annotate src/share/vm/gc_implementation/g1/heapRegion.cpp @ 996:2c79770d1f6e

6819085: G1: use larger and/or user settable region size Summary: Instead of the region size being hard-coded, allow the user to set it. Reviewed-by: jmasa, johnc, apetrusenko
author tonyp
date Thu, 30 Jul 2009 16:22:58 -0400
parents 18f526145aea
children ff2402f6a50b
rev   line source
ysr@345 1 /*
xdono@895 2 * Copyright 2001-2009 Sun Microsystems, Inc. All Rights Reserved.
ysr@345 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
ysr@345 4 *
ysr@345 5 * This code is free software; you can redistribute it and/or modify it
ysr@345 6 * under the terms of the GNU General Public License version 2 only, as
ysr@345 7 * published by the Free Software Foundation.
ysr@345 8 *
ysr@345 9 * This code is distributed in the hope that it will be useful, but WITHOUT
ysr@345 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
ysr@345 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
ysr@345 12 * version 2 for more details (a copy is included in the LICENSE file that
ysr@345 13 * accompanied this code).
ysr@345 14 *
ysr@345 15 * You should have received a copy of the GNU General Public License version
ysr@345 16 * 2 along with this work; if not, write to the Free Software Foundation,
ysr@345 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
ysr@345 18 *
ysr@345 19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
ysr@345 20 * CA 95054 USA or visit www.sun.com if you need additional information or
ysr@345 21 * have any questions.
ysr@345 22 *
ysr@345 23 */
ysr@345 24
ysr@345 25 #include "incls/_precompiled.incl"
ysr@345 26 #include "incls/_heapRegion.cpp.incl"
ysr@345 27
tonyp@996 28 int HeapRegion::LogOfHRGrainBytes = 0;
tonyp@996 29 int HeapRegion::LogOfHRGrainWords = 0;
tonyp@996 30 int HeapRegion::GrainBytes = 0;
tonyp@996 31 int HeapRegion::GrainWords = 0;
tonyp@996 32 int HeapRegion::CardsPerRegion = 0;
tonyp@996 33
ysr@345 34 HeapRegionDCTOC::HeapRegionDCTOC(G1CollectedHeap* g1,
ysr@345 35 HeapRegion* hr, OopClosure* cl,
ysr@345 36 CardTableModRefBS::PrecisionStyle precision,
ysr@345 37 FilterKind fk) :
ysr@345 38 ContiguousSpaceDCTOC(hr, cl, precision, NULL),
ysr@345 39 _hr(hr), _fk(fk), _g1(g1)
ysr@345 40 {}
ysr@345 41
ysr@345 42 FilterOutOfRegionClosure::FilterOutOfRegionClosure(HeapRegion* r,
ysr@345 43 OopClosure* oc) :
ysr@345 44 _r_bottom(r->bottom()), _r_end(r->end()),
ysr@345 45 _oc(oc), _out_of_region(0)
ysr@345 46 {}
ysr@345 47
ysr@345 48 class VerifyLiveClosure: public OopClosure {
tonyp@860 49 private:
ysr@345 50 G1CollectedHeap* _g1h;
ysr@345 51 CardTableModRefBS* _bs;
ysr@345 52 oop _containing_obj;
ysr@345 53 bool _failures;
ysr@345 54 int _n_failures;
tonyp@860 55 bool _use_prev_marking;
ysr@345 56 public:
tonyp@860 57 // use_prev_marking == true -> use "prev" marking information,
tonyp@860 58 // use_prev_marking == false -> use "next" marking information
tonyp@860 59 VerifyLiveClosure(G1CollectedHeap* g1h, bool use_prev_marking) :
ysr@345 60 _g1h(g1h), _bs(NULL), _containing_obj(NULL),
tonyp@860 61 _failures(false), _n_failures(0), _use_prev_marking(use_prev_marking)
ysr@345 62 {
ysr@345 63 BarrierSet* bs = _g1h->barrier_set();
ysr@345 64 if (bs->is_a(BarrierSet::CardTableModRef))
ysr@345 65 _bs = (CardTableModRefBS*)bs;
ysr@345 66 }
ysr@345 67
ysr@345 68 void set_containing_obj(oop obj) {
ysr@345 69 _containing_obj = obj;
ysr@345 70 }
ysr@345 71
ysr@345 72 bool failures() { return _failures; }
ysr@345 73 int n_failures() { return _n_failures; }
ysr@345 74
ysr@896 75 virtual void do_oop(narrowOop* p) { do_oop_work(p); }
ysr@896 76 virtual void do_oop( oop* p) { do_oop_work(p); }
ysr@345 77
ysr@896 78 template <class T> void do_oop_work(T* p) {
ysr@345 79 assert(_containing_obj != NULL, "Precondition");
tonyp@860 80 assert(!_g1h->is_obj_dead_cond(_containing_obj, _use_prev_marking),
tonyp@860 81 "Precondition");
ysr@896 82 T heap_oop = oopDesc::load_heap_oop(p);
ysr@896 83 if (!oopDesc::is_null(heap_oop)) {
ysr@896 84 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
ysr@345 85 bool failed = false;
tonyp@860 86 if (!_g1h->is_in_closed_subset(obj) ||
tonyp@860 87 _g1h->is_obj_dead_cond(obj, _use_prev_marking)) {
ysr@345 88 if (!_failures) {
ysr@345 89 gclog_or_tty->print_cr("");
ysr@345 90 gclog_or_tty->print_cr("----------");
ysr@345 91 }
ysr@345 92 if (!_g1h->is_in_closed_subset(obj)) {
ysr@345 93 gclog_or_tty->print_cr("Field "PTR_FORMAT
ysr@345 94 " of live obj "PTR_FORMAT
ysr@345 95 " points to obj "PTR_FORMAT
ysr@345 96 " not in the heap.",
ysr@345 97 p, (void*) _containing_obj, (void*) obj);
ysr@345 98 } else {
ysr@345 99 gclog_or_tty->print_cr("Field "PTR_FORMAT
ysr@345 100 " of live obj "PTR_FORMAT
ysr@345 101 " points to dead obj "PTR_FORMAT".",
ysr@345 102 p, (void*) _containing_obj, (void*) obj);
ysr@345 103 }
ysr@345 104 gclog_or_tty->print_cr("Live obj:");
ysr@345 105 _containing_obj->print_on(gclog_or_tty);
ysr@345 106 gclog_or_tty->print_cr("Bad referent:");
ysr@345 107 obj->print_on(gclog_or_tty);
ysr@345 108 gclog_or_tty->print_cr("----------");
ysr@345 109 _failures = true;
ysr@345 110 failed = true;
ysr@345 111 _n_failures++;
ysr@345 112 }
ysr@345 113
ysr@345 114 if (!_g1h->full_collection()) {
ysr@896 115 HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p);
ysr@896 116 HeapRegion* to = _g1h->heap_region_containing(obj);
ysr@345 117 if (from != NULL && to != NULL &&
ysr@345 118 from != to &&
ysr@345 119 !to->isHumongous()) {
ysr@345 120 jbyte cv_obj = *_bs->byte_for_const(_containing_obj);
ysr@345 121 jbyte cv_field = *_bs->byte_for_const(p);
ysr@345 122 const jbyte dirty = CardTableModRefBS::dirty_card_val();
ysr@345 123
ysr@345 124 bool is_bad = !(from->is_young()
ysr@345 125 || to->rem_set()->contains_reference(p)
ysr@345 126 || !G1HRRSFlushLogBuffersOnVerify && // buffers were not flushed
ysr@345 127 (_containing_obj->is_objArray() ?
