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.
22 *
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 Mutex* Stacktrace_lock; // used to guard access to the stacktrace table
141
142 extern Monitor* JfrQuery_lock; // protects JFR use
143 extern Monitor* JfrMsg_lock; // protects JFR messaging
144 extern Mutex* JfrBuffer_lock; // protects JFR buffer operations
145 extern Mutex* JfrStream_lock; // protects JFR stream access
146 extern Monitor* PeriodicTask_lock; // protects the periodic task structure
147
148 // A MutexLocker provides mutual exclusion with respect to a given mutex
149 // for the scope which contains the locker. The lock is an OS lock, not
150 // an object lock, and the two do not interoperate. Do not use Mutex-based
151 // locks to lock on Java objects, because they will not be respected if a
152 // that object is locked using the Java locking mechanism.
153 //
154 // NOTE WELL!!
155 //
156 // See orderAccess.hpp. We assume throughout the VM that MutexLocker's
157 // and friends constructors do a fence, a lock and an acquire *in that
158 // order*. And that their destructors do a release and unlock, in *that*
159 // order. If their implementations change such that these assumptions
160 // are violated, a whole lot of code will break.
161
162 // Print all mutexes/monitors that are currently owned by a thread; called
163 // by fatal error handler.
164 void print_owned_locks_on_error(outputStream* st);
165
166 char *lock_name(Mutex *mutex);
167
168 class MutexLocker: StackObj {
169 private:
170 Monitor * _mutex;
171 public:
172 MutexLocker(Monitor * mutex) {
173 assert(mutex->rank() != Mutex::special,
174 "Special ranked mutex should only use MutexLockerEx");
175 _mutex = mutex;
176 _mutex->lock();
177 }
178
179 // Overloaded constructor passing current thread
180 MutexLocker(Monitor * mutex, Thread *thread) {
181 assert(mutex->rank() != Mutex::special,
182 "Special ranked mutex should only use MutexLockerEx");
183 _mutex = mutex;
184 _mutex->lock(thread);
185 }
186
187 ~MutexLocker() {
188 _mutex->unlock();
189 }
190
191 };
192
193 // for debugging: check that we're already owning this lock (or are at a safepoint)
194 #ifdef ASSERT
195 void assert_locked_or_safepoint(const Monitor * lock);
196 void assert_lock_strong(const Monitor * lock);
197 #else
198 #define assert_locked_or_safepoint(lock)
199 #define assert_lock_strong(lock)
200 #endif
201
202 // A MutexLockerEx behaves like a MutexLocker when its constructor is
203 // called with a Mutex. Unlike a MutexLocker, its constructor can also be
204 // called with NULL, in which case the MutexLockerEx is a no-op. There
205 // is also a corresponding MutexUnlockerEx. We want to keep the
206 // basic MutexLocker as fast as possible. MutexLockerEx can also lock
207 // without safepoint check.
208
209 class MutexLockerEx: public StackObj {
210 private:
211 Monitor * _mutex;
212 public:
213 MutexLockerEx(Monitor * mutex, bool no_safepoint_check = !Mutex::_no_safepoint_check_flag) {
214 _mutex = mutex;
215 if (_mutex != NULL) {
216 assert(mutex->rank() > Mutex::special || no_safepoint_check,
217 "Mutexes with rank special or lower should not do safepoint checks");
218 if (no_safepoint_check)
219 _mutex->lock_without_safepoint_check();
220 else
221 _mutex->lock();
222 }
223 }
224
225 ~MutexLockerEx() {
226 if (_mutex != NULL) {
227 _mutex->unlock();
228 }
229 }
230 };
231
232 // A MonitorLockerEx is like a MutexLockerEx above, except it takes
233 // a possibly null Monitor, and allows wait/notify as well which are
234 // delegated to the underlying Monitor.
