1 /*
   2  * Copyright (c) 2014, 2018, 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 #include "precompiled.hpp"
  25 #include "jfr/leakprofiler/chains/bitset.hpp"
  26 #include "jfr/recorder/storage/jfrVirtualMemory.hpp"
  27 #include "memory/memRegion.hpp"
  28 
  29 BitSet::BitSet(const MemRegion& covered_region) :
  30   _vmm(NULL),
  31   _region_start(covered_region.start()),
  32   _region_size(covered_region.word_size()) {
  33 }
  34 
  35 BitSet::~BitSet() {
  36   delete _vmm;
  37 }
  38 
  39 bool BitSet::initialize() {
  40   assert(_vmm == NULL, "invariant");
  41   _vmm = new JfrVirtualMemory();
  42   if (_vmm == NULL) {
  43     return false;
  44   }
  45 
  46   const BitMap::idx_t bits = _region_size >> LogMinObjAlignment;
  47   const size_t words = bits / BitsPerWord;
  48   const size_t raw_bytes = words * sizeof(BitMap::idx_t);
  49 
  50   // the virtual memory invocation will reserve and commit the entire space
  51   BitMap::bm_word_t* map = (BitMap::bm_word_t*)_vmm->initialize(raw_bytes, raw_bytes);
  52   if (map == NULL) {
  53     return false;
  54   }
  55   _bits = BitMap(map, bits);
  56   return true;
  57 }
  58