1 /*
2 * Copyright (c) 2000, 2022, 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_riscv64.LinuxRISCV64JavaThreadPDAccess;
38 import sun.jvm.hotspot.runtime.linux_ppc64.LinuxPPC64JavaThreadPDAccess;
39 import sun.jvm.hotspot.runtime.bsd_x86.BsdX86JavaThreadPDAccess;
40 import sun.jvm.hotspot.runtime.bsd_amd64.BsdAMD64JavaThreadPDAccess;
41 import sun.jvm.hotspot.runtime.bsd_aarch64.BsdAARCH64JavaThreadPDAccess;
42 import sun.jvm.hotspot.utilities.*;
43 import sun.jvm.hotspot.utilities.Observable;
44 import sun.jvm.hotspot.utilities.Observer;
45
46 class ThreadsList extends VMObject {
47 private static AddressField threadsField;
48 private static CIntegerField lengthField;
49
50 static {
51 VM.registerVMInitializedObserver((o, d) -> initialize(VM.getVM().getTypeDataBase()));
52 }
53
54 private static synchronized void initialize(TypeDataBase db) {
55 Type type = db.lookupType("ThreadsList");
56 lengthField = type.getCIntegerField("_length");
57 threadsField = type.getAddressField("_threads");
58 }
59
60 public Address getJavaThreadAddressAt(int i) {
61 Address threadAddr = threadsField.getValue(addr);
62 Address at = threadAddr.getAddressAt(VM.getVM().getAddressSize() * i);
63 return at;
64 }
65
66 public long length() {
67 return lengthField.getValue(addr);
68 }
69
70 public ThreadsList(Address addr) {
71 super(addr);
72 }
73 }
74
75 public class Threads {
76 private static JavaThreadFactory threadFactory;
77 private static AddressField threadListField;
78 private static VirtualConstructor virtualConstructor;
79 private static JavaThreadPDAccess access;
80 private static ThreadsList _list;
81
82 static {
83 VM.registerVMInitializedObserver(new Observer() {
84 public void update(Observable o, Object data) {
85 initialize(VM.getVM().getTypeDataBase());
86 }
87 });
88 }
89
90 private static synchronized void initialize(TypeDataBase db) {
91 Type type = db.lookupType("ThreadsSMRSupport");
92 threadListField = type.getAddressField("_java_thread_list");
93
94 // Instantiate appropriate platform-specific JavaThreadFactory
95 String os = VM.getVM().getOS();
96 String cpu = VM.getVM().getCPU();
97
98 access = null;
99 // FIXME: find the platform specific PD class by reflection?
100 if (os.equals("win32")) {
101 if (cpu.equals("x86")) {
102 access = new Win32X86JavaThreadPDAccess();
103 } else if (cpu.equals("amd64")) {
104 access = new Win32AMD64JavaThreadPDAccess();
105 } else if (cpu.equals("aarch64")) {
106 access = new Win32AARCH64JavaThreadPDAccess();
107 }
108 } else if (os.equals("linux")) {
109 if (cpu.equals("x86")) {
110 access = new LinuxX86JavaThreadPDAccess();
111 } else if (cpu.equals("amd64")) {
112 access = new LinuxAMD64JavaThreadPDAccess();
113 } else if (cpu.equals("ppc64")) {
114 access = new LinuxPPC64JavaThreadPDAccess();
115 } else if (cpu.equals("aarch64")) {
116 access = new LinuxAARCH64JavaThreadPDAccess();
117 } else if (cpu.equals("riscv64")) {
118 access = new LinuxRISCV64JavaThreadPDAccess();
119 } else {
120 try {
121 access = (JavaThreadPDAccess)
122 Class.forName("sun.jvm.hotspot.runtime.linux_" +
123 cpu.toLowerCase() + ".Linux" + cpu.toUpperCase() +
124 "JavaThreadPDAccess").getDeclaredConstructor().newInstance();
125 } catch (Exception e) {
126 throw new RuntimeException("OS/CPU combination " + os + "/" + cpu +
127 " not yet supported");
128 }
129 }
130 } else if (os.equals("bsd")) {
131 if (cpu.equals("x86")) {
132 access = new BsdX86JavaThreadPDAccess();
133 } else if (cpu.equals("amd64") || cpu.equals("x86_64")) {
134 access = new BsdAMD64JavaThreadPDAccess();
135 }
136 } else if (os.equals("darwin")) {
137 if (cpu.equals("amd64") || cpu.equals("x86_64")) {
138 access = new BsdAMD64JavaThreadPDAccess();
139 } else if (cpu.equals("aarch64")) {
140 access = new BsdAARCH64JavaThreadPDAccess();
141 }
142 }
143
144 if (access == null) {
145 throw new RuntimeException("OS/CPU combination " + os + "/" + cpu +
146 " not yet supported");
147 }
148
149 virtualConstructor = new VirtualConstructor(db);
150 // Add mappings for all known thread types
151 virtualConstructor.addMapping("JavaThread", JavaThread.class);
152 if (!VM.getVM().isCore()) {
153 virtualConstructor.addMapping("CompilerThread", CompilerThread.class);
154 }
155 virtualConstructor.addMapping("JvmtiAgentThread", JvmtiAgentThread.class);
156 virtualConstructor.addMapping("ServiceThread", ServiceThread.class);
157 virtualConstructor.addMapping("MonitorDeflationThread", MonitorDeflationThread.class);
158 virtualConstructor.addMapping("NotificationThread", NotificationThread.class);
159 }
160
161 public Threads() {
162 _list = VMObjectFactory.newObject(ThreadsList.class, threadListField.getValue());
