1 /*
2 * Copyright (c) 1997, 2017, 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* Module_lock = NULL;
43 Mutex* CompiledIC_lock = NULL;
44 Mutex* InlineCacheBuffer_lock = NULL;
45 Mutex* VMStatistic_lock = NULL;
46 Mutex* JNIGlobalHandle_lock = NULL;
47 Mutex* JNIHandleBlockFreeList_lock = NULL;
48 Mutex* MemberNameTable_lock = NULL;
49 Mutex* JmethodIdCreation_lock = NULL;
50 Mutex* JfieldIdCreation_lock = NULL;
51 Monitor* JNICritical_lock = NULL;
52 Mutex* JvmtiThreadState_lock = NULL;
53 Monitor* Heap_lock = NULL;
54 Mutex* ExpandHeap_lock = NULL;
55 Mutex* AdapterHandlerLibrary_lock = NULL;
56 Mutex* SignatureHandlerLibrary_lock = NULL;
57 Mutex* VtableStubs_lock = NULL;
58 Mutex* SymbolTable_lock = NULL;
59 Mutex* StringTable_lock = NULL;
60 Monitor* StringDedupQueue_lock = NULL;
61 Mutex* StringDedupTable_lock = NULL;
62 Monitor* CodeCache_lock = NULL;
63 Mutex* MethodData_lock = NULL;
64 Mutex* TouchedMethodLog_lock = NULL;
65 Mutex* RetData_lock = NULL;
66 Monitor* VMOperationQueue_lock = NULL;
67 Monitor* VMOperationRequest_lock = NULL;
68 Monitor* Safepoint_lock = NULL;
69 Monitor* SerializePage_lock = NULL;
70 Monitor* Threads_lock = NULL;
71 Monitor* CGC_lock = NULL;
72 Monitor* STS_lock = NULL;
73 Monitor* FullGCCount_lock = NULL;
74 Mutex* SATB_Q_FL_lock = NULL;
75 Monitor* SATB_Q_CBL_mon = NULL;
76 Mutex* Shared_SATB_Q_lock = NULL;
77 Mutex* DirtyCardQ_FL_lock = NULL;
78 Monitor* DirtyCardQ_CBL_mon = NULL;
79 Mutex* Shared_DirtyCardQ_lock = NULL;
80 Mutex* MarkStackFreeList_lock = NULL;
81 Mutex* MarkStackChunkList_lock = NULL;
82 Mutex* ParGCRareEvent_lock = NULL;
83 Mutex* DerivedPointerTableGC_lock = NULL;
84 Monitor* CGCPhaseManager_lock = NULL;
85 Mutex* Compile_lock = NULL;
86 Monitor* MethodCompileQueue_lock = NULL;
87 Monitor* CompileThread_lock = NULL;
88 Monitor* Compilation_lock = NULL;
89 Mutex* CompileTaskAlloc_lock = NULL;
90 Mutex* CompileStatistics_lock = NULL;
91 Mutex* DirectivesStack_lock = NULL;
92 Mutex* MultiArray_lock = NULL;
93 Monitor* Terminator_lock = NULL;
94 Monitor* BeforeExit_lock = NULL;
95 Monitor* Notify_lock = NULL;
96 Mutex* ProfilePrint_lock = NULL;
97 Mutex* ExceptionCache_lock = NULL;
98 Mutex* OsrList_lock = NULL;
99
100 #ifndef PRODUCT
101 Mutex* FullGCALot_lock = NULL;
102 #endif
103
104 Mutex* Debug1_lock = NULL;
105 Mutex* Debug2_lock = NULL;
106 Mutex* Debug3_lock = NULL;
107
108 Mutex* tty_lock = NULL;
109
110 Mutex* RawMonitor_lock = NULL;
111 Mutex* PerfDataMemAlloc_lock = NULL;
112 Mutex* PerfDataManager_lock = NULL;
113 Mutex* OopMapCacheAlloc_lock = NULL;
114
115 Mutex* FreeList_lock = NULL;
116 Monitor* SecondaryFreeList_lock = NULL;
117 Mutex* OldSets_lock = NULL;
118 Monitor* RootRegionScan_lock = NULL;
119 Mutex* MMUTracker_lock = NULL;
120
121 Monitor* GCTaskManager_lock = NULL;
122
123 Mutex* Management_lock = NULL;
124 Monitor* Service_lock = NULL;
125 Monitor* PeriodicTask_lock = NULL;
126 Monitor* RedefineClasses_lock = NULL;
127
128 #ifdef INCLUDE_TRACE
129 Mutex* JfrStacktrace_lock = NULL;
130 Monitor* JfrMsg_lock = NULL;
131 Mutex* JfrBuffer_lock = NULL;
132 Mutex* JfrStream_lock = NULL;
133 Mutex* JfrThreadGroups_lock = NULL;
134 #endif
135
136 #ifndef SUPPORTS_NATIVE_CX8
137 Mutex* UnsafeJlong_lock = NULL;
138 #endif
139
140 #define MAX_NUM_MUTEX 128
141 static Monitor * _mutex_array[MAX_NUM_MUTEX];
142 static int _num_mutex;
143
144 #ifdef ASSERT
145 void assert_locked_or_safepoint(const Monitor * lock) {
146 // check if this thread owns the lock (common case)
147 if (IgnoreLockingAssertions) return;
148 assert(lock != NULL, "Need non-NULL lock");
149 if (lock->owned_by_self()) return;
150 if (SafepointSynchronize::is_at_safepoint()) return;
151 if (!Universe::is_fully_initialized()) return;
152 // see if invoker of VM operation owns it
153 VM_Operation* op = VMThread::vm_operation();
154 if (op != NULL && op->calling_thread() == lock->owner()) return;
155 fatal("must own lock %s", lock->name());
156 }
157
158 // a stronger assertion than the above
159 void assert_lock_strong(const Monitor * lock) {
160 if (IgnoreLockingAssertions) return;
161 assert(lock != NULL, "Need non-NULL lock");
162 if (lock->owned_by_self()) return;
163 fatal("must own lock %s", lock->name());
164 }
165 #endif
166
167 #define def(var, type, pri, vm_block, safepoint_check_allowed ) { \
168 var = new type(Mutex::pri, #var, vm_block, safepoint_check_allowed); \
169 assert(_num_mutex < MAX_NUM_MUTEX, "increase MAX_NUM_MUTEX"); \
170 _mutex_array[_num_mutex++] = var; \
171 }
172
173 // Using Padded subclasses to prevent false sharing of these global monitors and mutexes.
