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Subject: Re: [PATCH/RFC] net: Add __napi_sycnhronize() to sync with napi poll
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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Tue, 16 Oct 2007 17:37:03 +1000

> 
> On Tue, 2007-10-16 at 14:06 +0800, Herbert Xu wrote:
> > Benjamin Herrenschmidt <benh@kernel.crashing.org> wrote:
> > >
> > > Note: I use msleep_interruptible(1); just like napi_disable(). However
> > > I'm not too happy that the "hot" loop that results of a pending signal
> > > here will spin without even a cpu_relax ... what do you guys think would
> > > be the best way to handle this ?
> > 
> > Well since the loop does not check signals at all, it should
> > just use msleep.
> > 
> > Granted the process will end up in the D state and contribute
> > to the load average.  But if this loop executes long enough
> > for that to be noticed then we've got bigger problems to worry
> > about.
> 
> If Dave & Stephen agree, I'll send a patch changing napi_disable() too
> then.

I agree with the msleep() change.