[Intel-gfx] [PATCH] drm/i915: Break long iterations for get/put shmemfs pages

[Chris Wilson]

Quoting Joonas Lahtinen (2018-11-06 10:55:32)
> Quoting Chris Wilson (2018-11-05 19:06:40)
> > As we may have to iterate a few thousand elements to acquire and release
> > the shmemfs backing storage for a GPU object, we need to break up the
> > long loop with cond_resched() to retain a modicum of low latency for
> > other processes.
> > 
> > Testcase: igt/benchmarks/gem_syslatency
> > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> > Cc: Kuo-Hsin Yang <vovoy at chromium.org>
> > Cc: Matthew Auld <matthew.auld at intel.com>
> > Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
> 
> Reviewed-by: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>

Applied as this improves the current syslatency, and further improves
Kuo-Hsin's patch.
-Chris