bridge: Refactor bridge_reconfigure().
[openvswitch] / vswitchd / bridge.c
index 15f6cb7d088a65fa76571b0b10ccb893f1cb1cce..077d9ee15f34ec0a551eb5c9a1da03f92a1f7606 100644 (file)
@@ -60,6 +60,19 @@ VLOG_DEFINE_THIS_MODULE(bridge);
 
 COVERAGE_DEFINE(bridge_reconfigure);
 
+/* Configuration of an uninstantiated iface. */
+struct if_cfg {
+    struct hmap_node hmap_node;         /* Node in bridge's if_cfg_todo. */
+    const struct ovsrec_interface *cfg; /* Interface record. */
+    const struct ovsrec_port *parent;   /* Parent port record. */
+};
+
+/* OpenFlow port slated for removal from ofproto. */
+struct ofpp_garbage {
+    struct list list_node;      /* Node in bridge's ofpp_garbage. */
+    uint16_t ofp_port;          /* Port to be deleted. */
+};
+
 struct iface {
     /* These members are always valid. */
     struct list port_elem;      /* Element in struct port's "ifaces" list. */
@@ -113,6 +126,10 @@ struct bridge {
     struct hmap ifaces;         /* "struct iface"s indexed by ofp_port. */
     struct hmap iface_by_name;  /* "struct iface"s indexed by name. */
 
+    struct list ofpp_garbage;   /* "struct ofpp_garbage" slated for removal. */
+    struct hmap if_cfg_todo;    /* "struct if_cfg"s slated for creation.
+                                   Indexed on 'cfg->name'. */
+
     /* Port mirroring. */
     struct hmap mirrors;        /* "struct mirror" indexed by UUID. */
 
@@ -151,11 +168,10 @@ static long long int db_limiter = LLONG_MIN;
  * This allows the rest of the code to catch up on important things like
  * forwarding packets. */
 #define OFP_PORT_ACTION_WINDOW 10
-static bool need_reconfigure = false;
+static bool reconfiguring = false;
 
 static void add_del_bridges(const struct ovsrec_open_vswitch *);
-static void bridge_del_ofprotos(void);
-static bool bridge_add_ofprotos(struct bridge *);
+static void bridge_update_ofprotos(void);
 static void bridge_create(const struct ovsrec_bridge *);
 static void bridge_destroy(struct bridge *);
 static struct bridge *bridge_lookup(const char *name);
@@ -165,10 +181,6 @@ static size_t bridge_get_controllers(const struct bridge *br,
                                      struct ovsrec_controller ***controllersp);
 static void bridge_add_del_ports(struct bridge *,
                                  const unsigned long int *splinter_vlans);
-static void bridge_add_ofproto_ports(struct bridge *,
-                                     long long int *port_action_timer);
-static void bridge_del_ofproto_ports(struct bridge *,
-                                     long long int *port_action_timer);
 static void bridge_refresh_ofp_port(struct bridge *);
 static void bridge_configure_datapath_id(struct bridge *);
 static void bridge_configure_flow_eviction_threshold(struct bridge *);
@@ -187,6 +199,9 @@ static void bridge_pick_local_hw_addr(struct bridge *,
 static uint64_t bridge_pick_datapath_id(struct bridge *,
                                         const uint8_t bridge_ea[ETH_ADDR_LEN],
                                         struct iface *hw_addr_iface);
+static void bridge_queue_if_cfg(struct bridge *,
+                                const struct ovsrec_interface *,
+                                const struct ovsrec_port *);
 static uint64_t dpid_from_hash(const void *, size_t nbytes);
 static bool bridge_has_bond_fake_iface(const struct bridge *,
                                        const char *name);
@@ -195,7 +210,6 @@ static bool port_is_bond_fake_iface(const struct port *);
 static unixctl_cb_func qos_unixctl_show;
 
 static struct port *port_create(struct bridge *, const struct ovsrec_port *);
-static void port_add_ifaces(struct port *);
 static void port_del_ifaces(struct port *);
 static void port_destroy(struct port *);
 static struct port *port_lookup(const struct bridge *, const char *name);
@@ -214,11 +228,12 @@ static bool mirror_configure(struct mirror *);
 static void mirror_refresh_stats(struct mirror *);
 
 static void iface_configure_lacp(struct iface *, struct lacp_slave_settings *);
-static struct iface *iface_create(struct port *port,
-                                  const struct ovsrec_interface *if_cfg);
+static void iface_create(struct bridge *, struct if_cfg *, int ofp_port);
+static void iface_refresh_type(struct iface *);
 static void iface_destroy(struct iface *);
 static struct iface *iface_lookup(const struct bridge *, const char *name);
 static struct iface *iface_find(const char *name);
+static struct if_cfg *if_cfg_lookup(const struct bridge *, const char *name);
 static struct iface *iface_from_ofp_port(const struct bridge *,
                                          uint16_t ofp_port);
 static void iface_set_mac(struct iface *);
@@ -407,23 +422,19 @@ static void
 bridge_reconfigure(const struct ovsrec_open_vswitch *ovs_cfg)
 {
     unsigned long int *splinter_vlans;
-    long long int port_action_timer;
-    struct sockaddr_in *managers;
-    struct bridge *br, *next;
-    int sflow_bridge_number;
-    size_t n_managers;
+    struct bridge *br;
 
     COVERAGE_INC(bridge_reconfigure);
 
