8036666: VMTI GetObjectMonitorUsage does not return correct recursion count
Summary: fix object lock recursion count and add test
Reviewed-by: sspitsyn, dsamersoff
--- a/hotspot/src/share/vm/prims/jvmtiEnvBase.cpp Fri Mar 28 21:04:37 2014 -0700
+++ b/hotspot/src/share/vm/prims/jvmtiEnvBase.cpp Tue Mar 11 15:22:44 2014 +0100
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2014, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -1020,19 +1020,12 @@
}
if (owning_thread != NULL) { // monitor is owned
- if ((address)owning_thread == owner) {
- // the owner field is the JavaThread *
- assert(mon != NULL,
- "must have heavyweight monitor with JavaThread * owner");
- ret.entry_count = mon->recursions() + 1;
- } else {
- // The owner field is the Lock word on the JavaThread's stack
- // so the recursions field is not valid. We have to count the
- // number of recursive monitor entries the hard way. We pass
- // a handle to survive any GCs along the way.
- ResourceMark rm;
- ret.entry_count = count_locked_objects(owning_thread, hobj);
- }
+ // The recursions field of a monitor does not reflect recursions
+ // as lightweight locks before inflating the monitor are not included.
+ // We have to count the number of recursive monitor entries the hard way.
+ // We pass a handle to survive any GCs along the way.
+ ResourceMark rm;
+ ret.entry_count = count_locked_objects(owning_thread, hobj);
}
// implied else: entry_count == 0
}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/serviceability/jvmti/8036666/GetObjectLockCount.java Tue Mar 11 15:22:44 2014 +0100
@@ -0,0 +1,284 @@
+/*
+ * Copyright 2014 SAP AG. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+
+import com.sun.jdi.AbsentInformationException;
+import com.sun.jdi.Bootstrap;
+import com.sun.jdi.LocalVariable;
+import com.sun.jdi.Location;
+import com.sun.jdi.ObjectReference;
+import com.sun.jdi.ReferenceType;
+import com.sun.jdi.StackFrame;
+import com.sun.jdi.ThreadReference;
+import com.sun.jdi.Value;
+import com.sun.jdi.VirtualMachine;
+import com.sun.jdi.connect.Connector;
+import com.sun.jdi.connect.Connector.Argument;
+import com.sun.jdi.connect.IllegalConnectorArgumentsException;
+import com.sun.jdi.connect.LaunchingConnector;
+import com.sun.jdi.connect.VMStartException;
+import com.sun.jdi.event.BreakpointEvent;
+import com.sun.jdi.event.ClassPrepareEvent;
+import com.sun.jdi.event.Event;
+import com.sun.jdi.event.EventQueue;
+import com.sun.jdi.event.EventSet;
+import com.sun.jdi.event.VMDeathEvent;
+import com.sun.jdi.event.VMDisconnectEvent;
+import com.sun.jdi.event.VMStartEvent;
+import com.sun.jdi.request.BreakpointRequest;
+import com.sun.jdi.request.ClassPrepareRequest;
+import com.sun.jdi.request.EventRequestManager;
+
+
+/*
+ * @test GetObjectLockCount.java
+ * @bug 8036666
+ * @key regression
+ * @summary verify jvm returns correct lock recursion count
+ * @run compile -g RecursiveObjectLock.java
+ * @run main/othervm GetObjectLockCount
+ * @author axel.siebenborn@sap.com
+ */
+
+public class GetObjectLockCount {
+
+ public static final String CLASS_NAME = "RecursiveObjectLock";
+ public static final String METHOD_NAME = "breakpoint1";
+ public static final String ARGUMENTS = "";
+
+
+ /**
+ * Find a com.sun.jdi.CommandLineLaunch connector
+ */
+ static LaunchingConnector findLaunchingConnector() {
+ List <Connector> connectors = Bootstrap.virtualMachineManager().allConnectors();
+ Iterator <Connector> iter = connectors.iterator();
+ while (iter.hasNext()) {
+ Connector connector = iter.next();
+ if (connector.name().equals("com.sun.jdi.CommandLineLaunch")) {
+ return (LaunchingConnector)connector;
+ }
+ }
+ throw new Error("No launching connector");
+ }
+
+ static VirtualMachine launchTarget(String mainArgs) {
+ LaunchingConnector connector = findLaunchingConnector();
+ Map<String, Argument> arguments = connectorArguments(connector, mainArgs);
+ try {
+ return (VirtualMachine) connector.launch(arguments);
+ } catch (IOException exc) {
+ throw new Error("Unable to launch target VM: " + exc);
+ } catch (IllegalConnectorArgumentsException exc) {
+ throw new Error("Internal error: " + exc);
+ } catch (VMStartException exc) {
+ throw new Error("Target VM failed to initialize: " +
+ exc.getMessage());
+ }
+ }
+ /**
+ * Return the launching connector's arguments.
