On Mon, 2014-11-17 at 12:24 -0800, Alexander Duyck wrote: > Yes and no. So for example on ARM I used the dmb() operation, however > I > have to use the barrier at the system level instead of just the inner > shared domain. However on many other architectures they are just the > same as the smp_* variants. > > Basically the resultant code is somewhere between the smp and non-smp > barriers in terms of what they cover. There I don't quite follow you. You need to explain better especially in the documentation because otherwise people will get it wrong... If it's ordering in the coherent domain, I fail to see how a DMA agent is different than another processor when it comes to barriers, so I fail to see the difference with smp_* I understand the MMIO vs. memory issue, we do have the same on powerpc, but that other aspect eludes me. Ben. -- 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