On Tue,  4 Dec 2012 17:56:40 +0800
Cong Wang [off-list ref] wrote:

V2: make the toggle per-port

Fast leave allows bridge to immediately stops the multicast
traffic on the port receives IGMP Leave when IGMP snooping is enabled,
no timeouts are observed.

Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Stephen Hemminger <redacted>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <redacted>

Ok. as is.

A good followup change would be to migrate
these multicast flags into the existing flags bits (see hairpin etc),
and make them manageable via netlink.