1 /* 2 * Copyright (c) 2011, 2019, 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.io.PrintStream; 28 import java.util.ArrayList; 29 import java.util.List; 30 import java.util.Observable; 31 import java.util.Observer; 32 import sun.jvm.hotspot.debugger.Address; 33 import sun.jvm.hotspot.debugger.OopHandle; 34 import sun.jvm.hotspot.gc.shared.CompactibleSpace; 35 import sun.jvm.hotspot.gc.shared.LiveRegionsProvider; 36 import sun.jvm.hotspot.memory.MemRegion; 37 import sun.jvm.hotspot.runtime.VM; 38 import sun.jvm.hotspot.runtime.VMObjectFactory; 39 import sun.jvm.hotspot.types.AddressField; 40 import sun.jvm.hotspot.types.CIntegerField; 41 import sun.jvm.hotspot.types.Type; 42 import sun.jvm.hotspot.types.TypeDataBase; 43 44 // Mirror class for HeapRegion. Currently we don't actually include 45 // any of its fields but only iterate over it. 46 47 public class HeapRegion extends CompactibleSpace implements LiveRegionsProvider { 48 private static AddressField bottomField; 49 static private AddressField topField; 50 private static AddressField endField; 51 52 static private CIntegerField grainBytesField; 53 private static long typeFieldOffset; 54 private static long pointerSize; 55 56 private HeapRegionType type; 57 58 static { 59 VM.registerVMInitializedObserver(new Observer() { 60 public void update(Observable o, Object data) { 61 initialize(VM.getVM().getTypeDataBase()); 62 } 63 }); 64 } 65 66 static private synchronized void initialize(TypeDataBase db) { 67 Type type = db.lookupType("HeapRegion"); 68 69 bottomField = type.getAddressField("_bottom"); 70 topField = type.getAddressField("_top"); 71 endField = type.getAddressField("_end"); 72 73 grainBytesField = type.getCIntegerField("GrainBytes"); 74 typeFieldOffset = type.getField("_type").getOffset(); 75 76 pointerSize = db.lookupType("HeapRegion*").getSize(); 77 } 78 79 static public long grainBytes() { 80 return grainBytesField.getValue(); 81 } 82 83 public HeapRegion(Address addr) { 84 super(addr); 85 Address typeAddr = (addr instanceof OopHandle) ? addr.addOffsetToAsOopHandle(typeFieldOffset) 86 : addr.addOffsetTo(typeFieldOffset); 87 type = (HeapRegionType)VMObjectFactory.newObject(HeapRegionType.class, typeAddr); 88 } 89 90 public Address bottom() { return bottomField.getValue(addr); } 91 public Address top() { return topField.getValue(addr); } 92 public Address end() { return endField.getValue(addr); } 93 94 @Override 95 public List<MemRegion> getLiveRegions() { 96 List<MemRegion> res = new ArrayList<>(); 97 res.add(new MemRegion(bottom(), top())); 98 return res; 99 } 100 101 /** Returns a subregion of the space containing all the objects in 102 the space. */ 103 public MemRegion usedRegion() { 104 return new MemRegion(bottom(), end()); 105 } 106 107 public long used() { 108 return top().minus(bottom()); 109 } 110 111 public long free() { 112 return end().minus(top()); 113 } 114 115 public boolean isFree() { 116 return type.isFree(); 117 } 118 119 public boolean isYoung() { 120 return type.isYoung(); 121 } 122 123 public boolean isHumongous() { 124 return type.isHumongous(); 125 } 126 127 public boolean isPinned() { 128 return type.isPinned(); 129 } 130 131 public boolean isOld() { 132 return type.isOld(); 133 } 134 135 public static long getPointerSize() { 136 return pointerSize; 137 } 138 139 public void printOn(PrintStream tty) { 140 tty.print("Region: " + bottom() + "," + top() + "," + end()); 141 tty.println(":" + type.typeAnnotation()); 142 } 143 }