Re: [RFC] exponential update_wall_time

From: john stultz
Date: Wed Sep 27 2006 - 19:20:43 EST


On Wed, 2006-09-27 at 15:05 -0700, Andrew Morton wrote:
> On Wed, 27 Sep 2006 12:35:33 -0700
> john stultz <johnstul@xxxxxxxxxx> wrote:
>
> > + while (offset > clock->cycle_interval << (shift + 1))
> > + shift++;
>
> hurts my brain.

Yea. Its not the most obvious patch, but the complexity is pretty
isolated.

> I have a vague feeling that this can be done with
> something like ffz(~(offset/clock->cycle_interval))+epsilon, but that hurts
> my brain too.

Agreed. I don't want to obfuscate this code much more. In my opinion,
the loop is tightly bounded and not expensive enough to try to optimize.

thanks
-john


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