1 /*
2 * Copyright (c) 1997, 2025, 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 #include "gc/shared/gc_globals.hpp"
26 #include "logging/log.hpp"
27 #include "logging/logStream.hpp"
28 #include "memory/resourceArea.hpp"
29 #include "memory/universe.hpp"
30 #include "runtime/javaThread.hpp"
31 #include "runtime/mutexLocker.hpp"
32 #include "runtime/safepoint.hpp"
33 #include "runtime/vmThread.hpp"
34 #include "utilities/vmError.hpp"
35
36 // Mutexes used in the VM (see comment in mutexLocker.hpp):
37
38 Mutex* NMethodState_lock = nullptr;
39 Monitor* SystemDictionary_lock = nullptr;
40 Mutex* InvokeMethodTypeTable_lock = nullptr;
41 Monitor* InvokeMethodIntrinsicTable_lock = nullptr;
42 Mutex* SharedDictionary_lock = nullptr;
43 Monitor* ClassInitError_lock = nullptr;
44 Mutex* Module_lock = nullptr;
45 Mutex* CompiledIC_lock = nullptr;
46 Mutex* VMStatistic_lock = nullptr;
47 Mutex* JmethodIdCreation_lock = nullptr;
48 Mutex* JfieldIdCreation_lock = nullptr;
49 Mutex* JvmtiThreadState_lock = nullptr;
50 Monitor* EscapeBarrier_lock = nullptr;
51 Monitor* JvmtiVTMSTransition_lock = nullptr;
52 Monitor* Heap_lock = nullptr;
53 #if INCLUDE_PARALLELGC
54 Mutex* PSOldGenExpand_lock = nullptr;
55 #endif
56 Mutex* AdapterHandlerLibrary_lock = nullptr;
57 Mutex* SignatureHandlerLibrary_lock = nullptr;
58 Mutex* VtableStubs_lock = nullptr;
59 Mutex* SymbolArena_lock = nullptr;
60 Monitor* StringDedup_lock = nullptr;
61 Mutex* StringDedupIntern_lock = nullptr;
62 Monitor* CodeCache_lock = nullptr;
63 Mutex* TouchedMethodLog_lock = nullptr;
64 Mutex* RetData_lock = nullptr;
65 Monitor* VMOperation_lock = nullptr;
66 Monitor* ThreadsLockThrottle_lock = nullptr;
67 Monitor* Threads_lock = nullptr;
68 Mutex* NonJavaThreadsList_lock = nullptr;
69 Mutex* NonJavaThreadsListSync_lock = nullptr;
70 Monitor* CGC_lock = nullptr;
71 Monitor* STS_lock = nullptr;
72 Monitor* G1OldGCCount_lock = nullptr;
73 Mutex* G1RareEvent_lock = nullptr;
74 Mutex* G1DetachedRefinementStats_lock = nullptr;
75 Mutex* MarkStackFreeList_lock = nullptr;
76 Mutex* MarkStackChunkList_lock = nullptr;
77 Mutex* MonitoringSupport_lock = nullptr;
78 Monitor* ConcurrentGCBreakpoints_lock = nullptr;
79 Mutex* Compile_lock = nullptr;
80 Monitor* MethodCompileQueue_lock = nullptr;
81 Monitor* CompileThread_lock = nullptr;
82 Monitor* Compilation_lock = nullptr;
83 Mutex* CompileTaskAlloc_lock = nullptr;
84 Mutex* CompileStatistics_lock = nullptr;
85 Mutex* DirectivesStack_lock = nullptr;
86 Monitor* Terminator_lock = nullptr;
87 Monitor* InitCompleted_lock = nullptr;
88 Monitor* BeforeExit_lock = nullptr;
89 Monitor* Notify_lock = nullptr;
90 Mutex* ExceptionCache_lock = nullptr;
91 #ifndef PRODUCT
92 Mutex* FullGCALot_lock = nullptr;
93 #endif
94
95 Mutex* tty_lock = nullptr;
96
97 Mutex* RawMonitor_lock = nullptr;
98 Mutex* PerfDataMemAlloc_lock = nullptr;
99 Mutex* PerfDataManager_lock = nullptr;
100
101 Mutex* FreeList_lock = nullptr;
102 Mutex* OldSets_lock = nullptr;
103 Mutex* Uncommit_lock = nullptr;
104 Monitor* RootRegionScan_lock = nullptr;
105
106 Mutex* Management_lock = nullptr;
107 Monitor* MonitorDeflation_lock = nullptr;
108 Monitor* Service_lock = nullptr;
109 Monitor* Notification_lock = nullptr;
110 Monitor* PeriodicTask_lock = nullptr;
