Hi! On Wed, Jul 29, 2020 at 04:02:06PM +0100, Dave Stevenson wrote: > Hi Maxime > > On Wed, 8 Jul 2020 at 18:42, Maxime Ripard <maxime@xxxxxxxxxx> wrote: > > > > The vc4 atomic commit loop has an handrolled loop that is basically > > identical to for_each_new_crtc_state, let's convert it to that helper. > > > > Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx> > > --- > > drivers/gpu/drm/vc4/vc4_kms.c | 9 ++++----- > > 1 file changed, 4 insertions(+), 5 deletions(-) > > > > diff --git a/drivers/gpu/drm/vc4/vc4_kms.c b/drivers/gpu/drm/vc4/vc4_kms.c > > index 210cc2408087..717673b18132 100644 > > --- a/drivers/gpu/drm/vc4/vc4_kms.c > > +++ b/drivers/gpu/drm/vc4/vc4_kms.c > > @@ -152,14 +152,13 @@ vc4_atomic_complete_commit(struct drm_atomic_state *state) > > struct drm_device *dev = state->dev; > > struct vc4_dev *vc4 = to_vc4_dev(dev); > > struct vc4_hvs *hvs = vc4->hvs; > > - struct vc4_crtc *vc4_crtc; > > + struct drm_crtc_state *new_crtc_state; > > + struct drm_crtc *crtc; > > int i; > > > > - for (i = 0; i < dev->mode_config.num_crtc; i++) { > > - if (!state->crtcs[i].ptr || !state->crtcs[i].commit) > > - continue; > > + for_each_new_crtc_in_state(state, crtc, new_crtc_state, i) { > > + struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc); > > for_each_new_crtc_in_state doesn't check !state->crtcs[i].commit as > the hand rolled loop did. Sorry, this is my lack of knowledge, but > does that actually make any real difference? > > I see nothing wrong in calling vc4_hvs_mask_underrun multiple times > anyway, so it's most likely going to be harmless anyway, but wanted to > query it. Sorry for not getting back to this earlier. I don't really know :) It looks like the commit pointer is always going to be !NULL in our case: https://elixir.bootlin.com/linux/latest/source/include/drm/drm_crtc.h#L385 The only case where it seems to be checked is when using for_each_old_crtc_in_state, and when the commit pointer is being accessed, and we're in neither of those cases. Since I don't really know though, I guess we can remain on the safe side and keep it for now. Maxime _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel