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