Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262072AbTI0D6l (ORCPT ); Fri, 26 Sep 2003 23:58:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262105AbTI0D6l (ORCPT ); Fri, 26 Sep 2003 23:58:41 -0400 Received: from rth.ninka.net ([216.101.162.244]:43186 "EHLO rth.ninka.net") by vger.kernel.org with ESMTP id S262072AbTI0D6k (ORCPT ); Fri, 26 Sep 2003 23:58:40 -0400 Date: Fri, 26 Sep 2003 20:57:33 -0700 From: "David S. Miller" To: davidm@hpl.hp.com Cc: davidm@napali.hpl.hp.com, ak@muc.de, linux-kernel@vger.kernel.org Subject: Re: NS83820 2.6.0-test5 driver seems unstable on IA64 Message-Id: <20030926205733.7942a74e.davem@redhat.com> In-Reply-To: <16244.31648.766419.56901@napali.hpl.hp.com> References: <16244.31648.766419.56901@napali.hpl.hp.com> X-Mailer: Sylpheed version 0.9.5 (GTK+ 1.2.10; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 26 Sep 2003 10:47:12 -0700 David Mosberger wrote: > Arches that don't like/support unaligned accesses will certainly > have a copy_user() which handles misalignment just fine. For > example, on ia64, the copy will run slightly slower because of an > additional shift in the loop, but that penalty only shows on fully > cached data. Exactly correct, and on many platforms (sparc64 happens to be one) there is _ZERO_ performance penalty for misalignment or source or destination buffer during a memcpy/memmove. - 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/