1 /* 2 * Copyright (c) 1997, 2021, 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 #ifndef SHARE_RUNTIME_MUTEXLOCKER_HPP 26 #define SHARE_RUNTIME_MUTEXLOCKER_HPP 27 28 #include "memory/allocation.hpp" 29 #include "runtime/flags/flagSetting.hpp" 30 #include "runtime/mutex.hpp" 31 32 // Mutexes used in the VM. 33 34 extern Mutex* Patching_lock; // a lock used to guard code patching of compiled code 35 extern Mutex* CompiledMethod_lock; // a lock used to guard a compiled method and OSR queues 36 extern Monitor* SystemDictionary_lock; // a lock on the system dictionary 37 extern Mutex* SharedDictionary_lock; // a lock on the CDS shared dictionary 38 extern Mutex* Module_lock; // a lock on module and package related data structures 39 extern Mutex* CompiledIC_lock; // a lock used to guard compiled IC patching and access 40 extern Mutex* InlineCacheBuffer_lock; // a lock used to guard the InlineCacheBuffer 41 extern Mutex* VMStatistic_lock; // a lock used to guard statistics count increment 42 extern Mutex* JNIHandleBlockFreeList_lock; // a lock on the JNI handle block free list 43 extern Mutex* JmethodIdCreation_lock; // a lock on creating JNI method identifiers 44 extern Mutex* JfieldIdCreation_lock; // a lock on creating JNI static field identifiers 45 extern Monitor* JNICritical_lock; // a lock used while entering and exiting JNI critical regions, allows GC to sometimes get in 46 extern Mutex* JvmtiThreadState_lock; // a lock on modification of JVMTI thread data 47 extern Monitor* EscapeBarrier_lock; // a lock to sync reallocating and relocking objects because of JVMTI access 48 extern Monitor* Heap_lock; // a lock on the heap 49 extern Mutex* ExpandHeap_lock; // a lock on expanding the heap 50 extern Mutex* AdapterHandlerLibrary_lock; // a lock on the AdapterHandlerLibrary 51 extern Mutex* SignatureHandlerLibrary_lock; // a lock on the SignatureHandlerLibrary 52 extern Mutex* VtableStubs_lock; // a lock on the VtableStubs 53 extern Mutex* SymbolArena_lock; // a lock on the symbol table arena 54 extern Monitor* StringDedup_lock; // a lock on the string deduplication facility 55 extern Mutex* StringDedupIntern_lock; // a lock on StringTable notification of StringDedup 56 extern Monitor* CodeCache_lock; // a lock on the CodeCache, rank is special 57 extern Monitor* CodeSweeper_lock; // a lock used by the sweeper only for wait notify 58 extern Mutex* MethodData_lock; // a lock on installation of method data 59 extern Mutex* TouchedMethodLog_lock; // a lock on allocation of LogExecutedMethods info 60 extern Mutex* RetData_lock; // a lock on installation of RetData inside method data 61 extern Monitor* VMOperation_lock; // a lock on queue of vm_operations waiting to execute 62 extern Monitor* Threads_lock; // a lock on the Threads table of active Java threads 63 // (also used by Safepoints too to block threads creation/destruction) 64 extern Mutex* NonJavaThreadsList_lock; // a lock on the NonJavaThreads list 65 extern Mutex* NonJavaThreadsListSync_lock; // a lock for NonJavaThreads list synchronization 66 extern Monitor* CGC_lock; // used for coordination between 67 // fore- & background GC threads. 68 extern Monitor* STS_lock; // used for joining/leaving SuspendibleThreadSet. 69 extern Monitor* G1OldGCCount_lock; // in support of "concurrent" full gc 70 extern Mutex* Shared_DirtyCardQ_lock; // Lock protecting dirty card 71 // queue shared by 72 // non-Java threads. 73 extern Mutex* G1DetachedRefinementStats_lock; // Lock protecting detached refinement stats 74 extern Mutex* MarkStackFreeList_lock; // Protects access to the global mark stack free list. 75 extern Mutex* MarkStackChunkList_lock; // Protects access to the global mark stack chunk list. 76 extern Mutex* MonitoringSupport_lock; // Protects updates to the serviceability memory pools. 