MEM: Simplify ports by removing EventManager

This patch removes the inheritance of EventManager from the ports and
moves all responsibility for event queues to the owner. Eventually the
event manager should be the interface block, which could either be the
structural owner or a subblock like a LSQ in the O3 CPU for example.

src/cpu/simple/timing.cc

@@ -862,7 +862,7 @@ TimingSimpleCPU::DcachePort::recvTiming(PacketPtr pkt)
                 // faster than a CPU we could get two responses before
                 // next_tick expires
                 if (!retryEvent.scheduled())
-                    schedule(retryEvent, next_tick);
+                    cpu->schedule(retryEvent, next_tick);
                 return false;
             }
         }

src/dev/io_device.cc

@@ -136,7 +136,7 @@ DmaPort::recvTiming(PacketPtr pkt)
         else if (backoffTime < maxBackoffDelay)
             backoffTime <<= 1;
 
-        reschedule(backoffEvent, curTick() + backoffTime, true);
+        device->reschedule(backoffEvent, curTick() + backoffTime, true);
 
         DPRINTF(DMA, "Backoff time set to %d ticks\n", backoffTime);
 
@@ -164,7 +164,8 @@ DmaPort::recvTiming(PacketPtr pkt)
         if (state->totBytes == state->numBytes) {
             if (state->completionEvent) {
                 if (state->delay)
-                    schedule(state->completionEvent, curTick() + state->delay);
+                    device->schedule(state->completionEvent,
+                                     curTick() + state->delay);
                 else
                     state->completionEvent->process();
             }
@@ -234,7 +235,7 @@ DmaPort::recvRetry()
     if (transmitList.size() && backoffTime && !inRetry) {
         DPRINTF(DMA, "Scheduling backoff for %d\n", curTick()+backoffTime);
         if (!backoffEvent.scheduled())
-            schedule(backoffEvent, backoffTime + curTick());
+            device->schedule(backoffEvent, backoffTime + curTick());
     }
     DPRINTF(DMA, "TransmitList: %d, backoffTime: %d inRetry: %d es: %d\n",
             transmitList.size(), backoffTime, inRetry,
@@ -320,7 +321,7 @@ DmaPort::sendDma()
                 !backoffEvent.scheduled()) {
             DPRINTF(DMA, "-- Scheduling backoff timer for %d\n",
                     backoffTime+curTick());
-            schedule(backoffEvent, backoffTime + curTick());
+            device->schedule(backoffEvent, backoffTime + curTick());
         }
     } else if (state == Enums::atomic) {
         transmitList.pop_front();
@@ -342,7 +343,8 @@ DmaPort::sendDma()
         if (state->totBytes == state->numBytes) {
             if (state->completionEvent) {
                 assert(!state->completionEvent->scheduled());
-                schedule(state->completionEvent, curTick() + lat + state->delay);
+                device->schedule(state->completionEvent,
+                                 curTick() + lat + state->delay);
             }
             delete state;
             delete pkt->req;

src/mem/bridge.cc

@@ -165,7 +165,7 @@ Bridge::BridgePort::nackRequest(PacketPtr pkt)
     // nothing on the list, add it and we're done
     if (sendQueue.empty()) {
         assert(!sendEvent.scheduled());
-        schedule(sendEvent, readyTime);
+        bridge->schedule(sendEvent, readyTime);
         sendQueue.push_back(buf);
         return;
     }
@@ -187,7 +187,7 @@ Bridge::BridgePort::nackRequest(PacketPtr pkt)
     while (i != end && !done) {
         if (readyTime < (*i)->ready) {
             if (i == begin)
-                reschedule(sendEvent, readyTime);
+                bridge->reschedule(sendEvent, readyTime);
             sendQueue.insert(i,buf);
             done = true;
         }
@@ -230,7 +230,7 @@ Bridge::BridgePort::queueForSendTiming(PacketPtr pkt)
     // should already be an event scheduled for sending the head
     // packet.
     if (sendQueue.empty()) {
-        schedule(sendEvent, readyTime);
+        bridge->schedule(sendEvent, readyTime);
     }
     sendQueue.push_back(buf);
 }
@@ -284,7 +284,7 @@ Bridge::BridgePort::trySend()
         if (!sendQueue.empty()) {
             buf = sendQueue.front();
             DPRINTF(BusBridge, "Scheduling next send\n");
-            schedule(sendEvent, std::max(buf->ready, curTick() + 1));
+            bridge->schedule(sendEvent, std::max(buf->ready, curTick() + 1));
         }
     } else {
         DPRINTF(BusBridge, "  unsuccessful\n");
@@ -305,7 +305,7 @@ Bridge::BridgePort::recvRetry()
     if (nextReady <= curTick())
         trySend();
     else
-        schedule(sendEvent, nextReady);
+        bridge->schedule(sendEvent, nextReady);
 }
 
