On Tue, Jan 29, 2013 at 06:13:35PM +0200, ville.syrj...@linux.intel.com wrote: > From: Ville Syrjälä <ville.syrj...@linux.intel.com> > > Someone may be waiting for a flip that will never complete due to a GPU > reset. Wake up all such waiters when the hang is first detected, and > after the reset processing has finished. > > Signed-off-by: Ville Syrjälä <ville.syrj...@linux.intel.com> > --- > drivers/gpu/drm/i915/i915_irq.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c > index 13bb8d3..8b1146b 100644 > --- a/drivers/gpu/drm/i915/i915_irq.c > +++ b/drivers/gpu/drm/i915/i915_irq.c > @@ -915,6 +915,8 @@ static void i915_error_work_func(struct work_struct *work) > for_each_ring(ring, dev_priv, i) > wake_up_all(&ring->irq_queue); > > + wake_up_all(&dev_priv->pending_flip_queue); > + > wake_up_all(&dev_priv->gpu_error.reset_queue); > } > } > @@ -1540,6 +1542,8 @@ void i915_handle_error(struct drm_device *dev, bool > wedged) > */ > for_each_ring(ring, dev_priv, i) > wake_up_all(&ring->irq_queue); > + > + wake_up_all(&dev_priv->pending_flip_queue);
I don't quite follow why we need this one here. The wake up for the ring irq queues is to get people off the dev->struct_mutex lock, which the reset handler needs to acquire to do its job. But process stalling for pageflips to complete already can't hold dev->struct_mutex, since otherwise they'd block out the pageflip completion works and so would deadlock already. Is there another reason why we need to kick waiters before the reset has completed that I'm missing here? One potential issue would be clarifying what exactly happens when the gpu hangs while pageflipping, i.e. whether the kernel should go out of it's way and re-issue the pageflip if it died meanwhile. But even that could be scheduled from a workqueue I think. And even if that'd require us to kick waiters of the pending flip queue I'd prefer to only add it once we really need it (plus a big comment explaining the tricks). -Daniel > } > > queue_work(dev_priv->wq, &dev_priv->gpu_error.work); > -- > 1.7.12.4 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
