Re: First cut of PowerPC support in NPTL

[Ian Wienand <ianw gelato unsw edu au>]

On Fri, Mar 07, 2003 at 11:20:16AM +1100, Paul Mackerras wrote:
> I have been working on adding support for PowerPC in NPTL.  The patch
> below shows where I am up to with it.  I am sending it out at this
> stage in the hope of getting some useful comments and criticism, even
> though it is not finished or working yet. 

Hi,

I have an IA64 port that is a few inches futher along (just some
tricky problems when I clone) that I haven't been brave enough to
release (it's also not against the latest release).

I think before either of these goes too much futher it might be good
to abstract lowlevellock.h more.  All that is really system dependent
is an atomic_increment / atomic_decrement and a compare and swap for
the trylock.  I would leave the ia32 (optimised asm) and s390 ports
(uses compare and swap to do inc/dec) alone, but we should both use
generic versions, as we're basically doing the same thing.

If there's no objections over the next few days I might update my
non-complete ia64 version to the latest code and move as much as i can
into generic, then we can work on tweaking it?  My implementation of
the locking is described in

http://www.gelato.unsw.edu.au/IA64wiki/lowlevellock.h

if I have anything wrong, please edit the document.

-i
ianw gelato unsw edu au
http://www.gelato.unsw.edu.au