diff options
Diffstat (limited to 'src/mem/cache/replacement_policies')
| -rw-r--r-- | src/mem/cache/replacement_policies/ReplacementPolicies.py | 46 | ||||
| -rw-r--r-- | src/mem/cache/replacement_policies/SConscript | 37 | ||||
| -rw-r--r-- | src/mem/cache/replacement_policies/base.cc | 66 | ||||
| -rw-r--r-- | src/mem/cache/replacement_policies/base.hh | 105 | ||||
| -rw-r--r-- | src/mem/cache/replacement_policies/lru_rp.cc | 87 | ||||
| -rw-r--r-- | src/mem/cache/replacement_policies/lru_rp.hh | 84 | ||||
| -rw-r--r-- | src/mem/cache/replacement_policies/random_rp.cc | 71 | ||||
| -rw-r--r-- | src/mem/cache/replacement_policies/random_rp.hh | 67 |
8 files changed, 563 insertions, 0 deletions
diff --git a/src/mem/cache/replacement_policies/ReplacementPolicies.py b/src/mem/cache/replacement_policies/ReplacementPolicies.py new file mode 100644 index 000000000..64743819b --- /dev/null +++ b/src/mem/cache/replacement_policies/ReplacementPolicies.py @@ -0,0 +1,46 @@ +# 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 + +from m5.params import * +from m5.proxy import * +from m5.SimObject import SimObject + +class BaseReplacementPolicy(SimObject): + type = 'BaseReplacementPolicy' + abstract = True + cxx_header = "mem/cache/replacement_policies/base.hh" + +class LRURP(BaseReplacementPolicy): + type = 'LRURP' + cxx_class = 'LRURP' + cxx_header = "mem/cache/replacement_policies/lru_rp.hh" + +class RandomRP(BaseReplacementPolicy): + type = 'RandomRP' + cxx_class = 'RandomRP' + cxx_header = "mem/cache/replacement_policies/random_rp.hh" diff --git a/src/mem/cache/replacement_policies/SConscript b/src/mem/cache/replacement_policies/SConscript new file mode 100644 index 000000000..c3c89923f --- /dev/null +++ b/src/mem/cache/replacement_policies/SConscript @@ -0,0 +1,37 @@ +# -*- mode:python -*- + +# 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 + +Import('*') + +SimObject('ReplacementPolicies.py') + +Source('base.cc') +Source('lru_rp.cc') +Source('random_rp.cc') diff --git a/src/mem/cache/replacement_policies/base.cc b/src/mem/cache/replacement_policies/base.cc new file mode 100644 index 000000000..c422a75d8 --- /dev/null +++ b/src/mem/cache/replacement_policies/base.cc @@ -0,0 +1,66 @@ +/** + * 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 common base class for cache replacement policy objects. + * In general replacement policies try to use invalid entries as victims, + * and if no such blocks exist the replacement policy is applied. + */ + +#include "mem/cache/replacement_policies/base.hh" + +BaseReplacementPolicy::BaseReplacementPolicy(const Params *p) + : SimObject(p) +{ +} + +void +BaseReplacementPolicy::touch(CacheBlk *blk) +{ + // Inform block has been touched + blk->isTouched = true; + + // Update frequency counter + blk->refCount++; +} + +void +BaseReplacementPolicy::reset(CacheBlk *blk) +{ + // Inform block has been touched + blk->isTouched = true; + + // Set insertion tick + blk->tickInserted = curTick(); + + // Reset frequency counter + blk->refCount = 0; +} diff --git a/src/mem/cache/replacement_policies/base.hh b/src/mem/cache/replacement_policies/base.hh new file mode 100644 index 000000000..383f3f01a --- /dev/null +++ b/src/mem/cache/replacement_policies/base.hh @@ -0,0 +1,105 @@ +/** + * 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 + */ + +#ifndef __MEM_CACHE_REPLACEMENT_POLICIES_BASE_HH__ +#define __MEM_CACHE_REPLACEMENT_POLICIES_BASE_HH__ + +#include "mem/cache/base.hh" +#include "mem/cache/blk.hh" +#include "params/BaseReplacementPolicy.hh" +#include "sim/sim_object.hh" + +/** + * Replacement candidates as