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/g1/g1BarrierSet.inline.hpp" 27 #include "gc/g1/g1BarrierSetAssembler.hpp" 28 #include "gc/g1/g1CardTable.inline.hpp" 29 #include "gc/g1/g1CollectedHeap.inline.hpp" 30 #include "gc/g1/heapRegion.hpp" 31 #include "gc/g1/satbMarkQueue.hpp" 32 #include "logging/log.hpp" 33 #include "oops/access.inline.hpp" 34 #include "oops/compressedOops.inline.hpp" 35 #include "oops/oop.inline.hpp" 36 #include "runtime/mutexLocker.hpp" 37 #include "runtime/thread.inline.hpp" 38 #include "utilities/macros.hpp" 39 40 G1BarrierSet::G1BarrierSet(G1CardTable* card_table) : 41 CardTableBarrierSet(make_barrier_set_assembler<G1BarrierSetAssembler>(), 42 card_table, 43 BarrierSet::FakeRtti(BarrierSet::G1BarrierSet)), 44 _dcqs(JavaThread::dirty_card_queue_set()) 45 { } 46 47 void G1BarrierSet::enqueue(oop pre_val) { 48 // Nulls should have been already filtered. 49 assert(oopDesc::is_oop(pre_val, true), "Error"); 50 51 if (!JavaThread::satb_mark_queue_set().is_active()) return; 52 Thread* thr = Thread::current(); 53 if (thr->is_Java_thread()) { 54 JavaThread* jt = (JavaThread*)thr; 55 jt->satb_mark_queue().enqueue(pre_val); 56 } else { 57 MutexLockerEx x(Shared_SATB_Q_lock, Mutex::_no_safepoint_check_flag); 58 JavaThread::satb_mark_queue_set().shared_satb_queue()->enqueue(pre_val); 59 } 60 } 61 62 void G1BarrierSet::write_ref_array_pre_oop_entry(oop* dst, size_t length) { 63 G1BarrierSet *bs = barrier_set_cast<G1BarrierSet>(BarrierSet::barrier_set()); 64 bs->write_ref_array_pre(dst, length, false); 65 } 66 67 void G1BarrierSet::write_ref_array_pre_narrow_oop_entry(narrowOop* dst, size_t length) { 68 G1BarrierSet *bs = barrier_set_cast<G1BarrierSet>(BarrierSet::barrier_set()); 69 bs->write_ref_array_pre(dst, length, false); 70 } 71 72 void G1BarrierSet::write_ref_array_post_entry(HeapWord* dst, size_t length) { 73 G1BarrierSet *bs = barrier_set_cast<G1BarrierSet>(BarrierSet::barrier_set()); 74 bs->G1BarrierSet::write_ref_array(dst, length); 75 } 76 77 template <class T> void 78 G1BarrierSet::write_ref_array_pre_work(T* dst, size_t count) { 79 if (!JavaThread::satb_mark_queue_set().is_active()) return; 80 T* elem_ptr = dst; 81 for (size_t i = 0; i < count; i++, elem_ptr++) { 82 T heap_oop = RawAccess<>::oop_load(elem_ptr); 83 if (!CompressedOops::is_null(heap_oop)) { 84 enqueue(CompressedOops::decode_not_null(heap_oop)); 85 } 86 } 87 } 88 89 void G1BarrierSet::write_ref_array_pre(oop* dst, size_t count, bool dest_uninitialized) { 90 if (!dest_uninitialized) { 91 write_ref_array_pre_work(dst, count); 92 } 93 } 94 95 void G1BarrierSet::write_ref_array_pre(narrowOop* dst, size_t count, bool dest_uninitialized) { 96 if (!dest_uninitialized) { 97 write_ref_array_pre_work(dst, count); 98 } 99 } 100 101 void G1BarrierSet::write_ref_field_post_slow(volatile jbyte* byte) { 102 // In the slow path, we know a card is not young 103 assert(*byte != G1CardTable::g1_young_card_val(), "slow path invoked without filtering"); 104 OrderAccess::storeload(); 105 if (*byte != G1CardTable::dirty_card_val()) { 106 *byte = G1CardTable::dirty_card_val(); 107 Thread* thr = Thread::current(); 108 if (thr->is_Java_thread()) { 109 JavaThread* jt = (JavaThread*)thr; 110 jt->dirty_card_queue().enqueue(byte); 111 } else { 112 MutexLockerEx x(Shared_DirtyCardQ_lock, 113 Mutex::_no_safepoint_check_flag); 114 _dcqs.shared_dirty_card_queue()->enqueue(byte); 115 } 116 } 117 } 118 119 void G1BarrierSet::invalidate(MemRegion mr) { 120 if (mr.is_empty()) { 121 return; 122 } 123 volatile jbyte* byte = _card_table->byte_for(mr.start()); 124 jbyte* last_byte = _card_table->byte_for(mr.last()); 125 Thread* thr = Thread::current(); 126 // skip all consecutive young cards 127 for (; byte <= last_byte && *byte == G1CardTable::g1_young_card_val(); byte++); 128 129 if (byte <= last_byte) { 130 OrderAccess::storeload(); 131 // Enqueue if necessary. 