Re: [PATCH 05/13] drm/i915: introduce i915_hangcheck_ring_hung

[Ben Widawsky <ben@bwidawsk.net>]

On Tue, Feb 26, 2013 at 01:05:08PM +0200, Mika Kuoppala wrote:
> In preparation to track per ring progress in hangcheck,
> add i915_hangcheck_ring_hung.
> 
> Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
> ---
>  drivers/gpu/drm/i915/i915_irq.c |   31 +++++++++++++++++++------------
>  1 file changed, 19 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
> index de5af12..b828807 100644
> --- a/drivers/gpu/drm/i915/i915_irq.c
> +++ b/drivers/gpu/drm/i915/i915_irq.c
> @@ -1771,28 +1771,35 @@ static bool kick_ring(struct intel_ring_buffer *ring)
>  	return false;
>  }
>  
> +static bool i915_hangcheck_ring_hung(struct drm_device *dev,
> +				     struct intel_ring_buffer *ring)
> +{
> +	if (!IS_GEN2(dev)) {
> +		/* Is the chip hanging on a WAIT_FOR_EVENT?
> +		 * If so we can simply poke the RB_WAIT bit
> +		 * and break the hang. This should work on
> +		 * all but the second generation chipsets.
> +		 */
> +		return !kick_ring(ring);
> +	}
> +
> +	return false;
> +}
> +
>  static bool i915_hangcheck_hung(struct drm_device *dev)
>  {
>  	drm_i915_private_t *dev_priv = dev->dev_private;
>  
>  	if (dev_priv->gpu_error.hangcheck_count++ > 1) {
>  		bool hung = true;
> +		struct intel_ring_buffer *ring;
> +		int i;
>  
>  		DRM_ERROR("Hangcheck timer elapsed... GPU hung\n");
>  		i915_handle_error(dev, true);
>  
> -		if (!IS_GEN2(dev)) {
> -			struct intel_ring_buffer *ring;
> -			int i;
> -
> -			/* Is the chip hanging on a WAIT_FOR_EVENT?
> -			 * If so we can simply poke the RB_WAIT bit
> -			 * and break the hang. This should work on
> -			 * all but the second generation chipsets.
> -			 */
> -			for_each_ring(ring, dev_priv, i)
> -				hung &= !kick_ring(ring);
> -		}
> +		for_each_ring(ring, dev_priv, i)
> +			hung &= i915_hangcheck_ring_hung(dev, ring);
>  
>  		return hung;
>  	}

I don't think you need dev. Just bail early if it's GEN2. If you really
need dev later, you can get it from ring->dev.

-- 
Ben Widawsky, Intel Open Source Technology Center