Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754818AbZAISFy (ORCPT ); Fri, 9 Jan 2009 13:05:54 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752183AbZAISFm (ORCPT ); Fri, 9 Jan 2009 13:05:42 -0500 Received: from one.firstfloor.org ([213.235.205.2]:52172 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752053AbZAISFl (ORCPT ); Fri, 9 Jan 2009 13:05:41 -0500 Date: Fri, 9 Jan 2009 19:19:52 +0100 From: Andi Kleen To: Linus Torvalds Cc: Matthew Wilcox , Andi Kleen , Dirk Hohndel , "H. Peter Anvin" , Ingo Molnar , jim owens , Chris Mason , Peter Zijlstra , Steven Rostedt , paulmck@linux.vnet.ibm.com, Gregory Haskins , Andrew Morton , Linux Kernel Mailing List , linux-fsdevel , linux-btrfs , Thomas Gleixner , Nick Piggin , Peter Morreale , Sven Dietrich , jh@suse.cz, richard.guenther@gmail.com Subject: Re: [patch] measurements, numbers about CONFIG_OPTIMIZE_INLINING=y impact Message-ID: <20090109181952.GI26290@one.firstfloor.org> References: <20090109130057.GA31845@elte.hu> <49675920.4050205@hp.com> <20090109153508.GA4671@elte.hu> <49677CB1.3030701@zytor.com> <20090109084620.3c711aad@infradead.org> <20090109172011.GD26290@one.firstfloor.org> <20090109172801.GC6936@parisc-linux.org> <20090109174719.GG26290@one.firstfloor.org> <20090109173914.GD6936@parisc-linux.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 954 Lines: 24 > So we do have special issues. And exactly _because_ we have special issues > we should also expect that some compiler defaults simply won't ever really > be appropriate for us. I agree that the kernel needs quite different inlining heuristics than let's say a template heavy C++ program. I guess that is also where our trouble comes from -- gcc is more tuned for the later. Perhaps because the C++ programmers are better at working with the gcc developers? But it's also not inconceivable that gcc adds a -fkernel-inlining or similar that changes the parameters if we ask nicely. I suppose actually such a parameter would be useful for far more programs than the kernel. -Andi -- ak@linux.intel.com -- 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/