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 /* @test id=iu
77 * @requires vm.gc.Shenandoah
78 * @library /test/lib
79 * @build jdk.test.whitebox.WhiteBox
80 * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
81 * @run main/othervm
82 * -Xbootclasspath/a:.
83 * -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
84 * -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCMode=iu
85 * gc.shenandoah.TestReferenceRefersToShenandoah
86 */
87
88 /* @test id=iu-100
89 * @requires vm.gc.Shenandoah
90 * @library /test/lib
91 * @build jdk.test.whitebox.WhiteBox
92 * @modules java.base
93 * @run main jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
94 * @run main/othervm
95 * -Xbootclasspath/a:.
96 * -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
97 * -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCMode=iu -XX:ShenandoahGarbageThreshold=100 -Xmx100m
98 * gc.shenandoah.TestReferenceRefersToShenandoah
99 */
100
101 import java.lang.ref.PhantomReference;
102 import java.lang.ref.Reference;
103 import java.lang.ref.ReferenceQueue;
104 import java.lang.ref.WeakReference;
105 import jdk.test.whitebox.WhiteBox;
106
107 public class TestReferenceRefersToShenandoah {
108 private static final WhiteBox WB = WhiteBox.getWhiteBox();
109
110 private static final class TestObject {
111 public final int value;
112
113 public TestObject(int value) {
114 this.value = value;
115 }
116 }
117
118 private static volatile TestObject testObjectNone = null;
119 private static volatile TestObject testObject1 = null;
120 private static volatile TestObject testObject2 = null;
121 private static volatile TestObject testObject3 = null;
122 private static volatile TestObject testObject4 = null;
123
124 private static ReferenceQueue<TestObject> queue = null;
125
126 private static PhantomReference<TestObject> testPhantom1 = null;
127
128 private static WeakReference<TestObject> testWeak2 = null;
129 private static WeakReference<TestObject> testWeak3 = null;
130 private static WeakReference<TestObject> testWeak4 = null;
131
132 private static void setup() {
133 testObjectNone = new TestObject(0);
134 testObject1 = new TestObject(1);
135 testObject2 = new TestObject(2);
136 testObject3 = new TestObject(3);
137 testObject4 = new TestObject(4);
138
139 queue = new ReferenceQueue<TestObject>();
140
141 testPhantom1 = new PhantomReference<TestObject>(testObject1, queue);
142
143 testWeak2 = new WeakReference<TestObject>(testObject2, queue);
144 testWeak3 = new WeakReference<TestObject>(testObject3, queue);
145 testWeak4 = new WeakReference<TestObject>(testObject4, queue);
146 }
147
148 private static void gcUntilOld(Object o) throws Exception {
149 if (!WB.isObjectInOldGen(o)) {
150 WB.fullGC();
151 if (!WB.isObjectInOldGen(o)) {
152 fail("object not promoted by full gc");
153 }
154 }
155 }
156
157 private static void gcUntilOld() throws Exception {
158 gcUntilOld(testObjectNone);
159 gcUntilOld(testObject1);
160 gcUntilOld(testObject2);
161 gcUntilOld(testObject3);
162 gcUntilOld(testObject4);
163
164 gcUntilOld(testPhantom1);
165
166 gcUntilOld(testWeak2);
167 gcUntilOld(testWeak3);
168 gcUntilOld(testWeak4);
169 }
170
171 private static void progress(String msg) {
172 System.out.println(msg);
173 }
174
175 private static void fail(String msg) throws Exception {
176 throw new RuntimeException(msg);
177 }
178
179 private static void expectCleared(Reference<TestObject> ref,
180 String which) throws Exception {
181 expectNotValue(ref, testObjectNone, which);
182 if (!ref.refersTo(null)) {
183 fail("expected " + which + " to be cleared");
184 }
185 }
186
187 private static void expectNotCleared(Reference<TestObject> ref,
188 String which) throws Exception {
189 expectNotValue(ref, testObjectNone, which);
190 if (ref.refersTo(null)) {
191 fail("expected " + which + " to not be cleared");
192 }
193 }
194
195 private static void expectValue(Reference<TestObject> ref,
196 TestObject value,
197 String which) throws Exception {
198 expectNotValue(ref, testObjectNone, which);
199 expectNotCleared(ref, which);
200 if (!ref.refersTo(value)) {
201 fail(which + " doesn't refer to expected value");
202 }
203 }
204
205 private static void expectNotValue(Reference<TestObject> ref,
206 TestObject value,
207 String which) throws Exception {
208 if (ref.refersTo(value)) {
209 fail(which + " refers to unexpected value");
210 }
211 }
212
213 private static void checkInitialStates() throws Exception {
214 expectValue(testPhantom1, testObject1, "testPhantom1");
215 expectValue(testWeak2, testObject2, "testWeak2");
216 expectValue(testWeak3, testObject3, "testWeak3");
217 expectValue(testWeak4, testObject4, "testWeak4");
218 }
219
220 private static void discardStrongReferences() {
221 // testObjectNone not dropped
222 testObject1 = null;
223 testObject2 = null;
224 // testObject3 not dropped
225 testObject4 = null;
226 }
227
228 private static boolean isShenandoahIUMode() {
229 return "iu".equals(WB.getStringVMFlag("ShenandoahGCMode"));
230 }
231
232 private static void testConcurrentCollection() throws Exception {
233 progress("setup concurrent collection test");
234 setup();
235 progress("gcUntilOld");
236 gcUntilOld();
237
238 progress("acquire control of concurrent cycles");
239 WB.concurrentGCAcquireControl();
240 try {
241 progress("check initial states");
242 checkInitialStates();
243
244 progress("discard strong references");
245 discardStrongReferences();
246
247 progress("run GC to before marking completed");
248 WB.concurrentGCRunTo(WB.BEFORE_MARKING_COMPLETED);
249
250 progress("fetch test objects, possibly keeping some alive");
251 expectNotCleared(testPhantom1, "testPhantom1");
252 expectNotCleared(testWeak2, "testWeak2");
253 expectValue(testWeak3, testObject3, "testWeak3");
254
255 // For some collectors, calling get() will keep testObject4 alive.
