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