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Diffstat (limited to 'src/base/filters/BloomFilters.py')
-rw-r--r-- | src/base/filters/BloomFilters.py | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/src/base/filters/BloomFilters.py b/src/base/filters/BloomFilters.py new file mode 100644 index 000000000..208b8a97a --- /dev/null +++ b/src/base/filters/BloomFilters.py @@ -0,0 +1,104 @@ +# Copyright (c) 2019 Inria +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions are +# met: redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer; +# redistributions in binary form must reproduce the above copyright +# notice, this list of conditions and the following disclaimer in the +# documentation and/or other materials provided with the distribution; +# neither the name of the copyright holders nor the names of its +# contributors may be used to endorse or promote products derived from +# this software without specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +# +# Authors: Daniel Carvalho + +from m5.params import * +from m5.proxy import * +from m5.SimObject import SimObject + +class BloomFilterBase(SimObject): + type = 'BloomFilterBase' + abstract = True + cxx_header = "base/filters/base.hh" + cxx_class = 'BloomFilter::Base' + + size = Param.Int(4096, "Number of entries in the filter") + + # By default assume that bloom filters are used for 64-byte cache lines + offset_bits = Param.Unsigned(6, "Number of bits in a cache line offset") + + # Most of the filters are booleans, and thus saturate on 1 + threshold = Param.Int(1, "Value at which an entry is considered as set") + +class BloomFilterBlock(BloomFilterBase): + type = 'BloomFilterBlock' + cxx_class = 'BloomFilter::Block' + cxx_header = "base/filters/block_bloom_filter.hh" + + masks_lsbs = VectorParam.Unsigned([Self.offset_bits, + 2 * Self.offset_bits], "Position of the LSB of each mask") + masks_sizes = VectorParam.Unsigned([Self.offset_bits, Self.offset_bits], + "Size, in number of bits, of each mask") + +class BloomFilterBulk(BloomFilterBase): + type = 'BloomFilterBulk' + cxx_class = 'BloomFilter::Bulk' + cxx_header = "base/filters/bulk_bloom_filter.hh" + +class BloomFilterLSBCounting(BloomFilterBase): + type = 'BloomFilterLSBCounting' + cxx_class = 'BloomFilter::LSBCounting' + cxx_header = "base/filters/lsb_counting_bloom_filter.hh" + + # By default use 4-bit saturating counters + max_value = Param.Int(15, "Maximum value of the filter entries") + + # We assume that isSet will return true only when the counter saturates + threshold = Self.max_value + +class BloomFilterMultiBitSel(BloomFilterBase): + type = 'BloomFilterMultiBitSel' + cxx_class = 'BloomFilter::MultiBitSel' + cxx_header = "base/filters/multi_bit_sel_bloom_filter.hh" + + num_hashes = Param.Int(4, "Number of hashes") + threshold = Self.num_hashes + skip_bits = Param.Int(2, "Offset from block number") + is_parallel = Param.Bool(False, "Whether hashing is done in parallel") + +class BloomFilterH3(BloomFilterMultiBitSel): + type = 'BloomFilterH3' + cxx_class = 'BloomFilter::H3' + cxx_header = "base/filters/h3_bloom_filter.hh" + +class BloomFilterMulti(BloomFilterBase): + type = 'BloomFilterMulti' + cxx_class = 'BloomFilter::Multi' + cxx_header = "base/filters/multi_bloom_filter.hh" + + # The base filter should not be used, since this filter is the combination + # of multiple sub-filters, so we use a dummy value + size = 1 + + # By default there are two sub-filters that hash sequential bitfields + filters = VectorParam.BloomFilterBase([ + BloomFilterBlock(size = 4096, masks_lsbs = [6, 12]), + BloomFilterBlock(size = 1024, masks_lsbs = [18, 24])], + "Sub-filters to be combined") + + # By default match this with the number of sub-filters + threshold = 2 |