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