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 "compiler/compiler_globals.hpp"
26 #include "gc/shared/gc_globals.hpp"
27 #include "logging/log.hpp"
28 #include "logging/logStream.hpp"
29 #include "memory/resourceArea.hpp"
30 #include "memory/universe.hpp"
31 #include "runtime/java.hpp"
32 #include "runtime/javaThread.hpp"
33 #include "runtime/mutexLocker.hpp"
34 #include "runtime/safepoint.hpp"
35 #include "runtime/vmThread.hpp"
36 #include "services/management.hpp"
37 #include "utilities/vmError.hpp"
38
39 // Mutexes used in the VM (see comment in mutexLocker.hpp):
40
41 Mutex* NMethodState_lock = nullptr;
42 Monitor* SystemDictionary_lock = nullptr;
43 Mutex* InvokeMethodTypeTable_lock = nullptr;
44 Monitor* InvokeMethodIntrinsicTable_lock = nullptr;
45 Mutex* SharedDictionary_lock = nullptr;
46 Monitor* ClassInitError_lock = nullptr;
47 Mutex* Module_lock = nullptr;
48 Mutex* CompiledIC_lock = nullptr;
49 Mutex* VMStatistic_lock = nullptr;
50 Mutex* JmethodIdCreation_lock = nullptr;
51 Mutex* JfieldIdCreation_lock = nullptr;
52 Monitor* JNICritical_lock = nullptr;
53 Mutex* JvmtiThreadState_lock = nullptr;
54 Monitor* EscapeBarrier_lock = nullptr;
55 Monitor* JvmtiVTMSTransition_lock = nullptr;
56 Mutex* JvmtiVThreadSuspend_lock = nullptr;
57 Monitor* Heap_lock = nullptr;
58 #if INCLUDE_PARALLELGC
59 Mutex* PSOldGenExpand_lock = nullptr;
60 #endif
61 Mutex* AdapterHandlerLibrary_lock = nullptr;
62 Mutex* SignatureHandlerLibrary_lock = nullptr;
63 Mutex* VtableStubs_lock = nullptr;
64 Mutex* SymbolArena_lock = nullptr;
65 Monitor* StringDedup_lock = nullptr;
66 Mutex* StringDedupIntern_lock = nullptr;
67 Monitor* CodeCache_lock = nullptr;
68 Mutex* TouchedMethodLog_lock = nullptr;
69 Mutex* RetData_lock = nullptr;
70 Monitor* VMOperation_lock = nullptr;
71 Monitor* ThreadsLockThrottle_lock = nullptr;
72 Monitor* Threads_lock = nullptr;
73 Mutex* NonJavaThreadsList_lock = nullptr;
74 Mutex* NonJavaThreadsListSync_lock = nullptr;
75 Monitor* CGC_lock = nullptr;
76 Monitor* STS_lock = nullptr;
77 Monitor* G1OldGCCount_lock = nullptr;
78 Mutex* G1RareEvent_lock = nullptr;
79 Mutex* G1DetachedRefinementStats_lock = nullptr;
80 Mutex* MarkStackFreeList_lock = nullptr;
81 Mutex* MarkStackChunkList_lock = nullptr;
82 Mutex* MonitoringSupport_lock = nullptr;
83 Monitor* ConcurrentGCBreakpoints_lock = nullptr;
84 Mutex* Compile_lock = nullptr;
85 Monitor* MethodCompileQueue_lock = nullptr;
86 Monitor* MethodCompileQueueC1_lock = nullptr;
87 Monitor* MethodCompileQueueC2_lock = nullptr;
88 Monitor* MethodCompileQueueC3_lock = nullptr;
89 Monitor* MethodCompileQueueSC1_lock = nullptr;
90 Monitor* MethodCompileQueueSC2_lock = nullptr;
91 Monitor* CompileThread_lock = nullptr;
92 Monitor* Compilation_lock = nullptr;
93 Monitor* CompileTaskAlloc_lock = nullptr;
94 Mutex* CompileStatistics_lock = nullptr;
95 Mutex* DirectivesStack_lock = nullptr;
96 Monitor* Terminator_lock = nullptr;
97 Monitor* InitCompleted_lock = nullptr;
98 Monitor* BeforeExit_lock = nullptr;
99 Monitor* Notify_lock = nullptr;
100 Mutex* ExceptionCache_lock = nullptr;
101 Mutex* TrainingData_lock = nullptr;
102 Monitor* TrainingReplayQueue_lock = nullptr;
103 #ifndef PRODUCT
104 Mutex* FullGCALot_lock = nullptr;
105 #endif
106
107 Mutex* tty_lock = nullptr;
108
109 Mutex* RawMonitor_lock = nullptr;
110 Mutex* PerfDataMemAlloc_lock = nullptr;
111 Mutex* PerfDataManager_lock = nullptr;
112
113 Mutex* FreeList_lock = nullptr;
114 Mutex* OldSets_lock = nullptr;
115 Mutex* Uncommit_lock = nullptr;
116 Monitor* RootRegionScan_lock = nullptr;
