[ovs-dev,v10] northd: Add bfd, static_routes, route_policies and bfd_sync nodes to I-P engine.

Introduce bfd, static_routes, route_policies and bfd_sync nodes to northd I-P
engine to track bfd connections and northd static_route/policy_route
changes.

Reported-at: https://issues.redhat.com/browse/FDP-600
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
---
Changes since v9:
- write in I-P private data just in the corresponding I-P node
- move lr_port lookup in bfd_table_sync()
- cosmetics
Changes since v8:
- rebase on top of ovn main branch and fix conflicts
Changes since v7:
- rework node dependencies and move all NB-BFD table update in bfd_sync node
- fix some more comments
Changes since v6:
- remove unnecessary node inputs
- fix comment
Changes since v5:
- remove bfd_mutex
Changes since v4:
- introduce bfd_nb_sync node and ger rid of bfd_consumer routine
Changes since v3:
- fix bfd_northd_change_handler logic
- fix route_policies_northd_change_handler logic
- fix static_routes_northd_change_handler logic
- add unit-tests
- cosmetics
Changes since v2:
- add incremental processing routines
- split bfd_consumer node in static_routes and route_policies nodes
Changes since v1:
- add incremental processing logic for bfd_consumer node to avoid a full
  recompute
---
 northd/en-lflow.c        |  25 +-
 northd/en-northd.c       | 224 ++++++++++++
 northd/en-northd.h       |  23 ++
 northd/inc-proc-northd.c |  27 +-
 northd/northd.c          | 722 +++++++++++++++++++++++++++------------
 northd/northd.h          |  72 +++-
 tests/ovn-northd.at      |  56 +++
 7 files changed, 911 insertions(+), 238 deletions(-)

On Wed, Jul 31, 2024 at 1:32 PM Lorenzo Bianconi
<lorenzo.bianconi@redhat.com> wrote:
>
> Introduce bfd, static_routes, route_policies and bfd_sync nodes to northd I-P
> engine to track bfd connections and northd static_route/policy_route
> changes.
>
> Reported-at: https://issues.redhat.com/browse/FDP-600
> Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
> ---
> Changes since v9:
> - write in I-P private data just in the corresponding I-P node
> - move lr_port lookup in bfd_table_sync()
> - cosmetics
> Changes since v8:
> - rebase on top of ovn main branch and fix conflicts
> Changes since v7:
> - rework node dependencies and move all NB-BFD table update in bfd_sync node
> - fix some more comments
> Changes since v6:
> - remove unnecessary node inputs
> - fix comment
> Changes since v5:
> - remove bfd_mutex
> Changes since v4:
> - introduce bfd_nb_sync node and ger rid of bfd_consumer routine
> Changes since v3:
> - fix bfd_northd_change_handler logic
> - fix route_policies_northd_change_handler logic
> - fix static_routes_northd_change_handler logic
> - add unit-tests
> - cosmetics
> Changes since v2:
> - add incremental processing routines
> - split bfd_consumer node in static_routes and route_policies nodes
> Changes since v1:
> - add incremental processing logic for bfd_consumer node to avoid a full
>   recompute
> ---
>  northd/en-lflow.c        |  25 +-
>  northd/en-northd.c       | 224 ++++++++++++
>  northd/en-northd.h       |  23 ++
>  northd/inc-proc-northd.c |  27 +-
>  northd/northd.c          | 722 +++++++++++++++++++++++++++------------
>  northd/northd.h          |  72 +++-
>  tests/ovn-northd.at      |  56 +++
>  7 files changed, 911 insertions(+), 238 deletions(-)
>
> diff --git a/northd/en-lflow.c b/northd/en-lflow.c
> index c4b927fb8..3dba5034b 100644
> --- a/northd/en-lflow.c
> +++ b/northd/en-lflow.c
> @@ -41,6 +41,11 @@ lflow_get_input_data(struct engine_node *node,
>                       struct lflow_input *lflow_input)
>  {
>      struct northd_data *northd_data = engine_get_input_data("northd", node);
> +    struct bfd_data *bfd_data = engine_get_input_data("bfd", node);
> +    struct static_routes_data *static_routes_data =
> +        engine_get_input_data("static_routes", node);
> +    struct route_policies_data *route_policies_data =
> +        engine_get_input_data("route_policies", node);
>      struct port_group_data *pg_data =
>          engine_get_input_data("port_group", node);
>      struct sync_meters_data *sync_meters_data =
> @@ -50,10 +55,6 @@ lflow_get_input_data(struct engine_node *node,
>      struct ed_type_ls_stateful *ls_stateful_data =
>          engine_get_input_data("ls_stateful", node);
>
> -    lflow_input->nbrec_bfd_table =
> -        EN_OVSDB_GET(engine_get_input("NB_bfd", node));
> -    lflow_input->sbrec_bfd_table =
> -        EN_OVSDB_GET(engine_get_input("SB_bfd", node));
>      lflow_input->sbrec_logical_flow_table =
>          EN_OVSDB_GET(engine_get_input("SB_logical_flow", node));
>      lflow_input->sbrec_multicast_group_table =
> @@ -78,7 +79,10 @@ lflow_get_input_data(struct engine_node *node,
>      lflow_input->meter_groups = &sync_meters_data->meter_groups;
>      lflow_input->lb_datapaths_map = &northd_data->lb_datapaths_map;
>      lflow_input->svc_monitor_map = &northd_data->svc_monitor_map;
> -    lflow_input->bfd_connections = NULL;
> +    lflow_input->bfd_connections = &bfd_data->bfd_connections;
> +    lflow_input->parsed_routes = &static_routes_data->parsed_routes;
> +    lflow_input->route_tables = &static_routes_data->route_tables;
> +    lflow_input->route_policies = &route_policies_data->route_policies;
>
>      struct ed_type_global_config *global_config =
>          engine_get_input_data("global_config", node);
> @@ -95,25 +99,14 @@ void en_lflow_run(struct engine_node *node, void *data)
>      struct lflow_input lflow_input;
>      lflow_get_input_data(node, &lflow_input);
>
> -    struct hmap bfd_connections = HMAP_INITIALIZER(&bfd_connections);
> -    lflow_input.bfd_connections = &bfd_connections;
> -
>      stopwatch_start(BUILD_LFLOWS_STOPWATCH_NAME, time_msec());
>
>      struct lflow_data *lflow_data = data;
>      lflow_table_clear(lflow_data->lflow_table);
>      lflow_reset_northd_refs(&lflow_input);
>
> -    build_bfd_table(eng_ctx->ovnsb_idl_txn,
> -                    lflow_input.nbrec_bfd_table,
> -                    lflow_input.sbrec_bfd_table,
> -                    lflow_input.lr_ports,
> -                    &bfd_connections);
>      build_lflows(eng_ctx->ovnsb_idl_txn, &lflow_input,
>                   lflow_data->lflow_table);
> -    bfd_cleanup_connections(lflow_input.nbrec_bfd_table,
> -                            &bfd_connections);
> -    hmap_destroy(&bfd_connections);
>      stopwatch_stop(BUILD_LFLOWS_STOPWATCH_NAME, time_msec());
>
>      engine_set_node_state(node, EN_UPDATED);
> diff --git a/northd/en-northd.c b/northd/en-northd.c
> index 4479b4aff..63cb8edbf 100644
> --- a/northd/en-northd.c
> +++ b/northd/en-northd.c
> @@ -236,6 +236,171 @@ northd_global_config_handler(struct engine_node *node, void *data OVS_UNUSED)
>      return true;
>  }
>
> +bool
> +route_policies_northd_change_handler(struct engine_node *node,
> +                                     void *data OVS_UNUSED)
> +{
> +    struct northd_data *northd_data = engine_get_input_data("northd", node);
> +    if (!northd_has_tracked_data(&northd_data->trk_data)) {
> +        return false;
> +    }
> +
> +    /* This node uses the below data from the en_northd engine node.
> +     * See (lr_stateful_get_input_data())
> +     *   1. northd_data->lr_datapaths
> +     *   2. northd_data->lr_ports
> +     *      This data gets updated when a logical router or logical router port
> +     *      is created or deleted.
> +     *      Northd engine node presently falls back to full recompute when
> +     *      this happens and so does this node.
> +     *      Note: When we add I-P to the created/deleted logical routers or
> +     *      logical router ports, we need to revisit this handler.
> +     *
> +     *      This node also accesses the route policies of the logical router.
> +     *      When these route policies get updated, en_northd engine recomputes
> +     *      and so does this node.
> +     *      Note: When we add I-P to handle route policies changes, we need
> +     *      to revisit this handler.
> +     */
> +    return true;
> +}
> +
> +void
> +en_route_policies_run(struct engine_node *node, void *data)
> +{
> +    struct northd_data *northd_data = engine_get_input_data("northd", node);
> +    struct bfd_data *bfd_data = engine_get_input_data("bfd", node);
> +    struct route_policies_data *route_policies_data = data;
> +
> +    route_policies_destroy(data);
> +    route_policies_init(data);
> +
> +    struct ovn_datapath *od;
> +    HMAP_FOR_EACH (od, key_node, &northd_data->lr_datapaths.datapaths) {
> +        build_route_policies(od, &northd_data->lr_ports,
> +                             &bfd_data->bfd_connections,
> +                             &route_policies_data->route_policies,
> +                             &route_policies_data->bfd_active_connections);
> +    }
> +
> +    engine_set_node_state(node, EN_UPDATED);
> +}
> +
> +bool
> +static_routes_northd_change_handler(struct engine_node *node,
> +                                    void *data OVS_UNUSED)
> +{
> +    struct northd_data *northd_data = engine_get_input_data("northd", node);
> +    if (!northd_has_tracked_data(&northd_data->trk_data)) {
> +        return false;
> +    }
> +
> +    /* This node uses the below data from the en_northd engine node.
> +     * See (lr_stateful_get_input_data())
> +     *   1. northd_data->lr_datapaths
> +     *   2. northd_data->lr_ports
> +     *      This data gets updated when a logical router or logical router port
> +     *      is created or deleted.
> +     *      Northd engine node presently falls back to full recompute when
> +     *      this happens and so does this node.
> +     *      Note: When we add I-P to the created/deleted logical routers or
> +     *      logical router ports, we need to revisit this handler.
> +     *
> +     *      This node also accesses the static routes of the logical router.
> +     *      When these static routes gets updated, en_northd engine recomputes
> +     *      and so does this node.
> +     *      Note: When we add I-P to handle static routes changes, we need
> +     *      to revisit this handler.
> +     */
> +    return true;
> +}
> +
> +void
> +en_static_routes_run(struct engine_node *node, void *data)
> +{
> +    struct northd_data *northd_data = engine_get_input_data("northd", node);
> +    struct bfd_data *bfd_data = engine_get_input_data("bfd", node);
> +    struct static_routes_data *static_routes_data = data;
> +
> +    static_routes_destroy(data);
> +    static_routes_init(data);
> +
> +    struct ovn_datapath *od;
> +    HMAP_FOR_EACH (od, key_node, &northd_data->lr_datapaths.datapaths) {
> +        for (int i = 0; i < od->nbr->n_ports; i++) {
> +            const char *route_table_name =
> +                smap_get(&od->nbr->ports[i]->options, "route_table");
> +            get_route_table_id(&static_routes_data->route_tables,
> +                               route_table_name);
> +        }
> +
> +        build_parsed_routes(od, &northd_data->lr_ports,
> +                            &bfd_data->bfd_connections,
> +                            &static_routes_data->parsed_routes,
> +                            &static_routes_data->route_tables,
> +                            &static_routes_data->bfd_active_connections);
> +    }
> +
> +    engine_set_node_state(node, EN_UPDATED);
> +}
> +
> +void
> +en_bfd_run(struct engine_node *node, void *data)
> +{
> +    struct bfd_data *bfd_data = data;
> +    const struct nbrec_bfd_table *nbrec_bfd_table =
> +        EN_OVSDB_GET(engine_get_input("NB_bfd", node));
> +    const struct sbrec_bfd_table *sbrec_bfd_table =
> +        EN_OVSDB_GET(engine_get_input("SB_bfd", node));
> +
> +    bfd_destroy(data);
> +    bfd_init(data);
> +    build_bfd_map(nbrec_bfd_table, sbrec_bfd_table,
> +                  &bfd_data->bfd_connections);
> +    engine_set_node_state(node, EN_UPDATED);
> +}
> +
> +bool
> +bfd_sync_change_handler(struct engine_node *node, void *data OVS_UNUSED)
> +{
> +    struct northd_data *northd_data = engine_get_input_data("northd", node);
> +    if (!northd_has_tracked_data(&northd_data->trk_data)) {
> +        return false;
> +    }
> +
> +    /* This node uses the below data from the en_northd engine node.
> +     * See (lr_stateful_get_input_data())
> +     *   1. northd_data->lr_ports
> +     *      This data gets updated when a logical router port is created or
> +     *      deleted. Northd engine node presently falls back to full recompute
> +     *      when this happens and so does this node.
> +     *      Note: When we add I-P to the created/deleted logical router ports,
> +     *      we need to revisit this handler.
> +     */
> +    return true;
> +}
> +
> +void
> +en_bfd_sync_run(struct engine_node *node OVS_UNUSED,
> +                void *data OVS_UNUSED)
> +{
> +    struct northd_data *northd_data = engine_get_input_data("northd", node);
> +    const struct engine_context *eng_ctx = engine_get_context();
> +    struct bfd_data *bfd_data = engine_get_input_data("bfd", node);
> +    struct route_policies_data *route_policies_data
> +        = engine_get_input_data("route_policies", node);
> +    struct static_routes_data *static_routes_data
> +        = engine_get_input_data("static_routes", node);
> +    const struct nbrec_bfd_table *nbrec_bfd_table =
> +        EN_OVSDB_GET(engine_get_input("NB_bfd", node));
> +
> +    bfd_table_sync(eng_ctx->ovnsb_idl_txn, nbrec_bfd_table,
> +                   &northd_data->lr_ports, &bfd_data->bfd_connections,
> +                   &route_policies_data->bfd_active_connections,
> +                   &static_routes_data->bfd_active_connections);
> +    engine_set_node_state(node, EN_UPDATED);
> +}
> +
>  void
>  *en_northd_init(struct engine_node *node OVS_UNUSED,
>                  struct engine_arg *arg OVS_UNUSED)
> @@ -247,6 +412,42 @@ void
>      return data;
>  }
>
> +void
> +*en_route_policies_init(struct engine_node *node OVS_UNUSED,
> +                        struct engine_arg *arg OVS_UNUSED)
> +{
> +    struct route_policies_data *data = xzalloc(sizeof *data);
> +
> +    route_policies_init(data);
> +    return data;
> +}
> +
> +void
> +*en_static_routes_init(struct engine_node *node OVS_UNUSED,
> +                      struct engine_arg *arg OVS_UNUSED)
> +{
> +    struct static_routes_data *data = xzalloc(sizeof *data);
> +
> +    static_routes_init(data);
> +    return data;
> +}
> +
> +void
> +*en_bfd_init(struct engine_node *node OVS_UNUSED,
> +             struct engine_arg *arg OVS_UNUSED)
> +{
> +    struct bfd_data *data = xzalloc(sizeof *data);
> +
> +    bfd_init(data);
> +    return data;
> +}
> +
> +void *en_bfd_sync_init(struct engine_node *node OVS_UNUSED,
> +                       struct engine_arg *arg OVS_UNUSED)
> +{
> +    return NULL;
> +}
> +
>  void
>  en_northd_cleanup(void *data)
>  {
> @@ -259,3 +460,26 @@ en_northd_clear_tracked_data(void *data_)
>      struct northd_data *data = data_;
>      destroy_northd_data_tracked_changes(data);
>  }
> +
> +void
> +en_route_policies_cleanup(void *data)
> +{
> +    route_policies_destroy(data);
> +}
> +
> +void
> +en_static_routes_cleanup(void *data)
> +{
> +    static_routes_destroy(data);
> +}
> +
> +void
> +en_bfd_cleanup(void *data)
> +{
> +    bfd_destroy(data);
> +}
> +
> +void
> +en_bfd_sync_cleanup(void *data OVS_UNUSED)
> +{
> +}
> diff --git a/northd/en-northd.h b/northd/en-northd.h
> index 9b7bda32a..742bb2509 100644
> --- a/northd/en-northd.h
> +++ b/northd/en-northd.h
> @@ -19,5 +19,28 @@ bool northd_nb_logical_switch_handler(struct engine_node *, void *data);
>  bool northd_nb_logical_router_handler(struct engine_node *, void *data);
>  bool northd_sb_port_binding_handler(struct engine_node *, void *data);
>  bool northd_lb_data_handler(struct engine_node *, void *data);
> +void *en_static_routes_init(struct engine_node *node OVS_UNUSED,
> +                            struct engine_arg *arg OVS_UNUSED);
> +void en_route_policies_cleanup(void *data);
> +bool route_policies_northd_change_handler(struct engine_node *node,
> +                                          void *data OVS_UNUSED);
> +void en_route_policies_run(struct engine_node *node, void *data);
> +void *en_route_policies_init(struct engine_node *node OVS_UNUSED,
> +                             struct engine_arg *arg OVS_UNUSED);
> +void en_static_routes_cleanup(void *data);
> +bool static_routes_northd_change_handler(struct engine_node *node,
> +                                         void *data OVS_UNUSED);
> +void en_static_routes_run(struct engine_node *node, void *data);
> +void *en_bfd_init(struct engine_node *node OVS_UNUSED,
> +                  struct engine_arg *arg OVS_UNUSED);
> +void en_bfd_cleanup(void *data);
> +void en_bfd_run(struct engine_node *node, void *data);
> +void *en_bfd_sync_init(struct engine_node *node OVS_UNUSED,
> +                       struct engine_arg *arg OVS_UNUSED);
> +bool bfd_sync_change_handler(struct engine_node *node,
> +                             void *data OVS_UNUSED);
> +void en_bfd_sync_run(struct engine_node *node OVS_UNUSED,
> +                     void *data OVS_UNUSED);
> +void en_bfd_sync_cleanup(void *data OVS_UNUSED);
>
>  #endif /* EN_NORTHD_H */
> diff --git a/northd/inc-proc-northd.c b/northd/inc-proc-northd.c
> index 522236ad2..f5e3e4880 100644
> --- a/northd/inc-proc-northd.c
> +++ b/northd/inc-proc-northd.c
> @@ -155,6 +155,10 @@ static ENGINE_NODE_WITH_CLEAR_TRACK_DATA(lb_data, "lb_data");
>  static ENGINE_NODE_WITH_CLEAR_TRACK_DATA(lr_nat, "lr_nat");
>  static ENGINE_NODE_WITH_CLEAR_TRACK_DATA(lr_stateful, "lr_stateful");
>  static ENGINE_NODE_WITH_CLEAR_TRACK_DATA(ls_stateful, "ls_stateful");
> +static ENGINE_NODE(route_policies, "route_policies");
> +static ENGINE_NODE(static_routes, "static_routes");
> +static ENGINE_NODE(bfd, "bfd");
> +static ENGINE_NODE(bfd_sync, "bfd_sync");
>
>  void inc_proc_northd_init(struct ovsdb_idl_loop *nb,
>                            struct ovsdb_idl_loop *sb)
> @@ -237,18 +241,37 @@ void inc_proc_northd_init(struct ovsdb_idl_loop *nb,
>      engine_add_input(&en_fdb_aging, &en_global_config,
>                       node_global_config_handler);
>
> +    engine_add_input(&en_bfd, &en_nb_bfd, NULL);
> +    engine_add_input(&en_bfd, &en_sb_bfd, NULL);
> +
> +    engine_add_input(&en_route_policies, &en_bfd, NULL);
> +    engine_add_input(&en_route_policies, &en_northd,
> +                     route_policies_northd_change_handler);
> +
> +    engine_add_input(&en_static_routes, &en_bfd, NULL);
> +    engine_add_input(&en_static_routes, &en_northd,
> +                     static_routes_northd_change_handler);
> +
> +    engine_add_input(&en_bfd_sync, &en_bfd, NULL);
> +    engine_add_input(&en_bfd_sync, &en_nb_bfd, NULL);
> +    engine_add_input(&en_bfd_sync, &en_static_routes, NULL);
> +    engine_add_input(&en_bfd_sync, &en_route_policies, NULL);
> +    engine_add_input(&en_bfd_sync, &en_northd, bfd_sync_change_handler);

nit: The change handler naming convention is
<node>_<input>_change_handler, so it should be
bfd_sync_northd_change_handler.

> +
>      engine_add_input(&en_sync_meters, &en_nb_acl, NULL);
>      engine_add_input(&en_sync_meters, &en_nb_meter, NULL);
>      engine_add_input(&en_sync_meters, &en_sb_meter, NULL);
>
> -    engine_add_input(&en_lflow, &en_nb_bfd, NULL);
>      engine_add_input(&en_lflow, &en_nb_acl, NULL);
>      engine_add_input(&en_lflow, &en_sync_meters, NULL);
> -    engine_add_input(&en_lflow, &en_sb_bfd, NULL);
>      engine_add_input(&en_lflow, &en_sb_logical_flow, NULL);
>      engine_add_input(&en_lflow, &en_sb_multicast_group, NULL);
>      engine_add_input(&en_lflow, &en_sb_igmp_group, NULL);
>      engine_add_input(&en_lflow, &en_sb_logical_dp_group, NULL);
> +    engine_add_input(&en_lflow, &en_bfd, NULL);
> +    engine_add_input(&en_lflow, &en_bfd_sync, NULL);

I guess the reason why this input is required here is because there is
a hidden dependency: the bfd_sync node updates lr_ports op->has_bfd
field, and the en_lflow node depends on this field. If this is the
case, could you at least add a comment here to call out as a tech debt
so that it can be addressed in the future, if not now?

> +    engine_add_input(&en_lflow, &en_route_policies, NULL);
> +    engine_add_input(&en_lflow, &en_static_routes, NULL);
>      engine_add_input(&en_lflow, &en_global_config,
>                       node_global_config_handler);
>      engine_add_input(&en_lflow, &en_northd, lflow_northd_handler);
> diff --git a/northd/northd.c b/northd/northd.c
> index a8a0b6f94..dad8d4069 100644
> --- a/northd/northd.c
> +++ b/northd/northd.c
> @@ -9702,11 +9702,47 @@ build_lswitch_ip_unicast_lookup_for_nats(
>  struct bfd_entry {
>      struct hmap_node hmap_node;
>
> +    const struct nbrec_bfd *nb_bt;
>      const struct sbrec_bfd *sb_bt;
>
> -    bool ref;
> +    char *logical_port;
> +    char *dst_ip;
> +    char *status;
> +    bool stale;
>  };
>
> +static struct bfd_entry *
> +bfd_alloc_entry(struct hmap *bfd_connections,
> +                const char *logical_port, const char *dst_ip,
> +                const char *status)
> +{
> +    struct bfd_entry *bfd_e = xzalloc(sizeof *bfd_e);
> +    bfd_e->logical_port = xstrdup(logical_port);
> +    bfd_e->dst_ip = xstrdup(dst_ip);
> +    bfd_e->status = xstrdup(status);
> +    uint32_t hash = hash_string(dst_ip, 0);
> +    hash = hash_string(logical_port, hash);
> +    hmap_insert(bfd_connections, &bfd_e->hmap_node, hash);
> +
> +    return bfd_e;
> +}
> +
> +static void
> +bfd_erase_entry(struct bfd_entry *bfd_e)
> +{
> +    free(bfd_e->logical_port);
> +    free(bfd_e->dst_ip);
> +    free(bfd_e->status);
> +    free(bfd_e);
> +}
> +
> +static void
> +bfd_set_status(struct bfd_entry *bfd_e, const char *status)
> +{
> +    free(bfd_e->status);
> +    bfd_e->status = xstrdup(status);
> +}
> +
>  static struct bfd_entry *
>  bfd_port_lookup(const struct hmap *bfd_map, const char *logical_port,
>                  const char *dst_ip)
> @@ -9717,36 +9753,13 @@ bfd_port_lookup(const struct hmap *bfd_map, const char *logical_port,
>      hash = hash_string(dst_ip, 0);
>      hash = hash_string(logical_port, hash);
>      HMAP_FOR_EACH_WITH_HASH (bfd_e, hmap_node, hash, bfd_map) {
> -        if (!strcmp(bfd_e->sb_bt->logical_port, logical_port) &&
> -            !strcmp(bfd_e->sb_bt->dst_ip, dst_ip)) {
> +        if (!strcmp(bfd_e->logical_port, logical_port) &&
> +            !strcmp(bfd_e->dst_ip, dst_ip)) {
>              return bfd_e;
>          }
>      }
> -    return NULL;
> -}
> -
> -void
> -bfd_cleanup_connections(const struct nbrec_bfd_table *nbrec_bfd_table,
> -                        struct hmap *bfd_map)
> -{
> -    const struct nbrec_bfd *nb_bt;
> -    struct bfd_entry *bfd_e;
> -
> -    NBREC_BFD_TABLE_FOR_EACH (nb_bt, nbrec_bfd_table) {
> -        bfd_e = bfd_port_lookup(bfd_map, nb_bt->logical_port, nb_bt->dst_ip);
> -        if (!bfd_e) {
> -            continue;
> -        }
> -
> -        if (!bfd_e->ref && strcmp(nb_bt->status, "admin_down")) {
> -            /* no user for this bfd connection */
> -            nbrec_bfd_set_status(nb_bt, "admin_down");
> -        }
> -    }
>
> -    HMAP_FOR_EACH_POP (bfd_e, hmap_node, bfd_map) {
> -        free(bfd_e);
> -    }
> +    return NULL;
>  }
>
>  #define BFD_DEF_MINTX       1000 /* 1s */
> @@ -9809,51 +9822,90 @@ static int bfd_get_unused_port(unsigned long *bfd_src_ports)
>      return port + BFD_UDP_SRC_PORT_START;
>  }
>
> -void
> -build_bfd_table(struct ovsdb_idl_txn *ovnsb_txn,
> -                const struct nbrec_bfd_table *nbrec_bfd_table,
> -                const struct sbrec_bfd_table *sbrec_bfd_table,
> -                const struct hmap *lr_ports, struct hmap *bfd_connections)
> +static char *
> +bfd_get_connection_status(const struct nbrec_bfd *nb_bt,
> +                          struct hmap *rp_bfd_connections,
> +                          struct hmap *sr_bfd_connections)
>  {
> -    struct hmap sb_only = HMAP_INITIALIZER(&sb_only);
> -    const struct sbrec_bfd *sb_bt;
> -    unsigned long *bfd_src_ports;
> -    struct bfd_entry *bfd_e;
> -    uint32_t hash;
> +    struct bfd_entry *bfd_rp, *bfd_sr;
>
> -    bfd_src_ports = bitmap_allocate(BFD_UDP_SRC_PORT_LEN);
> +    bfd_rp = bfd_port_lookup(rp_bfd_connections, nb_bt->logical_port,
> +                             nb_bt->dst_ip);
> +    if (!bfd_rp) {
> +        bfd_sr = bfd_port_lookup(sr_bfd_connections, nb_bt->logical_port,
> +                                 nb_bt->dst_ip);
> +        if (!bfd_sr) {
> +            return "admin_down";
> +        }
> +    }
>
> -    SBREC_BFD_TABLE_FOR_EACH (sb_bt, sbrec_bfd_table) {
> -        bfd_e = xmalloc(sizeof *bfd_e);
> -        bfd_e->sb_bt = sb_bt;
> -        hash = hash_string(sb_bt->dst_ip, 0);
> -        hash = hash_string(sb_bt->logical_port, hash);
> -        hmap_insert(&sb_only, &bfd_e->hmap_node, hash);
> -        bitmap_set1(bfd_src_ports, sb_bt->src_port - BFD_UDP_SRC_PORT_START);
> +    return bfd_rp ? bfd_rp->status : bfd_sr->status;
> +}
> +
> +void
> +bfd_table_sync(struct ovsdb_idl_txn *ovnsb_txn,
> +               const struct nbrec_bfd_table *nbrec_bfd_table,
> +               const struct hmap *lr_ports,
> +               struct hmap *bfd_connections,
> +               struct hmap *rp_bfd_connections,
> +               struct hmap *sr_bfd_connections)
> +{
> +    if (!ovnsb_txn) {
> +        return;
> +    }
> +
> +    unsigned long *bfd_src_ports = bitmap_allocate(BFD_UDP_SRC_PORT_LEN);
> +    struct hmap bfd_map = HMAP_INITIALIZER(&bfd_map);
> +
> +    struct bfd_entry *bfd_e;
> +    HMAP_FOR_EACH (bfd_e, hmap_node, bfd_connections) {
> +        /* Make a private copy of bfd_connections map in orther to allow
> +         * writing into map entries. */

I think this comment is a little misleading. In this function we don't
really need to write anything to the bfd_connections or even the
bfd_map. The bfd_map is temporary and its only purpose is to record
the stale entries so that they can be handled at the end of this
function. The only field that is updated is the "stale". I think the
"stale" field can be removed from the structure. We can instead do
something similar but slightly more efficient here. We still need a
temporary hmap, and initialized here by copying the whole
bfd_connections entries. But in the next loop NBREC_BFD_TABLE_FOR_EACH
we remove the entry because it is not stale. In the last loop it will
only contain stale entries that need to be handled, so there is no
need to maintain the "stale" status. What do you think?

