[Intel-gfx] [v1 03/10] drm/i915: context submission pvmmio optimization

[Chris Wilson]

Quoting Xiaolin Zhang (2018-10-11 07:14:05)
> It is performance optimization to reduce mmio trap numbers from 4 to
> 1 durning ELSP porting writing (context submission).
> 
> When context subission, to cache elsp_data[4] values in
> the shared page, the last elsp_data[0] port writing will be trapped
> to gvt for real context submission.
> 
> Use PVMMIO_ELSP_SUBMIT to control this level of pvmmio optimization.
> 
> v1: rebase
> v0: RFC
> 
> Signed-off-by: Xiaolin Zhang <xiaolin.zhang at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_vgpu.c |  2 ++
>  drivers/gpu/drm/i915/intel_lrc.c | 37 ++++++++++++++++++++++++++++++++++++-

Hint: intel_vgpu_submission.c and go wild. You do not need to emulate
execlists at all, an async interface along the lines of guc would
strangely enough be more akin to what you want.
-Chris