base_set_assoc.hh revision 10274
110263Satgutier@umich.edu/* 210263Satgutier@umich.edu * Copyright (c) 2012-2013 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 4810263Satgutier@umich.edu#ifndef __MEM_CACHE_TAGS_BASESETASSOC_HH__ 4910263Satgutier@umich.edu#define __MEM_CACHE_TAGS_BASESETASSOC_HH__ 5010263Satgutier@umich.edu 5110263Satgutier@umich.edu#include <cassert> 5210263Satgutier@umich.edu#include <cstring> 5310263Satgutier@umich.edu#include <list> 5410263Satgutier@umich.edu 5510263Satgutier@umich.edu#include "mem/cache/tags/base.hh" 5610263Satgutier@umich.edu#include "mem/cache/tags/cacheset.hh" 5710263Satgutier@umich.edu#include "mem/cache/base.hh" 5810263Satgutier@umich.edu#include "mem/cache/blk.hh" 5910263Satgutier@umich.edu#include "mem/packet.hh" 6010263Satgutier@umich.edu#include "params/BaseSetAssoc.hh" 6110263Satgutier@umich.edu 6210263Satgutier@umich.edu/** 6310263Satgutier@umich.edu * A BaseSetAssoc cache tag store. 6410263Satgutier@umich.edu * @sa \ref gem5MemorySystem "gem5 Memory System" 6510263Satgutier@umich.edu * 6610263Satgutier@umich.edu * The BaseSetAssoc tags provide a base, as well as the functionality 6710263Satgutier@umich.edu * common to any set associative tags. Any derived class must implement 6810263Satgutier@umich.edu * the methods related to the specifics of the actual replacment policy. 6910263Satgutier@umich.edu * These are: 7010263Satgutier@umich.edu * 7110263Satgutier@umich.edu * BlkType* accessBlock(); 7210263Satgutier@umich.edu * BlkType* findVictim(); 7310263Satgutier@umich.edu * void insertBlock(); 7410263Satgutier@umich.edu * void invalidate(); 7510263Satgutier@umich.edu */ 7610263Satgutier@umich.educlass BaseSetAssoc : public BaseTags 7710263Satgutier@umich.edu{ 7810263Satgutier@umich.edu public: 7910263Satgutier@umich.edu /** Typedef the block type used in this tag store. */ 8010263Satgutier@umich.edu typedef CacheBlk BlkType; 8110263Satgutier@umich.edu /** Typedef for a list of pointers to the local block class. */ 8210263Satgutier@umich.edu typedef std::list<BlkType*> BlkList; 8310263Satgutier@umich.edu /** Typedef the set type used in this tag store. */ 8410263Satgutier@umich.edu typedef CacheSet<CacheBlk> SetType; 8510263Satgutier@umich.edu 8610263Satgutier@umich.edu 8710263Satgutier@umich.edu protected: 8810263Satgutier@umich.edu /** The associativity of the cache. */ 8910263Satgutier@umich.edu const unsigned assoc; 9010263Satgutier@umich.edu /** The number of sets in the cache. */ 9110263Satgutier@umich.edu const unsigned numSets; 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. */ 9610263Satgutier@umich.edu SetType *sets; 9710263Satgutier@umich.edu 9810263Satgutier@umich.edu /** The cache blocks. */ 9910263Satgutier@umich.edu BlkType *blks; 10010263Satgutier@umich.edu /** The data blocks, 1 per cache block. */ 10110263Satgutier@umich.edu uint8_t *dataBlks; 10210263Satgutier@umich.edu 10310263Satgutier@umich.edu /** The amount to shift the address to get the set. */ 10410263Satgutier@umich.edu int setShift; 10510263Satgutier@umich.edu /** The amount to shift the address to get the tag. */ 10610263Satgutier@umich.edu int tagShift; 10710263Satgutier@umich.edu /** Mask out all bits that aren't part of the set index. */ 10810263Satgutier@umich.edu unsigned setMask; 10910263Satgutier@umich.edu /** Mask out all bits that aren't part of the block offset. */ 11010263Satgutier@umich.edu unsigned blkMask; 11110263Satgutier@umich.edu 11210263Satgutier@umich.edupublic: 11310263Satgutier@umich.edu 11410263Satgutier@umich.edu /** Convenience typedef. */ 11510263Satgutier@umich.edu typedef BaseSetAssocParams Params; 11610263Satgutier@umich.edu 11710263Satgutier@umich.edu /** 11810263Satgutier@umich.edu * Construct and initialize this tag store. 