base_set_assoc.hh revision 12679
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 5110263Satgutier@umich.edu#include <cassert> 5210263Satgutier@umich.edu#include <cstring> 5312548Sodanrc@yahoo.com.br#include <memory> 5412548Sodanrc@yahoo.com.br#include <vector> 5510263Satgutier@umich.edu 5611486Snikos.nikoleris@arm.com#include "mem/cache/base.hh" 5711486Snikos.nikoleris@arm.com#include "mem/cache/blk.hh" 5810263Satgutier@umich.edu#include "mem/cache/tags/base.hh" 5910263Satgutier@umich.edu#include "mem/cache/tags/cacheset.hh" 6010263Satgutier@umich.edu#include "mem/packet.hh" 6110263Satgutier@umich.edu#include "params/BaseSetAssoc.hh" 6210263Satgutier@umich.edu 6310263Satgutier@umich.edu/** 6410263Satgutier@umich.edu * A BaseSetAssoc cache tag store. 6510263Satgutier@umich.edu * @sa \ref gem5MemorySystem "gem5 Memory System" 6610263Satgutier@umich.edu * 6712600Sodanrc@yahoo.com.br * The BaseSetAssoc placement policy divides the cache into s sets of w 6812600Sodanrc@yahoo.com.br * cache lines (ways). A cache line is mapped onto a set, and can be placed 6912600Sodanrc@yahoo.com.br * into any of the ways of this set. 7010263Satgutier@umich.edu */ 7110263Satgutier@umich.educlass BaseSetAssoc : public BaseTags 7210263Satgutier@umich.edu{ 7310263Satgutier@umich.edu public: 7410263Satgutier@umich.edu /** Typedef the block type used in this tag store. */ 7510263Satgutier@umich.edu typedef CacheBlk BlkType; 7610263Satgutier@umich.edu /** Typedef the set type used in this tag store. */ 7710263Satgutier@umich.edu typedef CacheSet<CacheBlk> SetType; 7810263Satgutier@umich.edu 7910263Satgutier@umich.edu protected: 8010263Satgutier@umich.edu /** The associativity of the cache. */ 8110263Satgutier@umich.edu const unsigned assoc; 8210941Sdavid.guillen@arm.com /** The allocatable associativity of the cache (alloc mask). */ 8310941Sdavid.guillen@arm.com unsigned allocAssoc; 8412548Sodanrc@yahoo.com.br 8512548Sodanrc@yahoo.com.br /** The cache blocks. */ 8612548Sodanrc@yahoo.com.br std::vector<BlkType> blks; 8712548Sodanrc@yahoo.com.br 8810263Satgutier@umich.edu /** The number of sets in the cache. */ 8910263Satgutier@umich.edu const unsigned numSets; 9012548Sodanrc@yahoo.com.br 9110263Satgutier@umich.edu /** Whether tags and data are accessed sequentially. */ 9210263Satgutier@umich.edu const bool sequentialAccess; 9310263Satgutier@umich.edu 9410263Satgutier@umich.edu /** The cache sets. */ 9512548Sodanrc@yahoo.com.br std::vector<SetType> sets; 9610263Satgutier@umich.edu 9710263Satgutier@umich.edu /** The amount to shift the address to get the set. */ 9810263Satgutier@umich.edu int setShift; 9910263Satgutier@umich.edu /** The amount to shift the address to get the tag. */ 10010263Satgutier@umich.edu int tagShift; 10110263Satgutier@umich.edu /** Mask out all bits that aren't part of the set index. */ 10210263Satgutier@umich.edu unsigned setMask; 10310263Satgutier@umich.edu 10412600Sodanrc@yahoo.com.br /** Replacement policy */ 10512600Sodanrc@yahoo.com.br BaseReplacementPolicy *replacementPolicy; 10612600Sodanrc@yahoo.com.br 10712600Sodanrc@yahoo.com.br public: 10810263Satgutier@umich.edu 10910263Satgutier@umich.edu /** Convenience typedef. */ 11010263Satgutier@umich.edu typedef BaseSetAssocParams Params; 11110263Satgutier@umich.edu 11210263Satgutier@umich.edu /** 11310263Satgutier@umich.edu * Construct and initialize this tag store. 