Wed, 02 Jun 2010 22:45:42 -0700
Merge
1 /*
2 * Copyright (c) 1997, 2009, 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 */
25 // Mutexes used in the VM.
27 extern Mutex* Patching_lock; // a lock used to guard code patching of compiled code
28 extern Monitor* SystemDictionary_lock; // a lock on the system dictonary
29 extern Mutex* PackageTable_lock; // a lock on the class loader package table
30 extern Mutex* CompiledIC_lock; // a lock used to guard compiled IC patching and access
31 extern Mutex* InlineCacheBuffer_lock; // a lock used to guard the InlineCacheBuffer
32 extern Mutex* VMStatistic_lock; // a lock used to guard statistics count increment
33 extern Mutex* JNIGlobalHandle_lock; // a lock on creating JNI global handles
34 extern Mutex* JNIHandleBlockFreeList_lock; // a lock on the JNI handle block free list
35 extern Mutex* JNICachedItableIndex_lock; // a lock on caching an itable index during JNI invoke
36 extern Mutex* JmethodIdCreation_lock; // a lock on creating JNI method identifiers
37 extern Mutex* JfieldIdCreation_lock; // a lock on creating JNI static field identifiers
38 extern Monitor* JNICritical_lock; // a lock used while entering and exiting JNI critical regions, allows GC to sometimes get in
39 extern Mutex* JvmtiThreadState_lock; // a lock on modification of JVMTI thread data
40 extern Monitor* JvmtiPendingEvent_lock; // a lock on the JVMTI pending events list
41 extern Monitor* Heap_lock; // a lock on the heap
42 extern Mutex* ExpandHeap_lock; // a lock on expanding the heap
43 extern Mutex* AdapterHandlerLibrary_lock; // a lock on the AdapterHandlerLibrary
44 extern Mutex* SignatureHandlerLibrary_lock; // a lock on the SignatureHandlerLibrary
45 extern Mutex* VtableStubs_lock; // a lock on the VtableStubs
46 extern Mutex* SymbolTable_lock; // a lock on the symbol table
47 extern Mutex* StringTable_lock; // a lock on the interned string table
48 extern Mutex* CodeCache_lock; // a lock on the CodeCache, rank is special, use MutexLockerEx
49 extern Mutex* MethodData_lock; // a lock on installation of method data
50 extern Mutex* RetData_lock; // a lock on installation of RetData inside method data
51 extern Mutex* DerivedPointerTableGC_lock; // a lock to protect the derived pointer table
52 extern Monitor* VMOperationQueue_lock; // a lock on queue of vm_operations waiting to execute
53 extern Monitor* VMOperationRequest_lock; // a lock on Threads waiting for a vm_operation to terminate
54 extern Monitor* Safepoint_lock; // a lock used by the safepoint abstraction
55 extern Monitor* Threads_lock; // a lock on the Threads table of active Java threads
56 // (also used by Safepoints too to block threads creation/destruction)
57 extern Monitor* CGC_lock; // used for coordination between
58 // fore- & background GC threads.
59 extern Mutex* STS_init_lock; // coordinate initialization of SuspendibleThreadSets.
60 extern Monitor* SLT_lock; // used in CMS GC for acquiring PLL
61 extern Monitor* iCMS_lock; // CMS incremental mode start/stop notification
62 extern Monitor* FullGCCount_lock; // in support of "concurrent" full gc
63 extern Monitor* CMark_lock; // used for concurrent mark thread coordination
64 extern Monitor* ZF_mon; // used for G1 conc zero-fill.
65 extern Monitor* Cleanup_mon; // used for G1 conc cleanup.
66 extern Mutex* CMRegionStack_lock; // used for protecting accesses to the CM region stack
67 extern Mutex* SATB_Q_FL_lock; // Protects SATB Q
68 // buffer free list.
69 extern Monitor* SATB_Q_CBL_mon; // Protects SATB Q
70 // completed buffer queue.
71 extern Mutex* Shared_SATB_Q_lock; // Lock protecting SATB
72 // queue shared by
73 // non-Java threads.
75 extern Mutex* DirtyCardQ_FL_lock; // Protects dirty card Q
76 // buffer free list.
77 extern Monitor* DirtyCardQ_CBL_mon; // Protects dirty card Q
78 // completed buffer queue.
79 extern Mutex* Shared_DirtyCardQ_lock; // Lock protecting dirty card
80 // queue shared by
81 // non-Java threads.
82 // (see option ExplicitGCInvokesConcurrent)
83 extern Mutex* ParGCRareEvent_lock; // Synchronizes various (rare) parallel GC ops.
