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.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "runtime/mutexLocker.hpp"
27 #include "runtime/os.inline.hpp"
28 #include "runtime/safepoint.hpp"
29 #include "runtime/thread.inline.hpp"
30 #include "runtime/vmThread.hpp"
31
32 // Mutexes used in the VM (see comment in mutexLocker.hpp):
33 //
34 // Note that the following pointers are effectively final -- after having been
35 // set at JVM startup-time, they should never be subsequently mutated.
36 // Instead of using pointers to malloc()ed monitors and mutexes we should consider
37 // eliminating the indirection and using instances instead.
38 // Consider using GCC's __read_mostly.
39
40 Mutex* Patching_lock = NULL;
41 Monitor* SystemDictionary_lock = NULL;
42 Mutex* ProtectionDomainSet_lock = NULL;
43 Mutex* SharedDictionary_lock = NULL;
44 Mutex* Module_lock = NULL;
45 Mutex* CompiledIC_lock = NULL;
46 Mutex* InlineCacheBuffer_lock = NULL;
47 Mutex* VMStatistic_lock = NULL;
48 Mutex* JNIGlobalAlloc_lock = NULL;
49 Mutex* JNIGlobalActive_lock = NULL;
50 Mutex* JNIWeakAlloc_lock = NULL;
51 Mutex* JNIWeakActive_lock = NULL;
52 Mutex* StringTableWeakAlloc_lock = NULL;
53 Mutex* StringTableWeakActive_lock = NULL;
54 Mutex* JNIHandleBlockFreeList_lock = NULL;
55 Mutex* VMWeakAlloc_lock = NULL;
56 Mutex* VMWeakActive_lock = NULL;
57 Mutex* ResolvedMethodTableWeakAlloc_lock = NULL;
58 Mutex* ResolvedMethodTableWeakActive_lock = NULL;
59 Mutex* JmethodIdCreation_lock = NULL;
60 Mutex* JfieldIdCreation_lock = NULL;
61 Monitor* JNICritical_lock = NULL;
62 Mutex* JvmtiThreadState_lock = NULL;
63 Monitor* Heap_lock = NULL;
64 Mutex* ExpandHeap_lock = NULL;
65 Mutex* AdapterHandlerLibrary_lock = NULL;
66 Mutex* SignatureHandlerLibrary_lock = NULL;
67 Mutex* VtableStubs_lock = NULL;
68 Mutex* SymbolArena_lock = NULL;
69 Monitor* StringDedupQueue_lock = NULL;
70 Mutex* StringDedupTable_lock = NULL;
71 Monitor* CodeCache_lock = NULL;
72 Mutex* MethodData_lock = NULL;
73 Mutex* TouchedMethodLog_lock = NULL;
74 Mutex* RetData_lock = NULL;
75 Monitor* VMOperationQueue_lock = NULL;
76 Monitor* VMOperationRequest_lock = NULL;
77 Monitor* SerializePage_lock = NULL;
78 Monitor* Threads_lock = NULL;
79 Mutex* NonJavaThreadsList_lock = NULL;
80 Mutex* NonJavaThreadsListSync_lock = NULL;
81 Monitor* CGC_lock = NULL;
82 Monitor* STS_lock = NULL;
83 Monitor* FullGCCount_lock = NULL;
84 Monitor* SATB_Q_CBL_mon = NULL;
85 Monitor* DirtyCardQ_CBL_mon = NULL;
86 Mutex* Shared_DirtyCardQ_lock = NULL;
87 Mutex* MarkStackFreeList_lock = NULL;
88 Mutex* MarkStackChunkList_lock = NULL;
89 Mutex* MonitoringSupport_lock = NULL;
90 Mutex* ParGCRareEvent_lock = NULL;
91 Mutex* DerivedPointerTableGC_lock = NULL;
92 Monitor* CGCPhaseManager_lock = NULL;
93 Mutex* Compile_lock = NULL;
94 Monitor* MethodCompileQueue_lock = NULL;
95 Monitor* CompileThread_lock = NULL;
96 Monitor* Compilation_lock = NULL;
97 Mutex* CompileTaskAlloc_lock = NULL;
98 Mutex* CompileStatistics_lock = NULL;
99 Mutex* DirectivesStack_lock = NULL;
100 Mutex* MultiArray_lock = NULL;
101 Monitor* Terminator_lock = NULL;
102 Monitor* InitCompleted_lock = NULL;
103 Monitor* BeforeExit_lock = NULL;
104 Monitor* Notify_lock = NULL;
105 Mutex* ProfilePrint_lock = NULL;
