Sat, 01 Sep 2012 13:25:18 -0400
6964458: Reimplement class meta-data storage to use native memory
Summary: Remove PermGen, allocate meta-data in metaspace linked to class loaders, rewrite GC walking, rewrite and rename metadata to be C++ classes
Reviewed-by: jmasa, stefank, never, coleenp, kvn, brutisso, mgerdin, dholmes, jrose, twisti, roland
Contributed-by: jmasa <jon.masamitsu@oracle.com>, stefank <stefan.karlsson@oracle.com>, mgerdin <mikael.gerdin@oracle.com>, never <tom.rodriguez@oracle.com>
1 /*
2 * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.
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 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
25 #include "precompiled.hpp"
26 #include "gc_implementation/shared/spaceDecorator.hpp"
27 #include "gc_interface/collectedHeap.inline.hpp"
28 #include "memory/allocation.inline.hpp"
29 #include "memory/blockOffsetTable.inline.hpp"
30 #include "memory/cardTableRS.hpp"
31 #include "memory/gcLocker.inline.hpp"
32 #include "memory/genCollectedHeap.hpp"
33 #include "memory/genMarkSweep.hpp"
34 #include "memory/genOopClosures.hpp"
35 #include "memory/genOopClosures.inline.hpp"
36 #include "memory/generation.hpp"
37 #include "memory/generation.inline.hpp"
38 #include "memory/space.inline.hpp"
39 #include "oops/oop.inline.hpp"
40 #include "runtime/java.hpp"
41 #include "utilities/copy.hpp"
42 #include "utilities/events.hpp"
44 Generation::Generation(ReservedSpace rs, size_t initial_size, int level) :
45 _level(level),
46 _ref_processor(NULL) {
47 if (!_virtual_space.initialize(rs, initial_size)) {
48 vm_exit_during_initialization("Could not reserve enough space for "
49 "object heap");
50 }
51 // Mangle all of the the initial generation.
52 if (ZapUnusedHeapArea) {
53 MemRegion mangle_region((HeapWord*)_virtual_space.low(),
54 (HeapWord*)_virtual_space.high());
55 SpaceMangler::mangle_region(mangle_region);
56 }
57 _reserved = MemRegion((HeapWord*)_virtual_space.low_boundary(),
58 (HeapWord*)_virtual_space.high_boundary());
59 }
61 GenerationSpec* Generation::spec() {
62 GenCollectedHeap* gch = GenCollectedHeap::heap();
63 assert(0 <= level() && level() < gch->_n_gens, "Bad gen level");
64 return gch->_gen_specs[level()];
65 }
67 size_t Generation::max_capacity() const {
68 return reserved().byte_size();
69 }
71 void Generation::print_heap_change(size_t prev_used) const {
72 if (PrintGCDetails && Verbose) {
73 gclog_or_tty->print(" " SIZE_FORMAT
74 "->" SIZE_FORMAT
75 "(" SIZE_FORMAT ")",
76 prev_used, used(), capacity());
77 } else {
78 gclog_or_tty->print(" " SIZE_FORMAT "K"
79 "->" SIZE_FORMAT "K"
80 "(" SIZE_FORMAT "K)",
81 prev_used / K, used() / K, capacity() / K);
82 }
83 }
85 // By default we get a single threaded default reference processor;
86 // generations needing multi-threaded refs processing or discovery override this method.
