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 }