From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] bond_alb: don't disable softirq under bond_alb_xmit Date: Sat, 07 Jan 2012 10:14:50 -0800 (PST) Message-ID: <20120107.101450.2214394343146869929.davem@davemloft.net> References: <1325881423-19309-1-git-send-email-maxim.uvarov@oracle.com> <7449.1325885605@death> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: maxim.uvarov@oracle.com, netdev@vger.kernel.org, andy@greyhouse.net, amwang@redhat.com To: fubar@us.ibm.com Return-path: Received: from shards.monkeyblade.net ([198.137.202.13]:49881 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752497Ab2AGSPH (ORCPT ); Sat, 7 Jan 2012 13:15:07 -0500 In-Reply-To: <7449.1325885605@death> Sender: netdev-owner@vger.kernel.org List-ID: From: Jay Vosburgh Date: Fri, 06 Jan 2012 13:33:25 -0800 > Maxim Uvarov wrote: > >>No need to lock soft irqs under bond_alb_xmit() >>which already has softirq disabled. > > In commit: > > commit 6603a6f25e4bca922a7dfbf0bf03072d98850176 > Author: Jay Vosburgh > Date: Wed Oct 17 17:37:50 2007 -0700 > > bonding: Convert more locks to _bh, acquire rtnl, for new locking > > Convert more lock acquisitions to _bh flavor to avoid deadlock > with workqueue activity and add acquisition of RTNL in appropriate places. > Affects ALB mode, as well as core bonding functions and sysfs. > > Signed-off-by: Andy Gospodarek > Signed-off-by: Jay Vosburgh > Signed-off-by: Jeff Garzik > > the _lock_tx_hashtbl was upgraded from regular to _bh to prevent > deadlocks. I don't recall right offhand what deadlock this prevented, > but are we sure there are no possible issues with converting this lock > back to a non-_bh acquisition? Maxim's patch is not changing the BH'ness of the list. He's just avoiding a BH disable which is unnecessary because BH is already disabled in the effected code path(s).