chosen by the indexing policy. + * + * The base functions touch() and reset() must be called by all subclasses + * that override them. + * + * @todo + * Currently the replacement candidates are simply the cache blocks + * derived from the possible placement locations of an address, as + * defined by the getPossibleLocations() from BaseTags. In a future + * patch it should be an inheritable class to allow the replacement + * policies to be used with any table-like structure that needs to + * replace its entries. + */ +typedef std::vector<CacheBlk*> ReplacementCandidates; + +/** + * A common base class of cache replacement policy objects. + */ +class BaseReplacementPolicy : public SimObject +{ + public: + /** + * Convenience typedef. + */ + typedef BaseReplacementPolicyParams Params; + + /** + * Construct and initiliaze this replacement policy. + */ + BaseReplacementPolicy(const Params *p); + + /** + * Destructor. + */ + virtual ~BaseReplacementPolicy() {} + + /** + * Touch a block to update its replacement data. + * Updates number of references. + * + * This base function must be called by all subclasses that override it. + * + * @param blk Cache block to be touched. + */ + virtual void touch(CacheBlk *blk); + + /** + * Reset replacement data for a block. Used when a block is inserted. + * Sets the insertion tick, and update number of references. + * + * This base function must be called by all subclasses that override it. + * + * @param blk Cache block to be reset. + */ + virtual void reset(CacheBlk *blk); + + /** + * Find replacement victim among candidates. + * + * @param candidates Replacement candidates, selected by indexing policy. + * @return Cache block to be replaced. + */ + virtual CacheBlk* getVictim(const ReplacementCandidates& candidates) = 0; +}; + +#endif // __MEM_CACHE_REPLACEMENT_POLICIES_BASE_HH__ diff --git a/src/mem/cache/replacement_policies/lru_rp.cc b/src/mem/cache/replacement_policies/lru_rp.cc new file mode 100644 index 000000000..b2fa20b6f --- /dev/null +++ b/src/mem/cache/replacement_policies/lru_rp.cc @@ -0,0 +1,87 @@ +/** + * 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/lru_rp.hh" + +#include "debug/CacheRepl.hh" + +LRURP::LRURP(const Params *p) + : BaseReplacementPolicy(p) +{ +} + +void +LRURP::touch(CacheBlk *blk) +{ + BaseReplacementPolicy::touch(blk); + + // Update last touch timestamp + blk->lastTouchTick = curTick(); +} + +void +LRURP::reset(CacheBlk *blk) +{ + BaseReplacementPolicy::reset(blk); + + // Set last touch timestamp + blk->lastTouchTick = blk->tickInserted; +} + +CacheBlk* +LRURP::getVictim(const ReplacementCandidates& candidates) +{ + // There must be at least one replacement candidate + assert(candidates.size() > 0); + + // Visit all candidates to find victim + CacheBlk* blk = candidates[0]; + for (const auto& candidate : candidates) { + // Stop iteration if found an invalid block + if (!candidate->isValid()) { + blk = candidate; + break; + // Update victim block if necessary + } else if (candidate->lastTouchTick < blk->lastTouchTick) { + blk = candidate; + } + } + + DPRINTF(CacheRepl, "set %x, way %x: selecting blk for replacement\n", + blk->set, blk->way); + + return blk; +} + +LRURP* +LRURPParams::create() +{ + return new LRURP(this); +} diff --git a/src/mem/cache/replacement_policies/lru_rp.hh b/src/mem/cache/replacement_policies/lru_rp.hh new file mode 100644 index 000000000..3e5efe61f --- /dev/null +++ b/src/mem/cache/replacement_policies/lru_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 Least Recently Used replacement policy. + * The victim is chosen using the timestamp. The