MEM: Split SimpleTimingPort into PacketQueue and ports

This patch decouples the queueing and the port interactions to
simplify the introduction of the master and slave ports. By separating
the queueing functionality from the port itself, it becomes much
easier to distinguish between master and slave ports, and still retain
the queueing ability for both (without code duplication).

As part of the split into a PacketQueue and a port, there is now also
a hierarchy of two port classes, QueuedPort and SimpleTimingPort. The
QueuedPort is useful for ports that want to leave the packet
transmission of outgoing packets to the queue and is used by both
master and slave ports. The SimpleTimingPort inherits from the
QueuedPort and adds the implemention of recvTiming and recvFunctional
through recvAtomic.

The PioPort and MessagePort are cleaned up as part of the changes.

--HG--
rename : src/mem/tport.cc => src/mem/packet_queue.cc
rename : src/mem/tport.hh => src/mem/packet_queue.hh

1 files changed, 7 insertions, 6 deletions

diff --git a/src/mem/cache/cache_impl.hh b/src/mem/cache/cache_impl.hh
index f6efc3fb8..2463071de 100644
--- a/src/mem/cache/cache_impl.hh
+++ b/src/mem/cache/cache_impl.hh
@@ -1646,7 +1646,7 @@ Cache<TagStore>::MemSidePort::recvFunctional(PacketPtr pkt)
 
 template<class TagStore>
 void
-Cache<TagStore>::MemSidePort::sendDeferredPacket()
+Cache<TagStore>::MemSidePacketQueue::sendDeferredPacket()
 {
     // if we have a response packet waiting we have to start with that
     if (deferredPacketReady()) {
@@ -1654,7 +1654,7 @@ Cache<TagStore>::MemSidePort::sendDeferredPacket()
         trySendTiming();
     } else {
         // check for request packets (requests & writebacks)
-        PacketPtr pkt = cache->getTimingPacket();
+        PacketPtr pkt = cache.getTimingPacket();
         if (pkt == NULL) {
             // can happen if e.g. we attempt a writeback and fail, but
             // before the retry, the writeback is eliminated because
@@ -1663,7 +1663,7 @@ Cache<TagStore>::MemSidePort::sendDeferredPacket()
         } else {
             MSHR *mshr = dynamic_cast<MSHR*>(pkt->senderState);
 
-            waitingOnRetry = !sendTiming(pkt);
+            waitingOnRetry = !port.sendTiming(pkt);
 
             if (waitingOnRetry) {
                 DPRINTF(CachePort, "now waiting on a retry\n");
@@ -1679,7 +1679,7 @@ Cache<TagStore>::MemSidePort::sendDeferredPacket()
                 // care about this packet and might override it before
                 // it gets retried
             } else {
-                cache->markInService(mshr, pkt);
+                cache.markInService(mshr, pkt);
             }
         }
     }
@@ -1688,7 +1688,7 @@ Cache<TagStore>::MemSidePort::sendDeferredPacket()
     // next send, not only looking at the response transmit list, but
     // also considering when the next MSHR is ready
     if (!waitingOnRetry) {
-        scheduleSend(cache->nextMSHRReadyTime());
+        scheduleSend(cache.nextMSHRReadyTime());
     }
 }
 
@@ -1696,6 +1696,7 @@ template<class TagStore>
 Cache<TagStore>::
 MemSidePort::MemSidePort(const std::string &_name, Cache<TagStore> *_cache,
                          const std::string &_label)
-    : BaseCache::CacheMasterPort(_name, _cache, _label), cache(_cache)
+    : BaseCache::CacheMasterPort(_name, _cache, _queue),
+      _queue(*_cache, *this, _label), cache(_cache)
 {
 }