1/* 2 * Copyright (c) 2007 Mark D. Hill and David A. Wood |
3 * Copyright (c) 2013 Advanced Micro Devices, Inc |
4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are 8 * met: redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer; 10 * redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the --- 14 unchanged lines hidden (view full) --- 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30#ifndef __MEM_RUBY_STRUCTURES_PSEUDOLRUPOLICY_HH__ 31#define __MEM_RUBY_STRUCTURES_PSEUDOLRUPOLICY_HH__ 32 33#include "mem/ruby/structures/AbstractReplacementPolicy.hh" |
34#include "params/PseudoLRUReplacementPolicy.hh" |
35 36/** 37 * Implementation of tree-based pseudo-LRU replacement 38 * 39 * Works for any associativity between 1 and 128. 40 * 41 * Also implements associativities that are not a power of 2 by 42 * ignoring paths that lead to a larger index (i.e. truncating the 43 * tree). Note that when this occurs, the algorithm becomes less 44 * fair, as it will favor indicies in the larger (by index) half of 45 * the associative set. This is most unfair when the nearest power of 46 * 2 is one below the associativy, and most fair when it is one above. 47 */ 48 49class PseudoLRUPolicy : public AbstractReplacementPolicy 50{ 51 public: |
52 typedef PseudoLRUReplacementPolicyParams Params; 53 PseudoLRUPolicy(const Params * p); |
54 ~PseudoLRUPolicy(); 55 56 void touch(int64 set, int64 way, Tick time); 57 int64 getVictim(int64 set) const; 58 59 private: 60 unsigned int m_effective_assoc; /** nearest (to ceiling) power of 2 */ 61 unsigned int m_num_levels; /** number of levels in the tree */ 62 uint64* m_trees; /** bit representation of the 63 * trees, one for each set */ 64}; 65 |
66#endif // __MEM_RUBY_STRUCTURES_PSEUDOLRUPOLICY_HH__ |