ysr@777: /*
ysr@777:  * Copyright 2001-2007 Sun Microsystems, Inc.  All Rights Reserved.
ysr@777:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
ysr@777:  *
ysr@777:  * This code is free software; you can redistribute it and/or modify it
ysr@777:  * under the terms of the GNU General Public License version 2 only, as
ysr@777:  * published by the Free Software Foundation.
ysr@777:  *
ysr@777:  * This code is distributed in the hope that it will be useful, but WITHOUT
ysr@777:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
ysr@777:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
ysr@777:  * version 2 for more details (a copy is included in the LICENSE file that
ysr@777:  * accompanied this code).
ysr@777:  *
ysr@777:  * You should have received a copy of the GNU General Public License version
ysr@777:  * 2 along with this work; if not, write to the Free Software Foundation,
ysr@777:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
ysr@777:  *
ysr@777:  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
ysr@777:  * CA 95054 USA or visit www.sun.com if you need additional information or
ysr@777:  * have any questions.
ysr@777:  *
ysr@777:  */
ysr@777: 
ysr@777: #include "incls/_precompiled.incl"
ysr@777: #include "incls/_heapRegion.cpp.incl"
ysr@777: 
ysr@777: HeapRegionDCTOC::HeapRegionDCTOC(G1CollectedHeap* g1,
ysr@777:                                  HeapRegion* hr, OopClosure* cl,
ysr@777:                                  CardTableModRefBS::PrecisionStyle precision,
ysr@777:                                  FilterKind fk) :
ysr@777:   ContiguousSpaceDCTOC(hr, cl, precision, NULL),
ysr@777:   _hr(hr), _fk(fk), _g1(g1)
ysr@777: {}
ysr@777: 
ysr@777: FilterOutOfRegionClosure::FilterOutOfRegionClosure(HeapRegion* r,
ysr@777:                                                    OopClosure* oc) :
ysr@777:   _r_bottom(r->bottom()), _r_end(r->end()),
ysr@777:   _oc(oc), _out_of_region(0)
ysr@777: {}
ysr@777: 
ysr@777: class VerifyLiveClosure: public OopClosure {
ysr@777:   G1CollectedHeap* _g1h;
ysr@777:   CardTableModRefBS* _bs;
ysr@777:   oop _containing_obj;
ysr@777:   bool _failures;
ysr@777:   int _n_failures;
ysr@777: public:
ysr@777:   VerifyLiveClosure(G1CollectedHeap* g1h) :
ysr@777:     _g1h(g1h), _bs(NULL), _containing_obj(NULL),
ysr@777:     _failures(false), _n_failures(0)
ysr@777:   {
ysr@777:     BarrierSet* bs = _g1h->barrier_set();
ysr@777:     if (bs->is_a(BarrierSet::CardTableModRef))
ysr@777:       _bs = (CardTableModRefBS*)bs;
ysr@777:   }
ysr@777: 
ysr@777:   void set_containing_obj(oop obj) {
ysr@777:     _containing_obj = obj;
ysr@777:   }
ysr@777: 
ysr@777:   bool failures() { return _failures; }
ysr@777:   int n_failures() { return _n_failures; }
ysr@777: 
ysr@777:   virtual void do_oop(narrowOop* p) {
ysr@777:     guarantee(false, "NYI");
ysr@777:   }
ysr@777: 
ysr@777:   void do_oop(oop* p) {
ysr@777:     assert(_containing_obj != NULL, "Precondition");
ysr@777:     assert(!_g1h->is_obj_dead(_containing_obj), "Precondition");
ysr@777:     oop obj = *p;
ysr@777:     if (obj != NULL) {
ysr@777:       bool failed = false;
ysr@777:       if (!_g1h->is_in_closed_subset(obj) || _g1h->is_obj_dead(obj)) {
ysr@777:         if (!_failures) {
ysr@777:           gclog_or_tty->print_cr("");
ysr@777:           gclog_or_tty->print_cr("----------");
ysr@777:         }
ysr@777:         if (!_g1h->is_in_closed_subset(obj)) {
ysr@777:           gclog_or_tty->print_cr("Field "PTR_FORMAT
ysr@777:                         " of live obj "PTR_FORMAT
ysr@777:                         " points to obj "PTR_FORMAT
ysr@777:                         " not in the heap.",
ysr@777:                         p, (void*) _containing_obj, (void*) obj);
ysr@777:         } else {
ysr@777:           gclog_or_tty->print_cr("Field "PTR_FORMAT
ysr@777:                         " of live obj "PTR_FORMAT
ysr@777:                         " points to dead obj "PTR_FORMAT".",
ysr@777:                         p, (void*) _containing_obj, (void*) obj);
ysr@777:         }
ysr@777:         gclog_or_tty->print_cr("Live obj:");
ysr@777:         _containing_obj->print_on(gclog_or_tty);
ysr@777:         gclog_or_tty->print_cr("Bad referent:");
ysr@777:         obj->print_on(gclog_or_tty);
ysr@777:         gclog_or_tty->print_cr("----------");
ysr@777:         _failures = true;
ysr@777:         failed = true;
ysr@777:         _n_failures++;
ysr@777:       }
ysr@777: 
ysr@777:       if (!_g1h->full_collection()) {
ysr@777:         HeapRegion* from = _g1h->heap_region_containing(p);
ysr@777:         HeapRegion* to   = _g1h->heap_region_containing(*p);
ysr@777:         if (from != NULL && to != NULL &&
ysr@777:             from != to &&
ysr@777:             !to->popular() &&
ysr@777:             !to->isHumongous()) {
ysr@777:           jbyte cv_obj = *_bs->byte_for_const(_containing_obj);
ysr@777:           jbyte cv_field = *_bs->byte_for_const(p);
ysr@777:           const jbyte dirty = CardTableModRefBS::dirty_card_val();
ysr@777: 
ysr@777:           bool is_bad = !(from->is_young()
ysr@777:                           || to->rem_set()->contains_reference(p)
ysr@777:                           || !G1HRRSFlushLogBuffersOnVerify && // buffers were not flushed
ysr@777:                               (_containing_obj->is_objArray() ?
