src/share/vm/gc_implementation/concurrentMarkSweep/binaryTreeDictionary.hpp

Thu, 27 May 2010 19:08:38 -0700

author
trims
date
Thu, 27 May 2010 19:08:38 -0700
changeset 1907
c18cbe5936b8
parent 1580
e018e6884bd8
child 2314
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6941466: Oracle rebranding changes for Hotspot repositories
Summary: Change all the Sun copyrights to Oracle copyright
Reviewed-by: ohair

duke@435 1 /*
trims@1907 2 * Copyright (c) 2001, 2008, Oracle and/or its affiliates. All rights reserved.
duke@435 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435 4 *
duke@435 5 * This code is free software; you can redistribute it and/or modify it
duke@435 6 * under the terms of the GNU General Public License version 2 only, as
duke@435 7 * published by the Free Software Foundation.
duke@435 8 *
duke@435 9 * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@435 12 * version 2 for more details (a copy is included in the LICENSE file that
duke@435 13 * accompanied this code).
duke@435 14 *
duke@435 15 * You should have received a copy of the GNU General Public License version
duke@435 16 * 2 along with this work; if not, write to the Free Software Foundation,
duke@435 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435 18 *
trims@1907 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907 20 * or visit www.oracle.com if you need additional information or have any
trims@1907 21 * questions.
duke@435 22 *
duke@435 23 */
duke@435 24
duke@435 25 /*
duke@435 26 * A binary tree based search structure for free blocks.
duke@435 27 * This is currently used in the Concurrent Mark&Sweep implementation.
duke@435 28 */
duke@435 29
duke@435 30 // A TreeList is a FreeList which can be used to maintain a
duke@435 31 // binary tree of free lists.
duke@435 32
duke@435 33 class TreeChunk;
duke@435 34 class BinaryTreeDictionary;
duke@435 35 class AscendTreeCensusClosure;
duke@435 36 class DescendTreeCensusClosure;
duke@435 37 class DescendTreeSearchClosure;
duke@435 38
duke@435 39 class TreeList: public FreeList {
duke@435 40 friend class TreeChunk;
duke@435 41 friend class BinaryTreeDictionary;
duke@435 42 friend class AscendTreeCensusClosure;
duke@435 43 friend class DescendTreeCensusClosure;
duke@435 44 friend class DescendTreeSearchClosure;
duke@435 45
duke@435 46 protected:
duke@435 47 TreeList* parent() const { return _parent; }
duke@435 48 TreeList* left() const { return _left; }
duke@435 49 TreeList* right() const { return _right; }
duke@435 50
duke@435 51 // Accessors for links in tree.
duke@435 52
duke@435 53 void setLeft(TreeList* tl) {
duke@435 54 _left = tl;
duke@435 55 if (tl != NULL)
duke@435 56 tl->setParent(this);
duke@435 57 }
duke@435 58 void setRight(TreeList* tl) {
duke@435 59 _right = tl;
duke@435 60 if (tl != NULL)
duke@435 61 tl->setParent(this);
duke@435 62 }
duke@435 63 void setParent(TreeList* tl) { _parent = tl; }
duke@435 64
duke@435 65 void clearLeft() { _left = NULL; }
duke@435 66 void clearRight() { _right = NULL; }
duke@435 67 void clearParent() { _parent = NULL; }
duke@435 68 void initialize() { clearLeft(); clearRight(), clearParent(); }
duke@435 69
duke@435 70 // For constructing a TreeList from a Tree chunk or
duke@435 71 // address and size.
duke@435 72 static TreeList* as_TreeList(TreeChunk* tc);
duke@435 73 static TreeList* as_TreeList(HeapWord* addr, size_t size);
duke@435 74
duke@435 75 // Returns the head of the free list as a pointer to a TreeChunk.
