1 /* 2 * Copyright (c) 1997, 2020, 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* ProtectionDomainSet_lock; // a lock on the pd_set list in the system dictionary 38 extern Mutex* SharedDictionary_lock; // a lock on the CDS shared dictionary 39 extern Mutex* Module_lock; // a lock on module and package related data structures 40 extern Mutex* CompiledIC_lock; // a lock used to guard compiled IC patching and access 41 extern Mutex* InlineCacheBuffer_lock; // a lock used to guard the InlineCacheBuffer 42 extern Mutex* VMStatistic_lock; // a lock used to guard statistics count increment 43 extern Mutex* JNIHandleBlockFreeList_lock; // a lock on the JNI handle block free list 44 extern Mutex* JmethodIdCreation_lock; // a lock on creating JNI method identifiers 45 extern Mutex* JfieldIdCreation_lock; // a lock on creating JNI static field identifiers 46 extern Monitor* JNICritical_lock; // a lock used while entering and exiting JNI critical regions, allows GC to sometimes get in 47 extern Mutex* JvmtiThreadState_lock; // a lock on modification of JVMTI thread data 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* StringDedupQueue_lock; // a lock on the string deduplication queue 55 extern Mutex* StringDedupTable_lock; // a lock on the string deduplication table 56 extern Monitor* CodeCache_lock; // a lock on the CodeCache, rank is special 57 extern Mutex* MethodData_lock; // a lock on installation of method data 58 extern Mutex* TouchedMethodLog_lock; // a lock on allocation of LogExecutedMethods info 59 extern Mutex* RetData_lock; // a lock on installation of RetData inside method data 60 extern Monitor* VMOperationQueue_lock; // a lock on queue of vm_operations waiting to execute 61 extern Monitor* VMOperationRequest_lock; // a lock on Threads waiting for a vm_operation to terminate 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* FullGCCount_lock; // in support of "concurrent" full gc 70 extern Monitor* G1OldGCCount_lock; // in support of "concurrent" full gc 71 extern Mutex* Shared_DirtyCardQ_lock; // Lock protecting dirty card 72 // queue shared by 73 // non-Java threads. 74 extern Mutex* G1DetachedRefinementStats_lock; // Lock protecting detached refinement stats 75 extern Mutex* MarkStackFreeList_lock; // Protects access to the global mark stack free list. 76 extern Mutex* MarkStackChunkList_lock; // Protects access to the global mark stack chunk list. 77 extern Mutex* MonitoringSupport_lock; // Protects updates to the serviceability memory pools. 78 extern Mutex* ParGCRareEvent_lock; // Synchronizes various (rare) parallel GC ops. 79 extern Monitor* ConcurrentGCBreakpoints_lock; // Protects concurrent GC breakpoint management 80 extern Mutex* Compile_lock; // a lock held when Compilation is updating code (used to block CodeCache traversal, CHA updates, etc) 81 extern Monitor* MethodCompileQueue_lock; // a lock held when method compilations are enqueued, dequeued 82 extern Monitor* CompileThread_lock; // a lock held by compile threads during compilation system initialization 83 extern Monitor* Compilation_lock; // a lock used to pause compilation 84 extern Mutex* CompileTaskAlloc_lock; // a lock held when CompileTasks are allocated 85 extern Mutex* CompileStatistics_lock; // a lock held when updating compilation statistics 86 extern Mutex* DirectivesStack_lock; // a lock held when mutating the dirstack and ref counting directives 87 extern Mutex* MultiArray_lock; // a lock used to guard allocation of multi-dim arrays 88 extern Monitor* Terminator_lock; // a lock used to guard termination of the vm 89 extern Monitor* InitCompleted_lock; // a lock used to signal threads waiting on init completed 90 extern Monitor* BeforeExit_lock; // a lock used to guard cleanups and shutdown hooks 91 extern Monitor* Notify_lock; // a lock used to synchronize the start-up of the vm 92 extern Mutex* ProfilePrint_lock; // a lock used to serialize the printing of profiles 93 extern Mutex* ExceptionCache_lock; // a lock used to synchronize exception cache updates 94 extern Mutex* NMethodSweeperStats_lock; // a lock used to serialize access to sweeper statistics 95 96 #ifndef PRODUCT 97 extern