Re: [RFC][PATCH] Change pcibus_to_cpumask() to pcibus_to_node()

[Matthew Dobson <colpatch@us.ibm.com>]

On Tue, 2004-07-27 at 08:57, Andi Kleen wrote:
> On Tue, 27 Jul 2004 08:15:39 -0700
> Jesse Barnes <jbarnes@engr.sgi.com> wrote:
> 
> > On Tuesday, July 27, 2004 7:16 am, Andi Kleen wrote:
> > > On Mon, 26 Jul 2004 17:10:08 -0700
> > >
> > > Matthew Dobson <colpatch@us.ibm.com> wrote:
> > > > So in discussions with Jesse at OLS, we decided that pcibus_to_node() is
> > > > a more generally useful function than pcibus_to_cpumask().  If anyone
> > > > disagrees with that, now would be a good time to let us know.
> > >
> > > Not sure that is a good idea. Sometimes this information is not available.
> > > With pcibus_to_cpumask() the fallback is obvious, but it isn't with
> > > pcibus_to_node(). Returning a random node is wrong.
> > 
> > Hmm... so there's no way for you to get a node or nodemask at all?
> 
> When the BIOS has _PXM methods there will be probably.
> Just I cannot guarantee it has that, so there should be some clean fallback path.
> 
> If cpumask is too complicated for you a pcibus_to_nodemask would be fine
> for me too, just please no single node number.
> 
> 
> -Andi

I guess I'm OK with a nodemask instead of a node.  That will make this
patch dependent on my nodemask_t patch, which I'll also be sending out
again later today, though...  A nodemask instead of a node also allows
us to return a mask of nearby memory-only nodes as well as CPU-only
nodes, if the arch supports that, for allocating buffers/doing DMA
from...

-Matt