From: Daniel R. Carvalho Date: Mon, 12 Mar 2018 11:22:54 +0000 (+0100) Subject: mem-cache: Create BIP Replacement Policy X-Git-Tag: v19.0.0.0~2185 X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=65a703c6bf08217a7ca92d2c3f834de5c8ed98b0;p=gem5.git mem-cache: Create BIP Replacement Policy Implementation of a Bimodal Insertion Policy replacement policy. Change-Id: Ife058d0d4310dbcb35858348006189f0b2bf7c37 Reviewed-on: https://gem5-review.googlesource.com/9003 Reviewed-by: Nikos Nikoleris Maintainer: Nikos Nikoleris --- diff --git a/src/mem/cache/replacement_policies/ReplacementPolicies.py b/src/mem/cache/replacement_policies/ReplacementPolicies.py index 0beb3e60f..7ec728d46 100644 --- a/src/mem/cache/replacement_policies/ReplacementPolicies.py +++ b/src/mem/cache/replacement_policies/ReplacementPolicies.py @@ -50,6 +50,12 @@ class LRURP(BaseReplacementPolicy): cxx_class = 'LRURP' cxx_header = "mem/cache/replacement_policies/lru_rp.hh" +class BIPRP(LRURP): + type = 'BIPRP' + cxx_class = 'BIPRP' + cxx_header = "mem/cache/replacement_policies/bip_rp.hh" + btp = Param.Percent(3, "Percentage of blocks to be inserted as MRU") + class MRURP(BaseReplacementPolicy): type = 'MRURP' cxx_class = 'MRURP' diff --git a/src/mem/cache/replacement_policies/SConscript b/src/mem/cache/replacement_policies/SConscript index 26c450a79..8036ac7cb 100644 --- a/src/mem/cache/replacement_policies/SConscript +++ b/src/mem/cache/replacement_policies/SConscript @@ -33,6 +33,7 @@ Import('*') SimObject('ReplacementPolicies.py') Source('base.cc') +Source('bip_rp.cc') Source('brrip_rp.cc') Source('fifo_rp.cc') Source('lfu_rp.cc') diff --git a/src/mem/cache/replacement_policies/bip_rp.cc b/src/mem/cache/replacement_policies/bip_rp.cc new file mode 100644 index 000000000..215711bb9 --- /dev/null +++ b/src/mem/cache/replacement_policies/bip_rp.cc @@ -0,0 +1,59 @@ +/** + * Copyright (c) 2018 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 + */ + +#include "mem/cache/replacement_policies/bip_rp.hh" + +#include "base/random.hh" +#include "debug/CacheRepl.hh" + +BIPRP::BIPRP(const Params *p) + : LRURP(p), btp(p->btp) +{ +} + +void +BIPRP::reset(CacheBlk *blk) +{ + BaseReplacementPolicy::reset(blk); + + // Blocks are inserted as MRU if lower than btp, LRU otherwise + if (random_mt.random(1, 100) <= btp) { + blk->lastTouchTick = curTick(); + } else { + // Make their timestamps as old as possible, so that they become LRU + blk->lastTouchTick = 0; + } +} + +BIPRP* +BIPRPParams::create() +{ + return new BIPRP(this); +} diff --git a/src/mem/cache/replacement_policies/bip_rp.hh b/src/mem/cache/replacement_policies/bip_rp.hh new file mode 100644 index 000000000..f6e2a9c64 --- /dev/null +++ b/src/mem/cache/replacement_policies/bip_rp.hh @@ -0,0 +1,84 @@ +/** + * Copyright (c) 2018 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 + */ + +/** + * @file + * Declaration of a Bimodal Interval Prediction replacement policy. + * Has a probability of when placing new blocks, placing them as MRU. + * + * Although both LRU and LIP can be seen as specific cases of BIP + * where the bimodal throtle parameter are 1 and 0, respectively, we + * decide not to inherit from it, and do the other way around (inherit + * from LRU) for efficiency reasons. + * + * In the original paper they use btp = 1/32 ~= 3%. + */ + +#ifndef __MEM_CACHE_REPLACEMENT_POLICIES_LIP_RP_HH__ +#define __MEM_CACHE_REPLACEMENT_POLICIES_LIP_RP_HH__ + +#include "mem/cache/replacement_policies/lru_rp.hh" +#include "params/BIPRP.hh" + +class BIPRP : public LRURP +{ + protected: + /** + * Bimodal throtle parameter. Value in the range [0,100] used to decide + * if a new block is inserted at the MRU or LRU position. + */ + const unsigned btp; + + public: + /** Convenience typedef. */ + typedef BIPRPParams Params; + + /** + * Construct and initiliaze this replacement policy. + */ + BIPRP(const Params *p); + + /** + * Destructor. + */ + ~BIPRP() {} + + /** + * Reset replacement data for a block. Used when a block is inserted. + * Sets the insertion tick, and update correspondent replacement data. + * Uses the bimodal throtle parameter to decide whether the new block + * should be inserted as MRU, or LRU. + * + * @param blk Cache block to be reset. + */ + void reset(CacheBlk *blk) override; +}; + +#endif // __MEM_CACHE_REPLACEMENT_POLICIES_LIP_RP_HH__