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 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* ResolvedMethodTableWeakAlloc_lock; // ResolvedMethodTable weak storage allocate list
52 extern Mutex* ResolvedMethodTableWeakActive_lock; // ResolvedMethodTable weak storage active list
53 extern Mutex* JmethodIdCreation_lock; // a lock on creating JNI method identifiers
54 extern Mutex* JfieldIdCreation_lock; // a lock on creating JNI static field identifiers
55 extern Monitor* JNICritical_lock; // a lock used while entering and exiting JNI critical regions, allows GC to sometimes get in
56 extern Mutex* JvmtiThreadState_lock; // a lock on modification of JVMTI thread data
57 extern Monitor* Heap_lock; // a lock on the heap
58 extern Mutex* ExpandHeap_lock; // a lock on expanding the heap
59 extern Mutex* AdapterHandlerLibrary_lock; // a lock on the AdapterHandlerLibrary
60 extern Mutex* SignatureHandlerLibrary_lock; // a lock on the SignatureHandlerLibrary
61 extern Mutex* VtableStubs_lock; // a lock on the VtableStubs
62 extern Mutex* SymbolArena_lock; // a lock on the symbol table arena
63 extern Monitor* StringDedupQueue_lock; // a lock on the string deduplication queue
64 extern Mutex* StringDedupTable_lock; // a lock on the string deduplication table
65 extern Monitor* CodeCache_lock; // a lock on the CodeCache, rank is special
66 extern Mutex* MethodData_lock; // a lock on installation of method data
67 extern Mutex* TouchedMethodLog_lock; // a lock on allocation of LogExecutedMethods info
68 extern Mutex* RetData_lock; // a lock on installation of RetData inside method data
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 Mutex* NonJavaThreadsListSync_lock; // a lock for NonJavaThreads list synchronization
76 extern Monitor* CGC_lock; // used for coordination between
77 // fore- & background GC threads.
78 extern Monitor* STS_lock; // used for joining/leaving SuspendibleThreadSet.
79 extern Monitor* FullGCCount_lock; // in support of "concurrent" full gc
80 extern Monitor* DirtyCardQ_CBL_mon; // Protects dirty card Q
81 // completed buffer queue.
82 extern Mutex* Shared_DirtyCardQ_lock; // Lock protecting dirty card
83 // queue shared by
84 // non-Java threads.
85 extern Mutex* MarkStackFreeList_lock; // Protects access to the global mark stack free list.
86 extern Mutex* MarkStackChunkList_lock; // Protects access to the global mark stack chunk list.
87 extern Mutex* MonitoringSupport_lock; // Protects updates to the serviceability memory pools.
88 extern Mutex* ParGCRareEvent_lock; // Synchronizes various (rare) parallel GC ops.
89 extern Mutex* Compile_lock; // a lock held when Compilation is updating code (used to block CodeCache traversal, CHA updates, etc)
90 extern Monitor* MethodCompileQueue_lock; // a lock held when method compilations are enqueued, dequeued
91 extern Monitor* CompileThread_lock; // a lock held by compile threads during compilation system initialization
92 extern Monitor* Compilation_lock; // a lock used to pause compilation
93 extern Mutex* CompileTaskAlloc_lock; // a lock held when CompileTasks are allocated
94 extern Mutex* CompileStatistics_lock; // a lock held when updating compilation statistics
95 extern Mutex* DirectivesStack_lock; // a lock held when mutating the dirstack and ref counting directives
96 extern Mutex* MultiArray_lock; // a lock used to guard allocation of multi-dim arrays
97 extern Monitor* Terminator_lock; // a lock used to guard termination of the vm
