RSL
#define LOCK RSL
#define RLOCK RSL
#define RLOCK RSL
RSL(X1);
RSL(X1); // this one should fail
RSL(X1);
RSL(X2); // this one should fail
RSL(X1);
RSL(X2); // this one should fail
RSL(X1);
RSL(X1);
RSL(X1);