base_set_assoc.hh revision 12744
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" 5712684Sodanrc@yahoo.com.br#include "debug/CacheRepl.hh" 5811486Snikos.nikoleris@arm.com#include "mem/cache/base.hh" 5911486Snikos.nikoleris@arm.com#include "mem/cache/blk.hh" 6012684Sodanrc@yahoo.com.br#include "mem/cache/replacement_policies/base.hh" 6110263Satgutier@umich.edu#include "mem/cache/tags/base.hh" 6210263Satgutier@umich.edu#include "mem/cache/tags/cacheset.hh" 6310263Satgutier@umich.edu#include "mem/packet.hh" 6410263Satgutier@umich.edu#include "params/BaseSetAssoc.hh" 6510263Satgutier@umich.edu 6610263Satgutier@umich.edu/** 6710263Satgutier@umich.edu * A BaseSetAssoc 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 7112600Sodanrc@yahoo.com.br * cache lines (ways). A cache line is mapped onto a set, and can be placed 7212600Sodanrc@yahoo.com.br * into any of the ways of this set. 7310263Satgutier@umich.edu */ 7410263Satgutier@umich.educlass BaseSetAssoc : public BaseTags 7510263Satgutier@umich.edu{ 7610263Satgutier@umich.edu public: 7710263Satgutier@umich.edu /** Typedef the block type used in this tag store. */ 7810263Satgutier@umich.edu typedef CacheBlk BlkType; 7910263Satgutier@umich.edu /** Typedef the set type used in this tag store. */ 8010263Satgutier@umich.edu typedef CacheSet<CacheBlk> SetType; 8110263Satgutier@umich.edu 8210263Satgutier@umich.edu protected: 8310263Satgutier@umich.edu /** The associativity of the cache. */ 8410263Satgutier@umich.edu const unsigned assoc; 8510941Sdavid.guillen@arm.com /** The allocatable associativity of the cache (alloc mask). */ 8610941Sdavid.guillen@arm.com unsigned allocAssoc; 8712548Sodanrc@yahoo.com.br 8812548Sodanrc@yahoo.com.br /** The cache blocks. */ 8912548Sodanrc@yahoo.com.br std::vector<BlkType> blks; 9012548Sodanrc@yahoo.com.br 9110263Satgutier@umich.edu /** The number of sets in the cache. */ 9210263Satgutier@umich.edu const unsigned numSets; 9312548Sodanrc@yahoo.com.br 9410263Satgutier@umich.edu /** Whether tags and data are accessed sequentially. */ 9510263Satgutier@umich.edu const bool sequentialAccess; 9610263Satgutier@umich.edu 9710263Satgutier@umich.edu /** The cache sets. */ 9812548Sodanrc@yahoo.com.br std::vector<SetType> sets; 9910263Satgutier@umich.edu 10010263Satgutier@umich.edu /** The amount to shift the address to get the set. */ 10110263Satgutier@umich.edu int setShift; 10210263Satgutier@umich.edu /** The amount to shift the address to get the tag. */ 10310263Satgutier@umich.edu int tagShift; 10410263Satgutier@umich.edu /** Mask out all bits that aren't part of the set index. */ 10510263Satgutier@umich.edu unsigned setMask; 10610263Satgutier@umich.edu 10712600Sodanrc@yahoo.com.br /** Replacement policy */ 10812600Sodanrc@yahoo.com.br BaseReplacementPolicy *replacementPolicy; 10912600Sodanrc@yahoo.com.br 11012600Sodanrc@yahoo.com.br public: 11110263Satgutier@umich.edu /** Convenience typedef. */ 11210263Satgutier@umich.edu typedef BaseSetAssocParams Params; 11310263Satgutier@umich.edu 11410263Satgutier@umich.edu /** 11510263Satgutier@umich.edu * Construct and initialize this tag store. 11610263Satgutier@umich.edu */ 11710263Satgutier@umich.edu BaseSetAssoc(const Params *p); 11810263Satgutier@umich.edu 11910263Satgutier@umich.edu /** 12010263Satgutier@umich.edu * Destructor 12110263Satgutier@umich.edu */ 12212548Sodanrc@yahoo.com.br virtual ~BaseSetAssoc() {}; 12310263Satgutier@umich.edu 12410263Satgutier@umich.edu /** 12512684Sodanrc@yahoo.com.br * This function updates the tags when a block is invalidated but does 12612684Sodanrc@yahoo.com.br * not invalidate the block itself. It also updates the replacement data. 12712684Sodanrc@yahoo.com.br * 12812684Sodanrc@yahoo.com.br * @param blk The block to invalidate. 