From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [RFC net-2.6 PATCH] ixgbe: need to purge skb qdisc lists when changing real_num_tx_queues Date: Mon, 28 Jun 2010 21:19:30 -0700 (PDT) Message-ID: <20100628.211930.102546288.davem@davemloft.net> References: <20100621052520.2417.65984.stgit@jf-dev1-dcblab> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, jeffrey.t.kirsher@intel.com To: john.r.fastabend@intel.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:34965 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750734Ab0F2ETR (ORCPT ); Tue, 29 Jun 2010 00:19:17 -0400 In-Reply-To: <20100621052520.2417.65984.stgit@jf-dev1-dcblab> Sender: netdev-owner@vger.kernel.org List-ID: From: John Fastabend Date: Sun, 20 Jun 2010 22:25:20 -0700 > This patch exports dev_deactivate() symbol. > > The qdisc needs to be purged when real_num_tx_queues is > changed so that skbs do not hit ndo_start_xmit with > queue_mappings corresponding to tx_rings already freed. > > real_num_tx_queues is changed when dynamically enabling or > disabling DCB or FCoE. To purge the qdisc use dev_deactivate(). > > Signed-off-by: John Fastabend Whatever it is that needs to happen when real_num_tx_queues changes outght to be transparent to drivers. Therefore we should hide all of these details behind a well named interface drivers can call when they need to change real_num_tx_queues.