PseudoLRUPolicy.hh revision 11061
17008SN/A/* 27008SN/A * Copyright (c) 2007 Mark D. Hill and David A. Wood 310970Sdavid.hashe@amd.com * Copyright (c) 2013 Advanced Micro Devices, Inc 47008SN/A * All rights reserved. 57008SN/A * 67008SN/A * Redistribution and use in source and binary forms, with or without 77008SN/A * modification, are permitted provided that the following conditions are 87008SN/A * met: redistributions of source code must retain the above copyright 97008SN/A * notice, this list of conditions and the following disclaimer; 107008SN/A * redistributions in binary form must reproduce the above copyright 117008SN/A * notice, this list of conditions and the following disclaimer in the 127008SN/A * documentation and/or other materials provided with the distribution; 137008SN/A * neither the name of the copyright holders nor the names of its 147008SN/A * contributors may be used to endorse or promote products derived from 157008SN/A * this software without specific prior written permission. 167008SN/A * 177008SN/A * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 187008SN/A * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 197008SN/A * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 207008SN/A * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 217008SN/A * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 227008SN/A * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 237008SN/A * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 247008SN/A * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 257008SN/A * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 267008SN/A * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 277008SN/A * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 287008SN/A */ 296145SN/A 3010441Snilay@cs.wisc.edu#ifndef __MEM_RUBY_STRUCTURES_PSEUDOLRUPOLICY_HH__ 3110441Snilay@cs.wisc.edu#define __MEM_RUBY_STRUCTURES_PSEUDOLRUPOLICY_HH__ 326145SN/A 3310301Snilay@cs.wisc.edu#include "mem/ruby/structures/AbstractReplacementPolicy.hh" 3410970Sdavid.hashe@amd.com#include "params/PseudoLRUReplacementPolicy.hh" 356145SN/A 366145SN/A/** 376145SN/A * Implementation of tree-based pseudo-LRU replacement 386145SN/A * 396145SN/A * Works for any associativity between 1 and 128. 406145SN/A * 416145SN/A * Also implements associativities that are not a power of 2 by 426145SN/A * ignoring paths that lead to a larger index (i.e. truncating the 436145SN/A * tree). Note that when this occurs, the algorithm becomes less 446145SN/A * fair, as it will favor indicies in the larger (by index) half of 456145SN/A * the associative set. This is most unfair when the nearest power of 466145SN/A * 2 is one below the associativy, and most fair when it is one above. 476145SN/A */ 486145SN/A 497039SN/Aclass PseudoLRUPolicy : public AbstractReplacementPolicy 507039SN/A{ 517039SN/A public: 5210970Sdavid.hashe@amd.com typedef PseudoLRUReplacementPolicyParams Params; 5310970Sdavid.hashe@amd.com PseudoLRUPolicy(const Params * p); 547039SN/A ~PseudoLRUPolicy(); 556145SN/A 5611061Snilay@cs.wisc.edu void touch(int64_t set, int64_t way, Tick time); 5711061Snilay@cs.wisc.edu int64_t getVictim(int64_t set) const; 586145SN/A 597039SN/A private: 607039SN/A unsigned int m_effective_assoc; /** nearest (to ceiling) power of 2 */ 617039SN/A unsigned int m_num_levels; /** number of levels in the tree */ 6211061Snilay@cs.wisc.edu uint64_t* m_trees; /** bit representation of the 637039SN/A * trees, one for each set */ 646145SN/A}; 656145SN/A 6610441Snilay@cs.wisc.edu#endif // __MEM_RUBY_STRUCTURES_PSEUDOLRUPOLICY_HH__ 67