12912684Sodanrc@yahoo.com.br */ 13012684Sodanrc@yahoo.com.br void invalidate(CacheBlk *blk) override; 13112684Sodanrc@yahoo.com.br 13212684Sodanrc@yahoo.com.br /** 13310263Satgutier@umich.edu * Access block and update replacement data. May not succeed, in which case 13411484Snikos.nikoleris@arm.com * nullptr is returned. This has all the implications of a cache 13510263Satgutier@umich.edu * access and should only be used as such. Returns the access latency as a 13610263Satgutier@umich.edu * side effect. 13710263Satgutier@umich.edu * @param addr The address to find. 13810263Satgutier@umich.edu * @param is_secure True if the target memory space is secure. 13910263Satgutier@umich.edu * @param lat The access latency. 14010263Satgutier@umich.edu * @return Pointer to the cache block if found. 14110263Satgutier@umich.edu */ 14211870Snikos.nikoleris@arm.com CacheBlk* accessBlock(Addr addr, bool is_secure, Cycles &lat) override 14310263Satgutier@umich.edu { 14412555Sodanrc@yahoo.com.br BlkType *blk = findBlock(addr, is_secure); 14510263Satgutier@umich.edu 14610263Satgutier@umich.edu // Access all tags in parallel, hence one in each way. The data side 14710263Satgutier@umich.edu // either accesses all blocks in parallel, or one block sequentially on 14810263Satgutier@umich.edu // a hit. Sequential access with a miss doesn't access data. 14910941Sdavid.guillen@arm.com tagAccesses += allocAssoc; 15010263Satgutier@umich.edu if (sequentialAccess) { 15111484Snikos.nikoleris@arm.com if (blk != nullptr) { 15210263Satgutier@umich.edu dataAccesses += 1; 15310263Satgutier@umich.edu } 15410263Satgutier@umich.edu } else { 15510941Sdavid.guillen@arm.com dataAccesses += allocAssoc; 15610263Satgutier@umich.edu } 15710263Satgutier@umich.edu 15811484Snikos.nikoleris@arm.com if (blk != nullptr) { 15911722Ssophiane.senni@gmail.com // If a cache hit 16011722Ssophiane.senni@gmail.com lat = accessLatency; 16111722Ssophiane.senni@gmail.com // Check if the block to be accessed is available. If not, 16211722Ssophiane.senni@gmail.com // apply the accessLatency on top of block->whenReady. 16311722Ssophiane.senni@gmail.com if (blk->whenReady > curTick() && 16411722Ssophiane.senni@gmail.com cache->ticksToCycles(blk->whenReady - curTick()) > 16511722Ssophiane.senni@gmail.com accessLatency) { 16611722Ssophiane.senni@gmail.com lat = cache->ticksToCycles(blk->whenReady - curTick()) + 16711722Ssophiane.senni@gmail.com accessLatency; 16810263Satgutier@umich.edu } 16912600Sodanrc@yahoo.com.br 17012684Sodanrc@yahoo.com.br // Update number of references to accessed block 17112684Sodanrc@yahoo.com.br blk->refCount++; 17212684Sodanrc@yahoo.com.br 17312600Sodanrc@yahoo.com.br // Update replacement data of accessed block 17412684Sodanrc@yahoo.com.br replacementPolicy->touch(blk->replacementData); 17511722Ssophiane.senni@gmail.com } else { 17611722Ssophiane.senni@gmail.com // If a cache miss 17711722Ssophiane.senni@gmail.com lat = lookupLatency; 17810263Satgutier@umich.edu } 17910263Satgutier@umich.edu 18010263Satgutier@umich.edu return blk; 18110263Satgutier@umich.edu } 18210263Satgutier@umich.edu 18310263Satgutier@umich.edu /** 18410263Satgutier@umich.edu * Finds the given address in the cache, do not update replacement data. 18510263Satgutier@umich.edu * i.e. This is a no-side-effect find of a block. 18610263Satgutier@umich.edu * @param addr The address to find. 18710263Satgutier@umich.edu * @param is_secure True if the target memory space is secure. 18810263Satgutier@umich.edu * @param asid The address space ID. 18910263Satgutier@umich.edu * @return Pointer to the cache block if found. 