1 /* 2 * Copyright (c) 2011, 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 package sun.jvm.hotspot.gc.g1; 26 27 import java.util.ArrayList; 28 import java.util.List; 29 import java.util.Observable; 30 import java.util.Observer; 31 import sun.jvm.hotspot.debugger.Address; 32 import sun.jvm.hotspot.memory.CompactibleSpace; 33 import sun.jvm.hotspot.memory.MemRegion; 34 import sun.jvm.hotspot.runtime.VM; 35 import sun.jvm.hotspot.types.AddressField; 36 import sun.jvm.hotspot.types.CIntegerField; 37 import sun.jvm.hotspot.types.Type; 38 import sun.jvm.hotspot.types.TypeDataBase; 39 40 // Mirror class for HeapRegion. Currently we don't actually include 41 // any of its fields but only iterate over it. 42 43 public class HeapRegion extends CompactibleSpace { 44 // static int GrainBytes; 45 static private CIntegerField grainBytesField; 46 static private AddressField topField; 47 48 static { 49 VM.registerVMInitializedObserver(new Observer() { 50 public void update(Observable o, Object data) { 51 initialize(VM.getVM().getTypeDataBase()); 52 } 53 }); 54 } 55 56 static private synchronized void initialize(TypeDataBase db) { 57 Type type = db.lookupType("HeapRegion"); 58 59 grainBytesField = type.getCIntegerField("GrainBytes"); 60 topField = type.getAddressField("_top"); 61 62 } 63 64 static public long grainBytes() { 65 return grainBytesField.getValue(); 66 } 67 68 public HeapRegion(Address addr) { 69 super(addr); 70 } 71 72 public Address top() { 73 return topField.getValue(addr); 74 } 75 76 @Override 77 public List getLiveRegions() { 78 List res = new ArrayList(); 79 res.add(new MemRegion(bottom(), top())); 80 return res; 81 } 82 83 @Override 84 public long used() { 85 return top().minus(bottom()); 86 } 87 88 @Override 89 public long free() { 90 return end().minus(top()); 91 } 92 }