From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261785AbUKUUbG (ORCPT ); Sun, 21 Nov 2004 15:31:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261775AbUKUU3t (ORCPT ); Sun, 21 Nov 2004 15:29:49 -0500 Received: from news.suse.de ([195.135.220.2]:31128 "EHLO Cantor.suse.de") by vger.kernel.org with ESMTP id S261789AbUKUU3e (ORCPT ); Sun, 21 Nov 2004 15:29:34 -0500 To: Adrian Bunk Cc: Adam Belay , Thomas Hood , linux-kernel@vger.kernel.org Subject: Re: What exactly is __ALIGN_STR in pnpbios/bioscalls.c for? References: <20041121175659.GD2924@stusta.de> From: Andreas Schwab X-Yow: Yow! Now I get to think about all the BAD THINGS I did to a BOWLING BALL when I was in JUNIOR HIGH SCHOOL! Date: Sun, 21 Nov 2004 21:29:32 +0100 In-Reply-To: <20041121175659.GD2924@stusta.de> (Adrian Bunk's message of "Sun, 21 Nov 2004 18:56:59 +0100") Message-ID: User-Agent: Gnus/5.110002 (No Gnus v0.2) Emacs/21.3.50 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Adrian Bunk writes: > include/linux/linkage.h in kernel 2.6 includes #define's for __ALIGN and > __ALIGN_STR. In include/asm-i386/linkage.h, their values are changed > #ifdef CONFIG_X86_ALIGNMENT_16. > > It isn't obvious what exacly CONFIG_X86_ALIGNMENT_16 is for (I've heard > more than one opinion), and since the __ALIGN_STR usage in > drivers/pnp/pnpbios/bioscalls.c is the only non-m68k usage of one of > these two #define's I wonder whether you might be able to enlighten me > what CONFIG_X86_ALIGNMENT_16 exactly is for? It's for aligning function entries to a 16 byte boundary instead of only 4 bytes, used together with -malign-functions. See also the ENTRY macro. Note that the default value of __ALIGN is actually useless for anything but x86 and x86-64. Andreas. -- Andreas Schwab, SuSE Labs, schwab@suse.de SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5 "And now for something completely different."