On Thu 14 Sep 2017, Eric Anholt wrote: > Jason Ekstrand <ja...@jlekstrand.net> writes: > > > The setTexBuffer2 hook from GLX is used to implement glxBindTexImageEXT > > which has tighter restrictions than just "it's shared". In particular, > > it says that any rendering to the image while it is bound causes the > > contents to become undefined. This means that we can do whatever aux > > tracking we want between glxBindTexImageEXT and glxReleaseTexImageEXT so > > long as we always transition from external in Bind and to external in > > Release. > > The intent of the spec was to get at the hard-to-define "you get pixels > at least as new as the outstanding X11 rendering when you called > glxBindTexImageEXT(), but if X11 keeps on rendering to the thing then > you may get newer pixels, too." With your CCS plan and X11 rendering in > parallel with you GL texturing from the X11 pixmap, will we always see > either old or new pixels but not anything else?
We have bigger problems if X11 today renders to any surface that has been externally shared with I915_FORMAT_MOD_Y_TILED_CCS. If I ran git-grep correctly, then xf86-video-intel nor xf86-video-modesetting is unaware of modifiers and hence unaware of CCS aux state. So, with respect to reviewing this patch, I think it's safe to assume that X11 never renders to a CCS-enabled surface, and that this patch is the correct fix. If X11 does render to CCS-enabled surfaces, then we have more invasive problems that need fixing. Reviewed-by: Chad Versace <chadvers...@chromium.org> _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
