Mercurial > hg > truffle
annotate src/share/vm/memory/blockOffsetTable.cpp @ 6197:d2a62e0f25eb
6995781: Native Memory Tracking (Phase 1)
7151532: DCmd for hotspot native memory tracking
Summary: Implementation of native memory tracking phase 1, which tracks VM native memory usage, and related DCmd
Reviewed-by: acorn, coleenp, fparain
| author | zgu |
|---|---|
| date | Thu, 28 Jun 2012 17:03:16 -0400 |
| parents | 537a4053b0f9 |
| children | da91efe96a93 |
| rev | line source |
|---|---|
| 0 | 1 /* |
|
3746
537a4053b0f9
7042740: CMS: assert(n> q) failed: Looping at: ... blockOffsetTable.cpp:557
ysr
parents:
3359
diff
changeset
|
2 * Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved. |
| 0 | 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 * | |
| 5 * This code is free software; you can redistribute it and/or modify it | |
| 6 * under the terms of the GNU General Public License version 2 only, as | |
| 7 * published by the Free Software Foundation. | |
| 8 * | |
| 9 * This code is distributed in the hope that it will be useful, but WITHOUT | |
| 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| 12 * version 2 for more details (a copy is included in the LICENSE file that | |
| 13 * accompanied this code). | |
| 14 * | |
| 15 * You should have received a copy of the GNU General Public License version | |
| 16 * 2 along with this work; if not, write to the Free Software Foundation, | |
| 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | |
| 18 * | |
|
1552
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
1489
diff
changeset
|
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
|
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
1489
diff
changeset
|
20 * or visit www.oracle.com if you need additional information or have any |
|
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
1489
diff
changeset
|
21 * questions. |
| 0 | 22 * |
| 23 */ | |
| 24 | |
| 1972 | 25 #include "precompiled.hpp" |
| 26 #include "gc_interface/collectedHeap.inline.hpp" | |
| 27 #include "memory/blockOffsetTable.inline.hpp" | |
| 28 #include "memory/iterator.hpp" | |
| 29 #include "memory/space.inline.hpp" | |
| 30 #include "memory/universe.hpp" | |
| 31 #include "oops/oop.inline.hpp" | |
| 32 #include "runtime/java.hpp" | |
| 6197 | 33 #include "services/memTracker.hpp" |
| 0 | 34 |
| 35 ////////////////////////////////////////////////////////////////////// | |
| 36 // BlockOffsetSharedArray | |
| 37 ////////////////////////////////////////////////////////////////////// | |
| 38 | |
| 39 BlockOffsetSharedArray::BlockOffsetSharedArray(MemRegion reserved, | |
| 40 size_t init_word_size): | |
| 41 _reserved(reserved), _end(NULL) | |
| 42 { | |
| 43 size_t size = compute_size(reserved.word_size()); | |
| 44 ReservedSpace rs(size); | |
| 45 if (!rs.is_reserved()) { | |
| 46 vm_exit_during_initialization("Could not reserve enough space for heap offset array"); | |
| 47 } | |
| 6197 | 48 |
| 49 MemTracker::record_virtual_memory_type((address)rs.base(), mtGC); | |
| 50 | |
| 0 | 51 if (!_vs.initialize(rs, 0)) { |
| 52 vm_exit_during_initialization("Could not reserve enough space for heap offset array"); | |
| 53 } | |
| 54 _offset_array = (u_char*)_vs.low_boundary(); | |
| 55 resize(init_word_size); | |
| 56 if (TraceBlockOffsetTable) { | |
| 57 gclog_or_tty->print_cr("BlockOffsetSharedArray::BlockOffsetSharedArray: "); | |
| 58 gclog_or_tty->print_cr(" " | |
| 59 " rs.base(): " INTPTR_FORMAT | |
| 60 " rs.size(): " INTPTR_FORMAT | |
| 61 " rs end(): " INTPTR_FORMAT, | |
| 62 rs.base(), rs.size(), rs.base() + rs.size()); | |
| 63 gclog_or_tty->print_cr(" " | |
| 64 " _vs.low_boundary(): " INTPTR_FORMAT | |
| 65 " _vs.high_boundary(): " INTPTR_FORMAT, | |
| 66 _vs.low_boundary(), | |
| 67 _vs.high_boundary()); | |
| 68 } | |
| 69 } | |
| 70 | |
| 71 void BlockOffsetSharedArray::resize(size_t new_word_size) { | |
| 72 assert(new_word_size <= _reserved.word_size(), "Resize larger than reserved"); | |
| 73 size_t new_size = compute_size(new_word_size); | |
| 74 size_t old_size = _vs.committed_size(); | |
| 75 size_t delta; | |
| 76 char* high = _vs.high(); | |
| 77 _end = _reserved.start() + new_word_size; | |
| 78 if (new_size > old_size) { | |
| 79 delta = ReservedSpace::page_align_size_up(new_size - old_size); | |
| 80 assert(delta > 0, "just checking"); | |
| 81 if (!_vs.expand_by(delta)) { | |
| 82 // Do better than this for Merlin | |
| 83 vm_exit_out_of_memory(delta, "offset table expansion"); | |
| 84 } | |
| 85 assert(_vs.high() == high + delta, "invalid expansion"); | |
| 86 } else { | |
| 87 delta = ReservedSpace::page_align_size_down(old_size - new_size); | |
| 88 if (delta == 0) return; | |
| 89 _vs.shrink_by(delta); | |
| 90 assert(_vs.high() == high - delta, "invalid expansion"); | |
| 91 } | |
| 92 } | |
| 93 | |
| 94 bool BlockOffsetSharedArray::is_card_boundary(HeapWord* p) const { | |
| 95 assert(p >= _reserved.start(), "just checking"); | |
| 96 size_t delta = pointer_delta(p, _reserved.start()); | |
| 97 return (delta & right_n_bits(LogN_words)) == (size_t)NoBits; | |
| 98 } | |
| 99 | |
| 100 | |
| 101 void BlockOffsetSharedArray::serialize(SerializeOopClosure* soc, | |
| 102 HeapWord* start, HeapWord* end) { | |
