On Tue, 3 Jun 2008, Nick Piggin wrote: > > Linus: on x86, memory operations to wc and wc+ memory are not ordered > with one another, or operations to other memory types (ie. load/load > and store/store reordering is allowed). Also, as you know, store/load > reordering is explicitly allowed as well, which covers all memory > types. So perhaps it is not quite true to say readl/writel is strongly > ordered by default even on x86. You would have to put in some > mfence instructions in them to make it so. Well, you have to ask for WC/WC+ anyway, so it's immaterial. A driver that does that needs to be aware of it. IOW, it's a non-issue, imnsho. Linus -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