117
118 Mutex* Management_lock = nullptr;
119 Monitor* MonitorDeflation_lock = nullptr;
120 Monitor* Service_lock = nullptr;
121 Monitor* Notification_lock = nullptr;
122 Monitor* PeriodicTask_lock = nullptr;
123 Monitor* RedefineClasses_lock = nullptr;
124 Mutex* Verify_lock = nullptr;
125
126 #if INCLUDE_JFR
127 Mutex* JfrStacktrace_lock = nullptr;
128 Monitor* JfrMsg_lock = nullptr;
129 Mutex* JfrBuffer_lock = nullptr;
130 #endif
131
132 Mutex* CodeHeapStateAnalytics_lock = nullptr;
133
134 Mutex* ExternalsRecorder_lock = nullptr;
135
136 Mutex* AOTCodeCStrings_lock = nullptr;
137
138 Monitor* ContinuationRelativize_lock = nullptr;
139
140 Mutex* Metaspace_lock = nullptr;
141 Monitor* MetaspaceCritical_lock = nullptr;
142 Mutex* ClassLoaderDataGraph_lock = nullptr;
143 Monitor* ThreadsSMRDelete_lock = nullptr;
144 Mutex* ThreadIdTableCreate_lock = nullptr;
145 Mutex* SharedDecoder_lock = nullptr;
146 Mutex* DCmdFactory_lock = nullptr;
147 Mutex* NMTQuery_lock = nullptr;
148 Mutex* NMTCompilationCostHistory_lock = nullptr;
149 Mutex* NmtVirtualMemory_lock = nullptr;
150
151 #if INCLUDE_CDS
152 #if INCLUDE_JVMTI
153 Mutex* CDSClassFileStream_lock = nullptr;
154 #endif
155 Mutex* DumpTimeTable_lock = nullptr;
156 Mutex* CDSLambda_lock = nullptr;
157 Mutex* DumpRegion_lock = nullptr;
158 Mutex* ClassListFile_lock = nullptr;
159 Mutex* UnregisteredClassesTable_lock= nullptr;
160 Mutex* LambdaFormInvokers_lock = nullptr;
161 Mutex* ScratchObjects_lock = nullptr;
162 Mutex* ArchivedObjectTables_lock = nullptr;
163 Mutex* FinalImageRecipes_lock = nullptr;
164 #endif // INCLUDE_CDS
165 Mutex* Bootclasspath_lock = nullptr;
166
167 #if INCLUDE_JVMCI
168 Monitor* JVMCI_lock = nullptr;
169 Monitor* JVMCIRuntime_lock = nullptr;
170 #endif
171
172 // Only one RecursiveMutex
173 RecursiveMutex* MultiArray_lock = nullptr;
174
175 #ifdef ASSERT
176 void assert_locked_or_safepoint(const Mutex* lock) {
177 if (DebuggingContext::is_enabled() || VMError::is_error_reported()) return;
178 // check if this thread owns the lock (common case)
179 assert(lock != nullptr, "Need non-null lock");
180 if (lock->owned_by_self()) return;
181 if (SafepointSynchronize::is_at_safepoint()) return;
182 if (!Universe::is_fully_initialized()) return;
183 fatal("must own lock %s", lock->name());
184 }
185
186 // a stronger assertion than the above
187 void assert_lock_strong(const Mutex* lock) {
188 if (DebuggingContext::is_enabled() || VMError::is_error_reported()) return;
189 assert(lock != nullptr, "Need non-null lock");
190 if (lock->owned_by_self()) return;
191 fatal("must own lock %s", lock->name());
192 }
193 #endif
194
195 #define MUTEX_STORAGE_NAME(name) name##_storage
196 #define MUTEX_STORAGE(name, type) alignas(type) static uint8_t MUTEX_STORAGE_NAME(name)[sizeof(type)]
197 #define MUTEX_DEF(name, type, pri, ...) { \
198 assert(name == nullptr, "Mutex/Monitor initialized twice"); \
199 MUTEX_STORAGE(name, type); \
200 name = ::new(static_cast<void*>(MUTEX_STORAGE_NAME(name))) type((pri), #name, ##__VA_ARGS__); \
201 Mutex::add_mutex(name); \
202 }
203 #define MUTEX_DEFN(name, type, pri, ...) MUTEX_DEF(name, type, Mutex::pri, ##__VA_ARGS__)
204
205 // Specify relative ranked lock
206 #ifdef ASSERT
207 #define MUTEX_DEFL(name, type, held_lock, ...) MUTEX_DEF(name, type, (held_lock)->rank() - 1, ##__VA_ARGS__)
208 #else
209 #define MUTEX_DEFL(name, type, held_lock, ...) MUTEX_DEFN(name, type, safepoint, ##__VA_ARGS__)
210 #endif
211
212 // Using Padded subclasses to prevent false sharing of these global monitors and mutexes.
