| /* |
| * Copyright (c) 2007 Mark D. Hill and David A. Wood |
| * 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. |
| */ |
| |
| #ifndef __MEM_RUBY_SYSTEM_LRUPOLICY_HH__ |
| #define __MEM_RUBY_SYSTEM_LRUPOLICY_HH__ |
| |
| #include "mem/ruby/structures/AbstractReplacementPolicy.hh" |
| |
| /* Simple true LRU replacement policy */ |
| |
| class LRUPolicy : public AbstractReplacementPolicy |
| { |
| public: |
| LRUPolicy(int64 num_sets, int64 assoc); |
| ~LRUPolicy(); |
| |
| void touch(int64 set, int64 way, Tick time); |
| int64 getVictim(int64 set) const; |
| }; |
| |
| inline |
| LRUPolicy::LRUPolicy(int64 num_sets, int64 assoc) |
| : AbstractReplacementPolicy(num_sets, assoc) |
| { |
| } |
| |
| inline |
| LRUPolicy::~LRUPolicy() |
| { |
| } |
| |
| inline void |
| LRUPolicy::touch(int64 set, int64 index, Tick time) |
| { |
| assert(index >= 0 && index < m_assoc); |
| assert(set >= 0 && set < m_num_sets); |
| |
| m_last_ref_ptr[set][index] = time; |
| } |
| |
| inline int64 |
| LRUPolicy::getVictim(int64 set) const |
| { |
| // assert(m_assoc != 0); |
| Tick time, smallest_time; |
| int64 smallest_index; |
| |
| smallest_index = 0; |
| smallest_time = m_last_ref_ptr[set][0]; |
| |
| for (unsigned i = 0; i < m_assoc; i++) { |
| time = m_last_ref_ptr[set][i]; |
| // assert(m_cache[cacheSet][i].m_Permission != |
| // AccessPermission_NotPresent); |
| |
| if (time < smallest_time) { |
| smallest_index = i; |
| smallest_time = time; |
| } |
| } |
| |
| // DEBUG_EXPR(CACHE_COMP, MedPrio, cacheSet); |
| // DEBUG_EXPR(CACHE_COMP, MedPrio, smallest_index); |
| // DEBUG_EXPR(CACHE_COMP, MedPrio, m_cache[cacheSet][smallest_index]); |
| // DEBUG_EXPR(CACHE_COMP, MedPrio, *this); |
| |
| return smallest_index; |
| } |
| |
| #endif // __MEM_RUBY_SYSTEM_LRUPOLICY_HH__ |