snoop_filter.cc revision 14005
110399Sstephan.diestelhorst@arm.com/* 214005Stiago.muck@arm.com * Copyright (c) 2013-2017,2019 ARM Limited 310399Sstephan.diestelhorst@arm.com * All rights reserved 410399Sstephan.diestelhorst@arm.com * 510399Sstephan.diestelhorst@arm.com * The license below extends only to copyright in the software and shall 610399Sstephan.diestelhorst@arm.com * not be construed as granting a license to any other intellectual 710399Sstephan.diestelhorst@arm.com * property including but not limited to intellectual property relating 810399Sstephan.diestelhorst@arm.com * to a hardware implementation of the functionality of the software 910399Sstephan.diestelhorst@arm.com * licensed hereunder. You may use the software subject to the license 1010399Sstephan.diestelhorst@arm.com * terms below provided that you ensure that this notice is replicated 1110399Sstephan.diestelhorst@arm.com * unmodified and in its entirety in all distributions of the software, 1210399Sstephan.diestelhorst@arm.com * modified or unmodified, in source code or in binary form. 1310399Sstephan.diestelhorst@arm.com * 1410399Sstephan.diestelhorst@arm.com * Redistribution and use in source and binary forms, with or without 1510399Sstephan.diestelhorst@arm.com * modification, are permitted provided that the following conditions are 1610399Sstephan.diestelhorst@arm.com * met: redistributions of source code must retain the above copyright 1710399Sstephan.diestelhorst@arm.com * notice, this list of conditions and the following disclaimer; 1810399Sstephan.diestelhorst@arm.com * redistributions in binary form must reproduce the above copyright 1910399Sstephan.diestelhorst@arm.com * notice, this list of conditions and the following disclaimer in the 2010399Sstephan.diestelhorst@arm.com * documentation and/or other materials provided with the distribution; 2110399Sstephan.diestelhorst@arm.com * neither the name of the copyright holders nor the names of its 2210399Sstephan.diestelhorst@arm.com * contributors may be used to endorse or promote products derived from 2310399Sstephan.diestelhorst@arm.com * this software without specific prior written permission. 2410399Sstephan.diestelhorst@arm.com * 2510399Sstephan.diestelhorst@arm.com * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 2610399Sstephan.diestelhorst@arm.com * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 2710399Sstephan.diestelhorst@arm.com * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 2810399Sstephan.diestelhorst@arm.com * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 2910399Sstephan.diestelhorst@arm.com * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 3010399Sstephan.diestelhorst@arm.com * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 3110399Sstephan.diestelhorst@arm.com * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 3210399Sstephan.diestelhorst@arm.com * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 3310399Sstephan.diestelhorst@arm.com * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 3410399Sstephan.diestelhorst@arm.com * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 3510399Sstephan.diestelhorst@arm.com * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 3610399Sstephan.diestelhorst@arm.com * 3711135Sandreas.hansson@arm.com * Authors: Stephan Diestelhorst 3810399Sstephan.diestelhorst@arm.com */ 3910399Sstephan.diestelhorst@arm.com 4010399Sstephan.diestelhorst@arm.com/** 4110399Sstephan.diestelhorst@arm.com * @file 4211135Sandreas.hansson@arm.com * Implementation of a snoop filter. 