+ */
+ static Map <String,Connector.Argument> connectorArguments(LaunchingConnector connector, String mainArgs) {
+ Map<String,Connector.Argument> arguments = connector.defaultArguments();
+
+ Connector.Argument mainArg = (Connector.Argument)arguments.get("main");
+ if (mainArg == null) {
+ throw new Error("Bad launching connector");
+ }
+ mainArg.setValue(mainArgs);
+
+ Connector.Argument optionsArg = (Connector.Argument)arguments.get("options");
+ if (optionsArg == null) {
+ throw new Error("Bad launching connector");
+ }
+ optionsArg.setValue(ARGUMENTS);
+ return arguments;
+ }
+
+ private static void addClassWatch(VirtualMachine vm) {
+ EventRequestManager erm = vm.eventRequestManager();
+ ClassPrepareRequest classPrepareRequest = erm
+ .createClassPrepareRequest();
+ classPrepareRequest.addClassFilter(CLASS_NAME);
+ classPrepareRequest.setEnabled(true);
+ }
+
+ private static void addBreakpoint(VirtualMachine vm, ReferenceType refType) {
+ Location breakpointLocation = null;
+ List<Location> locs;
+ try {
+ locs = refType.allLineLocations();
+ for (Location loc: locs) {
+ if (loc.method().name().equals(METHOD_NAME)) {
+ breakpointLocation = loc;
+ break;
+ }
+ }
+ } catch (AbsentInformationException e) {
+ // TODO Auto-generated catch block
+ e.printStackTrace();
+ }
+ if (breakpointLocation != null) {
+ EventRequestManager evtReqMgr = vm.eventRequestManager();
+ BreakpointRequest bReq = evtReqMgr.createBreakpointRequest(breakpointLocation);
+ bReq.setSuspendPolicy(BreakpointRequest.SUSPEND_ALL);
+ bReq.enable();
+ }
+ }
+
+ /**
+ * @param args
+ * @throws InterruptedException
+ */
+ public static void main(String[] args) throws InterruptedException {
+
+ VirtualMachine vm = launchTarget(CLASS_NAME);
+
+ // process events
+ EventQueue eventQueue = vm.eventQueue();
+ // resume the vm
+ boolean launched = false;
+
+ while (!launched) {
+ EventSet eventSet = eventQueue.remove();
+ for (Event event : eventSet) {
+ if (event instanceof VMStartEvent) {
+ System.out.println("Vm launched");
+ // set watch field on already loaded classes
+ List<ReferenceType> referenceTypes = vm.classesByName(CLASS_NAME);
+ for (ReferenceType refType : referenceTypes) {
+ System.out.println("Found Class");
+ addBreakpoint(vm, refType);
+ }
+
+ // watch for loaded classes
+ addClassWatch(vm);
+ vm.resume();
+ launched = true;
+ }
+ }
+ }
+
+ Process process = vm.process();
+
+ // Copy target's output and error to our output and error.
