base_set_assoc.hh revision 12684
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 <vector> 5410263Satgutier@umich.edu 5512684Sodanrc@yahoo.com.br#include "debug/CacheRepl.hh" 5611486Snikos.nikoleris@arm.com#include "mem/cache/base.hh" 5711486Snikos.nikoleris@arm.com#include "mem/cache/blk.hh" 5812684Sodanrc@yahoo.com.br#include "mem/cache/replacement_policies/base.hh" 5910263Satgutier@umich.edu#include "mem/cache/tags/base.hh" 6010263Satgutier@umich.edu#include "mem/cache/tags/cacheset.hh" 6110263Satgutier@umich.edu#include "mem/packet.hh" 6210263Satgutier@umich.edu#include "params/BaseSetAssoc.hh" 6310263Satgutier@umich.edu 6410263Satgutier@umich.edu/** 6510263Satgutier@umich.edu * A BaseSetAssoc cache tag store. 6610263Satgutier@umich.edu * @sa \ref gem5MemorySystem "gem5 Memory System" 6710263Satgutier@umich.edu * 6812600Sodanrc@yahoo.com.br * The BaseSetAssoc placement policy divides the cache into s sets of w 6912600Sodanrc@yahoo.com.br * cache lines (ways). A cache line is mapped onto a set, and can be placed 7012600Sodanrc@yahoo.com.br * into any of the ways of this set. 7110263Satgutier@umich.edu */ 7210263Satgutier@umich.educlass BaseSetAssoc : public BaseTags 7310263Satgutier@umich.edu{ 7410263Satgutier@umich.edu public: 7510263Satgutier@umich.edu /** Typedef the block type used in this tag store. */ 7610263Satgutier@umich.edu typedef CacheBlk BlkType; 7710263Satgutier@umich.edu /** Typedef the set type used in this tag store. */ 7810263Satgutier@umich.edu typedef CacheSet<CacheBlk> SetType; 7910263Satgutier@umich.edu 8010263Satgutier@umich.edu protected: 8110263Satgutier@umich.edu /** The associativity of the cache. */ 8210263Satgutier@umich.edu const unsigned assoc; 8310941Sdavid.guillen@arm.com /** The allocatable associativity of the cache (alloc mask). */ 8410941Sdavid.guillen@arm.com unsigned allocAssoc; 8512548Sodanrc@yahoo.com.br 8612548Sodanrc@yahoo.com.br /** The cache blocks. */ 8712548Sodanrc@yahoo.com.br std::vector<BlkType> blks; 8812548Sodanrc@yahoo.com.br 8910263Satgutier@umich.edu /** The number of sets in the cache. */ 9010263Satgutier@umich.edu const unsigned numSets; 9112548Sodanrc@yahoo.com.br 9210263Satgutier@umich.edu /** Whether tags and data are accessed sequentially. */ 9310263Satgutier@umich.edu const bool sequentialAccess; 9410263Satgutier@umich.edu 9510263Satgutier@umich.edu /** The cache sets. */ 9612548Sodanrc@yahoo.com.br std::vector<SetType> sets; 9710263Satgutier@umich.edu 9810263Satgutier@umich.edu /** The amount to shift the address to get the set. */ 9910263Satgutier@umich.edu int setShift; 10010263Satgutier@umich.edu /** The amount to shift the address to get the tag. */ 10110263Satgutier@umich.edu int tagShift; 10210263Satgutier@umich.edu /** Mask out all bits that aren't part of the set index. */ 10310263Satgutier@umich.edu unsigned setMask; 10410263Satgutier@umich.edu 10512600Sodanrc@yahoo.com.br /** Replacement policy */ 10612600Sodanrc@yahoo.com.br BaseReplacementPolicy *replacementPolicy; 10712600Sodanrc@yahoo.com.br 10812600Sodanrc@yahoo.com.br public: 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 /** 12312684Sodanrc@yahoo.com.br * This function updates the tags when a block is invalidated but does 12412684Sodanrc@yahoo.com.br * not invalidate the block itself. It also updates the replacement data. 12512684Sodanrc@yahoo.com.br * 12612684Sodanrc@yahoo.com.br * @param blk The block to invalidate. 12712684Sodanrc@yahoo.com.br */ 12812684Sodanrc@yahoo.com.br void invalidate(CacheBlk *blk) override; 12912684Sodanrc@yahoo.com.br 13012684Sodanrc@yahoo.com.br /** 13110941Sdavid.guillen@arm.com * Find the cache block given set and way 13210941Sdavid.guillen@arm.com * @param set The set of the block. 