87 void Generation::ref_processor_init() {
88 assert(_ref_processor == NULL, "a reference processor already exists");
89 assert(!_reserved.is_empty(), "empty generation?");
90 _ref_processor = new ReferenceProcessor(_reserved); // a vanilla reference processor
91 if (_ref_processor == NULL) {
92 vm_exit_during_initialization("Could not allocate ReferenceProcessor object");
93 }
94 }
96 void Generation::print() const { print_on(tty); }
98 void Generation::print_on(outputStream* st) const {
99 st->print(" %-20s", name());
100 st->print(" total " SIZE_FORMAT "K, used " SIZE_FORMAT "K",
101 capacity()/K, used()/K);
102 st->print_cr(" [" INTPTR_FORMAT ", " INTPTR_FORMAT ", " INTPTR_FORMAT ")",
103 _virtual_space.low_boundary(),
104 _virtual_space.high(),
105 _virtual_space.high_boundary());
106 }
108 void Generation::print_summary_info() { print_summary_info_on(tty); }
110 void Generation::print_summary_info_on(outputStream* st) {
111 StatRecord* sr = stat_record();
112 double time = sr->accumulated_time.seconds();
113 st->print_cr("[Accumulated GC generation %d time %3.7f secs, "
114 "%d GC's, avg GC time %3.7f]",
115 level(), time, sr->invocations,
116 sr->invocations > 0 ? time / sr->invocations : 0.0);
117 }
119 // Utility iterator classes
121 class GenerationIsInReservedClosure : public SpaceClosure {
122 public:
123 const void* _p;
124 Space* sp;
125 virtual void do_space(Space* s) {
126 if (sp == NULL) {
127 if (s->is_in_reserved(_p)) sp = s;
128 }
129 }
130 GenerationIsInReservedClosure(const void* p) : _p(p), sp(NULL) {}
131 };
133 class GenerationIsInClosure : public SpaceClosure {
134 public:
135 const void* _p;
136 Space* sp;
137 virtual void do_space(Space* s) {
138 if (sp == NULL) {
139 if (s->is_in(_p)) sp = s;
140 }
141 }
142 GenerationIsInClosure(const void* p) : _p(p), sp(NULL) {}
143 };
145 bool Generation::is_in(const void* p) const {
146 GenerationIsInClosure blk(p);
147 ((Generation*)this)->space_iterate(&blk);
148 return blk.sp != NULL;
149 }
151 DefNewGeneration* Generation::as_DefNewGeneration() {
152 assert((kind() == Generation::DefNew) ||
153 (kind() == Generation::ParNew) ||
154 (kind() == Generation::ASParNew),
155 "Wrong youngest generation type");
156 return (DefNewGeneration*) this;
157 }
159 Generation* Generation::next_gen() const {
160 GenCollectedHeap* gch = GenCollectedHeap::heap();
161 int next = level() + 1;
162 if (next < gch->_n_gens) {
163 return gch->_gens[next];
164 } else {
165 return NULL;
166 }
167 }
169 size_t Generation::max_contiguous_available() const {
170 // The largest number of contiguous free words in this or any higher generation.
171 size_t max = 0;
172 for (const Generation* gen = this; gen != NULL; gen = gen->next_gen()) {
173 size_t avail = gen->contiguous_available();
174 if (avail > max) {
175 max = avail;
176 }
177 }
178 return max;
179 }
181 bool Generation::promotion_attempt_is_safe(size_t max_promotion_in_bytes) const {
182 size_t available = max_contiguous_available();
183 bool res = (available >= max_promotion_in_bytes);
184 if (PrintGC && Verbose) {
185 gclog_or_tty->print_cr(
186 "Generation: promo attempt is%s safe: available("SIZE_FORMAT") %s max_promo("SIZE_FORMAT")",
187 res? "":" not", available, res? ">=":"<",
188 max_promotion_in_bytes);
189 }
190 return res;
191 }
193 // Ignores "ref" and calls allocate().
194 oop Generation::promote(oop obj, size_t obj_size) {
195 assert(obj_size == (size_t)obj->size(), "bad obj_size passed in");
197 #ifndef PRODUCT
198 if (Universe::heap()->promotion_should_fail()) {
199 return NULL;
200 }
201 #endif // #ifndef PRODUCT
203 HeapWord* result = allocate(obj_size, false);
204 if (result != NULL) {
205 Copy::aligned_disjoint_words((HeapWord*)obj, result, obj_size);
206 return oop(result);
207 } else {
208 GenCollectedHeap* gch = GenCollectedHeap::heap();
209 return gch->handle_failed_promotion(this, obj, obj_size);
210 }
211 }
213 oop Generation::par_promote(int thread_num,
214 oop obj, markOop m, size_t word_sz) {
215 // Could do a bad general impl here that gets a lock. But no.
216 ShouldNotCallThis();
217 return NULL;
218 }
220 void Generation::par_promote_alloc_undo(int thread_num,
221 HeapWord* obj, size_t word_sz) {
222 // Could do a bad general impl here that gets a lock. But no.
223 guarantee(false, "No good general implementation.");
224 }
226 Space* Generation::space_containing(const void* p) const {
227 GenerationIsInReservedClosure blk(p);
228 // Cast away const
229 ((Generation*)this)->space_iterate(&blk);
230 return blk.sp;
231 }
233 // Some of these are mediocre general implementations. Should be
234 // overridden to get better performance.