98 extern Monitor* InitCompleted_lock; // a lock used to signal threads waiting on init completed
99 extern Monitor* BeforeExit_lock; // a lock used to guard cleanups and shutdown hooks
100 extern Monitor* Notify_lock; // a lock used to synchronize the start-up of the vm
101 extern Mutex* ProfilePrint_lock; // a lock used to serialize the printing of profiles
102 extern Mutex* ExceptionCache_lock; // a lock used to synchronize exception cache updates
103 extern Mutex* OsrList_lock; // a lock used to serialize access to OSR queues
104 extern Mutex* NMethodSweeperStats_lock; // a lock used to serialize access to sweeper statistics
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 Monitor* ThreadsSMRDelete_lock; // Used by ThreadsSMRSupport to take pressure off the Threads_lock
128 extern Mutex* SharedDecoder_lock; // serializes access to the decoder during normal (not error reporting) use
129 extern Mutex* DCmdFactory_lock; // serialize access to DCmdFactory information
130 #if INCLUDE_NMT
131 extern Mutex* NMTQuery_lock; // serialize NMT Dcmd queries
132 #endif
133 #if INCLUDE_CDS
134 #if INCLUDE_JVMTI
135 extern Mutex* CDSClassFileStream_lock; // FileMapInfo::open_stream_for_jvmti
136 #endif
137 extern Mutex* DumpTimeTable_lock; // SystemDictionaryShared::find_or_allocate_info_for
138 #endif // INCLUDE_CDS
139 #if INCLUDE_JFR
140 extern Mutex* JfrStacktrace_lock; // used to guard access to the JFR stacktrace table
141 extern Monitor* JfrMsg_lock; // protects JFR messaging
142 extern Mutex* JfrBuffer_lock; // protects JFR buffer operations
143 extern Mutex* JfrStream_lock; // protects JFR stream access
144 extern Monitor* JfrThreadSampler_lock; // used to suspend/resume JFR thread sampler
145 #endif
146
147 #ifndef SUPPORTS_NATIVE_CX8
148 extern Mutex* UnsafeJlong_lock; // provides Unsafe atomic updates to jlongs on platforms that don't support cx8
149 #endif
150
151 extern Mutex* MetaspaceExpand_lock; // protects Metaspace virtualspace and chunk expansions
152 extern Mutex* ClassLoaderDataGraph_lock; // protects CLDG list, needed for concurrent unloading
153
154
155 extern Monitor* CodeHeapStateAnalytics_lock; // lock print functions against concurrent analyze functions.
156 // Only used locally in PrintCodeCacheLayout processing.
157
158 #if INCLUDE_JVMCI
159 extern Monitor* JVMCI_lock; // Monitor to control initialization of JVMCI
160 extern Mutex* JVMCIGlobalAlloc_lock; // JVMCI global storage allocate list lock
161 extern Mutex* JVMCIGlobalActive_lock; // JVMCI global storage active list lock
162 #endif
163
164 // A MutexLocker provides mutual exclusion with respect to a given mutex
165 // for the scope which contains the locker. The lock is an OS lock, not
166 // an object lock, and the two do not interoperate. Do not use Mutex-based
167 // locks to lock on Java objects, because they will not be respected if a
168 // that object is locked using the Java locking mechanism.
169 //
170 // NOTE WELL!!
171 //
172 // See orderAccess.hpp. We assume throughout the VM that MutexLocker's
173 // and friends constructors do a fence, a lock and an acquire *in that
174 // order*. And that their destructors do a release and unlock, in *that*
175 // order. If their implementations change such that these assumptions
176 // are violated, a whole lot of code will break.
177
178 // Print all mutexes/monitors that are currently owned by a thread; called
179 // by fatal error handler.
