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.
22 *
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* NMethodState_lock; // a lock used to guard a compiled method state
36 extern Monitor* SystemDictionary_lock; // a lock on the system dictionary
37 extern Mutex* InvokeMethodTypeTable_lock;
38 extern Monitor* InvokeMethodIntrinsicTable_lock;
39 extern Mutex* SharedDictionary_lock; // a lock on the CDS shared dictionary
40 extern Monitor* ClassInitError_lock; // a lock on the class initialization error table
41 extern Mutex* Module_lock; // a lock on module and package related data structures
42 extern Mutex* CompiledIC_lock; // a lock used to guard compiled IC patching and access
43 extern Mutex* InlineCacheBuffer_lock; // a lock used to guard the InlineCacheBuffer
44 extern Mutex* VMStatistic_lock; // a lock used to guard statistics count increment
45 extern Mutex* JmethodIdCreation_lock; // a lock on creating JNI method identifiers
46 extern Mutex* JfieldIdCreation_lock; // a lock on creating JNI static field identifiers
47 extern Monitor* JNICritical_lock; // a lock used while entering and exiting JNI critical regions, allows GC to sometimes get in
48 extern Mutex* JvmtiThreadState_lock; // a lock on modification of JVMTI thread data
49 extern Monitor* EscapeBarrier_lock; // a lock to sync reallocating and relocking objects because of JVMTI access
50 extern Monitor* JvmtiVTMSTransition_lock; // a lock for Virtual Thread Mount State transition (VTMS transition) management
61 extern Monitor* CodeCache_lock; // a lock on the CodeCache
62 extern Mutex* TouchedMethodLog_lock; // a lock on allocation of LogExecutedMethods info
63 extern Mutex* RetData_lock; // a lock on installation of RetData inside method data
64 extern Monitor* VMOperation_lock; // a lock on queue of vm_operations waiting to execute
65 extern Monitor* Threads_lock; // a lock on the Threads table of active Java threads
66 // (also used by Safepoints too to block threads creation/destruction)
67 extern Mutex* NonJavaThreadsList_lock; // a lock on the NonJavaThreads list
68 extern Mutex* NonJavaThreadsListSync_lock; // a lock for NonJavaThreads list synchronization
69 extern Monitor* CGC_lock; // used for coordination between
70 // fore- & background GC threads.
71 extern Monitor* STS_lock; // used for joining/leaving SuspendibleThreadSet.
72 extern Monitor* G1OldGCCount_lock; // in support of "concurrent" full gc
73 extern Mutex* G1RareEvent_lock; // Synchronizes (rare) parallel GC operations.
74 extern Mutex* G1DetachedRefinementStats_lock; // Lock protecting detached refinement stats
75 extern Mutex* MarkStackFreeList_lock; // Protects access to the global mark stack free list.
76 extern Mutex* MarkStackChunkList_lock; // Protects access to the global mark stack chunk list.
77 extern Mutex* MonitoringSupport_lock; // Protects updates to the serviceability memory pools and allocated memory high water mark.
78 extern Monitor* ConcurrentGCBreakpoints_lock; // Protects concurrent GC breakpoint management
79 extern Mutex* Compile_lock; // a lock held when Compilation is updating code (used to block CodeCache traversal, CHA updates, etc)
80 extern Monitor* MethodCompileQueue_lock; // a lock held when method compilations are enqueued, dequeued
81 extern Monitor* CompileThread_lock; // a lock held by compile threads during compilation system initialization
82 extern Monitor* Compilation_lock; // a lock used to pause compilation
83 extern Mutex* CompileTaskAlloc_lock; // a lock held when CompileTasks are allocated
84 extern Mutex* CompileStatistics_lock; // a lock held when updating compilation statistics
85 extern Mutex* DirectivesStack_lock; // a lock held when mutating the dirstack and ref counting directives
86 extern Monitor* Terminator_lock; // a lock used to guard termination of the vm
87 extern Monitor* InitCompleted_lock; // a lock used to signal threads waiting on init completed
88 extern Monitor* BeforeExit_lock; // a lock used to guard cleanups and shutdown hooks
89 extern Monitor* Notify_lock; // a lock used to synchronize the start-up of the vm
90 extern Mutex* ExceptionCache_lock; // a lock used to synchronize exception cache updates
91
92 #ifndef PRODUCT
93 extern Mutex* FullGCALot_lock; // a lock to make FullGCALot MT safe
94 #endif // PRODUCT
95
96 extern Mutex* RawMonitor_lock;
97 extern Mutex* PerfDataMemAlloc_lock; // a lock on the allocator for PerfData memory for performance data