11410263Satgutier@umich.edu */ 11510263Satgutier@umich.edu BaseSetAssoc(const Params *p); 11610263Satgutier@umich.edu 11710263Satgutier@umich.edu /** 11810263Satgutier@umich.edu * Destructor 11910263Satgutier@umich.edu */ 12012548Sodanrc@yahoo.com.br virtual ~BaseSetAssoc() {}; 12110263Satgutier@umich.edu 12210263Satgutier@umich.edu /** 12310941Sdavid.guillen@arm.com * Find the cache block given set and way 12410941Sdavid.guillen@arm.com * @param set The set of the block. 12510941Sdavid.guillen@arm.com * @param way The way of the block. 12610941Sdavid.guillen@arm.com * @return The cache block. 12710941Sdavid.guillen@arm.com */ 12811169Sandreas.hansson@arm.com CacheBlk *findBlockBySetAndWay(int set, int way) const override; 12910941Sdavid.guillen@arm.com 13010941Sdavid.guillen@arm.com /** 13110263Satgutier@umich.edu * Access block and update replacement data. May not succeed, in which case 13211484Snikos.nikoleris@arm.com * nullptr is returned. This has all the implications of a cache 13310263Satgutier@umich.edu * access and should only be used as such. Returns the access latency as a 13410263Satgutier@umich.edu * side effect. 13510263Satgutier@umich.edu * @param addr The address to find. 13610263Satgutier@umich.edu * @param is_secure True if the target memory space is secure. 13710263Satgutier@umich.edu * @param lat The access latency. 13810263Satgutier@umich.edu * @return Pointer to the cache block if found. 13910263Satgutier@umich.edu */ 14011870Snikos.nikoleris@arm.com CacheBlk* accessBlock(Addr addr, bool is_secure, Cycles &lat) override 14110263Satgutier@umich.edu { 14212555Sodanrc@yahoo.com.br BlkType *blk = findBlock(addr, is_secure); 14310263Satgutier@umich.edu 14410263Satgutier@umich.edu // Access all tags in parallel, hence one in each way. The data side 14510263Satgutier@umich.edu // either accesses all blocks in parallel, or one block sequentially on 14610263Satgutier@umich.edu // a hit. Sequential access with a miss doesn't access data. 14710941Sdavid.guillen@arm.com tagAccesses += allocAssoc; 14810263Satgutier@umich.edu if (sequentialAccess) { 14911484Snikos.nikoleris@arm.com if (blk != nullptr) { 15010263Satgutier@umich.edu dataAccesses += 1; 15110263Satgutier@umich.edu } 15210263Satgutier@umich.edu } else { 15310941Sdavid.guillen@arm.com dataAccesses += allocAssoc; 15410263Satgutier@umich.edu } 15510263Satgutier@umich.edu 15611484Snikos.nikoleris@arm.com if (blk != nullptr) { 15711722Ssophiane.senni@gmail.com // If a cache hit 15811722Ssophiane.senni@gmail.com lat = accessLatency; 15911722Ssophiane.senni@gmail.com // Check if the block to be accessed is available. If not, 16011722Ssophiane.senni@gmail.com // apply the accessLatency on top of block->whenReady. 16111722Ssophiane.senni@gmail.com if (blk->whenReady > curTick() && 16211722Ssophiane.senni@gmail.com cache->ticksToCycles(blk->whenReady - curTick()) > 16311722Ssophiane.senni@gmail.com accessLatency) { 16411722Ssophiane.senni@gmail.com lat = cache->ticksToCycles(blk->whenReady - curTick()) + 16511722Ssophiane.senni@gmail.com accessLatency; 16610263Satgutier@umich.edu } 16712600Sodanrc@yahoo.com.br 16812600Sodanrc@yahoo.com.br // Update replacement data of accessed block 16912600Sodanrc@yahoo.com.br replacementPolicy->touch(blk); 17011722Ssophiane.senni@gmail.com } else { 17111722Ssophiane.senni@gmail.com // If a cache miss 17211722Ssophiane.senni@gmail.com lat = lookupLatency; 17310263Satgutier@umich.edu } 17410263Satgutier@umich.edu 17510263Satgutier@umich.edu return blk; 17610263Satgutier@umich.edu } 17710263Satgutier@umich.edu 17810263Satgutier@umich.edu /** 17910263Satgutier@umich.edu * Finds the given address in the cache, do not update replacement data. 18010263Satgutier@umich.edu * i.e. This is a no-side-effect find of a block. 