Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 30 May 1996 23:37:29 +0000
From:      Poul-Henning Kamp <phk@critter.tfs.com>
To:        erich@uruk.org
Cc:        freebsd-smp@freebsd.org
Subject:   Re: How do you get the SMP code 
Message-ID:  <5515.833499449@critter.tfs.com>
In-Reply-To: Your message of "Thu, 30 May 1996 16:27:24 MST." <199605302327.QAA08265@uruk.org> 

next in thread | previous in thread | raw e-mail | index | archive | help
> If you're going to use it a lot, load the APIC id once in a routine (or
> for that matter, index a "logical CPU number" and keep it around instead).

But where would I keep it my dear man ?   :-)

I will always have to start out at the APIC_ID...
We don't have any "per-cpu" VM (this is different from "terrys" code).

> On both Pentium and Pentium Pro, you have the time-stamp counter.  The
> only problem with this is during periods when your clock input is slowed
> down or halted, such as for power-down...  but any other clock would
> probably suffer the same fate.
check out the IBM POWER design.  The other problem with the cycle counter
is that it will cost you much time to convert from some random resolution
(6.666 ns) to a standard on (1 ns).

--
Poul-Henning Kamp           | phk@FreeBSD.ORG       FreeBSD Core-team.
http://www.freebsd.org/~phk | phk@login.dknet.dk    Private mailbox.
whois: [PHK]                | phk@ref.tfs.com       TRW Financial Systems, Inc.
Future will arrive by its own means, progress not so.



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?5515.833499449>