ysr@777: /*
xdono@905:  * Copyright 2001-2008 Sun Microsystems, Inc.  All Rights Reserved.
ysr@777:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
ysr@777:  *
ysr@777:  * This code is free software; you can redistribute it and/or modify it
ysr@777:  * under the terms of the GNU General Public License version 2 only, as
ysr@777:  * published by the Free Software Foundation.
ysr@777:  *
ysr@777:  * This code is distributed in the hope that it will be useful, but WITHOUT
ysr@777:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
ysr@777:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
ysr@777:  * version 2 for more details (a copy is included in the LICENSE file that
ysr@777:  * accompanied this code).
ysr@777:  *
ysr@777:  * You should have received a copy of the GNU General Public License version
ysr@777:  * 2 along with this work; if not, write to the Free Software Foundation,
ysr@777:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
ysr@777:  *
ysr@777:  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
ysr@777:  * CA 95054 USA or visit www.sun.com if you need additional information or
ysr@777:  * have any questions.
ysr@777:  *
ysr@777:  */
ysr@777: 
ysr@777: class HeapRegion;
ysr@777: class HeapRegionClosure;
ysr@777: 
ysr@777: class HeapRegionSeq: public CHeapObj {
ysr@777: 
ysr@777:   // _regions is kept sorted by start address order, and no two regions are
ysr@777:   // overlapping.
ysr@777:   GrowableArray<HeapRegion*> _regions;
ysr@777: 
ysr@777:   // The index in "_regions" at which to start the next allocation search.
ysr@777:   // (For efficiency only; private to obj_allocate after initialization.)
ysr@777:   int _alloc_search_start;
ysr@777: 
ysr@777:   // Attempts to allocate a block of the (assumed humongous) word_size,
ysr@777:   // starting at the region "ind".
ysr@777:   HeapWord* alloc_obj_from_region_index(int ind, size_t word_size);
ysr@777: 
ysr@777:   // Currently, we're choosing collection sets in a round-robin fashion,
ysr@777:   // starting here.
ysr@777:   int _next_rr_candidate;
ysr@777: 
ysr@777:   // The bottom address of the bottom-most region, or else NULL if there
ysr@777:   // are no regions in the sequence.
ysr@777:   char* _seq_bottom;
ysr@777: 
ysr@777:  public:
ysr@777:   // Initializes "this" to the empty sequence of regions.
iveresov@828:   HeapRegionSeq(const size_t max_size);
ysr@777: 
ysr@777:   // Adds "hr" to "this" sequence.  Requires "hr" not to overlap with
ysr@777:   // any region already in "this".  (Will perform better if regions are
ysr@777:   // inserted in ascending address order.)
ysr@777:   void insert(HeapRegion* hr);
ysr@777: 
ysr@777:   // Given a HeapRegion*, returns its index within _regions,
ysr@777:   // or returns -1 if not found.
ysr@777:   int find(HeapRegion* hr);
ysr@777: 
ysr@777:   // Requires the index to be valid, and return the region at the index.
ysr@777:   HeapRegion* at(size_t i) { return _regions.at((int)i); }
ysr@777: 
ysr@777:   // Return the number of regions in the sequence.
ysr@777:   size_t length();
ysr@777: 
ysr@777:   // Returns the number of contiguous regions at the end of the sequence
ysr@777:   // that are available for allocation.
ysr@777:   size_t free_suffix();
ysr@777: 
ysr@777:   // Requires "word_size" to be humongous (in the technical sense).  If
ysr@777:   // possible, allocates a contiguous subsequence of the heap regions to
ysr@777:   // satisfy the allocation, and returns the address of the beginning of
ysr@777:   // that sequence, otherwise returns NULL.
ysr@777:   HeapWord* obj_allocate(size_t word_size);
ysr@777: 
ysr@777:   // Apply the "doHeapRegion" method of "blk" to all regions in "this",
ysr@777:   // in address order, terminating the iteration early
ysr@777:   // if the "doHeapRegion" method returns "true".
ysr@777:   void iterate(HeapRegionClosure* blk);
ysr@777: 
ysr@777:   // Apply the "doHeapRegion" method of "blk" to all regions in "this",
ysr@777:   // starting at "r" (or first region, if "r" is NULL), in a circular
ysr@777:   // manner, terminating the iteration early if the "doHeapRegion" method
ysr@777:   // returns "true".
ysr@777:   void iterate_from(HeapRegion* r, HeapRegionClosure* blk);
ysr@777: 
ysr@777:   // As above, but start from a given index in the sequence
ysr@777:   // instead of a given heap region.
ysr@777:   void iterate_from(int idx, HeapRegionClosure* blk);
ysr@777: 
ysr@777:   // Requires "shrink_bytes" to be a multiple of the page size and heap
ysr@777:   // region granularity.  Deletes as many "rightmost" completely free heap
ysr@777:   // regions from the sequence as comprise shrink_bytes bytes.  Returns the
ysr@777:   // MemRegion indicating the region those regions comprised, and sets
ysr@777:   // "num_regions_deleted" to the number of regions deleted.
ysr@777:   MemRegion shrink_by(size_t shrink_bytes, size_t& num_regions_deleted);
ysr@777: 
ysr@777:   // If "addr" falls within a region in the sequence, return that region,
ysr@777:   // or else NULL.
ysr@777:   HeapRegion* addr_to_region(const void* addr);
ysr@777: 
ysr@777:   void print();
ysr@777: 
apetrusenko@1112:   // Prints out runs of empty regions.
apetrusenko@1112:   void print_empty_runs();
ysr@777: 
ysr@777: };