On Thu, Jul 06, 2017 at 08:21:10AM -0700, Paul E. McKenney wrote: > And yes, there are architecture-specific optimizations for an > empty spin_lock()/spin_unlock() critical section, and the current > arch_spin_unlock_wait() implementations show some of these optimizations. > But I expect that performance benefits would need to be demonstrated at > the system level. I do in fact contended there are any optimizations for the exact lock+unlock semantics. The current spin_unlock_wait() is weaker. Most notably it will not (with exception of ARM64/PPC for other reasons) cause waits on other CPUs. -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html