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 * @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: This repo's version of the test uses the '-XX:ThreadStackSize=n'
45 * VM option for Java thread stack size testing. The jdk repo's version
46 * of the test uses the '-Xss' option.
47 */
48
49 import jdk.test.lib.process.ProcessTools;
50 import jdk.test.lib.process.OutputAnalyzer;
51
52 public class TooSmallStackSize {
53 /* for debugging. Normally false. */
54 static final boolean verbose = false;
55 static final String CompilerThreadStackSizeString = "CompilerThreadStackSize";
56 static final String ThreadStackSizeString = "Java thread stack size";
57 static final String VMThreadStackSizeString = "VMThreadStackSize";
58
59 /*
60 * Returns the minimum stack size this platform will allowed based on the
61 * contents of the error message the JVM outputs when too small of a
62 * stack size was used.
63 *
64 * The testOutput argument must contain the result of having already run
65 * the JVM with too small of a stack size.
66 */
67 static String getMinStackAllowed(String testOutput) {
68 /*
69 * The JVM output will contain in one of the lines:
70 * "The CompilerThreadStackSize specified is too small. Specify at least 100k"
71 * "The Java thread stack size specified is too small. Specify at least 100k"
72 * "The VMThreadStackSize specified is too small. Specify at least 100k"
73 * Although the actual size will vary. We need to extract this size
74 * string from the output and return it.
75 */
76 String matchStr = "Specify at least ";
77 int match_idx = testOutput.indexOf(matchStr);
78 if (match_idx >= 0) {
79 int size_start_idx = match_idx + matchStr.length();
80 int k_start_idx = testOutput.indexOf("k", size_start_idx);
81 // don't include the 'k'; the caller will have to
82 // add it back as needed.
83 return testOutput.substring(size_start_idx, k_start_idx);
84 }
85
86 System.out.println("FAILED: Could not get the stack size from the output");
87 throw new RuntimeException("test fails");
88 }
89
90 /*
91 * Run the JVM with the specified stack size.
92 *
93 * Returns the minimum allowed stack size gleaned from the error message,
94 * if there is an error message. Otherwise returns the stack size passed in.
95 */
96 static String checkStack(String stackOption, String optionMesg, String stackSize) throws Exception {
97 String min_stack_allowed;
98
99 System.out.println("*** Testing " + stackOption + stackSize);
100
101 ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(
102 stackOption + stackSize,
103 // Uncomment the following to get log output
104 // that shows actual thread creation sizes.
105 // "-Xlog:os+thread",
106 "-version");
107
108 OutputAnalyzer output = new OutputAnalyzer(pb.start());
109
110 if (verbose) {
111 System.out.println("stdout: " + output.getStdout());
112 }
113
114 if (output.getExitValue() == 0) {
115 // checkMinStackAllowed() is called with stackSize values
116 // that should be the minimum that works. This method,
117 // checkStack(), is called with stackSize values that
118 // should be too small and result in error messages.
119 // However, some platforms fix up a stackSize value that is
120 // too small into something that works so we have to allow
121 // for checkStack() calls that work.
122 System.out.println("PASSED: got exit_code == 0 with " + stackOption + stackSize);
123 min_stack_allowed = stackSize;
124 } else {
125 String expect = "The " + optionMesg + " specified is too small";
126 if (verbose) {
127 System.out.println("Expect='" + expect + "'");
128 }
129 output.shouldContain(expect);
130 min_stack_allowed = getMinStackAllowed(output.getStdout());
131
132 System.out.println("PASSED: got expected error message with " + stackOption + stackSize);
133 }
134
135 return min_stack_allowed;
136 }
137
138 /*
139 * Run the JVM with the minimum allowed stack size. This should always succeed.
140 */
141 static void checkMinStackAllowed(String stackOption, String optionMesg, String stackSize) throws Exception {
142 System.out.println("*** Testing " + stackOption + stackSize);
143
144 ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(
145 stackOption + stackSize,
146 // Uncomment the following to get log output
147 // that shows actual thread creation sizes.
148 // "-Xlog:os+thread",
149 "-version");
150
151 OutputAnalyzer output = new OutputAnalyzer(pb.start());
152 output.shouldHaveExitValue(0);
153
154 System.out.println("PASSED: VM launched with " + stackOption + stackSize);
155 }
156
157 public static void main(String... args) throws Exception {
158 /*
159 * The result of a 16k stack size should be a quick exit with a complaint
160 * that the stack size is too small. However, for some win32 builds, the
161 * stack is always at least 64k, and this also sometimes is the minimum
162 * allowed size, so we won't see an error in this case.
163 *
164 * This test case will also produce a crash on some platforms if the fix
165 * for 6762191 is not yet in place.
166 */
167 checkStack("-XX:ThreadStackSize=", ThreadStackSizeString, "16");
168
169 /*
170 * Try with a 32k stack size, which is the size that the launcher will
171 * set to if you try setting to anything smaller. This should produce the same
172 * result as setting to 16k if the fix for 6762191 is in place.
173 */
174 String min_stack_allowed = checkStack("-XX:ThreadStackSize=", ThreadStackSizeString, "32");
175
176 /*
177 * Try again with a the minimum stack size that was given in the error message
178 */
179 checkMinStackAllowed("-XX:ThreadStackSize=", ThreadStackSizeString, min_stack_allowed);
180
181 /*
182 * Now redo the same tests with the compiler thread stack size:
183 */
184 checkStack("-XX:CompilerThreadStackSize=", CompilerThreadStackSizeString, "16");
185 min_stack_allowed = checkStack("-XX:CompilerThreadStackSize=", CompilerThreadStackSizeString, "32");
186 checkMinStackAllowed("-XX:CompilerThreadStackSize=", CompilerThreadStackSizeString, min_stack_allowed);
187
188 /*
189 * Now redo the same tests with the VM thread stack size:
190 */
191 checkStack("-XX:VMThreadStackSize=", VMThreadStackSizeString, "16");
192 min_stack_allowed = checkStack("-XX:VMThreadStackSize=", VMThreadStackSizeString, "32");
193 checkMinStackAllowed("-XX:VMThreadStackSize=", VMThreadStackSizeString, min_stack_allowed);
194 }
195 }