ruby: more flexible ruby tester support

This patch allows the ruby random tester to use ruby ports that may only
support instr or data requests.  This patch is similar to a previous changeset
(8932:1b2c17565ac8) that was unfortunately broken by subsequent changesets.
This current patch implements the support in a more straight-forward way.
Since retries are now tested when running the ruby random tester, this patch
splits up the retry and drain check behavior so that RubyPort children, such
as the GPUCoalescer, can perform those operations correctly without having to
duplicate code.  Finally, the patch also includes better DPRINTFs for
debugging the tester.

4 files changed, 53 insertions, 26 deletions

diff --git a/src/mem/ruby/system/RubyPort.cc b/src/mem/ruby/system/RubyPort.cc
index b2fb8d72d..95a83873c 100644
--- a/src/mem/ruby/system/RubyPort.cc
+++ b/src/mem/ruby/system/RubyPort.cc
@@ -11,7 +11,7 @@
  * unmodified and in its entirety in all distributions of the software,
  * modified or unmodified, in source code or in binary form.
  *
- * Copyright (c) 2009 Advanced Micro Devices, Inc.
+ * Copyright (c) 2009-2013 Advanced Micro Devices, Inc.
  * Copyright (c) 2011 Mark D. Hill and David A. Wood
  * All rights reserved.
  *
@@ -58,7 +58,8 @@ RubyPort::RubyPort(const Params *p)
       pioSlavePort(csprintf("%s.pio-slave-port", name()), this),
       memMasterPort(csprintf("%s.mem-master-port", name()), this),
       memSlavePort(csprintf("%s-mem-slave-port", name()), this,
-                   p->ruby_system->getAccessBackingStore(), -1),
+                   p->ruby_system->getAccessBackingStore(), -1,
+                   p->no_retry_on_stall),
       gotAddrRanges(p->port_master_connection_count)
 {
     assert(m_version != -1);
@@ -66,7 +67,8 @@ RubyPort::RubyPort(const Params *p)
     // create the slave ports based on the number of connected ports
     for (size_t i = 0; i < p->port_slave_connection_count; ++i) {
         slave_ports.push_back(new MemSlavePort(csprintf("%s.slave%d", name(),
-            i), this, p->ruby_system->getAccessBackingStore(), i));
+            i), this, p->ruby_system->getAccessBackingStore(),
+            i, p->no_retry_on_stall));
     }
 
     // create the master ports based on the number of connected ports
@@ -156,9 +158,11 @@ RubyPort::MemMasterPort::MemMasterPort(const std::string &_name,
 }
 
 RubyPort::MemSlavePort::MemSlavePort(const std::string &_name, RubyPort *_port,
-                                     bool _access_backing_store, PortID id)
+                                     bool _access_backing_store, PortID id,
+                                     bool _no_retry_on_stall)
     : QueuedSlavePort(_name, _port, queue, id), queue(*_port, *this),
-      access_backing_store(_access_backing_store)
+      access_backing_store(_access_backing_store),
+      no_retry_on_stall(_no_retry_on_stall)
 {
     DPRINTF(RubyPort, "Created slave memport on ruby sequencer %s\n", _name);
 }
@@ -267,21 +271,31 @@ RubyPort::MemSlavePort::recvTimingReq(PacketPtr pkt)
         return true;
     }
 
-    //
-    // Unless one is using the ruby tester, record the stalled M5 port for
-    // later retry when the sequencer becomes free.
-    //
-    if (!ruby_port->m_usingRubyTester) {
-        ruby_port->addToRetryList(this);
-    }
 
     DPRINTF(RubyPort, "Request for address %#x did not issued because %s\n",
             pkt->getAddr(), RequestStatus_to_string(requestStatus));
 
+    addToRetryList();
+
     return false;
 }
 
 void
+RubyPort::MemSlavePort::addToRetryList()
+{
+    RubyPort *ruby_port = static_cast<RubyPort *>(&owner);
+
+    //
+    // Unless the requestor do not want retries (e.g., the Ruby tester),
+    // record the stalled M5 port for later retry when the sequencer
+    // becomes free.
+    //
+    if (!no_retry_on_stall && !ruby_port->onRetryList(this)) {
+        ruby_port->addToRetryList(this);
+    }
+}
+
+void
 RubyPort::MemSlavePort::recvFunctional(PacketPtr pkt)
 {
     DPRINTF(RubyPort, "Functional access for address: %#x\n", pkt->getAddr());
@@ -356,31 +370,33 @@ RubyPort::ruby_hit_callback(PacketPtr pkt)
 
     port->hitCallback(pkt);
 
