1 /*
2 * Copyright (c) 2020, 2023, 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 package gc.shenandoah;
25
26 /* @test id=satb
27 * @requires vm.gc.Shenandoah
28 * @library /test/lib
29 * @build jdk.test.whitebox.WhiteBox
30 * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
31 * @run main/othervm
32 * -Xbootclasspath/a:.
33 * -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
34 * -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCMode=satb
35 * gc.shenandoah.TestReferenceRefersToShenandoah
36 */
37
38 /* @test id=satb-100
39 * @requires vm.gc.Shenandoah
40 * @library /test/lib
41 * @build jdk.test.whitebox.WhiteBox
42 * @modules java.base
43 * @run main jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
44 * @run main/othervm
45 * -Xbootclasspath/a:.
46 * -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
47 * -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCMode=satb -XX:ShenandoahGarbageThreshold=100 -Xmx100m
48 * gc.shenandoah.TestReferenceRefersToShenandoah
49 */
50
51 /* @test id=generational
52 * @requires vm.gc.Shenandoah
53 * @library /test/lib
54 * @build jdk.test.whitebox.WhiteBox
55 * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
56 * @run main/othervm
57 * -Xbootclasspath/a:.
58 * -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
59 * -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCMode=generational
60 * gc.shenandoah.TestReferenceRefersToShenandoah
61 */
62
63 /* @test id=generational-100
64 * @requires vm.gc.Shenandoah
65 * @library /test/lib
66 * @build jdk.test.whitebox.WhiteBox
67 * @modules java.base
68 * @run main jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
69 * @run main/othervm
70 * -Xbootclasspath/a:.
71 * -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
72 * -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCMode=generational -XX:ShenandoahGarbageThreshold=100 -Xmx100m
73 * gc.shenandoah.TestReferenceRefersToShenandoah
74 */
75
76 import java.lang.ref.PhantomReference;
77 import java.lang.ref.Reference;
78 import java.lang.ref.ReferenceQueue;
79 import java.lang.ref.WeakReference;
80 import jdk.test.whitebox.WhiteBox;
81
82 public class TestReferenceRefersToShenandoah {
83 private static final WhiteBox WB = WhiteBox.getWhiteBox();
84
85 private static final class TestObject {
86 public final int value;
87
88 public TestObject(int value) {
89 this.value = value;
90 }
91 }
92
93 private static volatile TestObject testObjectNone = null;
94 private static volatile TestObject testObject1 = null;
95 private static volatile TestObject testObject2 = null;
96 private static volatile TestObject testObject3 = null;
97 private static volatile TestObject testObject4 = null;
98
99 private static ReferenceQueue<TestObject> queue = null;
100
101 private static PhantomReference<TestObject> testPhantom1 = null;
102
103 private static WeakReference<TestObject> testWeak2 = null;
104 private static WeakReference<TestObject> testWeak3 = null;
105 private static WeakReference<TestObject> testWeak4 = null;
106
107 private static void setup() {
108 testObjectNone = new TestObject(0);
109 testObject1 = new TestObject(1);
110 testObject2 = new TestObject(2);
111 testObject3 = new TestObject(3);
112 testObject4 = new TestObject(4);
113
114 queue = new ReferenceQueue<TestObject>();
115
116 testPhantom1 = new PhantomReference<TestObject>(testObject1, queue);
117
118 testWeak2 = new WeakReference<TestObject>(testObject2, queue);
119 testWeak3 = new WeakReference<TestObject>(testObject3, queue);
120 testWeak4 = new WeakReference<TestObject>(testObject4, queue);
121 }
122
123 private static void gcUntilOld(Object o) throws Exception {
124 if (!WB.isObjectInOldGen(o)) {
125 WB.fullGC();
126 if (!WB.isObjectInOldGen(o)) {
127 // This is just a warning, because failing would
128 // be overspecifying for generational shenandoah,
129 // which need not necessarily promote objects upon
130 // a full GC.
