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