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Message-ID: <55686C0F.9000101@embedded-brains.de>
Date: Fri, 29 May 2015 15:39:27 +0200
From: Sebastian Huber <sebastian.huber@embedded-brains.de>
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To: Poul-Henning Kamp <phk@phk.freebsd.dk>
CC: freebsd-hackers@freebsd.org
Subject: Re: Problem with timecounters and memory model
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On 29/05/15 15:36, Poul-Henning Kamp wrote:
> --------
> In message <55686300.3080100@embedded-brains.de>, Sebastian Huber write=
s:
>
>> This version seems to work at least on uni-processor systems. Shouldn'=
t
>> there be real memory barriers the synchronize the reads/writes to
>> th_generation for SMP machines?
> yes, there should.
>
> (I must admit that I havn't looked at that code for about five or ten y=
ears.)
>

Ok, what makes me wonder is why this problem didn't show up in FreeBSD.=20
In our case we observed backward jumps in the supposed to be monotonic=20
uptime.

--=20
Sebastian Huber, embedded brains GmbH

Address : Dornierstr. 4, D-82178 Puchheim, Germany
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Fax     : +49 89 189 47 41-09
E-Mail  : sebastian.huber@embedded-brains.de
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Diese Nachricht ist keine gesch=E4ftliche Mitteilung im Sinne des EHUG.