Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161124AbWJRPEi (ORCPT ); Wed, 18 Oct 2006 11:04:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1161122AbWJRPEi (ORCPT ); Wed, 18 Oct 2006 11:04:38 -0400 Received: from smtp.osdl.org ([65.172.181.4]:41370 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1161121AbWJRPEg (ORCPT ); Wed, 18 Oct 2006 11:04:36 -0400 Date: Wed, 18 Oct 2006 08:04:24 -0700 (PDT) From: Linus Torvalds To: Al Viro cc: Alexey Dobriyan , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org Subject: Re: dealing with excessive includes In-Reply-To: <20061018093126.GM29920@ftp.linux.org.uk> Message-ID: References: <20061017005025.GF29920@ftp.linux.org.uk> <20061017043726.GG29920@ftp.linux.org.uk> <20061018044054.GH29920@ftp.linux.org.uk> <20061018091944.GA5343@martell.zuzino.mipt.ru> <20061018093126.GM29920@ftp.linux.org.uk> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1028 Lines: 29 On Wed, 18 Oct 2006, Al Viro wrote: > > +#define lock_super(x) do { \ > + struct super_block *sb = x; \ > + get_fs_excl(); \ > + mutex_lock(&sb->s_lock); \ > +} while(0) Don't do this. The "x" passed in may be "sb", and then you end up with bogus code. I think the solution to these kinds of things is either - just bite the bullet, and make it out-of-line. A function call isn't that expensive, and is sometimes actually cheaper due to I$ issues. - have a separate trivial header file, and only include it for people who actually need these things (very few files, actually - it's usually just one file per filesystem) In this case, since it's _so_ simple, and since it's _so_ specialized, I think #2 is the right one. Normally, uninlining would be. Linus - 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/