256 if (testWeak4.get() == null) {
257 fail("testWeak4 unexpectedly == null");
258 }
259
260 progress("finish collection");
261 WB.concurrentGCRunToIdle();
262
263 progress("verify expected clears");
264 expectCleared(testPhantom1, "testPhantom1");
265 expectCleared(testWeak2, "testWeak2");
266 expectValue(testWeak3, testObject3, "testWeak3");
267 // This is true for all currently supported concurrent collectors,
268 // except Shenandoah+IU, which allows clearing refs even when
269 // accessed during concurrent marking.
270 if (isShenandoahIUMode()) {
271 expectCleared(testWeak4, "testWeak4");
272 } else {
273 expectNotCleared(testWeak4, "testWeak4");
274 }
275
276 progress("verify get returns expected values");
277 if (testWeak2.get() != null) {
278 fail("testWeak2.get() != null");
279 }
280
281 TestObject obj3 = testWeak3.get();
282 if (obj3 == null) {
283 fail("testWeak3.get() returned null");
284 } else if (obj3.value != 3) {
285 fail("testWeak3.get().value is " + obj3.value);
286 }
287
288 TestObject obj4 = testWeak4.get();
289 if (!isShenandoahIUMode()) {
290 if (obj4 == null) {
291 fail("testWeak4.get() returned null");
292 } else if (obj4.value != 4) {
293 fail("testWeak4.get().value is " + obj4.value);
294 }
295 }
296
297 progress("verify queue entries");
298 long timeout = 60000; // 1 minute of milliseconds.
299 while (true) {
300 Reference<? extends TestObject> ref = queue.remove(timeout);
301 if (ref == null) {
302 break;
303 } else if (ref == testPhantom1) {
304 testPhantom1 = null;
305 } else if (ref == testWeak2) {
306 testWeak2 = null;
307 } else if (ref == testWeak3) {
308 testWeak3 = null;
309 } else if (ref == testWeak4) {
310 testWeak4 = null;
311 } else {
312 fail("unexpected reference in queue");
313 }
314 }
315 if (testPhantom1 != null) {
316 fail("testPhantom1 not notified");
317 } else if (testWeak2 != null) {
318 fail("testWeak2 not notified");
319 } else if (testWeak3 == null) {
320 fail("testWeak3 notified");
321 } else if (testWeak4 == null) {
322 if (obj4 != null) {
323 fail("testWeak4 notified");
324 }
325 }
326
327 } finally {
328 progress("release control of concurrent cycles");
329 WB.concurrentGCReleaseControl();
330 }
331 progress("finished concurrent collection test");
332 }
333
334 private static void testSimpleCollection() throws Exception {
335 progress("setup simple collection test");
336 setup();
337 progress("gcUntilOld");
338 gcUntilOld();
339
340 progress("check initial states");
341 checkInitialStates();
342
343 progress("discard strong references");
344 TestObject tw4 = testWeak4.get(); // Keep testObject4 alive.
345 discardStrongReferences();
346
347 progress("collect garbage");
348 WB.fullGC();
349
350 progress("verify expected clears");
351 expectCleared(testPhantom1, "testPhantom1");
352 expectCleared(testWeak2, "testWeak2");
353 expectValue(testWeak3, testObject3, "testWeak3");
354 expectNotCleared(testWeak4, "testWeak4");
355
356 progress("verify get returns expected values");
357 if (testWeak2.get() != null) {
358 fail("testWeak2.get() != null");
359 } else if (testWeak3.get() != testObject3) {
360 fail("testWeak3.get() is not expected value");
361 } else if (testWeak4.get() != tw4) {
362 fail("testWeak4.get() is not expected value");
363 }
364
365 progress("finished simple collection test");
366 }
367
368 public static void main(String[] args) throws Exception {
369 if (WB.supportsConcurrentGCBreakpoints()) {
370 testConcurrentCollection();
371 }
372 testSimpleCollection();
373 }
374 }