We need to synchronize main (CCS/BCS) and companion rcs batch, so let's
create an empty batch and make both the batches (CCS/BCS) and companion
RCS batch wait on empty sync batch and signal the fence.
Reason to execute the empty batch is we need to make sure the companion
RCS batch finish as soon as the CCS/BCS batch finish. Preemption could
prevent the companion RCS batch execution and we might end up destroying
the CCS/BCS batch before companion RCS finishes.
Signed-off-by: Sagar Ghuge <sagar.ghuge@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/23661>