From patchwork Mon Feb 8 20:28:35 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Pitre X-Patchwork-Id: 61443 Delivered-To: patch@linaro.org Received: by 10.112.43.199 with SMTP id y7csp1659748lbl; Mon, 8 Feb 2016 12:44:39 -0800 (PST) X-Received: by 10.98.42.10 with SMTP id q10mr45134080pfq.73.1454964278896; Mon, 08 Feb 2016 12:44:38 -0800 (PST) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id rf10si19878760pab.213.2016.02.08.12.44.38; Mon, 08 Feb 2016 12:44:38 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932364AbcBHUo1 (ORCPT + 30 others); Mon, 8 Feb 2016 15:44:27 -0500 Received: from relais.videotron.ca ([24.201.245.36]:26778 "EHLO relais.videotron.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755888AbcBHUno (ORCPT ); Mon, 8 Feb 2016 15:43:44 -0500 Content-transfer-encoding: 7BIT Received: from yoda.home ([96.23.157.65]) by VL-VM-MR006.ip.videotron.ca (Oracle Communications Messaging Exchange Server 7u4-22.01 64bit (built Apr 21 2011)) with ESMTP id <0O2800F9PWVR0R30@VL-VM-MR006.ip.videotron.ca>; Mon, 08 Feb 2016 15:28:40 -0500 (EST) Received: from xanadu.home (xanadu.home [192.168.2.2]) by yoda.home (Postfix) with ESMTP id 0DC0D2DA053E; Mon, 08 Feb 2016 15:28:40 -0500 (EST) From: Nicolas Pitre To: Michal Marek , linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Al Viro , Rusty Russell Subject: [PATCH 6/6] kconfig option for TRIM_UNUSED_EXPSYMS Date: Mon, 08 Feb 2016 15:28:35 -0500 Message-id: <1454963315-20468-7-git-send-email-nicolas.pitre@linaro.org> X-Mailer: git-send-email 2.5.0 In-reply-to: <1454963315-20468-1-git-send-email-nicolas.pitre@linaro.org> References: <1454963315-20468-1-git-send-email-nicolas.pitre@linaro.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The config option to enable it all. Signed-off-by: Nicolas Pitre --- init/Kconfig | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) -- 2.5.0 diff --git a/init/Kconfig b/init/Kconfig index 22320804fb..893c4979a9 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1990,6 +1990,22 @@ config MODULE_COMPRESS_XZ endchoice +config TRIM_UNUSED_EXPSYMS + bool "Trim unused exported symbols" + depends on MODULES && !UNUSED_SYMBOLS + help + The kernel and some modules make many symbols available for + other modules to use via EXPORT_SYMBOL() and variants. Depending + on the set of modules being selected in your kernel configuration, + many of those exported symbols might never be used. + + This option allows for unused exported symbols to be dropped from + the build. In turn, this provides the compiler more opportunities + (especially when using LTO) for optimizing the code and reducing + binary size. This might have some security advantages as well. + + If unsure say N. + endif # MODULES config MODULES_TREE_LOOKUP