132 if (thr->is_Java_thread()) { 133 JavaThread* jt = (JavaThread*)thr; 134 for (; byte <= last_byte; byte++) { 135 if (*byte == G1CardTable::g1_young_card_val()) { 136 continue; 137 } 138 if (*byte != G1CardTable::dirty_card_val()) { 139 *byte = G1CardTable::dirty_card_val(); 140 jt->dirty_card_queue().enqueue(byte); 141 } 142 } 143 } else { 144 MutexLockerEx x(Shared_DirtyCardQ_lock, 145 Mutex::_no_safepoint_check_flag); 146 for (; byte <= last_byte; byte++) { 147 if (*byte == G1CardTable::g1_young_card_val()) { 148 continue; 149 } 150 if (*byte != G1CardTable::dirty_card_val()) { 151 *byte = G1CardTable::dirty_card_val(); 152 _dcqs.shared_dirty_card_queue()->enqueue(byte); 153 } 154 } 155 } 156 } 157 } 158 159 void G1BarrierSet::on_thread_attach(JavaThread* thread) { 160 // This method initializes the SATB and dirty card queues before a 161 // JavaThread is added to the Java thread list. Right now, we don't 162 // have to do anything to the dirty card queue (it should have been 163 // activated when the thread was created), but we have to activate 164 // the SATB queue if the thread is created while a marking cycle is 165 // in progress. The activation / de-activation of the SATB queues at 166 // the beginning / end of a marking cycle is done during safepoints 167 // so we have to make sure this method is called outside one to be 168 // able to safely read the active field of the SATB queue set. Right 169 // now, it is called just before the thread is added to the Java 170 // thread list in the Threads::add() method. That method is holding 171 // the Threads_lock which ensures we are outside a safepoint. We 172 // cannot do the obvious and set the active field of the SATB queue 173 // when the thread is created given that, in some cases, safepoints 174 // might happen between the JavaThread constructor being called and the 175 // thread being added to the Java thread list (an example of this is 176 // when the structure for the DestroyJavaVM thread is created). 177 assert(!SafepointSynchronize::is_at_safepoint(), "We should not be at a safepoint"); 178 assert(!thread->satb_mark_queue().is_active(), "SATB queue should not be active"); 179 assert(thread->satb_mark_queue().is_empty(), "SATB queue should be empty"); 180 assert(thread->dirty_card_queue().is_active(), "Dirty card queue should be active"); 181 182 // If we are creating the thread during a marking cycle, we should 183 // set the active field of the SATB queue to true. 184 if (thread->satb_mark_queue_set().is_active()) { 185 thread->satb_mark_queue().set_active(true); 186 } 187 } 188 189 void G1BarrierSet::on_thread_detach(JavaThread* thread) { 190 // Flush any deferred card marks, SATB buffers and dirty card queue buffers 191 CardTableBarrierSet::on_thread_detach(thread); 192 thread->satb_mark_queue().flush(); 193 thread->dirty_card_queue().flush(); 194 } | 