ysr@777:                                   cv_field == dirty
ysr@777:                                : cv_obj == dirty || cv_field == dirty));
ysr@777:           if (is_bad) {
ysr@777:             if (!_failures) {
ysr@777:               gclog_or_tty->print_cr("");
ysr@777:               gclog_or_tty->print_cr("----------");
ysr@777:             }
ysr@777:             gclog_or_tty->print_cr("Missing rem set entry:");
ysr@777:             gclog_or_tty->print_cr("Field "PTR_FORMAT
ysr@777:                           " of obj "PTR_FORMAT
ysr@777:                           ", in region %d ["PTR_FORMAT
ysr@777:                           ", "PTR_FORMAT"),",
ysr@777:                           p, (void*) _containing_obj,
ysr@777:                           from->hrs_index(),
ysr@777:                           from->bottom(),
ysr@777:                           from->end());
ysr@777:             _containing_obj->print_on(gclog_or_tty);
ysr@777:             gclog_or_tty->print_cr("points to obj "PTR_FORMAT
ysr@777:                           " in region %d ["PTR_FORMAT
ysr@777:                           ", "PTR_FORMAT").",
ysr@777:                           (void*) obj, to->hrs_index(),
ysr@777:                           to->bottom(), to->end());
ysr@777:             obj->print_on(gclog_or_tty);
ysr@777:             gclog_or_tty->print_cr("Obj head CTE = %d, field CTE = %d.",
ysr@777:                           cv_obj, cv_field);
ysr@777:             gclog_or_tty->print_cr("----------");
ysr@777:             _failures = true;
ysr@777:             if (!failed) _n_failures++;
ysr@777:           }
ysr@777:         }
ysr@777:       }
ysr@777:     }
ysr@777:   }
ysr@777: };
ysr@777: 
ysr@777: template<class ClosureType>
ysr@777: HeapWord* walk_mem_region_loop(ClosureType* cl, G1CollectedHeap* g1h,
ysr@777:                                HeapRegion* hr,
ysr@777:                                HeapWord* cur, HeapWord* top) {
ysr@777:   oop cur_oop = oop(cur);
ysr@777:   int oop_size = cur_oop->size();
ysr@777:   HeapWord* next_obj = cur + oop_size;
ysr@777:   while (next_obj < top) {
ysr@777:     // Keep filtering the remembered set.
ysr@777:     if (!g1h->is_obj_dead(cur_oop, hr)) {
ysr@777:       // Bottom lies entirely below top, so we can call the
ysr@777:       // non-memRegion version of oop_iterate below.
ysr@777: #ifndef PRODUCT
ysr@777:       if (G1VerifyMarkingInEvac) {
ysr@777:         VerifyLiveClosure vl_cl(g1h);
ysr@777:         cur_oop->oop_iterate(&vl_cl);
ysr@777:       }
ysr@777: #endif
ysr@777:       cur_oop->oop_iterate(cl);
ysr@777:     }
ysr@777:     cur = next_obj;
ysr@777:     cur_oop = oop(cur);
ysr@777:     oop_size = cur_oop->size();
ysr@777:     next_obj = cur + oop_size;
ysr@777:   }
ysr@777:   return cur;
ysr@777: }
ysr@777: 
ysr@777: void HeapRegionDCTOC::walk_mem_region_with_cl(MemRegion mr,
ysr@777:                                               HeapWord* bottom,
ysr@777:                                               HeapWord* top,
ysr@777:                                               OopClosure* cl) {
ysr@777:   G1CollectedHeap* g1h = _g1;
ysr@777: 
ysr@777:   int oop_size;
ysr@777: 
ysr@777:   OopClosure* cl2 = cl;
ysr@777:   FilterIntoCSClosure intoCSFilt(this, g1h, cl);
ysr@777:   FilterOutOfRegionClosure outOfRegionFilt(_hr, cl);
ysr@777:   switch (_fk) {
ysr@777:   case IntoCSFilterKind:      cl2 = &intoCSFilt; break;
ysr@777:   case OutOfRegionFilterKind: cl2 = &outOfRegionFilt; break;
ysr@777:   }
ysr@777: 
ysr@777:   // Start filtering what we add to the remembered set. If the object is
ysr@777:   // not considered dead, either because it is marked (in the mark bitmap)
ysr@777:   // or it was allocated after marking finished, then we add it. Otherwise
ysr@777:   // we can safely ignore the object.
ysr@777:   if (!g1h->is_obj_dead(oop(bottom), _hr)) {
ysr@777: #ifndef PRODUCT
ysr@777:     if (G1VerifyMarkingInEvac) {
ysr@777:       VerifyLiveClosure vl_cl(g1h);
ysr@777:       oop(bottom)->oop_iterate(&vl_cl, mr);
ysr@777:     }
ysr@777: #endif
ysr@777:     oop_size = oop(bottom)->oop_iterate(cl2, mr);
ysr@777:   } else {
ysr@777:     oop_size = oop(bottom)->size();
ysr@777:   }
ysr@777: 
ysr@777:   bottom += oop_size;
ysr@777: 
ysr@777:   if (bottom < top) {
ysr@777:     // We replicate the loop below for several kinds of possible filters.