11910263Satgutier@umich.edu */ 12010263Satgutier@umich.edu BaseSetAssoc(const Params *p); 12110263Satgutier@umich.edu 12210263Satgutier@umich.edu /** 12310263Satgutier@umich.edu * Destructor 12410263Satgutier@umich.edu */ 12510263Satgutier@umich.edu virtual ~BaseSetAssoc(); 12610263Satgutier@umich.edu 12710263Satgutier@umich.edu /** 12810263Satgutier@umich.edu * Return the block size. 12910263Satgutier@umich.edu * @return the block size. 13010263Satgutier@umich.edu */ 13110263Satgutier@umich.edu unsigned 13210263Satgutier@umich.edu getBlockSize() const 13310263Satgutier@umich.edu { 13410263Satgutier@umich.edu return blkSize; 13510263Satgutier@umich.edu } 13610263Satgutier@umich.edu 13710263Satgutier@umich.edu /** 13810263Satgutier@umich.edu * Return the subblock size. In the case of BaseSetAssoc it is always 13910263Satgutier@umich.edu * the block size. 14010263Satgutier@umich.edu * @return The block size. 14110263Satgutier@umich.edu */ 14210263Satgutier@umich.edu unsigned 14310263Satgutier@umich.edu getSubBlockSize() const 14410263Satgutier@umich.edu { 14510263Satgutier@umich.edu return blkSize; 14610263Satgutier@umich.edu } 14710263Satgutier@umich.edu 14810263Satgutier@umich.edu /** 14910263Satgutier@umich.edu * Invalidate the given block. 15010263Satgutier@umich.edu * @param blk The block to invalidate. 15110263Satgutier@umich.edu */ 15210263Satgutier@umich.edu void invalidate(BlkType *blk) 15310263Satgutier@umich.edu { 15410263Satgutier@umich.edu assert(blk); 15510263Satgutier@umich.edu assert(blk->isValid()); 15610263Satgutier@umich.edu tagsInUse--; 15710263Satgutier@umich.edu assert(blk->srcMasterId < cache->system->maxMasters()); 15810263Satgutier@umich.edu occupancies[blk->srcMasterId]--; 15910263Satgutier@umich.edu blk->srcMasterId = Request::invldMasterId; 16010263Satgutier@umich.edu blk->task_id = ContextSwitchTaskId::Unknown; 16110263Satgutier@umich.edu blk->tickInserted = curTick(); 16210263Satgutier@umich.edu } 16310263Satgutier@umich.edu 16410263Satgutier@umich.edu /** 16510263Satgutier@umich.edu * Access block and update replacement data. May not succeed, in which case 16610263Satgutier@umich.edu * NULL pointer is returned. This has all the implications of a cache 16710263Satgutier@umich.edu * access and should only be used as such. Returns the access latency as a 16810263Satgutier@umich.edu * side effect. 16910263Satgutier@umich.edu * @param addr The address to find. 17010263Satgutier@umich.edu * @param is_secure True if the target memory space is secure. 17110263Satgutier@umich.edu * @param asid The address space ID. 17210263Satgutier@umich.edu * @param lat The access latency. 17310263Satgutier@umich.edu * @return Pointer to the cache block if found. 17410263Satgutier@umich.edu */ 17510263Satgutier@umich.edu BlkType* accessBlock(Addr addr, bool is_secure, Cycles &lat, 17610263Satgutier@umich.edu int context_src) 17710263Satgutier@umich.edu { 17810263Satgutier@umich.edu Addr tag = extractTag(addr); 17910263Satgutier@umich.edu int set = extractSet(addr); 18010263Satgutier@umich.edu BlkType *blk = sets[set].findBlk(tag, is_secure); 18110263Satgutier@umich.edu lat = hitLatency; 18210263Satgutier@umich.edu 18310263Satgutier@umich.edu // Access all tags in parallel, hence one in each way. The data side 18410263Satgutier@umich.edu // either accesses all blocks in parallel, or