| /* |
| * Copyright (c) 2003, 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_PARALLEL_ADJOININGGENERATIONS_HPP |
| #define SHARE_VM_GC_PARALLEL_ADJOININGGENERATIONS_HPP |
| |
| #include "gc/parallel/adjoiningVirtualSpaces.hpp" |
| #include "gc/parallel/asPSOldGen.hpp" |
| #include "gc/parallel/asPSYoungGen.hpp" |
| #include "gc/parallel/generationSizer.hpp" |
| |
| |
| // Contains two generations that both use an AdjoiningVirtualSpaces. |
| // The two generations are adjacent in the reserved space for the |
| // heap. Each generation has a virtual space and shrinking and |
| // expanding of the generations can still be down with that |
| // virtual space as was previously done. If expanding of reserved |
| // size of a generation is required, the adjacent generation |
| // must be shrunk. Adjusting the boundary between the generations |
| // is called for in this class. |
| |
| class AdjoiningGenerations : public CHeapObj<mtGC> { |
| friend class VMStructs; |
| private: |
| // The young generation and old generation, respectively |
| PSYoungGen* _young_gen; |
| PSOldGen* _old_gen; |
| |
| // The spaces used by the two generations. |
| AdjoiningVirtualSpaces _virtual_spaces; |
| |
| // Move boundary up to expand old gen. Checks are made to |
| // determine if the move can be done with specified limits. |
| void request_old_gen_expansion(size_t desired_change_in_bytes); |
| // Move boundary down to expand young gen. |
| bool request_young_gen_expansion(size_t desired_change_in_bytes); |
| |
| public: |
| AdjoiningGenerations(ReservedSpace rs, GenerationSizer* policy, size_t alignment); |
| |
| // Accessors |
| PSYoungGen* young_gen() { return _young_gen; } |
| PSOldGen* old_gen() { return _old_gen; } |
| |
| AdjoiningVirtualSpaces* virtual_spaces() { return &_virtual_spaces; } |
| |
| // Additional space is needed in the old generation. Check |
| // the available space and attempt to move the boundary if more space |
| // is needed. The growth is not guaranteed to occur. |
| void adjust_boundary_for_old_gen_needs(size_t desired_change_in_bytes); |
| // Similarly for a growth of the young generation. |
| void adjust_boundary_for_young_gen_needs(size_t eden_size, size_t survivor_size); |
| |
| // Return the total byte size of the reserved space |
| // for the adjoining generations. |
| size_t reserved_byte_size(); |
| }; |
| |
| #endif // SHARE_VM_GC_PARALLEL_ADJOININGGENERATIONS_HPP |