1 /* 2 * Copyright (c) 1997, 2014, 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 #ifndef SHARE_VM_RUNTIME_MUTEXLOCKER_HPP 26 #define SHARE_VM_RUNTIME_MUTEXLOCKER_HPP 27 28 #include "memory/allocation.hpp" 29 #include "runtime/mutex.hpp" 30 #ifdef TARGET_OS_FAMILY_linux 31 # include "os_linux.inline.hpp" 32 #endif 33 #ifdef TARGET_OS_FAMILY_solaris 34 # include "os_solaris.inline.hpp" 35 #endif 36 #ifdef TARGET_OS_FAMILY_windows 37 # include "os_windows.inline.hpp" 38 #endif 39 #ifdef TARGET_OS_FAMILY_aix 40 # include "os_aix.inline.hpp" 41 #endif 42 #ifdef TARGET_OS_FAMILY_bsd 43 # include "os_bsd.inline.hpp" 44 #endif 45 46 // Mutexes used in the VM. 47 48 extern Mutex* Patching_lock; // a lock used to guard code patching of compiled code 49 extern Monitor* SystemDictionary_lock; // a lock on the system dictonary 50 extern Mutex* PackageTable_lock; // a lock on the class loader package table 51 extern Mutex* CompiledIC_lock; // a lock used to guard compiled IC patching and access 52 extern Mutex* InlineCacheBuffer_lock; // a lock used to guard the InlineCacheBuffer 53 extern Mutex* VMStatistic_lock; // a lock used to guard statistics count increment 54 extern Mutex* JNIGlobalHandle_lock; // a lock on creating JNI global handles 55 extern Mutex* JNIHandleBlockFreeList_lock; // a lock on the JNI handle block free list 56 extern Mutex* MemberNameTable_lock; // a lock on the MemberNameTable updates 57 extern Mutex* JmethodIdCreation_lock; // a lock on creating JNI method identifiers 58 extern Mutex* JfieldIdCreation_lock; // a lock on creating JNI static field identifiers 59 extern Monitor* JNICritical_lock; // a lock used while entering and exiting JNI critical regions, allows GC to sometimes get in 60 extern Mutex* JvmtiThreadState_lock; // a lock on modification of JVMTI thread data 61 extern Monitor* JvmtiPendingEvent_lock; // a lock on the JVMTI pending events list 62 extern Monitor* Heap_lock; // a lock on the heap 63 extern Mutex* ExpandHeap_lock; // a lock on expanding the heap 64 extern Mutex* AdapterHandlerLibrary_lock; // a lock on the AdapterHandlerLibrary 65 extern Mutex* SignatureHandlerLibrary_lock; // a lock on the SignatureHandlerLibrary 66 extern Mutex* VtableStubs_lock; // a lock on the VtableStubs 67 extern Mutex* SymbolTable_lock; // a lock on the symbol table 68 extern Mutex* StringTable_lock; // a lock on the interned string table 69 extern Monitor* StringDedupQueue_lock; // a lock on the string deduplication queue 70 extern Mutex* StringDedupTable_lock; // a lock on the string deduplication table 71 extern Mutex* CodeCache_lock; // a lock on the CodeCache, rank is special, use MutexLockerEx 72 extern Mutex* MethodData_lock; // a lock on installation of method data 73 extern Mutex* RetData_lock; // a lock on installation of RetData inside method data 74 extern Mutex* DerivedPointerTableGC_lock; // a lock to protect the derived pointer table 75 extern Monitor* VMOperationQueue_lock; // a lock on queue of vm_operations waiting to execute 76 extern Monitor* VMOperationRequest_lock; // a lock on Threads waiting for a vm_operation to terminate 77 extern Monitor* Safepoint_lock; // a lock used by the safepoint abstraction 78 extern Monitor* Threads_lock; // a lock on the Threads table of active Java threads 79 // (also used by Safepoints too to block threads creation/destruction) 80 extern Monitor* CGC_lock; // used for coordination between 81 // fore- & background GC threads. 82 extern Monitor* STS_lock; // used for joining/leaving SuspendibleThreadSet. 