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