[Intel-gfx] [RFC PATCH] drm/i915: Suppress page allocation warnings on engine park

[Chris Wilson]

Quoting Janusz Krzysztofik (2020-04-02 11:28:03)
> On Thu, 2020-04-02 at 11:21 +0100, Chris Wilson wrote:
> > Quoting Janusz Krzysztofik (2020-04-02 11:19:06)
> > > On memory constrained systems it may happen that no pages are available
> > > for serving object creation attempt during engine park.  Since we can
> > > and we do ignore that failure, let's suppress possible warnings from
> > > page allocator to avoid confusion and make CI happy.
> > 
> > The effect of ignoring it though is dangerous, hence why I had a
> > warning.
> 
> Then maybe just WARN() from switch_to_kernel_context() on
> __i915_request_create() returning -ENOMEM instead?

The warning exists already. The only real question is what to do about
it; the best answer would be to preallocate the final request during
unpark where we can report an error, but that would take a bit more
effort to refactor request allocation. Hence the warning to make it a
futureselves problem.
-Chris