ysr@777:     switch (_fk) {
ysr@777:     case NoFilterKind:
ysr@777:       bottom = walk_mem_region_loop(cl, g1h, _hr, bottom, top);
ysr@777:       break;
ysr@777:     case IntoCSFilterKind: {
ysr@777:       FilterIntoCSClosure filt(this, g1h, cl);
ysr@777:       bottom = walk_mem_region_loop(&filt, g1h, _hr, bottom, top);
ysr@777:       break;
ysr@777:     }
ysr@777:     case OutOfRegionFilterKind: {
ysr@777:       FilterOutOfRegionClosure filt(_hr, cl);
ysr@777:       bottom = walk_mem_region_loop(&filt, g1h, _hr, bottom, top);
ysr@777:       break;
ysr@777:     }
ysr@777:     default:
ysr@777:       ShouldNotReachHere();
ysr@777:     }
ysr@777: 
ysr@777:     // Last object. Need to do dead-obj filtering here too.
ysr@777:     if (!g1h->is_obj_dead(oop(bottom), _hr)) {
ysr@777: #ifndef PRODUCT
ysr@777:       if (G1VerifyMarkingInEvac) {
ysr@777:         VerifyLiveClosure vl_cl(g1h);
ysr@777:         oop(bottom)->oop_iterate(&vl_cl, mr);
ysr@777:       }
ysr@777: #endif
ysr@777:       oop(bottom)->oop_iterate(cl2, mr);
ysr@777:     }
ysr@777:   }
ysr@777: }
ysr@777: 
ysr@777: void HeapRegion::reset_after_compaction() {
ysr@777:   G1OffsetTableContigSpace::reset_after_compaction();
ysr@777:   // After a compaction the mark bitmap is invalid, so we must
ysr@777:   // treat all objects as being inside the unmarked area.
ysr@777:   zero_marked_bytes();
ysr@777:   init_top_at_mark_start();
ysr@777: }
ysr@777: 
ysr@777: 
ysr@777: 
ysr@777: DirtyCardToOopClosure*
ysr@777: HeapRegion::new_dcto_closure(OopClosure* cl,
ysr@777:                              CardTableModRefBS::PrecisionStyle precision,
ysr@777:                              HeapRegionDCTOC::FilterKind fk) {
ysr@777:   return new HeapRegionDCTOC(G1CollectedHeap::heap(),
ysr@777:                              this, cl, precision, fk);
ysr@777: }
ysr@777: 
ysr@777: void HeapRegion::hr_clear(bool par, bool clear_space) {
tonyp@790:   _humongous_type = NotHumongous;
ysr@777:   _humongous_start_region = NULL;
ysr@777:   _in_collection_set = false;
ysr@777:   _is_gc_alloc_region = false;
ysr@777: 
ysr@777:   // Age stuff (if parallel, this will be done separately, since it needs
ysr@777:   // to be sequential).
ysr@777:   G1CollectedHeap* g1h = G1CollectedHeap::heap();
ysr@777: 
ysr@777:   set_young_index_in_cset(-1);
ysr@777:   uninstall_surv_rate_group();
ysr@777:   set_young_type(NotYoung);
ysr@777: 
ysr@777:   // In case it had been the start of a humongous sequence, reset its end.
ysr@777:   set_end(_orig_end);
ysr@777: 
ysr@777:   if (!par) {
ysr@777:     // If this is parallel, this will be done later.
ysr@777:     HeapRegionRemSet* hrrs = rem_set();
ysr@777:     if (hrrs != NULL) hrrs->clear();
tonyp@790:     _claimed = InitialClaimValue;
ysr@777:   }
ysr@777:   zero_marked_bytes();
ysr@777:   set_sort_index(-1);
ysr@777:   if ((uintptr_t)bottom() >= (uintptr_t)g1h->popular_object_boundary())
ysr@777:     set_popular(false);
ysr@777: 
ysr@777:   _offsets.resize(HeapRegion::GrainWords);
ysr@777:   init_top_at_mark_start();
ysr@777:   if (clear_space) clear();
ysr@777: }
ysr@777: 
ysr@777: // <PREDICTION>
ysr@777: void HeapRegion::calc_gc_efficiency() {
ysr@777:   G1CollectedHeap* g1h = G1CollectedHeap::heap();
ysr@777:   _gc_efficiency = (double) garbage_bytes() /
ysr@777:                             g1h->predict_region_elapsed_time_ms(this, false);
ysr@777: }
ysr@777: // </PREDICTION>
ysr@777: 
ysr@777: void HeapRegion::set_startsHumongous() {
tonyp@790:   _humongous_type = StartsHumongous;
ysr@777:   _humongous_start_region = this;
ysr@777:   assert(end() == _orig_end, "Should be normal before alloc.");
ysr@777: }
ysr@777: 
ysr@777: bool HeapRegion::claimHeapRegion(jint claimValue) {
ysr@777:   jint current = _claimed;
ysr@777:   if (current != claimValue) {
ysr@777:     jint res = Atomic::cmpxchg(claimValue, &_claimed, current);
ysr@777:     if (res == current) {
ysr@777:       return true;
ysr@777:     }
ysr@777:   }
ysr@777:   return false;
ysr@777: }
ysr@777: 
ysr@777: HeapWord* HeapRegion::next_block_start_careful(HeapWord* addr) {
ysr@777:   HeapWord* low = addr;
ysr@777:   HeapWord* high = end();
ysr@777:   while (low < high) {
ysr@777:     size_t diff = pointer_delta(high, low);
ysr@777:     // Must add one below to bias toward the high amount.  Otherwise, if
ysr@777:   // "high" were at the desired value, and "low" were one less, we
ysr@777:     // would not converge on "high".  This is not symmetric, because
ysr@777:     // we set "high" to a block start, which might be the right one,
ysr@777:     // which we don't do for "low".