111 Monitor* RedefineClasses_lock = nullptr;
112 Mutex* Verify_lock = nullptr;
113
114 #if INCLUDE_JFR
115 Mutex* JfrStacktrace_lock = nullptr;
116 Monitor* JfrMsg_lock = nullptr;
117 Mutex* JfrBuffer_lock = nullptr;
118 Monitor* JfrThreadSampler_lock = nullptr;
119 #endif
120
121 Mutex* CodeHeapStateAnalytics_lock = nullptr;
122
123 Mutex* ExternalsRecorder_lock = nullptr;
124
125 Monitor* ContinuationRelativize_lock = nullptr;
126
127 Mutex* Metaspace_lock = nullptr;
128 Monitor* MetaspaceCritical_lock = nullptr;
129 Mutex* ClassLoaderDataGraph_lock = nullptr;
130 Monitor* ThreadsSMRDelete_lock = nullptr;
131 Mutex* ThreadIdTableCreate_lock = nullptr;
132 Mutex* SharedDecoder_lock = nullptr;
133 Mutex* DCmdFactory_lock = nullptr;
134 Mutex* NMTQuery_lock = nullptr;
135 Mutex* NMTCompilationCostHistory_lock = nullptr;
136 Mutex* NmtVirtualMemory_lock = nullptr;
137
138 #if INCLUDE_CDS
139 #if INCLUDE_JVMTI
140 Mutex* CDSClassFileStream_lock = nullptr;
141 #endif
142 Mutex* DumpTimeTable_lock = nullptr;
143 Mutex* CDSLambda_lock = nullptr;
144 Mutex* DumpRegion_lock = nullptr;
145 Mutex* ClassListFile_lock = nullptr;
146 Mutex* UnregisteredClassesTable_lock= nullptr;
147 Mutex* LambdaFormInvokers_lock = nullptr;
148 Mutex* ScratchObjects_lock = nullptr;
149 #endif // INCLUDE_CDS
150 Mutex* Bootclasspath_lock = nullptr;
151
152 #if INCLUDE_JVMCI
153 Monitor* JVMCI_lock = nullptr;
154 Monitor* JVMCIRuntime_lock = nullptr;
155 #endif
156
157 // Only one RecursiveMutex
158 RecursiveMutex* MultiArray_lock = nullptr;
159
160 #ifdef ASSERT
161 void assert_locked_or_safepoint(const Mutex* lock) {
162 if (DebuggingContext::is_enabled() || VMError::is_error_reported()) return;
163 // check if this thread owns the lock (common case)
164 assert(lock != nullptr, "Need non-null lock");
165 if (lock->owned_by_self()) return;
166 if (SafepointSynchronize::is_at_safepoint()) return;
167 if (!Universe::is_fully_initialized()) return;
168 fatal("must own lock %s", lock->name());
169 }
170
171 // a stronger assertion than the above
172 void assert_lock_strong(const Mutex* lock) {
173 if (DebuggingContext::is_enabled() || VMError::is_error_reported()) return;
174 assert(lock != nullptr, "Need non-null lock");
175 if (lock->owned_by_self()) return;
176 fatal("must own lock %s", lock->name());
177 }
178 #endif
179
180 #define MUTEX_STORAGE_NAME(name) name##_storage
181 #define MUTEX_STORAGE(name, type) alignas(type) static uint8_t MUTEX_STORAGE_NAME(name)[sizeof(type)]
182 #define MUTEX_DEF(name, type, pri, ...) { \
183 assert(name == nullptr, "Mutex/Monitor initialized twice"); \
184 MUTEX_STORAGE(name, type); \
185 name = ::new(static_cast<void*>(MUTEX_STORAGE_NAME(name))) type((pri), #name, ##__VA_ARGS__); \
186 Mutex::add_mutex(name); \
187 }
188 #define MUTEX_DEFN(name, type, pri, ...) MUTEX_DEF(name, type, Mutex::pri, ##__VA_ARGS__)
189
190 // Specify relative ranked lock
191 #ifdef ASSERT
192 #define MUTEX_DEFL(name, type, held_lock, ...) MUTEX_DEF(name, type, (held_lock)->rank() - 1, ##__VA_ARGS__)
193 #else
194 #define MUTEX_DEFL(name, type, held_lock, ...) MUTEX_DEFN(name, type, safepoint, ##__VA_ARGS__)
195 #endif
196
197 // Using Padded subclasses to prevent false sharing of these global monitors and mutexes.