4310399Sstephan.diestelhorst@arm.com */ 4410399Sstephan.diestelhorst@arm.com 4511793Sbrandon.potter@amd.com#include "mem/snoop_filter.hh" 4611793Sbrandon.potter@amd.com 4712334Sgabeblack@google.com#include "base/logging.hh" 4810399Sstephan.diestelhorst@arm.com#include "base/trace.hh" 4910399Sstephan.diestelhorst@arm.com#include "debug/SnoopFilter.hh" 5010399Sstephan.diestelhorst@arm.com#include "sim/system.hh" 5110399Sstephan.diestelhorst@arm.com 5214005Stiago.muck@arm.comconst int SnoopFilter::SNOOP_MASK_SIZE; 5314005Stiago.muck@arm.com 5411129Sali.jafri@arm.comvoid 5511129Sali.jafri@arm.comSnoopFilter::eraseIfNullEntry(SnoopFilterCache::iterator& sf_it) 5611129Sali.jafri@arm.com{ 5711129Sali.jafri@arm.com SnoopItem& sf_item = sf_it->second; 5814005Stiago.muck@arm.com if ((sf_item.requested | sf_item.holder).none()) { 5911129Sali.jafri@arm.com cachedLocations.erase(sf_it); 6011129Sali.jafri@arm.com DPRINTF(SnoopFilter, "%s: Removed SF entry.\n", 6111129Sali.jafri@arm.com __func__); 6211129Sali.jafri@arm.com } 6311129Sali.jafri@arm.com} 6411129Sali.jafri@arm.com 6510399Sstephan.diestelhorst@arm.comstd::pair<SnoopFilter::SnoopList, Cycles> 6610399Sstephan.diestelhorst@arm.comSnoopFilter::lookupRequest(const Packet* cpkt, const SlavePort& slave_port) 6710399Sstephan.diestelhorst@arm.com{ 6811744Snikos.nikoleris@arm.com DPRINTF(SnoopFilter, "%s: src %s packet %s\n", __func__, 6911744Snikos.nikoleris@arm.com slave_port.name(), cpkt->print()); 7010399Sstephan.diestelhorst@arm.com 7111603Sandreas.hansson@arm.com // check if the packet came from a cache 7211603Sandreas.hansson@arm.com bool allocate = !cpkt->req->isUncacheable() && slave_port.isSnooping() && 7311603Sandreas.hansson@arm.com cpkt->fromCache(); 7411128Sali.jafri@arm.com Addr line_addr = cpkt->getBlockAddr(linesize); 7511605Snikos.nikoleris@arm.com if (cpkt->isSecure()) { 7611605Snikos.nikoleris@arm.com line_addr |= LineSecure; 7711605Snikos.nikoleris@arm.com } 7810399Sstephan.diestelhorst@arm.com SnoopMask req_port = portToMask(slave_port); 7911131Sandreas.hansson@arm.com reqLookupResult = cachedLocations.find(line_addr); 8011131Sandreas.hansson@arm.com bool is_hit = (reqLookupResult != cachedLocations.end()); 8111128Sali.jafri@arm.com 8211128Sali.jafri@arm.com // If the snoop filter has no entry, and we should not allocate, 8311128Sali.jafri@arm.com // do not create a new snoop filter entry, simply return a NULL 8411128Sali.jafri@arm.com // portlist. 8511128Sali.jafri@arm.com if (!is_hit && !allocate) 8611128Sali.jafri@arm.com return snoopDown(lookupLatency); 8711128Sali.jafri@arm.com 8811131Sandreas.hansson@arm.com // If no hit in snoop filter create a new element and update iterator 8911131Sandreas.hansson@arm.com if (!is_hit) 9011131Sandreas.hansson@arm.com reqLookupResult = cachedLocations.emplace(line_addr, SnoopItem()).first; 9111131Sandreas.hansson@arm.com SnoopItem& sf_item = reqLookupResult->second; 9210403Sstephan.diestelhorst@arm.com SnoopMask interested = sf_item.holder | sf_item.requested; 9310403Sstephan.diestelhorst@arm.com 9411129Sali.jafri@arm.com // Store unmodified value of snoop filter item in temp storage in 9511129Sali.jafri@arm.com // case we need to revert because of a send retry in 9611129Sali.jafri@arm.com // updateRequest. 