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) 2003, 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_CLASSFILE_PLACEHOLDERS_HPP
26 #define SHARE_VM_CLASSFILE_PLACEHOLDERS_HPP
28 #include "utilities/hashtable.hpp"
30 class PlaceholderEntry;
32 // Placeholder objects. These represent classes currently
33 // being loaded, as well as arrays of primitives.
34 //
36 class PlaceholderTable : public TwoOopHashtable {
37 friend class VMStructs;
39 public:
40 PlaceholderTable(int table_size);
42 PlaceholderEntry* new_entry(int hash, symbolOop name, oop loader, bool havesupername, symbolOop supername);
44 PlaceholderEntry* bucket(int i) {
45 return (PlaceholderEntry*)Hashtable::bucket(i);
46 }
48 PlaceholderEntry** bucket_addr(int i) {
49 return (PlaceholderEntry**)Hashtable::bucket_addr(i);
50 }
52 void add_entry(int index, PlaceholderEntry* new_entry) {
53 Hashtable::add_entry(index, (HashtableEntry*)new_entry);
54 }
56 void add_entry(int index, unsigned int hash, symbolHandle name,
57 Handle loader, bool havesupername, symbolHandle supername);
59 // This returns a symbolOop to match type for SystemDictionary
60 symbolOop find_entry(int index, unsigned int hash,
61 symbolHandle name, Handle loader);
63 PlaceholderEntry* get_entry(int index, unsigned int hash,
64 symbolHandle name, Handle loader);
66 // caller to create a placeholder entry must enumerate an action
67 // caller claims ownership of that action
68 // For parallel classloading:
69 // multiple LOAD_INSTANCE threads can proceed in parallel
70 // multiple LOAD_SUPER threads can proceed in parallel
71 // LOAD_SUPER needed to check for class circularity
72 // DEFINE_CLASS: ultimately define class must be single threaded
73 // on a class/classloader basis
74 // so the head of that queue owns the token
75 // and the rest of the threads return the result the first thread gets
76 enum classloadAction {
77 LOAD_INSTANCE = 1, // calling load_instance_class
78 LOAD_SUPER = 2, // loading superclass for this class
79 DEFINE_CLASS = 3 // find_or_define class
80 };
82 // find_and_add returns probe pointer - old or new
83 // If no entry exists, add a placeholder entry and push SeenThread
84 // If entry exists, reuse entry and push SeenThread for classloadAction
85 PlaceholderEntry* find_and_add(int index, unsigned int hash,
86 symbolHandle name, Handle loader,
87 classloadAction action, symbolHandle supername,
88 Thread* thread);
90 void remove_entry(int index, unsigned int hash,
91 symbolHandle name, Handle loader);
93 // Remove placeholder information
94 void find_and_remove(int index, unsigned int hash,
95 symbolHandle name, Handle loader, Thread* thread);
97 // GC support.
98 void oops_do(OopClosure* f);
100 // JVMTI support
101 void entries_do(void f(symbolOop, oop));
103 #ifndef PRODUCT
104 void print();
105 #endif
106 void verify();
107 };
109 // SeenThread objects represent list of threads that are
110 // currently performing a load action on a class.
111 // For class circularity, set before loading a superclass.
112 // For bootclasssearchpath, set before calling load_instance_class.
113 // Defining must be single threaded on a class/classloader basis
114 // For DEFINE_CLASS, the head of the queue owns the
115 // define token and the rest of the threads wait to return the
116 // result the first thread gets.
117 class SeenThread: public CHeapObj {
118 private:
119 Thread *_thread;
120 SeenThread* _stnext;
121 SeenThread* _stprev;
122 public:
123 SeenThread(Thread *thread) {
124 _thread = thread;
125 _stnext = NULL;
126 _stprev = NULL;
127 }
128 Thread* thread() const { return _thread;}
129 void set_thread(Thread *thread) { _thread = thread; }
131 SeenThread* next() const { return _stnext;}
132 void set_next(SeenThread *seen) { _stnext = seen; }
133 void set_prev(SeenThread *seen) { _stprev = seen; }
135 #ifndef PRODUCT
136 void printActionQ() {
137 SeenThread* seen = this;
138 while (seen != NULL) {
139 seen->thread()->print_value();
140 tty->print(", ");
141 seen = seen->next();
142 }
143 }
144 #endif // PRODUCT
145 };
147 // Placeholder objects represent classes currently being loaded.
148 // All threads examining the placeholder table must hold the
149 // SystemDictionary_lock, so we don't need special precautions
150 // on store ordering here.
151 // The system dictionary is the only user of this class.