213 void mutex_init() {
214 MUTEX_DEFN(tty_lock , PaddedMutex , tty); // allow to lock in VM
215
216 MUTEX_DEFN(STS_lock , PaddedMonitor, nosafepoint);
217
218 if (UseG1GC) {
219 MUTEX_DEFN(CGC_lock , PaddedMonitor, nosafepoint);
220
221 MUTEX_DEFN(G1DetachedRefinementStats_lock, PaddedMutex , nosafepoint-2);
222
223 MUTEX_DEFN(FreeList_lock , PaddedMutex , service-1);
224 MUTEX_DEFN(OldSets_lock , PaddedMutex , nosafepoint);
225 MUTEX_DEFN(Uncommit_lock , PaddedMutex , service-2);
226 MUTEX_DEFN(RootRegionScan_lock , PaddedMonitor, nosafepoint-1);
227
228 MUTEX_DEFN(MarkStackFreeList_lock , PaddedMutex , nosafepoint);
229 MUTEX_DEFN(MarkStackChunkList_lock , PaddedMutex , nosafepoint);
230 }
231 MUTEX_DEFN(MonitoringSupport_lock , PaddedMutex , service-1); // used for serviceability monitoring support
232
233 MUTEX_DEFN(StringDedup_lock , PaddedMonitor, nosafepoint);
234 MUTEX_DEFN(StringDedupIntern_lock , PaddedMutex , nosafepoint);
235 MUTEX_DEFN(RawMonitor_lock , PaddedMutex , nosafepoint-1);
236
237 MUTEX_DEFN(Metaspace_lock , PaddedMutex , nosafepoint-3);
238 MUTEX_DEFN(MetaspaceCritical_lock , PaddedMonitor, nosafepoint-1);
239
240 MUTEX_DEFN(MonitorDeflation_lock , PaddedMonitor, nosafepoint); // used for monitor deflation thread operations
241 MUTEX_DEFN(Service_lock , PaddedMonitor, service); // used for service thread operations
242 MUTEX_DEFN(Notification_lock , PaddedMonitor, service); // used for notification thread operations
243
244 MUTEX_DEFN(JmethodIdCreation_lock , PaddedMutex , nosafepoint-2); // used for creating jmethodIDs.
245 MUTEX_DEFN(InvokeMethodTypeTable_lock , PaddedMutex , safepoint);
246 MUTEX_DEFN(InvokeMethodIntrinsicTable_lock , PaddedMonitor, safepoint);
247 MUTEX_DEFN(AdapterHandlerLibrary_lock , PaddedMutex , safepoint);
248 MUTEX_DEFN(SharedDictionary_lock , PaddedMutex , safepoint);
249 MUTEX_DEFN(VMStatistic_lock , PaddedMutex , safepoint);
250 MUTEX_DEFN(SignatureHandlerLibrary_lock , PaddedMutex , safepoint);
251 MUTEX_DEFN(SymbolArena_lock , PaddedMutex , nosafepoint);
252 MUTEX_DEFN(ExceptionCache_lock , PaddedMutex , safepoint);
253 #ifndef PRODUCT
254 MUTEX_DEFN(FullGCALot_lock , PaddedMutex , safepoint); // a lock to make FullGCALot MT safe
255 #endif
256 MUTEX_DEFN(BeforeExit_lock , PaddedMonitor, safepoint);
257
258 MUTEX_DEFN(NonJavaThreadsList_lock , PaddedMutex , nosafepoint-1);
259 MUTEX_DEFN(NonJavaThreadsListSync_lock , PaddedMutex , nosafepoint);
260
261 MUTEX_DEFN(RetData_lock , PaddedMutex , safepoint);
262 MUTEX_DEFN(Terminator_lock , PaddedMonitor, safepoint, true);
263 MUTEX_DEFN(InitCompleted_lock , PaddedMonitor, nosafepoint);
264 MUTEX_DEFN(Notify_lock , PaddedMonitor, safepoint, true);
265
266 MUTEX_DEFN(JfieldIdCreation_lock , PaddedMutex , safepoint);
267
268 MUTEX_DEFN(CompiledIC_lock , PaddedMutex , nosafepoint); // locks VtableStubs_lock
269 MUTEX_DEFN(MethodCompileQueue_lock , PaddedMonitor, safepoint);
270 if (UseGlobalCompileQueueLock) {