ysr@777:     HeapWord* middle = low + (diff+1)/2;
ysr@777:     if (middle == high) return high;
ysr@777:     HeapWord* mid_bs = block_start_careful(middle);
ysr@777:     if (mid_bs < addr) {
ysr@777:       low = middle;
ysr@777:     } else {
ysr@777:       high = mid_bs;
ysr@777:     }
ysr@777:   }
ysr@777:   assert(low == high && low >= addr, "Didn't work.");
ysr@777:   return low;
ysr@777: }
ysr@777: 
ysr@777: void HeapRegion::set_next_on_unclean_list(HeapRegion* r) {
ysr@777:   assert(r == NULL || r->is_on_unclean_list(), "Malformed unclean list.");
ysr@777:   _next_in_special_set = r;
ysr@777: }
ysr@777: 
ysr@777: void HeapRegion::set_on_unclean_list(bool b) {
ysr@777:   _is_on_unclean_list = b;
ysr@777: }
ysr@777: 
ysr@777: void HeapRegion::initialize(MemRegion mr, bool clear_space) {
ysr@777:   G1OffsetTableContigSpace::initialize(mr, false);
ysr@777:   hr_clear(false/*par*/, clear_space);
ysr@777: }
ysr@777: #ifdef _MSC_VER // the use of 'this' below gets a warning, make it go away
ysr@777: #pragma warning( disable:4355 ) // 'this' : used in base member initializer list
ysr@777: #endif // _MSC_VER
ysr@777: 
ysr@777: 
ysr@777: HeapRegion::
ysr@777: HeapRegion(G1BlockOffsetSharedArray* sharedOffsetArray,
ysr@777:                      MemRegion mr, bool is_zeroed)
ysr@777:   : G1OffsetTableContigSpace(sharedOffsetArray, mr, is_zeroed),
ysr@777:     _next_fk(HeapRegionDCTOC::NoFilterKind),
ysr@777:     _hrs_index(-1),
tonyp@790:     _humongous_type(NotHumongous), _humongous_start_region(NULL),
ysr@777:     _in_collection_set(false), _is_gc_alloc_region(false),
ysr@777:     _is_on_free_list(false), _is_on_unclean_list(false),
ysr@777:     _next_in_special_set(NULL), _orig_end(NULL),
tonyp@790:     _claimed(InitialClaimValue), _evacuation_failed(false),
ysr@777:     _prev_marked_bytes(0), _next_marked_bytes(0), _sort_index(-1),
ysr@777:     _popularity(NotPopular),
ysr@777:     _young_type(NotYoung), _next_young_region(NULL),
ysr@777:     _young_index_in_cset(-1), _surv_rate_group(NULL), _age_index(-1),
ysr@777:     _rem_set(NULL), _zfs(NotZeroFilled)
ysr@777: {
ysr@777:   _orig_end = mr.end();
ysr@777:   // Note that initialize() will set the start of the unmarked area of the
ysr@777:   // region.
ysr@777:   this->initialize(mr, !is_zeroed);
ysr@777: 
ysr@777:   _rem_set =  new HeapRegionRemSet(sharedOffsetArray, this);
ysr@777: 
ysr@777:   assert(HeapRegionRemSet::num_par_rem_sets() > 0, "Invariant.");
ysr@777:   // In case the region is allocated during a pause, note the top.
ysr@777:   // We haven't done any counting on a brand new region.
ysr@777:   _top_at_conc_mark_count = bottom();
ysr@777: }
ysr@777: 
ysr@777: class NextCompactionHeapRegionClosure: public HeapRegionClosure {
ysr@777:   const HeapRegion* _target;
ysr@777:   bool _target_seen;
ysr@777:   HeapRegion* _last;
ysr@777:   CompactibleSpace* _res;
ysr@777: public:
ysr@777:   NextCompactionHeapRegionClosure(const HeapRegion* target) :
ysr@777:     _target(target), _target_seen(false), _res(NULL) {}
ysr@777:   bool doHeapRegion(HeapRegion* cur) {
ysr@777:     if (_target_seen) {
ysr@777:       if (!cur->isHumongous()) {
ysr@777:         _res = cur;
ysr@777:         return true;
ysr@777:       }
ysr@777:     } else if (cur == _target) {
ysr@777:       _target_seen = true;
ysr@777:     }
ysr@777:     return false;
ysr@777:   }
ysr@777:   CompactibleSpace* result() { return _res; }
ysr@777: };
ysr@777: 
ysr@777: CompactibleSpace* HeapRegion::next_compaction_space() const {
ysr@777:   G1CollectedHeap* g1h = G1CollectedHeap::heap();
ysr@777:   // cast away const-ness
ysr@777:   HeapRegion* r = (HeapRegion*) this;
ysr@777:   NextCompactionHeapRegionClosure blk(r);
ysr@777:   g1h->heap_region_iterate_from(r, &blk);
ysr@777:   return blk.result();
ysr@777: }
ysr@777: 
ysr@777: void HeapRegion::set_continuesHumongous(HeapRegion* start) {
ysr@777:   // The order is important here.