180 void print_owned_locks_on_error(outputStream* st);
181
182 char *lock_name(Mutex *mutex);
183
184 // for debugging: check that we're already owning this lock (or are at a safepoint)
185 #ifdef ASSERT
186 void assert_locked_or_safepoint(const Monitor * lock);
187 void assert_locked_or_safepoint_weak(const Monitor * lock);
188 void assert_lock_strong(const Monitor * lock);
189 #else
190 #define assert_locked_or_safepoint(lock)
191 #define assert_locked_or_safepoint_weak(lock)
192 #define assert_lock_strong(lock)
193 #endif
194
195 class MutexLocker: public StackObj {
196 protected:
197 Monitor* _mutex;
198 private:
199 public:
200 MutexLocker(Monitor* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
201 _mutex(mutex) {
202 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag;
203 if (_mutex != NULL) {
204 assert(_mutex->rank() > Mutex::special || no_safepoint_check,
205 "Mutexes with rank special or lower should not do safepoint checks");
206 if (no_safepoint_check) {
207 _mutex->lock_without_safepoint_check();
208 } else {
209 _mutex->lock();
210 }
211 }
212 }
213
214 MutexLocker(Monitor* mutex, Thread* thread, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
215 _mutex(mutex) {
216 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag;
217 if (_mutex != NULL) {
218 assert(_mutex->rank() > Mutex::special || no_safepoint_check,
219 "Mutexes with rank special or lower should not do safepoint checks");
220 if (no_safepoint_check) {
221 _mutex->lock_without_safepoint_check(thread);
222 } else {
223 _mutex->lock(thread);
224 }
225 }
226 }
227
228 ~MutexLocker() {
229 if (_mutex != NULL) {
230 assert_lock_strong(_mutex);
231 _mutex->unlock();
232 }
233 }
234 };
235
236 // A MonitorLocker is like a MutexLocker above, except it allows
237 // wait/notify as well which are delegated to the underlying Monitor.
238 // It also disallows NULL.
239
240 class MonitorLocker: public MutexLocker {
241 Mutex::SafepointCheckFlag _flag;
242 public:
243 MonitorLocker(Monitor* monitor, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
244 MutexLocker(monitor, flag), _flag(flag) {
245 // Superclass constructor did locking
246 assert(_mutex != NULL, "NULL monitor not allowed");
247 }
248
249 MonitorLocker(Monitor* monitor, Thread* thread, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
250 MutexLocker(monitor, thread, flag), _flag(flag) {
251 // Superclass constructor did locking
252 assert(_mutex != NULL, "NULL monitor not allowed");
253 }
254
255 bool wait(long timeout = 0,
256 bool as_suspend_equivalent = !Mutex::_as_suspend_equivalent_flag) {
257 if (_flag == Mutex::_safepoint_check_flag) {
258 return _mutex->wait(timeout, as_suspend_equivalent);
259 } else {
260 return _mutex->wait_without_safepoint_check(timeout);
261 }
262 return false;
263 }
264
265 void notify_all() {
266 _mutex->notify_all();
267 }
268
269 void notify() {
270 _mutex->notify();
271 }
272 };
273
274
275 // A GCMutexLocker is usually initialized with a mutex that is
276 // automatically acquired in order to do GC. The function that
277 // synchronizes using a GCMutexLocker may be called both during and between
278 // GC's. Thus, it must acquire the mutex if GC is not in progress, but not
279 // if GC is in progress (since the mutex is already held on its behalf.)
280
281 class GCMutexLocker: public StackObj {
282 private:
283 Monitor* _mutex;
284 bool _locked;
285 public:
286 GCMutexLocker(Monitor* mutex);
287 ~GCMutexLocker() { if (_locked) _mutex->unlock(); }
288 };
289
290 // A MutexUnlocker temporarily exits a previously
291 // entered mutex for the scope which contains the unlocker.
292
293 class MutexUnlocker: StackObj {
294 private:
295 Monitor* _mutex;
296 bool _no_safepoint_check;
297
298 public:
299 MutexUnlocker(Monitor* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
300 _mutex(mutex),
301 _no_safepoint_check(flag) {
302 _mutex->unlock();
303 }
304
305 ~MutexUnlocker() {
306 if (_no_safepoint_check) {
307 _mutex->lock_without_safepoint_check();
308 } else {
309 _mutex->lock();
310 }
311 }
312 };
313
314 #endif // SHARE_RUNTIME_MUTEXLOCKER_HPP