diff options
Diffstat (limited to 'src/mem/cache/cache_impl.hh')
| -rw-r--r-- | src/mem/cache/cache_impl.hh | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/src/mem/cache/cache_impl.hh b/src/mem/cache/cache_impl.hh index 6db40b609..2ead54ba6 100644 --- a/src/mem/cache/cache_impl.hh +++ b/src/mem/cache/cache_impl.hh @@ -371,6 +371,17 @@ Cache<TagStore>::timingAccess(PacketPtr pkt) DPRINTF(Cache, "mem inhibited on 0x%x: not responding\n", pkt->getAddr()); assert(!pkt->req->isUncacheable()); + // Special tweak for multilevel coherence: snoop downward here + // on invalidates since there may be other caches below here + // that have shared copies. Not necessary if we know that + // supplier had exclusive copy to begin with. + if (pkt->needsExclusive() && !pkt->isSupplyExclusive()) { + Packet *snoopPkt = new Packet(pkt, true); // clear flags + snoopPkt->setExpressSnoop(); + snoopPkt->assertMemInhibit(); + memSidePort->sendTiming(snoopPkt); + // main memory will delete snoopPkt + } return true; } @@ -966,6 +977,7 @@ Cache<TagStore>::handleSnoop(PacketPtr pkt, BlkType *blk, // we respond in atomic mode), so just figure out what to do now // and then do it later bool supply = blk->isDirty() && pkt->isRead() && !upperSupply; + bool have_exclusive = blk->isWritable(); bool invalidate = pkt->isInvalidate(); if (pkt->isRead() && !pkt->isInvalidate()) { @@ -985,6 +997,9 @@ Cache<TagStore>::handleSnoop(PacketPtr pkt, BlkType *blk, if (supply) { assert(!pkt->memInhibitAsserted()); pkt->assertMemInhibit(); + if (have_exclusive) { + pkt->setSupplyExclusive(); + } if (is_timing) { doTimingSupplyResponse(pkt, blk->data, is_deferred); } else { |