Il 17/06/2014 00:08, Waiman Long ha scritto:
+void __pv_queue_unlock(struct qspinlock *lock) +{ + int val = atomic_read(&lock->val); + + native_queue_unlock(lock); + + if (val & _Q_LOCKED_SLOW) + ___pv_kick_head(lock); +} +Again a race can happen here between the reading and writing of the lock value. I can't think of a good way to do that without using cmpxchg.
Could you just use xchg on the locked byte? Paolo _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
