1 /*
2 * Copyright (c) 1997, 2012, 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_VM_RUNTIME_MUTEXLOCKER_HPP
26 #define SHARE_VM_RUNTIME_MUTEXLOCKER_HPP
27
28 #include "memory/allocation.hpp"
29 #include "runtime/mutex.hpp"
30 #ifdef TARGET_OS_FAMILY_linux
31 # include "os_linux.inline.hpp"
32 #endif
33 #ifdef TARGET_OS_FAMILY_solaris
34 # include "os_solaris.inline.hpp"
35 #endif
36 #ifdef TARGET_OS_FAMILY_windows
37 # include "os_windows.inline.hpp"
38 #endif
39 #ifdef TARGET_OS_FAMILY_bsd
40 # include "os_bsd.inline.hpp"
41 #endif
42
43 // Mutexes used in the VM.
44
45 extern Mutex* Patching_lock; // a lock used to guard code patching of compiled code
46 extern Monitor* SystemDictionary_lock; // a lock on the system dictonary
47 extern Mutex* PackageTable_lock; // a lock on the class loader package table
48 extern Mutex* CompiledIC_lock; // a lock used to guard compiled IC patching and access
49 extern Mutex* InlineCacheBuffer_lock; // a lock used to guard the InlineCacheBuffer
50 extern Mutex* VMStatistic_lock; // a lock used to guard statistics count increment
51 extern Mutex* JNIGlobalHandle_lock; // a lock on creating JNI global handles
52 extern Mutex* JNIHandleBlockFreeList_lock; // a lock on the JNI handle block free list
53 extern Mutex* JNICachedItableIndex_lock; // a lock on caching an itable index during JNI invoke
54 extern Mutex* MemberNameTable_lock; // a lock on the MemberNameTable updates
55 extern Mutex* JmethodIdCreation_lock; // a lock on creating JNI method identifiers
56 extern Mutex* JfieldIdCreation_lock; // a lock on creating JNI static field identifiers
57 extern Monitor* JNICritical_lock; // a lock used while entering and exiting JNI critical regions, allows GC to sometimes get in
58 extern Mutex* JvmtiThreadState_lock; // a lock on modification of JVMTI thread data
59 extern Monitor* JvmtiPendingEvent_lock; // a lock on the JVMTI pending events list
60 extern Monitor* Heap_lock; // a lock on the heap
61 extern Mutex* ExpandHeap_lock; // a lock on expanding the heap
62 extern Mutex* AdapterHandlerLibrary_lock; // a lock on the AdapterHandlerLibrary
63 extern Mutex* SignatureHandlerLibrary_lock; // a lock on the SignatureHandlerLibrary
64 extern Mutex* VtableStubs_lock; // a lock on the VtableStubs
65 extern Mutex* SymbolTable_lock; // a lock on the symbol table
66 extern Mutex* StringTable_lock; // a lock on the interned string table
67 extern Mutex* CodeCache_lock; // a lock on the CodeCache, rank is special, use MutexLockerEx
68 extern Mutex* MethodData_lock; // a lock on installation of method data
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* VMOperationQueue_lock; // a lock on queue of vm_operations waiting to execute
72 extern Monitor* VMOperationRequest_lock; // a lock on Threads waiting for a vm_operation to terminate
73 extern Monitor* Safepoint_lock; // a lock used by the safepoint abstraction
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 Monitor* CGC_lock; // used for coordination between
77 // fore- & background GC threads.
78 extern Mutex* STS_init_lock; // coordinate initialization of SuspendibleThreadSets.
79 extern Monitor* SLT_lock; // used in CMS GC for acquiring PLL
80 extern Monitor* iCMS_lock; // CMS incremental mode start/stop notification
81 extern Monitor* FullGCCount_lock; // in support of "concurrent" full gc
82 extern Monitor* CMark_lock; // used for concurrent mark thread coordination
83 extern Mutex* CMRegionStack_lock; // used for protecting accesses to the CM region stack
84 extern Mutex* SATB_Q_FL_lock; // Protects SATB Q
85 // buffer free list.
