Originally, the function always executes do_idling() followed by undo_idling() regardless of whether obj->has_dma_mapping is TRUE or not. This change idles the GPU only if needed. However, if the intention of the function is to ALWAYS idle the GPU, then my change is a mistake. - Armin -----Original Message----- From: Chris Wilson [mailto:chris@xxxxxxxxxxxxxxxxxx] Sent: Friday, July 11, 2014 10:20 AM To: Reese, Armin C Cc: intel-gfx@xxxxxxxxxxxxxxxxxxxxx Subject: Re: [PATCH] drm/i915: Optimize the i915_gem_gtt_finish_object function On Fri, Jul 11, 2014 at 10:15:36AM -0700, armin.c.reese@xxxxxxxxx wrote: > From: Armin Reese <armin.c.reese@xxxxxxxxx> > > Signed-off-by: Armin Reese <armin.c.reese@xxxxxxxxx> > --- > drivers/gpu/drm/i915/i915_gem_gtt.c | 13 ++++++------- > 1 file changed, 6 insertions(+), 7 deletions(-) > > diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c > b/drivers/gpu/drm/i915/i915_gem_gtt.c > index afd4eef..7e2190e 100644 > --- a/drivers/gpu/drm/i915/i915_gem_gtt.c > +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c > @@ -1624,18 +1624,17 @@ static void ggtt_unbind_vma(struct i915_vma > *vma) > > void i915_gem_gtt_finish_object(struct drm_i915_gem_object *obj) { > - struct drm_device *dev = obj->base.dev; > - struct drm_i915_private *dev_priv = dev->dev_private; > - bool interruptible; > - > - interruptible = do_idling(dev_priv); > + if (!obj->has_dma_mapping) { > + struct drm_device *dev = obj->base.dev; > + struct drm_i915_private *dev_priv = dev->dev_private; > + bool interruptible = do_idling(dev_priv); > > - if (!obj->has_dma_mapping) > dma_unmap_sg(&dev->pdev->dev, > obj->pages->sgl, obj->pages->nents, > PCI_DMA_BIDIRECTIONAL); > > - undo_idling(dev_priv, interruptible); > + undo_idling(dev_priv, interruptible); > + } Are you really beating the compiler here? -Chris -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