ysr@345 128 cv_field == dirty
ysr@345 129 : cv_obj == dirty || cv_field == dirty));
ysr@345 130 if (is_bad) {
ysr@345 131 if (!_failures) {
ysr@345 132 gclog_or_tty->print_cr("");
ysr@345 133 gclog_or_tty->print_cr("----------");
ysr@345 134 }
ysr@345 135 gclog_or_tty->print_cr("Missing rem set entry:");
ysr@345 136 gclog_or_tty->print_cr("Field "PTR_FORMAT
ysr@345 137 " of obj "PTR_FORMAT
ysr@345 138 ", in region %d ["PTR_FORMAT
ysr@345 139 ", "PTR_FORMAT"),",
ysr@345 140 p, (void*) _containing_obj,
ysr@345 141 from->hrs_index(),
ysr@345 142 from->bottom(),
ysr@345 143 from->end());
ysr@345 144 _containing_obj->print_on(gclog_or_tty);
ysr@345 145 gclog_or_tty->print_cr("points to obj "PTR_FORMAT
ysr@345 146 " in region %d ["PTR_FORMAT
ysr@345 147 ", "PTR_FORMAT").",
ysr@345 148 (void*) obj, to->hrs_index(),
ysr@345 149 to->bottom(), to->end());
ysr@345 150 obj->print_on(gclog_or_tty);
ysr@345 151 gclog_or_tty->print_cr("Obj head CTE = %d, field CTE = %d.",
ysr@345 152 cv_obj, cv_field);
ysr@345 153 gclog_or_tty->print_cr("----------");
ysr@345 154 _failures = true;
ysr@345 155 if (!failed) _n_failures++;
ysr@345 156 }
ysr@345 157 }
ysr@345 158 }
ysr@345 159 }
ysr@345 160 }
ysr@345 161 };
ysr@345 162
ysr@345 163 template<class ClosureType>
ysr@345 164 HeapWord* walk_mem_region_loop(ClosureType* cl, G1CollectedHeap* g1h,
ysr@345 165 HeapRegion* hr,
ysr@345 166 HeapWord* cur, HeapWord* top) {
ysr@345 167 oop cur_oop = oop(cur);
ysr@345 168 int oop_size = cur_oop->size();
ysr@345 169 HeapWord* next_obj = cur + oop_size;
ysr@345 170 while (next_obj < top) {
ysr@345 171 // Keep filtering the remembered set.
ysr@345 172 if (!g1h->is_obj_dead(cur_oop, hr)) {
ysr@345 173 // Bottom lies entirely below top, so we can call the
ysr@345 174 // non-memRegion version of oop_iterate below.
ysr@345 175 cur_oop->oop_iterate(cl);
ysr@345 176 }
ysr@345 177 cur = next_obj;
ysr@345 178 cur_oop = oop(cur);
ysr@345 179 oop_size = cur_oop->size();
ysr@345 180 next_obj = cur + oop_size;
ysr@345 181 }
ysr@345 182 return cur;
ysr@345 183 }
ysr@345 184
ysr@345 185 void HeapRegionDCTOC::walk_mem_region_with_cl(MemRegion mr,
ysr@345 186 HeapWord* bottom,
ysr@345 187 HeapWord* top,
ysr@345 188 OopClosure* cl) {
ysr@345 189 G1CollectedHeap* g1h = _g1;
ysr@345 190
ysr@345 191 int oop_size;
ysr@345 192
ysr@345 193 OopClosure* cl2 = cl;
ysr@345 194 FilterIntoCSClosure intoCSFilt(this, g1h, cl);
ysr@345 195 FilterOutOfRegionClosure outOfRegionFilt(_hr, cl);
ysr@345 196 switch (_fk) {
ysr@345 197 case IntoCSFilterKind: cl2 = &intoCSFilt; break;
ysr@345 198 case OutOfRegionFilterKind: cl2 = &outOfRegionFilt; break;
ysr@345 199 }
ysr@345 200
ysr@345 201 // Start filtering what we add to the remembered set. If the object is
ysr@345 202 // not considered dead, either because it is marked (in the mark bitmap)
ysr@345 203 // or it was allocated after marking finished, then we add it. Otherwise
ysr@345 204 // we can safely ignore the object.
ysr@345 205 if (!g1h->is_obj_dead(oop(bottom), _hr)) {
ysr@345 206 oop_size = oop(bottom)->oop_iterate(cl2, mr);
ysr@345 207 } else {
ysr@345 208 oop_size = oop(bottom)->size();
ysr@345 209 }
ysr@345 210
ysr@345 211 bottom += oop_size;
ysr@345 212
ysr@345 213 if (bottom < top) {
ysr@345 214 // We replicate the loop below for several kinds of possible filters.
ysr@345 215 switch (_fk) {
ysr@345 216 case NoFilterKind:
ysr@345 217 bottom = walk_mem_region_loop(cl, g1h, _hr, bottom, top);
ysr@345 218 break;
ysr@345 219 case IntoCSFilterKind: {
ysr@345 220 FilterIntoCSClosure filt(this, g1h, cl);
ysr@345 221 bottom = walk_mem_region_loop(&filt, g1h, _hr, bottom, top);
ysr@345 222 break;
ysr@345 223 }
ysr@345 224 case OutOfRegionFilterKind: {
ysr@345 225 FilterOutOfRegionClosure filt(_hr, cl);
ysr@345 226 bottom = walk_mem_region_loop(&filt, g1h, _hr, bottom, top);
ysr@345 227 break;
ysr@345 228 }
ysr@345 229 default:
ysr@345 230 ShouldNotReachHere();
ysr@345 231 }
ysr@345 232
ysr@345 233 // Last object. Need to do dead-obj filtering here too.
