From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5BC1CC43381 for ; Thu, 7 Mar 2019 16:00:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2B49320652 for ; Thu, 7 Mar 2019 16:00:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726618AbfCGQAl (ORCPT ); Thu, 7 Mar 2019 11:00:41 -0500 Received: from mout.kundenserver.de ([212.227.126.187]:35995 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726159AbfCGQAk (ORCPT ); Thu, 7 Mar 2019 11:00:40 -0500 Received: from wuerfel.lan ([109.192.41.194]) by mrelayeu.kundenserver.de (mreue012 [212.227.15.129]) with ESMTPA (Nemesis) id 1MfL5v-1gZlkv3lSl-00gs6s; Thu, 07 Mar 2019 17:00:26 +0100 From: Arnd Bergmann To: "David S. Miller" Cc: Arnd Bergmann , Florian Fainelli , Jakub Kicinski , Jiri Pirko , Wenwen Wang , Michal Kubecek , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] [v2] ethtool: reduce stack usage with clang Date: Thu, 7 Mar 2019 16:58:35 +0100 Message-Id: <20190307160017.3120362-1-arnd@arndb.de> X-Mailer: git-send-email 2.20.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Provags-ID: V03:K1:T2IDOyorbgsgPpj+Bqgq7HPPcnC7R+qzlnvnoj1X7TcTxjdySDI zUZqAMZ2WK3VCIVGfBHlgrFIEUlgcDCSazoE08hDgh6ahBC6cP8CCFRId4uFTDA0yyz5GVV fhjgtjkGgIz0T2t1cUSq9vZQVBM3jQD7T7FRyvoHOeglKsVoGWI2uLgWrmtK4k4hzJLCynU 7O6UE/gzzy14hkOMjclzw== X-UI-Out-Filterresults: notjunk:1;V03:K0:M8mJxqWzkoo=:dx+1+v6weoaqHui1MVb2w9 XKlalBcOz+yGzVOqhaVoAr8gvjnwDPXzMMWpkPsP4rsckKA1q+tBqBZilIBWISce754bCwx0P fTL9Qqj2ODSlLE1kyXJdFSzgLJCwsXLU99QwJAh5OL7eeP4HnVzY3Jzj55xtZYkXuXkikcn3j g2N/XMp9vaIllMmzHZD3i+SXkMCXOw4gnWsB6qyHOQhbA/IUjlaHgexPo8TDnlevYhdU44WFO E2EcBXwlPaheZ+C89iXmwkdMgS0Wz1nzSdzpH1H9bsnh578wFkhvoTSSwidj8y5qbjdIxyGsL qhvRTx+KRNyhC1WFbArMmbL0MkQWRFwLtn4GGc0e159wKxBp7ef/iGUpu5tufI2Kkm11Z5R7s JTUIdGm6S9Su8nYJQ+pRacQ3okDSU+qdUyU3XFYmoutl87tchUpIvTVrM5bEglnhnkbpSuYKr sadmFUq+6KZB1SmYRZD1PfFYTjhxIsZ6fDPY53lev4AUrHkd77CW4Y5cpTCzZXgbZ6Gjt38YL HVis3cZUOl6yPZuAVkr6esdi5n9GHzrScHzOxBmIamMltA0d7TKDYkr5y0/wOpb4u1YlHHL04 Dlm5vepNoZfCCwofvpOU5M2QvAwIi0KKSpWw2xD0WpEpBj2gBQlDnomIKykA2Lf51tZoGhClJ H9yl/35o6EsWcFQf2IYgDZBmyeF2PurPiSsth3+UD5M7L/Q/Nr7/tYAoMpocH8dWX1SVVZuVp P5LljWTwfEnRDprZv9eeMIMl6d8JRJLk4/4F9A== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org clang inlines the dev_ethtool() more aggressively than gcc does, leading to a larger amount of used stack space: net/core/ethtool.c:2536:24: error: stack frame size of 1216 bytes in function 'dev_ethtool' [-Werror,-Wframe-larger-than=] Marking the sub-functions that require the most stack space as noinline_for_stack gives us reasonable behavior on all compilers. Signed-off-by: Arnd Bergmann --- v2: don't annotate dev_ethtool itself, as pointed out by Michal Kubecek --- net/core/ethtool.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/net/core/ethtool.c b/net/core/ethtool.c index d4918ffddda8..b1eb32419732 100644 --- a/net/core/ethtool.c +++ b/net/core/ethtool.c @@ -2319,9 +2319,10 @@ static int ethtool_set_tunable(struct net_device *dev, void __user *useraddr) return ret; } -static int ethtool_get_per_queue_coalesce(struct net_device *dev, - void __user *useraddr, - struct ethtool_per_queue_op *per_queue_opt) +static noinline_for_stack int +ethtool_get_per_queue_coalesce(struct net_device *dev, + void __user *useraddr, + struct ethtool_per_queue_op *per_queue_opt) { u32 bit; int ret; @@ -2349,9 +2350,10 @@ static int ethtool_get_per_queue_coalesce(struct net_device *dev, return 0; } -static int ethtool_set_per_queue_coalesce(struct net_device *dev, - void __user *useraddr, - struct ethtool_per_queue_op *per_queue_opt) +static noinline_for_stack int +ethtool_set_per_queue_coalesce(struct net_device *dev, + void __user *useraddr, + struct ethtool_per_queue_op *per_queue_opt) { u32 bit; int i, ret = 0; @@ -2405,7 +2407,7 @@ static int ethtool_set_per_queue_coalesce(struct net_device *dev, return ret; } -static int ethtool_set_per_queue(struct net_device *dev, +static int noinline_for_stack ethtool_set_per_queue(struct net_device *dev, void __user *useraddr, u32 sub_cmd) { struct ethtool_per_queue_op per_queue_opt; -- 2.20.0