198 void mutex_init() {
199 MUTEX_DEFN(tty_lock , PaddedMutex , tty); // allow to lock in VM
200
201 MUTEX_DEFN(STS_lock , PaddedMonitor, nosafepoint);
202
203 if (UseG1GC) {
204 MUTEX_DEFN(CGC_lock , PaddedMonitor, nosafepoint);
205
206 MUTEX_DEFN(G1DetachedRefinementStats_lock, PaddedMutex , nosafepoint-2);
207
208 MUTEX_DEFN(FreeList_lock , PaddedMutex , service-1);
209 MUTEX_DEFN(OldSets_lock , PaddedMutex , nosafepoint);
210 MUTEX_DEFN(Uncommit_lock , PaddedMutex , service-2);
211 MUTEX_DEFN(RootRegionScan_lock , PaddedMonitor, nosafepoint-1);
212
213 MUTEX_DEFN(MarkStackFreeList_lock , PaddedMutex , nosafepoint);
214 MUTEX_DEFN(MarkStackChunkList_lock , PaddedMutex , nosafepoint);
215 }
216 MUTEX_DEFN(MonitoringSupport_lock , PaddedMutex , service-1); // used for serviceability monitoring support
217
218 MUTEX_DEFN(StringDedup_lock , PaddedMonitor, nosafepoint);
219 MUTEX_DEFN(StringDedupIntern_lock , PaddedMutex , nosafepoint);
220 MUTEX_DEFN(RawMonitor_lock , PaddedMutex , nosafepoint-1);
221
222 MUTEX_DEFN(Metaspace_lock , PaddedMutex , nosafepoint-3);
223 MUTEX_DEFN(MetaspaceCritical_lock , PaddedMonitor, nosafepoint-1);
224
225 MUTEX_DEFN(MonitorDeflation_lock , PaddedMonitor, nosafepoint); // used for monitor deflation thread operations
226 MUTEX_DEFN(Service_lock , PaddedMonitor, service); // used for service thread operations
227 MUTEX_DEFN(Notification_lock , PaddedMonitor, service); // used for notification thread operations
228
229 MUTEX_DEFN(JmethodIdCreation_lock , PaddedMutex , nosafepoint-2); // used for creating jmethodIDs.
230 MUTEX_DEFN(InvokeMethodTypeTable_lock , PaddedMutex , safepoint);
231 MUTEX_DEFN(InvokeMethodIntrinsicTable_lock , PaddedMonitor, safepoint);
232 MUTEX_DEFN(AdapterHandlerLibrary_lock , PaddedMutex , safepoint);
233 MUTEX_DEFN(SharedDictionary_lock , PaddedMutex , safepoint);
234 MUTEX_DEFN(VMStatistic_lock , PaddedMutex , safepoint);
235 MUTEX_DEFN(SignatureHandlerLibrary_lock , PaddedMutex , safepoint);
236 MUTEX_DEFN(SymbolArena_lock , PaddedMutex , nosafepoint);
237 MUTEX_DEFN(ExceptionCache_lock , PaddedMutex , safepoint);
238 #ifndef PRODUCT
239 MUTEX_DEFN(FullGCALot_lock , PaddedMutex , safepoint); // a lock to make FullGCALot MT safe
240 #endif
241 MUTEX_DEFN(BeforeExit_lock , PaddedMonitor, safepoint);
242
243 MUTEX_DEFN(NonJavaThreadsList_lock , PaddedMutex , nosafepoint-1);
244 MUTEX_DEFN(NonJavaThreadsListSync_lock , PaddedMutex , nosafepoint);
245
246 MUTEX_DEFN(RetData_lock , PaddedMutex , safepoint);
247 MUTEX_DEFN(Terminator_lock , PaddedMonitor, safepoint, true);
248 MUTEX_DEFN(InitCompleted_lock , PaddedMonitor, nosafepoint);
249 MUTEX_DEFN(Notify_lock , PaddedMonitor, safepoint, true);
250
251 MUTEX_DEFN(JfieldIdCreation_lock , PaddedMutex , safepoint);
252
253 MUTEX_DEFN(CompiledIC_lock , PaddedMutex , nosafepoint); // locks VtableStubs_lock
254 MUTEX_DEFN(MethodCompileQueue_lock , PaddedMonitor, safepoint);
255 MUTEX_DEFN(CompileStatistics_lock , PaddedMutex , safepoint);
