[Intel-gfx] [PATCH] drm/i915/selftests: Bump the scheduling threshold for fast heartbeats

[Chris Wilson]

Quoting Mika Kuoppala (2021-01-13 14:13:57)
> Chris Wilson <chris at chris-wilson.co.uk> writes:
> 
> > Since we are system_highpri_wq, we expected the heartbeat to be
> > scheduled promptly. However, we see delays of over 10ms upsetting our
> > assertions. Accept this as inevitable and bump the error threshold to
> > 20ms (from 6ms).
> >
> > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> > ---
> >  drivers/gpu/drm/i915/gt/selftest_engine_heartbeat.c | 13 ++++++++++---
> >  1 file changed, 10 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/gt/selftest_engine_heartbeat.c b/drivers/gpu/drm/i915/gt/selftest_engine_heartbeat.c
> > index b88aa35ad75b..e88a01390dc5 100644
> > --- a/drivers/gpu/drm/i915/gt/selftest_engine_heartbeat.c
> > +++ b/drivers/gpu/drm/i915/gt/selftest_engine_heartbeat.c
> > @@ -197,6 +197,7 @@ static int cmp_u32(const void *_a, const void *_b)
> >  
> >  static int __live_heartbeat_fast(struct intel_engine_cs *engine)
> >  {
> > +     const int error_threshold = max(20000, jffies_to_usecs(6));
> 
> s/jffies/jiffies
> 
> Also for the commit message, 6 jiffies are not 6ms so it needs
> some mending.

Ok, might as well pull the failure messages from CI as well for a bit
more information.
-Chris