153 class PlaceholderEntry : public HashtableEntry {
154 friend class VMStructs;
157 private:
158 oop _loader; // initiating loader
159 bool _havesupername; // distinguish between null supername, and unknown
160 symbolOop _supername;
161 Thread* _definer; // owner of define token
162 klassOop _instanceKlass; // instanceKlass from successful define
163 SeenThread* _superThreadQ; // doubly-linked queue of Threads loading a superclass for this class
164 SeenThread* _loadInstanceThreadQ; // loadInstance thread
165 // can be multiple threads if classloader object lock broken by application
166 // or if classloader supports parallel classloading
168 SeenThread* _defineThreadQ; // queue of Threads trying to define this class
169 // including _definer
170 // _definer owns token
171 // queue waits for and returns results from _definer
173 public:
174 // Simple accessors, used only by SystemDictionary
175 symbolOop klass() const { return (symbolOop)literal(); }
176 symbolOop* klass_addr() { return (symbolOop*)literal_addr(); }
178 oop loader() const { return _loader; }
179 void set_loader(oop loader) { _loader = loader; }
180 oop* loader_addr() { return &_loader; }
182 bool havesupername() const { return _havesupername; }
183 void set_havesupername(bool havesupername) { _havesupername = havesupername; }
185 symbolOop supername() const { return _supername; }
186 void set_supername(symbolOop supername) { _supername = supername; }
187 symbolOop* supername_addr() { return &_supername; }
189 Thread* definer() const {return _definer; }
190 void set_definer(Thread* definer) { _definer = definer; }
192 klassOop instanceKlass() const {return _instanceKlass; }
193 void set_instanceKlass(klassOop instanceKlass) { _instanceKlass = instanceKlass; }
194 klassOop* instanceKlass_addr() { return &_instanceKlass; }
196 SeenThread* superThreadQ() const { return _superThreadQ; }
197 void set_superThreadQ(SeenThread* SeenThread) { _superThreadQ = SeenThread; }
199 SeenThread* loadInstanceThreadQ() const { return _loadInstanceThreadQ; }
200 void set_loadInstanceThreadQ(SeenThread* SeenThread) { _loadInstanceThreadQ = SeenThread; }
202 SeenThread* defineThreadQ() const { return _defineThreadQ; }
203 void set_defineThreadQ(SeenThread* SeenThread) { _defineThreadQ = SeenThread; }
205 PlaceholderEntry* next() const {
206 return (PlaceholderEntry*)HashtableEntry::next();
207 }
209 PlaceholderEntry** next_addr() {
210 return (PlaceholderEntry**)HashtableEntry::next_addr();
211 }
213 // Test for equality
214 // Entries are unique for class/classloader name pair
215 bool equals(symbolOop class_name, oop class_loader) const {
216 return (klass() == class_name && loader() == class_loader);
217 }
219 SeenThread* actionToQueue(PlaceholderTable::classloadAction action) {
220 SeenThread* queuehead;
221 switch (action) {
222 case PlaceholderTable::LOAD_INSTANCE:
223 queuehead = _loadInstanceThreadQ;
224 break;
225 case PlaceholderTable::LOAD_SUPER:
226 queuehead = _superThreadQ;
227 break;
228 case PlaceholderTable::DEFINE_CLASS:
229 queuehead = _defineThreadQ;
230 break;
231 default: Unimplemented();
232 }
233 return queuehead;
234 }
236 void set_threadQ(SeenThread* seenthread, PlaceholderTable::classloadAction action) {
237 switch (action) {
238 case PlaceholderTable::LOAD_INSTANCE:
239 _loadInstanceThreadQ = seenthread;
240 break;
241 case PlaceholderTable::LOAD_SUPER:
242 _superThreadQ = seenthread;
243 break;
244 case PlaceholderTable::DEFINE_CLASS:
245 _defineThreadQ = seenthread;
246 break;
247 default: Unimplemented();
248 }
249 return;
250 }
252 bool super_load_in_progress() {
253 return (_superThreadQ != NULL);
254 }
256 bool instance_load_in_progress() {
257 return (_loadInstanceThreadQ != NULL);
258 }
260 bool define_class_in_progress() {
261 return (_defineThreadQ != NULL);
262 }
264 // Doubly-linked list of Threads per action for class/classloader pair
265 // Class circularity support: links in thread before loading superclass
266 // bootstrapsearchpath support: links in a thread before load_instance_class
267 // definers: use as queue of define requestors, including owner of
268 // define token. Appends for debugging of requestor order
269 void add_seen_thread(Thread* thread, PlaceholderTable::classloadAction action) {
270 assert_lock_strong(SystemDictionary_lock);
271 SeenThread* threadEntry = new SeenThread(thread);
272 SeenThread* seen = actionToQueue(action);
274 if (seen == NULL) {
275 set_threadQ(threadEntry, action);
276 return;
277 }
278 SeenThread* next;
279 while ((next = seen->next()) != NULL) {
280 seen = next;
281 }
282 seen->set_next(threadEntry);
283 threadEntry->set_prev(seen);
284 return;
285 }
287 bool check_seen_thread(Thread* thread, PlaceholderTable::classloadAction action) {
288 assert_lock_strong(SystemDictionary_lock);
289 SeenThread* threadQ = actionToQueue(action);
290 SeenThread* seen = threadQ;
291 while (seen) {
292 if (thread == seen->thread()) {
293 return true;
294 }
295 seen = seen->next();
296 }
297 return false;
298 }
300 // returns true if seenthreadQ is now empty
301 // Note, caller must ensure probe still exists while holding
302 // SystemDictionary_lock
303 // ignores if cleanup has already been done
304 // if found, deletes SeenThread
305 bool remove_seen_thread(Thread* thread, PlaceholderTable::classloadAction action) {
306 assert_lock_strong(SystemDictionary_lock);
307 SeenThread* threadQ = actionToQueue(action);
308 SeenThread* seen = threadQ;
309 SeenThread* prev = NULL;
310 while (seen) {
311 if (thread == seen->thread()) {
312 if (prev) {
313 prev->set_next(seen->next());
314 } else {
315 set_threadQ(seen->next(), action);
316 }
317 if (seen->next()) {
318 seen->next()->set_prev(prev);
319 }
320 delete seen;
321 break;
322 }
323 prev = seen;
324 seen = seen->next();
325 }
326 return (actionToQueue(action) == NULL);
327 }
329 // GC support
330 // Applies "f->do_oop" to all root oops in the placeholder table.
331 void oops_do(OopClosure* blk);
333 // Print method doesn't append a cr
334 void print() const PRODUCT_RETURN;
335 void verify() const;
336 };
338 #endif // SHARE_VM_CLASSFILE_PLACEHOLDERS_HPP