1 /* 2 * Copyright (c) 1997, 2018, 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 Mutex* StringTable_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* Safepoint_lock = NULL; 77 Monitor* SerializePage_lock = NULL; 78 Monitor* Threads_lock = NULL; 79 Mutex* NonJavaThreadsList_lock = NULL; 80 Monitor* CGC_lock = NULL; 81 Monitor* STS_lock = NULL; 82 Monitor* FullGCCount_lock = NULL; 83 Mutex* SATB_Q_FL_lock = NULL; 84 Monitor* SATB_Q_CBL_mon = NULL; 85 Mutex* Shared_SATB_Q_lock = NULL; 86 Mutex* DirtyCardQ_FL_lock = NULL; 87 Monitor* DirtyCardQ_CBL_mon = NULL; 88 Mutex* Shared_DirtyCardQ_lock = NULL; 89 Mutex* MarkStackFreeList_lock = NULL; 90 Mutex* MarkStackChunkList_lock = NULL; 91 Mutex* ParGCRareEvent_lock = NULL; 92 Mutex* DerivedPointerTableGC_lock = NULL; 93 Monitor* CGCPhaseManager_lock = NULL; 94 Mutex* Compile_lock = NULL; 95 Monitor* MethodCompileQueue_lock = NULL; 96 Monitor* CompileThread_lock = NULL; 97 Monitor* Compilation_lock = NULL; 98 Mutex* CompileTaskAlloc_lock = NULL; 99 Mutex* CompileStatistics_lock = NULL; 100 Mutex* DirectivesStack_lock = NULL; 101 Mutex* MultiArray_lock = NULL; 102 Monitor* Terminator_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; 108 109 #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 Mutex* ThreadHeapSampler_lock = NULL; 136 137 #if INCLUDE_JFR 138 Mutex* JfrStacktrace_lock = NULL; 139 Monitor* JfrMsg_lock = NULL; 140 Mutex* JfrBuffer_lock = NULL; 141 Mutex* JfrStream_lock = NULL; 142 #endif 143 144 #ifndef SUPPORTS_NATIVE_CX8 145 Mutex* UnsafeJlong_lock = NULL; 146 #endif 147 Monitor* CodeHeapStateAnalytics_lock = NULL; 148 149 Mutex* MetaspaceExpand_lock = NULL; 150 Mutex* ClassLoaderDataGraph_lock = NULL; 151 152 #define MAX_NUM_MUTEX 128 153 static Monitor * _mutex_array[MAX_NUM_MUTEX]; 154 static int _num_mutex; 155 156 #ifdef ASSERT 157 void assert_locked_or_safepoint(const Monitor * lock) { 158 // check if this thread owns the lock (common case) 159 if (IgnoreLockingAssertions) return; 160 assert(lock != NULL, "Need non-NULL lock"); 161 if (lock->owned_by_self()) return; 162 if (SafepointSynchronize::is_at_safepoint()) return; 163 if (!Universe::is_fully_initialized()) return; 164 // see if invoker of VM operation owns it 165 VM_Operation* op = VMThread::vm_operation(); 166 if (op != NULL && op->calling_thread() == lock->owner()) return; 167 fatal("must own lock %s", lock->name()); 168 } 169 170 // a stronger assertion than the above 171 void assert_lock_strong(const Monitor * lock) { 172 if (IgnoreLockingAssertions) return; 173 assert(lock != NULL, "Need non-NULL lock"); 174 if (lock->owned_by_self()) return; 175 fatal("must own lock %s", lock->name()); 176 } 177 #endif 178 179 #define def(var, type, pri, vm_block, safepoint_check_allowed ) { \ 180 var = new type(Mutex::pri, #var, vm_block, safepoint_check_allowed); \ 181 assert(_num_mutex < MAX_NUM_MUTEX, "increase MAX_NUM_MUTEX"); \ 182 _mutex_array[_num_mutex++] = var; \ 183 } 184 185 // Using Padded subclasses to prevent false sharing of these global monitors and mutexes. 186 void mutex_init() { 187 def(tty_lock , PaddedMutex , event, true, Monitor::_safepoint_check_never); // allow to lock in VM 188 189 def(CGC_lock , PaddedMonitor, special, true, Monitor::_safepoint_check_never); // coordinate between fore- and background GC 190 def(STS_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never); 191 192 def(VMWeakAlloc_lock , PaddedMutex , vmweak, true, Monitor::_safepoint_check_never); 193 def(VMWeakActive_lock , PaddedMutex , vmweak-1, true, Monitor::_safepoint_check_never); 194 195 def(StringTableWeakAlloc_lock , PaddedMutex , vmweak, true, Monitor::_safepoint_check_never); 196 def(StringTableWeakActive_lock , PaddedMutex , vmweak-1, true, Monitor::_safepoint_check_never); 197 198 if (UseConcMarkSweepGC || UseG1GC) { 199 def(FullGCCount_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never); // in support of ExplicitGCInvokesConcurrent 200 } 201 if (UseG1GC) { 202 def(SATB_Q_FL_lock , PaddedMutex , access, true, Monitor::_safepoint_check_never); 203 def(SATB_Q_CBL_mon , PaddedMonitor, access, true, Monitor::_safepoint_check_never); 204 def(Shared_SATB_Q_lock , PaddedMutex , access + 1, true, Monitor::_safepoint_check_never); 205 206 def(DirtyCardQ_FL_lock , PaddedMutex , access, true, Monitor::_safepoint_check_never); 207 def(DirtyCardQ_CBL_mon , PaddedMonitor, access, true, Monitor::_safepoint_check_never); 208 def(Shared_DirtyCardQ_lock , PaddedMutex , access + 1, true, Monitor::_safepoint_check_never); 209 210 def(FreeList_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never); 211 def(OldSets_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never); 212 def(RootRegionScan_lock , PaddedMonitor, leaf , true, Monitor::_safepoint_check_never); 213 214 def(StringDedupQueue_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never); 215 def(StringDedupTable_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 216 217 def(MarkStackFreeList_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never); 218 def(MarkStackChunkList_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never); 219 } 220 def(ParGCRareEvent_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_sometimes); 221 def(DerivedPointerTableGC_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 222 def(CGCPhaseManager_lock , PaddedMonitor, leaf, false, Monitor::_safepoint_check_sometimes); 223 def(CodeCache_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); 224 def(RawMonitor_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); 225 def(OopMapCacheAlloc_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for oop_map_cache allocation. 226 227 def(MetaspaceExpand_lock , PaddedMutex , leaf-1, true, Monitor::_safepoint_check_never); 228 def(ClassLoaderDataGraph_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_always); 229 230 def(Patching_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); // used for safepointing and code patching. 231 def(Service_lock , PaddedMonitor, special, true, Monitor::_safepoint_check_never); // used for service thread operations 232 def(JmethodIdCreation_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for creating jmethodIDs. 233 234 def(SystemDictionary_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_always); // lookups done by VM thread 235 def(SharedDictionary_lock , PaddedMutex, leaf, true, Monitor::_safepoint_check_always); // lookups done by VM thread 236 def(Module_lock , PaddedMutex , leaf+2, true, Monitor::_safepoint_check_always); 237 def(InlineCacheBuffer_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); 238 def(VMStatistic_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); 239 def(ExpandHeap_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // Used during compilation by VM thread 240 def(JNIHandleBlockFreeList_lock , PaddedMutex , leaf-1, true, Monitor::_safepoint_check_never); // handles are used by VM thread 241 def(SignatureHandlerLibrary_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); 242 def(SymbolArena_lock , PaddedMutex , leaf+2, true, Monitor::_safepoint_check_never); 243 def(StringTable_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); 244 def(ProfilePrint_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); // serial profile printing 245 def(ExceptionCache_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); // serial profile printing 246 def(OsrList_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 247 def(Debug1_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 248 #ifndef PRODUCT 249 def(FullGCALot_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); // a lock to make FullGCALot MT safe 250 #endif 251 def(BeforeExit_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_always); 252 def(PerfDataMemAlloc_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for allocating PerfData memory for performance data 253 def(PerfDataManager_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for synchronized access to PerfDataManager resources 254 255 // CMS_modUnionTable_lock leaf 256 // CMS_bitMap_lock leaf 1 257 // CMS_freeList_lock leaf 2 258 259 def(Safepoint_lock , PaddedMonitor, safepoint, true, Monitor::_safepoint_check_sometimes); // locks SnippetCache_lock/Threads_lock 260 261 def(Threads_lock , PaddedMonitor, barrier, true, Monitor::_safepoint_check_sometimes); 262 def(NonJavaThreadsList_lock , PaddedMutex, leaf, true, Monitor::_safepoint_check_never); 263 264 def(VMOperationQueue_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_sometimes); // VM_thread allowed to block on these 265 def(VMOperationRequest_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_sometimes); 266 def(RetData_lock , PaddedMutex , nonleaf, false, Monitor::_safepoint_check_always); 267 