84 extern Mutex* EvacFailureStack_lock; // guards the evac failure scan stack
85 extern Mutex* Compile_lock; // a lock held when Compilation is updating code (used to block CodeCache traversal, CHA updates, etc)
86 extern Monitor* MethodCompileQueue_lock; // a lock held when method compilations are enqueued, dequeued
87 #ifdef TIERED
88 extern Monitor* C1_lock; // a lock to ensure on single c1 compile is ever active
89 #endif // TIERED
90 extern Monitor* CompileThread_lock; // a lock held by compile threads during compilation system initialization
91 extern Mutex* CompileTaskAlloc_lock; // a lock held when CompileTasks are allocated
92 extern Mutex* CompileStatistics_lock; // a lock held when updating compilation statistics
93 extern Mutex* MultiArray_lock; // a lock used to guard allocation of multi-dim arrays
94 extern Monitor* Terminator_lock; // a lock used to guard termination of the vm
95 extern Monitor* BeforeExit_lock; // a lock used to guard cleanups and shutdown hooks
96 extern Monitor* Notify_lock; // a lock used to synchronize the start-up of the vm
97 extern Monitor* Interrupt_lock; // a lock used for condition variable mediated interrupt processing
98 extern Monitor* ProfileVM_lock; // a lock used for profiling the VMThread
99 extern Mutex* ProfilePrint_lock; // a lock used to serialize the printing of profiles
100 extern Mutex* ExceptionCache_lock; // a lock used to synchronize exception cache updates
101 extern Mutex* OsrList_lock; // a lock used to serialize access to OSR queues
103 #ifndef PRODUCT
104 extern Mutex* FullGCALot_lock; // a lock to make FullGCALot MT safe
105 #endif
106 extern Mutex* Debug1_lock; // A bunch of pre-allocated locks that can be used for tracing
107 extern Mutex* Debug2_lock; // down synchronization related bugs!
108 extern Mutex* Debug3_lock;
110 extern Mutex* RawMonitor_lock;
111 extern Mutex* PerfDataMemAlloc_lock; // a lock on the allocator for PerfData memory for performance data
112 extern Mutex* PerfDataManager_lock; // a long on access to PerfDataManager resources
113 extern Mutex* ParkerFreeList_lock;
114 extern Mutex* OopMapCacheAlloc_lock; // protects allocation of oop_map caches
116 extern Mutex* MMUTracker_lock; // protects the MMU
117 // tracker data structures
118 extern Mutex* HotCardCache_lock; // protects the hot card cache
120 extern Mutex* Management_lock; // a lock used to serialize JVM management
121 extern Monitor* LowMemory_lock; // a lock used for low memory detection
123 // A MutexLocker provides mutual exclusion with respect to a given mutex
124 // for the scope which contains the locker. The lock is an OS lock, not
125 // an object lock, and the two do not interoperate. Do not use Mutex-based
126 // locks to lock on Java objects, because they will not be respected if a
127 // that object is locked using the Java locking mechanism.
128 //
129 // NOTE WELL!!
130 //
131 // See orderAccess.hpp. We assume throughout the VM that MutexLocker's
132 // and friends constructors do a fence, a lock and an acquire *in that
133 // order*. And that their destructors do a release and unlock, in *that*
134 // order. If their implementations change such that these assumptions
135 // are violated, a whole lot of code will break.
137 // Print all mutexes/monitors that are currently owned by a thread; called
138 // by fatal error handler.
139 void print_owned_locks_on_error(outputStream* st);
141 char *lock_name(Mutex *mutex);
143 class MutexLocker: StackObj {
144 private:
145 Monitor * _mutex;
146 public:
147 MutexLocker(Monitor * mutex) {
148 assert(mutex->rank() != Mutex::special,
149 "Special ranked mutex should only use MutexLockerEx");
150 _mutex = mutex;
151 _mutex->lock();
152 }
154 // Overloaded constructor passing current thread
155 MutexLocker(Monitor * mutex, Thread *thread) {
156 assert(mutex->rank() != Mutex::special,
157 "Special ranked mutex should only use MutexLockerEx");
158 _mutex = mutex;
159 _mutex->lock(thread);
160 }
162 ~MutexLocker() {
163 _mutex->unlock();
164 }
166 };
168 // for debugging: check that we're already owning this lock (or are at a safepoint)
169 #ifdef ASSERT
170 void assert_locked_or_safepoint(const Monitor * lock);
171 void assert_lock_strong(const Monitor * lock);
172 #else
173 #define assert_locked_or_safepoint(lock)
174 #define assert_lock_strong(lock)
175 #endif
177 // A MutexLockerEx behaves like a MutexLocker when its constructor is
178 // called with a Mutex. Unlike a MutexLocker, its constructor can also be
179 // called with NULL, in which case the MutexLockerEx is a no-op. There
180 // is also a corresponding MutexUnlockerEx. We want to keep the
181 // basic MutexLocker as fast as possible. MutexLockerEx can also lock
182 // without safepoint check.
