1 /*
2 * Copyright (c) 1997, 2013, 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_aix
40 # include "os_aix.inline.hpp"
41 #endif
42 #ifdef TARGET_OS_FAMILY_bsd
43 # include "os_bsd.inline.hpp"
44 #endif
45
46 // Mutexes used in the VM.
47
48 extern Mutex* Patching_lock; // a lock used to guard code patching of compiled code
49 extern Monitor* SystemDictionary_lock; // a lock on the system dictionary
50 extern Mutex* PackageTable_lock; // a lock on the class loader package table
51 extern Mutex* CompiledIC_lock; // a lock used to guard compiled IC patching and access
52 extern Mutex* InlineCacheBuffer_lock; // a lock used to guard the InlineCacheBuffer
53 extern Mutex* VMStatistic_lock; // a lock used to guard statistics count increment
54 extern Mutex* JNIGlobalHandle_lock; // a lock on creating JNI global handles
55 extern Mutex* JNIHandleBlockFreeList_lock; // a lock on the JNI handle block free list
56 extern Mutex* MemberNameTable_lock; // a lock on the MemberNameTable updates
57 extern Mutex* JmethodIdCreation_lock; // a lock on creating JNI method identifiers
58 extern Mutex* JfieldIdCreation_lock; // a lock on creating JNI static field identifiers
59 extern Monitor* JNICritical_lock; // a lock used while entering and exiting JNI critical regions, allows GC to sometimes get in
60 extern Mutex* JvmtiThreadState_lock; // a lock on modification of JVMTI thread data
61 extern Monitor* JvmtiPendingEvent_lock; // a lock on the JVMTI pending events list
62 extern Monitor* Heap_lock; // a lock on the heap
63 extern Mutex* ExpandHeap_lock; // a lock on expanding the heap
64 extern Mutex* AdapterHandlerLibrary_lock; // a lock on the AdapterHandlerLibrary
65 extern Mutex* SignatureHandlerLibrary_lock; // a lock on the SignatureHandlerLibrary
66 extern Mutex* VtableStubs_lock; // a lock on the VtableStubs
67 extern Mutex* SymbolTable_lock; // a lock on the symbol table
68 extern Mutex* StringTable_lock; // a lock on the interned string table
69 extern Mutex* CodeCache_lock; // a lock on the CodeCache, rank is special, use MutexLockerEx
70 extern Mutex* MethodData_lock; // a lock on installation of method data
71 extern Mutex* RetData_lock; // a lock on installation of RetData inside method data
72 extern Mutex* DerivedPointerTableGC_lock; // a lock to protect the derived pointer table
73 extern Monitor* VMOperationQueue_lock; // a lock on queue of vm_operations waiting to execute
74 extern Monitor* VMOperationRequest_lock; // a lock on Threads waiting for a vm_operation to terminate
75 extern Monitor* Safepoint_lock; // a lock used by the safepoint abstraction
76 extern Monitor* Threads_lock; // a lock on the Threads table of active Java threads
77 // (also used by Safepoints too to block threads creation/destruction)
78 extern Monitor* CGC_lock; // used for coordination between
79 // fore- & background GC threads.
80 extern Mutex* STS_init_lock; // coordinate initialization of SuspendibleThreadSets.
81 extern Monitor* SLT_lock; // used in CMS GC for acquiring PLL
82 extern Monitor* iCMS_lock; // CMS incremental mode start/stop notification
83 extern Monitor* FullGCCount_lock; // in support of "concurrent" full gc
84 extern Monitor* CMark_lock; // used for concurrent mark thread coordination
85 extern Mutex* CMRegionStack_lock; // used for protecting accesses to the CM region stack
86 extern Mutex* SATB_Q_FL_lock; // Protects SATB Q
87 // buffer free list.
88 extern Monitor* SATB_Q_CBL_mon; // Protects SATB Q
89 // completed buffer queue.
