From 28fd4ab39fe7991d335e8496ed2b3434db61140d Mon Sep 17 00:00:00 2001 From: Ron Dreslinski Date: Wed, 22 Nov 2006 20:20:38 -0500 Subject: Do a functional access to levels above on a read as a temporary solution for L2's in FS Fix a small writeback bug when missing in the L2 in atomic mode src/mem/bus.cc: Fix a comment to make sense src/mem/cache/cache_impl.hh: Do a functional access to levels above on a read as a temporary solution for L2's in FS Also fix a small writeback miss in L2 issue src/mem/cache/coherence/simple_coherence.hh: src/mem/cache/coherence/uni_coherence.cc: src/mem/cache/coherence/uni_coherence.hh: Do a functional access to levels above on a read as a temporary solution for L2's in FS tests/quick/00.hello/ref/alpha/linux/o3-timing/m5stats.txt: tests/quick/00.hello/ref/alpha/linux/simple-timing/m5stats.txt: tests/quick/01.hello-2T-smt/ref/alpha/linux/o3-timing/m5stats.txt: Update ref's for writeback changes --HG-- extra : convert_revision : 937febd577b16b7fd97a5a68acaf53541828a251 --- src/mem/bus.cc | 2 +- src/mem/cache/cache_impl.hh | 19 ++++++++++++--- src/mem/cache/coherence/simple_coherence.hh | 4 ++-- src/mem/cache/coherence/uni_coherence.cc | 37 +++++++++++++++++++++++++++-- src/mem/cache/coherence/uni_coherence.hh | 2 +- 5 files changed, 55 insertions(+), 9 deletions(-) (limited to 'src/mem') diff --git a/src/mem/bus.cc b/src/mem/bus.cc index 6b5b63f50..e9a870b80 100644 --- a/src/mem/bus.cc +++ b/src/mem/bus.cc @@ -296,7 +296,7 @@ Bus::findPort(Addr addr, int id) // we shouldn't be sending this back to where it came from - // only on a functional access and then we should terminate + // do the snoop access and then we should terminate // the cyclical call. if (dest_id == id) return 0; diff --git a/src/mem/cache/cache_impl.hh b/src/mem/cache/cache_impl.hh index df59b0a4f..3a681bc52 100644 --- a/src/mem/cache/cache_impl.hh +++ b/src/mem/cache/cache_impl.hh @@ -391,7 +391,13 @@ Cache::snoop(PacketPtr &pkt) } //Send a timing (true) invalidate up if the protocol calls for it - coherence->propogateInvalidate(pkt, true); + if (coherence->propogateInvalidate(pkt, true)) { + //Temp hack, we had a functional read hit in the L1, mark as success + pkt->flags |= SATISFIED; + pkt->result = Packet::Success; + respondToSnoop(pkt, curTick + hitLatency); + return; + } Addr blk_addr = pkt->getAddr() & ~(Addr(blkSize-1)); BlkType *blk = tags->findBlock(pkt); @@ -562,6 +568,7 @@ Cache::probe(PacketPtr &pkt, bool update, PacketList writebacks; int lat; + BlkType *blk = tags->handleAccess(pkt, lat, writebacks, update); DPRINTF(Cache, "%s %x %s\n", pkt->cmdString(), @@ -615,7 +622,8 @@ Cache::probe(PacketPtr &pkt, bool update, // Can't handle it, return request unsatisfied. panic("Atomic access ran into outstanding MSHR's or WB's!"); } - if (!pkt->req->isUncacheable()) { + if (!pkt->req->isUncacheable() /*Uncacheables just go through*/ + && (pkt->cmd != Packet::Writeback)/*Writebacks on miss fall through*/) { // Fetch the cache block to fill BlkType *blk = tags->findBlock(pkt); Packet::Command temp_cmd = coherence->getBusCmd(pkt->cmd, @@ -691,7 +699,12 @@ Tick Cache::snoopProbe(PacketPtr &pkt) { //Send a atomic (false) invalidate up if the protocol calls for it - coherence->propogateInvalidate(pkt, false); + if (coherence->propogateInvalidate(pkt, false)) { + //Temp hack, we had a functional read hit in the L1, mark as success + pkt->flags |= SATISFIED; + pkt->result = Packet::Success; + return hitLatency; + } Addr blk_addr = pkt->getAddr() & ~(Addr(blkSize-1)); BlkType *blk = tags->findBlock(pkt); diff --git a/src/mem/cache/coherence/simple_coherence.hh b/src/mem/cache/coherence/simple_coherence.hh index 5316e64b9..a1fd33080 100644 --- a/src/mem/cache/coherence/simple_coherence.hh +++ b/src/mem/cache/coherence/simple_coherence.hh @@ -161,10 +161,10 @@ class SimpleCoherence bool hasProtocol() { return true; } - void propogateInvalidate(PacketPtr pkt, bool isTiming) + bool propogateInvalidate(PacketPtr pkt, bool isTiming) { //For now we do nothing, asssumes simple coherence is top level of cache - return; + return false; } }; diff --git a/src/mem/cache/coherence/uni_coherence.cc b/src/mem/cache/coherence/uni_coherence.cc index 19230e35b..5813a0281 100644 --- a/src/mem/cache/coherence/uni_coherence.cc +++ b/src/mem/cache/coherence/uni_coherence.cc @@ -54,6 +54,7 @@ UniCoherence::sendResult(PacketPtr &pkt, MSHR* cshr, bool success) { bool unblock = cshrs.isFull(); // cshrs.markInService(cshr); + delete pkt->req; cshrs.deallocate(cshr); if (!cshrs.havePending()) { cache->clearSlaveRequest(Request_Coherence); @@ -81,17 +82,28 @@ UniCoherence::handleBusRequest(PacketPtr &pkt, CacheBlk *blk, MSHR *mshr, } else if (blk) { new_state = blk->status; + if (pkt->isRead()) { + DPRINTF(Cache, "Uni-coherence snoops a read that hit in itself" + ". Should satisfy the packet\n"); + return true; //Satisfy Reads if we can + } } return false; } -void +bool UniCoherence::propogateInvalidate(PacketPtr pkt, bool isTiming) { + //Make sure we don't snoop a write + //we are expecting writeInvalidates on the snoop port of a uni-coherent cache + assert(!(!pkt->isInvalidate() && pkt->isWrite())); + if (pkt->isInvalidate()) { +/* Temp Fix for now, forward all invalidates up as functional accesses */ if (isTiming) { // Forward to other caches - PacketPtr tmp = new Packet(pkt->req, Packet::InvalidateReq, -1); + Request* req = new Request(pkt->req->getPaddr(), pkt->getSize(), 0); + PacketPtr tmp = new Packet(req, Packet::InvalidateReq, -1); cshrs.allocate(tmp); cache->setSlaveRequest(Request_Coherence, curTick); if (cshrs.isFull()) @@ -102,5 +114,26 @@ UniCoherence::propogateInvalidate(PacketPtr pkt, bool isTiming) cache->cpuSidePort->sendAtomic(tmp); delete tmp; } +/**/ +/* PacketPtr tmp = new Packet(pkt->req, Packet::InvalidateReq, -1); + cache->cpuSidePort->sendFunctional(tmp); + delete tmp; +*/ + } + if (pkt->isRead()) { + /*For now we will see if someone above us has the data by + doing a functional access on reads. Fix this later */ + PacketPtr tmp = new Packet(pkt->req, Packet::ReadReq, -1); + tmp->allocate(); + cache->cpuSidePort->sendFunctional(tmp); + bool hit = (tmp->result == Packet::Success); + if (hit) { + memcpy(pkt->getPtr(), tmp->getPtr(), + pkt->getSize()); + DPRINTF(Cache, "Uni-coherence snoops a read that hit in L1\n"); + } + delete tmp; + return hit; } + return false; } diff --git a/src/mem/cache/coherence/uni_coherence.hh b/src/mem/cache/coherence/uni_coherence.hh index 44c752088..9a4aacdec 100644 --- a/src/mem/cache/coherence/uni_coherence.hh +++ b/src/mem/cache/coherence/uni_coherence.hh @@ -140,7 +140,7 @@ class UniCoherence bool hasProtocol() { return false; } - void propogateInvalidate(PacketPtr pkt, bool isTiming); + bool propogateInvalidate(PacketPtr pkt, bool isTiming); }; #endif //__UNI_COHERENCE_HH__ -- cgit v1.2.3