1 /*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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24
25 #ifndef SHARE_RUNTIME_MUTEXLOCKER_HPP
26 #define SHARE_RUNTIME_MUTEXLOCKER_HPP
27
28 #include "logging/log.hpp"
29 #include "memory/allocation.hpp"
30 #include "runtime/flags/flagSetting.hpp"
31 #include "runtime/mutex.hpp"
32 #include "runtime/perfData.hpp"
33 #include "runtime/thread.hpp"
34
35 // Mutexes used in the VM.
36
37 extern Mutex* Patching_lock; // a lock used to guard code patching of compiled code
38 extern Mutex* NMethodState_lock; // a lock used to guard a compiled method state
39 extern Monitor* SystemDictionary_lock; // a lock on the system dictionary
40 extern Mutex* InvokeMethodTypeTable_lock;
41 extern Monitor* InvokeMethodIntrinsicTable_lock;
42 extern Mutex* SharedDictionary_lock; // a lock on the CDS shared dictionary
43 extern Monitor* ClassInitError_lock; // a lock on the class initialization error table
44 extern Mutex* Module_lock; // a lock on module and package related data structures
45 extern Mutex* CompiledIC_lock; // a lock used to guard compiled IC patching and access
46 extern Mutex* InlineCacheBuffer_lock; // a lock used to guard the InlineCacheBuffer
47 extern Mutex* VMStatistic_lock; // a lock used to guard statistics count increment
48 extern Mutex* JmethodIdCreation_lock; // a lock on creating JNI method identifiers
49 extern Mutex* JfieldIdCreation_lock; // a lock on creating JNI static field identifiers
50 extern Monitor* JNICritical_lock; // a lock used while entering and exiting JNI critical regions, allows GC to sometimes get in
51 extern Mutex* JvmtiThreadState_lock; // a lock on modification of JVMTI thread data
52 extern Monitor* EscapeBarrier_lock; // a lock to sync reallocating and relocking objects because of JVMTI access
53 extern Monitor* JvmtiVTMSTransition_lock; // a lock for Virtual Thread Mount State transition (VTMS transition) management
54 extern Monitor* Heap_lock; // a lock on the heap
55 #ifdef INCLUDE_PARALLELGC
56 extern Mutex* PSOldGenExpand_lock; // a lock on expanding the heap
57 #endif
58 extern Mutex* AdapterHandlerLibrary_lock; // a lock on the AdapterHandlerLibrary
59 extern Mutex* SignatureHandlerLibrary_lock; // a lock on the SignatureHandlerLibrary
60 extern Mutex* VtableStubs_lock; // a lock on the VtableStubs
61 extern Mutex* SymbolArena_lock; // a lock on the symbol table arena
62 extern Monitor* StringDedup_lock; // a lock on the string deduplication facility
63 extern Mutex* StringDedupIntern_lock; // a lock on StringTable notification of StringDedup
64 extern Monitor* CodeCache_lock; // a lock on the CodeCache
65 extern Mutex* TouchedMethodLog_lock; // a lock on allocation of LogExecutedMethods info
66 extern Mutex* RetData_lock; // a lock on installation of RetData inside method data
67 extern Monitor* VMOperation_lock; // a lock on queue of vm_operations waiting to execute
68 extern Monitor* Threads_lock; // a lock on the Threads table of active Java threads
69 // (also used by Safepoints too to block threads creation/destruction)
70 extern Mutex* NonJavaThreadsList_lock; // a lock on the NonJavaThreads list
71 extern Mutex* NonJavaThreadsListSync_lock; // a lock for NonJavaThreads list synchronization
72 extern Monitor* CGC_lock; // used for coordination between
73 // fore- & background GC threads.
74 extern Monitor* STS_lock; // used for joining/leaving SuspendibleThreadSet.
75 extern Monitor* G1OldGCCount_lock; // in support of "concurrent" full gc
76 extern Mutex* G1RareEvent_lock; // Synchronizes (rare) parallel GC operations.
77 extern Mutex* G1DetachedRefinementStats_lock; // Lock protecting detached refinement stats
78 extern Mutex* MarkStackFreeList_lock; // Protects access to the global mark stack free list.
79 extern Mutex* MarkStackChunkList_lock; // Protects access to the global mark stack chunk list.
80 extern Mutex* MonitoringSupport_lock; // Protects updates to the serviceability memory pools and allocated memory high water mark.
