On Fri, Nov 02, 2012 at 03:25:59PM +0000, Chris Wilson wrote: > On Thu, 1 Nov 2012 20:06:00 +0200, [email protected] wrote: > > From: Ville Syrjälä <[email protected]> > > > > intel_pipe_set_base() never actually waited for any pending page flips > > on the CRTC. It looks like it tried to, by calling intel_finish_fb() on > > the current front buffer. But the pending flips were actually tracked > > in the BO of the previous front buffer, so the call to intel_finish_fb() > > never did anything useful. > > > > Now even the pending_flip counter is gone, so we should just > > use intel_crtc_wait_for_pending_flips(), but since we're already holding > > struct_mutex when we would call that function, we need another version > > of it, that itself doesn't lock struct_mutex. > > > > Signed-off-by: Ville Syrjälä <[email protected]> > > --- > > drivers/gpu/drm/i915/intel_display.c | 51 > > +++++++++++++++++++++------------ > > 1 files changed, 32 insertions(+), 19 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/intel_display.c > > b/drivers/gpu/drm/i915/intel_display.c > > index 1a38267..7bf4749 100644 > > --- a/drivers/gpu/drm/i915/intel_display.c > > +++ b/drivers/gpu/drm/i915/intel_display.c > > @@ -2228,6 +2228,37 @@ static void intel_crtc_update_sarea_pos(struct > > drm_crtc *crtc, int x, int y) > > } > > } > > > > +static bool intel_crtc_has_pending_flip(struct drm_crtc *crtc) > > +{ > > + struct drm_device *dev = crtc->dev; > > + struct drm_i915_private *dev_priv = dev->dev_private; > > + unsigned long flags; > > + bool pending; > > + > > + if (atomic_read(&dev_priv->mm.wedged)) > > + return false; > > + > > + spin_lock_irqsave(&dev->event_lock, flags); > > + pending = to_intel_crtc(crtc)->unpin_work != NULL; > > + spin_unlock_irqrestore(&dev->event_lock, flags); > > + > > + return pending; > > +} > > + > > +static void intel_crtc_wait_for_pending_flips_locked(struct drm_crtc *crtc) > > +{ > > Can we rearrange this such that the waiting logic is inside _locked() > and then intel_crtc_wiat_for_pending_flips() becomes a wrapper that > acquires the struct_mutex and then calls _locked()? Just to keep the > code simpler at the expense of the pathological case.
Yeah that looks doable. It does mean we'll be holding struct_mutex around the wait_event() always. As I was already doing that for the panning case, doing the same in the crtc_disable() case shouldn't be any worse. But now I started to wonder a bit about the performance implications of keeping struct_mutex locked for that long... -- Ville Syrjälä Intel OTC _______________________________________________ Intel-gfx mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/intel-gfx