ysr@345 234 if (!g1h->is_obj_dead(oop(bottom), _hr)) {
ysr@345 235 oop(bottom)->oop_iterate(cl2, mr);
ysr@345 236 }
ysr@345 237 }
ysr@345 238 }
ysr@345 239
tonyp@996 240 // Minimum region size; we won't go lower than that.
tonyp@996 241 // We might want to decrease this in the future, to deal with small
tonyp@996 242 // heaps a bit more efficiently.
tonyp@996 243 #define MIN_REGION_SIZE ( 1024 * 1024 )
tonyp@996 244
tonyp@996 245 // Maximum region size; we don't go higher than that. There's a good
tonyp@996 246 // reason for having an upper bound. We don't want regions to get too
tonyp@996 247 // large, otherwise cleanup's effectiveness would decrease as there
tonyp@996 248 // will be fewer opportunities to find totally empty regions after
tonyp@996 249 // marking.
tonyp@996 250 #define MAX_REGION_SIZE ( 32 * 1024 * 1024 )
tonyp@996 251
tonyp@996 252 // The automatic region size calculation will try to have around this
tonyp@996 253 // many regions in the heap (based on the min heap size).
tonyp@996 254 #define TARGET_REGION_NUMBER 2048
tonyp@996 255
tonyp@996 256 void HeapRegion::setup_heap_region_size(uintx min_heap_size) {
tonyp@996 257 // region_size in bytes
tonyp@996 258 uintx region_size = G1HeapRegionSize;
tonyp@996 259 if (FLAG_IS_DEFAULT(G1HeapRegionSize)) {
tonyp@996 260 // We base the automatic calculation on the min heap size. This
tonyp@996 261 // can be problematic if the spread between min and max is quite
tonyp@996 262 // wide, imagine -Xms128m -Xmx32g. But, if we decided it based on
tonyp@996 263 // the max size, the region size might be way too large for the
tonyp@996 264 // min size. Either way, some users might have to set the region
tonyp@996 265 // size manually for some -Xms / -Xmx combos.
tonyp@996 266
tonyp@996 267 region_size = MAX2(min_heap_size / TARGET_REGION_NUMBER,
tonyp@996 268 (uintx) MIN_REGION_SIZE);
tonyp@996 269 }
tonyp@996 270
tonyp@996 271 int region_size_log = log2_long((jlong) region_size);
tonyp@996 272 // Recalculate the region size to make sure it's a power of
tonyp@996 273 // 2. This means that region_size is the largest power of 2 that's
tonyp@996 274 // <= what we've calculated so far.
tonyp@996 275 region_size = 1 << region_size_log;
tonyp@996 276
tonyp@996 277 // Now make sure that we don't go over or under our limits.
tonyp@996 278 if (region_size < MIN_REGION_SIZE) {
tonyp@996 279 region_size = MIN_REGION_SIZE;
tonyp@996 280 } else if (region_size > MAX_REGION_SIZE) {
tonyp@996 281 region_size = MAX_REGION_SIZE;
tonyp@996 282 }
tonyp@996 283
tonyp@996 284 // And recalculate the log.
tonyp@996 285 region_size_log = log2_long((jlong) region_size);
tonyp@996 286
tonyp@996 287 // Now, set up the globals.
tonyp@996 288 guarantee(LogOfHRGrainBytes == 0, "we should only set it once");
tonyp@996 289 LogOfHRGrainBytes = region_size_log;
tonyp@996 290
tonyp@996 291 guarantee(LogOfHRGrainWords == 0, "we should only set it once");
tonyp@996 292 LogOfHRGrainWords = LogOfHRGrainBytes - LogHeapWordSize;
tonyp@996 293
tonyp@996 294 guarantee(GrainBytes == 0, "we should only set it once");
tonyp@996 295 // The cast to int is safe, given that we've bounded region_size by
tonyp@996 296 // MIN_REGION_SIZE and MAX_REGION_SIZE.
tonyp@996 297 GrainBytes = (int) region_size;
tonyp@996 298
tonyp@996 299 guarantee(GrainWords == 0, "we should only set it once");
tonyp@996 300 GrainWords = GrainBytes >> LogHeapWordSize;
tonyp@996 301 guarantee(1 << LogOfHRGrainWords == GrainWords, "sanity");
tonyp@996 302
tonyp@996 303 guarantee(CardsPerRegion == 0, "we should only set it once");
tonyp@996 304 CardsPerRegion = GrainBytes >> CardTableModRefBS::card_shift;
tonyp@996 305 }
tonyp@996 306
ysr@345 307 void HeapRegion::reset_after_compaction() {
ysr@345 308 G1OffsetTableContigSpace::reset_after_compaction();
ysr@345 309 // After a compaction the mark bitmap is invalid, so we must
ysr@345 310 // treat all objects as being inside the unmarked area.
ysr@345 311 zero_marked_bytes();
ysr@345 312 init_top_at_mark_start();
ysr@345 313 }
ysr@345 314
ysr@345 315 DirtyCardToOopClosure*
ysr@345 316 HeapRegion::new_dcto_closure(OopClosure* cl,
ysr@345 317 CardTableModRefBS::PrecisionStyle precision,
ysr@345 318 HeapRegionDCTOC::FilterKind fk) {
ysr@345 319 return new HeapRegionDCTOC(G1CollectedHeap::heap(),
ysr@345 320 this, cl, precision, fk);
ysr@345 321 }
ysr@345 322
ysr@345 323 void HeapRegion::hr_clear(bool par, bool clear_space) {
tonyp@358 324 _humongous_type = NotHumongous;
ysr@345 325 _humongous_start_region = NULL;
ysr@345 326 _in_collection_set = false;
ysr@345 327 _is_gc_alloc_region = false;
ysr@345 328
ysr@345 329 // Age stuff (if parallel, this will be done separately, since it needs
ysr@345 330 // to be sequential).
ysr@345 331 G1CollectedHeap* g1h = G1CollectedHeap::heap();
ysr@345 332
ysr@345 333 set_young_index_in_cset(-1);
ysr@345 334 uninstall_surv_rate_group();
ysr@345 335 set_young_type(NotYoung);
ysr@345 336
ysr@345 337 // In case it had been the start of a humongous sequence, reset its end.
