Re: [Patch 1/4] Delay accounting: Initialization

[Marcelo Tosatti]

On Mon, Nov 14, 2005 at 08:20:17PM -0800, Andrew Morton wrote:
> Shailabh Nagar <nagar@xxxxxxxxxxxxxx> wrote:
> >
> > +	*ts = sched_clock();
> 
> I'm not sure that it's kosher to use sched_clock() for fine-grained
> timestamping like this.  Ingo had issues with it last time this happened?  

If the system boots with use_rtc == 0 you're going to get jiffies based
resolution from sched_clock(). I have a 1GHz Pentium 3 around here which
does that.

Maybe use do_gettimeofday() for such systems?

Would be nice to have a sort of per-arch overridable "gettime()" function?

> <too lazy to read all the code> Do you normalise these numbers in some
> manner before presenting them to userspace?  If so, by what means?
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