during potentially stack consuming resource release.
loo_object_free
is called to actually release memory allocated by ->ldo->object_alloc()
+ If the object contains a struct lu_object_header, then it must be
+ freed by call_rcu() or rcu_kfree().
loo_object_release
is called when object last it’s last user and moves onto LRU list of
unused objects. implementation of this method is optional to OSD.