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=-8.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 3D1BBC04E30 for ; Mon, 9 Dec 2019 14:14:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 115BC207FD for ; Mon, 9 Dec 2019 14:14:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=bfs.de header.i=@bfs.de header.b="tpgCOf8Y" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727877AbfLIOOe (ORCPT ); Mon, 9 Dec 2019 09:14:34 -0500 Received: from mx01-fr.bfs.de ([193.174.231.67]:35326 "EHLO mx01-fr.bfs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726687AbfLIOOd (ORCPT ); Mon, 9 Dec 2019 09:14:33 -0500 Received: from mail-fr.bfs.de (mail-fr.bfs.de [10.177.18.200]) by mx01-fr.bfs.de (Postfix) with ESMTPS id AA9D5201F4; Mon, 9 Dec 2019 15:14:26 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bfs.de; s=dkim201901; t=1575900866; h=from:from:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=VV/fphlTsj7XOOXxkDOSVDjI40GPzBonnX8fbQjETRM=; b=tpgCOf8YgWJE3uVLYXbARPc0s/DmmpdpdIAU0uvDC878YwwYn3J2FT/R+fnrwwblqMFGoN ZCoDnLmZzkG8u96tnhI5NuNOX7sV6V/FJ7lkDi7svSaS5kMMatyJXAVpMT2OZBSuSZaaRS MjZbPLQob5d0TwYzdHmH0apJt4wfRDSHF+h9QEs7n8+FtTjSPEHH0M+5SaQ5dPe6SpjVWr UHF+6liYzaFxVOMGSFMc7yYVVgL+jM1gKLDiSks0BLdT16DRoKQcELUBUF0Ln42brVRwBK Mec3wW97M/79PKtt9nfGlV82oQ8kujT3EQCDZ00fRBukaNn9B/k+Hsr2Va+INw== Received: from [134.92.181.33] (unknown [134.92.181.33]) by mail-fr.bfs.de (Postfix) with ESMTPS id 37CC4BEEBD; Mon, 9 Dec 2019 15:14:24 +0100 (CET) Message-ID: <5DEE56BF.5000102@bfs.de> Date: Mon, 09 Dec 2019 15:14:23 +0100 From: walter harms Reply-To: wharms@bfs.de User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; de; rv:1.9.1.16) Gecko/20101125 SUSE/3.0.11 Thunderbird/3.0.11 MIME-Version: 1.0 To: Mao Wenan CC: davem@davemloft.net, loke.chetan@gmail.com, willemb@google.com, edumazet@google.com, maximmi@mellanox.com, nhorman@tuxdriver.com, pabeni@redhat.com, yuehaibing@huawei.com, tglx@linutronix.de, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org, Xiao Jiangfeng Subject: Re: [PATCH net] af_packet: set defaule value for tmo References: <20191209133125.59093-1-maowenan@huawei.com> In-Reply-To: <20191209133125.59093-1-maowenan@huawei.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Authentication-Results: mx01-fr.bfs.de X-Spamd-Result: default: False [-3.10 / 7.00]; ARC_NA(0.00)[]; HAS_REPLYTO(0.00)[wharms@bfs.de]; BAYES_HAM(-3.00)[100.00%]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; TAGGED_RCPT(0.00)[]; MIME_GOOD(-0.10)[text/plain]; REPLYTO_ADDR_EQ_FROM(0.00)[]; DKIM_SIGNED(0.00)[]; RCPT_COUNT_TWELVE(0.00)[14]; NEURAL_HAM(-0.00)[-0.999,0]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; RCVD_COUNT_TWO(0.00)[2]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_TLS_ALL(0.00)[] Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Am 09.12.2019 14:31, schrieb Mao Wenan: > There is softlockup when using TPACKET_V3: > ... > NMI watchdog: BUG: soft lockup - CPU#2 stuck for 60010ms! > (__irq_svc) from [] (_raw_spin_unlock_irqrestore+0x44/0x54) > (_raw_spin_unlock_irqrestore) from [] (mod_timer+0x210/0x25c) > (mod_timer) from [] > (prb_retire_rx_blk_timer_expired+0x68/0x11c) > (prb_retire_rx_blk_timer_expired) from [] > (call_timer_fn+0x90/0x17c) > (call_timer_fn) from [] (run_timer_softirq+0x2d4/0x2fc) > (run_timer_softirq) from [] (__do_softirq+0x218/0x318) > (__do_softirq) from [] (irq_exit+0x88/0xac) > (irq_exit) from [] (msa_irq_exit+0x11c/0x1d4) > (msa_irq_exit) from [] (handle_IPI+0x650/0x7f4) > (handle_IPI) from [] (gic_handle_irq+0x108/0x118) > (gic_handle_irq) from [] (__irq_usr+0x44/0x5c) > ... > > If __ethtool_get_link_ksettings() is failed in > prb_calc_retire_blk_tmo(), msec and tmo will be zero, so tov_in_jiffies > is zero and the timer expire for retire_blk_timer is turn to > mod_timer(&pkc->retire_blk_timer, jiffies + 0), > which will trigger cpu usage of softirq is 100%. > > Fixes: f6fb8f100b80 ("af-packet: TPACKET_V3 flexible buffer implementation.") > Tested-by: Xiao Jiangfeng > Signed-off-by: Mao Wenan > --- > net/packet/af_packet.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c > index 53c1d41fb1c9..118cd66b7516 100644 > --- a/net/packet/af_packet.c > +++ b/net/packet/af_packet.c > @@ -544,7 +544,8 @@ static int prb_calc_retire_blk_tmo(struct packet_sock *po, > msec = 1; > div = ecmd.base.speed / 1000; > } > - } > + } else > + return DEFAULT_PRB_RETIRE_TOV; > > mbits = (blk_size_in_bytes * 8) / (1024 * 1024); > With some litrle refactoring you can save one indent and make it more readable. err = __ethtool_get_settings(dev, &ecmd); if (err) return DEFAULT_PRB_RETIRE_TOV; speed = ethtool_cmd_speed(&ecmd); if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) return DEFAULT_PRB_RETIRE_TOV; msec = 1; // never changes - needed at all ?? div = speed / 1000; jm2c re, wh