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