Wayland's Weston Gets Patch For High Priority GPU Support

Last year Intel open-source developers squared away priority GPU scheduling support within their kernel DRM driver and from Mesa are exposing support for "high priority" GPU processes via the EGL_IMG_context_priority extension. There hasn't been any major real-world user of this support yet, but a patch would allow Wayland's Weston OpenGL renderer to make use of it.

Chris Wilson of Intel who was also involved in the driver's GPU priority scheduling support has now added support to libweston's OpenGL renderer code to make use of EGL_IMG_context_priority when available.

This makes sense here for trying to eliminate input-output jitter and a smoother user-interface by trying to ensure the compositor's rendering process gets higher priority access on the GPU in order to minimize output latency.

The patch is straight-forward and will hopefully be merged soon for libweston. The EGL_IMG_context_priority extension only provides a hint though to the GPU that it wants high priority access and the GPU can always decide to assign normal priority depending upon the conditions.

Update: The work has now been merged into Weston master on 1 March.