90 extern Mutex* Shared_SATB_Q_lock; // Lock protecting SATB
91 // queue shared by
92 // non-Java threads.
93
94 extern Mutex* DirtyCardQ_FL_lock; // Protects dirty card Q
95 // buffer free list.
96 extern Monitor* DirtyCardQ_CBL_mon; // Protects dirty card Q
97 // completed buffer queue.
98 extern Mutex* Shared_DirtyCardQ_lock; // Lock protecting dirty card
99 // queue shared by
100 // non-Java threads.
101 // (see option ExplicitGCInvokesConcurrent)
102 extern Mutex* ParGCRareEvent_lock; // Synchronizes various (rare) parallel GC ops.
103 extern Mutex* EvacFailureStack_lock; // guards the evac failure scan stack
104 extern Mutex* Compile_lock; // a lock held when Compilation is updating code (used to block CodeCache traversal, CHA updates, etc)
105 extern Monitor* MethodCompileQueue_lock; // a lock held when method compilations are enqueued, dequeued
106 extern Monitor* CompileThread_lock; // a lock held by compile threads during compilation system initialization
107 extern Mutex* CompileTaskAlloc_lock; // a lock held when CompileTasks are allocated
108 extern Mutex* CompileStatistics_lock; // a lock held when updating compilation statistics
109 extern Mutex* MultiArray_lock; // a lock used to guard allocation of multi-dim arrays
110 extern Monitor* Terminator_lock; // a lock used to guard termination of the vm
111 extern Monitor* BeforeExit_lock; // a lock used to guard cleanups and shutdown hooks
112 extern Monitor* Notify_lock; // a lock used to synchronize the start-up of the vm
113 extern Monitor* Interrupt_lock; // a lock used for condition variable mediated interrupt processing
114 extern Monitor* ProfileVM_lock; // a lock used for profiling the VMThread
115 extern Mutex* ProfilePrint_lock; // a lock used to serialize the printing of profiles
116 extern Mutex* ExceptionCache_lock; // a lock used to synchronize exception cache updates
117 extern Mutex* OsrList_lock; // a lock used to serialize access to OSR queues
118
119 #ifndef PRODUCT
120 extern Mutex* FullGCALot_lock; // a lock to make FullGCALot MT safe
121 #endif // PRODUCT
122 extern Mutex* Debug1_lock; // A bunch of pre-allocated locks that can be used for tracing
123 extern Mutex* Debug2_lock; // down synchronization related bugs!
124 extern Mutex* Debug3_lock;
125
126 extern Mutex* RawMonitor_lock;
127 extern Mutex* PerfDataMemAlloc_lock; // a lock on the allocator for PerfData memory for performance data
128 extern Mutex* PerfDataManager_lock; // a long on access to PerfDataManager resources
129 extern Mutex* ParkerFreeList_lock;
130 extern Mutex* OopMapCacheAlloc_lock; // protects allocation of oop_map caches
131
132 extern Mutex* FreeList_lock; // protects the free region list during safepoints
133 extern Monitor* SecondaryFreeList_lock; // protects the secondary free region list
134 extern Mutex* OldSets_lock; // protects the old region sets
135 extern Monitor* RootRegionScan_lock; // used to notify that the CM threads have finished scanning the IM snapshot regions
136 extern Mutex* MMUTracker_lock; // protects the MMU
137 // tracker data structures
138 extern Mutex* HotCardCache_lock; // protects the hot card cache
139
140 extern Mutex* Management_lock; // a lock used to serialize JVM management
141 extern Monitor* Service_lock; // a lock used for service thread operation
142 extern Monitor* PeriodicTask_lock; // protects the periodic task structure
143
144 #ifdef INCLUDE_TRACE
145 extern Mutex* JfrStacktrace_lock; // used to guard access to the JFR stacktrace table
146 extern Monitor* JfrMsg_lock; // protects JFR messaging
147 extern Mutex* JfrBuffer_lock; // protects JFR buffer operations
148 extern Mutex* JfrStream_lock; // protects JFR stream access
149 extern Mutex* JfrThreadGroups_lock; // protects JFR access to Thread Groups
150 #endif
151
152 // A MutexLocker provides mutual exclusion with respect to a given mutex
153 // for the scope which contains the locker. The lock is an OS lock, not
154 // an object lock, and the two do not interoperate. Do not use Mutex-based
155 // locks to lock on Java objects, because they will not be respected if a
156 // that object is locked using the Java locking mechanism.
