Wed, 23 Sep 2009 23:56:15 -0700
Merge
duke@435 | 1 | /* |
xdono@631 | 2 | * Copyright 2001-2008 Sun Microsystems, Inc. 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 | * |
duke@435 | 19 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
duke@435 | 20 | * CA 95054 USA or visit www.sun.com if you need additional information or |
duke@435 | 21 | * have any questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
duke@435 | 25 | class CompactibleFreeListSpace; |
duke@435 | 26 | |
duke@435 | 27 | // A class for maintaining a free list of FreeChunk's. The FreeList |
duke@435 | 28 | // maintains a the structure of the list (head, tail, etc.) plus |
duke@435 | 29 | // statistics for allocations from the list. The links between items |
duke@435 | 30 | // are not part of FreeList. The statistics are |
duke@435 | 31 | // used to make decisions about coalescing FreeChunk's when they |
duke@435 | 32 | // are swept during collection. |
duke@435 | 33 | // |
duke@435 | 34 | // See the corresponding .cpp file for a description of the specifics |
duke@435 | 35 | // for that implementation. |
duke@435 | 36 | |
duke@435 | 37 | class Mutex; |
duke@435 | 38 | |
duke@435 | 39 | class FreeList VALUE_OBJ_CLASS_SPEC { |
duke@435 | 40 | friend class CompactibleFreeListSpace; |
dcubed@587 | 41 | friend class VMStructs; |
ysr@447 | 42 | friend class printTreeCensusClosure; |
duke@435 | 43 | FreeChunk* _head; // List of free chunks |
duke@435 | 44 | FreeChunk* _tail; // Tail of list of free chunks |
duke@435 | 45 | size_t _size; // Size in Heap words of each chunks |
duke@435 | 46 | ssize_t _count; // Number of entries in list |
duke@435 | 47 | size_t _hint; // next larger size list with a positive surplus |
duke@435 | 48 | |
duke@435 | 49 | AllocationStats _allocation_stats; // statistics for smart allocation |
duke@435 | 50 | |
duke@435 | 51 | #ifdef ASSERT |
duke@435 | 52 | Mutex* _protecting_lock; |
duke@435 | 53 | #endif |
duke@435 | 54 | |
duke@435 | 55 | // Asserts false if the protecting lock (if any) is not held. |
duke@435 | 56 | void assert_proper_lock_protection_work() const PRODUCT_RETURN; |
duke@435 | 57 | void assert_proper_lock_protection() const { |
duke@435 | 58 | #ifdef ASSERT |
duke@435 | 59 | if (_protecting_lock != NULL) |
duke@435 | 60 | assert_proper_lock_protection_work(); |
duke@435 | 61 | #endif |
duke@435 | 62 | } |
duke@435 | 63 | |
duke@435 | 64 | // Initialize the allocation statistics. |
duke@435 | 65 | protected: |
duke@435 | 66 | void init_statistics(); |
duke@435 | 67 | void set_count(ssize_t v) { _count = v;} |
ysr@447 | 68 | void increment_count() { _count++; } |
duke@435 | 69 | void decrement_count() { |
duke@435 | 70 | _count--; |
ysr@447 | 71 | assert(_count >= 0, "Count should not be negative"); |
ysr@447 | 72 | } |
duke@435 | 73 | |
duke@435 | 74 | public: |
duke@435 | 75 | // Constructor |
duke@435 | 76 | // Construct a list without any entries. |
duke@435 | 77 | FreeList(); |
duke@435 | 78 | // Construct a list with "fc" as the first (and lone) entry in the list. |
duke@435 | 79 | FreeList(FreeChunk* fc); |
duke@435 | 80 | // Construct a list which will have a FreeChunk at address "addr" and |
duke@435 | 81 | // of size "size" as the first (and lone) entry in the list. |
duke@435 | 82 | FreeList(HeapWord* addr, size_t size); |
duke@435 | 83 | |
duke@435 | 84 | // Reset the head, tail, hint, and count of a free list. |
