1 /*
2 * Copyright (c) 2001, 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 */
24
25 # include "incls/_precompiled.incl"
26 # include "incls/_dirtyCardQueue.cpp.incl"
27
28 bool DirtyCardQueue::apply_closure(CardTableEntryClosure* cl,
29 bool consume,
30 size_t worker_i) {
31 bool res = true;
32 if (_buf != NULL) {
33 res = apply_closure_to_buffer(cl, _buf, _index, _sz,
34 consume,
35 (int) worker_i);
36 if (res && consume) _index = _sz;
37 }
38 return res;
39 }
40
41 bool DirtyCardQueue::apply_closure_to_buffer(CardTableEntryClosure* cl,
42 void** buf,
43 size_t index, size_t sz,
44 bool consume,
45 int worker_i) {
46 if (cl == NULL) return true;
47 for (size_t i = index; i < sz; i += oopSize) {
48 int ind = byte_index_to_index((int)i);
49 jbyte* card_ptr = (jbyte*)buf[ind];
50 if (card_ptr != NULL) {
51 // Set the entry to null, so we don't do it again (via the test
52 // above) if we reconsider this buffer.
53 if (consume) buf[ind] = NULL;
54 if (!cl->do_card_ptr(card_ptr, worker_i)) return false;
55 }
56 }
57 return true;
58 }
59
60 #ifdef _MSC_VER // the use of 'this' below gets a warning, make it go away
61 #pragma warning( disable:4355 ) // 'this' : used in base member initializer list
62 #endif // _MSC_VER
63
64 DirtyCardQueueSet::DirtyCardQueueSet(bool notify_when_complete) :
65 PtrQueueSet(notify_when_complete),
66 _closure(NULL),
67 _shared_dirty_card_queue(this, true /*perm*/),
68 _free_ids(NULL),
69 _processed_buffers_mut(0), _processed_buffers_rs_thread(0)
70 {
71 _all_active = true;
72 }
73
74 // Determines how many mutator threads can process the buffers in parallel.
75 size_t DirtyCardQueueSet::num_par_ids() {
76 return os::processor_count();
77 }
78
79 void DirtyCardQueueSet::initialize(Monitor* cbl_mon, Mutex* fl_lock,
80 int process_completed_threshold,
81 int max_completed_queue,
82 Mutex* lock, PtrQueueSet* fl_owner) {
83 PtrQueueSet::initialize(cbl_mon, fl_lock, process_completed_threshold,
84 max_completed_queue, fl_owner);
85 set_buffer_size(G1UpdateBufferSize);
86 _shared_dirty_card_queue.set_lock(lock);
87 _free_ids = new FreeIdSet((int) num_par_ids(), _cbl_mon);
88 }
89
90 void DirtyCardQueueSet::handle_zero_index_for_thread(JavaThread* t) {
91 t->dirty_card_queue().handle_zero_index();
92 }
93
94 void DirtyCardQueueSet::set_closure(CardTableEntryClosure* closure) {
95 _closure = closure;
96 }
97
98 void DirtyCardQueueSet::iterate_closure_all_threads(bool consume,
99 size_t worker_i) {
100 assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
101 for(JavaThread* t = Threads::first(); t; t = t->next()) {
102 bool b = t->dirty_card_queue().apply_closure(_closure, consume);
103 guarantee(b, "Should not be interrupted.");
104 }
105 bool b = shared_dirty_card_queue()->apply_closure(_closure,
106 consume,
107 worker_i);
108 guarantee(b, "Should not be interrupted.");
109 }
110
111 bool DirtyCardQueueSet::mut_process_buffer(void** buf) {
112
113 // Used to determine if we had already claimed a par_id
114 // before entering this method.
115 bool already_claimed = false;
116
117 // We grab the current JavaThread.
118 JavaThread* thread = JavaThread::current();
119
120 // We get the the number of any par_id that this thread
121 // might have already claimed.
122 int worker_i = thread->get_claimed_par_id();
123
124 // If worker_i is not -1 then the thread has already claimed
125 // a par_id. We make note of it using the already_claimed value
126 if (worker_i != -1) {
127 already_claimed = true;
128 } else {
129
130 // Otherwise we need to claim a par id
131 worker_i = _free_ids->claim_par_id();
132
133 // And store the par_id value in the thread
134 thread->set_claimed_par_id(worker_i);
135 }
136
137 bool b = false;
138 if (worker_i != -1) {
139 b = DirtyCardQueue::apply_closure_to_buffer(_closure, buf, 0,
140 _sz, true, worker_i);
141 if (b) Atomic::inc(&_processed_buffers_mut);
142
143 // If we had not claimed an id before entering the method
144 // then we must release the id.
