[Intel-gfx] Prevent trivial oom from gem_exec_nop/sequential

[Chris Wilson]

Quoting Tvrtko Ursulin (2018-01-16 09:52:10)
> 
> On 15/01/2018 21:24, Chris Wilson wrote:
> > About the third resend of this series that tries to curtail the prolonged
> > reference lifetimes of fences via the signaler thread when the CPUs are
> > saturated by interrupts.
> 
> Happens on CI, regularly, occasionally?

It would if CI ran the longer running tests that expose the problems.
Even at nop rates it still takes 30s or so to exhaust memory on a small
device (obviously highly dependent on individual configurations and
device timings).
-Chris