| /* |
| * Copyright (c) 2001, 2011, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "gc_implementation/g1/g1BlockOffsetTable.inline.hpp" |
| #include "gc_implementation/g1/g1CollectedHeap.inline.hpp" |
| #include "gc_implementation/g1/g1OopClosures.inline.hpp" |
| #include "gc_implementation/g1/heapRegion.inline.hpp" |
| #include "gc_implementation/g1/heapRegionRemSet.hpp" |
| #include "gc_implementation/g1/heapRegionSeq.inline.hpp" |
| #include "memory/genOopClosures.inline.hpp" |
| #include "memory/iterator.hpp" |
| #include "oops/oop.inline.hpp" |
| |
| int HeapRegion::LogOfHRGrainBytes = 0; |
| int HeapRegion::LogOfHRGrainWords = 0; |
| int HeapRegion::GrainBytes = 0; |
| int HeapRegion::GrainWords = 0; |
| int HeapRegion::CardsPerRegion = 0; |
| |
| HeapRegionDCTOC::HeapRegionDCTOC(G1CollectedHeap* g1, |
| HeapRegion* hr, OopClosure* cl, |
| CardTableModRefBS::PrecisionStyle precision, |
| FilterKind fk) : |
| ContiguousSpaceDCTOC(hr, cl, precision, NULL), |
| _hr(hr), _fk(fk), _g1(g1) |
| {} |
| |
| FilterOutOfRegionClosure::FilterOutOfRegionClosure(HeapRegion* r, |
| OopClosure* oc) : |
| _r_bottom(r->bottom()), _r_end(r->end()), |
| _oc(oc), _out_of_region(0) |
| {} |
| |
| class VerifyLiveClosure: public OopClosure { |
| private: |
| G1CollectedHeap* _g1h; |
| CardTableModRefBS* _bs; |
| oop _containing_obj; |
| bool _failures; |
| int _n_failures; |
| bool _use_prev_marking; |
| public: |
| // use_prev_marking == true -> use "prev" marking information, |
| // use_prev_marking == false -> use "next" marking information |
| VerifyLiveClosure(G1CollectedHeap* g1h, bool use_prev_marking) : |
| _g1h(g1h), _bs(NULL), _containing_obj(NULL), |
| _failures(false), _n_failures(0), _use_prev_marking(use_prev_marking) |
| { |
| BarrierSet* bs = _g1h->barrier_set(); |
| if (bs->is_a(BarrierSet::CardTableModRef)) |
| _bs = (CardTableModRefBS*)bs; |
| } |
| |
| void set_containing_obj(oop obj) { |
| _containing_obj = obj; |
| } |
| |
| bool failures() { return _failures; } |
| int n_failures() { return _n_failures; } |
| |
| virtual void do_oop(narrowOop* p) { do_oop_work(p); } |
| virtual void do_oop( oop* p) { do_oop_work(p); } |
| |
| void print_object(outputStream* out, oop obj) { |
| #ifdef PRODUCT |
| klassOop k = obj->klass(); |
| const char* class_name = instanceKlass::cast(k)->external_name(); |
| out->print_cr("class name %s", class_name); |
| #else // PRODUCT |
| obj->print_on(out); |
| #endif // PRODUCT |
| } |
| |
| template <class T> void do_oop_work(T* p) { |
| assert(_containing_obj != NULL, "Precondition"); |
| assert(!_g1h->is_obj_dead_cond(_containing_obj, _use_prev_marking), |
| "Precondition"); |
| T heap_oop = oopDesc::load_heap_oop(p); |
| if (!oopDesc::is_null(heap_oop)) { |
| oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); |
| bool failed = false; |
| if (!_g1h->is_in_closed_subset(obj) || |
| _g1h->is_obj_dead_cond(obj, _use_prev_marking)) { |
| if (!_failures) { |
| gclog_or_tty->print_cr(""); |
| gclog_or_tty->print_cr("----------"); |
| } |
| if (!_g1h->is_in_closed_subset(obj)) { |
| HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p); |
| gclog_or_tty->print_cr("Field "PTR_FORMAT |
| " of live obj "PTR_FORMAT" in region " |
| "["PTR_FORMAT", "PTR_FORMAT")", |
| p, (void*) _containing_obj, |
| from->bottom(), from->end()); |
| print_object(gclog_or_tty, _containing_obj); |
| gclog_or_tty->print_cr("points to obj "PTR_FORMAT" not in the heap", |
| (void*) obj); |
| } else { |
| HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p); |
| HeapRegion* to = _g1h->heap_region_containing((HeapWord*)obj); |
| gclog_or_tty->print_cr("Field "PTR_FORMAT |
| " of live obj "PTR_FORMAT" in region " |
| "["PTR_FORMAT", "PTR_FORMAT")", |
| p, (void*) _containing_obj, |
| from->bottom(), from->end()); |
| print_object(gclog_or_tty, _containing_obj); |