236 class GenerationBlockStartClosure : public SpaceClosure {
237 public:
238 const void* _p;
239 HeapWord* _start;
240 virtual void do_space(Space* s) {
241 if (_start == NULL && s->is_in_reserved(_p)) {
242 _start = s->block_start(_p);
243 }
244 }
245 GenerationBlockStartClosure(const void* p) { _p = p; _start = NULL; }
246 };
248 HeapWord* Generation::block_start(const void* p) const {
249 GenerationBlockStartClosure blk(p);
250 // Cast away const
251 ((Generation*)this)->space_iterate(&blk);
252 return blk._start;
253 }
255 class GenerationBlockSizeClosure : public SpaceClosure {
256 public:
257 const HeapWord* _p;
258 size_t size;
259 virtual void do_space(Space* s) {
260 if (size == 0 && s->is_in_reserved(_p)) {
261 size = s->block_size(_p);
262 }
263 }
264 GenerationBlockSizeClosure(const HeapWord* p) { _p = p; size = 0; }
265 };
267 size_t Generation::block_size(const HeapWord* p) const {
268 GenerationBlockSizeClosure blk(p);
269 // Cast away const
270 ((Generation*)this)->space_iterate(&blk);
271 assert(blk.size > 0, "seems reasonable");
272 return blk.size;
273 }
275 class GenerationBlockIsObjClosure : public SpaceClosure {
276 public:
277 const HeapWord* _p;
278 bool is_obj;
279 virtual void do_space(Space* s) {
280 if (!is_obj && s->is_in_reserved(_p)) {
281 is_obj |= s->block_is_obj(_p);
282 }
283 }
284 GenerationBlockIsObjClosure(const HeapWord* p) { _p = p; is_obj = false; }
285 };
287 bool Generation::block_is_obj(const HeapWord* p) const {
288 GenerationBlockIsObjClosure blk(p);
289 // Cast away const
290 ((Generation*)this)->space_iterate(&blk);
291 return blk.is_obj;
292 }
294 class GenerationOopIterateClosure : public SpaceClosure {
295 public:
296 ExtendedOopClosure* cl;
297 MemRegion mr;
298 virtual void do_space(Space* s) {
299 s->oop_iterate(mr, cl);
300 }
301 GenerationOopIterateClosure(ExtendedOopClosure* _cl, MemRegion _mr) :
302 cl(_cl), mr(_mr) {}
303 };
305 void Generation::oop_iterate(ExtendedOopClosure* cl) {
306 GenerationOopIterateClosure blk(cl, _reserved);
307 space_iterate(&blk);
308 }
310 void Generation::oop_iterate(MemRegion mr, ExtendedOopClosure* cl) {
311 GenerationOopIterateClosure blk(cl, mr);
312 space_iterate(&blk);
313 }
315 void Generation::younger_refs_in_space_iterate(Space* sp,
316 OopsInGenClosure* cl) {
317 GenRemSet* rs = SharedHeap::heap()->rem_set();
318 rs->younger_refs_in_space_iterate(sp, cl);
319 }
321 class GenerationObjIterateClosure : public SpaceClosure {
322 private:
323 ObjectClosure* _cl;
324 public:
325 virtual void do_space(Space* s) {
326 s->object_iterate(_cl);
327 }
328 GenerationObjIterateClosure(ObjectClosure* cl) : _cl(cl) {}
329 };
331 void Generation::object_iterate(ObjectClosure* cl) {
332 GenerationObjIterateClosure blk(cl);
333 space_iterate(&blk);
334 }
336 class GenerationSafeObjIterateClosure : public SpaceClosure {
337 private:
338 ObjectClosure* _cl;
339 public:
340 virtual void do_space(Space* s) {
341 s->safe_object_iterate(_cl);
342 }
343 GenerationSafeObjIterateClosure(ObjectClosure* cl) : _cl(cl) {}
344 };
346 void Generation::safe_object_iterate(ObjectClosure* cl) {
347 GenerationSafeObjIterateClosure blk(cl);
348 space_iterate(&blk);
349 }
351 void Generation::prepare_for_compaction(CompactPoint* cp) {
352 // Generic implementation, can be specialized
353 CompactibleSpace* space = first_compaction_space();
354 while (space != NULL) {
355 space->prepare_for_compaction(cp);
356 space = space->next_compaction_space();
357 }
358 }
360 class AdjustPointersClosure: public SpaceClosure {
361 public:
362 void do_space(Space* sp) {
363 sp->adjust_pointers();
364 }
365 };
367 void Generation::adjust_pointers() {
368 // Note that this is done over all spaces, not just the compactible
369 // ones.