def(Terminator_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_sometimes); 268 def(VtableStubs_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_always); 269 def(Notify_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_always); 270 def(JNIGlobalAlloc_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_never); 271 def(JNIGlobalActive_lock , PaddedMutex , nonleaf-1, true, Monitor::_safepoint_check_never); 272 def(JNIWeakAlloc_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_never); 273 def(JNIWeakActive_lock , PaddedMutex , nonleaf-1, true, Monitor::_safepoint_check_never); 274 def(JNICritical_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_always); // used for JNI critical regions 275 def(AdapterHandlerLibrary_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_always); 276 277 def(Heap_lock , PaddedMonitor, nonleaf+1, false, Monitor::_safepoint_check_sometimes); 278 def(JfieldIdCreation_lock , PaddedMutex , nonleaf+1, true, Monitor::_safepoint_check_always); // jfieldID, Used in VM_Operation 279 def(ResolvedMethodTable_lock , PaddedMutex , nonleaf+1, false, Monitor::_safepoint_check_always); // Used to protect ResolvedMethodTable 280 281 def(CompiledIC_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); // locks VtableStubs_lock, InlineCacheBuffer_lock 282 def(CompileTaskAlloc_lock , PaddedMutex , nonleaf+2, true, Monitor::_safepoint_check_always); 283 def(CompileStatistics_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); 284 def(DirectivesStack_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); 285 def(MultiArray_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); 286 287 def(JvmtiThreadState_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); // Used by JvmtiThreadState/JvmtiEventController 288 def(Management_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); // used for JVM management 289 290 def(Compile_lock , PaddedMutex , nonleaf+3, true, Monitor::_safepoint_check_sometimes); 291 def(MethodData_lock , PaddedMutex , nonleaf+3, false, Monitor::_safepoint_check_always); 292 def(TouchedMethodLog_lock , PaddedMutex , nonleaf+3, false, Monitor::_safepoint_check_always); 293 294 def(MethodCompileQueue_lock , PaddedMonitor, nonleaf+4, true, Monitor::_safepoint_check_always); 295 def(Debug2_lock , PaddedMutex , nonleaf+4, true, Monitor::_safepoint_check_never); 296 def(Debug3_lock , PaddedMutex , nonleaf+4, true, Monitor::_safepoint_check_never); 297 def(CompileThread_lock , PaddedMonitor, nonleaf+5, false, Monitor::_safepoint_check_always); 298 def(PeriodicTask_lock , PaddedMonitor, nonleaf+5, true, Monitor::_safepoint_check_sometimes); 299 def(RedefineClasses_lock , PaddedMonitor, nonleaf+5, true, Monitor::_safepoint_check_always); 300 301 def(ThreadHeapSampler_lock , PaddedMutex, nonleaf, false, Monitor::_safepoint_check_never); 302 303 if (WhiteBoxAPI) { 304 def(Compilation_lock , PaddedMonitor, leaf, false, Monitor::_safepoint_check_never); 305 } 306 307 #if INCLUDE_JFR 308 def(JfrMsg_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_always); 309 def(JfrBuffer_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 310 def(JfrStream_lock , PaddedMutex , leaf+1, true, Monitor::_safepoint_check_never); // ensure to rank lower than 'safepoint' 311 def(JfrStacktrace_lock , PaddedMutex , special, true, Monitor::_safepoint_check_sometimes); 312 #endif 313 314 #ifndef SUPPORTS_NATIVE_CX8 315 def(UnsafeJlong_lock , PaddedMutex , special, false, Monitor::_safepoint_check_never); 316 #endif 317 318 def(CodeHeapStateAnalytics_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 319 } 320 321 GCMutexLocker::GCMutexLocker(Monitor * mutex) { 322 if (SafepointSynchronize::is_at_safepoint()) { 323 _locked = false; 324 } else { 325 _mutex = mutex; 326 _locked = true; 327 _mutex->lock(); 328 } 329 } 330 331 // Print all mutexes/monitors that are currently owned by a thread; called 332 // by fatal error handler. 333 void print_owned_locks_on_error(outputStream* st) { 334 st->print("VM Mutex/Monitor currently owned by a thread: "); 335 bool none = true; 336 for (int i = 0; i < _num_mutex; i++) { 337 // see if it has an owner 338 if (_mutex_array[i]->owner() != NULL) { 339 if (none) { 340 // print format used by Mutex::print_on_error() 341 st->print_cr(" ([mutex/lock_event])"); 342 none = false; 343 } 344 _mutex_array[i]->print_on_error(st); 345 st->cr(); 346 } 347 } 348 if (none) st->print_cr("None"); 349 }