src/share/vm/gc_implementation/g1/dirtyCardQueue.cpp

Tue, 13 Apr 2010 13:52:10 -0700

author
jmasa
date
Tue, 13 Apr 2010 13:52:10 -0700
changeset 1822
0bfd3fb24150
parent 1546
44f61c24ddab
child 1907
c18cbe5936b8
permissions
-rw-r--r--

6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
Summary: Ensure a full GC that clears SoftReferences before throwing an out-of-memory
Reviewed-by: ysr, jcoomes

ysr@777 1 /*
xdono@1279 2 * Copyright 2001-2009 Sun Microsystems, Inc. All Rights Reserved.
ysr@777 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
ysr@777 4 *
ysr@777 5 * This code is free software; you can redistribute it and/or modify it
ysr@777 6 * under the terms of the GNU General Public License version 2 only, as
ysr@777 7 * published by the Free Software Foundation.
ysr@777 8 *
ysr@777 9 * This code is distributed in the hope that it will be useful, but WITHOUT
ysr@777 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
ysr@777 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
ysr@777 12 * version 2 for more details (a copy is included in the LICENSE file that
ysr@777 13 * accompanied this code).
ysr@777 14 *
ysr@777 15 * You should have received a copy of the GNU General Public License version
ysr@777 16 * 2 along with this work; if not, write to the Free Software Foundation,
ysr@777 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
ysr@777 18 *
ysr@777 19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
ysr@777 20 * CA 95054 USA or visit www.sun.com if you need additional information or
ysr@777 21 * have any questions.
ysr@777 22 *
ysr@777 23 */
ysr@777 24
ysr@777 25 # include "incls/_precompiled.incl"
ysr@777 26 # include "incls/_dirtyCardQueue.cpp.incl"
ysr@777 27
ysr@777 28 bool DirtyCardQueue::apply_closure(CardTableEntryClosure* cl,
ysr@777 29 bool consume,
ysr@777 30 size_t worker_i) {
ysr@777 31 bool res = true;
ysr@777 32 if (_buf != NULL) {
ysr@777 33 res = apply_closure_to_buffer(cl, _buf, _index, _sz,
ysr@777 34 consume,
ysr@777 35 (int) worker_i);
ysr@777 36 if (res && consume) _index = _sz;
ysr@777 37 }
ysr@777 38 return res;
ysr@777 39 }
ysr@777 40
ysr@777 41 bool DirtyCardQueue::apply_closure_to_buffer(CardTableEntryClosure* cl,
ysr@777 42 void** buf,
ysr@777 43 size_t index, size_t sz,
ysr@777 44 bool consume,
ysr@777 45 int worker_i) {
ysr@777 46 if (cl == NULL) return true;
ysr@777 47 for (size_t i = index; i < sz; i += oopSize) {
ysr@777 48 int ind = byte_index_to_index((int)i);
ysr@777 49 jbyte* card_ptr = (jbyte*)buf[ind];
ysr@777 50 if (card_ptr != NULL) {
ysr@777 51 // Set the entry to null, so we don't do it again (via the test
ysr@777 52 // above) if we reconsider this buffer.
ysr@777 53 if (consume) buf[ind] = NULL;
ysr@777 54 if (!cl->do_card_ptr(card_ptr, worker_i)) return false;
ysr@777 55 }
ysr@777 56 }
ysr@777 57 return true;
ysr@777 58 }
ysr@777 59
ysr@777 60 #ifdef _MSC_VER // the use of 'this' below gets a warning, make it go away
ysr@777 61 #pragma warning( disable:4355 ) // 'this' : used in base member initializer list
ysr@777 62 #endif // _MSC_VER
ysr@777 63
iveresov@1546 64 DirtyCardQueueSet::DirtyCardQueueSet(bool notify_when_complete) :
iveresov@1546 65 PtrQueueSet(notify_when_complete),
ysr@777 66 _closure(NULL),
ysr@777 67 _shared_dirty_card_queue(this, true /*perm*/),
ysr@777 68 _free_ids(NULL),
ysr@777 69 _processed_buffers_mut(0), _processed_buffers_rs_thread(0)
ysr@777 70 {
ysr@777 71 _all_active = true;
ysr@777 72 }
ysr@777 73
iveresov@1230 74 // Determines how many mutator threads can process the buffers in parallel.
