Subject: Re: hash-table creation...

From: Benjamin Herrenschmidt <[email-masked]>
Date: Sun, 08 Feb 2009 08:17:00 +1100

On Sat, 2009-02-07 at 11:43 +0530, sumedh tirodkar wrote:
> Hello,
> 
> I wanted algorithm for creating hash tables used in paging mechanism..
> In the manual that i read i got algorithm to convert Effective Address
> to Real Address using these hash tables that are created..but i could
> not find how these hash tables are created in first place using the
> Real addresses.
> Is there any document available for the same?

There's one MMU hash table. It's allocated & cleared by the kernel
during early boot or by the hypervisor and pointed to by the SDR1
register.

It's populated by code in arch/powerpc/mm/hash_low_64.S or
hash_low_32.S, typically as the result of a hash miss exception.

Ben.