| /* |
| * Copyright (c) 2014, 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_SHARED_CARDGENERATION_HPP |
| #define SHARE_VM_GC_SHARED_CARDGENERATION_HPP |
| |
| // Class CardGeneration is a generation that is covered by a card table, |
| // and uses a card-size block-offset array to implement block_start. |
| |
| #include "gc/shared/generation.hpp" |
| |
| class BlockOffsetSharedArray; |
| class CompactibleSpace; |
| |
| class CardGeneration: public Generation { |
| friend class VMStructs; |
| protected: |
| // This is shared with other generations. |
| GenRemSet* _rs; |
| // This is local to this generation. |
| BlockOffsetSharedArray* _bts; |
| |
| // Current shrinking effect: this damps shrinking when the heap gets empty. |
| size_t _shrink_factor; |
| |
| size_t _min_heap_delta_bytes; // Minimum amount to expand. |
| |
| // Some statistics from before gc started. |
| // These are gathered in the gc_prologue (and should_collect) |
| // to control growing/shrinking policy in spite of promotions. |
| size_t _capacity_at_prologue; |
| size_t _used_at_prologue; |
| |
| CardGeneration(ReservedSpace rs, size_t initial_byte_size, GenRemSet* remset); |
| |
| virtual void assert_correct_size_change_locking() = 0; |
| |
| virtual CompactibleSpace* space() const = 0; |
| |
| public: |
| |
| // Attempt to expand the generation by "bytes". Expand by at a |
| // minimum "expand_bytes". Return true if some amount (not |
| // necessarily the full "bytes") was done. |
| virtual bool expand(size_t bytes, size_t expand_bytes); |
| |
| // Shrink generation with specified size |
| virtual void shrink(size_t bytes); |
| |
| virtual void compute_new_size(); |
| |
| virtual void clear_remembered_set(); |
| |
| virtual void invalidate_remembered_set(); |
| |
| virtual void prepare_for_verify(); |
| |
| // Grow generation with specified size (returns false if unable to grow) |
| bool grow_by(size_t bytes); |
| // Grow generation to reserved size. |
| bool grow_to_reserved(); |
| |
| size_t capacity() const; |
| size_t used() const; |
| size_t free() const; |
| MemRegion used_region() const; |
| |
| void space_iterate(SpaceClosure* blk, bool usedOnly = false); |
| |
| void younger_refs_iterate(OopsInGenClosure* blk, uint n_threads); |
| |
| bool is_in(const void* p) const; |
| |
| CompactibleSpace* first_compaction_space() const; |
| }; |
| |
| #endif // SHARE_VM_GC_SHARED_CARDGENERATION_HPP |