1 /* 2 * Copyright (c) 1997, 2016, 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* JNIGlobalHandle_lock = NULL; 47 Mutex* JNIHandleBlockFreeList_lock = NULL; 48 Mutex* MemberNameTable_lock = NULL; 49 Mutex* JmethodIdCreation_lock = NULL; 50 Mutex* JfieldIdCreation_lock = NULL; 51 Monitor* JNICritical_lock = NULL; 52 Mutex* JvmtiThreadState_lock = NULL; 53 Monitor* Heap_lock = NULL; 54 Mutex* ExpandHeap_lock = NULL; 55 Mutex* AdapterHandlerLibrary_lock = NULL; 56 Mutex* SignatureHandlerLibrary_lock = NULL; 57 Mutex* VtableStubs_lock = NULL; 58 Mutex* SymbolTable_lock = NULL; 59 Mutex* StringTable_lock = NULL; 60 Monitor* StringDedupQueue_lock = NULL; 61 Mutex* StringDedupTable_lock = NULL; 62 Monitor* CodeCache_lock = NULL; 63 Mutex* MethodData_lock = NULL; 64 Mutex* TouchedMethodLog_lock = NULL; 65 Mutex* RetData_lock = NULL; 66 Monitor* VMOperationQueue_lock = NULL; 67 Monitor* VMOperationRequest_lock = NULL; 68 Monitor* Safepoint_lock = NULL; 69 Monitor* SerializePage_lock = NULL; 70 Monitor* Threads_lock = NULL; 71 Monitor* CGC_lock = NULL; 72 Monitor* STS_lock = NULL; 73 Monitor* FullGCCount_lock = NULL; 74 Mutex* SATB_Q_FL_lock = NULL; 75 Monitor* SATB_Q_CBL_mon = NULL; 76 Mutex* Shared_SATB_Q_lock = NULL; 77 Mutex* DirtyCardQ_FL_lock = NULL; 78 Monitor* DirtyCardQ_CBL_mon = NULL; 79 Mutex* Shared_DirtyCardQ_lock = NULL; 80 Mutex* MarkStackFreeList_lock = NULL; 81 Mutex* MarkStackChunkList_lock = NULL; 82 Mutex* ParGCRareEvent_lock = NULL; 83 Mutex* DerivedPointerTableGC_lock = NULL; 84 Mutex* Compile_lock = NULL; 85 Monitor* MethodCompileQueue_lock = NULL; 86 Monitor* CompileThread_lock = NULL; 87 Monitor* Compilation_lock = NULL; 88 Mutex* CompileTaskAlloc_lock = NULL; 89 Mutex* CompileStatistics_lock = NULL; 90 Mutex* DirectivesStack_lock = NULL; 91 Mutex* MultiArray_lock = NULL; 92 Monitor* Terminator_lock = NULL; 93 Monitor* BeforeExit_lock = NULL; 94 Monitor* Notify_lock = NULL; 95 Mutex* ProfilePrint_lock = NULL; 96 Mutex* ExceptionCache_lock = NULL; 97 Mutex* OsrList_lock = NULL; 98 99 #ifndef PRODUCT 100 Mutex* FullGCALot_lock = NULL; 101 #endif 102 103 Mutex* Debug1_lock = NULL; 104 Mutex* Debug2_lock = NULL; 105 Mutex* Debug3_lock = NULL; 106 107 Mutex* tty_lock = NULL; 108 109 Mutex* RawMonitor_lock = NULL; 110 Mutex* PerfDataMemAlloc_lock = NULL; 111 Mutex* PerfDataManager_lock = NULL; 112 Mutex* OopMapCacheAlloc_lock = NULL; 113 114 Mutex* FreeList_lock = NULL; 115 Monitor* SecondaryFreeList_lock = NULL; 116 Mutex* OldSets_lock = NULL; 117 Monitor* RootRegionScan_lock = NULL; 118 Mutex* MMUTracker_lock = NULL; 119 120 Monitor* GCTaskManager_lock = NULL; 121 122 Mutex* Management_lock = NULL; 123 Monitor* Service_lock = NULL; 124 Monitor* PeriodicTask_lock = NULL; 125 Monitor* RedefineClasses_lock = NULL; 126 127 #ifdef INCLUDE_TRACE 128 Mutex* JfrStacktrace_lock = NULL; 129 Monitor* JfrMsg_lock = NULL; 130 Mutex* JfrBuffer_lock = NULL; 131 Mutex* JfrStream_lock = NULL; 132 Mutex* JfrThreadGroups_lock = NULL; 133 #endif 134 135 #ifndef SUPPORTS_NATIVE_CX8 136 Mutex* UnsafeJlong_lock = NULL; 137 #endif 138 139 #define MAX_NUM_MUTEX 128 140 static Monitor * _mutex_array[MAX_NUM_MUTEX]; 141 static int _num_mutex; 142 143 #ifdef ASSERT 144 void assert_locked_or_safepoint(const Monitor * lock) { 145 // check if this thread owns the lock (common case) 146 if (IgnoreLockingAssertions) return; 147 assert(lock != NULL, "Need non-NULL lock"); 148 if (lock->owned_by_self()) return; 149 if (SafepointSynchronize::is_at_safepoint()) return; 150 if (!Universe::is_fully_initialized()) return; 151 // see if invoker of VM operation owns it 152 VM_Operation* op = VMThread::vm_operation(); 153 if (op != NULL && op->calling_thread() == lock->owner()) return; 154 fatal("must own lock %s", lock->name()); 155 } 156 157 // a stronger assertion than the above 158 void assert_lock_strong(const Monitor * lock) { 159 if (IgnoreLockingAssertions) return; 160 assert(lock != NULL, "Need non-NULL lock"); 161 if (lock->owned_by_self()) return; 162 fatal("must own lock %s", lock->name()); 163 } 164 #endif 165 166 #define def(var, type, pri, vm_block, safepoint_check_allowed ) { \ 167 var = new type(Mutex::pri, #var, vm_block, safepoint_check_allowed); \ 168 assert(_num_mutex < MAX_NUM_MUTEX, "increase MAX_NUM_MUTEX"); \ 169 _mutex_array[_num_mutex++] = var; \ 170 } 171 172 // Using Padded subclasses to prevent false sharing of these global monitors and mutexes. 