[okl4-developer] SMP in OKL4

[Nelson Tam]

Hi Jamie,

On 14/02/2008, at 11:14 AM, Jamie Lennox wrote:

> I know not all versions of L4 support SMP, however i've always had  
> it in
> my head that OKL4 was multi-entrant. But when looking through the trap
> code there is no interrupt disabling but no locking of critical
> sections, or at least that i could see. I'm pretty sure its wrapped up
> in the continuations but reading through the ia32 code they seem to be
> passed around more than ever actually set.
>
> Can someone give me a run-down on how the kernel handles multiple
> requests and possibly the continuation model, where they are invoked.


Unfortunately the publicly available version of OKL4 currently only
supports uni-processor targets.  Rest assured that multi-processing
is very important to us, and we do in fact have multi-processing
versions of OKL4 developed internally that our roadmap calls for
maturing and releasing in the short-medium term (sorry, can't be
more precise than that at this stage).

If you have any specific questions regarding the design of what would
be a multi-processing enabled version of OKL4, feel free to shoot away.
I'll help as best I can (for example, I can point out that our design
generally steers away from using locks and uses atomic operations
where possible, for improved scalability).

--
(nt)

Nelson Tam
nelson at ok-labs.com