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/g1/g1BarrierSet.inline.hpp" 27 #include "gc/g1/g1BarrierSetAssembler.hpp" 28 #include "gc/g1/g1CardTable.inline.hpp" 29 #include "gc/g1/g1CollectedHeap.inline.hpp" 30 #include "gc/g1/heapRegion.hpp" 31 #include "gc/g1/satbMarkQueue.hpp" 32 #include "logging/log.hpp" 33 #include "oops/access.inline.hpp" 34 #include "oops/compressedOops.inline.hpp" 35 #include "oops/oop.inline.hpp" 36 #include "runtime/mutexLocker.hpp" 37 #include "runtime/thread.inline.hpp" 38 #include "utilities/macros.hpp" 39 40 SATBMarkQueueSet G1BarrierSet::_satb_mark_queue_set; 41 DirtyCardQueueSet G1BarrierSet::_dirty_card_queue_set; 42 43 G1BarrierSet::G1BarrierSet(G1CardTable* card_table) : 44 CardTableBarrierSet(make_barrier_set_assembler<G1BarrierSetAssembler>(), 45 card_table, 46 BarrierSet::FakeRtti(BarrierSet::G1BarrierSet)) {} 47 48 void G1BarrierSet::enqueue(oop pre_val) { 49 // Nulls should have been already filtered. 50 assert(oopDesc::is_oop(pre_val, true), "Error"); 51 52 if (!_satb_mark_queue_set.is_active()) return; 53 Thread* thr = Thread::current(); 54 if (thr->is_Java_thread()) { 55 JavaThread* jt = (JavaThread*)thr; 56 jt->satb_mark_queue().enqueue(pre_val); 57 } else { 58 MutexLockerEx x(Shared_SATB_Q_lock, Mutex::_no_safepoint_check_flag); 59 _satb_mark_queue_set.shared_satb_queue()->enqueue(pre_val); 60 } 61 } 62 63 void G1BarrierSet::write_ref_array_pre_oop_entry(oop* dst, size_t length) { 64 G1BarrierSet *bs = barrier_set_cast<G1BarrierSet>(BarrierSet::barrier_set()); 65 bs->write_ref_array_pre(dst, length, false); 66 } 67 68 void G1BarrierSet::write_ref_array_pre_narrow_oop_entry(narrowOop* dst, size_t length) { 69 G1BarrierSet *bs = barrier_set_cast<G1BarrierSet>(BarrierSet::barrier_set()); 70 bs->write_ref_array_pre(dst, length, false); 71 } 72 73 void G1BarrierSet::write_ref_array_post_entry(HeapWord* dst, size_t length) { 74 G1BarrierSet *bs = barrier_set_cast<G1BarrierSet>(BarrierSet::barrier_set()); 75 bs->G1BarrierSet::write_ref_array(dst, length); 76 } 77 78 template <class T> void 79 G1BarrierSet::write_ref_array_pre_work(T* dst, size_t count) { 80 if (!_satb_mark_queue_set.is_active()) return; 81 T* elem_ptr = dst; 82 for (size_t i = 0; i < count; i++, elem_ptr++) { 83 T heap_oop = RawAccess<>::oop_load(elem_ptr); 84 if (!CompressedOops::is_null(heap_oop)) { 85 enqueue(CompressedOops::decode_not_null(heap_oop)); 86 } 87 } 88 } 89 90 void G1BarrierSet::write_ref_array_pre(oop* dst, size_t count, bool dest_uninitialized) { 91 if (!dest_uninitialized) { 92 write_ref_array_pre_work(dst, count); 93 } 94 } 95 96 void G1BarrierSet::write_ref_array_pre(narrowOop* dst, size_t count, bool dest_uninitialized) { 97 if (!dest_uninitialized) { 98 write_ref_array_pre_work(dst, count); 99 } 100 } 101 102 void G1BarrierSet::write_ref_field_post_slow(volatile jbyte* byte) { 103 // In the slow path, we know a card is not young 104 assert(*byte != G1CardTable::g1_young_card_val(), "slow path invoked without filtering"); 105 OrderAccess::storeload(); 106 if (*byte != G1CardTable::dirty_card_val()) { 107 *byte = G1CardTable::dirty_card_val(); 108 Thread* thr = Thread::current(); 109 if (thr->is_Java_thread()) { 110 JavaThread* jt = (JavaThread*)thr; 111 jt->dirty_card_queue().enqueue(byte); 112 } else { 113 MutexLockerEx x(Shared_DirtyCardQ_lock, 114 Mutex::_no_safepoint_check_flag); 115 _dirty_card_queue_set.shared_dirty_card_queue()->enqueue(byte); 