86 extern Monitor* SATB_Q_CBL_mon; // Protects SATB Q
87 // completed buffer queue.
88 extern Mutex* Shared_SATB_Q_lock; // Lock protecting SATB
89 // queue shared by
90 // non-Java threads.
91
92 extern Mutex* DirtyCardQ_FL_lock; // Protects dirty card Q
93 // buffer free list.
94 extern Monitor* DirtyCardQ_CBL_mon; // Protects dirty card Q
95 // completed buffer queue.
96 extern Mutex* Shared_DirtyCardQ_lock; // Lock protecting dirty card
97 // queue shared by
98 // non-Java threads.
99 // (see option ExplicitGCInvokesConcurrent)
100 extern Mutex* ParGCRareEvent_lock; // Synchronizes various (rare) parallel GC ops.
101 extern Mutex* EvacFailureStack_lock; // guards the evac failure scan stack
102 extern Mutex* Compile_lock; // a lock held when Compilation is updating code (used to block CodeCache traversal, CHA updates, etc)
103 extern Monitor* MethodCompileQueue_lock; // a lock held when method compilations are enqueued, dequeued
104 extern Monitor* CompileThread_lock; // a lock held by compile threads during compilation system initialization
105 extern Mutex* CompileTaskAlloc_lock; // a lock held when CompileTasks are allocated
106 extern Mutex* CompileStatistics_lock; // a lock held when updating compilation statistics
107 extern Mutex* MultiArray_lock; // a lock used to guard allocation of multi-dim arrays
108 extern Monitor* Terminator_lock; // a lock used to guard termination of the vm
109 extern Monitor* BeforeExit_lock; // a lock used to guard cleanups and shutdown hooks
110 extern Monitor* Notify_lock; // a lock used to synchronize the start-up of the vm
111 extern Monitor* Interrupt_lock; // a lock used for condition variable mediated interrupt processing
112 extern Monitor* ProfileVM_lock; // a lock used for profiling the VMThread
113 extern Mutex* ProfilePrint_lock; // a lock used to serialize the printing of profiles
114 extern Mutex* ExceptionCache_lock; // a lock used to synchronize exception cache updates
115 extern Mutex* OsrList_lock; // a lock used to serialize access to OSR queues
116
117 #ifndef PRODUCT
118 extern Mutex* FullGCALot_lock; // a lock to make FullGCALot MT safe
119 #endif // PRODUCT
120 extern Mutex* Debug1_lock; // A bunch of pre-allocated locks that can be used for tracing
121 extern Mutex* Debug2_lock; // down synchronization related bugs!
122 extern Mutex* Debug3_lock;
123
124 extern Mutex* RawMonitor_lock;
125 extern Mutex* PerfDataMemAlloc_lock; // a lock on the allocator for PerfData memory for performance data
126 extern Mutex* PerfDataManager_lock; // a long on access to PerfDataManager resources
127 extern Mutex* ParkerFreeList_lock;
128 extern Mutex* OopMapCacheAlloc_lock; // protects allocation of oop_map caches
129
130 extern Mutex* FreeList_lock; // protects the free region list during safepoints
131 extern Monitor* SecondaryFreeList_lock; // protects the secondary free region list
132 extern Mutex* OldSets_lock; // protects the old region sets
133 extern Monitor* RootRegionScan_lock; // used to notify that the CM threads have finished scanning the IM snapshot regions
134 extern Mutex* MMUTracker_lock; // protects the MMU
135 // tracker data structures
136 extern Mutex* HotCardCache_lock; // protects the hot card cache
137
138 extern Mutex* Management_lock; // a lock used to serialize JVM management
139 extern Monitor* Service_lock; // a lock used for service thread operation
140 extern Monitor* PeriodicTask_lock; // protects the periodic task structure
141
142 #ifdef INCLUDE_TRACE
143 extern Mutex* JfrStacktrace_lock; // used to guard access to the JFR stacktrace table
144 extern Monitor* JfrMsg_lock; // protects JFR messaging
145 extern Mutex* JfrBuffer_lock; // protects JFR buffer operations
146 extern Mutex* JfrStream_lock; // protects JFR stream access
147 extern Mutex* JfrThreadGroups_lock; // protects JFR access to Thread Groups
148 #endif
149
150 // A MutexLocker provides mutual exclusion with respect to a given mutex
151 // for the scope which contains the locker. The lock is an OS lock, not
152 // an object lock, and the two do not interoperate. Do not use Mutex-based
153 // locks to lock on Java objects, because they will not be respected if a
154 // that object is locked using the Java locking mechanism.
