Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754801AbZAIR7M (ORCPT ); Fri, 9 Jan 2009 12:59:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752925AbZAIR6h (ORCPT ); Fri, 9 Jan 2009 12:58:37 -0500 Received: from smtp1.linux-foundation.org ([140.211.169.13]:42396 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752292AbZAIR6d (ORCPT ); Fri, 9 Jan 2009 12:58:33 -0500 Date: Fri, 9 Jan 2009 09:57:30 -0800 (PST) From: Linus Torvalds X-X-Sender: torvalds@localhost.localdomain To: Andi Kleen cc: Dirk Hohndel , Matthew Wilcox , "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 Subject: Re: [patch] measurements, numbers about CONFIG_OPTIMIZE_INLINING=y impact In-Reply-To: <20090109180213.GH26290@one.firstfloor.org> Message-ID: 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> <20090109094142.367012b6@infradead.org> <20090109180213.GH26290@one.firstfloor.org> User-Agent: Alpine 2.00 (LFD 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1028 Lines: 26 On Fri, 9 Jan 2009, Andi Kleen wrote: > > Universal noinline would also be a bad idea because of its > costs (4.1% text size increase). Perhaps should make it > a CONFIG option for debugging though. That's _totally_ the wrong way. If you can reproduce an issue on your machine, you generally don't care about inline, because you can see the stack, do the whole "gdb vmlinux" thing, and you generally have tools to help you decode things. Including just recompiling the kernel with an added noinline. But _users_ just get their oopses sent automatically. So it's not about "debugging kernels", it's about _normal_ kernels. They are the ones that need to be debuggable, and the ones that care most about things like the symbolic EIP being as helpful as possible. 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/