18110263Satgutier@umich.edu * @param addr The address to find. 18210263Satgutier@umich.edu * @param is_secure True if the target memory space is secure. 18310263Satgutier@umich.edu * @param asid The address space ID. 18410263Satgutier@umich.edu * @return Pointer to the cache block if found. 18510263Satgutier@umich.edu */ 18611169Sandreas.hansson@arm.com CacheBlk* findBlock(Addr addr, bool is_secure) const override; 18710263Satgutier@umich.edu 18810263Satgutier@umich.edu /** 18912600Sodanrc@yahoo.com.br * Find replacement victim based on address. 19012600Sodanrc@yahoo.com.br * 19112600Sodanrc@yahoo.com.br * @param addr Address to find a victim for. 19212600Sodanrc@yahoo.com.br * @return Cache block to be replaced. 19310263Satgutier@umich.edu */ 19411169Sandreas.hansson@arm.com CacheBlk* findVictim(Addr addr) override 19510263Satgutier@umich.edu { 19612600Sodanrc@yahoo.com.br // Choose replacement victim from replacement candidates 19712600Sodanrc@yahoo.com.br return replacementPolicy->getVictim(getPossibleLocations(addr)); 19812600Sodanrc@yahoo.com.br } 19910263Satgutier@umich.edu 20012600Sodanrc@yahoo.com.br /** 20112600Sodanrc@yahoo.com.br * Find all possible block locations for insertion and replacement of 20212600Sodanrc@yahoo.com.br * an address. Should be called immediately before ReplacementPolicy's 20312600Sodanrc@yahoo.com.br * findVictim() not to break cache resizing. 20412600Sodanrc@yahoo.com.br * Returns blocks in all ways belonging to the set of the address. 20512600Sodanrc@yahoo.com.br * 20612600Sodanrc@yahoo.com.br * @param addr The addr to a find possible locations for. 20712600Sodanrc@yahoo.com.br * @return The possible locations. 20812600Sodanrc@yahoo.com.br */ 20912600Sodanrc@yahoo.com.br const std::vector<CacheBlk*> getPossibleLocations(Addr addr) 21012600Sodanrc@yahoo.com.br { 21112600Sodanrc@yahoo.com.br return sets[extractSet(addr)].blks; 21210263Satgutier@umich.edu } 21310263Satgutier@umich.edu 21410263Satgutier@umich.edu /** 21512636Sodanrc@yahoo.com.br * Insert the new block into the cache and update replacement data. 21612636Sodanrc@yahoo.com.br * 21710263Satgutier@umich.edu * @param pkt Packet holding the address to update 21810263Satgutier@umich.edu * @param blk The block to update. 21910263Satgutier@umich.edu */ 22012636Sodanrc@yahoo.com.br void insertBlock(PacketPtr pkt, CacheBlk *blk) override 22112636Sodanrc@yahoo.com.br { 22212636Sodanrc@yahoo.com.br // Insert block 22312636Sodanrc@yahoo.com.br BaseTags::insertBlock(pkt, blk); 22410274Smitch.hayenga@arm.com 22512636Sodanrc@yahoo.com.br // Update replacement policy 22612636Sodanrc@yahoo.com.br replacementPolicy->reset(blk); 22712636Sodanrc@yahoo.com.br } 22810263Satgutier@umich.edu 22910263Satgutier@umich.edu /** 23010941Sdavid.guillen@arm.com * Limit the allocation for the cache ways. 23110941Sdavid.guillen@arm.com * @param ways The maximum number of ways available for replacement. 23210941Sdavid.guillen@arm.com */ 23311169Sandreas.hansson@arm.com virtual void setWayAllocationMax(int ways) override 23410941Sdavid.guillen@arm.com { 23510941Sdavid.guillen@arm.com fatal_if(ways < 1, "Allocation limit must be greater than zero"); 23610941Sdavid.guillen@arm.com allocAssoc = ways; 23710941Sdavid.guillen@arm.com } 23810941Sdavid.guillen@arm.com 23910941Sdavid.guillen@arm.com /** 24010941Sdavid.guillen@arm.com * Get the way allocation mask limit. 24110941Sdavid.guillen@arm.com * @return The maximum number of ways available for replacement. 