13310941Sdavid.guillen@arm.com * @param way The way of the block. 13410941Sdavid.guillen@arm.com * @return The cache block. 13510941Sdavid.guillen@arm.com */ 13611169Sandreas.hansson@arm.com CacheBlk *findBlockBySetAndWay(int set, int way) const override; 13710941Sdavid.guillen@arm.com 13810941Sdavid.guillen@arm.com /** 13910263Satgutier@umich.edu * Access block and update replacement data. May not succeed, in which case 14011484Snikos.nikoleris@arm.com * nullptr is returned. This has all the implications of a cache 14110263Satgutier@umich.edu * access and should only be used as such. Returns the access latency as a 14210263Satgutier@umich.edu * side effect. 14310263Satgutier@umich.edu * @param addr The address to find. 14410263Satgutier@umich.edu * @param is_secure True if the target memory space is secure. 14510263Satgutier@umich.edu * @param lat The access latency. 14610263Satgutier@umich.edu * @return Pointer to the cache block if found. 14710263Satgutier@umich.edu */ 14811870Snikos.nikoleris@arm.com CacheBlk* accessBlock(Addr addr, bool is_secure, Cycles &lat) override 14910263Satgutier@umich.edu { 15012555Sodanrc@yahoo.com.br BlkType *blk = findBlock(addr, is_secure); 15110263Satgutier@umich.edu 15210263Satgutier@umich.edu // Access all tags in parallel, hence one in each way. The data side 15310263Satgutier@umich.edu // either accesses all blocks in parallel, or one block sequentially on 15410263Satgutier@umich.edu // a hit. Sequential access with a miss doesn't access data. 15510941Sdavid.guillen@arm.com tagAccesses += allocAssoc; 15610263Satgutier@umich.edu if (sequentialAccess) { 15711484Snikos.nikoleris@arm.com if (blk != nullptr) { 15810263Satgutier@umich.edu dataAccesses += 1; 15910263Satgutier@umich.edu } 16010263Satgutier@umich.edu } else { 16110941Sdavid.guillen@arm.com dataAccesses += allocAssoc; 16210263Satgutier@umich.edu } 16310263Satgutier@umich.edu 16411484Snikos.nikoleris@arm.com if (blk != nullptr) { 16511722Ssophiane.senni@gmail.com // If a cache hit 16611722Ssophiane.senni@gmail.com lat = accessLatency; 16711722Ssophiane.senni@gmail.com // Check if the block to be accessed is available. If not, 16811722Ssophiane.senni@gmail.com // apply the accessLatency on top of block->whenReady. 16911722Ssophiane.senni@gmail.com if (blk->whenReady > curTick() && 17011722Ssophiane.senni@gmail.com cache->ticksToCycles(blk->whenReady - curTick()) > 17111722Ssophiane.senni@gmail.com accessLatency) { 17211722Ssophiane.senni@gmail.com lat = cache->ticksToCycles(blk->whenReady - curTick()) + 17311722Ssophiane.senni@gmail.com accessLatency; 17410263Satgutier@umich.edu } 17512600Sodanrc@yahoo.com.br 17612684Sodanrc@yahoo.com.br // Update number of references to accessed block 17712684Sodanrc@yahoo.com.br blk->refCount++; 17812684Sodanrc@yahoo.com.br 17912600Sodanrc@yahoo.com.br // Update replacement data of accessed block 18012684Sodanrc@yahoo.com.br replacementPolicy->touch(blk->replacementData); 18111722Ssophiane.senni@gmail.com } else { 18211722Ssophiane.senni@gmail.com // If a cache miss 18311722Ssophiane.senni@gmail.com lat = lookupLatency; 18410263Satgutier@umich.edu } 18510263Satgutier@umich.edu 18610263Satgutier@umich.edu return blk; 18710263Satgutier@umich.edu } 18810263Satgutier@umich.edu 18910263Satgutier@umich.edu /** 19010263Satgutier@umich.edu * Finds the given address in the cache, do not update replacement data. 19110263Satgutier@umich.edu * i.e. This is a no-side-effect find of a block. 19210263Satgutier@umich.edu * @param addr The address to find. 19310263Satgutier@umich.edu * @param is_secure True if the target memory space is secure. 19410263Satgutier@umich.edu * @param asid The address space ID. 19510263Satgutier@umich.edu * @return Pointer to the cache block if found. 