[ovs-dev] [PATCH 1/3] netdev-linux: Make netdev_linux_notify_sock join RTNLGRP_IPV4_IFADDR and RTNLGRP_IPV6_IFADDR.

[Alex Wang]

Currently the netdev_linux_notify_sock only joins multicast group
RTNLGRP_LINK for link status change notification.  Some ovs features
also require the detection of ip addresses changes and update of the
netdev-linux's cache.  To achieve this, we need to make
netdev_linux_notify_sock join the multicast group RTNLGRP_IPV4_IFADDR
and RTNLGRP_IPV6_IFADDR.

Signed-off-by: Alex Wang <alexw at nicira.com>
---
 lib/netdev-linux.c |   15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/lib/netdev-linux.c b/lib/netdev-linux.c
index 0656f36..fa27312 100644
--- a/lib/netdev-linux.c
+++ b/lib/netdev-linux.c
@@ -554,16 +554,23 @@ netdev_linux_notify_sock(void)
 {
     static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
     static struct nl_sock *sock;
+    unsigned int mcgroups[3] = {RTNLGRP_LINK, RTNLGRP_IPV4_IFADDR,
+                                RTNLGRP_IPV6_IFADDR};
 
     if (ovsthread_once_start(&once)) {
         int error;
 
         error = nl_sock_create(NETLINK_ROUTE, &sock);
         if (!error) {
-            error = nl_sock_join_mcgroup(sock, RTNLGRP_LINK);
-            if (error) {
-                nl_sock_destroy(sock);
-                sock = NULL;
+            size_t i;
+
+            for (i = 0; i < ARRAY_SIZE(mcgroups); i++) {
+                error = nl_sock_join_mcgroup(sock, mcgroups[i]);
+                if (error) {
+                    nl_sock_destroy(sock);
+                    sock = NULL;
+                    break;
+                }
             }
         }
         ovsthread_once_done(&once);
-- 
1.7.9.5