src/mem/ruby/filters/MultiGrainBloomFilter.cc

   1 /*
   2  * Copyright (c) 1999-2008 Mark D. Hill and David A. Wood
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include "base/intmath.hh"
  30 #include "base/str.hh"
  31 #include "mem/ruby/filters/MultiGrainBloomFilter.hh"
  32 #include "mem/ruby/system/System.hh"
  33
  34 using namespace std;
  35
  36 MultiGrainBloomFilter::MultiGrainBloomFilter(string str)
  37 {
  38     string head, tail;
  39 #ifndef NDEBUG
  40     bool success =
  41 #endif
  42         split_first(str, head, tail, '_');
  43     assert(success);
  44
  45     // head contains size of 1st bloom filter, tail contains size of
  46     // 2nd bloom filter
  47
  48     m_filter_size = atoi(head.c_str());
  49     m_filter_size_bits = floorLog2(m_filter_size);
  50
  51     m_page_filter_size = atoi(tail.c_str());
  52     m_page_filter_size_bits = floorLog2(m_page_filter_size);
  53
  54     m_filter.resize(m_filter_size);
  55     m_page_filter.resize(m_page_filter_size);
  56     clear();
  57 }
  58
  59 MultiGrainBloomFilter::~MultiGrainBloomFilter()
  60 {
  61 }
  62
  63 void
  64 MultiGrainBloomFilter::clear()
  65 {
  66     for (int i = 0; i < m_filter_size; i++) {
  67         m_filter[i] = 0;
  68     }
  69     for(int i=0; i < m_page_filter_size; ++i){
  70         m_page_filter[i] = 0;
  71     }
  72 }
  73
  74 void
  75 MultiGrainBloomFilter::increment(Addr addr)
  76 {
  77     // Not used
  78 }
  79
  80
  81 void
  82 MultiGrainBloomFilter::decrement(Addr addr)
  83 {
  84     // Not used
  85 }
  86
  87 void
  88 MultiGrainBloomFilter::merge(AbstractBloomFilter *other_filter)
  89 {
  90     // TODO
  91 }
  92
  93 void
  94 MultiGrainBloomFilter::set(Addr addr)
  95 {
  96     int i = get_block_index(addr);
  97     assert(i < m_filter_size);
  98     assert(get_page_index(addr) < m_page_filter_size);
  99     m_filter[i] = 1;
 100     m_page_filter[i] = 1;
 101
 102 }
 103
 104 void
 105 MultiGrainBloomFilter::unset(Addr addr)
 106 {
 107     // not used
 108 }
 109
 110 bool
 111 MultiGrainBloomFilter::isSet(Addr addr)
 112 {
 113     int i = get_block_index(addr);
 114     assert(i < m_filter_size);
 115     assert(get_page_index(addr) < m_page_filter_size);
 116     // we have to have both indices set
 117     return (m_filter[i] && m_page_filter[i]);
 118 }
 119
 120 int
 121 MultiGrainBloomFilter::getCount(Addr addr)
 122 {
 123     // not used
 124     return 0;
 125 }
 126
 127 int
 128 MultiGrainBloomFilter::getTotalCount()
 129 {
 130     int count = 0;
 131
 132     for (int i = 0; i < m_filter_size; i++) {
 133         count += m_filter[i];
 134     }
 135
 136     for(int i=0; i < m_page_filter_size; ++i) {
 137         count += m_page_filter[i] = 0;
 138     }
 139
 140     return count;
 141 }
 142
 143 int
 144 MultiGrainBloomFilter::getIndex(Addr addr)
 145 {
 146     return 0;
 147     // TODO
 148 }
 149
 150 int
 151 MultiGrainBloomFilter::readBit(const int index)
 152 {
 153     return 0;
 154     // TODO
 155 }
 156
 157 void
 158 MultiGrainBloomFilter::writeBit(const int index, const int value)
 159 {
 160     // TODO
 161 }
 162
 163 void
 164 MultiGrainBloomFilter::print(ostream& out) const
 165 {
 166 }
 167
 168 int
 169 MultiGrainBloomFilter::get_block_index(Addr addr)
 170 {
 171     // grap a chunk of bits after byte offset
 172     return bitSelect(addr, RubySystem::getBlockSizeBits(),
 173                      RubySystem::getBlockSizeBits() +
 174                      m_filter_size_bits - 1);
 175 }
 176
 177 int
 178 MultiGrainBloomFilter::get_page_index(Addr addr)
 179 {
 180     int bits = RubySystem::getBlockSizeBits() + m_filter_size_bits - 1;
 181
 182     // grap a chunk of bits after first chunk
 183     return bitSelect(addr, bits, bits + m_page_filter_size_bits - 1);
 184 }
 185
 186
 187
 188