Mutex* FullGCALot_lock; // a lock to make FullGCALot MT safe 98 #endif // PRODUCT 99 extern Mutex* Debug1_lock; // A bunch of pre-allocated locks that can be used for tracing 100 extern Mutex* Debug2_lock; // down synchronization related bugs! 101 extern Mutex* Debug3_lock; 102 103 extern Mutex* RawMonitor_lock; 104 extern Mutex* PerfDataMemAlloc_lock; // a lock on the allocator for PerfData memory for performance data 105 extern Mutex* PerfDataManager_lock; // a long on access to PerfDataManager resources 106 extern Mutex* OopMapCacheAlloc_lock; // protects allocation of oop_map caches 107 108 extern Mutex* FreeList_lock; // protects the free region list during safepoints 109 extern Mutex* OldSets_lock; // protects the old region sets 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* Service_lock; // a lock used for service thread operation 114 extern Monitor* Notification_lock; // a lock used for notification thread operation 115 extern Monitor* PeriodicTask_lock; // protects the periodic task structure 116 extern Monitor* RedefineClasses_lock; // locks classes from parallel redefinition 117 extern Mutex* Verify_lock; // synchronize initialization of verify library 118 extern Monitor* Zip_lock; // synchronize initialization of zip library 119 extern Monitor* ThreadsSMRDelete_lock; // Used by ThreadsSMRSupport to take pressure off the Threads_lock 120 extern Mutex* ThreadIdTableCreate_lock; // Used by ThreadIdTable to lazily create the thread id table 121 extern Mutex* SharedDecoder_lock; // serializes access to the decoder during normal (not error reporting) use 122 extern Mutex* DCmdFactory_lock; // serialize access to DCmdFactory information 123 #if INCLUDE_NMT 124 extern Mutex* NMTQuery_lock; // serialize NMT Dcmd queries 125 #endif 126 #if INCLUDE_CDS 127 #if INCLUDE_JVMTI 128 extern Mutex* CDSClassFileStream_lock; // FileMapInfo::open_stream_for_jvmti 129 #endif 130 extern Mutex* DumpTimeTable_lock; // SystemDictionaryShared::find_or_allocate_info_for 131 #endif // INCLUDE_CDS 132 #if INCLUDE_JFR 133 extern Mutex* JfrStacktrace_lock; // used to guard access to the JFR stacktrace table 134 extern Monitor* JfrMsg_lock; // protects JFR messaging 135 extern Mutex* JfrBuffer_lock; // protects JFR buffer operations 136 extern Mutex* JfrStream_lock; // protects JFR stream access 137 extern Monitor* JfrThreadSampler_lock; // used to suspend/resume JFR thread sampler 138 #endif 139 140 #ifndef SUPPORTS_NATIVE_CX8 141 extern Mutex* UnsafeJlong_lock; // provides Unsafe atomic updates to jlongs on platforms that don't support cx8 142 #endif 143 144 extern Mutex* MetaspaceExpand_lock; // protects Metaspace virtualspace and chunk expansions 145 extern Mutex* ClassLoaderDataGraph_lock; // protects CLDG list, needed for concurrent unloading 146 147 148 extern Mutex* CodeHeapStateAnalytics_lock; // lock print functions against concurrent analyze functions. 149 // Only used locally in PrintCodeCacheLayout processing. 150 151 #if INCLUDE_JVMCI 152 extern Monitor* JVMCI_lock; // Monitor to control initialization of JVMCI 153 #endif 154 155 extern Mutex* tty_lock; // lock to synchronize output. 156 157 // A MutexLocker provides mutual exclusion with respect to a given mutex 158 // for the scope which contains the locker. The lock is an OS lock, not 159 // an object lock, and the two do not interoperate. Do not use Mutex-based 160 // locks to lock on Java objects, because they will not be respected if a 161 // that object is locked using the Java locking mechanism. 162 // 163 // NOTE WELL!! 164 // 165 // See orderAccess.hpp. We assume throughout the VM that MutexLocker's 166 // and friends constructors do a fence, a lock and an acquire *in that 167 // order*. And that their destructors do a release and unlock, in *that* 168 // order. If their implementations change such that these assumptions 169 // are violated, a whole lot of code will break. 170 171 // Print all mutexes/monitors that are currently owned by a thread; called 172 // by fatal error handler. 