[Bridge] [PATCHv3] bridge: disable snooping if there is no querier

[David Miller]

From: Linus Lüssing <linus.luessing at web.de>
Date: Thu,  1 Aug 2013 01:06:20 +0200

> If there is no querier on a link then we won't get periodic reports and
> therefore won't be able to learn about multicast listeners behind ports,
> potentially leading to lost multicast packets, especially for multicast
> listeners that joined before the creation of the bridge.
> 
> These lost multicast packets can appear since c5c23260594
> ("bridge: Add multicast_querier toggle and disable queries by default")
> in particular.
> 
> With this patch we are flooding multicast packets if our querier is
> disabled and if we didn't detect any other querier.
> 
> A grace period of the Maximum Response Delay of the querier is added to
> give multicast responses enough time to arrive and to be learned from
> before disabling the flooding behaviour again.
> 
> Signed-off-by: Linus Lüssing <linus.luessing at web.de>

Looks good, applied, thanks Linus.