On Wed, Mar 08, 2023 at 03:29:45PM +0100, Maarten Lankhorst wrote: > Hey, > > > On 2023-03-08 14:36, Ville Syrjälä wrote: > > On Wed, Mar 08, 2023 at 01:47:12PM +0100, Maarten Lankhorst wrote: > >> On 2023-03-06 21:58, Ville Syrjälä wrote: > >>> On Mon, Mar 06, 2023 at 09:23:50PM +0100, Maarten Lankhorst wrote: > >>>> Hey, > >>>> > >>>> On 2023-03-06 16:23, Souza, Jose wrote: > >>>>> On Mon, 2023-03-06 at 15:16 +0100, Maarten Lankhorst wrote: > >>>>>> As a fallback if we decide not to merge the frontbuffer tracking, allow > >>>>>> i915 to keep its own implementation, and do the right thing in Xe. > >>>>>> > >>>>>> The frontbuffer tracking for Xe is still done per-fb, while i915 can > >>>>>> keep doing the weird intel_frontbuffer + i915_active thing without > >>>>>> blocking Xe. > >>>>> Please also disable PSR and FBC with this or at least add a way for users to disable those features. > >>>>> Without frontbuffer tracker those two features will break in some cases. > >>>> FBC and PSR work completely as expected. I don't remove frontbuffer > >>>> tracking; I only remove the GEM parts. > >>>> > >>>> Explicit invalidation using pageflip or CPU rendering + DirtyFB continue > >>>> to work, as I validated on my laptop with FBC. > >>> Neither of which are relevant to the removal of the gem hooks. > >>> > >>> Like I already said ~10 times in the last meeting, we need a proper > >>> testcase. Here's a rough idea what it should do: > >>> > >>> prepare a batch with > >>> 1. spinner > >>> 2. something that clobbers the fb > >>> > >>> Then > >>> 1. grab reference crc > >>> 2. execbuffer > >>> 3. dirtyfb > >>> 4. wait long enough for fbc to recompress > >>> 5. terminate spinner > >>> 6. gem_sync > >>> 7. grab crc and compare with reference > >>> > >>> No idea what the current status of PSR+CRC is, so not sure > >>> whether we can actually test PSR or not. > >> This test doesn't make sense. DirtyFB should simply not return before > >> execbuffer finishes. > > Of course it should. It's not a blocking ioctl, and can't > > be because that will make X unusable. > > Except it actually is. > > DirtyFB blocks in its default implementation, and waits for the next vblank. > > drm_atomic_helper_dirtyfb() blocks by default as it's a synchronous > plane update. > > Considering every driver except i915 uses it, it works just fine. :) No it doesn't. We tries to use it, but that was an utter failure. -- Ville Syrjälä Intel