98 extern Mutex* PerfDataManager_lock; // a long on access to PerfDataManager resources
99
100 extern Mutex* FreeList_lock; // protects the free region list during safepoints
101 extern Mutex* OldSets_lock; // protects the old region sets
102 extern Mutex* Uncommit_lock; // protects the uncommit list when not at safepoints
109 extern Monitor* PeriodicTask_lock; // protects the periodic task structure
110 extern Monitor* RedefineClasses_lock; // locks classes from parallel redefinition
111 extern Mutex* Verify_lock; // synchronize initialization of verify library
112 extern Monitor* ThreadsSMRDelete_lock; // Used by ThreadsSMRSupport to take pressure off the Threads_lock
113 extern Mutex* ThreadIdTableCreate_lock; // Used by ThreadIdTable to lazily create the thread id table
114 extern Mutex* SharedDecoder_lock; // serializes access to the decoder during normal (not error reporting) use
115 extern Mutex* DCmdFactory_lock; // serialize access to DCmdFactory information
116 extern Mutex* NMTQuery_lock; // serialize NMT Dcmd queries
117 extern Mutex* NMTCompilationCostHistory_lock; // guards NMT compilation cost history
118 #if INCLUDE_CDS
119 #if INCLUDE_JVMTI
120 extern Mutex* CDSClassFileStream_lock; // FileMapInfo::open_stream_for_jvmti
121 #endif
122 extern Mutex* DumpTimeTable_lock; // SystemDictionaryShared::_dumptime_table
123 extern Mutex* CDSLambda_lock; // SystemDictionaryShared::get_shared_lambda_proxy_class
124 extern Mutex* DumpRegion_lock; // Symbol::operator new(size_t sz, int len)
125 extern Mutex* ClassListFile_lock; // ClassListWriter()
126 extern Mutex* UnregisteredClassesTable_lock; // UnregisteredClassesTableTable
127 extern Mutex* LambdaFormInvokers_lock; // Protecting LambdaFormInvokers::_lambdaform_lines
128 extern Mutex* ScratchObjects_lock; // Protecting _scratch_xxx_table in heapShared.cpp
129 #endif // INCLUDE_CDS
130 #if INCLUDE_JFR
131 extern Mutex* JfrStacktrace_lock; // used to guard access to the JFR stacktrace table
132 extern Monitor* JfrMsg_lock; // protects JFR messaging
133 extern Mutex* JfrBuffer_lock; // protects JFR buffer operations
134 extern Monitor* JfrThreadSampler_lock; // used to suspend/resume JFR thread sampler
135 #endif
136
137 extern Mutex* Metaspace_lock; // protects Metaspace virtualspace and chunk expansions
138 extern Monitor* MetaspaceCritical_lock; // synchronizes failed metaspace allocations that risk throwing metaspace OOM
139 extern Mutex* ClassLoaderDataGraph_lock; // protects CLDG list, needed for concurrent unloading
140
141
142 extern Mutex* CodeHeapStateAnalytics_lock; // lock print functions against concurrent analyze functions.
143 // Only used locally in PrintCodeCacheLayout processing.
144
145 extern Monitor* ContinuationRelativize_lock;
146
147 #if INCLUDE_JVMCI
148 extern Monitor* JVMCI_lock; // protects global JVMCI critical sections
169
170 // Print all mutexes/monitors that are currently owned by a thread; called
171 // by fatal error handler.
172 void print_owned_locks_on_error(outputStream* st);
173 void print_lock_ranks(outputStream* st);
174
175 // for debugging: check that we're already owning this lock (or are at a safepoint / handshake)
176 #ifdef ASSERT
177 void assert_locked_or_safepoint(const Mutex* lock);
178 void assert_lock_strong(const Mutex* lock);
179 #else
180 #define assert_locked_or_safepoint(lock)
181 #define assert_lock_strong(lock)
182 #endif
183
184 // Internal implementation. Skips on null Mutex.
185 // Subclasses enforce stronger invariants.
186 class MutexLockerImpl: public StackObj {
187 protected:
188 Mutex* _mutex;
189
190 MutexLockerImpl(Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
191 _mutex(mutex) {
192 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag;
193 if (_mutex != nullptr) {
194 if (no_safepoint_check) {
195 _mutex->lock_without_safepoint_check();
196 } else {
197 _mutex->lock();
198 }
199 }
200 }
201
202 MutexLockerImpl(Thread* thread, Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
203 _mutex(mutex) {
204 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag;
205 if (_mutex != nullptr) {
206 if (no_safepoint_check) {
207 _mutex->lock_without_safepoint_check(thread);
208 } else {
209 _mutex->lock(thread);
210 }
211 }
212 }
213
214 ~MutexLockerImpl() {
215 if (_mutex != nullptr) {
216 assert_lock_strong(_mutex);
217 _mutex->unlock();
218 }
219 }
220
221 public:
222 static void post_initialize();
223 };
224
225 // Simplest mutex locker.