| gclog_or_tty->print_cr("points to dead obj "PTR_FORMAT" in region " |
| "["PTR_FORMAT", "PTR_FORMAT")", |
| (void*) obj, to->bottom(), to->end()); |
| print_object(gclog_or_tty, obj); |
| } |
| gclog_or_tty->print_cr("----------"); |
| _failures = true; |
| failed = true; |
| _n_failures++; |
| } |
| |
| if (!_g1h->full_collection()) { |
| HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p); |
| HeapRegion* to = _g1h->heap_region_containing(obj); |
| if (from != NULL && to != NULL && |
| from != to && |
| !to->isHumongous()) { |
| jbyte cv_obj = *_bs->byte_for_const(_containing_obj); |
| jbyte cv_field = *_bs->byte_for_const(p); |
| const jbyte dirty = CardTableModRefBS::dirty_card_val(); |
| |
| bool is_bad = !(from->is_young() |
| || to->rem_set()->contains_reference(p) |
| || !G1HRRSFlushLogBuffersOnVerify && // buffers were not flushed |
| (_containing_obj->is_objArray() ? |
| cv_field == dirty |
| : cv_obj == dirty || cv_field == dirty)); |
| if (is_bad) { |
| if (!_failures) { |
| gclog_or_tty->print_cr(""); |
| gclog_or_tty->print_cr("----------"); |
| } |
| gclog_or_tty->print_cr("Missing rem set entry:"); |
| gclog_or_tty->print_cr("Field "PTR_FORMAT |
| " of obj "PTR_FORMAT |
| ", in region %d ["PTR_FORMAT |
| ", "PTR_FORMAT"),", |
| p, (void*) _containing_obj, |
| from->hrs_index(), |
| from->bottom(), |
| from->end()); |
| _containing_obj->print_on(gclog_or_tty); |
| gclog_or_tty->print_cr("points to obj "PTR_FORMAT |
| " in region %d ["PTR_FORMAT |
| ", "PTR_FORMAT").", |
| (void*) obj, to->hrs_index(), |
| to->bottom(), to->end()); |
| obj->print_on(gclog_or_tty); |
| gclog_or_tty->print_cr("Obj head CTE = %d, field CTE = %d.", |
| cv_obj, cv_field); |
| gclog_or_tty->print_cr("----------"); |
| _failures = true; |
| if (!failed) _n_failures++; |
| } |
| } |
| } |
| } |
| } |
| }; |
| |
| template<class ClosureType> |
| HeapWord* walk_mem_region_loop(ClosureType* cl, G1CollectedHeap* g1h, |
| HeapRegion* hr, |
| HeapWord* cur, HeapWord* top) { |
| oop cur_oop = oop(cur); |
| int oop_size = cur_oop->size(); |
| HeapWord* next_obj = cur + oop_size; |
| while (next_obj < top) { |
| // Keep filtering the remembered set. |
| if (!g1h->is_obj_dead(cur_oop, hr)) { |
| // Bottom lies entirely below top, so we can call the |
| // non-memRegion version of oop_iterate below. |
| cur_oop->oop_iterate(cl); |
| } |
| cur = next_obj; |
| cur_oop = oop(cur); |
| oop_size = cur_oop->size(); |
| next_obj = cur + oop_size; |
| } |
| return cur; |
| } |
| |
| void HeapRegionDCTOC::walk_mem_region_with_cl(MemRegion mr, |
| HeapWord* bottom, |
| HeapWord* top, |
| OopClosure* cl) { |
| G1CollectedHeap* g1h = _g1; |
| |
| int oop_size; |
| |
| OopClosure* cl2 = cl; |
| FilterIntoCSClosure intoCSFilt(this, g1h, cl); |
| FilterOutOfRegionClosure outOfRegionFilt(_hr, cl); |
| switch (_fk) { |
| case IntoCSFilterKind: cl2 = &intoCSFilt; break; |
| case OutOfRegionFilterKind: cl2 = &outOfRegionFilt; break; |
| } |
| |
| // Start filtering what we add to the remembered set. If the object is |
| // not considered dead, either because it is marked (in the mark bitmap) |
| // or it was allocated after marking finished, then we add it. Otherwise |
| // we can safely ignore the object. |
| if (!g1h->is_obj_dead(oop(bottom), _hr)) { |
| oop_size = oop(bottom)->oop_iterate(cl2, mr); |
| } else { |
| oop_size = oop(bottom)->size(); |
| } |
| |
| bottom += oop_size; |
| |
| if (bottom < top) { |
| // We replicate the loop below for several kinds of possible filters. |
| switch (_fk) { |
| case NoFilterKind: |
| bottom = walk_mem_region_loop(cl, g1h, _hr, bottom, top); |
| break; |
| case IntoCSFilterKind: { |
| FilterIntoCSClosure filt(this, g1h, cl); |
| bottom = walk_mem_region_loop(&filt, g1h, _hr, bottom, top); |
| break; |
| } |
| case OutOfRegionFilterKind: { |