ysr@345 338 set_end(_orig_end);
ysr@345 339
ysr@345 340 if (!par) {
ysr@345 341 // If this is parallel, this will be done later.
ysr@345 342 HeapRegionRemSet* hrrs = rem_set();
ysr@345 343 if (hrrs != NULL) hrrs->clear();
tonyp@358 344 _claimed = InitialClaimValue;
ysr@345 345 }
ysr@345 346 zero_marked_bytes();
ysr@345 347 set_sort_index(-1);
ysr@345 348
ysr@345 349 _offsets.resize(HeapRegion::GrainWords);
ysr@345 350 init_top_at_mark_start();
tonyp@359 351 if (clear_space) clear(SpaceDecorator::Mangle);
ysr@345 352 }
ysr@345 353
ysr@345 354 // <PREDICTION>
ysr@345 355 void HeapRegion::calc_gc_efficiency() {
ysr@345 356 G1CollectedHeap* g1h = G1CollectedHeap::heap();
ysr@345 357 _gc_efficiency = (double) garbage_bytes() /
ysr@345 358 g1h->predict_region_elapsed_time_ms(this, false);
ysr@345 359 }
ysr@345 360 // </PREDICTION>
ysr@345 361
ysr@345 362 void HeapRegion::set_startsHumongous() {
tonyp@358 363 _humongous_type = StartsHumongous;
ysr@345 364 _humongous_start_region = this;
ysr@345 365 assert(end() == _orig_end, "Should be normal before alloc.");
ysr@345 366 }
ysr@345 367
ysr@345 368 bool HeapRegion::claimHeapRegion(jint claimValue) {
ysr@345 369 jint current = _claimed;
ysr@345 370 if (current != claimValue) {
ysr@345 371 jint res = Atomic::cmpxchg(claimValue, &_claimed, current);
ysr@345 372 if (res == current) {
ysr@345 373 return true;
ysr@345 374 }
ysr@345 375 }
ysr@345 376 return false;
ysr@345 377 }
ysr@345 378
ysr@345 379 HeapWord* HeapRegion::next_block_start_careful(HeapWord* addr) {
ysr@345 380 HeapWord* low = addr;
ysr@345 381 HeapWord* high = end();
ysr@345 382 while (low < high) {
ysr@345 383 size_t diff = pointer_delta(high, low);
ysr@345 384 // Must add one below to bias toward the high amount. Otherwise, if
ysr@345 385 // "high" were at the desired value, and "low" were one less, we
ysr@345 386 // would not converge on "high". This is not symmetric, because
ysr@345 387 // we set "high" to a block start, which might be the right one,
ysr@345 388 // which we don't do for "low".
ysr@345 389 HeapWord* middle = low + (diff+1)/2;
ysr@345 390 if (middle == high) return high;
ysr@345 391 HeapWord* mid_bs = block_start_careful(middle);
ysr@345 392 if (mid_bs < addr) {
ysr@345 393 low = middle;
ysr@345 394 } else {
ysr@345 395 high = mid_bs;
ysr@345 396 }
ysr@345 397 }
ysr@345 398 assert(low == high && low >= addr, "Didn't work.");
ysr@345 399 return low;
ysr@345 400 }
ysr@345 401
ysr@345 402 void HeapRegion::set_next_on_unclean_list(HeapRegion* r) {
ysr@345 403 assert(r == NULL || r->is_on_unclean_list(), "Malformed unclean list.");
ysr@345 404 _next_in_special_set = r;
ysr@345 405 }
ysr@345 406
ysr@345 407 void HeapRegion::set_on_unclean_list(bool b) {
ysr@345 408 _is_on_unclean_list = b;
ysr@345 409 }
ysr@345 410
tonyp@359 411 void HeapRegion::initialize(MemRegion mr, bool clear_space, bool mangle_space) {
tonyp@359 412 G1OffsetTableContigSpace::initialize(mr, false, mangle_space);
ysr@345 413 hr_clear(false/*par*/, clear_space);
ysr@345 414 }
ysr@345 415 #ifdef _MSC_VER // the use of 'this' below gets a warning, make it go away
ysr@345 416 #pragma warning( disable:4355 ) // 'this' : used in base member initializer list
ysr@345 417 #endif // _MSC_VER
ysr@345 418
ysr@345 419
ysr@345 420 HeapRegion::
ysr@345 421 HeapRegion(G1BlockOffsetSharedArray* sharedOffsetArray,
ysr@345 422 MemRegion mr, bool is_zeroed)
ysr@345 423 : G1OffsetTableContigSpace(sharedOffsetArray, mr, is_zeroed),
ysr@345 424 _next_fk(HeapRegionDCTOC::NoFilterKind),
ysr@345 425 _hrs_index(-1),
tonyp@358 426 _humongous_type(NotHumongous), _humongous_start_region(NULL),
ysr@345 427 _in_collection_set(false), _is_gc_alloc_region(false),
ysr@345 428 _is_on_free_list(false), _is_on_unclean_list(false),
ysr@345 429 _next_in_special_set(NULL), _orig_end(NULL),
tonyp@358 430 _claimed(InitialClaimValue), _evacuation_failed(false),
ysr@345 431 _prev_marked_bytes(0), _next_marked_bytes(0), _sort_index(-1),
ysr@345 432 _young_type(NotYoung), _next_young_region(NULL),
apetrusenko@844 433 _next_dirty_cards_region(NULL),
ysr@345 434 _young_index_in_cset(-1), _surv_rate_group(NULL), _age_index(-1),
ysr@345 435 _rem_set(NULL), _zfs(NotZeroFilled)
ysr@345 436 {
ysr@345 437 _orig_end = mr.end();
ysr@345 438 // Note that initialize() will set the start of the unmarked area of the
ysr@345 439 // region.
tonyp@359 440 this->initialize(mr, !is_zeroed, SpaceDecorator::Mangle);
tonyp@359 441 set_top(bottom());
tonyp@359 442 set_saved_mark();
ysr@345 443
ysr@345 444 _rem_set = new HeapRegionRemSet(sharedOffsetArray, this);
ysr@345 445
ysr@345 446 assert(HeapRegionRemSet::num_par_rem_sets() > 0, "Invariant.");
ysr@345 447 // In case the region is allocated during a pause, note the top.
ysr@345 448 // We haven't done any counting on a brand new region.
