ruby: changes how Topologies are created

Instead of just passing a list of controllers to the makeTopology function
in src/mem/ruby/network/topologies/<Topo>.py we pass in a function pointer
which knows how to make the topology, possibly with some extra state set
in the configs/ruby/<protocol>.py file. Thus, we can move all of the files
from network/topologies to configs/topologies. A new class BaseTopology
is added which all topologies in configs/topologies must inheirit from and
follow its API.

--HG--
rename : src/mem/ruby/network/topologies/Crossbar.py => configs/topologies/Crossbar.py
rename : src/mem/ruby/network/topologies/Mesh.py => configs/topologies/Mesh.py
rename : src/mem/ruby/network/topologies/MeshDirCorners.py => configs/topologies/MeshDirCorners.py
rename : src/mem/ruby/network/topologies/Pt2Pt.py => configs/topologies/Pt2Pt.py
rename : src/mem/ruby/network/topologies/Torus.py => configs/topologies/Torus.py

7 files changed, 20 insertions, 485 deletions

diff --git a/src/mem/ruby/network/topologies/Crossbar.py b/src/mem/ruby/network/topologies/Crossbar.py
deleted file mode 100644
index 04e01ee1c..000000000
--- a/src/mem/ruby/network/topologies/Crossbar.py
+++ /dev/null
@@ -1,51 +0,0 @@
-# Copyright (c) 2010 Advanced Micro Devices, Inc.
-# All rights reserved.
-#
-# Redistribution and use in source and binary forms, with or without
-# modification, are permitted provided that the following conditions are
-# met: redistributions of source code must retain the above copyright
-# notice, this list of conditions and the following disclaimer;
-# redistributions in binary form must reproduce the above copyright
-# notice, this list of conditions and the following disclaimer in the
-# documentation and/or other materials provided with the distribution;
-# neither the name of the copyright holders nor the names of its
-# contributors may be used to endorse or promote products derived from
-# this software without specific prior written permission.
-#
-# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-#
-# Authors: Steve Reinhardt
-
-from m5.params import *
-from m5.objects import *
-
-class Crossbar(Topology):
-    description='Crossbar'
-
-def makeTopology(nodes, options, IntLink, ExtLink, Router):
-    # Create an individual router for each controller plus one more for the
-    # centralized crossbar.  The large numbers of routers are needed because
-    # external links do not model outgoing bandwidth in the simple network, but
-    # internal links do.
-    cb = Crossbar()
-    cb.routers = [Router(router_id=i) for i in range(len(nodes)+1)]
-    cb.ext_links = [ExtLink(link_id=i, ext_node=n, int_node=cb.routers[i])
-                    for (i, n) in enumerate(nodes)]
-    link_count = len(nodes)
-    xbar = cb.routers[len(nodes)] # the crossbar router is the last router created
-    cb.int_links = [IntLink(link_id=(link_count+i),
-                            node_a=cb.routers[i], node_b=xbar)
-                    for i in range(len(nodes))]
-    return cb
-
-
diff --git a/src/mem/ruby/network/topologies/Mesh.py b/src/mem/ruby/network/topologies/Mesh.py
deleted file mode 100644
index fa6e63354..000000000
--- a/src/mem/ruby/network/topologies/Mesh.py
+++ /dev/null
@@ -1,114 +0,0 @@
-# Copyright (c) 2010 Advanced Micro Devices, Inc.
-# All rights reserved.
-#
-# Redistribution and use in source and binary forms, with or without
-# modification, are permitted provided that the following conditions are
-# met: redistributions of source code must retain the above copyright
-# notice, this list of conditions and the following disclaimer;
-# redistributions in binary form must reproduce the above copyright
-# notice, this list of conditions and the following disclaimer in the
-# documentation and/or other materials provided with the distribution;
-# neither the name of the copyright holders nor the names of its
-# contributors may be used to endorse or promote products derived from
-# this software without specific prior written permission.