| FilterOutOfRegionClosure filt(_hr, cl); |
| bottom = walk_mem_region_loop(&filt, g1h, _hr, bottom, top); |
| break; |
| } |
| default: |
| ShouldNotReachHere(); |
| } |
| |
| // Last object. Need to do dead-obj filtering here too. |
| if (!g1h->is_obj_dead(oop(bottom), _hr)) { |
| oop(bottom)->oop_iterate(cl2, mr); |
| } |
| } |
| } |
| |
| // Minimum region size; we won't go lower than that. |
| // We might want to decrease this in the future, to deal with small |
| // heaps a bit more efficiently. |
| #define MIN_REGION_SIZE ( 1024 * 1024 ) |
| |
| // Maximum region size; we don't go higher than that. There's a good |
| // reason for having an upper bound. We don't want regions to get too |
| // large, otherwise cleanup's effectiveness would decrease as there |
| // will be fewer opportunities to find totally empty regions after |
| // marking. |
| #define MAX_REGION_SIZE ( 32 * 1024 * 1024 ) |
| |
| // The automatic region size calculation will try to have around this |
| // many regions in the heap (based on the min heap size). |
| #define TARGET_REGION_NUMBER 2048 |
| |
| void HeapRegion::setup_heap_region_size(uintx min_heap_size) { |
| // region_size in bytes |
| uintx region_size = G1HeapRegionSize; |
| if (FLAG_IS_DEFAULT(G1HeapRegionSize)) { |
| // We base the automatic calculation on the min heap size. This |
| // can be problematic if the spread between min and max is quite |
| // wide, imagine -Xms128m -Xmx32g. But, if we decided it based on |
| // the max size, the region size might be way too large for the |
| // min size. Either way, some users might have to set the region |
| // size manually for some -Xms / -Xmx combos. |
| |
| region_size = MAX2(min_heap_size / TARGET_REGION_NUMBER, |
| (uintx) MIN_REGION_SIZE); |
| } |
| |
| int region_size_log = log2_long((jlong) region_size); |
| // Recalculate the region size to make sure it's a power of |
| // 2. This means that region_size is the largest power of 2 that's |
| // <= what we've calculated so far. |
| region_size = ((uintx)1 << region_size_log); |
| |
| // Now make sure that we don't go over or under our limits. |
| if (region_size < MIN_REGION_SIZE) { |
| region_size = MIN_REGION_SIZE; |
| } else if (region_size > MAX_REGION_SIZE) { |
| region_size = MAX_REGION_SIZE; |
| } |
| |
| // And recalculate the log. |
| region_size_log = log2_long((jlong) region_size); |
| |
| // Now, set up the globals. |
| guarantee(LogOfHRGrainBytes == 0, "we should only set it once"); |
| LogOfHRGrainBytes = region_size_log; |
| |
| guarantee(LogOfHRGrainWords == 0, "we should only set it once"); |
| LogOfHRGrainWords = LogOfHRGrainBytes - LogHeapWordSize; |
| |
| guarantee(GrainBytes == 0, "we should only set it once"); |
| // The cast to int is safe, given that we've bounded region_size by |
| // MIN_REGION_SIZE and MAX_REGION_SIZE. |
| GrainBytes = (int) region_size; |
| |
| guarantee(GrainWords == 0, "we should only set it once"); |
| GrainWords = GrainBytes >> LogHeapWordSize; |
| guarantee(1 << LogOfHRGrainWords == GrainWords, "sanity"); |
| |
| guarantee(CardsPerRegion == 0, "we should only set it once"); |
| CardsPerRegion = GrainBytes >> CardTableModRefBS::card_shift; |
| } |
| |
| void HeapRegion::reset_after_compaction() { |
| G1OffsetTableContigSpace::reset_after_compaction(); |
| // After a compaction the mark bitmap is invalid, so we must |
| // treat all objects as being inside the unmarked area. |
| zero_marked_bytes(); |
| init_top_at_mark_start(); |
| } |
| |
| DirtyCardToOopClosure* |
| HeapRegion::new_dcto_closure(OopClosure* cl, |
| CardTableModRefBS::PrecisionStyle precision, |
| HeapRegionDCTOC::FilterKind fk) { |
| return new HeapRegionDCTOC(G1CollectedHeap::heap(), |
| this, cl, precision, fk); |
| } |
| |
| void HeapRegion::hr_clear(bool par, bool clear_space) { |
| assert(_humongous_type == NotHumongous, |
