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24 
25 #ifndef SHARE_RUNTIME_MUTEXLOCKER_HPP
26 #define SHARE_RUNTIME_MUTEXLOCKER_HPP
27 
28 #include "memory/allocation.hpp"
29 #include "runtime/flags/flagSetting.hpp"
30 #include "runtime/mutex.hpp"
31 
32 // Mutexes used in the VM.
33 
34 extern Mutex*   Patching_lock;                   // a lock used to guard code patching of compiled code
35 extern Mutex*   CompiledMethod_lock;             // a lock used to guard a compiled method and OSR queues
36 extern Monitor* SystemDictionary_lock;           // a lock on the system dictionary
37 extern Mutex*   ProtectionDomainSet_lock;        // a lock on the pd_set list in the system dictionary
38 extern Mutex*   SharedDictionary_lock;           // a lock on the CDS shared dictionary
39 extern Mutex*   Module_lock;                     // a lock on module and package related data structures
40 extern Mutex*   CompiledIC_lock;                 // a lock used to guard compiled IC patching and access
41 extern Mutex*   InlineCacheBuffer_lock;          // a lock used to guard the InlineCacheBuffer
42 extern Mutex*   VMStatistic_lock;                // a lock used to guard statistics count increment
43 extern Mutex*   JNIHandleBlockFreeList_lock;     // a lock on the JNI handle block free list
44 extern Mutex*   JmethodIdCreation_lock;          // a lock on creating JNI method identifiers
45 extern Mutex*   JfieldIdCreation_lock;           // a lock on creating JNI static field identifiers
46 extern Monitor* JNICritical_lock;                // a lock used while entering and exiting JNI critical regions, allows GC to sometimes get in
47 extern Mutex*   JvmtiThreadState_lock;           // a lock on modification of JVMTI thread data
48 extern Monitor* EscapeBarrier_lock;              // a lock to sync reallocating and relocking objects because of JVMTI access
49 extern Monitor* Heap_lock;                       // a lock on the heap
50 extern Mutex*   ExpandHeap_lock;                 // a lock on expanding the heap
51 extern Mutex*   AdapterHandlerLibrary_lock;      // a lock on the AdapterHandlerLibrary
52 extern Mutex*   SignatureHandlerLibrary_lock;    // a lock on the SignatureHandlerLibrary
53 extern Mutex*   VtableStubs_lock;                // a lock on the VtableStubs
54 extern Mutex*   SymbolArena_lock;                // a lock on the symbol table arena
55 extern Monitor* StringDedupQueue_lock;           // a lock on the string deduplication queue
56 extern Mutex*   StringDedupTable_lock;           // a lock on the string deduplication table
57 extern Monitor* CodeCache_lock;                  // a lock on the CodeCache, rank is special
58 extern Monitor* CodeSweeper_lock;                // a lock used by the sweeper only for wait notify
59 extern Mutex*   MethodData_lock;                 // a lock on installation of method data
60 extern Mutex*   TouchedMethodLog_lock;           // a lock on allocation of LogExecutedMethods info
61 extern Mutex*   RetData_lock;                    // a lock on installation of RetData inside method data
62 extern Monitor* VMOperation_lock;                // a lock on queue of vm_operations waiting to execute
63 extern Monitor* Threads_lock;                    // a lock on the Threads table of active Java threads
64                                                  // (also used by Safepoints too to block threads creation/destruction)
65 extern Mutex*   NonJavaThreadsList_lock;         // a lock on the NonJavaThreads list
66 extern Mutex*   NonJavaThreadsListSync_lock;     // a lock for NonJavaThreads list synchronization
67 extern Monitor* CGC_lock;                        // used for coordination between
68                                                  // fore- & background GC threads.
69 extern Monitor* STS_lock;                        // used for joining/leaving SuspendibleThreadSet.
70 extern Monitor* FullGCCount_lock;                // in support of "concurrent" full gc
71 extern Monitor* G1OldGCCount_lock;               // in support of "concurrent" full gc
72 extern Mutex*   Shared_DirtyCardQ_lock;          // Lock protecting dirty card
73                                                  // queue shared by
74                                                  // non-Java threads.
75 extern Mutex*   G1DetachedRefinementStats_lock;  // Lock protecting detached refinement stats
76 extern Mutex*   MarkStackFreeList_lock;          // Protects access to the global mark stack free list.
