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.
18 *
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
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 #if INCLUDE_JVMCI
160 extern Monitor* JVMCI_lock; // Monitor to control initialization of JVMCI
161 extern Mutex* JVMCIGlobalAlloc_lock; // JVMCI global storage allocate list lock
162 extern Mutex* JVMCIGlobalActive_lock; // JVMCI global storage active list lock
163 #endif
164
165 // A MutexLocker provides mutual exclusion with respect to a given mutex
166 // for the scope which contains the locker. The lock is an OS lock, not
167 // an object lock, and the two do not interoperate. Do not use Mutex-based
168 // locks to lock on Java objects, because they will not be respected if a
169 // that object is locked using the Java locking mechanism.
170 //
171 // NOTE WELL!!
172 //
173 // See orderAccess.hpp. We assume throughout the VM that MutexLocker's
174 // and friends constructors do a fence, a lock and an acquire *in that
175 // order*. And that their destructors do a release and unlock, in *that*
176 // order. If their implementations change such that these assumptions
177 // are violated, a whole lot of code will break.
178
179 // Print all mutexes/monitors that are currently owned by a thread; called
180 // by fatal error handler.
181 void print_owned_locks_on_error(outputStream* st);
182
183 char *lock_name(Mutex *mutex);
184
185 // for debugging: check that we're already owning this lock (or are at a safepoint)
186 #ifdef ASSERT
187 void assert_locked_or_safepoint(const Monitor * lock);
188 void assert_locked_or_safepoint_weak(const Monitor * lock);
189 void assert_lock_strong(const Monitor * lock);
190 #else
191 #define assert_locked_or_safepoint(lock)
192 #define assert_locked_or_safepoint_weak(lock)
193 #define assert_lock_strong(lock)
194 #endif
195
196 class MutexLocker: public StackObj {
197 protected:
198 Monitor* _mutex;
199 private:
200 public:
201 MutexLocker(Monitor* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
202 _mutex(mutex) {
203 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag;
204 if (_mutex != NULL) {
205 assert(_mutex->rank() > Mutex::special || no_safepoint_check,
206 "Mutexes with rank special or lower should not do safepoint checks");
207 if (no_safepoint_check) {
208 _mutex->lock_without_safepoint_check();
209 } else {
210 _mutex->lock();
211 }
212 }
213 }
214
215 MutexLocker(Monitor* mutex, Thread* thread, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
216 _mutex(mutex) {
217 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag;
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(thread);
223 } else {
224 _mutex->lock(thread);
225 }
226 }
227 }
228
229 ~MutexLocker() {
230 if (_mutex != NULL) {
231 assert_lock_strong(_mutex);
232 _mutex->unlock();
233 }
234 }
235 };
236
237 // A MonitorLocker is like a MutexLocker above, except it allows
238 // wait/notify as well which are delegated to the underlying Monitor.
239 // It also disallows NULL.
240
241 class MonitorLocker: public MutexLocker {
242 Mutex::SafepointCheckFlag _flag;
243 public:
244 MonitorLocker(Monitor* monitor, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
245 MutexLocker(monitor, flag), _flag(flag) {
246 // Superclass constructor did locking
247 assert(_mutex != NULL, "NULL monitor not allowed");
248 }
249
250 MonitorLocker(Monitor* monitor, Thread* thread, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
251 MutexLocker(monitor, thread, flag), _flag(flag) {
252 // Superclass constructor did locking
253 assert(_mutex != NULL, "NULL monitor not allowed");
254 }
255
256 bool wait(long timeout = 0,
257 bool as_suspend_equivalent = !Mutex::_as_suspend_equivalent_flag) {
258 if (_flag == Mutex::_safepoint_check_flag) {
259 return _mutex->wait(timeout, as_suspend_equivalent);
260 } else {
261 return _mutex->wait_without_safepoint_check(timeout);
262 }
263 return false;
264 }
265
266 void notify_all() {
267 _mutex->notify_all();
268 }
269
270 void notify() {
271 _mutex->notify();
272 }
273 };
274
275
276 // A GCMutexLocker is usually initialized with a mutex that is
277 // automatically acquired in order to do GC. The function that
278 // synchronizes using a GCMutexLocker may be called both during and between
279 // GC's. Thus, it must acquire the mutex if GC is not in progress, but not
280 // if GC is in progress (since the mutex is already held on its behalf.)
281
282 class GCMutexLocker: public StackObj {
283 private:
284 Monitor* _mutex;
285 bool _locked;
286 public:
287 GCMutexLocker(Monitor* mutex);
288 ~GCMutexLocker() { if (_locked) _mutex->unlock(); }
289 };
290
291 // A MutexUnlocker temporarily exits a previously
292 // entered mutex for the scope which contains the unlocker.
293
294 class MutexUnlocker: StackObj {
295 private:
296 Monitor* _mutex;
297 bool _no_safepoint_check;
298
299 public:
300 MutexUnlocker(Monitor* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
301 _mutex(mutex),
302 _no_safepoint_check(flag) {
303 _mutex->unlock();
304 }
305
306 ~MutexUnlocker() {
307 if (_no_safepoint_check) {
308 _mutex->lock_without_safepoint_check();
309 } else {
310 _mutex->lock();
311 }
312 }
313 };
314
315 #endif // SHARE_RUNTIME_MUTEXLOCKER_HPP