ysr@777 75 size_t DirtyCardQueueSet::num_par_ids() {
iveresov@1230 76 return os::processor_count();
ysr@777 77 }
ysr@777 78
ysr@777 79 void DirtyCardQueueSet::initialize(Monitor* cbl_mon, Mutex* fl_lock,
iveresov@1546 80 int process_completed_threshold,
ysr@777 81 int max_completed_queue,
iveresov@1051 82 Mutex* lock, PtrQueueSet* fl_owner) {
iveresov@1546 83 PtrQueueSet::initialize(cbl_mon, fl_lock, process_completed_threshold,
iveresov@1546 84 max_completed_queue, fl_owner);
tonyp@1318 85 set_buffer_size(G1UpdateBufferSize);
ysr@777 86 _shared_dirty_card_queue.set_lock(lock);
ysr@777 87 _free_ids = new FreeIdSet((int) num_par_ids(), _cbl_mon);
ysr@777 88 }
ysr@777 89
ysr@777 90 void DirtyCardQueueSet::handle_zero_index_for_thread(JavaThread* t) {
ysr@777 91 t->dirty_card_queue().handle_zero_index();
ysr@777 92 }
ysr@777 93
ysr@777 94 void DirtyCardQueueSet::set_closure(CardTableEntryClosure* closure) {
ysr@777 95 _closure = closure;
ysr@777 96 }
ysr@777 97
ysr@777 98 void DirtyCardQueueSet::iterate_closure_all_threads(bool consume,
ysr@777 99 size_t worker_i) {
ysr@777 100 assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
ysr@777 101 for(JavaThread* t = Threads::first(); t; t = t->next()) {
ysr@777 102 bool b = t->dirty_card_queue().apply_closure(_closure, consume);
ysr@777 103 guarantee(b, "Should not be interrupted.");
ysr@777 104 }
ysr@777 105 bool b = shared_dirty_card_queue()->apply_closure(_closure,
ysr@777 106 consume,
ysr@777 107 worker_i);
ysr@777 108 guarantee(b, "Should not be interrupted.");
ysr@777 109 }
ysr@777 110
ysr@777 111 bool DirtyCardQueueSet::mut_process_buffer(void** buf) {
ysr@777 112
ysr@777 113 // Used to determine if we had already claimed a par_id
ysr@777 114 // before entering this method.
ysr@777 115 bool already_claimed = false;
ysr@777 116
ysr@777 117 // We grab the current JavaThread.
ysr@777 118 JavaThread* thread = JavaThread::current();
ysr@777 119
ysr@777 120 // We get the the number of any par_id that this thread
ysr@777 121 // might have already claimed.
ysr@777 122 int worker_i = thread->get_claimed_par_id();
ysr@777 123
ysr@777 124 // If worker_i is not -1 then the thread has already claimed
ysr@777 125 // a par_id. We make note of it using the already_claimed value
ysr@777 126 if (worker_i != -1) {
ysr@777 127 already_claimed = true;
ysr@777 128 } else {
ysr@777 129
ysr@777 130 // Otherwise we need to claim a par id
ysr@777 131 worker_i = _free_ids->claim_par_id();
ysr@777 132
ysr@777 133 // And store the par_id value in the thread
ysr@777 134 thread->set_claimed_par_id(worker_i);
ysr@777 135 }
ysr@777 136
ysr@777 137 bool b = false;
ysr@777 138 if (worker_i != -1) {
ysr@777 139 b = DirtyCardQueue::apply_closure_to_buffer(_closure, buf, 0,
ysr@777 140 _sz, true, worker_i);
ysr@777 141 if (b) Atomic::inc(&_processed_buffers_mut);
ysr@777 142
ysr@777 143 // If we had not claimed an id before entering the method
ysr@777 144 // then we must release the id.
