Re: do_gettimeofday( ) precision?

[Lukasz Michal Rak]

On Wed, 23 Jun 2004, abhijit wrote:

> hello,
>
> the comment on top of do_gettimeofday( ) [arch/i386/kernel/time.c] says:
>
> /*
>  * This version of gettimeofday has microsecond resolution
>  * and better than microsecond precision on fast x86 machines with TSC.
>  */
> void do_gettimeofday(struct timeval *tv)
> {
> ...
>
> but the code below limits usec to <= 1000000. so isn't the resolution
> not limited to microsec even on TSC capable boxes?
>
> if one wants higher resolution (for timestamping etc.) whats the preferred
> way?
>
> thanks
> abhijit

	Hi!

 I think you are right that do_gettimeofday() is limited to microsec even
on boxes with TSC register. This function returns only seconds and
microseconds so you won't get better resolution with it. I don't know the
way how to do it, but I wonder about precision of such mechanism (if any
exists).
 Regards,

		Lukasz
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