83 extern Monitor* SLT_lock; // used in CMS GC for acquiring PLL 84 extern Monitor* iCMS_lock; // CMS incremental mode start/stop notification 85 extern Monitor* FullGCCount_lock; // in support of "concurrent" full gc 86 extern Monitor* CMark_lock; // used for concurrent mark thread coordination 87 extern Mutex* CMRegionStack_lock; // used for protecting accesses to the CM region stack 88 extern Mutex* SATB_Q_FL_lock; // Protects SATB Q 89 // buffer free list. 90 extern Monitor* SATB_Q_CBL_mon; // Protects SATB Q 91 // completed buffer queue. 92 extern Mutex* Shared_SATB_Q_lock; // Lock protecting SATB 93 // queue shared by 94 // non-Java threads. 95 96 extern Mutex* DirtyCardQ_FL_lock; // Protects dirty card Q 97 // buffer free list. 98 extern Monitor* DirtyCardQ_CBL_mon; // Protects dirty card Q 99 // completed buffer queue. 100 extern Mutex* Shared_DirtyCardQ_lock; // Lock protecting dirty card 101 // queue shared by 102 // non-Java threads. 103 // (see option ExplicitGCInvokesConcurrent) 104 extern Mutex* ParGCRareEvent_lock; // Synchronizes various (rare) parallel GC ops. 105 extern Mutex* EvacFailureStack_lock; // guards the evac failure scan stack 106 extern Mutex* Compile_lock; // a lock held when Compilation is updating code (used to block CodeCache traversal, CHA updates, etc) 107 extern Monitor* MethodCompileQueue_lock; // a lock held when method compilations are enqueued, dequeued 108 extern Monitor* CompileThread_lock; // a lock held by compile threads during compilation system initialization 109 extern Mutex* CompileTaskAlloc_lock; // a lock held when CompileTasks are allocated 110 extern Mutex* CompileStatistics_lock; // a lock held when updating compilation statistics 111 extern Mutex* MultiArray_lock; // a lock used to guard allocation of multi-dim arrays 112 extern Monitor* Terminator_lock; // a lock used to guard termination of the vm 113 extern Monitor* BeforeExit_lock; // a lock used to guard cleanups and shutdown hooks 114 extern Monitor* Notify_lock; // a lock used to synchronize the start-up of the vm 115 extern Monitor* Interrupt_lock; // a lock used for condition variable mediated interrupt processing 116 extern Monitor* ProfileVM_lock; // a lock used for profiling the VMThread 117 extern Mutex* ProfilePrint_lock; // a lock used to serialize the printing of profiles 118 extern Mutex* ExceptionCache_lock; // a lock used to synchronize exception cache updates 119 extern Mutex* OsrList_lock; // a lock used to serialize access to OSR queues 120 121 #ifndef PRODUCT 122 extern Mutex* FullGCALot_lock; // a lock to make FullGCALot MT safe 123 #endif // PRODUCT 124 extern Mutex* Debug1_lock; // A bunch of pre-allocated locks that can be used for tracing 125 extern Mutex* Debug2_lock; // down synchronization related bugs! 126 extern Mutex* Debug3_lock; 127 128 extern Mutex* RawMonitor_lock; 129 extern Mutex* PerfDataMemAlloc_lock; // a lock on the allocator for PerfData memory for performance data 130 extern Mutex* PerfDataManager_lock; // a long on access to PerfDataManager resources 131 extern Mutex* ParkerFreeList_lock; 132 extern Mutex* OopMapCacheAlloc_lock; // protects allocation of oop_map caches 133 134 extern Mutex* FreeList_lock; // protects the free region list during safepoints 135 extern Monitor* SecondaryFreeList_lock; // protects the secondary free region list 136 extern Mutex* OldSets_lock; // protects the old region sets 137 extern Monitor* RootRegionScan_lock; // used to notify that the CM threads have finished scanning the IM snapshot regions 138 extern Mutex* MMUTracker_lock; // protects the MMU 139 // tracker data structures 140 extern Mutex* HotCardCache_lock; // protects the hot card cache 141 142 extern Mutex* Management_lock; // a lock used to serialize JVM management 143 