src/mem/cache/replacement_policies/ReplacementPolicies.py

# Copyright (c) 2018-2020 Inria
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from m5.params import *
from m5.proxy import *
from m5.SimObject import SimObject

class BaseReplacementPolicy(SimObject):
    type = 'BaseReplacementPolicy'
    abstract = True
    cxx_class = 'gem5::replacement_policy::Base'
    cxx_header = "mem/cache/replacement_policies/base.hh"

class DuelingRP(BaseReplacementPolicy):
    type = 'DuelingRP'
    cxx_class = 'gem5::replacement_policy::Dueling'
    cxx_header = "mem/cache/replacement_policies/dueling_rp.hh"

    constituency_size = Param.Unsigned(
        "The size of a region containing one sample")
    team_size = Param.Unsigned(
        "Number of entries in a sampling set that belong to a team")
    replacement_policy_a = Param.BaseReplacementPolicy(
        "Sub-replacement policy A")
    replacement_policy_b = Param.BaseReplacementPolicy(
        "Sub-replacement policy B")

class FIFORP(BaseReplacementPolicy):
    type = 'FIFORP'
    cxx_class = 'gem5::replacement_policy::FIFO'
    cxx_header = "mem/cache/replacement_policies/fifo_rp.hh"

class SecondChanceRP(FIFORP):
    type = 'SecondChanceRP'
    cxx_class = 'gem5::replacement_policy::SecondChance'
    cxx_header = "mem/cache/replacement_policies/second_chance_rp.hh"

class LFURP(BaseReplacementPolicy):
    type = 'LFURP'
    cxx_class = 'gem5::replacement_policy::LFU'
    cxx_header = "mem/cache/replacement_policies/lfu_rp.hh"

class LRURP(BaseReplacementPolicy):
    type = 'LRURP'
    cxx_class = 'gem5::replacement_policy::LRU'
    cxx_header = "mem/cache/replacement_policies/lru_rp.hh"

class BIPRP(LRURP):
    type = 'BIPRP'
    cxx_class = 'gem5::replacement_policy::BIP'
    cxx_header = "mem/cache/replacement_policies/bip_rp.hh"
    btp = Param.Percent(3, "Percentage of blocks to be inserted as MRU")

class LIPRP(BIPRP):
    btp = 0

class MRURP(BaseReplacementPolicy):
    type = 'MRURP'
    cxx_class = 'gem5::replacement_policy::MRU'
    cxx_header = "mem/cache/replacement_policies/mru_rp.hh"

class RandomRP(BaseReplacementPolicy):
    type = 'RandomRP'
    cxx_class = 'gem5::replacement_policy::Random'
    cxx_header = "mem/cache/replacement_policies/random_rp.hh"

class BRRIPRP(BaseReplacementPolicy):
    type = 'BRRIPRP'
    cxx_class = 'gem5::replacement_policy::BRRIP'
    cxx_header = "mem/cache/replacement_policies/brrip_rp.hh"
    num_bits = Param.Int(2, "Number of bits per RRPV")
    hit_priority = Param.Bool(False,
        "Prioritize evicting blocks that havent had a hit recently")
    btp = Param.Percent(3,
        "Percentage of blocks to be inserted with long RRPV")

class RRIPRP(BRRIPRP):
    btp = 100

class DRRIPRP(DuelingRP):
    # The constituency_size and the team_size must be manually provided, where:
    #     constituency_size = num_cache_entries /
    #         (num_dueling_sets * num_entries_per_set)
    # The paper assumes that:
    #     num_dueling_sets = 32
    #     team_size = num_entries_per_set
    replacement_policy_a = BRRIPRP()
    replacement_policy_b = RRIPRP()

class NRURP(BRRIPRP):
    btp = 100
    num_bits = 1

class SHiPRP(BRRIPRP):
    type = 'SHiPRP'
    abstract = True
    cxx_class = 'gem5::replacement_policy::SHiP'
    cxx_header = "mem/cache/replacement_policies/ship_rp.hh"

    shct_size = Param.Unsigned(16384, "Number of SHCT entries")
    # By default any value greater than 0 is enough to change insertion policy
    insertion_threshold = Param.Percent(1,
        "Percentage at which an entry changes insertion policy")
    # Always make hits mark entries as last to be evicted
    hit_priority = True
    # Let the predictor decide when to change insertion policy
    btp = 0

class SHiPMemRP(SHiPRP):
    type = 'SHiPMemRP'
    cxx_class = 'gem5::replacement_policy::SHiPMem'
    cxx_header = "mem/cache/replacement_policies/ship_rp.hh"

class SHiPPCRP(SHiPRP):
    type = 'SHiPPCRP'
    cxx_class = 'gem5::replacement_policy::SHiPPC'
    cxx_header = "mem/cache/replacement_policies/ship_rp.hh"

class TreePLRURP(BaseReplacementPolicy):
    type = 'TreePLRURP'
    cxx_class = 'gem5::replacement_policy::TreePLRU'
    cxx_header = "mem/cache/replacement_policies/tree_plru_rp.hh"
    num_leaves = Param.Int(Parent.assoc, "Number of leaves in each tree")

class WeightedLRURP(LRURP):
    type = "WeightedLRURP"
    cxx_class = 'gem5::replacement_policy::WeightedLRU'
    cxx_header = "mem/cache/replacement_policies/weighted_lru_rp.hh"