From: Eric Dumazet <eric.dumazet@gmail.com>
To: Tom Herbert <therbert@google.com>
Cc: davem@davemloft.net, netdev@vger.kernel.org
Subject: Re: [PATCH 1/2 v2] net: Add function to get SW rxhash
Date: Tue, 24 Sep 2013 14:30:03 -0700 [thread overview]
Message-ID: <1380058203.3165.121.camel@edumazet-glaptop> (raw)
In-Reply-To: <alpine.DEB.2.02.1309241335380.23856@tomh.mtv.corp.google.com>
On Tue, 2013-09-24 at 13:42 -0700, Tom Herbert wrote:
> Some uses of skb_get_rxhash expect that the function will return
> a consistent value whether it is called on RX or TX paths. On RX
> path, we will use the rxhash if provided by the NIC, so this
> would not normally be the same result computed in TX path would be
> a software calculation.
>
> This patch adds skb_get_sw_rxhash to explicitly request a hash
> calculated by the stack, disregarding the hash provided by NIC.
As I said, I think this is overhead in network fast path.
This can be done without adding a new skb field.
I suspect tun should not use rxhash but a proper hash, as conntrack or
tcp...
next prev parent reply other threads:[~2013-09-24 21:30 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-24 20:42 [PATCH 1/2 v2] net: Add function to get SW rxhash Tom Herbert
2013-09-24 21:30 ` Eric Dumazet [this message]
2013-09-24 22:16 ` Tom Herbert
2013-09-25 0:17 ` Eric Dumazet
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