ysr@777:   start->add_continuingHumongousRegion(this);
tonyp@790:   _humongous_type = ContinuesHumongous;
ysr@777:   _humongous_start_region = start;
ysr@777: }
ysr@777: 
ysr@777: void HeapRegion::add_continuingHumongousRegion(HeapRegion* cont) {
ysr@777:   // Must join the blocks of the current H region seq with the block of the
ysr@777:   // added region.
ysr@777:   offsets()->join_blocks(bottom(), cont->bottom());
ysr@777:   arrayOop obj = (arrayOop)(bottom());
ysr@777:   obj->set_length((int) (obj->length() + cont->capacity()/jintSize));
ysr@777:   set_end(cont->end());
ysr@777:   set_top(cont->end());
ysr@777: }
ysr@777: 
ysr@777: void HeapRegion::save_marks() {
ysr@777:   set_saved_mark();
ysr@777: }
ysr@777: 
ysr@777: void HeapRegion::oops_in_mr_iterate(MemRegion mr, OopClosure* cl) {
ysr@777:   HeapWord* p = mr.start();
ysr@777:   HeapWord* e = mr.end();
ysr@777:   oop obj;
ysr@777:   while (p < e) {
ysr@777:     obj = oop(p);
ysr@777:     p += obj->oop_iterate(cl);
ysr@777:   }
ysr@777:   assert(p == e, "bad memregion: doesn't end on obj boundary");
ysr@777: }
ysr@777: 
ysr@777: #define HeapRegion_OOP_SINCE_SAVE_MARKS_DEFN(OopClosureType, nv_suffix) \
ysr@777: void HeapRegion::oop_since_save_marks_iterate##nv_suffix(OopClosureType* cl) { \
ysr@777:   ContiguousSpace::oop_since_save_marks_iterate##nv_suffix(cl);              \
ysr@777: }
ysr@777: SPECIALIZED_SINCE_SAVE_MARKS_CLOSURES(HeapRegion_OOP_SINCE_SAVE_MARKS_DEFN)
ysr@777: 
ysr@777: 
ysr@777: void HeapRegion::oop_before_save_marks_iterate(OopClosure* cl) {
ysr@777:   oops_in_mr_iterate(MemRegion(bottom(), saved_mark_word()), cl);
ysr@777: }
ysr@777: 
ysr@777: #ifdef DEBUG
ysr@777: HeapWord* HeapRegion::allocate(size_t size) {
ysr@777:   jint state = zero_fill_state();
ysr@777:   assert(!G1CollectedHeap::heap()->allocs_are_zero_filled() ||
ysr@777:          zero_fill_is_allocated(),
ysr@777:          "When ZF is on, only alloc in ZF'd regions");
ysr@777:   return G1OffsetTableContigSpace::allocate(size);
ysr@777: }
ysr@777: #endif
ysr@777: 
ysr@777: void HeapRegion::set_zero_fill_state_work(ZeroFillState zfs) {
ysr@777:   assert(top() == bottom() || zfs == Allocated,
ysr@777:          "Region must be empty, or we must be setting it to allocated.");
ysr@777:   assert(ZF_mon->owned_by_self() ||
ysr@777:          Universe::heap()->is_gc_active(),
ysr@777:          "Must hold the lock or be a full GC to modify.");
ysr@777:   _zfs = zfs;
ysr@777: }
ysr@777: 
ysr@777: void HeapRegion::set_zero_fill_complete() {
ysr@777:   set_zero_fill_state_work(ZeroFilled);
ysr@777:   if (ZF_mon->owned_by_self()) {
ysr@777:     ZF_mon->notify_all();
ysr@777:   }
ysr@777: }
ysr@777: 
ysr@777: 
ysr@777: void HeapRegion::ensure_zero_filled() {
ysr@777:   MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
ysr@777:   ensure_zero_filled_locked();
ysr@777: }
ysr@777: 
ysr@777: void HeapRegion::ensure_zero_filled_locked() {
ysr@777:   assert(ZF_mon->owned_by_self(), "Precondition");
ysr@777:   bool should_ignore_zf = SafepointSynchronize::is_at_safepoint();
ysr@777:   assert(should_ignore_zf || Heap_lock->is_locked(),
ysr@777:          "Either we're in a GC or we're allocating a region.");
ysr@777:   switch (zero_fill_state()) {
ysr@777:   case HeapRegion::NotZeroFilled:
ysr@777:     set_zero_fill_in_progress(Thread::current());
ysr@777:     {
ysr@777:       ZF_mon->unlock();
ysr@777:       Copy::fill_to_words(bottom(), capacity()/HeapWordSize);
ysr@777:       ZF_mon->lock_without_safepoint_check();
ysr@777:     }
ysr@777:     // A trap.
ysr@777:     guarantee(zero_fill_state() == HeapRegion::ZeroFilling
ysr@777:               && zero_filler() == Thread::current(),
ysr@777:               "AHA!  Tell Dave D if you see this...");
ysr@777:     set_zero_fill_complete();
ysr@777:     // gclog_or_tty->print_cr("Did sync ZF.");
ysr@777:     ConcurrentZFThread::note_sync_zfs();
ysr@777:     break;
ysr@777:   case HeapRegion::ZeroFilling:
ysr@777:     if (should_ignore_zf) {
ysr@777:       // We can "break" the lock and take over the work.
ysr@777:       Copy::fill_to_words(bottom(), capacity()/HeapWordSize);
ysr@777:       set_zero_fill_complete();
ysr@777:       ConcurrentZFThread::note_sync_zfs();
ysr@777:       break;
ysr@777:     } else {
ysr@777:       ConcurrentZFThread::wait_for_ZF_completed(this);
ysr@777:     }
ysr@777:   case HeapRegion::ZeroFilled:
ysr@777:     // Nothing to do.
