1 /* 2 * Copyright (c) 1997, 2019, 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 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* JNIGlobalAlloc_lock; // JNI global storage allocate list lock 44 extern Mutex* JNIGlobalActive_lock; // JNI global storage active list lock 45 extern Mutex* JNIWeakAlloc_lock; // JNI weak storage allocate list lock 46 extern Mutex* JNIWeakActive_lock; // JNI weak storage active list lock 47 extern Mutex* StringTableWeakAlloc_lock; // StringTable weak storage allocate list lock 48 extern Mutex* StringTableWeakActive_lock; // STringTable weak storage active list lock 49 extern Mutex* JNIHandleBlockFreeList_lock; // a lock on the JNI handle block free list 50 extern Mutex* VMWeakAlloc_lock; // VM Weak Handles storage allocate list lock 51 extern Mutex* VMWeakActive_lock; // VM Weak Handles storage active list lock 52 extern Mutex* ResolvedMethodTableWeakAlloc_lock; // ResolvedMethodTable weak storage allocate list 53 extern Mutex* ResolvedMethodTableWeakActive_lock; // ResolvedMethodTable weak storage active list 54 extern Mutex* JmethodIdCreation_lock; // a lock on creating JNI method identifiers 55 extern Mutex* JfieldIdCreation_lock; // a lock on creating JNI static field identifiers 56 extern Monitor* JNICritical_lock; // a lock used while entering and exiting JNI critical regions, allows GC to sometimes get in 57 extern Mutex* JvmtiThreadState_lock; // a lock on modification of JVMTI thread data 58 extern Monitor* Heap_lock; // a lock on the heap 59 extern Mutex* ExpandHeap_lock; // a lock on expanding the heap 60 extern Mutex* AdapterHandlerLibrary_lock; // a lock on the AdapterHandlerLibrary 61 extern Mutex* SignatureHandlerLibrary_lock; // a lock on the SignatureHandlerLibrary 62 extern Mutex* VtableStubs_lock; // a lock on the VtableStubs 63 extern Mutex* SymbolArena_lock; // a lock on the symbol table arena 64 extern Monitor* StringDedupQueue_lock; // a lock on the string deduplication queue 65 extern Mutex* StringDedupTable_lock; // a lock on the string deduplication table 66 extern Monitor* CodeCache_lock; // a lock on the CodeCache, rank is special 67 extern Mutex* MethodData_lock; // a lock on installation of method data 68 extern Mutex* TouchedMethodLog_lock; // a lock on allocation of LogExecutedMethods info 69 extern Mutex* RetData_lock; // a lock on installation of RetData inside method data 70 extern Monitor* CGCPhaseManager_lock; // a lock to protect a concurrent GC's phase management 71 extern Monitor* VMOperationQueue_lock; // a lock on queue of vm_operations waiting to execute 72 extern Monitor* VMOperationRequest_lock; // a lock on Threads waiting for a vm_operation to terminate 73 extern Monitor* Threads_lock; // a lock on the Threads table of active Java threads 74 // (also used by Safepoints too to block threads creation/destruction) 75 extern Mutex* NonJavaThreadsList_lock; // a lock on the NonJavaThreads list 76 extern Mutex* NonJavaThreadsListSync_lock; // a lock for NonJavaThreads list synchronization 77 extern Monitor* CGC_lock; // used for coordination between 78 // fore- & background GC threads. 79 extern Monitor* STS_lock; // used for joining/leaving SuspendibleThreadSet. 80 extern Monitor* FullGCCount_lock; // in support of "concurrent" full gc 81 extern Monitor* SATB_Q_CBL_mon; // Protects SATB Q 82 // completed buffer queue. 83 extern Monitor* DirtyCardQ_CBL_mon; // Protects dirty card Q 84 // completed buffer queue. 85 extern Mutex* Shared_DirtyCardQ_lock; // Lock protecting dirty card 86 // queue shared by 87 // non-Java threads. 88 extern Mutex* MarkStackFreeList_lock; // Protects access to the global mark stack free list. 89 extern Mutex* MarkStackChunkList_lock; // Protects access to the global mark stack chunk list. 90 extern Mutex* MonitoringSupport_lock; // Protects updates to the serviceability memory pools. 