extern Monitor* Service_lock; // a lock used for service thread operation 144 extern Monitor* PeriodicTask_lock; // protects the periodic task structure 145 146 #ifdef INCLUDE_TRACE 147 extern Mutex* JfrStacktrace_lock; // used to guard access to the JFR stacktrace table 148 extern Monitor* JfrMsg_lock; // protects JFR messaging 149 extern Mutex* JfrBuffer_lock; // protects JFR buffer operations 150 extern Mutex* JfrStream_lock; // protects JFR stream access 151 extern Mutex* JfrThreadGroups_lock; // protects JFR access to Thread Groups 152 #endif 153 154 #ifndef SUPPORTS_NATIVE_CX8 155 extern Mutex* UnsafeJlong_lock; // provides Unsafe atomic updates to jlongs on platforms that don't support cx8 156 #endif 157 158 // A MutexLocker provides mutual exclusion with respect to a given mutex 159 // for the scope which contains the locker. The lock is an OS lock, not 160 // an object lock, and the two do not interoperate. Do not use Mutex-based 161 // locks to lock on Java objects, because they will not be respected if a 162 // that object is locked using the Java locking mechanism. 163 // 164 // NOTE WELL!! 165 // 166 // See orderAccess.hpp. We assume throughout the VM that MutexLocker's 167 // and friends constructors do a fence, a lock and an acquire *in that 168 // order*. And that their destructors do a release and unlock, in *that* 169 // order. If their implementations change such that these assumptions 170 // are violated, a whole lot of code will break. 171 172 // Print all mutexes/monitors that are currently owned by a thread; called 173 // by fatal error handler. 174 void print_owned_locks_on_error(outputStream* st); 175 176 char *lock_name(Mutex *mutex); 177 178 class MutexLocker: StackObj { 179 private: 180 Monitor * _mutex; 181 public: 182 MutexLocker(Monitor * mutex) { 183 assert(mutex->rank() != Mutex::special, 184 "Special ranked mutex should only use MutexLockerEx"); 185 _mutex = mutex; 186 _mutex->lock(); 187 } 188 189 // Overloaded constructor passing current thread 190 MutexLocker(Monitor * mutex, Thread *thread) { 191 assert(mutex->rank() != Mutex::special, 192 "Special ranked mutex should only use MutexLockerEx"); 193 _mutex = mutex; 194 _mutex->lock(thread); 195 } 196 197 ~MutexLocker() { 198 _mutex->unlock(); 199 } 200 201 }; 202 203 // for debugging: check that we're already owning this lock (or are at a safepoint) 204 #ifdef ASSERT 205 void assert_locked_or_safepoint(const Monitor * lock); 206 void assert_lock_strong(const Monitor * lock); 207 #else 208 #define assert_locked_or_safepoint(lock) 209 #define assert_lock_strong(lock) 210 #endif 211 212 // A MutexLockerEx behaves like a MutexLocker when its constructor is 213 // called with a Mutex. Unlike a MutexLocker, its constructor can also be 214 // called with NULL, in which case the MutexLockerEx is a no-op. There 215 // is also a corresponding MutexUnlockerEx. We want to keep the 216 // basic MutexLocker as fast as possible. MutexLockerEx can also lock 217 // without safepoint check. 218 219 class MutexLockerEx: public StackObj { 220 private: 221 Monitor * _mutex; 222 public: 223 MutexLockerEx(Monitor * mutex, bool no_safepoint_check = !Mutex::_no_safepoint_check_flag) { 224 _mutex = mutex; 225 if (_mutex != NULL) { 226 assert(mutex->rank() > Mutex::special || no_safepoint_check, 227 "Mutexes with rank special or lower should not do safepoint checks"); 228 if (no_safepoint_check) 229 _mutex->lock_without_safepoint_check(); 230 else 231 _mutex->lock(); 232 } 233 } 234 235 ~MutexLockerEx() { 236 if (_mutex != NULL) { 237 _mutex->unlock(); 238 } 239 } 240 }; 241 242 // A MonitorLockerEx is like a MutexLockerEx above, except it takes 243 // a possibly null Monitor, and allows wait/notify as well which are 244 // delegated to the underlying Monitor. 