ysr@777:     break;
ysr@777:   case HeapRegion::Allocated:
ysr@777:     guarantee(false, "Should not call on allocated regions.");
ysr@777:   }
ysr@777:   assert(zero_fill_state() == HeapRegion::ZeroFilled, "Post");
ysr@777: }
ysr@777: 
ysr@777: HeapWord*
ysr@777: HeapRegion::object_iterate_mem_careful(MemRegion mr,
ysr@777:                                                  ObjectClosure* cl) {
ysr@777:   G1CollectedHeap* g1h = G1CollectedHeap::heap();
ysr@777:   // We used to use "block_start_careful" here.  But we're actually happy
ysr@777:   // to update the BOT while we do this...
ysr@777:   HeapWord* cur = block_start(mr.start());
ysr@777:   mr = mr.intersection(used_region());
ysr@777:   if (mr.is_empty()) return NULL;
ysr@777:   // Otherwise, find the obj that extends onto mr.start().
ysr@777: 
ysr@777:   assert(cur <= mr.start()
ysr@777:          && (oop(cur)->klass() == NULL ||
ysr@777:              cur + oop(cur)->size() > mr.start()),
ysr@777:          "postcondition of block_start");
ysr@777:   oop obj;
ysr@777:   while (cur < mr.end()) {
ysr@777:     obj = oop(cur);
ysr@777:     if (obj->klass() == NULL) {
ysr@777:       // Ran into an unparseable point.
ysr@777:       return cur;
ysr@777:     } else if (!g1h->is_obj_dead(obj)) {
ysr@777:       cl->do_object(obj);
ysr@777:     }
ysr@777:     if (cl->abort()) return cur;
ysr@777:     // The check above must occur before the operation below, since an
ysr@777:     // abort might invalidate the "size" operation.
ysr@777:     cur += obj->size();
ysr@777:   }
ysr@777:   return NULL;
ysr@777: }
ysr@777: 
ysr@777: HeapWord*
ysr@777: HeapRegion::
ysr@777: oops_on_card_seq_iterate_careful(MemRegion mr,
ysr@777:                                      FilterOutOfRegionClosure* cl) {
ysr@777:   G1CollectedHeap* g1h = G1CollectedHeap::heap();
ysr@777: 
ysr@777:   // If we're within a stop-world GC, then we might look at a card in a
ysr@777:   // GC alloc region that extends onto a GC LAB, which may not be
ysr@777:   // parseable.  Stop such at the "saved_mark" of the region.
ysr@777:   if (G1CollectedHeap::heap()->is_gc_active()) {
ysr@777:     mr = mr.intersection(used_region_at_save_marks());
ysr@777:   } else {
ysr@777:     mr = mr.intersection(used_region());
ysr@777:   }
ysr@777:   if (mr.is_empty()) return NULL;
ysr@777:   // Otherwise, find the obj that extends onto mr.start().
ysr@777: 
ysr@777:   // We used to use "block_start_careful" here.  But we're actually happy
ysr@777:   // to update the BOT while we do this...
ysr@777:   HeapWord* cur = block_start(mr.start());
ysr@777:   assert(cur <= mr.start(), "Postcondition");
ysr@777: 
ysr@777:   while (cur <= mr.start()) {
ysr@777:     if (oop(cur)->klass() == NULL) {
ysr@777:       // Ran into an unparseable point.
ysr@777:       return cur;
ysr@777:     }
ysr@777:     // Otherwise...
ysr@777:     int sz = oop(cur)->size();
ysr@777:     if (cur + sz > mr.start()) break;
ysr@777:     // Otherwise, go on.
ysr@777:     cur = cur + sz;
ysr@777:   }
ysr@777:   oop obj;
ysr@777:   obj = oop(cur);
ysr@777:   // If we finish this loop...
ysr@777:   assert(cur <= mr.start()
ysr@777:          && obj->klass() != NULL
ysr@777:          && cur + obj->size() > mr.start(),
ysr@777:          "Loop postcondition");
ysr@777:   if (!g1h->is_obj_dead(obj)) {
ysr@777:     obj->oop_iterate(cl, mr);
ysr@777:   }
ysr@777: 
ysr@777:   HeapWord* next;
ysr@777:   while (cur < mr.end()) {
ysr@777:     obj = oop(cur);
ysr@777:     if (obj->klass() == NULL) {
ysr@777:       // Ran into an unparseable point.
ysr@777:       return cur;
ysr@777:     };
ysr@777:     // Otherwise:
ysr@777:     next = (cur + obj->size());
ysr@777:     if (!g1h->is_obj_dead(obj)) {
ysr@777:       if (next < mr.end()) {
ysr@777:         obj->oop_iterate(cl);
ysr@777:       } else {
ysr@777:         // this obj spans the boundary.  If it's an array, stop at the
ysr@777:         // boundary.
