Re: Purpose of numa_node?

From: Yinghai Lu
Date: Thu Jan 31 2008 - 18:35:31 EST


On Jan 31, 2008 1:42 PM, Yinghai Lu <yhlu.kernel@xxxxxxxxx> wrote:
>
> On Jan 31, 2008 1:35 PM, Brice Goglin <Brice.Goglin@xxxxxxxx> wrote:
> > Yinghai Lu wrote:
> > > On Jan 31, 2008 5:42 AM, Brice Goglin <Brice.Goglin@xxxxxxxx> wrote:
> > >
> > >> It works fine on regular machines such as dual opterons. However, I
> > >> noticed recently that it was wrong on some quad-opteron machines (see
> > >> http://marc.info/?l=linux-pci&m=119072400008538&w=2) because something
> > >> is not initialized in the right order. But I haven't tested 2.6.24 on
> > >> this hardware yet, and I don't know if things have changed regarding this.
> > >>
> > >
> > > that will depend if you dsdt have _PXM for your pci root bus.
> > > otherwise you will get all -1
> > >
> >
> > Have a look at the above link. I don't get -1. I get 0 everywhere, while
> > I should get 1 for some devices. And if I unplug/replug a device using
> > fakephp, numa_node becomes correct (1 instead of 0). This just looks
> > like the code is there but things are initialized in the wrong order.
>
> do you have
> ...
> bus 00 -> pxm 0 -> node 0
> ...
> bus 40 -> pxm 1 -> node 1
> ...
> bus 80 -> pxm 1 -> node 1
>
> in your boot msg or dmesg?
>
> if not, your dsdt doesn't have _PXM for pci root bus. or you need to
> ask your HW vendor to add that in their BIOS, or use my patchset.

please try the attached patchset

please get x86.git then use quilt apply the patch

http://people.redhat.com/mingo/x86.git/README

YH

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