155 //
156 // NOTE WELL!!
157 //
158 // See orderAccess.hpp. We assume throughout the VM that MutexLocker's
159 // and friends constructors do a fence, a lock and an acquire *in that
160 // order*. And that their destructors do a release and unlock, in *that*
161 // order. If their implementations change such that these assumptions
162 // are violated, a whole lot of code will break.
163
164 // Print all mutexes/monitors that are currently owned by a thread; called
165 // by fatal error handler.
166 void print_owned_locks_on_error(outputStream* st);
167
168 char *lock_name(Mutex *mutex);
169
170 class MutexLocker: StackObj {
171 private:
172 Monitor * _mutex;
173 public:
174 MutexLocker(Monitor * mutex) {
175 assert(mutex->rank() != Mutex::special,
176 "Special ranked mutex should only use MutexLockerEx");
177 _mutex = mutex;
178 _mutex->lock();
179 }
180
181 // Overloaded constructor passing current thread
182 MutexLocker(Monitor * mutex, Thread *thread) {
183 assert(mutex->rank() != Mutex::special,
184 "Special ranked mutex should only use MutexLockerEx");
185 _mutex = mutex;
186 _mutex->lock(thread);
187 }
188
189 ~MutexLocker() {
190 _mutex->unlock();
191 }
192
193 };
194
195 // for debugging: check that we're already owning this lock (or are at a safepoint)
196 #ifdef ASSERT
197 void assert_locked_or_safepoint(const Monitor * lock);
198 void assert_lock_strong(const Monitor * lock);
199 #else
200 #define assert_locked_or_safepoint(lock)
201 #define assert_lock_strong(lock)
202 #endif
203
204 // A MutexLockerEx behaves like a MutexLocker when its constructor is
205 // called with a Mutex. Unlike a MutexLocker, its constructor can also be
206 // called with NULL, in which case the MutexLockerEx is a no-op. There
207 // is also a corresponding MutexUnlockerEx. We want to keep the
208 // basic MutexLocker as fast as possible. MutexLockerEx can also lock
209 // without safepoint check.
210
211 class MutexLockerEx: public StackObj {
212 private:
213 Monitor * _mutex;
214 public:
215 MutexLockerEx(Monitor * mutex, bool no_safepoint_check = !Mutex::_no_safepoint_check_flag) {
216 _mutex = mutex;
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();
222 else
223 _mutex->lock();
224 }
225 }
226
227 ~MutexLockerEx() {
228 if (_mutex != NULL) {
229 _mutex->unlock();
230 }
231 }
232 };
233
234 // A MonitorLockerEx is like a MutexLockerEx above, except it takes
235 // a possibly null Monitor, and allows wait/notify as well which are
236 // delegated to the underlying Monitor.
