[Intel-gfx] [PATCH v6 05/20] drm/i915/tdr: Add support for per engine reset recovery

[Chris Wilson]

On Mon, Apr 24, 2017 at 02:22:21PM -0700, Michel Thierry wrote:
> 
> 
> On 20/04/17 17:17, Michel Thierry wrote:
> >>Hmm. Interesting. This relies on i915_gem_retire_requests() (i.e.
> >>struct_mutex) to skip replaying innocent requests, but here we should be
> >>asserting that we do have the hung request.
> >>
> >>i.e.
> >>request = i915_gem_find_active_request(engine);
> >>if (!request)
> >>    goto skip.
> >>
> >>Bonus points for tying that into i915_gem_reset_prepare_engine() so that
> >>we only seach for the active_request once.
> >>
> 
> Will this do it?
> https://patchwork.freedesktop.org/patch/152494/  (ignore the
> DRM_ERROR I still have to change)

That's a little uglier than I was hoping for :(
 
> I'm not sure about reusing the active request in full-reset (what if
> we have more than one engine hung?).

We can have more than one active request, just don't forget a
if (i915_gem_request_completed(engine->hangcheck.hung_request))
	/* skip the reset! */
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre