1 /*
2 * Copyright (c) 1997, 2019, 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
21 * questions.
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23 */
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;
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* JNIGlobalAlloc_lock; // JNI global storage allocate list lock
44 extern Mutex* JNIGlobalActive_lock; // JNI global storage active list lock
45 extern Mutex* JNIWeakAlloc_lock; // JNI weak storage allocate list lock
46 extern Mutex* JNIWeakActive_lock; // JNI weak storage active list lock
47 extern Mutex* StringTableWeakAlloc_lock; // StringTable weak storage allocate list lock
48 extern Mutex* StringTableWeakActive_lock; // STringTable weak storage active list lock
49 extern Mutex* JNIHandleBlockFreeList_lock; // a lock on the JNI handle block free list
50 extern Mutex* VMWeakAlloc_lock; // VM Weak Handles storage allocate list lock
51 extern Mutex* VMWeakActive_lock; // VM Weak Handles storage active list lock
52 extern Mutex* ResolvedMethodTableWeakAlloc_lock; // ResolvedMethodTable weak storage allocate list
53 extern Mutex* ResolvedMethodTableWeakActive_lock; // ResolvedMethodTable weak storage active list
54 extern Mutex* JmethodIdCreation_lock; // a lock on creating JNI method identifiers
55 extern Mutex* JfieldIdCreation_lock; // a lock on creating JNI static field identifiers
56 extern Monitor* JNICritical_lock; // a lock used while entering and exiting JNI critical regions, allows GC to sometimes get in
57 extern Mutex* JvmtiThreadState_lock; // a lock on modification of JVMTI thread data
58 extern Monitor* Heap_lock; // a lock on the heap
59 extern Mutex* ExpandHeap_lock; // a lock on expanding the heap
60 extern Mutex* AdapterHandlerLibrary_lock; // a lock on the AdapterHandlerLibrary
61 extern Mutex* SignatureHandlerLibrary_lock; // a lock on the SignatureHandlerLibrary
62 extern Mutex* VtableStubs_lock; // a lock on the VtableStubs
63 extern Mutex* SymbolArena_lock; // a lock on the symbol table arena
64 extern Monitor* StringDedupQueue_lock; // a lock on the string deduplication queue
65 extern Mutex* StringDedupTable_lock; // a lock on the string deduplication table
66 extern Monitor* CodeCache_lock; // a lock on the CodeCache, rank is special, use MutexLockerEx
67 extern Mutex* MethodData_lock; // a lock on installation of method data
68 extern Mutex* TouchedMethodLog_lock; // a lock on allocation of LogExecutedMethods info
69 extern Mutex* RetData_lock; // a lock on installation of RetData inside method data
70 extern Mutex* DerivedPointerTableGC_lock; // a lock to protect the derived pointer table
71 extern Monitor* CGCPhaseManager_lock; // a lock to protect a concurrent GC's phase management
72 extern Monitor* VMOperationQueue_lock; // a lock on queue of vm_operations waiting to execute
73 extern Monitor* VMOperationRequest_lock; // a lock on Threads waiting for a vm_operation to terminate
74 extern Monitor* Threads_lock; // a lock on the Threads table of active Java threads
75 // (also used by Safepoints too to block threads creation/destruction)
76 extern Mutex* NonJavaThreadsList_lock; // a lock on the NonJavaThreads list
77 extern Mutex* NonJavaThreadsListSync_lock; // a lock for NonJavaThreads list synchronization
78 extern Monitor* CGC_lock; // used for coordination between
79 // fore- & background GC threads.
80 extern Monitor* STS_lock; // used for joining/leaving SuspendibleThreadSet.
81 extern Monitor* FullGCCount_lock; // in support of "concurrent" full gc
82 extern Monitor* SATB_Q_CBL_mon; // Protects SATB Q
83 // completed buffer queue.
84 extern Monitor* DirtyCardQ_CBL_mon; // Protects dirty card Q
85 // completed buffer queue.
