1 /*
2 * Copyright (c) 2000, 2021, 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 sun.jvm.hotspot.runtime;
26
27 import java.util.*;
28
29 import sun.jvm.hotspot.debugger.*;
30 import sun.jvm.hotspot.types.*;
31 import sun.jvm.hotspot.runtime.win32_x86.Win32X86JavaThreadPDAccess;
32 import sun.jvm.hotspot.runtime.win32_amd64.Win32AMD64JavaThreadPDAccess;
33 import sun.jvm.hotspot.runtime.win32_aarch64.Win32AARCH64JavaThreadPDAccess;
34 import sun.jvm.hotspot.runtime.linux_x86.LinuxX86JavaThreadPDAccess;
35 import sun.jvm.hotspot.runtime.linux_amd64.LinuxAMD64JavaThreadPDAccess;
36 import sun.jvm.hotspot.runtime.linux_aarch64.LinuxAARCH64JavaThreadPDAccess;
37 import sun.jvm.hotspot.runtime.linux_ppc64.LinuxPPC64JavaThreadPDAccess;
38 import sun.jvm.hotspot.runtime.bsd_x86.BsdX86JavaThreadPDAccess;
39 import sun.jvm.hotspot.runtime.bsd_amd64.BsdAMD64JavaThreadPDAccess;
40 import sun.jvm.hotspot.runtime.bsd_aarch64.BsdAARCH64JavaThreadPDAccess;
41 import sun.jvm.hotspot.utilities.*;
42 import sun.jvm.hotspot.utilities.Observable;
43 import sun.jvm.hotspot.utilities.Observer;
44
45 class ThreadsList extends VMObject {
46 private static AddressField threadsField;
47 private static CIntegerField lengthField;
48
49 static {
50 VM.registerVMInitializedObserver((o, d) -> initialize(VM.getVM().getTypeDataBase()));
51 }
52
53 private static synchronized void initialize(TypeDataBase db) {
54 Type type = db.lookupType("ThreadsList");
55 lengthField = type.getCIntegerField("_length");
56 threadsField = type.getAddressField("_threads");
57 }
58
59 public Address getJavaThreadAddressAt(int i) {
60 Address threadAddr = threadsField.getValue(addr);
61 Address at = threadAddr.getAddressAt(VM.getVM().getAddressSize() * i);
62 return at;
63 }
64
65 public long length() {
66 return lengthField.getValue(addr);
67 }
68
69 public ThreadsList(Address addr) {
70 super(addr);
71 }
72 }
73
74 public class Threads {
75 private static JavaThreadFactory threadFactory;
76 private static AddressField threadListField;
77 private static VirtualConstructor virtualConstructor;
78 private static JavaThreadPDAccess access;
79 private static ThreadsList _list;
80
81 static {
82 VM.registerVMInitializedObserver(new Observer() {
83 public void update(Observable o, Object data) {
84 initialize(VM.getVM().getTypeDataBase());
85 }
86 });
87 }
88
89 private static synchronized void initialize(TypeDataBase db) {
90 Type type = db.lookupType("ThreadsSMRSupport");
91 threadListField = type.getAddressField("_java_thread_list");
92
93 // Instantiate appropriate platform-specific JavaThreadFactory
94 String os = VM.getVM().getOS();
95 String cpu = VM.getVM().getCPU();
96
97 access = null;
98 // FIXME: find the platform specific PD class by reflection?
99 if (os.equals("win32")) {
100 if (cpu.equals("x86")) {
101 access = new Win32X86JavaThreadPDAccess();
102 } else if (cpu.equals("amd64")) {
103 access = new Win32AMD64JavaThreadPDAccess();
104 } else if (cpu.equals("aarch64")) {
105 access = new Win32AARCH64JavaThreadPDAccess();
106 }
107 } else if (os.equals("linux")) {
108 if (cpu.equals("x86")) {
109 access = new LinuxX86JavaThreadPDAccess();
110 } else if (cpu.equals("amd64")) {
111 access = new LinuxAMD64JavaThreadPDAccess();
112 } else if (cpu.equals("ppc64")) {
113 access = new LinuxPPC64JavaThreadPDAccess();
114 } else if (cpu.equals("aarch64")) {
115 access = new LinuxAARCH64JavaThreadPDAccess();
116 } else {
117 try {
118 access = (JavaThreadPDAccess)
119 Class.forName("sun.jvm.hotspot.runtime.linux_" +
120 cpu.toLowerCase() + ".Linux" + cpu.toUpperCase() +
121 "JavaThreadPDAccess").getDeclaredConstructor().newInstance();
122 } catch (Exception e) {
123 throw new RuntimeException("OS/CPU combination " + os + "/" + cpu +
124 " not yet supported");
125 }
126 }
127 } else if (os.equals("bsd")) {
128 if (cpu.equals("x86")) {
129 access = new BsdX86JavaThreadPDAccess();
130 } else if (cpu.equals("amd64") || cpu.equals("x86_64")) {
131 access = new BsdAMD64JavaThreadPDAccess();
132 }
133 } else if (os.equals("darwin")) {
134 if (cpu.equals("amd64") || cpu.equals("x86_64")) {
135 access = new BsdAMD64JavaThreadPDAccess();
136 } else if (cpu.equals("aarch64")) {
137 access = new BsdAARCH64JavaThreadPDAccess();
138 }
139 }
140
141 if (access == null) {
142 throw new RuntimeException("OS/CPU combination " + os + "/" + cpu +
143 " not yet supported");
144 }
145
146 virtualConstructor = new VirtualConstructor(db);
147 // Add mappings for all known thread types
148 virtualConstructor.addMapping("JavaThread", JavaThread.class);
149 if (!VM.getVM().isCore()) {
150 virtualConstructor.addMapping("CompilerThread", CompilerThread.class);
151 virtualConstructor.addMapping("CodeCacheSweeperThread", CodeCacheSweeperThread.class);
152 }
153 virtualConstructor.addMapping("JvmtiAgentThread", JvmtiAgentThread.class);
154 virtualConstructor.addMapping("ServiceThread", ServiceThread.class);
155 virtualConstructor.addMapping("MonitorDeflationThread", MonitorDeflationThread.class);
156 virtualConstructor.addMapping("NotificationThread", NotificationThread.class);
157 }
158
159 public Threads() {
160 _list = VMObjectFactory.newObject(ThreadsList.class, threadListField.getValue());
