src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp

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rev 6757 : 8051973: Eager reclaim leaves marks of marked but reclaimed objects on the next bitmap
Summary: Eager reclaim also needs to clear marks of eagerly reclaimed regions if they have already been marked during concurrent mark.
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*** 6534,6543 **** --- 6534,6546 ---- return false; } G1CollectedHeap* g1h = G1CollectedHeap::heap(); + oop obj = (oop)r->bottom(); + CMBitMap* next_bitmap = g1h->concurrent_mark()->nextMarkBitMap(); + // The following checks whether the humongous object is live are sufficient. // The main additional check (in addition to having a reference from the roots // or the young gen) is whether the humongous object has a remembered set entry. // // A humongous object cannot be live if there is no remembered set for it
*** 6570,6610 **** uint region_idx = r->hrs_index(); if (g1h->humongous_is_live(region_idx) || g1h->humongous_region_is_always_live(region_idx)) { if (G1TraceReclaimDeadHumongousObjectsAtYoungGC) { ! gclog_or_tty->print_cr("Live humongous %d region %d with remset "SIZE_FORMAT" code roots "SIZE_FORMAT" is dead-bitmap %d live-other %d obj array %d", r->isHumongous(), region_idx, r->rem_set()->occupied(), r->rem_set()->strong_code_roots_list_length(), ! g1h->mark_in_progress() && !g1h->g1_policy()->during_initial_mark_pause(), g1h->humongous_is_live(region_idx), ! oop(r->bottom())->is_objArray() ); } return false; } ! guarantee(!((oop)(r->bottom()))->is_objArray(), err_msg("Eagerly reclaiming object arrays is not supported, but the object "PTR_FORMAT" is.", r->bottom())); if (G1TraceReclaimDeadHumongousObjectsAtYoungGC) { ! gclog_or_tty->print_cr("Reclaim humongous region %d start "PTR_FORMAT" region %d length "UINT32_FORMAT" with remset "SIZE_FORMAT" code roots "SIZE_FORMAT" is dead-bitmap %d live-other %d obj array %d", r->isHumongous(), r->bottom(), region_idx, r->region_num(), r->rem_set()->occupied(), r->rem_set()->strong_code_roots_list_length(), ! g1h->mark_in_progress() && !g1h->g1_policy()->during_initial_mark_pause(), g1h->humongous_is_live(region_idx), ! oop(r->bottom())->is_objArray() ); } _freed_bytes += r->used(); r->set_containing_set(NULL); _humongous_regions_removed.increment(1u, r->capacity()); g1h->free_humongous_region(r, _free_region_list, false); --- 6573,6617 ---- uint region_idx = r->hrs_index(); if (g1h->humongous_is_live(region_idx) || g1h->humongous_region_is_always_live(region_idx)) { if (G1TraceReclaimDeadHumongousObjectsAtYoungGC) { ! gclog_or_tty->print_cr("Live humongous %d region %d with remset "SIZE_FORMAT" code roots "SIZE_FORMAT" is marked %d live-other %d obj array %d", r->isHumongous(), region_idx, r->rem_set()->occupied(), r->rem_set()->strong_code_roots_list_length(), ! next_bitmap->isMarked(r->bottom()), g1h->humongous_is_live(region_idx), ! obj->is_objArray() ); } return false; } ! guarantee(!obj->is_objArray(), err_msg("Eagerly reclaiming object arrays is not supported, but the object "PTR_FORMAT" is.", r->bottom())); if (G1TraceReclaimDeadHumongousObjectsAtYoungGC) { ! gclog_or_tty->print_cr("Reclaim humongous region %d start "PTR_FORMAT" region %d length "UINT32_FORMAT" with remset "SIZE_FORMAT" code roots "SIZE_FORMAT" is marked %d live-other %d obj array %d", r->isHumongous(), r->bottom(), region_idx, r->region_num(), r->rem_set()->occupied(), r->rem_set()->strong_code_roots_list_length(), ! next_bitmap->isMarked(r->bottom()), g1h->humongous_is_live(region_idx), ! obj->is_objArray() ); } + // Need to clear mark bit of the humongous object if already set. + if (next_bitmap->isMarked(r->bottom())) { + next_bitmap->clear(r->bottom()); + } _freed_bytes += r->used(); r->set_containing_set(NULL); _humongous_regions_removed.increment(1u, r->capacity()); g1h->free_humongous_region(r, _free_region_list, false);