rev 12487 : 8172049: [s390] Implement "JEP 270: Reserved Stack Areas for Critical Sections".
Reviewed-by: mdoerr
1 /*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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7 * published by the Free Software Foundation.
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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 * @test ReservedStackTest
26 * @library /test/lib
27 * @modules java.base/jdk.internal.misc
28 * @modules java.base/jdk.internal.vm.annotation
29 * @run main/othervm -Xint ReservedStackTest
30 * @run main/othervm -XX:-Inline -XX:CompileCommand=exclude,java/util/concurrent/locks/AbstractOwnableSynchronizer.setExclusiveOwnerThread ReservedStackTest
31 */
32
33 /* The exclusion of java.util.concurrent.locks.AbstractOwnableSynchronizer.setExclusiveOwnerThread()
34 * from the compilable methods is required to ensure that the test will be able
35 * to trigger a StackOverflowError on the right method.
36 */
37
38
39 /*
40 * Notes about this test:
41 * This test tries to reproduce a rare but nasty corruption bug that
42 * occurs when a StackOverflowError is thrown in some critical sections
43 * of the ReentrantLock implementation.
44 *
45 * Here's the critical section where a corruption could occur
46 * (from java.util.concurrent.ReentrantLock.java)
47 *
48 * final void lock() {
49 * if (compareAndSetState(0, 1))
50 * setExclusiveOwnerThread(Thread.currentThread());
51 * else
52 * acquire(1);
53 * }
54 *
55 * The corruption occurs when the compareAndSetState(0, 1)
56 * successfully updates the status of the lock but the method
57 * fails to set the owner because of a stack overflow.
58 * HotSpot checks for stack overflow on method invocations.
59 * The test must trigger a stack overflow either when
60 * Thread.currentThread() or setExclusiveOwnerThread() is
61 * invoked.
62 *
63 * The test starts with a recursive invocation loop until a
64 * first StackOverflowError is thrown, the Error is caught
65 * and a few dozen frames are exited. Now the thread has
66 * little free space on its execution stack and will try
67 * to trigger a stack overflow in the critical section.
68 * The test has a huge array of ReentrantLocks instances.
69 * The thread invokes a recursive method which, at each
70 * of its invocations, tries to acquire the next lock
71 * in the array. The execution continues until a
72 * StackOverflowError is thrown or the end of the array
73 * is reached.
74 * If no StackOverflowError has been thrown, the test
75 * is non conclusive (recommendation: increase the size
76 * of the ReentrantLock array).
77 * The status of all Reentrant locks in the array is checked,
78 * if a corruption is detected, the test failed, otherwise
79 * the test passed.
80 *
81 * To have a chance that the stack overflow occurs on one
82 * of the two targeted method invocations, the test is
83 * repeated in different threads. Each Java thread has a
84 * random size area allocated at the beginning of its
85 * stack to prevent false sharing. The test relies on this
86 * to have different stack alignments when it hits the targeted
87 * methods (the test could have been written with a native
88 * method with alloca, but using different Java threads makes
89 * the test 100% Java).
90 *
91 * One additional trick is required to ensure that the stack
92 * overflow will occur on the Thread.currentThread() getter
93 * or the setExclusiveOwnerThread() setter.
94 *
95 * Potential stack overflows are detected by stack banging,
96 * at method invocation time.
97 * In interpreted code, the stack banging performed for the
98 * lock() method goes further than the stack banging performed
99 * for the getter or the setter method, so the potential stack
100 * overflow is detected before entering the critical section.
101 * In compiled code, the getter and the setter are in-lined,
102 * so the stack banging is only performed before entering the
103 * critical section.
104 * In order to have a stack banging that goes further for the
105 * getter/setter methods than for the lock() method, the test
106 * exploits the property that interpreter frames are (much)
107 * bigger than compiled code frames. When the test is run,
108 * a compiler option disables the compilation of the
109 * setExclusiveOwnerThread() method.
110 *
111 */
112
113 import java.util.concurrent.locks.ReentrantLock;
114 import jdk.test.lib.Platform;
115
116 public class ReservedStackTest {
117
118 static class ReentrantLockTest {
119
120 private ReentrantLock lockArray[];
121 // Frame sizes vary a lot between interpreted code and compiled code
122 // so the lock array has to be big enough to cover all cases.