116 } 117 } 118 } 119 120 void G1BarrierSet::invalidate(MemRegion mr) { 121 if (mr.is_empty()) { 122 return; 123 } 124 volatile jbyte* byte = _card_table->byte_for(mr.start()); 125 jbyte* last_byte = _card_table->byte_for(mr.last()); 126 Thread* thr = Thread::current(); 127 // skip all consecutive young cards 128 for (; byte <= last_byte && *byte == G1CardTable::g1_young_card_val(); byte++); 129 130 if (byte <= last_byte) { 131 OrderAccess::storeload(); 132 // Enqueue if necessary. 133 if (thr->is_Java_thread()) { 134 JavaThread* jt = (JavaThread*)thr; 135 for (; byte <= last_byte; byte++) { 136 if (*byte == G1CardTable::g1_young_card_val()) { 137 continue; 138 } 139 if (*byte != G1CardTable::dirty_card_val()) { 140 *byte = G1CardTable::dirty_card_val(); 141 jt->dirty_card_queue().enqueue(byte); 142 } 143 } 144 } else { 145 MutexLockerEx x(Shared_DirtyCardQ_lock, 146 Mutex::_no_safepoint_check_flag); 147 for (; byte <= last_byte; byte++) { 148 if (*byte == G1CardTable::g1_young_card_val()) { 149 continue; 150 } 151 if (*byte != G1CardTable::dirty_card_val()) { 152 *byte = G1CardTable::dirty_card_val(); 153 _dirty_card_queue_set.shared_dirty_card_queue()->enqueue(byte); 154 } 155 } 156 } 157 } 158 } 159 160 void G1BarrierSet::on_thread_attach(JavaThread* thread) { 161 // This method initializes the SATB and dirty card queues before a 162 // JavaThread is added to the Java thread list. Right now, we don't 163 // have to do anything to the dirty card queue (it should have been 164 // activated when the thread was created), but we have to activate 165 // the SATB queue if the thread is created while a marking cycle is 166 // in progress. The activation / de-activation of the SATB queues at 167 // the beginning / end of a marking cycle is done during safepoints 168 // so we have to make sure this method is called outside one to be 169 // able to safely read the active field of the SATB queue set. Right 170 // now, it is called just before the thread is added to the Java 171 // thread list in the Threads::add() method. That method is holding 172 // the Threads_lock which ensures we are outside a safepoint. We 173 // cannot do the obvious and set the active field of the SATB queue 174 // when the thread is created given that, in some cases, safepoints 175 // might happen between the JavaThread constructor being called and the 176 // thread being added to the Java thread list (an example of this is 177 // when the structure for the DestroyJavaVM thread is created). 178 assert(!SafepointSynchronize::is_at_safepoint(), "We should not be at a safepoint"); 179 assert(!thread->satb_mark_queue().is_active(), "SATB queue should not be active"); 180 assert(thread->satb_mark_queue().is_empty(), "SATB queue should be empty"); 181 assert(thread->dirty_card_queue().is_active(), "Dirty card queue should be active"); 182 183 // If we are creating the thread during a marking cycle, we should 184 // set the active field of the SATB queue to true. 185 if (_satb_mark_queue_set.is_active()) { 186 thread->satb_mark_queue().set_active(true); 187 } 188 } 189 190 void G1BarrierSet::on_thread_detach(JavaThread* thread) { 191 // Flush any deferred card marks, SATB buffers and dirty card queue buffers 192 CardTableBarrierSet::on_thread_detach(thread); 193 thread->satb_mark_queue().flush(); 194 thread->dirty_card_queue().flush(); 195 } |