Subject: Re: I think I have 8xx working...

From: Benjamin Herrenschmidt <[email-masked]>
Date: Thu, 15 Oct 2009 12:12:50 +1100

On Wed, 2009-10-14 at 18:08 -0700, Rex Feany wrote:
> Thus spake Benjamin Herrenschmidt ([email-masked]):
> 
> > On Wed, 2009-10-14 at 17:41 -0700, Rex Feany wrote:
> > > The biggest problem for me turned out to be the MMU context IDs being
> > > clamped to 32 when the 8xx only has 16. With this, things are a bit more
> > > stable :)
> > 
> > This is with Joakim patches or without ?
> 
> with just one: adding tlbil_va() to do_page_fault().

Ah cool, at least that keeps my sanity, I didn't get how it could work
at all without that bit :-)

Scott, Joakim: It will be interesting to figure out exactly what is the
condition where that is necessary. It definitely should make the one
in set_pte_filter() or ptep_set_access_flags_filter() unnecessary.

Joakim, you mentioned increased amount of TLB errors or misses when
doing that too often, that sounds a bit weird and worth investigating

Finally we could implement preload from update_mmu_cache() but that's a
different matter alltogether.

Cheers,
Ben.