duke@435 76 TreeChunk* head_as_TreeChunk();
duke@435 77
duke@435 78 // Returns the first available chunk in the free list as a pointer
duke@435 79 // to a TreeChunk.
duke@435 80 TreeChunk* first_available();
duke@435 81
ysr@1580 82 // Returns the block with the largest heap address amongst
ysr@1580 83 // those in the list for this size; potentially slow and expensive,
ysr@1580 84 // use with caution!
ysr@1580 85 TreeChunk* largest_address();
ysr@1580 86
duke@435 87 // removeChunkReplaceIfNeeded() removes the given "tc" from the TreeList.
duke@435 88 // If "tc" is the first chunk in the list, it is also the
duke@435 89 // TreeList that is the node in the tree. removeChunkReplaceIfNeeded()
duke@435 90 // returns the possibly replaced TreeList* for the node in
duke@435 91 // the tree. It also updates the parent of the original
duke@435 92 // node to point to the new node.
duke@435 93 TreeList* removeChunkReplaceIfNeeded(TreeChunk* tc);
duke@435 94 // See FreeList.
duke@435 95 void returnChunkAtHead(TreeChunk* tc);
duke@435 96 void returnChunkAtTail(TreeChunk* tc);
duke@435 97 };
duke@435 98
duke@435 99 // A TreeChunk is a subclass of a FreeChunk that additionally
duke@435 100 // maintains a pointer to the free list on which it is currently
duke@435 101 // linked.
duke@435 102 // A TreeChunk is also used as a node in the binary tree. This
duke@435 103 // allows the binary tree to be maintained without any additional
duke@435 104 // storage (the free chunks are used). In a binary tree the first
duke@435 105 // chunk in the free list is also the tree node. Note that the
duke@435 106 // TreeChunk has an embedded TreeList for this purpose. Because
duke@435 107 // the first chunk in the list is distinguished in this fashion
duke@435 108 // (also is the node in the tree), it is the last chunk to be found
duke@435 109 // on the free list for a node in the tree and is only removed if
duke@435 110 // it is the last chunk on the free list.
duke@435 111
duke@435 112 class TreeChunk : public FreeChunk {
duke@435 113 friend class TreeList;
duke@435 114 TreeList* _list;
duke@435 115 TreeList _embedded_list; // if non-null, this chunk is on _list
duke@435 116 protected:
duke@435 117 TreeList* embedded_list() const { return (TreeList*) &_embedded_list; }
duke@435 118 void set_embedded_list(TreeList* v) { _embedded_list = *v; }
duke@435 119 public:
duke@435 120 TreeList* list() { return _list; }
duke@435 121 void set_list(TreeList* v) { _list = v; }
duke@435 122 static TreeChunk* as_TreeChunk(FreeChunk* fc);
duke@435 123 // Initialize fields in a TreeChunk that should be
duke@435 124 // initialized when the TreeChunk is being added to
duke@435 125 // a free list in the tree.
duke@435 126 void initialize() { embedded_list()->initialize(); }
duke@435 127
duke@435 128 // debugging
duke@435 129 void verifyTreeChunkList() const;
duke@435 130 };
duke@435 131
duke@435 132 const size_t MIN_TREE_CHUNK_SIZE = sizeof(TreeChunk)/HeapWordSize;
duke@435 133
duke@435 134 class BinaryTreeDictionary: public FreeBlockDictionary {
dcubed@587 135 friend class VMStructs;
duke@435 136 bool _splay;
duke@435 137 size_t _totalSize;
duke@435 138 size_t _totalFreeBlocks;
duke@435 139 TreeList* _root;
duke@435 140
duke@435 141 // private accessors
duke@435 142 bool splay() const { return _splay; }
duke@435 143 void set_splay(bool v) { _splay = v; }
duke@435 144 size_t totalSize() const { return _totalSize; }
duke@435 145 void set_totalSize(size_t v) { _totalSize = v; }
duke@435 146 virtual void inc_totalSize(size_t v);
duke@435 147 virtual void dec_totalSize(size_t v);
duke@435 148 size_t totalFreeBlocks() const { return _totalFreeBlocks; }
duke@435 149 void set_totalFreeBlocks(size_t v) { _totalFreeBlocks = v; }
duke@435 150 TreeList* root() const { return _root; }
duke@435 151 void set_root(TreeList* v) { _root = v; }
duke@435 152
duke@435 153 // Remove a chunk of size "size" or larger from the tree and
duke@435 154 // return it. If the chunk
duke@435 155 // is the last chunk of that size, remove the node for that size
duke@435 156 // from the tree.
