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