226 // Does not allow null mutexes.
227 class MutexLocker: public MutexLockerImpl {
228 public:
229 MutexLocker(Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
230 MutexLockerImpl(mutex, flag) {
231 assert(mutex != nullptr, "null mutex not allowed");
232 }
233
234 MutexLocker(Thread* thread, Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
235 MutexLockerImpl(thread, mutex, flag) {
236 assert(mutex != nullptr, "null mutex not allowed");
237 }
238 };
239
240 // Conditional mutex locker.
241 // Like MutexLocker above, but only locks when condition is true.
242 class ConditionalMutexLocker: public MutexLockerImpl {
|
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.
22 *
23 */
24
25 #ifndef SHARE_RUNTIME_MUTEXLOCKER_HPP
26 #define SHARE_RUNTIME_MUTEXLOCKER_HPP
27
28 #include "logging/log.hpp"
29 #include "memory/allocation.hpp"
30 #include "runtime/flags/flagSetting.hpp"
31 #include "runtime/mutex.hpp"
32 #include "runtime/perfData.hpp"
33 #include "runtime/thread.hpp"
34
35 // Mutexes used in the VM.
36
37 extern Mutex* Patching_lock; // a lock used to guard code patching of compiled code
38 extern Mutex* NMethodState_lock; // a lock used to guard a compiled method state
39 extern Monitor* SystemDictionary_lock; // a lock on the system dictionary
40 extern Mutex* InvokeMethodTypeTable_lock;
41 extern Monitor* InvokeMethodIntrinsicTable_lock;
42 extern Mutex* SharedDictionary_lock; // a lock on the CDS shared dictionary
43 extern Monitor* ClassInitError_lock; // a lock on the class initialization error table
44 extern Mutex* Module_lock; // a lock on module and package related data structures
45 extern Mutex* CompiledIC_lock; // a lock used to guard compiled IC patching and access
46 extern Mutex* InlineCacheBuffer_lock; // a lock used to guard the InlineCacheBuffer
47 extern Mutex* VMStatistic_lock; // a lock used to guard statistics count increment
48 extern Mutex* JmethodIdCreation_lock; // a lock on creating JNI method identifiers
49 extern Mutex* JfieldIdCreation_lock; // a lock on creating JNI static field identifiers
50 extern Monitor* JNICritical_lock; // a lock used while entering and exiting JNI critical regions, allows GC to sometimes get in
51 extern Mutex* JvmtiThreadState_lock; // a lock on modification of JVMTI thread data
52 extern Monitor* EscapeBarrier_lock; // a lock to sync reallocating and relocking objects because of JVMTI access
53 extern Monitor* JvmtiVTMSTransition_lock; // a lock for Virtual Thread Mount State transition (VTMS transition) management
64 extern Monitor* CodeCache_lock; // a lock on the CodeCache
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 Monitor* VMOperation_lock; // a lock on queue of vm_operations waiting to execute
68 extern Monitor* Threads_lock; // a lock on the Threads table of active Java threads
69 // (also used by Safepoints too to block threads creation/destruction)
70 extern Mutex* NonJavaThreadsList_lock; // a lock on the NonJavaThreads list
71 extern Mutex* NonJavaThreadsListSync_lock; // a lock for NonJavaThreads list synchronization
72 extern Monitor* CGC_lock; // used for coordination between
73 // fore- & background GC threads.
74 extern Monitor* STS_lock; // used for joining/leaving SuspendibleThreadSet.
75 extern Monitor* G1OldGCCount_lock; // in support of "concurrent" full gc
76 extern Mutex* G1RareEvent_lock; // Synchronizes (rare) parallel GC operations.
77 extern Mutex* G1DetachedRefinementStats_lock; // Lock protecting detached refinement stats
78 extern Mutex* MarkStackFreeList_lock; // Protects access to the global mark stack free list.
79 extern Mutex* MarkStackChunkList_lock; // Protects access to the global mark stack chunk list.
80 extern Mutex* MonitoringSupport_lock; // Protects updates to the serviceability memory pools and allocated memory high water mark.