106 Mutex* ExceptionCache_lock = NULL;
107 Mutex* OsrList_lock = NULL;
108 Mutex* NMethodSweeperStats_lock = NULL;
109 #ifndef PRODUCT
110 Mutex* FullGCALot_lock = NULL;
111 #endif
112
113 Mutex* Debug1_lock = NULL;
114 Mutex* Debug2_lock = NULL;
115 Mutex* Debug3_lock = NULL;
116
117 Mutex* tty_lock = NULL;
118
119 Mutex* RawMonitor_lock = NULL;
120 Mutex* PerfDataMemAlloc_lock = NULL;
121 Mutex* PerfDataManager_lock = NULL;
122 Mutex* OopMapCacheAlloc_lock = NULL;
123
124 Mutex* FreeList_lock = NULL;
125 Mutex* OldSets_lock = NULL;
126 Monitor* RootRegionScan_lock = NULL;
127
128 Monitor* GCTaskManager_lock = NULL;
129
130 Mutex* Management_lock = NULL;
131 Monitor* Service_lock = NULL;
132 Monitor* PeriodicTask_lock = NULL;
133 Monitor* RedefineClasses_lock = NULL;
134
135 #if INCLUDE_JFR
136 Mutex* JfrStacktrace_lock = NULL;
137 Monitor* JfrMsg_lock = NULL;
138 Mutex* JfrBuffer_lock = NULL;
139 Mutex* JfrStream_lock = NULL;
140 Monitor* JfrThreadSampler_lock = NULL;
141 #endif
142
143 #ifndef SUPPORTS_NATIVE_CX8
144 Mutex* UnsafeJlong_lock = NULL;
145 #endif
146 Monitor* CodeHeapStateAnalytics_lock = NULL;
147
148 Mutex* MetaspaceExpand_lock = NULL;
149 Mutex* ClassLoaderDataGraph_lock = NULL;
150 Monitor* ThreadsSMRDelete_lock = NULL;
151 Mutex* SharedDecoder_lock = NULL;
152 Mutex* DCmdFactory_lock = NULL;
153 #if INCLUDE_NMT
154 Mutex* NMTQuery_lock = NULL;
155 #endif
156 #if INCLUDE_CDS && INCLUDE_JVMTI
157 Mutex* CDSClassFileStream_lock = NULL;
158 #endif
159
160 #define MAX_NUM_MUTEX 128
161 static Monitor * _mutex_array[MAX_NUM_MUTEX];
162 static int _num_mutex;
163
164 #ifdef ASSERT
165 void assert_locked_or_safepoint(const Monitor * lock) {
166 // check if this thread owns the lock (common case)
167 if (IgnoreLockingAssertions) return;
168 assert(lock != NULL, "Need non-NULL lock");
169 if (lock->owned_by_self()) return;
170 if (SafepointSynchronize::is_at_safepoint()) return;
171 if (!Universe::is_fully_initialized()) return;
172 // see if invoker of VM operation owns it
173 VM_Operation* op = VMThread::vm_operation();
174 if (op != NULL && op->calling_thread() == lock->owner()) return;
175 fatal("must own lock %s", lock->name());
176 }
177
178 // a weaker assertion than the above
179 void assert_locked_or_safepoint_weak(const Monitor * lock) {
180 if (IgnoreLockingAssertions) return;
181 assert(lock != NULL, "Need non-NULL lock");
182 if (lock->is_locked()) return;
183 if (SafepointSynchronize::is_at_safepoint()) return;
184 if (!Universe::is_fully_initialized()) return;
185 fatal("must own lock %s", lock->name());
186 }
187
188 // a stronger assertion than the above
189 void assert_lock_strong(const Monitor * lock) {
190 if (IgnoreLockingAssertions) return;
191 assert(lock != NULL, "Need non-NULL lock");
192 if (lock->owned_by_self()) return;
193 fatal("must own lock %s", lock->name());
194 }
195 #endif
196
197 #define def(var, type, pri, vm_block, safepoint_check_allowed ) { \
198 var = new type(Mutex::pri, #var, vm_block, safepoint_check_allowed); \
199 assert(_num_mutex < MAX_NUM_MUTEX, "increase MAX_NUM_MUTEX"); \
200 _mutex_array[_num_mutex++] = var; \
201 }
202
203 // Using Padded subclasses to prevent false sharing of these global monitors and mutexes.
204 void mutex_init() {
205 def(tty_lock , PaddedMutex , tty, true, Monitor::_safepoint_check_never); // allow to lock in VM
206
207 def(CGC_lock , PaddedMonitor, special, true, Monitor::_safepoint_check_never); // coordinate between fore- and background GC
208 def(STS_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never);
209
210 def(VMWeakAlloc_lock , PaddedMutex , vmweak, true, Monitor::_safepoint_check_never);
211 def(VMWeakActive_lock , PaddedMutex , vmweak-1, true, Monitor::_safepoint_check_never);
212
213 def(StringTableWeakAlloc_lock , PaddedMutex , vmweak, true, Monitor::_safepoint_check_never);
214 def(StringTableWeakActive_lock , PaddedMutex , vmweak-1, true, Monitor::_safepoint_check_never);
215
216 def(ResolvedMethodTableWeakAlloc_lock , PaddedMutex , vmweak, true, Monitor::_safepoint_check_never);
217 def(ResolvedMethodTableWeakActive_lock , PaddedMutex , vmweak-1, true, Monitor::_safepoint_check_never);
218
219 if (UseConcMarkSweepGC || UseG1GC) {
220 def(FullGCCount_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never); // in support of ExplicitGCInvokesConcurrent
221 }
222 if (UseG1GC) {
223 def(SATB_Q_CBL_mon , PaddedMonitor, access, true, Monitor::_safepoint_check_never);
224
225 def(DirtyCardQ_CBL_mon , PaddedMonitor, access, true, Monitor::_safepoint_check_never);
226 def(Shared_DirtyCardQ_lock , PaddedMutex , access + 1, true, Monitor::_safepoint_check_never);
227
228 def(FreeList_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never);
229 def(OldSets_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never);
230 def(RootRegionScan_lock , PaddedMonitor, leaf , true, Monitor::_safepoint_check_never);
231
232 def(StringDedupQueue_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never);
233 def(StringDedupTable_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never);
234
235 def(MarkStackFreeList_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never);
236 def(MarkStackChunkList_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never);
237
238 def(MonitoringSupport_lock , PaddedMutex , native , true, Monitor::_safepoint_check_never); // used for serviceability monitoring support
239 }
240 if (UseShenandoahGC) {
241 def(SATB_Q_CBL_mon , PaddedMonitor, access, true, Monitor::_safepoint_check_never);
242
243 def(StringDedupQueue_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never);
244 def(StringDedupTable_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never);
245 }
246 def(ParGCRareEvent_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_sometimes);
247 def(DerivedPointerTableGC_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never);
248 def(CGCPhaseManager_lock , PaddedMonitor, leaf, false, Monitor::_safepoint_check_sometimes);
249 def(CodeCache_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never);
250 def(RawMonitor_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never);
251 def(OopMapCacheAlloc_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for oop_map_cache allocation.
