1 /* 2 * Copyright (c) 2017, 2022, 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 */ 24 25 #include "precompiled.hpp" 26 #include "gc/g1/g1CollectedHeap.inline.hpp" 27 #include "gc/g1/g1ConcurrentMarkBitMap.inline.hpp" 28 #include "gc/g1/g1FullCollector.inline.hpp" 29 #include "gc/g1/g1FullGCCompactionPoint.hpp" 30 #include "gc/g1/g1FullGCMarker.hpp" 31 #include "gc/g1/g1FullGCOopClosures.inline.hpp" 32 #include "gc/g1/g1FullGCPrepareTask.inline.hpp" 33 #include "gc/g1/g1HotCardCache.hpp" 34 #include "gc/g1/heapRegion.inline.hpp" 35 #include "gc/shared/gcTraceTime.inline.hpp" 36 #include "gc/shared/referenceProcessor.hpp" 37 #include "logging/log.hpp" 38 #include "memory/iterator.inline.hpp" 39 #include "oops/oop.inline.hpp" 40 #include "utilities/ticks.hpp" 41 42 G1DetermineCompactionQueueClosure::G1DetermineCompactionQueueClosure(G1FullCollector* collector) : 43 _g1h(G1CollectedHeap::heap()), 44 _collector(collector), 45 _cur_worker(0) { } 46 47 bool G1FullGCPrepareTask::G1CalculatePointersClosure::do_heap_region(HeapRegion* hr) { 48 uint region_idx = hr->hrm_index(); 49 assert(_collector->is_compaction_target(region_idx), "must be"); 50 51 assert(!hr->is_pinned(), "must be"); 52 assert(!hr->is_closed_archive(), "must be"); 53 assert(!hr->is_open_archive(), "must be"); 54 55 prepare_for_compaction(hr); 56 57 return false; 58 } 59 60 G1FullGCPrepareTask::G1FullGCPrepareTask(G1FullCollector* collector) : 61 G1FullGCTask("G1 Prepare Compact Task", collector), 62 _has_free_compaction_targets(false), 63 _hrclaimer(collector->workers()) { 64 } 65 66 void G1FullGCPrepareTask::set_has_free_compaction_targets() { 67 if (!_has_free_compaction_targets) { 68 _has_free_compaction_targets = true; 69 } 70 } 71 72 bool G1FullGCPrepareTask::has_free_compaction_targets() { 73 return _has_free_compaction_targets; 74 } 75 76 void G1FullGCPrepareTask::work(uint worker_id) { 77 Ticks start = Ticks::now(); 78 // Calculate the target locations for the objects in the non-free regions of 79 // the compaction queues provided by the associate compaction point. 80 { 81 G1FullGCCompactionPoint* compaction_point = collector()->compaction_point(worker_id); 82 G1CalculatePointersClosure closure(collector(), compaction_point); 83 84 for (GrowableArrayIterator<HeapRegion*> it = compaction_point->regions()->begin(); 85 it != compaction_point->regions()->end(); 86 ++it) { 87 closure.do_heap_region(*it); 88 } 89 compaction_point->update(); 90 // Determine if there are any unused compaction targets. This is only the case if 91 // there are 92 // - any regions in queue, so no free ones either. 93 // - and the current region is not the last one in the list. 94 if (compaction_point->has_regions() && 95 compaction_point->current_region() != compaction_point->regions()->last()) { 96 set_has_free_compaction_targets(); 97 } 98 } 99 100 // Clear region metadata that is invalid after GC for all regions. 101 { 102 G1ResetMetadataClosure closure(collector()); 103 G1CollectedHeap::heap()->heap_region_par_iterate_from_start(&closure, &_hrclaimer); 104 } 105 log_task("Prepare compaction task", worker_id, start); 106 } 107 108 G1FullGCPrepareTask::G1CalculatePointersClosure::G1CalculatePointersClosure(G1FullCollector* collector, 109 G1FullGCCompactionPoint* cp) : 110 _g1h(G1CollectedHeap::heap()), 111 _collector(collector), 112 _bitmap(collector->mark_bitmap()), 113 _cp(cp) { } 114 115 G1FullGCPrepareTask::G1ResetMetadataClosure::G1ResetMetadataClosure(G1FullCollector* collector) : 116 _g1h(G1CollectedHeap::heap()), 117 _collector(collector) { } 118 119 void G1FullGCPrepareTask::G1ResetMetadataClosure::reset_region_metadata(HeapRegion* hr) { 120 hr->rem_set()->clear(); 121 hr->clear_cardtable(); 122 123 G1HotCardCache* hcc = _g1h->hot_card_cache(); 124 if (hcc->use_cache()) { 125 hcc->reset_card_counts(hr); 126 } 127 } 128 129 bool G1FullGCPrepareTask::G1ResetMetadataClosure::do_heap_region(HeapRegion* hr) { 130 uint const region_idx = hr->hrm_index(); 131 if (!_collector->is_compaction_target(region_idx)) { 132 assert(!hr->is_free(), "all free regions should be compaction targets"); 133 assert(_collector->is_skip_compacting(region_idx) || hr->is_closed_archive(), "must be"); 134 if (hr->is_young()) { 135 // G1 updates the BOT for old region contents incrementally, but young regions 136 // lack BOT information for performance reasons. 137 // Recreate BOT information of high live ratio young regions here to keep expected 138 // performance during scanning their card tables in the collection pauses later. 139 hr->update_bot(); 140 } 141 } 142 143 // Reset data structures not valid after Full GC. 144 reset_region_metadata(hr); 145 146 return false; 147 } 148 149 G1FullGCPrepareTask::G1PrepareCompactLiveClosure::G1PrepareCompactLiveClosure(G1FullGCCompactionPoint* cp) : 150 _cp(cp) { } 151 152 size_t G1FullGCPrepareTask::G1PrepareCompactLiveClosure::apply(oop object) { 153 size_t size = object->size(); 154 _cp->forward(object, size); 155 return size; 156 } 157 158 void G1FullGCPrepareTask::G1CalculatePointersClosure::prepare_for_compaction(HeapRegion* hr) { 159 if (!_collector->is_free(hr->hrm_index())) { 160 G1PrepareCompactLiveClosure prepare_compact(_cp); 161 hr->apply_to_marked_objects(_bitmap, &prepare_compact); 162 } 163 }