From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Greear Subject: Re: pktgen and spin_lock_bh in xmit path Date: Tue, 20 Oct 2009 16:17:16 -0700 Message-ID: <4ADE44FC.4030406@candelatech.com> References: <4ADD309B.1040505@candelatech.com> <4ADD32FA.6030409@gmail.com> <4ADD41F5.5080707@candelatech.com> <4ADDF560.1020509@candelatech.com> <4ADDF6E5.4070509@gmail.com> <4ADDF948.1050208@candelatech.com> <4ADE0306.6060101@gmail.com> <4ADE0770.8060708@gmail.com> <4ADE2735.9000807@candelatech.com> <4ADE2A24.6080300@gmail.com> <4ADE2C00.8030900@candelatech.com> <4ADE3253.10302@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: NetDev , robert@herjulf.net, "David S. Miller" To: Eric Dumazet Return-path: Received: from mail.candelatech.com ([208.74.158.172]:55611 "EHLO ns3.lanforge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752732AbZJTXRR (ORCPT ); Tue, 20 Oct 2009 19:17:17 -0400 In-Reply-To: <4ADE3253.10302@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: On 10/20/2009 02:57 PM, Eric Dumazet wrote: > Ben Greear a =E9crit : >> That's definitely a nasty little issue. Using skb_set_queue_mapping >> in pktgen makes it run for me, but may just be getting lucky with th= e >> mac-vlan interfaces which will do the dev_queue_xmit (but, I don't s= o much >> care exactly what queue is used as long as things don't crash and th= e >> link doesn't reset). >> >> Don't worry about a quick patch on my account. I seem to have it wo= rking >> to at least some degree (no funny crashes, no link watchdog timeouts= ). >> > > Could you try following patch ? > > This makes queue_mapping invariant if set in range [0 ... real_num_tx= _queues-1] Yes, that runs w/out causing link resets and without crashes (just test= ed it for a few minutes). Interestingly, the pkts sent by pktgen on the mac-vlans end up in tx-queues that match processor ID, even though I'm on .31 where mac-vla= ns have only one tx-queue and pktgen is setting the queue to 0 in the skb (per your previous patch). Must be something somewhere doing the mapping of processor ids to txqs. I'll try to figure this out this evening or tomorrow. Thanks, Ben --=20 Ben Greear Candela Technologies Inc http://www.candelatech.com