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/gems_common/Map.hh"
  32 #include "mem/ruby/common/Address.hh"
  33 #include "mem/ruby/filters/MultiGrainBloomFilter.hh"
  34
  35 using namespace std;
  36
  37 MultiGrainBloomFilter::MultiGrainBloomFilter(string str)
  38 {
  39     string head, tail;
  40 #ifndef NDEBUG
  41     bool success =
  42 #endif
  43         split_first(str, head, tail, '_');
  44     assert(success);
  45
  46     // head contains size of 1st bloom filter, tail contains size of
  47     // 2nd bloom filter
  48
  49     m_filter_size = atoi(head.c_str());
  50     m_filter_size_bits = floorLog2(m_filter_size);
  51
  52     m_page_filter_size = atoi(tail.c_str());
  53     m_page_filter_size_bits = floorLog2(m_page_filter_size);
  54
  55     m_filter.resize(m_filter_size);
  56     m_page_filter.resize(m_page_filter_size);
  57     clear();
  58 }
  59
  60 MultiGrainBloomFilter::~MultiGrainBloomFilter()
  61 {
  62 }
  63
  64 void
  65 MultiGrainBloomFilter::clear()
  66 {
  67     for (int i = 0; i < m_filter_size; i++) {
  68         m_filter[i] = 0;
  69     }
  70     for(int i=0; i < m_page_filter_size; ++i){
  71         m_page_filter[i] = 0;
  72     }
  73 }
  74
  75 void
  76 MultiGrainBloomFilter::increment(const Address& addr)
  77 {
  78     // Not used
  79 }
  80
  81
  82 void
  83 MultiGrainBloomFilter::decrement(const Address& addr)
  84 {
  85     // Not used
  86 }
  87
  88 void
  89 MultiGrainBloomFilter::merge(AbstractBloomFilter *other_filter)
  90 {
  91     // TODO
  92 }
  93
  94 void
  95 MultiGrainBloomFilter::set(const Address& addr)
  96 {
  97     int i = get_block_index(addr);
  98     assert(i < m_filter_size);
  99     assert(get_page_index(addr) < m_page_filter_size);
 100     m_filter[i] = 1;
 101     m_page_filter[i] = 1;
 102
 103 }
 104
 105 void
 106 MultiGrainBloomFilter::unset(const Address& addr)
 107 {
 108     // not used
 109 }
 110
 111 bool
 112 MultiGrainBloomFilter::isSet(const Address& addr)
 113 {
 114     int i = get_block_index(addr);
 115     assert(i < m_filter_size);
 116     assert(get_page_index(addr) < m_page_filter_size);
 117     // we have to have both indices set
 118     return (m_filter[i] && m_page_filter[i]);
 119 }
 120
 121 int
 122 MultiGrainBloomFilter::getCount(const Address& addr)
 123 {
 124     // not used
 125     return 0;
 126 }
 127
 128 int
 129 MultiGrainBloomFilter::getTotalCount()
 130 {
 131     int count = 0;
 132
 133     for (int i = 0; i < m_filter_size; i++) {
 134         count += m_filter[i];
 135     }
 136
 137     for(int i=0; i < m_page_filter_size; ++i) {
 138         count += m_page_filter[i] = 0;
 139     }
 140
 141     return count;
 142 }
 143
 144 int
 145 MultiGrainBloomFilter::getIndex(const Address& addr)
 146 {
 147     return 0;
 148     // TODO
 149 }
 150
 151 int
 152 MultiGrainBloomFilter::readBit(const int index)
 153 {
 154     return 0;
 155     // TODO
 156 }
 157
 158 void
 159 MultiGrainBloomFilter::writeBit(const int index, const int value)
 160 {
 161     // TODO
 162 }
 163
 164 void
 165 MultiGrainBloomFilter::print(ostream& out) const
 166 {
 167 }
 168
 169 int
 170 MultiGrainBloomFilter::get_block_index(const Address& addr)
 171 {
 172     // grap a chunk of bits after byte offset
 173     return addr.bitSelect(RubySystem::getBlockSizeBits(),
 174                           RubySystem::getBlockSizeBits() +
 175                           m_filter_size_bits - 1);
 176 }
 177
 178 int
 179 MultiGrainBloomFilter::get_page_index(const Address & addr)
 180 {
 181     int bits = RubySystem::getBlockSizeBits() + m_filter_size_bits - 1;
 182
 183     // grap a chunk of bits after first chunk
 184     return addr.bitSelect(bits, bits + m_page_filter_size_bits - 1);
 185 }
 186
 187
 188
 189