From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Tue, 30 Aug 2011 23:31:58 +0000 (+0000)
Subject: net: linkwatch: allow vlans to get carrier changes faster
X-Git-Tag: v3.2-rc1~129^2~315
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c37e0c993055d8c4fd82202331d06e6ef9bfec4b;p=pandora-kernel.git

net: linkwatch: allow vlans to get carrier changes faster

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>
---

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