
SwapBuffers will implicitly flush the query along with the other GPU work for the frame. The comment was about this function being called for direct scanout, which hasn't been the case since 56580ea7c941 ("backends/native: Assume zero rendering time for direct scanout buffers"). This eliminates one GPU work flush to the kernel per frame with the Mesa radeonsi driver, leaving only a single flush per frame. Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/4158>