duke@435 | 85 | void reset(size_t hint); |
duke@435 | 86 | |
duke@435 | 87 | // Declare the current free list to be protected by the given lock. |
duke@435 | 88 | #ifdef ASSERT |
duke@435 | 89 | void set_protecting_lock(Mutex* protecting_lock) { |
duke@435 | 90 | _protecting_lock = protecting_lock; |
duke@435 | 91 | } |
duke@435 | 92 | #endif |
duke@435 | 93 | |
duke@435 | 94 | // Accessors. |
duke@435 | 95 | FreeChunk* head() const { |
duke@435 | 96 | assert_proper_lock_protection(); |
duke@435 | 97 | return _head; |
duke@435 | 98 | } |
duke@435 | 99 | void set_head(FreeChunk* v) { |
duke@435 | 100 | assert_proper_lock_protection(); |
duke@435 | 101 | _head = v; |
duke@435 | 102 | assert(!_head || _head->size() == _size, "bad chunk size"); |
duke@435 | 103 | } |
duke@435 | 104 | // Set the head of the list and set the prev field of non-null |
duke@435 | 105 | // values to NULL. |
duke@435 | 106 | void link_head(FreeChunk* v) { |
duke@435 | 107 | assert_proper_lock_protection(); |
duke@435 | 108 | set_head(v); |
duke@435 | 109 | // If this method is not used (just set the head instead), |
duke@435 | 110 | // this check can be avoided. |
duke@435 | 111 | if (v != NULL) { |
duke@435 | 112 | v->linkPrev(NULL); |
duke@435 | 113 | } |
duke@435 | 114 | } |
duke@435 | 115 | |
duke@435 | 116 | FreeChunk* tail() const { |
duke@435 | 117 | assert_proper_lock_protection(); |
duke@435 | 118 | return _tail; |
duke@435 | 119 | } |
duke@435 | 120 | void set_tail(FreeChunk* v) { |
duke@435 | 121 | assert_proper_lock_protection(); |
duke@435 | 122 | _tail = v; |
duke@435 | 123 | assert(!_tail || _tail->size() == _size, "bad chunk size"); |
duke@435 | 124 | } |
duke@435 | 125 | // Set the tail of the list and set the next field of non-null |
duke@435 | 126 | // values to NULL. |
duke@435 | 127 | void link_tail(FreeChunk* v) { |
duke@435 | 128 | assert_proper_lock_protection(); |
duke@435 | 129 | set_tail(v); |
duke@435 | 130 | if (v != NULL) { |
duke@435 | 131 | v->clearNext(); |
duke@435 | 132 | } |
duke@435 | 133 | } |
duke@435 | 134 | |
duke@435 | 135 | // No locking checks in read-accessors: lock-free reads (only) are benign. |
duke@435 | 136 | // Readers are expected to have the lock if they are doing work that |
duke@435 | 137 | // requires atomicity guarantees in sections of code. |
duke@435 | 138 | size_t size() const { |
duke@435 | 139 | return _size; |
duke@435 | 140 | } |
duke@435 | 141 | void set_size(size_t v) { |
duke@435 | 142 | assert_proper_lock_protection(); |
duke@435 | 143 | _size = v; |
duke@435 | 144 | } |
duke@435 | 145 | ssize_t count() const { |
duke@435 | 146 | return _count; |
duke@435 | 147 | } |
duke@435 | 148 | size_t hint() const { |
duke@435 | 149 | return _hint; |
duke@435 | 150 | } |
duke@435 | 151 | void set_hint(size_t v) { |
duke@435 | 152 | assert_proper_lock_protection(); |
duke@435 | 153 | assert(v == 0 || _size < v, "Bad hint"); _hint = v; |
duke@435 | 154 | } |
duke@435 | 155 | |
duke@435 | 156 | // Accessors for statistics |
duke@435 | 157 | AllocationStats* allocation_stats() { |
duke@435 | 158 | assert_proper_lock_protection(); |
duke@435 | 159 | return &_allocation_stats; |
duke@435 | 160 | } |
duke@435 | 161 | |
duke@435 | 162 | ssize_t desired() const { |
duke@435 | 163 | return _allocation_stats.desired(); |
duke@435 | 164 | } |
ysr@447 | 165 | void set_desired(ssize_t v) { |
