| /* |
| * Copyright (c) 2013-2015 Advanced Micro Devices, Inc. |
| * All rights reserved. |
| * |
| * For use for simulation and test purposes only |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright notice, |
| * this list of conditions and the following disclaimer. |
| * |
| * 2. 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. |
| * |
| * 3. Neither the name of the copyright holder 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 HOLDER 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: Sooraj Puthoor |
| */ |
| |
| #ifndef __MEM_RUBY_SYSTEM_WEIGHTEDLRUPOLICY_HH__ |
| #define __MEM_RUBY_SYSTEM_WEIGHTEDLRUPOLICY_HH__ |
| |
| #include "mem/cache/replacement_policies/base.hh" |
| #include "mem/ruby/structures/CacheMemory.hh" |
| #include "params/WeightedLRUReplacementPolicy.hh" |
| |
| /* Simple true LRU replacement policy */ |
| |
| class WeightedLRUPolicy : public BaseReplacementPolicy |
| { |
| protected: |
| /** Weighted LRU implementation of replacement data. */ |
| struct WeightedLRUReplData : ReplacementData |
| { |
| /** pointer for last occupancy */ |
| int last_occ_ptr; |
| |
| /** Tick on which the entry was last touched. */ |
| Tick last_touch_tick; |
| |
| /** |
| * Default constructor. Invalidate data. |
| */ |
| WeightedLRUReplData() : ReplacementData(), |
| last_occ_ptr(0), last_touch_tick(0) {} |
| }; |
| public: |
| typedef WeightedLRUReplacementPolicyParams Params; |
| WeightedLRUPolicy(const Params* p); |
| ~WeightedLRUPolicy() {} |
| |
| /** |
| * Invalidate replacement data to set it as the next probable victim. |
| * Sets its last touch tick as the starting tick. |
| * |
| * @param replacement_data Replacement data to be invalidated. |
| */ |
| void invalidate(const std::shared_ptr<ReplacementData>& replacement_data) |
| const override; |
| /** |
| * Touch an entry to update its replacement data. |
| * Sets its last touch tick as the current tick. |
| * |
| * @param replacement_data Replacement data to be touched. |
| */ |
| void touch(const std::shared_ptr<ReplacementData>& |
| replacement_data) const override; |
| void touch(const std::shared_ptr<ReplacementData>& replacement_data, |
| int occupancy) const; |
| |
| /** |
| * Reset replacement data. Used when an entry is inserted. |
| * Sets its last touch tick as the current tick. |
| * |
| * @param replacement_data Replacement data to be reset. |
| */ |
| void reset(const std::shared_ptr<ReplacementData>& replacement_data) const |
| override; |
| |
| /** |
| * Instantiate a replacement data entry. |
| * |
| * @return A shared pointer to the new replacement data. |
| */ |
| std::shared_ptr<ReplacementData> instantiateEntry() override; |
| |
| /** |
| * Find replacement victim using weight. |
| * |
| * @param candidates Replacement candidates, selected by indexing policy. |
| * @return Replacement entry to be replaced. |
| */ |
| ReplaceableEntry* getVictim(const ReplacementCandidates& |
| candidates) const override; |
| }; |
| |
| #endif // __MEM_RUBY_SYSTEM_WeightedLRUPolicy_HH__ |