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