ysr@447 | 166 | assert_proper_lock_protection(); |
ysr@447 | 167 | _allocation_stats.set_desired(v); |
ysr@447 | 168 | } |
duke@435 | 169 | void compute_desired(float inter_sweep_current, |
duke@435 | 170 | float inter_sweep_estimate) { |
duke@435 | 171 | assert_proper_lock_protection(); |
duke@435 | 172 | _allocation_stats.compute_desired(_count, |
duke@435 | 173 | inter_sweep_current, |
duke@435 | 174 | inter_sweep_estimate); |
duke@435 | 175 | } |
duke@435 | 176 | ssize_t coalDesired() const { |
duke@435 | 177 | return _allocation_stats.coalDesired(); |
duke@435 | 178 | } |
duke@435 | 179 | void set_coalDesired(ssize_t v) { |
duke@435 | 180 | assert_proper_lock_protection(); |
duke@435 | 181 | _allocation_stats.set_coalDesired(v); |
duke@435 | 182 | } |
duke@435 | 183 | |
duke@435 | 184 | ssize_t surplus() const { |
duke@435 | 185 | return _allocation_stats.surplus(); |
duke@435 | 186 | } |
duke@435 | 187 | void set_surplus(ssize_t v) { |
duke@435 | 188 | assert_proper_lock_protection(); |
duke@435 | 189 | _allocation_stats.set_surplus(v); |
duke@435 | 190 | } |
duke@435 | 191 | void increment_surplus() { |
duke@435 | 192 | assert_proper_lock_protection(); |
duke@435 | 193 | _allocation_stats.increment_surplus(); |
duke@435 | 194 | } |
duke@435 | 195 | void decrement_surplus() { |
duke@435 | 196 | assert_proper_lock_protection(); |
duke@435 | 197 | _allocation_stats.decrement_surplus(); |
duke@435 | 198 | } |
duke@435 | 199 | |
duke@435 | 200 | ssize_t bfrSurp() const { |
duke@435 | 201 | return _allocation_stats.bfrSurp(); |
duke@435 | 202 | } |
duke@435 | 203 | void set_bfrSurp(ssize_t v) { |
duke@435 | 204 | assert_proper_lock_protection(); |
duke@435 | 205 | _allocation_stats.set_bfrSurp(v); |
duke@435 | 206 | } |
duke@435 | 207 | ssize_t prevSweep() const { |
duke@435 | 208 | return _allocation_stats.prevSweep(); |
duke@435 | 209 | } |
duke@435 | 210 | void set_prevSweep(ssize_t v) { |
duke@435 | 211 | assert_proper_lock_protection(); |
duke@435 | 212 | _allocation_stats.set_prevSweep(v); |
duke@435 | 213 | } |
duke@435 | 214 | ssize_t beforeSweep() const { |
duke@435 | 215 | return _allocation_stats.beforeSweep(); |
duke@435 | 216 | } |
duke@435 | 217 | void set_beforeSweep(ssize_t v) { |
duke@435 | 218 | assert_proper_lock_protection(); |
duke@435 | 219 | _allocation_stats.set_beforeSweep(v); |
duke@435 | 220 | } |
duke@435 | 221 | |
duke@435 | 222 | ssize_t coalBirths() const { |
duke@435 | 223 | return _allocation_stats.coalBirths(); |
duke@435 | 224 | } |
duke@435 | 225 | void set_coalBirths(ssize_t v) { |
duke@435 | 226 | assert_proper_lock_protection(); |
duke@435 | 227 | _allocation_stats.set_coalBirths(v); |
duke@435 | 228 | } |
duke@435 | 229 | void increment_coalBirths() { |
duke@435 | 230 | assert_proper_lock_protection(); |
duke@435 | 231 | _allocation_stats.increment_coalBirths(); |
duke@435 | 232 | } |
duke@435 | 233 | |
duke@435 | 234 | ssize_t coalDeaths() const { |
duke@435 | 235 | return _allocation_stats.coalDeaths(); |
duke@435 | 236 | } |
duke@435 | 237 | void set_coalDeaths(ssize_t v) { |
duke@435 | 238 | assert_proper_lock_protection(); |
duke@435 | 239 | _allocation_stats.set_coalDeaths(v); |
duke@435 | 240 | } |
duke@435 | 241 | void increment_coalDeaths() { |
duke@435 | 242 | assert_proper_lock_protection(); |
duke@435 | 243 | _allocation_stats.increment_coalDeaths(); |
duke@435 | 244 | } |