19010263Satgutier@umich.edu */ 19111169Sandreas.hansson@arm.com CacheBlk* findBlock(Addr addr, bool is_secure) const override; 19210263Satgutier@umich.edu 19310263Satgutier@umich.edu /** 19412743Sodanrc@yahoo.com.br * Find a block given set and way. 19512743Sodanrc@yahoo.com.br * 19612743Sodanrc@yahoo.com.br * @param set The set of the block. 19712743Sodanrc@yahoo.com.br * @param way The way of the block. 19812743Sodanrc@yahoo.com.br * @return The block. 19912743Sodanrc@yahoo.com.br */ 20012743Sodanrc@yahoo.com.br ReplaceableEntry* findBlockBySetAndWay(int set, int way) const override; 20112743Sodanrc@yahoo.com.br 20212743Sodanrc@yahoo.com.br /** 20312744Sodanrc@yahoo.com.br * Find replacement victim based on address. The list of evicted blocks 20412744Sodanrc@yahoo.com.br * only contains the victim. 20512600Sodanrc@yahoo.com.br * 20612600Sodanrc@yahoo.com.br * @param addr Address to find a victim for. 20712744Sodanrc@yahoo.com.br * @param evict_blks Cache blocks to be evicted. 20812600Sodanrc@yahoo.com.br * @return Cache block to be replaced. 20910263Satgutier@umich.edu */ 21012744Sodanrc@yahoo.com.br CacheBlk* findVictim(Addr addr, std::vector<CacheBlk*>& evict_blks) const 21112744Sodanrc@yahoo.com.br override 21210263Satgutier@umich.edu { 21312684Sodanrc@yahoo.com.br // Get possible locations for the victim block 21412684Sodanrc@yahoo.com.br std::vector<CacheBlk*> locations = getPossibleLocations(addr); 21512684Sodanrc@yahoo.com.br 21612600Sodanrc@yahoo.com.br // Choose replacement victim from replacement candidates 21712684Sodanrc@yahoo.com.br CacheBlk* victim = static_cast<CacheBlk*>(replacementPolicy->getVictim( 21812684Sodanrc@yahoo.com.br std::vector<ReplaceableEntry*>( 21912684Sodanrc@yahoo.com.br locations.begin(), locations.end()))); 22012684Sodanrc@yahoo.com.br 22112744Sodanrc@yahoo.com.br // There is only one eviction for this replacement 22212744Sodanrc@yahoo.com.br evict_blks.push_back(victim); 22312744Sodanrc@yahoo.com.br 22412684Sodanrc@yahoo.com.br DPRINTF(CacheRepl, "set %x, way %x: selecting blk for replacement\n", 22512684Sodanrc@yahoo.com.br victim->set, victim->way); 22612684Sodanrc@yahoo.com.br 22712684Sodanrc@yahoo.com.br return victim; 22812600Sodanrc@yahoo.com.br } 22910263Satgutier@umich.edu 23012600Sodanrc@yahoo.com.br /** 23112600Sodanrc@yahoo.com.br * Find all possible block locations for insertion and replacement of 23212600Sodanrc@yahoo.com.br * an address. Should be called immediately before ReplacementPolicy's 23312600Sodanrc@yahoo.com.br * findVictim() not to break cache resizing. 23412600Sodanrc@yahoo.com.br * Returns blocks in all ways belonging to the set of the address. 23512600Sodanrc@yahoo.com.br * 23612600Sodanrc@yahoo.com.br * @param addr The addr to a find possible locations for. 23712600Sodanrc@yahoo.com.br * @return The possible locations. 23812600Sodanrc@yahoo.com.br */ 23912744Sodanrc@yahoo.com.br const std::vector<CacheBlk*> getPossibleLocations(Addr addr) const 24012600Sodanrc@yahoo.com.br { 24112600Sodanrc@yahoo.com.br return sets[extractSet(addr)].blks; 24210263Satgutier@umich.edu } 24310263Satgutier@umich.edu 24410263Satgutier@umich.edu /** 24512636Sodanrc@yahoo.com.br * Insert the new block into the cache and update replacement data. 24612636Sodanrc@yahoo.com.br * 24710263Satgutier@umich.edu * @param pkt Packet holding the address to update 24810263Satgutier@umich.edu * @param blk The block to update. 