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