From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762264Ab3DBThT (ORCPT ); Tue, 2 Apr 2013 15:37:19 -0400 Received: from mga02.intel.com ([134.134.136.20]:17053 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752331Ab3DBThP (ORCPT ); Tue, 2 Apr 2013 15:37:15 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.87,394,1363158000"; d="scan'208";a="311336735" Date: Tue, 2 Apr 2013 12:37:15 -0700 From: Sarah Sharp To: David Howells Cc: Greg Kroah-Hartman , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] xhci: Rename SEGMENT_SIZE and SEGMENT_SHIFT as the former is used in a.out.h Message-ID: <20130402193715.GA3693@xanatos> References: <20130329001048.GK5995@xanatos> <20130328201505.GC5995@xanatos> <20130328184827.29679.62426.stgit@warthog.procyon.org.uk> <20130328184835.29679.62285.stgit@warthog.procyon.org.uk> <32349.1364509973@warthog.procyon.org.uk> <20541.1364926056@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20541.1364926056@warthog.procyon.org.uk> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 02, 2013 at 07:07:36PM +0100, David Howells wrote: > Sarah Sharp wrote: > > > I guess my question is a deeper one: do we need to rename all the xHCI > > macros to have the XHCI_ prefix, in order to avoid future collision? > > For example, one of the macros is MAX_HC_PORTS, which could possibly be > > used by other host drivers in the future. > > Hmmm... > > I suspect the question is whether your symbols are likely to collide with > core symbols rather than symbols of unrelated drivers - after all, you're > unlikely to be #including the headers of those drivers. > > I personally prefer to prefix the names of symbols in drivers with something > consistent for that driver to reduce namespace collisions - but I know not > everyone cares about that. Linux doesn't have much of a policy in this area > though. I also like it because it makes tags easier to use (fewer definitions > of the same symbol). > > Whether you should go back and rename existing xHCI functions, I don't know. > I'd be tempted to leave it for now unless there's some collision. However, > things like MAX_HC_PORTS does seem a little generic. Further #define > collisions go unnoticed under some circumstances. Two obvious cases are (a) > redefinition of a symbol because it happens to be the same value and (b) where > the second one is accidentally suppressed because it is wrapped in a > conditional. Hmm, yeah, I think it doesn't make sense to change all the macros now. If I were starting a new driver, I think I would use a common prefix. I'll add the macro renaming to my todo list and see if I can get some newbie to take it on. 8) > Perhaps we should move to C++ and use namespaces;-) Hah! Sarah Sharp