Re: BogoMIPS
Martin Mares (mj@ucw.cz)
Tue, 29 Sep 1998 09:36:45 +0200
> I did the same thing for 2.0.x a long time ago. It helped for certain
> chips, but it still jittered for others. And it depended on how the kernel
> got compiled - there was one (German?) person in particular who took the
> bogomips loop into user code and tried it with tons of different
> placements, and showed that for his CPU it made a difference how it was
> placed and what the surrounding code was.
>
> As a result, 2.0.x just does it as a separate subroutine in
>
> arch/i386/lib/delay.S
>
> and that pretty much forces it to not jitter at all. If you'd send me that
> kind of patch I'd accept it.
We already do it as a separate subroutine in 2.1 -- see arch/i386/lib/delay.c :-)
Maybe adding align to the start of the loop should be even better...
Have a nice fortnight
--
Martin `MJ' Mares <mj@ucw.cz> http://atrey.karlin.mff.cuni.cz/~mj/
Faculty of Math and Physics, Charles University, Prague, Czech Rep., Earth
"Black holes are where God divided by zero."
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