src/share/vm/gc_implementation/parallelScavenge/adjoiningVirtualSpaces.hpp

Fri, 16 Mar 2012 16:14:04 +0100

author
nloodin
date
Fri, 16 Mar 2012 16:14:04 +0100
changeset 3665
8a729074feae
parent 2314
f95d63e2154a
child 6876
710a3c8b516e
permissions
-rw-r--r--

7154517: Build error in hotspot-gc without precompiled headers
Reviewed-by: jcoomes, brutisso

duke@435 1 /*
stefank@2314 2 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
duke@435 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435 4 *
duke@435 5 * This code is free software; you can redistribute it and/or modify it
duke@435 6 * under the terms of the GNU General Public License version 2 only, as
duke@435 7 * published by the Free Software Foundation.
duke@435 8 *
duke@435 9 * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@435 12 * version 2 for more details (a copy is included in the LICENSE file that
duke@435 13 * accompanied this code).
duke@435 14 *
duke@435 15 * You should have received a copy of the GNU General Public License version
duke@435 16 * 2 along with this work; if not, write to the Free Software Foundation,
duke@435 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435 18 *
trims@1907 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907 20 * or visit www.oracle.com if you need additional information or have any
trims@1907 21 * questions.
duke@435 22 *
duke@435 23 */
duke@435 24
stefank@2314 25 #ifndef SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_ADJOININGVIRTUALSPACES_HPP
stefank@2314 26 #define SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_ADJOININGVIRTUALSPACES_HPP
stefank@2314 27
stefank@2314 28 #include "gc_implementation/parallelScavenge/psVirtualspace.hpp"
stefank@2314 29
duke@435 30
duke@435 31 // Contains two virtual spaces that each can individually span
duke@435 32 // most of the reserved region but committed parts of which
duke@435 33 // cannot overlap.
duke@435 34 //
duke@435 35 // +-------+ <--- high_boundary for H
duke@435 36 // | |
duke@435 37 // | H |
duke@435 38 // | |
duke@435 39 // | |
duke@435 40 // | |
duke@435 41 // --------- <--- low for H
duke@435 42 // | |
duke@435 43 // ========= <--- low_boundary for H, high_boundary for L
duke@435 44 // | |
duke@435 45 // | |
duke@435 46 // | |
duke@435 47 // --------- <--- high for L
duke@435 48 // | |
duke@435 49 // | L |
duke@435 50 // | |
duke@435 51 // | |
duke@435 52 // | |
duke@435 53 // +-------+ <--- low_boundary for L
duke@435 54 //
duke@435 55 // Each virtual space in the AdjoiningVirtualSpaces grows and shrink
duke@435 56 // within its reserved region (between the low_boundary and the
duke@435 57 // boundary) independently. If L want to grow above its high_boundary,
duke@435 58 // then the high_boundary of L and the low_boundary of H must be
duke@435 59 // moved up consistently. AdjoiningVirtualSpaces provide the
duke@435 60 // interfaces for moving the this boundary.
duke@435 61
duke@435 62 class AdjoiningVirtualSpaces {
duke@435 63 // space at the high end and the low end, respectively
duke@435 64 PSVirtualSpace* _high;
duke@435 65 PSVirtualSpace* _low;
duke@435 66
duke@435 67 // The reserved space spanned by the two spaces.
duke@435 68 ReservedSpace _reserved_space;
duke@435 69
duke@435 70 // The minimum byte size for the low space. It will not
duke@435 71 // be shrunk below this value.
duke@435 72 size_t _min_low_byte_size;
duke@435 73 // Same for the high space
duke@435 74 size_t _min_high_byte_size;
duke@435 75
duke@435 76 const size_t _alignment;
duke@435 77
duke@435 78 public:
duke@435 79 // Allocates two virtual spaces that will be located at the
duke@435 80 // high and low ends. Does no initialization.
duke@435 81 AdjoiningVirtualSpaces(ReservedSpace rs,
duke@435 82 size_t min_low_byte_size,
duke@435 83 size_t min_high_byte_size,
duke@435 84 size_t alignment);
duke@435 85
duke@435 86 // accessors
duke@435 87 PSVirtualSpace* high() { return _high; }
duke@435 88 PSVirtualSpace* low() { return _low; }
duke@435 89 ReservedSpace reserved_space() { return _reserved_space; }
duke@435 90 size_t min_low_byte_size() { return _min_low_byte_size; }
duke@435 91 size_t min_high_byte_size() { return _min_high_byte_size; }
duke@435 92 size_t alignment() const { return _alignment; }
duke@435 93
duke@435 94 // move boundary between the two spaces up
duke@435 95 bool adjust_boundary_up(size_t size_in_bytes);
duke@435 96 // and down
duke@435 97 bool adjust_boundary_down(size_t size_in_bytes);
duke@435 98
duke@435 99 // Maximum byte size for the high space.
duke@435 100 size_t high_byte_size_limit() {
duke@435 101 return _reserved_space.size() - _min_low_byte_size;
duke@435 102 }
duke@435 103 // Maximum byte size for the low space.
duke@435 104 size_t low_byte_size_limit() {
duke@435 105 return _reserved_space.size() - _min_high_byte_size;
duke@435 106 }
duke@435 107
duke@435 108 // Sets the boundaries for the virtual spaces and commits and
duke@435 109 // initial size;
duke@435 110 void initialize(size_t max_low_byte_size,
duke@435 111 size_t init_low_byte_size,
duke@435 112 size_t init_high_byte_size);
duke@435 113 };
stefank@2314 114
stefank@2314 115 #endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_ADJOININGVIRTUALSPACES_HPP

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