Re: [RFC PATCH] Add timer-source of walltime for ftrace

[Steven Rostedt]

On Wed, 19 Aug 2009, KOSAKI Motohiro wrote:

> > +u64 notrace trace_clock_walltime(void)
> > +{
> > +	u32 remainder;
> > +	return base_walltime.tv_sec + div_u64_rem(
> > +			trace_clock() + base_walltime.tv_nsec,
> > +			NSEC_PER_SEC, &remainder);
> > +}
> 
> Why do we need calculate walltime at ring-buffer recordng phase?
> IOW, Why can't we calculate this at displaing time?

Right! We should have something like this:

	return (u64)base_walltime.tv_sec * NSEC_PER_SEC +
		trace_clock() + base_walltime.tv_nsec;

And then we could divide it out later.

And then we could even show more fields in the output and not limit 
ourselves to seconds.

-- Steve

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/