86 extern Mutex* Shared_DirtyCardQ_lock; // Lock protecting dirty card
87 // queue shared by
88 // non-Java threads.
89 extern Mutex* MarkStackFreeList_lock; // Protects access to the global mark stack free list.
90 extern Mutex* MarkStackChunkList_lock; // Protects access to the global mark stack chunk list.
91 extern Mutex* MonitoringSupport_lock; // Protects updates to the serviceability memory pools.
92 extern Mutex* ParGCRareEvent_lock; // Synchronizes various (rare) parallel GC ops.
93 extern Mutex* Compile_lock; // a lock held when Compilation is updating code (used to block CodeCache traversal, CHA updates, etc)
94 extern Monitor* MethodCompileQueue_lock; // a lock held when method compilations are enqueued, dequeued
95 extern Monitor* CompileThread_lock; // a lock held by compile threads during compilation system initialization
96 extern Monitor* Compilation_lock; // a lock used to pause compilation
97 extern Mutex* CompileTaskAlloc_lock; // a lock held when CompileTasks are allocated
98 extern Mutex* CompileStatistics_lock; // a lock held when updating compilation statistics
99 extern Mutex* DirectivesStack_lock; // a lock held when mutating the dirstack and ref counting directives
100 extern Mutex* MultiArray_lock; // a lock used to guard allocation of multi-dim arrays
101 extern Monitor* Terminator_lock; // a lock used to guard termination of the vm
102 extern Monitor* InitCompleted_lock; // a lock used to signal threads waiting on init completed
103 extern Monitor* BeforeExit_lock; // a lock used to guard cleanups and shutdown hooks
104 extern Monitor* Notify_lock; // a lock used to synchronize the start-up of the vm
105 extern Mutex* ProfilePrint_lock; // a lock used to serialize the printing of profiles
106 extern Mutex* ExceptionCache_lock; // a lock used to synchronize exception cache updates
107 extern Mutex* OsrList_lock; // a lock used to serialize access to OSR queues
108 extern Mutex* NMethodSweeperStats_lock; // a lock used to serialize access to sweeper statistics
109
110 #ifndef PRODUCT
111 extern Mutex* FullGCALot_lock; // a lock to make FullGCALot MT safe
112 #endif // PRODUCT
113 extern Mutex* Debug1_lock; // A bunch of pre-allocated locks that can be used for tracing
114 extern Mutex* Debug2_lock; // down synchronization related bugs!
115 extern Mutex* Debug3_lock;
116
117 extern Mutex* RawMonitor_lock;
118 extern Mutex* PerfDataMemAlloc_lock; // a lock on the allocator for PerfData memory for performance data
119 extern Mutex* PerfDataManager_lock; // a long on access to PerfDataManager resources
120 extern Mutex* ParkerFreeList_lock;
121 extern Mutex* OopMapCacheAlloc_lock; // protects allocation of oop_map caches
122
123 extern Mutex* FreeList_lock; // protects the free region list during safepoints
124 extern Mutex* OldSets_lock; // protects the old region sets
125 extern Monitor* RootRegionScan_lock; // used to notify that the CM threads have finished scanning the IM snapshot regions
126
127 extern Mutex* Management_lock; // a lock used to serialize JVM management
128 extern Monitor* Service_lock; // a lock used for service thread operation
129 extern Monitor* PeriodicTask_lock; // protects the periodic task structure
130 extern Monitor* RedefineClasses_lock; // locks classes from parallel redefinition
131 extern Monitor* ThreadsSMRDelete_lock; // Used by ThreadsSMRSupport to take pressure off the Threads_lock
132 extern Mutex* SharedDecoder_lock; // serializes access to the decoder during normal (not error reporting) use
133 extern Mutex* DCmdFactory_lock; // serialize access to DCmdFactory information
134 #if INCLUDE_NMT
135 extern Mutex* NMTQuery_lock; // serialize NMT Dcmd queries
136 #endif
137 #if INCLUDE_CDS && INCLUDE_JVMTI
138 extern Mutex* CDSClassFileStream_lock; // FileMapInfo::open_stream_for_jvmti
139 #endif
140 #if INCLUDE_JFR
141 extern Mutex* JfrStacktrace_lock; // used to guard access to the JFR stacktrace table
142 extern Monitor* JfrMsg_lock; // protects JFR messaging
143 extern Mutex* JfrBuffer_lock; // protects JFR buffer operations
144 extern Mutex* JfrStream_lock; // protects JFR stream access
145 extern Monitor* JfrThreadSampler_lock; // used to suspend/resume JFR thread sampler
146 #endif
147
148 #ifndef SUPPORTS_NATIVE_CX8
149 extern Mutex* UnsafeJlong_lock; // provides Unsafe atomic updates to jlongs on platforms that don't support cx8
150 #endif
151
152 extern Mutex* MetaspaceExpand_lock; // protects Metaspace virtualspace and chunk expansions
153 extern Mutex* ClassLoaderDataGraph_lock; // protects CLDG list, needed for concurrent unloading
154
155
156 extern Monitor* CodeHeapStateAnalytics_lock; // lock print functions against concurrent analyze functions.