256 MUTEX_DEFN(DirectivesStack_lock , PaddedMutex , nosafepoint);
257
258 MUTEX_DEFN(JvmtiVTMSTransition_lock , PaddedMonitor, safepoint); // used for Virtual Thread Mount State transition management
259 MUTEX_DEFN(EscapeBarrier_lock , PaddedMonitor, nosafepoint); // Used to synchronize object reallocation/relocking triggered by JVMTI
260 MUTEX_DEFN(Management_lock , PaddedMutex , safepoint); // used for JVM management
261
262 MUTEX_DEFN(ConcurrentGCBreakpoints_lock , PaddedMonitor, safepoint, true);
263 MUTEX_DEFN(TouchedMethodLog_lock , PaddedMutex , safepoint);
264
265 MUTEX_DEFN(CompileThread_lock , PaddedMonitor, safepoint);
266 MUTEX_DEFN(PeriodicTask_lock , PaddedMonitor, safepoint, true);
267 MUTEX_DEFN(RedefineClasses_lock , PaddedMonitor, safepoint);
268 MUTEX_DEFN(Verify_lock , PaddedMutex , safepoint);
269 MUTEX_DEFN(ClassLoaderDataGraph_lock , PaddedMutex , safepoint);
270
271 if (WhiteBoxAPI) {
272 MUTEX_DEFN(Compilation_lock , PaddedMonitor, nosafepoint);
273 }
274
275 #if INCLUDE_JFR
276 MUTEX_DEFN(JfrBuffer_lock , PaddedMutex , event);
277 MUTEX_DEFN(JfrMsg_lock , PaddedMonitor, event);
278 MUTEX_DEFN(JfrStacktrace_lock , PaddedMutex , event);
279 MUTEX_DEFN(JfrThreadSampler_lock , PaddedMonitor, nosafepoint);
280 #endif
281
282 MUTEX_DEFN(ContinuationRelativize_lock , PaddedMonitor, nosafepoint-3);
283 MUTEX_DEFN(CodeHeapStateAnalytics_lock , PaddedMutex , safepoint);
284 MUTEX_DEFN(ThreadsSMRDelete_lock , PaddedMonitor, service-2); // Holds ConcurrentHashTableResize_lock
285 MUTEX_DEFN(ThreadIdTableCreate_lock , PaddedMutex , safepoint);
286 MUTEX_DEFN(DCmdFactory_lock , PaddedMutex , nosafepoint);
287 MUTEX_DEFN(NMTQuery_lock , PaddedMutex , safepoint);
288 MUTEX_DEFN(NMTCompilationCostHistory_lock , PaddedMutex , nosafepoint);
289 MUTEX_DEFN(NmtVirtualMemory_lock , PaddedMutex , service-4); // Must be lower than G1Mapper_lock used from G1RegionsSmallerThanCommitSizeMapper::commit_regions
290 #if INCLUDE_CDS
291 #if INCLUDE_JVMTI
292 MUTEX_DEFN(CDSClassFileStream_lock , PaddedMutex , safepoint);
293 #endif
294 MUTEX_DEFN(DumpTimeTable_lock , PaddedMutex , nosafepoint);
295 MUTEX_DEFN(CDSLambda_lock , PaddedMutex , nosafepoint);
296 MUTEX_DEFN(DumpRegion_lock , PaddedMutex , nosafepoint);
297 MUTEX_DEFN(ClassListFile_lock , PaddedMutex , nosafepoint);
298 MUTEX_DEFN(UnregisteredClassesTable_lock , PaddedMutex , nosafepoint-1);
299 MUTEX_DEFN(LambdaFormInvokers_lock , PaddedMutex , safepoint);
300 MUTEX_DEFN(ScratchObjects_lock , PaddedMutex , nosafepoint-1); // Holds DumpTimeTable_lock
301 #endif // INCLUDE_CDS
302 MUTEX_DEFN(Bootclasspath_lock , PaddedMutex , nosafepoint);
303
304 #if INCLUDE_JVMCI
305 // JVMCIRuntime::_lock must be acquired before JVMCI_lock to avoid deadlock
306 MUTEX_DEFN(JVMCIRuntime_lock , PaddedMonitor, safepoint, true);
307 #endif
308
309 MUTEX_DEFN(ThreadsLockThrottle_lock , PaddedMonitor, safepoint);
310
311 // These locks have relative rankings, and inherit safepoint checking attributes from that rank.
