Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756673AbYFYXzA (ORCPT ); Wed, 25 Jun 2008 19:55:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750836AbYFYXyx (ORCPT ); Wed, 25 Jun 2008 19:54:53 -0400 Received: from terminus.zytor.com ([198.137.202.10]:53185 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750770AbYFYXyw (ORCPT ); Wed, 25 Jun 2008 19:54:52 -0400 Message-ID: <4862D247.2010709@kernel.org> Date: Wed, 25 Jun 2008 16:18:31 -0700 From: "H. Peter Anvin" Organization: Linux Kernel Organization, Inc. User-Agent: Thunderbird 2.0.0.14 (X11/20080501) MIME-Version: 1.0 To: Arjan van de Ven CC: Jeremy Fitzhardinge , Ingo Molnar , LKML , x86@kernel.org, xen-devel , Stephen Tweedie , Eduardo Habkost , Mark McLoughlin Subject: Re: [PATCH 03 of 36] x86: add memory barriers to wrmsr References: <93c7057b1f4acae501b2.1214367539@localhost> <20080624214441.13202f12@infradead.org> <4862B3E9.50601@goop.org> <20080625153136.2b3b6737@infradead.org> In-Reply-To: <20080625153136.2b3b6737@infradead.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 844 Lines: 29 Arjan van de Ven wrote: >>> >> I suppose, though I would be inclined to put the barriers in the >> wrmsr macro itself to act as documentation. > > > yeah I meant like this: > > static inline void native_write_msr(unsigned int msr, > unsigned low, unsigned high) > { > barrier(); > asm volatile("wrmsr" : : "c" (msr), "a"(low), "d" (high)); > barrier(); > } > > or in the same in the thing that calls this. > Actually, I believe the barrier(); before is actually incorrect, since it would affect the wrmsr() register arguments rather than the wrmsr instruction itself. -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/