157 // Only used locally in PrintCodeCacheLayout processing.
158
159 // A MutexLocker provides mutual exclusion with respect to a given mutex
160 // for the scope which contains the locker. The lock is an OS lock, not
161 // an object lock, and the two do not interoperate. Do not use Mutex-based
162 // locks to lock on Java objects, because they will not be respected if a
163 // that object is locked using the Java locking mechanism.
164 //
165 // NOTE WELL!!
166 //
167 // See orderAccess.hpp. We assume throughout the VM that MutexLocker's
168 // and friends constructors do a fence, a lock and an acquire *in that
169 // order*. And that their destructors do a release and unlock, in *that*
170 // order. If their implementations change such that these assumptions
171 // are violated, a whole lot of code will break.
172
173 // Print all mutexes/monitors that are currently owned by a thread; called
174 // by fatal error handler.
175 void print_owned_locks_on_error(outputStream* st);
176
177 char *lock_name(Mutex *mutex);
178
179 class MutexLocker: StackObj {
180 private:
181 Monitor * _mutex;
182 public:
183 MutexLocker(Monitor * mutex) {
184 assert(mutex->rank() != Mutex::special,
185 "Special ranked mutex should only use MutexLockerEx");
186 _mutex = mutex;
187 _mutex->lock();
188 }
189
190 // Overloaded constructor passing current thread
191 MutexLocker(Monitor * mutex, Thread *thread) {
192 assert(mutex->rank() != Mutex::special,
193 "Special ranked mutex should only use MutexLockerEx");
194 _mutex = mutex;
195 _mutex->lock(thread);
196 }
197
198 ~MutexLocker() {
199 _mutex->unlock();
200 }
201
202 };
203
204 // for debugging: check that we're already owning this lock (or are at a safepoint)
205 #ifdef ASSERT
206 void assert_locked_or_safepoint(const Monitor * lock);
207 void assert_locked_or_safepoint_weak(const Monitor * lock);
208 void assert_lock_strong(const Monitor * lock);
209 #else
210 #define assert_locked_or_safepoint(lock)
211 #define assert_locked_or_safepoint_weak(lock)
212 #define assert_lock_strong(lock)
213 #endif
214
215 // A MutexLockerEx behaves like a MutexLocker when its constructor is
216 // called with a Mutex. Unlike a MutexLocker, its constructor can also be
217 // called with NULL, in which case the MutexLockerEx is a no-op. There
218 // is also a corresponding MutexUnlockerEx. We want to keep the
219 // basic MutexLocker as fast as possible. MutexLockerEx can also lock
220 // without safepoint check.
