Mercurial > hg > graal-jvmci-8
diff src/share/vm/gc_implementation/g1/heapRegionManager.hpp @ 20377:a8ea2f110d87
8054819: Rename HeapRegionSeq to HeapRegionManager
Reviewed-by: jwilhelm, jmasa
author | tschatzl |
---|---|
date | Tue, 26 Aug 2014 09:36:53 +0200 |
parents | src/share/vm/gc_implementation/g1/heapRegionSeq.hpp@1f1d373cd044 |
children | 7848fc12602b e5406a79ae90 |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/gc_implementation/g1/heapRegionManager.hpp Tue Aug 26 09:36:53 2014 +0200 @@ -0,0 +1,238 @@ +/* + * Copyright (c) 2001, 2013, 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" + +class HeapRegion; +class HeapRegionClosure; +class FreeRegionList; + +class G1HeapRegionTable : public G1BiasedMappedArray<HeapRegion*> { + 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<mtGC> { + friend class VMStructs; + + 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); + // Calculate the starting region for each worker during parallel iteration so + // that they do not all start from the same region. + uint start_region_for_worker(uint worker_i, uint num_workers, uint num_regions) const; + + // 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(); } + + 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, uint no_of_par_workers, jint claim_value) 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; +}; + +#endif // SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONMANAGER_HPP