1 /* 2 * Copyright (c) 2019, 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/collectionSetChooser.hpp" 27 #include "gc/g1/g1CollectionSetCandidates.hpp" 28 #include "gc/g1/heapRegion.inline.hpp" 29 30 HeapRegion* G1CollectionSetCandidates::pop_front() { 31 assert(_front_idx < _num_regions, "pre-condition"); 32 HeapRegion* hr = _regions[_front_idx]; 33 assert(hr != NULL, "pre-condition"); 34 _regions[_front_idx] = NULL; 35 assert(hr->reclaimable_bytes() <= _remaining_reclaimable_bytes, 36 "Remaining reclaimable bytes inconsistent " 37 "from region: " SIZE_FORMAT " remaining: " SIZE_FORMAT, 38 hr->reclaimable_bytes(), _remaining_reclaimable_bytes); 39 _remaining_reclaimable_bytes -= hr->reclaimable_bytes(); 40 _front_idx++; 41 return hr; 42 } 43 44 void G1CollectionSetCandidates::push_front(HeapRegion* hr) { 45 assert(hr != NULL, "Can't put back a NULL region"); 46 assert(_front_idx >= 1, "Too many regions have been put back."); 47 _front_idx--; 48 _regions[_front_idx] = hr; 49 _remaining_reclaimable_bytes += hr->reclaimable_bytes(); 50 } 51 52 void G1CollectionSetCandidates::iterate(HeapRegionClosure* cl) { 53 for (uint i = _front_idx; i < _num_regions; i++) { 54 HeapRegion* r = _regions[i]; 55 if (cl->do_heap_region(r)) { 56 cl->set_incomplete(); 57 break; 58 } 59 } 60 } 61 62 #ifndef PRODUCT 63 void G1CollectionSetCandidates::verify() const { 64 guarantee(_front_idx <= _num_regions, "Index: %u Num_regions: %u", _front_idx, _num_regions); 65 uint idx = 0; 66 size_t sum_of_reclaimable_bytes = 0; 67 while (idx < _front_idx) { 68 guarantee(_regions[idx] == NULL, "All entries before _front_idx %u should be NULL, but %u is not", 69 _front_idx, idx); 70 idx++; 71 } 72 HeapRegion *prev = NULL; 73 for (; idx < _num_regions; idx++) { 74 HeapRegion *cur = _regions[idx]; 75 guarantee(cur != NULL, "Regions after _front_idx %u cannot be NULL but %u is", _front_idx, idx); 76 guarantee(CollectionSetChooser::should_add(cur), "Region %u should be eligible for addition.", cur->hrm_index()); 77 if (prev != NULL) { 78 guarantee(prev->gc_efficiency() >= cur->gc_efficiency(), 79 "GC efficiency for region %u: %1.4f smaller than for region %u: %1.4f", 80 prev->hrm_index(), prev->gc_efficiency(), cur->hrm_index(), cur->gc_efficiency()); 81 } 82 sum_of_reclaimable_bytes += cur->reclaimable_bytes(); 83 prev = cur; 84 } 85 guarantee(sum_of_reclaimable_bytes == _remaining_reclaimable_bytes, 86 "Inconsistent remaining_reclaimable bytes, remaining " SIZE_FORMAT " calculated " SIZE_FORMAT, 87 _remaining_reclaimable_bytes, sum_of_reclaimable_bytes); 88 } 89 #endif // !PRODUCT