VOM: IP route ECMP support

Change-Id: Iede0c30aacfe7289f428062bb9540410097c40e2
Signed-off-by: Neale Ranns <nranns@cisco.com>

3 files changed, 56 insertions, 24 deletions

diff --git a/extras/vom/vom/route.cpp b/extras/vom/vom/route.cpp
index c713de9ee99..5aed82bac2a 100644
--- a/extras/vom/vom/route.cpp
+++ b/extras/vom/vom/route.cpp
@@ -339,8 +339,9 @@ void
 ip_route::sweep()
 {
   if (m_hw) {
-    HW::enqueue(
-      new ip_route_cmds::delete_cmd(m_hw, m_rd->table_id(), m_prefix));
+    for (auto& p : m_paths)
+      HW::enqueue(
+        new ip_route_cmds::delete_cmd(m_hw, m_rd->table_id(), m_prefix, p));
   }
   HW::write();
 }
@@ -349,8 +350,9 @@ void
 ip_route::replay()
 {
   if (m_hw) {
-    HW::enqueue(
-      new ip_route_cmds::update_cmd(m_hw, m_rd->table_id(), m_prefix, m_paths));
+    for (auto& p : m_paths)
+      HW::enqueue(
+        new ip_route_cmds::update_cmd(m_hw, m_rd->table_id(), m_prefix, p));
   }
 }
 std::string
@@ -367,12 +369,37 @@ ip_route::to_string() const
 void
 ip_route::update(const ip_route& r)
 {
-  /*
-* create the table if it is not yet created
-*/
   if (rc_t::OK != m_hw.rc()) {
-    HW::enqueue(
-      new ip_route_cmds::update_cmd(m_hw, m_rd->table_id(), m_prefix, m_paths));
+    /*
+     * route not yet installed. install each of the desired paths
+     */
+    m_paths = r.m_paths;
+
+    for (auto& p : m_paths)
+      HW::enqueue(
+        new ip_route_cmds::update_cmd(m_hw, m_rd->table_id(), m_prefix, p));
+  } else {
+    /*
+     * add each path that is not installed yet and remove each that is no longer
+     * wanted
+     */
+    path_list_t to_add;
+    set_difference(r.m_paths.begin(), r.m_paths.end(), m_paths.begin(),
+                   m_paths.end(), std::inserter(to_add, to_add.begin()));
+
+    for (auto& p : to_add)
+      HW::enqueue(
+        new ip_route_cmds::update_cmd(m_hw, m_rd->table_id(), m_prefix, p));
+
+    path_list_t to_del;
+    set_difference(m_paths.begin(), m_paths.end(), r.m_paths.begin(),
+                   r.m_paths.end(), std::inserter(to_del, to_del.begin()));
+
+    for (auto& p : to_del)
+      HW::enqueue(
+        new ip_route_cmds::delete_cmd(m_hw, m_rd->table_id(), m_prefix, p));
+
+    m_paths = r.m_paths;
   }
 }
 
diff --git a/extras/vom/vom/route_cmds.cpp b/extras/vom/vom/route_cmds.cpp
index 26d6593df78..e3f635fe09a 100644
--- a/extras/vom/vom/route_cmds.cpp
+++ b/extras/vom/vom/route_cmds.cpp
@@ -25,20 +25,19 @@ namespace ip_route_cmds {
 update_cmd::update_cmd(HW::item<bool>& item,
                        table_id_t id,
                        const prefix_t& prefix,
-                       const path_list_t& paths)
+                       const path& path)
   : rpc_cmd(item)
   , m_id(id)
   , m_prefix(prefix)
-  , m_paths(paths)
+  , m_path(path)
 {
-  // no multipath yet.
-  assert(paths.size() == 1);
 }
 
 bool
 update_cmd::operator==(const update_cmd& other) const
 {
-  return ((m_prefix == other.m_prefix) && (m_id == other.m_id));
+  return ((m_prefix == other.m_prefix) && (m_id == other.m_id) &&
+          (m_path == other.m_path));
 }
 
 rc_t
@@ -54,9 +53,7 @@ update_cmd::issue(connection& con)
 
   m_prefix.to_vpp(&payload.is_ipv6, payload.dst_address,
                   &payload.dst_address_length);
-
-  for (auto& p : m_paths)
-    to_vpp(p, payload);
+  to_vpp(m_path, payload);
 
   VAPI_CALL(req.execute());
 
@@ -68,24 +65,27 @@ update_cmd::to_string() const
 {
   std::ostringstream s;
   s << "ip-route-create: " << m_hw_item.to_string() << " table-id:" << m_id
-    << " prefix:" << m_prefix.to_string() << " paths:" << m_paths;
+    << " prefix:" << m_prefix.to_string() << " paths:" << m_path.to_string();
 
   return (s.str());
 }
 
 delete_cmd::delete_cmd(HW::item<bool>& item,
                        table_id_t id,
-                       const prefix_t& prefix)
+                       const prefix_t& prefix,
+                       const path& path)
   : rpc_cmd(item)
   , m_id(id)
   , m_prefix(prefix)
+  , m_path(path)
 {
 }
 
 bool
 delete_cmd::operator==(const delete_cmd& other) const
 {
-  return ((m_prefix == other.m_prefix) && (m_id == other.m_id));
+  return ((m_prefix == other.m_prefix) && (m_id == other.m_id) &&
+          (m_path == other.m_path));
 }
 
 rc_t
@@ -99,6 +99,7 @@ delete_cmd::issue(connection& con)
 
   m_prefix.to_vpp(&payload.is_ipv6, payload.dst_address,
                   &payload.dst_address_length);
+  to_vpp(m_path, payload);
 
   VAPI_CALL(req.execute());
 
@@ -113,7 +114,7 @@ delete_cmd::to_string() const
 {
   std::ostringstream s;
   s << "ip-route-delete: " << m_hw_item.to_string() << " id:" << m_id
-    << " prefix:" << m_prefix.to_string();
+    << " prefix:" << m_prefix.to_string() << " paths:" << m_path.to_string();
 
   return (s.str());
 }
diff --git a/extras/vom/vom/route_cmds.hpp b/extras/vom/vom/route_cmds.hpp
index 2e6ce73068c..6db7b5894ef 100644
--- a/extras/vom/vom/route_cmds.hpp
+++ b/extras/vom/vom/route_cmds.hpp
@@ -38,7 +38,7 @@ public:
   update_cmd(HW::item<bool>& item,
              table_id_t id,
              const prefix_t& prefix,
-             const path_list_t& paths);
+             const path& path);
 
   /**
    * Issue the command to VPP/HW
@@ -58,7 +58,7 @@ public:
 private:
   route::table_id_t m_id;
   prefix_t m_prefix;
-  const path_list_t m_paths;
+  const path m_path;
 };
 
 /**
@@ -70,7 +70,10 @@ public:
   /**
    * Constructor
    */
-  delete_cmd(HW::item<bool>& item, table_id_t id, const prefix_t& prefix);
+  delete_cmd(HW::item<bool>& item,
+             table_id_t id,
+             const prefix_t& prefix,
+             const path& path);
 
   /**
    * Issue the command to VPP/HW
@@ -90,6 +93,7 @@ public:
 private:
   route::table_id_t m_id;
   prefix_t m_prefix;
+  const path m_path;
 };
 
 /**