ysr@345 449 _top_at_conc_mark_count = bottom();
ysr@345 450 }
ysr@345 451
ysr@345 452 class NextCompactionHeapRegionClosure: public HeapRegionClosure {
ysr@345 453 const HeapRegion* _target;
ysr@345 454 bool _target_seen;
ysr@345 455 HeapRegion* _last;
ysr@345 456 CompactibleSpace* _res;
ysr@345 457 public:
ysr@345 458 NextCompactionHeapRegionClosure(const HeapRegion* target) :
ysr@345 459 _target(target), _target_seen(false), _res(NULL) {}
ysr@345 460 bool doHeapRegion(HeapRegion* cur) {
ysr@345 461 if (_target_seen) {
ysr@345 462 if (!cur->isHumongous()) {
ysr@345 463 _res = cur;
ysr@345 464 return true;
ysr@345 465 }
ysr@345 466 } else if (cur == _target) {
ysr@345 467 _target_seen = true;
ysr@345 468 }
ysr@345 469 return false;
ysr@345 470 }
ysr@345 471 CompactibleSpace* result() { return _res; }
ysr@345 472 };
ysr@345 473
ysr@345 474 CompactibleSpace* HeapRegion::next_compaction_space() const {
ysr@345 475 G1CollectedHeap* g1h = G1CollectedHeap::heap();
ysr@345 476 // cast away const-ness
ysr@345 477 HeapRegion* r = (HeapRegion*) this;
ysr@345 478 NextCompactionHeapRegionClosure blk(r);
ysr@345 479 g1h->heap_region_iterate_from(r, &blk);
ysr@345 480 return blk.result();
ysr@345 481 }
ysr@345 482
ysr@345 483 void HeapRegion::set_continuesHumongous(HeapRegion* start) {
ysr@345 484 // The order is important here.
ysr@345 485 start->add_continuingHumongousRegion(this);
tonyp@358 486 _humongous_type = ContinuesHumongous;
ysr@345 487 _humongous_start_region = start;
ysr@345 488 }
ysr@345 489
ysr@345 490 void HeapRegion::add_continuingHumongousRegion(HeapRegion* cont) {
ysr@345 491 // Must join the blocks of the current H region seq with the block of the
ysr@345 492 // added region.
ysr@345 493 offsets()->join_blocks(bottom(), cont->bottom());
ysr@345 494 arrayOop obj = (arrayOop)(bottom());
ysr@345 495 obj->set_length((int) (obj->length() + cont->capacity()/jintSize));
ysr@345 496 set_end(cont->end());
ysr@345 497 set_top(cont->end());
ysr@345 498 }
ysr@345 499
ysr@345 500 void HeapRegion::save_marks() {
ysr@345 501 set_saved_mark();
ysr@345 502 }
ysr@345 503
ysr@345 504 void HeapRegion::oops_in_mr_iterate(MemRegion mr, OopClosure* cl) {
ysr@345 505 HeapWord* p = mr.start();
ysr@345 506 HeapWord* e = mr.end();
ysr@345 507 oop obj;
ysr@345 508 while (p < e) {
ysr@345 509 obj = oop(p);
ysr@345 510 p += obj->oop_iterate(cl);
ysr@345 511 }
ysr@345 512 assert(p == e, "bad memregion: doesn't end on obj boundary");
ysr@345 513 }
ysr@345 514
ysr@345 515 #define HeapRegion_OOP_SINCE_SAVE_MARKS_DEFN(OopClosureType, nv_suffix) \
ysr@345 516 void HeapRegion::oop_since_save_marks_iterate##nv_suffix(OopClosureType* cl) { \
ysr@345 517 ContiguousSpace::oop_since_save_marks_iterate##nv_suffix(cl); \
ysr@345 518 }
ysr@345 519 SPECIALIZED_SINCE_SAVE_MARKS_CLOSURES(HeapRegion_OOP_SINCE_SAVE_MARKS_DEFN)
ysr@345 520
ysr@345 521
ysr@345 522 void HeapRegion::oop_before_save_marks_iterate(OopClosure* cl) {
ysr@345 523 oops_in_mr_iterate(MemRegion(bottom(), saved_mark_word()), cl);
ysr@345 524 }
ysr@345 525
ysr@345 526 #ifdef DEBUG
ysr@345 527 HeapWord* HeapRegion::allocate(size_t size) {
ysr@345 528 jint state = zero_fill_state();
ysr@345 529 assert(!G1CollectedHeap::heap()->allocs_are_zero_filled() ||
ysr@345 530 zero_fill_is_allocated(),
ysr@345 531 "When ZF is on, only alloc in ZF'd regions");
ysr@345 532 return G1OffsetTableContigSpace::allocate(size);
ysr@345 533 }
ysr@345 534 #endif
ysr@345 535
ysr@345 536 void HeapRegion::set_zero_fill_state_work(ZeroFillState zfs) {
ysr@345 537 assert(top() == bottom() || zfs == Allocated,
ysr@345 538 "Region must be empty, or we must be setting it to allocated.");
ysr@345 539 assert(ZF_mon->owned_by_self() ||
ysr@345 540 Universe::heap()->is_gc_active(),
ysr@345 541 "Must hold the lock or be a full GC to modify.");
ysr@345 542 _zfs = zfs;
ysr@345 543 }
ysr@345 544
ysr@345 545 void HeapRegion::set_zero_fill_complete() {
ysr@345 546 set_zero_fill_state_work(ZeroFilled);
ysr@345 547 if (ZF_mon->owned_by_self()) {
ysr@345 548 ZF_mon->notify_all();
ysr@345 549 }
ysr@345 550 }
ysr@345 551
ysr@345 552
ysr@345 553 void HeapRegion::ensure_zero_filled() {
ysr@345 554 MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
ysr@345 555 ensure_zero_filled_locked();
ysr@345 556 }
ysr@345 557
ysr@345 558 void HeapRegion::ensure_zero_filled_locked() {
ysr@345 559 assert(ZF_mon->owned_by_self(), "Precondition");
ysr@345 560 bool should_ignore_zf = SafepointSynchronize::is_at_safepoint();
ysr@345 561 assert(should_ignore_zf || Heap_lock->is_locked(),
ysr@345 562 "Either we're in a GC or we're allocating a region.");
ysr@345 563 switch (zero_fill_state()) {
ysr@345 564 case HeapRegion::NotZeroFilled:
ysr@345 565 set_zero_fill_in_progress(Thread::current());
ysr@345 566 {
ysr@345 567 ZF_mon->unlock();
ysr@345 568 Copy::fill_to_words(bottom(), capacity()/HeapWordSize);
ysr@345 569 ZF_mon->lock_without_safepoint_check();
ysr@345 570 }
ysr@345 571 // A trap.