one block sequentially on 18510263Satgutier@umich.edu // a hit. Sequential access with a miss doesn't access data. 18610263Satgutier@umich.edu tagAccesses += assoc; 18710263Satgutier@umich.edu if (sequentialAccess) { 18810263Satgutier@umich.edu if (blk != NULL) { 18910263Satgutier@umich.edu dataAccesses += 1; 19010263Satgutier@umich.edu } 19110263Satgutier@umich.edu } else { 19210263Satgutier@umich.edu dataAccesses += assoc; 19310263Satgutier@umich.edu } 19410263Satgutier@umich.edu 19510263Satgutier@umich.edu if (blk != NULL) { 19610263Satgutier@umich.edu if (blk->whenReady > curTick() 19710263Satgutier@umich.edu && cache->ticksToCycles(blk->whenReady - curTick()) 19810263Satgutier@umich.edu > hitLatency) { 19910263Satgutier@umich.edu lat = cache->ticksToCycles(blk->whenReady - curTick()); 20010263Satgutier@umich.edu } 20110263Satgutier@umich.edu blk->refCount += 1; 20210263Satgutier@umich.edu } 20310263Satgutier@umich.edu 20410263Satgutier@umich.edu return blk; 20510263Satgutier@umich.edu } 20610263Satgutier@umich.edu 20710263Satgutier@umich.edu /** 20810263Satgutier@umich.edu * Finds the given address in the cache, do not update replacement data. 20910263Satgutier@umich.edu * i.e. This is a no-side-effect find of a block. 21010263Satgutier@umich.edu * @param addr The address to find. 21110263Satgutier@umich.edu * @param is_secure True if the target memory space is secure. 21210263Satgutier@umich.edu * @param asid The address space ID. 21310263Satgutier@umich.edu * @return Pointer to the cache block if found. 21410263Satgutier@umich.edu */ 21510263Satgutier@umich.edu BlkType* findBlock(Addr addr, bool is_secure) const; 21610263Satgutier@umich.edu 21710263Satgutier@umich.edu /** 21810263Satgutier@umich.edu * Find an invalid block to evict for the address provided. 21910263Satgutier@umich.edu * If there are no invalid blocks, this will return the block 22010263Satgutier@umich.edu * in the least-recently-used position. 22110263Satgutier@umich.edu * @param addr The addr to a find a replacement candidate for. 22210263Satgutier@umich.edu * @return The candidate block. 22310263Satgutier@umich.edu */ 22410263Satgutier@umich.edu BlkType* findVictim(Addr addr) const 22510263Satgutier@umich.edu { 22610263Satgutier@umich.edu BlkType *blk = NULL; 22710263Satgutier@umich.edu int set = extractSet(addr); 22810263Satgutier@umich.edu 22910263Satgutier@umich.edu // prefer to evict an invalid block 23010263Satgutier@umich.edu for (int i = 0; i < assoc; ++i) { 23110263Satgutier@umich.edu blk = sets[set].blks[i]; 23210263Satgutier@umich.edu if (!blk->isValid()) { 23310263Satgutier@umich.edu break; 23410263Satgutier@umich.edu } 23510263Satgutier@umich.edu } 23610263Satgutier@umich.edu 23710263Satgutier@umich.edu return blk; 23810263Satgutier@umich.edu } 23910263Satgutier@umich.edu 24010263Satgutier@umich.edu /** 24110263Satgutier@umich.edu * Insert the new block into the cache. 24210263Satgutier@umich.edu * @param pkt Packet holding the address to update 24310263Satgutier@umich.edu * @param blk The block to update. 