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Diffstat (limited to 'src/mem/cache/replacement_policies/random_rp.cc')
-rw-r--r-- | src/mem/cache/replacement_policies/random_rp.cc | 71 |
1 files changed, 71 insertions, 0 deletions
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); +} |