Re: [PATCH 9/11] Panic delay fix

[Pavel Machek]

Hi!

> >>We'd have to audit and figure out what udelays are for hardware and
> >>which are not, but the evidence is that the vast majority of them are
> >>for hardware and not needed for virtualization.
> >>    
> >
> >Which is irrelevant since the hardware drivers won't be used in a
> >virtualised environment with any kind of performance optimisation.
> >  
> 
> Which is why an audit is irrelevant for the most part.  Note on the 
> performance below.

You know it is ugly. Alan demonstrated it even hurts performance, but
being ugly is the main problem.

If you _need_ to avoid udelay() in some cases, introduce
udelay_unless_virtualized(), and switch few users to it. Just globaly
defining udelay to nop is _ugly_.
								Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/