-    port_action_timer = LLONG_MAX;
-    need_reconfigure = false;
+    assert(!reconfiguring);
+    reconfiguring = true;
 
-    /* Create and destroy "struct bridge"s, "struct port"s, and "struct
-     * iface"s according to 'ovs_cfg', with only very minimal configuration
-     * otherwise.
+    /* Destroy "struct bridge"s, "struct port"s, and "struct iface"s according
+     * to 'ovs_cfg' while update the "if_cfg_queue", with only very minimal
+     * configuration otherwise.
      *
-     * This is mostly an update to bridge data structures.  Very little is
-     * pushed down to ofproto or lower layers. */
+     * This is mostly an update to bridge data structures. Nothing is pushed
+     * down to ofproto or lower layers. */
     add_del_bridges(ovs_cfg);
     splinter_vlans = collect_splinter_vlans(ovs_cfg);
     HMAP_FOR_EACH (br, node, &all_bridges) {
@@ -431,39 +442,79 @@ bridge_reconfigure(const struct ovsrec_open_vswitch *ovs_cfg)
     }
     free(splinter_vlans);
 
-    /* Delete all datapaths and datapath ports that are no longer configured.
-     *
-     * The kernel will reject any attempt to add a given port to a datapath if
-     * that port already belongs to a different datapath, so we must do all
-     * port deletions before any port additions.  A datapath always has a
-     * "local port" so we must delete not-configured datapaths too. */
-    bridge_del_ofprotos();
+    /* Delete datapaths that are no longer configured, and create ones which
+     * don't exist but should. */
+    bridge_update_ofprotos();
+
+    /* Make sure each "struct iface" has a correct ofp_port in its ofproto. */
     HMAP_FOR_EACH (br, node, &all_bridges) {
-        if (br->ofproto) {
-            bridge_del_ofproto_ports(br, &port_action_timer);
+        bridge_refresh_ofp_port(br);
+    }
+
+    /* Clear database records for "if_cfg"s which haven't been instantiated. */
+    HMAP_FOR_EACH (br, node, &all_bridges) {
+        struct if_cfg *if_cfg;
+
+        HMAP_FOR_EACH (if_cfg, hmap_node, &br->if_cfg_todo) {
+            iface_clear_db_record(if_cfg->cfg);
         }
     }
+}
 
-    /* Create datapaths and datapath ports that are missing.
-     *
-     * After this is done, we have our final set of bridges, ports, and
-     * interfaces.  Every "struct bridge" has an ofproto, every "struct port"
-     * has at least one iface, every "struct iface" has a valid ofp_port and
-     * netdev. */
-    HMAP_FOR_EACH_SAFE (br, next, node, &all_bridges) {
-        if (!br->ofproto) {
-            if (bridge_add_ofprotos(br)) {
-                bridge_del_ofproto_ports(br, &port_action_timer);
-            } else {
-                bridge_destroy(br);
+static bool
+bridge_reconfigure_ofp(void)
+{
+    long long int deadline;
+    struct bridge *br;
+
+    time_refresh();
+    deadline = time_msec() + OFP_PORT_ACTION_WINDOW;
+
+    /* The kernel will reject any attempt to add a given port to a datapath if
+     * that port already belongs to a different datapath, so we must do all
+     * port deletions before any port additions. */
+    HMAP_FOR_EACH (br, node, &all_bridges) {
+        struct ofpp_garbage *garbage, *next;
+
+        LIST_FOR_EACH_SAFE (garbage, next, list_node, &br->ofpp_garbage) {
+            ofproto_port_del(br->ofproto, garbage->ofp_port);
+            list_remove(&garbage->list_node);
+            free(garbage);
+
+            time_refresh();
+            if (time_msec() >= deadline) {
+                return false;
             }
         }
     }
+
     HMAP_FOR_EACH (br, node, &all_bridges) {
-        bridge_refresh_ofp_port(br);
-        bridge_add_ofproto_ports(br, &port_action_timer);
+        struct if_cfg *if_cfg, *next;
+
+        HMAP_FOR_EACH_SAFE (if_cfg, next, hmap_node, &br->if_cfg_todo) {
+            iface_create(br, if_cfg, -1);
+            time_refresh();
+            if (time_msec() >= deadline) {
+                return false;
+            }
+        }
     }
 
+    return true;
+}
+
+static bool
+bridge_reconfigure_continue(const struct ovsrec_open_vswitch *ovs_cfg)
+{
+    struct sockaddr_in *managers;
+    int sflow_bridge_number;
+    size_t n_managers;
+    struct bridge *br;
+    bool done;
+
+    assert(reconfiguring);
+    done = bridge_reconfigure_ofp();
+
     /* Complete the configuration. */
     sflow_bridge_number = 0;
     collect_in_band_managers(ovs_cfg, &managers, &n_managers);
@@ -497,22 +548,27 @@ bridge_reconfigure(const struct ovsrec_open_vswitch *ovs_cfg)
     }
     free(managers);
 
-    if (!need_reconfigure) {
+    if (done) {
         /* ovs-vswitchd has completed initialization, so allow the process that
          * forked us to exit successfully. */
         daemonize_complete();
+        reconfiguring = false;
     }
+
+    return done;
 }
 
-/* Iterate over all ofprotos and delete any of them that do not have a
- * configured bridge or that are the wrong type. */
+/* Delete ofprotos which aren't configured or have the wrong type.  Create
+ * ofprotos which don't exist but need to. */
 static void
-bridge_del_ofprotos(void)
+bridge_update_ofprotos(void)
 {
+    struct bridge *br, *next;
     struct sset names;
     struct sset types;
     const char *type;
 
