base_set_assoc.hh revision 13752
110263Satgutier@umich.edu/* 212566Snikos.nikoleris@arm.com * Copyright (c) 2012-2014,2017 ARM Limited 310263Satgutier@umich.edu * All rights reserved. 410263Satgutier@umich.edu * 510263Satgutier@umich.edu * The license below extends only to copyright in the software and shall 610263Satgutier@umich.edu * not be construed as granting a license to any other intellectual 710263Satgutier@umich.edu * property including but not limited to intellectual property relating 810263Satgutier@umich.edu * to a hardware implementation of the functionality of the software 910263Satgutier@umich.edu * licensed hereunder. You may use the software subject to the license 1010263Satgutier@umich.edu * terms below provided that you ensure that this notice is replicated 1110263Satgutier@umich.edu * unmodified and in its entirety in all distributions of the software, 1210263Satgutier@umich.edu * modified or unmodified, in source code or in binary form. 1310263Satgutier@umich.edu * 1410263Satgutier@umich.edu * Copyright (c) 2003-2005,2014 The Regents of The University of Michigan 1510263Satgutier@umich.edu * All rights reserved. 1610263Satgutier@umich.edu * 1710263Satgutier@umich.edu * Redistribution and use in source and binary forms, with or without 1810263Satgutier@umich.edu * modification, are permitted provided that the following conditions are 1910263Satgutier@umich.edu * met: redistributions of source code must retain the above copyright 2010263Satgutier@umich.edu * notice, this list of conditions and the following disclaimer; 2110263Satgutier@umich.edu * redistributions in binary form must reproduce the above copyright 2210263Satgutier@umich.edu * notice, this list of conditions and the following disclaimer in the 2310263Satgutier@umich.edu * documentation and/or other materials provided with the distribution; 2410263Satgutier@umich.edu * neither the name of the copyright holders nor the names of its 2510263Satgutier@umich.edu * contributors may be used to endorse or promote products derived from 2610263Satgutier@umich.edu * this software without specific prior written permission. 2710263Satgutier@umich.edu * 2810263Satgutier@umich.edu * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 2910263Satgutier@umich.edu * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 3010263Satgutier@umich.edu * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 3110263Satgutier@umich.edu * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 3210263Satgutier@umich.edu * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 3310263Satgutier@umich.edu * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 3410263Satgutier@umich.edu * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 3510263Satgutier@umich.edu * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 3610263Satgutier@umich.edu * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 3710263Satgutier@umich.edu * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 3810263Satgutier@umich.edu * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 3910263Satgutier@umich.edu * 4010263Satgutier@umich.edu * Authors: Erik Hallnor 4110263Satgutier@umich.edu */ 4210263Satgutier@umich.edu 4310263Satgutier@umich.edu/** 4410263Satgutier@umich.edu * @file 4510263Satgutier@umich.edu * Declaration of a base set associative tag store. 