81 extern Monitor* ConcurrentGCBreakpoints_lock; // Protects concurrent GC breakpoint management
82 extern Mutex* Compile_lock; // a lock held when Compilation is updating code (used to block CodeCache traversal, CHA updates, etc)
83 extern Monitor* MethodCompileQueue_lock; // a lock held when method compilations are enqueued, dequeued
84 extern Monitor* MethodCompileQueueC1_lock; // a lock held when method compilations are enqueued, dequeued
85 extern Monitor* MethodCompileQueueC2_lock; // a lock held when method compilations are enqueued, dequeued
86 extern Monitor* MethodCompileQueueC3_lock; // a lock held when method compilations are enqueued, dequeued
87 extern Monitor* MethodCompileQueueSC1_lock; // a lock held when method compilations are enqueued, dequeued
88 extern Monitor* MethodCompileQueueSC2_lock; // a lock held when method compilations are enqueued, dequeued
89 extern Monitor* CompileThread_lock; // a lock held by compile threads during compilation system initialization
90 extern Monitor* Compilation_lock; // a lock used to pause compilation
91 extern Mutex* TrainingData_lock; // a lock used when accessing training records
92 extern Monitor* TrainingReplayQueue_lock; // a lock held when class are added/removed to the training replay queue
93 extern Mutex* CompileTaskAlloc_lock; // a lock held when CompileTasks are allocated
94 extern Mutex* CompileStatistics_lock; // a lock held when updating compilation statistics
95 extern Mutex* DirectivesStack_lock; // a lock held when mutating the dirstack and ref counting directives
96 extern Monitor* Terminator_lock; // a lock used to guard termination of the vm
97 extern Monitor* InitCompleted_lock; // a lock used to signal threads waiting on init completed
98 extern Monitor* BeforeExit_lock; // a lock used to guard cleanups and shutdown hooks
99 extern Monitor* Notify_lock; // a lock used to synchronize the start-up of the vm
100 extern Mutex* ExceptionCache_lock; // a lock used to synchronize exception cache updates
101
102 #ifndef PRODUCT
103 extern Mutex* FullGCALot_lock; // a lock to make FullGCALot MT safe
104 #endif // PRODUCT
105
106 extern Mutex* RawMonitor_lock;
107 extern Mutex* PerfDataMemAlloc_lock; // a lock on the allocator for PerfData memory for performance data
108 extern Mutex* PerfDataManager_lock; // a long on access to PerfDataManager resources
109
110 extern Mutex* FreeList_lock; // protects the free region list during safepoints
111 extern Mutex* OldSets_lock; // protects the old region sets
112 extern Mutex* Uncommit_lock; // protects the uncommit list when not at safepoints
113 extern Monitor* RootRegionScan_lock; // used to notify that the CM threads have finished scanning the IM snapshot regions
114
115 extern Mutex* Management_lock; // a lock used to serialize JVM management
116 extern Monitor* MonitorDeflation_lock; // a lock used for monitor deflation thread operation
117 extern Monitor* Service_lock; // a lock used for service thread operation
118 extern Monitor* Notification_lock; // a lock used for notification thread operation
119 extern Monitor* PeriodicTask_lock; // protects the periodic task structure
120 extern Monitor* RedefineClasses_lock; // locks classes from parallel redefinition
121 extern Mutex* Verify_lock; // synchronize initialization of verify library
122 extern Monitor* ThreadsSMRDelete_lock; // Used by ThreadsSMRSupport to take pressure off the Threads_lock
123 extern Mutex* ThreadIdTableCreate_lock; // Used by ThreadIdTable to lazily create the thread id table
124 extern Mutex* SharedDecoder_lock; // serializes access to the decoder during normal (not error reporting) use
125 extern Mutex* DCmdFactory_lock; // serialize access to DCmdFactory information
126 extern Mutex* NMTQuery_lock; // serialize NMT Dcmd queries
127 extern Mutex* NMTCompilationCostHistory_lock; // guards NMT compilation cost history
128 #if INCLUDE_CDS
129 #if INCLUDE_JVMTI
130 extern Mutex* CDSClassFileStream_lock; // FileMapInfo::open_stream_for_jvmti
131 #endif
132 extern Mutex* DumpTimeTable_lock; // SystemDictionaryShared::_dumptime_table
133 extern Mutex* CDSLambda_lock; // SystemDictionaryShared::get_shared_lambda_proxy_class
134 extern Mutex* DumpRegion_lock; // Symbol::operator new(size_t sz, int len)
135 extern Mutex* ClassListFile_lock; // ClassListWriter()
136 extern Mutex* UnregisteredClassesTable_lock; // UnregisteredClassesTableTable
137 extern Mutex* LambdaFormInvokers_lock; // Protecting LambdaFormInvokers::_lambdaform_lines
138 extern Mutex* ScratchObjects_lock; // Protecting _scratch_xxx_table in heapShared.cpp
139 extern Mutex* ArchivedObjectTables_lock; // Protecting the table used by HeapShared::get_archived_object_permanent_index()
140 #endif // INCLUDE_CDS
141 #if INCLUDE_JFR
142 extern Mutex* JfrStacktrace_lock; // used to guard access to the JFR stacktrace table
143 extern Monitor* JfrMsg_lock; // protects JFR messaging
144 extern Mutex* JfrBuffer_lock; // protects JFR buffer operations
145 extern Monitor* JfrThreadSampler_lock; // used to suspend/resume JFR thread sampler
146 #endif
147
148 extern Mutex* Metaspace_lock; // protects Metaspace virtualspace and chunk expansions
149 extern Monitor* MetaspaceCritical_lock; // synchronizes failed metaspace allocations that risk throwing metaspace OOM
150 extern Mutex* ClassLoaderDataGraph_lock; // protects CLDG list, needed for concurrent unloading
151
152
153 extern Mutex* CodeHeapStateAnalytics_lock; // lock print functions against concurrent analyze functions.
