RCU_GP_FLAG_FQS
if (*gfp & RCU_GP_FLAG_FQS)
if (READ_ONCE(rcu_state.gp_flags) & RCU_GP_FLAG_FQS) {
WRITE_ONCE(rcu_state.gp_flags, rcu_state.gp_flags & ~RCU_GP_FLAG_FQS);
(gf & (RCU_GP_FLAG_FQS | RCU_GP_FLAG_OVLD))) {
WRITE_ONCE(rcu_state.gp_flags, rcu_state.gp_flags | RCU_GP_FLAG_FQS);
ret = (READ_ONCE(rcu_state.gp_flags) & RCU_GP_FLAG_FQS) ||
if (READ_ONCE(rcu_state.gp_flags) & RCU_GP_FLAG_FQS) {
WRITE_ONCE(rcu_state.gp_flags, rcu_state.gp_flags | RCU_GP_FLAG_FQS);