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