+    /* Delete ofprotos with no bridge or with the wrong type. */
     sset_init(&names);
     sset_init(&types);
     ofproto_enumerate_types(&types);
@@ -521,7 +577,7 @@ bridge_del_ofprotos(void)
 
         ofproto_enumerate_names(type, &names);
         SSET_FOR_EACH (name, &names) {
-            struct bridge *br = bridge_lookup(name);
+            br = bridge_lookup(name);
             if (!br || strcmp(type, br->type)) {
                 ofproto_delete(name, type);
             }
@@ -529,17 +585,44 @@ bridge_del_ofprotos(void)
     }
     sset_destroy(&names);
     sset_destroy(&types);
-}
 
-static bool
-bridge_add_ofprotos(struct bridge *br)
-{
-    int error = ofproto_create(br->name, br->type, &br->ofproto);
-    if (error) {
-        VLOG_ERR("failed to create bridge %s: %s", br->name, strerror(error));
-        return false;
+    /* Add ofprotos for bridges which don't have one yet. */
+    HMAP_FOR_EACH_SAFE (br, next, node, &all_bridges) {
+        struct bridge *br2;
+        int error;
+
+        if (br->ofproto) {
+            continue;
+        }
+
+        /* Remove ports from any datapath with the same name as 'br'.  If we
+         * don't do this, creating 'br''s ofproto will fail because a port with
+         * the same name as its local port already exists. */
+        HMAP_FOR_EACH (br2, node, &all_bridges) {
+            struct ofproto_port ofproto_port;
+
+            if (!br2->ofproto) {
+                continue;
+            }
+
+            if (!ofproto_port_query_by_name(br2->ofproto, br->name,
+                                            &ofproto_port)) {
+                error = ofproto_port_del(br2->ofproto, ofproto_port.ofp_port);
+                if (error) {
+                    VLOG_ERR("failed to delete port %s: %s", ofproto_port.name,
+                             strerror(error));
+                }
+                ofproto_port_destroy(&ofproto_port);
+            }
+        }
+
+        error = ofproto_create(br->name, br->type, &br->ofproto);
+        if (error) {
+            VLOG_ERR("failed to create bridge %s: %s", br->name,
+                     strerror(error));
+            bridge_destroy(br);
+        }
     }
-    return true;
 }
 
 static void
@@ -1050,80 +1133,6 @@ add_del_bridges(const struct ovsrec_open_vswitch *cfg)
     shash_destroy(&new_br);
 }
 
-static bool
-may_port_action(long long int *port_action_timer)
-{
-    if (need_reconfigure) {
-        return false;
-    }
-
-    time_refresh();
-    if (*port_action_timer == LLONG_MAX) {
-        *port_action_timer = time_msec() + OFP_PORT_ACTION_WINDOW;
-    } else if (time_msec() > *port_action_timer) {
-        need_reconfigure = true;
-        return false;
-    }
-    return true;
-}
-
-/* Delete each ofproto port on 'br' that doesn't have a corresponding "struct
- * iface".
- *
- * The kernel will reject any attempt to add a given port to a datapath if that
- * port already belongs to a different datapath, so we must do all port
- * deletions before any port additions. */
-static void
-bridge_del_ofproto_ports(struct bridge *br,
-                         long long int *port_action_timer)
-{
-    struct ofproto_port_dump dump;
-    struct ofproto_port ofproto_port;
-
-    OFPROTO_PORT_FOR_EACH (&ofproto_port, &dump, br->ofproto) {
-        const char *name = ofproto_port.name;
-        struct iface *iface;
-        const char *type;
-        int error;
-
-        /* Ignore the local port.  We can't change it anyhow. */
-        if (!strcmp(name, br->name)) {
-            continue;
-        }
-
-        /* Get the type that 'ofproto_port' should have (ordinarily the
-         * type of its corresponding iface) or NULL if it should be
-         * deleted. */
-        iface = iface_lookup(br, name);
-        type = (iface ? iface->type
-                : bridge_has_bond_fake_iface(br, name) ? "internal"
-                : NULL);
-
-        /* If it's the wrong type then delete the ofproto port. */
-        if (type
-            && !strcmp(ofproto_port.type, type)
-            && (!iface || !iface->netdev
-                || !strcmp(netdev_get_type(iface->netdev), type))) {
-            continue;
-        }
-
-        if (may_port_action(port_action_timer)) {
-            error = ofproto_port_del(br->ofproto, ofproto_port.ofp_port);
-            if (error) {
-                VLOG_WARN("bridge %s: failed to remove %s interface (%s)",
-                          br->name, name, strerror(error));
-            } else {
-                VLOG_INFO("bridge %s: removed interface %s (%d)", br->name,
-                          name, ofproto_port.ofp_port);
-            }
-        }
-        if (iface) {
-            netdev_close(iface->netdev);
-            iface->netdev = NULL;
-        }
-    }
-}
-
 static void
 iface_set_ofp_port(struct iface *iface, int ofp_port)
 {
@@ -1135,14 +1144,29 @@ iface_set_ofp_port(struct iface *iface, int ofp_port)
     iface_set_ofport(iface->cfg, ofp_port);
 }
 
