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 package org.graalvm.compiler.serviceprovider;
26
27 import static java.lang.Thread.currentThread;
28
29 import java.io.IOException;
30 import java.io.InputStream;
31 import java.util.Iterator;
32 import java.util.List;
33 import java.util.ServiceConfigurationError;
34 import java.util.ServiceLoader;
35 import java.util.concurrent.atomic.AtomicLong;
36
37 import jdk.vm.ci.services.JVMCIPermission;
38 import jdk.vm.ci.services.Services;
39
40 /**
41 * Interface to functionality that abstracts over which JDK version Graal is running on.
42 */
43 public final class GraalServices {
44
45 private static int getJavaSpecificationVersion() {
46 String value = System.getProperty("java.specification.version");
47 if (value.startsWith("1.")) {
48 value = value.substring(2);
49 }
50 return Integer.parseInt(value);
51 }
52
53 /**
54 * The integer value corresponding to the value of the {@code java.specification.version} system
55 * property after any leading {@code "1."} has been stripped.
56 */
57 public static final int JAVA_SPECIFICATION_VERSION = getJavaSpecificationVersion();
58
59 /**
60 * Determines if the Java runtime is version 8 or earlier.
61 */
62 public static final boolean Java8OrEarlier = JAVA_SPECIFICATION_VERSION <= 8;
63
64 /**
65 * Determines if the Java runtime is version 11 or earlier.
66 */
67 public static final boolean Java11OrEarlier = JAVA_SPECIFICATION_VERSION <= 11;
68
69 private GraalServices() {
70 }
71
72 /**
73 * Gets an {@link Iterable} of the providers available for a given service.
74 *
75 * @throws SecurityException if on JDK8 and a security manager is present and it denies
76 * {@link JVMCIPermission}
77 */
78 public static <S> Iterable<S> load(Class<S> service) {
79 assert !service.getName().startsWith("jdk.vm.ci") : "JVMCI services must be loaded via " + Services.class.getName();
80 Iterable<S> iterable = ServiceLoader.load(service);
81 return new Iterable<>() {
82 @Override
83 public Iterator<S> iterator() {
84 Iterator<S> iterator = iterable.iterator();
85 return new Iterator<>() {
86 @Override
87 public boolean hasNext() {
88 return iterator.hasNext();
89 }
90
91 @Override
92 public S next() {
93 S provider = iterator.next();
94 // Allow Graal extensions to access JVMCI
95 openJVMCITo(provider.getClass());
96 return provider;
97 }
98
99 @Override
100 public void remove() {
101 iterator.remove();
102 }
103 };
104 }
105 };
106 }
107
108 /**
109 * Opens all JVMCI packages to the module of a given class. This relies on JVMCI already having
110 * opened all its packages to the module defining {@link GraalServices}.
111 *
112 * @param other all JVMCI packages will be opened to the module defining this class
113 */
114 static void openJVMCITo(Class<?> other) {
115 Module jvmciModule = JVMCI_MODULE;
116 Module otherModule = other.getModule();
117 if (jvmciModule != otherModule) {
118 for (String pkg : jvmciModule.getPackages()) {
119 if (!jvmciModule.isOpen(pkg, otherModule)) {
120 jvmciModule.addOpens(pkg, otherModule);
121 }
122 }
123 }
124 }
125
126 /**
127 * Gets the provider for a given service for which at most one provider must be available.
128 *
129 * @param service the service whose provider is being requested
130 * @param required specifies if an {@link InternalError} should be thrown if no provider of
131 * {@code service} is available
132 * @return the requested provider if available else {@code null}
133 * @throws SecurityException if on JDK8 and a security manager is present and it denies
134 * {@link JVMCIPermission}
135 */
136 public static <S> S loadSingle(Class<S> service, boolean required) {
137 assert !service.getName().startsWith("jdk.vm.ci") : "JVMCI services must be loaded via " + Services.class.getName();
138 Iterable<S> providers = load(service);
139 S singleProvider = null;
140 try {
141 for (Iterator<S> it = providers.iterator(); it.hasNext();) {
142 singleProvider = it.next();
143 if (it.hasNext()) {
144 S other = it.next();
145 throw new InternalError(String.format("Multiple %s providers found: %s, %s", service.getName(), singleProvider.getClass().getName(), other.getClass().getName()));
146 }
147 }
148 } catch (ServiceConfigurationError e) {
149 // If the service is required we will bail out below.
150 }
151 if (singleProvider == null) {
152 if (required) {
153 throw new InternalError(String.format("No provider for %s found", service.getName()));
154 }
155 }
156 return singleProvider;
157 }
158
159 /**
160 * Gets the class file bytes for {@code c}.
161 */
162 public static InputStream getClassfileAsStream(Class<?> c) throws IOException {
163 String classfilePath = c.getName().replace('.', '/') + ".class";
164 return c.getModule().getResourceAsStream(classfilePath);
165 }
166
167 private static final Module JVMCI_MODULE = Services.class.getModule();
168
169 /**
170 * A JVMCI package dynamically exported to trusted modules.
171 */
172 private static final String JVMCI_RUNTIME_PACKAGE = "jdk.vm.ci.runtime";
173 static {
174 assert JVMCI_MODULE.getPackages().contains(JVMCI_RUNTIME_PACKAGE);
175 }
176
177 /**
178 * Determines if invoking {@link Object#toString()} on an instance of {@code c} will only run
179 * trusted code.