| 103 assert(_offset_array[0] == 0, "objects can't cross covered areas"); | |
| 104 assert(start <= end, "bad address range"); | |
| 105 size_t start_index = index_for(start); | |
| 106 size_t end_index = index_for(end-1)+1; | |
| 107 soc->do_region(&_offset_array[start_index], | |
| 108 (end_index - start_index) * sizeof(_offset_array[0])); | |
| 109 } | |
| 110 | |
| 111 ////////////////////////////////////////////////////////////////////// | |
| 112 // BlockOffsetArray | |
| 113 ////////////////////////////////////////////////////////////////////// | |
| 114 | |
| 115 BlockOffsetArray::BlockOffsetArray(BlockOffsetSharedArray* array, | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
116 MemRegion mr, bool init_to_zero_) : |
| 0 | 117 BlockOffsetTable(mr.start(), mr.end()), |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
118 _array(array) |
| 0 | 119 { |
| 120 assert(_bottom <= _end, "arguments out of order"); | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
121 set_init_to_zero(init_to_zero_); |
|
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
122 if (!init_to_zero_) { |
| 0 | 123 // initialize cards to point back to mr.start() |
| 124 set_remainder_to_point_to_start(mr.start() + N_words, mr.end()); | |
| 125 _array->set_offset_array(0, 0); // set first card to 0 | |
| 126 } | |
| 127 } | |
| 128 | |
| 129 | |
| 130 // The arguments follow the normal convention of denoting | |
| 131 // a right-open interval: [start, end) | |
| 132 void | |
| 133 BlockOffsetArray:: | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
134 set_remainder_to_point_to_start(HeapWord* start, HeapWord* end, bool reducing) { |
| 0 | 135 |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
136 check_reducing_assertion(reducing); |
| 0 | 137 if (start >= end) { |
| 138 // The start address is equal to the end address (or to | |
| 139 // the right of the end address) so there are not cards | |
| 140 // that need to be updated.. | |
| 141 return; | |
| 142 } | |
| 143 | |
| 144 // Write the backskip value for each region. | |
| 145 // | |
| 146 // offset | |
| 147 // card 2nd 3rd | |
| 148 // | +- 1st | | | |
| 149 // v v v v | |
| 150 // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+- | |
| 151 // |x|0|0|0|0|0|0|0|1|1|1|1|1|1| ... |1|1|1|1|2|2|2|2|2|2| ... | |
| 152 // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+- | |
| 153 // 11 19 75 | |
| 154 // 12 | |
| 155 // | |
| 156 // offset card is the card that points to the start of an object | |
| 157 // x - offset value of offset card | |
| 158 // 1st - start of first logarithmic region | |
| 159 // 0 corresponds to logarithmic value N_words + 0 and 2**(3 * 0) = 1 | |
| 160 // 2nd - start of second logarithmic region | |
| 161 // 1 corresponds to logarithmic value N_words + 1 and 2**(3 * 1) = 8 | |
| 162 // 3rd - start of third logarithmic region | |
| 163 // 2 corresponds to logarithmic value N_words + 2 and 2**(3 * 2) = 64 | |
| 164 // | |
| 165 // integer below the block offset entry is an example of | |
| 166 // the index of the entry | |
| 167 // | |
| 168 // Given an address, | |
| 169 // Find the index for the address | |
| 170 // Find the block offset table entry | |
| 171 // Convert the entry to a back slide | |
| 172 // (e.g., with today's, offset = 0x81 => | |
| 173 // back slip = 2**(3*(0x81 - N_words)) = 2**3) = 8 | |
| 174 // Move back N (e.g., 8) entries and repeat with the | |
| 175 // value of the new entry | |
| 176 // | |
| 177 size_t start_card = _array->index_for(start); | |
| 178 size_t end_card = _array->index_for(end-1); | |
| 179 assert(start ==_array->address_for_index(start_card), "Precondition"); | |
| 180 assert(end ==_array->address_for_index(end_card)+N_words, "Precondition"); | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
181 set_remainder_to_point_to_start_incl(start_card, end_card, reducing); // closed interval |
| 0 | 182 } |
| 183 | |
| 184 | |
| 185 // Unlike the normal convention in this code, the argument here denotes | |
| 186 // a closed, inclusive interval: [start_card, end_card], cf set_remainder_to_point_to_start() | |
| 187 // above. | |
| 188 void | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
189 BlockOffsetArray::set_remainder_to_point_to_start_incl(size_t start_card, size_t end_card, bool reducing) { |
|
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
190 |
|
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
191 check_reducing_assertion(reducing); |
| 0 | 192 if (start_card > end_card) { |
| 193 return; | |
| 194 } | |
| 195 assert(start_card > _array->index_for(_bottom), "Cannot be first card"); | |
| 196 assert(_array->offset_array(start_card-1) <= N_words, | |
| 197 "Offset card has an unexpected value"); | |
| 198 size_t start_card_for_region = start_card; | |
| 199 u_char offset = max_jubyte; | |
| 342 | 200 for (int i = 0; i < N_powers; i++) { |
| 0 | 201 // -1 so that the the card with the actual offset is counted. Another -1 |
| 202 // so that the reach ends in this region and not at the start | |
| 203 // of the next. | |
| 204 size_t reach = start_card - 1 + (power_to_cards_back(i+1) - 1); | |
| 205 offset = N_words + i; | |
| 206 if (reach >= end_card) { | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
