From: Florian Westphal <fw@strlen.de>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Florian Westphal <fw@strlen.de>, netdev@vger.kernel.org
Subject: Re: [PATCH] tcp: syncookies: do not use getnstimeofday()
Date: Wed, 19 Mar 2014 23:56:42 +0100 [thread overview]
Message-ID: <20140319225642.GA5080@breakpoint.cc> (raw)
In-Reply-To: <1395263181.9114.69.camel@edumazet-glaptop2.roam.corp.google.com>
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 ]
next prev parent reply other threads:[~2014-03-19 22:56 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-20 20:32 [PATCH v3 -next 1/2] tcp: syncookies: reduce cookie lifetime to 128 seconds Florian Westphal
2013-09-20 20:32 ` [PATCH v3 -next 2/2] tcp: syncookies: reduce mss table to four values Florian Westphal
2013-09-24 14:40 ` David Miller
2013-09-24 14:40 ` [PATCH v3 -next 1/2] tcp: syncookies: reduce cookie lifetime to 128 seconds David Miller
2014-03-19 20:38 ` Eric Dumazet
2014-03-19 21:06 ` [PATCH] tcp: syncookies: do not use getnstimeofday() Eric Dumazet
2014-03-19 22:56 ` Florian Westphal [this message]
2014-03-20 2:26 ` Eric Dumazet
2014-03-20 2:37 ` Eric Dumazet
2014-03-20 4:02 ` [PATCH v2] " Eric Dumazet
2014-03-20 8:45 ` Florian Westphal
2014-03-20 19:36 ` David Miller
2014-03-20 20:07 ` Eric Dumazet
2014-03-20 20:16 ` David Miller
2014-03-20 20:37 ` Eric Dumazet
2014-03-20 20:23 ` David Miller
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