ruby: connect two controllers using only message buffers

This patch modifies ruby so that two controllers can be connected to each
other with only message buffers in between. Before this patch, all the
controllers had to be connected to the network  for them to communicate
with each other. With this patch, one can have protocols where a controller
is not connected to the network, but communicates with another controller
through a message buffer.

src/mem/ruby/slicc_interface/AbstractController.cc

@@ -79,3 +79,10 @@ AbstractController::profileMsgDelay(uint32_t virtualNetwork, Cycles delay)
     m_delayHistogram.add(delay);
     m_delayVCHistogram[virtualNetwork].add(delay);
 }
+
+void
+AbstractController::connectWithPeer(AbstractController *c)
+{
+    getQueuesFromPeer(c);
+    c->getQueuesFromPeer(this);
+}

src/mem/ruby/slicc_interface/AbstractController.hh

@@ -97,12 +97,25 @@ class AbstractController : public ClockedObject, public Consumer
     Histogram& getDelayVCHist(uint32_t index)
     { return m_delayVCHistogram[index]; }
 
+    MessageBuffer *getPeerQueue(uint32_t pid)
+    {
+        std::map<uint32_t, MessageBuffer *>::iterator it =
+                                        peerQueueMap.find(pid);
+        assert(it != peerQueueMap.end());
+        return (*it).second;
+    }
+
   protected:
     //! Profiles original cache requests including PUTs
     void profileRequest(const std::string &request);
     //! Profiles the delay associated with messages.
     void profileMsgDelay(uint32_t virtualNetwork, Cycles delay);
 
+    //! Function for connecting peer controllers
+    void connectWithPeer(AbstractController *);
+    virtual void getQueuesFromPeer(AbstractController *)
+    { fatal("getQueuesFromPeer() should be called only if implemented!"); }
+
   protected:
     int m_transitions_per_cycle;
     int m_buffer_size;
@@ -120,6 +133,9 @@ class AbstractController : public ClockedObject, public Consumer
     int m_cur_in_port_rank;
     int m_number_of_TBEs;
 
+    //! Map from physical network number to the Message Buffer.
+    std::map<uint32_t, MessageBuffer*> peerQueueMap;
+
     //! Counter for the number of cycles when the transitions carried out
     //! were equal to the maximum allowed
     uint64_t m_fully_busy_cycles;

src/mem/ruby/slicc_interface/Controller.py

@@ -42,4 +42,6 @@ class RubyController(ClockedObject):
     buffer_size = Param.Int(0, "max buffer size 0 means infinite")
     recycle_latency = Param.Cycles(10, "")
     number_of_TBEs = Param.Int(256, "")
-    ruby_system = Param.RubySystem("");
+    ruby_system = Param.RubySystem("")
+
+    peer = Param.RubyController(NULL, "")

src/mem/slicc/ast/ObjDeclAST.py

@@ -41,7 +41,8 @@ class ObjDeclAST(DeclAST):
     def generate(self):
         machineComponentSym = False
 
-        if "network" in self and "virtual_network" not in self:
+        if "network" in self and not ("virtual_network" in self or
+                                      "physical_network" in self) :
             self.error("Network queues require a 'virtual_network' attribute")
 
         type = self.type_ast.type

src/mem/slicc/symbols/StateMachine.py

@@ -239,9 +239,12 @@ class $py_ident(RubyController):
 ''')
 
         seen_types = set()
+        has_peer = False
         for var in self.objects:
             if var.type.ident not in seen_types and not var.type.isPrimitive:
                 code('#include "mem/protocol/${{var.type.c_ident}}.hh"')
+            if "network" in var and "physical_network" in var:
+                has_peer = True
             seen_types.add(var.type.ident)
 
         # for adding information to the protocol debug trace
@@ -331,6 +334,8 @@ static int m_num_controllers;
             if proto:
                 code('$proto')
 
+        if has_peer:
+            code('void getQueuesFromPeer(AbstractController *);')
         if self.EntryType != None:
             code('''
 
@@ -388,6 +393,7 @@ void unset_tbe(${{self.TBEType.c_ident}}*& m_tbe_ptr);
         code = self.symtab.codeFormatter()
         ident = self.ident
         c_ident = "%s_Controller" % self.ident
+        has_peer = False
 
         code('''
 /** \\file $c_ident.cc
@@ -514,8 +520,21 @@ m_dma_sequencer_ptr->setController(this);
                 code('''
 m_${{var.c_ident}}_ptr = new ${{var.type.c_ident}}();
 m_${{var.c_ident}}_ptr->setReceiver(this);
+''')
+            else:
+                if "network" in var and "physical_network" in var and \
+                   var["network"] == "To":
+                    has_peer = True
+                    code('''
+m_${{var.c_ident}}_ptr = new ${{var.type.c_ident}}();
+peerQueueMap[${{var["physical_network"]}}] = m_${{var.c_ident}}_ptr;
+m_${{var.c_ident}}_ptr->setSender(this);
 ''')
 
+        code('''
+if (p->peer != NULL)
+    connectWithPeer(p->peer);
+''')
         code.dedent()
         code('''
 }
@@ -549,10 +568,7 @@ $c_ident::init()
                         code('(*$vid) = ${{var["default"]}};')
                 else:
                     # Normal Object
-                    # added by SS
+                    if var.ident.find("mandatoryQueue") < 0:
-                    if "factory" in var:
-                        code('$vid = ${{var["factory"]}};')
-                    elif var.ident.find("mandatoryQueue") < 0:
                         th = var.get("template", "")
                         expr = "%s  = new %s%s" % (vid, vtype.c_ident, th)
                         args = ""
@@ -593,16 +609,17 @@ $c_ident::init()
                 # Network port object
                 network = var["network"]
                 ordered =  var["ordered"]
+
+                if "virtual_network" in var:
                     vnet = var["virtual_network"]
                     vnet_type = var["vnet_type"]
 
                     assert var.machine is not None
                     code('''
 $vid = m_net_ptr->get${network}NetQueue(m_version + base, $ordered, $vnet, "$vnet_type");
+assert($vid != NULL);
 ''')
 
-                code('assert($vid != NULL);')
-
                     # Set the end
                     if network == "To":
                         code('$vid->setSender(this);')
@@ -1007,6 +1024,26 @@ $c_ident::functionalWriteBuffers(PacketPtr& pkt)
 }
 ''')
 
+        # Check if this controller has a peer, if yes then write the
+        # function for connecting to the peer.
+        if has_peer:
+            code('''
+
+void
+$c_ident::getQueuesFromPeer(AbstractController *peer)
+{
+''')
+            for var in self.objects:
+                if "network" in var and "physical_network" in var and \
+                   var["network"] == "From":
+                    code('''
+m_${{var.c_ident}}_ptr = peer->getPeerQueue(${{var["physical_network"]}});
+assert(m_${{var.c_ident}}_ptr != NULL);
+m_${{var.c_ident}}_ptr->setReceiver(this);
+
+''')
+            code('}')
+
         code.write(path, "%s.cc" % c_ident)
 
     def printCWakeup(self, path, includes):