ysr@777 145 if (!already_claimed) {
ysr@777 146
ysr@777 147 // we release the id
ysr@777 148 _free_ids->release_par_id(worker_i);
ysr@777 149
ysr@777 150 // and set the claimed_id in the thread to -1
ysr@777 151 thread->set_claimed_par_id(-1);
ysr@777 152 }
ysr@777 153 }
ysr@777 154 return b;
ysr@777 155 }
ysr@777 156
iveresov@1546 157
iveresov@1546 158 BufferNode*
johnc@1525 159 DirtyCardQueueSet::get_completed_buffer(int stop_at) {
iveresov@1546 160 BufferNode* nd = NULL;
ysr@777 161 MutexLockerEx x(_cbl_mon, Mutex::_no_safepoint_check_flag);
ysr@777 162
ysr@777 163 if ((int)_n_completed_buffers <= stop_at) {
ysr@777 164 _process_completed = false;
ysr@777 165 return NULL;
ysr@777 166 }
ysr@777 167
ysr@777 168 if (_completed_buffers_head != NULL) {
ysr@777 169 nd = _completed_buffers_head;
iveresov@1546 170 _completed_buffers_head = nd->next();
ysr@777 171 if (_completed_buffers_head == NULL)
ysr@777 172 _completed_buffers_tail = NULL;
ysr@777 173 _n_completed_buffers--;
iveresov@1546 174 assert(_n_completed_buffers >= 0, "Invariant");
ysr@777 175 }
ysr@777 176 debug_only(assert_completed_buffer_list_len_correct_locked());
ysr@777 177 return nd;
ysr@777 178 }
ysr@777 179
ysr@777 180 bool DirtyCardQueueSet::
ysr@777 181 apply_closure_to_completed_buffer_helper(int worker_i,
iveresov@1546 182 BufferNode* nd) {
ysr@777 183 if (nd != NULL) {
iveresov@1546 184 void **buf = BufferNode::make_buffer_from_node(nd);
iveresov@1546 185 size_t index = nd->index();
ysr@777 186 bool b =
iveresov@1546 187 DirtyCardQueue::apply_closure_to_buffer(_closure, buf,
iveresov@1546 188 index, _sz,
ysr@777 189 true, worker_i);
ysr@777 190 if (b) {
ysr@777 191 deallocate_buffer(buf);
ysr@777 192 return true; // In normal case, go on to next buffer.
