Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758501AbZDWUws (ORCPT ); Thu, 23 Apr 2009 16:52:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755509AbZDWUwj (ORCPT ); Thu, 23 Apr 2009 16:52:39 -0400 Received: from BISCAYNE-ONE-STATION.MIT.EDU ([18.7.7.80]:37924 "EHLO biscayne-one-station.mit.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755473AbZDWUwi (ORCPT ); Thu, 23 Apr 2009 16:52:38 -0400 Date: Thu, 23 Apr 2009 16:48:52 -0400 (EDT) From: Tim Abbott To: Linus Torvalds cc: Linux kernel mailing list , Anders Kaseorg , Waseem Daher , Denys Vlasenko , Rusty Russell , Andi Kleen , "H. Peter Anvin" , Stephen Rothwell , Jeff Arnold , Andrew Morton , Jon Masters , Masami Hiramatsu , "Theodore Ts'o" , Nikanth Karthikesan , Arjan van de Ven , Paul Mundt , =?ISO-8859-15?Q?Am=E9rico_Wang?= Subject: [PATCH v3 0/3] Add support for compiling with -ffunction-sections -fdata-sections In-Reply-To: Message-ID: References: <1238973278-31735-1-git-send-email-tabbott@mit.edu> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Spam-Flag: NO X-Spam-Score: 0.00 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1567 Lines: 37 On Mon, 20 Apr 2009, Linus Torvalds wrote: > I'd be ok with merging it, but I haven't really gotten a strong feeling > that anybody is going to enable it or use it. Linus, Would you be willing to merge the first 3 patches in this patch series at this point? I'm resending these patches to resolve some conflicts that was recently introduced. To summarize the discussion, there are three uses for this code that have significant interest. One is decreasing the kernel size. Denys Vlasenko has numbers that using the linker's --gc-sections option (for which these patches are a prerequisite) saves 10% of the kernel size when CONFIG_MODULES=n, and 1% when CONFIG_MODULES=y. Paul Mundt thinks many embedded users would use this if it were available. A related use is cleaning up a lot of ifdefs that exist only to decrease the kernel size. Several developers commented favorably on the direction of using section garbage collection for dead code removal. Finally, Ksplice depends on the option added by this patch series. The first 3 patches in this patch series fix problems associated with using -ffunction-sections. As there are some architectures currently using -ffunction-sections, these should ideally be merged now, especially the first patch which involves scattered changes. -Tim Abbott -- 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/