252
253 def(MetaspaceExpand_lock , PaddedMutex , leaf-1, true, Monitor::_safepoint_check_never);
254 def(ClassLoaderDataGraph_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_always);
255
256 def(Patching_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); // used for safepointing and code patching.
257 def(Service_lock , PaddedMonitor, special, true, Monitor::_safepoint_check_never); // used for service thread operations
258 def(JmethodIdCreation_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for creating jmethodIDs.
259
260 def(SystemDictionary_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_always); // lookups done by VM thread
261 def(ProtectionDomainSet_lock , PaddedMutex , leaf-1, true, Monitor::_safepoint_check_never);
262 def(SharedDictionary_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // lookups done by VM thread
263 def(Module_lock , PaddedMutex , leaf+2, true, Monitor::_safepoint_check_always);
264 def(InlineCacheBuffer_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never);
265 def(VMStatistic_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always);
266 def(ExpandHeap_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // Used during compilation by VM thread
267 def(JNIHandleBlockFreeList_lock , PaddedMutex , leaf-1, true, Monitor::_safepoint_check_never); // handles are used by VM thread
268 def(SignatureHandlerLibrary_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always);
269 def(SymbolArena_lock , PaddedMutex , leaf+2, true, Monitor::_safepoint_check_never);
270 def(ProfilePrint_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); // serial profile printing
271 def(ExceptionCache_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); // serial profile printing
272 def(OsrList_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never);
273 def(Debug1_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never);
274 #ifndef PRODUCT
275 def(FullGCALot_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); // a lock to make FullGCALot MT safe
276 #endif
277 def(BeforeExit_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_always);
278 def(PerfDataMemAlloc_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for allocating PerfData memory for performance data
279 def(PerfDataManager_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for synchronized access to PerfDataManager resources
280
281 // CMS_modUnionTable_lock leaf
282 // CMS_bitMap_lock leaf 1
283 // CMS_freeList_lock leaf 2
284
285 def(Threads_lock , PaddedMonitor, barrier, true, Monitor::_safepoint_check_sometimes);
286 def(NonJavaThreadsList_lock , PaddedMutex, leaf, true, Monitor::_safepoint_check_never);
287 def(NonJavaThreadsListSync_lock , PaddedMutex, leaf, true, Monitor::_safepoint_check_never);
288
289 def(VMOperationQueue_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_sometimes); // VM_thread allowed to block on these
290 def(VMOperationRequest_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_sometimes);
291 def(RetData_lock , PaddedMutex , nonleaf, false, Monitor::_safepoint_check_always);
292 def(Terminator_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_sometimes);
293 def(InitCompleted_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never);
294 def(VtableStubs_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_never);
295 def(Notify_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_always);
296 def(JNIGlobalAlloc_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_never);
297 def(JNIGlobalActive_lock , PaddedMutex , nonleaf-1, true, Monitor::_safepoint_check_never);
298 def(JNIWeakAlloc_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_never);
299 def(JNIWeakActive_lock , PaddedMutex , nonleaf-1, true, Monitor::_safepoint_check_never);
300 def(JNICritical_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_always); // used for JNI critical regions
301 def(AdapterHandlerLibrary_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_always);
302
303 def(Heap_lock , PaddedMonitor, nonleaf+1, false, Monitor::_safepoint_check_sometimes);