77 extern Mutex* ParGCRareEvent_lock; // Synchronizes various (rare) parallel GC ops. 78 extern Monitor* ConcurrentGCBreakpoints_lock; // Protects concurrent GC breakpoint management 79 extern Mutex* Compile_lock; // a lock held when Compilation is updating code (used to block CodeCache traversal, CHA updates, etc) 80 extern Monitor* MethodCompileQueue_lock; // a lock held when method compilations are enqueued, dequeued 81 extern Monitor* CompileThread_lock; // a lock held by compile threads during compilation system initialization 82 extern Monitor* Compilation_lock; // a lock used to pause compilation 83 extern Mutex* CompileTaskAlloc_lock; // a lock held when CompileTasks are allocated 84 extern Mutex* CompileStatistics_lock; // a lock held when updating compilation statistics 85 extern Mutex* DirectivesStack_lock; // a lock held when mutating the dirstack and ref counting directives 86 extern Mutex* MultiArray_lock; // a lock used to guard allocation of multi-dim arrays 87 extern Monitor* Terminator_lock; // a lock used to guard termination of the vm 88 extern Monitor* InitCompleted_lock; // a lock used to signal threads waiting on init completed 89 extern Monitor* BeforeExit_lock; // a lock used to guard cleanups and shutdown hooks 90 extern Monitor* Notify_lock; // a lock used to synchronize the start-up of the vm 91 extern Mutex* ProfilePrint_lock; // a lock used to serialize the printing of profiles 92 extern Mutex* ExceptionCache_lock; // a lock used to synchronize exception cache updates 93 extern Mutex* NMethodSweeperStats_lock; // a lock used to serialize access to sweeper statistics 94 95 #ifndef PRODUCT 96 extern Mutex* FullGCALot_lock; // a lock to make FullGCALot MT safe 97 #endif // PRODUCT 98 extern Mutex* Debug1_lock; // A bunch of pre-allocated locks that can be used for tracing 99 extern Mutex* Debug2_lock; // down synchronization related bugs! 100 extern Mutex* Debug3_lock; 101 102 extern Mutex* RawMonitor_lock; 103 extern Mutex* PerfDataMemAlloc_lock; // a lock on the allocator for PerfData memory for performance data 104 extern Mutex* PerfDataManager_lock; // a long on access to PerfDataManager resources 105 extern Mutex* OopMapCacheAlloc_lock; // protects allocation of oop_map caches 106 107 extern Mutex* FreeList_lock; // protects the free region list during safepoints 108 extern Mutex* OldSets_lock; // protects the old region sets 109 extern Mutex* Uncommit_lock; // protects the uncommit list when not at safepoints 110 extern Monitor* RootRegionScan_lock; // used to notify that the CM threads have finished scanning the IM snapshot regions 111 112 extern Mutex* Management_lock; // a lock used to serialize JVM management 113 extern Monitor* MonitorDeflation_lock; // a lock used for monitor deflation thread operation 114 extern Monitor* Service_lock; // a lock used for service thread operation 115 extern Monitor* Notification_lock; // a lock used for notification thread operation 116 extern Monitor* PeriodicTask_lock; // protects the periodic task structure 117 extern Monitor* RedefineClasses_lock; // locks classes from parallel redefinition 118 extern Mutex* Verify_lock; // synchronize initialization of verify library 119 extern Monitor* Zip_lock; // synchronize initialization of zip library 120 extern Monitor* ThreadsSMRDelete_lock; // Used by ThreadsSMRSupport to take pressure off the Threads_lock 121 extern Mutex* ThreadIdTableCreate_lock; // Used by ThreadIdTable to lazily create the thread id table 122 extern Mutex* SharedDecoder_lock; // serializes access to the decoder during normal (not error