Re: dynamic-hz

From: Geert Uytterhoeven
Date: Mon Dec 13 2004 - 11:25:45 EST


On Mon, 13 Dec 2004, Pavel Machek wrote:
> > > I'm not sure what the above "scedule_timeout(HZ/10)" is supposed to
> > > do, but the parameter it gets in 1000hz is "100" so I assume this
> > > is because we want to wait for 100ms, and in 1000hz that equals
> > > 100 cycles. Correct?
> >
> > `schedule_timeout(HZ/x)' lets it wait for 1/x'th second.
>
> ...small problem is that for HZ lower than x it does not wait at all
> :-(.

I know. You better use `(HZ+x-1)/x' for delays.
Integer division can be tricky :-)

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
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