Re: Re: [PATCH 1/6][RESEND] xen: Add NUMA support to Xen

[Ryan Harper <ryanh@us.ibm.com>]

* Keir Fraser <Keir.Fraser@cl.cam.ac.uk> [2006-05-15 12:18]:
> 
> On 15 May 2006, at 18:11, Ryan Harper wrote:
> 
> >When I looked at the x86_64 NUMA code, I noticed that SRAT parsing was
> >done by ACPI_NUMA (drivers/acpi/numa.c).  That code requires more ACPI
> >support than Xen currently has available.  Rather than pulling in all 
> >of
> >that ACPI, I chose to start with the i386 SRAT table parser which was
> >sufficient for both i386 and x86_64.  I would think that using the
> >modified i386 srat.c for parser gets the job done without bringing in
> >all of the support needed to compile drivers/acpi/numa.c in Xen.
> >
> >How about putting the two together: use the i386 SRAT parser and the
> >x86_64 srat.c for structures and initialization?
> 
> I guess it depends how cleanly it can be done. Can we use the x86/64 
> logic pretty much unmodified, but then pull in bits of the i386 parsing 
> code as functions that the x86/64 code calls rather than the full-blown 
> acpi routines it would usually call into? Or would it be possible to 
> pull in drivers/acpi/numa.c without also having to pull in all 80kloc+ 
> of acpi crap? This probably needs some thought and/or experimentation!

Well, I *tried* to use drivers/acpi/numa.c first, and I quit after I had
to pull in more than few headers; it was just too intertwined.  I think
using the i386 parser and calling into the x86_64 logic should be
do-able.  I'll give it a go and post back here with the results.

-- 
Ryan Harper
Software Engineer; Linux Technology Center
IBM Corp., Austin, Tx
(512) 838-9253   T/L: 678-9253
ryanh@us.ibm.com