--- old/src/share/vm/gc_implementation/g1/heapRegionManager.hpp 2015-05-12 11:55:03.384308261 +0200 +++ /dev/null 2015-03-18 17:10:38.111854831 +0100 @@ -1,269 +0,0 @@ -/* - * Copyright (c) 2001, 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_HEAPREGIONMANAGER_HPP -#define SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONMANAGER_HPP - -#include "gc_implementation/g1/g1BiasedArray.hpp" -#include "gc_implementation/g1/g1RegionToSpaceMapper.hpp" -#include "gc_implementation/g1/heapRegionSet.hpp" -#include "services/memoryUsage.hpp" - -class HeapRegion; -class HeapRegionClosure; -class HeapRegionClaimer; -class FreeRegionList; - -class G1HeapRegionTable : public G1BiasedMappedArray { - protected: - virtual HeapRegion* default_value() const { return NULL; } -}; - -// This class keeps track of the actual heap memory, auxiliary data -// and its metadata (i.e., HeapRegion instances) and the list of free regions. -// -// This allows maximum flexibility for deciding what to commit or uncommit given -// a request from outside. -// -// HeapRegions are kept in the _regions array in address order. A region's -// index in the array corresponds to its index in the heap (i.e., 0 is the -// region at the bottom of the heap, 1 is the one after it, etc.). Two -// regions that are consecutive in the array should also be adjacent in the -// address space (i.e., region(i).end() == region(i+1).bottom(). -// -// We create a HeapRegion when we commit the region's address space -// for the first time. When we uncommit the address space of a -// region we retain the HeapRegion to be able to re-use it in the -// future (in case we recommit it). -// -// We keep track of three lengths: -// -// * _num_committed (returned by length()) is the number of currently -// committed regions. These may not be contiguous. -// * _allocated_heapregions_length (not exposed outside this class) is the -// number of regions+1 for which we have HeapRegions. -// * max_length() returns the maximum number of regions the heap can have. -// - -class HeapRegionManager: public CHeapObj { - friend class VMStructs; - friend class HeapRegionClaimer; - - G1HeapRegionTable _regions; - - G1RegionToSpaceMapper* _heap_mapper; - G1RegionToSpaceMapper* _prev_bitmap_mapper; - G1RegionToSpaceMapper* _next_bitmap_mapper; - G1RegionToSpaceMapper* _bot_mapper; - G1RegionToSpaceMapper* _cardtable_mapper; - G1RegionToSpaceMapper* _card_counts_mapper; - - FreeRegionList _free_list; - - // Each bit in this bitmap indicates that the corresponding region is available - // for allocation. - BitMap _available_map; - - // The number of regions committed in the heap. - uint _num_committed; - - // Internal only. The highest heap region +1 we allocated a HeapRegion instance for. - uint _allocated_heapregions_length; - - HeapWord* heap_bottom() const { return _regions.bottom_address_mapped(); } - HeapWord* heap_end() const {return _regions.end_address_mapped(); } - - void make_regions_available(uint index, uint num_regions = 1); - - // Pass down commit calls to the VirtualSpace. - void commit_regions(uint index, size_t num_regions = 1); - void uncommit_regions(uint index, size_t num_regions = 1); - - // Notify other data structures about change in the heap layout. - void update_committed_space(HeapWord* old_end, HeapWord* new_end); - - // Find a contiguous set of empty or uncommitted regions of length num and return - // the index of the first region or G1_NO_HRM_INDEX if the search was unsuccessful. - // If only_empty is true, only empty regions are considered. - // Searches from bottom to top of the heap, doing a first-fit. - uint find_contiguous(size_t num, bool only_empty); - // Finds the next sequence of unavailable regions starting from start_idx. Returns the - // length of the sequence found. If this result is zero, no such sequence could be found, - // otherwise res_idx indicates the start index of these regions. - uint find_unavailable_from_idx(uint start_idx, uint* res_idx) const; - // Finds the next sequence of empty regions starting from start_idx, going backwards in - // the heap. Returns the length of the sequence found. If this value is zero, no - // sequence could be found, otherwise res_idx contains the start index of this range. - uint find_empty_from_idx_reverse(uint start_idx, uint* res_idx) const; - // Allocate a new HeapRegion for the given index. - HeapRegion* new_heap_region(uint hrm_index); -#ifdef ASSERT -public: - bool is_free(HeapRegion* hr) const; -#endif - // Returns whether the given region is available for allocation. - bool is_available(uint region) const; - - public: - // Empty constructor, we'll initialize it with the initialize() method. - HeapRegionManager() : _regions(), _heap_mapper(NULL), _num_committed(0), - _next_bitmap_mapper(NULL), _prev_bitmap_mapper(NULL), _bot_mapper(NULL), - _allocated_heapregions_length(0), _available_map(), - _free_list("Free list", new