1 /* 2 * Copyright (c) 2001, 2011, 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/g1SATBCardTableModRefBS.hpp" 27 #include "gc_implementation/g1/heapRegion.hpp" 28 #include "gc_implementation/g1/satbQueue.hpp" 29 #include "runtime/mutexLocker.hpp" 30 #include "runtime/thread.inline.hpp" 31 32 G1SATBCardTableModRefBS::G1SATBCardTableModRefBS(MemRegion whole_heap, 33 int max_covered_regions) : 34 CardTableModRefBSForCTRS(whole_heap, max_covered_regions) 35 { 36 _kind = G1SATBCT; 37 } 38 39 40 void G1SATBCardTableModRefBS::enqueue(oop pre_val) { 41 // Nulls should have been already filtered. 42 assert(pre_val->is_oop(true), "Error"); 43 44 if (!JavaThread::satb_mark_queue_set().is_active()) return; 45 Thread* thr = Thread::current(); 46 if (thr->is_Java_thread()) { 47 JavaThread* jt = (JavaThread*)thr; 48 jt->satb_mark_queue().enqueue(pre_val); 49 } else { 50 MutexLockerEx x(Shared_SATB_Q_lock, Mutex::_no_safepoint_check_flag); 51 JavaThread::satb_mark_queue_set().shared_satb_queue()->enqueue(pre_val); 52 } 53 } 54 55 template <class T> void 56 G1SATBCardTableModRefBS::write_ref_array_pre_work(T* dst, int count) { 57 if (!JavaThread::satb_mark_queue_set().is_active()) return; 58 T* elem_ptr = dst; 59 for (int i = 0; i < count; i++, elem_ptr++) { 60 T heap_oop = oopDesc::load_heap_oop(elem_ptr); 61 if (!oopDesc::is_null(heap_oop)) { 62 enqueue(oopDesc::decode_heap_oop_not_null(heap_oop)); 63 } 64 } 65 } 66 67 bool G1SATBCardTableModRefBS::mark_card_deferred(size_t card_index) { 68 jbyte val = _byte_map[card_index]; 69 // It's already processed 70 if ((val & (clean_card_mask_val() | deferred_card_val())) == deferred_card_val()) { 71 return false; 72 } 73 74 if (val == g1_young_gen) { 75 // the card is for a young gen region. We don't need to keep track of all pointers into young 76 return false; 77 } 78 79 // Cached bit can be installed either on a clean card or on a claimed card. 80 jbyte new_val = val; 81 if (val == clean_card_val()) { 82 new_val = (jbyte)deferred_card_val(); 83 } else { 84 if (val & claimed_card_val()) { 85 new_val = val | (jbyte)deferred_card_val(); 86 } 87 } 88 if (new_val != val) { 89 Atomic::cmpxchg(new_val, &_byte_map[card_index], val); 90 } 91 return true; 92 } 93 94 void G1SATBCardTableModRefBS::g1_mark_as_young(const MemRegion& mr) { 95 jbyte *const first = byte_for(mr.start()); 96 jbyte *const last = byte_after(mr.last()); 97 98 memset(first, g1_young_gen, last - first); 99 } 100 101 #ifndef PRODUCT 102 void G1SATBCardTableModRefBS::verify_g1_young_region(MemRegion mr) { 103 verify_region(mr, g1_young_gen, true); 104 } 105 #endif 106 107 G1SATBCardTableLoggingModRefBS:: 108 G1SATBCardTableLoggingModRefBS(MemRegion whole_heap, 109 int max_covered_regions) : 110 G1SATBCardTableModRefBS(whole_heap, max_covered_regions), 111 _dcqs(JavaThread::dirty_card_queue_set()) 112 { 113 _kind = G1SATBCTLogging; 114 } 115 116 void 117 G1SATBCardTableLoggingModRefBS::write_ref_field_work(void* field, 118 oop new_val) { 119 volatile jbyte* byte = byte_for(field); 120 if (*byte == g1_young_gen) { 121 return; 122 } 123 OrderAccess::storeload(); 124 if (*byte != dirty_card) { 125 *byte = dirty_card; 126 Thread* thr = Thread::current(); 127 if (thr->is_Java_thread()) { 128 JavaThread* jt = (JavaThread*)thr; 129 jt->dirty_card_queue().enqueue(byte); 130 } else { 131 MutexLockerEx x(Shared_DirtyCardQ_lock, 132 Mutex::_no_safepoint_check_flag); 133 _dcqs.shared_dirty_card_queue()->enqueue(byte); 134 } 135 } 136 } 137 138 void 139 G1SATBCardTableLoggingModRefBS::write_ref_field_static(void* field, 140 oop new_val) { 141 uintptr_t field_uint = (uintptr_t)field; 142 uintptr_t new_val_uint = (uintptr_t)new_val; 143 uintptr_t comb = field_uint ^ new_val_uint; 144 comb = comb >> HeapRegion::LogOfHRGrainBytes; 145 if (comb == 0) return; 146 if (new_val == NULL) return; 147 // Otherwise, log it. 148 G1SATBCardTableLoggingModRefBS* g1_bs = 149 (G1SATBCardTableLoggingModRefBS*)Universe::heap()->barrier_set(); 150 g1_bs->write_ref_field_work(field, new_val); 151 } 152 153 void 154 G1SATBCardTableLoggingModRefBS::invalidate(MemRegion mr, bool whole_heap) { 155 volatile jbyte* byte = byte_for(mr.start()); 156 jbyte* last_byte = byte_for(mr.last()); 157 Thread* thr = Thread::current(); 158 if (whole_heap) { 159 while (byte <= last_byte) { 160 *byte = dirty_card; 161 byte++; 162 } 163 } else { 164 // Enqueue if necessary. 165 if (thr->is_Java_thread()) { 166 JavaThread* jt = (JavaThread*)thr; 167 for (; byte <= last_byte; byte++) { 168 if (*byte == g1_young_gen) { 169 continue; 170 } 171 OrderAccess::storeload(); 172 if (*byte != dirty_card) { 173 *byte = dirty_card; 174 jt->dirty_card_queue().enqueue(byte); 175 } 176 } 177 } else { 178 MutexLockerEx x(Shared_DirtyCardQ_lock, 179 Mutex::_no_safepoint_check_flag); 180 for (; byte <= last_byte; byte++) { 181 if (*byte == g1_young_gen) { 182 continue; 183 } 184 OrderAccess::storeload(); 185 if (*byte != dirty_card) { 186 *byte = dirty_card; 187 _dcqs.shared_dirty_card_queue()->enqueue(byte); 188 } 189 } 190 } 191 } 192 }