
Recent changes to ptr_ring broke the ringtest
which lacks a likely() stub. Fix it up.
Fixes: 982fb490c2
("ptr_ring: support zero length ring")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Partial implementation of various ring layouts, useful to tune virtio design. Uses shared memory heavily. Typical use: # sh run-on-all.sh perf stat -r 10 --log-fd 1 -- ./ring