Tue, 23 Nov 2010 13:22:55 -0800
6989984: Use standard include model for Hospot
Summary: Replaced MakeDeps and the includeDB files with more standardized solutions.
Reviewed-by: coleenp, kvn, kamg
1 /*
2 * Copyright (c) 1998, 2010, 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 #ifndef SHARE_VM_RUNTIME_OBJECTMONITOR_HPP
26 #define SHARE_VM_RUNTIME_OBJECTMONITOR_HPP
28 #include "runtime/os.hpp"
29 #include "runtime/perfData.hpp"
32 // ObjectWaiter serves as a "proxy" or surrogate thread.
33 // TODO-FIXME: Eliminate ObjectWaiter and use the thread-specific
34 // ParkEvent instead. Beware, however, that the JVMTI code
35 // knows about ObjectWaiters, so we'll have to reconcile that code.
36 // See next_waiter(), first_waiter(), etc.
38 class ObjectWaiter : public StackObj {
39 public:
40 enum TStates { TS_UNDEF, TS_READY, TS_RUN, TS_WAIT, TS_ENTER, TS_CXQ } ;
41 enum Sorted { PREPEND, APPEND, SORTED } ;
42 ObjectWaiter * volatile _next;
43 ObjectWaiter * volatile _prev;
44 Thread* _thread;
45 ParkEvent * _event;
46 volatile int _notified ;
47 volatile TStates TState ;
48 Sorted _Sorted ; // List placement disposition
49 bool _active ; // Contention monitoring is enabled
50 public:
51 ObjectWaiter(Thread* thread);
53 void wait_reenter_begin(ObjectMonitor *mon);
54 void wait_reenter_end(ObjectMonitor *mon);
55 };
57 // WARNING:
58 // This is a very sensitive and fragile class. DO NOT make any
59 // change unless you are fully aware of the underlying semantics.
61 // This class can not inherit from any other class, because I have
62 // to let the displaced header be the very first word. Otherwise I
63 // have to let markOop include this file, which would export the
64 // monitor data structure to everywhere.
65 //
66 // The ObjectMonitor class is used to implement JavaMonitors which have
67 // transformed from the lightweight structure of the thread stack to a
68 // heavy weight lock due to contention
70 // It is also used as RawMonitor by the JVMTI
73 class ObjectMonitor {
74 public:
75 enum {
76 OM_OK, // no error
77 OM_SYSTEM_ERROR, // operating system error
78 OM_ILLEGAL_MONITOR_STATE, // IllegalMonitorStateException
79 OM_INTERRUPTED, // Thread.interrupt()
80 OM_TIMED_OUT // Object.wait() timed out
81 };
83 public:
84 // TODO-FIXME: the "offset" routines should return a type of off_t instead of int ...
85 // ByteSize would also be an appropriate type.
86 static int header_offset_in_bytes() { return offset_of(ObjectMonitor, _header); }
87 static int object_offset_in_bytes() { return offset_of(ObjectMonitor, _object); }
88 static int owner_offset_in_bytes() { return offset_of(ObjectMonitor, _owner); }
89 static int count_offset_in_bytes() { return offset_of(ObjectMonitor, _count); }
90 static int recursions_offset_in_bytes() { return offset_of(ObjectMonitor, _recursions); }
91 static int cxq_offset_in_bytes() { return offset_of(ObjectMonitor, _cxq) ; }
92 static int succ_offset_in_bytes() { return offset_of(ObjectMonitor, _succ) ; }
93 static int EntryList_offset_in_bytes() { return offset_of(ObjectMonitor, _EntryList); }
94 static int FreeNext_offset_in_bytes() { return offset_of(ObjectMonitor, FreeNext); }
95 static int WaitSet_offset_in_bytes() { return offset_of(ObjectMonitor, _WaitSet) ; }
96 static int Responsible_offset_in_bytes() { return offset_of(ObjectMonitor, _Responsible);}
97 static int Spinner_offset_in_bytes() { return offset_of(ObjectMonitor, _Spinner); }
99 public:
100 // Eventaully we'll make provisions for multiple callbacks, but
101 // now one will suffice.
102 static int (*SpinCallbackFunction)(intptr_t, int) ;
103 static intptr_t SpinCallbackArgument ;
106 public:
107 markOop header() const;
108 void set_header(markOop hdr);
110 intptr_t is_busy() const {
111 // TODO-FIXME: merge _count and _waiters.