| "we should have already filtered out humongous regions"); |
| assert(_humongous_start_region == NULL, |
| "we should have already filtered out humongous regions"); |
| assert(_end == _orig_end, |
| "we should have already filtered out humongous regions"); |
| |
| _in_collection_set = false; |
| _is_gc_alloc_region = false; |
| |
| set_young_index_in_cset(-1); |
| uninstall_surv_rate_group(); |
| set_young_type(NotYoung); |
| |
| if (!par) { |
| // If this is parallel, this will be done later. |
| HeapRegionRemSet* hrrs = rem_set(); |
| if (hrrs != NULL) hrrs->clear(); |
| _claimed = InitialClaimValue; |
| } |
| zero_marked_bytes(); |
| set_sort_index(-1); |
| |
| _offsets.resize(HeapRegion::GrainWords); |
| init_top_at_mark_start(); |
| if (clear_space) clear(SpaceDecorator::Mangle); |
| } |
| |
| // <PREDICTION> |
| void HeapRegion::calc_gc_efficiency() { |
| G1CollectedHeap* g1h = G1CollectedHeap::heap(); |
| _gc_efficiency = (double) garbage_bytes() / |
| g1h->predict_region_elapsed_time_ms(this, false); |
| } |
| // </PREDICTION> |
| |
| void HeapRegion::set_startsHumongous(HeapWord* new_top, HeapWord* new_end) { |
| assert(!isHumongous(), "sanity / pre-condition"); |
| assert(end() == _orig_end, |
| "Should be normal before the humongous object allocation"); |
| assert(top() == bottom(), "should be empty"); |
| assert(bottom() <= new_top && new_top <= new_end, "pre-condition"); |
| |
| _humongous_type = StartsHumongous; |
| _humongous_start_region = this; |
| |
| set_end(new_end); |
| _offsets.set_for_starts_humongous(new_top); |
| } |
| |
| void HeapRegion::set_continuesHumongous(HeapRegion* first_hr) { |
| assert(!isHumongous(), "sanity / pre-condition"); |
| assert(end() == _orig_end, |
| "Should be normal before the humongous object allocation"); |
| assert(top() == bottom(), "should be empty"); |
| assert(first_hr->startsHumongous(), "pre-condition"); |
| |
| _humongous_type = ContinuesHumongous; |
| _humongous_start_region = first_hr; |
| } |
| |
| void HeapRegion::set_notHumongous() { |
| assert(isHumongous(), "pre-condition"); |
| |
| if (startsHumongous()) { |
| assert(top() <= end(), "pre-condition"); |
| set_end(_orig_end); |
| if (top() > end()) { |
| // at least one "continues humongous" region after it |
| set_top(end()); |
| } |
| } else { |
| // continues humongous |
| assert(end() == _orig_end, "sanity"); |
| } |
| |
| assert(capacity() == (size_t) HeapRegion::GrainBytes, "pre-condition"); |
| _humongous_type = NotHumongous; |
| _humongous_start_region = NULL; |
| } |
| |
| bool HeapRegion::claimHeapRegion(jint claimValue) { |
| jint current = _claimed; |
| if (current != claimValue) { |
| jint res = Atomic::cmpxchg(claimValue, &_claimed, current); |
| if (res == current) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| HeapWord* HeapRegion::next_block_start_careful(HeapWord* addr) { |
| HeapWord* low = addr; |
| HeapWord* high = end(); |
| while (low < high) { |
| size_t diff = pointer_delta(high, low); |
| // Must add one below to bias toward the high amount. Otherwise, if |
| // "high" were at the desired value, and "low" were one less, we |
| // would not converge on "high". This is not symmetric, because |
| // we set "high" to a block start, which might be the right one, |
| // which we don't do for "low". |
| HeapWord* middle = low + (diff+1)/2; |
| if (middle == high) return high; |
| HeapWord* mid_bs = block_start_careful(middle); |
| if (mid_bs < addr) { |
| low = middle; |
| } else { |
| high = mid_bs; |
| } |
| } |
| assert(low == high && low >= addr, "Didn't work."); |
| return low; |
| } |
| |
| void HeapRegion::initialize(MemRegion mr, bool clear_space, bool mangle_space) { |
| G1OffsetTableContigSpace::initialize(mr, false, mangle_space); |
| hr_clear(false/*par*/, clear_space); |
| } |