9711129Sali.jafri@arm.com retryItem = sf_item; 9811129Sali.jafri@arm.com 9910403Sstephan.diestelhorst@arm.com totRequests++; 10010403Sstephan.diestelhorst@arm.com if (is_hit) { 10114005Stiago.muck@arm.com if (interested.count() == 1) 10210403Sstephan.diestelhorst@arm.com hitSingleRequests++; 10310403Sstephan.diestelhorst@arm.com else 10410403Sstephan.diestelhorst@arm.com hitMultiRequests++; 10510403Sstephan.diestelhorst@arm.com } 10610399Sstephan.diestelhorst@arm.com 10710399Sstephan.diestelhorst@arm.com DPRINTF(SnoopFilter, "%s: SF value %x.%x\n", 10810399Sstephan.diestelhorst@arm.com __func__, sf_item.requested, sf_item.holder); 10910399Sstephan.diestelhorst@arm.com 11011129Sali.jafri@arm.com // If we are not allocating, we are done 11111129Sali.jafri@arm.com if (!allocate) 11211129Sali.jafri@arm.com return snoopSelected(maskToPortList(interested & ~req_port), 11311129Sali.jafri@arm.com lookupLatency); 11411129Sali.jafri@arm.com 11511129Sali.jafri@arm.com if (cpkt->needsResponse()) { 11611284Sandreas.hansson@arm.com if (!cpkt->cacheResponding()) { 11710399Sstephan.diestelhorst@arm.com // Max one request per address per port 11814005Stiago.muck@arm.com panic_if((sf_item.requested & req_port).any(), 11914005Stiago.muck@arm.com "double request :( SF value %x.%x\n", 12014005Stiago.muck@arm.com sf_item.requested, sf_item.holder); 12110399Sstephan.diestelhorst@arm.com 12210399Sstephan.diestelhorst@arm.com // Mark in-flight requests to distinguish later on 12310399Sstephan.diestelhorst@arm.com sf_item.requested |= req_port; 12411129Sali.jafri@arm.com DPRINTF(SnoopFilter, "%s: new SF value %x.%x\n", 12511129Sali.jafri@arm.com __func__, sf_item.requested, sf_item.holder); 12610399Sstephan.diestelhorst@arm.com } else { 12710399Sstephan.diestelhorst@arm.com // NOTE: The memInhibit might have been asserted by a cache closer 12810399Sstephan.diestelhorst@arm.com // to the CPU, already -> the response will not be seen by this 12910399Sstephan.diestelhorst@arm.com // filter -> we do not need to keep the in-flight request, but make 13010399Sstephan.diestelhorst@arm.com // sure that we know that that cluster has a copy 13114005Stiago.muck@arm.com panic_if((sf_item.holder & req_port).none(), 13214005Stiago.muck@arm.com "Need to hold the value!"); 13311129Sali.jafri@arm.com DPRINTF(SnoopFilter, 13411129Sali.jafri@arm.com "%s: not marking request. SF value %x.%x\n", 13510399Sstephan.diestelhorst@arm.com __func__, sf_item.requested, sf_item.holder); 13610399Sstephan.diestelhorst@arm.com } 13711129Sali.jafri@arm.com } else { // if (!cpkt->needsResponse()) 13811199Sandreas.hansson@arm.com assert(cpkt->isEviction()); 13911129Sali.jafri@arm.com // make sure that the sender actually had the line 14014005Stiago.muck@arm.com panic_if((sf_item.holder & req_port).none(), "requester %x is not a " \ 14111129Sali.jafri@arm.com "holder :( SF value %x.%x\n", req_port, 14211129Sali.jafri@arm.com sf_item.requested, sf_item.holder); 14311129Sali.jafri@arm.com // CleanEvicts and Writebacks -> the sender and all caches above 14411129Sali.jafri@arm.com // it may not have the line anymore. 14511129Sali.jafri@arm.com if (!cpkt->isBlockCached()) { 14611129Sali.jafri@arm.com sf_item.holder &= ~req_port; 14711129Sali.jafri@arm.com DPRINTF(SnoopFilter, "%s: new SF value %x.