370 AdjustPointersClosure blk;
371 space_iterate(&blk, true);
372 }
374 void Generation::compact() {
375 CompactibleSpace* sp = first_compaction_space();
376 while (sp != NULL) {
377 sp->compact();
378 sp = sp->next_compaction_space();
379 }
380 }
382 CardGeneration::CardGeneration(ReservedSpace rs, size_t initial_byte_size,
383 int level,
384 GenRemSet* remset) :
385 Generation(rs, initial_byte_size, level), _rs(remset)
386 {
387 HeapWord* start = (HeapWord*)rs.base();
388 size_t reserved_byte_size = rs.size();
389 assert((uintptr_t(start) & 3) == 0, "bad alignment");
390 assert((reserved_byte_size & 3) == 0, "bad alignment");
391 MemRegion reserved_mr(start, heap_word_size(reserved_byte_size));
392 _bts = new BlockOffsetSharedArray(reserved_mr,
393 heap_word_size(initial_byte_size));
394 MemRegion committed_mr(start, heap_word_size(initial_byte_size));
395 _rs->resize_covered_region(committed_mr);
396 if (_bts == NULL)
397 vm_exit_during_initialization("Could not allocate a BlockOffsetArray");
399 // Verify that the start and end of this generation is the start of a card.
400 // If this wasn't true, a single card could span more than on generation,
401 // which would cause problems when we commit/uncommit memory, and when we
402 // clear and dirty cards.
403 guarantee(_rs->is_aligned(reserved_mr.start()), "generation must be card aligned");
404 if (reserved_mr.end() != Universe::heap()->reserved_region().end()) {
405 // Don't check at the very end of the heap as we'll assert that we're probing off
406 // the end if we try.
407 guarantee(_rs->is_aligned(reserved_mr.end()), "generation must be card aligned");
408 }
409 }
411 bool CardGeneration::expand(size_t bytes, size_t expand_bytes) {
412 assert_locked_or_safepoint(Heap_lock);
413 if (bytes == 0) {
414 return true; // That's what grow_by(0) would return
415 }
416 size_t aligned_bytes = ReservedSpace::page_align_size_up(bytes);
417 if (aligned_bytes == 0){
418 // The alignment caused the number of bytes to wrap. An expand_by(0) will
419 // return true with the implication that an expansion was done when it
420 // was not. A call to expand implies a best effort to expand by "bytes"
421 // but not a guarantee. Align down to give a best effort. This is likely
422 // the most that the generation can expand since it has some capacity to
423 // start with.
424 aligned_bytes = ReservedSpace::page_align_size_down(bytes);
425 }
426 size_t aligned_expand_bytes = ReservedSpace::page_align_size_up(expand_bytes);
427 bool success = false;
428 if (aligned_expand_bytes > aligned_bytes) {
429 success = grow_by(aligned_expand_bytes);
430 }
431 if (!success) {
432 success = grow_by(aligned_bytes);
433 }
434 if (!success) {
435 success = grow_to_reserved();
436 }
437 if (PrintGC && Verbose) {
438 if (success && GC_locker::is_active_and_needs_gc()) {
439 gclog_or_tty->print_cr("Garbage collection disabled, expanded heap instead");
440 }
441 }
443 return success;
444 }
447 // No young generation references, clear this generation's cards.
448 void CardGeneration::clear_remembered_set() {
449 _rs->clear(reserved());
450 }
453 // Objects in this generation may have moved, invalidate this
454 // generation's cards.
455 void CardGeneration::invalidate_remembered_set() {
456 _rs->invalidate(used_region());
457 }
460 // Currently nothing to do.