24410263Satgutier@umich.edu */ 24510263Satgutier@umich.edu void insertBlock(PacketPtr pkt, BlkType *blk) 24610263Satgutier@umich.edu { 24710263Satgutier@umich.edu Addr addr = pkt->getAddr(); 24810263Satgutier@umich.edu MasterID master_id = pkt->req->masterId(); 24910263Satgutier@umich.edu uint32_t task_id = pkt->req->taskId(); 25010274Smitch.hayenga@arm.com 25110263Satgutier@umich.edu if (!blk->isTouched) { 25210263Satgutier@umich.edu tagsInUse++; 25310263Satgutier@umich.edu blk->isTouched = true; 25410263Satgutier@umich.edu if (!warmedUp && tagsInUse.value() >= warmupBound) { 25510263Satgutier@umich.edu warmedUp = true; 25610263Satgutier@umich.edu warmupCycle = curTick(); 25710263Satgutier@umich.edu } 25810263Satgutier@umich.edu } 25910263Satgutier@umich.edu 26010263Satgutier@umich.edu // If we're replacing a block that was previously valid update 26110263Satgutier@umich.edu // stats for it. This can't be done in findBlock() because a 26210263Satgutier@umich.edu // found block might not actually be replaced there if the 26310263Satgutier@umich.edu // coherence protocol says it can't be. 26410263Satgutier@umich.edu if (blk->isValid()) { 26510263Satgutier@umich.edu replacements[0]++; 26610263Satgutier@umich.edu totalRefs += blk->refCount; 26710263Satgutier@umich.edu ++sampledRefs; 26810263Satgutier@umich.edu blk->refCount = 0; 26910263Satgutier@umich.edu 27010263Satgutier@umich.edu // deal with evicted block 27110263Satgutier@umich.edu assert(blk->srcMasterId < cache->system->maxMasters()); 27210263Satgutier@umich.edu occupancies[blk->srcMasterId]--; 27310263Satgutier@umich.edu 27410263Satgutier@umich.edu blk->invalidate(); 27510263Satgutier@umich.edu } 27610263Satgutier@umich.edu 27710263Satgutier@umich.edu blk->isTouched = true; 27810274Smitch.hayenga@arm.com 27910263Satgutier@umich.edu // Set tag for new block. Caller is responsible for setting status. 28010263Satgutier@umich.edu blk->tag = extractTag(addr); 28110263Satgutier@umich.edu 28210263Satgutier@umich.edu // deal with what we are bringing in 28310263Satgutier@umich.edu assert(master_id < cache->system->maxMasters()); 28410263Satgutier@umich.edu occupancies[master_id]++; 28510263Satgutier@umich.edu blk->srcMasterId = master_id; 28610263Satgutier@umich.edu blk->task_id = task_id; 28710263Satgutier@umich.edu blk->tickInserted = curTick(); 28810263Satgutier@umich.edu 28910263Satgutier@umich.edu // We only need to write into one tag and one data block. 29010263Satgutier@umich.edu tagAccesses += 1; 29110263Satgutier@umich.edu dataAccesses += 1; 29210263Satgutier@umich.edu } 29310263Satgutier@umich.edu 29410263Satgutier@umich.edu /** 29510263Satgutier@umich.edu * Generate the tag from the given address. 29610263Satgutier@umich.edu * @param addr The address to get the tag from. 29710263Satgutier@umich.edu * @return The tag of the address. 29810263Satgutier@umich.edu */ 29910263Satgutier@umich.edu Addr extractTag(Addr addr) const 30010263Satgutier@umich.edu { 30110263Satgutier@umich.edu return (addr >> tagShift); 30210263Satgutier@umich.edu } 30310263Satgutier@umich.edu 30410263Satgutier@umich.edu /** 30510263Satgutier@umich.edu * Calculate the set index from the address. 30610263Satgutier@umich.edu * @param addr The address to get the set from. 30710263Satgutier@umich.edu * @return The set index of the address. 30810263Satgutier@umich.edu */ 30910263Satgutier@umich.edu int extractSet(Addr addr) const 31010263Satgutier@umich.edu { 31110263Satgutier@umich.edu return ((addr >> setShift) & setMask); 31210263Satgutier@umich.edu } 31310263Satgutier@umich.edu 31410263Satgutier@umich.edu /** 31510263Satgutier@umich.edu * Get the block offset from an address. 31610263Satgutier@umich.edu * @param addr The address to get the offset of. 31710263Satgutier@umich.edu * @return The block offset. 31810263Satgutier@umich.edu */ 31910263Satgutier@umich.edu int extractBlkOffset(Addr addr) const 32010263Satgutier@umich.edu { 32110263Satgutier@umich.edu return (addr & blkMask); 32210263Satgutier@umich.edu } 32310263Satgutier@umich.edu 32410263Satgutier@umich.edu /** 32510263Satgutier@umich.edu * Align an address to the block size. 32610263Satgutier@umich.edu * @param addr the address to align. 