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 Monitor* CompileTaskAlloc_lock; // a lock held when CompileTasks are allocated
96 extern Mutex* CompileStatistics_lock; // a lock held when updating compilation statistics
97 extern Mutex* DirectivesStack_lock; // a lock held when mutating the dirstack and ref counting directives
98 extern Monitor* Terminator_lock; // a lock used to guard termination of the vm
99 extern Monitor* InitCompleted_lock; // a lock used to signal threads waiting on init completed
100 extern Monitor* BeforeExit_lock; // a lock used to guard cleanups and shutdown hooks
101 extern Monitor* Notify_lock; // a lock used to synchronize the start-up of the vm
102 extern Mutex* ExceptionCache_lock; // a lock used to synchronize exception cache updates
103
104 #ifndef PRODUCT
105 extern Mutex* FullGCALot_lock; // a lock to make FullGCALot MT safe
106 #endif // PRODUCT
107
108 extern Mutex* RawMonitor_lock;
109 extern Mutex* PerfDataMemAlloc_lock; // a lock on the allocator for PerfData memory for performance data
110 extern Mutex* PerfDataManager_lock; // a long on access to PerfDataManager resources
111
112 extern Mutex* FreeList_lock; // protects the free region list during safepoints
113 extern Mutex* OldSets_lock; // protects the old region sets
114 extern Mutex* Uncommit_lock; // protects the uncommit list when not at safepoints
115 extern Monitor* RootRegionScan_lock; // used to notify that the CM threads have finished scanning the IM snapshot regions
116
117 extern Mutex* Management_lock; // a lock used to serialize JVM management
118 extern Monitor* MonitorDeflation_lock; // a lock used for monitor deflation thread operation
119 extern Monitor* Service_lock; // a lock used for service thread operation
120 extern Monitor* Notification_lock; // a lock used for notification thread operation
121 extern Monitor* PeriodicTask_lock; // protects the periodic task structure
122 extern Monitor* RedefineClasses_lock; // locks classes from parallel redefinition
123 extern Mutex* Verify_lock; // synchronize initialization of verify library
124 extern Monitor* ThreadsSMRDelete_lock; // Used by ThreadsSMRSupport to take pressure off the Threads_lock
125 extern Mutex* ThreadIdTableCreate_lock; // Used by ThreadIdTable to lazily create the thread id table
126 extern Mutex* SharedDecoder_lock; // serializes access to the decoder during normal (not error reporting) use
127 extern Mutex* DCmdFactory_lock; // serialize access to DCmdFactory information
128 extern Mutex* NMTQuery_lock; // serialize NMT Dcmd queries
129 extern Mutex* NMTCompilationCostHistory_lock; // guards NMT compilation cost history
130 extern Mutex* NmtVirtualMemory_lock; // guards NMT virtual memory updates
131 #if INCLUDE_CDS
132 #if INCLUDE_JVMTI
133 extern Mutex* CDSClassFileStream_lock; // FileMapInfo::open_stream_for_jvmti
134 #endif
135 extern Mutex* DumpTimeTable_lock; // SystemDictionaryShared::_dumptime_table
136 extern Mutex* CDSLambda_lock; // LambdaProxyClassDictionary::find_lambda_proxy_class
137 extern Mutex* DumpRegion_lock; // Symbol::operator new(size_t sz, int len)
138 extern Mutex* ClassListFile_lock; // ClassListWriter()
139 extern Mutex* UnregisteredClassesTable_lock; // UnregisteredClassesTableTable
140 extern Mutex* LambdaFormInvokers_lock; // Protecting LambdaFormInvokers::_lambdaform_lines
141 extern Mutex* ScratchObjects_lock; // Protecting _scratch_xxx_table in heapShared.cpp
142 extern Mutex* ArchivedObjectTables_lock; // Protecting the table used by HeapShared::get_archived_object_permanent_index()
143 extern Mutex* FinalImageRecipes_lock; // Protecting the tables used by FinalImageRecipes.