271 MethodCompileQueueC1_lock = MethodCompileQueue_lock;
272 MethodCompileQueueC2_lock = MethodCompileQueue_lock;
273 MethodCompileQueueC3_lock = MethodCompileQueue_lock;
274 MethodCompileQueueSC1_lock = MethodCompileQueue_lock;
275 MethodCompileQueueSC2_lock = MethodCompileQueue_lock;
276 } else {
277 MUTEX_DEFN(MethodCompileQueueC1_lock , PaddedMonitor, safepoint);
278 MUTEX_DEFN(MethodCompileQueueC2_lock , PaddedMonitor, safepoint);
279 MUTEX_DEFN(MethodCompileQueueC3_lock , PaddedMonitor, safepoint);
280 MUTEX_DEFN(MethodCompileQueueSC1_lock , PaddedMonitor, safepoint);
281 MUTEX_DEFN(MethodCompileQueueSC2_lock , PaddedMonitor, safepoint);
282 }
283 MUTEX_DEFL(TrainingData_lock , PaddedMutex , MethodCompileQueue_lock);
284 MUTEX_DEFN(TrainingReplayQueue_lock , PaddedMonitor, safepoint);
285 MUTEX_DEFN(CompileStatistics_lock , PaddedMutex , safepoint);
286 MUTEX_DEFN(DirectivesStack_lock , PaddedMutex , nosafepoint);
287
288 MUTEX_DEFN(JvmtiVTMSTransition_lock , PaddedMonitor, safepoint); // used for Virtual Thread Mount State transition management
289 MUTEX_DEFN(JvmtiVThreadSuspend_lock , PaddedMutex, nosafepoint-1);
290 MUTEX_DEFN(EscapeBarrier_lock , PaddedMonitor, nosafepoint); // Used to synchronize object reallocation/relocking triggered by JVMTI
291 MUTEX_DEFN(Management_lock , PaddedMutex , safepoint); // used for JVM management
292
293 MUTEX_DEFN(ConcurrentGCBreakpoints_lock , PaddedMonitor, safepoint, true);
294 MUTEX_DEFN(TouchedMethodLog_lock , PaddedMutex , safepoint);
295
296 MUTEX_DEFN(CompileThread_lock , PaddedMonitor, safepoint);
297 MUTEX_DEFN(PeriodicTask_lock , PaddedMonitor, safepoint, true);
298 MUTEX_DEFN(RedefineClasses_lock , PaddedMonitor, safepoint);
299 MUTEX_DEFN(Verify_lock , PaddedMutex , safepoint);
300 MUTEX_DEFN(ClassLoaderDataGraph_lock , PaddedMutex , safepoint);
301
302 MUTEX_DEFN(Compilation_lock , PaddedMonitor, nosafepoint);
303
304 #if INCLUDE_JFR
305 MUTEX_DEFN(JfrBuffer_lock , PaddedMutex , event);
306 MUTEX_DEFN(JfrMsg_lock , PaddedMonitor, event);
307 MUTEX_DEFN(JfrStacktrace_lock , PaddedMutex , event);
308 #endif
309
310 MUTEX_DEFN(ContinuationRelativize_lock , PaddedMonitor, nosafepoint-3);
311 MUTEX_DEFN(CodeHeapStateAnalytics_lock , PaddedMutex , safepoint);
312 MUTEX_DEFN(ThreadsSMRDelete_lock , PaddedMonitor, service-2); // Holds ConcurrentHashTableResize_lock
313 MUTEX_DEFN(ThreadIdTableCreate_lock , PaddedMutex , safepoint);
314 MUTEX_DEFN(DCmdFactory_lock , PaddedMutex , nosafepoint);
315 MUTEX_DEFN(NMTQuery_lock , PaddedMutex , safepoint);
316 MUTEX_DEFN(NMTCompilationCostHistory_lock , PaddedMutex , nosafepoint);
317 MUTEX_DEFN(NmtVirtualMemory_lock , PaddedMutex , service-4); // Must be lower than G1Mapper_lock used from G1RegionsSmallerThanCommitSizeMapper::commit_regions
318 #if INCLUDE_CDS
319 #if INCLUDE_JVMTI
320 MUTEX_DEFN(CDSClassFileStream_lock , PaddedMutex , safepoint);
321 #endif
322 MUTEX_DEFN(DumpTimeTable_lock , PaddedMutex , nosafepoint);