123 // If test fails with message "Not conclusive test", try to increase
124 // LOCK_ARRAY_SIZE value
125 private static final int LOCK_ARRAY_SIZE = 8192;
126 private boolean stackOverflowErrorReceived;
127 StackOverflowError soe = null;
128 private int index = -1;
129
130 public void initialize() {
131 lockArray = new ReentrantLock[LOCK_ARRAY_SIZE];
132 for (int i = 0; i < LOCK_ARRAY_SIZE; i++) {
133 lockArray[i] = new ReentrantLock();
134 }
135 stackOverflowErrorReceived = false;
136 }
137
138 public String getResult() {
139 if (!stackOverflowErrorReceived) {
140 return "ERROR: Not conclusive test: no StackOverflowError received";
141 }
142 for (int i = 0; i < LOCK_ARRAY_SIZE; i++) {
143 if (lockArray[i].isLocked()) {
144 if (!lockArray[i].isHeldByCurrentThread()) {
145 StringBuilder s = new StringBuilder();
146 s.append("FAILED: ReentrantLock ");
147 s.append(i);
148 s.append(" looks corrupted");
149 return s.toString();
150 }
151 }
152 }
153 return "PASSED";
154 }
155
156 public void run() {
157 try {
158 lockAndCall(0);
159 } catch (StackOverflowError e) {
160 soe = e;
161 stackOverflowErrorReceived = true;
162 }
163 }
164
165 private void lockAndCall(int i) {
166 index = i;
167 if (i < LOCK_ARRAY_SIZE) {
168 lockArray[i].lock();
169 lockAndCall(i + 1);
170 }
171 }
172 }
173
174 static class RunWithSOEContext implements Runnable {
175
176 int counter;
177 int deframe;
178 int decounter;
179 int setupSOEFrame;
180 int testStartFrame;
181 ReentrantLockTest test;
182
183 public RunWithSOEContext(ReentrantLockTest test, int deframe) {
184 this.test = test;
185 this.deframe = deframe;
186 }
187
188 @Override
189 @jdk.internal.vm.annotation.ReservedStackAccess
190 public void run() {
191 counter = 0;
192 decounter = deframe;
193 test.initialize();
194 recursiveCall();
195 System.out.println("Framework got StackOverflowError at frame = " + counter);
196 System.out.println("Test started execution at frame = " + (counter - deframe));
197 String result = test.getResult();
198 // The feature is not fully implemented on all platforms,
199 // corruptions are still possible.
200 boolean supportedPlatform =
201 Platform.isAix() ||
202 (Platform.isLinux() && (Platform.isPPC() || Platform.isX64() || Platform.isX86())) ||
203 Platform.isOSX() ||
204 Platform.isSolaris();
205 if (supportedPlatform && !result.contains("PASSED")) {
206 System.out.println(result);
207 throw new Error(result);
208 } else {
209 // Either the test passed or this platform is not supported.
210 // On not supported platforms, we only expect the VM to
211 // not crash during the test. This is especially important
212 // on Windows where the detection of SOE in annotated
213 // sections is implemented but the reserved zone mechanism
214 // to avoid the corruption cannot be implemented yet
215 // because of JDK-8067946
216 System.out.println("PASSED");
217 }
218 }
219
220 void recursiveCall() {
221 // Unused local variables to increase the frame size
222 long l1, l2, l3, l4, l5, l6, l7, l8, l9, l10, l11, l12, l13, l14, l15, l16, l17, l18, l19;
223 long l20, l21, l22, l23, l24, l25, l26, l27, l28, l30, l31, l32, l33, l34, l35, l36, l37;
224 counter++;
225 try {
226 recursiveCall();
227 } catch (StackOverflowError e) {
228 }
229 decounter--;
230 if (decounter == 0) {
231 setupSOEFrame = counter;
232 testStartFrame = counter - deframe;
233 test.run();
234 }
235 }
236 }
237
238 public static void main(String[] args) {
239 for (int i = 0; i < 1000; i++) {
240 // Each iteration has to be executed by a new thread. The test
241 // relies on the random size area pushed by the VM at the beginning
242 // of the stack of each Java thread it creates.
243 Thread thread = new Thread(new RunWithSOEContext(new ReentrantLockTest(), 256));
244 thread.start();
245 try {
246 thread.join();
247 } catch (InterruptedException ex) { }
248 }
249 }
250 }
--- EOF ---