Re: [RFC] Reverting NUMA-affine page table allocation

[Ingo Molnar <mingo@elte.hu>]

* Tejun Heo <tj@kernel.org> wrote:

> Hello,
> 
> On Wed, Mar 02, 2011 at 08:47:54AM -0800, Yinghai Lu wrote:
> > > > Yeah, it's a pretty interesting piece of code in need of some cleanup.
> > No, i mean second one is not causing any problem.
> > 
> > that only take end is intentionally. that will make sure we can get
> > space for page table even in extreme case.
> 
> Hmmm... it seems like it only took @end because it always allocated
> the whole page table in one go.  Always from the bottom to top.  Am I
> missing something?
> 
> > > > If you're interested in doing the above, please go ahead and let me
> > > > know.
> > 
> > No. please don't revert it.
> > 
> > Ingo, please get patches that will align to 1G ... from
> > 
> > 	git://git.kernel.org/pub/scm/linux/kernel/git/yinghai/linux-2.6-yinghai.git memblock
> 
> If you were gonna do that, you could have just said that you objected
> to the reverting.  The message was Request for Comments - soliciting
> responses.
> 
> As I wrote multiple times, I think the code as implemented is a bit
> heavy handed for the problem.  And a bigger problem for me is that it
> kind of just piles on the existing messiness and worsens it.  I really
> hope we wouldn't be doing that anymore.
> 
> I tried to clean up the page table allocation code but the necessary
> changes felt a bit too large at this stage, so IMO that's best left to
> the next cycle.

Do you plan to implement it more cleanly?

> To me, it seems complicated for not good enough reasons.  I'll defer
> the decision to x86 maintainers.  Ingo, hpa, Thomas, what do you guys
> think?

Would be nice to see an actual patch that does the revert.

Thanks,

	Ingo