91 extern Mutex* ParGCRareEvent_lock; // Synchronizes various (rare) parallel GC ops. 92 extern Mutex* Compile_lock; // a lock held when Compilation is updating code (used to block CodeCache traversal, CHA updates, etc) 93 extern Monitor* MethodCompileQueue_lock; // a lock held when method compilations are enqueued, dequeued 94 extern Monitor* CompileThread_lock; // a lock held by compile threads during compilation system initialization 95 extern Monitor* Compilation_lock; // a lock used to pause compilation 96 extern Mutex* CompileTaskAlloc_lock; // a lock held when CompileTasks are allocated 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 Mutex* MultiArray_lock; // a lock used to guard allocation of multi-dim arrays 100 extern Monitor* Terminator_lock; // a lock used to guard termination of the vm 101 extern Monitor* InitCompleted_lock; // a lock used to signal threads waiting on init completed 102 extern Monitor* BeforeExit_lock; // a lock used to guard cleanups and shutdown hooks 103 extern Monitor* Notify_lock; // a lock used to synchronize the start-up of the vm 104 extern Mutex* ProfilePrint_lock; // a lock used to serialize the printing of profiles 105 extern Mutex* ExceptionCache_lock; // a lock used to synchronize exception cache updates 106 extern Mutex* OsrList_lock; // a lock used to serialize access to OSR queues 107 extern Mutex* NMethodSweeperStats_lock; // a lock used to serialize access to sweeper statistics 108 109 #ifndef PRODUCT 110 extern Mutex* FullGCALot_lock; // a lock to make FullGCALot MT safe 111 #endif // PRODUCT 112 extern Mutex* Debug1_lock; // A bunch of pre-allocated locks that can be used for tracing 113 extern Mutex* Debug2_lock; // down synchronization related bugs! 114 extern Mutex* Debug3_lock; 115 116 extern Mutex* RawMonitor_lock; 117 extern Mutex* PerfDataMemAlloc_lock; // a lock on the allocator for PerfData memory for performance data 118 extern Mutex* PerfDataManager_lock; // a long on access to PerfDataManager resources 119 extern Mutex* ParkerFreeList_lock; 120 extern Mutex* OopMapCacheAlloc_lock; // protects allocation of oop_map caches 121 122 extern Mutex* FreeList_lock; // protects the free region list during safepoints 123 extern Mutex* OldSets_lock; // protects the old region sets 124 extern Monitor* RootRegionScan_lock; // used to notify that the CM threads have finished scanning the IM snapshot regions 125 126 extern Mutex* Management_lock; // a lock used to serialize JVM management 127 extern Monitor* Service_lock; // a lock used for service thread operation 128 extern Monitor* PeriodicTask_lock; // protects the periodic task structure 129 extern Monitor* RedefineClasses_lock; // locks classes from parallel redefinition 130 extern Monitor* ThreadsSMRDelete_lock; // Used by ThreadsSMRSupport to take pressure off the Threads_lock 131 extern Mutex* SharedDecoder_lock; // serializes access to the decoder during normal (not error reporting) use 132 extern Mutex* DCmdFactory_lock; // serialize access to DCmdFactory information 133 #if INCLUDE_NMT 134 extern Mutex* NMTQuery_lock; // serialize NMT Dcmd queries 135 #endif 136 #if INCLUDE_CDS 137 #if INCLUDE_JVMTI 138 extern Mutex* CDSClassFileStream_lock; // FileMapInfo::open_stream_for_jvmti 139 #endif 140 extern Mutex* DumpTimeTable_lock; // SystemDictionaryShared::find_or_allocate_info_for 141 #endif // INCLUDE_CDS 142 #if INCLUDE_JFR 143 extern Mutex* JfrStacktrace_lock; // used to guard access to the JFR stacktrace table 144 extern Monitor* JfrMsg_lock; // protects JFR messaging 145 extern Mutex* JfrBuffer_lock; // protects JFR buffer operations 146 extern Mutex* JfrStream_lock; // protects JFR stream access 147 extern Monitor* JfrThreadSampler_lock; // used to suspend/resume JFR thread sampler 148 #endif 149 150 #ifndef SUPPORTS_NATIVE_CX8 151 extern Mutex* UnsafeJlong_lock; // provides Unsafe atomic updates to jlongs on platforms that don't support cx8 152 #endif 153 154 extern Mutex* MetaspaceExpand_lock; // protects Metaspace virtualspace and chunk expansions 155 extern Mutex* ClassLoaderDataGraph_lock; // protects CLDG list, needed for concurrent unloading 156 157 158 extern Monitor* CodeHeapStateAnalytics_lock; // lock print functions against concurrent analyze functions. 159 // Only used locally in PrintCodeCacheLayout processing. 160 161 #if INCLUDE_JVMCI 162 extern Monitor* JVMCI_lock; // Monitor to control initialization of JVMCI 163 extern Mutex* JVMCIGlobalAlloc_lock; // JVMCI global storage allocate list lock 164 extern Mutex* JVMCIGlobalActive_lock; // JVMCI global storage active list lock 165 #endif 166 167 // A MutexLocker provides mutual exclusion with respect to a given mutex 168 // for the scope which contains the locker. The lock is an OS lock, not 169 // an object lock, and the two do not interoperate. Do not use Mutex-based 170 // locks to lock on Java objects, because they will not be respected if a 171 // that object is locked using the Java locking mechanism. 