From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] ipv6: Enable RFS sk_rxhash tracking for ipv6 sockets
Date: Wed, 06 Apr 2011 11:27:12 -0700 (PDT)
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=46rom: Eric Dumazet <eric.dumazet@gmail.com>
Date: Wed, 06 Apr 2011 20:23:08 +0200

> Le mercredi 06 avril 2011 =E0 11:17 -0700, David Miller a =E9crit :
>> From: Eric Dumazet <eric.dumazet@gmail.com>
>> Date: Wed, 06 Apr 2011 20:07:33 +0200
>>=20
>> > This is why we used on ipv4 :
>> >=20
>> > if (inet_sk(sk)->inet_daddr)
>> > 	sock_rps_save_rxhash(sk, skb->rxhash);
>> >=20
>> >=20
>> > Only arm RFS on UDP if socket is bound to a given remote peer.
>>=20
>> Agreed, Neil please make this change to your ipv6 code.
>=20
> BTW, do you guys know if NFS is using RFS right now (if TCP transport=
 is
> used) ?

It ought to be.  Are you specifically concerned that it might be
missing the rxhash setting calls because of the APIs it uses to
do socket I/O?

The SunRPC layer is a major user of tcp_read_sock(), for example.

But the packet processing will be done via the normal means,
therefore we'll hit tcp_v4_do_rcv() and therefore save the
rxhash.