mem: Explicitly check MSHR snoops for cases not dealt with

Add a sanity check to make it explicit that we currently do not allow
an I/O coherent agent to directly issue writes into the coherent part
of the memory system (it has to go via a cache, and get transformed
into a read ex, upgrade or invalidation).
This commit is contained in:
Andreas Hansson 2015-12-28 11:14:18 -05:00
parent f6525ff221
commit f5c4a45889

View file

@ -323,6 +323,15 @@ MSHR::handleSnoop(PacketPtr pkt, Counter _order)
{ {
DPRINTF(Cache, "%s for %s addr %#llx size %d\n", __func__, DPRINTF(Cache, "%s for %s addr %#llx size %d\n", __func__,
pkt->cmdString(), pkt->getAddr(), pkt->getSize()); pkt->cmdString(), pkt->getAddr(), pkt->getSize());
// when we snoop packets the needsExclusive and isInvalidate flags
// should always be the same, however, this assumes that we never
// snoop writes as they are currently not marked as invalidations
panic_if(pkt->needsExclusive() != pkt->isInvalidate(),
"%s got snoop %s to addr %#llx where needsExclusive, "
"does not match isInvalidate", name(), pkt->cmdString(),
pkt->getAddr());
if (!inService || (pkt->isExpressSnoop() && downstreamPending)) { if (!inService || (pkt->isExpressSnoop() && downstreamPending)) {
// Request has not been issued yet, or it's been issued // Request has not been issued yet, or it's been issued
// locally but is buffered unissued at some downstream cache // locally but is buffered unissued at some downstream cache