-#
-# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-#
-# Authors: Brad Beckmann
-
-from m5.params import *
-from m5.objects import *
-
-class Mesh(Topology):
-    description='Mesh'
-
-# Makes a generic mesh assuming an equal number of cache and directory cntrls
-
-def makeTopology(nodes, options, IntLink, ExtLink, Router):
-
-    num_routers = options.num_cpus
-    num_rows = options.mesh_rows
-
-    # There must be an evenly divisible number of cntrls to routers
-    # Also, obviously the number or rows must be <= the number of routers
-    cntrls_per_router, remainder = divmod(len(nodes), num_routers)
-    assert(num_rows <= num_routers)
-    num_columns = int(num_routers / num_rows)
-    assert(num_columns * num_rows == num_routers)
-
-    # Create the mesh object
-    mesh = Mesh()
-
-    # Create the routers in the mesh
-    mesh.routers = [Router(router_id=i) for i in range(num_routers)]
-
-    # link counter to set unique link ids
-    link_count = 0
-
-    # Add all but the remainder nodes to the list of nodes to be uniformly
-    # distributed across the network.
-    network_nodes = []
-    remainder_nodes = []
-    for node_index in xrange(len(nodes)):
-        if node_index < (len(nodes) - remainder):
-            network_nodes.append(nodes[node_index])
-        else:
-            remainder_nodes.append(nodes[node_index])
-
-    # Connect each node to the appropriate router
-    ext_links = []
-    for (i, n) in enumerate(network_nodes):
-        cntrl_level, router_id = divmod(i, num_routers)
-        assert(cntrl_level < cntrls_per_router)
-        ext_links.append(ExtLink(link_id=link_count, ext_node=n,
-                                 int_node=mesh.routers[router_id]))
-        link_count += 1
-
-    # Connect the remainding nodes to router 0.  These should only be
-    # DMA nodes.
-    for (i, node) in enumerate(remainder_nodes):
-        assert(node.type == 'DMA_Controller')
-        assert(i < remainder)
-        ext_links.append(ExtLink(link_id=link_count, ext_node=node,
-                                 int_node=mesh.routers[0]))
-        link_count += 1
-
-    # Create the mesh links.  First row (east-west) links then column
-    # (north-south) links
-    int_links = []
-    for row in xrange(num_rows):
-        for col in xrange(num_columns):
-            if (col + 1 < num_columns):
-                east_id = col + (row * num_columns)
-                west_id = (col + 1) + (row * num_columns)
-                int_links.append(IntLink(link_id=link_count,
-                                         node_a=mesh.routers[east_id],
-                                         node_b=mesh.routers[west_id],
-                                         weight=1))
-                link_count += 1
-                
-    for col in xrange(num_columns):
-        for row in xrange(num_rows):
-            if (row + 1 < num_rows):
-                north_id = col + (row * num_columns)
-                south_id = col + ((row + 1) * num_columns)
-                int_links.append(IntLink(link_id=link_count,
-                                         node_a=mesh.routers[north_id],
-                                         node_b=mesh.routers[south_id],
-                                         weight=2))
-                link_count += 1
-
-    mesh.int_links = int_links
-    mesh.ext_links = ext_links
-
-    return mesh
diff --git a/src/mem/ruby/network/topologies/MeshDirCorners.py b/src/mem/ruby/network/topologies/MeshDirCorners.py
deleted file mode 100644
index 7be8b9101..000000000
--- a/src/mem/ruby/network/topologies/MeshDirCorners.py
+++ /dev/null
@@ -1,132 +0,0 @@
-# Copyright (c) 2010 Advanced Micro Devices, Inc.
-# All rights reserved.
-#
-# Redistribution and use in source and binary forms, with or without
-# modification, are permitted provided that the following conditions are
-# met: redistributions of source code must retain the above copyright
-# notice, this list of conditions and the following disclaimer;
-# redistributions in binary form must reproduce the above copyright
-# notice, this list of conditions and the following disclaimer in the
-# documentation and/or other materials provided with the distribution;
-# neither the name of the copyright holders nor the names of its
-# contributors may be used to endorse or promote products derived from
-# this software without specific prior written permission.