221
222 class MutexLockerEx: public StackObj {
223 private:
224 Monitor * _mutex;
225 public:
226 MutexLockerEx(Monitor * mutex, bool no_safepoint_check = !Mutex::_no_safepoint_check_flag) {
227 _mutex = mutex;
228 if (_mutex != NULL) {
229 assert(mutex->rank() > Mutex::special || no_safepoint_check,
230 "Mutexes with rank special or lower should not do safepoint checks");
231 if (no_safepoint_check)
232 _mutex->lock_without_safepoint_check();
233 else
234 _mutex->lock();
235 }
236 }
237
238 ~MutexLockerEx() {
239 if (_mutex != NULL) {
240 _mutex->unlock();
241 }
242 }
243 };
244
245 // A MonitorLockerEx is like a MutexLockerEx above, except it takes
246 // a possibly null Monitor, and allows wait/notify as well which are
247 // delegated to the underlying Monitor.
248
249 class MonitorLockerEx: public MutexLockerEx {
250 private:
251 Monitor * _monitor;
252 public:
253 MonitorLockerEx(Monitor* monitor,
254 bool no_safepoint_check = !Mutex::_no_safepoint_check_flag):
255 MutexLockerEx(monitor, no_safepoint_check),
256 _monitor(monitor) {
257 // Superclass constructor did locking
258 }
259
260 ~MonitorLockerEx() {
261 #ifdef ASSERT
262 if (_monitor != NULL) {
263 assert_lock_strong(_monitor);
264 }
265 #endif // ASSERT
266 // Superclass destructor will do unlocking
267 }
268
269 bool wait(bool no_safepoint_check = !Mutex::_no_safepoint_check_flag,
270 long timeout = 0,
271 bool as_suspend_equivalent = !Mutex::_as_suspend_equivalent_flag) {
272 if (_monitor != NULL) {
273 return _monitor->wait(no_safepoint_check, timeout, as_suspend_equivalent);
274 }
275 return false;
276 }
277
278 void notify_all() {
279 if (_monitor != NULL) {
280 _monitor->notify_all();
281 }
282 }
283
284 void notify() {
285 if (_monitor != NULL) {
286 _monitor->notify();
287 }
288 }
289 };
290
291
292
293 // A GCMutexLocker is usually initialized with a mutex that is
294 // automatically acquired in order to do GC. The function that
295 // synchronizes using a GCMutexLocker may be called both during and between
296 // GC's. Thus, it must acquire the mutex if GC is not in progress, but not
297 // if GC is in progress (since the mutex is already held on its behalf.)
298
299 class GCMutexLocker: public StackObj {
300 private:
301 Monitor * _mutex;
302 bool _locked;
303 public:
304 GCMutexLocker(Monitor * mutex);
305 ~GCMutexLocker() { if (_locked) _mutex->unlock(); }
306 };
307
308
309
310 // A MutexUnlocker temporarily exits a previously
311 // entered mutex for the scope which contains the unlocker.
312
313 class MutexUnlocker: StackObj {
314 private:
315 Monitor * _mutex;
316
317 public:
318 MutexUnlocker(Monitor * mutex) {
319 _mutex = mutex;
320 _mutex->unlock();
321 }
322
323 ~MutexUnlocker() {
324 _mutex->lock();
325 }
326 };
327
328 // A MutexUnlockerEx temporarily exits a previously
329 // entered mutex for the scope which contains the unlocker.
330
331 class MutexUnlockerEx: StackObj {
332 private:
333 Monitor * _mutex;
334 bool _no_safepoint_check;
335
336 public:
337 MutexUnlockerEx(Monitor * mutex, bool no_safepoint_check = !Mutex::_no_safepoint_check_flag) {
338 _mutex = mutex;
339 _no_safepoint_check = no_safepoint_check;
340 _mutex->unlock();
341 }
342
343 ~MutexUnlockerEx() {
344 if (_no_safepoint_check == Mutex::_no_safepoint_check_flag) {
345 _mutex->lock_without_safepoint_check();
346 } else {
347 _mutex->lock();
348 }
349 }
350 };
351
352 #endif // SHARE_RUNTIME_MUTEXLOCKER_HPP