174 void mutex_init() {
175 def(tty_lock , PaddedMutex , event, true, Monitor::_safepoint_check_never); // allow to lock in VM
176
177 def(CGC_lock , PaddedMonitor, special, true, Monitor::_safepoint_check_never); // coordinate between fore- and background GC
178 def(STS_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never);
179
180 if (UseConcMarkSweepGC || UseG1GC) {
181 def(FullGCCount_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never); // in support of ExplicitGCInvokesConcurrent
182 }
183 if (UseG1GC) {
184
185 def(SATB_Q_FL_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never);
186 def(SATB_Q_CBL_mon , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_never);
187 def(Shared_SATB_Q_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_never);
188
189 def(DirtyCardQ_FL_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never);
190 def(DirtyCardQ_CBL_mon , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_never);
191 def(Shared_DirtyCardQ_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_never);
192
193 def(FreeList_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never);
194 def(SecondaryFreeList_lock , PaddedMonitor, leaf , true, Monitor::_safepoint_check_never);
195 def(OldSets_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never);
196 def(RootRegionScan_lock , PaddedMonitor, leaf , true, Monitor::_safepoint_check_never);
197 def(MMUTracker_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never);
198
199 def(StringDedupQueue_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_never);
200 def(StringDedupTable_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never);
201
202 def(MarkStackFreeList_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never);
203 def(MarkStackChunkList_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_never);
204 }
205 def(ParGCRareEvent_lock , PaddedMutex , leaf , true, Monitor::_safepoint_check_sometimes);
206 def(DerivedPointerTableGC_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never);
207 #ifdef INCLUDE_ALL_GCS
208 def(CGCPhaseManager_lock , PaddedMonitor, leaf, false, Monitor::_safepoint_check_sometimes);
209 #endif
210 def(CodeCache_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never);
211 def(RawMonitor_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never);
212 def(OopMapCacheAlloc_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for oop_map_cache allocation.
213
214 def(Patching_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never); // used for safepointing and code patching.
215 def(Service_lock , PaddedMonitor, special, true, Monitor::_safepoint_check_never); // used for service thread operations
216 def(JmethodIdCreation_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for creating jmethodIDs.
