On Thu, May 03, 2018 at 11:19:32AM +0530, Satendra Singh Thakur wrote: > In the func drm_atomic_set_crtc_for_plane, with the current code, > if crtc of the plane_state and crtc passed as argument to the func > are same, entire func will executed in vein. > It will get state of crtc and clear and set the bits in plane_mask. > All these steps are not required for same old crtc. > Ideally, we should do nothing in this case, this patch handles the same, > and causes the program to return without doing anything in such scenario. > > Signed-off-by: Satendra Singh Thakur <satendra.t@xxxxxxxxxxx> > Cc: Madhur Verma <madhur.verma@xxxxxxxxxxx> > Cc: Hemanshu Srivastava <hemanshu.s@xxxxxxxxxxx> > --- > drivers/gpu/drm/drm_atomic.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c > index 7d25c42..5bd3365 100644 > --- a/drivers/gpu/drm/drm_atomic.c > +++ b/drivers/gpu/drm/drm_atomic.c > @@ -1421,7 +1421,9 @@ drm_atomic_set_crtc_for_plane(struct drm_plane_state *plane_state, > { > struct drm_plane *plane = plane_state->plane; > struct drm_crtc_state *crtc_state; > - > + /* Nothing to do for same crtc*/ > + if (plane_state->crtc == crtc) > + return 0; I didn't do this (both here and in the set_crtc_for_connector functions) because the overhead is probably way down in the noise compared to the overall atomic commit machinery. Do you really see this as a hotpath? -Daniel > if (plane_state->crtc) { > crtc_state = drm_atomic_get_crtc_state(plane_state->state, > plane_state->crtc); > -- > 2.7.4 > > _______________________________________________ > dri-devel mailing list > dri-devel@xxxxxxxxxxxxxxxxxxxxx > https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel