Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757337AbZDXOWT (ORCPT ); Fri, 24 Apr 2009 10:22:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758089AbZDXOWF (ORCPT ); Fri, 24 Apr 2009 10:22:05 -0400 Received: from mx2.redhat.com ([66.187.237.31]:56816 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759497AbZDXOWE (ORCPT ); Fri, 24 Apr 2009 10:22:04 -0400 Message-ID: <49F1CA6E.5080407@redhat.com> Date: Fri, 24 Apr 2009 10:19:26 -0400 From: Masami Hiramatsu User-Agent: Thunderbird 2.0.0.21 (X11/20090320) MIME-Version: 1.0 To: Tim Abbott CC: Linus Torvalds , 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 , "Theodore Ts'o" , Nikanth Karthikesan , Arjan van de Ven , Paul Mundt , =?ISO-8859-1?Q?Am=E9rico_Wang?= Subject: Re: [PATCH v3 0/3] Add support for compiling with -ffunction-sections -fdata-sections References: <1238973278-31735-1-git-send-email-tabbott@mit.edu> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2189 Lines: 61 Tim Abbott wrote: > 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. Hi Tim, What would you think about posting these patches plus -ffunction-sections/ -fdata-sections patch to -mm tree, -tip tree, or -next tree as "playable" Ksplice patchset? If people use it and see it enough stable and useful, those patches will be automatically pulled into linus kernel. > 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. If there are actual problems on those arch, I think you'd better post these patches as bugfixes with bug reports. Thank you, -- Masami Hiramatsu Software Engineer Hitachi Computer Products (America) Inc. Software Solutions Division e-mail: mhiramat@redhat.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/