207 _array->set_offset_array(start_card_for_region, end_card, offset, reducing); |
| 0 | 208 start_card_for_region = reach + 1; |
| 209 break; | |
| 210 } | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
211 _array->set_offset_array(start_card_for_region, reach, offset, reducing); |
| 0 | 212 start_card_for_region = reach + 1; |
| 213 } | |
| 214 assert(start_card_for_region > end_card, "Sanity check"); | |
| 215 DEBUG_ONLY(check_all_cards(start_card, end_card);) | |
| 216 } | |
| 217 | |
| 218 // The card-interval [start_card, end_card] is a closed interval; this | |
| 219 // is an expensive check -- use with care and only under protection of | |
| 220 // suitable flag. | |
| 221 void BlockOffsetArray::check_all_cards(size_t start_card, size_t end_card) const { | |
| 222 | |
| 223 if (end_card < start_card) { | |
| 224 return; | |
| 225 } | |
| 226 guarantee(_array->offset_array(start_card) == N_words, "Wrong value in second card"); | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
227 u_char last_entry = N_words; |
| 0 | 228 for (size_t c = start_card + 1; c <= end_card; c++ /* yeah! */) { |
| 229 u_char entry = _array->offset_array(c); | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
230 guarantee(entry >= last_entry, "Monotonicity"); |
| 0 | 231 if (c - start_card > power_to_cards_back(1)) { |
| 232 guarantee(entry > N_words, "Should be in logarithmic region"); | |
| 233 } | |
| 234 size_t backskip = entry_to_cards_back(entry); | |
| 235 size_t landing_card = c - backskip; | |
| 236 guarantee(landing_card >= (start_card - 1), "Inv"); | |
| 237 if (landing_card >= start_card) { | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
238 guarantee(_array->offset_array(landing_card) <= entry, "Monotonicity"); |
| 0 | 239 } else { |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
240 guarantee(landing_card == (start_card - 1), "Tautology"); |
|
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
241 // Note that N_words is the maximum offset value |
| 0 | 242 guarantee(_array->offset_array(landing_card) <= N_words, "Offset value"); |
| 243 } | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
244 last_entry = entry; // remember for monotonicity test |
| 0 | 245 } |
| 246 } | |
| 247 | |
| 248 | |
| 249 void | |
| 250 BlockOffsetArray::alloc_block(HeapWord* blk_start, HeapWord* blk_end) { | |
| 251 assert(blk_start != NULL && blk_end > blk_start, | |
| 252 "phantom block"); | |
| 253 single_block(blk_start, blk_end); | |
| 254 } | |
| 255 | |
| 256 // Action_mark - update the BOT for the block [blk_start, blk_end). | |
| 257 // Current typical use is for splitting a block. | |
| 258 // Action_single - udpate the BOT for an allocation. | |
| 259 // Action_verify - BOT verification. | |
| 260 void | |
| 261 BlockOffsetArray::do_block_internal(HeapWord* blk_start, | |
| 262 HeapWord* blk_end, | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
263 Action action, bool reducing) { |
| 0 | 264 assert(Universe::heap()->is_in_reserved(blk_start), |
| 265 "reference must be into the heap"); | |
| 266 assert(Universe::heap()->is_in_reserved(blk_end-1), | |
| 267 "limit must be within the heap"); | |
| 268 // This is optimized to make the test fast, assuming we only rarely | |
| 269 // cross boundaries. | |
| 270 uintptr_t end_ui = (uintptr_t)(blk_end - 1); | |
| 271 uintptr_t start_ui = (uintptr_t)blk_start; | |
| 272 // Calculate the last card boundary preceding end of blk | |
| 273 intptr_t boundary_before_end = (intptr_t)end_ui; | |
| 274 clear_bits(boundary_before_end, right_n_bits(LogN)); | |
| 275 if (start_ui <= (uintptr_t)boundary_before_end) { | |
| 276 // blk starts at or crosses a boundary | |
| 277 // Calculate index of card on which blk begins | |
| 278 size_t start_index = _array->index_for(blk_start); | |
| 279 // Index of card on which blk ends | |
| 280 size_t end_index = _array->index_for(blk_end - 1); | |
| 281 // Start address of card on which blk begins | |
| 282 HeapWord* boundary = _array->address_for_index(start_index); | |
| 283 assert(boundary <= blk_start, "blk should start at or after boundary"); | |
| 284 if (blk_start != boundary) { | |
| 285 // blk starts strictly after boundary | |
| 286 // adjust card boundary and start_index forward to next card | |
| 287 boundary += N_words; | |
| 288 start_index++; | |
| 289 } | |
| 290 assert(start_index <= end_index, "monotonicity of index_for()"); | |
| 291 assert(boundary <= (HeapWord*)boundary_before_end, "tautology"); | |
| 292 switch (action) { | |
| 293 case Action_mark: { | |
| 294 if (init_to_zero()) { | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
295 _array->set_offset_array(start_index, boundary, blk_start, reducing); |
| 0 | 296 break; |
| 297 } // Else fall through to the next case | |
| 298 } | |
| 299 case Action_single: { | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
300 _array->set_offset_array(start_index, boundary, blk_start, reducing); |
| 0 | 301 // We have finished marking the "offset card". We need to now |
| 302 // mark the subsequent cards that this blk spans. | |
| 303 if (start_index < end_index) { | |
| 304 HeapWord* rem_st = _array->address_for_index(start_index) + N_words; | |
