[Intel-gfx] [PATCH 2/2] drm/i915: a couple more uses for i915_gem_object_mark_dirty()

[Chris Wilson]

On Thu, Apr 28, 2016 at 06:20:30PM +0100, Dave Gordon wrote:
> On 28/04/16 17:36, Chris Wilson wrote:
> >On Thu, Apr 28, 2016 at 05:26:21PM +0100, Dave Gordon wrote:
> >>intel_pin_and_map_ringbuffer_obj() should have been setting the dirty
> >>flag, but wasn't; and the LRC code in intel_lr_context_do_pin() is also
> >>updated to use the new function.
> >
> >Technically it doesn't need to. Whilst there is any valid content in the
> >ringbuffer, it is pinned for use by requests and the hadware. Unlike the
> >context object whose content does need to persist when inactive.
> >-Chris
> 
> What about across suspend and/or hibernate? Any chance of there
> being valid (new) content in a ringbuffer that gets thrown away?
> Though presumably we insist that all pending work is completed
> before allowing hibernation/suspend anyway?

Correct, before suspend we wait for all GPU work to be completed. We
don't want the GPU writing into memory after the suspend/hibernation
thinks we are ready. The pages are pinned by our activity as well.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre