| /* |
| * Copyright (c) 2001, 2015, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "gc/g1/g1CollectedHeap.inline.hpp" |
| #include "gc/g1/g1SATBCardTableModRefBS.hpp" |
| #include "gc/g1/heapRegion.hpp" |
| #include "gc/g1/satbMarkQueue.hpp" |
| #include "gc/shared/memset_with_concurrent_readers.hpp" |
| #include "oops/oop.inline.hpp" |
| #include "runtime/atomic.inline.hpp" |
| #include "runtime/mutexLocker.hpp" |
| #include "runtime/orderAccess.inline.hpp" |
| #include "runtime/thread.inline.hpp" |
| |
| G1SATBCardTableModRefBS::G1SATBCardTableModRefBS( |
| MemRegion whole_heap, |
| const BarrierSet::FakeRtti& fake_rtti) : |
| CardTableModRefBS(whole_heap, fake_rtti.add_tag(BarrierSet::G1SATBCT)) |
| { } |
| |
| void G1SATBCardTableModRefBS::enqueue(oop pre_val) { |
| // Nulls should have been already filtered. |
| assert(pre_val->is_oop(true), "Error"); |
| |
| if (!JavaThread::satb_mark_queue_set().is_active()) return; |
| Thread* thr = Thread::current(); |
| if (thr->is_Java_thread()) { |
| JavaThread* jt = (JavaThread*)thr; |
| jt->satb_mark_queue().enqueue(pre_val); |
| } else { |
| MutexLockerEx x(Shared_SATB_Q_lock, Mutex::_no_safepoint_check_flag); |
| JavaThread::satb_mark_queue_set().shared_satb_queue()->enqueue(pre_val); |
| } |
| } |
| |
| template <class T> void |
| G1SATBCardTableModRefBS::write_ref_array_pre_work(T* dst, int count) { |
| if (!JavaThread::satb_mark_queue_set().is_active()) return; |
| T* elem_ptr = dst; |
| for (int i = 0; i < count; i++, elem_ptr++) { |
| T heap_oop = oopDesc::load_heap_oop(elem_ptr); |
| if (!oopDesc::is_null(heap_oop)) { |
| enqueue(oopDesc::decode_heap_oop_not_null(heap_oop)); |
| } |
| } |
| } |
| |
| void G1SATBCardTableModRefBS::write_ref_array_pre(oop* dst, int count, bool dest_uninitialized) { |
| if (!dest_uninitialized) { |
| write_ref_array_pre_work(dst, count); |
| } |
| } |
| void G1SATBCardTableModRefBS::write_ref_array_pre(narrowOop* dst, int count, bool dest_uninitialized) { |
| if (!dest_uninitialized) { |
| write_ref_array_pre_work(dst, count); |
| } |
| } |
| |
| bool G1SATBCardTableModRefBS::mark_card_deferred(size_t card_index) { |
| jbyte val = _byte_map[card_index]; |
| // It's already processed |
| if ((val & (clean_card_mask_val() | deferred_card_val())) == deferred_card_val()) { |
| return false; |
| } |
| |
| if (val == g1_young_gen) { |
| // the card is for a young gen region. We don't need to keep track of all pointers into young |
| return false; |
| } |
| |
| // Cached bit can be installed either on a clean card or on a claimed card. |
| jbyte new_val = val; |
| if (val == clean_card_val()) { |
| new_val = (jbyte)deferred_card_val(); |
| } else { |
| if (val & claimed_card_val()) { |
| new_val = val | (jbyte)deferred_card_val(); |
| } |
| } |
| if (new_val != val) { |
| Atomic::cmpxchg(new_val, &_byte_map[card_index], val); |
| } |
| return true; |
| } |
| |
| void G1SATBCardTableModRefBS::g1_mark_as_young(const MemRegion& mr) { |
| jbyte *const first = byte_for(mr.start()); |
| jbyte *const last = byte_after(mr.last()); |
| |
| memset_with_concurrent_readers(first, g1_young_gen, last - first); |
| } |
| |
| #ifndef PRODUCT |
| void G1SATBCardTableModRefBS::verify_g1_young_region(MemRegion mr) { |
| verify_region(mr, g1_young_gen, true); |
| } |
| #endif |
| |
| void G1SATBCardTableLoggingModRefBSChangedListener::on_commit(uint start_idx, size_t num_regions, bool zero_filled) { |
| // Default value for a clean card on the card table is -1. So we cannot take advantage of the zero_filled parameter. |
| MemRegion mr(G1CollectedHeap::heap()->bottom_addr_for_region(start_idx), num_regions * HeapRegion::GrainWords); |
| _card_table->clear(mr); |
| } |
| |
| G1SATBCardTableLoggingModRefBS:: |
| G1SATBCardTableLoggingModRefBS(MemRegion whole_heap) : |
| G1SATBCardTableModRefBS(whole_heap, BarrierSet::FakeRtti(G1SATBCTLogging)), |
| _dcqs(JavaThread::dirty_card_queue_set()), |
| _listener() |
| { |
| _listener.set_card_table(this); |
| } |
| |
| void G1SATBCardTableLoggingModRefBS::initialize(G1RegionToSpaceMapper* mapper) { |
| mapper->set_mapping_changed_listener(&_listener); |
| |
| _byte_map_size = mapper->reserved().byte_size(); |
| |