81 extern Monitor* ConcurrentGCBreakpoints_lock; // Protects concurrent GC breakpoint management
82 extern Mutex* Compile_lock; // a lock held when Compilation is updating code (used to block CodeCache traversal, CHA updates, etc)
83 extern Monitor* MethodCompileQueue_lock; // a lock held when method compilations are enqueued, dequeued
84 extern Monitor* MethodCompileQueueC1_lock; // a lock held when method compilations are enqueued, dequeued
85 extern Monitor* MethodCompileQueueC2_lock; // a lock held when method compilations are enqueued, dequeued
86 extern Monitor* MethodCompileQueueC3_lock; // a lock held when method compilations are enqueued, dequeued
87 extern Monitor* MethodCompileQueueSC1_lock; // a lock held when method compilations are enqueued, dequeued
88 extern Monitor* MethodCompileQueueSC2_lock; // a lock held when method compilations are enqueued, dequeued
89 extern Monitor* CompileThread_lock; // a lock held by compile threads during compilation system initialization
90 extern Monitor* Compilation_lock; // a lock used to pause compilation
91 extern Mutex* TrainingData_lock; // a lock used when accessing training records
92 extern Monitor* TrainingReplayQueue_lock; // a lock held when class are added/removed to the training replay queue
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 Monitor* Terminator_lock; // a lock used to guard termination of the vm
97 extern Monitor* InitCompleted_lock; // a lock used to signal threads waiting on init completed
98 extern Monitor* BeforeExit_lock; // a lock used to guard cleanups and shutdown hooks
99 extern Monitor* Notify_lock; // a lock used to synchronize the start-up of the vm
100 extern Mutex* ExceptionCache_lock; // a lock used to synchronize exception cache updates
101
102 #ifndef PRODUCT
103 extern Mutex* FullGCALot_lock; // a lock to make FullGCALot MT safe
104 #endif // PRODUCT
105
106 extern Mutex* RawMonitor_lock;
107 extern Mutex* PerfDataMemAlloc_lock; // a lock on the allocator for PerfData memory for performance data
108 extern Mutex* PerfDataManager_lock; // a long on access to PerfDataManager resources
109
110 extern Mutex* FreeList_lock; // protects the free region list during safepoints
111 extern Mutex* OldSets_lock; // protects the old region sets
112 extern Mutex* Uncommit_lock; // protects the uncommit list when not at safepoints
119 extern Monitor* PeriodicTask_lock; // protects the periodic task structure
120 extern Monitor* RedefineClasses_lock; // locks classes from parallel redefinition
121 extern Mutex* Verify_lock; // synchronize initialization of verify library
122 extern Monitor* ThreadsSMRDelete_lock; // Used by ThreadsSMRSupport to take pressure off the Threads_lock
123 extern Mutex* ThreadIdTableCreate_lock; // Used by ThreadIdTable to lazily create the thread id table
124 extern Mutex* SharedDecoder_lock; // serializes access to the decoder during normal (not error reporting) use
125 extern Mutex* DCmdFactory_lock; // serialize access to DCmdFactory information
126 extern Mutex* NMTQuery_lock; // serialize NMT Dcmd queries
127 extern Mutex* NMTCompilationCostHistory_lock; // guards NMT compilation cost history
128 #if INCLUDE_CDS
129 #if INCLUDE_JVMTI
130 extern Mutex* CDSClassFileStream_lock; // FileMapInfo::open_stream_for_jvmti
131 #endif
132 extern Mutex* DumpTimeTable_lock; // SystemDictionaryShared::_dumptime_table
133 extern Mutex* CDSLambda_lock; // SystemDictionaryShared::get_shared_lambda_proxy_class
134 extern Mutex* DumpRegion_lock; // Symbol::operator new(size_t sz, int len)
135 extern Mutex* ClassListFile_lock; // ClassListWriter()
136 extern Mutex* UnregisteredClassesTable_lock; // UnregisteredClassesTableTable
137 extern Mutex* LambdaFormInvokers_lock; // Protecting LambdaFormInvokers::_lambdaform_lines
138 extern Mutex* ScratchObjects_lock; // Protecting _scratch_xxx_table in heapShared.cpp
139 extern Mutex* ArchivedObjectTables_lock; // Protecting the table used by HeapShared::get_archived_object_permanent_index()
140 #endif // INCLUDE_CDS
141 #if INCLUDE_JFR
142 extern Mutex* JfrStacktrace_lock; // used to guard access to the JFR stacktrace table
143 extern Monitor* JfrMsg_lock; // protects JFR messaging
144 extern Mutex* JfrBuffer_lock; // protects JFR buffer operations
145 extern Monitor* JfrThreadSampler_lock; // used to suspend/resume JFR thread sampler
146 #endif
147
148 extern Mutex* Metaspace_lock; // protects Metaspace virtualspace and chunk expansions
149 extern Monitor* MetaspaceCritical_lock; // synchronizes failed metaspace allocations that risk throwing metaspace OOM
150 extern Mutex* ClassLoaderDataGraph_lock; // protects CLDG list, needed for concurrent unloading
151
152
153 extern Mutex* CodeHeapStateAnalytics_lock; // lock print functions against concurrent analyze functions.
