On Wed, 20 Oct 1999, [iso-8859-1] Rub�n wrote:
> On 1999/Oct/20, Brian S. Julin wrote:
>
> > Basically there are two situations to worry about. One is trying
> > to find the ray position from userspace when the process is running.
> > The other is trying to get the scheduler to run the process
> > promptly at a certain ray positions.
>
> I think there is an easy solution for the first thing. Why don't you
> share a flag variable between the kernel and the process, that becomes 1 at
> the vertical retrace and 0 when it finishes? It would be for programmers
> even more efficient than reading from the IO port directly (which is
> impossible under Linux, obviously). It could be managed in a similar way
> than the graphics context, couldn't it?
I think that putting this flag in the context map is the way to
go. The flag can be quickly toggled by the interrupt handler, and nothing
else is necessary. This doesn't get around the scheduling Hz problem, but
that is a separate issue anyway, and needs to be fixed for a lot more than
just GGI.
Jon
---
'Cloning and the reprogramming of DNA is the first serious step in
becoming one with God.'
- Scientist G. Richard Seed
