Re: [PATCH] tsc-disable_B9

[Alan Cox <alan@lxorguk.ukuu.org.uk>]

On Wed, 2002-08-21 at 18:17, Andrea Arcangeli wrote:
> > Fixed in the -ac tree for the non APM triggered case because we use
> > cpufreq code
> 
> if the reduced loops is supposed to work fine what was there left to fix?

Support for doing it right in case someone finds a marginal component
where it doesnt. Incidentally the APM case is it appears fixable.

> > And you can test that with notsc. Oh and you might also want the code
> > that makes notsc on a tsc only kernel print a warning btw. badtsc lets
> > you say "I have a brain cell" notsc lets you select "clueless app
> > checking mode"
> 
> what's wrong with a sysctl to specify you have a brain cell? I'm not
> advocating not to let you specify you have a brain cell, I'm only don't
> see why we should assume it when we very know apps will break silenty,
> and that it will be not noticeable except with subtle breakage after
> some runtime in -ac.

The default behaviours are unchanged. badtsc is simply an extra mode. If
anything the new tree is far better because "notsc" on a 686 kernel
actually warns people it is being ignored. Thats the important bit.
Badtsc is just a handy thing.