ysr@345 572 guarantee(zero_fill_state() == HeapRegion::ZeroFilling
ysr@345 573 && zero_filler() == Thread::current(),
ysr@345 574 "AHA! Tell Dave D if you see this...");
ysr@345 575 set_zero_fill_complete();
ysr@345 576 // gclog_or_tty->print_cr("Did sync ZF.");
ysr@345 577 ConcurrentZFThread::note_sync_zfs();
ysr@345 578 break;
ysr@345 579 case HeapRegion::ZeroFilling:
ysr@345 580 if (should_ignore_zf) {
ysr@345 581 // We can "break" the lock and take over the work.
ysr@345 582 Copy::fill_to_words(bottom(), capacity()/HeapWordSize);
ysr@345 583 set_zero_fill_complete();
ysr@345 584 ConcurrentZFThread::note_sync_zfs();
ysr@345 585 break;
ysr@345 586 } else {
ysr@345 587 ConcurrentZFThread::wait_for_ZF_completed(this);
ysr@345 588 }
ysr@345 589 case HeapRegion::ZeroFilled:
ysr@345 590 // Nothing to do.
ysr@345 591 break;
ysr@345 592 case HeapRegion::Allocated:
ysr@345 593 guarantee(false, "Should not call on allocated regions.");
ysr@345 594 }
ysr@345 595 assert(zero_fill_state() == HeapRegion::ZeroFilled, "Post");
ysr@345 596 }
ysr@345 597
ysr@345 598 HeapWord*
ysr@345 599 HeapRegion::object_iterate_mem_careful(MemRegion mr,
ysr@345 600 ObjectClosure* cl) {
ysr@345 601 G1CollectedHeap* g1h = G1CollectedHeap::heap();
ysr@345 602 // We used to use "block_start_careful" here. But we're actually happy
ysr@345 603 // to update the BOT while we do this...
ysr@345 604 HeapWord* cur = block_start(mr.start());
ysr@345 605 mr = mr.intersection(used_region());
ysr@345 606 if (mr.is_empty()) return NULL;
ysr@345 607 // Otherwise, find the obj that extends onto mr.start().
ysr@345 608
ysr@345 609 assert(cur <= mr.start()
ysr@896 610 && (oop(cur)->klass_or_null() == NULL ||
ysr@345 611 cur + oop(cur)->size() > mr.start()),
ysr@345 612 "postcondition of block_start");
ysr@345 613 oop obj;
ysr@345 614 while (cur < mr.end()) {
ysr@345 615 obj = oop(cur);
ysr@896 616 if (obj->klass_or_null() == NULL) {
ysr@345 617 // Ran into an unparseable point.
ysr@345 618 return cur;
ysr@345 619 } else if (!g1h->is_obj_dead(obj)) {
ysr@345 620 cl->do_object(obj);
ysr@345 621 }
ysr@345 622 if (cl->abort()) return cur;
ysr@345 623 // The check above must occur before the operation below, since an
ysr@345 624 // abort might invalidate the "size" operation.
ysr@345 625 cur += obj->size();
ysr@345 626 }
ysr@345 627 return NULL;
ysr@345 628 }
ysr@345 629
ysr@345 630 HeapWord*
ysr@345 631 HeapRegion::
ysr@345 632 oops_on_card_seq_iterate_careful(MemRegion mr,
ysr@345 633 FilterOutOfRegionClosure* cl) {
ysr@345 634 G1CollectedHeap* g1h = G1CollectedHeap::heap();
ysr@345 635
ysr@345 636 // If we're within a stop-world GC, then we might look at a card in a
ysr@345 637 // GC alloc region that extends onto a GC LAB, which may not be
ysr@345 638 // parseable. Stop such at the "saved_mark" of the region.
ysr@345 639 if (G1CollectedHeap::heap()->is_gc_active()) {
ysr@345 640 mr = mr.intersection(used_region_at_save_marks());
ysr@345 641 } else {
ysr@345 642 mr = mr.intersection(used_region());
ysr@345 643 }
ysr@345 644 if (mr.is_empty()) return NULL;
ysr@345 645 // Otherwise, find the obj that extends onto mr.start().
ysr@345 646
ysr@345 647 // We used to use "block_start_careful" here. But we're actually happy
ysr@345 648 // to update the BOT while we do this...
ysr@345 649 HeapWord* cur = block_start(mr.start());
ysr@345 650 assert(cur <= mr.start(), "Postcondition");
ysr@345 651
ysr@345 652 while (cur <= mr.start()) {
ysr@896 653 if (oop(cur)->klass_or_null() == NULL) {
ysr@345 654 // Ran into an unparseable point.
ysr@345 655 return cur;
ysr@345 656 }
ysr@345 657 // Otherwise...
ysr@345 658 int sz = oop(cur)->size();
ysr@345 659 if (cur + sz > mr.start()) break;
ysr@345 660 // Otherwise, go on.
ysr@345 661 cur = cur + sz;
ysr@345 662 }
ysr@345 663 oop obj;
ysr@345 664 obj = oop(cur);
ysr@345 665 // If we finish this loop...
ysr@345 666 assert(cur <= mr.start()
ysr@896 667 && obj->klass_or_null() != NULL
ysr@345 668 && cur + obj->size() > mr.start(),
ysr@345 669 "Loop postcondition");
ysr@345 670 if (!g1h->is_obj_dead(obj)) {
ysr@345 671 obj->oop_iterate(cl, mr);
ysr@345 672 }
ysr@345 673
ysr@345 674 HeapWord* next;
ysr@345 675 while (cur < mr.end()) {
ysr@345 676 obj = oop(cur);
ysr@896 677 if (obj->klass_or_null() == NULL) {
ysr@345 678 // Ran into an unparseable point.
ysr@345 679 return cur;
ysr@345 680 };
ysr@345 681 // Otherwise:
ysr@345 682 next = (cur + obj->size());
ysr@345 683 if (!g1h->is_obj_dead(obj)) {
ysr@345 684 if (next < mr.end()) {
ysr@345 685 obj->oop_iterate(cl);
ysr@345 686 } else {
ysr@345 687 // this obj spans the boundary. If it's an array, stop at the
ysr@345 688 // boundary.