312 MUTEX_DEFL(VtableStubs_lock , PaddedMutex , CompiledIC_lock); // Also holds DumpTimeTable_lock
313 MUTEX_DEFL(CodeCache_lock , PaddedMonitor, VtableStubs_lock);
314 MUTEX_DEFL(NMethodState_lock , PaddedMutex , CodeCache_lock);
315
316 // tty_lock is held when printing nmethod and its relocations which use this lock.
317 MUTEX_DEFL(ExternalsRecorder_lock , PaddedMutex , tty_lock);
318
319 MUTEX_DEFL(Threads_lock , PaddedMonitor, CompileThread_lock, true);
320 MUTEX_DEFL(Compile_lock , PaddedMutex , MethodCompileQueue_lock);
321 MUTEX_DEFL(Heap_lock , PaddedMonitor, AdapterHandlerLibrary_lock);
322
323 MUTEX_DEFL(PerfDataMemAlloc_lock , PaddedMutex , Heap_lock);
324 MUTEX_DEFL(PerfDataManager_lock , PaddedMutex , Heap_lock);
325 MUTEX_DEFL(VMOperation_lock , PaddedMonitor, Heap_lock, true);
326 MUTEX_DEFL(ClassInitError_lock , PaddedMonitor, Threads_lock);
327
328 if (UseG1GC) {
329 MUTEX_DEFL(G1OldGCCount_lock , PaddedMonitor, Threads_lock, true);
330 MUTEX_DEFL(G1RareEvent_lock , PaddedMutex , Threads_lock, true);
331 }
332
333 MUTEX_DEFL(CompileTaskAlloc_lock , PaddedMutex , MethodCompileQueue_lock);
334 #if INCLUDE_PARALLELGC
335 if (UseParallelGC) {
336 MUTEX_DEFL(PSOldGenExpand_lock , PaddedMutex , Heap_lock, true);
337 }
338 #endif
339 MUTEX_DEFL(Module_lock , PaddedMutex , ClassLoaderDataGraph_lock);
340 MUTEX_DEFL(SystemDictionary_lock , PaddedMonitor, Module_lock);
341 #if INCLUDE_JVMCI
342 // JVMCIRuntime_lock must be acquired before JVMCI_lock to avoid deadlock
343 MUTEX_DEFL(JVMCI_lock , PaddedMonitor, JVMCIRuntime_lock);
344 #endif
345 MUTEX_DEFL(JvmtiThreadState_lock , PaddedMutex , JvmtiVTMSTransition_lock); // Used by JvmtiThreadState/JvmtiEventController
346 MUTEX_DEFL(SharedDecoder_lock , PaddedMutex , NmtVirtualMemory_lock); // Must be lower than NmtVirtualMemory_lock due to MemTracker::print_containing_region
347
348 // Allocate RecursiveMutex
349 MultiArray_lock = new RecursiveMutex();
350 }
351
352 #undef MUTEX_DEFL
353 #undef MUTEX_DEFN
354 #undef MUTEX_DEF
355 #undef MUTEX_STORAGE
356 #undef MUTEX_STORAGE_NAME
357
358 void MutexLockerImpl::post_initialize() {
359 // Print mutex ranks if requested.
360 LogTarget(Info, vmmutex) lt;
361 if (lt.is_enabled()) {
362 ResourceMark rm;
363 LogStream ls(lt);
364 Mutex::print_lock_ranks(&ls);
365 }
366 }
367
368 GCMutexLocker::GCMutexLocker(Mutex* mutex) {
369 if (SafepointSynchronize::is_at_safepoint()) {
370 _locked = false;
371 } else {
372 _mutex = mutex;
373 _locked = true;
374 _mutex->lock();
375 }
376 }