Re: [PATCH]O18.1int

Con Kolivas
2003-08-25T12:21:44Z

On Mon, 25 Aug 2003 21:58, Måns Rullgård wrote:
> Con Kolivas <kernel@kolivas.org> writes:
> >> >> Vanilla test1 has the spin effect. Test2 doesn't. I haven't tried
> >> >> vanilla test3 or test4. As I've said, the O16.2-O16.3 patch
> >> >> introduced the problem. With that patch reversed, everything is
> >> >> fine. What problem does that patch fix?
> >> >
> >> > It's a generic fix for priority inversion but it induces badness in
> >> > smp, and latency in task preemption on up so it's not suitable.
> >>
> >> Now I'm confused. If that patch is bad, then why is it in O18?
> >
> > No, the 16.2 patch is bad. 16.3 backed it out.
>
> OK, but it somehow made XEmacs behave badly.

Well it was a generic fix in 16.2 that helped XEmacs as I said. O15 also had a
generic fix (child not preempting it's parent) but that too was covering up
the real issue, but it wasnt as drastic as 16.2.

Con