4610263Satgutier@umich.edu */ 4710263Satgutier@umich.edu 4812492Sodanrc@yahoo.com.br#ifndef __MEM_CACHE_TAGS_BASE_SET_ASSOC_HH__ 4912492Sodanrc@yahoo.com.br#define __MEM_CACHE_TAGS_BASE_SET_ASSOC_HH__ 5010263Satgutier@umich.edu 5112728Snikos.nikoleris@arm.com#include <functional> 5212727Snikos.nikoleris@arm.com#include <string> 5312548Sodanrc@yahoo.com.br#include <vector> 5410263Satgutier@umich.edu 5512727Snikos.nikoleris@arm.com#include "base/logging.hh" 5612727Snikos.nikoleris@arm.com#include "base/types.hh" 5711486Snikos.nikoleris@arm.com#include "mem/cache/base.hh" 5813223Sodanrc@yahoo.com.br#include "mem/cache/cache_blk.hh" 5912684Sodanrc@yahoo.com.br#include "mem/cache/replacement_policies/base.hh" 6013225Sodanrc@yahoo.com.br#include "mem/cache/replacement_policies/replaceable_entry.hh" 6110263Satgutier@umich.edu#include "mem/cache/tags/base.hh" 6213219Sodanrc@yahoo.com.br#include "mem/cache/tags/indexing_policies/base.hh" 6313752Sodanrc@yahoo.com.br#include "mem/packet.hh" 6410263Satgutier@umich.edu#include "params/BaseSetAssoc.hh" 6510263Satgutier@umich.edu 6610263Satgutier@umich.edu/** 6713219Sodanrc@yahoo.com.br * A basic cache tag store. 6810263Satgutier@umich.edu * @sa \ref gem5MemorySystem "gem5 Memory System" 6910263Satgutier@umich.edu * 7012600Sodanrc@yahoo.com.br * The BaseSetAssoc placement policy divides the cache into s sets of w 7113219Sodanrc@yahoo.com.br * cache lines (ways). 7210263Satgutier@umich.edu */ 7310263Satgutier@umich.educlass BaseSetAssoc : public BaseTags 7410263Satgutier@umich.edu{ 7510263Satgutier@umich.edu protected: 7610941Sdavid.guillen@arm.com /** The allocatable associativity of the cache (alloc mask). */ 7710941Sdavid.guillen@arm.com unsigned allocAssoc; 7812548Sodanrc@yahoo.com.br 7912548Sodanrc@yahoo.com.br /** The cache blocks. */ 8013220Sodanrc@yahoo.com.br std::vector<CacheBlk> blks; 8112548Sodanrc@yahoo.com.br 8210263Satgutier@umich.edu /** Whether tags and data are accessed sequentially. */ 8310263Satgutier@umich.edu const bool sequentialAccess; 8410263Satgutier@umich.edu 8512600Sodanrc@yahoo.com.br /** Replacement policy */ 8612600Sodanrc@yahoo.com.br BaseReplacementPolicy *replacementPolicy; 8712600Sodanrc@yahoo.com.br 8812600Sodanrc@yahoo.com.br public: 8910263Satgutier@umich.edu /** Convenience typedef. */ 9010263Satgutier@umich.edu typedef BaseSetAssocParams Params; 9110263Satgutier@umich.edu 9210263Satgutier@umich.edu /** 9310263Satgutier@umich.edu * Construct and initialize this tag store. 9410263Satgutier@umich.edu */ 9510263Satgutier@umich.edu BaseSetAssoc(const Params *p); 9610263Satgutier@umich.edu 9710263Satgutier@umich.edu /** 9810263Satgutier@umich.edu * Destructor 9910263Satgutier@umich.edu */ 10012548Sodanrc@yahoo.com.br virtual ~BaseSetAssoc() {}; 10110263Satgutier@umich.edu 10210263Satgutier@umich.edu /** 10313419Sodanrc@yahoo.com.br * Initialize blocks as CacheBlk instances. 10413216Sodanrc@yahoo.com.br */ 10513419Sodanrc@yahoo.com.br void tagsInit() override; 10613216Sodanrc@yahoo.com.br 10713216Sodanrc@yahoo.com.br /** 10812745Sodanrc@yahoo.com.br * This function updates the tags when a block is invalidated. It also 10912745Sodanrc@yahoo.com.br * updates the replacement data. 11012684Sodanrc@yahoo.com.br * 11112684Sodanrc@yahoo.com.br * @param blk The block to invalidate. 11212684Sodanrc@yahoo.com.br */ 11312684Sodanrc@yahoo.com.br void invalidate(CacheBlk *blk) override; 11412684Sodanrc@yahoo.com.br 11512684Sodanrc@yahoo.com.br /** 11610263Satgutier@umich.edu * Access block and update replacement data. May not succeed, in which case 11713418Sodanrc@yahoo.com.br * nullptr is returned. This has all the implications of a cache access and 11813418Sodanrc@yahoo.com.br * should only be used as such. Returns the tag lookup latency as a side 11913418Sodanrc@yahoo.com.br * effect. 