[PATCH net-next 1/8] rtnetlink: Do not generate notifications for MTU events

[David Ahern]

Changing MTU on a link currently causes 3 messages to be sent to userspace:

[LINK]11: dummy1: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1490 qdisc noqueue state 
UNKNOWN group default event PRE_CHANGE_MTU
    link/ether f2:52:5c:6d:21:f3 brd ff:ff:ff:ff:ff:ff

[LINK]11: dummy1: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state 
UNKNOWN group default event CHANGE_MTU
    link/ether f2:52:5c:6d:21:f3 brd ff:ff:ff:ff:ff:ff

[LINK]11: dummy1: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state 
UNKNOWN group default
    link/ether f2:52:5c:6d:21:f3 brd ff:ff:ff:ff:ff:ff

Remove the PRE_CHANGE_MTU and CHANGE_MTU messages.

Signed-off-by: David Ahern <d...@cumulusnetworks.com>
---
 include/uapi/linux/if_link.h | 2 --
 net/core/rtnetlink.c         | 8 --------
 2 files changed, 10 deletions(-)

diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 97f6d302f627..e8b7e9342cc0 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -903,7 +903,6 @@ enum {
 enum {
        IFLA_EVENT_UNSPEC,
        IFLA_EVENT_REBOOT,
-       IFLA_EVENT_CHANGE_MTU,
        IFLA_EVENT_CHANGE_ADDR,
        IFLA_EVENT_CHANGE_NAME,
        IFLA_EVENT_FEAT_CHANGE,
@@ -912,7 +911,6 @@ enum {
        IFLA_EVENT_NOTIFY_PEERS,
        IFLA_EVENT_CHANGE_UPPER,
        IFLA_EVENT_RESEND_IGMP,
-       IFLA_EVENT_PRE_CHANGE_MTU,
        IFLA_EVENT_CHANGE_INFO_DATA,
        IFLA_EVENT_PRE_CHANGE_UPPER,
        IFLA_EVENT_CHANGE_LOWER_STATE,
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index b2bd4c9ee860..72d365ae14b3 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1285,9 +1285,6 @@ static int rtnl_fill_link_event(struct sk_buff *skb, 
unsigned long event)
        case NETDEV_REBOOT:
                rtnl_event = IFLA_EVENT_REBOOT;
                break;
-       case NETDEV_CHANGEMTU:
-               rtnl_event = IFLA_EVENT_CHANGE_MTU;
-               break;
        case NETDEV_CHANGEADDR:
                rtnl_event = IFLA_EVENT_CHANGE_ADDR;
                break;
@@ -1312,9 +1309,6 @@ static int rtnl_fill_link_event(struct sk_buff *skb, 
unsigned long event)
        case NETDEV_RESEND_IGMP:
                rtnl_event = IFLA_EVENT_RESEND_IGMP;
                break;
-       case NETDEV_PRECHANGEMTU:
-               rtnl_event = IFLA_EVENT_PRE_CHANGE_MTU;
-               break;
        case NETDEV_CHANGEINFODATA:
                rtnl_event = IFLA_EVENT_CHANGE_INFO_DATA;
                break;
@@ -4191,7 +4185,6 @@ static int rtnetlink_event(struct notifier_block *this, 
unsigned long event, voi
 
        switch (event) {
        case NETDEV_REBOOT:
-       case NETDEV_CHANGEMTU:
        case NETDEV_CHANGEADDR:
        case NETDEV_CHANGENAME:
        case NETDEV_FEAT_CHANGE:
@@ -4200,7 +4193,6 @@ static int rtnetlink_event(struct notifier_block *this, 
unsigned long event, voi
        case NETDEV_NOTIFY_PEERS:
        case NETDEV_CHANGEUPPER:
        case NETDEV_RESEND_IGMP:
-       case NETDEV_PRECHANGEMTU:
        case NETDEV_CHANGEINFODATA:
        case NETDEV_PRECHANGEUPPER:
        case NETDEV_CHANGELOWERSTATE:
-- 
2.1.4