1 /* 2 * Copyright (c) 2014, 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 /* 25 * @test TestDeferredRSUpdate 26 * @bug 8040977 8052170 27 * @summary Ensure that running with -XX:-G1DeferredRSUpdate does not crash the VM 28 * @key gc 29 * @library /testlibrary 30 */ 31 32 import com.oracle.java.testlibrary.ProcessTools; 33 import com.oracle.java.testlibrary.OutputAnalyzer; 34 35 public class TestDeferredRSUpdate { 36 public static void main(String[] args) throws Exception { 37 GCTest.main(args); 38 39 ProcessBuilder pb = ProcessTools.createJavaProcessBuilder("-XX:+UseG1GC", 40 "-Xmx10M", 41 "-XX:+PrintGCDetails", 42 // G1DeferredRSUpdate is a develop option, but we cannot limit execution of this test to only debug VMs. 43 "-XX:+IgnoreUnrecognizedVMOptions", 44 "-XX:-G1DeferredRSUpdate", 45 GCTest.class.getName()); 46 47 OutputAnalyzer output = new OutputAnalyzer(pb.start()); 48 output.shouldHaveExitValue(0); 49 } 50 51 static class GCTest { 52 private static Object[] garbage = new Object[32]; 53 54 public static void main(String [] args) { 55 System.out.println("Creating garbage"); 56 // Create 128MB of garbage. This should result in at least one minor GC, with 57 // some objects copied to old gen. As references from old to young are installed, 58 // the crash due to the use before initialize occurs. 59 Object prev = null; 60 Object prevPrev = null; 61 for (int i = 0; i < 1024; i++) { 62 Object[] next = new Object[32 * 1024]; 63 next[0] = prev; 64 next[1] = prevPrev; 65 66 Object[] cur = (Object[]) garbage[i % garbage.length]; 67 if (cur != null) { 68 cur[0] = null; 69 cur[1] = null; 70 } 71 garbage[i % garbage.length] = next; 72 73 prevPrev = prev; 74 prev = next; 75 } 76 System.out.println("Done"); 77 } 78 } 79 }