24210941Sdavid.guillen@arm.com */ 24311169Sandreas.hansson@arm.com virtual int getWayAllocationMax() const override 24410941Sdavid.guillen@arm.com { 24510941Sdavid.guillen@arm.com return allocAssoc; 24610941Sdavid.guillen@arm.com } 24710941Sdavid.guillen@arm.com 24810941Sdavid.guillen@arm.com /** 24910263Satgutier@umich.edu * Generate the tag from the given address. 25010263Satgutier@umich.edu * @param addr The address to get the tag from. 25110263Satgutier@umich.edu * @return The tag of the address. 25210263Satgutier@umich.edu */ 25311169Sandreas.hansson@arm.com Addr extractTag(Addr addr) const override 25410263Satgutier@umich.edu { 25510263Satgutier@umich.edu return (addr >> tagShift); 25610263Satgutier@umich.edu } 25710263Satgutier@umich.edu 25810263Satgutier@umich.edu /** 25910263Satgutier@umich.edu * Calculate the set index from the address. 26010263Satgutier@umich.edu * @param addr The address to get the set from. 26110263Satgutier@umich.edu * @return The set index of the address. 26210263Satgutier@umich.edu */ 26311169Sandreas.hansson@arm.com int extractSet(Addr addr) const override 26410263Satgutier@umich.edu { 26510263Satgutier@umich.edu return ((addr >> setShift) & setMask); 26610263Satgutier@umich.edu } 26710263Satgutier@umich.edu 26810263Satgutier@umich.edu /** 26912574Sodanrc@yahoo.com.br * Regenerate the block address from the tag and set. 27012574Sodanrc@yahoo.com.br * 27112574Sodanrc@yahoo.com.br * @param block The block. 27212574Sodanrc@yahoo.com.br * @return the block address. 27310263Satgutier@umich.edu */ 27412574Sodanrc@yahoo.com.br Addr regenerateBlkAddr(const CacheBlk* blk) const override 27510263Satgutier@umich.edu { 27612574Sodanrc@yahoo.com.br return ((blk->tag << tagShift) | ((Addr)blk->set << setShift)); 27710263Satgutier@umich.edu } 27810263Satgutier@umich.edu 27910263Satgutier@umich.edu /** 28010263Satgutier@umich.edu * Called at end of simulation to complete average block reference stats. 28110263Satgutier@umich.edu */ 28211169Sandreas.hansson@arm.com void cleanupRefs() override; 28310263Satgutier@umich.edu 28410263Satgutier@umich.edu /** 28510263Satgutier@umich.edu * Print all tags used 28610263Satgutier@umich.edu */ 28711169Sandreas.hansson@arm.com std::string print() const override; 28810263Satgutier@umich.edu 28910263Satgutier@umich.edu /** 29010263Satgutier@umich.edu * Called prior to dumping stats to compute task occupancy 29110263Satgutier@umich.edu */ 29211169Sandreas.hansson@arm.com void computeStats() override; 29310263Satgutier@umich.edu 29410263Satgutier@umich.edu /** 29510263Satgutier@umich.edu * Visit each block in the tag store and apply a visitor to the 29610263Satgutier@umich.edu * block. 29710263Satgutier@umich.edu * 29810263Satgutier@umich.edu * The visitor should be a function (or object that behaves like a 29910263Satgutier@umich.edu * function) that takes a cache block reference as its parameter 30010263Satgutier@umich.edu * and returns a bool. A visitor can request the traversal to be 30110263Satgutier@umich.edu * stopped by returning false, returning true causes it to be 30210263Satgutier@umich.edu * called for the next block in the tag store. 30310263Satgutier@umich.edu * 30410263Satgutier@umich.edu * \param visitor Visitor to call on each block. 30510263Satgutier@umich.edu */ 30611168Sandreas.hansson@arm.com void forEachBlk(CacheBlkVisitor &visitor) override { 30712679Sodanrc@yahoo.com.br for (CacheBlk& blk : blks) { 30812679Sodanrc@yahoo.com.br if (!visitor(blk)) 30910263Satgutier@umich.edu return; 31010263Satgutier@umich.edu } 31110263Satgutier@umich.edu } 31210263Satgutier@umich.edu}; 31310263Satgutier@umich.edu 31412492Sodanrc@yahoo.com.br#endif //__MEM_CACHE_TAGS_BASE_SET_ASSOC_HH__ 315