From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754956AbXLaPTo (ORCPT ); Mon, 31 Dec 2007 10:19:44 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752144AbXLaPTd (ORCPT ); Mon, 31 Dec 2007 10:19:33 -0500 Received: from moutng.kundenserver.de ([212.227.126.174]:63650 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751004AbXLaPTb (ORCPT ); Mon, 31 Dec 2007 10:19:31 -0500 Date: Mon, 31 Dec 2007 16:19:23 +0100 (CET) From: Bodo Eggert <7eggert@gmx.de> To: Adrian Bunk cc: Bodo Eggert <7eggert@gmx.de>, Jan Engelhardt , devzero@web.de, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [PATCH] Force UNIX domain sockets to be built in In-Reply-To: <20071231144255.GB13803@does.not.exist> Message-ID: References: <20071231122419.GA13803@does.not.exist> <20071231144255.GB13803@does.not.exist> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=us-ascii X-be10.7eggert.dyndns.org-MailScanner-Information: See www.mailscanner.info for information X-be10.7eggert.dyndns.org-MailScanner: Found to be clean X-be10.7eggert.dyndns.org-MailScanner-From: 7eggert@gmx.de X-Provags-ID: V01U2FsdGVkX1/paKzwWkHLalVnxXpLh3kxYx4e4O+YJAzf+fP GUis2Pcx3PEIpWpAM7WSSqtPwFQz7sVUtKUtSxpN/d4ulHRKkt 4r33DN2lvs498azsnHqMg== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 31 Dec 2007, Adrian Bunk wrote: > On Mon, Dec 31, 2007 at 02:26:42PM +0100, Bodo Eggert wrote: > > On Mon, 31 Dec 2007, Adrian Bunk wrote: > > > On Mon, Dec 31, 2007 at 01:09:43PM +0100, Bodo Eggert wrote: > > > > As suggested by Adrian Bunk, UNIX domain sockets should always be built in > > > > on normal systems. This is especially true since udev needs these sockets > > > > and fails to run if UNIX=m. > > > > > > > > Signed-Off-By: Bodo Eggert <7eggert@gmx.de> > > > > > > > > --- > > > > Last minute change: I decided against making it a bool because embedded > > > > folks might depend on a small kernel image. Edited in the patch below. > > > >... > > > > > > Is this just a purely theoretical thought or is this a reasonable use > > > case people actually use in practice? > > > > For now, it's a theoretical thought, but having an embedded device, I can > > see the reason for $EVERYTHING=m there. > > The only advantage I see is that the kernel image you have to flash > can be made smaller - with the disadvantage that the running kernel > is bigger by more than 10%. > > If you don't believe me, try it yourself: > Build all drivers statically into your kernel, and then compare the > vmlinux sizes with CONFIG_MODULES=n and CONFIG_MODULES=y. If you'd aim for a small kernel image, you would build anything as a module that is not requred for booting. > > > After all, changing it to a bool will allow us to make the kernel image > > > for nearly everyone smaller by a few hundred bytes... > > > > I can't see why optionally building it as a module would force us to make > > the kernel bigger. It may be a little more ugly to support =m, but thats it, > > isn't it? > > On architectures like x86 where __exit code is freed at runtime > af_unix_exit() makes your kernel image (but not the running kernel) > bigger. > > With CONFIG_MODULES=y the 13 EXPORT_SYMBOL's that only exist for the > theoretical possibility of CONIG_UNIX=m waste a few hundred bytes > of memory. #define m='m' #if CONIG_UNIX=='m' #define EXPORT_SYMBOL_AF_UNIX EXPORT_SYMBOL #else #define EXPORT_SYMBOL_AF_UNIX() #endif #undef m You could also use "#if defined(C_U) && (C_U == m)". -- Funny quotes: 36. You never really learn to swear until you learn to drive.