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 #include "precompiled.hpp" 26 #include "memory/universe.hpp" 27 #include "runtime/mutexLocker.hpp" 28 #include "runtime/os.inline.hpp" 29 #include "runtime/safepoint.hpp" 30 #include "runtime/thread.inline.hpp" 31 #include "runtime/vmThread.hpp" 32 33 // Mutexes used in the VM (see comment in mutexLocker.hpp): 34 // 35 // Note that the following pointers are effectively final -- after having been 36 // set at JVM startup-time, they should never be subsequently mutated. 37 // Instead of using pointers to malloc()ed monitors and mutexes we should consider 38 // eliminating the indirection and using instances instead. 39 // Consider using GCC's __read_mostly. 40 41 Mutex* Patching_lock = NULL; 42 Monitor* SystemDictionary_lock = NULL; 43 Mutex* ProtectionDomainSet_lock = NULL; 44 Mutex* SharedDictionary_lock = NULL; 45 Mutex* Module_lock = NULL; 46 Mutex* CompiledIC_lock = NULL; 47 Mutex* InlineCacheBuffer_lock = NULL; 48 Mutex* VMStatistic_lock = NULL; 49 Mutex* JNIGlobalAlloc_lock = NULL; 50 Mutex* JNIGlobalActive_lock = NULL; 51 Mutex* JNIWeakAlloc_lock = NULL; 52 Mutex* JNIWeakActive_lock = NULL; 53 Mutex* StringTableWeakAlloc_lock = NULL; 54 Mutex* StringTableWeakActive_lock = NULL; 55 Mutex* JNIHandleBlockFreeList_lock = NULL; 56 Mutex* VMWeakAlloc_lock = NULL; 57 Mutex* VMWeakActive_lock = NULL; 58 Mutex* ResolvedMethodTableWeakAlloc_lock = NULL; 59 Mutex* ResolvedMethodTableWeakActive_lock = NULL; 60 Mutex* JmethodIdCreation_lock = NULL; 61 Mutex* JfieldIdCreation_lock = NULL; 62 Monitor* JNICritical_lock = NULL; 63 Mutex* JvmtiThreadState_lock = NULL; 64 Monitor* Heap_lock = NULL; 65 Mutex* ExpandHeap_lock = NULL; 66 Mutex* AdapterHandlerLibrary_lock = NULL; 67 Mutex* SignatureHandlerLibrary_lock = NULL; 68 Mutex* VtableStubs_lock = NULL; 69 Mutex* SymbolArena_lock = NULL; 70 Monitor* StringDedupQueue_lock = NULL; 71 Mutex* StringDedupTable_lock = NULL; 72 Monitor* CodeCache_lock = NULL; 73 Mutex* MethodData_lock = NULL; 74 Mutex* TouchedMethodLog_lock = NULL; 75 Mutex* RetData_lock = NULL; 76 Monitor* VMOperationQueue_lock = NULL; 77 Monitor* VMOperationRequest_lock = NULL; 78 Monitor* SerializePage_lock = NULL; 79 Monitor* Threads_lock = NULL; 80 Mutex* NonJavaThreadsList_lock = NULL; 81 Mutex* NonJavaThreadsListSync_lock = NULL; 82 Monitor* CGC_lock = NULL; 83 Monitor* STS_lock = NULL; 84 Monitor* FullGCCount_lock = NULL; 85 Monitor* SATB_Q_CBL_mon = NULL; 86 Monitor* DirtyCardQ_CBL_mon = NULL; 87 Mutex* Shared_DirtyCardQ_lock = NULL; 88 Mutex* MarkStackFreeList_lock = NULL; 89 Mutex* MarkStackChunkList_lock = NULL; 90 Mutex* MonitoringSupport_lock = NULL; 91 Mutex* ParGCRareEvent_lock = NULL; 92 Monitor* CGCPhaseManager_lock = NULL; 93 Mutex* Compile_lock = NULL; 94 Monitor* MethodCompileQueue_lock = NULL; 95 Monitor* CompileThread_lock = NULL; 96 Monitor* Compilation_lock = NULL; 97 Mutex* CompileTaskAlloc_lock = NULL; 98 Mutex* CompileStatistics_lock = NULL; 99 Mutex* DirectivesStack_lock = NULL; 100 Mutex* MultiArray_lock = NULL; 101 Monitor* Terminator_lock = NULL; 102 Monitor* InitCompleted_lock = NULL; 103 Monitor* BeforeExit_lock = NULL; 104 Monitor* Notify_lock = NULL; 105 Mutex* ProfilePrint_lock = NULL; 106 Mutex* ExceptionCache_lock = NULL; 107 Mutex* OsrList_lock = NULL; 108 Mutex* NMethodSweeperStats_lock = NULL; 109 #ifndef PRODUCT 110 Mutex* FullGCALot_lock = NULL; 111 #endif 112 113 Mutex* Debug1_lock = NULL; 114 Mutex* Debug2_lock = NULL; 115 Mutex* Debug3_lock = NULL; 116 117 Mutex* tty_lock = NULL; 118 119 Mutex* RawMonitor_lock = NULL; 120 