323 MUTEX_DEFN(CDSLambda_lock , PaddedMutex , nosafepoint);
324 MUTEX_DEFN(DumpRegion_lock , PaddedMutex , nosafepoint);
325 MUTEX_DEFN(ClassListFile_lock , PaddedMutex , nosafepoint);
326 MUTEX_DEFN(UnregisteredClassesTable_lock , PaddedMutex , nosafepoint-1);
327 MUTEX_DEFN(LambdaFormInvokers_lock , PaddedMutex , safepoint);
328 MUTEX_DEFN(ScratchObjects_lock , PaddedMutex , nosafepoint-1); // Holds DumpTimeTable_lock
329 MUTEX_DEFN(ArchivedObjectTables_lock , PaddedMutex , nosafepoint);
330 MUTEX_DEFN(FinalImageRecipes_lock , PaddedMutex , nosafepoint);
331 #endif // INCLUDE_CDS
332 MUTEX_DEFN(Bootclasspath_lock , PaddedMutex , nosafepoint);
333
334 #if INCLUDE_JVMCI
335 // JVMCIRuntime::_lock must be acquired before JVMCI_lock to avoid deadlock
336 MUTEX_DEFN(JVMCIRuntime_lock , PaddedMonitor, safepoint, true);
337 #endif
338
339 MUTEX_DEFN(ThreadsLockThrottle_lock , PaddedMonitor, safepoint);
340
341 // These locks have relative rankings, and inherit safepoint checking attributes from that rank.
342 MUTEX_DEFL(VtableStubs_lock , PaddedMutex , CompiledIC_lock); // Also holds DumpTimeTable_lock
343 MUTEX_DEFL(CodeCache_lock , PaddedMonitor, VtableStubs_lock);
344 MUTEX_DEFL(NMethodState_lock , PaddedMutex , CodeCache_lock);
345
346 // tty_lock is held when printing nmethod and its relocations which use this lock.
347 MUTEX_DEFL(ExternalsRecorder_lock , PaddedMutex , tty_lock);
348
349 MUTEX_DEFL(AOTCodeCStrings_lock , PaddedMutex , tty_lock);
350
351 MUTEX_DEFL(Threads_lock , PaddedMonitor, CompileThread_lock, true);
352 MUTEX_DEFL(Compile_lock , PaddedMutex , MethodCompileQueue_lock);
353 MUTEX_DEFL(JNICritical_lock , PaddedMonitor, AdapterHandlerLibrary_lock); // used for JNI critical regions
354 MUTEX_DEFL(Heap_lock , PaddedMonitor, TrainingData_lock /*JNICritical_lock*/);
355
356 MUTEX_DEFL(PerfDataMemAlloc_lock , PaddedMutex , Heap_lock);
357 MUTEX_DEFL(PerfDataManager_lock , PaddedMutex , Heap_lock);
358 MUTEX_DEFL(VMOperation_lock , PaddedMonitor, Heap_lock, true);
359 MUTEX_DEFL(ClassInitError_lock , PaddedMonitor, Threads_lock);
360
361 if (UseG1GC) {
362 MUTEX_DEFL(G1OldGCCount_lock , PaddedMonitor, Threads_lock, true);
363 MUTEX_DEFL(G1RareEvent_lock , PaddedMutex , Threads_lock, true);
364 }
365
366 MUTEX_DEFL(CompileTaskAlloc_lock , PaddedMonitor, MethodCompileQueue_lock);
367 #if INCLUDE_PARALLELGC
368 if (UseParallelGC) {
369 MUTEX_DEFL(PSOldGenExpand_lock , PaddedMutex , Heap_lock, true);
370 }
371 #endif
372 MUTEX_DEFL(Module_lock , PaddedMutex , ClassLoaderDataGraph_lock);
373 MUTEX_DEFL(SystemDictionary_lock , PaddedMonitor, Module_lock);
374 #if INCLUDE_JVMCI
375 // JVMCIRuntime_lock must be acquired before JVMCI_lock to avoid deadlock
376 MUTEX_DEFL(JVMCI_lock , PaddedMonitor, JVMCIRuntime_lock);
377 #endif
378 MUTEX_DEFL(JvmtiThreadState_lock , PaddedMutex , JvmtiVTMSTransition_lock); // Used by JvmtiThreadState/JvmtiEventController