154 // Only used locally in PrintCodeCacheLayout processing.
155
156 extern Mutex* ExternalsRecorder_lock; // used to guard access to the external addresses table
157
158 extern Monitor* ContinuationRelativize_lock;
159
160 #if INCLUDE_JVMCI
161 extern Monitor* JVMCI_lock; // protects global JVMCI critical sections
162 extern Monitor* JVMCIRuntime_lock; // protects critical sections for a specific JVMCIRuntime object
163 #endif
164
165 extern Mutex* Bootclasspath_lock;
166
167 extern Mutex* tty_lock; // lock to synchronize output.
168
169 // A MutexLocker provides mutual exclusion with respect to a given mutex
170 // for the scope which contains the locker. The lock is an OS lock, not
171 // an object lock, and the two do not interoperate. Do not use Mutex-based
172 // locks to lock on Java objects, because they will not be respected if a
173 // that object is locked using the Java locking mechanism.
174 //
175 // NOTE WELL!!
176 //
177 // See orderAccess.hpp. We assume throughout the VM that MutexLocker's
178 // and friends constructors do a fence, a lock and an acquire *in that
179 // order*. And that their destructors do a release and unlock, in *that*
180 // order. If their implementations change such that these assumptions
181 // are violated, a whole lot of code will break.
182
183 // Print all mutexes/monitors that are currently owned by a thread; called
184 // by fatal error handler.
185 void print_owned_locks_on_error(outputStream* st);
186 void print_lock_ranks(outputStream* st);
187
188 // for debugging: check that we're already owning this lock (or are at a safepoint / handshake)
189 #ifdef ASSERT
190 void assert_locked_or_safepoint(const Mutex* lock);
191 void assert_lock_strong(const Mutex* lock);
192 #else
193 #define assert_locked_or_safepoint(lock)
194 #define assert_lock_strong(lock)
195 #endif
196
197 // Internal implementation. Skips on null Mutex.
198 // Subclasses enforce stronger invariants.
199 class MutexLockerImpl: public StackObj {
200 protected:
201 Mutex* _mutex;
202 bool _prof;
203 elapsedTimer _before;
204 elapsedTimer _after;
205
206 private:
207 static PerfCounter** _perf_lock_count;
208 static PerfCounter** _perf_lock_wait_time;
209 static PerfCounter** _perf_lock_hold_time;
210
211 public:
212
213 MutexLockerImpl(Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
214 _mutex(mutex), _prof(ProfileVMLocks && Thread::current_or_null() != nullptr && Thread::current()->profile_vm_locks()) {
215
216 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag;
217 if (_mutex != nullptr) {
218 if (_prof) { _before.start(); } // before
219
220 if (no_safepoint_check) {
221 _mutex->lock_without_safepoint_check();
222 } else {
223 _mutex->lock();
224 }
225
226 if (_prof) { _before.stop(); _after.start(); } // after
227 }
228 }
229
230 MutexLockerImpl(Thread* thread, Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
231 _mutex(mutex), _prof(thread->profile_vm_locks()) {
232
233 if (_prof) { _before.start(); } // before
234
235 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag;
236 if (_mutex != nullptr) {
237 if (no_safepoint_check) {
238 _mutex->lock_without_safepoint_check(thread);
239 } else {
240 _mutex->lock(thread);
241 }
242 }
243
244 if (_prof) { _before.stop(); _after.start(); } // after
245 }
246
247 ~MutexLockerImpl() {
248 if (_mutex != nullptr) {
249 assert_lock_strong(_mutex);
250 _mutex->unlock();
251
252 if (_mutex->id() == -1) {
253 log_trace(init)("Unnamed unclassified lock: %s", _mutex->name());
254 }
255
256 if (_prof) {
257 assert(UsePerfData, "required");
258 _after.stop();
259 _perf_lock_count [_mutex->id() + 1]->inc();
260 _perf_lock_wait_time[_mutex->id() + 1]->inc(_before.ticks());
261 _perf_lock_hold_time[_mutex->id() + 1]->inc(_after.ticks());
262 }
263 }
264 }
265
266 private:
267 static void print_counter_on(outputStream* st, const char* name, bool is_unique, int idx);
268
269 public:
270 static int name2id(const char* name);
271
272 static void post_initialize();
273 static void init_counters();
274 static void print_counters_on(outputStream* st);
275 };
276
277 // Simplest mutex locker.
