| /* |
| * Copyright (c) 2012, 2015, 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 |
| * 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. |
| */ |
| |
| /* |
| * @test |
| * @bug 7196045 |
| * @bug 8014294 |
| * @summary Possible JVM deadlock in ThreadTimesClosure when using HotspotInternal non-public API. |
| * @modules java.management/sun.management |
| * @run main/othervm -XX:+UsePerfData -Xmx32m ThreadCpuTimesDeadlock |
| */ |
| |
| import java.lang.management.ManagementFactory; |
| import javax.management.JMException; |
| import javax.management.MBeanServer; |
| import javax.management.MalformedObjectNameException; |
| import javax.management.ObjectName; |
| |
| public class ThreadCpuTimesDeadlock { |
| |
| public static byte[] dummy; |
| public static long duration = 10 * 1000; |
| private static final String HOTSPOT_INTERNAL = "sun.management:type=HotspotInternal"; |
| |
| public static void main(String[] args) { |
| |
| MBeanServer server = ManagementFactory.getPlatformMBeanServer(); |
| ObjectName objName= null; |
| try { |
| ObjectName hotspotInternal = new ObjectName(HOTSPOT_INTERNAL); |
| try { |
| server.registerMBean(new sun.management.HotspotInternal(), hotspotInternal); |
| } catch (JMException e) { |
| throw new RuntimeException("HotSpotWatcher: Failed to register the HotspotInternal MBean" + e); |
| } |
| objName= new ObjectName("sun.management:type=HotspotThreading"); |
| |
| } catch (MalformedObjectNameException e1) { |
| throw new RuntimeException("Bad object name" + e1); |
| } |
| |
| // Thread that allocs memory to generate GC's |
| Thread allocThread = new Thread() { |
| public void run() { |
| while (true) { |
| dummy = new byte[4096]; |
| } |
| } |
| }; |
| |
| allocThread.setDaemon(true); |
| allocThread.start(); |
| |
| long endTime = System.currentTimeMillis() + duration; |
| long i = 0; |
| while (true) { |
| try { |
| server.getAttribute(objName, "InternalThreadCpuTimes"); |
| } catch (Exception ex) { |
| System.err.println("Exception while getting attribute: " + ex); |
| } |
| i++; |
| if (i % 10000 == 0) { |
| System.out.println("Successful iterations: " + i); |
| } |
| if (System.currentTimeMillis() > endTime) { |
| break; |
| } |
| } |
| System.out.println("PASSED."); |
| } |
| } |