From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH 2/2] packet: Add fanout support.
Date: Tue, 05 Jul 2011 08:21:15 +0200
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References: <20110704.212014.236340473910292460.davem@davemloft.net>
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To: David Miller <davem@davemloft.net>
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Le lundi 04 juillet 2011 =C3=A0 21:20 -0700, David Miller a =C3=A9crit =
:
> Fanouts allow packet capturing to be demuxed to a set of AF_PACKET
> sockets.  Two fanout policies are implemented:
>=20
> 1) Hashing based upon skb->rxhash

=2E..

> +
> +static struct sock *fanout_demux_hash(struct packet_fanout *f, struc=
t sk_buff *skb)
> +{
> +	u32 idx, hash =3D skb->rxhash;
> +
> +	idx =3D ((u64)hash * f->num_members) >> 32;
> +
> +	return f->arr[idx];
> +}
> +

rxhash is 0 unless skb_get_rxhash() was called, or some NIC set it in R=
X
path.