304 def(JfieldIdCreation_lock , PaddedMutex , nonleaf+1, true, Monitor::_safepoint_check_always); // jfieldID, Used in VM_Operation
305
306 def(CompiledIC_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_never); // locks VtableStubs_lock, InlineCacheBuffer_lock
307 def(CompileTaskAlloc_lock , PaddedMutex , nonleaf+2, true, Monitor::_safepoint_check_always);
308 def(CompileStatistics_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always);
309 def(DirectivesStack_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never);
310 def(MultiArray_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always);
311
312 def(JvmtiThreadState_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); // Used by JvmtiThreadState/JvmtiEventController
313 def(Management_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); // used for JVM management
314
315 def(Compile_lock , PaddedMutex , nonleaf+3, true, Monitor::_safepoint_check_always);
316 def(MethodData_lock , PaddedMutex , nonleaf+3, false, Monitor::_safepoint_check_always);
317 def(TouchedMethodLog_lock , PaddedMutex , nonleaf+3, false, Monitor::_safepoint_check_always);
318
319 def(MethodCompileQueue_lock , PaddedMonitor, nonleaf+4, true, Monitor::_safepoint_check_always);
320 def(Debug2_lock , PaddedMutex , nonleaf+4, true, Monitor::_safepoint_check_never);
321 def(Debug3_lock , PaddedMutex , nonleaf+4, true, Monitor::_safepoint_check_never);
322 def(CompileThread_lock , PaddedMonitor, nonleaf+5, false, Monitor::_safepoint_check_always);
323 def(PeriodicTask_lock , PaddedMonitor, nonleaf+5, true, Monitor::_safepoint_check_sometimes);
324 def(RedefineClasses_lock , PaddedMonitor, nonleaf+5, true, Monitor::_safepoint_check_always);
325
326 if (WhiteBoxAPI) {
327 def(Compilation_lock , PaddedMonitor, leaf, false, Monitor::_safepoint_check_never);
328 }
329
330 #if INCLUDE_JFR
331 def(JfrMsg_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_always);
332 def(JfrBuffer_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never);
333 def(JfrStream_lock , PaddedMutex , leaf+1, true, Monitor::_safepoint_check_never); // ensure to rank lower than 'safepoint'
334 def(JfrStacktrace_lock , PaddedMutex , special, true, Monitor::_safepoint_check_sometimes);
335 def(JfrThreadSampler_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never);
336 #endif
337
338 #ifndef SUPPORTS_NATIVE_CX8
339 def(UnsafeJlong_lock , PaddedMutex , special, false, Monitor::_safepoint_check_never);
340 #endif
341
342 def(CodeHeapStateAnalytics_lock , PaddedMutex , nonleaf+6, true, Monitor::_safepoint_check_never);
343
344 def(NMethodSweeperStats_lock , PaddedMutex , special, true, Monitor::_safepoint_check_sometimes);
345 def(ThreadsSMRDelete_lock , PaddedMonitor, special, false, Monitor::_safepoint_check_never);
346 def(SharedDecoder_lock , PaddedMutex , native, false, Monitor::_safepoint_check_never);
347 def(DCmdFactory_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never);
348 #if INCLUDE_NMT
349 def(NMTQuery_lock , PaddedMutex , max_nonleaf, false, Monitor::_safepoint_check_always);
350 #endif
351 #if INCLUDE_CDS && INCLUDE_JVMTI
352 def(CDSClassFileStream_lock , PaddedMutex , max_nonleaf, false, Monitor::_safepoint_check_always);
353 #endif
354 }
355
356 GCMutexLocker::GCMutexLocker(Monitor * mutex) {
357 if (SafepointSynchronize::is_at_safepoint()) {
358 _locked = false;
359 } else {
360 _mutex = mutex;
361 _locked = true;
362 _mutex->lock();
363 }
364 }
365
366 // Print all mutexes/monitors that are currently owned by a thread; called
367 // by fatal error handler.
368 void print_owned_locks_on_error(outputStream* st) {
369 st->print("VM Mutex/Monitor currently owned by a thread: ");
370 bool none = true;
371 for (int i = 0; i < _num_mutex; i++) {
372 // see if it has an owner
373 if (_mutex_array[i]->owner() != NULL) {
374 if (none) {
375 // print format used by Mutex::print_on_error()
376 st->print_cr(" ([mutex/lock_event])");
377 none = false;
378 }
379 _mutex_array[i]->print_on_error(st);
380 st->cr();
381 }
382 }
383 if (none) st->print_cr("None");
384 }