172 // 173 // NOTE WELL!! 174 // 175 // See orderAccess.hpp. We assume throughout the VM that MutexLocker's 176 // and friends constructors do a fence, a lock and an acquire *in that 177 // order*. And that their destructors do a release and unlock, in *that* 178 // order. If their implementations change such that these assumptions 179 // are violated, a whole lot of code will break. 180 181 // Print all mutexes/monitors that are currently owned by a thread; called 182 // by fatal error handler. 183 void print_owned_locks_on_error(outputStream* st); 184 185 char *lock_name(Mutex *mutex); 186 187 // for debugging: check that we're already owning this lock (or are at a safepoint) 188 #ifdef ASSERT 189 void assert_locked_or_safepoint(const Monitor * lock); 190 void assert_locked_or_safepoint_weak(const Monitor * lock); 191 void assert_lock_strong(const Monitor * lock); 192 #else 193 #define assert_locked_or_safepoint(lock) 194 #define assert_locked_or_safepoint_weak(lock) 195 #define assert_lock_strong(lock) 196 #endif 197 198 class MutexLocker: public StackObj { 199 protected: 200 Monitor* _mutex; 201 private: 202 public: 203 MutexLocker(Monitor* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) : 204 _mutex(mutex) { 205 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag; 206 if (_mutex != NULL) { 207 assert(_mutex->rank() > Mutex::special || no_safepoint_check, 208 "Mutexes with rank special or lower should not do safepoint checks"); 209 if (no_safepoint_check) { 210 _mutex->lock_without_safepoint_check(); 211 } else { 212 _mutex->lock(); 213 } 214 } 215 } 216 217 MutexLocker(Monitor* mutex, Thread* thread, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) : 218 _mutex(mutex) { 219 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag; 220 if (_mutex != NULL) { 221 assert(_mutex->rank() > Mutex::special || no_safepoint_check, 222 "Mutexes with rank special or lower should not do safepoint checks"); 223 if (no_safepoint_check) { 224 _mutex->lock_without_safepoint_check(thread); 225 } else { 226 _mutex->lock(thread); 227 } 228 } 229 } 230 231 ~MutexLocker() { 232 if (_mutex != NULL) { 233 assert_lock_strong(_mutex); 234 _mutex->unlock(); 235 } 236 } 237 }; 238 239 // A MonitorLocker is like a MutexLocker above, except it allows 240 // wait/notify as well which are delegated to the underlying Monitor. 241 // It also disallows NULL. 242 243 class MonitorLocker: public MutexLocker { 244 Mutex::SafepointCheckFlag _flag; 245 public: 246 MonitorLocker(Monitor* monitor, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) : 247 MutexLocker(monitor, flag), _flag(flag) { 248 // Superclass constructor did locking 249 assert(_mutex != NULL, "NULL monitor not allowed"); 250 } 251 252 MonitorLocker(Monitor* monitor, Thread* thread, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) : 253 MutexLocker(monitor, thread, flag), _flag(flag) { 254 // Superclass constructor did locking 255 assert(_mutex != NULL, "NULL monitor not allowed"); 256 } 257 258 bool wait(long timeout = 0, 259 bool as_suspend_equivalent = !Mutex::_as_suspend_equivalent_flag) { 260 if (_flag == Mutex::_safepoint_check_flag) { 261 return _mutex->wait(timeout, as_suspend_equivalent); 262 } else { 263 return _mutex->wait_without_safepoint_check(timeout); 264 } 265 return false; 266 } 267 268 void notify_all() { 269 _mutex->notify_all(); 270 } 271 272 void notify() { 273 _mutex->notify(); 274 } 275 }; 276 277 278 // A GCMutexLocker is usually initialized with a mutex that is 279 // automatically acquired in order to do GC. The function that 280 // synchronizes using a GCMutexLocker may be called both during and between 281 // GC's. Thus, it must acquire the mutex if GC is not in progress, but not 282 // if GC is in progress (since the mutex is already held on its behalf.) 283 284 class GCMutexLocker: public StackObj { 285 private: 286 Monitor* _mutex; 287 bool _locked; 288 public: 289 GCMutexLocker(Monitor* mutex); 290 ~GCMutexLocker() { if (_locked) _mutex->unlock(); } 291 }; 292 293 // A MutexUnlocker temporarily exits a previously 294 // entered mutex for the scope which contains the unlocker. 295 296 class MutexUnlocker: StackObj { 297 private: 298 Monitor* _mutex; 299 bool _no_safepoint_check; 300 301 public: 302 MutexUnlocker(Monitor* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) : 303 _mutex(mutex), 304 _no_safepoint_check(flag) { 305 _mutex->unlock(); 306 } 307 308 ~MutexUnlocker() { 309 if (_no_safepoint_check) { 310 _mutex->lock_without_safepoint_check(); 311 } else { 312 _mutex->lock(); 313 } 314 } 315 }; 316 317 #endif // SHARE_RUNTIME_MUTEXLOCKER_HPP