From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752058AbdEJEvo (ORCPT ); Wed, 10 May 2017 00:51:44 -0400 Received: from mail.kmu-office.ch ([178.209.48.109]:34549 "EHLO mail.kmu-office.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751720AbdEJEvn (ORCPT ); Wed, 10 May 2017 00:51:43 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Date: Tue, 09 May 2017 21:51:09 -0700 From: Stefan Agner To: David Miller Cc: fugang.duan@nxp.com, andrew@lunn.ch, festevam@gmail.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] net: fec: select queue depending on VLAN priority In-Reply-To: <20170509.093913.1803457630634565212.davem@davemloft.net> References: <20170509053708.2573-1-stefan@agner.ch> <20170509.093913.1803457630634565212.davem@davemloft.net> Message-ID: <6965c0828bb5294faa471af10865a388@agner.ch> User-Agent: Roundcube Webmail/1.2.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2017-05-09 06:39, David Miller wrote: > From: Stefan Agner > Date: Mon, 8 May 2017 22:37:08 -0700 > >> Since the addition of the multi queue code with commit 59d0f7465644 >> ("net: fec: init multi queue date structure") the queue selection >> has been handelt by the default transmit queue selection >> implementation which tries to evenly distribute the traffic across >> all available queues. This selection presumes that the queues are >> using an equal priority, however, the queues 1 and 2 are actually >> of higher priority (the classification of the queues is enabled in >> fec_enet_enable_ring). >> >> This can lead to net scheduler warnings and continuous TX ring >> dumps when exercising the system with iperf. >> >> Use only queue 0 for all common traffic (no VLAN and P802.1p >> priority 0 and 1) and route level 2-7 through queue 1 and 2. >> >> Signed-off-by: Fugang Duan >> Fixes: 59d0f7465644 ("net: fec: init multi queue date structure") > > If the queues are used for prioritization, and it does not have > multiple normal priority level queues, multiqueue is not what the > driver should have implemented. As Andy mentioned, there is also a round-robin mode. I'll try that. What would be the proper way to use the prioritized queues? -- Stefan