1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/vm/gc_implementation/g1/g1PageBasedVirtualSpace.hpp Thu Aug 21 11:47:10 2014 +0200
1.3 @@ -0,0 +1,111 @@
1.4 +/*
1.5 + * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.23 + * or visit www.oracle.com if you need additional information or have any
1.24 + * questions.
1.25 + *
1.26 + */
1.27 +
1.28 +#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1PAGEBASEDVIRTUALSPACE_HPP
1.29 +#define SHARE_VM_GC_IMPLEMENTATION_G1_G1PAGEBASEDVIRTUALSPACE_HPP
1.30 +
1.31 +#include "memory/allocation.hpp"
1.32 +#include "memory/memRegion.hpp"
1.33 +#include "runtime/virtualspace.hpp"
1.34 +#include "utilities/bitMap.hpp"
1.35 +
1.36 +// Virtual space management helper for a virtual space with an OS page allocation
1.37 +// granularity.
1.38 +// (De-)Allocation requests are always OS page aligned by passing a page index
1.39 +// and multiples of pages.
1.40 +// The implementation gives an error when trying to commit or uncommit pages that
1.41 +// have already been committed or uncommitted.
1.42 +class G1PageBasedVirtualSpace VALUE_OBJ_CLASS_SPEC {
1.43 + friend class VMStructs;
1.44 + private:
1.45 + // Reserved area addresses.
1.46 + char* _low_boundary;
1.47 + char* _high_boundary;
1.48 +
1.49 + // The commit/uncommit granularity in bytes.
1.50 + size_t _page_size;
1.51 +
1.52 + // Bitmap used for verification of commit/uncommit operations.
1.53 + BitMap _committed;
1.54 +
1.55 + // Indicates that the entire space has been committed and pinned in memory,
1.56 + // os::commit_memory() or os::uncommit_memory() have no function.
1.57 + bool _special;
1.58 +
1.59 + // Indicates whether the committed space should be executable.
1.60 + bool _executable;
1.61 +
1.62 + // Returns the index of the page which contains the given address.
1.63 + uintptr_t addr_to_page_index(char* addr) const;
1.64 + // Returns the address of the given page index.
1.65 + char* page_start(uintptr_t index);
1.66 + // Returns the byte size of the given number of pages.
1.67 + size_t byte_size_for_pages(size_t num);
1.68 +
1.69 + // Returns true if the entire area is backed by committed memory.
1.70 + bool is_area_committed(uintptr_t start, size_t size_in_pages) const;
1.71 + // Returns true if the entire area is not backed by committed memory.
1.72 + bool is_area_uncommitted(uintptr_t start, size_t size_in_pages) const;
1.73 +
1.74 + public:
1.75 +
1.76 + // Commit the given area of pages starting at start being size_in_pages large.
1.77 + MemRegion commit(uintptr_t start, size_t size_in_pages);
1.78 +
1.79 + // Uncommit the given area of pages starting at start being size_in_pages large.
1.80 + MemRegion uncommit(uintptr_t start, size_t size_in_pages);
1.81 +
1.82 + bool special() const { return _special; }
1.83 +
1.84 + // Initialization
1.85 + G1PageBasedVirtualSpace();
1.86 + bool initialize_with_granularity(ReservedSpace rs, size_t page_size);
1.87 +
1.88 + // Destruction
1.89 + ~G1PageBasedVirtualSpace();
1.90 +
1.91 + // Amount of reserved memory.
1.92 + size_t reserved_size() const;
1.93 + // Memory used in this virtual space.
1.94 + size_t committed_size() const;
1.95 + // Memory left to use/expand in this virtual space.
1.96 + size_t uncommitted_size() const;
1.97 +
1.98 + bool contains(const void* p) const;
1.99 +
1.100 + MemRegion reserved() {
1.101 + MemRegion x((HeapWord*)_low_boundary, reserved_size() / HeapWordSize);
1.102 + return x;
1.103 + }
1.104 +
1.105 + void release();
1.106 +
1.107 + void check_for_contiguity() PRODUCT_RETURN;
1.108 +
1.109 + // Debugging
1.110 + void print_on(outputStream* out) PRODUCT_RETURN;
1.111 + void print();
1.112 +};
1.113 +
1.114 +#endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1PAGEBASEDVIRTUALSPACE_HPP