+    trySendRetries();
+}
+
+void
+RubyPort::trySendRetries()
+{
     //
     // If we had to stall the MemSlavePorts, wake them up because the sequencer
     // likely has free resources now.
     //
     if (!retryList.empty()) {
-        //
-        // Record the current list of ports to retry on a temporary list before
-        // calling sendRetry on those ports.  sendRetry will cause an
-        // immediate retry, which may result in the ports being put back on the
-        // list. Therefore we want to clear the retryList before calling
-        // sendRetry.
-        //
+        // Record the current list of ports to retry on a temporary list
+        // before calling sendRetryReq on those ports. sendRetryReq will cause
+        // an immediate retry, which may result in the ports being put back on
+        // the list. Therefore we want to clear the retryList before calling
+        // sendRetryReq.
         std::vector<MemSlavePort *> curRetryList(retryList);
 
         retryList.clear();
 
         for (auto i = curRetryList.begin(); i != curRetryList.end(); ++i) {
             DPRINTF(RubyPort,
-                    "Sequencer may now be free.  SendRetry to port %s\n",
+                    "Sequencer may now be free. SendRetry to port %s\n",
                     (*i)->name());
             (*i)->sendRetryReq();
         }
     }
-
-    testDrainComplete();
 }
 
 void
diff --git a/src/mem/ruby/system/RubyPort.hh b/src/mem/ruby/system/RubyPort.hh
index 58d2558dd..07e0fde5a 100644
--- a/src/mem/ruby/system/RubyPort.hh
+++ b/src/mem/ruby/system/RubyPort.hh
@@ -11,7 +11,7 @@
  * unmodified and in its entirety in all distributions of the software,
  * modified or unmodified, in source code or in binary form.
  *
- * Copyright (c) 2009 Advanced Micro Devices, Inc.
+ * Copyright (c) 2009-2013 Advanced Micro Devices, Inc.
  * Copyright (c) 2011 Mark D. Hill and David A. Wood
  * All rights reserved.
  *
@@ -76,10 +76,12 @@ class RubyPort : public MemObject
       private:
         RespPacketQueue queue;
         bool access_backing_store;
+        bool no_retry_on_stall;
 
       public:
         MemSlavePort(const std::string &_name, RubyPort *_port,
-                     bool _access_backing_store, PortID id);
+                     bool _access_backing_store,
+                     PortID id, bool _no_retry_on_stall);
         void hitCallback(PacketPtr pkt);
         void evictionCallback(Addr address);
 
@@ -94,6 +96,8 @@ class RubyPort : public MemObject
         AddrRangeList getAddrRanges() const
         { AddrRangeList ranges; return ranges; }
 
+        void addToRetryList();
+
       private:
         bool isPhysMemAddress(Addr addr) const;
     };
@@ -164,6 +168,7 @@ class RubyPort : public MemObject
     DrainState drain() override;
 
   protected:
+    void trySendRetries();
     void ruby_hit_callback(PacketPtr pkt);
     void testDrainComplete();
     void ruby_eviction_callback(Addr address);
@@ -186,10 +191,14 @@ class RubyPort : public MemObject
     System* system;
 
   private:
+    bool onRetryList(MemSlavePort * port)
+    {
+        return (std::find(retryList.begin(), retryList.end(), port) !=
+                retryList.end());
+    }
     void addToRetryList(MemSlavePort * port)
     {
-        if (std::find(retryList.begin(), retryList.end(), port) !=
-               retryList.end()) return;
+        if (onRetryList(port)) return;
         retryList.push_back(port);
     }
 
diff --git a/src/mem/ruby/system/Sequencer.cc b/src/mem/ruby/system/Sequencer.cc
index 26db6b6f8..50418c700 100644
--- a/src/mem/ruby/system/Sequencer.cc
+++ b/src/mem/ruby/system/Sequencer.cc
@@ -491,6 +491,7 @@ Sequencer::hitCallback(SequencerRequest* srequest, DataBlock& data,
         rs->m_cache_recorder->enqueueNextFlushRequest();
     } else {
         ruby_hit_callback(pkt);
+        testDrainComplete();
     }
 }
 
diff --git a/src/mem/ruby/system/Sequencer.py b/src/mem/ruby/system/Sequencer.py
index 7494986e9..7c90eb29c 100644
--- a/src/mem/ruby/system/Sequencer.py
+++ b/src/mem/ruby/system/Sequencer.py
@@ -45,6 +45,7 @@ class RubyPort(MemObject):
     mem_slave_port = SlavePort("Ruby memory port")
 
     using_ruby_tester = Param.Bool(False, "")
+    no_retry_on_stall = Param.Bool(False, "")
     ruby_system = Param.RubySystem(Parent.any, "")
     system = Param.System(Parent.any, "system object")
     support_data_reqs = Param.Bool(True, "data cache requests supported")