From patchwork Fri Feb 3 08:02:16 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Ian Campbell X-Patchwork-Id: 139311 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 30FCC104792 for ; Fri, 3 Feb 2012 19:02:57 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754675Ab2BCICj (ORCPT ); Fri, 3 Feb 2012 03:02:39 -0500 Received: from smtp.ctxuk.citrix.com ([62.200.22.115]:38461 "EHLO SMTP.EU.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752407Ab2BCICS (ORCPT ); Fri, 3 Feb 2012 03:02:18 -0500 X-IronPort-AV: E=Sophos;i="4.73,351,1325462400"; d="scan'208";a="10458715" Received: from lonpmailmx01.citrite.net ([10.30.203.162]) by LONPIPO01.EU.CITRIX.COM with ESMTP/TLS/RC4-MD5; 03 Feb 2012 08:02:17 +0000 Received: from [127.0.0.1] (10.80.16.67) by smtprelay.citrix.com (10.30.203.162) with Microsoft SMTP Server id 8.3.213.0; Fri, 3 Feb 2012 08:02:17 +0000 Message-ID: <1328256136.13189.34.camel@dagon.hellion.org.uk> Subject: Re: [RFC PATCH V4 02/13] netback: add module unload function. From: Ian Campbell To: Eric Dumazet CC: Paul Gortmaker , "Wei Liu (Intern)" , "netdev@vger.kernel.org" , "xen-devel@lists.xensource.com" , "konrad.wilk@oracle.com" Date: Fri, 3 Feb 2012 08:02:16 +0000 In-Reply-To: <1328253910.2480.41.camel@edumazet-laptop> References: <1328201363-13915-1-git-send-email-wei.liu2@citrix.com> <1328201363-13915-3-git-send-email-wei.liu2@citrix.com> <1328202524.11534.3.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> <1328203710.5553.94.camel@leeds.uk.xensource.com> <1328204936.13262.4.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> <1328212761.28964.77.camel@dagon.hellion.org.uk> <1328214866.2480.18.camel@edumazet-laptop> <1328215821.13189.24.camel@dagon.hellion.org.uk> <1328251092.13189.29.camel@dagon.hellion.org.uk> <1328253910.2480.41.camel@edumazet-laptop> Organization: Citrix Systems, Inc. X-Mailer: Evolution 3.2.2-1 MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Fri, 2012-02-03 at 07:25 +0000, Eric Dumazet wrote: > Le vendredi 03 février 2012 à 06:38 +0000, Ian Campbell a écrit : > > On Thu, 2012-02-02 at 22:52 +0000, Paul Gortmaker wrote: > > > On Thu, Feb 2, 2012 at 3:50 PM, Ian Campbell wrote: > > > > On Thu, 2012-02-02 at 20:34 +0000, Eric Dumazet wrote: > > > > > > [...] > > > > > > > > > > > I don't think it is at all unreasonable to ask for bug fixes but in this > > > > case Wei's series is removing the code in question (which would also > > > > undoubtedly fix the bug). > > > > > > > > As it happens the fix turns out to be simple but if it were complex I > > > > would perhaps have disagreed more strongly about spending effort fixing > > > > code that is removed 2 patches later, although obviously that would have > > > > depended on the specifics of the fix in that case. > > > > > > Lots of people are relying on git bisect. If you introduce build failures > > > or known bugs into any point in history, you take away from the value > > > in git bisect. Sure, it happens by accident, but it shouldn't ever be > > > done knowingly. > > > > Sure. In this case the bug has been there since 2.6.39, it isn't > > introduced by this series. > > > > We are stuck right now with a bug introduced in 2.6.39, (IP redirects), > and because fix was done in 3.1, we are unable to provide a fix fo > stable 3.0 kernel. > > Something that takes 15 minutes to fix now, can take several days of > work later. Sure. Here is the patch. I've compile tested it but not run it yet since I'm supposed to be packing for a trip, I'll be back on Wednesday. It seems straight forward enough though. 8<-------------------------------- From 6f3d3068f6e049c2d810f9fc667d57667bea77dc Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Fri, 3 Feb 2012 07:47:23 +0000 Subject: [PATCH] xen: netback: do not bind netback threads to specific CPUs netback_init does not take proper account of which CPUs is online. However we don't require a thread per CPU, just a pool of worker threads, of which the number of CPUs at start of day is as good a number as any. Therefore do not bind netback threads to particular CPUs. Signed-off-by: Ian Campbell Cc: Eric Dumazet Cc: Wei Lui --- drivers/net/xen-netback/netback.c | 2 -- 1 files changed, 0 insertions(+), 2 deletions(-) diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 59effac..31ad3ee 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -1670,8 +1670,6 @@ static int __init netback_init(void) goto failed_init; } - kthread_bind(netbk->task, group); - INIT_LIST_HEAD(&netbk->net_schedule_list); spin_lock_init(&netbk->net_schedule_list_lock);