From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1423106AbXD3HZr (ORCPT ); Mon, 30 Apr 2007 03:25:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1423110AbXD3HZq (ORCPT ); Mon, 30 Apr 2007 03:25:46 -0400 Received: from public.id2-vpn.continvity.gns.novell.com ([195.33.99.129]:48223 "EHLO gwia-smtp.id2.novell.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1423106AbXD3HZp convert rfc822-to-8bit (ORCPT ); Mon, 30 Apr 2007 03:25:45 -0400 Message-Id: <4635B62D.76E4.0078.0@novell.com> X-Mailer: Novell GroupWise Internet Agent 7.0.1 Date: Mon, 30 Apr 2007 08:26:05 +0100 From: "Jan Beulich" To: "Bryan O'Sullivan" , "Andi Kleen" Cc: "Roland Dreier" , , Subject: Re: [patches] [PATCH] [8/35] x86_64: a memcpy that tries to reducecache pressure References: <20070428752.712152000@suse.de> <20070428175232.5A688151CA@wotan.suse.de> In-Reply-To: <20070428175232.5A688151CA@wotan.suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org >+ testb $8, %dxl /* rdx is 3,5,6,7,9..15 */ Could you use the more conventional name %dl (or whatever is being meant) here? >+.L42: >+ prefetchnta 128(%rsi) I think I commented similarly on a previous version of the patch: This will - result in still bringing the first 128 bytes into the cache - prevent caching of memory beyond the buffer being dealt with >+ sfence Similarly, I continue to believe this is wrong here (again I commented before that this is likely unnecessary, or if at all, it should be an lfence). >+ orl %edx, %edx Operations of this type generally should use 'test', not 'or' or 'and'. Jan