From c37e0c993055d8c4fd82202331d06e6ef9bfec4b Mon Sep 17 00:00:00 2001 From: Eric Dumazet <eric.dumazet@gmail.com> Date: Tue, 30 Aug 2011 23:31:58 +0000 Subject: [PATCH] net: linkwatch: allow vlans to get carrier changes faster MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit There is a time-lag of IFF_RUNNING flag consistency between vlan and real devices when the real devices are in problem such as link or cable broken. This leads to a degradation of Availability such as a delay of failover in HA systems using vlan since the detection of the problem at real device is delayed. We can avoid the linkwatch delay (~1 sec) for devices linked to another ones, since delay is already done for the realdev. Based on a previous patch from Mitsuo Hayasaka Reported-by: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Patrick McHardy <kaber@trash.net> Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl> Cc: Tom Herbert <therbert@google.com> Cc: Stephen Hemminger <shemminger@vyatta.com> Cc: Jesse Gross <jesse@nicira.com> Tested-by: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com> Signed-off-by: David S. Miller <davem@davemloft.net> --- net/core/link_watch.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/net/core/link_watch.c b/net/core/link_watch.c index 357bd4ee4baa..c3519c6d1b16 100644 --- a/net/core/link_watch.c +++ b/net/core/link_watch.c @@ -78,8 +78,13 @@ static void rfc2863_policy(struct net_device *dev) static bool linkwatch_urgent_event(struct net_device *dev) { - return netif_running(dev) && netif_carrier_ok(dev) && - qdisc_tx_changing(dev); + if (!netif_running(dev)) + return false; + + if (dev->ifindex != dev->iflink) + return true; + + return netif_carrier_ok(dev) && qdisc_tx_changing(dev); }