On Wed, Aug 25, 2021 at 03:47:12PM +0300, Ville Syrjälä wrote: > On Wed, Aug 25, 2021 at 12:49:25AM +0000, Souza, Jose wrote: > > On Thu, 2021-08-19 at 19:07 +0300, Ville Syrjälä wrote: > > > On Wed, Aug 18, 2021 at 07:48:03PM +0000, Souza, Jose wrote: > > > > On Wed, 2021-08-18 at 17:55 +0300, Ville Syrjälä wrote: > > > > > On Tue, Aug 17, 2021 at 05:42:15PM -0700, José Roberto de Souza wrote: > > > > > > By now all the userspace applications should have migrated to atomic > > > > > > or at least be calling DRM_IOCTL_MODE_DIRTYFB. > > > > > > > > > > > > With that we can kill frontbuffer rendering support in i915 for > > > > > > modern platforms. > > > > > > > > > > > > So here converting legacy APIs into atomic commits so it can be > > > > > > properly handled by driver i915. > > > > > > > > > > > > Several IGT tests will fail with this changes, because some tests > > > > > > were stressing those frontbuffer rendering scenarios that no userspace > > > > > > should be using by now, fixes to IGT should be sent soon. > > > > > > > > > > Blocking atomic commits instead of the current lightweight frontbuffer > > > > > interface sounds like a terrible plan. How unusable is X with this > > > > > approach? > > > > > > > > 100% usable, had no issues when running X in TGL and ADL-P. > > > > Added a debug message in intel_user_framebuffer_dirty() and X is not even using frontbuffer rendering at all. > > > > > > Turn off your compositor if you want to test front buffer rendering. > > > > Worked fine on Plasma with a 4K panel, was not able to find how to do that in Gnome. > > I didn't think you can turn off composition with either one of those. > You actually confirmed it's running with everytithing unredirected and > eg. there was no lag moving windows around and wiggling the mouse? > > Avoiding that lag is pretty much the sole reason why the legacy > cursor unsynced update stuff even exists in the driver. Hard to > imagine you wouldn't hit the same issue with the server getting > blocked on dirtyfb all the time. Oh and running x11perf/etc. to see the impact on the raw numbers would probably be good idea. -- Ville Syrjälä Intel
