From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH v5] rps: Receive Packet Steering
Date: Thu, 21 Jan 2010 10:16:21 +0100
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Cc: Tom Herbert <therbert@google.com>, davem@davemloft.net,
	netdev@vger.kernel.org
To: Changli Gao <xiaosuo@gmail.com>
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Le 21/01/2010 08:54, Changli Gao a =C3=A9crit :
> Sometimes, rxhash will be 0 generated. In order to check whether
> rxhash is generated or not, a new bit field in sk_buff is needed. Whe=
n
> rxhash is generated and saved in sk_buff, the bit is set.
>=20
> And, I think rxhash should be reserved when calling skb_copy and skb_=
clone.
>=20
>=20

I disagree

A null rxhash should not be generated by a driver, or even if its null,
why should we care ?

In this very unlikely event, let get_rps_cpu() compute a (non null) has=
h.

Adding a bit in skb for such low probability event brings nothing but c=
omplexity.