461 void CardGeneration::prepare_for_verify() {}
464 void OneContigSpaceCardGeneration::collect(bool full,
465 bool clear_all_soft_refs,
466 size_t size,
467 bool is_tlab) {
468 SpecializationStats::clear();
469 // Temporarily expand the span of our ref processor, so
470 // refs discovery is over the entire heap, not just this generation
471 ReferenceProcessorSpanMutator
472 x(ref_processor(), GenCollectedHeap::heap()->reserved_region());
473 GenMarkSweep::invoke_at_safepoint(_level, ref_processor(), clear_all_soft_refs);
474 SpecializationStats::print();
475 }
477 HeapWord*
478 OneContigSpaceCardGeneration::expand_and_allocate(size_t word_size,
479 bool is_tlab,
480 bool parallel) {
481 assert(!is_tlab, "OneContigSpaceCardGeneration does not support TLAB allocation");
482 if (parallel) {
483 MutexLocker x(ParGCRareEvent_lock);
484 HeapWord* result = NULL;
485 size_t byte_size = word_size * HeapWordSize;
486 while (true) {
487 expand(byte_size, _min_heap_delta_bytes);
488 if (GCExpandToAllocateDelayMillis > 0) {
489 os::sleep(Thread::current(), GCExpandToAllocateDelayMillis, false);
490 }
491 result = _the_space->par_allocate(word_size);
492 if ( result != NULL) {
493 return result;
494 } else {
495 // If there's not enough expansion space available, give up.
496 if (_virtual_space.uncommitted_size() < byte_size) {
497 return NULL;
498 }
499 // else try again
500 }
501 }
502 } else {
503 expand(word_size*HeapWordSize, _min_heap_delta_bytes);
504 return _the_space->allocate(word_size);
505 }
506 }
508 bool OneContigSpaceCardGeneration::expand(size_t bytes, size_t expand_bytes) {
509 GCMutexLocker x(ExpandHeap_lock);
510 return CardGeneration::expand(bytes, expand_bytes);
511 }
514 void OneContigSpaceCardGeneration::shrink(size_t bytes) {
515 assert_locked_or_safepoint(ExpandHeap_lock);
516 size_t size = ReservedSpace::page_align_size_down(bytes);
517 if (size > 0) {
518 shrink_by(size);
519 }
520 }
523 size_t OneContigSpaceCardGeneration::capacity() const {
524 return _the_space->capacity();
525 }
528 size_t OneContigSpaceCardGeneration::used() const {
529 return _the_space->used();
530 }
533 size_t OneContigSpaceCardGeneration::free() const {
534 return _the_space->free();
535 }
537 MemRegion OneContigSpaceCardGeneration::used_region() const {
538 return the_space()->used_region();
539 }
541 size_t OneContigSpaceCardGeneration::unsafe_max_alloc_nogc() const {
542 return _the_space->free();
543 }
545 size_t OneContigSpaceCardGeneration::contiguous_available() const {
546 return _the_space->free() + _virtual_space.uncommitted_size();
547 }
549 bool OneContigSpaceCardGeneration::grow_by(size_t bytes) {
550 assert_locked_or_safepoint(ExpandHeap_lock);
551 bool result = _virtual_space.expand_by(bytes);
552 if (result) {
553 size_t new_word_size =
554 heap_word_size(_virtual_space.committed_size());
555 MemRegion mr(_the_space->bottom(), new_word_size);
556 // Expand card table
557 Universe::heap()->barrier_set()->resize_covered_region(mr);
558 // Expand shared block offset array
559 _bts->resize(new_word_size);
561 // Fix for bug #4668531
562 if (ZapUnusedHeapArea) {
563 MemRegion mangle_region(_the_space->end(),
564 (HeapWord*)_virtual_space.high());
565 SpaceMangler::mangle_region(mangle_region);
566 }
568 // Expand space -- also expands space's BOT
569 // (which uses (part of) shared array above)
570 _the_space->set_end((HeapWord*)_virtual_space.high());
572 // update the space and generation capacity counters
573 update_counters();
575 if (Verbose && PrintGC) {
576 size_t new_mem_size = _virtual_space.committed_size();
577 size_t old_mem_size = new_mem_size - bytes;
578 gclog_or_tty->print_cr("Expanding %s from " SIZE_FORMAT "K by "
579 SIZE_FORMAT "K to " SIZE_FORMAT "K",
580 name(), old_mem_size/K, bytes/K, new_mem_size/K);
581 }
582 }
583 return result;
584 }
587 bool OneContigSpaceCardGeneration::grow_to_reserved() {
588 assert_locked_or_safepoint(ExpandHeap_lock);
589 bool success = true;
590 const size_t remaining_bytes = _virtual_space.uncommitted_size();
591 if (remaining_bytes > 0) {
592 success = grow_by(remaining_bytes);
593 DEBUG_ONLY(if (!success) warning("grow to reserved failed");)
594 }
595 return success;
596 }
598 void OneContigSpaceCardGeneration::shrink_by(size_t bytes) {
599 assert_locked_or_safepoint(ExpandHeap_lock);
600 // Shrink committed space
601 _virtual_space.shrink_by(bytes);
602 // Shrink space; this also shrinks the space's BOT
603 _the_space->set_end((HeapWord*) _virtual_space.high());
604 size_t new_word_size = heap_word_size(_the_space->capacity());
605 // Shrink the shared block offset array
606 _bts->resize(new_word_size);
607 MemRegion mr(_the_space->bottom(), new_word_size);
608 // Shrink the card table
609 Universe::heap()->barrier_set()->resize_covered_region(mr);
611 if (Verbose && PrintGC) {
612 size_t new_mem_size = _virtual_space.committed_size();
613 size_t old_mem_size = new_mem_size + bytes;
614 gclog_or_tty->print_cr("Shrinking %s from " SIZE_FORMAT "K to " SIZE_FORMAT "K",
615 name(), old_mem_size/K, new_mem_size/K);
616 }
617 }
619 // Currently nothing to do.