Thanks,
Han

> +        struct bfd_entry *e = bfd_alloc_entry(&bfd_map, bfd_e->logical_port,
> +                                              bfd_e->dst_ip, bfd_e->status);
> +        e->stale = true;
> +        e->nb_bt = bfd_e->nb_bt;
> +        e->sb_bt = bfd_e->sb_bt;
> +
> +        /* we need to check if this entry is even in the BFD nb db table */
> +        if (bfd_e->sb_bt) {
> +            bitmap_set1(bfd_src_ports,
> +                        bfd_e->sb_bt->src_port - BFD_UDP_SRC_PORT_START);
> +        }
>      }
>
>      const struct nbrec_bfd *nb_bt;
>      NBREC_BFD_TABLE_FOR_EACH (nb_bt, nbrec_bfd_table) {
> -        if (!nb_bt->status) {
> -            /* default state is admin_down */
> -            nbrec_bfd_set_status(nb_bt, "admin_down");
> +        bfd_e = bfd_port_lookup(&bfd_map, nb_bt->logical_port, nb_bt->dst_ip);
> +        if (!bfd_e) {
> +            continue;
>          }
>
>          struct ovn_port *op = ovn_port_find(lr_ports, nb_bt->logical_port);
> -        bfd_e = bfd_port_lookup(&sb_only, nb_bt->logical_port, nb_bt->dst_ip);
> -        if (!bfd_e) {
> +        if (!op || !op->sb) {
> +            /* skip not bounded ports */
> +            continue;
> +        }
> +        op->has_bfd = true;
> +
> +        nbrec_bfd_set_status(nb_bt,
> +                             bfd_get_connection_status(nb_bt,
> +                                                       rp_bfd_connections,
> +                                                       sr_bfd_connections));
> +        if (!bfd_e->sb_bt) {
>              int udp_src = bfd_get_unused_port(bfd_src_ports);
>              if (udp_src < 0) {
>                  continue;
>              }
>
> -            sb_bt = sbrec_bfd_insert(ovnsb_txn);
> +            /* Add entry to bfd sb table. */
> +            const struct sbrec_bfd *sb_bt = sbrec_bfd_insert(ovnsb_txn);
>              sbrec_bfd_set_logical_port(sb_bt, nb_bt->logical_port);
>              sbrec_bfd_set_dst_ip(sb_bt, nb_bt->dst_ip);
>              sbrec_bfd_set_disc(sb_bt, 1 + random_uint32());
>              sbrec_bfd_set_src_port(sb_bt, udp_src);
>              sbrec_bfd_set_status(sb_bt, nb_bt->status);
> -            if (op && op->sb && op->sb->chassis) {
> +            if (op->sb->chassis) {
>                  sbrec_bfd_set_chassis_name(sb_bt, op->sb->chassis->name);
>              }
>
> @@ -9873,37 +9925,62 @@ build_bfd_table(struct ovsdb_idl_txn *ovnsb_txn,
>                      nbrec_bfd_set_status(nb_bt, bfd_e->sb_bt->status);
>                  }
>              }
> +
>              build_bfd_update_sb_conf(nb_bt, bfd_e->sb_bt);
> -            if (op && op->sb && op->sb->chassis &&
> -                strcmp(op->sb->chassis->name, bfd_e->sb_bt->chassis_name)) {
> +            if (op->sb->chassis && !strcmp(op->sb->chassis->name,
> +                                           bfd_e->sb_bt->chassis_name)) {
>                  sbrec_bfd_set_chassis_name(bfd_e->sb_bt,
>                                             op->sb->chassis->name);
>              }
> -
> -            hmap_remove(&sb_only, &bfd_e->hmap_node);
> -            bfd_e->ref = false;
> -            hash = hash_string(bfd_e->sb_bt->dst_ip, 0);
> -            hash = hash_string(bfd_e->sb_bt->logical_port, hash);
> -            hmap_insert(bfd_connections, &bfd_e->hmap_node, hash);
>          }
> +        bfd_e->stale = false;
> +    }
>
> -        if (op) {
> -            op->has_bfd = true;
> +    HMAP_FOR_EACH_POP (bfd_e, hmap_node, &bfd_map) {
> +        if (bfd_e->stale) {
> +            struct ovn_port *op = ovn_port_find(lr_ports, bfd_e->logical_port);
> +            if (op) {
> +                op->has_bfd = false;
> +            }
> +            sbrec_bfd_delete(bfd_e->sb_bt);
>          }
> +        bfd_erase_entry(bfd_e);
>      }
> +    hmap_destroy(&bfd_map);
> +
> +    bitmap_free(bfd_src_ports);
> +}
> +
> +void
> +build_bfd_map(const struct nbrec_bfd_table *nbrec_bfd_table,
> +              const struct sbrec_bfd_table *sbrec_bfd_table,
> +              struct hmap *bfd_connections)
> +{
> +    struct bfd_entry *bfd_e;
>
> -    HMAP_FOR_EACH_POP (bfd_e, hmap_node, &sb_only) {
> -        struct ovn_port *op = ovn_port_find(lr_ports,
> -                                            bfd_e->sb_bt->logical_port);
> -        if (op) {
> -            op->has_bfd = false;
> +    /* align bfd_map to sb db */
> +    const struct sbrec_bfd *sb_bt;
> +    SBREC_BFD_TABLE_FOR_EACH (sb_bt, sbrec_bfd_table) {
> +        bfd_e = bfd_port_lookup(bfd_connections, sb_bt->logical_port,
> +                                sb_bt->dst_ip);
> +        if (!bfd_e) {
> +            bfd_e = bfd_alloc_entry(bfd_connections, sb_bt->logical_port,
> +                                    sb_bt->dst_ip,  sb_bt->status);
>          }
> -        sbrec_bfd_delete(bfd_e->sb_bt);
> -        free(bfd_e);
> +        bfd_e->sb_bt = sb_bt;
>      }
> -    hmap_destroy(&sb_only);
>
> -    bitmap_free(bfd_src_ports);
> +    const struct nbrec_bfd *nb_bt;
> +    NBREC_BFD_TABLE_FOR_EACH (nb_bt, nbrec_bfd_table) {
> +        bfd_e = bfd_port_lookup(bfd_connections, nb_bt->logical_port,
> +                                nb_bt->dst_ip);
> +        if (!bfd_e) {
> +            /* brand new entry. */
> +            bfd_e = bfd_alloc_entry(bfd_connections, nb_bt->logical_port,
> +                                    nb_bt->dst_ip, "admin_down");
> +        }
> +        bfd_e->nb_bt = nb_bt;
> +    }
>  }
>
>  /* Returns a string of the IP address of the router port 'op' that
> @@ -9941,17 +10018,13 @@ get_outport_for_routing_policy_nexthop(struct ovn_datapath *od,
>      return NULL;
>  }
>
> -static struct ovs_mutex bfd_lock = OVS_MUTEX_INITIALIZER;
> -
> -static bool check_bfd_state(
> -        const struct nbrec_logical_router_policy *rule,
> -        const struct hmap *bfd_connections,
> -        struct ovn_port *out_port,
> -        const char *nexthop)
> +static bool check_bfd_state(const struct nbrec_logical_router_policy *rule,
> +                            struct ovn_port *out_port, const char *nexthop,
> +                            struct hmap *bfd_connections,
> +                            struct hmap *bfd_active_connections)
>  {
>      struct in6_addr nexthop_v6;
>      bool is_nexthop_v6 = ipv6_parse(nexthop, &nexthop_v6);
> -    bool ret = true;
>
>      for (size_t i = 0; i < rule->n_bfd_sessions; i++) {
>          /* Check if there is a BFD session associated to the reroute
> @@ -9976,39 +10049,48 @@ static bool check_bfd_state(
>          struct bfd_entry *bfd_e = bfd_port_lookup(bfd_connections,
>                                                    nb_bt->logical_port,
>                                                    nb_bt->dst_ip);
> -        ovs_mutex_lock(&bfd_lock);
> -        if (bfd_e) {
> -            bfd_e->ref = true;
> +        if (!bfd_e) {
> +            continue;
>          }
>
> -        if (!strcmp(nb_bt->status, "admin_down")) {
> -            nbrec_bfd_set_status(nb_bt, "down");
> +        /* This route policy is linked to an active bfd session. */
> +        struct bfd_entry *bfd_rp = bfd_port_lookup(bfd_active_connections,
> +                                                   nb_bt->logical_port,
> +                                                   nb_bt->dst_ip);
> +        if (!bfd_rp) {
> +            bfd_rp = bfd_alloc_entry(bfd_active_connections,
> +                                     nb_bt->logical_port, nb_bt->dst_ip,
> +                                     bfd_e->status);
>          }
>
> -        ret = strcmp(nb_bt->status, "down");
> -        ovs_mutex_unlock(&bfd_lock);
> -        break;
> +        if (!strcmp(bfd_e->status, "admin_down")) {
> +            bfd_set_status(bfd_rp, "down");
> +        }
> +
> +        return strcmp(bfd_rp->status, "down");
>      }
>
> -    return ret;
> +    return true;
>  }
>
>  static void
>  build_routing_policy_flow(struct lflow_table *lflows, struct ovn_datapath *od,
> -                          const struct hmap *lr_ports,
> -                          const struct nbrec_logical_router_policy *rule,
> -                          const struct hmap *bfd_connections,
> +                          const struct hmap *lr_ports, struct route_policy *rp,
>                            const struct ovsdb_idl_row *stage_hint,
>                            struct lflow_ref *lflow_ref)
>  {
> +    const struct nbrec_logical_router_policy *rule = rp->rule;
>      struct ds match = DS_EMPTY_INITIALIZER;
>      struct ds actions = DS_EMPTY_INITIALIZER;
>
>      if (!strcmp(rule->action, "reroute")) {
>          ovs_assert(rule->n_nexthops <= 1);
>
> -        char *nexthop =
> -            (rule->n_nexthops == 1 ? rule->nexthops[0] : rule->nexthop);
> +        if (!rp->n_valid_nexthops) {
> +            return;
> +        }
> +
> +        char *nexthop = rp->valid_nexthops[0];
>          struct ovn_port *out_port = get_outport_for_routing_policy_nexthop(
>               od, lr_ports, rule->priority, nexthop);
>          if (!out_port) {
> @@ -10024,10 +10106,6 @@ build_routing_policy_flow(struct lflow_table *lflows, struct ovn_datapath *od,
>              return;
>          }
>
> -        if (!check_bfd_state(rule, bfd_connections, out_port, nexthop)) {
> -            return;
> -        }
> -
>          uint32_t pkt_mark = smap_get_uint(&rule->options, "pkt_mark", 0);
>          if (pkt_mark) {
>              ds_put_format(&actions, "pkt.mark = %u; ", pkt_mark);
> @@ -10070,19 +10148,18 @@ static void
>  build_ecmp_routing_policy_flows(struct lflow_table *lflows,
>                                  struct ovn_datapath *od,
>                                  const struct hmap *lr_ports,
> -                                const struct nbrec_logical_router_policy *rule,
> -                                const struct hmap *bfd_connections,
> +                                struct route_policy *rp,
>                                  uint16_t ecmp_group_id,
>                                  struct lflow_ref *lflow_ref)
>  {
> -    ovs_assert(rule->n_nexthops > 1);
> -
>      bool nexthops_is_ipv4 = true;
> +    const struct nbrec_logical_router_policy *rule = rp->rule;
> +    ovs_assert(rule->n_nexthops > 1);
>
>      /* Check that all the nexthops belong to the same addr family before
>       * adding logical flows. */
> -    for (uint16_t i = 0; i < rule->n_nexthops; i++) {
> -        bool is_ipv4 = strchr(rule->nexthops[i], '.') ? true : false;
> +    for (uint16_t i = 0; i < rp->n_valid_nexthops; i++) {
> +        bool is_ipv4 = strchr(rp->valid_nexthops[i], '.') ? true : false;
>
>          if (i == 0) {
>              nexthops_is_ipv4 = is_ipv4;
> @@ -10093,7 +10170,7 @@ build_ecmp_routing_policy_flows(struct lflow_table *lflows,
>              VLOG_WARN_RL(&rl, "nexthop [%s] of the router policy with "
>                           "the match [%s] do not belong to the same address "
>                           "family as other next hops",
> -                         rule->nexthops[i], rule->match);
> +                         rp->valid_nexthops[i], rule->match);
>              return;
>          }
>      }
> @@ -10101,40 +10178,30 @@ build_ecmp_routing_policy_flows(struct lflow_table *lflows,
>      struct ds match = DS_EMPTY_INITIALIZER;
>      struct ds actions = DS_EMPTY_INITIALIZER;
>
> -    size_t *valid_nexthops = xcalloc(rule->n_nexthops, sizeof *valid_nexthops);
> -    size_t n_valid_nexthops = 0;
> -
> -    for (size_t i = 0; i < rule->n_nexthops; i++) {
> +    for (size_t i = 0; i < rp->n_valid_nexthops; i++) {
>          struct ovn_port *out_port = get_outport_for_routing_policy_nexthop(
> -             od, lr_ports, rule->priority, rule->nexthops[i]);
> +             od, lr_ports, rule->priority, rp->valid_nexthops[i]);
>          if (!out_port) {
>              goto cleanup;
>          }
>
>          const char *lrp_addr_s =
> -            find_lrp_member_ip(out_port, rule->nexthops[i]);
> +            find_lrp_member_ip(out_port, rp->valid_nexthops[i]);
>          if (!lrp_addr_s) {
>              static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 1);
>              VLOG_WARN_RL(&rl, "lrp_addr not found for routing policy "
>                              " priority %"PRId64" nexthop %s",
> -                            rule->priority, rule->nexthops[i]);
> +                            rule->priority, rp->valid_nexthops[i]);
>              goto cleanup;
>          }
>
> -        if (!check_bfd_state(rule, bfd_connections, out_port,
> -                             rule->nexthops[i])) {
> -            continue;
> -        }
> -
> -        valid_nexthops[n_valid_nexthops++] = i + 1;
> -
>          ds_clear(&actions);
>          uint32_t pkt_mark = smap_get_uint(&rule->options, "pkt_mark", 0);
>          if (pkt_mark) {
>              ds_put_format(&actions, "pkt.mark = %u; ", pkt_mark);
>          }
>
> -        bool is_ipv4 = strchr(rule->nexthops[i], '.') ? true : false;
> +        bool is_ipv4 = strchr(rp->valid_nexthops[i], '.') ? true : false;
>
>          ds_put_format(&actions, "%s = %s; "
>                        "%s = %s; "
> @@ -10143,7 +10210,7 @@ build_ecmp_routing_policy_flows(struct lflow_table *lflows,
>                        "flags.loopback = 1; "
>                        "next;",
>                        is_ipv4 ? REG_NEXT_HOP_IPV4 : REG_NEXT_HOP_IPV6,
> -                      rule->nexthops[i],
> +                      rp->valid_nexthops[i],
>                        is_ipv4 ? REG_SRC_IPV4 : REG_SRC_IPV6,
>                        lrp_addr_s,
>                        out_port->lrp_networks.ea_s,
> @@ -10159,37 +10226,30 @@ build_ecmp_routing_policy_flows(struct lflow_table *lflows,
>                                  lflow_ref);
>      }
>
> -    if (!n_valid_nexthops) {
> -        goto cleanup;
> -    }
> -
>      ds_clear(&actions);
> -    if (n_valid_nexthops > 1) {
> +    if (rp->n_valid_nexthops > 1) {
>          ds_put_format(&actions, "%s = %"PRIu16
>                        "; %s = select(", REG_ECMP_GROUP_ID, ecmp_group_id,
>                        REG_ECMP_MEMBER_ID);
>
> -        for (size_t i = 0; i < n_valid_nexthops; i++) {
> +        for (size_t i = 0; i < rp->n_valid_nexthops; i++) {
>              if (i > 0) {
>                  ds_put_cstr(&actions, ", ");
>              }
>
> -            ds_put_format(&actions, "%"PRIuSIZE, valid_nexthops[i]);
> +            ds_put_format(&actions, "%"PRIuSIZE, i + 1);
>          }
>          ds_put_cstr(&actions, ");");
>      } else {
>          ds_put_format(&actions, "%s = %"PRIu16
> -                      "; %s = %"PRIuSIZE"; next;", REG_ECMP_GROUP_ID,
> -                      ecmp_group_id, REG_ECMP_MEMBER_ID,
> -                      valid_nexthops[0]);
> +                      "; %s = 1; next;", REG_ECMP_GROUP_ID,
> +                      ecmp_group_id, REG_ECMP_MEMBER_ID);
>      }
>      ovn_lflow_add_with_hint(lflows, od, S_ROUTER_IN_POLICY,
>                              rule->priority, rule->match,
>                              ds_cstr(&actions), &rule->header_,
>                              lflow_ref);
> -
>  cleanup:
> -    free(valid_nexthops);
>      ds_destroy(&match);
>      ds_destroy(&actions);
>  }
> @@ -10214,7 +10274,7 @@ route_table_add(struct simap *route_tables, const char *route_table_name)
>      return rtb_id;
>  }
>
> -static uint32_t
> +uint32_t
>  get_route_table_id(struct simap *route_tables, const char *route_table_name)
>  {
>      if (!route_table_name || !route_table_name[0]) {
> @@ -10255,18 +10315,6 @@ build_route_table_lflow(struct ovn_datapath *od, struct lflow_table *lflows,
>      ds_destroy(&actions);
>  }
>
> -struct parsed_route {
> -    struct ovs_list list_node;
> -    struct in6_addr prefix;
> -    unsigned int plen;
> -    bool is_src_route;
> -    uint32_t route_table_id;
> -    uint32_t hash;
> -    const struct nbrec_logical_router_static_route *route;
> -    bool ecmp_symmetric_reply;
> -    bool is_discard_route;
> -};
> -
>  static uint32_t
>  route_hash(struct parsed_route *route)
>  {
> @@ -10281,11 +10329,53 @@ find_static_route_outport(struct ovn_datapath *od, const struct hmap *lr_ports,
>
>  /* Parse and validate the route. Return the parsed route if successful.
>   * Otherwise return NULL. */
> +
>  static struct parsed_route *
> +parsed_route_lookup(struct hmap *routes, size_t hash,
> +                    struct parsed_route *new_pr)
> +{
> +    struct parsed_route *pr;
> +    HMAP_FOR_EACH_WITH_HASH (pr, key_node, hash, routes) {
> +        if (pr->plen != new_pr->plen) {
> +            continue;
> +        }
> +
> +        if (memcmp(&pr->prefix, &new_pr->prefix, sizeof(struct in6_addr))) {
> +            continue;
> +        }
> +
> +        if (pr->is_src_route != new_pr->is_src_route) {
> +            continue;
> +        }
> +
> +        if (pr->route_table_id != new_pr->route_table_id) {
> +            continue;
> +        }
> +
> +        if (pr->route != new_pr->route) {
> +            continue;
> +        }
> +
> +        if (pr->ecmp_symmetric_reply != new_pr->ecmp_symmetric_reply) {
> +            continue;
> +        }
> +
> +        if (pr->is_discard_route != new_pr->is_discard_route) {
> +            continue;
> +        }
> +
> +        return pr;
> +    }
> +
> +    return NULL;
> +}
> +
> +static void
>  parsed_routes_add(struct ovn_datapath *od, const struct hmap *lr_ports,
> -                  struct ovs_list *routes, struct simap *route_tables,
>                    const struct nbrec_logical_router_static_route *route,
> -                  const struct hmap *bfd_connections)
> +                  struct hmap *bfd_connections,
> +                  struct hmap *routes, struct simap *route_tables,
> +                  struct hmap *bfd_active_connections)
>  {
>      /* Verify that the next hop is an IP address with an all-ones mask. */
>      struct in6_addr nexthop;
> @@ -10298,7 +10388,7 @@ parsed_routes_add(struct ovn_datapath *od, const struct hmap *lr_ports,
>              VLOG_WARN_RL(&rl, "bad 'nexthop' %s in static route "
>                           UUID_FMT, route->nexthop,
>                           UUID_ARGS(&route->header_.uuid));
> -            return NULL;
> +            return;
>          }
>          if ((IN6_IS_ADDR_V4MAPPED(&nexthop) && plen != 32) ||
>              (!IN6_IS_ADDR_V4MAPPED(&nexthop) && plen != 128)) {
> @@ -10306,7 +10396,7 @@ parsed_routes_add(struct ovn_datapath *od, const struct hmap *lr_ports,
>              VLOG_WARN_RL(&rl, "bad next hop mask %s in static route "
>                           UUID_FMT, route->nexthop,
>                           UUID_ARGS(&route->header_.uuid));
> -            return NULL;
> +            return;
>          }
>      }
>
> @@ -10317,7 +10407,7 @@ parsed_routes_add(struct ovn_datapath *od, const struct hmap *lr_ports,
>          VLOG_WARN_RL(&rl, "bad 'ip_prefix' %s in static route "
>                       UUID_FMT, route->ip_prefix,
>                       UUID_ARGS(&route->header_.uuid));
> -        return NULL;
> +        return;
>      }
>
>      /* Verify that ip_prefix and nexthop have same address familiy. */
> @@ -10328,7 +10418,7 @@ parsed_routes_add(struct ovn_datapath *od, const struct hmap *lr_ports,
>                           " %s and 'nexthop' %s in static route "UUID_FMT,
>                           route->ip_prefix, route->nexthop,
>                           UUID_ARGS(&route->header_.uuid));
> -            return NULL;
> +            return;
>          }
>      }
>
> @@ -10337,52 +10427,88 @@ parsed_routes_add(struct ovn_datapath *od, const struct hmap *lr_ports,
>          !find_static_route_outport(od, lr_ports, route,
>                                     IN6_IS_ADDR_V4MAPPED(&prefix),
>                                     NULL, NULL)) {
> -        return NULL;
> +        return;
>      }
>
>      const struct nbrec_bfd *nb_bt = route->bfd;
>      if (nb_bt && !strcmp(nb_bt->dst_ip, route->nexthop)) {
> -        struct bfd_entry *bfd_e;
> +        struct bfd_entry *bfd_e = bfd_port_lookup(bfd_connections,
> +                                                  nb_bt->logical_port,
> +                                                  nb_bt->dst_ip);
> +        if (!bfd_e) {
> +            return;
> +        }
>
> -        bfd_e = bfd_port_lookup(bfd_connections, nb_bt->logical_port,
> -                                nb_bt->dst_ip);
> -        ovs_mutex_lock(&bfd_lock);
> -        if (bfd_e) {
> -            bfd_e->ref = true;
> +        /* This static route is linked to an active bfd session. */
> +        struct bfd_entry *bfd_sr = bfd_port_lookup(bfd_active_connections,
> +                                                   nb_bt->logical_port,
> +                                                   nb_bt->dst_ip);
> +        if (!bfd_sr) {
> +            bfd_sr = bfd_alloc_entry(bfd_active_connections,
> +                                     nb_bt->logical_port, nb_bt->dst_ip,
> +                                     bfd_e->status);
>          }
>
> -        if (!strcmp(nb_bt->status, "admin_down")) {
> -            nbrec_bfd_set_status(nb_bt, "down");
> +        if (!strcmp(bfd_e->status, "admin_down")) {
> +            bfd_set_status(bfd_sr, "down");
>          }
>
> -        if (!strcmp(nb_bt->status, "down")) {
> -            ovs_mutex_unlock(&bfd_lock);
> -            return NULL;
> +
> +        if (!strcmp(bfd_sr->status, "down")) {
> +            return;
>          }
> -        ovs_mutex_unlock(&bfd_lock);
>      }
>
> -    struct parsed_route *pr = xzalloc(sizeof *pr);
> -    pr->prefix = prefix;
> -    pr->plen = plen;
> -    pr->route_table_id = get_route_table_id(route_tables, route->route_table);
> -    pr->is_src_route = (route->policy && !strcmp(route->policy,
> -                                                 "src-ip"));
> -    pr->hash = route_hash(pr);
> -    pr->route = route;
> -    pr->ecmp_symmetric_reply = smap_get_bool(&route->options,
> -                                             "ecmp_symmetric_reply", false);
> -    pr->is_discard_route = is_discard_route;
> -    ovs_list_insert(routes, &pr->list_node);
> -    return pr;
> +    struct parsed_route *new_pr = xzalloc(sizeof *new_pr);
> +    new_pr->prefix = prefix;
> +    new_pr->plen = plen;
> +    new_pr->route_table_id = get_route_table_id(route_tables,
> +                                                route->route_table);
> +    new_pr->is_src_route = (route->policy &&
> +                            !strcmp(route->policy, "src-ip"));
> +    new_pr->hash = route_hash(new_pr);
> +    new_pr->route = route;
> +    new_pr->nbr = od->nbr;
> +    new_pr->ecmp_symmetric_reply = smap_get_bool(&route->options,
> +                                                 "ecmp_symmetric_reply",
> +                                                 false);
> +    new_pr->is_discard_route = is_discard_route;
> +
> +    size_t hash = uuid_hash(&od->key);
> +    struct parsed_route *pr = parsed_route_lookup(routes, hash, new_pr);
> +    if (!pr) {
> +        hmap_insert(routes, &new_pr->key_node, hash);
> +    } else {
> +        pr->stale = false;
> +        free(new_pr);
> +    }
>  }
>
> -static void
> -parsed_routes_destroy(struct ovs_list *routes)
> +void
> +build_parsed_routes(struct ovn_datapath *od, const struct hmap *lr_ports,
> +                    struct hmap *bfd_connections, struct hmap *routes,
> +                    struct simap *route_tables,
> +                    struct hmap *bfd_active_connections)
>  {
>      struct parsed_route *pr;
> -    LIST_FOR_EACH_SAFE (pr, list_node, routes) {
> -        ovs_list_remove(&pr->list_node);
> +    HMAP_FOR_EACH (pr, key_node, routes) {
> +        if (pr->nbr == od->nbr) {
> +            pr->stale = true;
> +        }
> +    }
> +
> +    for (int i = 0; i < od->nbr->n_static_routes; i++) {
