How about getting rid of that TICKET_MSB mess and doing something like: #define TICKET_MASK 0xFFFF static inline void ticket_spin_unlock(atomic_t *tickets) { u32 t = *tickets; smp_mb__before_atomic_inc(); /* Increment the low 16 bits without affecting the upper. */ if (unlikely((~t & TICKET_MASK) == 0)) atomic_add(-(atomic_t)TICKET_MASK, tickets); else atomic_inc(tickets); } That also allows up to 2^16 waiters, up from 2^15. (Minus one on both cases, if you want to be fussy.) -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html