From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755044AbbL3Uqv (ORCPT ); Wed, 30 Dec 2015 15:46:51 -0500 Received: from shards.monkeyblade.net ([149.20.54.216]:39342 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753728AbbL3Uqs (ORCPT ); Wed, 30 Dec 2015 15:46:48 -0500 Date: Wed, 30 Dec 2015 15:46:46 -0500 (EST) Message-Id: <20151230.154646.596597479469584255.davem@davemloft.net> To: mst@redhat.com Cc: linux-kernel@vger.kernel.org, peterz@infradead.org, arnd@arndb.de, linux-arch@vger.kernel.org, andrew.cooper3@citrix.com, virtualization@lists.linux-foundation.org, stefano.stabellini@eu.citrix.com Subject: Re: [PATCH 00/34] arch: barrier cleanup + __smp_xxx barriers for virt From: David Miller In-Reply-To: <1451473761-30019-1-git-send-email-mst@redhat.com> References: <1451473761-30019-1-git-send-email-mst@redhat.com> X-Mailer: Mew version 6.7 on Emacs 24.5 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Wed, 30 Dec 2015 12:46:48 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Michael S. Tsirkin" Date: Wed, 30 Dec 2015 14:58:19 +0200 > -. Patch 1 documents the __smp APIs, and explains why they are > useful for virt If virt is doing things like interacting with descriptors that are shared with a (potentially SMP) host, why don't we just annotate those specific cases? The other memory barriers in the kernel do not matter for SMP'ness when build UP.