77 extern Mutex*   MarkStackChunkList_lock;         // Protects access to the global mark stack chunk list.
78 extern Mutex*   MonitoringSupport_lock;          // Protects updates to the serviceability memory pools.
79 extern Mutex*   ParGCRareEvent_lock;             // Synchronizes various (rare) parallel GC ops.
80 extern Monitor* ConcurrentGCBreakpoints_lock;    // Protects concurrent GC breakpoint management
81 extern Mutex*   Compile_lock;                    // a lock held when Compilation is updating code (used to block CodeCache traversal, CHA updates, etc)
82 extern Monitor* MethodCompileQueue_lock;         // a lock held when method compilations are enqueued, dequeued
83 extern Monitor* CompileThread_lock;              // a lock held by compile threads during compilation system initialization
84 extern Monitor* Compilation_lock;                // a lock used to pause compilation
85 extern Mutex*   CompileTaskAlloc_lock;           // a lock held when CompileTasks are allocated
86 extern Mutex*   CompileStatistics_lock;          // a lock held when updating compilation statistics
87 extern Mutex*   DirectivesStack_lock;            // a lock held when mutating the dirstack and ref counting directives
88 extern Mutex*   MultiArray_lock;                 // a lock used to guard allocation of multi-dim arrays
89 extern Monitor* Terminator_lock;                 // a lock used to guard termination of the vm
90 extern Monitor* InitCompleted_lock;              // a lock used to signal threads waiting on init completed
91 extern Monitor* BeforeExit_lock;                 // a lock used to guard cleanups and shutdown hooks
92 extern Monitor* Notify_lock;                     // a lock used to synchronize the start-up of the vm
93 extern Mutex*   ProfilePrint_lock;               // a lock used to serialize the printing of profiles
94 extern Mutex*   ExceptionCache_lock;             // a lock used to synchronize exception cache updates
95 extern Mutex*   NMethodSweeperStats_lock;        // a lock used to serialize access to sweeper statistics
96 
97 #ifndef PRODUCT
98 extern Mutex*   FullGCALot_lock;                 // a lock to make FullGCALot MT safe
99 #endif // PRODUCT
100 extern Mutex*   Debug1_lock;                     // A bunch of pre-allocated locks that can be used for tracing
101 extern Mutex*   Debug2_lock;                     // down synchronization related bugs!
102 extern Mutex*   Debug3_lock;
103 
104 extern Mutex*   RawMonitor_lock;
105 extern Mutex*   PerfDataMemAlloc_lock;           // a lock on the allocator for PerfData memory for performance data
106 extern Mutex*   PerfDataManager_lock;            // a long on access to PerfDataManager resources
107 extern Mutex*   OopMapCacheAlloc_lock;           // protects allocation of oop_map caches
108 
109 extern Mutex*   FreeList_lock;                   // protects the free region list during safepoints
110 extern Mutex*   OldSets_lock;                    // protects the old region sets
111 extern Mutex*   Uncommit_lock;                   // protects the uncommit list when not at safepoints
112 extern Monitor* RootRegionScan_lock;             // used to notify that the CM threads have finished scanning the IM snapshot regions
113 
114 extern Mutex*   Management_lock;                 // a lock used to serialize JVM management
115 extern Monitor* MonitorDeflation_lock;           // a lock used for monitor deflation thread operation
116 extern Monitor* Service_lock;                    // a lock used for service thread operation
117 extern Monitor* Notification_lock;               // a lock used for notification thread operation
118 extern Monitor* PeriodicTask_lock;               // protects the periodic task structure
119 extern Monitor* RedefineClasses_lock;            // locks classes from parallel redefinition
120 extern Mutex*   Verify_lock;                     // synchronize initialization of verify library
121 extern Monitor* Zip_lock;                        // synchronize initialization of zip library
122 extern Monitor* ThreadsSMRDelete_lock;           // Used by ThreadsSMRSupport to take pressure off the Threads_lock
123 extern Mutex*   ThreadIdTableCreate_lock;        // Used by ThreadIdTable to lazily create the thread id table
124 extern Mutex*   SharedDecoder_lock;              // serializes access to the decoder during normal (not error reporting) use
125 extern Mutex*   DCmdFactory_lock;                // serialize access to DCmdFactory information
126 #if INCLUDE_NMT
127 extern Mutex*   NMTQuery_lock;                   // serialize NMT Dcmd queries
128 #endif
129 #if INCLUDE_CDS
130 #if INCLUDE_JVMTI
131 extern Mutex*   CDSClassFileStream_lock;         // FileMapInfo::open_stream_for_jvmti
132 #endif
133 extern Mutex*   DumpTimeTable_lock;              // SystemDictionaryShared::find_or_allocate_info_for
134 extern Mutex*   CDSLambda_lock;                  // SystemDictionaryShared::get_shared_lambda_proxy_class
135 extern Mutex*   DumpRegion_lock;                 // Symbol::operator new(size_t sz, int len)
136 extern Mutex*   ClassListFile_lock;              // ClassListWriter()
137 #endif // INCLUDE_CDS
138 #if INCLUDE_JFR
139 extern Mutex*   JfrStacktrace_lock;              // used to guard access to the JFR stacktrace table
140 extern Monitor* JfrMsg_lock;                     // protects JFR messaging
141 extern Mutex*   JfrBuffer_lock;                  // protects JFR buffer operations
142 extern Mutex*   JfrStream_lock;                  // protects JFR stream access
143 extern Monitor* JfrThreadSampler_lock;           // used to suspend/resume JFR thread sampler
144 #endif
145 
146 #ifndef SUPPORTS_NATIVE_CX8
147 extern Mutex*   UnsafeJlong_lock;                // provides Unsafe atomic updates to jlongs on platforms that don't support cx8
148 #endif
149 
150 extern Mutex*   MetaspaceExpand_lock;            // protects Metaspace virtualspace and chunk expansions
151 extern Mutex*   ClassLoaderDataGraph_lock;       // protects CLDG list, needed for concurrent unloading
152 
153 
154 extern Mutex*   CodeHeapStateAnalytics_lock;     // lock print functions against concurrent analyze functions.
155                                                  // Only used locally in PrintCodeCacheLayout processing.
156 
157 #if INCLUDE_JVMCI
158 extern Monitor* JVMCI_lock;                      // Monitor to control initialization of JVMCI
159 #endif
160 
161 extern Mutex* tty_lock;                          // lock to synchronize output.
162 
163 // A MutexLocker provides mutual exclusion with respect to a given mutex
164 // for the scope which contains the locker.  The lock is an OS lock, not
165 // an object lock, and the two do not interoperate.  Do not use Mutex-based
166 // locks to lock on Java objects, because they will not be respected if a
167 // that object is locked using the Java locking mechanism.
168 //
169 //                NOTE WELL!!
170 //
171 // See orderAccess.hpp.  We assume throughout the VM that MutexLocker's
172 // and friends constructors do a fence, a lock and an acquire *in that
173 // order*.  And that their destructors do a release and unlock, in *that*
174 // order.  If their implementations change such that these assumptions
175 // are violated, a whole lot of code will break.
176 
177 // Print all mutexes/monitors that are currently owned by a thread; called
178 // by fatal error handler.
179 void print_owned_locks_on_error(outputStream* st);
180 
181 char *lock_name(Mutex *mutex);
182 
183 // for debugging: check that we're already owning this lock (or are at a safepoint / handshake)
184 #ifdef ASSERT
185 void assert_locked_or_safepoint(const Mutex* lock);
186 void assert_locked_or_safepoint_weak(const Mutex* lock);
187 void assert_lock_strong(const Mutex* lock);
188 void assert_locked_or_safepoint_or_handshake(const Mutex* lock, const JavaThread* thread);
189 #else
190 #define assert_locked_or_safepoint(lock)
191 #define assert_locked_or_safepoint_weak(lock)
192 #define assert_lock_strong(lock)
193 #define assert_locked_or_safepoint_or_handshake(lock, thread)
194 #endif
195 
196 class MutexLocker: public StackObj {
197  protected:
198   Mutex* _mutex;
199  private:
200  public:
MutexLocker(Mutex * mutex,Mutex::SafepointCheckFlag flag=Mutex::_safepoint_check_flag)201   MutexLocker(Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
202     _mutex(mutex) {
203     bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag;
204     if (_mutex != NULL) {
205       assert(_mutex->rank() > Mutex::special || no_safepoint_check,
206              "Mutexes with rank special or lower should not do safepoint checks");
207       if (no_safepoint_check) {
208         _mutex->lock_without_safepoint_check();
209       } else {
210         _mutex->lock();
211       }
212     }
213   }
214 
MutexLocker(Thread * thread,Mutex * mutex,Mutex::SafepointCheckFlag flag=Mutex::_safepoint_check_flag)215   MutexLocker(Thread* thread, Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
216     _mutex(mutex) {
217     bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag;
218     if (_mutex != NULL) {
219       assert(_mutex->rank() > Mutex::special || no_safepoint_check,
220              "Mutexes with rank special or lower should not do safepoint checks");
221       if (no_safepoint_check) {
222         _mutex->lock_without_safepoint_check(thread);
223       } else {
224         _mutex->lock(thread);
225       }
226     }
227   }
228 
~MutexLocker()229   ~MutexLocker() {
230     if (_mutex != NULL) {
231       assert_lock_strong(_mutex);
232       _mutex->unlock();
233     }
234   }
235 };
236 
237 // A MonitorLocker is like a MutexLocker above, except it allows
238 // wait/notify as well which are delegated to the underlying Monitor.