| 305 HeapWord* rem_end = _array->address_for_index(end_index) + N_words; | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
306 set_remainder_to_point_to_start(rem_st, rem_end, reducing); |
| 0 | 307 } |
| 308 break; | |
| 309 } | |
| 310 case Action_check: { | |
| 311 _array->check_offset_array(start_index, boundary, blk_start); | |
| 312 // We have finished checking the "offset card". We need to now | |
| 313 // check the subsequent cards that this blk spans. | |
| 314 check_all_cards(start_index + 1, end_index); | |
| 315 break; | |
| 316 } | |
| 317 default: | |
| 318 ShouldNotReachHere(); | |
| 319 } | |
| 320 } | |
| 321 } | |
| 322 | |
| 323 // The range [blk_start, blk_end) represents a single contiguous block | |
| 324 // of storage; modify the block offset table to represent this | |
| 325 // information; Right-open interval: [blk_start, blk_end) | |
| 326 // NOTE: this method does _not_ adjust _unallocated_block. | |
| 327 void | |
| 328 BlockOffsetArray::single_block(HeapWord* blk_start, | |
| 329 HeapWord* blk_end) { | |
| 330 do_block_internal(blk_start, blk_end, Action_single); | |
| 331 } | |
| 332 | |
| 333 void BlockOffsetArray::verify() const { | |
| 334 // For each entry in the block offset table, verify that | |
| 335 // the entry correctly finds the start of an object at the | |
| 336 // first address covered by the block or to the left of that | |
| 337 // first address. | |
| 338 | |
| 339 size_t next_index = 1; | |
| 340 size_t last_index = last_active_index(); | |
| 341 | |
| 342 // Use for debugging. Initialize to NULL to distinguish the | |
| 343 // first iteration through the while loop. | |
| 344 HeapWord* last_p = NULL; | |
| 345 HeapWord* last_start = NULL; | |
| 346 oop last_o = NULL; | |
| 347 | |
| 348 while (next_index <= last_index) { | |
| 349 // Use an address past the start of the address for | |
| 350 // the entry. | |
| 351 HeapWord* p = _array->address_for_index(next_index) + 1; | |
| 352 if (p >= _end) { | |
| 353 // That's all of the allocated block table. | |
| 354 return; | |
| 355 } | |
| 356 // block_start() asserts that start <= p. | |
| 357 HeapWord* start = block_start(p); | |
| 358 // First check if the start is an allocated block and only | |
| 359 // then if it is a valid object. | |
| 360 oop o = oop(start); | |
| 361 assert(!Universe::is_fully_initialized() || | |
| 362 _sp->is_free_block(start) || | |
| 363 o->is_oop_or_null(), "Bad object was found"); | |
| 364 next_index++; | |
| 365 last_p = p; | |
| 366 last_start = start; | |
| 367 last_o = o; | |
| 368 } | |
| 369 } | |
| 370 | |
| 371 ////////////////////////////////////////////////////////////////////// | |
| 372 // BlockOffsetArrayNonContigSpace | |
| 373 ////////////////////////////////////////////////////////////////////// | |
| 374 | |
| 375 // The block [blk_start, blk_end) has been allocated; | |
| 376 // adjust the block offset table to represent this information; | |
| 377 // NOTE: Clients of BlockOffsetArrayNonContigSpace: consider using | |
| 378 // the somewhat more lightweight split_block() or | |
| 379 // (when init_to_zero()) mark_block() wherever possible. | |
| 380 // right-open interval: [blk_start, blk_end) | |
| 381 void | |
| 382 BlockOffsetArrayNonContigSpace::alloc_block(HeapWord* blk_start, | |
| 383 HeapWord* blk_end) { | |
| 384 assert(blk_start != NULL && blk_end > blk_start, | |
| 385 "phantom block"); | |
| 386 single_block(blk_start, blk_end); | |
| 387 allocated(blk_start, blk_end); | |
| 388 } | |
| 389 | |
| 390 // Adjust BOT to show that a previously whole block has been split | |
| 391 // into two. We verify the BOT for the first part (prefix) and | |
| 392 // update the BOT for the second part (suffix). | |
| 393 // blk is the start of the block | |
| 394 // blk_size is the size of the original block | |
| 395 // left_blk_size is the size of the first part of the split | |
| 396 void BlockOffsetArrayNonContigSpace::split_block(HeapWord* blk, | |
| 397 size_t blk_size, | |
| 398 size_t left_blk_size) { | |
| 399 // Verify that the BOT shows [blk, blk + blk_size) to be one block. | |
| 400 verify_single_block(blk, blk_size); | |
| 401 // Update the BOT to indicate that [blk + left_blk_size, blk + blk_size) | |
| 402 // is one single block. | |
| 403 assert(blk_size > 0, "Should be positive"); | |
| 404 assert(left_blk_size > 0, "Should be positive"); | |
| 405 assert(left_blk_size < blk_size, "Not a split"); | |
| 406 | |
| 407 // Start addresses of prefix block and suffix block. | |
| 408 HeapWord* pref_addr = blk; | |
| 409 HeapWord* suff_addr = blk + left_blk_size; | |
| 410 HeapWord* end_addr = blk + blk_size; | |
| 411 | |
| 412 // Indices for starts of prefix block and suffix block. | |
| 413 size_t pref_index = _array->index_for(pref_addr); | |
| 414 if (_array->address_for_index(pref_index) != pref_addr) { | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
415 // pref_addr does not begin pref_index |
| 0 | 416 pref_index++; |
| 417 } | |
| 418 | |
| 419 size_t suff_index = _array->index_for(suff_addr); | |
| 420 if (_array->address_for_index(suff_index) != suff_addr) { | |
| 421 // suff_addr does not begin suff_index | |
| 422 suff_index++; | |