> +        parsed_routes_add(od, lr_ports, od->nbr->static_routes[i],
> +                          bfd_connections, routes, route_tables,
> +                          bfd_active_connections);
> +    }
> +
> +    HMAP_FOR_EACH_SAFE (pr, key_node, routes) {
> +        if (!pr->stale) {
> +            continue;
> +        }
> +
> +        hmap_remove(routes, &pr->key_node);
>          free(pr);
>      }
>  }
> @@ -12684,8 +12810,8 @@ build_ip_routing_flows_for_lrp(
>  static void
>  build_static_route_flows_for_lrouter(
>          struct ovn_datapath *od, struct lflow_table *lflows,
> -        const struct hmap *lr_ports, const struct hmap *bfd_connections,
> -        struct lflow_ref *lflow_ref)
> +        const struct hmap *lr_ports, struct hmap *parsed_routes,
> +        struct simap *route_tables, struct lflow_ref *lflow_ref)
>  {
>      ovs_assert(od->nbr);
>      ovn_lflow_add_default_drop(lflows, od, S_ROUTER_IN_IP_ROUTING_ECMP,
> @@ -12698,22 +12824,16 @@ build_static_route_flows_for_lrouter(
>
>      struct hmap ecmp_groups = HMAP_INITIALIZER(&ecmp_groups);
>      struct hmap unique_routes = HMAP_INITIALIZER(&unique_routes);
> -    struct ovs_list parsed_routes = OVS_LIST_INITIALIZER(&parsed_routes);
> -    struct simap route_tables = SIMAP_INITIALIZER(&route_tables);
>      struct ecmp_groups_node *group;
>
>      for (int i = 0; i < od->nbr->n_ports; i++) {
>          build_route_table_lflow(od, lflows, od->nbr->ports[i],
> -                                &route_tables, lflow_ref);
> +                                route_tables, lflow_ref);
>      }
>
> -    for (int i = 0; i < od->nbr->n_static_routes; i++) {
> -        struct parsed_route *route =
> -            parsed_routes_add(od, lr_ports, &parsed_routes, &route_tables,
> -                              od->nbr->static_routes[i], bfd_connections);
> -        if (!route) {
> -            continue;
> -        }
> +    struct parsed_route *route;
> +    HMAP_FOR_EACH_WITH_HASH (route, key_node, uuid_hash(&od->key),
> +                             parsed_routes) {
>          group = ecmp_groups_find(&ecmp_groups, route);
>          if (group) {
>              ecmp_groups_add_route(group, route);
> @@ -12741,8 +12861,6 @@ build_static_route_flows_for_lrouter(
>      }
>      ecmp_groups_destroy(&ecmp_groups);
>      unique_routes_destroy(&unique_routes);
> -    parsed_routes_destroy(&parsed_routes);
> -    simap_destroy(&route_tables);
>  }
>
>  /* IP Multicast lookup. Here we set the output port, adjust TTL and
> @@ -12849,6 +12967,115 @@ build_mcast_lookup_flows_for_lrouter(
>      }
>  }
>
> +static struct route_policy *
> +route_policies_lookup(struct hmap *route_policies, size_t hash,
> +                      struct route_policy *new_rp)
> +{
> +    struct route_policy *rp;
> +    HMAP_FOR_EACH_WITH_HASH (rp, key_node, hash, route_policies) {
> +        if (rp->rule != new_rp->rule) {
> +            continue;
> +        }
> +
> +        if (rp->n_valid_nexthops != new_rp->n_valid_nexthops) {
> +            continue;
> +        }
> +
> +        size_t i;
> +        for (i = 0; i < new_rp->n_valid_nexthops; i++) {
> +            size_t j;
> +
> +            for (j = 0; j < rp->n_valid_nexthops; j++) {
> +                if (!strcmp(new_rp->valid_nexthops[i],
> +                            rp->valid_nexthops[j])) {
> +                    break;
> +                }
> +            }
> +
> +            if (j == rp->n_valid_nexthops) {
> +                break;
> +            }
> +        }
> +
> +        if (i == new_rp->n_valid_nexthops) {
> +            return rp;
> +        }
> +    }
> +
> +    return NULL;
> +}
> +
> +void
> +build_route_policies(struct ovn_datapath *od, struct hmap *lr_ports,
> +                     struct hmap *bfd_connections,
> +                     struct hmap *route_policies,
> +                     struct hmap *bfd_active_connections)
> +{
> +    struct route_policy *rp;
> +
> +    HMAP_FOR_EACH (rp, key_node, route_policies) {
> +        if (rp->nbr == od->nbr) {
> +            rp->stale = true;
> +        }
> +    }
> +
> +    for (int i = 0; i < od->nbr->n_policies; i++) {
> +        const struct nbrec_logical_router_policy *rule = od->nbr->policies[i];
> +        size_t n_valid_nexthops = 0;
> +        char **valid_nexthops = NULL;
> +
> +        if (!strcmp(rule->action, "reroute")) {
> +            size_t n_nexthops = rule->n_nexthops ? rule->n_nexthops : 1;
> +
> +            valid_nexthops = xcalloc(n_nexthops, sizeof *valid_nexthops);
> +            for (size_t j = 0; j < n_nexthops; j++) {
> +                char *nexthop = rule->n_nexthops
> +                    ? rule->nexthops[j] : rule->nexthop;
> +                struct ovn_port *out_port =
> +                    get_outport_for_routing_policy_nexthop(
> +                            od, lr_ports, rule->priority, nexthop);
> +                if (!out_port || !check_bfd_state(rule, out_port, nexthop,
> +                                                  bfd_connections,
> +                                                  bfd_active_connections)) {
> +                    continue;
> +                }
> +                valid_nexthops[n_valid_nexthops++] = nexthop;
> +            }
> +
> +            if (!n_valid_nexthops) {
> +                free(valid_nexthops);
> +                continue;
> +            }
> +        }
> +
> +        struct route_policy *new_rp = xzalloc(sizeof *new_rp);
> +        new_rp->rule = rule;
> +        new_rp->n_valid_nexthops = n_valid_nexthops;
> +        new_rp->valid_nexthops = valid_nexthops;
> +        new_rp->nbr = od->nbr;
> +
> +        size_t hash = uuid_hash(&od->key);
> +        rp = route_policies_lookup(route_policies, hash, new_rp);
> +        if (!rp) {
> +            hmap_insert(route_policies, &new_rp->key_node, hash);
> +        } else {
> +            rp->stale = false;
> +            free(valid_nexthops);
> +            free(new_rp);
> +        }
> +    }
> +
> +    HMAP_FOR_EACH_SAFE (rp, key_node, route_policies) {
> +        if (!rp->stale) {
> +            continue;
> +        }
> +
> +        hmap_remove(route_policies, &rp->key_node);
> +        free(rp->valid_nexthops);
> +        free(rp);
> +    }
> +}
> +
>  /* Logical router ingress table POLICY: Policy.
>   *
>   * A packet that arrives at this table is an IP packet that should be
> @@ -12862,7 +13089,7 @@ static void
>  build_ingress_policy_flows_for_lrouter(
>          struct ovn_datapath *od, struct lflow_table *lflows,
>          const struct hmap *lr_ports,
> -        const struct hmap *bfd_connections,
> +        struct hmap *route_policies,
>          struct lflow_ref *lflow_ref)
>  {
>      ovs_assert(od->nbr);
> @@ -12879,21 +13106,20 @@ build_ingress_policy_flows_for_lrouter(
>
>      /* Convert routing policies to flows. */
>      uint16_t ecmp_group_id = 1;
> -    for (int i = 0; i < od->nbr->n_policies; i++) {
> -        const struct nbrec_logical_router_policy *rule
> -            = od->nbr->policies[i];
> +    struct route_policy *rp;
> +    HMAP_FOR_EACH_WITH_HASH (rp, key_node, uuid_hash(&od->key),
> +                             route_policies) {
> +        const struct nbrec_logical_router_policy *rule = rp->rule;
>          bool is_ecmp_reroute =
>              (!strcmp(rule->action, "reroute") && rule->n_nexthops > 1);
>
>          if (is_ecmp_reroute) {
> -            build_ecmp_routing_policy_flows(lflows, od, lr_ports, rule,
> -                                            bfd_connections, ecmp_group_id,
> -                                            lflow_ref);
> +            build_ecmp_routing_policy_flows(lflows, od, lr_ports, rp,
> +                                            ecmp_group_id, lflow_ref);
>              ecmp_group_id++;
>          } else {
> -            build_routing_policy_flow(lflows, od, lr_ports, rule,
> -                                      bfd_connections, &rule->header_,
> -                                      lflow_ref);
> +            build_routing_policy_flow(lflows, od, lr_ports, rp,
> +                                      &rule->header_, lflow_ref);
>          }
>      }
>  }
> @@ -15818,6 +16044,9 @@ struct lswitch_flow_build_info {
>      struct ds actions;
>      size_t thread_lflow_counter;
>      const char *svc_monitor_mac;
> +    struct hmap *parsed_routes;
> +    struct hmap *route_policies;
> +    struct simap *route_tables;
>  };
>
>  /* Helper function to combine all lflow generation which is iterated by
> @@ -15863,12 +16092,12 @@ build_lswitch_and_lrouter_iterate_by_lr(struct ovn_datapath *od,
>      build_ND_RA_flows_for_lrouter(od, lsi->lflows, NULL);
>      build_ip_routing_pre_flows_for_lrouter(od, lsi->lflows, NULL);
>      build_static_route_flows_for_lrouter(od, lsi->lflows, lsi->lr_ports,
> -                                         lsi->bfd_connections,
> +                                         lsi->parsed_routes, lsi->route_tables,
>                                           NULL);
>      build_mcast_lookup_flows_for_lrouter(od, lsi->lflows, &lsi->match,
>                                           &lsi->actions, NULL);
>      build_ingress_policy_flows_for_lrouter(od, lsi->lflows, lsi->lr_ports,
> -                                           lsi->bfd_connections, NULL);
> +                                           lsi->route_policies, NULL);
>      build_arp_resolve_flows_for_lrouter(od, lsi->lflows, NULL);
>      build_check_pkt_len_flows_for_lrouter(od, lsi->lflows, lsi->lr_ports,
>                                            &lsi->match, &lsi->actions,
> @@ -16182,7 +16411,10 @@ build_lswitch_and_lrouter_flows(
>      const struct hmap *svc_monitor_map,
>      const struct hmap *bfd_connections,
>      const struct chassis_features *features,
> -    const char *svc_monitor_mac)
> +    const char *svc_monitor_mac,
> +    struct hmap *parsed_routes,
> +    struct hmap *route_policies,
> +    struct simap *route_tables)
>  {
>
>      char *svc_check_match = xasprintf("eth.dst == %s", svc_monitor_mac);
> @@ -16216,6 +16448,9 @@ build_lswitch_and_lrouter_flows(
>              lsiv[index].svc_check_match = svc_check_match;
>              lsiv[index].thread_lflow_counter = 0;
>              lsiv[index].svc_monitor_mac = svc_monitor_mac;
> +            lsiv[index].parsed_routes = parsed_routes;
> +            lsiv[index].route_tables = route_tables;
> +            lsiv[index].route_policies = route_policies;
>              ds_init(&lsiv[index].match);
>              ds_init(&lsiv[index].actions);
>
> @@ -16256,6 +16491,9 @@ build_lswitch_and_lrouter_flows(
>              .features = features,
>              .svc_check_match = svc_check_match,
>              .svc_monitor_mac = svc_monitor_mac,
> +            .parsed_routes = parsed_routes,
> +            .route_tables = route_tables,
> +            .route_policies = route_policies,
>              .match = DS_EMPTY_INITIALIZER,
>              .actions = DS_EMPTY_INITIALIZER,
>          };
> @@ -16417,7 +16655,10 @@ void build_lflows(struct ovsdb_idl_txn *ovnsb_txn,
>                                      input_data->svc_monitor_map,
>                                      input_data->bfd_connections,
>                                      input_data->features,
> -                                    input_data->svc_monitor_mac);
> +                                    input_data->svc_monitor_mac,
> +                                    input_data->parsed_routes,
> +                                    input_data->route_policies,
> +                                    input_data->route_tables);
>
>      if (parallelization_state == STATE_INIT_HASH_SIZES) {
>          parallelization_state = STATE_USE_PARALLELIZATION;
> @@ -17490,6 +17731,27 @@ northd_init(struct northd_data *data)
>      init_northd_tracked_data(data);
>  }
>
> +void
> +route_policies_init(struct route_policies_data *data)
> +{
> +    hmap_init(&data->route_policies);
> +    hmap_init(&data->bfd_active_connections);
> +}
> +
> +void
> +static_routes_init(struct static_routes_data *data)
> +{
> +    hmap_init(&data->parsed_routes);
> +    simap_init(&data->route_tables);
> +    hmap_init(&data->bfd_active_connections);
> +}
> +
> +void
> +bfd_init(struct bfd_data *data)
> +{
> +    hmap_init(&data->bfd_connections);
> +}
> +
>  void
>  northd_destroy(struct northd_data *data)
>  {
> @@ -17529,6 +17791,48 @@ northd_destroy(struct northd_data *data)
>      destroy_northd_tracked_data(data);
>  }
>
> +static void
> +__bfd_destroy(struct hmap *bfd_connections)
> +{
> +    struct bfd_entry *bfd_e;
> +
> +    HMAP_FOR_EACH_POP (bfd_e, hmap_node, bfd_connections) {
> +        bfd_erase_entry(bfd_e);
> +    }
> +    hmap_destroy(bfd_connections);
> +}
> +
> +void
> +bfd_destroy(struct bfd_data *data)
> +{
> +    __bfd_destroy(&data->bfd_connections);
> +}
> +
> +void
> +route_policies_destroy(struct route_policies_data *data)
> +{
> +    struct route_policy *rp;
> +    HMAP_FOR_EACH_POP (rp, key_node, &data->route_policies) {
> +        free(rp->valid_nexthops);
> +        free(rp);
> +    };
> +    hmap_destroy(&data->route_policies);
> +    __bfd_destroy(&data->bfd_active_connections);
> +}
> +
> +void
> +static_routes_destroy(struct static_routes_data *data)
> +{
> +    struct parsed_route *r;
> +    HMAP_FOR_EACH_POP (r, key_node, &data->parsed_routes) {
> +        free(r);
> +    }
> +    hmap_destroy(&data->parsed_routes);
> +
> +    simap_destroy(&data->route_tables);
> +    __bfd_destroy(&data->bfd_active_connections);
> +}
> +
>  void
>  ovnnb_db_run(struct northd_input *input_data,
>               struct northd_data *data,
> diff --git a/northd/northd.h b/northd/northd.h
> index d4a8d75ab..37f06ce5d 100644
> --- a/northd/northd.h
> +++ b/northd/northd.h
> @@ -23,6 +23,7 @@
>  #include "northd/en-port-group.h"
>  #include "northd/ipam.h"
>  #include "openvswitch/hmap.h"
> +#include "simap.h"
>  #include "ovs-thread.h"
>
>  struct northd_input {
> @@ -160,14 +161,34 @@ struct northd_data {
>      struct northd_tracked_data trk_data;
>  };
>
> +struct route_policy {
> +    struct hmap_node key_node;
> +    const struct nbrec_logical_router_policy *rule;
> +    size_t n_valid_nexthops;
> +    char **valid_nexthops;
> +    const struct nbrec_logical_router *nbr;
> +    bool stale;
> +};
> +
> +struct static_routes_data {
> +    struct hmap parsed_routes;
> +    struct simap route_tables;
> +    struct hmap bfd_active_connections;
> +};
> +
> +struct route_policies_data {
> +    struct hmap route_policies;
> +    struct hmap bfd_active_connections;
> +};
> +
> +struct bfd_data {
> +    struct hmap bfd_connections;
> +};
> +
>  struct lr_nat_table;
>
>  struct lflow_input {
> -    /* Northbound table references */
> -    const struct nbrec_bfd_table *nbrec_bfd_table;
> -
>      /* Southbound table references */
> -    const struct sbrec_bfd_table *sbrec_bfd_table;
>      const struct sbrec_logical_flow_table *sbrec_logical_flow_table;
>      const struct sbrec_multicast_group_table *sbrec_multicast_group_table;
>      const struct sbrec_igmp_group_table *sbrec_igmp_group_table;
> @@ -190,6 +211,9 @@ struct lflow_input {
>      const struct hmap *svc_monitor_map;
>      bool ovn_internal_version_changed;
>      const char *svc_monitor_mac;
> +    struct hmap *parsed_routes;
> +    struct hmap *route_policies;
> +    struct simap *route_tables;
>  };
>
>  extern int parallelization_state;
> @@ -653,6 +677,20 @@ struct ovn_port {
>      struct lflow_ref *stateful_lflow_ref;
>  };
>
> +struct parsed_route {
> +    struct hmap_node key_node;
> +    struct in6_addr prefix;
> +    unsigned int plen;
> +    bool is_src_route;
> +    uint32_t route_table_id;
> +    uint32_t hash;
> +    const struct nbrec_logical_router_static_route *route;
> +    bool ecmp_symmetric_reply;
> +    bool is_discard_route;
> +    const struct nbrec_logical_router *nbr;
> +    bool stale;
> +};
> +
>  void ovnnb_db_run(struct northd_input *input_data,
>                    struct northd_data *data,
>                    struct ovsdb_idl_txn *ovnnb_txn,
> @@ -674,6 +712,18 @@ void northd_init(struct northd_data *data);
>  void northd_indices_create(struct northd_data *data,
>                             struct ovsdb_idl *ovnsb_idl);
>
> +void route_policies_init(struct route_policies_data *);
> +void route_policies_destroy(struct route_policies_data *);
> +void build_parsed_routes(struct ovn_datapath *, const struct hmap *,
> +                         struct hmap *, struct hmap *, struct simap *,
> +                         struct hmap *);
> +uint32_t get_route_table_id(struct simap *, const char *);
> +void static_routes_init(struct static_routes_data *);
> +void static_routes_destroy(struct static_routes_data *);
> +
> +void bfd_init(struct bfd_data *);
> +void bfd_destroy(struct bfd_data *);
> +
>  struct lflow_table;
>  struct lr_stateful_tracked_data;
>  struct ls_stateful_tracked_data;
> @@ -711,13 +761,13 @@ bool northd_handle_lb_data_changes(struct tracked_lb_data *,
>                                     struct hmap *lbgrp_datapaths_map,
>                                     struct northd_tracked_data *);
>
> -void build_bfd_table(struct ovsdb_idl_txn *ovnsb_txn,
> -                     const struct nbrec_bfd_table *,
> -                     const struct sbrec_bfd_table *,
> -                     const struct hmap *lr_ports,
> -                     struct hmap *bfd_connections);
> -void bfd_cleanup_connections(const struct nbrec_bfd_table *,
> -                             struct hmap *bfd_map);
> +void build_route_policies(struct ovn_datapath *, struct hmap *, struct hmap *,
> +                          struct hmap *, struct hmap *);
> +void bfd_table_sync(struct ovsdb_idl_txn *, const struct nbrec_bfd_table *,
> +                    const struct hmap *, struct hmap *, struct hmap *,
> +                    struct hmap *);
> +void build_bfd_map(const struct nbrec_bfd_table *,
> +                   const struct sbrec_bfd_table *, struct hmap *);
>  void run_update_worker_pool(int n_threads);
>
>  const struct ovn_datapath *northd_get_datapath_for_port(
> diff --git a/tests/ovn-northd.at b/tests/ovn-northd.at
> index 199197f09..710500dce 100644
> --- a/tests/ovn-northd.at
> +++ b/tests/ovn-northd.at
> @@ -12,6 +12,7 @@ m4_define([_DUMP_DB_TABLES], [
>      ovn-sbctl list meter >> $1
>      ovn-sbctl list meter_band >> $1
>      ovn-sbctl list port_group >> $1
> +    ovn-sbctl list bfd >> $1
>      ovn-sbctl dump-flows > lflows_$1
>  ])
>
> @@ -3861,6 +3862,7 @@ for i in $(seq 1 9); do
>      check ovn-nbctl --wait=sb lsp-set-addresses sw$i-r0 00:00:00:00:00:0$i
>  done
>
> +check as northd ovn-appctl -t ovn-northd inc-engine/clear-stats
>  uuid=$(ovn-nbctl create bfd logical_port=r0-sw1 dst_ip=192.168.1.2 status=down min_tx=250 min_rx=250 detect_mult=10)
>  ovn-nbctl create bfd logical_port=r0-sw2 dst_ip=192.168.2.2 status=down min_tx=500 min_rx=500 detect_mult=20
>  ovn-nbctl create bfd logical_port=r0-sw3 dst_ip=192.168.3.2 status=down
> @@ -3873,6 +3875,13 @@ wait_row_count bfd 1 logical_port=r0-sw2 detect_mult=20 dst_ip=192.168.2.2 \
>  wait_row_count bfd 1 logical_port=r0-sw3 detect_mult=5 dst_ip=192.168.3.2 \
>                       min_rx=1000 min_tx=1000 status=admin_down
>
> +check_engine_stats northd norecompute nocompute
> +check_engine_stats bfd recompute nocompute
> +check_engine_stats lflow recompute nocompute
> +check_engine_stats northd_output norecompute compute
> +CHECK_NO_CHANGE_AFTER_RECOMPUTE
> +check as northd ovn-appctl -t ovn-northd inc-engine/clear-stats
> +
>  uuid=$(fetch_column nb:bfd _uuid logical_port=r0-sw1)
>  check ovn-nbctl set bfd $uuid min_tx=1000 min_rx=1000 detect_mult=100
>
> @@ -3881,10 +3890,25 @@ check ovn-nbctl clear bfd $uuid_2 min_rx
>  wait_row_count bfd 1 logical_port=r0-sw2 min_rx=1000
>  wait_row_count bfd 1 logical_port=r0-sw1 min_rx=1000 min_tx=1000 detect_mult=100
>
> +check_engine_stats northd norecompute nocompute
> +check_engine_stats bfd recompute nocompute
> +check_engine_stats lflow recompute nocompute
> +check_engine_stats northd_output norecompute compute
> +CHECK_NO_CHANGE_AFTER_RECOMPUTE
> +check as northd ovn-appctl -t ovn-northd inc-engine/clear-stats
> +
>  check ovn-nbctl --bfd=$uuid lr-route-add r0 100.0.0.0/8 192.168.1.2
>  wait_column down bfd status logical_port=r0-sw1
>  AT_CHECK([ovn-nbctl lr-route-list r0 | grep 192.168.1.2 | grep -q bfd],[0])
>
> +check_engine_stats northd recompute nocompute
> +check_engine_stats bfd recompute nocompute
> +check_engine_stats static_routes recompute nocompute
> +check_engine_stats lflow recompute nocompute
> +check_engine_stats northd_output norecompute compute
> +CHECK_NO_CHANGE_AFTER_RECOMPUTE
> +check as northd ovn-appctl -t ovn-northd inc-engine/clear-stats
> +
>  check ovn-nbctl --bfd lr-route-add r0 200.0.0.0/8 192.168.2.2
>  wait_column down bfd status logical_port=r0-sw2
>  AT_CHECK([ovn-nbctl lr-route-list r0 | grep 192.168.2.2 | grep -q bfd],[0])
> @@ -3893,10 +3917,26 @@ check ovn-nbctl --bfd lr-route-add r0 240.0.0.0/8 192.168.5.2 r0-sw5
>  wait_column down bfd status logical_port=r0-sw5
>  AT_CHECK([ovn-nbctl lr-route-list r0 | grep 192.168.5.2 | grep -q bfd],[0])
>
> +check_engine_stats northd recompute nocompute
> +check_engine_stats bfd recompute nocompute
> +check_engine_stats static_routes recompute nocompute
> +check_engine_stats lflow recompute nocompute
> +check_engine_stats northd_output norecompute compute
> +CHECK_NO_CHANGE_AFTER_RECOMPUTE
> +check as northd ovn-appctl -t ovn-northd inc-engine/clear-stats
> +
>  check ovn-nbctl --bfd --policy=src-ip lr-route-add r0 192.168.6.1/32 192.168.10.10 r0-sw6
>  wait_column down bfd status logical_port=r0-sw6
>  AT_CHECK([ovn-nbctl lr-route-list r0 | grep 192.168.6.1 | grep -q bfd],[0])
>
> +check_engine_stats northd recompute nocompute
> +check_engine_stats bfd recompute nocompute
> +check_engine_stats route_policies recompute nocompute
> +check_engine_stats lflow recompute nocompute
> +check_engine_stats northd_output norecompute compute
> +CHECK_NO_CHANGE_AFTER_RECOMPUTE
> +check as northd ovn-appctl -t ovn-northd inc-engine/clear-stats
> +
>  check ovn-nbctl --bfd --policy=src-ip lr-route-add r0 192.168.7.1/32 192.168.10.10 r0-sw7
>  wait_column down bfd status logical_port=r0-sw7
>  AT_CHECK([ovn-nbctl lr-route-list r0 | grep 192.168.7.1 | grep -q bfd],[0])
> @@ -3924,6 +3964,14 @@ wait_column down bfd status logical_port=r0-sw8
>  bfd_route_policy_uuid=$(fetch_column nb:bfd _uuid logical_port=r0-sw8)
>  AT_CHECK([ovn-nbctl list logical_router_policy | grep -q $bfd_route_policy_uuid])
>
> +check_engine_stats northd recompute nocompute
> +check_engine_stats bfd recompute nocompute
> +check_engine_stats static_routes recompute nocompute
> +check_engine_stats lflow recompute nocompute
> +check_engine_stats northd_output norecompute compute
> +CHECK_NO_CHANGE_AFTER_RECOMPUTE
> +check as northd ovn-appctl -t ovn-northd inc-engine/clear-stats
> +
>  check ovn-nbctl lr-policy-del r0
>  check ovn-nbctl --bfd lr-policy-add r0 100 "ip4.src == 2.3.4.0/24" reroute 192.168.9.2,192.168.9.3,192.168.9.4
>
> @@ -3931,6 +3979,14 @@ wait_column down bfd status dst_ip=192.168.9.2
>  wait_column down bfd status dst_ip=192.168.9.3
>  wait_column down bfd status dst_ip=192.168.9.4
>
> +check_engine_stats northd recompute nocompute
> +check_engine_stats bfd recompute nocompute
> +check_engine_stats route_policies recompute nocompute
> +check_engine_stats lflow recompute nocompute
> +check_engine_stats northd_output norecompute compute
> +CHECK_NO_CHANGE_AFTER_RECOMPUTE
> +check as northd ovn-appctl -t ovn-northd inc-engine/clear-stats
> +
>  bfd_route_policy_uuid=$(fetch_column nb:bfd _uuid logical_port=r0-sw9)
>  AT_CHECK([ovn-nbctl list logical_router_policy | sed s/,//g | grep -q "$bfd_route_policy_uuid"])
>
> --
> 2.45.2
>

[...]
> > +    engine_add_input(&en_static_routes, &en_bfd, NULL);
> > +    engine_add_input(&en_static_routes, &en_northd,
> > +                     static_routes_northd_change_handler);
> > +
> > +    engine_add_input(&en_bfd_sync, &en_bfd, NULL);
> > +    engine_add_input(&en_bfd_sync, &en_nb_bfd, NULL);
> > +    engine_add_input(&en_bfd_sync, &en_static_routes, NULL);
> > +    engine_add_input(&en_bfd_sync, &en_route_policies, NULL);
> > +    engine_add_input(&en_bfd_sync, &en_northd, bfd_sync_change_handler);
> 
> nit: The change handler naming convention is
> <node>_<input>_change_handler, so it should be
> bfd_sync_northd_change_handler.

ack, I will fix it in v11.

> 
> > +
> >      engine_add_input(&en_sync_meters, &en_nb_acl, NULL);
> >      engine_add_input(&en_sync_meters, &en_nb_meter, NULL);
> >      engine_add_input(&en_sync_meters, &en_sb_meter, NULL);
> >
> > -    engine_add_input(&en_lflow, &en_nb_bfd, NULL);
> >      engine_add_input(&en_lflow, &en_nb_acl, NULL);
> >      engine_add_input(&en_lflow, &en_sync_meters, NULL);
> > -    engine_add_input(&en_lflow, &en_sb_bfd, NULL);
> >      engine_add_input(&en_lflow, &en_sb_logical_flow, NULL);
> >      engine_add_input(&en_lflow, &en_sb_multicast_group, NULL);
> >      engine_add_input(&en_lflow, &en_sb_igmp_group, NULL);
> >      engine_add_input(&en_lflow, &en_sb_logical_dp_group, NULL);
> > +    engine_add_input(&en_lflow, &en_bfd, NULL);
> > +    engine_add_input(&en_lflow, &en_bfd_sync, NULL);
> 
> I guess the reason why this input is required here is because there is
> a hidden dependency: the bfd_sync node updates lr_ports op->has_bfd
> field, and the en_lflow node depends on this field. If this is the
> case, could you at least add a comment here to call out as a tech debt
> so that it can be addressed in the future, if not now?

I guess we can remove the hidden dependency between en_lflow and en_bfd_sync.
It is enough to create a bpf_connection map in bfd_table_sync() (as you
suggested for stale bfd connections) and use it as input for en_lflow_run().
Doing so we have a clear dependency between en_lflow and en_bfd_sync nodes and
at the same time we can get rid of has_bfd field in ovn_por struct.
What do you think? I will fix it in v11.

> 
> > +    engine_add_input(&en_lflow, &en_route_policies, NULL);
> > +    engine_add_input(&en_lflow, &en_static_routes, NULL);
> >      engine_add_input(&en_lflow, &en_global_config,
> >                       node_global_config_handler);
> >      engine_add_input(&en_lflow, &en_northd, lflow_northd_handler);
> > diff --git a/northd/northd.c b/northd/northd.c
> > index a8a0b6f94..dad8d4069 100644
> > --- a/northd/northd.c
> > +++ b/northd/northd.c
> > @@ -9702,11 +9702,47 @@ build_lswitch_ip_unicast_lookup_for_nats(
> >  struct bfd_entry {
> >      struct hmap_node hmap_node;
> >
> > +    const struct nbrec_bfd *nb_bt;
> >      const struct sbrec_bfd *sb_bt;
> >
> > -    bool ref;
> > +    char *logical_port;
> > +    char *dst_ip;
> > +    char *status;
> > +    bool stale;
> >  };
> >

[...]

> 
> I think this comment is a little misleading. In this function we don't
> really need to write anything to the bfd_connections or even the
> bfd_map. The bfd_map is temporary and its only purpose is to record
> the stale entries so that they can be handled at the end of this
> function. The only field that is updated is the "stale". I think the
> "stale" field can be removed from the structure. We can instead do
> something similar but slightly more efficient here. We still need a
> temporary hmap, and initialized here by copying the whole
> bfd_connections entries. But in the next loop NBREC_BFD_TABLE_FOR_EACH
> we remove the entry because it is not stale. In the last loop it will
> only contain stale entries that need to be handled, so there is no
> need to maintain the "stale" status. What do you think?

To fix the hidden dependency between en_lflow and en_bfd_sync we need to keep
this map. Agree?

