Re: [RFC 1/4] time: export getnstime_raw_and_real for DRM

[Imre Deak <imre.deak@intel.com>]

On Fri, 2012-10-05 at 12:14 -0400, Kristian Høgsberg wrote:
> On Fri, Oct 5, 2012 at 9:36 AM, Imre Deak <imre.deak@intel.com> wrote:
> > Needed by the upcoming DRM raw monotonic timestamp support.
> 
> I just had a quick look at driver/input/evdev.c, since evdev devices
> did a similar change recently to allow evdev timestamp from the
> monotonic clock.  They're using a different time API:
> 
> 	time_mono = ktime_get();
>         time_real = ktime_sub(time_mono, ktime_get_monotonic_offset());
> 
> and
> 
>         event->time = ktime_to_timeval(client->clkid == CLOCK_MONOTONIC ?
> 			                mono : real);
> 
> I'm not really up-to-date on kernel time APIs, but I wonder if that
> may be better?  At least, I suspect we wouldn't need changes outside
> drm if we use this API.


Thanks, I will use this instead of getnstime_raw_and_real.

The reason is as discussed on #intel-gfx that this provides a monotonic
vs. raw monotonic time and that as you say it won't require a change in
the time keeping code.

--Imre

> 
> Kristian
> 
> 
> > Signed-off-by: Imre Deak <imre.deak@intel.com>
> > ---
> >  kernel/time/timekeeping.c |    2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
> > index d3b91e7..073d262 100644
> > --- a/kernel/time/timekeeping.c
> > +++ b/kernel/time/timekeeping.c
> > @@ -365,7 +365,7 @@ void ktime_get_ts(struct timespec *ts)
> >  }
> >  EXPORT_SYMBOL_GPL(ktime_get_ts);
> >
> > -#ifdef CONFIG_NTP_PPS
> > +#if defined(CONFIG_NTP_PPS) || defined(CONFIG_DRM) || defined(CONFIG_DRM_MODULE)
> >
> >  /**
> >   * getnstime_raw_and_real - get day and raw monotonic time in timespec format
> > --
> > 1.7.9.5
> >


_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/dri-devel