| 423 } | |
| 424 | |
| 425 // Definition: A block B, denoted [B_start, B_end) __starts__ | |
| 426 // a card C, denoted [C_start, C_end), where C_start and C_end | |
| 427 // are the heap addresses that card C covers, iff | |
| 428 // B_start <= C_start < B_end. | |
| 429 // | |
| 430 // We say that a card C "is started by" a block B, iff | |
| 431 // B "starts" C. | |
| 432 // | |
| 433 // Note that the cardinality of the set of cards {C} | |
| 434 // started by a block B can be 0, 1, or more. | |
| 435 // | |
| 436 // Below, pref_index and suff_index are, respectively, the | |
| 437 // first (least) card indices that the prefix and suffix of | |
| 438 // the split start; end_index is one more than the index of | |
| 439 // the last (greatest) card that blk starts. | |
| 440 size_t end_index = _array->index_for(end_addr - 1) + 1; | |
| 441 | |
| 442 // Calculate the # cards that the prefix and suffix affect. | |
| 443 size_t num_pref_cards = suff_index - pref_index; | |
| 444 | |
| 445 size_t num_suff_cards = end_index - suff_index; | |
| 446 // Change the cards that need changing | |
| 447 if (num_suff_cards > 0) { | |
| 448 HeapWord* boundary = _array->address_for_index(suff_index); | |
| 449 // Set the offset card for suffix block | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
450 _array->set_offset_array(suff_index, boundary, suff_addr, true /* reducing */); |
| 0 | 451 // Change any further cards that need changing in the suffix |
| 452 if (num_pref_cards > 0) { | |
| 453 if (num_pref_cards >= num_suff_cards) { | |
| 454 // Unilaterally fix all of the suffix cards: closed card | |
| 455 // index interval in args below. | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
456 set_remainder_to_point_to_start_incl(suff_index + 1, end_index - 1, true /* reducing */); |
| 0 | 457 } else { |
| 458 // Unilaterally fix the first (num_pref_cards - 1) following | |
| 459 // the "offset card" in the suffix block. | |
| 460 set_remainder_to_point_to_start_incl(suff_index + 1, | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
461 suff_index + num_pref_cards - 1, true /* reducing */); |
| 0 | 462 // Fix the appropriate cards in the remainder of the |
| 463 // suffix block -- these are the last num_pref_cards | |
| 464 // cards in each power block of the "new" range plumbed | |
| 465 // from suff_addr. | |
| 466 bool more = true; | |
| 467 uint i = 1; | |
| 468 while (more && (i < N_powers)) { | |
| 469 size_t back_by = power_to_cards_back(i); | |
| 470 size_t right_index = suff_index + back_by - 1; | |
| 471 size_t left_index = right_index - num_pref_cards + 1; | |
| 472 if (right_index >= end_index - 1) { // last iteration | |
| 473 right_index = end_index - 1; | |
| 474 more = false; | |
| 475 } | |
| 476 if (back_by > num_pref_cards) { | |
| 477 // Fill in the remainder of this "power block", if it | |
| 478 // is non-null. | |
| 479 if (left_index <= right_index) { | |
| 480 _array->set_offset_array(left_index, right_index, | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
481 N_words + i - 1, true /* reducing */); |
| 0 | 482 } else { |
| 483 more = false; // we are done | |
| 484 } | |
| 485 i++; | |
| 486 break; | |
| 487 } | |
| 488 i++; | |
| 489 } | |
| 490 while (more && (i < N_powers)) { | |
| 491 size_t back_by = power_to_cards_back(i); | |
| 492 size_t right_index = suff_index + back_by - 1; | |
| 493 size_t left_index = right_index - num_pref_cards + 1; | |
| 494 if (right_index >= end_index - 1) { // last iteration | |
| 495 right_index = end_index - 1; | |
| 496 if (left_index > right_index) { | |
| 497 break; | |
| 498 } | |
| 499 more = false; | |
| 500 } | |
| 501 assert(left_index <= right_index, "Error"); | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
502 _array->set_offset_array(left_index, right_index, N_words + i - 1, true /* reducing */); |
| 0 | 503 i++; |
| 504 } | |
| 505 } | |
| 506 } // else no more cards to fix in suffix | |
| 507 } // else nothing needs to be done | |
| 508 // Verify that we did the right thing | |
| 509 verify_single_block(pref_addr, left_blk_size); | |
| 510 verify_single_block(suff_addr, blk_size - left_blk_size); | |
| 511 } | |
| 512 | |
| 513 | |
| 514 // Mark the BOT such that if [blk_start, blk_end) straddles a card | |
| 515 // boundary, the card following the first such boundary is marked | |
| 516 // with the appropriate offset. | |
| 517 // NOTE: this method does _not_ adjust _unallocated_block or | |
| 518 // any cards subsequent to the first one. | |
| 519 void | |
| 520 BlockOffsetArrayNonContigSpace::mark_block(HeapWord* blk_start, | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
521 HeapWord* blk_end, bool reducing) { |
|
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
522 do_block_internal(blk_start, blk_end, Action_mark, reducing); |
| 0 | 523 } |
| 524 | |
| 525 HeapWord* BlockOffsetArrayNonContigSpace::block_start_unsafe( | |
| 526 const void* addr) const { | |
| 527 assert(_array->offset_array(0) == 0, "objects can't cross covered areas"); | |
| 528 assert(_bottom <= addr && addr < _end, | |
| 529 "addr must be covered by this Array"); | |
| 530 // Must read this exactly once because it can be modified by parallel | |
