On Thu, Apr 17, 2014 at 11:03:56AM -0400, Waiman Long wrote: > @@ -192,36 +220,25 @@ void queue_spin_lock_slowpath(struct qspinlock *lock, u32 val) > node->next = NULL; > > /* > + * We touched a (possibly) cold cacheline; attempt the trylock once > + * more in the hope someone let go while we weren't watching as long > + * as no one was queuing. > */ > + if (!(val & _Q_TAIL_MASK) && queue_spin_trylock(lock)) > + goto release; But you just did a potentially very expensive op; @val isn't representative anymore! -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
