1 /*
2 * Copyright (c) 2020, 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 compiler.valhalla.valuetypes;
25
26 import java.lang.invoke.*;
27 import java.lang.reflect.Field;
28 import java.lang.reflect.Method;
29
30 import jdk.test.lib.Asserts;
31 import jdk.internal.misc.Unsafe;
32
33 /**
34 * @test TestBufferTearing
35 * @summary Detect tearing on value type buffer writes due to missing barriers.
36 * @library /testlibrary /test/lib /compiler/whitebox /
37 * @modules java.base/jdk.internal.misc
38 * @run main/othervm -XX:ValueFieldMaxFlatSize=0 -XX:ValueArrayElemMaxFlatSize=0
39 * -XX:+StressGCM -XX:+StressLCM
40 * compiler.valhalla.valuetypes.TestBufferTearing
41 * @run main/othervm -XX:ValueFieldMaxFlatSize=0 -XX:ValueArrayElemMaxFlatSize=0
42 * -XX:+StressGCM -XX:+StressLCM -XX:+AlwaysIncrementalInline
43 * compiler.valhalla.valuetypes.TestBufferTearing
44 * @run main/othervm -XX:ValueFieldMaxFlatSize=0 -XX:ValueArrayElemMaxFlatSize=0
45 * -XX:CompileCommand=dontinline,*::incrementAndCheck*
46 * -XX:+StressGCM -XX:+StressLCM
47 * compiler.valhalla.valuetypes.TestBufferTearing
48 * @run main/othervm -XX:ValueFieldMaxFlatSize=0 -XX:ValueArrayElemMaxFlatSize=0
49 * -XX:CompileCommand=dontinline,*::incrementAndCheck*
50 * -XX:+StressGCM -XX:+StressLCM -XX:+AlwaysIncrementalInline
51 * compiler.valhalla.valuetypes.TestBufferTearing
52 */
53
54 inline class MyValue {
55 int x;
56 int y;
57
58 private static final Unsafe U = Unsafe.getUnsafe();
59 private static final long X_OFFSET;
60 private static final long Y_OFFSET;
61 static {
62 try {
63 Field xField = MyValue.class.getDeclaredField("x");
64 X_OFFSET = U.objectFieldOffset(xField);
65 Field yField = MyValue.class.getDeclaredField("y");
66 Y_OFFSET = U.objectFieldOffset(yField);
67 } catch (Exception e) {
68 throw new RuntimeException(e);
69 }
70 }
71
72 MyValue(int x, int y) {
73 this.x = x;
74 this.y = y;
75 }
76
77 MyValue incrementAndCheck() {
78 Asserts.assertEQ(x, y, "Inconsistent field values");
79 return new MyValue(x + 1, y + 1);
80 }
81
82 MyValue incrementAndCheckUnsafe() {
83 Asserts.assertEQ(x, y, "Inconsistent field values");
84 MyValue vt = U.makePrivateBuffer(this);
85 U.putInt(vt, X_OFFSET, x + 1);
86 U.putInt(vt, Y_OFFSET, y + 1);
87 return U.finishPrivateBuffer(vt);
88 }
89 }
90
91 public class TestBufferTearing {
92
93 static MyValue vtField1;
94 MyValue vtField2;
95 MyValue[] vtField3 = new MyValue[1];
96
97 static final MethodHandle incrementAndCheck_mh;
98
99 static {
100 try {
101 Class<?> clazz = MyValue.class;
102 MethodHandles.Lookup lookup = MethodHandles.lookup();
103
104 MethodType mt = MethodType.methodType(MyValue.class);
105 incrementAndCheck_mh = lookup.findVirtual(clazz, "incrementAndCheck", mt);
106 } catch (NoSuchMethodException | IllegalAccessException e) {
107 e.printStackTrace();
108 throw new RuntimeException("Method handle lookup failed");
109 }
110 }
111
112 static class Runner extends Thread {
113 TestBufferTearing test;
114
115 public Runner(TestBufferTearing test) {
116 this.test = test;
117 }
118
119 public void run() {
120 for (int i = 0; i < 1_000_000; ++i) {
121 test.vtField1 = test.vtField1.incrementAndCheck();
122 test.vtField2 = test.vtField2.incrementAndCheck();
123 test.vtField3[0] = test.vtField3[0].incrementAndCheck();
124
125 test.vtField1 = test.vtField1.incrementAndCheckUnsafe();
126 test.vtField2 = test.vtField2.incrementAndCheckUnsafe();
127 test.vtField3[0] = test.vtField3[0].incrementAndCheckUnsafe();
128
129 try {
130 test.vtField1 = (MyValue)incrementAndCheck_mh.invokeExact(test.vtField1);
131 test.vtField2 = (MyValue)incrementAndCheck_mh.invokeExact(test.vtField2);
132 test.vtField3[0] = (MyValue)incrementAndCheck_mh.invokeExact(test.vtField3[0]);
133 } catch (Throwable t) {
134 throw new RuntimeException("Invoke failed", t);
135 }
136 }
137 }
138 }
139
140 public static void main(String[] args) throws Exception {
141 // Create threads that concurrently update some value type (array) fields
142 // and check the fields of the value types for consistency to detect tearing.
143 TestBufferTearing test = new TestBufferTearing();
144 Thread runner = null;
145 for (int i = 0; i < 10; ++i) {
146 runner = new Runner(test);
147 runner.start();
148 }
149 runner.join();
150 }
151 }