| #ifdef _MSC_VER // the use of 'this' below gets a warning, make it go away |
| #pragma warning( disable:4355 ) // 'this' : used in base member initializer list |
| #endif // _MSC_VER |
| |
| |
| HeapRegion:: |
| HeapRegion(G1BlockOffsetSharedArray* sharedOffsetArray, |
| MemRegion mr, bool is_zeroed) |
| : G1OffsetTableContigSpace(sharedOffsetArray, mr, is_zeroed), |
| _next_fk(HeapRegionDCTOC::NoFilterKind), |
| _hrs_index(-1), |
| _humongous_type(NotHumongous), _humongous_start_region(NULL), |
| _in_collection_set(false), _is_gc_alloc_region(false), |
| _next_in_special_set(NULL), _orig_end(NULL), |
| _claimed(InitialClaimValue), _evacuation_failed(false), |
| _prev_marked_bytes(0), _next_marked_bytes(0), _sort_index(-1), |
| _young_type(NotYoung), _next_young_region(NULL), |
| _next_dirty_cards_region(NULL), _next(NULL), _pending_removal(false), |
| #ifdef ASSERT |
| _containing_set(NULL), |
| #endif // ASSERT |
| _young_index_in_cset(-1), _surv_rate_group(NULL), _age_index(-1), |
| _rem_set(NULL), _recorded_rs_length(0), _predicted_elapsed_time_ms(0), |
| _predicted_bytes_to_copy(0) |
| { |
| _orig_end = mr.end(); |
| // Note that initialize() will set the start of the unmarked area of the |
| // region. |
| this->initialize(mr, !is_zeroed, SpaceDecorator::Mangle); |
| set_top(bottom()); |
| set_saved_mark(); |
| |
| _rem_set = new HeapRegionRemSet(sharedOffsetArray, this); |
| |
| assert(HeapRegionRemSet::num_par_rem_sets() > 0, "Invariant."); |
| // In case the region is allocated during a pause, note the top. |
| // We haven't done any counting on a brand new region. |
| _top_at_conc_mark_count = bottom(); |
| } |
| |
| class NextCompactionHeapRegionClosure: public HeapRegionClosure { |
| const HeapRegion* _target; |
| bool _target_seen; |
| HeapRegion* _last; |
| CompactibleSpace* _res; |
| public: |
| NextCompactionHeapRegionClosure(const HeapRegion* target) : |
| _target(target), _target_seen(false), _res(NULL) {} |
| bool doHeapRegion(HeapRegion* cur) { |
| if (_target_seen) { |
| if (!cur->isHumongous()) { |
| _res = cur; |
| return true; |
| } |
| } else if (cur == _target) { |
| _target_seen = true; |
| } |
| return false; |
| } |
| CompactibleSpace* result() { return _res; } |
| }; |
| |
| CompactibleSpace* HeapRegion::next_compaction_space() const { |
| G1CollectedHeap* g1h = G1CollectedHeap::heap(); |
| // cast away const-ness |
| HeapRegion* r = (HeapRegion*) this; |
| NextCompactionHeapRegionClosure blk(r); |
| g1h->heap_region_iterate_from(r, &blk); |
| return blk.result(); |
| } |
| |
| void HeapRegion::save_marks() { |
| set_saved_mark(); |
| } |
| |
| void HeapRegion::oops_in_mr_iterate(MemRegion mr, OopClosure* cl) { |
| HeapWord* p = mr.start(); |
| HeapWord* e = mr.end(); |
| oop obj; |
| while (p < e) { |
| obj = oop(p); |
| p += obj->oop_iterate(cl); |
| } |
| assert(p == e, "bad memregion: doesn't end on obj boundary"); |
| } |
| |
| #define HeapRegion_OOP_SINCE_SAVE_MARKS_DEFN(OopClosureType, nv_suffix) \ |
| void HeapRegion::oop_since_save_marks_iterate##nv_suffix(OopClosureType* cl) { \ |
| ContiguousSpace::oop_since_save_marks_iterate##nv_suffix(cl); \ |
| } |
| SPECIALIZED_SINCE_SAVE_MARKS_CLOSURES(HeapRegion_OOP_SINCE_SAVE_MARKS_DEFN) |
| |
| |
| void HeapRegion::oop_before_save_marks_iterate(OopClosure* cl) { |
| oops_in_mr_iterate(MemRegion(bottom(), saved_mark_word()), cl); |
| } |
| |
| HeapWord* |
| HeapRegion::object_iterate_mem_careful(MemRegion mr, |
| ObjectClosure* cl) { |
| G1CollectedHeap* g1h = G1CollectedHeap::heap(); |
| // We used to use "block_start_careful" here. But we're actually happy |
| // to update the BOT while we do this... |
| HeapWord* cur = block_start(mr.start()); |
| mr = mr.intersection(used_region()); |
| if (mr.is_empty()) return NULL; |
| // Otherwise, find the obj that extends onto mr.start(). |
| |
| assert(cur <= mr.start() |