12013418Sodanrc@yahoo.com.br * 12110263Satgutier@umich.edu * @param addr The address to find. 12210263Satgutier@umich.edu * @param is_secure True if the target memory space is secure. 12313418Sodanrc@yahoo.com.br * @param lat The latency of the tag lookup. 12410263Satgutier@umich.edu * @return Pointer to the cache block if found. 12510263Satgutier@umich.edu */ 12611870Snikos.nikoleris@arm.com CacheBlk* accessBlock(Addr addr, bool is_secure, Cycles &lat) override 12710263Satgutier@umich.edu { 12813220Sodanrc@yahoo.com.br CacheBlk *blk = findBlock(addr, is_secure); 12910263Satgutier@umich.edu 13010263Satgutier@umich.edu // Access all tags in parallel, hence one in each way. The data side 13110263Satgutier@umich.edu // either accesses all blocks in parallel, or one block sequentially on 13210263Satgutier@umich.edu // a hit. Sequential access with a miss doesn't access data. 13310941Sdavid.guillen@arm.com tagAccesses += allocAssoc; 13410263Satgutier@umich.edu if (sequentialAccess) { 13511484Snikos.nikoleris@arm.com if (blk != nullptr) { 13610263Satgutier@umich.edu dataAccesses += 1; 13710263Satgutier@umich.edu } 13810263Satgutier@umich.edu } else { 13910941Sdavid.guillen@arm.com dataAccesses += allocAssoc; 14010263Satgutier@umich.edu } 14110263Satgutier@umich.edu 14213418Sodanrc@yahoo.com.br // If a cache hit 14311484Snikos.nikoleris@arm.com if (blk != nullptr) { 14412684Sodanrc@yahoo.com.br // Update number of references to accessed block 14512684Sodanrc@yahoo.com.br blk->refCount++; 14612684Sodanrc@yahoo.com.br 14712600Sodanrc@yahoo.com.br // Update replacement data of accessed block 14812684Sodanrc@yahoo.com.br replacementPolicy->touch(blk->replacementData); 14910263Satgutier@umich.edu } 15010263Satgutier@umich.edu 15113418Sodanrc@yahoo.com.br // The tag lookup latency is the same for a hit or a miss 15213418Sodanrc@yahoo.com.br lat = lookupLatency; 15313418Sodanrc@yahoo.com.br 15410263Satgutier@umich.edu return blk; 15510263Satgutier@umich.edu } 15610263Satgutier@umich.edu 15710263Satgutier@umich.edu /** 15812744Sodanrc@yahoo.com.br * Find replacement victim based on address. The list of evicted blocks 15912744Sodanrc@yahoo.com.br * only contains the victim. 16012600Sodanrc@yahoo.com.br * 16112600Sodanrc@yahoo.com.br * @param addr Address to find a victim for. 16212746Sodanrc@yahoo.com.br * @param is_secure True if the target memory space is secure. 16312744Sodanrc@yahoo.com.br * @param evict_blks Cache blocks to be evicted. 16412600Sodanrc@yahoo.com.br * @return Cache block to be replaced. 16510263Satgutier@umich.edu */ 16612746Sodanrc@yahoo.com.br CacheBlk* findVictim(Addr addr, const bool is_secure, 16712746Sodanrc@yahoo.com.br std::vector<CacheBlk*>& evict_blks) const override 16810263Satgutier@umich.edu { 16913219Sodanrc@yahoo.com.br // Get possible entries to be victimized 17013219Sodanrc@yahoo.com.br const std::vector<ReplaceableEntry*> entries = 17113219Sodanrc@yahoo.com.br indexingPolicy->getPossibleEntries(addr); 17212684Sodanrc@yahoo.com.br 17312600Sodanrc@yahoo.com.br // Choose replacement victim from replacement candidates 17412684Sodanrc@yahoo.com.br CacheBlk* victim = static_cast<CacheBlk*>(replacementPolicy->getVictim( 17513219Sodanrc@yahoo.com.br entries)); 17612684Sodanrc@yahoo.com.br 17712744Sodanrc@yahoo.com.br // There is only one eviction for this replacement 17812744Sodanrc@yahoo.com.br evict_blks.push_back(victim); 17912744Sodanrc@yahoo.com.br 18012684Sodanrc@yahoo.com.br return victim; 18112600Sodanrc@yahoo.com.br } 18210263Satgutier@umich.edu 18312600Sodanrc@yahoo.com.br /** 18412636Sodanrc@yahoo.com.br * Insert the new block into the cache and update replacement data. 18512636Sodanrc@yahoo.com.br * 18613752Sodanrc@yahoo.com.br * @param pkt Packet holding the address to update 18710263Satgutier@umich.edu * @param blk The block to update. 