Re: early printk timings way off

[Tim Schmielau]

On Fri, 16 Sep 2005, Tim Schmielau wrote:

> On Fri, 16 Sep 2005, Jesper Juhl wrote:
> > It also doesn't
> > explain why two lines, the first with timing value 0.000, and the next
> > with 27.121 don't seem to match reality - the *actual* delta between
> > printing those two lines is far lower than 27 seconds.
>
> Yes, this seems to be different, possibly unrelated problem.
> It's interesting that the value jumps _exactly_to_zero_, though.
> Will need to dig into the code...

Did that.
The problem is that printk uses sched_clock() to determine the time, which
just isn't supposed to be a reliable long-time clock. We need to base the
output on a different clock.

Btw, the rate-limiting logic in printk.c looks 'interesting'. Will look
into that, too.

Tim
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