%x\n", 14811129Sali.jafri@arm.com __func__, sf_item.requested, sf_item.holder); 14911129Sali.jafri@arm.com } 15010399Sstephan.diestelhorst@arm.com } 15111129Sali.jafri@arm.com 15210403Sstephan.diestelhorst@arm.com return snoopSelected(maskToPortList(interested & ~req_port), lookupLatency); 15310399Sstephan.diestelhorst@arm.com} 15410399Sstephan.diestelhorst@arm.com 15510399Sstephan.diestelhorst@arm.comvoid 15611605Snikos.nikoleris@arm.comSnoopFilter::finishRequest(bool will_retry, Addr addr, bool is_secure) 15710399Sstephan.diestelhorst@arm.com{ 15811131Sandreas.hansson@arm.com if (reqLookupResult != cachedLocations.end()) { 15911131Sandreas.hansson@arm.com // since we rely on the caller, do a basic check to ensure 16011131Sandreas.hansson@arm.com // that finishRequest is being called following lookupRequest 16111605Snikos.nikoleris@arm.com Addr line_addr = (addr & ~(Addr(linesize - 1))); 16211605Snikos.nikoleris@arm.com if (is_secure) { 16311605Snikos.nikoleris@arm.com line_addr |= LineSecure; 16411605Snikos.nikoleris@arm.com } 16511605Snikos.nikoleris@arm.com assert(reqLookupResult->first == line_addr); 16611131Sandreas.hansson@arm.com if (will_retry) { 16711131Sandreas.hansson@arm.com // Undo any changes made in lookupRequest to the snoop filter 16811131Sandreas.hansson@arm.com // entry if the request will come again. retryItem holds 16911131Sandreas.hansson@arm.com // the previous value of the snoopfilter entry. 17011131Sandreas.hansson@arm.com reqLookupResult->second = retryItem; 17110399Sstephan.diestelhorst@arm.com 17211131Sandreas.hansson@arm.com DPRINTF(SnoopFilter, "%s: restored SF value %x.%x\n", 17311131Sandreas.hansson@arm.com __func__, retryItem.requested, retryItem.holder); 17411131Sandreas.hansson@arm.com } 17510821Sandreas.hansson@arm.com 17611131Sandreas.hansson@arm.com eraseIfNullEntry(reqLookupResult); 17710399Sstephan.diestelhorst@arm.com } 17810399Sstephan.diestelhorst@arm.com} 17910399Sstephan.diestelhorst@arm.com 18010399Sstephan.diestelhorst@arm.comstd::pair<SnoopFilter::SnoopList, Cycles> 18110399Sstephan.diestelhorst@arm.comSnoopFilter::lookupSnoop(const Packet* cpkt) 18210399Sstephan.diestelhorst@arm.com{ 18311744Snikos.nikoleris@arm.com DPRINTF(SnoopFilter, "%s: packet %s\n", __func__, cpkt->print()); 18410399Sstephan.diestelhorst@arm.com 18510399Sstephan.diestelhorst@arm.com assert(cpkt->isRequest()); 18610399Sstephan.diestelhorst@arm.com 18711128Sali.jafri@arm.com Addr line_addr = cpkt->getBlockAddr(linesize); 18811605Snikos.nikoleris@arm.com if (cpkt->isSecure()) { 18911605Snikos.nikoleris@arm.com line_addr |= LineSecure; 19011605Snikos.nikoleris@arm.com } 19110403Sstephan.diestelhorst@arm.com auto sf_it = cachedLocations.find(line_addr); 19210403Sstephan.diestelhorst@arm.com bool is_hit = (sf_it != cachedLocations.end()); 19311129Sali.jafri@arm.com 19411132Sali.jafri@arm.com panic_if(!is_hit && (cachedLocations.size() >= maxEntryCount), 19511132Sali.jafri@arm.com "snoop filter exceeded capacity of %d cache blocks\n", 19611132Sali.jafri@arm.com maxEntryCount); 19711132Sali.jafri@arm.com 19811134Sandreas.hansson@arm.com // If the snoop filter has no entry, simply return a NULL 19911134Sandreas.hansson@arm.com // portlist, there is no point creating an entry only to remove it 20011134Sandreas.hansson@arm.com // later 20111134Sandreas.hansson@arm.com if (!is_hit) 20211129Sali.jafri@arm.com return snoopDown(lookupLatency); 20311129Sali.jafri@arm.com 20411129Sali.jafri@arm.com SnoopItem& sf_item = sf_it->second; 20510399Sstephan.diestelhorst@arm.com 20610399Sstephan.diestelhorst@arm.com DPRINTF(SnoopFilter, "%s: old SF value %x.