379 MUTEX_DEFL(SharedDecoder_lock , PaddedMutex , NmtVirtualMemory_lock); // Must be lower than NmtVirtualMemory_lock due to MemTracker::print_containing_region
380
381 // Allocate RecursiveMutex
382 MultiArray_lock = new RecursiveMutex();
383 }
384
385 #undef MUTEX_DEFL
386 #undef MUTEX_DEFN
387 #undef MUTEX_DEF
388 #undef MUTEX_STORAGE
389 #undef MUTEX_STORAGE_NAME
390
391 static const int MAX_NAMES = 200;
392 static const char* _names[MAX_NAMES] = { nullptr };
393 static bool _is_unique[MAX_NAMES] = { false };
394 static int _num_names = 0;
395
396 PerfCounter** MutexLockerImpl::_perf_lock_count = nullptr;
397 PerfCounter** MutexLockerImpl::_perf_lock_wait_time = nullptr;
398 PerfCounter** MutexLockerImpl::_perf_lock_hold_time = nullptr;
399
400 MutexLockerImpl::MutexLockerImpl(Mutex* mutex, Mutex::SafepointCheckFlag flag) :
401 _mutex(mutex),
402 _prof(ProfileVMLocks && Thread::current_or_null() != nullptr && Thread::current()->profile_vm_locks()) {
403
404 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag;
405 if (_mutex != nullptr) {
406 if (_prof) { _before.start(); } // before
407
408 if (no_safepoint_check) {
409 _mutex->lock_without_safepoint_check();
410 } else {
411 _mutex->lock();
412 }
413
414 if (_prof) { _before.stop(); _after.start(); } // after
415 }
416 }
417
418 MutexLockerImpl::MutexLockerImpl(Thread* thread, Mutex* mutex, Mutex::SafepointCheckFlag flag) :
419 _mutex(mutex), _prof(thread->profile_vm_locks()) {
420
421 if (_prof) { _before.start(); } // before
422
423 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag;
424 if (_mutex != nullptr) {
425 if (no_safepoint_check) {
426 _mutex->lock_without_safepoint_check(thread);
427 } else {
428 _mutex->lock(thread);
429 }
430 }
431
432 if (_prof) { _before.stop(); _after.start(); } // after
433 }
434
435 void MutexLockerImpl::init_counters() {
436 if (ProfileVMLocks && UsePerfData) {
437 ResourceMark rm;
438 EXCEPTION_MARK;
439 _perf_lock_count = NEW_C_HEAP_ARRAY(PerfCounter*, MAX_NAMES + 1, mtInternal);
440 _perf_lock_wait_time = NEW_C_HEAP_ARRAY(PerfCounter*, MAX_NAMES + 1, mtInternal);
441 _perf_lock_hold_time = NEW_C_HEAP_ARRAY(PerfCounter*, MAX_NAMES + 1, mtInternal);
442
443 NEWPERFEVENTCOUNTER(_perf_lock_count[0], SUN_RT, PerfDataManager::counter_name("Other", "Count"));
444 NEWPERFEVENTCOUNTER(_perf_lock_wait_time[0], SUN_RT, PerfDataManager::counter_name("Other", "BeforeTime"));
445 NEWPERFEVENTCOUNTER(_perf_lock_hold_time[0], SUN_RT, PerfDataManager::counter_name("Other", "AfterTime"));
446 for (int i = 0; i < MAX_NAMES; i++) {
447 ResourceMark rm;
448 const char* counter_name = _names[i];
449 if (counter_name == nullptr) {
450 stringStream ss;
451 ss.print("UnnamedMutex#%d", i);
452 counter_name = ss.as_string();
453 }
454 NEWPERFEVENTCOUNTER(_perf_lock_count[i + 1], SUN_RT, PerfDataManager::counter_name(counter_name, "Count"));
455 NEWPERFEVENTCOUNTER(_perf_lock_wait_time[i + 1], SUN_RT, PerfDataManager::counter_name(counter_name, "BeforeTime"));