ysr@345 689 if (obj->is_objArray()) {
ysr@345 690 obj->oop_iterate(cl, mr);
ysr@345 691 } else {
ysr@345 692 obj->oop_iterate(cl);
ysr@345 693 }
ysr@345 694 }
ysr@345 695 }
ysr@345 696 cur = next;
ysr@345 697 }
ysr@345 698 return NULL;
ysr@345 699 }
ysr@345 700
ysr@345 701 void HeapRegion::print() const { print_on(gclog_or_tty); }
ysr@345 702 void HeapRegion::print_on(outputStream* st) const {
ysr@345 703 if (isHumongous()) {
ysr@345 704 if (startsHumongous())
ysr@345 705 st->print(" HS");
ysr@345 706 else
ysr@345 707 st->print(" HC");
ysr@345 708 } else {
ysr@345 709 st->print(" ");
ysr@345 710 }
ysr@345 711 if (in_collection_set())
ysr@345 712 st->print(" CS");
ysr@345 713 else if (is_gc_alloc_region())
ysr@345 714 st->print(" A ");
ysr@345 715 else
ysr@345 716 st->print(" ");
ysr@345 717 if (is_young())
ysr@345 718 st->print(is_scan_only() ? " SO" : (is_survivor() ? " SU" : " Y "));
ysr@345 719 else
ysr@345 720 st->print(" ");
ysr@345 721 if (is_empty())
ysr@345 722 st->print(" F");
ysr@345 723 else
ysr@345 724 st->print(" ");
ysr@345 725 st->print(" %d", _gc_time_stamp);
ysr@345 726 G1OffsetTableContigSpace::print_on(st);
ysr@345 727 }
ysr@345 728
tonyp@860 729 void HeapRegion::verify(bool allow_dirty) const {
tonyp@860 730 verify(allow_dirty, /* use_prev_marking */ true);
tonyp@860 731 }
tonyp@860 732
ysr@345 733 #define OBJ_SAMPLE_INTERVAL 0
ysr@345 734 #define BLOCK_SAMPLE_INTERVAL 100
ysr@345 735
ysr@345 736 // This really ought to be commoned up into OffsetTableContigSpace somehow.
ysr@345 737 // We would need a mechanism to make that code skip dead objects.
ysr@345 738
tonyp@860 739 void HeapRegion::verify(bool allow_dirty, bool use_prev_marking) const {
ysr@345 740 G1CollectedHeap* g1 = G1CollectedHeap::heap();
ysr@345 741 HeapWord* p = bottom();
ysr@345 742 HeapWord* prev_p = NULL;
ysr@345 743 int objs = 0;
ysr@345 744 int blocks = 0;
tonyp@860 745 VerifyLiveClosure vl_cl(g1, use_prev_marking);
ysr@345 746 while (p < top()) {
ysr@345 747 size_t size = oop(p)->size();
ysr@345 748 if (blocks == BLOCK_SAMPLE_INTERVAL) {
ysr@345 749 guarantee(p == block_start_const(p + (size/2)),
ysr@345 750 "check offset computation");
ysr@345 751 blocks = 0;
ysr@345 752 } else {
ysr@345 753 blocks++;
ysr@345 754 }
ysr@345 755 if (objs == OBJ_SAMPLE_INTERVAL) {
ysr@345 756 oop obj = oop(p);
tonyp@860 757 if (!g1->is_obj_dead_cond(obj, this, use_prev_marking)) {
ysr@345 758 obj->verify();
ysr@345 759 vl_cl.set_containing_obj(obj);
ysr@345 760 obj->oop_iterate(&vl_cl);
ysr@345 761 if (G1MaxVerifyFailures >= 0
ysr@345 762 && vl_cl.n_failures() >= G1MaxVerifyFailures) break;
ysr@345 763 }
ysr@345 764 objs = 0;
ysr@345 765 } else {
ysr@345 766 objs++;
ysr@345 767 }
ysr@345 768 prev_p = p;
ysr@345 769 p += size;
ysr@345 770 }
ysr@345 771 HeapWord* rend = end();
ysr@345 772 HeapWord* rtop = top();
ysr@345 773 if (rtop < rend) {
ysr@345 774 guarantee(block_start_const(rtop + (rend - rtop) / 2) == rtop,
ysr@345 775 "check offset computation");
ysr@345 776 }
ysr@345 777 if (vl_cl.failures()) {
ysr@345 778 gclog_or_tty->print_cr("Heap:");
tonyp@887 779 G1CollectedHeap::heap()->print_on(gclog_or_tty, true /* extended */);
ysr@345 780 gclog_or_tty->print_cr("");
ysr@345 781 }
johnc@791 782 if (VerifyDuringGC &&
ysr@345 783 G1VerifyConcMarkPrintReachable &&
ysr@345 784 vl_cl.failures()) {
ysr@345 785 g1->concurrent_mark()->print_prev_bitmap_reachable();
ysr@345 786 }
tonyp@785 787 guarantee(!vl_cl.failures(), "region verification failed");
ysr@345 788 guarantee(p == top(), "end of last object must match end of space");
ysr@345 789 }
ysr@345 790
ysr@345 791 // G1OffsetTableContigSpace code; copied from space.cpp. Hope this can go
ysr@345 792 // away eventually.
ysr@345 793
tonyp@359 794 void G1OffsetTableContigSpace::initialize(MemRegion mr, bool clear_space, bool mangle_space) {
ysr@345 795 // false ==> we'll do the clearing if there's clearing to be done.