-#
-# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-#
-# Authors: Brad Beckmann
-
-from m5.params import *
-from m5.objects import *
-
-class MeshDirCorners(Topology):
-    description='MeshDirCorners'
-
-# This file contains a special network creation function.  This
-# networks is not general and will only work with specific system
-# configurations.  The network specified is similar to GEMS old file
-# specified network.
-
-def makeTopology(nodes, options, IntLink, ExtLink, Router):
-    num_routers = options.num_cpus
-    num_rows = options.mesh_rows
-
-    # First determine which nodes are cache cntrls vs. dirs vs. dma
-    cache_nodes = []
-    dir_nodes = []
-    dma_nodes = []
-    for node in nodes:
-        if node.type == 'L1Cache_Controller' or \
-           node.type == 'L2Cache_Controller':
-            cache_nodes.append(node)
-        elif node.type == 'Directory_Controller':
-            dir_nodes.append(node)
-        elif node.type == 'DMA_Controller':
-            dma_nodes.append(node)
-
-    # Obviously the number or rows must be <= the number of routers
-    # and evenly divisible.  Also the number of caches must be a
-    # multiple of the number of routers and the number of directories
-    # must be four.
-    assert(num_rows <= num_routers)
-    num_columns = int(num_routers / num_rows)
-    assert(num_columns * num_rows == num_routers)
-    caches_per_router, remainder = divmod(len(cache_nodes), num_routers)
-    assert(remainder == 0)
-    assert(len(dir_nodes) == 4)
-
-    mesh = MeshDirCorners()
-
-    # Create the routers in the mesh
-    mesh.routers = [Router(router_id=i) for i in range(num_routers)]
-
-    # link counter to set unique link ids
-    link_count = 0
-
-    # Connect each cache controller to the appropriate router
-    ext_links = []
-    for (i, n) in enumerate(cache_nodes):
-        cntrl_level, router_id = divmod(i, num_routers)
-        assert(cntrl_level < caches_per_router)
-        ext_links.append(ExtLink(link_id=link_count, ext_node=n,
-                                 int_node=mesh.routers[router_id]))
-        link_count += 1
-
-    # Connect the dir nodes to the corners.
-    ext_links.append(ExtLink(link_id=link_count, ext_node=dir_nodes[0],
-                             int_node=mesh.routers[0]))
-    link_count += 1
-    ext_links.append(ExtLink(link_id=link_count, ext_node=dir_nodes[1],
-                             int_node=mesh.routers[num_columns - 1]))
-    link_count += 1
-    ext_links.append(ExtLink(link_id=link_count, ext_node=dir_nodes[2],
-                             int_node=mesh.routers[num_routers - num_columns]))
-    link_count += 1
-    ext_links.append(ExtLink(link_id=link_count, ext_node=dir_nodes[3],
-                             int_node=mesh.routers[num_routers - 1]))
-    link_count += 1
-
-    # Connect the dma nodes to router 0.  These should only be DMA nodes.
-    for (i, node) in enumerate(dma_nodes):
-        assert(node.type == 'DMA_Controller')
-        ext_links.append(ExtLink(link_id=link_count, ext_node=node, int_node=mesh.routers[0]))
-
-    # Create the mesh links.  First row (east-west) links then column
-    # (north-south) links
-    int_links = []
-    for row in xrange(num_rows):
-        for col in xrange(num_columns):
-            if (col + 1 < num_columns):
-                east_id = col + (row * num_columns)
-                west_id = (col + 1) + (row * num_columns)
-                int_links.append(IntLink(link_id=link_count,
-                                         node_a=mesh.routers[east_id],
-                                         node_b=mesh.routers[west_id],
-                                         weight=1))
-                link_count += 1
-                
-    for col in xrange(num_columns):
-        for row in xrange(num_rows):
-            if (row + 1 < num_rows):
-                north_id = col + (row * num_columns)
-                south_id = col + ((row + 1) * num_columns)
-                int_links.append(IntLink(link_id=link_count,
-                                         node_a=mesh.routers[north_id],
-                                         node_b=mesh.routers[south_id],
-                                         weight=2))
-                link_count += 1
-
-    mesh.ext_links = ext_links
-    mesh.int_links = int_links
-
-    return mesh
diff --git a/src/mem/ruby/network/topologies/Pt2Pt.py b/src/mem/ruby/network/topologies/Pt2Pt.py
deleted file mode 100644
index f6ca13626..000000000
--- a/src/mem/ruby/network/topologies/Pt2Pt.py
+++ /dev/null
@@ -1,57 +0,0 @@
-# Copyright (c) 2011 Advanced Micro Devices, Inc.
