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/heapRegionRemSet.hpp"
28 #include "runtime/atomic.hpp"
29 #include "runtime/mutexLocker.hpp"
30 #include "runtime/safepoint.hpp"
31 #include "runtime/thread.hpp"
32 #include "utilities/workgroup.hpp"
33 #ifdef TARGET_OS_FAMILY_linux
34 # include "thread_linux.inline.hpp"
35 #endif
36 #ifdef TARGET_OS_FAMILY_solaris
37 # include "thread_solaris.inline.hpp"
38 #endif
39 #ifdef TARGET_OS_FAMILY_windows
40 # include "thread_windows.inline.hpp"
41 #endif
42
43 bool DirtyCardQueue::apply_closure(CardTableEntryClosure* cl,
44 bool consume,
45 size_t worker_i) {
46 bool res = true;
47 if (_buf != NULL) {
48 res = apply_closure_to_buffer(cl, _buf, _index, _sz,
49 consume,
50 (int) worker_i);
51 if (res && consume) _index = _sz;
52 }
53 return res;
54 }
55
56 bool DirtyCardQueue::apply_closure_to_buffer(CardTableEntryClosure* cl,
57 void** buf,
58 size_t index, size_t sz,
59 bool consume,
60 int worker_i) {
61 if (cl == NULL) return true;
62 for (size_t i = index; i < sz; i += oopSize) {
63 int ind = byte_index_to_index((int)i);
64 jbyte* card_ptr = (jbyte*)buf[ind];
65 if (card_ptr != NULL) {
66 // Set the entry to null, so we don't do it again (via the test
67 // above) if we reconsider this buffer.
68 if (consume) buf[ind] = NULL;
69 if (!cl->do_card_ptr(card_ptr, worker_i)) return false;
70 }
71 }
72 return true;
73 }
74
75 #ifdef _MSC_VER // the use of 'this' below gets a warning, make it go away
76 #pragma warning( disable:4355 ) // 'this' : used in base member initializer list
77 #endif // _MSC_VER
78
79 DirtyCardQueueSet::DirtyCardQueueSet(bool notify_when_complete) :
80 PtrQueueSet(notify_when_complete),
81 _closure(NULL),
82 _shared_dirty_card_queue(this, true /*perm*/),
83 _free_ids(NULL),
84 _processed_buffers_mut(0), _processed_buffers_rs_thread(0)
85 {
86 _all_active = true;
87 }
88
89 // Determines how many mutator threads can process the buffers in parallel.
90 size_t DirtyCardQueueSet::num_par_ids() {
91 return os::processor_count();
92 }
93
94 void DirtyCardQueueSet::initialize(Monitor* cbl_mon, Mutex* fl_lock,
95 int process_completed_threshold,
96 int max_completed_queue,
97 Mutex* lock, PtrQueueSet* fl_owner) {
98 PtrQueueSet::initialize(cbl_mon, fl_lock, process_completed_threshold,
99 max_completed_queue, fl_owner);
100 set_buffer_size(G1UpdateBufferSize);
101 _shared_dirty_card_queue.set_lock(lock);
102 _free_ids = new FreeIdSet((int) num_par_ids(), _cbl_mon);
103 }
104
105 void DirtyCardQueueSet::handle_zero_index_for_thread(JavaThread* t) {
106 t->dirty_card_queue().handle_zero_index();
107 }
108
109 void DirtyCardQueueSet::set_closure(CardTableEntryClosure* closure) {
110 _closure = closure;
111 }
112
113 void DirtyCardQueueSet::iterate_closure_all_threads(bool consume,
114 size_t worker_i) {
115 assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
116 for(JavaThread* t = Threads::first(); t; t = t->next()) {
117 bool b = t->dirty_card_queue().apply_closure(_closure, consume);
118 guarantee(b, "Should not be interrupted.");
119 }
120 bool b = shared_dirty_card_queue()->apply_closure(_closure,
121 consume,
122 worker_i);
123 guarantee(b, "Should not be interrupted.");
124 }
125
126 bool DirtyCardQueueSet::mut_process_buffer(void** buf) {
127
128 // Used to determine if we had already claimed a par_id
129 // before entering this method.
130 bool already_claimed = false;
131
132 // We grab the current JavaThread.
133 JavaThread* thread = JavaThread::current();
134
135 // We get the the number of any par_id that this thread
136 // might have already claimed.
137 int worker_i = thread->get_claimed_par_id();
138
139 // If worker_i is not -1 then the thread has already claimed
140 // a par_id. We make note of it using the already_claimed value
141 if (worker_i != -1) {
142 already_claimed = true;
143 } else {
144
145 // Otherwise we need to claim a par id
146 worker_i = _free_ids->claim_par_id();
147
148 // And store the par_id value in the thread
149 thread->set_claimed_par_id(worker_i);
150 }
151
152 bool b = false;
153 if (worker_i != -1) {
154 b = DirtyCardQueue::apply_closure_to_buffer(_closure, buf, 0,
155 _sz, true, worker_i);
156 if (b) Atomic::inc(&_processed_buffers_mut);
157
158 // If we had not claimed an id before entering the method
159 // then we must release the id.
