1 /* 2 * Copyright (c) 2017, 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.hpp" 27 #include "gc/g1/g1ConcurrentMarkBitMap.inline.hpp" 28 #include "gc/g1/g1FullCollector.hpp" 29 #include "gc/g1/g1FullGCCompactionPoint.hpp" 30 #include "gc/g1/g1FullGCCompactTask.hpp" 31 #include "gc/g1/heapRegion.inline.hpp" 32 #include "gc/shared/gcTraceTime.inline.hpp" 33 #include "logging/log.hpp" 34 #include "utilities/ticks.inline.hpp" 35 36 class G1ResetHumongousClosure : public HeapRegionClosure { 37 G1CMBitMap* _bitmap; 38 39 public: 40 G1ResetHumongousClosure(G1CMBitMap* bitmap) : 41 _bitmap(bitmap) { } 42 43 bool doHeapRegion(HeapRegion* current) { 44 if (current->is_humongous()) { 45 if (current->is_starts_humongous()) { 46 oop obj = oop(current->bottom()); 47 if (_bitmap->is_marked(obj)) { 48 // Clear bitmap and fix mark word. 49 _bitmap->clear(obj); 50 obj->init_mark(); 51 } else { 52 assert(current->is_empty(), "Should have been cleared in phase 2."); 53 } 54 } 55 current->reset_during_compaction(); 56 } 57 return false; 58 } 59 }; 60 61 size_t G1FullGCCompactTask::G1CompactRegionClosure::apply(oop obj) { 62 size_t size = obj->size(); 63 HeapWord* destination = (HeapWord*)obj->forwardee(); 64 if (destination == NULL) { 65 // Object not moving 66 return size; 67 } 68 69 // copy object and reinit its mark 70 HeapWord* obj_addr = (HeapWord*) obj; 71 assert(obj_addr != destination, "everything in this pass should be moving"); 72 Copy::aligned_conjoint_words(obj_addr, destination, size); 73 oop(destination)->init_mark(); 74 assert(oop(destination)->klass() != NULL, "should have a class"); 75 76 return size; 77 } 78 79 void G1FullGCCompactTask::compact_region(HeapRegion* hr) { 80 assert(!hr->is_humongous(), "Should be no humongous regions in compaction queue"); 81 G1CompactRegionClosure compact(collector()->mark_bitmap()); 82 hr->apply_to_marked_objects(collector()->mark_bitmap(), &compact); 83 // Once all objects have been moved the liveness information 84 // needs be cleared. 85 collector()->mark_bitmap()->clear_region(hr); 86 hr->complete_compaction(); 87 } 88 89 void G1FullGCCompactTask::work(uint worker_id) { 90 Ticks start = Ticks::now(); 91 GrowableArray<HeapRegion*>* compaction_queue = collector()->compaction_point(worker_id)->regions(); 92 for (GrowableArrayIterator<HeapRegion*> it = compaction_queue->begin(); 93 it != compaction_queue->end(); 94 ++it) { 95 compact_region(*it); 96 } 97 98 G1ResetHumongousClosure hc(collector()->mark_bitmap()); 99 G1CollectedHeap::heap()->heap_region_par_iterate_from_worker_offset(&hc, &_claimer, worker_id); 100 log_task("Compaction task", worker_id, start); 101 } 102 103 void G1FullGCCompactTask::serial_compaction() { 104 GCTraceTime(Debug, gc, phases) tm("Phase 4: Serial Compaction", collector()->scope()->timer()); 105 GrowableArray<HeapRegion*>* compaction_queue = collector()->serial_compaction_point()->regions(); 106 for (GrowableArrayIterator<HeapRegion*> it = compaction_queue->begin(); 107 it != compaction_queue->end(); 108 ++it) { 109 compact_region(*it); 110 } 111 }