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 "precompiled.hpp"
26 #include "gc_implementation/g1/dirtyCardQueue.hpp"
27 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
28 #include "gc_implementation/g1/heapRegionRemSet.hpp"
29 #include "runtime/atomic.hpp"
30 #include "runtime/mutexLocker.hpp"
31 #include "runtime/safepoint.hpp"
32 #include "runtime/thread.inline.hpp"
33 #include "utilities/workgroup.hpp"
34
35 bool DirtyCardQueue::apply_closure(CardTableEntryClosure* cl,
36 bool consume,
37 uint worker_i) {
38 bool res = true;
39 if (_buf != NULL) {
40 res = apply_closure_to_buffer(cl, _buf, _index, _sz,
41 consume,
42 worker_i);
43 if (res && consume) _index = _sz;
44 }
45 return res;
46 }
47
48 bool DirtyCardQueue::apply_closure_to_buffer(CardTableEntryClosure* cl,
49 void** buf,
50 size_t index, size_t sz,
51 bool consume,
52 uint worker_i) {
53 if (cl == NULL) return true;
54 for (size_t i = index; i < sz; i += oopSize) {
55 int ind = byte_index_to_index((int)i);
56 jbyte* card_ptr = (jbyte*)buf[ind];
57 if (card_ptr != NULL) {
58 // Set the entry to null, so we don't do it again (via the test
59 // above) if we reconsider this buffer.
60 if (consume) buf[ind] = NULL;
61 if (!cl->do_card_ptr(card_ptr, worker_i)) return false;
62 }
63 }
64 return true;
65 }
66
67 #ifdef _MSC_VER // the use of 'this' below gets a warning, make it go away
68 #pragma warning( disable:4355 ) // 'this' : used in base member initializer list
69 #endif // _MSC_VER
70
71 DirtyCardQueueSet::DirtyCardQueueSet(bool notify_when_complete) :
72 PtrQueueSet(notify_when_complete),
73 _closure(NULL),
74 _shared_dirty_card_queue(this, true /*perm*/),
75 _free_ids(NULL),
76 _processed_buffers_mut(0), _processed_buffers_rs_thread(0)
77 {
78 _all_active = true;
79 }
80
81 // Determines how many mutator threads can process the buffers in parallel.
82 uint DirtyCardQueueSet::num_par_ids() {
83 return (uint)os::processor_count();
84 }
85
86 void DirtyCardQueueSet::initialize(Monitor* cbl_mon, Mutex* fl_lock,
87 int process_completed_threshold,
88 int max_completed_queue,
89 Mutex* lock, PtrQueueSet* fl_owner) {
90 PtrQueueSet::initialize(cbl_mon, fl_lock, process_completed_threshold,
91 max_completed_queue, fl_owner);
92 set_buffer_size(G1UpdateBufferSize);
93 _shared_dirty_card_queue.set_lock(lock);
94 _free_ids = new FreeIdSet((int) num_par_ids(), _cbl_mon);
95 }
96
97 void DirtyCardQueueSet::handle_zero_index_for_thread(JavaThread* t) {
98 t->dirty_card_queue().handle_zero_index();
99 }
100
101 void DirtyCardQueueSet::set_closure(CardTableEntryClosure* closure) {
102 _closure = closure;
103 }
104
105 void DirtyCardQueueSet::iterate_closure_all_threads(bool consume,
106 uint worker_i) {
107 assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
108 for(JavaThread* t = Threads::first(); t; t = t->next()) {
109 bool b = t->dirty_card_queue().apply_closure(_closure, consume);
110 guarantee(b, "Should not be interrupted.");
111 }
112 bool b = shared_dirty_card_queue()->apply_closure(_closure,
113 consume,
114 worker_i);
115 guarantee(b, "Should not be interrupted.");
116 }
117
118 bool DirtyCardQueueSet::mut_process_buffer(void** buf) {
119
120 // Used to determine if we had already claimed a par_id
121 // before entering this method.
122 bool already_claimed = false;
123
124 // We grab the current JavaThread.
125 JavaThread* thread = JavaThread::current();
126
127 // We get the the number of any par_id that this thread
128 // might have already claimed.
129 uint worker_i = thread->get_claimed_par_id();
130
131 // If worker_i is not UINT_MAX then the thread has already claimed
132 // a par_id. We make note of it using the already_claimed value
133 if (worker_i != UINT_MAX) {
134 already_claimed = true;
135 } else {
136
137 // Otherwise we need to claim a par id
138 worker_i = _free_ids->claim_par_id();
139
140 // And store the par_id value in the thread
141 thread->set_claimed_par_id(worker_i);
142 }
143
144 bool b = false;
145 if (worker_i != UINT_MAX) {
146 b = DirtyCardQueue::apply_closure_to_buffer(_closure, buf, 0,
147 _sz, true, worker_i);
148 if (b) Atomic::inc(&_processed_buffers_mut);
149
150 // If we had not claimed an id before entering the method
151 // then we must release the id.