112 // TODO-FIXME: assert _owner == null implies _recursions = 0
113 // TODO-FIXME: assert _WaitSet != null implies _count > 0
114 return _count|_waiters|intptr_t(_owner)|intptr_t(_cxq)|intptr_t(_EntryList ) ;
115 }
117 intptr_t is_entered(Thread* current) const;
119 void* owner() const;
120 void set_owner(void* owner);
122 intptr_t waiters() const;
124 intptr_t count() const;
125 void set_count(intptr_t count);
126 intptr_t contentions() const ;
127 intptr_t recursions() const { return _recursions; }
129 // JVM/DI GetMonitorInfo() needs this
130 ObjectWaiter* first_waiter() { return _WaitSet; }
131 ObjectWaiter* next_waiter(ObjectWaiter* o) { return o->_next; }
132 Thread* thread_of_waiter(ObjectWaiter* o) { return o->_thread; }
134 // initialize the monitor, exception the semaphore, all other fields
135 // are simple integers or pointers
136 ObjectMonitor() {
137 _header = NULL;
138 _count = 0;
139 _waiters = 0,
140 _recursions = 0;
141 _object = NULL;
142 _owner = NULL;
143 _WaitSet = NULL;
144 _WaitSetLock = 0 ;
145 _Responsible = NULL ;
146 _succ = NULL ;
147 _cxq = NULL ;
148 FreeNext = NULL ;
149 _EntryList = NULL ;
150 _SpinFreq = 0 ;
151 _SpinClock = 0 ;
152 OwnerIsThread = 0 ;
153 }
155 ~ObjectMonitor() {
156 // TODO: Add asserts ...
157 // _cxq == 0 _succ == NULL _owner == NULL _waiters == 0
158 // _count == 0 _EntryList == NULL etc
159 }
161 private:
162 void Recycle () {
163 // TODO: add stronger asserts ...
164 // _cxq == 0 _succ == NULL _owner == NULL _waiters == 0
165 // _count == 0 EntryList == NULL
166 // _recursions == 0 _WaitSet == NULL
167 // TODO: assert (is_busy()|_recursions) == 0
168 _succ = NULL ;
169 _EntryList = NULL ;
170 _cxq = NULL ;
171 _WaitSet = NULL ;
172 _recursions = 0 ;
173 _SpinFreq = 0 ;
174 _SpinClock = 0 ;
175 OwnerIsThread = 0 ;
176 }
178 public:
180 void* object() const;
181 void* object_addr();
182 void set_object(void* obj);
184 bool check(TRAPS); // true if the thread owns the monitor.
185 void check_slow(TRAPS);
186 void clear();
187 #ifndef PRODUCT
188 void verify();
189 void print();
190 #endif
192 bool try_enter (TRAPS) ;
193 void enter(TRAPS);
194 void exit(TRAPS);
195 void wait(jlong millis, bool interruptable, TRAPS);
196 void notify(TRAPS);
197 void notifyAll(TRAPS);
199 // Use the following at your own risk
200 intptr_t complete_exit(TRAPS);
201 void reenter(intptr_t recursions, TRAPS);
203 private:
204 void AddWaiter (ObjectWaiter * waiter) ;
205 static void DeferredInitialize();
207 ObjectWaiter * DequeueWaiter () ;
208 void DequeueSpecificWaiter (ObjectWaiter * waiter) ;
209 void EnterI (TRAPS) ;
210 void ReenterI (Thread * Self, ObjectWaiter * SelfNode) ;
211 void UnlinkAfterAcquire (Thread * Self, ObjectWaiter * SelfNode) ;
212 int TryLock (Thread * Self) ;
213 int NotRunnable (Thread * Self, Thread * Owner) ;
214 int TrySpin_Fixed (Thread * Self) ;
215 int TrySpin_VaryFrequency (Thread * Self) ;
216 int TrySpin_VaryDuration (Thread * Self) ;
217 void ctAsserts () ;
218 void ExitEpilog (Thread * Self, ObjectWaiter * Wakee) ;
219 bool ExitSuspendEquivalent (JavaThread * Self) ;
221 private:
222 friend class ObjectSynchronizer;
223 friend class ObjectWaiter;
224 friend class VMStructs;
226 // WARNING: this must be the very first word of ObjectMonitor
227 // This means this class can't use any virtual member functions.