19610263Satgutier@umich.edu */ 19711169Sandreas.hansson@arm.com CacheBlk* findBlock(Addr addr, bool is_secure) const override; 19810263Satgutier@umich.edu 19910263Satgutier@umich.edu /** 20012600Sodanrc@yahoo.com.br * Find replacement victim based on address. 20112600Sodanrc@yahoo.com.br * 20212600Sodanrc@yahoo.com.br * @param addr Address to find a victim for. 20312600Sodanrc@yahoo.com.br * @return Cache block to be replaced. 20410263Satgutier@umich.edu */ 20511169Sandreas.hansson@arm.com CacheBlk* findVictim(Addr addr) override 20610263Satgutier@umich.edu { 20712684Sodanrc@yahoo.com.br // Get possible locations for the victim block 20812684Sodanrc@yahoo.com.br std::vector<CacheBlk*> locations = getPossibleLocations(addr); 20912684Sodanrc@yahoo.com.br 21012600Sodanrc@yahoo.com.br // Choose replacement victim from replacement candidates 21112684Sodanrc@yahoo.com.br CacheBlk* victim = static_cast<CacheBlk*>(replacementPolicy->getVictim( 21212684Sodanrc@yahoo.com.br std::vector<ReplaceableEntry*>( 21312684Sodanrc@yahoo.com.br locations.begin(), locations.end()))); 21412684Sodanrc@yahoo.com.br 21512684Sodanrc@yahoo.com.br DPRINTF(CacheRepl, "set %x, way %x: selecting blk for replacement\n", 21612684Sodanrc@yahoo.com.br victim->set, victim->way); 21712684Sodanrc@yahoo.com.br 21812684Sodanrc@yahoo.com.br return victim; 21912600Sodanrc@yahoo.com.br } 22010263Satgutier@umich.edu 22112600Sodanrc@yahoo.com.br /** 22212600Sodanrc@yahoo.com.br * Find all possible block locations for insertion and replacement of 22312600Sodanrc@yahoo.com.br * an address. Should be called immediately before ReplacementPolicy's 22412600Sodanrc@yahoo.com.br * findVictim() not to break cache resizing. 22512600Sodanrc@yahoo.com.br * Returns blocks in all ways belonging to the set of the address. 22612600Sodanrc@yahoo.com.br * 22712600Sodanrc@yahoo.com.br * @param addr The addr to a find possible locations for. 22812600Sodanrc@yahoo.com.br * @return The possible locations. 22912600Sodanrc@yahoo.com.br */ 23012600Sodanrc@yahoo.com.br const std::vector<CacheBlk*> getPossibleLocations(Addr addr) 23112600Sodanrc@yahoo.com.br { 23212600Sodanrc@yahoo.com.br return sets[extractSet(addr)].blks; 23310263Satgutier@umich.edu } 23410263Satgutier@umich.edu 23510263Satgutier@umich.edu /** 23612636Sodanrc@yahoo.com.br * Insert the new block into the cache and update replacement data. 23712636Sodanrc@yahoo.com.br * 23810263Satgutier@umich.edu * @param pkt Packet holding the address to update 23910263Satgutier@umich.edu * @param blk The block to update. 24010263Satgutier@umich.edu */ 24112636Sodanrc@yahoo.com.br void insertBlock(PacketPtr pkt, CacheBlk *blk) override 24212636Sodanrc@yahoo.com.br { 24312636Sodanrc@yahoo.com.br // Insert block 24412636Sodanrc@yahoo.com.br BaseTags::insertBlock(pkt, blk); 24510274Smitch.hayenga@arm.com 24612636Sodanrc@yahoo.com.br // Update replacement policy 24712684Sodanrc@yahoo.com.br replacementPolicy->reset(blk->replacementData); 24812636Sodanrc@yahoo.com.br } 24910263Satgutier@umich.edu 25010263Satgutier@umich.edu /** 25110941Sdavid.guillen@arm.com * Limit the allocation for the cache ways. 25210941Sdavid.guillen@arm.com * @param ways The maximum number of ways available for replacement. 25310941Sdavid.guillen@arm.com */ 25411169Sandreas.hansson@arm.com virtual void setWayAllocationMax(int ways) override 25510941Sdavid.guillen@arm.com { 25610941Sdavid.guillen@arm.com fatal_if(ways < 1, "Allocation limit must be greater than zero"); 25710941Sdavid.guillen@arm.com allocAssoc = ways; 25810941Sdavid.guillen@arm.com } 25910941Sdavid.guillen@arm.com 26010941Sdavid.guillen@arm.com /** 26110941Sdavid.guillen@arm.com * Get the way allocation mask limit. 26210941Sdavid.guillen@arm.com * @return The maximum number of ways available for replacement. 