217
218 def(SystemDictionary_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_always); // lookups done by VM thread
219 def(Module_lock , PaddedMutex , leaf+2, true, Monitor::_safepoint_check_always);
220 def(InlineCacheBuffer_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always);
221 def(VMStatistic_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always);
222 def(ExpandHeap_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // Used during compilation by VM thread
223 def(JNIHandleBlockFreeList_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never); // handles are used by VM thread
224 def(SignatureHandlerLibrary_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always);
225 def(SymbolTable_lock , PaddedMutex , leaf+2, true, Monitor::_safepoint_check_always);
226 def(StringTable_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always);
227 def(ProfilePrint_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); // serial profile printing
228 def(ExceptionCache_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); // serial profile printing
229 def(OsrList_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never);
230 def(Debug1_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never);
231 #ifndef PRODUCT
232 def(FullGCALot_lock , PaddedMutex , leaf, false, Monitor::_safepoint_check_always); // a lock to make FullGCALot MT safe
233 #endif
234 def(BeforeExit_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_always);
235 def(PerfDataMemAlloc_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for allocating PerfData memory for performance data
236 def(PerfDataManager_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always); // used for synchronized access to PerfDataManager resources
237
238 // CMS_modUnionTable_lock leaf
239 // CMS_bitMap_lock leaf 1
240 // CMS_freeList_lock leaf 2
241
242 def(Safepoint_lock , PaddedMonitor, safepoint, true, Monitor::_safepoint_check_sometimes); // locks SnippetCache_lock/Threads_lock
243
244 def(Threads_lock , PaddedMonitor, barrier, true, Monitor::_safepoint_check_sometimes);
245
246 def(VMOperationQueue_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_sometimes); // VM_thread allowed to block on these
247 def(VMOperationRequest_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_sometimes);
248 def(RetData_lock , PaddedMutex , nonleaf, false, Monitor::_safepoint_check_always);
249 def(Terminator_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_sometimes);
250 def(VtableStubs_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_always);
251 def(Notify_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_always);
252 def(JNIGlobalHandle_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_always); // locks JNIHandleBlockFreeList_lock
253 def(JNICritical_lock , PaddedMonitor, nonleaf, true, Monitor::_safepoint_check_always); // used for JNI critical regions
254 def(AdapterHandlerLibrary_lock , PaddedMutex , nonleaf, true, Monitor::_safepoint_check_always);
255
256 def(Heap_lock , PaddedMonitor, nonleaf+1, false, Monitor::_safepoint_check_sometimes);
257 def(JfieldIdCreation_lock , PaddedMutex , nonleaf+1, true, Monitor::_safepoint_check_always); // jfieldID, Used in VM_Operation
258 def(MemberNameTable_lock , PaddedMutex , nonleaf+1, false, Monitor::_safepoint_check_always); // Used to protect MemberNameTable
259
260 def(CompiledIC_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); // locks VtableStubs_lock, InlineCacheBuffer_lock
261 def(CompileTaskAlloc_lock , PaddedMutex , nonleaf+2, true, Monitor::_safepoint_check_always);
262 def(CompileStatistics_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always);
263 def(DirectivesStack_lock , PaddedMutex , special, true, Monitor::_safepoint_check_never);
264 def(MultiArray_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); // locks SymbolTable_lock
265
266 def(JvmtiThreadState_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); // Used by JvmtiThreadState/JvmtiEventController
267 def(Management_lock , PaddedMutex , nonleaf+2, false, Monitor::_safepoint_check_always); // used for JVM management
268
269 def(Compile_lock , PaddedMutex , nonleaf+3, true, Monitor::_safepoint_check_sometimes);
270 def(MethodData_lock , PaddedMutex , nonleaf+3, false, Monitor::_safepoint_check_always);
271 def(TouchedMethodLog_lock , PaddedMutex , nonleaf+3, false, Monitor::_safepoint_check_always);
272
273 def(MethodCompileQueue_lock , PaddedMonitor, nonleaf+4, true, Monitor::_safepoint_check_always);
274 def(Debug2_lock , PaddedMutex , nonleaf+4, true, Monitor::_safepoint_check_never);
275 def(Debug3_lock , PaddedMutex , nonleaf+4, true, Monitor::_safepoint_check_never);
276 def(CompileThread_lock , PaddedMonitor, nonleaf+5, false, Monitor::_safepoint_check_always);
277 def(PeriodicTask_lock , PaddedMonitor, nonleaf+5, true, Monitor::_safepoint_check_sometimes);
278 def(RedefineClasses_lock , PaddedMonitor, nonleaf+5, true, Monitor::_safepoint_check_always);
279 if (WhiteBoxAPI) {
280 def(Compilation_lock , PaddedMonitor, leaf, false, Monitor::_safepoint_check_never);
281 }
282
283 #ifdef INCLUDE_TRACE
284 def(JfrMsg_lock , PaddedMonitor, leaf, true, Monitor::_safepoint_check_always);
285 def(JfrBuffer_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_never);
286 def(JfrThreadGroups_lock , PaddedMutex , leaf, true, Monitor::_safepoint_check_always);
287 def(JfrStream_lock , PaddedMutex , leaf+1, true, Monitor::_safepoint_check_never); // ensure to rank lower than 'safepoint'
288 def(JfrStacktrace_lock , PaddedMutex , special, true, Monitor::_safepoint_check_sometimes);
289 #endif
290
291 #ifndef SUPPORTS_NATIVE_CX8
292 def(UnsafeJlong_lock , PaddedMutex , special, false, Monitor::_safepoint_check_never);
293 #endif
294 }
295
296 GCMutexLocker::GCMutexLocker(Monitor * mutex) {
297 if (SafepointSynchronize::is_at_safepoint()) {
298 _locked = false;
299 } else {
300 _mutex = mutex;
301 _locked = true;
302 _mutex->lock();
303 }
304 }
305
306 // Print all mutexes/monitors that are currently owned by a thread; called
307 // by fatal error handler.
308 void print_owned_locks_on_error(outputStream* st) {
309 st->print("VM Mutex/Monitor currently owned by a thread: ");
310 bool none = true;
311 for (int i = 0; i < _num_mutex; i++) {
312 // see if it has an owner
313 if (_mutex_array[i]->owner() != NULL) {
314 if (none) {
315 // print format used by Mutex::print_on_error()
316 st->print_cr(" ([mutex/lock_event])");
317 none = false;
318 }
319 _mutex_array[i]->print_on_error(st);
320 st->cr();
321 }
322 }
323 if (none) st->print_cr("None");
324 }