| /* |
| * Copyright (c) 2013, 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. |
| * |
| */ |
| |
| #ifndef SHARE_VM_GC_G1_G1CARDCOUNTS_HPP |
| #define SHARE_VM_GC_G1_G1CARDCOUNTS_HPP |
| |
| #include "gc/g1/g1RegionToSpaceMapper.hpp" |
| #include "memory/allocation.hpp" |
| #include "memory/virtualspace.hpp" |
| #include "utilities/globalDefinitions.hpp" |
| |
| class CardTableModRefBS; |
| class G1CardCounts; |
| class G1CollectedHeap; |
| class G1RegionToSpaceMapper; |
| class HeapRegion; |
| |
| class G1CardCountsMappingChangedListener : public G1MappingChangedListener { |
| private: |
| G1CardCounts* _counts; |
| public: |
| void set_cardcounts(G1CardCounts* counts) { _counts = counts; } |
| |
| virtual void on_commit(uint start_idx, size_t num_regions, bool zero_filled); |
| }; |
| |
| // Table to track the number of times a card has been refined. Once |
| // a card has been refined a certain number of times, it is |
| // considered 'hot' and its refinement is delayed by inserting the |
| // card into the hot card cache. The card will then be refined when |
| // it is evicted from the hot card cache, or when the hot card cache |
| // is 'drained' during the next evacuation pause. |
| |
| class G1CardCounts: public CHeapObj<mtGC> { |
| G1CardCountsMappingChangedListener _listener; |
| |
| G1CollectedHeap* _g1h; |
| |
| // The table of counts |
| jubyte* _card_counts; |
| |
| // Max capacity of the reserved space for the counts table |
| size_t _reserved_max_card_num; |
| |
| // CardTable bottom. |
| const jbyte* _ct_bot; |
| |
| // Barrier set |
| CardTableModRefBS* _ct_bs; |
| |
| // Returns true if the card counts table has been reserved. |
| bool has_reserved_count_table() { return _card_counts != NULL; } |
| |
| // Returns true if the card counts table has been reserved and committed. |
| bool has_count_table() { |
| return has_reserved_count_table(); |
| } |
| |
| size_t ptr_2_card_num(const jbyte* card_ptr) { |
| assert(card_ptr >= _ct_bot, |
| "Invalid card pointer: " |
| "card_ptr: " PTR_FORMAT ", " |
| "_ct_bot: " PTR_FORMAT, |
| p2i(card_ptr), p2i(_ct_bot)); |
| size_t card_num = pointer_delta(card_ptr, _ct_bot, sizeof(jbyte)); |
| assert(card_num < _reserved_max_card_num, |
| "card pointer out of range: " PTR_FORMAT, p2i(card_ptr)); |
| return card_num; |
| } |
| |
| jbyte* card_num_2_ptr(size_t card_num) { |
| assert(card_num < _reserved_max_card_num, |
| "card num out of range: " SIZE_FORMAT, card_num); |
| return (jbyte*) (_ct_bot + card_num); |
| } |
| |
| // Clear the counts table for the given (exclusive) index range. |
| void clear_range(size_t from_card_num, size_t to_card_num); |
| |
| public: |
| G1CardCounts(G1CollectedHeap* g1h); |
| |
| // Return the number of slots needed for a card counts table |
| // that covers mem_region_words words. |
| static size_t compute_size(size_t mem_region_size_in_words); |
| |
| // Returns how many bytes of the heap a single byte of the card counts table |
| // corresponds to. |
| static size_t heap_map_factor(); |
| |
| void initialize(G1RegionToSpaceMapper* mapper); |
| |
| // Increments the refinement count for the given card. |
| // Returns the pre-increment count value. |
| uint add_card_count(jbyte* card_ptr); |
| |
| // Returns true if the given count is high enough to be considered |
| // 'hot'; false otherwise. |
| bool is_hot(uint count); |
| |
| // Clears the card counts for the cards spanned by the region |
| void clear_region(HeapRegion* hr); |
| |
| // Clears the card counts for the cards spanned by the MemRegion |
| void clear_range(MemRegion mr); |
| |
| // Clear the entire card counts table during GC. |
| void clear_all(); |
| }; |
| |
| #endif // SHARE_VM_GC_G1_G1CARDCOUNTS_HPP |