+ Thread outThread = new StreamRedirectThread("out reader", process.getInputStream());
+ Thread errThread = new StreamRedirectThread("error reader", process.getErrorStream());
+
+ int recursionCount = -1;
+
+ errThread.start();
+ outThread.start();
+ boolean connected = true;
+ while (connected) {
+ EventSet eventSet = eventQueue.remove();
+ for (Event event : eventSet) {
+ if (event instanceof VMDeathEvent || event instanceof VMDisconnectEvent) {
+ // exit
+ connected = false;
+ }
+ else if (event instanceof ClassPrepareEvent) {
+ // watch field on loaded class
+ System.out.println("ClassPrepareEvent");
+ ClassPrepareEvent classPrepEvent = (ClassPrepareEvent) event;
+ ReferenceType refType = classPrepEvent.referenceType();
+ addBreakpoint(vm, refType);
+ } else if (event instanceof BreakpointEvent) {
+ recursionCount = getLockRecursions(vm);
+ System.out.println("resume...");
+ }
+ }
+ eventSet.resume();
+ }
+ // Shutdown begins when event thread terminates
+ try {
+ errThread.join(); // Make sure output is forwarded
+ outThread.join();
+ } catch (InterruptedException e) {
+ // we don't interrupt
+ e.printStackTrace();
+ }
+ if (recursionCount != 3) {
+ throw new AssertionError("recursions: expected 3, but was " + recursionCount);
+ }
+ }
+
+ public static int getLockRecursions(VirtualMachine vm) {
+ List <ThreadReference> threads = vm.allThreads();
+ for (ThreadReference thread : threads) {
+ if (thread.name().equals("main")) {
+
+ System.out.println("Found main thread.");
+ try{
+ StackFrame frame = thread.frame(3);
+ return frame.thisObject().entryCount();
+ } catch (Exception e) {
+ e.printStackTrace();
+ }
+ }
+ System.out.println("Main thread not found!");
+ }
+ return -1;
+ }
+}
+
+class StreamRedirectThread extends Thread {
+
+ private final BufferedReader in;
+
+ private static final int BUFFER_SIZE = 2048;
+
+ /**
+ * Set up for copy.
+ * @param name Name of the thread
+ * @param in Stream to copy from
+ */
+ StreamRedirectThread(String name, InputStream in) {
+ super(name);
+ this.in = new BufferedReader(new InputStreamReader(in));
+ }
+
+ /**
+ * Copy.
+ */
+ public void run() {
+ try {
+ String line;
+ while ((line = in.readLine ()) != null) {
+ System.out.println("testvm: " + line);
+ }
+ System.out.flush();
+ } catch(IOException exc) {
+ System.err.println("Child I/O Transfer - " + exc);
+ exc.printStackTrace();
+ }
+ }
+}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/serviceability/jvmti/8036666/RecursiveObjectLock.java Tue Mar 11 15:22:44 2014 +0100
@@ -0,0 +1,63 @@
+/*
+ * Copyright 2014 SAP AG. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+public class RecursiveObjectLock {
+
+ public void testMethod() {
+ synchronized (this) {
+ nestedLock1();
+ }
+ }
+
+ public void nestedLock1() {
+ synchronized (this) {
+ nestedLock2();
+ }
+ }
+
+ public void nestedLock2() {
+ synchronized (this) {
+ callWait();
+ }
+ }
+
+ public void callWait(){
+ try {
+ this.wait(1);
+ } catch (InterruptedException e) {
+ e.printStackTrace();
+ }
+ breakpoint1();
+ }
+
+ public static void breakpoint1() {
+ // purpose: hold a breakpoint
+ }
+
+ public static void main(String[] args) {
+ RecursiveObjectLock ro = new RecursiveObjectLock();
+ ro.testMethod();
+ System.out.println("ready");
+ }
+
+}