From 2f93db6f95b02d2bedf9571330a3185ac3fa7fa9 Mon Sep 17 00:00:00 2001
From: Steve Reinhardt <stever@gmail.com>
Date: Sun, 29 Jul 2007 20:17:03 -0700
Subject: [PATCH] memory system: fix functional access bug. Make sure not to
 keep processing functional accesses after they've been responded to. Also use
 checkFunctional() return value instead of checking packet command field where
 possible, mostly just for consistency.

--HG--
extra : convert_revision : 29fc76bc18731bd93a4ed05a281297827028ef75
---
 src/mem/cache/base_cache.cc |  4 ++--
 src/mem/cache/cache_impl.hh |  8 ++++----
 src/mem/physical.cc         | 12 ++++++------
 src/mem/tport.cc            | 13 +++++++------
 src/mem/tport.hh            |  2 +-
 5 files changed, 20 insertions(+), 19 deletions(-)

diff --git a/src/mem/cache/base_cache.cc b/src/mem/cache/base_cache.cc
index ec9e1cf9b..b44468486 100644
--- a/src/mem/cache/base_cache.cc
+++ b/src/mem/cache/base_cache.cc
@@ -81,9 +81,9 @@ BaseCache::CachePort::deviceBlockSize()
 void
 BaseCache::CachePort::checkAndSendFunctional(PacketPtr pkt)
 {
-    checkFunctional(pkt);
-    if (!pkt->isResponse())
+    if (!checkFunctional(pkt)) {
         sendFunctional(pkt);
+    }
 }
 
 
diff --git a/src/mem/cache/cache_impl.hh b/src/mem/cache/cache_impl.hh
index c1b01d676..d144266ed 100644
--- a/src/mem/cache/cache_impl.hh
+++ b/src/mem/cache/cache_impl.hh
@@ -1253,9 +1253,9 @@ template<class TagStore>
 void
 Cache<TagStore>::CpuSidePort::recvFunctional(PacketPtr pkt)
 {
-    checkFunctional(pkt);
-    if (!pkt->isResponse())
+    if (!checkFunctional(pkt)) {
         myCache()->functionalAccess(pkt, cache->memSidePort);
+    }
 }
 
 
@@ -1327,9 +1327,9 @@ template<class TagStore>
 void
 Cache<TagStore>::MemSidePort::recvFunctional(PacketPtr pkt)
 {
-    checkFunctional(pkt);
-    if (!pkt->isResponse())
+    if (!checkFunctional(pkt)) {
         myCache()->functionalAccess(pkt, cache->cpuSidePort);
+    }
 }
 
 
diff --git a/src/mem/physical.cc b/src/mem/physical.cc
index b96fb8a56..2f358daf2 100644
--- a/src/mem/physical.cc
+++ b/src/mem/physical.cc
@@ -400,12 +400,12 @@ PhysicalMemory::MemoryPort::recvAtomic(PacketPtr pkt)
 void
 PhysicalMemory::MemoryPort::recvFunctional(PacketPtr pkt)
 {
-    checkFunctional(pkt);
-
-    // Default implementation of SimpleTimingPort::recvFunctional()
-    // calls recvAtomic() and throws away the latency; we can save a
-    // little here by just not calculating the latency.
-    memory->doFunctionalAccess(pkt);
+    if (!checkFunctional(pkt)) {
+        // Default implementation of SimpleTimingPort::recvFunctional()
+        // calls recvAtomic() and throws away the latency; we can save a
+        // little here by just not calculating the latency.
+        memory->doFunctionalAccess(pkt);
+    }
 }
 
 unsigned int
diff --git a/src/mem/tport.cc b/src/mem/tport.cc
index e4b8d70e9..b1a6a4813 100644
--- a/src/mem/tport.cc
+++ b/src/mem/tport.cc
@@ -30,7 +30,7 @@
 
 #include "mem/tport.hh"
 
-void
+bool
 SimpleTimingPort::checkFunctional(PacketPtr pkt)
 {
     DeferredPacketIterator i = transmitList.begin();
@@ -41,19 +41,20 @@ SimpleTimingPort::checkFunctional(PacketPtr pkt)
         // If the target contains data, and it overlaps the
         // probed request, need to update data
         if (pkt->checkFunctional(target)) {
-            return;
+            return true;
         }
     }
+
+    return false;
 }
 
 void
 SimpleTimingPort::recvFunctional(PacketPtr pkt)
 {
-    checkFunctional(pkt);
-
-    // Just do an atomic access and throw away the returned latency
-    if (!pkt->isResponse())
+    if (!checkFunctional(pkt)) {
+        // Just do an atomic access and throw away the returned latency
         recvAtomic(pkt);
+    }
 }
 
 bool
diff --git a/src/mem/tport.hh b/src/mem/tport.hh
index bc9da6c44..d0f1be425 100644
--- a/src/mem/tport.hh
+++ b/src/mem/tport.hh
@@ -99,7 +99,7 @@ class SimpleTimingPort : public Port
 
     /** Check the list of buffered packets against the supplied
      * functional request. */
-    void checkFunctional(PacketPtr funcPkt);
+    bool checkFunctional(PacketPtr funcPkt);
 
     /** Check whether we have a packet ready to go on the transmit list. */
     bool deferredPacketReady()