-#               2011 Massachusetts Institute of Technology
-# All rights reserved.
-#
-# Redistribution and use in source and binary forms, with or without
-# modification, are permitted provided that the following conditions are
-# met: redistributions of source code must retain the above copyright
-# notice, this list of conditions and the following disclaimer;
-# redistributions in binary form must reproduce the above copyright
-# notice, this list of conditions and the following disclaimer in the
-# documentation and/or other materials provided with the distribution;
-# neither the name of the copyright holders nor the names of its
-# contributors may be used to endorse or promote products derived from
-# this software without specific prior written permission.
-#
-# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-#
-# Authors: Brad Beckmann
-#          Tushar Krishna
-
-from m5.params import *
-from m5.objects import *
-
-class Pt2Pt(Topology):
-    description='Pt2Pt'
-
-def makeTopology(nodes, options, IntLink, ExtLink, Router):
-    # Create an individual router for each controller, and connect all to all.
-    pt2pt = Pt2Pt()
-    pt2pt.routers = [Router(router_id=i) for i in range(len(nodes))]
-    ext_links = [ExtLink(link_id=i, ext_node=n, int_node=pt2pt.routers[i])
-                 for (i, n) in enumerate(nodes)]
-    link_count = len(nodes)
-
-    int_links = []
-    for i in xrange(len(nodes)):
-        for j in xrange(len(nodes)):
-            if (i != j):
-                link_count += 1
-                int_links.append(IntLink(link_id=link_count,
-                                         node_a=pt2pt.routers[i],
-                                         node_b=pt2pt.routers[j]))
-
-    pt2pt.ext_links = ext_links
-    pt2pt.int_links = int_links
-
-    return pt2pt
diff --git a/src/mem/ruby/network/topologies/SConscript b/src/mem/ruby/network/topologies/SConscript
index a3c41a6d3..3d61f6dd1 100644
--- a/src/mem/ruby/network/topologies/SConscript
+++ b/src/mem/ruby/network/topologies/SConscript
@@ -33,8 +33,4 @@ Import('*')
 if env['PROTOCOL'] == 'None':
     Return()
 
-PySource('', 'Crossbar.py')
-PySource('', 'Mesh.py')
-PySource('', 'MeshDirCorners.py')
-PySource('', 'Pt2Pt.py')
-PySource('', 'Torus.py')
+PySource('', 'TopologyCreator.py')
diff --git a/src/mem/ruby/network/topologies/TopologyCreator.py b/src/mem/ruby/network/topologies/TopologyCreator.py
new file mode 100644
index 000000000..d9b989e77
--- /dev/null
+++ b/src/mem/ruby/network/topologies/TopologyCreator.py
@@ -0,0 +1,19 @@
+
+
+
+
+from m5.params import *
+from m5.objects import *
+
+def instantiateTopology(topology, options, IntLink, ExtLink, Router):
+
+    topo = Topology()
+    topo.description = topology.description
+
+    routers, int_links, ext_links = topology.makeTopology(options, IntLink, ExtLink, Router)
+
+    topo.routers = routers
+    topo.int_links = int_links
+    topo.ext_links = ext_links
+
+    return topo
diff --git a/src/mem/ruby/network/topologies/Torus.py b/src/mem/ruby/network/topologies/Torus.py
deleted file mode 100644
index f3583bfc1..000000000
--- a/src/mem/ruby/network/topologies/Torus.py
+++ /dev/null
@@ -1,126 +0,0 @@
-# Copyright (c) 2011 Advanced Micro Devices, Inc.
-#               2011 Massachusetts Institute of Technology
-# All rights reserved.