 /** Function called by the port when the bus is receiving a Atomic

src/mem/cache/base.cc

@@ -126,7 +126,7 @@ BaseCache::CachePort::clearBlocked()
         mustSendRetry = false;
         SendRetryEvent *ev = new SendRetryEvent(this, true);
         // @TODO: need to find a better time (next bus cycle?)
-        schedule(ev, curTick() + 1);
+        cache->schedule(ev, curTick() + 1);
     }
 }
 

src/mem/cache/cache_impl.hh

@@ -1729,7 +1729,7 @@ Cache<TagStore>::MemSidePort::sendPacket()
         // @TODO: need to facotr in prefetch requests here somehow
         if (nextReady != MaxTick) {
             DPRINTF(CachePort, "more packets to send @ %d\n", nextReady);
-            schedule(sendEvent, std::max(nextReady, curTick() + 1));
+            cache->schedule(sendEvent, std::max(nextReady, curTick() + 1));
         } else {
             // no more to send right now: if we're draining, we may be done
             if (drainEvent && !sendEvent->scheduled()) {

src/mem/port.cc

@@ -93,8 +93,7 @@ class DefaultPeerPort : public Port
 DefaultPeerPort defaultPeerPort;
 
 Port::Port(const std::string &_name, MemObject *_owner)
-    : EventManager(_owner), portName(_name), peer(&defaultPeerPort),
-      owner(_owner)
+    : portName(_name), peer(&defaultPeerPort), owner(_owner)
 {
 }
 
@@ -113,7 +112,6 @@ Port::setPeer(Port *port)
 void
 Port::setOwner(MemObject *_owner)
 {
-    eventq = _owner->queue();
     owner = _owner;
 }
 

src/mem/port.hh

@@ -47,7 +47,6 @@
 #include "base/types.hh"
 #include "mem/packet.hh"
 #include "mem/request.hh"
-#include "sim/eventq.hh"
 
 /** This typedef is used to clean up the parameter list of
  * getDeviceAddressRanges() and getPeerAddressRanges().  It's declared
@@ -59,7 +58,6 @@
 typedef std::list<Range<Addr> > AddrRangeList;
 typedef std::list<Range<Addr> >::iterator AddrRangeIter;
 
-class EventQueue;
 class MemObject;
 
 /**
@@ -73,7 +71,7 @@ class MemObject;
  * Send accessor functions are being called from the device the port is
  * associated with, and it will call the peer recv. accessor function.
  */
-class Port : public EventManager
+class Port
 {
   protected:
     /** Descriptive name (for DPRINTF output) */

src/mem/tport.cc

@@ -29,12 +29,13 @@
  */
 
 #include "debug/Bus.hh"
+#include "mem/mem_object.hh"
 #include "mem/tport.hh"
 
 using namespace std;
 
 SimpleTimingPort::SimpleTimingPort(string pname, MemObject *_owner)
-    : Port(pname, _owner), sendEvent(0), drainEvent(NULL),
+    : Port(pname, _owner), sendEvent(NULL), drainEvent(NULL),
       waitingOnRetry(false)
 {
     sendEvent =  new EventWrapper<SimpleTimingPort,
@@ -104,6 +105,20 @@ SimpleTimingPort::recvTiming(PacketPtr pkt)
     return true;
 }
 
+void
+SimpleTimingPort::schedSendEvent(Tick when)
+{
+    if (waitingOnRetry) {
+        assert(!sendEvent->scheduled());
+        return;
+    }
+
+    if (!sendEvent->scheduled()) {
+        owner->schedule(sendEvent, when);
+    } else if (sendEvent->when() > when) {
+        owner->reschedule(sendEvent, when);
+    }
+}
 
 void
 SimpleTimingPort::schedSendTiming(PacketPtr pkt, Tick when)
@@ -153,7 +168,7 @@ SimpleTimingPort::sendDeferredPacket()
     if (success) {
         if (!transmitList.empty() && !sendEvent->scheduled()) {
             Tick time = transmitList.front().tick;
-            schedule(sendEvent, time <= curTick() ? curTick()+1 : time);
+            owner->schedule(sendEvent, time <= curTick() ? curTick()+1 : time);
         }
 
         if (transmitList.empty() && drainEvent && !sendEvent->scheduled()) {

src/mem/tport.hh

@@ -106,21 +106,14 @@ class SimpleTimingPort : public Port
     Tick deferredPacketReadyTime()
     { return transmitList.empty() ? MaxTick : transmitList.front().tick; }
 
-    void
-    schedSendEvent(Tick when)
-    {
-        if (waitingOnRetry) {
-            assert(!sendEvent->scheduled());
-            return;
-        }
-
-        if (!sendEvent->scheduled()) {
-            schedule(sendEvent, when);
-        } else if (sendEvent->when() > when) {
-            reschedule(sendEvent, when);
-        }
-    }
-
+    /**
+     * Schedule a send even if not already waiting for a retry. If the
+     * requested time is before an already scheduled send event it
+     * will be rescheduled.
+     *
+     * @param when
+     */
+    void schedSendEvent(Tick when);
 
     /** Schedule a sendTiming() event to be called in the future.
      * @param pkt packet to send