%x\n", 20710399Sstephan.diestelhorst@arm.com __func__, sf_item.requested, sf_item.holder); 20810399Sstephan.diestelhorst@arm.com 20910399Sstephan.diestelhorst@arm.com SnoopMask interested = (sf_item.holder | sf_item.requested); 21010403Sstephan.diestelhorst@arm.com 21110403Sstephan.diestelhorst@arm.com totSnoops++; 21214005Stiago.muck@arm.com 21314005Stiago.muck@arm.com if (interested.count() == 1) 21411134Sandreas.hansson@arm.com hitSingleSnoops++; 21511134Sandreas.hansson@arm.com else 21611134Sandreas.hansson@arm.com hitMultiSnoops++; 21711134Sandreas.hansson@arm.com 21810883Sali.jafri@arm.com // ReadEx and Writes require both invalidation and exlusivity, while reads 21910883Sali.jafri@arm.com // require neither. Writebacks on the other hand require exclusivity but 22010883Sali.jafri@arm.com // not the invalidation. Previously Writebacks did not generate upward 22112352Snikos.nikoleris@arm.com // snoops so this was never an issue. Now that Writebacks generate snoops 22212352Snikos.nikoleris@arm.com // we need a special case for Writebacks. Additionally cache maintenance 22312352Snikos.nikoleris@arm.com // operations can generate snoops as they clean and/or invalidate all 22412352Snikos.nikoleris@arm.com // caches down to the specified point of reference. 22511199Sandreas.hansson@arm.com assert(cpkt->isWriteback() || cpkt->req->isUncacheable() || 22612352Snikos.nikoleris@arm.com (cpkt->isInvalidate() == cpkt->needsWritable()) || 22712352Snikos.nikoleris@arm.com cpkt->req->isCacheMaintenance()); 22814005Stiago.muck@arm.com if (cpkt->isInvalidate() && sf_item.requested.none()) { 22910399Sstephan.diestelhorst@arm.com // Early clear of the holder, if no other request is currently going on 23010399Sstephan.diestelhorst@arm.com // @todo: This should possibly be updated even though we do not filter 23110399Sstephan.diestelhorst@arm.com // upward snoops 23210399Sstephan.diestelhorst@arm.com sf_item.holder = 0; 23310399Sstephan.diestelhorst@arm.com } 23410399Sstephan.diestelhorst@arm.com 23511129Sali.jafri@arm.com eraseIfNullEntry(sf_it); 23610399Sstephan.diestelhorst@arm.com DPRINTF(SnoopFilter, "%s: new SF value %x.%x interest: %x \n", 23710399Sstephan.diestelhorst@arm.com __func__, sf_item.requested, sf_item.holder, interested); 23810399Sstephan.diestelhorst@arm.com 23910399Sstephan.diestelhorst@arm.com return snoopSelected(maskToPortList(interested), lookupLatency); 24010399Sstephan.diestelhorst@arm.com} 24110399Sstephan.diestelhorst@arm.com 24210399Sstephan.diestelhorst@arm.comvoid 24310399Sstephan.diestelhorst@arm.comSnoopFilter::updateSnoopResponse(const Packet* cpkt, 24410399Sstephan.diestelhorst@arm.com const SlavePort& rsp_port, 24510399Sstephan.diestelhorst@arm.com const SlavePort& req_port) 24610399Sstephan.diestelhorst@arm.com{ 24711744Snikos.nikoleris@arm.com DPRINTF(SnoopFilter, "%s: rsp %s req %s packet %s\n", 24811744Snikos.nikoleris@arm.com __func__, rsp_port.name(), req_port.name(), cpkt->print()); 24910399Sstephan.diestelhorst@arm.com 25010821Sandreas.hansson@arm.com assert(cpkt->isResponse()); 25111284Sandreas.hansson@arm.com assert(cpkt->cacheResponding()); 25210821Sandreas.hansson@arm.com 25311603Sandreas.hansson@arm.com // if this snoop response is due to an uncacheable request, or is 25411603Sandreas.hansson@arm.com // being turned into a normal response, there is nothing more to 25511603Sandreas.hansson@arm.com // do 25611603Sandreas.hansson@arm.com if (cpkt->req->isUncacheable() || !req_port.isSnooping()) { 25710821Sandreas.hansson@arm.com return; 25811603Sandreas.hansson@arm.com } 25910821Sandreas.hansson@arm.com 26011128Sali.jafri@arm.com Addr line_addr = cpkt->getBlockAddr(linesize); 26111605Snikos.nikoleris@arm.com if (cpkt->isSecure()) { 26211605Snikos.nikoleris@arm.com line_addr |= LineSecure; 26311605Snikos.nikoleris@arm.com } 26410399Sstephan.diestelhorst@arm.com SnoopMask rsp_mask = portToMask(rsp_port); 26510399Sstephan.diestelhorst@arm.com SnoopMask req_mask = portToMask(req_port); 26610399Sstephan.diestelhorst@arm.com SnoopItem& sf_item = cachedLocations[line_addr]; 26710399Sstephan.diestelhorst@arm.com 26810399Sstephan.diestelhorst@arm.com DPRINTF(SnoopFilter, "%s: old SF value %x.