MasterFreeRegionListMtSafeChecker()) - { } - - void initialize(G1RegionToSpaceMapper* heap_storage, - G1RegionToSpaceMapper* prev_bitmap, - G1RegionToSpaceMapper* next_bitmap, - G1RegionToSpaceMapper* bot, - G1RegionToSpaceMapper* cardtable, - G1RegionToSpaceMapper* card_counts); - - // Return the "dummy" region used for G1AllocRegion. This is currently a hardwired - // new HeapRegion that owns HeapRegion at index 0. Since at the moment we commit - // the heap from the lowest address, this region (and its associated data - // structures) are available and we do not need to check further. - HeapRegion* get_dummy_region() { return new_heap_region(0); } - - // Return the HeapRegion at the given index. Assume that the index - // is valid. - inline HeapRegion* at(uint index) const; - - // If addr is within the committed space return its corresponding - // HeapRegion, otherwise return NULL. - inline HeapRegion* addr_to_region(HeapWord* addr) const; - - // Insert the given region into the free region list. - inline void insert_into_free_list(HeapRegion* hr); - - // Insert the given region list into the global free region list. - void insert_list_into_free_list(FreeRegionList* list) { - _free_list.add_ordered(list); - } - - HeapRegion* allocate_free_region(bool is_old) { - HeapRegion* hr = _free_list.remove_region(is_old); - - if (hr != NULL) { - assert(hr->next() == NULL, "Single region should not have next"); - assert(is_available(hr->hrm_index()), "Must be committed"); - } - return hr; - } - - inline void allocate_free_regions_starting_at(uint first, uint num_regions); - - // Remove all regions from the free list. - void remove_all_free_regions() { - _free_list.remove_all(); - } - - // Return the number of committed free regions in the heap. - uint num_free_regions() const { - return _free_list.length(); - } - - size_t total_capacity_bytes() const { - return num_free_regions() * HeapRegion::GrainBytes; - } - - // Return the number of available (uncommitted) regions. - uint available() const { return max_length() - length(); } - - // Return the number of regions that have been committed in the heap. - uint length() const { return _num_committed; } - - // Return the maximum number of regions in the heap. - uint max_length() const { return (uint)_regions.length(); } - - MemoryUsage get_auxiliary_data_memory_usage() const; - - MemRegion reserved() const { return MemRegion(heap_bottom(), heap_end()); } - - // Expand the sequence to reflect that the heap has grown. Either create new - // HeapRegions, or re-use existing ones. Returns the number of regions the - // sequence was expanded by. If a HeapRegion allocation fails, the resulting - // number of regions might be smaller than what's desired. - uint expand_by(uint num_regions); - - // Makes sure that the regions from start to start+num_regions-1 are available - // for allocation. Returns the number of regions that were committed to achieve - // this. - uint expand_at(uint start, uint num_regions); - - // Find a contiguous set of empty regions of length num. Returns the start index of - // that set, or G1_NO_HRM_INDEX. - uint find_contiguous_only_empty(size_t num) { return find_contiguous(num, true); } - // Find a contiguous set of empty or unavailable regions of length num. Returns the - // start index of that set, or G1_NO_HRM_INDEX. - uint find_contiguous_empty_or_unavailable(size_t num) { return find_contiguous(num, false); } - - HeapRegion* next_region_in_heap(const HeapRegion* r) const; - - // Apply blk->doHeapRegion() on all committed regions in address order, - // terminating the iteration early if doHeapRegion() returns true. - void iterate(HeapRegionClosure* blk) const; - - void par_iterate(HeapRegionClosure* blk, uint worker_id, HeapRegionClaimer* hrclaimer, bool concurrent) const; - - // Uncommit up to num_regions_to_remove regions that are completely free. - // Return the actual number of uncommitted regions. - uint shrink_by(uint num_regions_to_remove); - - void verify(); - - // Do some sanity checking. - void verify_optional() PRODUCT_RETURN; -}; - -// The HeapRegionClaimer is used during parallel iteration over heap regions, -// allowing workers to claim heap regions, gaining exclusive rights to these regions. -class HeapRegionClaimer : public StackObj { - uint _n_workers; - uint _n_regions; - uint* _claims; - - static const uint Unclaimed = 0; - static const uint Claimed = 1; - - public: - HeapRegionClaimer(uint n_workers); - ~HeapRegionClaimer(); - - inline uint n_regions() const { - return _n_regions; - } - - // Calculate the starting region for given worker so - // that they do not all start from the same region. - uint start_region_for_worker(uint worker_id) const; - - // Check if region has been claimed with this HRClaimer. - bool is_region_claimed(uint region_index) const; - - // Claim the given region, returns true if successfully claimed. - bool claim_region(uint region_index); -}; -#endif // SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONMANAGER_HPP - --- /dev/null 2015-03-18 17:10:38.111854831 +0100 +++ new/src/share/vm/gc/g1/heapRegionManager.hpp 2015-05-12 11:55:03.194300318 +0200 @@ -0,0 +1,269 @@ +/* + * Copyright (c) 2001, 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_HEAPREGIONMANAGER_HPP +#define SHARE_VM_GC_G1_HEAPREGIONMANAGER_HPP + +#include "gc/g1/g1BiasedArray.hpp" +#include "gc/g1/g1RegionToSpaceMapper.hpp" +#include "gc/g1/heapRegionSet.hpp" +#include "services/memoryUsage.hpp" + +class HeapRegion; +class HeapRegionClosure; +class HeapRegionClaimer; +class FreeRegionList; + +class G1HeapRegionTable : public G1BiasedMappedArray { + protected: + virtual HeapRegion* default_value() const { return NULL; } +}; + +// This class keeps track of the actual heap memory, auxiliary data +// and its metadata (i.e., HeapRegion instances) and the list of free regions. +// +// This allows maximum flexibility for deciding what to commit or uncommit given +// a request from outside. +// +// HeapRegions are kept in the _regions array in address order. A region's +// index in the array corresponds to its index in the heap (i.e., 0 is the +// region at the bottom of the heap, 1 is the one after it, etc.). Two +// regions that are consecutive in the array should also be adjacent in the +// address space (i.e., region(i).end() == region(i+1).bottom(). +// +// We create a HeapRegion when we commit the region's address space +// for the first time. When we uncommit the address space of a +// region we retain the HeapRegion to be able to re-use it in the +// future (in case we recommit it). +// +// We keep track of three lengths: +// +// * _num_committed (returned by length()) is the number of currently +// committed regions. These may not be contiguous. +// * _allocated_heapregions_length (not exposed outside this class) is the +// number of regions+1 for which we have HeapRegions. +// * max_length() returns the maximum number of regions the heap can have. +// + +class HeapRegionManager: public CHeapObj { + friend class VMStructs; + friend class HeapRegionClaimer; + + G1HeapRegionTable _regions; + + G1RegionToSpaceMapper* _heap_mapper; + G1RegionToSpaceMapper* _prev_bitmap_mapper; + G1RegionToSpaceMapper* _next_bitmap_mapper; + G1RegionToSpaceMapper* _bot_mapper; + G1RegionToSpaceMapper* _cardtable_mapper; + G1RegionToSpaceMapper* _card_counts_mapper; + + FreeRegionList _free_list; + + // Each bit in this bitmap indicates that the corresponding region is available + // for allocation. + BitMap _available_map; + + // The number of regions committed in the heap. + uint _num_committed; + + // Internal only. The highest heap region +1 we allocated a HeapRegion instance for. + uint _allocated_heapregions_length; + + HeapWord* heap_bottom() const { return _regions.bottom_address_mapped(); } + HeapWord* heap_end() const {return _regions.end_address_mapped(); } + + void make_regions_available(uint index, uint num_regions = 1); + + // Pass down commit calls to the VirtualSpace. + void commit_regions(uint index, size_t num_regions = 1); + void uncommit_regions(uint index, size_t num_regions = 1); + + // Notify other data structures about change in the heap layout. + void update_committed_space(HeapWord* old_end, HeapWord* new_end); + + // Find a contiguous set of empty or uncommitted regions of length num and return + // the index of the first region or G1_NO_HRM_INDEX if the search was unsuccessful. + // If only_empty is true, only empty regions are considered. + // Searches from bottom to top of the heap, doing a first-fit. + uint find_contiguous(size_t num, bool only_empty); + // Finds the next sequence of unavailable regions starting from start_idx. Returns the + // length of the sequence found. If this result is zero, no such sequence could be found, + // otherwise res_idx indicates the start index of these regions. + uint find_unavailable_from_idx(uint start_idx, uint* res_idx) const; + // Finds the next sequence of empty regions starting from start_idx, going backwards in + // the heap. Returns the length of the sequence found. If this value is zero, no + // sequence could be found, otherwise res_idx contains the start index of this range. + uint find_empty_from_idx_reverse(uint start_idx, uint* res_idx) const; + // Allocate a new HeapRegion for the given index. + HeapRegion* new_heap_region(uint hrm_index); +#ifdef ASSERT +public: + bool is_free(HeapRegion* hr) const; +#endif + // Returns whether the given region is available for allocation. + bool is_available(uint region) const; + + public: + // Empty constructor, we'll initialize it with the initialize() method. + HeapRegionManager() : _regions(), _heap_mapper(NULL), _num_committed(0), + _next_bitmap_mapper(NULL), _prev_bitmap_mapper(NULL), _bot_mapper(NULL), + _allocated_heapregions_length(0), _available_map(), + _free_list("Free list", new MasterFreeRegionListMtSafeChecker()) + { } + + void