163 }
164
165 /** NOTE: this returns objects of type JavaThread, CompilerThread,
166 JvmtiAgentThread, NotificationThread, MonitorDeflationThread and ServiceThread.
167 The latter four are subclasses of the former. Most operations
168 (fetching the top frame, etc.) are only allowed to be performed on
169 a "pure" JavaThread. For this reason, {@link
170 sun.jvm.hotspot.runtime.JavaThread#isJavaThread} has been
171 changed from the definition in the VM (which returns true for
172 all of these thread types) to return true for JavaThreads and
173 false for the four subclasses. FIXME: should reconsider the
174 inheritance hierarchy; see {@link
175 sun.jvm.hotspot.runtime.JavaThread#isJavaThread}. */
176 public JavaThread getJavaThreadAt(int i) {
177 if (i < _list.length()) {
178 return createJavaThreadWrapper(_list.getJavaThreadAddressAt(i));
179 }
180 return null;
181 }
182
183 public int getNumberOfThreads() {
184 return (int) _list.length();
185 }
186
187 /** Routine for instantiating appropriately-typed wrapper for a
188 JavaThread. Currently needs to be public for OopUtilities to
189 access it. */
190 public JavaThread createJavaThreadWrapper(Address threadAddr) {
191 try {
192 JavaThread thread = (JavaThread)virtualConstructor.instantiateWrapperFor(threadAddr);
193 thread.setThreadPDAccess(access);
194 return thread;
195 } catch (Exception e) {
196 throw new RuntimeException("Unable to deduce type of thread from address " + threadAddr +
197 " (expected type JavaThread, CompilerThread, MonitorDeflationThread, ServiceThread or JvmtiAgentThread)", e);
198 }
199 }
200
201 /** Memory operations */
202 public void oopsDo(AddressVisitor oopVisitor) {
203 // FIXME: add more of VM functionality
204 Threads threads = VM.getVM().getThreads();
205 for (int i = 0; i < threads.getNumberOfThreads(); i++) {
206 JavaThread thread = threads.getJavaThreadAt(i);
207 thread.oopsDo(oopVisitor);
208 }
209 }
210
211 // refer to Threads::owning_thread_from_monitor_owner
212 public JavaThread owningThreadFromMonitor(Address o) {
213 assert(!VM.getVM().getCommandLineBooleanFlag("UseFastLocking"));
214 if (o == null) return null;
215 for (int i = 0; i < getNumberOfThreads(); i++) {
216 JavaThread thread = getJavaThreadAt(i);
217 if (o.equals(thread.threadObjectAddress())) {
218 return thread;
219 }
220 }
221
222 for (int i = 0; i < getNumberOfThreads(); i++) {
223 JavaThread thread = getJavaThreadAt(i);
224 if (thread.isLockOwned(o))
225 return thread;
226 }
227 return null;
228 }
229
230 public JavaThread owningThreadFromMonitor(ObjectMonitor monitor) {
231 if (VM.getVM().getCommandLineBooleanFlag("UseFastLocking")) {
232 if (monitor.isOwnedAnonymous()) {
233 OopHandle object = monitor.object();
234 for (int i = 0; i < getNumberOfThreads(); i++) {
235 JavaThread thread = getJavaThreadAt(i);
236 if (thread.isLockOwned(object)) {
237 return thread;
238 }
239 }
240 throw new InternalError("We should have found a thread that owns the anonymous lock");
241 }
242 // Owner can only be threads at this point.
243 Address o = monitor.owner();
244 if (o == null) return null;
245 return new JavaThread(o);
246 } else {
247 return owningThreadFromMonitor(monitor.owner());
248 }
249 }
250
251 // refer to Threads::get_pending_threads
252 // Get list of Java threads that are waiting to enter the specified monitor.
253 public List<JavaThread> getPendingThreads(ObjectMonitor monitor) {
254 List<JavaThread> pendingThreads = new ArrayList<>();
255 for (int i = 0; i < getNumberOfThreads(); i++) {
256 JavaThread thread = getJavaThreadAt(i);
257 if (thread.isCompilerThread() || thread.isCodeCacheSweeperThread()) {
258 continue;
259 }
260 ObjectMonitor pending = thread.getCurrentPendingMonitor();
261 if (monitor.equals(pending)) {
262 pendingThreads.add(thread);
263 }
264 }
265 return pendingThreads;
266 }
267
268 // Get list of Java threads that have called Object.wait on the specified monitor.
269 public List<JavaThread> getWaitingThreads(ObjectMonitor monitor) {
270 List<JavaThread> pendingThreads = new ArrayList<>();
271 for (int i = 0; i < getNumberOfThreads(); i++) {
272 JavaThread thread = getJavaThreadAt(i);
273 ObjectMonitor waiting = thread.getCurrentWaitingMonitor();
274 if (monitor.equals(waiting)) {
275 pendingThreads.add(thread);
276 }
277 }
278 return pendingThreads;
279 }
280
281 // FIXME: add other accessors
282 }