%x\n", 26910399Sstephan.diestelhorst@arm.com __func__, sf_item.requested, sf_item.holder); 27010399Sstephan.diestelhorst@arm.com 27110399Sstephan.diestelhorst@arm.com // The source should have the line 27214005Stiago.muck@arm.com panic_if((sf_item.holder & rsp_mask).none(), 27314005Stiago.muck@arm.com "SF value %x.%x does not have the line\n", 27414005Stiago.muck@arm.com sf_item.requested, sf_item.holder); 27510399Sstephan.diestelhorst@arm.com 27610399Sstephan.diestelhorst@arm.com // The destination should have had a request in 27714005Stiago.muck@arm.com panic_if((sf_item.requested & req_mask).none(), "SF value %x.%x missing "\ 27810399Sstephan.diestelhorst@arm.com "the original request\n", sf_item.requested, sf_item.holder); 27910399Sstephan.diestelhorst@arm.com 28011287Sandreas.hansson@arm.com // If the snoop response has no sharers the line is passed in 28111287Sandreas.hansson@arm.com // Modified state, and we know that there are no other copies, or 28211287Sandreas.hansson@arm.com // they will all be invalidated imminently 28311287Sandreas.hansson@arm.com if (!cpkt->hasSharers()) { 28411287Sandreas.hansson@arm.com DPRINTF(SnoopFilter, 28511287Sandreas.hansson@arm.com "%s: dropping %x because non-shared snoop " 28611287Sandreas.hansson@arm.com "response SF val: %x.%x\n", __func__, rsp_mask, 28710399Sstephan.diestelhorst@arm.com sf_item.requested, sf_item.holder); 28810399Sstephan.diestelhorst@arm.com sf_item.holder = 0; 28910399Sstephan.diestelhorst@arm.com } 29011199Sandreas.hansson@arm.com assert(!cpkt->isWriteback()); 29111603Sandreas.hansson@arm.com // @todo Deal with invalidating responses 29210399Sstephan.diestelhorst@arm.com sf_item.holder |= req_mask; 29310399Sstephan.diestelhorst@arm.com sf_item.requested &= ~req_mask; 29414005Stiago.muck@arm.com assert((sf_item.requested | sf_item.holder).any()); 29510399Sstephan.diestelhorst@arm.com DPRINTF(SnoopFilter, "%s: new SF value %x.%x\n", 29610399Sstephan.diestelhorst@arm.com __func__, sf_item.requested, sf_item.holder); 29710399Sstephan.diestelhorst@arm.com} 29810399Sstephan.diestelhorst@arm.com 29910399Sstephan.diestelhorst@arm.comvoid 30010399Sstephan.diestelhorst@arm.comSnoopFilter::updateSnoopForward(const Packet* cpkt, 30110399Sstephan.diestelhorst@arm.com const SlavePort& rsp_port, const MasterPort& req_port) 30210399Sstephan.diestelhorst@arm.com{ 30311744Snikos.nikoleris@arm.com DPRINTF(SnoopFilter, "%s: rsp %s req %s packet %s\n", 30411744Snikos.nikoleris@arm.com __func__, rsp_port.name(), req_port.name(), cpkt->print()); 30510399Sstephan.diestelhorst@arm.com 30611134Sandreas.hansson@arm.com assert(cpkt->isResponse()); 30711284Sandreas.hansson@arm.com assert(cpkt->cacheResponding()); 30811134Sandreas.hansson@arm.com 30911128Sali.jafri@arm.com Addr line_addr = cpkt->getBlockAddr(linesize); 31011605Snikos.nikoleris@arm.com if (cpkt->isSecure()) { 31111605Snikos.nikoleris@arm.com line_addr |= LineSecure; 31211605Snikos.nikoleris@arm.com } 31311129Sali.jafri@arm.com auto sf_it = cachedLocations.find(line_addr); 31411134Sandreas.hansson@arm.com bool is_hit = sf_it != cachedLocations.end(); 31511134Sandreas.hansson@arm.com 31611134Sandreas.hansson@arm.com // Nothing to do if it is not a hit 31711134Sandreas.hansson@arm.com if (!is_hit) 31811134Sandreas.hansson@arm.com return; 31911134Sandreas.hansson@arm.com 32011129Sali.jafri@arm.com SnoopItem& sf_item = sf_it->second; 32110399Sstephan.diestelhorst@arm.com 32210399Sstephan.diestelhorst@arm.com DPRINTF(SnoopFilter, "%s: old SF value %x.