+static void
+bridge_ofproto_port_del(struct bridge *br, struct ofproto_port ofproto_port)
+{
+    int error = ofproto_port_del(br->ofproto, ofproto_port.ofp_port);
+    if (error) {
+        VLOG_WARN("bridge %s: failed to remove %s interface (%s)",
+                  br->name, ofproto_port.name, strerror(error));
+    } else {
+        VLOG_INFO("bridge %s: removed interface %s (%d)", br->name,
+                  ofproto_port.name, ofproto_port.ofp_port);
+    }
+}
+
+/* Update bridges "if_cfg"s, "struct port"s, and "struct iface"s to be
+ * consistent with the ofp_ports in "br->ofproto". */
 static void
 bridge_refresh_ofp_port(struct bridge *br)
 {
     struct ofproto_port_dump dump;
     struct ofproto_port ofproto_port;
-    struct port *port;
+    struct port *port, *port_next;
 
-    /* Clear all the "ofp_port"es. */
+    /* Clear each "struct iface"s ofp_port so we can get its correct value. */
     hmap_clear(&br->ifaces);
     HMAP_FOR_EACH (port, hmap_node, &br->ports) {
         struct iface *iface;
@@ -1152,7 +1176,9 @@ bridge_refresh_ofp_port(struct bridge *br)
         }
     }
 
-    /* Obtain the correct "ofp_port"s from ofproto. */
+    /* Obtain the correct "ofp_port"s from ofproto. Find any if_cfg's which
+     * already exist in the datapath and promote them to full fledged "struct
+     * iface"s.  Mark ports in the datapath which don't belong as garbage. */
     OFPROTO_PORT_FOR_EACH (&ofproto_port, &dump, br->ofproto) {
         struct iface *iface = iface_lookup(br, ofproto_port.name);
         if (iface) {
@@ -1162,149 +1188,185 @@ bridge_refresh_ofp_port(struct bridge *br)
             } else if (iface_from_ofp_port(br, ofproto_port.ofp_port)) {
                 VLOG_WARN("bridge %s: interface %"PRIu16" reported twice",
                           br->name, ofproto_port.ofp_port);
-            } else {
+            } else if (!strcmp(ofproto_port.type, iface->type)) {
                 iface_set_ofp_port(iface, ofproto_port.ofp_port);
+            } else {
+                /* Port has incorrect type so delete it later. */
+            }
+        } else {
+            struct if_cfg *if_cfg = if_cfg_lookup(br, ofproto_port.name);
+
+            if (if_cfg) {
+                iface_create(br, if_cfg, ofproto_port.ofp_port);
+            } else if (bridge_has_bond_fake_iface(br, ofproto_port.name)
+                       && strcmp(ofproto_port.type, "internal")) {
+                /* Bond fake iface with the wrong type. */
+                bridge_ofproto_port_del(br, ofproto_port);
+            } else {
+                struct ofpp_garbage *garbage = xmalloc(sizeof *garbage);
+                garbage->ofp_port = ofproto_port.ofp_port;
+                list_push_front(&br->ofpp_garbage, &garbage->list_node);
             }
         }
     }
+
+    /* Some ifaces may not have "ofp_port"s in ofproto and therefore don't
+     * deserve to have "struct iface"s.  Demote these to "if_cfg"s so that
+     * later they can be added to ofproto. */
+    HMAP_FOR_EACH_SAFE (port, port_next, hmap_node, &br->ports) {
+        struct iface *iface, *iface_next;
+
+        LIST_FOR_EACH_SAFE (iface, iface_next, port_elem, &port->ifaces) {
+            if (iface->ofp_port < 0) {
+                bridge_queue_if_cfg(br, iface->cfg, port->cfg);
+                iface_destroy(iface);
+            }
+        }
+
+        if (list_is_empty(&port->ifaces)) {
+            port_destroy(port);
+        }
+    }
 }
 
-/* Add an ofproto port for any "struct iface" that doesn't have one.
- * Delete any "struct iface" for which this fails.
- * Delete any "struct port" that thereby ends up with no ifaces. */
+/* Creates a new iface on 'br' based on 'if_cfg'.  The new iface has OpenFlow
+ * port number 'ofp_port'.  If ofp_port is negative, an OpenFlow port is
+ * automatically allocated for the iface.  Takes ownership of and
+ * deallocates 'if_cfg'. */
 static void
-bridge_add_ofproto_ports(struct bridge *br,
-                         long long int *port_action_timer)
+iface_create(struct bridge *br, struct if_cfg *if_cfg, int ofp_port)
 {
-    struct port *port, *next_port;
+    struct ofproto_port ofproto_port;
+    struct iface *iface;
+    struct port *port;
+    int error;
 
-    HMAP_FOR_EACH_SAFE (port, next_port, hmap_node, &br->ports) {
-        struct iface *iface, *next_iface;
-        struct ofproto_port ofproto_port;
+    assert(!iface_lookup(br, if_cfg->cfg->name));
 
-        LIST_FOR_EACH_SAFE (iface, next_iface, port_elem, &port->ifaces) {
-            int error;
+    port = port_lookup(br, if_cfg->parent->name);
+    if (!port) {
+        port = port_create(br, if_cfg->parent);
+    }
 