Regards,
Lorenzo

> 
> Thanks,
> Han
> 
> > +        struct bfd_entry *e = bfd_alloc_entry(&bfd_map, bfd_e->logical_port,
> > +                                              bfd_e->dst_ip, bfd_e->status);
> > +        e->stale = true;
> > +        e->nb_bt = bfd_e->nb_bt;
> > +        e->sb_bt = bfd_e->sb_bt;
> > +
> > +        /* we need to check if this entry is even in the BFD nb db table */
> > +        if (bfd_e->sb_bt) {
> > +            bitmap_set1(bfd_src_ports,
> > +                        bfd_e->sb_bt->src_port - BFD_UDP_SRC_PORT_START);
> > +        }
> >      }
> >
> >      const struct nbrec_bfd *nb_bt;
> >      NBREC_BFD_TABLE_FOR_EACH (nb_bt, nbrec_bfd_table) {
> > -        if (!nb_bt->status) {
> > -            /* default state is admin_down */
> > -            nbrec_bfd_set_status(nb_bt, "admin_down");
> > +        bfd_e = bfd_port_lookup(&bfd_map, nb_bt->logical_port, nb_bt->dst_ip);
> > +        if (!bfd_e) {
> > +            continue;
> >          }
> >
> >          struct ovn_port *op = ovn_port_find(lr_ports, nb_bt->logical_port);
> > -        bfd_e = bfd_port_lookup(&sb_only, nb_bt->logical_port, nb_bt->dst_ip);
> > -        if (!bfd_e) {
> > +        if (!op || !op->sb) {
> > +            /* skip not bounded ports */
> > +            continue;
> > +        }
> > +        op->has_bfd = true;
> > +
> > +        nbrec_bfd_set_status(nb_bt,
> > +                             bfd_get_connection_status(nb_bt,
> > +                                                       rp_bfd_connections,
> > +                                                       sr_bfd_connections));
> > +        if (!bfd_e->sb_bt) {
> >              int udp_src = bfd_get_unused_port(bfd_src_ports);
> >              if (udp_src < 0) {
> >                  continue;
> >              }
> >
> > -            sb_bt = sbrec_bfd_insert(ovnsb_txn);
> > +            /* Add entry to bfd sb table. */
> > +            const struct sbrec_bfd *sb_bt = sbrec_bfd_insert(ovnsb_txn);
> >              sbrec_bfd_set_logical_port(sb_bt, nb_bt->logical_port);
> >              sbrec_bfd_set_dst_ip(sb_bt, nb_bt->dst_ip);
> >              sbrec_bfd_set_disc(sb_bt, 1 + random_uint32());
> >              sbrec_bfd_set_src_port(sb_bt, udp_src);
> >              sbrec_bfd_set_status(sb_bt, nb_bt->status);
> > -            if (op && op->sb && op->sb->chassis) {
> > +            if (op->sb->chassis) {
> >                  sbrec_bfd_set_chassis_name(sb_bt, op->sb->chassis->name);
> >              }
> >
> > @@ -9873,37 +9925,62 @@ build_bfd_table(struct ovsdb_idl_txn *ovnsb_txn,
> >                      nbrec_bfd_set_status(nb_bt, bfd_e->sb_bt->status);
> >                  }
> >              }
> > +
> >              build_bfd_update_sb_conf(nb_bt, bfd_e->sb_bt);
> > -            if (op && op->sb && op->sb->chassis &&
> > -                strcmp(op->sb->chassis->name, bfd_e->sb_bt->chassis_name)) {
> > +            if (op->sb->chassis && !strcmp(op->sb->chassis->name,
> > +                                           bfd_e->sb_bt->chassis_name)) {
> >                  sbrec_bfd_set_chassis_name(bfd_e->sb_bt,
> >                                             op->sb->chassis->name);
> >              }
> > -
> > -            hmap_remove(&sb_only, &bfd_e->hmap_node);
> > -            bfd_e->ref = false;
> > -            hash = hash_string(bfd_e->sb_bt->dst_ip, 0);
> > -            hash = hash_string(bfd_e->sb_bt->logical_port, hash);
> > -            hmap_insert(bfd_connections, &bfd_e->hmap_node, hash);
> >          }
> > +        bfd_e->stale = false;
> > +    }
> >
> > -        if (op) {
> > -            op->has_bfd = true;
> > +    HMAP_FOR_EACH_POP (bfd_e, hmap_node, &bfd_map) {
> > +        if (bfd_e->stale) {
> > +            struct ovn_port *op = ovn_port_find(lr_ports, bfd_e->logical_port);
> > +            if (op) {
> > +                op->has_bfd = false;
> > +            }
> > +            sbrec_bfd_delete(bfd_e->sb_bt);
> >          }
> > +        bfd_erase_entry(bfd_e);
> >      }
> > +    hmap_destroy(&bfd_map);
> > +
> > +    bitmap_free(bfd_src_ports);
> > +}
> > +
> > +void
> > +build_bfd_map(const struct nbrec_bfd_table *nbrec_bfd_table,
> > +              const struct sbrec_bfd_table *sbrec_bfd_table,
> > +              struct hmap *bfd_connections)
> > +{
> > +    struct bfd_entry *bfd_e;
> >
> > -    HMAP_FOR_EACH_POP (bfd_e, hmap_node, &sb_only) {
> > -        struct ovn_port *op = ovn_port_find(lr_ports,
> > -                                            bfd_e->sb_bt->logical_port);
> > -        if (op) {
> > -            op->has_bfd = false;
> > +    /* align bfd_map to sb db */
> > +    const struct sbrec_bfd *sb_bt;
> > +    SBREC_BFD_TABLE_FOR_EACH (sb_bt, sbrec_bfd_table) {
> > +        bfd_e = bfd_port_lookup(bfd_connections, sb_bt->logical_port,
> > +                                sb_bt->dst_ip);
> > +        if (!bfd_e) {
> > +            bfd_e = bfd_alloc_entry(bfd_connections, sb_bt->logical_port,
> > +                                    sb_bt->dst_ip,  sb_bt->status);
> >          }
> > -        sbrec_bfd_delete(bfd_e->sb_bt);
> > -        free(bfd_e);
> > +        bfd_e->sb_bt = sb_bt;
> >      }
> > -    hmap_destroy(&sb_only);
> >
> > -    bitmap_free(bfd_src_ports);
> > +    const struct nbrec_bfd *nb_bt;
> > +    NBREC_BFD_TABLE_FOR_EACH (nb_bt, nbrec_bfd_table) {
> > +        bfd_e = bfd_port_lookup(bfd_connections, nb_bt->logical_port,
> > +                                nb_bt->dst_ip);
> > +        if (!bfd_e) {
> > +            /* brand new entry. */
> > +            bfd_e = bfd_alloc_entry(bfd_connections, nb_bt->logical_port,
> > +                                    nb_bt->dst_ip, "admin_down");
> > +        }
> > +        bfd_e->nb_bt = nb_bt;
> > +    }
> >  }
> >
> >  /* Returns a string of the IP address of the router port 'op' that
> > @@ -9941,17 +10018,13 @@ get_outport_for_routing_policy_nexthop(struct ovn_datapath *od,
> >      return NULL;
> >  }
> >
> > -static struct ovs_mutex bfd_lock = OVS_MUTEX_INITIALIZER;
> > -
> > -static bool check_bfd_state(
> > -        const struct nbrec_logical_router_policy *rule,
> > -        const struct hmap *bfd_connections,
> > -        struct ovn_port *out_port,
> > -        const char *nexthop)
> > +static bool check_bfd_state(const struct nbrec_logical_router_policy *rule,
> > +                            struct ovn_port *out_port, const char *nexthop,
> > +                            struct hmap *bfd_connections,
> > +                            struct hmap *bfd_active_connections)
> >  {
> >      struct in6_addr nexthop_v6;
> >      bool is_nexthop_v6 = ipv6_parse(nexthop, &nexthop_v6);
> > -    bool ret = true;
> >
> >      for (size_t i = 0; i < rule->n_bfd_sessions; i++) {
> >          /* Check if there is a BFD session associated to the reroute
> > @@ -9976,39 +10049,48 @@ static bool check_bfd_state(
> >          struct bfd_entry *bfd_e = bfd_port_lookup(bfd_connections,
> >                                                    nb_bt->logical_port,
> >                                                    nb_bt->dst_ip);
> > -        ovs_mutex_lock(&bfd_lock);
> > -        if (bfd_e) {
> > -            bfd_e->ref = true;
> > +        if (!bfd_e) {
> > +            continue;
> >          }
> >
> > -        if (!strcmp(nb_bt->status, "admin_down")) {
> > -            nbrec_bfd_set_status(nb_bt, "down");
> > +        /* This route policy is linked to an active bfd session. */
> > +        struct bfd_entry *bfd_rp = bfd_port_lookup(bfd_active_connections,
> > +                                                   nb_bt->logical_port,
> > +                                                   nb_bt->dst_ip);
> > +        if (!bfd_rp) {
> > +            bfd_rp = bfd_alloc_entry(bfd_active_connections,
> > +                                     nb_bt->logical_port, nb_bt->dst_ip,
> > +                                     bfd_e->status);
> >          }
> >
> > -        ret = strcmp(nb_bt->status, "down");
> > -        ovs_mutex_unlock(&bfd_lock);
> > -        break;
> > +        if (!strcmp(bfd_e->status, "admin_down")) {
> > +            bfd_set_status(bfd_rp, "down");
> > +        }
> > +
> > +        return strcmp(bfd_rp->status, "down");
> >      }
> >
> > -    return ret;
> > +    return true;
> >  }
> >
> >  static void
> >  build_routing_policy_flow(struct lflow_table *lflows, struct ovn_datapath *od,
> > -                          const struct hmap *lr_ports,
> > -                          const struct nbrec_logical_router_policy *rule,
> > -                          const struct hmap *bfd_connections,
> > +                          const struct hmap *lr_ports, struct route_policy *rp,
> >                            const struct ovsdb_idl_row *stage_hint,
> >                            struct lflow_ref *lflow_ref)
> >  {
> > +    const struct nbrec_logical_router_policy *rule = rp->rule;
> >      struct ds match = DS_EMPTY_INITIALIZER;
> >      struct ds actions = DS_EMPTY_INITIALIZER;
> >
> >      if (!strcmp(rule->action, "reroute")) {
> >          ovs_assert(rule->n_nexthops <= 1);
> >
> > -        char *nexthop =
> > -            (rule->n_nexthops == 1 ? rule->nexthops[0] : rule->nexthop);
> > +        if (!rp->n_valid_nexthops) {
> > +            return;
> > +        }
> > +
> > +        char *nexthop = rp->valid_nexthops[0];
> >          struct ovn_port *out_port = get_outport_for_routing_policy_nexthop(
> >               od, lr_ports, rule->priority, nexthop);
> >          if (!out_port) {
> > @@ -10024,10 +10106,6 @@ build_routing_policy_flow(struct lflow_table *lflows, struct ovn_datapath *od,
> >              return;
> >          }
> >
> > -        if (!check_bfd_state(rule, bfd_connections, out_port, nexthop)) {
> > -            return;
> > -        }
> > -
> >          uint32_t pkt_mark = smap_get_uint(&rule->options, "pkt_mark", 0);
> >          if (pkt_mark) {
> >              ds_put_format(&actions, "pkt.mark = %u; ", pkt_mark);
> > @@ -10070,19 +10148,18 @@ static void
> >  build_ecmp_routing_policy_flows(struct lflow_table *lflows,
> >                                  struct ovn_datapath *od,
> >                                  const struct hmap *lr_ports,
> > -                                const struct nbrec_logical_router_policy *rule,
> > -                                const struct hmap *bfd_connections,
> > +                                struct route_policy *rp,
> >                                  uint16_t ecmp_group_id,
> >                                  struct lflow_ref *lflow_ref)
> >  {
> > -    ovs_assert(rule->n_nexthops > 1);
> > -
> >      bool nexthops_is_ipv4 = true;
> > +    const struct nbrec_logical_router_policy *rule = rp->rule;
> > +    ovs_assert(rule->n_nexthops > 1);
> >
> >      /* Check that all the nexthops belong to the same addr family before
> >       * adding logical flows. */
> > -    for (uint16_t i = 0; i < rule->n_nexthops; i++) {
> > -        bool is_ipv4 = strchr(rule->nexthops[i], '.') ? true : false;
> > +    for (uint16_t i = 0; i < rp->n_valid_nexthops; i++) {
> > +        bool is_ipv4 = strchr(rp->valid_nexthops[i], '.') ? true : false;
> >
> >          if (i == 0) {
> >              nexthops_is_ipv4 = is_ipv4;
> > @@ -10093,7 +10170,7 @@ build_ecmp_routing_policy_flows(struct lflow_table *lflows,
> >              VLOG_WARN_RL(&rl, "nexthop [%s] of the router policy with "
> >                           "the match [%s] do not belong to the same address "
> >                           "family as other next hops",
> > -                         rule->nexthops[i], rule->match);
> > +                         rp->valid_nexthops[i], rule->match);
> >              return;
> >          }
> >      }
> > @@ -10101,40 +10178,30 @@ build_ecmp_routing_policy_flows(struct lflow_table *lflows,
> >      struct ds match = DS_EMPTY_INITIALIZER;
> >      struct ds actions = DS_EMPTY_INITIALIZER;
> >
> > -    size_t *valid_nexthops = xcalloc(rule->n_nexthops, sizeof *valid_nexthops);
> > -    size_t n_valid_nexthops = 0;
> > -
> > -    for (size_t i = 0; i < rule->n_nexthops; i++) {
> > +    for (size_t i = 0; i < rp->n_valid_nexthops; i++) {
> >          struct ovn_port *out_port = get_outport_for_routing_policy_nexthop(
> > -             od, lr_ports, rule->priority, rule->nexthops[i]);
> > +             od, lr_ports, rule->priority, rp->valid_nexthops[i]);
> >          if (!out_port) {
> >              goto cleanup;
> >          }
> >
> >          const char *lrp_addr_s =
> > -            find_lrp_member_ip(out_port, rule->nexthops[i]);
> > +            find_lrp_member_ip(out_port, rp->valid_nexthops[i]);
> >          if (!lrp_addr_s) {
> >              static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 1);
> >              VLOG_WARN_RL(&rl, "lrp_addr not found for routing policy "
> >                              " priority %"PRId64" nexthop %s",
> > -                            rule->priority, rule->nexthops[i]);
> > +                            rule->priority, rp->valid_nexthops[i]);
> >              goto cleanup;
> >          }
> >
> > -        if (!check_bfd_state(rule, bfd_connections, out_port,
> > -                             rule->nexthops[i])) {
> > -            continue;
> > -        }
> > -
> > -        valid_nexthops[n_valid_nexthops++] = i + 1;
> > -
> >          ds_clear(&actions);
> >          uint32_t pkt_mark = smap_get_uint(&rule->options, "pkt_mark", 0);
> >          if (pkt_mark) {
> >              ds_put_format(&actions, "pkt.mark = %u; ", pkt_mark);
> >          }
> >
> > -        bool is_ipv4 = strchr(rule->nexthops[i], '.') ? true : false;
> > +        bool is_ipv4 = strchr(rp->valid_nexthops[i], '.') ? true : false;
> >
> >          ds_put_format(&actions, "%s = %s; "
> >                        "%s = %s; "
> > @@ -10143,7 +10210,7 @@ build_ecmp_routing_policy_flows(struct lflow_table *lflows,
> >                        "flags.loopback = 1; "
> >                        "next;",
> >                        is_ipv4 ? REG_NEXT_HOP_IPV4 : REG_NEXT_HOP_IPV6,
> > -                      rule->nexthops[i],
> > +                      rp->valid_nexthops[i],
> >                        is_ipv4 ? REG_SRC_IPV4 : REG_SRC_IPV6,
> >                        lrp_addr_s,
> >                        out_port->lrp_networks.ea_s,
> > @@ -10159,37 +10226,30 @@ build_ecmp_routing_policy_flows(struct lflow_table *lflows,
> >                                  lflow_ref);
> >      }
> >
> > -    if (!n_valid_nexthops) {
> > -        goto cleanup;
> > -    }
> > -
> >      ds_clear(&actions);
> > -    if (n_valid_nexthops > 1) {
> > +    if (rp->n_valid_nexthops > 1) {
> >          ds_put_format(&actions, "%s = %"PRIu16
> >                        "; %s = select(", REG_ECMP_GROUP_ID, ecmp_group_id,
> >                        REG_ECMP_MEMBER_ID);
> >
> > -        for (size_t i = 0; i < n_valid_nexthops; i++) {
> > +        for (size_t i = 0; i < rp->n_valid_nexthops; i++) {
> >              if (i > 0) {
> >                  ds_put_cstr(&actions, ", ");
> >              }
> >
> > -            ds_put_format(&actions, "%"PRIuSIZE, valid_nexthops[i]);
> > +            ds_put_format(&actions, "%"PRIuSIZE, i + 1);
> >          }
> >          ds_put_cstr(&actions, ");");
> >      } else {
> >          ds_put_format(&actions, "%s = %"PRIu16
> > -                      "; %s = %"PRIuSIZE"; next;", REG_ECMP_GROUP_ID,
> > -                      ecmp_group_id, REG_ECMP_MEMBER_ID,
> > -                      valid_nexthops[0]);
> > +                      "; %s = 1; next;", REG_ECMP_GROUP_ID,
> > +                      ecmp_group_id, REG_ECMP_MEMBER_ID);
> >      }
> >      ovn_lflow_add_with_hint(lflows, od, S_ROUTER_IN_POLICY,
> >                              rule->priority, rule->match,
> >                              ds_cstr(&actions), &rule->header_,
> >                              lflow_ref);
> > -
> >  cleanup:
> > -    free(valid_nexthops);
> >      ds_destroy(&match);
> >      ds_destroy(&actions);
> >  }
> > @@ -10214,7 +10274,7 @@ route_table_add(struct simap *route_tables, const char *route_table_name)
> >      return rtb_id;
> >  }
> >
> > -static uint32_t
> > +uint32_t
> >  get_route_table_id(struct simap *route_tables, const char *route_table_name)
> >  {
> >      if (!route_table_name || !route_table_name[0]) {
> > @@ -10255,18 +10315,6 @@ build_route_table_lflow(struct ovn_datapath *od, struct lflow_table *lflows,
> >      ds_destroy(&actions);
> >  }
> >
> > -struct parsed_route {
> > -    struct ovs_list list_node;
> > -    struct in6_addr prefix;
> > -    unsigned int plen;
> > -    bool is_src_route;
> > -    uint32_t route_table_id;
> > -    uint32_t hash;
> > -    const struct nbrec_logical_router_static_route *route;
