From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756804AbbAZUFR (ORCPT ); Mon, 26 Jan 2015 15:05:17 -0500 Received: from mga14.intel.com ([192.55.52.115]:47219 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756648AbbAZUFP (ORCPT ); Mon, 26 Jan 2015 15:05:15 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.09,470,1418112000"; d="scan'208";a="656729685" Message-ID: <54C69DF9.1090702@intel.com> Date: Mon, 26 Jan 2015 12:05:13 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 MIME-Version: 1.0 To: Ross Zwisler CC: linux-kernel@vger.kernel.org, Ingo Molnar , Thomas Gleixner , Borislav Petkov Subject: Re: [PATCH v2 0/2] add support for new persistent memory instructions References: <1422045628-16225-1-git-send-email-ross.zwisler@linux.intel.com> <54C2D34D.7010709@intel.com> <1422301899.13382.2.camel@theros.lm.intel.com> In-Reply-To: <1422301899.13382.2.camel@theros.lm.intel.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/26/2015 11:51 AM, Ross Zwisler wrote: > > This is fine, but now you've got two fences in a row. Another slightly more > messy choice would be to include the fence in the pcommit assembly, so > you either get pcommit + sfence or a pair of NOPs. > If that is the required usage pattern, it should be part of the clwb() inline at least. -hpa