From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas.monjalon-pdR9zngts4EAvxtiuMwx3w@public.gmane.org>
Subject: Re: [PATCH] timer: add lfence before TSC read
Date: Mon, 27 Jan 2014 10:57:52 +0100
Message-ID: <201401271057.52251.thomas.monjalon@6wind.com>
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To: "=?iso-8859-1?q?Fran=E7ois-Fr=E9d=E9ric?= Ozog" <ff-SpBG2i6TTxU@public.gmane.org>,
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24/01/2014 12:42, Fran=E7ois-Fr=E9d=E9ric Ozog:
> IMHO, adding the lfence for all cases is introducing an un-necessary
> performance penalty.
>=20
> What about adding rte_rdtsc_sync() or rte_rdtsc_serial() with the comment
> about the rdtsc instruction behavior so that developers can choose which
> form they want?

Yes it could be a good idea in some cases. Didier, could you try to add suc=
h=20
function ?

But in some debugging cases we need to have high precision for almost all=20
timestamps. Here I don't know what is the smartest solution.

Thank you for commenting. Hope we'll find a good fix.
=2D-=20
Thomas