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SubjectRe: jiffies rollover, uptime etc.
On Mon, 18 Feb 2002, Ben Greear wrote:

> I wonder, is it more expensive to write all drivers to handle the
> wraps than to take the long long increment hit? The increment is
> once every 10 miliseconds, right? That is not too often, all things
> considered...

This is just a matter of getting the signed/unsigned declarations right in
comparisons. (time_before and time_after macros were introduced to aid
here, hint!)
No overhead is involved here.

Actually, quite a few bug fixes in this area went into 2.4.18pre, with
some more to come in 2.4.19pre.

>
> Maybe the non-atomicity of the long long increment is the problem?

Yes.

> Does this problem still exist on 64-bit machines?
>

No.

> THanks,
> Ben

Tim

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