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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 684BCC433EF for ; Tue, 19 Oct 2021 19:15:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4E8BA6137D for ; Tue, 19 Oct 2021 19:15:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232913AbhJSTSD (ORCPT ); Tue, 19 Oct 2021 15:18:03 -0400 Received: from mail.kernel.org ([198.145.29.99]:41090 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230432AbhJSTSC (ORCPT ); Tue, 19 Oct 2021 15:18:02 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 12F156135E; Tue, 19 Oct 2021 19:15:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1634670949; bh=saeUwL+UJoT1ITyT6b5D5yFqwkea6DBOyq/MVsrSG5g=; h=From:To:Cc:Subject:Date:From; b=HZ6qYBbCj1dG16Ui6YZdMQcE7UnEj6Ut6GcJcvx20cwv5ohy/wAEqmBbAirm4R20r SBm0zh2t5mYcTCzuhxtpXgJxsq5SiLHzLvZJpETsRivtQrhUGlMnXtBfstmg7USMpK uFIrOITmwHGMjbBJKy817/JIfuX4cjreHdjmB2xIAgC/G10ihfeRoORDt2TlloxIfb 68dji29NV6UTrh0rlNMrzUC2vW9QnuPygwcizAbgbQKezQocIviQLpLU1z9xbWU92F hu0D1fCXaUH8pz+/7JpEv+lYlp7w51v0k+rn3drmjnS9O9cb4IQbGdx6728XaRlx+d xthVCnYBAllWw== From: Arnd Bergmann To: Jamal Hadi Salim , Cong Wang , Jiri Pirko , "David S. Miller" , Jakub Kicinski , "Ahmed S. Darwish" , Sebastian Andrzej Siewior Cc: Arnd Bergmann , Zheng Yongjun , Eric Dumazet , Randy Dunlap , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] [v2] net: sched: gred: dynamically allocate tc_gred_qopt_offload Date: Tue, 19 Oct 2021 21:15:29 +0200 Message-Id: <20211019191544.3063872-1-arnd@kernel.org> X-Mailer: git-send-email 2.29.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Arnd Bergmann The tc_gred_qopt_offload structure has grown too big to be on the stack for 32-bit architectures after recent changes. net/sched/sch_gred.c:903:13: error: stack frame size (1180) exceeds limit (1024) in 'gred_destroy' [-Werror,-Wframe-larger-than] net/sched/sch_gred.c:310:13: error: stack frame size (1212) exceeds limit (1024) in 'gred_offload' [-Werror,-Wframe-larger-than] Use dynamic allocation per qdisc to avoid this. Fixes: 50dc9a8572aa ("net: sched: Merge Qdisc::bstats and Qdisc::cpu_bstats data types") Fixes: 67c9e6270f30 ("net: sched: Protect Qdisc::bstats with u64_stats") Suggested-by: Jakub Kicinski Signed-off-by: Arnd Bergmann --- Hi Jakub, Not sure if this is what you had in mind, if not it might be easier if you do it yourself. In particular, adding tc_gred_qopt_offload to gred_sched directly rather than as a pointer may be easier here, but that may have other downsides. Changes in v2: - allocate structure at init time rather than inside of gred_offload() --- net/sched/sch_gred.c | 50 ++++++++++++++++++++++++++------------------ 1 file changed, 30 insertions(+), 20 deletions(-) diff --git a/net/sched/sch_gred.c b/net/sched/sch_gred.c index 72de08ef8335..d44958f3411a 100644 --- a/net/sched/sch_gred.c +++ b/net/sched/sch_gred.c @@ -56,6 +56,7 @@ struct gred_sched { u32 DPs; u32 def; struct red_vars wred_set; + struct tc_gred_qopt_offload *opt; }; static inline int gred_wred_mode(struct gred_sched *table) @@ -311,42 +312,45 @@ static void gred_offload(struct Qdisc *sch, enum tc_gred_command command) { struct gred_sched *table = qdisc_priv(sch); struct net_device *dev = qdisc_dev(sch); - struct tc_gred_qopt_offload opt = { - .command = command, - .handle = sch->handle, - .parent = sch->parent, - }; + struct tc_gred_qopt_offload *opt = table->opt; if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc) return; + memset(opt, 0, sizeof(*opt)); + opt->command = command; + opt->handle = sch->handle; + opt->parent = sch->parent; + if (command == TC_GRED_REPLACE) { unsigned int i; - opt.set.grio_on = gred_rio_mode(table); - opt.set.wred_on = gred_wred_mode(table); - opt.set.dp_cnt = table->DPs; - opt.set.dp_def = table->def; + opt->set.grio_on = gred_rio_mode(table); + opt->set.wred_on = gred_wred_mode(table); + opt->set.dp_cnt = table->DPs; + opt->set.dp_def = table->def; for (i = 0; i < table->DPs; i++) { struct gred_sched_data *q = table->tab[i]; if (!q) continue; - opt.set.tab[i].present = true; - opt.set.tab[i].limit = q->limit; - opt.set.tab[i].prio = q->prio; - opt.set.tab[i].min = q->parms.qth_min >> q->parms.Wlog; - opt.set.tab[i].max = q->parms.qth_max >> q->parms.Wlog; - opt.set.tab[i].is_ecn = gred_use_ecn(q); - opt.set.tab[i].is_harddrop = gred_use_harddrop(q); - opt.set.tab[i].probability = q->parms.max_P; - opt.set.tab[i].backlog = &q->backlog; + opt->set.tab[i].present = true; + opt->set.tab[i].limit = q->limit; + opt->set.tab[i].prio = q->prio; + opt->set.tab[i].min = q->parms.qth_min >> q->parms.Wlog; + opt->set.tab[i].max = q->parms.qth_max >> q->parms.Wlog; + opt->set.tab[i].is_ecn = gred_use_ecn(q); + opt->set.tab[i].is_harddrop = gred_use_harddrop(q); + opt->set.tab[i].probability = q->parms.max_P; + opt->set.tab[i].backlog = &q->backlog; } - opt.set.qstats = &sch->qstats; + opt->set.qstats = &sch->qstats; } - dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_GRED, &opt); + dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_GRED, opt); + + return; } static int gred_offload_dump_stats(struct Qdisc *sch) @@ -731,6 +735,7 @@ static int gred_change(struct Qdisc *sch, struct nlattr *opt, static int gred_init(struct Qdisc *sch, struct nlattr *opt, struct netlink_ext_ack *extack) { + struct gred_sched *table = qdisc_priv(sch); struct nlattr *tb[TCA_GRED_MAX + 1]; int err; @@ -754,6 +759,10 @@ static int gred_init(struct Qdisc *sch, struct nlattr *opt, sch->limit = qdisc_dev(sch)->tx_queue_len * psched_mtu(qdisc_dev(sch)); + table->opt = kzalloc(sizeof(table->opt), GFP_KERNEL); + if (!table->opt) + return -ENOMEM; + return gred_change_table_def(sch, tb[TCA_GRED_DPS], extack); } @@ -910,6 +919,7 @@ static void gred_destroy(struct Qdisc *sch) gred_destroy_vq(table->tab[i]); } gred_offload(sch, TC_GRED_DESTROY); + kfree(table->opt); } static struct Qdisc_ops gred_qdisc_ops __read_mostly = { -- 2.29.2