26310941Sdavid.guillen@arm.com */ 26411169Sandreas.hansson@arm.com virtual int getWayAllocationMax() const override 26510941Sdavid.guillen@arm.com { 26610941Sdavid.guillen@arm.com return allocAssoc; 26710941Sdavid.guillen@arm.com } 26810941Sdavid.guillen@arm.com 26910941Sdavid.guillen@arm.com /** 27010263Satgutier@umich.edu * Generate the tag from the given address. 27110263Satgutier@umich.edu * @param addr The address to get the tag from. 27210263Satgutier@umich.edu * @return The tag of the address. 27310263Satgutier@umich.edu */ 27411169Sandreas.hansson@arm.com Addr extractTag(Addr addr) const override 27510263Satgutier@umich.edu { 27610263Satgutier@umich.edu return (addr >> tagShift); 27710263Satgutier@umich.edu } 27810263Satgutier@umich.edu 27910263Satgutier@umich.edu /** 28010263Satgutier@umich.edu * Calculate the set index from the address. 28110263Satgutier@umich.edu * @param addr The address to get the set from. 28210263Satgutier@umich.edu * @return The set index of the address. 28310263Satgutier@umich.edu */ 28411169Sandreas.hansson@arm.com int extractSet(Addr addr) const override 28510263Satgutier@umich.edu { 28610263Satgutier@umich.edu return ((addr >> setShift) & setMask); 28710263Satgutier@umich.edu } 28810263Satgutier@umich.edu 28910263Satgutier@umich.edu /** 29012574Sodanrc@yahoo.com.br * Regenerate the block address from the tag and set. 29112574Sodanrc@yahoo.com.br * 29212574Sodanrc@yahoo.com.br * @param block The block. 29312574Sodanrc@yahoo.com.br * @return the block address. 29410263Satgutier@umich.edu */ 29512574Sodanrc@yahoo.com.br Addr regenerateBlkAddr(const CacheBlk* blk) const override 29610263Satgutier@umich.edu { 29712574Sodanrc@yahoo.com.br return ((blk->tag << tagShift) | ((Addr)blk->set << setShift)); 29810263Satgutier@umich.edu } 29910263Satgutier@umich.edu 30010263Satgutier@umich.edu /** 30110263Satgutier@umich.edu * Called at end of simulation to complete average block reference stats. 30210263Satgutier@umich.edu */ 30311169Sandreas.hansson@arm.com void cleanupRefs() override; 30410263Satgutier@umich.edu 30510263Satgutier@umich.edu /** 30610263Satgutier@umich.edu * Print all tags used 30710263Satgutier@umich.edu */ 30811169Sandreas.hansson@arm.com std::string print() const override; 30910263Satgutier@umich.edu 31010263Satgutier@umich.edu /** 31110263Satgutier@umich.edu * Called prior to dumping stats to compute task occupancy 31210263Satgutier@umich.edu */ 31311169Sandreas.hansson@arm.com void computeStats() override; 31410263Satgutier@umich.edu 31510263Satgutier@umich.edu /** 31610263Satgutier@umich.edu * Visit each block in the tag store and apply a visitor to the 31710263Satgutier@umich.edu * block. 31810263Satgutier@umich.edu * 31910263Satgutier@umich.edu * The visitor should be a function (or object that behaves like a 32010263Satgutier@umich.edu * function) that takes a cache block reference as its parameter 32110263Satgutier@umich.edu * and returns a bool. A visitor can request the traversal to be 32210263Satgutier@umich.edu * stopped by returning false, returning true causes it to be 32310263Satgutier@umich.edu * called for the next block in the tag store. 32410263Satgutier@umich.edu * 32510263Satgutier@umich.edu * \param visitor Visitor to call on each block. 32610263Satgutier@umich.edu */ 32711168Sandreas.hansson@arm.com void forEachBlk(CacheBlkVisitor &visitor) override { 32812679Sodanrc@yahoo.com.br for (CacheBlk& blk : blks) { 32912679Sodanrc@yahoo.com.br if (!visitor(blk)) 33010263Satgutier@umich.edu return; 33110263Satgutier@umich.edu } 33210263Satgutier@umich.edu } 33310263Satgutier@umich.edu}; 33410263Satgutier@umich.edu 33512492Sodanrc@yahoo.com.br#endif //__MEM_CACHE_TAGS_BASE_SET_ASSOC_HH__ 336