Mutex* PerfDataMemAlloc_lock = NULL; 121 Mutex* PerfDataManager_lock = NULL; 122 Mutex* OopMapCacheAlloc_lock = NULL; 123 124 Mutex* FreeList_lock = NULL; 125 Mutex* OldSets_lock = NULL; 126 Monitor* RootRegionScan_lock = NULL; 127 128 Monitor* GCTaskManager_lock = NULL; 129 130 Mutex* Management_lock = NULL; 131 Monitor* Service_lock = NULL; 132 Monitor* PeriodicTask_lock = NULL; 133 Monitor* RedefineClasses_lock = NULL; 134 135 #if INCLUDE_JFR 136 Mutex* JfrStacktrace_lock = NULL; 137 Monitor* JfrMsg_lock = NULL; 138 Mutex* JfrBuffer_lock = NULL; 139 Mutex* JfrStream_lock = NULL; 140 Monitor* JfrThreadSampler_lock = NULL; 141 #endif 142 143 #ifndef SUPPORTS_NATIVE_CX8 144 Mutex* UnsafeJlong_lock = NULL; 145 #endif 146 Monitor* CodeHeapStateAnalytics_lock = NULL; 147 148 Mutex* MetaspaceExpand_lock = NULL; 149 Mutex* ClassLoaderDataGraph_lock = NULL; 150 Monitor* ThreadsSMRDelete_lock = NULL; 151 Mutex* SharedDecoder_lock = NULL; 152 Mutex* DCmdFactory_lock = NULL; 153 #if INCLUDE_NMT 154 Mutex* NMTQuery_lock = NULL; 155 #endif 156 #if INCLUDE_CDS 157 #if INCLUDE_JVMTI 158 Mutex* CDSClassFileStream_lock = NULL; 159 #endif 160 Mutex* DumpTimeTable_lock = NULL; 161 #endif // INCLUDE_CDS 162 163 #if INCLUDE_JVMCI 164 Monitor* JVMCI_lock = NULL; 165 Mutex* JVMCIGlobalAlloc_lock = NULL; 166 Mutex* JVMCIGlobalActive_lock = NULL; 167 #endif 168 169 170 #define MAX_NUM_MUTEX 128 171 static Monitor * _mutex_array[MAX_NUM_MUTEX]; 172 static int _num_mutex; 173 174 #ifdef ASSERT 175 void assert_locked_or_safepoint(const Monitor * lock) { 176 // check if this thread owns the lock (common case) 177 if (IgnoreLockingAssertions) return; 178 assert(lock != NULL, "Need non-NULL lock"); 179 if (lock->owned_by_self()) return; 180 if (SafepointSynchronize::is_at_safepoint()) return; 181 if (!Universe::is_fully_initialized()) return; 182 // see if invoker of VM operation owns it 183 VM_Operation* op = VMThread::vm_operation(); 184 if (op != NULL && op->calling_thread() == lock->owner()) return; 185 fatal("must own lock %s", lock->name()); 186 } 187 188 // a weaker assertion than the above 189 void assert_locked_or_safepoint_weak(const Monitor * lock) { 190 if (IgnoreLockingAssertions) return; 191 assert(lock != NULL, "Need non-NULL lock"); 192 if (lock->is_locked()) return; 193 if (SafepointSynchronize::is_at_safepoint()) return; 194 if (!Universe::is_fully_initialized()) return; 195 fatal("must own lock %s", lock->name()); 196 } 197 198 // a stronger assertion than the above 199 void assert_lock_strong(const Monitor * lock) { 200 if (IgnoreLockingAssertions) return; 201 assert(lock != NULL, "Need non-NULL lock"); 202 if (lock->owned_by_self()) return; 203 fatal("must own lock %s", lock->name()); 204 } 205 #endif 206 207 #define def(var, type, pri, vm_block, safepoint_check_allowed ) { \ 208 var = new type(Mutex::pri, #var, vm_block, safepoint_check_allowed); \ 209 assert(_num_mutex < MAX_NUM_MUTEX, "increase MAX_NUM_MUTEX"); \ 210 _mutex_array[_num_mutex++] = var; \ 211 } 212 213 // Using Padded subclasses to prevent false sharing of these global monitors and mutexes. 