161 }
162
163 /** NOTE: this returns objects of type JavaThread, CompilerThread,
164 JvmtiAgentThread, NotificationThread, MonitorDeflationThread and ServiceThread.
165 The latter four are subclasses of the former. Most operations
166 (fetching the top frame, etc.) are only allowed to be performed on
167 a "pure" JavaThread. For this reason, {@link
168 sun.jvm.hotspot.runtime.JavaThread#isJavaThread} has been
169 changed from the definition in the VM (which returns true for
170 all of these thread types) to return true for JavaThreads and
171 false for the four subclasses. FIXME: should reconsider the
172 inheritance hierarchy; see {@link
173 sun.jvm.hotspot.runtime.JavaThread#isJavaThread}. */
174 public JavaThread getJavaThreadAt(int i) {
175 if (i < _list.length()) {
176 return createJavaThreadWrapper(_list.getJavaThreadAddressAt(i));
177 }
178 return null;
179 }
180
181 public int getNumberOfThreads() {
182 return (int) _list.length();
183 }
184
185 /** Routine for instantiating appropriately-typed wrapper for a
186 JavaThread. Currently needs to be public for OopUtilities to
187 access it. */
188 public JavaThread createJavaThreadWrapper(Address threadAddr) {
189 try {
190 JavaThread thread = (JavaThread)virtualConstructor.instantiateWrapperFor(threadAddr);
191 thread.setThreadPDAccess(access);
192 return thread;
193 } catch (Exception e) {
194 throw new RuntimeException("Unable to deduce type of thread from address " + threadAddr +
195 " (expected type JavaThread, CompilerThread, MonitorDeflationThread, ServiceThread, JvmtiAgentThread or CodeCacheSweeperThread)", e);
196 }
197 }
198
199 /** Memory operations */
200 public void oopsDo(AddressVisitor oopVisitor) {
201 // FIXME: add more of VM functionality
202 Threads threads = VM.getVM().getThreads();
203 for (int i = 0; i < threads.getNumberOfThreads(); i++) {
204 JavaThread thread = threads.getJavaThreadAt(i);
205 thread.oopsDo(oopVisitor);
206 }
207 }
208
209 // refer to Threads::owning_thread_from_monitor_owner
210 public JavaThread owningThreadFromMonitor(Address o) {
211 assert(!VM.getVM().getCommandLineBooleanFlag("UseFastLocking"));
212 if (o == null) return null;
213 for (int i = 0; i < getNumberOfThreads(); i++) {
214 JavaThread thread = getJavaThreadAt(i);
215 if (o.equals(thread.threadObjectAddress())) {
216 return thread;
217 }
218 }
219
220 for (int i = 0; i < getNumberOfThreads(); i++) {
221 JavaThread thread = getJavaThreadAt(i);
222 if (thread.isLockOwned(o))
223 return thread;
224 }
225 return null;
226 }
227
228 public JavaThread owningThreadFromMonitor(ObjectMonitor monitor) {
229 if (VM.getVM().getCommandLineBooleanFlag("UseFastLocking")) {
230 if (monitor.isOwnedAnonymous()) {
231 OopHandle object = monitor.object();
232 for (int i = 0; i < getNumberOfThreads(); i++) {
233 JavaThread thread = getJavaThreadAt(i);
234 if (thread.isLockOwned(object)) {
235 return thread;
236 }
237 }
238 throw new InternalError("We should have found a thread that owns the anonymous lock");
239 }
240 // Owner can only be threads at this point.
241 Address o = monitor.owner();
242 if (o == null) return null;
243 return new JavaThread(o);
244 } else {
245 return owningThreadFromMonitor(monitor.owner());
246 }
247 }
248
249 // refer to Threads::get_pending_threads
250 // Get list of Java threads that are waiting to enter the specified monitor.
251 public List<JavaThread> getPendingThreads(ObjectMonitor monitor) {
252 List<JavaThread> pendingThreads = new ArrayList<>();
253 for (int i = 0; i < getNumberOfThreads(); i++) {
254 JavaThread thread = getJavaThreadAt(i);
255 if (thread.isCompilerThread() || thread.isCodeCacheSweeperThread()) {
256 continue;
257 }
258 ObjectMonitor pending = thread.getCurrentPendingMonitor();
259 if (monitor.equals(pending)) {
260 pendingThreads.add(thread);
261 }
262 }
263 return pendingThreads;
264 }
265
266 // Get list of Java threads that have called Object.wait on the specified monitor.
267 public List<JavaThread> getWaitingThreads(ObjectMonitor monitor) {
268 List<JavaThread> pendingThreads = new ArrayList<>();
269 for (int i = 0; i < getNumberOfThreads(); i++) {
270 JavaThread thread = getJavaThreadAt(i);
271 ObjectMonitor waiting = thread.getCurrentWaitingMonitor();
272 if (monitor.equals(waiting)) {
273 pendingThreads.add(thread);
274 }
275 }
276 return pendingThreads;
277 }
278
279 // FIXME: add other accessors
280 }