152 if (!already_claimed) {
153
154 // we release the id
155 _free_ids->release_par_id(worker_i);
156
157 // and set the claimed_id in the thread to UINT_MAX
158 thread->set_claimed_par_id(UINT_MAX);
159 }
160 }
161 return b;
162 }
163
164
165 BufferNode*
166 DirtyCardQueueSet::get_completed_buffer(int stop_at) {
167 BufferNode* nd = NULL;
168 MutexLockerEx x(_cbl_mon, Mutex::_no_safepoint_check_flag);
169
170 if ((int)_n_completed_buffers <= stop_at) {
171 _process_completed = false;
172 return NULL;
173 }
174
175 if (_completed_buffers_head != NULL) {
176 nd = _completed_buffers_head;
177 _completed_buffers_head = nd->next();
178 if (_completed_buffers_head == NULL)
179 _completed_buffers_tail = NULL;
180 _n_completed_buffers--;
181 assert(_n_completed_buffers >= 0, "Invariant");
182 }
183 debug_only(assert_completed_buffer_list_len_correct_locked());
184 return nd;
185 }
186
187 bool DirtyCardQueueSet::
188 apply_closure_to_completed_buffer_helper(CardTableEntryClosure* cl,
189 uint worker_i,
190 BufferNode* nd) {
191 if (nd != NULL) {
192 void **buf = BufferNode::make_buffer_from_node(nd);
193 size_t index = nd->index();
194 bool b =
195 DirtyCardQueue::apply_closure_to_buffer(cl, buf,
196 index, _sz,
197 true, worker_i);
198 if (b) {
199 deallocate_buffer(buf);
200 return true; // In normal case, go on to next buffer.
201 } else {
202 enqueue_complete_buffer(buf, index);
203 return false;
204 }
205 } else {
206 return false;
207 }
208 }
209
210 bool DirtyCardQueueSet::apply_closure_to_completed_buffer(CardTableEntryClosure* cl,
211 uint worker_i,
212 int stop_at,
213 bool during_pause) {
214 assert(!during_pause || stop_at == 0, "Should not leave any completed buffers during a pause");
215 BufferNode* nd = get_completed_buffer(stop_at);
216 bool res = apply_closure_to_completed_buffer_helper(cl, worker_i, nd);
217 if (res) Atomic::inc(&_processed_buffers_rs_thread);
218 return res;
219 }
220
221 bool DirtyCardQueueSet::apply_closure_to_completed_buffer(uint worker_i,
222 int stop_at,
223 bool during_pause) {
224 return apply_closure_to_completed_buffer(_closure, worker_i,
225 stop_at, during_pause);
226 }
227
228 void DirtyCardQueueSet::apply_closure_to_all_completed_buffers() {
229 BufferNode* nd = _completed_buffers_head;
230 while (nd != NULL) {
231 bool b =
232 DirtyCardQueue::apply_closure_to_buffer(_closure,
233 BufferNode::make_buffer_from_node(nd),
234 0, _sz, false);
235 guarantee(b, "Should not stop early.");
236 nd = nd->next();
237 }
238 }
239
240 // Deallocates any completed log buffers
241 void DirtyCardQueueSet::clear() {
242 BufferNode* buffers_to_delete = NULL;
243 {
244 MutexLockerEx x(_cbl_mon, Mutex::_no_safepoint_check_flag);
245 while (_completed_buffers_head != NULL) {
246 BufferNode* nd = _completed_buffers_head;
247 _completed_buffers_head = nd->next();
248 nd->set_next(buffers_to_delete);
249 buffers_to_delete = nd;
250 }
251 _n_completed_buffers = 0;
252 _completed_buffers_tail = NULL;
253 debug_only(assert_completed_buffer_list_len_correct_locked());
254 }
255 while (buffers_to_delete != NULL) {
256 BufferNode* nd = buffers_to_delete;
257 buffers_to_delete = nd->next();
258 deallocate_buffer(BufferNode::make_buffer_from_node(nd));
259 }
260
261 }
262
263 void DirtyCardQueueSet::abandon_logs() {
264 assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
265 clear();
266 // Since abandon is done only at safepoints, we can safely manipulate
267 // these queues.
268 for (JavaThread* t = Threads::first(); t; t = t->next()) {
269 t->dirty_card_queue().reset();
270 }
271 shared_dirty_card_queue()->reset();
272 }
273
274
275 void DirtyCardQueueSet::concatenate_logs() {
276 // Iterate over all the threads, if we find a partial log add it to
277 // the global list of logs. Temporarily turn off the limit on the number
278 // of outstanding buffers.
279 int save_max_completed_queue = _max_completed_queue;
280 _max_completed_queue = max_jint;
281 assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
282 for (JavaThread* t = Threads::first(); t; t = t->next()) {
283 DirtyCardQueue& dcq = t->dirty_card_queue();
284 if (dcq.size() != 0) {
285 void **buf = t->dirty_card_queue().get_buf();
286 // We must NULL out the unused entries, then enqueue.
287 for (size_t i = 0; i < t->dirty_card_queue().get_index(); i += oopSize) {
288 buf[PtrQueue::byte_index_to_index((int)i)] = NULL;
289 }
290 enqueue_complete_buffer(dcq.get_buf(), dcq.get_index());
291 dcq.reinitialize();
292 }
293 }
294 if (_shared_dirty_card_queue.size() != 0) {
295 enqueue_complete_buffer(_shared_dirty_card_queue.get_buf(),
296 _shared_dirty_card_queue.get_index());
297 _shared_dirty_card_queue.reinitialize();
298 }
299 // Restore the completed buffer queue limit.
300 _max_completed_queue = save_max_completed_queue;
301 }