1 /* 2 * Copyright (c) 2018, Red Hat, Inc. 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 /* 26 * @test TestRefprocSanity 27 * @summary Test that null references/referents work fine 28 * @key gc 29 * @requires vm.gc.Shenandoah & !vm.graal.enabled 30 * 31 * @run main/othervm -Xmx1g -Xms1g -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions 32 * -XX:+UseShenandoahGC 33 * -XX:+ShenandoahVerify 34 * TestRefprocSanity 35 * 36 * @run main/othervm -Xmx1g -Xms1g -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions 37 * -XX:+UseShenandoahGC 38 * TestRefprocSanity 39 * 40 * @run main/othervm -Xmx1g -Xms1g -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions 41 * -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=aggressive 42 * TestRefprocSanity 43 */ 44 45 import java.lang.ref.*; 46 47 public class TestRefprocSanity { 48 49 static final long TARGET_MB = Long.getLong("target", 10_000); // 10 Gb allocation 50 static final int WINDOW = 10_000; 51 52 static final Reference<MyObject>[] refs = new Reference[WINDOW]; 53 54 public static void main(String[] args) throws Exception { 55 long count = TARGET_MB * 1024 * 1024 / 32; 56 int rIdx = 0; 57 58 ReferenceQueue rq = new ReferenceQueue(); 59 60 for (int c = 0; c < WINDOW; c++) { 61 refs[c] = select(c, new MyObject(c), rq); 62 } 63 64 for (int c = 0; c < count; c++) { 65 verifyRefAt(rIdx); 66 refs[rIdx] = select(c, new MyObject(rIdx), rq); 67 68 rIdx++; 69 if (rIdx >= WINDOW) { 70 rIdx = 0; 71 } 72 while (rq.poll() != null); // drain 73 } 74 } 75 76 static Reference<MyObject> select(int v, MyObject ext, ReferenceQueue rq) { 77 switch (v % 10) { 78 case 0: return new SoftReference<MyObject>(null); 79 case 1: return new SoftReference<MyObject>(null, rq); 80 case 2: return new SoftReference<MyObject>(ext); 81 case 3: return new SoftReference<MyObject>(ext, rq); 82 case 4: return new WeakReference<MyObject>(null); 83 case 5: return new WeakReference<MyObject>(null, rq); 84 case 6: return new WeakReference<MyObject>(ext); 85 case 7: return new WeakReference<MyObject>(ext, rq); 86 case 8: return new PhantomReference<MyObject>(null, rq); 87 case 9: return new PhantomReference<MyObject>(ext, rq); 88 default: throw new IllegalStateException(); 89 } 90 } 91 92 static void verifyRefAt(int idx) { 93 Reference<MyObject> ref = refs[idx]; 94 MyObject mo = ref.get(); 95 if (mo != null && mo.x != idx) { 96 throw new IllegalStateException("Referent tag is incorrect: " + mo.x + ", should be " + idx); 97 } 98 } 99 100 static class MyObject { 101 final int x; 102 103 public MyObject(int x) { 104 this.x = x; 105 } 106 } 107 108 }