1 /* 2 * @(#)AdaptiveFreeList.java 3 * 4 * Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved. 5 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 6 * 7 * This code is free software; you can redistribute it and/or modify it 8 * under the terms of the GNU General Public License version 2 only, as 9 * published by the Free Software Foundation. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 * 25 */ 26 27 package sun.jvm.hotspot.gc.cms; 28 29 import java.util.Observable; 30 import java.util.Observer; 31 32 import sun.jvm.hotspot.debugger.Address; 33 import sun.jvm.hotspot.runtime.VM; 34 import sun.jvm.hotspot.runtime.VMObject; 35 import sun.jvm.hotspot.types.CIntegerField; 36 import sun.jvm.hotspot.types.Type; 37 import sun.jvm.hotspot.types.TypeDataBase; 38 39 public class AdaptiveFreeList extends VMObject { 40 static { VM.registerVMInitializedObserver(new Observer() { public void update(Observable o, Object data) { initialize(VM.getVM().getTypeDataBase()); } })41 VM.registerVMInitializedObserver(new Observer() { 42 public void update(Observable o, Object data) { 43 initialize(VM.getVM().getTypeDataBase()); 44 } 45 }); 46 } 47 initialize(TypeDataBase db)48 private static synchronized void initialize(TypeDataBase db) { 49 Type type = db.lookupType("AdaptiveFreeList<FreeChunk>"); 50 sizeField = type.getCIntegerField("_size"); 51 countField = type.getCIntegerField("_count"); 52 headerSize = type.getSize(); 53 } 54 55 // Fields 56 private static CIntegerField sizeField; 57 private static CIntegerField countField; 58 private static long headerSize; 59 60 //Constructor AdaptiveFreeList(Address address)61 public AdaptiveFreeList(Address address) { 62 super(address); 63 } 64 65 // Accessors size()66 public long size() { 67 return sizeField.getValue(addr); 68 } 69 count()70 public long count() { 71 return countField.getValue(addr); 72 } 73 sizeOf()74 public static long sizeOf() { 75 return headerSize; 76 } 77 } 78