Re: coding for optimizations (Re: [PATCH 1/2] i386: mce cleanup part1: functional change)

Oleg Verych
2007-10-11T15:59:43Z

On Thu, Oct 11, 2007 at 05:21:30PM +0200, Adrian Bunk wrote:
> On Thu, Oct 11, 2007 at 05:26:09PM +0200, Oleg Verych wrote:
> > On Thu, Oct 11, 2007 at 01:14:29AM +0200, Adrian Bunk wrote:
> > []
> > > It's also a quite ill idea to think about whether gcc might produce a
> > > few bytes more or less code at the if when there's such a long printk()
> > > in the middle...
> >
> > printk() problem was discussed with proper banana userspace replacement
> > proposition by me, so i don't care much.
> >
> > Though, why MCE can't be enabled/disabled by config option? Native
> > engineers from proper company should know what processors have this
> > feature... If kconfig isn't flexible for this, i'm glad to hear
> > opinions. If it's needed anyway, then sorry.
>
> You should better say sorry for not having checked that it can already
> be disabled with a kconfig option...

Talk is not about wana-build-MCE-in, given to the user's sake. But about
flexible selection of this code, if it is really supported by CPU, when
user have it enabled (see winchip/preventium sub-thread). More work, it
is not such quick patch, certainly, but this is needed for famous i386.

I wonder, why such patch wasn't introduced long time ago. Modern
(cheap) chips have no MCE?
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