--- old/src/share/vm/gc_implementation/g1/g1PageBasedVirtualSpace.hpp 2015-05-12 11:54:37.160212037 +0200 +++ /dev/null 2015-03-18 17:10:38.111854831 +0100 @@ -1,151 +0,0 @@ -/* - * 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_IMPLEMENTATION_G1_G1PAGEBASEDVIRTUALSPACE_HPP -#define SHARE_VM_GC_IMPLEMENTATION_G1_G1PAGEBASEDVIRTUALSPACE_HPP - -#include "memory/allocation.hpp" -#include "memory/memRegion.hpp" -#include "memory/virtualspace.hpp" -#include "utilities/bitMap.hpp" - -// Virtual space management helper for a virtual space with an OS page allocation -// granularity. -// (De-)Allocation requests are always OS page aligned by passing a page index -// and multiples of pages. -// For systems that only commits of memory in a given size (always greater than -// page size) the base address is required to be aligned to that page size. -// The actual size requested need not be aligned to that page size, but the size -// of the reservation passed may be rounded up to this page size. Any fragment -// (less than the page size) of the actual size at the tail of the request will -// be committed using OS small pages. -// The implementation gives an error when trying to commit or uncommit pages that -// have already been committed or uncommitted. -class G1PageBasedVirtualSpace VALUE_OBJ_CLASS_SPEC { - friend class VMStructs; - private: - // Reserved area addresses. - char* _low_boundary; - char* _high_boundary; - - // The size of the tail in bytes of the handled space that needs to be committed - // using small pages. - size_t _tail_size; - - // The preferred page size used for commit/uncommit in bytes. - size_t _page_size; - - // Bitmap used for verification of commit/uncommit operations. - BitMap _committed; - - // Bitmap used to keep track of which pages are dirty or not for _special - // spaces. This is needed because for those spaces the underlying memory - // will only be zero filled the first time it is committed. Calls to commit - // will use this bitmap and return whether or not the memory is zero filled. - BitMap _dirty; - - // Indicates that the entire space has been committed and pinned in memory, - // os::commit_memory() or os::uncommit_memory() have no function. - bool _special; - - // Indicates whether the committed space should be executable. - bool _executable; - - // Helper function for committing memory. Commit the given memory range by using - // _page_size pages as much as possible and the remainder with small sized pages. - void commit_internal(size_t start_page, size_t end_page); - // Commit num_pages pages of _page_size size starting from start. All argument - // checking has been performed. - void commit_preferred_pages(size_t start_page, size_t end_page); - // Commit space at the high end of the space that needs to be committed with small - // sized pages. - void commit_tail(); - - // Uncommit the given memory range. - void uncommit_internal(size_t start_page, size_t end_page); - - // Pretouch the given memory range. - void pretouch_internal(size_t start_page, size_t end_page); - - // Returns the index of the page which contains the given address. - uintptr_t addr_to_page_index(char* addr) const; - // Returns the address of the given page index. - char* page_start(size_t index) const; - - // Is the given page index the last page? - bool is_last_page(size_t index) const { return index == (_committed.size() - 1); } - // Is the given page index the first after last page? - bool is_after_last_page(size_t index) const; - // Is the last page only partially covered by this space? - bool is_last_page_partial() const { return !is_ptr_aligned(_high_boundary, _page_size); } - // Returns the end address of the given page bounded by the reserved space. - char* bounded_end_addr(size_t end_page) const; - - // Returns true if the entire area is backed by committed memory. - bool is_area_committed(size_t start_page, size_t size_in_pages) const; - // Returns true if the entire area is not backed by committed memory. - bool is_area_uncommitted(size_t start_page, size_t size_in_pages) const; - - void initialize_with_page_size(ReservedSpace rs, size_t used_size, size_t page_size); - public: - - // Commit the given area of pages starting at start being size_in_pages large. - // Returns true if the given area is zero filled upon completion. - bool commit(size_t start_page, size_t size_in_pages); - - // Uncommit the given area of pages starting at start being size_in_pages large. - void uncommit(size_t start_page, size_t size_in_pages); - - // Initialize the given reserved space with the given base address and the size - // actually used. - // Prefer to commit in page_size chunks. - G1PageBasedVirtualSpace(ReservedSpace rs, size_t used_size, size_t page_size); - - // Destruction - ~G1PageBasedVirtualSpace(); - - // Amount of reserved memory. - size_t reserved_size() const; - // Memory used in this virtual space. - size_t committed_size() const; - // Memory left to use/expand in this virtual space. - size_t uncommitted_size() const; - - bool contains(const void* p) const; - - MemRegion reserved() { - MemRegion x((HeapWord*)_low_boundary, reserved_size() / HeapWordSize); - return x; - } - - void release(); - - void check_for_contiguity() PRODUCT_RETURN; - - // Debugging - void print_on(outputStream* out) PRODUCT_RETURN; - void print(); -}; - -#endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1PAGEBASEDVIRTUALSPACE_HPP --- /dev/null 2015-03-18 17:10:38.111854831 +0100 +++ new/src/share/vm/gc/g1/g1PageBasedVirtualSpace.hpp 2015-05-12 11:54:36.951203300 +0200 @@ -0,0 +1,151 @@ +/* + * 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_G1_G1PAGEBASEDVIRTUALSPACE_HPP +#define SHARE_VM_GC_G1_G1PAGEBASEDVIRTUALSPACE_HPP + +#include "memory/allocation.hpp" +#include "memory/memRegion.hpp" +#include "memory/virtualspace.hpp" +#include "utilities/bitMap.hpp" + +// Virtual space management helper for a virtual space with an OS page allocation +// granularity. +// (De-)Allocation requests are always OS page aligned by passing a page index +// and multiples of pages. +// For systems that only commits of memory in a given size (always greater than +// page size) the base address is required to be aligned to that page size. +// The actual size requested need not be aligned to that page size, but the size +// of the reservation passed may be rounded up to this page size. Any fragment +// (less than the page size) of the actual size at the tail of the request will +// be committed using OS small pages. +// The implementation gives an error when trying to commit or uncommit pages that +// have already been committed or uncommitted. +class G1PageBasedVirtualSpace VALUE_OBJ_CLASS_SPEC { + friend class VMStructs; + private: + // Reserved area addresses. + char* _low_boundary; + char* _high_boundary; + + // The size of the tail in bytes of the handled space that needs to be committed + // using small pages. + size_t _tail_size; + + // The preferred page size used for commit/uncommit in bytes. + size_t _page_size; + + // Bitmap used for verification of commit/uncommit operations. + BitMap _committed; + + // Bitmap used to keep track of which pages are dirty or not for _special + // spaces. This is needed because for those spaces the underlying memory + // will only be zero filled the first time it is committed. Calls to commit + // will use this bitmap and return whether or not the memory is zero filled. + BitMap _dirty; + + // Indicates that the entire space has been committed and pinned in memory, + // os::commit_memory() or os::uncommit_memory() have no function. + bool _special; + + // Indicates whether the committed space should be executable. + bool _executable; + + // Helper function for committing memory. Commit the given memory range by using + // _page_size pages as much as possible and the remainder with small sized pages. + void commit_internal(size_t start_page, size_t end_page); + // Commit num_pages pages of _page_size size starting from start. All argument + // checking has been performed. + void commit_preferred_pages(size_t start_page, size_t end_page); + // Commit space at the high end of the space that needs to be committed with small + // sized pages. + void commit_tail(); + + // Uncommit the given memory range. + void uncommit_internal(size_t start_page, size_t end_page); + + // Pretouch the given memory range. + void pretouch_internal(size_t start_page, size_t end_page); + + // Returns the index of the page which contains the given address. + uintptr_t addr_to_page_index(char* addr) const; + // Returns the address of the given page index. + char* page_start(size_t index) const; + + // Is the given page index the last page? + bool is_last_page(size_t index) const { return index == (_committed.size() - 1); } + // Is the given page index the first after last page? + bool is_after_last_page(size_t index) const; + // Is the last page only partially covered by this space? + bool is_last_page_partial() const { return !is_ptr_aligned(_high_boundary, _page_size); } + // Returns the end address of the given page bounded by the reserved space. + char* bounded_end_addr(size_t end_page) const; + + // Returns true if the entire area is backed by committed memory. + bool is_area_committed(size_t start_page, size_t size_in_pages) const; + // Returns true if the entire area is not backed by committed memory. + bool is_area_uncommitted(size_t start_page, size_t size_in_pages) const; + + void initialize_with_page_size(ReservedSpace rs, size_t used_size, size_t page_size); + public: + + // Commit the given area of pages starting at start being size_in_pages large. + // Returns true if the given area is zero filled upon completion. + bool commit(size_t start_page, size_t size_in_pages); + + // Uncommit the given area of pages starting at start being size_in_pages large. + void uncommit(size_t start_page, size_t size_in_pages); + + // Initialize the given reserved space with the given base address and the size + // actually used. + // Prefer to commit in page_size chunks. + G1PageBasedVirtualSpace(ReservedSpace rs, size_t used_size, size_t page_size); + + // Destruction + ~G1PageBasedVirtualSpace(); + + // Amount of reserved memory. + size_t reserved_size() const; + // Memory used in this virtual space. + size_t committed_size() const; + // Memory left to use/expand in this virtual space. + size_t uncommitted_size() const; + + bool contains(const void* p) const; + + MemRegion reserved() { + MemRegion x((HeapWord*)_low_boundary, reserved_size() / HeapWordSize); + return x; + } + + void release(); + + void check_for_contiguity() PRODUCT_RETURN; + + // Debugging + void print_on(outputStream* out) PRODUCT_RETURN; + void print(); +}; + +#endif // SHARE_VM_GC_G1_G1PAGEBASEDVIRTUALSPACE_HPP