235
236 class MonitorLockerEx: public MutexLockerEx {
237 private:
238 Monitor * _monitor;
239 public:
240 MonitorLockerEx(Monitor* monitor,
241 bool no_safepoint_check = !Mutex::_no_safepoint_check_flag):
242 MutexLockerEx(monitor, no_safepoint_check),
243 _monitor(monitor) {
244 // Superclass constructor did locking
245 }
246
247 ~MonitorLockerEx() {
248 #ifdef ASSERT
249 if (_monitor != NULL) {
250 assert_lock_strong(_monitor);
251 }
252 #endif // ASSERT
253 // Superclass destructor will do unlocking
254 }
255
256 bool wait(bool no_safepoint_check = !Mutex::_no_safepoint_check_flag,
257 long timeout = 0,
258 bool as_suspend_equivalent = !Mutex::_as_suspend_equivalent_flag) {
259 if (_monitor != NULL) {
260 return _monitor->wait(no_safepoint_check, timeout, as_suspend_equivalent);
261 }
262 return false;
263 }
264
265 bool notify_all() {
266 if (_monitor != NULL) {
267 return _monitor->notify_all();
268 }
269 return true;
270 }
271
272 bool notify() {
273 if (_monitor != NULL) {
274 return _monitor->notify();
275 }
276 return true;
277 }
278 };
279
280
281
282 // A GCMutexLocker is usually initialized with a mutex that is
283 // automatically acquired in order to do GC. The function that
284 // synchronizes using a GCMutexLocker may be called both during and between
285 // GC's. Thus, it must acquire the mutex if GC is not in progress, but not
286 // if GC is in progress (since the mutex is already held on its behalf.)
287
288 class GCMutexLocker: public StackObj {
289 private:
290 Monitor * _mutex;
291 bool _locked;
292 public:
293 GCMutexLocker(Monitor * mutex);
294 ~GCMutexLocker() { if (_locked) _mutex->unlock(); }
295 };
296
297
298
299 // A MutexUnlocker temporarily exits a previously
300 // entered mutex for the scope which contains the unlocker.
301
302 class MutexUnlocker: StackObj {
303 private:
304 Monitor * _mutex;
305
306 public:
307 MutexUnlocker(Monitor * mutex) {
308 _mutex = mutex;
309 _mutex->unlock();
310 }
311
312 ~MutexUnlocker() {
313 _mutex->lock();
314 }
315 };
316
317 // A MutexUnlockerEx temporarily exits a previously
318 // entered mutex for the scope which contains the unlocker.
319
320 class MutexUnlockerEx: StackObj {
321 private:
322 Monitor * _mutex;
323 bool _no_safepoint_check;
324
325 public:
326 MutexUnlockerEx(Monitor * mutex, bool no_safepoint_check = !Mutex::_no_safepoint_check_flag) {
327 _mutex = mutex;
328 _no_safepoint_check = no_safepoint_check;
329 _mutex->unlock();
330 }
331
332 ~MutexUnlockerEx() {
333 if (_no_safepoint_check == Mutex::_no_safepoint_check_flag) {
334 _mutex->lock_without_safepoint_check();
335 } else {
336 _mutex->lock();
337 }
338 }
339 };
340
341 #ifndef PRODUCT
342 //
343 // A special MutexLocker that allows:
344 // - reentrant locking
345 // - locking out of order
346 //
347 // Only too be used for verify code, where we can relaxe out dead-lock
348 // dection code a bit (unsafe, but probably ok). This code is NEVER to
349 // be included in a product version.
350 //
351 class VerifyMutexLocker: StackObj {
352 private:
353 Monitor * _mutex;
354 bool _reentrant;
355 public:
356 VerifyMutexLocker(Monitor * mutex) {
357 _mutex = mutex;
358 _reentrant = mutex->owned_by_self();
359 if (!_reentrant) {
360 // We temp. diable strict safepoint checking, while we require the lock
361 FlagSetting fs(StrictSafepointChecks, false);
362 _mutex->lock();
363 }
364 }
365
366 ~VerifyMutexLocker() {
367 if (!_reentrant) {
368 _mutex->unlock();
369 }
370 }
371 };
372
373 #endif
374
375 #endif // SHARE_VM_RUNTIME_MUTEXLOCKER_HPP