vn_instance_roundtrip does 2 things:
1. vn_instance_submit_roundtrip
- before: encode a cmd to write vq seqno to ring extra field
- after: encode a cmd to update vq seqno against a ring
- submit the encoded cmd via vq
2. vn_instance_wait_roundtrip
- before: wait until ring extra field has the vq seqno
- after: let renderer ring thread wait for the vq seqno
Signed-off-by: Yiwei Zhang <zzyiwei@chromium.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21716>
Yiwei Zhang
1cb42a629f