1 /* 2 * Copyright (c) 2018, Red Hat, Inc. All rights reserved. 3 * 4 * This code is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 only, as 6 * published by the Free Software Foundation. 7 * 8 * This code is distributed in the hope that it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 11 * version 2 for more details (a copy is included in the LICENSE file that 12 * accompanied this code). 13 * 14 * You should have received a copy of the GNU General Public License version 15 * 2 along with this work; if not, write to the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 17 * 18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 19 * or visit www.oracle.com if you need additional information or have any 20 * questions. 21 * 22 */ 23 24 /* 25 * @test TestRefprocSanity 26 * @summary Test that null references/referents work fine 27 * @key gc 28 * @requires vm.gc.Shenandoah 29 * 30 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g TestRefprocSanity 31 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:+ShenandoahVerify TestRefprocSanity 32 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahGCHeuristics=aggressive TestRefprocSanity 33 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:+ShenandoahVerify -XX:ShenandoahGCHeuristics=traversal TestRefprocSanity 34 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahGCHeuristics=traversal TestRefprocSanity 35 */ 36 37 import java.lang.ref.*; 38 39 public class TestRefprocSanity { 40 41 static final long TARGET_MB = Long.getLong("target", 10_000); // 10 Gb allocation 42 static final int WINDOW = 10_000; 43 44 static final Reference<MyObject>[] refs = new Reference[WINDOW]; 45 46 public static void main(String[] args) throws Exception { 47 long count = TARGET_MB * 1024 * 1024 / 32; 48 int rIdx = 0; 49 50 ReferenceQueue rq = new ReferenceQueue(); 51 52 for (int c = 0; c < WINDOW; c++) { 53 refs[c] = select(c, new MyObject(c), rq); 54 } 55 56 for (int c = 0; c < count; c++) { 57 verifyRefAt(rIdx); 58 refs[rIdx] = select(c, new MyObject(rIdx), rq); 59 60 rIdx++; 61 if (rIdx >= WINDOW) { 62 rIdx = 0; 63 } 64 while (rq.poll() != null); // drain 65 } 66 } 67 68 static Reference<MyObject> select(int v, MyObject ext, ReferenceQueue rq) { 69 switch (v % 10) { 70 case 0: return new SoftReference<MyObject>(null); 71 case 1: return new SoftReference<MyObject>(null, rq); 72 case 2: return new SoftReference<MyObject>(ext); 73 case 3: return new SoftReference<MyObject>(ext, rq); 74 case 4: return new WeakReference<MyObject>(null); 75 case 5: return new WeakReference<MyObject>(null, rq); 76 case 6: return new WeakReference<MyObject>(ext); 77 case 7: return new WeakReference<MyObject>(ext, rq); 78 case 8: return new PhantomReference<MyObject>(null, rq); 79 case 9: return new PhantomReference<MyObject>(ext, rq); 80 default: throw new IllegalStateException(); 81 } 82 } 83 84 static void verifyRefAt(int idx) { 85 Reference<MyObject> ref = refs[idx]; 86 MyObject mo = ref.get(); 87 if (mo != null && mo.x != idx) { 88 throw new IllegalStateException("Referent tag is incorrect: " + mo.x + ", should be " + idx); 89 } 90 } 91 92 static class MyObject { 93 final int x; 94 95 public MyObject(int x) { 96 this.x = x; 97 } 98 } 99 100 }