ysr@777:         if (obj->is_objArray()) {
ysr@777:           obj->oop_iterate(cl, mr);
ysr@777:         } else {
ysr@777:           obj->oop_iterate(cl);
ysr@777:         }
ysr@777:       }
ysr@777:     }
ysr@777:     cur = next;
ysr@777:   }
ysr@777:   return NULL;
ysr@777: }
ysr@777: 
ysr@777: void HeapRegion::print() const { print_on(gclog_or_tty); }
ysr@777: void HeapRegion::print_on(outputStream* st) const {
ysr@777:   if (isHumongous()) {
ysr@777:     if (startsHumongous())
ysr@777:       st->print(" HS");
ysr@777:     else
ysr@777:       st->print(" HC");
ysr@777:   } else {
ysr@777:     st->print("   ");
ysr@777:   }
ysr@777:   if (in_collection_set())
ysr@777:     st->print(" CS");
ysr@777:   else if (is_gc_alloc_region())
ysr@777:     st->print(" A ");
ysr@777:   else
ysr@777:     st->print("   ");
ysr@777:   if (is_young())
ysr@777:     st->print(is_scan_only() ? " SO" : (is_survivor() ? " SU" : " Y "));
ysr@777:   else
ysr@777:     st->print("   ");
ysr@777:   if (is_empty())
ysr@777:     st->print(" F");
ysr@777:   else
ysr@777:     st->print("  ");
ysr@777:   st->print(" %d", _gc_time_stamp);
ysr@777:   G1OffsetTableContigSpace::print_on(st);
ysr@777: }
ysr@777: 
ysr@777: #define OBJ_SAMPLE_INTERVAL 0
ysr@777: #define BLOCK_SAMPLE_INTERVAL 100
ysr@777: 
ysr@777: // This really ought to be commoned up into OffsetTableContigSpace somehow.
ysr@777: // We would need a mechanism to make that code skip dead objects.
ysr@777: 
ysr@777: void HeapRegion::verify(bool allow_dirty) const {
ysr@777:   G1CollectedHeap* g1 = G1CollectedHeap::heap();
ysr@777:   HeapWord* p = bottom();
ysr@777:   HeapWord* prev_p = NULL;
ysr@777:   int objs = 0;
ysr@777:   int blocks = 0;
ysr@777:   VerifyLiveClosure vl_cl(g1);
ysr@777:   while (p < top()) {
ysr@777:     size_t size = oop(p)->size();
ysr@777:     if (blocks == BLOCK_SAMPLE_INTERVAL) {
ysr@777:       guarantee(p == block_start_const(p + (size/2)),
ysr@777:                 "check offset computation");
ysr@777:       blocks = 0;
ysr@777:     } else {
ysr@777:       blocks++;
ysr@777:     }
ysr@777:     if (objs == OBJ_SAMPLE_INTERVAL) {
ysr@777:       oop obj = oop(p);
ysr@777:       if (!g1->is_obj_dead(obj, this)) {
ysr@777:         obj->verify();
ysr@777:         vl_cl.set_containing_obj(obj);
ysr@777:         obj->oop_iterate(&vl_cl);
ysr@777:         if (G1MaxVerifyFailures >= 0
ysr@777:             && vl_cl.n_failures() >= G1MaxVerifyFailures) break;
ysr@777:       }
ysr@777:       objs = 0;
ysr@777:     } else {
ysr@777:       objs++;
ysr@777:     }
ysr@777:     prev_p = p;
ysr@777:     p += size;
ysr@777:   }
ysr@777:   HeapWord* rend = end();
ysr@777:   HeapWord* rtop = top();
ysr@777:   if (rtop < rend) {
ysr@777:     guarantee(block_start_const(rtop + (rend - rtop) / 2) == rtop,
ysr@777:               "check offset computation");
ysr@777:   }
ysr@777:   if (vl_cl.failures()) {
ysr@777:     gclog_or_tty->print_cr("Heap:");
ysr@777:     G1CollectedHeap::heap()->print();
ysr@777:     gclog_or_tty->print_cr("");
ysr@777:   }
ysr@777:   if (G1VerifyConcMark &&
ysr@777:       G1VerifyConcMarkPrintReachable &&
ysr@777:       vl_cl.failures()) {
ysr@777:     g1->concurrent_mark()->print_prev_bitmap_reachable();
ysr@777:   }
ysr@777:   guarantee(!vl_cl.failures(), "should not have had any failures");
ysr@777:   guarantee(p == top(), "end of last object must match end of space");
ysr@777: }
ysr@777: 
ysr@777: // G1OffsetTableContigSpace code; copied from space.cpp.  Hope this can go
ysr@777: // away eventually.
ysr@777: 
ysr@777: void G1OffsetTableContigSpace::initialize(MemRegion mr, bool clear_space) {
ysr@777:   // false ==> we'll do the clearing if there's clearing to be done.