278 // Does not allow null mutexes.
279 class MutexLocker: public MutexLockerImpl {
280 public:
281 MutexLocker(Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
282 MutexLockerImpl(mutex, flag) {
283 assert(mutex != nullptr, "null mutex not allowed");
284 }
285
286 MutexLocker(Thread* thread, Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
287 MutexLockerImpl(thread, mutex, flag) {
288 assert(mutex != nullptr, "null mutex not allowed");
289 }
290 };
291
292 // Conditional mutex locker.
293 // Like MutexLocker above, but only locks when condition is true.
294 class ConditionalMutexLocker: public MutexLockerImpl {
295 public:
296 ConditionalMutexLocker(Mutex* mutex, bool condition, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
297 MutexLockerImpl(condition ? mutex : nullptr, flag) {
298 assert(!condition || mutex != nullptr, "null mutex not allowed when locking");
299 }
300
301 ConditionalMutexLocker(Thread* thread, Mutex* mutex, bool condition, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
302 MutexLockerImpl(thread, condition ? mutex : nullptr, flag) {
303 assert(!condition || mutex != nullptr, "null mutex not allowed when locking");
304 }
305 };
306
307 // A MonitorLocker is like a MutexLocker above, except it allows
308 // wait/notify as well which are delegated to the underlying Monitor.
309 // It also disallows null.
310 class MonitorLocker: public MutexLockerImpl {
311 Mutex::SafepointCheckFlag _flag;
312
313 protected:
314 Monitor* as_monitor() const {
315 return static_cast<Monitor*>(_mutex);
316 }
317
318 public:
319 MonitorLocker(Monitor* monitor, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
320 MutexLockerImpl(monitor, flag), _flag(flag) {
321 // Superclass constructor did locking
322 assert(monitor != nullptr, "null monitor not allowed");
323 }
324
325 MonitorLocker(Thread* thread, Monitor* monitor, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
326 MutexLockerImpl(thread, monitor, flag), _flag(flag) {
327 // Superclass constructor did locking
328 assert(monitor != nullptr, "null monitor not allowed");
329 }
330
331 bool wait(int64_t timeout = 0) {
332 return _flag == Mutex::_safepoint_check_flag ?
333 as_monitor()->wait(timeout) : as_monitor()->wait_without_safepoint_check(timeout);
334 }
335
336 void notify_all() {
337 as_monitor()->notify_all();
338 }
339
340 void notify() {
341 as_monitor()->notify();
342 }
343 };
344
345
346 // A GCMutexLocker is usually initialized with a mutex that is
347 // automatically acquired in order to do GC. The function that
348 // synchronizes using a GCMutexLocker may be called both during and between
349 // GC's. Thus, it must acquire the mutex if GC is not in progress, but not
350 // if GC is in progress (since the mutex is already held on its behalf.)
351
352 class GCMutexLocker: public StackObj {
353 private:
354 Mutex* _mutex;
355 bool _locked;
356 public:
357 GCMutexLocker(Mutex* mutex);
358 ~GCMutexLocker() { if (_locked) _mutex->unlock(); }
359 };
360
361 // A MutexUnlocker temporarily exits a previously
362 // entered mutex for the scope which contains the unlocker.
363
364 class MutexUnlocker: StackObj {
365 private:
366 Mutex* _mutex;
367 bool _no_safepoint_check;
368
369 public:
370 MutexUnlocker(Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
371 _mutex(mutex),
372 _no_safepoint_check(flag == Mutex::_no_safepoint_check_flag) {
373 _mutex->unlock();
374 }
375
376 ~MutexUnlocker() {
377 if (_no_safepoint_check) {
378 _mutex->lock_without_safepoint_check();
379 } else {
380 _mutex->lock();
381 }
382 }
383 };
384
385 // Instance of a RecursiveLock that may be held through Java heap allocation, which may include calls to Java,
386 // and JNI event notification for resource exhaustion for metaspace or heap.
387 extern RecursiveMutex* MultiArray_lock;
388
389 // RAII locker for a RecursiveMutex. See comments in mutex.hpp for more information.
390 class RecursiveLocker {
391 RecursiveMutex* _lock;
392 Thread* _thread;
393 public:
394 RecursiveLocker(RecursiveMutex* lock, Thread* current) : _lock(lock), _thread(current) {
395 _lock->lock(_thread);
396 }
397 ~RecursiveLocker() {
398 _lock->unlock(_thread);
399 }
400 };
401
402 #endif // SHARE_RUNTIME_MUTEXLOCKER_HPP