| && (oop(cur)->klass_or_null() == NULL || |
| cur + oop(cur)->size() > mr.start()), |
| "postcondition of block_start"); |
| oop obj; |
| while (cur < mr.end()) { |
| obj = oop(cur); |
| if (obj->klass_or_null() == NULL) { |
| // Ran into an unparseable point. |
| return cur; |
| } else if (!g1h->is_obj_dead(obj)) { |
| cl->do_object(obj); |
| } |
| if (cl->abort()) return cur; |
| // The check above must occur before the operation below, since an |
| // abort might invalidate the "size" operation. |
| cur += obj->size(); |
| } |
| return NULL; |
| } |
| |
| HeapWord* |
| HeapRegion:: |
| oops_on_card_seq_iterate_careful(MemRegion mr, |
| FilterOutOfRegionClosure* cl, |
| bool filter_young) { |
| G1CollectedHeap* g1h = G1CollectedHeap::heap(); |
| |
| // If we're within a stop-world GC, then we might look at a card in a |
| // GC alloc region that extends onto a GC LAB, which may not be |
| // parseable. Stop such at the "saved_mark" of the region. |
| if (G1CollectedHeap::heap()->is_gc_active()) { |
| mr = mr.intersection(used_region_at_save_marks()); |
| } else { |
| mr = mr.intersection(used_region()); |
| } |
| if (mr.is_empty()) return NULL; |
| // Otherwise, find the obj that extends onto mr.start(). |
| |
| // The intersection of the incoming mr (for the card) and the |
| // allocated part of the region is non-empty. This implies that |
| // we have actually allocated into this region. The code in |
| // G1CollectedHeap.cpp that allocates a new region sets the |
| // is_young tag on the region before allocating. Thus we |
| // safely know if this region is young. |
| if (is_young() && filter_young) { |
| return NULL; |
| } |
| |
| assert(!is_young(), "check value of filter_young"); |
| |
| // We used to use "block_start_careful" here. But we're actually happy |
| // to update the BOT while we do this... |
| HeapWord* cur = block_start(mr.start()); |
| assert(cur <= mr.start(), "Postcondition"); |
| |
| while (cur <= mr.start()) { |
| if (oop(cur)->klass_or_null() == NULL) { |
| // Ran into an unparseable point. |
| return cur; |
| } |
| // Otherwise... |
| int sz = oop(cur)->size(); |
| if (cur + sz > mr.start()) break; |
| // Otherwise, go on. |
| cur = cur + sz; |
| } |
| oop obj; |
| obj = oop(cur); |
| // If we finish this loop... |
| assert(cur <= mr.start() |
| && obj->klass_or_null() != NULL |
| && cur + obj->size() > mr.start(), |
| "Loop postcondition"); |
| if (!g1h->is_obj_dead(obj)) { |
| obj->oop_iterate(cl, mr); |
| } |
| |
| HeapWord* next; |
| while (cur < mr.end()) { |
| obj = oop(cur); |
| if (obj->klass_or_null() == NULL) { |
| // Ran into an unparseable point. |
| return cur; |
| }; |
| // Otherwise: |
| next = (cur + obj->size()); |
| if (!g1h->is_obj_dead(obj)) { |
| if (next < mr.end()) { |
| obj->oop_iterate(cl); |
| } else { |
| // this obj spans the boundary. If it's an array, stop at the |
| // boundary. |
| if (obj->is_objArray()) { |
| obj->oop_iterate(cl, mr); |
| } else { |
| obj->oop_iterate(cl); |
| } |
| } |
| } |
| cur = next; |
| } |
| return NULL; |
| } |
| |
| void HeapRegion::print() const { print_on(gclog_or_tty); } |
| void HeapRegion::print_on(outputStream* st) const { |
| if (isHumongous()) { |
| if (startsHumongous()) |
| st->print(" HS"); |
| else |
| st->print(" HC"); |
| } else { |
| st->print(" "); |
| } |
| if (in_collection_set()) |
| st->print(" CS"); |
| else if (is_gc_alloc_region()) |
| st->print(" A "); |
| else |
| st->print(" "); |
| if (is_young()) |
| st->print(is_survivor() ? " SU" : " Y "); |
| else |
| st->print(" "); |
| if (is_empty()) |
| st->print(" F"); |
| else |
| st->print(" "); |
| st->print(" %5d", _gc_time_stamp); |
| st->print(" PTAMS "PTR_FORMAT" NTAMS "PTR_FORMAT, |
| prev_top_at_mark_start(), next_top_at_mark_start()); |
| G1OffsetTableContigSpace::print_on(st); |
| } |
| |