214 void mutex_init() { 215 def(tty_lock , PaddedMutex , tty, true, Monitor::_safepoint_check_never); // allow to lock in VM 216 217 def(CGC_lock , PaddedMonitor, special, true, Monitor::_safepoint_check_never); // coordinate between fore- and background GC 218 def(STS_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never); 219 220 def(VMWeakAlloc_lock , PaddedMutex , vmweak, true, Monitor::_safepoint_check_never); 221 def(VMWeakActive_lock , PaddedMutex , vmweak-1, true, Monitor::_safepoint_check_never); 222 223 def(StringTableWeakAlloc_lock , PaddedMutex , vmweak, true, Monitor::_safepoint_check_never); 224 def(StringTableWeakActive_lock , PaddedMutex , vmweak-1, true, Monitor::_safepoint_check_never); 225 226 def(ResolvedMethodTableWeakAlloc_lock , PaddedMutex , vmweak, true, Monitor::_safepoint_check_never); 227 def(ResolvedMethodTableWeakActive_lock , PaddedMutex , vmweak-1, true, Monitor::_safepoint_check_never); 228 229 def(FullGCCount_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never); // in support of ExplicitGCInvokesConcurrent 230 if (UseG1GC) { 231 def(SATB_Q_CBL_mon , PaddedMonitor, access, true, Monitor::_safepoint_check_never); 232 233 def(DirtyCardQ_CBL_mon , PaddedMonitor, access, true, Monitor::_safepoint_check_never); 234 def(Shared_DirtyCardQ_lock , PaddedMutex , access + 1, true, Monitor::_safepoint_check_never); 235 236 def(FreeList_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never); 237 def(OldSets_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never); 238 def(RootRegionScan_lock , PaddedMonitor, leaf , true, Monitor::_safepoint_check_never); 239 240 def(StringDedupQueue_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never); 241 def(StringDedupTable_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 242 243 def(MarkStackFreeList_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never); 244 def(MarkStackChunkList_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never); 245 246 def(MonitoringSupport_lock , PaddedMutex , native , true, Monitor::_safepoint_check_never); // used for serviceability monitoring support 247 } 248 if (UseShenandoahGC) { 249 def(SATB_Q_CBL_mon , PaddedMonitor, access, true, Monitor::_safepoint_check_never); 250 251 def(StringDedupQueue_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never); 252 def(StringDedupTable_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 253 } 254 def(ParGCRareEvent_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_always); 255 def(CGCPhaseManager_lock , PaddedMonitor, leaf, false, Monitor::_safepoint_check_always); 256 def(CodeCache_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); 257 def(RawMonitor_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); 258 def(OopMapCacheAlloc_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for oop_map_cache allocation. 259 260 def(MetaspaceExpand_lock , PaddedMutex , leaf-1, true, Monitor::_safepoint_check_never); 261 def(ClassLoaderDataGraph_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_always); 262 263 def(Patching_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); // used for safepointing and code patching. 264 def(Service_lock , PaddedMonitor, special, true, Monitor::_safepoint_check_never); // used for service thread operations 265 def(JmethodIdCreation_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for creating jmethodIDs. 266 267 def(SystemDictionary_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_always); 268 def(ProtectionDomainSet_lock , PaddedMutex , leaf-1, true, Monitor::_safepoint_check_never); 269 def(SharedDictionary_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); 270 def(Module_lock , PaddedMutex , leaf+2, true, Monitor::_safepoint_check_always); 271 def(InlineCacheBuffer_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 272 def(VMStatistic_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); 273 def(ExpandHeap_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // Used during compilation by VM thread 274 def(JNIHandleBlockFreeList_lock , PaddedMutex , leaf-1, true, Monitor::_safepoint_check_never); // handles