From mboxrd@z Thu Jan  1 00:00:00 1970
From: Florian Westphal <fw@strlen.de>
Subject: Re: [PATCH] tcp: syncookies: do not use getnstimeofday()
Date: Wed, 19 Mar 2014 23:56:42 +0100
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Cc: Florian Westphal <fw@strlen.de>, netdev@vger.kernel.org
To: Eric Dumazet <eric.dumazet@gmail.com>
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Eric Dumazet <eric.dumazet@gmail.com> wrote:
> While it is true that getnstimeofday() uses about 40 cycles if TSC
> is available, it can use 1600 cycles if hpet is the clocksource.

Ouch.  Why is secure_tcp_sequence_number also using
ktime_get_real/getnstimeofday?

clock drift when other cpu is used?

[ Just curious; I have no objections to this patch ]