[RFC PATCH net-next 15/22] nexthop: Emit a notification when a nexthop group is reduced

[Ido Schimmel]

From: Ido Schimmel <ido...@nvidia.com>

When a single nexthop is deleted, the configuration of all the groups
using the nexthop is effectively modified. In this case, emit a
notification in the nexthop notification chain for each modified group
so that listeners would not need to keep track of which nexthops are
member in which groups.

In the rare cases where the notification fails, emit an error to the
kernel log.

Signed-off-by: Ido Schimmel <ido...@nvidia.com>
---
 net/ipv4/nexthop.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/net/ipv4/nexthop.c b/net/ipv4/nexthop.c
index 0edc3e73d416..33f611bbce1f 100644
--- a/net/ipv4/nexthop.c
+++ b/net/ipv4/nexthop.c
@@ -893,7 +893,7 @@ static void remove_nh_grp_entry(struct net *net, struct 
nh_grp_entry *nhge,
        struct nexthop *nhp = nhge->nh_parent;
        struct nexthop *nh = nhge->nh;
        struct nh_group *nhg, *newg;
-       int i, j;
+       int i, j, err;
 
        WARN_ON(!nh);
 
@@ -941,6 +941,10 @@ static void remove_nh_grp_entry(struct net *net, struct 
nh_grp_entry *nhge,
        list_del(&nhge->nh_list);
        nexthop_put(nhge->nh);
 
+       err = call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, nhp, NULL);
+       if (err)
+               pr_err("Failed to replace nexthop group after nexthop 
deletion\n");
+
        if (nlinfo)
                nexthop_notify(RTM_NEWNEXTHOP, nhp, nlinfo);
 }
-- 
2.26.2