On Tue, Nov 13, 2018 at 03:52:44PM -0500, Sean Paul wrote: > From: Sean Paul <seanpaul@xxxxxxxxxxxx> I neglected to add --cover-letter to send-email, so pasting my cover here instead: Hi all, So I kept digging into the locking and dependencies around encoder/crtc and this is the latest series to pop out. I think things are a bit more clear and safe at the end. We have now gotten rid of the crtc_lock and the pm_runtime sync operations in vblank enable/disable, so we should be able to completely turf the display thread/worker/etc! Note that this series applies on top of [1]. Thanks! Sean [1]- https://lists.freedesktop.org/archives/dri-devel/2018-November/196170.html > > There are 4 times that _dpu_crtc_vblank_enable_no_lock() is called: > > 1- crtc enable > 2- crtc disable > 3- crtc vblank enable > 4- crtc vblank disable > > When we enable or disable the crtc, we call drm_crtc_vblank_on and > drm_crtc_vblank_off respectively. That will gate vblank enables and > disables to only being called when the crtc is active. That means that > we can just enable/disable pm runtime in crtc enable/disable. This will > be beneficial in trying to eliminate blocking calls from the vblank call > chain. > > Signed-off-by: Sean Paul <seanpaul@xxxxxxxxxxxx> > --- > drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c > index 80de5289ada3..aa2f20c05dd7 100644 > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c > @@ -777,8 +777,6 @@ static void _dpu_crtc_vblank_enable_no_lock( > struct drm_encoder *enc; > > if (enable) { > - pm_runtime_get_sync(dev->dev); > - > list_for_each_entry(enc, &dev->mode_config.encoder_list, head) { > if (enc->crtc != crtc) > continue; > @@ -801,8 +799,6 @@ static void _dpu_crtc_vblank_enable_no_lock( > > dpu_encoder_register_vblank_callback(enc, NULL, NULL); > } > - > - pm_runtime_put_sync(dev->dev); > } > } > > @@ -902,6 +898,8 @@ static void dpu_crtc_disable(struct drm_crtc *crtc) > crtc->state->event = NULL; > spin_unlock_irqrestore(&crtc->dev->event_lock, flags); > } > + > + pm_runtime_put_sync(crtc->dev->dev); > } > > static void dpu_crtc_enable(struct drm_crtc *crtc, > @@ -917,6 +915,8 @@ static void dpu_crtc_enable(struct drm_crtc *crtc, > } > priv = crtc->dev->dev_private; > > + pm_runtime_get_sync(crtc->dev->dev); > + > DRM_DEBUG_KMS("crtc%d\n", crtc->base.id); > dpu_crtc = to_dpu_crtc(crtc); > > -- > Sean Paul, Software Engineer, Google / Chromium OS > -- Sean Paul, Software Engineer, Google / Chromium OS
