| /* |
| * Copyright (c) 2013, 2014, 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_implementation/g1/g1CardCounts.hpp" |
| #include "gc_implementation/g1/g1CollectedHeap.inline.hpp" |
| #include "gc_implementation/g1/g1CollectorPolicy.hpp" |
| #include "gc_implementation/g1/g1GCPhaseTimes.hpp" |
| #include "memory/cardTableModRefBS.hpp" |
| #include "services/memTracker.hpp" |
| #include "utilities/copy.hpp" |
| |
| PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC |
| |
| void G1CardCountsMappingChangedListener::on_commit(uint start_idx, size_t num_regions, bool zero_filled) { |
| if (zero_filled) { |
| return; |
| } |
| MemRegion mr(G1CollectedHeap::heap()->bottom_addr_for_region(start_idx), num_regions * HeapRegion::GrainWords); |
| _counts->clear_range(mr); |
| } |
| |
| void G1CardCounts::clear_range(size_t from_card_num, size_t to_card_num) { |
| if (has_count_table()) { |
| assert(from_card_num < to_card_num, |
| err_msg("Wrong order? from: " SIZE_FORMAT ", to: "SIZE_FORMAT, |
| from_card_num, to_card_num)); |
| Copy::fill_to_bytes(&_card_counts[from_card_num], (to_card_num - from_card_num)); |
| } |
| } |
| |
| G1CardCounts::G1CardCounts(G1CollectedHeap *g1h): |
| _listener(), _g1h(g1h), _card_counts(NULL), _reserved_max_card_num(0) { |
| _listener.set_cardcounts(this); |
| } |
| |
| void G1CardCounts::initialize(G1RegionToSpaceMapper* mapper) { |
| assert(_g1h->max_capacity() > 0, "initialization order"); |
| assert(_g1h->capacity() == 0, "initialization order"); |
| |
| if (G1ConcRSHotCardLimit > 0) { |
| // The max value we can store in the counts table is |
| // max_jubyte. Guarantee the value of the hot |
| // threshold limit is no more than this. |
| guarantee(G1ConcRSHotCardLimit <= max_jubyte, "sanity"); |
| |
| _ct_bs = _g1h->g1_barrier_set(); |
| _ct_bot = _ct_bs->byte_for_const(_g1h->reserved_region().start()); |
| |
| _card_counts = (jubyte*) mapper->reserved().start(); |
| _reserved_max_card_num = mapper->reserved().byte_size(); |
| mapper->set_mapping_changed_listener(&_listener); |
| } |
| } |
| |
| uint G1CardCounts::add_card_count(jbyte* card_ptr) { |
| // Returns the number of times the card has been refined. |
| // If we failed to reserve/commit the counts table, return 0. |
| // If card_ptr is beyond the committed end of the counts table, |
| // return 0. |
| // Otherwise return the actual count. |
| // Unless G1ConcRSHotCardLimit has been set appropriately, |
| // returning 0 will result in the card being considered |
| // cold and will be refined immediately. |
| uint count = 0; |
| if (has_count_table()) { |
| size_t card_num = ptr_2_card_num(card_ptr); |
| assert(card_num < _reserved_max_card_num, |
| err_msg("Card "SIZE_FORMAT" outside of card counts table (max size "SIZE_FORMAT")", |
| card_num, _reserved_max_card_num)); |
| count = (uint) _card_counts[card_num]; |
| if (count < G1ConcRSHotCardLimit) { |
| _card_counts[card_num] = |
| (jubyte)(MIN2((uintx)(_card_counts[card_num] + 1), G1ConcRSHotCardLimit)); |
| } |
| } |
| return count; |
| } |
| |
| bool G1CardCounts::is_hot(uint count) { |
| return (count >= G1ConcRSHotCardLimit); |
| } |
| |
| void G1CardCounts::clear_region(HeapRegion* hr) { |
| MemRegion mr(hr->bottom(), hr->end()); |
| clear_range(mr); |
| } |
| |
| void G1CardCounts::clear_range(MemRegion mr) { |
| if (has_count_table()) { |
| const jbyte* from_card_ptr = _ct_bs->byte_for_const(mr.start()); |
| // We use the last address in the range as the range could represent the |
| // last region in the heap. In which case trying to find the card will be an |
| // OOB access to the card table. |
| const jbyte* last_card_ptr = _ct_bs->byte_for_const(mr.last()); |
| |
| #ifdef ASSERT |
| HeapWord* start_addr = _ct_bs->addr_for(from_card_ptr); |
| assert(start_addr == mr.start(), "MemRegion start must be aligned to a card."); |
| HeapWord* last_addr = _ct_bs->addr_for(last_card_ptr); |
| assert((last_addr + CardTableModRefBS::card_size_in_words) == mr.end(), "MemRegion end must be aligned to a card."); |
| #endif // ASSERT |
| |
| // Clear the counts for the (exclusive) card range. |
| size_t from_card_num = ptr_2_card_num(from_card_ptr); |
| size_t to_card_num = ptr_2_card_num(last_card_ptr) + 1; |
| clear_range(from_card_num, to_card_num); |
| } |
| } |
| |
| class G1CardCountsClearClosure : public HeapRegionClosure { |
| private: |
| G1CardCounts* _card_counts; |
| public: |
| G1CardCountsClearClosure(G1CardCounts* card_counts) : |
| HeapRegionClosure(), _card_counts(card_counts) { } |
| |
| |
| virtual bool doHeapRegion(HeapRegion* r) { |
| _card_counts->clear_region(r); |
| return false; |
| } |
| }; |
| |
| void G1CardCounts::clear_all() { |
| assert(SafepointSynchronize::is_at_safepoint(), "don't call this otherwise"); |
| G1CardCountsClearClosure cl(this); |
| _g1h->heap_region_iterate(&cl); |
| } |