144 #endif // INCLUDE_CDS
145 #if INCLUDE_JFR
146 extern Mutex* JfrStacktrace_lock; // used to guard access to the JFR stacktrace table
147 extern Monitor* JfrMsg_lock; // protects JFR messaging
148 extern Mutex* JfrBuffer_lock; // protects JFR buffer operations
149 #endif
150
151 extern Mutex* Metaspace_lock; // protects Metaspace virtualspace and chunk expansions
152 extern Monitor* MetaspaceCritical_lock; // synchronizes failed metaspace allocations that risk throwing metaspace OOM
153 extern Mutex* ClassLoaderDataGraph_lock; // protects CLDG list, needed for concurrent unloading
154
155
156 extern Mutex* CodeHeapStateAnalytics_lock; // lock print functions against concurrent analyze functions.
157 // Only used locally in PrintCodeCacheLayout processing.
158
159 extern Mutex* ExternalsRecorder_lock; // used to guard access to the external addresses table
160
161 extern Mutex* AOTCodeCStrings_lock; // used to guard access to the AOT code C strings table
162
163 extern Monitor* ContinuationRelativize_lock;
164
165 #if INCLUDE_JVMCI
166 extern Monitor* JVMCI_lock; // protects global JVMCI critical sections
167 extern Monitor* JVMCIRuntime_lock; // protects critical sections for a specific JVMCIRuntime object
168 #endif
169
170 extern Mutex* Bootclasspath_lock;
171
172 extern Mutex* tty_lock; // lock to synchronize output.
173
174 // A MutexLocker provides mutual exclusion with respect to a given mutex
175 // for the scope which contains the locker. The lock is an OS lock, not
176 // an object lock, and the two do not interoperate. Do not use Mutex-based
177 // locks to lock on Java objects, because they will not be respected if a
178 // that object is locked using the Java locking mechanism.
179 //
180 // NOTE WELL!!
181 //
182 // See orderAccess.hpp. We assume throughout the VM that MutexLocker's
183 // and friends constructors do a fence, a lock and an acquire *in that
184 // order*. And that their destructors do a release and unlock, in *that*
185 // order. If their implementations change such that these assumptions
186 // are violated, a whole lot of code will break.
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
215 MutexLockerImpl(Thread* thread, Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag);
216
217 ~MutexLockerImpl() {
218 if (_mutex != nullptr) {
219 assert_lock_strong(_mutex);
220 _mutex->unlock();
221
222 if (_mutex->id() == -1) {
223 log_trace(init)("Unnamed unclassified lock: %s", _mutex->name());
224 }
225
226 if (_prof) {
227 assert(UsePerfData, "required");
228 _after.stop();
229 _perf_lock_count [_mutex->id() + 1]->inc();
230 _perf_lock_wait_time[_mutex->id() + 1]->inc(_before.ticks());
231 _perf_lock_hold_time[_mutex->id() + 1]->inc(_after.ticks());
232 }
233 }
234 }
235
236 private:
237 static void print_counter_on(outputStream* st, const char* name, bool is_unique, int idx);
238
239 public:
240 static int name2id(const char* name);
241
242 static void post_initialize();
243 static void init_counters();
244 static void print_counters_on(outputStream* st);
245 };
246
247 // Simplest mutex locker.
248 // Does not allow null mutexes.
249 class MutexLocker: public MutexLockerImpl {
250 public:
251 MutexLocker(Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
252 MutexLockerImpl(mutex, flag) {
253 assert(mutex != nullptr, "null mutex not allowed");
254 }
255
256 MutexLocker(Thread* thread, Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
257 MutexLockerImpl(thread, mutex, flag) {
258 assert(mutex != nullptr, "null mutex not allowed");
259 }
260 };
261
262 // Conditional mutex locker.
263 // Like MutexLocker above, but only locks when condition is true.