duke@435 | 245 | |
duke@435 | 246 | ssize_t splitBirths() const { |
duke@435 | 247 | return _allocation_stats.splitBirths(); |
duke@435 | 248 | } |
duke@435 | 249 | void set_splitBirths(ssize_t v) { |
duke@435 | 250 | assert_proper_lock_protection(); |
duke@435 | 251 | _allocation_stats.set_splitBirths(v); |
duke@435 | 252 | } |
duke@435 | 253 | void increment_splitBirths() { |
duke@435 | 254 | assert_proper_lock_protection(); |
duke@435 | 255 | _allocation_stats.increment_splitBirths(); |
duke@435 | 256 | } |
duke@435 | 257 | |
duke@435 | 258 | ssize_t splitDeaths() const { |
duke@435 | 259 | return _allocation_stats.splitDeaths(); |
duke@435 | 260 | } |
duke@435 | 261 | void set_splitDeaths(ssize_t v) { |
duke@435 | 262 | assert_proper_lock_protection(); |
duke@435 | 263 | _allocation_stats.set_splitDeaths(v); |
duke@435 | 264 | } |
duke@435 | 265 | void increment_splitDeaths() { |
duke@435 | 266 | assert_proper_lock_protection(); |
duke@435 | 267 | _allocation_stats.increment_splitDeaths(); |
duke@435 | 268 | } |
duke@435 | 269 | |
duke@435 | 270 | NOT_PRODUCT( |
duke@435 | 271 | // For debugging. The "_returnedBytes" in all the lists are summed |
duke@435 | 272 | // and compared with the total number of bytes swept during a |
duke@435 | 273 | // collection. |
duke@435 | 274 | size_t returnedBytes() const { return _allocation_stats.returnedBytes(); } |
duke@435 | 275 | void set_returnedBytes(size_t v) { _allocation_stats.set_returnedBytes(v); } |
duke@435 | 276 | void increment_returnedBytes_by(size_t v) { |
duke@435 | 277 | _allocation_stats.set_returnedBytes(_allocation_stats.returnedBytes() + v); |
duke@435 | 278 | } |
duke@435 | 279 | ) |
duke@435 | 280 | |
duke@435 | 281 | // Unlink head of list and return it. Returns NULL if |
duke@435 | 282 | // the list is empty. |
duke@435 | 283 | FreeChunk* getChunkAtHead(); |
duke@435 | 284 | |
duke@435 | 285 | // Remove the first "n" or "count", whichever is smaller, chunks from the |
duke@435 | 286 | // list, setting "fl", which is required to be empty, to point to them. |
duke@435 | 287 | void getFirstNChunksFromList(size_t n, FreeList* fl); |
duke@435 | 288 | |
duke@435 | 289 | // Unlink this chunk from it's free list |
duke@435 | 290 | void removeChunk(FreeChunk* fc); |
duke@435 | 291 | |
duke@435 | 292 | // Add this chunk to this free list. |
duke@435 | 293 | void returnChunkAtHead(FreeChunk* fc); |
duke@435 | 294 | void returnChunkAtTail(FreeChunk* fc); |
duke@435 | 295 | |
duke@435 | 296 | // Similar to returnChunk* but also records some diagnostic |
duke@435 | 297 | // information. |
duke@435 | 298 | void returnChunkAtHead(FreeChunk* fc, bool record_return); |
duke@435 | 299 | void returnChunkAtTail(FreeChunk* fc, bool record_return); |
duke@435 | 300 | |
duke@435 | 301 | // Prepend "fl" (whose size is required to be the same as that of "this") |
duke@435 | 302 | // to the front of "this" list. |
duke@435 | 303 | void prepend(FreeList* fl); |
duke@435 | 304 | |
duke@435 | 305 | // Verify that the chunk is in the list. |
duke@435 | 306 | // found. Return NULL if "fc" is not found. |
duke@435 | 307 | bool verifyChunkInFreeLists(FreeChunk* fc) const; |
ysr@447 | 308 | |
ysr@447 | 309 | // Printing support |
ysr@447 | 310 | static void print_labels_on(outputStream* st, const char* c); |
ysr@447 | 311 | void print_on(outputStream* st, const char* c = NULL) const; |
duke@435 | 312 | }; |