| _guard_index = cards_required(_whole_heap.word_size()) - 1; |
| _last_valid_index = _guard_index - 1; |
| |
| HeapWord* low_bound = _whole_heap.start(); |
| HeapWord* high_bound = _whole_heap.end(); |
| |
| _cur_covered_regions = 1; |
| _covered[0] = _whole_heap; |
| |
| _byte_map = (jbyte*) mapper->reserved().start(); |
| byte_map_base = _byte_map - (uintptr_t(low_bound) >> card_shift); |
| assert(byte_for(low_bound) == &_byte_map[0], "Checking start of map"); |
| assert(byte_for(high_bound-1) <= &_byte_map[_last_valid_index], "Checking end of map"); |
| |
| if (TraceCardTableModRefBS) { |
| gclog_or_tty->print_cr("G1SATBCardTableModRefBS::G1SATBCardTableModRefBS: "); |
| gclog_or_tty->print_cr(" " |
| " &_byte_map[0]: " INTPTR_FORMAT |
| " &_byte_map[_last_valid_index]: " INTPTR_FORMAT, |
| p2i(&_byte_map[0]), |
| p2i(&_byte_map[_last_valid_index])); |
| gclog_or_tty->print_cr(" " |
| " byte_map_base: " INTPTR_FORMAT, |
| p2i(byte_map_base)); |
| } |
| } |
| |
| void |
| G1SATBCardTableLoggingModRefBS::write_ref_field_work(void* field, |
| oop new_val, |
| bool release) { |
| volatile jbyte* byte = byte_for(field); |
| if (*byte == g1_young_gen) { |
| return; |
| } |
| OrderAccess::storeload(); |
| if (*byte != dirty_card) { |
| *byte = dirty_card; |
| Thread* thr = Thread::current(); |
| if (thr->is_Java_thread()) { |
| JavaThread* jt = (JavaThread*)thr; |
| jt->dirty_card_queue().enqueue(byte); |
| } else { |
| MutexLockerEx x(Shared_DirtyCardQ_lock, |
| Mutex::_no_safepoint_check_flag); |
| _dcqs.shared_dirty_card_queue()->enqueue(byte); |
| } |
| } |
| } |
| |
| void |
| G1SATBCardTableLoggingModRefBS::invalidate(MemRegion mr, bool whole_heap) { |
| volatile jbyte* byte = byte_for(mr.start()); |
| jbyte* last_byte = byte_for(mr.last()); |
| Thread* thr = Thread::current(); |
| if (whole_heap) { |
| while (byte <= last_byte) { |
| *byte = dirty_card; |
| byte++; |
| } |
| } else { |
| // skip all consecutive young cards |
| for (; byte <= last_byte && *byte == g1_young_gen; byte++); |
| |
| if (byte <= last_byte) { |
| OrderAccess::storeload(); |
| // Enqueue if necessary. |
| if (thr->is_Java_thread()) { |
| JavaThread* jt = (JavaThread*)thr; |
| for (; byte <= last_byte; byte++) { |
| if (*byte == g1_young_gen) { |
| continue; |
| } |
| if (*byte != dirty_card) { |
| *byte = dirty_card; |
| jt->dirty_card_queue().enqueue(byte); |
| } |
| } |
| } else { |
| MutexLockerEx x(Shared_DirtyCardQ_lock, |
| Mutex::_no_safepoint_check_flag); |
| for (; byte <= last_byte; byte++) { |
| if (*byte == g1_young_gen) { |
| continue; |
| } |
| if (*byte != dirty_card) { |
| *byte = dirty_card; |
| _dcqs.shared_dirty_card_queue()->enqueue(byte); |
| } |
| } |
| } |
| } |
| } |
| } |
| |
| void G1SATBCardTableModRefBS::write_ref_nmethod_post(oop* dst, nmethod* nm) { |
| oop obj = oopDesc::load_heap_oop(dst); |
| if (obj != NULL) { |
| G1CollectedHeap* g1h = G1CollectedHeap::heap(); |
| HeapRegion* hr = g1h->heap_region_containing(obj); |
| hr->add_strong_code_root(nm); |
| } |
| } |
| |
| class G1EnsureLastRefToRegion : public OopClosure { |
| G1CollectedHeap* _g1h; |
| HeapRegion* _hr; |
| oop* _dst; |
| |
| bool _value; |
| public: |
| G1EnsureLastRefToRegion(G1CollectedHeap* g1h, HeapRegion* hr, oop* dst) : |
| _g1h(g1h), _hr(hr), _dst(dst), _value(true) {} |
| |
| void do_oop(oop* p) { |
| if (_value && p != _dst) { |
| oop obj = oopDesc::load_heap_oop(p); |
| if (obj != NULL) { |
| HeapRegion* hr = _g1h->heap_region_containing(obj); |
| if (hr == _hr) { |
| // Another reference to the same region. |
| _value = false; |
| } |
| } |
| } |
| } |
| void do_oop(narrowOop* p) { ShouldNotReachHere(); } |
| bool value() const { return _value; } |
| }; |
| |
| void G1SATBCardTableModRefBS::write_ref_nmethod_pre(oop* dst, nmethod* nm) { |
| oop obj = oopDesc::load_heap_oop(dst); |
| if (obj != NULL) { |
| G1CollectedHeap* g1h = G1CollectedHeap::heap(); |
| HeapRegion* hr = g1h->heap_region_containing(obj); |
| G1EnsureLastRefToRegion ensure_last_ref(g1h, hr, dst); |
| nm->oops_do(&ensure_last_ref); |
| if (ensure_last_ref.value()) { |
| // Last reference to this region, remove the nmethod from the rset. |
| hr->remove_strong_code_root(nm); |
| } |
| } |
| } |