From: Eric Dumazet <eric.dumazet@gmail.com>
To: Anatoly Sivov <mm05@mail.ru>
Cc: netdev@vger.kernel.org
Subject: Re: why does skb->tstamp use getnstimeofday?
Date: Sun, 15 Jan 2012 17:42:30 +0100 [thread overview]
Message-ID: <1326645750.5287.48.camel@edumazet-laptop> (raw)
In-Reply-To: <op.v74shh18fzo5me@stalin>
Le dimanche 15 janvier 2012 à 19:11 +0400, Anatoly Sivov a écrit :
> Hello everyone.
>
> struct sk_buff has a field tstamp, which is used for high resolution rtt
> calculation.
> All operations with this field are done directly or indirectly via ktime_*
> interface,
> which uses getnstimeofday function.
> My question is why does skb->tstamp use getnstimeofday?
> Isn't it better to use getrawmonotonic, where we are not inetrfered with
> ntp, for rtt calculation?
>
It's using this since day 0, so cannot be changed or break applications,
which expect timeofday, not monotonic.
monotonic time services were added later.
next prev parent reply other threads:[~2012-01-15 16:42 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-15 15:11 why does skb->tstamp use getnstimeofday? Anatoly Sivov
2012-01-15 16:42 ` Eric Dumazet [this message]
2012-01-15 17:55 ` Anatoly Sivov
2012-01-15 18:00 ` Anatoly Sivov
2012-01-15 18:56 ` Eric Dumazet
2012-01-15 19:55 ` Anatoly Sivov
2012-01-16 22:05 ` Rick Jones
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