From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <stephen@networkplumber.org>
Subject: Re: [PATCH] eal: roundup tsc frequency when estimating it
Date: Thu, 29 Nov 2018 13:21:52 -0800
Message-ID: <20181129132152.754ce410@xeon-e3>
References: <20181129083138.23029-1-pbhagavatula@caviumnetworks.com>
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Cc: "Jacob,  Jerin" <Jerin.JacobKollanukkaran@cavium.com>, "dev@dpdk.org"
 <dev@dpdk.org>, "Bhagavatula, Pavan" <Pavan.Bhagavatula@cavium.com>
To: Pavan Nikhilesh <pbhagavatula@caviumnetworks.com>
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On Thu, 29 Nov 2018 08:32:03 +0000
Pavan Nikhilesh <pbhagavatula@caviumnetworks.com> wrote:

> When estimating tsc frequency using sleep/gettime round it up to the
> nearest multiple of 10Mhz for more accuracy.
> 
> Signed-off-by: Pavan Nikhilesh <pbhagavatula@caviumnetworks.com>

Rounding reduces accuracy.

Why is this code being used?  Shouldn't get_tsc_freq_arch return a
correct value?

How well does the rdmsr() logic work in VM?
It looks like Hyper-V has special MSR's for TSC frequency determination.