24910263Satgutier@umich.edu */ 25012636Sodanrc@yahoo.com.br void insertBlock(PacketPtr pkt, CacheBlk *blk) override 25112636Sodanrc@yahoo.com.br { 25212636Sodanrc@yahoo.com.br // Insert block 25312636Sodanrc@yahoo.com.br BaseTags::insertBlock(pkt, blk); 25410274Smitch.hayenga@arm.com 25512636Sodanrc@yahoo.com.br // Update replacement policy 25612684Sodanrc@yahoo.com.br replacementPolicy->reset(blk->replacementData); 25712636Sodanrc@yahoo.com.br } 25810263Satgutier@umich.edu 25910263Satgutier@umich.edu /** 26010941Sdavid.guillen@arm.com * Limit the allocation for the cache ways. 26110941Sdavid.guillen@arm.com * @param ways The maximum number of ways available for replacement. 26210941Sdavid.guillen@arm.com */ 26311169Sandreas.hansson@arm.com virtual void setWayAllocationMax(int ways) override 26410941Sdavid.guillen@arm.com { 26510941Sdavid.guillen@arm.com fatal_if(ways < 1, "Allocation limit must be greater than zero"); 26610941Sdavid.guillen@arm.com allocAssoc = ways; 26710941Sdavid.guillen@arm.com } 26810941Sdavid.guillen@arm.com 26910941Sdavid.guillen@arm.com /** 27010941Sdavid.guillen@arm.com * Get the way allocation mask limit. 27110941Sdavid.guillen@arm.com * @return The maximum number of ways available for replacement. 27210941Sdavid.guillen@arm.com */ 27311169Sandreas.hansson@arm.com virtual int getWayAllocationMax() const override 27410941Sdavid.guillen@arm.com { 27510941Sdavid.guillen@arm.com return allocAssoc; 27610941Sdavid.guillen@arm.com } 27710941Sdavid.guillen@arm.com 27810941Sdavid.guillen@arm.com /** 27910263Satgutier@umich.edu * Generate the tag from the given address. 28010263Satgutier@umich.edu * @param addr The address to get the tag from. 28110263Satgutier@umich.edu * @return The tag of the address. 28210263Satgutier@umich.edu */ 28311169Sandreas.hansson@arm.com Addr extractTag(Addr addr) const override 28410263Satgutier@umich.edu { 28510263Satgutier@umich.edu return (addr >> tagShift); 28610263Satgutier@umich.edu } 28710263Satgutier@umich.edu 28810263Satgutier@umich.edu /** 28912574Sodanrc@yahoo.com.br * Regenerate the block address from the tag and set. 29012574Sodanrc@yahoo.com.br * 29112574Sodanrc@yahoo.com.br * @param block The block. 29212574Sodanrc@yahoo.com.br * @return the block address. 29310263Satgutier@umich.edu */ 29412574Sodanrc@yahoo.com.br Addr regenerateBlkAddr(const CacheBlk* blk) const override 29510263Satgutier@umich.edu { 29612574Sodanrc@yahoo.com.br return ((blk->tag << tagShift) | ((Addr)blk->set << setShift)); 29710263Satgutier@umich.edu } 29810263Satgutier@umich.edu 29912728Snikos.nikoleris@arm.com void forEachBlk(std::function<void(CacheBlk &)> visitor) override { 30012728Snikos.nikoleris@arm.com for (CacheBlk& blk : blks) { 30112728Snikos.nikoleris@arm.com visitor(blk); 30212728Snikos.nikoleris@arm.com } 30312728Snikos.nikoleris@arm.com } 30410263Satgutier@umich.edu 30512728Snikos.nikoleris@arm.com bool anyBlk(std::function<bool(CacheBlk &)> visitor) override { 30612679Sodanrc@yahoo.com.br for (CacheBlk& blk : blks) { 30712728Snikos.nikoleris@arm.com if (visitor(blk)) { 30812728Snikos.nikoleris@arm.com return true; 30912728Snikos.nikoleris@arm.com } 31010263Satgutier@umich.edu } 31112728Snikos.nikoleris@arm.com return false; 31210263Satgutier@umich.edu } 31312731Sodanrc@yahoo.com.br 31412731Sodanrc@yahoo.com.br private: 31512731Sodanrc@yahoo.com.br /** 31612731Sodanrc@yahoo.com.br * Calculate the set index from the address. 31712731Sodanrc@yahoo.com.br * 31812731Sodanrc@yahoo.com.br * @param addr The address to get the set from. 31912731Sodanrc@yahoo.com.br * @return The set index of the address. 32012731Sodanrc@yahoo.com.br */ 32112731Sodanrc@yahoo.com.br int extractSet(Addr addr) const 32212731Sodanrc@yahoo.com.br { 32312731Sodanrc@yahoo.com.br return ((addr >> setShift) & setMask); 32412731Sodanrc@yahoo.com.br } 32510263Satgutier@umich.edu}; 32610263Satgutier@umich.edu 32712492Sodanrc@yahoo.com.br#endif //__MEM_CACHE_TAGS_BASE_SET_ASSOC_HH__ 328