18810263Satgutier@umich.edu */ 18913752Sodanrc@yahoo.com.br void insertBlock(const PacketPtr pkt, CacheBlk *blk) override 19012636Sodanrc@yahoo.com.br { 19112636Sodanrc@yahoo.com.br // Insert block 19213752Sodanrc@yahoo.com.br BaseTags::insertBlock(pkt, blk); 19310274Smitch.hayenga@arm.com 19412745Sodanrc@yahoo.com.br // Increment tag counter 19512745Sodanrc@yahoo.com.br tagsInUse++; 19612745Sodanrc@yahoo.com.br 19712636Sodanrc@yahoo.com.br // Update replacement policy 19812684Sodanrc@yahoo.com.br replacementPolicy->reset(blk->replacementData); 19912636Sodanrc@yahoo.com.br } 20010263Satgutier@umich.edu 20110263Satgutier@umich.edu /** 20210941Sdavid.guillen@arm.com * Limit the allocation for the cache ways. 20310941Sdavid.guillen@arm.com * @param ways The maximum number of ways available for replacement. 20410941Sdavid.guillen@arm.com */ 20511169Sandreas.hansson@arm.com virtual void setWayAllocationMax(int ways) override 20610941Sdavid.guillen@arm.com { 20710941Sdavid.guillen@arm.com fatal_if(ways < 1, "Allocation limit must be greater than zero"); 20810941Sdavid.guillen@arm.com allocAssoc = ways; 20910941Sdavid.guillen@arm.com } 21010941Sdavid.guillen@arm.com 21110941Sdavid.guillen@arm.com /** 21210941Sdavid.guillen@arm.com * Get the way allocation mask limit. 21310941Sdavid.guillen@arm.com * @return The maximum number of ways available for replacement. 21410941Sdavid.guillen@arm.com */ 21511169Sandreas.hansson@arm.com virtual int getWayAllocationMax() const override 21610941Sdavid.guillen@arm.com { 21710941Sdavid.guillen@arm.com return allocAssoc; 21810941Sdavid.guillen@arm.com } 21910941Sdavid.guillen@arm.com 22010941Sdavid.guillen@arm.com /** 22113219Sodanrc@yahoo.com.br * Regenerate the block address from the tag and indexing location. 22212574Sodanrc@yahoo.com.br * 22312574Sodanrc@yahoo.com.br * @param block The block. 22412574Sodanrc@yahoo.com.br * @return the block address. 22510263Satgutier@umich.edu */ 22612574Sodanrc@yahoo.com.br Addr regenerateBlkAddr(const CacheBlk* blk) const override 22710263Satgutier@umich.edu { 22813219Sodanrc@yahoo.com.br return indexingPolicy->regenerateAddr(blk->tag, blk); 22910263Satgutier@umich.edu } 23010263Satgutier@umich.edu 23112728Snikos.nikoleris@arm.com void forEachBlk(std::function<void(CacheBlk &)> visitor) override { 23212728Snikos.nikoleris@arm.com for (CacheBlk& blk : blks) { 23312728Snikos.nikoleris@arm.com visitor(blk); 23412728Snikos.nikoleris@arm.com } 23512728Snikos.nikoleris@arm.com } 23610263Satgutier@umich.edu 23712728Snikos.nikoleris@arm.com bool anyBlk(std::function<bool(CacheBlk &)> visitor) override { 23812679Sodanrc@yahoo.com.br for (CacheBlk& blk : blks) { 23912728Snikos.nikoleris@arm.com if (visitor(blk)) { 24012728Snikos.nikoleris@arm.com return true; 24112728Snikos.nikoleris@arm.com } 24210263Satgutier@umich.edu } 24312728Snikos.nikoleris@arm.com return false; 24410263Satgutier@umich.edu } 24510263Satgutier@umich.edu}; 24610263Satgutier@umich.edu 24712492Sodanrc@yahoo.com.br#endif //__MEM_CACHE_TAGS_BASE_SET_ASSOC_HH__ 248