if (wait_loops >= RCU_QS_ACTIVE_ATTEMPTS) {
uatomic_dec(&gp_futex);
/* Write futex before read reader_gp */
smp_mb_master(RCU_MB_GROUP);
if (wait_loops >= RCU_QS_ACTIVE_ATTEMPTS) {
uatomic_dec(&gp_futex);
/* Write futex before read reader_gp */
smp_mb_master(RCU_MB_GROUP);