duke@435 157 TreeChunk* getChunkFromTree(size_t size, Dither dither, bool splay);
duke@435 158 // Return a list of the specified size or NULL from the tree.
duke@435 159 // The list is not removed from the tree.
duke@435 160 TreeList* findList (size_t size) const;
duke@435 161 // Remove this chunk from the tree. If the removal results
duke@435 162 // in an empty list in the tree, remove the empty list.
duke@435 163 TreeChunk* removeChunkFromTree(TreeChunk* tc);
duke@435 164 // Remove the node in the trees starting at tl that has the
duke@435 165 // minimum value and return it. Repair the tree as needed.
duke@435 166 TreeList* removeTreeMinimum(TreeList* tl);
duke@435 167 void semiSplayStep(TreeList* tl);
duke@435 168 // Add this free chunk to the tree.
duke@435 169 void insertChunkInTree(FreeChunk* freeChunk);
duke@435 170 public:
duke@435 171 void verifyTree() const;
duke@435 172 // verify that the given chunk is in the tree.
duke@435 173 bool verifyChunkInFreeLists(FreeChunk* tc) const;
duke@435 174 private:
duke@435 175 void verifyTreeHelper(TreeList* tl) const;
duke@435 176 static size_t verifyPrevFreePtrs(TreeList* tl);
duke@435 177
duke@435 178 // Returns the total number of chunks in the list.
duke@435 179 size_t totalListLength(TreeList* tl) const;
duke@435 180 // Returns the total number of words in the chunks in the tree
duke@435 181 // starting at "tl".
duke@435 182 size_t totalSizeInTree(TreeList* tl) const;
duke@435 183 // Returns the sum of the square of the size of each block
duke@435 184 // in the tree starting at "tl".
duke@435 185 double sum_of_squared_block_sizes(TreeList* const tl) const;
duke@435 186 // Returns the total number of free blocks in the tree starting
duke@435 187 // at "tl".
duke@435 188 size_t totalFreeBlocksInTree(TreeList* tl) const;
duke@435 189 size_t numFreeBlocks() const;
duke@435 190 size_t treeHeight() const;
duke@435 191 size_t treeHeightHelper(TreeList* tl) const;
duke@435 192 size_t totalNodesInTree(TreeList* tl) const;
duke@435 193 size_t totalNodesHelper(TreeList* tl) const;
duke@435 194
duke@435 195 public:
duke@435 196 // Constructor
duke@435 197 BinaryTreeDictionary(MemRegion mr, bool splay = false);
duke@435 198
duke@435 199 // Reset the dictionary to the initial conditions with
duke@435 200 // a single free chunk.
duke@435 201 void reset(MemRegion mr);
duke@435 202 void reset(HeapWord* addr, size_t size);
duke@435 203 // Reset the dictionary to be empty.
duke@435 204 void reset();
duke@435 205
duke@435 206 // Return a chunk of size "size" or greater from
duke@435 207 // the tree.
duke@435 208 // want a better dynamic splay strategy for the future.