tonyp@359 796 ContiguousSpace::initialize(mr, false, mangle_space);
ysr@345 797 _offsets.zero_bottom_entry();
ysr@345 798 _offsets.initialize_threshold();
tonyp@359 799 if (clear_space) clear(mangle_space);
ysr@345 800 }
ysr@345 801
tonyp@359 802 void G1OffsetTableContigSpace::clear(bool mangle_space) {
tonyp@359 803 ContiguousSpace::clear(mangle_space);
ysr@345 804 _offsets.zero_bottom_entry();
ysr@345 805 _offsets.initialize_threshold();
ysr@345 806 }
ysr@345 807
ysr@345 808 void G1OffsetTableContigSpace::set_bottom(HeapWord* new_bottom) {
ysr@345 809 Space::set_bottom(new_bottom);
ysr@345 810 _offsets.set_bottom(new_bottom);
ysr@345 811 }
ysr@345 812
ysr@345 813 void G1OffsetTableContigSpace::set_end(HeapWord* new_end) {
ysr@345 814 Space::set_end(new_end);
ysr@345 815 _offsets.resize(new_end - bottom());
ysr@345 816 }
ysr@345 817
ysr@345 818 void G1OffsetTableContigSpace::print() const {
ysr@345 819 print_short();
ysr@345 820 gclog_or_tty->print_cr(" [" INTPTR_FORMAT ", " INTPTR_FORMAT ", "
ysr@345 821 INTPTR_FORMAT ", " INTPTR_FORMAT ")",
ysr@345 822 bottom(), top(), _offsets.threshold(), end());
ysr@345 823 }
ysr@345 824
ysr@345 825 HeapWord* G1OffsetTableContigSpace::initialize_threshold() {
ysr@345 826 return _offsets.initialize_threshold();
ysr@345 827 }
ysr@345 828
ysr@345 829 HeapWord* G1OffsetTableContigSpace::cross_threshold(HeapWord* start,
ysr@345 830 HeapWord* end) {
ysr@345 831 _offsets.alloc_block(start, end);
ysr@345 832 return _offsets.threshold();
ysr@345 833 }
ysr@345 834
ysr@345 835 HeapWord* G1OffsetTableContigSpace::saved_mark_word() const {
ysr@345 836 G1CollectedHeap* g1h = G1CollectedHeap::heap();
ysr@345 837 assert( _gc_time_stamp <= g1h->get_gc_time_stamp(), "invariant" );
ysr@345 838 if (_gc_time_stamp < g1h->get_gc_time_stamp())
ysr@345 839 return top();
ysr@345 840 else
ysr@345 841 return ContiguousSpace::saved_mark_word();
ysr@345 842 }
ysr@345 843
ysr@345 844 void G1OffsetTableContigSpace::set_saved_mark() {
ysr@345 845 G1CollectedHeap* g1h = G1CollectedHeap::heap();
ysr@345 846 unsigned curr_gc_time_stamp = g1h->get_gc_time_stamp();
ysr@345 847
ysr@345 848 if (_gc_time_stamp < curr_gc_time_stamp) {
ysr@345 849 // The order of these is important, as another thread might be
ysr@345 850 // about to start scanning this region. If it does so after
ysr@345 851 // set_saved_mark and before _gc_time_stamp = ..., then the latter
ysr@345 852 // will be false, and it will pick up top() as the high water mark
ysr@345 853 // of region. If it does so after _gc_time_stamp = ..., then it
ysr@345 854 // will pick up the right saved_mark_word() as the high water mark
ysr@345 855 // of the region. Either way, the behaviour will be correct.
ysr@345 856 ContiguousSpace::set_saved_mark();
ysr@896 857 OrderAccess::storestore();
iveresov@356 858 _gc_time_stamp = curr_gc_time_stamp;
ysr@896 859 // The following fence is to force a flush of the writes above, but
ysr@896 860 // is strictly not needed because when an allocating worker thread
ysr@896 861 // calls set_saved_mark() it does so under the ParGCRareEvent_lock;
ysr@896 862 // when the lock is released, the write will be flushed.
ysr@896 863 // OrderAccess::fence();
ysr@345 864 }
ysr@345 865 }
ysr@345 866
ysr@345 867 G1OffsetTableContigSpace::
ysr@345 868 G1OffsetTableContigSpace(G1BlockOffsetSharedArray* sharedOffsetArray,
ysr@345 869 MemRegion mr, bool is_zeroed) :
ysr@345 870 _offsets(sharedOffsetArray, mr),
ysr@345 871 _par_alloc_lock(Mutex::leaf, "OffsetTableContigSpace par alloc lock", true),
ysr@345 872 _gc_time_stamp(0)
ysr@345 873 {
ysr@345 874 _offsets.set_space(this);
tonyp@359 875 initialize(mr, !is_zeroed, SpaceDecorator::Mangle);
ysr@345 876 }
ysr@345 877
ysr@345 878 size_t RegionList::length() {
ysr@345 879 size_t len = 0;
ysr@345 880 HeapRegion* cur = hd();
ysr@345 881 DEBUG_ONLY(HeapRegion* last = NULL);
ysr@345 882 while (cur != NULL) {
ysr@345 883 len++;
ysr@345 884 DEBUG_ONLY(last = cur);
ysr@345 885 cur = get_next(cur);
ysr@345 886 }
ysr@345 887 assert(last == tl(), "Invariant");
ysr@345 888 return len;
ysr@345 889 }
ysr@345 890
ysr@345 891 void RegionList::insert_before_head(HeapRegion* r) {
ysr@345 892 assert(well_formed(), "Inv");
ysr@345 893 set_next(r, hd());
ysr@345 894 _hd = r;
ysr@345 895 _sz++;
ysr@345 896 if (tl() == NULL) _tl = r;
ysr@345 897 assert(well_formed(), "Inv");
ysr@345 898 }
ysr@345 899
ysr@345 900 void RegionList::prepend_list(RegionList* new_list) {
ysr@345 901 assert(well_formed(), "Precondition");
ysr@345 902 assert(new_list->well_formed(), "Precondition");
ysr@345 903 HeapRegion* new_tl = new_list->tl();
ysr@345 904 if (new_tl != NULL) {
ysr@345 905 set_next(new_tl, hd());
ysr@345 906 _hd = new_list->hd();
ysr@345 907 _sz += new_list->sz();
ysr@345 908 if (tl() == NULL) _tl = new_list->tl();
ysr@345 909 } else {
ysr@345 910 assert(new_list->hd() == NULL && new_list->sz() == 0, "Inv");
ysr@345 911 }
ysr@345 912 assert(well_formed(), "Inv");
ysr@345 913 }
ysr@345 914
ysr@345 915 void RegionList::delete_after(HeapRegion* r) {
ysr@345 916 assert(well_formed(), "Precondition");
ysr@345 917 HeapRegion* next = get_next(r);
ysr@345 918 assert(r != NULL, "Precondition");
ysr@345 919 HeapRegion* next_tl = get_next(next);
ysr@345 920 set_next(r, next_tl);
ysr@345 921 dec_sz();
ysr@345 922 if (next == tl()) {
ysr@345 923 assert(next_tl == NULL, "Inv");
ysr@345 924 _tl = r;
ysr@345 925 }
ysr@345 926 assert(well_formed(), "Inv");
ysr@345 927 }
ysr@345 928
ysr@345 929 HeapRegion* RegionList::pop() {
ysr@345 930 assert(well_formed(), "Inv");
ysr@345 931 HeapRegion* res = hd();
ysr@345 932 if (res != NULL) {
ysr@345 933 _hd = get_next(res);
ysr@345 934 _sz--;
ysr@345 935 set_next(res, NULL);
ysr@345 936 if (sz() == 0) _tl = NULL;
ysr@345 937 }
ysr@345 938 assert(well_formed(), "Inv");
ysr@345 939 return res;
ysr@345 940 }