-            if (iface->ofp_port < 0 && !may_port_action(port_action_timer)) {
-                iface_clear_db_record(iface->cfg);
-                iface_destroy(iface);
-                continue;
-            }
+    iface = xzalloc(sizeof *iface);
+    iface->port = port;
+    iface->name = xstrdup(if_cfg->cfg->name);
+    iface->ofp_port = -1;
+    iface->netdev = NULL;
+    iface->cfg = if_cfg->cfg;
+    iface->need_refresh = true;
+    hmap_insert(&br->iface_by_name, &iface->name_node,
+                hash_string(iface->name, 0));
+    list_push_back(&port->ifaces, &iface->port_elem);
+    iface_refresh_type(iface);
+    if (ofp_port >= 0) {
+        iface_set_ofp_port(iface, ofp_port);
+    }
 
-            /* Open the netdev. */
-            if (!iface->netdev) {
-                error = netdev_open(iface->name, iface->type, &iface->netdev);
-                if (error) {
-                    VLOG_WARN("could not open network device %s (%s)",
-                              iface->name, strerror(error));
-                }
+    hmap_remove(&br->if_cfg_todo, &if_cfg->hmap_node);
+    free(if_cfg);
+    if_cfg = NULL;
 
-                if (iface->netdev
-                    && port->cfg->vlan_mode
-                    && !strcmp(port->cfg->vlan_mode, "splinter")) {
-                    netdev_turn_flags_on(iface->netdev, NETDEV_UP, true);
-                }
-            } else {
-                error = 0;
-            }
+    error = netdev_open(iface->name, iface->type, &iface->netdev);
+    if (error) {
+        VLOG_WARN("could not open network device %s (%s)", iface->name,
+                  strerror(error));
+    }
 
-            /* Configure the netdev. */
-            if (iface->netdev) {
-                struct shash args;
+    if (iface->netdev
+        && port->cfg->vlan_mode
+        && !strcmp(port->cfg->vlan_mode, "splinter")) {
+        netdev_turn_flags_on(iface->netdev, NETDEV_UP, true);
+    }
 
-                shash_init(&args);
-                shash_from_ovs_idl_map(iface->cfg->key_options,
-                                       iface->cfg->value_options,
-                                       iface->cfg->n_options, &args);
-                error = netdev_set_config(iface->netdev, &args);
-                shash_destroy(&args);
+    /* Configure the netdev. */
+    if (iface->netdev) {
+        struct shash args;
 
-                if (error) {
-                    VLOG_WARN("could not configure network device %s (%s)",
-                              iface->name, strerror(error));
-                    netdev_close(iface->netdev);
-                    iface->netdev = NULL;
-                }
-            }
+        shash_init(&args);
+        shash_from_ovs_idl_map(iface->cfg->key_options,
+                               iface->cfg->value_options,
+                               iface->cfg->n_options, &args);
+        error = netdev_set_config(iface->netdev, &args);
+        shash_destroy(&args);
 
-            /* Add the port, if necessary. */
-            if (iface->netdev && iface->ofp_port < 0) {
-                uint16_t ofp_port;
-                int error;
-
-                error = ofproto_port_add(br->ofproto, iface->netdev,
-                                         &ofp_port);
-                if (!error) {
-                    VLOG_INFO("bridge %s: added interface %s (%d)", br->name,
-                              iface->name, ofp_port);
-                    iface_set_ofp_port(iface, ofp_port);
-                } else {
-                    netdev_close(iface->netdev);
-                    iface->netdev = NULL;
-                }
-            }
+        if (error) {
+            VLOG_WARN("could not configure network device %s (%s)",
+                      iface->name, strerror(error));
+            netdev_close(iface->netdev);
+            iface->netdev = NULL;
+        }
+    }
 
-            /* Populate stats columns in new Interface rows. */
-            if (iface->netdev && iface->need_refresh) {
-                iface_refresh_stats(iface);
-                iface_refresh_status(iface);
-                iface->need_refresh = false;
-            }
+    /* Add the port, if necessary. */
+    if (iface->netdev && iface->ofp_port < 0) {
+        uint16_t new_ofp_port;
+        int error;
 
-            /* Delete the iface if we failed. */
-            if (iface->netdev && iface->ofp_port >= 0) {
-                VLOG_DBG("bridge %s: interface %s is on port %d",
-                         br->name, iface->name, iface->ofp_port);
-            } else {
-                if (iface->netdev) {
-                    VLOG_ERR("bridge %s: missing %s interface, dropping",
-                             br->name, iface->name);
-                } else {
-                    /* We already reported a related error, don't bother
-                     * duplicating it. */
-                }
-                if (!ofproto_port_query_by_name(br->ofproto, port->name,
-                                                &ofproto_port)) {
-                    VLOG_INFO("bridge %s: removed interface %s (%d)",
-                              br->name, port->name, ofproto_port.ofp_port);
-                    ofproto_port_del(br->ofproto, ofproto_port.ofp_port);
-                    ofproto_port_destroy(&ofproto_port);
-                }
-                iface_clear_db_record(iface->cfg);
-                iface_destroy(iface);
-            }
+        error = ofproto_port_add(br->ofproto, iface->netdev, &new_ofp_port);
+        if (!error) {
+            VLOG_INFO("bridge %s: added interface %s (%d)", br->name,
+                      iface->name, ofp_port);
+            iface_set_ofp_port(iface, new_ofp_port);
+        } else {
+            netdev_close(iface->netdev);
+            iface->netdev = NULL;
         }
+    }
 
