1 /*
   2  * Copyright (c) 2020, 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 package runtime.whitebox;
  25 
  26 /*
  27  * @test TestWBDeflateIdleMonitors
  28  * @bug 8246477
  29  * @summary Test verify that WB method deflateIdleMonitors works correctly.
  30  * @library /test/lib
  31  * @modules java.base/jdk.internal.misc
  32  *          java.management
  33  * @build sun.hotspot.WhiteBox
  34  * @run driver ClassFileInstaller sun.hotspot.WhiteBox
  35  * @run driver runtime.whitebox.TestWBDeflateIdleMonitors
  36  */
  37 import jdk.test.lib.Asserts;
  38 import jdk.test.lib.process.ProcessTools;
  39 import jdk.test.lib.process.OutputAnalyzer;
  40 import sun.hotspot.WhiteBox;
  41 
  42 public class TestWBDeflateIdleMonitors {
  43 
  44     public static void main(String args[]) throws Exception {
  45         ProcessBuilder pb = ProcessTools.createTestJvm(
  46                 "-Xbootclasspath/a:.",
  47                 "-XX:+UnlockDiagnosticVMOptions",
  48                 "-XX:+WhiteBoxAPI",
  49                 "-Xlog:monitorinflation=info",
  50                 InflateMonitorsTest.class.getName());
  51 
  52         OutputAnalyzer output = new OutputAnalyzer(pb.start());
  53         System.out.println(output.getStdout());
  54         output.shouldHaveExitValue(0);
  55         output.shouldContain("WhiteBox initiated DeflateIdleMonitors");
  56     }
  57 
  58     public static class InflateMonitorsTest {
  59         static WhiteBox wb = WhiteBox.getWhiteBox();
  60         public static Object obj;
  61 
  62         public static void main(String args[]) {
  63             obj = new Object();
  64             synchronized (obj) {
  65                 // HotSpot implementation detail: asking for the hash code
  66                 // when the object is locked causes monitor inflation.
  67                 if (obj.hashCode() == 0xBAD) System.out.println("!");
  68                 Asserts.assertEQ(wb.isMonitorInflated(obj), true,
  69                                  "Monitor should be inflated.");
  70             }
  71             boolean did_deflation = wb.deflateIdleMonitors();
  72             Asserts.assertEQ(did_deflation, true,
  73                              "deflateIdleMonitors() should have worked.");
  74             Asserts.assertEQ(wb.isMonitorInflated(obj), false,
  75                              "Monitor should be deflated.");
  76         }
  77     }
  78 }