32710263Satgutier@umich.edu * @return The block address. 32810263Satgutier@umich.edu */ 32910263Satgutier@umich.edu Addr blkAlign(Addr addr) const 33010263Satgutier@umich.edu { 33110263Satgutier@umich.edu return (addr & ~(Addr)blkMask); 33210263Satgutier@umich.edu } 33310263Satgutier@umich.edu 33410263Satgutier@umich.edu /** 33510263Satgutier@umich.edu * Regenerate the block address from the tag. 33610263Satgutier@umich.edu * @param tag The tag of the block. 33710263Satgutier@umich.edu * @param set The set of the block. 33810263Satgutier@umich.edu * @return The block address. 33910263Satgutier@umich.edu */ 34010263Satgutier@umich.edu Addr regenerateBlkAddr(Addr tag, unsigned set) const 34110263Satgutier@umich.edu { 34210263Satgutier@umich.edu return ((tag << tagShift) | ((Addr)set << setShift)); 34310263Satgutier@umich.edu } 34410263Satgutier@umich.edu 34510263Satgutier@umich.edu /** 34610263Satgutier@umich.edu * Return the hit latency. 34710263Satgutier@umich.edu * @return the hit latency. 34810263Satgutier@umich.edu */ 34910263Satgutier@umich.edu Cycles getHitLatency() const 35010263Satgutier@umich.edu { 35110263Satgutier@umich.edu return hitLatency; 35210263Satgutier@umich.edu } 35310263Satgutier@umich.edu /** 35410263Satgutier@umich.edu *iterated through all blocks and clear all locks 35510263Satgutier@umich.edu *Needed to clear all lock tracking at once 35610263Satgutier@umich.edu */ 35710263Satgutier@umich.edu virtual void clearLocks(); 35810263Satgutier@umich.edu 35910263Satgutier@umich.edu /** 36010263Satgutier@umich.edu * Called at end of simulation to complete average block reference stats. 36110263Satgutier@umich.edu */ 36210263Satgutier@umich.edu virtual void cleanupRefs(); 36310263Satgutier@umich.edu 36410263Satgutier@umich.edu /** 36510263Satgutier@umich.edu * Print all tags used 36610263Satgutier@umich.edu */ 36710263Satgutier@umich.edu virtual std::string print() const; 36810263Satgutier@umich.edu 36910263Satgutier@umich.edu /** 37010263Satgutier@umich.edu * Called prior to dumping stats to compute task occupancy 37110263Satgutier@umich.edu */ 37210263Satgutier@umich.edu virtual void computeStats(); 37310263Satgutier@umich.edu 37410263Satgutier@umich.edu /** 37510263Satgutier@umich.edu * Visit each block in the tag store and apply a visitor to the 37610263Satgutier@umich.edu * block. 37710263Satgutier@umich.edu * 37810263Satgutier@umich.edu * The visitor should be a function (or object that behaves like a 37910263Satgutier@umich.edu * function) that takes a cache block reference as its parameter 38010263Satgutier@umich.edu * and returns a bool. A visitor can request the traversal to be 38110263Satgutier@umich.edu * stopped by returning false, returning true causes it to be 38210263Satgutier@umich.edu * called for the next block in the tag store. 38310263Satgutier@umich.edu * 38410263Satgutier@umich.edu * \param visitor Visitor to call on each block. 38510263Satgutier@umich.edu */ 38610263Satgutier@umich.edu template <typename V> 38710263Satgutier@umich.edu void forEachBlk(V &visitor) { 38810263Satgutier@umich.edu for (unsigned i = 0; i < numSets * assoc; ++i) { 38910263Satgutier@umich.edu if (!visitor(blks[i])) 39010263Satgutier@umich.edu return; 39110263Satgutier@umich.edu } 39210263Satgutier@umich.edu } 39310263Satgutier@umich.edu}; 39410263Satgutier@umich.edu 39510263Satgutier@umich.edu#endif // __MEM_CACHE_TAGS_BASESETASSOC_HH__ 396