239 // It also disallows NULL.
240 
241 class MonitorLocker: public MutexLocker {
242   Mutex::SafepointCheckFlag _flag;
243   Monitor* _monitor;
244  public:
MonitorLocker(Monitor * monitor,Mutex::SafepointCheckFlag flag=Mutex::_safepoint_check_flag)245   MonitorLocker(Monitor* monitor, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
246     MutexLocker(monitor, flag), _flag(flag), _monitor(monitor) {
247     // Superclass constructor did locking
248     assert(_monitor != NULL, "NULL monitor not allowed");
249   }
250 
MonitorLocker(Thread * thread,Monitor * monitor,Mutex::SafepointCheckFlag flag=Mutex::_safepoint_check_flag)251   MonitorLocker(Thread* thread, Monitor* monitor, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
252     MutexLocker(thread, monitor, flag), _flag(flag), _monitor(monitor)  {
253     // Superclass constructor did locking
254     assert(_monitor != NULL, "NULL monitor not allowed");
255   }
256 
wait(int64_t timeout=0,bool as_suspend_equivalent=!Mutex::_as_suspend_equivalent_flag)257   bool wait(int64_t timeout = 0,
258             bool as_suspend_equivalent = !Mutex::_as_suspend_equivalent_flag) {
259     if (_flag == Mutex::_safepoint_check_flag) {
260       return _monitor->wait(timeout, as_suspend_equivalent);
261     } else {
262       return _monitor->wait_without_safepoint_check(timeout);
263     }
264     return false;
265   }
266 
notify_all()267   void notify_all() {
268     _monitor->notify_all();
269   }
270 
notify()271   void notify() {
272     _monitor->notify();
273   }
274 };
275 
276 
277 // A GCMutexLocker is usually initialized with a mutex that is
278 // automatically acquired in order to do GC.  The function that
279 // synchronizes using a GCMutexLocker may be called both during and between
280 // GC's.  Thus, it must acquire the mutex if GC is not in progress, but not
281 // if GC is in progress (since the mutex is already held on its behalf.)
282 
283 class GCMutexLocker: public StackObj {
284 private:
285   Mutex* _mutex;
286   bool _locked;
287 public:
288   GCMutexLocker(Mutex* mutex);
~GCMutexLocker()289   ~GCMutexLocker() { if (_locked) _mutex->unlock(); }
290 };
291 
292 // A MutexUnlocker temporarily exits a previously
293 // entered mutex for the scope which contains the unlocker.
294 
295 class MutexUnlocker: StackObj {
296  private:
297   Mutex* _mutex;
298   bool _no_safepoint_check;
299 
300  public:
MutexUnlocker(Mutex * mutex,Mutex::SafepointCheckFlag flag=Mutex::_safepoint_check_flag)301   MutexUnlocker(Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
302     _mutex(mutex),
303     _no_safepoint_check(flag == Mutex::_no_safepoint_check_flag) {
304     _mutex->unlock();
305   }
306 
~MutexUnlocker()307   ~MutexUnlocker() {
308     if (_no_safepoint_check) {
309       _mutex->lock_without_safepoint_check();
310     } else {
311       _mutex->lock();
312     }
313   }
314 };
315 
316 #endif // SHARE_RUNTIME_MUTEXLOCKER_HPP
317