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Date: Fri, 24 Jul 2015 09:50:10 -0700
Message-ID: <CAJ-VmokvtH4ZP8bw_MSXAfxf-=g8ANLoKS3=-VjMhALufsRDtA@mail.gmail.com>
Subject: Re: struct timehands: th_generation field
From: Adrian Chadd <adrian.chadd@gmail.com>
To: deco33000@yandex.com
Cc: freebsd-stable <freebsd-stable@freebsd.org>
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accessing hardware isn't free. Locking also isn't free. That's why
there's this mechanism.



-adrian


On 24 July 2015 at 08:58,  <deco33000@yandex.com> wrote:
>
> OK.
>
> I read the document and understood it I guess.
> Very interesting, and well engineered.
>
> On x86/i386/amd64, could not all this be replaced by a simple call to apic timer ?
> We would get the timestamp, we can even store it, make calculation on top of it.
>
> My jugement may miss something important though. That is why I ask :)
>
>
> --
> Jog
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