Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 07 Mar 2002 18:11:31 -0500 (EST)
From:      John Baldwin <jhb@FreeBSD.org>
To:        Matthew Jacob <mjacob@feral.com>
Cc:        cvs-committers@FreeBSD.org, cvs-all@FreeBSD.org, Jeff Roberson <jeff@FreeBSD.org>
Subject:   RE: cvs commit: src/sys/sys smp.h src/sys/kern subr_smp.c src/sy
Message-ID:  <XFMail.020307181131.jhb@FreeBSD.org>
In-Reply-To: <Pine.BSF.4.21.0203071421000.42005-100000@beppo>

next in thread | previous in thread | raw e-mail | index | archive | help

On 07-Mar-02 Matthew Jacob wrote:
>> 
>> Yes, well, the current Alpha ID's do fit this model. :)  I think you want
>> what we already have.  If we do end up with an arch which uses 64-bit
>> phyiscal ID numbers or other such weirdness then it is free to assign
>> logical ID's as it sees fit.  We just happen to use the phyiscal ID for
>> the virtaul ID on Alpha, i386 (and sparc64 I believe) since they do fit
>> these requirements.
>> 
>> Does that make sense?  I'm not say we need to support some wildly sparse
>> range, but we shouldn't assume 0 and 1 for any dual CPU system.
> 
> The latter certainly. I would like everyone to assume a sparse space. After
> all, under the current implementation, the first CPU for an Alpha 8200 is at
> ID 8, not 0.
> 
> As far as the rest- fair enough, I suppose. But as long as you just keep the
> notion that these are phyical IDs, then people will make (IMO) unwarranted
> assumptions about this over time, and as soon as you *get* a platform that
> doesn't fit this, you're in trouble. 

Ah, I see where you are gettnig at I think.  Yes, the logical ID's should be
treated as virtual ID's by consumers and no correlation to physical ID's should
be assumed.  It is just an implementation detail of the current Alpha CPU ID
mapping and I was merely using it as an example of where a sparse mapping can
appear. :)

> -matt

-- 

John Baldwin <jhb@FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve!"  -  http://www.FreeBSD.org/

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe cvs-all" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?XFMail.020307181131.jhb>