-        if (list_is_empty(&port->ifaces)) {
-            if (!need_reconfigure) {
-                VLOG_WARN("%s port has no interfaces, dropping", port->name);
-            }
-            port_destroy(port);
-            continue;
+    /* Populate stats columns in new Interface rows. */
+    if (iface->netdev && iface->need_refresh) {
+        iface_refresh_stats(iface);
+        iface_refresh_status(iface);
+        iface->need_refresh = false;
+    }
+
+    /* Delete the iface if we failed. */
+    if (iface->netdev && iface->ofp_port >= 0) {
+        VLOG_DBG("bridge %s: interface %s is on port %d",
+                 br->name, iface->name, iface->ofp_port);
+    } else {
+        if (iface->netdev) {
+            VLOG_ERR("bridge %s: missing %s interface, dropping",
+                     br->name, iface->name);
+        } else {
+            /* We already reported a related error, don't bother
+             * duplicating it. */
         }
+        if (!ofproto_port_query_by_name(br->ofproto, port->name,
+                                        &ofproto_port)) {
+            VLOG_INFO("bridge %s: removed interface %s (%d)",
+                      br->name, port->name, ofproto_port.ofp_port);
+            bridge_ofproto_port_del(br, ofproto_port);
+            ofproto_port_destroy(&ofproto_port);
+        }
+        iface_clear_db_record(iface->cfg);
+        iface_destroy(iface);
+    }
 
-        /* Add bond fake iface if necessary. */
-        if (port_is_bond_fake_iface(port)) {
-            if (ofproto_port_query_by_name(br->ofproto, port->name,
-                                           &ofproto_port)) {
-                struct netdev *netdev;
-                int error;
-
-                error = netdev_open(port->name, "internal", &netdev);
-                if (!error) {
-                    /* There are unlikely to be a great number of fake
-                     * interfaces so we don't bother rate limiting their
-                     * creation. */
-                    ofproto_port_add(br->ofproto, netdev, NULL);
-                    netdev_close(netdev);
-                } else {
-                    VLOG_WARN("could not open network device %s (%s)",
-                              port->name, strerror(error));
-                }
+    if (list_is_empty(&port->ifaces)) {
+        port_destroy(port);
+        return;
+    }
+
+    /* Add bond fake iface if necessary. */
+    if (port_is_bond_fake_iface(port)) {
+        if (ofproto_port_query_by_name(br->ofproto, port->name,
+                                       &ofproto_port)) {
+            struct netdev *netdev;
+            int error;
+
+            error = netdev_open(port->name, "internal", &netdev);
+            if (!error) {
+                ofproto_port_add(br->ofproto, netdev, NULL);
+                netdev_close(netdev);
             } else {
-                /* Already exists, nothing to do. */
-                ofproto_port_destroy(&ofproto_port);
+                VLOG_WARN("could not open network device %s (%s)",
+                          port->name, strerror(error));
             }
+        } else {
+            /* Already exists, nothing to do. */
+            ofproto_port_destroy(&ofproto_port);
         }
     }
 }
@@ -1929,26 +1991,31 @@ bridge_run_fast(void)
 void
 bridge_run(void)
 {
+    static const struct ovsrec_open_vswitch null_cfg;
     const struct ovsrec_open_vswitch *cfg;
+    struct ovsdb_idl_txn *reconf_txn = NULL;
 
     bool vlan_splinters_changed;
     struct bridge *br;
 
     /* (Re)configure if necessary. */
-    ovsdb_idl_run(idl);
-    if (ovsdb_idl_is_lock_contended(idl)) {
-        static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1);
-        struct bridge *br, *next_br;
+    if (!reconfiguring) {
+        ovsdb_idl_run(idl);
 
-        VLOG_ERR_RL(&rl, "another ovs-vswitchd process is running, "
-                    "disabling this process until it goes away");
+        if (ovsdb_idl_is_lock_contended(idl)) {
+            static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1);
+            struct bridge *br, *next_br;
 
-        HMAP_FOR_EACH_SAFE (br, next_br, node, &all_bridges) {
-            bridge_destroy(br);
+            VLOG_ERR_RL(&rl, "another ovs-vswitchd process is running, "
+                        "disabling this process until it goes away");
+
+            HMAP_FOR_EACH_SAFE (br, next_br, node, &all_bridges) {
+                bridge_destroy(br);
+            }
+            return;
+        } else if (!ovsdb_idl_has_lock(idl)) {
+            return;
         }
-        return;
-    } else if (!ovsdb_idl_has_lock(idl)) {
-        return;
     }
     cfg = ovsrec_open_vswitch_first(idl);
 
@@ -1970,38 +2037,51 @@ bridge_run(void)
         stream_ssl_set_ca_cert_file(ssl->ca_cert, ssl->bootstrap_ca_cert);
     }
 
-    /* If VLAN splinters are in use, then we need to reconfigure if VLAN usage
-     * has changed. */
-    vlan_splinters_changed = false;
-    if (vlan_splinters_enabled_anywhere) {
-        HMAP_FOR_EACH (br, node, &all_bridges) {
-            if (ofproto_has_vlan_usage_changed(br->ofproto)) {
-                vlan_splinters_changed = true;
-                break;
+    if (!reconfiguring) {
+        /* If VLAN splinters are in use, then we need to reconfigure if VLAN
+         * usage has changed. */
+        vlan_splinters_changed = false;
+        if (vlan_splinters_enabled_anywhere) {
+            HMAP_FOR_EACH (br, node, &all_bridges) {
+                if (ofproto_has_vlan_usage_changed(br->ofproto)) {
+                    vlan_splinters_changed = true;
+                    break;
+                }
+            }
+        }
+
+        if (ovsdb_idl_get_seqno(idl) != idl_seqno || vlan_splinters_changed) {
+            idl_seqno = ovsdb_idl_get_seqno(idl);
+            if (cfg) {
+                reconf_txn = ovsdb_idl_txn_create(idl);
+                bridge_reconfigure(cfg);
+            } else {
+                /* We still need to reconfigure to avoid dangling pointers to
+                 * now-destroyed ovsrec structures inside bridge data. */
+                bridge_reconfigure(&null_cfg);
             }
         }
     }
 
