1 /*
2 * Copyright (c) 2016, 2017, 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 * @library /test/lib
31 * @modules java.base/jdk.internal.misc
32 * java.management
33 * @run main TooSmallStackSize
34 */
35
36 /*
37 * The primary purpose of this test is to make sure we can run with a
38 * stack smaller than the minimum without crashing. Also this test will
39 * determine the minimum allowed stack size for the platform (as
40 * provided by the JVM error message when a very small stack is used),
41 * and then verify that the JVM can be launched with that stack size
42 * without a crash or any error messages.
43 *
44 * Note: The '-Xss<size>' and '-XX:ThreadStackSize=<k-bytes>' options
45 * both control Java thread stack size. This repo's version of the test
46 * exercises the '-XX:ThreadStackSize' VM option. The jdk repo's version
47 * of the test exercises the '-Xss' option.
48 */
49
50 import jdk.test.lib.process.ProcessTools;
51 import jdk.test.lib.process.OutputAnalyzer;
52
53 public class TooSmallStackSize {
54 /* for debugging. Normally false. */
55 static final boolean verbose = false;
56 static final String CompilerThreadStackSizeString = "CompilerThreadStackSize";
57 static final String ThreadStackSizeString = "Java thread stack size";
58 static final String VMThreadStackSizeString = "VMThreadStackSize";
59
60 /*
61 * Returns the minimum stack size this platform will allowed based on the
62 * contents of the error message the JVM outputs when too small of a
63 * stack size was used.
64 *
65 * The testOutput argument must contain the result of having already run
66 * the JVM with too small of a stack size.
67 */
68 static String getMinStackAllowed(String testOutput) {
69 /*
70 * The JVM output will contain in one of the lines:
71 * "The CompilerThreadStackSize specified is too small. Specify at least 100k"
72 * "The Java thread stack size specified is too small. Specify at least 100k"
73 * "The VMThreadStackSize specified is too small. Specify at least 100k"
74 * Although the actual size will vary. We need to extract this size
75 * string from the output and return it.
76 */
77 String matchStr = "Specify at least ";
78 int match_idx = testOutput.indexOf(matchStr);
79 if (match_idx >= 0) {
80 int size_start_idx = match_idx + matchStr.length();
81 int k_start_idx = testOutput.indexOf("k", size_start_idx);
82 // don't include the 'k'; the caller will have to
83 // add it back as needed.
84 return testOutput.substring(size_start_idx, k_start_idx);
85 }
86
87 System.out.println("Expect='" + matchStr + "'");
88 System.out.println("Actual: " + testOutput);
89 System.out.println("FAILED: Could not get the stack size from the output");
90 throw new RuntimeException("test fails");
91 }
92
93 /*
94 * Run the JVM with the specified stack size.
95 *
96 * Returns the minimum allowed stack size gleaned from the error message,
97 * if there is an error message. Otherwise returns the stack size passed in.
98 */
99 static String checkStack(String stackOption, String optionMesg, String stackSize) throws Exception {
100 String min_stack_allowed;
101
102 System.out.println("*** Testing " + stackOption + stackSize);
103
104 ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(
105 stackOption + stackSize,
106 // Uncomment the following to get log output
107 // that shows actual thread creation sizes.
108 // "-Xlog:os+thread",
109 "-version");
110
111 OutputAnalyzer output = new OutputAnalyzer(pb.start());
112
113 if (verbose) {
114 System.out.println("stdout: " + output.getStdout());
115 }
116
117 if (output.getExitValue() == 0) {
118 // checkMinStackAllowed() is called with stackSize values
119 // that should be the minimum that works. This method,
120 // checkStack(), is called with stackSize values that
121 // should be too small and result in error messages.
122 // However, some platforms fix up a stackSize value that is
123 // too small into something that works so we have to allow
124 // for checkStack() calls that work.
125 System.out.println("PASSED: got exit_code == 0 with " + stackOption + stackSize);
126 min_stack_allowed = stackSize;
127 } else {
128 String expect = "The " + optionMesg + " specified is too small";
129 if (verbose) {
130 System.out.println("Expect='" + expect + "'");
131 }
132 output.shouldContain(expect);
133 min_stack_allowed = getMinStackAllowed(output.getStdout());
134
135 System.out.println("PASSED: got expected error message with " + stackOption + stackSize);
136 }
137
138 return min_stack_allowed;
139 }
140
141 /*
142 * Run the JVM with the minimum allowed stack size. This should always succeed.
143 */
144 static void checkMinStackAllowed(String stackOption, String optionMesg, String stackSize) throws Exception {
145 System.out.println("*** Testing " + stackOption + stackSize);
146
147 ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(
148 stackOption + stackSize,
149 // Uncomment the following to get log output
150 // that shows actual thread creation sizes.
151 // "-Xlog:os+thread",
152 "-version");
153
154 OutputAnalyzer output = new OutputAnalyzer(pb.start());
155 output.shouldHaveExitValue(0);
156
157 System.out.println("PASSED: VM launched with " + stackOption + stackSize);
158 }
159
160 public static void main(String... args) throws Exception {
161 /*
162 * The result of a 16k stack size should be a quick exit with a complaint
163 * that the stack size is too small. However, for some win32 builds, the
164 * stack is always at least 64k, and this also sometimes is the minimum
165 * allowed size, so we won't see an error in this case.
166 *
167 * This test case will also produce a crash on some platforms if the fix
168 * for 6762191 is not yet in place.
169 */
170 checkStack("-XX:ThreadStackSize=", ThreadStackSizeString, "16");
171
172 /*
173 * Try with a 64k stack size, which is the size that the launcher will
174 * set to if you try setting to anything smaller. This should produce the same
175 * result as setting to 16k if the fix for 6762191 is in place.
176 */
177 String min_stack_allowed = checkStack("-XX:ThreadStackSize=", ThreadStackSizeString, "64");
178
179 /*
180 * Try again with a the minimum stack size that was given in the error message
181 */
182 checkMinStackAllowed("-XX:ThreadStackSize=", ThreadStackSizeString, min_stack_allowed);
183
184 /*
185 * Now try with a stack size that is not page aligned.
186 */
187 checkMinStackAllowed("-XX:ThreadStackSize=", ThreadStackSizeString, "513");
188
189 /*
190 * Now redo the same tests with the compiler thread stack size:
191 */
192 checkStack("-XX:CompilerThreadStackSize=", CompilerThreadStackSizeString, "16");
193 min_stack_allowed = checkStack("-XX:CompilerThreadStackSize=", CompilerThreadStackSizeString, "64");
194 checkMinStackAllowed("-XX:CompilerThreadStackSize=", CompilerThreadStackSizeString, min_stack_allowed);
195 checkMinStackAllowed("-XX:CompilerThreadStackSize=", CompilerThreadStackSizeString, "513");
196
197 /*
198 * Now redo the same tests with the VM thread stack size:
199 */
200 checkStack("-XX:VMThreadStackSize=", VMThreadStackSizeString, "16");
201 min_stack_allowed = checkStack("-XX:VMThreadStackSize=", VMThreadStackSizeString, "64");
202 checkMinStackAllowed("-XX:VMThreadStackSize=", VMThreadStackSizeString, min_stack_allowed);
203 checkMinStackAllowed("-XX:VMThreadStackSize=", VMThreadStackSizeString, "513");
204 }
205 }