Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754795AbYHSGim (ORCPT ); Tue, 19 Aug 2008 02:38:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752752AbYHSGid (ORCPT ); Tue, 19 Aug 2008 02:38:33 -0400 Received: from one.firstfloor.org ([213.235.205.2]:54333 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751718AbYHSGid (ORCPT ); Tue, 19 Aug 2008 02:38:33 -0400 To: Shaohua Li Cc: lkml , Andrew Morton , Ingo Molnar , "Pallipadi, Venkatesh" Subject: Re: [patch]pageattr: cache flush before tlb flush From: Andi Kleen References: <1219026451.16428.4.camel@sli10-desk.sh.intel.com> Date: Tue, 19 Aug 2008 08:38:28 +0200 In-Reply-To: <1219026451.16428.4.camel@sli10-desk.sh.intel.com> (Shaohua Li's message of "Mon, 18 Aug 2008 10:27:31 +0800") Message-ID: <877iad1pcr.fsf@basil.nowhere.org> User-Agent: Gnus/5.1008 (Gnus v5.10.8) Emacs/21.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 651 Lines: 16 Shaohua Li writes: > clflush uses a virtual address but cache line is physical indexed in > x86. In my understanding, clflush will do some pagetable walk, so doing > cache flush first should reduce some pagetable walk. The SDM describes the exact sequence how this should be done. Linux unfortunately skips one step currently, but it's not a good idea to diverge even more. -Andi -- 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/