> > -    bool ecmp_symmetric_reply;
> > -    bool is_discard_route;
> > -};
> > -
> >  static uint32_t
> >  route_hash(struct parsed_route *route)
> >  {
> > @@ -10281,11 +10329,53 @@ find_static_route_outport(struct ovn_datapath *od, const struct hmap *lr_ports,
> >
> >  /* Parse and validate the route. Return the parsed route if successful.
> >   * Otherwise return NULL. */
> > +
> >  static struct parsed_route *
> > +parsed_route_lookup(struct hmap *routes, size_t hash,
> > +                    struct parsed_route *new_pr)
> > +{
> > +    struct parsed_route *pr;
> > +    HMAP_FOR_EACH_WITH_HASH (pr, key_node, hash, routes) {
> > +        if (pr->plen != new_pr->plen) {
> > +            continue;
> > +        }
> > +
> > +        if (memcmp(&pr->prefix, &new_pr->prefix, sizeof(struct in6_addr))) {
> > +            continue;
> > +        }
> > +
> > +        if (pr->is_src_route != new_pr->is_src_route) {
> > +            continue;
> > +        }
> > +
> > +        if (pr->route_table_id != new_pr->route_table_id) {
> > +            continue;
> > +        }
> > +
> > +        if (pr->route != new_pr->route) {
> > +            continue;
> > +        }
> > +
> > +        if (pr->ecmp_symmetric_reply != new_pr->ecmp_symmetric_reply) {
> > +            continue;
> > +        }
> > +
> > +        if (pr->is_discard_route != new_pr->is_discard_route) {
> > +            continue;
> > +        }
> > +
> > +        return pr;
> > +    }
> > +
> > +    return NULL;
> > +}
> > +
> > +static void
> >  parsed_routes_add(struct ovn_datapath *od, const struct hmap *lr_ports,
> > -                  struct ovs_list *routes, struct simap *route_tables,
> >                    const struct nbrec_logical_router_static_route *route,
> > -                  const struct hmap *bfd_connections)
> > +                  struct hmap *bfd_connections,
> > +                  struct hmap *routes, struct simap *route_tables,
> > +                  struct hmap *bfd_active_connections)
> >  {
> >      /* Verify that the next hop is an IP address with an all-ones mask. */
> >      struct in6_addr nexthop;
> > @@ -10298,7 +10388,7 @@ parsed_routes_add(struct ovn_datapath *od, const struct hmap *lr_ports,
> >              VLOG_WARN_RL(&rl, "bad 'nexthop' %s in static route "
> >                           UUID_FMT, route->nexthop,
> >                           UUID_ARGS(&route->header_.uuid));
> > -            return NULL;
> > +            return;
> >          }
> >          if ((IN6_IS_ADDR_V4MAPPED(&nexthop) && plen != 32) ||
> >              (!IN6_IS_ADDR_V4MAPPED(&nexthop) && plen != 128)) {
> > @@ -10306,7 +10396,7 @@ parsed_routes_add(struct ovn_datapath *od, const struct hmap *lr_ports,
> >              VLOG_WARN_RL(&rl, "bad next hop mask %s in static route "
> >                           UUID_FMT, route->nexthop,
> >                           UUID_ARGS(&route->header_.uuid));
> > -            return NULL;
> > +            return;
> >          }
> >      }
> >
> > @@ -10317,7 +10407,7 @@ parsed_routes_add(struct ovn_datapath *od, const struct hmap *lr_ports,
> >          VLOG_WARN_RL(&rl, "bad 'ip_prefix' %s in static route "
> >                       UUID_FMT, route->ip_prefix,
> >                       UUID_ARGS(&route->header_.uuid));
> > -        return NULL;
> > +        return;
> >      }
> >
> >      /* Verify that ip_prefix and nexthop have same address familiy. */
> > @@ -10328,7 +10418,7 @@ parsed_routes_add(struct ovn_datapath *od, const struct hmap *lr_ports,
> >                           " %s and 'nexthop' %s in static route "UUID_FMT,
> >                           route->ip_prefix, route->nexthop,
> >                           UUID_ARGS(&route->header_.uuid));
> > -            return NULL;
> > +            return;
> >          }
> >      }
> >
> > @@ -10337,52 +10427,88 @@ parsed_routes_add(struct ovn_datapath *od, const struct hmap *lr_ports,
> >          !find_static_route_outport(od, lr_ports, route,
> >                                     IN6_IS_ADDR_V4MAPPED(&prefix),
> >                                     NULL, NULL)) {
> > -        return NULL;
> > +        return;
> >      }
> >
> >      const struct nbrec_bfd *nb_bt = route->bfd;
> >      if (nb_bt && !strcmp(nb_bt->dst_ip, route->nexthop)) {
> > -        struct bfd_entry *bfd_e;
> > +        struct bfd_entry *bfd_e = bfd_port_lookup(bfd_connections,
> > +                                                  nb_bt->logical_port,
> > +                                                  nb_bt->dst_ip);
> > +        if (!bfd_e) {
> > +            return;
> > +        }
> >
> > -        bfd_e = bfd_port_lookup(bfd_connections, nb_bt->logical_port,
> > -                                nb_bt->dst_ip);
> > -        ovs_mutex_lock(&bfd_lock);
> > -        if (bfd_e) {
> > -            bfd_e->ref = true;
> > +        /* This static route is linked to an active bfd session. */
> > +        struct bfd_entry *bfd_sr = bfd_port_lookup(bfd_active_connections,
> > +                                                   nb_bt->logical_port,
> > +                                                   nb_bt->dst_ip);
> > +        if (!bfd_sr) {
> > +            bfd_sr = bfd_alloc_entry(bfd_active_connections,
> > +                                     nb_bt->logical_port, nb_bt->dst_ip,
> > +                                     bfd_e->status);
> >          }
> >
> > -        if (!strcmp(nb_bt->status, "admin_down")) {
> > -            nbrec_bfd_set_status(nb_bt, "down");
> > +        if (!strcmp(bfd_e->status, "admin_down")) {
> > +            bfd_set_status(bfd_sr, "down");
> >          }
> >
> > -        if (!strcmp(nb_bt->status, "down")) {
> > -            ovs_mutex_unlock(&bfd_lock);
> > -            return NULL;
> > +
> > +        if (!strcmp(bfd_sr->status, "down")) {
> > +            return;
> >          }
> > -        ovs_mutex_unlock(&bfd_lock);
> >      }
> >
> > -    struct parsed_route *pr = xzalloc(sizeof *pr);
> > -    pr->prefix = prefix;
> > -    pr->plen = plen;
> > -    pr->route_table_id = get_route_table_id(route_tables, route->route_table);
> > -    pr->is_src_route = (route->policy && !strcmp(route->policy,
> > -                                                 "src-ip"));
> > -    pr->hash = route_hash(pr);
> > -    pr->route = route;
> > -    pr->ecmp_symmetric_reply = smap_get_bool(&route->options,
> > -                                             "ecmp_symmetric_reply", false);
> > -    pr->is_discard_route = is_discard_route;
> > -    ovs_list_insert(routes, &pr->list_node);
> > -    return pr;
> > +    struct parsed_route *new_pr = xzalloc(sizeof *new_pr);
> > +    new_pr->prefix = prefix;
> > +    new_pr->plen = plen;
> > +    new_pr->route_table_id = get_route_table_id(route_tables,
> > +                                                route->route_table);
> > +    new_pr->is_src_route = (route->policy &&
> > +                            !strcmp(route->policy, "src-ip"));
> > +    new_pr->hash = route_hash(new_pr);
> > +    new_pr->route = route;
> > +    new_pr->nbr = od->nbr;
> > +    new_pr->ecmp_symmetric_reply = smap_get_bool(&route->options,
> > +                                                 "ecmp_symmetric_reply",
> > +                                                 false);
> > +    new_pr->is_discard_route = is_discard_route;
> > +
> > +    size_t hash = uuid_hash(&od->key);
> > +    struct parsed_route *pr = parsed_route_lookup(routes, hash, new_pr);
> > +    if (!pr) {
> > +        hmap_insert(routes, &new_pr->key_node, hash);
> > +    } else {
> > +        pr->stale = false;
> > +        free(new_pr);
> > +    }
> >  }
> >
> > -static void
> > -parsed_routes_destroy(struct ovs_list *routes)
> > +void
> > +build_parsed_routes(struct ovn_datapath *od, const struct hmap *lr_ports,
> > +                    struct hmap *bfd_connections, struct hmap *routes,
> > +                    struct simap *route_tables,
> > +                    struct hmap *bfd_active_connections)
> >  {
> >      struct parsed_route *pr;
> > -    LIST_FOR_EACH_SAFE (pr, list_node, routes) {
> > -        ovs_list_remove(&pr->list_node);
> > +    HMAP_FOR_EACH (pr, key_node, routes) {
> > +        if (pr->nbr == od->nbr) {
> > +            pr->stale = true;
> > +        }
> > +    }
> > +
> > +    for (int i = 0; i < od->nbr->n_static_routes; i++) {
> > +        parsed_routes_add(od, lr_ports, od->nbr->static_routes[i],
> > +                          bfd_connections, routes, route_tables,
> > +                          bfd_active_connections);
> > +    }
> > +
> > +    HMAP_FOR_EACH_SAFE (pr, key_node, routes) {
> > +        if (!pr->stale) {
> > +            continue;
> > +        }
> > +
> > +        hmap_remove(routes, &pr->key_node);
> >          free(pr);
> >      }
> >  }
> > @@ -12684,8 +12810,8 @@ build_ip_routing_flows_for_lrp(
> >  static void
> >  build_static_route_flows_for_lrouter(
> >          struct ovn_datapath *od, struct lflow_table *lflows,
> > -        const struct hmap *lr_ports, const struct hmap *bfd_connections,
> > -        struct lflow_ref *lflow_ref)
> > +        const struct hmap *lr_ports, struct hmap *parsed_routes,
> > +        struct simap *route_tables, struct lflow_ref *lflow_ref)
> >  {
> >      ovs_assert(od->nbr);
> >      ovn_lflow_add_default_drop(lflows, od, S_ROUTER_IN_IP_ROUTING_ECMP,
> > @@ -12698,22 +12824,16 @@ build_static_route_flows_for_lrouter(
> >
> >      struct hmap ecmp_groups = HMAP_INITIALIZER(&ecmp_groups);
> >      struct hmap unique_routes = HMAP_INITIALIZER(&unique_routes);
> > -    struct ovs_list parsed_routes = OVS_LIST_INITIALIZER(&parsed_routes);
> > -    struct simap route_tables = SIMAP_INITIALIZER(&route_tables);
> >      struct ecmp_groups_node *group;
> >
> >      for (int i = 0; i < od->nbr->n_ports; i++) {
> >          build_route_table_lflow(od, lflows, od->nbr->ports[i],
> > -                                &route_tables, lflow_ref);
> > +                                route_tables, lflow_ref);
> >      }
> >
> > -    for (int i = 0; i < od->nbr->n_static_routes; i++) {
> > -        struct parsed_route *route =
> > -            parsed_routes_add(od, lr_ports, &parsed_routes, &route_tables,
> > -                              od->nbr->static_routes[i], bfd_connections);
> > -        if (!route) {
> > -            continue;
> > -        }
> > +    struct parsed_route *route;
> > +    HMAP_FOR_EACH_WITH_HASH (route, key_node, uuid_hash(&od->key),
> > +                             parsed_routes) {
> >          group = ecmp_groups_find(&ecmp_groups, route);
> >          if (group) {
> >              ecmp_groups_add_route(group, route);
> > @@ -12741,8 +12861,6 @@ build_static_route_flows_for_lrouter(
> >      }
> >      ecmp_groups_destroy(&ecmp_groups);
> >      unique_routes_destroy(&unique_routes);
> > -    parsed_routes_destroy(&parsed_routes);
> > -    simap_destroy(&route_tables);
> >  }
> >
> >  /* IP Multicast lookup. Here we set the output port, adjust TTL and
> > @@ -12849,6 +12967,115 @@ build_mcast_lookup_flows_for_lrouter(
> >      }
> >  }
> >
> > +static struct route_policy *
> > +route_policies_lookup(struct hmap *route_policies, size_t hash,
> > +                      struct route_policy *new_rp)
> > +{
> > +    struct route_policy *rp;
> > +    HMAP_FOR_EACH_WITH_HASH (rp, key_node, hash, route_policies) {
> > +        if (rp->rule != new_rp->rule) {
> > +            continue;
> > +        }
> > +
> > +        if (rp->n_valid_nexthops != new_rp->n_valid_nexthops) {
> > +            continue;
> > +        }
> > +
> > +        size_t i;
> > +        for (i = 0; i < new_rp->n_valid_nexthops; i++) {
> > +            size_t j;
> > +
> > +            for (j = 0; j < rp->n_valid_nexthops; j++) {
> > +                if (!strcmp(new_rp->valid_nexthops[i],
> > +                            rp->valid_nexthops[j])) {
> > +                    break;
> > +                }
> > +            }
> > +
> > +            if (j == rp->n_valid_nexthops) {
> > +                break;
> > +            }
> > +        }
> > +
> > +        if (i == new_rp->n_valid_nexthops) {
> > +            return rp;
> > +        }
> > +    }
> > +
> > +    return NULL;
> > +}
> > +
> > +void
> > +build_route_policies(struct ovn_datapath *od, struct hmap *lr_ports,
> > +                     struct hmap *bfd_connections,
> > +                     struct hmap *route_policies,
> > +                     struct hmap *bfd_active_connections)
> > +{
> > +    struct route_policy *rp;
> > +
> > +    HMAP_FOR_EACH (rp, key_node, route_policies) {
> > +        if (rp->nbr == od->nbr) {
> > +            rp->stale = true;
> > +        }
> > +    }
> > +
> > +    for (int i = 0; i < od->nbr->n_policies; i++) {
> > +        const struct nbrec_logical_router_policy *rule = od->nbr->policies[i];
> > +        size_t n_valid_nexthops = 0;
> > +        char **valid_nexthops = NULL;
> > +
> > +        if (!strcmp(rule->action, "reroute")) {
> > +            size_t n_nexthops = rule->n_nexthops ? rule->n_nexthops : 1;
> > +
> > +            valid_nexthops = xcalloc(n_nexthops, sizeof *valid_nexthops);
> > +            for (size_t j = 0; j < n_nexthops; j++) {
> > +                char *nexthop = rule->n_nexthops
> > +                    ? rule->nexthops[j] : rule->nexthop;
> > +                struct ovn_port *out_port =
> > +                    get_outport_for_routing_policy_nexthop(
> > +                            od, lr_ports, rule->priority, nexthop);
> > +                if (!out_port || !check_bfd_state(rule, out_port, nexthop,
> > +                                                  bfd_connections,
> > +                                                  bfd_active_connections)) {
> > +                    continue;
> > +                }
> > +                valid_nexthops[n_valid_nexthops++] = nexthop;
> > +            }
> > +
> > +            if (!n_valid_nexthops) {
> > +                free(valid_nexthops);
> > +                continue;
> > +            }
> > +        }
> > +
> > +        struct route_policy *new_rp = xzalloc(sizeof *new_rp);
> > +        new_rp->rule = rule;
> > +        new_rp->n_valid_nexthops = n_valid_nexthops;
> > +        new_rp->valid_nexthops = valid_nexthops;
> > +        new_rp->nbr = od->nbr;
> > +
> > +        size_t hash = uuid_hash(&od->key);
> > +        rp = route_policies_lookup(route_policies, hash, new_rp);
> > +        if (!rp) {
> > +            hmap_insert(route_policies, &new_rp->key_node, hash);
> > +        } else {
> > +            rp->stale = false;
> > +            free(valid_nexthops);
> > +            free(new_rp);
> > +        }
> > +    }
> > +
> > +    HMAP_FOR_EACH_SAFE (rp, key_node, route_policies) {
> > +        if (!rp->stale) {
> > +            continue;
> > +        }
> > +
> > +        hmap_remove(route_policies, &rp->key_node);
> > +        free(rp->valid_nexthops);
> > +        free(rp);
> > +    }
> > +}
> > +
> >  /* Logical router ingress table POLICY: Policy.
> >   *
> >   * A packet that arrives at this table is an IP packet that should be
> > @@ -12862,7 +13089,7 @@ static void
> >  build_ingress_policy_flows_for_lrouter(
> >          struct ovn_datapath *od, struct lflow_table *lflows,
> >          const struct hmap *lr_ports,
> > -        const struct hmap *bfd_connections,
> > +        struct hmap *route_policies,
> >          struct lflow_ref *lflow_ref)
> >  {
> >      ovs_assert(od->nbr);
> > @@ -12879,21 +13106,20 @@ build_ingress_policy_flows_for_lrouter(
> >
> >      /* Convert routing policies to flows. */
> >      uint16_t ecmp_group_id = 1;
> > -    for (int i = 0; i < od->nbr->n_policies; i++) {
> > -        const struct nbrec_logical_router_policy *rule
> > -            = od->nbr->policies[i];
> > +    struct route_policy *rp;
> > +    HMAP_FOR_EACH_WITH_HASH (rp, key_node, uuid_hash(&od->key),
> > +                             route_policies) {
> > +        const struct nbrec_logical_router_policy *rule = rp->rule;
> >          bool is_ecmp_reroute =
> >              (!strcmp(rule->action, "reroute") && rule->n_nexthops > 1);
> >
> >          if (is_ecmp_reroute) {
> > -            build_ecmp_routing_policy_flows(lflows, od, lr_ports, rule,
> > -                                            bfd_connections, ecmp_group_id,
> > -                                            lflow_ref);
> > +            build_ecmp_routing_policy_flows(lflows, od, lr_ports, rp,
> > +                                            ecmp_group_id, lflow_ref);
> >              ecmp_group_id++;
> >          } else {
> > -            build_routing_policy_flow(lflows, od, lr_ports, rule,
> > -                                      bfd_connections, &rule->header_,
