[Intel-gfx] [PATCH 10/15] drm/i915: Assert that machine is wedged for nop_submit_request

[Michel Thierry]

On 17/07/17 02:11, Chris Wilson wrote:
> We should only ever do nop_submit_request when the machine is wedged, so
> assert it is so.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> ---
>   drivers/gpu/drm/i915/i915_gem.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index ca7a56ff3904..5517373c1bea 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -3089,6 +3089,7 @@ void i915_gem_reset_finish(struct drm_i915_private *dev_priv)
>   
>   static void nop_submit_request(struct drm_i915_gem_request *request)
>   {
> +	GEM_BUG_ON(!i915_terminally_wedged(&request->i915->gpu_error));
>   	dma_fence_set_error(&request->fence, -EIO);
>   	i915_gem_request_submit(request);
>   	intel_engine_init_global_seqno(request->engine, request->global_seqno);
> 

Not sure about this, your patch before this one, ("[PATCH 09/15] 
drm/i915: Wake up waiters after setting the WEDGED bit"), is moving the 
set_bit after engine_set_wedged:

@@ -3157,10 +3157,12 @@ static int __i915_gem_set_wedged_BKL(void *data)
  	struct intel_engine_cs *engine;
  	enum intel_engine_id id;

-	set_bit(I915_WEDGED, &i915->gpu_error.flags);
  	for_each_engine(engine, i915, id)
  		engine_set_wedged(engine);

+	set_bit(I915_WEDGED, &i915->gpu_error.flags);
+	wake_up_all(&i915->gpu_error.reset_queue);
+
  	return 0;
  }

I don't think it won't hit the BUG_ON because i915_gem_set_wedged is 
already protected by stop_machine. Anyway it looks odd.

-Michel