diff options
Diffstat (limited to 'src/mem/cache/mshr.cc')
| -rw-r--r-- | src/mem/cache/mshr.cc | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/src/mem/cache/mshr.cc b/src/mem/cache/mshr.cc index c59fa0020..78900ed4e 100644 --- a/src/mem/cache/mshr.cc +++ b/src/mem/cache/mshr.cc @@ -365,17 +365,28 @@ MSHR::handleSnoop(PacketPtr pkt, Counter _order) // Clear flags and also allocate new data as the original // packet data storage may have been deleted by the time we // get to send this packet. - PacketPtr cp_pkt = new Packet(pkt, true, true); - targets.add(cp_pkt, curTick(), _order, Target::FromSnoop, - downstreamPending && targets.needsExclusive); + PacketPtr cp_pkt = nullptr; if (isPendingDirty()) { + // Case 1: The new packet will need to get the response from the + // MSHR already queued up here + cp_pkt = new Packet(pkt, true, true); pkt->assertMemInhibit(); // in the case of an uncacheable request there is no need // to set the exclusive flag, but since the recipient does // not care there is no harm in doing so pkt->setSupplyExclusive(); + } else { + // Case 2: We only need to buffer the packet for information + // purposes; the original request can proceed without waiting + // => Create a copy of the request, as that may get deallocated as + // well + cp_pkt = new Packet(new Request(*pkt->req), pkt->cmd); + DPRINTF(Cache, "Copying packet %p -> %p and request %p -> %p\n", + pkt, cp_pkt, pkt->req, cp_pkt->req); } + targets.add(cp_pkt, curTick(), _order, Target::FromSnoop, + downstreamPending && targets.needsExclusive); if (pkt->needsExclusive()) { // This transaction will take away our pending copy |