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Date:   Thu, 12 Dec 2019 18:31:14 +0100
From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     Daniel Wagner <wagi@monom.org>
Cc:     Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= <ukleinek@debian.org>,
        Clark Williams <williams@redhat.com>,
        John Kacur <jkacur@redhat.com>, linux-rt-users@vger.kernel.org
Subject: Re: [PATCH rt-tests] queuelat: use ARM implementation of gettick
 also for all !x86 archs
Message-ID: <20191212173114.cz3bq5eotczql5s2@linutronix.de>
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 <18a0be03-74dd-54f1-a0f0-4f4acdd061ad@monom.org>
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On 2019-12-09 10:40:29 [+0100], Daniel Wagner wrote:
> Just wondering if the tool should print a warning if the fallback is used?
> IIRC, the code wants to use the TSC and clock_gettime is probably not so
> precise.

clock_gettime() is precise but it might have more overhead. With VDSO
support the overhead is quite low.

> Thanks,
> Daniel

Sebastian