Re: early printk timings way off

[Jesper Juhl <jesper.juhl@gmail.com>]

On 9/16/05, Tim Schmielau <tim@physik3.uni-rostock.de> wrote:
> 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.
> 

Thanks Tim, much appreciated.

-- 
Jesper Juhl <jesper.juhl@gmail.com>
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