are used by VM thread 275 def(SignatureHandlerLibrary_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); 276 def(SymbolArena_lock , PaddedMutex , leaf+2, true, Monitor::_safepoint_check_never); 277 def(ProfilePrint_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); // serial profile printing 278 def(ExceptionCache_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); // serial profile printing 279 def(OsrList_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 280 def(Debug1_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 281 #ifndef PRODUCT 282 def(FullGCALot_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); // a lock to make FullGCALot MT safe 283 #endif 284 def(BeforeExit_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_always); 285 def(PerfDataMemAlloc_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for allocating PerfData memory for performance data 286 def(PerfDataManager_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for synchronized access to PerfDataManager resources 287 288 // CMS_modUnionTable_lock leaf 289 // CMS_bitMap_lock leaf 1 290 // CMS_freeList_lock leaf 2 291 292 def(Threads_lock , PaddedMonitor, barrier, true, Monitor::_safepoint_check_sometimes); // Used for safepoint protocol. 293 def(NonJavaThreadsList_lock , PaddedMutex, leaf, true, Monitor::_safepoint_check_never); 294 def(NonJavaThreadsListSync_lock , PaddedMutex, leaf, true, Monitor::_safepoint_check_never); 295 296 def(VMOperationQueue_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_never); // VM_thread allowed to block on these 297 def(VMOperationRequest_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_always); 298 def(RetData_lock , PaddedMutex , nonleaf, false, Monitor::_safepoint_check_always); 299 def(Terminator_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_always); 300 def(InitCompleted_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never); 301 def(VtableStubs_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_never); 302 def(Notify_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_always); 303 def(JNIGlobalAlloc_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_never); 304 def(JNIGlobalActive_lock , PaddedMutex , nonleaf-1, true, Monitor::_safepoint_check_never); 305 def(JNIWeakAlloc_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_never); 306 def(JNIWeakActive_lock , PaddedMutex , nonleaf-1, true, Monitor::_safepoint_check_never); 307 def(JNICritical_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_always); // used for JNI critical regions 308 def(AdapterHandlerLibrary_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_always); 309 310 def(Heap_lock , PaddedMonitor, nonleaf+1, false, Monitor::_safepoint_check_sometimes); // Doesn't safepoint check during termination. 311 def(JfieldIdCreation_lock , PaddedMutex , nonleaf+1, true, Monitor::_safepoint_check_always); // jfieldID, Used in VM_Operation 312 313 def(CompiledIC_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_never); // locks VtableStubs_lock, InlineCacheBuffer_lock 314 def(CompileTaskAlloc_lock , PaddedMutex , nonleaf+2, true, Monitor::_safepoint_check_always); 315 def(CompileStatistics_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); 316 def(DirectivesStack_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); 317 def(MultiArray_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); 318 319 def(JvmtiThreadState_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); // Used by JvmtiThreadState/JvmtiEventController 320 def(Management_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); // used