264 class ConditionalMutexLocker: public MutexLockerImpl {
265 public:
266 ConditionalMutexLocker(Mutex* mutex, bool condition, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
267 MutexLockerImpl(condition ? mutex : nullptr, flag) {
268 assert(!condition || mutex != nullptr, "null mutex not allowed when locking");
269 }
270
271 ConditionalMutexLocker(Thread* thread, Mutex* mutex, bool condition, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
272 MutexLockerImpl(thread, condition ? mutex : nullptr, flag) {
273 assert(!condition || mutex != nullptr, "null mutex not allowed when locking");
274 }
275 };
276
277 // A MonitorLocker is like a MutexLocker above, except it allows
278 // wait/notify as well which are delegated to the underlying Monitor.
279 // It also disallows null.
280 class MonitorLocker: public MutexLockerImpl {
281 Mutex::SafepointCheckFlag _flag;
282
283 protected:
284 Monitor* as_monitor() const {
285 return static_cast<Monitor*>(_mutex);
286 }
287
288 public:
289 MonitorLocker(Monitor* monitor, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
290 MutexLockerImpl(monitor, flag), _flag(flag) {
291 // Superclass constructor did locking
292 assert(monitor != nullptr, "null monitor not allowed");
293 }
294
295 MonitorLocker(Thread* thread, Monitor* monitor, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
296 MutexLockerImpl(thread, monitor, flag), _flag(flag) {
297 // Superclass constructor did locking
298 assert(monitor != nullptr, "null monitor not allowed");
299 }
300
301 bool wait(int64_t timeout = 0) {
302 return _flag == Mutex::_safepoint_check_flag ?
303 as_monitor()->wait(timeout) : as_monitor()->wait_without_safepoint_check(timeout);
304 }
305
306 void notify_all() {
307 as_monitor()->notify_all();
308 }
309
310 void notify() {
311 as_monitor()->notify();
312 }
313 };
314
315
316 // A GCMutexLocker is usually initialized with a mutex that is
317 // automatically acquired in order to do GC. The function that
318 // synchronizes using a GCMutexLocker may be called both during and between
319 // GC's. Thus, it must acquire the mutex if GC is not in progress, but not
320 // if GC is in progress (since the mutex is already held on its behalf.)
321
322 class GCMutexLocker: public StackObj {
323 private:
324 Mutex* _mutex;
325 bool _locked;
326 public:
327 GCMutexLocker(Mutex* mutex);
328 ~GCMutexLocker() { if (_locked) _mutex->unlock(); }
329 };
330
331 // A MutexUnlocker temporarily exits a previously
332 // entered mutex for the scope which contains the unlocker.
333
334 class MutexUnlocker: StackObj {
335 private:
336 Mutex* _mutex;
337 bool _no_safepoint_check;
338
339 public:
340 MutexUnlocker(Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
341 _mutex(mutex),
342 _no_safepoint_check(flag == Mutex::_no_safepoint_check_flag) {
343 _mutex->unlock();
344 }
345
346 ~MutexUnlocker() {
347 if (_no_safepoint_check) {
348 _mutex->lock_without_safepoint_check();
349 } else {
350 _mutex->lock();
351 }
352 }
353 };
354
355 // Instance of a RecursiveLock that may be held through Java heap allocation, which may include calls to Java,
356 // and JNI event notification for resource exhaustion for metaspace or heap.
357 extern RecursiveMutex* MultiArray_lock;
358
359 // RAII locker for a RecursiveMutex. See comments in mutex.hpp for more information.
360 class RecursiveLocker {
361 RecursiveMutex* _lock;
362 Thread* _thread;
363 public:
364 RecursiveLocker(RecursiveMutex* lock, Thread* current) : _lock(lock), _thread(current) {
365 _lock->lock(_thread);
366 }
367 ~RecursiveLocker() {
368 _lock->unlock(_thread);
369 }
370 };
371
372 #endif // SHARE_RUNTIME_MUTEXLOCKER_HPP