%x\n", 32310399Sstephan.diestelhorst@arm.com __func__, sf_item.requested, sf_item.holder); 32410399Sstephan.diestelhorst@arm.com 32511287Sandreas.hansson@arm.com // If the snoop response has no sharers the line is passed in 32611287Sandreas.hansson@arm.com // Modified state, and we know that there are no other copies, or 32711287Sandreas.hansson@arm.com // they will all be invalidated imminently 32811287Sandreas.hansson@arm.com if (!cpkt->hasSharers()) { 32910399Sstephan.diestelhorst@arm.com sf_item.holder = 0; 33010399Sstephan.diestelhorst@arm.com } 33110399Sstephan.diestelhorst@arm.com DPRINTF(SnoopFilter, "%s: new SF value %x.%x\n", 33210399Sstephan.diestelhorst@arm.com __func__, sf_item.requested, sf_item.holder); 33311129Sali.jafri@arm.com eraseIfNullEntry(sf_it); 33411134Sandreas.hansson@arm.com 33510399Sstephan.diestelhorst@arm.com} 33610399Sstephan.diestelhorst@arm.com 33710399Sstephan.diestelhorst@arm.comvoid 33810399Sstephan.diestelhorst@arm.comSnoopFilter::updateResponse(const Packet* cpkt, const SlavePort& slave_port) 33910399Sstephan.diestelhorst@arm.com{ 34011744Snikos.nikoleris@arm.com DPRINTF(SnoopFilter, "%s: src %s packet %s\n", 34111744Snikos.nikoleris@arm.com __func__, slave_port.name(), cpkt->print()); 34210399Sstephan.diestelhorst@arm.com 34310821Sandreas.hansson@arm.com assert(cpkt->isResponse()); 34410821Sandreas.hansson@arm.com 34511603Sandreas.hansson@arm.com // we only allocate if the packet actually came from a cache, but 34611603Sandreas.hansson@arm.com // start by checking if the port is snooping 34711603Sandreas.hansson@arm.com if (cpkt->req->isUncacheable() || !slave_port.isSnooping()) 34810821Sandreas.hansson@arm.com return; 34910821Sandreas.hansson@arm.com 35011603Sandreas.hansson@arm.com // next check if we actually allocated an entry 35111128Sali.jafri@arm.com Addr line_addr = cpkt->getBlockAddr(linesize); 35211605Snikos.nikoleris@arm.com if (cpkt->isSecure()) { 35311605Snikos.nikoleris@arm.com line_addr |= LineSecure; 35411605Snikos.nikoleris@arm.com } 35511603Sandreas.hansson@arm.com auto sf_it = cachedLocations.find(line_addr); 35611603Sandreas.hansson@arm.com if (sf_it == cachedLocations.end()) 35711603Sandreas.hansson@arm.com return; 35811603Sandreas.hansson@arm.com 35910399Sstephan.diestelhorst@arm.com SnoopMask slave_mask = portToMask(slave_port); 36011603Sandreas.hansson@arm.com SnoopItem& sf_item = sf_it->second; 36110399Sstephan.diestelhorst@arm.com 36210399Sstephan.diestelhorst@arm.com DPRINTF(SnoopFilter, "%s: old SF value %x.%x\n", 36310399Sstephan.diestelhorst@arm.com __func__, sf_item.requested, sf_item.holder); 36410399Sstephan.diestelhorst@arm.com 36510399Sstephan.diestelhorst@arm.com // Make sure we have seen the actual request, too 36614005Stiago.muck@arm.com panic_if((sf_item.requested & slave_mask).none(), 36714005Stiago.muck@arm.com "SF value %x.%x missing request bit\n", 36814005Stiago.muck@arm.com sf_item.requested, sf_item.holder); 36910399Sstephan.diestelhorst@arm.com 37012353Snikos.nikoleris@arm.com sf_item.requested &= ~slave_mask; 37111748Snikos.nikoleris@arm.com // Update the residency of the cache line. 37212353Snikos.nikoleris@arm.com 37312353Snikos.nikoleris@arm.com if (cpkt->req->isCacheMaintenance()) { 37412353Snikos.nikoleris@arm.com // A cache clean response does not carry any data so it 37512353Snikos.nikoleris@arm.com // shouldn't change the holders, unless it is invalidating. 