| void HeapRegion::verify(bool allow_dirty) const { |
| bool dummy = false; |
| verify(allow_dirty, /* use_prev_marking */ true, /* failures */ &dummy); |
| } |
| |
| // This really ought to be commoned up into OffsetTableContigSpace somehow. |
| // We would need a mechanism to make that code skip dead objects. |
| |
| void HeapRegion::verify(bool allow_dirty, |
| bool use_prev_marking, |
| bool* failures) const { |
| G1CollectedHeap* g1 = G1CollectedHeap::heap(); |
| *failures = false; |
| HeapWord* p = bottom(); |
| HeapWord* prev_p = NULL; |
| VerifyLiveClosure vl_cl(g1, use_prev_marking); |
| bool is_humongous = isHumongous(); |
| bool do_bot_verify = !is_young(); |
| size_t object_num = 0; |
| while (p < top()) { |
| oop obj = oop(p); |
| size_t obj_size = obj->size(); |
| object_num += 1; |
| |
| if (is_humongous != g1->isHumongous(obj_size)) { |
| gclog_or_tty->print_cr("obj "PTR_FORMAT" is of %shumongous size (" |
| SIZE_FORMAT" words) in a %shumongous region", |
| p, g1->isHumongous(obj_size) ? "" : "non-", |
| obj_size, is_humongous ? "" : "non-"); |
| *failures = true; |
| return; |
| } |
| |
| // If it returns false, verify_for_object() will output the |
| // appropriate messasge. |
| if (do_bot_verify && !_offsets.verify_for_object(p, obj_size)) { |
| *failures = true; |
| return; |
| } |
| |
| if (!g1->is_obj_dead_cond(obj, this, use_prev_marking)) { |
| if (obj->is_oop()) { |
| klassOop klass = obj->klass(); |
| if (!klass->is_perm()) { |
| gclog_or_tty->print_cr("klass "PTR_FORMAT" of object "PTR_FORMAT" " |
| "not in perm", klass, obj); |
| *failures = true; |
| return; |
| } else if (!klass->is_klass()) { |
| gclog_or_tty->print_cr("klass "PTR_FORMAT" of object "PTR_FORMAT" " |
| "not a klass", klass, obj); |
| *failures = true; |
| return; |
| } else { |
| vl_cl.set_containing_obj(obj); |
| obj->oop_iterate(&vl_cl); |
| if (vl_cl.failures()) { |
| *failures = true; |
| } |
| if (G1MaxVerifyFailures >= 0 && |
| vl_cl.n_failures() >= G1MaxVerifyFailures) { |
| return; |
| } |
| } |
| } else { |
| gclog_or_tty->print_cr(PTR_FORMAT" no an oop", obj); |
| *failures = true; |
| return; |
| } |
| } |
| prev_p = p; |
| p += obj_size; |
| } |
| |
| if (p != top()) { |
| gclog_or_tty->print_cr("end of last object "PTR_FORMAT" " |
| "does not match top "PTR_FORMAT, p, top()); |
| *failures = true; |
| return; |
| } |
| |
| HeapWord* the_end = end(); |
| assert(p == top(), "it should still hold"); |
| // Do some extra BOT consistency checking for addresses in the |
| // range [top, end). BOT look-ups in this range should yield |
| // top. No point in doing that if top == end (there's nothing there). |
| if (p < the_end) { |
| // Look up top |
| HeapWord* addr_1 = p; |
| HeapWord* b_start_1 = _offsets.block_start_const(addr_1); |
| if (b_start_1 != p) { |
| gclog_or_tty->print_cr("BOT look up for top: "PTR_FORMAT" " |
| " yielded "PTR_FORMAT", expecting "PTR_FORMAT, |
| addr_1, b_start_1, p); |
| *failures = true; |
| return; |
| } |
| |
| // Look up top + 1 |
| HeapWord* addr_2 = p + 1; |
| if (addr_2 < the_end) { |
| HeapWord* b_start_2 = _offsets.block_start_const(addr_2); |
| if (b_start_2 != p) { |
| gclog_or_tty->print_cr("BOT look up for top + 1: "PTR_FORMAT" " |
| " yielded "PTR_FORMAT", expecting "PTR_FORMAT, |
| addr_2, b_start_2, p); |
| *failures = true; |
| return; |
| } |
| } |
| |
| // Look up an address between top and end |
| size_t diff = pointer_delta(the_end, p) / 2; |
| HeapWord* addr_3 = p + diff; |
| if (addr_3 < the_end) { |
| HeapWord* b_start_3 = _offsets.block_start_const(addr_3); |
| if (b_start_3 != p) { |
| gclog_or_tty->print_cr("BOT look up for top + diff: "PTR_FORMAT" " |
| " yielded "PTR_FORMAT", expecting "PTR_FORMAT, |
| addr_3, b_start_3, p); |
| *failures = true; |
| return; |
| } |
| } |
| |
| // Loook up end - 1 |
| HeapWord* addr_4 = the_end - 1; |