for JVM management 321 322 def(Compile_lock , PaddedMutex , nonleaf+3, true, Monitor::_safepoint_check_always); 323 def(MethodData_lock , PaddedMutex , nonleaf+3, false, Monitor::_safepoint_check_always); 324 def(TouchedMethodLog_lock , PaddedMutex , nonleaf+3, false, Monitor::_safepoint_check_always); 325 326 def(MethodCompileQueue_lock , PaddedMonitor, nonleaf+4, true, Monitor::_safepoint_check_always); 327 def(Debug2_lock , PaddedMutex , nonleaf+4, true, Monitor::_safepoint_check_never); 328 def(Debug3_lock , PaddedMutex , nonleaf+4, true, Monitor::_safepoint_check_never); 329 def(CompileThread_lock , PaddedMonitor, nonleaf+5, false, Monitor::_safepoint_check_always); 330 def(PeriodicTask_lock , PaddedMonitor, nonleaf+5, true, Monitor::_safepoint_check_always); 331 def(RedefineClasses_lock , PaddedMonitor, nonleaf+5, true, Monitor::_safepoint_check_always); 332 333 if (WhiteBoxAPI) { 334 def(Compilation_lock , PaddedMonitor, leaf, false, Monitor::_safepoint_check_never); 335 } 336 337 #if INCLUDE_JFR 338 def(JfrMsg_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_always); 339 def(JfrBuffer_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 340 def(JfrStream_lock , PaddedMutex , leaf+1, true, Monitor::_safepoint_check_never); // ensure to rank lower than 'safepoint' 341 def(JfrStacktrace_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); 342 def(JfrThreadSampler_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never); 343 #endif 344 345 #ifndef SUPPORTS_NATIVE_CX8 346 def(UnsafeJlong_lock , PaddedMutex , special, false, Monitor::_safepoint_check_never); 347 #endif 348 349 def(CodeHeapStateAnalytics_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 350 def(NMethodSweeperStats_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); 351 def(ThreadsSMRDelete_lock , PaddedMonitor, special, false, Monitor::_safepoint_check_never); 352 def(SharedDecoder_lock , PaddedMutex , native, false, Monitor::_safepoint_check_never); 353 def(DCmdFactory_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 354 #if INCLUDE_NMT 355 def(NMTQuery_lock , PaddedMutex , max_nonleaf, false, Monitor::_safepoint_check_always); 356 #endif 357 #if INCLUDE_CDS 358 #if INCLUDE_JVMTI 359 def(CDSClassFileStream_lock , PaddedMutex , max_nonleaf, false, Monitor::_safepoint_check_always); 360 #endif 361 362 #if INCLUDE_JVMCI 363 def(JVMCI_lock , PaddedMonitor, nonleaf+2, true, Monitor::_safepoint_check_always); 364 def(JVMCIGlobalAlloc_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_never); 365 def(JVMCIGlobalActive_lock , PaddedMutex , nonleaf-1, true, Monitor::_safepoint_check_never); 366 #endif 367 def(DumpTimeTable_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 368 #endif // INCLUDE_CDS 369 } 370 371 GCMutexLocker::GCMutexLocker(Monitor * mutex) { 372 if (SafepointSynchronize::is_at_safepoint()) { 373 _locked = false; 374 } else { 375 _mutex = mutex; 376 _locked = true; 377 _mutex->lock(); 378 } 379 } 380 381 // Print all mutexes/monitors that are currently owned by a thread; called 382 // by fatal error handler. 383 void print_owned_locks_on_error(outputStream* st) { 384 st->print("VM Mutex/Monitor currently owned by a thread: "); 385 bool none = true; 386 for (int i = 0; i < _num_mutex; i++) { 387 // see if it has an owner 388 if (_mutex_array[i]->owner() != NULL) { 389 if (none) { 390 // print format used by Mutex::print_on_error() 391 st->print_cr(" ([mutex/lock_event])"); 392 none = false; 393 } 394 _mutex_array[i]->print_on_error(st); 395 st->cr(); 396 } 397 } 398 if (none) st->print_cr("None"); 399 }