Re: [PATCH] i386: single node SPARSEMEM fix

Magnus Damm
2005-09-08T06:36:29Z

On Wed, 2005-09-07 at 23:11 -0700, Martin J. Bligh wrote:
> >> >> CONFIG_NUMA was meant to (and did at one point) support both NUMA and flat
> >> >> machines. This is essential in order for the distros to support it - same
> >> >> will go for sparsemem.
> >> >
> >> > That's a different issue. The current code works if you boot a NUMA=y
> >> > SPARSEMEM=y machine with a single node. The current Kconfig options
> >> > also enforce that SPARSEMEM depends on NUMA on i386.
> >> >
> >> > Magnus would like to enable SPARSEMEM=y while CONFIG_NUMA=n. That
> >> > requires some Kconfig changes, as well as an extra memory present call.
> >> > I'm questioning why we need to do that when we could never do
> >> > DISCONTIG=y while NUMA=n on i386.
> >>
> >> Ah, OK - makes more sense. However, some machines do have large holes
> >> in e820 map setups - is not really critical, more of an efficiency
> >> thing.
> >
> > Confused. Does all this mean that we want the patch, or not?
>
> >From that POV, nothing urgent, and would require more work to make use
> of it anyway. Not sure if Magnus had another more immediate use for it?

Just wanted to make sure that both versions of setup_memory() behaved in
a similar way and they both called memory_present(). But nothing urgent,
and no immediate use.

/ magnus