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