| HeapWord* b_start_4 = _offsets.block_start_const(addr_4); |
| if (b_start_4 != p) { |
| gclog_or_tty->print_cr("BOT look up for end - 1: "PTR_FORMAT" " |
| " yielded "PTR_FORMAT", expecting "PTR_FORMAT, |
| addr_4, b_start_4, p); |
| *failures = true; |
| return; |
| } |
| } |
| |
| if (is_humongous && object_num > 1) { |
| gclog_or_tty->print_cr("region ["PTR_FORMAT","PTR_FORMAT"] is humongous " |
| "but has "SIZE_FORMAT", objects", |
| bottom(), end(), object_num); |
| *failures = true; |
| return; |
| } |
| } |
| |
| // G1OffsetTableContigSpace code; copied from space.cpp. Hope this can go |
| // away eventually. |
| |
| void G1OffsetTableContigSpace::initialize(MemRegion mr, bool clear_space, bool mangle_space) { |
| // false ==> we'll do the clearing if there's clearing to be done. |
| ContiguousSpace::initialize(mr, false, mangle_space); |
| _offsets.zero_bottom_entry(); |
| _offsets.initialize_threshold(); |
| if (clear_space) clear(mangle_space); |
| } |
| |
| void G1OffsetTableContigSpace::clear(bool mangle_space) { |
| ContiguousSpace::clear(mangle_space); |
| _offsets.zero_bottom_entry(); |
| _offsets.initialize_threshold(); |
| } |
| |
| void G1OffsetTableContigSpace::set_bottom(HeapWord* new_bottom) { |
| Space::set_bottom(new_bottom); |
| _offsets.set_bottom(new_bottom); |
| } |
| |
| void G1OffsetTableContigSpace::set_end(HeapWord* new_end) { |
| Space::set_end(new_end); |
| _offsets.resize(new_end - bottom()); |
| } |
| |
| void G1OffsetTableContigSpace::print() const { |
| print_short(); |
| gclog_or_tty->print_cr(" [" INTPTR_FORMAT ", " INTPTR_FORMAT ", " |
| INTPTR_FORMAT ", " INTPTR_FORMAT ")", |
| bottom(), top(), _offsets.threshold(), end()); |
| } |
| |
| HeapWord* G1OffsetTableContigSpace::initialize_threshold() { |
| return _offsets.initialize_threshold(); |
| } |
| |
| HeapWord* G1OffsetTableContigSpace::cross_threshold(HeapWord* start, |
| HeapWord* end) { |
| _offsets.alloc_block(start, end); |
| return _offsets.threshold(); |
| } |
| |
| HeapWord* G1OffsetTableContigSpace::saved_mark_word() const { |
| G1CollectedHeap* g1h = G1CollectedHeap::heap(); |
| assert( _gc_time_stamp <= g1h->get_gc_time_stamp(), "invariant" ); |
| if (_gc_time_stamp < g1h->get_gc_time_stamp()) |
| return top(); |
| else |
| return ContiguousSpace::saved_mark_word(); |
| } |
| |
| void G1OffsetTableContigSpace::set_saved_mark() { |
| G1CollectedHeap* g1h = G1CollectedHeap::heap(); |
| unsigned curr_gc_time_stamp = g1h->get_gc_time_stamp(); |
| |
| if (_gc_time_stamp < curr_gc_time_stamp) { |
| // The order of these is important, as another thread might be |
| // about to start scanning this region. If it does so after |
| // set_saved_mark and before _gc_time_stamp = ..., then the latter |
| // will be false, and it will pick up top() as the high water mark |
| // of region. If it does so after _gc_time_stamp = ..., then it |
| // will pick up the right saved_mark_word() as the high water mark |
| // of the region. Either way, the behaviour will be correct. |
| ContiguousSpace::set_saved_mark(); |
| OrderAccess::storestore(); |
| _gc_time_stamp = curr_gc_time_stamp; |
| // The following fence is to force a flush of the writes above, but |
| // is strictly not needed because when an allocating worker thread |
| // calls set_saved_mark() it does so under the ParGCRareEvent_lock; |
| // when the lock is released, the write will be flushed. |
| // OrderAccess::fence(); |
| } |
| } |
| |
| G1OffsetTableContigSpace:: |
| G1OffsetTableContigSpace(G1BlockOffsetSharedArray* sharedOffsetArray, |
| MemRegion mr, bool is_zeroed) : |
| _offsets(sharedOffsetArray, mr), |
| _par_alloc_lock(Mutex::leaf, "OffsetTableContigSpace par alloc lock", true), |
| _gc_time_stamp(0) |
| { |
| _offsets.set_space(this); |
| initialize(mr, !is_zeroed, SpaceDecorator::Mangle); |
| } |
