1 /*
   2  * Copyright (c) 2012, 2014, 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.hotspot;
  26 
  27 import java.lang.reflect.Executable;
  28 import java.util.Arrays;
  29 import java.util.List;
  30 import java.util.function.Function;
  31 import java.util.stream.Stream;
  32 import java.security.BasicPermission;
  33 import sun.hotspot.parser.DiagnosticCommand;
  34 
  35 public class WhiteBox {
  36 
  37   @SuppressWarnings("serial")
  38   public static class WhiteBoxPermission extends BasicPermission {
  39     public WhiteBoxPermission(String s) {
  40       super(s);
  41     }
  42   }
  43 
  44   private WhiteBox() {}
  45   private static final WhiteBox instance = new WhiteBox();
  46   private static native void registerNatives();
  47 
  48   /**
  49    * Returns the singleton WhiteBox instance.
  50    *
  51    * The returned WhiteBox object should be carefully guarded
  52    * by the caller, since it can be used to read and write data
  53    * at arbitrary memory addresses. It must never be passed to
  54    * untrusted code.
  55    */
  56   public synchronized static WhiteBox getWhiteBox() {
  57     SecurityManager sm = System.getSecurityManager();
  58     if (sm != null) {
  59       sm.checkPermission(new WhiteBoxPermission("getInstance"));
  60     }
  61     return instance;
  62   }
  63 
  64   static {
  65     registerNatives();
  66   }
  67 
  68   // Get the maximum heap size supporting COOPs
  69   public native long getCompressedOopsMaxHeapSize();
  70   // Arguments
  71   public native void printHeapSizes();
  72 
  73   // Memory
  74   public native long getObjectAddress(Object o);
  75   public native int  getHeapOopSize();
  76 
  77   // Runtime
  78   // Make sure class name is in the correct format
  79   public boolean isClassAlive(String name) {
  80     return isClassAlive0(name.replace('.', '/'));
  81   }
  82   private native boolean isClassAlive0(String name);
  83 
  84   // G1
  85   public native boolean g1InConcurrentMark();
  86   public native boolean g1IsHumongous(Object o);
  87   public native long    g1NumFreeRegions();
  88   public native int     g1RegionSize();
  89   public native Object[]    parseCommandLine(String commandline, DiagnosticCommand[] args);
  90 
  91   // NMT
  92   public native long NMTMalloc(long size);
  93   public native void NMTFree(long mem);
  94   public native long NMTReserveMemory(long size);
  95   public native void NMTCommitMemory(long addr, long size);
  96   public native void NMTUncommitMemory(long addr, long size);
  97   public native void NMTReleaseMemory(long addr, long size);
  98   public native void NMTOverflowHashBucket(long num);
  99   public native long NMTMallocWithPseudoStack(long size, int index);
 100   public native boolean NMTIsDetailSupported();
 101 
 102   // Compiler
 103   public native void    deoptimizeAll();
 104   public        boolean isMethodCompiled(Executable method) {
 105     return isMethodCompiled(method, false /*not osr*/);
 106   }
 107   public native boolean isMethodCompiled(Executable method, boolean isOsr);
 108   public        boolean isMethodCompilable(Executable method) {
 109     return isMethodCompilable(method, -1 /*any*/);
 110   }
 111   public        boolean isMethodCompilable(Executable method, int compLevel) {
 112     return isMethodCompilable(method, compLevel, false /*not osr*/);
 113   }
 114   public native boolean isMethodCompilable(Executable method, int compLevel, boolean isOsr);
 115   public native boolean isMethodQueuedForCompilation(Executable method);
 116   public        int     deoptimizeMethod(Executable method) {
 117     return deoptimizeMethod(method, false /*not osr*/);
 118   }
 119   public native int     deoptimizeMethod(Executable method, boolean isOsr);
 120   public        void    makeMethodNotCompilable(Executable method) {
 121     makeMethodNotCompilable(method, -1 /*any*/);
 122   }
 123   public        void    makeMethodNotCompilable(Executable method, int compLevel) {
 124     makeMethodNotCompilable(method, compLevel, false /*not osr*/);
 125   }
 126   public native void    makeMethodNotCompilable(Executable method, int compLevel, boolean isOsr);
 127   public        int     getMethodCompilationLevel(Executable method) {
 128     return getMethodCompilationLevel(method, false /*not ost*/);
 129   }
 130   public native int     getMethodCompilationLevel(Executable method, boolean isOsr);
 131   public native boolean testSetDontInlineMethod(Executable method, boolean value);
 132   public        int     getCompileQueuesSize() {
 133     return getCompileQueueSize(-1 /*any*/);
 134   }
 135   public native int     getCompileQueueSize(int compLevel);
 136   public native boolean testSetForceInlineMethod(Executable method, boolean value);
 137   public        boolean enqueueMethodForCompilation(Executable method, int compLevel) {
 138     return enqueueMethodForCompilation(method, compLevel, -1 /*InvocationEntryBci*/);
 139   }
 140   public native boolean enqueueMethodForCompilation(Executable method, int compLevel, int entry_bci);
 141   public native void    clearMethodState(Executable method);
 142   public native int     getMethodEntryBci(Executable method);
 143   public native Object[] getNMethod(Executable method, boolean isOsr);
 144 
 145   // Intered strings
 146   public native boolean isInStringTable(String str);
 147 
 148   // Memory
 149   public native void readReservedMemory();
 150   public native long allocateMetaspace(ClassLoader classLoader, long size);
 151   public native void freeMetaspace(ClassLoader classLoader, long addr, long size);
 152 
 153   // force Full GC
 154   public native void fullGC();
 155 
 156   // Tests on ReservedSpace/VirtualSpace classes
 157   public native int stressVirtualSpaceResize(long reservedSpaceSize, long magnitude, long iterations);
 158   public native void runMemoryUnitTests();
 159   public native void readFromNoaccessArea();
 160   public native long getThreadStackSize();
 161   public native long getThreadRemainingStackSize();
 162 
 163   // CPU features
 164   public native String getCPUFeatures();
 165 
 166   // VM flags
 167   public native void    setBooleanVMFlag(String name, boolean value);
 168   public native void    setIntxVMFlag(String name, long value);
 169   public native void    setUintxVMFlag(String name, long value);
 170   public native void    setUint64VMFlag(String name, long value);
 171   public native void    setStringVMFlag(String name, String value);
 172   public native void    setDoubleVMFlag(String name, double value);
 173   public native Boolean getBooleanVMFlag(String name);
 174   public native Long    getIntxVMFlag(String name);
 175   public native Long    getUintxVMFlag(String name);
 176   public native Long    getUint64VMFlag(String name);
 177   public native String  getStringVMFlag(String name);
 178   public native Double  getDoubleVMFlag(String name);
 179   private final List<Function<String,Object>> flagsGetters = Arrays.asList(
 180     this::getBooleanVMFlag, this::getIntxVMFlag, this::getUintxVMFlag,
 181     this::getUint64VMFlag, this::getStringVMFlag, this::getDoubleVMFlag);
 182 
 183   public Object getVMFlag(String name) {
 184     return flagsGetters.stream()
 185                        .map(f -> f.apply(name))
 186                        .filter(x -> x != null)
 187                        .findAny()
 188                        .orElse(null);
 189   }
 190 }