Re: NOHZ: local_softirq_pending 08

From: Dave Jones
Date: Thu May 31 2012 - 10:04:35 EST


On Thu, May 31, 2012 at 09:56:25AM +0200, Eric Dumazet wrote:
> On Thu, 2012-05-31 at 09:52 +0200, Thomas Gleixner wrote:
> > Dave,
> >
> > On Wed, 30 May 2012, Dave Jones wrote:
> >
> > > May 30 17:43:04 [ 1095.335659] NOHZ: local_softirq_pending 08
> > >
> > > According to git, you ratelimited this back in 2007 with the message
> > > "until we found the root cause of that problem."
> > >
> > > Is this an old problem that has returned ?
> >
> > Looks like.
> >
> > > Maybe interesting note: Both machines I see this on regularly are Atom cpus,
> > > and it's always '08'.
> >
> > So it goes idle with NET_RX softirq pending. That really should not
> > happen. I fear you need to fire up the tracer :)
>
> It might be a bug in the network driver, a race with NAPI completion.
>
> Dave, which net drivers run on these machines ?

r8169.

I got an email from someone else asking if I used Realtek drivers, which I thought
was an uncanny guess.

Dave
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