From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH 6/7] mlx4_en: Adding rxhash support
Date: Tue, 18 Oct 2011 03:48:45 +0200
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Cc: davem@davemloft.net, netdev@vger.kernel.org
To: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
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Le lundi 17 octobre 2011 =C3=A0 22:18 +0200, Yevgeny Petrilin a =C3=A9c=
rit :
> Moving to Toeplitz function in RSS calculation.
> Reporting rxhash in skb.
>=20
> Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>

>  	rss_context->flags =3D rss_mask;
> +	rss_context->hash_fn =3D 1;
> +	for (i =3D 0; i < 10; i++)
> +		rss_context->rss_key[i] =3D random32();
> =20

Thats bit of a problem : Two NICS will have different seeds, and thus
provide different rxhash for a given flow. A bonding of two NICS will
not be able to provide a consistent rxhash.

drivers/net/ethernet/intel/igb/igb_main.c uses a static table to avoid
this problem.