1 /*
   2  * Copyright (c) 2015, 2018, 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.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 package jdk.jfr.event.oldobject;
  26 
  27 import java.util.List;
  28 
  29 import jdk.jfr.Recording;
  30 import jdk.jfr.consumer.RecordedEvent;
  31 import jdk.jfr.internal.test.WhiteBox;
  32 import jdk.test.lib.jfr.EventNames;
  33 import jdk.test.lib.jfr.Events;
  34 
  35 /*
  36  * @test
  37  * @key jfr
  38  * @requires vm.gc == "null"
  39  * @library /test/lib /test/jdk
  40  * @modules jdk.jfr/jdk.jfr.internal.test
  41  * @run main/othervm -XX:TLABSize=2k jdk.jfr.event.oldobject.TestReferenceChainLimit
  42  */
  43 public class TestReferenceChainLimit {
  44     private final static int TEST_CHAIN_LENGTH_FACTOR = 10; // scaling factor for the how long chain to be used in the test
  45 
  46     final static class ChainNode {
  47         final ChainNode next;
  48         byte[] leak;
  49 
  50         public ChainNode(ChainNode node) {
  51             next = node;
  52             leak = new byte[10_000];
  53         }
  54     }
  55 
  56     private static ChainNode createChain() {
  57         ChainNode node = null;
  58         final int testChainLength = OldObjects.MAX_CHAIN_LENGTH * TEST_CHAIN_LENGTH_FACTOR;
  59         for (int i = 0; i < testChainLength; i++) {
  60             node = new ChainNode(node);
  61         }
  62         return node;
  63     }
  64 
  65     public static ChainNode leak;
  66 
  67     public static void main(String[] args) throws Exception {
  68         WhiteBox.setWriteAllObjectSamples(true);
  69 
  70         try (Recording r = new Recording()) {
  71             r.enable(EventNames.OldObjectSample).withStackTrace().with("cutoff", "infinity");
  72             r.start();
  73             leak = createChain();
  74             List<RecordedEvent> events = Events.fromRecording(r);
  75             if (OldObjects.countMatchingEvents(events, byte[].class, null, null, -1, "createChain") == 0) {
  76                 throw new Exception("Could not find ChainNode");
  77             }
  78             for (RecordedEvent e : events) {
  79                 OldObjects.validateReferenceChainLimit(e, OldObjects.MAX_CHAIN_LENGTH);
  80             }
  81         }
  82     }
  83 }