173 void print_owned_locks_on_error(outputStream* st); 174 175 char *lock_name(Mutex *mutex); 176 177 // for debugging: check that we're already owning this lock (or are at a safepoint / handshake) 178 #ifdef ASSERT 179 void assert_locked_or_safepoint(const Mutex* lock); 180 void assert_locked_or_safepoint_weak(const Mutex* lock); 181 void assert_lock_strong(const Mutex* lock); 182 void assert_locked_or_safepoint_or_handshake(const Mutex* lock, const JavaThread* thread); 183 #else 184 #define assert_locked_or_safepoint(lock) 185 #define assert_locked_or_safepoint_weak(lock) 186 #define assert_lock_strong(lock) 187 #define assert_locked_or_safepoint_or_handshake(lock, thread) 188 #endif 189 190 class MutexLocker: public StackObj { 191 protected: 192 Mutex* _mutex; 193 private: 194 public: 195 MutexLocker(Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) : 196 _mutex(mutex) { 197 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag; 198 if (_mutex != NULL) { 199 assert(_mutex->rank() > Mutex::special || no_safepoint_check, 200 "Mutexes with rank special or lower should not do safepoint checks"); 201 if (no_safepoint_check) { 202 _mutex->lock_without_safepoint_check(); 203 } else { 204 _mutex->lock(); 205 } 206 } 207 } 208 209 MutexLocker(Thread* thread, Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) : 210 _mutex(mutex) { 211 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag; 212 if (_mutex != NULL) { 213 assert(_mutex->rank() > Mutex::special || no_safepoint_check, 214 "Mutexes with rank special or lower should not do safepoint checks"); 215 if (no_safepoint_check) { 216 _mutex->lock_without_safepoint_check(thread); 217 } else { 218 _mutex->lock(thread); 219 } 220 } 221 } 222 223 ~MutexLocker() { 224 if (_mutex != NULL) { 225 assert_lock_strong(_mutex); 226 _mutex->unlock(); 227 } 228 } 229 }; 230 231 // A MonitorLocker is like a MutexLocker above, except it allows 232 // wait/notify as well which are delegated to the underlying Monitor. 233 // It also disallows NULL. 234 235 class MonitorLocker: public MutexLocker { 236 Mutex::SafepointCheckFlag _flag; 237 Monitor* _monitor; 238 public: 239 MonitorLocker(Monitor* monitor, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) : 240 MutexLocker(monitor, flag), _flag(flag), _monitor(monitor) { 241 // Superclass constructor did locking 242 assert(_monitor != NULL, "NULL monitor not allowed"); 243 } 244 245 MonitorLocker(Thread* thread, Monitor* monitor, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) : 246 MutexLocker(thread, monitor, flag), _flag(flag), _monitor(monitor) { 247 // Superclass constructor did locking 248 assert(_monitor != NULL, "NULL monitor not allowed"); 249 } 250 251 bool wait(long timeout = 0, 252 bool as_suspend_equivalent = !Mutex::_as_suspend_equivalent_flag) { 253 if (_flag == Mutex::_safepoint_check_flag) { 254 return _monitor->wait(timeout, as_suspend_equivalent); 255 } else { 256 return _monitor->wait_without_safepoint_check(timeout); 257 } 258 return false; 259 } 260 261 void notify_all() { 262 _monitor->notify_all(); 263 } 264 265 void notify() { 266 _monitor->notify(); 267 } 268 }; 269 270 271 // A GCMutexLocker is usually initialized with a mutex that is 272 // automatically acquired in order to do GC. The function that 273 // synchronizes using a GCMutexLocker may be called both during and between 274 // GC's. Thus, it must acquire the mutex if GC is not in progress, but not 275 // if GC is in progress (since the mutex is already held on its behalf.) 276 277 class GCMutexLocker: public StackObj { 278 private: 279 Mutex* _mutex; 280 bool _locked; 281 public: 282 GCMutexLocker(Mutex* mutex); 283 ~GCMutexLocker() { if (_locked) _mutex->unlock(); } 284 }; 285 286 // A MutexUnlocker temporarily exits a previously 287 // entered mutex for the scope which contains the unlocker. 288 289 class MutexUnlocker: StackObj { 290 private: 291 Mutex* _mutex; 292 bool _no_safepoint_check; 293 294 public: 295 MutexUnlocker(Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) : 296 _mutex(mutex), 297 _no_safepoint_check(flag) { 298 _mutex->unlock(); 299 } 300 301 ~MutexUnlocker() { 302 if (_no_safepoint_check) { 303 _mutex->lock_without_safepoint_check(); 304 } else { 305 _mutex->lock(); 306 } 307 } 308 }; 309 310 #endif // SHARE_RUNTIME_MUTEXLOCKER_HPP