Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964782AbWJRGFI (ORCPT ); Wed, 18 Oct 2006 02:05:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964781AbWJRGFH (ORCPT ); Wed, 18 Oct 2006 02:05:07 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:49096 "EHLO ZenIV.linux.org.uk") by vger.kernel.org with ESMTP id S964777AbWJRGFE (ORCPT ); Wed, 18 Oct 2006 02:05:04 -0400 Date: Wed, 18 Oct 2006 07:05:00 +0100 From: Al Viro To: Dave Jones , Linus Torvalds , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org Subject: Re: [RFC] typechecking for get_unaligned/put_unaligned Message-ID: <20061018060500.GI29920@ftp.linux.org.uk> References: <20061017005025.GF29920@ftp.linux.org.uk> <20061017043726.GG29920@ftp.linux.org.uk> <20061018054242.GA21266@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20061018054242.GA21266@redhat.com> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2319 Lines: 49 On Wed, Oct 18, 2006 at 01:42:42AM -0400, Dave Jones wrote: > On Tue, Oct 17, 2006 at 05:37:26AM +0100, Al Viro wrote: > > > There are several #includes with very high impact; the worst happens > > to be module.h -> sched.h > > I gave up fighting to get that fixed a year and a half ago.. > http://lkml.org/lkml/2005/1/26/11 > > rediffing trees with lots of include file juggling gets boring real fast. I don't see a lot of files touched by that one... arch/i386/kernel/alternative.c | 1 + arch/i386/kernel/cpu/mcheck/therm_throt.c | 1 + drivers/base/cpu.c | 1 + drivers/hwmon/abituguru.c | 1 + drivers/leds/ledtrig-ide-disk.c | 1 + drivers/leds/ledtrig-timer.c | 1 + drivers/scsi/scsi_transport_sas.c | 1 + drivers/w1/slaves/w1_therm.c | 1 + include/asm-x86_64/elf.h | 1 - include/linux/acct.h | 1 + include/linux/module.h | 3 ++- include/linux/phy.h | 2 ++ include/scsi/libiscsi.h | 2 ++ kernel/latency.c | 1 + kernel/module.c | 2 +- is hardly a lot. That's the point, actually - apparently we have several high-impact includes that are easy to sever and that are really worth being severed. The part that was not aproiri obvious: * there are clusters of headers around certain dependency counts. * such clusters tend to have leaders - header that pulls the rest and even though other headers are apparently independently included, all such includes end up being hidden by includes of the leader. * gaps between the clusters are pretty large. * dependency graph *on* *clusters* is worth being studied; includes of cluster leader from cluster around slightly smaller dependency count are prime targets for severing. That is the new part here. Not just "dependency graph is a mess and ought to be cleaned up" - _that_ is neither new nor particulary useful... - 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/