reporting) use 123 extern Mutex* DCmdFactory_lock; // serialize access to DCmdFactory information 124 #if INCLUDE_NMT 125 extern Mutex* NMTQuery_lock; // serialize NMT Dcmd queries 126 #endif 127 #if INCLUDE_CDS 128 #if INCLUDE_JVMTI 129 extern Mutex* CDSClassFileStream_lock; // FileMapInfo::open_stream_for_jvmti 130 #endif 131 extern Mutex* DumpTimeTable_lock; // SystemDictionaryShared::find_or_allocate_info_for 132 extern Mutex* CDSLambda_lock; // SystemDictionaryShared::get_shared_lambda_proxy_class 133 extern Mutex* DumpRegion_lock; // Symbol::operator new(size_t sz, int len) 134 extern Mutex* ClassListFile_lock; // ClassListWriter() 135 extern Mutex* LambdaFormInvokers_lock; // Protecting LambdaFormInvokers::_lambdaform_lines 136 #endif // INCLUDE_CDS 137 #if INCLUDE_JFR 138 extern Mutex* JfrStacktrace_lock; // used to guard access to the JFR stacktrace table 139 extern Monitor* JfrMsg_lock; // protects JFR messaging 140 extern Mutex* JfrBuffer_lock; // protects JFR buffer operations 141 extern Mutex* JfrStream_lock; // protects JFR stream access 142 extern Monitor* JfrThreadSampler_lock; // used to suspend/resume JFR thread sampler 143 #endif 144 145 #ifndef SUPPORTS_NATIVE_CX8 146 extern Mutex* UnsafeJlong_lock; // provides Unsafe atomic updates to jlongs on platforms that don't support cx8 147 #endif 148 149 extern Mutex* Metaspace_lock; // protects Metaspace virtualspace and chunk expansions 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 #if INCLUDE_JVMCI 157 extern Monitor* JVMCI_lock; // Monitor to control initialization of JVMCI 158 #endif 159 160 extern Mutex* Bootclasspath_lock; 161 162 extern Mutex* tty_lock; // lock to synchronize output. 163 164 // A MutexLocker provides mutual exclusion with respect to a given mutex 165 // for the scope which contains the locker. The lock is an OS lock, not 166 // an object lock, and the two do not interoperate. Do not use Mutex-based 167 // locks to lock on Java objects, because they will not be respected if a 168 // that object is locked using the Java locking mechanism. 169 // 170 // NOTE WELL!! 171 // 172 // See orderAccess.hpp. We assume throughout the VM that MutexLocker's 173 // and friends constructors do a fence, a lock and an acquire *in that 174 // order*. And that their destructors do a release and unlock, in *that* 175 // order. If their implementations change such that these assumptions 176 // are violated, a whole lot of code will break. 177 178 // Print all mutexes/monitors that are currently owned by a thread; called 179 // by fatal error handler. 180 void print_owned_locks_on_error(outputStream* st); 181 182 char *lock_name(Mutex *mutex); 183 184 // for debugging: check that we're already owning this lock (or are at a safepoint / handshake) 185 #ifdef ASSERT 186 void assert_locked_or_safepoint(const Mutex* lock); 187 void assert_locked_or_safepoint_weak(const Mutex* lock); 188 void assert_lock_strong(const Mutex* lock); 189 void assert_locked_or_safepoint_or_handshake(const Mutex* lock, const JavaThread* thread); 190 #else 191 #define assert_locked_or_safepoint(lock) 192 #define assert_locked_or_safepoint_weak(lock) 193 #define assert_lock_strong(lock) 194 #define assert_locked_or_safepoint_or_handshake(lock, thread) 195 #endif 196 197 class MutexLocker: public StackObj { 198 protected: 199 Mutex* _mutex; 200 public: MutexLocker(Mutex * mutex,Mutex::SafepointCheckFlag flag=Mutex::_safepoint_check_flag)201 MutexLocker(Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) : 202 _mutex(mutex) { 203 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag; 204 if (_mutex != NULL) { 205 assert(_mutex->rank() > Mutex::special || no_safepoint_check, 206 "Mutexes with rank