timestamp may be true or + * pseudo, depending on the quantity of bits allocated for that. + */ + +#ifndef __MEM_CACHE_REPLACEMENT_POLICIES_LRU_RP_HH__ +#define __MEM_CACHE_REPLACEMENT_POLICIES_LRU_RP_HH__ + +#include "mem/cache/replacement_policies/base.hh" +#include "params/LRURP.hh" + +class LRURP : public BaseReplacementPolicy +{ + public: + /** Convenience typedef. */ + typedef LRURPParams Params; + + /** + * Construct and initiliaze this replacement policy. + */ + LRURP(const Params *p); + + /** + * Destructor. + */ + ~LRURP() {} + + /** + * Touch a block to update its last touch tick. + * + * @param blk Cache block to be touched. + */ + void touch(CacheBlk *blk); + + /** + * Reset replacement data for a block. Used when a block is inserted. + * Sets its last touch tick as the current tick. + * + * @param blk Cache block to be reset. + */ + void reset(CacheBlk *blk); + + /** + * Find replacement victim using LRU timestamps. + * + * @param candidates Replacement candidates, selected by indexing policy. + * @return Cache block to be replaced. + */ + CacheBlk* getVictim(const ReplacementCandidates& candidates) override; +}; + +#endif // __MEM_CACHE_REPLACEMENT_POLICIES_LRU_RP_HH__ diff --git a/src/mem/cache/replacement_policies/random_rp.cc b/src/mem/cache/replacement_policies/random_rp.cc new file mode 100644 index 000000000..1c54bdac6 --- /dev/null +++ b/src/mem/cache/replacement_policies/random_rp.cc @@ -0,0 +1,71 @@ +/** + * 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/random_rp.hh" + +#include "base/random.hh" +#include "debug/CacheRepl.hh" + +RandomRP::RandomRP(const Params *p) + : BaseReplacementPolicy(p) +{ +} + +CacheBlk* +RandomRP::getVictim(const ReplacementCandidates& candidates) +{ + // There must be at least one replacement candidate + assert(candidates.size() > 0); + + // Choose one candidate at random + CacheBlk* blk = candidates[random_mt.random<unsigned>(0, + candidates.size() - 1)]; + + // Visit all candidates to find an invalid entry + for (const auto& candidate : candidates) { + // Give priority to victimise invalid entries + if (!candidate->isValid()){ + blk = candidate; + break; + } + } + + // If no invalid blocks were found, choose one of the candidates randomly + DPRINTF(CacheRepl, "set %x, way %x: selecting blk for replacement\n", + blk->set, blk->way); + + return blk; +} + +RandomRP* +RandomRPParams::create() +{ + return new RandomRP(this); +} diff --git a/src/mem/cache/replacement_policies/random_rp.hh b/src/mem/cache/replacement_policies/random_rp.hh new file mode 100644 index 000000000..338b26ff2 --- /dev/null +++ b/src/mem/cache/replacement_policies/random_rp.hh @@ -0,0 +1,67 @@ +/** + * 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 random replacement policy. + * The victim is chosen at random, if there are no invalid entries. + */ + +#ifndef __MEM_CACHE_REPLACEMENT_POLICIES_RANDOM_RP_HH__ +#define __MEM_CACHE_REPLACEMENT_POLICIES_RANDOM_RP_HH__ + +#include "mem/cache/replacement_policies/base.hh" +#include "params/RandomRP.hh" + +class RandomRP : public BaseReplacementPolicy +{ + public: + /** Convenience typedef. */ + typedef RandomRPParams Params; + + /** + * Construct and initiliaze this replacement policy. + */ + RandomRP(const Params *p); + + /** + * Destructor. + */ + ~RandomRP() {} + + /** + * Find replacement victim at random. + * @param candidates Replacement candidates, selected by indexing policy. + * @return Cache block to be replaced. + */ + CacheBlk* getVictim(const ReplacementCandidates& candidates) override; +}; + +#endif // __MEM_CACHE_REPLACEMENT_POLICIES_RANDOM_RP_HH__ |