1 /*
 2  * Copyright Amazon.com Inc. 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  * @test
26  * @summary Tests that recursive locking doesn't cause excessive native memory usage
27  * @library /test/lib
28  * @build jdk.test.whitebox.WhiteBox
29  * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
30  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
31  *                   -Xmx100M -XX:AsyncDeflationInterval=0 -XX:GuaranteedAsyncDeflationInterval=0
32  *                   -Xlog:monitorinflation=trace
33  *                   TestRecursiveMonitorChurn
34  */
35 
36 import jdk.test.whitebox.WhiteBox;
37 import jtreg.SkippedException;
38 
39 public class TestRecursiveMonitorChurn {
40     static class Monitor {
41         public static volatile int i, j;
42         synchronized void doSomething() {
43             i++;
44             doSomethingElse();
45         }
46         synchronized void doSomethingElse() {
47             j++;
48         }
49     }
50 
51     static final WhiteBox WB = WhiteBox.getWhiteBox();
52     static final int LM_MONITOR = 0;
53     static final int COUNT = 100000;
54 
55     public static volatile Monitor monitor;
56     public static void main(String[] args) {
57         if (WB.getIntVMFlag("LockingMode") == LM_MONITOR) {
58             throw new SkippedException("LM_MONITOR always inflates. Invalid test.");
59         }
60         final long pre_monitor_count = WB.getInUseMonitorCount();
61         System.out.println(" Precount = " + pre_monitor_count);
62         for (int i = 0; i < COUNT; i++) {
63             monitor = new Monitor();
64             monitor.doSomething();
65         }
66         System.out.println("i + j = " + (Monitor.i + Monitor.j));
67         final long post_monitor_count = WB.getInUseMonitorCount();
68         System.out.println("Postcount = " + post_monitor_count);
69 
70         if (pre_monitor_count != post_monitor_count) {
71             final long monitor_count_change = post_monitor_count - pre_monitor_count;
72             System.out.println("Unexpected change in monitor count: " + monitor_count_change);
73             if (monitor_count_change < 0) {
74                 throw new RuntimeException("Unexpected Deflation");
75             }
76             throw new RuntimeException("Unexpected Inflation");
77         }
78     }
79 }