620 void OneContigSpaceCardGeneration::prepare_for_verify() {}
623 // Override for a card-table generation with one contiguous
624 // space. NOTE: For reasons that are lost in the fog of history,
625 // this code is used when you iterate over perm gen objects,
626 // even when one uses CDS, where the perm gen has a couple of
627 // other spaces; this is because CompactingPermGenGen derives
628 // from OneContigSpaceCardGeneration. This should be cleaned up,
629 // see CR 6897789..
630 void OneContigSpaceCardGeneration::object_iterate(ObjectClosure* blk) {
631 _the_space->object_iterate(blk);
632 }
634 void OneContigSpaceCardGeneration::space_iterate(SpaceClosure* blk,
635 bool usedOnly) {
636 blk->do_space(_the_space);
637 }
639 void OneContigSpaceCardGeneration::object_iterate_since_last_GC(ObjectClosure* blk) {
640 // Deal with delayed initialization of _the_space,
641 // and lack of initialization of _last_gc.
642 if (_last_gc.space() == NULL) {
643 assert(the_space() != NULL, "shouldn't be NULL");
644 _last_gc = the_space()->bottom_mark();
645 }
646 the_space()->object_iterate_from(_last_gc, blk);
647 }
649 void OneContigSpaceCardGeneration::younger_refs_iterate(OopsInGenClosure* blk) {
650 blk->set_generation(this);
651 younger_refs_in_space_iterate(_the_space, blk);
652 blk->reset_generation();
653 }
655 void OneContigSpaceCardGeneration::save_marks() {
656 _the_space->set_saved_mark();
657 }
660 void OneContigSpaceCardGeneration::reset_saved_marks() {
661 _the_space->reset_saved_mark();
662 }
665 bool OneContigSpaceCardGeneration::no_allocs_since_save_marks() {
666 return _the_space->saved_mark_at_top();
667 }
669 #define OneContig_SINCE_SAVE_MARKS_ITERATE_DEFN(OopClosureType, nv_suffix) \
670 \
671 void OneContigSpaceCardGeneration:: \
672 oop_since_save_marks_iterate##nv_suffix(OopClosureType* blk) { \
673 blk->set_generation(this); \
674 _the_space->oop_since_save_marks_iterate##nv_suffix(blk); \
675 blk->reset_generation(); \
676 save_marks(); \
677 }
679 ALL_SINCE_SAVE_MARKS_CLOSURES(OneContig_SINCE_SAVE_MARKS_ITERATE_DEFN)
681 #undef OneContig_SINCE_SAVE_MARKS_ITERATE_DEFN
684 void OneContigSpaceCardGeneration::gc_epilogue(bool full) {
685 _last_gc = WaterMark(the_space(), the_space()->top());
687 // update the generation and space performance counters
688 update_counters();
689 if (ZapUnusedHeapArea) {
690 the_space()->check_mangled_unused_area_complete();
691 }
692 }
694 void OneContigSpaceCardGeneration::record_spaces_top() {
695 assert(ZapUnusedHeapArea, "Not mangling unused space");
696 the_space()->set_top_for_allocations();
697 }
699 void OneContigSpaceCardGeneration::verify() {
700 the_space()->verify();
701 }
703 void OneContigSpaceCardGeneration::print_on(outputStream* st) const {
704 Generation::print_on(st);
705 st->print(" the");
706 the_space()->print_on(st);
707 }