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SubjectRe: time interpolation hooks
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On Fri, 2003-05-16 at 14:23, Andrew Morton wrote:
> Gents, the below patch comes from David M-T, out of the ia64 tree. It may
> be a suitable solution to the "gettimeofday goes backwards when interrupts
> were blocked" problem.
>
> It will need per-arch support. I'm not sure what that looks like; maybe
> David can outline what the reset/update functions should do?

Yea, I'd like to see a sample reset/update implementation as well.

Right now in i386 land we do the compensation for lost ticks in
mark_offset_tsc/cyclone. The reason for this is that every interrupt we
only want to read the high-res timesource once in order to avoid any
atomicity issues. So all the interpolation and compensation has to
happen in the same place (or atleast using the same data).

I probaly need to spend some more time looking over this. However the
sample implementation would likely give me the "aha!" i need.

thanks
-john


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