ysr@777:   ContiguousSpace::initialize(mr, false);
ysr@777:   _offsets.zero_bottom_entry();
ysr@777:   _offsets.initialize_threshold();
ysr@777:   if (clear_space) clear();
ysr@777: }
ysr@777: 
ysr@777: void G1OffsetTableContigSpace::clear() {
ysr@777:   ContiguousSpace::clear();
ysr@777:   _offsets.zero_bottom_entry();
ysr@777:   _offsets.initialize_threshold();
ysr@777: }
ysr@777: 
ysr@777: void G1OffsetTableContigSpace::set_bottom(HeapWord* new_bottom) {
ysr@777:   Space::set_bottom(new_bottom);
ysr@777:   _offsets.set_bottom(new_bottom);
ysr@777: }
ysr@777: 
ysr@777: void G1OffsetTableContigSpace::set_end(HeapWord* new_end) {
ysr@777:   Space::set_end(new_end);
ysr@777:   _offsets.resize(new_end - bottom());
ysr@777: }
ysr@777: 
ysr@777: void G1OffsetTableContigSpace::print() const {
ysr@777:   print_short();
ysr@777:   gclog_or_tty->print_cr(" [" INTPTR_FORMAT ", " INTPTR_FORMAT ", "
ysr@777:                 INTPTR_FORMAT ", " INTPTR_FORMAT ")",
ysr@777:                 bottom(), top(), _offsets.threshold(), end());
ysr@777: }
ysr@777: 
ysr@777: HeapWord* G1OffsetTableContigSpace::initialize_threshold() {
ysr@777:   return _offsets.initialize_threshold();
ysr@777: }
ysr@777: 
ysr@777: HeapWord* G1OffsetTableContigSpace::cross_threshold(HeapWord* start,
ysr@777:                                                     HeapWord* end) {
ysr@777:   _offsets.alloc_block(start, end);
ysr@777:   return _offsets.threshold();
ysr@777: }
ysr@777: 
ysr@777: HeapWord* G1OffsetTableContigSpace::saved_mark_word() const {
ysr@777:   G1CollectedHeap* g1h = G1CollectedHeap::heap();
ysr@777:   assert( _gc_time_stamp <= g1h->get_gc_time_stamp(), "invariant" );
ysr@777:   if (_gc_time_stamp < g1h->get_gc_time_stamp())
ysr@777:     return top();
ysr@777:   else
ysr@777:     return ContiguousSpace::saved_mark_word();
ysr@777: }
ysr@777: 
ysr@777: void G1OffsetTableContigSpace::set_saved_mark() {
ysr@777:   G1CollectedHeap* g1h = G1CollectedHeap::heap();
ysr@777:   unsigned curr_gc_time_stamp = g1h->get_gc_time_stamp();
ysr@777: 
ysr@777:   if (_gc_time_stamp < curr_gc_time_stamp) {
ysr@777:     // The order of these is important, as another thread might be
ysr@777:     // about to start scanning this region. If it does so after
ysr@777:     // set_saved_mark and before _gc_time_stamp = ..., then the latter
ysr@777:     // will be false, and it will pick up top() as the high water mark
ysr@777:     // of region. If it does so after _gc_time_stamp = ..., then it
ysr@777:     // will pick up the right saved_mark_word() as the high water mark
ysr@777:     // of the region. Either way, the behaviour will be correct.
ysr@777:     ContiguousSpace::set_saved_mark();
iveresov@788:     _gc_time_stamp = curr_gc_time_stamp;
iveresov@788:     OrderAccess::fence();
ysr@777:   }
ysr@777: }
ysr@777: 
ysr@777: G1OffsetTableContigSpace::
ysr@777: G1OffsetTableContigSpace(G1BlockOffsetSharedArray* sharedOffsetArray,
ysr@777:                          MemRegion mr, bool is_zeroed) :
ysr@777:   _offsets(sharedOffsetArray, mr),
ysr@777:   _par_alloc_lock(Mutex::leaf, "OffsetTableContigSpace par alloc lock", true),
ysr@777:   _gc_time_stamp(0)
ysr@777: {
ysr@777:   _offsets.set_space(this);
ysr@777:   initialize(mr, !is_zeroed);
ysr@777: }
ysr@777: 
ysr@777: size_t RegionList::length() {
ysr@777:   size_t len = 0;
ysr@777:   HeapRegion* cur = hd();
ysr@777:   DEBUG_ONLY(HeapRegion* last = NULL);
ysr@777:   while (cur != NULL) {
ysr@777:     len++;
ysr@777:     DEBUG_ONLY(last = cur);
ysr@777:     cur = get_next(cur);
ysr@777:   }
ysr@777:   assert(last == tl(), "Invariant");
ysr@777:   return len;
ysr@777: }
ysr@777: 
ysr@777: void RegionList::insert_before_head(HeapRegion* r) {
ysr@777:   assert(well_formed(), "Inv");
ysr@777:   set_next(r, hd());
ysr@777:   _hd = r;
ysr@777:   _sz++;
ysr@777:   if (tl() == NULL) _tl = r;
ysr@777:   assert(well_formed(), "Inv");
ysr@777: }
ysr@777: 
ysr@777: void RegionList::prepend_list(RegionList* new_list) {
ysr@777:   assert(well_formed(), "Precondition");
ysr@777:   assert(new_list->well_formed(), "Precondition");
ysr@777:   HeapRegion* new_tl = new_list->tl();
ysr@777:   if (new_tl != NULL) {
ysr@777:     set_next(new_tl, hd());
ysr@777:     _hd = new_list->hd();
ysr@777:     _sz += new_list->sz();
ysr@777:     if (tl() == NULL) _tl = new_list->tl();
ysr@777:   } else {
ysr@777:     assert(new_list->hd() == NULL && new_list->sz() == 0, "Inv");
ysr@777:   }
ysr@777:   assert(well_formed(), "Inv");
ysr@777: }
ysr@777: 
ysr@777: void RegionList::delete_after(HeapRegion* r) {
ysr@777:   assert(well_formed(), "Precondition");
ysr@777:   HeapRegion* next = get_next(r);
ysr@777:   assert(r != NULL, "Precondition");
ysr@777:   HeapRegion* next_tl = get_next(next);
ysr@777:   set_next(r, next_tl);
ysr@777:   dec_sz();
ysr@777:   if (next == tl()) {
ysr@777:     assert(next_tl == NULL, "Inv");
ysr@777:     _tl = r;
ysr@777:   }
ysr@777:   assert(well_formed(), "Inv");
ysr@777: }
ysr@777: 
ysr@777: HeapRegion* RegionList::pop() {
ysr@777:   assert(well_formed(), "Inv");
ysr@777:   HeapRegion* res = hd();
ysr@777:   if (res != NULL) {
ysr@777:     _hd = get_next(res);
ysr@777:     _sz--;
ysr@777:     set_next(res, NULL);
ysr@777:     if (sz() == 0) _tl = NULL;
ysr@777:   }
ysr@777:   assert(well_formed(), "Inv");
ysr@777:   return res;
ysr@777: }