| 531 // allocation. | |
| 532 HeapWord* ub = _unallocated_block; | |
| 533 if (BlockOffsetArrayUseUnallocatedBlock && addr >= ub) { | |
| 534 assert(ub < _end, "tautology (see above)"); | |
| 535 return ub; | |
| 536 } | |
| 537 | |
| 538 // Otherwise, find the block start using the table. | |
| 539 size_t index = _array->index_for(addr); | |
| 540 HeapWord* q = _array->address_for_index(index); | |
| 541 | |
| 542 uint offset = _array->offset_array(index); // Extend u_char to uint. | |
| 543 while (offset >= N_words) { | |
| 544 // The excess of the offset from N_words indicates a power of Base | |
| 545 // to go back by. | |
| 546 size_t n_cards_back = entry_to_cards_back(offset); | |
| 547 q -= (N_words * n_cards_back); | |
|
3359
7d64aa23eb96
7043891: CMS: assert(_whole_heap.contains(p)) failed: out of bounds access to card marking array
ysr
parents:
1972
diff
changeset
|
548 assert(q >= _sp->bottom(), |
|
7d64aa23eb96
7043891: CMS: assert(_whole_heap.contains(p)) failed: out of bounds access to card marking array
ysr
parents:
1972
diff
changeset
|
549 err_msg("q = " PTR_FORMAT " crossed below bottom = " PTR_FORMAT, |
|
7d64aa23eb96
7043891: CMS: assert(_whole_heap.contains(p)) failed: out of bounds access to card marking array
ysr
parents:
1972
diff
changeset
|
550 q, _sp->bottom())); |
|
7d64aa23eb96
7043891: CMS: assert(_whole_heap.contains(p)) failed: out of bounds access to card marking array
ysr
parents:
1972
diff
changeset
|
551 assert(q < _sp->end(), |
|
7d64aa23eb96
7043891: CMS: assert(_whole_heap.contains(p)) failed: out of bounds access to card marking array
ysr
parents:
1972
diff
changeset
|
552 err_msg("q = " PTR_FORMAT " crossed above end = " PTR_FORMAT, |
|
7d64aa23eb96
7043891: CMS: assert(_whole_heap.contains(p)) failed: out of bounds access to card marking array
ysr
parents:
1972
diff
changeset
|
553 q, _sp->end())); |
| 0 | 554 index -= n_cards_back; |
| 555 offset = _array->offset_array(index); | |
| 556 } | |
| 557 assert(offset < N_words, "offset too large"); | |
| 558 index--; | |
| 559 q -= offset; | |
|
3359
7d64aa23eb96
7043891: CMS: assert(_whole_heap.contains(p)) failed: out of bounds access to card marking array
ysr
parents:
1972
diff
changeset
|
560 assert(q >= _sp->bottom(), |
|
7d64aa23eb96
7043891: CMS: assert(_whole_heap.contains(p)) failed: out of bounds access to card marking array
ysr
parents:
1972
diff
changeset
|
561 err_msg("q = " PTR_FORMAT " crossed below bottom = " PTR_FORMAT, |
|
7d64aa23eb96
7043891: CMS: assert(_whole_heap.contains(p)) failed: out of bounds access to card marking array
ysr
parents:
1972
diff
changeset
|
562 q, _sp->bottom())); |
|
7d64aa23eb96
7043891: CMS: assert(_whole_heap.contains(p)) failed: out of bounds access to card marking array
ysr
parents:
1972
diff
changeset
|
563 assert(q < _sp->end(), |
|
7d64aa23eb96
7043891: CMS: assert(_whole_heap.contains(p)) failed: out of bounds access to card marking array
ysr
parents:
1972
diff
changeset
|
564 err_msg("q = " PTR_FORMAT " crossed above end = " PTR_FORMAT, |
|
7d64aa23eb96
7043891: CMS: assert(_whole_heap.contains(p)) failed: out of bounds access to card marking array
ysr
parents:
1972
diff
changeset
|
565 q, _sp->end())); |
| 0 | 566 HeapWord* n = q; |
| 567 | |
| 568 while (n <= addr) { | |
| 569 debug_only(HeapWord* last = q); // for debugging | |
| 570 q = n; | |
| 571 n += _sp->block_size(n); | |
|
3359
7d64aa23eb96
7043891: CMS: assert(_whole_heap.contains(p)) failed: out of bounds access to card marking array
ysr
parents:
1972
diff
changeset
|
572 assert(n > q, |
|
3746
537a4053b0f9
7042740: CMS: assert(n> q) failed: Looping at: ... blockOffsetTable.cpp:557
ysr
parents:
3359
diff
changeset
|
573 err_msg("Looping at n = " PTR_FORMAT " with last = " PTR_FORMAT"," |
|
537a4053b0f9
7042740: CMS: assert(n> q) failed: Looping at: ... blockOffsetTable.cpp:557
ysr
parents:
3359
diff
changeset
|
574 " while querying blk_start(" PTR_FORMAT ")" |
|
537a4053b0f9
7042740: CMS: assert(n> q) failed: Looping at: ... blockOffsetTable.cpp:557
ysr
parents:
3359
diff
changeset
|
575 " on _sp = [" PTR_FORMAT "," PTR_FORMAT ")", |
|
537a4053b0f9
7042740: CMS: assert(n> q) failed: Looping at: ... blockOffsetTable.cpp:557
ysr
parents:
3359
diff
changeset
|
576 n, last, addr, _sp->bottom(), _sp->end())); |
| 0 | 577 } |
|
3746
537a4053b0f9
7042740: CMS: assert(n> q) failed: Looping at: ... blockOffsetTable.cpp:557
ysr
parents:
3359
diff
changeset
|
578 assert(q <= addr, |
|
537a4053b0f9
7042740: CMS: assert(n> q) failed: Looping at: ... blockOffsetTable.cpp:557
ysr
parents:
3359
diff
changeset
|
579 err_msg("wrong order for current (" INTPTR_FORMAT ")" " <= arg (" INTPTR_FORMAT ")", |
|
537a4053b0f9
7042740: CMS: assert(n> q) failed: Looping at: ... blockOffsetTable.cpp:557
ysr
parents:
3359
diff
changeset
|
580 q, addr)); |
|
537a4053b0f9
7042740: CMS: assert(n> q) failed: Looping at: ... blockOffsetTable.cpp:557
ysr
parents:
3359
diff
changeset
|
581 assert(addr <= n, |
|
537a4053b0f9
7042740: CMS: assert(n> q) failed: Looping at: ... blockOffsetTable.cpp:557
ysr
parents:
3359
diff
changeset
|
582 err_msg("wrong order for arg (" INTPTR_FORMAT ") <= next (" INTPTR_FORMAT ")", |
|
537a4053b0f9