173 void mutex_init() { 174 def(tty_lock , PaddedMutex , event, true, Monitor::_safepoint_check_never); // allow to lock in VM 175 176 def(CGC_lock , PaddedMonitor, special, true, Monitor::_safepoint_check_never); // coordinate between fore- and background GC 177 def(STS_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never); 178 179 if (UseConcMarkSweepGC || UseG1GC) { 180 def(FullGCCount_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never); // in support of ExplicitGCInvokesConcurrent 181 } 182 if (UseG1GC) { 183 184 def(SATB_Q_FL_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); 185 def(SATB_Q_CBL_mon , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_never); 186 def(Shared_SATB_Q_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_never); 187 188 def(DirtyCardQ_FL_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); 189 def(DirtyCardQ_CBL_mon , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_never); 190 def(Shared_DirtyCardQ_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_never); 191 192 def(FreeList_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never); 193 def(SecondaryFreeList_lock , PaddedMonitor, leaf , true, Monitor::_safepoint_check_never); 194 def(OldSets_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never); 195 def(RootRegionScan_lock , PaddedMonitor, leaf , true, Monitor::_safepoint_check_never); 196 def(MMUTracker_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never); 197 198 def(StringDedupQueue_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never); 199 def(StringDedupTable_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 200 201 def(MarkStackFreeList_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never); 202 def(MarkStackChunkList_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never); 203 } 204 def(ParGCRareEvent_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_sometimes); 205 def(DerivedPointerTableGC_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 206 def(CodeCache_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); 207 def(RawMonitor_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); 208 def(OopMapCacheAlloc_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for oop_map_cache allocation. 209 210 def(Patching_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); // used for safepointing and code patching. 211 def(Service_lock , PaddedMonitor, special, true, Monitor::_safepoint_check_never); // used for service thread operations 212 def(JmethodIdCreation_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for creating jmethodIDs. 213 214 def(SystemDictionary_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_always); // lookups done by VM thread 215 def(Module_lock , PaddedMutex , leaf+2, true, Monitor::_safepoint_check_always); 216 def(InlineCacheBuffer_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); 217 def(VMStatistic_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); 218 def(ExpandHeap_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // Used during compilation by VM thread 219 def(JNIHandleBlockFreeList_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); // handles are used by VM thread 220 def(SignatureHandlerLibrary_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); 221 def(SymbolTable_lock , PaddedMutex , leaf+2, true, Monitor::_safepoint_check_always); 222 def(StringTable_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); 223 def(ProfilePrint_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); // serial profile printing 224 def(ExceptionCache_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); // serial profile printing 225 def(OsrList_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 226 def(Debug1_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 227 #ifndef PRODUCT 228 def(FullGCALot_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); // a lock to make FullGCALot MT safe 229 #endif 230 def(BeforeExit_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_always); 231 def(PerfDataMemAlloc_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for allocating PerfData memory for performance data 232 def(PerfDataManager_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for synchronized access to PerfDataManager resources 233 234 // CMS_modUnionTable_lock leaf 235 // CMS_bitMap_lock leaf 1 236 // CMS_freeList_lock leaf 2 237 238 def(Safepoint_lock , PaddedMonitor, safepoint, true, Monitor::_safepoint_check_sometimes); // locks SnippetCache_lock/Threads_lock 239 240 def(Threads_lock , PaddedMonitor, barrier, true, Monitor::_safepoint_check_sometimes); 241 242 def(VMOperationQueue_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_sometimes); // VM_thread allowed to block on these 243 def(VMOperationRequest_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_sometimes); 244 def(RetData_lock , PaddedMutex , nonleaf, false, Monitor::_safepoint_check_always); 245 def(Terminator_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_sometimes); 246 def(VtableStubs_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_always); 247 def(Notify_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_always); 248 def(JNIGlobalHandle_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_always); // locks JNIHandleBlockFreeList_lock 249 def(JNICritical_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_always); // used for JNI critical regions 250 def(AdapterHandlerLibrary_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_always); 251 252 def(Heap_lock , PaddedMonitor, nonleaf+1, false, Monitor::_safepoint_check_sometimes); 253 def(JfieldIdCreation_lock , PaddedMutex , nonleaf+1, true, Monitor::_safepoint_check_always); // jfieldID, Used in VM_Operation 254 def(MemberNameTable_lock , PaddedMutex , nonleaf+1, false, Monitor::_safepoint_check_always); // Used to protect MemberNameTable 255 256 def(CompiledIC_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); // locks VtableStubs_lock, InlineCacheBuffer_lock 257 def(CompileTaskAlloc_lock , PaddedMutex , nonleaf+2, true, Monitor::_safepoint_check_always); 258 def(CompileStatistics_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); 259 def(DirectivesStack_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); 260 def(MultiArray_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); // locks SymbolTable_lock 261 262 def(JvmtiThreadState_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); // Used by JvmtiThreadState/JvmtiEventController 263 def(Management_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); // used for JVM management 264 265 def(Compile_lock , PaddedMutex , nonleaf+3, true, Monitor::_safepoint_check_sometimes); 266 def(MethodData_lock , PaddedMutex , nonleaf+3, false, Monitor::_safepoint_check_always); 267 def(TouchedMethodLog_lock , PaddedMutex , nonleaf+3, false, Monitor::_safepoint_check_always); 268 269 def(MethodCompileQueue_lock , PaddedMonitor, nonleaf+4, true, Monitor::_safepoint_check_always); 270 def(Debug2_lock , PaddedMutex , nonleaf+4, true, Monitor::_safepoint_check_never); 271 def(Debug3_lock , PaddedMutex , nonleaf+4, true, Monitor::_safepoint_check_never); 272 def(CompileThread_lock , PaddedMonitor, nonleaf+5, false, Monitor::_safepoint_check_always); 273 def(PeriodicTask_lock , PaddedMonitor, nonleaf+5, true, Monitor::_safepoint_check_sometimes); 274 def(RedefineClasses_lock , PaddedMonitor, nonleaf+5, true, Monitor::_safepoint_check_always); 275 if (WhiteBoxAPI) { 276 def(Compilation_lock , PaddedMonitor, leaf, false, Monitor::_safepoint_check_never); 277 } 278 279 #ifdef INCLUDE_TRACE 280 def(JfrMsg_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_always); 281 def(JfrBuffer_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); 282 def(JfrThreadGroups_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); 283 def(JfrStream_lock , PaddedMutex , leaf+1, true, Monitor::_safepoint_check_never); // ensure to rank lower than 'safepoint' 284 def(JfrStacktrace_lock , PaddedMutex , special, true, Monitor::_safepoint_check_sometimes); 285 #endif 286 287 #ifndef SUPPORTS_NATIVE_CX8 288 def(UnsafeJlong_lock , PaddedMutex , special, false, Monitor::_safepoint_check_never); 289 #endif 290 } 291 292 GCMutexLocker::GCMutexLocker(Monitor * mutex) { 293 if (SafepointSynchronize::is_at_safepoint()) { 294 _locked = false; 295 } else { 296 _mutex = mutex; 297 _locked = true; 298 _mutex->lock(); 299 } 300 } 301 302 // Print all mutexes/monitors that are currently owned by a thread; called 303 // by fatal error handler. 304 void print_owned_locks_on_error(outputStream* st) { 305 st->print("VM Mutex/Monitor currently owned by a thread: "); 306 bool none = true; 307 for (int i = 0; i < _num_mutex; i++) { 308 // see if it has an owner 309 if (_mutex_array[i]->owner() != NULL) { 310 if (none) { 311 // print format used by Mutex::print_on_error() 312 st->print_cr(" ([mutex/lock_event])"); 313 none = false; 314 } 315 _mutex_array[i]->print_on_error(st); 316 st->cr(); 317 } 318 } 319 if (none) st->print_cr("None"); 320 }