On Wed, 2014-02-26 at 10:22 +0100, Peter Zijlstra wrote: > On Tue, Feb 25, 2014 at 11:56:19AM -0800, Jason Low wrote: > > On Mon, 2014-02-10 at 20:58 +0100, Peter Zijlstra wrote: > > > + for (;;) { > > > + if (prev->next == node && > > > + cmpxchg(&prev->next, node, NULL) == node) > > > + break; > > > + > > > + /* > > > + * We can only fail the cmpxchg() racing against an unlock(), > > > + * in which case we should observe @node->locked becomming > > > + * true. > > > + */ > > > + if (smp_load_acquire(&node->locked)) > > > + return true; > > I've stuck on in right about here. So that we don't unduly delay the > cmpxchg() after the load of prev.
Ok. Reviewed-by: Jason Low <jason.l...@hp.com> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/