157 //
158 // NOTE WELL!!
159 //
160 // See orderAccess.hpp. We assume throughout the VM that MutexLocker's
161 // and friends constructors do a fence, a lock and an acquire *in that
162 // order*. And that their destructors do a release and unlock, in *that*
163 // order. If their implementations change such that these assumptions
164 // are violated, a whole lot of code will break.
165
166 // Print all mutexes/monitors that are currently owned by a thread; called
167 // by fatal error handler.
168 void print_owned_locks_on_error(outputStream* st);
169
170 char *lock_name(Mutex *mutex);
171
172 class MutexLocker: StackObj {
173 private:
174 Monitor * _mutex;
175 public:
176 MutexLocker(Monitor * mutex) {
177 assert(mutex->rank() != Mutex::special,
178 "Special ranked mutex should only use MutexLockerEx");
179 _mutex = mutex;
180 _mutex->lock();
181 }
182
183 // Overloaded constructor passing current thread
184 MutexLocker(Monitor * mutex, Thread *thread) {
185 assert(mutex->rank() != Mutex::special,
186 "Special ranked mutex should only use MutexLockerEx");
187 _mutex = mutex;
188 _mutex->lock(thread);
189 }
190
191 ~MutexLocker() {
192 _mutex->unlock();
193 }
194
195 };
196
197 // for debugging: check that we're already owning this lock (or are at a safepoint)
198 #ifdef ASSERT
199 void assert_locked_or_safepoint(const Monitor * lock);
200 void assert_lock_strong(const Monitor * lock);
201 #else
202 #define assert_locked_or_safepoint(lock)
203 #define assert_lock_strong(lock)
204 #endif
205
206 // A MutexLockerEx behaves like a MutexLocker when its constructor is
207 // called with a Mutex. Unlike a MutexLocker, its constructor can also be
208 // called with NULL, in which case the MutexLockerEx is a no-op. There
209 // is also a corresponding MutexUnlockerEx. We want to keep the
210 // basic MutexLocker as fast as possible. MutexLockerEx can also lock
211 // without safepoint check.
212
213 class MutexLockerEx: public StackObj {
214 private:
215 Monitor * _mutex;
216 public:
217 MutexLockerEx(Monitor * mutex, bool no_safepoint_check = !Mutex::_no_safepoint_check_flag) {
218 _mutex = mutex;
219 if (_mutex != NULL) {
220 assert(mutex->rank() > Mutex::special || no_safepoint_check,
221 "Mutexes with rank special or lower should not do safepoint checks");
222 if (no_safepoint_check)
223 _mutex->lock_without_safepoint_check();
224 else
225 _mutex->lock();
226 }
227 }
228
229 ~MutexLockerEx() {
230 if (_mutex != NULL) {
231 _mutex->unlock();
232 }
233 }
234 };
235
236 // A MonitorLockerEx is like a MutexLockerEx above, except it takes
237 // a possibly null Monitor, and allows wait/notify as well which are
238 // delegated to the underlying Monitor.