180 */
181 public static boolean isToStringTrusted(Class<?> c) {
182 Module module = c.getModule();
183 Module jvmciModule = JVMCI_MODULE;
184 assert jvmciModule.getPackages().contains("jdk.vm.ci.runtime");
185 if (module == jvmciModule || jvmciModule.isOpen(JVMCI_RUNTIME_PACKAGE, module)) {
186 // Can access non-statically-exported package in JVMCI
187 return true;
188 }
189 return false;
190 }
191
192 /**
193 * Gets a unique identifier for this execution such as a process ID or a
194 * {@linkplain #getGlobalTimeStamp() fixed timestamp}.
195 */
196 public static String getExecutionID() {
197 return Long.toString(ProcessHandle.current().pid());
198 }
199
200 private static final AtomicLong globalTimeStamp = new AtomicLong();
201
202 /**
203 * Gets a time stamp for the current process. This method will always return the same value for
204 * the current VM execution.
205 */
206 public static long getGlobalTimeStamp() {
207 if (globalTimeStamp.get() == 0) {
208 globalTimeStamp.compareAndSet(0, System.currentTimeMillis());
209 }
210 return globalTimeStamp.get();
211 }
212
213 /**
214 * Returns an approximation of the total amount of memory, in bytes, allocated in heap memory
215 * for the thread of the specified ID. The returned value is an approximation because some Java
216 * virtual machine implementations may use object allocation mechanisms that result in a delay
217 * between the time an object is allocated and the time its size is recorded.
218 * <p>
219 * If the thread of the specified ID is not alive or does not exist, this method returns
220 * {@code -1}. If thread memory allocation measurement is disabled, this method returns
221 * {@code -1}. A thread is alive if it has been started and has not yet died.
222 * <p>
223 * If thread memory allocation measurement is enabled after the thread has started, the Java
224 * virtual machine implementation may choose any time up to and including the time that the
225 * capability is enabled as the point where thread memory allocation measurement starts.
226 *
227 * @param id the thread ID of a thread
228 * @return an approximation of the total memory allocated, in bytes, in heap memory for a thread
229 * of the specified ID if the thread of the specified ID exists, the thread is alive,
230 * and thread memory allocation measurement is enabled; {@code -1} otherwise.
231 *
232 * @throws IllegalArgumentException if {@code id} {@code <=} {@code 0}.
233 * @throws UnsupportedOperationException if the Java virtual machine implementation does not
234 * {@linkplain #isThreadAllocatedMemorySupported() support} thread memory allocation
235 * measurement.
236 */
237 public static long getThreadAllocatedBytes(long id) {
238 JMXService jmx = JMXService.instance;
239 if (jmx == null) {
240 throw new UnsupportedOperationException();
241 }
242 return jmx.getThreadAllocatedBytes(id);
243 }
244
245 /**
246 * Convenience method for calling {@link #getThreadAllocatedBytes(long)} with the id of the
247 * current thread.
248 */
249 public static long getCurrentThreadAllocatedBytes() {
250 return getThreadAllocatedBytes(currentThread().getId());
251 }
252
253 /**
254 * Returns the total CPU time for the current thread in nanoseconds. The returned value is of
255 * nanoseconds precision but not necessarily nanoseconds accuracy. If the implementation
256 * distinguishes between user mode time and system mode time, the returned CPU time is the
257 * amount of time that the current thread has executed in user mode or system mode.
258 *
259 * @return the total CPU time for the current thread if CPU time measurement is enabled;
260 * {@code -1} otherwise.
261 *
262 * @throws UnsupportedOperationException if the Java virtual machine does not
263 * {@linkplain #isCurrentThreadCpuTimeSupported() support} CPU time measurement for
264 * the current thread
265 */
266 public static long getCurrentThreadCpuTime() {
267 JMXService jmx = JMXService.instance;
268 if (jmx == null) {
269 throw new UnsupportedOperationException();
270 }
271 return jmx.getCurrentThreadCpuTime();
272 }
273
274 /**
275 * Determines if the Java virtual machine implementation supports thread memory allocation
276 * measurement.
277 */
278 public static boolean isThreadAllocatedMemorySupported() {
279 JMXService jmx = JMXService.instance;
280 if (jmx == null) {
281 return false;
282 }
283 return jmx.isThreadAllocatedMemorySupported();
284 }
285
286 /**
287 * Determines if the Java virtual machine supports CPU time measurement for the current thread.
288 */
289 public static boolean isCurrentThreadCpuTimeSupported() {
290 JMXService jmx = JMXService.instance;
291 if (jmx == null) {
292 return false;
293 }
294 return jmx.isCurrentThreadCpuTimeSupported();
295 }
296
297 /**
298 * Gets the input arguments passed to the Java virtual machine which does not include the
299 * arguments to the {@code main} method. This method returns an empty list if there is no input
300 * argument to the Java virtual machine.
301 * <p>
302 * Some Java virtual machine implementations may take input arguments from multiple different
303 * sources: for examples, arguments passed from the application that launches the Java virtual
304 * machine such as the 'java' command, environment variables, configuration files, etc.
305 * <p>
306 * Typically, not all command-line options to the 'java' command are passed to the Java virtual
307 * machine. Thus, the returned input arguments may not include all command-line options.
308 *
309 * @return the input arguments to the JVM or {@code null} if they are unavailable
310 */
311 public static List<String> getInputArguments() {
312 JMXService jmx = JMXService.instance;
313 if (jmx == null) {
314 return null;
315 }
316 return jmx.getInputArguments();
317 }
318 }