[Intel-gfx] [PATCH] drm/i915: Default to more lenient force preempt timeout

[Chris Wilson]

Quoting Joonas Lahtinen (2019-11-26 14:14:10)
> + Jason/Ken for Mesa feedback (please look at Bugzilla discussion)
> 
> Quoting Tvrtko Ursulin (2019-11-26 11:32:42)
> > 
> > On 25/11/2019 16:27, Chris Wilson wrote:
> > > Based on a sampling of a number of benchmarks across platforms, by
> > > default opt for a more much lenient timeout so that we should not
> > > adversely affect existing clients.
> > > 
> > > 640ms ought to be enough for anyone.
> > > 
> > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=112169
> > > Fixes: 3a7a92aba8fb ("drm/i915/execlists: Force preemption")
> > > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> > > Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
> > > Cc: Eero Tamminen <eero.t.tamminen at intel.com>
> > > Cc: Dmitry Rogozhkin <dmitry.v.rogozhkin at intel.com>
> > > ---
> > >   drivers/gpu/drm/i915/Kconfig.profile | 2 +-
> > >   1 file changed, 1 insertion(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/Kconfig.profile b/drivers/gpu/drm/i915/Kconfig.profile
> > > index 1799537a3228..c280b6ae38eb 100644
> > > --- a/drivers/gpu/drm/i915/Kconfig.profile
> > > +++ b/drivers/gpu/drm/i915/Kconfig.profile
> > > @@ -25,7 +25,7 @@ config DRM_I915_HEARTBEAT_INTERVAL
> > >   
> > >   config DRM_I915_PREEMPT_TIMEOUT
> > >       int "Preempt timeout (ms, jiffy granularity)"
> > > -     default 100 # milliseconds
> > > +     default 640 # milliseconds
> 
> Maybe just bump to 1000 ms for a good measure.
> 
> 640 ms is already a radical stall.

But 640ms! :)
-Chris