Enabling interrupt filters by default

[John Baldwin]

On Wednesday 15 April 2009 4:36:30 pm Marcel Moolenaar wrote:
> 
> On Apr 15, 2009, at 1:13 PM, John Baldwin wrote:
> 
> > On Wednesday 15 April 2009 2:04:14 pm Marcel Moolenaar wrote:
> >>
> >> On Apr 15, 2009, at 10:24 AM, John Baldwin wrote:
> >>
> >>> A while ago I changed the interrupt code in 8.x such that all the MD
> >>> code was
> >>> the same for both the INTR_FILTER and non-INTR_FILTER case.  I would
> >>> like to
> >>> flip the switch to enable INTR_FILTER by default.  Any objections?
> >>
> >> Last time it was found to be not working. Did we fix it?
> >
> > Err, when was that?
> 
> August 2007.

I rototilled all the MD interrupt code to make both the filter and !filter MD 
code identical and both sets use the same callout routines (post_filter, 
etc.) in April 2008.
 
> >  I know folks have used it on amd64 and i386 ok and I have
> > tested it on both of those platforms.  One of the arm kernel configs  
> > uses it
> > by default.
> 
> There was interrupt starvation on sparc64. There were also
> issues with permanently masking stray interrupts. This is
> problematic when interrupts are shared and there is at least
> 1 filter on it.
> 
> FYI,

The MD interrupt code has changed quite a bit since then and I explicitly 
worked with marius@ and others to test the aforementioned changes (though 
various platforms may have only tested the !filter case at the time).

-- 
John Baldwin