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/g1CollectionSetCandidates.hpp"
  27 #include "gc/g1/g1CollectionSetChooser.hpp"
  28 #include "gc/g1/heapRegion.inline.hpp"
  29 
  30 void G1CollectionSetCandidates::remove(uint num_regions) {
  31   assert(num_regions <= num_remaining(), "Trying to remove more regions (%u) than available (%u)", num_regions, num_remaining());
  32   for (uint i = 0; i < num_regions; i++) {
  33     _remaining_reclaimable_bytes -= at(_front_idx)->reclaimable_bytes();
  34     _front_idx++;
  35   }
  36 }
  37 
  38 void G1CollectionSetCandidates::iterate(HeapRegionClosure* cl) {
  39   for (uint i = _front_idx; i < _num_regions; i++) {
  40     HeapRegion* r = _regions[i];
  41     if (cl->do_heap_region(r)) {
  42       cl->set_incomplete();
  43       break;
  44     }
  45   }
  46 }
  47 
  48 #ifndef PRODUCT
  49 void G1CollectionSetCandidates::verify() const {
  50   guarantee(_front_idx <= _num_regions, "Index: %u Num_regions: %u", _front_idx, _num_regions);
  51   uint idx = _front_idx;
  52   size_t sum_of_reclaimable_bytes = 0;
  53   HeapRegion *prev = NULL;
  54   for (; idx < _num_regions; idx++) {
  55     HeapRegion *cur = _regions[idx];
  56     guarantee(cur != NULL, "Regions after _front_idx %u cannot be NULL but %u is", _front_idx, idx);
  57     guarantee(G1CollectionSetChooser::should_add(cur), "Region %u should be eligible for addition.", cur->hrm_index());
  58     if (prev != NULL) {
  59       guarantee(prev->gc_efficiency() >= cur->gc_efficiency(),
  60                 "GC efficiency for region %u: %1.4f smaller than for region %u: %1.4f",
  61                 prev->hrm_index(), prev->gc_efficiency(), cur->hrm_index(), cur->gc_efficiency());
  62     }
  63     sum_of_reclaimable_bytes += cur->reclaimable_bytes();
  64     prev = cur;
  65   }
  66   guarantee(sum_of_reclaimable_bytes == _remaining_reclaimable_bytes,
  67             "Inconsistent remaining_reclaimable bytes, remaining " SIZE_FORMAT " calculated " SIZE_FORMAT,
  68             _remaining_reclaimable_bytes, sum_of_reclaimable_bytes);
  69 }
  70 #endif // !PRODUCT