228 // TODO-FIXME: assert that offsetof(_header) is 0 or get rid of the
229 // implicit 0 offset in emitted code.
231 volatile markOop _header; // displaced object header word - mark
232 void* volatile _object; // backward object pointer - strong root
234 double SharingPad [1] ; // temp to reduce false sharing
236 // All the following fields must be machine word aligned
237 // The VM assumes write ordering wrt these fields, which can be
238 // read from other threads.
240 protected: // protected for jvmtiRawMonitor
241 void * volatile _owner; // pointer to owning thread OR BasicLock
242 volatile intptr_t _recursions; // recursion count, 0 for first entry
243 private:
244 int OwnerIsThread ; // _owner is (Thread *) vs SP/BasicLock
245 ObjectWaiter * volatile _cxq ; // LL of recently-arrived threads blocked on entry.
246 // The list is actually composed of WaitNodes, acting
247 // as proxies for Threads.
248 protected:
249 ObjectWaiter * volatile _EntryList ; // Threads blocked on entry or reentry.
250 private:
251 Thread * volatile _succ ; // Heir presumptive thread - used for futile wakeup throttling
252 Thread * volatile _Responsible ;
253 int _PromptDrain ; // rqst to drain cxq into EntryList ASAP
255 volatile int _Spinner ; // for exit->spinner handoff optimization
256 volatile int _SpinFreq ; // Spin 1-out-of-N attempts: success rate
257 volatile int _SpinClock ;
258 volatile int _SpinDuration ;
259 volatile intptr_t _SpinState ; // MCS/CLH list of spinners
261 // TODO-FIXME: _count, _waiters and _recursions should be of
262 // type int, or int32_t but not intptr_t. There's no reason
263 // to use 64-bit fields for these variables on a 64-bit JVM.
265 volatile intptr_t _count; // reference count to prevent reclaimation/deflation
266 // at stop-the-world time. See deflate_idle_monitors().
267 // _count is approximately |_WaitSet| + |_EntryList|
268 protected:
269 volatile intptr_t _waiters; // number of waiting threads
270 private:
271 protected:
272 ObjectWaiter * volatile _WaitSet; // LL of threads wait()ing on the monitor
273 private:
274 volatile int _WaitSetLock; // protects Wait Queue - simple spinlock
276 public:
277 int _QMix ; // Mixed prepend queue discipline
278 ObjectMonitor * FreeNext ; // Free list linkage
279 intptr_t StatA, StatsB ;
281 public:
282 static void Initialize () ;
283 static PerfCounter * _sync_ContendedLockAttempts ;
284 static PerfCounter * _sync_FutileWakeups ;
285 static PerfCounter * _sync_Parks ;
286 static PerfCounter * _sync_EmptyNotifications ;
287 static PerfCounter * _sync_Notifications ;
288 static PerfCounter * _sync_SlowEnter ;
289 static PerfCounter * _sync_SlowExit ;
290 static PerfCounter * _sync_SlowNotify ;
291 static PerfCounter * _sync_SlowNotifyAll ;
292 static PerfCounter * _sync_FailedSpins ;
293 static PerfCounter * _sync_SuccessfulSpins ;
294 static PerfCounter * _sync_PrivateA ;
295 static PerfCounter * _sync_PrivateB ;
296 static PerfCounter * _sync_MonInCirculation ;
297 static PerfCounter * _sync_MonScavenged ;
298 static PerfCounter * _sync_Inflations ;
299 static PerfCounter * _sync_Deflations ;
300 static PerfLongVariable * _sync_MonExtant ;
302 public:
303 static int Knob_Verbose;
304 static int Knob_SpinLimit;
305 };
307 #undef TEVENT
308 #define TEVENT(nom) {if (SyncVerbose) FEVENT(nom); }
310 #define FEVENT(nom) { static volatile int ctr = 0 ; int v = ++ctr ; if ((v & (v-1)) == 0) { ::printf (#nom " : %d \n", v); ::fflush(stdout); }}
312 #undef TEVENT
313 #define TEVENT(nom) {;}
316 #endif // SHARE_VM_RUNTIME_OBJECTMONITOR_HPP