37612353Snikos.nikoleris@arm.com if (cpkt->isInvalidate()) { 37712353Snikos.nikoleris@arm.com sf_item.holder &= ~slave_mask; 37812353Snikos.nikoleris@arm.com } 37912353Snikos.nikoleris@arm.com eraseIfNullEntry(sf_it); 38012353Snikos.nikoleris@arm.com } else { 38112353Snikos.nikoleris@arm.com // Any other response implies that a cache above will have the 38212353Snikos.nikoleris@arm.com // block. 38312353Snikos.nikoleris@arm.com sf_item.holder |= slave_mask; 38414005Stiago.muck@arm.com assert((sf_item.holder | sf_item.requested).any()); 38512353Snikos.nikoleris@arm.com } 38610399Sstephan.diestelhorst@arm.com DPRINTF(SnoopFilter, "%s: new SF value %x.%x\n", 38710399Sstephan.diestelhorst@arm.com __func__, sf_item.requested, sf_item.holder); 38810399Sstephan.diestelhorst@arm.com} 38910399Sstephan.diestelhorst@arm.com 39010403Sstephan.diestelhorst@arm.comvoid 39110403Sstephan.diestelhorst@arm.comSnoopFilter::regStats() 39210403Sstephan.diestelhorst@arm.com{ 39311523Sdavid.guillen@arm.com SimObject::regStats(); 39411523Sdavid.guillen@arm.com 39510403Sstephan.diestelhorst@arm.com totRequests 39610403Sstephan.diestelhorst@arm.com .name(name() + ".tot_requests") 39710403Sstephan.diestelhorst@arm.com .desc("Total number of requests made to the snoop filter."); 39810403Sstephan.diestelhorst@arm.com 39910403Sstephan.diestelhorst@arm.com hitSingleRequests 40010403Sstephan.diestelhorst@arm.com .name(name() + ".hit_single_requests") 40110403Sstephan.diestelhorst@arm.com .desc("Number of requests hitting in the snoop filter with a single "\ 40210403Sstephan.diestelhorst@arm.com "holder of the requested data."); 40310403Sstephan.diestelhorst@arm.com 40410403Sstephan.diestelhorst@arm.com hitMultiRequests 40510403Sstephan.diestelhorst@arm.com .name(name() + ".hit_multi_requests") 40610403Sstephan.diestelhorst@arm.com .desc("Number of requests hitting in the snoop filter with multiple "\ 40710403Sstephan.diestelhorst@arm.com "(>1) holders of the requested data."); 40810403Sstephan.diestelhorst@arm.com 40910403Sstephan.diestelhorst@arm.com totSnoops 41010403Sstephan.diestelhorst@arm.com .name(name() + ".tot_snoops") 41110403Sstephan.diestelhorst@arm.com .desc("Total number of snoops made to the snoop filter."); 41210403Sstephan.diestelhorst@arm.com 41310403Sstephan.diestelhorst@arm.com hitSingleSnoops 41410403Sstephan.diestelhorst@arm.com .name(name() + ".hit_single_snoops") 41510403Sstephan.diestelhorst@arm.com .desc("Number of snoops hitting in the snoop filter with a single "\ 41610403Sstephan.diestelhorst@arm.com "holder of the requested data."); 41710403Sstephan.diestelhorst@arm.com 41810403Sstephan.diestelhorst@arm.com hitMultiSnoops 41910403Sstephan.diestelhorst@arm.com .name(name() + ".hit_multi_snoops") 42010403Sstephan.diestelhorst@arm.com .desc("Number of snoops hitting in the snoop filter with multiple "\ 42110403Sstephan.diestelhorst@arm.com "(>1) holders of the requested data."); 42210403Sstephan.diestelhorst@arm.com} 42310403Sstephan.diestelhorst@arm.com 42410399Sstephan.diestelhorst@arm.comSnoopFilter * 42510399Sstephan.diestelhorst@arm.comSnoopFilterParams::create() 42610399Sstephan.diestelhorst@arm.com{ 42710399Sstephan.diestelhorst@arm.com return new SnoopFilter(this); 42810399Sstephan.diestelhorst@arm.com} 429