false; |
| } |
| |
| @Override |
| public int hashCode() { |
| long value = this.getAddress(); |
| return (int) (value ^ (value >>> 32)); |
| } |
| |
| @Override |
| public String toString() { |
| return "Fragment [baseAddr=" + baseAddr + ", size=" + size + ", freeIdx=" + freeIdx + "]"; |
| } |
| |
| } |