7042740: CMS: assert(n> q) failed: Looping at: ... blockOffsetTable.cpp:557
ysr
parents:
3359
diff
changeset
|
583 addr, n)); |
| 0 | 584 return q; |
| 585 } | |
| 586 | |
| 587 HeapWord* BlockOffsetArrayNonContigSpace::block_start_careful( | |
| 588 const void* addr) const { | |
| 589 assert(_array->offset_array(0) == 0, "objects can't cross covered areas"); | |
| 590 | |
| 591 assert(_bottom <= addr && addr < _end, | |
| 592 "addr must be covered by this Array"); | |
| 593 // Must read this exactly once because it can be modified by parallel | |
| 594 // allocation. | |
| 595 HeapWord* ub = _unallocated_block; | |
| 596 if (BlockOffsetArrayUseUnallocatedBlock && addr >= ub) { | |
| 597 assert(ub < _end, "tautology (see above)"); | |
| 598 return ub; | |
| 599 } | |
| 600 | |
| 601 // Otherwise, find the block start using the table, but taking | |
| 602 // care (cf block_start_unsafe() above) not to parse any objects/blocks | |
| 603 // on the cards themsleves. | |
| 604 size_t index = _array->index_for(addr); | |
| 605 assert(_array->address_for_index(index) == addr, | |
| 606 "arg should be start of card"); | |
| 607 | |
| 608 HeapWord* q = (HeapWord*)addr; | |
| 609 uint offset; | |
| 610 do { | |
| 611 offset = _array->offset_array(index); | |
| 612 if (offset < N_words) { | |
| 613 q -= offset; | |
| 614 } else { | |
| 615 size_t n_cards_back = entry_to_cards_back(offset); | |
| 616 q -= (n_cards_back * N_words); | |
| 617 index -= n_cards_back; | |
| 618 } | |
| 619 } while (offset >= N_words); | |
| 620 assert(q <= addr, "block start should be to left of arg"); | |
| 621 return q; | |
| 622 } | |
| 623 | |
| 624 #ifndef PRODUCT | |
| 625 // Verification & debugging - ensure that the offset table reflects the fact | |
| 626 // that the block [blk_start, blk_end) or [blk, blk + size) is a | |
| 627 // single block of storage. NOTE: can't const this because of | |
| 628 // call to non-const do_block_internal() below. | |
| 629 void BlockOffsetArrayNonContigSpace::verify_single_block( | |
| 630 HeapWord* blk_start, HeapWord* blk_end) { | |
| 631 if (VerifyBlockOffsetArray) { | |
| 632 do_block_internal(blk_start, blk_end, Action_check); | |
| 633 } | |
| 634 } | |
| 635 | |
| 636 void BlockOffsetArrayNonContigSpace::verify_single_block( | |
| 637 HeapWord* blk, size_t size) { | |
| 638 verify_single_block(blk, blk + size); | |
| 639 } | |
| 640 | |
| 641 // Verify that the given block is before _unallocated_block | |
| 642 void BlockOffsetArrayNonContigSpace::verify_not_unallocated( | |
| 643 HeapWord* blk_start, HeapWord* blk_end) const { | |
| 644 if (BlockOffsetArrayUseUnallocatedBlock) { | |
| 645 assert(blk_start < blk_end, "Block inconsistency?"); | |
| 646 assert(blk_end <= _unallocated_block, "_unallocated_block problem"); | |
| 647 } | |
| 648 } | |
| 649 | |
| 650 void BlockOffsetArrayNonContigSpace::verify_not_unallocated( | |
| 651 HeapWord* blk, size_t size) const { | |
| 652 verify_not_unallocated(blk, blk + size); | |
| 653 } | |
| 654 #endif // PRODUCT | |
| 655 | |
| 656 size_t BlockOffsetArrayNonContigSpace::last_active_index() const { | |
| 657 if (_unallocated_block == _bottom) { | |
| 658 return 0; | |
| 659 } else { | |
| 660 return _array->index_for(_unallocated_block - 1); | |
| 661 } | |
| 662 } | |
| 663 | |
| 664 ////////////////////////////////////////////////////////////////////// | |
| 665 // BlockOffsetArrayContigSpace | |
| 666 ////////////////////////////////////////////////////////////////////// | |
| 667 | |
| 668 HeapWord* BlockOffsetArrayContigSpace::block_start_unsafe(const void* addr) const { | |
| 669 assert(_array->offset_array(0) == 0, "objects can't cross covered areas"); | |
| 670 | |
| 671 // Otherwise, find the block start using the table. | |
| 672 assert(_bottom <= addr && addr < _end, | |
| 673 "addr must be covered by this Array"); | |
| 674 size_t index = _array->index_for(addr); | |
| 675 // We must make sure that the offset table entry we use is valid. If | |
| 676 // "addr" is past the end, start at the last known one and go forward. | |
| 677 index = MIN2(index, _next_offset_index-1); | |
| 678 HeapWord* q = _array->address_for_index(index); | |
| 679 | |
| 680 uint offset = _array->offset_array(index); // Extend u_char to uint. | |
| 681 while (offset > N_words) { | |
| 682 // The excess of the offset from N_words indicates a power of Base | |
| 683 // to go back by. | |
| 684 size_t n_cards_back = entry_to_cards_back(offset); | |
| 685 q -= (N_words * n_cards_back); | |
| 686 assert(q >= _sp->bottom(), "Went below bottom!"); | |
| 687 index -= n_cards_back; | |
| 688 offset = _array->offset_array(index); | |
| 689 } | |
| 690 while (offset == N_words) { | |
| 691 assert(q >= _sp->bottom(), "Went below bottom!"); | |
| 692 q -= N_words; | |
| 693 index--; | |
| 694 offset = _array->offset_array(index); | |
| 695 } | |
| 696 assert(offset < N_words, "offset too large"); | |
| 697 q -= offset; | |
| 698 HeapWord* n = q; | |
| 699 | |
| 700 while (n <= addr) { | |
| 701 debug_only(HeapWord* last = q); // for debugging | |
| 702 q = n; | |
| 703 n += _sp->block_size(n); | |
| 704 } | |
| 705 assert(q <= addr, "wrong order for current and arg"); | |
| 706 assert(addr <= n, "wrong order for arg and next"); | |
