Re: [patch] voluntary-preempt-2.6.8.1-P1

Thomas Charbonnel
2004-08-18T12:25:38Z

Ingo Molnar wrote :
> * Ingo Molnar <mingo@elte.hu> wrote:
>
> > > Yes, Ingo identified an issue with copy_page_range, I don't think it's
> > > fixed yet. See the voluntary-preempt-2.6.8.1-P0 thread.
> >
> > right, it's not fixed yet. It's not a trivial critical section - we
> > are holding two locks and are mapping two atomic kmaps.
>
> fortunately it's easier than i thought - neither the source pmd nor the
> target pmd can go away so we can simply drop the locks, reschedule, and
> remap. Does the patch below (ontop of -P3) fix the copy_page_range()
> latencies you are seeing?
>
> Ingo
>

Ooops, sorry about my previous post, I had missed this one. It fixes the
problem, thanks.

Thomas