From 78de00091b8487ae5de0bff1537d63042de99f33 Mon Sep 17 00:00:00 2001 From: Kevin Lim Date: Fri, 23 Mar 2007 13:09:37 -0400 Subject: 3 memory system fixes: 1. Update packet's flags properly when a snoop happens 2. Don't allow accesses to read a block's data if the block has outstanding MSHRs. This avoids a RAW hazard in MP systems that the memory system was not detecting properly earlier (a write required a block to upgrade, and while the upgrade was outstanding, a read came along and read old data). 3. Update MSHR's request upon a response being handled. If the MSHR has more targets than it can respond to in one cycle, then its request must be properly updated to the new head of the targets list. src/mem/bus.cc: Update packet's flags properly upon snoop. src/mem/cache/cache_impl.hh: Be sure to not allow accesses to a block with outstanding MSHRs. src/mem/cache/miss/miss_queue.cc: Update MSHR's request upon a response being handled. --HG-- extra : convert_revision : 76a9abc610ca3f1904f075ad21637148a41982d6 --- src/mem/bus.cc | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'src/mem/bus.cc') diff --git a/src/mem/bus.cc b/src/mem/bus.cc index bd721dd68..401dc0186 100644 --- a/src/mem/bus.cc +++ b/src/mem/bus.cc @@ -159,8 +159,12 @@ Bus::recvTiming(PacketPtr pkt) } short dest = pkt->getDest(); + + // Make sure to clear the snoop commit flag so it doesn't think an + // access has been handled twice. if (dest == Packet::Broadcast) { port = findPort(pkt->getAddr(), pkt->getSrc()); + pkt->flags &= ~SNOOP_COMMIT; if (timingSnoop(pkt, port ? port : interfaces[pkt->getSrc()])) { bool success; -- cgit v1.2.3