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