131 warn("object not promoted by full gc");
132 }
133 }
134 }
135
136 private static void gcUntilOld() throws Exception {
137 gcUntilOld(testObjectNone);
138 gcUntilOld(testObject1);
139 gcUntilOld(testObject2);
140 gcUntilOld(testObject3);
141 gcUntilOld(testObject4);
142
143 gcUntilOld(testPhantom1);
144
145 gcUntilOld(testWeak2);
146 gcUntilOld(testWeak3);
147 gcUntilOld(testWeak4);
148 }
149
150 private static void progress(String msg) {
151 System.out.println(msg);
152 }
153
154 private static void fail(String msg) throws Exception {
155 throw new RuntimeException(msg);
156 }
157
158 private static void warn(String msg) {
159 System.out.println("Warning: " + msg);
160 }
161
162 private static void expectCleared(Reference<TestObject> ref,
163 String which) throws Exception {
164 expectNotValue(ref, testObjectNone, which);
165 if (!ref.refersTo(null)) {
166 fail("expected " + which + " to be cleared");
167 }
168 }
169
170 private static void expectNotCleared(Reference<TestObject> ref,
171 String which) throws Exception {
172 expectNotValue(ref, testObjectNone, which);
173 if (ref.refersTo(null)) {
174 fail("expected " + which + " to not be cleared");
175 }
176 }
177
178 private static void expectValue(Reference<TestObject> ref,
179 TestObject value,
180 String which) throws Exception {
181 expectNotValue(ref, testObjectNone, which);
182 expectNotCleared(ref, which);
183 if (!ref.refersTo(value)) {
184 fail(which + " doesn't refer to expected value");
185 }
186 }
187
188 private static void expectNotValue(Reference<TestObject> ref,
189 TestObject value,
190 String which) throws Exception {
191 if (ref.refersTo(value)) {
192 fail(which + " refers to unexpected value");
193 }
194 }
195
196 private static void checkInitialStates() throws Exception {
197 expectValue(testPhantom1, testObject1, "testPhantom1");
198 expectValue(testWeak2, testObject2, "testWeak2");
199 expectValue(testWeak3, testObject3, "testWeak3");
200 expectValue(testWeak4, testObject4, "testWeak4");
201 }
202
203 private static void discardStrongReferences() {
204 // testObjectNone not dropped
205 testObject1 = null;
206 testObject2 = null;
207 // testObject3 not dropped
208 testObject4 = null;
209 }
210
211 private static void testConcurrentCollection() throws Exception {
212 progress("setup concurrent collection test");
213 setup();
214 progress("gcUntilOld");
215 gcUntilOld();
216
217 progress("acquire control of concurrent cycles");
218 WB.concurrentGCAcquireControl();
219 try {
220 progress("check initial states");
221 checkInitialStates();
222
223 progress("discard strong references");
224 discardStrongReferences();
225
226 progress("run GC to before marking completed");
227 WB.concurrentGCRunTo(WB.BEFORE_MARKING_COMPLETED);
228
229 progress("fetch test objects, possibly keeping some alive");
230 expectNotCleared(testPhantom1, "testPhantom1");
231 expectNotCleared(testWeak2, "testWeak2");
232 expectValue(testWeak3, testObject3, "testWeak3");
233
234 // For some collectors, calling get() will keep testObject4 alive.
235 if (testWeak4.get() == null) {
236 fail("testWeak4 unexpectedly == null");
237 }
238
239 progress("finish collection");
240 WB.concurrentGCRunToIdle();
241
242 progress("verify expected clears");
243 expectCleared(testPhantom1, "testPhantom1");
244 expectCleared(testWeak2, "testWeak2");
245 expectValue(testWeak3, testObject3, "testWeak3");
246 expectNotCleared(testWeak4, "testWeak4");
247
248 progress("verify get returns expected values");
249 if (testWeak2.get() != null) {
250 fail("testWeak2.get() != null");
251 }
252
253 TestObject obj3 = testWeak3.get();
254 if (obj3 == null) {
255 fail("testWeak3.get() returned null");
256 } else if (obj3.value != 3) {
257 fail("testWeak3.get().value is " + obj3.value);
258 }
259
260 TestObject obj4 = testWeak4.get();
261 if (obj4 == null) {
262 fail("testWeak4.get() returned null");
263 } else if (obj4.value != 4) {
264 fail("testWeak4.get().value is " + obj4.value);
265 }
266
267 progress("verify queue entries");
268 long timeout = 60000; // 1 minute of milliseconds.
269 while (true) {
270 Reference<? extends TestObject> ref = queue.remove(timeout);
271 if (ref == null) {
272 break;
273 } else if (ref == testPhantom1) {
274 testPhantom1 = null;
275 } else if (ref == testWeak2) {
276 testWeak2 = null;
277 } else if (ref == testWeak3) {
278 testWeak3 = null;
279 } else if (ref == testWeak4) {
280 testWeak4 = null;
281 } else {
282 fail("unexpected reference in queue");
283 }
284 }
285 if (testPhantom1 != null) {
286 fail("testPhantom1 not notified");
287 } else if (testWeak2 != null) {
288 fail("testWeak2 not notified");
289 } else if (testWeak3 == null) {
290 fail("testWeak3 notified");
291 } else if (testWeak4 == null) {
292 if (obj4 != null) {
293 fail("testWeak4 notified");
294 }
295 }
296
297 } finally {
298 progress("release control of concurrent cycles");
299 WB.concurrentGCReleaseControl();
300 }
301 progress("finished concurrent collection test");
302 }
303
304 private static void testSimpleCollection() throws Exception {
305 progress("setup simple collection test");
306 setup();
307 progress("gcUntilOld");
308 gcUntilOld();
309
310 progress("check initial states");
311 checkInitialStates();
312
313 progress("discard strong references");
314 TestObject tw4 = testWeak4.get(); // Keep testObject4 alive.
315 discardStrongReferences();
316
317 progress("collect garbage");
318 WB.fullGC();
319
320 progress("verify expected clears");
321 expectCleared(testPhantom1, "testPhantom1");
322 expectCleared(testWeak2, "testWeak2");
323 expectValue(testWeak3, testObject3, "testWeak3");
324 expectNotCleared(testWeak4, "testWeak4");
325
326 progress("verify get returns expected values");
327 if (testWeak2.get() != null) {
328 fail("testWeak2.get() != null");
329 } else if (testWeak3.get() != testObject3) {
330 fail("testWeak3.get() is not expected value");
331 } else if (testWeak4.get() != tw4) {
332 fail("testWeak4.get() is not expected value");
333 }
334
335 progress("finished simple collection test");
336 }
337
338 public static void main(String[] args) throws Exception {
339 if (WB.supportsConcurrentGCBreakpoints()) {
340 testConcurrentCollection();
341 }
342 testSimpleCollection();
343 }
344 }