Re: [ANNOUNCE] 3.0.14-rt31 - ksoftirq running wild - FEC ethernet driver to blame? Yep

[Steven Rostedt <rostedt@goodmis.org>]

On Wed, 2012-01-18 at 14:54 +0100, Mike Galbraith wrote:
> On Wed, 2012-01-18 at 12:11 +0100, Tim Sander wrote:
> 
> > > If that's it, you can apply the below, do the same edit, and see which
> > > thread is grinding away.  From there, I'd set a trap.  Let sirq threads
> > > detect that they are being awakened too fast (hey, I can't go to sleep,
> > > the sirq I just processed is busy again, N times in a row) and leave a
> > > note for wakeup_softirqd().  There, WARN_ON(ksoftirqd)[i].help_me) or
> > > such, to see who is flogging which softirq mercilessly.
> > I didn't use this tricks, since top was already doing its job good enough :-).
> 
> Ok, you now know which softirq is being flogged, maybe that's enough for
> someone who knows network goop, dunno.  If you set the trap, you'll get
> an 8x10 color glossy of the slave driver, whip in hand ;-)

This could be another trylock spin loop. I'll have to have a deeper
look.

Thanks,

-- Steve