Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752059AbdLBALO (ORCPT ); Fri, 1 Dec 2017 19:11:14 -0500 Received: from mail-io0-f174.google.com ([209.85.223.174]:45895 "EHLO mail-io0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751413AbdLBALL (ORCPT ); Fri, 1 Dec 2017 19:11:11 -0500 X-Google-Smtp-Source: AGs4zMbe+im+tnhixPZmeXZ+6wmmus5BpCUSXZCq0BePP8mM1BVM1uNsCp5EnNnVZlbolsNCpG+N6w== Date: Fri, 1 Dec 2017 17:11:09 -0700 From: Jason Gunthorpe To: "Paul E. McKenney" Cc: linux-kernel@vger.kernel.org, mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com, Doug Ledford , Richard Henderson , Ivan Kokshaysky , Matt Turner , Michael Cree , Andrea Parri , linux-rdma@vger.kernel.org, linux-alpha@vger.kernel.org Subject: Re: [PATCH tip/core/rcu 16/21] drivers/infiniband: Remove now-redundant smp_read_barrier_depends() Message-ID: <20171202001109.GQ7754@ziepe.ca> References: <20171201195053.GA23494@linux.vnet.ibm.com> <1512157876-24665-16-git-send-email-paulmck@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1512157876-24665-16-git-send-email-paulmck@linux.vnet.ibm.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 693 Lines: 19 On Fri, Dec 01, 2017 at 11:51:11AM -0800, Paul E. McKenney wrote: > The smp_read_barrier_depends() does nothing at all except on DEC Alpha, > and no current DEC Alpha systems use Infiniband: > > lkml.kernel.org/r/20171023085921.jwbntptn6ictbnvj@tower I understand DEC Alpha has PCI, and we continue to support several RDMA devices that used the PCI bus. However, the hif1, rdma vt and qib drivers modified in this patch are PCI-Express ONLY. So I think this idea is fine, but would revise the commit message to focus on PCI-E not Infiniband. > drivers/dma/ioat/dma.c | 2 -- > drivers/infiniband/Kconfig | 1 + Did you mean to have ioat/dma.c in this patch? Jason