[Intel-gfx] [PATCH i-g-t v3] lib/igt_core: Prefer CLOCK_MONOTONIC_RAW

[Joonas Lahtinen]

On ke, 2015-11-18 at 12:28 +0000, Chris Wilson wrote:
> On Wed, Nov 18, 2015 at 02:18:52PM +0200, Joonas Lahtinen wrote:
> > CLOCK_MONOTONIC_RAW is not affected by NTP, so it should be THE
> > clock
> > used for timing execution of tests.
> > 
> > When fetching either the starting or ending time of a test, show
> > the
> > time as -1.000s.
> > 
> > v3:
> > - Do not exit directly from handler (Chris)
> > - Show elapsed time as -1 if it is not calculable
> 
> Aye, that's better for the subtest handling.
> 
> > @@ -832,10 +851,16 @@ static void exit_subtest(const char *result)
> >  {
> >  	struct timespec now;
> >  	double elapsed;
> > +	int err;
> >  
> > -	gettime(&now);
> > -	elapsed = now.tv_sec - subtest_time.tv_sec;
> > -	elapsed += (now.tv_nsec - subtest_time.tv_nsec) * 1e-9;
> > +	err = gettime(&now);
> > +	if (!err && subtest_time.tv_sec != 0 &&
> > +	    subtest_time.tv_nsec != 0) {
> 
> A little paranoid? If we want the paranoia perhaps move it to gettime
> and return an error?
> 

I'm just checking that the starting time which is in the subtest_time
did not fail (which leads to both being zero). I'm not looking at the
now values :)

Regards, Joonas

> -Chris
> 
-- 
Joonas Lahtinen
Open Source Technology Center
Intel Corporation