160 if (!already_claimed) {
161
162 // we release the id
163 _free_ids->release_par_id(worker_i);
164
165 // and set the claimed_id in the thread to -1
166 thread->set_claimed_par_id(-1);
167 }
168 }
169 return b;
170 }
171
172
173 BufferNode*
174 DirtyCardQueueSet::get_completed_buffer(int stop_at) {
175 BufferNode* nd = NULL;
176 MutexLockerEx x(_cbl_mon, Mutex::_no_safepoint_check_flag);
177
178 if ((int)_n_completed_buffers <= stop_at) {
179 _process_completed = false;
180 return NULL;
181 }
182
183 if (_completed_buffers_head != NULL) {
184 nd = _completed_buffers_head;
185 _completed_buffers_head = nd->next();
186 if (_completed_buffers_head == NULL)
187 _completed_buffers_tail = NULL;
188 _n_completed_buffers--;
189 assert(_n_completed_buffers >= 0, "Invariant");
190 }
191 debug_only(assert_completed_buffer_list_len_correct_locked());
192 return nd;
193 }
194
195 bool DirtyCardQueueSet::
196 apply_closure_to_completed_buffer_helper(CardTableEntryClosure* cl,
197 int worker_i,
198 BufferNode* nd) {
199 if (nd != NULL) {
200 void **buf = BufferNode::make_buffer_from_node(nd);
201 size_t index = nd->index();
202 bool b =
203 DirtyCardQueue::apply_closure_to_buffer(cl, buf,
204 index, _sz,
205 true, worker_i);
206 if (b) {
207 deallocate_buffer(buf);
208 return true; // In normal case, go on to next buffer.
209 } else {
210 enqueue_complete_buffer(buf, index);
211 return false;
212 }
213 } else {
214 return false;
215 }
216 }
217
218 bool DirtyCardQueueSet::apply_closure_to_completed_buffer(CardTableEntryClosure* cl,
219 int worker_i,
220 int stop_at,
221 bool during_pause) {
222 assert(!during_pause || stop_at == 0, "Should not leave any completed buffers during a pause");
223 BufferNode* nd = get_completed_buffer(stop_at);
224 bool res = apply_closure_to_completed_buffer_helper(cl, worker_i, nd);
225 if (res) Atomic::inc(&_processed_buffers_rs_thread);
226 return res;
227 }
228
229 bool DirtyCardQueueSet::apply_closure_to_completed_buffer(int worker_i,
230 int stop_at,
231 bool during_pause) {
232 return apply_closure_to_completed_buffer(_closure, worker_i,
233 stop_at, during_pause);
234 }
235
236 void DirtyCardQueueSet::apply_closure_to_all_completed_buffers() {
237 BufferNode* nd = _completed_buffers_head;
238 while (nd != NULL) {
239 bool b =
240 DirtyCardQueue::apply_closure_to_buffer(_closure,
241 BufferNode::make_buffer_from_node(nd),
242 0, _sz, false);
243 guarantee(b, "Should not stop early.");
244 nd = nd->next();
245 }
246 }
247
248 // Deallocates any completed log buffers
249 void DirtyCardQueueSet::clear() {
250 BufferNode* buffers_to_delete = NULL;
251 {
252 MutexLockerEx x(_cbl_mon, Mutex::_no_safepoint_check_flag);
253 while (_completed_buffers_head != NULL) {
254 BufferNode* nd = _completed_buffers_head;
255 _completed_buffers_head = nd->next();
256 nd->set_next(buffers_to_delete);
257 buffers_to_delete = nd;
258 }
259 _n_completed_buffers = 0;
260 _completed_buffers_tail = NULL;
261 debug_only(assert_completed_buffer_list_len_correct_locked());
262 }
263 while (buffers_to_delete != NULL) {
264 BufferNode* nd = buffers_to_delete;
265 buffers_to_delete = nd->next();
266 deallocate_buffer(BufferNode::make_buffer_from_node(nd));
267 }
268
269 }
270
271 void DirtyCardQueueSet::abandon_logs() {
272 assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
273 clear();
274 // Since abandon is done only at safepoints, we can safely manipulate
275 // these queues.
276 for (JavaThread* t = Threads::first(); t; t = t->next()) {
277 t->dirty_card_queue().reset();
278 }
279 shared_dirty_card_queue()->reset();
280 }
281
282
283 void DirtyCardQueueSet::concatenate_logs() {
284 // Iterate over all the threads, if we find a partial log add it to
285 // the global list of logs. Temporarily turn off the limit on the number
286 // of outstanding buffers.
287 int save_max_completed_queue = _max_completed_queue;
288 _max_completed_queue = max_jint;
289 assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
290 for (JavaThread* t = Threads::first(); t; t = t->next()) {
291 DirtyCardQueue& dcq = t->dirty_card_queue();
292 if (dcq.size() != 0) {
293 void **buf = t->dirty_card_queue().get_buf();
294 // We must NULL out the unused entries, then enqueue.
295 for (size_t i = 0; i < t->dirty_card_queue().get_index(); i += oopSize) {
296 buf[PtrQueue::byte_index_to_index((int)i)] = NULL;
297 }
298 enqueue_complete_buffer(dcq.get_buf(), dcq.get_index());
299 dcq.reinitialize();
300 }
301 }
302 if (_shared_dirty_card_queue.size() != 0) {
303 enqueue_complete_buffer(_shared_dirty_card_queue.get_buf(),
304 _shared_dirty_card_queue.get_index());
305 _shared_dirty_card_queue.reinitialize();
306 }
307 // Restore the completed buffer queue limit.
308 _max_completed_queue = save_max_completed_queue;
309 }