1 /*
2 * Copyright (c) 2016, 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 /*
25 * @test
26 * @bug 8140520
27 * @summary Setting small CompilerThreadStackSize, ThreadStackSize, and
28 * VMThreadStackSize values should result in an error message that shows
29 * the minimum stack size value for each thread type.
30 * @compile TooSmallStackSize.java
31 * @run main TooSmallStackSize
32 */
33
34 /*
35 * The primary purpose of this test is to make sure we can run with a
36 * stack smaller than the minimum without crashing. Also this test will
37 * determine the minimum allowed stack size for the platform (as
38 * provided by the JVM error message when a very small stack is used),
39 * and then verify that the JVM can be launched with that stack size
40 * without a crash or any error messages.
41 *
42 * Note: This repo's version of the test uses the '-XX:ThreadStackSize=n'
43 * VM option for Java thread stack size testing. The jdk repo's version
44 * of the test uses the '-Xss' option.
45 */
46
47 public class TooSmallStackSize extends TestHelper {
48 /* for debugging. Normally false. */
49 static final boolean verbose = false;
50 static final String CompilerThreadStackSizeString = "CompilerThreadStackSize";
51 static final String ThreadStackSizeString = "Java thread stack size";
52 static final String VMThreadStackSizeString = "VMThreadStackSize";
53
54 static void printTestOutput(TestResult tr) {
55 System.out.println("*** exitValue = " + tr.exitValue);
56 for (String x : tr.testOutput) {
57 System.out.println(x);
58 }
59 }
60
61 /*
62 * Returns the minimum stack size this platform will allowed based on the
63 * contents of the error message the JVM outputs when too small of a
64 * stack size was used.
65 *
66 * The TestResult argument must contain the result of having already run
67 * the JVM with too small of a stack size.
68 */
69 static String getMinStackAllowed(TestResult tr) {
70 /*
71 * The JVM output will contain in one of the lines:
72 * "The CompilerThreadStackSize specified is too small. Specify at least 100k"
73 * "The Java thread stack size specified is too small. Specify at least 100k"
74 * "The VMThreadStackSize specified is too small. Specify at least 100k"
75 * Although the actual size will vary. We need to extract this size
76 * string from the output and return it.
77 */
78 String matchStr = "Specify at least ";
79 for (String x : tr.testOutput) {
80 int match_idx = x.indexOf(matchStr);
81 if (match_idx >= 0) {
82 int size_start_idx = match_idx + matchStr.length();
83 int k_start_idx = x.indexOf("k", size_start_idx);
84 // don't include the 'k'; the caller will have to
85 // add it back as needed.
86 return x.substring(size_start_idx, k_start_idx);
87 }
88 }
89
90 System.out.println("FAILED: Could not get the stack size from the output");
91 throw new RuntimeException("test fails");
92 }
93
94 /*
95 * Run the JVM with the specified stack size.
96 *
97 * Returns the minimum allowed stack size gleaned from the error message,
98 * if there is an error message. Otherwise returns the stack size passed in.
99 */
100 static String checkStack(String stackOption, String optionMesg, String stackSize) {
101 String min_stack_allowed;
102
103 if (verbose)
104 System.out.println("*** Testing " + stackOption + stackSize);
105 TestResult tr = doExec(javaCmd, stackOption + stackSize,
106 // Uncomment the following to get log output
107 // that shows actual thread creation sizes.
108 // "-Xlog:os+thread",
109 "-version");
110 if (verbose)
111 printTestOutput(tr);
112
113 if (tr.isOK()) {
114 // checkMinStackAllowed() is called with stackSize values
115 // that should be the minimum that works. This method,
116 // checkStack(), is called with stackSize values that
117 // should be too small and result in error messages.
118 // However, some platforms fix up a stackSize value that is
119 // too small into something that works so we have to allow
120 // for checkStack() calls that work.
121 System.out.println("PASSED: got no error message with " + stackOption + stackSize);
122 min_stack_allowed = stackSize;
123 } else {
124 String expect = "The " + optionMesg + " specified is too small";
125 if (verbose)
126 System.out.println("Expect='" + expect + "'");
127 if (tr.contains(expect)) {
128 System.out.println("PASSED: got expected error message with " + stackOption + stackSize);
129 min_stack_allowed = getMinStackAllowed(tr);
130 } else {
131 // Likely a crash
132 System.out.println("FAILED: Did not get expected error message with " + stackOption + stackSize);
133 throw new RuntimeException("test fails");
134 }
135 }
136
137 return min_stack_allowed;
138 }
139
140 /*
141 * Run the JVM with the minimum allowed stack size. This should always succeed.
142 */
143 static void checkMinStackAllowed(String stackOption, String optionMesg, String stackSize) {
144 if (verbose)
145 System.out.println("*** Testing " + stackOption + stackSize);
146 TestResult tr = doExec(javaCmd, stackOption + stackSize,
147 // Uncomment the following to get log output
148 // that shows actual thread creation sizes.
149 // "-Xlog:os+thread",
150 "-version");
151 if (verbose)
152 printTestOutput(tr);
153
154 if (tr.isOK()) {
155 System.out.println("PASSED: VM launched with " + stackOption + stackSize);
156 } else {
157 // Likely a crash
158 System.out.println("FAILED: VM failed to launch with " + stackOption + stackSize);
159 throw new RuntimeException("test fails");
160 }
161 }
162
163 public static void main(String... args) {
164 /*
165 * The result of a 16k stack size should be a quick exit with a complaint
166 * that the stack size is too small. However, for some win32 builds, the
167 * stack is always at least 64k, and this also sometimes is the minimum
168 * allowed size, so we won't see an error in this case.
169 *
170 * This test case will also produce a crash on some platforms if the fix
171 * for 6762191 is not yet in place.
172 */
173 checkStack("-XX:ThreadStackSize=", ThreadStackSizeString, "16");
174
175 /*
176 * Try with a 32k stack size, which is the size that the launcher will
177 * set to if you try setting to anything smaller. This should produce the same
178 * result as setting to 16k if the fix for 6762191 is in place.
179 */
180 String min_stack_allowed = checkStack("-XX:ThreadStackSize=", ThreadStackSizeString, "32");
181
182 /*
183 * Try again with a the minimum stack size that was given in the error message
184 */
185 checkMinStackAllowed("-XX:ThreadStackSize=", ThreadStackSizeString, min_stack_allowed);
186
187 /*
188 * Now redo the same tests with the compiler thread stack size:
189 */
190 checkStack("-XX:CompilerThreadStackSize=", CompilerThreadStackSizeString, "16");
191 min_stack_allowed = checkStack("-XX:CompilerThreadStackSize=", CompilerThreadStackSizeString, "32");
192 checkMinStackAllowed("-XX:CompilerThreadStackSize=", CompilerThreadStackSizeString, min_stack_allowed);
193
194 /*
195 * Now redo the same tests with the VM thread stack size:
196 */
197 checkStack("-XX:VMThreadStackSize=", VMThreadStackSizeString, "16");
198 min_stack_allowed = checkStack("-XX:VMThreadStackSize=", VMThreadStackSizeString, "32");
199 checkMinStackAllowed("-XX:VMThreadStackSize=", VMThreadStackSizeString, min_stack_allowed);
200 }
201 }