[PATCH -rt] powerpc update

Daniel Walker dwalker at mvista.com
Thu Oct 19 00:52:08 EST 2006


On Wed, 2006-10-18 at 16:33 +0200, Ingo Molnar wrote:
> * Daniel Walker <dwalker at mvista.com> wrote:
> 
> > On Wed, 2006-10-18 at 09:28 +0200, Ingo Molnar wrote:
> > > * Daniel Walker <dwalker at mvista.com> wrote:
> > > 
> > > > Pay close attention to the fasteoi interrupt threading. I added usage 
> > > > of mask/unmask instead of using level handling, which worked well on 
> > > > PPC.
> > > 
> > > this is wrong - it should be doing mask+ack.
> > 
> > The main reason I did it this way is cause the current threaded eoi 
> > expected the line to be masked. So if you happen to have a eoi that's 
> > threaded you get a warning then the interrupt hangs.
> 
> does that in fact happen on -rt6? If yes, could you send the warning 
> that is produced?
> 
> 	Ingo

The warning was the WARN_ON_ONCE from the section below (which is gone
is -rt6)

        if (redirect_hardirq(desc)) {
-               WARN_ON_ONCE(1);
+               mask_ack_irq(desc, irq);
                goto out_unlock;
        }
+

I haven't tried it, but I'd think it will work. That's assuming you have
an "ack" which I hear some PowerPC don't (Benjamin Herrenschmidt talked
about having no "ack" when discussing fasteoi a few month back).

Daniel




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