| 707 return q; | |
| 708 } | |
| 709 | |
| 710 // | |
| 711 // _next_offset_threshold | |
| 712 // | _next_offset_index | |
| 713 // v v | |
| 714 // +-------+-------+-------+-------+-------+ | |
| 715 // | i-1 | i | i+1 | i+2 | i+3 | | |
| 716 // +-------+-------+-------+-------+-------+ | |
| 717 // ( ^ ] | |
| 718 // block-start | |
| 719 // | |
| 720 | |
| 721 void BlockOffsetArrayContigSpace::alloc_block_work(HeapWord* blk_start, | |
| 722 HeapWord* blk_end) { | |
| 723 assert(blk_start != NULL && blk_end > blk_start, | |
| 724 "phantom block"); | |
| 725 assert(blk_end > _next_offset_threshold, | |
| 726 "should be past threshold"); | |
| 727 assert(blk_start <= _next_offset_threshold, | |
|
1489
cff162798819
6888953: some calls to function-like macros are missing semicolons
jcoomes
parents:
342
diff
changeset
|
728 "blk_start should be at or before threshold"); |
| 0 | 729 assert(pointer_delta(_next_offset_threshold, blk_start) <= N_words, |
| 730 "offset should be <= BlockOffsetSharedArray::N"); | |
| 731 assert(Universe::heap()->is_in_reserved(blk_start), | |
| 732 "reference must be into the heap"); | |
| 733 assert(Universe::heap()->is_in_reserved(blk_end-1), | |
| 734 "limit must be within the heap"); | |
| 735 assert(_next_offset_threshold == | |
| 736 _array->_reserved.start() + _next_offset_index*N_words, | |
| 737 "index must agree with threshold"); | |
| 738 | |
| 739 debug_only(size_t orig_next_offset_index = _next_offset_index;) | |
| 740 | |
| 741 // Mark the card that holds the offset into the block. Note | |
| 742 // that _next_offset_index and _next_offset_threshold are not | |
| 743 // updated until the end of this method. | |
| 744 _array->set_offset_array(_next_offset_index, | |
| 745 _next_offset_threshold, | |
| 746 blk_start); | |
| 747 | |
| 748 // We need to now mark the subsequent cards that this blk spans. | |
| 749 | |
| 750 // Index of card on which blk ends. | |
| 751 size_t end_index = _array->index_for(blk_end - 1); | |
| 752 | |
| 753 // Are there more cards left to be updated? | |
| 754 if (_next_offset_index + 1 <= end_index) { | |
| 755 HeapWord* rem_st = _array->address_for_index(_next_offset_index + 1); | |
| 756 // Calculate rem_end this way because end_index | |
| 757 // may be the last valid index in the covered region. | |
| 758 HeapWord* rem_end = _array->address_for_index(end_index) + N_words; | |
| 759 set_remainder_to_point_to_start(rem_st, rem_end); | |
| 760 } | |
| 761 | |
| 762 // _next_offset_index and _next_offset_threshold updated here. | |
| 763 _next_offset_index = end_index + 1; | |
| 764 // Calculate _next_offset_threshold this way because end_index | |
| 765 // may be the last valid index in the covered region. | |
|
1716
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
766 _next_offset_threshold = _array->address_for_index(end_index) + N_words; |
|
be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
ysr
parents:
1552
diff
changeset
|
767 assert(_next_offset_threshold >= blk_end, "Incorrect offset threshold"); |
| 0 | 768 |
| 769 #ifdef ASSERT | |
| 770 // The offset can be 0 if the block starts on a boundary. That | |
| 771 // is checked by an assertion above. | |
| 772 size_t start_index = _array->index_for(blk_start); | |
| 773 HeapWord* boundary = _array->address_for_index(start_index); | |
| 774 assert((_array->offset_array(orig_next_offset_index) == 0 && | |
| 775 blk_start == boundary) || | |
| 776 (_array->offset_array(orig_next_offset_index) > 0 && | |
| 777 _array->offset_array(orig_next_offset_index) <= N_words), | |
| 778 "offset array should have been set"); | |
| 779 for (size_t j = orig_next_offset_index + 1; j <= end_index; j++) { | |
| 780 assert(_array->offset_array(j) > 0 && | |
| 781 _array->offset_array(j) <= (u_char) (N_words+N_powers-1), | |
| 782 "offset array should have been set"); | |
| 783 } | |
| 784 #endif | |
| 785 } | |
| 786 | |
| 787 HeapWord* BlockOffsetArrayContigSpace::initialize_threshold() { | |
| 788 assert(!Universe::heap()->is_in_reserved(_array->_offset_array), | |
| 789 "just checking"); | |
| 790 _next_offset_index = _array->index_for(_bottom); | |
| 791 _next_offset_index++; | |
| 792 _next_offset_threshold = | |
| 793 _array->address_for_index(_next_offset_index); | |
| 794 return _next_offset_threshold; | |
| 795 } | |
| 796 | |
| 797 void BlockOffsetArrayContigSpace::zero_bottom_entry() { | |
| 798 assert(!Universe::heap()->is_in_reserved(_array->_offset_array), | |
| 799 "just checking"); | |
| 800 size_t bottom_index = _array->index_for(_bottom); | |
| 801 _array->set_offset_array(bottom_index, 0); | |
| 802 } | |
| 803 | |
| 804 | |
| 805 void BlockOffsetArrayContigSpace::serialize(SerializeOopClosure* soc) { | |
| 806 if (soc->reading()) { | |
| 807 // Null these values so that the serializer won't object to updating them. | |
| 808 _next_offset_threshold = NULL; | |
| 809 _next_offset_index = 0; | |
| 810 } | |
| 811 soc->do_ptr(&_next_offset_threshold); | |
| 812 soc->do_size_t(&_next_offset_index); | |
| 813 } | |
| 814 | |
| 815 size_t BlockOffsetArrayContigSpace::last_active_index() const { | |
| 816 size_t result = _next_offset_index - 1; | |
| 817 return result >= 0 ? result : 0; | |
| 818 } |