RCU_GP_FLAG_OVLD
if (*gfp & RCU_GP_FLAG_OVLD)
gf = RCU_GP_FLAG_OVLD;
(gf & (RCU_GP_FLAG_FQS | RCU_GP_FLAG_OVLD))) {
gf = rcu_state.cbovld ? RCU_GP_FLAG_OVLD : 0;