special or lower should not do safepoint checks"); 207 if (no_safepoint_check) { 208 _mutex->lock_without_safepoint_check(); 209 } else { 210 _mutex->lock(); 211 } 212 } 213 } 214 MutexLocker(Thread * thread,Mutex * mutex,Mutex::SafepointCheckFlag flag=Mutex::_safepoint_check_flag)215 MutexLocker(Thread* thread, Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) : 216 _mutex(mutex) { 217 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag; 218 if (_mutex != NULL) { 219 assert(_mutex->rank() > Mutex::special || no_safepoint_check, 220 "Mutexes with rank special or lower should not do safepoint checks"); 221 if (no_safepoint_check) { 222 _mutex->lock_without_safepoint_check(thread); 223 } else { 224 _mutex->lock(thread); 225 } 226 } 227 } 228 ~MutexLocker()229 ~MutexLocker() { 230 if (_mutex != NULL) { 231 assert_lock_strong(_mutex); 232 _mutex->unlock(); 233 } 234 } 235 }; 236 237 // A MonitorLocker is like a MutexLocker above, except it allows 238 // wait/notify as well which are delegated to the underlying Monitor. 239 // It also disallows NULL. 240 241 class MonitorLocker: public MutexLocker { 242 Mutex::SafepointCheckFlag _flag; 243 244 protected: as_monitor() const245 Monitor* as_monitor() const { 246 return static_cast<Monitor*>(_mutex); 247 } 248 249 public: MonitorLocker(Monitor * monitor,Mutex::SafepointCheckFlag flag=Mutex::_safepoint_check_flag)250 MonitorLocker(Monitor* monitor, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) : 251 MutexLocker(monitor, flag), _flag(flag) { 252 // Superclass constructor did locking 253 assert(monitor != NULL, "NULL monitor not allowed"); 254 } 255 MonitorLocker(Thread * thread,Monitor * monitor,Mutex::SafepointCheckFlag flag=Mutex::_safepoint_check_flag)256 MonitorLocker(Thread* thread, Monitor* monitor, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) : 257 MutexLocker(thread, monitor, flag), _flag(flag) { 258 // Superclass constructor did locking 259 assert(monitor != NULL, "NULL monitor not allowed"); 260 } 261 wait(int64_t timeout=0)262 bool wait(int64_t timeout = 0) { 263 return _flag == Mutex::_safepoint_check_flag ? 264 as_monitor()->wait(timeout) : as_monitor()->wait_without_safepoint_check(timeout); 265 } 266 notify_all()267 void notify_all() { 268 as_monitor()->notify_all(); 269 } 270 notify()271 void notify() { 272 as_monitor()->notify(); 273 } 274 }; 275 276 277 // A GCMutexLocker is usually initialized with a mutex that is 278 // automatically acquired in order to do GC. The function that 279 // synchronizes using a GCMutexLocker may be called both during and between 280 // GC's. Thus, it must acquire the mutex if GC is not in progress, but not 281 // if GC is in progress (since the mutex is already held on its behalf.) 282 283 class GCMutexLocker: public StackObj { 284 private: 285 Mutex* _mutex; 286 bool _locked; 287 public: 288 GCMutexLocker(Mutex* mutex); ~GCMutexLocker()289 ~GCMutexLocker() { if (_locked) _mutex->unlock(); } 290 }; 291 292 // A MutexUnlocker temporarily exits a previously 293 // entered mutex for the scope which contains the unlocker. 294 295 class MutexUnlocker: StackObj { 296 private: 297 Mutex* _mutex; 298 bool _no_safepoint_check; 299 300 public: MutexUnlocker(Mutex * mutex,Mutex::SafepointCheckFlag flag=Mutex::_safepoint_check_flag)301 MutexUnlocker(Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) : 302 _mutex(mutex), 303 _no_safepoint_check(flag == Mutex::_no_safepoint_check_flag) { 304 _mutex->unlock(); 305 } 306 ~MutexUnlocker()307 ~MutexUnlocker() { 308 if (_no_safepoint_check) { 309 _mutex->lock_without_safepoint_check(); 310 } else { 311 _mutex->lock(); 312 } 313 } 314 }; 315 316 #endif // SHARE_RUNTIME_MUTEXLOCKER_HPP 317