145 if (!already_claimed) {
146
147 // we release the id
148 _free_ids->release_par_id(worker_i);
149
150 // and set the claimed_id in the thread to -1
151 thread->set_claimed_par_id(-1);
152 }
153 }
154 return b;
155 }
156
157
158 BufferNode*
159 DirtyCardQueueSet::get_completed_buffer(int stop_at) {
160 BufferNode* nd = NULL;
161 MutexLockerEx x(_cbl_mon, Mutex::_no_safepoint_check_flag);
162
163 if ((int)_n_completed_buffers <= stop_at) {
164 _process_completed = false;
165 return NULL;
166 }
167
168 if (_completed_buffers_head != NULL) {
169 nd = _completed_buffers_head;
170 _completed_buffers_head = nd->next();
171 if (_completed_buffers_head == NULL)
172 _completed_buffers_tail = NULL;
173 _n_completed_buffers--;
174 assert(_n_completed_buffers >= 0, "Invariant");
175 }
176 debug_only(assert_completed_buffer_list_len_correct_locked());
177 return nd;
178 }
179
180 bool DirtyCardQueueSet::
181 apply_closure_to_completed_buffer_helper(CardTableEntryClosure* cl,
182 int worker_i,
183 BufferNode* nd) {
184 if (nd != NULL) {
185 void **buf = BufferNode::make_buffer_from_node(nd);
186 size_t index = nd->index();
187 bool b =
188 DirtyCardQueue::apply_closure_to_buffer(cl, buf,
189 index, _sz,
190 true, worker_i);
191 if (b) {
192 deallocate_buffer(buf);
193 return true; // In normal case, go on to next buffer.
194 } else {
195 enqueue_complete_buffer(buf, index);
196 return false;
197 }
198 } else {
199 return false;
200 }
201 }
202
203 bool DirtyCardQueueSet::apply_closure_to_completed_buffer(CardTableEntryClosure* cl,
204 int worker_i,
205 int stop_at,
206 bool during_pause) {
207 assert(!during_pause || stop_at == 0, "Should not leave any completed buffers during a pause");
208 BufferNode* nd = get_completed_buffer(stop_at);
209 bool res = apply_closure_to_completed_buffer_helper(cl, worker_i, nd);
210 if (res) Atomic::inc(&_processed_buffers_rs_thread);
211 return res;
212 }
213
214 bool DirtyCardQueueSet::apply_closure_to_completed_buffer(int worker_i,
215 int stop_at,
216 bool during_pause) {
217 return apply_closure_to_completed_buffer(_closure, worker_i,
218 stop_at, during_pause);
219 }
220
221 void DirtyCardQueueSet::apply_closure_to_all_completed_buffers() {
222 BufferNode* nd = _completed_buffers_head;
223 while (nd != NULL) {
224 bool b =
225 DirtyCardQueue::apply_closure_to_buffer(_closure,
226 BufferNode::make_buffer_from_node(nd),
227 0, _sz, false);
228 guarantee(b, "Should not stop early.");
229 nd = nd->next();
230 }
231 }
232
233 // Deallocates any completed log buffers
234 void DirtyCardQueueSet::clear() {
235 BufferNode* buffers_to_delete = NULL;
236 {
237 MutexLockerEx x(_cbl_mon, Mutex::_no_safepoint_check_flag);
238 while (_completed_buffers_head != NULL) {
239 BufferNode* nd = _completed_buffers_head;
240 _completed_buffers_head = nd->next();
241 nd->set_next(buffers_to_delete);
242 buffers_to_delete = nd;
243 }
244 _n_completed_buffers = 0;
245 _completed_buffers_tail = NULL;
246 debug_only(assert_completed_buffer_list_len_correct_locked());
247 }
248 while (buffers_to_delete != NULL) {
249 BufferNode* nd = buffers_to_delete;
250 buffers_to_delete = nd->next();
251 deallocate_buffer(BufferNode::make_buffer_from_node(nd));
252 }
253
254 }
255
256 void DirtyCardQueueSet::abandon_logs() {
257 assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
258 clear();
259 // Since abandon is done only at safepoints, we can safely manipulate
260 // these queues.
261 for (JavaThread* t = Threads::first(); t; t = t->next()) {
262 t->dirty_card_queue().reset();
263 }
264 shared_dirty_card_queue()->reset();
265 }
266
267
268 void DirtyCardQueueSet::concatenate_logs() {
269 // Iterate over all the threads, if we find a partial log add it to
270 // the global list of logs. Temporarily turn off the limit on the number
271 // of outstanding buffers.
272 int save_max_completed_queue = _max_completed_queue;
273 _max_completed_queue = max_jint;
274 assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
275 for (JavaThread* t = Threads::first(); t; t = t->next()) {
276 DirtyCardQueue& dcq = t->dirty_card_queue();
277 if (dcq.size() != 0) {
278 void **buf = t->dirty_card_queue().get_buf();
279 // We must NULL out the unused entries, then enqueue.
280 for (size_t i = 0; i < t->dirty_card_queue().get_index(); i += oopSize) {
281 buf[PtrQueue::byte_index_to_index((int)i)] = NULL;
282 }
283 enqueue_complete_buffer(dcq.get_buf(), dcq.get_index());
284 dcq.reinitialize();
285 }
286 }
287 if (_shared_dirty_card_queue.size() != 0) {
288 enqueue_complete_buffer(_shared_dirty_card_queue.get_buf(),
289 _shared_dirty_card_queue.get_index());
290 _shared_dirty_card_queue.reinitialize();
291 }
292 // Restore the completed buffer queue limit.
293 _max_completed_queue = save_max_completed_queue;
294 }