239
240 class MonitorLockerEx: public MutexLockerEx {
241 private:
242 Monitor * _monitor;
243 public:
244 MonitorLockerEx(Monitor* monitor,
245 bool no_safepoint_check = !Mutex::_no_safepoint_check_flag):
246 MutexLockerEx(monitor, no_safepoint_check),
247 _monitor(monitor) {
248 // Superclass constructor did locking
249 }
250
251 ~MonitorLockerEx() {
252 #ifdef ASSERT
253 if (_monitor != NULL) {
254 assert_lock_strong(_monitor);
255 }
256 #endif // ASSERT
257 // Superclass destructor will do unlocking
258 }
259
260 bool wait(bool no_safepoint_check = !Mutex::_no_safepoint_check_flag,
261 long timeout = 0,
262 bool as_suspend_equivalent = !Mutex::_as_suspend_equivalent_flag) {
263 if (_monitor != NULL) {
264 return _monitor->wait(no_safepoint_check, timeout, as_suspend_equivalent);
265 }
266 return false;
267 }
268
269 bool notify_all() {
270 if (_monitor != NULL) {
271 return _monitor->notify_all();
272 }
273 return true;
274 }
275
276 bool notify() {
277 if (_monitor != NULL) {
278 return _monitor->notify();
279 }
280 return true;
281 }
282 };
283
284
285
286 // A GCMutexLocker is usually initialized with a mutex that is
287 // automatically acquired in order to do GC. The function that
288 // synchronizes using a GCMutexLocker may be called both during and between
289 // GC's. Thus, it must acquire the mutex if GC is not in progress, but not
290 // if GC is in progress (since the mutex is already held on its behalf.)
291
292 class GCMutexLocker: public StackObj {
293 private:
294 Monitor * _mutex;
295 bool _locked;
296 public:
297 GCMutexLocker(Monitor * mutex);
298 ~GCMutexLocker() { if (_locked) _mutex->unlock(); }
299 };
300
301
302
303 // A MutexUnlocker temporarily exits a previously
304 // entered mutex for the scope which contains the unlocker.
305
306 class MutexUnlocker: StackObj {
307 private:
308 Monitor * _mutex;
309
310 public:
311 MutexUnlocker(Monitor * mutex) {
312 _mutex = mutex;
313 _mutex->unlock();
314 }
315
316 ~MutexUnlocker() {
317 _mutex->lock();
318 }
319 };
320
321 // A MutexUnlockerEx temporarily exits a previously
322 // entered mutex for the scope which contains the unlocker.
323
324 class MutexUnlockerEx: StackObj {
325 private:
326 Monitor * _mutex;
327 bool _no_safepoint_check;
328
329 public:
330 MutexUnlockerEx(Monitor * mutex, bool no_safepoint_check = !Mutex::_no_safepoint_check_flag) {
331 _mutex = mutex;
332 _no_safepoint_check = no_safepoint_check;
333 _mutex->unlock();
334 }
335
336 ~MutexUnlockerEx() {
337 if (_no_safepoint_check == Mutex::_no_safepoint_check_flag) {
338 _mutex->lock_without_safepoint_check();
339 } else {
340 _mutex->lock();
341 }
342 }
343 };
344
345 #ifndef PRODUCT
346 //
347 // A special MutexLocker that allows:
348 // - reentrant locking
349 // - locking out of order
350 //
351 // Only to be used for verify code, where we can relax out dead-lock
352 // detection code a bit (unsafe, but probably ok). This code is NEVER to
353 // be included in a product version.
354 //
355 class VerifyMutexLocker: StackObj {
356 private:
357 Monitor * _mutex;
358 bool _reentrant;
359 public:
360 VerifyMutexLocker(Monitor * mutex) {
361 _mutex = mutex;
362 _reentrant = mutex->owned_by_self();
363 if (!_reentrant) {
364 // We temp. disable strict safepoint checking, while we require the lock
365 FlagSetting fs(StrictSafepointChecks, false);
366 _mutex->lock();
367 }
368 }
369
370 ~VerifyMutexLocker() {
371 if (!_reentrant) {
372 _mutex->unlock();
373 }
374 }
375 };
376
377 #endif
378
379 #endif // SHARE_VM_RUNTIME_MUTEXLOCKER_HPP