-    if (need_reconfigure || ovsdb_idl_get_seqno(idl) != idl_seqno
-        || vlan_splinters_changed) {
-        idl_seqno = ovsdb_idl_get_seqno(idl);
+    if (reconfiguring) {
         if (cfg) {
-            struct ovsdb_idl_txn *txn = ovsdb_idl_txn_create(idl);
-
-            bridge_reconfigure(cfg);
-
-            ovsrec_open_vswitch_set_cur_cfg(cfg, cfg->next_cfg);
-            ovsdb_idl_txn_commit(txn);
-            ovsdb_idl_txn_destroy(txn); /* XXX */
+            if (!reconf_txn) {
+                reconf_txn = ovsdb_idl_txn_create(idl);
+            }
+            if (bridge_reconfigure_continue(cfg)) {
+                ovsrec_open_vswitch_set_cur_cfg(cfg, cfg->next_cfg);
+            }
         } else {
-            /* We still need to reconfigure to avoid dangling pointers to
-             * now-destroyed ovsrec structures inside bridge data. */
-            static const struct ovsrec_open_vswitch null_cfg;
-
-            bridge_reconfigure(&null_cfg);
+            bridge_reconfigure_continue(&null_cfg);
         }
     }
 
+    if (reconf_txn) {
+        ovsdb_idl_txn_commit(reconf_txn);
+        ovsdb_idl_txn_destroy(reconf_txn);
+        reconf_txn = NULL;
+    }
+
     /* Refresh system and interface stats if necessary. */
     if (time_msec() >= stats_timer) {
         if (cfg) {
@@ -2089,7 +2169,7 @@ bridge_wait(void)
 {
     ovsdb_idl_wait(idl);
 
-    if (need_reconfigure) {
+    if (reconfiguring) {
         poll_immediate_wake();
     }
 
@@ -2223,6 +2303,9 @@ bridge_create(const struct ovsrec_bridge *br_cfg)
     hmap_init(&br->iface_by_name);
     hmap_init(&br->mirrors);
 
+    hmap_init(&br->if_cfg_todo);
+    list_init(&br->ofpp_garbage);
+
     hmap_insert(&all_bridges, &br->node, hash_string(br->name, 0));
 }
 
@@ -2232,6 +2315,8 @@ bridge_destroy(struct bridge *br)
     if (br) {
         struct mirror *mirror, *next_mirror;
         struct port *port, *next_port;
+        struct if_cfg *if_cfg, *next_if_cfg;
+        struct ofpp_garbage *garbage, *next_garbage;
 
         HMAP_FOR_EACH_SAFE (port, next_port, hmap_node, &br->ports) {
             port_destroy(port);
@@ -2239,12 +2324,23 @@ bridge_destroy(struct bridge *br)
         HMAP_FOR_EACH_SAFE (mirror, next_mirror, hmap_node, &br->mirrors) {
             mirror_destroy(mirror);
         }
+        HMAP_FOR_EACH_SAFE (if_cfg, next_if_cfg, hmap_node, &br->if_cfg_todo) {
+            hmap_remove(&br->if_cfg_todo, &if_cfg->hmap_node);
+            free(if_cfg);
+        }
+        LIST_FOR_EACH_SAFE (garbage, next_garbage, list_node,
+                            &br->ofpp_garbage) {
+            list_remove(&garbage->list_node);
+            free(garbage);
+        }
+
         hmap_remove(&all_bridges, &br->node);
         ofproto_destroy(br->ofproto);
         hmap_destroy(&br->ifaces);
         hmap_destroy(&br->ports);
         hmap_destroy(&br->iface_by_name);
         hmap_destroy(&br->mirrors);
+        hmap_destroy(&br->if_cfg_todo);
         free(br->name);
         free(br->type);
         free(br);
@@ -2330,17 +2426,33 @@ bridge_get_controllers(const struct bridge *br,
     return n_controllers;
 }
 
-/* Adds and deletes "struct port"s and "struct iface"s under 'br' to match
- * those configured in 'br->cfg'. */
+static void
+bridge_queue_if_cfg(struct bridge *br,
+                    const struct ovsrec_interface *cfg,
+                    const struct ovsrec_port *parent)
+{
+    struct if_cfg *if_cfg = xmalloc(sizeof *if_cfg);
+
+    if_cfg->cfg = cfg;
+    if_cfg->parent = parent;
+    hmap_insert(&br->if_cfg_todo, &if_cfg->hmap_node,
+                hash_string(if_cfg->cfg->name, 0));
+}
+
+/* Deletes "struct port"s and "struct iface"s under 'br' which aren't
+ * consistent with 'br->cfg'.  Updates 'br->if_cfg_queue' with interfaces which
+ * 'br' needs to complete its configuration. */
 static void
 bridge_add_del_ports(struct bridge *br,
                      const unsigned long int *splinter_vlans)
 {
+    struct shash_node *port_node;
     struct port *port, *next;
-    struct shash_node *node;
     struct shash new_ports;
     size_t i;
 