initialize(G1RegionToSpaceMapper* heap_storage, + G1RegionToSpaceMapper* prev_bitmap, + G1RegionToSpaceMapper* next_bitmap, + G1RegionToSpaceMapper* bot, + G1RegionToSpaceMapper* cardtable, + G1RegionToSpaceMapper* card_counts); + + // Return the "dummy" region used for G1AllocRegion. This is currently a hardwired + // new HeapRegion that owns HeapRegion at index 0. Since at the moment we commit + // the heap from the lowest address, this region (and its associated data + // structures) are available and we do not need to check further. + HeapRegion* get_dummy_region() { return new_heap_region(0); } + + // Return the HeapRegion at the given index. Assume that the index + // is valid. + inline HeapRegion* at(uint index) const; + + // If addr is within the committed space return its corresponding + // HeapRegion, otherwise return NULL. + inline HeapRegion* addr_to_region(HeapWord* addr) const; + + // Insert the given region into the free region list. + inline void insert_into_free_list(HeapRegion* hr); + + // Insert the given region list into the global free region list. + void insert_list_into_free_list(FreeRegionList* list) { + _free_list.add_ordered(list); + } + + HeapRegion* allocate_free_region(bool is_old) { + HeapRegion* hr = _free_list.remove_region(is_old); + + if (hr != NULL) { + assert(hr->next() == NULL, "Single region should not have next"); + assert(is_available(hr->hrm_index()), "Must be committed"); + } + return hr; + } + + inline void allocate_free_regions_starting_at(uint first, uint num_regions); + + // Remove all regions from the free list. + void remove_all_free_regions() { + _free_list.remove_all(); + } + + // Return the number of committed free regions in the heap. + uint num_free_regions() const { + return _free_list.length(); + } + + size_t total_capacity_bytes() const { + return num_free_regions() * HeapRegion::GrainBytes; + } + + // Return the number of available (uncommitted) regions. + uint available() const { return max_length() - length(); } + + // Return the number of regions that have been committed in the heap. + uint length() const { return _num_committed; } + + // Return the maximum number of regions in the heap. + uint max_length() const { return (uint)_regions.length(); } + + MemoryUsage get_auxiliary_data_memory_usage() const; + + MemRegion reserved() const { return MemRegion(heap_bottom(), heap_end()); } + + // Expand the sequence to reflect that the heap has grown. Either create new + // HeapRegions, or re-use existing ones. Returns the number of regions the + // sequence was expanded by. If a HeapRegion allocation fails, the resulting + // number of regions might be smaller than what's desired. + uint expand_by(uint num_regions); + + // Makes sure that the regions from start to start+num_regions-1 are available + // for allocation. Returns the number of regions that were committed to achieve + // this. + uint expand_at(uint start, uint num_regions); + + // Find a contiguous set of empty regions of length num. Returns the start index of + // that set, or G1_NO_HRM_INDEX. + uint find_contiguous_only_empty(size_t num) { return find_contiguous(num, true); } + // Find a contiguous set of empty or unavailable regions of length num. Returns the + // start index of that set, or G1_NO_HRM_INDEX. + uint find_contiguous_empty_or_unavailable(size_t num) { return find_contiguous(num, false); } + + HeapRegion* next_region_in_heap(const HeapRegion* r) const; + + // Apply blk->doHeapRegion() on all committed regions in address order, + // terminating the iteration early if doHeapRegion() returns true. + void iterate(HeapRegionClosure* blk) const; + + void par_iterate(HeapRegionClosure* blk, uint worker_id, HeapRegionClaimer* hrclaimer, bool concurrent) const; + + // Uncommit up to num_regions_to_remove regions that are completely free. + // Return the actual number of uncommitted regions. + uint shrink_by(uint num_regions_to_remove); + + void verify(); + + // Do some sanity checking. + void verify_optional() PRODUCT_RETURN; +}; + +// The HeapRegionClaimer is used during parallel iteration over heap regions, +// allowing workers to claim heap regions, gaining exclusive rights to these regions. +class HeapRegionClaimer : public StackObj { + uint _n_workers; + uint _n_regions; + uint* _claims; + + static const uint Unclaimed = 0; + static const uint Claimed = 1; + + public: + HeapRegionClaimer(uint n_workers); + ~HeapRegionClaimer(); + + inline uint n_regions() const { + return _n_regions; + } + + // Calculate the starting region for given worker so + // that they do not all start from the same region. + uint start_region_for_worker(uint worker_id) const; + + // Check if region has been claimed with this HRClaimer. + bool is_region_claimed(uint region_index) const; + + // Claim the given region, returns true if successfully claimed. + bool claim_region(uint region_index); +}; +#endif // SHARE_VM_GC_G1_HEAPREGIONMANAGER_HPP +