Re: git: x86_64 mptable - maximum lapic id is 64

[Alex Hornung <ahornung@xxxxxxxxx>]

On 30 Jul 2012, at 02:46, Sepherosa Ziehau <sepherosa@gmail.com> wrote:

> On Sun, Jul 29, 2012 at 10:59 PM, Alex Hornung
> <alexh@crater.dragonflybsd.org> wrote:
>> 
>> commit c81c1e3460b022d0083fcd243e745318f5c04a17
>> Author: Alex Hornung <alex@alexhornung.com>
>> Date:   Sun Jul 29 12:00:53 2012 +0000
>> 
>>    x86_64 mptable - maximum lapic id is 64
>> 
>>     * In x86_64, lapic ids with HT can be up to 64, not 32 as in i386.
> 
> Hmm, are you using MPTABLE to detect CPU topology?  I suggest avoid
> using MPTABLE, if possible.  

These commits are all about ncpus being wrong on ftigeot's dual xeon machine. The issue resulted in DragonFly not using all the cores/threads, just half of them. It has nothing to do directly with the cpu topology code, which does not use mptable.

Cheers,
Alex