duke@435 209 FreeChunk* getChunk(size_t size, Dither dither) {
duke@435 210 verify_par_locked();
duke@435 211 FreeChunk* res = getChunkFromTree(size, dither, splay());
duke@435 212 assert(res == NULL || res->isFree(),
duke@435 213 "Should be returning a free chunk");
duke@435 214 return res;
duke@435 215 }
duke@435 216
duke@435 217 void returnChunk(FreeChunk* chunk) {
duke@435 218 verify_par_locked();
duke@435 219 insertChunkInTree(chunk);
duke@435 220 }
duke@435 221
duke@435 222 void removeChunk(FreeChunk* chunk) {
duke@435 223 verify_par_locked();
duke@435 224 removeChunkFromTree((TreeChunk*)chunk);
duke@435 225 assert(chunk->isFree(), "Should still be a free chunk");
duke@435 226 }
duke@435 227
duke@435 228 size_t maxChunkSize() const;
duke@435 229 size_t totalChunkSize(debug_only(const Mutex* lock)) const {
duke@435 230 debug_only(
duke@435 231 if (lock != NULL && lock->owned_by_self()) {
duke@435 232 assert(totalSizeInTree(root()) == totalSize(),
duke@435 233 "_totalSize inconsistency");
duke@435 234 }
duke@435 235 )
duke@435 236 return totalSize();
duke@435 237 }
duke@435 238
duke@435 239 size_t minSize() const {
duke@435 240 return MIN_TREE_CHUNK_SIZE;
duke@435 241 }
duke@435 242
duke@435 243 double sum_of_squared_block_sizes() const {
duke@435 244 return sum_of_squared_block_sizes(root());
duke@435 245 }
duke@435 246
duke@435 247 FreeChunk* find_chunk_ends_at(HeapWord* target) const;
duke@435 248
duke@435 249 // Find the list with size "size" in the binary tree and update
duke@435 250 // the statistics in the list according to "split" (chunk was
duke@435 251 // split or coalesce) and "birth" (chunk was added or removed).
duke@435 252 void dictCensusUpdate(size_t size, bool split, bool birth);
duke@435 253 // Return true if the dictionary is overpopulated (more chunks of
duke@435 254 // this size than desired) for size "size".
duke@435 255 bool coalDictOverPopulated(size_t size);
duke@435 256 // Methods called at the beginning of a sweep to prepare the
duke@435 257 // statistics for the sweep.
duke@435 258 void beginSweepDictCensus(double coalSurplusPercent,
ysr@1580 259 float inter_sweep_current,
ysr@1580 260 float inter_sweep_estimate,
ysr@1580 261 float intra_sweep_estimate);
duke@435 262 // Methods called after the end of a sweep to modify the
duke@435 263 // statistics for the sweep.
duke@435 264 void endSweepDictCensus(double splitSurplusPercent);
duke@435 265 // Return the largest free chunk in the tree.
duke@435 266 FreeChunk* findLargestDict() const;
duke@435 267 // Accessors for statistics
duke@435 268 void setTreeSurplus(double splitSurplusPercent);
duke@435 269 void setTreeHints(void);
duke@435 270 // Reset statistics for all the lists in the tree.
duke@435 271 void clearTreeCensus(void);
duke@435 272 // Print the statistcis for all the lists in the tree. Also may
duke@435 273 // print out summaries.
duke@435 274 void printDictCensus(void) const;
ysr@1580 275 void print_free_lists(outputStream* st) const;
duke@435 276
duke@435 277 // For debugging. Returns the sum of the _returnedBytes for
duke@435 278 // all lists in the tree.
duke@435 279 size_t sumDictReturnedBytes() PRODUCT_RETURN0;
duke@435 280 // Sets the _returnedBytes for all the lists in the tree to zero.
duke@435 281 void initializeDictReturnedBytes() PRODUCT_RETURN;
duke@435 282 // For debugging. Return the total number of chunks in the dictionary.
duke@435 283 size_t totalCount() PRODUCT_RETURN0;
duke@435 284
duke@435 285 void reportStatistics() const;
duke@435 286
duke@435 287 void verify() const;
duke@435 288 };

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