Re: [PATCH 00/05] robust per_cpu allocation for modules

Ravikiran G Thirumalai
2006-04-17T22:01:44Z

On Mon, Apr 17, 2006 at 09:55:02AM -0700, Christoph Lameter wrote:
> On Sat, 15 Apr 2006, Nick Piggin wrote:
>
> > If I'm following you correctly, this adds another dependent load
> > to a per-CPU data access, and from memory that isn't node-affine.
>
> I am also concerned about that. Kiran has a patch to avoid allocpercpu
> having to go through one level of indirection that I guess would no
> longer work with this scheme.

The alloc_percpu reimplementation would work regardless of changes to
static per-cpu areas. But, any extra indirection as was proposed initially
is bad IMHO.

>
> > If so, I think people with SMP and NUMA kernels would care more
> > about performance and scalability than the few k of memory this
> > saves.
>
> Right.

Me too :)

Kiran