-#
-# Redistribution and use in source and binary forms, with or without
-# modification, are permitted provided that the following conditions are
-# met: redistributions of source code must retain the above copyright
-# notice, this list of conditions and the following disclaimer;
-# redistributions in binary form must reproduce the above copyright
-# notice, this list of conditions and the following disclaimer in the
-# documentation and/or other materials provided with the distribution;
-# neither the name of the copyright holders nor the names of its
-# contributors may be used to endorse or promote products derived from
-# this software without specific prior written permission.
-#
-# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-#
-# Authors: Brad Beckmann
-#          Tushar Krishna
-
-from m5.params import *
-from m5.objects import *
-
-class Torus(Topology):
-    description='Torus'
-
-# Makes a generic torus assuming an equal number of cache and directory cntrls
-# Assuming a folded-torus on-chip layout (as shown on gem5 wiki).
-# All links (including the wrap-around ones) are of equal length, double that
-# of a mesh. Thus, each link is assigned a latency of 2 cycles.
-
-def makeTopology(nodes, options, IntLink, ExtLink, Router):
-
-    num_routers = options.num_cpus
-    num_rows = options.mesh_rows
-
-    # There must be an evenly divisible number of cntrls to routers
-    # Also, obviously the number or rows must be <= the number of routers
-    cntrls_per_router, remainder = divmod(len(nodes), num_routers)
-    assert(num_rows <= num_routers)
-    num_columns = int(num_routers / num_rows)
-    assert(num_columns * num_rows == num_routers)
-
-    # Create the torus object
-    torus = Torus()
-
-    # Create the routers in the torus
-    torus.routers = [Router(router_id=i) for i in range(num_routers)]
-
-    # link counter to set unique link ids
-    link_count = 0
-
-    # Add all but the remainder nodes to the list of nodes to be uniformly
-    # distributed across the network.
-    network_nodes = []
-    remainder_nodes = []
-    for node_index in xrange(len(nodes)):
-        if node_index < (len(nodes) - remainder):
-            network_nodes.append(nodes[node_index])
-        else:
-            remainder_nodes.append(nodes[node_index])
-
-    # Connect each node to the appropriate router
-    ext_links = []
-    for (i, n) in enumerate(network_nodes):
-        cntrl_level, router_id = divmod(i, num_routers)
-        assert(cntrl_level < cntrls_per_router)
-        ext_links.append(ExtLink(link_id=link_count, ext_node=n, 
-                                 int_node=torus.routers[router_id]))
-        link_count += 1
-
-    # Connect the remainding nodes to router 0.  These should only be
-    # DMA nodes.
-    for (i, node) in enumerate(remainder_nodes):
-        assert(node.type == 'DMA_Controller')
-        assert(i < remainder)
-        ext_links.append(ExtLink(link_id=link_count, ext_node=node,
-                                 int_node=torus.routers[0]))
-        link_count += 1
-
-    # Create the torus links.  First row (east-west) links then column
-    # (north-south) links
-    # column links are given higher weights to implement XY routing
-    int_links = []
-    for row in xrange(num_rows):
-        for col in xrange(num_columns):
-            west_id = col + (row * num_columns)
-            if (col + 1 < num_columns):
-                east_id = (col + 1) + (row * num_columns)
-            else:
-                east_id = (row * num_columns)
-            int_links.append(IntLink(link_id=link_count,
-                                     node_a=torus.routers[east_id],
-                                     node_b=torus.routers[west_id],
-                                     latency=2,
-                                     weight=1))
-            link_count += 1
-
-    for col in xrange(num_columns):
-        for row in xrange(num_rows):
-            north_id = col + (row * num_columns)
-            if (row + 1 < num_rows):
-                south_id = col + ((row + 1) * num_columns)
-            else:
-                south_id = col
-            int_links.append(IntLink(link_id=link_count,
-                                     node_a=torus.routers[north_id],
-                                     node_b=torus.routers[south_id],
-                                     latency=2,
-                                     weight=2))
-            link_count += 1
-
-    torus.ext_links = ext_links
-    torus.int_links = int_links
-
-    return torus