+    assert(hmap_is_empty(&br->if_cfg_todo));
+
     /* Collect new ports. */
     shash_init(&new_ports);
     for (i = 0; i < br->cfg->n_ports; i++) {
@@ -2382,21 +2494,23 @@ bridge_add_del_ports(struct bridge *br,
         }
     }
 
-    /* Create new ports.
-     * Add new interfaces to existing ports. */
-    SHASH_FOR_EACH (node, &new_ports) {
-        struct port *port = port_lookup(br, node->name);
-        if (!port) {
-            struct ovsrec_port *cfg = node->data;
-            port = port_create(br, cfg);
-        }
-        port_add_ifaces(port);
-        if (list_is_empty(&port->ifaces)) {
-            VLOG_WARN("bridge %s: port %s has no interfaces, dropping",
-                      br->name, port->name);
-            port_destroy(port);
+    SHASH_FOR_EACH (port_node, &new_ports) {
+        const struct ovsrec_port *port = port_node->data;
+        size_t i;
+
+        for (i = 0; i < port->n_interfaces; i++) {
+            const struct ovsrec_interface *cfg = port->interfaces[i];
+            struct iface *iface = iface_lookup(br, cfg->name);
+
+            if (iface) {
+                iface->cfg = cfg;
+                iface_refresh_type(iface);
+            } else {
+                bridge_queue_if_cfg(br, cfg, port);
+            }
         }
     }
+
     shash_destroy(&new_ports);
 }
 
@@ -2718,51 +2832,6 @@ port_del_ifaces(struct port *port)
     sset_destroy(&new_ifaces);
 }
 
-/* Adds new interfaces to 'port' and updates 'type' and 'cfg' members of
- * existing ones. */
-static void
-port_add_ifaces(struct port *port)
-{
-    struct shash new_ifaces;
-    struct shash_node *node;
-    size_t i;
-
-    /* Collect new ifaces. */
-    shash_init(&new_ifaces);
-    for (i = 0; i < port->cfg->n_interfaces; i++) {
-        const struct ovsrec_interface *cfg = port->cfg->interfaces[i];
-        if (strcmp(cfg->type, "null")
-            && !shash_add_once(&new_ifaces, cfg->name, cfg)) {
-            VLOG_WARN("port %s: %s specified twice as port interface",
-                      port->name, cfg->name);
-            iface_clear_db_record(cfg);
-        }
-    }
-
-    /* Create new interfaces.
-     * Update interface types and 'cfg' members. */
-    SHASH_FOR_EACH (node, &new_ifaces) {
-        const struct ovsrec_interface *cfg = node->data;
-        const char *iface_name = node->name;
-        struct iface *iface;
-
-        iface = iface_lookup(port->bridge, iface_name);
-        if (!iface) {
-            iface = iface_create(port, cfg);
-        } else {
-            iface->cfg = cfg;
-        }
-
-        /* Determine interface type.  The local port always has type
-         * "internal".  Other ports take their type from the database and
-         * default to "system" if none is specified. */
-        iface->type = (!strcmp(iface_name, port->bridge->name) ? "internal"
-                       : cfg->type[0] ? cfg->type
-                       : "system");
-    }
-    shash_destroy(&new_ifaces);
-}
-
 static void
 port_destroy(struct port *port)
 {
@@ -2991,28 +3060,15 @@ port_is_synthetic(const struct port *port)
 \f
 /* Interface functions. */
 
-static struct iface *
-iface_create(struct port *port, const struct ovsrec_interface *if_cfg)
+static void
+iface_refresh_type(struct iface *iface)
 {
-    struct bridge *br = port->bridge;
-    struct iface *iface;
-    char *name = if_cfg->name;
-
-    iface = xzalloc(sizeof *iface);
-    iface->port = port;
-    iface->name = xstrdup(name);
-    iface->ofp_port = -1;
-    iface->netdev = NULL;
-    iface->cfg = if_cfg;
-    iface->need_refresh = true;
-
-    hmap_insert(&br->iface_by_name, &iface->name_node, hash_string(name, 0));
-
-    list_push_back(&port->ifaces, &iface->port_elem);
-
-    VLOG_DBG("attached network device %s to port %s", iface->name, port->name);
-
-    return iface;
+    /* Determine interface type.  The local port always has type
+     * "internal".  Other ports take their type from the database and
+     * default to "system" if none is specified. */
+    iface->type = (!strcmp(iface->name, iface->port->bridge->name) ? "internal"
+                   : iface->cfg->type[0] ? iface->cfg->type
+                   : "system");
 }
 
 static void
@@ -3070,6 +3126,21 @@ iface_find(const char *name)
     return NULL;
 }
 
+static struct if_cfg *
+if_cfg_lookup(const struct bridge *br, const char *name)
+{
+    struct if_cfg *if_cfg;
+
+    HMAP_FOR_EACH_WITH_HASH (if_cfg, hmap_node, hash_string(name, 0),
+                             &br->if_cfg_todo) {
+        if (!strcmp(if_cfg->cfg->name, name)) {
+            return if_cfg;
+        }
+    }
+
+    return NULL;
+}
+
 static struct iface *
 iface_from_ofp_port(const struct bridge *br, uint16_t ofp_port)
 {