Re: [PATCH] drm/i915: Don't die in wait_for_pending_flips

[Jesse Barnes <jbarnes@virtuousgeek.org>]

On Mon, 19 May 2014 16:09:35 +0200
Daniel Vetter <daniel.vetter@ffwll.ch> wrote:

> We can apperently miss them, but breaking the entire driver hampers
> testing. So bail out after one minute, our customerary "this is a lost
> cause" timeout.
> 
> References: https://bugs.freedesktop.org/show_bug.cgi?id=78383
> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> ---
>  drivers/gpu/drm/i915/intel_display.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 0f8f9bcb3012..6eca24d8b282 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -3284,8 +3284,9 @@ static void intel_crtc_wait_for_pending_flips(struct drm_crtc *crtc)
>  
>  	WARN_ON(waitqueue_active(&dev_priv->pending_flip_queue));
>  
> -	wait_event(dev_priv->pending_flip_queue,
> -		   !intel_crtc_has_pending_flip(crtc));
> +	WARN_ON(wait_event_timeout(dev_priv->pending_flip_queue,
> +				   !intel_crtc_has_pending_flip(crtc),
> +				   60*HZ) == 0);
>  
>  	mutex_lock(&dev->struct_mutex);
>  	intel_finish_fb(crtc->primary->fb);

Updating our page flip ioctl man page (hah!) with the timeout info
would be good, in case people like Mario queue flips for after lunch. :)

-- 
Jesse Barnes, Intel Open Source Technology Center