From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Fastabend Subject: Re: [RFC PATCH v1 1/2] net: implement mechanism for HW based QOS Date: Thu, 18 Nov 2010 09:31:09 -0800 Message-ID: <4CE562DD.8060904@intel.com> References: <20101117051544.19800.97654.stgit@jf-dev1-dcblab> <20101117091828.GA14773@canuck.infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit To: netdev@vger.kernel.org, nhorman@tuxdriver.com, davem@davemloft.net Return-path: Received: from mga01.intel.com ([192.55.52.88]:2873 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755489Ab0KRRbL (ORCPT ); Thu, 18 Nov 2010 12:31:11 -0500 In-Reply-To: <20101117091828.GA14773@canuck.infradead.org> Sender: netdev-owner@vger.kernel.org List-ID: On 11/17/2010 1:18 AM, Thomas Graf wrote: > On Tue, Nov 16, 2010 at 09:15:45PM -0800, John Fastabend wrote: >> This patch provides a mechanism for lower layer devices to >> steer traffic using skb->priority to tx queues. This allows >> for hardware based QOS schemes to use the default qdisc without >> incurring the penalties related to global state and the qdisc >> lock. While reliably receiving skbs on the correct tx ring >> to avoid head of line blocking resulting from shuffling in >> the LLD. Finally, all the goodness from txq caching and xps/rps >> can still be leveraged. > > Nice. > >> If this approach seems reasonable I'll go ahead and finish >> this up. The priority to tc mapping should probably be exposed >> to userspace either through sysfs or rtnetlink. Any thoughts? > > Please use netlink for this and add a new IFLA_ attribute. I > suggest you put nested attributes into it so you can extend it > later on and/or obsolete attributes: > > [IFLA_TC] = { > [IFLA_TC_MAX_TCS] > [IFLA_TC_NUM_TCS] > [IFLA_TC_TXQCOUNT] > [IFLA_TC_TXQOFFSET] > [IFLA_TC_MAP] > } > > Or whatever is reasonable to export to userspace. Sounds good. I'll do this and post an update. Thanks, John.