ysr@777 193 } else {
iveresov@1546 194 enqueue_complete_buffer(buf, index);
ysr@777 195 return false;
ysr@777 196 }
ysr@777 197 } else {
ysr@777 198 return false;
ysr@777 199 }
ysr@777 200 }
ysr@777 201
ysr@777 202 bool DirtyCardQueueSet::apply_closure_to_completed_buffer(int worker_i,
ysr@777 203 int stop_at,
johnc@1525 204 bool during_pause)
ysr@777 205 {
johnc@1525 206 assert(!during_pause || stop_at == 0, "Should not leave any completed buffers during a pause");
iveresov@1546 207 BufferNode* nd = get_completed_buffer(stop_at);
ysr@777 208 bool res = apply_closure_to_completed_buffer_helper(worker_i, nd);
iveresov@1229 209 if (res) Atomic::inc(&_processed_buffers_rs_thread);
ysr@777 210 return res;
ysr@777 211 }
ysr@777 212
ysr@777 213 void DirtyCardQueueSet::apply_closure_to_all_completed_buffers() {
iveresov@1546 214 BufferNode* nd = _completed_buffers_head;
ysr@777 215 while (nd != NULL) {
ysr@777 216 bool b =
iveresov@1546 217 DirtyCardQueue::apply_closure_to_buffer(_closure,
iveresov@1546 218 BufferNode::make_buffer_from_node(nd),
iveresov@1546 219 0, _sz, false);
ysr@777 220 guarantee(b, "Should not stop early.");
iveresov@1546 221 nd = nd->next();
ysr@777 222 }
ysr@777 223 }
ysr@777 224
ysr@777 225 void DirtyCardQueueSet::abandon_logs() {
ysr@777 226 assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
iveresov@1546 227 BufferNode* buffers_to_delete = NULL;
ysr@777 228 {
ysr@777 229 MutexLockerEx x(_cbl_mon, Mutex::_no_safepoint_check_flag);
ysr@777 230 while (_completed_buffers_head != NULL) {
iveresov@1546 231 BufferNode* nd = _completed_buffers_head;
iveresov@1546 232 _completed_buffers_head = nd->next();
iveresov@1546 233 nd->set_next(buffers_to_delete);
ysr@777 234 buffers_to_delete = nd;
ysr@777 235 }
ysr@777 236 _n_completed_buffers = 0;
ysr@777 237 _completed_buffers_tail = NULL;
ysr@777 238 debug_only(assert_completed_buffer_list_len_correct_locked());
ysr@777 239 }
ysr@777 240 while (buffers_to_delete != NULL) {
iveresov@1546 241 BufferNode* nd = buffers_to_delete;
iveresov@1546 242 buffers_to_delete = nd->next();
iveresov@1546 243 deallocate_buffer(BufferNode::make_buffer_from_node(nd));
ysr@777 244 }
ysr@777 245 // Since abandon is done only at safepoints, we can safely manipulate
ysr@777 246 // these queues.
ysr@777 247 for (JavaThread* t = Threads::first(); t; t = t->next()) {
ysr@777 248 t->dirty_card_queue().reset();
ysr@777 249 }
ysr@777 250 shared_dirty_card_queue()->reset();
ysr@777 251 }
ysr@777 252
ysr@777 253
ysr@777 254 void DirtyCardQueueSet::concatenate_logs() {
ysr@777 255 // Iterate over all the threads, if we find a partial log add it to
ysr@777 256 // the global list of logs. Temporarily turn off the limit on the number
ysr@777 257 // of outstanding buffers.
ysr@777 258 int save_max_completed_queue = _max_completed_queue;
ysr@777 259 _max_completed_queue = max_jint;
ysr@777 260 assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
ysr@777 261 for (JavaThread* t = Threads::first(); t; t = t->next()) {
ysr@777 262 DirtyCardQueue& dcq = t->dirty_card_queue();
ysr@777 263 if (dcq.size() != 0) {
ysr@777 264 void **buf = t->dirty_card_queue().get_buf();
ysr@777 265 // We must NULL out the unused entries, then enqueue.
ysr@777 266 for (size_t i = 0; i < t->dirty_card_queue().get_index(); i += oopSize) {
ysr@777 267 buf[PtrQueue::byte_index_to_index((int)i)] = NULL;
ysr@777 268 }
ysr@777 269 enqueue_complete_buffer(dcq.get_buf(), dcq.get_index());
ysr@777 270 dcq.reinitialize();
ysr@777 271 }
ysr@777 272 }
ysr@777 273 if (_shared_dirty_card_queue.size() != 0) {
ysr@777 274 enqueue_complete_buffer(_shared_dirty_card_queue.get_buf(),
ysr@777 275 _shared_dirty_card_queue.get_index());
ysr@777 276 _shared_dirty_card_queue.reinitialize();
ysr@777 277 }
ysr@777 278 // Restore the completed buffer queue limit.
ysr@777 279 _max_completed_queue = save_max_completed_queue;
ysr@777 280 }

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