Herbert Xu says:
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macvlan: Avoid unnecessary multicast cloning
This patch tries to improve macvlan multicast performance by
maintaining a filter hash at the macvlan_port level so that we
can quickly determine whether a given packet is needed or not.
It is preceded by a patch that fixes a potential use-after-free
bug that I discovered while looking over this.
v2 fixed a bug where promiscuous/allmulti settings weren't handled
correctly.
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Signed-off-by: David S. Miller <davem@davemloft.net>