> > -                                      lflow_ref);
> > +            build_routing_policy_flow(lflows, od, lr_ports, rp,
> > +                                      &rule->header_, lflow_ref);
> >          }
> >      }
> >  }
> > @@ -15818,6 +16044,9 @@ struct lswitch_flow_build_info {
> >      struct ds actions;
> >      size_t thread_lflow_counter;
> >      const char *svc_monitor_mac;
> > +    struct hmap *parsed_routes;
> > +    struct hmap *route_policies;
> > +    struct simap *route_tables;
> >  };
> >
> >  /* Helper function to combine all lflow generation which is iterated by
> > @@ -15863,12 +16092,12 @@ build_lswitch_and_lrouter_iterate_by_lr(struct ovn_datapath *od,
> >      build_ND_RA_flows_for_lrouter(od, lsi->lflows, NULL);
> >      build_ip_routing_pre_flows_for_lrouter(od, lsi->lflows, NULL);
> >      build_static_route_flows_for_lrouter(od, lsi->lflows, lsi->lr_ports,
> > -                                         lsi->bfd_connections,
> > +                                         lsi->parsed_routes, lsi->route_tables,
> >                                           NULL);
> >      build_mcast_lookup_flows_for_lrouter(od, lsi->lflows, &lsi->match,
> >                                           &lsi->actions, NULL);
> >      build_ingress_policy_flows_for_lrouter(od, lsi->lflows, lsi->lr_ports,
> > -                                           lsi->bfd_connections, NULL);
> > +                                           lsi->route_policies, NULL);
> >      build_arp_resolve_flows_for_lrouter(od, lsi->lflows, NULL);
> >      build_check_pkt_len_flows_for_lrouter(od, lsi->lflows, lsi->lr_ports,
> >                                            &lsi->match, &lsi->actions,
> > @@ -16182,7 +16411,10 @@ build_lswitch_and_lrouter_flows(
> >      const struct hmap *svc_monitor_map,
> >      const struct hmap *bfd_connections,
> >      const struct chassis_features *features,
> > -    const char *svc_monitor_mac)
> > +    const char *svc_monitor_mac,
> > +    struct hmap *parsed_routes,
> > +    struct hmap *route_policies,
> > +    struct simap *route_tables)
> >  {
> >
> >      char *svc_check_match = xasprintf("eth.dst == %s", svc_monitor_mac);
> > @@ -16216,6 +16448,9 @@ build_lswitch_and_lrouter_flows(
> >              lsiv[index].svc_check_match = svc_check_match;
> >              lsiv[index].thread_lflow_counter = 0;
> >              lsiv[index].svc_monitor_mac = svc_monitor_mac;
> > +            lsiv[index].parsed_routes = parsed_routes;
> > +            lsiv[index].route_tables = route_tables;
> > +            lsiv[index].route_policies = route_policies;
> >              ds_init(&lsiv[index].match);
> >              ds_init(&lsiv[index].actions);
> >
> > @@ -16256,6 +16491,9 @@ build_lswitch_and_lrouter_flows(
> >              .features = features,
> >              .svc_check_match = svc_check_match,
> >              .svc_monitor_mac = svc_monitor_mac,
> > +            .parsed_routes = parsed_routes,
> > +            .route_tables = route_tables,
> > +            .route_policies = route_policies,
> >              .match = DS_EMPTY_INITIALIZER,
> >              .actions = DS_EMPTY_INITIALIZER,
> >          };
> > @@ -16417,7 +16655,10 @@ void build_lflows(struct ovsdb_idl_txn *ovnsb_txn,
> >                                      input_data->svc_monitor_map,
> >                                      input_data->bfd_connections,
> >                                      input_data->features,
> > -                                    input_data->svc_monitor_mac);
> > +                                    input_data->svc_monitor_mac,
> > +                                    input_data->parsed_routes,
> > +                                    input_data->route_policies,
> > +                                    input_data->route_tables);
> >
> >      if (parallelization_state == STATE_INIT_HASH_SIZES) {
> >          parallelization_state = STATE_USE_PARALLELIZATION;
> > @@ -17490,6 +17731,27 @@ northd_init(struct northd_data *data)
> >      init_northd_tracked_data(data);
> >  }
> >
> > +void
> > +route_policies_init(struct route_policies_data *data)
> > +{
> > +    hmap_init(&data->route_policies);
> > +    hmap_init(&data->bfd_active_connections);
> > +}
> > +
> > +void
> > +static_routes_init(struct static_routes_data *data)
> > +{
> > +    hmap_init(&data->parsed_routes);
> > +    simap_init(&data->route_tables);
> > +    hmap_init(&data->bfd_active_connections);
> > +}
> > +
> > +void
> > +bfd_init(struct bfd_data *data)
> > +{
> > +    hmap_init(&data->bfd_connections);
> > +}
> > +
> >  void
> >  northd_destroy(struct northd_data *data)
> >  {
> > @@ -17529,6 +17791,48 @@ northd_destroy(struct northd_data *data)
> >      destroy_northd_tracked_data(data);
> >  }
> >
> > +static void
> > +__bfd_destroy(struct hmap *bfd_connections)
> > +{
> > +    struct bfd_entry *bfd_e;
> > +
> > +    HMAP_FOR_EACH_POP (bfd_e, hmap_node, bfd_connections) {
> > +        bfd_erase_entry(bfd_e);
> > +    }
> > +    hmap_destroy(bfd_connections);
> > +}
> > +
> > +void
> > +bfd_destroy(struct bfd_data *data)
> > +{
> > +    __bfd_destroy(&data->bfd_connections);
> > +}
> > +
> > +void
> > +route_policies_destroy(struct route_policies_data *data)
> > +{
> > +    struct route_policy *rp;
> > +    HMAP_FOR_EACH_POP (rp, key_node, &data->route_policies) {
> > +        free(rp->valid_nexthops);
> > +        free(rp);
> > +    };
> > +    hmap_destroy(&data->route_policies);
> > +    __bfd_destroy(&data->bfd_active_connections);
> > +}
> > +
> > +void
> > +static_routes_destroy(struct static_routes_data *data)
> > +{
> > +    struct parsed_route *r;
> > +    HMAP_FOR_EACH_POP (r, key_node, &data->parsed_routes) {
> > +        free(r);
> > +    }
> > +    hmap_destroy(&data->parsed_routes);
> > +
> > +    simap_destroy(&data->route_tables);
> > +    __bfd_destroy(&data->bfd_active_connections);
> > +}
> > +
> >  void
> >  ovnnb_db_run(struct northd_input *input_data,
> >               struct northd_data *data,
> > diff --git a/northd/northd.h b/northd/northd.h
> > index d4a8d75ab..37f06ce5d 100644
> > --- a/northd/northd.h
> > +++ b/northd/northd.h
> > @@ -23,6 +23,7 @@
> >  #include "northd/en-port-group.h"
> >  #include "northd/ipam.h"
> >  #include "openvswitch/hmap.h"
> > +#include "simap.h"
> >  #include "ovs-thread.h"
> >
> >  struct northd_input {
> > @@ -160,14 +161,34 @@ struct northd_data {
> >      struct northd_tracked_data trk_data;
> >  };
> >
> > +struct route_policy {
> > +    struct hmap_node key_node;
> > +    const struct nbrec_logical_router_policy *rule;
> > +    size_t n_valid_nexthops;
> > +    char **valid_nexthops;
> > +    const struct nbrec_logical_router *nbr;
> > +    bool stale;
> > +};
> > +
> > +struct static_routes_data {
> > +    struct hmap parsed_routes;
> > +    struct simap route_tables;
> > +    struct hmap bfd_active_connections;
> > +};
> > +
> > +struct route_policies_data {
> > +    struct hmap route_policies;
> > +    struct hmap bfd_active_connections;
> > +};
> > +
> > +struct bfd_data {
> > +    struct hmap bfd_connections;
> > +};
> > +
> >  struct lr_nat_table;
> >
> >  struct lflow_input {
> > -    /* Northbound table references */
> > -    const struct nbrec_bfd_table *nbrec_bfd_table;
> > -
> >      /* Southbound table references */
> > -    const struct sbrec_bfd_table *sbrec_bfd_table;
> >      const struct sbrec_logical_flow_table *sbrec_logical_flow_table;
> >      const struct sbrec_multicast_group_table *sbrec_multicast_group_table;
> >      const struct sbrec_igmp_group_table *sbrec_igmp_group_table;
> > @@ -190,6 +211,9 @@ struct lflow_input {
> >      const struct hmap *svc_monitor_map;
> >      bool ovn_internal_version_changed;
> >      const char *svc_monitor_mac;
> > +    struct hmap *parsed_routes;
> > +    struct hmap *route_policies;
> > +    struct simap *route_tables;
> >  };
> >
> >  extern int parallelization_state;
> > @@ -653,6 +677,20 @@ struct ovn_port {
> >      struct lflow_ref *stateful_lflow_ref;
> >  };
> >
> > +struct parsed_route {
> > +    struct hmap_node key_node;
> > +    struct in6_addr prefix;
> > +    unsigned int plen;
> > +    bool is_src_route;
> > +    uint32_t route_table_id;
> > +    uint32_t hash;
> > +    const struct nbrec_logical_router_static_route *route;
> > +    bool ecmp_symmetric_reply;
> > +    bool is_discard_route;
> > +    const struct nbrec_logical_router *nbr;
> > +    bool stale;
> > +};
> > +
> >  void ovnnb_db_run(struct northd_input *input_data,
> >                    struct northd_data *data,
> >                    struct ovsdb_idl_txn *ovnnb_txn,
> > @@ -674,6 +712,18 @@ void northd_init(struct northd_data *data);
> >  void northd_indices_create(struct northd_data *data,
> >                             struct ovsdb_idl *ovnsb_idl);
> >
> > +void route_policies_init(struct route_policies_data *);
> > +void route_policies_destroy(struct route_policies_data *);
> > +void build_parsed_routes(struct ovn_datapath *, const struct hmap *,
> > +                         struct hmap *, struct hmap *, struct simap *,
> > +                         struct hmap *);
> > +uint32_t get_route_table_id(struct simap *, const char *);
> > +void static_routes_init(struct static_routes_data *);
> > +void static_routes_destroy(struct static_routes_data *);
> > +
> > +void bfd_init(struct bfd_data *);
> > +void bfd_destroy(struct bfd_data *);
> > +
> >  struct lflow_table;
> >  struct lr_stateful_tracked_data;
> >  struct ls_stateful_tracked_data;
> > @@ -711,13 +761,13 @@ bool northd_handle_lb_data_changes(struct tracked_lb_data *,
> >                                     struct hmap *lbgrp_datapaths_map,
> >                                     struct northd_tracked_data *);
> >
> > -void build_bfd_table(struct ovsdb_idl_txn *ovnsb_txn,
> > -                     const struct nbrec_bfd_table *,
> > -                     const struct sbrec_bfd_table *,
> > -                     const struct hmap *lr_ports,
> > -                     struct hmap *bfd_connections);
> > -void bfd_cleanup_connections(const struct nbrec_bfd_table *,
> > -                             struct hmap *bfd_map);
> > +void build_route_policies(struct ovn_datapath *, struct hmap *, struct hmap *,
> > +                          struct hmap *, struct hmap *);
> > +void bfd_table_sync(struct ovsdb_idl_txn *, const struct nbrec_bfd_table *,
> > +                    const struct hmap *, struct hmap *, struct hmap *,
> > +                    struct hmap *);
> > +void build_bfd_map(const struct nbrec_bfd_table *,
> > +                   const struct sbrec_bfd_table *, struct hmap *);
> >  void run_update_worker_pool(int n_threads);
> >
> >  const struct ovn_datapath *northd_get_datapath_for_port(
> > diff --git a/tests/ovn-northd.at b/tests/ovn-northd.at
> > index 199197f09..710500dce 100644
> > --- a/tests/ovn-northd.at
> > +++ b/tests/ovn-northd.at
> > @@ -12,6 +12,7 @@ m4_define([_DUMP_DB_TABLES], [
> >      ovn-sbctl list meter >> $1
> >      ovn-sbctl list meter_band >> $1
> >      ovn-sbctl list port_group >> $1
> > +    ovn-sbctl list bfd >> $1
> >      ovn-sbctl dump-flows > lflows_$1
> >  ])
> >
> > @@ -3861,6 +3862,7 @@ for i in $(seq 1 9); do
> >      check ovn-nbctl --wait=sb lsp-set-addresses sw$i-r0 00:00:00:00:00:0$i
> >  done
> >
> > +check as northd ovn-appctl -t ovn-northd inc-engine/clear-stats
> >  uuid=$(ovn-nbctl create bfd logical_port=r0-sw1 dst_ip=192.168.1.2 status=down min_tx=250 min_rx=250 detect_mult=10)
> >  ovn-nbctl create bfd logical_port=r0-sw2 dst_ip=192.168.2.2 status=down min_tx=500 min_rx=500 detect_mult=20
> >  ovn-nbctl create bfd logical_port=r0-sw3 dst_ip=192.168.3.2 status=down
> > @@ -3873,6 +3875,13 @@ wait_row_count bfd 1 logical_port=r0-sw2 detect_mult=20 dst_ip=192.168.2.2 \
> >  wait_row_count bfd 1 logical_port=r0-sw3 detect_mult=5 dst_ip=192.168.3.2 \
> >                       min_rx=1000 min_tx=1000 status=admin_down
> >
> > +check_engine_stats northd norecompute nocompute
> > +check_engine_stats bfd recompute nocompute
> > +check_engine_stats lflow recompute nocompute
> > +check_engine_stats northd_output norecompute compute
> > +CHECK_NO_CHANGE_AFTER_RECOMPUTE
> > +check as northd ovn-appctl -t ovn-northd inc-engine/clear-stats
> > +
> >  uuid=$(fetch_column nb:bfd _uuid logical_port=r0-sw1)
> >  check ovn-nbctl set bfd $uuid min_tx=1000 min_rx=1000 detect_mult=100
> >
> > @@ -3881,10 +3890,25 @@ check ovn-nbctl clear bfd $uuid_2 min_rx
> >  wait_row_count bfd 1 logical_port=r0-sw2 min_rx=1000
> >  wait_row_count bfd 1 logical_port=r0-sw1 min_rx=1000 min_tx=1000 detect_mult=100
> >
> > +check_engine_stats northd norecompute nocompute
> > +check_engine_stats bfd recompute nocompute
> > +check_engine_stats lflow recompute nocompute
> > +check_engine_stats northd_output norecompute compute
> > +CHECK_NO_CHANGE_AFTER_RECOMPUTE
> > +check as northd ovn-appctl -t ovn-northd inc-engine/clear-stats
> > +
> >  check ovn-nbctl --bfd=$uuid lr-route-add r0 100.0.0.0/8 192.168.1.2
> >  wait_column down bfd status logical_port=r0-sw1
> >  AT_CHECK([ovn-nbctl lr-route-list r0 | grep 192.168.1.2 | grep -q bfd],[0])
> >
> > +check_engine_stats northd recompute nocompute
> > +check_engine_stats bfd recompute nocompute
> > +check_engine_stats static_routes recompute nocompute
> > +check_engine_stats lflow recompute nocompute
> > +check_engine_stats northd_output norecompute compute
> > +CHECK_NO_CHANGE_AFTER_RECOMPUTE
> > +check as northd ovn-appctl -t ovn-northd inc-engine/clear-stats
> > +
> >  check ovn-nbctl --bfd lr-route-add r0 200.0.0.0/8 192.168.2.2
> >  wait_column down bfd status logical_port=r0-sw2
> >  AT_CHECK([ovn-nbctl lr-route-list r0 | grep 192.168.2.2 | grep -q bfd],[0])
> > @@ -3893,10 +3917,26 @@ check ovn-nbctl --bfd lr-route-add r0 240.0.0.0/8 192.168.5.2 r0-sw5
> >  wait_column down bfd status logical_port=r0-sw5
> >  AT_CHECK([ovn-nbctl lr-route-list r0 | grep 192.168.5.2 | grep -q bfd],[0])
> >
> > +check_engine_stats northd recompute nocompute
> > +check_engine_stats bfd recompute nocompute
> > +check_engine_stats static_routes recompute nocompute
> > +check_engine_stats lflow recompute nocompute
> > +check_engine_stats northd_output norecompute compute
> > +CHECK_NO_CHANGE_AFTER_RECOMPUTE
> > +check as northd ovn-appctl -t ovn-northd inc-engine/clear-stats
> > +
> >  check ovn-nbctl --bfd --policy=src-ip lr-route-add r0 192.168.6.1/32 192.168.10.10 r0-sw6
> >  wait_column down bfd status logical_port=r0-sw6
> >  AT_CHECK([ovn-nbctl lr-route-list r0 | grep 192.168.6.1 | grep -q bfd],[0])
> >
> > +check_engine_stats northd recompute nocompute
> > +check_engine_stats bfd recompute nocompute
> > +check_engine_stats route_policies recompute nocompute
> > +check_engine_stats lflow recompute nocompute
> > +check_engine_stats northd_output norecompute compute
> > +CHECK_NO_CHANGE_AFTER_RECOMPUTE
> > +check as northd ovn-appctl -t ovn-northd inc-engine/clear-stats
> > +
> >  check ovn-nbctl --bfd --policy=src-ip lr-route-add r0 192.168.7.1/32 192.168.10.10 r0-sw7
> >  wait_column down bfd status logical_port=r0-sw7
> >  AT_CHECK([ovn-nbctl lr-route-list r0 | grep 192.168.7.1 | grep -q bfd],[0])
> > @@ -3924,6 +3964,14 @@ wait_column down bfd status logical_port=r0-sw8
> >  bfd_route_policy_uuid=$(fetch_column nb:bfd _uuid logical_port=r0-sw8)
> >  AT_CHECK([ovn-nbctl list logical_router_policy | grep -q $bfd_route_policy_uuid])
> >
> > +check_engine_stats northd recompute nocompute
> > +check_engine_stats bfd recompute nocompute
> > +check_engine_stats static_routes recompute nocompute
> > +check_engine_stats lflow recompute nocompute
> > +check_engine_stats northd_output norecompute compute
> > +CHECK_NO_CHANGE_AFTER_RECOMPUTE
> > +check as northd ovn-appctl -t ovn-northd inc-engine/clear-stats
> > +
> >  check ovn-nbctl lr-policy-del r0
> >  check ovn-nbctl --bfd lr-policy-add r0 100 "ip4.src == 2.3.4.0/24" reroute 192.168.9.2,192.168.9.3,192.168.9.4
> >
> > @@ -3931,6 +3979,14 @@ wait_column down bfd status dst_ip=192.168.9.2
> >  wait_column down bfd status dst_ip=192.168.9.3
> >  wait_column down bfd status dst_ip=192.168.9.4
> >
> > +check_engine_stats northd recompute nocompute
> > +check_engine_stats bfd recompute nocompute
> > +check_engine_stats route_policies recompute nocompute
> > +check_engine_stats lflow recompute nocompute
> > +check_engine_stats northd_output norecompute compute
> > +CHECK_NO_CHANGE_AFTER_RECOMPUTE
> > +check as northd ovn-appctl -t ovn-northd inc-engine/clear-stats
> > +
> >  bfd_route_policy_uuid=$(fetch_column nb:bfd _uuid logical_port=r0-sw9)
> >  AT_CHECK([ovn-nbctl list logical_router_policy | sed s/,//g | grep -q "$bfd_route_policy_uuid"])
> >
> > --
> > 2.45.2
> >
>