184 class MutexLockerEx: public StackObj {
185 private:
186 Monitor * _mutex;
187 public:
188 MutexLockerEx(Monitor * mutex, bool no_safepoint_check = !Mutex::_no_safepoint_check_flag) {
189 _mutex = mutex;
190 if (_mutex != NULL) {
191 assert(mutex->rank() > Mutex::special || no_safepoint_check,
192 "Mutexes with rank special or lower should not do safepoint checks");
193 if (no_safepoint_check)
194 _mutex->lock_without_safepoint_check();
195 else
196 _mutex->lock();
197 }
198 }
200 ~MutexLockerEx() {
201 if (_mutex != NULL) {
202 _mutex->unlock();
203 }
204 }
205 };
207 // A MonitorLockerEx is like a MutexLockerEx above, except it takes
208 // a possibly null Monitor, and allows wait/notify as well which are
209 // delegated to the underlying Monitor.
211 class MonitorLockerEx: public MutexLockerEx {
212 private:
213 Monitor * _monitor;
214 public:
215 MonitorLockerEx(Monitor* monitor,
216 bool no_safepoint_check = !Mutex::_no_safepoint_check_flag):
217 MutexLockerEx(monitor, no_safepoint_check),
218 _monitor(monitor) {
219 // Superclass constructor did locking
220 }
222 ~MonitorLockerEx() {
223 #ifdef ASSERT
224 if (_monitor != NULL) {
225 assert_lock_strong(_monitor);
226 }
227 #endif // ASSERT
228 // Superclass destructor will do unlocking
229 }
231 bool wait(bool no_safepoint_check = !Mutex::_no_safepoint_check_flag,
232 long timeout = 0,
233 bool as_suspend_equivalent = !Mutex::_as_suspend_equivalent_flag) {
234 if (_monitor != NULL) {
235 return _monitor->wait(no_safepoint_check, timeout, as_suspend_equivalent);
236 }
237 return false;
238 }
240 bool notify_all() {
241 if (_monitor != NULL) {
242 return _monitor->notify_all();
243 }
244 return true;
245 }
247 bool notify() {
248 if (_monitor != NULL) {
249 return _monitor->notify();
250 }
251 return true;
252 }
253 };
257 // A GCMutexLocker is usually initialized with a mutex that is
258 // automatically acquired in order to do GC. The function that
259 // synchronizes using a GCMutexLocker may be called both during and between
260 // GC's. Thus, it must acquire the mutex if GC is not in progress, but not
261 // if GC is in progress (since the mutex is already held on its behalf.)
263 class GCMutexLocker: public StackObj {
264 private:
265 Monitor * _mutex;
266 bool _locked;
267 public:
268 GCMutexLocker(Monitor * mutex);
269 ~GCMutexLocker() { if (_locked) _mutex->unlock(); }
270 };
274 // A MutexUnlocker temporarily exits a previously
275 // entered mutex for the scope which contains the unlocker.
277 class MutexUnlocker: StackObj {
278 private:
279 Monitor * _mutex;
281 public:
282 MutexUnlocker(Monitor * mutex) {
283 _mutex = mutex;
284 _mutex->unlock();
285 }
287 ~MutexUnlocker() {
288 _mutex->lock();
289 }
290 };
292 // A MutexUnlockerEx temporarily exits a previously
293 // entered mutex for the scope which contains the unlocker.
295 class MutexUnlockerEx: StackObj {
296 private:
297 Monitor * _mutex;
298 bool _no_safepoint_check;
300 public:
301 MutexUnlockerEx(Monitor * mutex, bool no_safepoint_check = !Mutex::_no_safepoint_check_flag) {
302 _mutex = mutex;
303 _no_safepoint_check = no_safepoint_check;
304 _mutex->unlock();
305 }
307 ~MutexUnlockerEx() {
308 if (_no_safepoint_check == Mutex::_no_safepoint_check_flag) {
309 _mutex->lock_without_safepoint_check();
310 } else {
311 _mutex->lock();
312 }
313 }
314 };
316 #ifndef PRODUCT
317 //
318 // A special MutexLocker that allows:
319 // - reentrant locking
320 // - locking out of order
321 //
322 // Only too be used for verify code, where we can relaxe out dead-lock
323 // dection code a bit (unsafe, but probably ok). This code is NEVER to
324 // be included in a product version.
325 //
326 class VerifyMutexLocker: StackObj {
327 private:
328 Monitor * _mutex;
329 bool _reentrant;
330 public:
331 VerifyMutexLocker(Monitor * mutex) {
332 _mutex = mutex;
333 _reentrant = mutex->owned_by_self();
334 if (!_reentrant) {
335 // We temp. diable strict safepoint checking, while we require the lock
336 FlagSetting fs(StrictSafepointChecks, false);
337 _mutex->lock();
338 }
339 }
341 ~VerifyMutexLocker() {
342 if (!_reentrant) {
343 _mutex->unlock();
344 }
345 }
346 };
348 #endif