Tue, 26 Jan 2010 16:52:29 -0800
6920090: G1: Disable ReduceInitialCardMarks at least until 6920109 is fixed
Summary: G1 now answers "no" to the query can_elide_initializing_store_barrier() in the product build. A debug flag allows alternate behaviour in debug builds.
Reviewed-by: iveresov, tonyp
ysr@777 | 1 | /* |
xdono@1279 | 2 | * Copyright 2001-2009 Sun Microsystems, Inc. All Rights Reserved. |
ysr@777 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
ysr@777 | 4 | * |
ysr@777 | 5 | * This code is free software; you can redistribute it and/or modify it |
ysr@777 | 6 | * under the terms of the GNU General Public License version 2 only, as |
ysr@777 | 7 | * published by the Free Software Foundation. |
ysr@777 | 8 | * |
ysr@777 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
ysr@777 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
ysr@777 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
ysr@777 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
ysr@777 | 13 | * accompanied this code). |
ysr@777 | 14 | * |
ysr@777 | 15 | * You should have received a copy of the GNU General Public License version |
ysr@777 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
ysr@777 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
ysr@777 | 18 | * |
ysr@777 | 19 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
ysr@777 | 20 | * CA 95054 USA or visit www.sun.com if you need additional information or |
ysr@777 | 21 | * have any questions. |
ysr@777 | 22 | * |
ysr@777 | 23 | */ |
ysr@777 | 24 | |
ysr@777 | 25 | class HeapRegion; |
ysr@777 | 26 | class HeapRegionClosure; |
ysr@777 | 27 | |
ysr@777 | 28 | class HeapRegionSeq: public CHeapObj { |
ysr@777 | 29 | |
ysr@777 | 30 | // _regions is kept sorted by start address order, and no two regions are |
ysr@777 | 31 | // overlapping. |
ysr@777 | 32 | GrowableArray<HeapRegion*> _regions; |
ysr@777 | 33 | |
ysr@777 | 34 | // The index in "_regions" at which to start the next allocation search. |
ysr@777 | 35 | // (For efficiency only; private to obj_allocate after initialization.) |
ysr@777 | 36 | int _alloc_search_start; |
ysr@777 | 37 | |
ysr@777 | 38 | // Attempts to allocate a block of the (assumed humongous) word_size, |
ysr@777 | 39 | // starting at the region "ind". |
ysr@777 | 40 | HeapWord* alloc_obj_from_region_index(int ind, size_t word_size); |
ysr@777 | 41 | |
ysr@777 | 42 | // Currently, we're choosing collection sets in a round-robin fashion, |
ysr@777 | 43 | // starting here. |
ysr@777 | 44 | int _next_rr_candidate; |
ysr@777 | 45 | |
ysr@777 | 46 | // The bottom address of the bottom-most region, or else NULL if there |
ysr@777 | 47 | // are no regions in the sequence. |
ysr@777 | 48 | char* _seq_bottom; |
ysr@777 | 49 | |
ysr@777 | 50 | public: |
ysr@777 | 51 | // Initializes "this" to the empty sequence of regions. |
iveresov@828 | 52 | HeapRegionSeq(const size_t max_size); |
ysr@777 | 53 | |
ysr@777 | 54 | // Adds "hr" to "this" sequence. Requires "hr" not to overlap with |
ysr@777 | 55 | // any region already in "this". (Will perform better if regions are |
ysr@777 | 56 | // inserted in ascending address order.) |
ysr@777 | 57 | void insert(HeapRegion* hr); |
ysr@777 | 58 | |
ysr@777 | 59 | // Given a HeapRegion*, returns its index within _regions, |
ysr@777 | 60 | // or returns -1 if not found. |
ysr@777 | 61 | int find(HeapRegion* hr); |
ysr@777 | 62 | |
ysr@777 | 63 | // Requires the index to be valid, and return the region at the index. |
ysr@777 | 64 | HeapRegion* at(size_t i) { return _regions.at((int)i); } |
ysr@777 | 65 | |
ysr@777 | 66 | // Return the number of regions in the sequence. |
ysr@777 | 67 | size_t length(); |
ysr@777 | 68 | |
ysr@777 | 69 | // Returns the number of contiguous regions at the end of the sequence |
ysr@777 | 70 | // that are available for allocation. |
ysr@777 | 71 | size_t free_suffix(); |
ysr@777 | 72 | |
ysr@777 | 73 | // Requires "word_size" to be humongous (in the technical sense). If |
ysr@777 | 74 | // possible, allocates a contiguous subsequence of the heap regions to |
ysr@777 | 75 | // satisfy the allocation, and returns the address of the beginning of |
ysr@777 | 76 | // that sequence, otherwise returns NULL. |
ysr@777 | 77 | HeapWord* obj_allocate(size_t word_size); |
ysr@777 | 78 | |
ysr@777 | 79 | // Apply the "doHeapRegion" method of "blk" to all regions in "this", |
ysr@777 | 80 | // in address order, terminating the iteration early |
ysr@777 | 81 | // if the "doHeapRegion" method returns "true". |
ysr@777 | 82 | void iterate(HeapRegionClosure* blk); |
ysr@777 | 83 | |
ysr@777 | 84 | // Apply the "doHeapRegion" method of "blk" to all regions in "this", |
ysr@777 | 85 | // starting at "r" (or first region, if "r" is NULL), in a circular |
ysr@777 | 86 | // manner, terminating the iteration early if the "doHeapRegion" method |
ysr@777 | 87 | // returns "true". |
ysr@777 | 88 | void iterate_from(HeapRegion* r, HeapRegionClosure* blk); |
ysr@777 | 89 | |
ysr@777 | 90 | // As above, but start from a given index in the sequence |
ysr@777 | 91 | // instead of a given heap region. |
ysr@777 | 92 | void iterate_from(int idx, HeapRegionClosure* blk); |
ysr@777 | 93 | |
ysr@777 | 94 | // Requires "shrink_bytes" to be a multiple of the page size and heap |
ysr@777 | 95 | // region granularity. Deletes as many "rightmost" completely free heap |
ysr@777 | 96 | // regions from the sequence as comprise shrink_bytes bytes. Returns the |
ysr@777 | 97 | // MemRegion indicating the region those regions comprised, and sets |
ysr@777 | 98 | // "num_regions_deleted" to the number of regions deleted. |
ysr@777 | 99 | MemRegion shrink_by(size_t shrink_bytes, size_t& num_regions_deleted); |
ysr@777 | 100 | |
ysr@777 | 101 | // If "addr" falls within a region in the sequence, return that region, |
ysr@777 | 102 | // or else NULL. |
ysr@777 | 103 | HeapRegion* addr_to_region(const void* addr); |
ysr@777 | 104 | |
ysr@777 | 105 | void print(); |
ysr@777 | 106 | |
apetrusenko@1112 | 107 | // Prints out runs of empty regions. |
apetrusenko@1112 | 108 | void print_empty_runs(); |
ysr@777 | 109 | |
ysr@777 | 110 | }; |