245 246 class MonitorLockerEx: public MutexLockerEx { 247 private: 248 Monitor * _monitor; 249 public: 250 MonitorLockerEx(Monitor* monitor, 251 bool no_safepoint_check = !Mutex::_no_safepoint_check_flag): 252 MutexLockerEx(monitor, no_safepoint_check), 253 _monitor(monitor) { 254 // Superclass constructor did locking 255 } 256 257 ~MonitorLockerEx() { 258 #ifdef ASSERT 259 if (_monitor != NULL) { 260 assert_lock_strong(_monitor); 261 } 262 #endif // ASSERT 263 // Superclass destructor will do unlocking 264 } 265 266 bool wait(bool no_safepoint_check = !Mutex::_no_safepoint_check_flag, 267 long timeout = 0, 268 bool as_suspend_equivalent = !Mutex::_as_suspend_equivalent_flag) { 269 if (_monitor != NULL) { 270 return _monitor->wait(no_safepoint_check, timeout, as_suspend_equivalent); 271 } 272 return false; 273 } 274 275 bool notify_all() { 276 if (_monitor != NULL) { 277 return _monitor->notify_all(); 278 } 279 return true; 280 } 281 282 bool notify() { 283 if (_monitor != NULL) { 284 return _monitor->notify(); 285 } 286 return true; 287 } 288 }; 289 290 291 292 // A GCMutexLocker is usually initialized with a mutex that is 293 // automatically acquired in order to do GC. The function that 294 // synchronizes using a GCMutexLocker may be called both during and between 295 // GC's. Thus, it must acquire the mutex if GC is not in progress, but not 296 // if GC is in progress (since the mutex is already held on its behalf.) 297 298 class GCMutexLocker: public StackObj { 299 private: 300 Monitor * _mutex; 301 bool _locked; 302 public: 303 GCMutexLocker(Monitor * mutex); 304 ~GCMutexLocker() { if (_locked) _mutex->unlock(); } 305 }; 306 307 308 309 // A MutexUnlocker temporarily exits a previously 310 // entered mutex for the scope which contains the unlocker. 311 312 class MutexUnlocker: StackObj { 313 private: 314 Monitor * _mutex; 315 316 public: 317 MutexUnlocker(Monitor * mutex) { 318 _mutex = mutex; 319 _mutex->unlock(); 320 } 321 322 ~MutexUnlocker() { 323 _mutex->lock(); 324 } 325 }; 326 327 // A MutexUnlockerEx temporarily exits a previously 328 // entered mutex for the scope which contains the unlocker. 329 330 class MutexUnlockerEx: StackObj { 331 private: 332 Monitor * _mutex; 333 bool _no_safepoint_check; 334 335 public: 336 MutexUnlockerEx(Monitor * mutex, bool no_safepoint_check = !Mutex::_no_safepoint_check_flag) { 337 _mutex = mutex; 338 _no_safepoint_check = no_safepoint_check; 339 _mutex->unlock(); 340 } 341 342 ~MutexUnlockerEx() { 343 if (_no_safepoint_check == Mutex::_no_safepoint_check_flag) { 344 _mutex->lock_without_safepoint_check(); 345 } else { 346 _mutex->lock(); 347 } 348 } 349 }; 350 351 #ifndef PRODUCT 352 // 353 // A special MutexLocker that allows: 354 // - reentrant locking 355 // - locking out of order 356 // 357 // Only too be used for verify code, where we can relaxe out dead-lock 358 // dection code a bit (unsafe, but probably ok). This code is NEVER to 359 // be included in a product version. 360 // 361 class VerifyMutexLocker: StackObj { 362 private: 363 Monitor * _mutex; 364 bool _reentrant; 365 public: 366 VerifyMutexLocker(Monitor * mutex) { 367 _mutex = mutex; 368 _reentrant = mutex->owned_by_self(); 369 if (!_reentrant) { 370 // We temp. diable strict safepoint checking, while we require the lock 371 FlagSetting fs(StrictSafepointChecks, false); 372 _mutex->lock(); 373 } 374 } 375 376 ~VerifyMutexLocker() { 377 if (!_reentrant) { 378 _mutex->unlock(); 379 } 380 } 381 }; 382 383 #endif 384 385 #endif // SHARE_VM_RUNTIME_MUTEXLOCKER_HPP