Introduce COMMIT_RING() as in radeon DRM, stop using error prone writeback
drwxr-xr-x - bsd-core
drwxr-xr-x - bsd
drwxr-xr-x - libdrm
drwxr-xr-x - linux-core
drwxr-xr-x - linux
drwxr-xr-x - shared-core
drwxr-xr-x - shared
drwxr-xr-x - tests