237
238 class MonitorLockerEx: public MutexLockerEx {
239 private:
240 Monitor * _monitor;
241 public:
242 MonitorLockerEx(Monitor* monitor,
243 bool no_safepoint_check = !Mutex::_no_safepoint_check_flag):
244 MutexLockerEx(monitor, no_safepoint_check),
245 _monitor(monitor) {
246 // Superclass constructor did locking
247 }
248
249 ~MonitorLockerEx() {
250 #ifdef ASSERT
251 if (_monitor != NULL) {
252 assert_lock_strong(_monitor);
253 }
254 #endif // ASSERT
255 // Superclass destructor will do unlocking
256 }
257
258 bool wait(bool no_safepoint_check = !Mutex::_no_safepoint_check_flag,
259 long timeout = 0,
260 bool as_suspend_equivalent = !Mutex::_as_suspend_equivalent_flag) {
261 if (_monitor != NULL) {
262 return _monitor->wait(no_safepoint_check, timeout, as_suspend_equivalent);
263 }
264 return false;
265 }
266
267 bool notify_all() {
268 if (_monitor != NULL) {
269 return _monitor->notify_all();
270 }
271 return true;
272 }
273
274 bool notify() {
275 if (_monitor != NULL) {
276 return _monitor->notify();
277 }
278 return true;
279 }
280 };
281
282
283
284 // A GCMutexLocker is usually initialized with a mutex that is
285 // automatically acquired in order to do GC. The function that
286 // synchronizes using a GCMutexLocker may be called both during and between
287 // GC's. Thus, it must acquire the mutex if GC is not in progress, but not
288 // if GC is in progress (since the mutex is already held on its behalf.)
289
290 class GCMutexLocker: public StackObj {
291 private:
292 Monitor * _mutex;
293 bool _locked;
294 public:
295 GCMutexLocker(Monitor * mutex);
296 ~GCMutexLocker() { if (_locked) _mutex->unlock(); }
297 };
298
299
300
301 // A MutexUnlocker temporarily exits a previously
302 // entered mutex for the scope which contains the unlocker.
303
304 class MutexUnlocker: StackObj {
305 private:
306 Monitor * _mutex;
307
308 public:
309 MutexUnlocker(Monitor * mutex) {
310 _mutex = mutex;
311 _mutex->unlock();
312 }
313
314 ~MutexUnlocker() {
315 _mutex->lock();
316 }
317 };
318
319 // A MutexUnlockerEx temporarily exits a previously
320 // entered mutex for the scope which contains the unlocker.
321
322 class MutexUnlockerEx: StackObj {
323 private:
324 Monitor * _mutex;
325 bool _no_safepoint_check;
326
327 public:
328 MutexUnlockerEx(Monitor * mutex, bool no_safepoint_check = !Mutex::_no_safepoint_check_flag) {
329 _mutex = mutex;
330 _no_safepoint_check = no_safepoint_check;
331 _mutex->unlock();
332 }
333
334 ~MutexUnlockerEx() {
335 if (_no_safepoint_check == Mutex::_no_safepoint_check_flag) {
336 _mutex->lock_without_safepoint_check();
337 } else {
338 _mutex->lock();
339 }
340 }
341 };
342
343 #ifndef PRODUCT
344 //
345 // A special MutexLocker that allows:
346 // - reentrant locking
347 // - locking out of order
348 //
349 // Only too be used for verify code, where we can relaxe out dead-lock
350 // dection code a bit (unsafe, but probably ok). This code is NEVER to
351 // be included in a product version.
352 //
353 class VerifyMutexLocker: StackObj {
354 private:
355 Monitor * _mutex;
356 bool _reentrant;
357 public:
358 VerifyMutexLocker(Monitor * mutex) {
359 _mutex = mutex;
360 _reentrant = mutex->owned_by_self();
361 if (!_reentrant) {
362 // We temp. diable strict safepoint checking, while we require the lock
363 FlagSetting fs(StrictSafepointChecks, false);
364 _mutex->lock();
365 }
366 }
367
368 ~VerifyMutexLocker() {
369 if (!_reentrant) {
370 _mutex->unlock();
371 }
372 }
373 };
374
375 #endif
376
377 #endif // SHARE_VM_RUNTIME_MUTEXLOCKER_HPP