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Subject: Re: [PATCH] r8169: Reduce looping in the interrupt handler.
From: David Dillow <dave@thedillows.org>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Francois Romieu <romieu@fr.zoreil.com>,
       Michael Riepe <michael.riepe@googlemail.com>,
       Michael Buesch <mb@bu3sch.de>, Rui Santos <rsantos@grupopie.com>,
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Date: Wed, 26 Aug 2009 09:59:35 -0400
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On Wed, 2009-08-26 at 09:56 -0400, David Dillow wrote:
> On Wed, 2009-08-26 at 00:58 -0700, Eric W. Biederman wrote:
> > diff --git a/drivers/net/r8169.c b/drivers/net/r8169.c
> > index 3b19e0c..2214945 100644
> > --- a/drivers/net/r8169.c
> > +++ b/drivers/net/r8169.c
> 
> > +
> > +		/* Ignore the parts of status that reflect more than
> > +		 * the enabled interrupts.
> > +		 */
> > +		smp_rmb();
> > +		if (!(status & tp->intr_mask & tp->intr_event))
> > +			break;
> >  	}
> 
> This looks like an odd construct, since we're just about to go back the
> while condition up top -- why not just mask it here and let the loop
> handle it naturally?

Never mind, I see what you are doing -- avoiding a false loop if we get
status == 0xffff. I still don't like the aesthetics of it, but it makes
sense, and I'll blame it on the card. :)

I should really get some caffeine before posting...