On Fri, Feb 21, 2014 at 06:01:29PM -0500, Peter Hurley wrote: > smp_mb__after_unlock_lock() is only for ordering memory operations > between two spin-locked sections on either the same lock or by > the same task/cpu. Like: > > i = 1 > spin_unlock(lock1) > spin_lock(lock2) > smp_mb__after_unlock_lock() > j = 1 > > This guarantees that the store to j happens after the store to i. > Without it, a cpu can > > spin_lock(lock2) > j = 1 > i = 1 > spin_unlock(lock1) Hmmm? I'm pretty sure that's a full barrier. Local processor is always in order (w.r.t. the compiler). Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe target-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
