Fixes to get prefetching working again.

Apparently we broke it with the cache rewrite and never noticed.
Thanks to Bao Yungang <baoyungang@gmail.com> for a significant part
of these changes (and for inspiring me to work on the rest).
Some other overdue cleanup on the prefetch code too.

1 files changed, 12 insertions, 7 deletions

diff --git a/src/mem/cache/mshr.hh b/src/mem/cache/mshr.hh
index 2ff1c2489..bed7012b0 100644
--- a/src/mem/cache/mshr.hh
+++ b/src/mem/cache/mshr.hh
@@ -55,20 +55,25 @@ class MSHR : public Packet::SenderState, public Printable
 
     class Target {
       public:
+
+        enum Source {
+            FromCPU,
+            FromSnoop,
+            FromPrefetcher
+        };
+
         Tick recvTime;  //!< Time when request was received (for stats)
         Tick readyTime; //!< Time when request is ready to be serviced
         Counter order;  //!< Global order (for memory consistency mgmt)
         PacketPtr pkt;  //!< Pending request packet.
-        bool cpuSide;   //!< Did request come from cpu side or mem side?
+        Source source;  //!< Did request come from cpu, memory, or prefetcher?
         bool markedPending; //!< Did we mark upstream MSHR
                             //!<  as downstreamPending?
 
-        bool isCpuSide() const { return cpuSide; }
-
         Target(PacketPtr _pkt, Tick _readyTime, Counter _order,
-               bool _cpuSide, bool _markedPending)
+               Source _source, bool _markedPending)
             : recvTime(curTick), readyTime(_readyTime), order(_order),
-              pkt(_pkt), cpuSide(_cpuSide), markedPending(_markedPending)
+              pkt(_pkt), source(_source), markedPending(_markedPending)
         {}
     };
 
@@ -85,7 +90,7 @@ class MSHR : public Packet::SenderState, public Printable
         void resetFlags() { needsExclusive = hasUpgrade = false; }
         bool isReset()    { return !needsExclusive && !hasUpgrade; }
         void add(PacketPtr pkt, Tick readyTime, Counter order,
-                 bool cpuSide, bool markPending);
+                 Target::Source source, bool markPending);
         void replaceUpgrades();
         void clearDownstreamPending();
         bool checkFunctional(PacketPtr pkt);
@@ -238,7 +243,7 @@ public:
         if (getNumTargets() != 1)
             return false;
         Target *tgt = getTarget();
-        return tgt->isCpuSide() && !tgt->pkt->needsResponse();
+        return tgt->source == Target::FromCPU && !tgt->pkt->needsResponse();
     }
 
     bool promoteDeferredTargets();