456 NEWPERFEVENTCOUNTER(_perf_lock_hold_time[i + 1], SUN_RT, PerfDataManager::counter_name(counter_name, "AfterTime"));
457 }
458 if (HAS_PENDING_EXCEPTION) {
459 vm_exit_during_initialization("MutexLockerImpl::init_counters() failed unexpectedly");
460 }
461 }
462 }
463
464 int MutexLockerImpl::name2id(const char* name) {
465 if (ProfileVMLocks && UsePerfData) {
466 for (int i = 0; i < _num_names; i++) {
467 if (strcmp(_names[i], name) == 0) {
468 _is_unique[i] = false;
469 return i;
470 }
471 }
472 if (_num_names < MAX_NAMES) {
473 int new_id = _num_names++;
474 _names[new_id] = os::strdup(name, mtInternal);
475 _is_unique[new_id] = true;
476 return new_id;
477 }
478 log_debug(init)("Unnamed: %s", name); // no slots left
479 }
480 return -1;
481 }
482
483 void MutexLockerImpl::print_counter_on(outputStream* st, const char* name, bool is_unique, int idx) {
484 jlong count = _perf_lock_count[idx]->get_value();
485 if (count > 0) {
486 st->print_cr(" %3d: %s%40s = " JLONG_FORMAT_W(5) "us (" JLONG_FORMAT_W(5) "us) / " JLONG_FORMAT_W(9) " events",
487 idx, (is_unique ? " " : "M"), name,
488 Management::ticks_to_us(_perf_lock_hold_time[idx]->get_value()),
489 Management::ticks_to_us(_perf_lock_wait_time[idx]->get_value()),
490 count);
491 }
492 }
493
494 static jlong accumulate_lock_counters(PerfCounter** lock_counters) {
495 jlong acc = 0;
496 for (int i = 0; i < _num_names + 1; i++) { // 0 slot is reserved for unnamed locks
497 if (lock_counters[i] == nullptr) {
498 break;
499 }
500 acc += lock_counters[i]->get_value();
501 }
502 return acc;
503 }
504
505 void MutexLockerImpl::print_counters_on(outputStream* st) {
506 if (ProfileVMLocks && UsePerfData) {
507 jlong total_count = accumulate_lock_counters(_perf_lock_count);
508 jlong total_wait_time = accumulate_lock_counters(_perf_lock_wait_time);
509 jlong total_hold_time = accumulate_lock_counters(_perf_lock_hold_time);
510
511 st->print_cr("MutexLocker: Total: %d named locks (%d unique names); hold = " JLONG_FORMAT "us (wait = " JLONG_FORMAT "us) / " JLONG_FORMAT " events for thread \"main\"",
512 Mutex::num_mutex(), _num_names,
513 Management::ticks_to_us(total_hold_time),
514 Management::ticks_to_us(total_wait_time),
515 total_count);
516 for (int i = 0; i < _num_names; i++) {
517 print_counter_on(st, _names[i], _is_unique[i], i+1);
518 }
519 print_counter_on(st, "Unnamed / Other", false /*is_unique*/, 0);
520 } else {
521 st->print_cr("MutexLocker: no info (%s is disabled)", (UsePerfData ? "ProfileVMLocks" : "UsePerfData"));
522 }
523 }
524
525 void MutexLockerImpl::post_initialize() {
526 // Print mutex ranks if requested.
527 LogTarget(Info, vmmutex) lt;
528 if (lt.is_enabled()) {
529 ResourceMark rm;
530 LogStream ls(lt);
531 Mutex::print_lock_ranks(&ls);
532 }
533 }
534
535 GCMutexLocker::GCMutexLocker(Mutex* mutex) {
536 if (SafepointSynchronize::is_at_safepoint()) {
537 _locked = false;
538 } else {
539 _mutex = mutex;
540 _locked = true;
541 _mutex->lock();
542 }
543 }