154 // Only used locally in PrintCodeCacheLayout processing.
155
156 extern Monitor* ContinuationRelativize_lock;
157
158 #if INCLUDE_JVMCI
159 extern Monitor* JVMCI_lock; // protects global JVMCI critical sections
180
181 // Print all mutexes/monitors that are currently owned by a thread; called
182 // by fatal error handler.
183 void print_owned_locks_on_error(outputStream* st);
184 void print_lock_ranks(outputStream* st);
185
186 // for debugging: check that we're already owning this lock (or are at a safepoint / handshake)
187 #ifdef ASSERT
188 void assert_locked_or_safepoint(const Mutex* lock);
189 void assert_lock_strong(const Mutex* lock);
190 #else
191 #define assert_locked_or_safepoint(lock)
192 #define assert_lock_strong(lock)
193 #endif
194
195 // Internal implementation. Skips on null Mutex.
196 // Subclasses enforce stronger invariants.
197 class MutexLockerImpl: public StackObj {
198 protected:
199 Mutex* _mutex;
200 bool _prof;
201 elapsedTimer _before;
202 elapsedTimer _after;
203
204 private:
205 static PerfCounter** _perf_lock_count;
206 static PerfCounter** _perf_lock_wait_time;
207 static PerfCounter** _perf_lock_hold_time;
208
209 public:
210
211 MutexLockerImpl(Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
212 _mutex(mutex), _prof(ProfileVMLocks && Thread::current_or_null() != nullptr && Thread::current()->profile_vm_locks()) {
213
214 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag;
215 if (_mutex != nullptr) {
216 if (_prof) { _before.start(); } // before
217
218 if (no_safepoint_check) {
219 _mutex->lock_without_safepoint_check();
220 } else {
221 _mutex->lock();
222 }
223
224 if (_prof) { _before.stop(); _after.start(); } // after
225 }
226 }
227
228 MutexLockerImpl(Thread* thread, Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
229 _mutex(mutex), _prof(thread->profile_vm_locks()) {
230
231 if (_prof) { _before.start(); } // before
232
233 bool no_safepoint_check = flag == Mutex::_no_safepoint_check_flag;
234 if (_mutex != nullptr) {
235 if (no_safepoint_check) {
236 _mutex->lock_without_safepoint_check(thread);
237 } else {
238 _mutex->lock(thread);
239 }
240 }
241
242 if (_prof) { _before.stop(); _after.start(); } // after
243 }
244
245 ~MutexLockerImpl() {
246 if (_mutex != nullptr) {
247 assert_lock_strong(_mutex);
248 _mutex->unlock();
249
250 if (_mutex->id() == -1) {
251 log_trace(init)("Unnamed unclassified lock: %s", _mutex->name());
252 }
253
254 if (_prof) {
255 assert(UsePerfData, "required");
256 _after.stop();
257 _perf_lock_count [_mutex->id() + 1]->inc();
258 _perf_lock_wait_time[_mutex->id() + 1]->inc(_before.ticks());
259 _perf_lock_hold_time[_mutex->id() + 1]->inc(_after.ticks());
260 }
261 }
262 }
263
264 private:
265 static void print_counter_on(outputStream* st, const char* name, bool is_unique, int idx);
266
267 public:
268 static int name2id(const char* name);
269
270 static void post_initialize();
271 static void init_counters();
272 static void print_counters_on(outputStream* st);
273 };
274
275 // Simplest mutex locker.
276 // Does not allow null mutexes.
277 class MutexLocker: public MutexLockerImpl {
278 public:
279 MutexLocker(Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
280 MutexLockerImpl(mutex, flag) {
281 assert(mutex != nullptr, "null mutex not allowed");
282 }
283
284 MutexLocker(Thread* thread, Mutex* mutex, Mutex::SafepointCheckFlag flag = Mutex::_safepoint_check_flag) :
285 MutexLockerImpl(thread, mutex, flag) {
286 assert(mutex != nullptr, "null mutex not allowed");
287 }
288 };
289
290 // Conditional mutex locker.
291 // Like MutexLocker above, but only locks when condition is true.
292 class ConditionalMutexLocker: public MutexLockerImpl {
|